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Sample records for alteration processes occurred

  1. Volcanic glasses, their origins and alteration processes

    Science.gov (United States)

    Friedman, I.; Long, W.

    1984-01-01

    Natural glass can be formed by volcanic processes, lightning (fulgarites) burning coal, and by meteorite impact. By far the most common process is volcanic - basically the glass is rapidly chilled molten rock. All natural glasses are thermodynamically unstable and tend to alter chemically or to crystallize. The rate of these processes is determined by the chemical composition of the magma. The hot and fluid basaltic melts have a structure that allows for rapid crystal growth, and seldom forms glass selvages greater than a few centimeters thick, even when the melt is rapidly cooled by extrusion in the deep sea. In contrast the cooler and very viscous rhyolitic magmas can yield bodies of glass that are tens of meters thick. These highly polymerized magmas have a high silica content - often 71-77% SiO2. Their high viscosity inhibits diffusive crystal growth. Basalt glass in sea water forms an alteration zone called palagonite whose thickness increases linearly with time. The rate of diffusion of water into rhyolitic glass, which follows the relationship - thickness = k (time) 1 2, has been determined as a function of the glass composition and temperature. Increased SiO2 increases the rate, whereas increased CaO, MgO and H2O decrease the rate. The activation energy of water diffusion varies from about 19 to 22 kcal/mol. for the glasses studied. The diffusion of alkali out of rhyolite glass occurs simultaneously with water diffusion into the glass. The rate of devitrification of rhyolitic glass is a function of the glass viscosity, which in turn is a function of water content and temperature. Although all of the aforementioned processes tend to destroy natural glasses, the slow rates of these processes, particularly for rhyolitic glass, has allowed samples of glass to persist for 60 million years. ?? 1984.

  2. Enhanced Expression of Interferon-γ-Induced Antigen-Processing Machinery Components in a Spontaneously Occurring Cancer

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    Fulvia Cerruti

    2007-11-01

    Full Text Available In human tumors, changes in the surface expression and/or function of major histocompatibility complex (MHC class I antigens are frequently found and may provide malignant cells with a mechanism to escape control of the immune system. This altered human lymphocyte antigen (HLA class I phenotype can be caused by either structural alterations or dysregulation of genes encoding subunits of HLA class I antigens and/or components of the MHC class I antigen-processing machinery (APM. Herein we analyze the expression of several proteins involved in the generation of MHC class I epitopes in feline injection site sarcoma, a spontaneously occurring tumor in cats that is an informative model for the study of tumor biology in other species, including humans. Eighteen surgically removed primary fibrosarcoma lesions were analyzed, and an enhanced expression of two catalytic subunits of immunoproteasomes, PA28 and leucine aminopeptidase, was found in tumors compared to matched normal tissues. As a functional counterpart of these changes in protein levels, proteasomal activities were increased in tissue extracts from fibrosarcomas. Taken together, these results suggest that alterations in the APM system may account for reduced processing of selected tumor antigens and may potentially provide neoplastic fibroblasts with a mechanism for escape from T-cell recognition and destruction.

  3. Frontal cortex gray matter volume alterations in pathological gambling occur independently from substance use disorder.

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    Zois, Evangelos; Kiefer, Falk; Lemenager, Tagrid; Vollstädt-Klein, Sabine; Mann, Karl; Fauth-Bühler, Mira

    2017-05-01

    Neuroimaging in pathological gambling (PG) allows studying brain structure independent of pharmacological/neurotoxic effects occurring in substance addiction. Because of high comorbidity of PG with substance use disorder (SUD), first results on structural deficits in PG are controversial. The current investigation is the first to examine gray matter (GM) volume alterations in PG controlling for the impact of SUD by comparing non-comorbid (PG PURE ) and two comorbid (PG ALCOHOL and PG POLY ) groups. Two hundred and five individuals were included in the analysis: 107 patients diagnosed with PG and 98 healthy controls (HCs). We employed voxel-based morphometry to look for GM volume differences between the groups controlling for age, smoking and depression. GM decreases in the superior medial and orbital frontal cortex occur independently of substance use in PG PURE compared with HCs. The frontal pattern of GM decrease was comparable with PG ALCOHOL group where additionally GM volume was decreased in the anterior cingulate but increased in the amygdala. Moreover, regions in PG ALCOHOL + POLY with reduced GM volume were the medial frontal, anterior cingulate and occipital lobe regions. PG ALCOHOL + POLY not only exhibited structural deficits in comparison with HCs but also relative to PG PURE in the precuneus and post-central gyrus. We demonstrated specific frontal cortex GM deficits in PG without SUD comorbidities. Whereas some target regions reported in earlier studies might result from comorbid substance abuse, there seems to be a core set of frontal alterations associated with addicted gambling behaviour independent of toxic substance effects. © 2016 Society for the Study of Addiction.

  4. Electromagnetic Evidence of Altered Visual Processing in Autism

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    Neumann, Nicola; Dubischar-Krivec, Anna M.; Poustka, Fritz; Birbaumer, Niels; Bolte, Sven; Braun, Christoph

    2011-01-01

    Individuals with autism spectrum disorder (ASD) demonstrate intact or superior local processing of visual-spatial tasks. We investigated the hypothesis that in a disembedding task, autistic individuals exhibit a more local processing style than controls, which is reflected by altered electromagnetic brain activity in response to embedded stimuli…

  5. Naturally Occurring Radioactive Materials (NORM)

    International Nuclear Information System (INIS)

    Gray, P.

    1997-01-01

    This paper discusses the broad problems presented by Naturally Occuring Radioactive Materials (NORM). Technologically Enhanced naturally occuring radioactive material includes any radionuclides whose physical, chemical, radiological properties or radionuclide concentration have been altered from their natural state. With regard to NORM in particular, radioactive contamination is radioactive material in an undesired location. This is a concern in a range of industries: petroleum; uranium mining; phosphorus and phosphates; fertilizers; fossil fuels; forestry products; water treatment; metal mining and processing; geothermal energy. The author discusses in more detail the problem in the petroleum industry, including the isotopes of concern, the hazards they present, the contamination which they cause, ways to dispose of contaminated materials, and regulatory issues. He points out there are three key programs to reduce legal exposure and problems due to these contaminants: waste minimization; NORM assesment (surveys); NORM compliance (training)

  6. Naturally Occurring Radioactive Materials (NORM)

    Energy Technology Data Exchange (ETDEWEB)

    Gray, P. [ed.

    1997-02-01

    This paper discusses the broad problems presented by Naturally Occuring Radioactive Materials (NORM). Technologically Enhanced naturally occuring radioactive material includes any radionuclides whose physical, chemical, radiological properties or radionuclide concentration have been altered from their natural state. With regard to NORM in particular, radioactive contamination is radioactive material in an undesired location. This is a concern in a range of industries: petroleum; uranium mining; phosphorus and phosphates; fertilizers; fossil fuels; forestry products; water treatment; metal mining and processing; geothermal energy. The author discusses in more detail the problem in the petroleum industry, including the isotopes of concern, the hazards they present, the contamination which they cause, ways to dispose of contaminated materials, and regulatory issues. He points out there are three key programs to reduce legal exposure and problems due to these contaminants: waste minimization; NORM assesment (surveys); NORM compliance (training).

  7. Corrected simulations for one-dimensional diffusion processes with naturally occurring boundaries.

    Science.gov (United States)

    Shafiey, Hassan; Gan, Xinjun; Waxman, David

    2017-11-01

    To simulate a diffusion process, a usual approach is to discretize the time in the associated stochastic differential equation. This is the approach used in the Euler method. In the present work we consider a one-dimensional diffusion process where the terms occurring, within the stochastic differential equation, prevent the process entering a region. The outcome is a naturally occurring boundary (which may be absorbing or reflecting). A complication occurs in a simulation of this situation. The term involving a random variable, within the discretized stochastic differential equation, may take a trajectory across the boundary into a "forbidden region." The naive way of dealing with this problem, which we refer to as the "standard" approach, is simply to reset the trajectory to the boundary, based on the argument that crossing the boundary actually signifies achieving the boundary. In this work we show, within the framework of the Euler method, that such resetting introduces a spurious force into the original diffusion process. This force may have a significant influence on trajectories that come close to a boundary. We propose a corrected numerical scheme, for simulating one-dimensional diffusion processes with naturally occurring boundaries. This involves correcting the standard approach, so that an exact property of the diffusion process is precisely respected. As a consequence, the proposed scheme does not introduce a spurious force into the dynamics. We present numerical test cases, based on exactly soluble one-dimensional problems with one or two boundaries, which suggest that, for a given value of the discrete time step, the proposed scheme leads to substantially more accurate results than the standard approach. Alternatively, the standard approach needs considerably more computation time to obtain a comparable level of accuracy to the proposed scheme, because the standard approach requires a significantly smaller time step.

  8. Impacts of an invasive plant are fundamentally altered by a co-occurring forest disturbance.

    Science.gov (United States)

    Sokol, Noah W; Kuebbing, Sara E; Bradford, Mark A

    2017-08-01

    Invasive species frequently co-occur with other disturbances, which can impact the same ecosystem functions as the invader. Yet invasion studies rarely control for the presence of these other disturbances, although their overlapping effects may influence the direction and magnitude of impacts attributed to the invader alone. Here, we ask whether controlling for the presence of a co-occurring disturbance, as well as the time since disturbance, yields different values of an invader's ecosystem effects than when these factors remain unaddressed. We used a chronosequence of six forest stands at a single site: five logged stands that each contained paired invaded-uninvaded plots of the forest understory invasive grass Microstegium vimineum, as well as one unlogged and uninvaded control stand. By controlling for the presence of both logging and invasion, we untangled the effects of each through time. We found that the co-occurring disturbance of logging can dramatically alter the measured effects of M. vimineum by amplifying, dampening, negating, or entirely reversing the direction of the invader's impacts. During its period of peak impact, logging amplified the invader's positive effect on the size of the soil microbial biomass pool by 24%, reduced the invader's positive effect on soil water holding capacity by 5%, negated the invader's positive effect on the particulate organic matter carbon pool (from a 9% increase to no significant effect), and reversed the direction of the invader's impact on net nitrogen mineralization rate from a 51% increase to a 52% decrease. Furthermore, the influence of logging on the invader's impacts was not static, but dynamic through time. The results from our site therefore demonstrate that failure to account for the impacts of a co-occurring disturbance, as well as the time since disturbance, can result in flawed inference about the nature of an invader's effects. Future research should determine how widespread such flawed inference

  9. Prenatal IV Cocaine: Alterations in Auditory Information Processing

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    Charles F. Mactutus

    2011-06-01

    Full Text Available One clue regarding the basis of cocaine-induced deficits in attentional processing is provided by the clinical findings of changes in the infants’ startle response; observations buttressed by neurophysiological evidence of alterations in brainstem transmission time. Using the IV route of administration and doses that mimic the peak arterial levels of cocaine use in humans, the present study examined the effects of prenatal cocaine on auditory information processing via tests of the acoustic startle response (ASR, habituation, and prepulse inhibition (PPI in the offspring. Nulliparous Long-Evans female rats, implanted with an IV access port prior to breeding, were administered saline, 0.5, 1.0, or 3.0 mg/kg/injection of cocaine HCL (COC from gestation day (GD8-20 (1x/day-GD8-14, 2x/day-GD15-20. COC had no significant effects on maternal/litter parameters or growth of the offspring. At 18-20 days of age, one male and one female, randomly selected from each litter displayed an increased ASR (>30% for males at 1.0 mg/kg and >30% for females at 3.0 mg/kg. When reassessed in adulthood (D90-100, a linear dose-response increase was noted on response amplitude. At both test ages, within-session habituation was retarded by prenatal cocaine treatment. Testing the females in diestrus vs. estrus did not alter the results. Prenatal cocaine altered the PPI response function across interstimulus interval (ISI and induced significant sex-dependent changes in response latency. Idazoxan, an alpha2-adrenergic receptor antagonist, significantly enhanced the ASR, but less enhancement was noted with increasing doses of prenatal cocaine. Thus, in utero exposure to cocaine, when delivered via a protocol designed to capture prominent features of recreational usage, causes persistent, if not permanent, alterations in auditory information processing, and suggests dysfunction of the central noradrenergic circuitry modulating, if not mediating, these responses.

  10. Altered central pain processing after pancreatic surgery for chronic pancreatitis

    NARCIS (Netherlands)

    Bouwense, S. A.; Ahmed Ali, U.; ten Broek, R. P.; Issa, Y.; van Eijck, C. H.; Wilder-Smith, O. H.; van Goor, H.

    2013-01-01

    Chronic abdominal pain is common in chronic pancreatitis (CP) and may involve altered central pain processing. This study evaluated the relationship between pain processing and pain outcome after pancreatic duct decompression and/or pancreatic resection in patients with CP. Patients with CP

  11. Music and Alterity Processes

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    Josep Martí

    2014-10-01

    Full Text Available The concept of alterity constitutes an important issue in anthropological research and, therefore, in the study of musical practices, as well. Without it, we could hardly understand other kinds of music situated in different spaces and time from the observer. In order to effectively approach these musical practices, we have to develop strategies to help us reduce as much as possible that which distorts the vision of the other. However, beyond the strictly epistemological and methodological issues, the study of music cannot ignore the ethical question related to the manner in which Western thought has understood and treated the other: through a hierarchical and stereotypical type of thinking based on the condition of otherness. Throughout the article, different alterity procedures are presented and discussed, such as synecdochization, exoticization, undervaluation, overvaluation, misunderstanding and exclusion. Taking these different alterity strategies into account may help us to better understand how the musical other is constructed, used and ultimately instrumentalized.

  12. Food carotenoids: analysis, composition and alterations during storage and processing of foods.

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    Rodriguez-Amaya, Delia B

    2003-01-01

    Substantial progress has been achieved in recent years in refining the analytical methods and evaluating the accuracy of carotenoid data. Although carotenoid analysis is inherently difficult and continues to be error prone, more complete and reliable data are now available. Rather than expressing the analytical results as retinol equivalents, there is a tendency to present the concentrations of individual carotenoids, particularly beta-carotene, beta-cryptoxanthin, alpha-carotene, lycopene, lutein and zeaxanthin, carotenoids found in the human plasma and considered to be important to human health in terms of the provitamin A activity and/or reduction of the risk for developing degenerative diseases. With the considerable effort directed to carotenoid analysis, many food sources have now been analyzed in different countries. The carotenoid composition of foods vary qualitatively and quantitatively. Even in a given food, compositional variability occurs because of factors such as stage of maturity, variety or cultivar, climate or season, part of the plant consumed, production practices, post-harvest handling, processing and storage of food. During processing, isomerization of trans-carotenoids, the usual configuration in nature, to the cis-forms occurs, with consequent alteration of the carotenoids' bioavailability and biological activity. Isomerization is promoted by light, heat and acids. The principal cause of carotenoid loss during processing and storage of food is enzymatic or non-enzymatic oxidation of the highly unsaturated carotenoid molecules. The occurrence and extent of oxidation depends on the presence of oxygen, metals, enzymes, unsaturated lipids, prooxidants, antioxidants; exposure to light; type and physical state of the carotenoids present; severity and duration of processing; packaging material; storage conditions. Thus, retention of carotenoids has been the major concern in the preparation, processing and storage of foods. However, in recent years

  13. Can bread processing conditions alter glycaemic response?

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    Lau, Evelyn; Soong, Yean Yean; Zhou, Weibiao; Henry, Jeyakumar

    2015-04-15

    Bread is a staple food that is traditionally made from wheat flour. This study aimed to compare the starch digestibility of western baked bread and oriental steamed bread. Four types of bread were prepared: western baked bread (WBB) and oriental steamed bread (OSB), modified baked bread (MBB) made with the OSB recipe and WBB processing, and modified steamed bread (MSB) made with the WBB recipe and OSB processing. MBB showed the highest starch digestibility in vitro, followed by WBB, OSB and MSB. A similar trend was observed for glycaemic response in vivo. MBB, WBB, OSB and MSB had a glycaemic index of 75±4, 71±5, 68±5 and 65±4, respectively. Processing differences had a more pronounced effect on starch digestibility in bread, and steamed bread was healthier in terms of glycaemic response. The manipulation of processing conditions could be an innovative route to alter the glycaemic response of carbohydrate-rich foods. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Preferential processing of self-relevant stimuli occurs mainly at the perceptual and conscious stages of information processing.

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    Tacikowski, P; Ehrsson, H H

    2016-04-01

    Self-related stimuli, such as one's own name or face, are processed faster and more accurately than other types of stimuli. However, what remains unknown is at which stage of the information processing hierarchy this preferential processing occurs. Our first aim was to determine whether preferential self-processing involves mainly perceptual stages or also post-perceptual stages. We found that self-related priming was stronger than other-related priming only because of perceptual prime-target congruency. Our second aim was to dissociate the role of conscious and unconscious factors in preferential self-processing. To this end, we compared the "self" and "other" conditions in trials where primes were masked or unmasked. In two separate experiments, we found that self-related priming was stronger than other-related priming but only in the unmasked trials. Together, our results suggest that preferential access to the self-concept occurs mainly at the perceptual and conscious stages of the stimulus processing hierarchy. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  15. Understanding the processes involved in weathering and experimental alteration of glassy materials. The case of some volcanic glasses from eastern Sicily (Italy)

    International Nuclear Information System (INIS)

    Liotta, Angelo

    2014-01-01

    The objective of this thesis is to study the effects of weathering and experimental alteration in order to understand the geochemical processes involved and the variation of mineral phases in altered natural glasses. For the first time, five samples of natural volcanic glasses having different composition were collected in eastern Sicily (Italy) in order to be artificially altered and analyzed. The study of naturally altered samples has allowed to observe the effects of weathering after a period of time corresponding to the age of the sample. Moreover, the use of samples of natural glass of volcanic origin has allowed to obtain some powder or thin plates of fresh silicate glass that have been subjected to artificial alteration in the laboratory, in order to model the geochemical processes that have occurred. Alteration experiments were conducted in pure water at 90 C; samples have been altered from 1 to 1000 days of experiment. The characterization of the samples was obtained by Raman spectroscopy, which showed the effects of the devitrification and the presence of some secondary minerals such as carbonates and anatase on the obsidian thin plates, but also phillipsite and chabazite, two varieties of zeolite usually found in the cavities of oldest basalts. Solid modifications were observed by SEM. The analysis showed the formation of several secondary minerals having a composition compatible with smectites, determined by EDS spectroscopy. All these results allow to test the geochemical modeling in the long term. Further analysis will be needed to reach a full understanding of the weathering of glassy materials. (author)

  16. Sustainability and the anthropogenic alteration of evolutionary processes

    Directory of Open Access Journals (Sweden)

    John Cairns, Jr.

    2004-08-01

    Full Text Available Persuasive evidence indicates that Earth is now experiencing a major biotic crisis. Even if humankind ceases severe stress on natural systems, the crisis will probably disrupt the basic evolutionary processes that characterized the period preceding the agricultural and industrial revolutions.Proliferation of drug and pesticide resistant species and opportunistic species that thrive in human-dominated ecosystems will become increasingly common. The effect on humankind of altering basic evolutionary processes is uncertain because the understanding of these processes is not robust. The probable result will not be an environment as favorable to humans as the one that has existed for most of human history. Humans probably have altered the environment since Homo sapiens first appeared. However, only in the last two centuries has the degree and rate of change reached levels now considered by many people to be ‘normal’, even though the record shows they are not.Greatly improved technology has facilitated increased exploitation of natural resources to unsustainablelevels. This exploitation, in turn, has led to exponential human population growth, which has depleted natural capital (living systems and the services they provide. Economic globalization has ensured that ecosystems far distant from consumers can be and are profitably exploited. Economicgrowth has become a universal mantra that is coupled with a conviction that such growth can continue indefinitely on a finite planet. A major paradigm shift is essential if sustainable use of the planet is to become a reality.

  17. The nature and position of processing determines why forgetting occurs in working memory tasks.

    Science.gov (United States)

    Jarrold, Christopher; Tam, Helen; Baddeley, Alan D; Harvey, Caroline E

    2010-12-01

    The effect of potentially distracting processing within working memory was examined by varying the nature and position of processing across conditions of a Brown-Peterson-like task. Separate groups of participants carried out verbal or visuospatial processing operations on identical stimuli, while retaining lists of to-be-remembered words. The number of words presented either before or after the processing interval was varied systematically. Results showed that although verbal processing was no more demanding than visuospatial processing, it led to greater forgetting. However, forgetting was confined to items presented prior to processing, and the difference in degree of forgetting shown by the two groups was maximal when four items occurred before processing. Temporal isolation effects were more marked in the verbal processing group. These findings indicate that individuals can keep active a limited number of items in primary memory during processing, unless processing blocks rehearsal, in which case retrieval occurs from secondary memory.

  18. Hydrothermal alteration styles in ancient and modern orogenic gold deposits, New Zealand

    International Nuclear Information System (INIS)

    Craw, D.; Upton, P.; MacKenzie, D.J.

    2009-01-01

    Orogenic hydrothermal systems in the South Island of New Zealand were active during Mesozoic and late Cenozoic collisional deformation and metamorphism of greywacke/schist terranes. Observations on the currently active mountain-building environment yield insights on processes occurring in the upper 5-15 km of the crust, and observations on an adjacent lithologically identical exhumed ancient mountain belt provide information on processes at 10-20 km in the crust. Hydrothermal fluids were mainly derived from metamorphic dehydration reactions and/or circulating topographically driven meteoric water in these mountain belts. Three geochemically and mineralogically different types of hydrothermal alteration and vein mineralisation occurred in these orogenic belts, and gold enrichment (locally economic) occurred in some examples of each of these three types. The first type of alteration involved fluids that were in or near chemical equilibrium with their greenschist facies host rocks. Fluid flow was controlled by discontinuous fractures, and by microshears and grain boundaries in host rocks, in zones from metres to hundreds of metres thick. Vein and alteration mineralogy was similar to that of the host rocks, and included calcite and chlorite. The second type of alteration occurred where the fluids were in distinct disequilibrium with the host rocks. Fracture permeability was important for fluid flow, but abundant host rock alteration occurred as well. The alteration zones were characterised by decomposition of chlorite and replacement by ankeritic carbonate in zones up to tens of metres thick. The mineralising fluid was deep-sourced and initially rock-equilibrated, with some meteoric input. The third type of mineralisation was controlled almost exclusively by fracture permeability, and host rock alteration was minor (centimetre scale). This mineralisation type commonly involved calcite and chlorite as vein and alteration minerals, and mineralisation fluids had a major

  19. Altered insula response to sweet taste processing after recovery from anorexia and bulimia nervosa.

    Science.gov (United States)

    Oberndorfer, Tyson A; Frank, Guido K W; Simmons, Alan N; Wagner, Angela; McCurdy, Danyale; Fudge, Julie L; Yang, Tony T; Paulus, Martin P; Kaye, Walter H

    2013-10-01

    Recent studies suggest that altered function of higher-order appetitive neural circuitry may contribute to restricted eating in anorexia nervosa and overeating in bulimia nervosa. This study used sweet tastes to interrogate gustatory neurocircuitry involving the anterior insula and related regions that modulate sensory-interoceptive-reward signals in response to palatable foods. Participants who had recovered from anorexia nervosa and bulimia nervosa were studied to avoid confounding effects of altered nutritional state. Functional MRI measured brain response to repeated tastes of sucrose and sucralose to disentangle neural processing of caloric and noncaloric sweet tastes. Whole-brain functional analysis was constrained to anatomical regions of interest. Relative to matched comparison women (N=14), women recovered from anorexia nervosa (N=14) had significantly diminished and women recovered from bulimia nervosa (N=14) had significantly elevated hemodynamic response to tastes of sucrose in the right anterior insula. Anterior insula response to sucrose compared with sucralose was exaggerated in the recovered group (lower in women recovered from anorexia nervosa and higher in women recovered from bulimia nervosa). The anterior insula integrates sensory reward aspects of taste in the service of nutritional homeostasis. One possibility is that restricted eating and weight loss occur in anorexia nervosa because of a failure to accurately recognize hunger signals, whereas overeating in bulimia nervosa could represent an exaggerated perception of hunger signals. This response may reflect the altered calibration of signals related to sweet taste and the caloric content of food and may offer a pathway to novel and more effective treatments.

  20. Alterations in protein kinase C activity and processing during zinc-deficiency-induced cell death.

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    Chou, Susan S; Clegg, Michael S; Momma, Tony Y; Niles, Brad J; Duffy, Jodie Y; Daston, George P; Keen, Carl L

    2004-10-01

    Protein kinases C (PKCs) are a family of serine/threonine kinases that are critical for signal transduction pathways involved in growth, differentiation and cell death. All PKC isoforms have four conserved domains, C1-C4. The C1 domain contains cysteine-rich finger-like motifs, which bind two zinc atoms. The zinc-finger motifs modulate diacylglycerol binding; thus, intracellular zinc concentrations could influence the activity and localization of PKC family members. 3T3 cells were cultured in zinc-deficient or zinc-supplemented medium for up to 32 h. Cells cultured in zinc-deficient medium had decreased zinc content, lowered cytosolic classical PKC activity, increased caspase-3 processing and activity, and reduced cell number. Zinc-deficient cytosols had decreased activity and expression levels of PKC-alpha, whereas PKC-alpha phosphorylation was not altered. Inhibition of PKC-alpha with Gö6976 had no effect on cell number in the zinc-deficient group. Proteolysis of the novel PKC family member, PKC-delta, to its 40-kDa catalytic fragment occurred in cells cultured in the zinc-deficient medium. Occurrence of the PKC-delta fragment in mitochondria was co-incident with caspase-3 activation. Addition of the PKC-delta inhibitor, rottlerin, or zinc to deficient medium reduced or eliminated proteolysis of PKC-delta, activated caspase-3 and restored cell number. Inhibition of caspase-3 processing by Z-DQMD-FMK (Z-Asp-Gln-Met-Asp-fluoromethylketone) did not restore cell number in the zinc-deficient group, but resulted in processing of full-length PKC-delta to a 56-kDa fragment. These results support the concept that intracellular zinc concentrations influence PKC activity and processing, and that zinc-deficiency-induced apoptosis occurs in part through PKC-dependent pathways.

  1. Altered dopamine signaling in naturally occurring maternal neglect.

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    Stephen C Gammie

    2008-04-01

    occurring neglect and that MaD1 mice are a useful model for understanding the basis of naturally occurring neglect.

  2. Altered BOLD response during inhibitory and error processing in adolescents with anorexia nervosa.

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    Christina Wierenga

    Full Text Available BACKGROUND: Individuals with anorexia nervosa (AN are often cognitively rigid and behaviorally over-controlled. We previously showed that adult females recovered from AN relative to healthy comparison females had less prefrontal activation during an inhibition task, which suggested a functional brain correlate of altered inhibitory processing in individuals recovered from AN. However, the degree to which these functional brain alterations are related to disease state and whether error processing is altered in AN individuals is unknown. METHODOLOGY/PRINCIPAL FINDINGS: In the current study, ill adolescent AN females (n = 11 and matched healthy comparison adolescents (CA with no history of an eating disorder (n = 12 performed a validated stop signal task (SST during functional magnetic resonance imaging (fMRI to explore differences in error and inhibitory processing. The groups did not differ on sociodemographic variables or on SST performance. During inhibitory processing, a significant group x difficulty (hard, easy interaction was detected in the right dorsal anterior cingulate cortex (ACC, right middle frontal gyrus (MFG, and left posterior cingulate cortex (PCC, which was characterized by less activation in AN compared to CA participants during hard trials. During error processing, a significant group x accuracy (successful inhibit, failed inhibit interaction in bilateral MFG and right PCC was observed, which was characterized by less activation in AN compared to CA participants during error (i.e., failed inhibit trials. CONCLUSION/SIGNIFICANCE: Consistent with our prior findings in recovered AN, ill AN adolescents, relative to CA, showed less inhibition-related activation within the dorsal ACC, MFG and PCC as inhibitory demand increased. In addition, ill AN adolescents, relative to CA, also showed reduced activation to errors in the bilateral MFG and left PCC. These findings suggest that altered prefrontal and cingulate activation during

  3. Process for altering the colour of hard stones

    International Nuclear Information System (INIS)

    Samoilovich, M.I.; Shaposhniko, A.A.; Turinge, A.P.; Vakhidov, S.A.; Nurullaev, Ergash.

    1981-01-01

    Process for altering the colour of hard stones and articles made with such stones, used in the jewellery trade, consisting in treating the hard stones in a neutron reactor and gamma particles accompanying them, whereby the treatment is performed with fast neutrons of at least 0.5 MeV, at integral doses of 5x10 15 to 1x10 18 neutrons/cm 2 , and gamma radiations, at integral doses of 5x10 6 to 1x10 9 R, at temperatures under 300 0 C [fr

  4. Water in the Early Solar System: Infrared Studies of Aqueously Altered and Minimally Processed Asteroids

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    McAdam, Margaret M.

    This thesis investigates connections between low albedo asteroids and carbonaceous chondrite meteorites using spectroscopy. Meteorites and asteroids preserve information about the early solar system including accretion processes and parent body processes active on asteroids at these early times. One process of interest is aqueous alteration. This is the chemical reaction between coaccreted water and silicates producing hydrated minerals. Some carbonaceous chondrites have experienced extensive interactions with water through this process. Since these meteorites and their parent bodies formed close to the beginning of the Solar System, these asteroids and meteorites may provide clues to the distribution, abundance and timing of water in the Solar nebula at these times. Chapter 2 of this thesis investigates the relationships between extensively aqueously altered meteorites and their visible, near and mid-infrared spectral features in a coordinated spectral-mineralogical study. Aqueous alteration is a parent body process where initially accreted anhydrous minerals are converted into hydrated minerals in the presence of coaccreted water. Using samples of meteorites with known bulk properties, it is possible to directly connect changes in mineralogy caused by aqueous alteration with spectral features. Spectral features in the mid-infrared are found to change continuously with increasing amount of hydrated minerals or degree of alteration. Building on this result, the degrees of alteration of asteroids are estimated in a survey of new asteroid data obtained from SOFIA and IRTF as well as archived the Spitzer Space Telescope data. 75 observations of 73 asteroids are analyzed and presented in Chapter 4. Asteroids with hydrated minerals are found throughout the main belt indicating that significant ice must have been present in the disk at the time of carbonaceous asteroid accretion. Finally, some carbonaceous chondrite meteorites preserve amorphous iron-bearing materials

  5. Various processes occurring in strong interactions between heavy ions: Compound nucleus formation, incomplete fusion, and quasifission

    International Nuclear Information System (INIS)

    Lefort, M.

    1975-01-01

    This paper deals with the problem of various deep processes occurring when two complex nuclei enter in collision. It is suggested that very deep inelastic processes may lead to either a compound nucleus or a composite system which shortly decays into two fission fragments (quasifission process). Particularly for heavy projectiles and targets, the predominant Coulomb potential inhibits the compound nucleus formation for low l waves. Then a critical angular momentum can be defined as the limit below which both processes (quasifission and compound nucleus formation) occur. For the heaviest nuclei, nearly all l waves below l) contribute to the quasifission phenomenon

  6. Altered lower extremity joint mechanics occur during the star excursion balance test and single leg hop after ACL-reconstruction in a collegiate athlete.

    Science.gov (United States)

    Samaan, Michael A; Ringleb, Stacie I; Bawab, Sebastian Y; Greska, Eric K; Weinhandl, Joshua T

    2018-03-01

    The effects of ACL-reconstruction on lower extremity joint mechanics during performance of the Star Excursion Balance Test (SEBT) and Single Leg Hop (SLH) are limited. The purpose of this study was to determine if altered lower extremity mechanics occur during the SEBT and SLH after ACL-reconstruction. One female Division I collegiate athlete performed the SEBT and SLH tasks, bilaterally, both before ACL injury and 27 months after ACL-reconstruction. Maximal reach, hop distances, lower extremity joint kinematics and moments were compared between both time points. Musculoskeletal simulations were used to assess muscle force production during the SEBT and SLH at both time points. Compared to the pre-injury time point, SEBT reach distances were similar in both limbs after ACL-reconstruction except for the max anterior reach distance in the ipsilateral limb. The athlete demonstrated similar hop distances, bilaterally, after ACL-reconstruction compared to the pre-injury time point. Despite normal functional performance during the SEBT and SLH, the athlete exhibited altered lower extremity joint mechanics during both of these tasks. These results suggest that measuring the maximal reach and hop distances for these tasks, in combination with an analysis of the lower extremity joint mechanics that occur after ACL-reconstruction, may help clinicians and researchers to better understand the effects of ACL-reconstruction on the neuromuscular system during the SEBT and SLH.

  7. Effects of Rhythmic and Melodic Alterations and Selected Musical Experiences on Rhythmic Processing.

    Science.gov (United States)

    Sink, Patricia E.

    1984-01-01

    Study showed that music listening habits and preferences and instrument training may affect ways an individual processes the multiple dimensions of rhythm. Apparent alterations in tempo, duration and pitch characteristics, rhythmic and melodic phrase patterning, and monotony may serve as organizers of rhythmic processing. (Author/RM)

  8. Study of Mururoa's basaltic massif alteration (French Polynesia): solid and fluid phases analysis and thermodynamical modeling

    International Nuclear Information System (INIS)

    Destrigneville, Christine

    1991-01-01

    The alteration processes occurring in the volcanics of Mururoa have been studied using petrological data on secondary minerals, chemical analyses of the interstitial fluids and isotopic analyses on both minerals and fluids. Chemical and isotopic exchanges were first modelled, then thermodynamical modeling characterized the chemical evolution during the alteration of the secondary assemblage and of the fluid. The main secondary sequences which have been observed in Mururoa volcanics result from the alteration occurring during the lavas setting. Two different processes have been evidenced. The first one is the deuteric alteration with the CO_2-rich magmatic fluid exsolved from the magma and trapped in the vesicles and the olivine microcracks of the lava intrusions. This alteration in a closed system is dominated by the solid phases when the CO_2 molar fraction in the fluid is higher than 0.25. The second process is the alteration of the lavas by seawater or a meteoric fluid. The basaltic flows present alteration assemblages composed of clay minerals and zeolites whose chemical composition has been forced by the fluid composition. Shallowness emissions of lavas result in completely argillized levels. The present interstitial fluids chemistry result from the percolation of seawater in the volcano. In the argillized levels the fluids have interacted with the clay minerals and their chemical compositions have been modified. The important chemical changes in the present interstitial fluids show that the present alteration in the volcano is higher than the fluids circulation. (author) [fr

  9. Alteration in fuel processing at Tokai Works of Mitsubishi Nuclear Fuel Co., Ltd

    International Nuclear Information System (INIS)

    1977-01-01

    The report of the Committee on Examination of Nuclear Fuel Safety to the Atomic Energy Commission of Japan concerning the alteration is given, which is attached to the reply from the commission to the prime minister, and its safety was confirmed. The alterations are installation of the storage for transport containers containing fuel assemblies, construction of radiation control and other buildings; and improvement and installation of the facilities for chemical-processing, pellet fabrication, fuel assembling, and storage. (Mori, K.)

  10. Quantification of diagenetic overprint processes deduced from fossil carbonate shells and laboratory-based hydrothermal alteration experiments

    Science.gov (United States)

    Griesshaber, Erika; Casella, Laura; Mavromatis, Vasileios; Dietzel, Martin; Immenhauser, Adrian; Schmahl, Wolfgang

    2016-04-01

    Benthic and nektonic marine biogenic carbonate archives represent the foundation of numerous studies aiming at reconstructions of past climate dynamics and environmental change. However, living organisms are not in thermodynamic equilibrium and create local chemical environments where physiologic processes such as biomineralization takes place. After the death of the organism the former physiologic disequilibrium conditions are not sustained any more and all biological tissues are altered by equilibration according to the surrounding environment: diagenesis. With increasing diagenetic alteration, the biogenic structure and fingerprint fades away and is replaced by inorganic features. Thus, recrystallization of organism-specific microstructure is a clear indicator for diagenetic overprint. Microstructural data, which mirror recrystallization, are of great value for interpreting geochemical proxies for paleo-environment reconstruction. Despite more than a century of research dealing with carbonate diagenesis, many of the controlling processes and factors are only understood in a qualitative manner. One of the main issues is that diagenetically altered carbonates are usually present as the product of a complex preceding diagenetic pathway with an unknown number of intermediate steps. In this contribution we present and discuss laboratory based alteration experiments with the aim to investigate time-series data sets in a controlled manner. We conducted hydrothermal alteration experiments with modern Arctica islandica (bivalvia) and Notosaria nigricans (brachiopoda) in order to mimic diagenetic overprint. We explore first the potential of electron backscattered diffraction (EBSD) measurements together with statistical data evaluation as a tool to quantify diagenetic alteration of carbonate skeletons. Subsequently, we compare microstructural patterns obtained from experimentally altered shell material with those of fossil specimens that have undergone variable degrees of

  11. Short Range-Ordered Minerals: Insight into Aqueous Alteration Processes on Mars

    Science.gov (United States)

    Ming, Douglas W.; Morris, R. V.; Golden, D. C.

    2011-01-01

    involved. The style of aqueous alteration (hydrolytic vs. acid sulfate) impacts which phases will form (e.g., oxides, oxysulfates, and oxyhydroxides). Knowledge on the formation processes of SRO phases in basaltic materials on Earth has allowed significant enhancement in our understanding of the aqueous processes at work on Mars. The 2011 Mars Science Laboratory (MSL) will provide an instrument suite that should improve our understanding of the mineralogical and chemical compositions of SRO phases. CheMin is an X-ray diffraction instrument that may provide broad X-ray diffraction peaks for SRO phases; e.g., broad peaks around 0.33 and 0.23 nm for allophane. Sample Analysis at Mars (SAM) heats samples and detects evolved gases of volatile-bearing phases including SRO phases (i.e., carbonates, sulfates, hydrated minerals). The Alpha Particle X-ray Spectrometer (APXS) and ChemCam element analyzers will provide chemical characterization of samples. The identification of SRO phases in surface materials on MSL will be challenging due to their nanocrystalline properties; their detection and identification will require utilizing the MSL instrument suite in concert. Ultimately, sample return missions will be required to definitively identify and fully characterize SRO minerals with state-of-the-art laboratory instrumentation back on Earth.

  12. Alteration of azurite into paratacamite at the St. Alessandro Church (Lasnigo, Italy

    Directory of Open Access Journals (Sweden)

    Giovanni Cavallo

    2009-01-01

    Full Text Available Many case studies report the alteration of the pigment azurite into paratacamite on wall paintings in Europe (for instance in Italy, Portugal, Austria. The analytical research performed on the 16th century wall paintings in the St. Alessandro church at Lasnigo (North Italy pointed out an irregular and inhomogeneous alteration of azurite. It is well known that azurite can transform into malachite when the humidity is high and in alkaline conditions and into basic copper chlorides (atacamite, paratacamite, clinoatacamite when solutions containing chlorine ions are present. X-ray diffraction allowed to refer the green compounds to paratacamite. The remaining surfaces painted with azurite do not reveal any trace of alteration despite of the presence of chlorine; a few traces of azurite have been found inside the direct incisions of the Crucifixion painted scene where the original blue pigment was completely lost. The microclimatic conditions seem to play an important role in the process in addition to the presence of water and chlorides. The surface where alteration occurs is the only one to be cyclically heated by the solar radiation, causing the transport of the solutions containing chlorides. The relationship between the environment and the chemical processes occurring represents an important issue to be developed.

  13. Synaptic plasticity, neural circuits, and the emerging role of altered short-term information processing in schizophrenia

    Science.gov (United States)

    Crabtree, Gregg W.; Gogos, Joseph A.

    2014-01-01

    Synaptic plasticity alters the strength of information flow between presynaptic and postsynaptic neurons and thus modifies the likelihood that action potentials in a presynaptic neuron will lead to an action potential in a postsynaptic neuron. As such, synaptic plasticity and pathological changes in synaptic plasticity impact the synaptic computation which controls the information flow through the neural microcircuits responsible for the complex information processing necessary to drive adaptive behaviors. As current theories of neuropsychiatric disease suggest that distinct dysfunctions in neural circuit performance may critically underlie the unique symptoms of these diseases, pathological alterations in synaptic plasticity mechanisms may be fundamental to the disease process. Here we consider mechanisms of both short-term and long-term plasticity of synaptic transmission and their possible roles in information processing by neural microcircuits in both health and disease. As paradigms of neuropsychiatric diseases with strongly implicated risk genes, we discuss the findings in schizophrenia and autism and consider the alterations in synaptic plasticity and network function observed in both human studies and genetic mouse models of these diseases. Together these studies have begun to point toward a likely dominant role of short-term synaptic plasticity alterations in schizophrenia while dysfunction in autism spectrum disorders (ASDs) may be due to a combination of both short-term and long-term synaptic plasticity alterations. PMID:25505409

  14. Chromosome alterations in the X-ray-induced transformants of cultured mouse cell line

    International Nuclear Information System (INIS)

    Kodama, Seiji; Komatsu, Kenshi; Okumura, Yutaka; Sasaki, M.S.

    1989-01-01

    Mouse m5S cells were subjected to soft X-ray irradiation. Twenty-four transformants were separated as indicators of focus formation. Two clones, cl.4103 and cl.6310, were chosen for the analysis of chromosome alterations in transformants. A parent strain, m5S/1M, served as the control. Anchorage independence (AG) was not detected in the control strain, irrespective of culture conditions and population doubling number (PDN). In the case of transformants, the frequency of AG was increased with increasing PDN for cl.4103, and was constant for cl.6310, irrespective of PDN. Karyotype of m5S/1M was 42, X, -Y, +der (6) t(6;13), t(8;8), +8, +15. In addition, -13, der(10) and -der(6)t(6;13), der(5), +mar occurred as karyotype alterations for cl.4103 and cl. 6310, respectively. The present experiment indicated that chromosome alterations secondary to primary alterations occur in a high frequency in the transforming process of X-ray irradiated cells, and that the secondary chromosome alterations result in selective proliferation of transformed clones. (Namekawa, K)

  15. Chromite alteration processes within Vourinos ophiolite

    Science.gov (United States)

    Grieco, Giovanni; Merlini, Anna

    2012-09-01

    The renewed interest in chromite ore deposits is directly related to the increase in Cr price ruled by international market trends. Chromite, an accessory mineral in peridotites, is considered to be a petrogenetic indicator because its composition reflects the degree of partial melting that the mantle experienced while producing the chromium spinel-bearing rock (Burkhard in Geochim Cosmochim Acta 57:1297-1306, 1993). However, the understanding of chromite alteration and metamorphic modification is still controversial (e.g. Evans and Frost in Geochim Cosmochim Acta 39:959-972, 1975; Burkhard in Geochim Cosmochim Acta 57:1297-1306, 1993; Oze et al. in Am J Sci 304:67-101, 2004). Metamorphic alteration leads to major changes in chromite chemistry and to the growth of secondary phases such as ferritchromite and chlorite. In this study, we investigate the Vourinos complex chromitites (from the mines of Rizo, Aetoraches, Xerolivado and Potamia) with respect to textural and chemical analyses in order to highlight the most important trend of alteration related to chromite transformation. The present study has been partially funded by the Aliakmon project in collaboration between the Public Power Corporation of Greece and Institute of Geology and Mineral Exploration of Kozani.

  16. Combined effects of hydrologic alteration and cyprinid fish in mediating biogeochemical processes in a Mediterranean stream.

    Science.gov (United States)

    Rubio-Gracia, Francesc; Almeida, David; Bonet, Berta; Casals, Frederic; Espinosa, Carmen; Flecker, Alexander S; García-Berthou, Emili; Martí, Eugènia; Tuulaikhuu, Baigal-Amar; Vila-Gispert, Anna; Zamora, Lluis; Guasch, Helena

    2017-12-01

    Flow regimes are important drivers of both stream community and biogeochemical processes. However, the interplay between community and biogeochemical responses under different flow regimes in streams is less understood. In this study, we investigated the structural and functional responses of periphyton and macroinvertebrates to different densities of the Mediterranean barbel (Barbus meridionalis, Cyprinidae) in two stream reaches differing in flow regime. The study was conducted in Llémena Stream, a small calcareous Mediterranean stream with high nutrient levels. We selected a reach with permanent flow (permanent reach) and another subjected to flow regulation (regulated reach) with periods of flow intermittency. At each reach, we used in situ cages to generate 3 levels of fish density. Cages with 10 barbels were used to simulate high fish density (>7indm -2 ); cages with open sides were used as controls (i.e. exposed to actual fish densities of each stream reach) thus having low fish density; and those with no fish were used to simulate the disappearance of fish that occurs with stream drying. Differences in fish density did not cause significant changes in periphyton biomass and macroinvertebrate density. However, phosphate uptake by periphyton was enhanced in treatments lacking fish in the regulated reach with intermittent flow but not in the permanent reach, suggesting that hydrologic alteration hampers the ability of biotic communities to compensate for the absence of fish. This study indicates that fish density can mediate the effects of anthropogenic alterations such as flow intermittence derived from hydrologic regulation on stream benthic communities and associated biogeochemical processes, at least in eutrophic streams. Copyright © 2017. Published by Elsevier B.V.

  17. Electrodermal Reactivity to Emotion Processing in Adults with Autistic Spectrum Disorders

    Science.gov (United States)

    Hubert, B. E.; Wicker, B.; Monfardini, E.; Deruelle, C.

    2009-01-01

    Although alterations of emotion processing are recognized as a core component of autism, the level at which alterations occur is still debated. Discrepant results suggest that overt assessment of emotion processing is not appropriate. In this study, skin conductance response (SCR) was used to examine covert emotional processes. Both behavioural…

  18. Long-Term Alterations in Neural and Endocrine Processes Induced by Motherhood

    Science.gov (United States)

    Bridges, Robert S.

    2015-01-01

    The reproductive experience of pregnancy, lactation and motherhood can significantly remodel the female’s biological state, affecting endocrine, neuroendocrine, neural, and immunological processes. The brain, pituitary gland, liver, thymus, and mammary tissue are among the structures that are modified by reproductive experience. The present review that focuses on rodent research, but also includes pertinent studies in sheep and other species, identifies specific changes in these processes brought about by the biological states of pregnancy, parturition, and lactation and how the components of reproductive experience contribute to the remodeling of the maternal brain and organ systems. Findings indicate that prior parity alters key circulating hormone levels and neural receptor gene expression. Moreover, reproductive experience results in modifications in neural processes and glial support. The possible role of pregnancy-induced neurogenesis is considered in the context of neuroplasticity and behavior, and the effects of reproductive experience on maternal memory, i.e. the retention of maternal behavior, together with anxiety and learning are presented. Together, these sets of findings support the concept that the neural and biological state of the adult female is significantly and dramatically altered on a long-term basis by the experiences of parity and motherhood. Remodeling of the maternal brain and other biological systems is posited to help facilitate adaptations to environmental/ecological challenges as the female raises young and ages. PMID:26388065

  19. Changes in Pain Modulation Occur Soon After Whiplash Trauma but are not Related to Altered Perception of Distorted Visual Feedback.

    Science.gov (United States)

    Daenen, Liesbeth; Nijs, Jo; Cras, Patrick; Wouters, Kristien; Roussel, Nathalie

    2014-09-01

    Widespread sensory hypersensitivity has been observed in acute whiplash associated disorders (WAD). Changes in descending pain modulation take part in central sensitization. However, endogenous pain modulation has never been investigated in acute WAD. Altered perception of distorted visual feedback has been observed in WAD. Both mechanisms (ie, pain modulation and perception of distorted visual feedback) may be different components of one integrated system orchestrated by the brain. This study evaluated conditioned pain modulation (CPM) in acute WAD. Secondly, we investigated whether changes in CPM are associated with altered perception of distorted visual feedback. Thirty patients with acute WAD, 35 patients with chronic WAD and 31 controls were subjected to an experiment evaluating CPM and a coordination task inducing visual mediated changes between sensory feedback and motor output. A significant CPM effect was observed in acute WAD (P = 0.012 and P = 0.006), which was significantly lower compared to controls (P = 0.004 and P = 0.020). No obvious differences in CPM were found between acute and chronic WAD (P = 0.098 and P = 0.041). Changes in CPM were unrelated to altered perception of distorted visual feedback (P > 0.01). Changes in CPM were observed in acute WAD, suggesting less efficient pain modulation. The results suggest that central pain and sensorimotor processing underlie distinctive mechanisms. © 2013 World Institute of Pain.

  20. MDMA alters emotional processing and facilitates positive social interaction.

    Science.gov (United States)

    Wardle, Margaret C; de Wit, Harriet

    2014-10-01

    ±3,4-Methylenedioxymethamphetamine (MDMA, "ecstasy") produces "prosocial" effects, such as feelings of empathy and closeness, thought to be important to its abuse and its value in psychotherapy. However, it is not fully understood how MDMA alters basic emotional processes to produce these effects, or whether it produces corresponding changes in actual social behavior. Here, we examined how MDMA affects perceptions of and responses to emotional expressions, and tested its effects on behavior during a social interaction. We also examined whether MDMA's prosocial effects related to a measure of abuse liability. Over three sessions, 36 healthy volunteers with previous ecstasy use received MDMA (0.75, 1.5 mg/kg) and placebo under double-blind conditions. We measured (i) mood and cardiovascular effects, (ii) perception of and psychophysiological responses to emotional expressions, (iii) use of positive and negative words in a social interaction, and (iv) perceptions of an interaction partner. We then tested whether these effects predicted desire to take the drug again. MDMA slowed perception of angry expressions, increased psychophysiological responses to happy expressions, and increased positive word use and perceptions of partner empathy and regard in a social interaction. These effects were not strongly related to desire to take the drug again. MDMA alters basic emotional processes by slowing identification of negative emotions and increasing responses to positive emotions in others. Further, it positively affects behavior and perceptions during actual social interaction. These effects may contribute to the efficacy of MDMA in psychotherapy, but appear less closely related to its abuse potential.

  1. Tank waste remediation system optimized processing strategy with an altered treatment scheme

    International Nuclear Information System (INIS)

    Slaathaug, E.J.

    1996-03-01

    This report provides an alternative strategy evolved from the current Hanford Site Tank Waste Remediation System (TWRS) programmatic baseline for accomplishing the treatment and disposal of the Hanford Site tank wastes. This optimized processing strategy with an altered treatment scheme performs the major elements of the TWRS Program, but modifies the deployment of selected treatment technologies to reduce the program cost. The present program for development of waste retrieval, pretreatment, and vitrification technologies continues, but the optimized processing strategy reuses a single facility to accomplish the separations/low-activity waste (LAW) vitrification and the high-level waste (HLW) vitrification processes sequentially, thereby eliminating the need for a separate HLW vitrification facility

  2. Congenital heart malformations induced by hemodynamic altering surgical interventions

    Directory of Open Access Journals (Sweden)

    Madeline eMidgett

    2014-08-01

    Full Text Available Embryonic heart formation results from a dynamic interplay between genetic and environmental factors. Blood flow during early embryonic stages plays a critical role in heart development, as interactions between flow and cardiac tissues generate biomechanical forces that modulate cardiac growth and remodeling. Normal hemodynamic conditions are essential for proper cardiac development, while altered blood flow induced by surgical manipulations in animal models result in heart defects similar to those seen in humans with congenital heart disease. This review compares the altered hemodynamics, changes in tissue properties, and cardiac defects reported after common surgical interventions that alter hemodynamics in the early chick embryo, and shows that interventions produce a wide spectrum of cardiac defects. Vitelline vein ligation and left atrial ligation decrease blood pressure and flow; and outflow tract banding increases blood pressure and flow velocities. These three surgical interventions result in many of the same cardiac defects, which indicate that the altered hemodynamics interfere with common looping, septation and valve formation processes that occur after intervention and that shape the four-chambered heart. While many similar defects develop after the interventions, the varying degrees of hemodynamic load alteration among the three interventions also result in varying incidence and severity of cardiac defects, indicating that the hemodynamic modulation of cardiac developmental processes is strongly dependent on hemodynamic load.

  3. Development of potentiometric equipment for the identification of altered dry-cured hams: A preliminary study.

    Science.gov (United States)

    Girón, Joel; Gil-Sánchez, Luís; García-Breijo, Eduardo; Pagán, M Jesús; Barat, José M; Grau, Raúl

    2015-08-01

    Microbiological contamination in dry-cured ham can occur in the early stages of the process, a large number of microorganisms involved in spoilage can produce alterations in the product. These include non-common odours, which are detected at the end of the process by a procedure called "cala", consisting of a sharp instrument punctured in every ham; this is smelled by an expert taster, who classifies hams as good and altered hams. An electronic device would be suitable for this process given the large amount of hams. The present research aims to develop objective equipment based on the potentiometry technique that identifies altered hams. A probe was developed, containing silver, nickel and copper electrodes, and was employed to classify altered and unaltered hams prior to classification by a tester. The results shown lower Ag and higher Cu potential values for altered hams. The differences in potentiometric response reveal a classification model, although further studies are required to obtain a reliable classification model. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Identification of networks of co-occurring, tumor-related DNA copy number changes using a genome-wide scoring approach.

    Directory of Open Access Journals (Sweden)

    Christiaan Klijn

    2010-01-01

    Full Text Available Tumorigenesis is a multi-step process in which normal cells transform into malignant tumors following the accumulation of genetic mutations that enable them to evade the growth control checkpoints that would normally suppress their growth or result in apoptosis. It is therefore important to identify those combinations of mutations that collaborate in cancer development and progression. DNA copy number alterations (CNAs are one of the ways in which cancer genes are deregulated in tumor cells. We hypothesized that synergistic interactions between cancer genes might be identified by looking for regions of co-occurring gain and/or loss. To this end we developed a scoring framework to separate truly co-occurring aberrations from passenger mutations and dominant single signals present in the data. The resulting regions of high co-occurrence can be investigated for between-region functional interactions. Analysis of high-resolution DNA copy number data from a panel of 95 hematological tumor cell lines correctly identified co-occurring recombinations at the T-cell receptor and immunoglobulin loci in T- and B-cell malignancies, respectively, showing that we can recover truly co-occurring genomic alterations. In addition, our analysis revealed networks of co-occurring genomic losses and gains that are enriched for cancer genes. These networks are also highly enriched for functional relationships between genes. We further examine sub-networks of these networks, core networks, which contain many known cancer genes. The core network for co-occurring DNA losses we find seems to be independent of the canonical cancer genes within the network. Our findings suggest that large-scale, low-intensity copy number alterations may be an important feature of cancer development or maintenance by affecting gene dosage of a large interconnected network of functionally related genes.

  5. Altered Amygdala Development and Fear Processing in Prematurely Born Infants

    Science.gov (United States)

    Cismaru, Anca Liliana; Gui, Laura; Vasung, Lana; Lejeune, Fleur; Barisnikov, Koviljka; Truttmann, Anita; Borradori Tolsa, Cristina; Hüppi, Petra S.

    2016-01-01

    might be linked to alterations in white matter connectivity reported in premature infants. Moreover, our data suggests that such alterations might affect infants’ fear-processing capabilities. PMID:27242451

  6. Numerical Validation of Chemical Compositional Model for Wettability Alteration Processes

    Science.gov (United States)

    Bekbauov, Bakhbergen; Berdyshev, Abdumauvlen; Baishemirov, Zharasbek; Bau, Domenico

    2017-12-01

    Chemical compositional simulation of enhanced oil recovery and surfactant enhanced aquifer remediation processes is a complex task that involves solving dozens of equations for all grid blocks representing a reservoir. In the present work, we perform a numerical validation of the newly developed mathematical formulation which satisfies the conservation laws of mass and energy and allows applying a sequential solution approach to solve the governing equations separately and implicitly. Through its application to the numerical experiment using a wettability alteration model and comparisons with existing chemical compositional model's numerical results, the new model has proven to be practical, reliable and stable.

  7. Geothermal alteration of clay minerals and shales: diagenesis

    Energy Technology Data Exchange (ETDEWEB)

    Weaver, C.E.

    1979-07-01

    The objective of this report is to perform a critical review of the data on the mineral and chemical alterations that occur during diagenesis and low-grade metamorphism of shale and other clay-rich rocks - conditions similar to those expected from emplacement of heat-producing radioactive waste in a geologic repository. The conclusions drawn in this document are that the following type of alterations could occur: smectite alteration, ion mobilization, illitic shales, kaolinite reactions, chlorite reactions, organic reactions, paleotemperatures, low temperature shales, high temperature shales, and phase equilibrium changes.

  8. Geothermal alteration of clay minerals and shales: diagenesis

    International Nuclear Information System (INIS)

    Weaver, C.E.

    1979-07-01

    The objective of this report is to perform a critical review of the data on the mineral and chemical alterations that occur during diagenesis and low-grade metamorphism of shale and other clay-rich rocks - conditions similar to those expected from emplacement of heat-producing radioactive waste in a geologic repository. The conclusions drawn in this document are that the following type of alterations could occur: smectite alteration, ion mobilization, illitic shales, kaolinite reactions, chlorite reactions, organic reactions, paleotemperatures, low temperature shales, high temperature shales, and phase equilibrium changes

  9. Alteration of bioelectrically-controlled processes in the embryo: a teratogenic mechanism for anticonvulsants.

    Science.gov (United States)

    Hernández-Díaz, Sonia; Levin, Michael

    2014-08-01

    Maternal use of anticonvulsants during the first trimester of pregnancy has been associated with an elevated risk of major congenital malformations in the offspring. Whether the increased risk is caused by the specific pharmacological mechanisms of certain anticonvulsants, the underlying epilepsy, or common genetic or environmental risk factors shared by epilepsy and malformations has been controversial. We hypothesize that anticonvulsant therapies during pregnancy that attain more successful inhibition of neurotransmission might lead to both better seizure control in the mother and stronger alteration of bioelectrically-controlled processes in the embryo that result in structural malformations. We propose that development of pharmaceuticals that do not alter cell resting transmembrane voltage levels could result in safer drugs. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Ca-Fe and Alkali-Halide Alteration of an Allende Type B CAI: Aqueous Alteration in Nebular or Asteroidal Settings

    Science.gov (United States)

    Ross, D. K.; Simon, J. I.; Simon, S. B.; Grossman, L.

    2012-01-01

    Ca-Fe and alkali-halide alteration of CAIs is often attributed to aqueous alteration by fluids circulating on asteroidal parent bodies after the various chondritic components have been assembled, although debate continues about the roles of asteroidal vs. nebular modification processes [1-7]. Here we report de-tailed observations of alteration products in a large Type B2 CAI, TS4 from Allende, one of the oxidized subgroup of CV3s, and propose a speculative model for aqueous alteration of CAIs in a nebular setting. Ca-Fe alteration in this CAI consists predominantly of end-member hedenbergite, end-member andradite, and compositionally variable, magnesian high-Ca pyroxene. These phases are strongly concentrated in an unusual "nodule" enclosed within the interior of the CAI (Fig. 1). The Ca, Fe-rich nodule superficially resembles a clast that pre-dated and was engulfed by the CAI, but closer inspection shows that relic spinel grains are enclosed in the nodule, and corroded CAI primary phases interfinger with the Fe-rich phases at the nodule s margins. This CAI also contains abundant sodalite and nepheline (alkali-halide) alteration that occurs around the rims of the CAI, but also penetrates more deeply into the CAI. The two types of alteration (Ca-Fe and alkali-halide) are adjacent, and very fine-grained Fe-rich phases are associated with sodalite-rich regions. Both types of alteration appear to be replacive; if that is true, it would require substantial introduction of Fe, and transport of elements (Ti, Al and Mg) out of the nodule, and introduction of Na and Cl into alkali-halide rich zones. Parts of the CAI have been extensively metasomatized.

  11. On permission of alteration of business of processing nuclear fuel materials in Japan Nuclear Fuel Co., Ltd

    International Nuclear Information System (INIS)

    1985-01-01

    The Nuclear Safety Commission sent the report on this matter to the Prime Minister on December 13, 1984, upon having received the report from the Committee on Examination of Nuclear Fuel Safety and after the deliberation. It was recognized that the technical capability of the applicant is appropriate. Also it was judged that the safety after the alteration of the processing facilities can be ensured. The alteration of the processing facilities is as follows. According to the revision of production, the maximum processing capacity is changed from 750 t U/year to 640 t U/year, and accompanying this change, the maximum processing capacity of the assembling facilities is changed from 850 t U/year to 640 t U/year. The installation of the assembling plant with 295 t U/year capacity in No.2 shop is abolished, and the capacity of the assembling plant in No.1 shop is increased from 555 t U/year to 640 t U/year. No.2 fuel assembly preserving area is set up in No.2 shop, and its capacity is changed from 24 t UO 2 to 170 t UO 2 . By the examination of criticality control and radiation control, the safety of this alteration was confirmed. (Kako, I.)

  12. Aqueous Alteration of Carbonaceous Chondrites: New Insights from Comparative Studies of Two Unbrecciated CM2 Chondrites, Y 791198 and ALH 81002

    Science.gov (United States)

    Chizmadia, L. J.; Brearley, A. J.

    2004-01-01

    Carbonaceous chondrites are an important resource for understanding the physical and chemical conditions in the early solar system. In particular, a long-standing question concerns the role of water in the cosmochemical evolution of carbonaceous chondrites. It is well established that extensive hydration of primary nebular phases occurred in the CM and CI chondrites, but the location where this alteration occurred remains controversial. In the CM2 chondrites, hydration formed secondary phases such as serpentine, tochilinite, pentlandite, carbonate and PCP. There are several textural observations which suggest that alteration occurred before the accretion of the final CM parent asteroid, i.e. preaccretionary alteration. Conversely, there is a significant body of evidence that supports parent-body alteration. In order to test these two competing hypotheses further, we studied two CM chondrites, Y-791198 and ALH81002, two meteorites that exhibit widely differing degrees of aqueous alteration. In addition, both meteorites have primary accretionary textures, i.e. experienced minimal asteroidal brecciation. Brecciation significantly complicates the task of unraveling alteration histories, mixing components that have been altered to different degrees from different locations on the same asteroidal parent body. Alteration in Y-791198 is mostly confined to chondrule mesostases, FeNi metal and fine-grained matrix and rims. In comparison, the primary chondrule silicates in ALH81002 have undergone extensive replacement by secondary hydrous phases. This study focuses on compositional and textural relationships between chondrule mesostasis and the associated rim materials. Our hypothesis is: both these components are highly susceptible to aqueous alteration and should be sensitive recorders of the alteration process. For parent body alteration, we expect systematic coupled mineralogical and compositional changes in rims and altered mesostasis, as elemental exchange between these

  13. Itataia's phosphorous-uraniferous deposit - Alteration and argilization influence in physical processing of the mineralized lithologies

    International Nuclear Information System (INIS)

    Rosa, C.V.

    1986-01-01

    This study was developed by NUCLEBRAS, firstly defining the quality and quantity of the Itataia ore body untill the 480 m level of the future pit, considering the lithological types, the P 2 O 5 and U 3 O 8 contents and the alteration and argillization of the rocks. The following step was to establish the physicochemical character of the mineralized lithologies according to the phases of alteration/argillization. Finally it was compared the results of these two stages with the results of the pilot treatment, related to the gangue in the phosphoric acid concentrate. The method showed the difficulties in each host rock, differently altered/argillized for future process and allowed to the identification of seven types of material to supply the Itataia pilot plant. (author) [pt

  14. Permission of the alteration in nuclear fuel material processing business in the Kumatori Works of Nuclear Fuel Industries, Ltd. (report)

    International Nuclear Information System (INIS)

    1982-01-01

    A report by the Nuclear Safety Commission to the Prime Minister concerning the permission of the alteration in nuclear fuel material processing business in the Kumatori Works, Nuclear Fuel Industries Ltd., was presented. The technical capability of NFI and the safety of the business alteration were confirmed. The items of the safety examination concerning the alteration, made by the Committee on Examination of Nuclear Fuel Safety of NSC, are as follows: the aseismic design and fire prevention measures of the No.2 processing building and the No.3 waste storage building to be newly installed; criticality control concerning the No.2 processing building; the release control of gaseous and liquid wastes; the management of solid wastes; radiation control; the exposure dose of general public. (J.P.N.)

  15. Chemical and Mineralogical Features of Smectite from the Morron de Mateo Bentonite Deposit (Cabo de Gata, Almeria) in Relation to the Parent Rocks and the Alteration Processes Occurred After the Bentonite Formation: Analogies and Implications for the Engineered Clayey Barrier of a Deep Geological Rad waste Repository

    International Nuclear Information System (INIS)

    Pelayo, M.; Labajo, M. A.; Garcia Romero, L.; Perez del Villar, L.

    2009-01-01

    The Morron de Mateo bentonite deposit is being studied as a natural analogue of the thermal and geochemical effects on the clayey barrier of a Deep Geological Rad waste Repository (DGRR) after its closure, in relation to the radioactive decay of the fission products and the container corrosion. This bentonite deposit and their host rocks were intruded by a rhyodacitic volcanic dome that induced a hydrothermal metasomatic process affecting the bioclastic calcarenite beds close to the dome. Bentonite from the NE sector of the deposit have been chemically and mineralogically characterized. Pyroclastic rocks (white tuffs), epyclastic rocks (mass flow) and andesitic breccia all of them hydrothermally altered, have been studied at the site. Samples are composed of feldspars, quartz and amphybols, as inherited minerals, and phyllosilicates, zeolites, crystoballite and calcite, as new formed minerals. White tuffs have the highest phyllosilicate contents, mainly dioctahedral smectite of montmorillonite type. Epyclastic rocks and andesitic breccia have a highest proportion of inherited minerals, the new formed phillosilicates being di octahedral smectite of beidellite type and an ordered interlayer chlorite/smectite mineral, of corrensite type. Smectite from the epyclastic rocks have higher Fe and Mg contents and chemical variability, as a consequence of nature of their parent rocks. The presence of corrensite in the epyclastic rocks suggests that in the Morron de Mateo area a propilitic alteration process occurred after bentonite formation, which transformed Fe-Mg-rich smectite into corrensite. This transformation was probably favoured by the sub volcanic intrusion, which also produced a temperature increase in the geological media and a supply of Fe-Mg-rich solutions, which also were the responsible for the metasomatic transformations observed in the calcarenite beds. (Author) 57 refs

  16. The encounter and analysis of naturally occurring radionuclides in gas and oil production and processing

    International Nuclear Information System (INIS)

    Hartog, F.A.; Jonkers, G.; Knaepen, W.A.I.

    1996-01-01

    As a result of oil and gas production, radioactive daughter elements from the uranium and thorium decay series can be mobilized and transported away from the reservoir. Due to changes in flow regime, temperature, pressure or chemical environment NORs (Naturally Occurring Radionuclides) may build up in products, by-products or waste streams from gas and oil production and processing facilities. Products containing NORs are commonly denoted by the acronym NORM (Naturally Occurring Radioactive Materials). Main topics of this paper are: E and P (Exploration and Production) NORM characteristics; incentives for NORM analysis; NORM analysis; interlaboratory test programme; analysis techniques; results and conclusions of the test programme. 4 figs., 2 tabs

  17. Alteration of consciousness in focal epilepsy: the global workspace alteration theory.

    Science.gov (United States)

    Bartolomei, Fabrice; McGonigal, Aileen; Naccache, Lionel

    2014-01-01

    Alteration of consciousness (AOC) is an important clinical manifestation of partial seizures that greatly impacts the quality of life of patients with epilepsy. Several theories have been proposed in the last fifty years. An emerging concept in neurology is the global workspace (GW) theory that postulates that access to consciousness (from several sensorial modalities) requires transient coordinated activity from associative cortices, in particular the prefrontal cortex and the posterior parietal associative cortex. Several lines of evidence support the view that partial seizures alter consciousness through disturbance of the GW. In particular, a nonlinear relation has been shown between excess of synchronization in the GW regions and the degree of AOC. Changes in thalamocortical synchrony occurring during the spreading of the ictal activity seem particularly involved in the mechanism of altered consciousness. This link between abnormal synchrony and AOC offers new perspectives in the treatment of the AOC since means of decreasing consciousness alteration in seizures could improve patients' quality of life. © 2013.

  18. Composition and microstructure alteration of triticale grain surface after processing by enzymes of cellulase complex

    Directory of Open Access Journals (Sweden)

    Elena Kuznetsova

    2016-01-01

    Full Text Available It is found that the pericarp tissue of grain have considerable strength and stiffness, that has an adverse effect on quality of whole-grain bread. Thereby, there exists the need for preliminary chemical and biochemical processing of durable cell walls before industrial use. Increasingly used in the production of bread finds an artificial hybrid of the traditional grain crops of wheat and rye - triticale, grain which has high nutritional value. The purpose of this research was to evaluate the influence of cellulose complex (Penicillium canescens enzymes on composition and microstructure alteration of triticale grain surface, for grain used in baking. Triticale grain was processed by cellulolytic enzyme preparations with different composition (producer is Penicillium canescens. During experiment it is found that triticale grain processing by enzymes of cellulase complex leads to an increase in the content of water-soluble pentosans by 36.3 - 39.2%. The total amount of low molecular sugars increased by 3.8 - 10.5 %. Studies show that under the influence of enzymes the microstructure of the triticale grain surface is changing. Microphotographs characterizing grain surface structure alteration in dynamic (every 2 hours during 10 hours of substrate hydrolysis are shown. It is found that the depth and direction of destruction process for non-starch polysaccharides of grain integument are determined by the composition of the enzyme complex preparation and duration of exposure. It is found, that xylanase involved in the modification of hemicelluloses fiber having both longitudinal and radial orientation. Hydrolysis of non-starch polysaccharides from grain shells led to increase of antioxidant activity. Ferulic acid was identified in alcoholic extract of triticale grain after enzymatic hydrolysis under the influence of complex preparation containing cellulase, xylanase and β-glucanase. Grain processing by independent enzymes containing in complex

  19. A social network analysis approach to alcohol use and co-occurring addictive behavior in young adults.

    Science.gov (United States)

    Meisel, Matthew K; Clifton, Allan D; MacKillop, James; Goodie, Adam S

    2015-12-01

    The current study applied egocentric social network analysis (SNA) to investigate the prevalence of addictive behavior and co-occurring substance use in college students' networks. Specifically, we examined individuals' perceptions of the frequency of network members' co-occurring addictive behavior and investigated whether co-occurring addictive behavior is spread evenly throughout networks or is more localized in clusters. We also examined differences in network composition between individuals with varying levels of alcohol use. The study utilized an egocentric SNA approach in which respondents ("egos") enumerated 30 of their closest friends, family members, co-workers, and significant others ("alters") and the relations among alters listed. Participants were 281 undergraduates at a large university in the Southeastern United States. Robust associations were observed among the frequencies of gambling, smoking, drinking, and using marijuana by network members. We also found that alters tended to cluster together into two distinct groups: one cluster moderate-to-high on co-occurring addictive behavior and the other low on co-occurring addictive behavior. Lastly, significant differences were present when examining egos' perceptions of alters' substance use between the networks of at-risk, light, and nondrinkers. These findings provide empirical evidence of distinct clustering of addictive behavior among young adults and suggest the promise of social network-based interventions for this cohort. Copyright © 2015. Published by Elsevier Ltd.

  20. Alterations of monetary reward and punishment processing in chronic cannabis users: an FMRI study.

    Science.gov (United States)

    Enzi, Björn; Lissek, Silke; Edel, Marc-Andreas; Tegenthoff, Martin; Nicolas, Volkmar; Scherbaum, Norbert; Juckel, Georg; Roser, Patrik

    2015-01-01

    Alterations in reward and punishment processing have been reported in adults suffering from long-term cannabis use. However, previous findings regarding the chronic effects of cannabis on reward and punishment processing have been inconsistent. In the present study, we used functional magnetic resonance imaging (fMRI) to reveal the neural correlates of reward and punishment processing in long-term cannabis users (n = 15) and in healthy control subjects (n = 15) with no history of drug abuse. For this purpose, we used the well-established Monetary Incentive Delay (MID) task, a reliable experimental paradigm that allows the differentiation between anticipatory and consummatory aspects of reward and punishment processing. Regarding the gain anticipation period, no significant group differences were observed. In the left caudate and the left inferior frontal gyrus, cannabis users were - in contrast to healthy controls - not able to differentiate between the conditions feedback of reward and control. In addition, cannabis users showed stronger activations in the left caudate and the bilateral inferior frontal gyrus following feedback of no punishment as compared to healthy controls. We interpreted these deficits in dorsal striatal functioning as altered stimulus-reward or action-contingent learning in cannabis users. In addition, the enhanced lateral prefrontal activation in cannabis users that is related to non-punishing feedback may reflect a deficit in emotion regulation or cognitive reappraisal in these subjects.

  1. Alterations of monetary reward and punishment processing in chronic cannabis users: an FMRI study.

    Directory of Open Access Journals (Sweden)

    Björn Enzi

    Full Text Available Alterations in reward and punishment processing have been reported in adults suffering from long-term cannabis use. However, previous findings regarding the chronic effects of cannabis on reward and punishment processing have been inconsistent. In the present study, we used functional magnetic resonance imaging (fMRI to reveal the neural correlates of reward and punishment processing in long-term cannabis users (n = 15 and in healthy control subjects (n = 15 with no history of drug abuse. For this purpose, we used the well-established Monetary Incentive Delay (MID task, a reliable experimental paradigm that allows the differentiation between anticipatory and consummatory aspects of reward and punishment processing. Regarding the gain anticipation period, no significant group differences were observed. In the left caudate and the left inferior frontal gyrus, cannabis users were - in contrast to healthy controls - not able to differentiate between the conditions feedback of reward and control. In addition, cannabis users showed stronger activations in the left caudate and the bilateral inferior frontal gyrus following feedback of no punishment as compared to healthy controls. We interpreted these deficits in dorsal striatal functioning as altered stimulus-reward or action-contingent learning in cannabis users. In addition, the enhanced lateral prefrontal activation in cannabis users that is related to non-punishing feedback may reflect a deficit in emotion regulation or cognitive reappraisal in these subjects.

  2. Anticonvulsants Teratogenic Mechanism Involves Alteration of Bioelectrically-controlled Processes in the Embryo. A hypothesis

    Science.gov (United States)

    Hernández-Díaz, Sonia; Levin, Michael

    2014-01-01

    Maternal use of anticonvulsants during the first trimester of pregnancy has been associated with an elevated risk of major congenital malformations in the offspring. Whether the increased risk is caused by the specific pharmacological mechanisms of certain anticonvulsants, the underlying epilepsy, or common genetic or environmental risk factors shared by epilepsy and malformations is controversial. We hypothesize that anticonvulsant therapies during pregnancy that attain more successful inhibition of neurotransmission might lead to both better seizure control in the mother and stronger alteration of bioelectrically-controlled processes in the embryo that result in structural malformations. If our theory were correct, development of pharmaceuticals that do not alter cell resting transmembrane voltage levels could result in safer drugs. PMID:24815983

  3. Chemical Changes in Carbohydrates Produced by Thermal Processing.

    Science.gov (United States)

    Hoseney, R. Carl

    1984-01-01

    Discusses chemical changes that occur in the carbohydrates found in food products when these products are subjected to thermal processing. Topics considered include browning reactions, starch found in food systems, hydrolysis of carbohydrates, extrusion cooking, processing of cookies and candies, and alterations in gums. (JN)

  4. Thermal alterations of organic matter in coal wastes from Upper Silesia, Poland

    Science.gov (United States)

    Misz-Kennan, Magdalena

    2010-01-01

    lacking suggests that they originated elsewhere and subsequently migrated through the dump piles. During their migration, the compounds fractionated, were adsorbed on minerals and/or interacted. The absence of alkenes, and of other unsaturated organic compounds, may reflect primary diagenetic processes that occurred in coals and coal shales during burial and/or organic matter type. Their absence may also be a consequence of heating that lasted many years, hydropyrolysis, and/or the participation of minerals in the reactions occurring within the dumps. The wastes contain compounds typical of organic matter of unaltered kerogen III type and the products of pyrolytic processes, and mixtures of both. In some wastes, organic compounds are completely absent having been destroyed by severe heating. The distributions of n-alkanes in many samples are typical of pyrolysates. In some wastes, narrow n-alkane distributions reflect their generation over small temperature ranges. In others, wider distributions point to greater temperature ranges. Other wastes contain n-alkane distributions typical of unaltered coal and high pristane content or mixtures of pyrolysates and unaltered waste material. The wastes also contain significant amounts of final αβ hopanes. Polycyclic aromatic hydrocarbons are represented only by two- to five-ring compounds as is typical of the thermal alteration of hard coal. Correlations between the degree of organic matter alteration and the relative contents of individual PAHs and hopanes and geochemical indicators of thermal alteration are generally poor. The properties of the organic matter (its composition and rank), temperature fluctuations within the dumps, migration of organic compounds and mineral involvement are probably responsible for this. The processes taking place in coal waste dumps undergoing self-heating and self-combustion are complicated; they are very difficult to estimate and define. The methods of organic petrology and geochemistry give

  5. On the Behavior of Phosphorus During the Aqueous Alteration of CM2 Carbonaceous Chondrites

    Science.gov (United States)

    Brearley, Adrian J.; Chizmadia, Lysa J.

    2005-01-01

    During the earliest period of solar system formation, water played an important role in the evolution of primitive dust, both after accretion of planetesimals and possible before accretion within the protoplanetary disk. Many chondrites show evidence of variable degrees of aqueous alteration, the CM2 chondrites being among the most studied [1]. This group of chondrites is characterized by mineral assemblages of both primary and secondary alteration phases. Hence, these meteorites retain a particularly important record of the reactions that occurred between primary high temperature nebular phases and water. Studies of these chondrites can provide information on the conditions and environments of aqueous alteration and the mobility of elements during alteration. This latter question is at the core of a debate concerning the location of aqueous alteration, i.e. whether alteration occurred predominantly within a closed system after accretion (parent body alteration) or whether some degree of alteration occurred within the solar nebula or on ephemeral protoplanetary bodies prior to accretion. At the core of the parent body alteration model is the hypothesis that elemental exchange between different components, principally chondrules and matrix, must have occurred. chondrules and matrix, must have occurred. In this study, we focus on the behavior of the minor element, phosphorus. This study was stimulated by observations of the behavior of P during the earliest stages of alteration in glassy mesostasis in type II chondrules in CR chondrites and extends the preliminary observations of on Y791198 to other CM chondrites.

  6. Cryotherapy Reduces Inflammatory Response Without Altering Muscle Regeneration Process and Extracellular Matrix Remodeling of Rat Muscle.

    Science.gov (United States)

    Vieira Ramos, Gracielle; Pinheiro, Clara Maria; Messa, Sabrina Peviani; Delfino, Gabriel Borges; Marqueti, Rita de Cássia; Salvini, Tania de Fátima; Durigan, Joao Luiz Quagliotti

    2016-01-04

    The application of cryotherapy is widely used in sports medicine today. Cooling could minimize secondary hypoxic injury through the reduction of cellular metabolism and injury area. Conflicting results have also suggested cryotherapy could delay and impair the regeneration process. There are no definitive findings about the effects of cryotherapy on the process of muscle regeneration. The aim of the present study was to evaluate the effects of a clinical-like cryotherapy on inflammation, regeneration and extracellular matrix (ECM) remodeling on the Tibialis anterior (TA) muscle of rats 3, 7 and 14 days post-injury. It was observed that the intermittent application of cryotherapy (three 30-minute sessions, every 2 h) in the first 48 h post-injury decreased inflammatory processes (mRNA levels of TNF-α, NF-κB, TGF-β and MMP-9 and macrophage percentage). Cryotherapy did not alter regeneration markers such as injury area, desmin and Myod expression. Despite regulating Collagen I and III and their growth factors, cryotherapy did not alter collagen deposition. In summary, clinical-like cryotherapy reduces the inflammatory process through the decrease of macrophage infiltration and the accumulation of the inflammatory key markers without influencing muscle injury area and ECM remodeling.

  7. Cognitive alterations in motor imagery process after left hemispheric ischemic stroke.

    Directory of Open Access Journals (Sweden)

    Jing Yan

    Full Text Available BACKGROUND: Motor imagery training is a promising rehabilitation strategy for stroke patients. However, few studies had focused on the neural mechanisms in time course of its cognitive process. This study investigated the cognitive alterations after left hemispheric ischemic stroke during motor imagery task. METHODOLOGY/PRINCIPAL FINDINGS: Eleven patients with ischemic stroke in left hemisphere and eleven age-matched control subjects participated in mental rotation task (MRT of hand pictures. Behavior performance, event-related potential (ERP and event-related (desynchronization (ERD/ERS in beta band were analyzed to investigate the cortical activation. We found that: (1 The response time increased with orientation angles in both groups, called "angle effect", however, stoke patients' responses were impaired with significantly longer response time and lower accuracy rate; (2 In early visual perceptual cognitive process, stroke patients showed hypo-activations in frontal and central brain areas in aspects of both P200 and ERD; (3 During mental rotation process, P300 amplitude in control subjects decreased while angle increased, called "amplitude modulation effect", which was not observed in stroke patients. Spatially, patients showed significant lateralization of P300 with activation only in contralesional (right parietal cortex while control subjects showed P300 in both parietal lobes. Stroke patients also showed an overall cortical hypo-activation of ERD during this sub-stage; (4 In the response sub-stage, control subjects showed higher ERD values with more activated cortical areas particularly in the right hemisphere while angle increased, named "angle effect", which was not observed in stroke patients. In addition, stroke patients showed significant lower ERD for affected hand (right response than that for unaffected hand. CONCLUSIONS/SIGNIFICANCE: Cortical activation was altered differently in each cognitive sub-stage of motor imagery after

  8. Interaction matters: A perceived social partner alters the neural processing of human speech.

    Science.gov (United States)

    Rice, Katherine; Redcay, Elizabeth

    2016-04-01

    Mounting evidence suggests that social interaction changes how communicative behaviors (e.g., spoken language, gaze) are processed, but the precise neural bases by which social-interactive context may alter communication remain unknown. Various perspectives suggest that live interactions are more rewarding, more attention-grabbing, or require increased mentalizing-thinking about the thoughts of others. Dissociating between these possibilities is difficult because most extant neuroimaging paradigms examining social interaction have not directly compared live paradigms to conventional "offline" (or recorded) paradigms. We developed a novel fMRI paradigm to assess whether and how an interactive context changes the processing of speech matched in content and vocal characteristics. Participants listened to short vignettes--which contained no reference to people or mental states--believing that some vignettes were prerecorded and that others were presented over a real-time audio-feed by a live social partner. In actuality, all speech was prerecorded. Simply believing that speech was live increased activation in each participant's own mentalizing regions, defined using a functional localizer. Contrasting live to recorded speech did not reveal significant differences in attention or reward regions. Further, higher levels of autistic-like traits were associated with altered neural specialization for live interaction. These results suggest that humans engage in ongoing mentalizing about social partners, even when such mentalizing is not explicitly required, illustrating how social context shapes social cognition. Understanding communication in social context has important implications for typical and atypical social processing, especially for disorders like autism where social difficulties are more acute in live interaction. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Alterations in affective processing of attack images following September 11, 2001.

    Science.gov (United States)

    Tso, Ivy F; Chiu, Pearl H; King-Casas, Brooks R; Deldin, Patricia J

    2011-10-01

    The events of September 11, 2001 created unprecedented uncertainty about safety in the United States and created an aftermath with significant psychological impact across the world. This study examined emotional information encoding in 31 healthy individuals whose stress response symptoms ranged from none to a moderate level shortly after the attacks as assessed by the Impact of Event Scale-Revised. Participants viewed attack-related, negative (but attack-irrelevant), and neutral images while their event-related brain potentials (ERPs) were recorded. Attack images elicited enhanced P300 relative to negative and neutral images, and emotional images prompted larger slow waves than neutral images did. Total symptoms were correlated with altered N2, P300, and slow wave responses during valence processing. Specifically, hyperarousal and intrusion symptoms were associated with diminished stimulus discrimination between neutral and unpleasant images; avoidance symptoms were associated with hypervigilance, as suggested by reduced P300 difference between attack and other images and reduced appraisal of attack images as indicated by attenuated slow wave. The findings in this minimally symptomatic sample are compatible with the alterations in cognition in the posttraumatic stress disorder (PTSD) literature and are consistent with a dimensional model of PTSD. Copyright © 2011 International Society for Traumatic Stress Studies.

  10. Picturing survival memories: enhanced memory after fitness-relevant processing occurs for verbal and visual stimuli.

    Science.gov (United States)

    Otgaar, Henry; Smeets, Tom; van Bergen, Saskia

    2010-01-01

    Recent studies have shown that processing words according to a survival scenario leads to superior retention relative to control conditions. Here, we examined whether a survival recall advantage could be elicited by using pictures. Furthermore, in Experiment 1, we were interested in whether survival processing also results in improved memory for details. Undergraduates rated the relevance of pictures in a survival, moving, or pleasantness scenario and were subsequently given a surprise free recall test. We found that survival processing yielded superior retention. We also found that distortions occurred more often in the survival condition than in the pleasantness condition. In Experiment 2, we directly compared the survival recall effect between pictures and words. A comparable survival recall advantage was found for pictures and words. The present findings support the idea that memory is enhanced by processing information in terms of fitness value, yet at the same time, the present results suggest that this may increase the risk for memory distortions.

  11. Remote Sensing Analysis of Mineralized Alteration in the Ramand Area (Qazvin Province

    Directory of Open Access Journals (Sweden)

    Seyed Abolfazl Ezzati

    2016-07-01

    Full Text Available Introduction The Ramand area, southwest of Buin- Zahra, about 60 kilometers from Qazvin, lies in the igneous belt of the Urmieh-Dokhtar region, the main structural zone of north-central Iran. Rhyodacite and rhyolite lava flows are the principal host rocks of mineralization and alteration of the area, most of which occurs in faulted and brecciated zones alongmaj or northwest-trending fault systems (such as Kour-Cheshmeh, Hassan Abad and their branches. Clay minerals determined from satellite images indicated principally argillic hydrothermal alteration before laboratory mineralogical analysis. According to instrumental analyses, mineralized alteration with greater amounts of argillic halos and lesser amounts of sericitic-propylitic minerals contains quartz veinlets in the vertical and lateral sections. Initially, alteration in the Ramand area was revealed in ETM images by using the SPCA technique of Crosta and Moore, 1990 (Selective Principle Component Analysis. Compared with other techniques, SPCA results have reliable spectral signatures for identifying argillic minerals and Fe-oxides as the main mineralogical association in hydrothermal environments. Subsequently, multispectral images (ASTER were analyzed using band ratios.The results indicated silicification alteration along the faulted regions in the Ramand area. Later, areas of silicification alteration were prospected for precious and base metal mineralization.Sampling results suggested that the altered areas have some potential for epithermal mineralization, according to instrumental analyses and micrographic evidence. Materials and methods 1- Collecting satellite images, geological evidence and related documents 2- Image processing to reveal and identify the mineralized alteration. 3- Sampling of the mineralized zones indicated by the remote sensing. 4- Thin- and polished section microscopic studies. 5- X-ray diffraction analysis (XRD (19 samples, inductively coupled plasma mass

  12. Crystallization process of zircon and fergusonite during hydrothermal alteration in Nechalacho REE deposit, Thor Lake, Canada

    Science.gov (United States)

    Hoshino, M.; Watanabe, Y.; Murakami, H.; Kon, Y.; Tsunematsu, M.

    2012-04-01

    The core samples of two drill holes, which penetrate sub-horizontal mineralized horizons at Nechalacho REE deposit in the Proterozoic Thor Lake syenite, Canada, were studied in order to clarify magmatic and hydrothermal processes that enriched HFSE (e.g. Zr, Nb, Y and REE). Zircon is the most common REE minerals in Nechalacho REE deposit. The zircon is divided into five types as follows: Type-1 zircon occurs as single grain in phlogopite and the chondrite-normalized REE pattern is characterized by a steeply-rising slope from the LREE to the HREE with a positive Ce-anomaly and negative Eu-anomaly. This chemical characteristic is similar to that of igneous zircon. Type-2 zircon consists of HREE-rich magmatic porous core and LREE-Nb-F-rich hydrothermal rim. This type zircon is mostly included in phlogopite and fluorite, and occasionally in microcline. Type-3 zircon is characterized by euhedral to anhedral crystal, occurring in a complex intergrowth with REE fluorocarbonates. Type-3 zircons have high contents of REE, Nb and fluorine. Type-4 zircon consists of porous-core and -rim zones, but their chemical compositions are similar to each other. This type zircon is a subhedral crystal rimmed by fergusonite. Type-5 zircon is characterized by smaller, porous and subhedral to anhedral crystals. The interstices between small zircons are filled by fergusonite. Type-4 and -5 zircons show low REE and Nb contents. Occurrences of these five types of zircon are different according to the depth and degree of the alteration by hydrothermal solutions rich in F- and CO3 of the two drill holes, which permit a model for evolution of the zircon crystallization in Nechalacho REE deposit as follows: (1) type-1 (single magmatic zircon) is formed in miaskitic syenite. (2) LREE-Nb-F-rich hydrothermal zircon formed around HREE-rich magmatic zircon (type-2 zircon); (3) type-3 zircon crystallized thorough F and CO3-rich hydrothermal alteration of type-2 zircon which formed the complex

  13. Alteration of Lunar Rock Surfaces through Interaction with the Space Environment

    Science.gov (United States)

    Frushour, A. M.; Noble, S. K; Christoffersen, R.; Keller, L P.

    2014-01-01

    Space weathering occurs on all ex-posed surfaces of lunar rocks, as well as on the surfaces of smaller grains in the lunar regolith. Space weather-ing alters these exposed surfaces primarily through the action of solar wind ions and micrometeorite impact processes. On lunar rocks specifically, the alteration products produced by space weathering form surface coatings known as patina. Patinas can have spectral reflectance properties different than the underlying rock. An understanding of patina composition and thickness is therefore important for interpreting re-motely sensed data from airless solar system bodies. The purpose of this study is to try to understand the physical and chemical properties of patina by expanding the number of patinas known and characterized in the lunar rock sample collection.

  14. Buccal alterations in diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Negrato Carlos

    2010-01-01

    Full Text Available Abstract Long standing hyperglycaemia besides damaging the kidneys, eyes, nerves, blood vessels, heart, can also impair the function of the salivary glands leading to a reduction in the salivary flow. When salivary flow decreases, as a consequence of an acute hyperglycaemia, many buccal or oral alterations can occur such as: a increased concentration of mucin and glucose; b impaired production and/or action of many antimicrobial factors; c absence of a metalloprotein called gustin, that contains zinc and is responsible for the constant maturation of taste papillae; d bad taste; e oral candidiasis f increased cells exfoliation after contact, because of poor lubrication; g increased proliferation of pathogenic microorganisms; h coated tongue; i halitosis; and many others may occur as a consequence of chronic hyperglycaemia: a tongue alterations, generally a burning mouth; b periodontal disease; c white spots due to demineralization in the teeth; d caries; e delayed healing of wounds; f greater tendency to infections; g lichen planus; h mucosa ulcerations. Buccal alterations found in diabetic patients, although not specific of this disease, have its incidence and progression increased when an inadequate glycaemic control is present.

  15. Buccal alterations in diabetes mellitus.

    Science.gov (United States)

    Negrato, Carlos Antonio; Tarzia, Olinda

    2010-01-15

    Long standing hyperglycaemia besides damaging the kidneys, eyes, nerves, blood vessels, heart, can also impair the function of the salivary glands leading to a reduction in the salivary flow. When salivary flow decreases, as a consequence of an acute hyperglycaemia, many buccal or oral alterations can occur such as: a) increased concentration of mucin and glucose; b) impaired production and/or action of many antimicrobial factors; c) absence of a metalloprotein called gustin, that contains zinc and is responsible for the constant maturation of taste papillae; d) bad taste; e) oral candidiasis f) increased cells exfoliation after contact, because of poor lubrication; g) increased proliferation of pathogenic microorganisms; h) coated tongue; i) halitosis; and many others may occur as a consequence of chronic hyperglycaemia: a) tongue alterations, generally a burning mouth; b) periodontal disease; c) white spots due to demineralization in the teeth; d) caries; e) delayed healing of wounds; f) greater tendency to infections; g) lichen planus; h) mucosa ulcerations. Buccal alterations found in diabetic patients, although not specific of this disease, have its incidence and progression increased when an inadequate glycaemic control is present.

  16. Network analysis of genomic alteration profiles reveals co-altered functional modules and driver genes for glioblastoma.

    Science.gov (United States)

    Gu, Yunyan; Wang, Hongwei; Qin, Yao; Zhang, Yujing; Zhao, Wenyuan; Qi, Lishuang; Zhang, Yuannv; Wang, Chenguang; Guo, Zheng

    2013-03-01

    The heterogeneity of genetic alterations in human cancer genomes presents a major challenge to advancing our understanding of cancer mechanisms and identifying cancer driver genes. To tackle this heterogeneity problem, many approaches have been proposed to investigate genetic alterations and predict driver genes at the individual pathway level. However, most of these approaches ignore the correlation of alteration events between pathways and miss many genes with rare alterations collectively contributing to carcinogenesis. Here, we devise a network-based approach to capture the cooperative functional modules hidden in genome-wide somatic mutation and copy number alteration profiles of glioblastoma (GBM) from The Cancer Genome Atlas (TCGA), where a module is a set of altered genes with dense interactions in the protein interaction network. We identify 7 pairs of significantly co-altered modules that involve the main pathways known to be altered in GBM (TP53, RB and RTK signaling pathways) and highlight the striking co-occurring alterations among these GBM pathways. By taking into account the non-random correlation of gene alterations, the property of co-alteration could distinguish oncogenic modules that contain driver genes involved in the progression of GBM. The collaboration among cancer pathways suggests that the redundant models and aggravating models could shed new light on the potential mechanisms during carcinogenesis and provide new indications for the design of cancer therapeutic strategies.

  17. Mineralogy and Textural Characteristics of Fine-grained Rims in the Yamato 791198 CM2 Carbonaceous Chondrite: Constraints on the Location of Aqueous Alteration

    Science.gov (United States)

    Chizmadia, Lysa J.; Brearley, Adrian J.

    2003-01-01

    Carbonaceous chondrites provide important clues into the nature of physical and chemical processes in the early solar system. A question of key importance concerns the role of water in solar nebular and asteroidal processes. The effects of water on primary mineral assemblages have been widely recognized in chondritic meteorites, especially the CI and CM carbonaceous chondrites. These meteorites have undergone extensive aqueous alteration that occurred prior to their arrival on Earth. In the case of the CM chondrites, this alteration has resulted in the partial to complete replacement of the primary nebular phases with secondary alteration phases. Considerable controversy exists as to the exact location where the alteration of the CM chondrites occurred. Several textural lines of evidence have been cited in support of aqueous alteration prior to the accretion of the final parent asteroid. An important line of evidence to support this hypothesis is the dis-equilibrium nature of fine-grained rims and matrix materials. [2] also noted the juxtaposition of micron-sized Fe-Ni metal grains and apparently unaltered chondrule glass against hydrated rim silicates. Conversely, there is a large body of evidence in favor of parent body alteration such as the occurrence of undisturbed Fe-rich aureoles and the systematic redistribution of elemental components over millimeters, e.g., Mg(+2) into the matrix and Fe(+2) into chondrules etc.

  18. Sleep Deprivation Alters Choice Strategy Without Altering Uncertainty or Loss Aversion Preferences

    Directory of Open Access Journals (Sweden)

    O'Dhaniel A Mullette-Gillman

    2015-10-01

    Full Text Available Sleep deprivation alters decision making; however, it is unclear what specific cognitive processes are modified to drive altered choices. In this manuscript, we examined how one night of total sleep deprivation (TSD alters economic decision making. We specifically examined changes in uncertainty preferences dissociably from changes in the strategy with which participants engage with presented choice information. With high test-retest reliability, we show that TSD does not alter uncertainty preferences or loss aversion. Rather, TSD alters the information the participants rely upon to make their choices. Utilizing a choice strategy metric which contrasts the influence of maximizing and satisficing information on choice behavior, we find that TSD alters the relative reliance on maximizing information and satisficing information, in the gains domain. This alteration is the result of participants both decreasing their reliance on cognitively-complex maximizing information and a concomitant increase in the use of readily-available satisficing information. TSD did not result in a decrease in overall information use in either domain. These results show that sleep deprivation alters decision making by altering the informational strategies that participants employ, without altering their preferences.

  19. Sleep deprivation alters choice strategy without altering uncertainty or loss aversion preferences.

    Science.gov (United States)

    Mullette-Gillman, O'Dhaniel A; Kurnianingsih, Yoanna A; Liu, Jean C J

    2015-01-01

    Sleep deprivation alters decision making; however, it is unclear what specific cognitive processes are modified to drive altered choices. In this manuscript, we examined how one night of total sleep deprivation (TSD) alters economic decision making. We specifically examined changes in uncertainty preferences dissociably from changes in the strategy with which participants engage with presented choice information. With high test-retest reliability, we show that TSD does not alter uncertainty preferences or loss aversion. Rather, TSD alters the information the participants rely upon to make their choices. Utilizing a choice strategy metric which contrasts the influence of maximizing and satisficing information on choice behavior, we find that TSD alters the relative reliance on maximizing information and satisficing information, in the gains domain. This alteration is the result of participants both decreasing their reliance on cognitively-complex maximizing information and a concomitant increase in the use of readily-available satisficing information. TSD did not result in a decrease in overall information use in either domain. These results show that sleep deprivation alters decision making by altering the informational strategies that participants employ, without altering their preferences.

  20. Induction and reversion process of molecular and cytological alterations after highly irradiated food ingestion in mice

    International Nuclear Information System (INIS)

    Rojo M, M.I.; Fernandez C, M.

    1984-01-01

    The molecular and cytological alterations induced in a mammal (Mus musculus) fed ad libitum with a balanced pellet diet irradiated with 50 KGy gamma radiation from weaning, for different periods, are analyzed. The transient chromosomal changes that recall tumor-like phenomena could be the expression of the damage and repair processes induced by changed molecules present in irradiated food. The reversible alterations of DNA structure and cytoplasmatic soluble proteins observed in mice fed with irradiated pellet diet could be interpreted as a result of the enhancement of the repair processes which could also explain the significant increase of the radioresistance of DNA found at 200 days after irradiated food ingestion. Finally, our results would suggest an induction of a pseudo-neoplasia due to a prolongated and exclusive ingestion of food irradiated with sterilizing gamma dose. Moreover, the maintenance of the irradiated diet induce the reversion of the observed phenomena by an eventual activation of the repair mechanisms. (Author)

  1. RESEARCH CONCERNING INSTALATION OF ALTERATIVE PROCESSES IN COW AND BUFFALO BUTTER DURING FREEZING STORAGE

    OpenAIRE

    Andreea Lup Dragomir; Flavia Pop

    2009-01-01

    Physicochemical characteristics and freshness indicators of cow and buffalo butter during freezing (-15 ... -18oC) storage were studied. Changes in freshness parameters and alterative processes installation, when butter becomes improperly for consumption were studied, inducing acidity, peroxide value (PV), iodine value (IV) andthe presence of epyhidrinic aldehyde. There was an increase of titrable acidity during storage, cow butter hydrolysis was installed after 35 days and after 30 days for ...

  2. Toxic Knowledge: Self-Alteration Through Child Abuse Work.

    Science.gov (United States)

    Sigad, Laura I; Davidov, Jonathan; Lev-Wiesel, Rachel; Eisikovits, Zvi

    2016-02-01

    The purpose of the present article is to examine the multiple ways in which the private lives of professionals are affected by involvement with child abuse intervention and prevention. Using a descriptive-phenomenological perspective and 40 in-depth interviews with professionals to present a model based on qualitative data, we studied the ways in which child abuse professionals conceptualize, understand, and integrate their experiences into their personal and family lives. We find that the process of internalizing child abuse knowledge occurs in two domains: One affirms or denies the existence of the phenomenon; the other concerns the strategies used to contend with the effects of working in abuse. Knowledge of child abuse is toxic, in the sense that it serves as a catalyst leading to the alteration of one's self-perception and parental identity. We present a typology of self-alteration resulting from child abuse knowledge and describe the mechanism of this change. © The Author(s) 2014.

  3. Modulation of ROS levels in fibroblasts by altering mitochondria regulates the process of wound healing.

    Science.gov (United States)

    Janda, Jaroslav; Nfonsam, Valentine; Calienes, Fernanda; Sligh, James E; Jandova, Jana

    2016-05-01

    Mitochondria are the major source of reactive oxygen species (ROS) in fibroblasts which are thought to be crucial regulators of wound healing with a potential to affect the expression of nuclear genes involved in this process. ROS generated by mitochondria are involved in all stages of tissue repair process but the regulation of ROS-generating system in fibroblasts still remains poorly understood. The purpose of this study was to better understand molecular mechanisms of how the regulation of ROS levels generated by mitochondria may influence the process of wound repair. Cybrid model system of mtDNA variations was used to study the functional consequences of altered ROS levels on wound healing responses in a uniform nuclear background of cultured ρ(0) fibroblasts. Mitochondrial ROS in cybrids were modulated by antioxidants that quench ROS to examine their ability to close the wound. Real-time PCR arrays were used to investigate whether ROS generated by specific mtDNA variants have the ability to alter expression of some key nuclear-encoded genes central to the wound healing response and oxidative stress. Our data suggest levels of mitochondrial ROS affect expression of some nuclear encoded genes central to wound healing response and oxidative stress and modulation of mitochondrial ROS by antioxidants positively affects in vitro process of wound closure. Thus, regulation of mitochondrial ROS-generating system in fibroblasts can be used as effective natural redox-based strategy to help treat non-healing wounds.

  4. Altered neural processing of reward and punishment in adolescents with Major Depressive Disorder.

    Science.gov (United States)

    Landes, I; Bakos, S; Kohls, G; Bartling, J; Schulte-Körne, G; Greimel, E

    2018-05-01

    Altered reward and punishment function has been suggested as an important vulnerability factor for the development of Major Depressive Disorder (MDD). Prior ERP studies found evidence for neurophysiological dysfunctions in reinforcement processes in adults with MDD. To date, only few ERP studies have examined the neural underpinnings of reinforcement processing in adolescents diagnosed with MDD. The present event-related potential (ERP) study aimed to investigate neurophysiological mechanisms of anticipation and consumption of reward and punishment in adolescents with MDD in one comprehensive paradigm. During ERP recording, 25 adolescents with MDD and 29 healthy controls (12-17 years) completed a Monetary Incentive Delay Task comprising both a monetary reward and a monetary punishment condition. During anticipation, the cue-P3 signaling attentional allocation was recorded. During consumption, the feedback-P3 and Reward Positivity (RewP) were recorded to capture attentional allocation and outcome evaluation, respectively. Compared to controls, adolescents with MDD showed prolonged cue-P3 latencies to reward cues. Furthermore, unlike controls, adolescents with MDD displayed shorter feedback-P3 latencies in the reward versus punishment condition. RewPs did not differ between groups. It remains unanswered whether the observed alterations in adolescent MDD represent a state or trait. Delayed neural processing of reward cues corresponds to the clinical presentation of adolescent MDD with reduced motivational tendencies to obtain rewards. Relatively shorter feedback-P3 latencies in the reward versus punishment condition could indicate a high salience of performance-contingent reward. Frequent exposure of negatively biased adolescents with MDD to performance-contingent rewards might constitute a promising intervention approach. Copyright © 2018 Elsevier B.V. All rights reserved.

  5. Mineralogical and structural transformations related to alterations in hydrothermal and climatological conditions of basic vulcanic rocks from northern Parana (Ribeirao Preto region, SP, Brazil)

    International Nuclear Information System (INIS)

    Goncalves, N.M.M.

    1987-01-01

    Detailed studies of the basic vulcanic rocks of northern Parana basin (Region of Ribeirao Preto, SP) reveled that these rocks were affected by pre-meteoric activity (hydrothermal alteration) before being exposed to the supergene system of alteration linked to the lithosphere/atmosphere interface. Mineralogical and structural transformation are studied. The appearance of sequential crystalline-chemical paragenesis in zones suggest that the hydrothermal activity occurred during two successives processes of alteration: the expulsion of the water from the rock during the later stages of magma cooling and the continous process of dissolution of the rock wall and the ionic diffusion involving the rock sistem of structural voids. The hydro-thermal action was followed by weathering action developing a thin 'front' of superficial alteration. This alteration system, can lead to the formation of three major levels of alteration horizons and superficial accumulations: alterites, glebular and suil surface materials. (C.D.G.) [pt

  6. The Formation of Chimeric Nanomorphologies, as a Reflection of Naturally Occurring Thermodynamic Processes

    Science.gov (United States)

    Naziris, N.; Demetzos, C.

    2017-11-01

    The self-assembly process of different in nature biomaterials leads to the morphogenesis of various nano-structures, where the individual molecule properties (e.g. hydrophilic-to-hydrophobic balance and elasticity), profoundly affect the intermediate surfaces’ interfacial thermodynamics. Herein, the mixing of a phospholipid and an amphiphilic block copolymer, through the thin-film hydration method, gave different morphologies, among which there were vesicles (i.e. liposomes and polymersomes), micelles and worm-like structures. The formation of such variety of structures is attributed to divergent entropic pathways, which are determined by a number of parameters, such as the lipid:polymer molar ratio and the polymer composition. The developed nanosystems are considered as chimeric/mixed, because of the two different in type biomaterials that compose them. The vesicles also exhibited membrane “irregularities”, which are connected with their biophysical behavior. Nature has “chosen” vesicular forms to be the thermodynamically stable “biological apartments”, in which life was enclosed and additionally, vesicles provided compartmentalized systems, where the intracellular environment was built. Phospholipid properties result in membranes/bilayers that harmonically assimilate other molecules, like proteins and retain their integrity and functionality, while gaining additional features. A cause that alters this relationship might induce changes in the membrane composition and morphology, with respect to lipid rafts/domains, what has been linked with the activation and development of certain human disorders/diseases. The self-assembly of two different biomaterials into various structures that present distinct membrane phenomena is believed to simulate these natural processes.

  7. Alteration of properties of rock during their selection by shooting core lifter

    Energy Technology Data Exchange (ETDEWEB)

    Malinin, V F

    1969-01-01

    During the process of intrusion of the core lifter into rock, splitting and dislocation of the granules and crystals which compose it occur. In the core lifters, single small nondisintegrated fragments are sometimes encountered. Data on comparison of porosity of crushed cores and rock from which they were selected indicate increase in porosity and penetration of the filtrate of the drilling solution during the process of coring. The determined residual oil saturation of the core is different from the residual oil saturation of the rock from which they were selected. The permeability of cores of rock with high porosity is altered.

  8. Neuroimaging meta-analysis of cannabis use studies reveals convergent functional alterations in brain regions supporting cognitive control and reward processing.

    Science.gov (United States)

    Yanes, Julio A; Riedel, Michael C; Ray, Kimberly L; Kirkland, Anna E; Bird, Ryan T; Boeving, Emily R; Reid, Meredith A; Gonzalez, Raul; Robinson, Jennifer L; Laird, Angela R; Sutherland, Matthew T

    2018-03-01

    Lagging behind rapid changes to state laws, societal views, and medical practice is the scientific investigation of cannabis's impact on the human brain. While several brain imaging studies have contributed important insight into neurobiological alterations linked with cannabis use, our understanding remains limited. Here, we sought to delineate those brain regions that consistently demonstrate functional alterations among cannabis users versus non-users across neuroimaging studies using the activation likelihood estimation meta-analysis framework. In ancillary analyses, we characterized task-related brain networks that co-activate with cannabis-affected regions using data archived in a large neuroimaging repository, and then determined which psychological processes may be disrupted via functional decoding techniques. When considering convergent alterations among users, decreased activation was observed in the anterior cingulate cortex, which co-activated with frontal, parietal, and limbic areas and was linked with cognitive control processes. Similarly, decreased activation was observed in the dorsolateral prefrontal cortex, which co-activated with frontal and occipital areas and linked with attention-related processes. Conversely, increased activation among users was observed in the striatum, which co-activated with frontal, parietal, and other limbic areas and linked with reward processing. These meta-analytic outcomes indicate that cannabis use is linked with differential, region-specific effects across the brain.

  9. Human ecstasy (MDMA) polydrug users have altered brain activation during semantic processing.

    Science.gov (United States)

    Watkins, Tristan J; Raj, Vidya; Lee, Junghee; Dietrich, Mary S; Cao, Aize; Blackford, Jennifer U; Salomon, Ronald M; Park, Sohee; Benningfield, Margaret M; Di Iorio, Christina R; Cowan, Ronald L

    2013-05-01

    Ecstasy (3,4-methylenedioxymethamphetamine [MDMA]) polydrug users have verbal memory performance that is statistically significantly lower than that of control subjects. Studies have correlated long-term MDMA use with altered brain activation in regions that play a role in verbal memory. The aim of our study was to examine the association of lifetime ecstasy use with semantic memory performance and brain activation in ecstasy polydrug users. A total of 23 abstinent ecstasy polydrug users (age = 24.57 years) and 11 controls (age = 22.36 years) performed a two-part functional magnetic resonance imaging (fMRI) semantic encoding and recognition task. To isolate brain regions activated during each semantic task, we created statistical activation maps in which brain activation was greater for word stimuli than for non-word stimuli (corrected p ecstasy polydrug users had greater activation during semantic encoding bilaterally in language processing regions, including Brodmann areas 7, 39, and 40. Of this bilateral activation, signal intensity with a peak T in the right superior parietal lobe was correlated with lifetime ecstasy use (r s = 0.43, p = 0.042). Behavioral performance did not differ between groups. These findings demonstrate that ecstasy polydrug users have increased brain activation during semantic processing. This increase in brain activation in the absence of behavioral deficits suggests that ecstasy polydrug users have reduced cortical efficiency during semantic encoding, possibly secondary to MDMA-induced 5-HT neurotoxicity. Although pre-existing differences cannot be ruled out, this suggests the possibility of a compensatory mechanism allowing ecstasy polydrug users to perform equivalently to controls, providing additional support for an association of altered cerebral neurophysiology with MDMA exposure.

  10. Physiological alterations in UV-irradiated cells: liquid holding recovery

    International Nuclear Information System (INIS)

    Aragao, B.R.

    1980-01-01

    The biochemical and physiological alterations that occur in ultraviolet irradiated cells, during liquid holding have been studied. Incubation in buffer acts not to interfer directly with the mechanic repairs but by promoting metabolic alterations that would block some irreversible and lethal physiological responses. (L.M.J.) [pt

  11. The alteration of intracellular enzymes. III. The effect of temperature on the kinetics of altered and unaltered yeast catalase.

    Science.gov (United States)

    FRASER, M J; KAPLAN, J G

    1955-03-20

    the case of catalase, of desorbing the enzyme from the interface into its rolled-up, soluble, highly specific configuration. While the interfacial hypothesis has successfully withstood this experimental attack, the present data do not provide its unequivocal proof, since they are consistent with any hypothesis of alteration in which the unaltered, intracellular enzyme is in a relatively disordered state by comparison to the altered enzyme. While evidence of an interfacial process in enzyme alteration has been adduced previously, critical proof of the interfacial hypothesis awaits creation of a model system, in which most of the aspects of intracellular alteration can be reproduced. 6. Certain of the changes in kinetic properties following alteration of the intracellular enzyme, such as increased activity and the modified energies and entropies of activation of both enzyme-substrate system and heat destruction of the catalase itself, might be explained by a decrease (two orders of magnitude) in the effective hydrogen ion concentration, allowing the intracellular enzyme to be brought to the same pH as the extracellular medium. If such a pH change does, in fact, occur, it is necessary to invoke the interfacial hypothesis to explain why the unaltered, intracellular enzyme is in equilibrium with a medium whose pH is approximately 2 units lower than that of the cytoplasm itself. 7. It is concluded that kinetic data of this kind may be used to shed light on the structure of a soluble, cytoplasmic enzyme, not attached to any of the formed elements within the cell, yet organized within it in a condition of relatively low structural specificity; further, that information obtained exclusively from a study of the kinetics of the extracted or crystalline enzymes may not, in the case of this enzyme, at least, be extrapolated to the same enzyme within the intact cell.

  12. Timescales and settings for alteration of chondritic meteorites

    Energy Technology Data Exchange (ETDEWEB)

    Krot, A N; Hutcheon, I D; Brearley, A J; Pravdivtseva, O V; Petaev, M I; Hohenberg, C M

    2005-11-16

    Most groups of chondritic meteorites experienced diverse styles of secondary alteration to various degrees that resulted in formation of hydrous and anhydrous minerals (e.g., phyllosilicates, magnetite, carbonates, ferrous olivine, hedenbergite, wollastonite, grossular, andradite, nepheline, sodalite, Fe,Ni-carbides, pentlandite, pyrrhotite, Ni-rich metal). Mineralogical, petrographic, and isotopic observations suggest that the alteration occurred in the presence of aqueous solutions under variable conditions (temperature, water/rock ratio, redox conditions, and fluid compositions) in an asteroidal setting, and, in many cases, was multistage. Although some alteration predated agglomeration of the final chondrite asteroidal bodies (i.e. was pre-accretionary), it seems highly unlikely that the alteration occurred in the solar nebula, nor in planetesimals of earlier generations. Short-lived isotope chronologies ({sup 26}Al-{sup 26}Mg, {sup 53}Mn-{sup 53}Cr, {sup 129}I-{sup 129}Xe) of the secondary minerals indicate that the alteration started within 1-2 Ma after formation of the Ca,Al-rich inclusions and lasted up to 15 Ma. These observations suggest that chondrite parent bodies must have accreted within the first 1-2 Ma after collapse of the protosolar molecular cloud and provide strong evidence for an early onset of aqueous activity on these bodies.

  13. Altered organization of face processing networks in temporal lobe epilepsy

    Science.gov (United States)

    Riley, Jeffrey D.; Fling, Brett W.; Cramer, Steven C.; Lin, Jack J.

    2015-01-01

    SUMMARY Objective Deficits in social cognition are common and significant in people with temporal lobe epilepsy (TLE), but the functional and structural underpinnings remain unclear. The present study investigated how the side of seizure focus impacts face processing networks in temporal lobe epilepsy. Methods We used functional magnetic resonance imaging (fMRI) of a face processing paradigm to identify face responsive regions in 24 individuals with unilateral temporal lobe epilepsy (Left = 15; Right = 9) and 19 healthy controls. fMRI signals of face responsive regions ispilateral and contralateral to the side of seizure onset were delineated in TLE and compared to the healthy controls with right and left side combined. Diffusion tensor images were acquired to investigate structural connectivity between face regions that differed in fMRI signals between the two groups. Results In temporal lobe epilepsy, activation of the cortical face processing networks varied according to side of seizure onset. In temporal lobe epilepsy, the laterality of amygdala activation was shifted to the side contralateral to the seizure focus while controls showed no significant asymmetry. Furthermore, compared to controls, patients with TLE showed decreased activation of the occipital face responsive region in the ipsilateral side and an increased activity of the anterior temporal lobe in the contralateral side to the seizure focus. Probabilistic tractography revealed that the occipital face area and anterior temporal lobe are connected via the inferior longitudinal fasciculus, which in individuals with temporal lobe epilepsy showed reduced integrity. Significance Taken together, these findings suggest that brain function and white matter integrity of networks subserving face processing are impaired on the side of seizure onset, accompanied by altered responses on the side contralateral to the seizure. PMID:25823855

  14. Aqueous corrosion of borosilicate glasses. Nature and properties of alteration layers

    International Nuclear Information System (INIS)

    Trotignon, Laurent

    1990-01-01

    This research thesis addresses physical and chemical processes which occur during aqueous corrosion of silicates, and the study of the properties of their interfaces with solutions, and thus issues related to the fate of high activity nuclear wastes which are embedded in a vitreous matrix as the potential release of radionuclides towards the environment then depends on the glass parcel behaviour submitted to chemical attacks which could alter it, notably by aqueous corrosion. The objective is then to model the dissolution of nuclear glass over long periods of time, and to predict the behaviour of radionuclides. The author compared the corrosion and alteration layers of gradually more complex borosilicate glasses, from a ternary sodium borosilicate glass to a simulated nuclear glass (the French reference glass R7T7). Complexity is increased by adding oxides. After some theoretical recalls on the structure and corrosion of borosilicate glasses, the author presents the studied materials, the corrosion experiments, and analytical techniques used to study alteration layers. The mechanism of formation of altered layers is studied based on corrosion experiments performed at 90 C on the whole set of glasses. Alteration layers formed on corroded glasses are studied and compared by using various techniques: electronic microscopy, high energy ion beams, spectroscopy, infrared, photo-electron spectroscopy. Implications for underground storage of nuclear glasses are discussed

  15. THE TRANSFORMATIONAL PROCESSES INVOLVING MOTOR SKILLS THAT OCCUR UNDER THE INFLUENCE OF BASIC PRELIMINARY TRAINING IN YOUNG HANDBALL PLAYERS

    Directory of Open Access Journals (Sweden)

    Markovic Sasa

    2011-06-01

    Full Text Available The population from which we extracted a sample of 76 subjects consisted of elementary school students in Kursumlija, all male, aged 12-13, who were divided into a sub-sample consisting of 38 young handball players who took part in the training sessions of a school of handball and another sub-sample consisting of 38 non-athletes, who only took part in their regular physical education classes. The aim of the research was to determine the transformation processes involving motor skills, which occur under the influence of basic preliminary training in young handball players. The subject matter of the study was to examine whether a statistically significant increase in the level of motor skills would occur under the influence of physical exercise as part of basic preliminary training in the final as compared to the initial state. Six motor tests which define the dimensions of explosive and repetitive strength were used. The results of the research indicate that significant transformational processes involving the motor skills of young handball players occurred in the final as compared to the initial measuring, under the influence of basic preliminary training.

  16. Prion replication occurs in endogenous adult neural stem cells and alters their neuronal fate: involvement of endogenous neural stem cells in prion diseases.

    Directory of Open Access Journals (Sweden)

    Aroa Relaño-Ginès

    Full Text Available Prion diseases are irreversible progressive neurodegenerative diseases, leading to severe incapacity and death. They are characterized in the brain by prion amyloid deposits, vacuolisation, astrocytosis, neuronal degeneration, and by cognitive, behavioural and physical impairments. There is no treatment for these disorders and stem cell therapy therefore represents an interesting new approach. Gains could not only result from the cell transplantation, but also from the stimulation of endogenous neural stem cells (NSC or by the combination of both approaches. However, the development of such strategies requires a detailed knowledge of the pathology, particularly concerning the status of the adult neurogenesis and endogenous NSC during the development of the disease. During the past decade, several studies have consistently shown that NSC reside in the adult mammalian central nervous system (CNS and that adult neurogenesis occurs throughout the adulthood in the subventricular zone of the lateral ventricle or the Dentate Gyrus of the hippocampus. Adult NSC are believed to constitute a reservoir for neuronal replacement during normal cell turnover or after brain injury. However, the activation of this system does not fully compensate the neuronal loss that occurs during neurodegenerative diseases and could even contribute to the disease progression. We investigated here the status of these cells during the development of prion disorders. We were able to show that NSC accumulate and replicate prions. Importantly, this resulted in the alteration of their neuronal fate which then represents a new pathologic event that might underlie the rapid progression of the disease.

  17. Alterations in Resting-State Activity Relate to Performance in a Verbal Recognition Task

    Science.gov (United States)

    López Zunini, Rocío A.; Thivierge, Jean-Philippe; Kousaie, Shanna; Sheppard, Christine; Taler, Vanessa

    2013-01-01

    In the brain, resting-state activity refers to non-random patterns of intrinsic activity occurring when participants are not actively engaged in a task. We monitored resting-state activity using electroencephalogram (EEG) both before and after a verbal recognition task. We show a strong positive correlation between accuracy in verbal recognition and pre-task resting-state alpha power at posterior sites. We further characterized this effect by examining resting-state post-task activity. We found marked alterations in resting-state alpha power when comparing pre- and post-task periods, with more pronounced alterations in participants that attained higher task accuracy. These findings support a dynamical view of cognitive processes where patterns of ongoing brain activity can facilitate –or interfere– with optimal task performance. PMID:23785436

  18. Aqueous alteration of Japanese simulated waste glass P0798: Effects of alteration-phase formation on alteration rate and cesium retention

    International Nuclear Information System (INIS)

    Inagaki, Y.; Shinkai, A.; Idemistu, K.; Arima, T.; Yoshikawa, H.; Yui, M.

    2006-01-01

    Aqueous alteration tests were performed with a Japanese simulated waste glass P0798 in alkaline solutions as a function of pH or species/concentration of alkaline metals in the solution in order to evaluate the alteration conditions determining whether smectite (2:1 clay mineral) or analcime (zeolite) forms as the major alteration-phase. XRD analysis of the alteration-phases showed that smectite forms at any pH between 9.5 and 12, and analcime forms at pH above 11, though the formation also depends on species and concentrations of alkaline metals in the solution. These results cannot agree with the thermodynamically predicted phase stability, e.g., smectite is more stable than the thermodynamic prediction shows. On the basis of the results of alteration conditions, the alteration tests were performed under smectite forming conditions, where only smectite forms or no crystalline phases form, in order to evaluate the alteration rate and the mechanism of cesium release/retention. The results showed that the glass alteration proceeds slowly in proportion to square root of time under smectite forming conditions, which indicates that the alteration rate can be controlled by a diffusion process. It was suggested that the alteration rate under smectite forming conditions is independent of the pH, alkaline metal species/concentration in the solution and whether smectite actually forms or not. The results also indicated that most of cesium dissolved from the glass can be retained in the alteration-phases by reversible sorption onto smectite or irreversible incorporation into analcime, pollucite or solid solutions of them

  19. Can a Proper T-Cell Development Occur in an Altered Thymic Epithelium? Lessons From EphB-Deficient Thymi

    Directory of Open Access Journals (Sweden)

    Juan José Muñoz

    2018-04-01

    Full Text Available For a long time, the effects of distinct Eph tyrosine kinase receptors and their ligands, ephrins on the structure, immunophenotype, and development of thymus and their main cell components, thymocytes (T and thymic epithelial cells (TECs, have been studied. In recent years, the thymic phenotype of mutant mice deficient in several Ephs and ephrins B has been determined. Remarkably, thymic stroma in these animals exhibits important defects that appear early in ontogeny but little alterations in the proportions of distinct lymphoid cell populations. In the present manuscript, we summarize and extend these results discussing possible mechanisms governing phenotypical and functional thymocyte maturation in an absence of the critical T–TEC interactions, concluding that some signaling mediated by key molecules, such as MHCII, CD80, β5t, Aire, etc. could be sufficient to enable a proper maturation of thymocytes, independently of morphological alterations affecting thymic epithelium.

  20. An fMRI-study of locally oriented perception in autism: altered early visual processing of the block design test.

    Science.gov (United States)

    Bölte, S; Hubl, D; Dierks, T; Holtmann, M; Poustka, F

    2008-01-01

    Autism has been associated with enhanced local processing on visual tasks. Originally, this was based on findings that individuals with autism exhibited peak performance on the block design test (BDT) from the Wechsler Intelligence Scales. In autism, the neurofunctional correlates of local bias on this test have not yet been established, although there is evidence of alterations in the early visual cortex. Functional MRI was used to analyze hemodynamic responses in the striate and extrastriate visual cortex during BDT performance and a color counting control task in subjects with autism compared to healthy controls. In autism, BDT processing was accompanied by low blood oxygenation level-dependent signal changes in the right ventral quadrant of V2. Findings indicate that, in autism, locally oriented processing of the BDT is associated with altered responses of angle and grating-selective neurons, that contribute to shape representation, figure-ground, and gestalt organization. The findings favor a low-level explanation of BDT performance in autism.

  1. Altered neural reward and loss processing and prediction error signalling in depression

    Science.gov (United States)

    Ubl, Bettina; Kuehner, Christine; Kirsch, Peter; Ruttorf, Michaela

    2015-01-01

    Dysfunctional processing of reward and punishment may play an important role in depression. However, functional magnetic resonance imaging (fMRI) studies have shown heterogeneous results for reward processing in fronto-striatal regions. We examined neural responsivity associated with the processing of reward and loss during anticipation and receipt of incentives and related prediction error (PE) signalling in depressed individuals. Thirty medication-free depressed persons and 28 healthy controls performed an fMRI reward paradigm. Regions of interest analyses focused on neural responses during anticipation and receipt of gains and losses and related PE-signals. Additionally, we assessed the relationship between neural responsivity during gain/loss processing and hedonic capacity. When compared with healthy controls, depressed individuals showed reduced fronto-striatal activity during anticipation of gains and losses. The groups did not significantly differ in response to reward and loss outcomes. In depressed individuals, activity increases in the orbitofrontal cortex and nucleus accumbens during reward anticipation were associated with hedonic capacity. Depressed individuals showed an absence of reward-related PEs but encoded loss-related PEs in the ventral striatum. Depression seems to be linked to blunted responsivity in fronto-striatal regions associated with limited motivational responses for rewards and losses. Alterations in PE encoding might mirror blunted reward- and enhanced loss-related associative learning in depression. PMID:25567763

  2. Physical Alteration of Martian Dust Grains, Its Influence on Detection of Clays and Identification of Aqueous Processes on Mars

    Science.gov (United States)

    Bishop, Janice L.; Drief, Ahmed; Dyar, Darby

    2003-01-01

    Clays, if present on Mars, have been illusive. Determining whether or not clay minerals and other aqueous alteration species are present on Mars provides key information about the extent and duration of aqueous processes on Mars. The purpose of this study is to characterize in detail changes in the mineral grains resulting from grinding and to assess the influence of physical processes on clay minerals on the surface of Mars. Physical alteration through grinding was shown to greatly affect the structure and a number of properties of antigorite and kaolinite. This project builds on an initial study and includes a combination of SEM, HRTEM, reflectance and M ssbauer spectroscopies. Grain size was found to decrease, as expected, with grinding. In addition, nanophase carbonate, Si-OH and iron oxide species were formed.

  3. Learning Arm/Hand Coordination with an Altered Visual Input

    Directory of Open Access Journals (Sweden)

    Simona Denisia Iftime Nielsen

    2010-01-01

    Full Text Available The focus of this study was to test a novel tool for the analysis of motor coordination with an altered visual input. The altered visual input was created using special glasses that presented the view as recorded by a video camera placed at various positions around the subject. The camera was positioned at a frontal (F, lateral (L, or top (T position with respect to the subject. We studied the differences between the arm-end (wrist trajectories while grasping an object between altered vision (F, L, and T conditions and normal vision (N in ten subjects. The outcome measures from the analysis were the trajectory errors, the movement parameters, and the time of execution. We found substantial trajectory errors and an increased execution time at the baseline of the study. We also found that trajectory errors decreased in all conditions after three days of practice with the altered vision in the F condition only for 20 minutes per day, suggesting that recalibration of the visual systems occurred relatively quickly. These results indicate that this recalibration occurs via movement training in an altered condition. The results also suggest that recalibration is more difficult to achieve for altered vision in the F and L conditions compared to the T condition. This study has direct implications on the design of new rehabilitation systems.

  4. Altered Evoked Gamma-Band Responses Reveal Impaired Early Visual Processing in ADHD Children

    Science.gov (United States)

    Lenz, Daniel; Krauel, Kerstin; Flechtner, Hans-Henning; Schadow, Jeanette; Hinrichs, Hermann; Herrmann, Christoph S.

    2010-01-01

    Neurophysiological studies yield contrary results whether attentional problems of patients with attention-deficit/hyperactivity disorder (ADHD) are related to early visual processing deficits or not. Evoked gamma-band responses (GBRs), being among the first cortical responses occurring as early as 90 ms after visual stimulation in human EEG, have…

  5. The Scope of Our Affective Influences: When and How Naturally Occurring Positive, Negative, and Neutral Affects Alter Judgment.

    Science.gov (United States)

    Gasper, Karen; Danube, Cinnamon L

    2016-03-01

    To determine how naturally arising affect alters judgment, we examined whether (a) affective states exert a specific, rather than a general, influence on valenced-specific judgments; (b) neutral affect is associated with increased neutral judgments, independent of positive, negative, and ambivalent affects, and whether neutral judgments are associated with behavioral disengagement; and (c) the informational value of naturally arising states may be difficult to alter via salience and relevance manipulations. The results support several conclusions: (a) Affective states exerted a judgment-specific effect-positive affect was most strongly associated with positive judgments, negative affect with negative judgments, and neutral affect with neutral judgments. (b) Neutral affect influenced judgments, taking into account positive, negative, and ambivalent affects; and neutral judgments predicted behavioral disengagement. (c) With the exception of negative affect, naturally arising affective states typically influenced judgments regardless of their salience and relevance. © 2016 by the Society for Personality and Social Psychology, Inc.

  6. Naturally occurring crystalline phases: analogues for radioactive waste forms

    International Nuclear Information System (INIS)

    Haaker, R.F.; Ewing, R.C.

    1981-01-01

    Naturally occurring mineral analogues to crystalline phases that are constituents of crystalline radioactive waste forms provide a basis for comparison by which the long-term stability of these phases may be estimated. The crystal structures and the crystal chemistry of the following natural analogues are presented: baddeleyite, hematite, nepheline; pollucite, scheelite;sodalite, spinel, apatite, monazite, uraninite, hollandite-priderite, perovskite, and zirconolite. For each phase in geochemistry, occurrence, alteration and radiation effects are described. A selected bibliography for each phase is included

  7. Naturally occurring crystalline phases: analogues for radioactive waste forms

    Energy Technology Data Exchange (ETDEWEB)

    Haaker, R.F.; Ewing, R.C.

    1981-01-01

    Naturally occurring mineral analogues to crystalline phases that are constituents of crystalline radioactive waste forms provide a basis for comparison by which the long-term stability of these phases may be estimated. The crystal structures and the crystal chemistry of the following natural analogues are presented: baddeleyite, hematite, nepheline; pollucite, scheelite;sodalite, spinel, apatite, monazite, uraninite, hollandite-priderite, perovskite, and zirconolite. For each phase in geochemistry, occurrence, alteration and radiation effects are described. A selected bibliography for each phase is included.

  8. Mineralogical, crystallographic and redox features of the earliest stages of fluid alteration in CM chondrites

    Science.gov (United States)

    Pignatelli, Isabella; Marrocchi, Yves; Mugnaioli, Enrico; Bourdelle, Franck; Gounelle, Matthieu

    2017-07-01

    The CM chondrites represent the largest group of hydrated meteorites and span a wide range of conditions, from less altered (i.e., CM2) down to heavily altered (i.e., CM1). The Paris chondrite is considered the least altered CM and thus enables the earliest stages of aqueous alteration processes to be deciphered. Here, we report results from a nanoscale study of tochilinite/cronstedtite intergrowths (TCIs) in Paris-TCIs being the emblematic secondary mineral assemblages of CM chondrites, formed from the alteration of Fe-Ni metal beads (type-I TCIs) and anhydrous silicates (type-II TCIs). We combined high-resolution transmission electron microscopy, scanning transmission X-ray microscopy and electron diffraction tomography to characterize the crystal structure, crystal chemistry and redox state of TCIs. The data obtained are useful to reconstruct the alteration conditions of Paris and to compare them with those of other meteorites. Our results show that tochilinite in Paris is characterized by a high hydroxide layer content (n = 2.1-2.2) regardless of the silicate precursors. When examined alongside other CMs, it appears that the hydroxide layer and iron contents of tochilinites correlate with the degree of alteration experienced by the chondrites. The Fe3+/ΣFe ratios of TCIs are high: 8-15% in tochilinite, 33-60% in cronstedtite and 70-80% in hydroxides. These observations suggest that alteration of CM chondrites took place under oxidizing conditions that could have been induced by significant H2 release during serpentinization. Similar results were recently reported in CR chondrites (Le Guillou et al., 2015), suggesting that the process(es) controlling the redox state of the secondary mineral assemblages were quite similar in the CM and CR parent bodies despite the different alteration conditions. According to our mineralogical and crystallographic survey, the formation of TCIs in Paris occurred at temperatures lower than 100 °C, under neutral, slightly alkaline

  9. Video processing of remote sensor data applied to uranium exploration in Wyoming

    International Nuclear Information System (INIS)

    Levinson, R.A.; Marrs, R.W.; Crockell, F.

    1979-01-01

    LANDSAT satellite imagery and aerial photography can be used to map areas of altered sandstone associated with roll-front uranium deposits. Image data must be enhanced so that alteration spectral contrasts can be seen, and video image processing is a fast, low-cost, and efficient tool. For LANDSAT data, the 7/4 ratio produces the best enhancement of altered sandstone. The 6/4 ratio is most effective for color infrared aerial photography. Geochemical and mineralogical associations occur in unaltered, altered, and ore roll-front zones. Samples from Pumpkin Buttes show that iron is the primary coloring agent which makes alteration visually detectable. Eh and pH changes associated with passage of a roll front cause oxidation of magnetite and pyrite to hematite, goethite, and limonite in the host sandstone, thereby producing the alteration. Statistical analysis show that the detectability of geochemical and color zonation in host sands is weakened by soil-forming processes. Alteration can only be mapped in areas of thin soil cover and moderate to sparse vegetative cover

  10. rights reserved Geophysical Identification of Hydrothermally Altered

    African Journals Online (AJOL)

    ADOWIE PERE

    Geophysical Identification of Hydrothermally Altered Structures That Favour .... aircraft. Total line kilometers of 36,500 were covered in the survey. Magnetic ... tie lines occur at about 2000 metres interval in the ... visual inspection of the map.

  11. Biological soil crust as a bio-mediator alters hydrological processes in stabilized dune system of the Tengger Desert, China

    Science.gov (United States)

    Li, Xinrong

    2016-04-01

    Biological soil crust (BSC) is a vital component in the stabilized sand dunes with a living cover up to more than 70% of the total, which has been considered as a bio-mediator that directly influences and regulates the sand dune ecosystem processes. However, its influences on soil hydrological processes have been long neglected in Chinese deserts. In this study, BSCs of different successional stages were chose to test their influence on the hydrological processes of stabilized dune, where the groundwater deep exceeds 30m, further to explore why occur the sand-binding vegetation replacement between shrubs and herbs. Our long-term observation (60 years) shows that cyanobacteria crust has been colonized and developed after 3 years since the sand-binding vegetation has been established and dune fixation using planted xerophytic shrubs and made sand barrier (straw-checkerboard) on shifting dune surface, lichen and moss crust occurred after 20 years, and the cover of moss dominated crust could reach 70 % after 50 years. The colonization and development of BSC altered the initial soil water balance of revegetated areas by influencing rainfall infiltration, soil evaporation and dew water entrapment. The results show that BSC obviously reduced the infiltration that occurred during most rainfall events (80%), when rainfall was greater than 5 mm or less than 20 mm. The presence of BSC reduced evaporation of topsoil after small rainfall (<5 mm) because its high proportion of finer particles slowed the evaporation rate, thus keeping the water in the soil surface longer, and crust facilitated topsoil evaporation when rainfall reached 10 mm. The amount of dew entrapment increases with the succession of BSC. Moreover, the effect of the later successional BSC to dew entrapment, rainfall infiltration and evaporation was more obvious than the early successional BSC on stabilized dunes. In general, BSC reduced the amount of rainfall water that reached deeper soil (0.4-3m), which is

  12. Alterations in choice behavior by manipulations of world model.

    Science.gov (United States)

    Green, C S; Benson, C; Kersten, D; Schrater, P

    2010-09-14

    How to compute initially unknown reward values makes up one of the key problems in reinforcement learning theory, with two basic approaches being used. Model-free algorithms rely on the accumulation of substantial amounts of experience to compute the value of actions, whereas in model-based learning, the agent seeks to learn the generative process for outcomes from which the value of actions can be predicted. Here we show that (i) "probability matching"-a consistent example of suboptimal choice behavior seen in humans-occurs in an optimal Bayesian model-based learner using a max decision rule that is initialized with ecologically plausible, but incorrect beliefs about the generative process for outcomes and (ii) human behavior can be strongly and predictably altered by the presence of cues suggestive of various generative processes, despite statistically identical outcome generation. These results suggest human decision making is rational and model based and not consistent with model-free learning.

  13. Petrography, alteration and genesis of iron mineralization in Roshtkhar

    Directory of Open Access Journals (Sweden)

    Habib Biabangard

    2017-07-01

    Full Text Available Introduction Iron mineralization in Roshtkhar is located in 48 Km east of the city of Roshtkhar and south of the Khorasan Razavi province. It is geologically located in the north east of the Lut block and the Khaf-Bardeskan volcano-plutonic belt. The Khaf-Bardeskan belt is an important metallogenic province since it is a host of valuable ore deposits such as the Kuh-e-Zar Au-Spicularite, the Tanourcheh and the Khaf Iron ore deposits (Karimpour and Malekzadeh Shafaroudi, 2007. Iron and Copper mineralization in this belt are known as the hydrothermal, skarn and IOCG types (Karimpour and Malekzadeh Shafaroudi, 2007. IOCG deposits are a new type of magmatic to hydrothermal mineralization in the continental crust (Hitzman et al., 1992. Precambrian marble, Lower Paleozoic schist and metavolcanics are the oldest rocks of the area. The younger units are Oligocene conglomerate, shale and sandstone, Miocene marl and Quaternary deposits. Iron oxides and Cu sulfides are associated with igneous rocks. Fe and Cu mineralization in Roshtkhar has been subject of a few studies such as Yousefi Surani (2006. This study describes the petrography of the host rocks, ore paragenesis, alteration types, geochemistry, genesis and other features of the Fe and Cu mineralization in the Roshtkhar iron. Methods After detailed field studies and sampling, 30 thin sections and 20 polished sections that were prepared from host rocks and ores were studied by conventional petrographic and mineraloghraphic methods in the geology department of the University of Sistan and Baluchestan. 5 samples from the alteration zones were examined by XRD in the Yamagata University in Japan, and 8 samples from the less altered ones were analyzed by XRF and ICP-OES in the Kharazmi University and the Iranian mineral processing research center (IMPRC in Karaj, respectively. The XRF and ICP-OES data are presented in Table 1. Result and discussion The host rocks of the Roshtkhar Iron deposit are diorite

  14. Homeostasis-altering molecular processes as mechanisms of inflammasome activation.

    Science.gov (United States)

    Liston, Adrian; Masters, Seth L

    2017-03-01

    The innate immune system uses a distinct set of germline-encoded pattern recognition receptors (PRRs) to initiate downstream inflammatory cascades. This recognition system is in stark contrast to the adaptive immune system, which relies on highly variable, randomly generated antigen receptors. A key limitation of the innate immune system's reliance on fixed PRRs is its inflexibility in responding to rapidly evolving pathogens. Recent advances in our understanding of inflammasome activation suggest that the innate immune system also has sophisticated mechanisms for responding to pathogens for which there is no fixed PRR. This includes the recognition of debris from dying cells, known as danger-associated molecular patterns (DAMPs), which can directly activate PRRs in a similar manner to pathogen-associated molecular patterns (PAMPs). Distinct from this, emerging data for the inflammasome components NLRP3 (NOD-, LRR- and pyrin domain-containing 3) and pyrin suggest that they do not directly detect molecular patterns, but instead act as signal integrators that are capable of detecting perturbations in cytoplasmic homeostasis, for example, as initiated by infection. Monitoring these perturbations, which we term 'homeostasis-altering molecular processes' (HAMPs), provides potent flexibility in the capacity of the innate immune system to detect evolutionarily novel infections; however, HAMP sensing may also underlie the sterile inflammation that drives chronic inflammatory diseases.

  15. Analysis of the planned post-mining landscape of MIBRAG's open-cast mines with regard to a possible environmental impact of alteration processes in mixed dumps

    International Nuclear Information System (INIS)

    Jolas, P.; Hofmann, B.

    2010-01-01

    There has been an increasing body of knowledge with regard to hydro- and geochemical alteration processes in overburden dumps and their impact on groundwater quality in lignite mining and reclamation operations associated with post-mining landscapes in Germany. The operators of the MIBRAG mines have examined issues regarding alteration processes and how they affect the environment and which opportunities exist to actively influence the dumping process. The objectives were to counteract any possible negative impact of the alteration processes. Special emphasis was on the impact caused by oxidation of sulfur containing minerals. This paper presented an analysis of the situation at United Schleenhain Mine and how it reflects on the work to date for MIBRAG's mines. A future outlook was also presented. Specifically, the paper discussed the development of the United Schleenhain mine and the post-mining landscape. The potential for discharge of substances was also evaluated along with acidification. 1 tab., 5 figs.

  16. Mindfulness Training Alters Emotional Memory Recall Compared to Active Controls: Support for an Emotional Information Processing Model of Mindfulness

    OpenAIRE

    Roberts-Wolfe, Douglas; Sacchet, Matthew D.; Hastings, Elizabeth; Roth, Harold; Britton, Willoughby

    2012-01-01

    Objectives: While mindfulness-based interventions have received widespread application in both clinical and non-clinical populations, the mechanism by which mindfulness meditation improves well-being remains elusive. One possibility is that mindfulness training alters the processing of emotional information, similar to prevailing cognitive models of depression and anxiety. The aim of this study was to investigate the effects of mindfulness training on emotional information processing (i.e., m...

  17. Altered hypothalamic protein expression in a rat model of Huntington's disease.

    Directory of Open Access Journals (Sweden)

    Wei-na Cong

    Full Text Available Huntington's disease (HD is a neurodegenerative disorder, which is characterized by progressive motor impairment and cognitive alterations. Changes in energy metabolism, neuroendocrine function, body weight, euglycemia, appetite function, and circadian rhythm can also occur. It is likely that the locus of these alterations is the hypothalamus. We used the HD transgenic (tg rat model bearing 51 CAG repeats, which exhibits similar HD symptomology as HD patients to investigate hypothalamic function. We conducted detailed hypothalamic proteome analyses and also measured circulating levels of various metabolic hormones and lipids in pre-symptomatic and symptomatic animals. Our results demonstrate that there are significant alterations in HD rat hypothalamic protein expression such as glial fibrillary acidic protein (GFAP, heat shock protein-70, the oxidative damage protein glutathione peroxidase (Gpx4, glycogen synthase1 (Gys1 and the lipid synthesis enzyme acylglycerol-3-phosphate O-acyltransferase 1 (Agpat1. In addition, there are significant alterations in various circulating metabolic hormones and lipids in pre-symptomatic animals including, insulin, leptin, triglycerides and HDL, before any motor or cognitive alterations are apparent. These early metabolic and lipid alterations are likely prodromal signs of hypothalamic dysfunction. Gaining a greater understanding of the hypothalamic and metabolic alterations that occur in HD, could lead to the development of novel therapeutics for early interventional treatment of HD.

  18. Altered Medial Frontal and Superior Temporal Response to Implicit Processing of Emotions in Autism.

    Science.gov (United States)

    Kana, Rajesh K; Patriquin, Michelle A; Black, Briley S; Channell, Marie M; Wicker, Bruno

    2016-01-01

    Interpreting emotional expressions appropriately poses a challenge for individuals with autism spectrum disorder (ASD). In particular, difficulties with emotional processing in ASD are more pronounced in contexts where emotional expressions are subtle, automatic, and reflexive-that is, implicit. In contrast, explicit emotional processing, which requires the cognitive evaluation of an emotional experience, appears to be relatively intact in individuals with ASD. In the present study, we examined the brain activation and functional connectivity differences underlying explicit and implicit emotional processing in age- and IQ-matched adults with (n = 17) and without (n = 15) ASD. Results indicated: (1) significantly reduced levels of brain activation in participants with ASD in medial prefrontal cortex (MPFC) and superior temporal gyrus (STG) during implicit emotion processing; (2) significantly weaker functional connectivity in the ASD group in connections of the MPFC with the amygdala, temporal lobe, parietal lobe, and fusiform gyrus; (3) No group difference in performance accuracy or reaction time; and (4) Significant positive relationship between empathizing ability and STG activity in ASD but not in typically developing participants. These findings suggest that the neural mechanisms underlying implicit, but not explicit, emotion processing may be altered at multiple levels in individuals with ASD. © 2015 International Society for Autism Research, Wiley Periodicals, Inc.

  19. White matter alterations in neurodegenerative and vascular dementia

    International Nuclear Information System (INIS)

    Supprian, T.; Kessler, H.; Falkai, P.; Retz, W.; Roesler, M.; Grunwald, I.; Reith, W.

    2003-01-01

    Due to a significant overlap of the two syndromes, differentiation of degenerative dementia of the Alzheimer-type from vascular dementia may be difficult even when imaging studies are available. White matter changes occur in many patients suffering from Alzheimer's disease. Little is known about the impact of white matter changes on the course and clinical presentation of Alzheimer's disease. High sensitivity of MRI in the detection of white matter alterations may account for over-diagnosing vascular dementia. The clinical significance of white matter alterations in dementia is still a matter of debate. The article reviews current concepts about the role of white matter alterations in dementia. (orig.) [de

  20. Sulphur depletion altered somatic embryogenesis in Theobroma ...

    African Journals Online (AJOL)

    Somatic embryogenesis is a useful tool for Theobroma cacao improvement and propagation. Depending on culture medium composition, different morphogenetic structures (including somatic embryo) occur in response to alteration of genes expression patterns and biochemical changes. The effect of SO42- ion deficiency ...

  1. Effect of primary processing of cereals and legumes on its nutritional quality: A comprehensive review

    Directory of Open Access Journals (Sweden)

    Morteza Oghbaei

    2016-12-01

    Full Text Available Cereals and legumes are important part of dietaries and contribute substantially to nutrient intake of human beings. They are significant source of energy, protein, dietary fiber, vitamins, minerals, and phytochemicals. Primary processing of cereals and legumes is an essential component of their preparation before use. For some grains, dehusking is an essential step, whereas for others, it could be milling the grain into flour. Grains are subjected to certain processing treatments to impart special characteristics and improve organoleptic properties such as expanded cereals. All these treatments result in alteration of their nutritional quality which could either be reduction in nutrients, phytochemicals and antinutrients or an improvement in digestibility or availability of nutrients. It is important to understand these changes occurring in grain nutritional quality on account of pre-processing treatments to select appropriate techniques to obtain maximum nutritional and health benefits. This review attempts to throw light on nutritional alterations occurring in grains due to pre-processing treatments.

  2. Involvement of gut microbial fermentation in the metabolic alterations occurring in n-3 polyunsaturated fatty acids-depleted mice

    Directory of Open Access Journals (Sweden)

    Carpentier Yvon A

    2011-06-01

    Full Text Available Abstract Backround Western diet is characterized by an insufficient n-3 polyunsaturated fatty acid (PUFA consumption which is known to promote the pathogenesis of several diseases. We have previously observed that mice fed with a diet poor in n-3 PUFA for two generations exhibit hepatic steatosis together with a decrease in body weight. The gut microbiota contributes to the regulation of host energy metabolism, due to symbiotic relationship with fermentable nutrients provided in the diet. In this study, we have tested the hypothesis that perturbations of the gut microbiota contribute to the metabolic alterations occurring in mice fed a diet poor in n-3 PUFA for two generations (n-3/- mice. Methods C57Bl/6J mice fed with a control or an n-3 PUFA depleted diet for two generations were supplemented with prebiotic (inulin-type Fructooligosaccharides, FOS, 0.20 g/day/mice during 24 days. Results n-3/-mice exhibited a marked drop in caecum weight, a decrease in lactobacilli and an increase in bifidobacteria in the caecal content as compared to control mice (n-3/+ mice. Dietary supplementation with FOS for 24 days was sufficient to increase caecal weight and bifidobacteria count in both n-3/+ and n-3/-mice. Moreover, FOS increased lactobacilli content in n-3/-mice, whereas it decreased their level in n-3/+ mice. Interestingly, FOS treatment promoted body weight gain in n-3/-mice by increasing energy efficiency. In addition, FOS treatment decreased fasting glycemia and lowered the higher expression of key factors involved in the fatty acid catabolism observed in the liver of n-3/-mice, without lessening steatosis. Conclusions the changes in the gut microbiota composition induced by FOS are different depending on the type of diet. We show that FOS may promote lactobacilli and counteract the catabolic status induced by n-3 PUFA depletion in mice, thereby contributing to restore efficient fat storage.

  3. Chemistry, mineralogy and alteration intensity of hydrothermal altered Mt Unzen conduit rocks (Shimabara/Japan)

    Science.gov (United States)

    Hess, Kai-Uwe; Yilmaz, Tim; Gilg, H. Albert; Janots, Emilie; Mayer, Klaus; Nakada, Setsuya; Dingwell, Donald

    2017-04-01

    Investigations were carried out on hydrothermally altered coherent dacitic dykes samples from (USDP-4) drill core at Mt Unzen stratovolcano (Shimabara/Japan). XRF, XRD, EMPA, C-O-isotope, hot-cathode CL and SEM analysis led to insights concerning chemistry, mineralogy, and intensity and type of alteration as well as the origin of carbonate-precipitating fluids. Additionally a textural characterization of the occurring replacement features in the volcanic conduit rocks was performed. The occurrence of the main secondary phases such as chlorite, pyrite, carbonates, and R1 (Reichweite parameter) illite-smectite and kaolinite group minerals indicate a weak to moderate propylitic to phyllic hydrothermal alteration. The dacitic samples of the dykes show different hydrothermal alteration features: (i) carbonate and chlorite pseudomorphs after hornblende as well as core and zonal textures due to replacement of plagioclase by R1 illite-smectite as well as kaolinite group minerals, (ii) colloform banded fracture fillings and fillings in dissolution vugs, and (iii) chlorite, R1 illite-smectite as well as kaolinite group minerals in the groundmass. Late chlorite veins crosscut precipitates of R1 illite-smectite as well as kaolinite group minerals. Carbonates in fractures and in pseudomorphs after hornblende comprise iron-rich dolomite solid solutions ("ankerite") and calcite. Isotopic values indicate a hydrothermal-magmatic origin for the carbonate formation. The chlorite-carbonate-pyrite index (CCPI) and the Ishikawa alteration index (AI), applied to the investigated samples show significant differences (CCPI=52.7-57.8; AI=36.1-40.6) indicating their different degree of alteration. According to Nakada et al., 2005, the C13 to C16 dykes represent the feeder dyke from the latest eruption (1991-1995) whereas C8 represents an earlier dyke feeder dyke from an older eruption. Weakest alteration, which was obtained in samples C16-1-5 and C13-2-5, correlates with the alteration

  4. Altered processing of rewarding and aversive basic taste stimuli in symptomatic women with anorexia nervosa and bulimia nervosa: An fMRI study.

    Science.gov (United States)

    Monteleone, Alessio Maria; Monteleone, Palmiero; Esposito, Fabrizio; Prinster, Anna; Volpe, Umberto; Cantone, Elena; Pellegrino, Francesca; Canna, Antonietta; Milano, Walter; Aiello, Marco; Di Salle, Francesco; Maj, Mario

    2017-07-01

    Functional magnetic resonance imaging (fMRI) studies have displayed a dysregulation in the way in which the brain processes pleasant taste stimuli in patients with anorexia nervosa (AN) and bulimia nervosa (BN). However, exactly how the brain processes disgusting basic taste stimuli has never been investigated, even though disgust plays a role in food intake modulation and AN and BN patients exhibit high disgust sensitivity. Therefore, we investigated the activation of brain areas following the administration of pleasant and aversive basic taste stimuli in symptomatic AN and BN patients compared to healthy subjects. Twenty underweight AN women, 20 symptomatic BN women and 20 healthy women underwent fMRI while tasting 0.292 M sucrose solution (sweet taste), 0.5 mM quinine hydrochloride solution (bitter taste) and water as a reference taste. In symptomatic AN and BN patients the pleasant sweet stimulus induced a higher activation in several brain areas than that induced by the aversive bitter taste. The opposite occurred in healthy controls. Moreover, compared to healthy controls, AN patients showed a decreased response to the bitter stimulus in the right amygdala and left anterior cingulate cortex, while BN patients showed a decreased response to the bitter stimulus in the right amygdala and left insula. These results show an altered processing of rewarding and aversive taste stimuli in ED patients, which may be relevant for understanding the pathophysiology of AN and BN. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Aging induced ER stress alters sleep and sleep homeostasis

    OpenAIRE

    Brown, Marishka K.; Chan, May T.; Zimmerman, John E.; Pack, Allan I.; Jackson, Nicholas E.; Naidoo, Nirinjini

    2013-01-01

    Alterations in the quality, quantity and architecture of baseline and recovery sleep have been shown to occur during aging. Sleep deprivation induces endoplasmic reticular (ER) stress and upregulates a protective signaling pathway termed the unfolded protein response (UPR). The effectiveness of the adaptive UPR is diminished by age. Previously, we showed that endogenous chaperone levels altered recovery sleep in Drosophila melanogaster. We now report that acute administration of the chemical ...

  6. Sexual Abuse Exposure Alters Early Processing of Emotional Words: Evidence from Event-Related Potentials

    Science.gov (United States)

    Grégoire, Laurent; Caparos, Serge; Leblanc, Carole-Anne; Brisson, Benoit; Blanchette, Isabelle

    2018-01-01

    This study aimed to compare the time course of emotional information processing between trauma-exposed and control participants, using electrophysiological measures. We conceived an emotional Stroop task with two types of words: trauma-related emotional words and neutral words. We assessed the evoked cerebral responses of sexual abuse victims without post-traumatic stress disorder (PTSD) and no abuse participants. We focused particularly on an early wave (C1/P1), the N2pc, and the P3b. Our main result indicated an early effect (55–165 ms) of emotionality, which varied between non-exposed participants and sexual abuse victims. This suggests that potentially traumatic experiences modulate early processing of emotional information. Our findings showing neurobiological alterations in sexual abuse victims (without PTSD) suggest that exposure to highly emotional events has an important impact on neurocognitive function even in the absence of psychopathology. PMID:29379428

  7. Sexual Abuse Exposure Alters Early Processing of Emotional Words: Evidence from Event-Related Potentials

    Directory of Open Access Journals (Sweden)

    Laurent Grégoire

    2018-01-01

    Full Text Available This study aimed to compare the time course of emotional information processing between trauma-exposed and control participants, using electrophysiological measures. We conceived an emotional Stroop task with two types of words: trauma-related emotional words and neutral words. We assessed the evoked cerebral responses of sexual abuse victims without post-traumatic stress disorder (PTSD and no abuse participants. We focused particularly on an early wave (C1/P1, the N2pc, and the P3b. Our main result indicated an early effect (55–165 ms of emotionality, which varied between non-exposed participants and sexual abuse victims. This suggests that potentially traumatic experiences modulate early processing of emotional information. Our findings showing neurobiological alterations in sexual abuse victims (without PTSD suggest that exposure to highly emotional events has an important impact on neurocognitive function even in the absence of psychopathology.

  8. Altered visual information processing systems in bipolar disorder: evidence from visual MMN and P3

    Directory of Open Access Journals (Sweden)

    Toshihiko eMaekawa

    2013-07-01

    Full Text Available Objective: Mismatch negativity (MMN and P3 are unique ERP components that provide objective indices of human cognitive functions such as short-term memory and prediction. Bipolar disorder (BD is an endogenous psychiatric disorder characterized by extreme shifts in mood, energy, and ability to function socially. BD patients usually show cognitive dysfunction, and the goal of this study was to access their altered visual information processing via visual MMN (vMMN and P3 using windmill pattern stimuli.Methods: Twenty patients with BD and 20 healthy controls matched for age, gender, and handedness participated in this study. Subjects were seated in front of a monitor and listened to a story via earphones. Two types of windmill patterns (standard and deviant and white circle (target stimuli were randomly presented on the monitor. All stimuli were presented in random order at 200-ms durations with an 800-ms inter-stimulus interval. Stimuli were presented at 80% (standard, 10% (deviant, and 10% (target probabilities. The participants were instructed to attend to the story and press a button as soon as possible when the target stimuli were presented. Event-related potentials were recorded throughout the experiment using 128-channel EEG equipment. vMMN was obtained by subtracting standard from deviant stimuli responses, and P3 was evoked from the target stimulus.Results: Mean reaction times for target stimuli in the BD group were significantly higher than those in the control group. Additionally, mean vMMN-amplitudes and peak P3-amplitudes were significantly lower in the BD group than in controls.Conclusions: Abnormal vMMN and P3 in patients indicate a deficit of visual information processing in bipolar disorder, which is consistent with their increased reaction time to visual target stimuli.Significance: Both bottom-up and top-down visual information processing are likely altered in BD.

  9. Anaerobic Digestion Alters Copper and Zinc Speciation.

    Science.gov (United States)

    Legros, Samuel; Levard, Clément; Marcato-Romain, Claire-Emmanuelle; Guiresse, Maritxu; Doelsch, Emmanuel

    2017-09-19

    Anaerobic digestion is a widely used organic waste treatment process. However, little is known on how it could alter the speciation of contaminants in organic waste. This study was focused on determining the influence of anaerobic digestion on the speciation of copper and zinc, two metals that generally occur at high concentration in organic waste. Copper and zinc speciation was investigated by X-ray absorption spectroscopy in four different raw organic wastes (predigestion) and their digested counterparts (postdigestion, i.e., digestates). The results highlighted an increase in the digestates of the proportion of amorphous or nanostructured copper sulfides as well as amorphous or nanostructured zinc sulfides and zinc phosphate as compared to raw waste. We therefore suggest that the environmental fate of these elements would be different when spreading either digestates or raw waste on cropland.

  10. Altered structure-function relations of semantic processing in youths with high-functioning autism: a combined diffusion and functional MRI study.

    Science.gov (United States)

    Lo, Yu-Chun; Chou, Tai-Li; Fan, Li-Ying; Gau, Susan Shur-Fen; Chiu, Yen-Nan; Tseng, Wen-Yih Isaac

    2013-12-01

    Deficits in language and communication are among the core symptoms of autism, a common neurodevelopmental disorder with long-term impairment. Despite the striking nature of the autistic language impairment, knowledge about its corresponding alterations in the brain is still evolving. We hypothesized that the dual stream language network is altered in autism, and that this alteration could be revealed by changes in the relationships between microstructural integrity and functional activation. The study recruited 20 right-handed male youths with autism and 20 carefully matched individually, typically developing (TD) youths. Microstructural integrity of the left dorsal and left ventral pathways responsible for language processing and the functional activation of the connected brain regions were investigated by using diffusion spectrum imaging and functional magnetic resonance imaging of a semantic task, respectively. Youths with autism had significantly poorer language function, and lower functional activation in left dorsal and left ventral regions of the language network, compared with TD youths. The TD group showed a significant correlation of the functional activation of the left dorsal region with microstructural integrity of the left ventral pathway, whereas the autism group showed a significant correlation of the functional activation of the left ventral region with microstructural integrity of the left dorsal pathway, and moreover verbal comprehension index was correlated with microstructural integrity of the left ventral pathway. These altered structure-function relationships in autism suggest possible involvement of the dual pathways in supporting deficient semantic processing. © 2013 International Society for Autism Research, Wiley Periodicals, Inc.

  11. Associations between Prenatal and Early Childhood Fish and Processed Food Intake, Conduct Problems, and Co-Occurring Difficulties.

    Science.gov (United States)

    Mesirow, Maurissa Sc; Cecil, Charlotte; Maughan, Barbara; Barker, Edward D

    2017-07-01

    Little is known about early life diet as a risk factor for early-onset persistent conduct problems (EOP CP). To investigate this, we used data from the Avon Longitudinal Study of Parents and Children, a UK-based prospective epidemiological birth cohort. 5727 mother-child pairs (49.9 % boys) monitored since pregnancy (delivery date between 1 April, 1991 and 31 December, 1992) reported intake of fish and processed foods at 32 weeks gestation and, for the child, at 3 years; EOP (n = 666) and Low conduct problem (Low CP, n = 5061) trajectories were measured from 4 to 13 years; hyperactivity and emotional difficulties were assessed in childhood (4-10 years) and early adolescence (12-13 years), in addition to potential confounding factors (family adversity, birth complications, income). Compared to Low CP, mothers of EOP children consumed less fish (p processed food (p processed food at 3 years (p processed food (vs. less than one serving/day, p processed food, and low in fish, associate with an EOP CP trajectory and co-occurring difficulties in early adolescence. As small effect size differences were found, further studies are needed to investigate the long-term impact of early unhealthy diet.

  12. Altered Functional Subnetwork During Emotional Face Processing: A Potential Intermediate Phenotype for Schizophrenia.

    Science.gov (United States)

    Cao, Hengyi; Bertolino, Alessandro; Walter, Henrik; Schneider, Michael; Schäfer, Axel; Taurisano, Paolo; Blasi, Giuseppe; Haddad, Leila; Grimm, Oliver; Otto, Kristina; Dixson, Luanna; Erk, Susanne; Mohnke, Sebastian; Heinz, Andreas; Romanczuk-Seiferth, Nina; Mühleisen, Thomas W; Mattheisen, Manuel; Witt, Stephanie H; Cichon, Sven; Noethen, Markus; Rietschel, Marcella; Tost, Heike; Meyer-Lindenberg, Andreas

    2016-06-01

    Although deficits in emotional processing are prominent in schizophrenia, it has been difficult to identify neural mechanisms related to the genetic risk for this highly heritable illness. Prior studies have not found consistent regional activation or connectivity alterations in first-degree relatives compared with healthy controls, suggesting that a more comprehensive search for connectomic biomarkers is warranted. To identify a potential systems-level intermediate phenotype linked to emotion processing in schizophrenia and to examine the psychological association, task specificity, test-retest reliability, and clinical validity of the identified phenotype. The study was performed in university research hospitals from June 1, 2008, through December 31, 2013. We examined 58 unaffected first-degree relatives of patients with schizophrenia and 94 healthy controls with an emotional face-matching functional magnetic resonance imaging paradigm. Test-retest reliability was analyzed with an independent sample of 26 healthy participants. A clinical association study was performed in 31 patients with schizophrenia and 45 healthy controls. Data analysis was performed from January 1 to September 30, 2014. Conventional amygdala activity and seeded connectivity measures, graph-based global and local network connectivity measures, Spearman rank correlation, intraclass correlation, and gray matter volumes. Among the 152 volunteers included in the relative-control sample, 58 were unaffected first-degree relatives of patients with schizophrenia (mean [SD] age, 33.29 [12.56]; 38 were women), and 94 were healthy controls without a first-degree relative with mental illness (mean [SD] age, 32.69 [10.09] years; 55 were women). A graph-theoretical connectivity approach identified significantly decreased connectivity in a subnetwork that primarily included the limbic cortex, visual cortex, and subcortex during emotional face processing (cluster-level P corrected for familywise error =

  13. White matter alterations in temporal lobe epilepsy

    Science.gov (United States)

    Diniz, P. B.; Salmon, C. E.; Velasco, T. R.; Sakamoto, A. C.; Leite, J. P.; Santos, A. C.

    2011-03-01

    In This study, we used Fractional anisotropy (FA), mean diffusivity (D), parallel diffusivity (D//) and perpendicular diffusivity (D), to localize the regions where occur axonal lesion and demyelization. TBSS was applied to analyze the FA data. After, the regions with alteration were studied with D, D// and D maps. Patients exhibited widespread degradation of FA. With D, D// and D maps analysis we found alterations in corpus callosum, corticospinal tract, fornix, internal capsule, corona radiate, Sagittal stratum, cingulum, fronto-occipital fasciculus and uncinate fasciculus. Our results are consistent with the hypothesis that exist demyelization and axonal damage in patients with TLE.

  14. Transmission Electron Microscope Observations of Phyllosilicate Development During Experimental Aqueous Alteration of Allende

    Science.gov (United States)

    Jones, C. L.; Brearley, A. J.

    2000-01-01

    Samples of Allende have been altered hydrothermally under oxidizing conditions at 200 C. TEM studies show that within 30 days evidence of replacement of matrix olivines by fine-grained serpentine is present and by 90 days complete alteration of many grains has occurred.

  15. Stable isotopic and mineralogical studies of hydrothermal alteration at Arima Spa, Southwest Japan

    International Nuclear Information System (INIS)

    Masuda, Harue; Osaka City Univ.; Sakai, Hitoshi; Chiba, Hitoshi; Matsuhisa, Yukihiro; Nakamura, Takeshi

    1986-01-01

    The waters of Arima Spa, Southwest Japan, have high salinity (Cl = 54 g/kg) and high isotopic ratios (deltaD = -32, and delta 18 O = +10 per mille), and issue from shallow wells drilled into altered rhyolitic pyroclastic rocks of Cretaceous age. Alteration of the host rocks occurred in two stages. The earlier regional alteration stage is characterized by the presence of 2M- and 1M-type muscovite, albite, chlorite, calcite and epidote, whereas muscovite and Fe-chlorite formation at the expense of partly albitized plagioclase and altered biotite or hornblende occurred in the following hydrothermal stage. Pyrite, sphalerite, galena and siderite are present in the central part of the hydrothermal alteration zone. Oxygen and hydrogen isotopic ratios of secondary muscovite show that regional alteration proceeded under the meteoric circulation, and that the hydrothermal fluid for the second stage had chemical and stable isotopic characteristics of non-meteoric origin similar to the present-day Arima brine. The oxygen and to a lesser extent the hydrogen isotopic ratios of the muscovite rapidly decrease with increasing distance from the central zone of hydrothermal alteration. The isotopic variation is best interpreted as reflecting rapidly decreasing fluid/rock ratios with increasing distance of fluid penetration from the narrow hydrothermal alteration zone into the surrounding area. The results are discussed. (author)

  16. Analysis of the planned post-mining landscape of MIBRAG's open-cast mines with regard to a possible environmental impact of alteration processes in mixed dumps

    Energy Technology Data Exchange (ETDEWEB)

    Jolas, P.; Hofmann, B. [Mitteldeutsche Braunkohlengesellschaft, Theissen (Germany)

    2010-07-01

    There has been an increasing body of knowledge with regard to hydro- and geochemical alteration processes in overburden dumps and their impact on groundwater quality in lignite mining and reclamation operations associated with post-mining landscapes in Germany. The operators of the MIBRAG mines have examined issues regarding alteration processes and how they affect the environment and which opportunities exist to actively influence the dumping process. The objectives were to counteract any possible negative impact of the alteration processes. Special emphasis was on the impact caused by oxidation of sulfur containing minerals. This paper presented an analysis of the situation at United Schleenhain Mine and how it reflects on the work to date for MIBRAG's mines. A future outlook was also presented. Specifically, the paper discussed the development of the United Schleenhain mine and the post-mining landscape. The potential for discharge of substances was also evaluated along with acidification. 1 tab., 5 figs.

  17. Raman-Mössbauer-XRD studies of selected samples from "Los Azulejos" outcrop: A possible analogue for assessing the alteration processes on Mars

    Science.gov (United States)

    Lalla, E. A.; Sanz-Arranz, A.; Lopez-Reyes, G.; Sansano, A.; Medina, J.; Schmanke, D.; Klingelhoefer, G.; Rodríguez-Losada, J. A.; Martínez-Frías, J.; Rull, F.

    2016-06-01

    The outcrop of "Los Azulejos" is visible at the interior of the Cañadas Caldera in Tenerife Island (Spain). It exhibits a great variety of alteration processes that could be considered as terrestrial analogue for several geological processes on Mars. This outcrop is particularly interesting due to the content of clays, zeolite, iron oxides, and sulfates corresponding to a hydrothermal alteration catalogued as "Azulejos" type alteration. A detailed analysis by portable and laboratory Raman systems as well as other different techniques such as X-ray diffraction (XRD) and Mössbauer spectroscopy has been carried out (using twin-instruments from Martian lander missions: Mössbauer spectrometer MIMOS-II from the NASA-MER mission of 2001 and the XRD diffractometer from the NASA-MSL Curiosity mission of 2012). The mineral identification presents the following mineral species: magnetite, goethite, hematite, anatase, rutile, quartz, gregoryite, sulfate (thenardite and hexahydrite), diopside, feldspar, analcime, kaolinite and muscovite. Moreover, the in-situ Raman and Micro-Raman measurements have been performed in order to compare the capabilities of the portable system specially focused for the next ESA Exo-Mars mission. The mineral detection confirms the sub-aerial alteration on the surface and the hydrothermal processes by the volcanic fluid circulations in the fresh part. Therefore, the secondary more abundant mineralization acts as the color agent of the rocks. Thus, the zeolite-illite group is the responsible for the bluish coloration, as well as the feldspars and carbonates for the whitish and the iron oxide for the redish parts. The XRD system was capable to detect a minor proportion of pyroxene, which is not visible by Raman and Mössbauer spectroscopy due to the "Azulejos" alteration of the parent material on the outcrop. On the other hand, Mössbauer spectroscopy was capable of detecting different types of iron-oxides (Fe3+/2+-oxide phases). These analyses

  18. [Description of the mental processes occurring during clinical reasoning].

    Science.gov (United States)

    Pottier, P; Planchon, B

    2011-06-01

    Clinical reasoning is a highly complex system with multiple inter-dependent mental activities. Gaining a better understanding of those cognitive processes has two practical implications: for physicians, being able to analyse their own reasoning method may prove to be helpful in diagnostic dead end; for medical teachers, identifying problem-solving strategies used by medical students may foster an appropriate individual feed-back aiming at improving their clinical reasoning skills. On the basis of a detailed literature review, the main diagnostic strategies and their related pattern of mental processes are described and illustrated with a concrete example, going from the patient's complaint to the chosen solution. Inductive, abductive and deductive diagnostic approaches are detailed. Different strategies for collecting data (exhaustive or oriented) and for problem-building are described. The place of problem solving strategies such as pattern-recognition, scheme inductive process, using of clinical script, syndrome grouping and mental hypotheses test is considered. This work aims at breaking up mental activities in process within clinical reasoning reminding that expert reasoning is characterised by the ability to use and structure the whole of these activities in a coherent system, using combined strategies in order to guarantee a better accuracy of their diagnosis. Copyright © 2010 Société nationale française de médecine interne (SNFMI). Published by Elsevier SAS. All rights reserved.

  19. Is Neural Processing of Negative Stimuli Altered in Addiction Independent of Drug Effects? Findings From Drug-Naïve Youth with Internet Gaming Disorder.

    Science.gov (United States)

    Yip, Sarah W; Gross, James J; Chawla, Megha; Ma, Shan-Shan; Shi, Xing-Hui; Liu, Lu; Yao, Yuan-Wei; Zhu, Lei; Worhunsky, Patrick D; Zhang, Jintao

    2018-05-01

    Difficulties in emotion regulation are commonly reported among individuals with alcohol and drug addictions and contribute to the acquisition and maintenance of addictive behaviors. Alterations in neural processing of negative affective stimuli have further been demonstrated among individuals with addictions. However, it is unclear whether these alterations are a general feature of addictions or are a result of prolonged exposure to drugs of abuse. To test the hypothesis of altered negative affect processing independent of drug effects, this study assessed neural function among drug-naïve youth with a behavioral addiction-Internet gaming disorder (IGD). Fifty-six young adults (28 with IGD, 28 matched controls) participated in fMRI scanning during performance of a well-validated emotion regulation task. Between-group differences in neural activity during task performance were assessed using a whole-brain, mixed-effects ANOVA with correction for multiple comparisons at currently recommended thresholds (voxel-level peffects.

  20. Video processing of remote sensor data applied to uranium exploration in Wyoming. [Roll-front U deposits

    Energy Technology Data Exchange (ETDEWEB)

    Levinson, R.A.; Marrs, R.W.; Crockell, F.

    1979-06-30

    LANDSAT satellite imagery and aerial photography can be used to map areas of altered sandstone associated with roll-front uranium deposits. Image data must be enhanced so that alteration spectral contrasts can be seen, and video image processing is a fast, low-cost, and efficient tool. For LANDSAT data, the 7/4 ratio produces the best enhancement of altered sandstone. The 6/4 ratio is most effective for color infrared aerial photography. Geochemical and mineralogical associations occur in unaltered, altered, and ore roll-front zones. Samples from Pumpkin Buttes show that iron is the primary coloring agent which makes alteration visually detectable. Eh and pH changes associated with passage of a roll front cause oxidation of magnetite and pyrite to hematite, goethite, and limonite in the host sandstone, thereby producing the alteration. Statistical analysis show that the detectability of geochemical and color zonation in host sands is weakened by soil-forming processes. Alteration can only be mapped in areas of thin soil cover and moderate to sparse vegetative cover.

  1. Alterations in the inferior longitudinal fasciculus in autism and associations with visual processing: a diffusion-weighted MRI study.

    Science.gov (United States)

    Boets, Bart; Van Eylen, Lien; Sitek, Kevin; Moors, Pieter; Noens, Ilse; Steyaert, Jean; Sunaert, Stefan; Wagemans, Johan

    2018-01-01

    One of the most reported neural features of autism spectrum disorder (ASD) is the alteration of multiple long-range white matter fiber tracts, as assessed by diffusion-weighted imaging and indexed by reduced fractional anisotropy (FA). Recent methodological advances, however, have shown that this same pattern of reduced FA may be an artifact resulting from excessive head motion and poorer data quality and that aberrant structural connectivity in children with ASD is confined to the right inferior longitudinal fasciculus (ILF). This study aimed at replicating the observation of reduced FA along the right ILF in ASD, while controlling for group differences in head motion and data quality. In addition, we explored associations between reduced FA in the right ILF and quantitative ASD characteristics, and the involvement of the right ILF in visual processing, which is known to be altered in ASD. Global probabilistic tractography was performed on diffusion-weighted imaging data of 17 adolescent boys with ASD and 17 typically developing boys, matched for age, performance IQ, handedness, and data quality. Four tasks were administered to measure various aspects of visual information processing, together with questionnaires assessing ASD characteristics. Group differences were examined and the neural data were integrated with previously published findings using Bayesian statistics to quantify evidence for replication and to pool data and thus increase statistical power. (Partial) correlations were calculated to investigate associations between measures. The ASD group showed consistently reduced FA only in the right ILF and slower performance on the visual search task. Bayesian statistics pooling data across studies confirmed that group differences in FA were confined to the right ILF only, with the evidence for altered FA in the left ILF being indecisive. Lower FA in the right ILF tended to covary with slower visual search and a more fragmented part-oriented processing style

  2. Motor sequence learning occurs despite disrupted visual and proprioceptive feedback

    Directory of Open Access Journals (Sweden)

    Boyd Lara A

    2008-07-01

    Full Text Available Abstract Background Recent work has demonstrated the importance of proprioception for the development of internal representations of the forces encountered during a task. Evidence also exists for a significant role for proprioception in the execution of sequential movements. However, little work has explored the role of proprioceptive sensation during the learning of continuous movement sequences. Here, we report that the repeated segment of a continuous tracking task can be learned despite peripherally altered arm proprioception and severely restricted visual feedback regarding motor output. Methods Healthy adults practiced a continuous tracking task over 2 days. Half of the participants experienced vibration that altered proprioception of shoulder flexion/extension of the active tracking arm (experimental condition and half experienced vibration of the passive resting arm (control condition. Visual feedback was restricted for all participants. Retention testing was conducted on a separate day to assess motor learning. Results Regardless of vibration condition, participants learned the repeated segment demonstrated by significant improvements in accuracy for tracking repeated as compared to random continuous movement sequences. Conclusion These results suggest that with practice, participants were able to use residual afferent information to overcome initial interference of tracking ability related to altered proprioception and restricted visual feedback to learn a continuous motor sequence. Motor learning occurred despite an initial interference of tracking noted during acquisition practice.

  3. Industries processing naturally occurring radioactive materials: twenty years of emission data in the Netherlands

    International Nuclear Information System (INIS)

    Tanzi, C.P.

    2008-01-01

    This paper provides a review of the dose assessment of discharges to air of two industries processing NORM (Naturally Occurring Radioactive Materials) in the Netherlands. An industrial plant producing elemental phosphorus (thermal process, unique within Europe) reports since 1987 its emission data to the Dutch Ministry of the Environment (VROM: Ministry of Housing, Spatial Planning and the Environment). This plant accounts for the highest release of Po-210 to air in the Netherlands, with a yearly average of approximately 500 GBq. Other significant NORM discharges to air arise from an industrial plant with blast-furnaces for steel production. Yearly discharges fall under permit, and are reported, since 1993. RIVM, the National Institute for Public Health and the Environment, is tasked by the Ministry to assess the dose to the general public arising from these discharges to air. Air transport modelling is used to determine both air concentration (for inhalation exposure) and deposition rate of the radionuclides. A (conservative) committed ingestion dose is determined by modelling the uptake of radionuclides from contaminated farmland, and assuming a food basket to be fairly representative for the population of the Netherlands. Discharges to water in the Netherlands have decreased in the past twenty years, due both to the closure of two phosphoric acid plants a decade ago and the improved treatment of waste fluids by other NORM industries. The collective dose assessed from discharges to air since 1987 is presented here. (author)

  4. Tochilinite: A Sensitive Indicator of Alteration Conditions on the CM Asteroidal Parent Body

    Science.gov (United States)

    Browning, L. B.; Bourcier, W. L.

    1996-03-01

    Each CM chondrite experienced a different degree of aqueous alteration. As a group, then, these meteorites preserve tangible evidence of asteroidal reactions that were interrupted at many different stages of completion. Geochemical modeling of CM reaction progress should elucidate the nature of the accreted CM materials and the specific types of asteroidal processes and conditions that subsequently influenced them. However, most of the minerals in CM chondrites are stable under a wide range of environmental conditions, which hinders efforts to capitalize on the diverse degree of CM alteration. Petrologic evidence suggests that Fe-rich tochilinite, the widespread mineralic component of CM chondrites previously referred to as "poorly characterized phase (PCP)", may be the most sensitive indicator of the conditions of CM alteration. This possibility has not previously been explored because thermodynamic data for tochilinite are lacking. We have estimated the thermodynamic properties of tochilinite from mixing equations and then calculated its stability limits with associated non-silicate phases as a function of PS2, PO2, and PCO2. The resultant phase relations : a) are consistent with mineral association in CM chondrites, b) indicate that the CM fluids were S-depleted and extremely reducing, c) imply the possibility of H2 gas seeps on the CM parent body, and d) suggest that the alteration of CM materials occurred at significant asteroidal depths.

  5. Distinct genetic alterations in colorectal cancer.

    Directory of Open Access Journals (Sweden)

    Hassan Ashktorab

    Full Text Available BACKGROUND: Colon cancer (CRC development often includes chromosomal instability (CIN leading to amplifications and deletions of large DNA segments. Epidemiological, clinical, and cytogenetic studies showed that there are considerable differences between CRC tumors from African Americans (AAs and Caucasian patients. In this study, we determined genomic copy number aberrations in sporadic CRC tumors from AAs, in order to investigate possible explanations for the observed disparities. METHODOLOGY/PRINCIPAL FINDINGS: We applied genome-wide array comparative genome hybridization (aCGH using a 105k chip to identify copy number aberrations in samples from 15 AAs. In addition, we did a population comparative analysis with aCGH data in Caucasians as well as with a widely publicized list of colon cancer genes (CAN genes. There was an average of 20 aberrations per patient with more amplifications than deletions. Analysis of DNA copy number of frequently altered chromosomes revealed that deletions occurred primarily in chromosomes 4, 8 and 18. Chromosomal duplications occurred in more than 50% of cases on chromosomes 7, 8, 13, 20 and X. The CIN profile showed some differences when compared to Caucasian alterations. CONCLUSIONS/SIGNIFICANCE: Chromosome X amplification in male patients and chromosomes 4, 8 and 18 deletions were prominent aberrations in AAs. Some CAN genes were altered at high frequencies in AAs with EXOC4, EPHB6, GNAS, MLL3 and TBX22 as the most frequently deleted genes and HAPLN1, ADAM29, SMAD2 and SMAD4 as the most frequently amplified genes. The observed CIN may play a distinctive role in CRC in AAs.

  6. Canine osteosarcoma: a naturally occurring disease to inform pediatric oncology.

    Science.gov (United States)

    Fenger, Joelle M; London, Cheryl A; Kisseberth, William C

    2014-01-01

    Osteosarcoma (OSA) is the most common form of malignant bone cancer in children and dogs, although the disease occurs in dogs approximately 10 times more frequently than in people. Multidrug chemotherapy and aggressive surgical techniques have improved survival; however, new therapies for OSA are critical, as little improvement in survival times has been achieved in either dogs or people over the past 15 years, even with significant efforts directed at the incorporation of novel therapeutic approaches. Both clinical and molecular evidence suggests that human and canine OSA share many key features, including tumor location, presence of microscopic metastatic disease at diagnosis, development of chemotherapy-resistant metastases, and altered expression/activation of several proteins (e.g. Met, ezrin, phosphatase and tensin homolog, signal transducer and activator of transcription 3), and p53 mutations, among others. Additionally, canine and pediatric OSA exhibit overlapping transcriptional profiles and shared DNA copy number aberrations, supporting the notion that these diseases are similar at the molecular level. This review will discuss the similarities between pediatric and canine OSA with regard to histology, biologic behavior, and molecular genetic alterations that indicate canine OSA is a relevant, spontaneous, large animal model of the pediatric disease and outline how the study of naturally occurring OSA in dogs will offer additional insights into the biology and future treatment of this disease in both children and dogs. © The Author 2014. Published by Oxford University Press on behalf of the Institute for Laboratory Animal Research. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  7. Sulfur and carbon geochemistry of the Santa Elena peridotites: Comparing oceanic and continental processes during peridotite alteration

    Science.gov (United States)

    Schwarzenbach, Esther M.; Gill, Benjamin C.; Gazel, Esteban; Madrigal, Pilar

    2016-05-01

    Ultramafic rocks exposed on the continent serve as a window into oceanic and continental processes of water-peridotite interaction, so called serpentinization. In both environments there are active carbon and sulfur cycles that contain abiogenic and biogenic processes, which are eventually imprinted in the geochemical signatures of the basement rocks and the calcite and magnesite deposits associated with fluids that issue from these systems. Here, we present the carbon and sulfur geochemistry of ultramafic rocks and carbonate deposits from the Santa Elena ophiolite in Costa Rica. The aim of this study is to leverage the geochemistry of the ultramafic sequence and associated deposits to distinguish between processes that were dominant during ocean floor alteration and those dominant during low-temperature, continental water-peridotite interaction. The peridotites are variably serpentinized with total sulfur concentrations up to 877 ppm that is typically dominated by sulfide over sulfate. With the exception of one sample the ultramafic rocks are characterized by positive δ34Ssulfide (up to + 23.1‰) and δ34Ssulfate values (up to + 35.0‰). Carbon contents in the peridotites are low and are isotopically distinct from typical oceanic serpentinites. In particular, δ13C of the inorganic carbon suggests that the carbon is not derived from seawater, but rather the product of the interaction of meteoric water with the ultramafic rocks. In contrast, the sulfur isotope data from sulfide minerals in the peridotites preserve evidence for interaction with a hydrothermal fluid. Specifically, they indicate closed system abiogenic sulfate reduction suggesting that oceanic serpentinization occurred with limited input of seawater. Overall, the geochemical signatures preserve evidence for both oceanic and continental water-rock interaction with the majority of carbon (and possibly sulfate) being incorporated during continental water-rock interaction. Furthermore, there is

  8. Anatomical alterations of the visual motion processing network in migraine with and without aura.

    Directory of Open Access Journals (Sweden)

    Cristina Granziera

    2006-10-01

    Full Text Available Patients suffering from migraine with aura (MWA and migraine without aura (MWoA show abnormalities in visual motion perception during and between attacks. Whether this represents the consequences of structural changes in motion-processing networks in migraineurs is unknown. Moreover, the diagnosis of migraine relies on patient's history, and finding differences in the brain of migraineurs might help to contribute to basic research aimed at better understanding the pathophysiology of migraine.To investigate a common potential anatomical basis for these disturbances, we used high-resolution cortical thickness measurement and diffusion tensor imaging (DTI to examine the motion-processing network in 24 migraine patients (12 with MWA and 12 MWoA and 15 age-matched healthy controls (HCs. We found increased cortical thickness of motion-processing visual areas MT+ and V3A in migraineurs compared to HCs. Cortical thickness increases were accompanied by abnormalities of the subjacent white matter. In addition, DTI revealed that migraineurs have alterations in superior colliculus and the lateral geniculate nucleus, which are also involved in visual processing.A structural abnormality in the network of motion-processing areas could account for, or be the result of, the cortical hyperexcitability observed in migraineurs. The finding in patients with both MWA and MWoA of thickness abnormalities in area V3A, previously described as a source in spreading changes involved in visual aura, raises the question as to whether a "silent" cortical spreading depression develops as well in MWoA. In addition, these experimental data may provide clinicians and researchers with a noninvasively acquirable migraine biomarker.

  9. Cellular hyper-excitability caused by mutations that alter the activation process of voltage-gated sodium channels

    Directory of Open Access Journals (Sweden)

    Mohamed-Yassine eAMAROUCH

    2015-02-01

    Full Text Available Voltage-gated sodium channels (Nav are widely expressed as macro-molecular complexes in both excitable and non-excitable tissues. In excitable tissues, the upstroke of the action potential is the result of the passage of a large and rapid influx of sodium ions through these channels. NaV dysfunction has been associated with an increasingly wide range of neurological, muscular and cardiac disorders. The purpose of this review is to summarize the recently identified sodium channel mutations that are linked to hyper-excitability phenotypes and associated with the alteration of the activation process of voltage gated sodium channels. Indeed, several clinical manifestations that demonstrate an alteration of tissue excitability were recently shown to be strongly associated with the presence of mutations that affect the activation process of the voltage-gated sodium channels. These emerging genotype-phenotype correlations have expanded the clinical spectrum of sodium channelopathies to include disorders which feature a hyper-excitability phenotype that may or may not be associated with a cardiomyopathy. The p.I141V mutation in SCN4A and SCN5A, as well as its homologous p.I136V mutation in SCN9A, are interesting examples of mutations that have been linked to inherited hyperexcitability myotonia, exercise-induced polymorphic ventricular arrhythmias and erythromelalgia, respectively. Regardless of which sodium channel isoform is investigated, the substitution of the isoleucine to valine in the locus 141 induces similar modifications in the biophysical properties of the voltage-gated sodium channels by shifting the voltage-dependence of steady state activation towards more negative potentials.

  10. Altered Global Signal Topography in Schizophrenia.

    Science.gov (United States)

    Yang, Genevieve J; Murray, John D; Glasser, Matthew; Pearlson, Godfrey D; Krystal, John H; Schleifer, Charlie; Repovs, Grega; Anticevic, Alan

    2017-11-01

    Schizophrenia (SCZ) is a disabling neuropsychiatric disease associated with disruptions across distributed neural systems. Resting-state functional magnetic resonance imaging has identified extensive abnormalities in the blood-oxygen level-dependent signal in SCZ patients, including alterations in the average signal over the brain-i.e. the "global" signal (GS). It remains unknown, however, if these "global" alterations occur pervasively or follow a spatially preferential pattern. This study presents the first network-by-network quantification of GS topography in healthy subjects and SCZ patients. We observed a nonuniform GS contribution in healthy comparison subjects, whereby sensory areas exhibited the largest GS component. In SCZ patients, we identified preferential GS representation increases across association regions, while sensory regions showed preferential reductions. GS representation in sensory versus association cortices was strongly anti-correlated in healthy subjects. This anti-correlated relationship was markedly reduced in SCZ. Such shifts in GS topography may underlie profound alterations in neural information flow in SCZ, informing development of pharmacotherapies. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  11. The genetic alteration of p53 in esophageal cancer

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Jae Il; Baik, Hee Jong; Kim, Chang Min; Kim, Mi Hee [Korea Cancer Center Hospital, Seoul (Korea, Republic of)

    1996-01-01

    Genetic alterations in the p53 gene have been detected in various human malignancies, and its alterations inactive the function of p53 as a tumor suppressor. Point mutation and gene deletion are the main mechanisms of p53 inactivation. To determine the incidence of genetic alteration of p53 and their clinical implications in Korean patients of esophageal cancer, we investigated p53 alterations in 26 esophageal cancer tissues paired with its normal tissue by Southern blot analysis, PCR-SSCP, and direct sequencing. Allelic loss of chromosome 17p occurred in 12 out of 21 informative cases(57%) by Southern blot analysis, and 16 cases showed mobility shift in PCR-SSCP, so overall incidence of p53 gene alterations was 77%(20/26). The mutations detected was randomly dispersed over exon4-8 and was frequently G-T transversion and C:T transitions. Three identical mutations were clustered at codon 213 suggested the same etiologic agents in this cases. The p53 gene alterations play a significant role in the development of esophageal cancers, however, no relationship between p53 mutation and clinical data was detected so far. 9 refs. (Author).

  12. Heterologous expression of oxytetracycline biosynthetic gene cluster in Streptomyces venezuelae WVR2006 to improve production level and to alter fermentation process.

    Science.gov (United States)

    Yin, Shouliang; Li, Zilong; Wang, Xuefeng; Wang, Huizhuan; Jia, Xiaole; Ai, Guomin; Bai, Zishang; Shi, Mingxin; Yuan, Fang; Liu, Tiejun; Wang, Weishan; Yang, Keqian

    2016-12-01

    Heterologous expression is an important strategy to activate biosynthetic gene clusters of secondary metabolites. Here, it is employed to activate and manipulate the oxytetracycline (OTC) gene cluster and to alter OTC fermentation process. To achieve these goals, a fast-growing heterologous host Streptomyces venezuelae WVR2006 was rationally selected among several potential hosts. It shows rapid and dispersed growth and intrinsic high resistance to OTC. By manipulating the expression of two cluster-situated regulators (CSR) OtcR and OtrR and precursor supply, the OTC production level was significantly increased in this heterologous host from 75 to 431 mg/l only in 48 h, a level comparable to the native producer Streptomyces rimosus M4018 in 8 days. This work shows that S. venezuelae WVR2006 is a promising chassis for the production of secondary metabolites, and the engineered heterologous OTC producer has the potential to completely alter the fermentation process of OTC production.

  13. Spaceflight induces both transient and heritable alterations in DNA methylation and gene expression in rice (Oryza sativa L.)

    Energy Technology Data Exchange (ETDEWEB)

    Ou Xiufang [Key Laboratory of Molecular Epigenetic of MOE and Institute of Genetics and Cytology, Northeast Normal University, Changchun 130024 (China); Long Likun [Inspection and Quarantine Technology Centre of Zhongshan Entry-Exit Inspection and Quarantine Bureau, Zhongshan 528400, Guangdong Province (China); Zhang Yunhong; Xue Yiqun; Liu Jingchun; Lin Xiuyun [Key Laboratory of Molecular Epigenetic of MOE and Institute of Genetics and Cytology, Northeast Normal University, Changchun 130024 (China); Liu Bao [Key Laboratory of Molecular Epigenetic of MOE and Institute of Genetics and Cytology, Northeast Normal University, Changchun 130024 (China)], E-mail: baoliu6677@yahoo.com.cn

    2009-03-09

    Spaceflight represents a complex environmental condition in which several interacting factors such as cosmic radiation, microgravity and space magnetic fields are involved, which may provoke stress responses and jeopardize genome integrity. Given the inherent property of epigenetic modifications to respond to intrinsic as well as external perturbations, it is conceivable that epigenetic markers like DNA methylation may undergo alterations in response to spaceflight. We report here that extensive alteration in both DNA methylation and gene expression occurred in rice plants subjected to a spaceflight, as revealed by a set of characterized sequences including 6 transposable elements (TEs) and 11 cellular genes. We found that several features characterize the alterations: (1) All detected alterations are hypermethylation events; (2) whereas alteration in both CG and CNG methylation occurred in the TEs, only alteration in CNG methylation occurred in the cellular genes; (3) alteration in expression includes both up- and down-regulations, which did not show a general correlation with alteration in methylation; (4) altered methylation patterns in both TEs and cellular genes are heritable to progenies at variable frequencies; however, stochastic reversion to wild-type patterns and further de novo changes in progenies are also apparent; and (5) the altered expression states in both TEs and cellular genes are also heritable to selfed progenies but with markedly lower transmission frequencies than altered DNA methylation states. Furthermore, we found that a set of genes encoding for the various putative DNA methyltransferases, 5-methylcytosine DNA glycosylases, the SWI/SNF chromatin remodeller (DDM1) and siRNA-related proteins are extremely sensitive to perturbation by spaceflight, which might be an underlying cause for the altered methylation patterns in the space-flown plants. We discuss implications of spaceflight-induced epigenetic variations with regard to health safety

  14. Spaceflight induces both transient and heritable alterations in DNA methylation and gene expression in rice (Oryza sativa L.)

    International Nuclear Information System (INIS)

    Ou Xiufang; Long Likun; Zhang Yunhong; Xue Yiqun; Liu Jingchun; Lin Xiuyun; Liu Bao

    2009-01-01

    Spaceflight represents a complex environmental condition in which several interacting factors such as cosmic radiation, microgravity and space magnetic fields are involved, which may provoke stress responses and jeopardize genome integrity. Given the inherent property of epigenetic modifications to respond to intrinsic as well as external perturbations, it is conceivable that epigenetic markers like DNA methylation may undergo alterations in response to spaceflight. We report here that extensive alteration in both DNA methylation and gene expression occurred in rice plants subjected to a spaceflight, as revealed by a set of characterized sequences including 6 transposable elements (TEs) and 11 cellular genes. We found that several features characterize the alterations: (1) All detected alterations are hypermethylation events; (2) whereas alteration in both CG and CNG methylation occurred in the TEs, only alteration in CNG methylation occurred in the cellular genes; (3) alteration in expression includes both up- and down-regulations, which did not show a general correlation with alteration in methylation; (4) altered methylation patterns in both TEs and cellular genes are heritable to progenies at variable frequencies; however, stochastic reversion to wild-type patterns and further de novo changes in progenies are also apparent; and (5) the altered expression states in both TEs and cellular genes are also heritable to selfed progenies but with markedly lower transmission frequencies than altered DNA methylation states. Furthermore, we found that a set of genes encoding for the various putative DNA methyltransferases, 5-methylcytosine DNA glycosylases, the SWI/SNF chromatin remodeller (DDM1) and siRNA-related proteins are extremely sensitive to perturbation by spaceflight, which might be an underlying cause for the altered methylation patterns in the space-flown plants. We discuss implications of spaceflight-induced epigenetic variations with regard to health safety

  15. Physicochemical processes occurring under action of ionizing radiation in sarcophagus

    International Nuclear Information System (INIS)

    Azarov, S.I.; Pshenichny, V.A.; Vilenskaya, L.N.; Korchevnaya, O.V.; Martseniuk, L.S.

    1998-01-01

    The result of analysis of environment ionization process inside Sarcophagus owing to alpha-, beta- and gamma-radiation processes with forming of ions. It is shown that as a result of ionization and physicochemical transformations gaseous mixtures, which are dangerous for personnel's health and can influence upon general technical safety of Sarcophagus, can release into atmosphere

  16. From Hills to Holes: How Climate Change and Mining are Altering Runoff Processes in Canada

    Science.gov (United States)

    Carey, S. K.

    2015-12-01

    Canadian environments are under considerable pressure from both climate and land-use change. While warming temperatures are widespread and amplified in the north, surface mining has resulted in large-scale landscape disturbance. How these changes affect catchment response is profound, fundamentally altering the cycling and delivery of water and geochemicals to the drainage network. In permafrost-underlain environments, coupled mass and energy processes control runoff response, and as ground thaw increases, new subsurface pathways become accessible while changing overall catchment storage. With surface mining, watersheds are altered such that they bare little resemblance to what existed prior to mining. In this presentation, data will be presented from long-term experiments exploring the impact of climate and mining on runoff processes in cold catchments using stable isotopes of water and associated hydrometric measurements. In southern Yukon, results from the Wolf Creek Research Basin highlights the influence of surface energy balances on controlling the timing and magnitude of flow response, with inter-annual variability largely driven by how atmospheric forcing interacts with permafrost-underlain areas of the catchment. In mountainous areas of southern British Columbia, surface mining reconfigures landscapes as valleys are filled with waste-rock. Mine-influenced catchments exhibit attenuated flows with delays in spring freshet and a more muted to precipitation. Stable isotopes in stream water suggests that both waste-rock and reference catchments are well mixed, however reference catchments are more responsive to enrichment and depletion events and that mine-influenced catchments had a heavier isotope signature than reference watersheds, suggesting enhanced influence of rainfall on recharge. In both cases, snow storage and release exerts considerable control on streamflow responses, and future changes in streamflow regimes will reflect both a changes in the snow

  17. Phenotype- and genotype-specific structural alterations in spasmodic dysphonia.

    Science.gov (United States)

    Bianchi, Serena; Battistella, Giovanni; Huddleston, Hailey; Scharf, Rebecca; Fleysher, Lazar; Rumbach, Anna F; Frucht, Steven J; Blitzer, Andrew; Ozelius, Laurie J; Simonyan, Kristina

    2017-04-01

    Spasmodic dysphonia is a focal dystonia characterized by involuntary spasms in the laryngeal muscles that occur selectively during speaking. Although hereditary trends have been reported in up to 16% of patients, the causative etiology of spasmodic dysphonia is unclear, and the influences of various phenotypes and genotypes on disorder pathophysiology are poorly understood. In this study, we examined structural alterations in cortical gray matter and white matter integrity in relationship to different phenotypes and putative genotypes of spasmodic dysphonia to elucidate the structural component of its complex pathophysiology. Eighty-nine patients with spasmodic dysphonia underwent high-resolution magnetic resonance imaging and diffusion-weighted imaging to examine cortical thickness and white matter fractional anisotropy in adductor versus abductor forms (distinct phenotypes) and in sporadic versus familial cases (distinct genotypes). Phenotype-specific abnormalities were localized in the left sensorimotor cortex and angular gyrus and the white matter bundle of the right superior corona radiata. Genotype-specific alterations were found in the left superior temporal gyrus, supplementary motor area, and the arcuate portion of the left superior longitudinal fasciculus. Our findings suggest that phenotypic differences in spasmodic dysphonia arise at the level of the primary and associative areas of motor control, whereas genotype-related pathophysiological mechanisms may be associated with dysfunction of regions regulating phonological and sensory processing. Identification of structural alterations specific to disorder phenotype and putative genotype provides an important step toward future delineation of imaging markers and potential targets for novel therapeutic interventions for spasmodic dysphonia. © 2017 International Parkinson and Movement Disorder Society. © 2017 International Parkinson and Movement Disorder Society.

  18. Alteration geochemistry of the volcanic-hosted Dedeninyurdu, Yergen and Fındıklıyar Fe-Cu mineralization at Gökçedoǧan, Çorum-Kargi region, Turkey

    Science.gov (United States)

    Gumus, Lokman; Öztürk, Sercan; Yalçın, Cihan; Abdelnasser, Amr; Hanilçi, Nurullah; Kumral, Mustafa

    2016-04-01

    This study is to determine the mass/volume gain and loss of the major and trace elements during the alteration processes on Dedeninyurdu, Yergen and Fındıklıyar Fe-Cu mineralizations of the area. Fe-Cu mineralization occurred in the spilitic volcanic a rock of Saraycık Formation is associated with the different types of alteration zones which are pyritization, silicification and sericitization. The study area comprises Bekirli Formation, Saraycık Formation, Beşpınar Formation, and Ilgaz Formation. Saraycık formation consists of spilitic volcanic rocks with pelagic limestone, siltstone and chert. The ore mineralogical data show that the pyrite, chalcopyrite, covellite, hematite, malachite and goethite formed during three phases of mineralization. As well as the geologic and petrographic studies reveal three alteration zones with definite mineral assemblages; phyllic alteration (quartz + sericite + pyrite) that represents the main alteration and mineralized zone; propylitic alteration; and carbonatized sericitic alteration zone. The boundaries between these zones are gradual. Mass balance calculations suggested that the phyllic alteration zone represented by gain in Si, Fe, K, S, and LOI and loss in Mg, Ca, and Na refers to silicification, sericitization and pyritization as well as replacement of Fe-Mg silicate and plagioclase. While, in the propylitic alteration zone, enrichment of Si, Fe, Mg, LOI and S occurred with depletions of Ca, Na, and K reflecting chloritization alteration type. On the other hand, carbonatized sericitic alteration zone shows local gain in Si, CaO and K reflects the occurrence of calc-silicate alteration. All alteration zones contain a large proportion of sulfide minerals (gain in S) with increase in loss on ignition (LOI). Keywords: Alteration geochemistry; Mass balance calculation, Fe-Cu mineralization; phyllic alteration, propylitic alteration.

  19. Viral haemorrhagic fever and vascular alterations.

    Science.gov (United States)

    Aleksandrowicz, P; Wolf, K; Falzarano, D; Feldmann, H; Seebach, J; Schnittler, H

    2008-02-01

    Pathogenesis of viral haemorrhagic fever (VHF) is closely associated with alterations of the vascular system. Among the virus families causing VHF, filoviruses (Marburg and Ebola) are the most fatal, and will be focused on here. After entering the body, Ebola primarily targets monocytes/macrophages and dendritic cells. Infected dendritic cells are largely impaired in their activation potency, likely contributing to the immune suppression that occurs during filovirus infection. Monocytes/macrophages, however, immediately activate after viral contact and release reasonable amounts of cytokines that target the vascular system, particularly the endothelial cells. Some underlying molecular mechanisms such as alteration of the vascular endothelial cadherin/catenin complex, tyrosine phosphorylation, expression of cell adhesion molecules, tissue factor and the effect of soluble viral proteins released from infected cells to the blood stream will be discussed.

  20. Alteration of sodium, potassium-adenosine triphosphatase activity in rabbit ciliary processes by cyclic adenosine monophosphate-dependent protein kinase

    International Nuclear Information System (INIS)

    Delamere, N.A.; Socci, R.R.; King, K.L.

    1990-01-01

    The response of sodium, potassium-adenosine triphosphatase (Na,K-ATPase) to cyclic adenosine monophosphate (cAMP)-dependent protein kinase was examined in membranes obtained from rabbit iris-ciliary body. In the presence of the protein kinase together with 10(-5) M cAMP, Na,K-ATPase activity was reduced. No change in Na,K-ATPase activity was detected in response to the protein kinase without added cAMP. Likewise cAMP alone did not alter Na,K-ATPase activity. Reduction of Na,K-ATPase activity was also observed in the presence of the cAMP-dependent protein kinase catalytic subunit. The response of the enzyme to the kinase catalytic subunit was also examined in membranes obtained from rabbit ciliary processes. In the presence of 8 micrograms/ml of the catalytic subunit, ciliary process Na,K-ATPase activity was reduced by more than 50%. To examine whether other ATPases were suppressed by the protein kinase, calcium-stimulated ATPase activity was examined; its activity was stimulated by the catalytic subunit. To test whether the response of the ciliary process Na,K-ATPase is unique, experiments were also performed using membrane preparations from rabbit lens epithelium or rabbit kidney; the catalytic subunit significantly reduced the activity of Na,K-ATPase from the kidney but not the lens. These Na,K-ATPase studies suggest that in the iris-ciliary body, cAMP may alter sodium pump activity. In parallel 86Rb uptake studies, we observed that ouabain-inhibitable potassium uptake by intact pieces of iris-ciliary body was reduced by exogenous dibutryl cAMP or by forskolin

  1. The Geology And Geochemistry Of Zona Uranium Occurence, Upper Benue Trough; N.E. Nigeria

    International Nuclear Information System (INIS)

    Ogunleye, P.O.; Okujeni, C.D.

    1993-01-01

    The Zona uranium is located at the NE flank of the Peta syncline, which is an arm of the Middle Gongola Basin. The hostreok- the Cretaceous Bima sandstone bears the imprint of more than two preore tectonic episodes which are thought to have resulted from reactivation of paleolineaments in the basement since the Pan African Orogeny. The mineralized zone occurs at point of intersection of a set of NE-SW trending shear zone and N-S fracture system. The centre of the ore zone exhibits intense alteration features such as sericitization, ferruginization, silification, remobilization and powdering of the rock matrix. These alteration features diminish progressively from the core to the periphery of the ore zone. The main uraniferous minerals identified are phosphouranylite and meta-autunite. These occur mainly absorbed to iron oxides, in silicified veinlets and partly disseminated in the matrix of the sandstone. Evaluation of the analytical data of 9 elements in 67 rock samples suggest a close link between ferruginization and enrichment of uranium. A model involving the leaching of the uranium from conceal volcanics (rhyolites) and granites at depths by heated groundwater residual magmatic solutions is proposed

  2. The Geology And Geochemistry Of Zona Uranium Occurence, Upper Benue Trough; N.E. Nigeria.

    Energy Technology Data Exchange (ETDEWEB)

    Ogunleye, P O [Centre For Energy Research And Training, Ahmadu Bello University, Zaria (Nigeria); Okujeni, C D [Department Of Geology, Ahmadu Bello University, Zaria (Nigeria)

    1994-12-31

    The Zona uranium is located at the NE flank of the Peta syncline, which is an arm of the Middle Gongola Basin. The hostreok- the Cretaceous Bima sandstone bears the imprint of more than two preore tectonic episodes which are thought to have resulted from reactivation of paleolineaments in the basement since the Pan African Orogeny. The mineralized zone occurs at point of intersection of a set of NE-SW trending shear zone and N-S fracture system. The centre of the ore zone exhibits intense alteration features such as sericitization, ferruginization, silification, remobilization and powdering of the rock matrix. These alteration features diminish progressively from the core to the periphery of the ore zone. The main uraniferous minerals identified are phosphouranylite and meta-autunite. These occur mainly absorbed to iron oxides, in silicified veinlets and partly disseminated in the matrix of the sandstone. Evaluation of the analytical data of 9 elements in 67 rock samples suggest a close link between ferruginization and enrichment of uranium. A model involving the leaching of the uranium from conceal volcanics (rhyolites) and granites at depths by heated groundwater residual magmatic solutions is proposed.

  3. Early maladaptive schema-related impairment and co-occurring current major depressive episode-related enhancement of mental state decoding ability in borderline personality disorder.

    Science.gov (United States)

    Unoka, Zsolt Szabolcs; Fogd, Dóra; Seres, Imola; Kéri, Szabolcs; Csukly, Gábor

    2015-04-01

    Disturbed interpersonal relationships specific to borderline personality disorder (BPD) suggest biased processing of social information. The goal of this study was to examine alterations in mental state decoding (MSD) and their associations with early maladaptive schemas (EMS) that may lead to the misinterpretation of incoming information. In addition, the authors' aim was to evaluate the effects of a co-occurring current major depressive episode (MDE) on the MSD performance of BPD patients. Seventy-eight BPD patients (34 with MDE) and 76 matched healthy controls (HC) were assessed for Reading the Mind in the Eyes Test (RMET) and the level of EMS. The authors found that impairment in the total RMET performance, as well as specific impairment regarding the recognition of positive and neutral items, was associated with EMS, and enhanced vigilance to negative mental states was characteristic to BPD with MDE. Results suggest that MSD ability is altered in two independent ways in BPD.

  4. Alteration of immature sedimentary rocks on Earth and Mars. Recording Aqueous and Surface-atmosphere Processes

    Energy Technology Data Exchange (ETDEWEB)

    Cannon, Kenneth M. [Brown Univ., Providence, RI (United States); Mustard, John F. [Brown Univ., Providence, RI (United States); Salvatore, Mark R. [Arizona State Univ., Mesa, AZ (United States)

    2015-03-05

    The rock alteration and rind formation in analog environments like Antarctica may provide clues to rock alteration and therefore paleoclimates on Mars. Clastic sedimentary rocks derived from basaltic sources have been studied in situ by martian rovers and are likely abundant on the surface of Mars. Moreover, how such rock types undergo alteration when exposed to different environmental conditions is poorly understood compared with alteration of intact basaltic flows. Here we characterize alteration in the chemically immature Carapace Sandstone from Antarctica, a terrestrial analog for martian sedimentary rocks. We employ a variety of measurements similar to those used on previous and current Mars missions. Laboratory techniques included bulk chemistry, powder X-ray diffraction (XRD), hyperspectral imaging and X-ray absorption spectroscopy. Through these methods we find that primary basaltic material in the Carapace Sandstone is pervasively altered to hydrated clay minerals and palagonite as a result of water–rock interaction. A thick orange rind is forming in current Antarctic conditions, superimposing this previous aqueous alteration signature. The rind exhibits a higher reflectance at visible-near infrared wavelengths than the rock interior, with an enhanced ferric absorption edge likely due to an increase in Fe3+ of existing phases or the formation of minor iron (oxy)hydroxides. This alteration sequence in the Carapace Sandstone results from decreased water–rock interaction over time, and weathering in a cold, dry environment, mimicking a similar transition early in martian history. This transition may be recorded in sedimentary rocks on Mars through a similar superimposition mechanism, capturing past climate changes at the hand sample scale. These results also suggest that basalt-derived sediments could have sourced significant volumes of hydrated minerals on early Mars due to their greater permeability compared with intact igneous rocks.

  5. Nitrogen soil emissions and belowground plant processes in Mediterranean annual pastures are altered by ozone exposure and N-inputs

    Science.gov (United States)

    Sánchez-Martín, L.; Bermejo-Bermejo, V.; García-Torres, L.; Alonso, R.; de la Cruz, A.; Calvete-Sogo, H.; Vallejo, A.

    2017-09-01

    Increasing tropospheric ozone (O3) and atmospheric nitrogen (N) deposition alter the structure and composition of pastures. These changes could affect N and C compounds in the soil that in turn can influence soil microbial activity and processes involved in the emission of N oxides, methane (CH4) and carbon dioxide (CO2), but these effects have been scarcely studied. Through an open top chamber (OTC) field experiment, the combined effects of both pollutants on soil gas emissions from an annual experimental Mediterranean community were assessed. Four O3 treatments and three different N input levels were considered. Fluxes of nitric (NO) and nitrous (N2O) oxide, CH4 and CO2 were analysed as well as soil mineral N and dissolved organic carbon. Belowground plant parameters like root biomass and root C and N content were also sampled. Ozone strongly increased soil N2O emissions, doubling the cumulative emission through the growing cycle in the highest O3 treatment, while N-inputs enhanced more slightly NO; CH4 and CO2 where not affected. Both N-gases had a clear seasonality, peaking at the start and at the end of the season when pasture physiological activity is minimal; thus, higher microorganism activity occurred when pasture had a low nutrient demand. The O3-induced peak of N2O under low N availability at the end of the growing season was counterbalanced by the high N inputs. These effects were related to the O3 x N significant interaction found for the root-N content in the grass and the enhanced senescence of the community. Results indicate the importance of the belowground processes, where competition between plants and microorganisms for the available soil N is a key factor, for understanding the ecosystem responses to O3 and N.

  6. Geophysical methods for monitoring soil stabilization processes

    Science.gov (United States)

    Saneiyan, Sina; Ntarlagiannis, Dimitrios; Werkema, D. Dale; Ustra, Andréa

    2018-01-01

    Soil stabilization involves methods used to turn unconsolidated and unstable soil into a stiffer, consolidated medium that could support engineered structures, alter permeability, change subsurface flow, or immobilize contamination through mineral precipitation. Among the variety of available methods carbonate precipitation is a very promising one, especially when it is being induced through common soil borne microbes (MICP - microbial induced carbonate precipitation). Such microbial mediated precipitation has the added benefit of not harming the environment as other methods can be environmentally detrimental. Carbonate precipitation, typically in the form of calcite, is a naturally occurring process that can be manipulated to deliver the expected soil strengthening results or permeability changes. This study investigates the ability of spectral induced polarization and shear-wave velocity for monitoring calcite driven soil strengthening processes. The results support the use of these geophysical methods as soil strengthening characterization and long term monitoring tools, which is a requirement for viable soil stabilization projects. Both tested methods are sensitive to calcite precipitation, with SIP offering additional information related to long term stability of precipitated carbonate. Carbonate precipitation has been confirmed with direct methods, such as direct sampling and scanning electron microscopy (SEM). This study advances our understanding of soil strengthening processes and permeability alterations, and is a crucial step for the use of geophysical methods as monitoring tools in microbial induced soil alterations through carbonate precipitation.

  7. Sulphur depletion altered somatic embryogenesis in Theobroma ...

    African Journals Online (AJOL)

    USER

    2010-08-30

    Aug 30, 2010 ... embryo) occur in response to alteration of genes expression patterns ... the proteins synthesis and the rate with which all amino ... thiamine-HCl, 1 mgml-1 nicotinic acid and 2 mgml-1 glycine), 20 gL-1 ... Amino acids and soluble sugar extraction .... 0.1% (v/v) Triton X-100, 0.1 % (w/v) dithiothreitol, and 0.2%.

  8. Raman and X-ray absorption spectroscopic studies of hydrothermally altered alkali-borosilicate nuclear waste glass

    Energy Technology Data Exchange (ETDEWEB)

    McKeown, David A., E-mail: davidm@vsl.cua.ed [Vitreous State Laboratory, Catholic University of America, 620 Michigan Ave., N.E., Washington, DC 20064 (United States); Buechele, Andrew C.; Viragh, Carol; Pegg, Ian L. [Vitreous State Laboratory, Catholic University of America, 620 Michigan Ave., N.E., Washington, DC 20064 (United States)

    2010-04-01

    Raman spectroscopy and X-ray absorption spectroscopy (XAS) are used to characterize structural changes that took place in hydrothermally altered (Na,K)-alumina-borosilicate glasses with different Na/K ratios, formulated as part of a durability study to investigate the behavior of glasses for nuclear waste storage. The hydrothermal experiments, or vapor hydration tests (VHT), were performed on each glass for 3 and 20 days at 200 deg. C to accelerate and approximate long-term alteration processes that may occur in a nuclear waste repository. Results found for both glasses and their VHT altered counterparts show little, if any, structural influence from the different starting Na/K ratios. X-ray diffraction, differential scanning calorimetry, scanning electron microscopy, and Raman spectroscopy indicate that the altered samples are mostly amorphous with small amounts of analcime-like and leucite-like crystals within 200 mum of the sample surface and contain up to 9.7 wt.% water or OH. The Raman data are nearly identical for the amorphous portions of all altered VHT samples investigated, and indicate that two glass structural changes took place during alteration: one, partial depolymerization of the alumina-borosilicate network, and two, introduction of water or OH. Al and Si XAS data indicate tetrahedral AlO{sub 4} and SiO{sub 4} environments in the original glasses as well as in the altered samples. Small energy shifts of the Si K-edge also show that the altered VHT samples have less polymerized networks than the original glass. Na XAS data indicate expanded Na environments in the VHT samples with longer Na-O distances and more nearest-neighbor oxygen atoms, compared with the original glasses, which may be due to hydrous species introduced into the expanding Na-sites.

  9. Partial sleep deprivation does not alter processes involved in semantic word priming: event-related potential evidence.

    Science.gov (United States)

    Tavakoli, Paniz; Muller-Gass, Alexandra; Campbell, Kenneth

    2015-03-01

    Sleep deprivation has generally been observed to have a detrimental effect on tasks that require sustained attention for successful performance. It might however be possible to counter these effects by altering cognitive strategies. A recent semantic word priming study indicated that subjects used an effortful predictive-expectancy search of semantic memory following normal sleep, but changed to an automatic, effortless strategy following total sleep deprivation. Partial sleep deprivation occurs much more frequently than total sleep deprivation. The present study therefore employed a similar priming task following either 4h of sleep or following normal sleep. The purpose of the study was to determine whether partial sleep deprivation would also lead to a shift in cognitive strategy to compensate for an inability to sustain attention and effortful processing necessary for using the predicative expectancy strategy. Sixteen subjects were presented with word pairs, a prime and a target that were either strongly semantically associated (cat...dog), weakly associated (cow...barn) or not associated (apple...road). The subject's task was to determine if the target word was semantically associated to the prime. A strong priming effect was observed in both conditions. RTs were slower, accuracy lower, and N400 larger to unassociated targets, independent of the amount of sleep. The overall N400 did not differ as a function of sleep. The scalp distribution of the N400 was also similar following both normal sleep and sleep loss. There was thus little evidence of a difference in the processing of the target stimulus as a function of the amount sleep. Similarly, ERPs in the period between the onset of the prime and the subsequent target also did not differ between the normal sleep and sleep loss conditions. In contrast to total sleep deprivation, subjects therefore appeared to use a common predictive expectancy strategy in both conditions. This strategy does however require an

  10. Experience acquired over a four-year period using Vichi's scoring system in chest alterations occurring in patients with cystic fibrosis

    International Nuclear Information System (INIS)

    Vichi, G.F.; Jenuso, R.; Pellegrini, T.

    1987-01-01

    The classification of chest alterations in Cystic Fibrosis (CF) and related score proposed by Chrispin and Norman has been widely adopted in Europe and is still applied (although slightly modified) in most European Centres. Brasfield classification instead has been monstly used in the USA. Lately, however, to revise both classifications, the need has been felt, for a more precise correlation to anatomo-radiological data as well as for inclusion of headings which have not been taken into account so far. In 1980 one of the authors (Vichi) worked out a new scoring system for the chest alterations of CF. Results are reported from a follow-up of 15 patients with CF carried out at the FC Center of Meyer Ospedale in Florence from the late 1981 to 1985. The patients underwent periodic checking including determination of clinical scoring system-according to Shwachman and Kulczychi modified by Doershuk-respiratory function tests, chest X-rays evaluated by three radiologists separately, following both Chrispin and Norman and Vichi scoring systems. The latter system has proved to be well correlated to clinical data and to the ordinary pulmonary function tests but it mainly presents a high observer reproducibility

  11. Alterations in white matter pathways underlying phonological and morphological processing in Chinese developmental dyslexia

    Directory of Open Access Journals (Sweden)

    Mengmeng Su

    2018-06-01

    Full Text Available Chinese is a logographic language that is different from alphabetic languages in visual and semantic complexity. Thus far, it is still unclear whether Chinese children with dyslexia show similar disruption of white matter pathways as in alphabetic languages. The present study focused on the alteration of white matter pathways in Chinese children with dyslexia. Using diffusion tensor imaging tractography, the bilateral arcuate fasciculus (AF-anterior, AF-posterior and AF-direct segments, inferior fronto-occipital fasciculus (IFOF and inferior longitudinal fasciculus (ILF were delineated in each individual’s native space. Compared with age-matched controls, Chinese children with dyslexia showed reduced fractional anisotropy in the left AF-direct and the left ILF. Further regression analyses revealed a functional dissociation between the left AF-direct and the left ILF. The AF-direct tract integrity was associated with phonological processing skill, an ability important for reading in all writing systems, while the ILF integrity was associated with morphological processing skill, an ability more strongly recruited for Chinese reading. In conclusion, the double disruption locus in Chinese children with dyslexia, and the functional dissociation between dorsal and ventral pathways reflect both universal and specific properties of reading in Chinese.

  12. Iron isotope fractionation during hydrothermal ore deposition and alteration

    Science.gov (United States)

    Markl, Gregor; von Blanckenburg, Friedhelm; Wagner, Thomas

    2006-06-01

    Iron isotopes fractionate during hydrothermal processes. Therefore, the Fe isotope composition of ore-forming minerals characterizes either iron sources or fluid histories. The former potentially serves to distinguish between sedimentary, magmatic or metamorphic iron sources, and the latter allows the reconstruction of precipitation and redox processes. These processes take place during ore formation or alteration. The aim of this contribution is to investigate the suitability of this new isotope method as a probe of ore-related processes. For this purpose 51 samples of iron ores and iron mineral separates from the Schwarzwald region, southwest Germany, were analyzed for their iron isotope composition using multicollector ICP-MS. Further, the ore-forming and ore-altering processes were quantitatively modeled using reaction path calculations. The Schwarzwald mining district hosts mineralizations that formed discontinuously over almost 300 Ma of hydrothermal activity. Primary hematite, siderite and sulfides formed from mixing of meteoric fluids with deeper crustal brines. Later, these minerals were partly dissolved and oxidized, and secondary hematite, goethite and iron arsenates were precipitated. Two types of alteration products formed: (1) primary and high-temperature secondary Fe minerals formed between 120 and 300 °C, and (2) low-temperature secondary Fe minerals formed under supergene conditions (illustrates the potential of the new technique in deciphering ore formation and alteration processes. Isotope ratios are strongly dependent on and highly characteristic of fluid and precipitation histories. Therefore, they are less suitable to provide information on Fe sources. However, it will be possible to unravel the physico-chemical processes leading to the formation, dissolution and redeposition of ores in great detail.

  13. Altered nutrition during hot droughts will impair forest functions in the future

    Science.gov (United States)

    Grossiord, C.; Gessler, A.; Reed, S.; Dickman, L. T.; Collins, A.; Schönbeck, L.; Sevanto, S.; Vilagrosa, A.; McDowell, N. G.

    2017-12-01

    Rising greenhouse gas emissions will increase atmospheric temperature globally and alter hydrological cycles resulting in more extreme and recurrent droughts in the coming century. Nutrition is a key component affecting the vulnerability of forests to extreme climate. Models typically assume that global warming will enhance nitrogen cycling in terrestrial ecosystems and lead to improved plant functions. Drought on the other hand is expected to weaken the same processes, leading to a clear conflict and inability to predict how nutrition and plant functions will be impacted by a simultaneously warming and drying climate. We used a unique setup consisting of long-term manipulation of climate on mature trees to examine how individual vs. combined warming and drought would alter soil N cycling and tree functions. The site consists of the longest record of tree responses to experimental warming and precipitation reduction in natural conditions.Changes in soil nitrogen cycling (e.g. microbial activity, nitrification and ammonification rates, N concentration) occurred in response to the treatments. In addition, temperature rise and precipitation reduction altered the ability of trees to take up nitrogen and modified nitrogen allocation patterns between aboveground and belowground compartments. Although no additive effect of warming and drying were found for the two studied species, contrasting responses to warming and droughts were observed between the two functional types. Overall, our results show that higher temperature and reduced precipitation will alter the nutrition of forest ecosystems in the future with potentially large consequences for forest functions, structure and biodiversity.

  14. The study of hydrothermal alteration zones in Kahang exploration area (north eastern of Isfahan, central of Iran) using microscopy studies and TM and Aster satellite data

    Science.gov (United States)

    Zahra Afshooni, Seyedeh; Esmaeily, Dariush

    2010-05-01

    Kahang ore deposit located in 73 km to the northeast of Isfahan city and 10 km to the east of Zefreh town, covering an area about 18.6 km2. This ore deposit is a part of Uromieh-Dokhtar volcanopolotonic belt. The rocks of the area included Andesite, Porphyritic Andesite, Dacite, Porphyritic, Rhyodacite, Diorite, Quartz Monzonite and Porphyry Micro Granite. In plutons, there is a trend from basic to acid features along with decreasing of age from margin to center of massive. Kahang region is an alteration and breccia zone. The occurrence of alteration zones and iron oxides were confirmed by satellite images processing. Generally, more than 90% of rocks of this region have been affected by hydrothermal fluids. Remote sensing refers to detection and measurement from a distance. For the first time, this exploration area was studied using satellite images processing (TM) and primary results showed that is suitable place for resources of Copper (Cu) and Molybdenum (Mo). Hydrothermal alteration commonly occurs in geothermal areas in association with ore deposits producing alteration assemblages typically dominated by silicates, sulfides, sulfates and carbonates. In the alteration zones studies the subject discussed is the study of existing minerals in such zones and study of chemical specifications of altering fluids. Four alteration zones Based on observations derived from the study of thin sections, XRD analysis and deep remote sensing using TM and Aster satellite images studies could be identified in this area: propylitic alteration zone with chlorite, epidot, calcite; argillic alteration zone with clay minerals; phyllic (qartz-sericite) alteration zone with quartz, sericite and pyrite and silicic alteration zone with abundant quartz.

  15. [Epigenetic alterations in acute lymphoblastic leukemia].

    Science.gov (United States)

    Navarrete-Meneses, María Del Pilar; Pérez-Vera, Patricia

    Acute lymphoblastic leukemia (ALL) is the most common childhood cancer. It is well-known that genetic alterations constitute the basis for the etiology of ALL. However, genetic abnormalities are not enough for the complete development of the disease, and additional alterations such as epigenetic modifications are required. Such alterations, like DNA methylation, histone modifications, and noncoding RNA regulation have been identified in ALL. DNA hypermethylation in promoter regions is one of the most frequent epigenetic modifications observed in ALL. This modification frequently leads to gene silencing in tumor suppressor genes, and in consequence, contributes to leukemogenesis. Alterations in histone remodeling proteins have also been detected in ALL, such as the overexpression of histone deacetylases enzymes, and alteration of acetyltransferases and methyltransferases. ALL also shows alteration in the expression of miRNAs, and in consequence, the modification in the expression of their target genes. All of these epigenetic modifications are key events in the malignant transformation since they lead to the deregulation of oncogenes as BLK, WNT5B and WISP1, and tumor suppressors such as FHIT, CDKN2A, CDKN2B, and TP53, which alter fundamental cellular processes and potentially lead to the development of ALL. Both genetic and epigenetic alterations contribute to the development and evolution of ALL. Copyright © 2017 Hospital Infantil de México Federico Gómez. Publicado por Masson Doyma México S.A. All rights reserved.

  16. Evaluation of bentonite alteration due to interactions with iron. Sensitivity analyses to identify the important factors for the bentonite alteration

    International Nuclear Information System (INIS)

    Sasamoto, Hiroshi; Wilson, James; Sato, Tsutomu

    2013-01-01

    Performance assessment of geological disposal systems for high-level radioactive waste requires a consideration of long-term systems behaviour. It is possible that the alteration of swelling clay present in bentonite buffers might have an impact on buffer functions. In the present study, iron (as a candidate overpack material)-bentonite (I-B) interactions were evaluated as the main buffer alteration scenario. Existing knowledge on alteration of bentonite during I-B interactions was first reviewed, then the evaluation methodology was developed considering modeling techniques previously used overseas. A conceptual model for smectite alteration during I-B interactions was produced. The following reactions and processes were selected: 1) release of Fe 2+ due to overpack corrosion; 2) diffusion of Fe 2+ in compacted bentonite; 3) sorption of Fe 2+ on smectite edge and ion exchange in interlayers; 4) dissolution of primary phases and formation of alteration products. Sensitivity analyses were performed to identify the most important factors for the alteration of bentonite by I-B interactions. (author)

  17. Altered Cortical Swallowing Processing in Patients with Functional Dysphagia: A Preliminary Study

    Science.gov (United States)

    Wollbrink, Andreas; Warnecke, Tobias; Winkels, Martin; Pantev, Christo; Dziewas, Rainer

    2014-01-01

    Objective Current neuroimaging research on functional disturbances provides growing evidence for objective neuronal correlates of allegedly psychogenic symptoms, thereby shifting the disease concept from a psychological towards a neurobiological model. Functional dysphagia is such a rare condition, whose pathogenetic mechanism is largely unknown. In the absence of any organic reason for a patient's persistent swallowing complaints, sensorimotor processing abnormalities involving central neural pathways constitute a potential etiology. Methods In this pilot study we measured cortical swallow-related activation in 5 patients diagnosed with functional dysphagia and a matched group of healthy subjects applying magnetoencephalography. Source localization of cortical activation was done with synthetic aperture magnetometry. To test for significant differences in cortical swallowing processing between groups, a non-parametric permutation test was afterwards performed on individual source localization maps. Results Swallowing task performance was comparable between groups. In relation to control subjects, in whom activation was symmetrically distributed in rostro-medial parts of the sensorimotor cortices of both hemispheres, patients showed prominent activation of the right insula, dorsolateral prefrontal cortex and lateral premotor, motor as well as inferolateral parietal cortex. Furthermore, activation was markedly reduced in the left medial primary sensory cortex as well as right medial sensorimotor cortex and adjacent supplementary motor area (pdysphagia - a condition with assumed normal brain function - seems to be associated with distinctive changes of the swallow-related cortical activation pattern. Alterations may reflect exaggerated activation of a widely distributed vigilance, self-monitoring and salience rating network that interferes with down-stream deglutition sensorimotor control. PMID:24586948

  18. Alterations in Helicobacter pylori triggered by contact with gastric epithelial cells

    Directory of Open Access Journals (Sweden)

    Elizabeth M. Johnson

    2012-02-01

    Full Text Available Helicobacter pylori lives within the mucus layer of the human stomach, in close proximity to gastric epithelial cells. While a great deal is known about the effects of H. pylori on human cells and the specific bacterial products that mediate these effects, relatively little work has been done to investigate alterations in H. pylori that may be triggered by bacterial contact with human cells. In this review, we discuss the spectrum of changes in bacterial physiology and morphology that occur when H. pylori is in contact with gastric epithelial cells. Several studies have reported that cell contact causes alterations in H. pylori gene transcription. In addition, H. pylori contact with gastric epithelial cells promotes the formation of pilus-like structures at the bacteria-host cell interface. The formation of these structures requires multiple genes in the cag pathogenicity island, and these structures are proposed to have an important role in the type IV secretion system-dependent process through which CagA enters host cells. Finally, H. pylori contact with epithelial cells can promote bacterial replication and the formation of microcolonies, phenomena that are facilitated by the acquisition of iron and other nutrients from infected cells. In summary, the gastric epithelial cell surface represents an important niche for H. pylori, and upon entry into this niche, the bacteria alter their behavior in a manner that optimizes bacterial proliferation and persistent colonization of the host.

  19. Investigation of the environmental impacts of naturally occurring radionuclides in the processing of sulfide ores for gold using gamma spectrometry

    International Nuclear Information System (INIS)

    Gbadago, J K; Darko, E O; Faanhof, A; Schandorf, C

    2011-01-01

    The possible environmental impacts of naturally occurring radionuclides on workers and a critical community, as a result of milling and processing sulfide ores for gold by a mining company at Bogoso in the western region of Ghana, have been investigated using gamma spectroscopy. Indicative doses for the workers during sulfide ore processing were calculated from the activity concentrations measured at both physical and chemical processing stages. The dose rate, annual effective dose equivalent, radium equivalent activity, external and internal hazard indices, and radioactivity level index for tailings, for the de-silted sediments of run-off from the vicinity of the tailings dam through the critical community, and for the soils of the critical community's basic schools were calculated and found to be lower than their respective permissible limits. The environmental impact of the radionuclides is therefore expected to be low in this mining environment.

  20. Investigation of the environmental impacts of naturally occurring radionuclides in the processing of sulfide ores for gold using gamma spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Gbadago, J K; Darko, E O [Ghana Atomic Energy Commission, PO Box LG 80, Legon, Accra (Ghana); Faanhof, A [South African Nuclear Energy Corporation, PO Box 582, Pretoria 0001 (South Africa); Schandorf, C, E-mail: jgbada@yahoo.com [School of Nuclear and Allied Sciences, University of Ghana, Legon, Accra (Ghana)

    2011-09-01

    The possible environmental impacts of naturally occurring radionuclides on workers and a critical community, as a result of milling and processing sulfide ores for gold by a mining company at Bogoso in the western region of Ghana, have been investigated using gamma spectroscopy. Indicative doses for the workers during sulfide ore processing were calculated from the activity concentrations measured at both physical and chemical processing stages. The dose rate, annual effective dose equivalent, radium equivalent activity, external and internal hazard indices, and radioactivity level index for tailings, for the de-silted sediments of run-off from the vicinity of the tailings dam through the critical community, and for the soils of the critical community's basic schools were calculated and found to be lower than their respective permissible limits. The environmental impact of the radionuclides is therefore expected to be low in this mining environment.

  1. Autoradiography in Studying the Alteration of Rocks; L'Autoradiographie dans l'Etude de l'Alteration des Roches

    Energy Technology Data Exchange (ETDEWEB)

    Leveque, P.; Vigneaux, M. [Institut de Geologie du Bassin d' Aquitaine, Faculte des Sciences de l' Universite de Bordeaux (France)

    1967-06-15

    The alteration of rocks intended for use as the foundations of large-scale civil-engineering projects, for building construction and for rock piling has been studied and numerous tests carried out; some of these tests have been standardized in varying degrees. The conventional method of autoradiography has been used to develop one of the processes for estimating alteration due, in particular, to thermal shocks. By using {sup 35}S and {sup 32}P, the authors were able to follow the progressive alteration of different rocks in the form of microfissurations. This process is considerably more accurate than that based solely on utilization of the characteristics of rocks in normal or polarized light. In addition, it permits absolute comparison of the initial microfissuration conditions of the sample and the microfissuration found after an increasing number of thermal shock cycles. The results of the process are given in the paper. (author) [French] L'alterabilite des roches destinees, soit a des fondations de grands travaux de genie civil, soit a la construction d'immeubles, soit enfin a l'etablissement d'enrochements, a fait l'objet de nombreux essais dont certains ont ete normalises, ou tout au moins ont subi un debut de normalisation. Un des procedes de determination du processus d'alteration du notamment aux chocs thermiques a ete mis au point a partir de la methode classique d'autoradiographie. L'utilisation de {sup 35}S et de {sup 32}P a permis de suivre la progression de l'alteration par microfissuration dans des roches diverses. Ce procede est notablement plus precis que celui qui est fonde sur la seule utilisation des caracteristiques des roches en lumiere naturelle ou polarisee. De plus, il permet la comparaison en valeur absolue de l'etat de microfissuration initial de l'echantillon avec la microfissuration obtenue apres un nombre croissant de cycles de chocs thermiques. Les resultats obtenus grace a ce procede sont donnes dans le memoire. (author)

  2. The role of post-ore processes in the alteration of infiltrational uranium deposits

    International Nuclear Information System (INIS)

    Kondrat'eva, I.A.; Bobrova, L.L.; Nesterova, M.V.

    1992-01-01

    Ore-bearing rocks and ores of uranium deposits that are associated with gray alluvial deposits and formed through oxidation of sedimentary beds at the end of the Jurassic, have undergone intensive alterations. The impact of hot carbonic acid solutions on infiltrational uranium deposits, along with calcite and hematite, resulted in partial dissolution of and redeposition of uranium. Uranium concentrates with newly formed Fe-bisulfides and hydroxides in the reducing stage of epigenetic alterations within a hydrochemical sulfide-gley medium, leading to changes in ore morphology. 20 refs., 7 figs., 3 tabs

  3. Can human activities alter the drowning fate of barrier islands?

    Science.gov (United States)

    Lorenzo-Trueba, J.; Ashton, A. D.; Jin, D.; Hoagland, P.; Kite-Powell, H.

    2012-12-01

    Low-lying coastal barriers face an uncertain future over the coming century and beyond as sea levels rise, with many projections suggesting end-of-century rates of sea-level rise as high or higher than 1 cm/yr. Geologically, such rates of sea-level rise have been experienced several thousand years ago and we can use our understanding of geological processes and sedimentary evidence to help unravel the dynamics of natural barriers experiencing sea-level rise. Along many modern coastal barriers, however, anthropic change, such as beach nourishment, dune construction, and emplacement of hard structures, plays a dominant role in coastline dynamics. A fundamental question to be addressed is whether human activities intended to preserve infrastructure and beach recreation may make wholesale collapse, or 'drowning,' of barrier systems more likely. Here we present a numerical modeling tool that couples natural processes and the human responses to these changes (and the subsequent of human responses on natural processes). Recent theoretical model development suggests that barriers are intrinsically morphodynamic features, responding to sea-level rise in complex ways through the interactions of marine processes and barrier overwash. Undeveloped coastal barriers would therefore respond to an accelerated sea-level rise in complex, less predictable manners than suggested by existing long-term models. We have developed a model that examines non-equilibrium cross-shore evolution of barrier systems at decadal to centennial temporal scales, focusing on the interactions between processes of shoreface evolution and overwash deposition. Model responses demonstrate two means of barrier collapse during sea-level rise: 'height drowning', which occurs when overwash fluxes are insufficient to maintain the landward migration rate required to keep in pace with sea-level rise, and 'width drowning', which occurs when the shoreface response is insufficient to maintain the barrier geometry

  4. Trauma-related altered states of consciousness in women with BPD with or without co-occurring PTSD

    Directory of Open Access Journals (Sweden)

    Paul Frewen

    2014-08-01

    Full Text Available Background: A “4-D model” was recently described as a theoretical framework for categorizing trauma-related symptoms into four phenomenological dimensions (the experience of time, thought, body, and emotion that can present either in the form of normal waking consciousness (NWC or as dissociative experiences, that is, trauma-related altered states of consciousness (TRASC. Methods: The present study examined the predictions of the 4-D model in 258 persons with borderline personality disorder (BPD with (n=126 versus without (n=132 posttraumatic stress disorder (PTSD. Results: As measured by the Borderline Symptom List, consistent with the predictions of the 4-D model, in comparison with symptom endorsements theorized to be associated with NWC, measures of TRASC were less frequent, and more strongly correlated with both Dissociative Experience Scale scores and severity of childhood emotional neglect, particularly in persons with both BPD and PTSD. Our prediction that symptoms of TRASC would be less intercorrelated in comparison with distress associated with NWC symptoms, however, was not supported. Conclusions: Findings are discussed as they pertain to the symptomatology of BPD, PTSD, and dissociation.

  5. Hydrothermal alteration in Dumoga Barat, Bolaang Mongondow area North Sulawesi

    International Nuclear Information System (INIS)

    Agus Harjanto' Sutanto; Sutarto; Achmad Subandrio; I Made Suasta; Juanito Salamat; Giri Hartono; Putu Suputra; I Gde Basten; Muhammad Fauzi; Rosdiana

    2016-01-01

    Bolaang Mongondow is located in central north Sulawesi arm, which is composed of Neogen magmatic arc and potentially contain economic minerals. This condition is behind the research purpose to study the mineral resources potencies. Research aim is to study alteration caused by hydrothermal process and its relation with gold (Au) deposit based on field study and laboratory analysis. Methodologies used for the research are literature study, geological survey, rocks sampling, laboratory analysis, and data processing. Research area is a multiply diorite intrusion complex. Andesite, volcaniclastic rocks, and dacite, the older rocks, were intruded by this complex. Later, dacitic tuff, volcanic sandstone, and alluvium deposited above them. There are three measured and mapped major faults heading NE-SW crossed by E-W fault and NW-SE fault lately crossed all the older faults. Early stage hydrothermal alteration related to the existence of young quartz diorite, showing alteration stage from the potassic center to distal prophylatic. Final stage hydrothermal alteration consist of argilic, advanced argilic, and silica-clay mineral±magnetite±chlorite alteration overlapping the earlier alteration. Mineralization of Cu-Au±Ag in central part of research area or Tayap-Kinomaligan area is mostly associated with potassic altered young quartz diorite and crossed by parallel and stock worked quartz-magnetite-chalcopyrite±bornite vein. (author)

  6. Phanerozoic extensional faulting and alteration control on uranium mineralization in trachytes of the Central Eastern Desert of Egypt

    Science.gov (United States)

    Hamdy, Mohamed M.; Waheeb, Anton G.; Aly, Samir M.; Farag, Nagdy M.; Sadek, Adel F.

    2017-12-01

    The Gabal Nasb El Atshan Upper Carboniferous-Lower Permian altered trachytes include uranium up to 3165 ppm. The paleostress and resolved shear stress analyses of the deformation systems in Gabal Nasb El Atshan area indicate that the trachyte was subjected to WNW-ESE to E-W tensile shear stress directed extensional regimes. The low-stress regions in the vicinity of extensional faults and their associated joints were favorable locations for fluid flow and the consequence alteration and U-mineralization. This occurred more extensively along the contacts between the sills of trachyte and the Hammamat sedimentary rocks; where the latter acted as a physical barrier for the alteration fluids migration outward. Alteration styles include albitization, aegirinization, arfvedsonization, chloritization and ferruginisation. The albitization is the most common sodic metasomatism, giving sanidine from Or98.8Ab0.7 to Or62.3Ab37.6, anorthoclase from Or51.4Ab48.0 to Or12.2Ab87.6 and albite from Or11.0Ab89.0 to Or0.8Ab99.2. Aegirine and arfvedsonite formed due to decreasing sodium activity in the metasomatic fluids. Sodic metasomatism may be the source of uranium-enrichment, taking place during the late magmatic to deuteric processes. This was followed by a retrograde alteration of chloritization between 175 and 42 °C toward precipitation of Fe-oxides and alteration of primary uranium. Surficial low-temperature alteration remobilized and redistributed the produced uranylhydroxides and ferruginisation caused the reduction and adsorption of U forming betafite, uranophane, soddyite, umohoite, uranotile and uranopilite.

  7. Histological and histochemical alterations in the kidney induced by lead

    International Nuclear Information System (INIS)

    Jarrar, Bashir M.

    2003-01-01

    Although lead intoxication is one of the most common forms of metal intoxication,the histochemichal alterations in renal tissues due to chronic lead exposure is limited and has not yet been well identified. A total of 60 male Wistar albino rats were exposed to lead acetate trihydrate( 0.0, 0.25, 0.5, 1.0 and 2% for 1 to 12 months) in drinking water to investigate the histological and histochemical alterations in renal tissues due to lead. Chronic exposure to the subtoxic doses of lead produced distinct progressive tubular, glomerular and interstitial damages. Tubular changes occured earlier than the glomerular and interstitial ones,and included anisokaryosis, nuclear pyknosis,karyomeglay, development of intranuclear cytoplasmic inclusions together with tubular dilation, necrosis,vacuolization, tubular hyperplasia and solid tubular adenoma. The glomrular alterations were mainly mesangial hypercellularity, segmental glomerulosclerosis, glomerular hyalinization and glomerular tuft alterations. The findings indicate that lead produces significant histological and histochemical changes in the kidney that lead to severe complications. (author)

  8. Laboratory simulated hydrothermal alteration of sedimentary organic matter from Guaymas Basin, Gulf of California. Ph.D. Thesis

    Science.gov (United States)

    Leif, Roald N.

    1993-01-01

    High temperature alteration of sedimentary organic matter associated with marine hydrothermal systems involves complex physical and chemical processes that are not easily measured in most natural systems. Many of these processes can be evaluated indirectly by examining the geochemistry of the hydrothermal system in the laboratory. In this investigation, an experimental organic geochemical approach to studying pyrolysis of sedimentary organic matter is applied to the hydrothermal system in the Guaymas Basin, Gulf of California. A general survey of hydrothermal oils and extractable organic matter (bitumen) in hydrothermally altered sediments identified several homologous series of alkanones associated with a high temperature hydrothermal origin. The alkanones range in carbon number from C11 to C30 with no carbon number preference. Alkan-2-ones are in highest concentrations, with lower amounts of 3-, 4-, 5- (and higher) homologs. The alkanones appear to be pyrolysis products synthesized under extreme hydrothermal conditions. Hydrous pyrolysis and confinement pyrolysis experiments were performed to simulate thermally enhanced diagenetic and catagenetic changes in the immature sedimentary organic matter. The extent of alteration was measured by monitoring the n-alkanes, acyclic isoprenoids, steroid and triterpenoid biomarkers, polycyclic aromatic hydrocarbons and alkanones. The results were compared to bitumen extracts from sediments which have been naturally altered by a sill intrusion and accompanied hydrothermal fluid flow. These pyrolysis experiments duplicated many of the organic matter transformations observed in the natural system. Full hopane and sterane maturation occurred after 48 hr in experiments at 330 deg C with low water/rock mass ratios (0.29). A variety of radical and ionic reactions are responsible for the organic compound conversions which occur under extreme hydrothermal conditions. Short duration pyrolysis experiments revealed that a portion of the

  9. Evolution of organic matter in Orgueil, Murchison and Renazzo during parent body aqueous alteration: In situ investigations

    Science.gov (United States)

    Le Guillou, Corentin; Bernard, Sylvain; Brearley, Adrian J.; Remusat, Laurent

    2014-04-01

    Chondrites accreted the oldest solid materials in the solar system including dust processed in the protoplanetary disk and diverse organic compounds. After accretion, asteroidal alteration may have impacted organic particles in various ways. To constrain these processes, we conducted a comprehensive study of organics disseminated within the matrices of the three carbonaceous chondrite falls, Renazzo (CR2), Murchison (CM2) and Orgueil (CI). By combining synchrotron-based STXM and TEM analyses on FIB sections of samples previously characterized by NanoSIMS, we investigated the influence of aqueous alteration on the morphology, isotopic signature, molecular structure, spatial distribution, and mineralogical environment of the organic matter within the matrices. Two different populations of materials are distinguishable: sub-micrometric individual grains, likely dominated by insoluble compounds and diffuse organic matter, finely interspersed within phyllosilicates and/or (amorphous) nanocarbonates at the nanometer scale. We suggest that this latter component, which is depleted in aromatics and enriched in carboxylic functional groups, may be dominated by soluble compounds. Organic matter in Renazzo (CR) mainly consists of chemically-homogeneous individual grains surrounded by amorphous and nanocrystalline phyllosilicates. Evidence of connectivity between organic grains and fractures indicates that redistribution has occurred: some areas containing diffuse organic matter can be observed. This diffuse organic component is more abundant in Murchison (CM) and Orgueil (CI). This is interpreted as resulting from fluid transport at the micrometer scale and encapsulation within recrystallized alteration phases. In contrast to Renazzo, organic grains in Murchison and Orgueil display strong chemical heterogeneities, likely related to chemical evolution during aqueous alteration. The observations suggest that the altering fluid was a brine with elevated concentrations of both

  10. Selective attention to affective value alters how the brain processes olfactory stimuli.

    Science.gov (United States)

    Rolls, Edmund T; Grabenhorst, Fabian; Margot, Christian; da Silva, Maria A A P; Velazco, Maria Ines

    2008-10-01

    How does selective attention to affect influence sensory processing? In a functional magnetic resonance imaging investigation, when subjects were instructed to remember and rate the pleasantness of a jasmine odor, activations were greater in the medial orbito-frontal and pregenual cingulate cortex than when subjects were instructed to remember and rate the intensity of the odor. When the subjects were instructed to remember and rate the intensity, activations were greater in the inferior frontal gyrus. These top-down effects occurred not only during odor delivery but started in a preparation period after the instruction before odor delivery, and continued after termination of the odor in a short-term memory period. Thus, depending on the context in which odors are presented and whether affect is relevant, the brain prepares itself, responds to, and remembers an odor differently. These findings show that when attention is paid to affective value, the brain systems engaged to prepare for, represent, and remember a sensory stimulus are different from those engaged when attention is directed to the physical properties of a stimulus such as its intensity. This differential biasing of brain regions engaged in processing a sensory stimulus depending on whether the cognitive demand is for affect-related versus more sensory-related processing may be an important aspect of cognition and attention. This has many implications for understanding the effects not only of olfactory but also of other sensory stimuli.

  11. Altered food cue processing in chronically ill and recovered women with Anorexia Nervosa.

    Directory of Open Access Journals (Sweden)

    Nicole eSanders

    2015-02-01

    Full Text Available Anorexia Nervosa (AN is a severe mental disorder characterized by food restriction and weight loss.This study aimed to test the model posed by Brooks et al. (2012, that women suffering from chronic AN show decreased food cue processing activity in brain regions associated with energy balance and food reward (bottom-up; BU and increased activity in brain regions associated with cognitive control (top-down; TD when compared to long term recovered AN (REC and healthy controls (HC. Three groups of women, 15 AN (mean illness duration 7.8 ± 4.1 y, 14 REC (mean duration of recovery 4.7 ± 2.7 yr and 15 HC viewed alternating blocks of food and non-food images preceded by a short instruction during functional magnetic resonance imaging (fMRI, after fasting overnight. Functional ROIs (fROIs were defined in BU (e.g. striatum, hippocampus, amygdala, hypothalamus and cerebellum, TD (e.g. medial and lateral prefrontal cortex, anterior cingulate, the insula and visual processing areas (VPA. Food-cue processing activation was extracted from all fROIs and compared between the groups. In addition, functional connectivity between the fROIs was examined by modular partitioning of the correlation matrix of all fROIs.We could not confirm the hypothesis that BU areas are activated to a lesser extent in AN upon visual processing of food images. Among the BU areas the caudate showed higher activation in both patient groups compared to HC. In accordance with Brooks et al.’s model, we did find evidence for increased TD control in AN and REC. The functional connectivity analysis yielded two clusters in HC and REC, but three clusters in AN. In HC fROIs across BU, TD and VPA areas clustered, in AN one cluster span across BU, TD and insula, one across BU, TD and VPA areas and one was confined to the VPA network. In REC BU, TD and VPA or VPA and insula clustered.In conclusion, despite weight recovery, neural processing of food cues is also altered in recovered AN patient

  12. Meteoric water alteration of soil and landscapes at Meridiani Planum, Mars

    Science.gov (United States)

    Amundson, Ronald

    2018-04-01

    The geomorphology and geochemistry data gathered by the MER Opportunity at Meridiani Planum is a rich data set relevant to soil research on Mars. Many of the data, particularly with respect to outcrops at Victoria Crater, have been only partially analyzed. Here, the previously published geochemical profile of Endurance Crater is compared to that of Victoria Crater, to understand aspects of the post-depositional aqueous and chemical alteration of the Meridiani land surface. The landsurface bears cracking patterns similar to those produced by multiple episodes of wetting and drying in expansive materials on Earth. The geochemical profiles at both craters are nearly identical, suggesting (using mass balance methods) that a very chemically homogenous sedimentary deposit has been engulfed by the apparent surficial addition of S, Cl, and Br (and associated cations) since exposure to the atmosphere. The chemistry and mineralogy at both locations is one where the most insoluble of the added components resides near the land surface (Ca sulfates), and the more soluble components are concentrated at greater depths in a vertical pattern consistent with their solubility in water. The profiles, when compared to those on Earth (and to physical constraints), are most similar those generated by the downward movement of meteoric water. When this aqueous alteration and soil formation occurred is not well constrained, but the processes occurred between late Noachian (?) to late Amazonian times. The exposure of the Victoria crater walls, which occurred likely less than 107 y ago (late Amazonian), shows the accumulation of dust as well as evidence for aqueous concentration of NaBr and/or CaBr, possibly by deliquescence. By direct comparison to Earth, the regional soil at Meridiani Planum is a Typic Petrogypsid (a sulfate cemented arid soil), bearing similarities to very ancient soils formed in the Atacama Desert of Chile. The amount of water required to produce the soils ranges from a

  13. Nanoencapsulation of Aloe vera in Synthetic and Naturally Occurring Polymers by Electrohydrodynamic Processing of Interest in Food Technology and Bioactive Packaging.

    Science.gov (United States)

    Torres-Giner, Sergio; Wilkanowicz, Sabina; Melendez-Rodriguez, Beatriz; Lagaron, Jose M

    2017-06-07

    This work originally reports on the use of electrohydrodynamic processing (EHDP) to encapsulate Aloe vera (AV, Aloe barbadensis Miller) using both synthetic polymers, i.e., polyvinylpyrrolidone (PVP) and poly(vinyl alcohol) (PVOH), and naturally occurring polymers, i.e., barley starch (BS), whey protein concentrate (WPC), and maltodextrin. The AV leaf juice was used as the water-based solvent for EHDP, and the resultant biopolymer solution properties were evaluated to determine their effect on the process. Morphological analysis revealed that, at the optimal processing conditions, synthetic polymers mainly produced fiber-like structures, while naturally occurring polymers generated capsules. Average sizes ranged from 100 nm to above 3 μm. As a result of their different and optimal morphology and, hence, higher AV content, PVP, in the form of nanofibers, and WPC, of nanocapsules, were further selected to study the AV stability against ultraviolet (UV) light exposure. Fourier transform infrared (FTIR) spectroscopy confirmed the successful encapsulation of AV in the biopolymer matrices, presenting both encapsulants a high chemical interaction with the bioactive components. Ultraviolet-visible (UV-vis) spectroscopy showed that, while PVP nanofibers offered a poor effect on the AV degradation during UV light exposure (∼10% of stability after 5 h), WPC nanobeads delivered excellent protection (stability of >95% after 6 h). This was ascribed to positive interactions between WPC and the hydrophilic components of AV and the inherent UV-blocking and oxygen barrier properties provided by the protein. Therefore, electrospraying of food hydrocolloids interestingly appears as a novel potential nanotechnology tool toward the formulation of more stable functional foods and nutraceuticals.

  14. Are Extremes of Consumption in Eating Disorders Related to an Altered Balance between Reward and Inhibition?

    Science.gov (United States)

    Wierenga, Christina E; Ely, Alice; Bischoff-Grethe, Amanda; Bailer, Ursula F; Simmons, Alan N; Kaye, Walter H

    2014-01-01

    The primary defining characteristic of a diagnosis of an eating disorder (ED) is the "disturbance of eating or eating-related behavior that results in the altered consumption or absorption of food" (DSM V; American Psychiatric Association, 2013). There is a spectrum, ranging from those who severely restrict eating and become emaciated on one end to those who binge and overconsume, usually accompanied by some form of compensatory behaviors, on the other. How can we understand reasons for such extremes of food consummatory behaviors? Recent work on obesity and substance use disorders has identified behaviors and neural pathways that play a powerful role in human consummatory behaviors. That is, corticostriatal limbic and dorsal cognitive neural circuitry can make drugs and food rewarding, but also engage self-control mechanisms that may inhibit their use. Importantly, there is considerable evidence that alterations of these systems also occur in ED. This paper explores the hypothesis that an altered balance of reward and inhibition contributes to altered extremes of response to salient stimuli, such as food. We will review recent studies that show altered sensitivity to reward and punishment in ED, with evidence of altered activity in corticostriatal and insula processes with respect to monetary gains or losses, and tastes of palatable foods. We will also discuss evidence for a spectrum of extremes of inhibition and dysregulation behaviors in ED supported by studies suggesting that this is related to top-down self-control mechanisms. The lack of a mechanistic understanding of ED has thwarted efforts for evidence-based approaches to develop interventions. Understanding how ED behavior is encoded in neural circuits would provide a foundation for developing more specific and effective treatment approaches.

  15. Co-Occurring Disorders

    Science.gov (United States)

    ... the mental health field. Alcohol and Drug Abuse, Addiction and Co-occurring Disorders: Co-occurring Disorders and ... 500 Montgomery Street, Suite 820 Alexandria, VA 22314 Phone (703) 684.7722 Toll Free (800) 969.6642 ...

  16. Proprotein Convertases Process Pmel17 during Secretion*

    Science.gov (United States)

    Leonhardt, Ralf M.; Vigneron, Nathalie; Rahner, Christoph; Cresswell, Peter

    2011-01-01

    Pmel17 is a melanocyte/melanoma-specific protein that traffics to melanosomes where it forms a fibrillar matrix on which melanin gets deposited. Before being cleaved into smaller fibrillogenic fragments the protein undergoes processing by proprotein convertases, a class of serine proteases that typically recognize the canonical motif RX(R/K)R↓. The current model of Pmel17 maturation states that this processing step occurs in melanosomes, but in light of recent reports this issue has become controversial. We therefore addressed this question by thoroughly assessing the processing kinetics of either wild-type Pmel17 or a secreted soluble Pmel17 derivative. Our results demonstrate clearly that processing of Pmel17 occurs during secretion and that it does not require entry of the protein into the endocytic system. Strikingly, processing proceeds even in the presence of the secretion inhibitor monensin, suggesting that Pmel17 is an exceptionally good substrate. In line with this, we find that newly synthesized surface Pmel17 is already quantitatively cleaved. Moreover, we demonstrate that Pmel17 function is independent of the sequence identity of its unconventional proprotein convertase-cleavage motif that lacks arginine in P4 position. The data alter the current view of Pmel17 maturation and suggest that the multistep processing of Pmel17 begins with an early cleavage during secretion that primes the protein for later functional processing. PMID:21247888

  17. Puberty and Adolescence as a Time of Vulnerability to Stressors that Alter Neurobehavioral Processes

    Science.gov (United States)

    Holder, Mary K.; Blaustein, Jeffrey D.

    2013-01-01

    Puberty and adolescence are major life transitions during which an individual’s physiology and behavior changes from that of a juvenile to that of an adult. Here we review studies documenting the effects of stressors during pubertal and adolescent development on the adult brain and behavior. The experience of complex or compound stressors during puberty/adolescence generally increases stress reactivity, increases anxiety and depression, and decreases cognitive performance in adulthood. These behavioral changes correlate with decreased hippocampal volumes and alterations in neural plasticity. Moreover, stressful experiences during puberty disrupt behavioral responses to gonadal hormones both in sexual performance and on cognition and emotionality. These behavioral changes correlate with altered estrogen receptor densities in some estrogen-concentrating brain areas, suggesting a remodeling of the brain’s response to hormones. A hypothesis is presented that activation of the immune system results in chronic neuroinflammation that may mediate the alterations of hormone-modulated behaviors in adulthood. PMID:24184692

  18. Marine ecosystem acoustics (MEA): Quantifying processes in the sea at the spatio-temporal scales on which they occur

    KAUST Repository

    Godøl, Olav Rune

    2014-07-22

    Sustainable management of fisheries resources requires quantitative knowledge and understanding of species distribution, abundance, and productivity-determining processes. Conventional sampling by physical capture is inconsistent with the spatial and temporal scales on which many of these processes occur. In contrast, acoustic observations can be obtained on spatial scales from centimetres to ocean basins, and temporal scales from seconds to seasons. The concept of marine ecosystem acoustics (MEA) is founded on the basic capability of acoustics to detect, classify, and quantify organisms and biological and physical heterogeneities in the water column. Acoustics observations integrate operational technologies, platforms, and models and can generate information by taxon at the relevant scales. The gaps between single-species assessment and ecosystem-based management, as well as between fisheries oceanography and ecology, are thereby bridged. The MEA concept combines state-of-the-art acoustic technology with advanced operational capabilities and tailored modelling integrated into a flexible tool for ecosystem research and monitoring. Case studies are presented to illustrate application of the MEA concept in quantification of biophysical coupling, patchiness of organisms, predator-prey interactions, and fish stock recruitment processes. Widespread implementation of MEA will have a large impact on marine monitoring and assessment practices and it is to be hoped that they also promote and facilitate interaction among disciplines within the marine sciences.

  19. Prism adaptation does not alter configural processing of faces [v1; ref status: indexed, http://f1000r.es/1wk

    Directory of Open Access Journals (Sweden)

    Janet H. Bultitude

    2013-10-01

    Full Text Available Patients with hemispatial neglect (‘neglect’ following a brain lesion show difficulty responding or orienting to objects and events on the left side of space. Substantial evidence supports the use of a sensorimotor training technique called prism adaptation as a treatment for neglect. Reaching for visual targets viewed through prismatic lenses that induce a rightward shift in the visual image results in a leftward recalibration of reaching movements that is accompanied by a reduction of symptoms in patients with neglect. The understanding of prism adaptation has also been advanced through studies of healthy participants, in whom adaptation to leftward prismatic shifts results in temporary neglect-like performance. Interestingly, prism adaptation can also alter aspects of non-lateralised spatial attention. We previously demonstrated that prism adaptation alters the extent to which neglect patients and healthy participants process local features versus global configurations of visual stimuli. Since deficits in non-lateralised spatial attention are thought to contribute to the severity of neglect symptoms, it is possible that the effect of prism adaptation on these deficits contributes to its efficacy. This study examines the pervasiveness of the effects of prism adaptation on perception by examining the effect of prism adaptation on configural face processing using a composite face task. The composite face task is a persuasive demonstration of the automatic global-level processing of faces: the top and bottom halves of two familiar faces form a seemingly new, unknown face when viewed together. Participants identified the top or bottom halves of composite faces before and after prism adaptation. Sensorimotor adaptation was confirmed by significant pointing aftereffect, however there was no significant change in the extent to which the irrelevant face half interfered with processing. The results support the proposal that the therapeutic effects

  20. Alterations in the proteome of the Euprymna scolopes light organ in response to symbiotic Vibrio fischeri.

    Science.gov (United States)

    Doino Lemus, J; McFall-Ngai, M J

    2000-09-01

    During the onset of the cooperative association between the Hawaiian sepiolid squid Euprymna scolopes and the marine luminous bacterium Vibrio fischeri, the anatomy and morphology of the host's symbiotic organ undergo dramatic changes that require interaction with the bacteria. This morphogenetic process involves an array of tissues, including those in direct contact with, as well as those remote from, the symbiotic bacteria. The bacteria induce the developmental program soon after colonization of the organ, although complete morphogenesis requires 96 h. In this study, to determine critical time points, we examined the biochemistry underlying bacterium-induced host development using two-dimensional polyacrylamide gel electrophoresis. Specifically, V. fischeri-induced changes in the soluble proteome of the symbiotic organ during the first 96 h of symbiosis were identified by comparing the protein profiles of symbiont-colonized and uncolonized organs. Both symbiosis-related changes and age-related changes were analyzed to determine what proportion of the differences in the proteomes was the result of specific responses to interaction with bacteria. Although no differences were detected over the first 24 h, numerous symbiosis-related changes became apparent at 48 and 96 h and were more abundant than age-related changes. In addition, many age-related protein changes occurred 48 h sooner in symbiotic animals, suggesting that the interaction of squid tissue with V. fischeri cells accelerates certain developmental processes of the symbiotic organ. These data suggest that V. fischeri-induced modifications in host tissues that occur in the first 24 h of the symbiosis are independent of marked alterations in the patterns of abundant proteins but that the full 4-day morphogenetic program requires significant alteration of the host soluble proteome.

  1. Hydrothermal Alteration of the Mt Unzen Conduit (Shimabara/Japan)

    Science.gov (United States)

    Yilmaz, T. I.; Mayer, K.; Hess, K. U.; Janots, E.; Gilg, H. A.; Dingwell, D. B.

    2016-12-01

    Investigations were carried out on hydrothermally altered coherent dacitic dykes samples from (USDP-4) drill core at Mt Unzen stratovolcano (Shimabara/Japan). XRF, XRD, EMPA, and C-O-isotope analysis led to insights concerning chemistry, mineralogy, and intensity of alteration as well as the origin of carbonate-precipitating fluids. Additionally a textural characterization of the occurring replacement features in the magma conduit zone was performed. The occurrence of the main secondary phases such as chlorite, pyrite, carbonates, and R1 (Reichweite parameter) illite-smectite indicate a weak to moderate propylitic to phyllic hydrothermal alteration. The dacitic samples of the dykes show different hydrothermal alteration features: (i) carbonate pseudomorphs after hornblende as well as core and zonal textures due to replacement of plagioclase by R1 illite-smectite, (ii) colloform banded fracture fillings and fillings in dissolution vugs, and (iii) chlorite and R1 illite-smectite in the groundmass. Carbonates in fractures comprise iron-rich dolomite solid solutions ("ankerite") and calcite. Isotopic values of d13Cvpdb = -4.59 ± 0.6‰ and d18Ovpdb = -21.73 ± 0.5‰ indicate a hydrothermal-magmatic origin for the carbonate formation. The chlorite-carbonate-pyrite index (CCPI) and the Ishikawa alteration index (AI), applied to the investigated samples show significant differences (CCPI=52.7-57.8; AI=36.1-40.6) indicating their different degree of alteration. According to Nakada et al., 2005, the C13 to C16 dykes represent the feeder dyke from the latest eruption (1991-1995) whereas C8 represents an earlier dyke feeder dyke from an older eruption. Weakest conduit alteration, which was obtained in samples C16-1-5 and C13-2-5, correlates with the alteration degree of the pristine dome rocks. Highest CCPI value was determined for sample C14-1-5 and the highest AI value was determined for sample C15-2-6. The degrees of alteration do not indicate highest alteration of the

  2. How broad and deep is the region of chemical alteration of oceanic plates at trenches?

    Science.gov (United States)

    Ranero, C. R.; Grevemeyer, I.; Barckhausen, U.

    2017-12-01

    Different lines of evidence indicate that oceanic plates are affected by pervasive bending-related deformation approaching ocean trenches. Results from active-seismic work support that deformation provides paths for exchange between hydrosphere and lithosphere, possibly causing chemical alteration of the incoming lithosphere. Much work focused on the potential transformation of peridotite to serpentine in the uppermost mantle of incoming plates, but there is no consensus on the region where it may occur or the intensity of alteration, let alone on limiting factors for the process. Teleseismic (large-great) earthquakes with normal-fault mechanism in the outer rise region have been often called to speculate on the depth of penetration of plate hydration. However, large-great outer-rise earthquakes may be related to stress changes due to slab pull after decoupling along the inter-plate boundary, and not necessarily controlled by bending stresses only. If so, the majority of the time the depth of water percolation may be related to local bending stresses expressed by micro-earthquakes rather than large events. Seismic images and multibeam bathymetry from lithosphere of similar thermal thickness from different trenches display a remarkable variability of the intensity of bending-related deformation along the subduction zones where plate age does not change significantly indicating that the intensity of deformation (not the depth) and perhaps hydration is very variable in space and not controlled by plate age. Seismic images showing hundreds of kilometers perpendicular to the trench into the incoming plate show that the bending-related deformation reaches mantle under the outer rise, well before the lithosphere plunges into the trench and develops the marked bend-faulting fabric observable in bathymetric maps. Thus, alteration occurs in a hundreds-of-km wide area, with deformation intensity related to local characteristics, and deformation depth to plate age.

  3. IMBALANCE OF DNA METHYLATION, BOTH HYPERMETHYLATION AND HYPOMETHYLATION, OCCUR AFTER EXPOSURE OF HUMAN CELLS TO NANOMOLAR CONCENTRATIONS OF ARSENITE IN CULTURE.

    Science.gov (United States)

    Imbalance of DNA methylation, BOTH hypermethylation and hypomethylation, occur after exposure of human cells to nanomolar concentrations of arsenite in culture.We and others have hypothesized that a mechanism of arsenic carcinogenesis could involve alteration of DNA methy...

  4. A model for Nb-Zr-REE-Ga enrichment in Lopingian altered alkaline volcanic ashes: Key evidence of H-O isotopes

    Science.gov (United States)

    Dai, Shifeng; Nechaev, Victor P.; Chekryzhov, Igor Yu.; Zhao, Lixin; Vysotskiy, Sergei V.; Graham, Ian; Ward, Colin R.; Ignatiev, Alexander V.; Velivetskaya, Tatyana A.; Zhao, Lei; French, David; Hower, James C.

    2018-03-01

    Clay-altered volcanic ash with highly-elevated concentrations of Nb(Ta), Zr(Hf), rare earth elements (REE), and Ga, is a new type of critical metal deposit with high commercial prospects that has been discovered in Yunnan Province, southwest China. Previous studies showed that the volcanic ashes had been subjected to hydrothermal fluids, the nature of which, however, is not clear. Here we show that the volcanic ashes were originated from alkaline magmatism, followed by a continuous hydrothermal-weathering process. Heated meteoric waters, which were sourced from acidic rains and mixed with CO2 from degassing of the Emeishan plume, have caused partial, but widespread, acidic leaching of Nb, Ta, Zr, Hf, REE, and Ga into ground water and residual enrichment of these elements, along with Al and Ti, in the deeply altered rocks. Subsequent alteration occurring under cooler, neutral or alkaline conditions, caused by water-rock interaction, resulted in precipitation of the leached critical metals in the deposit. Polymetallic mineralization of similar origin may be found in other continental regions subjected to explosive alkaline volcanism associated with deep weathering in humid conditions.

  5. The genetic alteration of retinoblastoma gene in esophageal cancer

    International Nuclear Information System (INIS)

    Cho, Jae Il; Shim, Yung Mok; Kim, Chang Min

    1994-12-01

    Retinoblastoma(RB) gene is the prototype of tumor suppressor gene and it's alteration have been frequently observed in a large number of human tumors. To investigate the role of RB in esophageal cancer, we studied 36 esophageal cancer tissues with Southern blot analysis to detect gross LOH and PCR-SSCP method to find minute LOH and mutation, if any. In the cases with abnormalities, the nucleotide sequence analysis was performed. Allelic loss of chromosome 13q14 occurred in 20 out of 32 informative cases (62.5%) by Southern analysis. Furthermore, PCR-LOH added three positive cases. Mobility shift by PCR-SSCP was observed in one case at exon 22, which showed 1 bp deletion in codon 771 of RB gene resulting in frame shift mutation. Besides, nine PCR-band alteration in tumor tissue compared with normal tissue were observed in exon 14 and 22, but mutation was not found on sequencing analysis suggesting the epigenetic alteration in tumor tissue. Analysis of the clinical data did not show any difference depending upon RB alteration. However, the total incidence of RB gene may play an important role in the development of esophageal cancer. The main genetic alteration of RB gene was deletion detected by Southern blot and one bp deletion leading to frame shift was also observed. 8 figs, 5 tabs. (Author)

  6. The genetic alteration of retinoblastoma gene in esophageal cancer

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Jae Il; Shim, Yung Mok; Kim, Chang Min [Korea Cancer Center Hospital of Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1994-12-01

    Retinoblastoma(RB) gene is the prototype of tumor suppressor gene and it`s alteration have been frequently observed in a large number of human tumors. To investigate the role of RB in esophageal cancer, we studied 36 esophageal cancer tissues with Southern blot analysis to detect gross LOH and PCR-SSCP method to find minute LOH and mutation, if any. In the cases with abnormalities, the nucleotide sequence analysis was performed. Allelic loss of chromosome 13q14 occurred in 20 out of 32 informative cases (62.5%) by Southern analysis. Furthermore, PCR-LOH added three positive cases. Mobility shift by PCR-SSCP was observed in one case at exon 22, which showed 1 bp deletion in codon 771 of RB gene resulting in frame shift mutation. Besides, nine PCR-band alteration in tumor tissue compared with normal tissue were observed in exon 14 and 22, but mutation was not found on sequencing analysis suggesting the epigenetic alteration in tumor tissue. Analysis of the clinical data did not show any difference depending upon RB alteration. However, the total incidence of RB gene may play an important role in the development of esophageal cancer. The main genetic alteration of RB gene was deletion detected by Southern blot and one bp deletion leading to frame shift was also observed. 8 figs, 5 tabs. (Author).

  7. Environmental parameters altered by climate change affect the activity of soil microorganisms involved in bioremediation.

    Science.gov (United States)

    Alkorta, Itziar; Epelde, Lur; Garbisu, Carlos

    2017-10-16

    Bioremediation, based on the use of microorganisms to break down pollutants, can be very effective at reducing soil pollution. But the climate change we are now experiencing is bound to have an impact on bioremediation performance, since the activity and degrading abilities of soil microorganisms are dependent on a series of environmental parameters that are themselves being altered by climate change, such as soil temperature, moisture, amount of root exudates, etc. Many climate-induced effects on soil microorganisms occur indirectly through changes in plant growth and physiology derived from increased atmospheric CO2 concentrations and temperatures, the alteration of precipitation patterns, etc., with a concomitant effect on rhizoremediation performance (i.e. the plant-assisted microbial degradation of pollutants in the rhizosphere). But these effects are extremely complex and mediated by processes such as acclimation and adaptation. Besides, soil microorganisms form complex networks of interactions with a myriad of organisms from many taxonomic groups that will also be affected by climate change, further complicating data interpretation. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  8. Effect of Hydrologic Alteration on the Community Succession of Macrophytes at Xiangyang Site, Hanjiang River, China.

    Science.gov (United States)

    Yang, Na; Zhang, Yehui; Duan, Kai

    2017-01-01

    With the intensification of human activities over the past three decades in China, adverse effects on river ecosystem become more serious especially in the Hanjiang River. Xiangyang site is an important spawn ground for four domestic fishes in the downstream region of Hanjiang River. Based on the field survey results of macrophytes during 1997-2000 and 2013-2014, community succession of aquatic macrophytes at Xiangyang site was evaluated and discussed. Two-key ecologic-related hydrologic characteristics, flow regime and water level, were identified as the main influence factors. The EFC (environmental flow components) parameters were adopted to evaluate the alteration of flow regimes at Xiangyang site during 1941-2013. Evaluation results demonstrate a highly altered flow process after being regulated by reservoir. The flow patterns tend to be an attenuation process with no large floods occurring but a higher monthly low flow. Furthermore, the water level decreased and fluctuation reduced after the dam was built, which caused the decrease of biomass but favored the submerged macrophytes during 1995-2009. However, with the water level increasing after 2010 and gently fluctuating, due to uplift by the hydraulic projects downstream as well as the flow attenuation, the dominant position of submerged macrophytes will be weakened.

  9. Are extremes of consumption in eating disorders related to an altered balance between reward and inhibition?

    Directory of Open Access Journals (Sweden)

    Christina E Wierenga

    2014-12-01

    Full Text Available The primary defining characteristic of a diagnosis of an eating disorder (ED is the disturbance of eating or eating-related behavior that results in the altered consumption or absorption of food (DSM V; American Psychiatric Association, 2013. There is a spectrum, ranging from those who severely restrict eating and become emaciated on one end to those who binge and overconsume, usually accompanied by some form of compensatory behaviors, on the other. How can we understand reasons for such extremes of food consummatory behaviors? Recent work on obesity and substance use disorders has identified behaviors and neural pathways that play a powerful role in human consummatory behaviors. That is, corticostriatal limbic and dorsal cognitive neural circuitry can make drugs and food rewarding, but also engage self-control mechanisms that may inhibit their use. Importantly, there is considerable evidence that alterations of these systems also occur in ED. This paper explores the hypothesis that an altered balance of reward and inhibition contributes to altered extremes of response to salient stimuli, such as food. We will review recent studies that show altered sensitivity to reward and punishment in ED, with evidence of altered activity in corticostriatal and insula processes with respect to monetary gains or losses, and tastes of palatable foods. We will also discuss evidence for a spectrum of extremes of inhibition and dysregulation behaviors in ED supported by studies suggesting that this is related to top-down self-control mechanisms. The lack of a mechanistic understanding of ED has thwarted efforts for evidence-based approaches to develop interventions. Understanding how ED behavior is encoded in neural circuits would provide a foundation for developing more specific and effective treatment approaches.

  10. Study of Alterations in Lipid Profile After Burn Injury.

    Directory of Open Access Journals (Sweden)

    Dr.Asha Khubchandani

    2017-06-01

    Full Text Available Introduction: After burn injury, changes in lipid profile occur in body. Dyslipidemia after burn injury is one of the important alterations. Objective: To check alterations in lipid profile after burn injury. Materials and Method: It was cross sectional study which was carried out on 250 burns patients of both sex, with an age group of 18-45 years, and varying burns percentage of 20-80% of total body surface area (TBSA. Serum cholesterol, serum LDL, serum HDL and serum triglyceride level were measured on XL-640 fully-auto biochemical analyser. Serum LDL and HDL were measured by Accelerator Selective Detergent Method. Serum cholesterol and triglyceride were measured by Trindor’s method. Results: Results showed decrease in serum cholesterol, serum LDL and serum HDL, while increase in serum triglyceride level in burns patients compared to normal subjects. Conclusion: This study clearly showed the importance of measuring serum cholesterol, TG, LDL and HDL in burn patients and targeting changes that occur in their levels along the burns course, which may have beneficial effect in protection from organ damage, increasing survival rates and improving burn outcome.

  11. When modularization fails to occur: a developmental perspective.

    Science.gov (United States)

    D'Souza, Dean; Karmiloff-Smith, Annette

    2011-05-01

    We argue that models of adult cognition defined in terms of independently functioning modules cannot be applied to development, whether typical or atypical. The infant brain starts out highly interconnected, and it is only over developmental time that neural networks become increasingly specialized-that is, relatively modularized. In the case of atypical development, even when behavioural scores fall within the normal range, they are frequently underpinned by different cognitive and neural processes. In other words, in neurodevelopmental disorders the gradual process of relative modularization may fail to occur.

  12. Highly sensitivity adhesion molecules detection in hereditary haemochromatosis patients reveals altered expression.

    LENUS (Irish Health Repository)

    Norris, S

    2012-02-01

    Several abnormalities in the immune status of patients with hereditary haemochromatosis (HH) have been reported, suggesting an imbalance in their immune function. This may include persistent production of, or exposure to, altered immune signalling contributing to the pathogenesis of this disorder. Adhesion molecules L-, E- and P-Selectin, intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) are some of the major regulators of the immune processes and altered levels of these proteins have been found in pathological states including cardiovascular diseases, arthritis and liver cancer. The aim of this study was to assess L-, E- and P-Selectin, ICAM-1 and VCAM-1 expression in patients with HH and correlate these results with HFE mutation status and iron indexes. A total of 139 subjects were diagnosed with HH (C282Y homozygotes = 87, C282Y\\/H63D = 26 heterozygotes, H63D homozygotes = 26), 27 healthy control subjects with no HFE mutation (N\\/N), 18 normal subjects heterozygous for the H63D mutation served as age-sex-matched controls. We observed a significant decrease in L-selectin (P = 0.0002) and increased E-selectin and ICAM-1 (P = 0.0006 and P = 0.0059) expression in HH patients compared with healthy controls. This study observes for the first time that an altered adhesion molecules profile occurs in patients with HH that is associated with specific HFE genetic component for iron overload, suggesting that differential expression of adhesion molecules may play a role in the pathogenesis of HH.

  13. Alterations of the Deltoid Muscle After Open Versus Arthroscopic Rotator Cuff Repair.

    Science.gov (United States)

    Cho, Nam Su; Cha, Sang Won; Rhee, Yong Girl

    2015-12-01

    Open repair can be more useful than arthroscopic repair for immobile and severely retracted, large to massive rotator cuff tears. However, it is not known whether the deltoid muscle is altered after open repair or to what extent the deltoid origin remains detached after surgery. To compare postoperative alterations of the deltoid muscle in open versus arthroscopic repair for severely retracted, large to massive rotator cuff tears. Case-control study; Level of evidence, 3. Enrolled in this study were 135 patients who underwent surgical repair for severely retracted, large to massive rotator cuff tears and who had routine follow-up MRIs at least 6 months after surgery. Open repairs were performed in 56 cases and arthroscopic repairs in 79 cases. The detachment and thickness of the deltoid muscle at its proximal origin were recorded in 5 zones on MRI. The alterations of the deltoid muscle and postoperative integrity of the repaired rotator cuff were evaluated. Partial detachment of the deltoid occurred in 1 patient (1.8%) in the open group and in 2 patients (2.5%) in the arthroscopic group (P = .80). All the partial detachments occurred in zones 2 and 3. Attenuation of the proximal origin of the deltoid was found in 3 patients (5.4%) in the open group and in 4 patients (5.1%) in the arthroscopic group (P = .87). Atrophy of the deltoid muscle was shown in 3 patients (5.4%) in the open group and 4 patients (5.1%) in the arthroscopic group (P = .61). The retear rate of the repaired cuff was 30.4% (17/56) in the open group and 38.0% (30/79) in the arthroscopic group (P = .74). Between open and arthroscopic repair for severely retracted, large to massive rotator cuff tears, there was no significant difference in detachment of the deltoid origin and alterations of the deltoid muscle after repair. Postoperative alterations of the deltoid occurred in arthroscopic surgery as well as in open surgery. For immobile massive rotator cuff tear, open repair is an acceptable technique

  14. Finding the traces of behavioral and cognitive processes in big data and naturally occurring datasets.

    Science.gov (United States)

    Paxton, Alexandra; Griffiths, Thomas L

    2017-10-01

    Today, people generate and store more data than ever before as they interact with both real and virtual environments. These digital traces of behavior and cognition offer cognitive scientists and psychologists an unprecedented opportunity to test theories outside the laboratory. Despite general excitement about big data and naturally occurring datasets among researchers, three "gaps" stand in the way of their wider adoption in theory-driven research: the imagination gap, the skills gap, and the culture gap. We outline an approach to bridging these three gaps while respecting our responsibilities to the public as participants in and consumers of the resulting research. To that end, we introduce Data on the Mind ( http://www.dataonthemind.org ), a community-focused initiative aimed at meeting the unprecedented challenges and opportunities of theory-driven research with big data and naturally occurring datasets. We argue that big data and naturally occurring datasets are most powerfully used to supplement-not supplant-traditional experimental paradigms in order to understand human behavior and cognition, and we highlight emerging ethical issues related to the collection, sharing, and use of these powerful datasets.

  15. Auditory N1 reveals planning and monitoring processes during music performance.

    Science.gov (United States)

    Mathias, Brian; Gehring, William J; Palmer, Caroline

    2017-02-01

    The current study investigated the relationship between planning processes and feedback monitoring during music performance, a complex task in which performers prepare upcoming events while monitoring their sensory outcomes. Theories of action planning in auditory-motor production tasks propose that the planning of future events co-occurs with the perception of auditory feedback. This study investigated the neural correlates of planning and feedback monitoring by manipulating the contents of auditory feedback during music performance. Pianists memorized and performed melodies at a cued tempo in a synchronization-continuation task while the EEG was recorded. During performance, auditory feedback associated with single melody tones was occasionally substituted with tones corresponding to future (next), present (current), or past (previous) melody tones. Only future-oriented altered feedback disrupted behavior: Future-oriented feedback caused pianists to slow down on the subsequent tone more than past-oriented feedback, and amplitudes of the auditory N1 potential elicited by the tone immediately following the altered feedback were larger for future-oriented than for past-oriented or noncontextual (unrelated) altered feedback; larger N1 amplitudes were associated with greater slowing following altered feedback in the future condition only. Feedback-related negativities were elicited in all altered feedback conditions. In sum, behavioral and neural evidence suggests that future-oriented feedback disrupts performance more than past-oriented feedback, consistent with planning theories that posit similarity-based interference between feedback and planning contents. Neural sensory processing of auditory feedback, reflected in the N1 ERP, may serve as a marker for temporal disruption caused by altered auditory feedback in auditory-motor production tasks. © 2016 Society for Psychophysiological Research.

  16. Adaptive optics without altering visual perception.

    Science.gov (United States)

    Koenig, D E; Hart, N W; Hofer, H J

    2014-04-01

    Adaptive optics combined with visual psychophysics creates the potential to study the relationship between visual function and the retina at the cellular scale. This potential is hampered, however, by visual interference from the wavefront-sensing beacon used during correction. For example, we have previously shown that even a dim, visible beacon can alter stimulus perception (Hofer et al., 2012). Here we describe a simple strategy employing a longer wavelength (980nm) beacon that, in conjunction with appropriate restriction on timing and placement, allowed us to perform psychophysics when dark adapted without altering visual perception. The method was verified by comparing detection and color appearance of foveally presented small spot stimuli with and without the wavefront beacon present in 5 subjects. As an important caution, we found that significant perceptual interference can occur even with a subliminal beacon when additional measures are not taken to limit exposure. Consequently, the lack of perceptual interference should be verified for a given system, and not assumed based on invisibility of the beacon. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Covalent DNA-protein crosslinking occurs after hyperthermia and radiation

    International Nuclear Information System (INIS)

    Cress, A.E.; Bowden, G.T.

    1983-01-01

    Covalent DNA-protein crosslinks occur in exponentially growing mouse leukemia cells (L1210) after exposure to ionizing radiation. The amount of DNA-protein crosslinks as measured by a filter binding assay is dose dependent upon x irradiation. Although hyperthermia and radiation in combination are synergistic with respect to cell lethality, the combination does not result in an increase of DNA-protein crosslinks when assayed immediately following treatments. Hyperthermia (43 0 C/15 min) given prior to radiation dose not alter the radiation dose dependency of the amount of initial crosslinking. In addition, the amount of DNA-protein crosslinking produced by heat plus radiation is independent of the length of heating the cells at 43 0 C. The DNA-protein crosslinks produced y 50-Gy x ray alone are removed after 2 hr at 37 0 C. However, if hyperthermia (43 0 C/15 min) is given prior to 100-Gy x ray, the removal of DNA-protein crosslinks is delayed until 4.0 hr after radiation. Phospho-serine and phospho-threonine bonds are not produced with either radiation or the combination of hyperthermia plus radiation as judged by the resistance of the bonds to guanidine hydrochloride. However, hyperthermia plus radiation causes an increase in phosphate to nitrogen type bonding. These results show that radiation alone causes covalent DNA-protein crosslinks. Hyperthermia in combination with radiation does not increase the total amount of the crosslinks but delays the removal of the crosslinks and alters the distribution of the types of chemical bonding

  18. Insulin resistance alters islet morphology in nondiabetic humans

    DEFF Research Database (Denmark)

    Mezza, Teresa; Muscogiuri, Giovanna; Sorice, Gian Pio

    2014-01-01

    Type 2 diabetes is characterized by poor glucose uptake in metabolic tissues and manifests when insulin secretion fails to cope with worsening insulin resistance. In addition to its effects on skeletal muscle, liver, and adipose tissue metabolism, it is evident that insulin resistance also affects...... pancreatic β-cells. To directly examine the alterations that occur in islet morphology as part of an adaptive mechanism to insulin resistance, we evaluated pancreas samples obtained during pancreatoduodenectomy from nondiabetic subjects who were insulin-resistant or insulin-sensitive. We also compared...... insulin sensitivity, insulin secretion, and incretin levels between the two groups. We report an increased islet size and an elevated number of β- and α-cells that resulted in an altered β-cell-to-α-cell area in the insulin- resistant group. Our data in this series of studies suggest that neogenesis from...

  19. Altered joint tribology in osteoarthritis: Reduced lubricin synthesis due to the inflammatory process. New horizons for therapeutic approaches.

    Science.gov (United States)

    Szychlinska, M A; Leonardi, R; Al-Qahtani, M; Mobasheri, A; Musumeci, G

    2016-06-01

    Osteoarthritis (OA) is the most common form of joint disease. This review aimed to consolidate the current evidence that implicates the inflammatory process in the attenuation of synovial lubrication and joint tissue homeostasis in OA. Moreover, with these findings, we propose some evidence for novel therapeutic strategies for preventing and/or treating this complex disorder. The studies reviewed support that inflammatory mediators participate in the onset and progression of OA after joint injury. The flow of pro-inflammatory cytokines following an acute injury seems to be directly associated with altered lubricating ability in the joint tissue. The latter is associated with reduced level of lubricin, one of the major joint lubricants. Future research should focus on the development of new therapies that attenuate the inflammatory process and restore lubricin synthesis and function. This approach could support joint tribology and synovial lubrication leading to improved joint function and pain relief. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  20. The epigenetic alterations of endogenous retroelements in aging.

    Science.gov (United States)

    Cardelli, Maurizio

    2018-02-16

    Endogenous retroelements, transposons that mobilize through RNA intermediates, include some of the most abundant repetitive sequences of the human genome, such as Alu and LINE-1 sequences, and human endogenous retroviruses. Recent discoveries demonstrate that these mobile genetic elements not only act as intragenomic parasites, but also exert regulatory roles in living cells. The risk of genomic instability represented by endogenous retroelements is normally counteracted by a series of epigenetic control mechanisms which include, among the most important, CpG DNA methylation. Indeed, most of the genomic CpG sites subjected to DNA methylation in the nuclear DNA are carried by these repetitive elements. As other parts of the genome, endogenous retroelements and other transposable elements are subjected to deep epigenetic alterations during aging, repeatedly observed in the context of organismal and cellular senescence, in human and other species. This review summarizes the current status of knowledge about the epigenetic alterations occurring in this large, non-genic portion of the genome in aging and age-related conditions, with a focus on the causes and the possible functional consequences of these alterations. Copyright © 2018 Elsevier B.V. All rights reserved.

  1. CO-occurring exposure to perchlorate, nitrate and thiocyanate alters thyroid function in healthy pregnant women

    International Nuclear Information System (INIS)

    Horton, Megan K.; Blount, Benjamin C.; Valentin-Blasini, Liza; Wapner, Ronald; Whyatt, Robin; Gennings, Chris; Factor-Litvak, Pam

    2015-01-01

    Background: Adequate maternal thyroid function during pregnancy is necessary for normal fetal brain development, making pregnancy a critical window of vulnerability to thyroid disrupting insults. Sodium/iodide symporter (NIS) inhibitors, namely perchlorate, nitrate, and thiocyanate, have been shown individually to competitively inhibit uptake of iodine by the thyroid. Several epidemiologic studies examined the association between these individual exposures and thyroid function. Few studies have examined the effect of this chemical mixture on thyroid function during pregnancy Objectives: We examined the cross sectional association between urinary perchlorate, thiocyanate and nitrate concentrations and thyroid function among healthy pregnant women living in New York City using weighted quantile sum (WQS) regression. Methods: We measured thyroid stimulating hormone (TSH) and free thyroxine (FreeT4) in blood samples; perchlorate, thiocyanate, nitrate and iodide in urine samples collected from 284 pregnant women at 12 (±2.8) weeks gestation. We examined associations between urinary analyte concentrations and TSH or FreeT4 using linear regression or WQS adjusting for gestational age, urinary iodide and creatinine. Results: Individual analyte concentrations in urine were significantly correlated (Spearman's r 0.4–0.5, p<0.001). Linear regression analyses did not suggest associations between individual concentrations and thyroid function. The WQS revealed a significant positive association between the weighted sum of urinary concentrations of the three analytes and increased TSH. Perchlorate had the largest weight in the index, indicating the largest contribution to the WQS. Conclusions: Co-exposure to perchlorate, nitrate and thiocyanate may alter maternal thyroid function, specifically TSH, during pregnancy. - Highlights: • Perchlorate, nitrate, thiocyanate and iodide measured in maternal urine. • Thyroid function (TSH and Free T4) measured in maternal blood

  2. CO-occurring exposure to perchlorate, nitrate and thiocyanate alters thyroid function in healthy pregnant women

    Energy Technology Data Exchange (ETDEWEB)

    Horton, Megan K., E-mail: megan.horton@mssm.edu [Department of Preventive Medicine, Icahn School of Medicine, New York, New York (United States); Blount, Benjamin C.; Valentin-Blasini, Liza [National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, Georgia (United States); Wapner, Ronald [Department of Obstetrics and Gynecology, Columbia University, New York, New York (United States); Whyatt, Robin [Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, New York (United States); Gennings, Chris [Department of Preventive Medicine, Icahn School of Medicine, New York, New York (United States); Factor-Litvak, Pam [Department of Epidemiology, Mailman School of Public Health, Columbia University, New York, New York (United States)

    2015-11-15

    Background: Adequate maternal thyroid function during pregnancy is necessary for normal fetal brain development, making pregnancy a critical window of vulnerability to thyroid disrupting insults. Sodium/iodide symporter (NIS) inhibitors, namely perchlorate, nitrate, and thiocyanate, have been shown individually to competitively inhibit uptake of iodine by the thyroid. Several epidemiologic studies examined the association between these individual exposures and thyroid function. Few studies have examined the effect of this chemical mixture on thyroid function during pregnancy Objectives: We examined the cross sectional association between urinary perchlorate, thiocyanate and nitrate concentrations and thyroid function among healthy pregnant women living in New York City using weighted quantile sum (WQS) regression. Methods: We measured thyroid stimulating hormone (TSH) and free thyroxine (FreeT4) in blood samples; perchlorate, thiocyanate, nitrate and iodide in urine samples collected from 284 pregnant women at 12 (±2.8) weeks gestation. We examined associations between urinary analyte concentrations and TSH or FreeT4 using linear regression or WQS adjusting for gestational age, urinary iodide and creatinine. Results: Individual analyte concentrations in urine were significantly correlated (Spearman's r 0.4–0.5, p<0.001). Linear regression analyses did not suggest associations between individual concentrations and thyroid function. The WQS revealed a significant positive association between the weighted sum of urinary concentrations of the three analytes and increased TSH. Perchlorate had the largest weight in the index, indicating the largest contribution to the WQS. Conclusions: Co-exposure to perchlorate, nitrate and thiocyanate may alter maternal thyroid function, specifically TSH, during pregnancy. - Highlights: • Perchlorate, nitrate, thiocyanate and iodide measured in maternal urine. • Thyroid function (TSH and Free T4) measured in maternal blood

  3. Aging induced ER stress alters sleep and sleep homeostasis

    Science.gov (United States)

    Brown, Marishka K.; Chan, May T.; Zimmerman, John E.; Pack, Allan I.; Jackson, Nicholas E.; Naidoo, Nirinjini

    2014-01-01

    Alterations in the quality, quantity and architecture of baseline and recovery sleep have been shown to occur during aging. Sleep deprivation induces endoplasmic reticular (ER) stress and upregulates a protective signaling pathway termed the unfolded protein response (UPR). The effectiveness of the adaptive UPR is diminished by age. Previously, we showed that endogenous chaperone levels altered recovery sleep in Drosophila melanogaster. We now report that acute administration of the chemical chaperone sodium 4-phenylbutyrate (PBA) reduces ER stress and ameliorates age-associated sleep changes in Drosophila. PBA consolidates both baseline and recovery sleep in aging flies. The behavioral modifications of PBA are linked to its suppression of ER stress. PBA decreased splicing of x-box binding protein 1 (XBP1) and upregulation of phosphorylated elongation initiation factor 2 α (p-eIF2α), in flies that were subjected to sleep deprivation. We also demonstrate that directly activating ER stress in young flies fragments baseline sleep and alters recovery sleep. Alleviating prolonged/sustained ER stress during aging contributes to sleep consolidation and improves recovery sleep/ sleep debt discharge. PMID:24444805

  4. Alteration zones: are they a good target for gold deposits in Egypt

    International Nuclear Information System (INIS)

    Botros, N.S.

    2002-01-01

    Extensive rock alterations are a clearly visible characteristic of most Egyptian gold deposits and occurrences. The alterations occur either surrounding the auriferous quartz veins and/or structurally controlled by specific structural features, such as fractures and shear surfaces. Some samples of these alteration zones have proved to be anomalously enriched in gold while others are completely barren. Accordingly there is a controversy on the merit of alteration zones as good lead to gold. Here, the various types of wall rocks wall-rock alteration are reviewed with a discussion on the possible reaction that could have generated them. It is concluded that two main styles of alterations could be recognized in the field. The first results during the liberation of gold from the source rocks, and is characterized by being widely distributed and spatial relation to major structures. The second style, however, is related to the deposition of gold and is recognizable only within a few meters of the auriferous quartz veins. The potentiality of each style is discussed and applications of concept are offered. In general, alterations accompanying the liberation of gold are not completely devoid of gold, but may still retain some gold depending on the mineralogical siting of gold in the source rocks. Moreover, this type of alteration is a good criterion for the presence of gold in the nearby sites. Alterations accompanying deposition of gold, on the other hand, constitute a good target for gold particularly the portions that are dissected by minor quartz veins, veinlets and stockworks (silicification) where gold is believed to migrate to such sites with silica liberated during the different types of alterations. The presence of some efficient precipitants, such as sulphides, carbonates, clay minerals, sericites, iron oxides, chlorite and graphite in the alteration zones is a good indicator of the alteration zone. (author)

  5. Speaking L2 in EFL Classes: Performance, Identity and Alterity

    Science.gov (United States)

    Forman, Ross

    2014-01-01

    When teachers and students use L2 in Expanding Circle, Asian EFL classes, what kind of interpersonal roles do they perform, and what does this mean for the development of L2-mediated identity? The notion of alterity, or otherness, is used here to analyse the extent to which identity work occurs in EFL classes located in a Thai university context.…

  6. Mineralization and hydrothermal alteration of the Tajroud vein system, south of Neyshabour

    Directory of Open Access Journals (Sweden)

    Mohsen Alikhani Banghani

    2013-10-01

    Full Text Available The Tajroud vein system is located 190 km southwest of Mashhad, and in the southern part of the Sabzevar zone. The vein host rocks consist of Eocene intermediate to silicic volcanic rocks. The mineralization occurs as open space filling, taking place as veins, veinlets and hydrothermal breccias. Based on field geology and textural evidence, three main stages of mineralization were identified. Stage I mainly contains quartz, pyrite, chalcopyrite and magnetite. Stage II, which has the same mineral assemblage as stage I, is the most important stage in terms of volume. Finally, stage III is characterized by repetitive quartz and calcite banding with negligible amounts of sulfide minerals. Hydrothermal alteration is developed around the veins and tends to be more intense in the vicinity of the veins. The plot of the Ishikawa alteration index (AI versus chlorite-carbonate-pyrite index (CCPI, known as alteration box plot, displays three main alteration trends. The hydrothermal alteration assemblage of quartz, adularia, chlorite, illite, calcite, and epidote that envelops the Tajroud vein system formed from the upwelling of near-neutral to weakly alkaline hydrothermal solutions. The mineralogic, alteration and geochemical characteristics of the studied area and comparison with epithermal ore deposits indicate that the Tajroud vein system represents an epithermal system of low-sulfidation type.

  7. A new method for defining and managing process alarms and for correcting process operation when an alarm occurs

    International Nuclear Information System (INIS)

    Brooks, Robin; Thorpe, Richard; Wilson, John

    2004-01-01

    A new mathematical treatment of alarms that considers them as multi-variable interactions between process variables has provided the first-ever method to calculate values for alarm limits. This has resulted in substantial reductions in false alarms and hence in alarm annunciation rates in field trials. It has also unified alarm management, process control and product quality control into a single mathematical framework so that operations improvement and hence economic benefits are obtained at the same time as increased process safety. Additionally, an algorithm has been developed that advises what changes should be made to Manipulable process variables to clear an alarm. The multi-variable Best Operating Zone at the heart of the method is derived from existing historical data using equation-free methods. It does not require a first-principles process model or an expensive series of process identification experiments. Integral with the method is a new format Process Operator Display that uses only existing variables to fully describe the multi-variable operating space. This combination of features makes it an affordable and maintainable solution for small plants and single items of equipment as well as for the largest plants. In many cases, it also provides the justification for the investments about to be made or already made in process historian systems. Field Trials have been and are being conducted at IneosChlor and Mallinckrodt Chemicals, both in the UK, of the new geometric process control (GPC) method for improving the quality of both process operations and product by providing Process Alarms and Alerts of much high quality than ever before. The paper describes the methods used, including a simple visual method for Alarm Rationalisation that quickly delivers large sets of Consistent Alarm Limits, and the extension to full Alert Management with highlights from the Field Trials to indicate the overall effectiveness of the method in practice

  8. A new method for defining and managing process alarms and for correcting process operation when an alarm occurs

    Energy Technology Data Exchange (ETDEWEB)

    Brooks, Robin [Curvaceous Software Limited, P.O. Box 43, Gerrards Cross, Bucks SL98UX (United Kingdom)]. E-mail: enquiries@curvaceous.com; Thorpe, Richard [Curvaceous Software Limited, P.O. Box 43, Gerrards Cross, Bucks SL98UX (United Kingdom); Wilson, John [Curvaceous Software Limited, P.O. Box 43, Gerrards Cross, Bucks SL98UX (United Kingdom)

    2004-11-11

    A new mathematical treatment of alarms that considers them as multi-variable interactions between process variables has provided the first-ever method to calculate values for alarm limits. This has resulted in substantial reductions in false alarms and hence in alarm annunciation rates in field trials. It has also unified alarm management, process control and product quality control into a single mathematical framework so that operations improvement and hence economic benefits are obtained at the same time as increased process safety. Additionally, an algorithm has been developed that advises what changes should be made to Manipulable process variables to clear an alarm. The multi-variable Best Operating Zone at the heart of the method is derived from existing historical data using equation-free methods. It does not require a first-principles process model or an expensive series of process identification experiments. Integral with the method is a new format Process Operator Display that uses only existing variables to fully describe the multi-variable operating space. This combination of features makes it an affordable and maintainable solution for small plants and single items of equipment as well as for the largest plants. In many cases, it also provides the justification for the investments about to be made or already made in process historian systems. Field Trials have been and are being conducted at IneosChlor and Mallinckrodt Chemicals, both in the UK, of the new geometric process control (GPC) method for improving the quality of both process operations and product by providing Process Alarms and Alerts of much high quality than ever before. The paper describes the methods used, including a simple visual method for Alarm Rationalisation that quickly delivers large sets of Consistent Alarm Limits, and the extension to full Alert Management with highlights from the Field Trials to indicate the overall effectiveness of the method in practice.

  9. A new method for defining and managing process alarms and for correcting process operation when an alarm occurs.

    Science.gov (United States)

    Brooks, Robin; Thorpe, Richard; Wilson, John

    2004-11-11

    A new mathematical treatment of alarms that considers them as multi-variable interactions between process variables has provided the first-ever method to calculate values for alarm limits. This has resulted in substantial reductions in false alarms and hence in alarm annunciation rates in field trials. It has also unified alarm management, process control and product quality control into a single mathematical framework so that operations improvement and hence economic benefits are obtained at the same time as increased process safety. Additionally, an algorithm has been developed that advises what changes should be made to Manipulable process variables to clear an alarm. The multi-variable Best Operating Zone at the heart of the method is derived from existing historical data using equation-free methods. It does not require a first-principles process model or an expensive series of process identification experiments. Integral with the method is a new format Process Operator Display that uses only existing variables to fully describe the multi-variable operating space. This combination of features makes it an affordable and maintainable solution for small plants and single items of equipment as well as for the largest plants. In many cases, it also provides the justification for the investments about to be made or already made in process historian systems. Field Trials have been and are being conducted at IneosChlor and Mallinckrodt Chemicals, both in the UK, of the new geometric process control (GPC) method for improving the quality of both process operations and product by providing Process Alarms and Alerts of much high quality than ever before. The paper describes the methods used, including a simple visual method for Alarm Rationalisation that quickly delivers large sets of Consistent Alarm Limits, and the extension to full Alert Management with highlights from the Field Trials to indicate the overall effectiveness of the method in practice.

  10. Assessment of the Alteration of Granitic Rocks and its Influence on Alkalis Release

    Science.gov (United States)

    Ferraz, Ana Rita; Fernandes, Isabel; Soares, Dora; Santos Silva, António; Quinta-Ferreira, Mário

    2017-12-01

    Several concrete structures had shown signs of degradation some years after construction due to internal expansive reactions. Among these reactions there are the alkali-aggregate reactions (AAR) that occur between the aggregates and the concrete interstitial fluids which can be divided in two types: the alkali-silica reaction (ASR) and alkali-carbonate reaction (ACR). The more common is the ASR which occurs when certain types of reactive silica are present in the aggregates. In consequence, an expansive alkali-silica gel is formed leading to the concrete cracking and degradation. Granites are rocks composed essentially of quartz, micas and feldspars, the latter being the minerals which contain more alkalis in their structure and thus, able to release them in conditions of high alkalinity. Although these aggregates are of slow reaction, some structures where they were applied show evidence of deterioration due to ASR some years or decades after the construction. In the present work, the possible contribution of granitic aggregates to the interstitial fluids of concrete by alkalis release was studied by performing chemical attack with NaOH and KOH solutions. Due to the heterogeneity of the quarries in what concerns the degree of alteration and/or fracturing, rock samples with different alteration were analysed. The alteration degree was characterized both under optical microscope and image analysis and compared with the results obtained from the chemical tests. It was concluded that natural alteration reduces dramatically the releasable alkalis available in the rocks.

  11. Epigenetic Alterations in Alzheimer's Disease

    Directory of Open Access Journals (Sweden)

    Johannes eGräff

    2015-12-01

    Full Text Available Alzheimer’s disease (AD is the major cause of dementia in Western societies. It progresses asymptomatically during decades before being belatedly diagnosed when therapeutic strategies have become unviable. Although several genetic alterations have been associated with AD, the vast majority of AD cases do not show strong genetic underpinnings and are thus considered a consequence of non-genetic factors. Epigenetic mechanisms allow for the integration of long-lasting non-genetic inputs on specific genetic backgrounds, and recently, a growing number of epigenetic alterations in AD have been described. For instance, an accumulation of dysregulated epigenetic mechanisms in aging, the predominant risk factor of AD, might facilitate the onset of the disease. Likewise, mutations in several enzymes of the epigenetic machinery have been associated with neurodegenerative processes that are altered in AD such as impaired learning and memory formation. Genome-wide and locus-specific epigenetic alterations have also been reported, and several epigenetically dysregulated genes validated by independent groups. From these studies, a picture emerges of AD as being associated with DNA hypermethylation and histone deacetylation, suggesting a general repressed chromatin state and epigenetically reduced plasticity in AD. Here we review these recent findings and discuss several technical and methodological considerations that are imperative for their correct interpretation. We also pay particular focus on potential implementations and theoretical frameworks that we expect will help to better direct future studies aimed to unravel the epigenetic participation in AD.

  12. Epigenetic Alterations in Alzheimer's Disease.

    Science.gov (United States)

    Sanchez-Mut, Jose V; Gräff, Johannes

    2015-01-01

    Alzheimer's disease (AD) is the major cause of dementia in Western societies. It progresses asymptomatically during decades before being belatedly diagnosed when therapeutic strategies have become unviable. Although several genetic alterations have been associated with AD, the vast majority of AD cases do not show strong genetic underpinnings and are thus considered a consequence of non-genetic factors. Epigenetic mechanisms allow for the integration of long-lasting non-genetic inputs on specific genetic backgrounds, and recently, a growing number of epigenetic alterations in AD have been described. For instance, an accumulation of dysregulated epigenetic mechanisms in aging, the predominant risk factor of AD, might facilitate the onset of the disease. Likewise, mutations in several enzymes of the epigenetic machinery have been associated with neurodegenerative processes that are altered in AD such as impaired learning and memory formation. Genome-wide and locus-specific epigenetic alterations have also been reported, and several epigenetically dysregulated genes validated by independent groups. From these studies, a picture emerges of AD as being associated with DNA hypermethylation and histone deacetylation, suggesting a general repressed chromatin state and epigenetically reduced plasticity in AD. Here we review these recent findings and discuss several technical and methodological considerations that are imperative for their correct interpretation. We also pay particular focus on potential implementations and theoretical frameworks that we expect will help to better direct future studies aimed to unravel the epigenetic participation in AD.

  13. Mapping advanced argillic alteration at Cuprite, Nevada, using imaging spectroscopy

    Science.gov (United States)

    Swayze, Gregg A.; Clark, Roger N.; Goetz, Alexander F.H.; Livo, K. Eric; Breit, George N.; Kruse, Fred A.; Sutley, Stephen J.; Snee, Lawrence W.; Lowers, Heather A.; Post, James L.; Stoffregen, Roger E.; Ashley, Roger P.

    2014-01-01

    Mineral maps based on Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) data were used to study late Miocene advanced argillic alteration at Cuprite, Nevada. Distributions of Fe-bearing minerals, clays, micas, sulfates, and carbonates were mapped using the Tetracorder spectral-shape matching system. The Al content of white micas increases toward altered areas and near intrusive rocks. Alunite composition varies from pure K to intimate mixtures of Na-K endmembers with subpixel occurrences of huangite, the Ca analogue of alunite. Intimately mixed Na-K alunite marks areas of relatively lower alteration temperature, whereas co-occurring Na-alunite and dickite may delineate relict hydrothermal conduits. The presence of dickite, halloysite, and well-ordered kaolinite, but absence of disordered kaolinite, is consistent with acidic conditions during hydrothermal alteration. Partial lichen cover on opal spectrally mimics chalcedony, limiting its detection to lichen-free areas. Pods of buddingtonite are remnants of initial quartz-adularia-smectite alteration. Thus, spectral maps provide a synoptic view of the surface mineralogy, and define a previously unrecognized early steam-heated hydrothermal event.Faulting and episodes of hydrothermal alteration at Cuprite were intimately linked to upper plate movements above the Silver Peak-Lone Mountain detachment and growth, collapse, and resurgence of the nearby Stonewall Mountain volcanic complex between 8 and 5 Ma. Isotopic dating indicates that hydrothermal activity started at least by 7.61 Ma and ended by about 6.2 Ma. Spectral and stable isotope data suggest that Cuprite is a late Miocene low-sulfidation adularia-sericite type hot spring deposit overprinted by late-stage, steam-heated advanced argillic alteration formed along the margin of the Stonewall Mountain caldera.

  14. Neurocognitive and electrophysiological evidence of altered face processing in parents of children with autism: implications for a model of abnormal development of social brain circuitry in autism.

    Science.gov (United States)

    Dawson, Geraldine; Webb, Sara Jane; Wijsman, Ellen; Schellenberg, Gerard; Estes, Annette; Munson, Jeffrey; Faja, Susan

    2005-01-01

    Neuroimaging and behavioral studies have shown that children and adults with autism have impaired face recognition. Individuals with autism also exhibit atypical event-related brain potentials to faces, characterized by a failure to show a negative component (N170) latency advantage to face compared to nonface stimuli and a bilateral, rather than right lateralized, pattern of N170 distribution. In this report, performance by 143 parents of children with autism on standardized verbal, visual-spatial, and face recognition tasks was examined. It was found that parents of children with autism exhibited a significant decrement in face recognition ability relative to their verbal and visual spatial abilities. Event-related brain potentials to face and nonface stimuli were examined in 21 parents of children with autism and 21 control adults. Parents of children with autism showed an atypical event-related potential response to faces, which mirrored the pattern shown by children and adults with autism. These results raise the possibility that face processing might be a functional trait marker of genetic susceptibility to autism. Discussion focuses on hypotheses regarding the neurodevelopmental and genetic basis of altered face processing in autism. A general model of the normal emergence of social brain circuitry in the first year of life is proposed, followed by a discussion of how the trajectory of normal development of social brain circuitry, including cortical specialization for face processing, is altered in individuals with autism. The hypothesis that genetic-mediated dysfunction of the dopamine reward system, especially its functioning in social contexts, might account for altered face processing in individuals with autism and their relatives is discussed.

  15. Translational Rodent Paradigms to Investigate Neuromechanisms Underlying Behaviors Relevant to Amotivation and Altered Reward Processing in Schizophrenia.

    Science.gov (United States)

    Young, Jared W; Markou, Athina

    2015-09-01

    Amotivation and reward-processing deficits have long been described in patients with schizophrenia and considered large contributors to patients' inability to integrate well in society. No effective treatments exist for these symptoms, partly because the neuromechanisms mediating such symptoms are poorly understood. Here, we propose a translational neuroscientific approach that can be used to assess reward/motivational deficits related to the negative symptoms of schizophrenia using behavioral paradigms that can also be conducted in experimental animals. By designing and using objective laboratory behavioral tools that are parallel in their parameters in rodents and humans, the neuromechanisms underlying behaviors with relevance to these symptoms of schizophrenia can be investigated. We describe tasks that measure the motivation of rodents to expend physical and cognitive effort to gain rewards, as well as probabilistic learning tasks that assess both reward learning and feedback-based decision making. The latter tasks are relevant because of demonstrated links of performance deficits correlating with negative symptoms in patients with schizophrenia. These tasks utilize operant techniques in order to investigate neural circuits targeting a specific domain across species. These tasks therefore enable the development of insights into altered mechanisms leading to negative symptom-relevant behaviors in patients with schizophrenia. Such findings will then enable the development of targeted treatments for these altered neuromechanisms and behaviors seen in schizophrenia. © The Author 2015. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  16. Hydrothermal alteration of deep fractured granite: Effects of dissolution and precipitation

    Science.gov (United States)

    Nishimoto, Shoji; Yoshida, Hidekazu

    2010-03-01

    This paper investigates the mineralogical effects of hydrothermal alteration at depth in fractures in granite. A fracture accompanied by an alteration halo and filled with clay was found at a depth of 200 m in a drill core through Toki granite, Gifu, central Japan. Microscopic observation, XRD, XRF, EPMA and SXAM investigations revealed that the microcrystalline clays consist of illite, quartz and pyrite and that the halo round the fracture can be subdivided into a phyllic zone adjacent to the fracture, surrounded by a propylitic zone in which Fe-phyllosilicates are present, and a distinctive outer alteration front characterized by plagioclase breakdown. The processes that result in these changes took place in three successive stages: 1) partial dissolution of plagioclase with partial chloritization of biotite; 2) biotite dissolution and precipitation of Fe-phyllosilicate in the dissolution pores; 3) dissolution of K-feldspar and Fe-phyllosilicate, and illite precipitation associated with development of microcracks. These hydrothermal alterations of the granite proceed mainly by a dissolution-precipitation process resulting from the infiltration of hydrothermal fluid along microcracks. Such infiltration causes locally high mobility of Al and increases the ratio of fluid to rock in the alteration halo. These results contribute to an understanding of how granitic rock becomes altered in orogenic fields such as the Japanese island arc.

  17. Geochemical, petrographic and physical characterizations and associated alterations of the volcanic rocks of the Romanesque San Nicola Church (Ottana, central Sardinia, Italy)

    Science.gov (United States)

    Columbu, Stefano; Palomba, Marcella; Sitzia, Fabio

    2015-04-01

    In this research, the volcanic rocks belonging to the Sardinia Oligo-Miocene volcanic cycle (32 - 11 Ma) and building up the structure of the San Nicola church, one of the most representative churches of the Romanesque architecture, were studied. These stones were widely used in medieval architecture for the excellent workability, but they present some disadvantages, since they are greatly affected by alteration phenomena. The main objectives of this research are i) to focus the mineral, chemical and petrographic compositions of the San Nicola stones, ii) the chemical and physical alteration processes affecting these materials, and iii) to establish the exactly provenance of the volcanic rocks. Furthermore, a comparative study between the rocks from the ancient quarries and those forming the structure of the church was performed. In the ancient quarries, where presumably a more advanced alteration occurs due to the vertical alteration gradient, different facies of the same volcanic lithology, characterized by macroscopical evidences of chemical-physical degradation degree, were sampled. Petrographic, geochemical (both major elements that the traces) and physical-mechanical features of the collected samples were determined to highlight the compositional differences (density, porosity, water-absorption kinetics, mechanical resistance) as a function of the different alteration degree. Moreover, chemical-mineralogical analysis of the sample surfaces from the church, was performed, to highlight possible presence and nature of secondary newly-formed phases (e.g., salt efflorescence). Several methodologies were applied to carry out physical-chemical and petrographic analysis: X-Ray fluorescence (XRF) and Inductively Coupled Mass Spectrometry (ICP-MS), X-Ray Diffractometry (XRD) for chemical and mineral composition; Optical and Scanning Electron Microscopy (SEM) for textures, mineral assemblages and microstructures studies; He-picnometry, water-absorption and mechanical

  18. Regulation of naturally occurring radioactive materials in Australia

    International Nuclear Information System (INIS)

    Jeffries, C.; Akber, R.; Johnston, A.; Cassels, B.

    2011-01-01

    In order to promote uniformity between jurisdictions, the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) has developed the National Directory for Radiation Protection, which is a regulatory framework that all Australian governments have agreed to adopt. There is a large and diverse range of industries involved in mining or mineral processing, and the production of fossil fuels in Australia. Enhanced levels of naturally occurring radionuclides can be associated with mineral extraction and processing, other industries (e.g. metal recycling) and some products (e.g. plasterboard). ARPANSA, in conjunction with industry and State regulators, has undertaken a review and assessment of naturally occurring radioactive material (NORM) management in Australian industries. This review has resulted in guidance on the management of NORM that will be included in the National Directory for Radiation Protection. The first NORM safety guide provides the framework for NORM management and addresses specific NORM issues in oil and gas production, bauxite, aluminium and phosphate industries. Over time further guidance material for other NORM-related industries will be developed. This presentation will provide an overview of the regulatory approach to managing NORM industries in Australia. (authors)

  19. Regulation of naturally occurring radioactive materials in Australia.

    Science.gov (United States)

    Jeffries, Cameron; Akber, Riaz; Johnston, Andrew; Cassels, Brad

    2011-07-01

    In order to promote uniformity between jurisdictions, the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) has developed the National Directory for Radiation Protection, which is a regulatory framework that all Australian governments have agreed to adopt. There is a large and diverse range of industries involved in mining or mineral processing, and the production of fossil fuels in Australia. Enhanced levels of naturally occurring radionuclides can be associated with mineral extraction and processing, other industries (e.g. metal recycling) and some products (e.g. plasterboard). ARPANSA, in conjunction with industry and State regulators, has undertaken a review and assessment of naturally occurring radioactive material (NORM) management in Australian industries. This review has resulted in guidance on the management of NORM that will be included in the National Directory for Radiation Protection. The first NORM safety guide provides the framework for NORM management and addresses specific NORM issues in oil and gas production, bauxite, aluminium and phosphate industries. Over time further guidance material for other NORM-related industries will be developed. This presentation will provide an overview of the regulatory approach to managing NORM industries in Australia.

  20. Altered affective response in marijuana smokers: an FMRI study.

    Science.gov (United States)

    Gruber, Staci A; Rogowska, Jadwiga; Yurgelun-Todd, Deborah A

    2009-11-01

    More than 94 million Americans have tried marijuana, and it remains the most widely used illicit drug in the nation. Investigations of the cognitive effects of marijuana report alterations in brain function during tasks requiring executive control, including inhibition and decision-making. Endogenous cannabinoids regulate a variety of emotional responses, including anxiety, mood control, and aggression; nevertheless, little is known about smokers' responses to affective stimuli. The anterior cingulate and amygdala play key roles in the inhibition of impulsive behavior and affective regulation, and studies using PET and fMRI have demonstrated changes within these regions in marijuana smokers. Given alterations in mood and perception often observed in smokers, we hypothesized altered fMRI patterns of response in 15 chronic heavy marijuana smokers relative to 15 non-marijuana smoking control subjects during the viewing of masked happy and fearful faces. Despite no between-group differences on clinical or demographic measures, smokers demonstrated a relative decrease in both anterior cingulate and amygdalar activity during masked affective stimuli compared to controls, who showed relative increases in activation within these regions during the viewing of masked faces. Findings indicate that chronic heavy marijuana smokers demonstrate altered activation of frontal and limbic systems while viewing masked faces, consistent with autoradiographic studies reporting high CB-1 receptor density in these regions. These data suggest differences in affective processing in chronic smokers, even when stimuli are presented below the level of conscious processing, and underscore the likelihood that marijuana smokers process emotional information differently from those who do not smoke, which may result in negative consequences.

  1. Alterations in polyadenylation and its implications for endocrine disease

    Directory of Open Access Journals (Sweden)

    Anders eRehfeld

    2013-05-01

    Full Text Available IntroductionPolyadenylation is the process in which the pre-mRNA is cleaved at the poly(A site and a poly(A tail is added - a process necessary for normal mRNA formation. Genes with multiple poly(A sites can undergo alternative polyadenylation, producing distinct mRNA isoforms with different 3’ untranslated regions (3’ UTRs and in some cases different coding regions. Two thirds of all human genes undergo alternative polyadenylation. The efficiency of the polyadenylation process regulates gene expression and alternative polyadenylation plays an important part in post-transcriptional regulation, as the 3’ UTR contains various cis-elements associated with post-transcriptional regulation, such as target sites for microRNAs and RNA-binding proteins.Implications of alterations in polyadenylation for endocrine diseaseAlterations in polyadenylation have been found to be causative of neonatal diabetes and IPEX (immune dysfunction, polyendocrinopathy, enteropathy, X-linked and to be associated with type I and II diabetes, pre-eclampsia, fragile X-associated premature ovarian insufficiency, ectopic Cushing syndrome and many cancer diseases, including several types of endocrine tumor diseases.PerspectivesRecent developments in high-throughput sequencing have made it possible to characterize polyadenylation genome-wide. Antisense elements inhibiting or enhancing specific poly(A site usage can induce desired alterations in polyadenylation, and thus hold the promise of new therapeutic approaches. SummaryThis review gives a detailed description of alterations in polyadenylation in endocrine disease, an overview of the current literature on polyadenylation and summarizes the clinical implications of the current state of research in this field.

  2. The plasma physics of plasma processing

    International Nuclear Information System (INIS)

    Shohet, L.

    1991-01-01

    Plasma processing is used for producing new materials with unusual and superior properties, for developing new chemical compounds and processes, for machining, and for altering and refining materials and surfaces. It has direct applications to semiconductor fabrication, materials synthesis, welding, lighting, polymers, anti-corrosion coatings, machine tools, metallurgy, electrical and electronics devices, hazardous waste removal, high performance ceramics, and many other items in both high-technology and the more traditional industries. Plasma processing takes on a wide variety of apparently different forms in industry, but the techniques share many common characteristics and problems. Control of the generation and flux of ions, electrons and free radicals in the plasma and their incidence on a surface is vital. Diagnostics, sensors, modeling techniques, and associated statistical methods are needed. However, without an in-depth understanding of the variety of phenomena taking place and their application to the industrial environment, advances in this technology, and its efficient use, will occur at a diminishing rate

  3. Morphologic alterations in normal and neoplastic tissues following hyperthermia treatment

    International Nuclear Information System (INIS)

    Badylak, S.F.; Babbs, C.F.

    1984-01-01

    The sequential morphologic alterations in normal skeletal muscle in rats, Walker 256 tumors in rats, and transmissible venereal tumors (TVT) in dogs following microwave-induced hyperthermia (43 0 C and 45 0 for 20 minutes) were studied by light and electron microscopy. Normal muscle and Walker 256 tumors showed vascular damage at 5 minutes post-heating (PH), followed by suppuration and thrombosis at 6 and 48 hours PH, and by regeneration and repair at 7 days PH. Endothelial damage and parenchymal degeneration were present 5 minutes PH. Progressive ischemic injury occurred for at least 48 hours PH. Two hyperthermia treatments, separated by a 30 or 60 minute cooling interval, were applied to rats implanted with Walker 256 tumors. Increased selective heating of tumor tissue versus surrounding normal tissue, and increased intratumoral temperatures were found during the second hyperthermia treatment. Canine TVTs were resistant to hyperthermia damage. These results characterized the sequential morphologic alterations following hyperthermia treatment and showed that: 1) vascular damage contributed to the immediate and latent cytotoxic effects of hyperthermia, 2) selective heating occurred in the neoplastic tissue disrupted by prior heat treatment, and 3) not all neoplasms are responsive to hyperthermia treatment

  4. Modelling of processes occurring in deep geological repository - development of new modules in the GoldSim environment

    International Nuclear Information System (INIS)

    Vopalka, D.; Lukin, D.; Vokal, A.

    2006-01-01

    Three new modules modelling the processes that occur in a deep geological repository have been prepared in the GoldSim computer code environment (using its Transport Module). These modules help to understand the role of selected parameters in the near-field region of the final repository and to prepare an own complex model of the repository behaviour. The source term module includes radioactive decay and ingrowth in the canister, first order degradation of fuel matrix, solubility limitation of the concentration of the studied nuclides, and diffusive migration through the surrounding bentonite layer controlled by the output boundary condition formulated with respect to the rate of water flow in the rock. The corrosion module describes corrosion of canisters made of carbon steel and transport of corrosion products in the near-field region. This module computes balance equations between dissolving species and species transported by diffusion and/or advection from the surface of a solid material. The diffusion module that includes also non-linear form of the interaction isotherm can be used for an evaluation of small-scale diffusion experiments. (author)

  5. Modelling of processes occurring in deep geological repository - Development of new modules in the GoldSim environment

    Science.gov (United States)

    Vopálka, D.; Lukin, D.; Vokál, A.

    2006-01-01

    Three new modules modelling the processes that occur in a deep geological repository have been prepared in the GoldSim computer code environment (using its Transport Module). These modules help to understand the role of selected parameters in the near-field region of the final repository and to prepare an own complex model of the repository behaviour. The source term module includes radioactive decay and ingrowth in the canister, first order degradation of fuel matrix, solubility limitation of the concentration of the studied nuclides, and diffusive migration through the surrounding bentonite layer controlled by the output boundary condition formulated with respect to the rate of water flow in the rock. The corrosion module describes corrosion of canisters made of carbon steel and transport of corrosion products in the near-field region. This module computes balance equations between dissolving species and species transported by diffusion and/or advection from the surface of a solid material. The diffusion module that includes also non-linear form of the interaction isotherm can be used for an evaluation of small-scale diffusion experiments.

  6. Mortar alteration: experimental study and ancient analogues

    International Nuclear Information System (INIS)

    Rassineux, Francois

    1987-01-01

    As the durability of cemented matrices is a matter of great importance in numerous domains, notably for the long term reliability of surface storages of radioactive wastes, the objective of this research thesis is to define mechanisms of evolution of cemented matrices when in contact with diluted aqueous solutions. The author notably studied the influence of the lixiviation mode on the evolution of two mortars having different compositions (pH, CO 2 pressure, system containment, and cement mineralogical nature appear to be the main governing parameters), the alteration (dissolution is the prevailing process in the interaction between cemented matrices and a diluted solution such as rain water), and ancient binders (archaeological binders containing mineral phases such as hydrated calcium silicates or hydro-grossulars). The obtained results lead to the definition of alteration mechanisms in modern cements, and highlight factors governing the durability of these materials when submitted to meteoric alteration [fr

  7. Endocrine modulation, inhibition of ovarian development and hepatic alterations in rainbow trout exposed to polluted river water

    Energy Technology Data Exchange (ETDEWEB)

    Vigano, Luigi, E-mail: vigano@irsa.cnr.i [Water Research Institute, National Council of Research, Brugherio, Milan (Italy); Benfenati, Emilio [Mario Negri Institute, Laboratory of Environmental Chemistry and Toxicology, Milan (Italy); Bottero, Sergio; Cevasco, Alessandra; Monteverde, Martino; Mandich, Alberta [Department of Environmental, Experimental and Applied Biology, University of Genoa, Genoa (Italy)

    2010-12-15

    Under laboratory conditions, female rainbow trout were exposed to graded concentrations of water from the River Lambro, a polluted tributary of the River Po, and to the effluent of a large wastewater treatment plant which flows into the River Lambro. In field exposures, trout were held in cages in the River Po upstream and downstream from the confluence of the River Lambro. After 10-day (laboratory) and 30-day (laboratory and field) exposures, trout were examined for several chemical, biochemical and histological endpoints. The results indicated that exposure to complex mixtures of chemicals, including estrogen receptor agonists, aryl-hydrocarbon receptor agonists, and probably antiandrogens, had occurred. Exposure altered the plasma levels of 17{beta}-estradiol and testosterone, and some treatments also enhanced the activity of hepatic ethoxyresorufin O-deethylase. Gonadal histology showed varying levels of degenerative processes characterised by oocyte atresia, haemorrhages, melano-macrophage centres (MMCs), and oogonia proliferation. Liver histology showed less severe effects. - This study examined the progression of hormonal and gonadal alterations in female trout exposed to river water from an area known to affect resident fish species.

  8. Endocrine modulation, inhibition of ovarian development and hepatic alterations in rainbow trout exposed to polluted river water

    International Nuclear Information System (INIS)

    Vigano, Luigi; Benfenati, Emilio; Bottero, Sergio; Cevasco, Alessandra; Monteverde, Martino; Mandich, Alberta

    2010-01-01

    Under laboratory conditions, female rainbow trout were exposed to graded concentrations of water from the River Lambro, a polluted tributary of the River Po, and to the effluent of a large wastewater treatment plant which flows into the River Lambro. In field exposures, trout were held in cages in the River Po upstream and downstream from the confluence of the River Lambro. After 10-day (laboratory) and 30-day (laboratory and field) exposures, trout were examined for several chemical, biochemical and histological endpoints. The results indicated that exposure to complex mixtures of chemicals, including estrogen receptor agonists, aryl-hydrocarbon receptor agonists, and probably antiandrogens, had occurred. Exposure altered the plasma levels of 17β-estradiol and testosterone, and some treatments also enhanced the activity of hepatic ethoxyresorufin O-deethylase. Gonadal histology showed varying levels of degenerative processes characterised by oocyte atresia, haemorrhages, melano-macrophage centres (MMCs), and oogonia proliferation. Liver histology showed less severe effects. - This study examined the progression of hormonal and gonadal alterations in female trout exposed to river water from an area known to affect resident fish species.

  9. Growth and alteration of uranium-rich microlite

    International Nuclear Information System (INIS)

    Giere, R.; Swope, R. J.; Buck, E. C.; Guggenheim, R.; Mathys, D.; Reusser, E.

    2000-01-01

    Uranium-rich microlite, a pyrochlore-group mineral, occurs in 440 Ma old lithium pegmatites of the Mozambique Belt in East Africa. Microlite exhibits a pronounced growth zoning, with a U-free core surrounded by a U-rich rim (UO 2 up to 17 wt.%). The core exhibits conjugate sets of straight cracks (cleavage planes) which provided pathways for a late-stage U-enriched pegmatitic fluid which interacted with the U-free microlite to produce a distinct U enrichment along the cracks and led to the formation of the U-rich rim. Following the stage of U incorporation into microlite, a second generation of hydrothermal fluids deposited mica along the cleavage planes. Subsequent to these two hydrothermal stages, the host rock was uplifted and subjected to intense low-temperature alteration during which Na, Ca and F were leached from the microlite crystals. This alteration also led to a hydration of microlite, but there is no evidence of U loss. These low-temperature alteration effects were only observed in the U-rich rim which is characterized by a large number of irregular cracks which are most probably the result of metamictization, as indicated by electron diffraction images and powder X-ray patterns. The pyrochlore-group minerals provide excellent natural analogues for pyrochlore-based nuclear waste forms, because samples of variable age and with high actinide contents are available

  10. Working memory and hearing aid processing: Literature findings, future directions, and clinical applications

    Directory of Open Access Journals (Sweden)

    Pamela eSouza

    2015-12-01

    Full Text Available Working memory—the ability to process and store information—has been identified as an important aspect of speech perception in difficult listening environments. Working memory can be envisioned as a limited-capacity system which is engaged when an input signal cannot be readily matched to a stored representation or template. This mismatch is expected to occur more frequently when the signal is degraded. Because working memory capacity varies among individuals, those with smaller capacity are expected to demonstrate poorer speech understanding when speech is degraded, such as in background noise. However, it is less clear whether (and how working memory should influence practical decisions, such as hearing treatment. Here, we consider the relationship between working memory capacity and response to specific hearing aid processing strategies. Three types of signal processing are considered, each of which will alter the acoustic signal: fast-acting wide-dynamic range compression, which smooths the amplitude envelope of the input signal; digital noise reduction, which may inadvertently remove speech signal components as it suppresses noise; and frequency compression, which alters the relationship between spectral peaks. For fast-acting wide-dynamic range compression, a growing body of data suggests that individuals with smaller working memory capacity may be more susceptible to such signal alterations, and may receive greater amplification benefit with low alteration processing. While the evidence for a relationship between wide-dynamic range compression and working memory appears robust, the effects of working memory on perceptual response to other forms of hearing aid signal processing are less clear cut. We conclude our review with a discussion of the opportunities (and challenges in translating information on individual working memory into clinical treatment, including clinically-feasible measures of working memory.

  11. Working Memory and Hearing Aid Processing: Literature Findings, Future Directions, and Clinical Applications.

    Science.gov (United States)

    Souza, Pamela; Arehart, Kathryn; Neher, Tobias

    2015-01-01

    Working memory-the ability to process and store information-has been identified as an important aspect of speech perception in difficult listening environments. Working memory can be envisioned as a limited-capacity system which is engaged when an input signal cannot be readily matched to a stored representation or template. This "mismatch" is expected to occur more frequently when the signal is degraded. Because working memory capacity varies among individuals, those with smaller capacity are expected to demonstrate poorer speech understanding when speech is degraded, such as in background noise. However, it is less clear whether (and how) working memory should influence practical decisions, such as hearing treatment. Here, we consider the relationship between working memory capacity and response to specific hearing aid processing strategies. Three types of signal processing are considered, each of which will alter the acoustic signal: fast-acting wide-dynamic range compression, which smooths the amplitude envelope of the input signal; digital noise reduction, which may inadvertently remove speech signal components as it suppresses noise; and frequency compression, which alters the relationship between spectral peaks. For fast-acting wide-dynamic range compression, a growing body of data suggests that individuals with smaller working memory capacity may be more susceptible to such signal alterations, and may receive greater amplification benefit with "low alteration" processing. While the evidence for a relationship between wide-dynamic range compression and working memory appears robust, the effects of working memory on perceptual response to other forms of hearing aid signal processing are less clear cut. We conclude our review with a discussion of the opportunities (and challenges) in translating information on individual working memory into clinical treatment, including clinically feasible measures of working memory.

  12. Alterations to the subchondral bone architecture during osteoarthritis : bone adaptation versus endochondral bone formation

    NARCIS (Netherlands)

    Cox, L.G.E.; Donkelaar, van C.C.; Rietbergen, van B.; Emans, P.J.; Ito, K.

    2013-01-01

    Objective Osteoarthritis (OA) is characterized by loss of cartilage and alterations in subchondral bone architecture. Changes in cartilage and bone tissue occur simultaneously and are spatially correlated, indicating that they are probably related. We investigated two hypotheses regarding this

  13. Behavioral correlates of cerebrospinal fluid amino acid and biogenic amine neurotransmitter alterations in dementia

    NARCIS (Netherlands)

    Vermeiren, Yannick; Le Bastard, Nathalie; Van Hemelrijck, An; Drinkenburg, Wilhelmus H.; Engelborghs, Sebastiaan; De Deyn, Peter P.

    Background: Behavioral and psychological signs and symptoms of dementia (BPSD) are a heterogeneous group of behavioral and psychiatric disturbances occurring in dementia patients of any etiology. Research suggests that altered activities of dopaminergic, serotonergic, (nor)adrenergic, as well as

  14. Effect of alteration processes on the distribution of radionuclides in uraniferous sedimentary rocks and their environmental impact, southwestern Sinai, Egypt

    International Nuclear Information System (INIS)

    El Aassy, I.E.; El Galy, M.M.; El Feky, M.G.; Ibrahim, E.M.; Nada, A.A.; Abd El Maksoud, T.M.; Talaat, S.M.

    2011-01-01

    The contents of natural radionuclides in various types of sedimentary rocks in Um Bogma Formation and base of El Hashash Formation were determined by gamma-ray spectrometry. Three types of lower Carboniferous sedimentary rocks were investigated; sandstone (El Hashash Formation), dolostone and argillaceous sediments (Um Bogma Formation). The alteration processes are dolomitization, dedolomitization, karstification and lateritization. The specific radioactivity of 238 U, 226 Ra, 232 Th and 40 K determined in different samples, indicate that 238 U and its decay products contribute primarily to the high natural radioactivity of rocks. The maximum concentration of 238 U reached up to 2129.36 ppm in argillaceous sediments. The average concentrations of determined radionuclides ( 238 U, 226 Ra, 232 Th and 40 K) are 8.34 ppm, 7.88 ppm, 4.68 ppm and 0.3%, respectively in sandstone. In dolostones the average concentrations are 418.69 ppm, 808.75 ppm, 3.14 ppm and 0.29%, respectively. For argillaceous sediments are 276.88 ppm, 419.49 ppm, 11.47 ppm and 0.93%, respectively. The 238 U/ 226 Ra ratio in sandstone ranges between 0.89 and 1.25, while in dolostones and argillaceous sediments are 0.27-2.63 and 0.27-1.83, respectively. These variations in the concentrations of radioelements and their ratios are due to the action of the alteration processes affected these different sedimentary rocks in different times. Environmentally, the Raeq in dolostones and argillaceous sediments exceeds the permitted limits, while in the sandstone samples; it is within the permissible levels. (author)

  15. Does altered protein metabolism interfere with postmortem degradation analysis for PMI estimation?

    Science.gov (United States)

    Zissler, A; Ehrenfellner, B; Foditsch, E E; Monticelli, F C; Pittner, S

    2018-03-02

    An accurate estimation of the postmortem interval (PMI) is a central aspect in forensic routine. Recently, a novel approach based on the analysis of postmortem muscle protein degradation has been proposed. However, a number of questions remain to be answered until sensible application of this method to a broad variety of forensic cases is possible. To evaluate whether altered in vivo protein metabolism interferes with postmortem degradation patterns, we conducted a comparative study. We developed a standardized animal degradation model in rats, and collected additional muscle samples from animals recovering from muscle injury and from rats with developed disuse muscle atrophy after induced spinal cord injury. All samples were analyzed by SDS-PAGE and Western blot, labeling well-characterized muscle proteins. Tropomyosin was found to be stable throughout the investigated PMI and no alterations were detected in regenerating and atrophic muscles. In contrast, significant predictable postmortem changes occurred in desmin and vinculin protein band patterns. While no significant deviations from native patterns were detected in at-death samples of disuse muscle atrophy, interestingly, samples of rats recovering from muscle injury revealed additional desmin and vinculin degradation bands that did not occur in this form in any of the examined postmortem samples regardless of PMI. It remains to be investigated whether in vivo-altered metabolism influences postmortem degradation kinetics or if such muscle samples undergo postmortem degradation in a regular fashion.

  16. Alteration and long-term behaviour of different types of innovative materials for long-lived radionuclides confinement; Alteration et comportement a long terme de differentes classes de materiaux innovants pour le confinement des radionucleides a vie longue

    Energy Technology Data Exchange (ETDEWEB)

    Leturcq, G

    1998-09-29

    The present work is an experimental study on alteration mechanisms of synthetic and natural materials: aluminosilicate glasses, glass ceramics and Ti, Zr or P based ceramics. It is a part of CEA's study program on the immobilization of long- lived radionuclides and deals with chemical processes which control dissolution of amorphous and crystallized solids. The different aluminosilicate glasses studied are altered according to a process of hydrolysis of the bonds between the glass network formers; the activation energy of this reaction is about 60 kJ/mol. Alteration rates of all the glasses decrease by four orders of magnitude when the reaction progress increases. Kinetic laws based on the deviation from the thermodynamic equilibrium between leachate and the fresh solid cannot explain these great decreases. Alteration layers in the reactional interface seem to control the alteration kinetics by providing a passivation process. The chemical durability of the glass ceramics (zirconolite and titanite) improves by a factor of ten in regard to the primary glasses which were obtained by thermal treatment. Zirconium-titanate ceramics are altered only slightly by water. The altered mass corresponds to a few atomic layers only. Steady stases are quickly observed. On the basis of thermodynamic calculations, they are not correlated with saturation between the leachate and primary zirconium-titanate phases. Alteration here also ceases due to the development of a passivating layer. Models aiming at studying the chemical durability of zirconium-titanate ceramics under conditions more representative of a clayey site of geological storage were carried out. The results of the interactions of these ceramics with clays, at 708 deg.C, show clearly that there is no modification of the process of alteration, compared to the simpler pure water systems. Thus, perovskite and zirconolite do not deteriorate under these conditions. (author)

  17. Geochemistry and genesis of APS minerals in advanced argillic alteration zone, northwest of Shir-Kuh, Yazd

    Directory of Open Access Journals (Sweden)

    Batool Taghipour

    2010-11-01

    Full Text Available Northwest of Shir-Kuh batholith, a number of leucocratic granitic and granodioritic plutons have intruded sedimentary hosts including shale-sandstone (Triassic-Jurassic and sandstone-conglomerate (Lower Cretaceous. Contact metamorphism and hydrothermal alterations are widespread. Late alteration assemblage mainly occurs in arkosic sandstones of Sangestan Formation and includes propylitic, quartz-sericitic, advanced argillic and silicific zones. Quartz-sericite zone is the most widespread. Advanced argillic alteration is characterized by the following assemblage: jarosite, alunite, turquoise, from the Al-Phosphate-Sulfate group (APS. Considering this mineral assemblage and probable interactions taking place between the minerals, a geochemical environment with high fO2 and low pH is thought to be prevailing at the time of alteration and formation of alunite, jarosite and turquoise.

  18. Alterations in the Emotional Regulation Process in Gambling Addiction: The Role of Anger and Alexithymia.

    Science.gov (United States)

    Maniaci, Giuseppe; Picone, Francesca; van Holst, Ruth J; Bolloni, Corinna; Scardina, Silvana; Cannizzaro, Carla

    2017-06-01

    This study aims at the assessment of alexithymia and anger levels in 100 treatment-seeking pathological gamblers compared with controls, who were matched for age, gender and education. Furthermore a positive correlation between alexithymia, anger and severity of gambling disorder and a relationship between gambling behaviour and anger after controlling for alexithymia, are investigated. Finally the role that gender plays in anger in pathological gamblers was also evaluated. Psychological assessment includes the South Oaks Gambling Screen, State-Trait Anger Expression Inventory-2 and the twenty-item Toronto Alexithymia Scale. Statistical analysis of the results shows a higher level of anger in pathological gamblers than in controls, together with alterations in emotional processing. Severity of gambling behaviour positively correlates with alexithymia scores, state-anger and trait-anger. Moreover, a significant contribution of anger in predicting gambling behaviour was suggested after controlling for alexithymia. In conclusion, anger and alexithymia must be regarded as relevant components of the assessment of pathological gamblers, in order to select the best therapeutical strategies to prevent self-defeating behaviours and to reduce drop-out from treatments.

  19. Cerebrospinal fluid space alterations in melancholic depression.

    Directory of Open Access Journals (Sweden)

    Esther Via

    Full Text Available Melancholic depression is a biologically homogeneous clinical entity in which structural brain alterations have been described. Interestingly, reports of structural alterations in melancholia include volume increases in Cerebro-Spinal Fluid (CSF spaces. However, there are no previous reports of CSF volume alterations using automated whole-brain voxel-wise approaches, as tissue classification algorithms have been traditionally regarded as less reliable for CSF segmentation. Here we aimed to assess CSF volumetric alterations in melancholic depression and their clinical correlates by means of a novel segmentation algorithm ('new segment', as implemented in the software Statistical Parametric Mapping-SPM8, incorporating specific features that may improve CSF segmentation. A three-dimensional Magnetic Resonance Image (MRI was obtained from seventy patients with melancholic depression and forty healthy control subjects. Although imaging data were pre-processed with the 'new segment' algorithm, in order to obtain a comparison with previous segmentation approaches, tissue segmentation was also performed with the 'unified segmentation' approach. Melancholic patients showed a CSF volume increase in the region of the left Sylvian fissure, and a CSF volume decrease in the subarachnoid spaces surrounding medial and lateral parietal cortices. Furthermore, CSF increases in the left Sylvian fissure were negatively correlated with the reduction percentage of depressive symptoms at discharge. None of these results were replicated with the 'unified segmentation' approach. By contrast, between-group differences in the left Sylvian fissure were replicated with a non-automated quantification of the CSF content of this region. Left Sylvian fissure alterations reported here are in agreement with previous findings from non-automated CSF assessments, and also with other reports of gray and white matter insular alterations in depressive samples using automated approaches

  20. DNA double-strand-break complexity levels and their possible contributions to the probability for error-prone processing and repair pathway choice.

    Science.gov (United States)

    Schipler, Agnes; Iliakis, George

    2013-09-01

    Although the DNA double-strand break (DSB) is defined as a rupture in the double-stranded DNA molecule that can occur without chemical modification in any of the constituent building blocks, it is recognized that this form is restricted to enzyme-induced DSBs. DSBs generated by physical or chemical agents can include at the break site a spectrum of base alterations (lesions). The nature and number of such chemical alterations define the complexity of the DSB and are considered putative determinants for repair pathway choice and the probability that errors will occur during this processing. As the pathways engaged in DSB processing show distinct and frequently inherent propensities for errors, pathway choice also defines the error-levels cells opt to accept. Here, we present a classification of DSBs on the basis of increasing complexity and discuss how complexity may affect processing, as well as how it may cause lethal or carcinogenic processing errors. By critically analyzing the characteristics of DSB repair pathways, we suggest that all repair pathways can in principle remove lesions clustering at the DSB but are likely to fail when they encounter clusters of DSBs that cause a local form of chromothripsis. In the same framework, we also analyze the rational of DSB repair pathway choice.

  1. Altered brain processing of decision-making in healthy first-degree biological relatives of suicide completers.

    Science.gov (United States)

    Ding, Y; Pereira, F; Hoehne, A; Beaulieu, M-M; Lepage, M; Turecki, G; Jollant, F

    2017-08-01

    Suicidal behavior is heritable, with the transmission of risk being related to the transmission of vulnerability traits. Previous studies suggest that risky decision-making may be an endophenotype of suicide. Here, we aimed at investigating brain processing of decision-making in relatives of suicide completers in order to shed light on heritable mechanisms of suicidal vulnerability. Seventeen healthy first-degree biological relatives of suicide completers with no personal history of suicidal behavior, 16 relatives of depressed patients without any personal or family history of suicidal behavior, and 19 healthy controls were recruited. Functional 3 T magnetic resonance imaging scans were acquired while participants underwent the Iowa Gambling Task, an economic decision-making test. Whole-brain analyses contrasting activations during risky vs safe choices were conducted with AFNI and FSL. Individuals with a family history of suicide in comparison to control groups showed altered contrasts in left medial orbitofrontal cortex, and right dorsomedial prefrontal cortex. This pattern was different from the neural basis of familial depression. Moreover, controls in comparison to relatives showed increased contrast in several regions including the post-central gyrus, posterior cingulate and parietal cortices, and cerebellum (culmen) in familial suicide; and inferior parietal, temporal, occipital, anteromedial and dorsolateral prefrontal cortices, and cerebellum (vermis) in familial depression. These findings most likely represent a complex combination of vulnerability and protective mechanisms in relatives. They also support a significant role for deficient risk processing, and ventral and dorsal prefrontal cortex functioning in the suicidal diathesis.

  2. Genetic Alterations and Their Clinical Implications in High-Recurrence Risk Papillary Thyroid Cancer.

    Science.gov (United States)

    Lee, Min-Young; Ku, Bo Mi; Kim, Hae Su; Lee, Ji Yun; Lim, Sung Hee; Sun, Jong-Mu; Lee, Se-Hoon; Park, Keunchil; Oh, Young Lyun; Hong, Mineui; Jeong, Han-Sin; Son, Young-Ik; Baek, Chung-Hwan; Ahn, Myung-Ju

    2017-10-01

    Papillary thyroid carcinomas (PTCs) frequently involve genetic alterations. The objective of this study was to investigate genetic alterations and further explore the relationships between these genetic alterations and clinicopathological characteristics in a high-recurrence risk (node positive, N1) PTC group. Tumor tissue blocks were obtained from 240 surgically resected patients with histologically confirmed stage III/IV (pT3/4 or N1) PTCs. We screened gene fusions using NanoString's nCounter technology and mutational analysis was performed by direct DNA sequencing. Data describing the clinicopathological characteristics and clinical courses were retrospectively collected. Of the 240 PTC patients, 207 (86.3%) had at least one genetic alteration, including BRAF mutation in 190 patients (79.2%), PIK3CA mutation in 25 patients (10.4%), NTRK1/3 fusion in six patients (2.5%), and RET fusion in 24 patients (10.0%). Concomitant presence of more than two genetic alterations was seen in 36 patients (15%). PTCs harboring BRAF mutation were associated with RET wild-type expression (p=0.001). RET fusion genes have been found to occur with significantly higher frequency in N1b stage patients (p=0.003) or groups of patients aged 45 years or older (p=0.031); however, no significant correlation was found between other genetic alterations. There was no trend toward favorable recurrence-free survival or overall survival among patients lacking genetic alterations. In the selected high-recurrence risk PTC group, most patients had more than one genetic alteration. However, these known alterations could not entirely account for clinicopathological features of high-recurrence risk PTC.

  3. Aging induced endoplasmic reticulum stress alters sleep and sleep homeostasis.

    Science.gov (United States)

    Brown, Marishka K; Chan, May T; Zimmerman, John E; Pack, Allan I; Jackson, Nicholas E; Naidoo, Nirinjini

    2014-06-01

    Alterations in the quality, quantity, and architecture of baseline and recovery sleep have been shown to occur during aging. Sleep deprivation induces endoplasmic reticular (ER) stress and upregulates a protective signaling pathway termed the unfolded protein response. The effectiveness of the adaptive unfolded protein response is diminished by age. Previously, we showed that endogenous chaperone levels altered recovery sleep in Drosophila melanogaster. We now report that acute administration of the chemical chaperone sodium 4-phenylbutyrate (PBA) reduces ER stress and ameliorates age-associated sleep changes in Drosophila. PBA consolidates both baseline and recovery sleep in aging flies. The behavioral modifications of PBA are linked to its suppression of ER stress. PBA decreased splicing of X-box binding protein 1 and upregulation of phosphorylated elongation initiation factor 2 α, in flies that were subjected to sleep deprivation. We also demonstrate that directly activating ER stress in young flies fragments baseline sleep and alters recovery sleep. Alleviating prolonged or sustained ER stress during aging contributes to sleep consolidation and improves recovery sleep or sleep debt discharge. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Isotope geochemistry of hydrothermal alteration in East of Esfahan, Central Iran

    Science.gov (United States)

    Taghipour, Sedigheh; Taghipour, Batoul

    2010-05-01

    In the Cenozoic magmatic belt of Central Iran, the Eocene volcanics and pyroclastics from the East of Esfahan underwent extensive hydrothermal alteration. The Eocene volcanics composed mostly of andesite lava and tuffs have been altered. The survey area is laterally zoned from an inner quartz-sericite alteration zone to an outer propylitic zone. Quartz-sericite alteration is predominant (>95%), but smaller zones of alunite-jarosite and silicified zones are present and superimposed onto a quartz-sericite alteration. In the quartz-sericite zone all altered rocks are light grayish to whitish in color and porphyritic with aphanitic groundmass. Concentrations of alunite and jarosite veinlets and stockworks are dispersed irregularly in this zone. Alunite and jarosite occur also as coatings on fractured rocks. All types of alunite occurrences are brick-red, cream, white and buff in colors, while jarosite is brown to rusty in colors. To verify, chemical composition of alunite and jarosite were identified by X-ray diffraction in mineral assemblages. Major alteration zones show inclusions of propylite, quartz sericite, advanced argillic and silicified zones. These alunites are mainly porcelaneous and their compositions show a solid solution between alunite and jarosite. In alteration zones, the mineral assemblage is characterized by alunite-jarosite + quartz + sericite + alkali feldspars + chlorite ± turquoise ± barite ± iron oxides. There are numerous alunite and jarosite occurrences, mainly as veinlets, in parts of the advanced argillic zone. Alunite δ18O and δ D values range from -1.76 to 8.81‰ and from -52.86 to -129.26‰ respectively. Field observations, mineralogical evidence and results from light element stable isotope data (δ18O, δ D and δ34S); indicate that in this area alunitization is supergene in origin.

  5. Prostate Cancer: Epigenetic Alterations, Risk Factors, and Therapy

    Directory of Open Access Journals (Sweden)

    Mankgopo M. Kgatle

    2016-01-01

    Full Text Available Prostate cancer (PCa is the most prevalent urological cancer that affects aging men in South Africa, and mechanisms underlying prostate tumorigenesis remain elusive. Research advancements in the field of PCa and epigenetics have allowed for the identification of specific alterations that occur beyond genetics but are still critically important in the pathogenesis of tumorigenesis. Anomalous epigenetic changes associated with PCa include histone modifications, DNA methylation, and noncoding miRNA. These mechanisms regulate and silence hundreds of target genes including some which are key components of cellular signalling pathways that, when perturbed, promote tumorigenesis. Elucidation of mechanisms underlying epigenetic alterations and the manner in which these mechanisms interact in regulating gene transcription in PCa are an unmet necessity that may lead to novel chemotherapeutic approaches. This will, therefore, aid in developing combination therapies that will target multiple epigenetic pathways, which can be used in conjunction with the current conventional PCa treatment.

  6. Alteration and long-term behaviour of different types of innovative materials for long-lived radionuclides confinement

    International Nuclear Information System (INIS)

    Leturcq, G.

    1998-01-01

    The present work is an experimental study on alteration mechanisms of synthetic and natural materials: aluminosilicate glasses, glass ceramics and Ti, Zr or P based ceramics. It is a part of CEA's study program on the immobilization of long- lived radionuclides and deals with chemical processes which control dissolution of amorphous and crystallized solids. The different aluminosilicate glasses studied are altered according to a process of hydrolysis of the bonds between the glass network formers; the activation energy of this reaction is about 60 kJ/mol. Alteration rates of all the glasses decrease by four orders of magnitude when the reaction progress increases. Kinetic laws based on the deviation from the thermodynamic equilibrium between leachate and the fresh solid cannot explain these great decreases. Alteration layers in the reactional interface seem to control the alteration kinetics by providing a passivation process. The chemical durability of the glass ceramics (zirconolite and titanite) improves by a factor of ten in regard to the primary glasses which were obtained by thermal treatment. Zirconium-titanate ceramics are altered only slightly by water. The altered mass corresponds to a few atomic layers only. Steady stases are quickly observed. On the basis of thermodynamic calculations, they are not correlated with saturation between the leachate and primary zirconium-titanate phases. Alteration here also ceases due to the development of a passivating layer. Models aiming at studying the chemical durability of zirconium-titanate ceramics under conditions more representative of a clayey site of geological storage were carried out. The results of the interactions of these ceramics with clays, at 708 deg.C, show clearly that there is no modification of the process of alteration, compared to the simpler pure water systems. Thus, perovskite and zirconolite do not deteriorate under these conditions. (author)

  7. Reactive-brittle dynamics in peridotite alteration

    Science.gov (United States)

    Evans, O.; Spiegelman, M. W.; Kelemen, P. B.

    2017-12-01

    The interactions between reactive fluids and brittle solids are critical in Earth dynamics. Implications of such processes are wide-ranging: from earthquake physics to geologic carbon sequestration and the cycling of fluids and volatiles through subduction zones. Peridotite alteration is a common feature in many of these processes, which - despite its obvious importance - is relatively poorly understood from a geodynamical perspective. In particular, alteration reactions are thought to be self-limiting in nature, contradicting observations of rocks that have undergone 100% hydration/carbonation. One potential explanation of this observation is the mechanism of "reaction-driven cracking": that volume changes associated with these reactions are large enough to fracture the surrounding rock, leading to a positive feedback where new reactive surfaces are exposed and fluid pathways are created. The purpose of this study is to investigate the relative roles of reaction, elastic stresses and surface tension in alteration reactions. In this regard we derive a system of equations describing reactive fluid flow in an elastically deformable porous media, and explore them via a combination of analytic and numerical solutions. Using this model we show that the final stress state of a dry peridotite that has undergone reaction depends strongly on the rates of reaction versus fluid transport: significant fluid flow driven by pressure and/or surface tension gradients implies higher fractions of serpentinization, leaving behind a highly stressed residuum of partially reacted material. Using a model set-up that mimics a cylindrical triaxial apparatus we predict that the resulting stresses would lead to tensile failure and the generation of radially oriented cracks.

  8. Natural Transformation of Campylobacter jejuni Occurs Beyond Limits of Growth

    Science.gov (United States)

    Vegge, Christina S.; Brøndsted, Lone; Ligowska-Marzęta, Małgorzata; Ingmer, Hanne

    2012-01-01

    Campylobacter jejuni is a human bacterial pathogen. While poultry is considered to be a major source of food borne campylobacteriosis, C. jejuni is frequently found in the external environment, and water is another well-known source of human infections. Natural transformation is considered to be one of the main mechanisms for mediating transfer of genetic material and evolution of the organism. Given the diverse habitats of C. jejuni we set out to examine how environmental conditions and physiological processes affect natural transformation of C. jejuni. We show that the efficiency of transformation is correlated to the growth conditions, but more importantly that transformation occurs at growth-restrictive conditions as well as in the late stationary phase; hence revealing that growth per se is not required for C. jejuni to be competent. Yet, natural transformation of C. jejuni is an energy dependent process, that occurs in the absence of transcription but requires an active translational machinery. Moreover, we show the ATP dependent ClpP protease to be important for transformation, which possibly could be associated with reduced protein glycosylation in the ClpP mutant. In contrast, competence of C. jejuni was neither found to be involved in DNA repair following DNA damage nor to provide a growth benefit. Kinetic studies revealed that several transformation events occur per cell cycle indicating that natural transformation of C. jejuni is a highly efficient process. Thus, our findings suggest that horizontal gene transfer by natural transformation takes place in various habitats occupied by C. jejuni. PMID:23049803

  9. Chlorite in alteration zone of uranium deposits No.201, No.325 and No.706

    Energy Technology Data Exchange (ETDEWEB)

    Jianguo, He; Jiashu, Rong; Yuxian, Mao; Jianzhong, Li; Changliang, Wang; Mingyue, Feng [Beijing Research Inst. of Uranium Geology, Beijing (China); Minqiang, Zhu; Minghui, Rao [East China Inst. of T echnology, Fuzhou (China)

    2008-09-15

    According to mineralogical examination and electron microprobe data analysis, post-biotite chlorite and spheluritic chlorite are two forms of chlorites in the alteration zone of granite-type uranium deposits No.325 and No.706. As post-biotite chlorite is substituted for spheluritic chlorite, during the substitution, some Fe are released and Mg replace in, which results in the further hematization in rock. This is probably one of the reasons that red color occurs in sodium metasomatic alteration zone. The chlorites in uranium deposits No.201 and No.325 are brunsvigite and ripidolite. Most of the chlorites in uranium deposit No.706 are pycnochlorite and diabantite, while a few are brunsvigites. A new finding shows that the chlorite variety is determined mainly by {Sigma}FeO and MgO ratio of primary rock and is independent of alteration characteristic (acidic alteration or alkalic alteration). The proportion of Mg hydroxyl and Al hydroxyl in the unit-cell of chlorite may cause spectrum difference of diagnostic absorptive valley position and depth at 2259-2262 nm and 2348-2359 nm. (authors)

  10. Altered Cyclosporine Absorption in a Patient with Ulcerative Colitis, Sclerosing Cholangitis and Pancreatic Insufficiency

    Directory of Open Access Journals (Sweden)

    Mark G Swain

    1991-01-01

    Full Text Available Pancreatic insufficiency leading to altered cyclosporine absorption is reported in a 37-year-old man with ulcerative colitis and sclerosing cholangitis. Asymptomatic chronic pancreatitis occurs frequently in patients with ulcerative colitis, and even more commonly when there is coexistent sclerosing cholangitis. However, pancreatic insufficiency has been documented in only one patient previously with ulcerative colitis and sclerosing cholangitis. Pancreatic function testing can help to identify the complex etiology of malabsorption in these patients and is recommended in patients when liver transplantation is contemplated, as pancreatic insufficiency may alter the absorption of cyclosporine.

  11. Risk-associated health disorders occuring in junior schoolchildren who attend schools with higher stress and intensity of educational process

    Directory of Open Access Journals (Sweden)

    N.V. Zaitseva

    2017-03-01

    Full Text Available We performed comparative sanitary-hygienic assessment of regime, stress and intensity of educational process in different educational establishments, a comprehensive secondary school and an innovative educational establishment - lyceum. We detected that studying regime tended to be tight, classes were longer and more intense than in an ordinary school, and educational process involved considerable intellectual, sensory and emotional loads for children; such loads reached "1st category intense" level. Schoolchildren attending lyceums are also busy with additional educational programs and it significantly increases length of total educational load on them. By the end of a school year 20% of lyceum pupils suffer from sympathoadrenal system overstress and it doesn't only determine emotional tonus level in children but also leads to disorders in concentration and decision-making speed, lower reading speed and articulation, slower motor reactions. 15% of lyceum pupils have higher activity of autonomous nervous system and lower adaptation of cardiovascular system to psycho emotional and physical loads. Lyceum pupils also run 2.5 times higher risk of chronic nervous system diseases evolvement than school children attending ordinary schools. Autonomous nervous system disorders, posture disorders and nutrition disorders are predominant nosologic pathology forms in lyceum pupils as they occur in them 1.6-2.9 times more frequent than in schoolchildren of the same age who attend an ordinary comprehensive school. We detected direct correlation between higher intellectual and emotional components of educational process, and total educational intensity as well, and frequency of autonomous system disorders and musculoskeletal system diseases in pupils.

  12. Two Cases of Cerebral Air Embolism That Occurred during Esophageal Ballooning and Endoscopic Retrograde Cholangiopancreatography

    Directory of Open Access Journals (Sweden)

    Suyeon Park

    2016-03-01

    Full Text Available Cerebral air embolism is an extremely rare complication of endoscopic procedure and often life threatening. We present two cases of cerebral infarction due to air embolization caused by an endoscopic intervention. The first case occurred during esophageal balloon dilatation for the treatment of a stricture of an anastomosis site in a 59-year-old man and the second case occurred during endoscopic papillary balloon dilatation in a 69-year-old man who had distal common bile duct stones. After the procedure, cardiopulmonary instability and altered mental status were observed in both patients, and cerebral air embolism was diagnosed in both cases. Hyperbaric oxygen therapy was started in the first case, and high FiO2 therapy was applied in the second case. Although this complication is rare, patient outcomes can be improved if physicians are aware of this potential complication, and immediately begin proper management.

  13. Analysis of the planned post-mining landscape of MIBRAG's open-cast mines with regard to a possible environmental impact of alteration processes in mixed dumps; Analyse der geplanten Bergbaufolgelandschaft der MIBRAG-Tagebaue in Bezug auf moegliche Umweltauswirkungen durch die Folgen von Stoffumwandlungsprozessen in Kippenmischboeden

    Energy Technology Data Exchange (ETDEWEB)

    Jolas, Peter; Hofmann, Berthold [Mitteldeutsche Braunkohlengesellschaft mbH, Theissen (Germany)

    2009-03-15

    In recent years increasing knowledge has been gained with regard to hydro- and geochemical alteration processes in overburden dumps and their impact on groundwater quality in lignite mining and reclamation operations associated with post-mining landscapes in Germany. The questions of how alteration processes affect the environment and which opportunities exist to actively influence the dumping process in order to counteract any possible negative impact of the alteration processes, have been investigated at the MIBRAG mines. Investigations focus on the impact caused by oxidation of sulfur containing minerals. (orig.)

  14. Nucleolar proteins change in altered gravity

    Science.gov (United States)

    Sobol, M. A.; Kordyum, E. L.; Gonzalez-Camacho, F.; Medina, F. J.

    Discovery of gravisensitivity of cells no specified to gravity perception focused continuous attention on an elucidation of mechanisms involved in altered gravity effects at the different levels of cellular organization A nucleolus is the nuclear domain in which the major portion of ribosome biogenesis takes place This is a basic process for cell vitality beginning with the transcription of rDNA followed by processing newly synthesized pre-rRNA molecules A wide range of nucleolar proteins plays a highly significant role in all stages of biosynthesis of ribosomes Different steps of ribosome biogenesis should respond to various external factors affecting generally the cell metabolism Nevertheless a nucleolus remains not enough studied under the influence of altered environmental conditions For this reason we studied root apices from 2-day old Lepidium sativum seedlings germinated and grown under slow horizontal clinorotation and stationary conditions in darkness The extraction of cell nuclei followed by sequential fractionation of nuclear proteins according to their solubility in buffers of increasing ionic strength was carried out This procedure gave rise to 5 distinct fractions We analyzed nuclear subproteomes of the most soluble fraction called S2 It is actually a functionally significant fraction consisting of ribonucleoproteins actively engaged in pre-rRNA synthesis and processing 2D-electrophoresis of S2 fraction proteins was carried out The gels were silver stained and stained gels were scanned and analyzed

  15. Alteration and geochemical zoning in Bodie Bluff, Bodie mining district, eastern California

    Science.gov (United States)

    Herrera, P.A.; Closs, L.G.; Silberman, M.L.

    1993-01-01

    Banded, epithermal quartz-adularia veins have produced about 1.5 million ounces of gold and 7 million ounces of silver from the Bodie mining district, eastern California. The veins cut dacitic lava flows, pyroclastic rocks and intrusions. Sinter boulders occur in a graben structure at the top of Bodie Bluff and fragments of sinter and mineralized quartz veins occur in hydrothermal breccias nearby. Explosive venting evidently was part of the evolution of the ore-forming geothermal systems which, at one time, must had reached the paleosurface. Previous reconnaissance studies at Bodie Bluff suggested that the geometry of alteration mineral assemblages and distribution of some of the major and trace elements throughout the system correspond to those predicted by models of hot-spring, volcanic rock hosted precious metal deposits (Silberman, 1982; Silberman and Berger, 1985). The current study was undertaken to evaluate these sugestions further. About 500 samples of quartz veins and altered rocks, including sinter, collected over a vertical extent of 200 meters within Bodie Bluff were petrographically examined and chemically analyzed for trace elements by emission spectrographic and atomic absorption methods. Sixty-five samples were analyzed for major elements by X-ray fluorescence methods. The results of these analyses showed that, in general, alteration mineral assemblage and vertical geochemical zoning patterns follow those predicted for hot-spring deposits, but that geochemical zoning patterns for sinter and quartz veins (siliceous deposits), and altered wall rocks are not always similar. The predicted depth-concentration patterns for some elements, notably Au, Ag, Hg, and Tl in quartz veins, and Hg, As and Ag in wall rocks were not as expected, or were perturbed by the main ore producing zone. For both quartz veins and altered wall rocks, the main ore zone had elevated metal contents. Increased concentration of many of these elements could indicate proximity to this

  16. Preliminary study on features of mineralogical zoning of epigenetic alteration at sandstone-type uranium deposit, Dongsheng area, Ordos basin

    International Nuclear Information System (INIS)

    Xiao Xinjian; Li Ziying; Chen Anping

    2004-01-01

    Sandstone-type uranium deposits located in Dongsheng area, northern Ordos basin, occur in Zhiluo Formation, Middle Jurassic. The Zhiluo Formation is divided into two members. The lower member is further divided into two submembers. The lower submember is dominantly composed of grey sandstone being the ore-hosting horizon; the upper submember consists of grey-green sandstone and mudstone. The upper member of Zhiluo Formation is made of mottled medium-fine grained sandstone and mudstone. Through the microscopic observation and study on sandstones of Zhiluo Formation, authors have established a vertical zonation of epigenetic alteration (from the top to the bottom): the limonitization + clayization + carbonation in the mottled fine-grained sandstone of the upper member of Zhiluo Formation; the green alteration (II) (mainly the chloritization of biotite, as well as the chloritization and epidotization of feldspar) + clayization + carbonation in the grey-green sandstone of the upper submember of the lower member of Zhiluo Formation; and the green alteration (I) (mainly the epidotization of feldspar) + carbonation in grey, grey-white sandstone of the lower submember. The epigenetic alteration basically occurs in grey-green sandstone. The sandstone shows grey-green color because it contains much green biotite (not chlorite). The epigenetic alteration in sandstone layer is closely associated with the uranium ore-formation

  17. Drought occurence

    Science.gov (United States)

    John W. Coulston

    2007-01-01

    Why Is Drought Important? Drought is an important forest disturbance that occurs regularly in the Western United States and irregularly in the Eastern United States (Dale and others 2001). Moderate drought stress tends to slow plant growth while severedrought stress can also reduce photosynthesis (Kareiva and others 1993). Drought can also interact with...

  18. Antagonist effects of calcium on borosilicate glass alteration

    Energy Technology Data Exchange (ETDEWEB)

    Mercado-Depierre, S. [CEA Marcoule, DTCD SPDE LCLT, 30207 Bagnols sur Cèze (France); Angeli, F., E-mail: frederic.angeli@cea.fr [CEA Marcoule, DTCD SPDE LCLT, 30207 Bagnols sur Cèze (France); Frizon, F. [CEA Marcoule, DTCD SECM LP2C, 30207 Bagnols sur Cèze (France); Gin, S. [CEA Marcoule, DTCD SPDE LCLT, 30207 Bagnols sur Cèze (France)

    2013-10-15

    Graphical abstract: Display Omitted -- Highlights: •Kinetic study of glass alteration is investigated in calcium-enriched solutions. •New insights into silicon–calcium interactions in glass/cement systems are proposed. •Glass alteration is controlled by pH, Ca concentration and reaction progress. •Evidence of antagonist effects according to the importance of these parameters. -- Abstract: Numerous studies have been conducted on glass and cement durability in contact with water, but very little work to date has focused directly on interactions between the two materials. These interactions are mostly controlled by silicon–calcium reactivity. However, the physical and chemical processes involved remain insufficiently understood to predict the evolution of coupled glass–cement systems used in several industrial applications. Results are reported from borosilicate glass alteration in calcium-rich solutions. Our data show that four distinct behaviors can be expected according to the relative importance of three key parameters: the pH, the reaction progress (short- or long-term alteration) and the calcium concentration. Glass alteration is thus controlled by specific mechanisms depending on the solution chemistry: calcium complexation at the glass surface, precipitation of calcium silicate hydrates (C–S–H) or calcium incorporation in the altered layer. These findings highlight the impact of silicon–calcium interactions on glass durability and open the way for a better understanding of glass–cement mixing in civil engineering applications as well as in nuclear waste storage.

  19. Antagonist effects of calcium on borosilicate glass alteration

    International Nuclear Information System (INIS)

    Mercado-Depierre, S.; Angeli, F.; Frizon, F.; Gin, S.

    2013-01-01

    Graphical abstract: Display Omitted -- Highlights: •Kinetic study of glass alteration is investigated in calcium-enriched solutions. •New insights into silicon–calcium interactions in glass/cement systems are proposed. •Glass alteration is controlled by pH, Ca concentration and reaction progress. •Evidence of antagonist effects according to the importance of these parameters. -- Abstract: Numerous studies have been conducted on glass and cement durability in contact with water, but very little work to date has focused directly on interactions between the two materials. These interactions are mostly controlled by silicon–calcium reactivity. However, the physical and chemical processes involved remain insufficiently understood to predict the evolution of coupled glass–cement systems used in several industrial applications. Results are reported from borosilicate glass alteration in calcium-rich solutions. Our data show that four distinct behaviors can be expected according to the relative importance of three key parameters: the pH, the reaction progress (short- or long-term alteration) and the calcium concentration. Glass alteration is thus controlled by specific mechanisms depending on the solution chemistry: calcium complexation at the glass surface, precipitation of calcium silicate hydrates (C–S–H) or calcium incorporation in the altered layer. These findings highlight the impact of silicon–calcium interactions on glass durability and open the way for a better understanding of glass–cement mixing in civil engineering applications as well as in nuclear waste storage

  20. Membrane Peeling-Induced Retinal Alterations on Intraoperative OCT in Vitreomacular Interface Disorders From the PIONEER Study.

    Science.gov (United States)

    Ehlers, Justis P; Han, Jaehong; Petkovsek, Daniel; Kaiser, Peter K; Singh, Rishi P; Srivastava, Sunil K

    2015-11-01

    To assess retinal architectural alterations that occur following membrane peeling procedures and the impact of peel technique on these alterations utilizing intraoperative optical coherence tomography (iOCT). This is a subanalysis of the prospective PIONEER iOCT study of eyes undergoing a membrane peeling for a vitreomacular interface (VMI) disorder. Intraoperative scanning was performed with a microscope-mounted OCT system. Macroarchitectural alterations (e.g., full-thickness retinal elevations) and microarchitectural alterations (e.g., relative layer thickness alterations) were analyzed. Video/iOCT correlation was performed to identify instrument-tissue manipulations resulting in macroarchitectural alterations. One hundred sixty-three eyes were included in the macroarchitectural analysis. Instrumentation utilized for membrane peeling included forceps alone for 73 eyes (45%), combined diamond-dusted membrane scraper (DDMS) and forceps for 87 eyes (53%), and other techniques in three eyes (2%). Focal retinal elevations were identified in 45 of 163 eyes (28%). Video/iOCT correlation identified 69% of alterations involved forceps compared to 26% due to DDMS. Sixteen percent of retinal alterations persisted 1 month following surgery. The microarchitectural analysis included 134 eyes. Immediately following membrane peeling, there was a significant increase in the ellipsoid zone to retinal pigment epithelium height (+20%, P peeling for VMI conditions. Differences in surgical instruments may impact these architectural alterations.

  1. Cell surface glycan alterations in epithelial mesenchymal transition process of Huh7 hepatocellular carcinoma cell.

    Directory of Open Access Journals (Sweden)

    Shan Li

    Full Text Available BACKGROUND AND OBJECTIVE: Due to recurrence and metastasis, the mortality of Hepatocellular carcinoma (HCC is high. It is well known that the epithelial mesenchymal transition (EMT and glycan of cell surface glycoproteins play pivotal roles in tumor metastasis. The goal of this study was to identify HCC metastasis related differential glycan pattern and their enzymatic basis using a HGF induced EMT model. METHODOLOGY: HGF was used to induce HCC EMT model. Lectin microarray was used to detect the expression of cell surface glycan and the difference was validated by lectin blot and fluorescence cell lectin-immunochemistry. The mRNA expression levels of glycotransferases were determined by qRT-PCR. RESULTS: After HGF treatment, the Huh7 cell lost epithelial characteristics and obtained mesenchymal markers. These changes demonstrated that HGF could induce a typical cell model of EMT. Lectin microarray analysis identified a decreased affinity in seven lectins ACL, BPL, JAC, MPL, PHA-E, SNA, and SBA to the glycan of cell surface glycoproteins. This implied that glycan containing T/Tn-antigen, NA2 and bisecting GlcNAc, Siaα2-6Gal/GalNAc, terminal α or βGalNAc structures were reduced. The binding ability of thirteen lectins, AAL, LCA, LTL, ConA, NML, NPL, DBA, HAL, PTL II, WFL, ECL, GSL II and PHA-L to glycan were elevated, and a definite indication that glycan containing terminal αFuc and ± Sia-Le, core fucose, α-man, gal-β(α GalNAc, β1,6 GlcNAc branching and tetraantennary complex oligosaccharides structures were increased. These results were further validated by lectin blot and fluorescence cell lectin-immunochemistry. Furthermore, the mRNA expression level of Mgat3 decreased while that of Mgat5, FucT8 and β3GalT5 increased. Therefore, cell surface glycan alterations in the EMT process may coincide with the expression of glycosyltransferase. CONCLUSIONS: The findings of this study systematically clarify the alterations of cell surface

  2. Radiation protection and the naturally occurring radioactive materials (NORM)

    International Nuclear Information System (INIS)

    Paschoa, A.S.; MacDowell, P.

    1996-01-01

    There are many industries dealing with naturally occurring radioactive materials (NORM), some of them without knowing that their industrial processes and/or their regular wastes involve radioactivity. However, an increasing number of industries that produce NORM wastes are being sued, wherever there is a legal framework to do so. In particular, NORM wastes produced for a long time by the oil industry became foci of legal battles in the United States and elsewhere. The ripple effect of these judicial battles will influence the decision making processes of NORM wastes producing industries, mostly because of the costs incurred by remedial and preventive actions concerning NORM contamination. The regulation of NORM will occur sooner or later, and such actions may become mandatory. A foreseeable consequence of such regulation is a change in attitude concerning the sources and materials associated with NORM. Among those industries likely to be affected one can mention: niobium; rare earth processing; oil production; phosphate; uranium mining and milling; zircon; water treatment; and waste water treatment. The paper will briefly review data on exempt concentration activities, as suggested by the basic safety standards based on realistic environmental and dosimetric models. These activity concentrations are compared with those found in a number of extractive industries, and may be used to establish derived limits from a pre-established dose limit. (author)

  3. Covalent DNA-protein crosslinking occurs after hyperthermia and radiation

    International Nuclear Information System (INIS)

    Cress, A.E.; Bowden, G.T.

    1983-01-01

    Covalent DNA-protein crosslinks occur in exponentially growing mouse leukemia cells (L1210) after exposure to ionizing radiation. The amount of DNA-protein crosslinks as measured by a filter binding assay is dose dependent upon X irradiation. Although hyperthermia and radiation in combination are synergistic with respect to cell lethality, the combination does not result in an increase of DNA-protein crosslinks when assayed immediately following treatments. Hyperthermia (43 degrees C/15 min) given prior to radiation does not alter the radiation dose dependency of the amount of initial crosslinking. In addition, the amount of DNA-protein crosslinking produced by heat plus radiation is independent of the length of heating the cells at 43 degrees C. The DNA-protein crosslinks produced by 50-Gy X ray alone are removed after 2 hr at 37 degrees C. However, if hyperthermia (43 degrees C/15 min) is given prior to 100-Gy X ray, the removal of DNA-protein crosslinks is delayed until 4.0 hr after radiation. Phospho-serine and phospho-threonine bonds are not produced with either radiation or the combination of hyperthermia plus radiation as judged by the resistance of the bonds to guanidine hydrochloride. However, hyperthermia plus radiation causes an increase in phosphate to nitrogen type bonding. These results show that radiation alone causes covalent DNA-protein crosslinks. Hyperthermia in combination with radiation does not increase the total amount of the crosslinks but delays the removal of the crosslinks and alters the distribution of the types of chemical bonding. These data suggest that the synergistic action on hyperthermia with radiation is more related to the rate of removal and the type of chemical bonding involved in the covalent DNA-protein crosslinks rather than the amount of DNA-protein crosslinks

  4. On the in situ aqueous alteration of soils on Mars

    Science.gov (United States)

    Amundson, Ronald; Ewing, Stephanie; Dietrich, William; Sutter, Brad; Owen, Justine; Chadwick, Oliver; Nishiizumi, Kunihiko; Walvoord, Michelle; McKay, Christopher

    2008-08-01

    Early (>3 Gy) wetter climate conditions on Mars have been proposed, and it is thus likely that pedogenic processes have occurred there at some point in the past. Soil and rock chemistry of the Martian landing sites were evaluated to test the hypothesis that in situ aqueous alteration and downward movement of solutes have been among the processes that have transformed these portions of the Mars regolith. A geochemical mass balance shows that Martian soils at three landing sites have lost significant quantities of major rock-forming elements and have gained elements that are likely present as soluble ions. The loss of elements is interpreted to have occurred during an earlier stage(s) of weathering that may have been accompanied by the downward transport of weathering products, and the salts are interpreted to be emplaced later in a drier Mars history. Chemical differences exist among the sites, indicating regional differences in soil composition. Shallow soil profile excavations at Gusev crater are consistent with late stage downward migration of salts, implying the presence of small amounts of liquid water even in relatively recent Martian history. While the mechanisms for chemical weathering and salt additions on Mars remain unclear, the soil chemistry appears to record a decline in leaching efficiency. A deep sedimentary exposure at Endurance crater contains complex depth profiles of SO 4, Cl, and Br, trends generally consistent with downward aqueous transport accompanied by drying. While no model for the origin of Martian soils can be fully constrained with the currently available data, a pedogenic origin is consistent with observed Martian geology and geochemistry, and provides a testable hypothesis that can be evaluated with present and future data from the Mars surface.

  5. Prenatal cocaine exposure alters alpha2 receptor expression in adolescent rats

    Directory of Open Access Journals (Sweden)

    Silvers Janelle M

    2006-04-01

    Full Text Available Abstract Background Prenatal cocaine exposure produces attentional deficits which to persist through early childhood. Given the role of norepinephrine (NE in attentional processes, we examined the forebrain NE systems from prenatal cocaine exposed rats. Cocaine was administered during pregnancy via the clinically relevant intravenous route of administration. Specifically, we measured α2-adrenergic receptor (α2-AR density in adolescent (35-days-old rats, using [3H]RX821002 (5 nM. Results Sex-specific alterations of α2-AR were found in the hippocampus and amygdala of the cocaine-exposed animals, as well as an upregulation of α2-AR in parietal cortex. Conclusion These data suggest that prenatal cocaine exposure results in a persistent alteration in forebrain NE systems as indicated by alterations in receptor density. These neurochemical changes may underlie behavioral abnormalities observed in offspring attentional processes following prenatal exposure to cocaine.

  6. Eczematous Dermatitis Occurring on a Café-au-Lait Spot Long after Laser Radiation.

    Science.gov (United States)

    Mihara, Motoyuki

    2013-05-01

    A 40-year-old woman presented with an itchy erythematosquamous change of a café-au-lait spot in her face. The onset of this change occurred just after her relocation. The café-au-lait spot had been irradiated by laser approximately 20 years ago. Clinically, there was a coin-sized erythema with a slight scale on the pigmented lesion in the left lateral orbital region. Histopathologically, the lesion demonstrated both spongiotic dermatitis and interface dermatitis together with lymphohistiocytic cell infiltration, in addition to moderate acanthosis and elongation of rete ridges with slight basal hyperpigmentation. From these clinical and histopathological findings, the lesion was diagnosed as eczematous dermatitis occurring on the café-au-lait spot after laser radiation. Another interesting histopathological finding was that some parts of a lobule of the sebaceous gland were occupied exclusively by degenerative atrophic sebocytes. From the viewpoint of pathogenesis, the eczematous dermatitis of this patient could have been an accompanying feature of a neurogenic inflammation occurring on the café-au-lait spot after laser radiation, and the atrophic change of a part of the sebaceous lobule might have been induced by a morphogenetic alteration of certain germinative cells of the sebaceous lobule due to laser radiation.

  7. Links between contaminant hotspots in low flow estuarine systems and altered sediment biogeochemical processes

    Science.gov (United States)

    Sutherland, Michael D.; Dafforn, Katherine A.; Scanes, Peter; Potts, Jaimie; Simpson, Stuart L.; Sim, Vivian X. Y.; Johnston, Emma L.

    2017-11-01

    The urbanisation of coastal zones is a major threat to the health of global estuaries and has been linked to increased contamination (e.g. metals) and excess organic matter. Urban stormwater networks collect and funnel contaminants into waterways at point sources (e.g. stormdrains). Under dry, low flow conditions, these stormwater contaminants can accumulate in sediments over time and result in modifications to benthic sediment biogeochemical processes. To quantify these processes, this field study measured differences in benthic metabolism (CR, GPP, NEM) and sediment-water nutrient fluxes (NH3, NOx, PO4) associated with stormdrains (0 m, 200 m and 1000 m away) and increased water-retention (embayments vs channels). Significant changes to benthic metabolism were detected with distance from stormdrains, and with differences in water-retention rates, above natural spatial and temporal variation. Oxygen consumption was ∼50% higher at stormdrains (0 m) compared to 1000 m away and >70% higher at stormdrains (0 m) located in embayments compared to channels. Oxygen production also appeared to decrease with distance from stormdrains in embayments, but patterns were variable. These changes to benthic metabolism were of a magnitude expected to influence benthic nutrient cycling, but NH3, NOx and PO4 fluxes were generally low, and highly spatially and temporally variable. Overall, metal (Cu) contamination explained most of the variation in sediment biogeochemical processes between embayments and channels, while sediment grain size explained differences in fluxes with distance from stormdrains. Importantly, although there was evidence of increased productivity associated with stormdrains, we also detected evidence of early hypoxia suggesting that systems with legacy stormwater contaminants exist on a tipping point. Future work should investigate changes to sediment processes after a major rainfall event, when large and sudden inputs of potentially toxic contaminants occur

  8. Hypergravity-induced altered behavior in Drosophila

    Science.gov (United States)

    Hosamani, Ravikumar; Wan, Judy; Marcu, Oana; Bhattacharya, Sharmila

    2012-07-01

    Microgravity and mechanical stress are important factors of the spaceflight environment, and affect astronaut health and behavior. Structural, functional, and behavioral mechanisms of all cells and organisms are adapted to Earth's gravitational force, 1G, while altered gravity can pose challenges to their adaptability to this new environment. On ground, hypergravity paradigms have been used to predict and complement studies on microgravity. Even small changes that take place at a molecular and genetic level during altered gravity may result in changes in phenotypic behavior. Drosophila provides a robust and simple, yet very reliable model system to understand the complexity of hypergravity-induced altered behavior, due to availability of a plethora of genetic tools. Locomotor behavior is a sensitive parameter that reflects the array of molecular adaptive mechanisms recruited during exposure to altered gravity. Thus, understanding the genetic basis of this behavior in a hypergravity environment could potentially extend our understanding of mechanisms of adaptation in microgravity. In our laboratory we are trying to dissect out the cellular and molecular mechanisms underlying hypergravity-induced oxidative stress, and its potential consequences on behavioral alterations by using Drosophila as a model system. In the present study, we employed pan-neuronal and mushroom body specific knock-down adult flies by using Gal4/UAS system to express inverted repeat transgenes (RNAi) to monitor and quantify the hypergravity-induced behavior in Drosophila. We established that acute hypergravity (3G for 60 min) causes a significant and robust decrease in the locomotor behavior in adult Drosophila, and that this change is dependent on genes related to Parkinson's disease, such as DJ-1α , DJ-1β , and parkin. In addition, we also showed that anatomically the control of this behavior is significantly processed in the mushroom body region of the fly brain. This work links a molecular

  9. Epigenetic Alterations in Alzheimer’s Disease

    Science.gov (United States)

    Sanchez-Mut, Jose V.; Gräff, Johannes

    2015-01-01

    Alzheimer’s disease (AD) is the major cause of dementia in Western societies. It progresses asymptomatically during decades before being belatedly diagnosed when therapeutic strategies have become unviable. Although several genetic alterations have been associated with AD, the vast majority of AD cases do not show strong genetic underpinnings and are thus considered a consequence of non-genetic factors. Epigenetic mechanisms allow for the integration of long-lasting non-genetic inputs on specific genetic backgrounds, and recently, a growing number of epigenetic alterations in AD have been described. For instance, an accumulation of dysregulated epigenetic mechanisms in aging, the predominant risk factor of AD, might facilitate the onset of the disease. Likewise, mutations in several enzymes of the epigenetic machinery have been associated with neurodegenerative processes that are altered in AD such as impaired learning and memory formation. Genome-wide and locus-specific epigenetic alterations have also been reported, and several epigenetically dysregulated genes validated by independent groups. From these studies, a picture emerges of AD as being associated with DNA hypermethylation and histone deacetylation, suggesting a general repressed chromatin state and epigenetically reduced plasticity in AD. Here we review these recent findings and discuss several technical and methodological considerations that are imperative for their correct interpretation. We also pay particular focus on potential implementations and theoretical frameworks that we expect will help to better direct future studies aimed to unravel the epigenetic participation in AD. PMID:26734709

  10. A Polymorphism in the Processing Body Component Ge-1 Controls Resistance to a Naturally Occurring Rhabdovirus in Drosophila.

    Directory of Open Access Journals (Sweden)

    Chuan Cao

    2016-01-01

    Full Text Available Hosts encounter an ever-changing array of pathogens, so there is continual selection for novel ways to resist infection. A powerful way to understand how hosts evolve resistance is to identify the genes that cause variation in susceptibility to infection. Using high-resolution genetic mapping we have identified a naturally occurring polymorphism in a gene called Ge-1 that makes Drosophila melanogaster highly resistant to its natural pathogen Drosophila melanogaster sigma virus (DMelSV. By modifying the sequence of the gene in transgenic flies, we identified a 26 amino acid deletion in the serine-rich linker region of Ge-1 that is causing the resistance. Knocking down the expression of the susceptible allele leads to a decrease in viral titre in infected flies, indicating that Ge-1 is an existing restriction factor whose antiviral effects have been increased by the deletion. Ge-1 plays a central role in RNA degradation and the formation of processing bodies (P bodies. A key effector in antiviral immunity, the RNAi induced silencing complex (RISC, localises to P bodies, but we found that Ge-1-based resistance is not dependent on the small interfering RNA (siRNA pathway. However, we found that Decapping protein 1 (DCP1 protects flies against sigma virus. This protein interacts with Ge-1 and commits mRNA for degradation by removing the 5' cap, suggesting that resistance may rely on this RNA degradation pathway. The serine-rich linker domain of Ge-1 has experienced strong selection during the evolution of Drosophila, suggesting that this gene may be under long-term selection by viruses. These findings demonstrate that studying naturally occurring polymorphisms that increase resistance to infections enables us to identify novel forms of antiviral defence, and support a pattern of major effect polymorphisms controlling resistance to viruses in Drosophila.

  11. Basic perceptual changes that alter meaning and neural correlates of recognition memory

    Directory of Open Access Journals (Sweden)

    Chuanji eGao

    2015-02-01

    Full Text Available It is difficult to pinpoint the border between perceptual and conceptual processing, despite their treatment as distinct entities in many studies of recognition memory. For instance, alteration of simple perceptual characteristics of a stimulus can radically change meaning, such as the color of bread changing from white to green. We sought to better understand the role of perceptual and conceptual processing in memory by identifying the effects of changing a basic perceptual feature (color on behavioral and neural correlates of memory in circumstances when this change would be expected to either change the meaning of a stimulus or to have no effect on meaning (i.e., to influence conceptual processing or not. Abstract visual shapes (squiggles were colorized during study and presented during test in either the same color or a different color. Those squiggles that subjects found to resemble meaningful objects supported behavioral measures of conceptual priming, whereas meaningless squiggles did not. Further, changing color from study to test had a selective effect on behavioral correlates of priming for meaningful squiggles, indicating that color change altered conceptual processing. During a recognition memory test, color change altered event-related brain potential correlates of memory for meaningful squiggles but not for meaningless squiggles. Specifically, color change reduced the amplitude of frontally distributed N400 potentials (FN400, indicating that these potentials indicated conceptual processing during recognition memory that was sensitive to color change. In contrast, color change had no effect on FN400 correlates of recognition for meaningless squiggles, which were overall smaller in amplitude than for meaningful squiggles (further indicating that these potentials signal conceptual processing during recognition. Thus, merely changing the color of abstract visual shapes can alter their meaning, changing behavioral and neural correlates

  12. Wet, Carbonaceous Asteroids: Altering Minerals, Changing Amino Acids

    Science.gov (United States)

    Taylor, G. J.

    2011-04-01

    Many carbonaceous chondrites contain alteration products from water-rock interactions at low temperature and organic compounds. A fascinating fact known for decades is the presence in some of them of an assortment of organic compounds, including amino acids, sometimes called the building blocks of life. Murchison and other CM carbonaceous chondrites contain hundreds of amino acids. Early measurements indicated that the amino acids in carbonaceous chondrites had equal proportions of L- and D-structures, a situation called racemic. This was in sharp contrast to life on Earth, which heavily favors L- forms. However, beginning in 1997, John Cronin and Sandra Pizzarello (Arizona State University) found L- excesses in isovaline and several other amino acids in the Murchison carbonaceous chondrite. In 2009, Daniel Glavin and Jason Dworkin (Astrobiology Analytical Lab, Goddard Space Flight Center) reported the first independent confirmation of L-isovaline excesses in Murchison using a different analytical technique than employed by Cronin and Pizzarello. Inspired by this work, Daniel Glavin, Michael Callahan, Jason Dworkin, and Jamie Elsila (Astrobiology Analytical Lab, Goddard Space Flight Center), have done an extensive study of the abundance and symmetry of amino acids in carbonaceous chondrites that experienced a range of alteration by water in their parent asteroids. The results show that amino acids are more abundant in the less altered meteorites, implying that aqueous processing changes the mix of amino acids. They also confirmed the enrichment in L-structures of some amino acids, especially isovaline, confirming earlier work. The authors suggest that aqueously-altered planetesimals might have seeded the early Earth with nonracemic amino acids, perhaps explaining why life from microorganisms to people use only L- forms to make proteins. The initial imbalance caused by non-biologic processes in wet asteroids might have been amplified by life on Earth. Alternatively

  13. Ablation and chemical alteration of cosmic dust particles during entry into the earth`s atmosphere

    Digital Repository Service at National Institute of Oceanography (India)

    Rudraswami, N.G.; ShyamPrasad, M.; Dey, S.; Plane, J.M.C.; Feng, W.; Carrillo-Sanchez, J.D.; Fernandes, D.

    Most dust-sized cosmic particles undergo ablation and chemical alteration during atmospheric entry, which alters their original properties. A comprehensive understanding of this process is essential in order to decipher their pre...

  14. The Effect of Aqueous Alteration in Antarctic Carbonaceous Chondrites from Comparative ICP-MS Bulk Chemistry

    Science.gov (United States)

    Alonso-Azcarate, J.; Trigo-Rodriguez, J. M.; Moyano-Cambero, C. E.; Zolensky, M.

    2014-01-01

    Terrestrial ages of Antarctic carbonaceous chondrites (CC) indicate that these meteorites have been preserved in or on ice for, at least, tens of thousands of years. Due to the porous structure of these chondrites formed by the aggregation of silicate-rich chondrules, refractory inclusions, metal grains, and fine-grained matrix materials, the effect of pervasive terrestrial water is relevant. Our community defends that pristine CC matrices are representing samples of scarcely processed protoplanetary disk materials as they contain stellar grains, but they might also trace parent body processes. It is important to study the effects of terrestrial aqueous alteration in promoting bulk chemistry changes, and creating distinctive alteration minerals. Particularly because it is thought that aqueous alteration has particularly played a key role in some CC groups in modifying primordial bulk chemistry, and homogenizing the isotopic content of fine-grained matrix materials. Fortunately, the mineralogy produced by parent-body and terrestrial aqueous alteration processes is distinctive. With the goal to learn more about terrestrial alteration in Antarctica we are obtaining reflectance spectra of CCs, but also performing ICP-MS bulk chemistry of the different CC groups. A direct comparison with the mean bulk elemental composition of recovered falls might inform us on the effects of terrestrial alteration in finds. With such a goal, in the current work we have analyzed some members representative of CO and CM chondrite groups.

  15. Petrography and Mineral Chemistry of Magmatic and Hydrothermal Biotite in Porphyry Copper-Gold Deposits: A Tool for Understanding Mineralizing Fluid Compositional Changes During Alteration Processes

    Directory of Open Access Journals (Sweden)

    Arifudin Idrus

    2018-01-01

    Full Text Available DOI: 10.17014/ijog.5.1.47-64This study aims to understand the petrography and chemistry of both magmatic and hydrothermal biotites in porphyry copper-gold deposits, and to evaluate the fluid compositional changes during alteration processes. A total of 206 biotite grains from selected rock samples taken from the Batu Hijau porphyry Cu-Au deposit was analyzed. Detailed petrography and biotite chemistry analysis were performed on thin sections and polished thin sections, respectively, representing various rocks and alteration types. A JEOL JXA-8900R electron microprobe analyzer (EMPA was used for the chemistry analysis. The biotite is texturally divided into magmatic and hydrothermal types. Ti, Fe, and F contents can be used to distinguish the two biotite types chemically. Some oxide and halogen contents of biotite from various rocks and alteration types demonstrate a systematic variation in chemical composition. Biotite halogen chemistry shows a systematic increase in log (XCl/XOH and decrease in log (XF/XOH values from biotite (potassic through chlorite-sericite (intermediate argillic to actinolite (inner propylitic zones. The y-intercepts on the log (XCl/XOH vs. XMg and log (XF/XOH vs. XFe plotted for biotite from potassic and intermediate argillic zones are similar or slightly different. In contrast, the y-intercepts on the log (XCl/XOH vs. XMg and log (XF/XOH vs. XFe plotted for biotite from inner propylitic zone display different values in comparison to the two alteration zones. Halogen (F,Cl fugacity ratios in biotite show a similar pattern: in the potassic and intermediate argillic zones they show little variation, whereas in the inner propylitic zone they are distinctly different. These features suggest the hydrothermal fluid composition remained fairly constant in the inner part of the deposit during the potassic and intermediate argillic alteration events, but changed significantly towards the outer part affected by inner propylitic

  16. Hydrothermal alteration of a rhyolitic hyaloclastite from Ponza Island, Italy

    Science.gov (United States)

    Ylagan, Robert F.; Altaner, Stephen P.; Pozzuoli, Antonio

    1996-12-01

    silicic zone, and were possibly as high as 300 °C for the sericitic zone. The four zones occur as linear bands that increase in intensity north of the bentonite mine at Cala dell'Acqua. The alteration zones have two orientations and may be structurally controlled by E-W- and NE-SW-trending faulting which is consistent with the dominant structural trends of the Pontine archipelago. Finally, hydrothermal alteration most likely involved seawater based on the geologic evolution of Ponza.

  17. Sex differences in the clinical characteristics and brain gray matter volume alterations in unmedicated patients with major depressive disorder.

    Science.gov (United States)

    Yang, Xiao; Peng, Zugui; Ma, Xiaojuan; Meng, Yajing; Li, Mingli; Zhang, Jian; Song, Xiuliu; Liu, Ye; Fan, Huanhuan; Zhao, Liansheng; Deng, Wei; Li, Tao; Ma, Xiaohong

    2017-05-30

    This study was to explore the sex differences in clinical characteristics and brain gray matter volume (GMV) alterations in 29 male patients with major depressive disorder (MDDm), 53 female patients with MDD (MDDf), and in 29 male and 53 female matched healthy controls. Maps of GMV were constructed using magnetic resonance imaging data and compared between groups. We evaluated clinical symptoms using the Hamilton Rating Scale for Depression and obtained a total score and five syndrome scores. A two-factor ANCOVA model was specified using SPM8, with sex and diagnosis as the between-subject factors. We found that: (1) significant GMV increase in the left cerebellum and GMV reduction in the bilateral middle temporal gyrus and left ventral medial prefrontal gyrus occurred selectively in male patients, while the GMV reduction in the left lingual gyrus and dorsal medial prefrontal gyrus occurred selectively in female patients; (2) MDDf may have experienced more severe sleep disturbance than MDDm; and (3) the severity of sleep symptom could be predicted by the sex specific brain structural alterations in depressions. These findings suggest that sex specific anatomical alterations existed in MDD, and these alterations were associated with the clinical symptoms.

  18. Non-additive costs and interactions alter the competitive dynamics of co-occurring ecologically distinct plasmids.

    Science.gov (United States)

    Morton, Elise R; Platt, Thomas G; Fuqua, Clay; Bever, James D

    2014-03-22

    Plasmids play an important role in shaping bacterial evolution and adaptation to heterogeneous environments. As modular genetic elements that are often conjugative, the selective pressures that act on plasmid-borne genes are distinct from those that act on the chromosome. Many bacteria are co-infected by multiple plasmids that impart niche-specific phenotypes. Thus, in addition to host-plasmid dynamics, interactions between co-infecting plasmids are likely to be important drivers of plasmid population dynamics, evolution and ecology. Agrobacterium tumefaciens is a facultative plant pathogen that commonly harbours two distinct megaplasmids. Virulence depends on the presence of the tumour-inducing (Ti) plasmid, with benefits that are primarily restricted to the disease environment. Here, we demonstrate that a second megaplasmid, the At plasmid, confers a competitive advantage in the rhizosphere. To assess the individual and interactive costs of these plasmids, we generated four isogenic derivatives: plasmidless, pAt only, pTi only and pAtpTi, and performed pairwise competitions under carbon-limiting conditions. These studies reveal a low cost to the virulence plasmid when outside of the disease environment, and a strikingly high cost to the At plasmid. In addition, the costs of pAt and pTi in the same host were significantly lower than predicted based on single plasmid costs, signifying the first demonstration of non-additivity between naturally occurring co-resident plasmids. Based on these empirically demonstrated costs and benefits, we developed a resource-consumer model to generate predictions about the frequencies of these genotypes in relevant environments, showing that non-additivity between co-residing plasmids allows for their stable coexistence across environments.

  19. Genistein exposure inhibits growth and alters steroidogenesis in adult mouse antral follicles

    International Nuclear Information System (INIS)

    Patel, Shreya; Peretz, Jackye; Pan, Yuan-Xiang; Helferich, William G.; Flaws, Jodi A.

    2016-01-01

    Genistein is a naturally occurring isoflavone phytoestrogen commonly found in plant products such as soybeans, lentils, and chickpeas. Genistein, like other phytoestrogens, has the potential to mimic, enhance, or impair the estradiol biosynthesis pathway, thereby potentially altering ovarian follicle growth. Previous studies have inconsistently indicated that genistein exposure may alter granulosa cell proliferation and hormone production, but no studies have examined the effects of genistein on intact antral follicles. Thus, this study was designed to test the hypothesis that genistein exposure inhibits follicle growth and steroidogenesis in intact antral follicles. To test this hypothesis, antral follicles isolated from CD-1 mice were cultured with vehicle (dimethyl sulfoxide; DMSO) or genistein (6.0 and 36 μM) for 18–96 h. Every 24 h, follicle diameters were measured to assess growth. At the end of each culture period, the media were pooled to measure hormone levels, and the cultured follicles were collected to measure expression of cell cycle regulators and steroidogenic enzymes. The results indicate that genistein (36 μM) inhibits growth of mouse antral follicles. Additionally, genistein (6.0 and 36 μM) increases progesterone, testosterone, and dehydroepiandrosterone (DHEA) levels, but decreases estrone and estradiol levels. The results also indicate that genistein alters the expression of steroidogenic enzymes at 24, 72 and 96 h, and the expression of cell cycle regulators at 18 h. These data indicate that genistein exposure inhibits antral follicle growth by inhibiting the cell cycle, alters sex steroid hormone levels, and dysregulates steroidogenic enzymes in cultured mouse antral follicles. - Highlights: • Genistein exposure inhibits antral follicle growth. • Genistein exposure alters expression of cell cycle regulators. • Genistein exposure alters sex steroid hormones. • Genistein exposure alters expression of steroidogenic enzymes.

  20. Genistein exposure inhibits growth and alters steroidogenesis in adult mouse antral follicles

    Energy Technology Data Exchange (ETDEWEB)

    Patel, Shreya, E-mail: Shreya.patel214@gmail.com [Department of Comparative Biosciences, University of Illinois, 2001 S. Lincoln Ave, Urbana, IL 61802 (United States); Peretz, Jackye, E-mail: Jackye.peretz@gmail.com [Department of Comparative Biosciences, University of Illinois, 2001 S. Lincoln Ave, Urbana, IL 61802 (United States); Pan, Yuan-Xiang, E-mail: yxpan@illinois.edu [Department of Food Science and Human Nutrition, University of Illinois, 905 S. Goodwin, Urbana, IL 61801 (United States); Helferich, William G., E-mail: helferic@illinois.edu [Department of Food Science and Human Nutrition, University of Illinois, 905 S. Goodwin, Urbana, IL 61801 (United States); Flaws, Jodi A., E-mail: jflaws@illinois.edu [Department of Comparative Biosciences, University of Illinois, 2001 S. Lincoln Ave, Urbana, IL 61802 (United States)

    2016-02-15

    Genistein is a naturally occurring isoflavone phytoestrogen commonly found in plant products such as soybeans, lentils, and chickpeas. Genistein, like other phytoestrogens, has the potential to mimic, enhance, or impair the estradiol biosynthesis pathway, thereby potentially altering ovarian follicle growth. Previous studies have inconsistently indicated that genistein exposure may alter granulosa cell proliferation and hormone production, but no studies have examined the effects of genistein on intact antral follicles. Thus, this study was designed to test the hypothesis that genistein exposure inhibits follicle growth and steroidogenesis in intact antral follicles. To test this hypothesis, antral follicles isolated from CD-1 mice were cultured with vehicle (dimethyl sulfoxide; DMSO) or genistein (6.0 and 36 μM) for 18–96 h. Every 24 h, follicle diameters were measured to assess growth. At the end of each culture period, the media were pooled to measure hormone levels, and the cultured follicles were collected to measure expression of cell cycle regulators and steroidogenic enzymes. The results indicate that genistein (36 μM) inhibits growth of mouse antral follicles. Additionally, genistein (6.0 and 36 μM) increases progesterone, testosterone, and dehydroepiandrosterone (DHEA) levels, but decreases estrone and estradiol levels. The results also indicate that genistein alters the expression of steroidogenic enzymes at 24, 72 and 96 h, and the expression of cell cycle regulators at 18 h. These data indicate that genistein exposure inhibits antral follicle growth by inhibiting the cell cycle, alters sex steroid hormone levels, and dysregulates steroidogenic enzymes in cultured mouse antral follicles. - Highlights: • Genistein exposure inhibits antral follicle growth. • Genistein exposure alters expression of cell cycle regulators. • Genistein exposure alters sex steroid hormones. • Genistein exposure alters expression of steroidogenic enzymes.

  1. Altered Topology in Information Processing of a Narrated Story in Older Adults with Mild Cognitive Impairment.

    Science.gov (United States)

    Yogev-Seligmann, Galit; Oren, Noga; Ash, Elissa L; Hendler, Talma; Giladi, Nir; Lerner, Yulia

    2016-05-03

    The ability to store, integrate, and manipulate information declines with aging. These changes occur earlier, faster, and to a greater degree as a result of neurodegeneration. One of the most common and early characteristics of cognitive decline is difficulty with comprehension of information. The neural mechanisms underlying this breakdown of information processing are poorly understood. Using functional MRI and natural stimuli (e.g., stories), we mapped the neural mechanisms by which the human brain accumulates and processes information with increasing duration and complexity in participants with amnestic mild cognitive impairment (aMCI) and healthy older adults. To explore the mechanisms of information processing, we measured the reliability of brain responses elicited by listening to different versions of a narrated story created by segmenting the story into words, sentences, and paragraphs and then scrambling the segments. Comparing healthy older adults and participants with aMCI revealed that in both groups, all types of stimuli similarly recruited primary auditory areas. However, prominent differences between groups were found at the level of processing long and complex stimuli. In healthy older adults, parietal and frontal regions demonstrated highly synchronized responses in both the paragraph and full story conditions, as has been previously reported in young adults. Participants with aMCI, however, exhibited a robust functional shift of long time scale processing to the pre- and post-central sulci. Our results suggest that participants with aMCI experienced a functional shift of higher order auditory information processing, possibly reflecting a functional response to concurrent or impending neuronal or synaptic loss. This observation might assist in understanding mechanisms of cognitive decline in aMCI.

  2. Factors that Alter Body Fat, Body Mass, and Fat-Free Mass in Pediatric Obesity.

    Science.gov (United States)

    LeMura, Linda M.; Maziekas, Michael T.

    2002-01-01

    Investigated the effects of exercise programs on changes in body mass, fat-free mass, and body fat in obese children and adolescents. Research review indicated that exercise effectively helped reduce children's and adolescents' body composition variables. The most favorable body alterations occurred with low- intensity, long-duration exercise;…

  3. Mineralogical, micromorphological and geochemical transformations in the initial steps of the weathering process of charnockite from the Caparaó Range, southeastern Brazil

    Science.gov (United States)

    Soares, Caroline Cibele Vieira; Varajão, Angélica Fortes Drummond Chicarino; Varajão, César Augusto Chicarino; Boulangé, Bruno

    2014-12-01

    X-ray diffraction (XRD), X-ray Fluorescence (XRF), optical microscopy, Scanning Electron Microscopy coupled with Energy Dispersive Spectrometry (SEM-EDS) and Electron Probe micro-analyser (EPMA) and Wavelength-Dispersive Spectroscopy (WDS) were conducted on charnockite from the Caparaó Suite and its alteration cortex to determine the mineralogical, micromorphological and geochemical transformations resulting from the weathering process. The hydrolysis of the charnockite occurred in different stages, in accordance with the order of stability of the minerals with respect to weathering: andesine/orthopyroxene, pargasite and alkali feldspar. The rock modifications had begun with the formation of a layer of incipient alteration due to the percolation of weathering solutions first in the pressure relief fractures and then in cleavage and mineral edges. The iron exuded from ferromagnesian minerals precipitated in the intermineral and intramineral discontinuities. The layer of incipient alteration evolves into an inner cortex where the plagioclase changes into gibbsite by direct alitisation, the ferromagnesian minerals initiate the formation of goethitic boxworks with kaolinitic cores, and the alkali feldspar initiates indirect transformation into gibbsite, forming an intermediate phase of illite and kaolinite. In the outer cortex, mostly traces of alkali feldspar remain, and they are surrounded by goethite and gibbsite as alteromorphics, characterising the formation of the isalteritic horizon that occurs along the slope and explains the bauxitization process at the Caparaó Range, SE Brazil.

  4. Anticipation increases tactile stimulus processing in the ipsilateral primary somatosensory cortex.

    Science.gov (United States)

    van Ede, Freek; de Lange, Floris P; Maris, Eric

    2014-10-01

    Stimulus anticipation improves perception. To account for this improvement, we investigated how stimulus processing is altered by anticipation. In contrast to a large body of previous work, we employed a demanding perceptual task and investigated sensory responses that occur beyond early evoked activity in contralateral primary sensory areas: Stimulus-induced modulations of neural oscillations. For this, we recorded magnetoencephalography in 19 humans while they performed a cued tactile identification task involving the identification of either a proximal or a distal stimulation on the fingertips. We varied the cue-target interval between 0 and 1000 ms such that tactile targets occurred at various degrees of anticipation. This allowed us to investigate the influence of anticipation on stimulus processing in a parametric fashion. We observed that anticipation increases the stimulus-induced response (suppression of beta-band oscillations) originating from the ipsilateral primary somatosensory cortex. This occurs in the period in which the tactile memory trace is analyzed and is correlated with the anticipation-induced improvement in tactile perception. We propose that this ipsilateral response indicates distributed processing across bilateral primary sensory cortices, of which the extent increases with anticipation. This constitutes a new and potentially important mechanism contributing to perception and its improvement following anticipation. © The Author 2013. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  5. Altered Mucin and Glycoprotein Expression in Dry Eye Disease.

    Science.gov (United States)

    Stephens, Denise N; McNamara, Nancy A

    2015-09-01

    Mucins are among the many important constituents of a healthy tear film. Mucins secreted and/or associated with conjunctival goblet cells, ocular mucosal epithelial cells, and the lacrimal gland must work together to create a stable tear film. Although many studies have explored the mechanism(s) whereby mucins maintain and protect the ocular surface, the effects of dry eye on the structure and function of ocular mucins are unclear. Here, we summarize current findings regarding ocular mucins and how they are altered in dry eye. We performed a literature review of studies exploring the expression of mucins produced and/or associated with tissues that comprise the lacrimal functional unit and how they are altered in dry eye. We also summarize new insights on the immune-mediated effects of aqueous tear deficiency on ocular surface mucins that we discovered using a mouse model of dry eye. Although consistent decreases in MUC5AC and altered expression of membrane-bound mucins have been noted in both Sjögren and non-Sjögren dry eye, many reports of altered mucins in dry eye are contradictory. Mechanistic studies, including our own, suggest that changes in the glycosylation of mucins rather than the proteins themselves may occur as the direct result of local inflammation induced by proinflammatory mediators, such as interleukin-1. Altered expression of ocular mucins in dry eye varies considerably from study to study, likely attributed to inherent difficulties in analyzing small-volume tear samples, as well as differences in tear collection methods and disease severity in dry eye cohorts. To better define the functional role of ocular mucin glycosylation in the pathogenesis of dry eye disease, we propose genomic and proteomic studies along with biological pathway analysis to reveal novel avenues for exploration.

  6. Does the thickening of Achilles tendon and plantar fascia contribute to the alteration of diabetic foot loading?

    Science.gov (United States)

    Giacomozzi, C; D'Ambrogi, E; Uccioli, L; Macellari, V

    2005-06-01

    The diabetic foot often undergoes abnormal plantar pressures, changing in walking strategy, ulcerative processes. The present study focuses on the effects that diabetes-induced alterations of Achilles tendon, plantar fascia and first metatarso-phalangeal joint-both anatomical and functional-may have on foot loading. Sixty-one diabetic patients, with or without neuropathy, and 21 healthy volunteers were recruited. Thickness of Achilles tendon and plantar fascia was measured by ultrasound. Flexion-extension of the first metatarso-phalangeal joint was measured passively. Main biomechanic parameters of foot-floor interaction during gait were acquired and related to the above measurements. Plantar fascia and Achilles tendon were significantly (Pplantar fascia, respectively, and 4.0 mm (0.5), 4.6 mm (1.0) and 4.9 mm (1.7) for Achilles tendon, respectively. Flexion-extension of the first metatarso-phalangeal joint was significantly (Pplantar fascia and Achilles tendon in diabetics, more evident in the presence of neuropathy, concurs to develop a rigid foot, which poorly absorbs shock during landing (performs the physiological impact force absorption during landing). More generally, an overall alteration of the foot-ankle complex motion likely occurs throughout the whole gait cycle, which partly explains the abnormal loading under the forefoot.

  7. R7T7 glass alteration mechanism in an aqueous closed system: understanding and modelling the long term alteration kinetic

    International Nuclear Information System (INIS)

    Chave, T.

    2007-10-01

    The long term alteration rate of the French R7T7 nuclear glass has been investigated since many years because it will define the overall resistance of the radionuclide containment matrix. Recent studies have shown that the final rate remains constant or is slightly decreasing with time. It never reaches zero. Though this residual rate is very low, only 5 nm per year at 50 C, it would be the dominant alteration phenomenon in a geological repository. Two mechanisms are suggested for explaining such behaviour: diffusion in solution of elements from glass through an amorphous altered layer and precipitation of neo-formed phases. The diffusion processes are in agreement with a solid state diffusion mechanism and can lead to secondary phase precipitation due to solution concentration increases. Observed phases are mainly phyllosilicates and zeolites, in specific conditions. Phyllosilicates are expected to maintain the residual kinetic rate whereas alteration resumption could be observed in presence of zeolites at very high pH or temperature (10.5 at 90 C or temperature above 150 C). Both diffusion and neo-formed phase precipitation have been investigated in order to better understand their impact on the residual alteration rate and have then been modelled by a calculation code, coupling chemistry and transport, in order to be able to better anticipate the long term behaviour of the glass R7T7 in an aqueous closed system. (author)

  8. Geochemical behaviour of uranium in the cycle of alteration; Comportement geochimique de l'uranium dans le cycle d'alteration

    Energy Technology Data Exchange (ETDEWEB)

    Chervet, J; Coulomb, R [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Soudan, P [Centre d' Etude de Lalumine, Compagnie Pechiney (France)

    1958-07-01

    The investigation of the genesis of secondary mineralized accumulations, and the prospecting of deposits from microchemical anomalies in the surface material, is requiring a well-developed knowledge of the geochemical properties of the uranium during the alteration phase. In the present work, the authors tried to track the uranium history during a part of his natural creeping. a) They describe some most typical mineralogical observations of alteration phenomena and material migration, picked up in place on the deposits. b) They give experimental results concerning the solubilities of the uranium minerals and the factors affecting this solubility. c) They study the water circulation in granitic batholites, and the influence of the occurrence of the uranium deposits on their composition. d) They observe the amplitude of phenomena restricting the dispersions: fixations, precipitations, etc., and the behaviour of growth in uraniferous areas. e) Finally, the opposition chemical alteration-radioactive equilibrium results in an important imbalance in altered materials. The authors tried to use the measurement of this imbalance to explain geochemical processes. (author) [French] L'etude des conditions de genese des accumulations minerales secondaires, ainsi que la prospection des gisements a partir d'anomalies microchimiques dans les materiaux de surface, necessite une connaissance approfondie des proprietes geochimiques fondamentales de l'uranium dans la phase d'alteration. Nous essayons, dans ce travail, de suivre l'histoire de l'uranium dans une partie de son cheminement naturel. a) Nous decrivons quelques observations mineralogiques particulierement typiques de phenomenes d'alteration et de migration de matiere, prises 'in situ' dans les gisements. b) Nous donnons les resultats d'experiences de laboratoire sur les solubilites de mineraux d'uranium et sur les facteurs influen nt cette solubilite. c) Nous etudions les circulations d'eaux sur les massifs granitiques et

  9. High salt diet induces metabolic alterations in multiple biological processes of Dahl salt-sensitive rats.

    Science.gov (United States)

    Wang, Yanjun; Liu, Xiangyang; Zhang, Chen; Wang, Zhengjun

    2018-06-01

    High salt induced renal disease is a condition resulting from the interactions of genetic and dietary factors causing multiple complications. To understand the metabolic alterations associated with renal disease, we comprehensively analyzed the metabonomic changes induced by high salt intake in Dahl salt-sensitive (SS) rats using GC-MS technology and biochemical analyses. Physiological features, serum chemistry, and histopathological data were obtained as complementary information. Our results showed that high salt (HS) intake for 16 weeks caused significant metabolic alterations in both the renal medulla and cortex involving a variety pathways involved in the metabolism of organic acids, amino acids, fatty acids, and purines. In addition, HS enhanced glycolysis (hexokinase, phosphofructokinase and pyruvate kinase) and amino acid metabolism and suppressed the TCA (citrate synthase and aconitase) cycle. Finally, HS intake caused up-regulation of the pentose phosphate pathway (glucose 6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase), the ratio of NADPH/NADP + , NADPH oxidase activity and ROS production, suggesting that increased oxidative stress was associated with an altered PPP pathway. The metabolic pathways identified may serve as potential targets for the treatment of renal damage. Our findings provide comprehensive biochemical details about the metabolic responses to a high salt diet, which may contribute to the understanding of renal disease and salt-induced hypertension in SS rats. Copyright © 2018. Published by Elsevier Inc.

  10. A multiscale approach to modelling electrochemical processes occurring across the cell membrane with application to transmission of action potentials.

    Science.gov (United States)

    Richardson, G

    2009-09-01

    By application of matched asymptotic expansions, a simplified partial differential equation (PDE) model for the dynamic electrochemical processes occurring in the vicinity of a membrane, as ions selectively permeate across it, is formally derived from the Poisson-Nernst-Planck equations of electrochemistry. It is demonstrated that this simplified model reduces itself, in the limit of a long thin axon, to the cable equation used by Hodgkin and Huxley to describe the propagation of action potentials in the unmyelinated squid giant axon. The asymptotic reduction from the simplified PDE model to the cable equation leads to insights that are not otherwise apparent; these include an explanation of why the squid giant axon attains a diameter in the region of 1 mm. The simplified PDE model has more general application than the Hodgkin-Huxley cable equation and can, e.g. be used to describe action potential propagation in myelinated axons and neuronal cell bodies.

  11. Assessment of diagenetic alteration of dinosaur eggshells through petrography and geochemical analysis

    Science.gov (United States)

    Enriquez, M. V.; Eagle, R.; Eiler, J. M.; Tripati, A. K.; Ramirez, P. C.; Loyd, S. J.; Chiappe, L.; Montanari, S.; Norell, M.; Tuetken, T.

    2012-12-01

    Carbonate clumped isotope analysis of fossil eggshells has the potential to constrain both the physiology of extinct animals and, potentially, paleoenvironmental conditions, especially when coupled with isotopic measurements of co-occurring soil carbonates. Eggshell samples from both modern vertebrates and Cretaceous Hadrosaurid, Oviraptorid, Titanosaur, Hypselosaurus, Faveoolithus, dinosaur fossils have been collected from Auca Mahuevo, Argentina and Rousett, France, amongst other locations, for geochemical analysis to determine if isotopic signatures could be used to indicate warm- or cold-bloodedness. In some locations soil carbonates were also analyzed to constrain environmental temperatures. In order to test the validity of the geochemical results, an extensive study was undertaken to establish degree of diagenetic alteration. Petrographic and cathodoluminescence characterization of the eggshells were used to assess diagenetic alteration. An empirical 1-5 point scale was used to assign each sample an alteration level, and the observations were then compared with the geochemical results. Specimens displayed a wide range of alteration states. Some of which were well preserved and others highly altered. Another group seemed to be structural intact and only under cathodoluminescence was alteration clearly observed. In the majority of samples, alteration level was found to be predictably related to geochemical results. From specimens with little evidence for diagenesis, carbonate clumped isotope signatures support high (37-40°C) body temperature for Titanosaurid dinosaurs, but potentially lower body temperatures for other taxa. If these data do, in fact, represent original eggshell growth temperatures, these results support variability in body temperature amongst Cretaceous dinosaurs and potentially are consistent with variations between adult body temperature and size — a characteristic of 'gigantothermy'.

  12. New Altered Non-Fibrillar Collagens in Human Dilated Cardiomyopathy: Role in the Remodeling Process.

    Directory of Open Access Journals (Sweden)

    Carolina Gil-Cayuela

    Full Text Available In dilated cardiomyopathy (DCM, cardiac failure is accompanied by profound alterations of extracellular matrix associated with the progression of cardiac dilation and left ventricular (LV dysfunction. Recently, we reported alterations of non-fibrillar collagen expression in ischemic cardiomyopathy linked to fibrosis and cardiac remodeling. We suspect that expression changes in genes coding for non-fibrillar collagens may have a potential role in DCM development.This study sought to analyze changes in the expression profile of non-fibrillar collagen genes in patients with DCM and to examine relationships between cardiac remodeling parameters and the expression levels of these genes.Twenty-three human left ventricle tissue samples were obtained from DCM patients (n = 13 undergoing heart transplantation and control donors (n = 10 for RNA sequencing analysis. We found increased mRNA levels of six non-fibrillar collagen genes, such as COL4A5, COL9A1, COL21A1, and COL23A1 (P < 0.05 for all, not previously described in DCM. Protein levels of COL8A1 and COL16A1 (P < 0.05 for both, were correspondingly increased. We also identified TGF-β1 significantly upregulated and related to both COL8A1 and COL16A1. Interestingly, we found a significant relationship between LV mass index and the gene expression level of COL8A1 (r = 0.653, P < 0.05.In our research, we identified new non-fibrillar collagens with altered expression in DCM, being COL8A1 overexpression directly related to LV mass index, suggesting that they may be involved in the progression of cardiac dilation and remodeling.

  13. When "altering brain function" becomes "mind control".

    Science.gov (United States)

    Koivuniemi, Andrew; Otto, Kevin

    2014-01-01

    Functional neurosurgery has seen a resurgence of interest in surgical treatments for psychiatric illness. Deep brain stimulation (DBS) technology is the preferred tool in the current wave of clinical experiments because it allows clinicians to directly alter the functions of targeted brain regions, in a reversible manner, with the intent of correcting diseases of the mind, such as depression, addiction, anorexia nervosa, dementia, and obsessive compulsive disorder. These promising treatments raise a critical philosophical and humanitarian question. "Under what conditions does 'altering brain function' qualify as 'mind control'?" In order to answer this question one needs a definition of mind control. To this end, we reviewed the relevant philosophical, ethical, and neurosurgical literature in order to create a set of criteria for what constitutes mind control in the context of DBS. We also outline clinical implications of these criteria. Finally, we demonstrate the relevance of the proposed criteria by focusing especially on serendipitous treatments involving DBS, i.e., cases in which an unintended therapeutic benefit occurred. These cases highlight the importance of gaining the consent of the subject for the new therapy in order to avoid committing an act of mind control.

  14. Basic perceptual changes that alter meaning and neural correlates of recognition memory.

    Science.gov (United States)

    Gao, Chuanji; Hermiller, Molly S; Voss, Joel L; Guo, Chunyan

    2015-01-01

    It is difficult to pinpoint the border between perceptual and conceptual processing, despite their treatment as distinct entities in many studies of recognition memory. For instance, alteration of simple perceptual characteristics of a stimulus can radically change meaning, such as the color of bread changing from white to green. We sought to better understand the role of perceptual and conceptual processing in memory by identifying the effects of changing a basic perceptual feature (color) on behavioral and neural correlates of memory in circumstances when this change would be expected to either change the meaning of a stimulus or to have no effect on meaning (i.e., to influence conceptual processing or not). Abstract visual shapes ("squiggles") were colorized during study and presented during test in either the same color or a different color. Those squiggles that subjects found to resemble meaningful objects supported behavioral measures of conceptual priming, whereas meaningless squiggles did not. Further, changing color from study to test had a selective effect on behavioral correlates of priming for meaningful squiggles, indicating that color change altered conceptual processing. During a recognition memory test, color change altered event-related brain potential (ERP) correlates of memory for meaningful squiggles but not for meaningless squiggles. Specifically, color change reduced the amplitude of frontally distributed N400 potentials (FN400), implying that these potentials indicated conceptual processing during recognition memory that was sensitive to color change. In contrast, color change had no effect on FN400 correlates of recognition for meaningless squiggles, which were overall smaller in amplitude than for meaningful squiggles (further indicating that these potentials signal conceptual processing during recognition). Thus, merely changing the color of abstract visual shapes can alter their meaning, changing behavioral and neural correlates of memory

  15. Geochemical behaviour of uranium in the cycle of alteration

    International Nuclear Information System (INIS)

    Chervet, J.; Coulomb, R.

    1958-01-01

    The investigation of the genesis of secondary mineralized accumulations, and the prospecting of deposits from microchemical anomalies in the surface material, is requiring a well-developed knowledge of the geochemical properties of the uranium during the alteration phase. In the present work, the authors tried to track the uranium history during a part of his natural creeping. a) They describe some most typical mineralogical observations of alteration phenomena and material migration, picked up in place on the deposits. b) They give experimental results concerning the solubilities of the uranium minerals and the factors affecting this solubility. c) They study the water circulation in granitic batholites, and the influence of the occurrence of the uranium deposits on their composition. d) They observe the amplitude of phenomena restricting the dispersions: fixations, precipitations, etc., and the behaviour of growth in uraniferous areas. e) Finally, the opposition chemical alteration-radioactive equilibrium results in an important imbalance in altered materials. The authors tried to use the measurement of this imbalance to explain geochemical processes. (author) [fr

  16. Characterization of {sup 238}U, {sup 232}Th, {sup 40}K, and {sup 226}Ra in NORM and Air Particulate Occurring from Phosphate Processing Facility

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Yoon Hee; Lim, Jong Myoung; Ji, Young Yong; Kim, Hyun Cheol; Kim, Chang Jong; Park, Ji Yong; Chung, Kun Ho; Kang, Mun Ja [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    In this study, radio-activities of {sup 238}U, {sup 232}Th, {sup 40}K, and {sup 226}Ra occurring in raw materials and by-products at phosphate processing facility were complementally determined using ED-XRF, γ-spectrometry and ICP-MS method. Although the degree of immersion in the human body varies depending on the particle size and density, the particle size is especially used as a key factor in assessing dose. Thus, size distribution characteristics of {sup 238}U concentrations in airborne particulates collected at the phosphate processing facility were also evaluated. The naturally occurring radioactive materials (NORM) are widely spread throughout the environment, it occupies the largest part of public radioactivity exposure. According to report of the US National Academy of Sciences, 82% of the human radiation dose received annually comes from the natural radionuclides. Radiation exposure doses from natural radionuclides is not significantly concerned level compared to those from artificial radionuclides which could be released into the environment by nuclear tests and power plant accident. It could make a serious risk problem to unspecific public when exposed to the natural radionuclides during long-term period at high activity concentration levels. Therefore, it is essential to make a professional and systematic approach for the proper handling and diminution.

  17. Improvements of sensorimotor processes during action cascading associated with changes in sensory processing architecture-insights from sensory deprivation.

    Science.gov (United States)

    Gohil, Krutika; Hahne, Anja; Beste, Christian

    2016-06-20

    In most everyday situations sensorimotor processes are quite complex because situations often require to carry out several actions in a specific temporal order; i.e. one has to cascade different actions. While it is known that changes to stimuli affect action cascading mechanisms, it is unknown whether action cascading changes when sensory stimuli are not manipulated, but the neural architecture to process these stimuli is altered. In the current study we test this hypothesis using prelingually deaf subjects as a model to answer this question. We use a system neurophysiological approach using event-related potentials (ERPs) and source localization techniques. We show that prelingually deaf subjects show improvements in action cascading. However, this improvement is most likely not due to changes at the perceptual (P1-ERP) and attentional processing level (N1-ERP), but due to changes at the response selection level (P3-ERP). It seems that the temporo-parietal junction (TPJ) is important for these effects to occur, because the TPJ comprises overlapping networks important for the processing of sensory information and the selection of responses. Sensory deprivation thus affects cognitive processes downstream of sensory processing and only these seem to be important for behavioral improvements in situations requiring complex sensorimotor processes and action cascading.

  18. Alterations in adaptive immunity persist during long-duration spaceflight

    Science.gov (United States)

    Crucian, Brian; Stowe, Raymond P; Mehta, Satish; Quiriarte, Heather; Pierson, Duane; Sams, Clarence

    2015-01-01

    Background: It is currently unknown whether immune system alterations persist during long-duration spaceflight. In this study various adaptive immune parameters were assessed in astronauts at three intervals during 6-month spaceflight on board the International Space Station (ISS). AIMS: To assess phenotypic and functional immune system alterations in astronauts participating in 6-month orbital spaceflight. Methods: Blood was collected before, during, and after flight from 23 astronauts participating in 6-month ISS expeditions. In-flight samples were returned to Earth within 48 h of collection for immediate analysis. Assays included peripheral leukocyte distribution, T-cell function, virus-specific immunity, and mitogen-stimulated cytokine production profiles. Results: Redistribution of leukocyte subsets occurred during flight, including an elevated white blood cell (WBC) count and alterations in CD8+ T-cell maturation. A reduction in general T-cell function (both CD4+ and CD8+) persisted for the duration of the 6-month spaceflights, with differential responses between mitogens suggesting an activation threshold shift. The percentage of CD4+ T cells capable of producing IL-2 was depressed after landing. Significant reductions in mitogen-stimulated production of IFNγ, IL-10, IL-5, TNFα, and IL-6 persisted during spaceflight. Following lipopolysaccharide (LPS) stimulation, production of IL-10 was reduced, whereas IL-8 production was increased during flight. Conclusions: The data indicated that immune alterations persist during long-duration spaceflight. This phenomenon, in the absence of appropriate countermeasures, has the potential to increase specific clinical risks for crewmembers during exploration-class deep space missions. PMID:28725716

  19. Modelling glass alteration in an altered argillaceous environment

    International Nuclear Information System (INIS)

    Bildstein, O.; Trotignon, L.; Pozo, C.; Jullien, M.

    2007-01-01

    The long term behaviour of materials such as glass, steel and clay has been investigated in the context of deep geological disposal of radioactive wastes. The interactions between vitrified wastes, canister corrosion products (CPs) and clay are studied using a modified version of the reaction-transport code Crunch, especially looking at pH changes and possible cementation at the interface with the clayey materials. These perturbations may indeed affect the lifetime of glass matrix in deep repositories, e.g., high pH enhances the rate of glass alteration. This work focuses on the argillite of Bure. The calculations were performed at 323 K with a glass alteration rate switching from a high initial rate to a residual rate according to the sorption capacity of CPs. The time at which this sorption capacity is saturated is crucial to the system in terms of wastes package lifetime. The results show that the glass alteration imposes a high pH value at the interface with CPs and clay: up to a value of 9.2, compared to 7.3 which is the initial pH value in the argillite. Experimental data show that the rate of glass alteration is much higher in such pH conditions. For a R7T7-type glass, the rate is about five times higher at pH 9 than at pH 7. This pH perturbation migrates through the clayey domain as a result of the migration of mobile elements such as boron and sodium, and despite the existence of strong pH buffers in the argillite. The cementation of porosity at the interface between glass and clay is predicted by the model due to the massive precipitation of iron corrosion products and glass alteration products. At this point of the evolution of the system, the pH starts to decrease and the alteration rate of the glass could be significantly reduced. This porosity clogging effect is difficult to confirm by experiments especially since existing data on short term experiments tend to show a pervasive precipitation of silica in the domain instead of a localized precipitation

  20. The epidermis of grhl3-null mice displays altered lipid processing and cellular hyperproliferation.

    Science.gov (United States)

    Ting, Stephen B; Caddy, Jacinta; Wilanowski, Tomasz; Auden, Alana; Cunningham, John M; Elias, Peter M; Holleran, Walter M; Jane, Stephen M

    2005-04-01

    The presence of an impermeable surface barrier is an essential homeostatic mechanism in almost all living organisms. We have recently described a novel gene that is critical for the developmental instruction and repair of the integument in mammals. This gene, Grainy head-like 3 (Grhl3) is a member of a large family of transcription factors that are homologs of the Drosophila developmental gene grainy head (grh). Mice lacking Grhl3 fail to form an adequate skin barrier, and die at birth due to dehydration. These animals are also unable to repair the epidermis, exhibiting failed wound healing in both fetal and adult stages of development. These defects are due, in part, to diminished expression of a Grhl3 target gene, Transglutaminase 1 (TGase 1), which encodes a key enzyme involved in cross-linking of epidermal structural proteins and lipids into the cornified envelope (CE). Remarkably, the Drosophila grh gene plays an analogous role, regulating enzymes involved in the generation of quinones, which are essential for cross-linking structural components of the fly epidermis. In an extension of our initial analyses, we focus this report on additional defects observed in the Grhl3-null epidermis, namely defective extra-cellular lipid processing, altered lamellar lipid architecture and cellular hyperproliferation. These abnormalities suggest that Grhl3 plays diverse mechanistic roles in maintaining homeostasis in the skin.

  1. The ecological limits of hydrologic alteration (ELOHA): A new framework for developing regional environmental flow standards

    Science.gov (United States)

    Poff, N.L.; Richter, B.D.; Arthington, A.H.; Bunn, S.E.; Naiman, R.J.; Kendy, E.; Acreman, M.; Apse, C.; Bledsoe, B.P.; Freeman, Mary C.; Henriksen, J.; Jacobson, R.B.; Kennen, J.G.; Merritt, D.M.; O'Keeffe, J. H.; Olden, J.D.; Rogers, K.; Tharme, R.E.; Warner, A.

    2010-01-01

    region are classified into a few distinctive flow regime types that are expected to have different ecological characteristics. These river types can be further subclassified according to important geomorphic features that define hydraulic habitat features. Third, the deviation of current-condition flows from baseline-condition flow is determined. Fourth, flow alteration-ecological response relationships are developed for each river type, based on a combination of existing hydroecological literature, expert knowledge and field studies across gradients of hydrologic alteration. 4. Scientific uncertainty will exist in the flow alteration-ecological response relationships, in part because of the confounding of hydrologic alteration with other important environmental determinants of river ecosystem condition (e.g. temperature). Application of the ELOHA framework should therefore occur in a consensus context where stakeholders and decision-makers explicitly evaluate acceptable risk as a balance between the perceived value of the ecological goals, the economic costs involved and the scientific uncertainties in functional relationships between ecological responses and flow alteration. 5. The ELOHA framework also should proceed in an adaptive management context, where collection of monitoring data or targeted field sampling data allows for testing of the proposed flow alteration-ecological response relationships. This empirical validation process allows for a fine-tuning of environmental flow management targets. The ELOHA framework can be used both to guide basic research in hydroecology and to further implementation of more comprehensive environmental flow management of freshwater sustainability on a global scale. ?? 2009 Blackwell Publishing Ltd.

  2. Cumulative and competitive effects of chemical elements on nuclear glass alteration

    International Nuclear Information System (INIS)

    Arena, Helene

    2016-01-01

    This work takes place in the context of the long-term behavior of nuclear glasses under repository conditions. The main objective is to identify, understand and compare the effects of some chemical elements present in the glass composition and/or in the repository media (Zn, Mg, Ni, Co, Fe, Ca, Gd, Ce, K, Cs, Cr and Ag) on the processes involved in glass alteration by water. The cumulative or competitive nature of the effects of these chemical elements was determined. To reach this goal, a 6 oxides simple glass (ISG) has been altered for more than 500 days in a solution containing one or more of the chemical elements of interest. The results indicate that Zn, Mg, Ni, Co and Fe elements increase glass alteration forming secondary phases with the same structure and stoichiometry (tri-octahedral smectites). To form, these silicates consume chemical elements (Si, Al) from the environment and induce a pH decrease until a limiting value of pH. Beyond this pH the precipitation of secondary phases is inhibited and these chemical elements can be integrated into the gel, replacing Ca whose solubility increases at lower pH. As long as they form secondary phases, the effects of these elements are cumulative. Rare earths Gd and Ce also increase glass alteration forming secondary phases but their effects are lower as they contain less silicon. These elements are not integrated in the gel. Chromium increases glass alteration by precipitating with Ca and leading to a less protective gel, depleted in Ca. Silver precipitates as AgCl and has no effect on the alteration of the glass. The chemical elements K, Cs and Ca limit glass alteration by integrating into the gel and slowing down the transport phenomena therein. This integration is competitive: the order of integration (quantity and effectiveness glass alteration limitation) is the following Ca≥≥Cs≥K. Thus, the increase of glass alteration may be proportional to the quantity of elements promoting the precipitation of

  3. Altered frontocingulate activation during aversive interoceptive processing in young adults transitioning to problem stimulant use

    Directory of Open Access Journals (Sweden)

    Jennifer Lorraine Stewart

    2013-11-01

    Full Text Available Problems associated with stimulant use have been linked to frontocingulate, insular, and thalamic dysfunction during decision-making and alterations in interoceptive processing. However, little is known about how interoception and decision-making interact and contribute to dysfunctions that promote the transition from recreational drug use to abuse or dependence. Here, we investigate brain activation in response to reward, punishment, and uncertainty during an aversive interoceptive challenge in current and former stimulant (cocaine and amphetamine users using functional magnetic resonance imaging (fMRI. Young adults previously identified as recreational users (n=184 were followed up three years later. Of these, 18 individuals progressed to problem stimulant use (PSU, whereas 15 desisted stimulant use (DSU. PSU, DSU, and 14 healthy comparison subjects (CTL performed a two-choice prediction task at three fixed error rates (20%=reward, 50%=uncertainty, 80%=punishment during which they anticipated and experienced episodes of inspiratory breathing load. Although groups did not differ in insula activation or subjective breathing load ratings, PSU exhibited lower right inferior frontal gyrus (IFG and bilateral anterior cingulate (ACC activation than DSU and CTL during aversive interoceptive processing as well as lower right IFG in response to decision making involving uncertainty. However, PSU exhibited greater bilateral IFG activation than DSU and CTL while making choices within the context of punishing feedback, and both PSU and DSU showed lower thalamic activation during breathing load than CTL. Findings suggest that frontocingulate attenuation, reflecting reduced resources devoted to goal maintenance and action selection in the presence of uncertainty and interoceptive perturbations, may be a biomarker for susceptibility to problem stimulant use.

  4. Shear zone-related pseudotachylite occurences from the northern Transvaal

    International Nuclear Information System (INIS)

    Reimold, W.U.; Meyer, F.M.

    1990-01-01

    Pseudotachylite from the Sand River localities displays very variable composition when formed in Sand River Gneiss, but is less variable when originating from diabase. Comparison of individual pseudotachylite (granitic) host rock pairs shows consistent depletion and enrichment. Rather high LoI values indicate significant secondary alteration for some specimens. The chemical variations agree well with the theory that pseudotachylite in granitic-granodioritic environment is formed by preferential melting of hydrous ferromagnesian minerals plus varied proportions of feldspar components. 'Basaltic' pseudotachylite is characterised by increase of SiO 2 and K 2 O, which is also known from other occurences. With respect to most trace elements, pseudotachylite is generally enriched. Comparison of all pseudotachylite analyses with Sand River Gneiss data reveals that mixing on a dm scale cannot be completely excluded, but 'basaltic' pseudotachilyte obtained in granodioritic host rock has not assimilated more than approximately 5% of felsic material. The cataclastic breccias chemically compare well with undeformed Sand River Gneiss. These results agree well with current theory on pseudotachylite formation, but at the Geocongress a larger data base will be discussed. 1 fig., 6 refs

  5. Geothermometry, geochronology, and mass transfer associated with hydrothermal alteration of a rhyolitic hyaloclastite from Ponza Island, Italy

    Science.gov (United States)

    Altaner, S.P.; Ylagan, R.F.; Savin, S.M.; Aronson, J.L.; Belkin, H.E.; Pozzuoli, A.

    2003-01-01

    A rhyolitic hyaloclastite from Ponza Island, Italy, was hydrothermally altered, producing four distinct alteration zones based on X-ray diffraction mineralogy and field textures: (1) nonpervasive argillic zone; (2) propylitic zone; (3) silicic zone; and (4) sericitic zone. The unaltered hyaloclastite is volcanic breccia with clasts of vesiculated obsidian in a matrix of predominantly pumice lapilli. Incomplete alteration of the hyaloclastite resulted in the nonpervasive argillic zone, characterized by smectite and disordered opal-CT. The other three zones exhibit more complete alteration of the hyaloclastite. The propylitic zone is characterized by mixed-layer illite-smectite (I-S) with 10 to 85% I, mordenite, opal-C, and authigenic K-feldspar (akspar). The silicic zone is characterized by I-S with ???90% I, pure illite, quartz, akspar, and occasional albite. The sericitic zone consists primarily of I-S with ???66% I, pure illite, quartz, and minor akspar and pyrite. K/Ar dates of I-S indicate hydrothermal alteration occurred at 3.38 ?? 0.08 Ma. Oxygen isotope compositions of I-S systematically decrease from zones 1 to 4. In the argillic zone, smectite has ??18 O values of 21.7 to 22.0??? and I-S from the propylitic, silicic, and sericitic zones ranges from 14.5 to 16.3???, 12.5 to 14.0???, and 8.6 to 11.9???, respectively. ??18 O values for quartz from the silicic and sericitic zones range from 12.6 to 15.9???. By use of isotope fractionation equations and data from authigenic quartz-hosted primary fluid inclusions, alteration temperatures ranged from 50 to 65 ??C for the argillic zone, 85 to 125 ??C for the propylitic zone, 110 to 210 ??C for the silicic zone, and 145 to 225 ??C for the sericitic zone. Fluid inclusion data and calculated ??18 O water values indicate that hydrothermal fluids were seawater dominated. Mass-transfer calculations indicate that hydrothermal alteration proceeded in a relatively open chemical system and alteration in the sericitic zone

  6. Transformation of the genital epithelial tract occurs early in California sea lion development

    Science.gov (United States)

    Barragán-Vargas, Cecilia; Montano-Frías, Jorge; Ávila Rosales, Germán; Godínez-Reyes, Carlos R.; Acevedo-Whitehouse, Karina

    2016-01-01

    An unusually high prevalence of metastatic urogenital carcinoma has been observed in free-ranging California sea lions stranded off the coast of California in the past two decades. No cases have been reported for sea lions in the relatively unpolluted Gulf of California. We investigated occurrence of genital epithelial transformation in 60 sea lions (n=57 pups and 3 adult females) from the Gulf of California and examined whether infection by a viral pathogen previously found to be associated with urogenital carcinoma accounted for such alterations. We also explored the contribution of MHC class II gene expression on transformation. Cellular alterations, such as squamous cell atypia (ASC), atypical squamous cells of undetermined significance (ASCUS) and low-grade squamous intraepithelial lesions were observed in 42% of the pups and in 67% of the adult females. Normal genital epithelium was more common in male than female pups. ASC was five times more likely to occur in older pups. Epithelial alterations were unrelated to infection by the potentially oncogenic otarine type I gammaherpesvirus (OtHV-1), but ASCUS was more common in pups with marked and severe inflammation. Expression of MHC class II DRB loci (Zaca DRB-D) by peripheral antigen-presenting leucocytes showed a slightly ‘protective’ effect for ASC. We propose that transformation of the California sea lion genital epithelium is relatively common in young animals, increases with age and is probably the result of infection by an unidentified pathogen. Expression of a specific MHC class II gene, suggestive of presentation of specific antigenic peptides to immune effectors, appears to lower the risk of transformation. Our study provides the first evidence that epithelial transformation of the California sea lion genital tract is relatively common, even from an early age, and raises questions regarding differences in sea lion cancer-detection and -repair success between geographical regions. PMID:27069641

  7. On the noble gas isotopic fractionation in naturally occurring gases

    International Nuclear Information System (INIS)

    Marty, B.

    1984-01-01

    The isotopic composition of neon in the mantle is an important geochemical constraint on the formation of the earth and subsequent degassing. Some deviation of neon isotopic composition in natural gas and rock samples from the atmospheric value which can not be accounted for by the known nuclear process has been reported, and Nagao et al. interpreted the deviation as the result of mass fractionation in natural gas in Japan. The possible cause of such fractionation was investigated. Gaseous diffusion, such as (a) free-molecule diffusion, (b) mutual diffusion and (c) thermal diffusion, is able to cause isotopic fractionation. After the detailed consideration on these three diffusion processes, conclusion that free-molecule diffusion occurs only in very particular condition, and it is questionable that thermal diffusion occurs in nature, were obtained. (b) which means the interaction of two or more gases, is supposed to occur in nature, and is able to confirm experimentally. In mutual diffusion only, gas transfer is concerned, but other form of fractionation should not be neglected. In solid diffusion, gas is trapped by fine grained sedimentary rocks, and may be fractionated by adsorption and communication to exterior through minute channels. Underground water also works as noble gas reservoir. For example, when gas stream is in contact with water, continuous exchange is possible to take place at the interface of gas and liquid, which contributes to the fractionation. (Ishimitsu, A.)

  8. Genesis of hydrothermal alterations using stable isotope geochemistry in Takestan area (Tarom zone

    Directory of Open Access Journals (Sweden)

    Batool Taghipou

    2015-12-01

    Full Text Available Hydrothermal alteration processes are extensively took place on volcanic and pyroclstics of Takestan area. Existence of abundant, deep fracturing and subvolcanic intrusions are enhanced extend hydrothermal alteration zones. The following alteration zones are determined: propylitic, argillic, advanced argillic and sillicic. There are outcropped and widespread in different size and limit. Formation of siliceous sinter, silicified tuffs with preserved primary sedimentary layering including pure mineralized alunite patches are most outstanding. Quartz, sussoritic plagioclase, chlorite, sericite and alunite are main mineral constituents in the volcanics. On the basis of geochemical data volcanic rocks are rhyolite, dacite, andesite, andesitic-basalt and basalt in composition. Acid-sulfate zone is the type of alteration in Tarom area and alunite is an index mineral of this zone. Results of 18O, D and 34S stable isotope geochemistry on altered minerals (muscovite, kaolinite and alunite, revealed that alteration fluids are magmatic in origin.

  9. A study on mineralization U,REE and related processes in anomaly No.6 Khoshomy area central Iran

    International Nuclear Information System (INIS)

    Heidaryan, F.

    2005-01-01

    Uranium mineralization in Khoshomy prospect, located in central. part of Iran, with 303-15000 (cps) and 14 to 4000 (ppm) released, The main rock types include: gneiss, granite, pegmatite and migmatite, that influenced by pegmatite-albitic vines (quartz-heldespatic). Acidic and basic dykes, granodioritic, units and dolomite and marble have been seen. The alteration associated with the mineralization is potassic, argillic, propylitic, carbonization, silisificaition and hematitizaition. Uranium mineralization occurred in a hydrothermal phase with Cu, Mo, Ni and Au elements. Uranium primary minerals include pitchblende, coffinite, uraninite; and uranium secondary minerals include uranophane and . boltwoodite. REE mineralization occurred by the potassic phase in peginatitization process

  10. Interplay between glutamatergic and GABAergic neurotransmission alterations in cognitive and motor impairment in minimal hepatic encephalopathy.

    Science.gov (United States)

    Llansola, Marta; Montoliu, Carmina; Agusti, Ana; Hernandez-Rabaza, Vicente; Cabrera-Pastor, Andrea; Gomez-Gimenez, Belen; Malaguarnera, Michele; Dadsetan, Sherry; Belghiti, Majedeline; Garcia-Garcia, Raquel; Balzano, Tiziano; Taoro, Lucas; Felipo, Vicente

    2015-09-01

    The cognitive and motor alterations in hepatic encephalopathy (HE) are the final result of altered neurotransmission and communication between neurons in neuronal networks and circuits. Different neurotransmitter systems cooperate to modulate cognitive and motor function, with a main role for glutamatergic and GABAergic neurotransmission in different brain areas and neuronal circuits. There is an interplay between glutamatergic and GABAergic neurotransmission alterations in cognitive and motor impairment in HE. This interplay may occur: (a) in different brain areas involved in specific neuronal circuits; (b) in the same brain area through cross-modulation of glutamatergic and GABAergic neurotransmission. We will summarize some examples of the (1) interplay between glutamatergic and GABAergic neurotransmission alterations in different areas in the basal ganglia-thalamus-cortex circuit in the motor alterations in minimal hepatic encephalopathy (MHE); (2) interplay between glutamatergic and GABAergic neurotransmission alterations in cerebellum in the impairment of cognitive function in MHE through altered function of the glutamate-nitric oxide-cGMP pathway. We will also comment the therapeutic implications of the above studies and the utility of modulators of glutamate and GABA receptors to restore cognitive and motor function in rats with hyperammonemia and hepatic encephalopathy. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Elemental and isotopic (Si-{sup 29} and O-{sup 18}) tracing of glass alteration mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Verney-Carron, A.; Libourel, G.; Deloule, E. [CNRS, Ctr Rech Petrog and Geochim, UPR 2300, F-54501 Vandoeuvre Les Nancy (France); Valle, N. [Ctr Rech Publ Gabriel Lippmann, Dept Sci and Anal Mat, L-4422 Belvaux (Luxembourg); Sterpenich, J. [Univ H Poincare, G2R, CNRS, UMR 7566, F-54501 Vandoeuvre Les Nancy (France); Jollivet, P. [CEA Marcoule, DEN, Lab Comportement Long Terme, F-30207 Bagnols Sur Ceze (France)

    2010-07-01

    To better understand glass alteration mechanisms, especially alteration layers formation, leaching experiments of a borosilicate glass (SON68) doped with a different rare earth element (La, Ce, or Nd) with solutions rich in {sup 29}Si and {sup 18}O were carried out. The coupled analyses of glass, alteration products, and solution led to a complete elemental and isotopic ({sup 29}Si and {sup 18}O) budget. They revealed different behaviours of elements that depend not only on their structural role in the glass, but also on their affinity for alteration products (gel, phyllosilicates, phosphates). However, analyses of both glass and solution are not sufficient to describe the real exchanges occurring between glass and solution. The use of {sup 29}Si and {sup 18}O tracers gives new insights on the formation of alteration layers. During alteration the phyllosilicates records the isotopic variations of the leaching solution. Their isotopic signatures highlight a mechanism of dissolution/precipitation, which implies equilibrium between the secondary phases and the solution. On the other hand the gel isotopic signature, that is intermediate between the glass and the solution, substantiates the hypothesis that the gel is formed by hydrolysis/condensation reactions. This mechanism can thus explain the influence of the gel formation conditions (alteration conditions, solution saturation) on the structure (reorganisation) and texture (porosity) of this layer and on its protective effect. These hydrolysis/condensation reactions are also certainly involved in the aluminosilicate glass alteration and in the formation of palagonite. (authors)

  12. How to measure a-few-nanometer-small LER occurring in EUV lithography processed feature

    Science.gov (United States)

    Kawada, Hiroki; Kawasaki, Takahiro; Kakuta, Junichi; Ikota, Masami; Kondo, Tsuyoshi

    2018-03-01

    For EUV lithography features we want to decrease the dose and/or energy of CD-SEM's probe beam because LER decreases with severe resist-material's shrink. Under such conditions, however, measured LER increases from true LER, due to LER bias that is fake LER caused by random noise in SEM image. A gap error occurs between the right and the left LERs. In this work we propose new procedures to obtain true LER by excluding the LER bias from the measured LER. To verify it we propose a LER's reference-metrology using TEM.

  13. Alteration mineral mapping for iron prospecting using ETM+ data, Tonkolili iron field, northern Sierra Leone

    Science.gov (United States)

    Mansaray, Lamin R.; Liu, Lei; Zhou, Jun; Ma, Zhimin

    2013-10-01

    The Tonkolili iron field in northern Sierra Leone has the largest known iron ore deposit in Africa. It occurs in a greenstone belt in an Achaean granitic basement. This study focused mainly on mapping areas with iron-oxide and hydroxyl bearing minerals, and identifying potential areas for haematite mineralization and banded iron formations (BIFs) in Tonkolili. The predominant mineral assemblage at the surface (laterite duricrust) of this iron field is haematitegoethite- limonite ±magnetite. The mineralization occurs in quartzitic banded ironstones, layered amphibolites, granites, schists and hornblendites. In this study, Crosta techniques were applied on Enhanced Thematic Mapper (ETM+) data to enhance areas with alteration minerals and target potential areas of haematite and BIF units in the Tonkolili iron field. Synthetic analysis shows that alteration zones mapped herein are consistent with the already discovered magnetite BIFs in Tonkolili. Based on the overlaps of the simplified geological map and the remote sensing-based alteration mineral maps obtained in this study, three new haematite prospects were inferred within, and one new haematite prospect was inferred outside the tenement boundary of the Tonkolili exploration license. As the primary iron mineral in Tonkolili is magnetite, the study concludes that, these haematite prospects could also be underlain by magnetite BIFs. This study also concludes that, the application of Crosta techniques on ETM+ data is effective not only in mapping iron-oxide and hydroxyl alterations but can also provide a basis for inferring areas of potential iron resources in Algoma-type banded iron formations (BIFs), such as those in the Tonkolili field.

  14. Geology and porphyry copper-type alteration-mineralization of igneous rocks at the Christmas Mine, Gila County, Arizona

    Science.gov (United States)

    Koski, Randolph A.

    1979-01-01

    igneous rocks is progressively more alkaline and silicic from basalt to granodiorite. Early (Stage I) chalcopyrite-bornite (-molybdenite) mineralization and genetically related K-silicate alteration are centered on the Christmas stock. K-silicate alteration is manifested by pervasive hornblende-destructive biotitization in the stock, biotitization of basaltic volcanic wall rocks, and a continuous stockwork of K-feldspar veinlets and quartz-K-feldspar veins in the stock and quartz-sulfide veins in volcanic rocks. Younger (Stage II) pyrite-chalcopyrite mineralization and quartz-sericite-chlorite alteration occur in a zone overlapping with but largely peripheral to the zone of Stage I stockwork veins. Within the Christmas intrusive complex, K-silicate-altered rocks in the central stock are flanked east and west by zones of fracture-controlled quartz-sericite alteration and strong pyritization. In volcanic rocks quartz-chlorite-pyrite-chalcopyrite veins are superimposed on earlier biotitization and crosscut Stage I quartz-sulfide veins. Beyond the zones of quartz-sericite alteration, biotite rhyodacite porphyry dikes contain the propylitic alteration assemblage epidote-chlorite-albite-sphene. Chemical analyses indicate the following changes during pervasive alteration of igneous rocks: (1) addition of Si, K, H, S, and Cu, and loss of Fe 3+ and Ca during intense biotitization of basalt; (2) loss of Na and Ca, increase of Fe3+/Fe2+, and strong H-metasomatism during sericitization of quartz diorite; and (3) increase in Ca, Na, and Fe3+/Fe2+, and loss of K during intense propylitization of biotite rhyodacite porphyry dikes. Thorough biotitization of biotite granodiorite porphyry in the Christmas stock was largely an isochemical process. Fluid-inclusion petrography reveals that Stage I veins are characterized by low to moderate populations of moderate-salinity and gas-rich inclusions, and sparse but ubiquitous halite-bearing inclusions. Moderate-salinity an

  15. Coarctation induces alterations in basement membranes in the cardiovascular system

    DEFF Research Database (Denmark)

    Lipke, D W; McCarthy, K J; Elton, T S

    1993-01-01

    ventricular hypertrophy was maximal within 5 days. In immunohistochemical studies, fibronectin and laminin were increased and the basement membrane chondroitin sulfate proteoglycan decreased in both the subendothelial space and smooth muscle cell basement membranes of the aorta above the clip compared...... membrane components in the heart and vasculature peaked before maximal cardiac hypertrophy (5 days). These studies indicate that alterations in basement membrane component deposition in the hypertrophied vasculature occur at both transcriptional and translational levels and suggest that the cell attachment...

  16. Alteration in the IRDP drill hole compared with other drill holes in Iceland

    Science.gov (United States)

    Kristmannsdóttir, Hrefna

    1982-08-01

    The overall alteration pattern in the drill hole at Reydarfjördur is very similar to alteration patterns observed in Icelandic geothermal areas and in low-grade metamorphosed basalts in deep crustal sections elsewhere in Iceland. However more detail is obtained by the study of the IRDP drill core than by study of drill cuttings sampled in previous drill holes in Iceland. A comparatively high fossil thermal gradient is obtained at Reydarfjördur by a combination of mineral stability data and the observed occurence of secondary minerals. This high gradient is consistent with the measured dike dilation at the drill site and the location of the drill site adjacent to a central volcano.

  17. Geochemical modeling of the influence of silicate mineral alteration on alkalinity production and carbonate precipitation

    Science.gov (United States)

    Herda, Gerhard; Kraemer, Stephan M.; Gier, Susanne; Meister, Patrick

    2016-04-01

    High CO2 partial pressure (pCO2) in deep rock reservoirs causes acidification of the porefluid. Such conditions occur during injection and subsurface storage of CO2 (to prevent the release of greenhouse gas) but also naturally in zones of strong methanogenic microbial activity in organic matter-rich ocean margin sediments. The acidic fluids are corrosive to carbonates and bear the risk of leakage of CO2 gas to the surface. Porefluid acidification may be moderated by processes that increase the alkalinity, i.e. that produce weak acid anions capable of buffering the acidification imposed by the CO2. Often, alkalinity increases as a result of anaerobic microbial activity, such as anaerobic oxidation of methane. However, on a long term the alteration of silicates, in particular, clay minerals, may be a more efficient mechanism of alkalinity production. Under altered temperature, pressure and porefluid composition at depth, clay minerals may change to thermodynamically more stable states, thereby increasing the alkalinity of the porefluid by partial leaching of Mg-(OH)2 and Ca-(OH)2 (e.g. Wallmann et al., 2008; Mavromatis et al., 2014). This alteration may even be enhanced by a high pCO2. Thus, silicate alteration can be essential for a long-term stabilization of volatile CO2 in the form of bicarbonate or may even induce precipitation of carbonate minerals, but these processes are not fully understood yet. The goal of this study is to simulate the alkalinity effect of silicate alteration under diagenetic conditions and high pCO2 by geochemical modeling. We are using the program PHREEQC (Parkhurst and Appelo, 2013) to generate high rock/fluid ratio characteristics for deep subsurface rock reservoirs. Since we are interested in the long-term evolution of diagenetic processes, over millions of years, we do not consider kinetics but calculate the theoretically possible equilibrium conditions. In a first step we are calculating the saturation state of different clay minerals

  18. Immunoendocrine alterations following Marine Corps Martial Arts training are associated with changes in moral cognitive processes.

    Science.gov (United States)

    Siedlik, Jacob A; Deckert, Jake A; Clopton, Aaron W; Gigliotti, Nicole; Chan, Marcia A; Benedict, Stephen H; Herda, Trent J; Gallagher, Philip M; Vardiman, John P

    2016-02-01

    Combined physical and psychological stress events have been associated with exacerbated endocrine responses and increased alterations in immune cell trafficking when compared to exercise stress alone. Military training programs are rigorous in nature and often purposefully delivered in environments combining high levels of both physical and mental stress. The objective of this study was to assess physiological and cognitive changes following U.S. Marine Corps Martial Arts training. Seven active-duty, male Marines were observed during a typical Marine Corps Martial Arts training session. Immune parameters, including immunomodulatory cytokines, and hormone concentrations were determined from blood samples obtained at baseline, immediately post training (IP) and at 15min intervals post-training to 1h (R15, R30, R45, R60). Assessments of cognitive moral functioning (moral judgment and intent) were recorded at intervals during recovery. There were significant fluctuations in immunoendocrine parameters. Peak endocrine measures were observed within the IP-R15 time interval. Distributions of circulating immune cells were significantly altered with neutrophils and all lymphocyte subsets elevated at IP. IFN-γ and IL-17a exhibited small, non-significant, parallel increases over the recovery period. Moral functioning was informed by different social identities during the recovery resulting in changes in moral decision-making. These data demonstrate that the Marine Corps Martial Arts Program induces significant alterations in lymphocyte and leukocyte distributions, but does not shift the balance of Th1/Th2 cytokines or induce a systemic inflammatory response. The program does, however, induce alterations in moral decision-making ability associated with the observed endocrine responses, even suggesting a potential interaction between one's social identities and endocrine responses upon moral decision-making. Copyright © 2015. Published by Elsevier Inc.

  19. Myxedema Coma Secondary to Central Hypothyroidism: A Rare but Real Cause of Altered Mental Status in Pediatrics.

    Science.gov (United States)

    Thompson, Michael D; Henry, Rohan K

    2017-01-01

    Myxedema coma (MC), a medical emergency defined as severe hypothyroidism leading to altered mental status, is more common in older women with hypothyroidism. A 7-year-old Caucasian male with chromosome 1q deletion presented with altered mental status preceded by milestone regression. His presenting labs results were: thyroid-stimulating hormone (TSH) 0.501 μIU/ml and free thyroxine (T4) <0.5 ng/dl. His morning cortisol level was 8.1 μg/dl with repeat testing, while TSH was 1.119 μIU/ml and free T4 was 0.5 ng/dl. Low-dose cosyntropin test showed baseline and peak cortisol levels of 1.9 and 16 μg/dl, respectively. Aside from altered mental status, heart block was present in addition to hypothermia and hypercarbia. Diffuse cerebral cortical and corpus callosum atrophy were seen on MRI. An intravenous (i.v.) stress dose of hydrocortisone was administered for 24 h prior to an i.v. loading dose of levothyroxine. His activity level subsequently returned to baseline within 48 h after treatment had been initiated. Though MC is rare, occurring mainly with noncompliance in primary hypothyroidism, it may occur at the diagnosis of secondary hypothyroidism. Based on features like hypothermia, hypoventilation, and cardiovascular instability occurring in the setting of central hypothyroidism, it should be suspected and managed urgently in order to avert the associated high mortality resulting from treatment delays. © 2016 S. Karger AG, Basel.

  20. Using ASD data to identify the altered minerals for exploring of gold deposit in the Beishan area, North China

    Science.gov (United States)

    Ren, G. L.; Yi, H.; Yang, M.; Liang, N.; Li, J. Q.; Yang, J. L.

    2016-11-01

    Hyperspectral information of altered minerals plays an important role in the identifications of mineralized zones. In this study, the altered minerals of two gold deposits from Fangshankou-Laojinchang regions of Beishan metallogenic belt were measured by ASD field Spectrometer. Many gold deposits would have a close relationship with Variscan magma intrusion, which have been found in study region. The alteration minerals have been divided six types by the spectral results, i.e. sericite, limonite, dolomite, chlorite, epidote and calcite. The distribution characteristics and formations of altered minerals were discussed here. By the ASD, the spectral curve of different geological units in the Jintanzi and Fangshankou gold deposits were analysed and summarized. The results show that the sericite and limonite are mainly related with the gold mineralization and widely occurred in the gold deposits. Therefore, we proposed that the sericite and limonite are the iconic alteration mineral assemblages for gold mineralization and the models of altered minerals for gold deposits could be established in this region.

  1. Altered neuronal excitability underlies impaired hippocampal function in an animal model of psychosis

    Directory of Open Access Journals (Sweden)

    Thomas eGrüter

    2015-05-01

    Full Text Available Psychosis is accompanied by severe attentional deficits, and impairments in associational-memory processing and sensory information processing that are ascribed to dysfunctions in prefrontal and hippocampal function. Disruptions of glutamatergic signalling may underlie these alterations: Antagonism of the N-methyl-D-aspartate receptor (NMDAR results in similar molecular, cellular, cognitive and behavioural changes in rodents and/or humans as those that occur in psychosis, raising the question as to whether changes in glutamatergic transmission may be intrinsic to the pathophysiology of the disease. In an animal model of psychosis that comprises treatment with the irreversible NMDAR-antagonist, MK801, we explored the cellular mechanisms that may underlie hippocampal dysfunction in psychosis. MK801-treatment resulted in a profound loss of hippocampal LTP that was evident 4 weeks after treatment. Whereas neuronal expression of the immediate early gene, Arc, was enhanced in the hippocampus by spatial learning in controls, MK801-treated animals failed to show activity-dependent increases in Arc expression. By contrast, a significant increase in basal Arc expression in the absence of learning was evident compared to controls. Paired-pulse facilitation was increased at the 40 ms interval indicating that NMDAR and/or fast GABAergic-mediated neurotransmission was disrupted. In line with this, MK801-treatment resulted in a significant decrease in GABA(A, and increase in GABA(B-receptor-expression in PFC, along with a significant increase of GABA(B- and NMDAR-GluN2B expression in the dentate gyrus. NMDAR-GluN1 or GluN2A subunit expression was unchanged. These data suggest that in psychosis, deficits in hippocampus-dependent memory may be caused by a loss of hippocampal LTP that arises through enhanced hippocampal neuronal excitability, altered GluN2B and GABA receptor expression and an uncoupling of the hippocampus-prefrontal cortex circuitry.

  2. Impact of DNA mismatch repair system alterations on human fertility and related treatments.

    Science.gov (United States)

    Hu, Min-hao; Liu, Shu-yuan; Wang, Ning; Wu, Yan; Jin, Fan

    2016-01-01

    DNA mismatch repair (MMR) is one of the biological pathways, which plays a critical role in DNA homeostasis, primarily by repairing base-pair mismatches and insertion/deletion loops that occur during DNA replication. MMR also takes part in other metabolic pathways and regulates cell cycle arrest. Defects in MMR are associated with genomic instability, predisposition to certain types of cancers and resistance to certain therapeutic drugs. Moreover, genetic and epigenetic alterations in the MMR system demonstrate a significant relationship with human fertility and related treatments, which helps us to understand the etiology and susceptibility of human infertility. Alterations in the MMR system may also influence the health of offspring conceived by assisted reproductive technology in humans. However, further studies are needed to explore the specific mechanisms by which the MMR system may affect human infertility. This review addresses the physiological mechanisms of the MMR system and associations between alterations of the MMR system and human fertility and related treatments, and potential effects on the next generation.

  3. Human diseases with genetically altered DNA repair processes

    International Nuclear Information System (INIS)

    Cleaver, J.E.; Bootsma, D.; Friedberg, E.

    1975-01-01

    DNA repair of single-strand breaks (produced by ionizing radiation) and of base damage (produced by ultraviolet (uv) light) are two repair mechanisms that most mammalian cells possess. Genetic defects in these repair mechanisms are exemplified by cells from the human premature-aging disease, progeria, which fail to rejoin single-strand breaks, and the skin disease, xeroderma pigmentosum (XP), which exhibits high actinic carcinogenesis and involves failure to repair base damage. In terms of the response of XP cells, many chemical carcinogens can be classified as either x-ray-like (i.e., they cause damage that XP cells can repair) or uv-like (i.e., they cause damage that XP cells cannot repair). The first group contains some of the more strongly carcinogenic chemicals (e.g., alkylating agents). XP occurs in at least two clinical forms, and somatic cell hybridization indicates at least three complementation groups. In order to identify cell lines from various different laboratories unambiguously, a modified nomenclature of XP lines is proposed. (U.S.)

  4. Human diseases with genetically altered DNA repair processes

    International Nuclear Information System (INIS)

    Cleaver, J.E.; Bootsma, D.; Friedberg, E.

    1975-01-01

    DNA repair of single-strand breaks (produced by ionizing radiation) and of base damage (produced by ultraviolet (UV) light) are two repair mechanisms that most mammalian cells possess. Genetic defects in these repair mechanisms are exemplified by cells from the human premature-aging disease, progeria, which fail to rejoin single-strand breaks, and the skin disease, xeroderma pigmentosum (XP), which exhibits high actinic carcinogenesis and involves failure to repair base damage. In terms of the response of XP cells, many chemical carcinogens can be classified as either X-ray-like (i.e., they cause damage that XP cells can repair) or UV-like (i.e., they cause damage that XP cells cannot repair). The first group contains some of the more strongly carcinogenic chemicals (e.g., alkylating agents). XP occurs in at least two clinical forms, and somatic cell hybridization indicates at least three complementation groups. In order to identify cell lines from various different laboratories unambiguously, a modified nomenclature of XP lines is proposed

  5. APPLICATION OF THE NATURALLY-OCCURRING DEUTERIUM ISOTOPE TO TRACING THE CAPILLARY FRINGE

    Science.gov (United States)

    Naturally-occurring deuterium is a useful tracer of subsurface hydrologic processes. A possible application includes the identification of capillary fringes in the vadose zone. Multiple and discontinuous water tables persist in many temperate regions, under various hydrogeologi...

  6. Assessment of the alteration of R7T7-type glass according to storage conditions

    International Nuclear Information System (INIS)

    Jollivet, P.; Minet, Y.; Nicolas, M.; Vernaz, E.

    1997-01-01

    The PREDIVER code was used to estimate the influence of the major parameters of a geological repository site on the alteration oh a high-level vitrified waste package. The kinetic law of glass alteration is based on a deviation concerning saturation with respect to silicic acid. Glass alteration is governed by the coefficient of silicon diffusion in the interstitial water of the gel layer and by the leachate renewal rate (i.e. the flow rate in the repository) if it is of very low magnitude. The effects of other parameters are much less significant. When applied to the alteration of natural basalts, the PREDIVER code overestimates glass alteration, indicating that transport limitations slow down the alteration processes over a long time period. (authors)

  7. Affect intensity and processing fluency of deterrents.

    Science.gov (United States)

    Holman, Andrei

    2013-01-01

    The theory of emotional intensity (Brehm, 1999) suggests that the intensity of affective states depends on the magnitude of their current deterrents. Our study investigated the role that fluency--the subjective experience of ease of information processing--plays in the emotional intensity modulations as reactions to deterrents. Following an induction phase of good mood, we manipulated both the magnitude of deterrents (using sets of photographs with pre-tested potential to instigate an emotion incompatible with the pre-existent affective state--pity) and their processing fluency (normal vs. enhanced through subliminal priming). Current affective state and perception of deterrents were then measured. In the normal processing conditions, the results revealed the cubic effect predicted by the emotional intensity theory, with the initial affective state being replaced by the one appropriate to the deterrent only in participants exposed to the high magnitude deterrence. In the enhanced fluency conditions the emotional intensity pattern was drastically altered; also, the replacement of the initial affective state occurred at a lower level of deterrence magnitude (moderate instead of high), suggesting the strengthening of deterrence emotional impact by enhanced fluency.

  8. Surface analytical techniques applied to minerals processing

    International Nuclear Information System (INIS)

    Smart, R.St.C.

    1991-01-01

    An understanding of the chemical and physical forms of the chemically altered layers on the surfaces of base metal sulphides, particularly in the form of hydroxides, oxyhydroxides and oxides, and the changes that occur in them during minerals processing lies at the core of a complete description of flotation chemistry. This paper reviews the application of a variety of surface-sensitive techniques and methodologies applied to the study of surface layers on single minerals, mixed minerals, synthetic ores and real ores. Evidence from combined XPS/SAM/SEM studies have provided images and analyses of three forms of oxide, oxyhydroxide and hydroxide products on the surfaces of single sulphide minerals, mineral mixtures and complex sulphide ores. 4 refs., 2 tabs., 4 figs

  9. Archaeological applications of naturally occurring nanomagnets

    Energy Technology Data Exchange (ETDEWEB)

    Linford, Neil [English Heritage, Fort Cumberland, Fort Cumberland Road, Eastney, Portsmouth PO4 9LD (United Kingdom)

    2005-01-01

    The ubiquitous presence of iron minerals within the soils and sediments forming archaeological sites can often provide a valuable record of past human activity. These records are formed through the alteration of weakly magnetic minerals to fine grained iron oxides, such as magnetite or maghaemite, that leave an almost indelible magnetic 'finger print' on the landscape. Archaeologists have exploited these magnetic records at a variety of levels from geophysical survey to reveal the location of a site, to determining how old a particular excavated feature may be through archaeomagnetic dating. More recent studies have investigated the process of magnetic enhancement through the often complex interaction of pedogenic, microbial and anthropogenic mechanisms and pathways. This research has revealed many unique magnetic signatures within archaeological sediments that may help to identify a range of significant environmental conditions, such as the effects of climate change or the deliberate use of fire. This paper aims to provide an overview of how the techniques of environmental magnetism may be applied to the analysis of archaeological remains. Both field based geophysical prospecting and the measurement of magnetic properties from samples recovered during excavation will be considered. The interpretation of the resulting magnetic measurements will also be addressed through the use of an unmixing algorithm applied to hysteresis data.

  10. Archaeological applications of naturally occurring nanomagnets

    International Nuclear Information System (INIS)

    Linford, Neil

    2005-01-01

    The ubiquitous presence of iron minerals within the soils and sediments forming archaeological sites can often provide a valuable record of past human activity. These records are formed through the alteration of weakly magnetic minerals to fine grained iron oxides, such as magnetite or maghaemite, that leave an almost indelible magnetic 'finger print' on the landscape. Archaeologists have exploited these magnetic records at a variety of levels from geophysical survey to reveal the location of a site, to determining how old a particular excavated feature may be through archaeomagnetic dating. More recent studies have investigated the process of magnetic enhancement through the often complex interaction of pedogenic, microbial and anthropogenic mechanisms and pathways. This research has revealed many unique magnetic signatures within archaeological sediments that may help to identify a range of significant environmental conditions, such as the effects of climate change or the deliberate use of fire. This paper aims to provide an overview of how the techniques of environmental magnetism may be applied to the analysis of archaeological remains. Both field based geophysical prospecting and the measurement of magnetic properties from samples recovered during excavation will be considered. The interpretation of the resulting magnetic measurements will also be addressed through the use of an unmixing algorithm applied to hysteresis data

  11. Naturally occurring radioactive materials (NORM) in the oil and gas processing and production facilities

    International Nuclear Information System (INIS)

    Najera F, J.

    1994-01-01

    NORM contamination is produced by concentration in petroleum facilities of naturally occurring radioactive materials. The presence of NORM in petroleum reservoirs and in the oil and gas industry has been widely recognized. It's not a critical technical problem if you proceed timely to solve it. NORM is a great but controllable hazard to the human health and the environment, and represents a severe waste management problem. We suggest to the latino american oil companies to conduct studies to detect NORM contamination in their facilities an use to them to plan the appropriate actions to control the situation. (author). 15 refs

  12. Reactive transport and mass balance modeling of the Stimson sedimentary formation and altered fracture zones constrain diagenetic conditions at Gale crater, Mars

    Science.gov (United States)

    Hausrath, E. M.; Ming, D. W.; Peretyazhko, T. S.; Rampe, E. B.

    2018-06-01

    On a planet as cold and dry as present-day Mars, evidence of multiple aqueous episodes offers an intriguing view into very different past environments. Fluvial, lacustrine, and eolian depositional environments are being investigated by the Mars Science Laboratory Curiosity in Gale crater, Mars. Geochemical and mineralogical observations of these sedimentary rocks suggest diagenetic processes affected the sediments. Here, we analyze diagenesis of the Stimson formation eolian parent material, which caused loss of olivine and formation of magnetite. Additional, later alteration in fracture zones resulted in preferential dissolution of pyroxene and precipitation of secondary amorphous silica and Ca sulfate. The ability to compare the unaltered parent material with the reacted material allows constraints to be placed on the characteristics of the altering solutions. In this work we use a combination of a mass balance approach calculating the fraction of a mobile element lost or gained, τ, with fundamental geochemical kinetics and thermodynamics in the reactive transport code CrunchFlow to examine the characteristics of multiple stages of aqueous alteration at Gale crater, Mars. Our model results indicate that early diagenesis of the Stimson sedimentary formation is consistent with leaching of an eolian deposit by a near-neutral solution, and that formation of the altered fracture zones is consistent with a very acidic, high sulfate solution containing Ca, P and Si. These results indicate a range of past aqueous conditions occurring at Gale crater, Mars, with important implications for past martian climate and environments.

  13. Detection of alteration associated with a porphyry copper deposit in southern Arizona

    Science.gov (United States)

    Abrams, M. J.; Siegal, B. S.

    1977-01-01

    Computer processing of Landsat MSS data was performed using contrast stretching and band-to-band ratioing. A false color ratio composite picture showed color anomalies which coincided with known areas of alteration on and about Red Mountain. A helicopter survey of the study area was undertaken using a portable field reflectance spectrometer. One hundred fifty-six spectra were obtained in the 0.4 to 2.5 micrometer wavelength region. The spectra were digitized, and contour maps for 24 wavelength intervals were produced; no spectral anomalies were evident for the known altered areas. A contour map produced from the 1.6 and 2.2 micrometer ratio generally delineated the alteration areas. The 1.3, 1.6, and 2.2 micrometer wavelength data were canonically transformed using a transformation empirically derived from discriminant function analysis of altered and unaltered materials for the Goldfield, Nevada region, and a contour map was produced for the first canonical variable. The known areas of alteration were clearly defined on the contour map.

  14. Co-occurring nonnative woody shrubs have additive and non-additive soil legacies.

    Science.gov (United States)

    Kuebbing, Sara E; Patterson, Courtney M; Classen, Aimée T; Simberloff, Daniel

    2016-09-01

    To maximize limited conservation funds and prioritize management projects that are likely to succeed, accurate assessment of invasive nonnative species impacts is essential. A common challenge to prioritization is a limited knowledge of the difference between the impacts of a single nonnative species compared to the impacts of nonnative species when they co-occur, and in particular predicting when impacts of co-occurring nonnative species will be non-additive. Understanding non-additivity is important for management decisions because the management of only one co-occurring invader will not necessarily lead to a predictable reduction in the impact or growth of the other nonnative plant. Nonnative plants are frequently associated with changes in soil biotic and abiotic characteristics, which lead to plant-soil interactions that influence the performance of other species grown in those soils. Whether co-occurring nonnative plants alter soil properties additively or non-additively relative to their effects on soils when they grow in monoculture is rarely addressed. We use a greenhouse plant-soil feedback experiment to test for non-additive soil impacts of two common invasive nonnative woody shrubs, Lonicera maackii and Ligustrum sinense, in deciduous forests of the southeastern United States. We measured the performance of each nonnative shrub, a native herbaceous community, and a nonnative woody vine in soils conditioned by each shrub singly or together in polyculture. Soils conditioned by both nonnative shrubs had non-additive impacts on native and nonnative performance. Root mass of the native herbaceous community was 1.5 times lower and the root mass of the nonnative L. sinense was 1.8 times higher in soils conditioned by both L. maackii and L. sinense than expected based upon growth in soils conditioned by either shrub singly. This result indicates that when these two nonnative shrubs co-occur, their influence on soils disproportionally favors persistence

  15. Rapid Thermal Processing to Enhance Steel Toughness.

    Science.gov (United States)

    Judge, V K; Speer, J G; Clarke, K D; Findley, K O; Clarke, A J

    2018-01-11

    Quenching and Tempering (Q&T) has been utilized for decades to alter steel mechanical properties, particularly strength and toughness. While tempering typically increases toughness, a well-established phenomenon called tempered martensite embrittlement (TME) is known to occur during conventional Q&T. Here we show that short-time, rapid tempering can overcome TME to produce unprecedented property combinations that cannot be attained by conventional Q&T. Toughness is enhanced over 43% at a strength level of 1.7 GPa and strength is improved over 0.5 GPa at an impact toughness of 30 J. We also show that hardness and the tempering parameter (TP), developed by Holloman and Jaffe in 1945 and ubiquitous within the field, is insufficient for characterizing measured strengths, toughnesses, and microstructural conditions after rapid processing. Rapid tempering by energy-saving manufacturing processes like induction heating creates the opportunity for new Q&T steels for energy, defense, and transportation applications.

  16. Altered Regional Cerebral Blood Flow in Chronic Whiplash Associated Disorders.

    Science.gov (United States)

    Vállez García, David; Doorduin, Janine; Willemsen, Antoon T M; Dierckx, Rudi A J O; Otte, Andreas

    2016-08-01

    There is increasing evidence of central hyperexcitability in chronic whiplash-associated disorders (cWAD). However, little is known about how an apparently simple cervical spine injury can induce changes in cerebral processes. The present study was designed (1) to validate previous results showing alterations of regional cerebral blood flow (rCBF) in cWAD, (2) to test if central hyperexcitability reflects changes in rCBF upon non-painful stimulation of the neck, and (3) to verify our hypothesis that the missing link in understanding the underlying pathophysiology could be the close interaction between the neck and midbrain structures. For this purpose, alterations of rCBF were explored in a case-control study using H2(15)O positron emission tomography, where each group was exposed to four different conditions, including rest and different levels of non-painful electrical stimulation of the neck. rCBF was found to be elevated in patients with cWAD in the posterior cingulate and precuneus, and decreased in the superior temporal, parahippocampal, and inferior frontal gyri, the thalamus and the insular cortex when compared with rCBF in healthy controls. No differences in rCBF were observed between different levels of electrical stimulation. The alterations in regions directly involved with pain perception and interoceptive processing indicate that cWAD symptoms might be the consequence of a mismatch during the integration of information in brain regions involved in pain processing. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  17. Altered Regional Cerebral Blood Flow in Chronic Whiplash Associated Disorders

    Directory of Open Access Journals (Sweden)

    David Vállez García

    2016-08-01

    Full Text Available There is increasing evidence of central hyperexcitability in chronic whiplash-associated disorders (cWAD. However, little is known about how an apparently simple cervical spine injury can induce changes in cerebral processes. The present study was designed (1 to validate previous results showing alterations of regional cerebral blood flow (rCBF in cWAD, (2 to test if central hyperexcitability reflects changes in rCBF upon non-painful stimulation of the neck, and (3 to verify our hypothesis that the missing link in understanding the underlying pathophysiology could be the close interaction between the neck and midbrain structures. For this purpose, alterations of rCBF were explored in a case-control study using H215O positron emission tomography, where each group was exposed to four different conditions, including rest and different levels of non-painful electrical stimulation of the neck. rCBF was found to be elevated in patients with cWAD in the posterior cingulate and precuneus, and decreased in the superior temporal, parahippocampal, and inferior frontal gyri, the thalamus and the insular cortex when compared with rCBF in healthy controls. No differences in rCBF were observed between different levels of electrical stimulation. The alterations in regions directly involved with pain perception and interoceptive processing indicate that cWAD symptoms might be the consequence of a mismatch during the integration of information in brain regions involved in pain processing.

  18. Meta-analysis of diffusion tensor imaging studies shows altered fractional anisotropy occurring in distinct brain areas in association with depression.

    LENUS (Irish Health Repository)

    Murphy, Melissa L

    2011-09-01

    Fractional anisotropy anomalies occurring in the white matter tracts in the brains of depressed patients may reflect microstructural changes underlying the pathophysiology of this disorder. We conducted a meta-analysis of fractional anisotropy abnormalities occurring in major depressive disorder using voxel-based diffusion tensor imaging studies. Using the Embase, PubMed and Google Scholar databases, 89 relevant data sets were identified, of which 7 (including 188 patients with major depressive disorder and 221 healthy controls) met our inclusion criteria. Authors were contacted to retrieve any additional data required. Coordinates were extracted from clusters of significant white matter fractional anisotropy differences between patients and controls. Relevant demographic, clinical and methodological variables were extracted from each study or obtained directly from authors. The meta-analysis was carried out using Signed Differential Mapping. Patients with depression showed decreased white matter fractional anisotropy values in the superior longitudinal fasciculus and increased fractional anisotropy values in the fronto-occipital fasciculus compared to controls. Using quartile and jackknife sensitivity analysis, we found that reduced fractional anisotropy in the left superior longitudinal fasciculus was very stable, with increases in the right fronto-occipital fasciculus driven by just one study. In conclusion, our meta-analysis revealed a significant reduction in fractional anisotropy values in the left superior longitudinal fasciculus, which may ultimately play an important role in the pathology of depression.

  19. Modeling Surface Processes Occurring on Moons of the Outer Solar System

    Science.gov (United States)

    Umurhan, O. M.; White, O. L.; Moore, J. M.; Howard, A. D.; Schenk, P.

    2016-12-01

    A variety of processes, some with familiar terrestrial analogs, are known to take place on moon surfaces in the outer solar system. In this talk, we discuss the observed features of mass wasting and surface transport seen on both Jupiter's moon Calisto and one of Saturn's Trojan moons Helene. We provide a number of numerical models using upgraded version of MARSSIM in support of several hypotheses suggested on behalf of the observations made regarding these objects. Calisto exhibits rolling plains of low albedo materials surrounding relatively high jutting peaks harboring high albedo deposits. Our modeling supports the interpretation that Calisto's surface is a record of erosion driven by the sublimation of CO2 and H2O contained in the bedrock. Both solar insolation and surface re-radiation drives the sublimation leaving behind debris which we interpret to be the observed darkened regolith and, further, the high albedo peaks are water ice deposits on surface cold traps. On the other hand, the 45 km scale Helene, being a milligravity environment, exhibits mysterious looking streaks and grooves of very high albedo materials extending for several kilometers with a down-sloping grade of 7o-9o. Helene's cratered terrain also shows evidence of narrowed septa. The observed surface features suggest some type of advective processes are at play in this system. Our modeling lends support to the suggestion that Helene's surface materials behave as a Bingham plastic material - our flow modeling with such rheologies can reproduce the observed pattern of streakiness depending upon the smoothness of the underlying bedrock; the overall gradients observed; and the narrowed septa of inter-crater regions.

  20. Use of airborne multispectral scanner data to map alteration related to roll-front uranium migration

    International Nuclear Information System (INIS)

    Peters, D.C.

    1983-01-01

    Computer-enhanced airborne multispectral scanner (MSS) images have been used to detect and map red oxidized alteration related to roll-front uranium migration in the southern Powder River basin, Wyoming. Information in the 0.4- to 1.1-μm spectral region was used to produce a color ratio composite image, upon which the red-altered areas can be differentiated. The red-altered and incipiently altered sandstones result from the migration of a roll-front (or geochemical cell) through the sandstone in the direction of the hydrologic gradient. Most uranium deposits in the Powder River basin occur at the boundary between this oxidized sandstone and reduced sandstone. Therefore, the ability to detect and map this alteration reliably can provide important information about the potential for uranium mineralization down gradient from the altered areas, at the surface in an area of interest. Spectral reflectance studies indicate that a shift in the absorption band edge from 0.52 μm (for goethitic sandstone) to 0.58 μm (for hematitic sandstone) and an intensification of an absorption band at 0.85 μm (for hematitic sandstone) are the bases for identifying the red-altered sandstone as green anomalous areas on the color ratio composite image. Some of the incipiently altered sandstone also appears green, whereas unaltered material and white-altered sandstone appear as blue to cyan colors. Therefore, the composite image is useful in discriminating hematitic sandstone from goethitic sandstone. At high densities (>65%), vegetation masks the sandstones on the color ratio composite image. Artemisia tridentata (sage) and Stipa comata (grass) are the species that have the greatest individual effect on the image

  1. Petrography and Mineral Chemistry of Magmatic and Hydrothermal Biotite in Porphyry Copper-Gold Deposits: A Tool for Understanding Mineralizing Fluid Compositional Changes During Alteration Processes

    OpenAIRE

    Arifudin Idrus

    2018-01-01

    DOI: 10.17014/ijog.5.1.47-64This study aims to understand the petrography and chemistry of both magmatic and hydrothermal biotites in porphyry copper-gold deposits, and to evaluate the fluid compositional changes during alteration processes. A total of 206 biotite grains from selected rock samples taken from the Batu Hijau porphyry Cu-Au deposit was analyzed. Detailed petrography and biotite chemistry analysis were performed on thin sections and polished thin sections, respectively, represent...

  2. Pediatric Obesity: Pharmacokinetic Alterations and Effects on Antimicrobial Dosing.

    Science.gov (United States)

    Natale, Stephanie; Bradley, John; Nguyen, William Huy; Tran, Tri; Ny, Pamela; La, Kirsten; Vivian, Eva; Le, Jennifer

    2017-03-01

    Limited data exist for appropriate drug dosing in obese children. This comprehensive review summarizes pharmacokinetic (PK) alterations that occur with age and obesity, and these effects on antimicrobial dosing. A thorough comparison of different measures of body weight and specific antimicrobial agents including cefazolin, cefepime, ceftazidime, daptomycin, doripenem, gentamicin, linezolid, meropenem, piperacillin-tazobactam, tobramycin, vancomycin, and voriconazole is presented. PubMed (1966-July 2015) and Cochrane Library searches were performed using these key terms: children, pharmacokinetic, obesity, overweight, body mass index, ideal body weight, lean body weight, body composition, and specific antimicrobial drugs. PK studies in obese children and, if necessary, data from adult studies were summarized. Knowledge of PK alterations stemming from physiologic changes that occur with age from the neonate to adolescent, as well as those that result from increased body fat, become an essential first step toward optimizing drug dosing in obese children. Excessive amounts of adipose tissue contribute significantly to body size, total body water content, and organ size and function that may modify drug distribution and clearance. PK studies that evaluated antimicrobial dosing primarily used total (or actual) body weight (TBW) for loading doses and TBW or adjusted body weight for maintenance doses, depending on the drugs' properties and dosing units. PK studies in obese children are imperative to elucidate drug distribution, clearance, and, consequently, the dose required for effective therapy in these children. Future studies should evaluate the effects of both age and obesity on drug dosing because the incidence of obesity is increasing in pediatric patients. © 2017 Pharmacotherapy Publications, Inc.

  3. A genetic code alteration is a phenotype diversity generator in the human pathogen Candida albicans.

    Directory of Open Access Journals (Sweden)

    Isabel Miranda

    Full Text Available BACKGROUND: The discovery of genetic code alterations and expansions in both prokaryotes and eukaryotes abolished the hypothesis of a frozen and universal genetic code and exposed unanticipated flexibility in codon and amino acid assignments. It is now clear that codon identity alterations involve sense and non-sense codons and can occur in organisms with complex genomes and proteomes. However, the biological functions, the molecular mechanisms of evolution and the diversity of genetic code alterations remain largely unknown. In various species of the genus Candida, the leucine CUG codon is decoded as serine by a unique serine tRNA that contains a leucine 5'-CAG-3'anticodon (tRNA(CAG(Ser. We are using this codon identity redefinition as a model system to elucidate the evolution of genetic code alterations. METHODOLOGY/PRINCIPAL FINDINGS: We have reconstructed the early stages of the Candida genetic code alteration by engineering tRNAs that partially reverted the identity of serine CUG codons back to their standard leucine meaning. Such genetic code manipulation had profound cellular consequences as it exposed important morphological variation, altered gene expression, re-arranged the karyotype, increased cell-cell adhesion and secretion of hydrolytic enzymes. CONCLUSION/SIGNIFICANCE: Our study provides the first experimental evidence for an important role of genetic code alterations as generators of phenotypic diversity of high selective potential and supports the hypothesis that they speed up evolution of new phenotypes.

  4. Paternal stress prior to conception alters DNA methylation and behaviour of developing rat offspring.

    Science.gov (United States)

    Mychasiuk, R; Harker, A; Ilnytskyy, S; Gibb, R

    2013-06-25

    Although there has been an abundance of research focused on offspring outcomes associated with maternal experiences, there has been limited examination of the relationship between paternal experiences and offspring brain development. As spermatogenesis is a continuous process, experiences that have the ability to alter epigenetic regulation in fathers may actually change developmental trajectories of offspring. The purpose of this study was to examine the effects of paternal stress prior to conception on behaviour and the epigenome of both male and female developing rat offspring. Male Long-Evans rats were stressed for 27 consecutive days and then mated with control female rats. Early behaviour was tested in offspring using the negative geotaxis task and the open field. At P21 offspring were sacrificed and global DNA methylation levels in the hippocampus and frontal cortex were analysed. Paternal stress prior to conception altered behaviour of all offspring on the negative geotaxis task, delaying acquisition of the task. In addition, male offspring demonstrated a reduction in stress reactivity in the open field paradigm spending more time than expected in the centre of the open field. Paternal stress also altered DNA methylation patterns in offspring at P21, global methylation was reduced in the frontal cortex of female offspring, but increased in the hippocampus of both male and female offspring. The results from this study clearly demonstrate that paternal stress during spermatogenesis can influence offspring behaviour and DNA methylation patterns, and these affects occur in a sex-dependent manner. Development takes place in the centre of a complex interaction between maternal, paternal, and environmental influences, which combine to produce the various phenotypes and individual differences that we perceive. Copyright © 2013 IBRO. Published by Elsevier Ltd. All rights reserved.

  5. Dissolution studies of natural analogues spent fuel and U(VI)-Silicon phases of and oxidative alteration process

    International Nuclear Information System (INIS)

    Perez Morales, I.

    2000-01-01

    In order to understand the long-term behavior of the nuclear spent fuel in geological repository conditions, we have performed dissolution studies with natural analogues to UO 2 as well as with solid phases representatives of the oxidative alteration pathway of uranium dioxide, as observed in both natural environment and laboratory studies. In all cases, we have studied the influence of the bicarbonate concentration in the dissolution process, as a first approximation to the groundwater composition of a granitic environment, where carbonate is one of the most important complexing agents. As a natural analogue to the nuclear spent fuel some uraninite samples from the Oklo are deposit in Gabon, where chain fission reactions took place 2000 millions years ago, as well as a pitchblende sample from the mine Fe ore deposit, in Salamanca (spain) have been studied. The studies have been performed at 25 and 60 deg C and 60 deg C, and they have focussed on the determination of both the thermodynamic and the kinetic properties of the different samples studied, using batch and continuous experimental methodologies, respectively. (Author)

  6. Metamorphism of cosmic dust: Processing from circumstellar outflows to the cometary regolith

    International Nuclear Information System (INIS)

    Nuth, J.A. III.

    1989-01-01

    Metamorphism of refractory particles continues in the interstellar medium (ISM) where the driving forces are sputtering by cosmic ray particles, annealing by high energy photons, and grain destruction in supernova generated shocks. Studies of the depletion of the elements from the gas phase of the interstellar medium tell us that if grain destruction occurs with high efficiency in the ISM, then there must be some mechanism by which grains can be formed in the ISM. Most grains in a cloud which collapses to form a star will be destroyed; many of the surviving grains will be severely processed. Grains in the outermost regions of the nebula may survive relatively unchanged by thermal processing or hydration. It is these grains which one hopes to find in comets. However, only those grains encased in ice at low temperature can be considered pristine since a considerable degree of hydrous alteration might occur in a cometary regolith if the comet enters the inner solar system. The physical, chemical and isotopic properties of a refractory grain at each stage of its life cycle will be discussed

  7. Developmental changes in reading do not alter the development of visual processing skills: An application of explanatory item response models in grades K-2

    Directory of Open Access Journals (Sweden)

    Kristi L Santi

    2015-02-01

    Full Text Available Visual processing has been widely studied in regard to its impact on a students’ ability to read. A less researched area is the role of reading in the development of visual processing skills. A cohort-sequential, accelerated-longitudinal design was utilized with 932 kindergarten, first, and second grade students to examine the impact of reading acquisition on the processing of various types of visual discrimination and visual motor test items. Students were assessed four times per year on a variety of reading measures and reading precursors and two popular measures of visual processing over a three-year period. Explanatory item response models were used to examine the roles of person and item characteristics on changes in visual processing abilities and changes in item difficulties over time. Results showed different developmental patterns for five types of visual processing test items, but most importantly failed to show consistent effects of learning to read on changes in item difficulty. Thus, the present study failed to find support for the hypothesis that learning to read alters performance on measures of visual processing. Rather, visual processing and reading ability improved together over time with no evidence to suggest cross-domain influences from reading to visual processing. Results are discussed in the context of developmental theories of visual processing and brain-based research on the role of visual skills in learning to read.

  8. Detection of random alterations to time-varying musical instrument spectra.

    Science.gov (United States)

    Horner, Andrew; Beauchamp, James; So, Richard

    2004-09-01

    The time-varying spectra of eight musical instrument sounds were randomly altered by a time-invariant process to determine how detection of spectral alteration varies with degree of alteration, instrument, musical experience, and spectral variation. Sounds were resynthesized with centroids equalized to the original sounds, with frequencies harmonically flattened, and with average spectral error levels of 8%, 16%, 24%, 32%, and 48%. Listeners were asked to discriminate the randomly altered sounds from reference sounds resynthesized from the original data. For all eight instruments, discrimination was very good for the 32% and 48% error levels, moderate for the 16% and 24% error levels, and poor for the 8% error levels. When the error levels were 16%, 24%, and 32%, the scores of musically experienced listeners were found to be significantly better than the scores of listeners with no musical experience. Also, in this same error level range, discrimination was significantly affected by the instrument tested. For error levels of 16% and 24%, discrimination scores were significantly, but negatively correlated with measures of spectral incoherence and normalized centroid deviation on unaltered instrument spectra, suggesting that the presence of dynamic spectral variations tends to increase the difficulty of detecting spectral alterations. Correlation between discrimination and a measure of spectral irregularity was comparatively low.

  9. Alterations in Striatal Circuits Underlying Addiction-Like Behaviors.

    Science.gov (United States)

    Kim, Hyun Jin; Lee, Joo Han; Yun, Kyunghwa; Kim, Joung-Hun

    2017-06-30

    Drug addiction is a severe psychiatric disorder characterized by the compulsive pursuit of drugs of abuse despite potential adverse consequences. Although several decades of studies have revealed that psychostimulant use can result in extensive alterations of neural circuits and physiology, no effective therapeutic strategies or medicines for drug addiction currently exist. Changes in neuronal connectivity and regulation occurring after repeated drug exposure contribute to addiction-like behaviors in animal models. Among the involved brain areas, including those of the reward system, the striatum is the major area of convergence for glutamate, GABA, and dopamine transmission, and this brain region potentially determines stereotyped behaviors. Although the physiological consequences of striatal neurons after drug exposure have been relatively well documented, it remains to be clarified how changes in striatal connectivity underlie and modulate the expression of addiction-like behaviors. Understanding how striatal circuits contribute to addiction-like behaviors may lead to the development of strategies that successfully attenuate drug-induced behavioral changes. In this review, we summarize the results of recent studies that have examined striatal circuitry and pathway-specific alterations leading to addiction-like behaviors to provide an updated framework for future investigations.

  10. Altered phosphorylation of rhodopsin in retinal dystrophic Irish Setters

    International Nuclear Information System (INIS)

    Cunnick, J.; Takemoto, D.J.; Takemoto, L.J.

    1986-01-01

    The carboxyl-terminus of rhodopsin in retinal dystrophic (rd) Irish Setters is altered near a possible phosphorylation site. To determine if this alteration affects ATP-mediated phosphorylation they compared the phosphorylation of rhodopsin from rd affected Irish Setters and normal unaffected dogs. Retinas from 8-week-old Irish Setters were phosphorylated with γ- 32 P-ATP and separated on SDS-PAGE. Compared to unaffected normal retinas, equalized for rhodopsin content, phosphorylation of rd rhodopsin was drastically reduced. When rd retinas were mixed with normal dog retinas, phosphorylation of the latter was inhibited. Inhibition also occurred when bovine retinas were mixed with rd retinas. The rd-mediated inhibition of phosphorylation was prevented by including 1mM NaF in the reaction mixture. Likewise, 1mM NaF restored phosphorylation of rd rhodopsin to normal levels. Phosphopeptide maps of rd and normal rhodopsin were identical and indicated 5 phosphopeptides present in each. Results suggest that one cause of the depressed rd rhodopsin phosphorylation is an increased phosphatase activity

  11. Geochemical modelling of the weathering zone of the 'Mina Fe' U deposit (Spain): A natural analogue for nuclear spent fuel alteration and stability processes in radwaste disposal

    International Nuclear Information System (INIS)

    Arcos, D.; Perez del Villar, L.; Bruno, J.; Domenech, C.

    2008-01-01

    The 'Mina Fe' U deposit (Salamanca, Spain) has been studied in the context of Enresa's programme for U-mine sites restoration and also as a natural analogue for processes in high-level nuclear waste (HLNW) geological disposal. The investigations encompassed an array of geoscience disciplines, such as structural geology, mineralogy, hydrogeology and elemental and isotopic geochemistry and hydrogeochemistry of the site. Based on the obtained results, a conceptual mineralogical and geochemical model was performed integrating the main geochemical processes occurring at the site: the interaction between oxidised and slightly acidic water with pyrite, pitchblende, calcite and dolomite, as essential minerals of the U fracture-filling mineralisation, and hydroxyapatite from the host rock, as the main source of P. This conceptual model has been tested in a systematic numerical model, which includes the main kinetic (pyrite and pitchblende dissolution) and equilibrium processes (carbonate mineral dissolution, and goethite, schoepite and autunite secondary precipitation). The results obtained from the reactive-transport model satisfactorily agree with the conceptual model previously established. The assumption of the precipitation of coffinite as a secondary mineral in the system cannot be correctly evaluated due to the lack of hydrochemical data from the reducing zone of the site and valid thermodynamic and kinetic data for this hydrated U(IV)-silicate. This precipitation can also be hampered by the probable existence of dissolved U(IV)-organic matter and/or uranyl carbonate complexes, which are thermodynamically stable under the alkaline and reducing conditions that prevail in the reducing zone of the system. Finally, the intense downwards oxic and acidic alteration in the upper part of the system is of no relevance for the performance assessment of a HLNW disposal. However, the acidic and oxidised conditions are quickly buffered to neutral-alkaline and reducing at very

  12. Mindfulness training alters emotional memory recall compared to active controls: support for an emotional information processing model of mindfulness

    Directory of Open Access Journals (Sweden)

    Doug eRoberts-Wolfe

    2012-02-01

    Full Text Available Objectives: While mindfulness-based interventions have received widespread application in both clinical and non-clinical populations, the mechanism by which mindfulness meditation improves well-being remains elusive. One possibility is that mindfulness training alters the processing of emotional information, similar to prevailing cognitive models of depression and anxiety. The aim of this study was to investigating the effects of mindfulness training on emotional information processing (i.e. memory biases in relation to both clinical symptomatology and well-being in comparison to active control conditions.Methods: Fifty-eight university students (28 female, age = 20.1 ± 2.7 years participated in either a 12-week course containing a "meditation laboratory" or an active control course with similar content or experiential practice laboratory format (music. Participants completed an emotional word recall task and self-report questionnaires of well-being and clinical symptoms before and after the 12-week course.Results: Meditators showed greater increases in positive word recall compared to controls F(1, 56 = 6.6, p = .02. The meditation group increased significantly more on measures of well-being [F(1, 56 = 6.6, p = .01], with a marginal decrease in depression and anxiety [(F(1, 56 = 3.0, p = .09] compared to controls. Increased positive word recall was associated with increased psychological well-being [r = 0.31, p = .02] and decreased clinical symptoms [r = -0.29, p = .03].Conclusion: Mindfulness training was associated with greater improvements in processing efficiency for positively valenced stimuli than active control conditions. This change in emotional information processing was associated with improvements in psychological well-being and less depression and anxiety. These data suggest that mindfulness training may improve well-being via changes in emotional information processing.

  13. The partitioning of uranium and neptunium onto hydrothermally altered concrete

    International Nuclear Information System (INIS)

    Zhao, P.; Allen, P.G.; Sylwester, E.R.; Viani, B.E.

    2000-01-01

    Partition coefficients (K d ) of U(VI) and Np(V) on untreated and hydrothermally altered concrete were measured in 0.01 M NaCl and 0.01 M NaHCO 3 solutions as functions of concentration of the radionuclides, pH, and time. The partition coefficients for both U(VI) and Np(V) on hydrothermally altered concrete are significantly lower than those on untreated concrete. The partition of both U(VI) and Np(V) are pH dependent, although the pH dependence does not appear to reflect precipitation of U and Np-bearing phases. Both sorption and precipitation are likely processes controlling partitioning of U to concrete; sorption is the most likely process controlling the partitioning of Np to concrete. The presence of 0.01 M carbonate species in solution decreases K d of U(VI) for both hydrothermally altered and untreated concrete from ≥ 10 4 mL/g to ∝ 400 to 1000 mL/g indicating a significant impact on U(VI) sorption. In contrast, the presence of carbonate only reduced the K d of Np(V) by one order of magnitude or less. X-ray absorption spectroscopy analysis of U/concrete mixtures at different pHs and times indicate that uranyl ions are partitioned as monomeric species on untreated concrete, but oligomeric species on hydrothermally altered concrete. Similar analysis of Np/concrete mixtures shows that about half of the partitioned Np(V) is reduced to Np(IV) over a period of 6 months. (orig.)

  14. On the pathologically altered pulmonary pattern

    International Nuclear Information System (INIS)

    Ginzburg, M.A.; Kinoshenko, Yu.T.

    1982-01-01

    The notions ''normal'' and ''pathologically altered pulmonary pattern'' are specified. A grouping of lung pattern alterations based on morphopathogenetic features is provided: blood and lymphatic vascular alterations, changes in the bronchi, lung stroma, and combined alterations. Radiologic appearance of the altered pulmonary pattern is classified in keeping with the basic principles of an X-ray shade examination. The terms, such as ''enriching'', ''strengthening'', ''deformation'', etc., used for describing the pathologically altered pulmonary pattern are defined

  15. Innate Immune Responses of Drosophila melanogaster Are Altered by Spaceflight

    Science.gov (United States)

    Marcu, Oana; Lera, Matthew P.; Sanchez, Max E.; Levic, Edina; Higgins, Laura A.; Shmygelska, Alena; Fahlen, Thomas F.; Nichol, Helen; Bhattacharya, Sharmila

    2011-01-01

    Alterations and impairment of immune responses in humans present a health risk for space exploration missions. The molecular mechanisms underpinning innate immune defense can be confounded by the complexity of the acquired immune system of humans. Drosophila (fruit fly) innate immunity is simpler, and shares many similarities with human innate immunity at the level of molecular and genetic pathways. The goals of this study were to elucidate fundamental immune processes in Drosophila affected by spaceflight and to measure host-pathogen responses post-flight. Five containers, each containing ten female and five male fruit flies, were housed and bred on the space shuttle (average orbit altitude of 330.35 km) for 12 days and 18.5 hours. A new generation of flies was reared in microgravity. In larvae, the immune system was examined by analyzing plasmatocyte number and activity in culture. In adults, the induced immune responses were analyzed by bacterial clearance and quantitative real-time polymerase chain reaction (qPCR) of selected genes following infection with E. coli. The RNA levels of relevant immune pathway genes were determined in both larvae and adults by microarray analysis. The ability of larval plasmatocytes to phagocytose E. coli in culture was attenuated following spaceflight, and in parallel, the expression of genes involved in cell maturation was downregulated. In addition, the level of constitutive expression of pattern recognition receptors and opsonins that specifically recognize bacteria, and of lysozymes, antimicrobial peptide (AMP) pathway and immune stress genes, hallmarks of humoral immunity, were also reduced in larvae. In adults, the efficiency of bacterial clearance measured in vivo following a systemic infection with E. coli post-flight, remained robust. We show that spaceflight altered both cellular and humoral immune responses in Drosophila and that the disruption occurs at multiple interacting pathways. PMID:21264297

  16. Innate immune responses of Drosophila melanogaster are altered by spaceflight.

    Directory of Open Access Journals (Sweden)

    Oana Marcu

    2011-01-01

    Full Text Available Alterations and impairment of immune responses in humans present a health risk for space exploration missions. The molecular mechanisms underpinning innate immune defense can be confounded by the complexity of the acquired immune system of humans. Drosophila (fruit fly innate immunity is simpler, and shares many similarities with human innate immunity at the level of molecular and genetic pathways. The goals of this study were to elucidate fundamental immune processes in Drosophila affected by spaceflight and to measure host-pathogen responses post-flight. Five containers, each containing ten female and five male fruit flies, were housed and bred on the space shuttle (average orbit altitude of 330.35 km for 12 days and 18.5 hours. A new generation of flies was reared in microgravity. In larvae, the immune system was examined by analyzing plasmatocyte number and activity in culture. In adults, the induced immune responses were analyzed by bacterial clearance and quantitative real-time polymerase chain reaction (qPCR of selected genes following infection with E. coli. The RNA levels of relevant immune pathway genes were determined in both larvae and adults by microarray analysis. The ability of larval plasmatocytes to phagocytose E. coli in culture was attenuated following spaceflight, and in parallel, the expression of genes involved in cell maturation was downregulated. In addition, the level of constitutive expression of pattern recognition receptors and opsonins that specifically recognize bacteria, and of lysozymes, antimicrobial peptide (AMP pathway and immune stress genes, hallmarks of humoral immunity, were also reduced in larvae. In adults, the efficiency of bacterial clearance measured in vivo following a systemic infection with E. coli post-flight, remained robust. We show that spaceflight altered both cellular and humoral immune responses in Drosophila and that the disruption occurs at multiple interacting pathways.

  17. Model calculations of the chemical processes occurring in the plume of a coal-fired power plant

    Energy Technology Data Exchange (ETDEWEB)

    Meagher, J F; Luria, M

    1982-02-01

    Computer simulations of the homogeneous, gas phase chemical reactions which occur in the plume of a coal-fired power plant were conducted in an effort to understand the influence of various environmental parameters on the production of secondary pollutants. Input data for the model were selected to reproduce the dilution of a plume from a medium-sized power plant. The environmental conditions chosen were characteristic of those found during mid-August in the south-eastern United States. Under most conditions examined, it was found that hydroxyl radicals were the most important species in the homogeneous conversion of stack gases into secondary pollutants. Other free radicals, such as HO/sub 2/ and CH/sub 3/O/sub 2/, exceeded the contribution of HO radicals only when high background hydrocarbon concentrations are used. The conversion rates calculated for the oxidation of SO/sub 2/ to SO/sub 4//sup 2 -/ in these plumes were consistent with those determined experimentally. The concentrations and relative proportions of NO/sub x/ (from the power plant) and reactive hydrocarbons (from the background air) determine, to a large extent, the plume reactivity. Free radical production is suppressed during the initial stages of dilution due to the high NO/sub x/ levels. Significant dilution is required before a suitable mix is attained which can sustain the free radical chain processes common to smog chemistry. In most cases, the free radical concentrations were found to pass through maxima and return to background levels. Under typical summertime conditions, the hyroxyl radical concentration was found to reach a maximum at a HC/NO/sub x/ ratio of approximately 20.

  18. Alteration of the digestive motility linked with radiation-induced inflammatory processes in rats

    International Nuclear Information System (INIS)

    Picard, C.

    2000-12-01

    Exposure to ionizing radiation, whether accidental or for medical reasons, may lead to gastro-intestinal injury, characterized by nausea, vomiting, diarrhea and abdominal cramps. The aetiology of radiation-induced diarrhea remains to date unclear. In this study, we have investigated the acute effects of a 10 Gy abdominal irradiation on rat digestive functions. The objective of the first study was to evaluate the role of sensory afferent neurons, capsaicin-sensitive, on morphological changes and the inflammatory response following exposure. Three days after irradiation, we observed an inflammatory response characterized by neutrophils infiltration and mast cells de-granulation. No effect of capsaicin pre-treatment was seen on these parameters. However, neutrophils infiltration was increased as early as one day after irradiation in capsaicin-treated rats. No difference in severity of diarrhea was observed after denervation nor in morphological changes. These data demonstrate that abdominal irradiation results in diarrhea concomitant with an inflammatory response, and that sensory innervation does not play a major protective role. The objective of the rest of the work was in the first instance to characterize radiation-induced alterations of intestinal and colonic motility leading to diarrhea and secondly to evaluate the role of serotonin in such disorders. Perturbations in intestinal (MMC) and colonic (LSB) motor profiles were observed from the first day onwards. Migrating motor complexes (MMC) were completely disrupted at three days at the same time as the onset of diarrhea. In addition to inhibition of LSB, colonic fluid absorptive capacity was decreased and serotonin colonic tissue levels were increased three days after irradiation. Radiation-induced diarrhea was reduced by treatment with an antagonist of 5-HT 3 receptors, granisetron, as were alterations of colonic motility and serotonin tissue levels. However, this treatment did not significantly ameliorate

  19. The surfactant protein C mutation A116D alters cellular processing, stress tolerance, surfactant lipid composition, and immune cell activation

    Directory of Open Access Journals (Sweden)

    Zarbock Ralf

    2012-03-01

    Full Text Available Abstract Background Surfactant protein C (SP-C is important for the function of pulmonary surfactant. Heterozygous mutations in SFTPC, the gene encoding SP-C, cause sporadic and familial interstitial lung disease (ILD in children and adults. Mutations mapping to the BRICHOS domain located within the SP-C proprotein result in perinuclear aggregation of the proprotein. In this study, we investigated the effects of the mutation A116D in the BRICHOS domain of SP-C on cellular homeostasis. We also evaluated the ability of drugs currently used in ILD therapy to counteract these effects. Methods SP-CA116D was expressed in MLE-12 alveolar epithelial cells. We assessed in vitro the consequences for cellular homeostasis, immune response and effects of azathioprine, hydroxychloroquine, methylprednisolone and cyclophosphamide. Results Stable expression of SP-CA116D in MLE-12 alveolar epithelial cells resulted in increased intracellular accumulation of proSP-C processing intermediates. SP-CA116D expression further led to reduced cell viability and increased levels of the chaperones Hsp90, Hsp70, calreticulin and calnexin. Lipid analysis revealed decreased intracellular levels of phosphatidylcholine (PC and increased lyso-PC levels. Treatment with methylprednisolone or hydroxychloroquine partially restored these lipid alterations. Furthermore, SP-CA116D cells secreted soluble factors into the medium that modulated surface expression of CCR2 or CXCR1 receptors on CD4+ lymphocytes and neutrophils, suggesting a direct paracrine effect of SP-CA116D on neighboring cells in the alveolar space. Conclusions We show that the A116D mutation leads to impaired processing of proSP-C in alveolar epithelial cells, alters cell viability and lipid composition, and also activates cells of the immune system. In addition, we show that some of the effects of the mutation on cellular homeostasis can be antagonized by application of pharmaceuticals commonly applied in ILD therapy

  20. Using Multiscale Modeling to Study Coupled Flow, Transport, Reaction and Biofilm Growth Processes in Porous Media

    Science.gov (United States)

    Valocchi, A. J.; Laleian, A.; Werth, C. J.

    2017-12-01

    Perturbation of natural subsurface systems by fluid inputs may induce geochemical or microbiological reactions that change porosity and permeability, leading to complex coupled feedbacks between reaction and transport processes. Some examples are precipitation/dissolution processes associated with carbon capture and storage and biofilm growth associated with contaminant transport and remediation. We study biofilm growth due to mixing controlled reaction of multiple substrates. As biofilms grow, pore clogging occurs which alters pore-scale flow paths thus changing the mixing and reaction. These interactions are challenging to quantify using conventional continuum-scale porosity-permeability relations. Pore-scale models can accurately resolve coupled reaction, biofilm growth and transport processes, but modeling at this scale is not feasible for practical applications. There are two approaches to address this challenge. Results from pore-scale models in generic pore structures can be used to develop empirical relations between porosity and continuum-scale parameters, such as permeability and dispersion coefficients. The other approach is to develop a multiscale model of biofilm growth in which non-overlapping regions at pore and continuum spatial scales are coupled by a suitable method that ensures continuity of flux across the interface. Thus, regions of high reactivity where flow alteration occurs are resolved at the pore scale for accuracy while regions of low reactivity are resolved at the continuum scale for efficiency. This approach thus avoids the need for empirical upscaling relations in regions with strong feedbacks between reaction and porosity change. We explore and compare these approaches for several two-dimensional cases.

  1. Intra-strain polymorphisms are detected but no genomic alteration is found in cloned mice

    International Nuclear Information System (INIS)

    Gotoh, Koshichi; Inoue, Kimiko; Ogura, Atsuo; Oishi, Michio

    2006-01-01

    In-gel competitive reassociation (IGCR) is a method for differential subtraction of polymorphic (RFLP) DNA fragments between two DNA samples of interest without probes or specific sequence information. Here, we applied the IGCR procedure to two cloned mice derived from an F1 hybrid of the C57BL/6Cr and DBA/2 strains, in order to investigate the possibility of genomic alteration in the cloned mouse genomes. Each of the five of the genomic alterations we detected between the two cloned mice corresponded to the 'intra-strain' polymorphisms in the C57BL/6Cr and DBA/2 mouse strains. Our result suggests that no severe aberration of genome sequences occurs due to somatic cell nuclear transfer

  2. Altered ganglioside GD3 in HeLa cells might influence the cytotoxic abilities of NK cells

    OpenAIRE

    Lee, Wen-Chi; Lee, Wen-Ling; Shyong, Wen-Yuann; Yang, Lin-Wei; Ko, Min-Chun; Yeh, Chang-Ching; Edmond Hsieh, Shie-Liang; Wang, Peng-Hui

    2012-01-01

    Objective: Previously, we found that altered sialidases in HeLa cells in a natural killer-HeLa (NK-HeLa) coculture system contributed to the decreased cytotoxic ability of NK cells. However, changes that occur in the glycosylation of the HeLa cells in the NK-HeLa coculture system remain unknown. Materials and Methods: An NK-HeLa coculture system was used to examine the changes that occur in the gangliosides of HeLa cells. Results: GD3 expression in HeLa cells was significantly increased...

  3. Evolution and clinical impact of co-occurring genetic alterations in advanced-stage EGFR-mutant lung cancers. | Office of Cancer Genomics

    Science.gov (United States)

    A widespread approach to modern cancer therapy is to identify a single oncogenic driver gene and target its mutant-protein product (for example, EGFR-inhibitor treatment in EGFR-mutant lung cancers). However, genetically driven resistance to targeted therapy limits patient survival. Through genomic analysis of 1,122 EGFR-mutant lung cancer cell-free DNA samples and whole-exome analysis of seven longitudinally collected tumor samples from a patient with EGFR-mutant lung cancer, we identified critical co-occurring oncogenic events present in most advanced-stage EGFR-mutant lung cancers.

  4. Surviving endoplasmic reticulum stress is coupled to altered chondrocyte differentiation and function.

    Directory of Open Access Journals (Sweden)

    Kwok Yeung Tsang

    2007-03-01

    Full Text Available In protein folding and secretion disorders, activation of endoplasmic reticulum (ER stress signaling (ERSS protects cells, alleviating stress that would otherwise trigger apoptosis. Whether the stress-surviving cells resume normal function is not known. We studied the in vivo impact of ER stress in terminally differentiating hypertrophic chondrocytes (HCs during endochondral bone formation. In transgenic mice expressing mutant collagen X as a consequence of a 13-base pair deletion in Col10a1 (13del, misfolded alpha1(X chains accumulate in HCs and elicit ERSS. Histological and gene expression analyses showed that these chondrocytes survived ER stress, but terminal differentiation is interrupted, and endochondral bone formation is delayed, producing a chondrodysplasia phenotype. This altered differentiation involves cell-cycle re-entry, the re-expression of genes characteristic of a prehypertrophic-like state, and is cell-autonomous. Concomitantly, expression of Col10a1 and 13del mRNAs are reduced, and ER stress is alleviated. ERSS, abnormal chondrocyte differentiation, and altered growth plate architecture also occur in mice expressing mutant collagen II and aggrecan. Alteration of the differentiation program in chondrocytes expressing unfolded or misfolded proteins may be part of an adaptive response that facilitates survival and recovery from the ensuing ER stress. However, the altered differentiation disrupts the highly coordinated events of endochondral ossification culminating in chondrodysplasia.

  5. Study of nuclear glasses alteration gel and synthesis of some model gels; Etude du gel d`alteration des verres nucleaires et synthese de gels modeles

    Energy Technology Data Exchange (ETDEWEB)

    Ricol, S

    1995-10-05

    This work deals with the general problem of alteration of the reference nuclear glass R7T7. Attention is paid particularly to the altered layer formed at the glass surface during alteration process. In opposition to previous works, related essentially to glass dissolution kinetics based on chemical analyses of lixiviated elements, this thesis deals with alteration problems through structural studies of the reference glass and derived gel. This approach allows the determination of mechanisms for the gel formation and a better understanding of the behaviour of glasses towards lixiviation. Both approaches appeared complementary. Based on several spectroscopic techniques, this work showed the particular role of cations such as calcium, zirconium and iron. Studies of silica-based synthetic gels showed the synergic effect of formers cation and of one highly coordinated cation. The variation of the wavenumber related to Si-O-Si asymmetric stretching vibration can be correlated to O/Si ratio for ternary systems Si/Na/Zr. On the contrary, the Si losses of the materials depend on the number of non-bridging oxygen atoms. In the perspective of long-term behaviour, the alteration gel presents better characteristics than initial glass. It is therefore a highly stable material in static conditions. In the same way, synthetic gels are materials with very low solubilities (much lower than the alteration gel) and could be used as confining matrices. (authors). refs., 71 figs., 37 tabs.

  6. Altered carbon dioxide metabolism and creatine abnormalities in rett syndrome

    NARCIS (Netherlands)

    Halbach, Nicky S J; Smeets, Eric E J; Bierau, Jörgen; Keularts, Irene M L W; Plasqui, Guy; Julu, Peter O O; Engerström, Ingegerd Witt; Bakker, Jaap A.; Curfs, Leopold M G

    2012-01-01

    Despite their good appetite, many females with Rett syndrome (RTT) meet the criteria for moderate to severe malnutrition. Although feeding difficulties may play a part in this, other constitutional factors such as altered metabolic processes are suspected. Irregular breathing is a common clinical

  7. X-Ray Amorphous Phases in Antarctica Dry Valley Soils: Insight into Aqueous Alteration Processes on Mars?

    Science.gov (United States)

    Ming, D. W.; Morris, R. V.; Rampe, E. B.; Golden, D. C.; Quinn, J. E.

    2015-01-01

    may have been physically and chemical altered during soil formation, however, the limited interaction with water and low temperatures may result in the formation of "immature" X-ray amorphous or SRO materials. Perhaps, a similar process contributes to the formation of the high content of X-ray amorphous materials detected on Mars.

  8. Numerical and experimental study on the ability of dynamic roughness to alter the development of a leading edge vortex

    Science.gov (United States)

    Griffin, Christopher D.

    Dynamic stall is an unsteady aerodynamic phenomenon garnering much research interest because it occurs in a variety of applications. For example, dynamic stall is known to occur on helicopter rotor blades, wind turbines, high maneuvering military aircraft, and flapping wings. Dynamic stall occurs when an aerodynamic lifting device, such as an airfoil, wing, or turbomachine blade, undergoes a rapid pitching motion. It also occurs on lifting devices that are impulsively started at high angles of attack. Dynamic stall can "delay" aerodynamic stall to angles of attack that are significantly beyond the static stall angle of attack. During dynamic stall a large leading edge vortex (LEV) is formed, which creates greater fluid acceleration over the wing or airfoil, thus sustaining lift. As this vortex is shed downstream stall eventually occurs and there is an abrupt increase in drag and a large shift in pitching moment. Research has been performed to better understand the mechanisms occurring during dynamic stall in an effort to find ways to best take advantage of the increased lift associated with dynamic stall, but avoid the downfalls that occur once stall is initiated. Few attempts have been made to alter the LEV, and these attempts have used methods associated with laminar boundary layer separation control. Although these methods have shown promise, they suffer from the drawback that they exhaust more energy than is gained by flow control, while also only being effective at certain flight regimes. The research described herein documents the first study on the ability of dynamic roughness to alter the LEV encountered on a rapidly pitching airfoil. Both numerical and experimental studies were performed, including two-dimensional and three-dimensional computational fluid dynamics (CFD) simulations as well as stereo and planar particle image velocimetry (PIV) experiments. Evidence for the ability of small scale dynamic roughness to alter the development of the LEV was

  9. Sequestration of DROSHA and DGCR8 by Expanded CGG RNA Repeats Alters MicroRNA Processing in Fragile X-Associated Tremor/Ataxia Syndrome

    Directory of Open Access Journals (Sweden)

    Chantal Sellier

    2013-03-01

    Full Text Available Fragile X-associated tremor/ataxia syndrome (FXTAS is an inherited neurodegenerative disorder caused by the expansion of 55–200 CGG repeats in the 5′ UTR of FMR1. These expanded CGG repeats are transcribed and accumulate in nuclear RNA aggregates that sequester one or more RNA-binding proteins, thus impairing their functions. Here, we have identified that the double-stranded RNA-binding protein DGCR8 binds to expanded CGG repeats, resulting in the partial sequestration of DGCR8 and its partner, DROSHA, within CGG RNA aggregates. Consequently, the processing of microRNAs (miRNAs is reduced, resulting in decreased levels of mature miRNAs in neuronal cells expressing expanded CGG repeats and in brain tissue from patients with FXTAS. Finally, overexpression of DGCR8 rescues the neuronal cell death induced by expression of expanded CGG repeats. These results support a model in which a human neurodegenerative disease originates from the alteration, in trans, of the miRNA-processing machinery.

  10. Hydrothermal Alteration in an Acid-Sulphate Geothermal Field: Sulphur Springs, Saint Lucia

    Science.gov (United States)

    Joseph, E. P.; Barrett, T. J.

    2017-12-01

    Sulphur Springs is a vigorous geothermal field associated with the Soufrière Volcanic Centre in southern Saint Lucia. Bubbling hydrothermal pools are rich in sodium-calcium sulphate, with pHs of 3-7 and temperatures of 41-97ºC. Fumaroles have temperatures up to, and at times above, 100°C. Gases from bubbling pools and fumaroles have high contents of CO2 (601-993 mmol/mol) and H2S (3-190 mmol/mol). To investigate the nature and extent of hydrothermal alteration, detailed chemical analysis was carried out on 25 altered rocks, 10 sediments from pools and creeks in the main discharge area, and 15 little-altered rocks up to 2 km away from geothermal field. Eight altered samples were also analysed for stable isotope compositions, with mineralogy determined by X-ray diffraction and mineral liberation analysis. Least-altered host rocks comprise calc-alkaline feldspar-quartz-porphyritic dacites of near-uniform composition that form massive domes and volcaniclastic units. These rocks were emplaced 10-30 Ka ago (Lindsay et al. 2013). Within the geothermal field, the dacites have been highly altered to kaolinite, quartz, cristobalite, alunite, natroalunite, smectite, native sulphur, jarosite, gypsum and amorphous compounds. Muds from grey to blackish hydrothermal pools additionally contain iron sulphides, mainly pyrite. Despite intense alteration of the original dacites, Zr and Ti have remained essentially immobile, allowing the calculation of mass changes. Major depletions of Fe, Mg, Ca, Na and commonly Si occur over an area of at least 200 x 400 m. The most altered rocks also show losses of Al, light REE and Y, implying leaching by highly acidic waters. A few altered rocks have, however, gained Al together with Si and P. Also present are m-scale zones of silica + native sulphur, wherein the silica appears to represent a residue from the leaching of dacite, rather than a hydrothermal addition. Delta-34S values of samples containing mixtures of sulphates, native sulphur and

  11. Hydrothermal alteration in oceanic ridge volcanics: A detailed study at the Galapagos Fossil Hydrothermal Field

    Science.gov (United States)

    Ridley, W.I.; Perfit, M.R.; Josnasson, I.R.; Smith, M.F.

    1994-01-01

    The Galapagos Fossil Hydrothermal Field is composed of altered oceanic crust and extinct hydrothermal vents within the eastern Galapagos Rift between 85??49???W and 85??55???W. The discharge zone of the hydrothermal system is revealed along scarps, thus providing an opportunity to examine the uppermost mineralized, and highly altered interior parts of the crust. Altered rocks collected in situ by the submersible ALVIN show complex concentric alteration zones. Microsamples of individual zones have been analysed for major/minor, trace elements, and strontium isotopes in order to describe the complex compositional details of the hydrothermal alteration. Interlayered chlorite-smectite and chlorite with disequilibrium compositions dominate the secondary mineralogy as replacement phases of primary glass and acicular pyroxene. Phenocrysts and matrix grains of plagioclase are unaffected during alteration. Using a modification of the Gresens' equation we demonstrate that the trivalent rare earth elements (REEs) are relatively immobile, and calculate degrees of enrichment and depletion in other elements. Strontium isotopic ratios increase as Sr concentrations decrease from least-altered cores to most-altered rims and cross-cutting veins in individual samples, and can be modeled by open system behaviour under low fluid-rock ratio (< 10) conditions following a period of lower-temperature weathering of volcanics within the rift zone. The complex patterns of element enrichment and depletion and strontium isotope variations indicate mixing between pristine seawater and ascending hot fluids to produce a compositional spectrum of fluids. The precipitation of base-metal sulfides beneath the seafloor is probably a result of fluid mixing and cooling. If, as suggested here, the discharge zone alteration occurred under relatively low fluid-rock ratios, then this shallow region must play an important role in determining the exit composition of vent fluids in marine hydrothermal systems

  12. [Colorectal cancer (CCR): genetic and molecular alterations].

    Science.gov (United States)

    Juárez-Vázquez, Clara Ibet; Rosales-Reynoso, Mónica Alejandra

    2014-01-01

    The aim of this review is to present a genetic and molecular overview of colorectal carcinogenesis (sporadic and hereditary origin) as a multistage process, where there are a number of molecular mechanisms associated with the development of colorectal cancer and genomic instability that allows the accumulation of mutations in proto-oncogenes and tumor suppressor genes, chromosomal instability, and methylation and microsatellite instability, and the involvement of altered expression of microRNAs' prognosis factors.

  13. Genetic basis of hindlimb loss in a naturally occurring vertebrate model

    Directory of Open Access Journals (Sweden)

    Emily K. Don

    2016-03-01

    Full Text Available Here we genetically characterise pelvic finless, a naturally occurring model of hindlimb loss in zebrafish that lacks pelvic fin structures, which are homologous to tetrapod hindlimbs, but displays no other abnormalities. Using a hybrid positional cloning and next generation sequencing approach, we identified mutations in the nuclear localisation signal (NLS of T-box transcription factor 4 (Tbx4 that impair nuclear localisation of the protein, resulting in altered gene expression patterns during pelvic fin development and the failure of pelvic fin development. Using a TALEN-induced tbx4 knockout allele we confirm that mutations within the Tbx4 NLS (A78V; G79A are sufficient to disrupt pelvic fin development. By combining histological, genetic, and cellular approaches we show that the hindlimb initiation gene tbx4 has an evolutionarily conserved, essential role in pelvic fin development. In addition, our novel viable model of hindlimb deficiency is likely to facilitate the elucidation of the detailed molecular mechanisms through which Tbx4 functions during pelvic fin and hindlimb development.

  14. Enamel alteration following tooth bleaching and remineralization.

    Science.gov (United States)

    Coceska, Emilija; Gjorgievska, Elizabeta; Coleman, Nichola J; Gabric, Dragana; Slipper, Ian J; Stevanovic, Marija; Nicholson, John W

    2016-06-01

    The purpose of this study was to compare the effects of professional tooth whitening agents containing highly concentrated hydrogen peroxide (with and without laser activation), on the enamel surface; and the potential of four different toothpastes to remineralize any alterations. The study was performed on 50 human molars, divided in two groups: treated with Opalescence(®) Boost and Mirawhite(®) Laser Bleaching. Furthermore, each group was divided into five subgroups, a control one and 4 subgroups remineralized with: Mirasensitive(®) hap+, Mirawhite(®) Gelleѐ, GC Tooth Mousse™ and Mirafluor(®) C. The samples were analysed by SEM/3D-SEM-micrographs, SEM/EDX-qualitative analysis and SEM/EDX-semiquantitative analysis. The microphotographs show that both types of bleaching cause alterations: emphasized perikymata, erosions, loss of interprizmatic substance; the laser treatment is more aggressive and loss of integrity of the enamel is determined by shearing off the enamel rods. In all samples undergoing remineralization deposits were observed, those of toothpastes based on calcium phosphate technologies seem to merge with each other and cover almost the entire surface of the enamel. Loss of integrity and minerals were detected only in the line-scans of the sample remineralized with GC Tooth Mousse™. The semiquantitative EDX analysis of individual elements in the surface layer of the enamel indicates that during tooth-bleaching with HP statistically significant loss of Na and Mg occurs, whereas the bleaching in combination with a laser leads to statistically significant loss of Ca and P. The results undoubtedly confirm that teeth whitening procedures lead to enamel alterations. In this context, it must be noted that laser bleaching is more aggressive for dental substances. However, these changes are reversible and can be repaired by application of remineralization toothpastes. © 2015 The Authors Journal of Microscopy © 2015 Royal Microscopical Society.

  15. Genomic and Epigenomic Alterations in Cancer.

    Science.gov (United States)

    Chakravarthi, Balabhadrapatruni V S K; Nepal, Saroj; Varambally, Sooryanarayana

    2016-07-01

    Multiple genetic and epigenetic events characterize tumor progression and define the identity of the tumors. Advances in high-throughput technologies, like gene expression profiling, next-generation sequencing, proteomics, and metabolomics, have enabled detailed molecular characterization of various tumors. The integration and analyses of these high-throughput data have unraveled many novel molecular aberrations and network alterations in tumors. These molecular alterations include multiple cancer-driving mutations, gene fusions, amplification, deletion, and post-translational modifications, among others. Many of these genomic events are being used in cancer diagnosis, whereas others are therapeutically targeted with small-molecule inhibitors. Multiple genes/enzymes that play a role in DNA and histone modifications are also altered in various cancers, changing the epigenomic landscape during cancer initiation and progression. Apart from protein-coding genes, studies are uncovering the critical regulatory roles played by noncoding RNAs and noncoding regions of the genome during cancer progression. Many of these genomic and epigenetic events function in tandem to drive tumor development and metastasis. Concurrent advances in genome-modulating technologies, like gene silencing and genome editing, are providing ability to understand in detail the process of cancer initiation, progression, and signaling as well as opening up avenues for therapeutic targeting. In this review, we discuss some of the recent advances in cancer genomic and epigenomic research. Copyright © 2016 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  16. Hydrothermal alteration and diagenesis of terrestrial lacustrine pillow basalts: Coordination of hyperspectral imaging with laboratory measurements

    Science.gov (United States)

    Greenberger, Rebecca N.; Mustard, John F.; Cloutis, Edward A.; Mann, Paul; Wilson, Janette H.; Flemming, Roberta L.; Robertson, Kevin M.; Salvatore, Mark R.; Edwards, Christopher S.

    2015-12-01

    We investigate an outcrop of ∼187 Ma lacustrine pillow basalts of the Talcott Formation exposed in Meriden, Connecticut, USA, focusing on coordinated analyses of one pillow lava to characterize the aqueous history of these basalts in the Hartford Basin. This work uses a suite of multidisciplinary measurements, including hyperspectral imaging, other spectroscopic techniques, and chemical and mineralogical analyses, from the microscopic scale up to the scale of an outcrop. The phases identified in the sample are albite, large iron oxides, and titanite throughout; calcite in vesicles; calcic clinopyroxene, aegirine, and Fe/Mg-bearing clay in the rind; and fine-grained hematite and pyroxenes in the interior. Using imaging spectroscopy, the chemistry and mineralogy results extend to the hand sample and larger outcrop. From all of the analyses, we suggest that the pillow basalts were altered initially after emplacement, either by heated lake water or magmatic fluids, at temperatures of at least 400-600 °C, and the calcic clinopyroxenes and aegirine identified in the rind are a preserved record of that alteration. As the hydrothermal system cooled to slightly lower temperatures, clays formed in the rind, and, during this alteration, the sample oxidized to form hematite in the matrix of the interior and Fe3+ in the pyroxenes in the rind. During the waning stages of the hydrothermal system, calcite precipitated in vesicles within the rind. Later, diagenetic processes albitized the sample, with albite replacing plagioclase, lining vesicles, and accreting onto the exterior of the sample. This albitization or Na-metasomatism occurred when the lake within the Hartford Basin evaporated during a drier past climatic era, resulting in Na-rich brines. As Ca-rich plagioclase altered to albite, Ca was released into solution, eventually precipitating as calcite in previously-unfilled vesicles, dominantly in the interior of the pillow. Coordinated analyses of this sample permit

  17. Modeling of biopharmaceutical processes. Part 2: Process chromatography unit operation

    DEFF Research Database (Denmark)

    Kaltenbrunner, Oliver; McCue, Justin; Engel, Philip

    2008-01-01

    Process modeling can be a useful tool to aid in process development, process optimization, and process scale-up. When modeling a chromatography process, one must first select the appropriate models that describe the mass transfer and adsorption that occurs within the porous adsorbent. The theoret......Process modeling can be a useful tool to aid in process development, process optimization, and process scale-up. When modeling a chromatography process, one must first select the appropriate models that describe the mass transfer and adsorption that occurs within the porous adsorbent...

  18. Petrography and mineralogy of alteration halos around the Cigar Lake deposit and their relation to the mineralization

    International Nuclear Information System (INIS)

    Pacquet, A.; Weber, F.

    1993-01-01

    Around the Cigar Lake orebody, the present zoneography of alteration halos reflects several alteration episodes, some of which are anterior to and others coeval with the mineralizing events and have a regional extension. In the main pod, the uraninite mineralization was dated 1341 ± 12 Ma. In the sandstones, it is surrounded by ferromagnesian chlorites with a variable sudoitic character. This proximal alteration halo grades into a more distal envelope, visible in the sandstone and in the basement, that is composed of magnesium sudoite and 3T hydromuscovite. During this mineralizing event, dravite crystallized in the form of urchin-like clusters in the basement and xenotime overgrowth, around altered zircon, and apatite formed in the sandstones. Around the main pod and in some perched orebodies, an alteration zone of vanadium-bearing ferrikaolinite and iron-bearing 3T hydromuscovite, crosscut by a later siderite, surrounds the pitchblende dated 323 ± 4 Ma. Coffinite and an aluminous hydromuscovite crystallized during a later fracture event. The aluminous hydromuscovite also appears, with a silica-carbon-uranium complex, in perched mineralizations. Kaolinization and iron-sulfide oxidation into iron hydroxides occurred in perched orebodies that were more exposed to meteoric alteration. 19 refs., 12 figs., 11 tabs [fr

  19. Altered resting brain function and structure in professional badminton players.

    Science.gov (United States)

    Di, Xin; Zhu, Senhua; Jin, Hua; Wang, Pin; Ye, Zhuoer; Zhou, Ke; Zhuo, Yan; Rao, Hengyi

    2012-01-01

    Neuroimaging studies of professional athletic or musical training have demonstrated considerable practice-dependent plasticity in various brain structures, which may reflect distinct training demands. In the present study, structural and functional brain alterations were examined in professional badminton players and compared with healthy controls using magnetic resonance imaging (MRI) and resting-state functional MRI. Gray matter concentration (GMC) was assessed using voxel-based morphometry (VBM), and resting-brain functions were measured by amplitude of low-frequency fluctuation (ALFF) and seed-based functional connectivity. Results showed that the athlete group had greater GMC and ALFF in the right and medial cerebellar regions, respectively. The athlete group also demonstrated smaller ALFF in the left superior parietal lobule and altered functional connectivity between the left superior parietal and frontal regions. These findings indicate that badminton expertise is associated with not only plastic structural changes in terms of enlarged gray matter density in the cerebellum, but also functional alterations in fronto-parietal connectivity. Such structural and functional alterations may reflect specific experiences of badminton training and practice, including high-capacity visuo-spatial processing and hand-eye coordination in addition to refined motor skills.

  20. Unique mutation portraits and frequent COL2A1 gene alteration in chondrosarcoma

    Science.gov (United States)

    Totoki, Yasushi; Yoshida, Akihiko; Hosoda, Fumie; Nakamura, Hiromi; Hama, Natsuko; Ogura, Koichi; Yoshida, Aki; Fujiwara, Tomohiro; Arai, Yasuhito; Toguchida, Junya; Tsuda, Hitoshi; Miyano, Satoru; Kawai, Akira

    2014-01-01

    Chondrosarcoma is the second most frequent malignant bone tumor. However, the etiological background of chondrosarcomagenesis remains largely unknown, along with details on molecular alterations and potential therapeutic targets. Massively parallel paired-end sequencing of whole genomes of 10 primary chondrosarcomas revealed that the process of accumulation of somatic mutations is homogeneous irrespective of the pathological subtype or the presence of IDH1 mutations, is unique among a range of cancer types, and shares significant commonalities with that of prostate cancer. Clusters of structural alterations localized within a single chromosome were observed in four cases. Combined with targeted resequencing of additional cartilaginous tumor cohorts, we identified somatic alterations of the COL2A1 gene, which encodes an essential extracellular matrix protein in chondroskeletal development, in 19.3% of chondrosarcoma and 31.7% of enchondroma cases. Epigenetic regulators (IDH1 and YEATS2) and an activin/BMP signal component (ACVR2A) were recurrently altered. Furthermore, a novel FN1-ACVR2A fusion transcript was observed in both chondrosarcoma and osteochondromatosis cases. With the characteristic accumulative process of somatic changes as a background, molecular defects in chondrogenesis and aberrant epigenetic control are primarily causative of both benign and malignant cartilaginous tumors. PMID:25024164

  1. Altered cortical processing of motor inhibition in schizophrenia.

    Science.gov (United States)

    Lindberg, Påvel G; Térémetz, Maxime; Charron, Sylvain; Kebir, Oussama; Saby, Agathe; Bendjemaa, Narjes; Lion, Stéphanie; Crépon, Benoît; Gaillard, Raphaël; Oppenheim, Catherine; Krebs, Marie-Odile; Amado, Isabelle

    2016-12-01

    Inhibition is considered a key mechanism in schizophrenia. Short-latency intracortical inhibition (SICI) in the motor cortex is reduced in schizophrenia and is considered to reflect locally deficient γ-aminobutyric acid (GABA)-ergic modulation. However, it remains unclear how SICI is modulated during motor inhibition and how it relates to neural processing in other cortical areas. Here we studied motor inhibition Stop signal task (SST) in stabilized patients with schizophrenia (N = 28), healthy siblings (N = 21) and healthy controls (n = 31) matched in general cognitive status and educational level. Transcranial magnetic stimulation (TMS) and functional magnetic resonance imaging (fMRI) were used to investigate neural correlates of motor inhibition. SST performance was similar in patients and controls. SICI was modulated by the task as expected in healthy controls and siblings but was reduced in patients with schizophrenia during inhibition despite equivalent motor inhibition performance. fMRI showed greater prefrontal and premotor activation during motor inhibition in schizophrenia. Task-related modulation of SICI was higher in subjects who showed less inhibition-related activity in pre-supplementary motor area (SMA) and cingulate motor area. An exploratory genetic analysis of selected markers of inhibition (GABRB2, GAD1, GRM1, and GRM3) did not explain task-related differences in SICI or cortical activation. In conclusion, this multimodal study provides direct evidence of a task-related deficiency in SICI modulation in schizophrenia likely reflecting deficient GABA-A related processing in motor cortex. Compensatory activation of premotor areas may explain similar motor inhibition in patients despite local deficits in intracortical processing. Task-related modulation of SICI may serve as a useful non-invasive GABAergic marker in development of therapeutic strategies in schizophrenia. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Altered velocity processing in schizophrenia during pursuit eye tracking.

    Directory of Open Access Journals (Sweden)

    Matthias Nagel

    Full Text Available Smooth pursuit eye movements (SPEM are needed to keep the retinal image of slowly moving objects within the fovea. Depending on the task, about 50%-80% of patients with schizophrenia have difficulties in maintaining SPEM. We designed a study that comprised different target velocities as well as testing for internal (extraretinal guidance of SPEM in the absence of a visual target. We applied event-related fMRI by presenting four velocities (5, 10, 15, 20°/s both with and without intervals of target blanking. 17 patients and 16 healthy participants were included. Eye movements were registered during scanning sessions. Statistical analysis included mixed ANOVAs and regression analyses of the target velocity on the Blood Oxygen Level Dependency (BOLD signal. The main effect group and the interaction of velocity×group revealed reduced activation in V5 and putamen but increased activation of cerebellar regions in patients. Regression analysis showed that activation in supplementary eye field, putamen, and cerebellum was not correlated to target velocity in patients in contrast to controls. Furthermore, activation in V5 and in intraparietal sulcus (putative LIP bilaterally was less strongly correlated to target velocity in patients than controls. Altered correlation of target velocity and neural activation in the cortical network supporting SPEM (V5, SEF, LIP, putamen implies impaired transformation of the visual motion signal into an adequate motor command in patients. Cerebellar regions seem to be involved in compensatory mechanisms although cerebellar activity in patients was not related to target velocity.

  3. Cerebral metabolic and structural alterations in hereditary spastic paraplegia with thin corpus callosum assessed by MRS and DTI

    International Nuclear Information System (INIS)

    Dreha-Kulaczewski, Steffi; Dechent, Peter; Helms, Gunther; Frahm, Jens; Gaertner, Jutta; Brockmann, Knut

    2006-01-01

    Hereditary spastic paraplegia with thin corpus callosum (HSP-TCC) is a complicated form of autosomal-recessive hereditary spastic paraplegia. Characteristic clinical features comprise progressive spastic gait, cognitive impairment, and ataxia. Diagnostic MRI findings include thinning of the corpus callosum and non-progressive white matter (WM) alterations. To study the extent of axonal involvement, we performed localized proton magnetic resonance spectroscopy (MRS) of the cerebral WM and cortical grey matter (GM) in a patient with HSP-TCC at 20 and 25 years of age. The second investigation included diffusion tensor imaging (DTI). While MRS of the GM was normal, affected WM was characterized by major metabolic alterations such as reduced concentrations of N-acetylaspartate and N-acetylaspartyl-glutamate, creatine and phosphocreatine, and choline-containing compounds as well as elevated levels of myo-inositol. These abnormalities showed progression over a period of 5 years. DTI revealed increased mean diffusivity as well as reduced fractional anisotropy in periventricular WM. The metabolic and structural findings are consistent with progressive neuroaxonal loss in the WM accompanied by astrocytic proliferation - histopathological changes known to occur in HSP-TCC. Our results are in agreement with the hypothesis that the primary pathological process in HSP-TCC affects the axon, possibly due to impaired axonal trafficking. (orig.)

  4. Integrated analysis of HPV-mediated immune alterations in cervical cancer.

    Science.gov (United States)

    Chen, Long; Luan, Shaohong; Xia, Baoguo; Liu, Yansheng; Gao, Yuan; Yu, Hongyan; Mu, Qingling; Zhang, Ping; Zhang, Weina; Zhang, Shengmiao; Wei, Guopeng; Yang, Min; Li, Ke

    2018-05-01

    Human papillomavirus (HPV) infection is the primary cause of cervical cancer. HPV-mediated immune alterations are known to play crucial roles in determining viral persistence and host cell transformation. We sought to thoroughly understand HPV-directed immune alterations in cervical cancer by exploring publically available datasets. 130 HPV positive and 7 HPV negative cervical cancer cases from The Cancer Genome Atlas were compared for differences in gene expression levels and functional enrichment. Analyses for copy number variation (CNV) and genetic mutation were conducted for differentially expressed immune genes. Kaplan-Meier analysis was performed to assess survival and relapse differences across cases with or without alterations of the identified immune signature genes. Genes up-regulated in HPV positive cervical cancer were enriched for various gene ontology terms of immune processes (P=1.05E-14~1.00E-05). Integrated analysis of the differentially expressed immune genes identified 9 genes that displayed either CNV, genetic mutation and/or gene expression changes in at least 10% of the cases of HPV positive cervical cancer. Genomic amplification may cause elevated levels of these genes in some HPV positive cases. Finally, patients with alterations in at least one of the nine signature genes overall had earlier relapse compared to those without any alterations. The altered expression of either TFRC or MMP13 may indicate poor survival for a subset of cervical cancer patients (P=1.07E-07). We identified a novel immune gene signature for HPV positive cervical cancer that is potentially associated with early relapse of cervical cancer. Copyright © 2018. Published by Elsevier Inc.

  5. Uranium occurence in nature: Geophysical prospecting, and its occurence in Syria

    International Nuclear Information System (INIS)

    Al-Haj Rasheed, Zaki

    1985-01-01

    A general idea about naturaly occured uranium minerals such as uranite, pechblende, carnotite, coffinit, and bronnerit is given. At the same time, different geophysical methods and detecting devices applied for uranium exploration have been demonstrated. Investigations and studies carried out in Syria point to a uranium content of 100 ppm in the exploited Syrian phosphorite. 1 fig., 1 tab

  6. Naturally occurring radioactive materials at New South Wales mines

    International Nuclear Information System (INIS)

    McLaughlin, Robert

    2013-01-01

    Until recently mines in New South Wales have been largely exempt from the provisions of the Radiation Control Act with respect to radioactive ore being mined and processed. Legislative changes and the national harmonisation efforts for mine safety regulation have drawn attention to the emerging issue of naturally occurring radioactive material (NORM). While mine operators are already obliged under their duty of care to manage this hazard, specific control measures are increasingly expected by the community and regulators. This applies throughout the whole mine life cycle from exploration right through to rehabilitation.

  7. Photochemical alteration of organic carbon draining permafrost soils shifts microbial metabolic pathways and stimulates respiration.

    Science.gov (United States)

    Ward, Collin P; Nalven, Sarah G; Crump, Byron C; Kling, George W; Cory, Rose M

    2017-10-03

    In sunlit waters, photochemical alteration of dissolved organic carbon (DOC) impacts the microbial respiration of DOC to CO 2 . This coupled photochemical and biological degradation of DOC is especially critical for carbon budgets in the Arctic, where thawing permafrost soils increase opportunities for DOC oxidation to CO 2 in surface waters, thereby reinforcing global warming. Here we show how and why sunlight exposure impacts microbial respiration of DOC draining permafrost soils. Sunlight significantly increases or decreases microbial respiration of DOC depending on whether photo-alteration produces or removes molecules that native microbial communities used prior to light exposure. Using high-resolution chemical and microbial approaches, we show that rates of DOC processing by microbes are likely governed by a combination of the abundance and lability of DOC exported from land to water and produced by photochemical processes, and the capacity and timescale that microbial communities have to adapt to metabolize photo-altered DOC.The role of dissolved organic carbon (DOC) photo-alteration in the microbial respiration of DOC to CO 2 is unclear. Here, the authors show that the impact of this mechanism depends on whether photo-alteration of DOC produces or removes molecules used by native microbial communities prior to light exposure.

  8. Inhibition of the alpha-ketoglutarate dehydrogenase complex alters mitochondrial function and cellular calcium regulation.

    Science.gov (United States)

    Huang, Hsueh-Meei; Zhang, Hui; Xu, Hui; Gibson, Gary E

    2003-01-20

    Mitochondrial dysfunction occurs in many neurodegenerative diseases. The alpha-ketoglutarate dehydrogenase complex (KGDHC) catalyzes a key and arguably rate-limiting step of the tricarboxylic acid cycle (TCA). A reduction in the activity of the KGDHC occurs in brains and cells of patients with many of these disorders and may underlie the abnormal mitochondrial function. Abnormalities in calcium homeostasis also occur in fibroblasts from Alzheimer's disease (AD) patients and in cells bearing mutations that lead to AD. Thus, the present studies test whether the reduction of KGDHC activity can lead to the alterations in mitochondrial function and calcium homeostasis. alpha-Keto-beta-methyl-n-valeric acid (KMV) inhibits KGDHC activity in living N2a cells in a dose- and time-dependent manner. Surprisingly, concentration of KMV that inhibit in situ KGDHC by 80% does not alter the mitochondrial membrane potential (MMP). However, similar concentrations of KMV induce the release of cytochrome c from mitochondria into the cytosol, reduce basal [Ca(2+)](i) by 23% (Pcalcium release from the endoplasmic reticulum (ER) by 46% (P<0.005). This result suggests that diminished KGDHC activities do not lead to the Ca(2+) abnormalities in fibroblasts from AD patients or cells bearing PS-1 mutations. The increased release of cytochrome c with diminished KGDHC activities will be expected to activate other pathways including cell death cascades. Reductions in this key mitochondrial enzyme will likely make the cells more vulnerable to metabolic insults that promote cell death.

  9. Environmental effects on growth phenology of co-occurring Eucalyptus species.

    Science.gov (United States)

    Rawal, Deepa S; Kasel, Sabine; Keatley, Marie R; Aponte, Cristina; Nitschke, Craig R

    2014-05-01

    Growth is one of the most important phenological cycles in a plant's life. Higher growth rates increase the competitive ability, survival and recruitment and can provide a measure of a plant's adaptive capacity to climate variability and change. This study identified the growth relationship of six Eucalyptus species to variations in temperature, soil moisture availability, photoperiod length and air humidity over 12 months. The six species represent two naturally co-occurring groups of three species each representing warm-dry and the cool-moist sclerophyll forests, respectively. Warm-dry eucalypts were found to be more tolerant of higher temperatures and lower air humidity than the cool-moist eucalypts. Within groups, species-specific responses were detected with Eucalyptus microcarpa having the widest phenological niche of the warm-dry species, exhibiting greater resistance to high temperature and lower air humidity. Temperature dependent photoperiodic responses were exhibited by all the species except Eucalyptus tricarpa and Eucalyptus sieberi, which were able to maintain growth as photoperiod shortened but temperature requirements were fulfilled. Eucalyptus obliqua exhibited a flexible growth rate and tolerance to moisture limitation which enables it to maintain its growth rate as water availability changes. The wider temperature niche exhibited by E. sieberi compared with E. obliqua and Eucalyptus radiata may improve its competitive ability over these species where winters are warm and moisture does not limit growth. With climate change expected to result in warmer and drier conditions in south-east Australia, the findings of this study suggest all cool-moist species will likely suffer negative effects on growth while the warm-dry species may still maintain current growth rates. Our findings highlight that climate driven shifts in growth phenology will likely occur as climate changes and this may facilitate changes in tree communities by altering inter

  10. Altered growth pattern, not altered growth per se, is the hallmark of early lesions preceding cancer development.

    Science.gov (United States)

    Doratiotto, S; Marongiu, F; Faedda, S; Pani, P; Laconi, E

    2009-01-01

    Many human solid cancers arise from focal proliferative lesions that long precede the overt clinical appearance of the disease. The available evidence supports the notion that cancer precursor lesions are clonal in origin, and this notion forms the basis for most of the current theories on the pathogenesis of neoplastic disease. In contrast, far less attention has been devoted to the analysis of the phenotypic property that serves to define these focal lesions, i.e. their altered growth pattern. In fact, the latter is often considered a mere morphological by-product of clonal growth, with no specific relevance in the process. In the following study, evidence will be presented to support the concept that focal growth pattern is an inherent property of altered cells, independent of clonal growth; furthermore, it will be discussed how such a property, far from being merely descriptive, might indeed play a fundamental role in the sequence of events leading to the development of cancer. Within this paradigm, the earliest steps of neoplasia should be considered and analysed as defects in the mechanisms of tissue pattern formation.

  11. A preconscious neural mechanism of hypnotically altered colors: a double case study.

    Directory of Open Access Journals (Sweden)

    Mika Koivisto

    Full Text Available Hypnotic suggestions may change the perceived color of objects. Given that chromatic stimulus information is processed rapidly and automatically by the visual system, how can hypnotic suggestions affect perceived colors in a seemingly immediate fashion? We studied the mechanisms of such color alterations by measuring electroencephalography in two highly suggestible participants as they perceived briefly presented visual shapes under posthypnotic color alternation suggestions such as "all the squares are blue". One participant consistently reported seeing the suggested colors. Her reports correlated with enhanced evoked upper beta-band activity (22 Hz 70-120 ms after stimulus in response to the shapes mentioned in the suggestion. This effect was not observed in a control condition where the participants merely tried to simulate the effects of the suggestion on behavior. The second participant neither reported color alterations nor showed the evoked beta activity, although her subjective experience and event-related potentials were changed by the suggestions. The results indicate a preconscious mechanism that first compares early visual input with a memory representation of the suggestion and consequently triggers the color alteration process in response to the objects specified by the suggestion. Conscious color experience is not purely the result of bottom-up processing but it can be modulated, at least in some individuals, by top-down factors such as hypnotic suggestions.

  12. Imaging alterations of cardiomyocyte cAMP microdomains in disease

    Directory of Open Access Journals (Sweden)

    Alexander eFroese

    2015-08-01

    Full Text Available 3’,5’-cyclic adenosine monophosphate (cAMP is an important second messenger which regulates heart function by acting in distinct subcellular microdomains. Recent years have provided deeper mechanistic insights into compartmentalized cAMP signaling and its link to cardiac disease. In this mini review, we summarize newest developments in this field achieved by cutting-edge biochemical and biophysical techniques. We further compile the data from different studies into a bigger picture of so far uncovered alterations in cardiomyocyte cAMP microdomains which occur in compensated cardiac hypertrophy and chronic heart failure. Finally, future research directions and translational perspectives are briefly discussed.

  13. Oxidation mechanisms occurring in wines

    OpenAIRE

    Oliveira, Carla Maria; Ferreira, António César Silva; Freitas, Victor De; Silva, Artur M. S.

    2011-01-01

    The present review aims to show the state of the art on the oxidation mechanisms occurring in wines, as well as the methods to monitor, classify and diagnose wine oxidation. Wine oxidation can be divided in enzymatic oxidation and non-enzymatic oxidation. Enzymatic oxidation almost entirely occurs in grape must and is largely correlated with the content of hydroxycinnamates, such as caffeoyltartaric acid and paracoumaroyltartaric acid, and flavan-3-ols. Non-enzymatic oxidation, al...

  14. Genetic alterations in head and neck squamous cell carcinomas

    Directory of Open Access Journals (Sweden)

    Nagai M.A.

    1999-01-01

    Full Text Available The genetic alterations observed in head and neck cancer are mainly due to oncogene activation (gain of function mutations and tumor suppressor gene inactivation (loss of function mutations, leading to deregulation of cell proliferation and death. These genetic alterations include gene amplification and overexpression of oncogenes such as myc, erbB-2, EGFR and cyclinD1 and mutations, deletions and hypermethylation leading to p16 and TP53 tumor suppressor gene inactivation. In addition, loss of heterozygosity in several chromosomal regions is frequently observed, suggesting that other tumor suppressor genes not yet identified could be involved in the tumorigenic process of head and neck cancers. The exact temporal sequence of the genetic alterations during head and neck squamous cell carcinoma (HNSCC development and progression has not yet been defined and their diagnostic or prognostic significance is controversial. Advances in the understanding of the molecular basis of head and neck cancer should help in the identification of new markers that could be used for the diagnosis, prognosis and treatment of the disease.

  15. [Prevalence of obesity and altered lipid profile in university students].

    Science.gov (United States)

    González Sandoval, Claudia Elena; Díaz Burke, Yolanda; Mendizabal-Ruiz, Adriana Patricia; Medina Díaz, Eunice; Morales, José Alejandro

    2014-02-01

    Obesity is a serious public health problem because its association with the risk to develop various chronic diseases. Atherogenic dyslipidemia that often accompany obesity is also associated to the metabolic syndrome and to cardiovascular diseases. The transition from adolescence to young adulthood appears to be a period where major changes occur in the lifestyle which contributes to the development of obesity, however, little attention has been given to this transition stage. The inclination to adopt unhealthy behaviors which occurs during early adulthood may be increased on university students because their lifestyle, which is characterized by lack of time to eat a healthy diet, which can make them susceptible to obesity. To determine the prevalence of obesity and lipid levels abnormalities and their relationship in a group of university students. Transversal study of university students aged between 18 and 24 years. Body mass index, waist circumference and blood lipid profile where evaluated. Of the 620 students surveyed about one-third have either overweight or obesity. 86% of students had at least one alteration in the evaluated parameters. Lipid profile results show a high prevalence of minor alterations in levels, particularly in cholesterol linked to low density lipoproteins levels. University young students have a high prevalence of overweight and plasma lipid levels above the norm, but most are in the low-risk categories. It is necessary to establish early preventive measures aimed at promoting in the university student good eating habits and increased physical activity. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

  16. A study of the alterability of terminal residues stabilized by a mineral-binder-based solidification/stabilization process; Etude de l`alterabilite de residus ultimes stabilises par un procede de solidification, stabilisation a base de liants mineraux

    Energy Technology Data Exchange (ETDEWEB)

    Humez, N.; Prost, R. [Institut National de Recherches Agronomiques (INRA), 78 - Versailles (France). Unite de Science du Sol; Piketty, L.; Schnuriger, B.; Benchara, A.; Pichat, P. [Centre de Solidification, Stabilisation et Stockage, Sarp Industries, 78 - Limay (France)

    1997-12-31

    A new laboratory approach has been developed for the study of the long term behaviour of stabilized terminal residues, and is based on the experimental method for the study of rock alteration. The method consists in examining the migration of elements that are present in the solution contained in the pores, and studying the structural modifications which result from the dissolution of certain constituents, the transformation and the neo-formation of other ones in the material. The method allows for the evaluation, in a short time, of the alterability and perenniality of stabilized terminal wastes. Results show that the long term alterability of solidified/stabilized samples that have been processed using the ECOFIX method, is low

  17. Surface alteration and physical properties of glass from the Cretaceous-Tertiary boundary

    Science.gov (United States)

    Barkatt, A.; Sang, J.C.; Thorpe, A.N.; Senftle, F.E.; Talmy, I.G.; Norr, M.K.; Mazer, J.J.; Izett, G.; Sigurdsson, Haraldur

    1994-01-01

    The scalloped surface feature on Cretaceous-Tertiary boundary glass is often explained as being due to terrestrial aqueous leaching. Leaching of man-made glass results in a reduction in density of the glass. Also, Fe, because of its relative insolubility, is concentrated by the leaching process. Thus, the Haitian glass specimens which have been heavily altered should have a thin rim of less dense glass in which the Fe is concentrated compared to the core glass. The higher Fe concentration in the rim glass should cause it to have an enhanced Curie constant and a lower density compared to the unaltered glass. The magnetic Curie constant, density, and scanning electron microscopic studies were made on altered specimens of Haitian glass and also on specimens showing a minimum of alteration. The results show that the less altered samples have the highest density and the lowest Curie constant. The data substantiate the terrestrial hypothesis. ?? 1994.

  18. A new approach for handling longitudinal count data with zero-inflation and overdispersion: poisson geometric process model.

    Science.gov (United States)

    Wan, Wai-Yin; Chan, Jennifer S K

    2009-08-01

    For time series of count data, correlated measurements, clustering as well as excessive zeros occur simultaneously in biomedical applications. Ignoring such effects might contribute to misleading treatment outcomes. A generalized mixture Poisson geometric process (GMPGP) model and a zero-altered mixture Poisson geometric process (ZMPGP) model are developed from the geometric process model, which was originally developed for modelling positive continuous data and was extended to handle count data. These models are motivated by evaluating the trend development of new tumour counts for bladder cancer patients as well as by identifying useful covariates which affect the count level. The models are implemented using Bayesian method with Markov chain Monte Carlo (MCMC) algorithms and are assessed using deviance information criterion (DIC).

  19. Altered olfactory processing of stress-related body odors and artificial odors in patients with panic disorder.

    Science.gov (United States)

    Wintermann, Gloria-Beatrice; Donix, Markus; Joraschky, Peter; Gerber, Johannes; Petrowski, Katja

    2013-01-01

    Patients with Panic Disorder (PD) direct their attention towards potential threat, followed by panic attacks, and increased sweat production. Onés own anxiety sweat odor influences the attentional focus, and discrimination of threat or non-threat. Since olfactory projection areas overlap with neuronal areas of a panic-specific fear network, the present study investigated the neuronal processing of odors in general and of stress-related sweat odors in particular in patients with PD. A sample of 13 patients with PD with/ without agoraphobia and 13 age- and gender-matched healthy controls underwent an fMRI investigation during olfactory stimulation with their stress-related sweat odors (TSST, ergometry) as well as artificial odors (peach, artificial sweat) as non-fearful non-body odors. The two groups did not differ with respect to their olfactory identification ability. Independent of the kind of odor, the patients with PD showed activations in fronto-cortical areas in contrast to the healthy controls who showed activations in olfaction-related areas such as the amygdalae and the hippocampus. For artificial odors, the patients with PD showed a decreased neuronal activation of the thalamus, the posterior cingulate cortex and the anterior cingulate cortex. Under the presentation of sweat odor caused by ergometric exercise, the patients with PD showed an increased activation in the superior temporal gyrus, the supramarginal gyrus, and the cingulate cortex which was positively correlated with the severity of the psychopathology. For the sweat odor from the anxiety condition, the patients with PD showed an increased activation in the gyrus frontalis inferior, which was positively correlated with the severity of the psychopathology. The results suggest altered neuronal processing of olfactory stimuli in PD. Both artificial odors and stress-related body odors activate specific parts of a fear-network which is associated with an increased severity of the psychopathology.

  20. Altered olfactory processing of stress-related body odors and artificial odors in patients with panic disorder.

    Directory of Open Access Journals (Sweden)

    Gloria-Beatrice Wintermann

    Full Text Available Patients with Panic Disorder (PD direct their attention towards potential threat, followed by panic attacks, and increased sweat production. Onés own anxiety sweat odor influences the attentional focus, and discrimination of threat or non-threat. Since olfactory projection areas overlap with neuronal areas of a panic-specific fear network, the present study investigated the neuronal processing of odors in general and of stress-related sweat odors in particular in patients with PD.A sample of 13 patients with PD with/ without agoraphobia and 13 age- and gender-matched healthy controls underwent an fMRI investigation during olfactory stimulation with their stress-related sweat odors (TSST, ergometry as well as artificial odors (peach, artificial sweat as non-fearful non-body odors.The two groups did not differ with respect to their olfactory identification ability. Independent of the kind of odor, the patients with PD showed activations in fronto-cortical areas in contrast to the healthy controls who showed activations in olfaction-related areas such as the amygdalae and the hippocampus. For artificial odors, the patients with PD showed a decreased neuronal activation of the thalamus, the posterior cingulate cortex and the anterior cingulate cortex. Under the presentation of sweat odor caused by ergometric exercise, the patients with PD showed an increased activation in the superior temporal gyrus, the supramarginal gyrus, and the cingulate cortex which was positively correlated with the severity of the psychopathology. For the sweat odor from the anxiety condition, the patients with PD showed an increased activation in the gyrus frontalis inferior, which was positively correlated with the severity of the psychopathology.The results suggest altered neuronal processing of olfactory stimuli in PD. Both artificial odors and stress-related body odors activate specific parts of a fear-network which is associated with an increased severity of the

  1. LSD Increases Primary Process Thinking via Serotonin 2A Receptor Activation

    Directory of Open Access Journals (Sweden)

    Rainer Kraehenmann

    2017-11-01

    Full Text Available Rationale: Stimulation of serotonin 2A (5-HT2A receptors by lysergic acid diethylamide (LSD and related compounds such as psilocybin has previously been shown to increase primary process thinking – an ontologically and evolutionary early, implicit, associative, and automatic mode of thinking which is typically occurring during altered states of consciousness such as dreaming. However, it is still largely unknown whether LSD induces primary process thinking under placebo-controlled, standardized experimental conditions and whether these effects are related to subjective experience and 5-HT2A receptor activation. Therefore, this study aimed to test the hypotheses that LSD increases primary process thinking and that primary process thinking depends on 5-HT2A receptor activation and is related to subjective drug effects.Methods: Twenty-five healthy subjects performed an audio-recorded mental imagery task 7 h after drug administration during three drug conditions: placebo, LSD (100 mcg orally and LSD together with the 5-HT2A receptor antagonist ketanserin (40 mg orally. The main outcome variable in this study was primary index (PI, a formal measure of primary process thinking in the imagery reports. State of consciousness was evaluated using the Altered State of Consciousness (5D-ASC rating scale.Results: LSD, compared with placebo, significantly increased primary index (p < 0.001, Bonferroni-corrected. The LSD-induced increase in primary index was positively correlated with LSD-induced disembodiment (p < 0.05, Bonferroni-corrected, and blissful state (p < 0.05, Bonferroni-corrected on the 5D-ASC. Both LSD-induced increases in primary index and changes in state of consciousness were fully blocked by ketanserin.Conclusion: LSD induces primary process thinking via activation of 5-HT2A receptors and in relation to disembodiment and blissful state. Primary process thinking appears to crucially organize inner experiences during both dreams and

  2. LSD Increases Primary Process Thinking via Serotonin 2A Receptor Activation

    Science.gov (United States)

    Kraehenmann, Rainer; Pokorny, Dan; Aicher, Helena; Preller, Katrin H.; Pokorny, Thomas; Bosch, Oliver G.; Seifritz, Erich; Vollenweider, Franz X.

    2017-01-01

    Rationale: Stimulation of serotonin 2A (5-HT2A) receptors by lysergic acid diethylamide (LSD) and related compounds such as psilocybin has previously been shown to increase primary process thinking – an ontologically and evolutionary early, implicit, associative, and automatic mode of thinking which is typically occurring during altered states of consciousness such as dreaming. However, it is still largely unknown whether LSD induces primary process thinking under placebo-controlled, standardized experimental conditions and whether these effects are related to subjective experience and 5-HT2A receptor activation. Therefore, this study aimed to test the hypotheses that LSD increases primary process thinking and that primary process thinking depends on 5-HT2A receptor activation and is related to subjective drug effects. Methods: Twenty-five healthy subjects performed an audio-recorded mental imagery task 7 h after drug administration during three drug conditions: placebo, LSD (100 mcg orally) and LSD together with the 5-HT2A receptor antagonist ketanserin (40 mg orally). The main outcome variable in this study was primary index (PI), a formal measure of primary process thinking in the imagery reports. State of consciousness was evaluated using the Altered State of Consciousness (5D-ASC) rating scale. Results: LSD, compared with placebo, significantly increased primary index (p LSD-induced increase in primary index was positively correlated with LSD-induced disembodiment (p LSD-induced increases in primary index and changes in state of consciousness were fully blocked by ketanserin. Conclusion: LSD induces primary process thinking via activation of 5-HT2A receptors and in relation to disembodiment and blissful state. Primary process thinking appears to crucially organize inner experiences during both dreams and psychedelic states of consciousness. PMID:29167644

  3. Alterations in the developing testis transcriptome following embryonic vinclozolin exposure.

    Science.gov (United States)

    Clement, Tracy M; Savenkova, Marina I; Settles, Matthew; Anway, Matthew D; Skinner, Michael K

    2010-11-01

    The current study investigates the direct effects of in utero vinclozolin exposure on the developing F1 generation rat testis transcriptome. Previous studies have demonstrated that exposure to vinclozolin during embryonic gonadal sex determination induces epigenetic modifications of the germ line and transgenerational adult onset disease states. Microarray analyses were performed to compare control and vinclozolin treated testis transcriptomes at embryonic days 13, 14 and 16. A total of 576 differentially expressed genes were identified and the major cellular functions and pathways associated with these altered transcripts were examined. The sets of regulated genes at the different development periods were found to be transiently altered and distinct. Categorization by major known functions of altered genes was performed. Specific cellular process and pathway analyses suggest the involvement of Wnt and calcium signaling, vascular development and epigenetic mechanisms as potential mediators of the direct F1 generation actions of vinclozolin. Copyright © 2010 Elsevier Inc. All rights reserved.

  4. Meta-analysis of diffusion tensor imaging (DTI) studies shows altered fractional anisotropy occurring in distinct brain areas in association with depression

    LENUS (Irish Health Repository)

    Murphy, Melissa L

    2011-09-27

    Abstract Fractional anisotropy anomalies occurring in the white matter tracts in the brains of depressed patients may reflect microstructural changes underlying the pathophysiology of this disorder. We conducted a meta-analysis of fractional anisotropy abnormalities occurring in major depressive disorder using voxel-based diffusion tensor imaging studies. Using the Embase, PubMed and Google Scholar databases, 89 relevant data sets were identified, of which 7 (including 188 patients with major depressive disorder and 221 healthy controls) met our inclusion criteria. Authors were contacted to retrieve any additional data required. Coordinates were extracted from clusters of significant white matter fractional anisotropy differences between patients and controls. Relevant demographic, clinical and methodological variables were extracted from each study or obtained directly from authors. The meta-analysis was carried out using Signed Differential Mapping. Patients with depression showed decreased white matter fractional anisotropy values in the superior longitudinal fasciculus and increased fractional anisotropy values in the fronto-occipital fasciculus compared to controls. Using quartile and jackknife sensitivity analysis, we found that reduced fractional anisotropy in the left superior longitudinal fasciculus was very stable, with increases in the right fronto-occipital fasciculus driven by just one study. In conclusion, our meta-analysis revealed a significant reduction in fractional anisotropy values in the left superior longitudinal fasciculus, which may ultimately play an important role in the pathology of depression.

  5. Epstein-Barr virus (EBV) LMP2A alters normal transcriptional regulation following B-cell receptor activation

    International Nuclear Information System (INIS)

    Portis, Toni; Longnecker, Richard

    2004-01-01

    The latent membrane protein 2A (LMP2A) of Epstein-Barr virus (EBV) is an important mediator of viral latency in infected B-lymphocytes. LMP2A inhibits B-cell receptor (BCR) signaling in vitro and allows for the survival of BCR-negative B cells in vivo. In this study, we compared gene transcription in BCR-activated B cells from non-transgenic and LMP2A Tg6 transgenic mice. We found that the transcriptional induction and down-regulation of many genes that normally occurs in B cells following BCR activation did not occur in B cells from LMP2A Tg6 transgenic mice. Furthermore, LMP2A induced the expression of various transcription factors and genes associated with DNA/RNA metabolism, which may allow for the altered transcriptional regulation observed in BCR-activated B cells from LMP2A Tg6 mice. These results suggest that LMP2A may inhibit the downstream effects of BCR signaling by directly or indirectly altering gene transcription to ensure EBV persistence in infected B cells

  6. Influence of microorganisms on the alteration of glasses; Influence des microorganismes sur l'alteration des verres

    Energy Technology Data Exchange (ETDEWEB)

    Besnainou, B; Libert, M F [CEA Cadarache, 13 - Saint Paul lez Durance (France). Dept. d' Entreposage et de Stockage des Dechets

    1997-07-01

    Under specific conditions, microorganisms may enhance the alteration process of basaltic glass. However bacterial activity in the near field of a glass container would be possible only in environmental conditions provide nutrients and energetic substrates for bacterial growth. Depending of these conditions, microorganisms can: - modify the pH or the medium, - consume or produce soluble organic acids. To qualify the long term behaviour of glass, in presence of microorganisms, a qualitative and quantitative estimation of microbial activity potentialities and their consequences is needed. This must be achieved in studying the availability of the chemical species in the environment. (authors)

  7. Fundamental study of hydrogen-attachment-induced peptide fragmentation occurring in the gas phase and during the matrix-assisted laser desorption/ionization process.

    Science.gov (United States)

    Asakawa, Daiki; Takahashi, Hidenori; Iwamoto, Shinichi; Tanaka, Koichi

    2018-05-09

    Mass spectrometry with hydrogen-radical-mediated fragmentation techniques has been used for the sequencing of proteins/peptides. The two methods, matrix-assisted laser desorption/ionization in-source decay (MALDI-ISD) and hydrogen attachment/abstraction dissociation (HAD) are known as hydrogen-radical-mediated fragmentation techniques. MALDI-ISD occurs during laser induced desorption processes, whereas HAD utilizes the association of hydrogen with peptide ions in the gas phase. In this study, the general mechanisms of MALDI-ISD and HAD of peptides were investigated. We demonstrated the fragmentation of four model peptides and investigated the fragment formation pathways using density functional theory (DFT) calculations. The current experimental and computational joint study indicated that MALDI-ISD and HAD produce aminoketyl radical intermediates, which immediately undergo radical-induced cleavage at the N-Cα bond located on the C-terminal side of the radical site, leading to the c'/z˙ fragment pair. In the case of MALDI-ISD, the z˙ fragments undergo a subsequent reaction with the matrix to give z' and matrix adducts of the z fragments. In contrast, the c' and z˙ fragments react with hydrogen atoms during the HAD processes, and various fragment species, such as c˙, c', z˙ and z', were observed in the HAD-MS/MS mass spectra.

  8. Holistic processing for other-race faces in chinese participants occurs for upright but not inverted faces.

    Science.gov (United States)

    Crookes, Kate; Favelle, Simone; Hayward, William G

    2013-01-01

    Recent evidence suggests stronger holistic processing for own-race faces may underlie the own-race advantage in face memory. In previous studies Caucasian participants have demonstrated larger holistic processing effects for Caucasian over Asian faces. However, Asian participants have consistently shown similar sized effects for both Asian and Caucasian faces. We investigated two proposed explanations for the holistic processing of other-race faces by Asian participants: (1) greater other-race exposure, (2) a general global processing bias. Holistic processing was tested using the part-whole task. Participants were living in predominantly own-race environments and other-race contact was evaluated. Despite reporting significantly greater contact with own-race than other-race people, Chinese participants displayed strong holistic processing for both Asian and Caucasian upright faces. In addition, Chinese participants showed no evidence of holistic processing for inverted faces arguing against a general global processing bias explanation. Caucasian participants, in line with previous studies, displayed stronger holistic processing for Caucasian than Asian upright faces. For inverted faces there were no race-of-face differences. These results are used to suggest that Asians may make more general use of face-specific mechanisms than Caucasians.

  9. Music alters visual perception.

    Directory of Open Access Journals (Sweden)

    Jacob Jolij

    Full Text Available BACKGROUND: Visual perception is not a passive process: in order to efficiently process visual input, the brain actively uses previous knowledge (e.g., memory and expectations about what the world should look like. However, perception is not only influenced by previous knowledge. Especially the perception of emotional stimuli is influenced by the emotional state of the observer. In other words, how we perceive the world does not only depend on what we know of the world, but also by how we feel. In this study, we further investigated the relation between mood and perception. METHODS AND FINDINGS: We let observers do a difficult stimulus detection task, in which they had to detect schematic happy and sad faces embedded in noise. Mood was manipulated by means of music. We found that observers were more accurate in detecting faces congruent with their mood, corroborating earlier research. However, in trials in which no actual face was presented, observers made a significant number of false alarms. The content of these false alarms, or illusory percepts, was strongly influenced by the observers' mood. CONCLUSIONS: As illusory percepts are believed to reflect the content of internal representations that are employed by the brain during top-down processing of visual input, we conclude that top-down modulation of visual processing is not purely predictive in nature: mood, in this case manipulated by music, may also directly alter the way we perceive the world.

  10. Circadian Clock Synchronization of the Cell Cycle in Zebrafish Occurs through a Gating Mechanism Rather Than a Period-phase Locking Process.

    Science.gov (United States)

    Laranjeiro, Ricardo; Tamai, T Katherine; Letton, William; Hamilton, Noémie; Whitmore, David

    2018-04-01

    Studies from a number of model systems have shown that the circadian clock controls expression of key cell cycle checkpoints, thus providing permissive or inhibitory windows in which specific cell cycle events can occur. However, a major question remains: Is the clock actually regulating the cell cycle through such a gating mechanism or, alternatively, is there a coupling process that controls the speed of cell cycle progression? Using our light-responsive zebrafish cell lines, we address this issue directly by synchronizing the cell cycle in culture simply by changing the entraining light-dark (LD) cycle in the incubator without the need for pharmacological intervention. Our results show that the cell cycle rapidly reentrains to a shifted LD cycle within 36 h, with changes in p21 expression and subsequent S phase timing occurring within the first few hours of resetting. Reentrainment of mitosis appears to lag S phase resetting by 1 circadian cycle. The range of entrainment of the zebrafish clock to differing LD cycles is large, from 16 to 32 hour periods. We exploited this feature to explore cell cycle entrainment at both the population and single cell levels. At the population level, cell cycle length is shortened or lengthened under corresponding T-cycles, suggesting that a 1:1 coupling mechanism is capable of either speeding up or slowing down the cell cycle. However, analysis at the single cell level reveals that this, in fact, is not true and that a gating mechanism is the fundamental method of timed cell cycle regulation in zebrafish. Cell cycle length at the single cell level is virtually unaltered with varying T-cycles.

  11. Investigations of alteration zones based on fluid inclusion microthermometry at Sungun porphyry copper deposit, Iran

    Directory of Open Access Journals (Sweden)

    Omid ASGHARI

    2010-06-01

    Full Text Available The Sungun porphyry copper deposit is located in East Azerbaijan, NW of Iran. The porphyries occur as stocks and dikes ranging in composition from quartz monzodiorite to quartz monzonite. Four types of hypogene alteration are developed; potassic, phyllic, propylitic and argillic. Three types of fluid inclusions are typically observed at Sungun; (1 vapor-rich, (2 liquid-rich and (3 multi-phase. Halite is the principal solid phase in the latter. The primary multiphase inclusions within the quartz crystals were chosen for micro-thermometric analyses and considered to calculate the geological pressure and hydrothermal fluid density. In potassic zone, the average of homogenization temperature is 413.6 °C while in phyllic alteration, 375.9 °C. As expected in potassic alteration, the temperature of hydrothermal solutions is higher than that in the phyllic zone. The salinity of the hydrothermal fluids has a high coherency with homogenization temperature, so the average of salinity in potassic samples is 46.3 (wt% NaCl which is higher than phyllic samples. Based on the location of potassic alteration, as expected, the lithostatic pressure is much more than the phyllic one. Finally, the average density of hydrothermal fluids in the potassically altered samples is 1.124 (gr/cm3 which is higher than the ones in phyllic zone (1.083 gr/cm3 .

  12. Temporal and spatial distribution of alteration, mineralization and fluid inclusions in the transitional high-sulfidation epithermal-porphyry copper system at Red Mountain, Arizona

    Science.gov (United States)

    Lecumberri-Sanchez, Pilar; Newton, M. Claiborne; Westman, Erik C.; Kamilli, Robert J.; Canby, Vertrees M.; Bodnar, Robert J.

    2013-01-01

    the earlier magmatic fluids or may reflect the compositional evolution of fluids that exsolved from the magma. Trails of inclusions consisting of only vapor-rich inclusions are common in the shallow parts of the system, and are associated with advanced argillic alteration, suggesting that intense boiling (“flashing”) occurred at (or below) this level. Fluid inclusion assemblages consisting of coexisting vapor-rich and halite-bearing inclusions are observed in samples extending from the surface to the upper part of the late-potassic zone, indicating that fluid immiscibility occurred within this depth interval.

  13. Mindfulness training alters emotional memory recall compared to active controls: support for an emotional information processing model of mindfulness.

    Science.gov (United States)

    Roberts-Wolfe, Douglas; Sacchet, Matthew D; Hastings, Elizabeth; Roth, Harold; Britton, Willoughby

    2012-01-01

    While mindfulness-based interventions have received widespread application in both clinical and non-clinical populations, the mechanism by which mindfulness meditation improves well-being remains elusive. One possibility is that mindfulness training alters the processing of emotional information, similar to prevailing cognitive models of depression and anxiety. The aim of this study was to investigate the effects of mindfulness training on emotional information processing (i.e., memory) biases in relation to both clinical symptomatology and well-being in comparison to active control conditions. Fifty-eight university students (28 female, age = 20.1 ± 2.7 years) participated in either a 12-week course containing a "meditation laboratory" or an active control course with similar content or experiential practice laboratory format (music). Participants completed an emotional word recall task and self-report questionnaires of well-being and clinical symptoms before and after the 12-week course. Meditators showed greater increases in positive word recall compared to controls [F(1, 56) = 6.6, p = 0.02]. The meditation group increased significantly more on measures of well-being [F(1, 56) = 6.6, p = 0.01], with a marginal decrease in depression and anxiety [F(1, 56) = 3.0, p = 0.09] compared to controls. Increased positive word recall was associated with increased psychological well-being (r = 0.31, p = 0.02) and decreased clinical symptoms (r = -0.29, p = 0.03). Mindfulness training was associated with greater improvements in processing efficiency for positively valenced stimuli than active control conditions. This change in emotional information processing was associated with improvements in psychological well-being and less depression and anxiety. These data suggest that mindfulness training may improve well-being via changes in emotional information processing. Future research with a fully randomized design will be

  14. Fish extinctions alter nutrient recycling in tropical freshwaters

    OpenAIRE

    McIntyre, Peter B.; Jones, Laura E.; Flecker, Alexander S.; Vanni, Michael J.

    2007-01-01

    There is increasing evidence that species extinctions jeopardize the functioning of ecosystems. Overfishing and other human influences are reducing the diversity and abundance of fish worldwide, but the ecosystem-level consequences of these changes have not been assessed quantitatively. Recycling of nutrients is one important ecosystem process that is directly influenced by fish. Fish species vary widely in the rates at which they excrete nitrogen and phosphorus; thus, altering fish communiti...

  15. Mechanical and physical properties of hydrothermally altered rocks, Taupo Volcanic Zone, New Zealand

    Science.gov (United States)

    Wyering, L. D.; Villeneuve, M. C.; Wallis, I. C.; Siratovich, P. A.; Kennedy, B. M.; Gravley, D. M.; Cant, J. L.

    2014-11-01

    Mechanical characterization of hydrothermally altered rocks from geothermal reservoirs will lead to an improved understanding of rock mechanics in a geothermal environment. To characterize rock properties of the selected formations, we prepared samples from intact core for non-destructive (porosity, density and ultrasonic wave velocities) and destructive laboratory testing (uniaxial compressive strength). We characterised the hydrothermal alteration assemblage using optical mineralogy and existing petrography reports and showed that lithologies had a spread of secondary mineralisation that occurred across the smectite, argillic and propylitic alteration zones. The results from the three geothermal fields show a wide variety of physical rock properties. The testing results for the non-destructive testing shows that samples that originated from the shallow and low temperature section of the geothermal field had higher porosity (15 - 56%), lower density (1222 - 2114 kg/m3) and slower ultrasonic waves (1925 - 3512 m/s (vp) and 818 - 1980 m/s (vs)), than the samples from a deeper and higher temperature section of the field (1.5 - 20%, 2072 - 2837 kg/m3, 2639 - 4593 m/s (vp) and 1476 - 2752 m/s (vs), respectively). The shallow lithologies had uniaxial compressive strengths of 2 - 75 MPa, and the deep lithologies had strengths of 16 - 211 MPa. Typically samples of the same lithologies that originate from multiple wells across a field have variable rock properties because of the different alteration zones from which each sample originates. However, in addition to the alteration zones, the primary rock properties and burial depth of the samples also have an impact on the physical and mechanical properties of the rock. Where this data spread exists, we have been able to derive trends for this specific dataset and subsequently have gained an improved understanding of how hydrothermal alteration affects physical and mechanical properties.

  16. Au-bearing magnetite mineralizaion in Kashmar (alteration, mineralization, geochemistry, geochemistry and fluid inclusions;

    Directory of Open Access Journals (Sweden)

    Alireza Almasi

    2017-02-01

    Full Text Available Introduction The study area is located in the central part of the Khaf- Kashmar- Bardaskan volcano-plotunic belt (briefly KKBB. Several IOCG deposits such as Tanourjeh Au-bearing magnetite deposit and Kuh-e-Zar Specularite-rich Au deposit have been explored in KKBB. Geology, alteration, mineralization, geochemistry and fluid inclusion results in Kashmar suggest the IOCG type Au-bearing magnetite mineralization. These IOCG deposits at KKBB form at an active continental arc related to SSZ-type Sabzevar oceanic subduction. Materials and methods Use of Landsat 7+, IRS and Aster satellites. Petrography and alteration Studies in 150 thin sections of volcanic and intrusive rocks. Sampling of ore-bearing quartz vein and mineralography. Preparation of 28 geochemistry samples by the chip composite method of ore-bearing quartz vein and analyzing them in the ACME laboratory by Aqua Regia 1DX1. Fluid inclusions studies of 14 samples of quartz and barite related to the ore minerals of ore-bearing quartz vein by THM600 stage of Linkam company. Results Magmatic events in Kashmar occur at Paleocene-Eocene and include: (1 old mafic - intermediate volcano-plutonic series; (2 felsic volcanic and granitoids; and (3 parallel swarm dykes which are youngest (Almasi et al., 2016. Geochemically, Kashmar rocks are metaluminous to highly peraluminous and Tholeitic to calc-alkaline and shoshonitic in composition (Almasi et al., 2016. The field characteristics, together with isotope and geochemical analyses show that all rock types are essentially co-magmatic and post-collisional I-type (Almasi et al., 2016. Alteration of Kashmar is described in two ways: (1 intense ellipsoidal-linear Argillic-Sillicification and low sericitic with Silica caps and with medium widespread and propylitic alterations in triple regions, next to Dorouneh fault; and (2 Medium Hematite-Carbonate-Chlorite-Silicification alterations in Kamarmard heights. In parts of near the Doruneh fault, sometimes

  17. HC-Pro silencing suppressor significantly alters the gene expression profile in tobacco leaves and flowers

    Directory of Open Access Journals (Sweden)

    Lehto Kirsi

    2011-04-01

    Full Text Available Abstract Background RNA silencing is used in plants as a major defence mechanism against invasive nucleic acids, such as viruses. Accordingly, plant viruses have evolved to produce counter defensive RNA-silencing suppressors (RSSs. These factors interfere in various ways with the RNA silencing machinery in cells, and thereby disturb the microRNA (miRNA mediated endogene regulation and induce developmental and morphological changes in plants. In this study we have explored these effects using previously characterized transgenic tobacco plants which constitutively express (under CaMV 35S promoter the helper component-proteinase (HC-Pro derived from a potyviral genome. The transcript levels of leaves and flowers of these plants were analysed using microarray techniques (Tobacco 4 × 44 k, Agilent. Results Over expression of HC-Pro RSS induced clear phenotypic changes both in growth rate and in leaf and flower morphology of the tobacco plants. The expression of 748 and 332 genes was significantly changed in the leaves and flowers, respectively, in the HC-Pro expressing transgenic plants. Interestingly, these transcriptome alterations in the HC-Pro expressing tobacco plants were similar as those previously detected in plants infected with ssRNA-viruses. Particularly, many defense-related and hormone-responsive genes (e.g. ethylene responsive transcription factor 1, ERF1 were differentially regulated in these plants. Also the expression of several stress-related genes, and genes related to cell wall modifications, protein processing, transcriptional regulation and photosynthesis were strongly altered. Moreover, genes regulating circadian cycle and flowering time were significantly altered, which may have induced a late flowering phenotype in HC-Pro expressing plants. The results also suggest that photosynthetic oxygen evolution, sugar metabolism and energy levels were significantly changed in these transgenic plants. Transcript levels of S

  18. V(D)J recombination process and the Pre-B to immature B-cells transition are altered in Fanca-/- mice.

    Science.gov (United States)

    Nguyen, Thuy Vy; Pawlikowska, Patrycja; Firlej, Virginie; Rosselli, Filippo; Aoufouchi, Saïd

    2016-11-24

    B-lymphocytes in the bone marrow (BM) must generate a functional B-cell receptor and overcome the negative selection induced by reactivity with autoantigens. Two rounds of DNA recombination are required for the production of functional immunoglobulin heavy (Ig-HCs) and light (LCs) chains necessary for the continuation of B-lymphocyte development in the BM. Both rounds depend on the joint action of recombination activating gene-1 (RAG-1) and RAG-2 endonucleases with the DNA non-homologous end-joining pathway. Loss of the FANC gene leads to the chromosome breakage and cancer predisposition syndrome Fanconi anemia. Because the FANC proteins are involved in certain aspects of the recombination process, we sought to determine the impact of the FANC pathway on the Ig diversification process using Fanca -/- mice. In this work we demonstrated that Fanca -/- animals have a mild B-cell differentiation defect characterized by a specific alteration of the IgM - to IgM + transition of the B220 low B-cell population. Pre-B cells from Fanca -/- mice show evidence of impaired kLC rearrangement at the level of the Vk-Jk junction. Furthermore, Fanca -/- mice showed a skewed Vκ gene usage during formation of the LCs Vk-Jk junctions. Therefore, the Fanca protein appears as a yet unidentified factor involved in the primary diversification of Ig.

  19. Environmental Pollution by Heavy Metals in the Soil Resources of Zakhur District, as Examined through Geological Processes

    International Nuclear Information System (INIS)

    Jalilzadeh, J.; Siahcheshm, K.

    2016-01-01

    In order to assess soil pollution formed on the alteration zones of Zakhur District, we used 20 ICP-MS analyses. Argillic, argillic-phyllic, advanced argillic, silicic along with Cu, Fe, Pb, Zn, Co, Ni, Au and Ag are the most important decentralized natural resource contaminating agents that have formed extensive heavy/toxic metal haloes in this area. Diverse environmental pollution indices (e.g. geo-accumulation-Igeo, modified contamination degree- mCd and potential ecological risk- RI) show that the leve of environmental pollution risk of Pb is considerable and, as in different alteration zones, quaternary sediments are also very high. Soils highly contaminated with sulfur result in the high sulfide mineralization character of the alteration zones in Zakhur District. Calculations of the mass changes in argillic and silisic zones indicate enrichment by Cr, Ni, As, Pb and S and loss of Hg and Cd. Besides the positive correlation of heavy metals with each other, there are significant correlations between them and Mn and Al which may have occurred due to the adsorption processes by manganese, iron oxides and/or clay minerals.

  20. Altered composition of bone as triggered by irradiation facilitates the rapid erosion of the matrix by both cellular and physicochemical processes.

    Directory of Open Access Journals (Sweden)

    Danielle E Green

    Full Text Available Radiation rapidly undermines trabecular architecture, a destructive process which proceeds despite a devastated cell population. In addition to the 'biologically orchestrated' resorption of the matrix by osteoclasts, physicochemical processes enabled by a damaged matrix may contribute to the rapid erosion of bone quality. 8w male C57BL/6 mice exposed to 5 Gy of Cs(137 γ-irradiation were compared to age-matched control at 2d, 10d, or 8w following exposure. By 10d, irradiation had led to significant loss of trabecular bone volume fraction. Assessed by reflection-based Fourier transform infrared imaging (FTIRI, chemical composition of the irradiated matrix indicated that mineralization had diminished at 2d by -4.3±4.8%, and at 10d by -5.8±3.2%. These data suggest that irradiation facilitates the dissolution of the matrix through a change in the material itself, a conclusion supported by a 13.7±4.5% increase in the elastic modulus as measured by nanoindentation. The decline in viable cells within the marrow of irradiated mice at 2d implies that the immediate collapse of bone quality and inherent increased risk of fracture is not solely a result of an overly-active biologic process, but one fostered by alterations in the material matrix that predisposes the material to erosion.

  1. Geochemical modelling of the weathering zone of the 'Mina Fe' U deposit (Spain): A natural analogue for nuclear spent fuel alteration and stability processes in radwaste disposal

    Energy Technology Data Exchange (ETDEWEB)

    Arcos, D. [AMPHOS XXI Consulting S.L., Passeig de Rubi, 29-31, 08197 Valldoreix, Barcelona (Spain)], E-mail: david.arcos@amphos21.com; Perez del Villar, L. [CIEMAT, Dpto.de Medio Ambiente, Avda, Complutense 22, 28040 Madrid (Spain); Bruno, J.; Domenech, C. [AMPHOS XXI Consulting S.L., Passeig de Rubi, 29-31, 08197 Valldoreix, Barcelona (Spain)

    2008-04-15

    The 'Mina Fe' U deposit (Salamanca, Spain) has been studied in the context of Enresa's programme for U-mine sites restoration and also as a natural analogue for processes in high-level nuclear waste (HLNW) geological disposal. The investigations encompassed an array of geoscience disciplines, such as structural geology, mineralogy, hydrogeology and elemental and isotopic geochemistry and hydrogeochemistry of the site. Based on the obtained results, a conceptual mineralogical and geochemical model was performed integrating the main geochemical processes occurring at the site: the interaction between oxidised and slightly acidic water with pyrite, pitchblende, calcite and dolomite, as essential minerals of the U fracture-filling mineralisation, and hydroxyapatite from the host rock, as the main source of P. This conceptual model has been tested in a systematic numerical model, which includes the main kinetic (pyrite and pitchblende dissolution) and equilibrium processes (carbonate mineral dissolution, and goethite, schoepite and autunite secondary precipitation). The results obtained from the reactive-transport model satisfactorily agree with the conceptual model previously established. The assumption of the precipitation of coffinite as a secondary mineral in the system cannot be correctly evaluated due to the lack of hydrochemical data from the reducing zone of the site and valid thermodynamic and kinetic data for this hydrated U(IV)-silicate. This precipitation can also be hampered by the probable existence of dissolved U(IV)-organic matter and/or uranyl carbonate complexes, which are thermodynamically stable under the alkaline and reducing conditions that prevail in the reducing zone of the system. Finally, the intense downwards oxic and acidic alteration in the upper part of the system is of no relevance for the performance assessment of a HLNW disposal. However, the acidic and oxidised conditions are quickly buffered to neutral-alkaline and

  2. Fear and Reward Circuit Alterations in Pediatric CRPS.

    Science.gov (United States)

    Simons, Laura E; Erpelding, Nathalie; Hernandez, Jessica M; Serrano, Paul; Zhang, Kunyu; Lebel, Alyssa A; Sethna, Navil F; Berde, Charles B; Prabhu, Sanjay P; Becerra, Lino; Borsook, David

    2015-01-01

    In chronic pain, a number of brain regions involved in emotion (e.g., amygdala, hippocampus, nucleus accumbens, insula, anterior cingulate, and prefrontal cortex) show significant functional and morphometric changes. One phenotypic manifestation of these changes is pain-related fear (PRF). PRF is associated with profoundly altered behavioral adaptations to chronic pain. For example, patients with a neuropathic pain condition known as complex regional pain syndrome (CRPS) often avoid use of and may even neglect the affected body area(s), thus maintaining and likely enhancing PRF. These changes form part of an overall maladaptation to chronic pain. To examine fear-related brain circuit alterations in humans, 20 pediatric patients with CRPS and 20 sex- and age-matched healthy controls underwent functional magnetic resonance imaging (fMRI) in response to a well-established fearful faces paradigm. Despite no significant differences on self-reported emotional valence and arousal between the two groups, CRPS patients displayed a diminished response to fearful faces in regions associated with emotional processing compared to healthy controls. Additionally, increased PRF levels were associated with decreased activity in a number of brain regions including the right amygdala, insula, putamen, and caudate. Blunted activation in patients suggests that (a) individuals with chronic pain may have deficits in cognitive-affective brain circuits that may represent an underlying vulnerability or consequence to the chronic pain state; and (b) fear of pain may contribute and/or maintain these brain alterations. Our results shed new light on altered affective circuits in patients with chronic pain and identify PRF as a potentially important treatment target.

  3. Modelling of Pb release during Portland cement alteration

    Energy Technology Data Exchange (ETDEWEB)

    Benard, A. [INERIS Mediterrannee, F-13545 Aix En Provence 04 (France); Rose, J.; Borschneck, D.; Bottero, J.Y. [Univ Paul Cezanne, CNRS, UMR 6635, CEREGE, IFR PMSE 112, F-13545 Aix En Provence, (France); Hazemann, J.L. [CNRS, Cristallog Lab, F-38042 Grenoble 09 (France); Proux, O. [Univ Grenoble 1, CNRS, UMR, LGIT, F-38400 St Martin Dheres (France); Trotignon, L. [CEA Cadarache, DTN, SMTM, Lab Modelisat Transferts Environm, 13 - Saint Paul lez Durance (France); Nonat, A. [Univ Bourgogne, CNRS, UMR 5613, Fac Sci Mirande, Lab Rech Reactivite Solides, F-21078 Dijon (France); Chateau, L. [ADEME, F-49004 Angers (France)

    2009-07-01

    Complex cementitious matrices undergo weathering with environmental exchange and can release metallic pollutants during alteration. The molecular mechanisms responsible for metal release are difficult to identify, though this is necessary if such processes are to be controlled. The present study determines and models the molecular mechanisms of Pb release during Portland cement leaching. As Pb release is strongly related to its speciation (i.e. atomic environment and the nature of bearing phases), the first objective of the present study was to investigate the evolution of Pb retention sites together with the evolution of the cement mineralogy during leaching. Complementary and efficient investigation tools were used, namely X-ray diffraction, micro-X-ray fluorescence and X-ray absorption fine structures. The second objective was to reproduce our results with a reactive transport code (CHESS/HYTEC) in order to test the proposed speciation model of Pb. Combined results indicate that in both the unaltered core and the altered layer of the leached cement, Pb(II) would be retained through C-S-H 'nano-structure', probably linked to a Q(1) or Q(2P) silicate tetrahedra. Moreover in the altered layer, the presence of Fe atoms in the atomic environment of Pb is highly probable. Unfortunately little is known about Fe phases in cement, which makes the interpretation difficult. Can Fe-substituted hydrogranet (C(3)AH(6)) be responsible for Pb retention? Modelling results were consistent with Pb retention through C-S-H in layers and also in an additional, possibly Fe-containing, Pb-retention phase in the altered layer. (authors)

  4. Emissions of naturally occurring radioactivity from aluminum and copper facilities. Report No. 6 (final)

    International Nuclear Information System (INIS)

    Andrews, V.E.

    1982-11-01

    This report summarizes five surveys which were conducted at a Bauxite mining operation, an alumina reduction plant, an aluminum reduction plant, an underground copper mine and mill, and an open pit copper mine and concentrator. Process components and controlled source releases were sampled for naturally occurring radioactivity. Particular emphasis was given to radon-222, lead-210, and polonium-210 emissions from crushing and drying processes

  5. 4D Flow Analysis of BAV-Related Fluid-Dynamic Alterations: Evidences of Wall Shear Stress Alterations in Absence of Clinically-Relevant Aortic Anatomical Remodeling

    Directory of Open Access Journals (Sweden)

    Filippo Piatti

    2017-06-01

    Full Text Available Bicuspid aortic valve (BAV is the most common congenital cardiac disease and is a foremost risk factor for aortopathies. Despite the genetic basis of BAV and of the associated aortopathies, BAV-related alterations in aortic fluid-dynamics, and particularly in wall shear stresses (WSSs, likely play a role in the progression of aortopathy, and may contribute to its pathogenesis. To test whether WSS may trigger aortopathy, in this study we used 4D Flow sequences of phase-contrast cardiac magnetic resonance imaging (CMR to quantitatively compare the in vivo fluid dynamics in the thoracic aorta of two groups of subjects: (i five prospectively enrolled young patients with normo-functional BAV and with no aortic dilation and (ii ten age-matched healthy volunteers. Through the semi-automated processing of 4D Flow data, the aortic bulk flow at peak systole was quantified, and WSSs acting on the endothelium of the ascending aorta were characterized throughout the systolic phase in terms of magnitude and time-dependency through a method recently developed by our group. Variables computed for each BAV patient were compared vs. the corresponding distribution of values obtained for healthy controls. In BAV patients, ascending aorta diameter was measured on cine-CMR images at baseline and at 3-year follow-up. As compared to controls, normo-functional BAV patients were characterized by minor bulk flow disturbances at peak systole. However, they were characterized by evident alterations of WSS distribution and peak values in the ascending aorta. In particular, in four BAV patients, who were characterized by right-left leaflet fusion, WSS peak values exceeded by 27–46% the 90th percentile of the distribution obtained for healthy volunteers. Only in the BAV patient with right-non-coronary leaflet fusion the same threshold was exceeded by 132%. Also, evident alterations in the time-dependency of WSS magnitude and direction were observed. Despite, these fluid

  6. Hydrothermal alteration and permeability changes in granitic intrusions related to Sn-W deposits : case study of Panasqueira (Portugal)

    Science.gov (United States)

    Launay, Gaetan; Sizaret, Stanislas; Guillou-Frottier, Laurent; Gloaguen, Eric; Melleton, Jérémie; Pichavant, Michel; Champallier, Rémi; Pinto, Filipe

    2017-04-01

    The Panasqueira Sn-W deposit occurs as a dense network of flat wolframite and cassiterite-bearing quartz veins concentrated in the vicinity of a hidden greisen cupola, and to a lesser extent as disseminated cassiterites in the greisen. Previous studies (Thadeu 1951; 1979) have suggested that the Panasqueira deposit is genetically related to magmatic activity for which the most part is unexposed, and being only represented by the greisen cupola. Hydrothermal fluid circulation during the final stages of granite crystallisation has probably led to the greisenisation of the cupola followed by the deposition of the mineralization in the veins system. Mineral replacement reactions that occurred during the greisenisation could affect rock properties (porosity, density and permeability) which control fluid circulation in the granite. This study aims to investigate effects of greisenisation reactions on the dynamic (time varying) permeability that ultimately leads to fluid circulation in the greisen cupola. To do so, petrological study and experimental determinations of hydrodynamic features (porosity and permeability) for different granite alteration levels and petrographic types (unaltered granite to greisen) are combined and then integrated in coupled numerical models of fluid circulation around the granitic intrusion. Greisen occurs in the apical part of the granitic body and results in the pervasive alteration of the granite along the granite-schist contact. This greisen consists mainly of quartz and muscovite formed by the replacement of feldspars and bleaching of biotites of the initial granite. Otherwise, greisen is generally vuggy which suggests a porosity increase of the granite during hydrothermal alteration processes. This porosity increase has a positive effect on the permeability of the granitic system. Indeed, experimental measurements of permeability with the Paterson press indicate that the initial granite is impermeable (10-20 m2) whereas the greisen is

  7. Isotopic and Chemical Evidence for Primitive Aqueous Alteration in the Tagish Lake Meteorite

    Science.gov (United States)

    Sakuma, Keisuke; Hidaka, Hiroshi; Yoneda, Shigekazu

    2018-01-01

    Aqueous alteration is one of the primitive activities that occurred on meteorite parent bodies in the early solar system. The Tagish Lake meteorite is known to show an intense parent body aqueous alteration signature. In this study, quantitative analyses of the alkaline elements and isotopic analyses of Sr and Ba from acid leachates of TL (C2-ungrouped) were performed to investigate effects of aqueous alteration. The main purpose of this study is to search for isotopic evidence of extinct 135Cs from the Ba isotopic analyses in the chemical separates from the Tagish Lake meteorite. Barium isotopic data from the leachates show variable 135Ba isotopic anomalies (ε = ‑2.6 ∼ +3.6) which correlatewith 137Ba and 138Ba suggesting a heterogeneous distribution of s- and r-rich nucleosynthetic components in the early solar system. The 87Rb–87Sr and 135Cs–135Ba decay systems on TL in this study do not provide any chronological information. The disturbance of the TL chronometers is likely a reflection of the selective dissolution of Cs and Rb given the relatively higher mobility of Cs and Rb compared to Ba and Sr, respectively, during fluid mineral interactions.

  8. Altered Ca2+ homeostasis induces Calpain-Cathepsin axis activation in sporadic Creutzfeldt-Jakob disease.

    Science.gov (United States)

    Llorens, Franc; Thüne, Katrin; Sikorska, Beata; Schmitz, Matthias; Tahir, Waqas; Fernández-Borges, Natalia; Cramm, Maria; Gotzmann, Nadine; Carmona, Margarita; Streichenberger, Nathalie; Michel, Uwe; Zafar, Saima; Schuetz, Anna-Lena; Rajput, Ashish; Andréoletti, Olivier; Bonn, Stefan; Fischer, Andre; Liberski, Pawel P; Torres, Juan Maria; Ferrer, Isidre; Zerr, Inga

    2017-04-27

    Sporadic Creutzfeldt-Jakob disease (sCJD) is the most prevalent form of human prion disease and it is characterized by the presence of neuronal loss, spongiform degeneration, chronic inflammation and the accumulation of misfolded and pathogenic prion protein (PrP Sc ). The molecular mechanisms underlying these alterations are largely unknown, but the presence of intracellular neuronal calcium (Ca 2+ ) overload, a general feature in models of prion diseases, is suggested to play a key role in prion pathogenesis.Here we describe the presence of massive regulation of Ca 2+ responsive genes in sCJD brain tissue, accompanied by two Ca 2+ -dependent processes: endoplasmic reticulum stress and the activation of the cysteine proteases Calpains 1/2. Pathogenic Calpain proteins activation in sCJD is linked to the cleavage of their cellular substrates, impaired autophagy and lysosomal damage, which is partially reversed by Calpain inhibition in a cellular prion model. Additionally, Calpain 1 treatment enhances seeding activity of PrP Sc in a prion conversion assay. Neuronal lysosomal impairment caused by Calpain over activation leads to the release of the lysosomal protease Cathepsin S that in sCJD mainly localises in axons, although massive Cathepsin S overexpression is detected in microglial cells. Alterations in Ca 2+ homeostasis and activation of Calpain-Cathepsin axis already occur at pre-clinical stages of the disease as detected in a humanized sCJD mouse model.Altogether our work indicates that unbalanced Calpain-Cathepsin activation is a relevant contributor to the pathogenesis of sCJD at multiple molecular levels and a potential target for therapeutic intervention.

  9. Out of time? - Music, consciousness states and neuropharmacological mechanisms of an altered temporality

    OpenAIRE

    Fachner, Jörg

    2009-01-01

    Drug-induced altered temporality is a well-known effect of cannabis action that is utilised from musicians and music listeners for music appreciation since the early days of jazz. Cannabis has an influence on timing processes at short time scales of hundreds of milliseconds as O’Leary et al (2003) have shown in their tapping studies, proving evidence of an altered cerebellar functioning. This paper will focus on cannabis and its action on timing and aims to discuss selected scientific streams...

  10. On the mechanical friction losses occurring in automotive differential gearboxes.

    Science.gov (United States)

    Antoni, Grégory

    2014-01-01

    In the automobile industry, the mechanical losses resulting from friction are largely responsible for various kinds of surface damage, such as the scuffing occurring in some mechanical assemblies. These scuffing processes seem to be due to a local loss of lubrication between certain mechanical elements of the same assembly, leading to a sharp increase in the friction, which can lead to a surface and volume damage in some of them, and even can cause, in the worst case, the whole destruction of the mechanical system if it has continued to operate. Predicting and checking the occurrence of this kind of undesirable phenomena, especially in some principal systems of the vehicle, represents nowadays, a crucial challenge in terms of automobile reliability and safety. This study focuses on the mechanical friction losses liable to occur in differential automobile gearboxes, which can lead in the long term to the scuffing of these mechanical systems. The friction losses involved were modeled, using a simple analytical approach, which is presented and discussed.

  11. Alterations of proteins in murine splenic cells after low dose radiation

    International Nuclear Information System (INIS)

    Chen Shali; Meng Qingyong; Liu Shuzheng

    1997-01-01

    Alterations of proteins in the nuclear and cytoplasmic fractions of splenocytes were investigated in mice 4 hours after whole body irradiation with 75 mGy X-rays by 2D-electrophoresis. It was found that alterations of 6 proteins ranging in size from 12 to 43 kD with their pI distribution from 5.6 to 6.6 were displayed in the nuclear fraction of splenocytes in irradiated mice, of which there were 4 novel proteins and 2 up-regulated proteins and at the same time alterations of 10 proteins ranging in size from 10 to 69 kD with their pI distribution from 5.3 to 8.2 were displayed in the cytoplasmic fraction of splenocytes in irradiated mice, of which there were 6 novel proteins, 1 up-regulated proteins and 3 down-regulated proteins, and 3 proteins ranging in size from 24 to 32 kD with their pI distribution from 5.2 to 6.5 disappeared after radiation. It was shown that a 32000/5.2 (MW/pI) protein molecule in the sham-irradiated cytosol of splenocytes appeared in the nuclei after radiation and a 43000/6.3 protein molecule in the sham-irradiated cytosol decreased and appeared in the nuclei after radiation. The results suggest that exchanges of protein molecules occurred between nuclear and cytoplasmic compartments after radiation

  12. Hydrothermal alteration in the Aluto-Langano geothermal field, Ethopia

    Energy Technology Data Exchange (ETDEWEB)

    Teklemariam, M. [Ethiopian Institute of Geological Surveys, Addis Adaba (Ethiopia). Geothermal Exploration Project; Battaglia, S.; Gianelli, G.; Ruggieri, G. [Consiglio Nazionale delle Ricerche, Pisa (Italy). Ist. Internazionale per le Ricerche Geotermiche

    1996-12-01

    The hydrothermal mineral assemblages found in eight wells (with a depth range of 1320-2500 m) of the active geothermal field of Aluto-Langano (Ethiopia) indicate a complex evolution of water-rock interaction processes. The zone of upflow is characterized by high temperatures (up to 335{sup o}C) and the presence of a propylitic alteration (epidote, calcite, quartz and chlorite, as major phases) coexisting with calcite and clay minerals. The zone of lateral outflow is characterized by mixing of deep and shallow waters and the occurrence of a calcite-clay alteration that overprints a previous propylitic assemblage. Clay minerals have a mushroom-shaped zonal distribution consistent with the present thermal structure of the field. Microprobe analyses have been carried out on chlorite and illite in order to apply several geothermometers. (author)

  13. Alterations in CD200-CD200R1 System during EAE Already Manifest at Presymptomatic Stages

    Directory of Open Access Journals (Sweden)

    Tony Valente

    2017-05-01

    Full Text Available In the brain of patients with multiple sclerosis, activated microglia/macrophages appear in active lesions and in normal appearing white matter. However, whether they play a beneficial or a detrimental role in the development of the pathology remains a controversial issue. The production of pro-inflammatory molecules by chronically activated microglial cells is suggested to contribute to the progression of neurodegenerative processes in neurological disease. In the healthy brain, neurons control glial activation through several inhibitory mechanisms, such as the CD200-CD200R1 interaction. Therefore, we studied whether alterations in the CD200-CD200R1 system might underlie the neuroinflammation in an experimental autoimmune encephalomyelitis (EAE model of multiple sclerosis. We determined the time course of CD200 and CD200R1 expression in the brain and spinal cord of an EAE mouse model from presymptomatic to late symptomatic stages. We also assessed the correlation with associated glial activation, inflammatory response and EAE severity. Alterations in CD200 and CD200R1 expression were mainly observed in spinal cord regions in the EAE model, mostly a decrease in CD200 and an increase in CD200R1 expression. A decrease in the expression of the mRNA encoding a full CD200 protein was detected before the onset of clinical signs, and remained thereafter. A decrease in CD200 protein expression was observed from the onset of clinical signs. By contrast, CD200R1 expression increased at EAE onset, when a glial reaction associated with the production of pro- and anti-inflammatory markers occurred, and continued to be elevated during the pathology. Moreover, the magnitude of the alterations correlated with severity of the EAE mainly in spinal cord. These results suggest that neuronal-microglial communication through CD200-CD200R1 interaction is compromised in EAE. The early decreases in CD200 expression in EAE suggest that this downregulation might also

  14. Sleep Deprivation Alters Rat Ventral Prostate Morphology, Leading to Glandular Atrophy: A Microscopic Study Contrasted with the Hormonal Assays

    Directory of Open Access Journals (Sweden)

    Daniel P. Venâncio

    2012-01-01

    Full Text Available We investigated the effect of 96 h paradoxical sleep deprivation (PSD and 21-day sleep restriction (SR on prostate morphology using stereological assays in male rats. After euthanasia, the rat ventral prostate was removed, weighed, and prepared for conventional light microscopy. Microscopic analysis of the prostate reveals that morphology of this gland was altered after 96 h of PSD and 21 days of SR, with the most important alterations occurring in the epithelium and stroma in the course of both procedures compared with the control group. Both 96 h PSD and 21-day SR rats showed lower serum testosterone and higher corticosterone levels than control rats. The significance of our result referring to the sleep deprivation was responsible for deep morphological alterations in ventral prostate tissue, like to castration microscopic modifications. This result is due to the marked alterations in hormonal status caused by PSD and SR.

  15. Sleep Deprivation Alters Rat Ventral Prostate Morphology, Leading to Glandular Atrophy: A Microscopic Study Contrasted with the Hormonal Assays

    Science.gov (United States)

    Venâncio, Daniel P.; Andersen, Monica L.; Vilamaior, Patricia S. L.; Santos, Fernanda C.; Zager, Adriano; Tufik, Sérgio; Taboga, Sebastião R.; De Mello, Marco T.

    2012-01-01

    We investigated the effect of 96 h paradoxical sleep deprivation (PSD) and 21-day sleep restriction (SR) on prostate morphology using stereological assays in male rats. After euthanasia, the rat ventral prostate was removed, weighed, and prepared for conventional light microscopy. Microscopic analysis of the prostate reveals that morphology of this gland was altered after 96 h of PSD and 21 days of SR, with the most important alterations occurring in the epithelium and stroma in the course of both procedures compared with the control group. Both 96 h PSD and 21-day SR rats showed lower serum testosterone and higher corticosterone levels than control rats. The significance of our result referring to the sleep deprivation was responsible for deep morphological alterations in ventral prostate tissue, like to castration microscopic modifications. This result is due to the marked alterations in hormonal status caused by PSD and SR. PMID:22927719

  16. Surgical Consultation as Social Process: Implications for Shared Decision Making.

    Science.gov (United States)

    Clapp, Justin T; Arriaga, Alexander F; Murthy, Sushila; Raper, Steven E; Schwartz, J Sanford; Barg, Frances K; Fleisher, Lee A

    2017-12-12

    This qualitative study examines surgical consultation as a social process and assesses its alignment with assumptions of the shared decision-making (SDM) model. SDM stresses the importance of patient preferences and rigorous discussion of therapeutic risks/benefits based on these preferences. However, empirical studies have highlighted discrepancies between SDM and realities of surgical decision making. Qualitative research can inform understanding of the decision-making process and allow for granular assessment of the nature and causes of these discrepancies. We observed consultations between 3 general surgeons and 45 patients considering undergoing 1 of 2 preference-sensitive elective operations: (1) hernia repair, or (2) cholecystectomy. These patients and surgeons also participated in semi-structured interviews. By the time of the consultation, patients and surgeons were predisposed toward certain decisions by preceding events occurring elsewhere. During the visit, surgeons had differential ability to arbitrate surgical intervention and construct the severity of patients' conditions. These upstream dynamics frequently displaced the centrality of the risk/benefit-based consent discussion. The influence of events preceding consultation suggests that decision-making models should account for broader spatiotemporal spans. Given surgeons' authority to define patients' conditions and control service provision, SDM may be premised on an overestimation of patients' power to alter the course of decision making once in a specialist's office. Considering the subordinate role of the risk/benefit discussion in many surgical decisions, it will be important to study if and how the social process of decision making is altered by SDM-oriented decision aids that foreground this discussion.

  17. Chemical and Mineralogical Features of Smectite from the Morron de Mateo Bentonite Deposit (Cabo de Gata, Almeria) in Relation to the Parent Rocks and the Alteration Processes Occurred After the Bentonite Formation: Analogies and Implications for the Engineered Clayey Barrier of a Deep Geological Rad waste Repository; Naturaleza de las Esmectitas del Yacimiento de Morron de Mateo (Cabo de Gata, Almeria) en Relacion con la Roca Madre y con los Procesos Posteriores a la Bentonitizacion: Implicaciones Analogicas para la Barrera de Ingenieria de un Almacenamiento Geologico de Residuos Radiactivos

    Energy Technology Data Exchange (ETDEWEB)

    Pelayo, M; Labajo, M A; Garcia Romero, L; Perez del Villar, L

    2009-10-12

    The Morron de Mateo bentonite deposit is being studied as a natural analogue of the thermal and geochemical effects on the clayey barrier of a Deep Geological Rad waste Repository (DGRR) after its closure, in relation to the radioactive decay of the fission products and the container corrosion. This bentonite deposit and their host rocks were intruded by a rhyodacitic volcanic dome that induced a hydrothermal metasomatic process affecting the bioclastic calcarenite beds close to the dome. Bentonite from the NE sector of the deposit have been chemically and mineralogically characterized. Pyroclastic rocks (white tuffs), epyclastic rocks (mass flow) and andesitic breccia all of them hydrothermally altered, have been studied at the site. Samples are composed of feldspars, quartz and amphybols, as inherited minerals, and phyllosilicates, zeolites, crystoballite and calcite, as new formed minerals. White tuffs have the highest phyllosilicate contents, mainly dioctahedral smectite of montmorillonite type. Epyclastic rocks and andesitic breccia have a highest proportion of inherited minerals, the new formed phillosilicates being di octahedral smectite of beidellite type and an ordered interlayer chlorite/smectite mineral, of corrensite type. Smectite from the epyclastic rocks have higher Fe and Mg contents and chemical variability, as a consequence of nature of their parent rocks. The presence of corrensite in the epyclastic rocks suggests that in the Morron de Mateo area a propilitic alteration process occurred after bentonite formation, which transformed Fe-Mg-rich smectite into corrensite. This transformation was probably favoured by the sub volcanic intrusion, which also produced a temperature increase in the geological media and a supply of Fe-Mg-rich solutions, which also were the responsible for the metasomatic transformations observed in the calcarenite beds. (Author) 57 refs.

  18. Phosphorylation states of cell cycle and DNA repair proteins can be altered by the nsSNPs

    International Nuclear Information System (INIS)

    Savas, Sevtap; Ozcelik, Hilmi

    2005-01-01

    Phosphorylation is a reversible post-translational modification that affects the intrinsic properties of proteins, such as structure and function. Non-synonymous single nucleotide polymorphisms (nsSNPs) result in the substitution of the encoded amino acids and thus are likely to alter the phosphorylation motifs in the proteins. In this study, we used the web-based NetPhos tool to predict candidate nsSNPs that either introduce or remove putative phosphorylation sites in proteins that act in DNA repair and cell cycle pathways. Our results demonstrated that a total of 15 nsSNPs (16.9%) were likely to alter the putative phosphorylation patterns of 14 proteins. Three of these SNPs (CDKN1A-S31R, OGG1-S326C, and XRCC3-T241M) have already found to be associated with altered cancer risk. We believe that this set of nsSNPs constitutes an excellent resource for further molecular and genetic analyses. The novel systematic approach used in this study will accelerate the understanding of how naturally occurring human SNPs may alter protein function through the modification of phosphorylation mechanisms and contribute to disease susceptibility

  19. Immunosenescence Is Associated With Altered Gene Expression And Epigenetic Regulation In Primary And Secondary Immune Organs

    Directory of Open Access Journals (Sweden)

    Corinne eSidler

    2013-10-01

    Full Text Available Deterioration of the immune system (immunosenescence with age is associated with an increased susceptibility to infection, autoimmune disease and cancer, and reduced responsiveness to vaccination. Immunosenescence entails a reduced supply of naïve T cells from the thymus and increased specialization of peripheral T cell clones. Both thymic involution and peripheral T cell homeostasis are thought to involve cellular senescence. In order to analyze this at the molecular level, we studied gene expression profiles, epigenetic status and genome stability in the thymus and spleen of 1-month, 4-month and 18-month-old Long Evans rats. In the thymus, altered gene expression, DNA and histone hypomethylation, increased genome instability and apoptosis were observed in 18-month-old animals compared to 1- and 4-month-old animals. In the spleen, alterations in gene expression and epigenetic regulation occurred already by the age of 4 months compared to 1 month and persisted in 18-month-old compared to 1-month-old rats. In both organs, these changes were accompanied by the altered composition of resident T cell populations. Our study suggests that both senescence and apoptosis may be involved in altered organ function.

  20. Permafrost collapse alters soil carbon stocks, respiration, CH4 , and N2O in upland tundra.

    Science.gov (United States)

    Abbott, Benjamin W; Jones, Jeremy B

    2015-12-01

    Release of greenhouse gases from thawing permafrost is potentially the largest terrestrial feedback to climate change and one of the most likely to occur; however, estimates of its strength vary by a factor of thirty. Some of this uncertainty stems from abrupt thaw processes known as thermokarst (permafrost collapse due to ground ice melt), which alter controls on carbon and nitrogen cycling and expose organic matter from meters below the surface. Thermokarst may affect 20-50% of tundra uplands by the end of the century; however, little is known about the effect of different thermokarst morphologies on carbon and nitrogen release. We measured soil organic matter displacement, ecosystem respiration, and soil gas concentrations at 26 upland thermokarst features on the North Slope of Alaska. Features included the three most common upland thermokarst morphologies: active-layer detachment slides, thermo-erosion gullies, and retrogressive thaw slumps. We found that thermokarst morphology interacted with landscape parameters to determine both the initial displacement of organic matter and subsequent carbon and nitrogen cycling. The large proportion of ecosystem carbon exported off-site by slumps and slides resulted in decreased ecosystem respiration postfailure, while gullies removed a smaller portion of ecosystem carbon but strongly increased respiration and N2 O concentration. Elevated N2 O in gully soils persisted through most of the growing season, indicating sustained nitrification and denitrification in disturbed soils, representing a potential noncarbon permafrost climate feedback. While upland thermokarst formation did not substantially alter redox conditions within features, it redistributed organic matter into both oxic and anoxic environments. Across morphologies, residual organic matter cover, and predisturbance respiration explained 83% of the variation in respiration response. Consistent differences between upland thermokarst types may contribute to the

  1. Organophosphate-Related Alterations in Myelin and Axonal Transport in the Living Mammalian Brain

    Science.gov (United States)

    2014-10-01

    stress, impairments of mitochondrial function, neuroinflammation, altered neurotrophin responses, etc. (reviewed, Soltaninejad and Abdollahi, 2009...Exposure to Chlorpyrifos in Rats: Protracted Effects on Axonal Transport, Neurotrophin Receptors, Cholinergic Markers, and Information Processing

  2. Identification of the Consistently Altered Metabolic Targets in Human Hepatocellular Carcinoma.

    Science.gov (United States)

    Nwosu, Zeribe Chike; Megger, Dominik Andre; Hammad, Seddik; Sitek, Barbara; Roessler, Stephanie; Ebert, Matthias Philip; Meyer, Christoph; Dooley, Steven

    2017-09-01

    Cancer cells rely on metabolic alterations to enhance proliferation and survival. Metabolic gene alterations that repeatedly occur in liver cancer are largely unknown. We aimed to identify metabolic genes that are consistently deregulated, and are of potential clinical significance in human hepatocellular carcinoma (HCC). We studied the expression of 2,761 metabolic genes in 8 microarray datasets comprising 521 human HCC tissues. Genes exclusively up-regulated or down-regulated in 6 or more datasets were defined as consistently deregulated. The consistent genes that correlated with tumor progression markers ( ECM2 and MMP9) (Pearson correlation P < .05) were used for Kaplan-Meier overall survival analysis in a patient cohort. We further compared proteomic expression of metabolic genes in 19 tumors vs adjacent normal liver tissues. We identified 634 consistent metabolic genes, ∼60% of which are not yet described in HCC. The down-regulated genes (n = 350) are mostly involved in physiologic hepatocyte metabolic functions (eg, xenobiotic, fatty acid, and amino acid metabolism). In contrast, among consistently up-regulated metabolic genes (n = 284) are those involved in glycolysis, pentose phosphate pathway, nucleotide biosynthesis, tricarboxylic acid cycle, oxidative phosphorylation, proton transport, membrane lipid, and glycan metabolism. Several metabolic genes (n = 434) correlated with progression markers, and of these, 201 predicted overall survival outcome in the patient cohort analyzed. Over 90% of the metabolic targets significantly altered at the protein level were similarly up- or down-regulated as in genomic profile. We provide the first exposition of the consistently altered metabolic genes in HCC and show that these genes are potentially relevant targets for onward studies in preclinical and clinical contexts.

  3. Chlorite alteration in aqueous solutions and uranium removal by altered chlorite

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eungyeong; Ahn, Hyangsig [Department of Earth and Environmental Sciences, Korea University, Anam-dong, Seongbuk-gu, Seoul 02841 (Korea, Republic of); Jo, Ho Young, E-mail: hyjo@korea.ac.kr [Department of Earth and Environmental Sciences, Korea University, Anam-dong, Seongbuk-gu, Seoul 02841 (Korea, Republic of); Ryu, Ji-Hun; Koh, Yong-Kwon [Korea Atomic Energy Research Institute, 1045 Daedeokdaero, Yuseong-gu, Daejeon 34057 (Korea, Republic of)

    2017-04-05

    Highlights: • Chlorite alteration and the U removal capacity of altered chlorite were investigated. • Initial pH affected more chlorite dissolution than ionic strength. • Chlorite dissolution at pH{sub o} = 3–8 was inversely proportional to the U removal capacity. • Chlorite dissolution at pH{sub o} = 10 was proportional to the U removal capacity. • The formation of Fe-containing secondary minerals affected the U removal capacity. - Abstract: Chlorite alteration and the U removal capacity of altered chlorite were investigated. Batch kinetic dissolution tests using clinochlore CCa-2 were conducted for 60 days in aqueous solutions of various pHs and ionic strengths. Batch sorption tests using these altered chlorite samples were conducted for 48 h with natural groundwater containing 3.06 × 10{sup −6} M U. Chlorite dissolution was influenced more by pH{sub o} than by the ionic strength of the solution. TEM analysis revealed Fe(oxy)hydroxide aggregates in the solid residue from the batch dissolution test with 0.1 M NaClO{sub 4} solution at pH{sub o} = 10. The U removal capacity of the reacted chlorite samples at pH{sub o} = 6–10 was higher than that of the reacted chlorite samples at pH{sub o} = 3. The degree of dissolution of chlorite samples reacted at pH{sub o} = 3–8 was inversely proportional to the U removal capacity, but that of chlorite samples reacted at pH{sub o} = 10 was proportional to the U removal capacity. The positive correlation between the U removal capacity and degree of chlorite dissolution at pH{sub o} = 10 might be due to the formation of Fe-containing secondary minerals and changes in the reactive sites.

  4. Fathers' experience of childbirth when non-progressive labour occurs and augmentation is established. A qualitative study

    DEFF Research Database (Denmark)

    Hasman, Kirsten; Kjaergaard, Hanne; Esbensen, Bente Appel

    2014-01-01

    as uncontrollable processes and (3) Relief about the decision of augmentation. The fathers had a rational approach and felt powerless when the process of labour was uncontrollable. They felt they were not able to help their partners in pain when non-progressive labour occurred. They experienced relief when......OBJECTIVE: Augmentation with oxytocin during labour has increased in Western obstetrics over the last few decades. The aim of this study was to describe how fathers experienced childbirth when non-progressive labour occurred and augmentation was established. METHOD: A qualitative descriptive design...... after experiencing the non-progressive labour, need directions from the midwives to carry out appropriate and usefull tasks....

  5. Naturally occurring radionuclides in food

    International Nuclear Information System (INIS)

    Djujic, I.

    1995-01-01

    The naturally occurring radionuclides are the major source of radiation exposure to humans. The principal way of natural radiation exposure is the inhalation of 222 Rn decay products (about 85% of the total). The remainder is equally divided between internally deposited radionuclides, cosmic and terrestrial sources. In the present study, the content of 40 K, 210 Pb, 226 Ra, 230 Th, 232 Th and 238 U in representative food samples (milk, pork, beef, potatoes, wheat and corn flour) and samples of different food items that do not represent entire national production but provide interesting additional data for approximative calculation of naturally occurring radionuclide intake is presented. Daily weight of food eaten, participation of food groups, as well as daily intake by food of mentioned naturally occurring radionuclides in the Serbian diet was obtained on the base of house hold budget surveys. The result obtained for daily intake estimates in mBq for Serbian population are 78.1 ( 40 K), 38.2( 210 Pb), 52.3( 226 Ra), 2.0( 230 Th) and 12.5( 238 U). (author)

  6. Depletion of key protein components of the RISC pathway impairs pre-ribosomal RNA processing.

    Science.gov (United States)

    Liang, Xue-Hai; Crooke, Stanley T

    2011-06-01

    Little is known about whether components of the RNA-induced silencing complex (RISC) mediate the biogenesis of RNAs other than miRNA. Here, we show that depletion of key proteins of the RISC pathway by antisense oligonucleotides significantly impairs pre-rRNA processing in human cells. In cells depleted of Drosha or Dicer, different precursors to 5.8S rRNA strongly accumulated, without affecting normal endonucleolytic cleavages. Moderate yet distinct processing defects were also observed in Ago2-depleted cells. Physical links between pre-rRNA and these proteins were identified by co-immunoprecipitation analyses. Interestingly, simultaneous depletion of Dicer and Drosha led to a different processing defect, causing slower production of 28S rRNA and its precursor. Both Dicer and Ago2 were detected in the nuclear fraction, and reduction of Dicer altered the structure of the nucleolus, where pre-rRNA processing occurs. Together, these results suggest that Drosha and Dicer are implicated in rRNA biogenesis.

  7. Thermal remediation alters soil properties - a review.

    Science.gov (United States)

    O'Brien, Peter L; DeSutter, Thomas M; Casey, Francis X M; Khan, Eakalak; Wick, Abbey F

    2018-01-15

    Contaminated soils pose a risk to human and ecological health, and thermal remediation is an efficient and reliable way to reduce soil contaminant concentration in a range of situations. A primary benefit of thermal treatment is the speed at which remediation can occur, allowing the return of treated soils to a desired land use as quickly as possible. However, this treatment also alters many soil properties that affect the capacity of the soil to function. While extensive research addresses contaminant reduction, the range and magnitude of effects to soil properties have not been explored. Understanding the effects of thermal remediation on soil properties is vital to successful reclamation, as drastic effects may preclude certain post-treatment land uses. This review highlights thermal remediation studies that have quantified alterations to soil properties, and it supplements that information with laboratory heating studies to further elucidate the effects of thermal treatment of soil. Notably, both heating temperature and heating time affect i) soil organic matter; ii) soil texture and mineralogy; iii) soil pH; iv) plant available nutrients and heavy metals; v) soil biological communities; and iv) the ability of the soil to sustain vegetation. Broadly, increasing either temperature or time results in greater contaminant reduction efficiency, but it also causes more severe impacts to soil characteristics. Thus, project managers must balance the need for contaminant reduction with the deterioration of soil function for each specific remediation project. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. The alteration of chromatin domains during damage repair induced by ionizing radiation

    International Nuclear Information System (INIS)

    Cress, A.E.; Olson, K.M.; Olson, G.B.

    1995-01-01

    Several groups previously have reported the ability of chromatin structure to influence the production of damage induced by ionizing radiation. The authors' interest has been to determine whether chromatin structural alterations exist after ionizing radiation during a repair interval. The earlier work investigated this question using biochemical techniques. The crosslinking of nuclear structural proteins to DNA after ionizing radiation was observed. In addition, they found that the chromatin structure in vitro as measured by sucrose density gradient sedimentation, was altered after ionizing radiation. These observations added to earlier studies in which digital imaging techniques showed an alteration in feulgen-positive DNA after irradiation prompted the present study. The object of this study was to detect whether the higher order structure of DNA into chromatin domains within interphase human cells was altered in interphase cells in response to a radiation induced damage. The present study takes advantage of the advances in the detection of chromatin domains in situ using DNA specific dyes and digital image processing of established human T and B cell lines

  9. Mitochondrial Optic Atrophy (OPA) 1 Processing Is Altered in Response to Neonatal Hypoxic-Ischemic Brain Injury

    Science.gov (United States)

    Baburamani, Ana A.; Hurling, Chloe; Stolp, Helen; Sobotka, Kristina; Gressens, Pierre; Hagberg, Henrik; Thornton, Claire

    2015-01-01

    Perturbation of mitochondrial function and subsequent induction of cell death pathways are key hallmarks in neonatal hypoxic-ischemic (HI) injury, both in animal models and in term infants. Mitoprotective therapies therefore offer a new avenue for intervention for the babies who suffer life-long disabilities as a result of birth asphyxia. Here we show that after oxygen-glucose deprivation in primary neurons or in a mouse model of HI, mitochondrial protein homeostasis is altered, manifesting as a change in mitochondrial morphology and functional impairment. Furthermore we find that the mitochondrial fusion and cristae regulatory protein, OPA1, is aberrantly cleaved to shorter forms. OPA1 cleavage is normally regulated by a balanced action of the proteases Yme1L and Oma1. However, in primary neurons or after HI in vivo, protein expression of YmelL is also reduced, whereas no change is observed in Oma1 expression. Our data strongly suggest that alterations in mitochondria-shaping proteins are an early event in the pathogenesis of neonatal HI injury. PMID:26393574

  10. Altered energy production, lowered antioxidant potential, and inflammatory processes mediate CNS damage associated with abuse of the psychostimulants MDMA and methamphetamine

    Science.gov (United States)

    Downey, Luke A.; Loftis, Jennifer M.

    2014-01-01

    Central nervous system (CNS) damage associated with psychostimulant dependence may be an ongoing, degenerative process with adverse effects on neuropsychiatric function. However, the molecular mechanisms regarding how altered energy regulation affects immune response in the context of substance use disorders are not fully understood. This review summarizes the current evidence regarding the effects of psychostimulant [particularly 3,4-methylenedioxy-N-methylamphetamine (MDMA) and methamphetamine] exposure on brain energy regulation, immune response, and neuropsychiatric function. Importantly, the neuropsychiatric impairments (e.g., cognitive deficits, depression, and anxiety) that persist following abstinence are associated with poorer treatment outcomes – increased relapse rates, lower treatment retention rates, and reduced daily functioning. Qualifying the molecular changes within the CNS according to the exposure and use patterns of specifically abused substances should inform the development of new therapeutic approaches for addiction treatment. PMID:24485894

  11. Altered Sensory Feedbacks in Pianist's Dystonia: the altered auditory feedback paradigm and the glove effect

    Directory of Open Access Journals (Sweden)

    Felicia Pei-Hsin Cheng

    2013-12-01

    Full Text Available Background: This study investigates the effect of altered auditory feedback (AAF in musician's dystonia (MD and discusses whether altered auditory feedback can be considered as a sensory trick in MD. Furthermore, the effect of AAF is compared with altered tactile feedback, which can serve as a sensory trick in several other forms of focal dystonia. Methods: The method is based on scale analysis (Jabusch et al. 2004. Experiment 1 employs synchronization paradigm: 12 MD patients and 25 healthy pianists had to repeatedly play C-major scales in synchrony with a metronome on a MIDI-piano with 3 auditory feedback conditions: 1. normal feedback; 2. no feedback; 3. constant delayed feedback. Experiment 2 employs synchronization-continuation paradigm: 12 MD patients and 12 healthy pianists had to repeatedly play C-major scales in two phases: first in synchrony with a metronome, secondly continue the established tempo without the metronome. There are 4 experimental conditions, among them 3 are the same altered auditory feedback as in Experiment 1 and 1 is related to altered tactile sensory input. The coefficient of variation of inter-onset intervals of the key depressions was calculated to evaluate fine motor control. Results: In both experiments, the healthy controls and the patients behaved very similarly. There is no difference in the regularity of playing between the two groups under any condition, and neither did AAF nor did altered tactile feedback have a beneficial effect on patients’ fine motor control. Conclusions: The results of the two experiments suggest that in the context of our experimental designs, AAF and altered tactile feedback play a minor role in motor coordination in patients with musicians' dystonia. We propose that altered auditory and tactile feedback do not serve as effective sensory tricks and may not temporarily reduce the symptoms of patients suffering from MD in this experimental context.

  12. Brain network alterations and vulnerability to simulated neurodegeneration in breast cancer.

    Science.gov (United States)

    Kesler, Shelli R; Watson, Christa L; Blayney, Douglas W

    2015-08-01

    Breast cancer and its treatments are associated with mild cognitive impairment and brain changes that could indicate an altered or accelerated brain aging process. We applied diffusion tensor imaging and graph theory to measure white matter organization and connectivity in 34 breast cancer survivors compared with 36 matched healthy female controls. We also investigated how brain networks (connectomes) in each group responded to simulated neurodegeneration based on network attack analysis. Compared with controls, the breast cancer group demonstrated significantly lower fractional anisotropy, altered small-world connectome properties, lower brain network tolerance to systematic region (node), and connection (edge) attacks and significant cognitive impairment. Lower tolerance to network attack was associated with cognitive impairment in the breast cancer group. These findings provide further evidence of diffuse white matter pathology after breast cancer and extend the literature in this area with unique data demonstrating increased vulnerability of the post-breast cancer brain network to future neurodegenerative processes. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Behavioural alterations are independent of sickness behaviour in chronic experimental Chagas disease.

    Science.gov (United States)

    Vilar-Pereira, Glaucia; Ruivo, Leonardo Alexandre de Souza; Lannes-Vieira, Joseli

    2015-12-01

    The existence of the nervous form of Chagas disease is a matter of discussion since Carlos Chagas described neurological disorders, learning and behavioural alterations in Trypanosoma cruzi-infected individuals. In most patients, the clinical manifestations of the acute phase, including neurological abnormalities, resolve spontaneously without apparent consequence in the chronic phase of infection. However, chronic Chagas disease patients have behavioural changes such as psychomotor alterations, attention and memory deficits, and depression. In the present study, we tested whether or not behavioural alterations are reproducible in experimental models. We show that C57BL/6 mice chronically infected with the Colombian strain of T. cruzi (150 days post-infection) exhibit behavioural changes as (i) depression in the tail suspension and forced swim tests, (ii) anxiety analysed by elevated plus maze and open field test sand and (iii) motor coordination in the rotarod test. These alterations are neither associated with neuromuscular disorders assessed by the grip strength test nor with sickness behaviour analysed by temperature variation sand weight loss. Therefore, chronically T. cruzi-infected mice replicate behavioural alterations (depression and anxiety) detected in Chagas disease patients opening an opportunity to study the interconnection and the physiopathology of these two biological processes in an infectious scenario.

  14. A novel capacitive micro-accelerometer with grid strip capacitances and sensing gap alterable capacitances

    International Nuclear Information System (INIS)

    Dong Linxi; Chen Jindan; Huo Weihong; Li Yongjie; Sun Lingling; Yan Haixia

    2009-01-01

    The comb capacitances fabricated by deep reactive ion etching (RIE) process have high aspect ratio which is usually smaller than 30: 1 for the complicated process factors, and the combs are usually not parallel due to the well-known micro-loading effect and other process factors, which restricts the increase of the seismic mass by increasing the thickness of comb to reduce the thermal mechanical noise and the decrease of the gap of the comb capacitances for increasing the sensitive capacitance to reduce the electrical noise. Aiming at the disadvantage of the deep RIE, a novel capacitive micro-accelerometer with grid strip capacitances and sensing gap alterable capacitances is developed. One part of sensing of inertial signal of the micro-accelerometer is by the grid strip capacitances whose overlapping area is variable and which do not have the non-parallel plate's effect caused by the deep RIE process. Another part is by the sensing gap alterable capacitances whose gap between combs can be reduced by the actuators. The designed initial gap of the alterable comb capacitances is relatively large to depress the effect of the maximum aspect ratio (30 : 1) of deep RIE process. The initial gap of the capacitance of the actuator is smaller than the one of the comb capacitances. The difference between the two gaps is the initial gap of the sensitive capacitor. The designed structure depresses greatly the requirement of deep RIE process. The effects of non-parallel combs on the accelerometer are also analyzed. The characteristics of the micro-accelerometer are discussed by field emission microscopy (FEM) tool ANSYS. The tested devices based on slide-film damping effect are fabricated, and the tested quality factor is 514, which shows that grid strip capacitance design can partly improve the resolution and also prove the feasibility of the designed silicon-glass anodically bonding process.

  15. Hepatitis B Virus Core Protein Dephosphorylation Occurs during Pregenomic RNA Encapsidation.

    Science.gov (United States)

    Zhao, Qiong; Hu, Zhanying; Cheng, Junjun; Wu, Shuo; Luo, Yue; Chang, Jinhong; Hu, Jianming; Guo, Ju-Tao

    2018-07-01

    Hepatitis B virus (HBV) core protein consists of an N-terminal assembly domain and a C-terminal domain (CTD) with seven conserved serines or threonines that are dynamically phosphorylated/dephosphorylated during the viral replication cycle. Sulfamoylbenzamide derivatives are small molecular core protein allosteric modulators (CpAMs) that bind to the heteroaryldihydropyrimidine (HAP) pocket between the core protein dimer-dimer interfaces. CpAM binding alters the kinetics and pathway of capsid assembly and can result in the formation of morphologically "normal" capsids devoid of viral pregenomic RNA (pgRNA) and DNA polymerase. In order to investigate the mechanism underlying CpAM inhibition of pgRNA encapsidation, we developed an immunoblotting assay that can resolve core protein based on its phosphorylation status and demonstrated, for the first time, that core protein is hyperphosphorylated in free dimers and empty capsids from both mock-treated and CpAM-treated cells but is hypophosphorylated in pgRNA- and DNA-containing nucleocapsids. Interestingly, inhibition of pgRNA encapsidation by a heat shock protein 90 (HSP90) inhibitor prevented core protein dephosphorylation. Moreover, core proteins with point mutations at the wall of the HAP pocket, V124A and V124W, assembled empty capsids and nucleocapsids with altered phosphorylation status. The results thus suggest that core protein dephosphorylation occurs in the assembly of pgRNA and that interference with the interaction between core protein subunits at dimer-dimer interfaces during nucleocapsid assembly alters not only capsid structure, but also core protein dephosphorylation. Hence, inhibition of pgRNA encapsidation by CpAMs might be due to disruption of core protein dephosphorylation during nucleocapsid assembly. IMPORTANCE Dynamic phosphorylation of HBV core protein regulates multiple steps of viral replication. However, the regulatory function was mainly investigated by phosphomimetic mutagenesis, which

  16. Occurrence and Mineralogical Characteristics of Tremolite Asbestos Occurred in Boryeong area, Chungnam, South Korea

    Science.gov (United States)

    Yoon, K.; Hwang, J.; Oh, J.; Lee, H.

    2009-12-01

    Abandoned tremolite mines, which had been exploited for several decades since 1930, are distributed in Boryeong, Chungnam. It is known that tremolite asbestos is approximately 100 times more harmful than chrysotile asbestos. Recently, it become a regional social problem because lung disease (mesothelioma and lung cancer) suspect patients are largely found among the residents of the mining area. Therefore, Korean government making every endeavor to remove asbestos risk in the area. However, there is insufficiency geological and mineralogical studies for tremolite asbestos. In the present study, the occurrence and mineralogical characteristics of tremolite asbestos were studied using polarization microscope, XRD, XRF, EPMA, SEM and TEM. Mica-schist of precambrian metasedimentary rock, which is widely distributed in the area, is the host rock of tremolite deposits. The rocks are largely disturbed by faults and folds, and shows sudden changes in strike and slope of strata. Tremolite ore bodies, which show relatively light colored, mainly occur as stratiform or veinlet and some occurs in brecciated rock fragments. Tremolite is a major asbestos mineral, and chrysotile, talc, mica, chlorite and quartz occurs as associated minerals. Considerable amount of ore containing pure tremolite is found, and ores having mineral assemblages of tremolite+talc, tremolite+quartz and chrysotile+talc also occurs. From optical microscope observations, most tremolites are asbestos from that meets to the criterion (length > 5 μm, diameter 3:1) defined by the international organization (WHO, ILO), but non-asbestos form tremolites are also included. Most asbestos form tremolites have the size range of 1.0-2.0 μm width and 5-10 μm length. The length can be shorten with crushing experiments, but the width remains unchanged. Non-asbestos form hardly change to asbestos form by mechanical crushing. From comprehensive studies for geological occurrence and mineral assemblage, it is considered that

  17. Mid-ocean ridge serpentinite in the Puerto Rico Trench: Accretion, alteration, and subduction of Cretaceous seafloor in the Atlantic Ocean

    Science.gov (United States)

    Klein, F.; Marschall, H.; Bowring, S. A.; Horning, G.

    2016-12-01

    Serpentinite is believed to be one of the main carriers of water and fluid mobile elements into subduction zones, but direct evidence for serpentinite subduction has been elusive. The Antilles island arc is one of only two subduction zones worldwide that recycles slow-spreading oceanic lithosphere where descending serpentinite is both exposed by faulting and directly accessible on the seafloor. Here we examined serpentinized peridotites dredged from the North Wall of the Puerto Rico Trench (NWPRT) to assess their formation and alteration history and discuss geological ramifications resulting from their emplacement and subduction. Lithospheric accretion and serpentinization occurred, as indicated by U-Pb geochronology of hydrothermally altered zircon, at the Cretaceous Mid-Atlantic Ridge (CMAR). In addition to lizardite-rich serpentinites with pseudomorphic textures after olivine and pyroxene typical for static serpentinization at slow spreading mid-ocean ridges, recovered samples include non-pseudomorphic antigorite-rich serpentinites that are otherwise typically associated with peridotite at convergent plate boundaries. Antigorite-serpentinites have considerably lower Fe(III)/Fetot and lower magnetic susceptibilities than lizardite-serpentinites with comparable Fetot contents. Rare earth element (REE) contents of lizardite-serpentinites decrease linearly with increasing Fe(III)/Fetot of whole rock samples, suggesting that oxidation during seafloor weathering of serpentinite releases REEs to seawater. Serpentinized peridotites recorded multifaceted igneous and high- to low-temperature hydrothermal processes that involved extensive chemical, physical, and mineralogical modifications of their peridotite precursors with strong implications for our understanding of the accretion, alteration, and subduction of slow-spreading oceanic lithosphere.

  18. Evolution of the alteration process in time of granitic materials from Valdemorillo quarries used in built heritage, Madrid, Spain

    Science.gov (United States)

    Alvarez de Buergo, M.; Fort, R.; Perez-Monserrat, E. M.

    2012-04-01

    Alteration of building materials used for heritage construction already starts in the quarries, where materials are subjected to both natural alteration and anthropic decay, this latter caused by the rock extracting, cutting and carving processes. Once the materials are placed in the building, they are exposed to other agents that accelerate their decay, especially if they are exposed to aggressive environments. Materials petrophysical properties tend to vary according to the alteration degree they have experienced, the longer they have been exposed to decay agents, the greater the properties change. Surface hardness of granitic rocks tend to diminish when they deteriorate, increasing its porosity, which usually is reflected on a decrease of the ultrasound propagation velocity measurements. Ultrasound velocity and surface hardness were measured in 200 monzogranite ashlars use to build the Assumption of Our Lady church (Valdemorillo, Madrid, Spain). Ultrasound velocity was measured using the indirect transmission mode, with 54 kHz frequency transductors, and surface hardness by means of the Schmidt hammer rebound tester. This monument was erected in different building stages. The starting point was a Mozarab or Visigoth defensive tower (8th century). Templars readapt it to a castle-convent (12th and 14th centuries), the tower being converted into a higher bell-tower. During the 14th-15th centuries the Cistercian Order made significant modifications of the complex, being the construction of the Chapter House one of the last enlargements during the 17th century. The quarries located in the surroundings of the monument were used for the first building stages. In the recent fronts of these quarries that have been used along the 20th century, ultrasound and hardness measurements were performed to obtain the values of these parameters in unaltered materials to compare them to those measured in ashlars from different constructive periods. A total of 50 recent front

  19. Proximity to Delivery Alters Insulin Sensitivity and Glucose Metabolism in Pregnant Mice.

    Science.gov (United States)

    Musial, Barbara; Fernandez-Twinn, Denise S; Vaughan, Owen R; Ozanne, Susan E; Voshol, Peter; Sferruzzi-Perri, Amanda N; Fowden, Abigail L

    2016-04-01

    In late pregnancy, maternal insulin resistance occurs to support fetal growth, but little is known about insulin-glucose dynamics close to delivery. This study measured insulin sensitivity in mice in late pregnancy at day 16 (D16) and near term at D19. Nonpregnant (NP) and pregnant mice were assessed for metabolite and hormone concentrations, body composition by DEXA, tissue insulin signaling protein abundance by Western blotting, glucose tolerance and utilization, and insulin sensitivity using acute insulin administration and hyperinsulinemic-euglycemic clamps with [(3)H]glucose infusion. Whole-body insulin resistance occurred in D16 pregnant dams in association with basal hyperinsulinemia, insulin-resistant endogenous glucose production, and downregulation of several proteins in hepatic and skeletal muscle insulin signaling pathways relative to NP and D19 values. Insulin resistance was less pronounced at D19, with restoration of NP insulin concentrations, improved hepatic insulin sensitivity, and increased abundance of hepatic insulin signaling proteins. At D16, insulin resistance at whole-body, tissue, and molecular levels will favor fetal glucose acquisition, while improved D19 hepatic insulin sensitivity will conserve glucose for maternal use in anticipation of lactation. Tissue sensitivity to insulin, therefore, alters differentially with proximity to delivery in pregnant mice, with implications for human and other species. © 2016 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

  20. Hydrothermal alteration in the Matok Igneous Complex, Southern Marginal Zone of the Limpopo Belt, South Africa

    International Nuclear Information System (INIS)

    Sieber, T.; Van Reenen, D.D.; Barton, J.M.

    1991-01-01

    Ductile shear zones associated with the 2700 to 2650 Ma Limpopo Orogeny locally contained gold mineralization. Some of these shear zones were reactivated under brittle conditions and contain zones of hydrothermal alteration that are of potential economic significance. Within the approximately 2670 Ma Matok Complex, two examples of this shear zone controlled alteration are exposed, the Dwars River and Sand River alteration zones. The granitic rocks of this Complex experienced early selective sericitization of plagioclase and the subsequent development of perthitic porphyroblasts. This early regional alteration was overprinted along brittle shear zones by pervasive propylitization and vein controlled quartz-albite alteration. The setting, composition, and the age of the Matok Complex make it a possible source for Archaean gold mineralization. The Dwars River and Sand River alteration zones are characterized by the absence of significant gold mineralization. The pattern of wall-rock alteration indicates that the hydrothermal processes were different from typical Archaean lode gold deposits. P-T conditions during the shear-zone controlled alteration were less than 400 degrees C and 1,9 - 2,8 kb. The shear zone hosted alteration could have taken place anytime between emplacement of the Matok Complex and about 1315 Ma ago. 35 refs., 10 figs., 4 tabs

  1. Reference Material IAEA 434: Naturally Occurring Radionuclides in Phosphogypsum

    International Nuclear Information System (INIS)

    2010-01-01

    Phosphogypsum is generated as a by-product of the phosphoric acid based fertilizer industry. The discharge of phosphogypsum on earth surface deposits is a potential source of enhanced natural radiation and heavy metals, and the resulting environmental impact should be considered carefully to ensure safety and compliance with environmental regulations. In addition, phosphogypsum can be used to make several building materials and it is used in agriculture as a conditioner to maintain soil productivity in areas where soils are poor and erode easily. A reliable determination of naturally occurring radionuclides in phosphogypsum is necessary to comply with the radiation protection and environmental regulations. The IAEA-434 will assist laboratories in the IAEA Member States in validating their analytical methods for the determination of naturally occurring radionuclides in phosphogypsum and to control the quality of the produced analytical results. Reference values for the massic activities and associated standard uncertainties were established for: Pb-210, Ra-226, Th-230, U-234 and U-238. During sample production and certification, the requirements for reference material production and certification as stated in ISO guides 34 and 35 were taken into account. This report summarizes the preparation and certification process

  2. Alteration dependent physical-mechanical properties of quartz-diorite building stones

    Directory of Open Access Journals (Sweden)

    Masoud Torkan

    2016-12-01

    Full Text Available The microscopic and geomechanical properties of igneous building stones include the level of alteration, presence of micro cracks, peak strength, porosity, proportion of detrimental minerals, etc. Porosity is reportedly of a devastating impact on the peak strength of igneous rocks. The quartz diorite rock samples in this study were selected from five quarries in Natanz, Iran and subject to microscopic and geomechanical investigations. The level of alteration and the minerals detrimental to the strength of the samples were identified from thin sections. Therefore, the geomechanical tests upon density, porosity, durability index, the Brazilian, and triaxial tests were conducted as per ISRM standards. The findings from microscopic studies reveal that alteration is of more intense impact on rock peak strength compared to that of porosity. The results were compared to standard values and a qualitative correlation between strength and microscopic properties was detected accentuating the importance of microscopic studies on construction stones. The correlation thereupon may be adopted in the exploration, exploitation, and process of construction stones to avoid heavy expenditures and damage to the environment.

  3. Origins of altered reinforcement effects in ADHD

    Directory of Open Access Journals (Sweden)

    Tripp Gail

    2009-02-01

    Full Text Available Abstract Attention-deficit/hyperactivity disorder (ADHD, characterized by hyperactivity, impulsiveness and deficient sustained attention, is one of the most common and persistent behavioral disorders of childhood. ADHD is associated with catecholamine dysfunction. The catecholamines are important for response selection and memory formation, and dopamine in particular is important for reinforcement of successful behavior. The convergence of dopaminergic mesolimbic and glutamatergic corticostriatal synapses upon individual neostriatal neurons provides a favorable substrate for a three-factor synaptic modification rule underlying acquisition of associations between stimuli in a particular context, responses, and reinforcers. The change in associative strength as a function of delay between key stimuli or responses, and reinforcement, is known as the delay of reinforcement gradient. The gradient is altered by vicissitudes of attention, intrusions of irrelevant events, lapses of memory, and fluctuations in dopamine function. Theoretical and experimental analyses of these moderating factors will help to determine just how reinforcement processes are altered in ADHD. Such analyses can only help to improve treatment strategies for ADHD.

  4. TCDD alters medial epithelial cell differentiation during palatogenesis

    International Nuclear Information System (INIS)

    Abbott, B.D.; Birnbaum, L.S.

    1989-01-01

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a widely distributed, persistent environmental contaminant that is teratogenic in mice, where it induces hydronephrosis and cleft palate. The incidence of clefting has been shown to be dose dependent after exposure on either gestation Day (GD) 10 or 12, although the embryo is more susceptible on GD 12. TCDD-exposed palatal shelves meet but do not fuse, and programmed cell death of the medial epithelial cells is inhibited. The mechanism of action through which TCDD alters the program of medial cell development has not been examined in earlier studies, and it is not known whether the mechanism is the same regardless of the dose or developmental stage of exposure. In this study, C57BL/6N mice, a strain sensitive to TCDD, were dosed orally on GD 10 or 12 with 0, 6, 12, 24, or 30 micrograms/kg body wt, in 10 ml corn oil/kg. Embryonic palatal shelves were examined on GD 14, 15, or 16. The degree of palatal closure, epithelial surface morphology, and cellular ultrastructure, the incorporation of [3H]TdR, the expression of EGF receptors, and the binding of 125I-EGF were assessed. After exposure on GD 10 or 12, TCDD altered the differentiation pathway of the medial epithelial cells. The palatal shelves were of normal size and overall morphology, but fusion of the medial epithelia of the opposing shelves did not occur. TCDD prevented programmed cell death of the medial peridermal cells. The expression of EGF receptors by medial cells continued through Day 16 and the receptors were able to bind ligand. The medial cells differentiated into a stratified, squamous, keratinizing epithelium. The shift in phenotype to an oral-like epithelium occurred after exposure on either GD 10 or 12. At the lower dose (6 micrograms/kg), fewer cleft palates were produced, but those shelves which did respond had a fully expressed shift in differentiation

  5. Fundamental aspects on ion-beam surface modification: defect production and migration processes

    International Nuclear Information System (INIS)

    Rehn, L.E.; Averback, R.S.; Okamoto, P.R.

    1984-09-01

    Ion-beam modification of metals is generating increasing scientific interest not only because it has exciting technological potential, but also because it has raised fundamental questions concerning radiation-induced diffusion processes. In addition to the implanted species, several defect production and migration mechanisms contribute to changes in the near-surface composition of an alloy during ion bombardment, e.g., atoms exchange positions via displacements and replacement sequences; preferential sputtering effects arise; radiation-enhanced diffusion and radiation-induced segregation occur. The latter two defect migration mechanisms are of particular significance since they can alter the composition to depths which are much greater than the implanted ion range. By altering various parameters such as irradiation temperature, ion mass, energy, and current density, and initial alloying distributions, a rich variety of near-surface composition profiles can be created. We have utilized changes in ion mass and energy, and irradiation temperature to distinguish defect production from defect migration effects. Experimental results are presented which provide a guide to the relative efficiencies of different mechanisms under various irradiation conditions. 46 references

  6. Life History Responses and Feeding Behavior of Microcrustacea in Altered Gravity - Applicability in Bioregenerative Life Support Systems (BLSS)

    Science.gov (United States)

    Fischer, Jessica; Schoppmann, Kathrin; Laforsch, Christian

    2017-06-01

    Manned space missions, as for example to the planet Mars, are a current objective in space exploration. During such long-lasting missions, aquatic bioregenerative life support systems (BLSS) could facilitate independence of resupply from Earth by regenerating the atmosphere, purifying water, producing food and processing waste. In such BLSS, microcrustaceans could, according to their natural role in aquatic ecosystems, link oxygen liberating, autotrophic algae and higher trophic levels, such as fish. However, organisms employed in BLSS will be exposed to high acceleration (hyper- g) during launch of spacecrafts as well as to microgravity (μ g) during space travel. It is thus essential that these organisms survive, perform and reproduce under altered gravity conditions. In this study we present the first data in this regard for the microcrustaceas Daphnia magna and Heterocypris incongruens. We found that after hyper- g exposure (centrifugation) approximately one third of the D. magna population died within one week (generally indicating that possible belated effects have to be considered when conducting and interpreting experiments during which hyper- g occurs). However, suchlike and even higher losses could be countervailed by the surviving daphnids' unaltered high reproductive capacity. Furthermore, we can show that foraging and feeding behavior of D. magna (drop tower) and H. incongruens (parabolic flights) are rarely altered in μ g. Our results thus indicate that both species are suitable candidates for BLSS utilized in space.

  7. Biogeochemical alteration of dissolved organic material in the Cape Fear River Estuary as a function of freshwater discharge

    Science.gov (United States)

    Dixon, Jennifer L.; Helms, John R.; Kieber, Robert J.; Avery, G. Brooks

    2014-08-01

    This study presents the first extensive examination of the controls on optical properties of chromophoric dissolved organic matter (CDOM) within the Cape Fear River Estuary (CFRE) utilizing spectral slope ratios (SR). The application of SUVA254 values, absorption spectral slopes (S) and SR values has presented a distinct opportunity to observe compositional changes in CDOM in the CFRE that was not possible using bulk DOC and aCDOM(350) values alone. By comparing estuarine trends in CDOM spectral shape during both normal and historically low flow conditions, we found that diagenetic processing of CDOM in the CFRE is controlled primarily by riverine discharge rates. These findings suggest that the chromophoric fraction of DOM is altered during estuarine transport under low flow regimes but reaches the coastal ocean relatively unaltered under higher flow conditions. This highlights the tendency for autochthonous sources of DOC to offset photochemical losses and indicates that in situ DOC production can significantly contribute to the overall carbon load if discharge is low or sufficient biogeochemical alteration of the terrestrial DOM end-member occurs. This provides new insight into the usefulness of these optical properties into understanding the cycling, fate and transport of CDOM to the coastal ocean. SR values provide a simple but potentially powerful tool in understanding the flux, transport and impact of terrestrially derived organic material deposited in the coastal ocean.

  8. CoBOP: Microbial Biofilms: A Parameter Altering the Apparent Optical Properties of Sediments, Seagrasses and Surfaces

    Science.gov (United States)

    2002-09-30

    CoBOP: Microbial Biofilms: A Parameter Altering the Apparent Optical Properties of Sediments, Seagrasses and Surfaces Alan W. Decho Department...TITLE AND SUBTITLE CoBOP: Microbial Biofilms: A Parameter Altering the Apparent Optical Properties of Sediments, Seagrasses and Surfaces 5a. CONTRACT...structures produced by bacteria. Their growth appears to depend on biofilm processes and light distributions ( photosynthesis ). Therefore, the data acquired

  9. Regular exercise training reverses ectonucleotidase alterations and reduces hyperaggregation of platelets in metabolic syndrome patients.

    Science.gov (United States)

    Martins, Caroline Curry; Bagatini, Margarete Dulce; Cardoso, Andréia Machado; Zanini, Daniela; Abdalla, Fátima Husein; Baldissarelli, Jucimara; Dalenogare, Diéssica Padilha; Farinha, Juliano Boufleur; Schetinger, Maria Rosa Chitolina; Morsch, Vera Maria

    2016-02-15

    Alterations in the activity of ectonucleotidase enzymes have been implicated in cardiovascular diseases, whereas regular exercise training has been shown to prevent these alterations. However, nothing is known about it relating to metabolic syndrome (MetS). We investigated the effect of exercise training on platelet ectonucleotidase enzymes and on the aggregation profile of MetS patients. We studied 38 MetS patients who performed regular concurrent exercise training for 30 weeks. Anthropometric measurements, biochemical profiles, hydrolysis of adenine nucleotides in platelets and platelet aggregation were collected from patients before and after the exercise intervention as well as from individuals of the control group. An increase in the hydrolysis of adenine nucleotides (ATP, ADP and AMP) and a decrease in adenosine deamination in the platelets of MetS patients before the exercise intervention were observed (Pexercise training (Pexercise training prevented platelet hyperaggregation in addition to decrease the classic cardiovascular risks. An alteration of ectonucleotidase enzymes occurs during MetS, whereas regular exercise training had a protective effect on these enzymes and on platelet aggregation. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Dissolution and alteration of uraninite under reducing conditions

    International Nuclear Information System (INIS)

    Janeczek, J.; Ewing, R.C.

    1992-01-01

    The behavior of uraninite under hydrothermal, reducung conditions is discussed on the basis of data in the literature and the authors' investigation of samples from two natural analogue sites: Oklo, Gabon and Cigar Lake, Canada. Uraninite under reducing conditions, in the presence of saline hydrothermal solutions may be altered through dissolution, preferential loss of lead and/or Y + HREE, and coffinitization. Textural features indicative of dissolution or uraninite include embayed grain boundaries, corroded relicts of uraninite embedded in a clay matrix, and replacement of uraninite by clays and sulfides. The alteration textures and phase chemistries at Oklo and Cigar Lake are remarkably similar. Dissolution of uraninite at Cigar Lake and Oklo was associated with the precipitation or illite and was probably caused by saline, uraninite moderately acidic solutions at approximately 200deg C. Increased oxygen fugacity may have occured locally due to release of excess oxygen from uraninite during dissolution or by α-radiolysis of the solution. The formation of Pb-rich (up to 18 wt% Pb, uraninite-I) and Pb-depleted (approximately 7-8 wt% Pb, uraninite-II) uraninites at both Oklo and Cigar Lake resulted from the loss of Pb due to predominantly episodic volume diffusion related to regional geologic events. Lead loss was not associated with U mobilization. In addition to uraninite dissolution, coffinitization resulted in U, Pb and REE release. (orig.)

  11. Acid Sulfate Alteration on Mars

    Science.gov (United States)

    Ming, D. W.; Morris, R. V.

    2016-01-01

    A variety of mineralogical and geochemical indicators for aqueous alteration on Mars have been identified by a combination of surface and orbital robotic missions, telescopic observations, characterization of Martian meteorites, and laboratory and terrestrial analog studies. Acid sulfate alteration has been identified at all three landing sites visited by NASA rover missions (Spirit, Opportunity, and Curiosity). Spirit landed in Gusev crater in 2004 and discovered Fe-sulfates and materials that have been extensively leached by acid sulfate solutions. Opportunity landing on the plains of Meridiani Planum also in 2004 where the rover encountered large abundances of jarosite and hematite in sedimentary rocks. Curiosity landed in Gale crater in 2012 and has characterized fluvial, deltaic, and lacustrine sediments. Jarosite and hematite were discovered in some of the lacustrine sediments. The high elemental abundance of sulfur in surface materials is obvious evidence that sulfate has played a major role in aqueous processes at all landing sites on Mars. The sulfate-rich outcrop at Meridiani Planum has an SO3 content of up to 25 wt.%. The interiors of rocks and outcrops on the Columbia Hills within Gusev crater have up to 8 wt.% SO3. Soils at both sites generally have between 5 to 14 wt.% SO3, and several soils in Gusev crater contain around 30 wt.% SO3. After normalization of major element compositions to a SO3-free basis, the bulk compositions of these materials are basaltic, with a few exceptions in Gusev crater and in lacustrine mudstones in Gale crater. These observations suggest that materials encountered by the rovers were derived from basaltic precursors by acid sulfate alteration under nearly isochemical conditions (i.e., minimal leaching). There are several cases, however, where acid sulfate alteration minerals (jarosite and hematite) formed in open hydrologic systems, e.g., in Gale crater lacustrine mudstones. Several hypotheses have been suggested for the

  12. Study of nuclear glasses alteration gel and synthesis of some model gels

    International Nuclear Information System (INIS)

    Ricol, S.

    1995-01-01

    This work deals with the general problem of alteration of the reference nuclear glass R7T7. Attention is paid particularly to the altered layer formed at the glass surface during alteration process. In opposition to previous works, related essentially to glass dissolution kinetics based on chemical analyses of lixiviated elements, this thesis deals with alteration problems through structural studies of the reference glass and derived gel. This approach allows the determination of mechanisms for the gel formation and a better understanding of the behaviour of glasses towards lixiviation. Both approaches appeared complementary. Based on several spectroscopic techniques, this work showed the particular role of cations such as calcium, zirconium and iron. Studies of silica-based synthetic gels showed the synergic effect of formers cation and of one highly coordinated cation. The variation of the wavenumber related to Si-O-Si asymmetric stretching vibration can be correlated to O/Si ratio for ternary systems Si/Na/Zr. On the contrary, the Si losses of the materials depend on the number of non-bridging oxygen atoms. In the perspective of long-term behaviour, the alteration gel presents better characteristics than initial glass. It is therefore a highly stable material in static conditions. In the same way, synthetic gels are materials with very low solubilities (much lower than the alteration gel) and could be used as confining matrices. (authors). refs., 71 figs., 37 tabs

  13. DNA fingerprinting techniques for the analysis of genetic and epigenetic alterations in colorectal cancer.

    Science.gov (United States)

    Samuelsson, Johanna K; Alonso, Sergio; Yamamoto, Fumiichiro; Perucho, Manuel

    2010-11-10

    Genetic somatic alterations are fundamental hallmarks of cancer. In addition to point and other small mutations targeting cancer genes, solid tumors often exhibit aneuploidy as well as multiple chromosomal rearrangements of large fragments of the genome. Whether somatic chromosomal alterations and aneuploidy are a driving force or a mere consequence of tumorigenesis remains controversial. Recently it became apparent that not only genetic but also epigenetic alterations play a major role in carcinogenesis. Epigenetic regulation mechanisms underlie the maintenance of cell identity crucial for development and differentiation. These epigenetic regulatory mechanisms have been found substantially altered during cancer development and progression. In this review, we discuss approaches designed to analyze genetic and epigenetic alterations in colorectal cancer, especially DNA fingerprinting approaches to detect changes in DNA copy number and methylation. DNA fingerprinting techniques, despite their modest throughput, played a pivotal role in significant discoveries in the molecular basis of colorectal cancer. The aim of this review is to revisit the fingerprinting technologies employed and the oncogenic processes that they unveiled. 2010 Elsevier B.V. All rights reserved.

  14. Video game players show more precise multisensory temporal processing abilities.

    Science.gov (United States)

    Donohue, Sarah E; Woldorff, Marty G; Mitroff, Stephen R

    2010-05-01

    Recent research has demonstrated enhanced visual attention and visual perception in individuals with extensive experience playing action video games. These benefits manifest in several realms, but much remains unknown about the ways in which video game experience alters perception and cognition. In the present study, we examined whether video game players' benefits generalize beyond vision to multisensory processing by presenting auditory and visual stimuli within a short temporal window to video game players and non-video game players. Participants performed two discrimination tasks, both of which revealed benefits for video game players: In a simultaneity judgment task, video game players were better able to distinguish whether simple visual and auditory stimuli occurred at the same moment or slightly offset in time, and in a temporal-order judgment task, they revealed an enhanced ability to determine the temporal sequence of multisensory stimuli. These results suggest that people with extensive experience playing video games display benefits that extend beyond the visual modality to also impact multisensory processing.

  15. Alterations in brain-derived neurotrophic factor in the mouse hippocampus following acute but not repeated benzodiazepine treatment.

    Directory of Open Access Journals (Sweden)

    Stephanie C Licata

    Full Text Available Benzodiazepines (BZs are safe drugs for treating anxiety, sleep, and seizure disorders, but their use also results in unwanted effects including memory impairment, abuse, and dependence. The present study aimed to reveal the molecular mechanisms that may contribute to the effects of BZs in the hippocampus (HIP, an area involved in drug-related plasticity, by investigating the regulation of immediate early genes following BZ administration. Previous studies have demonstrated that both brain derived neurotrophic factor (BDNF and c-Fos contribute to memory- and abuse-related processes that occur within the HIP, and their expression is altered in response to BZ exposure. In the current study, mice received acute or repeated administration of BZs and HIP tissue was analyzed for alterations in BDNF and c-Fos expression. Although no significant changes in BDNF or c-Fos were observed in response to twice-daily intraperitoneal (i.p. injections of diazepam (10 mg/kg + 5 mg/kg or zolpidem (ZP; 2.5 mg/kg + 2.5 mg/kg, acute i.p. administration of both triazolam (0.03 mg/kg and ZP (1.0 mg/kg decreased BDNF protein levels within the HIP relative to vehicle, without any effect on c-Fos. ZP specifically reduced exon IV-containing BDNF transcripts with a concomitant increase in the association of methyl-CpG binding protein 2 (MeCP2 with BDNF promoter IV, suggesting that MeCP2 activity at this promoter may represent a ZP-specific mechanism for reducing BDNF expression. ZP also increased the association of phosphorylated cAMP response element binding protein (pCREB with BDNF promoter I. Future work should examine the interaction between ZP and DNA as the cause for altered gene expression in the HIP, given that BZs can enter the nucleus and intercalate into DNA directly.

  16. SON68 glass alteration enhanced by magnetite

    Energy Technology Data Exchange (ETDEWEB)

    Godon, Nicole; Gin, Stephane; Rebiscoul, Diane; Frugier, Pierre [CEA, DEN-Marcoule, F30207, Bagnols-sur-Ceze (France)

    2013-07-01

    This paper reports experimental and modeling results of SON68 glass / magnetite interactions while in contact with synthetic groundwater from a clay environment. It is shown that magnetite enhances glass alteration, first by the sorption of Si released from the glass onto magnetite surfaces, then by a second process that could be the precipitation of an iron silicate mineral or the transformation of magnetite into a more reactive phase like hematite or goethite. This study globally suggests a detrimental effect of magnetite on the long-term durability of nuclear glass in geological disposal conditions. (authors)

  17. Report of the Committee of inquiry into a fire which occurred on 18 March 1987 in a radioisotope processing cell, Building 54 at the Lucas Heights Research Laboratories

    International Nuclear Information System (INIS)

    1987-01-01

    At about 1745 hours on Wednesday, 18 March 1987 a fire occurred in a small charcoal filter inside a processing cell (hot cell) in Building 54 at the Lucas Heights Research Laboratories (LHRL). This cell was being used to process irradiated uranium to separate the radioactive isotope molybdenum-99. Some radioactive contamination escaped from the hot cell into the operating area and three AAEC officers were found to have minor radioactive contamination on their skin/hair. The majority of the radioactive material released from the fire was trapped by the main filters outside the cell. The total amounts of radioactive noble gas and of radioiodine released to the environment during the week in which the fire occurred were within the normal range of discharge and were 53% and 2.1%, respectively, of the weekly limit authorised by the NSW Department of Health. On the evidence available to it, the Committee concludes that the fire was caused by spontaneous combustion in the charcoal filter used to trap radioactive gases released by the operations in the hot cell; the mechanism causing the fire cannot be clearly established at this stage; no member of AAEC staff, NSW emergency services personnel or the general public suffered, or will suffer, any adverse health effects from radioactivity as a result of the accident

  18. Low-temperature aqueous alteration on the CR chondrite parent body: Implications from in situ oxygen-isotope analyses

    Science.gov (United States)

    Jilly-Rehak, Christine E.; Huss, Gary R.; Nagashima, Kazu; Schrader, Devin L.

    2018-02-01

    The presence of hydrated minerals in chondrites indicates that water played an important role in the geologic evolution of the early Solar System; however, the process of aqueous alteration is still poorly understood. Renazzo-like carbonaceous (CR) chondrites are particularly well-suited for the study of aqueous alteration. Samples range from being nearly anhydrous to fully altered, essentially representing snapshots of the alteration process through time. We studied oxygen isotopes in secondary-minerals from six CR chondrites of varying hydration states to determine how aqueous fluid conditions (including composition and temperature) evolved on the parent body. Secondary minerals analyzed included calcite, dolomite, and magnetite. The O-isotope composition of calcites ranged from δ18O ≈ 9 to 35‰, dolomites from δ18O ≈ 23 to 27‰, and magnetites from δ18O ≈ -18 to 5‰. Calcite in less-altered samples showed more evidence of fluid evolution compared to heavily altered samples, likely reflecting lower water/rock ratios. Most magnetite plotted on a single trend, with the exception of grains from the extensively hydrated chondrite MIL 090292. The MIL 090292 magnetite diverges from this trend, possibly indicating an anomalous origin for the meteorite. If magnetite and calcite formed in equilibrium, then the relative 18O fractionation between them can be used to extract the temperature of co-precipitation. Isotopic fractionation in Al Rais carbonate-magnetite assemblages revealed low precipitation temperatures (∼60 °C). Assuming that the CR parent body experienced closed-system alteration, a similar exercise for parallel calcite and magnetite O-isotope arrays yields "global" alteration temperatures of ∼55 to 88 °C. These secondary mineral arrays indicate that the O-isotopic composition of the altering fluid evolved upon progressive alteration, beginning near the Al Rais water composition of Δ17O ∼ 1‰ and δ18O ∼ 10‰, and becoming increasingly

  19. Altered insular activation and increased insular functional connectivity during sad and happy face processing in adolescent major depressive disorder.

    Science.gov (United States)

    Henje Blom, Eva; Connolly, Colm G; Ho, Tiffany C; LeWinn, Kaja Z; Mobayed, Nisreen; Han, Laura; Paulus, Martin P; Wu, Jing; Simmons, Alan N; Yang, Tony T

    2015-06-01

    Major depressive disorder (MDD) is a leading cause of disability worldwide and occurs commonly first during adolescence. The insular cortex (IC) plays an important role in integrating emotion processing with interoception and has been implicated recently in the pathophysiology of adult and adolescent MDD. However, no studies have yet specifically examined the IC in adolescent MDD during processing of faces in the sad-happy continuum. Thus, the aim of the present study is to investigate the IC during sad and happy face processing in adolescents with MDD compared to healthy controls (HCL). Thirty-one adolescents (22 female) with MDD and 36 (23 female) HCL underwent a well-validated emotional processing fMRI paradigm that included sad and happy face stimuli. The MDD group showed significantly less differential activation of the anterior/middle insular cortex (AMIC) in response to sad versus happy faces compared to the HCL group. AMIC also showed greater functional connectivity with right fusiform gyrus, left middle frontal gyrus, and right amygdala/parahippocampal gyrus in the MDD compared to HCL group. Moreover, differential activation to sad and happy faces in AMIC correlated negatively with depression severity within the MDD group. Small age-range and cross-sectional nature precluded assessment of development of the AMIC in adolescent depression. Given the role of the IC in integrating bodily stimuli with conscious cognitive and emotional processes, our findings of aberrant AMIC function in adolescent MDD provide a neuroscientific rationale for targeting the AMIC in the development of new treatment modalities. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Uncertainty in visual processes predicts geometrical optical illusions.

    Science.gov (United States)

    Fermüller, Cornelia; Malm, Henrik

    2004-03-01

    It is proposed in this paper that many geometrical optical illusions, as well as illusory patterns due to motion signals in line drawings, are due to the statistics of visual computations. The interpretation of image patterns is preceded by a step where image features such as lines, intersections of lines, or local image movement must be derived. However, there are many sources of noise or uncertainty in the formation and processing of images, and they cause problems in the estimation of these features; in particular, they cause bias. As a result, the locations of features are perceived erroneously and the appearance of the patterns is altered. The bias occurs with any visual processing of line features; under average conditions it is not large enough to be noticeable, but illusory patterns are such that the bias is highly pronounced. Thus, the broader message of this paper is that there is a general uncertainty principle which governs the workings of vision systems, and optical illusions are an artifact of this principle.