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Sample records for understand functional histaminergic

  1. Studies on functional roles of the histaminergic neuron system by using pharmacological agents, knockout mice and positron emission tomography

    International Nuclear Information System (INIS)

    Watanabe, Takehiko; Yanai, Kazuhiko

    2001-01-01

    Since one of us, Takehiko Watanabe (TW), elucidated the location and distribution of the histaminergic neuron system in the brain with antibody raised against L-histidine decarboxylase (a histamine-forming enzyme, HDC) as a marker in 1984 and came to Tohoku University School of Medicine in Sendai, we have been collaborating on the functions of this neuron system by using pharmacological agents, knockout mice of the histamine-related genes, and, in some cases, positron emission tomography (PET). Many of our graduate students and colleagues have been actively involved in histamine research since 1985. Our extensive studies have clarified some of the functions of histamine neurons using methods from molecular techniques to non-invasive human PET imaging. Histamine neurons are involved in many brain functions, such as spontaneous locomotion, arousal in wake-sleep cycle, appetite control, seizures, learning and memory, aggressive behavior and emotion. Particularly, the histaminergic neuron system is one of the most important neuron systems to maintain and stimulate wakefulness. Histamine also functions as a biprotection system against various noxious and unfavorable stimuli (for examples, convulsion, nociception, drug sensitization, ischemic lesions, and stress). Although activators of histamine neurons have not been clinically available until now, we would like to point out that the activation of the histaminergic neuron system is important to maintain mental health. Here, we summarize the newly-discovered functions of histamine neurons mainly on the basis of results from our research groups. (author)

  2. Studies on functional roles of the histaminergic neuron system by using pharmacological agents, knockout mice and positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Takehiko; Yanai, Kazuhiko [Tohoku Univ., Sendai (Japan). Graduate School of Medicine

    2001-12-01

    Since one of us, Takehiko Watanabe (TW), elucidated the location and distribution of the histaminergic neuron system in the brain with antibody raised against L-histidine decarboxylase (a histamine-forming enzyme, HDC) as a marker in 1984 and came to Tohoku University School of Medicine in Sendai, we have been collaborating on the functions of this neuron system by using pharmacological agents, knockout mice of the histamine-related genes, and, in some cases, positron emission tomography (PET). Many of our graduate students and colleagues have been actively involved in histamine research since 1985. Our extensive studies have clarified some of the functions of histamine neurons using methods from molecular techniques to non-invasive human PET imaging. Histamine neurons are involved in many brain functions, such as spontaneous locomotion, arousal in wake-sleep cycle, appetite control, seizures, learning and memory, aggressive behavior and emotion. Particularly, the histaminergic neuron system is one of the most important neuron systems to maintain and stimulate wakefulness. Histamine also functions as a biprotection system against various noxious and unfavorable stimuli (for examples, convulsion, nociception, drug sensitization, ischemic lesions, and stress). Although activators of histamine neurons have not been clinically available until now, we would like to point out that the activation of the histaminergic neuron system is important to maintain mental health. Here, we summarize the newly-discovered functions of histamine neurons mainly on the basis of results from our research groups. (author)

  3. Histaminergic Angioedema.

    Science.gov (United States)

    Busse, Paula J; Smith, Tukisa

    2017-08-01

    Angioedema is frequently categorized into histamine- or bradykinin-mediated disease. It is critical to determine the underlying mediator of symptoms as it directs treatment. Histaminergic angioedema is the most frequent cause of angioedema. It is classified as either acute (lasting 6 weeks). It is further classified into angioedema presenting with or without urticaria. Some patients with acute angioedema may have disease that becomes chronic. Mast cells and basophils are central to the underlying pathophysiology of histamine-mediated angioedema. The underlying treatments of histamine-mediated angioedema are antihistamines, corticosteroids, and epinephrine. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. The human histaminergic system in neuropsychiatric disorders

    NARCIS (Netherlands)

    Shan, Ling; Bao, Ai-Min; Swaab, Dick F

    Histaminergic neurons are exclusively located in the hypothalamic tuberomamillary nucleus, from where they project to many brain areas. The histaminergic system is involved in basic physiological functions, such as the sleep-wake cycle, energy and endocrine homeostasis, sensory and motor functions,

  5. Current Knowledge and Perspectives on Histamine H1 and H2 Receptor Pharmacology: Functional Selectivity, Receptor Crosstalk, and Repositioning of Classic Histaminergic Ligands.

    Science.gov (United States)

    Monczor, Federico; Fernandez, Natalia

    2016-11-01

    H 1 and H 2 histamine receptor antagonists, although developed many decades ago, are still effective for the treatment of allergic and gastric acid-related conditions. This article focuses on novel aspects of the pharmacology and molecular mechanisms of histamine receptors that should be contemplated for optimizing current therapies, repositioning histaminergic ligands for new therapeutic uses, or even including agonists of the histaminergic system in the treatment of different pathologies such as leukemia or neurodegenerative disorders. In recent years, new signaling phenomena related to H 1 and H 2 receptors have been described that make them suitable for novel therapeutic approaches. Crosstalk between histamine receptors and other membrane or nuclear receptors can be envisaged as a way to modulate other signaling pathways and to potentiate the efficacy of drugs acting on different receptors. Likewise, biased signaling at histamine receptors seems to be a pharmacological feature that can be exploited to investigate nontraditional therapeutic uses for H 1 and H 2 biased agonists in malignancies such as acute myeloid leukemia and to avoid undesired side effects when used in standard treatments. It is hoped that the molecular mechanisms discussed in this review contribute to a better understanding of the different aspects involved in histamine receptor pharmacology, which in turn will contribute to increased drug efficacy, avoidance of adverse effects, or repositioning of histaminergic ligands. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

  6. Proton- and ammonium-sensing by histaminergic neurons controlling wakefulness.

    Science.gov (United States)

    Yanovsky, Yevgenij; Zigman, Jeffrey M; Kernder, Anna; Bein, Alisa; Sakata, Ichiro; Osborne-Lawrence, Sherri; Haas, Helmut L; Sergeeva, Olga A

    2012-01-01

    The histaminergic neurons in the tuberomamillary nucleus (TMN) of the posterior hypothalamus are involved in the control of arousal. These neurons are sensitive to hypercapnia as has been shown in experiments examining c-Fos expression, a marker for increased neuronal activity. We investigated the mechanisms through which TMN neurons respond to changes in extracellular levels of acid/CO(2). Recordings in rat brain slices revealed that acidification within the physiological range (pH from 7.4 to 7.0), as well as ammonium chloride (5 mM), excite histaminergic neurons. This excitation is significantly reduced by antagonists of type I metabotropic glutamate receptors and abolished by benzamil, an antagonist of acid-sensing ion channels (ASICs) and Na(+)/Ca(2+) exchanger, or by ouabain which blocks Na(+)/K(+) ATPase. We detected variable combinations of 4 known types of ASICs in single TMN neurons, and observed activation of ASICs in single dissociated TMN neurons only at pH lower than 7.0. Thus, glutamate, which is known to be released by glial cells and orexinergic neurons, amplifies the acid/CO(2)-induced activation of TMN neurons. This amplification demands the coordinated function of metabotropic glutamate receptors, Na(+)/Ca(2+) exchanger and Na(+)/K(+) ATPase. We also developed a novel HDC-Cre transgenic reporter mouse line in which histaminergic TMN neurons can be visualized. In contrast to the rat, the mouse histaminergic neurons lacked the pH 7.0-induced excitation and displayed only a minimal response to the mGluR I agonist DHPG (0.5 μM). On the other hand, ammonium-induced excitation was similar in mouse and rat. These results are relevant for the understanding of the neuronal mechanisms controlling acid/CO(2)-induced arousal in hepatic encephalopathy and obstructive sleep apnoea. Moreover, the new HDC-Cre mouse model will be a useful tool for studying the physiological and pathophysiological roles of the histaminergic system.

  7. Proton- and ammonium- sensing by histaminergic neurons controlling wakefulness.

    Directory of Open Access Journals (Sweden)

    Yvgenij eYanovsky

    2012-04-01

    Full Text Available Orexinergic and histaminergic neurons in the posterior hypothalamus are involved in the control of arousal. Extracellular levels of acid /CO2 are fundamental physicochemical signals controlling wakefulness and breathing. Acidification excites orexinergic neurons like the chemosensory neurons in the brain stem. Hypercapnia induces c-Fos expression, a marker for increased neuronal activity, in the rat histaminergic tuberomamillary nucleus (TMN, but the mechanisms of this excitation are unknown. Acid-sensing ion channels (ASICs are gated by protons and also by ammonium. Recordings in rat brain slices revealed now that acidification within the physiological range (pH from 7.3 to 7.0 as well as ammonium chloride (5mM excite histaminergic neurons. We detected variable combinations of 4 known types of ASICs in single TMN neurons, along with the pharmacological properties of pH-induced current. At pH 7.0 however, activation of ASICs in TMN neurons was negligible. Block of type I metabotropic glutamate receptors abolished proton- but not ammonium- induced excitation. Mouse TMN neurons were identified within a novel HDC-Cre transgenic reporter mouse line. In contrast to the rat these lacked pH 7.0-induced excitation and showed only a minimal response to the mGluR I agonist DHPG (0.5µM. Ammonium-induced excitation was similar in mouse and rat. Thus glutamate, which is released by glial cells and orexinergic axons amplifies CO2/acid-induced arousal through the recruitment of the histaminergic system in rat but not in mouse. These results are relevant for the understanding of neuronal mechanisms controlling H+/CO2-induced arousal in hepatic encephalopathy and obstructive sleep apnoea. The new HDC-Cre mouse model will be a useful tool for studying the physiological and pathophysiological roles of the histaminergic system.

  8. Distribution of histaminergic neuronal cluster in the rat and mouse hypothalamus.

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    Moriwaki, Chinatsu; Chiba, Seiichi; Wei, Huixing; Aosa, Taishi; Kitamura, Hirokazu; Ina, Keisuke; Shibata, Hirotaka; Fujikura, Yoshihisa

    2015-10-01

    Histidine decarboxylase (HDC) catalyzes the biosynthesis of histamine from L-histidine and is expressed throughout the mammalian nervous system by histaminergic neurons. Histaminergic neurons arise in the posterior mesencephalon during the early embryonic period and gradually develop into two histaminergic substreams around the lateral area of the posterior hypothalamus and the more anterior peri-cerebral aqueduct area before finally forming an adult-like pattern comprising five neuronal clusters, E1, E2, E3, E4, and E5, at the postnatal stage. This distribution of histaminergic neuronal clusters in the rat hypothalamus appears to be a consequence of neuronal development and reflects the functional differentiation within each neuronal cluster. However, the close linkage between the locations of histaminergic neuronal clusters and their physiological functions has yet to be fully elucidated because of the sparse information regarding the location and orientation of each histaminergic neuronal clusters in the hypothalamus of rats and mice. To clarify the distribution of the five-histaminergic neuronal clusters more clearly, we performed an immunohistochemical study using the anti-HDC antibody on serial sections of the rat hypothalamus according to the brain maps of rat and mouse. Our results confirmed that the HDC-immunoreactive (HDCi) neuronal clusters in the hypothalamus of rats and mice are observed in the ventrolateral part of the most posterior hypothalamus (E1), ventrolateral part of the posterior hypothalamus (E2), ventromedial part from the medial to the posterior hypothalamus (E3), periventricular part from the anterior to the medial hypothalamus (E4), and diffusely extended part of the more dorsal and almost entire hypothalamus (E5). The stereological estimation of the total number of HDCi neurons of each clusters revealed the larger amount of the rat than the mouse. The characterization of histaminergic neuronal clusters in the hypothalamus of rats and

  9. Human surrogate models of histaminergic and non-histaminergic itch

    DEFF Research Database (Denmark)

    Andersen, Hjalte Holm; Elberling, Jesper; Arendt-Nielsen, Lars

    2015-01-01

    Within the last decade understanding of the mechanistic basis of itch has improved significantly, resulting in the development of several human surrogate models of itch and related dysesthetic states. Well-characterized somatosensory models are useful in basic studies in healthy volunteers...

  10. Central histaminergic transmission modulates the ethanol induced anxiolysis in mice.

    Science.gov (United States)

    Verma, Lokesh; Jain, Nishant S

    2016-10-15

    histaminergic transmission functions to negatively modulate the acute ethanol-induced anxiolysis probably via stimulation of postsynaptic H1 receptor and histamine might contribute to the anxiolytic action of ethanol via H2 receptor activation. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Histaminergic regulation of seasonal metabolic rhythms in Siberian hamsters.

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    I'anson, Helen; Jethwa, Preeti H; Warner, Amy; Ebling, Francis J P

    2011-06-01

    We investigated whether histaminergic tone contributes to the seasonal catabolic state in Siberian hamsters by determining the effect of ablation of histaminergic neurons on food intake, metabolic rate and body weight. A ribosomal toxin (saporin) conjugated to orexin-B was infused into the ventral tuberomammillary region of the hypothalamus, since most histaminergic neurons express orexin receptors. This caused not only 75-80% loss of histaminergic neurons in the posterior hypothalamus, but also some loss of other orexin-receptor expressing cells e.g. MCH neurons. In the long-day anabolic state, lesions produced a transient post-surgical decrease in body weight, but the hamsters recovered and maintained constant body weight, whereas weight gradually increased in sham-lesioned hamsters. VO(2) in the dark phase was significantly higher in the lesioned hamsters compared to shams, and locomotor activity also tended to be higher. In a second study in short days, sham-treated hamsters showed the expected seasonal decrease in body weight, but weight remained constant in the lesioned hamsters, as in the long-day study. Lesioned hamsters consumed more during the early dark phase and less during the light phase due to an increase in the frequency of meals during the dark and decreased meal size during the light, and their cumulative food intake in their home cages was greater than in the control hamsters. In summary, ablation of orexin-responsive cells in the posterior hypothalamus blocks the short-day induced decline in body weight by preventing seasonal hypophagia, evidence consistent with the hypothesis that central histaminergic mechanisms contribute to long-term regulation of body weight. Copyright © 2011 Elsevier Inc. All rights reserved.

  12. Histaminergic ligands injected into the nucleus basalis magnocellularis differentially affect fear conditioning consolidation.

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    Benetti, Fernando; Baldi, Elisabetta; Bucherelli, Corrado; Blandina, Patrizio; Passani, Maria Beatrice

    2013-04-01

    The role of the nucleus basalis magnocellularis (NBM) in fear conditioning encoding is well established. In the present report, we investigate the involvement of the NBM histaminergic system in consolidating fear memories. The NBM was injected bilaterally with ligands of histaminergic receptors immediately after contextual fear conditioning. Histaminergic compounds, either alone or in combination, were stereotaxically administered to different groups of adult male Wistar rats and memory was assessed as conditioned freezing duration 72 h after administration. This protocol prevents interference with NBM function during either acquisition or retrieval phases, hence restricting the effect of pharmacological manipulations to fear memory consolidation. The results presented here demonstrate that post-training H3 receptors (H3R) blockade with the antagonist/inverse agonist thioperamide or activation with immepip in the NBM potentiates or decreases, respectively, freezing response at retrieval. Thioperamide induced memory enhancement seems to depend on H2R, but not H1R activation, as the H2R antagonist zolantidine blocked the effect of thioperamide, whereas the H1R antagonist pyrilamine was ineffective. Furthermore, the H2R agonist ampthamine improved fear memory expression independently of the H3R agonist effect. Our results indicate that activation of post-synaptic H2R within the NBM by endogenous histamine is responsible for the potentiated expression of fear responses. The results are discussed in terms of activation of H3 auto- and heteroreceptors within the NBM and the differential effect of H3R ligands on fear memory consolidation in distinct brain regions.

  13. Blood flow distribution with adrenergic and histaminergic antagonists

    Energy Technology Data Exchange (ETDEWEB)

    Baker, C.H.; Davis, D.L.; Sutton, E.T.

    1989-03-01

    Superficial fibular nerve stimulation (SFNS) causes increased pre- and post-capillary resistances as well as increased capillary permeability in the dog hind paw. These responses indicate possible adrenergic and histaminergic interactions. The distribution of blood flow between capillaries and arteriovenous anastomoses (AVA) may depend on the relative effects of these neural inputs. Right hind paws of anesthetized heparinized dogs were vascularly and neurally isolated and perfused with controlled pressure. Blood flow distribution was calculated from the venous recovery of 85Sr-labeled microspheres (15 microns). The mean transit times of 131I-albumin and 85Sr-labeled microspheres were calculated. The effects of adrenergic and histaminergic antagonists with and without SFNS were determined. Phentolamine blocked the entire response to SFNS. Prazosin attenuated increases in total and AVA resistance. Yohimbine prevented increased total resistance, attenuated the AVA resistance increase, and revealed a decrease in capillary circuit resistance. Pyrilamine attenuated total resistance increase while SFNS increased capillary and AVA resistances. Metiamide had no effect on blood flow distribution with SFNS. The increase in AVA resistance with SFNS apparently resulted from a combination of alpha 1 and alpha 2 receptor stimulation but not histaminergic effects.

  14. Blood flow distribution with adrenergic and histaminergic antagonists

    International Nuclear Information System (INIS)

    Baker, C.H.; Davis, D.L.; Sutton, E.T.

    1989-01-01

    Superficial fibular nerve stimulation (SFNS) causes increased pre- and post-capillary resistances as well as increased capillary permeability in the dog hind paw. These responses indicate possible adrenergic and histaminergic interactions. The distribution of blood flow between capillaries and arteriovenous anastomoses (AVA) may depend on the relative effects of these neural inputs. Right hind paws of anesthetized heparinized dogs were vascularly and neurally isolated and perfused with controlled pressure. Blood flow distribution was calculated from the venous recovery of 85Sr-labeled microspheres (15 microns). The mean transit times of 131I-albumin and 85Sr-labeled microspheres were calculated. The effects of adrenergic and histaminergic antagonists with and without SFNS were determined. Phentolamine blocked the entire response to SFNS. Prazosin attenuated increases in total and AVA resistance. Yohimbine prevented increased total resistance, attenuated the AVA resistance increase, and revealed a decrease in capillary circuit resistance. Pyrilamine attenuated total resistance increase while SFNS increased capillary and AVA resistances. Metiamide had no effect on blood flow distribution with SFNS. The increase in AVA resistance with SFNS apparently resulted from a combination of alpha 1 and alpha 2 receptor stimulation but not histaminergic effects

  15. A Test–Retest Reliability Study of Human Experimental Models of Histaminergic and Non-histaminergic Itch

    DEFF Research Database (Denmark)

    Andersen, Hjalte H.; Sørensen, Anne Kathrine R.; Nielsen, Gebbie A.R.

    2017-01-01

    Numerous exploratory, proof-of-concept and interventional studies have used histaminergic and non-histaminergic human models of itch. However, no reliability studies for such surrogate models have been conducted. This study investigated the test–retest reliability for the response to histamine.......57– 0.77, CVbetween =97%, CVwithin =41%) and histamine: (ICC=0.83–0.93, CVbetween =97%, CVwithin =20%) exhibited moderate-to-excellent intra-individual reliability and moderate inter-individual reliability for the itch intensity. For a test–retest observation period of one week, SPT-delivered histamine......- and cowhage- (5, 15, 25 spiculae) induced itch in healthy volunteers. Cowhage spiculae were individually applied with tweezers and 1% histamine was applied with a skin prick test (SPT) lancet, both on the volar forearm. The intensity of itch was recorded on a visual analogue scale and self-reported area...

  16. Histaminergic activity in a rodent model of Parkinson's disease.

    Science.gov (United States)

    Nowak, Przemysław; Noras, Lukasz; Jochem, Jerzy; Szkilnik, Ryszard; Brus, Halina; Körossy, Eva; Drab, Jacek; Kostrzewa, Richard M; Brus, Ryszard

    2009-04-01

    Rats lesioned shortly after birth with 6-OHDA have been proposed to be a near-ideal model of severe Parkinson's disease, because of non-lethality of the procedure, near-total destruction of nigrostriatal dopaminergic fibers, and near-total dopamine (DA) denervation of striatum. There are scarce data that in Parkinson's disease, activity of the central histaminergic system is increased. Therefore, the aim of this study was to determine histamine content in the brain and the effect of histamine receptor antagonists on behavior of adult rats. At 3 days after birth, Wistar rats were pretreated with desipramine (20.0 mg/kg ip) 1 h before bilateral icv administration of the catecholaminergic neurotoxin 6-OHDA (67 microg base, on each side) or saline-ascorbic acid (0.1%) vehicle (control). At 8 weeks levels of DA and its metabolites L: -3,4-dihydroxyphenylalanine (DOPAC) and homovanillic acid (HVA) were estimated in the striatum and frontal cortex by HPCL/ED technique. In the hypothalamus, hippocampus, frontal cortex, and medulla oblongata, the level of histamine was analyzed by immunoenzymatic method. Behavioral observations (locomotion, exploratory-, oral-, and stereotyped-activity) were additionally made on control and 6-OHDA neonatally lesioned rats. Effects of DA receptor agonists (SKF 38393, apomorphine) and histamine receptor antagonists (e.g., S(+)chlorpheniramine, H(1); cimetidine, H(2); thioperamide, H(3) agonist) were determined. We confirmed that 6-OHDA significantly reduced contents of DA and its metabolites in the brain in adulthood. Histamine content was significantly increased in the hypothalamus, hipocampus, and medulla oblongata. Moreover, in 6-OHDA-lesioned rats behavioral response was altered mainly by thioperamide (H(3) antagonist). These findings indicate that histamine and the central histaminergic system are altered in the brain of rats lesioned to model Parkinson's disease, and that histaminergic neurons exert a modulating role in Parkinsonian 6

  17. Pharmacological effects of carcinine on histaminergic neurons in the brain

    OpenAIRE

    Chen, Zhong; Sakurai, Eiko; Hu, Weiwei; Jin, Chunlei; Kiso, Yoshinobu; Kato, Motohisa; Watanabe, Takehiko; Wei, Erqing; Yanai, Kazuhiko

    2004-01-01

    Carcinine (β-alanyl histamine) is an imidazole dipeptide. The present study was designed to characterize the pharmacological effects of carcinine on histaminergic activity in the brain and on certain neurobehavior.Carcinine was highly selective for the histamine H3 receptor over H1 or H2 receptor (Ki (μM)=0.2939±0.2188 vs 3621.2±583.9 or 365.3±232.8 μM, respectively).Carcinine at a dose of 20 mg kg−1 slightly increased histidine decarboxylase (HDC) activity in the cortex (from 0.186±0.069 to ...

  18. Novel insights into the echinoderm nervous system from histaminergic and FMRFaminergic-like cells in the sea cucumber Leptosynapta clarki.

    Science.gov (United States)

    Hoekstra, Luke A; Moroz, Leonid L; Heyland, Andreas

    2012-01-01

    Understanding of the echinoderm nervous system is limited due to its distinct organization in comparison to other animal phyla and by the difficulty in accessing it. The transparent and accessible, apodid sea cucumber Leptosynapta clarki provides novel opportunities for detailed characterization of echinoderm neural systems. The present study used immunohistochemistry against FMRFamide and histamine to describe the neural organization in juvenile and adult sea cucumbers. Histaminergic- and FMRFaminergic-like immunoreactivity is reported in several distinct cell types throughout the body of L. clarki. FMRFamide-like immunoreactive cell bodies were found in the buccal tentacles, esophageal region and in proximity to the radial nerve cords. Sensory-like cells in the tentacles send processes toward the circumoral nerve ring, while unipolar and bipolar cells close to the radial nerve cords display extensive processes in close association with muscle and other cells of the body wall. Histamine-like immunoreactivity was identified in neuronal somatas located in the buccal tentacles, circumoral nerve ring and in papillae distributed across the body. The tentacular cells send processes into the nerve ring, while the processes of cells in the body wall papillae extend to the surface epithelium and radial nerve cords. Pharmacological application of histamine produced a strong coordinated, peristaltic response of the body wall suggesting the role of histamine in the feeding behavior. Our immunohistochemical data provide evidence for extensive connections between the hyponeural and ectoneural nervous system in the sea cucumber, challenging previously held views on a clear functional separation of the sub-components of the nervous system. Furthermore, our data indicate a potential function of histamine in coordinated, peristaltic movements; consistent with feeding patterns in this species. This study on L. clarki illustrates how using a broader range of neurotransmitter systems

  19. Novel insights into the echinoderm nervous system from histaminergic and FMRFaminergic-like cells in the sea cucumber Leptosynapta clarki.

    Directory of Open Access Journals (Sweden)

    Luke A Hoekstra

    Full Text Available Understanding of the echinoderm nervous system is limited due to its distinct organization in comparison to other animal phyla and by the difficulty in accessing it. The transparent and accessible, apodid sea cucumber Leptosynapta clarki provides novel opportunities for detailed characterization of echinoderm neural systems. The present study used immunohistochemistry against FMRFamide and histamine to describe the neural organization in juvenile and adult sea cucumbers. Histaminergic- and FMRFaminergic-like immunoreactivity is reported in several distinct cell types throughout the body of L. clarki. FMRFamide-like immunoreactive cell bodies were found in the buccal tentacles, esophageal region and in proximity to the radial nerve cords. Sensory-like cells in the tentacles send processes toward the circumoral nerve ring, while unipolar and bipolar cells close to the radial nerve cords display extensive processes in close association with muscle and other cells of the body wall. Histamine-like immunoreactivity was identified in neuronal somatas located in the buccal tentacles, circumoral nerve ring and in papillae distributed across the body. The tentacular cells send processes into the nerve ring, while the processes of cells in the body wall papillae extend to the surface epithelium and radial nerve cords. Pharmacological application of histamine produced a strong coordinated, peristaltic response of the body wall suggesting the role of histamine in the feeding behavior. Our immunohistochemical data provide evidence for extensive connections between the hyponeural and ectoneural nervous system in the sea cucumber, challenging previously held views on a clear functional separation of the sub-components of the nervous system. Furthermore, our data indicate a potential function of histamine in coordinated, peristaltic movements; consistent with feeding patterns in this species. This study on L. clarki illustrates how using a broader range of

  20. Interactions of the orexin/hypocretin neurones and the histaminergic system.

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    Sundvik, M; Panula, P

    2015-02-01

    Histaminergic and orexin/hypocretin systems are components in the brain wake-promoting system. Both are affected in the sleep disorder narcolepsy, but the role of histamine in narcolepsy is unclear. The histaminergic neurones are activated by the orexin/hypocretin system in rodents, and the development of the orexin/hypocretin neurones is bidirectionally regulated by the histaminergic system in zebrafish. This review summarizes the current knowledge of the interactions of these two systems in normal and pathological conditions in humans and different animal models. © 2014 Scandinavian Physiological Society. Published by John Wiley & Sons Ltd.

  1. Possible involvement of serotonin 5-HT2 receptor in the regulation of feeding behavior through the histaminergic system.

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    Murotani, Tomotaka; Ishizuka, Tomoko; Isogawa, Yuka; Karashima, Michitaka; Yamatodani, Atsushi

    2011-01-01

    The central histaminergic system has been proven to be involved in several physiological functions including feeding behavior. Some atypical antipsychotics like risperidone and aripiprazole are known to affect feeding behavior and to antagonize the serotonin (5-HT) receptor subtypes. To examine the possible neural relationship between the serotonergic and histaminergic systems in the anorectic effect of the antipsychotics, we studied the effect of a single administration of these drugs on food intake and hypothalamic histamine release in mice using in vivo microdialysis. Single injection of risperidone (0.5mg/kg, i.p.) or aripiprazole (1mg/kg, i.p.), which have binding affinities to 5-HT(1A, 2A, 2B) and (2C) receptors decreased food intake in C57BL/6N mice with concomitant increase of hypothalamic histamine release. However, a selective D(2)-antagonist, haloperidol (0.5mg/kg, i.p.), did not have effects on food intake or histamine release. Furthermore, in histamine H(1) receptor-deficient mice, there was no reduction of food intake induced by atypical antipsychotics, although histamine release was increased. Moreover, selective 5-HT(2A)-antagonists, volinanserin (0.5, 1mg/kg, i.p.) and ketanserin (5, 10mg/kg, i.p.), significantly increased histamine release and 5-HT(2B/2C) -antagonist, SB206553 (2.5, 5mg/kg, i.p.), slightly increased it. On the contrary, 5-HT(1A) -selective antagonist, WAY100635 (1, 2mg/kg), did not affect the histaminergic tone. These findings suggest that serotonin tonically inhibits histamine release via 5-HT(2) receptors and that antipsychotics enhance the release of hypothalamic histamine by blockade of 5-HT(2) receptors resulting in anorexia via the H(1) receptor. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Histaminergic modulation of cholinergic release from the nucleus basalis magnocellularis into insular cortex during taste aversive memory formation.

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    Liliana Purón-Sierra

    Full Text Available The ability of acetylcholine (ACh to alter specific functional properties of the cortex endows the cholinergic system with an important modulatory role in memory formation. For example, an increase in ACh release occurs during novel stimulus processing, indicating that ACh activity is critical during early stages of memory processing. During novel taste presentation, there is an increase in ACh release in the insular cortex (IC, a major structure for taste memory recognition. There is extensive evidence implicating the cholinergic efferents of the nucleus basalis magnocellularis (NBM in cortical activity changes during learning processes, and new evidence suggests that the histaminergic system may interact with the cholinergic system in important ways. However, there is little information as to whether changes in cholinergic activity in the IC are modulated during taste memory formation. Therefore, in the present study, we evaluated the influence of two histamine receptor subtypes, H1 in the NBM and H3 in the IC, on ACh release in the IC during conditioned taste aversion (CTA. Injection of the H3 receptor agonist R-α-methylhistamine (RAMH into the IC or of the H1 receptor antagonist pyrilamine into the NBM during CTA training impaired subsequent CTA memory, and simultaneously resulted in a reduction of ACh release in the IC. This study demonstrated that basal and cortical cholinergic pathways are finely tuned by histaminergic activity during CTA, since dual actions of histamine receptor subtypes on ACh modulation release each have a significant impact during taste memory formation.

  3. Inhibition of histaminergic receptors in rat jejunum by Indacrinone

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    Kadkhodaee M

    1999-08-01

    Full Text Available Indacrinone is a loop diuretic which also has uricosuric, kaliuretic, saliuretic and natriuretic effects. Since it has been reported that this drug has several actions in different organs, we decided to evaluate its mechanism of action on the rat jejunum smooth muscle. After preparation of the tissues, different concentrations of indacrinone were applied. Doses of 8.2×10^-6 M, 2.7×10^-5 M, 8.2×10^-5 M and 2.7×10^-4 M were all effective in a dose dependent manner to relax the muscle. Increase in the drug concentration resulted in much faster reduction in twitch amplitude. The jejunum is innervated by adernergic, cholinergic, serotonergic and histaminergic systems. To find the mechanism of action of indacrinone in rat jejunum, experiments were conducted by appropriate receptor agonists and antagonists of the above systems. There was a marked increase in muscle contraction tone and ampliture by the use of histamine, while indacrinone prevented the increase induced by histamine. It was concluded that indacrinone may be a competitive antagonist for histamin receptors in rat jejunum muscle.

  4. Histaminergic system in brain disorders: lessons from the translational approach and future perspectives.

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    Baronio, Diego; Gonchoroski, Taylor; Castro, Kamila; Zanatta, Geancarlo; Gottfried, Carmem; Riesgo, Rudimar

    2014-01-01

    Histamine and its receptors were first described as part of immune and gastrointestinal systems, but their presence in the central nervous system and importance in behavior are gaining more attention. The histaminergic system modulates different processes including wakefulness, feeding, and learning and memory consolidation. Histamine receptors (H1R, H2R, H3R, and H4R) belong to the rhodopsin-like family of G protein-coupled receptors, present constitutive activity, and are subjected to inverse agonist action. The involvement of the histaminergic system in brain disorders, such as Alzheimer's disease, schizophrenia, sleep disorders, drug dependence, and Parkinson's disease, is largely studied. Data obtained from preclinical studies point antagonists of histamine receptors as promising alternatives to treat brain disorders. Thus, clinical trials are currently ongoing to assess the effects of these drugs on humans. This review summarizes the role of histaminergic system in brain disorders, as well as the effects of different histamine antagonists on animal models and humans.

  5. The Histaminergic Tuberomamillary Nucleus Is Involved in Appetite for Sex, Water and Amphetamine.

    Directory of Open Access Journals (Sweden)

    Marco Contreras

    Full Text Available The histaminergic system is one component of the ascending arousal system which is involved in wakefulness, neuroendocrine control, cognition, psychiatric disorders and motivation. During the appetitive phase of motivated behaviors the arousal state rises to an optimal level, thus giving proper intensity to the behavior. Previous studies have demonstrated that the histaminergic neurons show an earlier activation during the appetitive phase of feeding, compared to other ascending arousal system nuclei, paralleled with a high increase in arousal state. Lesions restricted to the histaminergic neurons in rats reduced their motivation to get food even after 24 h of food deprivation, compared with intact or sham lesioned rats. Taken together, these findings indicate that the histaminergic system is important for appetitive behavior related to feeding. However, its role in other goal-directed behaviors remains unexplored. In the present work, male rats rendered motivated to obtain water, sex, or amphetamine showed an increase in Fos-ir of histaminergic neurons in appetitive behaviors directed to get those reinforcers. However, during appetitive tests to obtain sex, or drug in amphetamine-conditioned rats, Fos expression increased in most other ascending arousal system nuclei, including the orexin neurons in the lateral hypothalamus, dorsal raphe, locus coeruleus and laterodorsal tegmental neurons, but not in the ventral tegmental area, which showed no Fos-ir increase in any of the 3 conditions. Importantly, all these appetitive behaviors were drastically reduced after histaminergic cell-specific lesion, suggesting a critical contribution of histamine on the intensity component of several appetitive behaviors.

  6. Histaminergic Neurotransmission as a Gateway for the Cognitive Effect of Oleoylethanolamide in Contextual Fear Conditioning.

    Science.gov (United States)

    Provensi, Gustavo; Fabbri, Roberta; Munari, Leonardo; Costa, Alessia; Baldi, Elisabetta; Bucherelli, Corrado; Blandina, Patrizio; Passani, Maria Beatrice

    2017-05-01

    The integrity of the brain histaminergic system is necessary for the unfolding of homeostatic and cognitive processes through the recruitment of alternative circuits with distinct temporal patterns. We recently demonstrated that the fat-sensing lipid mediator oleoylethanolamide indirectly activates histaminergic neurons to exerts its hypophagic effects. The present experiments investigated whether histaminergic neurotransmission is necessary also for the modulation of emotional memory induced by oleoylethanolamide in a contextual fear conditioning paradigm. We examined the acute effect of i.p. administration of oleoylethanolamide immediately posttraining in the contextual fear conditioning test. Retention test was performed 72 hours after training. To test the participation of the brain histaminergic system in the cognitive effect of oleoylethanolamide, we depleted rats of brain histamine with an i.c.v. injection of alpha-fluoromethylhistidine (a suicide inhibitor of histidine decarboxylase) or bilateral intra-amygdala infusions of histamine H1 or H2 receptor antagonists. We also examined the effect of oleoylethanolamide on histamine release in the amygdala using in vivo microdialysis. Posttraining administration of oleoylethanolamide enhanced freezing time at retention. This effect was blocked by both i.c.v. infusions of alpha-fluoromethylhistidine or by intra-amygdala infusions of either pyrilamine or zolantidine (H1 and H2 receptor antagonists, respectively). Microdialysis experiments showed that oleoylethanolamide increased histamine release from the amygdala of freely moving rats. Our results suggest that activation of the histaminergic system in the amygdala has a "permissive" role on the memory-enhancing effects of oleoylethanolamide. Hence, targeting the H1 and H2 receptors may modify the expression of emotional memory and reduce dysfunctional aversive memories as found in phobias and posttraumatic stress disorder. © The Author 2017. Published by Oxford

  7. Involvement of histaminergic inputs in the jaw-closing reflex arc

    Science.gov (United States)

    Gemba, Chikako; Nakayama, Kiyomi; Nakamura, Shiro; Mochizuki, Ayako; Inoue, Tomio

    2015-01-01

    Histamine receptors are densely expressed in the mesencephalic trigeminal nucleus (MesV) and trigeminal motor nucleus. However, little is known about the functional roles of neuronal histamine in controlling oral-motor activity. Thus, using the whole-cell recording technique in brainstem slice preparations from Wistar rats aged between postnatal days 7 and 13, we investigated the effects of histamine on the MesV neurons innervating the masseter muscle spindles and masseter motoneurons (MMNs) that form a reflex arc for the jaw-closing reflex. Bath application of histamine (100 μM) induced membrane depolarization in both MesV neurons and MMNs in the presence of tetrodotoxin, whereas histamine decreased and increased the input resistance in MesV neurons and MMNs, respectively. The effects of histamine on MesV neurons and MMNs were mimicked by an H1 receptor agonist, 2-pyridylethylamine (100 μM). The effects of an H2 receptor agonist, dimaprit (100 μM), on MesV neurons were inconsistent, whereas MMNs were depolarized without changes in the input resistance. An H3 receptor agonist, immethridine (100 μM), also depolarized both MesV neurons and MMNs without changing the input resistance. Histamine reduced the peak amplitude of postsynaptic currents (PSCs) in MMNs evoked by stimulation of the trigeminal motor nerve (5N), which was mimicked by 2-pyridylethylamine but not by dimaprit or immethridine. Moreover, 2-pyridylethylamine increased the failure rate of PSCs evoked by minimal stimulation and the paired-pulse ratio. These results suggest that histaminergic inputs to MesV neurons through H1 receptors are involved in the suppression of the jaw-closing reflex although histamine depolarizes MesV neurons and/or MMNs. PMID:25904711

  8. Understanding the Executive Functioning Heterogeneity in Schizophrenia

    Science.gov (United States)

    Raffard, Stephane; Bayard, Sophie

    2012-01-01

    Schizophrenia is characterized by heterogeneous brain abnormalities involving cerebral regions implied in the executive functioning. The dysexecutive syndrome is one of the most prominent and functionally cognitive features of schizophrenia. Nevertheless, it is not clear to what extend executive deficits are heterogeneous in schizophrenia…

  9. Understanding Linear Functions and Their Representations

    Science.gov (United States)

    Wells, Pamela J.

    2015-01-01

    Linear functions are an important part of the middle school mathematics curriculum. Students in the middle grades gain fluency by working with linear functions in a variety of representations (NCTM 2001). Presented in this article is an activity that was used with five eighth-grade classes at three different schools. The activity contains 15 cards…

  10. Understanding Microbial Communities: Function, Structure and Dynamics

    Science.gov (United States)

    2015-02-11

    microbial communities: Function, structure and dynamics’, at the Isaac Newton Institute, University of Cambridge, United Kingdom, from August to...dynamics’, at the Isaac Newton Institute, University of Cambridge, United Kingdom, from August to December 2014. The programme involved over 150...Communities: Function, Structure and Dynamics’, at the Isaac Newton Institute, Cambridge University, UK, from 19th August 2014 – 19th December 2014

  11. Idiopathic Non-histaminergic Angioedema: Successful Treatment with Omalizumab in Five Patients.

    Science.gov (United States)

    Faisant, Charles; Du Thanh, Aurélie; Mansard, Catherine; Deroux, Alban; Boccon-Gibod, Isabelle; Bouillet, Laurence

    2017-01-01

    Idiopathic non-histaminergic acquired angioedema (InH-AAE) is a rare disease characterized by AE resistant to antihistamines and a chronic course. We report five new cases of InH-AAE (two women and three men) with a rapid and dramatic response to the anti-immunoglobulin-E antibody omalizumab. In our literature review, we found 13 other relevant cases with a good response to this treatment. Overall, in 6 out of 18 patients, the doses of omalizumab required to prevent recurrences of attacks were higher than the licensed dose for chronic urticaria. No significant adverse effects have been reported.

  12. Effect of the histaminergic antagonist over the pulmonary oedema growth in P. berghei - infected mice

    International Nuclear Information System (INIS)

    Martins, M.A.

    1985-01-01

    The involvement of histaminergic mechanisms in the pathogenesis of pulmonary oedema observed in p. berghei - infected mice was investigated. Histamine concentrations in plasma and whole blood of infected and normal mice were determined by radioenzymatic assay during the seven days of the infection. Elevated plasma and whole blood histamine levels were found at the last stages of infection (sixth day and seventh day) after intraperitoneal injection of parasitized erythrocytes, showing a close temporal correlation between the development of the oedema and the elevation of the circulating histamine concentrations. The participation of H 1 and H 2 receptors in the increase in vascular permeability (IVP) induced by histamine was also verified. (author)

  13. Tranexamic acid as maintenance treatment for non-histaminergic angioedema: analysis of efficacy and safety in 37 patients

    Science.gov (United States)

    Wintenberger, C; Boccon-Gibod, I; Launay, D; Fain, O; Kanny, G; Jeandel, P Y; Martin, L; Gompel, A; Bouillet, L

    2014-01-01

    Angioedema (AE) is a clinical syndrome characterized by localised swelling lasting several hours. The swelling is often recurring and can be lethal if it is located in the laryngeal region. Much progress has been made recently in the treatment of acute episodes, but no consensus has been reached on maintenance treatment. We have performed a national retrospective observational study to assess the use of tranexamic acid (TA) as maintenance treatment for non-histaminergic AE [hereditary AE (HAE) or idiopathic non-histaminergic AE]. Records for 64 cases were collected from 1 October 2012 to 31 August 2013; 37 of these were included (12 HAE with C1-inhibitor deficiency, six with HAE with normal C1-inhibitor and 19 idiopathic non-histaminergic AE). When treated with TA over six months, the number of attacks was reduced by 75% in 17 patients, 10 patients showed a lower level of reduction and 10 had the same number of attacks. In no instances were symptoms increased. No thromboembolic events were observed, and the main side effects were digestive in nature. Thus, TA, which is well tolerated and inexpensive, appears to be an effective maintenance treatment for some patients with HAE or idiopathic non-histaminergic AE. PMID:24827773

  14. Monoaminergic and Histaminergic Strategies and Treatments in Brain Diseases

    Science.gov (United States)

    Di Giovanni, Giuseppe; Svob Strac, Dubravka; Sole, Montse; Unzeta, Mercedes; Tipton, Keith F.; Mück-Šeler, Dorotea; Bolea, Irene; Della Corte, Laura; Nikolac Perkovic, Matea; Pivac, Nela; Smolders, Ilse J.; Stasiak, Anna; Fogel, Wieslawa A.; De Deurwaerdère, Philippe

    2016-01-01

    The monoaminergic systems are the target of several drugs for the treatment of mood, motor and cognitive disorders as well as neurological conditions. In most cases, advances have occurred through serendipity, except for Parkinson's disease where the pathophysiology led almost immediately to the introduction of dopamine restoring agents. Extensive neuropharmacological studies first showed that the primary target of antipsychotics, antidepressants, and anxiolytic drugs were specific components of the monoaminergic systems. Later, some dramatic side effects associated with older medicines were shown to disappear with new chemical compounds targeting the origin of the therapeutic benefit more specifically. The increased knowledge regarding the function and interaction of the monoaminergic systems in the brain resulting from in vivo neurochemical and neurophysiological studies indicated new monoaminergic targets that could achieve the efficacy of the older medicines with fewer side-effects. Yet, this accumulated knowledge regarding monoamines did not produce valuable strategies for diseases where no monoaminergic drug has been shown to be effective. Here, we emphasize the new therapeutic and monoaminergic-based strategies for the treatment of psychiatric diseases. We will consider three main groups of diseases, based on the evidence of monoamines involvement (schizophrenia, depression, obesity), the identification of monoamines in the diseases processes (Parkinson's disease, addiction) and the prospect of the involvement of monoaminergic mechanisms (epilepsy, Alzheimer's disease, stroke). In most cases, the clinically available monoaminergic drugs induce widespread modifications of amine tone or excitability through neurobiological networks and exemplify the overlap between therapeutic approaches to psychiatric and neurological conditions. More recent developments that have resulted in improved drug specificity and responses will be discussed in this review. PMID

  15. Idiopathic histaminergic angioedema without wheals: a case series of 31 patients

    Science.gov (United States)

    Boccon‐Gibod, I.; Mansard, C.; Dumestre Perard, C.; Pralong, P.; Chatain, C.; Deroux, A.; Bouillet, L.

    2016-01-01

    Summary Idiopathic histaminergic acquired angioedema (IH‐AAE) is a common cause of recurrent angioedema without wheals. It is a mast cell‐mediated disease thought to belong to the same clinical entity as chronic urticaria (CU). The objective of this study was to describe the clinical and epidemiological characteristics of IH‐AAE patients. From 2014 to 2015, 534 patients were seen at our national reference centre for angioedema and/or urticaria. Among them, we identified 31 patients with idiopathic histaminergic acquired angioedema without wheals (IH‐AAE). Thirty‐one patients (15 men and 16 women) with a mean age of 50 years met the criteria for IH‐AAE. The average delay in diagnosis was 6·3 years. A history of allergy was found in 12 patients (38·7%), nine suffering from allergic rhinitis. The mean duration of attacks was 28·1 h. The AE attack was located in the upper respiratory tract in 54·8% of cases (17 patients). A lingual location was found in 29% of patients. Men were more likely than women to have an upper airway involvement. No intubations or admissions to intensive care units were reported. The dosage of anti‐histamines to control the symptoms was onefold the recommended dose in 51·6% of patients (16 patients), twofold in 32% (10 patients) and three–fourfold in 16·1% (five patients). IH‐AAE is characterized by an important delay in diagnosis, a frequent involvement of the upper airway and a benign course during attacks. As in CU, a trial of up to fourfold dose of H1‐anti‐histamines may be necessary to control symptoms. PMID:26969870

  16. Idiopathic histaminergic angioedema without wheals: a case series of 31 patients.

    Science.gov (United States)

    Faisant, C; Boccon-Gibod, I; Mansard, C; Dumestre Perard, C; Pralong, P; Chatain, C; Deroux, A; Bouillet, L

    2016-07-01

    Idiopathic histaminergic acquired angioedema (IH-AAE) is a common cause of recurrent angioedema without wheals. It is a mast cell-mediated disease thought to belong to the same clinical entity as chronic urticaria (CU). The objective of this study was to describe the clinical and epidemiological characteristics of IH-AAE patients. From 2014 to 2015, 534 patients were seen at our national reference centre for angioedema and/or urticaria. Among them, we identified 31 patients with idiopathic histaminergic acquired angioedema without wheals (IH-AAE). Thirty-one patients (15 men and 16 women) with a mean age of 50 years met the criteria for IH-AAE. The average delay in diagnosis was 6·3 years. A history of allergy was found in 12 patients (38·7%), nine suffering from allergic rhinitis. The mean duration of attacks was 28·1 h. The AE attack was located in the upper respiratory tract in 54·8% of cases (17 patients). A lingual location was found in 29% of patients. Men were more likely than women to have an upper airway involvement. No intubations or admissions to intensive care units were reported. The dosage of anti-histamines to control the symptoms was onefold the recommended dose in 51·6% of patients (16 patients), twofold in 32% (10 patients) and three-fourfold in 16·1% (five patients). IH-AAE is characterized by an important delay in diagnosis, a frequent involvement of the upper airway and a benign course during attacks. As in CU, a trial of up to fourfold dose of H1-anti-histamines may be necessary to control symptoms. © 2016 British Society for Immunology.

  17. Understanding Control Function and Failure From a Process Perspective

    DEFF Research Database (Denmark)

    Heussen, Kai; Lind, Morten

    2012-01-01

    In control design, fault-identification and fault tolerant control, the controlled process is usually perceived as a dynamical process, captured in a mathematical model. The design of a control system for a complex process, however, begins typically long before these mathematical models become...... relevant and available. To consider the role of control functions in process design, a good qualitative understanding of the process as well as of control functions is required. As the purpose of a control function is closely tied to the process functions, its failure has a direct effects on the process...... behaviour and its function. This paper presents a formal methodology for the qualitative representation of control functions in relation to their process context. Different types of relevant process and control abstractions are introduced and their application to formal analysis of control failure modes...

  18. Understanding schizoaffective disorder: from psychobiology to psychosocial functioning.

    Science.gov (United States)

    Correll, Christoph U

    2010-01-01

    Psychobiologic evidence and psychosocial functioning in patients with schizoaffective disorder suggest that the disease may be a distinct disorder, a variant of schizophrenia or affective disorders, the comorbidity of schizophrenia and a mood disorder, or an intermediate disorder on a spectrum that ranges from schizophrenia to mood disorders. These data, although inconclusive, contribute to clinicians' understanding of the etiology of the disorder. Further research may lead to an increased understanding of the disorder, improved treatment, and, ultimately, better outcomes. © Copyright 2010 Physicians Postgraduate Press, Inc.

  19. Using functional genetics to understand breast cancer biology.

    Science.gov (United States)

    Ashworth, Alan; Bernards, Rene

    2010-07-01

    Genetic screens were for long the prerogative of those that studied model organisms. The discovery in 2001 that gene silencing through RNA interference (RNAi) can also be brought about in mammalian cells paved the way for large scale loss-of-function genetic screens in higher organisms. In this article, we describe how functional genetic studies can help us understand the biology of breast cancer, how it can be used to identify novel targets for breast cancer therapy, and how it can help in the identification of those patients that are most likely to respond to a given therapy.

  20. Histaminergic signaling in the central nervous system of Daphnia and a role for it in the control of phototactic behavior

    Science.gov (United States)

    McCoole, Matthew D.; Baer, Kevin N.; Christie, Andrew E.

    2011-01-01

    SUMMARY Daphnia magna and Daphnia pulex are well-established model organisms in the fields of ecotoxicology and toxicogenomics. Among the many assays used for determining the effects of environmental and anthropogenic stressors on these animals is monitoring for changes in their phototactic behavior. In most arthropods, histamine has been shown to play a key role in the visual system. Currently, nothing is known about histaminergic signaling in either D. magna or D. pulex. Here, a combination of immunohistochemistry and genome mining was used to identify and characterize the histaminergic systems in these daphnids. In addition, a behavioral assay was used to assess the role of histamine in their phototactic response to ultraviolet (UV) light exposure. An extensive network of histaminergic somata, axons and neuropil was identified via immunohistochemistry within the central nervous system of both daphnids, including labeling of putative photoreceptors in the compound eye and projections from these cells to the brain. Mining of the D. pulex genome using known Drosophila melanogaster proteins identified a putative ortholog of histidine decarboxylase (the rate-limiting biosynthetic enzyme for histamine), as well as two putative histamine-gated chloride channels (hclA and hclB orthologs). Exposure of D. magna to cimetidine, an H2 receptor antagonist known to block both hclA and hclB in D. melanogaster, inhibited their negative phototactic response to UV exposure in a reversible, time-dependent manner. Taken collectively, our results show that an extensive histaminergic system is present in Daphnia species, including the visual system, and that this amine is involved in the control of phototaxis in these animals. PMID:21525325

  1. Influence of Adalimumab on the Expression Profile of Genes Associated with the Histaminergic System in the Skin Fibroblasts In Vitro

    Science.gov (United States)

    Grabarek, Beniamin; Zmarzły, Nikola; Skubis, Aleksandra; Kruszniewska-Rajs, Celina; Gola, Joanna; Kucharz, Eugeniusz

    2018-01-01

    Objective The aim of this study was to evaluate the influence of adalimumab on expression profile of genes associated with the histaminergic system in Normal Human Dermal Fibroblast (NHDF) cells stimulated with 8.00 μg/ml of adalimumab and the identification of miRNAs regulating these genes' expression. Methods NHDFs were cultured with or without the presence of adalimumab for 2, 8, and 24 hours. The expression profile of genes and miRNA were determined with the use of microarray technology. Results Among 22283 ID mRNA, 65 are associated with the histaminergic system. It can be observed that 15 mRNAs differentiate NHDFs cultures with adalimumab form control. The analysis of miRNAs showed that, among 1105 ID miRNA, 20 miRNAs are differentiating in cells treated with adalimumab for 2 hours, 9 miRNA after 8 hours, and only 3 miRNAs after 24 hours. Conclusion It was also determined that miRNAs play certain role in the regulation of the expression of genes associated with the histaminergic system. The results of this study confirmed the possibility of using both genes associated with this system as well as miRNAs regulating their expression, as complementary molecular markers of sensitivity to the adalimumab treatment. PMID:29487864

  2. Understanding emergent functions in self-assembled fibrous networks

    Science.gov (United States)

    Sinko, Robert; Keten, Sinan

    2015-09-01

    Understanding self-assembly processes of nanoscale building blocks and characterizing their properties are both imperative for designing new hierarchical, network materials for a wide range of structural, optoelectrical, and transport applications. Although the characterization and choices of these material building blocks have been well studied, our understanding of how to precisely program a specific morphology through self-assembly still must be significantly advanced. In the recent study by Xie et al (2015 Nanotechnology 26 205602), the self-assembly of end-functionalized nanofibres is investigated using a coarse-grained molecular model and offers fundamental insight into how to control the structural morphology of nanofibrous networks. Varying nanoscale networks are observed when the molecular interaction strength is changed and the findings suggest that self-assembly through the tuning of molecular interactions is a key strategy for designing nanostructured networks with specific topologies.

  3. Understanding the Structural Basis of Adhesion GPCR Functions.

    Science.gov (United States)

    Araç, Demet; Sträter, Norbert; Seiradake, Elena

    2016-01-01

    Unlike conventional G-protein-coupled receptors (GPCRs), adhesion GPCRs (aGPCRs) have large extracellular regions that are autoproteolytically cleaved from their membrane-embedded seven-pass transmembrane helices. Autoproteolysis occurs within the conserved GPCR-Autoproteolysis INducing (GAIN) domain that is juxtaposed to the transmembrane domain and cleaves the last beta strand of the GAIN domain. The other domains of the extracellular region are variable and specific to each aGPCR and are likely involved in adhering to various ligands. Emerging evidence suggest that extracellular regions may modulate receptor function and that ligand binding to the extracellular regions may induce receptor activation via multiple mechanisms. Here, we summarize current knowledge about the structural understanding for the extracellular regions of aGPCRs and discuss their possible functional roles that emerge from the available structural information.

  4. Dehydration-induced release of vasopressin involves activation of hypothalamic histaminergic neurons.

    Science.gov (United States)

    Kjaer, A; Knigge, U; Rouleau, A; Garbarg, M; Warberg, J

    1994-08-01

    The hypothalamic neurotransmitter histamine (HA) induces arginine vasopressin (AVP) release when administered centrally. We studied and characterized this effect of HA with respect to receptor involvement. In addition, we studied the possible role of hypothalamic histaminergic neurons in the mediation of a physiological stimulus (dehydration) for AVP secretion. Intracerebroventricular administration of HA, the H1-receptor agonists 2(3-bromophenyl)HA and 2-thiazolylethylamine, or the H2-receptor agonists amthamine or 4-methyl-HA stimulated AVP secretion. The stimulatory action of HA on AVP was inhibited by pretreatment with the H1-receptor antagonist mepyramine or the H2-receptor antagonist cimetidine. Twenty-four hours of dehydration elevated the plasma osmolality from 298 +/- 3 to 310 +/- 3 mmol/liter and increased the plasma AVP concentration 4-fold. The hypothalamic content of HA and its metabolite tele-methyl-HA was elevated in response to dehydration, indicating an increased synthesis and release of hypothalamic HA. Dehydration-induced AVP secretion was lowered when neuronal HA synthesis was inhibited by the administration of (S) alpha-fluoromethylhistidine or when the animals were pretreated with the H3-receptor agonist R(alpha)methylhistamine, which inhibits the release and synthesis of HA, the H1-receptor antagonists mepyramine and cetirizine, or the H2-receptor antagonists cimetidine and ranitidine. We conclude that HA, via activation of both H1- and H2-receptors, stimulates AVP release and that HA is a physiological regulator of AVP secretion.

  5. DESIGN OF LEARNING MATERIALS ON LIMIT FUNCTION BASED MATHEMATICAL UNDERSTANDING

    Directory of Open Access Journals (Sweden)

    Muchamad Subali Noto

    2018-02-01

    Full Text Available In learning process, students are currently cannot be separated from learning difficulties, including the study material algebra limit function. It because the level of students' mathematical understanding regarding the material is still quite low. This study aimed to analyze the barriers to student learning, designing learning materials based on the material mathematics understanding algebra limit function is valid, determine teacher intervention during the implementation of learning materials and to analyze barriers to student learning after the implementation of learning materials. This research is a qualitative research study design using the form Didactical Design Research. Stages of research conducted: 1 analysis of the situation didactic before learning, 2 analysis of metapedadidatik and 3 the retrospective analysis. Data collection techniques used were tests, interviews, questionnaires, and documentation. The instrument used was a matter TKPM (Comprehension Mathematical Ability Test, interview, validation sheet materials, and documentation guidelines. Research results obtained are students experiencing obstacle to learning the material limit algebra functions. These obstacles are 1 students' difficulties in relating the material prerequisites to limit problems. 2 students can not write properly limit symbol, 3 students can not apply a limit theorem, 4 students are not able to determine the limit value at one point, and 5 students cannot determine the value of the limit at infinity. Learning materials that have been made have validation level of  with very valid criteria. The response was given when the student intervention, generally in accordance with response prediction so that interventions carried out in accordance with the design that has been made. After learning materials student learning obstacles implemented reduced/minimized.

  6. Neuroendocrine mechanisms during reversible hypovolaemic shock in humans with emphasis on the histaminergic and serotonergic system.

    Science.gov (United States)

    Matzen, S H

    1995-01-01

    measurements at a low and high frequency current. The low frequency current, passing extracellular fluid only, changing more than the high frequency current that passes extra as well as intracellular fluid. Central hypovolaemia was found to stimulate the pituitary-adrenal axis, and the development of hypotension strongly increases plasma ACTH, beta-END, cortisol and PRL. Blocking histaminergic receptors did not change the pituitary-adrenal response to central hypovolaemia, while the sympathoadrenal response was affected by histaminergic receptor blockade. The H2-receptor antagonist cimetidine inhibited plasma A, while the H1-receptor antagonist mepyramine attenuated plasma NA and reduced cardiovascular tolerance, and also induced some sedation. A possible effect of sedation and anxiolysis was investigated by administration of the GABAergic drug diazepam. This drug did not change the cardiovascular response to head-up tilt, but reduced the increase in plasma cortisol. This indicates that the appearance of presyncopal symptoms is not related to "stress" but associated with the cardiovascular effects of central hypovolaemia. Another endogenous substance, serotonin (5-HT), may be also involved in cardiovascular as well as endocrine regulation. We investigated the effect of blocking three main receptors on the development and effects of hypovolaemic shock. Methysergide (5-Ht1+2-receptor antagonist) attenuated plasma NA, beta-END, PRL and PRA during tilt with a slight reduction of cardiovascular tolerance. The 5-HT2-receptor antagonist ketanserin reduced cardiovascular tolerance without significant effects on the hormonal responses. The 5-HT3-receptor antagonist ondansetron inhibited the plasma CGRP and adrenalin response to central hypovolaemia without influencing cardiovascular tolerance. It is concluded that the head-up tilted model in humans can be applied to study cardiovascular and endocrine mechanisms until the development of hypovolaemic shock.(ABSTRACT TRUNCATED)

  7. Sandy Soil Microaggregates: Rethinking Our Understanding of Hydraulic Function

    Energy Technology Data Exchange (ETDEWEB)

    Paradiś, Ashley; Brueck, Christopher; Meisenheimer, Douglas; Wanzek, Thomas; Dragila, Maria Ines

    2017-01-01

    This study investigated the peculiar structure of microaggregates in coarse sandy soils that exhibit only external porosity and investigated their control on soil hydrology. The microstructure underpins a hydrologic existence that differs from finer textured soils where aggregates have internal porosity. Understanding the impact of these microaggregates on soil hydrology will permit improved agricultural irrigation management and estimates associated with ecosystem capacity and resiliency. Microstructure was investigated using a digital microscope, and aspects of the structure were quantified by sedimentation and computed microtomography. Sandy soil microaggregates were observed to be comprised of a solid sand-grain core that is coated with fines, presumably cemented by organic media. This microstructure leads to three distinct water pools during drainage: capillary water, followed by thick films (1–20 μm) enveloping the outer surfaces of the crusted microaggregates, followed by adsorbed thin films (<1 μm). The characteristics of the thick films were investigated using an analytical model. These films may provide as much as 10 to 40% saturation in the range of plant-available water. Using lubrication theory, it was predicted that thick film drainage follows a power law function with an exponent of 2. Thick films may also have a role in the geochemical evolution of soils and in ecosystem function because they provide contiguous water and gas phases at relatively high moisture contents. And, because the rough outer crust of these microaggregates can provide good niches for microbial activity, biofilm physics will dominate thick film processes, and consequently hydrologic, biologic, and geochemical functions for coarse sandy soils.

  8. Comparative Auditory Neuroscience: Understanding the Evolution and Function of Ears.

    Science.gov (United States)

    Manley, Geoffrey A

    2017-02-01

    Comparative auditory studies make it possible both to understand the origins of modern ears and the factors underlying the similarities and differences in their performance. After all lineages of land vertebrates had independently evolved tympanic middle ears in the early Mesozoic era, the subsequent tens of millions of years led to the hearing organ of lizards, birds, and mammals becoming larger and their upper frequency limits higher. In extant species, lizard papillae remained relatively small (70 mm (made possible by coiling), as do their upper frequency limits (from 12 to >200 kHz). The auditory organs of the three amniote groups differ characteristically in their cellular structure, but their hearing sensitivity and frequency selectivity within their respective hearing ranges hardly differ. In the immediate primate ancestors of humans, the cochlea became larger and lowered its upper frequency limit. Modern humans show an unusual trend in frequency selectivity as a function of frequency. It is conceivable that the frequency selectivity patterns in humans were influenced in their evolution by the development of speech.

  9. Investigation of Peripheral Effects of Citrus Limon Essential Oil on Somatic Pain in Male Wistar Rats: Role of Histaminergic System

    Directory of Open Access Journals (Sweden)

    Ali Mojtahedin

    2016-12-01

    Full Text Available Background & Objective: One of the plants used in traditional medicine is lemon which has analgesic effect. However, little research has been performed on the analgesic effect of lemon and mechanisms of action with an emphasis on neurotransmitters systems. Therefore, the present study set to investigate the peripheral effects of lemon essential oil on somatic pain using formalin test with an emphasis on histaminergic system in male Wistar rats. Materiala & Methods: Sixty male rats weighing approximately 200-250g and aged 14-16 wk were divided into 10 groups: sham (Salin + Formalin 1% intraplantar, three treatment groups with lemon essential oil (EO (12.5, 25 and 50 mg/kg, three treatment groups with Chlorpheniramine (5, 10 and 20 mg/kg, 1 treatment group with Histamine (10 mg/kg, 1 pretreatment group with Chlorpheniramine (20 mg/kg + EO (50mg/kg, and 1 pretreatment group with Histamine (10 mg/kg + EO (50 mg/kg. Formalin test was used to assess somatic pain. Data analysis was performed using one-way ANOVA. Results:  Intraperitoneal injection of lemon essential oil reduced the pain response induced by formalin in both phases (P<0.05. Pretreatment with chlorpheniramine and lemon essential oil enhanced the analgesic response in both phases (P<0.05. Conclusion: Lemon essential oil had analgesic effects, probably caused by the histaminergic system.

  10. Developing high-performance cross-functional teams: Understanding motivations, functional loyalties, and teaming fundamentals

    Energy Technology Data Exchange (ETDEWEB)

    Miller, M.A.

    1996-08-01

    Teamwork is the key to the future of effective technology management. Today`s technologies and markets have become too complex for individuals to work alone. Global competition, limited resources, cost consciousness, and time pressures have forced organizations and project managers to encourage teamwork. Many of these teams will be cross-functional teams that can draw on a multitude of talents and knowledge. To develop high-performing cross-functional teams, managers must understand motivations, functional loyalties, and the different backgrounds of the individual team members. To develop a better understanding of these issues, managers can learn from experience and from literature on teams and teaming concepts. When studying the literature to learn about cross-functional teaming, managers will find many good theoretical concepts, but when put into practice, these concepts have varying effects. This issue of varying effectiveness is what drives the research for this paper. The teaming concepts were studied to confirm or modify current understanding. The literature was compared with a {open_quotes}ground truth{close_quotes}, a survey of the reality of teaming practices, to examine the teaming concepts that the literature finds to be critical to the success of teams. These results are compared to existing teams to determine if such techniques apply in real-world cases.

  11. A genetic approach to understanding asthma and lung function development

    DEFF Research Database (Denmark)

    Kreiner-Møller, Eskil

    2014-01-01

    Asthma is a common heritable disease of the airways with recurrent episodes of symptoms and reversible airflow obstruction that has increased dramatically in prevalence. The disease is highly heterogeneous with varying age at onset and clinical presentation and most likely represents several...... their effect. In paper I, we investigated the known effect of adult lung function loci on the development of lung function and bronchial responsiveness in children from birth until 7 years of age in the COPSAC2000 birth cohort of 411 children. We measured lung function and bronchial responsiveness at one month...... of age using the raised volume rapid thoracoabdominal compression technique in sedated neonates and repeated the measurements at age 7 utilizing traditional spirometry assessments. Lung function genetic variants identified in adults were not associated with neonatal lung function or bronchial...

  12. Comparative Auditory Neuroscience: Understanding the Evolution and Function of Ears

    OpenAIRE

    Manley, Geoffrey A.

    2016-01-01

    Comparative auditory studies make it possible both to understand the origins of modern ears and the factors underlying the similarities and differences in their performance. After all lineages of land vertebrates had independently evolved tympanic middle ears in the early Mesozoic era, the subsequent tens of millions of years led to the hearing organ of lizards, birds, and mammals becoming larger and their upper frequency limits higher. In extant species, lizard papillae remained relatively s...

  13. The Effects of Histaminergic Agents in the Nucleus ccumbens of Rats in the Elevated Plus-Maze Test of Anxiety

    Directory of Open Access Journals (Sweden)

    Ameneh Rezayof

    2010-05-01

    Full Text Available "n Objective: "n The nucleus accumbens (NAc receive histaminergic neurons from tuberomammillary nuclei. There are reports indicating that central histamine systems are involved in many physiological behavioral processes, including anxiety. The aim of the present study was to assess whether the histaminergic system of the NAc is involved in anxiety-related behaviors. Methods: Rats were anesthetized with intra-peritoneal injection of ketamine hydrochloride, plus xylazine and then were placed in a stereotaxic apparatus. In addition, two stainless-steel cannuale were placed 2 mm above the nucleus accumbens shell. Seven days after recovery from surgery, the behavioral testing was started. As a model of anxiety, the elevated plus maze which is a useful test to investigate the effects of anxiogenic or anxiolytic drugs in rodents, was used in male Wistar rats.  "nResults: Intra-NAc administration of histamine (0.01, 0.1 and 1 µg/rat increased the percentage of open arm time (%OAT and open arm entries (%OAE ,but not locomotor activity, indicating an anxiolytic response. Furthermore, bilateral  microinjections of different doses of the H1 receptor  antagonist pyrilamine (0.001, 0.01, 0.1 and 1 µg/rat or the H2 receptor antagonist ranitidine (0.001, 0.01, 0.1 and 1 µg/rat into the NAc increased %OAT and %OAE , but not locomotor activity. However, both histamine and histamine receptor antagonists showed an anxiolytic-like effect ; the antagonists (1 µg/rat also decreased the histamine response. "n "n Conclusion: The results may indicate a modulatory effect for the H1 and H2 histamine receptors of nucleus accumbens in the anxiety behavior of rats.

  14. Understanding doublecortin-like kinase gene function through transgenesis

    NARCIS (Netherlands)

    Schenk, Geert J.

    2010-01-01

    Doublecortin (DCX) and DCX-domain containing Doublecortin-Like Kinase (DCLK) gene splice variants function during embryonic development, where they play a role in microtubule binding. Although a role for the DCLK gene during embryogenesis is clearly established, it encodes multiple, different

  15. Associations among False Belief Understanding, Counterfactual Reasoning, and Executive Function

    Science.gov (United States)

    Guajardo, Nicole R.; Parker, Jessica; Turley-Ames, Kandi

    2009-01-01

    The primary purposes of the present study were to clarify previous work on the association between counterfactual thinking and false belief performance to determine (1) whether these two variables are related and (2) if so, whether executive function skills mediate the relationship. A total of 92 3-, 4-, and 5-year-olds completed false belief,…

  16. Understanding and quantifying urban forest structure, functions, and value

    Science.gov (United States)

    David J. Nowak; Daniel E. Crane; Jeffrey T. Walton; Daniel B. Twardus; John F. Dwyer

    2002-01-01

    Trees in urban areas can have a significant impact on human health and the environment. Unfortunately, there is relatively little data about the structure, health, functions, and long-term changes in this important resource. In the United States, a number of efforts are underway to assess urban forest attributes at the local to national scales. In addition, tools are...

  17. Functional health literacy and healthy eating: Understanding the brazilian food guide recommendations

    Directory of Open Access Journals (Sweden)

    Maria Auristela Magalhães Coelho

    2014-12-01

    Full Text Available Objective: To assess the relationship between the functional health literacy of Unified Heath System users and the understanding of food servings in the pocket version of the Brazilian Food Guide. Methods: Functional health literacy was assessed by the Brief Test of functional health literacy. Two dialogue rounds were conducted with patients with adequate functional health literacy (Group 1 and inadequate functional health literacy (Group 2. The dialogues were recorded and analyzed according to the discourse of the collective subject. Results: Most (58.0% users had inadequate functional health literacy. Five core areas were identified: understands serving sizes; does not understand serving sizes; serving sizes are confusing; unfamiliar/uncommon foods; small letters. Group 2 had more trouble understanding. Conclusion: Difficulty understanding hinders health promotion. Individuals need to have access to educational materials that are easier to understand and developed taking their functional health literacy into account.

  18. Nitrogen cycling in corals: the key to understanding holobiont functioning?

    KAUST Repository

    Rädecker, Nils

    2015-04-01

    Corals are animals that form close mutualistic associations with endosymbiotic photosynthetic algae of the genus Symbiodinium. Together they provide the calcium carbonate framework of coral reef ecosystems. The importance of the microbiome (i.e., bacteria, archaea, fungi, and viruses) to holobiont functioning has only recently been recognized. Given that growth and density of Symbiodinium within the coral host is highly dependent on nitrogen availability, nitrogen-cycling microbes may be of fundamental importance to the stability of the coral–algae symbiosis and holobiont functioning, in particular under nutrient-enriched and -depleted scenarios. We summarize what is known about nitrogen cycling in corals and conclude that disturbance of microbial nitrogen cycling may be tightly linked to coral bleaching and disease.

  19. Students' Understanding of the General Notion of a Function of Two Variables

    Science.gov (United States)

    Martinez-Planell, Rafael; Trigueros Gaisman, Maria

    2012-01-01

    In this study we analyze students' understanding of two-variable function; in particular we consider their understanding of domain, possible arbitrary nature of function assignment, uniqueness of function image, and range. We use APOS theory and semiotic representation theory as a theoretical framework to analyze data obtained from interviews with…

  20. Histamine Regulates the Inflammatory Profile of SOD1-G93A Microglia and the Histaminergic System Is Dysregulated in Amyotrophic Lateral Sclerosis

    Directory of Open Access Journals (Sweden)

    Savina Apolloni

    2017-11-01

    Full Text Available Amyotrophic lateral sclerosis (ALS is a late-onset motor neuron disease where activated glia release pro-inflammatory cytokines that trigger a vicious cycle of neurodegeneration in the absence of resolution of inflammation. Given the well-established role of histamine as a neuron-to-glia alarm signal implicated in brain disorders, the aim of this study was to investigate the expression and regulation of the histaminergic pathway in microglial activation in ALS mouse model and in humans. By examining the contribution of the histaminergic system to ALS, we found that particularly via H1 and H4 receptors, histamine promoted an anti-inflammatory profile in microglia from SOD1-G93A mice by modulating their activation state. A decrease in NF-κB and NADPH oxidase 2 with an increase in arginase 1 and P2Y12 receptor was induced by histamine only in the ALS inflammatory environment, but not in the healthy microglia, together with an increase in IL-6, IL-10, CD163, and CD206 phenotypic markers in SOD1-G93A cells. Moreover, histaminergic H1, H2, H3, and H4 receptors, and histamine metabolizing enzymes histidine decarboxylase, histamine N-methyltransferase, and diamine oxidase were found deregulated in spinal cord, cortex, and hypothalamus of SOD1-G93A mice during disease progression. Finally, by performing a meta-analysis study, we found a modulated expression of histamine-related genes in cortex and spinal cord from sporadic ALS patients. Our findings disclose that histamine acts as anti-inflammatory agent in ALS microglia and suggest a dysregulation of the histaminergic signaling in ALS.

  1. Students' Understanding of the Function-Derivative Relationship When Learning Economic Concepts

    Science.gov (United States)

    Ariza, Angel; Llinares, Salvador; Valls, Julia

    2015-01-01

    The aim of this study is to characterise students' understanding of the function-derivative relationship when learning economic concepts. To this end, we use a fuzzy metric (Chang 1968) to identify the development of economic concept understanding that is defined by the function-derivative relationship. The results indicate that the understanding…

  2. Developing Essential Understanding of Functions for Teaching Mathematics in Grades 9-12

    Science.gov (United States)

    Lloyd, Gwendolyn; Beckmann, Sybilla; Zbiek, Rose Mary; Cooney, Thomas

    2010-01-01

    Are sequences functions? What can't the popular "vertical line test" be applied in some cases to determine if a relation is a function? How does the idea of rate of change connect with simpler ideas about proportionality as well as more advanced topics in calculus? Helping high school students develop a robust understanding of functions requires…

  3. Trait-based approaches for understanding microbial biodiversity and ecosystem functioning

    NARCIS (Netherlands)

    Krause, S.; Le Roux, X.; Niklaus, P.A.; van Bodegom, P.M.; Lennon, J.T.; Bertilsson, S.A.; Grossart, H.P.; Philippot, L.; Bodelier, P.L.E.

    2014-01-01

    In ecology, biodiversity-ecosystem functioning (BEF) research has seen a shift in perspective from taxonomy to function in the last two decades, with successful application of trait-based approaches. This shift offers opportunities for a deeper mechanistic understanding of the role of biodiversity

  4. An Active Learning Exercise to Facilitate Understanding of Nephron Function: Anatomy and Physiology of Renal Transporters

    Science.gov (United States)

    Dirks-Naylor, Amie J.

    2016-01-01

    Renal transport is a central mechanism underlying electrolyte homeostasis, acid base balance and other essential functions of the kidneys in human physiology. Thus, knowledge of the anatomy and physiology of the nephron is essential for the understanding of kidney function in health and disease. However, students find this content difficult to…

  5. Risperidone-induced weight gain and reduced locomotor activity in juvenile female rats: The role of histaminergic and NPY pathways.

    Science.gov (United States)

    Lian, Jiamei; De Santis, Michael; He, Meng; Deng, Chao

    2015-01-01

    Second generation antipsychotic drugs (SGAs) such as risperidone are increasingly prescribed (mostly for off-label use) to children and adolescents for treating various mental disorders. SGAs cause serious weight gain/obesity and other metabolic side-effects. This study aimed to establish an animal model of risperidone-induced weight gain in female juvenile rats, and to investigate the effects of risperidone on the expression of hypothalamic histaminergic H1 receptors (H1R) and neuropeptides, and their association with weight gain. Female Sprague Dawley rats were treated orally with risperidone (0.3mg/kg, 3 times/day) or vehicle (control) starting from postnatal day (PD) 23 (±1 day) for 3 weeks (a period corresponding to the childhood-adolescent period in humans). In the female juvenile rats, risperidone treatment increased food intake and body weight gain, which started to appear after 12 days' treatment. Risperidone also significantly decreased the locomotor activity of the female rats. Consistently, risperidone significantly elevated mRNA expression of hypothalamic H1R, neuropeptide Y (NPY), and agouti-related peptide (AgRP) compared to controls, and H1R and NPY levels were correlated with risperidone enhanced weight gain and food intake in the female juvenile rats. However, risperidone did not affect hypothalamic proopiomelanocortin (POMC) and cocaine- and amphetamine-regulated transcript (CART) mRNA expression. Therefore, these results suggested that risperidone elevated appetite and body weight gain in juveniles via regulation of the hypothalamic H1R, NPY and AgRP pathways, as well as by reducing activity. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Physical models have gender‐specific effects on student understanding of protein structure–function relationships

    Science.gov (United States)

    Harris, Michelle A.; Chang, Wesley S.; Dent, Erik W.; Nordheim, Erik V.; Franzen, Margaret A.

    2016-01-01

    Abstract Understanding how basic structural units influence function is identified as a foundational/core concept for undergraduate biological and biochemical literacy. It is essential for students to understand this concept at all size scales, but it is often more difficult for students to understand structure–function relationships at the molecular level, which they cannot as effectively visualize. Students need to develop accurate, 3‐dimensional mental models of biomolecules to understand how biomolecular structure affects cellular functions at the molecular level, yet most traditional curricular tools such as textbooks include only 2‐dimensional representations. We used a controlled, backward design approach to investigate how hand‐held physical molecular model use affected students' ability to logically predict structure–function relationships. Brief (one class period) physical model use increased quiz score for females, whereas there was no significant increase in score for males using physical models. Females also self‐reported higher learning gains in their understanding of context‐specific protein function. Gender differences in spatial visualization may explain the gender‐specific benefits of physical model use observed. © 2016 The Authors Biochemistry and Molecular Biology Education published by Wiley Periodicals, Inc. on behalf of International Union of Biochemistry and Molecular Biology, 44(4):326–335, 2016. PMID:26923186

  7. Physical models have gender-specific effects on student understanding of protein structure-function relationships.

    Science.gov (United States)

    Forbes-Lorman, Robin M; Harris, Michelle A; Chang, Wesley S; Dent, Erik W; Nordheim, Erik V; Franzen, Margaret A

    2016-07-08

    Understanding how basic structural units influence function is identified as a foundational/core concept for undergraduate biological and biochemical literacy. It is essential for students to understand this concept at all size scales, but it is often more difficult for students to understand structure-function relationships at the molecular level, which they cannot as effectively visualize. Students need to develop accurate, 3-dimensional mental models of biomolecules to understand how biomolecular structure affects cellular functions at the molecular level, yet most traditional curricular tools such as textbooks include only 2-dimensional representations. We used a controlled, backward design approach to investigate how hand-held physical molecular model use affected students' ability to logically predict structure-function relationships. Brief (one class period) physical model use increased quiz score for females, whereas there was no significant increase in score for males using physical models. Females also self-reported higher learning gains in their understanding of context-specific protein function. Gender differences in spatial visualization may explain the gender-specific benefits of physical model use observed. © 2016 The Authors Biochemistry and Molecular Biology Education published by Wiley Periodicals, Inc. on behalf of International Union of Biochemistry and Molecular Biology, 44(4):326-335, 2016. © 2016 The International Union of Biochemistry and Molecular Biology.

  8. The Effects of an Undergraduate Algebra Course on Prospective Middle School Teachers' Understanding of Functions, Especially Quadratic Functions

    Science.gov (United States)

    Duarte, Jonathan T.

    2010-01-01

    Although current reform movements have stressed the importance of developing prospective middle school mathematics teachers' subject matter knowledge and understandings, there is a dearth of research studies with regard to prospective middle school teachers' confidence and knowledge with respect to quadratic functions. This study was intended to…

  9. The challenges of understanding glycolipid functions: An open outlook based on molecular simulations

    DEFF Research Database (Denmark)

    Manna, M.; Rog, T.; Vattulainen, I.

    2014-01-01

    and molecular simulations can be used to shed light on the role of glycolipids in membrane structure and dynamics, receptor function, and other phenomena related to emergence of diseases such as Parkinson's. The cases we discuss highlight the challenge to understand how glycolipids function in cell membranes......Glycolipids are the most complex lipid type in cell membranes, characterized by a great diversity of different structures and functions. The underlying atomistic/molecular interactions and mechanisms associated with these functions are not well understood. Here we discuss how atomistic...

  10. Improving understanding of the functional diversity of fisheries by exploring the influence of global catch reconstruction.

    Science.gov (United States)

    Nash, Kirsty L; Watson, Reg A; Halpern, Benjamin S; Fulton, Elizabeth A; Blanchard, Julia L

    2017-09-06

    Functional diversity is thought to enhance ecosystem resilience, driving research focused on trends in the functional composition of fisheries, most recently with new reconstructions of global catch data. However, there is currently little understanding of how accounting for unreported catches (e.g. small-scale and illegal fisheries, bycatch and discards) influences functional diversity trends in global fisheries. We explored how diversity estimates varied among reported and unreported components of catch in 2010, and found these components had distinct functional fingerprints. Incorporating unreported catches had little impact on global-scale functional diversity patterns. However, at smaller, management-relevant scales, the effects of incorporating unreported catches were large (changes in functional diversity of up to 46%). Our results suggest there is greater uncertainty about the risks to ecosystem integrity and resilience from current fishing patterns than previously recognized. We provide recommendations and suggest a research agenda to improve future assessments of functional diversity of global fisheries.

  11. The construction of an amino acid network for understanding protein structure and function.

    Science.gov (United States)

    Yan, Wenying; Zhou, Jianhong; Sun, Maomin; Chen, Jiajia; Hu, Guang; Shen, Bairong

    2014-06-01

    Amino acid networks (AANs) are undirected networks consisting of amino acid residues and their interactions in three-dimensional protein structures. The analysis of AANs provides novel insight into protein science, and several common amino acid network properties have revealed diverse classes of proteins. In this review, we first summarize methods for the construction and characterization of AANs. We then compare software tools for the construction and analysis of AANs. Finally, we review the application of AANs for understanding protein structure and function, including the identification of functional residues, the prediction of protein folding, analyzing protein stability and protein-protein interactions, and for understanding communication within and between proteins.

  12. Students' Perceptions and Development of Conceptual Understanding Regarding Trigonometry and Trigonometric Function

    Science.gov (United States)

    Cetin, Omer Faruk

    2015-01-01

    This study aims to analyse university level mathematics education students' perceptions on conceptual understanding of trigonometry and trigonometric functions and their content development of these concepts. A case study was conducted with 90 freshman students of Elementary Mathematics Department. The data were gathered via a scale; they included…

  13. Dynamic Graphics in Excel for Teaching Statistics: Understanding the Probability Density Function

    Science.gov (United States)

    Coll-Serrano, Vicente; Blasco-Blasco, Olga; Alvarez-Jareno, Jose A.

    2011-01-01

    In this article, we show a dynamic graphic in Excel that is used to introduce an important concept in our subject, Statistics I: the probability density function. This interactive graphic seeks to facilitate conceptual understanding of the main aspects analysed by the learners.

  14. An Epistemological Inquiry into Organic Chemistry Education: Exploration of Undergraduate Students' Conceptual Understanding of Functional Groups

    Science.gov (United States)

    Akkuzu, Nalan; Uyulgan, Melis Arzu

    2016-01-01

    This study sought to determine the levels of conceptual understanding of undergraduate students regarding organic compounds within different functional groups. A total of 60 students who were enrolled in the Department of Secondary Science and Mathematics Education of a Faculty of Education at a state university in Turkey and who had followed an…

  15. Urban ecological stewardship: understanding the structure, function and network of community-based urban land management

    Science.gov (United States)

    Erika s. Svendsen; Lindsay K. Campbell

    2008-01-01

    Urban environmental stewardship activities are on the rise in cities throughout the Northeast. Groups participating in stewardship activities range in age, size, and geography and represent an increasingly complex and dynamic arrangement of civil society, government and business sectors. To better understand the structure, function and network of these community-based...

  16. Integrating Model-Based Learning and Animations for Enhancing Students' Understanding of Proteins Structure and Function

    Science.gov (United States)

    Barak, Miri; Hussein-Farraj, Rania

    2013-01-01

    This paper describes a study conducted in the context of chemistry education reforms in Israel. The study examined a new biochemistry learning unit that was developed to promote in-depth understanding of 3D structures and functions of proteins and nucleic acids. Our goal was to examine whether, and to what extent teaching and learning via…

  17. Understanding heavy-oil molecular functionality and relations to fluid properties

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, S.I. [Schlumberger, DBR Technology Center, Edmonton AB (Canada)

    2011-07-01

    In the heavy oil industry, knowing oil properties is important to optimizing recovery, transport and refinery. Nitrogen, sulfur and oxygen compounds (NSOs) have an important impact on these properties but this is often overlooked. The purpose of this paper is to analyze the impact of functional groups in connection with heavy oil and asphaltenes. Experiments were carried out with asphaltenes altered by chemical surgery that removed specific functional interactions. Titration calorimetry and fluorescence spectroscopy were then done. Results highlighted the fact that functional groups are of key importance in the determination of heavy oil properties and that acidity can be considered the most important interaction. This paper demonstrated that the determination of specific interactions could be more important in assessing heavy oil properties than understanding their hydrocarbon structure; further work is needed to fully understand the role of sulfur and nitrogen species.

  18. Projection from the prefrontal cortex to histaminergic cell groups in the posterior hypothalamic region of the rat. Anterograde tracing with Phaseolus vulgaris leucoagglutinin combined with immunocytochemistry of histidine decarboxylase

    NARCIS (Netherlands)

    Wouterlood, F.G.; Steinbusch, H.W.M.; Luiten, P.G.M.; Bol, J.G.J.M.

    1987-01-01

    We investigated the projection from the infralimbic division of the prefrontal cortex (area 25) to histaminergic neurons in the posterior hypothalamic area. Phaseolus vulgaris-leucoagglutinin (PHA-L) was injected in the prefrontal cortex of rats. Frozen brain sections were subjected to combined

  19. Recent advances in understanding lung function development [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Erik Melén

    2017-05-01

    Full Text Available Recent years have witnessed critical contributions to our understanding of the determinants and long-term implications of lung function development. In this article, we review studies that have contributed to advances in understanding lung function development and its critical importance for lung health into adult life. In particular, we have focused on early life determinants that include genetic factors, perinatal events, environmental exposures, lifestyle, infancy lower respiratory tract infections, and persistent asthma phenotypes. Longitudinal studies have conclusively demonstrated that lung function deficits that are established by school age may track into adult life and increase the risk of adult lung obstructive diseases, such as chronic obstructive pulmonary disease. Furthermore, these contributions have provided initial evidence in support of a direct influence by early life events on an accelerated decline of lung function and an increased susceptibility to its environmental determinants well into adult life. As such, we argue that future health-care programs based on precision medicine approaches that integrate deep phenotyping with tailored medication and advice to patients should also foster optimal lung function growth to be fully effective.

  20. The Importance of Understanding Hierarchical Relations between High Order Mental Functions in Clinical Practice

    Directory of Open Access Journals (Sweden)

    Benedetto Farina

    2015-04-01

    Full Text Available The state-of-the-art in studies on mentalization suggests that capacity to understand other minds (mindreading, self introspection and consciousness, mental time travel in the past and the present, linguistic communication, are different components of a hierarchical organization of several functions reflecting the evolutionary development of the specie and integrates increasingly complex, mutually coordinated brain levels. The understanding of the precise hierarchical relations between them, that reflect the phylo- and ontogenetic evolutionary pathway for adaptation to the complex interpersonal and socio-cultural environment, has an essential application in psychopathology and psychotherapy, in particular for those clinical conditions where the normal integration of high order mental functions is hampered by developmental relational trauma.

  1. Understanding how prevocational training on care farms can lead to functioning, motivation and well-being.

    Science.gov (United States)

    Ellingsen-Dalskau, Lina H; Berget, Bente; Pedersen, Ingeborg; Tellnes, Gunnar; Ihlebæk, Camilla

    2016-12-01

    Prevocational training aims to improve basic vocational and social skills, supporting return to work for people who have been out of work for a long time. Care farms provide prevocational training; the aim of the study was to use the self-determination theory to gain an understanding of how these programmes can lead to healthy functioning and motivation for clients. A total of 194 participants in prevocational training on care farms answered questions about demographic information, their perception of being a colleague, the social community on the farm, experiencing nature and animals and need satisfaction. A cross-sectional design resulting in a structural equation model was used to understand how elements of the care farm context influence satisfaction of three psychological needs. The results showed that a feeling of being a useful colleague led to competence, experiencing a sense of group belonging led to relatedness and autonomy, while receiving social support from the farmer led to satisfaction of all three needs for the participants. The results explain how prevocational training can stimulate participants' functionality, motivation and well-being. This understanding enables initiators and managers of prevocational training to understand and further strengthen the need-supportive elements of such programmes. Implications for Rehabilitation Prevocational training on care farms can facilitate motivation, functioning and well-being for clients. Making clients feel like useful colleagues that belong to a client group will strengthen the positive qualities of these programmes. Support, understanding and acknowledgement from the farmer are the most important elements for a positive development for the clients.

  2. Ecosystem function in waste stabilisation ponds: Improving water quality through a better understanding of biophysical coupling

    Science.gov (United States)

    Ghadouani, Anas; Reichwaldt, Elke S.; Coggins, Liah X.; Ivey, Gregory N.; Ghisalberti, Marco; Zhou, Wenxu; Laurion, Isabelle; Chua, Andrew

    2014-05-01

    Wastewater stabilisation ponds (WSPs) are highly productive systems designed to treat wastewater using only natural biological and chemical processes. Phytoplankton, microbial communities and hydraulics play important roles for ecosystem functionality of these pond systems. Although WSPs have been used for many decades, they are still considered as 'black box' systems as very little is known about the fundamental ecological processes which occur within them. However, a better understanding of how these highly productive ecosystems function is particularly important for hydrological processes, as treated wastewater is commonly discharged into streams, rivers, and oceans, and subject to strict water quality guidelines. WSPs are known to operate at different levels of efficiency, and treatment efficiency of WSPs is dependent on physical (flow characteristics and sludge accumulation and distribution) and biological (microbial and phytoplankton communities) characteristics. Thus, it is important to gain a better understanding of the role and influence of pond hydraulics and vital microbial communities on pond performance and WSP functional stability. The main aim of this study is to investigate the processes leading to differences in treatment performance of WSPs. This study uses a novel and innovative approach to understand these factors by combining flow cytometry and metabolomics to investigate various biochemical characteristics, including the metabolite composition and microbial community within WSPs. The results of these analyses will then be combined with results from the characterisation of pond hydrodynamics and hydraulic performance, which will be performed using advanced hydrodynamic modelling and advanced sludge profiling technology. By understanding how hydrodynamic and biological processes influence each other and ecosystem function and stability in WSPs, we will be able to propose ways to improve the quality of the treatment using natural processes, with

  3. Understanding, predicting and controlling the physicochemical functionality of rice protein ingredients

    OpenAIRE

    Amagliani, Luca

    2016-01-01

    The aim of this research was to characterise the nutrient composition and protein profile of a range of intact and hydrolysed rice protein ingredients, to benchmark their physicochemical properties against those of selected commercial dairy protein ingredients, and to develop tailored solutions for understanding, predicting, modifying and controlling their functionality in food systems. The rice protein ingredients studied had protein contents in the range 32-78%, and lower levels of calcium ...

  4. Integrating Model-Based Learning and Animations for Enhancing Students' Understanding of Proteins Structure and Function

    Science.gov (United States)

    Barak, Miri; Hussein-Farraj, Rania

    2013-04-01

    This paper describes a study conducted in the context of chemistry education reforms in Israel. The study examined a new biochemistry learning unit that was developed to promote in-depth understanding of 3D structures and functions of proteins and nucleic acids. Our goal was to examine whether, and to what extent teaching and learning via model-based learning and animations of biomolecules affect students' chemical understanding. Applying the mixed methods research paradigm, pre- and post-questionnaires as well as class-observations were employed in the collection, analysis, and interpretation of data. The research population included 175 grade twelve students, divided into three research groups: (a) hands-on exploration of animations, (b) teacher's demonstrations of animations, (c) traditional learning using textbooks. Findings indicated that the integration of model-based learning and 3D animations enhanced students' understanding of proteins' structure and function and their ability to transfer across different levels of chemistry understanding. Findings also indicated that teachers' demonstrations of animations may enhance students' `knowledge'—a low order thinking skill; however, in order to enhance higher levels of thinking, students should be able to explore 3D animations on their own. Applying constructivist and interpretative analysis of the data, three themes were raised, corresponding to cognitive, affective, and social aspects of learning while exploring web-based models and animations.

  5. Trait-based approaches for understanding microbial biodiversity and ecosystem functioning.

    Science.gov (United States)

    Krause, Sascha; Le Roux, Xavier; Niklaus, Pascal A; Van Bodegom, Peter M; Lennon, Jay T; Bertilsson, Stefan; Grossart, Hans-Peter; Philippot, Laurent; Bodelier, Paul L E

    2014-01-01

    In ecology, biodiversity-ecosystem functioning (BEF) research has seen a shift in perspective from taxonomy to function in the last two decades, with successful application of trait-based approaches. This shift offers opportunities for a deeper mechanistic understanding of the role of biodiversity in maintaining multiple ecosystem processes and services. In this paper, we highlight studies that have focused on BEF of microbial communities with an emphasis on integrating trait-based approaches to microbial ecology. In doing so, we explore some of the inherent challenges and opportunities of understanding BEF using microbial systems. For example, microbial biologists characterize communities using gene phylogenies that are often unable to resolve functional traits. Additionally, experimental designs of existing microbial BEF studies are often inadequate to unravel BEF relationships. We argue that combining eco-physiological studies with contemporary molecular tools in a trait-based framework can reinforce our ability to link microbial diversity to ecosystem processes. We conclude that such trait-based approaches are a promising framework to increase the understanding of microbial BEF relationships and thus generating systematic principles in microbial ecology and more generally ecology.

  6. Trait-based approaches for understanding microbial biodiversity and ecosystem functioning

    Directory of Open Access Journals (Sweden)

    Sascha eKrause

    2014-05-01

    Full Text Available In ecology, biodiversity-ecosystem functioning (BEF research has seen a shift in perspective from taxonomy to function in the last two decades, with successful application of trait-based approaches. This shift offers opportunities for a deeper mechanistic understanding of the role of biodiversity in maintaining multiple ecosystem processes and services. In this paper, we highlight studies that have focused on BEF of microbial communities with an emphasis on integrating trait-based approaches to microbial ecology. In doing so, we explore some of the inherent challenges and opportunities of understanding BEF using microbial systems. For example, microbial biologists characterize communities using gene phylogenies that are often unable to resolve functional traits. Additionally, experimental designs of existing microbial BEF studies are often inadequate to unravel BEF relationships. We argue that combining eco-physiological studies with contemporary molecular tools in a trait-based framework can reinforce our ability to link microbial diversity to ecosystem processes. We conclude that such trait-based approaches are a promising framework to increase the understanding of microbial BEF relationships and thus generating systematic principles in microbial ecology and more generally ecology.

  7. Trait-based approaches for understanding microbial biodiversity and ecosystem functioning

    Science.gov (United States)

    Krause, Sascha; Le Roux, Xavier; Niklaus, Pascal A.; Van Bodegom, Peter M.; Lennon, Jay T.; Bertilsson, Stefan; Grossart, Hans-Peter; Philippot, Laurent; Bodelier, Paul L. E.

    2014-01-01

    In ecology, biodiversity-ecosystem functioning (BEF) research has seen a shift in perspective from taxonomy to function in the last two decades, with successful application of trait-based approaches. This shift offers opportunities for a deeper mechanistic understanding of the role of biodiversity in maintaining multiple ecosystem processes and services. In this paper, we highlight studies that have focused on BEF of microbial communities with an emphasis on integrating trait-based approaches to microbial ecology. In doing so, we explore some of the inherent challenges and opportunities of understanding BEF using microbial systems. For example, microbial biologists characterize communities using gene phylogenies that are often unable to resolve functional traits. Additionally, experimental designs of existing microbial BEF studies are often inadequate to unravel BEF relationships. We argue that combining eco-physiological studies with contemporary molecular tools in a trait-based framework can reinforce our ability to link microbial diversity to ecosystem processes. We conclude that such trait-based approaches are a promising framework to increase the understanding of microbial BEF relationships and thus generating systematic principles in microbial ecology and more generally ecology. PMID:24904563

  8. Understanding the cognitive underpinnings of functional impairments in early dementia: a review.

    Science.gov (United States)

    Giebel, Clarissa M; Challis, David; Montaldi, Daniela

    2015-01-01

    Early dementia is marked by cognitive and functional impairments, and although studies indicate an association between these, detailed analyses exploring this relationship are rare. It is crucial to understand how specific cognitive deficits underlie functional deficits to develop successful cognitive interventions. This paper reviews the evidence of impairment in everyday functioning and in working, long-term and prospective memory in early dementia. Findings are evaluated with respect to the relationship between cognitive and functional impairments. From the literature searches, 17 studies on everyday functioning and 40 studies on memory were obtained. Studies were only included if patients had an official diagnosis and were in the early stages of dementia. Complex instrumental activities of daily living were subject to greater impairment than basic activities of daily living. In particular, early dementia patients struggle with finance tasks; a deficit linked to impaired working memory. Regarding cognition, long-term memory is the earliest form of memory to decline as is well recognised. Evidence also indicates deficits in working and prospective memory, with inconsistent evidence about impairments of the former. A major limitation of the literature is a lack of studies assessing individual everyday activities and the associated error patterns that might occur. This review critically assesses the status of translational research for everyday activities in early dementia, an area with critical implications for cognitive-based rehabilitation. Further research is required into the detailed assessment of individual everyday activity and specific memory deficits, in order to effectively map cognitive functions onto functional performance.

  9. Understanding immune function as a pace of life trait requires environmental context.

    Science.gov (United States)

    Tieleman, B Irene

    2018-01-01

    This article provides a brief historical perspective on the integration of physiology into the concept of the pace of life of birds, evaluates the fit of immune function into this framework, and asks what it will take to fruitfully understand immune functioning of birds in pace of life studies in the future. In the late 1970s, physiology started to seriously enter avian life history ecology, with energy as the main currency of interest, inspired by David Lack's work in the preceding decades emphasizing how food availability explained life history variation. In an effort to understand the trade-off between survival and reproduction, and specifically the mortality costs associated with hard work, in the 1980s and 1990s, other physiological phenomena entered the realm of animal ecologists, including endocrinology, oxidative stress, and immunology. Reviewing studies thus far to evaluate the role of immune function in a life history context and particularly to address the questions whether immune function (1) consistently varies with life history variation among free-living bird species and (2) mediates life history trade-offs in experiments with free-living bird species; I conclude that, unlike energy metabolism, the immune system does not closely covary with life history among species nor mediates the classical trade-offs within individuals. Instead, I propose that understanding the tremendous immunological variation uncovered among free-living birds over the past 25 years requires a paradigm shift. The paradigm should shift from viewing immune function as a costly trait involved in life history trade-offs to explicitly including the benefits of the immune system and placing it firmly in an environmental and ecological context. A first step forward will be to quantify the immunobiotic pressures presented by diverse environmental circumstances that both shape and challenge the immune system of free-living animals. Current developments in the fields of infectious

  10. From Process Understanding Via Soil Functions to Sustainable Soil Management - A Systemic Approach

    Science.gov (United States)

    Wollschlaeger, U.; Bartke, S.; Bartkowski, B.; Daedlow, K.; Helming, K.; Kogel-Knabner, I.; Lang, B.; Rabot, E.; Russell, D.; Stößel, B.; Weller, U.; Wiesmeier, M.; Rabot, E.; Vogel, H. J.

    2017-12-01

    Fertile soils are central resources for the production of biomass and the provision of food and energy. A growing world population and latest climate targets lead to an increasing demand for both, food and bio-energy, which requires preserving and improving the long-term productivity of soils as a bio-economic resource. At the same time, other soil functions and ecosystem services need to be maintained: filter for clean water, carbon sequestration, provision and recycling of nutrients, and habitat for biological activity. All these soil functions result from the interaction of a multitude of physical, chemical and biological processes that are not yet sufficiently understood. In addition, we lack understanding about the interplay between the socio-economic system and the soil system and how soil functions benefit human wellbeing. Hence, a solid and integrated assessment of soil quality requires the consideration of the ensemble of soil functions and its relation to soil management to finally be able to develop site-specific options for sustainable soil management. We present an integrated modeling approach that investigates the influence of soil management on the ensemble of soil functions. It is based on the mechanistic relationships between soil functional attributes, each explained by a network of interacting processes as derived from scientific evidence. As the evidence base required for feeding the model is for the most part stored in the existing scientific literature, another central component of our work is to set up a public "knowledge-portal" providing the infrastructure for a community effort towards a comprehensive knowledge base on soil processes as a basis for model developments. The connection to the socio-economic system is established using the Drivers-Pressures-Impacts-States-Responses (DPSIR) framework where our improved understanding about soil ecosystem processes is linked to ecosystem services and resource efficiency via the soil functions.

  11. ASSESSING CONCEPTUAL UNDERSTANDING IN MATHEMATICS: Using Derivative Function to Solve Connected Problems

    Directory of Open Access Journals (Sweden)

    Nevin ORHUN

    2013-07-01

    Full Text Available Open and distance education plays an important role in the actualization of cultural goals as well as in societal developments. This is an independent teaching and learning method for mathematics which forms the dynamic of scientific thinking. Distance education is an important alternative to traditional teaching applications. These contributions brought by technology enable students to participate actively in having access to information and questioning it. Such an application increases students’ motivation and teaches how mathematics can be used in daily life. Derivative is a mathematical concept which can be used in many areas of daily life. The aim of this study is to enable the concept of derivatives to be understood well by using the derivative function in the solution of various problems. It also aims at interpreting difficulties theoretically in the solution of problems and determining mistakes in terms of teaching methods. In this study, how various aspects of derivatives are understood is emphasized. These aspects concern the explanation of concepts and process, and also their application to certain concepts in physics. Students’ depth of understanding of derivatives was analyzed based on two aspects of understanding; theoretical analysis and contextual application. Follow-up interviews were conducted with five students. The results show that the students preferred to apply an algebraic symbolic aspect instead of using logical meanings of function and its derivative. In addition, in relation to how the graph of the derivative function affects the aspect of function, it was determined that the students displayed low performance.

  12. Antipruritic Effect of Cold-induced and Transient Receptor Potential-agonist-induced Counter-irritation on Histaminergic Itch in Humans

    DEFF Research Database (Denmark)

    Andersen, Hjalte H.; Melholt, Camilla; Hilborg, Sigurd D.

    2017-01-01

    A frequent empirical observation is that cold-induced counter-irritation may attenuate itch. The aim of this randomized, single-blinded, exploratory study was to evaluate the counter-irritation effects of cold-stimulation and topical application of transient receptor potential TRPA1/M8-agonists...... and trans-cinnamaldehyde had antipruritic efficacy similar to doxepin (p Cold-induced counter-irritation had an inhibitory effect on histaminergic itch, suggesting that agonists of cold transduction receptors could be of potential antipruritic value....... (measured by laser-speckle perfusion-imaging). Homotopic thermal counter-irritation was performed with 6 temperatures, ranging from 4°C to 37°C, using a 3 × 3-cm thermal stimulator. Chemical “cold-like” counter-irritation was conducted with 40% L-menthol and 10% trans-cinnamaldehyde, while 5% doxepin...

  13. Understanding volatility correlation behavior with a magnitude cross-correlation function

    Science.gov (United States)

    Jun, Woo Cheol; Oh, Gabjin; Kim, Seunghwan

    2006-06-01

    We propose an approach for analyzing the basic relation between correlation properties of the original signal and its magnitude fluctuations by decomposing the original signal into its positive and negative fluctuation components. We use this relation to understand the following phenomenon found in many naturally occurring time series: the magnitude of the signal exhibits long-range correlation, whereas the original signal is short-range correlated. The applications of our approach to heart rate variability signals and high-frequency foreign exchange rates reveal that the difference between the correlation properties of the original signal and its magnitude fluctuations is induced by the time organization structure of the correlation function between the magnitude fluctuations of positive and negative components. We show that this correlation function can be described well by a stretched-exponential function and is related to the nonlinearity and the multifractal structure of the signals.

  14. Functional traits can improve our understanding of niche- and dispersal-based processes.

    Science.gov (United States)

    Jiang, Feng; Xun, Yanhan; Cai, Huiying; Jin, Guangze

    2018-03-01

    Ecologists often determine the relative importance of niche- and dispersal-based processes via variation partitioning based on species composition. Functional traits and their proxies of phylogeny are expected to increase the detection of niche-based processes and reduce the unexplained variation relative to species identity. We collected eight adult tree traits and phylogenetic data of 41 species and employed a phylogenetic fuzzy weighting method to address this issue in a 9-ha temperate forest dynamics plot. We used redundancy analysis to relate species, phylogenetic and functional compositions to environmental (soil resources and topography) and spatial variables. We also performed multi-scaled analyses on spatial variables by adding environment as the covariates to determine if functional traits increase the detection of niche-based processes at broad scales. The functional traits and intraspecific variation of the wood density among ontogenetic stages could dramatically increase the detection of niche-based processes and reduce the unexplained variation relative to species identity. Phylogenetic and functional compositions were mainly driven by total soil P and elevation, while species composition was weakly affected by multiple environmental variables. After controlling for the environment, a larger amount of the compositional variations in seed mass and maximum height were explained by finer-scaled spatial variables, indicating that dispersal processes may be important at fine spatial scales. Our results suggested that considering functional traits and their intraspecific variations could improve our understanding of ecological processes and increase our ability to predict the responses of plants to environmental change.

  15. Understanding integrated care: a comprehensive conceptual framework based on the integrative functions of primary care

    Directory of Open Access Journals (Sweden)

    Pim P. Valentijn

    2013-03-01

    Full Text Available Introduction: Primary care has a central role in integrating care within a health system. However, conceptual ambiguity regarding integrated care hampers a systematic understanding. This paper proposes a conceptual framework that combines the concepts of primary care and integrated care, in order to understand the complexity of integrated care.Methods:  The search method involved a combination of electronic database searches, hand searches of reference lists (snowball method and contacting researchers in the field. The process of synthesizing the literature was iterative, to relate the concepts of primary care and integrated care. First, we identified the general principles of primary care and integrated care. Second, we connected the dimensions of integrated care and the principles of primary care. Finally, to improve content validity we held several meetings with researchers in the field to develop and refine our conceptual framework.Results: The conceptual framework combines the functions of primary care with the dimensions of integrated care. Person-focused and population-based care serve as guiding principles for achieving integration across the care continuum. Integration plays complementary roles on the micro (clinical integration, meso (professional and organisational integration and macro (system integration level. Functional and normative integration ensure connectivity between the levels.Discussion:  The presented conceptual framework is a first step to achieve a better understanding of the inter-relationships among the dimensions of integrated care from a primary care perspective.

  16. Understanding integrated care: a comprehensive conceptual framework based on the integrative functions of primary care.

    Science.gov (United States)

    Valentijn, Pim P; Schepman, Sanneke M; Opheij, Wilfrid; Bruijnzeels, Marc A

    2013-01-01

    Primary care has a central role in integrating care within a health system. However, conceptual ambiguity regarding integrated care hampers a systematic understanding. This paper proposes a conceptual framework that combines the concepts of primary care and integrated care, in order to understand the complexity of integrated care. The search method involved a combination of electronic database searches, hand searches of reference lists (snowball method) and contacting researchers in the field. The process of synthesizing the literature was iterative, to relate the concepts of primary care and integrated care. First, we identified the general principles of primary care and integrated care. Second, we connected the dimensions of integrated care and the principles of primary care. Finally, to improve content validity we held several meetings with researchers in the field to develop and refine our conceptual framework. The conceptual framework combines the functions of primary care with the dimensions of integrated care. Person-focused and population-based care serve as guiding principles for achieving integration across the care continuum. Integration plays complementary roles on the micro (clinical integration), meso (professional and organisational integration) and macro (system integration) level. Functional and normative integration ensure connectivity between the levels. The presented conceptual framework is a first step to achieve a better understanding of the inter-relationships among the dimensions of integrated care from a primary care perspective.

  17. A Proteogenomic Approach to Understanding MYC Function in Metastatic Medulloblastoma Tumors

    Science.gov (United States)

    Staal, Jerome A.; Pei, Yanxin; Rood, Brian R.

    2016-01-01

    Brain tumors are the leading cause of cancer-related deaths in children, and medulloblastoma is the most prevalent malignant childhood/pediatric brain tumor. Providing effective treatment for these cancers, with minimal damage to the still-developing brain, remains one of the greatest challenges faced by clinicians. Understanding the diverse events driving tumor formation, maintenance, progression, and recurrence is necessary for identifying novel targeted therapeutics and improving survival of patients with this disease. Genomic copy number alteration data, together with clinical studies, identifies c-MYC amplification as an important risk factor associated with the most aggressive forms of medulloblastoma with marked metastatic potential. Yet despite this, very little is known regarding the impact of such genomic abnormalities upon the functional biology of the tumor cell. We discuss here how recent advances in quantitative proteomic techniques are now providing new insights into the functional biology of these aggressive tumors, as illustrated by the use of proteomics to bridge the gap between the genotype and phenotype in the case of c-MYC-amplified/associated medulloblastoma. These integrated proteogenomic approaches now provide a new platform for understanding cancer biology by providing a functional context to frame genomic abnormalities. PMID:27775567

  18. A Proteogenomic Approach to Understanding MYC Function in Metastatic Medulloblastoma Tumors

    Directory of Open Access Journals (Sweden)

    Jerome A. Staal

    2016-10-01

    Full Text Available Brain tumors are the leading cause of cancer-related deaths in children, and medulloblastoma is the most prevalent malignant childhood/pediatric brain tumor. Providing effective treatment for these cancers, with minimal damage to the still-developing brain, remains one of the greatest challenges faced by clinicians. Understanding the diverse events driving tumor formation, maintenance, progression, and recurrence is necessary for identifying novel targeted therapeutics and improving survival of patients with this disease. Genomic copy number alteration data, together with clinical studies, identifies c-MYC amplification as an important risk factor associated with the most aggressive forms of medulloblastoma with marked metastatic potential. Yet despite this, very little is known regarding the impact of such genomic abnormalities upon the functional biology of the tumor cell. We discuss here how recent advances in quantitative proteomic techniques are now providing new insights into the functional biology of these aggressive tumors, as illustrated by the use of proteomics to bridge the gap between the genotype and phenotype in the case of c-MYC-amplified/associated medulloblastoma. These integrated proteogenomic approaches now provide a new platform for understanding cancer biology by providing a functional context to frame genomic abnormalities.

  19. Functional Diversity as a New Framework for Understanding the Ecology of an Emerging Generalist Pathogen.

    Science.gov (United States)

    Morris, Aaron; Guégan, Jean-François; Benbow, M Eric; Williamson, Heather; Small, Pamela L C; Quaye, Charles; Boakye, Daniel; Merritt, Richard W; Gozlan, Rodolphe E

    2016-09-01

    Emerging infectious disease outbreaks are increasingly suspected to be a consequence of human pressures exerted on natural ecosystems. Previously, host taxonomic communities have been used as indicators of infectious disease emergence, and the loss of their diversity has been implicated as a driver of increased presence. The mechanistic details in how such pathogen-host systems function, however, may not always be explained by taxonomic variation or loss. Here we used machine learning and methods based on Gower's dissimilarity to quantify metrics of invertebrate functional diversity, in addition to functional groups and their taxonomic diversity at sites endemic and non-endemic for the model generalist pathogen Mycobacterium ulcerans, the causative agent of Buruli ulcer. Changes in these metrics allowed the rapid categorisation of the ecological niche of the mycobacterium's hosts and the ability to relate specific host traits to its presence in aquatic ecosystems. We found that taxonomic diversity of hosts and overall functional diversity loss and evenness had no bearing on the mycobacterium's presence, or whether the site was in an endemic area. These findings, however, provide strong evidence that generalist environmentally persistent bacteria such as M. ulcerans can be associated with specific functional traits rather than taxonomic groups of organisms, increasing our understanding of emerging disease ecology and origin.

  20. Understanding the Functionality of Human Activity Hotspots from Their Scaling Pattern Using Trajectory Data

    Directory of Open Access Journals (Sweden)

    Tao Jia

    2017-11-01

    Full Text Available Human activity hotspots are the clusters of activity locations in space and time, and a better understanding of their functionality would be useful for urban land use planning and transportation. In this article, using trajectory data, we aim to infer the functionality of human activity hotspots from their scaling pattern in a reliable way. Specifically, a large number of stopping locations are extracted from trajectory data, which are then aggregated into activity hotspots. Activity hotspots are found to display scaling patterns in terms of the sublinear scaling relationships between the number of stopping locations and the number of points of interest (POIs, which indicates economies of scale of human interactions with urban land use. Importantly, this scaling pattern remains stable over time. This finding inspires us to devise an allometric ruler to identify the activity hotspots, whose functionality could be reliably estimated using the stopping locations. Thereafter, a novel Bayesian inference model is proposed to infer their urban functionality, which examines the spatial and temporal information of stopping locations covering 75 days. Experimental results suggest that the functionality of identified activity hotspots are reliably inferred by stopping locations, such as the railway station.

  1. Towards a Stochastic Predictive Understanding of Ecosystem Functioning and Resilience to Environmental Changes

    Science.gov (United States)

    Pappas, C.

    2017-12-01

    Terrestrial ecosystem processes respond differently to hydrometeorological variability across timescales, and so does our scientific understanding of the underlying mechanisms. Process-based modeling of ecosystem functioning is therefore challenging, especially when long-term predictions are envisioned. Here we analyze the statistical properties of hydrometeorological and ecosystem variability, i.e., the variability of ecosystem process related to vegetation carbon dynamics, from hourly to decadal timescales. 23 extra-tropical forest sites, covering different climatic zones and vegetation characteristics, are examined. Micrometeorological and reanalysis data of precipitation, air temperature, shortwave radiation and vapor pressure deficit are used to describe hydrometeorological variability. Ecosystem variability is quantified using long-term eddy covariance flux data of hourly net ecosystem exchange of CO2 between land surface and atmosphere, monthly remote sensing vegetation indices, annual tree-ring widths and above-ground biomass increment estimates. We find that across sites and timescales ecosystem variability is confined within a hydrometeorological envelope that describes the range of variability of the available resources, i.e., water and energy. Furthermore, ecosystem variability demonstrates long-term persistence, highlighting ecological memory and slow ecosystem recovery rates after disturbances. We derive an analytical model, combining deterministic harmonics and stochastic processes, that represents major mechanisms and uncertainties and mimics the observed pattern of hydrometeorological and ecosystem variability. This stochastic framework offers a parsimonious and mathematically tractable approach for modelling ecosystem functioning and for understanding its response and resilience to environmental changes. Furthermore, this framework reflects well the observed ecological memory, an inherent property of ecosystem functioning that is currently not

  2. Understanding Service Composition with Non-functional Properties Using Declarative Model-to-model Transformations

    Directory of Open Access Journals (Sweden)

    Max Mäuhlhäuser

    2011-01-01

    Full Text Available Developing applications comprising service composition is a complex task. Therefore, to lower the skill barrier for developers, it is important to describe the problem at hand on an abstract level and not to focus on implementation details. This can be done using declarative programming which allows to describe only the result of the problem (which is what the developer wants rather than the description of the implementation. We therefore use purely declarative model-to-model transformations written in a universal model transformation language which is capable of handling even non functional properties using optimization and mathematical programming. This makes it easier to understand and describe service composition and non-functional properties for the developer.

  3. Making Sense of Abstract Algebra: Exploring Secondary Teachers' Understandings of Inverse Functions in Relation to Its Group Structure

    Science.gov (United States)

    Wasserman, Nicholas H.

    2017-01-01

    This article draws on semi-structured, task-based interviews to explore secondary teachers' (N = 7) understandings of inverse functions in relation to abstract algebra. In particular, a concept map task is used to understand the degree to which participants, having recently taken an abstract algebra course, situated inverse functions within its…

  4. An attempt to understand kidney's protein handling function by comparing plasma and urine proteomes.

    Directory of Open Access Journals (Sweden)

    Lulu Jia

    Full Text Available BACKGROUND: With the help of proteomics technology, the human plasma and urine proteomes, which closely represent the protein compositions of the input and output of the kidney, respectively, have been profiled in much greater detail by different research teams. Many datasets have been accumulated to form "reference profiles" of the plasma and urine proteomes. Comparing these two proteomes may help us understand the protein handling aspect of kidney function in a way, however, which has been unavailable until the recent advances in proteomics technology. METHODOLOGY/PRINCIPAL FINDINGS: After removing secreted proteins downstream of the kidney, 2611 proteins in plasma and 1522 in urine were identified with high confidence and compared based on available proteomic data to generate three subproteomes, the plasma-only subproteome, the plasma-and-urine subproteome, and the urine-only subproteome, and they correspond to three groups of proteins that are handled in three different ways by the kidney. The available experimental molecular weights of the proteins in the three subproteomes were collected and analyzed. Since the functions of the overrepresented proteins in the plasma-and-urine subproteome are probably the major functions that can be routinely regulated by excretion from the kidney in physiological conditions, Gene Ontology term enrichment in the plasma-and-urine subproteome versus the whole plasma proteome was analyzed. Protease activity, calcium and growth factor binding proteins, and coagulation and immune response-related proteins were found to be enriched. CONCLUSION/SIGNIFICANCE: The comparison method described in this paper provides an illustration of a new approach for studying organ functions with a proteomics methodology. Because of its distinctive input (plasma and output (urine, it is reasonable to predict that the kidney will be the first organ whose functions are further elucidated by proteomic methods in the near future. It

  5. Towards an integrated understanding of how micro scale processes shape groundwater ecosystem functions.

    Science.gov (United States)

    Schmidt, Susanne I; Cuthbert, Mark O; Schwientek, Marc

    2017-08-15

    Micro scale processes are expected to have a fundamental role in shaping groundwater ecosystems and yet they remain poorly understood and under-researched. In part, this is due to the fact that sampling is rarely carried out at the scale at which microorganisms, and their grazers and predators, function and thus we lack essential information. While set within a larger scale framework in terms of geochemical features, supply with energy and nutrients, and exchange intensity and dynamics, the micro scale adds variability, by providing heterogeneous zones at the micro scale which enable a wider range of redox reactions. Here we outline how understanding micro scale processes better may lead to improved appreciation of the range of ecosystems functions taking place at all scales. Such processes are relied upon in bioremediation and we demonstrate that ecosystem modelling as well as engineering measures have to take into account, and use, understanding at the micro scale. We discuss the importance of integrating faunal processes and computational appraisals in research, in order to continue to secure sustainable water resources from groundwater. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Understanding the Functions of Long Non-Coding RNAs through Their Higher-Order Structures

    Directory of Open Access Journals (Sweden)

    Rui Li

    2016-05-01

    Full Text Available Although thousands of long non-coding RNAs (lncRNAs have been discovered in eukaryotes, very few molecular mechanisms have been characterized due to an insufficient understanding of lncRNA structure. Therefore, investigations of lncRNA structure and subsequent elucidation of the regulatory mechanisms are urgently needed. However, since lncRNA are high molecular weight molecules, which makes their crystallization difficult, obtaining information about their structure is extremely challenging, and the structures of only several lncRNAs have been determined so far. Here, we review the structure–function relationships of the widely studied lncRNAs found in the animal and plant kingdoms, focusing on the principles and applications of both in vitro and in vivo technologies for the study of RNA structures, including dimethyl sulfate-sequencing (DMS-seq, selective 2′-hydroxyl acylation analyzed by primer extension-sequencing (SHAPE-seq, parallel analysis of RNA structure (PARS, and fragmentation sequencing (FragSeq. The aim of this review is to provide a better understanding of lncRNA biological functions by studying them at the structural level.

  7. Consumer understanding and use of health claims: the case of functional foods.

    Science.gov (United States)

    Annunziata, Azzurra; Mariani, Angela; Vecchio, Riccardo

    2014-01-01

    As widely acknowledged functional foods (FFs) may contribute to improve human health due to the presence of specific components useful for their protective action against several diseases. However it is essential that consumers are able to comprehend and assess the properties of FFs health claims play a central role in helping consumers to select among food alternatives, beyond providing protection against unsupported or misleading statements about foods properties. At the same time health claims are the main marketing tool that the food industry could use to differentiate FFs from other products. Clearly, massive investments in research and development are necessary to enter the FF market segment, together with the possibility to protect innovation through patents. Current paper aims to examine factors influencing consumer understanding and use of food health claims on FFs, as well as providing several indications for developers, marketers and policy makers. After a brief review of the literature the results of a quantitative survey conducted online on 650 Italian consumers are presented. Results show that consumer use and understanding of health claims on FFs depend on different variables such as socio-demographic characteristics, knowledge and confidence with nutrition information but also wording and variables related specifically to the product. Furthermore, different segments with a diverse degree of use and understanding of health claims have been identified. Therefore, to boost market growth, more efforts are needed by policy makers and marketers to provide better information on nutrition and health aspects of FF using an approach capable to ensure truthful, significant and clear information. Finally some recent patents related to the FFs market with specific regard to components and/or functionality investigated in the current paper are reviewed.

  8. Understanding human thiol dioxygenase enzymes: structure to function, and biology to pathology.

    Science.gov (United States)

    Sarkar, Bibekananda; Kulharia, Mahesh; Mantha, Anil K

    2017-04-01

    Amino acid metabolism is a significant metabolic activity in humans, especially of sulphur-containing amino acids, methionine and cysteine (Cys). Cys is cytotoxic and neurotoxic in nature; hence, mammalian cells maintain a constant intracellular level of Cys. Metabolism of Cys is mainly regulated by two thiol dioxygenases: cysteine dioxygenase (CDO) and 2-aminoethanethiol dioxygenase (ADO). CDO and ADO are the only human thiol dioxygenases reported with a role in Cys metabolism and localized to mitochondria. This metabolic pathway is important in various human disorders, as it is responsible for the synthesis of antioxidant glutathione and is also for the synthesis of hypotaurine and taurine. CDO is the most extensively studied protein, whose high-resolution crystallographic structures have been solved. As compared to CDO, ADO is less studied, even though it has a key role in cysteamine metabolism. To further understand ADO's structure and function, the three-dimensional structures have been predicted from I-TASSER and SWISS-MODEL servers and validated with PROCHECK software. Structural superimposition approach using iPBA web server further confirmed near-identical structures (including active sites) for the predicted protein models of ADO as compared to CDO. In addition, protein-protein interaction and their association in patho-physiology are crucial in understanding protein functions. Both ADO and CDO interacting partner profiles have been presented using STRING database. In this study, we have predicted a 3D model structure for ADO and summarized the biological roles and the pathological consequences which are associated with the altered expression and functioning of ADO and CDO in case of cancer, neurodegenerative disorders and other human diseases. © 2017 The Authors. International Journal of Experimental Pathology © 2017 International Journal of Experimental Pathology.

  9. Understanding the bonding nature of uranyl ion and functionalized graphene: a theoretical study.

    Science.gov (United States)

    Wu, Qun-Yan; Lan, Jian-Hui; Wang, Cong-Zhi; Xiao, Cheng-Liang; Zhao, Yu-Liang; Wei, Yue-Zhou; Chai, Zhi-Fang; Shi, Wei-Qun

    2014-03-20

    Studying the bonding nature of uranyl ion and graphene oxide (GO) is very important for understanding the mechanism of the removal of uranium from radioactive wastewater with GO-based materials. We have optimized 22 complexes between uranyl ion and GO applying density functional theory (DFT) combined with quasi-relativistic small-core pseudopotentials. The studied oxygen-containing functional groups include hydroxyl, carboxyl, amido, and dimethylformamide. It is observed that the distances between uranium atoms and oxygen atoms of GO (U-OG) are shorter in the anionic GO complexes (uranyl/GO(-/2-)) compared to the neutral GO ones (uranyl/GO). The formation of hydrogen bonds in the uranyl/GO(-/2-) complexes can enhance the binding ability of anionic GO toward uranyl ions. Furthermore, the thermodynamic calculations show that the changes of the Gibbs free energies in solution are relatively more negative for complexation reactions concerning the hydroxyl and carboxyl functionalized anionic GO complexes. Therefore, both the geometries and thermodynamic energies indicate that the binding abilities of uranyl ions toward GO modified by hydroxyl and carboxyl groups are much stronger compared to those by amido and dimethylformamide groups. This study can provide insights for designing new nanomaterials that can efficiently remove radionuclides from radioactive wastewater.

  10. Understanding the complexities of functional ability in Alzheimer's disease: more than just basic and instrumental factors.

    Science.gov (United States)

    Kahle-Wrobleski, Kristin; Coley, Nicola; Lepage, Benoit; Cantet, Christelle; Vellas, Bruno; Andrieu, Sandrine

    2014-05-01

    Dementia of the Alzheimer's type (AD) is defined by both cognitive and functional decline; new criteria allow for identification of milder, non-functionally impaired patients. Understanding loss of autonomy in AD is essential, as later stages represent a significant burden and cost to patients, their families, and society. The purpose of the present analyses was to determine the factor structure of the Alzheimer's Disease Cooperative Study-Activities of Daily Living Scale (ADCS-ADL) in a cohort of AD patients. Baseline ADCS-ADL assessments of 734 AD patients from the PLASA study were included in an exploratory factor analysis (EFA). Because the ADCS-ADL was designed to assess change over time, change from baseline scores over 2 years were also analyzed using an EFA. Factorial solutions were evaluated based on cross-loading, non-loadings, and number of items per factor. Mean age at baseline was 79.3, mean MMSE was 19.8 and 73.3% of participants were female. Baseline data suggested a 4-factor solution that included factors for basic ADLs (BADLs), domestic/household activities, communication/engagement with the environment, and outside activities. The change scores EFA suggested a 2-factor solution of BADLs and instrumental ADLs (IADLs). Distinct factors of IADLs should be considered for further validation as areas of attention to catch early functional decline.

  11. Understanding multicellular function and disease with human tissue-specific networks

    Science.gov (United States)

    Greene, Casey S.; Krishnan, Arjun; Wong, Aaron K.; Ricciotti, Emanuela; Zelaya, Rene A.; Himmelstein, Daniel S.; Zhang, Ran; Hartmann, Boris M.; Zaslavsky, Elena; Sealfon, Stuart C.; Chasman, Daniel I.; FitzGerald, Garret A.; Dolinski, Kara; Grosser, Tilo; Troyanskaya, Olga G.

    2016-01-01

    Tissue and cell-type identity lie at the core of human physiology and disease. Understanding the genetic underpinnings of complex tissues and individual cell lineages is crucial for developing improved diagnostics and therapeutics. We present genome-wide functional interaction networks for 144 human tissues and cell types developed using a data-driven Bayesian methodology that integrates thousands of diverse experiments spanning tissue and disease states. Tissue-specific networks predict lineage-specific responses to perturbation, reveal genes’ changing functional roles across tissues, and illuminate disease-disease relationships. We introduce NetWAS, which combines genes with nominally significant GWAS p-values and tissue-specific networks to identify disease-gene associations more accurately than GWAS alone. Our webserver, GIANT, provides an interface to human tissue networks through multi-gene queries, network visualization, analysis tools including NetWAS, and downloadable networks. GIANT enables systematic exploration of the landscape of interacting genes that shape specialized cellular functions across more than one hundred human tissues and cell types. PMID:25915600

  12. Using Brain Oscillations and Corticospinal Excitability to Understand and Predict Post-Stroke Motor Function

    Directory of Open Access Journals (Sweden)

    Aurore Thibaut

    2017-05-01

    Full Text Available What determines motor recovery in stroke is still unknown and finding markers that could predict and improve stroke recovery is a challenge. In this study, we aimed at understanding the neural mechanisms of motor function recovery after stroke using neurophysiological markers by means of cortical excitability (transcranial magnetic stimulation—TMS and brain oscillations (electroencephalography—EEG. In this cross-sectional study, 55 subjects with chronic stroke (62 ± 14 yo, 17 women, 32 ± 42 months post-stroke were recruited in two sites. We analyzed TMS measures (i.e., motor threshold—MT—of the affected and unaffected sides and EEG variables (i.e., power spectrum in different frequency bands and different brain regions of the affected and unaffected hemispheres and their correlation with motor impairment as measured by Fugl-Meyer. Multiple univariate and multivariate linear regression analyses were performed to identify the predictors of good motor function. A significant interaction effect of MT in the affected hemisphere and power in beta bandwidth over the central region for both affected and unaffected hemispheres was found. We identified that motor function positively correlates with beta rhythm over the central region of the unaffected hemisphere, while it negatively correlates with beta rhythm in the affected hemisphere. Our results suggest that cortical activity in the affected and unaffected hemisphere measured by EEG provides new insights on the association between high-frequency rhythms and motor impairment, highlighting the role of an excess of beta in the affected central cortical region in poor motor function in stroke recovery.

  13. Using Sandia's Z Machine and Density Functional Theory Simulations to Understand Planetary Materials

    Science.gov (United States)

    Root, Seth

    2017-06-01

    The use of Z, NIF, and Omega have produced many breakthrough results in high pressure physics. One area that has greatly benefited from these facilities is the planetary sciences. The high pressure behavior of planetary materials has implications for numerous geophysical and planetary processes. The continuing discovery of exosolar super-Earths demonstrates the need for accurate equation of state data to better inform our models of their interior structures. Planetary collision processes, such as the moon-forming giant impact, require understanding planetary materials over a wide-range of pressures and temperatures. Using Z, we examined the shock compression response of some common planetary materials: MgO, Mg2SiO4, and Fe2O3 (hematite). We compare the experimental shock compression measurements with density functional theory (DFT) based quantum molecular dynamics (QMD) simulations. The combination of experiment and theory provides clearer understanding of planetary materials properties at extreme conditions. Sandia National Laboratories is a multi-mission laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  14. Metabolomics: An Essential Tool to Understand the Function of Peroxisome Proliferator–Activated Receptor Alpha

    Science.gov (United States)

    Montanez, Jessica E.; Peters, Jeffrey M.; Correll, Jared B.; Gonzalez, Frank J.; Patterson, Andrew D.

    2013-01-01

    The peroxisome proliferator–activated receptor (PPAR) family of nuclear hormone transcription factors (PPARα, PPARβ/δ, and PPARγ) is regulated by a wide array of ligands including natural and synthetic chemicals. PPARs have important roles in control of energy metabolism and are known to influence inflammation, differentiation, carcinogenesis, and chemical toxicity. As such, PPARs have been targeted as therapy for common disorders such as cancer, metabolic syndrome, obesity, and diabetes. The recent application of metabolomics, or the global, unbiased measurement of small molecules found in biofluids, or extracts from cells, tissues, or organisms, has advanced our understanding of the varied and important roles that the PPARs have in normal physiology as well as in pathophysiological processes. Continued development and refinement of analytical platforms, and the application of new bioinformatics strategies, have accelerated the widespread use of metabolomics and have allowed further integration of small molecules into systems biology. Recent studies using metabolomics to understand PPARα function, as well as to identify PPARα biomarkers associated with drug efficacy/toxicity and drug-induced liver injury, will be discussed. PMID:23197196

  15. Gait and Cognition: A Complementary Approach to Understanding Brain Function and the Risk of Falling

    Science.gov (United States)

    Montero-Odasso, Manuel; Verghese, Joe; Beauchet, Olivier; Hausdorff, Jeffrey M.

    2012-01-01

    Until recently, clinicians and researchers have performed gait assessments and cognitive assessments separately when evaluating older adults. Increasing evidence from clinical practice, epidemiological studies, and clinical trials shows that gait and cognition are inter-related in older adults. Quantifiable alterations in gait among older adults are associated with falls, dementia, and disability. At the same time, emerging evidence indicates that early disturbances in cognitive processes such as attention, executive function, and working memory are associated with slower gait and gait instability during single and dual-task testing, and that these cognitive disturbances assist in the prediction of future mobility loss, falls, and progression to dementia. This paper reviews the importance of the gait-cognition inter-relationship in aging and presents evidence that gait assessments can provide a window into the understanding of cognitive function and dysfunctions, and fall risk in older people in clinical practice. To this end, the benefits of dual-task gait assessments (e.g., walking while performing an attention-demanding task) as a marker of fall risk are summarized. Further, we also present a potential complementary approach for reducing the risk of falls by improving certain aspects of cognition through both non-pharmacological and pharmacological treatments. Untangling the relationship between early gait disturbances and early cognitive changes may be helpful for identifying older adults at higher risk of experiencing mobility decline, falls and the progression to dementia. PMID:23110433

  16. Gait and cognition: a complementary approach to understanding brain function and the risk of falling.

    Science.gov (United States)

    Montero-Odasso, Manuel; Verghese, Joe; Beauchet, Olivier; Hausdorff, Jeffrey M

    2012-11-01

    Until recently, clinicians and researchers have performed gait assessments and cognitive assessments separately when evaluating older adults, but increasing evidence from clinical practice, epidemiological studies, and clinical trials shows that gait and cognition are interrelated in older adults. Quantifiable alterations in gait in older adults are associated with falls, dementia, and disability. At the same time, emerging evidence indicates that early disturbances in cognitive processes such as attention, executive function, and working memory are associated with slower gait and gait instability during single- and dual-task testing and that these cognitive disturbances assist in the prediction of future mobility loss, falls, and progression to dementia. This article reviews the importance of the interrelationship between gait and cognition in aging and presents evidence that gait assessments can provide a window into the understanding of cognitive function and dysfunction and fall risk in older people in clinical practice. To this end, the benefits of dual-task gait assessments (e.g., walking while performing an attention-demanding task) as a marker of fall risk are summarized. A potential complementary approach for reducing the risk of falls by improving certain aspects of cognition through nonpharmacological and pharmacological treatments is also presented. Untangling the relationship between early gait disturbances and early cognitive changes may be helpful in identifying older adults at risk of experiencing mobility decline, falls, and progression to dementia. © 2012, Copyright the Authors Journal compilation © 2012, The American Geriatrics Society.

  17. Understanding the Role of Negative Emotions in Adult Learning and Achievement: A Social Functional Perspective

    Directory of Open Access Journals (Sweden)

    Anna D. Rowe

    2018-02-01

    Full Text Available The role of emotions in adult learning and achievement has received increasing attention in recent years. However, much of the emphasis has been on test anxiety, rather than the wider spectrum of negative emotions such as sadness, grief, boredom and anger. This paper reports findings of a qualitative study exploring the experience and functionality of negative emotions at university. Thirty-six academic staff and students from an Australian university were interviewed about emotional responses to a range of learning events. Data analysis was informed by a prototype approach to emotion research. Four categories of discrete negative emotions (anger, sadness, fear, boredom were considered by teachers and students to be especially salient in learning, with self-conscious emotions (guilt, embarrassment, shame mentioned by more students than staff. While negative emotions were frequently viewed as detrimental to motivation, performance and learning, they were also construed under some circumstances as beneficial. The findings are discussed in relation to the value of social functional approaches for a better understanding of the diverse roles of negative emotions in learning and achievement.

  18. Understanding the Role of Negative Emotions in Adult Learning and Achievement: A Social Functional Perspective.

    Science.gov (United States)

    Rowe, Anna D; Fitness, Julie

    2018-02-20

    The role of emotions in adult learning and achievement has received increasing attention in recent years. However, much of the emphasis has been on test anxiety, rather than the wider spectrum of negative emotions such as sadness, grief, boredom and anger. This paper reports findings of a qualitative study exploring the experience and functionality of negative emotions at university. Thirty-six academic staff and students from an Australian university were interviewed about emotional responses to a range of learning events. Data analysis was informed by a prototype approach to emotion research. Four categories of discrete negative emotions (anger, sadness, fear, boredom) were considered by teachers and students to be especially salient in learning, with self-conscious emotions (guilt, embarrassment, shame) mentioned by more students than staff. While negative emotions were frequently viewed as detrimental to motivation, performance and learning, they were also construed under some circumstances as beneficial. The findings are discussed in relation to the value of social functional approaches for a better understanding of the diverse roles of negative emotions in learning and achievement.

  19. Understanding recovery: changes in the relationships of the International Classification of Functioning (ICF) components over time.

    Science.gov (United States)

    Davis, A M; Perruccio, A V; Ibrahim, S; Hogg-Johnson, S; Wong, R; Badley, E M

    2012-12-01

    The International Classification of Functioning, Disability and Health framework describes human functioning through body structure and function, activity and participation in the context of a person's social and physical environment. This work tested the temporal relationships of these components. Our hypotheses were: 1) there would be associations among physical impairment, activity limitations and participation restrictions within time; 2) prior status of a component would be associated with future status; 3) prior status of one component would influence status of a second component (e.g. prior activity limitations would be associated with current participation restrictions); and, 4) the magnitude of the within time relationships of the components would vary over time. Participants from Canada with primary hip or knee joint replacement (n = 931), an intervention with predictable improvement in pain and disability, completed standardized outcome measures pre-surgery and five times in the first year post-surgery. These included physical impairment (pain), activity limitations and participation restrictions. ICF component relationships were evaluated cross-sectionally and longitudinally using path analysis adjusting for age, sex, BMI, hip vs. knee, low back pain and mood. All component scores improved significantly over time. The path coefficients supported the hypotheses in that both within and across time, physical impairment was associated with activity limitation and activity limitation was associated with participation restriction; prior status and change in a component were associated with current status in another component; and, the magnitude of the path coefficients varied over time with stronger associations among components to three months post surgery than later in recovery with the exception of the association between impairment and participation restrictions which was of similar magnitude at all times. This work enhances understanding of the

  20. Urban Ecological Stewardship: Understanding the Structure, Function and Network of Community-based Urban Land Management

    Directory of Open Access Journals (Sweden)

    Lindsay K. Campbell

    2008-01-01

    Full Text Available Urban environmental stewardship activities are on the rise in cities throughout the Northeast. Groups participating in stewardship activities range in age, size, and geography and represent an increasingly complex and dynamic arrangement of civil society, government and business sectors. To better understand the structure, function and network of these community-based urban land managers, an assessment was conducted in 2004 by the research subcommittee of the Urban Ecology Collaborative. The goal of the assessment was to better understand the role of stewardship organizations engaged in urban ecology initiatives in selected major cities in the Northeastern U.S.: Boston, New Haven, New York City, Pittsburgh, Baltimore, and Washington, D.C. A total of 135 active organizations participated in this assessment. Findings include the discovery of a dynamic social network operating within cities, and a reserve of social capital and expertise that could be better utilized. Although often not the primary land owner, stewardship groups take an increasingly significant responsibility for a wide range of land use types including street and riparian corridors, vacant lots, public parks and gardens, green roofs, etc. Responsibilities include the delivery of public programs as well as daily maintenance and fundraising support. While most of the environmental stewardship organizations operate on staffs of zero or fewer than ten, with small cohorts of community volunteers, there is a significant difference in the total amount of program funding. Nearly all respondents agree that committed resources are scarce and insufficient with stewards relying upon and potentially competing for individual donations, local foundations, and municipal support. This makes it a challenge for the groups to grow beyond their current capacity and to develop long-term programs critical to resource management and education. It also fragments groups, making it difficult for planners and

  1. Antipruritic Effect of Cold-induced and Transient Receptor Potential-agonist-induced Counter-irritation on Histaminergic Itch in Humans.

    Science.gov (United States)

    Andersen, Hjalte H; Melholt, Camilla; Hilborg, Sigurd D; Jerwiarz, Anne; Randers, Amalie; Simoni, Amalie; Elberling, Jesper; Arendt-Nielsen, Lars

    2017-01-04

    A frequent empirical observation is that cold-induced counter-irritation may attenuate itch. The aim of this randomized, single-blinded, exploratory study was to evaluate the counter-irritation effects of cold-stimulation and topical application of transient receptor potential TRPA1/M8-agonists (trans-cinnamaldehyde/L-menthol, respectively), on histamine-induced itch, wheals and neurogenic inflammation in 13 healthy volunteers. Histamine 1% was applied to the volar forearms using skin prick-test lancets. Recorded outcome-parameters were itch intensity, wheal reactions, and neurogenic inflammation (measured by laser-speckle perfusion-imaging). Homotopic thermal counter-irritation was performed with 6 temperatures, ranging from 4°C to 37°C, using a 3 × 3-cm thermal stimulator. Chemical "cold-like" counter-irritation was conducted with 40% L-menthol and 10% trans-cinnamaldehyde, while 5% doxepin was used as a positive antipruritic control/comparator. Cold counter-irritation stimuli from 4°C to 22°C inhibited itch in a stimulus-intensity-dependent manner (p cold-like" counter-irritation with both L-menthol and trans-cinnamaldehyde had antipruritic efficacy similar to doxepin (p Cold-induced counter-irritation had an inhibitory effect on histaminergic itch, suggesting that agonists of cold transduction receptors could be of potential antipruritic value.

  2. Jatropha curcas, a biofuel crop: functional genomics for understanding metabolic pathways and genetic improvement.

    Science.gov (United States)

    Maghuly, Fatemeh; Laimer, Margit

    2013-10-01

    Jatropha curcas is currently attracting much attention as an oilseed crop for biofuel, as Jatropha can grow under climate and soil conditions that are unsuitable for food production. However, little is known about Jatropha, and there are a number of challenges to be overcome. In fact, Jatropha has not really been domesticated; most of the Jatropha accessions are toxic, which renders the seedcake unsuitable for use as animal feed. The seeds of Jatropha contain high levels of polyunsaturated fatty acids, which negatively impact the biofuel quality. Fruiting of Jatropha is fairly continuous, thus increasing costs of harvesting. Therefore, before starting any improvement program using conventional or molecular breeding techniques, understanding gene function and the genome scale of Jatropha are prerequisites. This review presents currently available and relevant information on the latest technologies (genomics, transcriptomics, proteomics and metabolomics) to decipher important metabolic pathways within Jatropha, such as oil and toxin synthesis. Further, it discusses future directions for biotechnological approaches in Jatropha breeding and improvement. © 2013 The Authors. Biotechnology Journal published by Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Multilevel functional genomics data integration as a tool for understanding physiology: a network biology perspective.

    Science.gov (United States)

    Davidsen, Peter K; Turan, Nil; Egginton, Stuart; Falciani, Francesco

    2016-02-01

    The overall aim of physiological research is to understand how living systems function in an integrative manner. Consequently, the discipline of physiology has since its infancy attempted to link multiple levels of biological organization. Increasingly this has involved mathematical and computational approaches, typically to model a small number of components spanning several levels of biological organization. With the advent of "omics" technologies, which can characterize the molecular state of a cell or tissue (intended as the level of expression and/or activity of its molecular components), the number of molecular components we can quantify has increased exponentially. Paradoxically, the unprecedented amount of experimental data has made it more difficult to derive conceptual models underlying essential mechanisms regulating mammalian physiology. We present an overview of state-of-the-art methods currently used to identifying biological networks underlying genomewide responses. These are based on a data-driven approach that relies on advanced computational methods designed to "learn" biology from observational data. In this review, we illustrate an application of these computational methodologies using a case study integrating an in vivo model representing the transcriptional state of hypoxic skeletal muscle with a clinical study representing muscle wasting in chronic obstructive pulmonary disease patients. The broader application of these approaches to modeling multiple levels of biological data in the context of modern physiology is discussed. Copyright © 2016 the American Physiological Society.

  4. Complexities in Understanding Attentional Functioning among Children with Fetal Alcohol Spectrum Disorder

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    Kimberly eLane

    2014-03-01

    Full Text Available Parental reports of attention problems and clinical symptomatology of ADHD among children with fetal alcohol syndrome disorder (FASD were assessed in relation to performance on standardized subtests of attantional control/shifting and selective attention from the Test of Everyday Attention for Children (TEA-Ch; Manly et al., 1998. The participants included 14 children with FASD with a mean CA of 11.7 years and a mean MA of 9.7 years, and 14 typically developing (TD children with no reported history of prenatal exposure to alcohol or attention problems with a mean CA of 8.4 years and a mean MA of 9.6 years. The children with FASD were rated by their caregivers as having clinically significant attention difficulties for their developmental age. The reported symptomatology for the majority of the children with FASD were consistent with a diagnosis of ADHD, combined type, and only one child had a score within the average range. These reports are consistent with the finding here that the children with FASD demonstrated difficulties on the Creature Counting subtest of attentional control/shifting, but inconsistent with the finding that they outperformed the TD children on the Map Mission subtest of selective attention. These findings are considered within the context of the complexity in understanding attentional functioning among children with FASD and discrepancies across sources of information and components of attention.

  5. An Analysis of Grade 11 Learners' Levels of Understanding of Functions in Terms of APOS Theory

    Science.gov (United States)

    Chimhande, Tinoda; Naidoo, Ana; Stols, Gerrit

    2017-01-01

    This article reports on a study of six Grade 11 learners' levels of understanding of concepts related to the function definition and representation. Task-based clinical interviews were used to elicit the learners' interpretations and reasoning when working with these function-related concepts. Indicators for Action-Process-Object-Schema (APOS)…

  6. Understanding the Structure-Function Relationships of Dendrimers in Environmental and Biomedical Applications

    Science.gov (United States)

    Wang, Bo

    We are living an era wherein nanoparticles (NPs) have been widely applied in our lives. Dendrimers are special polymeric NPs with unique physiochemical properties, which have been intensely explored for a variety of applications. Current studies on dendrimers are bottlenecked by insufficient understandings of their structure and dynamic behaviors from a molecular level. With primarily computational approaches supplemented by many other experimental technics, this dissertation aims to establish structure-function relationships of dendrimers in environmental and biomedical applications. More specifically, it thoroughly investigates the interactions between dendrimers and different biomolecules including carbon-based NPs, metal-based NPs, and proteins/peptides. Those results not only provide profound knowledge for evaluating the impacts of dendrimers on environmental and biological systems but also facilitate designing next-generation functional polymeric nanomaterials. The dissertation is organized as following. Chapter 1 provides an overview of current progresses on dendrimer studies, where methodology of Discrete Molecular Dynamics (DMD), my major research tool, is also introduced. Two directions of utilizing dendrimers will be discussed in following chapters. Chapter 2 will focus on environmental applications of dendrimers, where two back-to-back studies are presented. I will start from describing some interesting observations from experiments i.e. dendrimers dispersed model oil molecules. Then, I will reveal why surface chemistries of dendrimers lead to different remediation efficiencies by computational modelings. Finally, I will demonstrate different scenarios of dendrimer-small molecules association. Chapter 3 is centered on dendrimers in the biomedical applications including two subtopics. In the first topic, we will discuss dendrimers as surfactants that modulating the interactions between proteins and NPs. Some fundamental concepts regarding to NPs

  7. A Functional Approach towards Understanding the Role of the Mitochondrial Respiratory Chain in an Endomycorrhizal Symbiosis

    Science.gov (United States)

    Mercy, Louis; Lucic-Mercy, Eva; Nogales, Amaia; Poghosyan, Areg; Schneider, Carolin; Arnholdt-Schmitt, Birgit

    2017-01-01

    Arbuscular mycorrhizal fungi (AMF) are crucial components of fertile soils, able to provide several ecosystem services for crop production. Current economic, social and legislative contexts should drive the so-called “second green revolution” by better exploiting these beneficial microorganisms. Many challenges still need to be overcome to better understand the mycorrhizal symbiosis, among which (i) the biotrophic nature of AMF, constraining their production, while (ii) phosphate acts as a limiting factor for the optimal mycorrhizal inoculum application and effectiveness. Organism fitness and adaptation to the changing environment can be driven by the modulation of mitochondrial respiratory chain, strongly connected to the phosphorus processing. Nevertheless, the role of the respiratory function in mycorrhiza remains largely unexplored. We hypothesized that the two mitochondrial respiratory chain components, alternative oxidase (AOX) and cytochrome oxidase (COX), are involved in specific mycorrhizal behavior. For this, a complex approach was developed. At the pre-symbiotic phase (axenic conditions), we studied phenotypic responses of Rhizoglomus irregulare spores with two AOX and COX inhibitors [respectively, salicylhydroxamic acid (SHAM) and potassium cyanide (KCN)] and two growth regulators (abscisic acid – ABA and gibberellic acid – Ga3). At the symbiotic phase, we analyzed phenotypic and transcriptomic (genes involved in respiration, transport, and fermentation) responses in Solanum tuberosum/Rhizoglomus irregulare biosystem (glasshouse conditions): we monitored the effects driven by ABA, and explored the modulations induced by SHAM and KCN under five phosphorus concentrations. KCN and SHAM inhibited in vitro spore germination while ABA and Ga3 induced differential spore germination and hyphal patterns. ABA promoted mycorrhizal colonization, strong arbuscule intensity and positive mycorrhizal growth dependency (MGD). In ABA treated plants, R. irregulare

  8. Predictive Understanding of Mountainous Watershed Hydro-Biogeochemical Function and Response to Perturbations

    Science.gov (United States)

    Hubbard, S. S.; Williams, K. H.; Agarwal, D.; Banfield, J. F.; Beller, H. R.; Bouskill, N.; Brodie, E.; Maxwell, R. M.; Nico, P. S.; Steefel, C. I.; Steltzer, H.; Tokunaga, T. K.; Wainwright, H. M.; Dwivedi, D.; Newcomer, M. E.

    2017-12-01

    Recognizing the societal importance, vulnerability and complexity of mountainous watersheds, the `Watershed Function' project is developing a predictive understanding of how mountainous watersheds retain and release downgradient water, nutrients, carbon, and metals. In particular, the project is exploring how early snowmelt, drought, floods and other disturbances will influence mountainous watershed dynamics at seasonal to decadal timescales. Located in the 300km2 East River headwater catchment of the Upper Colorado River Basin, the project is guided by several constructs. First, the project considers the integrated role of surface and subsurface flow and biogeochemical reactions - from bedrock to the top of the vegetative canopy, from terrestrial through aquatic compartments, and from summit to receiving waters. The project takes a system-of-systems perspective, focused on developing new methods to quantify the cumulative watershed hydrobiogeochemical response to perturbations based on information from select subsystems within the watershed, each having distinct vegetation-subsurface biogeochemical-hydrological characteristics. A `scale-adaptive' modeling capability, in development using adaptive mesh refinement methods, serves as the organizing framework for the SFA. The scale-adaptive approach is intended to permit simulation of system-within-systems behavior - and aggregation of that behavior - from genome through watershed scales. This presentation will describe several early project discoveries and advances made using experimental, observational and numerical approaches. Among others, examples may include:quantiying how seasonal hydrological perturbations drive biogeochemical responses across critical zone compartments, with a focus on N and C transformations; metagenomic documentation of the spatial variability in floodplain meander microbial ecology; 3D reactive transport simulations of couped hydrological-biogeochemical behavior in the hyporheic zone; and

  9. Building an Understanding of Functions: A Series of Activities for Pre-Calculus

    Science.gov (United States)

    Carducci, Olivia M.

    2008-01-01

    Building block toys can be used to illustrate various concepts connected with functions including graphs and rates of change of linear and exponential functions, piecewise functions, and composition of functions. Five brief activities suitable for a pre-calculus course are described.

  10. Integrating community assembly and biodiversity to better understand ecosystem function: the Community Assembly and the Functioning of Ecosystems (CAFE) approach.

    Science.gov (United States)

    Bannar-Martin, Katherine H; Kremer, Colin T; Ernest, S K Morgan; Leibold, Mathew A; Auge, Harald; Chase, Jonathan; Declerck, Steven A J; Eisenhauer, Nico; Harpole, Stanley; Hillebrand, Helmut; Isbell, Forest; Koffel, Thomas; Larsen, Stefano; Narwani, Anita; Petermann, Jana S; Roscher, Christiane; Cabral, Juliano Sarmento; Supp, Sarah R

    2018-02-01

    The research of a generation of ecologists was catalysed by the recognition that the number and identity of species in communities influences the functioning of ecosystems. The relationship between biodiversity and ecosystem functioning (BEF) is most often examined by controlling species richness and randomising community composition. In natural systems, biodiversity changes are often part of a bigger community assembly dynamic. Therefore, focusing on community assembly and the functioning of ecosystems (CAFE), by integrating both species richness and composition through species gains, losses and changes in abundance, will better reveal how community changes affect ecosystem function. We synthesise the BEF and CAFE perspectives using an ecological application of the Price equation, which partitions the contributions of richness and composition to function. Using empirical examples, we show how the CAFE approach reveals important contributions of composition to function. These examples show how changes in species richness and composition driven by environmental perturbations can work in concert or antagonistically to influence ecosystem function. Considering how communities change in an integrative fashion, rather than focusing on one axis of community structure at a time, will improve our ability to anticipate and predict changes in ecosystem function. © 2017 The Authors. Ecology Letters published by CNRS and John Wiley & Sons Ltd.

  11. Understanding the hydrological functioning of headwater streams using periodic observations of river flow state

    Science.gov (United States)

    Beaufort, Aurélien; Leblois, Etienne; Pella, Hervé; Datry, Thibault; Sauquet, Eric

    2017-04-01

    Due to their upstream position in river networks, many headwater streams (HS) experience recurrent flow cessation and/or drying events. They have many ecological values since they are located at the interface between terrestrial and aquatic ecosystems and contribute to good status of rivers (sediment flux, input of organic matter…). However, the understanding of HS remains limited because gauging stations are preferentially located along perennial rivers and, consequently, the proportion of intermittent rivers (IR) is highly underestimated. In France, the observation network ONDE ("Observatoire National Des Etiages", in French) was designed by ONEMA to complement discharge data from the conventional French River Flow Monitoring network (HYDRO) to better understand HS dynamics. ONDE provides visual observations of flow state at 3300 sites along river channels located throughout France since 2012. One observation is made every month between April and October and the frequency of observations may increase during drought period to 4 visits / month. One of the following flow states is assigned at each observation: "flowing", "no flow" or "dry". The objective of this work is to combine and valorize information from both networks in order to describe the hydrological functioning of headwater streams at a regional scale. A special attention is given to characterize spatial distribution and frequency of flow intermittence and to explore how flow intermittence patterns are related to environmental drivers. A first analyze of the ONDE network indicated that 35% of sites have shown that at least one zero-flow event between 2012 and 2016 against only 8% with the HYDRO database considering gauging stations as intermittent when the mean number of zero flows ≥ 5 days/year. The proportion of zero-flow events for 93 ONDE sites was higher than 50%. Conversely, no drying events were observed for 1680 sites (50 %) during the observation period. These dry events mainly occurs during

  12. Understanding the Pathophysiology of Spinocerebellar Ataxias through genetics, neurophysiology, structural and functional neuroimaging

    Directory of Open Access Journals (Sweden)

    Pramod Kumar Pal

    2015-12-01

    largely absent with additional activity in contralateral cortices and in thalami in patients with SCA1; increased thalamic function could be one of the causes for disinhibition of the motor cortex contributing to uncoordinated movements.Studies on larger cohort of each subtype of SCAs to validate the above findings, follow-up studies to determine the rate and nature of progression of neurodegeneration and evaluation of pre-symptomatic genetically confirmed SCAs will help understand the pathophysiology of the SCAs.

  13. Expression and function of nuclear receptor coregulators in brain : understanding the cell-specific effects of glucocorticoids

    NARCIS (Netherlands)

    Laan, Siem van der

    2008-01-01

    Currently, the raising awareness of the role of glucocorticoids in the onset of numerous (neuro)-pathologies constitutes the increasing necessity of understanding the mechanisms of action of glucocorticoids in bodily processes and brain functioning. Glucocorticoids mediate their effects by binding

  14. Symbolic Understanding of Pictures in Low-Functioning Children with Autism: The Effects of Iconicity and Naming

    Science.gov (United States)

    Hartley, Calum; Allen, Melissa L.

    2015-01-01

    This research investigated whether symbolic understanding of pictures in low-functioning children with autism is mediated by iconicity and language. In Experiment 1, participants were taught novel words paired with unfamiliar pictures that varied in iconicity (black-and-white line drawings, greyscale photographs, colour line drawings, colour…

  15. Understanding fungal functional biodiversity during the mitigation of environmentally dispersed pentachlorophenol in cork oak forest soils

    NARCIS (Netherlands)

    Varela, Adelia; Martins, Celso; Nunez, Oscar; Martins, Isabel; Houbraken, Jos A. M. P.; Martins, Tiago M.; Leitao, M. Cristina; McLellan, Iain; Vetter, Walter; Galceran, M. Teresa; Samson, Robert A.; Hursthouse, Andrew; Pereira, Cristina Silva

    Pentachlorophenol (PCP) is globally dispersed and contamination of soil with this biocide adversely affects its functional biodiversity, particularly of fungi – key colonizers. Their functional role as a community is poorly understood, although a few pathways have been already elucidated in pure

  16. Challenges in microbial ecology: building predictive understanding of community function and dynamics

    NARCIS (Netherlands)

    Widder, S.; Allen, R.J.; Pfeiffer, T.; Curtis, T.P.; Wiuf, C.; Sloan, W.T.; Cordero, O.X.; Brown, S.P.; Momeni, B.; Shou, W.; Kettle, H.; Flint, H.J.; Haas, A.F.; Laroche, B.; Kreft, J.U.; Rainey, P.B.; Freilich, S.; Schuster, S.; Milferstedt, K.; van der Meer, J.R.; Groβkopf, T.; Huisman, J.; Free, A.; Picioreanu, C.; Quince, C.; Klapper, I.; Labarthe, S.; Smets, B.F.; Wang, H; Soyer, O.S.

    2016-01-01

    The importance of microbial communities (MCs) cannot be overstated. MCs underpin the biogeochemical cycles of the earth’s soil, oceans and the atmosphere, and perform ecosystem functions that impact plants, animals and humans. Yet our ability to predict and manage the function of these highly

  17. Understanding and solving disorder in the substitution pattern of amino functionalized MIL-47(V)

    NARCIS (Netherlands)

    Heinen, J.; Dubbeldam, D.

    2016-01-01

    Electronic energies and elastic constants of four amino functionalized MIL-47(V) supercells were computed using plane wave density functional theory to determine the influence of the substituent positions on the organic linker. An inverse relationship between the ab initio energies and the elastic

  18. Group Theory of Wannier Functions Providing the Basis for a Deeper Understanding of Magnetism and Superconductivity

    Directory of Open Access Journals (Sweden)

    Ekkehard Krüger

    2015-05-01

    Full Text Available The paper presents the group theory of optimally-localized and symmetry-adapted Wannier functions in a crystal of any given space group G or magnetic group M. Provided that the calculated band structure of the considered material is given and that the symmetry of the Bloch functions at all of the points of symmetry in the Brillouin zone is known, the paper details whether or not the Bloch functions of particular energy bands can be unitarily transformed into optimally-localized Wannier functions symmetry-adapted to the space group G, to the magnetic group M or to a subgroup of G or M. In this context, the paper considers usual, as well as spin-dependent Wannier functions, the latter representing the most general definition of Wannier functions. The presented group theory is a review of the theory published by one of the authors (Ekkehard Krüger in several former papers and is independent of any physical model of magnetism or superconductivity. However, it is suggested to interpret the special symmetry of the optimally-localized Wannier functions in the framework of a nonadiabatic extension of the Heisenberg model, the nonadiabatic Heisenberg model. On the basis of the symmetry of the Wannier functions, this model of strongly-correlated localized electrons makes clear predictions of whether or not the system can possess superconducting or magnetic eigenstates.

  19. The Effect of the Use of Number Lines Representations on Student Understanding of Basic Function Concepts.

    Science.gov (United States)

    Olsen, James R.

    Researchers and educators are calling for increased use of technology and attention to function concepts in school mathematics. Students often have considerable difficulty gleaning pointwise and global information from Cartesian (R squared) representations of functions, whether they are hand- or machine-produced. Described here is an interactive…

  20. The meaning of isometries as function of a set of points and the process of understanding of geometric transformation

    OpenAIRE

    Thaqi, Xhevdet; Gimenez, Joaquim; Aljimi, Ekrem

    2015-01-01

    International audience; In this paper, we try to show that in the process of understanding of isometric transformations, the meaning of isometric transformations is characterized as a function of whole figure to whole figure, as a function of the parts of the figure to the correspondent parts of the figure, and as a function of the set of points of figure to set of points of the same or other figures. This perception of isometric transformation has been observed in an experimental study which...

  1. The molecular understanding of interfacial interactions of functionalized graphene and chitosan

    International Nuclear Information System (INIS)

    Zhang, Hong-ping; Luo, Xue-gang; Lin, Xiao-yan; Lu, Xiong; Tang, Youhong

    2016-01-01

    Graphical abstract: The type of the functional groups can be used to modulating interactions between graphene sheet and chitosan. - Highlights: • Investigate interfacial interactions between chitosan and functionalized graphene by DFT. • Observe covalent linkages between COOH-modified graphene and chitosan units. • Multi-functionalized graphene regulates the interfacial interactions with chitosan. • It is useful for guiding the preparation of graphene/chitosan composites. - Abstract: Graphene-reinforced chitosan scaffolds have been extensively studied for several years as promising hard tissue replacements. However, the interfacial interactions between graphene and chitosan are strongly related to the solubility, processability, and mechanical properties of graphene-reinforced chitosan (G–C) composites. The functionalization of graphene is regarded as the most effective way to improve the abovementioned properties of the G–C composite. In this study, the interfacial interactions between chitosan and functionalized graphene sheets with carboxylization (COOH-), amination (NH 2 -), and hydroxylation (OH-) groups were systematically studied at the electronic level using the method of ab initio simulations based on quantum mechanics theory and the observations were compared with reported experimental results. The covalent linkages between COOH-modified graphene and the chitosan units were demonstrated and the combination of multi-functionalization on graphene could regulate the interfacial interactions between graphene and the chitosan. The interfacial interactions between chitosan and properly functionalized graphene are critical for the preparation of G–C-based composites for tissue engineering scaffolds and other applications.

  2. Understanding integrated care: a comprehensive conceptual framework based on the integrative functions of primary care.

    NARCIS (Netherlands)

    Valentijn, P.P.; Schepman, S.M.; Opheij, W.; Bruijnzeels, M.A.

    2013-01-01

    Introduction: Primary care has a central role in integrating care within a health system. However, conceptual ambiguity regarding integrated care hampers a systematic understanding. This paper proposes a conceptual framework that combines the concepts of primary care and integrated care, in order to

  3. On the Axiomatization of Mathematical Understanding: Continuous Functions in the Transition to Topology

    Science.gov (United States)

    Cheshire, Daniel C.

    2017-01-01

    The introduction to general topology represents a challenging transition for students of advanced mathematics. It requires the generalization of their previous understanding of ideas from fields like geometry, linear algebra, and real or complex analysis to fit within a more abstract conceptual system. Students must adopt a new lexicon of…

  4. Metagenomics-enabled understanding of the functions and activities of microbial communities at ERSP field research

    Energy Technology Data Exchange (ETDEWEB)

    Tiedje, James M. [Michigan State Univ., East Lansing, MI (United States)

    2014-01-08

    The focus of our work is to better understand the bioremediation of uranium in the subsurface. To evaluate the natural occurring uranium-immobilizing bacterial populations, we have anaerobically enriched uranium contaminated soil sediments (FW107, FW102-2, and FW102-3) collected from ORNL iFRC site (S3 area).

  5. Understanding the Attitude-Action Gap: Functional Integration of Environmental Aspects in Car Purchase Intentions

    Science.gov (United States)

    Mairesse, Olivier; Macharis, Cathy; Lebeau, Kenneth; Turcksin, Laurence

    2012-01-01

    This study aims at understanding how a general positive attitude toward the environment results in a limited purchase of environmentally friendlier cars, often referred to as the attitude-action gap. In a first experiment 27 volunteers performed a judgment task on car purchase intention. Participants were asked to evaluate the probability of…

  6. On the role of patterns in understanding the functioning of soil-vegetation-atmosphere systems

    Science.gov (United States)

    In this paper, we review the role of patterns to improve our understanding of water, mass and energy exchange processes in soil-vegetation-atmosphere systems. We explore the main mechanisms that lead to the formation of patterns in these systems and discuss different approaches to characterizing and...

  7. Challenges in microbial ecology: Building predictive understanding of community function and dynamics

    DEFF Research Database (Denmark)

    Widder, Stefanie; Allen, Rosalind J.; Pfeiffer, Thomas

    2016-01-01

    The importance of microbial communities (MCs) cannot be overstated. MCs underpin the biogeochemical cycles of the earth's soil, oceans and the atmosphere, and perform ecosystem functions that impact plants, animals and humans. Yet our ability to predict and manage the function of these highly...... complex, dynamically changing communities is limited. Building predictive models that link MC composition to function is a key emerging challenge in microbial ecology. Here, we argue that addressing this challenge requires close coordination of experimental data collection and method development...

  8. Drosophila Malpighian Tubules: A Model for Understanding Kidney Development, Function, and Disease.

    Science.gov (United States)

    Gautam, Naveen Kumar; Verma, Puja; Tapadia, Madhu G

    The Malpighian tubules of insects are structurally simple but functionally important organs, and their integrity is important for the normal excretory process. They are functional analogs of human kidneys which are important physiological organs as they maintain water and electrolyte balance in the blood and simultaneously help the body to get rid of waste and toxic products after various metabolic activities. In addition, it receives early indications of insults to the body such as immune challenge and other toxic components and is essential for sustaining life. According to National Vital Statistics Reports 2016, renal dysfunction has been ranked as the ninth most abundant cause of death in the USA. This chapter provides detailed descriptions of Drosophila Malpighian tubule development, physiology, immune function and also presents evidences that Malpighian tubules can be used as a model organ system to address the fundamental questions in developmental and functional disorders of the kidney.

  9. Teachers' Understanding of the Role of Executive Functions in Mathematics Learning

    Science.gov (United States)

    Gilmore, Camilla; Cragg, Lucy

    2014-01-01

    Cognitive psychology research has suggested an important role for executive functions, the set of skills that monitor and control thought and action, in learning mathematics. However, there is currently little evidence about whether teachers are aware of the importance of these skills and, if so, how they come by this information. We conducted an online survey of teachers' views on the importance of a range of skills for mathematics learning. Teachers rated executive function skills, and in particular inhibition and shifting, to be important for mathematics. The value placed on executive function skills increased with increasing teaching experience. Most teachers reported that they were aware of these skills, although few knew the term “executive functions.” This awareness had come about through their teaching experience rather than from formal instruction. Researchers and teacher educators could do more to highlight the importance of these skills to trainee or new teachers. PMID:25674156

  10. Expanding our understanding of leaf functional syndromes in savanna systems: the role of plant growth form.

    Science.gov (United States)

    Rossatto, Davi Rodrigo; Franco, Augusto Cesar

    2017-04-01

    The assessment of leaf strategies has been a common theme in ecology, especially where multiple sources of environmental constraints (fire, seasonal drought, nutrient-poor soils) impose a strong selection pressure towards leaf functional diversity, leading to inevitable tradeoffs among leaf traits, and ultimately to niche segregation among coexisting species. As diversification on leaf functional strategies is dependent on integration at whole plant level, we hypothesized that regardless of phylogenetic relatedness, leaf trait functional syndromes in a multivariate space would be associated with the type of growth form. We measured traits related to leaf gas exchange, structure and nutrient status in 57 coexisting species encompassing all Angiosperms major clades, in a wide array of plant morphologies (trees, shrubs, sub-shrubs, herbs, grasses and palms) in a savanna of Central Brazil. Growth forms differed in mean values for the studied functional leaf traits. We extracted 4 groups of functional typologies: grasses (elevated leaf dark respiration, light-saturated photosynthesis on a leaf mass and area basis, lower values of leaf Ca and Mg), herbs (high values of SLA, leaf N and leaf Fe), palms (high values of stomatal conductance, leaf transpiration and leaf K) and woody eudicots (sub-shrubs, shrubs and trees; low SLA and high leaf Ca and Mg). Despite the large range of variation among species for each individual trait and the independent evolutionary trajectory of individual species, growth forms were strongly associated with particular leaf trait combinations, suggesting clear evolutionary constraints on leaf function for morphologically similar species in savanna ecosystems.

  11. Understanding the functions and relationships of the glymphatic system and meningeal lymphatics

    DEFF Research Database (Denmark)

    Louveau, Antoine; Plog, Benjamin A; Antila, Salli

    2017-01-01

    to the peripheral (CNS-draining) lymph nodes. We speculate on the relationship between the two systems and their malfunction that may underlie some neurological diseases. Although much remains to be investigated, these new discoveries have changed our understanding of mechanisms underlying CNS immune privilege...... and CNS drainage. Future studies should explore the communications between the glymphatic system and meningeal lymphatics in CNS disorders and develop new therapeutic modalities targeting these systems....

  12. Using Genetically Engineered Animal Models in the Postgenomic Era to Understand Gene Function in Alcoholism

    Science.gov (United States)

    Reilly, Matthew T.; Harris, R. Adron; Noronha, Antonio

    2012-01-01

    Over the last 50 years, researchers have made substantial progress in identifying genetic variations that underlie the complex phenotype of alcoholism. Not much is known, however, about how this genetic variation translates into altered biological function. Genetic animal models recapitulating specific characteristics of the human condition have helped elucidate gene function and the genetic basis of disease. In particular, major advances have come from the ability to manipulate genes through a variety of genetic technologies that provide an unprecedented capacity to determine gene function in the living organism and in alcohol-related behaviors. Even newer genetic-engineering technologies have given researchers the ability to control when and where a specific gene or mutation is activated or deleted, allowing investigators to narrow the role of the gene’s function to circumscribed neural pathways and across development. These technologies are important for all areas of neuroscience, and several public and private initiatives are making a new generation of genetic-engineering tools available to the scientific community at large. Finally, high-throughput “next-generation sequencing” technologies are set to rapidly increase knowledge of the genome, epigenome, and transcriptome, which, combined with genetically engineered mouse mutants, will enhance insight into biological function. All of these resources will provide deeper insight into the genetic basis of alcoholism. PMID:23134044

  13. Estimation of Time-Varying Coherence and Its Application in Understanding Brain Functional Connectivity

    Directory of Open Access Journals (Sweden)

    Cheng Liu

    2010-01-01

    Full Text Available Time-varying coherence is a powerful tool for revealing functional dynamics between different regions in the brain. In this paper, we address ways of estimating evolutionary spectrum and coherence using the general Cohen's class distributions. We show that the intimate connection between the Cohen's class-based spectra and the evolutionary spectra defined on the locally stationary time series can be linked by the kernel functions of the Cohen's class distributions. The time-varying spectra and coherence are further generalized with the Stockwell transform, a multiscale time-frequency representation. The Stockwell measures can be studied in the framework of the Cohen's class distributions with a generalized frequency-dependent kernel function. A magnetoencephalography study using the Stockwell coherence reveals an interesting temporal interaction between contralateral and ipsilateral motor cortices under the multisource interference task.

  14. Understanding Pervasive Language Impairment in Young Children: Exploring Patterns in Narrative Language and Functional Communication

    Science.gov (United States)

    Waters, Anna Jeddeloh

    2013-01-01

    Research has identified language impairment as a pervasive disability (Bishop & Edmundson, 1987; Greenhalgh & Strong, 2001). Classroom communication behaviors have a role in the maintenance of special education eligibility and functional communication difficulties for young children with language impairment. This paper reviews the…

  15. A Dyadic Approach to Understanding the Link Between Sexual Functioning and Sexual Satisfaction in Heterosexual Couples

    NARCIS (Netherlands)

    Pascoal, Patrícia M.; Byers, E. Sandra; Alvarez, Maria-João; Santos-Iglesias, Pablo; Nobre, Pedro J.; Pereira, Cicero Roberto; Laan, Ellen

    2017-01-01

    Researchers have demonstrated that several dimensions of sexual functioning (e.g., sexual desire, arousal, orgasm) are associated with the sexual satisfaction of individuals in a committed mixed-sex (male-female) relationship. We extended this research by comparing a dyadic model that included both

  16. Excisional Precision Matters: Understanding the Influence of Excisional Volume Loss on Renal Function After Partial Nephrectomy.

    Science.gov (United States)

    Dagenais, Julien; Maurice, Matthew J; Mouracade, Pascal; Kara, Onder; Malkoc, Ercan; Kaouk, Jihad H

    2017-08-01

    Renal function after partial nephrectomy (PN) may depend on modifiable factors including ischemia time, excision of healthy parenchyma (excisional volume loss, EVL), and reconstructive methods. We retrospectively reviewed our institutional robotic PN database to identify the predictors of glomerular filtration rate (GFR) preservation (GFR-P) at 3-12 mo postoperatively, during which GFR decline plateaus. Baseline clinical, sociodemographic, and radiologic characteristics were captured. Univariate and multivariate (MV) linear regression analyses were performed and marginal effects were employed to examine the relative effect of EVL on renal function. A total of 647 patients who underwent robotic PN had GFR data at a median follow-up of 6 mo. On MV models, EVL was significantly correlated with GFR-P following log transformation (p=0.001). Each doubling of EVL caused a 1.5% decrease in GFR-P. Ischemia time and tumor complexity were not significantly associated with GFR-P. In summary, GFR-P after PN appears to be significantly associated with the excised volume of benign parenchyma. At a high-volume tertiary care center, we investigated the impact of surgical factors on kidney function after kidney cancer surgery. We found that the surgical precision with which the tumor is excised significantly impacts kidney function at 3-12 mo after surgery. Copyright © 2017 European Association of Urology. Published by Elsevier B.V. All rights reserved.

  17. Quality of life and social production functions : A framework for understanding health effects

    NARCIS (Netherlands)

    Ormel, J.; Lindenberg, S.; Steverink, N.; Vonkorff, M.

    1997-01-01

    Quality of life (QofL) has emerged as a new outcome paradigm. It is now the endpoint in various taxonomies of patient outcomes, in which relationships are modeled amongst biological abnormalities, symptom status, functional status, disability, health perceptions and quality of life. Although current

  18. Phloem function: A key to understanding and manipulating plant responses to rising atmospheric [CO2]?

    Science.gov (United States)

    Increasing atmospheric carbon dioxide concentration ([CO2]) directly stimulates photosynthesis and reduces stomatal conductance in C3 plants. Both of these physiological effects have the potential to alter phloem function at elevated [CO2]. Recent research has clearly established that photosynthetic...

  19. Probability density of wave function of excited photoelectron: understanding XANES features

    Czech Academy of Sciences Publication Activity Database

    Šipr, Ondřej

    2001-01-01

    Roč. 8, - (2001), s. 232-234 ISSN 0909-0495 R&D Projects: GA ČR GA202/99/0404 Institutional research plan: CEZ:A02/98:Z1-010-914 Keywords : XANES * PED - probability density of wave function Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.519, year: 2001

  20. Towards understanding the evolution and functional diversification of DNA-containing plant organelles

    DEFF Research Database (Denmark)

    Leister, Dario Michael

    2016-01-01

    of plant nuclear genomes that have emerged since 2000. Here I review the results of these attempts to reconstruct the evolution and functions of plant DNA-containing organelles, focusing in particular on data from nuclear genomes. In addition, I discuss proteomic approaches to the direct identification...

  1. Teachers' Understanding of the Role of Executive Functions in Mathematics Learning

    Science.gov (United States)

    Gilmore, Camilla; Cragg, Lucy

    2014-01-01

    Cognitive psychology research has suggested an important role for executive functions, the set of skills that monitor and control thought and action, in learning mathematics. However, there is currently little evidence about whether teachers are aware of the importance of these skills and, if so, how they come by this information. We conducted an…

  2. Maternal yolk testosterone in canary eggs : toward a better understanding of mechanisms and function

    NARCIS (Netherlands)

    Muller, Wendt; Boonen, Sofie; Groothuis, Ton G. G.; Eens, Marcel

    2010-01-01

    Maternal yolk androgens in avian eggs have been shown to affect numerous offspring traits. These changes in offspring phenotype represent examples of maternal effects and are thought to adjust offspring development to the posthatching environment. When studying the functional consequences of yolk

  3. A Visualisation-Based Semiotic Analysis of Learners' Conceptual Understanding of Graphical Functional Relationships

    Science.gov (United States)

    Mudaly, Vimolan

    2014-01-01

    Within the South African school curriculum, the section on graphical functional relationships consists of signs which include symbols, notation and imagery. In a previous article we explored the role visualisation played in the way learners understood mathematical concepts. That paper reported on the learners' fixation with the physical features…

  4. Understanding the Emergence and Functioning of River Committees in a Catchment of the Pangani Basin, Tanzania

    Directory of Open Access Journals (Sweden)

    Hans C. Komakech

    2011-06-01

    To explain the difference in the performance of the three RCs we need to consider factors related to heterogeneity. We find that the functioning of RCs is strongly influenced by group size, spatial distance, heterogeneity of users and uses, and market forces.

  5. Understanding Parent-Child Social Informant Discrepancy in Youth with High Functioning Autism Spectrum Disorders

    Science.gov (United States)

    Lerner, Matthew D.; Calhoun, Casey D.; Mikami, Amori Yee; De Los Reyes, Andres

    2012-01-01

    We investigated discrepancies between parent- and self-reported social functioning among youth with autism spectrum disorders (ASD). Three distinct samples showed discrepancies indicating that parents viewed their children as performing one standard deviation below a standardization mean, while youth viewed themselves as comparably-skilled…

  6. Sharpening the edges of understanding the structure/function of the LPA1 receptor

    Science.gov (United States)

    Murph, Mandi; Nguyen, Giang; Radhakrishna, Harish; Mills, Gordon B.

    2008-01-01

    Since the molecular cloning of the vzg-1/Edg-2/LPA1 gene, studies have attempted to characterize LPA1 receptor functionality into a single categorical role, different from the other Edg-family LPA receptors. The desire to categorize LPA1 function has highlighted its complexity and demonstrated that the LPA1 receptor does not have one absolute function throughout every system. The central nervous system is highly enriched in the LPA1 receptor, suggesting an integral role in neuronal processes. Metastatic and invasive breast cancer also appears to have LPA-mediated LPA1 receptor functions that enhance phenotypes associated with tumorigenesis. LPA1 possesses a number of motifs conserved among G protein-coupled receptors (GPCRs): a DRY-like motif, a PDZ domain, Ser/Thr predicted sites of phosphorylation, a dileucine motif, double cysteines in the tail and conserved residues that stabilize structure and determine ligand binding. The third intracellular loop of the LPA1 receptor may be the crux of receptor signaling and attenuation with phosphorylation of Thr-236 potentially a key determinant of basal LPA1 signaling. Mutagenesis data supports the notion that Thr-236 regulates this process since mutating Thr-236 to Ala-236 increased basal and LPA-mediated serum response factor (SRF) signaling activity and Lys-236 further increased this basal signaling. Here we describe progress on defining the major functions of the LPA1 receptor, discuss a context dependent dualistic role as both a negative regulator in cancer and a proto-oncogene, outline its structural components at the molecular amino-acid level and present mutagenesis data on the third intracellular loop of the receptor. PMID:18501205

  7. Tool use ability depends on understanding of functional dynamics and not specific joint contribution profiles

    Directory of Open Access Journals (Sweden)

    Ross eParry

    2014-04-01

    Full Text Available Researchers in cognitive neuroscience have become increasingly interested in how different aspects of tool use are integrated and represented by the brain. Comparatively less attention has been directed towards tool use actions themselves and how effective tool use behaviors are coordinated. In response, we take this opportunity to consider the mechanical principles of tool use actions and their relationship to motor learning. Using kinematic analysis, we examine both functional dynamics and joint contribution profiles of subjects with different levels of experience in a primordial percussive task. Our results show that the ability to successfully produce stone flakes using the Oldowan method did not correspond with any particular joint contribution profile. Rather, expertise in this tool use action was principally associated with the subject’s ability to regulate the functional parameters that define the task itself.

  8. CHRONIC FUNCTIONAL CONSTIPATION IN CHILDREN — FROM UNDERSTANDING THE PROBLEM TO THE PROPER TREATMENT

    Directory of Open Access Journals (Sweden)

    V.F. Privorotskiy

    2010-01-01

    Full Text Available Functional origin is known in 95% of children with constipation. According to ICD-10 there is traditional distinction between syndrome of irritated bowel and proper functional constipation which have wide spectrum of causes. Rome criteria III propose initial diagnostic criteria of these disorders but the use of the criteria in pediatrics is frequently complicated. Clinical practice of pediatrician demands differentiation of constipations into hypertonic and hypotonic ones. Treatment programs include necessary component — laxative drugs which are useful in cases of subcompensated and decompensated types of constipation. One of the laxative drugs is Forlax containing polyethyleneglycol 4.000; it can be given to children 6 months old and older. The literature data shows high efficiency and safety of the drug.Key words: children, constipation, laxative drugs.(Voprosy sovremennoi pediatrii — Current Pediatrics. 2010;9(6:69-77

  9. How the mind understands other minds: cognitive psychology, attachment and reflective function.

    Science.gov (United States)

    Giannoni, Massimo; Corradi, Marina

    2006-04-01

    Jung's epistemological relativistic attitude was very advanced for his time and very much in line with the contemporary philosophy of science. Further, Jung states that the patient's unconscious has the capacity to represent itself by creating metaphors which give the therapist all the help he might need in treating his patient. As such, Jungian analysts have not been encouraged to embark on theoretical work and as a result, the Jungian movement has been lacking those theories that connect general psychological principles with clinical practices. In an attempt to enlarge our 'middle-range theories', we shall discuss Peter Fonagy's concept of reflective function. In our opinion, the theoretical hypothesis regarding the instinct of reading the mind (Baron-Cohen 1995) and Fonagy's idea of reflective function are extremely useful in our Jungian clinical practice and these concepts are utilizable because they are not at odds with analytical psychology's general epistemological and theoretical framework.

  10. Computerized Electroencephalogram. A model of understanding the brain function in childhood psychosis and its treatment.

    Science.gov (United States)

    Simeon, J; Itil, T M

    1975-09-01

    Computer analysis of the electroencephalogram (CEEG) in psychotic children before and after pharmacotherapy, normal children of schizophrenic mothers, and matched normal children of normal parents indicated significant intergroup differences. The psychotic children had more slow, as well as very fast, EEG waves. With drug therapy the EEG showed a partial "normalization," as fast EEG activity decreased. The EEG and auditory evoked potential of children of schizophrenic mothers were strikingly similar to those of psychotic children and schizophrenic adults, with significant decreases of the average EEG amplitude and the evoked potential latencies. Psychotic children were distinctly differentiated from the normal children by discriminant function analysis of the EEG and EP. Quantitative analysis of brain functions in the mentally ill can help determine the neurophysiological correlates of behavior, a more scientific diagnostic classification, prognosis, and selection of therapy.

  11. Analysis of Undergraduate Students’ Mathematical Understanding Ability of the Limit of Function Based on APOS Theory Perspective

    Science.gov (United States)

    Afgani, M. W.; Suryadi, D.; Dahlan, J. A.

    2017-09-01

    The aim of this study was to know the level of undergraduate students’ mathematical understanding ability based on APOS theory perspective. The APOS theory provides an evaluation framework to describe the level of students’ understanding and mental structure about their conception to a mathematics concept. The levels of understanding in APOS theory are action, process, object, and schema conception. The subjects were 59 students of mathematics education whom had attended a class of the limit of function at a university in Palembang. The method was qualitative descriptive with 4 test items. The result showed that most of students were still at the level of action conception. They could calculate and use procedure precisely to the mathematics objects that was given, but could not reach the higher conception yet.

  12. Predicting future forests: Understanding diverse phenological responses within a community and functional trait framework

    Science.gov (United States)

    Wolkovich, E. M.; Flynn, D. F. B.

    2016-12-01

    In recent years increasing attention has focused on plant phenology as an important indicator of the biological impacts of climate change, as many plants have shifted their leafing and flowering earlier with increasing temperatures. As data have accumulated, researchers have found a link between phenological responses to warming and plant performance and invasions. Such work suggests phenology may not only be a major impact of warming, but a critical predictor of future plant performance. Yet alongside this increasing interest in phenology, important issues remain unanswered: responses to warming for species at the same site or in the same genus vary often by weeks or more and the explanatory power of phenology for performance and invasions when analyzed across diverse datasets remains low. We propose progress can come from explicitly considering phenology within a community context and as a critical plant trait correlated with other major plant functional traits. Here, we lay out a framework for our proposal: specifically we review how we expect phenology and phenological cues of different species within a community to vary and what other functional traits are predicted to co-vary with phenological traits. Much research currently suggests phenology is a critical functional trait that is shaped strongly by the environment. Plants are expected to adjust their phenologies to avoid periods of high abiotic risk and/or high competition. Thus we may expect phenology to correlate strongly to other traits involved in mitigating risk and high competition. Results from recent meta-analyses as well as experimental and observational research from 28 species in northeastern North American temperate forests suggest that species within a community show the predicted diversified set of phenological cues. We review early work on links to other functional traits and in closing review how these correlations may in turn determine the diversity of phenological responses observed for

  13. Understanding right ventricular dysfunction and functional tricuspid regurgitation accompanying mitral valve disease.

    Science.gov (United States)

    Vargas Abello, Lina Maria; Klein, Allan L; Marwick, Thomas H; Nowicki, Edward R; Rajeswaran, Jeevanantham; Puwanant, Sarinya; Blackstone, Eugene H; Pettersson, Gösta B

    2013-05-01

    The study objective was to correlate the degree of tricuspid regurgitation with clinical indicators of right-sided heart failure and both qualitative and quantitative measures of right-sided heart morphology and function in patients with degenerative mitral valve disease. From 2001 to 2007, 1833 patients with degenerative mitral valve disease, structurally normal tricuspid valve, and no coronary artery disease underwent surgery. Right-sided heart morphology (right ventricular base-to-apex length, tethering distance and area, and right atrial systolic area) and right ventricular function (tricuspid annular plane systolic excursion, myocardial performance index, and tricuspid valve annular shortening) were measured on preoperative transthoracic echocardiograms for 100 randomly selected patients from each of tricuspid regurgitation grades 0, 1+, and 2+, and for all 93 patients with tricuspid regurgitation grade 3+/4+. Multivariable regression was used to evaluate the association of left- and right-sided heart morphology and function with tricuspid regurgitation. Increasing tricuspid regurgitation grade was associated with higher right ventricular pressure (P tricuspid regurgitation was present. When tricuspid regurgitation was 3+/4+, both tricuspid annular plane systolic excursion and myocardial performance index were almost certainly abnormal. Changes in right-sided heart morphology and right ventricular dysfunction were synergistic in relation to severity of tricuspid regurgitation. Functional tricuspid regurgitation accompanying mitral valve disease is associated with proportional changes in right-sided heart morphology; however, severe tricuspid regurgitation is nearly always associated with right ventricular dysfunction, suggesting a synergistic relationship. Right ventricular dysfunction is likely as important as tricuspid regurgitation because it offers an explanation for the negative prognostic impact of tricuspid regurgitation and has implications for the

  14. Understanding the Effects of Sleep Deprivation on Executive Function, Complex Task Performance and Situation Awareness

    OpenAIRE

    Grugle, Nancy Lynn

    2005-01-01

    Both sleep deprivation and loss of situation awareness (SA) have been cited as primary causal factors contributing to the accident and injury rate in the military and civilian sector (e.g., transportation). Despite the numerous references to both factors as causal in nature, much of the literature on the effects of sleep deprivation on executive function is anecdotal. Research has produced mixed results regarding the nature and extent of performance degradation on a variety of lower-level a...

  15. Understanding the value of plant diversity for ecosystem functioning through niche theory

    Science.gov (United States)

    Isbell, Forest; Purves, Drew W.; Loreau, Michel

    2016-01-01

    Biodiversity experiments have generated robust empirical results supporting the hypothesis that ecosystems function better when they contain more species. Given that ecosystems provide services that are valued by humans, this inevitably suggests that the loss of species from natural ecosystems could diminish their value. This raises two important questions. First, will experimental results translate into the real world, where species are being lost at an alarming rate? And second, what are the benefits and pitfalls of such valuation exercises? We argue that the empirical results obtained in experiments are entirely consistent with well-established theories of species coexistence. We then examine the current body of work through the lens of niche theory and highlight where closer links with theory could open up opportunities for future research. We argue that niche theory predicts that diversity–functioning relationships are likely to be stronger (and require more species) in the field than in simplified experimental settings. However, we caution that while many of the biological processes that promote coexistence can also generate diversity–function relationships, there is no simple mapping between the two. This implies that valuation exercises need to proceed with care. PMID:27928043

  16. Understanding the response of pulsed electric field on osteoblast functions in three-dimensional mesh structures.

    Science.gov (United States)

    Kumar, A; Nune, K C; Misra, Rdk

    2016-10-01

    The endogenous electric field plays a determining role in impacting biological functions including communication with the physiological system, brain, and bone regeneration by influencing cellular functions. From this perspective, the objective of the study described here is to elucidate the effect of external electric field under dynamic conditions, in providing a guiding cue to osteoblasts in terms of cell-cell interactions and synthesis of prominent adhesion and cytoskeleton proteins. This was accomplished using pulsed direct current electric field of strength 0.1-1 V/cm. The electric field provided guided cue to the cells to migrate toward cathode. Membrane blebbing or necrosis was nearly absent in the vicinity of cathode at 0.1 and 0.5 V/cm electric field strength. Moreover, a higher cell proliferation as well as higher expression of vinculin and densely packed actin stress fibers was observed. At anode, the cells though healthy but expression of actin and vinculin was less. We underscore for the first time that the biological functionality can be favorably modulated on 3D printed scaffolds in the presence of electric field and under dynamic conditions with consequent positive effect on cell proliferation, growth, and expression level of prominent proteins. © The Author(s) 2016.

  17. Mechanistic understanding of N-glycosylation in Ebola virus glycoprotein maturation and function.

    Science.gov (United States)

    Wang, Bin; Wang, Yujie; Frabutt, Dylan A; Zhang, Xihe; Yao, Xiaoyu; Hu, Dan; Zhang, Zhuo; Liu, Chaonan; Zheng, Shimin; Xiang, Shi-Hua; Zheng, Yong-Hui

    2017-04-07

    The Ebola virus (EBOV) trimeric envelope glycoprotein (GP) precursors are cleaved into the receptor-binding GP 1 and the fusion-mediating GP 2 subunits and incorporated into virions to initiate infection. GP 1 and GP 2 form heterodimers that have 15 or two N -glycosylation sites (NGSs), respectively. Here we investigated the mechanism of how N -glycosylation contributes to GP expression, maturation, and function. As reported before, we found that, although GP 1 NGSs are not critical, the two GP 2 NGSs, Asn 563 and Asn 618 , are essential for GP function. Further analysis uncovered that Asn 563 and Asn 618 regulate GP processing, demannosylation, oligomerization, and conformation. Consequently, these two NGSs are required for GP incorporation into EBOV-like particles and HIV type 1 (HIV-1) pseudovirions and determine viral transduction efficiency. Using CRISPR/Cas9 technology, we knocked out the two classical endoplasmic reticulum chaperones calnexin (CNX) and/or calreticulin (CRT) and found that both CNX and CRT increase GP expression. Nevertheless, NGSs are not required for the GP interaction with CNX or CRT. Together, we conclude that, although Asn 563 and Asn 618 are not required for EBOV GP expression, they synergistically regulate its maturation, which determines its functionality. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  18. Using analyses of amino Acid coevolution to understand protein structure and function.

    Science.gov (United States)

    Ashenberg, Orr; Laub, Michael T

    2013-01-01

    Determining which residues of a protein contribute to a specific function is a difficult problem. Analyses of amino acid covariation within a protein family can serve as a useful guide by identifying residues that are functionally coupled. Covariation analyses have been successfully used on several different protein families to identify residues that work together to promote folding, enable protein-protein interactions, or contribute to an enzymatic activity. Covariation is a statistical signal that can be measured in a multiple sequence alignment of homologous proteins. As sequence databases have expanded dramatically, covariation analyses have become easier and more powerful. In this chapter, we describe how functional covariation arises during the evolution of proteins and how this signal can be distinguished from various background signals. We discuss the basic methodology for performing amino acid covariation analysis, using bacterial two-component signal transduction proteins as an example. We provide practical suggestions for each step of the process including assembly of protein sequences, construction of a multiple sequence alignment, measurement of covariation, and analysis of results. Copyright © 2013 Elsevier Inc. All rights reserved.

  19. Understanding heterogeneity among elderly consumers: an evaluation of segmentation approaches in the functional food market.

    Science.gov (United States)

    van der Zanden, Lotte D T; van Kleef, Ellen; de Wijk, René A; van Trijp, Hans C M

    2014-06-01

    It is beneficial for both the public health community and the food industry to meet nutritional needs of elderly consumers through product formats that they want. The heterogeneity of the elderly market poses a challenge, however, and calls for market segmentation. Although many researchers have proposed ways to segment the elderly consumer population, the elderly food market has received surprisingly little attention in this respect. Therefore, the present paper reviewed eight potential segmentation bases on their appropriateness in the context of functional foods aimed at the elderly: cognitive age, life course, time perspective, demographics, general food beliefs, food choice motives, product attributes and benefits sought, and past purchase. Each of the segmentation bases had strengths as well as weaknesses regarding seven evaluation criteria. Given that both product design and communication are useful tools to increase the appeal of functional foods, we argue that elderly consumers in this market may best be segmented using a preference-based segmentation base that is predictive of behaviour (for example, attributes and benefits sought), combined with a characteristics-based segmentation base that describes consumer characteristics (for example, demographics). In the end, the effectiveness of (combinations of) segmentation bases for elderly consumers in the functional food market remains an empirical matter. We hope that the present review stimulates further empirical research that substantiates the ideas presented in this paper.

  20. Beyond localized and distributed accounts of brain functions. Comment on “Understanding brain networks and brain organization” by Pessoa

    Science.gov (United States)

    Cauda, Franco; Costa, Tommaso; Tamietto, Marco

    2014-09-01

    Recent evidence in cognitive neuroscience lends support to the idea that network models of brain architecture provide a privileged access to the understanding of the relation between brain organization and cognitive processes [1]. The core perspective holds that cognitive processes depend on the interactions among distributed neuronal populations and brain structures, and that the impact of a given region on behavior largely depends on its pattern of anatomical and functional connectivity [2,3].

  1. Beyond Self-Monitoring: Understanding Non-functional Aspects of Home-based Healthcare Technology

    DEFF Research Database (Denmark)

    Grönvall, Erik; Verdezoto, Nervo

    2013-01-01

    Monitoring of health parameters in non-clinical settings is one strategy to address the increasingly aging population and age-related disabilities and diseases. However, challenges exist when introducing self-monitoring activities in people’s everyday life. An active lifestyle can challenge......-technical complexities in home-based healthcare technologies through three case studies of self-monitoring: 1) pre-eclampsia (i.e. pregnancy poisoning), 2) heart conditions, and 3) preventive care. Through the analysis seven themes emerged (people, resources, places, routines, knowledge, control and motivation) that can...... facilitate the understanding of home-based healthcare activities. We present three modes of self-monitoring use and provide a set of design recommendations for future Ubicomp designs of home-based healthcare technology....

  2. Science Education initiation and the understanding of scientific phenomena: the function of non-formal activities

    Directory of Open Access Journals (Sweden)

    Rodrigo Dalcin

    2005-06-01

    Full Text Available Research evaluates the development of scientific initiation among Basic Level students as they are stimulated to experience cognitive processes in the production of knowledge. Such processes are a strategy to build significant knowledge. Informal teaching (non-formal and outside of the classroom activities contributes to education outside the borders of the classroom promoting experiments that allow greater development and creativity through an interactive type of learning. Carrying out research and presenting its results, make young scholars improve their communication skills as well as allows them to exchange and build new conceptions about scientific knowledge. Thus, they are able to acquire an integral vision and understanding of the world. Reality is unveiled through information, knowledge, technique and theory based on social demand rather than their imposition on society. Demand for knowledge and use of theory and practice have a dialectic relationship

  3. Understanding handpump sustainability: Determinants of rural water source functionality in the Greater Afram Plains region of Ghana.

    Science.gov (United States)

    Fisher, Michael B; Shields, Katherine F; Chan, Terence U; Christenson, Elizabeth; Cronk, Ryan D; Leker, Hannah; Samani, Destina; Apoya, Patrick; Lutz, Alexandra; Bartram, Jamie

    2015-10-01

    Safe drinking water is critical to human health and development. In rural sub-Saharan Africa, most improved water sources are boreholes with handpumps; studies suggest that up to one third of these handpumps are nonfunctional at any given time. This work presents findings from a secondary analysis of cross-sectional data from 1509 water sources in 570 communities in the rural Greater Afram Plains (GAP) region of Ghana; one of the largest studies of its kind. 79.4% of enumerated water sources were functional when visited; in multivariable regressions, functionality depended on source age, management, tariff collection, the number of other sources in the community, and the district. A Bayesian network (BN) model developed using the same data set found strong dependencies of functionality on implementer, pump type, management, and the availability of tools, with synergistic effects from management determinants on functionality, increasing the likelihood of a source being functional from a baseline of 72% to more than 97% with optimal management and available tools. We suggest that functionality may be a dynamic equilibrium between regular breakdowns and repairs, with management a key determinant of repair rate. Management variables may interact synergistically in ways better captured by BN analysis than by logistic regressions. These qualitative findings may prove generalizable beyond the study area, and may offer new approaches to understanding and increasing handpump functionality and safe water access.

  4. Understanding handpump sustainability: Determinants of rural water source functionality in the Greater Afram Plains region of Ghana

    Science.gov (United States)

    Fisher, Michael B.; Shields, Katherine F.; Chan, Terence U.; Christenson, Elizabeth; Cronk, Ryan D.; Leker, Hannah; Samani, Destina; Apoya, Patrick; Lutz, Alexandra; Bartram, Jamie

    2015-10-01

    Safe drinking water is critical to human health and development. In rural sub-Saharan Africa, most improved water sources are boreholes with handpumps; studies suggest that up to one third of these handpumps are nonfunctional at any given time. This work presents findings from a secondary analysis of cross-sectional data from 1509 water sources in 570 communities in the rural Greater Afram Plains (GAP) region of Ghana; one of the largest studies of its kind. 79.4% of enumerated water sources were functional when visited; in multivariable regressions, functionality depended on source age, management, tariff collection, the number of other sources in the community, and the district. A Bayesian network (BN) model developed using the same data set found strong dependencies of functionality on implementer, pump type, management, and the availability of tools, with synergistic effects from management determinants on functionality, increasing the likelihood of a source being functional from a baseline of 72% to more than 97% with optimal management and available tools. We suggest that functionality may be a dynamic equilibrium between regular breakdowns and repairs, with management a key determinant of repair rate. Management variables may interact synergistically in ways better captured by BN analysis than by logistic regressions. These qualitative findings may prove generalizable beyond the study area, and may offer new approaches to understanding and increasing handpump functionality and safe water access. This article was corrected on 11 Nov 2015. See the end of the full text for details.

  5. Receiver functions analysis in Northern Tanzania to understand the earliest stage of rifting

    Science.gov (United States)

    Tiberi, C.; Albaric, J.; Deschamps, A.; Deverchere, J.; Ebinger, C. J.; Ferdinand, R. W.; Gautier, S.; Lambert, C.; Msabi, M.; Mtelela, K.; Muzuka, A.; Perrot, J.; Rasendra, N.; Roecker, S. W.; Rodzianko, A.; Witkin, E.

    2013-12-01

    The East African Rift (EAR) is the site of stretching and breakup of the lithosphere in response to a combination of regional pulling forces and mantle upwellings. Deformation results from complex interactions between magmatic intrusions, faulting, asthenospheric dynamism and far field stresses. It thus involves both deep processes and local inherited fabrics. In the frame of two international projects CRAFTI (NSF) and CoLiBrEA (ANR), we gather our skills to lead a multidisciplinary project in order to characterize the factors involved in continental rifting. We target the first 5 My of a magmatic rift initiating in thick (>150 km) continental lithosphere, where we can directly image and detect fault and magma interactions, the role of inherited and rheological heterogeneities of the lithosphere on rift localisation. We deployed 35 broadband seismic stations in Natron and Ngorongoro areas in January 2013 to characterize crustal and mantle structures of the rift. The stations were equipped by 3 component sensors and Reftek Recorders to continuously record teleseisms as well as local seismicity. We present here a receiver function analyse on the teleseismic events recorded during the first 6 months of the experiment. Both P- and S-waves receiver functions were proceeded to document the modification of the crust and the mantle due to plate stretching and magmatic processes. The Vp/Vs ratio informs on the state of the crust, which is affected by magmatic and fluids intrusions at different depths. The S-wave receiver function gives insight into the lithosphere state and the nature of the mantle beneath the rift (archean or plume affected).

  6. Beyond form and functioning: Understanding how contextual factors influence village health committees in northern India.

    Science.gov (United States)

    Scott, Kerry; George, Asha S; Harvey, Steven A; Mondal, Shinjini; Patel, Gupteswar; Ved, Rajani; Garimella, Surekha; Sheikh, Kabir

    2017-01-01

    Health committees are a common strategy to foster community participation in health. Efforts to strengthen committees often focus on technical inputs to improve committee form (e.g. representative membership) and functioning (e.g. meeting procedures). However, porous and interconnected contextual spheres also mediate committee effectiveness. Using a framework for contextual analysis, we explored the contextual features that facilitated or hindered Village Health, Sanitation and Nutrition Committee (VHSNC) functionality in rural north India. We conducted interviews (n = 74), focus groups (n = 18) and observation over 1.5 years. Thematic content analysis enabled the identification and grouping of themes, and detailed exploration of sub-themes. While the intervention succeeded in strengthening committee form and functioning, participant accounts illuminated the different ways in which contextual influences impinged on VHSNC efficacy. Women and marginalized groups navigated social hierarchies that curtailed their ability to assert themselves in the presence of men and powerful local families. These dynamics were not static and unchanging, illustrated by pre-existing cross-caste problem solving, and the committee's creation of opportunities for the careful violation of social norms. Resource and capacity deficits in government services limited opportunities to build relationships between health system actors and committee members and engendered mistrust of government institutions. Fragmented administrative accountability left committee members bearing responsibility for improving local health without access to stakeholders who could support or respond to their efforts. The committee's narrow authority was at odds with widespread community needs, and committee members struggled to involve diverse government services across the health, sanitation, and nutrition sectors. Multiple parallel systems (political decentralization, media and other village groups) presented

  7. Beyond form and functioning: Understanding how contextual factors influence village health committees in northern India.

    Directory of Open Access Journals (Sweden)

    Kerry Scott

    Full Text Available Health committees are a common strategy to foster community participation in health. Efforts to strengthen committees often focus on technical inputs to improve committee form (e.g. representative membership and functioning (e.g. meeting procedures. However, porous and interconnected contextual spheres also mediate committee effectiveness. Using a framework for contextual analysis, we explored the contextual features that facilitated or hindered Village Health, Sanitation and Nutrition Committee (VHSNC functionality in rural north India. We conducted interviews (n = 74, focus groups (n = 18 and observation over 1.5 years. Thematic content analysis enabled the identification and grouping of themes, and detailed exploration of sub-themes. While the intervention succeeded in strengthening committee form and functioning, participant accounts illuminated the different ways in which contextual influences impinged on VHSNC efficacy. Women and marginalized groups navigated social hierarchies that curtailed their ability to assert themselves in the presence of men and powerful local families. These dynamics were not static and unchanging, illustrated by pre-existing cross-caste problem solving, and the committee's creation of opportunities for the careful violation of social norms. Resource and capacity deficits in government services limited opportunities to build relationships between health system actors and committee members and engendered mistrust of government institutions. Fragmented administrative accountability left committee members bearing responsibility for improving local health without access to stakeholders who could support or respond to their efforts. The committee's narrow authority was at odds with widespread community needs, and committee members struggled to involve diverse government services across the health, sanitation, and nutrition sectors. Multiple parallel systems (political decentralization, media and other village groups

  8. Understanding charge transfer of Li+ and Na+ ions scattered from metal surfaces with high work function

    International Nuclear Information System (INIS)

    Chen Lin; Wu Wen-Bin; Liu Pin-Yang; Xiao Yun-Qing; Li Guo-Peng; Liu Yi-Ran; Jiang Hao-Yu; Guo Yan-Ling; Chen Xi-Meng

    2016-01-01

    For Li + and Na + ions scattered from high work function metal surfaces, efficient neutralization is observed, and it cannot be explained by the conventional free electron model. In order to explain these experimental data, we investigate the velocity-dependent neutral fraction with the modified Brako–Newns (BN) model. The calculated results are in agreement with the experimental data. We find that the parallel velocity effect plays an important role in neutralizing the Li + and Na + ions for large angle scattering. The nonmonotonic velocity behavior of neutral fraction is strongly related to the distance-dependent coupling strength between the atomic level and metal states. (paper)

  9. Maximum Entropy Production As a Framework for Understanding How Living Systems Evolve, Organize and Function

    Science.gov (United States)

    Vallino, J. J.; Algar, C. K.; Huber, J. A.; Fernandez-Gonzalez, N.

    2014-12-01

    The maximum entropy production (MEP) principle holds that non equilibrium systems with sufficient degrees of freedom will likely be found in a state that maximizes entropy production or, analogously, maximizes potential energy destruction rate. The theory does not distinguish between abiotic or biotic systems; however, we will show that systems that can coordinate function over time and/or space can potentially dissipate more free energy than purely Markovian processes (such as fire or a rock rolling down a hill) that only maximize instantaneous entropy production. Biological systems have the ability to store useful information acquired via evolution and curated by natural selection in genomic sequences that allow them to execute temporal strategies and coordinate function over space. For example, circadian rhythms allow phototrophs to "predict" that sun light will return and can orchestrate metabolic machinery appropriately before sunrise, which not only gives them a competitive advantage, but also increases the total entropy production rate compared to systems that lack such anticipatory control. Similarly, coordination over space, such a quorum sensing in microbial biofilms, can increase acquisition of spatially distributed resources and free energy and thereby enhance entropy production. In this talk we will develop a modeling framework to describe microbial biogeochemistry based on the MEP conjecture constrained by information and resource availability. Results from model simulations will be compared to laboratory experiments to demonstrate the usefulness of the MEP approach.

  10. Understanding predictors of functional recovery and outcome 30 months following early childhood head injury.

    Science.gov (United States)

    Anderson, Vicki A; Catroppa, Cathy; Dudgeon, Paul; Morse, Sue A; Haritou, Flora; Rosenfeld, Jeffrey V

    2006-01-01

    Much is known about outcome following traumatic brain injury (TBI) in school-age children; however, recovery in early childhood is less well understood. Some argue that such injuries should lead to good outcome, because of the plasticity of the developing brain. Other purport that the young brain is vulnerable, with injury likely to result in a substantial impairment (H. G. Taylor & J. Alden, 1997). The aim of this study was to examine outcomes following TBI during early childhood, to plot recovery over the 30 months postinjury, and to identify predictors of outcome. The study compared 3 groups of children sustaining mild, moderate, and severe TBI, ages 2.0 to 6.11 years at injury, with healthy controls. Groups were comparable for preinjury adaptive and behavioral function, psychosocial characteristics, age, and gender. Results suggested a strong association between injury severity and outcomes across all domains. Further, 30-month outcome was predicted by injury severity, family factors, and preinjury levels of child function. In conclusion, children with more severe injuries and lower preinjury adaptive abilities, and whose families are coping poorly, are at greatest risk of long-term impairment in day-to-day skills, even several years postinjury.

  11. Molecular understanding of a potential functional link between antimicrobial and amyloid peptides.

    Science.gov (United States)

    Zhang, Mingzhen; Zhao, Jun; Zheng, Jie

    2014-10-14

    Antimicrobial and amyloid peptides do not share common sequences, typical secondary structures, or normal biological activity but both the classes of peptides exhibit membrane-disruption ability to induce cell toxicity. Different membrane-disruption mechanisms have been proposed for antimicrobial and amyloid peptides, individually, some of which are not exclusive to either peptide type, implying that certain common principles may govern the folding and functions of different cytolytic peptides and associated membrane disruption mechanisms. Particularly, some antimicrobial and amyloid peptides have been identified to have dual complementary amyloid and antimicrobial properties, suggesting a potential functional link between amyloid and antimicrobial peptides. Given that some similar structural and membrane-disruption characteristics exist between the two classes of peptides, this review summarizes major findings, recent advances, and future challenges related to antimicrobial and amyloid peptides and strives to illustrate the similarities, differences, and relationships in the sequences, structures, and membrane interaction modes between amyloid and antimicrobial peptides, with a special focus on direct interactions of the peptides with the membranes. We hope that this review will stimulate further research at the interface of antimicrobial and amyloid peptides - which has been studied less intensively than either type of peptides - to decipher a possible link between both amyloid pathology and antimicrobial activity, which can guide drug design and peptide engineering to influence peptide-membrane interactions important in human health and diseases.

  12. Incorporating modeling and simulations in undergraduate biophysical chemistry course to promote understanding of structure-dynamics-function relationships in proteins.

    Science.gov (United States)

    Hati, Sanchita; Bhattacharyya, Sudeep

    2016-01-01

    A project-based biophysical chemistry laboratory course, which is offered to the biochemistry and molecular biology majors in their senior year, is described. In this course, the classroom study of the structure-function of biomolecules is integrated with the discovery-guided laboratory study of these molecules using computer modeling and simulations. In particular, modern computational tools are employed to elucidate the relationship between structure, dynamics, and function in proteins. Computer-based laboratory protocols that we introduced in three modules allow students to visualize the secondary, super-secondary, and tertiary structures of proteins, analyze non-covalent interactions in protein-ligand complexes, develop three-dimensional structural models (homology model) for new protein sequences and evaluate their structural qualities, and study proteins' intrinsic dynamics to understand their functions. In the fourth module, students are assigned to an authentic research problem, where they apply their laboratory skills (acquired in modules 1-3) to answer conceptual biophysical questions. Through this process, students gain in-depth understanding of protein dynamics-the missing link between structure and function. Additionally, the requirement of term papers sharpens students' writing and communication skills. Finally, these projects result in new findings that are communicated in peer-reviewed journals. © 2016 The International Union of Biochemistry and Molecular Biology.

  13. Understanding the protective effects of wine components and their metabolites in the brain function

    Directory of Open Access Journals (Sweden)

    Esteban-Fernández A.

    2016-01-01

    Full Text Available Moderate wine consumption has been suggested to exert a positive effect in prevention of neurodegenerative process and cognitive impairment. With the ultimate aim of achieving a better understanding of the molecular mechanisms behind this benefit, we have investigated the role of certain wine- derived phenolic metabolites and aroma compounds in the MAPK cascade (including ERK1/2, p38, one of the routes directly related to inflammation in neuronal cells. Some of the tested phenolic compounds, especially in the case of 3,4-dihydroxyphenylacetic acid, showed a significant neuroprotective effect against SIN-1-induced neuronal death. Regarding their effect over MAPK phosphorylation, inmunoblotting technique revealed a beneficial and significant decrease on the phosphorylation of p38 and ERK1/2 kinases after incubation with wine constituents. In addition, activity of caspase3-like protease, an executor of neuronal apoptosis and a downstream signal of MAPK, was significantly diminished by 3-(3-hydroxyphenyl propionic acid and linalool, counterbalancing the increase produced by SIN-1. Altogether, these results suggest that wine aroma, phenolic compounds and their gut metabolites could exert neuroprotective actions by modulating MAPK signalling and caspase-3 proteases activation, which are known to play a key role in oxidative/ nitrosative stress-induced response.

  14. A dual-factor model of mental health: toward a more comprehensive understanding of youth functioning.

    Science.gov (United States)

    Antaramian, Susan P; Scott Huebner, E; Hills, Kimberly J; Valois, Robert F

    2010-10-01

    Traditional mental health models focus on psychological problems and distress; accordingly, health is viewed as the absence of illness or disability. In contrast, a dual-factor model of mental health incorporates both indicators of positive subjective well-being (SWB) and measures of psychopathological symptoms to comprehensively determine an individual's psychological adjustment. This study used such a dual-factor model to measure the mental health status of young adolescents. A total of 764 middle school students were classified into one of four distinct groups based on having high or low psychopathology and high or low SWB. Furthermore, group differences in student engagement, academic achievement, and environmental support for learning were investigated. Results demonstrated the existence of a traditionally neglected group of adolescents (low SWB and low psychopathology) who are nonetheless at risk for academic and behavior problems in school and who performed no better than the most troubled group of adolescents. Overall, both the presence of positive well-being and the absence of symptoms were necessary for ensuring the most advantageous school performance. These results highlight the importance of incorporating positive indicators of well-being along with traditional negative factors in more fully understanding relationships between individuals' mental health and educational outcomes. © 2010 American Orthopsychiatric Association.

  15. Understanding the Impact of Preservation Methods on the Integrity and Functionality of Placental Allografts.

    Science.gov (United States)

    Johnson, Amy; Gyurdieva, Alexandra; Dhall, Sandeep; Danilkovitch, Alla; Duan-Arnold, Yi

    2017-08-01

    Human placental membranes (hPMs) have a long history in treating burns and wounds. The composition of hPMs includes structural matrix, growth factors, and neonatal cells, all of which contribute to their regenerative potential. However, most hPM products are devitalized after dehydration and irradiation. We compared the functionality of single-layer viable cryopreserved human amniotic membrane (vCHAM) with multilayer devitalized dehydrated human amnion/chorion membrane (dHACM) in wound-relevant models to determine the effect of different processing methods on hPMs. Viable cryopreserved human amniotic membrane and dHACM were compared with fresh hPM for structural integrity and viability. Viable cell persistence in vCHAM over time was evaluated in vitro and in vivo in a diabetic chronic wound mouse model. Proliferation of cells within fresh hPM and vCHAM was evaluated with bromodeoxyuridine and Ki-67 staining, and proliferation of isolated cells in culture was evaluated. Growth factor release over time and in vitro response to chronic wound stimuli (tumor necrosis factor α, lipopolysaccharide, and hypoxia) were used to compare the functionality of vCHAM and dHACM. The structure and thickness of fresh hPM were retained in vCHAM but were compromised in dHACM. Similar to fresh hPM, vCHAM contained viable cells, whereas dHACM did not. Cells in vCHAM remained viable after 4 and 7 days in culture and in an in vitro chronic wound environment and after 4 and 8 days in vivo after application to a mouse chronic wound. Staining for bromodeoxyuridine and Ki-67 did not reveal proliferative cells within fresh hPM and vCHAM. However, isolated cells proliferated in culture. Viable cryopreserved human amniotic membrane increased platelet-derived growth factor BB, hepatocyte growth factor, and epidermal growth factor levels over time and responded to chronic wound stimuli in vitro by significantly increasing levels of vascular endothelial growth factor and prostaglandin E2

  16. Knowledge-Based Functional-Symbol Understanding In Electronic Circuit Diagram Interpretation

    Science.gov (United States)

    Huang, C. L.; Tou, J. T.

    1986-03-01

    The AUTORED system is a computer-based system for automatic reading of electronic circuit diagrams, which was developed several years ago. This paper presents some of our new results in AUTORED research. The design of AUTORED consists of two major components: automatic interpretation of electronic diagrams, and organization of interpretation results into a knowledge base for CAD applications. An electronic circuit diagram may be segmented into three parts which are the graphical functional symbols, the connection line segments, and the denotations. New techniques for extracting symbols and denotations from the circuit diagram are presented in this paper. These techniques are designed for junction and corner extraction, line segment tracing and linking, line segment classification, connection-line segment removal and blocking, symbol locating and denotation character grouping. A knowledge base is developed to facilitate the tracing, template-matching, and categorization processes.

  17. Understanding reaction mechanisms in organic chemistry from catastrophe theory applied to the electron localization function topology.

    Science.gov (United States)

    Polo, Victor; Andres, Juan; Berski, Slawomir; Domingo, Luis R; Silvi, Bernard

    2008-08-07

    Thom's catastrophe theory applied to the evolution of the topology of the electron localization function (ELF) gradient field constitutes a way to rationalize the reorganization of electron pairing and a powerful tool for the unambiguous determination of the molecular mechanisms of a given chemical reaction. The identification of the turning points connecting the ELF structural stability domains along the reaction pathway allows a rigorous characterization of the sequence of electron pair rearrangements taking place during a chemical transformation, such as multiple bond forming/breaking processes, ring closure processes, creation/annihilation of lone pairs, transformations of C-C multiple bonds into single ones. The reaction mechanism of some relevant organic reactions: Diels-Alder, 1,3-dipolar cycloaddition and Cope rearrangement are reviewed to illustrate the potential of the present approach.

  18. Caenorhabditis elegans as a model for understanding ROS function in physiology and disease

    Directory of Open Access Journals (Sweden)

    Antonio Miranda-Vizuete

    2017-04-01

    Full Text Available ROS (reactive oxygen species are potentially damaging by-products of aerobic metabolism which, unchecked, can have detrimental effects on cell function. However, it is now widely accepted that, at physiological levels, certain ROS play important roles in cell signaling, acting as second messengers to regulate cell choices that contribute to the development, adaptation and survival of plants and animals. Despite important recent advances in the biochemical tools available to study redox-signaling, the molecular mechanisms underlying most of these responses remain poorly understood, particularly in multicellular organisms. As we will review here, C. elegans has emerged as a powerful animal model to elucidate these and other aspects of redox biology.

  19. Phasic firing in vasopressin cells: understanding its functional significance through computational models.

    Directory of Open Access Journals (Sweden)

    Duncan J MacGregor

    Full Text Available Vasopressin neurons, responding to input generated by osmotic pressure, use an intrinsic mechanism to shift from slow irregular firing to a distinct phasic pattern, consisting of long bursts and silences lasting tens of seconds. With increased input, bursts lengthen, eventually shifting to continuous firing. The phasic activity remains asynchronous across the cells and is not reflected in the population output signal. Here we have used a computational vasopressin neuron model to investigate the functional significance of the phasic firing pattern. We generated a concise model of the synaptic input driven spike firing mechanism that gives a close quantitative match to vasopressin neuron spike activity recorded in vivo, tested against endogenous activity and experimental interventions. The integrate-and-fire based model provides a simple physiological explanation of the phasic firing mechanism involving an activity-dependent slow depolarising afterpotential (DAP generated by a calcium-inactivated potassium leak current. This is modulated by the slower, opposing, action of activity-dependent dendritic dynorphin release, which inactivates the DAP, the opposing effects generating successive periods of bursting and silence. Model cells are not spontaneously active, but fire when perturbed by random perturbations mimicking synaptic input. We constructed one population of such phasic neurons, and another population of similar cells but which lacked the ability to fire phasically. We then studied how these two populations differed in the way that they encoded changes in afferent inputs. By comparison with the non-phasic population, the phasic population responds linearly to increases in tonic synaptic input. Non-phasic cells respond to transient elevations in synaptic input in a way that strongly depends on background activity levels, phasic cells in a way that is independent of background levels, and show a similar strong linearization of the response

  20. The contributions of mental state understanding and executive functioning to preschool-aged children's lie-telling.

    Science.gov (United States)

    Leduc, Karissa; Williams, Shanna; Gomez-Garibello, Carlos; Talwar, Victoria

    2017-06-01

    In this study, preschool-aged children's lie-telling behaviour was examined in relation to mental state understanding and executive functioning. Sixty-seven children aged between 25 and 43 months (M age in months  = 34.80, SD = 4.39) participated in a temptation resistance paradigm (TRP). Children completed emerging ToM tasks measuring the following mental states: (1) diverse beliefs, (2) diverse desires, and (3) knowledge access. Children also completed measures of inhibitory control and working memory. In total, 63 of the 67 children peeked at the toy during the TRP, and a total of 26 of those children denied their transgression to the research assistant. Inhibitory control and understanding of knowledge access predicted lie-telling behaviour. Results are discussed in relation to a developmental model of children's lie-telling behaviour. Statement of contribution What is already known on this subject? The relationship between lie-telling, executive functioning, and ToM has been established in older children (aged 4 and above). Inhibitory control plays a role in young children's lie-telling (aged 2-4). Children above 3 years of age have some understanding of mental states. What does this study add? Very young children (2-3-year-olds) also possess an understanding of mental states. Mental state understanding is related to 2-3-year-old children's lie-telling behaviours and may be more predictive than inhibitory control. While the results were not significant, this study is the first to look at the unique role of working memory in very young children's lie-telling. © 2016 The British Psychological Society.

  1. Understanding collaborative care implementation in the Department of Veterans Affairs: core functions and implementation challenges.

    Science.gov (United States)

    Lipschitz, Jessica M; Benzer, Justin K; Miller, Christopher; Easley, Siena R; Leyson, Jenniffer; Post, Edward P; Burgess, James F

    2017-10-10

    The collaborative care model is an evidence-based practice for treatment of depression in which designated care managers provide clinical services, often by telephone. However, the collaborative care model is infrequently adopted in the Department of Veterans Affairs (VA). Almost all VA medical centers have adopted a co-located or embedded approach to integrating mental health care for primary care patients. Some VA medical centers have also adopted a telephone-based collaborative care model where depression care managers support patient education, patient activation, and monitoring of adherence and progress over time. This study evaluated two research questions: (1) What does a dedicated care manager offer in addition to an embedded-only model? (2) What are the barriers to implementing a dedicated depression care manager? This study involved 15 qualitative, multi-disciplinary, key informant interviews at two VA medical centers where reimbursement options were the same- both with embedded mental health staff, but one with a depression care manager. Participant interviews were recorded and transcribed. Thematic analysis was used to identify descriptive and analytical themes. Findings suggested that some of the core functions of depression care management are provided as part of embedded-only mental health care. However, formal structural attention to care management may improve the reliability of care management functions, in particular monitoring of progress over time. Barriers to optimal implementation were identified at both sites. Themes from the care management site included finding assertive care managers to hire, cross-discipline integration and collaboration, and primary care provider burden. Themes from interviews at the embedded site included difficulty getting care management on leaders' agendas amidst competing priorities and logistics (staffing and space). Providers and administrators see depression care management as a valuable healthcare service that

  2. Progress in understanding the molecular oxygen paradox - function of mitochondrial reactive oxygen species in cell signaling.

    Science.gov (United States)

    Kuksal, Nidhi; Chalker, Julia; Mailloux, Ryan J

    2017-10-26

    The molecular oxygen (O2) paradox was coined to describe its essential nature and toxicity. The latter characteristic of O2 is associated with the formation of reactive oxygen species (ROS), which can damage structures vital for cellular function. Mammals are equipped with antioxidant systems to fend off the potentially damaging effects of ROS. However, under certain circumstances antioxidant systems can become overwhelmed leading to oxidative stress and damage. Over the past few decades, it has become evident that ROS, specifically H2O2, are integral signaling molecules complicating the previous logos that oxyradicals were unfortunate by-products of oxygen metabolism that indiscriminately damage cell structures. To avoid its potential toxicity whilst taking advantage of its signaling properties, it is vital for mitochondria to control ROS production and degradation. H2O2 elimination pathways are well characterized in mitochondria. However, less is known about how H2O2 production is controlled. The present review examines the importance of mitochondrial H2O2 in controlling various cellular programs and emerging evidence for how production is regulated. Recently published studies showing how mitochondrial H2O2 can be used as a secondary messenger will be discussed in detail. This will be followed with a description of how mitochondria use S-glutathionylation to control H2O2 production.

  3. Understanding charge transfer of Li+ and Na+ ions scattered from metal surfaces with high work function

    Science.gov (United States)

    Chen, Lin; Wu, Wen-Bin; Liu, Pin-Yang; Xiao, Yun-Qing; Li, Guo-Peng; Liu, Yi-Ran; Jiang, Hao-Yu; Guo, Yan-Ling; Chen, Xi-Meng

    2016-08-01

    For Li+ and Na+ ions scattered from high work function metal surfaces, efficient neutralization is observed, and it cannot be explained by the conventional free electron model. In order to explain these experimental data, we investigate the velocity-dependent neutral fraction with the modified Brako-Newns (BN) model. The calculated results are in agreement with the experimental data. We find that the parallel velocity effect plays an important role in neutralizing the Li+ and Na+ ions for large angle scattering. The nonmonotonic velocity behavior of neutral fraction is strongly related to the distance-dependent coupling strength between the atomic level and metal states. Project supported by the National Natural Science Foundation of China (Grant Nos. 11405078 and 11474140), the Fundamental Research Funds for the Central Universities, China (Grant Nos. lzujbky-2014-169 and lzujbky-2015-244), the Project sponsored by the Scientific Research Foundation for the Returned Overseas Chinese Scholars, the State Education Ministry, and the National Students’ Innovation and Entrepreneurship Training Program (Grant Nos. 201410730069 and 201510730078).

  4. Formation, function, and exhaustion of notochordal cytoplasmic vacuoles within intervertebral disc: current understanding and speculation.

    Science.gov (United States)

    Wang, Feng; Gao, Zeng-Xin; Cai, Feng; Sinkemani, Arjun; Xie, Zhi-Yang; Shi, Rui; Wei, Ji-Nan; Wu, Xiao-Tao

    2017-08-22

    Notochord nucleus pulposus cells are characteristic of containing abundant and giant cytoplasmic vacuoles. This review explores the embryonic formation, biological function, and postnatal exhaustion of notochord vacuoles, aiming to characterize the signal network transforming the vacuolated nucleus pulposus cells into the vacuole-less chondrocytic cells. Embryonically, the cytoplasmic vacuoles within vertebrate notochord originate from an evolutionarily conserved vacuolation process during neurulation, which may continue to provide mechanical and signal support in constructing a mammalian intervertebral disc. For full vacuolation, a vacuolating specification from dorsal organizer cells, synchronized convergent extension, well-structured notochord sheath, and sufficient post-Golgi trafficking in notochord cells are required. Postnatally, age-related and species-specific exhaustion of vacuolated nucleus pulposus cells could be potentiated by Fas- and Fas ligand-induced apoptosis, intolerance to mechanical stress and nutrient deficiency, vacuole-mediated proliferation check, and gradual de-vacuolation within the avascular and compression-loaded intervertebral disc. These results suggest that the notochord vacuoles are active and versatile organelles for both embryonic notochord and postnatal nucleus pulposus, and may provide novel information on intervertebral disc degeneration to guide cell-based regeneration.

  5. Toward a Comprehensive Understanding of Executive Cognitive Function in Implicit Racial Bias

    Science.gov (United States)

    Ito, Tiffany A.; Friedman, Naomi P.; Bartholow, Bruce D.; Correll, Joshua; Loersch, Chris; Altamirano, Lee J.; Miyake, Akira

    2014-01-01

    Although performance on laboratory-based implicit bias tasks often is interpreted strictly in terms of the strength of automatic associations, recent evidence suggests that such tasks are influenced by higher-order cognitive control processes, so-called executive functions (EFs). However, extant work in this area has been limited by failure to account for the unity and diversity of EFs, focus on only a single measure of bias and/or EF, and relatively small sample sizes. The current study sought to comprehensively model the relation between individual differences in EFs and the expression of racial bias in three commonly used laboratory measures. Participants (N=485) completed a battery of EF tasks (session 1) and three racial bias tasks (session 2), along with numerous individual difference questionnaires. The main findings were as follows: (1) measures of implicit bias were only weakly intercorrelated; (2) EF and estimates of automatic processes both predicted implicit bias and also interacted, such that the relation between automatic processes and bias expression was reduced at higher levels of EF; (3) specific facets of EF were differentially associated with overall task performance and controlled processing estimates across different bias tasks; (4) EF did not moderate associations between implicit and explicit measures of bias; and (5) external, but not internal, motivation to control prejudice depended on EF to reduce bias expression. Findings are discussed in terms of the importance of global and specific EF abilities in determining expression of implicit racial bias. PMID:25603372

  6. Overview of experimental progress on understanding photon strength functions with an emphasis of the Oslo method

    Science.gov (United States)

    Krticka, Milan

    2015-10-01

    The so-called Photon Strength Functions (PSFs) for different multipolarities are, together with the Nuclear Level Density (NLD) the key entities describing the statistical γ-decay of nucleus. It is well known that PSFs at energies above the threshold for particle emission are well described by the Lorentzian shape of the Giant Electric Dipole Resonance (GEDR). On the other hand, shapes of RSFs at the low-energy tail of GEDR are known rather poorly. Information on the PSFs at the GEDR tail can be obtained from several different experimental techniques. They will be summarized and the most important ones briefly introduced in this contribution. Special emphasis will be put on the so-called Oslo method which allows simultaneous extraction of the NLD and the PSFs from particle- γ coincidence measurements. This method has been used for determining the NLD and the PSFs in many nuclei in A ~ 45- 240 range during past years. Examples of the most interesting results obtained with this method will be shown. The results will be compared to information on the PSFs available from other experimental techniques. The strengths and the weaknesses of the method will be thoroughly discussed.

  7. Understanding How Space Travel Affects Blood Vessels: Arterial Remodeling and Functional Adaptations Induced by Microgravity

    Science.gov (United States)

    Delp, Michael; Vasques, Marilyn; Aquilina, Rudy (Technical Monitor)

    2002-01-01

    Ever rise quickly from the couch to get something from the kitchen and suddenly feel dizzy? With a low heart rate and relaxed muscles, the cardiovascular system does not immediately provide the resistance necessary to keep enough blood going to your head. Gravity wins, at least for a short time, before your heart and blood vessels can respond to the sudden change in position and correct the situation. Actually, the human cardiovascular system is quite well adapted to the constant gravitational force of the Earth. When standing, vessels in the legs constrict to prevent blood from collecting in the lower extremities. In the space environment, the usual head-to-foot blood pressure and tissue fluid gradients that exist during the upright posture on Earth are removed. The subsequent shift in fluids from the lower to the upper portions of the body triggers adaptations within the cardiovascular system to accommodate the new pressure and fluid gradients. In animal models that simulate microgravity, the vessels in the head become more robust while those in the lower limbs become thin and lax. Similar changes may also occur in humans during spaceflight and while these adaptations are appropriate for a microgravity environment, they can cause problems when the astronauts return to Earth or perhaps another planet. Astronauts often develop orthostatic intolerance which means they become dizzy or faint when standing upright. This dizziness can persist for a number of days making routine activities difficult. In an effort to understand the physiological details of these cardiovascular adaptations, Dr. Michael Delp at Texas A&M University, uses the rat as a model for his studies. For the experiment flown on STS-107, he will test the hypothesis that blood vessels in the rats' hindlimbs become thinner, weaker, and constrict less in response to pressure changes and to chemical signals when exposed to microgravity. In addition, he will test the hypothesis that arteries in the brain

  8. Understanding of emotional experience in autism: insights from the personal accounts of high-functioning children with autism.

    Science.gov (United States)

    Losh, Molly; Capps, Lisa

    2006-09-01

    In this study, the authors investigate emotional understanding in autism through a discourse analytic framework to provide a window into children's strategies for interpreting emotional versus nonemotional encounters and consider the implications for the mechanisms underlying emotional understanding in typical development. Accounts were analyzed for thematic content and discourse structure. Whereas high-functioning children with autism were able to discuss contextually appropriate accounts of simple emotions, their strategies for interpreting all types of emotional (but not nonemotional) experiences differed from those used by typically developing children. High-functioning children with autism were less inclined to organize their emotional accounts in personalized causal-explanatory frameworks and displayed a tendency to describe visually salient elements of experiences seldom observed among comparison children. Findings suggest that children with autism possess less coherent representations of emotional experiences and use alternative strategies for interpreting emotionally evocative encounters. Discussion focuses on the significance of these findings for informing the nature of emotional dysfunction in autism as well as implications for theories of emotional understanding in typical development.

  9. Understanding Zika Virus Stability and Developing a Chimeric Vaccine through Functional Analysis

    Directory of Open Access Journals (Sweden)

    Xuping Xie

    2017-02-01

    Full Text Available Compared with other flaviviruses, Zika virus (ZIKV is uniquely associated with congenital diseases in pregnant women. One recent study reported that (i ZIKV has higher thermostability than dengue virus (DENV [a flavivirus closely related to ZIKV], which might contribute to the disease outcome; (ii the higher thermostability of ZIKV could arise from an extended loop structure in domain III of the viral envelope (E protein and an extra hydrogen-bond interaction between E molecules (V. A. Kostyuchenko, E. X. Y. Lim, S. Zhang, G. Fibriansah, T.-S. Ng, J. S. G. Ooi, J. Shi, and S.-M. Lok, Nature 533:425–428, 2016, https://doi.org/10.1038/nature17994. Here we report the functional analysis of the structural information in the context of complete ZIKV and DENV-2 virions. Swapping the prM-E genes between ZIKV and DENV-2 switched the thermostability of the chimeric viruses, identifying the prM-E proteins as the major determinants for virion thermostability. Shortening the extended loop of the E protein by 1 amino acid was lethal for ZIKV assembly/release. Mutations (Q350I and T351V that abolished the extra hydrogen-bond interaction between the E proteins did not reduce ZIKV thermostability, indicating that the extra interaction does not increase the thermostability. Interestingly, mutant T351V was attenuated in A129 mice defective in type I interferon receptors, even though the virus retained the wild-type thermostability. Furthermore, we found that a chimeric ZIKV with the DENV-2 prM-E and a chimeric DENV-2 with the ZIKV prM-E were highly attenuated in A129 mice; these chimeric viruses were highly immunogenic and protective against DENV-2 and ZIKV challenge, respectively. These results indicate the potential of these chimeric viruses for vaccine development.

  10. Recombinant yeast as a functional tool for understanding bitterness and cucurbitacin biosynthesis in watermelon (Citrullus spp.).

    Science.gov (United States)

    Davidovich-Rikanati, Rachel; Shalev, Lior; Baranes, Nadine; Meir, Ayala; Itkin, Maxim; Cohen, Shahar; Zimbler, Kobi; Portnoy, Vitaly; Ebizuka, Yutaka; Shibuya, Masaaki; Burger, Yosef; Katzir, Nurit; Schaffer, Arthur A; Lewinsohn, Efraim; Tadmor, Ya'akov

    2015-01-01

    Cucurbitacins are a group of bitter-tasting oxygenated tetracyclic triterpenes that are produced in the family Cucurbitaceae and other plant families. The natural roles of cucurbitacins in plants are probably related to defence against pathogens and pests. Cucurbitadienol, a triterpene synthesized from oxidosqualene, is the first committed precursor to cucurbitacins produced by a specialized oxidosqualene cyclase termed cucurbitadienol synthase. We explored cucurbitacin accumulation in watermelon in relation to bitterness. Our findings show that cucurbitacins are accumulated in bitter-tasting watermelon, Citrullus lanatus var. citroides, as well as in their wild ancestor, C. colocynthis, but not in non-bitter commercial cultivars of sweet watermelon (C. lanatus var. lanatus). Molecular analysis of genes expressed in the roots of several watermelon accessions led to the isolation of three sequences (CcCDS1, CcCDS2 and ClCDS1), all displaying high similarity to the pumpkin CpCPQ, encoding a protein previously shown to possess cucurbitadienol synthase activity. We utilized the Saccharomyces cerevisiae strain BY4743, heterozygous for lanosterol synthase, to probe for possible encoded cucurbitadienol synthase activity of the expressed watermelon sequences. Functional expression of the two sequences isolated from C. colocynthis (CcCDS1 and CcCDS2) in yeast revealed that only CcCDS2 possessed cucurbitadienol synthase activity, while CcCDS1 did not display cucurbitadienol synthase activity in recombinant yeast. ClCDS1 isolated from C. lanatus var. lanatus is almost identical to CcCDS1. Our results imply that CcCDS2 plays a role in imparting bitterness to watermelon. Yeast has been an excellent diagnostic tool to determine the first committed step of cucurbitacin biosynthesis in watermelon. Copyright © 2014 John Wiley & Sons, Ltd.

  11. Mania secondary to focal brain lesions: implications for understanding the functional neuroanatomy of bipolar disorder.

    Science.gov (United States)

    Satzer, David; Bond, David J

    2016-05-01

    Approximately 3.5 million Americans will experience a manic episode during their lifetimes. The most common causes are psychiatric illnesses such as bipolar I disorder and schizoaffective disorder, but mania can also occur secondary to neurological illnesses, brain injury, or neurosurgical procedures. For this narrative review, we searched Medline for articles on the association of mania with stroke, brain tumors, traumatic brain injury, multiple sclerosis, neurodegenerative disorders, epilepsy, and neurosurgical interventions. We discuss the epidemiology, features, and treatment of these cases. We also review the anatomy of the lesions, in light of what is known about the neurobiology of bipolar disorder. The prevalence of mania in patients with brain lesions varies widely by condition, from brain areas. Right-sided lesions causing hypo-functionality or disconnection (e.g., stroke; neoplasms) and left-sided excitatory lesions (e.g., epileptogenic foci) are frequently observed. Secondary mania should be suspected in patients with neurological deficits, histories atypical for classic bipolar disorder, and first manic episodes after the age of 40 years. Treatment with antimanic medications, along with specific treatment for the underlying neurologic condition, is typically required. Typical lesion locations fit with current models of bipolar disorder, which implicate hyperactivity of left-hemisphere reward-processing brain areas and hypoactivity of bilateral prefrontal emotion-modulating regions. Lesion studies complement these models by suggesting that right-hemisphere limbic-brain hypoactivity, or a left/right imbalance, may be relevant to the pathophysiology of mania. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  12. A Foray into Fungal Ecology: Understanding Fungi and Their Functions Across Ecosystems

    Science.gov (United States)

    Francis, N.; Dunkirk, N. C.; Peay, K.

    2015-12-01

    Despite their incredible diversity and importance to terrestrial ecosystems, fungi are not included in a standard high school science curriculum. This past summer, however, my work for the Stanford EARTH High School Internship program introduced me to fungal ecology through experiments involving culturing, genomics and root dissections. The two fungal experiments I worked on had very different foci, both searching for answers to broad ecological questions of fungal function and physiology. The first, a symbiosis experiment, sought to determine if the partners of the nutrient exchange between pine trees and their fungal symbionts could choose one another. The second experiment, a dung fungal succession project, compared the genetic sequencing results of fungal extractions from dung versus fungal cultures from dung. My part in the symbiosis experiment involved dissection, weighing and encapsulation of root tissue samples characterized based on the root thickness and presence of ectomycorrhizal fungi. The dung fungi succession project required that I not only learn how to culture various genera of dung fungi but also learn how to extract DNA and RNA for sequencing from the fungal tissue. Although I primarily worked with dung fungi cultures and thereby learned about their unique physiologies, I also learned about the different types of genetic sequencing since the project compared sequences of cultured fungi versus Next Generation sequencing of all fungi present within a dung pellet. Through working on distinct fungal projects that reassess how information about fungi is known within the field of fungal ecology, I learned not only about the two experiments I worked on but also many past related experiments and inquiries through reading scientific papers. Thanks to my foray into fungal research, I now know not only the broader significance of fungi in ecological research but also how to design and conduct ecological experiments.

  13. Some aspects of executive functions as predictors of understanding textual mathematical tasks in students with mild intellectual disability

    Directory of Open Access Journals (Sweden)

    Japundža-Milisavljević Mirjana

    2016-01-01

    Full Text Available The most significant segment during the process of solving mathematical tasks is translation from mathematical to native language, in the basis o which, among others, are the following factors: resistance to distraction and forming adequate verbal strategies. The goal of this research is to evaluate the contribution of some aspects of executive functions in explaining the variance of solving illustrative mathematical tasks in students with mild intellectual disability. The sample consists of 90 students with mild intellectual disability aged from 12 to 16 (M=14.7; SD=1.6, of both sexes (44.4% boys and 55.6% girls. The Twenty questions test and the Stroop test were used to estimate the executive functions. Verbal problem tasks were used for the purpose of understanding mathematical language The obtained results show that the estimated aspects of executive functions are significant predictors of understanding mathematical language in students with intellectual disabilities. The strongest predictor is distraction resistance (p=0.01.

  14. From understanding cellular function to novel drug discovery: the role of planar patch-clamp array chip technology

    Directory of Open Access Journals (Sweden)

    Christophe ePy

    2011-10-01

    Full Text Available All excitable cell functions rely upon ion channels that are embedded in their plasma membrane. Perturbations of ion channel structure or function result in pathologies ranging from cardiac dysfunction to neurodegenerative disorders. Consequently, to understand the functions of excitable cells and to remedy their pathophysiology, it is important to understand the ion channel functions under various experimental conditions – including exposure to novel drug targets. Glass pipette patch-clamp is the state of the art technique to monitor the intrinsic and synaptic properties of neurons. However, this technique is labor-intensive and has low data throughput. Planar patch-clamp chips, integrated into automated systems, offer high throughputs but are limited to isolated cells from suspensions, resulting in questionable models of true physiological function, and are unsuitable for studies involving neuronal communication. Multi-electrode arrays (MEA, in contrast, have the ability to monitor network activity by measuring local field potentials from multiple extracellular sites, but specific ion channel activity is challenging to extract from these multiplexed signals. Here we describe a novel planar patch-clamp chip technology that enables the simultaneous high resolution electrophysiological interrogation of individual neurons at multiple sites in synaptically connected neuronal networks, thereby combining the advantages of MEA and patch-clamp techniques. Each neuron can be probed through an aperture that connects to a dedicated subterranean microfluidic channel. Neurons growing in networks are aligned to the apertures by physisorbed or chemisorbed chemical cues. In this review, we describe the design and fabrication process of these chips, the approach to the chemical patterning for cell placement, and present physiological data from cultured neuronal cells.

  15. The value of eutherian-marsupial comparisons for understanding the function of glucocorticoids in female mammal reproduction.

    Science.gov (United States)

    Fanson, Kerry V; Parrott, Marissa L

    2015-11-01

    This article is part of a Special Issue "SBN 2014". Chronic stress is known to inhibit female reproductive function. Consequently, it is often assumed that glucocorticoid (GC) concentrations should be negatively correlated with reproductive success because of the role they play in stress physiology. In contrast, a growing body of evidence indicates that GCs play an active role in promoting reproductive function. It is precisely because GCs are so integral to the entire process that disruptions to adrenal activity have negative consequences for reproduction. The goal of this paper is to draw attention to the increasing evidence showing that increases in adrenal activity are important for healthy female reproduction. Furthermore, we outline several hypotheses about the functional role(s) that GCs may play in mediating reproduction and argue that comparative studies between eutherian and marsupial mammals, which exhibit some pronounced differences in reproductive physiology, may be particularly useful for testing different hypotheses about the functional role of GCs in reproduction. Much of our current thinking about GCs and reproduction comes from research involving stress-induced levels of GCs and has led to broad assumptions about the effects of GCs on reproduction. Unfortunately, this has left a gaping hole in our knowledge about basal GC levels and how they may influence reproductive function, thereby preventing a broader understanding of adrenal physiology and obscuring potential solutions for reproductive dysfunction. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Histaminergic regulation of prolactin secretion

    DEFF Research Database (Denmark)

    Knigge, U P

    1990-01-01

    Histamine (HA), which acts as a neurotransmitter in the central nervous system, participates in the neuroendocrine regulation of prolactin (PRL) secretion. HA has a predominant stimulatory effect which is mediated via H2-receptors following central administration and via H1-receptors following...... systemic infusion of the amine. In addition, HA seems to exert a minor inhibitory effect on PRL secretion, an effect unmasked only during blockade of the receptor mediating the stimulatory effect. Following central administration the inhibitory effect is mediated via H1-receptors, while following systemic...... administration this effect is mediated via H2-receptors. In accordance with these findings, the H2-receptor antagonist cimetidine (CIM) has an inhibitory (following central administration) or stimulatory (following systemic administration) effect on PRL secretion. However, high doses of CIM possess an additional...

  17. Tool-use training in a species of rodent: the emergence of an optimal motor strategy and functional understanding.

    Directory of Open Access Journals (Sweden)

    Kazuo Okanoya

    Full Text Available BACKGROUND: Tool use is defined as the manipulation of an inanimate object to change the position or form of a separate object. The expansion of cognitive niches and tool-use capabilities probably stimulated each other in hominid evolution. To understand the causes of cognitive expansion in humans, we need to know the behavioral and neural basis of tool use. Although a wide range of animals exhibit tool use in nature, most studies have focused on primates and birds on behavioral or psychological levels and did not directly address questions of which neural modifications contributed to the emergence of tool use. To investigate such questions, an animal model suitable for cellular and molecular manipulations is needed. METHODOLOGY/PRINCIPAL FINDINGS: We demonstrated for the first time that rodents can be trained to use tools. Through a step-by-step training procedure, we trained degus (Octodon degus to use a rake-like tool with their forelimbs to retrieve otherwise out-of-reach rewards. Eventually, they mastered effective use of the tool, moving it in an elegant trajectory. After the degus were well trained, probe tests that examined whether they showed functional understanding of the tool were performed. Degus did not hesitate to use tools of different size, colors, and shapes, but were reluctant to use the tool with a raised nonfunctional blade. Thus, degus understood the functional and physical properties of the tool after extensive training. CONCLUSIONS/SIGNIFICANCE: Our findings suggest that tool use is not a specific faculty resulting from higher intelligence, but is a specific combination of more general cognitive faculties. Studying the brains and behaviors of trained rodents can provide insights into how higher cognitive functions might be broken down into more general faculties, and also what cellular and molecular mechanisms are involved in the emergence of such cognitive functions.

  18. Chiropractic physicians: toward a select conceptual understanding of bureaucratic structures and functions in the health care institution.

    Science.gov (United States)

    Fredericks, Marcel; Kondellas, Bill; Hang, Lam; Fredericks, Janet; Ross, Michael Wv

    2011-12-01

    The purpose of this article is to present select concepts and theories of bureaucratic structures and functions so that chiropractic physicians and other health care professionals can use them in their respective practices. The society-culture-personality model can be applied as an organizational instrument for assisting chiropractors in the diagnosis and treatment of their patients irrespective of locality. Society-culture-personality and social meaningful interaction are examined in relationship to the structural and functional aspects of bureaucracy within the health care institution of a society. Implicit in the examination of the health care bureaucratic structures and functions of a society is the focus that chiropractic physicians and chiropractic students learn how to integrate, synthesize, and actualize values and virtues such as empathy, integrity, excellence, diversity, compassion, caring, and understanding with a deep commitment to self-reflection. It is essential that future and current chiropractic physicians be aware of the structural and functional aspects of an organization so that chiropractic and other health care professionals are able to deliver care that involves the ingredients of quality, affordability, availability, accessibility, and continuity for their patients.

  19. Chiropractic physicians: toward a select conceptual understanding of bureaucratic structures and functions in the health care institution

    Science.gov (United States)

    Fredericks, Marcel; Kondellas, Bill; Hang, Lam; Fredericks, Janet; Ross, Michael WV

    2011-01-01

    Objective The purpose of this article is to present select concepts and theories of bureaucratic structures and functions so that chiropractic physicians and other health care professionals can use them in their respective practices. The society-culture-personality model can be applied as an organizational instrument for assisting chiropractors in the diagnosis and treatment of their patients irrespective of locality. Discussion Society-culture-personality and social meaningful interaction are examined in relationship to the structural and functional aspects of bureaucracy within the health care institution of a society. Implicit in the examination of the health care bureaucratic structures and functions of a society is the focus that chiropractic physicians and chiropractic students learn how to integrate, synthesize, and actualize values and virtues such as empathy, integrity, excellence, diversity, compassion, caring, and understanding with a deep commitment to self-reflection. Conclusion It is essential that future and current chiropractic physicians be aware of the structural and functional aspects of an organization so that chiropractic and other health care professionals are able to deliver care that involves the ingredients of quality, affordability, availability, accessibility, and continuity for their patients. PMID:22693481

  20. PaGenBase: a pattern gene database for the global and dynamic understanding of gene function.

    Directory of Open Access Journals (Sweden)

    Jian-Bo Pan

    Full Text Available Pattern genes are a group of genes that have a modularized expression behavior under serial physiological conditions. The identification of pattern genes will provide a path toward a global and dynamic understanding of gene functions and their roles in particular biological processes or events, such as development and pathogenesis. In this study, we present PaGenBase, a novel repository for the collection of tissue- and time-specific pattern genes, including specific genes, selective genes, housekeeping genes and repressed genes. The PaGenBase database is now freely accessible at http://bioinf.xmu.edu.cn/PaGenBase/. In the current version (PaGenBase 1.0, the database contains 906,599 pattern genes derived from the literature or from data mining of more than 1,145,277 gene expression profiles in 1,062 distinct samples collected from 11 model organisms. Four statistical parameters were used to quantitatively evaluate the pattern genes. Moreover, three methods (quick search, advanced search and browse were designed for rapid and customized data retrieval. The potential applications of PaGenBase are also briefly described. In summary, PaGenBase will serve as a resource for the global and dynamic understanding of gene function and will facilitate high-level investigations in a variety of fields, including the study of development, pathogenesis and novel drug discovery.

  1. Alternative Conformational Model of a Seed Protein DeK1 for Better Understanding of Structure-Function Relationship

    Directory of Open Access Journals (Sweden)

    Surya Bhushan Kumar

    2010-12-01

    Full Text Available Understanding of the cell development and differentiation processes in plant seeds in general is poor. One gene, among others, that predominantly regulates the aleurone cell formation, differentiation and specification in seeds is called defective kernel (DeK1 and several cell biology and genetic experiments have unequivocally established this fact. However, the mechanism behind such processes is still unclear and understanding the protein functionality of DeK1 is vital to elucidating its role in endosperm cell development. Only preliminary investigations have been performed for just one domain of the protein in vitro and its functional implications have been highlighted lately. An initial attempt at in silico modeling of the protein has shown promise and necessitated thorough investigation of the protein to help understand structure-function relationship in details thus corroborating experimental findings and laying foundation for further studies. DeK1 sequences in public databases were used as raw material for elaborate computational analysis of the protein. DeK1 is a multi-pass membrane protein with interesting structural features and the present analysis provides an alternative model for DeK1 structure that can help pan both in vitro and in vivo studies. The transmembrane helices were shown to have a number of conserved charged and polar residues that can form salt bridges and help in ligand binding or transmitting an external signal in addition to maintaining structural integrity. The protein possesses a big loop of about 280-300 amino acid residues on the cytoplasmic side of the membrane. It has a number of putative phosphorylation sites, multiple cysteine residues and a high density of charged residues, all of which could be important for protein-protein interaction and signaling pathways. The loop has a nuclear localization propensity as well. The long C-terminal tail of DeK1 with homology to calpain domain may be activated by the big

  2. Global meta-analysis of leaf area index in wetlands indicates uncertainties in understanding of their ecosystem function

    Science.gov (United States)

    Dronova, I.; Taddeo, S.; Foster, K.

    2017-12-01

    Projecting ecosystem responses to global change relies on the accurate understanding of properties governing their functions in different environments. An important variable in models of ecosystem function is canopy leaf area index (LAI; leaf area per unit ground area) declared as one of the Essential Climate Variables in the Global Climate Observing System and extensively measured in terrestrial landscapes. However, wetlands have been largely under-represented in these efforts, which globally limits understanding of their contribution to carbon sequestration, climate regulation and resilience to natural and anthropogenic disturbances. This study provides a global synthesis of >350 wetland-specific LAI observations from 182 studies and compares LAI among wetland ecosystem and vegetation types, biomes and measurement approaches. Results indicate that most wetland types and even individual locations show a substantial local dispersion of LAI values (average coefficient of variation 65%) due to heterogeneity of environmental properties and vegetation composition. Such variation indicates that mean LAI values may not sufficiently represent complex wetland environments, and the use of this index in ecosystem function models needs to incorporate within-site variation in canopy properties. Mean LAI did not significantly differ between direct and indirect measurement methods on a pooled global sample; however, within some of the specific biomes and wetland types significant contrasts between these approaches were detected. These contrasts highlight unique aspects of wetland vegetation physiology and canopy structure affecting measurement principles that need to be considered in generalizing canopy properties in ecosystem models. Finally, efforts to assess wetland LAI using remote sensing strongly indicate the promise of this technology for cost-effective regional-scale modeling of canopy properties similar to terrestrial systems. However, such efforts urgently require more

  3. Understanding soil erosion process within herbaceous vegetative hedges using plant functional traits approach in North-West Europe

    Science.gov (United States)

    Kervroëdan, Léa; Armand, Romain; Saunier, Mathieu; Faucon, Michel-Pierre

    2017-04-01

    Runoff and soil erosion induce major environmental and economic damages. Concentrated runoff control by aboveground plant biomass in upstream areas constitutes a key feature to reduce runoff and soil erosion in Western Europe (WE). Indeed, aboveground plant biomass can reduce runoff and soil erosion respectively by increasing hydraulic roughness and trapping sediments. However, studies of plant effect on runoff reduction are usually based on the taxonomical characterisation of species and do not refer to effect of aboveground plant functional traits. Plant functional traits approach allows to understand ecosystem processes and quantify services. Traits effect could vary depending on hydrological processes (i.e., discharge) and their aggregation could have a synergetic effect on hydraulic roughness and erosion reduction. In this study, objectives are to i) examine effects of aboveground plant functional traits of herbaceous hedges on hydraulic roughness; ii) test the effects of their aggregation on hydraulic roughness. Seven aboveground functional traits were measured on 14 indigenous plant species from North-West Europe with a high morphological variability (stem and leaf densities; stem diameter, stiffness and dry matter content; leaf area and specific leaf area (SLA)). Those species are perennial herbaceous caespitose or comprising dry biomass in winter. Effects of plant functional traits and their abundance within the community on hydraulic roughness were examined using a runoff simulator at four discharges. Furthermore, the effect of plant functional diversity was analysed using four monospecific (mono-trait) conditions compared to multispecific (multi-traits) conditions. Results showed traits and their abundance influence hydraulic roughness. Indeed, leaf density and leaf area (traits), as well as plant community weighted stem, leaf and shoot areas, stem diameter and SLA are significantly correlated to hydraulic roughness. Moreover, leaf density and leaf area

  4. Association of Adiposity and Mental Health Functioning across the Lifespan: Findings from Understanding Society (The UK Household Longitudinal Study)

    Science.gov (United States)

    2016-01-01

    Background Evidence on the adiposity-mental health associations is mixed, with studies finding positive, negative or no associations, and less is known about how these associations may vary by age. Objective To examine the association of adiposity -body mass index (BMI), waist circumference (WC) and percentage body fat (BF%)- with mental health functioning across the adult lifespan. Methods Data from 11,257 participants (aged 18+) of Understanding Society: the UK Household Longitudinal Study (waves 2 and 3, 5/2010-7/2013) were employed. Regressions of mental health functioning, assessed by the Mental Component Summary (MCS-12) and the General Health Questionnaire (GHQ-12), on adiposity measures (continuous or dichotomous indicators) were estimated adjusted for covariates. Polynomial age-adiposity interactions were estimated. Results Higher adiposity was associated with poorer mental health functioning. This emerged in the 30s, increased up to mid-40s (all central adiposity and obesity-BF% measures) or early 50s (all BMI measures) and then decreased with age. Underlying physical health generally accounted for these associations except for central adiposity, where associations remained statistically significant from the mid-30s to50s. Cardiovascular, followed by arthritis and endocrine, conditions played the greatest role in attenuating the associations under investigation. Conclusions We found strong age-specific patterns in the adiposity-mental health functioning association that varied across adiposity measures. Underlying physical health had the dominant role in attenuating these associations. Policy makers and health professionals should target increased adiposity, mainly central adiposity, as it is a risk factor for poor mental health functioning in those aged between mid-30s to 50 years. PMID:26849046

  5. Association of Adiposity and Mental Health Functioning across the Lifespan: Findings from Understanding Society (The UK Household Longitudinal Study.

    Directory of Open Access Journals (Sweden)

    Apostolos Davillas

    Full Text Available Evidence on the adiposity-mental health associations is mixed, with studies finding positive, negative or no associations, and less is known about how these associations may vary by age.To examine the association of adiposity -body mass index (BMI, waist circumference (WC and percentage body fat (BF%- with mental health functioning across the adult lifespan.Data from 11,257 participants (aged 18+ of Understanding Society: the UK Household Longitudinal Study (waves 2 and 3, 5/2010-7/2013 were employed. Regressions of mental health functioning, assessed by the Mental Component Summary (MCS-12 and the General Health Questionnaire (GHQ-12, on adiposity measures (continuous or dichotomous indicators were estimated adjusted for covariates. Polynomial age-adiposity interactions were estimated.Higher adiposity was associated with poorer mental health functioning. This emerged in the 30s, increased up to mid-40s (all central adiposity and obesity-BF% measures or early 50s (all BMI measures and then decreased with age. Underlying physical health generally accounted for these associations except for central adiposity, where associations remained statistically significant from the mid-30s to 50s. Cardiovascular, followed by arthritis and endocrine, conditions played the greatest role in attenuating the associations under investigation.We found strong age-specific patterns in the adiposity-mental health functioning association that varied across adiposity measures. Underlying physical health had the dominant role in attenuating these associations. Policy makers and health professionals should target increased adiposity, mainly central adiposity, as it is a risk factor for poor mental health functioning in those aged between mid-30s to 50 years.

  6. A data-model integration approach toward improved understanding on wetland functions and hydrological benefits at the catchment scale

    Science.gov (United States)

    Yeo, I. Y.; Lang, M.; Lee, S.; Huang, C.; Jin, H.; McCarty, G.; Sadeghi, A.

    2017-12-01

    The wetland ecosystem plays crucial roles in improving hydrological function and ecological integrity for the downstream water and the surrounding landscape. However, changing behaviours and functioning of wetland ecosystems are poorly understood and extremely difficult to characterize. Improved understanding on hydrological behaviours of wetlands, considering their interaction with surrounding landscapes and impacts on downstream waters, is an essential first step toward closing the knowledge gap. We present an integrated wetland-catchment modelling study that capitalizes on recently developed inundation maps and other geospatial data. The aim of the data-model integration is to improve spatial prediction of wetland inundation and evaluate cumulative hydrological benefits at the catchment scale. In this paper, we highlight problems arising from data preparation, parameterization, and process representation in simulating wetlands within a distributed catchment model, and report the recent progress on mapping of wetland dynamics (i.e., inundation) using multiple remotely sensed data. We demonstrate the value of spatially explicit inundation information to develop site-specific wetland parameters and to evaluate model prediction at multi-spatial and temporal scales. This spatial data-model integrated framework is tested using Soil and Water Assessment Tool (SWAT) with improved wetland extension, and applied for an agricultural watershed in the Mid-Atlantic Coastal Plain, USA. This study illustrates necessity of spatially distributed information and a data integrated modelling approach to predict inundation of wetlands and hydrologic function at the local landscape scale, where monitoring and conservation decision making take place.

  7. Simulation modeling to understand how selective foraging by beaver can drive the structure and function of a willow community

    Science.gov (United States)

    Peinetti, H.R.; Baker, B.W.; Coughenour, M.B.

    2009-01-01

    Beaver-willow (Castor-Salix) communities are a unique and vital component of healthy wetlands throughout the Holarctic region. Beaver selectively forage willow to provide fresh food, stored winter food, and construction material. The effects of this complex foraging behavior on the structure and function of willow communities is poorly understood. Simulation modeling may help ecologists understand these complex interactions. In this study, a modified version of the SAVANNA ecosystem model was developed to better understand how beaver foraging affects the structure and function of a willow community in a simulated riparian ecosystem in Rocky Mountain National Park, Colorado (RMNP). The model represents willow in terms of plant and stem dynamics and beaver foraging in terms of the quantity and quality of stems cut to meet the energetic and life history requirements of beaver. Given a site where all stems were equally available, the model suggested a simulated beaver family of 2 adults, 2 yearlings, and 2 kits required a minimum of 4 ha of willow (containing about10 stems m-2) to persist in a steady-state condition. Beaver created a willow community where the annual net primary productivity (ANPP) was 2 times higher and plant architecture was more diverse than the willow community without beaver. Beaver foraging created a plant architecture dominated by medium size willow plants, which likely explains how beaver can increase ANPP. Long-term simulations suggested that woody biomass stabilized at similar values even though availability differed greatly at initial condition. Simulations also suggested that willow ANPP increased across a range of beaver densities until beaver became food limited. Thus, selective foraging by beaver increased productivity, decreased biomass, and increased structural heterogeneity in a simulated willow community.

  8. Understanding Multifunctional Agricultural Land by Using Low Cost and Open Source Solutions to Quantify Ecosystem Function and Services

    Science.gov (United States)

    Forsmoo, Joel; Anderson, Karen; Brazier, Richard; Macleod, Kit; Wilkinson, Mark

    2016-04-01

    There is a need to advance our understanding of how the spatial structure of farmed landscapes contributes to the provision of functions and services. Agricultural land is of critical importance in NW Europe, covering large parts of NW Europe's temperate land. Moreover, these agricultural areas are primarily intensively managed, with a focus on maximizing food and fibre production. Such landscapes therefore can provide a wealth of ecosystem goods and services (ESs) including regulation of climate, erosion regulation, hydrology, water quality, nutrient cycling and biodiversity conservation. However, it has been shown they are key sources of sediment, phosphorous, nitrogen and storm runoff contributing to flooding, and therefore it is likely that most agricultural landscapes do not maximize the services or benefits that they might provide. The focus of this study is the spatio-temporal assessment of carbon sequestration (particularly through proxies such as above-ground biomass) and hydrological processes on agricultural land. Understanding and quantifying both of these is important to (a) inform payments for ecosystem services frameworks, (b) evaluate and improve carbon sequestration models, (c) manage the flood risk, (d) downstream water security and (e) water quality. Quantifying both of these ESs is dependent on data describing the fine spatial and temporal structure and function of the landscape. Common practice has been to use remote sensing techniques, e.g. satellites, providing coarse spatial resolution (around 30cm at 20° off nadir) and/or temporal resolution (around 5 days revisit time at solutions have on the accuracy of the final product, the digital surface model (DSM), by using recently acquired data. Specifically, when applied in a structurally complex field site with irregular surface roughness patterns, over a land use gradient, from livestock grazing to agricultural crops. We will demonstrate the added value of using very fine detail data

  9. Ecosystem function in complex mountain terrain: Combining models and long-term observations to advance process-based understanding

    Science.gov (United States)

    Wieder, William R.; Knowles, John F.; Blanken, Peter D.; Swenson, Sean C.; Suding, Katharine N.

    2017-04-01

    Abiotic factors structure plant community composition and ecosystem function across many different spatial scales. Often, such variation is considered at regional or global scales, but here we ask whether ecosystem-scale simulations can be used to better understand landscape-level variation that might be particularly important in complex terrain, such as high-elevation mountains. We performed ecosystem-scale simulations by using the Community Land Model (CLM) version 4.5 to better understand how the increased length of growing seasons may impact carbon, water, and energy fluxes in an alpine tundra landscape. The model was forced with meteorological data and validated with observations from the Niwot Ridge Long Term Ecological Research Program site. Our results demonstrate that CLM is capable of reproducing the observed carbon, water, and energy fluxes for discrete vegetation patches across this heterogeneous ecosystem. We subsequently accelerated snowmelt and increased spring and summer air temperatures in order to simulate potential effects of climate change in this region. We found that vegetation communities that were characterized by different snow accumulation dynamics showed divergent biogeochemical responses to a longer growing season. Contrary to expectations, wet meadow ecosystems showed the strongest decreases in plant productivity under extended summer scenarios because of disruptions in hydrologic connectivity. These findings illustrate how Earth system models such as CLM can be used to generate testable hypotheses about the shifting nature of energy, water, and nutrient limitations across space and through time in heterogeneous landscapes; these hypotheses may ultimately guide further experimental work and model development.

  10. Hydrologic Synthesis Across the Critical Zone Observatory Network: A Step Towards Understanding the Coevolution of Critical Zone Function and Structure

    Science.gov (United States)

    Wlostowski, A. N.; Harman, C. J.; Molotch, N. P.

    2017-12-01

    generation). Storage-discharge relationships vary widely across the Network, and may be associated with inter-site differences in sub-surface architecture. Moving forward, we seek to reconcile top-down analysis results against the bottom-up understanding of critical zone structure and hydrologic function at each CZO site.

  11. Understanding the notion of function and articulation of semiotic records that represent between students entering a program Engineering

    Directory of Open Access Journals (Sweden)

    Raúl Prada-Núñez

    2016-08-01

    Full Text Available This study aims to assess the understanding of the notion of function and the ability to articulate different semiotic registers for representation by new students in the university in Colombia. Immediate context is taken as the Faculty of Engineering at a public university. Epistemologically the study is based on symbolic interaction by analyzing the meanings that students attributed to this mathematical concept when addressing problem solving. The methodology, therefore, is qualitatively and use of theoretical coding is done. For analysis of the results it has been applied grounded theory with a structured approach. The information generated by this study corresponds to a test that showed students two graphic representations with the intent to identify which of them was a function, besides which should argue their response. Altogether 86 arguments around the concept are analyzed. Data analysis was done through atlas.ti 7.0 software. The system allows a glimpse of emerging categories the following findings: conceptual deficiencies, diversity in conceptual approaches, conceptual referents, semiotic representations, and finally highlight the various conceptual variations.

  12. Using extremely halophilic bacteria to understand the role of surface charge and surface hydration in protein evolution, folding, and function

    Science.gov (United States)

    Hoff, Wouter; Deole, Ratnakar; Osu Collaboration

    2013-03-01

    Halophilic Archaea accumulate molar concentrations of KCl in their cytoplasm as an osmoprotectant, and have evolved highly acidic proteomes that only function at high salinity. We examine osmoprotection in the photosynthetic Proteobacteria Halorhodospira halophila. We find that H. halophila has an acidic proteome and accumulates molar concentrations of KCl when grown in high salt media. Upon growth of H. halophila in low salt media, its cytoplasmic K + content matches that of Escherichia coli, revealing an acidic proteome that can function in the absence of high cytoplasmic salt concentrations. These findings necessitate a reassessment of two central aspects of theories for understanding extreme halophiles. We conclude that proteome acidity is not driven by stabilizing interactions between K + ions and acidic side chains, but by the need for maintaining sufficient solvation and hydration of the protein surface at high salinity through strongly hydrated carboxylates. We propose that obligate protein halophilicity is a non-adaptive property resulting from genetic drift in which constructive neutral evolution progressively incorporates weakly stabilizing K + binding sites on an increasingly acidic protein surface.

  13. Understanding sex differences in form and function of bird song: The importance of studying song learning processes

    Directory of Open Access Journals (Sweden)

    Katharina eRiebel

    2016-06-01

    Full Text Available Birdsong is a culturally transmitted mating signal. Due to historical and geographical biases, song (learning has been predominantly studied in the temperate zones, where female song is rare. Consequently, mechanisms and function of song learning have been almost exclusively studied in male birds and under the premise that inter- and intrasexual selection favoured larger repertoires and complex songs in males. However, female song is not rare outside the temperate zones and song in both sexes probably is the ancestral state in songbirds. Some song dimorphisms seen today might therefore be manifestations of secondary losses of female song. What selection pressures have favoured such losses and other sexual dimorphisms in song? Combined mapping of phylogenetic and ecological correlates of sex differences in song structure and function might provide important clues to the evolution of male and female song. This requires parameterization of the degree of sexual dimorphism. Simple comparison of male-female song might not provide enough resolution, because the same magnitude of difference (e.g. repertoire overlap could result from different processes: the sexes could differ in how well they learn (‘copying fidelity’ or from whom they learn (‘model selection’. Different learning mechanisms might provide important pointers towards different selection pressures. Investigating sex-specific learning could therefore help to identify the social and ecological selection pressures contributing to sex differences in adult song. The study of female song learning in particular could be crucial to our understanding of i song function in males and females and ii the evolution of sex-specific song.

  14. Understanding the relationship between brain and upper limb function in children with unilateral motor impairments: A multimodal approach.

    Science.gov (United States)

    Weinstein, Maya; Green, Dido; Rudisch, Julian; Zielinski, Ingar M; Benthem-Muñiz, Marta; Jongsma, Marijtje L A; McClelland, Verity; Steenbergen, Bert; Shiran, Shelly; Ben Bashat, Dafna; Barker, Gareth J

    2018-01-01

    ) and a mixed (n = 1) connectivity pattern; again without clear association with MMs. No differences were found between children with and without MMs in lesion scores, motor fMRI laterality indices, CST diffusivity values, and upper limb function. In the genu, midbody, and splenium of the CC, higher fractional anisotropy values were found in children with MMs compared to children without MMs. The EEG data indicated a stronger mu-restoration above the contralateral hemisphere in 6/8 children and above the ipsilateral hemisphere in 2/8 children. The current results demonstrate benefits from the use of different modalities when studying upper-limb function in children with CP; not least to accommodate to the variations in tolerance and feasibility of implementation of the differing methods. These exposed multiple individual brain-reorganization patterns corresponding to different functional motor abilities. Additional research is warranted to understand the transactional influences of early brain injury, neuroplasticity and developmental and environmental factors on hand function in order to develop targeted interventions. Copyright © 2017 European Paediatric Neurology Society. Published by Elsevier Ltd. All rights reserved.

  15. Computational modeling of a forward lunge: towards a better understanding of the function of the cruciate ligaments

    Science.gov (United States)

    Alkjær, Tine; Wieland, Maja R; Andersen, Michael S; Simonsen, Erik B; Rasmussen, John

    2012-01-01

    This study investigated the function of the cruciate ligaments during a forward lunge movement. The mechanical roles of the anterior and posterior cruciate ligament (ACL, PCL) during sagittal plane movements, such as forward lunging, are unclear. A forward lunge movement contains a knee joint flexion and extension that is controlled by the quadriceps muscle. The contraction of the quadriceps can cause anterior tibial translation, which may strain the ACL at knee joint positions close to full extension. However, recent findings suggest that it is the PCL rather than the ACL which is strained during forward lunging. Thus, the purpose of the present study was to establish a musculoskeletal model of the forward lunge to computationally investigate the complete mechanical force equilibrium of the tibia during the movement to examine the loading pattern of the cruciate ligaments. A healthy female was selected from a group of healthy subjects who all performed a forward lunge on a force platform, targeting a knee flexion angle of 90°. Skin-markers were placed on anatomical landmarks on the subject and the movement was recorded by five video cameras. The three-dimensional kinematic data describing the forward lunge movement were extracted and used to develop a biomechanical model of the lunge movement. The model comprised two legs including femur, crus, rigid foot segments and the pelvis. Each leg had 35 independent muscle units, which were recruited according to a minimum fatigue criterion. This approach allowed a full understanding of the mechanical equilibrium of the knee joint, which revealed that the PCL had an important stabilizing role in the forward lunge movement. In contrast, the ACL did not have any significant mechanical function during the lunge movement. Furthermore, the results showed that m. gluteus maximus may play a role as a knee stabilizer in addition to the hamstring muscles. PMID:23057673

  16. The Ever-Evolving Concept of the Gene: The Use of RNA/Protein Experimental Techniques to Understand Genome Functions

    Directory of Open Access Journals (Sweden)

    Andrea Cipriano

    2018-03-01

    Full Text Available The completion of the human genome sequence together with advances in sequencing technologies have shifted the paradigm of the genome, as composed of discrete and hereditable coding entities, and have shown the abundance of functional noncoding DNA. This part of the genome, previously dismissed as “junk” DNA, increases proportionally with organismal complexity and contributes to gene regulation beyond the boundaries of known protein-coding genes. Different classes of functionally relevant nonprotein-coding RNAs are transcribed from noncoding DNA sequences. Among them are the long noncoding RNAs (lncRNAs, which are thought to participate in the basal regulation of protein-coding genes at both transcriptional and post-transcriptional levels. Although knowledge of this field is still limited, the ability of lncRNAs to localize in different cellular compartments, to fold into specific secondary structures and to interact with different molecules (RNA or proteins endows them with multiple regulatory mechanisms. It is becoming evident that lncRNAs may play a crucial role in most biological processes such as the control of development, differentiation and cell growth. This review places the evolution of the concept of the gene in its historical context, from Darwin's hypothetical mechanism of heredity to the post-genomic era. We discuss how the original idea of protein-coding genes as unique determinants of phenotypic traits has been reconsidered in light of the existence of noncoding RNAs. We summarize the technological developments which have been made in the genome-wide identification and study of lncRNAs and emphasize the methodologies that have aided our understanding of the complexity of lncRNA-protein interactions in recent years.

  17. Of mice and men: how animal models advance our understanding of T-cell function in RA.

    Science.gov (United States)

    Kobezda, Tamás; Ghassemi-Nejad, Sheida; Mikecz, Katalin; Glant, Tibor T; Szekanecz, Zoltán

    2014-03-01

    The involvement of autoreactive T cells in the pathogenesis of rheumatoid arthritis (RA) as well as in autoimmune animal models of arthritis has been well established; however, unanswered questions, such as the role of joint-homing T cells, remain. Animal models of arthritis are superb experimental tools in demonstrating how T cells trigger joint inflammation, and thus can help to further our knowledge of disease mechanisms and potential therapies. In this Review, we discuss the similarities and differences in T-cell subsets and functions between RA and mouse arthritis models. For example, various T-cell subsets are involved in both human and mouse arthritis, but differences might exist in the cytokine regulation and plasticity of these cells. With regard to joint-homing T cells, an abundance of synovial T cells is present in humans compared with mice. On the other hand, local expansion of type 17 T-helper (TH17) cells is observed in some animal models, but not in RA. Finally, whereas T-cell depletion therapy essentially failed in RA, antibody targeting of T cells can work, at least preventatively, in most arthritis models. Clearly, additional human and animal studies are needed to fill the gap in our understanding of the specific contribution of T-cell subsets to arthritis in mice and men.

  18. Arabidopsis mutants in sphingolipid synthesis as tools to understand the structure and function of membrane microdomains in plasmodesmata

    Directory of Open Access Journals (Sweden)

    ARIADNA eGONZÁLEZ-SOLÍS

    2014-01-01

    Full Text Available Plasmodesmata –intercellular channels that communicate adjacent cells– possess complex membranous structures. Recent evidences indicate that plasmodesmata contain membrane microdomains. In order to understand how these submembrane regions collaborate to plasmodesmata function, it is necessary to characterize their size, composition and dynamics. An approach that can shed light on these microdomain features is based on the use of Arabidopsis mutants in sphingolipid synthesis. Sphingolipids are canonical components of microdomains together with sterols and some glycerolipids. Moreover, sphingolipids are transducers in pathways that display programmed cell death as a defense mechanism against pathogens. The study of Arabidopsis mutants would allow determining which structural features of the sphingolipids are important for the formation and stability of microdomains, and if defense signaling networks using sphingoid bases as second messengers are associated to plasmodesmata operation. Such studies need to be complemented by analysis of the ultrastructure and the use of protein probes for plasmodesmata microdomains and may constitute a very valuable source of information to analyze these membrane structures.

  19. Arabidopsis mutants in sphingolipid synthesis as tools to understand the structure and function of membrane microdomains in plasmodesmata

    Science.gov (United States)

    González-Solís, Ariadna; Cano-Ramírez, Dora L.; Morales-Cedillo, Francisco; Tapia de Aquino, Cinthya; Gavilanes-Ruiz, Marina

    2013-01-01

    Plasmodesmata—intercellular channels that communicate adjacent cells—possess complex membranous structures. Recent evidences indicate that plasmodesmata contain membrane microdomains. In order to understand how these submembrane regions collaborate to plasmodesmata function, it is necessary to characterize their size, composition and dynamics. An approach that can shed light on these microdomain features is based on the use of Arabidopsis mutants in sphingolipid synthesis. Sphingolipids are canonical components of microdomains together with sterols and some glycerolipids. Moreover, sphingolipids are transducers in pathways that display programmed cell death as a defense mechanism against pathogens. The study of Arabidopsis mutants would allow determining which structural features of the sphingolipids are important for the formation and stability of microdomains, and if defense signaling networks using sphingoid bases as second messengers are associated to plasmodesmata operation. Such studies need to be complemented by analysis of the ultrastructure and the use of protein probes for plasmodesmata microdomains and may constitute a very valuable source of information to analyze these membrane structures. PMID:24478783

  20. Understanding the Function of Genes Involved in Inherited Retinal Degeneration-Insights into the Pathogenesis and Function of C8ORF37

    Science.gov (United States)

    Sharif, Ali Sakawa

    -downs identified KTN1, RAB28, UCHL1, and PSMD14 suggesting that C8ORF37 may have a role in protein homeostasis. Chapter 4 concludes and discusses the impact of generating and characterizing C8orf37 animal models for future studies in understanding photoreceptor function and in the development of therapeutics against retinal degeneration.

  1. Regional Differential Effects of the Novel Histamine H3 Receptor Antagonist 6-[(3-Cyclobutyl-2,3,4,5-tetrahydro-1H-3-benzazepin-7-yl)oxy]-N-methyl-3-pyridinecarboxamide hydrochloride (GSK189254) on Histamine Release in the Central Nervous System of Freely Moving Rats

    OpenAIRE

    Giannoni, Patrizia; Medhurst, Andrew D.; Passani, Maria Beatrice; Giovannini, Maria Grazia; Ballini, Chiara; Corte, Laura Della; Blandina, Patrizio

    2010-01-01

    After oral administration, the nonimidazole histamine H3 receptor antagonist, 6-[(3-cyclobutyl-2,3,4,5-tetrahydro-1H-3-benzazepin-7-yl)oxy]-N-methyl-3-pyridinecarboxamide hydrochloride (GSK189254), increased histamine release from the tuberomammillary nucleus, where all histaminergic somata are localized, and from where their axons project to the entire brain. To further understand functional histaminergic circuitry in the brain, dual-probe microdialysis was used to pharmacologically block H3...

  2. Teaching Teaching & Understanding Understanding

    DEFF Research Database (Denmark)

    2006-01-01

    "Teaching Teaching & Understanding Understanding" is a 19-minute award-winning short-film about teaching at university and higher-level educational institutions. It is based on the "Constructive Alignment" theory developed by Prof. John Biggs. The film delivers a foundation for understanding what...

  3. Using Solution Strategies to Examine and Promote High-School Students' Understanding of Exponential Functions: One Teacher's Attempt

    Science.gov (United States)

    Brendefur, Jonathan

    2014-01-01

    Much research has been conducted on how elementary students develop mathematical understanding and subsequently how teachers might use this information. This article builds on this type of work by investigating how one high-school algebra teacher designs and conducts a lesson on exponential functions. Through a lesson study format she studies with…

  4. Advances in the understanding of early Huntington's disease using the functional imaging techniques of PET and SPET

    International Nuclear Information System (INIS)

    Andrews, T.C.; Brooks, D.J.

    1998-01-01

    The functional imaging techniques of positron emission tomography (PET) and single photon emission tomography (SPET) have been used to study regional brain function in Huntington's disease (HD) in vivo. Reduced striatal glucose metabolism and dopamine receptor binding are evident in all symptomatic HD patients and in ∼50% of asymptomatic adult mutation carriers. These characteristics correlate with clinical measures of disease severity. Reduced cortical glucose metabolism and dopamine receptor binding, together with reduced striatal and cortical opioid receptor binding, have also been demonstrated in symptomatic patients with HD. Repeat PET measures of striatal function have been used to monitor the progression of this disease objectively. In the future, functional imaging will provide a valuable way of assessing the efficacy of both fetal striatal cell implants and putative neuroprotective agents, such as nerve growth factors. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  5. Significance of functional disease-causal/susceptible variants identified by whole-genome analyses for the understanding of human diseases.

    Science.gov (United States)

    Hitomi, Yuki; Tokunaga, Katsushi

    2017-01-01

    Human genome variation may cause differences in traits and disease risks. Disease-causal/susceptible genes and variants for both common and rare diseases can be detected by comprehensive whole-genome analyses, such as whole-genome sequencing (WGS), using next-generation sequencing (NGS) technology and genome-wide association studies (GWAS). Here, in addition to the application of an NGS as a whole-genome analysis method, we summarize approaches for the identification of functional disease-causal/susceptible variants from abundant genetic variants in the human genome and methods for evaluating their functional effects in human diseases, using an NGS and in silico and in vitro functional analyses. We also discuss the clinical applications of the functional disease causal/susceptible variants to personalized medicine.

  6. The role of coherence of mind and reflective functioning in understanding binge-eating disorder and co-morbid overweight.

    Science.gov (United States)

    Maxwell, Hilary; Tasca, Giorgio A; Grenon, Renee; Faye, Megan; Ritchie, Kerri; Bissada, Hany; Balfour, Louise

    2017-08-01

    Coherence of mind and reflective functioning may impact negative affect and interpersonal functioning over and above the effects of symptoms of depression and interpersonal problems that contribute to symptoms of binge-eating disorder (BED) and overweight/obesity. Matched samples of overweight women with BED and overweight and normal weight women without BED completed the Adult Attachment Interview, a measure of depressive symptoms, and a measure of interpersonal problems. Greater symptoms of depression distinguished women with BED from the matched comparison samples. Greater interpersonal problems differentiated women with BED from overweight women without BED. Coherence of Mind scores did not differentiate the samples. However, lower Reflective Functioning scores did distinguish both women with BED and overweight women without BED from normal weight women. Lower reflective functioning may lead to binge eating independent of depressive symptoms and interpersonal problems.

  7. Understanding the function and dysfunction of the immune system in lung cancer: the role of immune checkpoints

    International Nuclear Information System (INIS)

    Karachaliou, Niki; Cao, Maria Gonzalez; Teixidó, Cristina; Viteri, Santiago; Morales-Espinosa, Daniela; Santarpia, Mariacarmela; Rosell, Rafael

    2015-01-01

    Survival rates for metastatic lung cancer, including non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC), are poor with 5-year survivals of less than 5%. The immune system has an intricate and complex relationship with tumorigenesis; a groundswell of research on the immune system is leading to greater understanding of how cancer progresses and presenting new ways to halt disease progress. Due to the extraordinary power of the immune system—with its capacity for memory, exquisite specificity and central and universal role in human biology—immunotherapy has the potential to achieve complete, long-lasting remissions and cures, with few side effects for any cancer patient, regardless of cancer type. As a result, a range of cancer therapies are under development that work by turning our own immune cells against tumors. However deeper understanding of the complexity of immunomodulation by tumors is key to the development of effective immunotherapies, especially in lung cancer

  8. Understanding the function and dysfunction of the immune system in lung cancer: the role of immune checkpoints.

    Science.gov (United States)

    Karachaliou, Niki; Cao, Maria Gonzalez; Teixidó, Cristina; Viteri, Santiago; Morales-Espinosa, Daniela; Santarpia, Mariacarmela; Rosell, Rafael

    2015-06-01

    Survival rates for metastatic lung cancer, including non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC), are poor with 5-year survivals of less than 5%. The immune system has an intricate and complex relationship with tumorigenesis; a groundswell of research on the immune system is leading to greater understanding of how cancer progresses and presenting new ways to halt disease progress. Due to the extraordinary power of the immune system-with its capacity for memory, exquisite specificity and central and universal role in human biology-immunotherapy has the potential to achieve complete, long-lasting remissions and cures, with few side effects for any cancer patient, regardless of cancer type. As a result, a range of cancer therapies are under development that work by turning our own immune cells against tumors. However deeper understanding of the complexity of immunomodulation by tumors is key to the development of effective immunotherapies, especially in lung cancer.

  9. Functional traits of trees on and off termite mounds: Understanding the origin of biotically-driven heterogeneity in savannas

    OpenAIRE

    van der Plas, F.; Howison, R.; Reinders, J.; Fokkema, W.; Olff, H.

    2013-01-01

    Questions In African savannas, Macrotermes termites contribute to small-scale heterogeneity by constructing large mounds. Operating as islands of high nutrient and water availability and low fire frequency, these mounds support distinct, diverse communities of trees that have been shown to be highly attractive to browsers. However, the distinct traits of tree species on termite mounds have hardly been studied, even though this may help to understand processes determining (1) their characteris...

  10. Does spasticity interfere with functional recovery after stroke? A novel approach to understand, measure and treat spasticity after acute stroke

    NARCIS (Netherlands)

    Malhotra, S.; Malhotra, Shweta

    2013-01-01

    The principal aim of this thesis is on identifying if spasticity on the wrist after an acute stroke interferes with functional recovery of the upper limb.This randomized study demonstrated that sNMES treatment along with standardized upper limb therapy improves muscle strength for wrist extension

  11. Specifying Links between Executive Functioning and Theory of Mind during Middle Childhood: Cognitive Flexibility Predicts Social Understanding

    Science.gov (United States)

    Bock, Allison M.; Gallaway, Kristin C.; Hund, Alycia M.

    2015-01-01

    The purpose of this study was to specify the development of and links between executive functioning and theory of mind during middle childhood. One hundred four 7- to 12-year-old children completed a battery of age-appropriate tasks measuring working memory, inhibition, flexibility, theory of mind, and vocabulary. As expected, spatial working…

  12. Incorporating Modeling and Simulations in Undergraduate Biophysical Chemistry Course to Promote Understanding of Structure-Dynamics-Function Relationships in Proteins

    Science.gov (United States)

    Hati, Sanchita; Bhattacharyya, Sudeep

    2016-01-01

    A project-based biophysical chemistry laboratory course, which is offered to the biochemistry and molecular biology majors in their senior year, is described. In this course, the classroom study of the structure-function of biomolecules is integrated with the discovery-guided laboratory study of these molecules using computer modeling and…

  13. Understanding the effects of packing and chemical terminations on the optical excitations of azobenzene-functionalized self-assembled monolayers

    Science.gov (United States)

    Cocchi, Caterina; Draxl, Claudia

    2017-10-01

    In a first-principles study based on many-body perturbation theory, we analyze the optical excitations of azobenzene-functionalized self-assembled monolayers (SAMs) with increasing packing density and different terminations, considering for comparison the corresponding gas-phase molecules and dimers. Intermolecular coupling increases with the density of the chromophores independently of the functional groups. The intense π → π* resonance that triggers photo-isomerization is present in the spectra of isolated dimers and diluted SAMs, but it is almost completely washed out in tightly packed architectures. Intermolecular coupling is partially inhibited by mixing differently functionalized azobenzene derivatives, in particular when large groups are involved. In this way, the excitation band inducing the photo-isomerization process is partially preserved and the effects of dense packing partly counterbalanced. Our results suggest that a tailored design of azobenzene-functionalized SAMs which optimizes the interplay between the packing density of the chromophores and their termination can lead to significant improvements in the photo-switching efficiency of these systems.

  14. Using a Multidimensional IRT Framework to Better Understand Differential Item Functioning (DIF): A Tale of Three DIF Detection Procedures

    Science.gov (United States)

    Walker, Cindy M.; Gocer Sahin, Sakine

    2017-01-01

    The theoretical reason for the presence of differential item functioning (DIF) is that data are multidimensional and two groups of examinees differ in their underlying ability distribution for the secondary dimension(s). Therefore, the purpose of this study was to determine how much the secondary ability distributions must differ before DIF is…

  15. On understanding the relationship between structure in the potential surface and observables in classical dynamics: A functional sensitivity analysis approach

    International Nuclear Information System (INIS)

    Judson, R.S.; Rabitz, H.

    1987-01-01

    The relationship between structure in the potential surface and classical mechanical observables is examined by means of functional sensitivity analysis. Functional sensitivities provide maps of the potential surface, highlighting those regions that play the greatest role in determining the behavior of observables. A set of differential equations for the sensitivities of the trajectory components are derived. These are then solved using a Green's function method. It is found that the sensitivities become singular at the trajectory turning points with the singularities going as eta -3 /sup // 2 , with eta being the distance from the nearest turning point. The sensitivities are zero outside of the energetically and dynamically allowed region of phase space. A second set of equations is derived from which the sensitivities of observables can be directly calculated. An adjoint Green's function technique is employed, providing an efficient method for numerically calculating these quantities. Sensitivity maps are presented for a simple collinear atom--diatom inelastic scattering problem and for two Henon--Heiles type Hamiltonians modeling

  16. Understanding and Evaluating L2 Personal Letter Writing: A Systemic Functional Linguistics Analysis of Student Texts in German

    Science.gov (United States)

    Crane, Cori

    2016-01-01

    Adopting a genre lens informed by Systemic Functional Linguistics (cf. Halliday & Matthiessen, [Halliday, M. A. K., 2004]; Martin & Rose, [Martin, J. R., 2008]), this paper explores the text-structural and lexico-grammatical choices that second language (L2) writers of German make in personal letter writing. Close analysis of two student…

  17. Understanding the Function of Tuberous Sclerosis Complex Genes in Neural Development: Roles in Synapse Assembly and Axon Guidance

    Science.gov (United States)

    2012-02-01

    with tuberous sclerosis as well as other epileptic syndromes. Finally, we examined the function of a key downstream element of TOR-TSC...enhances GABA(A) receptor cell-surface expression by a phosphatidylinositol 3-kinase/Akt pathway—Rele- vance to sepsis-associated encephalopathy . J

  18. Improving patients' understanding of terms and phrases commonly used in self-reported measures of sexual function.

    Science.gov (United States)

    Alexander, Angel M; Flynn, Kathryn E; Hahn, Elizabeth A; Jeffery, Diana D; Keefe, Francis J; Reeve, Bryce B; Schultz, Wesley; Reese, Jennifer Barsky; Shelby, Rebecca A; Weinfurt, Kevin P

    2014-08-01

    There is a significant gap in research regarding the readability and comprehension of existing sexual function measures. Patient-reported outcome measures may use terms not well understood by respondents with low literacy. This study aims to test comprehension of words and phrases typically used in sexual function measures to improve validity for all individuals, including those with low literacy. We recruited 20 men and 28 women for cognitive interviews on version 2.0 of the Patient-Reported Outcome Measurement Information System(®) (PROMIS(®) ) Sexual Function and Satisfaction measures. We assessed participants' reading level using the word reading subtest of the Wide Range Achievement Test. Sixteen participants were classified as having low literacy. In the first round of cognitive interviews, each survey item was reviewed by five or more people, at least two of whom had lower than a ninth-grade reading level (low literacy). Patient feedback was incorporated into a revised version of the items. In the second round of interviews, an additional three or more people (at least one with low literacy) reviewed each revised item. Participants with low literacy had difficulty comprehending terms such as aroused, orgasm, erection, ejaculation, incontinence, and vaginal penetration. Women across a range of literacy levels had difficulty with clinical terms like labia and clitoris. We modified unclear terms to include parenthetical descriptors or slang equivalents, which generally improved comprehension. Common words and phrases used across measures of self-reported sexual function are not universally understood. Researchers should appreciate these misunderstandings as a potential source of error in studies using self-reported measures of sexual function. This study also provides evidence for the importance of including individuals with low literacy in cognitive pretesting during the measure development. © 2014 International Society for Sexual Medicine.

  19. A functional genomics approach to understand the control and regulation of storage protein biosynthesis in barley grain

    DEFF Research Database (Denmark)

    Vincze, É; Hansen, M; Bowra, S

    2008-01-01

    The aim of the study was to obtain an insight into amino acid and storage protein metabolism in the developing barley grain at the molecular level. Our strategy was to analyse the transcriptome of relevant pathways in developing grains of field grown barley using a grain specific microarray assem...... pathways in the barley grain. The study described here could provide a strong complement to existing knowledge assisting further  understanding of seed development and thereby provide a foundation for plant breeding towards storage protein with improved nutritional quality....

  20. Steps towards understanding the phonological output buffer and its role in the production of numbers, morphemes, and function words.

    Science.gov (United States)

    Dotan, Dror; Friedmann, Naama

    2015-02-01

    The Stimulus Type Effect on Phonological and Semantic errors (STEPS) describes the phenomenon in which a person, following brain damage, produces words with phonological errors (fine → fige), but number words with semantic errors (five → eight). To track the origins of this phenomenon and find out whether it is limited to numbers, we assessed the speech production of six individuals with conduction aphasia following a damage in the left hemisphere, who made phonological errors in words. STEPS was found in all six participants, and was not limited to number words - several other word categories were also produced with semantic rather than phonological errors: function words, English letter names, and morphological affixes were substituted with other words within their category. This supports the building blocks hypothesis: when phonological sequences serve as building blocks in a productive process, they end up having pre-assembled phonological representations, ready for articulation. STEPS reflects a deficit that causes substitutions of one phonological unit with another. In the case of plain content words, this causes substitutions of one phoneme with another, but in the case of pre-assembled phonological units, this causes substitutions of number words with other number words, function words with function words, and morphological affixes with other affixes. An analysis of the participants' functional locus of deficit revealed that they all had a deficit in the phonological output buffer, and this was their only common deficit. We therefore concluded that the pre-assembled phonological units are stored in dedicated mini-stores in the phonological output buffer, which processes not only phonemes but also whole number words, function words, and morphemes. We also found that STEPS depends on the word's role: number words were produced with semantic errors only when they appeared in numeric context, and function words triggered semantic errors only in

  1. Understanding looping kinetics of a long polymer molecule in solution. Exact solution for delta function sink model

    Science.gov (United States)

    Ganguly, Moumita; Chakraborty, Aniruddha

    2017-10-01

    A diffusion theory for intramolecular reactions of polymer chain in dilute solution is formulated. We give a detailed analytical expression for calculation of rate of polymer looping in solution. The physical problem of looping can be modeled mathematically with the use of a Smoluchowski-like equation with a Dirac delta function sink of finite strength. The solution of this equation is expressed in terms of Laplace Transform of the Green's function for end-to-end motion of the polymer in absence of the sink. We have defined two different rate constants, the long term rate constant and the average rate constant. The average rate constant and long term rate constant varies with several parameters such as length of the polymer (N), bond length (b) and the relaxation time τR. The long term rate constant is independent of the initial probability distribution.

  2. Understanding dissemination and implementation of a new intervention in assisted living settings: the case of function-focused care.

    Science.gov (United States)

    Resnick, Barbara; Galik, Elizabeth; Gruber-Baldini, Ann; Zimmerman, Sheryl

    2013-04-01

    Function-focused care (FFC) was developed to change the philosophy of care in assisted living (AL) to one in which nurses, direct care workers (DCWs) and other members of the health care team work with residents to optimize function and time spent in physical activities. The purpose of this article is to describe dissemination and implementation of FFC within the two assisted living communities in Maryland that were randomized to our FFC for assisted living intervention (FFC-AL). The reach, efficacy/effectiveness, adoption, implementation, and maintenance (RE-AIM) model was used to evaluate dissemination and implementation of FFC in these communities. A total of 171 residents and 96 DCWs consented to participate in the study and outcomes based on data collected from the participants as well as evidence for dissemination and implementation at the site level are provided. Findings can be used to guide others in dissemination and implementation of similar interventions in AL communities.

  3. Understanding the Biological Roles of Pectins in Plants through Physiological and Functional Characterizations of Plant and Fungal Mutants

    DEFF Research Database (Denmark)

    Stranne, Maria

    polysaccharides and consist of backbones rich in galacturonic acids, which are decorated with a range of functional groups including acetyl esters and arabinan sidechains. Although much effort has been made to uncover biological functions of pectins in plants and remarkable progresses have taken place, many...... aspects remain elusive. Studies described in this thesis aimed at gaining new insights into the biological roles of pectin acetylation and arabinosylation in the model plant Arabidopsis thaliana. The thesis consists of four chapters: physiological characterization of cell wall mutants affected in cell......-degrading enzyme secreted by B. cinerea during infection of plants (Chapter 5). The results described resulted in valuable new knowledge regarding the role of pectin acetylation and arabinosylation in the model plant Arabidopsis thaliana documented in three published research papers, one manuscript and one...

  4. Transcriptome of the NTS in exercise-trained spontaneously hypertensive rats: implications for NTS function and plasticity in regulating blood pressure.

    Science.gov (United States)

    Waki, Hidefumi; Gouraud, Sabine S; Bhuiyan, Mohammad E R; Takagishi, Miwa; Yamazaki, Toshiya; Kohsaka, Akira; Maeda, Masanobu

    2013-01-07

    The nucleus tractus solitarii (NTS) controls the cardiovascular system during exercise, and alteration of its function may underlie exercise-induced cardiovascular adaptation. To understand the molecular basis of the NTS's plasticity in regulating blood pressure (BP) and its potential contribution to the antihypertensive effects, we characterized the gene expression profiles at the level of the NTS after long-term daily wheel running in spontaneously hypertensive rats (SHRs). Genome-wide microarray analysis was performed to screen for differentially expressed genes in the NTS between exercise-trained (12 wk) and control SHRs. Pathway analysis using the Kyoto Encyclopedia of Genes and Genomes database revealed that daily exercise altered the expression levels of NTS genes that are functionally associated with metabolic pathways (5 genes), neuroactive ligand-receptor interactions (4 genes), cell adhesion molecules (3 genes), and cytokine-cytokine receptor interactions (3 genes). One of the genes that belonged to the neuroactive ligand-receptor interactions category was histamine receptor H(1). Since we confirmed that the pressor response induced by activation of this receptor is increased after long-term daily exercise, it is suggested that functional plasticity in the histaminergic system may mediate the facilitation of blood pressure control in response to exercise but may not be involved in the lowered basal BP level found in exercise-trained SHRs. Since abnormal inflammatory states in the NTS are known to be prohypertensive in SHRs, altered gene expression of the inflammatory molecules identified in this study may be related to the antihypertensive effects in exercise-trained SHRs, although such speculation awaits functional validation.

  5. Understanding Resilience

    Directory of Open Access Journals (Sweden)

    Gang eWu

    2013-02-01

    Full Text Available Resilience is the ability to adapt successfully in the face of stress and adversity. Stressful life events, trauma and chronic adversity can have a substantial impact on brain function and structure, and can result in the development of PTSD, depression and other psychiatric disorders. However, most individuals do not develop such illnesses after experiencing stressful life events, and are thus thought to be resilient. Resilience as successful adaptation relies on effective responses to environmental challenges and ultimate resistance to the deleterious effects of stress, therefore a greater understanding of the factors that promote such effects is of great relevance. This review focuses on recent findings regarding genetic, epigenetic, developmental, psychosocial and neurochemical factors that are considered essential contributors to the development of resilience. Neural circuits and pathways involved in mediating resilience are also discussed. The growing understanding of resilience factors will hopefully lead to the development of new pharmacological and psychological interventions for enhancing resilience and mitigating the untoward consequences.

  6. Using video technology to disseminate behavioral procedures: a review of Functional Analysis: a Guide for Understanding Challenging Behavior (DVD).

    Science.gov (United States)

    Carr, James E; Fox, Eric J

    2009-01-01

    Although applied behavior analysis has generated many highly effective behavior-change procedures, the procedures have not always been effectively disseminated. One solution to this problem is the use of video technology, which has been facilitated by the ready availability of video production equipment and software and multiple distribution methods (e.g., DVD, online streaming). We review a recent DVD that was produced to disseminate the successful experimental functional analysis procedure. The review is followed by general recommendations for disseminating behavior-analytic procedures via video technology.

  7. Understanding and Calibrating Density-Functional-Theory Calculations Describing the Energy and Spectroscopy of Defect Sites in Hexagonal Boron Nitride.

    Science.gov (United States)

    Reimers, Jeffrey R; Sajid, A; Kobayashi, Rika; Ford, Michael J

    2018-03-13

    Defect states in 2-D materials present many possible uses but both experimental and computational characterization of their spectroscopic properties is difficult. We provide and compare results from 13 DFT and ab initio computational methods for up to 25 excited states of a paradigm system, the V N C B defect in hexagonal boron nitride (h-BN). Studied include: (i) potentially catastrophic effects for computational methods arising from the multireference nature of the closed-shell and open-shell states of the defect, which intrinsically involves broken chemical bonds, (ii) differing results from DFT and time-dependent DFT (TDDFT) calculations, (iii) comparison of cluster models to periodic-slab models of the defect, (iv) the starkly differing effects of nuclear relaxation on the various electronic states that control the widths of photoabsorption and photoemission spectra as broken bonds try to heal, (v) the effect of zero-point energy and entropy on free-energy differences, (vi) defect-localized and conduction/valence-band transition natures, and (vii) strategies needed to ensure that the lowest-energy state of a defect can be computationally identified. Averaged state-energy differences of 0.3 eV are found between CCSD(T) and MRCI energies, with thermal effects on free energies sometimes also being of this order. However, DFT-based methods can perform very poorly. Simple generalized-gradient functionals like PBE fail at the most basic level and should never be applied to defect states. Hybrid functionals like HSE06 work very well for excitations within the triplet manifold of the defect, with an accuracy equivalent to or perhaps exceeding the accuracy of the ab initio methods used. However, HSE06 underestimates triplet-state energies by on average of 0.7 eV compared to closed-shell singlet states, while open-shell singlet states are predicted to be too low in energy by 1.0 eV. This leads to misassignment of the ground state of the V N C B defect. Long

  8. Complex function in the dynamic brain. Comment on “Understanding brain networks and brain organization” by Luiz Pessoa

    Science.gov (United States)

    Anderson, Michael L.

    2014-09-01

    There is much to commend in this excellent overview of the progress we've made toward-and the challenges that remain for-developing an empirical framework for neuroscience that is adequate to the dynamic complexity of the brain [17]. Here I will limit myself first to highlighting the concept of dynamic affiliation, which I take to be the central feature of the functional architecture of the brain, and second to clarifying Pessoa's brief discussion of the ontology of cognition, to be sure readers appreciate this crucial issue.

  9. The use of Functional Resonance Analysis Method (FRAM) in a mid-air collision to understand some characteristics of the air traffic management system resilience

    International Nuclear Information System (INIS)

    Rodrigues de Carvalho, Paulo Victor

    2011-01-01

    The Functional Resonance Analysis Model (FRAM) defines a systemic framework to model complex systems for accident analysis purposes. We use FRAM in the mid-air collision between flight GLO1907, a commercial aircraft Boeing 737-800, and flight N600XL, an executive jet EMBRAER E-145, to investigate key resilience characteristics of the Air Traffic Management System (ATM). This ATM system related accident occurred at 16:56 Brazilian time on September 29, 2006 in the Amazonian sky. FRAM analysis of flight monitoring functions showed system constraints (equipment, training, time, and supervision) that produce variability in system behavior, creating demand resources mismatches in an attempt to perceive and control the developing situation. This variability also included control and coordination breakdowns and automation surprises (TCAS functioning). The analysis showed that under normal variability conditions (without catastrophic failures) the ATM system (pilots, controllers, supervisors, and equipment) was not able to close the control loops of the flight monitoring functions using feedback or feedforward strategies to achieve an adequate control of an aircraft flying in the controlled air space. Our findings shed some light on the resilience of Brazilian ATM system operation and indicated that there is a need of a deeper understanding on how the system is actually functioning. - Highlights: → The Functional Resonance Analysis Model (FRAM) was used in a mid-air collision over Amazon. → The aim was to understand key resilience characteristics of the Air Traffic Management System (ATM). → The analysis showed how, under normal conditions, the system was not able to control flight functions. → The findings shed some light about the resilience of Brazilian ATM system operation.

  10. Understanding the functional anatomy of the frontalis and glabellar complex for optimal aesthetic botulinum toxin type A therapy.

    Science.gov (United States)

    Lorenc, Z Paul; Smith, Stacy; Nestor, Mark; Nelson, Diane; Moradi, Amir

    2013-10-01

    Botulinum neurotoxin type A (BoNTA) is approved for the treatment of glabellar lines and also is commonly injected in an off-label fashion in the frontalis (i.e., frontalis epicranius) muscle to improve the appearance of horizontal forehead lines. This study aimed to review and discuss both the anatomy and physiology of the frontalis muscle and its relationship with antagonist muscles in the upper face and to provide a guide for the use of BoNTA to treat forehead rhytides while minimizing the occurrence of complications such as brow ptosis. A PubMed search was conducted to identify practitioner opinion and clinical publications on the efficacy and safety of BoNTA for aesthetic treatment of the upper face. The use of BoNTA produces durable improvement in the appearance of moderate to severe horizontal forehead lines. Dose and injection technique must be adjusted and individualized based on the variable anatomy and function/mass of muscles in the forehead and upper face as well as on patient goals. Optimal aesthetic outcomes can be achieved by skillfully balancing the opposing effects of the frontalis muscle and its intricate interactions with the procerus, corrugator supercilii, depressor supercilii, and orbicularis oculi muscles. The use of BoNTA to improve the aesthetic appearance of horizontal forehead lines is optimized when clinicians take into account variations in frontalis muscle function and position, anatomy of the brow, and proper injection technique when they devise individualized treatment regimens.

  11. Long-term functionality of rural water services in developing countries: a system dynamics approach to understanding the dynamic interaction of factors.

    Science.gov (United States)

    Walters, Jeffrey P; Javernick-Will, Amy N

    2015-04-21

    Research has shown that sustainability of rural water infrastructure in developing countries is largely affected by the dynamic and systemic interactions of technical, social, financial, institutional, and environmental factors that can lead to premature water system failure. This research employs system dynamics modeling, which uses feedback mechanisms to understand how these factors interact dynamically to influence long-term rural water system functionality. To do this, the research first identified and aggregated key factors from the literature, then asked water sector experts to indicate the polarity and strength between factors through Delphi and cross impact survey questionnaires, and finally used system dynamics modeling to identify and prioritize feedback mechanisms. The resulting model identified 101 feedback mechanisms that were dominated primarily by three- and four-factor mechanisms that contained some combination of the factors: Water System Functionality, Community, Financial, Government, Management, and Technology, implying these factors were the most influential on long-term functionality. These feedback mechanisms were then scored and prioritized, with the most dominant feedback mechanism identified as Water System Functionality-Community-Finance-Management. This study showcases a way for practitioners to better understand the complexities inherent in rural water development using expert opinion and indicates the need for future research in rural water service sustainability that investigates the dynamic interaction of factors in different contexts.

  12. Recent advances in the understanding of how neuropeptide Y and α-melanocyte stimulating hormone function in adipose physiology

    Science.gov (United States)

    Shipp, Steven L.; Cline, Mark A.; Gilbert, Elizabeth R.

    2016-01-01

    ABSTRACT Communication between the brain and the adipose tissue has been the focus of many studies in recent years, with the “brain-fat axis” identified as a system that orchestrates the assimilation and usage of energy to maintain body mass and adequate fat stores. It is now well-known that appetite-regulating peptides that were studied as neurotransmitters in the central nervous system can act both on the hypothalamus to regulate feeding behavior and also on the adipose tissue to modulate the storage of energy. Energy balance is thus partly controlled by factors that can alter both energy intake and storage/expenditure. Two such factors involved in these processes are neuropeptide Y (NPY) and α-melanocyte stimulating hormone (α-MSH). NPY, an orexigenic factor, is associated with promoting adipogenesis in both mammals and chickens, while α-MSH, an anorexigenic factor, stimulates lipolysis in rodents. There is also evidence of interaction between the 2 peptides. This review aims to summarize recent advances in the study of NPY and α-MSH regarding their role in adipose tissue physiology, with an emphasis on the cellular and molecular mechanisms. A greater understanding of the brain-fat axis and regulation of adiposity by bioactive peptides may provide insights on strategies to prevent or treat obesity and also enhance nutrient utilization efficiency in agriculturally-important species. PMID:27994947

  13. Understanding changes in lignin of Panicum virgatum and Eucalyptus globulus as a function of ionic liquid pretreatment.

    Science.gov (United States)

    Varanasi, Patanjali; Singh, Priyanka; Arora, Rohit; Adams, Paul D; Auer, Manfred; Simmons, Blake A; Singh, Seema

    2012-12-01

    Ionic liquids (ILs) have shown great potential for the reduction of lignin in biomass after pretreatment. Although dilute acid and base pretreatments have been shown to result in pretreated biomass with substantially different lignin composition, there is scarce information on the composition of lignin of IL pretreated biomass. In this work, temperature dependent compositional changes in lignin after IL pretreatment were studied to develop a mechanistic understanding of the process. Panicum virgatum and Eucalyptus globulus were pretreated with 1-ethyl-3-methylimidazolium acetate ([C(2)mim][OAc]). Measurement of syringyl and guaiacyl ratio using pyrolysis-GC/MS and Kamlet-Taft properties of [C(2)mim][OAc] at 120 °C and 160 °C strongly suggest two different modes of IL pretreatment. Preferential breakdown of S-lignin in both eucalyptus and switchgrass at high pretreatment temperature (160 °C) and breakdown of G-lignin for eucalyptus and no preferential break down of either S- or G-lignin in switchgrass was observed at lower pretreatment temperatures (120 °C). Copyright © 2012. Published by Elsevier Ltd.

  14. Conotoxins as Tools to Understand the Physiological Function of Voltage-Gated Calcium (CaV Channels

    Directory of Open Access Journals (Sweden)

    David Ramírez

    2017-10-01

    Full Text Available Voltage-gated calcium (CaV channels are widely expressed and are essential for the completion of multiple physiological processes. Close regulation of their activity by specific inhibitors and agonists become fundamental to understand their role in cellular homeostasis as well as in human tissues and organs. CaV channels are divided into two groups depending on the membrane potential required to activate them: High-voltage activated (HVA, CaV1.1–1.4; CaV2.1–2.3 and Low-voltage activated (LVA, CaV3.1–3.3. HVA channels are highly expressed in brain (neurons, heart, and adrenal medulla (chromaffin cells, among others, and are also classified into subtypes which can be distinguished using pharmacological approaches. Cone snails are marine gastropods that capture their prey by injecting venom, “conopeptides”, which cause paralysis in a few seconds. A subset of conopeptides called conotoxins are relatively small polypeptides, rich in disulfide bonds, that target ion channels, transporters and receptors localized at the neuromuscular system of the animal target. In this review, we describe the structure and properties of conotoxins that selectively block HVA calcium channels. We compare their potency on several HVA channel subtypes, emphasizing neuronal calcium channels. Lastly, we analyze recent advances in the therapeutic use of conotoxins for medical treatments.

  15. Recent advances in the understanding of how neuropeptide Y andα-melanocyte stimulating hormone function in adipose physiology.

    Science.gov (United States)

    Shipp, Steven L; Cline, Mark A; Gilbert, Elizabeth R

    2016-01-01

    Communication between the brain and the adipose tissue has been the focus of many studies in recent years, with the "brain-fat axis" identified as a system that orchestrates the assimilation and usage of energy to maintain body mass and adequate fat stores. It is now well-known that appetite-regulating peptides that were studied as neurotransmitters in the central nervous system can act both on the hypothalamus to regulate feeding behavior and also on the adipose tissue to modulate the storage of energy. Energy balance is thus partly controlled by factors that can alter both energy intake and storage/expenditure. Two such factors involved in these processes are neuropeptide Y (NPY) and α-melanocyte stimulating hormone (α-MSH). NPY, an orexigenic factor, is associated with promoting adipogenesis in both mammals and chickens, while α-MSH, an anorexigenic factor, stimulates lipolysis in rodents. There is also evidence of interaction between the 2 peptides. This review aims to summarize recent advances in the study of NPY and α-MSH regarding their role in adipose tissue physiology, with an emphasis on the cellular and molecular mechanisms. A greater understanding of the brain-fat axis and regulation of adiposity by bioactive peptides may provide insights on strategies to prevent or treat obesity and also enhance nutrient utilization efficiency in agriculturally-important species.

  16. Understanding the Combined Influence of Boreal Landuse and Climate Change on Catchment Functioning through Virtual Forest Alterations

    Science.gov (United States)

    Teutschbein, Claudia; Grabs, Thomas; Karlsen, Reinert H.; Laudon, Hjalmar; Bishop, Kevin

    2017-04-01

    The available scientific literature on hydrological climate change impacts in boreal regions in northern Europe consistently suggests increasing amounts of annual river streamflow. In these regions, the present-day streamflow regimes with low winter flow and a dominating snow-melt driven spring flood peak will transform to regimes with a much lower amplitude and an earlier initiation and peaking of the spring flood. Such changes lead to alterations of flow duration curves, indicating lower chances for both high and low flows in a future warmer climate. The question arises as to whether one can draw such generalized conclusions in terms of future hydrological changes for a larger boreal region based on a selection of representative catchment studies. One could argue that nearby catchments within the same climate zone should function in similar ways, which means that conclusions can be drawn for a larger region with the same climate conditions. It is, however, well acknowledged that present-day hydrological functioning and the variability at multiple temporal and spatial scales are not only controlled by external climatic conditions, but also by physical properties such as topographic features, soil characteristics, catchment area, land cover, vegetation type or geology. Consequently, this raises the question as to what extend variability in projected future streamflow changes is predetermined by the landscape characteristics in a catchment. To answer this question, we explored how landscape characteristics such as topography, geology, soils and land cover influence the way boreal catchments respond to changing climate conditions. Based on an ensemble of 15 regional climate models bias-corrected with a distribution-mapping approach, present and future streamflow in 14 neighbouring and rather similar catchments in Northern Sweden was simulated with the HBV model. We established functional relationships between a range of landscape characteristics and projected future

  17. Understanding Catalytic Activity Trends for NO Decomposition and CO Oxidation using Density Functional Theory and Microkinetic Modeling

    DEFF Research Database (Denmark)

    Falsig, Hanne

    towards rationalizing trends in catalytic activity of transition metal catalysts for NO decomposition by combining microkinetic modelling with density functional theory calculations. We establish the full potential energy diagram for the direct NO decomposition reaction over stepped transition...... and Pt are the best direct NO decomposition catalysts among the 3d, 4d, and 5d metals. We analyze the NO decomposition reaction in terms of the Sabatier analysis and a Sabatier–Gibbs-type analysis and obtain an activity trend in agreement with experimental results. We show specifically why the key...... problem in using transition metal surfaces to catalyze direct NO decomposition is their significant relative overbinding of atomic oxygen compared to atomic nitrogen. We calculate adsorption and transition state energies for the full CO oxidation reaction pathway by the use of DFT for a number...

  18. Phage Endolysin: A Way To Understand A Binding Function Of C-Terminal Domains A Mini Review

    Directory of Open Access Journals (Sweden)

    Jarábková Veronika

    2015-12-01

    Full Text Available Endolysins are bacteriophage-encoded peptidoglycan hydrolases, which are synthesized in the end of phage reproduction cycle, in an infected host cell. Usually, for endolysins from phages that infect Gram-positive bacteria, a modular structure is typical. Therefore, these are composed of at least two separate functional domains: an N-terminal catalytic domain (EAD and a C-terminal cell wall binding domain (CBD. Specific ligand recognition of CBDs and following peptidoglycan (PG binding mostly allows a rapid lytic activity of an EAD. Here we briefly characterize phage endolysin CBDs in conjuction with their domain architecture, (nonnecessity for the following lytic activity and a high/low specificity of their ligands as well. Such an overall assessment of CBDs may help to find new ways to widen opportunities in their protein design to create ‛designer recombinant endolysins’ with diverse applications.

  19. Resistance Switching in Complex Oxides: Improvements in Understanding and Function for Use as Non-Volatile Memory

    Science.gov (United States)

    Young, Kristina Garrison

    2011-12-01

    Pro0.7Ca0.3MnO3 (PCMO) is a complex oxide that is studied for use as a non-volatile memory with potential to replace flash-type memory. PCMO functions as a resistive random access memory (RRAM) whose memory function is due to an oxygen vacancy concentration change that occurs in the top interface of the PCMO during the application of an electric field. The concentration of the oxygen ions/vacancies in this top interface region significantly affects the resistance seen in a simple thin film device. The electric field required to move ions/vacancies within PCMO is generated by a short (ns), low voltage (few V) pulse. During the pulse a high current is seen that is not commensurate with the resistance seen after the removal of the pulse. Additionally, after the removal of the pulse there is a degradation of the resistance state set by the pulse. The high current seen during the pulse has been explored using electrical characterization techniques and is believed to be due to quantum mechanical tunneling through the high resistance interface region. Modeling of conduction values confirms that quantum mechanical tunneling is the source of the high current. The degradation of the state after the removal of the pulse has been improved through the nanostructure modification of the PCMO film. A thin (barrier layer was placed immediately below the interface of the PCMO minimizing the back diffusion of ions/vacancies after removal of the pulse. The modification improved the EPIR ratio, fatigue and retention in PCMO.

  20. [Current status and understandings in function-preserving gastrectomy under the concept of minimally invasive surgery in China, South Korea and Japan].

    Science.gov (United States)

    Zhao, Enhao; Zhao, Gang; Cao, Hui

    2018-02-25

    In the past few years, the early detection of gastric cancer has increased in China. The surgical treatment for early gastric cancer has gradually transformed from conventional gastrectomy with D2 lymphadenectomy to function-preserving gastrectomy which maximally preserves the anatomy and physiology of stomach to maintain the quality of life of the patient. Driven by minimally invasive techniques, function-preserving gastrectomies, including pylorus-preserving gastrectomy, proximal gastrectomy, sentinel node navigation surgery, etc. have already gained great attention especially in Japan and Korea. Although there are still many unsolved problems that need to be further discussed and explored, understanding of the clinical features of early gastric cancer and definition of gastric function preservation, launching clinical trials for solving practical problems, and emphasis of individualized and precision treatment will be the best strategies to improve the efficacy of early gastric cancer.

  1. Understanding the cognitive and genetic underpinnings of procrastination: Evidence for shared genetic influences with goal management and executive function abilities.

    Science.gov (United States)

    Gustavson, Daniel E; Miyake, Akira; Hewitt, John K; Friedman, Naomi P

    2015-12-01

    Previous research has suggested that individual differences in procrastination are tied to everyday goal-management abilities, but little research has been conducted on specific cognitive abilities that may underlie tendencies for procrastination, such as executive functions (EFs). In this study, we used behavioral genetics methodology to investigate 2 hypotheses about the relationships between procrastination and EF ability: (a) that procrastination is negatively correlated with general EF ability, and (b) that this relationship is due to the genetic components of procrastination that are most related to other everyday goal-management abilities. The results confirmed both of these hypotheses. Procrastination was related to worse general EF ability at both the phenotypic and genetic levels, and this relationship was due to the component of procrastination shared with self-report measures of everyday goal-management failures. These results were observed even after controlling for potential self-report biases stemming from the urge to respond in a socially desirable manner. Together, these findings provide strong evidence for growing theories of procrastination emphasizing the importance of goal-related cognitive abilities and further highlight important genetic influences that underlie procrastination. (c) 2015 APA, all rights reserved).

  2. Functional brain imaging: what has it brought to our understanding of neuropathic pain? A special focus on allodynic pain mechanisms.

    Science.gov (United States)

    Peyron, Roland

    2016-02-01

    Brain responses to nociception are well identified. The same is not true for allodynic pain, a strong painful sensation in response to touch or innocuous cold stimuli that may be experienced by patients with neuropathic pain. Brain (or spinal cord) reorganization that may explain this paradoxical perception still remains largely unknown. Allodynic pain is associated with abnormally increased activity in SII and in the anterior insular cortex, contralateral and/or ipsilateral to allodynia. Because a bilateral increase in activity has been repeatedly reported in these areas in nociceptive conditions, the observed activation during allodynia can explain that a physiologically nonpainful stimulus could be perceived by the damaged nervous system as a painful one. Both secondary somatosensory and insular cortices receive input from the thalamus, which is a major relay of sensory and spinothalamic pathways, the involvement of which is known to be crucial for the development of neuropathic pain. Both thalamic function and structure have been reported to be abnormal or impaired in neuropathic pain conditions including in the basal state, possibly explaining the spontaneous component of neuropathic pain. A further indication as to how the brain can create neuropathic pain response in SII and insular cortices stems from examples of diseases, including single-case reports in whom a focal brain lesion leads to central pain disappearance. Additional studies are required to certify the contribution of these areas to the disease processes, to disentangle abnormalities respectively related to pain and to deafferentation, and, in the future, to guide targeting of stimulation studies.

  3. Cortical and white matter mapping in the visual system- more than meets theeye: on the importance of functional imaging to understand visual systempathologies

    Directory of Open Access Journals (Sweden)

    Noa eRaz

    2014-08-01

    Full Text Available Information transmission within the visual system is highly organized with the ultimate goal of accomplishing higher-order, complex visuo-spatial and object identity processing. Perception is dependent on the intactness of the entire system and damage at each stage – in the eye itself, the visual pathways, or within cortical processing - might result in perception disturbance.Herein we will review several examples of lesions along the visual system, from the retina, via the optic nerve and chiasm and through the occipital cortex. We will address their clinical manifestation and their cortical substrate. The latter will be studied via functional magnetic resonance imaging (fMRI and Diffusion Tensor Imaging (DTI, enabling cortical and white matter mapping of the human brain. In contrast to traditional signal recording, these procedures enable simultaneous evaluation of the entire brain network engaged when subjects undertake a particular task or evaluate the entirety of associated white matter pathways.These examples provided will highlight the importance of using advanced imaging methods to better understand visual pathologies. We will argue that clinical manifestation cannot always be explained solely by structural damage and a functional view is required to understand the clinical symptom. In such cases we recommend using advanced imaging methods to better understand the neurological basis of visual phenomena.

  4. Neural stem cells and neuro/gliogenesis in the central nervous system: understanding the structural and functional plasticity of the developing, mature, and diseased brain.

    Science.gov (United States)

    Yamaguchi, Masahiro; Seki, Tatsunori; Imayoshi, Itaru; Tamamaki, Nobuaki; Hayashi, Yoshitaka; Tatebayashi, Yoshitaka; Hitoshi, Seiji

    2016-05-01

    Neurons and glia in the central nervous system (CNS) originate from neural stem cells (NSCs). Knowledge of the mechanisms of neuro/gliogenesis from NSCs is fundamental to our understanding of how complex brain architecture and function develop. NSCs are present not only in the developing brain but also in the mature brain in adults. Adult neurogenesis likely provides remarkable plasticity to the mature brain. In addition, recent progress in basic research in mental disorders suggests an etiological link with impaired neuro/gliogenesis in particular brain regions. Here, we review the recent progress and discuss future directions in stem cell and neuro/gliogenesis biology by introducing several topics presented at a joint meeting of the Japanese Association of Anatomists and the Physiological Society of Japan in 2015. Collectively, these topics indicated that neuro/gliogenesis from NSCs is a common event occurring in many brain regions at various ages in animals. Given that significant structural and functional changes in cells and neural networks are accompanied by neuro/gliogenesis from NSCs and the integration of newly generated cells into the network, stem cell and neuro/gliogenesis biology provides a good platform from which to develop an integrated understanding of the structural and functional plasticity that underlies the development of the CNS, its remodeling in adulthood, and the recovery from diseases that affect it.

  5. Nuclear inelastic scattering and density-functional-theory calculations on the understanding of the vibronic properties of polynuclear iron complexes

    International Nuclear Information System (INIS)

    Faus, Isabelle

    2015-01-01

    Transition metal complexes of 3d elements with an electronic configuration of d 4 to d 8 can show a temperature dependent spin transition. This process is called spin crossover (SCO) effect and describes the transition between two states, the low spin (LS) state and the high spin (HS) state. In the LS state the spin is as low as possible, caused by none or a minimal number of unpaired electrons. In the HS state the spin is as high as possible with a maximal number of unpaired electrons. Because of this bistability, SCO materials are promising candidates for innovative molecular storage devices. Directly related to the SCO effect is the cooperativity, which specifies the interaction of metal centers between molecules (intermolecular cooperativity) or in a molecule (intramolecular cooperativity). Cooperativity is of vital importance for the switching behavior of SCO complexes with broad hysteresis. Therefore, three dinuclear SCO complexes which show a varying degree of cooperativity due to different geometries of their bridging ligands were investigated. By means of nuclear inelastic scattering (NIS), it could be clarified whether it is possible to find intramolecular cooperative effects in the vibrational patterns of these complexes. With corresponding density functional theory (DFT) calculations, it was possible for all of the dinuclear complexes to correlate the experimental NIS bands to the corresponding molecular vibrational modes. In the LS-LS or HS-HS state of the three complexes two modes exist lying energetically close together, which show a similar movement of the whole complex, with only a difference in the movement of the iron atoms. Thereby, the irons are moving either in the same or in the opposite direction. For complexes with a high degree of cooperativity there are nearly exclusively small energy shifts between this kind of nearly twofold energetically degenerated modes (ΔE <7 cm -1 ), for the complex with a low degree of cooperativity there are

  6. Transgenic Mouse Studies to Understand the Regulation, Expression and Function of the Testis-Specific Protein Y-Encoded (TSPY Gene

    Directory of Open Access Journals (Sweden)

    Stephanie Schubert

    2010-08-01

    Full Text Available The TSPY gene, which encodes the testis-specific protein, Y-encoded, was first discovered and characterized in humans, but orthologous genes were subsequently identified on the Y chromosome of many other placental mammals. TSPY is expressed in the testis and to a much lesser extent in the prostate gland, and it is assumed that TSPY serves function in spermatogonial proliferation and/or differentiation. It is further supposed that TSPY is involved in male infertility and exerts oncogenic effects in gonadal and prostate tumor formation. As a member of the TSPY/SET/NAP protein family, TSPY is able to bind cyclin B types, and stimulates the cyclin B1-CDK1 kinase activity, thereby accelerating the G2/M phase transition of the cell cycle of target cells. Because the laboratory mouse carries only a nonfunctional Y-chromosomal Tspy-ps pseudogene, a knockout mouse model for functional research analyses is not a feasible approach. In the last decade, three classical transgenic mouse models have been developed to contribute to our understanding of TSPY regulation, expression and function. The different transgenic mouse approaches and their relevance for studying TSPY regulation, expression and function are discussed in this review.

  7. Understanding analysis

    CERN Document Server

    Abbott, Stephen

    2015-01-01

    This lively introductory text exposes the student to the rewards of a rigorous study of functions of a real variable. In each chapter, informal discussions of questions that give analysis its inherent fascination are followed by precise, but not overly formal, developments of the techniques needed to make sense of them. By focusing on the unifying themes of approximation and the resolution of paradoxes that arise in the transition from the finite to the infinite, the text turns what could be a daunting cascade of definitions and theorems into a coherent and engaging progression of ideas. Acutely aware of the need for rigor, the student is much better prepared to understand what constitutes a proper mathematical proof and how to write one. Fifteen years of classroom experience with the first edition of Understanding Analysis have solidified and refined the central narrative of the second edition. Roughly 150 new exercises join a selection of the best exercises from the first edition, and three more project-sty...

  8. High-speed imaging and small-scale explosive characterization techniques to understand effects of primary blast-induced injury on nerve cell structure and function

    Science.gov (United States)

    Piehler, T.; Banton, R.; Zander, N.; Duckworth, J.; Benjamin, R.; Sparks, R.

    2018-01-01

    Traumatic brain injury (TBI) is often associated with blast exposure. Even in the absence of penetrating injury or evidence of tissue injury on imaging, blast TBI may trigger a series of neural/glial cellular and functional changes. Unfortunately, the diagnosis and proper treatment of mild traumatic brain injury (mTBI) caused by explosive blast is challenging, as it is not easy to clinically distinguish blast from non-blast TBI on the basis of patient symptoms. Damage to brain tissue, cell, and subcellular structures continues to occur slowly and in a manner undetectable by conventional imaging techniques. The threshold shock impulse levels required to induce damage and the cumulative effects upon multiple exposures are not well characterized. Understanding how functional and structural damage from realistic blast impact at cellular and tissue levels at variable timescales after mTBI events may be vital for understanding this injury phenomenon and for linking mechanically induced structural changes with measurable effects on the nervous system. Our working hypothesis is that there is some transient physiological dysfunction occurring at cellular and subcellular levels within the central nervous system due to primary blast exposure. We have developed a novel in vitro indoor experimental system that uses real military explosive charges to more accurately represent military blast exposure and to probe the effects of primary explosive blast on dissociated neurons. We believe this system offers a controlled experimental method to analyze and characterize primary explosive blast-induced cellular injury and to understand threshold injury phenomenon. This paper will also focus on the modeling aspect of our work and how it relates to the experimental work.

  9. Understanding and controlling hepatobiliary function

    NARCIS (Netherlands)

    Elferink, Ronald P. J. Oude

    2002-01-01

    Over the past decade, enormous progress has been made in identifying the mechanisms that underlie hepatobiliary excretion. A set of transport proteins mediates the canalicular transport of most important bile constituents. With the discovery of these transporter genes, the mechanism of bile

  10. A Continental-scale River Corridor Model to Synthesize Understanding and Prioritize Management of Water Purification Functions and Ecological Services in Large Basins

    Science.gov (United States)

    Harvey, J. W.; Gomez-Velez, J. D.; Scott, D.; Boyer, E. W.; Schmadel, N. M.; Alexander, R. B.; Eng, K.; Golden, H. E.; Kettner, A.; Konrad, C. P.; Moore, R. B.; Pizzuto, J. E.; Schwarz, G. E.; Soulsby, C.

    2017-12-01

    The functional values of rivers depend on more than just wetted river channels. Instead, the river channel exchanges water and suspended materials with adjacent riparian, floodplain, hyporheic zones, and ponded waters such as lakes and reservoirs. Together these features comprise a larger functional unit known as the river corridor. The exchange of water, solutes, and sediments within the river corridor alters downstream water quality and ecological functions, but our understanding of the large-scale, cumulative impacts is inadequate and has limited advancements in sustainable management practices. A problem with traditional watershed, groundwater, and river water quality models is that none of them explicitly accounts for river corridor storage and processing, and the exchanges of water, solutes, and sediments that occur many times between the channel and off-channel environments during a river's transport to the sea. Our River Corridor Working Group at the John Wesley Powell Center is quantifying the key components of river corridor functions. Relying on foundational studies that identified floodplain, riparian, and hyporheic exchange flows and resulting enhancement of chemical reactions at river reach scales, we are assembling the datasets and building the models to upscale that understanding onto 2.6 million river reaches in the U.S. A principal goal of the River Corridor Working group is to develop a national-scale river corridor model for the conterminous U.S. that will reveal, perhaps for the first time, the relative influences of hyporheic, riparian, floodplain, and ponded waters at large spatial scales. The simple but physically-based models are predictive for changing conditions and therefore can directly address the consequences and effectiveness of management actions in sustaining valuable river corridor functions. This presentation features interpretation of useful river corridor connectivity metrics and ponded water influences on nutrient and sediment

  11. Conservation and function of Rab small GTPases in Entamoeba: annotation of E. invadens Rab and its use for the understanding of Entamoeba biology.

    Science.gov (United States)

    Nakada-Tsukui, Kumiko; Saito-Nakano, Yumiko; Husain, Afzal; Nozaki, Tomoyoshi

    2010-11-01

    Entamoeba invadens is a reptilian enteric protozoan parasite closely related to the human pathogen Entamoeba histolytica and a good model organism of encystation. To understand the molecular mechanism of vesicular trafficking involved in the encystation of Entamoeba, we examined the conservation of Rab small GTPases between the two species. E. invadens has over 100 Rab genes, similar to E. histolytica. Most of the Rab subfamilies are conserved between the two species, while a number of species-specific Rabs are also present. We annotated all E. invadens Rabs according to the previous nomenclature [Saito-Nakano, Y., Loftus, B.J., Hall, N., Nozaki, T., 2005. The diversity of Rab GTPases in Entamoeba histolytica. Experimental Parasitology 110, 244-252]. Comparative genomic analysis suggested that the fundamental vesicular traffic machinery is well conserved, while there are species-specific protein transport mechanisms. We also reviewed the function of Rabs in Entamoeba, and proposed the use of the annotation of E. invadens Rab genes to understand the ubiquitous importance of Rab-mediated membrane trafficking during important biological processes including differentiation in Entamoeba. (c) 2010 Elsevier Inc. All rights reserved.

  12. Understanding Carbohydrates

    Science.gov (United States)

    ... Size: A A A Listen En Español Understanding Carbohydrates How much and what type of carbohydrate foods ... glucose levels in your target range. Explore: Understanding Carbohydrates Glycemic Index and Diabetes Learn about the glycemic ...

  13. Functional morphology of parasitic isopods: understanding morphological adaptations of attachment and feeding structures in Nerocila as a pre-requisite for reconstructing the evolution of Cymothoidae

    Directory of Open Access Journals (Sweden)

    Christina Nagler

    2016-07-01

    Full Text Available Parasites significantly influence food webs and ecosystems and occur all over the world in almost every animal group. Within crustaceans there are numerous examples of ectoparasites; for example, representatives of the isopod group Cymothoidae. These obligatory parasitic isopods are relatively poorly studied regarding their functional morphology. Here we present new details of the morphological adaptations to parasitism of the cymothoiid ingroup Nerocila with up-to-date imaging methods (macro photography, stereo imaging, fluorescence photography, micro CT, and histology. Central aspects of the study were (1 the morphology of the mouthparts and (2 the attachment on the host, hence the morphology of the thoracopods. The mouthparts (labrum, mandibles, paragnaths, maxillulae, maxillae, maxillipeds form a distinct mouth cone and are most likely used for true sucking. The mouthparts are tightly “folded” around each other and provide functional rails for the only two moving mouthparts, mandible and maxillula. Both are not moving in an ancestral-type median-lateral movement, but are strongly tilted to move more in a proximal-distal axis. New details concerning the attachment demonstrate that the angular arrangement of the thoracopods is differentiated to impede removal by the host. The increased understanding of morphological adaptation to parasitism of modern forms will be useful in identifying disarticulated (not attached to the host fossil parasites.

  14. dbSWEET: An Integrated Resource for SWEET Superfamily to Understand, Analyze and Predict the Function of Sugar Transporters in Prokaryotes and Eukaryotes.

    Science.gov (United States)

    Gupta, Ankita; Sankararamakrishnan, Ramasubbu

    2018-04-14

    SWEET (Sweet Will Eventually be Exported Transporter) proteins have been recently discovered and form one of the three major families of sugar transporters. Homologs of SWEET are found in both prokaryotes and eukaryotes. Bacterial SWEET homologs have three transmembrane segments forming a triple-helical bundle (THB) and the functional form is dimers. Eukaryotic SWEETs have seven transmembrane helical segments forming two THBs with a linker helix. Members of SWEET homologs have been shown to be involved in several important physiological processes in plants. However, not much is known regarding the biological significance of SWEET homologs in prokaryotes and in mammals. We have collected more than 2000 SWEET homologs from both prokaryotes and eukaryotes. For each homolog, we have modeled three different conformational states representing outward open, inward open and occluded states. We have provided details regarding substrate-interacting residues and residues forming the selectivity filter for each SWEET homolog. Several search and analysis options are available. The users can generate a phylogenetic tree and structure-based sequence alignment for selected set of sequences. With no metazoan SWEETs functionally characterized, the features observed in the selectivity filter residues can be used to predict the potential substrates that are likely to be transported across the metazoan SWEETs. We believe that this database will help the researchers to design mutational experiments and simulation studies that will aid to advance our understanding of the physiological role of SWEET homologs. This database is freely available to the scientific community at http://bioinfo.iitk.ac.in/bioinfo/dbSWEET/Home. Copyright © 2018. Published by Elsevier Ltd.

  15. Resources, attitudes and culture: an understanding of the factors that influence the functioning of accountability mechanisms in primary health care settings.

    Science.gov (United States)

    Cleary, Susan M; Molyneux, Sassy; Gilson, Lucy

    2013-08-16

    District level health system governance is recognised as an important but challenging element of health system development in low and middle-income countries. Accountability is a more recent focus in health system debates. Accountability mechanisms are governance tools that seek to regulate answerability between the health system and the community (external accountability) and/or between different levels of the health system (bureaucratic accountability). External accountability has attracted significant attention in recent years, but bureaucratic accountability mechanisms, and the interactions between the two forms of accountability, have been relatively neglected. This is an important gap given that webs of accountability relationships exist within every health system. There is a need to strike a balance between achieving accountability upwards within the health system (for example through information reporting arrangements) while at the same time allowing for the local level innovation that could improve quality of care and patient responsiveness. Using a descriptive literature review, this paper examines the factors that influence the functioning of accountability mechanisms and relationships within the district health system, and draws out the implications for responsiveness to patients and communities. We also seek to understand the practices that might strengthen accountability in ways that improve responsiveness--of the health system to citizens' needs and rights, and of providers to patients. The review highlights the ways in which bureaucratic accountability mechanisms often constrain the functioning of external accountability mechanisms. For example, meeting the expectations of relatively powerful managers further up the system may crowd out efforts to respond to citizens and patients. Organisational cultures characterized by supervision and management systems focused on compliance to centrally defined outputs and targets can constrain front line

  16. Memorandum of Understanding.

    Energy Technology Data Exchange (ETDEWEB)

    Siple, Bud H. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)

    2014-07-01

    A Memorandum of Understanding establishes a clear understanding of how an agreement is going to be implemented. The Memorandum of Understanding allows all involved to specifically understand that they are agreeing to the same thing and the terms are clearly identified. It also includes the clear distinction of functions and the level of involvement of the agencies involved. Specifically, a Memorandum of Understanding gives a chance to all of those involved in the agreement to see on paper as to what they all have agreed to.

  17. The hot pepper (Capsicum annuum microRNA transcriptome reveals novel and conserved targets: a foundation for understanding MicroRNA functional roles in hot pepper.

    Directory of Open Access Journals (Sweden)

    Dong-Gyu Hwang

    Full Text Available MicroRNAs (miRNAs are a class of non-coding RNAs approximately 21 nt in length which play important roles in regulating gene expression in plants. Although many miRNA studies have focused on a few model plants, miRNAs and their target genes remain largely unknown in hot pepper (Capsicum annuum, one of the most important crops cultivated worldwide. Here, we employed high-throughput sequencing technology to identify miRNAs in pepper extensively from 10 different libraries, including leaf, stem, root, flower, and six developmental stage fruits. Based on a bioinformatics pipeline, we successfully identified 29 and 35 families of conserved and novel miRNAs, respectively. Northern blot analysis was used to validate further the expression of representative miRNAs and to analyze their tissue-specific or developmental stage-specific expression patterns. Moreover, we computationally predicted miRNA targets, many of which were experimentally confirmed using 5' rapid amplification of cDNA ends analysis. One of the validated novel targets of miR-396 was a domain rearranged methyltransferase, the major de novo methylation enzyme, involved in RNA-directed DNA methylation in plants. This work provides the first reliable draft of the pepper miRNA transcriptome. It offers an expanded picture of pepper miRNAs in relation to other plants, providing a basis for understanding the functional roles of miRNAs in pepper.

  18. A Phytochemical-Sensing Strategy Based on Mass Spectrometry Imaging and Metabolic Profiling for Understanding the Functionality of the Medicinal Herb Green Tea

    Directory of Open Access Journals (Sweden)

    Yoshinori Fujimura

    2017-09-01

    Full Text Available Low-molecular-weight phytochemicals have health benefits and reduce the risk of diseases, but the mechanisms underlying their activities have remained elusive because of the lack of a methodology that can easily visualize the exact behavior of such small molecules. Recently, we developed an in situ label-free imaging technique, called mass spectrometry imaging, for visualizing spatially-resolved biotransformations based on simultaneous mapping of the major bioactive green tea polyphenol and its phase II metabolites. In addition, we established a mass spectrometry-based metabolic profiling technique capable of evaluating the bioactivities of diverse green tea extracts, which contain multiple phytochemicals, by focusing on their compositional balances. This methodology allowed us to simultaneously evaluate the relative contributions of the multiple compounds present in a multicomponent system to its bioactivity. This review highlights small molecule-sensing techniques for visualizing the complex behaviors of herbal components and linking such information to an enhanced understanding of the functionalities of multicomponent medicinal herbs.

  19. From bacterial avirulence genes to effector functions via the hrp delivery system: an overview of 25 years of progress in our understanding of plant innate immunity.

    Science.gov (United States)

    Mansfield, John W

    2009-11-01

    Cloning the first avirulence (avr) gene has led not only to a deeper understanding of gene-for-gene interactions in plant disease, but also to fundamental insights into the suppression of basal defences against microbial attack. This article (focusing on Pseudomonas syringae) charts the development of ideas and research progress over the 25 years following the breakthrough achieved by Staskawicz and coworkers. Advances in gene cloning technology underpinned the identification of both avr and hrp genes, the latter being required for the activation of the defensive hypersensitive reaction (HR) and pathogenicity. The delivery of Avr proteins through the type III secretion machinery encoded by hrp gene clusters was demonstrated, and the activity of the proteins inside plant cells as elicitors of the HR was confirmed. Key roles for avr genes in pathogenic fitness have now been established. The rebranding of Avr proteins as effectors, proteins that suppress the HR and cell wall-based defences, has led to the ongoing search for their targets, and is generating new insights into the co-ordination of plant resistance against diverse microbes. Bioinformatics-led analysis of effector gene distribution in genomes has provided a remarkable view of the interchange of effectors and also their functional domains, as the arms race of attack and defence drives the evolution of microbial pathogenicity. The application of our accrued knowledge for the development of disease control strategies is considered.

  20. Using Plant Functional Traits and Phylogenies to Understand Patterns of Plant Community Assembly in a Seasonal Tropical Forest in Lao PDR.

    Directory of Open Access Journals (Sweden)

    Manichanh Satdichanh

    Full Text Available Plant functional traits reflect different evolutionary responses to environmental variation, and among extant species determine the outcomes of interactions between plants and their environment, including other plant species. Thus, combining phylogenetic and trait-based information can be a powerful approach for understanding community assembly processes across a range of spatial scales. We used this approach to investigate tree community composition at Phou Khao Khouay National Park (18°14'-18°32'N; 102°38'- 102°59'E, Laos, where several distinct forest types occur in close proximity. The aim of our study was to examine patterns of plant community assembly across the strong environmental gradients evident at our site. We hypothesized that differences in tree community composition were being driven by an underlying gradient in soil conditions. Thus, we predicted that environmental filtering would predominate at the site and that the filtering would be strongest on sandier soil with low pH, as these are the conditions least favorable to plant growth. We surveyed eleven 0.25 ha (50x50 m plots for all trees above 10 cm dbh (1221 individual trees, including 47 families, 70 genera and 123 species and sampled soils in each plot. For each species in the community, we measured 11 commonly studied plant functional traits covering both the leaf and wood economic spectrum traits and we reconstructed a phylogenetic tree for 115 of the species in the community using rbcL and matK sequences downloaded from Genebank (other species were not available. Finally we compared the distribution of trait values and species at two scales (among plots and 10x10m subplots to examine trait and phylogenetic community structures. Although there was strong evidence that an underlying soil gradient was determining patterns of species composition at the site, our results did not support the hypothesis that the environmental filtering dominated community assembly processes

  1. Understanding classification

    NARCIS (Netherlands)

    Subianto, M.

    2009-01-01

    In practical data analysis, the understandability of models plays an important role in their acceptance. In the data mining literature, however, understandability plays is hardly ever mentioned. If it is mentioned, it is interpreted as meaning that the models have to be simple. In this thesis we

  2. Embodied understanding.

    Science.gov (United States)

    Johnson, Mark

    2015-01-01

    Western culture has inherited a view of understanding as an intellectual cognitive operation of grasping of concepts and their relations. However, cognitive science research has shown that this received intellectualist conception is substantially out of touch with how humans actually make and experience meaning. The view emerging from the mind sciences recognizes that understanding is profoundly embodied, insofar as our conceptualization and reasoning recruit sensory, motor, and affective patterns and processes to structure our understanding of, and engagement with, our world. A psychologically realistic account of understanding must begin with the patterns of ongoing interaction between an organism and its physical and cultural environments and must include both our emotional responses to changes in our body and environment, and also the actions by which we continuously transform our experience. Consequently, embodied understanding is not merely a conceptual/propositional activity of thought, but rather constitutes our most basic way of being in, and engaging with, our surroundings in a deep visceral manner.

  3. Understanding semantics

    DEFF Research Database (Denmark)

    Thrane, Torben

    1997-01-01

    Understanding natural language is a cognitive, information-driven process. Discussing some of the consequences of this fact, the paper offers a novel look at the semantic effect of lexical nouns and the identification of reference types....

  4. Understanding Alzheimer's

    Science.gov (United States)

    ... Navigation Bar Home Current Issue Past Issues Understanding Alzheimer's Past Issues / Fall 2007 Table of Contents For ... and brain scans. No treatment so far stops Alzheimer's. However, for some in the disease's early and ...

  5. Understanding homelessness

    OpenAIRE

    Somerville, Peter

    2013-01-01

    This paper reviews the literature on understanding homelessness. It criticizes approaches that ignore, distort or diminish the humanity of homeless people, or else, add little to our understanding of that humanity. In particular, it rejects what it calls “epidemiological” approaches, which deny the possibility of agency for homeless people, insofar as those approaches view the situation of those people largely as a “social fact”, to be explained in terms of causal variables or “risk factors” ...

  6. Receiver function and magnetotelluric analysis to understand the first stage of a continental lithospheric break-up : case of the North Tanzanian Rift

    Science.gov (United States)

    Plasman, M.; Tiberi, C.; Tarits, P.; Hautot, S.; Gautier, S.; Ebinger, C. J.; Mulibo, G. D.; Khalfan, M.

    2015-12-01

    First stage of continental break-up, though intensively studied, is yet poorly understood. This is partly because actual rifting areas are either too mature (more than 10 My) or not easily accessible (thick sediment cover or under water). The North Tanzania part of the East African Rift is the place of a lithosphere's early break-up (less than 5My) in response to a combination of regional pulling forces and mantle upwelling. Deformation there results from complex interactions between magmatic intrusions, faulting, asthenospheric dynamics and far field stresses. CoLiBrEA (ANR) and CRAFTI (NSF) are two multidisciplinary projects which collaboratively focus on this area to understand the interactions between faults and magma, the role of inherited structures and rheological heterogeneities of the lithosphere. For that purpose, we deployed 38 broadband seismic stations in the Natron and Ngorongoro areas from January 2013 to December 2014 and carried out a 120 km East-West magnetotelluric (MT) profile to image the crustal and mantle structures. The 3D resistivity model, obtained from the inversion of the MT data along the profile, shows an highly heterogeneous crust with three-dimensional structures over a more homogeneous upper mantle. The first inversion result from the receiver function (RF) by the Zhu and Kanamori's inversion method show a thick crust (~35 km) with important variations (maximum 15km) especially in the Ngorongoro area, and an average Vp/Vs ratio of 1.75. We then completed this study by combining the MT data and the RF at the 11 sites of the EW profile. For each site, we built a 1D velocity model (Vs and VpVs) obtained by combining the Sambridge forward solution with a non linear descent research algorithm and constrained by the resistivity structure. The inversion shows an heterogeneous crust obviously dominated by the Moho interface at different depths, with low velocity layers mainly corresponding to low resistivity features.

  7. Understanding Maple

    CERN Document Server

    Thompson, Ian

    2016-01-01

    Maple is a powerful symbolic computation system that is widely used in universities around the world. This short introduction gives readers an insight into the rules that control how the system works, and how to understand, fix, and avoid common problems. Topics covered include algebra, calculus, linear algebra, graphics, programming, and procedures. Each chapter contains numerous illustrative examples, using mathematics that does not extend beyond first-year undergraduate material. Maple worksheets containing these examples are available for download from the author's personal website. The book is suitable for new users, but where advanced topics are central to understanding Maple they are tackled head-on. Many concepts which are absent from introductory books and manuals are described in detail. With this book, students, teachers and researchers will gain a solid understanding of Maple and how to use it to solve complex mathematical problems in a simple and efficient way.

  8. Understanding physics

    CERN Document Server

    Mansfield, Michael

    2011-01-01

    Understanding Physics - Second edition is a comprehensive, yet compact, introductory physics textbook aimed at physics undergraduates and also at engineers and other scientists taking a general physics course. Written with today's students in mind, this text covers the core material required by an introductory course in a clear and refreshing way. A second colour is used throughout to enhance learning and understanding. Each topic is introduced from first principles so that the text is suitable for students without a prior background in physics. At the same time the book is designed to enable

  9. Understanding Energy

    Science.gov (United States)

    Menon, Deepika; Shelby, Blake; Mattingly, Christine

    2016-01-01

    "Energy" is a term often used in everyday language. Even young children associate energy with the food they eat, feeling tired after playing soccer, or when asked to turn the lights off to save light energy. However, they may not have the scientific conceptual understanding of energy at this age. Teaching energy and matter could be…

  10. Understanding translation

    DEFF Research Database (Denmark)

    Schjoldager, Anne Gram; Gottlieb, Henrik; Klitgård, Ida

    Understanding Translation is designed as a textbook for courses on the theory and practice of translation in general and of particular types of translation - such as interpreting, screen translation and literary translation. The aim of the book is to help you gain an in-depth understanding...... of the phenomenon of translation and to provide you with a conceptual framework for the analysis of various aspects of professional translation. Intended readers are students of translation and languages, but the book will also be relevant for others who are interested in the theory and practice of translation...... - translators, language teachers, translation users and literary, TV and film critics, for instance. Discussions focus on translation between Danish and English....

  11. Understand electronics

    CERN Document Server

    Bishop, Owen

    2013-01-01

    Understand Electronics provides a readable introduction to the exciting world of electronics for the student or enthusiast with little previous knowledge. The subject is treated with the minimum of mathematics and the book is extensively illustrated.This is an essential guide for the newcomer to electronics, and replaces the author's best-selling Beginner's Guide to Electronics.The step-by-step approach makes this book ideal for introductory courses such as the Intermediate GNVQ.

  12. Understanding users

    DEFF Research Database (Denmark)

    Johannsen, Carl Gustav Viggo

    2014-01-01

    Segmentation of users can help libraries in the process of understanding user similarities and differences. Segmentation can also form the basis for selecting segments of target users and for developing tailored services for specific target segments. Several approaches and techniques have been...... segmentation project using computer-generated clusters. Compared to traditional marketing texts, this article also tries to identify user segments or images or metaphors by the library profession itself....

  13. Understanding unemployment

    OpenAIRE

    Guillaume Rocheteau

    2006-01-01

    Modern economists have built models of the labor market, which isolate the market’s key drivers and describe the way these interact to produce particular levels of unemployment. One of the most popular models used by macroeconomists today is the search-matching model of equilibrium unemployment. We explain this model, and show how it can be applied to understand the way various policies, such as unemployment benefits, taxes, or technological changes, can affect the unemployment rate.

  14. Understanding Technology?

    Directory of Open Access Journals (Sweden)

    Erik Bendtsen

    2016-11-01

    Full Text Available We are facing radical changes in our ways of living in the nearest future. Not necessarily of our own choice, but because tchnological development is moving so fast, that it will have still greater impact on many aspects of our lives. We have seen the beginnings of that change within the latest 35 years or so, but according to newest research that change will speed up immensely in the nearest years to come. The impact of that change or these changes will affect our working life immensely as a consequence of automation. How these changes are brought about and which are their consequences in a broad sense is being attempted to be understood and guessed by researchers. No one knows for sure, but specific patterns are visible. This paper will not try to guess, what will come, but will rather try to understand the deepest ”nature” of technology in order to understand the driving factors in this development: the genesis of technology in a broad sense in order to contibute to the understanding of the basis for the expected development.

  15. Understanding uncertainty

    CERN Document Server

    Lindley, Dennis V

    2013-01-01

    Praise for the First Edition ""...a reference for everyone who is interested in knowing and handling uncertainty.""-Journal of Applied Statistics The critically acclaimed First Edition of Understanding Uncertainty provided a study of uncertainty addressed to scholars in all fields, showing that uncertainty could be measured by probability, and that probability obeyed three basic rules that enabled uncertainty to be handled sensibly in everyday life. These ideas were extended to embrace the scientific method and to show how decisions, containing an uncertain element, could be rationally made.

  16. Understanding ayurveda.

    Science.gov (United States)

    Gadgil, Vaidya Dilip

    2010-01-01

    Ayurveda needs to achieve its full potential both in India and globally. This requires imparting to its students full appreciation of Ayurveda's power and strength, particularly proper understanding of the advantages of applying it to treat chronic and acute diseases. To this end, we explain the necessity of learning Sanskrit as a medium of study, and the advantages of learning the Texts in the traditional way, rather than relying on translations with all the loss of meaning and precision, which that entails. We emphasize the use of Triskandhakosha as a means to fully understand Ayurveda fundamental concepts and technical terms, so that all their shades of meaning are fully understood, and all their usages given in different places in the texts. Only by such methods can full appreciation of Ayurvedic wisdom be achieved, and the full depth and power of its knowledge be applied. Only then will its true status among systems of medicine come to be appreciated, either in India or more widely in the world as a whole.

  17. Understanding Ayurveda

    Directory of Open Access Journals (Sweden)

    Vaidya Dilip Gadgil

    2010-01-01

    Full Text Available Ayurveda needs to achieve its full potential both in India and globally. This requires imparting to its students full appreciation of Ayurveda′s power and strength, particularly proper understanding of the advantages of applying it to treat chronic and acute diseases. To this end, we explain the necessity of learning Sanskrit as a medium of study, and the advantages of learning the Texts in the traditional way, rather than relying on translations with all the loss of meaning and precision, which that entails. We emphasize the use of Triskandhakosha as a means to fully understand Ayurveda fundamental concepts and technical terms, so that all their shades of meaning are fully understood, and all their usages given in different places in the texts. Only by such methods can full appreciation of Ayurvedic wisdom be achieved, and the full depth and power of its knowledge be applied. Only then will its true status among systems of medicine come to be appreciated, either in India or more widely in the world as a whole.

  18. Exploring the Association between Cognitive Functioning and Anxiety in Children with Autism Spectrum Disorders: The Role of Social Understanding and Aggression

    Science.gov (United States)

    Niditch, Laura A.; Varela, R. Enrique; Kamps, Jodi L.; Hill, Trenesha

    2012-01-01

    This study examined relations between anxiety, aggression, social understanding, IQ, and diagnosis in a sample of 231 children (ages 2-9) diagnosed with Autism Spectrum Disorders (ASDs; Autistic Disorder, Asperger's Disorder, Pervasive Developmental Disorder Not Otherwise Specified) in a hospital setting. Children were administered tests of IQ,…

  19. Intracellular expression of Tat alters mitochondrial functions in T cells: a potential mechanism to understand mitochondrial damage during HIV-1 replication

    OpenAIRE

    Rodríguez-Mora, Sara; Mateos, Elena; Moran, María; Martín, Miguel Ángel; López, Juan Antonio; Calvo, Enrique; Terrón, María Carmen; Luque, Daniel; Muriaux, Delphine; Alcamí, José; Coiras, Mayte; López-Huertas, María Rosa

    2015-01-01

    Background HIV-1 replication results in mitochondrial damage that is enhanced during antiretroviral therapy (ART). The onset of HIV-1 replication is regulated by viral protein Tat, a 101-residue protein codified by two exons that elongates viral transcripts. Although the first exon of Tat (aa 1–72) forms itself an active protein, the presence of the second exon (aa 73–101) results in a more competent transcriptional protein with additional functions. Results Mitochondrial overall functions we...

  20. Understanding physics

    CERN Document Server

    Cassidy, David; Rutherford, James

    2002-01-01

    Understanding Physics provides a thorough grounding in contemporary physics while placing physics into its social and historical context Based in large part on the highly respected Project Physics Course developed by two of the authors, it also integrates the results of recent pedagogical research The text thus - teaches about the basic phenomena in the physical world and the concepts developed to explain them - shows that science is a rational human endeavor with a long and continuing tradition, involving many different cultures and people - develops facility in critical thinking, reasoned argumentation, evaluation of evidence, mathematical modeling, and ethical values The treatment emphasizes not only what we know but also how we know it, why we believe it, and what effects that knowledge has - Why do we believe the Earth and planets revolve around the Sun? - Why do we believe that matter is made of atoms? - How do relativity theory and quantum mechanics alter our conception of Nature and in what ways do th...

  1. Ergonomics and Beyond: Understanding How Chemical and Heat Exposures and Physical Exertions at Work Affect Functional Ability, Injury, and Long-Term Health.

    Science.gov (United States)

    Ross, Jennifer A; Shipp, Eva M; Trueblood, Amber B; Bhattacharya, Amit

    2016-08-01

    To honor Tom Waters's work on emerging occupational health issues, we review the literature on physical along with chemical exposures and their impact on functional outcomes. Many occupations present the opportunity for exposure to multiple hazardous exposures, including both physical and chemical factors. However, little is known about how these different factors affect functional ability and injury. The goal of this review is to examine the relationships between these exposures, impairment of the neuromuscular and musculoskeletal systems, functional outcomes, and health problems with a focus on acute injury. Literature was identified using online databases, including PubMed, Ovid Medline, and Google Scholar. References from included articles were searched for additional relevant articles. This review documented the limited existing literature that discussed cognitive impairment and functional disorders via neurotoxicity for physical exposures (heat and repetitive loading) and chemical exposures (pesticides, volatile organic compounds [VOCs], and heavy metals). This review supports that workers are exposed to physical and chemical exposures that are associated with negative health effects, including functional impairment and injury. Innovation in exposure assessment with respect to quantifying the joint exposure to these different exposures is especially needed for developing risk assessment models and, ultimately, preventive measures. Along with physical exposures, chemical exposures need to be considered, alone and in combination, in assessing functional ability and occupationally related injuries. © 2016, Human Factors and Ergonomics Society.

  2. Functional

    Directory of Open Access Journals (Sweden)

    Fedoua Gandia

    2014-07-01

    Full Text Available The study was carried out to investigate the effects of inhaled Mg alone and associated with F in the treatment of bronchial hyperresponsiveness. 43 male Wistar rats were randomly divided into four groups and exposed to inhaled NaCl 0.9%, MeCh, MgSO4 and MgF2. Pulmonary changes were assessed by means of functional tests and quantitative histological examination of lungs and trachea. Results revealed that delivery of inhaled Mg associated with F led to a significant decrease of total lung resistance better than inhaled Mg alone (p < 0.05. Histological examinations illustrated that inhaled Mg associated with F markedly suppressed muscular hypertrophy (p = 0.034 and bronchoconstriction (p = 0.006 in MeCh treated rats better than inhaled Mg alone. No histological changes were found in the trachea. This study showed that inhaled Mg associated with F attenuated the main principle of the central components of changes in MeCh provoked experimental asthma better than inhaled Mg alone, potentially providing a new therapeutic approach against asthma.

  3. Understanding the physics of functional fibers in the gastrointestinal tract: an evidence-based approach to resolving enduring misconceptions about insoluble and soluble fiber

    Science.gov (United States)

    Enduring misconceptions about the physical effects of fiber in the gut have led to misunderstandings about the health benefits attributable to insoluble and soluble fiber. This review will focus on isolated functional fibers (eg, fiber supplements) whose effects on clinical outcomes have been readil...

  4. Understanding PISA

    Directory of Open Access Journals (Sweden)

    Stephen DOWNES

    2005-04-01

    Full Text Available Understanding PISA Stephen DOWNESMoncton, CANADA ABSTRACT The headline was dramatic enough to cause a ripple in the reading public. "Students who use computers a lot at school have worse maths and reading performance," noted the BBC news article, citing a 2004 study by Ludger Woessmann and Thomas Fuchs (Fuchs and Woessman, 2004. It was not long before the blogosphere took notice. Taking the theme and running with it, Alice and Bill ask, "Computers Make School Kids Dumber?" They theorize, "If you track the admitted decline of education, you'll probably notice that it follows along with the increase of technology in the classroom." In a similar vein, James Bartholomew asks, "Do you think that the government will turn down the volume of its boasting about how it has spent billions introducing computers in schools (while keeping down the pay of teachers so much that there are shortages? Do you think it will stop sending governors of state schools glossy pamphlets about insisting that computers are used in their schools as much as possible?" In this study, therefore, PISA looks well beyond educational attainment, and also includes school demographics, such as whether it is a public or private school, has large or small classes, or has access or not to technological resources. Finally, it does measure student information-their family background, access to books and computers and parental support as well. The PISA survey departs from previous surveys in disregarding the stated curricula of the schools being measured. Therefore, the conclusion is not surprising, nor even wrong for him to consider independently of any parental or teacher support, considered without reference to the software running on it, considered without reference to student attitudes and interests, does not positively impact an education. Finally, he focus on missing the reporting of results

  5. Understanding marijuana's effects on functional connectivity of the default mode network in patients with schizophrenia and co-occurring cannabis use disorder: A pilot investigation.

    Science.gov (United States)

    Whitfield-Gabrieli, Susan; Fischer, Adina S; Henricks, Angela M; Khokhar, Jibran Y; Roth, Robert M; Brunette, Mary F; Green, Alan I

    2018-04-01

    Nearly half of patients with schizophrenia (SCZ) have co-occurring cannabis use disorder (CUD), which has been associated with decreased treatment efficacy, increased risk of psychotic relapse, and poor global functioning. While reports on the effects of cannabis on cognitive performance in patients with SCZ have been mixed, study of brain networks related to executive function may clarify the relationship between cannabis use and cognition in these dual-diagnosis patients. In the present pilot study, patients with SCZ and CUD (n=12) and healthy controls (n=12) completed two functional magnetic resonance imaging (fMRI) resting scans. Prior to the second scan, patients smoked a 3.6% tetrahydrocannabinol (THC) cannabis cigarette or ingested a 15mg delta-9-tetrahydrocannabinol (THC) pill. We used resting-state functional connectivity to examine the default mode network (DMN) during both scans, as connectivity/activity within this network is negatively correlated with connectivity of the network involved in executive control and shows reduced activity during task performance in normal individuals. At baseline, relative to controls, patients exhibited DMN hyperconnectivity that correlated with positive symptom severity, and reduced anticorrelation between the DMN and the executive control network (ECN). Cannabinoid administration reduced DMN hyperconnectivity and increased DMN-ECN anticorrelation. Moreover, the magnitude of anticorrelation in the controls, and in the patients after cannabinoid administration, positively correlated with WM performance. The finding that DMN brain connectivity is plastic may have implications for future pharmacotherapeutic development, as treatment efficacy could be assessed through the ability of therapies to normalize underlying circuit-level dysfunction. Copyright © 2017. Published by Elsevier B.V.

  6. First-year university Physics students’ knowledge about direct current circuits: probing improvement in understanding as a function of teaching and learning interventions

    Science.gov (United States)

    Newman, Richard; van der Ventel, Brandon; Hanekom, Crischelle

    2017-07-01

    Probing university students’ understanding of direct-current (DC) resistive circuits is still a field of active physics education research. We report here on a study we conducted of this understanding, where the cohort consisted of students in a large-enrollment first-year physics module. This is a non-calculus based physics module for students in the life sciences stream. The study involved 366 students enrolled in the physics (bio) 154 module at Stellenbosch University in 2015. Students’ understanding of DC resistive circuits was probed by means of a standardized test instrument. The instrument comprises 29 multiple choice questions that students have to answer in ~40 min. Students were required to first complete the standardized test at the start of semester (July 2015). For ease of reference we call this test the pre-test. Students answered the pre-test having no university-level formal exposure to DC circuits in theory or practice. The pre-test therefore served to probe students’ school level knowledge of DC circuits. As the semester progressed students were exposed to a practical (E1), lectures, a prescribed textbook, a tutorial and online videos focusing on DC circuits. The E1 practical required students to solve DC circuit problems by means of physically constructing circuits, algebraically using Kirchhoff's Rules and Ohm’s Law, and by means of simulating circuits using the app iCircuit running on iPads (iOS platform). Each E1 practical involved ~50 students in a three hour session. The practical was repeated three afternoons per week over an eight week period. Twenty three iPads were distributed among students on a practical afternoon in order for them to do the circuit simulations in groups (of 4-5 students). At the end of the practical students were again required to do the standardized test on circuits and complete a survey on their experience of the use of the iPad and iCircuit app. For ease of reference we refer to this second test as the

  7. Using the international classification of functioning, disability and health to expand understanding of paralysis in the United States through improved surveillance.

    Science.gov (United States)

    Fox, Michael H; Krahn, Gloria L; Sinclair, Lisa B; Cahill, Anthony

    2015-07-01

    Surveillance on paralysis prevalence has been conceptually and methodologically challenging. Numerous methods have been used to approximate population-level paralysis prevalence estimates leading to widely divergent prevalence estimates. To describe three phases in use of the International Classification of Functioning, Disability and Health (ICF) as a framework and planning tool for defining paralysis and developing public health surveillance of this condition. Description of the surveillance methodology covers four steps: an assessment of prior data collection efforts that included a review of existing surveys, registries and other data collection efforts designed to capture both case definitions in use and prevalence of paralysis; use of a consensus conference of experts to develop a case definition of paralysis based on the ICF rather than medical diagnostic criteria; explanation of use of the ICF framework for domains of interest to develop, cognitively test, validate and administer a brief self-report questionnaire for telephone administration on a population; and development and administration of a Paralysis Prevalence and Health Disparities Survey that used content mapping to back code items from existing national surveys to operationalize key domains. ICF coding led to a national population-based survey of paralysis that produced accurate estimates of prevalence and identification of factors related to the health of people in the U.S. living with paralysis. The ICF can be a useful tool for developing valid and reliable surveillance strategies targeting subgroups of individuals with functional disabilities such as people with paralysis and others. Published by Elsevier Inc.

  8. Toward understanding the insight paradox: internalized stigma moderates the association between insight and social functioning, hope, and self-esteem among people with schizophrenia spectrum disorders.

    Science.gov (United States)

    Lysaker, Paul H; Roe, David; Yanos, Philip T

    2007-01-01

    Research has paradoxically linked awareness of illness to both better function outcomes and lesser hope and self-esteem. One possible explanation for these findings is that acceptance of having schizophrenia may impact outcomes differently depending on the meanings the person attaches to this acceptance, particularly whether he or she accepts stigmatizing beliefs about mental illness. To explore this possibility we performed a cluster analysis of 75 persons with schizophrenia spectrum disorders based on single measures of insight using the Positive and Negative Syndrome Scale, internalized stigma using the Internalized Stigma of Mental Illness Scale, and compared groups on concurrent assessments of hope and self-esteem. Three groups were produced by the cluster analyses: low in sight/mild stigma (n = 23), high insight/minimal stigma (n = 25), and high insight/moderate stigma (n = 27). As predicted, analysis of variance-comparing groups revealed that the high insight/moderate stigma group had significantly the lowest levels of hope on the Beck Hopelessness Scale and self-esteem using the Multidimensional Self-esteem Inventory. As predicted, the high insight/minimal stigma group also had significantly less impaired social function than the other groups. Implications for assisting persons to come to cope with awareness of illness and stigma are discussed.

  9. Cognitive styles and psychological functioning in rural South African school students: Understanding influences for risk and resilience in the face of chronic adversity.

    Science.gov (United States)

    Cortina, Melissa A; Stein, Alan; Kahn, Kathleen; Hlungwani, Tintswalo Mercy; Holmes, Emily A; Fazel, Mina

    2016-06-01

    Adverse childhood experiences can show lasting effects on physical and mental health. Major questions surround how children overcome adverse circumstances to prevent negative outcomes. A key factor determining resilience is likely to be cognitive interpretation (how children interpret the world around them). The cognitive interpretations of 1025 school children aged 10-12 years in a rural, socioeconomically disadvantaged area of South Africa were examined using the Cognitive Triad Inventory for Children (CTI-C). These were examined in relation to psychological functioning and perceptions of the school environment. Those with more positive cognitive interpretations had better psychological functioning on scales of depression, anxiety, somatization and sequelae of potentially traumatic events. Children with more negative cognitions viewed the school-environment more negatively. Children living in poverty in rural South Africa experience considerable adversity and those with negative cognitions are at risk for psychological problems. Targeting children's cognitive interpretations may be a possible area for intervention. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  10. Understanding the sorption behavior of Pu{sup 4+} on poly(amidoamine) dendrimer functionalized carbon nanotube. Sorption equilibrium, mechanism, kinetics, radiolytic stability, and back-extraction studies

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Parveen [Indian Institute of Technology, Himachal Pradesh (India); Sengupta, Arijit [Bahbha Atomic Research Centre, Mumbai (India). Radiochemistry Div.; Deb, Ashish Kumar Singha; Ali, S. Musharaf [Bahbha Atomic Research Centre, Mumbai (India). Chemical Engineering Div.; Homi Bhabha National Institute, Mumbai (India); Dasgupta, Kinshuk [Bhabha National Institute, Mumbai (India). Mechanical Metallurgy Div.

    2017-07-01

    Poly(amidoamine) dendrimer functionalized carbon nanotube was demonstrated as highly efficient sorbent of the Pu{sup 4+} from radioactive waste solution. The second generation dendrimer was found to have more efficiency as compared to the 1{sup st} generation might be due to the availability of more functionality for coordinating to the Pu{sup 4+} ion. Analysis of different isotherm models revealed that, Langmuir isotherm was predominantly operating through chemi-sorption (with the sorption energy 10.07 and 16.95 kJ mol{sup -1} for 1{sup st} and 2{sup nd} generation dendrimer) with the sorption capacity 89.22 mg g{sup -1} and 92.48 mg g{sup -1} for 1{sup st} and 2{sup nd} generation dendrimer, respectively. Analysis of different sorption kinetics model revealed that the sorption proceeded via pseudo 2{sup nd} order reaction. The 2{sup nd} generation dendrimer was found to be radiolytically more stable while oxalic acid was found to be suitable for quantitative back extraction of Pu{sup 4+}.

  11. Thermodynamics of cooperative binding of FAD to human NQO1: Implications to understanding cofactor-dependent function and stability of the flavoproteome.

    Science.gov (United States)

    Clavería-Gimeno, Rafael; Velazquez-Campoy, Adrian; Pey, Angel Luis

    2017-12-15

    The stability of human flavoproteins strongly depends on flavin levels, although the structural and energetic basis of this relationship is poorly understood. Here, we report an in-depth analysis on the thermodynamics of FAD binding to one of the most representative examples of such relationship, NAD(P)H:quinone oxidoreductase 1 (NQO1). NQO1 is a dimeric enzyme that tightly binds FAD, which triggers large structural changes upon binding. A common cancer-associated polymorphism (P187S) severely compromises FAD binding. We show that FAD binding is described well by a thermodynamic model explicitly incorporating binding cooperativity when applied to different sets of calorimetric analyses and NQO1 variants, thus providing insight on the effects in vitro and in cells of cancer-associated P187S, its suppressor mutation H80R and the role of NQO1 C-terminal domain to modulate binding cooperativity and energetics. Furthermore, we show that FAD binding to NQO1 is very sensitive to physiologically relevant environmental conditions, such as the presence of phosphate buffer and salts. Overall, our results contribute to understanding at the molecular level the link between NQO1 stability and fluctuations of FAD levels intracellularly, and supports the notion that FAD binding energetics and cooperativity are fundamentally linked with the dynamic nature of apo-NQO1 conformational ensemble. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. 3D structure of macropore networks within natural and de-embarked estuary saltmarsh sediments: towards an improved understanding of network structural control over hydrologic function

    Science.gov (United States)

    Carr, Simon; Spencer, Kate; James, Tempest; Lucy, Diggens

    2015-04-01

    Saltmarshes are globally important environments which, though occupying pollution resulting in degradation. To compensate for this habitat loss many coastal restoration projects have been implemented over the last few decades, largely driven by legislative requirements for improved biodiversity e.g. the EU Habitats Directive and Birds Directive. However, there is growing evidence that restored saltmarshes, recreated through the return to tidal inundation of previously drained and defended low-lying coastal land, do not have the same species composition even after 100 years and while environmental enhancement has been achieved, there may be consequences for ecosystem functioning This study presents the findings of a comparative analysis of detailed sediment structure and hydrological functioning of equivalent natural and de-embanked saltmarsh sediments at Orplands Farm, Essex, UK. 3D x-ray CT scanning of triplicate undisturbed sediment cores recovered in 2013 have been used to derive detailed volumetric reconstructions of macropore structure and networks, and to infer differences in bulk microporosity between natural and de-embanked saltmarshes. These volumes have been further visualised for qualitative analysis of the main sediment components, and extraction of key macropore space parameters for quantified analysis including total porosity and connectivity, as well as structure, organisation and efficiency (tortuosity) of macropore networks. Although total porosity was significantly greater within the de-embanked saltmarsh sediments, pore networks in these samples were less organised and more tortuous, and were also inferred to have significantly lower micro-porosity than those of the natural saltmarsh. These datasets are applied to explain significant differences in the hydraulic behaviour and functioning observed between natural and de-embarked saltmarsh at Orplands. Piezometer wells and pressure transducers recorded fluctuations in water level at 15 minute

  13. Understanding the Effect of Ni on Mechanical and Wear Properties of Low-Carbon Steel from a View-Point of Electron Work Function

    Science.gov (United States)

    Lu, Hao; Huang, Xiaochen; Hou, Runfang; Li, D. Y.

    2018-04-01

    Electron work function (EWF) is correlated to intrinsic properties of metallic materials and can be an alternative parameter to obtain supplementary clues for guiding material design and modification. A higher EWF corresponds to a more stable electronic state, leading to higher resistance to any attempt to change the material structure and properties. In this study, effects of Ni as a solute with a higher EWF on mechanical, electrochemical, and tribological properties of low-carbon steel were investigated. Added Ni, which has more valence electrons, enhanced the electrons-nuclei interaction in the steel, corresponding to higher EWF. As a result, the Ni-added steel showed increased mechanical strength and corrosion resistance, resulting in higher resistances to wear and corrosive wear. Mechanism for the improvements is elucidated through analyzing EWF-related variations in Young's modulus, hardness, corrosion potential, and tribological behavior.

  14. Towards a molecular understanding of symbiont function: identification of a fungal gene for the degradation of xylan in the fungus gardens of leaf-cutting ants

    DEFF Research Database (Denmark)

    Schiøtt, Morten; De Fine Licht, Henrik H; Lange, Lene

    2008-01-01

    -substrate degradation in fungus gardens is a multi-step process comparable to normal biodegradation of organic matter in soil ecosystems, but with the crucial difference that a single fungal symbiont realizes most of the steps that are normally provided by a series of microorganisms that colonize fallen leaves...... in the fungus gardens in order to investigate the dynamics of degradation activities. RESULTS: We cloned a xylanase gene from the mutualistic fungus of Acromyrmex echinatior, determined its protein sequence, and inserted it in a yeast expression vector to confirm its substrate specificity. Our results show...... that the fungus has a functional xylanase gene. We also show by lab experiments in vivo that the activity of fungal xylanase and cellulase is not evenly distributed, but concentrated in the lower layer of fungus gardens, with only modest activity in the middle layer where gongylidia are produced and intermediate...

  15. Comparative modeling and molecular docking analysis of white, brown and soft rot fungal laccases using lignin model compounds for understanding the structural and functional properties of laccases.

    Science.gov (United States)

    Kameshwar, Ayyappa Kumar Sista; Barber, Richard; Qin, Wensheng

    2018-01-01

    Extrinsic catalytic properties of laccase enable it to oxidize a wide range of aromatic (phenolic and non-phenolic) compounds which makes it commercially an important enzyme. In this study, we have extensively compared and analyzed the physico-chemical, structural and functional properties of white, brown and soft rot fungal laccases using standard protein analysis software. We have computationally predicted the three-dimensional comparative models of these laccases and later performed the molecular docking studies using the lignin model compounds. We also report a customizable rapid and reliable protein modelling and docking pipeline for developing structurally and functionally stable protein structures. We have observed that soft rot fungal laccases exhibited comparatively higher structural variation (higher random coil) when compared to brown and white rot fungal laccases. White and brown rot fungal laccase sequences exhibited higher similarity for conserved domains of Trametes versicolor laccase, whereas soft rot fungal laccases shared higher similarity towards conserved domains of Melanocarpus albomyces laccase. Results obtained from molecular docking studies showed that aminoacids PRO, PHE, LEU, LYS and GLN were commonly found to interact with the ligands. We have also observed that white and brown rot fungal laccases showed similar docking patterns (topologically monomer, dimer and trimer bind at same pocket location and tetramer binds at another pocket location) when compared to soft rot fungal laccases. Finally, the binding efficiencies of white and brown rot fungal laccases with lignin model compounds were higher compared to the soft rot fungi. These findings can be further applied in developing genetically efficient laccases which can be applied in growing biofuel and bioremediation industries. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. The Use of Hydrograph Analysis and Impulse Response Functions to Improve Understanding of Groundwater Flooding: A Case Study from the Chalk Aquifer, United Kingdom.

    Science.gov (United States)

    Ascott, M.; Bloomfield, J.; Macdonald, D.; Marchant, B.; McKenzie, A.

    2017-12-01

    The Cretaceous Chalk, the most important aquifer in the United Kingdom (UK) for public water supply, underlies many large cities in southern and eastern England including parts of London, however, it is prone to groundwater flooding. We have developed a new approach to analyse the spatio-temporal extent of groundwater flooding using statistical analysis of groundwater level hydrographs and impulse response functions (IRFs) applied to a major Chalk groundwater flooding event in the UK during winter 2013/14. Using monthly groundwater levels for 26 boreholes in the Chalk and a new standardised index for groundwater flooding, we have: estimated standardised series; grouped them using k-means cluster analysis; and, cross-correlated the cluster centroids with the Standardised Precipitation Index accumulated over time intervals between 1 and 60 months. This analysis reveals two spatially coherent groups of standardised hydrographs which respond to precipitation over different timescales. We estimate IRF models of the groundwater level response to effective precipitation for three boreholes in each group. The IRF models support the SPI analysis showing different response functions between the two groups. If we apply identical effective precipitation inputs to each of the IRF models we see differences between the hydrographs from each group. It is proposed that these differences are due to the intrinsic, hydrogeological properties of the Chalk and of overlying relatively low permeability superficial deposits. Consequently, it is concluded that the overarching controls on groundwater flood response are a complex combination of antecedent conditions, rainfall and catchment hydrogeological properties. These controls should be taken into consideration when anticipating and managing future groundwater flood events.

  17. Application of Satellite Solar-Induced Chlorophyll Fluorescence to Understanding Large-Scale Variations in Vegetation Phenology and Function Over Northern High Latitude Forests

    Science.gov (United States)

    Jeong, Su-Jong; Schimel, David; Frankenberg, Christian; Drewry, Darren T.; Fisher, Joshua B.; Verma, Manish; Berry, Joseph A.; Lee, Jung-Eun; Joiner, Joanna

    2016-01-01

    This study evaluates the large-scale seasonal phenology and physiology of vegetation over northern high latitude forests (40 deg - 55 deg N) during spring and fall by using remote sensing of solar-induced chlorophyll fluorescence (SIF), normalized difference vegetation index (NDVI) and observation-based estimate of gross primary productivity (GPP) from 2009 to 2011. Based on GPP phenology estimation in GPP, the growing season determined by SIF time-series is shorter in length than the growing season length determined solely using NDVI. This is mainly due to the extended period of high NDVI values, as compared to SIF, by about 46 days (+/-11 days), indicating a large-scale seasonal decoupling of physiological activity and changes in greenness in the fall. In addition to phenological timing, mean seasonal NDVI and SIF have different responses to temperature changes throughout the growing season. We observed that both NDVI and SIF linearly increased with temperature increases throughout the spring. However, in the fall, although NDVI linearly responded to temperature increases, SIF and GPP did not linearly increase with temperature increases, implying a seasonal hysteresis of SIF and GPP in response to temperature changes across boreal ecosystems throughout their growing season. Seasonal hysteresis of vegetation at large-scales is consistent with the known phenomena that light limits boreal forest ecosystem productivity in the fall. Our results suggest that continuing measurements from satellite remote sensing of both SIF and NDVI can help to understand the differences between, and information carried by, seasonal variations vegetation structure and greenness and physiology at large-scales across the critical boreal regions.

  18. Sphagnum physiology in the context of changing climate: emergent influences of genomics, modelling and host-microbiome interactions on understanding ecosystem function.

    Science.gov (United States)

    Weston, David J; Timm, Collin M; Walker, Anthony P; Gu, Lianhong; Muchero, Wellington; Schmutz, Jeremy; Shaw, A Jonathan; Tuskan, Gerald A; Warren, Jeffrey M; Wullschleger, Stan D

    2015-09-01

    Peatlands harbour more than one-third of terrestrial carbon leading to the argument that the bryophytes, as major components of peatland ecosystems, store more organic carbon in soils than any other collective plant taxa. Plants of the genus Sphagnum are important components of peatland ecosystems and are potentially vulnerable to changing climatic conditions. However, the response of Sphagnum to rising temperatures, elevated CO2 and shifts in local hydrology have yet to be fully characterized. In this review, we examine Sphagnum biology and ecology and explore the role of this group of keystone species and its associated microbiome in carbon and nitrogen cycling using literature review and model simulations. Several issues are highlighted including the consequences of a variable environment on plant-microbiome interactions, uncertainty associated with CO2 diffusion resistances and the relationship between fixed N and that partitioned to the photosynthetic apparatus. We note that the Sphagnum fallax genome is currently being sequenced and outline potential applications of population-level genomics and corresponding plant photosynthesis and microbial metabolic modelling techniques. We highlight Sphagnum as a model organism to explore ecosystem response to a changing climate and to define the role that Sphagnum can play at the intersection of physiology, genetics and functional genomics. © 2014 The Authors. Plant, Cell & Environment published by John Wiley & Sons Ltd.

  19. A methodological approach to understand functional relationships between ecological indices and human-induced pressures: the case of the Posidonia oceanica meadows.

    Science.gov (United States)

    Bacci, Tiziano; Rende, Sante Francesco; Penna, Marina; Trabucco, Benedetta; Montefalcone, Monica; Cicero, Anna Maria; Giovanardi, Franco

    2013-11-15

    The European Water Framework Directive (WFD) 2000/60/EC requests the achievement of the Good Status for all surface waters, including the coastal waters, by 2015. In order to check compliance with the needs of Directive, Italian national monitoring data on Posidonia oceanica meadows have been explored and the relationships among the Posidonia Rapid and Easy Index (PREI), and human-induced pressures have been analyzed along the Italian coasts. The aim of this work is to establish functional relationships between a response variable (i.e. the PREI) and a set of potential pressure (i.e. land use, potential organic and nutrient loading, pesticides) and status (i.e. transparency, trophic level and stability of the water column) indicators in a quantitative way. The ecological responses of coastal marine environment have been evaluated using appropriate statistical tools, such as the multiple linear regression analyses and "linear programming" techniques. Results show that more than 70% of the variability of the P. oceanica meadows status, expressed as PREI value, is significantly explained only by a few pressure/status indicators (namely: potential organic load, specific nitrogen load, natural areas extent, water column transparency), among all those initially considered in the model. The application of the proposed model could allow decision makers to better address remedial actions and to achieve the environmental targets proposed by the EU Directives. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Connecting the Mind–Body Split: Understanding the Relationship between Symptoms and Emotional Well-Being in Chronic Pain and Functional Gastrointestinal Disorders

    Directory of Open Access Journals (Sweden)

    Line Caes

    2017-12-01

    Full Text Available Paediatric chronic conditions, e.g., chronic pain and functional gastrointestinal disorders, are commonly diagnosed, with fatigue, pain and abdominal discomfort the most frequently reported symptoms across conditions. Regardless of whether symptoms are connected to an underlying medical diagnosis or not, they are often associated with an increased experience of psychological distress by both the ill child and their parents. While pain and embarrassing symptoms can induce increased distress, evidence is also accumulating in support of a reciprocal relationship between pain and distress. This reciprocal relationship is nicely illustrated in the fear avoidance model of pain, which has recently been found to be applicable to childhood pain experiences. The purpose of this article is to illustrate how mind (i.e., emotions and body (i.e., physical symptoms interact using chronic pain and gastrointestinal disorders as key examples. Despite the evidence for the connection between mind and body, the mind–body split is still a dominant position for families and health care systems, as evidenced by the artificial split between physical and mental health care. In a mission to overcome this gap, this article will conclude by providing tools on how the highlighted evidence can help to close this gap between mind and body.

  1. The use of wavelength-selective plastic cladding materials in horticulture: understanding of crop and fungal responses through the assessment of biological spectral weighting functions.

    Science.gov (United States)

    Paul, Nigel D; Jacobson, Rob J; Taylor, Anna; Wargent, Jason J; Moore, Jason P

    2005-01-01

    Plant responses to light spectral quality can be exploited to deliver a range of agronomically desirable end points in protected crops. This can be achieved using plastics with specific spectral properties as crop covers. We have studied the responses of a range of crops to plastics that have either (a) increased transmission of UV compared with standard horticultural covers, (b) decreased transmission of UV or (c) increased the ratio of red (R) : far-red (FR) radiation. Both the UV-transparent and R : FR increasing films reduced leaf area and biomass, offering potential alternatives to chemical growth regulators. The UV-opaque film increased growth, but while this may be useful in some crops, there were trade-offs with elements of quality, such as pigmentation and taste. UV manipulation may also influence disease control. Increasing UV inhibited not only the pathogenic fungus Botrytis cinerea but also the disease biocontrol agent Trichoderma harzianum. Unlike B. cinerea, T. harzianum was highly sensitive to UV-A radiation. These fungal responses and those for plant growth in the growth room and the field under different plastics are analyzed in terms of alternative biological spectral weighting functions (BSWF). The role of BSWF in assessing general patterns of response to UV modification in horticulture is also discussed.

  2. A density functional reactivity theory (DFRT) based approach to understand the effect of symmetry of fullerenes on the kinetic, thermodynamic and structural aspects of carbon NanoBuds

    International Nuclear Information System (INIS)

    Sarmah, Amrit; Roy, Ram Kinkar

    2016-01-01

    Highlights: • Kinetic and thermodynamic aspects of the interaction between fullerene (C 32 ) and SWCNT using CDASE scheme. • Role of symmetry of fullerenes as well as the site of covalent attachment to the SWCNT in the structural stability of the NanoBud structure. • Increase in the fullerene symmetry improves the relative stability of hybrid NanoBud structure. - Abstract: In the present study, we have rationalized the effect of variation in the symmetry of relatively smaller fullerene (C 32 ) on the mode of its interaction with semi-conducting Single-Walled Carbon Nanotubes (SWCNTs) in the process of formation of stable hybrid carbon NanoBuds. Thermodynamic and kinetic parameters, along with the charge transfer values associated with the interaction between fullerene and SWCNTs, have been evaluated using an un-conventional and computationally cost–effective method based on density functional reactivity theory (DFRT). In addition to this, conventional DFT based studies are also performed to substantiate the growth of NanoBud structures formed by the interaction between fullerene and SWCNTs. The findings of the present study suggest that the kinetic, thermodynamic and structural aspects of hybrid carbon NanoBuds are significantly influenced by both the symmetry of C 32 fullerene and its site of covalent attachment to the SWCNT.

  3. Understanding and optimizing the dual excipient functionality of sodium lauryl sulfate in tablet formulation of poorly water soluble drug: wetting and lubrication.

    Science.gov (United States)

    Aljaberi, Ahmad; Chatterji, Ashish; Dong, Zedong; Shah, Navnit H; Malick, Waseem; Singhal, Dharmendra; Sandhu, Harpreet K

    2013-01-01

    To evaluate and optimize sodium lauryl sulfate (SLS) and magnesium stearate (Mg.St) levels, with respect to dissolution and compaction, in a high dose, poorly soluble drug tablet formulation. A model poorly soluble drug was formulated using high shear aqueous granulation. A D-optimal design was used to evaluate and model the effect of granulation conditions, size of milling screen, SLS and Mg.St levels on tablet compaction and ejection. The compaction profiles were generated using a Presster(©) compaction simulator. Dissolution of the kernels was performed using a USP dissolution apparatus II and intrinsic dissolution was determined using a stationary disk system. Unlike kernels dissolution which failed to discriminate between tablets prepared with various SLS contents, the intrinsic dissolution rate showed that a SLS level of 0.57% was sufficient to achieve the required release profile while having minimal effect on compaction. The formulation factors that affect tablet compaction and ejection were identified and satisfactorily modeled. The design space of best factor setting to achieve optimal compaction and ejection properties was successfully constructed by RSM analysis. A systematic study design helped identify the critical factors and provided means to optimize the functionality of key excipient to design robust drug product.

  4. Improved Understanding of Microbial Iron and Sulfate Reduction Through a Combination of Bottom-up and Top-down Functional Proteomics Assays

    Energy Technology Data Exchange (ETDEWEB)

    Richardson, Ruth [Cornell Univ., Ithaca, NY (United States)

    2016-02-28

    Our overall goal was to improve the understanding of microbial iron and sulfate reduction by evaluating a diverse iron and sulfate reducing organisms utilizing a multi-omics approach combining “top-down” and “bottom-up” omics methodologies. We initiated one of the first combined comparative genomics, shotgun proteomics, RTqPCR, and heterologous expression studies in pursuit of our project objectives. Within the first year of this project, we created a new bioinformatics tool for ortholog identification (“SPOCS”). SPOCS is described in our publication, Curtis et al., 2013. Using this tool we were able to identify conserved orthologous groups across diverse iron and sulfate reducing microorganisms from Firmicutes, gamma-proteobacteria and delta-proteobacteria. For six iron and sulfate reducers we also performed shotgun proteomics (“bottom-up” proteomics including accurate mass and time (AMT) tag and iTRAQ approaches). Cultures include Gram (-) and Gram (+) microbes. Gram (-) were: Geobacter sulfureducens (grown on iron citrate and fumarate), Geobacter bemidjiensis (grown on iron citrate and fumarate), Shewanella oneidiensis (grown on iron citrate and fumarate) and Anaeromyxobacter dehalogenans (grown on iron citrate and fumarate). Although all cultures grew on insoluble iron, the iron precipitates interfered with protein extraction and analysis; which remains a major challenge for researchers in disparate study systems. Among the Gram (-) organisms studied, Anaeromyxobacter dehalogenans remains the most poorly characterized. Yet, it is arguably the most versatile organisms we studied. In this work we have used comparative proteomics to hypothesize which two of the dozens of predicted c-type cytochromes within Anaeromyxobacter dehalogenans may be directly involved in soluble iron reduction. Unfortunately, heterologous expression of these Anaeromyxobacter dehalogenans ctype cytochromes led to poor protein production and/or formation of inclusion bodies

  5. Towards a comprehensive understanding of the chemical vapor deposition of titanium nitride using Ti(NMe2)4: a density functional theory approach.

    Science.gov (United States)

    Sen, Kaushik; Banu, Tahamida; Debnath, Tanay; Ghosh, Deepanwita; Das, Abhijit K

    2014-06-21

    A gas phase mechanistic investigation of the chemical vapor deposition (CVD) of titanium nitride (TiN) from the decomposition of Ti(NMe2)4, tetrakis(dimethylamido)titanium (TDMAT) as a single source precursor as well as from the reaction of Ti(NMe2)4 with NH3, i.e., the ammonia assisted mechanism is carried out and reported herein within the framework of density functional theory. Contrary to the theoretical result reported previously for a model TDMAT, metallacycle formation and β-H elimination pathways are found to be the major decomposition pathways responsible for the decomposition of TDMAT, and this finding is in accord with the experimental observation. Interestingly, agostic interaction is found to play a key role in promoting β-H elimination in the decomposition of TDMAT. A new additional pathway of decomposition of TDMAT has been identified theoretically in this present study. Exploration of the complex gas phase mechanism and thereby a detailed identification of the reaction intermediates enable us in realizing the origin of incorporation of carbon contamination in TiN films produced from TDMAT alone and then how the contamination is removed in the presence of ammonia. The ammonia assisted mechanism is found to proceed through the formation of a pre-equilibrium complex. The computed barrier height of 7.3 kcal mol(-1) for the initial transamination process associated with the Ti(NMe2)4 + NH3 reaction is found to be in very good agreement with the experimental activation energy. The total rate constant ktot for the ammonia assisted mechanism is calculated to be 1.28 × 10(-51) cm(3) molecule(-1) s(-1) at 298.15 K.

  6. Understanding the Thermal Stability of Palladium-Platinum Core-Shell Nanocrystals by In Situ Transmission Electron Microscopy and Density Functional Theory.

    Science.gov (United States)

    Vara, Madeline; Roling, Luke T; Wang, Xue; Elnabawy, Ahmed O; Hood, Zachary D; Chi, Miaofang; Mavrikakis, Manos; Xia, Younan

    2017-05-23

    Core-shell nanocrystals offer many advantages for heterogeneous catalysis, including precise control over both the surface structure and composition, as well as reduction in loading for rare and costly metals. Although many catalytic processes are operated at elevated temperatures, the adverse impacts of heating on the shape and structure of core-shell nanocrystals are yet to be understood. In this work, we used ex situ heating experiments to demonstrate that Pd@Pt 4L core-shell nanoscale cubes and octahedra are promising for catalytic applications at temperatures up to 400 °C. We also used in situ transmission electron microscopy to monitor the thermal stability of the core-shell nanocrystals in real time. Our results demonstrate a facet dependence for the thermal stability in terms of shape and composition. Specifically, the cubes enclosed by {100} facets readily deform shape at a temperature 300 °C lower than that of the octahedral counterparts enclosed by {111} facets. A reversed trend is observed for composition, as alloying between the Pd core and the Pt shell of an octahedron occurs at a temperature 200 °C lower than that for the cubic counterpart. Density functional theory calculations provide atomic-level explanations for the experimentally observed behaviors, demonstrating that the barriers for edge reconstruction determine the relative ease of shape deformation for cubes compared to octahedra. The opposite trend for alloying of the core-shell structure can be attributed to a higher propensity for subsurface Pt vacancy formation in octahedra than in cubes.

  7. Understanding the Physics of Functional Fibers in the Gastrointestinal Tract: An Evidence-Based Approach to Resolving Enduring Misconceptions about Insoluble and Soluble Fiber.

    Science.gov (United States)

    McRorie, Johnson W; McKeown, Nicola M

    2017-02-01

    Enduring misconceptions about the physical effects of fiber in the gut have led to misunderstandings about the health benefits attributable to insoluble and soluble fiber. This review will focus on isolated functional fibers (eg, fiber supplements) whose effects on clinical outcomes have been readily assessed in well-controlled clinical studies. This review will also focus on three health benefits (cholesterol lowering, improved glycemic control, and normalizing stool form [constipation and diarrhea]) for which reproducible evidence of clinical efficacy has been published. In the small bowel, clinically meaningful health benefits (eg, cholesterol lowering and improved glycemic control) are highly correlated with the viscosity of soluble fibers: high viscosity fibers (eg, gel-forming fibers such as b-glucan, psyllium, and raw guar gum) exhibit a significant effect on cholesterol lowering and improved glycemic control, whereas nonviscous soluble fibers (eg, inulin, fructooligosaccharides, and wheat dextrin) and insoluble fibers (eg, wheat bran) do not provide these viscosity-dependent health benefits. In the large bowel, there are only two mechanisms that drive a laxative effect: large/coarse insoluble fiber particles (eg, wheat bran) mechanically irritate the gut mucosa stimulating water and mucous secretion, and the high water-holding capacity of gel-forming soluble fiber (eg, psyllium) resists dehydration. Both mechanisms require that the fiber resist fermentation and remain relatively intact throughout the large bowel (ie, the fiber must be present in stool), and both mechanisms lead to increased stool water content, resulting in bulky/soft/easy-to-pass stools. Soluble fermentable fibers (eg, inulin, fructooligosaccharide, and wheat dextrin) do not provide a laxative effect, and some fibers can be constipating (eg, wheat dextrin and fine/smooth insoluble wheat bran particles). When making recommendations for a fiber supplement, it is essential to recognize which

  8. Understanding text as social practice: An exploration of the potential of systemic functional grammar to facilitate students' interpretation of media texts.

    Directory of Open Access Journals (Sweden)

    Jenny Clarence-Fincham

    2008-08-01

    Full Text Available It has frequently been claimed that Halliday's Systemic Functional Grammar (SFG is apowerful linguistic tool which facilitates analytical and interpretative skills and provides aflexible, yet structured set of analytical tools with which to interpret texts. With this claim asa backdrop, this article asks whether SFG is, in fact an appropriate analytical approach forunder-graduate students and whether it can facilitate their ability to analyse texts. Its contextis a second level course, Analysing Media Texts, offered at Natal University. Broadly framedby critical discourse analysis, it traces the development of a thirteen week module and,using student analyses for illustrative purposes, identifies pedagogical challenges anddifficulties that need to be confronted before any strong claims can be made. It is concludedthat, on the evidence of students' responses to texts analysed during this course, it is not yetpossible to make strong claims about the benefits of SFG. There is enough positiveevidence, however, to pursue the possibility that with innovative curriculum development andthe careful scaffolding and integration of concepts, SFG will be clearly shown to have anextremely important role to play.Daar is dikwels beweer dat Halliday se Sistemies-Funksionele Grammatika (SFG 'n kragtige linguistiese middel is wat analitiese en interpreterende vaardighede bevorder en 'n plooibare, dog gestruktureere stel analitiese gereedskap verskaf waarmee tekste gei"nterpreteer kan word. Met die bewering as agtergrond vra hierdie artikel of SFG inderdaad 'n toepas like analitiese benadering vir voorgraadse studente is en of dit hulle vermoe om tekste te ontleed, bevorder. Die konteks is 'n tweedejaarskursus, Analysing Media Texts, wat aan die Universiteit van Natal aangebied word. Breedweg omraam deur kritiese diskoersanalise, speur die artikel die ontwikkeling van 'n module van dertien weke na, met gebruik van studenteontledings ter illustrasie en identifiseer

  9. Understanding the life of a sandy beach polychaete of functional importance - Scolelepis squamata (Polychaeta: Spionidae) on Belgian sandy beaches (northeastern Atlantic, North Sea)

    Science.gov (United States)

    Speybroeck, Jeroen; Alsteens, Lotte; Vincx, Magda; Degraer, Steven

    2007-08-01

    The cosmopolitan sandy beach polychaete Scolelepis squamata constitutes an important food resource for juvenile flatfish and wading birds in the northeastern Atlantic, thus playing an important role in sandy beach ecosystem functioning. However, its population dynamics and life history in this part of the world have gone widely uninvestigated. Eight beach transects on Belgian sandy beaches were sampled monthly from October 2003 until October 2004, in order to investigate seasonal trends in the species' abundance, biomass, secondary production, and patterns in reproduction and zonation. Average density, modal density and modal biomass (ash-free dry weight) (mean average density = 169 ± 9 SE ind/m 2; mean modal density = 505 ± 38 SE ind/m 2; mean modal biomass = 0.25 ± 0.02 SE g/m 2) did not exhibit major seasonal changes, whereas average biomass (0.081 ± 0.005 SE g/m 2) and individuals and biomass per strip transect (IST = 16286 ± 1330 SE ind/m; BMST = 7.8 + 0.7 SE g/m) did, peaking in May 2004. Production was calculated at 1.9 g/(m 2*year) (size-frequency method, SFM) and 0.88 g/(m 2*year) (mass specific growth rate method, MSGR) and mean annual biomass was 0.797 g/m 2; resulting in a P/B ratio of 2.40/year (SFM) and 1.11/year (MSGR), which is intermediate to moderately low compared to other polychaete species. Gravid individuals were found from February until August and a single recruitment period was observed from July until September. An average sex ratio of 1.41 ± 0.08 SE was calculated, with a female predominance. Highest densities (>200 ind/m 2) were mostly found above 3 m above MLLWS and at a median grain size from 190 to 320 μm. Average modal or peak density along each transect was situated from 3.95 m up to 4.40 m above MLLWS, in contrast to some other studies where the species was restricted to mid-tidal levels. Significant differences in elevation of peak density were found between non-gravid (411 ± 4 SE cm) and gravid (402 ± 5 SE cm) animals

  10. Intention understanding in autism.

    Directory of Open Access Journals (Sweden)

    Sonia Boria

    Full Text Available When we observe a motor act (e.g. grasping a cup done by another individual, we extract, according to how the motor act is performed and its context, two types of information: the goal (grasping and the intention underlying it (e.g. grasping for drinking. Here we examined whether children with autistic spectrum disorder (ASD are able to understand these two aspects of motor acts. Two experiments were carried out. In the first, one group of high-functioning children with ASD and one of typically developing (TD children were presented with pictures showing hand-object interactions and asked what the individual was doing and why. In half of the "why" trials the observed grip was congruent with the function of the object ("why-use" trials, in the other half it corresponded to the grip typically used to move that object ("why-place" trials. The results showed that children with ASD have no difficulties in reporting the goals of individual motor acts. In contrast they made several errors in the why task with all errors occurring in the "why-place" trials. In the second experiment the same two groups of children saw pictures showing a hand-grip congruent with the object use, but within a context suggesting either the use of the object or its placement into a container. Here children with ASD performed as TD children, correctly indicating the agent's intention. In conclusion, our data show that understanding others' intentions can occur in two ways: by relying on motor information derived from the hand-object interaction, and by using functional information derived from the object's standard use. Children with ASD have no deficit in the second type of understanding, while they have difficulties in understanding others' intentions when they have to rely exclusively on motor cues.

  11. Integrating landscape system and meta-ecosystem frameworks to advance the understanding of ecosystem function in heterogeneous landscapes: An analysis on the carbon fluxes in the Northern Highlands Lake District (NHLD) of Wisconsin and Michigan

    Science.gov (United States)

    Chen, Jiakuan

    2018-01-01

    The successful integration of ecosystem ecology with landscape ecology would be conducive to understanding how landscapes function. There have been several attempts at this, with two main approaches: (1) an ecosystem-based approach, such as the meta-ecosystem framework and (2) a landscape-based approach, such as the landscape system framework. These two frameworks are currently disconnected. To integrate these two frameworks, we introduce a protocol, and then demonstrate application of the protocol using a case study. The protocol includes four steps: 1) delineating landscape systems; 2) classifying landscape systems; 3) adjusting landscape systems to meta-ecosystems and 4) integrating landscape system and meta-ecosystem frameworks through meta-ecosystems. The case study is the analyzing of the carbon fluxes in the Northern Highlands Lake District (NHLD) of Wisconsin and Michigan using this protocol. The application of this protocol revealed that one could follow this protocol to construct a meta-ecosystem and analyze it using the integrative framework of landscape system and meta-ecosystem frameworks. That is, one could (1) appropriately describe and analyze the spatial heterogeneity of the meta-ecosystem; (2) understand the emergent properties arising from spatial coupling of local ecosystems in the meta-ecosystem. In conclusion, this protocol is a useful approach for integrating the meta-ecosystem framework and the landscape system framework, which advances the describing and analyzing of the spatial heterogeneity and ecosystem function of interconnected ecosystems. PMID:29415066

  12. Integrating landscape system and meta-ecosystem frameworks to advance the understanding of ecosystem function in heterogeneous landscapes: An analysis on the carbon fluxes in the Northern Highlands Lake District (NHLD) of Wisconsin and Michigan.

    Science.gov (United States)

    Yang, Haile; Chen, Jiakuan

    2018-01-01

    The successful integration of ecosystem ecology with landscape ecology would be conducive to understanding how landscapes function. There have been several attempts at this, with two main approaches: (1) an ecosystem-based approach, such as the meta-ecosystem framework and (2) a landscape-based approach, such as the landscape system framework. These two frameworks are currently disconnected. To integrate these two frameworks, we introduce a protocol, and then demonstrate application of the protocol using a case study. The protocol includes four steps: 1) delineating landscape systems; 2) classifying landscape systems; 3) adjusting landscape systems to meta-ecosystems and 4) integrating landscape system and meta-ecosystem frameworks through meta-ecosystems. The case study is the analyzing of the carbon fluxes in the Northern Highlands Lake District (NHLD) of Wisconsin and Michigan using this protocol. The application of this protocol revealed that one could follow this protocol to construct a meta-ecosystem and analyze it using the integrative framework of landscape system and meta-ecosystem frameworks. That is, one could (1) appropriately describe and analyze the spatial heterogeneity of the meta-ecosystem; (2) understand the emergent properties arising from spatial coupling of local ecosystems in the meta-ecosystem. In conclusion, this protocol is a useful approach for integrating the meta-ecosystem framework and the landscape system framework, which advances the describing and analyzing of the spatial heterogeneity and ecosystem function of interconnected ecosystems.

  13. Understanding CrRLK1L Function

    DEFF Research Database (Denmark)

    Nissen, Karen Stoltenberg; Willats, William George Tycho; Malinovsky, Frederikke Gro

    2016-01-01

    To develop successfully in an ever-changing environment, it is essential for plants to monitor and control their growth. Therefore, cell expansion is carefully regulated to establish correct cell shape and size. In this review, we explore the role of the Catharanthus roseus receptor-like kinase (Cr......RLK1L) subfamily as regulators of cell expansion. Recently, the downstream signalling events of individual CrRLK1L pathways were discovered, implicating known modulators of cell expansion, such as reactive oxygen species (ROS) production, Ca(2+) dynamics, and exocytosis of cell wall material. Based...... on these intriguing new insights, we propose a model for a common pathway of CrRLK1L signalling that enables spatial and temporal control of cell wall extensibility throughout the plant....

  14. Understanding gene functions and disease mechanisms

    DEFF Research Database (Denmark)

    Fuchs, Helmut; Aguilar-Pimentel, Juan Antonio; Amarie, Oana V.

    2018-01-01

    . For hypothesis-driven phenotypic analyses, there are thirteen additional pipelines with focus on neurological and behavioral disorders, metabolic dysfunction, respiratory system malfunctions, immune-system disorders and imaging techniques. In this article, we give an overview of the pipelines and describe...

  15. Shape understanding system machine understanding and human understanding

    CERN Document Server

    Les, Zbigniew

    2015-01-01

    This is the third book presenting selected results of research on the further development of the shape understanding system (SUS) carried out by authors in the newly founded Queen Jadwiga Research Institute of Understanding. In this book the new term Machine Understanding is introduced referring to a new area of research aiming to investigate the possibility of building machines with the ability to understand. It is presented that SUS needs to some extent mimic human understanding and for this reason machines are evaluated according to the rules applied for the evaluation of human understanding. The book shows how to formulate problems and how it can be tested if the machine is able to solve these problems.    

  16. Kinking and Torsion Can Significantly Improve the Efficiency of Valveless Pumping in Periodically Compressed Tubular Conduits. Implications for Understanding of the Form-Function Relationship of Embryonic Heart Tubes

    Science.gov (United States)

    Hiermeier, Florian; Männer, Jörg

    2017-01-01

    Valveless pumping phenomena (peristalsis, Liebau-effect) can generate unidirectional fluid flow in periodically compressed tubular conduits. Early embryonic hearts are tubular conduits acting as valveless pumps. It is unclear whether such hearts work as peristaltic or Liebau-effect pumps. During the initial phase of its pumping activity, the originally straight embryonic heart is subjected to deforming forces that produce bending, twisting, kinking, and coiling. This deformation process is called cardiac looping. Its function is traditionally seen as generating a configuration needed for establishment of correct alignments of pulmonary and systemic flow pathways in the mature heart of lung-breathing vertebrates. This idea conflicts with the fact that cardiac looping occurs in all vertebrates, including gill-breathing fishes. We speculate that looping morphogenesis may improve the efficiency of valveless pumping. To test the physical plausibility of this hypothesis, we analyzed the pumping performance of a Liebau-effect pump in straight and looped (kinked) configurations. Compared to the straight configuration, the looped configuration significantly improved the pumping performance of our pump. This shows that looping can improve the efficiency of valveless pumping driven by the Liebau-effect. Further studies are needed to clarify whether this finding may have implications for understanding of the form-function relationship of embryonic hearts. PMID:29367548

  17. Kinking and Torsion Can Significantly Improve the Efficiency of Valveless Pumping in Periodically Compressed Tubular Conduits. Implications for Understanding of the Form-Function Relationship of Embryonic Heart Tubes

    Directory of Open Access Journals (Sweden)

    Florian Hiermeier

    2017-11-01

    Full Text Available Valveless pumping phenomena (peristalsis, Liebau-effect can generate unidirectional fluid flow in periodically compressed tubular conduits. Early embryonic hearts are tubular conduits acting as valveless pumps. It is unclear whether such hearts work as peristaltic or Liebau-effect pumps. During the initial phase of its pumping activity, the originally straight embryonic heart is subjected to deforming forces that produce bending, twisting, kinking, and coiling. This deformation process is called cardiac looping. Its function is traditionally seen as generating a configuration needed for establishment of correct alignments of pulmonary and systemic flow pathways in the mature heart of lung-breathing vertebrates. This idea conflicts with the fact that cardiac looping occurs in all vertebrates, including gill-breathing fishes. We speculate that looping morphogenesis may improve the efficiency of valveless pumping. To test the physical plausibility of this hypothesis, we analyzed the pumping performance of a Liebau-effect pump in straight and looped (kinked configurations. Compared to the straight configuration, the looped configuration significantly improved the pumping performance of our pump. This shows that looping can improve the efficiency of valveless pumping driven by the Liebau-effect. Further studies are needed to clarify whether this finding may have implications for understanding of the form-function relationship of embryonic hearts.

  18. Understanding Defense Mechanisms.

    Science.gov (United States)

    Cramer, Phebe

    2015-12-01

    Understanding defense mechanisms is an important part of psychotherapy. In this article, we trace the history of the concept of defense, from its origin with Freud to current views. The issue of defense as an unconscious mechanism is examined. The question of whether defenses are pathological, as well as their relation to pathology, is discussed. The effect of psychotherapy on the use of defenses, and their relation to a therapeutic alliance is explored. A series of empirical research studies that demonstrate the functioning of defense mechanisms and that support the theory is presented. Research also shows that as part of normal development, different defenses emerge at different developmental periods, and that gender differences in defense use occur.

  19. Understanding medical device regulation.

    Science.gov (United States)

    Galgon, Richard E

    2016-12-01

    The purpose of this article is to provide a structural and functional understanding of the systems used for the regulation of medical devices in the USA and European Union (EU). Safe and effective anesthesia care depends heavily on medical devices, including simple, low risk devices to complex life-supporting and life-sustaining devices. In the USA and EU, the Food and Drug Administration and European Commission, respectively, provide regulatory oversight to ensure medical devices are reasonably safe and effective when used for their intended purposes. Unfortunately, practicing anesthesiologists generally have little or no understanding of how medical devices are regulated, nor do they have sufficient knowledge of available adverse event reporting systems. The US and EU medical device regulatory systems are similar in many ways, but differ in important ways too, which impacts the afforded level of safety and effectiveness assurance. In both systems, medical devices are classified and regulated on a risk basis, which fundamentally differs from drug regulation, where uniform requirements are imposed. Anesthesia providers must gain knowledge of these systems and be active players in both premarket and postmarket activities, particularly with regard to vigilance and adverse event/device failure reporting.

  20. Understanding Lustre Internals

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Feiyi [ORNL; Oral, H Sarp [ORNL; Shipman, Galen M [ORNL; Drokin, Oleg [ORNL; Wang, Di [ORNL; Huang, He [ORNL

    2009-04-01

    Lustre was initiated and funded, almost a decade ago, by the U.S. Department of Energy (DoE) Office of Science and National Nuclear Security Administration laboratories to address the need for an open source, highly-scalable, high-performance parallel filesystem on by then present and future supercomputing platforms. Throughout the last decade, it was deployed over numerous medium-to-large-scale supercomputing platforms and clusters, and it performed and met the expectations of the Lustre user community. As it stands at the time of writing this document, according to the Top500 list, 15 of the top 30 supercomputers in the world use Lustre filesystem. This report aims to present a streamlined overview on how Lustre works internally at reasonable details including relevant data structures, APIs, protocols and algorithms involved for Lustre version 1.6 source code base. More importantly, it tries to explain how various components interconnect with each other and function as a system. Portions of this report are based on discussions with Oak Ridge National Laboratory Lustre Center of Excellence team members and portions of it are based on our own understanding of how the code works. We, as the authors team bare all responsibilities for all errors and omissions in this document. We can only hope it helps current and future Lustre users and Lustre code developers as much as it helped us understanding the Lustre source code and its internal workings.

  1. Adrenergic and histaminergic neural interactions in dog paws

    Energy Technology Data Exchange (ETDEWEB)

    Baker, C.H.; Davis, D.L.; Sutton, E.T.; Lindsey, B.G. (Univ. of South Florida, Tampa (USA))

    1988-09-01

    The mechanisms underlying the vascular responses of superficial fibular nerve stimulation (SFNS) have not been defined. Right hindpaws of anesthetized heparinized dogs were vascularly and neurally isolated, enclosed in a volume recorder, and perfused with controlled pressure. Vascular volume (VV) ({sup 131}I-labeled albumin) and rate of tissue volume changes (V{sub T}) (plethysmography) were determined. SFNS increased blood flow resistance, reduced capillary filtration coefficient (CFC) and permeability-surface area product (PS) of {sup 86}Rb, increased VV, and reduced {sup 131}I-albumin recovery. SFNS during terbutaline increased resistance, CFC, PS, and VV were unchanged, {sup 131}I-albumin recovery was complete, and V{sub T} increased at one-fourth the control rate. Phentolamine and yohimbine blocked all responses to SFNS. Prazosin with SFNS attenuated hemodynamic changes and V{sub T} increased to two-thirds of control, decreased VV, albumin, and Rb recovery but not PS and CFC. SFNS during pyrilamine maleate reduced V{sub T} increase to two-thirds of control rate and blocked decreases in PS and CFC. Metiamide did not change the SFNS responses, except to reduce vascular volume and V{sub T}. The combined histamine H{sub 1} and H{sub 2} blockers reduced V{sub T} increase to one-third of control and attenuated albumin loss, prevented histamine dilation, attenuated vasopressin and norepinephrine but not angiotensin constriction. SFNS stimulation increased precapillary resistance by {alpha}{sub 1}- and {alpha}{sub 2}-receptors and venous resistance by {alpha}{sub 2}-receptors and increased permeability by histamine release from endothelium.

  2. Adrenergic and histaminergic neural interactions in dog paws

    International Nuclear Information System (INIS)

    Baker, C.H.; Davis, D.L.; Sutton, E.T.; Lindsey, B.G.

    1988-01-01

    The mechanisms underlying the vascular responses of superficial fibular nerve stimulation (SFNS) have not been defined. Right hindpaws of anesthetized heparinized dogs were vascularly and neurally isolated, enclosed in a volume recorder, and perfused with controlled pressure. Vascular volume (VV) ( 131 I-labeled albumin) and rate of tissue volume changes (V T ) (plethysmography) were determined. SFNS increased blood flow resistance, reduced capillary filtration coefficient (CFC) and permeability-surface area product (PS) of 86 Rb, increased VV, and reduced 131 I-albumin recovery. SFNS during terbutaline increased resistance, CFC, PS, and VV were unchanged, 131 I-albumin recovery was complete, and V T increased at one-fourth the control rate. Phentolamine and yohimbine blocked all responses to SFNS. Prazosin with SFNS attenuated hemodynamic changes and V T increased to two-thirds of control, decreased VV, albumin, and Rb recovery but not PS and CFC. SFNS during pyrilamine maleate reduced V T increase to two-thirds of control rate and blocked decreases in PS and CFC. Metiamide did not change the SFNS responses, except to reduce vascular volume and V T . The combined histamine H 1 and H 2 blockers reduced V T increase to one-third of control and attenuated albumin loss, prevented histamine dilation, attenuated vasopressin and norepinephrine but not angiotensin constriction. SFNS stimulation increased precapillary resistance by α 1 - and α 2 -receptors and venous resistance by α 2 -receptors and increased permeability by histamine release from endothelium

  3. Understanding the supply chain

    Directory of Open Access Journals (Sweden)

    Aćimović Slobodan

    2006-01-01

    Full Text Available Supply chain management represents new business philosophy and includes strategically positioned and much wider scope of activity in comparison with its "older brother" - management of logistics. Philosophy of the concept of supply chain is directed to more coordination of key business functions of every link in distribution chain in the process of organization of the flow of both goods and information, while logistic managing instruments are focused on internal optimum of flows of goods and information within one company. Applying the concept of integrated supply chain among several companies makes the importance of operative logistics activity even greater on the level of one company, thus advancing processes of optimum and coordination within and between different companies and confirms the importance of logistics performances for the company’s profitability. Besides the fact that the borders between companies are being deleted, this concept of supply chain in one distribution channel influences increasing of importance of functional, i.e. traditional business managing approaches but instead it points out the importance of process managing approaches. Although the author is aware that "there is nothing harder, more dangerous and with uncertain success, but to find a way for introducing some novelties (Machiavelli, it would be even his additional stimulation for trying to bring closer the concept and goals of supply chain implementation that are identified in key, relevant, modern, theoretical and consulting approaches in order to achieve better understanding of the subject and faster implementation of the concept of supply chain management by domestic companies.

  4. Understanding the Mechanism of SiC Plasma-Enhanced Chemical Vapor Deposition (PECVD) and Developing Routes toward SiC Atomic Layer Deposition (ALD) with Density Functional Theory.

    Science.gov (United States)

    Filatova, Ekaterina A; Hausmann, Dennis; Elliott, Simon D

    2018-04-17

    Understanding the mechanism of SiC chemical vapor deposition (CVD) is an important step in investigating the routes toward future atomic layer deposition (ALD) of SiC. The energetics of various silicon and carbon precursors reacting with bare and H-terminated 3C-SiC (011) are analyzed using ab initio density functional theory (DFT). Bare SiC is found to be reactive to silicon and carbon precursors, while H-terminated SiC is found to be not reactive with these precursors at 0 K. Furthermore, the reaction pathways of silane plasma fragments SiH 3 and SiH 2 are calculated along with the energetics for the methane plasma fragments CH 3 and CH 2 . SiH 3 and SiH 2 fragments follow different mechanisms toward Si growth, of which the SiH 3 mechanism is found to be more thermodynamically favorable. Moreover, both of the fragments were found to show selectivity toward the Si-H bond and not C-H bond of the surface. On the basis of this, a selective Si deposition process is suggested for silicon versus carbon-doped silicon oxide surfaces.

  5. Funcionamiento diferencial del item en la evaluación internacional PISA. Detección y comprensión. [Differential Item Functioning in the PISA Project: Detection and Understanding

    Directory of Open Access Journals (Sweden)

    Paula Elosua

    2006-08-01

    Full Text Available This report analyses the differential item functioning (DIF in the Programme for Indicators of Student Achievement PISA2000. The items studied are coming from the Reading Comprehension Test. We analyzed the released items from this year because we wanted to join the detection of DIF and its understanding. The reference group is the sample of United Kingdom and the focal group is the Spanish sample. The procedures of detection are Mantel-Haenszel, Logistic Regression and the standardized mean difference, and their extensions for polytomous items. Two items were flagged and the post-hoc analysis didn’t explain the causes of DIF entirely. Este trabajo analiza el funcionamiento diferencial del ítem (FDI de la prueba de comprensión lectora de la evaluación PISA2000 entre la muestras del Reino Unido y España. Se estudian los ítems liberados con el fin de aunar las fases de detección del FDI con la comprensión de sus causas. En la fase de detección se comparan los resultados de los procedimientos Mantel-Haenszel, Regresión Logística y Medias Estandarizadas en sus versiones para ítems dicotómicos y politómicos. Los resultados muestran que dos ítems presentan funcionamiento diferencial aunque el estudio post-hoc llevado a cabo sobre su contenido no ha podido precisar sus causas.

  6. Understanding the function and performance of carbon-enhanced lead-acid batteries : milestone report for the DOE Energy Storage Systems program (FY11 Quarter 1: October through December 2010).

    Energy Technology Data Exchange (ETDEWEB)

    Shane, R. (East Penn Manufacturing, Lyon Station, PA); Enos, David George; Hund, Thomas D.

    2011-05-01

    This report describes the status of research being performed under CRADA No. SC10/01771.00 (Lead/Carbon Functionality in VRLA Batteries) between Sandia National Laboratories and East Penn Manufacturing, conducted for the U.S. Department of Energy's Energy Storage Systems Program. The Quarter 1 Milestone was completed on time. The milestone entails conducting a thorough literature review to establish the current level of understanding of the mechanisms through which carbon additions to the negative active material improve valve-regulated lead-acid (VRLA) batteries. Most studies have entailed phenomenological research observing that the carbon additions prevent/reduce sulfation of the negative electrode; however, no understanding is available to provide insight into why certain carbons are successful while others are not. Impurities were implicated in one recent review of the electrochemical behavior of carbon additions. Four carbon samples have been received from East Penn Manufacturing and impurity contents have been analyzed. Carbon has been explored as an addition to lead-acid battery electrodes in a number of ways. Perhaps the most notable to date has been the hybrid 'Ultrabattery' developed by CSIRO where an asymmetric carbon-based electrochemical capacitor is combined with a lead-acid battery into a single cell, dramatically improving high-rate partial-state-of-charge (HRPSoC) operation. As illustrated below, the 'Ultrabattery' is a hybrid device constructed using a traditional lead-acid battery positive plate (i.e., PbO{sub 2}) and a negative electrode consisting of a carbon electrode in parallel with a lead-acid negative plate. This device exhibits a dramatically improved cycle life over traditional VRLA batteries, as well as increased charge power and charge acceptance. The 'Ultrabattery' has been produced successfully by both The Furukawa Battery Co. and East Penn Manufacturing. An example illustrating the dramatic

  7. Metaphor, skepticism, understanding Metaphor, skepticism, understanding

    Directory of Open Access Journals (Sweden)

    Helena Martins

    2010-05-01

    Full Text Available

    This paper examines the idea that metaphor is a basic cognitive tool from a Wittgensteinian point of view. One specific aspect of Wittgenstein’s legacy is explored, namely his account of verbal understanding. Two interconnected and notoriously difficult features of this account are highlighted and discussed: the idea that linguistic understanding is not an event or a process, but an “abiding condition” (Philosophical Investigations, §143-84; and the idea that neither the meaning of a linguistic expression nor our understanding of it can ever go beyond our capacity of explaining it (Philosophical Investigations, §75. This perspective is shown to be particularly apt in reflecting upon the virtues of metaphor as a means of understanding, especially because it allows for the avoidance of both essentialist and skeptical accounts.

    This paper examines the idea that metaphor is a basic cognitive tool from a Wittgensteinian point of view. One specific aspect of Wittgenstein’s legacy is explored, namely his account of verbal understanding. Two interconnected and notoriously difficult features of this account are highlighted and discussed: the idea that linguistic understanding is not an event or a process, but an “abiding condition” (Philosophical Investigations, §143-84; and the idea that neither the meaning of a linguistic expression nor our understanding of it can ever go beyond our capacity of explaining it (Philosophical Investigations, §75. This perspective is shown to be particularly apt in reflecting upon the virtues of metaphor as a means of understanding, especially because it allows for the avoidance of both essentialist and skeptical accounts

  8. Understanding the fundamental mechanisms of biofilms development and dispersal: BIAM (Biofilm Intensity and Architecture Measurement), a new tool for studying biofilms as a function of their architecture and fluorescence intensity.

    Science.gov (United States)

    Baudin, Marine; Cinquin, Bertrand; Sclavi, Bianca; Pareau, Dominique; Lopes, Filipa

    2017-09-01

    Confocal laser scanning microscopy (CLSM) is one of the most relevant technologies for studying biofilms in situ. Several tools have been developed to investigate and quantify the architecture of biofilms. However, an approach to quantify correctly the evolution of intensity of a fluorescent signal as a function of the structural parameters of a biofilm is still lacking. Here we present a tool developed in the ImageJ open source software that can be used to extract both structural and fluorescence intensity from CLSM data: BIAM (Biofilm Intensity and Architecture Measurement). This is of utmost significance when studying the fundamental mechanisms of biofilm growth, differentiation and development or when aiming to understand the effect of external molecules on biofilm phenotypes. In order to provide an example of the potential of such a tool in this study we focused on biofilm dispersion. cis-2-Decenoic acid (CDA) is a molecule known to induce biofilm dispersion of multiple bacterial species. The mechanisms by which CDA induces dispersion are still poorly understood. To investigate the effects of CDA on biofilms, we used a reporter strain of Escherichia coli (E. coli) that expresses the GFPmut2 protein under control of the rrnBP1 promoter. Experiments were done in flow cells and image acquisition was made with CLSM. Analysis carried out using the new tool, BIAM, indicates that CDA affects the fluorescence intensity of the biofilm structures as well as biofilm architectures. Indeed, our results demonstrate that CDA removes more than 35% of biofilm biovolume and suggest that it results in an increase of the biofilm's mean fluorescence intensity (MFI) by more than 26% compared to the control biofilm in the absence of CDA. Copyright © 2017. Published by Elsevier B.V.

  9. Understanding Identity and Organizations

    DEFF Research Database (Denmark)

    Christensen, Lars Thøger

    2013-01-01

    The article reviews the book "Understanding Identity and Organizations," by Kate Kenny, Andrea Whitle, and Hugh Wilmott.......The article reviews the book "Understanding Identity and Organizations," by Kate Kenny, Andrea Whitle, and Hugh Wilmott....

  10. Understanding Hereditary Angioedema

    Science.gov (United States)

    ... Allergy Library ▸ Understanding Hereditary Angioedema Share | Understanding Hereditary Angioedema This article has been reviewed by Thanai Pongdee, MD, FAAAAI Hereditary Angioedema (HAE) is a rare genetic condition. People with ...

  11. Understanding Cancer Prognosis

    Medline Plus

    Full Text Available ... Prognosis Questions to Ask about Your Diagnosis Research Understanding Cancer Prognosis Oncologist Anthony L. Back, M.D., ... find our information on Coping With Cancer helpful. Understanding Statistics About Survival Doctors estimate prognosis by using ...

  12. Understanding in mathematics

    CERN Document Server

    Sierpinska, Anna

    1994-01-01

    The concept of understanding in mathematics with regard to mathematics education is considered in this volume, the main problem for mathematics teachers being how to facilitate their students'' understanding of the mathematics being taught.

  13. Understanding Food Labels

    Science.gov (United States)

    ... Healthy eating for girls Understanding food labels Understanding food labels There is lots of info on food ... need to avoid because of food allergies. Other food label terms top In addition to the Nutrition ...

  14. Paradoxical function of orexin/hypocretin circuits in a mouse model of Huntington's disease

    Science.gov (United States)

    Williams, Rhîannan H.; Morton, A. Jennifer; Burdakov, Denis

    2018-01-01

    Huntington's disease (HD) is a neurodegenerative disorder involving progressive motor disturbances, cognitive decline, and desynchronized sleep–wake rhythms. Recent studies revealed that restoring normal sleep–wake cycles can improve cognitive function in HD mice, suggesting that some sleep/wake systems remain operational and thus represent potential therapeutic targets for HD. Hypothalamic neurons expressing orexins/hypocretins (orexin neurons) are fundamental orchestrators of arousal in mammals, but it is unclear whether orexin circuits operate normally in HD. Here we analyzed the electrophysiology, histology, and gene expression of orexin circuits in brain slices from R6/2 mice, a transgenic model of HD with a progressive neurological phenotype. We report that in R6/2 mice, the size of an electrically distinct subpopulation of orexin neurons is reduced, as is the number of orexin-immunopositive cells in some hypothalamic regions. R6/2 orexin cells display altered glutamatergic inputs, and have an abnormal circadian profile of activity, despite normal circadian rhythmicity of the suprachiasmatic nucleus (SCN), the “master clock” of the brain. Nevertheless, even at advanced stages of HD, intrinsic firing properties of orexin cells remain normal and suppressible by serotonin, noradrenaline, and glucose. Furthermore, histaminergic neurons (key cells required for the propagation of orexin-induced arousal) also display normal responses to orexin. Together, these data suggest that the orexin system remains functional and modifiable in HD mice, although its circadian activity profile is disrupted and no longer follows that of the SCN. PMID:21324360

  15. Valuation of Understanding

    DEFF Research Database (Denmark)

    Wiberg, Merete

    An important aim for the teacher in Higher Education is that students, in order to learn, achieve understanding in terms of being able to handle knowledge in a certain way. In this paper focus will be on understanding as a phenomenon which is permeated with values of what good understanding might...... be. Understanding is to be discussed as a phenomenon which in its definition is relative to the paradigm of educational thinking in which it is embedded. Paradigms of valuation of understanding in higher education will be viewed from two perspectives: An anglosaxon curriculum studies tradition...

  16. Idiom understanding in people with Asperger syndrome/high functioning autism Compreensão de expressões idiomáticas em pessoas com síndrome de Asperger/autismo de alto funcionamento

    Directory of Open Access Journals (Sweden)

    Ioannis Vogindroukas

    2011-12-01

    Full Text Available PURPOSE: To extend previous research in the development of idiom comprehension by investigating this ability in children with Asperger Syndrome (AS or with High Functioning Autism (HFA. METHODS: Three groups participated in the study. The first group consisted of 27 children with AS/HFA (mean age 11.3 years and the other two consisted of typically developing children and adults, respectively. The Comprehension Test of Idiomatic Phrases (CTIP was administered to all participants. RESULTS: Children with AS/HFA had lower performance compared to the other two groups. No difference was found in the performance between the two typically developing groups. Also, there was no significant correlation between the IQ and the performance for the children with AS/HFA, while positive correlations were revealed between performance and age for the two groups of children. CONCLUSION: The results provide further evidence that children with AS/HFA have difficulties in understanding idioms and they confirm their tendency to make literal interpretations. These impairments are irrelevant to their intelligence and they affect their communication with others. The understanding of these difficulties is important in order to find ways to limit the confusion and the misinterpretations which are observed during the communicative acts with this clinic group.OBJETIVO: Ampliar pesquisas anteriores a respeito do desenvolvimento da compreensão de expressões idiomáticas por meio da investigação dessa habilidade em crianças com síndrome de Asperger (AS ou com autismo de alto funcionamento (HFA. MÉTODOS: Três grupos participaram do estudo. O primeiro grupo era composto por 27 crianças com AS/HFA (média de idade 11 anos e 3 meses e os outros dois eram constituídos, respectivamente, por crianças em desenvolvimento típico e adultos. O Teste de Compreensão de Expressões Idiomáticas (CTIP foi aplicado a todos os participantes. RESULTADOS: Crianças com AS/HFA tiveram

  17. Language Games and Musical Understanding

    Directory of Open Access Journals (Sweden)

    Alessandro Arbo

    2013-05-01

    Full Text Available Wittgenstein has often explored language games that have to do with musical objects of different sizes (phrases, themes, formal sections or entire works. These games can refer to a technical language or to common parlance and correspond to different targets. One of these coincides with the intention to suggest a way of conceiving musical understanding. His model takes the form of the invitation to "hear (something as (something": typically, to hear a musical passage as an introduction or as a conclusion or in a certain tonality. However one may ask to what extent or in what terms (literal or metaphorical these procedures, and usually the intervention of language games, is requested by our common ways of understanding music. This article shows through the use of some examples that aspectual perception inherent to musical understanding does not require language games as a necessary condition (although in many cases the link between them seems very strong, in contradiction with the thesis of an essential linguistic character of music. At a basic level, it seems more appropriate to insist on the notion of a game: to understand music means to enter into the orbit of "music games" which show an autonomous functioning. Language games have, however, an important function when we develop this comprehension in the light of the criteria of judgment that substantiate the manner in which music is incorporated in and operates within specific forms of life.

  18. Flexibility in embodied language understanding

    Directory of Open Access Journals (Sweden)

    Roel M Willems

    2011-06-01

    Full Text Available Do people use sensori-motor cortices to understand language? Here we review neurocognitive studies of language comprehension in healthy adults and evaluate their possible contributions to theories of language in the brain. We start by sketching the minimal predictions that an embodied theory of language understanding makes for empirical research, and then survey studies that have been offered as evidence for embodied semantic representations. We explore four debated issues: first, does activation of sensori-motor cortices during action language understanding imply that action semantics relies on mirror neurons? Second, what is the evidence that activity in sensori-motor cortices plays a functional role in understanding language? Third, to what extent do responses in perceptual and motor areas depend on the linguistic and extra-linguistic context? And finally, can embodied theories accommodate language about abstract concepts? Based on the available evidence, we conclude that sensori-motor cortices are activated during a variety of language comprehension tasks, for both concrete and abstract language. Yet, this activity depends on the context in which perception and action words are encountered. Although modality-specific cortical activity is not a sine qua non of language processing even for language about perception and action, sensori-motor regions of the brain appear to make functional contributions to the construction of meaning, and should therefore be incorporated into models of the neurocognitive architecture of language.

  19. Understanding quantum physics

    International Nuclear Information System (INIS)

    Spillner, Vera

    2011-01-01

    This thesis presents a bundle definition for 'scientific understanding' through which the empirically equivalent interpretations of quantum mechanics can be evaluated with respect to the understanding they generate. The definition of understanding is based on a sufficient and necessary criterion, as well as a bundle of conditions - where a theory can be called most understandable whenever it fulfills the highest number of bundle criteria. Thereby the definition of understanding is based on the one hand on the objective number of criteria a theory fulfills, as well as, on the other hand, on the individual's preference of bundle criteria. Applying the definition onto three interpretations of quantum mechanics, the interpretation of David Bohm appears as most understandable, followed by the interpretation of Tim Maudlin and the Kopenhagen interpretation. These three interpretations are discussed in length in my thesis. (orig.)

  20. Understanding Cancer Prognosis

    Medline Plus

    Full Text Available ... our information on Coping With Cancer helpful. Understanding Statistics About Survival Doctors estimate prognosis by using statistics that researchers have collected over many years about ...

  1. Understanding cancer onset

    DEFF Research Database (Denmark)

    Veldhuis, Djuke

    2015-01-01

    Researchers in Malaysia analysed the genomes of people with a rare genetic disorder to better understand people’s predisposition to cancer across generations.......Researchers in Malaysia analysed the genomes of people with a rare genetic disorder to better understand people’s predisposition to cancer across generations....

  2. Understanding Menstrual Migraine.

    Science.gov (United States)

    Calhoun, Anne H

    2018-04-01

    Menstrual-related migraine is very prevalent, very disabling, yet very easy to manage given a good understanding of its cause. This article is intended to help with that understanding and to enable headache specialists to prescribe or create effective hormonal preventives of menstrual-related migraine. © 2018 American Headache Society.

  3. Understanding the visual resource

    Science.gov (United States)

    Floyd L. Newby

    1971-01-01

    Understanding our visual resources involves a complex interweaving of motivation and cognitive recesses; but, more important, it requires that we understand and can identify those characteristics of a landscape that influence the image formation process. From research conducted in Florida, three major variables were identified that appear to have significant effect...

  4. Understanding Cancer Prognosis

    Medline Plus

    Full Text Available ... Questions to Ask about Your Diagnosis Research Understanding Cancer Prognosis Oncologist Anthony L. Back, M.D., a ... for provider care teams (PDF-210KB). Understanding Your Cancer Prognosis Video View this video on YouTube. Three ...

  5. Supply chain management: a framework of understanding

    OpenAIRE

    Du Toit, Deirdre; Vlok, Pieter-Jan

    2014-01-01

    The topic of supply chain management (SCM) is complex to understand because it encompasses many different flows of activities, components, functions, and role-players. The literature is scattered across multiple functions, varies in scope, and is often confined to certain elements within SCM. This article aims to provide a literature overview of SCM. It is explained with the aid of a newly-developed framework of understanding that offers a graphical representation of the term. It unifies and ...

  6. Biomedical image understanding methods and applications

    CERN Document Server

    Lim, Joo-Hwee; Xiong, Wei

    2015-01-01

    A comprehensive guide to understanding and interpreting digital images in medical and functional applications Biomedical Image Understanding focuses on image understanding and semantic interpretation, with clear introductions to related concepts, in-depth theoretical analysis, and detailed descriptions of important biomedical applications. It covers image processing, image filtering, enhancement, de-noising, restoration, and reconstruction; image segmentation and feature extraction; registration; clustering, pattern classification, and data fusion. With contributions from ex

  7. Understanding Prenatal Tests

    Science.gov (United States)

    ... Navigation Bar Home Current Issue Past Issues Understanding Prenatal Tests Past Issues / Winter 2008 Table of Contents ... be done before pregnancy or at the first prenatal visit. If there is Rh incompatibility, treatments can ...

  8. Understanding Cancer Prognosis

    Medline Plus

    Full Text Available ... Reporting & Auditing Grant Transfer Grant Closeout Contracts & Small Business Training Cancer Training at NCI (Intramural) Funding for ... disease will go for you is called prognosis. It can be hard to understand what prognosis means ...

  9. Understanding health insurance plans

    Science.gov (United States)

    ... medlineplus.gov/ency/patientinstructions/000879.htm Understanding health insurance plans To use the sharing features on this ... for you and your family. Types of Health Insurance Plans Depending on how you get your health ...

  10. Thermometers: Understand the Options

    Science.gov (United States)

    ... the options Thermometers come in a variety of styles. Understand the different types of thermometers and how ... MA. Fever in infants and children: Pathophysiology and management. http://www.uptodate.com/home. Accessed July 23, ...

  11. Understanding cardiovascular disease

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/patientinstructions/000759.htm Understanding cardiovascular disease To use the sharing features on this page, ... lead to heart attack or stroke. Types of Cardiovascular Disease Coronary heart disease (CHD) is the most common ...

  12. Tinnitus: Understanding the Facts

    Science.gov (United States)

    American Tinnitus Association Donate Become A Member Member Login Find A Provider Search form Search Menu Close Understanding The Facts Managing Your Tinnitus Research Toward A Cure About Us Initiatives News & ...

  13. Economics and International Understanding.

    Science.gov (United States)

    Chandra, Ramesh

    1983-01-01

    A methodology linking the teaching of economics to the promotion of international understanding is discussed. The content of a course dealing with the new international economic order is examined. (Author/RM)

  14. Understanding the New Economy.

    Science.gov (United States)

    Morrell, Louis R.

    2001-01-01

    Asserts that while the Nasdaq bubble did burst, the new economy is real and that failure to understand the rules of the digital economy can lead to substandard investment portfolio performance. Offers guidelines for higher education institutional investors. (EV)

  15. Understanding Cancer Prognosis

    Medline Plus

    Full Text Available ... side effects from the cancer treatments you received. Video Series This video series offers the perspectives of ... care teams (PDF-210KB). Understanding Your Cancer Prognosis Video View this video on YouTube. Three cancer patients ...

  16. Understanding the DASH diet

    Science.gov (United States)

    ... medlineplus.gov/ency/patientinstructions/000784.htm Understanding the DASH diet To use the sharing features on this page, please enable JavaScript. The DASH diet is low in salt and rich in fruits, ...

  17. Understanding Cancer Prognosis

    Medline Plus

    Full Text Available ... Managing Cancer Care Finding Health Care Services Costs & Medical Information Advance Directives Using Trusted Resources Understanding Cancer ... Care Finding Health Care Services Managing Costs and Medical Information Advance Directives Using Trusted Resources Cancer Types ...

  18. Understanding Cancer Prognosis

    Medline Plus

    Full Text Available ... Care Finding Health Care Services Costs & Medical Information Advance Directives Using Trusted Resources Understanding Cancer What Is ... Health Care Services Managing Costs and Medical Information Advance Directives Using Trusted Resources Cancer Types Adolescents and ...

  19. Understanding Cancer Prognosis

    Medline Plus

    Full Text Available ... Research Managing Cancer Care Finding Health Care Services Costs & Medical Information Advance Directives Using Trusted Resources Understanding ... Managing Cancer Care Finding Health Care Services Managing Costs and Medical Information Advance Directives Using Trusted Resources ...

  20. Understanding the Opioid Epidemic

    Science.gov (United States)

    ... Search Form Controls Cancel Submit Search The CDC Opioid Overdose Note: Javascript is disabled or is not ... message, please visit this page: About CDC.gov . Opioid Overdose Opioid Basics Understanding the Epidemic Commonly Used ...

  1. Understanding Cancer Prognosis

    Medline Plus

    Full Text Available ... doctor to give you an accurate prognosis. Understanding the Difference Between Cure and Remission Cure means that ... about her colorectal cancer prognosis. Diving Out of the Dark View this video on YouTube. Andrew wants ...

  2. Understanding your hospital bill

    Science.gov (United States)

    ... medlineplus.gov/ency/patientinstructions/000881.htm Understanding your hospital bill To use the sharing features on this ... help you save money. Charges Listed on Your Hospital Bill A hospital bill will list the major ...

  3. Understanding Blood Pressure Readings

    Science.gov (United States)

    ... Artery Disease Venous Thromboembolism Aortic Aneurysm More Understanding Blood Pressure Readings Updated:Feb 19,2018 What do your ... this chart: English | Spanish | Traditional Chinese Enter Your Blood Pressure Systolic mm Hg (upper #) Diastolic mm Hg (lower #) ...

  4. Understanding Conflict?...Maybe!

    OpenAIRE

    Anthony P. Johnson

    2008-01-01

    The premise of this paper is the study in the field of conflict andconflict resolution and that conflict and conflict resolution are usefulareas of focus in order to better understand human behavior. Additionally,I will present data that will highlight the notion that conflict is not in itselfa bad thing and that conflict has the capability to be utilized as a vehiclefor understanding the many contradictions that are necessarily present inour efforts to be social beings.

  5. Understanding Family Diversity

    OpenAIRE

    Knowles, G

    2012-01-01

    This essential text will help students and those already working with children to understand both theoretically and practically, what may constitute a ‘family’. It explores how to build relationships with a child’s family to ensure early years settings and schools are working in partnership with children’s home environments, thereby supporting the best possible learning outcomes for children. It will help the reader to develop their skills, knowledge and understanding of their professional pr...

  6. Understanding Polymer-Cell Attachment.

    Science.gov (United States)

    Venturato, Andrea; MacFarlane, Gillian; Geng, Jin; Bradley, Mark

    2016-12-01

    The development of polymeric materials with cell adhesion abilities requires an understanding of cell-surface interactions which vary with cell type. To investigate the correlation between cell attachment and the nature of the polymer, a series of random and block copolymers composed of 2-(dimethylamino)ethyl acrylate and ethyl acrylate are synthesized through single electron transfer living radical polymerization. The polymers are synthesized with highly defined and controlled monomer compositions and exhibited narrow polydispersity indices. These polymers are examined for their performance in the attachment and growth of HeLa and HEK cells, with attachment successfully modeled on monomer composition and polymer chain length, with both cell lines found to preferentially attach to moderately hydrophobic functional materials. The understanding of the biological-material interactions assessed in this study will underpin further investigations of engineered polymer scaffolds with predictable cell binding performance. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Understand electrical and electronics maths

    CERN Document Server

    Bishop, Owen

    1993-01-01

    Understand Electrical and Electronics Maths covers elementary maths and the aspects of electronics. The book discusses basic maths including quotients, algebraic fractions, logarithms, types of equations and balancing of equations. The text also describes the main features and functions of graphs and the solutions to simpler types of electronics problems. The book then tackles the applications of polar coordinates in electronics, limits, differentiation and integration, and the applications of maths of rates of change in electronics. The activities of an electronic circuit; techniques of math

  8. Understanding collaborative partnerships between farmers

    DEFF Research Database (Denmark)

    Asai, Masayasu

    arrangements, either as family or neighbors, or through their local or professional networks. Social relationships are also shown to play an important role in shaping the functions of partnerships, expressed for example in the burden-sharing of manure transportation and spreading, frequency of communication......, duration of the partnership and transport distance. The most important aspects of farmers' perception of successful collaborative arrangements seem to be trust, continuity, flexibility and accessibility. These findings supplement the understanding of farmer collaboration based on spatial-economic models...

  9. Understanding users in product development

    DEFF Research Database (Denmark)

    Geert Jensen, Birgitte

    2012-01-01

    , the guideline contain a step by step process to develop easy‐to‐open packaging. The guideline is constructed in a way that allows the enterprise to pick and choose in respect to the enterprise´s needs and competences. The main focus in the development of the guidelines has been to produce a tool that function...... observations is a tool for user understanding and that the first step towards better packaging, goes through consensus in the organization regarding the need for more easy‐opening packaging....

  10. The production of understanding.

    Science.gov (United States)

    Link, Bruce G

    2003-12-01

    While there is little doubt that sociological theory and research has had an important impact on the way people think about health and health care, mental health and medical sociologists are often confronted with challenges concerning the utility of the work that they do. Among the doubters are deans, funding agencies and family members. We are challenged by the ascendency of biological interpretations of human behaviors, by the incompatibility between the contextual view we prefer and the very strong individualistic orientation of our culture, and by the fact that we do not have an applied arm that trains the professionals who treat health and mental-health conditions. How do we respond to this challenge? The title of this paper gives a short answer: "The Production of Understanding." I propose that a powerful but under-recognized value of our work is the generation of explanations about health and mental health matters that help people understand the other side of an "us"/"them" divide. We produce understanding in a context in which misunderstanding is regularly constructed by powerful people who offer victim-blaming explanations for the circumstances experienced by people with less power. The production of understanding serves as an important counterbalance to this tendency. Our work shapes the way people think about problems related to health and mental health, limits the power of inaccurate victim-blaming accounts and provides understanding about why health and mental health are mal-distributed among people from different social circumstances.

  11. Understanding Sex for Sale

    DEFF Research Database (Denmark)

    This book Understanding Sex for Sale: Meanings and Moralities of Sexual Commerce is dedicated to the exploration of the ways in which sex prostitution, sex work or sex for sale are taken for granted by particularly looking at how the relation between sex and money is interpreted and enacted....... This interdisciplinary book aims to understand how prostitution, sex work or sex for sale are defined, delineated, contested and understood in different places and times. The book offers contributions from a number of scholars who, based on their on their own research, discuss on going theoretical issues and analytical...... challenges Some chapters focuses on how prostitution, sex work or sex for sale have been regulated by the authorities and what understandings this regulation builds on. Other chapters investigate the experiences of the sex workers and sex buyers asking how these actors adjust to or resist the categorisation...

  12. Understanding pastoral mobility

    DEFF Research Database (Denmark)

    Adriansen, Hanne Kirstine

    2008-01-01

    Based on a case study from Sahelian Senegal, this paper analyses how various actors perceive the importance of pastoral mobility and presents issues of importance for understanding the use of mobility among Fulani of Ferlo. One knowledge system is a scientific one, the 'new rangeland paradigm...... territory, which they consider their place, but are unwilling to employ large-scale mobility themselves. Mobility is not of importance for their ethnic identity and some use paid herders to care for their livestock. By looking at both knowledge systems, we achieve a better understanding of pastoral mobility...

  13. Towards a comprehensive understanding of emerging dynamics and function of pancreatic islets: A complex network approach. Comment on "Network science of biological systems at different scales: A review" by Gosak et al.

    Science.gov (United States)

    Loppini, Alessandro

    2018-03-01

    Complex network theory represents a comprehensive mathematical framework to investigate biological systems, ranging from sub-cellular and cellular scales up to large-scale networks describing species interactions and ecological systems. In their exhaustive and comprehensive work [1], Gosak et al. discuss several scenarios in which the network approach was able to uncover general properties and underlying mechanisms of cells organization and regulation, tissue functions and cell/tissue failure in pathology, by the study of chemical reaction networks, structural networks and functional connectivities.

  14. Understanding Cancer Prognosis

    Medline Plus

    Full Text Available ... Your Diagnosis Research Understanding Cancer Prognosis Oncologist Anthony L. Back, M.D., a national expert on doctor- ... Centered Approach View this video on YouTube. Anthony L. Back, M.D., coaches other oncologists about how ...

  15. Understanding Inclusion in Cyprus

    Science.gov (United States)

    Mamas, Christoforos

    2013-01-01

    This paper provides a framework for understanding inclusion in Cyprus. The evidence base is the result of a six-month qualitative research study in five Cypriot mainstream primary schools. Despite the rhetoric in favour of inclusion, it seems that the Cypriot educational system is still highly segregating in its philosophy and does not fully…

  16. Understanding regime shifts

    DEFF Research Database (Denmark)

    Heymann, Matthias; Nielsen, Kristian Hvidtfelt

    ”. Danish wind power development is all the more surprising, as the innovation process in wind technology was carried to a large extent by non-academic craftsmen and political activists. Many features of this innovation story have been investigated and that research makes it possible to summarize...... the current understanding of the regime shift....

  17. Understanding land administration systems

    DEFF Research Database (Denmark)

    P. Williamson, Ian; Enemark, Stig; Wallace, Judy

    2008-01-01

    This paper introduces basic land administration theory and highlights four key concepts that are fundamental to understanding modern land administration systems. Readers may recall the first part of the paper in October issue of Coordinates. Here is the concluding part that focuses on the changing...

  18. Understanding the bubbles

    DEFF Research Database (Denmark)

    Turcan, Romeo V.

    all boils down to the role pricing plays vis-à-vis the emergence of a new venture and its perceived value. Being in the midst of the global economic crisis provides us with a unique opportunity to refine the proposed model, especially by understanding its temporal and contextual boundaries....

  19. Teachers' Understandings of Probability

    Science.gov (United States)

    Liu, Yan; Thompson, Patrick

    2007-01-01

    Probability is an important idea with a remarkably wide range of applications. However, psychological and instructional studies conducted in the last two decades have consistently documented poor understanding of probability among different populations across different settings. The purpose of this study is to develop a theoretical framework for…

  20. Understanding Ocean Acidification

    Science.gov (United States)

    National Oceanic and Atmospheric Administration, 2011

    2011-01-01

    This curriculum module is designed for students who are taking high school chemistry. Students should already have some experience with the following: (1) Understanding and reading the pH scale; (2) Knowledge of the carbon cycle; (3) Using scientific notation to express large and small values; and (4) Reading chemical equations. This curriculum…

  1. Phun Week: Understanding Physiology

    Science.gov (United States)

    Limson, Mel; Matyas, Marsha Lakes

    2009-01-01

    Topics such as sports, exercise, health, and nutrition can make the science of physiology relevant and engaging for students. In addition, many lessons on these topics, such as those on the cardiovascular, respiratory, and digestive systems, align with national and state life science education standards. Physiology Understanding Week (PhUn…

  2. Understanding Organizational Advantage

    DEFF Research Database (Denmark)

    Stea, Diego; Linder, Stefan; Foss, Nicolai Juul

    2015-01-01

    The attention-based view (ABV) of the firm highlights the role of decision makers’ attention in firm behavior. The ABV vastly improves our understanding of decision makers’ focus of attention; how that focus is situated in an organization’s procedural and communication channels; and how the distr......The attention-based view (ABV) of the firm highlights the role of decision makers’ attention in firm behavior. The ABV vastly improves our understanding of decision makers’ focus of attention; how that focus is situated in an organization’s procedural and communication channels; and how...... the distribution of the focus of attention among decision makers participating in those procedural and communication channels affects their understanding of a situation, their motivation to act, and, ultimately, their behavior. Significant progress has been made in recent years in refining and extending the ABV....... However, the role of individual differences in the capacity to read other people’s desires, intentions, knowledge, and beliefs that is, the theory of mind (ToM) has remained on the sidelines. The ToM is a natural complement to the ABV. In this study, we explore how the ToM allows for an understanding...

  3. Understanding ADHD through entification

    DEFF Research Database (Denmark)

    Nielsen, Mikka

    with adults diagnosed with ADHD, I illustrate how the process of entification (transforming a trait, temperament, emotion, or some other psychological phenomenon into a thing or agent) can be a way to understand, accept and handle the symptoms of ADHD. In this context, ADHD is perceived on the one hand...

  4. Measuring Spreadsheet Formula Understandability

    NARCIS (Netherlands)

    Hermans, F.F.J.; Pinzger, M.; Van Deursen, A.

    2012-01-01

    Spreadsheets are widely used in industry, because they are flexible and easy to use. Often they are used for business-critical applications. It is however difficult for spreadsheet users to correctly assess the quality of spreadsheets, especially with respect to the understandability.

  5. Understanding Cancer Prognosis

    Medline Plus

    Full Text Available ... 1-800-4-CANCER Live Chat Publications Dictionary Menu Contact Dictionary Search About Cancer Causes and Prevention ... source and a link to this page included, e.g., “Understanding Cancer Prognosis was originally published by ...

  6. Text understanding for computers

    NARCIS (Netherlands)

    Kenter, T.M.

    2017-01-01

    A long-standing challenge for computers communicating with humans is to pass the Turing test, i.e., to communicate in such a way that it is impossible for humans to determine whether they are talking to a computer or another human being. The field of natural language understanding — which studies

  7. Interviewing to Understand Strengths

    Science.gov (United States)

    Hass, Michael R.

    2018-01-01

    Interviewing clients about their strengths is an important part of developing a complete understanding of their lives and has several advantages over simply focusing on problems and pathology. Prerequisites for skillfully interviewing for strengths include the communication skills that emerge from a stance of not knowing, developing a vocabulary…

  8. Understanding Intellectual Disability through Rasopathies

    Science.gov (United States)

    Alvaro, San Martín; Rafael, Pagani Mario

    2014-01-01

    Intellectual disability, commonly known as mental retardation in the International Classification of Disease from World Health Organization, is the term that describes an intellectual and adaptive cognitive disability that begins in early life during the developmental period. Currently the term intellectual disability is the preferred one. Although our understanding of the physiological basis of learning and learning disability is poor, a general idea is that such condition is quite permanent. However, investigations in animal models suggest that learning disability can be functional in nature and as such reversible through pharmacology or appropriate learning paradigms. A fraction of the cases of intellectual disability is caused by point mutations or deletions in genes that encode for proteins of the RAS/MAP Kinase signaling pathway known as RASopathies. Here we examined the current understanding of the molecular mechanisms involved in this group of genetic disorders focusing in studies which provide evidence that intellectual disability is potentially treatable and curable. The evidence presented supports the idea that with the appropriate understanding of the molecular mechanisms involved, intellectual disability could be treated pharmacologically and perhaps through specific mechanistic-based teaching strategies. PMID:24859216

  9. Understanding Games as Played

    DEFF Research Database (Denmark)

    Leino, Olli Tapio

    2009-01-01

    Researchers interested in player’s experience would assumedly, across disciplines, agree that the goal behind enquiries into player’s experience is to understand the how games’ features end up affecting the player’s experience. Much of the contemporary interdisciplinary research into player......’s experience leans toward the empirical-scientific, in the forms (neuro)psychology, sociology and cognitive science, to name a few. In such approaches, for example demonstrating correlation between physiological symptoms and an in-game event may amount to ‘understanding’. However, the experience of computer...... game play is a viable topic also for computer game studies within the general tradition of humanities. In such context, the idea of ‘understanding an experience’ invites an approach focusing on the experienced significance of events and objects within computer game play. This focus, in turn, suggests...

  10. Understanding Video Games

    DEFF Research Database (Denmark)

    Heide Smith, Jonas; Tosca, Susana Pajares; Egenfeldt-Nielsen, Simon

    From Pong to PlayStation 3 and beyond, Understanding Video Games is the first general introduction to the exciting new field of video game studies. This textbook traces the history of video games, introduces the major theories used to analyze games such as ludology and narratology, reviews...... the economics of the game industry, examines the aesthetics of game design, surveys the broad range of game genres, explores player culture, and addresses the major debates surrounding the medium, from educational benefits to the effects of violence. Throughout the book, the authors ask readers to consider...... larger questions about the medium: * What defines a video game? * Who plays games? * Why do we play games? * How do games affect the player? Extensively illustrated, Understanding Video Games is an indispensable and comprehensive resource for those interested in the ways video games are reshaping...

  11. Understanding Video Games

    DEFF Research Database (Denmark)

    Heide Smith, Jonas; Tosca, Susana Pajares; Egenfeldt-Nielsen, Simon

    From Pong to PlayStation 3 and beyond, Understanding Video Games is the first general introduction to the exciting new field of video game studies. This textbook traces the history of video games, introduces the major theories used to analyze games such as ludology and narratology, reviews...... larger questions about the medium: * What defines a video game? * Who plays games? * Why do we play games? * How do games affect the player? Extensively illustrated, Understanding Video Games is an indispensable and comprehensive resource for those interested in the ways video games are reshaping...... entertainment and society. A companion website (www.routledge.com/textbooks/9780415977210) features student resources including discussion questions for each chapter, a glossary of key terms, a video game timeline, and links to other video game studies resources for further study....

  12. Understanding China's Transformations

    DEFF Research Database (Denmark)

    Li, Xing

    The objective of this paper is to offer a framework of understanding the dialectical nexus between China's internal evolutions and the external influences with a focus on the century-long "challenge-response" dynamism. That is to explore how external factors helped shaping China's internal...... transformations, i.e. how generations of Chinese have been struggling in responding to the external challenges and attempting to sinicize external political ideas in order to change China from within. Likewise, it is equally important to understand how China's inner transformation contributed to reshaping...... the world. Each time, be it China's dominance or decline, the capitalist world system has to adjust and readjust itself to the opportunities and constraints brought about by the "China factors"....

  13. Understanding nuclear issues

    Energy Technology Data Exchange (ETDEWEB)

    Marx, G. [Department of Atomic Physics, Eoetvoes Univ., Budapest (Hungary)

    1999-09-01

    In our days technological progress for the benefit of society is slowed down by the fact that common citizens (opinion-forming media reporters, journalists, furthermore elected decision-makers) are underinformed about basic numerical facts concerning harms and benefits of high technology. Here a comparative risk study is presented about smoking, ozone hole, global warming, and ionizing radiation. This approach has turned out to be successful in educating the youth in Hungary; because school-going teenagers do understand numbers. (author)

  14. Understanding the spermatozoon.

    Science.gov (United States)

    Neri, Queenie V; Hu, Jennifer; Rosenwaks, Zev; Palermo, Gianpiero D

    2014-01-01

    The former perception of the spermatozoon as a delivery device of the male genome has been expanded to include a new understanding of the cell's complex role in fertilization. Once the spermatozoon reaches the oocyte, it triggers egg activation and orchestrates the stages of pre- and post-fertilization in a preprogrammed pattern while tapping the oocyte's resources in an effort to generate a new life.

  15. Understanding Mediation Support

    OpenAIRE

    Lanz, David; Pring, Jamie; von Burg, Corinne; Zeller, Mathias

    2017-01-01

    Recent decades have witnessed increasing institutionalization of mediation support through the establishment of mediation support structures (MSS) within foreign ministries and secretariats of multilateral organizations. This study sheds light on this trend and aims to better understand the emergence, design and development of different MSS. This study analyzes six MSS, namely those established in the United Nations (UN), the Organization for Security and Co-operation in Europe (OSCE), the Eu...

  16. Understanding nuclear issues

    International Nuclear Information System (INIS)

    Marx, G.

    1999-01-01

    In our days technological progress for the benefit of society is slowed down by the fact that common citizens (opinion-forming media reporters, journalists, furthermore elected decision-makers) are underinformed about basic numerical facts concerning harms and benefits of high technology. Here a comparative risk study is presented about smoking, ozone hole, global warming, and ionizing radiation. This approach has turned out to be successful in educating the youth in Hungary; because school-going teenagers do understand numbers. (author)

  17. Image Understanding Research

    Science.gov (United States)

    1980-03-31

    Numerlues en Sciences Physiques et Economiques , Collection Methode Mathematiques de l’Informatique, Dunod, 1976. 47 26. P. Saint-Pierre, "Etude Theorique et...overlap since adjacent linear features are being presented. References 1. S. Rubin, "The ARGOS Image Understanding System," Ph.D. thesis, Computer Science ...Techniques," TR 480, Computer Science Center, University of Maryland, September i979. 5. Davis, Larry S. and Azriel Rosenfeld, "Hierarchical Relaxation for

  18. Understanding advanced statistical methods

    CERN Document Server

    Westfall, Peter

    2013-01-01

    Introduction: Probability, Statistics, and ScienceReality, Nature, Science, and ModelsStatistical Processes: Nature, Design and Measurement, and DataModelsDeterministic ModelsVariabilityParametersPurely Probabilistic Statistical ModelsStatistical Models with Both Deterministic and Probabilistic ComponentsStatistical InferenceGood and Bad ModelsUses of Probability ModelsRandom Variables and Their Probability DistributionsIntroductionTypes of Random Variables: Nominal, Ordinal, and ContinuousDiscrete Probability Distribution FunctionsContinuous Probability Distribution FunctionsSome Calculus-Derivatives and Least SquaresMore Calculus-Integrals and Cumulative Distribution FunctionsProbability Calculation and SimulationIntroductionAnalytic Calculations, Discrete and Continuous CasesSimulation-Based ApproximationGenerating Random NumbersIdentifying DistributionsIntroductionIdentifying Distributions from Theory AloneUsing Data: Estimating Distributions via the HistogramQuantiles: Theoretical and Data-Based Estimate...

  19. Regional differential effects of the novel histamine H3 receptor antagonist 6-[(3-cyclobutyl-2,3,4,5-tetrahydro-1H-3-benzazepin-7-yl)oxy]-N-methyl-3-pyridinecarboxamide hydrochloride (GSK189254) on histamine release in the central nervous system of freely moving rats.

    Science.gov (United States)

    Giannoni, Patrizia; Medhurst, Andrew D; Passani, Maria Beatrice; Giovannini, Maria Grazia; Ballini, Chiara; Corte, Laura Della; Blandina, Patrizio

    2010-01-01

    After oral administration, the nonimidazole histamine H(3) receptor antagonist, 6-[(3-cyclobutyl-2,3,4,5-tetrahydro-1H-3-benzazepin-7-yl)oxy]-N-methyl-3-pyridinecarboxamide hydrochloride (GSK189254), increased histamine release from the tuberomammillary nucleus, where all histaminergic somata are localized, and from where their axons project to the entire brain. To further understand functional histaminergic circuitry in the brain, dual-probe microdialysis was used to pharmacologically block H(3) receptors in the tuberomammillary nucleus, and monitor histamine release in projection areas. Perfusion of the tuberomammillary nucleus with GSK189254 increased histamine release from the tuberomammillary nucleus, nucleus basalis magnocellularis, and cortex, but not from the striatum or nucleus accumbens. Cortical acetylcholine (ACh) release was also increased, but striatal dopamine release was not affected. When administered locally, GSK189254 increased histamine release from the nucleus basalis magnocellularis, but not from the striatum. Thus, defined by their sensitivity to GSK189254, histaminergic neurons establish distinct pathways according to their terminal projections, and can differentially modulate neurotransmitter release in a brain region-specific manner. Consistent with its effects on cortical ACh release, systemic administration of GSK189254 antagonized the amnesic effects of scopolamine in the rat object recognition test, a cognition paradigm with important cortical components.

  20. In vivo imaging of the cyclic changes in cross-sectional shape of the ventricular segment of pulsating embryonic chick hearts at stages 14 to 17: a contribution to the understanding of the ontogenesis of cardiac pumping function.

    Science.gov (United States)

    Männer, Jörg; Thrane, Lars; Norozi, Kambiz; Yelbuz, T Mesud

    2009-12-01

    The cardiac cycle-related deformations of tubular embryonic hearts were traditionally described as concentric narrowing and widening of a tube of circular cross-section. Using optical coherence tomography (OCT), we have recently shown that, during the cardiac cycle, only the myocardial tube undergoes concentric narrowing and widening while the endocardial tube undergoes eccentric narrowing and widening, having an elliptic cross-section at end-diastole and a slit-shaped cross-section at end-systole. Due to technical limitations, these analyses were confined to early stages of ventricular development (chick embryos, stages 10-13). Using a modified OCT-system, we now document, for the first time, the cyclic changes in cross-sectional shape of beating embryonic ventricles at stages 14 to 17. We show that during these stages (1) a large area of diminished cardiac jelly appears at the outer curvature of the ventricular region associated with formation of endocardial pouches; (2) the ventricular endocardial lumen acquires a bell-shaped cross-section at end-diastole and becomes compressed like a fireplace bellows during systole; (3) the contracting portions of the embryonic ventricles display stretching along its baso-apical axis at end-systole. The functional significance of our data is discussed with respect to early cardiac pumping function. (c) 2009 Wiley-Liss, Inc.

  1. Copper (II) addition to accelerate lactic acid production from co-fermentation of food waste and waste activated sludge: Understanding of the corresponding metabolisms, microbial community and predictive functional profiling.

    Science.gov (United States)

    Ye, Tingting; Li, Xiang; Zhang, Ting; Su, Yinglong; Zhang, Wenjuan; Li, Jun; Gan, Yanfei; Zhang, Ai; Liu, Yanan; Xue, Gang

    2018-03-20

    Bio-refinery of food waste and waste activated sludge to high value-added chemicals, such as lactic acid, has attracted particular interest in recent years. In this paper, the effect of copper (II) dosing to the organic waste fermentation system on lactic acid production was evaluated, which proved to be a promising method to stimulate high yield of lactic acid (77.0% higher than blank) at dosage of 15 μM-Cu 2+ /g VSS. As mechanism study suggested, copper addition enhanced the activity of α-glycosidase and glycolysis, which increased the substrate for subsequent acidification; whereas, the high dosage (70 μM-Cu 2+ /g VSS) inhibited the conversion of lactic acid to VFA, thus stabilized lactic acid concentration. Microbial community study revealed that small amount of copper (II) at 15 μM/g VSS resulted in the proliferation of Lactobacillus to 82.6%, which mainly produced lactic acid. Finally, the variation of functional capabilities implied that the proposed homeostatic system II was activated at relatively low concentration of copper. Meanwhile, membrane transport function and carbohydrate metabolism were also strengthened. This study provides insights into the effect of copper (II) on the enhancement of lactic acid production from co-fermentation of food waste and waste activated sludge. Copyright © 2018 Elsevier Ltd. All rights reserved.

  2. Understanding Interest Rate Volatility

    DEFF Research Database (Denmark)

    Volker, Desi

    with and without stochastic volatility to capture the main stylized features of U.S. interest rates. The third essay, \\Variance Risk Premia in the Interest Rate Swap Market", investigates the time-series and cross-sectional properties of the compensation demanded for holding interest rate variance risk. The essays...... are self-contained and can be read independently. There is however a common thread in the themes covered as all essays focus on the understanding of interest rate volatility, its time-variation and main determinants....

  3. Understanding Ebola Virus Transmission

    Directory of Open Access Journals (Sweden)

    Seth Judson

    2015-02-01

    Full Text Available An unprecedented number of Ebola virus infections among healthcare workers and patients have raised questions about our understanding of Ebola virus transmission. Here, we explore different routes of Ebola virus transmission between people, summarizing the known epidemiological and experimental data. From this data, we expose important gaps in Ebola virus research pertinent to outbreak situations. We further propose experiments and methods of data collection that will enable scientists to fill these voids in our knowledge about the transmission of Ebola virus.

  4. Understanding Computational Bayesian Statistics

    CERN Document Server

    Bolstad, William M

    2011-01-01

    A hands-on introduction to computational statistics from a Bayesian point of view Providing a solid grounding in statistics while uniquely covering the topics from a Bayesian perspective, Understanding Computational Bayesian Statistics successfully guides readers through this new, cutting-edge approach. With its hands-on treatment of the topic, the book shows how samples can be drawn from the posterior distribution when the formula giving its shape is all that is known, and how Bayesian inferences can be based on these samples from the posterior. These ideas are illustrated on common statistic

  5. Understanding Homicide-Suicide.

    Science.gov (United States)

    Knoll, James L

    2016-12-01

    Homicide-suicide is the phenomenon in which an individual kills 1 or more people and commits suicide. Research on homicide-suicide has been hampered by a lack of an accepted classification scheme and reliance on media reports. Mass murder-suicide is gaining increasing attention particularly in the United States. This article reviews the research and literature on homicide-suicide, proposing a standard classification scheme. Preventive methods are discussed and sociocultural factors explored. For a more accurate and complete understanding of homicide-suicide, it is argued that future research should use the full psychological autopsy approach, to include collateral interviews. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. Understanding quantum phase transitions

    CERN Document Server

    Carr, Lincoln

    2010-01-01

    Quantum phase transitions (QPTs) offer wonderful examples of the radical macroscopic effects inherent in quantum physics: phase changes between different forms of matter driven by quantum rather than thermal fluctuations, typically at very low temperatures. QPTs provide new insight into outstanding problems such as high-temperature superconductivity and display fundamental aspects of quantum theory, such as strong correlations and entanglement. Over the last two decades, our understanding of QPTs has increased tremendously due to a plethora of experimental examples, powerful new numerical meth

  7. Understanding MARC: Another Look

    Directory of Open Access Journals (Sweden)

    Roy Chang

    1989-12-01

    Full Text Available 無MARC format has been widely used and discussed in our profession. However, there appear to have a wide spread misunderstanding of its real structure and attributes. This article discuss the needs for us to understand it a little more. Also, it presents the general misconceptions about MARC, the compatibility of MARC, the structure of MARC, standardization and - data communication, and some major issues related to MARC format. In this library automation age, MARC is a key element in library services, and it deserves us to take another look.

  8. Understanding Teen UX

    DEFF Research Database (Denmark)

    Fitton, Daniel; Iversen, Ole Sejer; Bell, Beth

    2014-01-01

    needs to be understood about this population, from a UX perspective. The theme of this workshop is Building a Bridge to the Future and the aim is to gather together academics and UX practitioners, interested in teen users specifically, in order to discuss experiences, understandings, insights...... and methods that we can use to comprehend teen UX now and explore how this may lead to the creation of better interactive products in the future. The workshop will also foster new collaborations, and define new research agendas to grow the research and literature in this area....

  9. Understanding DSGE models

    CERN Document Server

    Costa Junior, Celso Jose

    2016-01-01

    While the theoretical development of DSGE models is not overly difficult to understand, practical application remains somewhat complex. The literature on this subject has some significant obscure points. This book can be thought of, firstly, as a tool to overcome initial hurdles with this type of modeling. Secondly, by showcasing concrete applications, it aims to persuade incipient researchers to work with this methodology. In principle, this is not a book on macroeconomics in itself, but on tools used in the construction of this sort of models. It strives to present this technique in a detail

  10. Understanding the function and performance of carbon-enhanced lead-acid batteries : milestone report for the DOE energy storage systems program (FY11 Quarter 3: April through June 2011).

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Summer Rhodes; Shane, Rodney (East Penn Manufacturing, Lyon Station, PA); Enos, David George

    2011-09-01

    This report describes the status of research being performed under CRADA No. SC10/01771.00 (Lead/Carbon Functionality in VRLA Batteries) between Sandia National Laboratories and East Penn Manufacturing, conducted for the U.S. Department of Energy's Energy Storage Systems Program. The Quarter 3 Milestone was completed on time. The milestone entails an ex situ analysis of a control as well as three carbon-containing negative plates in the raw, as cast form as well as after formation. The morphology, porosity, and porosity distribution within each plate was evaluated. In addition, baseline electrochemical measurements were performed on each battery to establish their initial performance. These measurements included capacity, internal resistance, and float current. The results obtained for the electrochemical testing were in agreement with previous evaluations performed at East Penn manufacturing. Cycling on a subset of the received East Penn cells containing different carbons (and a control) has been initiated.

  11. Understanding the site selectivity in small-sized neutral and charged Al(n) (4 ≤ N ≤ 7) clusters using density functional theory based reactivity descriptors: a validation study on water molecule adsorption.

    Science.gov (United States)

    Das, Susanta; Pal, Sourav; Krishnamurty, Sailaja

    2013-09-12

    Aluminum clusters are now technologically important due to their high catalytic activity. Our present study on the small-sized aluminum clusters applies density functional theory (DFT)-based reactivity descriptors to identify potential sites for adsorption and eventual chemical reaction. Depending on symmetry, susceptibility of various type of reactive sites within a cluster toward an impending electrophilic and/or nucleophilic attack is predicted using the reactivity descriptors. In addition, the study devises general rules as to how the size, shape, and charge of the cluster influences the number of available sites for an electrophilic and/or nucleophilic attack. The predictions by reactivity descriptors are validated by performing an explicit adsorption of water molecule on Al clusters with four atoms. The adsorption studies demonstrate that the most stable water-cluster complex is obtained when the molecule is adsorbed through an oxygen atom on the site with the highest relative electrophilicity.

  12. Understanding Callisto's Atmosphere

    Science.gov (United States)

    Spencer, John

    2016-10-01

    We plan to address first-order questions about the nature and origin of the mysterious atmosphere of Callisto, including its composition, longitudinal distribution, formation, and support mechanisms. This investigation is made possible by the remarkable sensitivity of the COS instrument, which has recently detected faint 1304 A and 1356 A O I emission from Callisto's leading / Jupiter-facing quadrant. The emission is probably due to dissociation of O2 molecules in Callisto's atmosphere by photo-electrons, and resonant scattering from an extended atomic O corona. We suspect, from Galileo ionospheric data, that the atmosphere may be much denser, and brighter in emission, on the trailing hemisphere, as expected for a sputter-generated atmosphere, and propose to test the sputter generation hypothesis with 4-orbit COS integrations on the leading and trailing hemispheres. If the trailing side emissions are indeed brighter, the improved SNR there will also allow much improved determination of atmospheric and coronal composition and optical depth. The observations will set the stage for, and aid in planning of, the extensive observations of Callisto's environment planned for the JUICE mission. Because Callisto's atmospheric oxygen emissions are indirectly illuminated by sunlight, which is uniform and quantifiable, it is much easier to understand atmospheric spatial distribution, and thus origin, than on Europa and Ganymede were emissions depend on magnetospheric excitation which is spatially variable and poorly understood. Callisto's atmosphere thus provides a unique chance to better understand the oxygen atmospheres of all the icy Galilean moons.

  13. Understanding scaling laws

    International Nuclear Information System (INIS)

    Lysenko, W.P.

    1986-01-01

    Accelerator scaling laws how they can be generated, and how they are used are discussed. A scaling law is a relation between machine parameters and beam parameters. An alternative point of view is that a scaling law is an imposed relation between the equations of motion and the initial conditions. The relation between the parameters is obtained by requiring the beam to be matched. (A beam is said to be matched if the phase-space distribution function is a function of single-particle invariants of the motion.) Because of this restriction, the number of independent parameters describing the system is reduced. Using simple models for bunched- and unbunched-beam situations. Scaling laws are shown to determine the general behavior of beams in accelerators. Such knowledge is useful in design studies for new machines such as high-brightness linacs. The simple model presented shows much of the same behavior as a more detailed RFQ model

  14. Understanding Life After Stroke

    OpenAIRE

    Hjelmblink, Finn

    2008-01-01

    Stroke is an acute, neurological dysfunction of vascular origin with sudden occurrence and it influences physical, cognitive and psychological functions. Initial treatment aims at eliminating or reducing the brain damage. Soon, however, the influence of the stroke on the entire life of stroke survivors has to be considered. This thesis explores the meaning of life after stroke to 19 elderly stroke survivors during the first year post stroke. Survivors were interviewed twice and the interviews...

  15. Hierarchical Multisensor Image Understanding.

    Science.gov (United States)

    1984-07-01

    for all linear shifts in a 6-0 hyperspace . If the resulting 6-0 correlation function 0 exceeds threshold somewhere, then recognition is achieved. The...position and spatial frequency relations in the receptive fields of simple cells in the visual cortex, I iol. Xhrn*Zci 43, 187-198 (1982). 33. S...arcelja, Mathematical description of the responses of simple cortical cells , ,.U %r,, Am, 70, 1297-1300 (1980). 34. W. Wigner, On the quantum correction

  16. Understanding engineering mathematics

    CERN Document Server

    Cox, Bill

    2001-01-01

    * Unique interactive style enables students to diagnose their strengths and weaknesses and focus their efforts where needed* Ideal for self-study and tutorial work, building from an initially supportive approach to the development of independent learning skills * Free website includes solutions to all exercises, additional topics and applications, guide to learning mathematics, and practice materialStudents today enter engineering courses with a wide range of mathematical skills, due to the many different pre-university qualifications studied. Bill Cox''s aim is for students to gain a thorough understanding of the maths they are studying, by first strengthening their background in the essentials of each topic. His approach allows a unique self-paced study style, in which students Review their strengths and weaknesses through self-administered diagnostic tests, then focus on Revision where they need it, to finally Reinforce the skills required.The book is structured around a highly successful ''transition'' ma...

  17. From understanding to participation

    DEFF Research Database (Denmark)

    Raudaskoski, Pirkko Liisa

    2013-01-01

    The paper presents some methodological considerations around the topic of the AFinLA 2012 Autumn Symposium: Multimodal discourses of participation. The aim is to shed theoretical and analytical light on embodied participation in material settings. The research is placed in a relational perspective...... in which entities (for example, the world, culture, society, organization and identities) emerge through entangled, layered practices in concrete circumstances. Understanding is not treated as a philosophical puzzle or as a purely linguistic phenomenon. Rather, it is conceptualized as an embodied......, multimodal process in which language together with bodily senses (vision, hearing, touch, smell and taste) and a sense of place contribute to a phenomenon being recognized (as shared). Participation can result in inclusion or exclusion, a claim which is discussed with the help of a pilot study from...

  18. Understanding land administration systems

    DEFF Research Database (Denmark)

    P. Williamson, Ian; Enemark, Stig; Wallace, Judy

    2008-01-01

    This paper introduces basic land administration theory and highlights four key concepts that are fundamental to understanding modern land administration systems - firstly the land management paradigm and its influence on the land administration framework, secondly the role that the cadastre plays...... in contributing to sustainable development, thirdly the changing nature of ownership and the role of land markets, and lastly a land management vision that promotes land administration in support of sustainable development and spatial enablement of society. We present here the first part of the paper. The second...... part focuses on the changing  role of ownership and the role of land markets, and a land management vision will be published in November issue of Coordinates. Udgivelsesdato: Oktober...

  19. Understanding medical symptoms

    DEFF Research Database (Denmark)

    Malterud, Kirsti; Guassora, Ann Dorrit Kristiane; Graungaard, Anette Hauskov

    2015-01-01

    perspectives deal with how symptom perception occurs when any kind of altered balance brings forward a bodily attention. Corporeality is brought to explicit awareness and perceived as sensations. Jesper Hoffmeyer’s biosemiotic perspectives provide access to how signs are interpreted to attribute meaning......The aim of this article is to present a conceptual review and analysis of symptom understanding. Subjective bodily sensations occur abundantly in the normal population and dialogues about symptoms take place in a broad range of contexts, not only in the doctor’s office. Our review of symptom...... is a social and relational phenomenon of containment, and regulating the situation where the symptoms originate implies adjusting containment. Discourse analysis, as presented by Jonathan Potter and Margaret Wetherell, provides a tool to notice the subtle ways in which language orders perceptions and how...

  20. Understanding philosophical animal

    Directory of Open Access Journals (Sweden)

    Popović Una

    2010-01-01

    Full Text Available In this paper, inspired by the Predrag Krstić's book Philosophical Animal author is trying to find hers way through a broad and complex web of philosophies and roles that different animals play in them. The main question is how to understand philosophy itself in a present day context, which philosophy is supposed to think and rethink through. Animals as presented in concepts, more precisely philosophical contexts, open one interesting and innovative way to deal with this question, balancing between tradition of philosophy and its presence, structure of philosophical arguments and questioning of language of philosophy, abstract and individual. In this frame philosopher as the true philosophical animal is revealed as the main symbol that requires analysis in his philosophical strategies.

  1. Towards better process understanding

    DEFF Research Database (Denmark)

    Matero, Sanni Elina; van der Berg, Franciscus Winfried J; Poutiainen, Sami

    2013-01-01

    The manufacturing of tablets involves many unit operations that possess multivariate and complex characteristics. The interactions between the material characteristics and process related variation are presently not comprehensively analyzed due to univariate detection methods. As a consequence......, current best practice to control a typical process is to not allow process-related factors to vary i.e. lock the production parameters. The problem related to the lack of sufficient process understanding is still there: the variation within process and material properties is an intrinsic feature...... and cannot be compensated for with constant process parameters. Instead, a more comprehensive approach based on the use of multivariate tools for investigating processes should be applied. In the pharmaceutical field these methods are referred to as Process Analytical Technology (PAT) tools that aim...

  2. Understanding climatic change

    International Nuclear Information System (INIS)

    Fellous, J.L.; Gautier, C.; Andre, J.C.; Balstad, R.; Boucher, O.; Brasseur, G.; Chahine, M.T.; Chanin, M.L.; Ciais, P.; Corell, W.; Duplessy, J.C.; Hourcade, J.C.; Jouzel, J.; Kaufman, Y.J.; Laval, K.; Le Treut, H.; Minster, J.F.; Moore, B. III; Morel, P.; Rasool, S.I.; Remy, F.; Smith, R.C.; Somerville, R.C.J.; Wood, E.F.; Wood, H.; Wunsch, C.

    2007-01-01

    Climatic change is gaining ground and with no doubt is stimulated by human activities. It is therefore urgent to better understand its nature, importance and potential impacts. The chapters of this book have been written by US and French experts of the global warming question. After a description of the Intergovernmental Panel on Climate Change (IPCC, GIEC in French) consensus, they present the past and present researches on each of the main component of the climate system, on the question of climatic change impacts and on the possible answers. The conclusion summarizes the results of each chapter. Content: presentation of the IPCC; greenhouse effect, radiation balance and clouds; atmospheric aerosols and climatic change; global water cycle and climate; influence of climatic change on the continental hydrologic cycle; ocean and climate; ice and climate; global carbon cycle; about some impacts of climatic change on Europe and the Atlantic Ocean; interaction between atmospheric chemistry and climate; climate and society, the human dimension. (J.S.)

  3. Understanding person perception.

    Science.gov (United States)

    Young, Andrew W; Bruce, Vicki

    2011-11-01

    Bruce and Young's (1986) theoretical framework was actually a synthesis of ideas contributed by several people. Some of its insights have stood the test of time - especially the importance of using converging evidence from as wide a range of methods of enquiry as possible, and an emphasis on understanding the demands that are made by particular face perception tasks. But there were also areas where Bruce and Young failed to obey their own edicts (emotion recognition), and some topics they simply omitted (gaze perception). We discuss these, and then look at how the field has been transformed by computing developments, finishing with a few thoughts about where things may go over the next few (25?) years. ©2011 The British Psychological Society.

  4. Understanding social motor coordination.

    Science.gov (United States)

    Schmidt, R C; Fitzpatrick, Paula; Caron, Robert; Mergeche, Joanna

    2011-10-01

    Recently there has been much interest in social coordination of motor movements, or as it is referred to by some researchers, joint action. This paper reviews the cognitive perspective's common coding/mirror neuron theory of joint action, describes some of its limitations and then presents the behavioral dynamics perspective as an alternative way of understanding social motor coordination. In particular, behavioral dynamics' ability to explain the temporal coordination of interacting individuals is detailed. Two experiments are then described that demonstrate how dynamical processes of synchronization are apparent in the coordination underlying everyday joint actions such as martial art exercises, hand-clapping games, and conversations. The import of this evidence is that emergent dynamic patterns such as synchronization are the behavioral order that any neural substrate supporting joint action (e.g., mirror systems) would have to sustain. Copyright © 2010 Elsevier B.V. All rights reserved.

  5. Understanding traditional African healing.

    Science.gov (United States)

    Mokgobi, M G

    2014-09-01

    Traditional African healing has been in existence for many centuries yet many people still seem not to understand how it relates to God and religion/spirituality. Some people seem to believe that traditional healers worship the ancestors and not God. It is therefore the aim of this paper to clarify this relationship by discussing a chain of communication between the worshipers and the Almighty God. Other aspects of traditional healing namely types of traditional healers, training of traditional healers as well as the role of traditional healers in their communities are discussed. In conclusion, the services of traditional healers go far beyond the uses of herbs for physical illnesses. Traditional healers serve many roles which include but not limited to custodians of the traditional African religion and customs, educators about culture, counselors, social workers and psychologists.

  6. Understanding the function and performance of carbon-enhanced lead-acid batteries : milestone report for the DOE Energy Storage Systems program (FY11 Quarter 2: January through March 2011).

    Energy Technology Data Exchange (ETDEWEB)

    Shane, R. (East Penn Manufacturing, Lyon Station, PA); Enos, David George; Hund, Thomas D.

    2011-05-01

    This report describes the status of research being performed under CRADA No. SC10/01771.00 (Lead/Carbon Functionality in VRLA Batteries) between Sandia National Laboratories and East Penn Manufacturing, conducted for the U.S. Department of Energy's Energy Storage Systems Program. The Quarter 2 Milestone was completed on time. The milestone entails an ex situ analysis of the four carbons that have been added to the negative active material of valve-regulated lead-acid (VRLA) batteries for the purposes of this study. The four carbons selected for this study were a graphitic carbon, a carbon black, an activated carbon, and acetylene black. The morphology, crystallinity, and impurity contents of each of the four carbons were analyzed; results were consistent with previous data. Cycling on a subset of the received East Penn cells containing different carbons (and a control) has been initiated. Carbon has been explored as an addition to lead-acid battery electrodes in a number of ways. Perhaps the most notable to date has been the hybrid 'Ultrabattery' developed by CSIRO where an asymmetric carbon-based electrochemical capacitor is combined with a lead-acid battery into a single cell, dramatically improving high-rate partial-state-of-charge (HRPSoC) operation. As illustrated below, the 'Ultrabattery' is a hybrid device constructed using a traditional lead-acid battery positive plate (i.e., PbO{sub 2}) and a negative electrode consisting of a carbon electrode in parallel with a lead-acid negative plate. This device exhibits a dramatically improved cycle life over traditional VRLA batteries, as well as increased charge power and charge acceptance. The 'Ultrabattery' has been produced successfully by both The Furukawa Battery Co. and East Penn Manufacturing. An example illustrating the dramatic improvement in cycle life of the Ultrabattery over a conventional VRLA battery is shown.

  7. Understanding customer experience.

    Science.gov (United States)

    Meyer, Christopher; Schwager, Andre

    2007-02-01

    Anyone who has signed up for cell phone service, attempted to claim a rebate, or navigated a call center has probably suffered from a company's apparent indifference to what should be its first concern: the customer experiences that culminate in either satisfaction or disappointment and defection. Customer experience is the subjective response customers have to direct or indirect contact with a company. It encompasses every aspect of an offering: customer care, advertising, packaging, features, ease of use, reliability. Customer experience is shaped by customers' expectations, which largely reflect previous experiences. Few CEOs would argue against the significance of customer experience or against measuring and analyzing it. But many don't appreciate how those activities differ from CRM or just how illuminating the data can be. For instance, the majority of the companies in a recent survey believed they have been providing "superior" experiences to customers, but most customers disagreed. The authors describe a customer experience management (CEM) process that involves three kinds of monitoring: past patterns (evaluating completed transactions), present patterns (tracking current relationships), and potential patterns (conducting inquiries in the hope of unveiling future opportunities). Data are collected at or about touch points through such methods as surveys, interviews, focus groups, and online forums. Companies need to involve every function in the effort, not just a single customer-facing group. The authors go on to illustrate how a cross-functional CEM system is created. With such a system, companies can discover which customers are prospects for growth and which require immediate intervention.

  8. Tools for Understanding Identity

    Energy Technology Data Exchange (ETDEWEB)

    Creese, Sadie; Gibson-Robinson, Thomas; Goldsmith, Michael; Hodges, Duncan; Kim, Dee DH; Love, Oriana J.; Nurse, Jason R.; Pike, William A.; Scholtz, Jean

    2013-12-28

    Identity attribution and enrichment is critical to many aspects of law-enforcement and intelligence gathering; this identity typically spans a number of domains in the natural-world such as biographic information (factual information – e.g. names, addresses), biometric information (e.g. fingerprints) and psychological information. In addition to these natural-world projections of identity, identity elements are projected in the cyber-world. Conversely, undesirable elements may use similar techniques to target individuals for spear-phishing attacks (or worse), and potential targets or their organizations may want to determine how to minimize the attack surface exposed. Our research has been exploring the construction of a mathematical model for identity that supports such holistic identities. The model captures the ways in which an identity is constructed through a combination of data elements (e.g. a username on a forum, an address, a telephone number). Some of these elements may allow new characteristics to be inferred, hence enriching the holistic view of the identity. An example use-case would be the inference of real names from usernames, the ‘path’ created by inferring new elements of identity is highlighted in the ‘critical information’ panel. Individual attribution exercises can be understood as paths through a number of elements. Intuitively the entire realizable ‘capability’ can be modeled as a directed graph, where the elements are nodes and the inferences are represented by links connecting one or more antecedents with a conclusion. The model can be operationalized with two levels of tool support described in this paper, the first is a working prototype, the second is expected to reach prototype by July 2013: Understanding the Model The tool allows a user to easily determine, given a particular set of inferences and attributes, which elements or inferences are of most value to an investigator (or an attacker). The tool is also able to take

  9. Do mirror neurons subserve action understanding?

    Science.gov (United States)

    Hickok, Gregory

    2013-04-12

    Mirror neurons were once widely believed to support action understanding via motor simulation of the observed actions. Recent evidence regarding the functional properties of mirror neurons in monkeys as well as much neuropsychological evidence in humans has shown that this is not the case. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  10. Do Mirror Neurons Subserve Action Understanding?

    OpenAIRE

    Hickok, Gregory

    2012-01-01

    Mirror neurons were once widely believed to support action understanding via motor simulation of the observed actions. Recent evidence regarding the functional properties of mirror neurons in monkeys as well as much neuropsychological evidence in humans has shown that this is not the case

  11. Awareness, knowledge, understanding and readiness to adopt

    African Journals Online (AJOL)

    user

    ISSN 0378-5254 Journal of Family Ecology and Consumer Sciences, Vol 40, 2012. AWARENESS, KNOWLEDGE, UNDERSTANDING .... market for functional foods in a global online survey by AC Nielsen in 2005 (Nielsen, 2005:9). Hawkins et al ...... Consumer reactions to foods with nutrition and health claims. Agro-.

  12. Understanding and controlling the enteric nervous system

    NARCIS (Netherlands)

    Boeckxstaens, G. E.

    2002-01-01

    The enteric nervous system or the `Little Brain' of the gut controls gastrointestinal motility and secretion, and is involved in visceral sensation. In this chapter, new developments in understanding the function of the enteric nervous system are described. In particular, the interaction of this

  13. Ancestral trees for modeling stem cell lineages genetically rather than functionally: understanding mutation accumulation and distinguishing the restrictive cancer stem cell propagation theory and the unrestricted cell propagation theory of human tumorigenesis.

    Science.gov (United States)

    Shibata, Darryl K; Kern, Scott E

    2008-01-01

    Cancer stem cells either could be rare or common in tumors, constituting the major distinction between the two fundamentally opposed theoretical models of tumor progression: A newer and restrictive stem cell propagation model, in which the stem cells are a small and special minority of the tumor cells, and a standard older model, an unrestricted cell proliferation theory, in which many or most tumor cells are capable of indefinite generations of cell division. Stem cells of tumors are difficult to quantitate using functional assays, and the validity of the most common assays is seriously questioned. Nonetheless, stem cells are an essential component of any tumorigenesis model. Alternative approaches to studying tumor stem cells should be explored. Cell populations can be conceived of as having a genealogy, a relationship of cells to their ancestral lineage, from the zygote to the adult cells or neoplasms. Models using ancestral trees thus offer an anatomic and genetic means to "observe" stem cells independent of artificial conditions. Ancestral trees broaden our attention backward along a lineage, to the zygote stage, and thereby add insight into how the mutations of tumors accumulate. It is possible that a large fraction of mutations in a tumor originate from normal, endogenous, replication errors (nearly all being passenger mutations) occurring prior to the emergence of the first transformed cell. Trees can be constructed from experimental measurements - molecular clocks - of real human tissues and tumors. Detailed analysis of single-cell methylation patterns, heritable yet slightly plastic, now can provide this information in the necessary depth. Trees based on observations of molecular clocks may help us to distinguish between competing theories regarding the proliferative properties among cells of actual human tumors, to observe subtle and difficult phenomena such as the extinction of stem lineages, and to address the origins and rates of mutations in various

  14. Towards understanding oral health.

    Science.gov (United States)

    Zaura, Egija; ten Cate, Jacob M

    2015-01-01

    During the last century, dental research has focused on unraveling the mechanisms behind various oral pathologies, while oral health was typically described as the mere absence of oral diseases. The term 'oral microbial homeostasis' is used to describe the capacity of the oral ecosystem to maintain microbial community stability in health. However, the oral ecosystem itself is not stable: throughout life an individual undergoes multiple physiological changes while progressing through infancy, childhood, adolescence, adulthood and old age. Recent discussions on the definition of general health have led to the proposal that health is the ability of the individual to adapt to physiological changes, a condition known as allostasis. In this paper the allostasis principle is applied to the oral ecosystem. The multidimensionality of the host factors contributing to allostasis in the oral cavity is illustrated with an example on changes occurring in puberty. The complex phenomenon of oral health and the processes that prevent the ecosystem from collapsing during allostatic changes in the entire body are far from being understood. As yet individual components (e.g. hard tissues, microbiome, saliva, host response) have been investigated, while only by consolidating these and assessing their multidimensional interactions should we be able to obtain a comprehensive understanding of the ecosystem, which in turn could serve to develop rational schemes to maintain health. Adapting such a 'system approach' comes with major practical challenges for the entire research field and will require vast resources and large-scale multidisciplinary collaborations. 2015 S. Karger AG, Basel

  15. Understanding anatomical terms.

    Science.gov (United States)

    Mehta, L A; Natrajan, M; Kothari, M L

    1996-01-01

    Words are our masters and words are our slaves, all depending on how we use them. The whole of medical science owes its origin to Greco-Roman culture and is replete with terms whose high sound is not necessarily accompanied by sound meaning. This is even more the case in the initial, pre-clinical years. Anatomical terminology seems bewildering to the initiate; and maybe that is a reason why love of anatomy as a subject does not always spill over through later years. Employing certain classifications of the origin of the anatomical terms, we have prepared an anthology that we hope will ease the student's task and also heighten the student's appreciation of the new terms. This centers on revealing the Kiplingian "how, why, when, where, what, and who" of a given term. This presentation should empower students to independently formulate a wide network of correlations once they understand a particular term. The article thus hopes to stimulate students' analytic and synthetic faculties as well. A small effort can reap large rewards in terms of enjoyment of the study of anatomy and the related subjects of histology, embryology, and genetics. It is helpful to teachers and students alike. This exercise in semantics and etymology does not demand of the student or his teacher any background in linguistics, grammar, Greek, Latin, Sanskrit, anatomy, or medicine.

  16. Understanding Autism in Schizophrenia

    Directory of Open Access Journals (Sweden)

    Arnaldo Ballerini

    2012-01-01

    Full Text Available Detachment from external reality, distancing from others, closure into a sort of virtual hermitage, and prevalence of inner fantasies, are the descriptive aspects of autism. However, from an anthropological-phenomenological point of view, in schizophrenia, the autistic mode of life can arise from a person’s being confronted with a pathological crisis in the obviousness of the intersubjective world, essentially a crisis in the intersubjective foundation of human presence. The “condition of possibility” of the autistic way of being is the deficiency of the operation that phenomenology call empathetic-intuitive constitution of the Other, an Other which is the naturalness of evidence of being a subject like me. The theme of the Other, of intersubjectivity, has become so central in the psychopathological analysis of schizophrenic disorders because the modifications of interhuman encounter cannot be seen as the secondary consequences of symptoms but constitute the fundamental disorder of schizophrenic alienation. Revision of the concept of autism from the original definition, centered on the prevalence of inner fantasies, leads to the profound change with the vision of autism as “loss” and “void.” I call attention to possibility of phenomenological research to understand autistic world starting from this “void.”

  17. Understanding autism in schizophrenia.

    Science.gov (United States)

    Ballerini, Arnaldo

    2012-01-01

    Detachment from external reality, distancing from others, closure into a sort of virtual hermitage, and prevalence of inner fantasies, are the descriptive aspects of autism. However, from an anthropological-phenomenological point of view, in schizophrenia, the autistic mode of life can arise from a person's being confronted with a pathological crisis in the obviousness of the intersubjective world, essentially a crisis in the intersubjective foundation of human presence. The "condition of possibility" of the autistic way of being is the deficiency of the operation that phenomenology call empathetic-intuitive constitution of the Other, an Other which is the naturalness of evidence of being a subject like me. The theme of the Other, of intersubjectivity, has become so central in the psychopathological analysis of schizophrenic disorders because the modifications of interhuman encounter cannot be seen as the secondary consequences of symptoms but constitute the fundamental disorder of schizophrenic alienation. Revision of the concept of autism from the original definition, centered on the prevalence of inner fantasies, leads to the profound change with the vision of autism as "loss" and "void." I call attention to possibility of phenomenological research to understand autistic world starting from this "void."

  18. Understanding the function and performance of carbon-enhanced lead-acid batteries : milestone report for the DOE Energy Storage Systems Program (FY11 Quarter 4: July through September 2011).

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Summer Rhodes; Shane, Rodney (East Penn Manufacturing, Lyon Station, PA); Enos, David George

    2011-10-01

    This report describes the status of research being performed under CRADA No. SC10/01771.00 (Lead/Carbon Functionality in VRLA Batteries) between Sandia National Laboratories and East Penn Manufacturing, conducted for the U.S. Department of Energy's Energy Storage Systems Program. The Quarter 4 Milestone was completed on time. The milestone entails the initiation of high rate, partial state of charge (HRPSoC) cycling of the carbon enhanced batteries. The morphology, porosity, and porosity distribution within the plates after 1k and 10k cycles were documented, illustrating the changes which take place in the early life of the carbon containing batteries, and as the battery approaches failure due to hard sulfation for the control battery. Longer term cycling on a subset of the received East Penn cells containing different carbons (and a control) continues, and will progress into FY12. Carbon has been explored as an addition to lead-acid battery electrodes in a number of ways. Perhaps the most notable to date has been the hybrid 'Ultrabattery' developed by CSIRO where an asymmetric carbon-based electrochemical capacitor is combined with a lead-acid battery into a single cell, dramatically improving high-rate partial-state-of-charge (HRPSoC) operation. As illustrated below, the 'Ultrabattery' is a hybrid device constructed using a traditional lead-acid battery positive plate (i.e., PbO2) and a negative electrode consisting of a carbon electrode in parallel with a lead-acid negative plate. This device exhibits a dramatically improved cycle life over traditional VRLA batteries, as well as increased charge power and charge acceptance. The 'Ultrabattery' has been produced successfully by both The Furukawa Battery Co. and East Penn Manufacturing. An example illustrating the dramatic improvement in cycle life of the Ultrabattery over a conventional VRLA battery is shown in a graph. In addition to the aforementioned hybrid device, carbon has

  19. Understanding Social Media Logic

    Directory of Open Access Journals (Sweden)

    José van Dijck

    2013-08-01

    Full Text Available Over the past decade, social media platforms have penetrated deeply into the mech­anics of everyday life, affecting people's informal interactions, as well as institutional structures and professional routines. Far from being neutral platforms for everyone, social media have changed the conditions and rules of social interaction. In this article, we examine the intricate dynamic between social media platforms, mass media, users, and social institutions by calling attention to social media logic—the norms, strategies, mechanisms, and economies—underpin­ning its dynamics. This logic will be considered in light of what has been identified as mass me­dia logic, which has helped spread the media's powerful discourse outside its institutional boundaries. Theorizing social media logic, we identify four grounding principles—programmabil­ity, popularity, connectivity, and datafication—and argue that these principles become increas­ingly entangled with mass media logic. The logic of social media, rooted in these grounding principles and strategies, is gradually invading all areas of public life. Besides print news and broadcasting, it also affects law and order, social activism, politics, and so forth. Therefore, its sustaining logic and widespread dissemination deserve to be scrutinized in detail in order to better understand its impact in various domains. Concentrating on the tactics and strategies at work in social media logic, we reassess the constellation of power relationships in which social practices unfold, raising questions such as: How does social media logic modify or enhance ex­isting mass media logic? And how is this new media logic exported beyond the boundaries of (social or mass media proper? The underlying principles, tactics, and strategies may be relat­ively simple to identify, but it is much harder to map the complex connections between plat­forms that distribute this logic: users that employ them, technologies that

  20. Understanding individual routing behaviour.

    Science.gov (United States)

    Lima, Antonio; Stanojevic, Rade; Papagiannaki, Dina; Rodriguez, Pablo; González, Marta C

    2016-03-01

    Knowing how individuals move between places is fundamental to advance our understanding of human mobility (González et al. 2008 Nature 453, 779-782. (doi:10.1038/nature06958)), improve our urban infrastructure (Prato 2009 J. Choice Model. 2, 65-100. (doi:10.1016/S1755-5345(13)70005-8)) and drive the development of transportation systems. Current route-choice models that are used in transportation planning are based on the widely accepted assumption that people follow the minimum cost path (Wardrop 1952 Proc. Inst. Civ. Eng. 1, 325-362. (doi:10.1680/ipeds.1952.11362)), despite little empirical support. Fine-grained location traces collected by smart devices give us today an unprecedented opportunity to learn how citizens organize their travel plans into a set of routes, and how similar behaviour patterns emerge among distinct individual choices. Here we study 92 419 anonymized GPS trajectories describing the movement of personal cars over an 18-month period. We group user trips by origin-destination and we find that most drivers use a small number of routes for their routine journeys, and tend to have a preferred route for frequent trips. In contrast to the cost minimization assumption, we also find that a significant fraction of drivers' routes are not optimal. We present a spatial probability distribution that bounds the route selection space within an ellipse, having the origin and the destination as focal points, characterized by high eccentricity independent of the scale. While individual routing choices are not captured by path optimization, their spatial bounds are similar, even for trips performed by distinct individuals and at various scales. These basic discoveries can inform realistic route-choice models that are not based on optimization, having an impact on several applications, such as infrastructure planning, routing recommendation systems and new mobility solutions. © 2016 The Author(s).

  1. Geoparks for understanding geodiversity

    Science.gov (United States)

    Anttila-Muilu, Sirpa

    2015-04-01

    used to enhance the understanding of geodiversity - through different scales.

  2. Understanding "people" people.

    Science.gov (United States)

    Butler, Timothy; Waldroop, James

    2004-06-01

    Nearly all areas of business--not just sales and human resources--call for interpersonal savvy. Relational know-how comprises a greater variety of aptitudes than many executives think. Some people can "talk a dog off a meat truck," as the saying goes. Others are great at resolving interpersonal conflicts. Some have a knack for translating high-level concepts for the masses. And others thrive when they're managing a team. Since people do their best work when it most closely matches their interests, the authors contend, managers can increase productivity by taking into account employees' relational interests and skills when making personnel choices and project assignments. After analyzing psychological tests of more than 7,000 business professionals, the authors have identified four dimensions of relational work: influence, interpersonal facilitation, relational creativity, and team leadership. This article explains each one and offers practical advice to managers--how to build a well-balanced team, for instance, and how to gauge the relational skills of potential employees during interviews. To determine whether a job candidate excels in, say, relational creativity, ask her to describe her favorite advertising campaign, slogan, or image and tell you why she finds it to be so effective. Understanding these four dimensions will help you get optimal performance from your employees, appropriately reward their work, and assist them in setting career goals. It will also help you make better choices when it comes to your own career development. To get started, try the authors' free online assessment tool, which will measure both your orientation toward relational work in general and your interest level in each of its four dimensions.

  3. Understanding the Budget Process

    Directory of Open Access Journals (Sweden)

    Mesut Yalvaç

    2000-03-01

    Full Text Available Many different budgeting techniques can be used in libraries, and some combination of these will be appropriate for almost any individual situation. Li-ne-item, program, performance, formula, variable, and zero-base budgets all have features that may prove beneficial in the preparation of a budget. Budgets also serve a variety of functions, providing for short-term and long-term financial planning as well as for cash management over a period of time. Short-term plans are reflected in the operating budget, while long-term plans are reflected in the capital budget. Since the time when cash is available to an organization does not usually coincide with the time that disbursements must be made, it is also important to carefully plan for the inflow and outflow of funds by means of a cash budget.      During the budget process an organization selects its programs and activities by providing the necessary funding; the library, along with others in the organization, must justify its requests. Because of the cyclical nature of the budget process, it is possible continually to gather information and evaluate alternatives for the next budget period so that the library may achieve its maximum potential for service to its patrons.

  4. Understanding medical ethics.

    Science.gov (United States)

    Little, M

    2000-03-01

    Moral thinking is embedded within cultures, and we use ethics all the time in our dealings with one another. Many functioning communities tend to share some values that reflect a particular view of the importance of human life in quantity and quality. Rights and duties form an interconnected network of obligations that protect the security of individuals and groups. In health care, the motives and virtues of practitioners are important sources of the determination to provide care for the ill within the limits of resource constraints. Ethics and the law have similarities, but also significant differences that may cause tension between the two systems. Health care is morally grounded, and provides a bulwark against the widespread fear of disease and suffering. The way in which health care is delivered depends on both national wealth and community values. Ethical problems can be seen as dilemmas, in which there are conflicting values. Modern ethical thinking in health is complicated by the need to consider the values and interests of many stakeholders--patients, health care workers, families, politicians, administrators, health bureaucrats and many others. There are ways of ethical thinking that take account of these often countervailing interests. No universally 'right' answers can be specified. The mode and the thoroughness of ethical consideration, and the careful consideration of local community values, will help to assure that we make the best possible decisions for the time and place.

  5. Understanding Nitrogen Fixation

    Energy Technology Data Exchange (ETDEWEB)

    Paul J. Chirik

    2012-05-25

    The purpose of our program is to explore fundamental chemistry relevant to the discovery of energy efficient methods for the conversion of atmospheric nitrogen (N{sub 2}) into more value-added nitrogen-containing organic molecules. Such transformations are key for domestic energy security and the reduction of fossil fuel dependencies. With DOE support, we have synthesized families of zirconium and hafnium dinitrogen complexes with elongated and activated N-N bonds that exhibit rich N{sub 2} functionalization chemistry. Having elucidated new methods for N-H bond formation from dihydrogen, C-H bonds and Broensted acids, we have since turned our attention to N-C bond construction. These reactions are particularly important for the synthesis of amines, heterocycles and hydrazines with a range of applications in the fine and commodity chemicals industries and as fuels. One recent highlight was the discovery of a new N{sub 2} cleavage reaction upon addition of carbon monoxide which resulted in the synthesis of an important fertilizer, oxamide, from the diatomics with the two strongest bonds in chemistry. Nitrogen-carbon bonds form the backbone of many important organic molecules, especially those used in the fertilizer and pharamaceutical industries. During the past year, we have continued our work in the synthesis of hydrazines of various substitution patterns, many of which are important precursors for heterocycles. In most instances, the direct functionalization of N{sub 2} offers a more efficient synthetic route than traditional organic methods. In addition, we have also discovered a unique CO-induced N{sub 2} bond cleavage reaction that simultaneously cleaves the N-N bond of the metal dinitrogen compound and assembles new C-C bond and two new N-C bonds. Treatment of the CO-functionalized core with weak Broensted acids liberated oxamide, H{sub 2}NC(O)C(O)NH{sub 2}, an important slow release fertilizer that is of interest to replace urea in many applications. The

  6. Current understanding of the human microbiome

    Energy Technology Data Exchange (ETDEWEB)

    Gilbert, Jack A.; Blaser, Martin J.; Caporaso, J. Gregory; Jansson, Janet K.; Lynch, Susan V.; Knight, Rob

    2018-04-10

    Our understanding of the link between the human microbiome and disease, including obesity, inflammatory bowel disease, arthritis and autism, is rapidly expanding. Improvements in the throughput and accuracy of DNA sequencing of the genomes of microbial communities associated with human samples, complemented by analysis of transcriptomes, proteomes, metabolomes and immunomes, and mechanistic experiments in model systems, have vastly improved our ability to understand the structure and function of the microbiome in both diseased and healthy states. However, many challenges remain. In this Review we focus on studies in humans to describe these challenges, and propose strategies that leverage existing knowledge to move rapidly from correlation to causation, and ultimately to translation.

  7. Understanding Metaphorical Use of Verbs

    National Research Council Canada - National Science Library

    Torreano, Lisa

    1997-01-01

    How do people understand language in which verbs are used metaphorically? For example, how do people understand utterances such as He bathed in her beauty or She punctured his ego in everyday conversation...

  8. Understanding Informal Urban Land Market Functioning in Peri ...

    African Journals Online (AJOL)

    Since mid-1970s, a great number of rural-urban migrants are converging towards Kigali, the capital of Rwanda, and secondary towns, putting strain on land, especially of urban fringes. This is the case of Tumba Sector, a suburb of Butare Town, which attracts many people searching land for various uses. The purpose of this ...

  9. Scientific Understanding of Non-Chromated Corrosion Inhibitors Function

    Science.gov (United States)

    2013-01-01

    form an impermeable barrier on the alloy surface. This conclusion is based on the fact that the polarization resistance is 10 5 -10 6 ohm-cm 2 in air...saturated 0.5 M Na2SO4 rather than >10 6 ohm- cm 2 , as expected for more impermeable barrier coatings on aluminum alloys (Fig. 1.12). We suppose...Coating Film (2008). 2. J. J. Chen, et al. Cement and Concrete Research. 34 (2004) 1499. 3. R. C. Newton, et al. Geochimica et Cosmochimica Acta, 70

  10. Genomic and Functional Approaches to Understanding Cancer Aneuploidy.

    Science.gov (United States)

    Taylor, Alison M; Shih, Juliann; Ha, Gavin; Gao, Galen F; Zhang, Xiaoyang; Berger, Ashton C; Schumacher, Steven E; Wang, Chen; Hu, Hai; Liu, Jianfang; Lazar, Alexander J; Cherniack, Andrew D; Beroukhim, Rameen; Meyerson, Matthew

    2018-04-09

    Aneuploidy, whole chromosome or chromosome arm imbalance, is a near-universal characteristic of human cancers. In 10,522 cancer genomes from The Cancer Genome Atlas, aneuploidy was correlated with TP53 mutation, somatic mutation rate, and expression of proliferation genes. Aneuploidy was anti-correlated with expression of immune signaling genes, due to decreased leukocyte infiltrates in high-aneuploidy samples. Chromosome arm-level alterations show cancer-specific patterns, including loss of chromosome arm 3p in squamous cancers. We applied genome engineering to delete 3p in lung cells, causing decreased proliferation rescued in part by chromosome 3 duplication. This study defines genomic and phenotypic correlates of cancer aneuploidy and provides an experimental approach to study chromosome arm aneuploidy. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

  11. Understanding the Formation, Functions, and Challenges of Grassroots Leadership Teams

    Science.gov (United States)

    Lester, Jaime; Kezar, Adrianna J.

    2012-01-01

    This study examined the nature, characteristics, and challenges of grassroots leadership teams and the role of these factors in promoting cognitive complexity in order to provide insight into collective forms of bottom-up change. The study is framed by the literature on leadership teams. Using interviews from a case study conducted at five higher…

  12. Choosing the optimal spectroscopic toolkit to understand protein function.

    Science.gov (United States)

    Hough, Michael A

    2017-06-30

    Spectroscopy was one of the earliest methods used to study the properties and reactions of proteins, and remains one of the most powerful and widely used approaches to this day. A sometimes bewildering range of spectroscopies is now available, applicable to different sample states, timescales and indeed biological questions. This editorial describes some of the most relevant spectroscopic methods together with a selection of illustrative examples. © 2017 The Author(s).

  13. Understanding Effects of Traumatic Insults on Brain Structure and Function

    Science.gov (United States)

    2016-08-01

    modeled via cable equations.76 Electrical activity within each neuronal compartment was simulated using up to 15 distinct Hodgkin - Huxley type voltage...and potassium. Hodgkin - Huxley -like simulations of neuronal electrical activity include a term to represent the passive permeability of the neuronal...conditions were used for the face that has the piston. The opposing face and the boundaries in the x and y dimensions are fixed. The simulation

  14. Membrane Binding of Recoverin: From Mechanistic Understanding to Biological Functionality

    Czech Academy of Sciences Publication Activity Database

    Timr, Štěpán; Pleskot, Roman; Kadlec, Jan; Kohagen, Miriam; Magarkar, Aniket; Jungwirth, Pavel

    2017-01-01

    Roč. 3, č. 8 (2017), s. 868-874 ISSN 2374-7943 R&D Projects: GA ČR(CZ) GBP208/12/G016 Institutional support: RVO:61388963 Keywords : recoverin * membrane * myristoyl * molecular dynamics Subject RIV: CF - Physical ; Theoretical Chemistry OBOR OECD: Physical chemistry Impact factor: 7.481, year: 2016 http://pubs.acs.org/doi/full/10.1021/acscentsci.7b00210

  15. Membrane Binding of Recoverin: From Mechanistic Understanding to Biological Functionality

    Czech Academy of Sciences Publication Activity Database

    Timr, S.; Pleskot, Roman; Kadlec, J.; Kohagen, M.; Magarkar, A.; Jungwirth, P.

    2017-01-01

    Roč. 3, č. 8 (2017), s. 868-874 ISSN 2374-7943 Institutional support: RVO:61389030 Keywords : recoverin * membrane * myristoyl Subject RIV: CF - Physical ; Theoretical Chemistry OBOR OECD: Cell biology Impact factor: 7.481, year: 2016

  16. Understanding Informal Urban Land Market Functioning in Peri ...

    African Journals Online (AJOL)

    done orally with an unofficial sale contract signed by the land seller, the buyer and a few witnesses from both side or proof .... politician, real-estate developer or community group was involved in informal land market as it is the case in ... operate as land agents on a part-time basis. They search information on land by asking ...

  17. Pitfalls in understanding the functional significance of genital allometry.

    Science.gov (United States)

    Eberhard, W; Rodriguez, R L; Polihronakis, M

    2009-03-01

    The male genitalia of arthropods consistently show negative static allometry (the genitalia of small males of a species are disproportionally large, and those of large males are disproportionally small). We discuss relations between the 'one-size-fits-all' hypothesis to explain this allometry and the regimes of selection that may be acting on genitalia. We focus on the contrasts between directional vs. stabilizing selection, and natural vs. sexual selection. In addition, we point out some common methodological problems in studies of genital allometry. One-size-fits-all types of arguments for negative allometry imply net stabilizing selection, but the effects of stabilizing selection on allometry will be weaker when the correlation between body size and the trait size is weaker. One-size-fits-all arguments can involve natural as well as sexual selection, and negative allometry can also result from directional selection. Several practical problems make direct tests of whether directional or stabilizing selection is acting difficult. One common methodological problem in previous studies has been concentration on absolute rather than relative values of the allometric slopes of genitalia; there are many reasons to doubt the usefulness of comparing absolute slopes with the usual reference value of 1.00. Another problem has been the failure to recognize that size and shape are independent traits of genitalia; rapid divergence in the shape of genitalia is thus not paradoxical with respect to the reduced variation in their sizes that is commonly associated with negative allometric scaling.

  18. Learning theory: a driving force in understanding orbitofrontal function.

    Science.gov (United States)

    McDannald, Michael A; Jones, Joshua L; Takahashi, Yuji K; Schoenbaum, Geoffrey

    2014-02-01

    Since it was demonstrated the orbitofrontal cortex (OFC) is critical to reversal learning, there has been considerable interest in specifying its role in flexible, outcome-guided behavior. Behavioral paradigms from the learning theory tradition, such as outcome devaluation, blocking, Pavlovian to instrumental transfer, and overexpectation have been a driving force in this research. The use of these procedures has revealed OFC's unique role in forming and integrating information about specific features of events and outcomes to drive behavior and learning. These studies highlight the power and importance of learning theory principles in guiding neuroscience research. Published by Elsevier Inc.

  19. Ego Function and Dysfunction: A Guide to Understanding Discipline Problems.

    Science.gov (United States)

    Henley, Martin

    1987-01-01

    In this discussion of Fritz Redl's model of ego dysfunction in disturbed children, tasks the mature ego must accomplish are described, such as frustration tolerance, temptation resistance, realism about rules and routines, and exposure to competitive challenges. The model's educational applications involve assessment of discipline problems,…

  20. 76 FR 71029 - Coordination of Functions; Memorandum of Understanding

    Science.gov (United States)

    2011-11-16

    ... deal with discrimination on the basis of race, color, religion, sex, or national origin. Further, the... contracts or subcontracts that supports the enforcement mandates of each agency as well as their joint..., religion, sex, and national origin, the Field Committees may also share information related to the...