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Sample records for variation affecting chemical

  1. Variations in the chemical composition of cassava ( Manihot esculenta Crantz) leaves and roots as affected by genotypic and environmental variation.

    Science.gov (United States)

    Burns, Anna Elizabeth; Gleadow, Roslyn Margaret; Zacarias, Anabela M; Cuambe, Constantino Estevão; Miller, Rebecca Elizabeth; Cavagnaro, Timothy Richard

    2012-05-16

    The purpose of this study was to assess the quality of cassava cultivars, in terms of cyanogenic potential and composition of macro- and micronutrients, sampled from different locations in rural Mozambique. Total cyanide concentrations in fresh cassava tissues were measured using portable cyanide testing kits, and elemental nutrients were later analyzed from dried plant tissue. Variation in cyanogenic potential and nutrient composition occurred both among cultivars and across locations. The majority of cultivars contained >100 ppm total cyanide, fresh weight, and are therefore considered to be dangerously poisonous unless adequately processed before consumption. Leaf cyanogenic and nutrient content varied with plant water status, estimated using carbon isotope discrimination (δ(13)C). The colonization of roots of all cultivars by arbuscular mycorrhizal fungi was also quantified and found to be high, indicating that mycorrhizas could play a key role in plant nutrient acquisition in these low-input farming systems.

  2. Surface variations affecting human dental enamel studied using nanomechanical and chemical analysis

    Science.gov (United States)

    Dickinson, Michelle Emma

    The enamel surface is the interface between the tooth and its ever changing oral environment. Cavity (caries) formation and extrinsic tooth staining are due, respectively, to degradation of the enamel structure under low pH conditions and interactions between salivary pellicle and dietary elements. Both of these occur at the enamel surface and are caused by the local environment changing the chemistry of the surface. The results can be detrimental to the enamel's mechanical integrity and aesthetics. Incipient carious lesions are the precursor to caries and form due to demineralisation of enamel. These carious lesions are a reversible structure where ions (e.g. Ca2+, F -) can diffuse in (remineralisation) to preserve the tooth's structural integrity. This investigation used controlled in vitro demineralisation and remineralisation to study artificial carious lesion formation and repair. The carious lesions were cross-sectioned and characterised using nanoindentation, electron probe micro-analysis and time of flight secondary ion mass spectrometry. Mechanical and chemical maps showed the carious lesion had a significantly reduced hardness and elastic modulus, and the calcium and phosphate content was lower than in sound enamel. Fluoride based remineralisation treatments gave a new phase (possibly fluorohydroxyapatite) within the lesion with mechanical properties higher than sound enamel. The acquired salivary pellicle is a protein-rich film formed by the physisorption of organic molecules in saliva onto the enamel surface. Its functions include lubrication during mastication and chemical protection. However, pellicle proteins react with dietary elements such as polyphenols (tannins in tea) causing a brown stain. This study has used in vitro dynamic nanoindentation and atomic force microscopy to examine normal and stained pellicles formed in vivo. The effects of polyphenols on the pellicle's mechanical properties and morphology have been studied. It was found that the

  3. Genetic variation of lodgepole pine, Pinus contorta var. latifolia, chemical and physical defenses that affect mountain pine beetle, Dendroctonus ponderosae, attack and tree mortality.

    Science.gov (United States)

    Ott, Daniel S; Yanchuk, Alvin D; Huber, Dezene P W; Wallin, Kimberly F

    2011-09-01

    Plant secondary chemistry is determined by both genetic and environmental factors, and while large intraspecific variation in secondary chemistry has been reported frequently, the levels of genetic variation of many secondary metabolites in forest trees in the context of potential resistance against pests have been rarely investigated. We examined the effect of tree genotype and environment/site on the variation in defensive secondary chemistry of lodgepole pine, Pinus contorta var. latifolia, against the fungus, Grosmannia clavigera (formerly known as Ophiostoma clavigerum), associated with the mountain pine beetle, Dendroctonus ponderosae. Terpenoids were analyzed in phloem samples from 887, 20-yr-old trees originating from 45 half-sibling families planted at two sites. Samples were collected both pre- and post-inoculation with G. clavigera. Significant variation in constitutive and induced terpenoid compounds was attributed to differences among families. The response to the challenge inoculation with G. clavigera was strong for some individual compounds, but primarily for monoterpenoids. Environment (site) also had a significant effect on the accumulation of some compounds, whereas for others, no significant environmental effect occurred. However, for a few compounds significant family x environment interactions were found. These results suggest that P. c. latifolia secondary chemistry is under strong genetic control, but the effects depend on the individual compounds and whether or not they are expressed constitutively or following induction.

  4. 489 SEASONAL VARIATION IN PHYSICO-CHEMICAL ...

    African Journals Online (AJOL)

    Osondu

    Abstract. This study examined the effect of seasonal variation on the physical, chemical and biological properties of groundwater around Karu abattoir. Water samples were collected from different wells at different distances around the abattoir comprising Group A (within abattoir), Group B (60m from abattoir) and Group C ...

  5. Photoionization affected by chemical anisotropy

    Science.gov (United States)

    Gladkikh, V. S.; Burshtein, A. I.

    2007-01-01

    The kinetic constants of rhodamine 3B quenching by N,N-dimethyl aniline were extracted from the very beginning of the quenching kinetics, recently studied in a few solvents of different viscosities. They were well fitted with the conventional kinetic constant definition, provided the radial distribution function of simple liquids was ascribed to the reactant pair distribution and the contact electron transfer rate was different in all the cases. This difference was attributed to the chemical anisotropy averaging by the rotation of reactants, which is the faster in solvents of lower viscosity. With the proper choice of a space dependent encounter diffusion, the whole quenching kinetics was well fitted with an encounter theory, using the Marcus [J. Chem. Phys. 24, 966 (1956); 43, 679 (1965)] transfer rate instead of the contact Collins-Kimball [J. Colloid. Sci. 4, 425 (1949)] approximation. Not only the beginning and middle part of the quenching were equally well fitted, but the long time (Markovian) rate constant was also found to be the same as previously obtained. Moreover, the concentration dependencies of the fluorescence quantum yield and the Stern-Volmer constant were specified and await their experimental verification.

  6. The effects of seasonal variation on hazardous chemical releases.

    Science.gov (United States)

    Zimmerman, Laura I; Lima, Raquel; Pietrobon, Ricardo; Marcozzi, David

    2008-02-28

    Accidental and intentional chemical releases are an increasing threat to our society. These events occur year around under different seasonal circumstances. A number of papers using the Hazardous Substances Emergency Events database (HSEES) have found some evidence that season may be an important variable affecting the number of hazardous chemical releases (HCRs). To the authors' knowledge, no analyses specifically focused on seasonal variation of HCRs. Significant effects of season are useful to further HCR prevention efforts and improve preparation and training of first responders, community evacuation, and hospital preparedness. Seasonal variation is a factor in transportation HCRs, but not fixed facility HCRs. There is an overall seasonal effect for the cause of the event. There is also seasonal variation of HCRs with respect to geographical area, with more incidents in the South. The substances released also demonstrate seasonal variation with summer having more incidents involving acids, ammonia, chlorine, pesticides, paints and dyes. The number of victims treated at hospitals resulting from HCRs did not display seasonal variation. This new additional information involving seasonal changes of HCRs adds to the literature on HCRs and may indirectly have implications for the prevention of incidents, training of personnel responding to HCRs, community planning, and local hazard vulnerability analyses and finally hospital preparedness.

  7. Origin and Chemical Variation of Brazilian Propolis

    Directory of Open Access Journals (Sweden)

    Antonio Salatino

    2005-01-01

    Full Text Available Propolis is a hive product containing chiefly beeswax and plant-derived substances such as resin and volatile compounds. Propolis has been used as an antiseptic and wound healer since ancient times and interest for the product has increased recently. Probably few plant species contribute as major resin sources. Green propolis derives mainly from vegetative apices of Baccharis dracunculifolia (alecrim plants. However, wide variation detected in the chemical composition suggests contributions from alternative resin plant sources. Predominant components of the resin of green propolis are cinnamic acids, chiefly compounds bearing prenyl groups. Terpenoid compounds, such as sesqui, di and pentacyclic triterpenoids, have been detected in many, but not all, samples investigated. Propolis research has uncovered potentialities of substances previously isolated from plants and has detected constituents of plant origin that would hardly be known otherwise.

  8. Seasonal variations of physico-chemical properties of the Great ...

    African Journals Online (AJOL)

    The present study was attempted on the physico-chemical variability of the Great Vedaranyam Swamp of the Point Calimere Wildlife Sanctuary, South-east coast of India. Seasonal variation study was carried out to examine level of varying physico-chemical parameters such as temperature, salinity, pH, dissolved oxygen, ...

  9. Exploring Chemical Bonds through Variations in Magnetic Shielding.

    Science.gov (United States)

    Karadakov, Peter B; Horner, Kate E

    2016-02-09

    Differences in nuclear isotropic magnetic shieldings give rise to the chemical shifts measured in NMR experiments. In contrast to existing NMR experimental techniques, quantum chemical methods are capable of calculating isotropic magnetic shieldings not just at nuclei, but also at any point in the space surrounding a molecule. Using s-trans-1,3-butadiene, ethane, ethene, and ethyne as examples, we show that the variations in isotropic magnetic shielding around a molecule, represented as isosurfaces and contour plots, provide an unexpectedly clear picture of chemical bonding, which is much more detailed than the traditional description in terms of the total electron density.

  10. Seasonal variations of physico-chemical characteristics in water ...

    African Journals Online (AJOL)

    The influence of seasonal changes on the physico-chemical characteristics of water resources quality in the western horn of the Niger Delta region of Nigeria has been investigated. The water resources investigated were rain, open well and borehole water. The seasonal temperature variations show the waters to be in a ...

  11. Seasonal Variations of Some Physico-Chemical Properties of River ...

    African Journals Online (AJOL)

    MICHAEL

    Environ. Manage. March, 2009. Vol. 13(1) 55 - 57. Full-text Available Online at www.bioline.org.br/ja. Seasonal Variations of Some Physico-Chemical Properties of River Ethiope Water in. Abraka, Nigeria. 1AGBAIRE, P.O.; OBI, C.G.. 1Department of Chemistry, Delta State University P.M.B. 1, Abraka Delta State, Nigeria.

  12. Huntingtin gene repeat size variations affect risk of lifetime depression

    DEFF Research Database (Denmark)

    Gardiner, Sarah L.; van Belzen, Martine J.; Boogaard, Merel W.

    2017-01-01

    Huntington disease (HD) is a severe neuropsychiatric disorder caused by a cytosine-adenine-guanine (CAG) repeat expansion in the HTT gene. Although HD is frequently complicated by depression, it is still unknown to what extent common HTT CAG repeat size variations in the normal range could affect...... as hitherto unappreciated but complex genetic modifiers of depression.......Huntington disease (HD) is a severe neuropsychiatric disorder caused by a cytosine-adenine-guanine (CAG) repeat expansion in the HTT gene. Although HD is frequently complicated by depression, it is still unknown to what extent common HTT CAG repeat size variations in the normal range could affect...... depression risk in the general population. Using binary logistic regression, we assessed the association between HTT CAG repeat size and depression risk in two well-characterized Dutch cohorts─the Netherlands Study of Depression and Anxiety and the Netherlands Study of Depression in Older Persons...

  13. Four dimensional variational inversion of atmospheric chemical sources in WRFDA

    Science.gov (United States)

    Guerrette, J. J.

    Atmospheric aerosols are known to affect health, weather, and climate, but their impacts on regional scales are uncertain due to heterogeneous source, transport, and transformation mechanisms. The Weather Research and Forecasting model with chemistry (WRF-Chem) can account for aerosol-meteorology feedbacks as it simultaneously integrates equations of dynamical and chemical processes. Here we develop and apply incremental four dimensional variational (4D-Var) data assimilation (DA) capabilities in WRF-Chem to constrain chemical emissions (WRFDA-Chem). We develop adjoint (ADM) and tangent linear (TLM) model descriptions of boundary layer mixing, emission, aging, dry deposition, and advection of black carbon (BC) aerosol. ADM and TLM model performance is verified against finite difference derivative approximations. A second order checkpointing scheme is used to reduce memory costs and enable simulations longer than six hours. We apply WRFDA-Chem to constraining anthropogenic and biomass burning sources of BC throughout California during the 2008 Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) field campaign. Manual corrections to the prior emissions and subsequent inverse modeling reduce the spread in total emitted BC mass between two biomass burning inventories from a factor of x10 to only x2 across three days of measurements. We quantify posterior emission variance using an eigendecomposition of the cost function Hessian matrix. We also address the limited scalability of 4D-Var, which traditionally uses a sequential optimization algorithm (e.g., conjugate gradient) to approximate these Hessian eigenmodes. The Randomized Incremental Optimal Technique (RIOT) uses an ensemble of TLM and ADM instances to perform a Hessian singular value decomposition. While RIOT requires more ensemble members than Lanczos requires iterations to converge to a comparable posterior control vector, the wall-time of RIOT is x10 shorter since the

  14. Chemical and non-chemical stressors affecting childhood obesity: a systematic scoping review.

    Science.gov (United States)

    Lichtveld, Kim; Thomas, Kent; Tulve, Nicolle S

    2018-01-01

    Childhood obesity in the United States has doubled over the last three decades and currently affects 17% of children and adolescents. While much research has focused on individual behaviors impacting obesity, little research has emphasized the complex interactions of numerous chemical and non-chemical stressors found in a child's environment and how these interactions affect a child's health and well-being. The objectives of this systematic scoping review were to (1) identify potential chemical stressors in the context of non-chemical stressors that impact childhood obesity; and, (2) summarize our observations for chemical and non-chemical stressors in regards to child-specific environments within a community setting. A review was conducted to identify chemical and non-chemical stressors related to childhood obesity for the childhood life stages ranging from prenatal to adolescence. Stressors were identified and grouped into domains: individual behaviors, family/household behaviors, community stressors, and chemical exposures. Stressors were related to the child and the child's everyday environments and used to characterize child health and well-being. This review suggests that the interactions of chemical and non-chemical stressors are important for understanding a child's overall health and well-being. By considering these relationships, the exposure science research community can better design and implement strategies to reduce childhood obesity.

  15. Genetic variation in genes affecting milk composition and quality

    DEFF Research Database (Denmark)

    Bertelsen, Henriette Pasgaard

    In the past decade major advances in next generation sequencing technologies have provided new opportuneties for the detection of genetic variation. Combining the knowlegde of genetic variation with phenotypic distributions provides considerable possibilites for detection of candidate genes....... In addition, exploring genetic variation related to the major milk proteins of bovine milk indntified genetic variations with possitive effects on milk coagulation...

  16. Detection of Cell Wall Chemical Variation in Zea Mays Mutants Using Near-Infrared Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Buyck, N.; Thomas, S.

    2001-01-01

    Corn stover is regarded as the prime candidate feedstock material for commercial biomass conversion in the United States. Variations in chemical composition of Zea mays cell walls can affect biomass conversion process yields and economics. Mutant lines were constructed by activating a Mu transposon system. The cell wall chemical composition of 48 mutant families was characterized using near-infrared (NIR) spectroscopy. NIR data were analyzed using a multivariate statistical analysis technique called Principal Component Analysis (PCA). PCA of the NIR data from 349 maize leaf samples reveals 57 individuals as outliers on one or more of six Principal Components (PCs) at the 95% confidence interval. Of these, 19 individuals from 16 families are outliers on either PC3 (9% of the variation) or PC6 (1% of the variation), the two PCs that contain information about cell wall polymers. Those individuals for which altered cell wall chemistry is confirmed with wet chemical analysis will then be subjected to fermentation analysis to determine whether or not biomass conversion process kinetics, yields and/or economics are significantly affected. Those mutants that provide indications for a decrease in process cost will be pursued further to identify the gene(s) responsible for the observed changes in cell wall composition and associated changes in process economics. These genes will eventually be incorporated into maize breeding programs directed at the development of a truly dual use crop.

  17. Variation in chemical profiles within large seizures of cocaine bricks.

    Science.gov (United States)

    Stride Nielsen, Louise; Villesen, Palle; Lindholst, Christian

    2017-11-01

    Cocaine is usually trafficked from South America throughout the world in packages of approximately one kilogram shaped as bricks and imprinted with a logo. Seizures consisting of multiple cocaine bricks gives the opportunity to examine the variation in the chemical profile within cocaine bricks assumed to originate from the same manufacturer and maybe even the same production batch. This knowledge may be important to the forensic investigator when chemical profiles from cocaine samples of unknown origin are compared. In the present study, the alkaloid and residual solvent profiles from three large cocaine seizures each containing identical cocaine bricks was examined. The three cases consisted of 36, 84 and 100 cocaine bricks, respectively. Each cocaine brick was profiled according to its cocaine alkaloid and residual solvent content using gas chromatography-mass spectrometry (GC-MS) and headspace GC-MS. The study showed that each of the three identical looking seizures consisted of up to four groups of cocaine bricks displaying the same cocaine alkaloid and residual solvent profile. The size of the groups varied from 2.4 to 63.3kg cocaine. The study also showed that the residual solvent profile within each of the three large seizures exhibited very little variation whereas the alkaloid profile varied considerably more. This finding suggest that the same organic solvent is used for the production of several batches of cocaine HCl. Therefore, the residual solvent profile may be a tool to link different production batches from the same manufacturer even though the alkaloid profile are different. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Relevant Spatial Scales of Chemical Variation in Aplysina aerophoba

    Directory of Open Access Journals (Sweden)

    Oriol Sacristan-Soriano

    2011-11-01

    Full Text Available Understanding the scale at which natural products vary the most is critical because it sheds light on the type of factors that regulate their production. The sponge Aplysina aerophoba is a common Mediterranean sponge inhabiting shallow waters in the Mediterranean and its area of influence in Atlantic Ocean. This species contains large concentrations of brominated alkaloids (BAs that play a number of ecological roles in nature. Our research investigates the ecological variation in BAs of A. aerophoba from a scale of hundred of meters to thousand kilometers. We used a nested design to sample sponges from two geographically distinct regions (Canary Islands and Mediterranean, over 2500 km, with two zones within each region (less than 50 km, two locations within each zone (less than 5 km, and two sites within each location (less than 500 m. We used high-performance liquid chromatography to quantify multiple BAs and a spectrophotometer to quantify chlorophyll a (Chl a. Our results show a striking degree of variation in both natural products and Chl a content. Significant variation in Chl a content occurred at the largest and smallest geographic scales. The variation patterns of BAs also occurred at the largest and smallest scales, but varied depending on which BA was analyzed. Concentrations of Chl a and isofistularin-3 were negatively correlated, suggesting that symbionts may impact the concentration of some of these compounds. Our results underline the complex control of the production of secondary metabolites, with factors acting at both small and large geographic scales affecting the production of multiple secondary metabolites.

  19. Thallium isotope variations in anthropogenically-affected soils

    Science.gov (United States)

    Vanek, Ales; Chrastny, Vladislav; Penizek, Vit; Mihaljevic, Martin; Komarek, Michael; Cabala, Jerzy

    2014-05-01

    Our preliminary data from soils impacted by long-term Tl deposition in the vicinity of a primary/secondary Zn smelter at Olkusz (Poland) indicate apparent variability of ɛ205Tl within soil profiles. The identified ɛ205Tl values presented for the forest soil profile reached -1.7 in the surface/organic horizon, +1.9 in the organo-mineral horizon (Ap), and +1.0 in the mineral horizon (C). This finding suggests both the enrichment of 203Tl isotope in the topsoil, as well as its preferential release during smelting operations, as "lighter" Tl tends to enter the emissions during a high-temperature process. The maximum ɛ205Tl value in the subsurface horizon Ap is in accordance with the concentration peak of oxalate-extractable Mn, indicating the presence of amorphous/poorly-crystalline Mn oxides with a potential to isotopically fractionate Tl toward the "heavier" fraction. The Tl isotope signature in the bottom horizon probably reflects the composition of a local geochemical anomaly of Tl. However, a portion of mobile (anthropogenic) Tl with negative ɛ205Tl moving downwards in the soil profile cannot be neglected. In general, there is no detailed information about the biogeochemical cycling and variations of Tl isotopes in areas affected by significant anthropogenic inputs of the metal (e.g., coal burning and primary metallurgy); the questions of the degree to which the factors such as soil (and sediment) chemistry, mineralogy, local biota, and pollution source control Tl isotope fractionation remain unresolved. Therefore, further research on the topic is needed before any principal conclusions will be made.

  20. Chemical and Conformational Diversity of Modified Nucleosides Affects tRNA Structure and Function

    Directory of Open Access Journals (Sweden)

    Ville Y. P. Väre

    2017-03-01

    Full Text Available RNAs are central to all gene expression through the control of protein synthesis. Four major nucleosides, adenosine, guanosine, cytidine and uridine, compose RNAs and provide sequence variation, but are limited in contributions to structural variation as well as distinct chemical properties. The ability of RNAs to play multiple roles in cellular metabolism is made possible by extensive variation in length, conformational dynamics, and the over 100 post-transcriptional modifications. There are several reviews of the biochemical pathways leading to RNA modification, but the physicochemical nature of modified nucleosides and how they facilitate RNA function is of keen interest, particularly with regard to the contributions of modified nucleosides. Transfer RNAs (tRNAs are the most extensively modified RNAs. The diversity of modifications provide versatility to the chemical and structural environments. The added chemistry, conformation and dynamics of modified nucleosides occurring at the termini of stems in tRNA’s cloverleaf secondary structure affect the global three-dimensional conformation, produce unique recognition determinants for macromolecules to recognize tRNAs, and affect the accurate and efficient decoding ability of tRNAs. This review will discuss the impact of specific chemical moieties on the structure, stability, electrochemical properties, and function of tRNAs.

  1. Evolution of polymer photovoltaic performances from subtle chemical structure variations.

    Science.gov (United States)

    Yan, Han; Li, Denghua; Lu, Kun; Zhu, Xiangwei; Zhang, Yajie; Yang, Yanlian; Wei, Zhixiang

    2012-11-21

    Conjugated polymers are promising replacements for their inorganic counterparts in photovoltaics due to their low cost, ease of processing, and straightforward thin film formation. New materials have been able to improve the power conversion efficiency of photovoltaic cells up to 8%. However, rules for rational material design are still lacking, and subtle chemical structure variations usually result in large performance discrepancies. The present paper reports a detailed study on the crystalline structure, morphology, and in situ optoelectronic properties of blend films of polythiophene derivatives and [6,6]-phenyl C61-butyric acid methyl ester by changing the alkyl side chain length and position of polythiophene. The correlation among the molecular structure, mesoscopic morphology, mesoscopic optoelectronic property and macroscopic device performance (highest efficiency above 4%) was directly established. Both solubility and intermolecular interactions should be considered in rational molecular design. Knowledge obtained from this study can aid the selection of appropriate processing conditions that improve blend film morphology, charge transport property, and overall solar cell efficiency.

  2. Are variations in PMSE intensity affected by energetic particle precipitation?

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    V. Barabash

    2002-04-01

    Full Text Available The correlation between variations in Polar Mesosphere Summer Echoes (PMSE and variations in energetic particle precipitation is examined. PMSE were observed by the Esrange VHF MST Radar (ESRAD at 67°53' N, 21°06' E. The 30 MHz riometer in Abisko (68°24' N, 18°54' E registered radio wave absorption caused by ionization changes in response to energetic particle precipitation. The relationship between the linear PMSE intensity and the square of absorption has been estimated using the Pearson linear correlation and the Spearman rank correlation. The mean diurnal variation of the square of absorption and the linear PMSE intensity are highly correlated. However, their day-to-day variations show significant correlation only during the late evening hours. The correlation in late evening does not exceed 0.6. This indicates that varying ionization cannot be considered as a primary source of varying PMSE, and the high correlation found when mean diurnal variations are compared is likely a by-product of daily variations caused by other factors.Key words. Ionosphere (particle precipitation Magnetospheric physics (energetic particles, precipitating Meteorology and atmospheric dynamics (precipitation

  3. Are variations in PMSE intensity affected by energetic particle precipitation?

    Directory of Open Access Journals (Sweden)

    V. Barabash

    Full Text Available The correlation between variations in Polar Mesosphere Summer Echoes (PMSE and variations in energetic particle precipitation is examined. PMSE were observed by the Esrange VHF MST Radar (ESRAD at 67°53' N, 21°06' E. The 30 MHz riometer in Abisko (68°24' N, 18°54' E registered radio wave absorption caused by ionization changes in response to energetic particle precipitation. The relationship between the linear PMSE intensity and the square of absorption has been estimated using the Pearson linear correlation and the Spearman rank correlation. The mean diurnal variation of the square of absorption and the linear PMSE intensity are highly correlated. However, their day-to-day variations show significant correlation only during the late evening hours. The correlation in late evening does not exceed 0.6. This indicates that varying ionization cannot be considered as a primary source of varying PMSE, and the high correlation found when mean diurnal variations are compared is likely a by-product of daily variations caused by other factors.

    Key words. Ionosphere (particle precipitation Magnetospheric physics (energetic particles, precipitating Meteorology and atmospheric dynamics (precipitation

  4. Factors affecting yearly variations of indoor radon concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Steck, D.J.; Baynes, S.A. [John`s Univ., Collegeville, MN (United States)

    1996-06-01

    Since indoor radon exposures take place over many years while radon measurement periods are shorter, we are studying the yearly variation of indoor radon concentrations in approximately 100 houses located throughout Minnesota. Most houses were initially measured for one or more years in the late 1980`s and for 5 consecutive years starting in 1990. Two houses have been monitored for 12 y. Each year, two alpha track detectors were placed on the two lowest livable levels. The year-to-year variations averaged about 35% (corrected for instrumental uncertainties) in both basements and first floors. The minimum observed variation was 5% and the maximum was 130%. Some homes have shown substantial variation associated with Structural modifications. While most homes show no obvious systematic trends, a few houses have shown temporal trends that may be associated with aging or climate. We are studying possible correlation between year-to-year radon variation, climatic variables (yearly-average and seasonal such as heating/cooling degree days, precipitation, soil moisture), and structural changes.

  5. Copy number variations in affective disorders and meta-analysis

    DEFF Research Database (Denmark)

    Olsen, Line; Hansen, Thomas; Djurovic, Srdjan

    2011-01-01

    In two recent studies 10 copy number variants (CNV) were found to be overrepresented either among patients suffering from affective disorders in an Amish family or in the Wellcome Trust Case-Control Consortium study. Here, we investigate if these variants are associated with affective disorders...

  6. Landscape location affects genetic variation of Canada lynx (Lynx canadensis)

    Science.gov (United States)

    M. K. Schwartz; L. S. Mills; Y. Ortega; L. F. Ruggiero; F. W. Allendorf

    2003-01-01

    The effect of a population's location on the landscape on genetic variation has been of interest to population genetics for more than half a century. However, most studies do not consider broadscale biogeography when interpreting genetic data. In this study, we propose an operational definition of a peripheral population, and then explore whether peripheral...

  7. Geographic and Temporal Variation in Moth Chemical Communication

    Science.gov (United States)

    Unlike acoustic and visual communication, chemical communication cues have not been viewed in the background of a chemically noisy habitat. Species with similar chemical cues may not only directly interfere with each other's communication channels, but the presence and abundance of other species may...

  8. Phenotypes of individuals affected by airborne chemicals in the general population

    DEFF Research Database (Denmark)

    Berg, Nikolaj Drimer; Linneberg, A.; Dirksen, Asger

    2009-01-01

    OBJECTIVE: To characterise the chemical exposures and symptoms affecting individuals with subsequent adjustments of social life or occupational conditions, and further characterise these severely affected individuals. METHODS: All individuals (n = 1,134) who reported symptoms from airborne chemic...

  9. Variation in postsampling treatment of avian blood affects ecophysiological interpretations

    NARCIS (Netherlands)

    Hoye, B.J.

    2012-01-01

    1. The fluid component of blood is widely used in ecophysiological investigations, including measures of immune function and stable isotope ecology. After blood collection, delayed separation of blood extracellular fluids from red blood cells is known to affect the concentration of a wide range of

  10. Genotypic variation in tomatoes affecting processing and antioxidant attributes.

    Science.gov (United States)

    Siddiqui, Mohammed Wasim; Ayala-Zavala, J F; Dhua, R S

    2015-01-01

    Tomatoes are widely consumed either raw or after processing and can provide a significant proportion of the total antioxidants in the diet associated with beneficial health properties. Over the last two or three decades an increasing interest for processing and antioxidant attributes in tomatoes has arisen. The screening of processing attributes of tomatoes is subject of a large number of articles; however, special interest has been addressed to the biochemical composition. The postharvest and industrial processing of tomato in tomato-based products includes several steps. Processing and antioxidant characteristics of the raw fruit are important considering the processing steps and final product. To respond to consumer and industrial complaints, breeders should know the range of genetic variability available in tomato resources, including local genotypes, for improving the mentioned attributes. Characterization and conservation of traditional and modern varieties is a major goal for their preservation and utilization. The bioactive contents have an impact on the processed destines so their stability must be contemplated while selecting the tomato fruits for processing. The endeavor of this review was to examine comprehensively the variation in processing and antioxidant attributes among tomatoes. Role of tomato peel in terms of bioactive contents and information on high pigment (hp) tomato mutants are also touched to some extent. Probably, patterns of variation identified/discussed in this paper would give impetus for planning breeding strategies to develop and improve the new processing cultivars with good antioxidant status.

  11. Impacts of hydrologic variations on chemical weathering and solute sources in the Min River basin, Himalayan-Tibetan region.

    Science.gov (United States)

    Zhong, Jun; Li, Si-Liang; Tao, Faxiang; Ding, Hu; Liu, Jing

    2017-08-01

    Feedback between hydrologic variations and chemical weathering is thought to play a crucial role in modulating global carbon cycling. The mechanisms associated with the impacts of hydrologic variations on solute sources and chemical weathering were evaluated by examining the relationships between river discharge and hydrochemistry based on high-frequency sampling of the Min River, which originates in the Himalayan-Tibetan region. Fluid transit times and flow pathways vary with changes in discharge, thereby affecting various biogeochemical processes. Although shorter transit times occur during the high-flow season than during the low-flow season, concentrations of chemical weathering products exhibit chemostatic behaviour (less variation than changes in discharge) in response to increasing discharge due to hydrologic flushing of minerals, which increases the amount of reactive mineral surface area. The contributions of various sources to dissolved loads in the Min River were estimated using a forward model. The calculated annual carbonate and silicate weathering fluxes are 24.1 and 9.6 t/km2 year, respectively. Atmospheric contributions increase with increasing discharge, whereas the contributions of silicate weathering decrease with increasing discharge. Both the carbonate weathering flux (FCarb) and silicate weathering flux (FSil) are positively correlated with the discharge, indicating that temporal variations in chemical weathering fluxes in the Min River are highly affected by hydrologic variations. The slope of the relationship between FCarb and discharge is much greater than that between FSil and discharge due to the rapid dissolution of carbonate minerals, suggesting that carbonate weathering is more sensitive than silicate weathering to hydrologic variations. This study demonstrates that high-frequency sampling is necessary when investigating solute sources and chemical weathering processes in river basins influenced by a monsoon climate.

  12. Variations in the physico-chemical properties of Dal Lake, Srinagar ...

    African Journals Online (AJOL)

    Basic physical and chemical characteristics of the water in Dal lake Srinagar were determined. Surface water was sampled on monthly basis from June 2010 to April 2011. To determine the variations in physico-chemical parameters of Dal lake, a total of 21 physico-chemical parameters from six different site spread in four ...

  13. Insect prey characteristics affecting regional variation in chimpanzee tool use.

    Science.gov (United States)

    Sanz, Crickette M; Deblauwe, Isra; Tagg, Nikki; Morgan, David B

    2014-06-01

    It is an ongoing interdisciplinary pursuit to identify the factors shaping the emergence and maintenance of tool technology. Field studies of several primate taxa have shown that tool using behaviors vary within and between populations. While similarity in tools over spatial and temporal scales may be the product of socially learned skills, it may also reflect adoption of convergent strategies that are tailored to specific prey features. Much has been claimed about regional variation in chimpanzee tool use, with little attention to the ecological circumstances that may have shaped such differences. This study examines chimpanzee tool use in termite gathering to evaluate the extent to which the behavior of insect prey may dictate chimpanzee technology. More specifically, we conducted a systematic comparison of chimpanzee tool use and termite prey between the Goualougo Triangle in the Republic of Congo and the La Belgique research site in southeast Cameroon. Apes at both of these sites are known to use tool sets to gather several species of termites. We collected insect specimens and measured the characteristics of their nests. Associated chimpanzee tool assemblages were documented at both sites and video recordings were conducted in the Goualougo Triangle. Although Macrotermitinae assemblages were identical, we found differences in the tools used to gather these termites. Based on measurements of the chimpanzee tools and termite nests at each site, we concluded that some characteristics of chimpanzee tools were directly related to termite nest structure. While there is a certain degree of uniformity within approaches to particular tool tasks across the species range, some aspects of regional variation in hominoid technology are likely adaptations to subtle environmental differences between populations or groups. Such microecological differences between sites do not negate the possibility of cultural transmission, as social learning may be required to transmit

  14. Host plant affects morphometric variation of Diaphorina citri (Hemiptera: Liviidae).

    Science.gov (United States)

    Paris, Thomson M; Allan, Sandra A; Hall, David G; Hentz, Matthew G; Hetesy, Gabriella; Stansly, Philip A

    2016-01-01

    The Asian citrus psyllid (ACP), Diaphorina citri Kuwayama, is one of the most serious citrus pests worldwide due to its role as vector of huanglongbing or citrus greening disease. While some optimal plant species for ACP oviposition and development have been identified, little is known of the influence of host plants on ACP size and shape. Our goal was to determine how size and shape of ACP wing and body size varies when development occurs on different host plants in a controlled rearing environment. ACP were reared on six different rutaceous species; Bergera koenigii, Citrus aurantifolia, Citrus macrophylla, Citrus maxima, Citrus taiwanica and Murraya paniculata. Adults were examined for morphometric variation using traditional and geometric analysis based on 12 traits or landmarks. ACP reared on C. taiwanica were consistently smaller than those reared on the other plant species. Wing aspect ratio also differed between C. maxima and C. taiwanica. Significant differences in shape were detected with those reared on M. paniculata having narrower wings than those reared on C. macrophylla. This study provides evidence of wing size and shape differences of ACP based on host plant species which potentially may impact dispersal. Further study is needed to determine if behavioral and physiological differences are associated with the observed phenotypic differences.

  15. Host plant affects morphometric variation of Diaphorina citri (Hemiptera: Liviidae

    Directory of Open Access Journals (Sweden)

    Thomson M. Paris

    2016-11-01

    Full Text Available The Asian citrus psyllid (ACP, Diaphorina citri Kuwayama, is one of the most serious citrus pests worldwide due to its role as vector of huanglongbing or citrus greening disease. While some optimal plant species for ACP oviposition and development have been identified, little is known of the influence of host plants on ACP size and shape. Our goal was to determine how size and shape of ACP wing and body size varies when development occurs on different host plants in a controlled rearing environment. ACP were reared on six different rutaceous species; Bergera koenigii, Citrus aurantifolia, Citrus macrophylla, Citrus maxima, Citrus taiwanica and Murraya paniculata. Adults were examined for morphometric variation using traditional and geometric analysis based on 12 traits or landmarks. ACP reared on C. taiwanica were consistently smaller than those reared on the other plant species. Wing aspect ratio also differed between C. maxima and C. taiwanica. Significant differences in shape were detected with those reared on M. paniculata having narrower wings than those reared on C. macrophylla. This study provides evidence of wing size and shape differences of ACP based on host plant species which potentially may impact dispersal. Further study is needed to determine if behavioral and physiological differences are associated with the observed phenotypic differences.

  16. Listening to music affects diurnal variation in muscle power output.

    Science.gov (United States)

    Chtourou, H; Chaouachi, A; Hammouda, O; Chamari, K; Souissi, N

    2012-01-01

    The purpose of this investigation was to assess the effects of listening to music while warming-up on the diurnal variations of power output during the Wingate test. 12 physical education students underwent four Wingate tests at 07:00 and 17:00 h, after 10 min of warm-up with and without listening to music. The warm-up consisted of 10 min of pedalling at a constant pace of 60 rpm against a light load of 1 kg. During the Wingate test, peak and mean power were measured. The main finding was that peak and mean power improved from morning to afternoon after no music warm-up (pmusic warm-up. Moreover, peak and mean power were significantly higher after music than no music warm-up during the two times of testing. Thus, as it is a legal method and an additional aid, music should be used during warm-up before performing activities requiring powerful lower limbs' muscles contractions, especially in the morning competitive events. © Georg Thieme Verlag KG Stuttgart · New York.

  17. Do variations in leaf phenology affect radial growth variations in Fagus sylvatica?

    Science.gov (United States)

    Čufar, Katarina; De Luis, Martin; Prislan, Peter; Gričar, Jožica; Črepinšek, Zalika; Merela, Maks; Kajfež-Bogataj, Lučka

    2015-08-01

    We used a dendrochronological and leaf phenology network of European beech (Fagus sylvatica) in Slovenia, a transitional area between Mediterranean, Alpine and continental climatic regimes, for the period 1955-2007 to test whether year to year variations in leaf unfolding and canopy duration (i.e. time between leaf unfolding and colouring) influence radial growth (annual xylem production and tree ring widths) and if such influences are more pronounced at higher altitudes. We showed that variability in leaf phenology has no significant effect on variations in radial growth. The results are consistent in the entire region, irrespective of the climatic regime or altitude, although previous studies have shown that leaf phenology and tree ring variation depend on altitude. The lack of relationship between year to year variability in leaf phenology and radial growth may suggest that earlier leaf unfolding--as observed in a previous study--probably does not cause increased tree growth rates in beech in Slovenia.

  18. Chemical treatment response to variations in non-point pollution water quality: results of a factorial design experiment.

    Science.gov (United States)

    Heiderscheidt, Elisangela; Leiviskä, Tiina; Kløve, Bjørn

    2015-03-01

    Chemical treatment of non-point derived pollution often suffers from undesirable oscillations in purification efficiency due to variations in runoff water quality. This study examined the response of the chemical purification process to variations in water quality using a 2(k) factorial design for runoff water rich in humic substances. The four k factors evaluated and the levels applied were: organic matter as dissolved organic carbon (DOC) (20-70 mg/L), suspended solids (SS) (10-60 mg/L), initial water pH (4.5-7), and applied coagulant dosage (ferric sulphate) (35-100 mg/L). Indicators of purification efficiency were residual concentration of DOC, SS and total phosphorus (tot-P). Analysis of variance and factor effect calculations showed that the initial DOC concentration in raw water samples and its interactions with the coagulant dosage applied exerted the most significant influence on the chemical purification process, substantially affecting the residual concentration of DOC, SS and tot-P. The variations applied to the factors SS and pH only slightly affected purification efficiency. The results can be used in the design of purification systems with high organic matter load variation, e.g. peat extraction runoff. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. PETN: Variation in Physical and Chemical Characteristics Related to Aging.

    Energy Technology Data Exchange (ETDEWEB)

    Monroe, D. C. (Dierdre Christina); Laintz, K. E. (Kenneth E.); Kramer, J. F. (John F.); Peterson, P. D. (Paul D.)

    2006-01-01

    Physical and chemical analyses of five PETN (pentaerythritol tetranitrate) batches have been conducted to assist in defining powder acceptance criteria for qualification of newly manufactured powders, as well as for examination of potential changes related to aging and thus changes in performance. Results showed that (1) repeatable Fisher Sub-Sieve Sizer measurements (which relate well to historic performance data) could be obtained with consistent sample setup and measurement techniques; (2) BET nitrogen adsorption estimates of surface area correlate well with Fisher measurements and appear less variable; (3) PharmaVision particle size analyses show promise in discriminating among PETN batches; and (4) SEMs are extremely useful in semi-quantitative discrimination among batches. Physical and chemical data will be related to performance data (to be obtained) to develop quantitative physical and chemical tests useful in predicting performance over time, i.e., as powders age.

  20. Geophysical evidence for chemical variations in the Australian continental mantle

    NARCIS (Netherlands)

    Gerven, van L.P.A.; Deschamps, F.; Hilst, R.D.

    2004-01-01

    The relative density-to-shear velocity scaling (¿) provides a diagnostic for the presence of compositional variations in the mantle. We invert shear-wave velocity from a recent 3-D model and gravity anomalies for radial profiles of ¿ of the uppermost mantle beneath Australia. We performed

  1. Geophysical evidence for chemical variations in the Australian Continental Mantle

    NARCIS (Netherlands)

    Gerven, Luuk van; Deschamps, Frédéric; Hilst, R.D. van der

    2004-01-01

    The relative density-to-shear velocity scaling (ζ) provides a diagnostic for the presence of compositional variations in the mantle. We invert shear-wave velocity from a recent 3-D model and gravity anomalies for radial profiles of ζ of the uppermost mantle beneath Australia. We performed

  2. Variation of the chemical composition of four forage shrubs ( Albizia ...

    African Journals Online (AJOL)

    Methodology and results: The leaves of each species were harvested at the beginning, at mid-season and at the end of dry season. They were dried and crushed to determine their chemical composition. The results showed that, with A. lebbeck, the levels of DM obtained at mid-season and the end that one, were higher ...

  3. Monthly variation of some physico-chemical and microbiological ...

    African Journals Online (AJOL)

    Canakkale, Turkey) in the months of October 2007 – September 2008 for the analyzing of some physico-chemical and microbiological parameters of the stream. In the present investigation, the mean average value (mean ±SD) of the stream ...

  4. Chemical maturation of a bivalent aptamer by single domain variation

    DEFF Research Database (Denmark)

    Rohrbach, Falk; Fatthalla, Maha I.; Kupper, Tina

    2012-01-01

    Two-pronged attack: We describe the maturation of a bivalent aptamer by a chemically driven two-step process. From an improved monovalent aptamer subdomain that had been modified by polycyclic aromatic hydrocarbons at individual positions, a mature bivalent variant with superior activities to its...

  5. Seasonal variation in chemical composition, aroma volatiles and ...

    African Journals Online (AJOL)

    TSS and TA showed strong relationships with most of the chemical indices, each showing significantly (p < 0.05) strong correlations with phenolic components as well as with the antioxidant capacity (FRAP and DPPH) measured. There were no significant (p < 0.05) seasonal effects on juice absorbance (colouration) and TA ...

  6. Variation in physico-chemical properties of seed of selected ...

    African Journals Online (AJOL)

    Seed coat colour plays no significant role in the chemical content of the seed. The physicochemical properties evaluated generally had high broad sense heritability (56 - 99%). Cowpea varieties (IT97K-1101-5 and IT89KD-288) with high protein content could be selected for formulating infant feeds, varieties with lower

  7. Seasonal and species variation in chemical composition of five ...

    African Journals Online (AJOL)

    ABUBAKER

    Association of Official Analytical Chemists,. International ®. AOAC International, Gaithersburg, Maryland. Batista, A.M.V., Mustafa, A.F., Santos, G.R.A., de Carvalho, F.F.R., Dubeux Jr, J.C.B., Lira, M.A. &. Barbosa, S.B.P., 2003. Chemical composition and ruminal dry matter and crude protein degradability of spineless cactus.

  8. Variation in size, morphology and chemical composition of polymetallic nodules from the Central Indian Ocean Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Valsangkar, A.B.; Karisiddaiah, S.M.; Parthiban, G.

    Chemical composition of 613 polymetallic nodules from 150 stations in the Central Indian Ocean Basin (CIOB) are determined and variations in Mn, Fe, Cu, Ni, Co, Zn and moisture content are studied with respect to their size and surface texture...

  9. Variation of physico-chemical characteristics with tide in Visakhapatnam harbour waters, east coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    RamaRaju, V.S.; Rao, T.V.N.; Rathod, V.

    fluctuations in physico-chemical parameters at st A (northwestern arm) may be attributed to the closeness of the station of the discharge point of industrial pollutants. No significant variation is found during a tidal cycle in bottom water. Variations in wind...

  10. Negative affect is associated with development and persistence of chemical intolerance

    DEFF Research Database (Denmark)

    Skovbjerg, Sine; Christensen, Karl Bang; Ebstrup, Jeanette Frost

    2015-01-01

    OBJECTIVE: Chemical intolerance (CI) is characterised by negative health effects attributed to a heightened responsiveness to common airborne chemicals. This longitudinal study explored the hypothesised role of negative affect in the development and persistence of CI in a general population...

  11. Chemical studies of H chondrites. 5: Temporal variations of sources

    Science.gov (United States)

    Michlovich, Edward S.; Wolf, Stephen F.; Wang, Ming-Sheng; Vogt, Stephan; Elmore, David; Lipschutz, Michael E.

    1995-01-01

    We report Cl-36 (301-kyr half-life) data obtained by accelerator mass spectrometry allowing nominal terrestrial ages to be determined for 39 Antarctic H4-6 chondrites for which contents of volatile trace elements are known. The compositional difference between these Antarctic meteorites and 58 non-Antarctic falls increases with terrestrial age and, using multivariate statistical techniques, becomes highly significant for Antarctic samples with ages greater than 50 kyr. The compositional difference is inconsistent with trivial causes such as weathering and seems to reflect differences in thermal histories of parent sources. Temporal source variations for the H chondrite flux on Earth thus exist not only on a short-term, 40 years, basis (Dodd et al., 1993) but also on a long-term, greater than 50 kyr, basis.

  12. Variations in 5-HTTLPR: relation to familiar risk of affective disorder, life events, neuroticism and cortisol

    DEFF Research Database (Denmark)

    Vinberg, Maj; Mellerup, Erling; Andersen, Per Kragh

    2009-01-01

    BACKGROUND: Variations in the serotonin transporter gene (5-HTTLPR) and stressful life events are associated with affective disorders. AIM: To investigate whether the distribution of the alleles of the 5-HTTLPR is associated with a genetic predisposition to affective disorder and whether...

  13. Spatial variation of the chemical composition of lake waters in the Tatra National Park

    Directory of Open Access Journals (Sweden)

    Wolanin Anna

    2015-09-01

    Full Text Available The aim of this study is to determine the factors affecting the spatial variation of the chemical composition of lake waters in the Tatra Mountains. In most cases, the lake waters are acidic and very dilute, with a low ionic content and low conductivity values. In general, HCO3- is the predominant anion and Ca2+ is the predominant cation in the chemical composition of the analysed water samples. Among nutrients, NO3- is the dominant form of nitrogen, but also NH4+ may be found in lake waters. By using principal component analysis (PCA two factors have been identified that explain 63.6% of the variation in the chemical composition of water. Factor 1, which explains 43.2% of the total variability, is associated with Ca2+, SO42-, HCO3-, Na+, pH and lake area and is related to weathering and atmospheric deposition. Factor 2 explains 20.4% of the total variability and is associated with Mg2+, K+, Cl- and with lake altitude. In terms of chemical composition, based on the projection of cases of the first and second factor, the lakes in the Tatra Mountains may be divided into four groups, representing the following: lakes situated within the subalpine forest at the lowest altitude (<1300 m a.s.l., characterized by medium mineralization (~14 mg dm-3 and the highest concentration of NH4+ and Cl- (Group I, 8 lakes; slightly alkaline lakes, with the lowest average acidification, medium mineralization (~31 mg dm-3 and the highest concentrations of Ca2+, Mg2+, Na+, K+, HCO3-, SO42-, and low concentrations of NO3- (Group II, 2 lakes; small lakes (<0.01 ha located within the alpine meadow and the nival zones at high elevations with the lowest mean mineralization (~4.3 mg dm-3, with the highest ammonium contribution to the sum of ions among all lakes and the largest sensitivity to acidification (Group III, 13 lakes; large lakes with high mineralization and slightly acidic pH (Group IV, 26 lakes and medium mineralization (~31 mg dm-3.

  14. Selective Pressure along a Latitudinal Gradient Affects Subindividual Variation in Plants

    Science.gov (United States)

    Sobral, Mar; Guitián, José; Guitián, Pablo; Larrinaga, Asier R.

    2013-01-01

    Individual plants produce repeated structures such as leaves, flowers or fruits, which, although belonging to the same genotype, are not phenotypically identical. Such subindividual variation reflects the potential of individual genotypes to vary with micro-environmental conditions. Furthermore, variation in organ traits imposes costs to foraging animals such as time, energy and increased predation risk. Therefore, animals that interact with plants may respond to this variation and affect plant fitness. Thus, phenotypic variation within an individual plant could be, in part, an adaptive trait. Here we investigated this idea and we found that subindividual variation of fruit size of Crataegus monogyna, in different populations throughout the latitudinal gradient in Europe, was explained at some extent by the selective pressures exerted by seed-dispersing birds. These findings support the hypothesis that within-individual variation in plants is an adaptive trait selected by interacting animals which may have important implications for plant evolution. PMID:24069297

  15. Chemical composition, antioxidant and antimicrobial activities of basil (Ocimum basilicum) essential oils depends on seasonal variations.

    Science.gov (United States)

    Hussain, Abdullah Ijaz; Anwar, Farooq; Hussain Sherazi, Syed Tufail; Przybylski, Roman

    2008-06-01

    Chemical composition, antioxidant and antimicrobial activities of the essential oils from aerial parts of basil (Ocimum basilicum L.) as affected by four seasonal, namely summer, autumn, winter and spring growing variation were investigated. The hydro-distilled essential oils content ranged from 0.5% to 0.8%, the maximum amounts were observed in winter while minimum in summer. The essential oils consisted of linalool as the most abundant component (56.7-60.6%), followed by epi-α-cadinol (8.6-11.4%), α-bergamotene (7.4-9.2%) and γ-cadinene (3.2-5.4%). Samples collected in winter were found to be richer in oxygenated monoterpenes (68.9%), while those of summer were higher in sesquiterpene hydrocarbons (24.3%). The contents of most of the chemical constituents varied significantly (p<0.05) with different seasons. The essential oils investigated, exhibited good antioxidant activity as measurements by DPPH free radical-scavenging ability, bleaching β-carotene in linoleic acid system and inhibition of linoleic acid oxidation. Evaluation of antimicrobial activity of the essential oils and linalool, the most abundant component, against bacterial strains: Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Pasteurella multocida and pathogenic fungi Aspergillus niger, Mucor mucedo, Fusarium solani, Botryodiplodia theobromae, Rhizopus solani was assessed by disc diffusion method and measurement of determination of minimum inhibitory concentration. The results of antimicrobial assays indicated that all the tested microorganisms were affected. Both the antioxidant and antimicrobial activities of the oils varied significantly (p<0.05), as seasons changed. Copyright © 2007 Elsevier Ltd. All rights reserved.

  16. Chemical factors affecting fission product transport in severe LMFBR accidents

    Energy Technology Data Exchange (ETDEWEB)

    Wichner, R.P.; Jolley, R.L.; Gat, U.; Rodgers, B.R.

    1984-10-01

    This study was performed as a part of a larger evaluation effort on LMFBR accident, source-term estimation. Purpose was to provide basic chemical information regarding fission product, sodium coolant, and structural material interactions required to perform estimation of fission product transport under LMFBR accident conditions. Emphasis was placed on conditions within the reactor vessel; containment vessel conditions are discussed only briefly.

  17. 15 CFR 710.4 - Overview of scheduled chemicals and examples of affected industries.

    Science.gov (United States)

    2010-01-01

    ... Commerce and Foreign Trade (Continued) BUREAU OF INDUSTRY AND SECURITY, DEPARTMENT OF COMMERCE CHEMICAL... REGULATIONS (CWCR) § 710.4 Overview of scheduled chemicals and examples of affected industries. The following... 15 Commerce and Foreign Trade 2 2010-01-01 2010-01-01 false Overview of scheduled chemicals and...

  18. Variation of Chemical Elements and their Associations in Laterite Soil Profile

    Directory of Open Access Journals (Sweden)

    M Tufaila

    2015-05-01

    Full Text Available The objective of this study was to evaluate the variations of twelve chemical elements (Ni, Fe, Co, Mg, Mn, Al, Si, Zn, Ti, P, Ca and Cr in laterite soil profiles from Wantulasi area in South East Sulawesi Province of Indonesia. Eighty four (84 samples of three profiles (i.e. each profile consists of eight samples had been used to study their variations in soil using the X-Ray Fluorescence (XRF. Results analysis of the chemical elements content in three profile using XRF indicated that there were good correlationsbetween the chemical elements in the soil profile with the significant correlations were found in Ni and Fe, Ni and Si, Ti and P, Fe and Al, and Co and Mn, respectively. On the other hand,the results of study showed that the variations of the chemical elements could be related to the enrichment and translocation of the elements in soil profile and also their possibilities to be related with a given chemical elements in soil profile. Therefore, we suggest that the observed patterns in chemical elements with a good correlation in laterite profile can be used as proxies to integrate the evaluation of the chemical and physical weathering process based on the elements characteristics in soil profiles.

  19. Variations in chemical sexual signals of Psammodromus algirus lizards along an elevation gradient may reflect altitudinal variation in microclimatic conditions

    Science.gov (United States)

    Martín, José; Javier Zamora-Camacho, Francisco; Reguera, Senda; López, Pilar; Moreno-Rueda, Gregorio

    2017-04-01

    Chemical signals used in intraspecific communication are expected to evolve or to show phenotipic plasticity to maximize efficacy in the climatic conditions of a given environment. Elevational environmental gradients in mountains provide a good opportunity to test this hypothesis by examining variation in characteristics of signals in species found across different elevations with different climatic conditions. We analyzed by gas chromatography-mass spectrometry (GC-MS) the lipophilic fraction of the femoral gland secretions of male lizards Psammodromus algirus (Fam. Lacertidae) from six localities located along a 2200 m elevational gradient at Sierra Nevada Mountains (SE Spain). There was elevational clinal variation in climatic variables, number of femoral pores and in the relative proportions of some classes of compounds (i.e., ethyl esters of fatty acids, waxy esters, and aldehydes) but not others. We discuss how this variation would result in different physicochemical properties of the entire femoral secretion, which might help optimize the efficacy of chemical signals under the particular microclimatic conditions at each elevation.

  20. Variation of Chemical Elements and their Associations in Laterite Soil Profile

    OpenAIRE

    M Tufaila; La Ode Safiuddin; Rosliana Eso; Sitti Kasmiati; Hasbullah Syaf; La Ode Ahmad Nur Ramadhan; Hasrorayan; Ardin

    2015-01-01

    The objective of this study was to evaluate the variations of twelve chemical elements (Ni, Fe, Co, Mg, Mn, Al, Si, Zn, Ti, P, Ca and Cr) in laterite soil profiles from Wantulasi area in South East Sulawesi Province of Indonesia. Eighty four (84) samples of three profiles (i.e. each profile consists of eight samples) had been used to study their variations in soil using the X-Ray Fluorescence (XRF). Results analysis of the chemical elements content in three profile using XRF indicated that t...

  1. Variation of Chemical Elements and Their Associations in Laterite Soil Profile

    OpenAIRE

    M Tufaila; La Ode Safiuddin; Rosliana Eso; Sitti Kasmiati; Hasbullah Syaf; La Ode Ahmad Nur Ramadhan; Hasrorayan; Ardin

    2015-01-01

    The objective of this study was to evaluate the variations of twelve chemical elements (Ni, Fe, Co, Mg, Mn, Al, Si, Zn, Ti, P, Ca and Cr) in laterite soil profiles from Wantulasi area in South East Sulawesi Province of Indonesia. Eighty four (84) samples of three profiles (i.e. each profile consists of eight samples) had been used to study their variations in soil using  the X-Ray Fluorescence (XRF). Results analysis of the chemical elements content in three profile using XRF indicated t...

  2. Genetic variation, inbreeding and chemical exposure—combined effects in wildlife and critical considerations for ecotoxicology

    Science.gov (United States)

    Brown, A. Ross; Hosken, David J.; Balloux, François; Bickley, Lisa K.; LePage, Gareth; Owen, Stewart F.; Hetheridge, Malcolm J.; Tyler, Charles R.

    2009-01-01

    Exposure to environmental chemicals can have negative consequences for wildlife and even cause localized population extinctions. Resistance to chemical stress, however, can evolve and the mechanisms include desensitized target sites, reduced chemical uptake and increased metabolic detoxification and sequestration. Chemical resistance in wildlife populations can also arise independently of exposure and may be spread by gene flow between populations. Inbreeding—matings between closely related individuals—can have negative fitness consequences for natural populations, and there is evidence of inbreeding depression in many wildlife populations. In some cases, reduced fitness in inbred populations has been shown to be exacerbated under chemical stress. In chemical testing, both inbred and outbred laboratory animals are used and for human safety assessments, iso-genic strains (virtual clones) of mice and rats are often employed that reduce response variation, the number of animals used and associated costs. In contrast, for environmental risk assessment, strains of animals are often used that have been selectively bred to maintain heterozygosity, with the assumption that they are better able to predict adverse effects in wild, genetically variable, animals. This may not necessarily be the case however, as one outbred strain may not be representative of another or of a wild population. In this paper, we critically discuss relationships between genetic variation, inbreeding and chemical effects with the intention of seeking to support more effective chemical testing for the protection of wildlife. PMID:19833649

  3. Evaluating the Genetic, Hormonal, and Exogenous Factors Affecting Somatic Copy Number Variation in Breast Cancer

    Science.gov (United States)

    2016-10-01

    AWARD NUMBER: W81XWH-15-1-0579 TITLE: Evaluating the Genetic , Hormonal, and Exogenous Factors Affecting Somatic Copy Number Variation in...Sep 2015 - 29 Sep 2016 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Evaluating the Genetic , Hormonal, and Exogenous Factors Affecting Somatic Copy...progress in subaim 1a, substantially improving the design of our proposed transgenic animal , the “deletion reporter mouse”, and are finalizing cloning

  4. Biochar physico-chemical properties as affected by environmental exposure

    Energy Technology Data Exchange (ETDEWEB)

    Sorrenti, Giovambattista, E-mail: g.sorrenti@unibo.it [Department of Agricultural Sciences, University of Bologna, viale G. Fanin 44, 40127 Bologna (Italy); Masiello, Caroline A., E-mail: masiello@rice.edu [Departments of Earth Science, BioSciences, and Chemistry, Rice University, Houston, TX 77005 (United States); Dugan, Brandon, E-mail: dugan@rice.edu [Department of Earth Science, Rice University, Houston, TX 77005 (United States); Toselli, Moreno, E-mail: moreno.toselli@unibo.it [Department of Agricultural Sciences, University of Bologna, viale G. Fanin 44, 40127 Bologna (Italy)

    2016-09-01

    To best use biochar as a sustainable soil management and carbon (C) sequestration technique, we must understand the effect of environmental exposure on its physical and chemical properties because they likely vary with time. These properties play an important role in biochar's environmental behavior and delivery of ecosystem services. We measured biochar before amendment and four years after amendment to a commercial nectarine orchard at rates of 5, 15 and 30 t ha{sup −1}. We combined two pycnometry techniques to measure skeletal (ρ{sub s}) and envelope (ρ{sub e}) density and to estimate the total pore volume of biochar particles. We also examined imbibition, which can provide information about soil hydraulic conductivity. Finally, we investigated the chemical properties, surface, inner layers atomic composition and C1s bonding state of biochar fragments through X-ray photoelectron spectroscopy (XPS). Ageing increased biochar skeletal density and reduced the water imbibition rate within fragments as a consequence of partial pore clogging. However, porosity and the volume of water stored in particles remained unchanged. Exposure reduced biochar pH, EC, and total C, but enhanced total N, nitrate-N, and ammonium-N. X-ray photoelectron spectroscopy analyses showed an increase of O, Si, N, Na, Al, Ca, Mn, and Fe surface (0–5 nm) atomic composition (at%) and a reduction of C and K in aged particles, confirming the interactions of biochar with soil inorganic and organic phases. Oxidation of aged biochar fragments occurred mainly in the particle surface, and progressively decreased down to 75 nm. Biochar surface chemistry changes included the development of carbonyl and carboxylate functional groups, again mainly on the particle surface. However, changes were noticeable down to 75 nm, while no significant changes were measured in the deepest layer, up to 110 nm. Results show unequivocal shifts in biochar physical and chemical properties/characteristics over

  5. Meta-Analysis of the Chemical and Non-Chemical Stressors Affecting Childhood Obesity

    Science.gov (United States)

    Worldwide, approximately 42 million children under the age of 5 years are considered overweight or obese. While much research has focused on individual behaviors impacting obesity, little research has emphasized the complex interactions of numerous chemical and non-chemical stres...

  6. Genomic Copy Number Variation Affecting Genes Involved in the Cell Cycle Pathway: Implications for Somatic Mosaicism

    Directory of Open Access Journals (Sweden)

    Ivan Y. Iourov

    2015-01-01

    Full Text Available Somatic genome variations (mosaicism seem to represent a common mechanism for human intercellular/interindividual diversity in health and disease. However, origins and mechanisms of somatic mosaicism remain a matter of conjecture. Recently, it has been hypothesized that zygotic genomic variation naturally occurring in humans is likely to predispose to nonheritable genetic changes (aneuploidy acquired during the lifetime through affecting cell cycle regulation, genome stability maintenance, and related pathways. Here, we have evaluated genomic copy number variation (CNV in genes implicated in the cell cycle pathway (according to Kyoto Encyclopedia of Genes and Genomes/KEGG within a cohort of patients with intellectual disability, autism, and/or epilepsy, in which the phenotype was not associated with genomic rearrangements altering this pathway. Benign CNVs affecting 20 genes of the cell cycle pathway were detected in 161 out of 255 patients (71.6%. Among them, 62 individuals exhibited >2 CNVs affecting the cell cycle pathway. Taking into account the number of individuals demonstrating CNV of these genes, a support for this hypothesis appears to be presented. Accordingly, we speculate that further studies of CNV burden across the genes implicated in related pathways might clarify whether zygotic genomic variation generates somatic mosaicism in health and disease.

  7. Chemical characteristics of precipitation in NH 3-affected areas

    Science.gov (United States)

    Schuurkes, J. A. A. R.; Maenen, M. M. J.; Roelofs, J. G. M.

    Effects of gaseous ammonia (NH 3) on precipitation chemistry were studied in four areas with a significant emission density as a result of animal manure production by intensive stockbreeding activities. In these NH 3-affected areas the quantity of ammonium (NH 4+) and sulphate (SO 42-) in atmospheric precipitation was 1.5-4 times higher than in relatively remote areas, whereas 70-90% of the deposition of nitrogen consisted of NHx compounds. Particularly within a distance of 1 km downwind point-sources of NH 3 emission bulk precipitation was less acidic and showed enhanced concentrations of NH 4 and SO 42- than at larger distances. NH 3 is the dominant agent which reacts with, and neutralizes, acid compounds in the atmosphere by forming (NH 4) 2SO 4. Annual mean volume-weighted concentrations of NH 4+ reached values of 179-369 μmol ℓ -1 those of SO 42- were 90-145 μmol ℓ -1. The highest measured total amount of NHx compounds deposited on an open water surface was 62 kg N ha -1 a -1. In the studied areas NH 4+ is the dominant form of N in atmospheric precipitation which, together with SO 42-, falls on and enters the biosphere.

  8. Mycobacterium tuberculosis Complex Exhibits Lineage-Specific Variations Affecting Protein Ductility and Epitope Recognition

    Science.gov (United States)

    Yruela, Inmaculada; Contreras-Moreira, Bruno; Magalhães, Carlos; Osório, Nuno S.

    2016-01-01

    Abstract The advent of whole-genome sequencing has provided an unprecedented detail about the evolution and genetic significance of species-specific variations across the whole Mycobacterium tuberculosis Complex. However, little attention has been focused on understanding the functional roles of these variations in the protein coding sequences. In this work, we compare the coding sequences from 74 sequenced mycobacterial species including M. africanum, M. bovis, M. canettii, M. caprae, M. orygis, and M. tuberculosis. Results show that albeit protein variations affect all functional classes, those proteins involved in lipid and intermediary metabolism and respiration have accumulated mutations during evolution. To understand the impact of these mutations on protein functionality, we explored their implications on protein ductility/disorder, a yet unexplored feature of mycobacterial proteomes. In agreement with previous studies, we found that a Gly71Ile substitution in the PhoPR virulence system severely affects the ductility of its nearby region in M. africanum and animal-adapted species. In the same line of evidence, the SmtB transcriptional regulator shows amino acid variations specific to the Beijing lineage, which affects the flexibility of the N-terminal trans-activation domain. Furthermore, despite the fact that MTBC epitopes are evolutionary hyperconserved, we identify strain- and lineage-specific amino acid mutations affecting previously known T-cell epitopes such as EsxH and FbpA (Ag85A). Interestingly, in silico studies reveal that these variations result in differential interaction of epitopes with the main HLA haplogroups. PMID:28062754

  9. 40 CFR 60.489a - List of chemicals produced by affected facilities.

    Science.gov (United States)

    2010-07-01

    ... facilities. Process units that produce, as intermediates or final products, chemicals listed in § 60.489 are... 40 Protection of Environment 6 2010-07-01 2010-07-01 false List of chemicals produced by affected facilities. 60.489a Section 60.489a Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR...

  10. Some chemical components of garden egg as affected by stage of ...

    African Journals Online (AJOL)

    ... chemical components at 0.05 confidence level. The interaction of fruit ripeness and storage temperature had the least significant influence on the tested parameters. The least affected parameter was the pH value. Key words: Chemical components; garden egg; ripeness; storage. Moor Journal of Agricultural Research ...

  11. Meta-Analysis of the Chemical and Non-Chemical Stressors Affecting Childhood Obesity?

    Science.gov (United States)

    Background: Worldwide, approximately 42 million children under the age of 5 years are considered overweight or obese. While much research has focused on individual behaviors impacting obesity, little research has emphasized the complex interactions of numerous chemical and non-ch...

  12. Variations in the Availability of Pollen Resources Affect Honey Bee Health.

    Directory of Open Access Journals (Sweden)

    Garance Di Pasquale

    Full Text Available Intensive agricultural systems often expose honey bees (Apis mellifera L. to large temporal variations in the availability (quantity, quality and diversity of nutritional resources. Such nutritional irregularity is expected to affect honey bee health. We therefore tested under laboratory conditions the effect of such variation in pollen availability on honey bee health (survival and nursing physiology-hypopharyngeal gland development and vitellogenin expression. We fed honey bees with different diets composed of pollen pellets collected by honey bees in an agricultural landscape of western France. Slight drops (5-10% in the availability of oilseed rape (Brassica napus L. pollen resulted in significant reductions of all tested variables. Despite some variations in taxonomic diversity and nutritional quality, the pollen mixes harvested over the season had a similar positive influence on honey bee health, except for the one collected in late July that induced poor survival and nursing physiology. This period coincided with the mass-flowering of maize (Zea mays L., an anemophilous crop which produces poor-quality pollen. Therefore, changes in bee health were not connected to variations in pollen diversity but rather to variations in pollen depletion and quality, such as can be encountered in an intensive agricultural system of western France. Finally, even though pollen can be available ad libitum during the mass-flowering of some crops (e.g. maize, it can fail to provide bees with diet adequate for their development.

  13. Variations in the Availability of Pollen Resources Affect Honey Bee Health.

    Science.gov (United States)

    Di Pasquale, Garance; Alaux, Cédric; Le Conte, Yves; Odoux, Jean-François; Pioz, Maryline; Vaissière, Bernard E; Belzunces, Luc P; Decourtye, Axel

    2016-01-01

    Intensive agricultural systems often expose honey bees (Apis mellifera L.) to large temporal variations in the availability (quantity, quality and diversity) of nutritional resources. Such nutritional irregularity is expected to affect honey bee health. We therefore tested under laboratory conditions the effect of such variation in pollen availability on honey bee health (survival and nursing physiology-hypopharyngeal gland development and vitellogenin expression). We fed honey bees with different diets composed of pollen pellets collected by honey bees in an agricultural landscape of western France. Slight drops (5-10%) in the availability of oilseed rape (Brassica napus L.) pollen resulted in significant reductions of all tested variables. Despite some variations in taxonomic diversity and nutritional quality, the pollen mixes harvested over the season had a similar positive influence on honey bee health, except for the one collected in late July that induced poor survival and nursing physiology. This period coincided with the mass-flowering of maize (Zea mays L.), an anemophilous crop which produces poor-quality pollen. Therefore, changes in bee health were not connected to variations in pollen diversity but rather to variations in pollen depletion and quality, such as can be encountered in an intensive agricultural system of western France. Finally, even though pollen can be available ad libitum during the mass-flowering of some crops (e.g. maize), it can fail to provide bees with diet adequate for their development.

  14. Inter-individual variation in vertebral kinematics affects predictions of neck musculoskeletal models.

    Science.gov (United States)

    Nevins, Derek D; Zheng, Liying; Vasavada, Anita N

    2014-10-17

    Experimental studies have found significant variation in cervical intervertebral kinematics (IVK) among healthy subjects, but the effect of this variation on biomechanical properties, such as neck strength, has not been explored. The goal of this study was to quantify variation in model predictions of extension strength, flexion strength and gravitational demand (the ratio of gravitational load from the weight of the head to neck muscle extension strength), due to inter-subject variation in IVK. IVK were measured from sagittal radiographs of 24 subjects (14F, 10M) in five postures: maximal extension, mid-extension, neutral, mid-flexion, and maximal flexion. IVK were defined by the position (anterior-posterior and superior-inferior) of each cervical vertebra with respect to T1 and its angle with respect to horizontal, and fit with a cubic polynomial over the range of motion. The IVK of each subject were scaled and incorporated into musculoskeletal models to create models that were identical in muscle force- and moment-generating properties but had subject-specific kinematics. The effect of inter-subject variation in IVK was quantified using the coefficient of variation (COV), the ratio of the standard deviation to the mean. COV of extension strength ranged from 8% to 15% over the range of motion, but COV of flexion strength was 20-80%. Moreover, the COV of gravitational demand was 80-90%, because the gravitational demand is affected by head position as well as neck strength. These results indicate that including inter-individual variation in models is important for evaluating neck musculoskeletal biomechanical properties. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. COMT genetic variation confers risk for psychotic and affective disorders: a case control study

    Directory of Open Access Journals (Sweden)

    Lencz Todd

    2005-10-01

    Full Text Available Abstract Background Variation in the COMT gene has been implicated in a number of psychiatric disorders, including psychotic, affective and anxiety disorders. The majority of these studies have focused on the functional Val108/158Met polymorphism and yielded conflicting results, with limited studies examining the relationship between other polymorphisms, or haplotypes, and psychiatric illness. We hypothesized that COMT variation may confer a general risk for psychiatric disorders and have genotyped four COMT variants (Val158Met, rs737865, rs165599, and a SNP in the P2 promoter [-278A/G; rs2097603] in 394 Caucasian cases and 467 controls. Cases included patients with schizophrenia (n = 196, schizoaffective disorder (n = 62, bipolar disorder (n = 82, major depression (n = 30, and patients diagnosed with either psychotic disorder NOS or depressive disorder NOS (n = 24. Results SNP rs2097603, the Val/Met variant and SNP rs165599 were significantly associated (p = 0.004; p = 0.05; p = 0.035 with a broad "all affected" diagnosis. Haplotype analysis revealed a potentially protective G-A-A-A haplotype haplotype (-278A/G; rs737865; Val108/158Met; rs165599, which was significantly underrepresented in this group (p = 0.0033 and contained the opposite alleles of the risk haplotype previously described by Shifman et al. Analysis of diagnostic subgroups within the "all affecteds group" showed an association of COMT in patients with psychotic disorders as well as in cases with affective illness although the associated variants differed. The protective haplotype remained significantly underrepresented in most of these subgroups. Conclusion Our results support the view that COMT variation provides a weak general predisposition to neuropsychiatric disease including psychotic and affective disorders.

  16. Variations in Aerosol Chemical Composition during New Particle Formation and Growth Events Downwind of Seoul, Korea

    Science.gov (United States)

    Park, J.; Choi, Y.; Ghim, Y. S.

    2016-12-01

    New particle formation and growth has been characterized through various field studies using scanning mobility particle sizer (SMPS). However, there is insufficient knowledge of the variation of aerosol chemical compositions during those events. We investigated the variation of aerosol chemical composition during new particle formation and growth events downwind of Seoul. New particle formation and growth events were identified based on the evolution of the number size distribution measured by SMPS. The concentrations of inorganic ions and black carbon were measured using a particle-into-liquid sampler (PILS) coupled with an ion chromatograph (IC) and multi-angle absorption photometer (MAAP), respectively. We also measured concentrations of gaseous precursors (SO2, NO2) along with meteorological parameters using an automatic weather station. The measurements were conducted on the rooftop of a five-story building on a hill (37.34°N, 127.27°E, 167 m above sea level) at the Global Campus of Hankuk University of Foreign Studies, located about 35 km southeast of downtown Seoul. The measurement periods were from February 12 to April 1, 2015 and from April 13 to June 12, 2016. We investigated the difference in chemical compositions between event and non-event days and its association with the variations in precursor concentrations and meteorological parameters.

  17. Effects of crystallinity and chemical variation on apparent band-gap shift in polycrystalline indium nitride

    Energy Technology Data Exchange (ETDEWEB)

    Chen, P.P.-T., E-mail: patrick.chen@mq.edu.a [Department of Physics and Astronomy, Faculty of Science, Macquarie University, Sydney, NSW 2109 (Australia); Downes, J.E.; Fernandes, A.J.; Butcher, K.S.A.; Wintrebert-Fouquet, M. [Department of Physics and Astronomy, Faculty of Science, Macquarie University, Sydney, NSW 2109 (Australia); Wuhrer, R.; Phillips, M.R. [Microstructural Analysis Unit, Faculty of Science, University of Technology, Sydney, Broadway, NSW 2007 (Australia)

    2011-01-03

    The nature of the apparent band-gap shift in polycrystalline indium nitride thin-films, grown by remote-plasma-enhanced chemical vapour deposition at 535 {+-} 10 {sup o}C, has been investigated separately in relation to growth temperature dependent crystallinity and chemical variation. Substrates of sapphire and gallium nitride on sapphire were used to study the effect of a stress-reduced template on indium nitride crystallite quality and apparent band-gap. To mimic surface growth temperature variations two glass substrates of differing thickness and thermal conductivity were intentionally used for the same growth conditions. The samples were characterised using optical transmission, scanning electron microscope, X-ray diffraction, and high-resolution X-ray photoelectron spectroscopy. The results indicate that the apparent band-gap shift in polycrystalline narrow band-gap indium nitride thin-films is not primarily determined by the quality of indium nitride crystallites but rather it is associated with growth temperature dependent chemical variations in the films.

  18. Variations in chemical and isotopic compositions of groundwaters from the Otobaru landslide in the area of hydrothermal alteration, Beppu City

    Energy Technology Data Exchange (ETDEWEB)

    Yoshioka, Ryuma; Kitaoka, Koichi; Kamiyama, Kokichi (Kyoto Univ., Uji (Japan). Disaster Prevention Research Inst.)

    1989-10-01

    The landslide at the Otobaru area, Beppu City, occurred twice in 1943 and 1969. A part of this area, even now, is affected considerably by thermal activities. Variations in chemical and isotopic compositions of waters from the Otobaru area and its vicinity were investigated from 1977 to 1983 and 1986 to 1987. The results are as follows: (1) electric conductivity data suggest that the two kinds of low-concentration water and high-concentration water exist in the landslide area, (2) the existence-of two groundwater aquifer in the landslide area and its vicinity is inferred from tritium data, (3) variations chemical composition of waters from the horizontal borehole are accompanied by the rise and decline of water table, (4) the waters from the landslide area and its vicinity are in equilibrium with montmorillonite, (5) the most waters under 10{sup -1} atm. of P{sub co2} are saturated or supersaturated with calcite, and (6) there is no detectable contribution of geothermal water to the waters from the landslide and its vicinity. And our hypothesis on the mechanism for the formation of calcium sulfate type water is also presented. (author).

  19. Molecular-level variation affects population growth in a butterfly metapopulation.

    Directory of Open Access Journals (Sweden)

    Ilkka Hanski

    2006-05-01

    Full Text Available The dynamics of natural populations are thought to be dominated by demographic and environmental processes with little influence of intraspecific genetic variation and natural selection, apart from inbreeding depression possibly reducing population growth in small populations. Here we analyse hundreds of well-characterised local populations in a large metapopulation of the Glanville fritillary butterfly (Melitaea cinxia, which persists in a balance between stochastic local extinctions and recolonisations in a network of 4,000 discrete habitat patches. We show that the allelic composition of the glycolytic enzyme phosphoglucose isomerase (Pgi has a significant effect on the growth of local populations, consistent with previously reported effects of allelic variation on flight metabolic performance and fecundity in the Glanville fritillary and Colias butterflies. The strength and the sign of the molecular effect on population growth are sensitive to the ecological context (the area and spatial connectivity of the habitat patches, which affects genotype-specific gene flow and the influence of migration on the dynamics of local populations. The biological significance of the results for Pgi is underscored by lack of any association between population growth and allelic variation at six other loci typed in the same material. In demonstrating, to our knowledge for the first time, that molecular variation in a candidate gene affects population growth, this study challenges the perception that differential performance of individual genotypes, leading to differential fitness, is irrelevant to population dynamics. These results also demonstrate that the spatial configuration of habitat and spatial dynamics of populations contribute to maintenance of Pgi polymorphism in this species.

  20. Chemical composition and seasonal variation of the volatile oils from Trembleya phlogiformis leaves

    Directory of Open Access Journals (Sweden)

    Sarah R. Fernandes

    Full Text Available ABSTRACT Trembleya phlogiformis DC., Melastomataceae, is a shrub whose leaves are used as a dye for dyeing wool and cotton. The present article aimed to carry out the morphological description of the species, to study the chemical composition of volatile oils from the leaves and flowers and the seasonal variability from the leaves during a year. Macroscopic characterization was carried out with the naked eye and with a stereoscopic microscope. Volatile oils were isolated by hydrodistillation in Clevenger apparatus and analyzed by gas chromatography/mass spectrometry. The major components of the volatile oil of T. phlogiformis flowers were: n-heneicosane (33.5%, phytol (12.3%, n-tricosane (8.4% and linoleic acid (6.1%. It was verified the existence of a large chemical variability of the volatile oils from the leaves of T. phlogiformis over the months, with the majority compound (oleic alcohol, ranging from 5.7 to 26.8% present in all samples. A combination of Cluster Analysis and Principal Component Analysis showed the existence of three main clusters, probably related to the seasons. The results suggested that the volatile oils of T. phlogiformis leaves possess high chemical variability, probably related to variation associated with rainfall and the variation in the behavior of specimens throughout the year. This research provides insights for future studies on the volatile oils obtained from the T. phlogiformis leaves and flowers, mainly related to biological markers of applications monitored in the leaves and flowers of this species.

  1. To What Extent Does DNA Methylation Affect Phenotypic Variation in Cattle?

    Directory of Open Access Journals (Sweden)

    Stephanie McKAY

    2015-07-01

    Full Text Available DNA methylation is an environmentally influenced epigenetic modification that regulates gene transcription and has the potential to influence variation in economically important phenotypes in agricultural species. We have utilized a novel approach to evaluate the relationship between genetic and epigenetic variation and downstream phenotypes. To begin with, we have integrated RNA-Seq and methyl binding domain sequencing (MBD-Seq data in order to determine the extent to which DNA methylation affects phenotypic variation in economically important traits of cattle. MBD-Seq is a technique that involves the sample enrichment of methylated genomic regions followed by their next-generation sequencing. This study utilized Illumina next generation sequencing technology to perform both RNA-Seq and MBD-Seq. NextGENe software (SoftGenetics, State College, PA was employed for quality trimming and aligning the sequence reads to the UMD3.1 bovine reference genome, generating counts of matched reads and methylated peak identification. Subsequently, we identified and quantified genome-wide methylated regions and characterized the extent of differential methylation and differential expression between two groups of animals with extreme phenotypes. The program edgeR from the R software package (version 3.0.1 was employed for identifying differentially methylated regions and regions of differential expression. Finally, Partial Correlation with Information Theory (PCIT was performed to identify transcripts and methylation events that exhibit differential hubbing. A differential hub is defined as a gene network hub that is more highly connected in one treatment group than the other. This analysis produced every possible pair-wise interaction that subsequently enabled us to look at network interactions of how methylation affects expression. (co-expression, co-methylation, methylation x expression. Genomic regions of interest derived from this analysis were then aligned

  2. The role of tributary mixing in chemical variations at a karst spring, Milandre, Switzerland

    Science.gov (United States)

    Perrin, J.; Jeannin, P.-Y.; Cornaton, F.

    2007-01-01

    SummarySolute concentration variations during flood events were investigated in a karst aquifer of the Swiss Jura. Observations were made at the spring, and at the three main subterraneous tributaries feeding the spring. A simple transient flow and transport numerical model was able to reproduce chemographs and hydrographs observed at the spring, as a result of a mixing of the concentration and discharge of the respective tributaries. Sensitivity analysis carried out with the model showed that it is possible to produce chemical variations at the spring even if all tributaries have constant (but different for each of them) solute concentrations. This process is called tributary mixing. The good match between observed and modelled curves indicate that, in the phreatic zone, tributary mixing is probably an important process that shapes spring chemographs. Chemical reactions and other mixing components (e.g. from low permeability volumes) have a limited influence. Dissolution-related (calcium, bicarbonate, specific conductance) and pollution-related parameters (nitrate, chloride, potassium) displayed slightly different behaviours: during moderate flood events, the former showed limited variations compared to the latter. During large flood events, both presented chemographs with significant changes. No significant event water participates in moderate flood events and tributary mixing will be the major process shaping chemographs. Variations are greater for parameters with higher spatial variability (e.g. pollution-related). Whereas for large flood events, the contribution of event water becomes significant and influences the chemographs of all the parameters. As a result, spring water vulnerability to an accidental pollution is low during moderate flood events and under base flow conditions. It strongly increases during large flood events, because event water contributes to the spring discharge.

  3. Variation in Miscanthus chemical composition and implications for conversion by pyrolysis and thermo-chemical bio-refining for fuels and chemicals.

    Science.gov (United States)

    Hodgson, E M; Nowakowski, D J; Shield, I; Riche, A; Bridgwater, A V; Clifton-Brown, J C; Donnison, I S

    2011-02-01

    Different species and genotypes of Miscanthus were analysed to determine the influence of genotypic variation and harvest time on cell wall composition and the products which may be refined via pyrolysis. Wet chemical, thermo-gravimetric (TGA) and pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS) methods were used to identify the main pyrolysis products and determine the extent to which genotypic differences in cell wall composition influence the range and yield of pyrolysis products. Significant genotypic variation in composition was identified between species and genotypes, and a clear relationship was observed between the biomass composition, yields of pyrolysis products, and the composition of the volatile fraction. Results indicated that genotypes other than the commercially cultivated Miscanthus x giganteus may have greater potential for use in bio-refining of fuels and chemicals and several genotypes were identified as excellent candidates for the generation of genetic mapping families and the breeding of new genotypes with improved conversion quality characteristics. Copyright © 2010 Elsevier Ltd. All rights reserved.

  4. Essential oil variation in wild populations of Artemisia saharae (Asteraceae) from Tunisia: chemical composition, antibacterial and antioxidant properties.

    Science.gov (United States)

    Zouari, Sami; Ayadi, Imen; Fakhfakh, Nahed; Jdir, Hamida; Aloui, Latifa; Kossentini, Mohamed; Rebai, Ahmed; Zouari, Nacim

    2014-12-01

    Artemisia saharae Pomel is a new taxon of Artemisia herba-alba Asso (Asteraceae) which is endemic to Tunisia and Algeria. This shrub, commonly known as white wormwood or desert wormwood, is largely used in folk medicine and as a culinary herb. The bulks aromatic plants come from wild populations whose essential oils compositions as well as their biological properties are severely affected by several factors such as geographic conditions. Therefore, the aim of the present work is to provide more information about the influence of altitude variation on the essential oil composition, antimicrobial and antioxidant properties of Artemisia saharae growing wild in the same geographical area. Essential oils were extracted by hydrodistillation of leaves and flowers of the plant collected from seven different altitudes of the Baten Zamour region (southwest of Tunisia). The highest essential oil yields (2.70-2.80%) were obtained for populations of high altitudes. Seventy-five compounds, representing 92.78 to 96.95% of the total essential oils, were separated and identified. Essential oils were characterized by very high percentage of oxygenated monoterpenes (52.1-72.6%) which constituted the predominant class. From the analyzed populations, the major compounds (>7%) were α-thujone, β-thujone, chrysanthenone, camphor, chrysanthenyl acetate, and sabinyl acetate. Sabinyl acetate which was detected in some populations at relatively high percentages (7.7-10.8%) seems to be characteristic to Southern Tunisian A. saharae. The studied essential oil showed a chemical diversity depending on the population altitude as revealed by linear discriminant and cluster analyses. Three population groups associated with altitudinal levels were distinguished. It is worthy to note that the most discriminating compounds of chemical groups were the minor ones. Despite the high variation of essential oil compositions, the high altitude population did not affect severely the antibacterial activity

  5. Experimental parasite community ecology: intraspecific variation in a large tapeworm affects community assembly.

    Science.gov (United States)

    Benesh, Daniel P; Kalbe, Martin

    2016-07-01

    Non-random species associations occur in naturally sampled parasite communities. The processes resulting in predictable community structure (e.g. particular host behaviours, cross-immunity, interspecific competition) could be affected by traits that vary within a parasite species, like growth or antigenicity. We experimentally infected three-spined sticklebacks with a large tapeworm (Schistocephalus solidus) that impacts the energy needs, foraging behaviour and immune reactions of its host. The tapeworms came from two populations, characterized by high or low growth in sticklebacks. Our goal was to evaluate how this parasite, and variation in its growth, affects the acquisition of other parasites. Fish infected with S. solidus were placed into cages in a lake to expose them to the natural parasite community. We also performed a laboratory experiment in which infected fish were exposed to a fixed dose of a common trematode parasite. In the field experiment, infection with S. solidus affected the abundance of four parasite species, relative to controls. For two of the four species, changes occurred only in fish harbouring the high-growth S. solidus; one species increased in abundance and the other decreased. These changes did not appear to be directly linked to S. solidus growth though. The parasite exhibiting elevated abundance was the same trematode used in the laboratory infection. In that experiment, we found a similar infection pattern, suggesting that S. solidus affects the physiological susceptibility of fish to this trematode. Associations between S. solidus and other parasites occur and vary in direction. However, some of these associations were contingent on the S. solidus population, suggesting that intraspecific variability can affect the assembly of parasite communities. © 2016 The Authors. Journal of Animal Ecology © 2016 British Ecological Society.

  6. Institutional Viability Of The Cooperative In Northern Samar And The Variates Affecting It

    Directory of Open Access Journals (Sweden)

    Farah Alo Mdulid

    2015-08-01

    Full Text Available Abstract This study attempted to find out the institutional viability of cooperatives in Northern Samar in terms of profitability liquidity and the variates affecting its viability. Thirty-three 33 registered primary cooperatives were the respondents. It adopted descriptive-evaluative research with multiple regression analysis in testing the relationship of the variables. Findings showed that 15 or 45 percent of the primary cooperatives were viable while 18 or 55 percent were not viable in terms of profitability. In terms of liquidity 28 or 85 percent were viable while 5 or 15 percent were non-viable. Results also revealed that the number of years of operation the number of employees and staff the rate of loan repayments and the amount of current authorized share capital significantly affected the viability of Cooperatives. Generally Cooperatives in Northern Samar are less profitable however majority of them are liquid which implies that the services are continuously rendered to the members. Specifically the finding suggests that the absence of participatory and collaborative management efforts of the members and the officials adversely affect the organizational financial viability. Key Words Institutional liquidity profitability. primary cooperativeratiovariates viability

  7. Interspecific variation in persistence of buried weed seeds follows trade-offs among physiological, chemical, and physical seed defenses.

    Science.gov (United States)

    Davis, Adam S; Fu, Xianhui; Schutte, Brian J; Berhow, Mark A; Dalling, James W

    2016-10-01

    Soil seedbanks drive infestations of annual weeds, yet weed management focuses largely on seedling mortality. As weed seedbanks increasingly become reservoirs of herbicide resistance, species-specific seedbank management approaches will be essential to weed control. However, the development of seedbank management strategies can only develop from an understanding of how seed traits affect persistence.We quantified interspecific trade-offs among physiological, chemical, and physical traits of weed seeds and their persistence in the soil seedbank in a common garden study. Seeds of 11 annual weed species were buried in Savoy, IL, from 2007 through 2012. Seedling recruitment was measured weekly and seed viability measured annually. Seed physiological (dormancy), chemical (phenolic compound diversity and concentration; invertebrate toxicity), and physical traits (seed coat mass, thickness, and rupture resistance) were measured.Seed half-life in the soil (t0.5) showed strong interspecific variation (F10,30 = 15, p weed seed dormancy and seedbank persistence are linked across diverse environments and agroecosystems. Moreover, among seedbank-forming early successional plant species, relative investment in chemical and physical seed defense varies with seedbank persistence. Synthesis and applications. Strong covariance among weed seed traits and persistence in the soil seedbank indicates potential for seedbank management practices tailored to specific weed species. In particular, species with high t0.5 values tend to invest less in chemical defenses. This makes them highly vulnerable to physical harvest weed seed control strategies, with small amounts of damage resulting in their full decay.

  8. Genetic variations in FSH action affect sex hormone levels and breast tissue size in infant girls

    DEFF Research Database (Denmark)

    Henriksen, Louise Scheutz; Hagen, Casper P; Assens, Maria

    2016-01-01

    , especially FSHR -29G>A and FSHR 2039A>G, affect female hormone profile and glandular breast tissue development already during minipuberty. Thus, genetic variations of FSH signaling appear to determine the individual set point of the hypothalamic-pituitary-gonadal axis already early in life.......Context: Single nucleotide polymorphisms altering FSH action (FSHB -211G>T, FSHR -29G>A, and FSHR 2039A>G) are associated with peripubertal and adult levels of reproductive hormones and age at pubertal onset in girls. Objective: To investigate whether genetic polymorphisms altering FSH action...... by PCR using Kompetitive Allele Specific PCR genotyping assays; identification of glandular breast tissue by palpation and measurement of the diameter. Serum levels of anti-Müllerian hormone, FSH, LH, estradiol, inhibin B, and sex hormone-binding globulin were assessed by immunoassays. Results: FSHR -29G...

  9. Natural selection affects multiple aspects of genetic variation at putatively neutral sites across the human genome.

    Science.gov (United States)

    Lohmueller, Kirk E; Albrechtsen, Anders; Li, Yingrui; Kim, Su Yeon; Korneliussen, Thorfinn; Vinckenbosch, Nicolas; Tian, Geng; Huerta-Sanchez, Emilia; Feder, Alison F; Grarup, Niels; Jørgensen, Torben; Jiang, Tao; Witte, Daniel R; Sandbæk, Annelli; Hellmann, Ines; Lauritzen, Torsten; Hansen, Torben; Pedersen, Oluf; Wang, Jun; Nielsen, Rasmus

    2011-10-01

    A major question in evolutionary biology is how natural selection has shaped patterns of genetic variation across the human genome. Previous work has documented a reduction in genetic diversity in regions of the genome with low recombination rates. However, it is unclear whether other summaries of genetic variation, like allele frequencies, are also correlated with recombination rate and whether these correlations can be explained solely by negative selection against deleterious mutations or whether positive selection acting on favorable alleles is also required. Here we attempt to address these questions by analyzing three different genome-wide resequencing datasets from European individuals. We document several significant correlations between different genomic features. In particular, we find that average minor allele frequency and diversity are reduced in regions of low recombination and that human diversity, human-chimp divergence, and average minor allele frequency are reduced near genes. Population genetic simulations show that either positive natural selection acting on favorable mutations or negative natural selection acting against deleterious mutations can explain these correlations. However, models with strong positive selection on nonsynonymous mutations and little negative selection predict a stronger negative correlation between neutral diversity and nonsynonymous divergence than observed in the actual data, supporting the importance of negative, rather than positive, selection throughout the genome. Further, we show that the widespread presence of weakly deleterious alleles, rather than a small number of strongly positively selected mutations, is responsible for the correlation between neutral genetic diversity and recombination rate. This work suggests that natural selection has affected multiple aspects of linked neutral variation throughout the human genome and that positive selection is not required to explain these observations.

  10. Evolutionary factors affecting Lactate dehydrogenase A and B variation in the Daphnia pulex species complex

    Directory of Open Access Journals (Sweden)

    Cristescu Melania E

    2011-07-01

    Full Text Available Abstract Background Evidence for historical, demographic and selective factors affecting enzyme evolution can be obtained by examining nucleotide sequence variation in candidate genes such as Lactate dehydrogenase (Ldh. Two closely related Daphnia species can be distinguished by their electrophoretic Ldh genotype and habitat. Daphnia pulex populations are fixed for the S allele and inhabit temporary ponds, while D. pulicaria populations are fixed for the F allele and inhabit large stratified lakes. One locus is detected in most allozyme surveys, but genome sequencing has revealed two genes, LdhA and LdhB. Results We sequenced both Ldh genes from 70 isolates of these two species from North America to determine if the association between Ldh genotype and habitat shows evidence for selection, and to elucidate the evolutionary history of the two genes. We found that alleles in the pond-dwelling D. pulex and in the lake-dwelling D. pulicaria form distinct groups at both loci, and the substitution of Glutamine (S for Glutamic acid (F at amino acid 229 likely causes the electrophoretic mobility shift in the LDHA protein. Nucleotide diversity in both Ldh genes is much lower in D. pulicaria than in D. pulex. Moreover, the lack of spatial structuring of the variation in both genes over a wide geographic area is consistent with a recent demographic expansion of lake populations. Neutrality tests indicate that both genes are under purifying selection, but the intensity is much stronger on LdhA. Conclusions Although lake-dwelling D. pulicaria hybridizes with the other lineages in the pulex species complex, it remains distinct ecologically and genetically. This ecological divergence, coupled with the intensity of purifying selection on LdhA and the strong association between its genotype and habitat, suggests that experimental studies would be useful to determine if variation in molecular function provides evidence that LDHA variants are adaptive.

  11. Increased Seasonal Variation in Serotonin Transporter Binding in Seasonal Affective Disorder.

    Science.gov (United States)

    Tyrer, Andrea E; Levitan, Robert D; Houle, Sylvain; Wilson, Alan A; Nobrega, José N; Meyer, Jeffrey H

    2016-09-01

    Seasonal affective disorder (SAD) is highly prevalent with rates of 1-6% and greater prevalence at more extreme latitudes; however, there are almost no direct brain investigations of this disorder. In health, serotonin transporter binding potential (5-HTT BPND), an index of 5-HTT levels, is greater throughout the brain in fall-winter compared with spring-summer. We hypothesized that in SAD, this seasonal variation would be greater in brain regions containing structures that regulate affect such as the prefrontal and anterior cingulate cortices (PFC and ACC). Furthermore, given the dimensional nature of SAD symptoms, it was hypothesized that seasonal fluctuation of 5-HTT BPND in the PFC and ACC would be greatest in severe SAD. Twenty SAD and twenty healthy participants underwent [(11)C]DASB positron emission tomography scans in summer and winter to measure seasonal variation in [(11)C]DASB 5-HTT BPND. Seasonal increases in [(11)C]DASB 5-HTT BPND were greater in SAD compared with healthy in the PFC and ACC, primarily due to differences between severe SAD and healthy (severe SAD vs healthy; Mann-Whitney U, U=42.5 and 37.0, p=0.005 and 0.003, respectively; greater magnitude in severe SAD of 35.10 and 14.23%, respectively), with similar findings observed in other regions (U=40.0-62.0, p=0.004-0.048; greater magnitude in severe SAD of 13.16-17.49%). To our knowledge, this is the first brain biomarker identified in SAD. This creates a new opportunity for phase 0 studies to target this phenotype and optimize novel prevention/treatment strategies for SAD.

  12. Variation of the strange-quark chemical potential in the phase diagram of nuclear matter

    CERN Document Server

    Panagiotou, A D; Gerodimou, E

    2002-01-01

    On the basis of lattice calculations, we require the existence of a deconfined quark matter region (0chemical potential is expressed in a functional form of the temperature and light-quark chemical potential and its variation throughout the 3-region phase diagram is studied. We propose the change of the sign of the strange-quark chemical potential, from positive in the hadronic region to negative beyond, to be a unique, concise and well-defined indication of the quark- deconfinement phase transition in nuclear matter. Analysis of the nucleus-nucleus collision data from AGS and SPS is presented giving strong support to our proposal. (23 refs).

  13. Chemical Cartography in the Milky Way with SDSS/APOGEE: Multi-element abundances and abundance ratio variations

    Science.gov (United States)

    Holtzman, Jon A.; Hasselquist, Sten; Johnson, Jennifer; Bird, Jonathan C.; Majewski, Steven R.; SDSS/APOGEE Team

    2017-01-01

    The SDSS/APOGEE project is measuring abundances of multiple elements for several hundred thousand stars across the Milky Way. These allow the mapping of abundances and abundance ratio variations. Results will be presented for multiple abundance ratios across of the Galactic disk. The interpretation of mean abundance maps is complicated by variations in star formation history across the disk and by changing abundance ratios that result from an overall metallicity gradient. Variations in chemical abundance sequences, however, show the potential for using abundance ratios to track the movement of stars through the disk, and provide key information for constraining Galaxy formation and chemical evolution models.

  14. Use of genotoxicity tests in a TIE to identify chemicals potentially affecting human health

    Energy Technology Data Exchange (ETDEWEB)

    Goudey, J.S. [HydroQual Labs. Ltd., Calgary, Alberta (Canada); Shaw, R.D.; Swanson, S.M. [Golder Associates Ltd., Calgary, Alberta (Canada); Nadeau, S. [Imperial Oil Resources Ltd., Calgary, Alberta (Canada)

    1995-12-31

    Imperial Oil operates a sour gas processing plant in southern Alberta that has, for the past several years, been the focus of considerable public and regulatory concern over perceived contamination of soils and groundwater on a nearby ranch. Elevated concentrations of DOC ({approximately}140 mg/L) have been received in groundwater underlying the plant site. Two process-related chemicals, sulfolane and diisopropanolamine (DIPA), had been previously identified as the primary components of the DOC plume, although the chemicals associated with 30% of the DOC could not be identified. A risk assessment was initiated in 1994 to determine whether off-site migration of sulfolane and DIPA or of other unidentified contaminants poses a risks to human health and/or ecological receptors. One component of the risk assessment included conducting a TIE to help identify the chemical(s) in contaminated groundwater underlying the gas plant that might adversely affect human health. Three endpoints were utilized in the TIE: MicroTox, SOS-Chromotest and the Ames test. MicroTox was used since it exhibited a response to whole groundwater from the site, while the genotoxicity tests were used because DIPA reportedly causes a response in the Ames test and because of the concern over potential human health affects arising from other unidentified contaminants. Results of the TIE indicated that the chemicals causing the toxicity in the groundwater sample were water soluble compounds, with similar characteristics to the process chemicals used at the gas plant and detected at high concentrations in groundwater from the plant site. These results provided additional evidence to help focus the risk assessment on the chemicals sulfolane and diisopropanolamine.

  15. Factors affecting spatial variation of annual apparent Q₁₀ of soil respiration in two warm temperate forests.

    Directory of Open Access Journals (Sweden)

    Junwei Luan

    Full Text Available A range of factors has been identified that affect the temperature sensitivity (Q₁₀ values of the soil-to-atmosphere CO₂ flux. However, the factors influencing the spatial distribution of Q₁₀ values within warm temperate forests are poorly understood. In this study, we examined the spatial variation of Q₁₀ values and its controlling factors in both a naturally regenerated oak forest (OF and a pine plantation (PP. Q₁₀ values were determined based on monthly soil respiration (R(S measurements at 35 subplots for each stand from Oct. 2008 to Oct. 2009. Large spatial variation of Q₁₀ values was found in both OF and PP, with their respective ranges from 1.7 to 5.12 and from 2.3 to 6.21. In PP, fine root biomass (FR (R = 0.50, P = 0.002, non-capillary porosity (NCP (R = 0.37, P = 0.03, and the coefficients of variation of soil temperature at 5 cm depth (CV of T₅ (R = -0.43, P = 0.01 well explained the spatial variance of Q₁₀. In OF, carbon pool lability reflected by light fractionation method (LLFOC well explained the spatial variance of Q₁₀ (R = -0.35, P = 0.04. Regardless of forest type, LLFOC and FR correlation with the Q₁₀ values were significant and marginally significant, respectively; suggesting a positive relationship between substrate availability and apparent Q₁₀ values. Parameters related to gas diffusion, such as average soil water content (SWC and NCP, negatively or positively explained the spatial variance of Q₁₀ values. Additionally, we observed significantly higher apparent Q₁₀ values in PP compared to OF, which might be partly attributed to the difference in soil moisture condition and diffusion ability, rather than different substrate availabilities between forests. Our results suggested that both soil chemical and physical characters contributed to the observed large Q₁₀ value variation.

  16. Foliar Nitrogen and Potassium Variation in Cottonwood as Affected by Genetic and Site Factors

    Science.gov (United States)

    James B. Baker; W. K. Randall

    1975-01-01

    Genetic and soil factors accounted for 49 percent of the variation in foliar N and 60 percent of the variation in foliar K among four good and four poor cottonwood clones grown on productive and unproductive soils in Mississippi. Variation in foliar N was associated primarily with the clone X soil interaction; variation in foliar K was related chiefly to clonal...

  17. Physico-chemical properties and cytotoxic effects of sugar-based surfactants: Impact of structural variations.

    Science.gov (United States)

    Lu, Biao; Vayssade, Muriel; Miao, Yong; Chagnault, Vincent; Grand, Eric; Wadouachi, Anne; Postel, Denis; Drelich, Audrey; Egles, Christophe; Pezron, Isabelle

    2016-09-01

    Surfactants derived from the biorefinery process can present interesting surface-active properties, low cytotoxicity, high biocompatibility and biodegradability. They are therefore considered as potential sustainable substitutes to currently used petroleum-based surfactants. To better understand and anticipate their performances, structure-property relationships need to be carefully investigated. For this reason, we applied a multidisciplinary approach to systematically explore the effect of subtle structural variations on both physico-chemical properties and biological effects. Four sugar-based surfactants, each with an eight carbon alkyl chain bound to a glucose or maltose head group by an amide linkage, were synthesized and evaluated together along with two commercially available standard surfactants. Physico-chemical properties including solubility, Krafft point, surface-tension lowering and critical micellar concentration (CMC) in water and biological medium were explored. Cytotoxicity evaluation by measuring proliferation index and metabolic activity against dermal fibroblasts showed that all surfactants studied may induce cell death at low concentrations (below their CMC). Results revealed significant differences in both physico-chemical properties and cytotoxic effects depending on molecule structural features, such as the position of the linkage on the sugar head-group, or the orientation of the amide linkage. Furthermore, the cytotoxic response increased with the reduction of surfactant CMC. This study underscores the relevance of a methodical and multidisciplinary approach that enables the consideration of surfactant solution properties when applied to biological materials. Overall, our results will contribute to a better understanding of the concomitant impact of surfactant structure at physico-chemical and biological levels. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Nitrogen addition affects chemical compositions of plant tissues, litter and soil organic matter.

    Science.gov (United States)

    Liu, Jun; Wu, Nana; Wang, Hui; Sun, Jianfei; Peng, Bo; Jiang, Ping; Bai, Edith

    2016-07-01

    Increasing nitrogen (N) deposition or fertilization has been found to significantly affect carbon (C) cycling. However, a comprehensive understanding of how different C chemical components of plant, litter, and soil would respond to external N addition is still lacking. We compiled data of 1,160 observations from 52 individual studies and conducted a meta-analysis of N addition effects on 18 variables related to C chemical compositions in terrestrial ecosystems. Results showed that plant lignin (+7.13%), plant protein (+25.94%), and soil lignin (+7.30%) were significantly increased by N addition, and plant hemicellulose (-4.39%) was significantly decreased, whereas plant fiber, plant cellulose, plant non-structural carbohydrate (NSC), litter lignin, and litter cellulose were not significantly changed. The effects of N addition on C chemical composition varied among different ecosystems/plant types and different forms of N addition. Increasing treatment duration did not significantly change the effects of N addition on the chemical composition of plant, litter, and soil C. With increasing N addition rate, the effect of N addition on plant lignin, plant fiber, plant cellulose, and plant protein increased, while the effect of N addition on plant hemicellulose, plant NSC, and litter cellulose became more negative. Our meta-analysis provided a systematic evaluation of the responses of different C chemical components to N addition in the plant-litter-soil continuum. Results suggest that the change of plant and soil C chemical composition under N addition may be beneficial for ecosystem C sequestration and could affect ecosystem structure and function in the future. © 2016 by the Ecological Society of America.

  19. Aquatic passive sampling of perfluorinated chemicals with polar organic chemical integrative sampler and environmental factors affecting sampling rate.

    Science.gov (United States)

    Li, Ying; Yang, Cunman; Bao, Yijun; Ma, Xueru; Lu, Guanghua; Li, Yi

    2016-08-01

    A modified polar organic chemical integrative sampler (POCIS) could provide a convenient way of monitoring perfluorinated chemicals (PFCs) in water. In the present study, the modified POCIS was calibrated to monitor PFCs. The effects of water temperature, pH, and dissolved organic matter (DOM) on the sampling rate (R s) of PFCs were evaluated with a static renewal system. During laboratory validation over a 14-day period, the uptake kinetics of PFCs was linear with the POCIS. DOM and water temperature slightly influenced POCIS uptake rates, which is in consistent with the theory for uptake into POCIS. Therefore, within a narrow span of DOM and water temperatures, it was unnecessary to adjust the R s value for POCIS. Laboratory experiments were conducted with water over pH ranges of 3, 7, and 9. The R s values declined significantly with pH increase for PFCs. Although pH affected the uptake of PFCs, the effect was less than twofold. Application of the R s value to analyze PFCs with POCIS deployed in the field provided similar concentrations obtained from grab samples.

  20. Systematic chemical variations in large 3AB iron meteorites: Clues to core crystallization

    Science.gov (United States)

    Haack, H.; Scott, E. R. D.; Rubio, G. S.; Gutierrez, D. F.; Lewis, C. F.; Wasson, J. T.; Brooks, R. R.; Guo, X.; Ryan, D. E.; Holzbecher, J.

    1993-01-01

    Analysis of numerous individual iron meteorites have shown that fractional crystallization of iron cores result in variations in chemical concentration of the solid core which span several orders of magnitude. The magnitude and direction of the resulting spatial gradients in the core can provide clues to the physical nature of the core crystallization process. We have analyzed suites of samples from three large 3AB irons (Cape York, 58t; Chupaderos, 24t; Morito, 10t) in order to estimate local chemical gradients. Initial results for the concentrations of Ge, Pd, Pt (Massey group), Ir, Au, As, Co, Os, and Rh (Dalhouse group), and P (Arizona group) show significant ranges among the Cape York and Chupaderos samples and marginally significant ranges among the Morito samples. Measurements of Au, Ir, Co, Ni, Cu, Ga, As, W, Re (from UCLA) and Ni and Co (Arizona group) are in progress. We find a spatial Ir gradient in Chupaderos with a magnitude similar to the one reported for Agpalilik (Cape York iron) by Esbensen et al.

  1. Seasonal Variation, Chemical Composition and Antioxidant Activity of Brazilian Propolis Samples

    Directory of Open Access Journals (Sweden)

    Érica Weinstein Teixeira

    2010-01-01

    Full Text Available Total phenolic contents, antioxidant activity and chemical composition of propolis samples from three localities of Minas Gerais state (southeast Brazil were determined. Total phenolic contents were determined by the Folin–Ciocalteau method, antioxidant activity was evaluated by DPPH, using BHT as reference, and chemical composition was analyzed by GC/MS. Propolis from Itapecerica and Paula Cândido municipalities were found to have high phenolic contents and pronounced antioxidant activity. From these extracts, 40 substances were identified, among them were simple phenylpropanoids, prenylated phenylpropanoids, sesqui- and diterpenoids. Quantitatively, the main constituent of both samples was allyl-3-prenylcinnamic acid. A sample from Virginópolis municipality had no detectable phenolic substances and contained mainly triterpenoids, the main constituents being α- and β-amyrins. Methanolic extracts from Itapecerica and Paula Cândido exhibited pronounced scavenging activity towards DPPH, indistinguishable from BHT activity. However, extracts from Virginópolis sample exhibited no antioxidant activity. Total phenolic substances, GC/MS analyses and antioxidant activity of samples from Itapecerica collected monthly over a period of 1 year revealed considerable variation. No correlation was observed between antioxidant activity and either total phenolic contents or contents of artepillin C and other phenolic substances, as assayed by CG/MS analysis.

  2. Does the anti-hypertensive drug clonidine affect the short-term variation in CTG recordings?

    Science.gov (United States)

    Thornton, Charlene E; Makris, Angela; Tooher, Jane M; Ogle, Robert F; Hennessy, Annemarie

    2010-10-01

    Cardiotocographic (CTG) recordings of the fetal heart remain standard obstetric practice among hypertensive women. Changes in the short-term variation (STV) in the fetal heart are often attributed to the effect of anti-hypertensive medications, regardless of the fact that this principle has never been validated. To assess the STV of CTG recordings pre- and post- the anti-hypertensive medication, clonidine. Forty hypertensive pregnant women, already receiving the anti-hypertensive clonidine, were recruited. The CTGs were conducted pre- and post-dose administration. The CTGs were assessed by the Sonicaid Team® automated CTG analysis (Oxford Instruments, UK) to avoid CTG assessor bias. Baseline fetal heart rate (FHR) (delta change from pre- and post-dose) and STV were compared using spss v.14® utilising Student t-tests. No statistical difference was found in the pre- and post-baseline FHRs (P = 0.48). The mean delta baseline heart rate before and after drug administration was -0.54 bpm. The STV of the CTGs recorded pre- and post-clonidine dose was also not affected by administration of the drug (P = 0.34). The mean delta STV before and after drug administration was 0.39 ms. Two women received betamethasone 12 mg intramuscularly within the 12-h period prior to CTG recordings to enhance fetal lung maturity. The mean STV for the fetuses of these women pre-drug was 4.8 ms and 13.2 ms post-administration. This was the largest delta seen in all STVs recorded in this dataset. The anti-hypertensive drug clonidine does not alter baseline FHRs or affect the STV of the FHR in hypertensive pregnant women. © 2010 The Authors. Australian and New Zealand Journal of Obstetrics and Gynaecology © 2010 The Royal Australian and New Zealand College of Obstetricians and Gynaecologists.

  3. How variation in head pitch could affect image matching algorithms for ant navigation.

    Science.gov (United States)

    Ardin, Paul; Mangan, Michael; Wystrach, Antoine; Webb, Barbara

    2015-06-01

    Desert ants are a model system for animal navigation, using visual memory to follow long routes across both sparse and cluttered environments. Most accounts of this behaviour assume retinotopic image matching, e.g. recovering heading direction by finding a minimum in the image difference function as the viewpoint rotates. But most models neglect the potential image distortion that could result from unstable head motion. We report that for ants running across a short section of natural substrate, the head pitch varies substantially: by over 20 degrees with no load; and 60 degrees when carrying a large food item. There is no evidence of head stabilisation. Using a realistic simulation of the ant's visual world, we demonstrate that this range of head pitch significantly degrades image matching. The effect of pitch variation can be ameliorated by a memory bank of densely sampled along a route so that an image sufficiently similar in pitch and location is available for comparison. However, with large pitch disturbance, inappropriate memories sampled at distant locations are often recalled and navigation along a route can be adversely affected. Ignoring images obtained at extreme pitches, or averaging images over several pitches, does not significantly improve performance.

  4. Neural plasticity is affected by stress and heritable variation in stress coping style.

    Science.gov (United States)

    Johansen, Ida B; Sørensen, Christina; Sandvik, Guro K; Nilsson, Göran E; Höglund, Erik; Bakken, Morten; Overli, Oyvind

    2012-06-01

    Here we use a comparative model to investigate how behavioral and physiological traits correlate with neural plasticity. Selection for divergent post-stress cortisol levels in rainbow trout (Oncorhynchus mykiss) has yielded low- (LR) and high responsive (HR) lines. Recent reports show low behavioral flexibility in LR compared to HR fish and we hypothesize that this divergence is caused by differences in neural plasticity. Genes involved in neural plasticity and neurogenesis were investigated by quantitative PCR in brains of LR and HR fish at baseline conditions and in response to two different stress paradigms: short-term confinement (STC) and long-term social (LTS) stress. Expression of proliferating cell nuclear antigen (PCNA), neurogenic differentiation factor (NeuroD) and doublecortin (DCX) was generally higher in HR compared to LR fish. STC stress led to increased expression of PCNA and brain-derived neurotrophic factor (BDNF) in both lines, whereas LTS stress generally suppressed PCNA and NeuroD expression while leaving BDNF expression unaltered. These results indicate that the transcription of neuroplasticity-related genes is associated with variation in coping style, while also being affected by STC - and LTS stress in a biphasic manner. A higher degree of neural plasticity in HR fish may provide the substrate for enhanced behavioral flexibility. Copyright © 2012 Elsevier Inc. All rights reserved.

  5. Diurnal temperature variations affect development of a herbivorous arthropod pest and its predators.

    Directory of Open Access Journals (Sweden)

    Dominiek Vangansbeke

    Full Text Available The impact of daily temperature variations on arthropod life history remains woefully understudied compared to the large body of research that has been carried out on the effects of constant temperatures. However, diurnal varying temperature regimes more commonly represent the environment in which most organisms thrive. Such varying temperature regimes have been demonstrated to substantially affect development and reproduction of ectothermic organisms, generally in accordance with Jensen's inequality. In the present study we evaluated the impact of temperature alternations at 4 amplitudes (DTR0, +5, +10 and +15°C on the developmental rate of the predatory mites Phytoseiulus persimilis Athias-Henriot and Neoseiulus californicus McGregor (Acari: Phytoseiidae and their natural prey, the two-spotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae. We have modelled their developmental rates as a function of temperature using both linear and nonlinear models. Diurnally alternating temperatures resulted in a faster development in the lower temperature range as compared to their corresponding mean constant temperatures, whereas the opposite was observed in the higher temperature range. Our results indicate that Jensen's inequality does not suffice to fully explain the differences in developmental rates at constant and alternating temperatures, suggesting additional physiological responses play a role. It is concluded that diurnal temperature range should not be ignored and should be incorporated in predictive models on the phenology of arthropod pests and their natural enemies and their performance in biological control programmes.

  6. Nanoscale Chemical Processes Affecting Storage Capacities and Seals during Geologic CO2 Sequestration.

    Science.gov (United States)

    Jun, Young-Shin; Zhang, Lijie; Min, Yujia; Li, Qingyun

    2017-07-18

    Geologic CO2 sequestration (GCS) is a promising strategy to mitigate anthropogenic CO2 emission to the atmosphere. Suitable geologic storage sites should have a porous reservoir rock zone where injected CO2 can displace brine and be stored in pores, and an impermeable zone on top of reservoir rocks to hinder upward movement of buoyant CO2. The injection wells (steel casings encased in concrete) pass through these geologic zones and lead CO2 to the desired zones. In subsurface environments, CO2 is reactive as both a supercritical (sc) phase and aqueous (aq) species. Its nanoscale chemical reactions with geomedia and wellbores are closely related to the safety and efficiency of CO2 storage. For example, the injection pressure is determined by the wettability and permeability of geomedia, which can be sensitive to nanoscale mineral-fluid interactions; the sealing safety of the injection sites is affected by the opening and closing of fractures in caprocks and the alteration of wellbore integrity caused by nanoscale chemical reactions; and the time scale for CO2 mineralization is also largely dependent on the chemical reactivities of the reservoir rocks. Therefore, nanoscale chemical processes can influence the hydrogeological and mechanical properties of geomedia, such as their wettability, permeability, mechanical strength, and fracturing. This Account reviews our group's work on nanoscale chemical reactions and their qualitative impacts on seal integrity and storage capacity at GCS sites from four points of view. First, studies on dissolution of feldspar, an important reservoir rock constituent, and subsequent secondary mineral precipitation are discussed, focusing on the effects of feldspar crystallography, cations, and sulfate anions. Second, interfacial reactions between caprock and brine are introduced using model clay minerals, with focuses on the effects of water chemistries (salinity and organic ligands) and water content on mineral dissolution and surface

  7. Variation of Hydroxyapatite Content in Soft Gelatin Affects Mesenchymal Stem Cell Differentiation

    Directory of Open Access Journals (Sweden)

    Fahsai Kantawong

    2016-01-01

    Full Text Available Gelatin is a common material used in tissue engineering and hydroxyapatite (HA has a composition and structure similar to natural bone mineral. HA is also used to increase the adhesion ability of scaffolds. The physical and mechanical properties of gelatin, together with the chemical properties of HA, can affect cell differentiation. The main purpose of this study is to investigate the gene expression of human mesenchymal stem cells (HMSCs upon culturing on gelatin composite with HA. Low amounts of HA were introduced into the gelatin in order to modulate properties of gelatin. Three types of hydrogel were fabricated by glutaraldehyde crosslinking before lyophilization to produce the porous 3D structure: (1 pure gelatin, (2 0.5 mg/ml HA in gelatin, and (3 1 mg/ml HA in gelatin. The fabricated hydrogels were used as scaffolds to cultivate HMSCs for two periods - 24 hours and 3 weeks. The results showed that all types of fabricated hydrogels could be used to cultivate HMSCs. Changes of gene expressions indicated that the HMSCs cultured on the 1 mg/ml HA in gelatin showed neuronal lineage-specific differentiation.

  8. Factors affecting chemical variability of essential oils: a review of recent developments.

    Science.gov (United States)

    Barra, Andrea

    2009-08-01

    This review, covering mainly papers of the last decade, focuses on recent findings on the different factors affecting the chemical composition of essential oils, such as exogenous and endogenous factors. The endogenous factors are related to anatomical and physiological characteristics of the plants and to the biosynthetic pathways of the volatiles, which might change in either the different tissues of the plants or in different seasons, but also could be influenced by DNA adaptation. The exogenous factors, over a long period, might affect some of the genes responsible for volatiles formation. Those factors lead to ecotypes or chemotypes in the same plant species. In the last few years chemotaxonomy has been widely used to classify plants with essential oils characterized by intra-specific chemical polymorphism. It could be evidenced that chemotypes are frequently genotypes and recently the application of the Random Amplified Polymorphic DNA (RAPD) markers, coupled with powerful statistical methods, appeared to be useful in discriminating the different genotypes. The data presented led to the suggestion that further chemotaxonomic studies should be the result of the analysis of morphological traits combined both with chemical and molecular markers.

  9. Possible environmental chemical cues affecting behaviour of the mangrove gastropod Cerithidea decollata

    Science.gov (United States)

    Lazzeri, Anna Marta

    2017-03-01

    The Indo-West Pacific mangrove gastropod Cerithidea decollata feeds on the ground at low tide and climbs the trees (Avicennia marina) two hours before the arrival of water, settling well above the level that the incoming tide will reach at high tide (from 0 to 80 cm, depending on the tidal phase). In addition, it has been shown that these snails climb twice as high when translocated to lower shore sites (dominated by Rhizophora mucronata), where C. decollata is missing and the high water can reach 1.6 m instead of about 80 cm as within the snail home environment. The study assesses the possible role of chemical cues in the afore-mentioned behaviours. The hypothesis that snails may foresee the periodical tide level variation thanks to airborne chemical cues, possibly released by trees or sediments, has been rejected. On the other hand, airborne chemical cues released by R. mucronata may play a role in inducing snails translocated to low shore sites to climb much higher than control, allowing them to avoid submersion.

  10. Chemical change of leaves during breakdown affects associated invertebrates in a subtropical stream

    Directory of Open Access Journals (Sweden)

    Alan Mosele Tonin

    2014-09-01

    Full Text Available AIMS: Our objective was assess the effects of leaf chemical change during breakdown on the associated invertebrates. METHODS: We evaluate the chemical composition of leaves (of two tree species; Sebastiania brasiliensis and Campomanesia xanthocarpa and the density of invertebrates during leaf breakdown (on four incubation times; 3, 7, 14 and 22 days in a subtropical stream. Linear multiple regression analysis were performed to evaluate the relationship between invertebrate density and changes in leaf chemical during breakdown. RESULTS: Density of invertebrates was related to the chemical composition of leaves. There was a positive correlation of K (β = 3.48 and a negative of C:N (β = -0.34, polyphenols (β = -0.16, Ca (β = -2.98 and Mg (β = -2.58 with the total density of invertebrates. Density of invertebrates on leaves reached 38 ± 9 and 192 ± 31 individuals g-1 leaf DM during the first 3 and 7 days of incubation, had decreased by the 14th day (117 ± 18 and then increased after 22 days (270 ± 41. CONCLUSIONS: We conclude that changes in the chemistry of decomposing leaves affect invertebrate colonization process. This conclusion reinforce the importance of understand the dynamic of energy and nutrients and its association with the biological communities of tropical riparian ecosystems.

  11. Variation in chemical composition and physical characteristics of cereal grains from different genotypes.

    Science.gov (United States)

    Rodehutscord, Markus; Rückert, Christine; Maurer, Hans Peter; Schenkel, Hans; Schipprack, Wolfgang; Bach Knudsen, Knud Erik; Schollenberger, Margit; Laux, Meike; Eklund, Meike; Siegert, Wolfgang; Mosenthin, Rainer

    2016-01-01

    Genotypes of cereal grains, including winter barley (n = 21), maize (n = 27), oats (n = 14), winter rye (n = 22), winter triticale (n = 21) and winter wheat (n = 29), were assayed for their chemical composition and physical characteristics as part of the collaborative research project referred to as GrainUp. Genotypes of one grain species were grown on the same site, except maize. In general, concentrations of proximate nutrients were not largely different from feed tables. The coefficient of variation (CV) for the ether extract concentration of maize was high because the data pool comprised speciality maize bred for its high oil content. A subset of 8 barley, 20 rye, 20 triticale and 20 wheat samples was analysed to differ significantly in several carbohydrate fractions. Gross energy concentration of cereal grains could be predicted from proximate nutrient concentration with good accuracy. The mean lysine concentration of protein was the highest in oats (4.2 g/16 g N) and the lowest in wheat (2.7 g/16 g N). Significant differences were also detected in the concentrations of macro elements as well as iron, manganese, zinc and copper. Concentrations of arsenic, cadmium and lead were below the limit of detection. The concentration of lower inositol phosphates was low, but some inositol pentaphosphates were detected in all grains. In barley, relatively high inositol tetraphosphate concentration also was found. Intrinsic phytase activity was the highest in rye, followed by triticale, wheat, barley and maize, and it was not detectable in oats. Substantial differences were seen in the thousand seed weight, test weight, falling number and extract viscoelasticity characteristics. The study is a comprehensive overview of the composition of different cereal grain genotypes when grown on the same location. The relevance of the variation in composition for digestibility in different animal species will be subject of other communications.

  12. Modelling and optimization of film thickness variation for plasma enhanced chemical vapour deposition processes

    Science.gov (United States)

    Waddell, Ewan; Gibson, Des; Lin, Li; Fu, Xiuhua

    2011-09-01

    This paper describes a method for modelling film thickness variation across the deposition area within plasma enhanced chemical vapour deposition (PECVD) processes. The model enables identification and optimization of film thickness uniformity sensitivities to electrode configuration, temperature, deposition system design and gas flow distribution. PECVD deposition utilizes a co-planar 300mm diameter electrodes with separate RF power matching to each electrode. The system has capability to adjust electrode separation and electrode temperature as parameters to optimize uniformity. Vacuum is achieved using dry pumping with real time control of butterfly valve position for active pressure control. Comparison between theory and experiment is provided for PECVD of diamond-like-carbon (DLC) deposition onto flat and curved substrate geometries. The process utilizes butane reactive feedstock with an argon carrier gas. Radiofrequency plasma is used. Deposited film thickness sensitivities to electrode geometry, plasma power density, pressure and gas flow distribution are demonstrated. Use of modelling to optimise film thickness uniformity is demonstrated. Results show DLC uniformity of 0.30% over a 200 mm flat zone diameter within overall electrode diameter of 300mm. Thickness uniformity of 0.75% is demonstrated over a 200mm diameter for a non-conformal substrate geometry. Use of the modelling method for PECVD using metal-organic chemical vapour deposition (MOCVD) feedstock is demonstrated, specifically for deposition of silica films using metal-organic tetraethoxy-silane. Excellent agreement between experimental and theory is demonstrated for conformal and non-conformal geometries. The model is used to explore scalability of PECVD processes and trade-off against film thickness uniformity. Application to MEMS, optical coatings and thin film photovoltaics is discussed.

  13. Social context-induced song variation affects female behavior and gene expression.

    Directory of Open Access Journals (Sweden)

    Sarah C Woolley

    2008-03-01

    Full Text Available Social cues modulate the performance of communicative behaviors in a range of species, including humans, and such changes can make the communication signal more salient. In songbirds, males use song to attract females, and song organization can differ depending on the audience to which a male sings. For example, male zebra finches (Taeniopygia guttata change their songs in subtle ways when singing to a female (directed song compared with when they sing in isolation (undirected song, and some of these changes depend on altered neural activity from a specialized forebrain-basal ganglia circuit, the anterior forebrain pathway (AFP. In particular, variable activity in the AFP during undirected song is thought to actively enable syllable variability, whereas the lower and less-variable AFP firing during directed singing is associated with more stereotyped song. Consequently, directed song has been suggested to reflect a "performance" state, and undirected song a form of vocal motor "exploration." However, this hypothesis predicts that directed-undirected song differences, despite their subtlety, should matter to female zebra finches, which is a question that has not been investigated. We tested female preferences for this natural variation in song in a behavioral approach assay, and we found that both mated and socially naive females could discriminate between directed and undirected song-and strongly preferred directed song. These preferences, which appeared to reflect attention especially to aspects of song variability controlled by the AFP, were enhanced by experience, as they were strongest for mated females responding to their mate's directed songs. We then measured neural activity using expression of the immediate early gene product ZENK, and found that social context and song familiarity differentially modulated the number of ZENK-expressing cells in telencephalic auditory areas. Specifically, the number of ZENK-expressing cells in the

  14. Variation in barometric pressure in Melbourne does not significantly affect the BTPS correction factor.

    Science.gov (United States)

    Johns, David P; Hartley, M Faizel; Burns, Graham; Thompson, Bruce R

    2004-08-01

    The conventional BTPS (body temperature and pressure, saturated with water vapour) correction factor varies with ambient barometric pressure (P(B)) and many lung function laboratories measure P(B) daily. The aim was to investigate whether a fixed value for P(B) could replace daily measurements. P(B) was measured daily over a 12-month period. The highest and lowest values in Melbourne in the last century were also recorded from data published by the Bureau of Meteorology. Using these P(B) values, the BTPS factor was determined for a range of spirometer temperatures and compared to the BTPS factors obtained using a fixed ambient pressure of 101.3 kPa. The mean (SD) P(B) measured over the 12-month period was 102.2 kPa (0.64) with a range of 99.9-103.6 kPa. The level of disagreement between the BTPS factor calculated using a P(B) of 101.3 kPa instead of the measured value was greater at lower temperatures. Over the extremes of P(B) during the last century (98.0-104.3 kPa) the use of a standard pressure (101.3 kPa) produced an error in the BTPS factor of variations in P(B) do not significantly affect the magnitude of the conventional BTPS correction factor and a fixed value, such as 101.3 kPa at sea level, can be used with little error.

  15. Phylogenetic estimates of diversification rate are affected by molecular rate variation.

    Science.gov (United States)

    Duchêne, D A; Hua, X; Bromham, L

    2017-10-01

    Molecular phylogenies are increasingly being used to investigate the patterns and mechanisms of macroevolution. In particular, node heights in a phylogeny can be used to detect changes in rates of diversification over time. Such analyses rest on the assumption that node heights in a phylogeny represent the timing of diversification events, which in turn rests on the assumption that evolutionary time can be accurately predicted from DNA sequence divergence. But there are many influences on the rate of molecular evolution, which might also influence node heights in molecular phylogenies, and thus affect estimates of diversification rate. In particular, a growing number of studies have revealed an association between the net diversification rate estimated from phylogenies and the rate of molecular evolution. Such an association might, by influencing the relative position of node heights, systematically bias estimates of diversification time. We simulated the evolution of DNA sequences under several scenarios where rates of diversification and molecular evolution vary through time, including models where diversification and molecular evolutionary rates are linked. We show that commonly used methods, including metric-based, likelihood and Bayesian approaches, can have a low power to identify changes in diversification rate when molecular substitution rates vary. Furthermore, the association between the rates of speciation and molecular evolution rate can cause the signature of a slowdown or speedup in speciation rates to be lost or misidentified. These results suggest that the multiple sources of variation in molecular evolutionary rates need to be considered when inferring macroevolutionary processes from phylogenies. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

  16. Spatial Variation and Resuscitation Process Affecting Survival after Out-of-Hospital Cardiac Arrests (OHCA.

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    Chien-Chou Chen

    Full Text Available Ambulance response times and resuscitation efforts are critical predictors of the survival rate after out-of-hospital cardiac arrests (OHCA. On the other hand, rural-urban differences in the OHCA survival rates are an important public health issue.We retrospectively reviewed the January 2011-December 2013 OHCA registry data of Kaohsiung City, Taiwan. With particular focus on geospatial variables, we aimed to unveil risk factors predicting the overall OHCA survival until hospital admission. Spatial analysis, network analysis, and the Kriging method by using geographic information systems were applied to analyze spatial variations and calculate the transport distance. Logistic regression was used to identify the risk factors for OHCA survival.Among the 4,957 patients, the overall OHCA survival to hospital admission was 16.5%. In the multivariate analysis, female sex (adjusted odds ratio:, AOR, 1.24 [1.06-1.45], events in public areas (AOR: 1.30 [1.05-1.61], exposure to automated external defibrillator (AED shock (AOR: 1.70 [1.30-2.23], use of laryngeal mask airway (LMA (AOR: 1.35 [1.16-1.58], non-trauma patients (AOR: 1.41 [1.04-1.90], ambulance bypassed the closest hospital (AOR: 1.28 [1.07-1.53], and OHCA within the high population density areas (AOR: 1.89 [1.55-2.32] were positively associated with improved OHCA survival. By contrast, a prolonged total emergency medical services (EMS time interval was negatively associated with OHCA survival (AOR: 0.98 [0.96-0.99].Resuscitative efforts, such as AED or LMA use, and a short total EMS time interval improved OHCA outcomes in emergency departments. The spatial heterogeneity of emergency medical resources between rural and urban areas might affect survival rate.

  17. Study on effect of the surface variation of colloidal silica abrasive during chemical mechanical polishing of sapphire

    Science.gov (United States)

    Bun-Athuek, Natthaphon; Yoshimoto, Yutaka; Sakai, Koya; Khajornrungruang, Panart; Suzuki, Keisuke

    2017-07-01

    The surface and diameter size variations of colloidal silica particles during the chemical mechanical polishing (CMP) of sapphire substrates were investigated using different particle diameters of 20 and 55 nm. Dynamic light scattering (DLS) results show that the silica particles became larger after CMP under both conditions. The increase in particle size in the slurry was proportional to the material removal amount (MRA) as a function of the removed volume of sapphire substrates by CMP and affected the material removal rate (MRR). Transmission electron microscopy (TEM) images revealed an increase in the size of the fine particles and a change in their surface shape in the slurry. The colloidal silica was coated with the material removed from the substrate during CMP. In this case, the increase in the size of 55 nm diameter particles is larger than that of 20 nm diameter particles. X-ray fluorescence spectrometry (XRF) results indicate that the aluminum element from polished sapphire substrates adhered to the surfaces of silica particles. Therefore, MRR decreases with increasing of polishing time owing to the degradation of particles in the slurry.

  18. Phenotypic Variations in the Foliar Chemical Profile of Persea americana Mill. cv. Hass.

    Science.gov (United States)

    García-Rodríguez, Yolanda Magdalena; Torres-Gurrola, Guadalupe; Meléndez-González, Claudio; Espinosa-García, Francisco J

    2016-12-01

    The Hass avocado tree Persea americana cv. Hass was derived from a single hybrid tree of P. americana var. drymifolia and P. americana var. guatemalensis, and it is propagated clonally by grafting. This cultivar is the most widely planted in the world but its profile of secondary metabolites has been studied rarely despite of its importance in plant protection. We illustrate the variability of the volatilome of mature leaves by describing the average chemical composition and the phenotypic variability found in 70 trees. Contrary to the uniformity expected in the Hass cultivar, high variability coefficients were found for most of the 36 detected foliar volatile compounds; furthermore we found six chemotypes grouping the foliar phenotypes of the sampled trees using hierarchical cluster analysis. About 48% of trees were grouped in one chemotype; five chemotypes grouped the remaining trees. The compounds that determined these chemotypes were: estragole, α-farnesene, β-caryophyllene, germacrene D, α-cubebene and eugenol. This striking variation in a cultivar propagated clonally is discussed in terms of somatic mutation. © 2016 Wiley-VHCA AG, Zurich, Switzerland.

  19. Habitat Fragmentation Differentially Affects Genetic Variation, Phenotypic Plasticity and Survival in Populations of a Gypsum Endemic.

    Science.gov (United States)

    Matesanz, Silvia; Rubio Teso, María Luisa; García-Fernández, Alfredo; Escudero, Adrián

    2017-01-01

    Habitat fragmentation, i.e., fragment size and isolation, can differentially alter patterns of neutral and quantitative genetic variation, fitness and phenotypic plasticity of plant populations, but their effects have rarely been tested simultaneously. We assessed the combined effects of size and connectivity on these aspects of genetic and phenotypic variation in populations of Centaurea hyssopifolia , a narrow endemic gypsophile that previously showed performance differences associated with fragmentation. We grew 111 maternal families sampled from 10 populations that differed in their fragment size and connectivity in a common garden, and characterized quantitative genetic variation, phenotypic plasticity to drought for key functional traits, and plant survival, as a measure of population fitness. We also assessed neutral genetic variation within and among populations using eight microsatellite markers. Although C. hyssopifolia is a narrow endemic gypsophile, we found substantial neutral genetic variation and quantitative variation for key functional traits. The partition of genetic variance indicated that a higher proportion of variation was found within populations, which is also consistent with low population differentiation in molecular markers, functional traits and their plasticity. This, combined with the generally small effect of habitat fragmentation suggests that gene flow among populations is not restricted, despite large differences in fragment size and isolation. Importantly, population's similarities in genetic variation and plasticity did not reflect the lower survival observed in isolated populations. Overall, our results indicate that, although the species consists of genetically variable populations able to express functional plasticity, such aspects of adaptive potential may not always reflect populations' survival. Given the differential effects of habitat connectivity on functional traits, genetic variation and fitness, our study highlights

  20. Habitat Fragmentation Differentially Affects Genetic Variation, Phenotypic Plasticity and Survival in Populations of a Gypsum Endemic

    Directory of Open Access Journals (Sweden)

    Silvia Matesanz

    2017-05-01

    Full Text Available Habitat fragmentation, i.e., fragment size and isolation, can differentially alter patterns of neutral and quantitative genetic variation, fitness and phenotypic plasticity of plant populations, but their effects have rarely been tested simultaneously. We assessed the combined effects of size and connectivity on these aspects of genetic and phenotypic variation in populations of Centaurea hyssopifolia, a narrow endemic gypsophile that previously showed performance differences associated with fragmentation. We grew 111 maternal families sampled from 10 populations that differed in their fragment size and connectivity in a common garden, and characterized quantitative genetic variation, phenotypic plasticity to drought for key functional traits, and plant survival, as a measure of population fitness. We also assessed neutral genetic variation within and among populations using eight microsatellite markers. Although C. hyssopifolia is a narrow endemic gypsophile, we found substantial neutral genetic variation and quantitative variation for key functional traits. The partition of genetic variance indicated that a higher proportion of variation was found within populations, which is also consistent with low population differentiation in molecular markers, functional traits and their plasticity. This, combined with the generally small effect of habitat fragmentation suggests that gene flow among populations is not restricted, despite large differences in fragment size and isolation. Importantly, population’s similarities in genetic variation and plasticity did not reflect the lower survival observed in isolated populations. Overall, our results indicate that, although the species consists of genetically variable populations able to express functional plasticity, such aspects of adaptive potential may not always reflect populations’ survival. Given the differential effects of habitat connectivity on functional traits, genetic variation and fitness

  1. Accessible protocol for practice classroom about physical and chemical factors that affect the biomembranes integrity

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    Thiago Barros Galvão

    2012-12-01

    Full Text Available The aim of the current work is to review a protocol used in practical classes to demonstrate some factors that affect biomembrane integrity. Sugar-beet fragments were utilized as the experimental model as membrane damage could be visualized by leakage of betacyanins, hydrophilic pigments accumulated in the cell vacuoles. The tests were carried out as discrete experiments utilizing physical agents and chemical products present in the student daily routine. To test the effect of temperature, sugar-beet fragments were submitted to heat, cold or both at different times of exposition. When chemical products were tested, sugar-beet fragments were exposed to organic solvents (common alcohol and acetone or polar and amphipathic substances (disinfectant, detergent, hydrogen peroxide, and sodium hypochlorite. The obtained results were discussed in terms of the capacity of the physical and chemical factors to cause membrane damage. The review of this protocol using reagents that are present in the student daily routine were able to demonstrate clearly the effect of the different tested factors, allowing the utilization of this practical class under limited conditions.

  2. Variation in Chemical Defense Among Natural Populations of Common Toad, Bufo bufo, Tadpoles: the Role of Environmental Factors.

    Science.gov (United States)

    Bókony, Veronika; Móricz, Ágnes M; Tóth, Zsófia; Gál, Zoltán; Kurali, Anikó; Mikó, Zsanett; Pásztor, Katalin; Szederkényi, Márk; Tóth, Zoltán; Ujszegi, János; Üveges, Bálint; Krüzselyi, Dániel; Capon, Robert J; Hoi, Herbert; Hettyey, Attila

    2016-04-01

    Defensive toxins are widespread in nature, yet we know little about how various environmental factors shape the evolution of chemical defense, especially in vertebrates. In this study we investigated the natural variation in the amount and composition of bufadienolide toxins, and the relative importance of ecological factors in predicting that variation, in larvae of the common toad, Bufo bufo, an amphibian that produces toxins de novo. We found that tadpoles' toxin content varied markedly among populations, and the number of compounds per tadpole also differed between two geographical regions. The most consistent predictor of toxicity was the strength of competition, indicating that tadpoles produced more compounds and larger amounts of toxins when coexisting with more competitors. Additionally, tadpoles tended to contain larger concentrations of bufadienolides in ponds that were less prone to desiccation, suggesting that the costs of toxin production can only be afforded by tadpoles that do not need to drastically speed up their development. Interestingly, this trade-off was not alleviated by higher food abundance, as periphyton biomass had negligible effect on chemical defense. Even more surprisingly, we found no evidence that higher predation risk enhances chemical defenses, suggesting that low predictability of predation risk and high mortality cost of low toxicity might select for constitutive expression of chemical defense irrespective of the actual level of predation risk. Our findings highlight that the variation in chemical defense may be influenced by environmental heterogeneity in both the need for, and constraints on, toxicity as predicted by optimal defense theory.

  3. Variation in Biofilm Stability with Decreasing pH Affects Porous Medium Hydraulic Properties

    Science.gov (United States)

    Kirk, M. F.; Santillan, E. F.; McGrath, L. K.; Altman, S. J.

    2010-12-01

    Changes to microbial communities caused by subsurface CO2 injection may have many consequences, including possible impacts to CO2 transport. We used column experiments to examine how decreasing pH, a geochemical change associated with CO2 injection, will affect biofilm stability and ultimately the hydraulic properties of porous media. Columns consisted of 1 mm2 square capillary tubes filled with 105-150 µm diameter glass beads. Artificial groundwater medium containing 1 mM glucose was pumped through the columns at a rate of 0.01 mL/min (q = 14.4 m/day; Re = 0.03). Columns were inoculated with 3 × 10^8 CFU (avg.) of Pseudomonas fluorescens, a model biofilm former, transformed with a green fluorescent protein. Biomass distribution and transport was examined using scanning laser confocal microscopy and effluent plating. Variation in the bulk hydraulic properties of the columns was measured using manometers. In an initial experiment, biofilm growth was allowed to occur for seven days in medium with pH 7.3. Within this period, cells uniformly coated bead surfaces, effluent cell numbers stabilized at 1 × 10^9 CFU/mL, and hydraulic conductivity (K) decreased 77%. Next, medium with pH 4 was introduced. As a result, biomass within the reactor redistributed from bead surfaces to pores, effluent cell numbers decreased to 3 × 10^5 CFU/mL, and K decreased even further (>94% reduction). This decreased K was maintained until the experiment was terminated, seven days after introducing low pH medium. These results suggest that changes in biomass distribution as a result of decreased pH may initially limit transport of solubility-trapped CO2 following CO2 injection. Experiments in progress and planned will test this result in more detail and over longer periods of time. This material is based upon work supported as part of the Center for Frontiers of Subsurface Energy Security, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office

  4. Variation in global chemical composition of PM2.5: emerging results from SPARTAN

    Science.gov (United States)

    Snider, Graydon; Weagle, Crystal L.; Murdymootoo, Kalaivani K.; Ring, Amanda; Ritchie, Yvonne; Stone, Emily; Walsh, Ainsley; Akoshile, Clement; Anh, Nguyen Xuan; Balasubramanian, Rajasekhar; Brook, Jeff; Qonitan, Fatimah D.; Dong, Jinlu; Griffith, Derek; He, Kebin; Holben, Brent N.; Kahn, Ralph; Lagrosas, Nofel; Lestari, Puji; Ma, Zongwei; Misra, Amit; Norford, Leslie K.; Quel, Eduardo J.; Salam, Abdus; Schichtel, Bret; Segev, Lior; Tripathi, Sachchida; Wang, Chien; Yu, Chao; Zhang, Qiang; Zhang, Yuxuan; Brauer, Michael; Cohen, Aaron; Gibson, Mark D.; Liu, Yang; Vanderlei Martins, J.; Rudich, Yinon; Martin, Randall V.

    2016-08-01

    , India). Comparison of SPARTAN vs. coincident measurements from the Interagency Monitoring of Protected Visual Environments (IMPROVE) network at Mammoth Cave yielded a high degree of consistency for daily PM2.5 (r2 = 0.76, slope = 1.12), daily sulfate (r2 = 0.86, slope = 1.03), and mean fractions of all major PM2.5 components (within 6 %). Major ions generally agree well with previous studies at the same urban locations (e.g. sulfate fractions agree within 4 % for 8 out of 11 collocation comparisons). Enhanced anthropogenic dust fractions in large urban areas (e.g. Singapore, Kanpur, Hanoi, and Dhaka) are apparent from high Zn : Al ratios.The expected water contribution to aerosols is calculated via the hygroscopicity parameter κv for each filter. Mean aggregate values ranged from 0.15 (Ilorin) to 0.28 (Rehovot). The all-site parameter mean is 0.20 ± 0.04. Chemical composition and water retention in each filter measurement allows inference of hourly PM2.5 at 35 % relative humidity by merging with nephelometer measurements. These hourly PM2.5 estimates compare favourably with a beta attenuation monitor (MetOne) at the nearby US embassy in Beijing, with a coefficient of variation r2 = 0.67 (n = 3167), compared to r2 = 0.62 when κv was not considered. SPARTAN continues to provide an open-access database of PM2.5 compositional filter information and hourly mass collected from a global federation of instruments.

  5. A functional genetic variation of the 5-HT2a receptor affects human memory.

    Science.gov (United States)

    de Quervain, Dominique J-F; Henke, Katharina; Aerni, Amanda; Coluccia, Daniel; Wollmer, M Axel; Hock, Christoph; Nitsch, Roger M; Papassotiropoulos, Andreas

    2003-11-01

    Human memory capacity is highly variable across individuals and is influenced by both genetic and environmental factors. A roughly 50% heritability estimate indicates that naturally occurring genetic variations have an important impact on this cognitive ability. Therefore, we investigated a functional variation of a memory-related serotonin receptor in 349 healthy young volunteers, and found 21% poorer memory performance in subjects with the rare variant.

  6. Type of frame dependence: variation in media frames affecting attitudes via audience frames

    NARCIS (Netherlands)

    van Drunen, A.S.; Boomgaarden, H.G.; Vliegenthart, R.

    2012-01-01

    In this paper two suggested processes of framing theory (Scheufele, 1999) are tested: frame setting (media affecting audience frames) and the individual effects process (audience frames affecting attitudes or behavior). Media frames may affect opinions and behavior, however these effects are not

  7. Does litter size variation affect models of terrestrial carnivore extinction risk and management?

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    Eleanor S Devenish-Nelson

    Full Text Available BACKGROUND: Individual variation in both survival and reproduction has the potential to influence extinction risk. Especially for rare or threatened species, reliable population models should adequately incorporate demographic uncertainty. Here, we focus on an important form of demographic stochasticity: variation in litter sizes. We use terrestrial carnivores as an example taxon, as they are frequently threatened or of economic importance. Since data on intraspecific litter size variation are often sparse, it is unclear what probability distribution should be used to describe the pattern of litter size variation for multiparous carnivores. METHODOLOGY/PRINCIPAL FINDINGS: We used litter size data on 32 terrestrial carnivore species to test the fit of 12 probability distributions. The influence of these distributions on quasi-extinction probabilities and the probability of successful disease control was then examined for three canid species - the island fox Urocyon littoralis, the red fox Vulpes vulpes, and the African wild dog Lycaon pictus. Best fitting probability distributions differed among the carnivores examined. However, the discretised normal distribution provided the best fit for the majority of species, because variation among litter-sizes was often small. Importantly, however, the outcomes of demographic models were generally robust to the distribution used. CONCLUSION/SIGNIFICANCE: These results provide reassurance for those using demographic modelling for the management of less studied carnivores in which litter size variation is estimated using data from species with similar reproductive attributes.

  8. Variation in chemical components and biological activity of Pterocarya fraxinifolia Lam. stems at different developmental stages

    Directory of Open Access Journals (Sweden)

    M. Akhbari

    2017-07-01

    Full Text Available Background and objectives: Pterocarya fraxinifolia Lam. is a deciduous, fast-growing tree from walnut family. The stem barks and fruits of the plant have been used as diaphoretic in traditional medicine. Variation in the quantity and quality of the essential oil and extract of stems of the plant at different developmental stages was evaluated in addition to assessing the antimicrobial, cytotoxic and radical scavenging activities in the present study. Methods: Different developmental stages of the plant’s stem (i.e. vegetative, flowering, immature fruit and mature fruit were subjected to hydro-distillation for obtaining the essential oil. The methanol extract of the samples was obtained by Soxhlet apparatus. Chemical composition of the oils was analyzed by gas chromatography/mass spectroscopy (GC/MS. Antimicrobial activity of the oils and extracts were determined against three Gram-positive and five Gram-negative bacteria and two fungi by disc diffusion method. Antioxidant activity of the samples was evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH and β-carotene assays. Total phenolics content of extracts was determined using Folin-Ciocalteau reagent and cytotoxic effect was determined by brine shrimp lethality bioassay. Results: Hexadecanoic acid was one of the major components in all essential oil samples. All samples showed good antimicrobial activity against tested strains. Antioxidant activity of the extracts was comparable to the synthetic standard (butylated hydroxytoluene. The highest total phenolic content and cytotoxic effect were detected for the mature fruit stage of the plant extract and essential oil, respectively. Conclusion: Showing considerable antioxidant and cytotoxic effects, suggested the plant as a good candidate for further investigations.

  9. Temporal and Spatial Variation of Chemical Water Quality in a Contour Canal.

    Science.gov (United States)

    Swanson, L. A.; Lunn, R. J.

    2004-12-01

    Chemical water quality is a highly variable aspect of any water body. Historically numerous researchers have investigated the chemical variability of rivers, streams and wetlands, artificial water bodies such as canals have been largely neglected. Canals are typically hydraulically characterised by low flows and a lack of mixing processes. This can potentially lead to significant spatial variability in water chemistry, and as a result many canals in the UK regularly fail water quality targets at specific locations. Recent changes to UK legislation, following the European Water Framework Directive (2000/60/EC), have resulted in canals being subject to achieving `good ecological status'. In the case of canals, what constitutes `good ecological status' is largely unknown and little expertise is available since historically canal management has not been driven by chemical and ecological quality targets. Consequently, there is an urgent need for new research to determine the main factors influencing canal water quality and their ecological status. This research presents results from a study based on a UK contour canal, the Union Canal in central Scotland. The Union Canal typically demonstrates spatially and temporally variable levels of dissolved oxygen (DO) and orthophosphate (PO4-P): simultaneously, seasonal and diel fluctuations of DO and PO4-P are pronounced at a small number of locations. During 1995, minimum levels of DO along the canal length ranged from 9mgl-1 in Edinburgh to as low as 2mgl-1 approximately 20kms away, this then rose again to 8mgl-1 after a further distance of 2km. These acutely low levels of DO are coupled with events of excessive PO4-P up to 0.235mgl-1:10 times greater than those normally found in rivers, causing localised eutrophication and extensive fish kills. To determine the cause of the `hot spots' of poor water quality found on the Union Canal, simultaneous investigations of the hydraulic regime, spatial and temporal water quality

  10. Ocean acidification affects marine chemical communication by changing structure and function of peptide signalling molecules.

    Science.gov (United States)

    Roggatz, Christina C; Lorch, Mark; Hardege, Jörg D; Benoit, David M

    2016-12-01

    Ocean acidification is a global challenge that faces marine organisms in the near future with a predicted rapid drop in pH of up to 0.4 units by the end of this century. Effects of the change in ocean carbon chemistry and pH on the development, growth and fitness of marine animals are well documented. Recent evidence also suggests that a range of chemically mediated behaviours and interactions in marine fish and invertebrates will be affected. Marine animals use chemical cues, for example, to detect predators, for settlement, homing and reproduction. But, while effects of high CO2 conditions on these behaviours are described across many species, little is known about the underlying mechanisms, particularly in invertebrates. Here, we investigate the direct influence of future oceanic pH conditions on the structure and function of three peptide signalling molecules with an interdisciplinary combination of methods. NMR spectroscopy and quantum chemical calculations were used to assess the direct molecular influence of pH on the peptide cues, and we tested the functionality of the cues in different pH conditions using behavioural bioassays with shore crabs (Carcinus maenas) as a model system. We found that peptide signalling cues are susceptible to protonation in future pH conditions, which will alter their overall charge. We also show that structure and electrostatic properties important for receptor binding differ significantly between the peptide forms present today and the protonated signalling peptides likely to be dominating in future oceans. The bioassays suggest an impaired functionality of the signalling peptides at low pH. Physiological changes due to high CO2 conditions were found to play a less significant role in influencing the investigated behaviour. From our results, we conclude that the change of charge, structure and consequently function of signalling molecules presents one possible mechanism to explain altered behaviour under future oceanic p

  11. Elevated CO2 affects plant responses to variation in boron availability

    Science.gov (United States)

    Effects of elevated CO2 on N relations are well studied, but effects on other nutrients, especially micronutrients, are not. We investigated effects of elevated CO2 on response to variation in boron (B) availability in three unrelated species: geranium (Pelargonium x hortorum), barley (Hordeum vulga...

  12. Variation at the serotonin transporter gene influences susceptibility to bipolar affective puerperal psychosis.

    Science.gov (United States)

    Coyle, N; Jones, I; Robertson, E; Lendon, C; Craddock, N

    2000-10-28

    Up to half of parous females with bipolar disorder (manic depression) develop an episode of severe psychiatric disturbance, usually called puerperal psychosis, within a few days of giving birth. We report significant evidence (p<0.003) that variation at the serotonin transporter gene exerts a substantial (odds ratio=4) and important (population attributable fraction=69%) influence on susceptibility to such episodes.

  13. Intraspecific variation in a predator affects community structure and cascading trophic interactions.

    Science.gov (United States)

    Post, David M; Palkovacs, Eric P; Schielke, Erika G; Dodson, Stanley I

    2008-07-01

    Intraspecific phenotypic variation in ecologically important traits is widespread and important for evolutionary processes, but its effects on community and ecosystem processes are poorly understood. We use life history differences among populations of alewives, Alosa pseudoharengus, to test the effects of intraspecific phenotypic variation in a predator on pelagic zooplankton community structure and the strength of cascading trophic interactions. We focus on the effects of differences in (1) the duration of residence in fresh water (either seasonal or year-round) and (2) differences in foraging morphology, both of which may strongly influence interactions between alewives and their prey. We measured zooplankton community structure, algal biomass, and spring total phosphorus in lakes that contained landlocked, anadromous, or no alewives. Both the duration of residence and the intraspecific variation in foraging morphology strongly influenced zooplankton community structure. Lakes with landlocked alewives had small-bodied zooplankton year-round, and lakes with no alewives had large-bodied zooplankton year-round. In contrast, zooplankton communities in lakes with anadromous alewives cycled between large-bodied zooplankton in the winter and spring and small-bodied zooplankton in the summer. In summer, differences in feeding morphology of alewives caused zooplankton biomass to be lower and body size to be smaller in lakes with anadromous alewives than in lakes with landlocked alewives. Furthermore, intraspecific variation altered the strength of the trophic cascade caused by alewives. Our results demonstrate that intraspecific phenotypic variation of predators can regulate community structure and ecosystem processes by modifying the form and strength of complex trophic interactions.

  14. The Southeastern Aerosol Research and Characterization (SEARCH) study: spatial variations and chemical climatology, 1999-2010.

    Science.gov (United States)

    Blanchard, C L; Hidy, G M; Tanenbaum, S; Edgerton, E S; Hartsell, B E

    2013-03-01

    The Southeastern Aerosol Research and Characterization (SEARCH) study, which has been in continuous operation from 1999 to 2012, was implemented to investigate regional and urban air pollution in the southeastern United States. With complementary data from other networks, the SEARCH measurements provide key knowledge about long-term urban/nonurban pollution contrasts and regional climatology affecting inland locations and sites along the Gulf of Mexico coastline. Analytical approaches ranging from comparisons of mean concentrations to the application of air mass trajectories and principal component analysis provide insight into local and area-wide pollution. Gases (carbon monoxide, sulfur dioxide, nitrogen oxides, ozone, and ammonia), fine particle mass concentration, and fine particle species concentrations (including sulfate, elementary carbon, and organic carbon) are affected by a combination of regional conditions and local emission sources. Urban concentrations in excess of regional baselines and intraurban variations of concentrations depend on source proximity, topography, and local meteorological processes. Regional-scale pollution events (95th percentile concentrations) involving more than 6 of the 8 SEARCH sites are rare (characterized by widely coincident elevated concentrations of ozone, sulfate, and particulate organic carbon, driven by persistent synoptic-scale air mass stagnation and higher temperatures that favor formation of secondary species, mainly in the summer months. The meteorological conditions associated with regional stagnation do not favor long-range transport of polluted air masses during episodes. Regional and subregional pollution events frequently terminate with southward and eastward penetration of frontal systems, which may initially reduce air pollutant concentrations more inland than along the Gulf Coast. Regional distribution of emission sources and synoptic-scale meteorological influences favoring stagnation lead to high

  15. The importance of evaluating the physicochemical and toxicological properties of a contaminant for remediating environments affected by chemical incidents.

    Science.gov (United States)

    Wyke, S; Peña-Fernández, A; Brooke, N; Duarte-Davidson, R

    2014-11-01

    In the event of a major chemical incident or accident, appropriate tools and technical guidance need to be available to ensure that a robust approach can be adopted for developing a remediation strategy. Remediation and restoration strategies implemented in the aftermath of a chemical incident are a particular concern for public health. As a result an innovative methodology has been developed to help design an effective recovery strategy in the aftermath of a chemical incident that has been developed; the UK Recovery Handbook for Chemical Incidents (UKRHCI). The handbook consists of a six-step decision framework and the use of decision trees specifically designed for three different environments: food production systems, inhabited areas and water environments. It also provides a compendium of evidence-based recovery options (techniques or methods for remediation) that should be selected in relation to their efficacy for removing contaminants from the environment. Selection of effective recovery options in this decision framework involves evaluating the physicochemical and toxicological properties of the chemical(s) involved. Thus, the chemical handbook includes a series of tables with relevant physicochemical and toxicological properties that should be assessed in function of the environment affected. It is essential that the physicochemical properties of a chemical are evaluated and interpreted correctly during the development of a remedial plan in the aftermath of a chemical incident to ensure an effective remedial response. This paper presents a general overview of the key physicochemical and toxicological properties of chemicals that should be evaluated when developing a recovery strategy. Information on how physicochemical properties have impacted on previous remedial responses reported in the literature is also discussed and a number of challenges for remediation are highlighted to include the need to develop novel approaches to remediate sites contaminated

  16. Chemical characteristics of soluble aerosols over the central Himalayas: insights into spatiotemporal variations and sources.

    Science.gov (United States)

    Tripathee, Lekhendra; Kang, Shichang; Rupakheti, Dipesh; Cong, Zhiyuan; Zhang, Qianggong; Huang, Jie

    2017-11-01

    In order to investigate the spatial and temporal variations of aerosols and its soluble chemical compositions of the data gap zone in the central Himalayan region, aerosol samples were collected at four sites. The sampling location were characterized by four different categories, such as urban (Bode), semi-urban site in the northern Indo-Gangetic Plain (Lumbini), rural (Dhunche), and semiarid rural (Jomsom). A total of 230 aerosol samples were collected from four representative sites for a yearlong period and analyzed for water-soluble inorganic ions (WSIIs). The annual average aerosol mass concentration followed the sequence as Bode (238.24 ± 162.24 μg/m3)> Lumbini (161.14 ± 105.95 μg/m3)> Dhunche (112.40 ± 40.30 μg/m3)> Jomsom (78.85 ± 34.28 μg/m3), suggesting heavier particulate pollution in the urban and semi-urban sites. The total soluble ions contributed to 12.61-28.19% of TSP aerosol mass. The results revealed that SO42- and NO3- were the major anion and Ca2+ and NH4+ were the major cation influencing the aerosol composition over the central Himalayas. Calcium played a major role in neutralizing aerosol acidity followed by NH4+ at all the sites. The major compound of aerosol was (NH4)2SO4 and NH4HSO4 in the central Himalayas. Clear seasonality was observed at three observation sites, with higher concentrations during non-monsoon (dry periods) and lower during monsoon (wet period), suggesting washing out of aerosol particles by heavy precipitation during monsoon. In contrast, semiarid sites did not show the clear seasonal trend due to limited precipitation. Stationary sources were predominant over the mobile sources mostly in the remote sites. Principal component analysis confirmed that the major sources of WSIIs in the region were industrial emissions, fossil fuel and biomass burning, and crustal fugitive dusts. Nevertheless, transboundary aerosol transport over the region from polluted cities from south Asia could not be ignored as

  17. Chemically engineering ligand selectivity at the free fatty acid receptor 2 based on pharmacological variation between species orthologs

    DEFF Research Database (Denmark)

    Hudson, Brian D; Christiansen, Elisabeth; Tikhonova, Irina G

    2012-01-01

    of the free fatty acid receptor 2 (FFA2) could be developed on the basis of pharmacological variation between species orthologs. For this, bovine FFA2 was characterized, revealing distinct ligand selectivity compared with human FFA2. Homology modeling and mutational analysis demonstrated a single mutation...... in human FFA2 of C4.57G resulted in a human FFA2 receptor with ligand selectivity similar to the bovine receptor. This was exploited to generate human FFA2-RASSL by the addition of a second mutation at a known orthosteric ligand interaction site, H6.55Q. The resulting FFA2-RASSL displayed a >100-fold loss...... on this receptor and demonstrates that exploitation of pharmacological variation between species orthologs is a powerful method to generate novel chemically engineered GPCRs.-Hudson, B. D., Christiansen, E., Tikhonova, I. G., Grundmann, M., Kostenis, E., Adams, D. R., Ulven, T., Milligan, G. Chemically engineering...

  18. Variation in global chemical composition of PM2.5: emerging results from SPARTAN

    Directory of Open Access Journals (Sweden)

    G. Snider

    2016-08-01

    black carbon ranged from 0.7 µg m−3 (Mammoth Cave to over 8 µg m−3 (Dhaka, Bangladesh and Kanpur, India. Comparison of SPARTAN vs. coincident measurements from the Interagency Monitoring of Protected Visual Environments (IMPROVE network at Mammoth Cave yielded a high degree of consistency for daily PM2.5 (r2 = 0.76, slope  =  1.12, daily sulfate (r2 = 0.86, slope  =  1.03, and mean fractions of all major PM2.5 components (within 6 %. Major ions generally agree well with previous studies at the same urban locations (e.g. sulfate fractions agree within 4 % for 8 out of 11 collocation comparisons. Enhanced anthropogenic dust fractions in large urban areas (e.g. Singapore, Kanpur, Hanoi, and Dhaka are apparent from high Zn : Al ratios.The expected water contribution to aerosols is calculated via the hygroscopicity parameter κv for each filter. Mean aggregate values ranged from 0.15 (Ilorin to 0.28 (Rehovot. The all-site parameter mean is 0.20 ± 0.04. Chemical composition and water retention in each filter measurement allows inference of hourly PM2.5 at 35 % relative humidity by merging with nephelometer measurements. These hourly PM2.5 estimates compare favourably with a beta attenuation monitor (MetOne at the nearby US embassy in Beijing, with a coefficient of variation r2 =  0.67 (n =  3167, compared to r2 = 0.62 when κv was not considered. SPARTAN continues to provide an open-access database of PM2.5 compositional filter information and hourly mass collected from a global federation of instruments.

  19. Variation in Global Chemical Composition of PM2.5: Emerging Results from SPARTAN

    Science.gov (United States)

    Snider, Graydon; Weagle, Crystal L.; Murdymootoo, Kalaivani K.; Ring, Amanda; Ritchie, Yvonne; Stone, Emily; Walsh, Ainsley; Akoshile, Clement; Anh, Nguyen Xuan; Balasubramanian, Rajasekhar; hide

    2016-01-01

    cubic meter (Buenos Aires, Argentina) to 17 microns per cubic meter (Kanpur, India in the dry season). Ammonium nitrate ranged from 0.2 microns per cubic meter (Mammoth Cave, in summer) to 6.8 microns per cubic meter (Kanpur, dry season). Equivalent black carbon ranged from 0.7 microns per cubic meter (Mammoth Cave) to over 8 microns per cubic meter (Dhaka, Bangladesh and Kanpur, India). Comparison of SPARTAN vs. coincident measurements from the Interagency Monitoring of Protected Visual Environments (IMPROVE) network at Mammoth Cave yielded a high degree of consistency for daily PM (sub 2.5) (r squared equals 0.76, slope equals 1.12), daily sulfate (r squared equals 0.86, slope equals 1.03), and mean fractions of all major PM (sub 2.5) components (within 6 percent). Major ions generally agree well with previous studies at the same urban locations (e.g. sulfate fractions agree within 4 percent for 8 out of 11 collocation comparisons). Enhanced anthropogenic dust fractions in large urban areas (e.g. Singapore, Kanpur, Hanoi, and Dhaka) are apparent from high Zn to Al ratios. The expected water contribution to aerosols is calculated via the hygroscopicity parameter kappa (sub v (volume)) for each filter. Mean aggregate values ranged from 0.15 (Ilorin) to 0.28 (Rehovot). The all-site parameter mean is 0.20 plus or minus 0.04. Chemical composition and water retention in each filter measurement allows inference of hourly PM (sub 2.5) at 35 percent relative humidity by merging with nephelometer measurements. These hourly PM (sub 2.5) estimates compare favourably with a beta attenuation monitor (MetOne) at the nearby US embassy in Beijing, with a coefficient of variation r squared equals 0.67 (number equals 3167), compared to r squared equals 0.62 when v (volume) was not considered. SPARTAN continues to provide an open-access database of PM (sub 2.5) compositional filter information and hourly mass collected from a global federation of instruments.

  20. Variation Theory: A Theory of Learning and a Useful Theoretical Framework for Chemical Education Research

    Science.gov (United States)

    Bussey, Thomas J.; Orgill, MaryKay; Crippen, Kent J.

    2013-01-01

    Instructors are constantly baffled by the fact that two students who are sitting in the same class, who have access to the same materials, can come to understand a particular chemistry concept differently. Variation theory offers a theoretical framework from which to explore possible variations in experience and the resulting differences in…

  1. Greater variation in affect is associated with lower fasting plasma glucose

    Directory of Open Access Journals (Sweden)

    Sunjai Gupta

    2016-09-01

    Conclusion: This study has shown an inverse association between changes in affect and fasting plasma glucose. This unexpected finding suggests that the association between affect and glucose is more complex than previously thought. Fasting blood glucose may reflect the operation of homeostatic mechanisms that are disturbed in certain mental states and are associated, therefore, with altered risk of diabetes and related metabolic conditions. This may have implications for the management of those with such conditions and with mental disorders.

  2.     Developmental acclimation affects clinal variation in stress resistance traits in Drosophila buzzatii

    DEFF Research Database (Denmark)

    Sarup, Pernille Merete; Loeschcke, Volker

    2010-01-01

      Patterns of clinal genetic variation in Drosophila are often characterized after rearing at constant temperatures. However, clinal patterns might change after acclimation if populations differ in their plastic response to fluctuating environments. We studied longevity, starvation and heat knock...... temperatures, especially in heat knock-down, for which clinal patterns disappeared when flies were reared at constant temperatures. This result emphasises the importance of determining whether populations originating from different environments differ in their plastic responses to stress....

  3. Time-Dependent Behavior of Shrinkage Strain for Early Age Concrete Affected by Temperature Variation

    Directory of Open Access Journals (Sweden)

    Yu Qin

    2017-01-01

    Full Text Available Shrinkage has been proven to be an important property of early age concrete. The shrinkage strain leads to inherent engineering problems, such as cracking and loss of prestress. Atmospheric temperature is an important factor in shrinkage strain. However, current research does not provide much attention to the effect of atmospheric temperature on shrinkage of early age concrete. In this paper, a laboratory study was undertaken to present the time-dependent shrinkage of early age concrete under temperature variation. A newly developed Material Deformation Tester (MDT, which can simulate consecutive variation of atmospheric temperature, was used to collect the shrinkage strain of specimens and temperature data. A numerical model was established to describe the thermoelastic strain of a specimen. The results show that (1 there are several sharp shrinkages up to 600 μ for early age concrete in the first 3 days; (2 the absolute value of shrinkage strain is larger than thermal strain; and (3 the difference of shrinkage strain under temperature variation or constant temperature is up to 500 μ.

  4. Habitat variation and wing coloration affect wing shape evolution in dragonflies.

    Science.gov (United States)

    Outomuro, D; Dijkstra, K-D B; Johansson, F

    2013-09-01

    Habitats are spatially and temporally variable, and organisms must be able to track these changes. One potential mechanism for this is dispersal by flight. Therefore, we would expect flying animals to show adaptations in wing shape related to habitat variation. In this work, we explored variation in wing shape in relation to preferred water body (flowing water or standing water with tolerance for temporary conditions) and landscape (forested to open) using 32 species of dragonflies of the genus Trithemis (80% of the known species). We included a potential source of variation linked to sexual selection: the extent of wing coloration on hindwings. We used geometric morphometric methods for studying wing shape. We also explored the phenotypic correlation of wing shape between the sexes. We found that wing shape showed a phylogenetic structure and therefore also ran phylogenetic independent contrasts. After correcting for the phylogenetic effects, we found (i) no significant effect of water body on wing shape; (ii) male forewings and female hindwings differed with regard to landscape, being progressively broader from forested to open habitats; (iii) hindwings showed a wider base in wings with more coloration, especially in males; and (iv) evidence for phenotypic correlation of wing shape between the sexes across species. Hence, our results suggest that natural and sexual selection are acting partially independently on fore- and hindwings and with differences between the sexes, despite evidence for phenotypic correlation of wing shape between males and females. © 2013 The Authors. Journal of Evolutionary Biology © 2013 European Society For Evolutionary Biology.

  5. Variations in chemical fingerprints and major flavonoid contents from the leaves of thirty‐one accessions of Hibiscus sabdariffa L.

    Science.gov (United States)

    Wang, Jin; Cao, Xianshuang; Ferchaud, Vanessa; Jiang, Hao; Tang, Feng; Chin, Kit L.

    2015-01-01

    Abstract The leaves of Hibiscus sabdariffa L. have been used as traditional folk medicines for treating high blood pressure and fever. There are many accessions of H. sabdariffa L. throughout the world. To assess the chemical variations of 31 different accessions of H. sabdariffa L., fingerprinting analysis and quantitation of major flavonoids were performed by high‐performance liquid chromatography (HPLC). The HPLC method was validated for linearity, sensitivity, precision, repeatability and accuracy. A quadrupole‐time‐of‐flight mass spectrometry (Q‐TOF‐MS) was applied for the characterization of major compounds. A total of 9 compounds were identified, including 6 flavonoids and 3 phenolic acids. In the fingerprint analysis, similarity analysis (SA) and principal component analysis (PCA) were used to differentiate the 31 accessions of H. sabdariffa L. Based on the results of PCA and SA, the samples No. 15 and 19 appeared much different from the main group. The total content of five flavonoids varied greatly among different accessions, ranging from 3.35 to 23.30 mg/g. Rutin was found to be the dominant compound and the content of rutin could contribute to chemical variations among different accessions. This study was helpful to understand the chemical variations between different accessions of H. sabdariffa L., which could be used for quality control. © 2015 The Authors Biomedical Chromatography Published by John Wiley & Sons Ltd. PMID:26394363

  6. Variations in chemical fingerprints and major flavonoid contents from the leaves of thirty-one accessions of Hibiscus sabdariffa L.

    Science.gov (United States)

    Wang, Jin; Cao, Xianshuang; Ferchaud, Vanessa; Qi, Yadong; Jiang, Hao; Tang, Feng; Yue, Yongde; Chin, Kit L

    2016-06-01

    The leaves of Hibiscus sabdariffa L. have been used as traditional folk medicines for treating high blood pressure and fever. There are many accessions of H. sabdariffa L. throughout the world. To assess the chemical variations of 31 different accessions of H. sabdariffa L., fingerprinting analysis and quantitation of major flavonoids were performed by high-performance liquid chromatography (HPLC). The HPLC method was validated for linearity, sensitivity, precision, repeatability and accuracy. A quadrupole-time-of-flight mass spectrometry (Q-TOF-MS) was applied for the characterization of major compounds. A total of 9 compounds were identified, including 6 flavonoids and 3 phenolic acids. In the fingerprint analysis, similarity analysis (SA) and principal component analysis (PCA) were used to differentiate the 31 accessions of H. sabdariffa L. Based on the results of PCA and SA, the samples No. 15 and 19 appeared much different from the main group. The total content of five flavonoids varied greatly among different accessions, ranging from 3.35 to 23.30 mg/g. Rutin was found to be the dominant compound and the content of rutin could contribute to chemical variations among different accessions. This study was helpful to understand the chemical variations between different accessions of H. sabdariffa L., which could be used for quality control. © 2015 The Authors Biomedical Chromatography Published by John Wiley & Sons Ltd. © 2015 The Authors Biomedical Chromatography Published by John Wiley & Sons Ltd.

  7. Effect of Gap Size on Seasonal Variation of Soil Chemical Properties in Subtropical Forest, Southern China

    National Research Council Canada - National Science Library

    Supaporn Buajan; Liu JinFu; He ZhongSheng; Abrar Muhammad

    2017-01-01

    Gap area has an effect on the soil chemical properties. To find out whatever the effect of gap area on the soil chemical properties, gap area was divided into small, medium, and large gap sizes and under the canopy as control...

  8. Chemical speciation in mining affected waters: the case study of Asarel-Medet mine.

    Science.gov (United States)

    Rabadjieva, Diana; Tepavitcharova, Stefka; Todorov, Tihomir; Dassenakis, Manos; Paraskevopoulou, Vasiliki; Petrov, Mihail

    2009-12-01

    The inorganic chemical species in Maresh and Luda Yana rivers affected by the Cu- Mo Asarel-Medet mine, Bulgaria were determined during a low-flow and a high-flow period. The mining activities, the weathering and the oxidation processes strongly influenced the physicochemical processes in the whole water system. The main pollution source was a small lake receiving the acid effluents of the mining activities. High levels of SO4(2-), Cu, Mg, Al, Mn and Fe were determined at the mining polluted and affected stations. Cu(2+) and CuCO3(0) species (1:1) were present in the reference waters and Cu(2+) and CuSO4(0) species (1:1) in the polluted and affected waters; Cu(2+) species was dominating downstream. Me(2+) followed by MeSO4(0) (Me = Mn, Zn, Cd and Pb), PbCO3(0) and PbHCO3(+) species as well as Fe(OH)2(+), Al(OH)4(-), Al(OH)2(+), Al(OH)3(0) were prevailing in the system. MeSO4(+) and Me(SO4)2(-) (Me = Fe, Al), Me(SO4)2(2-) (Me = Zn, Cd and Pb), Me(SO4)3(4-) (Me = Zn, Cd) and Cd(SO4)4(6-) species polluted and affected waters. The major elements K and Na were mainly Me(+) species, whereas Ca and Mg were Me(2+) and MeSO4(0) species in different ratios. The concentration of concentration of NO2(-), NO3(-) and NO4(+) species as well as complex phosphorous species such as H2PO4(-), FeHPO4(+), HPO4(2-), CaPO4(-), CaHPO4(0) and MgHPO4(0) were also calculated. The trace element concentrations decreased downstream due to dilution, sorption processes and precipitation, but the percentage of free metal species, which are more toxic, increased. An exception was iron and aluminum of which the dominant hydroxy colloidal and sulphate species were easily incorporated into the suspended phase.

  9. Seasonal variations of antimicrobial activity and chemical composition of essential oils extracted from three Citrus limon L. Burm. cultivars.

    Science.gov (United States)

    Settanni, L; Randazzo, W; Palazzolo, E; Moschetti, M; Aleo, A; Guarrasi, V; Mammina, C; San Biagio, P L; Marra, F P; Moschetti, G; Germanà, M A

    2014-01-01

    In order to investigate the seasonal variations of antimicrobial properties and chemical composition of essential oils (EOs), three different cultivars of Citrus limon L. Burm. spp. (Femminello Santa Teresa, Monachello and Femminello Continella) were collected at 6-week intervals, from December 2012 to April 2013, for a total of four harvests. The EOs were extracted from lemon peel by hydro-distillation. The antimicrobial activity, tested by paper disc diffusion method, was evaluated against common food-related pathogenic bacteria (Listeria monocytogenes, Staphylococcus aureus, Salmonella enterica and Enterobacter spp.). EOs were more effective against Gram-positive than Gram-negative bacteria at each collection time, but a strong strain dependence was evidenced. Monachello EOs showed the highest inhibition power. The chemical characterisation of the EOs performed by gas chromatography/mass spectrometry identified from 36 to 42 molecules. The chemical difference registered among samples and seasons may explain the different antimicrobial efficacies recorded.

  10. DPP4 gene variation affects GLP-1 secretion, insulin secretion, and glucose tolerance in humans with high body adiposity

    DEFF Research Database (Denmark)

    Böhm, Anja; Wagner, Robert; Machicao, Fausto

    2017-01-01

    , inter-individual variance in the responsiveness to DPP-4 inhibitors was reported. Thus, we asked whether genetic variation in the DPP4 gene affects incretin levels, insulin secretion, and glucose tolerance in participants of the TÜbingen Family study for type-2 diabetes (TÜF). RESEARCH DESIGN......-BMI interaction effects were detected (p = 0.8). After stratification for body fat content, the SNP negatively affected glucose-stimulated GLP-1 levels (p = 0.0229), insulin secretion (p = 0.0061), and glucose tolerance (p = 0.0208) in subjects with high body fat content only. CONCLUSIONS: A common variant, i.......e., SNP rs6741949, in the DPP4 gene interacts with body adiposity and negatively affects glucose-stimulated GLP-1 levels, insulin secretion, and glucose tolerance. Whether this SNP underlies the reported inter-individual variance in responsiveness to DPP-4 inhibitors, at least in subjects with high body...

  11. How Do Aerosol Properties Affect the Temporal Variation of MODIS AOD Bias in Eastern China?

    Directory of Open Access Journals (Sweden)

    Minghui Tao

    2017-08-01

    Full Text Available The rapid changes of aerosol sources in eastern China during recent decades could bring considerable uncertainties for satellite retrieval algorithms that assume little spatiotemporal variation in aerosol single scattering properties (such as single scattering albedo (SSA and the size distribution for fine-mode and coarse mode aerosols in East Asia. Here, using ground-based observations in six AERONET sites, we characterize typical aerosol optical properties (including their spatiotemporal variation in eastern China, and evaluate their impacts on Moderate Resolution Imaging Spectroradiometer (MODIS Collection 6 aerosol retrieval bias. Both the SSA and fine-mode particle sizes increase from northern to southern China in winter, reflecting the effect of relative humidity on particle size. The SSA is ~0.95 in summer regardless of the AEROENT stations in eastern China, but decreases to 0.85 in polluted winter in northern China. The dominance of larger and highly scattering fine-mode particles in summer also leads to the weakest phase function in the backscattering direction. By focusing on the analysis of high aerosol optical depth (AOD (>0.4 conditions, we find that the overestimation of the AOD in Dark Target (DT retrieval is prevalent throughout the whole year, with the bias decreasing from northern China, characterized by a mixture of fine and coarse (dust particles, to southern China, which is dominated by fine particles. In contrast, Deep Blue (DB retrieval tends to overestimate the AOD only in fall and winter, and underestimates it in spring and summer. While the retrievals from both the DT and DB algorithms show a reasonable estimation of the fine-mode fraction of AOD, the retrieval bias cannot be attributed to the bias in the prescribed SSA alone, and is more due to the bias in the prescribed scattering phase function (or aerosol size distribution in both algorithms. In addition, a large yearly change in aerosol single scattering properties

  12. Morphological variation of the anterior inferior iliac spine affects hip range of motion in flexion after rotational acetabular osteotomy.

    Science.gov (United States)

    Hamada, Hidetoshi; Takao, Masaki; Sakai, Takashi; Sugano, Nobuhiko

    2017-10-28

    Reduced range of motion (ROM) in flexion and internal rotation are associated with impaired activities of daily living (ADL) after rotational acetabular osteotomy (RAO). This study focused on the morphological variation of the anterior inferior iliac spine in developmental dysplasia of the hip (DDH) and its impact on post-operative bony ROM after RAO. This study aimed to investigate the association between bony ROM after RAO and pre-operative morphological factors of the pelvis and femur, including a positional variation of the anterior inferior iliac spine. Bony ROM in 52 patients with DDH was assessed after virtual RAO using computed tomography (CT). Post-operative acetabular coverage was set at lateral and anterior centre-edge angles of 30° and 55°, respectively. The position of the anterior inferior iliac spine was classified as higher or lower. Multiple regression analysis revealed that the lower anterior inferior iliac spine and higher femoral neck shaft angle were significantly associated with the lower flexion angle after RAO. Lower femoral anteversion, higher femoral neck shaft angle and higher alpha angle at the anterosuperior part were significantly associated with lower internal rotation angle at 90° flexion after RAO. Therefore, morphological variation of the anterior inferior iliac spine affected bony ROM in flexion and that of the femoral neck affected bony ROM in internal rotation at flexion after RAO.

  13. Chemical variations in Yellowknife Bay formation sedimentary rocks analyzed by ChemCam on board the Curiosity rover on Mars

    Science.gov (United States)

    Mangold, Nicolas; Forni, Olivier; Dromart, G.; Stack, K.M.; Wiens, Roger C.; Gasnault, Olivier; Sumner, Dawn Y.; Nachon, Marion; Meslin, Pierre-Yves; Anderson, Ryan B.; Barraclough, Bruce; Bell, J.F.; Berger, G.; Blaney, D.L.; Bridges, J.C.; Calef, F.; Clark, Brian R.; Clegg, Samuel M.; Cousin, Agnes; Edgar, L.; Edgett, Kenneth S.; Ehlmann, B.L.; Fabre, Cecile; Fisk, M.; Grotzinger, John P.; Gupta, S.C.; Herkenhoff, Kenneth E.; Hurowitz, J.A.; Johnson, J. R.; Kah, Linda C.; Lanza, Nina L.; Lasue, Jeremie; Le Mouélic, S.; Lewin, Eric; Malin, Michael; McLennan, Scott M.; Maurice, S.; Melikechi, Noureddine; Mezzacappa, Alissa; Milliken, Ralph E.; Newsome, H.L.; Ollila, A.; Rowland, Scott K.; Sautter, Violaine; Schmidt, M.E.; Schroder, S.; D'Uston, C.; Vaniman, Dave; Williams, R.A.

    2015-01-01

    The Yellowknife Bay formation represents a ~5 m thick stratigraphic section of lithified fluvial and lacustrine sediments analyzed by the Curiosity rover in Gale crater, Mars. Previous works have mainly focused on the mudstones that were drilled by the rover at two locations. The present study focuses on the sedimentary rocks stratigraphically above the mudstones by studying their chemical variations in parallel with rock textures. Results show that differences in composition correlate with textures and both manifest subtle but significant variations through the stratigraphic column. Though the chemistry of the sediments does not vary much in the lower part of the stratigraphy, the variations in alkali elements indicate variations in the source material and/or physical sorting, as shown by the identification of alkali feldspars. The sandstones contain similar relative proportions of hydrogen to the mudstones below, suggesting the presence of hydrous minerals that may have contributed to their cementation. Slight variations in magnesium correlate with changes in textures suggesting that diagenesis through cementation and dissolution modified the initial rock composition and texture simultaneously. The upper part of the stratigraphy (~1 m thick) displays rocks with different compositions suggesting a strong change in the depositional system. The presence of float rocks with similar compositions found along the rover traverse suggests that some of these outcrops extend further away in the nearby hummocky plains.

  14. Variation in timing of ossification affects inferred heterochrony of cranial bones in Lissamphibia.

    Science.gov (United States)

    Sheil, Christopher A; Jorgensen, Michael; Tulenko, Frank; Harrington, Sean

    2014-09-01

    The evolutionary origin of Lissamphibia likely involved heterochrony, as demonstrated by the biphasic lifestyles of most extant orders, differences between Anura (with tadpole-to-froglet metamorphosis) and Urodela (which lack strongly defined metamorphosis), and the appearance of direct development among separate lineages of frogs. Patterns in the timing of appearance of skeletal elements (i.e., ossification sequence data) represent a possible source of information for understanding the origin of Lissamphibia, and with the advent of analytical methods to directly optimize these data onto known phylogenies, there has been a renewed interest in assessing the role of changes in these developmental events. However, little attention has been given to the potential impact of variation in ossification sequence data--this is particularly surprising given that different criteria for collecting these data have been employed. Herein, new and previously published ossification data are compiled and all pairs of data for same-species comparisons are selected. Analyses are run to assess the impact of using data that were collected by different methodologies: (1) wild- versus lab-raised animals; (2) different criteria for recognizing timing of ossification; and (3) randomly selecting ossification sequences for species from which multiple studies have been published, but for which the data were collected by different criteria. Parsimov-based genetic inference is utilized to map ossification sequence data onto an existing phylogeny to reconstruct ancestral sequences of ossification and infer instances of heterochrony. All analyses succeeded in optimizing sequence data on internal nodes and instances of heterochrony were identified. However, among all analyses little congruence was found in reconstructed ancestral sequences or among inferred instances of heterochrony. These results indicate a high degree of variation in timing of ossification, and suggest a cautionary note about use

  15. Seasonal variation in the chemical composition and carbohydrate signature compounds of biofilm

    Digital Repository Service at National Institute of Oceanography (India)

    DeSouza, F.P.; Garg, A.; Bhosle, N.B.

    Biofilm developed on stainless steel was characterised using biological, chemical and biochemical parameters, as well as aldose molecular biomarkers. Biofilm biomass and carbohydrate concentration increased on stainless steel, whereas C...

  16. Seasonal variations in diet selection of Nguni goats: effects of physical and chemical traits of browse

    CSIR Research Space (South Africa)

    Fomum, SW

    2015-05-01

    Full Text Available Goats select some browse species more than others, given options. Seasonal trends of diet selection of Nguni goats indexed by intake were investigated in cafeteria-style experiments. The relationships between diet selection and plant chemical...

  17. Enhanced Geothermal Systems Research and Development: Models of Subsurface Chemical Processes Affecting Fluid Flow

    Energy Technology Data Exchange (ETDEWEB)

    Moller, Nancy; Weare J. H.

    2008-05-29

    /or injected fluids is critical to predict important chemical behaviors affecting fluid flow, such as mineral precipitation/dissolution reactions. We successfully achieved the project goal and objectives by demonstrating the ability of our modeling technology to correctly predict the complex pH dependent solution chemistry of the Al3+ cation and its hydrolysis species: Al(OH)2+, Al(OH)2+, Al(OH)30, and Al(OH)4- as well as the solubility of common aluminum hydroxide and aluminosilicate minerals in aqueous brines containing components (Na, K, Cl) commonly dominating hydrothermal fluids. In the sodium chloride system, where experimental data for model parameterization are most plentiful, the model extends to 300°C. Determining the stability fields of aluminum species that control the solubility of aluminum-containing minerals as a function of temperature and composition has been a major objective of research in hydrothermal chemistry.

  18. Pubertal onset in girls is strongly influenced by genetic variation affecting FSH action

    DEFF Research Database (Denmark)

    Hagen, Casper P; Sørensen, Kaspar; Aksglaede, Lise

    2014-01-01

    Age at pubertal onset varies substantially in healthy girls. Although genetic factors are responsible for more than half of the phenotypic variation, only a small part has been attributed to specific genetic polymorphisms identified so far. Follicle-stimulating hormone (FSH) stimulates ovarian...... follicle maturation and estradiol synthesis which is responsible for breast development. We assessed the effect of three polymorphisms influencing FSH action on age at breast deveopment in a population-based cohort of 964 healthy girls. Girls homozygous for FSHR -29AA (reduced FSH receptor expression......) entered puberty 7.4 (2.5-12.4) months later than carriers of the common variants FSHR -29GG+GA, p = 0.003. To our knowledge, this is the strongest genetic effect on age at pubertal onset in girls published to date....

  19. Natural selection affects multiple aspects of genetic variation at putatively peutral sites across the human genome

    DEFF Research Database (Denmark)

    Lohmueller, Kirk E; Albrechtsen, Anders; Li, Yingrui

    2011-01-01

    A major question in evolutionary biology is how natural selection has shaped patterns of genetic variation across the human genome. Previous work has documented a reduction in genetic diversity in regions of the genome with low recombination rates. However, it is unclear whether other summaries...... and that human diversity, human-chimp divergence, and average minor allele frequency are reduced near genes. Population genetic simulations show that either positive natural selection acting on favorable mutations or negative natural selection acting against deleterious mutations can explain these correlations...... throughout the genome. Further, we show that the widespread presence of weakly deleterious alleles, rather than a small number of strongly positively selected mutations, is responsible for the correlation between neutral genetic diversity and recombination rate. This work suggests that natural selection has...

  20. Lead, zinc, and chromium concentrations in acidic headwater streams in Sweden explained by chemical, climatic, and land-use variations

    Directory of Open Access Journals (Sweden)

    B. J. Huser

    2012-11-01

    Full Text Available Long-term data series (1996–2009 for eleven acidic headwater streams (< 10 km2 in Sweden were analyzed to determine factors controlling concentrations of trace metals. In-stream chemical data as well climatic, flow, and deposition chemistry data were used to develop models predicting concentrations of chromium (Cr, lead (Pb, and zinc (Zn. Data were initially analyzed using partial least squares to determine a set of variables that could predict metal concentrations across all sites. Organic matter (as absorbance and iron related positively to Pb and Cr, while pH related negatively to Pb and Zn. Other variables such as conductivity, manganese, and temperature were important as well. Multiple linear regression was then used to determine minimally adequate prediction models which explained an average of 35% (Cr, 52% (Zn, and 72% (Pb of metal variation across all sites. While models explained at least 50% of variation in the majority of sites for Pb (10 and Zn (8, only three sites met this criterion for Cr. Investigation of variation between site models for each metal revealed geographical (altitude, chemical (sulfate, and land-use (silvaculture influences on predictive power of the models. Residual analysis revealed seasonal differences in the ability of the models to predict metal concentrations as well. Expected future changes in model variables were applied and results showed the potential for long-term increases (Pb or decreases (Zn for trace metal concentrations at these sites.

  1. Influence of reactions heats on variation of radius, temperature, pressure and chemical species amounts within a single acoustic cavitation bubble.

    Science.gov (United States)

    Kerboua, Kaouther; Hamdaoui, Oualid

    2018-03-01

    The scientific interest toward the study of acoustic bubble is mainly explained by its practical benefit in providing a reactional media favorable to the rapid evolution of chemical mechanism. The evolution of this mechanism is related to the simultaneous and dependent variation of the volume, temperature and pressure within the bubble, retrieved by the resolution of a differential equations system, including among others the thermal balance. This last one is subject to different assumptions, some authors deem simply that the temperature varies adiabatically during the collapsing phase, without considering the reactions heat of the studied mechanism. This paper aims to evaluate the pertinence of neglecting reactions heats in the thermal balance, by analyzing their effect on the variation of radius, temperature, pressure and chemical species amounts. The results show that the introduction of reactions heats conducts to a decrease of the temperature, an increase of the pressure and a reduction of the bubble volume. As a consequence, this leads to a drop of the quantities of free radicals produced by the chemical mechanism evolving within the bubble. This paper also proved that the impact of the consideration of reactions heats is dependent of the frequency and the acoustic amplitude of the ultrasonic wave. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. An olfactory-limbic model of multiple chemical sensitivity syndrome: Possible relationships to kindling and affective spectrum disorders

    Energy Technology Data Exchange (ETDEWEB)

    Bell, I.R.; Miller, C.S.; Schwartz, G.E. (Univ. of Arizona Health Sciences Center, Tucson (United States))

    1992-08-01

    This paper reviews the clinical and experimental literature on patients with multiple adverse responses to chemicals (Multiple Chemical Sensitivity Syndrome-MCS) and develops a model for MCS based on olfactory-limbic system dysfunction that overlaps in part with Post's kindling model for affective disorders. MCS encompasses a broad range of chronic polysymptomatic conditions and complaints whose triggers are reported to include low levels of common indoor and outdoor environmental chemicals, such as pesticides and solvents. Other investigators have found evidence of increased prevalence of depression, anxiety, and somatization disorders in MCS patients and have concluded that their psychiatric conditions account for the clinical picture. However, none of these studies has presented any data on the effects of chemicals on symptoms or on objective measures of nervous system function. Synthesis of the MCS literature with large bodies of research in neurotoxicology, occupational medicine, and biological psychiatry, suggests that the phenomenology of MCS patients overlaps that of affective spectrum disorders and that both involve dysfunction of the limbic pathways. Animal studies demonstrate that intermittent repeated low level environmental chemical exposures, including pesticides, cause limbic kindling. Kindling (full or partial) is one central nervous system mechanism that could amplify reactivity to low levels of inhaled and ingested chemicals and initiate persistent affective, cognitive, and somatic symptomatology in both occupational and nonoccupational settings. As in animal studies, inescapable and novel stressors could cross-sensitize with chemical exposures in some individuals to generate adverse responses on a neurochemical basis. The olfactory-limbic model raises testable neurobiological hypotheses that could increase understanding of the multifactorial etiology of MCS and of certain overlapping affective spectrum disorders. 170 refs.

  3. Consequences of variations in genes that affect dopamine in prefrontal cortex.

    Science.gov (United States)

    Diamond, Adele

    2007-09-01

    Patricia Goldman-Rakic played a groundbreaking role in investigating the cognitive functions subserved by dorsolateral prefrontal cortex and the key role of dopamine in that. The work discussed here builds on that including: 1) Studies of children predicted to have lower levels of prefrontal dopamine but otherwise basically normal brains (children treated for phenylketonuria [PKU]). Those studies changed medical guidelines, improving the children's lives. 2) Studies of visual impairments (in contrast sensitivity and motion perception) in PKU children due to reduced retinal dopamine and due to excessive phenylalanine during the first postnatal weeks. Those studies, too, changed medical guidelines. 3) Studies of working memory and inhibitory control differences in typically developing children due to differences in catechol-O-methyltransferase (COMT) genotype, which selectively affect prefrontal dopamine levels. 4) Studies of gender differences in the effect of COMT genotype on cognitive performance in older adults. 5) A hypothesis about fundamental differences between attention deficit hyperactivity disorder (ADHD) that includes hyperactivity and ADHD of the inattentive type. Those disorders are hypothesized to differ in the affected neural system, underlying genetics, responsiveness to medication, comorbidities, and cognitive and behavioral profiles. These sound quite disparate but they all grew systematically out the base laid down by Patricia Goldman-Rakic.

  4. Negative affect is associated with development and persistence of chemical intolerance: a prospective population-based study.

    Science.gov (United States)

    Skovbjerg, Sine; Christensen, Karl Bang; Ebstrup, Jeanette Frost; Linneberg, Allan; Zachariae, Robert; Elberling, Jesper

    2015-05-01

    Chemical intolerance (CI) is characterised by negative health effects attributed to a heightened responsiveness to common airborne chemicals. This longitudinal study explored the hypothesised role of negative affect in the development and persistence of CI in a general population. A general population sample aged 19 to 72 years was examined in 2006-2008 and again in 2011-2012. Longitudinal data on CI were analysed with the purpose of examining baseline negative affect as a risk factor for having developed CI at 5-year follow-up and for reporting persistent CI. Participants were classified as reporting no signs of CI, having symptoms of CI and as being a likely CI case based on self-reported reactions to 11 common chemical exposures, symptoms related to chemical exposures and daily life adjustments attributed to reactions when exposed to chemicals. A total of 69.4% of the participants who had reported CI at baseline also reported CI at follow-up. In participants with no baseline CI, 15.5% reported CI at follow-up and 18.1% reported symptoms related to chemicals but no daily life adjustments. Baseline negative affect was positively and statistically significantly associated with both development and persistence of CI. Initial reports of CI were found to be persistent over time, and a considerable proportion of the participants with no CI at baseline reported having developed CI after 5 years. The positive association between negative affect and CI at the 5-year follow-up supports negative affect as a possible risk factor for CI. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Physical-Chemical Factors Affecting the Low Quality of Natural Water in the Khibiny Massif

    Science.gov (United States)

    Mazukhina, Svetlana; Masloboev, Vladimir; Chudnenko, Konstantin; Maksimova, Viktoriia; Belkina, Natalia

    2014-05-01

    One peculiarity of the Khibiny Massif is its spatial location. Rising over 1000 m above the surrounding hilly land and thus obstructing the passage of air masses, it promotes condensation and accumulation of surface and underground water. Annual precipitation here amounts to 600-700 mm in the valleys and up to 1600 mm on mountainous plateaus. Using this water for drinking and household purposes is problematic due to excess Al and F concentrations and high pH values. Now it is known that in its profile, the Massif is represented by three hydrogeological subzones: the upper (aerated), medium and lower ones. The upper subzone spreads throughout the Massif and is affected by the local drainage network and climatic conditions. The medium subzone is permanently saturated with underground water flowing horizontally to sites of discharge at the level of local river valleys and lakes. The fissure-vein water in the lower subzone is confined to tectonic fractures and faults in the so far underexplored, deeper parts of the Massif. Being abundant, this water ascends under high pressure. At places, water has been observed spurting from as deep as 700 m, and even 960 m. In the latter case, the temperature of ascending water was higher than 18 centigrade (Hydrogeology of the USSR, V. 27, 1971). This work was undertaken to reveal the nature of the low quality of water in the Khibiny by using physical-chemical modeling (software package Selector, Chudnenko, 2010). Processes of surface and underground water formation in the Khibiny were examined within a physical-chemical model (PCM) of the "water-rock-atmosphere-hydrogen" system. In a multi-vessel model used, each vessel represented a geochemical level of the process interpreted as spatiotemporal data - ξ (Karpov, 1981). The flow reactor consisted of 4 tanks. In the first tank, water of the Kuniok River (1000 L) interacted with atmosphere and an organic substance. The resulting solution proceeded to tanks 2-4 containing with

  6. The diversity of coral associated bacteria and the environmental factors affect their community variation.

    Science.gov (United States)

    Zhang, Yan-Ying; Ling, Juan; Yang, Qing-Song; Wang, You-Shao; Sun, Cui-Ci; Sun, Hong-Yan; Feng, Jing-Bin; Jiang, Yu-Feng; Zhang, Yuan-Zhou; Wu, Mei-Lin; Dong, Jun-De

    2015-10-01

    Coral associated bacterial community potentially has functions relating to coral health, nutrition and disease. Culture-free, 16S rRNA based techniques were used to compare the bacterial community of coral tissue, mucus and seawater around coral, and to investigate the relationship between the coral-associated bacterial communities and environmental variables. The diversity of coral associated bacterial communities was very high, and their composition different from seawater. Coral tissue and mucus had a coral associated bacterial community with higher abundances of Gammaproteobacteria. However, bacterial community in seawater had a higher abundance of Cyanobacteria. Different populations were also found in mucus and tissue from the same coral fragment, and the abundant bacterial species associated with coral tissue was very different from those found in coral mucus. The microbial diversity and OTUs of coral tissue were much higher than those of coral mucus. Bacterial communities of corals from more human activities site have higher diversity and evenness; and the structure of bacterial communities were significantly different from the corals collected from other sites. The composition of bacterial communities associated with same coral species varied with season's changes, geographic differences, and coastal pollution. Unique bacterial groups found in the coral samples from more human activities location were significant positively correlated to chemical oxygen demand. These coral specific bacteria lead to coral disease or adjust to form new function structure for the adaption of different surrounding needs further research.

  7. Verifying of endocrine disruptor chemical affect to the mouse testes: can raman spectroscopy support histology study?

    Science.gov (United States)

    Andriana, Bibin B.; Oshima, Yusuke; Takanezawa, Sota; Tay, Tat W.; Rosawati Soeratman, Catherine Linda; Alam, Mohammad S.; Mitsuoka, Hiroki; Zhu, Xiao B.; Suzuki, Toshiaki; Yamamoto, Yuko S.; Tsunekawa, Naoki; Kanai, Yoshiakira; Kurohmaru, Masamichi; Sato, Hidetoshi

    2009-02-01

    One of suspect environmental endocrine disruptors that affect mouse male reproduction by altering the morphology of Sertoli cells and spermatogenic cells is phthalate. The effects of mono(2-ethylhexyl)phthalate (MEHP), one of metabolites of di(2-ethylhexyl)phthalate , on immature mouse testes in vivo were examined. We have recently shown that MEHP induced Sertoli cells necrosis and spermatogenic cells apoptosis in mice by TUNEL method, F-actin staining, and ultrastructural study, but there is no data for biochemical changing of testes due to those methods could not explore. To verify in detail of it, we conducted Raman spectroscopy study with 785 nm wavelength laser line, 50mW of laser power and 3 minutes of exposure time to analysis the MEHP-treated testicular tissue, which has been fixatived by 4% paraformaldehyde (PFA). Five weeks old (5 w.o) male mice were used in this experiment. As the results, the alterations were observed by Raman spectroscopy that there are significantly differences of DNA, actin filament, type IV collagen and amide I between control group (0 μM MEHP) and treatment group (100 μM MEHP). These results significantly support histology staining observation (such as the apoptotic spermatogenic cells which is associated with DNA fragmentation and F-actin disruption) and ultrastructural observation (such as mitochondria rupture and disintegration of nucleus membrane). Raman spectroscopy can be used for 4% PFA-fixatived tissue observation. However, we recommend that Raman spectroscopy may be able to be expanded as an armamentarium not just for the clarification of histology staining and ultrastructural study, but furthermore, it may be as a non-invasion assessment for screening animal tissue toxicity of chemical in future.

  8. Neural plasticity is affected by stress and heritable variation in stress coping style

    DEFF Research Database (Denmark)

    Johansen, I.B.; Sørensen, C.; Sandvik, G.K.

    2012-01-01

    Here we use a comparative model to investigate how behavioral and physiological traits correlate with neural plasticity. Selection for divergent post-stress cortisol levels in rainbow trout (Oncorhynchus mykiss) has yielded low- (LR) and high responsive (HR) lines. Recent reports show low...... behavioral flexibility in LR compared to HR fish and we hypothesize that this divergence is caused by differences in neural plasticity. Genes involved in neural plasticity and neurogenesis were investigated by quantitative PCR in brains of LR and HR fish at baseline conditions and in response to two...... also being affected by STC – and LTS stress in a biphasic manner. A higher degree of neural plasticity in HR fish may provide the substrate for enhanced behavioral flexibility...

  9. How does variation in rainfall affect simulated tropical tree mortality, functional diversity and coexistence?

    Science.gov (United States)

    Powell, T.; Kueppers, L. M.; Koven, C.; Johnson, D. J.; Faybishenko, B.; McDowell, N. G.; Chambers, J. Q.

    2016-12-01

    Land surface models that include demographic and plant hydrodynamic processes are promising tools for characterizing how different drought scenarios may affect carbon cycling of tropical forests. The Ecosystem Demography (ED2) model, now formulated with such features, was used to evaluate how different drought scenarios affect mortality patterns, functional diversity and coexistence of four plant functional types (PFTs) of tropical trees at Barro Colorado Island (BCI), Panama. The four PFTs simulated were early- versus late-successional groups subdivided into drought-tolerant versus -intolerant groups. The hydrodynamic formulation enables the four PFTs to compete mechanistically along two largely orthogonal resource gradients of water and light. The model simulations produced considerable differences in the aboveground biomass response to contrasting drying scenarios that included longer dry seasons, El Nino related droughts, and drier dry seasons. The emergent mortality dynamics reflect the physiological trade-off between water-use and carbon fixation formulated by the hydrodynamic regulation over stomatal conductance. During dry periods, the model predicts increased mortality rates of pioneer trees compared to generalists and drought-intolerant trees compared to -tolerant trees. The model also predicts that surviving cohorts in the smallest size classes of drought-intolerant trees are occasionally primed for release from competition following acute droughts. Observations at BCI showed increased mortality rates for large trees (i.e. >30 cm dbh) during the 1982 El Nino drought, but not subsequent El Nino related droughts. The causes of the elevated mortality rates are explored with the model. Coexistence of four plant functional types in the model is highly sensitive to the parameterization of stem hydraulic conductivity; but, surprisingly not very sensitive to shifts in rainfall patterns. These results demonstrate (a) that plant hydrodynamics are critical for

  10. Nature, evolution and characterisation of rhizospheric chemical exudates affecting root herbivores

    OpenAIRE

    Hiltpold Ivan; Bernklau Elisa Jo; Bjostad Louis B.; Alvarez Nadir; Miller-Struttmann Nicole E.; Lundgren Jonathan G.; Hibbard Bruce E.

    2013-01-01

    Similar to aboveground herbivores root feeding insects must locate and identify suitable resources. In the darkness of soil they mainly rely on root chemical exudations and therefore have evolved specific behaviours. Because of their impact on crop yield most of our knowledge in belowground chemical ecology is biased towards soil dwelling insect pests. Yet the increasing literature on volatile mediated interactions in the ground underpins the great importance of chemical signalling in this ec...

  11. Genetic variation of the RASGRF1 regulatory region affects human hippocampus-dependent memory

    Directory of Open Access Journals (Sweden)

    Adriana eBarman

    2014-04-01

    Full Text Available The guanine nucleotide exchange factor RASGRF1 is an important regulator of intracellular signaling and neural plasticity in the brain. RASGRF1-deficient mice exhibit a complex phenotype with learning deficits and ocular abnormalities. Also in humans, a genome-wide association study has identified the single nucleotide polymorphism (SNP rs8027411 in the putative transcription regulatory region of RASGRF1 as a risk variant of myopia. Here we aimed to assess whether, in line with the RASGRF1 knockout mouse phenotype, rs8027411 might also be associated with human memory function. We performed computer-based neuropsychological learning experiments in two independent cohorts of young, healthy participants. Tests included the Verbal Learning and Memory Test (VLMT and the logical memory section of the Wechsler Memory Scale (WMS. Two sub-cohorts additionally participated in functional magnetic resonance imaging (fMRI studies of hippocampus function. 119 participants performed a novelty encoding task that had previously been shown to engage the hippocampus, and 63 subjects participated in a reward-related memory encoding study. RASGRF1 rs8027411 genotype was indeed associated with memory performance in an allele dosage-dependent manner, with carriers of the T allele (i.e. the myopia risk allele showing better memory performance in the early encoding phase of the VLMT and in the recall phase of the WMS logical memory section. In fMRI, T allele carriers exhibited increased hippocampal activation during presentation of novel images and during encoding of pictures associated with monetary reward. Taken together, our results provide evidence for a role of the RASGRF1 gene locus in hippocampus-dependent memory and, along with the previous association with myopia, point towards pleitropic effects of RASGRF1 genetic variations on complex neural function in humans.

  12. Genetic variation of the RASGRF1 regulatory region affects human hippocampus-dependent memory

    Science.gov (United States)

    Barman, Adriana; Assmann, Anne; Richter, Sylvia; Soch, Joram; Schütze, Hartmut; Wüstenberg, Torsten; Deibele, Anna; Klein, Marieke; Richter, Anni; Behnisch, Gusalija; Düzel, Emrah; Zenker, Martin; Seidenbecher, Constanze I.; Schott, Björn H.

    2014-01-01

    The guanine nucleotide exchange factor RASGRF1 is an important regulator of intracellular signaling and neural plasticity in the brain. RASGRF1-deficient mice exhibit a complex phenotype with learning deficits and ocular abnormalities. Also in humans, a genome-wide association study has identified the single nucleotide polymorphism (SNP) rs8027411 in the putative transcription regulatory region of RASGRF1 as a risk variant of myopia. Here we aimed to assess whether, in line with the RASGRF1 knockout mouse phenotype, rs8027411 might also be associated with human memory function. We performed computer-based neuropsychological learning experiments in two independent cohorts of young, healthy participants. Tests included the Verbal Learning and Memory Test (VLMT) and the logical memory section of the Wechsler Memory Scale (WMS). Two sub-cohorts additionally participated in functional magnetic resonance imaging (fMRI) studies of hippocampus function. 119 participants performed a novelty encoding task that had previously been shown to engage the hippocampus, and 63 subjects participated in a reward-related memory encoding study. RASGRF1 rs8027411 genotype was indeed associated with memory performance in an allele dosage-dependent manner, with carriers of the T allele (i.e., the myopia risk allele) showing better memory performance in the early encoding phase of the VLMT and in the recall phase of the WMS logical memory section. In fMRI, T allele carriers exhibited increased hippocampal activation during presentation of novel images and during encoding of pictures associated with monetary reward. Taken together, our results provide evidence for a role of the RASGRF1 gene locus in hippocampus-dependent memory and, along with the previous association with myopia, point toward pleitropic effects of RASGRF1 genetic variations on complex neural function in humans. PMID:24808846

  13. Screening for chemicals that affect hair cell death and survival in the zebrafish lateral line.

    Science.gov (United States)

    Ou, Henry; Simon, Julian A; Rubel, Edwin W; Raible, David W

    2012-06-01

    The zebrafish lateral line is an efficient model system for the evaluation of chemicals that protect and damage hair cells. Located on the surface of the body, lateral line hair cells are accessible for manipulation and visualization. The zebrafish lateral line system allows rapid screens of large chemical libraries, as well as subsequent thorough evaluation of interesting compounds. In this review, we focus on the results of our previous screens and the evolving methodology of our screens for chemicals that protect hair cells, and chemicals that damage hair cells using the zebrafish lateral line. Copyright © 2012 Elsevier B.V. All rights reserved.

  14. Mianserin affects alarm reaction to conspecific chemical alarm cues in Nile tilapia.

    Science.gov (United States)

    Barreto, Rodrigo Egydio

    2017-02-01

    In this study, I show that mianserin, a chemical with serotonin and adrenoceptor antagonist activities, increases fish vulnerability to a potential predator threat, when prey fish must deal with this threat based on conspecific chemical alarm cues. For that, I evaluated whether mianserin, diluted in the water, influences the behavioral responses of Nile tilapia (Oreochromis niloticus) to conspecific skin extract (chemical alarm cues). I found that, while mianserin did not abolished antipredator responses, this drug mitigates some components of this defensive reaction. Thus, a potential decrease in serotonin and adrenergic activities reduces the ability of dealing with predators when perceiving conspecific chemical alarm cues.

  15. Variation of cuticular chemical compounds in three species of Mischocyttarus (Hymenoptera: Vespidae eusocial wasps

    Directory of Open Access Journals (Sweden)

    Eva Ramona Pereira Soares

    Full Text Available Abstract The social wasps have a remarkable system of organization in which chemical communication mediate different behavioral interactions. Among the compounds involved in this process, cuticular hydrocarbons are considered the main signals for nestmate recognition, caste differentiation, and fertility communication. The aims of this study were to describe the cuticular chemical compounds of the species Mischocyttarus consimilis, Mischocyttarus bertonii, and Mischocyttarus latior, and to test whether these chemical compounds could be used to evaluate differences and similarities between Mischocyttarus species, using gas chromatography coupled to mass spectrometry (GC-MS. Workers from these three species presented a variety of hydrocarbons ranging from C17 to C37, and among the compounds identified, the most representative were branched alkanes, linear alkanes and alkenes. The results revealed quantitative and qualitative differences among the hydrocarbon profiles, as confirmed by discriminant analysis. This study supports the hypothesis that cuticular chemical profiles can be used as parameters to identify interspecific and intercolony differences in Mischocyttarus, highlighting the importance of these compounds for differentiation of species and populations.

  16. Variation in the chemical composition of the essential oils of different ...

    African Journals Online (AJOL)

    Jane

    2010-08-20

    Aug 20, 2010 ... 2. Fine qualitative analysis by gas phase chromatography coupled with mass spectrometry (GC-MS) to confirm chemical structures. The quantitative step was carried out using a Hewlett-Packard. HP 5890 chromatograph fitted with a flame ionisation detector equipped with HP ChemStation data acquisition ...

  17. Influence of Variation in Physical and Chemical Properties of Southern Red Oak Lumber on Decay Resistance

    Science.gov (United States)

    E. Richard Toole; W. N. Darwin

    1970-01-01

    Although differences in decay resistance of the heartwood of various oak species have long been recognized, the effect of changes in physical and chemical wood properties on this decay resistance have not been well defined. Scheffer et al (5) studied the decay resistance of seven native oaks. They found that, within the species of the red oak group studied, there were...

  18. Soil structure, colloids, and chemical transport as affected by short-term reducing conditions: a laboratory study

    Science.gov (United States)

    Upland soils in the Midwestern US often undergo reducing conditions when soils are temporally flooded during the spring and remain water saturated for days or weeks. Short-term reducing conditions change the chemistry of the soil and may affect soil structure and solution chemical transport. The eff...

  19. Seasonal variation in affective and other clinical symptoms among high-risk families for bipolar disorders in an Arctic population.

    Science.gov (United States)

    Pirkola, Sami; Eriksen, Heidi A; Partonen, Timo; Kieseppä, Tuula; Veijola, Juha; Jääskeläinen, Erika; Mylläri-Figuerola, Eeva-Maija; Salo, Paula M; Paunio, Tiina

    2015-01-01

    In bipolar disorder (BD), seasonality of symptoms is common and disturbances in circadian rhythms have been reported. We identified high-penetrance families in a geographically restricted area in Northern Fennoscandia and studied the seasonal variation of clinical symptoms among BD subjects and their healthy relatives. We explored the clinical characteristics of subjects living in Northern Fennoscandia, with extreme annual variation in daylight. Among known indigenous high-risk families for BD, we compared the affected ones (N=16) with their healthy relatives (N=15), and also included 18 healthy non-related controls from the same geographical area. Seasonal fluctuation in clinical measures was followed up at the 4 most demarcated photoperiodic time points of the annual cycle: around the summer solstice and autumn equinox in 2013, the winter solstice in 2013/2014, and the spring equinox in 2014. In the baseline, lifetime manic symptoms [Mood Disorder Questionnaire (MDQ)] and morningness-eveningness questionnaire type (MEQ) were registered, whereas in the follow-up, depressive [Beck Depression Inventory (BDI)] and distress [General Health Questionnaire (GHQ-12)] symptoms and alcohol consumption and sleep were recorded. Possibly indicative or statistically significant differences in symptoms between the affected subjects and their healthy relatives were the BDI winter (13.3 vs. 2.6, t=-2.51, p=0.022) and spring scores (12.6 vs. 3.2, t=-1.97, p=0.063) and GHQ winter (4.2 vs. 0.82, t=-2.08, p=0.052) and spring scores (3.8 vs. 0.82, t=-1.97, p=0.063). Scores were higher among the affected subjects, exceeding a possibly diagnostic threshold (10 and 3) at all the time points, and without the notable seasonality which was observed among the healthy relatives. In the overall population, MDQ and MEQ scores had an inverse correlation (-0.384, significant at 0.016), indicating increased lifetime manic behaviour among "the night owl" chronotype subjects. In an Arctic population

  20. Seasonal variation in affective and other clinical symptoms among high-risk families for bipolar disorders in an Arctic population

    Directory of Open Access Journals (Sweden)

    Sami Pirkola

    2015-11-01

    Full Text Available Background: In bipolar disorder (BD, seasonality of symptoms is common and disturbances in circadian rhythms have been reported. Objectives: We identified high-penetrance families in a geographically restricted area in Northern Fennoscandia and studied the seasonal variation of clinical symptoms among BD subjects and their healthy relatives. Design: We explored the clinical characteristics of subjects living in Northern Fennoscandia, with extreme annual variation in daylight. Among known indigenous high-risk families for BD, we compared the affected ones (N=16 with their healthy relatives (N=15, and also included 18 healthy non-related controls from the same geographical area. Seasonal fluctuation in clinical measures was followed up at the 4 most demarcated photoperiodic time points of the annual cycle: around the summer solstice and autumn equinox in 2013, the winter solstice in 2013/2014, and the spring equinox in 2014. In the baseline, lifetime manic symptoms [Mood Disorder Questionnaire (MDQ] and morningness–eveningness questionnaire type (MEQ were registered, whereas in the follow-up, depressive [Beck Depression Inventory (BDI] and distress [General Health Questionnaire (GHQ-12] symptoms and alcohol consumption and sleep were recorded. Results: Possibly indicative or statistically significant differences in symptoms between the affected subjects and their healthy relatives were the BDI winter (13.3 vs. 2.6, t=−2.51, p=0.022 and spring scores (12.6 vs. 3.2, t=−1.97, p=0.063 and GHQ winter (4.2 vs. 0.82, t=−2.08, p=0.052 and spring scores (3.8 vs. 0.82, t=−1.97, p=0.063. Scores were higher among the affected subjects, exceeding a possibly diagnostic threshold (10 and 3 at all the time points, and without the notable seasonality which was observed among the healthy relatives. In the overall population, MDQ and MEQ scores had an inverse correlation (−0.384, significant at 0.016, indicating increased lifetime manic behaviour among

  1. Variation in Dube3a expression affects neurotransmission at the Drosophila neuromuscular junction

    Directory of Open Access Journals (Sweden)

    Colleen Valdez

    2015-07-01

    Full Text Available Changes in UBE3A expression levels in neurons can cause neurogenetic disorders ranging from Angelman syndrome (AS (decreased levels to autism (increased levels. Here we investigated the effects on neuronal function of varying UBE3A levels using the Drosophila neuromuscular junction as a model for both of these neurogenetic disorders. Stimulations that evoked excitatory junction potentials (EJPs at 1 Hz intermittently failed to evoke EJPs at 15 Hz in a significantly higher proportion of Dube3a over-expressors using the pan neuronal GAL4 driver C155-GAL4 (C155-GAL4>UAS-Dube3a relative to controls (C155>+ alone. However, in the Dube3a over-expressing larval neurons with no failures, there was no difference in EJP amplitude at the beginning of the train, or the rate of decrease in EJP amplitude over the course of the train compared to controls. In the absence of tetrodotoxin (TTX, spontaneous EJPs were observed in significantly more C155-GAL4>UAS-Dube3a larva compared to controls. In the presence of TTX, spontaneous and evoked EJPs were completely blocked and mEJP amplitude and frequency did not differ among genotypes. These data suggest that over-expression of wild type Dube3a, but not a ubiquitination defective Dube3a-C/A protein, compromises the ability of motor neuron axons to support closely spaced trains of action potentials, while at the same time increasing excitability. EJPs evoked at 15 Hz in the absence of Dube3a (Dube3a15b homozygous mutant larvae decayed more rapidly over the course of 30 stimulations compared to w1118 controls, and Dube3a15b larval muscles had significantly more negative resting membrane potentials (RMP. However, these results could not be recapitulated using RNAi knockdown of Dube3a in muscle or neurons alone, suggesting more global developmental defects contribute to this phenotype. These data suggest that reduced UBE3A expression levels may cause global changes that affect RMP and neurotransmitter release from

  2. Mixtures of environmentally relevant endocrine disrupting chemicals affect mammary gland development in female and male rats

    DEFF Research Database (Denmark)

    Mandrup, Karen Riiber; Johansson, Hanna Katarina Lilith; Boberg, Julie

    2015-01-01

    Estrogenic chemicals are able to alter mammary gland development in female rodents, but little is known on the effects of anti-androgens and mixtures of endocrine disrupting chemicals (EDCs) with dissimilar modes of action. Pregnant rat dams were exposed during gestation and lactation to mixtures...

  3. Chemical and isotopic variations of precipitation in the Los Alamos Region, New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Adams, A.I.; Goff, F.; Counce, D.

    1995-02-01

    Precipitation collectors were installed at 14 locations on the Pajarito Plateau and surrounding areas to study variations in chemistry, stable isotopes and tritium for the years 1990 to 1993. The volume of precipitation was measured and samples were collected and analyzed every three to four months. All precipitation samples contain <2.50 mg/kg Cl and have pH values ranging from 5.4 to 6.7. The stable isotope ({delta}D/{delta}{sup 18}O) results record seasonal variations in precipitation as the weather patterns shift from sources in the Pacific Ocean to sources in the Gulf of Mexico. The stable isotope results also show isotopic variations due to elevation differences among the collection points. The tritium contents ({sup 3}H) in rain samples vary from 6.54 T.U. to 141 T.U. Contouring of high tritium values (e.g. >20 T.U.) from each collection period clearly shows that Laboratory activities release some tritium to the atmosphere. The effect of these releases are well below the limits set by the Environmental Protection Agency for drinking water (about 6200 T.U.). The magnitude of the releases is apparently greatest during the summer months. However, anomalous tritium values are detected as far north as Espahola, New Mexico for many collection periods. Tritium releases by the Laboratory are not constant; thus, the actual amount of tritium in each release has been diluted in the composite samples of our three to four month collection periods.

  4. Quantifying how fine-grained environmental heterogeneity and genetic variation affect demography in an annual plant population.

    Science.gov (United States)

    Latimer, Andrew M; Jacobs, Brooke S

    2012-11-01

    The ability of plant species to colonize new habitats and persist in changing environments depends on their ability to respond plastically to environmental variation and on the presence of genetic variation, thus allowing adaptation to new conditions. For invasive species in particular, the relationship between phenotypic trait expression, demography, and the quantitative genetic variation that is available to respond to selection are likely to be important determinants of the successful establishment and persistence of populations. However, the magnitude and sources of individual demographic variation in exotic plant populations remain poorly understood. How important is plasticity versus adaptability in populations of invasive species? Among environmental factors, is temperature, soil nutrients, or competition most influential, and at what scales and life stages do they affect the plants? To investigate these questions we planted seeds of the exotic annual plant Erodium brachycarpum into typical pasture habitat in a spatially nested design. Seeds were drawn from 30 inbred lines to enable quantification of genetic effects. Despite a positive population growth rate, a few plants (0.1 %) produced >50 % of the seeds, suggesting a low effective population size. Emergence and early growth varied by genotype, but as in previous studies on native plants, environmental effects greatly exceeded genetic effects, and survival was unrelated to genotype. Environmental influences shifted from microscale soil compaction and litter depth at emergence through to larger-scale soil nutrient gradients during growth and to competition during later survival and seed production. Temperature had no effect. Most demographic rates were positively correlated, but emergence was negatively correlated with other rates.

  5. The role of ensemble-based statistics in variational assimilation of cloud-affected observations from infrared imagers

    Science.gov (United States)

    Hacker, Joshua; Vandenberghe, Francois; Jung, Byoung-Jo; Snyder, Chris

    2017-04-01

    Effective assimilation of cloud-affected radiance observations from space-borne imagers, with the aim of improving cloud analysis and forecasting, has proven to be difficult. Large observation biases, nonlinear observation operators, and non-Gaussian innovation statistics present many challenges. Ensemble-variational data assimilation (EnVar) systems offer the benefits of flow-dependent background error statistics from an ensemble, and the ability of variational minimization to handle nonlinearity. The specific benefits of ensemble statistics, relative to static background errors more commonly used in variational systems, have not been quantified for the problem of assimilating cloudy radiances. A simple experiment framework is constructed with a regional NWP model and operational variational data assimilation system, to provide the basis understanding the importance of ensemble statistics in cloudy radiance assimilation. Restricting the observations to those corresponding to clouds in the background forecast leads to innovations that are more Gaussian. The number of large innovations is reduced compared to the more general case of all observations, but not eliminated. The Huber norm is investigated to handle the fat tails of the distributions, and allow more observations to be assimilated without the need for strict background checks that eliminate them. Comparing assimilation using only ensemble background error statistics with assimilation using only static background error statistics elucidates the importance of the ensemble statistics. Although the cost functions in both experiments converge to similar values after sufficient outer-loop iterations, the resulting cloud water, ice, and snow content are greater in the ensemble-based analysis. The subsequent forecasts from the ensemble-based analysis also retain more condensed water species, indicating that the local environment is more supportive of clouds. In this presentation we provide details that explain the

  6. Dopamine D1 receptor gene variation modulates opioid dependence risk by affecting transition to addiction.

    Directory of Open Access Journals (Sweden)

    Feng Zhu

    Full Text Available Dopamine D1 receptor (DRD1 modulates opioid reinforcement, reward, and opioid-induced neuroadaptation. We propose that DRD1 polymorphism affects susceptibility to opioid dependence (OD, the efficiency of transition to OD, and opioid-induced pleasure response. We analyzed potential association between seven DRD1 polymorphisms with the following traits: duration of transition from the first use to dependence (DTFUD, subjective pleasure responses to opioid on first use and post-dependence use, and OD risk in 425 Chinese with OD and 514 healthy controls. DTFUD and level of pleasure responses were examined using a semi-structured interview. The DTFUD of opioid addicts ranged from 5 days to 11 years. Most addicts (64.0% reported non-comfortable response upon first opioid use, while after dependence, most addicts (53.0% felt strong opioid-induced pleasure. Survival analysis revealed a correlation of prolonged DTFUD with the minor allele-carrying genotypes of DRD1 rs4532 (hazard ratios (HR = 0.694; p = 0.001 and rs686 (HR = 0.681, p = 0.0003. Binary logistic regression indicated that rs10063995 GT genotype (vs. GG+TT, OR = 0.261 could predict decreased pleasure response to first-time use and the minor alleles of rs686 (OR = 0.535 and rs4532 (OR = 0.537 could predict decreased post-dependence pleasure. Moreover, rs686 minor allele was associated with a decreased risk for rapid transition from initial use to dependence (DTFUD≤30 days; OR = 0.603 or post-dependence euphoria (OR = 0.603 relative to major allele. In conclusion, DRD1 rs686 minor allele decreases the OD risk by prolonging the transition to dependence and attenuating opioid-induced pleasure in Chinese.

  7. Dopamine D1 receptor gene variation modulates opioid dependence risk by affecting transition to addiction.

    Science.gov (United States)

    Zhu, Feng; Yan, Chun-xia; Wen, Yi-chong; Wang, Jiayin; Bi, Jinbo; Zhao, Ya-ling; Wei, Lai; Gao, Cheng-ge; Jia, Wei; Li, Sheng-bin

    2013-01-01

    Dopamine D1 receptor (DRD1) modulates opioid reinforcement, reward, and opioid-induced neuroadaptation. We propose that DRD1 polymorphism affects susceptibility to opioid dependence (OD), the efficiency of transition to OD, and opioid-induced pleasure response. We analyzed potential association between seven DRD1 polymorphisms with the following traits: duration of transition from the first use to dependence (DTFUD), subjective pleasure responses to opioid on first use and post-dependence use, and OD risk in 425 Chinese with OD and 514 healthy controls. DTFUD and level of pleasure responses were examined using a semi-structured interview. The DTFUD of opioid addicts ranged from 5 days to 11 years. Most addicts (64.0%) reported non-comfortable response upon first opioid use, while after dependence, most addicts (53.0%) felt strong opioid-induced pleasure. Survival analysis revealed a correlation of prolonged DTFUD with the minor allele-carrying genotypes of DRD1 rs4532 (hazard ratios (HR) = 0.694; p = 0.001) and rs686 (HR = 0.681, p = 0.0003). Binary logistic regression indicated that rs10063995 GT genotype (vs. GG+TT, OR = 0.261) could predict decreased pleasure response to first-time use and the minor alleles of rs686 (OR = 0.535) and rs4532 (OR = 0.537) could predict decreased post-dependence pleasure. Moreover, rs686 minor allele was associated with a decreased risk for rapid transition from initial use to dependence (DTFUD≤30 days; OR = 0.603) or post-dependence euphoria (OR = 0.603) relative to major allele. In conclusion, DRD1 rs686 minor allele decreases the OD risk by prolonging the transition to dependence and attenuating opioid-induced pleasure in Chinese.

  8. Climate Change-Related Hydrologic Variation Affects Dissolved Organic Carbon Export to the Gulf of Maine

    Science.gov (United States)

    Huntington, T. G.; Balch, W. M.; Aiken, G.; Butler, K. D.; Billmire, M.; Roesler, C. S.; Camill, P.; Bourakovsky, A.

    2014-12-01

    Ongoing climate change is affecting the timing and amount of dissolved organic carbon (DOC) exported to the Gulf of Maine (GoM) through effects on hydrologic conditions. Climate warming in the northeast United States has resulted in decreases in snowfall amount and increases in the proportion of annual precipitation that falls as rain compared with snow. Warming has resulted in an increase in runoff during winter and earlier snowmelt and associated high spring flow. Increases in annual precipitation have resulted in increases in annual runoff. Increases in flashiness in some rivers have resulted in higher variability in daily runoff. DOC fluxes were estimated for water years 1950 through 2012 in eight rivers draining to the GoM that had long-term discharge data and data for DOC during all months of the year. These estimates used LOADEST to fit a seasonally-adjusted concentration - discharge relation. The adjusted maximum likelihood estimation (AMLE) method was used to estimate loads. One of several predefined regression models evaluated in LOADEST was selected based on the Akaike information criterion (AIC) for each river. This analysis assumed stationarity in the concentration - discharge relations. The proportion of total annual DOC exported during winter has increased. The proportion of DOC exported during March and April has also increased and the proportion exported during May has decreased in association with earlier snowmelt runoff and earlier recession to summer low flow. The total annual DOC exported by these rivers increased significantly from 1950 to 2012. The increase in flashiness has increased daily variability in DOC export in some rivers. Changes in the timing and amount of DOC exported to the near coastal ocean may influence marine biogeochemistry including the development of nuisance and harmful algal blooms, carbon sequestration, and the interpretation of satellite-derived ocean color. Terrestrially derived DOC exported to the marine environment

  9. Neutral genetic variation in adult Chinook salmon (Oncorhynchus tshawytscha) affects brain-to-body trade-off and brain laterality.

    Science.gov (United States)

    Wiper, Mallory L; Lehnert, Sarah J; Heath, Daniel D; Higgs, Dennis M

    2017-12-01

    Low levels of heterozygosity can have detrimental effects on life history and growth characteristics of organisms but more subtle effects such as those on trade-offs of expensive tissues and morphological laterality, especially of the brain, have not been explicitly tested. The objective of the current study was to investigate how estimated differences in heterozygosity may potentially affect brain-to-body trade-offs and to explore how these heterozygosity differences may affect differential brain growth, focusing on directional asymmetry in adult Chinook salmon ( Oncorhynchus tshawytscha ) using the laterality and absolute laterality indices. Level of inbreeding was estimated as mean microsatellite heterozygosity resulting in four 'inbreeding level groups' (Very High, High, Medium, Low). A higher inbreeding level corresponded with a decreased brain-to-body ratio, thus a decrease in investment in brain tissue, and also showed a decrease in the laterality index for the cerebellum, where the left hemisphere was larger than the right across all groups. These results begin to show the role that differences in heterozygosity may play in differential tissue investment and in morphological laterality, and may be useful in two ways. Firstly, the results may be valuable for restocking programmes that wish to emphasize brain or body growth when crossing adults to generate individuals for release, as we show that genetic variation does affect these trade-offs. Secondly, this study is one of the first examinations to test the hypothesized relationship between genetic variation and laterality, finding that in Chinook salmon there is potential for an effect of inbreeding on lateralized morphology, but not in the expected direction.

  10. Cu grown carbon nanofibers - Variation of their chemical and physical properties

    Science.gov (United States)

    Bhoware, Shrikant; Maubane, Manoko S.; Phaahlamohlaka, Tumelo; Shaikjee, Ahmed; Coville, Neil J.

    2013-07-01

    Carbon nanofibers (CNFs) were prepared by passing a mixture of acetylene/H2 or acetylene/N2 over different Cu catalysts. The Soxhlet extracted CNFs were characterized by TEM, TGA and IR spectroscopy and revealed that the morphology, diameter distribution and crystallinity of the CNFs varied with gas atmosphere and Cu particle size. TEM images revealed that coiled CNFs were only produced from Cu/SiO2 grown in the presence of H2. It is thus revealed that the CNFs produced by different Cu catalysts have different chemical and physical properties and that these properties correlate with catalyst particle size and the gas mixtures used.

  11. Type 2 diabetes mellitus interacts with obesity and common variations in PLTP to affect plasma phospholipid transfer protein activity.

    Science.gov (United States)

    Dullaart, R P F; Vergeer, M; de Vries, R; Kappelle, P J W H; Dallinga-Thie, G M

    2012-05-01

    Phospholipid transfer protein (PLTP) is an emerging cardiometabolic risk marker that is important in high-density lipoprotein (HDL) and triglyceride metabolism. Plasma PLTP activity is elevated in type 2 diabetes mellitus, whereas glucose may regulate PLTP gene transcription in vitro. Of interest, common PLTP variations that predict cardiovascular disease have been identified recently. We investigated whether the diabetic state is able to amplify relationships between obesity and PLTP gene variations with circulating PLTP levels. Plasma PLTP activity (using a phospholipid vesicles-HDL system), PLTP gene score [number of PLTP activity-decreasing alleles based on two tagging polymorphisms (rs378114 and rs60- 65904)] and waist circumference were determined in two Dutch cohorts comprising 237 patients with type 2 diabetes and 78 control subjects. Patients with diabetes were more obese (P diabetic and control subjects (P = 0.40). PLTP activity was highest in patients with diabetes with an enlarged waist and lowest in control subjects with a normal waist circumference (P Multiple linear regression analysis revealed a positive interaction between diabetes status and waist circumference on PLTP activity (β = 0.200, P = 0.005). Furthermore, diabetes status (β = -0.485, P = 0.046) or HbA1c (β = -0.240, P = 0.035) interacted with PLTP gene score to affect PLTP activity. Type 2 diabetes and enlarged waist circumference interact to impact on plasma PLTP activity. Diabetes may also amplify the association between plasma PLTP activity and common PLTP gene variations. Our findings support the hypothesis that diabetes-environment and diabetes-gene interactions govern plasma PLTP activity. © 2011 The Association for the Publication of the Journal of Internal Medicine.

  12. Chemical composition and seasonal variation of the volatile oils from leaves of Michelia champaca L., Magnoliaceae

    Directory of Open Access Journals (Sweden)

    João Henrique G. Lago

    Full Text Available The volatile oils from leaves of Michelia champaca L. collected bimonthly during one year (four times on the fifteenth day of January, March, May, July, September, and November - 2004 were subjected to GC/FID and GC-MS analysis, from which thirteen components were identified. Additionally, part of the oil obtained from January collection was subjected to fractionation over silica gel soaked with AgNO3 to afford five of the main sesquiterpenes (β-elemene, β-caryophyllene, α-humulene, β-selinene, and α-cadinol. The obtained data showed a significative variation in the proportions of the components, which could be associated to climatic parameters in each collection periods.

  13. Intraskeletal Chemical Variation Related to Diagenetic Processes: A Late Roman Necropolis Case

    OpenAIRE

    Gianni Gallello; Silvia Scopa; Julia Kuligowski; Fulvio Bartoli; Francesco Malegni; Agustín Pastor

    2015-01-01

    The aim of the present study was to define a methodological strategy for understanding how post- mortem degradation in bones caused by the environment affects different skeletal parts and for selecting better preserved bone samples employing rare earth elements (REEs) analysis and multivariate statistics. It is the first time that REEs are used to evaluate diagenesis impact in archaeological bones. To test our methodological proposal the samples selected belong to adult and young individuals ...

  14. How spatial variation in areal extent and configuration of labile vegetation states affect the riparian bird community in Arctic tundra.

    Directory of Open Access Journals (Sweden)

    John-André Henden

    Full Text Available The Arctic tundra is currently experiencing an unprecedented combination of climate change, change in grazing pressure by large herbivores and growing human activity. Thickets of tall shrubs represent a conspicuous vegetation state in northern and temperate ecosystems, where it serves important ecological functions, including habitat for wildlife. Thickets are however labile, as tall shrubs respond rapidly to both abiotic and biotic environmental drivers. Our aim was to assess how large-scale spatial variation in willow thicket areal extent, configuration and habitat structure affected bird abundance, occupancy rates and species richness so as to provide an empirical basis for predicting the outcome of environmental change for riparian tundra bird communities. Based on a 4-year count data series, obtained through a large-scale study design in low arctic tundra in northern Norway, statistical hierarchical community models were deployed to assess relations between habitat configuration and bird species occupancy and community richness. We found that species abundance, occupancy and richness were greatly affected by willow areal extent and configuration, habitat features likely to be affected by intense ungulate browsing as well as climate warming. In sum, total species richness was maximized in large and tall willow patches of small to intermediate degree of fragmentation. These community effects were mainly driven by responses in the occupancy rates of species depending on tall willows for foraging and breeding, while species favouring other vegetation states were not affected. In light of the predicted climate driven willow shrub encroachment in riparian tundra habitats, our study predicts that many bird species would increase in abundance, and that the bird community as a whole could become enriched. Conversely, in tundra regions where overabundance of large herbivores leads to decreased areal extent, reduced height and increased fragmentation

  15. Inhaled corticosteroid metered-dose inhalers: how do variations in technique for solutions versus suspensions affect drug distribution?

    Science.gov (United States)

    Robinson, Christie A; Tsourounis, Candy

    2013-03-01

    To assess the literature that evaluates how variations in metered-dose inhaler (MDI) technique affect lung distribution for inhaled corticosteroids (ICSs) formulated as MDI suspensions and solutions. PubMed (up to November 2012) and Cochrane Library (up to November 2012) were searched using the terms metered-dose inhalers, HFA 134a, Asthma/*drug therapy, and inhaled corticosteroids. In addition, reference citations from publications identified were reviewed. All articles in English from the data sources that assessed MDI technique comparing total lung distribution (TLD) of MDI solutions or suspensions formulated with ICSs were included in the review. Five relevant studies were identified. Five controlled studies compared how variations in MDI technique affect TLD for ICS MDI solutions with suspensions. MDI solutions resulted in greater TLD compared with larger particle MDI suspensions. Delayed or early inspiration upon device actuation of MDI solutions resulted in less TLD than coordinated actuation, but with a 3- to 4-times greater TLD than MDI suspensions inhaled using a standard technique. A sixth study evaluated inspiratory flow rates (IFR) for small, medium, and large particles. Rapid and slow IFRs resulted in similar TLD for small particles, while far fewer particles reached the airways with medium and large particles at rapid, rather than slow, IFRs. Based on the literature evaluated, standard MDI technique should be used for ICS suspensions. ICS MDI solutions can provide a higher average TLD than larger-particle ICS suspensions using standard technique, discoordinated inspiration and medication actuation timing, or rapid and slow IFRs. ICS MDI solutions allow for a more forgiving technique, which makes them uniquely suitable options for patients with asthma who have difficultly with MDI technique.

  16. Chemical and biological attributes of a lowland soil affected by land leveling

    Directory of Open Access Journals (Sweden)

    José Maria Barbat Parfitt

    2013-11-01

    Full Text Available The objective of this work was to evaluate the relationship between soil chemical and biological attributes and the magnitude of cuts and fills after the land leveling process of a lowland soil. Soil samples were collected from the 0 - 0.20 m layer, before and after leveling, on a 100 point grid established in the experimental area, to evaluate chemical attributes and soil microbial biomass carbon (MBC. Leveling operations altered the magnitude of soil chemical and biological attributes. Values of Ca, Mg, S, cation exchange capacity, Mn, P, Zn, and soil organic matter (SOM decreased in the soil profile, whereas Al, K, and MBC increased after leveling. Land leveling decreased in 20% SOM average content in the 0 - 0.20 m layer. The great majority of the chemical attributes did not show relations between their values and the magnitude of cuts and fills. The relation was quadratic for SOM, P, and total N, and was linear for K, showing a positive slope and indicating increase in the magnitude of these attributes in cut areas and stability in fill areas. The relationships between these chemical attributes and the magnitude of cuts and fills indicate that the land leveling map may be a useful tool for degraded soil recuperation through amendments and organic fertilizers.

  17. Variation in chemical composition and physical characteristics of cereal grains from different genotypes

    DEFF Research Database (Denmark)

    Rodehutscord, Markus; Rückert, Christine; Maurer, Hans Peter

    2016-01-01

    Genotypes of cereal grains, including winter barley (n = 21), maize (n = 27), oats (n = 14), winter rye (n = 22), winter triticale (n = 21) and winter wheat (n = 29), were assayed for their chemical composition and physical characteristics as part of the collaborative research project referred....... The mean lysine concentration of protein was the highest in oats (4.2 g/16 g N) and the lowest in wheat (2.7 g/16 g N). Significant differences were also detected in the concentrations of macro elements as well as iron, manganese, zinc and copper. Concentrations of arsenic, cadmium and lead were below......, barley and maize, and it was not detectable in oats. Substantial differences were seen in the thousand seed weight, test weight, falling number and extract viscoelasticity characteristics. The study is a comprehensive overview of the composition of different cereal grain genotypes when grown on the same...

  18. Variational Energy Decomposition Analysis of Chemical Bonding. 1. Spin-Pure Analysis of Single Bonds.

    Science.gov (United States)

    Levine, Daniel S; Horn, Paul R; Mao, Yuezhi; Head-Gordon, Martin

    2016-10-11

    We have designed an energy decomposition analysis (EDA) to gain a deeper understanding of single chemical bonds, that is, those in which the interacting fragments are doublet open-shell systems but the supersystem is closed-shell. The method is a spin-pure extension of the absolutely localized molecular orbital (ALMO) EDA to the one-pair perfect pairing energy (equivalently to an active space of two electrons in two orbitals). The total interaction energy is broken up into four terms: frozen interactions, spin-coupling, polarization, and charge-transfer. A variety of single bonds are analyzed and, in addition, we use this method to show how solvation changes the nature of bonds, producing different results in the gas-phase and with explicit solvent molecules.

  19. Physico-Chemical Properties of Three Salt-Affected Soils in the ...

    African Journals Online (AJOL)

    komla

    The climate in the study area is semi-arid tropical with average daily temperatures ranging 27–28 °C with no pronounced variation during the ..... Yellowish brown and olive brown mottles, common, ..... Soils can change when there is rapid change in their environment, which also influences their surface chemistry (Schofield ...

  20. Chemical UV filters can affect human sperm function in a progesterone-like manner

    DEFF Research Database (Denmark)

    Rehfeld, Anders; Egeberg, Dorte; Almstrup, Kristian

    2018-01-01

    Human sperm cell function must be precisely regulated to achieve natural fertilization. Progesterone released by the cumulus cells surrounding the egg induces a Ca2+-influx into human sperm cells via the CatSper Ca2+-channel and thereby controls sperm function. Multiple chemical UV filters have...... the effect of progesterone on Ca2+-signaling in human sperm cells, can similarly mimic the effect of progesterone on acrosome reaction and sperm penetration. Human exposure to these chemical UV filters may impair fertility by interfering with sperm function, e.g. through induction of premature acrosome...

  1. Structural and chemical variations in phlogopite from lamproitic rocks of the Central Mediterranean region

    Science.gov (United States)

    Lepore, Giovanni O.; Bindi, Luca; Pedrazzi, Giuseppe; Conticelli, Sandro; Bonazzi, Paola

    2017-08-01

    Micas from mafic ultrapotassic rocks with lamproitic affinity from several localities of the Central Mediterranean region were studied through single-crystal X-ray diffraction (SC-XRD), electron microprobe analysis (EMPA) and Secondary Ion Mass Spectrometry (SIMS); Mössbauer Spectroscopy (MöS), when feasible, was also applied to minimise the number of unknown variables and uncertainties. Analysed lamproitic samples cover the most important Central Mediterranean type localities, from Plan d'Albard (Western Alps) to Sisco (Corsica), Montecatini Val di Cecina and Orciatico (Tuscany, Italy) and Torre Alfina (Northern Latium, Italy). The studied crystals show distinctive chemical and structural features; all of them belong to the phlogopite-annite join and crystallise in the 1M polytype, except for micas from Torre Alfina, where both 1M and 2M1 polytypes were found. Studied micas have variable but generally high F and Ti contents, with Mg/(Mg + Fe) ranging from 0.5 to 0.9; 2M1 crystals from Torre Alfina radically differ in chemical composition, showing high contents of Ti and Fe as well as of Al in both tetrahedra and octahedra, leading to distinctive structural distortions, especially in tetrahedral sites. SIMS data indicate that studied micas are generally dehydrogenated with OH contents ranging from 0.2 apfu (atoms per formula unit) for Orciatico and Torre Alfina to 1.4 for Plan d'Albard crystals; this feature is also testified by the length of the c parameter, which decreases with the loss of hydrogen and/or the increase of the F → OH substitution. Chemical and structural data suggest that the entry of high charge octahedral cations is mainly balanced by an oxy mechanism and, to a lesser extent, by a M3 +,4 +-Tschermak substitution. Our data confirm that Ti preferentially partitions into the M2 site and that different Ti and F contents, as well as different K/Al values, are both dependant upon fH2O and the composition of magma rather than controlled by P and T

  2. Ultrasonic waveform upshot on mass variation within single cavitation bubble: Investigation of physical and chemical transformations.

    Science.gov (United States)

    Kerboua, Kaouther; Hamdaoui, Oualid

    2018-04-01

    The mechanical disturbance created by an ultrasonic wave travelling through a liquid medium induces the formation of cavitation that oscillates due to rarefaction and compression of the wave. The duration and the magnitude of the pressure applied by the ultrasonic wave at each instant would generate a specific impact on the variation of the bubble radius, the temperature, the pressure and the mass inside it. In this paper, a numerical study is conducted to simulate four waveforms (sinusoidal, square, triangular and sawtooth) travelling an aqueous media saturated with oxygen with an amplitude of 1.5 and 2 atm and a frequency of 200, 300 and 500 kHz. The purpose is to highlight the mass evolution within acoustic cavitation bubble during one cycle due to physical transformations and sonochemical effect. The obtained results demonstrated that square signal enhances temperature and pressure growth inside the bubble, as well as mass transfer by evaporation and condensation. This leads to an improvement of produced quantities of free radicals but also to a selectivity of O as a major product in the detriment of HO 2 and OH. These trends are less and less observed when passing to sinusoidal, triangular and square signal. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Variation in physico-chemical/analytical characteristics of oil among different flaxseed (Linum usittatissimum L. cultivars

    Directory of Open Access Journals (Sweden)

    NAZIA YAQOOB

    2016-03-01

    Full Text Available The present study evaluates and compares the proximate parameters of flaxseed, as well as the physicochemical characteristics of the extracted flaxseed oils of locally grown eight cultivars. The oil, protein, fiber and ash content of the seeds ranged from32.56-39.98%, 16.02-18.50%, 23.30-26.88 and 3.20-3.60%, respectively showing considerable variation among cultivars. The quality attributes such as unsaponifiable matter, peroxide value, acid value, para-anisidine value, conjugateddienes and trienes as well as tocopherols content of the tested flaxseed oils varied significantly (p<0.05 among cultivars. The major tocopherol was γ-tocopherol (173.7 to 257.9 mg/Lfollowed by relatively low quantities of α-tocopherol (8-12 mg/L, while δ-tocopherol was not detected.α-Linolenic acid was found to be the principal fatty acid in the range of 44.51 to 54.87%, while the second major fatty acid present in the oils was oleic acid (21.05 to 30.96%. The variationin the characteristics of oils among different cultivars observed during present investigation might be attributed to difference in genetic makeup and harvesting regimes of the flax plants.

  4. Variation of atmospheric tritium concentration in three chemical forms at Toki, Japan: 2004-12.

    Science.gov (United States)

    Tanaka, M; Uda, T

    2015-11-01

    Atmospheric tritium concentrations of HTO, HT and CH3T have been measured at Toki, Japan, for the environmental impact assessment of tritium for a fusion test facility. According to the data from 2004 to 2012, the concentrations of HT and HTO in water vapour tend to increase in spring. The seasonal variation in HT concentration at Toki was compared with the H2 concentration between 1990 and 2005 at Tae-ahn Peninsula, Republic of Korea, which is at approximately the same latitude as Toki. The monthly average of HT-specific activity varied from 1.24 × 10(5) to 1.76 × 10(5) TU. The peak of the monthly average H2 concentration did not match that of HT. This indicates that the mechanism of the production or the source of HT might be different from the production mechanism of H2. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  5. Simulation for spatio-temporal variation of chemically active species in an atmospheric pressure streamer discharge.

    Science.gov (United States)

    Komuro, Atsushi; Takaahshi, Kazunori; Ando, Akira

    2016-09-01

    Spatiotemporal variation of radical density in an atmospheric pressure plasma discharge has been investigated by two-dimensional numerical simulation. Behaviors of radicals are characterized by four areas as ``Hot anode region'', ``Secondary streamer region'', ``Primary streamer region'', and ``Near-cathode region''. Although the reduced electric field in ``Hot anode region'' is relatively high, the gas temperature also increases and the ozone destruction process proceed. On the other hand, in ``Near-cathode region'', the high-energy radicals such as N(4S) is effectively produced because the instantaneous value of reduced electric field is high. Behaiviour of OH is also investigated. The results show that OH is effectively produced in ``Secondary streamer region'' and is not effective in ``Hot anode region''. This is because the reduced electric filed in ``Secondary streamer region'' is sufficiently high for the dissociation of H2O by O(D) and N2(a) and the gas temperature in ``Hot anode region'' is too high for the production of OH.

  6. Effects of chemical composition variation on the dynamics of ruminal fermentation and biological value of corn milling (co)products.

    Science.gov (United States)

    Tedeschi, L O; Kononoff, P J; Karges, K; Gibson, M L

    2009-01-01

    The objectives of this study were to evaluate the dynamics of gas production of several corn (co)products, to develop equations to predict the rate of ruminal fiber digestion, to estimate total digestible nutrients (TDN) and net energy for lactation (NE(L)), and to assess the stochasticity of chemical composition and nutritive value variability. Four corn milling (co)products were evaluated in this study: high protein dried distillers grains (HP-DDG), corn bran (BRAN) and dehydrated germ (GERM), and a dried distillers grains plus soluble produced with a low-heat drying process (BPX). Alfalfa hay was used as an internal standard feed in the in vitro fermentation dynamics analysis. Standard chemical analyses, in vitro digestibility, and in vitro gas production techniques were used to obtain the necessary physicochemical characterization of feeds. The in vitro dry matter digestibility at 24 and 48 h of incubation decreased exponentially as acid detergent insoluble nitrogen increased. However, the degree of in vitro dry matter digestibility reduction was more accentuated at 24 than at 48 h of incubation. The difference among these feeds regarding the dynamics of the anaerobic fermentation within different substrates (intact feed, and fiber and defatted residues) was evaluated. Results suggested that the proportion of fiber digested in the rumen was affected by the degree of sample processing and fat removal. Fractional fermentation rate (kf) of neutral detergent residue (without sodium sulfite) and defatted fiber residue for BRAN, GERM, HP-DDG, and BPX was estimated to be 0.0635 and 0.0852 h(-1), 0.0803 and 0.0914 h(-1), 0.118 and 0.117 h(-1), and 0.0695 and 0.0844 h(-1), respectively. The most influential variables affecting kf(NDR) of HP-DDG and BPX also affected the predicted TDN, suggesting that fiber quality is essential to ensure higher TDN values for these feeds. Our study indicated that it is possible to routinely quantify the rate of fiber digestion and this

  7. Genetic adaptation of the human circadian clock to day-length latitudinal variations and relevance for affective disorders.

    Science.gov (United States)

    Forni, Diego; Pozzoli, Uberto; Cagliani, Rachele; Tresoldi, Claudia; Menozzi, Giorgia; Riva, Stefania; Guerini, Franca R; Comi, Giacomo P; Bolognesi, Elisabetta; Bresolin, Nereo; Clerici, Mario; Sironi, Manuela

    2014-01-01

    The temporal coordination of biological processes into daily cycles is a common feature of most living organisms. In humans, disruption of circadian rhythms is commonly observed in psychiatric diseases,including schizophrenia, bipolar disorder, depression and autism. Light therapy is the most effective treatment for seasonal affective disorder and circadian-related treatments sustain antidepressant response in bipolar disorder patients. Day/night cycles represent a major circadian synchronizing signal and vary widely with latitude. We apply a geographically explicit model to show that out-of-Africa migration, which led humans to occupy a wide latitudinal area, affected the evolutionary history of circadian regulatory genes. The SNPs we identify using this model display consistent signals of natural selection using tests based on population genetic differentiation and haplotype homozygosity. Signals of natural selection driven by annual photoperiod variation are detected for schizophrenia, bipolar disorder, and restless leg syndrome risk variants, in line with the circadian component of these conditions. Our results suggest that human populations adapted to life at different latitudes by tuning their circadian clock systems. This process also involves risk variants for neuropsychiatric conditions, suggesting possible genetic modulators for chronotherapies and candidates for interaction analysis with photoperiod-related environmental variables, such as season of birth, country of residence, shift-work or lifestyle habits.

  8. Ephemeral collision complexes mediate chemically termolecular transformations that affect system chemistry

    Science.gov (United States)

    Burke, Michael P.; Klippenstein, Stephen J.

    2017-11-01

    Termolecular association reactions involve ephemeral collision complexes—formed from the collision of two molecules—that collide with a third and chemically inert 'bath gas' molecule that simply transfers energy to/from the complex. These collision complexes are generally not thought to react chemically on collision with a third molecule in the gas-phase systems of combustion and planetary atmospheres. Such 'chemically termolecular' reactions, in which all three molecules are involved in bond making and/or breaking, were hypothesized long ago in studies establishing radical chain branching mechanisms, but were later concluded to be unimportant. Here, with data from ab initio master equation and kinetic-transport simulations, we reveal that reactions of H + O2 collision complexes with other radicals constitute major kinetic pathways under common combustion situations. These reactions are also found to influence flame propagation speeds, a common measure of global reactivity. Analogous chemically termolecular reactions mediated by ephemeral collision complexes are probably of significance in various combustion and planetary environments.

  9. Control of nanoparticle agglomeration through variation of the time-temperature profile in chemical vapor synthesis

    Science.gov (United States)

    Djenadic, Ruzica; Winterer, Markus

    2017-02-01

    The influence of the time-temperature history on the characteristics of nanoparticles such as size, degree of agglomeration, or crystallinity is investigated for chemical vapor synthesis (CVS). A simple reaction-coagulation-sintering model is used to describe the CVS process, and the results of the model are compared to experimental data. Nanocrystalline titania is used as model material. Titania nanoparticles are generated from titanium-tetraisopropoxide (TTIP) in a hot-wall reactor. Pure anatase particles and mixtures of anatase, rutile (up to 11 vol.%), and brookite (up to 29 vol.%) with primary particle sizes from 1.7 nm to 10.5 nm and agglomerate particle sizes from 24.3 nm to 55.6 nm are formed depending on the particle time-temperature history. An inductively heated furnace with variable inductor geometry is used as a novel system to control the time-temperature profile in the reactor externally covering a large wall temperature range from 873 K to 2023 K. An appropriate choice of inductor geometry, i.e. time-temperature profile, can significantly reduce the degree of agglomeration. Other particle characteristics such as crystallinity are also substantially influenced by the time-temperature profile.

  10. Control of nanoparticle agglomeration through variation of the time-temperature profile in chemical vapor synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Djenadic, Ruzica; Winterer, Markus, E-mail: markus.winterer@uni-due.de [Universität Duisburg-Essen, Nanoparticle Process Technology, Faculty of Engineering and CENIDE (Germany)

    2017-02-15

    The influence of the time-temperature history on the characteristics of nanoparticles such as size, degree of agglomeration, or crystallinity is investigated for chemical vapor synthesis (CVS). A simple reaction-coagulation-sintering model is used to describe the CVS process, and the results of the model are compared to experimental data. Nanocrystalline titania is used as model material. Titania nanoparticles are generated from titanium-tetraisopropoxide (TTIP) in a hot-wall reactor. Pure anatase particles and mixtures of anatase, rutile (up to 11 vol.%), and brookite (up to 29 vol.%) with primary particle sizes from 1.7 nm to 10.5 nm and agglomerate particle sizes from 24.3 nm to 55.6 nm are formed depending on the particle time-temperature history. An inductively heated furnace with variable inductor geometry is used as a novel system to control the time-temperature profile in the reactor externally covering a large wall temperature range from 873 K to 2023 K. An appropriate choice of inductor geometry, i.e. time-temperature profile, can significantly reduce the degree of agglomeration. Other particle characteristics such as crystallinity are also substantially influenced by the time-temperature profile.

  11. Alkaline peroxide pulping of oil palm empty fruit bunch by variation of chemical strength

    Science.gov (United States)

    Dermawan, Yunita Megasari; Ghazali, Arniza; Daud, Wan Rosli Wan; Lazin, Mohd Azli Khairil Mat

    2012-09-01

    Papers produced from oil palm empty fruit bunches (EFB) via Alkaline Peroxide Pulping (APP) was preceded by three main steps; dewaxing of EFB, alkaline peroxide (AP) impregnation into EFB and refining of biomass to generate pulp. The experiment was carried by varying chemical level and number of impregnation stages. For 2:2.5% AP level, two-stage impregnation improved hand sheets tear index by 45%, 164% boost in tensile index, 26% enhancement in zero span index and more than 5% in burst index. By applying 8:10% AP level, significant improvements were gained at the third and fourth stages of AP impregnation. Although there was no significant change in hand sheet strength with multiple impregnation for 4:5% AP level, improvement in brightness of hand sheets was apparent, analogous to the effect of increasing AP level. The found paper properties development show that alkaline peroxide pulping of EFB could be adapted to various targeted properties by adjustment of AP level and impregnation stages.

  12. Seasonal and diurnal hydro-chemical variations in a recreated reed bed

    Science.gov (United States)

    Stratford, C. J.; McCartney, M. P.; Williams, R. J.

    To help stem this decline, wetland areas are now being preserved and where possible created. This study investigated water quality in a recreated reed bed in south-west England designed specifically to provide habitat for birds. Since June 2000, continuous measurements of temperature, pH, electrical conductivity and dissolved oxygen have been logged. These data enable the partial pressure of CO2 to be calculated. This paper looks at the data collected up to November 2001. Despite similar solar radiation and water temperature conditions in both 2000 and 2001, peak summertime values of dissolved oxygen dropped from >100% to pH values dropped from >7.7 to water, may result from surface plant growth or from a reduction in submerged plant cover. The implications of these changing hydro-chemical conditions are that the site will be less able to support such a wide diversity of aquatic fauna, which will reduce the effectiveness of the site as a habitat for some bird species.

  13. Soil chemical properties affect the reaction of forest soil bacteria to drought and rewetting stress.

    Science.gov (United States)

    Chodak, Marcin; Gołębiewski, Marcin; Morawska-Płoskonka, Justyna; Kuduk, Katarzyna; Niklińska, Maria

    Reaction of soil bacteria to drought and rewetting stress may depend on soil chemical properties. The objectives of this study were to test the reaction of different bacterial phyla to drought and rewetting stress and to assess the influence of different soil chemical properties on the reaction of soil bacteria to this kind of stress. The soil samples were taken at ten forest sites and measured for pH and the contents of organic C (Corg) and total N (Nt), Zn, Cu, and Pb. The samples were kept without water addition at 20 - 30 °C for 8 weeks and subsequently rewetted to achieve moisture equal to 50 - 60 % of their maximum water-holding capacity. Prior to the drought period and 24 h after the rewetting, the structure of soil bacterial communities was determined using pyrosequencing of 16S rRNA genes. The drought and rewetting stress altered bacterial community structure. Gram-positive bacterial phyla, Actinobacteria and Firmicutes, increased in relative proportion after the stress, whereas the Gram-negative bacteria in most cases decreased. The largest decrease in relative abundance was for Gammaproteobacteria and Bacteroidetes. For several phyla the reaction to drought and rewetting stress depended on the chemical properties of soils. Soil pH was the most important soil property influencing the reaction of a number of soil bacterial groups (including all classes of Proteobacteria, Bacteroidetes, Acidobacteria, and others) to drought and rewetting stress. For several bacterial phyla the reaction to the stress depended also on the contents of Nt and Corg in soil. The effect of heavy metal pollution was also noticeable, although weaker compared to other chemical soil properties. We conclude that soil chemical properties should be considered when assessing the effect of stressing factors on soil bacterial communities.

  14. DPP4 gene variation affects GLP-1 secretion, insulin secretion, and glucose tolerance in humans with high body adiposity.

    Directory of Open Access Journals (Sweden)

    Anja Böhm

    Full Text Available Dipeptidyl-peptidase 4 (DPP-4 cleaves and inactivates the insulinotropic hormones glucagon-like peptide 1 (GLP-1 and gastric inhibitory polypeptide, collectively termed incretins. DPP-4 inhibitors entered clinical practice as approved therapeutics for type-2 diabetes in 2006. However, inter-individual variance in the responsiveness to DPP-4 inhibitors was reported. Thus, we asked whether genetic variation in the DPP4 gene affects incretin levels, insulin secretion, and glucose tolerance in participants of the TÜbingen Family study for type-2 diabetes (TÜF.Fourteen common (minor allele frequencies ≥0.05 DPP4 tagging single nucleotide polymorphisms (SNPs were genotyped in 1,976 non-diabetic TÜF participants characterized by oral glucose tolerance tests and bioimpedance measurements. In a subgroup of 168 subjects, plasma incretin levels were determined.We identified a variant, i.e., SNP rs6741949, in intron 2 of the DPP4 gene that, after correction for multiple comparisons and appropriate adjustment, revealed a significant genotype-body fat interaction effect on glucose-stimulated plasma GLP-1 levels (p = 0.0021. Notably, no genotype-BMI interaction effects were detected (p = 0.8. After stratification for body fat content, the SNP negatively affected glucose-stimulated GLP-1 levels (p = 0.0229, insulin secretion (p = 0.0061, and glucose tolerance (p = 0.0208 in subjects with high body fat content only.A common variant, i.e., SNP rs6741949, in the DPP4 gene interacts with body adiposity and negatively affects glucose-stimulated GLP-1 levels, insulin secretion, and glucose tolerance. Whether this SNP underlies the reported inter-individual variance in responsiveness to DPP-4 inhibitors, at least in subjects with high body fat content, remains to be shown.

  15. The Increasing Prevalence in Intersex Variation from Toxicological Dysregulation in Fetal Reproductive Tissue Differentiation and Development by Endocrine-Disrupting Chemicals

    Science.gov (United States)

    Rich, Alisa L.; Phipps, Laura M.; Tiwari, Sweta; Rudraraju, Hemanth; Dokpesi, Philip O.

    2016-01-01

    An increasing number of children are born with intersex variation (IV; ambiguous genitalia/hermaphrodite, pseudohermaphroditism, etc.). Evidence shows that endocrine-disrupting chemicals (EDCs) in the environment can cause reproductive variation through dysregulation of normal reproductive tissue differentiation, growth, and maturation if the fetus is exposed to EDCs during critical developmental times in utero. Animal studies support fish and reptile embryos exhibited IV and sex reversal when exposed to EDCs. Occupational studies verified higher prevalence of offspring with IV in chemically exposed workers (male and female). Chemicals associated with endocrine-disrupting ability in humans include organochlorine pesticides, poly-chlorinated biphenyls, bisphenol A, phthalates, dioxins, and furans. Intersex individuals may have concurrent physical disorders requiring lifelong medical intervention and experience gender dysphoria. An urgent need exists to determine which chemicals possess the greatest risk for IV and the mechanisms by which these chemicals are capable of interfering with normal physiological development in children. PMID:27660460

  16. The Increasing Prevalence in Intersex Variation from Toxicological Dysregulation in Fetal Reproductive Tissue Differentiation and Development by Endocrine-Disrupting Chemicals.

    Science.gov (United States)

    Rich, Alisa L; Phipps, Laura M; Tiwari, Sweta; Rudraraju, Hemanth; Dokpesi, Philip O

    2016-01-01

    An increasing number of children are born with intersex variation (IV; ambiguous genitalia/hermaphrodite, pseudohermaphroditism, etc.). Evidence shows that endocrine-disrupting chemicals (EDCs) in the environment can cause reproductive variation through dysregulation of normal reproductive tissue differentiation, growth, and maturation if the fetus is exposed to EDCs during critical developmental times in utero. Animal studies support fish and reptile embryos exhibited IV and sex reversal when exposed to EDCs. Occupational studies verified higher prevalence of offspring with IV in chemically exposed workers (male and female). Chemicals associated with endocrine-disrupting ability in humans include organochlorine pesticides, poly-chlorinated biphenyls, bisphenol A, phthalates, dioxins, and furans. Intersex individuals may have concurrent physical disorders requiring lifelong medical intervention and experience gender dysphoria. An urgent need exists to determine which chemicals possess the greatest risk for IV and the mechanisms by which these chemicals are capable of interfering with normal physiological development in children.

  17. Fine particles at a background site in Central France: Chemical compositions, seasonal variations and pollution events.

    Science.gov (United States)

    He, Lin; Chen, Hui; Rangognio, Jérôme; Yahyaoui, Abderrazak; Colin, Patrice; Wang, Jinhe; Daële, Véronique; Mellouki, Abdelwahid

    2018-01-15

    To expand our knowledge of regional fine particles in Central France (Centre-Val de Loire region), a field observation study of PM 2.5 was carried out at Verneuil site (46.81467N, 2.61012E, 180m.a.s.l.) from 2011 to 2014. The mass concentrations of water-soluble inorganic ions (WSIIs), organic carbon (OC), elemental carbon (EC) and biomass burning tracer (Levoglucosan) in PM 2.5 were measured. Annual average PM 2.5 mass concentrations were 11.8, 9.5, 12.6 and 10.2μg·m -3 in 2011, 2012, 2013 and 2014, respectively, three of four higher than the WHO guideline of 10μg·m -3 . Secondary inorganic aerosol (SIA) and organic matter (OM) appeared to be the major components in PM 2.5 in Verneuil, contributing 30.1-41.8% and 36.9-46.3%, respectively. Main chemical species were observed in the following order: winter≥spring>autumn>summer. Backward atmospheric trajectories were performed using Hysplit model and suggested that the PM 2.5 pollutants caused by atmospheric transport were mainly originated from European inland, mainly east to north-east areas. During the observation period, five pollution events were reported and indicated that not only the polluted air masses from central Europe but also the biomass burning from East Europe significantly influenced the air quality in Verneuil site. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Chemical profile and seasonal variation of phenolic acid content in bastard balm (Melittis melissophyllum L., Lamiaceae).

    Science.gov (United States)

    Skrzypczak-Pietraszek, Ewa; Pietraszek, Jacek

    2012-07-01

    Melittis melissophyllum L. is an old medicinal plant. Nowadays it is only used in the folk medicine but formerly it has been applied in the official medicine as a natural product described in French Pharmacopoeia. M. melissophyllum herbs used in our studies were collected from two localities in Poland in May and September. Methanolic plant extracts were purified by means of solid-phase extraction and then analysed by HPLC-DAD for their phenolic acid profile. Eleven compounds were identified in all plant samples and quantitatively analysed as: protocatechuic, chlorogenic, p-hydroxybenzoic, vanillic, caffeic, syringic, p-coumaric, ferulic, sinapic, o-coumaric and cinnamic acid. Plant materials contained free and bound phenolic acids. The main compounds were: p-hydroxybenzoic acid (30.21-54.16 mg/100 g dw and 37.04-56.75 mg/100 g dw, free and bound, respectively) and p-coumaric acid (40.48-80.55 mg/100 g dw and 28.09-40.85 mg/100 g dw, free and bound, respectively). The highest amounts of the investigated compounds were found in all samples collected in September, e.g. p-hydroxybenzoic acid (September 51.72-54.16 mg/100 g dw vs. May 30.21-34.07 mg/100 g dw), p-coumaric acid (September 77.14-80.55 mg/100 g dw vs. May 40.48-43.2 5mg/100 g dw). Multivariate statistical and data mining techniques, such as cluster analysis (CA) and principal component analysis (PCA), were used to characterize the sample populations according to the geographical localities, vegetation period and compound form (free or bound). To the best of our knowledge we report for the first time the results of quantitative analysis of M. melissophyllum phenolic acids and seasonal variation of their content. Plant herbs are usually collected at flowering for plant derived medical preparations. Our results show that it is not always the optimal time for the highest contents of active compounds. Copyright © 2012 Elsevier B.V. All rights reserved.

  19. Does environment affect the chemical evolution of star-forming galaxies?

    Science.gov (United States)

    Gupta, Anshu; Yuan, Tiantian; Kewley, Lisa; Tran, Kim-Vy; Martizzi, Davide; Torrey, Paul; Vogelsberger, Mark; Anshu Gupta

    2018-01-01

    Understanding the relative significance of gravitational and hydrodynamic interactions on the chemical evolution of cluster galaxies is fascinating and challenging. In this talk, I will present my observation of a cluster-scale gradient in the metallicity of star-forming galaxies as a complementary method to discern the impact of environment on chemical evolution. Our observations for MACS J1115+0129 show that cluster galaxies near the cluster center are more metal-rich compared to galaxies in the cluster outskirts. Using a semi-analytic model of ram pressure stripping, we prove that removal of low-metallicity gas is not sufficient to reproduce the metallicity gradient. I will also present our recent results from IllustrisTNG simulations predicting the "pre-enrichment" of progenitor cluster galaxies. Using tracer particles from IllustrisTNG simulations, we prove that inflow of enriched gas is the prime driver of the higher metal fraction in cluster galaxies compared to field galaxies.

  20. Technological, chemical, sensory, and microbiological examination of frozen chicken as affected by microwave thawing

    OpenAIRE

    Kenawi M.A.

    2005-01-01

    The effect of microwave heating as a thawing method on physical, chemical sensory, and microbiological properties of frozen chicken was investigated in comparison with other thawing methods (at ambient temperature, in refrigerator, and in running tap water). Microwave thawed chicken had the highest taste panel scores and the lowest drip percentage loss compared with the other thawing methods. Thiobarbituric acid value (TBA) remarkably increased the samples thawed at ambient temperature or und...

  1. Interactions Between Industrial Yeasts and Chemical Contaminants in Grape Juice Affect Wine Composition Profile

    Directory of Open Access Journals (Sweden)

    Etjen Bizaj

    2014-01-01

    Full Text Available The interaction between four industrial wine yeast strains and grape juice chemical contaminants during alcoholic fermentation was studied. Industrial strains of Saccharomyces cerevisiae (AWRI 0838, S. cerevisiae mutant with low H2S production phenotype (AWRI 1640, interspecies hybrid of S. cerevisiae and S. kudriavzevii (AWRI 1539 and a hybrid of AWRI 1640 and AWRI 1539 (AWRI 1810 were exposed separately to fungicides pyrimethanil (Pyr, 10 mg/L and fenhexamid (Fhx, 10 mg/L, as well as to the most common toxin produced by moulds on grapes, ochratoxin A (OTA, 5 μg/L, during alcoholic fermentation of Vitis vinifera L. cv. Sauvignon blanc juice. Contaminants were found to strongly impair fermentation performance and metabolic activity of all yeast strains studied. The chemical profile of wine was analyzed by HPLC (volatile acidity, concentrations of ethanol, fructose, glucose, glycerol and organic acids and the aromatic profile was analyzed using a stable isotope dilution technique using GC/MS (ethyl esters, acetates and aromatic alcohols and Kitagawa tubes (H2S. The chemical composition of wine with added contaminants was in all cases significantly different from the control. Of particular note is that the quantity of aromatic compounds produced by yeast was significantly lower. Yeast’s capacity to remove contaminants from wine at the end of the alcoholic fermentation, and after extended contact (7 days was determined. All the strains were able to remove contaminants from the media, moreover, after extended contact, the concentration of contaminants was in most cases lower.

  2. Intraskeletal Chemical Variation Related to Diagenetic Processes: A Late Roman Necropolis Case

    Directory of Open Access Journals (Sweden)

    Gianni Gallello

    2015-12-01

    Full Text Available The aim of the present study was to define a methodological strategy for understanding how post- mortem degradation in bones caused by the environment affects different skeletal parts and for selecting better preserved bone samples employing rare earth elements (REEs analysis and multivariate statistics. It is the first time that REEs are used to evaluate diagenesis impact in archaeological bones. To test our methodological proposal the samples selected belong to adult and young individuals and were obtained from the late-ancient roman necropolis of the c / En Gil (35 samples, located in the downtown area of ?? Valencia City. Therefore, a method for the determination of major elements, trace elements and REEs in bone remains has been developed employing Inductively-Coupled Plasma – Optical Emission Spectroscopy (ICP-OES. Bone samples, mainly rib and femur, from 8 individuals have been studied. Principal Component Analysis (PCA was employed to facilitate the interpretation of the results. Zn/Ca and Sr/Ca parameters show that diet profiles of a population could change depending on the class of bones analyzed.

  3. Phytoecdysteroids and flavonoid glycosides among Chilean and commercial sources of Chenopodium quinoa: variation and correlation to physico-chemical characteristics.

    Science.gov (United States)

    Graf, Brittany L; Rojo, Leonel E; Delatorre-Herrera, Jose; Poulev, Alexander; Calfio, Camila; Raskin, Ilya

    2016-01-30

    Little is known about varietal differences in the content of bioactive phytoecdysteroids (PE) and flavonoid glycosides (FG) from quinoa (Chenopodium quinoa Willd.). The aim of this study was to determine the variation in PE and FG content among 17 distinct quinoa sources and identify correlations to genotypic (highland vs. lowland) and physico-chemical characteristics (seed color, 100-seed weight, protein content, oil content). PE and FG concentrations exhibited over four-fold differences across quinoa sources, ranging from 138 ± 11 µg g(-1) to 570 ± 124 µg g(-1) total PE content and 192 ± 24 µg g(-1) to 804 ± 91 µg g(-1) total FG content. Mean FG content was significantly higher in highland Chilean varieties (583.6 ± 148.9 µg g(-1)) versus lowland varieties (228.2 ± 63.1 µg g(-1)) grown under the same environmental conditions (P = 0.0046; t-test). Meanwhile, PE content was positively and significantly correlated with oil content across all quinoa sources (r = 0.707, P = 0.002; Pearson correlation). FG content may be genotypically regulated in quinoa. PE content may be increased via enhancement of oil content. These findings may open new avenues for the improvement and development of quinoa as a functional food. © 2015 Society of Chemical Industry.

  4. Ab Initio Calculations of 31P NMR Chemical Shielding Anisotropy Tensors in Phosphates: Variations Due to Ring Formation

    Directory of Open Access Journals (Sweden)

    Todd M. Alam

    2002-08-01

    Full Text Available Abstract: Ring formation in phosphate systems is expected to influence both the magnitude and orientation of the phosphorus (31P nuclear magnetic resonance (NMR chemical shielding anisotropy (CSA tensor. Ab initio calculations of the 31P CSA tensor in both cyclic and acyclic phosphate clusters were performed as a function of the number of phosphate tetrahedral in the system. The calculation of the 31P CSA tensors employed the GAUSSIAN 98 implementation of the gauge-including atomic orbital (GIAO method at the Hartree-Fock (HF level. It is shown that both the 31P CSA tensor anisotropy, and the isotropic chemical shielding can be used for the identification of cyclic phosphates. The differences between the 31P CSA tensor in acyclic and cyclic phosphate systems become less pronounced with increasing number of phosphate groups within the ring. The orientation of the principal components for the 31P CSA tensor shows some variation due to cyclization, most notably with the smaller, highly strained ring systems.

  5. Temporal Variations in Physico-Chemical and Microbiological Characteristics of Mvudi River, South Africa

    Directory of Open Access Journals (Sweden)

    Joshua N. Edokpayi

    2015-04-01

    Full Text Available Surface water has been a source of domestic water due to shortage of potable water in most rural areas. This study was carried out to evaluate the level of contamination of Mvudi River in South Africa by measuring turbidity, electrical conductivity (EC, pH, concentrations of nitrate, fluoride, chloride, and sulphate. E. coli and Enterococci were analysed using membrane filtration technique. Average pH, EC and Turbidity values were in the range of 7.2–7.7, 10.5–16.1 mS/m and 1.3–437.5 NTU, respectively. The mean concentrations of fluoride, chloride, nitrate and sulphate for both the wet and the dry seasons were 0.11 mg/L and 0.27 mg/L, 9.35 mg/L and 14.82 mg/L, 3.25 mg/L and 6.87 mg/L, 3.24 mg/L and 0.70 mg/L, respectively. E. coli and Enterococci counts for both the wet and the dry seasons were 4.81 × 103 (log = 3.68 and 5.22 × 103 (log = 3.72, 3.4 × 103 (log = 3.53 and 1.22 × 103 (log = 3.09, per 100 mL of water, respectively. The count of E. coli for both seasons did not vary significantly (p > 0.05 but Enterococci count varied significantly (p < 0.001. All the physico-chemical parameters obtained were within the recommended guidelines of the Department of Water Affairs and Forestry of South Africa and the World Health Organization for domestic and recreational water use for both seasons except turbidity and nitrates. The microbiological parameters exceeded the established guidelines. Mvudi River is contaminated with faecal organisms and should not be used for domestic purposes without proper treatment so as to mitigate the threat it poses to public health.

  6. Collaborative Project: Understanding the Chemical Processes tat Affect Growth rates of Freshly Nucleated Particles

    Energy Technology Data Exchange (ETDEWEB)

    McMurry, Peter [Univ. of Minnesota, Minneapolis, MN (United States); Smuth, James [University Corporation for Atmospheric Research, Irvine, CA (United States)

    2015-11-12

    This final technical report describes our research activities that have, as the ultimate goal, the development of a model that explains growth rates of freshly nucleated particles. The research activities, which combine field observations with laboratory experiments, explore the relationship between concentrations of gas-phase species that contribute to growth and the rates at which those species are taken up. We also describe measurements of the chemical composition of freshly nucleated particles in a variety of locales, as well as properties (especially hygroscopicity) that influence their effects on climate.

  7. Unexpected High Intragenomic Variation in Two of Three Major Pest Thrips Species Does Not Affect Ribosomal Internal Transcribed Spacer 2 (ITS2 Utility for Thrips Identification

    Directory of Open Access Journals (Sweden)

    Vivek Kumar

    2017-10-01

    Full Text Available The mitochondrial cytochrome oxidase I gene (mtCO1 and the ribosomal internal transcribed spacer 2 region (ITS2 are among the most widely used molecular markers for insect taxonomic characterization. Three economically important species of thrips, Scirtothrips dorsalis, Thrips palmi, and Frankliniella occidentalis were selected to examine the extent of intragenomic variation within these two marker regions in the family Thripidae, and determine if this variation would affect the utility of markers in thrips molecular diagnostics. For each species, intragenomic (within individual variation and intergenomic (among individuals variation was assessed by cloning and sequencing PCR-amplified copies. Intergenomic variation was generally higher than intragenomic variation except in cases where intergenomic variation was very low, as in mtCO1 from S. dorsalis and F. occidentalis. Intragenomic variation was detected in both markers in all three of the thrips species, however, 2–3 times more intragenomic variation was observed for ITS2 than mtCO1 in both S. dorsalis and T. palmi. Furthermore, levels of intragenomic variation were low for both of the genes in F. occidentalis. In all of the three thrips species, no sex-based clustering of haplotypes was observed in either marker. Unexpected high intragenomic variation in ITS2 for two of three thrips species did not interfere with thrips diagnostics. However, caution should be taken in applying ITS2 to certain studies of S. dorsalis and T. palmi when high levels of intragenomic variation could be problematic or confounding. In such studies, mtCO1 may be a preferable marker. Possible reasons for discrepancies in intragenomic variation among genomic regions are discussed.

  8. Oxidation of a PAH polluted soil using modified Fenton reaction in unsaturated condition affects biological and physico-chemical properties.

    Science.gov (United States)

    Laurent, F; Cébron, A; Schwartz, C; Leyval, C

    2012-02-01

    A batch experiment was conducted to assess the impact of chemical oxidation using modified Fenton reaction on PAH content and on physico-chemical and biological parameters of an industrial PAH contaminated soil in unsaturated condition. Two levels of oxidant (H(2)O(2), 6 and 65 g kg(-1)) and FeSO(4) were applied. Agronomic parameters, bacterial and fungal density, microbial activity, seed germination and ryegrass growth were assessed. Partial removal of PAHs (14% and 22%) was obtained with the addition of oxidant. The impact of chemical oxidation on PAH removal and soil physico-chemical and biological parameters differed depending on the level of reagent. The treatment with the highest concentration of oxidant decreased soil pH, cation exchange capacity and extractable phosphorus content. Bacterial, fungal, and PAH degrading bacteria densities were also lower in oxidized soil. However a rebound of microbial populations and an increased microbial activity in oxidized soil were measured after 5 weeks of incubation. Plant growth on soil treated by the highest level of oxidant was negatively affected. Copyright © 2011 Elsevier Ltd. All rights reserved.

  9. Efficiency of log wood combustion affects the toxicological and chemical properties of emission particles.

    Science.gov (United States)

    Tapanainen, Maija; Jalava, Pasi I; Mäki-Paakkanen, Jorma; Hakulinen, Pasi; Lamberg, Heikki; Ruusunen, Jarno; Tissari, Jarkko; Jokiniemi, Jorma; Hirvonen, Maija-Riitta

    2012-05-01

    Particulate matter (PM) has been identified as a major environmental pollutant causing severe health problems. Large amounts of the harmful particulate matter (PM) are emitted from residential wood combustion, but the toxicological properties of wood combustion particles are poorly known. To investigate chemical and consequent toxicological characteristics of PM(1) emitted from different phases of batch combustion in four heating appliances. Mouse RAW264.7 macrophages and human BEAS-2B bronchial epithelial cells were exposed for 24 h to different doses (15-300 µg/mL) of wood combustion particles. After the exposure, cytotoxicity, genotoxicity, production of the inflammatory mediators (TNF-α and MIP-2) and effects on the cell cycle were assessed. Furthermore, the detected toxicological responses were compared with the chemical composition of PM(1) samples including PAHs, metals and ions. All the wood combustion samples exerted high cytotoxicity, but only moderate inflammatory activity. The particles emitted from the inefficient phase of batch combustion in the sauna stove (SS) induced the most extensive cytotoxic and genotoxic responses in mammalian cells. Polycyclic aromatic hydrocarbons (PAHs) and other organic compounds in PM(1) samples might have contributed to these effects. Instead, water-soluble metals seemed to participate in the cytotoxic responses triggered by the particles from more efficient batch combustion in the masonry heaters. Overall, the toxicological responses were decreased when the combustion phase was more efficient. Efficiency of batch combustion plays a significant role in the harmfulness of PM even under incomplete wood combustion processes.

  10. Factors Affecting Species Identifications of Blow Fly Pupae Based upon Chemical Profiles and Multivariate Statistics.

    Science.gov (United States)

    Kranz, William; Carroll, Clinton; Dixon, Darren A; Goodpaster, John V; Picard, Christine J

    2017-04-11

    Alternative methods for the identification of species of blow fly pupae have been developed over the years that consist of the analyses of chemical profiles. However, the effect of biotic and abiotic factors that could influence the predictive manner for the tests have not been evaluated. The lipids of blowfly pupae ( Cochliomyia macellaria , Lucilia cuprina , Lucilia sericata , and Phormia regina ) were extracted in pentane, derivatized, and analyzed by total-vaporization solid phase microextraction gas chromatography-mass spectrometry (TV-SPME GC-MS). Peak areas for 26 compounds were analyzed. Here we evaluated one biotic factor (colonization) on four species of blow flies to determine how well a model produced from lipid profiles of colonized flies predicted the species of flies of offspring of wild-caught flies and found very good species identification following 10 generations of inbreeding. When we evaluated four abiotic factors in our fly rearing protocols (temperature, humidity, pupation substrate, and diet), we found that the ability to assign the chemical profile to the correct species was greatly reduced.

  11. RNA sequencing analysis reveals transcriptomic variations in tobacco (Nicotiana tabacum) leaves affected by climate, soil, and tillage factors.

    Science.gov (United States)

    Lei, Bo; Lu, Kun; Ding, Fuzhang; Zhang, Kai; Chen, Yi; Zhao, Huina; Zhang, Lin; Ren, Zhu; Qu, Cunmin; Guo, Wenjing; Wang, Jing; Pan, Wenjie

    2014-04-11

    The growth and development of plants are sensitive to their surroundings. Although numerous studies have analyzed plant transcriptomic variation, few have quantified the effect of combinations of factors or identified factor-specific effects. In this study, we performed RNA sequencing (RNA-seq) analysis on tobacco leaves derived from 10 treatment combinations of three groups of ecological factors, i.e., climate factors (CFs), soil factors (SFs), and tillage factors (TFs). We detected 4980, 2916, and 1605 differentially expressed genes (DEGs) that were affected by CFs, SFs, and TFs, which included 2703, 768, and 507 specific and 703 common DEGs (simultaneously regulated by CFs, SFs, and TFs), respectively. GO and KEGG enrichment analyses showed that genes involved in abiotic stress responses and secondary metabolic pathways were overrepresented in the common and CF-specific DEGs. In addition, we noted enrichment in CF-specific DEGs related to the circadian rhythm, SF-specific DEGs involved in mineral nutrient absorption and transport, and SF- and TF-specific DEGs associated with photosynthesis. Based on these results, we propose a model that explains how plants adapt to various ecological factors at the transcriptomic level. Additionally, the identified DEGs lay the foundation for future investigations of stress resistance, circadian rhythm and photosynthesis in tobacco.

  12. How do low/high height and weight variation affect upper limb movements during manual material handling of industrial boxes?

    Directory of Open Access Journals (Sweden)

    Ana B. Oliveira

    Full Text Available OBJECTIVES: To evaluate the effect of surface height and load weight on upper limb movements and electromyographic (EMG recordings during manual handling performed by both experienced and inexperienced lifter subjects. METHODS: Sixteen experienced and sixteen inexperienced lifters handled a box (both 7 and 15 kg from an intermediate height (waist level to either a high or low surface. Electromyography and video images were recorded during the tasks. The 10th, 50th and 90th percentiles were calculated for the deltoid and biceps muscles, shoulder flexion, shoulder abduction, and elbow flexion movements. Groups, right/left sides, weights and heights were compared. There were no differences between either groups or sides. RESULTS: Weight and height variations affected EMG and posture, although weight had more impact on EMG. Shoulder abduction and flexion movements higher than 60º occurred, particularly for the higher surface. Shoulder flexion was also higher when the box was moved to the low height. This study provides new evidence as shoulder postures during boxes handling on low surfaces had not previously been evaluated. CONCLUSIONS: The high demand of upper limb in manual material handling tasks is clear, particularly for the shoulder. This knowledge can be used by physical therapists to plan better rehabilitation programs for manual material handling-related disorders, particularly focusing on return to work.

  13. [Spatiotemporal variation characteristics and related affecting factors of actual evapotranspiration in the Hun-Taizi River Basin, Northeast China].

    Science.gov (United States)

    Feng, Xue; Cai, Yan-Cong; Guan, De-Xin; Jin, Chang-Jie; Wang, An-Zhi; Wu, Jia-Bing; Yuan, Feng-Hui

    2014-10-01

    Based on the meteorological and hydrological data from 1970 to 2006, the advection-aridity (AA) model with calibrated parameters was used to calculate evapotranspiration in the Hun-Taizi River Basin in Northeast China. The original parameter of the AA model was tuned according to the water balance method and then four subbasins were selected to validate. Spatiotemporal variation characteristics of evapotranspiration and related affecting factors were analyzed using the methods of linear trend analysis, moving average, kriging interpolation and sensitivity analysis. The results showed that the empirical parameter value of 0.75 of AA model was suitable for the Hun-Taizi River Basin with an error of 11.4%. In the Hun-Taizi River Basin, the average annual actual evapotranspiration was 347.4 mm, which had a slightly upward trend with a rate of 1.58 mm · (10 a(-1)), but did not change significantly. It also indicated that the annual actual evapotranspiration presented a single-peaked pattern and its peak value occurred in July; the evapotranspiration in summer was higher than in spring and autumn, and it was the smallest in winter. The annual average evapotranspiration showed a decreasing trend from the northwest to the southeast in the Hun-Taizi River Basin from 1970 to 2006 with minor differences. Net radiation was largely responsible for the change of actual evapotranspiration in the Hun-Taizi River Basin.

  14. Determining residential energy consumption-based CO2 emissions and examining the factors affecting the variation in Ankara, Turkey

    Science.gov (United States)

    Kus, Melike; Akan, Perihan; Aydinalp Koksal, Merih; Gullu, Gulen

    2017-11-01

    Energy demand of Turkey has been showing a remarkable increase in the last two decades due to rapid increase in population and changes in consumption trends. In parallel to the increase in energy demand, the CO2 emissions in Turkey are also increasing dramatically due to high usage of fossil fuels. CO2 emissions from the residential sector covers almost one fourth of the total sectoral emissions. In this study, CO2 emissions from the residential sector are estimated, and the factors affecting the emission levels are determined for the residential sector in Ankara, Turkey. In this study, detailed surveys are conducted to more than 400 households in Ankara. Using the information gathered from the surveys, the CO2 emissions associated with energy consumption of the households are calculated using the methodology outlined at IPCC. The statistical analyses are carried out using household income, dwelling characteristics, and household economic and demographic data to determine the factors causing the variation in emission levels among the households. The results of the study present that the main factors impacting the amount of total energy consumption and associated CO2 emissions are household income, dwelling construction year, age, education level of the household, and net footage of the dwelling.

  15. RNA Sequencing Analysis Reveals Transcriptomic Variations in Tobacco (Nicotiana tabacum Leaves Affected by Climate, Soil, and Tillage Factors

    Directory of Open Access Journals (Sweden)

    Bo Lei

    2014-04-01

    Full Text Available The growth and development of plants are sensitive to their surroundings. Although numerous studies have analyzed plant transcriptomic variation, few have quantified the effect of combinations of factors or identified factor-specific effects. In this study, we performed RNA sequencing (RNA-seq analysis on tobacco leaves derived from 10 treatment combinations of three groups of ecological factors, i.e., climate factors (CFs, soil factors (SFs, and tillage factors (TFs. We detected 4980, 2916, and 1605 differentially expressed genes (DEGs that were affected by CFs, SFs, and TFs, which included 2703, 768, and 507 specific and 703 common DEGs (simultaneously regulated by CFs, SFs, and TFs, respectively. GO and KEGG enrichment analyses showed that genes involved in abiotic stress responses and secondary metabolic pathways were overrepresented in the common and CF-specific DEGs. In addition, we noted enrichment in CF-specific DEGs related to the circadian rhythm, SF-specific DEGs involved in mineral nutrient absorption and transport, and SF- and TF-specific DEGs associated with photosynthesis. Based on these results, we propose a model that explains how plants adapt to various ecological factors at the transcriptomic level. Additionally, the identified DEGs lay the foundation for future investigations of stress resistance, circadian rhythm and photosynthesis in tobacco.

  16. CHEMICALS

    CERN Multimedia

    Medical Service

    2002-01-01

    It is reminded that all persons who use chemicals must inform CERN's Chemistry Service (TIS-GS-GC) and the CERN Medical Service (TIS-ME). Information concerning their toxicity or other hazards as well as the necessary individual and collective protection measures will be provided by these two services. Users must be in possession of a material safety data sheet (MSDS) for each chemical used. These can be obtained by one of several means : the manufacturer of the chemical (legally obliged to supply an MSDS for each chemical delivered) ; CERN's Chemistry Service of the General Safety Group of TIS ; for chemicals and gases available in the CERN Stores the MSDS has been made available via EDH either in pdf format or else via a link to the supplier's web site. Training courses in chemical safety are available for registration via HR-TD. CERN Medical Service : TIS-ME :73186 or service.medical@cern.ch Chemistry Service : TIS-GS-GC : 78546

  17. Chemical expansion affected oxygen vacancy stability in different oxide structures from first principles calculations

    Energy Technology Data Exchange (ETDEWEB)

    Aidhy, Dilpuneet S.; Liu, Bin; Zhang, Yanwen; Weber, William J.

    2015-03-01

    We study the chemical expansion for neutral and charged oxygen vacancies in fluorite, rocksalt, perovskite and pyrochlores materials using first principles calculations. We show that the neutral oxygen vacancy leads to lattice expansion whereas the charged vacancy leads to lattice contraction. In addition, we show that there is a window of strain within which an oxygen vacancy is stable; beyond that range, the vacancy can become unstable. Using CeO2|ZrO2 interface structure as an example, we show that the concentration of oxygen vacancies can be manipulated via strain, and the vacancies can be preferentially stabilized. These results could serve as guiding principles in predicting oxygen vacancy stability in strained systems and in the design of vacancy stabilized materials.

  18. Final Report: "Collaborative Project. Understanding the Chemical Processes That Affect Growth Rates of Freshly Nucleated Particles"

    Energy Technology Data Exchange (ETDEWEB)

    Smith, James N. [NCAR, Boulder, CO (United States); McMurry, Peter H. [NCAR, Boulder, CO (United States)

    2015-11-12

    This final technical report describes our research activities that have, as the ultimate goal, the development of a model that explains growth rates of freshly nucleated particles. The research activities, which combine field observations with laboratory experiments, explore the relationship between concentrations of gas-phase species that contribute to growth and the rates at which those species are taken up. We also describe measurements of the chemical composition of freshly nucleated particles in a variety of locales, as well as properties (especially hygroscopicity) that influence their effects on climate. Our measurements include a self-organized, DOE-ARM funded project at the Southern Great Plains site, the New Particle Formation Study (NPFS), which took place during spring 2013. NPFS data are available to the research community on the ARM data archive, providing a unique suite observations of trace gas and aerosols that are associated with the formation and growth of atmospheric aerosol particles.

  19. Dryland soil chemical properties and crop yields affected by long-term tillage and cropping sequence.

    Science.gov (United States)

    Sainju, Upendra M; Allen, Brett L; Caesar-TonThat, Thecan; Lenssen, Andrew W

    2015-01-01

    Information on the effect of long-term management on soil nutrients and chemical properties is scanty. We examined the 30-year effect of tillage frequency and cropping sequence combination on dryland soil Olsen-P, K, Ca, Mg, Na, SO4-S, and Zn concentrations, pH, electrical conductivity (EC), and cation exchange capacity (CEC) at the 0-120 cm depth and annualized crop yield in the northern Great Plains, USA. Treatments were no-till continuous spring wheat (Triticum aestivum L.) (NTCW), spring till continuous spring wheat (STCW), fall and spring till continuous spring wheat (FSTCW), fall and spring till spring wheat-barley (Hordeum vulgare L., 1984-1999) followed by spring wheat-pea (Pisum sativum L., 2000-2013) (FSTW-B/P), and spring till spring wheat-fallow (STW-F, traditional system). At 0-7.5 cm, P, K, Zn, Na, and CEC were 23-60% were greater, but pH, buffer pH, and Ca were 6-31% lower in NTCW, STCW, and FSTW-B/P than STW-F. At 7.5-15 cm, K was 23-52% greater, but pH, buffer pH, and Mg were 3-21% lower in NTCW, STCW, FSTCW, FSTW-B/P than STW-F. At 60-120 cm, soil chemical properties varied with treatments. Annualized crop yield was 23-30% lower in STW-F than the other treatments. Continuous N fertilization probably reduced soil pH, Ca, and Mg, but greater crop residue returned to the soil increased P, K, Na, Zn, and CEC in NTCW and STCW compared to STW-F. Reduced tillage with continuous cropping may be adopted for maintaining long-term soil fertility and crop yields compared with the traditional system.

  20. Development of standards for chemical and biological decontamination of buildings and structures affected by terrorism

    Energy Technology Data Exchange (ETDEWEB)

    Lumley, T.C.; Volchek, K.; Fingas, M. [Environment Canada, Ottawa, ON (Canada). Emergencies Science and Technology Division, Environmental Technology Centre, Science and Technology Branch; Hay, A.W.M. [Leeds Univ., Leeds (United Kingdom)

    2006-07-01

    Currently, there are no suitable standards for determining levels of safety when reoccupying a building that has been recommissioned following a biological or chemical attack. For that reason, this study focused on developing clean-up standards for decontaminating buildings and construction materials after acts of terrorism. Several parameters must be assessed when determining the course of action to decontaminate toxic agents and to rehabilitate facilities. First, the hazardous substance must be positively identified along with the degree of contamination and information on likely receptors. Potential exposure route is also a key consideration in the risk assessment process. A key objective of the study was to develop specific guidelines for ascertaining and defining clean. In particular, standards for chemical and biological agents that pose a real or potential risk for use as agents of terrorism will be developed. The selected agents for standards development were ammonia, fentanyl, malathion, mustard gas, potassium cyanide, ricin, sarin, hepatitis A virus, and bacillus anthracis. The standards will be developed by establishing the relationship between the amount of exposure and expected health effects; assessing real and potential risks by identifying individuals at risk and consideration of all exposure routes; and, characterizing the risk to determine the potential for toxicity or infectivity. For non-carcinogens, this was done through the analysis of other known guidelines. Cancer-slope factors will be considered for carcinogens. The standards will be assessed in the laboratory using animal models. The guidelines and standards are intended for first-responders and are scheduled for development by the end of 2006. 15 refs., 3 tabs.

  1. Stratospheric O3 changes during 2001–2010: the small role of solar flux variations in a chemical transport model

    Directory of Open Access Journals (Sweden)

    S. S. Dhomse

    2013-10-01

    Full Text Available Solar spectral fluxes (or irradiance measured by the SOlar Radiation and Climate Experiment (SORCE show different variability at ultraviolet (UV wavelengths compared to other irradiance measurements and models (e.g. NRL-SSI, SATIRE-S. Some modelling studies have suggested that stratospheric/lower mesospheric O3 changes during solar cycle 23 (1996–2008 can only be reproduced if SORCE solar fluxes are used. We have used a 3-D chemical transport model (CTM, forced by meteorology from the European Centre for Medium-Range Weather Forecasts (ECMWF, to simulate middle atmospheric O3 using three different solar flux data sets (SORCE, NRL-SSI and SATIRE-S. Simulated O3 changes are compared with Microwave Limb Sounder (MLS and Sounding of the Atmosphere using Broadband Emission Radiometry (SABER satellite data. Modelled O3 anomalies from all solar flux data sets show good agreement with the observations, despite the different flux variations. The off-line CTM reproduces these changes through dynamical information contained in the analyses. A notable feature during this period is a robust positive solar signal in the tropical middle stratosphere, which is due to realistic dynamical changes in our simulations. Ozone changes in the lower mesosphere cannot be used to discriminate between solar flux data sets due to large uncertainties and the short time span of the observations. Overall this study suggests that, in a CTM, the UV variations detected by SORCE are not necessary to reproduce observed stratospheric O3 changes during 2001–2010.

  2. Variation in fish mercury concentrations in streams of the Adirondack region, New York: A simplified screening approach using chemical metrics

    Science.gov (United States)

    Burns, Douglas A.; Riva-Murray, Karen

    2018-01-01

    Simple screening approaches for the neurotoxicant methylmercury (MeHg) in aquatic ecosystems may be helpful in risk assessments of natural resources. We explored the development of such an approach in the Adirondack Mountains of New York, USA, a region with high levels of MeHg bioaccumulation. Thirty-six perennial streams broadly representative of 1st and 2nd order streams in the region were sampled during summer low flow and analyzed for several solutes and for Hg concentrations in fish. Several landscape and chemical metrics that are typically strongly related to MeHg concentrations in aquatic biota were explored for strength of association with fish Hg concentrations. Data analyses were based on site mean length-normalized and standardized Hg concentrations (assumed to be dominantly MeHg) in whole juvenile and adult Brook Trout Salvelinus fontinalis, Creek Chub Semotilus atromaculatus, Blacknose Dace Rhinichthys atratulus, and Central Mudminnow Umbra limi, as well as on multi-species z-scores. Surprisingly, none of the landscape metrics was related significantly to regional variation in fish Hg concentrations or to z-scores across the study streams. In contrast, several chemical metrics including dissolved organic carbon (DOC) concentrations, sulfate concentrations (SO42−), pH, ultra-violet absorbance (UV254), and specific ultra-violet absorbance were significantly related to regional variation in fish Hg concentrations. A cluster analysis based on DOC, SO42−, and pH identified three distinct groups of streams: (1) high DOC, acidic streams, (2) moderate DOC, slightly acidic streams, and (3) low DOC circum-neutral streams with relatively high SO42−. Preliminary analysis indicated no significant difference in fish Hg z-scores between the moderate and high DOC groups, so these were combined for further analysis. The resulting two groups showed strong differences (p 6.9 mg/L, SO42− 0.31 cm−1 were tested as thresholds to identify Adirondack

  3. Field-scale Variation in Colloid Dispersibility and Transport: Multiple Linear Regressions to Soil Physico-Chemical and Structural Properties.

    Science.gov (United States)

    Norgaard, Trine; Moldrup, P; Ferré, T P A; Katuwal, S; Olsen, P; de Jonge, L W

    2014-09-01

    Water-dispersible soil colloids (WDC) act as carriers for sorbing chemicals in macroporous soils and hence constitute a significant risk for the aquatic environment. The prediction of WDC readily available for facilitated chemical transport is an unsolved challenge. This study identifies key parameters and predictive indicators for assessing field-scale variation of WDC. Samples representing three measurement scales (1- to 2-mm aggregates, intact 100-cm rings, and intact 6283 cm columns) were retrieved from the topsoil of a 1.69-ha agricultural field in a 15-m by 15-m grid to determine colloid dispersibility, mobilization, and transport. The amount of WDC was determined using (i) a laser diffraction method on 1- to 2-mm aggregates and (ii) an end-over-end shaking method on 100-cm intact rings. The accumulated amount of colloids leached from 20-cm by 20-cm intact columns was determined as a measure of the integrated colloid mobilization and transport. The WDC and the accumulated colloid transport were higher in samples from the northern part of the field. Using multiple linear regression (MLR) analyses, WDC or amount of colloids transported were predicted at the three measurement scales from 24 measured, geo-referenced parameters to identify parameters that could serve as indicator parameters for screening for colloid dispersibility, mobilization, and transport. The MLR analyses were performed at each sample scale using all, only northern, and only southern field locations. Generally, the predictive power of the regression models was best on the smallest 1- to 2-mm aggregate scale. Overall, our results suggest that different drivers controlled colloid dispersibility and transport at the three measurement scales and in the two subareas of the field. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  4. Essential oil variation in the populations of Artemisia spicigera from northwest of Iran: chemical composition and antibacterial activity.

    Science.gov (United States)

    Chehregani, Abdolkarim; Atri, Morteza; Yousefi, Somayeh; Albooyeh, Zahra; Mohsenzadeh, Fariba

    2013-02-01

    Artemisia spicigera C. Koch (Asteraceae) is a perennial shrubby herb and is generally distributed in Armenia, Iran, and Middle Anatolia. This species traditionally has been used in medicines. The aim of this research is to study the chemical composition and antibacterial activity of essential oils from Artemisia spicigera populations in northwest of Iran. The essential oil of A. spicigera was obtained by hydrodistillation from eight populations collected from different regions of East Azerbaijan and West Azerbaijan provinces (Iran) and analyzed by gas chromatography-mass spectrometry (GC-MS). The antibacterial activity of the oils was investigated against four Gram-positive and four Gram-negative bacteria using MIC determinations and the agar-gel diffusion method. Fourteen compounds were identified as the main components of the essential oils and the most abundant constituents are 1,8-cineole, camphor, α-thujone, camphene, β-thujone and p-cymene. Essential oil of population No. 1 showed the highest activity against Escherichia coli, Enterobacter aerogenes, Serratia marcescens and Staphylococcus aureus but the highest activity against St. saprophyticus, Bacillus megaterium, and B. cereus was found with population No. 6 and for Citrobacter amalonaficus with population No. 5. MIC values of essential oils ranged from 6 µg/mL against Bacillus megaterium to 12 µg/mL against Citrobacter amalonaficus. This study demonstrates the occurrence of 1,8-cineole/camphor/camphene chemotype of A. spicigera but there is also significant chemical variation between the studied populations. The findings showed the studied oils have good antibacterial activity, and thus potential to be used as natural health products.

  5. Exposure of wood in floodplains affects its chemical quality and its subsequent breakdown in streams.

    Science.gov (United States)

    del Campo, Rubén; Gómez, Rosa

    2016-02-01

    In stream ecosystems, coarse organic matter from the riparian vegetation, a key food resource, is often retained in the floodplains before reaching the channel. During floodplain exposure, organic matter can be affected by abiotic and biotic processes ("preconditioning"), which alter its quality and affect its subsequent decomposition in streams. We analyzed the effect of floodplain preconditioning on wood quality (lignin, C, N, P, K, among others), and its subsequent aquatic breakdown, paying special attention to microbial activity. We simulated preconditioned standard wooden sticks on one arid stream floodplain for 3 and 4 months, and then monitored their breakdown in three different streams, together with control (non-preconditioned) sticks. Preconditioning reduced lignin mass and C:N and lignin:N ratios, caused the leaching of soluble nutrients such as P and K, as well as N immobilization by microbes. These changes enhanced the breakdown of wood in the first week of immersion, but had no effect on breakdown rates after 4 months of incubation in the streams, although N immobilization was diminished. Our results suggest that terrestrial preconditioning could alter the role of wood as a long-lasting nutrients and energy source for freshwater ecosystem. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Chemical and spectroscopic characteristics of the wood of Vitis vinifera cv. Sangiovese affected by esca disease.

    Science.gov (United States)

    Agrelli, Diana; Amalfitano, Carmine; Conte, Pellegrino; Mugnai, Laura

    2009-12-23

    Chemical and spectroscopic analyses ((13)C cross-polarization-magic angle spinning NMR and attenuated total reflection Fourier transform infrared spectroscopies) were carried out on the wood of Vitis vinifera cv. Sangiovese with brown-red discoloration and black streaks caused by esca disease. The analyses of the brown-red wood revealed the destruction of hemicelluloses and noncrystalline cellulose as well as modifications in the pectic and ligninic wood fractions. The pectic fraction consisted of carbohydrates associated with polyphenols. The lignin fraction exhibited only a few changes in the aromatic systems and a partial demethylation, and it appeared to be associated with condensed phenolic components probably arising from response polyphenols. The degradation of hemicelluloses and noncrystalline cellulose in brown-red wood, where the pathogens Phaeoacremonium aleophilum and Phaeomoniella chlamydospora prevail with respect to the other fungus Fomitiporia mediterranea, was consistent with reports on the degradative activity of such fungi in vitro carried out on model substrates. The observed alterations could also be attributed to the radical oxidation process caused by the oxidative response of defense itself triggered by infection, as suggested by the accumulation of postinfectional compounds. The analyses of wood tissue with black streaks showed less marked deterioration; here, an increase in pectic and phenolic substances, which probably accumulate in the xylem vessels as a response to the infection, was observed.

  7. Factors affecting variations in the detailed fatty acid profile of Mediterranean buffalo milk determined by 2-dimensional gas chromatography.

    Science.gov (United States)

    Pegolo, S; Stocco, G; Mele, M; Schiavon, S; Bittante, G; Cecchinato, A

    2017-04-01

    Buffalo milk is the world's second most widely produced milk, and increasing attention is being paid to its composition, particularly the fatty acid profile. The objectives of the present study were (1) to characterize the fatty acid composition of Mediterranean buffalo milk, and (2) to investigate potential sources of variation in the buffalo milk fatty acid profile. We determined the profile of 69 fatty acid traits in 272 individual samples of Mediterranean buffalo milk using gas chromatography. In total, 51 individual fatty acids were identified: 24 saturated fatty acids, 13 monounsaturated fatty acids, and 14 polyunsaturated fatty acids. The major individual fatty acids in buffalo milk were in the order 16:0, 18:1 cis-9, 14:0, and 18:0. Saturated fatty acids were the predominant fraction in buffalo milk fat (70.49%); monounsaturated and polyunsaturated fatty acids were at 25.95 and 3.54%, respectively. Adopting a classification based on carbon-chain length, we found that medium-chain fatty acids (11-16 carbons) represented the greater part (53.7%) of the fatty acid fraction of buffalo milk, whereas long-chain fatty acids (17-24 carbons) and short-chain fatty acids (4-10 carbons) accounted for 32.73 and 9.72%, respectively. The n-3 and n-6 fatty acids were 0.46 and 1.77%, respectively. The main conjugated linoleic acid, rumenic acid, represented 0.45% of total milk fatty acids. Herd/test date and stage of lactation were confirmed as important sources of variation in the fatty acid profile of buffalo milk. The percentages of short-chain and medium-chain fatty acids in buffalo milk increased in early lactation (+0.6 and +3.5%, respectively), whereas long-chain fatty acids decreased (-4.2%). The only exception to this pattern was butyric acid, which linearly decreased from the beginning of lactation, confirmation that its synthesis is independent of malonyl-CoA. These results seem to suggest that in early lactation the mobilization of energy reserves may have less

  8. Temporal and vertical variations of aerosol physical and chemical properties over West Africa: AMMA aircraft campaign in summer 2006

    Directory of Open Access Journals (Sweden)

    A. Matsuki

    2010-09-01

    Full Text Available While the Sahelian belt in West Africa stretches in the border between the global hot-spots of mineral dust and biomass burning aerosols, the presence of West African Monsoon is expected to create significant vertical and temporal variations in the regional aerosol properties through transport and mixing of particles from various sources (mineral dust, biomass burning, sulfates, sea salt. In order to improve our understanding of the evolution of the aerosol-cloud system over such region across the onset of the summer monsoon, the French ATR-42 research aircraft was deployed in Niamey, Niger (13°30' N, 02°05' E in summer 2006, during the three special observation periods (SOPs of the African Monsoon Multidisciplinary Analysis (AMMA project. These three SOPs covered both dry and wet periods before and after the onset of the Western African Monsoon.

    State of the art physico-chemical aerosol measurements on the ATR-42 showed a notable seasonal transition in averaged number size distributions where (i the Aitken mode is dominating over the accumulation mode during the dry season preceding the monsoon arrival and (ii the accumulation mode increasingly gained importance after the onset of the West African monsoon and even dominated the Aitken mode after the monsoon had fully developed. The parameters for the mean log-normal distributions observed in respective layers characterized by the different wind regimes (monsoon layer, SAL, free troposphere are presented, together with the major particle compositions found in the accumulation mode particles. Thereby, results of this study should facilitate radiative transfer calculations, validation of satellite remote sensors, and detailed transport modeling by partners within and outside the AMMA community.

    Extended analysis of the chemical composition of single aerosol particles by a transmission electron microscope (TEM coupled to an energy dispersive X-ray spectrometer (EDX revealed

  9. Accurately Assessing the Risk of Schizophrenia Conferred by Rare Copy-Number Variation Affecting Genes with Brain Function

    Science.gov (United States)

    Raychaudhuri, Soumya; Korn, Joshua M.; McCarroll, Steven A.; Altshuler, David; Sklar, Pamela; Purcell, Shaun; Daly, Mark J.

    2010-01-01

    Investigators have linked rare copy number variation (CNVs) to neuropsychiatric diseases, such as schizophrenia. One hypothesis is that CNV events cause disease by affecting genes with specific brain functions. Under these circumstances, we expect that CNV events in cases should impact brain-function genes more frequently than those events in controls. Previous publications have applied “pathway” analyses to genes within neuropsychiatric case CNVs to show enrichment for brain-functions. While such analyses have been suggestive, they often have not rigorously compared the rates of CNVs impacting genes with brain function in cases to controls, and therefore do not address important confounders such as the large size of brain genes and overall differences in rates and sizes of CNVs. To demonstrate the potential impact of confounders, we genotyped rare CNV events in 2,415 unaffected controls with Affymetrix 6.0; we then applied standard pathway analyses using four sets of brain-function genes and observed an apparently highly significant enrichment for each set. The enrichment is simply driven by the large size of brain-function genes. Instead, we propose a case-control statistical test, cnv-enrichment-test, to compare the rate of CNVs impacting specific gene sets in cases versus controls. With simulations, we demonstrate that cnv-enrichment-test is robust to case-control differences in CNV size, CNV rate, and systematic differences in gene size. Finally, we apply cnv-enrichment-test to rare CNV events published by the International Schizophrenia Consortium (ISC). This approach reveals nominal evidence of case-association in neuronal-activity and the learning gene sets, but not the other two examined gene sets. The neuronal-activity genes have been associated in a separate set of schizophrenia cases and controls; however, testing in independent samples is necessary to definitively confirm this association. Our method is implemented in the PLINK software package

  10. Chemical Variability and Biological Activities of Brassica rapa var. rapifera Parts Essential Oils Depending on Geographic Variation and Extraction Technique.

    Science.gov (United States)

    Saka, Boualem; Djouahri, Abderrahmane; Djerrad, Zineb; Terfi, Souhila; Aberrane, Sihem; Sabaou, Nasserdine; Baaliouamer, Aoumeur; Boudarene, Lynda

    2017-06-01

    In the present work, the Brassica rapa var. rapifera parts essential oils and their antioxidant and antimicrobial activities were investigated for the first time depending on geographic origin and extraction technique. Gas-chromatography (GC) and GC/mass spectrometry (MS) analyses showed several constituents, including alcohols, aldehydes, esters, ketones, norisoprenoids, terpenic, nitrogen and sulphur compounds, totalizing 38 and 41 compounds in leaves and root essential oils, respectively. Nitrogen compounds were the main volatiles in leaves essential oils and sulphur compounds were the main volatiles in root essential oils. Qualitative and quantitative differences were found among B. rapa var. rapifera parts essential oils collected from different locations and extracted by hydrodistillation and microwave-assisted hydrodistillation techniques. Furthermore, our findings showed a high variability for both antioxidant and antimicrobial activities. The highlighted variability reflects the high impact of plant part, geographic variation and extraction technique on chemical composition and biological activities, which led to conclude that we should select essential oils to be investigated carefully depending on these factors, in order to isolate the bioactive components or to have the best quality of essential oil in terms of biological activities and preventive effects in food. © 2017 Wiley-VHCA AG, Zurich, Switzerland.

  11. Growth rate variation of the stalked barnacle Pollicipes pollicipes (Crustacea: Cirripedia using calcein as a chemical marker

    Directory of Open Access Journals (Sweden)

    David Jacinto

    2015-03-01

    Full Text Available This study describes the use of calcein as a chemical tagging methodology to estimate growth rate variation of the stalked barnacle Pollicipes pollicipes, an ecologically important intertidal species and economic resource, in SW Portugal. Calcein tagging had a high success rate (94% in marking both juvenile and adult barnacles for a period of 2.5 months, providing a valuable method for obtaining reliable data in growth studies of P. pollicipes. Growth rate decreased with barnacle size and was highly variable amongst individuals, particularly in smaller barnacles. No effect of shore level on barnacle growth was detected. Growth rates were higher in smaller juvenile barnacles, peaking at a 1.1-mm monthly increment in rostro-carinal length (RC for individuals with RC=5 mm, and decreased with barnacle size (monthly growth rates of 0.5 mm for adult barnacles with RC~12.5 mm. Growth rates observed in adults with commercial interest (RC ≥ 18 mm was < 0.25 mm per month. The advantages of tagging P. pollicipes with calcein were the possibility of mass marking individual barnacles of different size cohorts within a short period (less than 1 day of manipulation; and reduced time of fieldwork, which is very important because this species inhabits very exposed rocky shores.

  12. Factors affecting the chemical durability of glass used in the pharmaceutical industry.

    Science.gov (United States)

    Iacocca, Ronald G; Toltl, Nick; Allgeier, M; Bustard, B; Dong, Xia; Foubert, M; Hofer, J; Peoples, S; Shelbourn, T

    2010-09-01

    Delamination, or the generation of glass flakes in vials used to contain parenteral drug products, continues to be a persistent problem in the pharmaceutical industry. To understand all of the factors that might contribute to delamination, a statistical design of experiments was implemented to describe this loss of chemical integrity for glass vials. Phase I of this study focused on the effects of thermal exposure (prior to product filling) on the surface chemistry of glass vials. Even though such temperatures are below the glass transition temperature for the glass, and parenteral compounds are injected directly into the body, data must be collected to show that the glass was not phase separating. Phase II of these studies examined the combined effects of thermal exposure, glass chemistry, and exposure to pharmaceutically relevant molecules on glass delamination. A variety of tools was used to examine the glass and the solution contained in the vial including: scanning electron microscopy and dynamic secondary ion mass spectroscopy for the glass; and visual examination, pH measurements, laser particle counting, and inductively coupled plasma-optical emission spectrometry for the analysis of the solution. The combined results of phase I and II showed depyrogenation does not play a significant role in delamination. Terminal sterilization, glass chemistry, and solution chemistry are the key factors in the generation of glass flakes. Dissolution of silica may be an effective indicator that delamination will occur with a given liquid stored in glass. Finally, delamination should not be defined by the appearance of visible glass particulates. There is a mechanical component in the delamination process whereby the flakes must break away from the interior vial surface. Delamination should be defined by the observation of flakes on the interior surface of the vial, which can be detected by several other analytical techniques.

  13. Environmental Growing Conditions in Five Production Systems Induce Stress Response and Affect Chemical Composition of Cocoa (Theobroma cacao L.) Beans.

    Science.gov (United States)

    Niether, Wiebke; Smit, Inga; Armengot, Laura; Schneider, Monika; Gerold, Gerhard; Pawelzik, Elke

    2017-11-29

    Cocoa beans are produced all across the humid tropics under different environmental conditions provided by the region but also by the season and the type of production system. Agroforestry systems compared to monocultures buffer climate extremes and therefore provide a less stressful environment for the understory cocoa, especially under seasonally varying conditions. We measured the element concentration as well as abiotic stress indicators (polyamines and total phenolic content) in beans derived from five different production systems comparing monocultures and agroforestry systems and from two harvesting seasons. Concentrations of N, Mg, S, Fe, Mn, Na, and Zn were higher in beans produced in agroforestry systems with high stem density and leaf area index. In the dry season, the N, Fe, and Cu concentration of the beans increased. The total phenolic content increased with proceeding of the dry season while other abiotic stress indicators like spermine decreased, implying an effect of the water availability on the chemical composition of the beans. Agroforestry systems did not buffer the variability of stress indicators over the seasons compared to monocultures. The effect of environmental growing conditions on bean chemical composition was not strong but can contribute to variations in cocoa bean quality.

  14. Seasonal Variation, Chemical Composition, and Analgesic and Antimicrobial Activities of the Essential Oil from Leaves of Tetradenia riparia (Hochst. Codd in Southern Brazil

    Directory of Open Access Journals (Sweden)

    Gilberto Alves Ferreira

    2010-08-01

    Full Text Available The seasonal variation of the chemical composition of the essential oil from fresh leaves of Tetradenia riparia (Hochst. Codd grown in southern Brazil was analyzed by GC-MS, and the analgesic and antimicrobial activities of this oil were assayed. The yield of essential oil ranged from 0.17% to 0.26%, with the maximum amount in winter and the minimum in spring. The results obtained from principal components analysis (PCA revealed the existence of high chemical variability in the different seasons. The samples were clearly discriminated into three groups: winter, autumn, and spring-summer. Samples collected during winter contained the highest percentages of calyculone (24.70%, abietadiene (13.54%, and viridiflorol (4.20%. In autumn, the major constituents were ledol (8.74% and cis-muurolol-5-en-4-α-ol (13.78%. Samples collected in spring-summer contained the highest percentages of fenchone (12.67%, 14-hydroxy-9-epi-caryophyllene (24.36%, and α-cadinol (8.33%. Oxygenated sesquiterpenes were predominant in all the samples analyzed. The observed chemovariation might be environmentally determined by a seasonal influence. The essential oil, when given orally at a dose of 200 mg/kg, exhibited good analgesic activity on acetic acid-induced writhing in mice, inhibiting the constrictions by 38.94% to 46.13%, and this effect was not affected by seasonal variation. The antimicrobial activity of the essential oil against the bacterial strains: Staphylococcus aureus, Bacillus subtilis, Enterococcus faecalis, Escherichia coli, Salmonella enterica, Pseudomonas aeruginosa, Klebsiella pneumonia, Proteus mirabilis, Morganella morganii, and Enterobacter cloacae, and the pathogenic fungus Candida albicans was assessed by the disc diffusion method and determination of the minimum inhibitory concentration. The results obtained, followed by measurement of the minimum inhibitory concentration (MIC, indicated that S. aureus, B. subtilis, and Candida albicans were the

  15. Do intraindividual variation in disease progression and the ensuing tight window of opportunity affect estimation of screening benefits?

    NARCIS (Netherlands)

    Koffijberg, Hendrik; Rinkel, Gabriel; Buskens, Erik

    Background. The effects of variation in disease progression between individuals on the effectiveness of screening have been assessed extensively in the literature. For several diseases, progression may also vary within individuals over time. The authors study the effects of intraindividual variation

  16. Do Intraindividual Variation in Disease Progression and the Ensuing Tight Window of Opportunity Affect Estimation of Screening Benefits?

    NARCIS (Netherlands)

    Koffijberg, Hendrik; Rinkel, Gabriel; Buskens, Erik

    2009-01-01

    Background. The effects of variation in disease progression between individuals on the effectiveness of screening have been assessed extensively in the literature. For several diseases, progression may also vary within individuals over time. The authors study the effects of intraindividual variation

  17. Microstructural Characterization of Red Mud as Affected by Inorganic and Organic Chemicals Permeation

    Science.gov (United States)

    Rubinos, David A.; Valcárcel, Víctor; Spagnoli, Giovanni; Barral, María Teresa

    2017-09-01

    The microstructural characteristics of red mud (RM), especially specific surface area (SSA) and mesoporosity, and the effects of various representative fluids, namely methanol (80% v/v), trichloroethylene (TCE) (1100 mg/L), acetic acid (pH 2), and CaCl2 (5% w/v) aqueous solutions, were studied using N2-gas adsorption. The effect of compaction was also assessed. RM powder exhibited a moderate Brunauer-Emmet-Teller (BET)-SSA and is mostly a mesoporous (large mesopores, 200-500 Å) and a macroporous material. Compaction affected the macro and large, but not the fine, mesopores. Among the fluids, CaCl2 and acetic acid induced notable and opposing changes in RM microstructural characteristics. CaCl2 decreased SSA and suppressed fine mesoporosity, whereas acetic acid greatly enhanced them. Fractal analysis further indicated increasing surface roughness and heterogeneity of pore structure during acid exposure, altogether envisaging an improvement of adsorption capacity and a decrease of permeability of the RM.

  18. Ecological interactions affecting population-level responses to chemical stress in Mesocyclops leuckarti.

    Science.gov (United States)

    Kulkarni, Devdutt; Hommen, Udo; Schäffer, Andreas; Preuss, Thomas G

    2014-10-01

    Higher tiers of ecological risk assessment (ERA) consider population and community-level endpoints. At the population level, the phenomenon of density dependence is one of the most important ecological processes that influence population dynamics. In this study, we investigated how different mechanisms of density dependence would influence population-level ERA of the cyclopoid copepod Mesocyclops leuckarti under toxicant exposure. We used a combined approach of laboratory experiments and individual-based modelling. An individual-based model was developed for M. leuckarti to simulate population dynamics under triphenyltin exposure based on individual-level ecological and toxicological data from laboratory experiments. The study primarily aimed to-(1) determine which life-cycle processes, based on feeding strategies, are most significant in determining density dependence (2) explore how these mechanisms of density dependence affect extrapolation from individual-level effects to the population level under toxicant exposure. Model simulations showed that cannibalism of nauplii that were already stressed by TPT exposure contributed to synergistic effects of biotic and abiotic factors and led to a twofold stress being exerted on the nauplii, thereby resulting in a higher population vulnerability compared to the scenario without cannibalism. Our results suggest that in population-level risk assessment, it is easy to underestimate toxicity unless underlying ecological interactions including mechanisms of population-level density regulation are considered. This study is an example of how a combined approach of experiments and mechanistic modelling can lead to a thorough understanding of ecological processes in ecotoxicology and enable a more realistic ERA. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Emissions from Electronic Cigarettes: Key Parameters Affecting the Release of Harmful Chemicals.

    Science.gov (United States)

    Sleiman, Mohamad; Logue, Jennifer M; Montesinos, V Nahuel; Russell, Marion L; Litter, Marta I; Gundel, Lara A; Destaillats, Hugo

    2016-09-06

    Use of electronic cigarettes has grown exponentially over the past few years, raising concerns about harmful emissions. This study quantified potentially toxic compounds in the vapor and identified key parameters affecting emissions. Six principal constituents in three different refill "e-liquids" were propylene glycol (PG), glycerin, nicotine, ethanol, acetol, and propylene oxide. The latter, with mass concentrations of 0.4-0.6%, is a possible carcinogen and respiratory irritant. Aerosols generated with vaporizers contained up to 31 compounds, including nicotine, nicotyrine, formaldehyde, acetaldehyde, glycidol, acrolein, acetol, and diacetyl. Glycidol is a probable carcinogen not previously identified in the vapor, and acrolein is a powerful irritant. Emission rates ranged from tens to thousands of nanograms of toxicants per milligram of e-liquid vaporized, and they were significantly higher for a single-coil vs a double-coil vaporizer (by up to an order of magnitude for aldehydes). By increasing the voltage applied to a single-coil device from 3.3 to 4.8 V, the mass of e-liquid consumed doubled from 3.7 to 7.5 mg puff(-1) and the total aldehyde emission rates tripled from 53 to 165 μg puff(-1), with acrolein rates growing by a factor of 10. Aldehyde emissions increased by more than 60% after the device was reused several times, likely due to the buildup of polymerization byproducts that degraded upon heating. These findings suggest that thermal degradation byproducts are formed during vapor generation. Glycidol and acrolein were primarily produced by glycerin degradation. Acetol and 2-propen-1-ol were produced mostly from PG, while other compounds (e.g., formaldehyde) originated from both. Because emissions originate from reaction of the most common e-liquid constituents (solvents), harmful emissions are expected to be ubiquitous when e-cigarette vapor is present.

  20. Endocrine disrupters and human health: could oestrogenic chemicals in body care cosmetics adversely affect breast cancer incidence in women?

    Science.gov (United States)

    Harvey, Philip W; Darbre, Philippa

    2004-01-01

    In the decade that has elapsed since the suggestion that exposure of the foetal/developing male to environmental oestrogens could be the cause of subsequent reproductive and developmental effects in men, there has been little definitive research to provide conclusions to the hypothesis. Issues of exposure and low potency of environmental oestrogens may have reduced concerns. However, the hypothesis that chemicals applied in body care cosmetics (including moisturizers, creams, sprays or lotions applied to axilla or chest or breast areas) may be affecting breast cancer incidence in women presents a different case scenario, not least in the consideration of the exposure issues. The specific cosmetic type is not relevant but the chemical ingredients in the formulations and the application to the skin is important. The most common group of body care cosmetic formulation excipients, namely p-hydroxybenzoic acid esters or parabens, have been shown recently to be oestrogenic in vitro and in vivo and now have been detected in human breast tumour tissue, indicating absorption (route and causal associations have yet to be confirmed). The hypothesis for a link between oestrogenic ingredients in underarm and body care cosmetics and breast cancer is forwarded and reviewed here in terms of: data on exposure to body care cosmetics and parabens, including dermal absorption; paraben oestrogenicity; the role of oestrogen in breast cancer; detection of parabens in breast tumours; recent epidemiology studies of underarm cosmetics use and breast cancer; the toxicology database; the current regulatory status of parabens and regulatory toxicology data uncertainties. Notwithstanding the major public health issue of the causes of the rising incidence of breast cancer in women, this call for further research may provide the first evidence that environmental factors may be adversely affecting human health by endocrine disruption, because exposure to oestrogenic chemicals through application

  1. Variations of the chemical composition and bioactivity of essential oils from leaves and stems of Liquidambar styraciflua (Altingiaceae).

    Science.gov (United States)

    El-Readi, Mahmoud Z; Eid, Hanaa H; Ashour, Mohamed L; Eid, Safaa Y; Labib, Rola M; Sporer, Frank; Wink, Michael

    2013-11-01

    This study aimed to evaluate the variations of the chemical composition and bioactivity of essential oils of Liquidambar styraciflua L. (Altingiaceae) collected in different seasons. The oils were analysed by GLC/FID and GLC/MS. The antioxidant activity was investigated by diphenylpicrylhydrazyl (DPPH) and superoxide anion radical scavenging assays and the deoxyribose degradation assay. Inhibition of both 5-lipoxygenase (5-LOX) and prostaglandin E2 (PGE2) production in hepatic cancer (HepG-2) cells were used to assess the anti-inflammatory activity. The cytotoxic activity was investigated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Altogether, 64 volatile secondary metabolites were identified. The major components of the leaf oil were d-limonene, α-pinene and β-pinene, and of the stem oil were germacrine D, α-cadinol, d-limonene, α-pinene, and β-pinene. Leaf and stem oils collected in spring could reduce DPPH● (IC50 = 3.17 and 2.19 mg/ml) and prevent the degradation of the deoxyribose sugar (IC50 = 17.55 and 14.29 μg/ml). The stem oil exhibited a higher inhibition of both 5-LOX and PGE2 than the leaf oil. The cytotoxic activity of leaf and stem oils was low in cancer cell lines (IC50 = 136.27 and 119.78 μg/ml in cervical cancer (HeLa) cells). Essential oils of L. styraciflua exhibited an interesting anti-inflammatory activity with low cytotoxicity, supporting its traditional use to treat inflammation. © 2013 Royal Pharmaceutical Society.

  2. Survey of naturally and conventionally cured commercial frankfurters, ham, and bacon for physio-chemical characteristics that affect bacterial growth.

    Science.gov (United States)

    Sullivan, Gary A; Jackson-Davis, Armitra L; Schrader, Kohl D; Xi, Yuan; Kulchaiyawat, Charlwit; Sebranek, Joseph G; Dickson, James S

    2012-12-01

    Natural and organic food regulations preclude the use of sodium nitrite/nitrate and other antimicrobials for processed meat products. Consequently, processors have begun to use natural nitrate/nitrite sources, such as celery juice/powder, sea salt, and turbinado sugar, to manufacture natural and organic products with cured meat characteristics but without sodium nitrite. The objective of this study was to compare physio-chemical characteristics that affect Clostridium perfringens and Listeria monocytogenes growth in naturally cured and traditionally cured commercial frankfurters, hams, and bacon. Correlations of specific product characteristics to pathogen growth varied between products and pathogens, though water activity, salt concentration, and product composition (moisture, protein and fat) were common intrinsic factors correlated to pathogen growth across products. Other frequently correlated traits were related to curing reactions such as % cured pigment. Residual nitrite and nitrate were significantly correlated to C. perfringens growth but only for the ham products. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. Chemical characterization of polycyclic aromatic hydrocarbons (PAHs) in 2013 Rayong oil spill-affected coastal areas of Thailand.

    Science.gov (United States)

    Pongpiachan, S; Hattayanone, M; Tipmanee, D; Suttinun, O; Khumsup, C; Kittikoon, I; Hirunyatrakul, P

    2018-02-01

    Among Southeast Asian countries, Thailand has gradually accustomed to extremely prompt urbanization, motorization, and industrialization. Chonburi and Rayong provinces are two provinces involved in "eastern seaboard" industrial zones, which is an emerging economic region that plays a key role in Thailand's economy. The 2013 Rayong oil spill did not only cause damages to the coastal and maritime environment, but also undermine trust in the overall safety system and negatively affect the investor confidence. In this study, 69 coastal soils collected around Koh Samed Island were chemically extracted and analyzed for 15 PAHs by using a Shimadzu GCMS-QP2010 Ultra system comprising a high-speed performance system with ASSP function. In this study, numerous diagnostic binary ratios were applied to identify potential sources of PAHs. Advanced statistical techniques such as hierarchical cluster analysis coupled with principal component analysis were also conducted for further investigations of source identifications. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Using gas flux to estimate biological and chemical sediment oxygen demand in oil sands-affected wetlands

    Energy Technology Data Exchange (ETDEWEB)

    Gardner Costa, J.; Slama, C.; Ciborowski, J. [Windsor Univ., ON (Canada)

    2010-07-01

    The constituents of oil sands process-affected (OSPM) wetlands include high salinity, conductivity and naphthenic acid concentrations. These constituents are expected to strain microbial communities and change methane and carbon dioxide flux rates as well as sediment oxygen consumption compared to fresher, reference wetland sites. Four OSPM and 4 reference wetlands were examined during the summers of 2009 and 2010 to determine if carbon loss in the form of sediment-associated microbial respiration differs between OSPM and reference wetlands. The study showed that OSPM wetlands release about 10 times less methane than reference wetlands. Sediment oxygen demand (SOD) was measured in 2009 and gas flux estimates of carbon dioxide were used to estimate biological sediment oxygen consumption (BSOC). Chemical sediment oxygen demand (CSOD) was estimated by subtracting BSOC from total SOD. SOD rates were found to be two times higher in OSPM wetlands than reference. CSOD was higher than biologically consumed oxygen for both wetland classes. Although microbial activity in OSPM wetlands may be lower, more oxygen is consumed in OSPM than in reference wetlands. The reclamation of boreal wetlands in the Alberta Athabasca region requires carbon accrual. Less microbial activity may promote carbon accumulation within OSPM wetlands. However, the wetland's sediment layer may have less organic input as a result of high chemical oxygen consumption because it limits benthos respiration.

  5. The predictive accuracy of secondary chemical shifts is more affected by protein secondary structure than solvent environment

    Energy Technology Data Exchange (ETDEWEB)

    Tremblay, Marie-Laurence; Banks, Aaron W.; Rainey, Jan K., E-mail: jan.rainey@dal.c [Dalhousie University, Department of Biochemistry and Molecular Biology (Canada)

    2010-04-15

    Biomolecular NMR spectroscopy frequently employs estimates of protein secondary structure using secondary chemical shift ({Delta}{delta}) values, measured as the difference between experimental and random coil chemical shifts (RCCS). Most published random coil data have been determined in aqueous conditions, reasonable for non-membrane proteins, but potentially less relevant for membrane proteins. Two new RCCS sets are presented here, determined in dimethyl sulfoxide (DMSO) and chloroform:methanol:water (4:4:1 by volume) at 298 K. A web-based program, CS-CHEMeleon, has been implemented to determine the accuracy of secondary structure assessment by calculating and comparing {Delta}{delta} values for various RCCS datasets. Using CS-CHEMeleon, {Delta}{delta} predicted versus experimentally determined secondary structures were compared for large datasets of membrane and non-membrane proteins as a function of RCCS dataset, {Delta}{delta} threshold, nucleus, localized parameter averaging and secondary structure type. Optimized {Delta}{delta} thresholds are presented both for published and for the DMSO and chloroform:methanol:water derived RCCS tables. Despite obvious RCCS variations between datasets, prediction of secondary structure was consistently similar. Strikingly, predictive accuracy seems to be most dependent upon the type of secondary structure, with helices being the most accurately predicted by {Delta}{delta} values using five different RCCS tables. We suggest caution when using {Delta}{delta}-based restraints in structure calculations as the underlying dataset may be biased. Comparative assessment of multiple RCCS datasets should be performed, and resulting {Delta}{delta}-based restraints weighted appropriately relative to other experimental restraints.

  6. Research upon the quality assurance of the rolling-mill rolls and the variation boundaries of the chemical composition

    Directory of Open Access Journals (Sweden)

    Kiss, I.

    2008-08-01

    Full Text Available The cast-iron rolls must present higher hardness at the rolling surface and lower in the core and the necks, adequate with mechanical resistance and in the high work temperature. If in the zone of the rolling surface, the hardness is guarantied by the irons structure, through the cementite quantities, the core of rolls must contain graphite, to assure this property. Starting from the lamination equipments aspects, from the form of rolls, of the technological interest zones and the structure, which assures the exploitation property, it was establish, through modeling, to the mathematical description of a direct influences, and in final, through successive determinations, to an optimum. One of the parameters, which are determined the structure of the irons destined for rolls casting, is the chemical composition, which guaranties the exploitation properties of the each roll in the stand of rolling mill. The realization of optimum chemical compositions of the cast-iron can constitute a technical efficient way to assure the exploitation properties, the material from which the rolling mills rolls are manufactured having an important role in this sense. Although the manufacture of rolls is in continuously perfecting, the requirements for superior quality rolls are not yet completely satisfied, in many cases, the absence of quality rolls preventing the realization of quality laminates or the realization of productivities of which rolling mills are capable. This paper presents an analysis of the main alloying elements from chemical composition, the influences upon the mechanical properties of the cast-iron rolls, and presents also some graphical addenda. Using the Matlab calculation and graphical programs we determinate some correlations between the hardness (on the working surface and on necks and the chemical composition. Using the double and triple correlations is really helpful in the foundry practice, as it allows us to determine variation

  7. Drift, selection, or migration? Processes affecting genetic differentiation and variation along a latitudinal gradient in an amphibian.

    Science.gov (United States)

    Cortázar-Chinarro, Maria; Lattenkamp, Ella Z; Meyer-Lucht, Yvonne; Luquet, Emilien; Laurila, Anssi; Höglund, Jacob

    2017-08-14

    Past events like fluctuations in population size and post-glacial colonization processes may influence the relative importance of genetic drift, migration and selection when determining the present day patterns of genetic variation. We disentangle how drift, selection and migration shape neutral and adaptive genetic variation in 12 moor frog populations along a 1700 km latitudinal gradient. We studied genetic differentiation and variation at a MHC exon II locus and a set of 18 microsatellites. Using outlier analyses, we identified the MHC II exon 2 (corresponding to the β-2 domain) locus and one microsatellite locus (RCO8640) to be subject to diversifying selection, while five microsatellite loci showed signals of stabilizing selection among populations. STRUCTURE and DAPC analyses on the neutral microsatellites assigned populations to a northern and a southern cluster, reflecting two different post-glacial colonization routes found in previous studies. Genetic variation overall was lower in the northern cluster. The signature of selection on MHC exon II was weaker in the northern cluster, possibly as a consequence of smaller and more fragmented populations. Our results show that historical demographic processes combined with selection and drift have led to a complex pattern of differentiation along the gradient where some loci are more divergent among populations than predicted from drift expectations due to diversifying selection, while other loci are more uniform among populations due to stabilizing selection. Importantly, both overall and MHC genetic variation are lower at northern latitudes. Due to lower evolutionary potential, the low genetic variation in northern populations may increase the risk of extinction when confronted with emerging pathogens and climate change.

  8. Variations of aerosol size distribution, chemical composition and optical properties from roadside to ambient environment: A case study in Hong Kong, China

    Science.gov (United States)

    Zhang, Qian; Ning, Zhi; Shen, Zhenxing; Li, Guoliang; Zhang, Junke; Lei, Yali; Xu, Hongmei; Sun, Jian; Zhang, Leiming; Westerdahl, Dane; Gali, Nirmal Kumar; Gong, Xuesong

    2017-10-01

    This study investigated the ;roadside-to-ambient; evolution of particle physicochemical and optical properties in typical urban atmospheres of Hong Kong through collection of chemically-resolved PM2.5 data and PM2.5 size distribution at a roadside and an ambient site. Roadside particle size distribution showed typical peaks in the nuclei mode (30-40 nm) while ambient measurements peaked in the Aitken mode (50-70 nm), revealing possible condensation and coagulation growth of freshly emitted particles during aging processes. Much higher levels of anthropogenic chemical components, i.e. nitrate, sulfate, ammonium, organic carbon (OC) and elemental carbon (EC), but lower levels of OC/EC and secondary inorganic aerosols (SIA)/EC ratios appeared in roadside than ambient particles. The high OC/EC and SIA/EC ratios in ambient particles implied high contributions from secondary aerosols. Black carbon (BC), a strong light absorbing material, showed large variations in optical properties when mixed with other inorganic and organic components. Particle-bound polycyclic aromatic hydrocarbons (p-PAHs), an indicator of brown carbon (BrC), showed significant UV-absorbing ability. The average BC and p-PAHs concentrations were 3.8 and 87.6 ng m-3, respectively, at the roadside, but were only 1.5 and 18.1 ng m-3 at the ambient site, suggesting BC and p-PAHs concentrations heavily driven by traffic emissions. In contrast, PM2.5 UV light absorption coefficients (babs-BrC,370nm) at the ambient site (4.2 Mm-1) and at the roadside site (4.1 Mm-1) were similar, emphasizing that particle aging processes enhanced UV light-absorbing properties, a conclusion that was also supported by the finding that the Absorption Ångström coefficient (AAC) value at UV wavelengths (AAC_UV band) at the ambient site were ∼1.7 times higher than that at the roadside. Both aqueous reaction and photochemically produced secondary organic aerosol (SOA) for ambient aerosols contributed to the peak values of babs

  9. Epilepsy-causing sequence variations in SIK1 disrupt synaptic activity response gene expression and affect neuronal morphology.

    Science.gov (United States)

    Pröschel, Christoph; Hansen, Jeanne N; Ali, Adil; Tuttle, Emily; Lacagnina, Michelle; Buscaglia, Georgia; Halterman, Marc W; Paciorkowski, Alex R

    2017-02-01

    SIK1 syndrome is a newly described developmental epilepsy disorder caused by heterozygous mutations in the salt-inducible kinase SIK1. To better understand the pathophysiology of SIK1 syndrome, we studied the effects of SIK1 pathogenic sequence variations in human neurons. Primary human fetal cortical neurons were transfected with a lentiviral vector to overexpress wild-type and mutant SIK1 protein. We evaluated the transcriptional activity of known downstream gene targets in neurons expressing mutant SIK1 compared with wild type. We then assayed neuronal morphology by measuring neurite length, number and branching. Truncating SIK1 sequence variations were associated with abnormal MEF2C transcriptional activity and decreased MEF2C protein levels. Epilepsy-causing SIK1 sequence variations were associated with significantly decreased expression of ARC (activity-regulated cytoskeletal-associated) and other synaptic activity response element genes. Assay of mRNA levels for other MEF2C target genes NR4A1 (Nur77) and NRG1, found significantly, decreased the expression of these genes as well. The missense p.(Pro287Thr) SIK1 sequence variation was associated with abnormal neuronal morphology, with significant decreases in mean neurite length, mean number of neurites and a significant increase in proximal branches compared with wild type. Epilepsy-causing SIK1 sequence variations resulted in abnormalities in the MEF2C-ARC pathway of neuronal development and synapse activity response. This work provides the first insights into the mechanisms of pathogenesis in SIK1 syndrome, and extends the ARX-MEF2C pathway in the pathogenesis of developmental epilepsy.

  10. Assessing Heat-to-Heat Variations Affecting Mechanism Based Modeling of Hydrogen Environment Cracking (HEAC) in High Strength Alloys for Marine Applications: Monel K-500

    Science.gov (United States)

    2016-01-28

    shafts, oil-well tools and instruments, surgical blades and scrapers, springs, valve trim, fasteners, and marine propeller shafts. These Ni-based...34Assessing Heat-to-Heat Variations Affecting Mechanism Based Modeling of Hydrogen Environment Cracking (HEAC) in High Strength Alloys for Marine ...Environment Cracking (HEAC) in High Strength Alloys for Marine Applications: Monel K-500 5a. CONTRACT NUMBER N00014-12-1-0506 5b. GRANT NUMBER N/A 5c

  11. Soil Chemical Properties and Nutrient Uptake of Cocoa as Affected by Application of Different Organic Matters and Phosphate Fertilizers

    Directory of Open Access Journals (Sweden)

    Sugiyanto Sugiyanto

    2008-07-01

    Full Text Available Effort repair of land quality better be done by simultan namely with application of organic matters and inorganic fertilization. The objective of this research is to study the effect of varied organic matters source and phosphate fertilizers on the chemicals soil characteristic and cocoa nutrient uptake. The experiment was laid experimentally in split-plot design and environmentally in randomized complete block design. The main plot was source of P consisted of, control, SP 36 and rock phosphate in dosage of 200 mg P2O5 per kg of air dry soil. Source of organic matter as sub-plot consisted of control (no organic matter, cow dung, cocoa pod husk compost and sugar cane filter cake, each in dosage of 2.5 and 5.0%. Result of this experiment showed application of cow dung, cocoa pod husk compost and sugar cane filter cake increased content of C, N, Ca exchangeable, Fe available, and pH in soil, and SP 36 increased availability of P in soil. Application of sugar cane filter cake increased N, K, Ca, Mg, and SO4 uptake but did not increase Cl uptake, application of cow dung in dosage 5% increased N, K, and Cl uptake and cocoa pod husk compost dosage 5% increased N and K uptake of cocoa. SP 36 increased Mg uptake of cocoa but rock phosphate did not increase it. They were not interaction between organic matters and phosphate fertilizers to nutrient uptake of cocoa. Nutrient soil content as affected by organic matters correlated with nutrient uptake of cocoa.Key words : soil chemical properties, nutrient uptake, cocoa, organic matter, phosphate fertlizers.

  12. Evaluation of significant sources influencing the variation of physico-chemical parameters in Port Blair Bay, South Andaman, India by using multivariate statistics.

    Science.gov (United States)

    Sahu, Biraja Kumar; Begum, Mehmuna; Khadanga, M K; Jha, Dilip Kr; Vinithkumar, N V; Kirubagaran, R

    2013-01-15

    Port Blair is the capital city of Andaman & Nicobar Islands, the union territory of India. More than 50% of the population of these islands lives around Port Blair Bay. Therefore the anthropogenic effects in the bay water were studied for monitoring purpose from seven stations. Physico-chemical parameters of seawater were analyzed in samples collected once in every 3 months for 2 years from seven sampling stations located in Port Blair Bay, South Andaman Island to evaluate the spatial and tidal variation. Cluster analysis and factor analysis were applied to the experimental data in an attempt to understand the sources of variation of physico-chemical parameters. In cluster analysis, the stations Junglighat Bay and Phoenix Bay having high anthropogenic influence formed a separate group. The factors obtained from factor analysis indicated that the parameters responsible for physico-chemical variations are mainly related to land run-off, sewage outfall and tidal flow. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

  13. Does nitrogen fertilization history affects short-term microbial responses and chemical properties of soils submitted to different glyphosate concentrations?

    Science.gov (United States)

    Nivelle, Elodie; Verzeaux, Julien; Chabot, Amélie; Roger, David; Spicher, Fabien; Lacoux, Jérôme; Nava-Saucedo, Jose-Edmundo; Catterou, Manuella; Tétu, Thierry

    2017-01-01

    The use of nitrogen (N) fertilizer and glyphosate-based herbicides is increasing worldwide, with agriculture holding the largest market share. The agronomic and socioeconomic utilities of glyphosate are well established; however, our knowledge of the potential effects of glyphosate applied in the presence or absence of long-term N fertilization on microbial functional activities and the availability of soil nutrients remains limited. Using an ex situ approach with soils that did (N+) or did not (N0) receive synthetic N fertilization for 6 years, we assessed the impact of different rates (no glyphosate, CK; field rate, FR; 100 × field rate, 100FR) of glyphosate application on biological and chemical parameters. We observed that, after immediate application (1 day), the highest dose of glyphosate (100FR) negatively affected the alkaline phosphatase (AlP) activity in soils without N fertilization history and decreased the cation exchange capacity (CEC) in N0 compared to CK and FR treatments with N+. Conversely, the 100FR application increased nitrate (NO3-) and available phosphorus (PO43-) regardless of N fertilization history. Then, after 8 and 15 days, the N+\\100FR and N+\\FR treatments exhibited the lowest values for dehydrogenase (DH) and AlP activities, respectively, while urease (URE) activity was mainly affected by N fertilization. After 15 days and irrespective of N fertilization history, the FR glyphosate application negatively affected the degradation of carbon substrates by microbial communities (expressed as the average well color development, AWCD). By contrast, the 100FR treatment positively affected AWCD, increasing PO43- by 5 and 16% and NO3- by 126 and 119% in the N+ and N0 treatments, respectively. In addition, the 100FR treatment resulted in an increase in the average net nitrification rate. Principal component analysis revealed that the 100FR glyphosate treatment selected microbial communities that were able to metabolize amine substrates

  14. Does nitrogen fertilization history affects short-term microbial responses and chemical properties of soils submitted to different glyphosate concentrations?

    Directory of Open Access Journals (Sweden)

    Elodie Nivelle

    Full Text Available The use of nitrogen (N fertilizer and glyphosate-based herbicides is increasing worldwide, with agriculture holding the largest market share. The agronomic and socioeconomic utilities of glyphosate are well established; however, our knowledge of the potential effects of glyphosate applied in the presence or absence of long-term N fertilization on microbial functional activities and the availability of soil nutrients remains limited. Using an ex situ approach with soils that did (N+ or did not (N0 receive synthetic N fertilization for 6 years, we assessed the impact of different rates (no glyphosate, CK; field rate, FR; 100 × field rate, 100FR of glyphosate application on biological and chemical parameters. We observed that, after immediate application (1 day, the highest dose of glyphosate (100FR negatively affected the alkaline phosphatase (AlP activity in soils without N fertilization history and decreased the cation exchange capacity (CEC in N0 compared to CK and FR treatments with N+. Conversely, the 100FR application increased nitrate (NO3- and available phosphorus (PO43- regardless of N fertilization history. Then, after 8 and 15 days, the N+\\100FR and N+\\FR treatments exhibited the lowest values for dehydrogenase (DH and AlP activities, respectively, while urease (URE activity was mainly affected by N fertilization. After 15 days and irrespective of N fertilization history, the FR glyphosate application negatively affected the degradation of carbon substrates by microbial communities (expressed as the average well color development, AWCD. By contrast, the 100FR treatment positively affected AWCD, increasing PO43- by 5 and 16% and NO3- by 126 and 119% in the N+ and N0 treatments, respectively. In addition, the 100FR treatment resulted in an increase in the average net nitrification rate. Principal component analysis revealed that the 100FR glyphosate treatment selected microbial communities that were able to metabolize amine substrates

  15. Small-area variation in health care affecting the choice of cesarean delivery: the case of a Colombian health insurer

    OpenAIRE

    Vecino Ortiz, Andrés Ignacio; Bardey, David; Castaño Yepes, Ramón Abel

    2009-01-01

    In the midst of health care reform, Colombia has succeeded in increasing health insurance coverage and the quality of health care. In spite of this, efficiency continues to be a matter of concern, and small-area variations in health care are one of the plausible causes of such inefficiencies. In order to understand this issue, we use individual data of all births from a Contributory-Regimen insurer in Colombia. We perform two different specifications of a multilevel logistic regression model....

  16. Gelification of Victorian Tertiary soft brown coal wood. II. Changes in chemical structure associated with variation in the degree of gelification

    Energy Technology Data Exchange (ETDEWEB)

    Russell, N.J.; Barron, P.F.

    1984-09-01

    The gross chemical structures of xylites and gelified soft brown coal woods, Latrobe Valley, Victoria, Australia, as determined by solid state nuclear magnetic resonance spectroscopy, are compared with those of present-day wood-derived materials prepared from an angiosperm, Eucalyptus regnans, and a gymnosperm (conifer), Pinus radiata. Also examined are the changes in the gross chemical structures of soft brown coal woods with increase in their degree of gelification and the relationship between these changes and variations in their chemical composition and microscopic appearance. The Victorian xylites exhibit greater affinities with the present-day gymnosperm than the present-day angiosperm. The progressive removal of cellulose with increasing degree of gelification can be equated with an increase in huminite reflectance, elimination of humotelinite autofluoresence and changes in the relative proportions of the humotelinite submacerals. The lignin structure of xylite is also modified during the gelification process, including the progressive loss of methoxyl groups and evidence of minor oxidation.

  17. Chemical properties of lipids strongly affect the kinetics of the membrane-induced aggregation of α-synuclein.

    Science.gov (United States)

    Galvagnion, Céline; Brown, James W P; Ouberai, Myriam M; Flagmeier, Patrick; Vendruscolo, Michele; Buell, Alexander K; Sparr, Emma; Dobson, Christopher M

    2016-06-28

    Intracellular α-synuclein deposits, known as Lewy bodies, have been linked to a range of neurodegenerative disorders, including Parkinson's disease. α-Synuclein binds to synthetic and biological lipids, and this interaction has been shown to play a crucial role for both α-synuclein's native function, including synaptic plasticity, and the initiation of its aggregation. Here, we describe the interplay between the lipid properties and the lipid binding and aggregation propensity of α-synuclein. In particular, we have observed that the binding of α-synuclein to model membranes is much stronger when the latter is in the fluid rather than the gel phase, and that this binding induces a segregation of the lipids into protein-poor and protein-rich populations. In addition, α-synuclein was found to aggregate at detectable rates only when interacting with membranes composed of the most soluble lipids investigated here. Overall, our results show that the chemical properties of lipids determine whether or not the lipids can trigger the aggregation of α-synuclein, thus affecting the balance between functional and aberrant behavior of the protein.

  18. Important chemical and physical traits and variation in these traits in 'tombul' hazelnut cultivar at different elevations

    Directory of Open Access Journals (Sweden)

    Zeki Bostan, S.

    2003-09-01

    Full Text Available This study was conducted on ‘Tombul’ hazelnut growing at four elevations (0-50 m, 100-150 m, 200-250 m and 300-350 m in Persembe (Ordu/ Northern Turkey province in 1999 and 2000 years. Sixteen traits (oil, protein and ash contents as chemical; nut weight, nut size, shell thickness, kernel weight, kernel size, percent kernel, internal cavity, shriveled kernels, good kernels as physical; pH, organic matter, phosphorus and potassium in soil were examined at each elevation. Interrelationships among important soil, nut and kernel characteristics were examined. There were significant correlation and interrelationships among the traits. The correlation between oil-nut size, oil- protein positively; protein-kernel size, protein- shriveled kernel negatively; organic matter- shell thickness, organic matter-good kernel negatively; pH- shell thickness, pH-good kernel negatively; good kernel-shell thickness positively; shriveled kernel-kernel weight, shriveled kernel-percent kernel negatively; internal cavity-nut weight positively and internal cavity-nut size negatively; percent kernel-kernel weight, percent kernel-kernel size positively; kernel size-kernel weight positively, and kernel weight-nut weight positively were significant. Significant differences among elevations were observed for shell thickness, ash content in kernel, and pH value in soil. The highest coefficients of variation were observed for phosphorus, shriveled kernels, potassium, internal cavity and organic matter, respectivelyEste estudio ha sido realizado en la avellana ’Tombul’ que crece en cuatro elevaciones (0-50 m, 100-150 m, 200-250 m y 300- 350 m en la provincia de Persembe (Ordu/ Norte de Turquía en los años 1999 y 2000. Dieciséis rasgos (contenido en aceite, proteína y ceniza como características químicas; peso, tamaño y grosor de cáscara, peso, tamaño y porcentaje del grano, cavidad interna, granos arrugados y granos buenos como características f

  19. Stronger Association Between Valence- and Arousal Ratings of Affective Pictures with Older Age: Evidence for Variation Across Emotion Categories

    DEFF Research Database (Denmark)

    Mikkelsen, Mai Bjørnskov; Mehlsen, Mimi Yung; Lyby, Marlene Skovgaard

    A sample of older and younger adults rated affective pictures according to valence, arousal and emotion category (happiness, sadness and disgust). Results indicate that older age is associated with a stronger linear association between ratings of arousal and valence. Further, the strength...

  20. Local variations in {sup 14}C - How is bomb-pulse dating of human tissues and cells affected?

    Energy Technology Data Exchange (ETDEWEB)

    Stenstroem, Kristina, E-mail: Kristina.Stenstrom@nuclear.lu.s [Lund University, Department of Physics, Division of Nuclear Physics, Box 118, SE-221 00 Lund (Sweden); Skog, Goeran [Lund University, GeoBiosphere Science Centre, Geocentrum II, Soelvegatan 12, SE-223 672 Lund (Sweden); Nilsson, Carl Magnus [Lund University, Department of Physics, Division of Nuclear Physics, Box 118, SE-221 00 Lund (Sweden); Lund University, Department of Medical Radiation Physics, Malmoe University Hospital, SE-205 02 Malmoe (Sweden); Hellborg, Ragnar [Lund University, Department of Physics, Division of Nuclear Physics, Box 118, SE-221 00 Lund (Sweden); Svegborn, Sigrid Leide [Lund University, Department of Medical Radiation Physics, Malmoe University Hospital, SE-205 02 Malmoe (Sweden); Georgiadou, Elisavet [Lund University, Department of Physics, Division of Nuclear Physics, Box 118, SE-221 00 Lund (Sweden); Mattsson, Soeren [Lund University, Department of Medical Radiation Physics, Malmoe University Hospital, SE-205 02 Malmoe (Sweden)

    2010-04-15

    Atmospheric nuclear weapons testing in the late 1950s and early 1960s almost doubled the amount of {sup 14}C in the atmosphere. The resulting {sup 14}C 'bomb-pulse' has been shown to provide useful age information in e.g. forensic and environmental sciences, biology and the geosciences. The technique is also currently being used for retrospective cell dating in man, in order to provide insight into the rate of formation of new cells in the human body. Bomb-pulse dating relies on precise measurements of the declining {sup 14}C concentration in atmospheric CO{sub 2} collected at clean-air sites. However, it is not always recognized that the calculations can be complicated in some cases by significant local variations in the specific activity of {sup 14}C in carbon in the air and foodstuff. This paper presents investigations of local {sup 14}C variations in the vicinities of nuclear installations and laboratories using {sup 14}C. Levels of {sup 14}C in workers using this radioisotope are also discussed.

  1. Local variations in 14C - How is bomb-pulse dating of human tissues and cells affected?

    Science.gov (United States)

    Stenström, Kristina; Skog, Göran; Nilsson, Carl Magnus; Hellborg, Ragnar; Svegborn, Sigrid Leide; Georgiadou, Elisavet; Mattsson, Sören

    2010-04-01

    Atmospheric nuclear weapons testing in the late 1950s and early 1960s almost doubled the amount of 14C in the atmosphere. The resulting 14C "bomb-pulse" has been shown to provide useful age information in e.g. forensic and environmental sciences, biology and the geosciences. The technique is also currently being used for retrospective cell dating in man, in order to provide insight into the rate of formation of new cells in the human body. Bomb-pulse dating relies on precise measurements of the declining 14C concentration in atmospheric CO 2 collected at clean-air sites. However, it is not always recognized that the calculations can be complicated in some cases by significant local variations in the specific activity of 14C in carbon in the air and foodstuff. This paper presents investigations of local 14C variations in the vicinities of nuclear installations and laboratories using 14C. Levels of 14C in workers using this radioisotope are also discussed.

  2. Does inter-plant variation in sprouting time affect the growth/reproduction trade-off and herbivory in a tropical tree species?

    Directory of Open Access Journals (Sweden)

    Marcilio Fagundes

    Full Text Available ABSTRACT The timing of phenological events varies within and among populations, affecting the performance of individual plants differently. We evaluated the effects of relative variation in sprouting time on the display of reproductive events, vegetative growth and herbivory in Copaifera langsdorffii (Fabaceae. A total of 93 trees of C. langsdorffii was monitored daily to determine their sprouting time. We collected ten terminal branches of each plant to evaluate vegetative growth, production of defense compounds and insect herbivore damage. The sprouting time for the studied population lasted 67 days. Variation in sprouting time did not affect the probability of plants to enter the reproductive stage. Plants that entered the reproductive stage showed greater vegetative biomass. Variation in sprouting time had a negative relationship with branch growth and a positive relationship with the number of leaflets. Leaf phenol concentration did not vary in relation to sprouting time or plant phenology, but herbivory was higher in plants that sprouted later. The relationships among plant sprouting time, vegetative development and display of reproductive stage in C. langsdorffii are discussed. The results of this study also suggest that early sprouting prior to the rainy season is a strategy used by C. langsdorffii to escape herbivores attacks.

  3. Performance, carcass characteristics and chemical composition of beef affected by lupine seed, rapeseed meal and soybean meal.

    Science.gov (United States)

    Sami, A S; Schuster, M; Schwarz, F J

    2010-08-01

    To test the effects of different protein sources and levels on performance, carcass characteristics and beef chemical composition, concentrates with three protein sources [Lupine seed (L), Rapeseed meal (R) and Soybean meal (S)] and two protein levels ['normal protein' (NP) or 'high protein' (HP)] were fed to 36 Simmental calves. Calves initially weighed 276 +/- 3.9 kg and averaged 6 months of age and were randomly allocated to the six treatments. Maize silage was offered ad libitum and supplemented with increasing amounts of concentrates (wheat, maize grain, protein sources, vitamin-mineral mix). Normal protein and HP diets were formulated to contain 12.4% and 14.0% crude protein (CP) dry matter (DM) respectively. At the end of the fattening period of 278 days, the final live weight averaged 683 +/- 14.7 kg. Neither level of protein nor its interaction with protein sources had any effects on most of the traits studied. Feeding the R diet significantly increased final weight, average daily gain (ADG), DM intake and CP intake in relation to the L diet; no differences were observed between the L and S diets for these measures. No differences were observed between the R and S groups in final weight or ADG, but the calves fed the R diet consumed more DM and CP than the calves fed the S diet. Bulls fed R diet had higher carcass weight and dressing percentage than the L groups, and no significant differences were detected between the S and L groups. Chemical composition of the Musculus longissimus dorsi was not significantly affected by source of protein. Also, the major saturated fatty acid (SFA) (C16:0 and C18:0) did not significantly differ among the three treatments. Samples from R group had significantly higher proportions of C16:1 t9, C18:1 c11, C18:2 c9 t11, C18:3 c9, 12, 15 and SigmaC18:1 t fatty acids in relation to L and S groups. Although polyunsaturated fatty acid/SFA ratio was similar for the three dietary groups, n-6/n-3 ratio and Sigman-3 fatty acids

  4. The erratic mitochondrial clock: variations of mutation rate, not population size, affect mtDNA diversity across birds and mammals

    Directory of Open Access Journals (Sweden)

    Galtier Nicolas

    2009-03-01

    Full Text Available Abstract Background During the last ten years, major advances have been made in characterizing and understanding the evolution of mitochondrial DNA, the most popular marker of molecular biodiversity. Several important results were recently reported using mammals as model organisms, including (i the absence of relationship between mitochondrial DNA diversity and life-history or ecological variables, (ii the absence of prominent adaptive selection, contrary to what was found in invertebrates, and (iii the unexpectedly large variation in neutral substitution rate among lineages, revealing a possible link with species maximal longevity. We propose to challenge these results thanks to the bird/mammal comparison. Direct estimates of population size are available in birds, and this group presents striking life-history trait differences with mammals (higher mass-specific metabolic rate and longevity. These properties make birds the ideal model to directly test for population size effects, and to discriminate between competing hypotheses about the causes of substitution rate variation. Results A phylogenetic analysis of cytochrome b third-codon position confirms that the mitochondrial DNA mutation rate is quite variable in birds, passerines being the fastest evolving order. On average, mitochondrial DNA evolves slower in birds than in mammals of similar body size. This result is in agreement with the longevity hypothesis, and contradicts the hypothesis of a metabolic rate-dependent mutation rate. Birds show no footprint of adaptive selection on cytochrome b evolutionary patterns, but no link between direct estimates of population size and cytochrome b diversity. The mutation rate is the best predictor we have of within-species mitochondrial diversity in birds. It partly explains the differences in mitochondrial DNA diversity patterns observed between mammals and birds, previously interpreted as reflecting Hill-Robertson interferences with the W

  5. Genetic Variations of TAP1 Gene Exon 3 Affects Gene Expression and Escherichia coli F18 Resistance in Piglets

    Directory of Open Access Journals (Sweden)

    Qiaohui Zhao

    2014-06-01

    Full Text Available Firstly, our research group identified Sutai pigs’ phenotypes that exhibited extreme resistance and susceptibility to the Escherichia coli F18 respectively, and then eight ETEC (Enterotoxigenic Escherichia coli F18-resistant piglets and eight ETEC F18-sensitive piglets were selected. Then, the TAP1 (Transporter associated with antigen processing mRNA relative expression levels were analyzed in 11 tissues of the resistant and susceptible phenotypes. Simultaneously, we detected the genetic variations in exon 3 of the TAP1 gene and evaluated the TAP1 mRNA expression levels among the different genotype pigs to study the effects of the genetic variation on gene expression, and the E. coli F18 resistance. The results revealed higher expression levels in the resistant genotypes than that in the susceptible genotypes in 11 tissues, with significant differences in the spleen, lymph node, lung, thymus, duodenum and jejunum. Furthermore, a G729A mutation was identified in the TAP1 gene exon 3, and this mutation deviates from Hardy-Weinberg equilibrium (p < 0.01. The TAP1 mRNA levels in GG genotype were significantly higher than that in the other two genotypes, with significant differences in the liver, lung, kidney, thymus, lymph node, duodenum and jejunum tissues. We speculated that high expression of the TAP1 gene might confer resistance against the E. coli F18, the G729A mutation had a significant effect on the mRNA expression, and individuals with the GG genotype possessed a stronger ability to resist the E. coli F18 infection.

  6. Microclimate affects soil chemical and mineralogical properties of cold-alpine soils of the Altai Mountains (Russia)

    Science.gov (United States)

    Egli, Markus; Lessovaia, Sofia; Chistyakov, Kirill; Inozemzev, Svyatoslav

    2013-04-01

    Precipitation and temperature particularly influence soil properties by affecting the type and rates of chemical, biological, and physical processes. To a great extent, element leaching and weathering rates are governed by these processes. Vegetation growth and decomposition, that depend on temperature and the other environmental factors, influence weathering reactions through the production of acidity and organic ligands that may promote chemical weathering and subsequent elemental leaching. The present work focuses on cold-alpine soils of the Altai Mountains (Siberia, Russia). The investigated field site (2380 m asl) is characterised by cold winters (with absolute minimum temperatures of -50°C; a mean temperature in January is -21°C) and cool summers (+8°C mean temperature in July). The mean annual temperature is -5.4°C. Annual precipitations are relatively low (500 mm with 20% of precipitation in July). Permafrost is widespread and occurs sometimes at a depth of 30 to 50 cm. Several studies have shown the influence of slope aspect and the resulting microclimate on soil weathering and development. There is however no unanimous agreement whether weathering is more intense on north- or south-facing slopes and whether small differences in thermal conditions may lead to detectable differences. Higher temperatures do not necessarily lead to higher weathering rates in cold alpine regions as shown by previous investigations in the European Alps. Water fluxes through the soils seemed to be more important. We consequently investigated soils in the cold-alpine environment of the Central Altai Mountains on a very small area close to a local glacier tongue. Half of the investigated soil profiles were south-facing (5) and the other half north-facing (5). The soils have the same parent material (mica-rich till), altitude, topography, and soil age. The vegetation is alpine grassland that is partially intersected with some juniper and mosses, which portion in the soil

  7. Cells and the environment. How do chemical pollutants affect cells. Zelle und Umwelt. Wie wirken sich Umweltgifte auf Zellen aus

    Energy Technology Data Exchange (ETDEWEB)

    Braunbeck, T.; Storch, V. (Heidelberg Univ. (Germany, F.R.). Zoologisches Inst.)

    1989-08-01

    It is possible by means of ultrastructural techniques to prove the harmful effect of chemicals on animal organisms through changes in monitoring organs such as the liver of vertebrates very early and with great sensitivity. The reaction of the fish liver to chemicals in dependence of other factors (fish species, sex) is demonstrated by the example of various model chemicals as well as two pesticides. (orig.).

  8. Variation in the Phosphoinositide 3-Kinase Gamma Gene Affects Plasma HDL-Cholesterol without Modification of Metabolic or Inflammatory Markers.

    Directory of Open Access Journals (Sweden)

    Martin Kächele

    Full Text Available Phosphoinositide 3-kinase γ (PI3Kγ is a G-protein-coupled receptor-activated lipid kinase mainly expressed in leukocytes and cells of the cardiovascular system. PI3Kγ plays an important signaling role in inflammatory processes. Since subclinical inflammation is a hallmark of atherosclerosis, obesity-related insulin resistance, and pancreatic β-cell failure, we asked whether common genetic variation in the PI3Kγ gene (PIK3CG contributes to body fat content/distribution, serum adipokine/cytokine concentrations, alterations in plasma lipid profiles, insulin sensitivity, insulin release, and glucose homeostasis.Using a tagging single nucleotide polymorphism (SNP approach, we analyzed genotype-phenotype associations in 2,068 German subjects genotyped for 10 PIK3CG SNPs and characterized by oral glucose tolerance tests. In subgroups, data from hyperinsulinaemic-euglycaemic clamps, magnetic resonance spectroscopy of the liver, whole-body magnetic resonance imaging, and intravenous glucose tolerance tests were available, and peripheral blood mononuclear cells (PBMCs were used for gene expression analysis.After appropriate adjustment, none of the PIK3CG tagging SNPs was significantly associated with body fat content/distribution, adipokine/cytokine concentrations, insulin sensitivity, insulin secretion, or blood glucose concentrations (p>0.0127, all; Bonferroni-corrected α-level: 0.0051. However, six non-linked SNPs displayed at least nominal associations with plasma HDL-cholesterol concentrations, two of them (rs4288294 and rs116697954 reaching the level of study-wide significance (p = 0.0003 and p = 0.0004, respectively. More precisely, rs4288294 and rs116697954 influenced HDL2-, but not HDL3-, cholesterol. With respect to the SNPs' in vivo functionality, rs4288294 was significantly associated with PIK3CG mRNA expression in PBMCs.We could demonstrate that common genetic variation in the PIK3CG locus, possibly via altered PIK3CG gene expression

  9. Daytime variation in ambient temperature affects skin temperatures and blood pressure: Ambulatory winter/summer comparison in healthy young women.

    Science.gov (United States)

    Martinez-Nicolas, Antonio; Meyer, Martin; Hunkler, Stefan; Madrid, Juan Antonio; Rol, Maria Angeles; Meyer, Andrea H; Schötzau, Andy; Orgül, Selim; Kräuchi, Kurt

    2015-10-01

    It is widely accepted that cold exposure increases peripheral vascular resistance and arterial blood pressure (BP) and, hence, increases cardiovascular risk primarily in the elderly. However, there is a lack of concomitantly longitudinal recordings at personal level of environmental temperature (PET) and cardiophysiological variables together with skin temperatures (STs, the “interface-variable” between the body core and ambient temperature). To investigate the intra-individual temporal relationships between PET, STs and BP 60 healthy young women (52 completed the entire study) were prospectively studied in a winter/summer design for 26 h under real life conditions. The main hypothesis was tested whether distal ST (Tdist)mediates the effect of PET-changes on mean arterial BP (MAP). Diurnal profiles of cardiophysiological variables (including BP), STs and PET were ambulatory recorded. Daytime variations between 0930 and 2030 h were analyzed in detail by intra-individual longitudinal path analysis. Additionally, time segments before, during and after outdoor exposure were separately analyzed. In both seasons short-term variations in PET were positively associated with short-term changes in Tdist (not proximal ST, Tprox) and negatively with those in MAP. However, long-term seasonal differences in daytime mean levels were observed in STs but not in BP leading to non-significant inter-individual correlation between STs and BP. Additionally, higher individual body mass index (BMI) was significantly associated with lower daytime mean levels of Tprox and higher MAP suggesting Tprox as potential mediator variable for the association of BMI with MAP. In healthy young women the thermoregulatory and BP-regulatory systems are closely linked with respect to short-term, but not long-term changes in PET. One hypothetical explanation could serve recent findings that thermogenesis in brown adipose tissue is activated in a cool environment, which could be responsible for the

  10. [Book review] Epiphytic Lichen Diversity and its Dependence on Chemical Site Factors in Differently Elevated Dieback-affected Spruce Stands of the Harz Mountains, by Volker Hesse

    Science.gov (United States)

    Bennett, J.P.

    2002-01-01

    Review of: Epiphytic lichen diversity and its dependence on chemical site factors in differently elevated dieback-affected spruce stands of the Harz Mountains. (Dissertationes Botanicae, Band 354). Volker Hesse. 2002. 191 pages, 66 figures, 49 tables, 23x14cm, 390 g. ISBN 978-3-443-64266-2.

  11. Initial substrate moisture content and storage temperature affects chemical properties of bagged substrates containing controlled release fertilizer at two different temperatures

    Science.gov (United States)

    Bagged potting mixes can be stored for weeks or months before being used by consumers. Some bagged potting mixes are amended with controlled release fertilizers (CRF). The objective of this research was to observe how initial substrate moisture content and storage temperature affect the chemical p...

  12. Genetic variation in Micro-RNA genes of host genome affects clinical manifestation of symptomatic Human Cytomegalovirus infection.

    Science.gov (United States)

    Misra, Maneesh Kumar; Mishra, Aditi; Pandey, Shashi Kant; Kapoor, Rakesh; Sharma, Raj Kumar; Agrawal, Suraksha

    2015-10-01

    Micro-RNAs are implicated in various physiological and pathologic processes. In this study, we tested whether Micro-RNA gene variants of host-genome affect clinical manifestation of symptomatic HCMV infection. HCMV infection was detected by fluorescent PCR and immuno-histochemistry. The detection of genetic variants of four studied Micro-RNA tag-SNPs was done through PCR-RFLP assay and validated with DNA sequencing. We observed an increased risk ranged from 3-folds to 5-folds among symptomatic HCMV cases for mutant genotype of rs2910164 (crude OR=3.11, p=0.009 and adjusted OR=3.25, p=0.007), rs11614913 (crude OR=3.20, p=0.006 and adjusted OR=3.48, p=0.004) and rs3746444 (crude OR=4.91, p=0.002 and adjusted OR=5.28, p=0.002) tag-SNPs. Interestingly, all the tag-SNPs that were significant after multiple comparisons at a FDR of 5% in symptomatic HCMV cases remained significant even after bootstrap analysis, providing internal validation to these results. Multifactor Dimensionality Reduction (MDR) analysis revealed 5-folds increased risk for symptomatic HCMV cases under the four-factor model (rs2910164, rs2292832, rs11614913 and rs3746444). These results suggest that Micro-RNA gene variants of host-genome may affect clinical manifestation of symptomatic HCMV infection. Copyright © 2015 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

  13. Geometrical variations in white and gray matter affect the biomechanics of spinal cord injuries more than the arachnoid space

    Directory of Open Access Journals (Sweden)

    Léo Fradet

    2016-08-01

    Full Text Available Traumatic spinal cord contusions lead to loss of quality of life, but their pathomechanisms are not fully understood. Previous studies have underlined the contribution of the cerebrospinal fluid in spinal cord protection. However, it remains unclear how important the contribution of the cerebrospinal fluid is relative to other factors such as the white/gray matter ratio. A finite element model of the spinal cord and surrounding morphologic features was used to investigate the spinal cord contusion mechanisms, considering subarachnoid space and white/gray matter ratio. Two vertebral segments (T6 and L1 were impacted transversely at 4.5 m s−1, which demonstrated three major results: While the presence of cerebrospinal fluid plays a significant contributory role in spinal cord protection (compression percentage decreased by up to 19%, the arachnoid space variation along the spine appears to have a limited (3% compression decrease impact. Differences in the white and gray matter geometries from lumbar to thoracic spine levels decrease spinal cord compression by up to 14% at the thoracic level. Stress distribution in the sagittal spinal cord section was consistent with central cord syndrome, and local stress concentration on the anterior part of the spinal cord being highly reduced by the presence of cerebrospinal fluid. The use of a refined spinal cord finite element method showed that all the geometrical parameters are involved in the spinal cord contusion mechanisms. Hence, spinal cord injury criteria must be considered at each vertebral level.

  14. Investigation of primary factors affecting the variation of modeled oak pollen concentrations: A case study for Southeast Texas in 2010

    Science.gov (United States)

    Jeon, Wonbae; Choi, Yunsoo; Roy, Anirban; Pan, Shuai; Price, Daniel; Hwang, Mi-Kyoung; Kim, Kyu Rang; Oh, Inbo

    2017-12-01

    Oak pollen concentrations over the Houston-Galveston-Brazoria (HGB) area in southeastern Texas were modeled and evaluated against in-situ data. We modified the Community Multi-scale Air Quality (CMAQ) model to include oak pollen emission, dispersion, and deposition. The Oak Pollen Emission Model (OPEM) calculated gridded oak pollen emissions, which are based on a parameterized equation considering a plant-specific factor (C e ), surface characteristics, and meteorology. The simulation period was chosen to be February 21 to April 30 in the spring of 2010, when the observed monthly mean oak pollen concentrations were the highest in six years (2009-2014). The results indicated C e and meteorology played an important role in the calculation of oak pollen emissions. While C e was critical in determining the magnitude of oak pollen emissions, meteorology determined their variability. In particular, the contribution of the meteorology to the variation in oak pollen emissions increased with the oak pollen emission rate. The evaluation results using in-situ surface data revealed that the model underestimated pollen concentrations and was unable to accurately reproduce the peak pollen episodes. The model error was likely due to uncertainty in climatology-based C e used for the estimation of oak pollen emissions and inaccuracy in the wind fields from the Weather Research and Forecast (WRF) model.

  15. Does diurnal variation affect the first trimester fetal aneuploidy screening test biochemical parameters of fetuses with normal nuchal translucency?

    Science.gov (United States)

    Karsli, Mehmet Fatih; Cakmak, Bulent; Seckin, Kerem Doga; Akkas Yilmaz, Elif; Akgul, Gurcan; Togrul, Cihan; Kucukozkan, Tuncay

    2016-01-01

    The purpose of this study was to investigate the effect of diurnal variation on biochemical results of first trimester aneuploidy screening test. A total of 2725 singleton pregnant female, who had normal fetal nuchal translucency (NT) thickness, were included in the study during this period. Individuals were divided into two groups according to the sampling time (morning group: 09:00-11:00 am and afternoon group: 02:00-04:00 pm). Hormonal parameters (free-beta human chorionic gonadotropin [free β-hCG] and pregnancy-associated plasma protein-A [PAPP-A] multiples of median [MoM] levels) of first trimester (11(+0)-13(+6) weeks) combined aneuploidy screening test were compared between morning and afternoon groups. PAPP-A MoM levels were significantly lower in the afternoon group when compared to the morning group (p = 0.001), whereas free β-hCG MoM levels were similar in the both groups (p = 0.392). Rate of high risk for Down syndrome (Combine risk >1/300) and amniocentesis ratio were found higher in the afternoon group than morning group, but there were no difference between groups for the number of fetuses with Down syndrome. Receiving the venous blood sample for first trimester aneuploidy screening test in the afternoon causes low PAPP-A MoM levels.

  16. How hearing about harmful chemicals affects smokers' interest in dual use of cigarettes and e-cigarettes.

    Science.gov (United States)

    Pepper, Jessica K; Byron, M Justin; Ribisl, Kurt M; Brewer, Noel T

    2017-03-01

    Substantial harm could result from concurrent cigarette and e-cigarette use (i.e., dual use) were it to undermine smoking cessation. Perceptions of chemical exposure and resulting harms may influence dual use. We conducted a probability-based phone survey of 1164 U.S. adult cigarette smokers in 2014-2015 and analyzed results in 2016. In a between-subjects experiment, smokers heard a hypothetical scenario in which cigarettes and e-cigarettes had the same amount of harmful chemicals or cigarettes had more chemicals than e-cigarettes (10× more, 100× more, or chemicals were present only in cigarettes). Smokers indicated how the scenario would change their interest in dual use and perceived health harms. Few smokers (7%) who heard that the products have the same amount of chemicals were interested in initiating or increasing dual use. However, more smokers were interested when told that cigarettes have 10× more chemicals than e-cigarettes (31%), 100× more chemicals than e-cigarettes (32%), or chemicals were present only in cigarettes (43%) (all pe-cigarettes (79% vs. 41%, OR=5.41, 95% CI=4.08-7.17). These harm perceptions partially explained the relationship between chemical scenario and dual use interest. Smokers associated higher chemical amounts in cigarettes versus e-cigarettes with greater health harms from cigarettes and thus expressed increased interest in dual use. The findings suggest that disclosing amounts of chemicals in cigarette smoke and e-cigarette aerosol could unintentionally encourage dual use. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Inter-laboratory variation in the chemical analysis of acidic forest soil reference samples from eastern North America

    Science.gov (United States)

    D.S. Ross; S.W. Bailey; R.D. Briggs; J. Curry; I.J. Fernandez; G. Fredriksen; C.L. Goodale; P.W. Hazlett; P.R. Heine; C.E. Johnson; J.T. Larson; G.B. Lawrence; R.K. Kolka; R. Ouimet; D. Pare; D. deB. Richter; C.D. Schirmer; R.A. Warby

    2015-01-01

    Long-term forest soil monitoring and research often requires a comparison of laboratory data generated at different times and in different laboratories. Quantifying the uncertainty associated with these analyses is necessary to assess temporal changes in soil properties. Forest soil chemical properties, and methods to measure these properties, often differ from...

  18. The use of microbial and chemical analyses to characterize the variations in fouling profile of seawater reverse osmosis (SWRO) membrane

    KAUST Repository

    Manes, Carmem Lara De O

    2013-01-01

    Biofouling of reverse osmosis (RO) membranes is one of the most common problems in desalinations plants reducing the efficiency of the water production process. The characterization of bacterial community composition from fouling layers as well as detailed analysis of surrounding chemical environment might reveal process specific bacterial groups/species that are involved in RO biofouling. In this study, advanced organics analytic methods (elemental analysis, FTIR, and ICP-OES) were combined with high-throughput 16S rRNA (pyro) sequencing to assess in parallel, the chemical properties and the active microbial community composition of SWRO membranes from a pilot desalination plant (MFT, Tarragona) in February 2011 and July 2011. Prefiltered ultrafiltration. waters fed SWRO membranes during third and fifth month of operation, respectively. SWRO samples were taken from three modules at different positions (first, fourth, and sixth) in order to investigate the spatial changes in fouling layers\\' chemical and microbiological composition. The overall assessment of chemical parameters revealed that fouling layers were mainly composed by bio and organic material (proteins and lipids). Ca and Fe were found to be the most abundant elements having an increasing concentration gradient according to the module position. Bacterial community composition of SWRO membranes is mostly represented by the Gammaproteobacteria class with interesting differences in genera/species spatial and temporal distribution. This preliminary result suggests that pretreatments and/or operational conditions might have selected different bacterial groups more adapted to colonize SWRO membranes. © 2013 Desalination Publications.

  19. A Case Study on Uruk Sulcus, Ganymede: How Variations in Fault Strike and Stress Distribution can Affect Shear Failure

    Science.gov (United States)

    Cameron, M. E.; Smith-Konter, B. R.; Burkhard, L. M.; Collins, G. C.; Pappalardo, R. T.

    2016-12-01

    Ganymede's fractured surface reveals many morphologically distinct regions of inferred distributed shear and strike-slip faulting that may be important to the structural development of its surface. To better understand the role of strike-slip tectonism in shaping Ganymede's complex icy surface, we perform a detailed mapping of key examples of strike-slip morphologies from Galileo and Voyager imagery. We investigate the role of tidal stresses using the numerical code SatStress to calculate both diurnal and non-synchronous rotation (NSR) tidal stresses at Ganymede's surface. We then compute Coulomb failure conditions, which are a function of fault strike and regional stress magnitudes, for the mapped regions. Previous work at Dardanus Sulcus, Tiamat Sulcus, and Uruk Sulcus, regions with an inferred right-lateral sense of slip, suggests that global tidal stress models of both diurnal and NSR stress contributions readily generate shear and normal stress magnitudes ( 1.1 MPa) that could give rise to shear failure at depth ( 2 km). While models for both Dardanus and Tiamat Sulcus accurately predict right-lateral motion, stresses at Uruk Sulcus suggest a left-lateral sense of slip for the current fault strike orientation. This presents an opportunity to examine the role of temporal fault strike variations, as well as changes in the distribution of stresses, on shear failure and sense of slip. We find that models with a 10 - 40° clockwise rotation of Uruk's fault strike predict the expected right-lateral slip. Strain ellipses derived from morphological mapping efforts suggest as much as 50° of rotation may have occurred here. Such a rotation may be plausible if the feature formed in a different orientation than it presently possesses due to migration of the ice shell. Further investigation of changes in distribution of stress, perhaps due to a NSR bulge shift or true polar wander, help provide insight into how features on Ganymede may have evolved through time.

  20. It's just sand between the toes: how particle size and shape variation affect running performance and kinematics in a generalist lizard.

    Science.gov (United States)

    Bergmann, Philip J; Pettinelli, Kyle J; Crockett, Marian E; Schaper, Erika G

    2017-10-15

    Animals must cope with and be able to move effectively on a variety of substrates. Substrates composed of granular media, such as sand and gravel, are extremely common in nature, and vary tremendously in particle size and shape. Despite many studies of the properties of granular media and comparisons of locomotion between granular and solid substrates, the effects of systematically manipulating these media on locomotion is poorly understood. We studied granular media ranging over four orders of magnitude in particle size, and differing in the amount of particle shape variation, to determine how these factors affected substrate physical properties and sprinting in the generalist lizard Eremias arguta We found that media with intermediate particle sizes had high bulk densities, low angles of stability and low load-bearing capacities. Rock substrates with high shape variation had higher values for all three properties than glass bead substrates with low shape variation. We found that E. arguta had the highest maximum velocities and accelerations on intermediate size particles, and higher velocities on rock than glass beads. Lizards had higher stride frequencies and lower duty factors on intermediate particle size substrates, but their stride lengths did not change with substrate. Our findings suggest that sand and gravel may represent different locomotor challenges for animals. Sand substrates provide animals with an even surface for running, but particles shift underfoot. In contrast, gravel particles are heavy, so move far less underfoot, yet provide the animal with an uneven substrate. © 2017. Published by The Company of Biologists Ltd.

  1. Approximation to SOC stocks variations over time affected by land use changes in a Mediterranean mountain agricultural catchment

    Science.gov (United States)

    Lizaga, Ivan; Quijano, Laura; Gaspar, Leticia; Navas, Ana

    2017-04-01

    Land use conversion from cropland to natural vegetation can be an effective mechanism to reduce soil C losses and promote soil C recovery affecting the storage of C in soils. Understanding how anthropogenic land use changes lead to implications for soil C storage and how it affects the distribution of total carbon provide information that will support the application of best management practices to restore or maintain soil C. Agricultural abandonment is one of the most important land use changes in recent decades in Mediterranean catchments. This land use change can play a key role on ecosystems functions that, can be particularly relevant in Mediterranean mountain landscapes where soils are fragile and prone to erosion. This research aims to evaluate the effects of land use changes on SOC stocks at catchment scale. To this purpose, a total of 98 soil samples were collected on a 500 m grid in the Barués catchment (23 km2) with elevation ranges between 535 and 964 m.a.s.l and mean slope of 16°. The study area is a Mediterranean mountain ephemeral stream catchment located in the central part of the Ebro Basin in northeast Spain (4699000N 647300E) where in recent decades the abandonment of cultivated areas was the main land use change. The sampling points are distributed proportionally in function of the percentage area occupied by the different land uses to be statistically comparable. The SOC content was measured by dry combustion method with LECO equipment. A soil type map of the catchment and two land use maps were created based on two different scenarios using aerial photography for 1957 and 2010 in order to compare how land use has affected carbon storage in the catchment. Six main soil types were identified named Calcisols, Cambisols, Fluvisols, Leptosols and Regosols. The results show an important decrease (71%) of the cultivated land that in 1957 extended over 13.4 km2 whereas today only occupies 3.8 km2 while forested areas increased from 9.2 km2 in 1957

  2. Genetic variations in magnesium-related ion channels may affect diabetes risk among African American and Hispanic American women.

    Science.gov (United States)

    Chan, Kei Hang K; Chacko, Sara A; Song, Yiqing; Cho, Michele; Eaton, Charles B; Wu, Wen-Chih H; Liu, Simin

    2015-03-01

    important associations between genetic variations in magnesium-related ion channel genes and T2D risk in AA and HA women that vary by amount of magnesium intake. © 2015 American Society for Nutrition.

  3. Complex, Dynamic Combination of Physical, Chemical and Nutritional Variables Controls Spatio-Temporal Variation of Sandy Beach Community Structure

    Science.gov (United States)

    Ortega Cisneros, Kelly; Smit, Albertus J.; Laudien, Jürgen; Schoeman, David S.

    2011-01-01

    Sandy beach ecological theory states that physical features of the beach control macrobenthic community structure on all but the most dissipative beaches. However, few studies have simultaneously evaluated the relative importance of physical, chemical and biological factors as potential explanatory variables for meso-scale spatio-temporal patterns of intertidal community structure in these systems. Here, we investigate macroinfaunal community structure of a micro-tidal sandy beach that is located on an oligotrophic subtropical coast and is influenced by seasonal estuarine input. We repeatedly sampled biological and environmental variables at a series of beach transects arranged at increasing distances from the estuary mouth. Sampling took place over a period of five months, corresponding with the transition between the dry and wet season. This allowed assessment of biological-physical relationships across chemical and nutritional gradients associated with a range of estuarine inputs. Physical, chemical, and biological response variables, as well as measures of community structure, showed significant spatio-temporal patterns. In general, bivariate relationships between biological and environmental variables were rare and weak. However, multivariate correlation approaches identified a variety of environmental variables (i.e., sampling session, the C∶N ratio of particulate organic matter, dissolved inorganic nutrient concentrations, various size fractions of photopigment concentrations, salinity and, to a lesser extent, beach width and sediment kurtosis) that either alone or combined provided significant explanatory power for spatio-temporal patterns of macroinfaunal community structure. Overall, these results showed that the macrobenthic community on Mtunzini Beach was not structured primarily by physical factors, but instead by a complex and dynamic blend of nutritional, chemical and physical drivers. This emphasises the need to recognise ocean-exposed sandy

  4. MAPT Genetic Variation and Neuronal Maturity Alter Isoform Expression Affecting Axonal Transport in iPSC-Derived Dopamine Neurons.

    Science.gov (United States)

    Beevers, Joel E; Lai, Mang Ching; Collins, Emma; Booth, Heather D E; Zambon, Federico; Parkkinen, Laura; Vowles, Jane; Cowley, Sally A; Wade-Martins, Richard; Caffrey, Tara M

    2017-08-08

    The H1 haplotype of the microtubule-associated protein tau (MAPT) locus is genetically associated with neurodegenerative diseases, including Parkinson's disease (PD), and affects gene expression and splicing. However, the functional impact on neurons of such expression differences has yet to be fully elucidated. Here, we employ extended maturation phases during differentiation of induced pluripotent stem cells (iPSCs) into mature dopaminergic neuronal cultures to obtain cultures expressing all six adult tau protein isoforms. After 6 months of maturation, levels of exon 3+ and exon 10+ transcripts approach those of adult brain. Mature dopaminergic neuronal cultures display haplotype differences in expression, with H1 expressing 22% higher levels of MAPT transcripts than H2 and H2 expressing 2-fold greater exon 3+ transcripts than H1. Furthermore, knocking down adult tau protein variants alters axonal transport velocities in mature iPSC-derived dopaminergic neuronal cultures. This work links haplotype-specific MAPT expression with a biologically functional outcome relevant for PD. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  5. MAPT Genetic Variation and Neuronal Maturity Alter Isoform Expression Affecting Axonal Transport in iPSC-Derived Dopamine Neurons

    Directory of Open Access Journals (Sweden)

    Joel E. Beevers

    2017-08-01

    Full Text Available The H1 haplotype of the microtubule-associated protein tau (MAPT locus is genetically associated with neurodegenerative diseases, including Parkinson's disease (PD, and affects gene expression and splicing. However, the functional impact on neurons of such expression differences has yet to be fully elucidated. Here, we employ extended maturation phases during differentiation of induced pluripotent stem cells (iPSCs into mature dopaminergic neuronal cultures to obtain cultures expressing all six adult tau protein isoforms. After 6 months of maturation, levels of exon 3+ and exon 10+ transcripts approach those of adult brain. Mature dopaminergic neuronal cultures display haplotype differences in expression, with H1 expressing 22% higher levels of MAPT transcripts than H2 and H2 expressing 2-fold greater exon 3+ transcripts than H1. Furthermore, knocking down adult tau protein variants alters axonal transport velocities in mature iPSC-derived dopaminergic neuronal cultures. This work links haplotype-specific MAPT expression with a biologically functional outcome relevant for PD.

  6. MYBs affect the variation in the ratio of anthocyanin and flavanol in fruit peel and flesh in response to shade.

    Science.gov (United States)

    Lu, Yanfen; Bu, Yufen; Hao, Suxiao; Wang, Yaru; Zhang, Jie; Tian, Ji; Yao, Yuncong

    2017-03-01

    Fruit pigment accumulation, which represents an important indicator of nutrient quality and appearance value, is often affected by low light under rain, cloud, fog and haze conditions during the veraison period. It is not known whether continuous low light interferes with the production and accumulation of secondary metabolites in veraison fruit. In this paper, we measured pigments and the transcriptional level of genes related to secondary metabolites, i.e., flavonoid biosynthesis in the peel and flesh of Malus crabapple 'Radiant' fruit in response to normal light and shade from 10th July to 30th August. The results showed crosstalk between the flavonoid biosynthetic genes and the involvement of key transcription factors such as McMYB4, McMYB7, McMYB10, and McMYB16 in the regulation of the ratio of anthocyanins and flavanols, which accounted for the different colouration of the fruit peel and flesh under shade conditions. A model is proposed for the regulation of the flavonoid pathway in the peel and flesh of 'Radiant' fruit based on our study results. Moreover, the molecular mechanism for 'Radiant' fruit colouration provides reference information for understanding the light regulatory mechanism involved in the biosynthesis of flavonoids and for designing the next generation of apple breeding. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Genetic variation of the α2b-adrenoceptor affects neural correlates of successful emotional memory formation.

    Science.gov (United States)

    Urner, Maren; van Wingen, Guido; Franke, Barbara; Rijpkema, Mark; Fernández, Guillén; Tendolkar, Indira

    2011-12-01

    Enhanced memory for emotionally charged events helps us to remember potentially vital information. There are large interindividual differences in emotional-memory enhancement, but little is known about their neurobiological basis. Recently, a functional deletion variant of the gene that codes for the α2b-adrenoceptor (ADRA2B) has been shown to affect memory for emotional experiences. Initial neuroimaging evidence linked this behavioral effect to increased amygdala activity, but its influence on successful memory processing remains unknown. Therefore, the aim of this study was to investigate the effect of the common deletion in the ADRA2B gene on neural activity related to specific mnemonic processing, successful memory formation, and retrieval. Twenty-three noncarriers (10 males) and 28 deletion carriers (13 males) with a mean age of 24 years were investigated while performing an emotional-learning task with sad and happy scenes. Functional magnetic resonance imaging was acquired both during memory formation and retrieval. Although there were no differences in memory performance between groups, the common deletion variant of ADRA2B was related to enhanced activity in the amygdala and inferior frontal gyrus during successful emotional memory formation, but not retrieval. Deletion carriers showed a larger differential response in these brain regions between later-remembered and later-forgotten stimuli than nondeletion carriers did. Our results demonstrate that the ADRA2B polymorphism influences emotional memory formation but not memory retrieval in the amygdala and left inferior frontal gyrus. Copyright © 2011 Wiley Periodicals, Inc.

  8. Weather daily variation in winter and its effect on behavior and affective states in day-care children

    Science.gov (United States)

    Ciucci, Enrica; Calussi, Pamela; Menesini, Ersilia; Mattei, Alessandra; Petralli, Martina; Orlandini, Simone

    2011-05-01

    This study aimed to analyze the impact of winter weather conditions on young children's behavior and affective states by examining a group of 61 children attending day-care centers in Florence (Italy). Participants were 33 males, 28 females and their 11 teachers. The mean age of the children at the beginning of the observation period was 24.1 months. The day-care teachers observed the children's behavioral and emotional states during the morning before their sleeping time and filled in a questionnaire for each baby five times over a winter period of 3 weeks. Air temperature, relative humidity, air pressure and solar radiation data were collected every 15 min from a weather station located in the city center of Florence. At the same time, air temperature and relative humidity data were collected in the classroom and in the garden of each day-care center. We used multilevel linear models to evaluate the extent to which children's emotional and behavioral states could be predicted by weather conditions, controlling for child characteristics (gender and age). The data showed that relative humidity and solar radiation were the main predictors of the children's emotional and behavioral states. The outdoor humidity had a significant positive effect on frustration, sadness and aggression; solar radiation had a significant negative effect only on sadness, suggesting that a sunny winter day makes children more cheerful. The results are discussed in term of implications for parents and teachers to improve children's ecological environment.

  9. Incorporation of digestate selectively affects physical, chemical and biochemical properties along with CO2 emissions in two contrasting agricultural soils in the Mediterranean area.

    Science.gov (United States)

    Badagliacca, Giuseppe; Petrovičová, Beatrix; Zumbo, Antonino; Romeo, Maurizio; Gullì, Tommaso; Martire, Luigi; Monti, Michele; Gelsomino, Antonio

    2017-04-01

    Soil incorporation of digestate represents a common practice to dispose the solid residues from biogas producing plants. Although the digestate constitutes a residual biomass rich in partially decomposed organic matter and nutrients, whose content is often highly variable and unbalanced, its potential fertilizer value can vary considerably depending on the recipient soil properties. The aim of the work was to assess short-term changes in the fertility status of two contrasting agricultural soils in Southern Italy (Calabria), olive grove on a clay acid soil (Typic Hapludalfs) and citrus grove on a sandy loam slightly calcareous soil (Typic Xerofluvents), respectively located along the Tyrrhenian or the Ionian coast. An amount of 30 t ha-1 digestate was incorporated into the soil by ploughing. Unamended tilled soil was used as control. The following soil physical, chemical and biochemical variables were monitored during the experimental period: aggregate stability, pH, electrical conductivity, organic C, total N, Olsen-P, N-NH4+, N-NO3-, microbial biomass carbon (MBC), microbial biomass nitrogen (MBN) and the mineralization quotient (qM). Moreover, in the olive grove soil CO2 emissions have been continuously measured at field scale for 5 months after digestate incorporation. Digestate application in both site exerted a significant positive effect on soil aggregate stability with a greater increase in clay than in sandy loam soil. Over the experimental period, digestate considerably affected the nutrient availability, namely Olsen-P, N-NH4+, N-NO3-, along with the electrical conductivity. The soil type increased significantly the soil N-NH4+ content, which was always higher in the olive than in citrus grove soil. N-NO3- content was markedly increased soon after the organic amendment, followed by a seasonal decline more evident in the sandy loam soil. Moreover, soil properties as CaCO3 content and the pH selectively affected the Olsen-P dynamics. No appreciable

  10. Chemical variations within and between the clasts, and the matrix of the Abee enstatite chondrite suggest an impact-based differentiation mechanism

    Science.gov (United States)

    Higgins, Michael D.; Martin, Pierre-Etienne M. C.

    2018-01-01

    Abee is an enstatite chondrite breccia dominantly composed of kamacite, enstatite, silica, plagioclase, troilite and niningerite. Clasts are up to 220 mm long and vary in shape from angular to rounded. Some clasts are zoned with kamacite-enriched rims that follow the edge of the clast. Spatial compositional variations were examined in a small block to find out more about the petrological processes that produced this rock, particularly the relationship between the clasts, the matrix and the cores/rims of the zoned clasts. Compositional maps produced using a focussed-beam XRF were segmented into clasts and matrix, and rims and cores where possible. Compositions of most clasts, matrix and rim/cores define a simple, linear trend on simple variation diagrams. If it is assumed that all components were derived from an original homogeneous composition then the variation can be explained either by addition of kamacite or by loss of all other phases. Within this overall compositional variation the kamacite content generally increases as follows: matrix clasts ≈ zoned clast cores clasts ≈ zoned clast rims. Production of diversity by addition of kamacite to clasts and rim seems to require a complex history as the source cannot have been the current matrix. It is also difficult to produce the observed chemical variations and zoning by partial melting. However, differentiation by removal of all non-metallic phases may result from repeated impacts: Shock waves would deform kamacite whilst fracturing all other phases. The broken grains would then migrate towards the surface of the clasts where they would spall off into the matrix. This process would also lead to the observed rounding of some clasts. We propose that this shock-differentiation process be called 'smithing', as it resembles the ancient process of iron refining.

  11. Low strength ultrasonication positively affects the methanogenic granules toward higher AD performance. Part I: Physico-chemical characteristics

    DEFF Research Database (Denmark)

    Cho, S. K.; Hwang, Yuhoon; Kim, D. H.

    2013-01-01

    To elucidate the correlation between enhanced biogas production and changed physico-chemical properties of methanogenic granules after low strength ultrasonication, in this study, the effects of low strength ultrasonication on the settling velocity, permeability, porosity, and fluid collection ef...

  12. Attentional costs of walking are not affected by variations in lateral balance demands in young and older adults.

    Science.gov (United States)

    Mazaheri, Masood; Roerdink, Melvyn; Duysens, Jacques; Beek, Peter J; Peper, C Lieke E

    2016-05-01

    Increased attentional costs of walking in older adults have been attributed to age-related changes in visuomotor and/or balance control of walking. The present experiment was conducted to examine the hypothesis that attentional costs of walking vary with lateral balance demands during walking in young and older adults. Twenty young and twenty older adults walked on a treadmill at their preferred walking speed under five conditions: unconstrained normal walking, walking on projected visual lines corresponding to either the participant's preferred step width or 50% thereof (i.e. increased balance demand), and walking within low- and high-stiffness lateral stabilization frames (i.e. lower balance demands). Attentional costs were assessed using a probe reaction-time task during these five walking conditions, normalized to baseline performance as obtained during sitting. Both imposed step-width conditions were more attentionally demanding than the three other conditions, in the absence of any other significant differences between conditions. These effects were similar in the two groups. The results indicate that the attentional costs of walking were, in contrast to what has been postulated previously, not influenced by lateral balance demands. The observed difference in attentional costs between normal walking and both visual lines conditions suggests that visuomotor control processes, rather than balance control, strongly affect the attentional costs of walking. A tentative explanation of these results may be that visuomotor control processes are mainly governed by attention-demanding cortical processes, whereas balance is regulated predominantly subcortically. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Natural Variation in the VELVET Gene bcvel1 Affects Virulence and Light-Dependent Differentiation in Botrytis cinerea

    Science.gov (United States)

    Schumacher, Julia; Pradier, Jean-Marc; Simon, Adeline; Traeger, Stefanie; Moraga, Javier; Collado, Isidro González; Viaud, Muriel; Tudzynski, Bettina

    2012-01-01

    Botrytis cinerea is an aggressive plant pathogen causing gray mold disease on various plant species. In this study, we identified the genetic origin for significantly differing phenotypes of the two sequenced B. cinerea isolates, B05.10 and T4, with regard to light-dependent differentiation, oxalic acid (OA) formation and virulence. By conducting a map-based cloning approach we identified a single nucleotide polymorphism (SNP) in an open reading frame encoding a VELVET gene (bcvel1). The SNP in isolate T4 results in a truncated protein that is predominantly found in the cytosol in contrast to the full-length protein of isolate B05.10 that accumulates in the nuclei. Deletion of the full-length gene in B05.10 resulted in the T4 phenotype, namely light-independent conidiation, loss of sclerotial development and oxalic acid production, and reduced virulence on several host plants. These findings indicate that the identified SNP represents a loss-of-function mutation of bcvel1. In accordance, the expression of the B05.10 copy in T4 rescued the wild-type/B05.10 phenotype. BcVEL1 is crucial for full virulence as deletion mutants are significantly hampered in killing and decomposing plant tissues. However, the production of the two best known secondary metabolites, the phytotoxins botcinic acid and botrydial, are not affected by the deletion of bcvel1 indicating that other factors are responsible for reduced virulence. Genome-wide expression analyses of B05.10- and Δbcvel1-infected plant material revealed a number of genes differentially expressed in the mutant: while several protease- encoding genes are under-expressed in Δbcvel1 compared to the wild type, the group of over-expressed genes is enriched for genes encoding sugar, amino acid and ammonium transporters and glycoside hydrolases reflecting the response of Δbcvel1 mutants to nutrient starvation conditions. PMID:23118899

  14. Nitrous oxide emission and denitrifier communities in drip-irrigated calcareous soil as affected by chemical and organic fertilizers.

    Science.gov (United States)

    Tao, Rui; Wakelin, Steven A; Liang, Yongchao; Hu, Baowei; Chu, Guixin

    2018-01-15

    The effects of consecutive application of chemical fertilizer with or without organic fertilizer on soil N 2 O emissions and denitrifying community structure in a drip-irrigated field were determined. The four fertilizer treatments were (i) unfertilized, (ii) chemical fertilizer, (iii) 60% chemical fertilizer plus cattle manure, and (iv) 60% chemical fertilizer plus biofertilizer. The treatments with organic amendments (i.e. cattle manure and biofertilizer) reduced cumulative N 2 O emissions by 4.9-9.9%, reduced the N 2 O emission factor by 1.3-42%, and increased denitrifying enzyme activities by 14.3-56.2%. The nirK gene copy numbers were greatest in soil which received only chemical fertilizer. In contrast, nirS- and nosZ-copy numbers were greatest in soil amended with chemical fertilizer plus biofertilizer. Chemical fertilizer application with or without organic fertilizer significantly changed the community structure of nirK-type denitrifiers relative to the unfertilized soil. In comparison, the nirS- and nosZ-type denitrifier genotypes varied in treatments receiving organic fertilizer but not chemical fertilizer alone. The changes in the denitrifier communities were closely associated with soil organic carbon (SOC), NO 3 - , NH 4 + , water holding capacity, and soil pH. Modeling indicated that N 2 O emissions in this soil were primarily associated with the abundance of nirS type denitrifying bacteria, SOC, and NO 3 - . Overall, our findings indicate that (i) the organic fertilizers increased denitrifying enzyme activity, increased denitrifying-bacteria gene copy numbers, but reduced N 2 O emissions, and (ii) nirS- and nosZ-type denitrifiers were more sensitive than nirK-type denitrifiers to the organic fertilizers. Copyright © 2017. Published by Elsevier B.V.

  15. Variation in sex pheromone emission does not reflect immunocompetence but affects attractiveness of male burying beetles—a combination of laboratory and field experiments

    Science.gov (United States)

    Chemnitz, Johanna; Bagrii, Nadiia; Ayasse, Manfred; Steiger, Sandra

    2017-08-01

    Life history theory predicts a trade-off between male sexual trait expression and immunocompetence. Using burying beetles, Nicrophorus vespilloides, as a model, we investigated the relationship between male immune function, sex pheromone emission, and attractiveness under field conditions. In the first experiment, we tested whether there is a positive correlation between immune capacity, sex pheromone characteristics (quantity, relative composition, and time invested in pheromone emission), and male attractiveness. As a measurement of immune capacity, we used an individual's encapsulation ability against a novel antigen. In the second experiment, we specifically examined whether a trade-off between chemical trait expression and immune function existed. To this end, we challenged the immune system and measured the subsequent investment in sex pheromone emission and the attractiveness of the male under field conditions. We found that a male's immunocompetence was neither related to the emission of the male's sex pheromone nor to its attractiveness in the field. Furthermore, none of the immune-challenge treatments affected the subsequent investment in pheromone emission or number of females attracted. However, we showed that the same males that emitted a high quantity of their sex pheromone in the laboratory were able to attract more females in the field. Our data suggest that the chemical signal is not a reliable predictor of a male's immunocompetence but rather is a general important fitness-related trait, with a higher emission of the sex pheromone measured in the laboratory directly affecting the attractiveness of a male under field conditions.

  16. Short-term biological variation of clinical chemical values in dumeril's monitors (Varanus dumerili)

    DEFF Research Database (Denmark)

    Bertelsen, Mads Frost; Kjelgaard-Hansen, Mads Jens; Howell, Jennifer R.

    2007-01-01

    for that animal. Only for potassium and AST did the index of individuality suggest that the use of reference values may be warranted. Uric acid, globulin, glucose, and amylase fell in a gray zone, where population-based ranges should be used with caution. The critical difference indicates the difference between...... two consecutive analytical results that may be safely ascribed to natural variation. In the present study critical difference varied from 7 and 11%, respectively, for sodium and chloride to 75 and 125% for uric acid and AST....

  17. Spatial and seasonal variations of the chemical, mineralogical and morphological features of quasi-ultrafine particles (PM{sub 0.49}) at urban sites

    Energy Technology Data Exchange (ETDEWEB)

    Samara, Constantini, E-mail: csamara@chem.auth.gr [Department of Chemistry, Environmental Pollution Control Laboratory, Aristotle University, GR-54124 Thessaloniki (Greece); Kantiranis, Nikolaos; Kollias, Panagiotis [Department of Geology, Division of Mineralogy-Petrology-Economic Geology, Aristotle University, GR-54124 Thessaloniki (Greece); Planou, Styliani; Kouras, Athanasios; Besis, Athanasios; Manoli, Evangelia; Voutsa, Dimitra [Department of Chemistry, Environmental Pollution Control Laboratory, Aristotle University, GR-54124 Thessaloniki (Greece)

    2016-05-15

    Combining chemical and physical-structural information of particles is a key issue in PM investigations. Chemical, mineralogical, and morphological characterization of quasi-ultrafine particles (PM{sub 0.49}) was carried out at two urban sites of varying traffic-influence (roadside and urban background) in Thessaloniki, northern Greece, during the cold and the warm period of 2013. Bulk analyses of chemical species included organic and elemental carbon (OC, EC), water soluble organic carbon (WSOC), ionic species (NO{sub 3}{sup −}, SO{sub 4}{sup 2−}, Cl{sup −}, Na{sup +}, NH{sub 4}{sup +}, K{sup +}, Mg{sup 2+}, Ca{sup 2+}) and trace elements (As, Ba, Cd, Cr, Cu, Fe, Pb, Mn, Ni, Zn, Pt, Pd, Rh, Ru, and Ir). X-ray diffractometry (XRD) was employed for the mineralogical analysis of PM{sub 0.49} in order to identify and quantify amorphous and crystalline phases. In addition, scanning electron microscopy coupled with energy dispersive spectrometry (SEM-EDS) was employed for morphological characterization and elemental microanalysis of individual particles. Findings of this work could provide the basis for designing epidemiological and toxicity studies to mitigate population exposure to UFPs. - Highlights: • Chemical, mineralogical, and morphological features of PM{sub 0.49} were investigated. • PM{sub 0.49} levels were highest at the traffic site during wintertime. • PM{sub 0.49} mass was dominated by OM, minerals, EC and secondary ions. • Chemical mass closure showed significant seasonal and spatial variations. • Mineralogical composition was dominated by the organic amorphous phase.

  18. Chemical variation for fiber cuticular wax levels in upland cotton (Gossypium hirsutum) evaluated under contrasting irrigation regimes

    Science.gov (United States)

    Fiber quality is important for the sale of bulk fiber to textile mills for processing but is affected by many environmental factors, including water deficit. These environmental factors have made it difficult to identify the primary determinants of fiber quality which has spurred renewed research ef...

  19. Exploring Conceptual Frameworks of Models of Atomic Structures and Periodic Variations, Chemical Bonding, and Molecular Shape and Polarity: A Comparison of Undergraduate General Chemistry Students with High and Low Levels of Content Knowledge

    Science.gov (United States)

    Wang, Chia-Yu; Barrow, Lloyd H.

    2013-01-01

    The purpose of the study was to explore students' conceptual frameworks of models of atomic structure and periodic variations, chemical bonding, and molecular shape and polarity, and how these conceptual frameworks influence their quality of explanations and ability to shift among chemical representations. This study employed a purposeful sampling…

  20. Osteoblast adhesion, migration, and proliferation variations on chemically patterned nanocrystalline diamond films evaluated by live-cell imaging.

    Science.gov (United States)

    Broz, Antonin; Ukraintsev, Egor; Kromka, Alexander; Rezek, Bohuslav; Hubalek Kalbacova, Marie

    2017-05-01

    Cell fate modulation by adapting the surface of a biocompatible material is nowadays a challenge in implantology, tissue engineering as well as in construction of biosensors. Nanocrystalline diamond (NCD) thin films are considered promising in these fields due to their extraordinary physical and chemical properties and diverse ways in which they can be modified structurally and chemically. The initial cell distribution, the rate of cell adhesion, distance of cell migration and also the cell proliferation are influenced by the NCD surface termination. Here, we use real-time live-cell imaging to investigate the above-mentioned processes on oxidized NCD (NCD-O) and hydrogenated NCD (NCD-H) to elucidate cell preference to the NCD-O especially on surfaces with microscopic surface termination patterns. Cells adhere more slowly and migrate farther on NCD-H than on NCD-O. Cells seeded with a fetal bovine serum (FBS) supplement in the medium move across the surface prior to adhesion. In the absence of FBS, the cells adhere immediately, but still exhibit different migration and proliferation on NCD-O/H regions. We discuss the impact of these effects on the formation of cell arrays on micropatterned NCD. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1469-1478, 2017. © 2017 Wiley Periodicals, Inc.

  1. Chemical or Biological Terrorist Attacks: An Analysis of the Preparedness of Hospitals for Managing Victims Affected by Chemical or Biological Weapons of Mass Destruction

    Directory of Open Access Journals (Sweden)

    Russell L. Bennett

    2006-03-01

    Full Text Available The possibility of a terrorist attack employing the use of chemical or biological weapons of mass destruction (WMD on American soil is no longer an empty threat, it has become a reality. A WMD is defined as any weapon with the capacity to inflict death and destruction on such a massive scale that its very presence in the hands of hostile forces is a grievous threat. Events of the past few years including the bombing of the World Trade Center in 1993, the Murrah Federal Building in Oklahoma City in 1995 and the use of planes as guided missiles directed into the Pentagon and New York’s Twin Towers in 2001 (9/11 and the tragic incidents involving twentythree people who were infected and five who died as a result of contact with anthrax-laced mail in the Fall of 2001, have well established that the United States can be attacked by both domestic and international terrorists without warning or provocation. In light of these actions, hospitals have been working vigorously to ensure that they would be “ready” in the event of another terrorist attack to provide appropriate medical care to victims. However, according to a recent United States General Accounting Office (GAO nationwide survey, our nation’s hospitals still are not prepared to manage mass causalities resulting from chemical or biological WMD. Therefore, there is a clear need for information about current hospital preparedness in order to provide a foundation for systematic planning and broader discussions about relative cost, probable effectiveness, environmental impact and overall societal priorities. Hence, the aim of this research was to examine the current preparedness of hospitals in the State of Mississippi to manage victims of terrorist attacks involving chemical or biological WMD. All acute care hospitals in the State were selected for inclusion in this study. Both quantitative and qualitative methods were utilized for data collection

  2. Chemical or biological terrorist attacks: an analysis of the preparedness of hospitals for managing victims affected by chemical or biological weapons of mass destruction.

    Science.gov (United States)

    Bennett, Russell L

    2006-03-01

    The possibility of a terrorist attack employing the use of chemical or biological weapons of mass destruction (WMD) on American soil is no longer an empty threat, it has become a reality. A WMD is defined as any weapon with the capacity to inflict death and destruction on such a massive scale that its very presence in the hands of hostile forces is a grievous threat. Events of the past few years including the bombing of the World Trade Center in 1993, the Murrah Federal Building in Oklahoma City in 1995 and the use of planes as guided missiles directed into the Pentagon and New York's Twin Towers in 2001 (9/11) and the tragic incidents involving twentythree people who were infected and five who died as a result of contact with anthrax-laced mail in the Fall of 2001, have well established that the United States can be attacked by both domestic and international terrorists without warning or provocation. In light of these actions, hospitals have been working vigorously to ensure that they would be "ready" in the event of another terrorist attack to provide appropriate medical care to victims. However, according to a recent United States General Accounting Office (GAO) nationwide survey, our nation's hospitals still are not prepared to manage mass causalities resulting from chemical or biological WMD. Therefore, there is a clear need for information about current hospital preparedness in order to provide a foundation for systematic planning and broader discussions about relative cost, probable effectiveness, environmental impact and overall societal priorities. Hence, the aim of this research was to examine the current preparedness of hospitals in the State of Mississippi to manage victims of terrorist attacks involving chemical or biological WMD. All acute care hospitals in the State were selected for inclusion in this study. Both quantitative and qualitative methods were utilized for data collection and analysis. Six hypotheses were tested. Using a questionnaire

  3. Chemical or Biological Terrorist Attacks: An Analysis of the Preparedness of Hospitals for Managing Victims Affected by Chemical or Biological Weapons of Mass Destruction

    Science.gov (United States)

    Bennett, Russell L.

    2006-01-01

    The possibility of a terrorist attack employing the use of chemical or biological weapons of mass destruction (WMD) on American soil is no longer an empty threat, it has become a reality. A WMD is defined as any weapon with the capacity to inflict death and destruction on such a massive scale that its very presence in the hands of hostile forces is a grievous threat. Events of the past few years including the bombing of the World Trade Center in 1993, the Murrah Federal Building in Oklahoma City in 1995 and the use of planes as guided missiles directed into the Pentagon and New York’s Twin Towers in 2001 (9/11) and the tragic incidents involving twenty-three people who were infected and five who died as a result of contact with anthrax-laced mail in the Fall of 2001, have well established that the United States can be attacked by both domestic and international terrorists without warning or provocation. In light of these actions, hospitals have been working vigorously to ensure that they would be “ready” in the event of another terrorist attack to provide appropriate medical care to victims. However, according to a recent United States General Accounting Office (GAO) nationwide survey, our nation’s hospitals still are not prepared to manage mass causalities resulting from chemical or biological WMD. Therefore, there is a clear need for information about current hospital preparedness in order to provide a foundation for systematic planning and broader discussions about relative cost, probable effectiveness, environmental impact and overall societal priorities. Hence, the aim of this research was to examine the current preparedness of hospitals in the State of Mississippi to manage victims of terrorist attacks involving chemical or biological WMD. All acute care hospitals in the State were selected for inclusion in this study. Both quantitative and qualitative methods were utilized for data collection and analysis. Six hypotheses were tested. Using a

  4. Simultaneous quantitative determination of 20 active components in the traditional Chinese medicine formula Zhi-Zi-Da-Huang decoction by liquid chromatography coupled with mass spectrometry: application to study the chemical composition variations in different combinations.

    Science.gov (United States)

    Tang, Zheng; Yin, Ran; Bi, Kaishun; Zhu, Heyun; Han, Fei; Chen, Kelin; Wang, Fenrong

    2015-09-01

    Zhi-Zi-Da-Huang decoction (ZZDHD), a classical traditional Chinese medicine (TCM) prescription composed of four herbal medicines, has been widely used in treating various hepatobiliary disorders for a long time. The objective of this study was to develop a sensitive and efficient liquid chromatography coupled with mass spectrometry (LC-MS) method for quantitative determination of 20 active constituents, including three iridoid glycosides, 11 flavonoids, three anthraquinones and three tannins in ZZDHD. Separation was achieved on a phenomenex kinetex C18 column (150 × 4.6 mm, 2.6 µm) using gradient elution with a mobile phase consisting of acetonitrile and 0.1% formic acid in water. Detection was performed with electrospray ionization source in the negative ionization and selected ion monitoring mode. The established method was validated by determining the linearity (r(2) ≥ 0.9983), limit of quantification (0.16-300 ng/mL), precision (RSD ≤ 4.6%), average recovery (96.0-105.6%), repeatability (RSD ≤ 3.2%) and stability (RSD ≤ 4.5%). Then, the method was successfully applied to investigate the chemical composition variations owing to the interaction between the four component herbs of ZZDHD during the extraction process. It was found that different combinations of the herbs affect the extraction efficiency of chemical constituents in different ways. The validated LC-MS method provides a meaningful basis for quality control and further research on ZZDHD. Copyright © 2015 John Wiley & Sons, Ltd.

  5. Kinetics of Hydrogen Radical Reactions with Toluene Including Chemical Activation Theory Employing System-Specific Quantum RRK Theory Calibrated by Variational Transition State Theory.

    Science.gov (United States)

    Bao, Junwei Lucas; Zheng, Jingjing; Truhlar, Donald G

    2016-03-02

    Pressure-dependent reactions are ubiquitous in combustion and atmospheric chemistry. We employ a new calibration procedure for quantum Rice-Ramsperger-Kassel (QRRK) unimolecular rate theory within a chemical activation mechanism to calculate the pressure-falloff effect of a radical association with an aromatic ring. The new theoretical framework is applied to the reaction of H with toluene, which is a prototypical reaction in the combustion chemistry of aromatic hydrocarbons present in most fuels. Both the hydrogen abstraction reactions and the hydrogen addition reactions are calculated. Our system-specific (SS) QRRK approach is adjusted with SS parameters to agree with multistructural canonical variational transition state theory with multidimensional tunneling (MS-CVT/SCT) at the high-pressure limit. The new method avoids the need for the usual empirical estimations of the QRRK parameters, and it eliminates the need for variational transition state theory calculations as a function of energy, although in this first application we do validate the falloff curves by comparing SS-QRRK results without tunneling to multistructural microcanonical variational transition state theory (MS-μVT) rate constants without tunneling. At low temperatures, the two approaches agree well with each other, but at high temperatures, SS-QRRK tends to overestimate falloff slightly. We also show that the variational effect is important in computing the energy-resolved rate constants. Multiple-structure anharmonicity, torsional-potential anharmonicity, and high-frequency-mode vibrational anharmonicity are all included in the rate computations, and torsional anharmonicity effects on the density of states are investigated. Branching fractions, which are both temperature- and pressure-dependent (and for which only limited data is available from experiment), are predicted as a function of pressure.

  6. Hydrology and geochemistry of a slag-affected aquifer and chemical characteristics of slag-affected ground water, northwestern Indiana and northeastern Illinois

    Science.gov (United States)

    Bayless, E. Randall; Greeman, T.K.; Harvey, C.C.

    1998-01-01

    ?aquifer interface. The solid-phase analyses indicated that calcite, dolomite, and quartz generally were present throughout the slag?aquifer system; barian celestite, cristobalite, manganese-bearing calcite, and minrecordite were present in fewer samples. Trace elements that are liberated from the slag may be incorporated as impurities during precipitation of major minerals, sorbed onto clays and other grainsize fractions not analyzed as part of this study, or present in low-abundance minerals that were not detected by the X-ray analysis. Mass-balance and speciation programs were used to identify geochemical processes that may be occurring as water infiltrates through the slag, flows into the aquifer, and discharges into Lake George. The geochemical models indicate that precipitation of calcite may be occurring where slag-affected water enters the aquifer. Models also indicate that dolomite precipitation and clay-mineral dissolution may be occurring at the slag?aquifer interface; however, dolomite precipitation is generally believed to require geologically long time periods. Silica may be dissolving where slag-affected ground water enters the aquifer and may be precipitating where slag-affected ground water discharges to the lakebed of Lake George. In addition to the site-specific study, a statistical analysis of regional water quality was done to compare ground water in wells affected and unaffected by slag. When com-pared to wells in background locations in the Calumet aquifer, wells screened in slag across northwestern Indiana and northeastern Illinois generally had relatively higher pH and specific-conductance values and relatively higher concentrations of alkalinity, dissolved solids, suspended solids, total organic carbon, calcium, potassium, sodium, chloride, aluminum, barium, and possibly magnesium, sulfate, chromium, cobalt, copper, cyanide, manganese, mercury, nickel, and vanadium. When compared to wells in slag and wells in background locations, ground water from immediat

  7. Seasonal variation in the chemical composition, antioxidant activity, and total phenolic content of Artemisia absinthium essential oils.

    Science.gov (United States)

    Mohammadi, A; Sani, T Ahmadzadeh; Ameri, A A; Imani, M; Golmakani, E; Kamali, H

    2014-01-01

    The genus Artemisia belonging to the Compositae (Asteraceae) family and many traditional uses from the Artemisia species were reported. Artemisia absinthium is one of the species in this genus and commonly used in the food industry in the preparation of aperitifs, bitters, and spirits. Evaluation of the effect of different harvesting stages on the composition of essential oil and antioxidant capacity of A. absinthium. Essential oils from the aerial parts of A. absinthium, collected in three stages (preflowering, flowering, and after-flowering) from plants grown in the North Khorasan province of Iran were obtained by steam distillation and the chemical composition of the oils was analyzed by gas chromatography-mass spectrometry and antioxidant activity and total phenolic content were determined by 2-diphenyl-1-picrylhydrazyl assay and Folin-Ciocalteu method. Analysis of the isolated oils revealed the presence of 44 compounds, mainly alpha-pinene, sabinene, beta-pinene, alpha-phellandrene, p-cymene and chamazulene. Alpha-phellandrene, and chamazulene were major compounds in preflowering stage, but beta-pinene and alpha-phellandrene were major in flowering and past-flowering stages. Flowering stage had highest yield and after flowering stage had lowest yield. The essential oil of preflowering stage had the highest amount of antioxidant compound (chamazulene). Preflowering stage with highest amount of phenolic compounds had the strongest antioxidant activity with the lowest amount of EC50. This study showed that the harvesting stage had significant effects on chemical composition and antioxidant properties of essential oils, and chamazulene is main compound for antioxidant activity in A. absinthium.

  8. Soil chemical and physical status in semideciduous Atlantic Forest fragments affected by atmospheric deposition in central-eastern São Paulo State, Brazil

    OpenAIRE

    Lopes MIMS; Ribeiro Dos Santos A; Zuliani Sandrin Camargo C; Bulbovas P; Giampaoli P; Domingos M

    2015-01-01

    The expansion of agricultural, urban and industrial areas in the São Paulo State (SE Brazil) led to the fragmentation of the original semideciduous Atlantic Fo­rest into small, patchy forest remnants. Anthropogenic activities produce a variety of pollutants affecting many ecological processes in these remaining fo­rest fragments through soil acidification and fertilization. In this study, we investigated the soil chemical and physical status of six forest remnants (Paulínia, Holambra, America...

  9. Changes in soil chemical properties as affected by pyrogenic organic matter amendment with different intensity and frequency

    NARCIS (Netherlands)

    Wang, Ruzhen; Zhang, Yulan; Cerda Bolinches, Artemio; Cao, Mingming; Zhang, Yongyong; Yin, Jinfei; Jiang, Yong; Chen, Lijun

    2017-01-01

    Pyrogenic organic matter (PyOM) has long been used as a soil amendment to improve soil physicochemical properties. However, few studies simultaneously investigated both intensities and frequencies of PyOM addition on soil chemical properties of soil base cations, soil pH buffering capacity (pHBC),

  10. Fungal strain and incubation period affect chemical composition and nutrient availability of wheat straw for rumen fermentation

    NARCIS (Netherlands)

    Tuyen, Van Dinh; Cone, J.W.; Baars, J.J.P.; Sonnenberg, A.S.M.; Hendriks, W.H.

    2012-01-01

    Eleven white-rot fungi were examined for their potency to degrade lignin and to improve the rumen fermentability of wheat straw. The straw was inoculated with the fungi and incubated under solid state conditions at 24 °C for 0–49 days to determine changes in in vitro gas production and chemical

  11. Chemical composition of needles and cambial activity of stems of Scots pine trees affected by air pollutants in Polish forests

    Science.gov (United States)

    Wojciech Dmuchowski; Ewa U. Kurczynska; Wieslaw Wloch

    1998-01-01

    The impact of environmental pollution is defined for the chemical composition of Scots pine (Pinus sylvestris L.) needles and cambial activity in the tree stems in Polish forests. The research investigated 20-year-old trees growing in two areas in significantly different levels of pollution. The highly polluted area was located near the Warsaw...

  12. Chemical form of selenium affects its uptake, transport and glutathione peroxidase activity in the human intestinal Caco-2 cell model

    Science.gov (United States)

    Determining the effect of selenium (Se) chemical form on uptake and transport in human intestinal cells is critical to assess Se bioavailability. In the present study, we measured the uptake and transport of various Se compounds in the human intestinal Caco-2 cell model. We found that two sources...

  13. Volcanological implications of crystal-chemical variations in clinopyroxenes from the Aeolian Arc, Southern Tyrrhenian Sea (Italy)

    Science.gov (United States)

    Nazzareni, Sabrina; Molin, Gianmario; Peccerillo, Angelo; Zanazzi, Pier Francesco

    2001-03-01

    Crystal chemistry and structural data for clinopyroxene from the Aeolian islands (Southern Tyrrhenian Sea, Italy) were determined with the aim of obtaining geobarometric information and exploring implications for the structure of volcanic plumbing systems. Cell and M1 site volumes for clinopyroxenes, which are known to decrease with increasing pressure of crystallization, revealed variable values, both within some single islands and along the entire arc, indicating polybaric conditions of crystallization. The lowest cell and M1 volumes were found at Filicudi, plotting close to values of clinopyroxenes from high-pressure ultramafic xenoliths entrained in alkali basalts. Indications of high-pressure crystallization were also found at Salina and, to a lesser extent, at Alicudi, all situated in the western sector of the Aeolian Arc. The central and eastern islands of Lipari, Vulcano, Panarea and Stromboli generally show higher values of cell parameters, suggesting crystallization in shallow magma chambers. These islands are characterized by the occurrence of large calderas, which are apparently lacking at Salina and Filicudi. Time-related variations were observed for cell and M1 volumes of clinopyroxene for some islands. At Salina, the early-erupted products display low values of cell parameters with respect to later activity, thus indicating a decrease in crystallization pressure with time. A similar, although less striking, pattern is observed at Alicudi and Lipari. An overall increase in cell parameters with time was observed at the scale of the entire arc. The observed variations in clinopyroxene structural parameters highlight the significance of pyroxene crystal chemistry for petrogenetic and volcanological interpretation. Correlation with time and the structural characteristics of volcanoes suggest significant regional and temporal modifications in the plumbing systems of Aeolian volcanoes. Clinopyroxenes from Filicudi and the older Salina crystallized at high

  14. Particulate pollution in urban Chongqing of southwest China: Historical trends of variation, chemical characteristics and source apportionment.

    Science.gov (United States)

    Chen, Yuan; Xie, Shao-Dong; Luo, Bin; Zhai, Chong-Zhi

    2017-04-15

    Chongqing, the largest megacity in southwest China, faces serious aerosol pollution but lacks information on particle characteristics and its sources. Official data released by Chongqing Environmental Protection Bureau demonstrated that urban PM10 concentrations decreased remarkably from 150μgm(-3) in 2000 to 90μgm(-3) in 2012. However, only several peer-reviewed studies paid attention to local fine particle (PM2.5) pollution. In the study, PM2.5 samples were obtained and subjected to chemical analysis in an urban site of the city during 2012 to 2013. The annual mean PM10 and PM2.5 concentrations in urban Chongqing were 103.9±52.5 and 75.4±42.2μgm(-3), respectively. PM2.5 showed a distinct seasonality of high concentration in winter and similar levels in other seasons. The average OC/EC (organic carbon/element carbon) ratio was 3.7 with more high-OC/EC ratio sources contribution in autumn and winter. The varying sources and formation mechanisms resulted in SO4(2-) and NH4(+) peaks in both summer and winter, whereas high nitrate concentration was only observed in winter. In the average mass closure, PM2.5 was composed of 23.0% SO4(2-), 11.7% NO3(-), 10.9% NH4(+), 30.8% OM (organic matter), 5.2% EC, 8.2% mineral dust, 0.6% TEO (trace elements), 1.0% Cl(-) and 1.1% K(+), while exhibiting large seasonal variability. Using positive matrix factorization (PMF), six sources were apportioned in PM2.5: secondary inorganic aerosols, coal combustion, other industrial pollution, soil dust, vehicular emission, and metallurgical industry. The annual mean contribution of above sources to PM2.5 was 37.5, 22.0, 17.5, 11.0, 9.8 and 2.2%, respectively. Coal combustion was identified by As tracer and dominated the primary sources of PM2.5, while the two different industrial sources were characterized by Cr and Mo, Co, Ni, and Se, respectively. The study is of great importance in characterizing the historical trends, current chemical characteristics and sources of fine particles in

  15. Seasonal variations in high time-resolved chemical compositions, sources, and evolution of atmospheric submicron aerosols in the megacity Beijing

    Science.gov (United States)

    Hu, Wei; Hu, Min; Hu, Wei-Wei; Zheng, Jing; Chen, Chen; Wu, Yusheng; Guo, Song

    2017-08-01

    A severe regional haze problem in the megacity Beijing and surrounding areas, caused by fast formation and growth of fine particles, has attracted much attention in recent years. In order to investigate the secondary formation and aging process of urban aerosols, four intensive campaigns were conducted in four seasons between March 2012 and March 2013 at an urban site in Beijing (116.31° E, 37.99° N). An Aerodyne high-resolution time-of-flight aerosol mass spectrometry (HR-ToF-AMS) was deployed to measure non-refractory chemical components of submicron particulate matter (NR-PM1). The average mass concentrations of PM1 (NR-PM1+black carbon) were 45.1 ± 45.8, 37.5 ± 31.0, 41.3 ± 42.7, and 81.7 ± 72.4 µg m-3 in spring, summer, autumn, and winter, respectively. Organic aerosol (OA) was the most abundant component in PM1, accounting for 31, 33, 44, and 36 % seasonally, and secondary inorganic aerosol (SNA, sum of sulfate, nitrate, and ammonium) accounted for 59, 57, 43, and 55 % of PM1 correspondingly. Based on the application of positive matrix factorization (PMF), the sources of OA were obtained, including the primary ones of hydrocarbon-like (HOA), cooking (COA), biomass burning OA (BBOA) and coal combustion OA (CCOA), and secondary component oxygenated OA (OOA). OOA, which can be split into more-oxidized (MO-OOA) and less-oxidized OOA (LO-OOA), accounted for 49, 69, 47, and 50 % in four seasons, respectively. Totally, the fraction of secondary components (OOA+SNA) contributed about 60-80 % to PM1, suggesting that secondary formation played an important role in the PM pollution in Beijing, and primary sources were also non-negligible. The evolution process of OA in different seasons was investigated with multiple metrics and tools. The average carbon oxidation states and other metrics show that the oxidation state of OA was the highest in summer, probably due to both strong photochemical and aqueous-phase oxidations. It was indicated by the good correlations

  16. Modeling the two-locus architecture of divergent pollinator adaptation: how variation in SAD paralogs affects fitness and evolutionary divergence in sexually deceptive orchids.

    Science.gov (United States)

    Xu, Shuqing; Schlüter, Philipp M

    2015-01-01

    Divergent selection by pollinators can bring about strong reproductive isolation via changes at few genes of large effect. This has recently been demonstrated in sexually deceptive orchids, where studies (1) quantified the strength of reproductive isolation in the field; (2) identified genes that appear to be causal for reproductive isolation; and (3) demonstrated selection by analysis of natural variation in gene sequence and expression. In a group of closely related Ophrys orchids, specific floral scent components, namely n-alkenes, are the key floral traits that control specific pollinator attraction by chemical mimicry of insect sex pheromones. The genetic basis of species-specific differences in alkene production mainly lies in two biosynthetic genes encoding stearoyl-acyl carrier protein desaturases (SAD) that are associated with floral scent variation and reproductive isolation between closely related species, and evolve under pollinator-mediated selection. However, the implications of this genetic architecture of key floral traits on the evolutionary processes of pollinator adaptation and speciation in this plant group remain unclear. Here, we expand on these recent findings to model scenarios of adaptive evolutionary change at SAD2 and SAD5, their effects on plant fitness (i.e., offspring number), and the dynamics of speciation. Our model suggests that the two-locus architecture of reproductive isolation allows for rapid sympatric speciation by pollinator shift; however, the likelihood of such pollinator-mediated speciation is asymmetric between the two orchid species O. sphegodes and O. exaltata due to different fitness effects of their predominant SAD2 and SAD5 alleles. Our study not only provides insight into pollinator adaptation and speciation mechanisms of sexually deceptive orchids but also demonstrates the power of applying a modeling approach to the study of pollinator-driven ecological speciation.

  17. The effect of different chemical compositions caused by the variation of deposition potential on properties of Ni-Co films

    Energy Technology Data Exchange (ETDEWEB)

    Karpuz, Ali, E-mail: alikarpuz@bau.edu.tr [Physics Department, Science and Literature Faculty, Balikesir University, Balikesir (Turkey); Kockar, Hakan [Physics Department, Science and Literature Faculty, Balikesir University, Balikesir (Turkey); Alper, Mursel [Physics Department, Science and Literature Faculty, Uludag University, Bursa (Turkey)

    2011-02-01

    The magnetic and microstructural properties of Ni-Co films electrodeposited at different cathode potentials were investigated. The compositional analysis revealed that the Ni content increases from 13 at.% to 44 at.% in the films with increasing deposition potential. Magnetic measurements showed that the saturation magnetization, M{sub s} of the films decreased with increase of Ni content as the deposition potential increased. M{sub s} values changed between 1160 emu/cm{sup 3} and 841 emu/cm{sup 3}. The X-ray diffraction revealed that the crystalline structure of the films is a mixture of the predominant face-centered cubic (fcc) and hexagonal closed packed. However, the mixture phase turns to the fcc because of increasing Ni content up to 44 at.% at the highest (-1.9 V) potential by enhancing the intensity of reflections from the fcc phase. The changes observed in the magnetic and microstructural properties were ascribed to the changes observed in the chemical composition caused by the applied different deposition potentials.

  18. Variation in some chemical parameters and organic matter in soils regenerated by the addition of municipal solid waste

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, C.; Hernandez, T.; Costa, F. (Centro de Edafologia y Biologia, Murcia (Spain))

    The organic fraction of a municipal solid waste was added in different doses to an eroded soil formed of loam and with no vegetal cover. After three years, the changes in macronutrient content and the chemical-structural composition of its organic matter were studied. The addition of the organic fraction from a municipal solid waste had a positive effect on soil regeneration, the treated soils being covered with spontaneous vegetation from 1 yr onwards. An increase in electrical conductivity and a fall in pH were noted in the treated soils as were increases in macronutrients, particularly N and available P and the different carbon fractions. Optical density measurements of the organic matter extracted with sodium pyrophosphate showed that the treated soils contained an organic matter with less condensed compounds and with a greater tendency to evolve than the control. A pyrolysis-gas chromatography study of the organic matter extracted with pyrophosphate showed large quantities of benzene both in the treated soils and control; pyrrole was also relatively abundant, although this fragment decreased as the dose rose. Xylenes and pyridine were present in greater quantities in the control and furfural in the treated soils.

  19. Chemical changes and carbon isotope variations in a cross-section of a large Miocene gymnospermous log

    Science.gov (United States)

    Bates, A.L.; Spiker, E. C.

    1992-01-01

    The cross-sectional radius of a 3-m (diam.) brown coal gymnospermous log of Miocene age, previously analyzed for carbohydrate and lignin methoxyl content by solid-state 13C nuclear magnetic resonance spectroscopy, was examined using stable carbon isotopic ratios in order to determine if the isotopic composition could be related to chemical changes or to radial position. This study found a possible relationship between ??13C-values and radial position; however, these changes cannot be linked to carbohydrate content and are probably attributable to changing growth conditions during the lifetime of the tree. An apparent linear relationship between the changes in carbohydrate content after sodium para-periodate treatment and corresponding changes in the ??13C-values indicates constant isotopic fractionation between lignin and carbohydrates along the cross-sectional radius. This result indicates that diagenesis has not produced any significant change in the lignin-carbohydrate carbon isotopic fractionation or, alternatively, that diagenesis has erased any fractionation pattern that once existed. A sample of fresh wood from another gymnospermous species was analyzed by the same methods and found to have lignin-carbohydrate carbon isotopic fractionation significantly different from that of the Miocene log section samples, suggesting that differences may be species-related or that the complex mixture of carbohydrates in the fresh wood was isotopically different from that of the degraded wood, and the whole Miocene log was uniformly altered. ?? 1992.

  20. Reproductive phenology of Creole horses in Ecuador in the absence of photoperiod variation: The effects of forage availability and flooding affecting body condition of mares.

    Science.gov (United States)

    Carranza, Juan; Yoong, Washington A; Mateos, Concha; Caño Vergara, Belén; Gómez, Chian L; Macías, Verónica

    2017-12-01

    Horse reproduction tends to be seasonal. The main adjusting factor in their original temperate ranges is photoperiod variation, although it is absent in equatorial areas where horses were introduced by European colonizers. Hence, dates of reproduction in these areas may be influenced by factors affecting mares' conditions and the success of foaling. Here we study reproductive timing in Creole horses in Ecuador reared in an extensive production system. We found that foaling peaked in August. Mares' conditions showed one peak in June-July, before the start of the breeding season, and another in December, and it was highly variable along the year. Mares' conditions increased after a period of vegetation growth and thus appeared negatively associated with the increment of grass greenness (normalized difference vegetation index data). Seasonal flooding of some pasturelands during March and April appeared to seriously impair mares' conditions and probably influenced the timing of foaling toward the dry season. Our results evidenced that horse breeding in these equatorial areas tended to be seasonal and point to some key factors that influence phenology by affecting body condition of mares, which may have implications for horse biology and management. © 2017 Japanese Society of Animal Science.

  1. The seasonal variation of the chemical composition of essential oils from Porcelia macrocarpa R.E. Fries (Annonaceae) and their antimicrobial activity.

    Science.gov (United States)

    da Silva, Erica Biolcati P; Soares, Marisi G; Mariane, Bruna; Vallim, Marcelo A; Pascon, Renata C; Sartorelli, Patricia; Lago, João Henrique G

    2013-11-01

    This study investigates the impact of seasonal variation on the chemical composition of essential oils from the leaves of Porcelia macrocarpa (Annonaceae) obtained over the course of one year (January-December 2011) and the chemical composition of the essential oils obtained from the ripe fruits of the same plant. Furthermore, the essential oils of the leaves were investigated with respect to their antimicrobial activity. The essential oils of the leaves contain a mixture of monoterpenes, one diterpene and several sesquiterpenes. The main components were identified as the sesquiterpenes germacrene D (29%-50%) and bicyclogermacrene (24%-37%). No significant variation was observed for the composition of the essential oil of the leaves over the course of the year, except for the month of November, when the ripe fruit were collected. In this month, substantially decreased concentrations of germacrene D (28.8 ± 0.8%) and bicyclogermacrene (23.9 ± 0.6%) were measured and the emergence of spathulenol (10.4 ± 0.2%) was observed. The essential oils extracted from the ripe fruit revealed the presence of a variety of monoterpenes, sesquiterpenes and hydrocarbons. The main constituents of these oils were neryl (8.8 ± 0.2%) and geranyl (27.3 ± 0.7%) formates, γ-muurolene (10.3 ± 0.9%) and dendrolasin (8.23 ± 0.06%). The antimicrobial activity of the essential oil obtained from the leaves of P. macrocarpa towards a range of bacterial and yeast strains was examined. In order to determine the minimum inhibitory concentration (MIC) of essential oils obtained from the January collection of the leaves, broth microdilution assays were carried out, which showed a significant antimicrobial activity towards Cryptococcus neoformans serotypes A and D as well as C. gattii serotypes B and C.

  2. Soil Chemical Properties and Nutrient Uptake of Cocoa as Affected by Application of Different Organic Matters and Phosphate Fertilizers

    OpenAIRE

    Sugiyanto, Sugiyanto; Bako Baon, John; Anom Wijaya, Ketut

    2008-01-01

    Effort repair of land quality better be done by simultan namely with application of organic matters and inorganic fertilization. The objective of this research is to study the effect of varied organic matters source and phosphate fertilizers on the chemicals soil characteristic and cocoa nutrient uptake. The experiment was laid experimentally in split-plot design and environmentally in randomized complete block design. The main plot was source of P consisted of, control, SP 36 and rock phosph...

  3. The Chemical Composition of Surface Waters of Technogenically Affected Geo-Systems in the Eastern Donbas Region

    Directory of Open Access Journals (Sweden)

    Olga S. Reshetnyak

    2014-11-01

    Full Text Available Based on an analysis of literary data and the author’s own research findings, the paper assesses the factors in the formation of the chemical composition of surface and subterranean waters and the variability of the chemical composition and quality of river waters in the eastern Donbas region. The author illustrates that the major negative effect of the impact of technogenic waters on river waters is salinization. The paper points up a high level of pollution in river waters with a broad spectrum of metal compounds, among which the biggest threat comes from Fegen, Al, Mn, Cu, and Sr, which is of a steady nature. The quality of water in the majority of rivers in the eastern Donbas region is evaluated as Quality Class 4 – dirty and/or very dirty. The findings can be used in resolving a whole array of scientific and applied objectives related to assessing the migration of chemical substances and the level of pollution in surface and subterranean waters and forecasting the condition of water sites and the quality of water, as well as in carrying out water-protection activities in the region.

  4. Detailed chemical abundances in NGC 5824: another metal-poor globular cluster with internal heavy element abundance variations

    Science.gov (United States)

    Roederer, Ian U.; Mateo, Mario; Bailey, John I.; Spencer, Meghin; Crane, Jeffrey D.; Shectman, Stephen A.

    2016-01-01

    We present radial velocities, stellar parameters, and detailed abundances of 39 elements derived from high-resolution spectroscopic observations of red giant stars in the luminous, metal-poor globular cluster NGC 5824. We observe 26 stars in NGC 5824 using the Michigan/Magellan Fiber System (M2FS) and two stars using the Magellan Inamori Kyocera Echelle spectrograph. We derive a mean metallicity of [Fe/H] = -1.94 ± 0.02 (statistical) ±0.10 (systematic). The metallicity dispersion of this sample of stars, 0.08 dex, is in agreement with previous work and does not exceed the expected observational errors. Previous work suggested an internal metallicity spread only when fainter samples of stars were considered, so we cannot exclude the possibility of an intrinsic metallicity dispersion in NGC 5824. The M2FS spectra reveal a large internal dispersion in [Mg/Fe], 0.28 dex, which is found in a few other luminous, metal-poor clusters. [Mg/Fe] is correlated with [O/Fe] and anticorrelated with [Na/Fe] and [Al/Fe]. There is no evidence for internal dispersion among the other α- or Fe-group abundance ratios. 25 of the 26 stars exhibit a n-capture enrichment pattern dominated by r-process nucleosynthesis ( = +0.11 ± 0.12; = -0.66 ± 0.05). Only one star shows evidence of substantial s-process enhancement ([Ba/Fe] = +0.56 ± 0.12; [Ba/Eu] = +0.38 ± 0.14), but this star does not exhibit other characteristics associated with s-process enhancement via mass transfer from a binary companion. The Pb and other heavy elements produced by the s-process suggest a time-scale of no more than a few hundred Myr for star formation and chemical enrichment, like the complex globular clusters M2, M22, and NGC 5286.

  5. Chemical Composition, Seasonal Variation and Size distribution of Atmospheric Aerosols at an Alpine Site in Guanzhong Plain, China

    Science.gov (United States)

    Li, J.

    2015-12-01

    PM10 and size-segregated aerosol samples were collected at Mt. Hua (2065 a.s.m) in central China, and determined for carbonaceous fraction, ions and organic composition. The concentration of most chemical compositions in summer are lower than those in winter, due to decreased emissions of biomass and coal burning for house heating. High temperature and relative humidity (RH) conditions are favorable for secondary aerosol formation, resulting in higher concentrations of SO42- and NH4+ in summer. Non-dehydrated sugars are increased in summer because of the enhanced metabolism. Carbon preference index results indicate that n-alkanes at Mt. Hua are derived mostly by plant wax. Low Benzo(a)pyrene/Benzo(a)pyrene ratios indicate that mountain aerosols are more aged. Concentrations of biogenic (BSOA, the isoprene/pinene/caryophyllene oxidation products) and anthropogenic (ASOA, mainly aromatic acids) SOA positively correlated with temperature . However, a decreasing trend of BSOA concentration with an increase in RH was observed during the sampling period, although a clear trend between ASOA and RH was not found. Based on the AIM Model calculation, we found that during the sampling period an increase in RH resulted in a decrease in the aerosol acidity and thus reduced the effect of acid-catalysis on BSOA formation. Size distributions of K+ and NH4+ present as an accumulation mode, in contrast to Ca2+ and Mg2+, which are mainly existed in coarse particles. SO42- and NO3- show a bimodal pattern. Dehydrated sugars, fossil fuel derived n-alkanes and PAHs presented unimode size distribution, whereas non-dehydrated sugars and plant wax derived n-alkanes showed bimodal pattern. Most of the determined BSOA are formed in the aerosol phase and enriched in the fine mode except for cis-pinonic acid, which is formed in the gas phase and subsequently partitioned into aerosol phase and thus presents a bimodal pattern with a major peak in the coarse mode.

  6. Variation patterns in individual fish responses to chemical stress among estuaries, seasons and genders: the case of the European flounder (Platichthys flesus) in the Bay of Biscay.

    Science.gov (United States)

    Laroche, Jean; Gauthier, Olivier; Quiniou, Louis; Devaux, Alain; Bony, Sylvie; Evrard, Estérine; Cachot, Jérôme; Chérel, Yan; Larcher, Thibaut; Riso, Ricardo; Pichereau, Vianney; Devier, Marie Hélène; Budzinski, Hélène

    2013-02-01

    The objective was to describe and model variation patterns in individual fish responses to contaminants among estuaries, season and gender. Two hundred twenty-seven adult European flounders were collected in two seasons (winter and summer) in four estuaries along the Bay of Biscay (South West France), focusing on a pristine system (the Ster), vs. three estuaries displaying contrasted levels of contaminants (the Vilaine, Loire and Gironde). Twenty-three variables were measured by fish, considering the load of contaminants (liver metals, liver and muscle persistent organic pollutants, muscle polycyclic aromatic hydrocarbons); the gene expression (Cyt C oxydase, ATPase, BHMT, Cyt P450 1A1, ferritin); the blood genotoxicity (Comet test); and liver histology (foci of cellular alteration-tumour, steatosis, inflammation, abnormal glycogen storage). Canonical redundancy analysis (RDA) was used to model these variables using gender, season and estuary of origin as explanatory variables. The results underlined the homogeneity of fish responses within the pristine site (Ster) and more important seasonal variability within the three contaminated systems. The complete model RDA was significant and explained 35 % of total variance. Estuary and season respectively explained 30 and 5 % of the total independent variation components, whilst gender was not a significant factor. The first axis of the RDA explains nearly 27 % of the total variance and mostly represents a gradient of contamination. The links between the load of contaminants, the expression of several genes and the biomarkers were analysed considering different levels of chemical stress and a possible multi-stress, particularly in the Vilaine estuary.

  7. Variation in essential oil composition within individual leaves of sweet basil (Ocimum basilicum L.) is more affected by leaf position than by leaf age.

    Science.gov (United States)

    Fischer, Ravit; Nitzan, Nadav; Chaimovitsh, David; Rubin, Baruch; Dudai, Nativ

    2011-05-11

    The aroma in sweet basil is a factor affecting the commercial value of the crop. In previous studies leaf age was considered to be a factor that influences the composition of essential oil (EO). In this study it was hypothesized that a single observation of the EO content in leaves from different positions on the main stem (young vs old) could predict the developmental changes in the plant during its life cycle. Plants harvested at week 16 demonstrated an exponential increase (R(2) = 0.92) in EO concentration in leaves on the main stem and lateral shoots, indicating higher EO concentrations in younger than in older leaves. Eugenol and methyleugenol predominated (28-77%) in the extract. Eugenol levels were higher in younger leaves (∼53%), and methyl-eugenol levels predominated in older leaves (∼68%). Linalool was lower in mature leaves than in younger leaves. This suggested that eugenol converted into methyleugenol and linalool decreased as leaf mature. However, in weekly monitored plants, the levels of these compounds in the EO had limited variation in the maturing leaf regardless of its position on the stem. This proposed that the EO composition in an individual leaf is mostly affected by the leaf position on the stem and not by its maturation process. Because leaf position is related to plant development, it is probable that the plant's physiological age at the time of leaf formation from the primordial tissue is the factor affecting the EO composition. It was concluded that interpretation of scientific observations should be carried out with caution and that hypotheses should be tested utilizing multifaceted approaches.

  8. [Study on the variation of arsenic concentration in groundwater and chemical characteristics of arsenic in sediment cores at the areas with endemic arsenic poison disease in Jianghan Plain].

    Science.gov (United States)

    Zhou, Suhua; Ye, Hengpeng; Li, Mingjian; Xiong, Peisheng; Du, Dongyun; Wang, Jingwen

    2015-06-01

    To understand the variation of arsenic concentration in underground water at the endemic arsenic poison disease area of Jianghan Plain so as to better understand the spatial distribution of high arsenic groundwater, hydro-chemical evolution and source of arsenic in this region. Thirty underground water samples were collected respectively around 3 km radius of the two houses where arsenic poisoning patients lived, in Xiantao and Honghu. Sediment cores of three drillings were collected as well. Both paired t-test or paired Wilcoxon Signed Ranking Test were used to compare the arsenic concentration of water. The arsenic concentration in 2011-2012 appeared lower than that in 2006-2007 at the Nanhong village of Xiantao (t = 4.645 3, P arsenic concentration and Cl, HCO3(-), Fe, Mn. However, negative correlations were found between As and SO4(2-), NO3(-). The range of arsenic content in the sediment was 1.500 mg/kg to 17.289 mg/kg. The maximum arsenic content existed in the soil layer, while the minimum arsenic content existed in the sand layer. The concentration of arsenic varied widely with time and space at endemic arsenic poison disease area of Jianghan Plain. Characteristics of these water chemicals showed significant differences, when compared to the groundwater from Datong Basin, Shanxi Shanyin and Hetao Plain of Inner Mongolia, which presented a typical environment with high arsenic contents in the groundwater. The arsenic content in the sediment samples seemed related to the lithologic structure.

  9. PM2.5in the Yangtze River Delta, China: Chemical compositions, seasonal variations, and regional pollution events.

    Science.gov (United States)

    Ming, Lili; Jin, Ling; Li, Jun; Fu, Pingqing; Yang, Wenyi; Liu, Di; Zhang, Gan; Wang, Zifa; Li, Xiangdong

    2017-04-01

    Fine particle (PM 2.5 ) samples were collected simultaneously at three urban sites (Shanghai, Nanjing, and Hangzhou) and one rural site near Ningbo in the Yangtze River Delta (YRD) region, China, on a weekly basis from September 2013 to August 2014. In addition, high-frequency daily sampling was conducted in Shanghai and Nanjing for one month during each season. Severe regional PM 2.5 pollution episodes were frequently observed in the YRD, with annual mean concentrations of 94.6 ± 55.9, 97.8 ± 40.5, 134 ± 54.3, and 94.0 ± 57.6 μg m -3 in Shanghai, Nanjing, Hangzhou, and Ningbo, respectively. The concentrations of PM 2.5 and ambient trace metals at the four sites showed clear seasonal trends, with higher concentrations in winter and lower concentrations in summer. In Shanghai, similar seasonal patterns were found for organic carbon (OC), elemental carbon (EC), and water-soluble inorganic ions (K + , NH 4 + , Cl - , NO 3 - , and SO 4 2- ). Air mass backward trajectory and potential source contribution function (PSCF) analyses implied that areas of central and northern China contributed significantly to the concentration and chemical compositions of PM 2.5 in Shanghai during winter. Three heavy pollution events in Shanghai were observed during autumn and winter. The modelling results of the Nested Air Quality Prediction Modeling System (NAQPMS) showed the sources and transport of PM 2.5 in the YRD during the three pollution processes. The contribution of secondary species (SOC, NH 4 + , NO 3 - , and SO 4 2- ) in pollution event (PE) periods was much higher than in BPE (before pollution event) and APE (after pollution event) periods, suggesting the importance of secondary aerosol formation during the three pollution events. Furthermore, the bioavailability of Cu, and Zn in the wintertime PM 2.5 samples from Shanghai was much higher during the pollution days than during the non-pollution days. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Seasonal variations in the chemical composition of particulate matter: a case study in the Po Valley. Part I: macro-components and mass closure.

    Science.gov (United States)

    Perrino, C; Catrambone, M; Dalla Torre, S; Rantica, E; Sargolini, T; Canepari, S

    2014-03-01

    The seasonal variability in the mass concentration and chemical composition of atmospheric particulate matter (PM10 and PM2.5) was studied during a 2-year field study carried out between 2010 and 2012. The site of the study was the area of Ferrara (Po Valley, Northern Italy), which is characterized by frequent episodes of very stable atmospheric conditions in winter. Chemical analyses carried out during the study allowed the determination of the main components of atmospheric PM (macro-elements, ions, elemental carbon, organic matter) and a satisfactory mass closure was obtained. Accordingly, chemical components could be grouped into the main macro-sources of PM: soil, sea spray, inorganic compounds from secondary reactions, vehicular emission, organics from domestic heating, organics from secondary formation, and other sources. The more significant seasonal variations were observed for secondary inorganic species in the fine fraction of PM; these species were very sensitive to air mass age and thus to the frequency of stable atmospheric conditions. During the winter ammonium nitrate, the single species with the highest concentration, reached concentrations as high as 30 μg/m(3). The intensity of natural sources was fairly constant during the year; increases in natural aerosols were linked to medium and long-range transport episodes. The ratio of winter to summer concentrations was roughly 2 for combustion product, close to 3 for secondary inorganic species, and between 2 and 3 for organics. The winter increase of organics was due to poorer atmospheric dispersion and to the addition of the emission from domestic heating. A similar winter to summer ratio (around 3) was observed for the fine fraction of PM.

  11. Geological factors affecting the chemical characteristics of the thermal waters of the carbonate karstified aquifers of Northern Vietnam

    Directory of Open Access Journals (Sweden)

    C. Drogue

    2000-01-01

    Full Text Available In northern Vietnam, exposed carbonate rock formations cover an area of more than 50,000 km2 .Their accumulated thickness from the Cambrian to the Triassic is in some places as much as 3000 m. Numerous thermal waters (springs and wells occur in these strongly karstified carbonate massifs. This is the result of significant ancient and present orogenic activity, as the region demonstrates by its strong seismic activity. These karstic formations are water-bearing and strongly recharged by rainfall of between 1600 mm and 2000 mm per year in 90% of the area concerned. In view of the average annual air temperatures (17°C-25°C according to the region, 23 sample springs or wells were chosen with water temperatures of between 29°C and 68°C. Hydrochemical characteristics of these thermal waters emerging in different carbonate-rock units were examined by chemical analyses of major ions. In this large region, thermal waters are divided into four hydrochemical types: the Na-Cl type resulting from the intrusion of sea water for distances of up to several kilometres inland and depths of 1000 m, the Ca-SO4 type, probably resulting from the leaching of deposits of metallic sulphides that are widely distributed in these carbonate-rock units, and finally the Ca-HCO3 and Mg-HCO3 types which are chemically similar to fresh karstic waters in limestones and dolostones. The occurrence of these thermal groundwaters as well as their chemical characteristics seem to indicate the existence of large-scale deepseated groundwater flow systems in the karstic aquifers. Keywords: Vietnam; thermal waters; karst; hydrochemistry

  12. Shelf life of fresh-cut spinach as affected by chemical treatment and type of packaging film

    Directory of Open Access Journals (Sweden)

    A.M. Piagentini

    2002-12-01

    Full Text Available Fresh-cut vegetables are an important and rapidly developing class of convenience foods. Their storage life may be greatly reduced due to their high rates of respiration and transpiration and the possibility of enzymatic and microbiological deterioration. Consequently, the objective of this work was to determine the shelf life and the failure attribute that conditioned the shelf life of fresh-cut spinach treated with chemical solutions and packaged in bags with different permeabilities. The shelf life of fresh-cut vegetables was defined as the time of refrigerated storage at which any one of the sensory attributes scored below 7 or when the microbiological counts exceeded 5.10(7 CFU/g. Fresh-cut spinach was treated with citric acid and ascorbic acid solutions and packaged in mono-oriented polypropylene (OPP bags or low-density polyethylene (LDPE bags. Sensory attributes and total microbial counts were evaluated throughout refrigerated storage. Response surface methodology (RSM was used to study the simultaneous effect of chemical treatment and refrigerated storage time on sensory and microbiological quality of fresh-cut spinach. A quadratic polynomial regression model was assumed for predicting off-odor, general appearance, wilting, browning, color, and mesophilic aerobic population. Type of packaging film only influenced development of off-odor (p£0.001 and had no effect on visual sensory attributes or microbiological counts (p>0.05. Development of off-odor was the attribute that limited shelf life of fresh-cut spinach packaged in OPP bags. On the other hand, shelf life of samples packaged in LDPE bags was dependent on a decrease in general appearance or an increase in microbiological counts, depending on the chemical treatment used.

  13. The Rules of Aggression: How Genetic, Chemical and Spatial Factors Affect Intercolony Fights in a Dominant Species, the Mediterranean Acrobat Ant Crematogaster scutellaris.

    Directory of Open Access Journals (Sweden)

    Filippo Frizzi

    Full Text Available Nest-mate recognition plays a key role in the biology of ants. Although individuals coming from a foreign nest are, in most cases, promptly rejected, the degree of aggressiveness towards non nest-mates may be highly variable among species and relies on genetic, chemical and environmental factors. We analyzed intraspecific relationships among neighboring colonies of the dominant Mediterranean acrobat ant Crematogaster scutellaris integrating genetic, chemical and behavioral analyses. Colony structure, parental relationships between nests, cuticular hydrocarbons profiles (CHCs and aggressive behavior against non nest-mates were studied in 34 nests located in olive tree trunks. Bayesian clustering analysis of allelic variation at nine species-specific microsatellite DNA markers pooled nests into 14 distinct clusters, each representing a single colony, confirming a polydomous arrangement of nests in this species. A marked genetic separation among colonies was also detected, probably due to long distance dispersion of queens and males during nuptial flights. CHCs profiles varied significantly among colonies and between nests of the same colony. No relationship between CHCs profiles and genetic distances was detected. The level of aggressiveness between colonies was inversely related to chemical and spatial distance, suggesting a 'nasty neighbor' effect. Our findings also suggest that CHCs profiles in C. scutellaris may be linked to external environmental factors rather than genetic relationships.

  14. Subspecies and diet affect the expression of genes involved in lipid metabolism and chemical composition of muscle in beef cattle.

    Science.gov (United States)

    Teixeira, Priscilla D; Oliveira, Dalton M; Chizzotti, Mario L; Chalfun-Junior, Antonio; Coelho, Tamara C; Gionbelli, MateusP; Paiva, Luciano V; Carvalho, José Roberto R; Ladeira, Marcio M

    2017-11-01

    Fourteen Nellore and 14 Angus young bulls with BW of 381±11.8kg were randomly assigned into 2 feeding groups (whole shelled corn without forage (WSC) or corn silage and ground corn (GC)) to evaluate chemical composition and expression of genes involved in lipid metabolism in the longissimus thoracis (LT). We hypothesized that bulls fed the WSC diet have greater amounts of intramuscular fat and Angus have higher expression levels of PPAR and SREBF. Meat from Angus bulls had greater ether extract compared to Nellore (Pbeef of bulls fed this diet due to the reduced expression of SREBF1. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Biological and Chemical Removal of Primary Cilia Affects Mechanical Activation of Chondrogenesis Markers in Chondroprogenitors and Hypertrophic Chondrocytes

    Directory of Open Access Journals (Sweden)

    Matthew E. Deren

    2016-02-01

    Full Text Available Chondroprogenitors and hypertrophic chondrocytes, which are the first and last stages of the chondrocyte differentiation process, respectively, are sensitive to mechanical signals. We hypothesize that the mechanical sensitivity of these cells depends on the cell surface primary cilia. To test this hypothesis, we removed the primary cilia by biological means with transfection with intraflagellar transport protein 88 (IFT88 siRNA or by chemical means with chloral hydrate treatment. Transfection of IFT88 siRNA significantly reduced the percentage of ciliated cells in both chondroprogenitor ATDC5 cells as well as primary hypertrophic chondrocytes. Cyclic loading (1 Hz, 10% matrix deformation of ATDC5 cells in three-dimensional (3D culture stimulates the mRNA levels of chondrogenesis marker Type II collagen (Col II, hypertrophic chondrocyte marker Type X collagen (Col X, and a molecular regulator of chondrogenesis and chondrocyte hypertrophy bone morphogenetic protein 2 (BMP-2. The reduction of ciliated chondroprogenitors abolishes mechanical stimulation of Col II, Col X, and BMP-2. In contrast, cyclic loading stimulates Col X mRNA levels in hypertrophic chondrocytes, but not those of Col II and BMP-2. Both biological and chemical reduction of ciliated hypertrophic chondrocytes reduced but failed to abolish mechanical stimulation of Col X mRNA levels. Thus, primary cilia play a major role in mechanical stimulation of chondrogenesis and chondrocyte hypertrophy in chondroprogenitor cells and at least a partial role in hypertrophic chondrocytes.

  16. Mechanical and chemical processes affecting the chalk during burial, insights from combined reflection seismics, well data and field work

    DEFF Research Database (Denmark)

    Moreau, Julien; Boussaha, Myriam; Thibault, Nicolas Rudolph

    2014-01-01

    and cores analyses, respectively.However, few sites allow to combine all the different scale of observation for chalk diagenesis. Onshore and offshore high resolution seismics, two fully cored >350 m wells with wireline logging tools and very high quality exposures from a coastal cliff and a quarry form......The chalk must undergo several phases of grain reorganisation and chemical reactions during its diagenetic evolution from a carbonaceous ooze to a sedimentary rock. Some of these transformations could be observed on structures from the kilometre- to the micrometre-scale with seismic reflection....... The pressure-solution allows the formation of carbonate seams in the hairline fractures. At larger scale, on the field are observed faults which are sealed with flint precipitations. They slightly offset (seismic reflection profiles, numerous...

  17. Circadian variation of cardiac autonomic nervous profile is affected in Japanese ambulance men with a working system of 24-h shifts.

    Science.gov (United States)

    Mitani, Satoko; Fujita, Masatoshi; Shirakawa, Taro

    2006-01-01

    The purpose of this study was to compare the stress levels of Japanese ambulance men between on-duty and off-duty days, by using the physiological indices of heart rate variability (HRV) and cortisol in urine, measured over each 24-h period. Measurements were made during one on-duty and one off-duty day for each subject. The participants were monitored for 24 h with a Holter recording system and a parameter reflecting overall stress levels was obtained by measuring the cortisol level in urine collected over 24 h. The circadian variation of cardiac autonomic nervous system activity was affected when the subjects were on duty. The low-frequency/high-frequency power ratio (=low-frequency power/high-frequency power: LF/HF), which is a useful parameter that reflects the balance of cardiac autonomic nervous activity, differed significantly between the waking and sleeping times on the off-duty day (P=0.03), while it did not differ between these two states on the on-duty day (P=0.56). Similarly, the normalized high-frequency power [=high-frequency/(high-frequency+low-frequency) power: HF/(HF+LF)] ratio, which is a useful measure of the activity of the parasympathetic nervous system, differed significantly between these two states on the off-duty day (P=0.04), while there was no significant difference in the ratio between the two states on the on-duty day (P=0.13). These results show that the diurnal balance of the cardiac autonomic nervous system is affected on the on-duty day, even though it is possible for ambulance men to sleep regular hours.

  18. Factors Affecting Temporal and Spatial Variations of Microcystins in Gonghu Bay of Lake Taihu, with Potential Risk of Microcystin Contamination to Human Health

    Directory of Open Access Journals (Sweden)

    Qing Wang

    2010-01-01

    Full Text Available A field survey of the seasonal variation of microcystin (MC concentration was performed in Gonghu Bay (a total of 15 sampling sites of Lake Taihu from January to December 2008. Microcystis spp. biomass and intra-/extracellular MCs were significantly correlated with water temperature, suggesting the importance of temperature in cyanobacterial blooming in the lake. Higher MC concentration was found in summer and autumn, and peaks of Microcystis biomass and intra-/extracellular MC concentrations were all present in October. Spatially, risk of MCs was higher in littoral zones than in the pelagic area. There were significant correlations between N or P concentrations, and Microcystis biomass or MC content, suggesting that N and P levels affected MC production through influencing Microcystis biomass. Intra-/extracellular MCs and Microcystis biomass had negative exponential relationships with TN:TP, and the maximum values all occurred when TN:TP was <25. Multivariate analyses by pcca indicated that intra- and extracellular MC concentrations had better correlations with biological factors (such as Microcystis biomass and chl-a than physicochemical factors. The maximum concentration reached up to 17 µg/L MC-Lreq, considerably higher drinking water safety standard (1 µg/L recommended who. So it is necessary take measures reduce exposure risk of cyanobacterial toxins human beings.

  19. Iron biofortification of wheat grains through integrated use of organic and chemical fertilizers in pH affected calcareous soil.

    Science.gov (United States)

    Ramzani, Pia Muhammad Adnan; Khalid, Muhammad; Naveed, Muhammad; Ahmad, Rashid; Shahid, Muhammad

    2016-07-01

    Incidence of iron (Fe) deficiency in human populations is an emerging global challenge. This study was conducted to evaluate the potential of iron sulphate combined with biochar and poultry manure for Fe biofortification of wheat grains in pH affected calcareous soil. In first two incubation studies, rates of sulfur (S) and Fe combined with various organic amendments for lowering pH and Fe availability in calcareous soil were optimized. In pot experiment, best rate of Fe along with biochar (BC) and poultry manure (PM) was evaluated for Fe biofortification of wheat in normal and S treated low pH calcareous soil. Fe applied with BC provided fair increase in root-shoot biomass and photosynthesis up to 79, 53 and 67%, respectively in S treated low pH soil than control. Grain Fe and ferritin concentration was increased up to 1.4 and 1.2 fold, respectively while phytate and polyphenol was decreased 35 and 44%, respectively than control in treatment where Fe was applied with BC and S. In conclusion, combined use of Fe and BC could be an effective approach to improve growth and grain Fe biofortification of wheat in pH affected calcareous soil. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  20. Physico-chemical, rheological and antioxidant properties of sweet chestnut (Castanea sativa Mill.) as affected by pan and microwave roasting.

    Science.gov (United States)

    Wani, Idrees Ahmed; Hamid, Humaira; Hamdani, Afshan Mumtaz; Gani, Adil; Ashwar, Bilal Ahmad

    2017-07-01

    Sweet chestnut ( Castanea sativa Mill. ) belongs to the family Fagaceae and sub family Castaneoideae. Bioactive components such as tannins are present in sweet chestnut in high proportion giving astringent bitter taste and reducing their palatability. Roasting reduces the anti-nutritional factors in chestnut. This study was conducted to compare the effects of pan and microwave roasting on physicochemical, functional, rheological and antioxidant properties of sweet chestnut. Antioxidant activity was determined using DPPH inhibition activity, reducing power, and total phenolic content. Structural analysis was carried out using FT-IR analysis. Protein, fat, and ash contents displayed insignificant ( P  > 0.05) variations. " L " value decreased from 90.66 to 81.43, whereas, " a " and " b " values increased from 0.02 to 0.90 and 11.99 to 20.5, respectively, upon roasting. Significant ( P  < 0.05) increase in water absorption capacity (1.32-3.39 g/g), oil absorption capacity (1.22-1.63 g/g), and antioxidant properties was observed following roasting. Flour obtained from roasted chestnuts exhibited a significant decrease in light transmittance, foaming, and pasting properties. Higher gelatinization temperatures and lower enthalpies were reported in microwave and pan roasted chestnut flours. Roasting also reduced the viscoelastic behavior of native sweet chestnut and changed the transmittance of identical functional groups as revealed by FT-IR analysis.

  1. Variation of Chemical Composition in Flowers and Leaves Essential Oils Among Natural Population of Tunisian Glebionis coronaria (L.) Tzvelev (Asteraceae).

    Science.gov (United States)

    Haouas, Dalila; Cioni, Pier Luigi; Flamini, Guido; Ben Halima-Kamel, Monia; Ben Hamouda, Mohamed Habib

    2016-10-01

    The aim of this study was to assess the percentage and constituents variations in flowers and leaves essential oil of three Glebionis coronaria (L.) Tzvelev population, growing wildly in three different ecotypes (Utique, M'saken, and Sahara Lektar) in Tunisia. The chemical compositions of these essential oils were analyzed by the GC and GC/MS systems. Qualitative and quantitative differences were recorded between essential oils extracted from plants collected from the three geographical provinces and between organs of the same plant (leaves and flowers). In fact, 161 components representing 87.2 - 96.5% of the whole oils were identified. Myrcene (3.2 - 35.7%), (Z)-β-ocimene (0.6 - 23.0%), camphor (0.6 - 17.2%), cis-chrysanthenol (0 - 6.9%), cis-chrysanthenyl acetate (1.1 - 17.9%), isobornyl acetate (1.6 - 3.5%), (E)-β-farnesene (0 - 6.0%), germacrene D (0 - 8.7%), and (E,E)-α-farnesene (0.7 - 12.4%) were the predominant components in the oils. These major constituents occur in different amounts depending on the organs (leaves or flowers) and the geographical origin of the plant. The chemotaxonomic usefulness of these data was discussed according to results of principal component analysis (PCA). The scores, together with the loadings, revealed a different chemical pattern for each population. © 2016 Wiley-VHCA AG, Zürich.

  2. Fungal endophytes of Alpinia officinarum rhizomes: insights on diversity and variation across growth years, growth sites, and the inner active chemical concentration.

    Directory of Open Access Journals (Sweden)

    Li Shubin

    Full Text Available In the present study, the terminal-restriction fragment length polymorphism (T-RFLP technique, combined with the use of a clone library, was applied to assess the baseline diversity of fungal endophyte communities associated with rhizomes of Alpinia officinarum Hance, a medicinal plant with a long history of use. A total of 46 distinct T-RFLP fragment peaks were detected using HhaI or MspI mono-digestion-targeted, amplified fungal rDNA ITS sequences from A. officinarum rhizomes. Cloning and sequencing of representative sequences resulted in the detection of members of 10 fungal genera: Pestalotiopsis, Sebacina, Penicillium, Marasmius, Fusarium, Exserohilum, Mycoleptodiscus, Colletotrichum, Meyerozyma, and Scopulariopsis. The T-RFLP profiles revealed an influence of growth year of the host plant on fungal endophyte communities in rhizomes of this plant species; whereas, the geographic location where A. officinarum was grown contributed to only limited variation in the fungal endophyte communities of the host tissue. Furthermore, non-metric multidimensional scaling (NMDS analysis across all of the rhizome samples showed that the fungal endophyte community assemblages in the rhizome samples could be grouped according to the presence of two types of active indicator chemicals: total volatile oils and galangin. Our present results, for the first time, address a diverse fungal endophyte community is able to internally colonize the rhizome tissue of A. officinarum. The diversity of the fungal endophytes found in the A. officinarum rhizome appeared to be closely correlated with the accumulation of active chemicals in the host plant tissue. The present study also provides the first systematic overview of the fungal endophyte communities in plant rhizome tissue using a culture-independent method.

  3. Comparative studies on chemical parameters and antioxidant properties of stipes and caps of shiitake mushroom as affected by different drying methods.

    Science.gov (United States)

    Zhang, Ning; Chen, Haixia; Zhang, Yu; Ma, Lishuai; Xu, Xufeng

    2013-09-01

    Shiitake, the second most cultivated mushroom, is famous for its high nutritional value and medicinal properties. In this study, various chemical parameters and antioxidant properties of caps and stipes of shiitake mushroom dried by different methods (freeze-drying, shade drying and hot air drying) were comparatively investigated by spectrophotometric assays, high-performance liquid chromatography, 1,1'-diphenyl-2-picrylhydrazyl assay, ferric reducing power assay and lipid peroxidation inhibition assay. The contents of amino acids, neutral sugar and total phenolics in stipes were higher than those in caps of shiitake, while caps showed advantages in terms of their contents of protein and eritadenine. The chemical parameters and antioxidant activities of shiitake were significantly affected by the drying method used. The contents of total phenolics, amino acids and neutral sugar in stipes were higher than those in caps of shiitake, which suggested that stipes were more nutritional than caps in some respects. Hot air drying at 50 °C resulted in high total phenolic, amino acid, uronic acid and neutral sugar contents and antioxidant activities, which could be useful for the application of shiitake and related products in the food industry. © 2013 Society of Chemical Industry.

  4. Small Variations in Early-Life Environment Can Affect Coping Behaviour in Response to Foraging Challenge in the Three-Spined Stickleback.

    Science.gov (United States)

    Langenhof, M Rohaa; Apperloo, Rienk; Komdeur, Jan

    2016-01-01

    An increasing concern in the face of human expansion throughout natural habitats is whether animal populations can respond adaptively when confronted with challenges like environmental change and novelty. Behavioural flexibility is an important factor in estimating the adaptive potential of both individuals and populations, and predicting the degree to which they can cope with change. This study on the three-spined stickleback (Gasterosteus aculeatus) is an empiric illustration of the degree of behavioural variation that can emerge between semi-natural systems within only a single generation. Wild-caught adult sticklebacks (P, N = 400) were randomly distributed in equal densities over 20 standardized semi-natural environments (ponds), and one year later offspring (F1, N = 652) were presented with repeated behavioural assays. Individuals were challenged to reach a food source through a novel transparent obstacle, during which exploration, activity, foraging, sociability and wall-biting behaviours were recorded through video observation. We found that coping responses of individuals from the first generation to this unfamiliar foraging challenge were related to even relatively small, naturally diversified variation in developmental environment. All measured behaviours were correlated with each other. Especially exploration, sociability and wall-biting were found to differ significantly between ponds. These differences could not be explained by stickleback density or the turbidity of the water. Our findings show that a) differences in early-life environment appear to affect stickleback feeding behaviour later in life; b) this is the case even when the environmental differences are only small, within natural parameters and diversified gradually; and c) effects are present despite semi-natural conditions that fluctuate during the year. Therefore, in behaviourally plastic animals like the stickleback, the adaptive response to human-induced habitat disturbance may occur

  5. Small Variations in Early-Life Environment Can Affect Coping Behaviour in Response to Foraging Challenge in the Three-Spined Stickleback.

    Directory of Open Access Journals (Sweden)

    M Rohaa Langenhof

    Full Text Available An increasing concern in the face of human expansion throughout natural habitats is whether animal populations can respond adaptively when confronted with challenges like environmental change and novelty. Behavioural flexibility is an important factor in estimating the adaptive potential of both individuals and populations, and predicting the degree to which they can cope with change.This study on the three-spined stickleback (Gasterosteus aculeatus is an empiric illustration of the degree of behavioural variation that can emerge between semi-natural systems within only a single generation. Wild-caught adult sticklebacks (P, N = 400 were randomly distributed in equal densities over 20 standardized semi-natural environments (ponds, and one year later offspring (F1, N = 652 were presented with repeated behavioural assays. Individuals were challenged to reach a food source through a novel transparent obstacle, during which exploration, activity, foraging, sociability and wall-biting behaviours were recorded through video observation. We found that coping responses of individuals from the first generation to this unfamiliar foraging challenge were related to even relatively small, naturally diversified variation in developmental environment. All measured behaviours were correlated with each other. Especially exploration, sociability and wall-biting were found to differ significantly between ponds. These differences could not be explained by stickleback density or the turbidity of the water.Our findings show that a differences in early-life environment appear to affect stickleback feeding behaviour later in life; b this is the case even when the environmental differences are only small, within natural parameters and diversified gradually; and c effects are present despite semi-natural conditions that fluctuate during the year. Therefore, in behaviourally plastic animals like the stickleback, the adaptive response to human-induced habitat disturbance

  6. [Accumulation Characteristics and Evaluation of Heavy Metals in Soil-Crop System Affected by Wastewater Irrigation Around a Chemical Factory in Shenmu County].

    Science.gov (United States)

    Qi, Yan-bing; Chu, Wan-lin; Pu, Jie; Liu, Meng-yun; Chang, Qing-rui

    2015-04-01

    Soil heavy metals Cu, Pb, Zn, and Cd, are regarded as "chemical time bombs" because of their propensity for accumulation in the soil and uptake by crops. This ultimately causes human toxicity in both the short and long-term, making farmland ecosystems dangerous to health. In this paper, accumulation and spatial variability of Cu, Zn, Pb and Cd in soil-crop system affected by wastewater irrigation around a chemical factor in northern Shaanxi province were analyzed. Results showed that wastewater irrigation around the chemical factory induced significant accumulation in soils compared with control areas. The average concentrations of available Cu and total Cu were 4.32 mg x kg(-1) and 38.4 mg x kg(-1), which were twice and 1.35 times higher than those of the control area, respectively. Soil Zn and Pb were slightly accumulated. Whereas soil Cd was significantly accumulated and was higher than the critical level of soil environmental quality (II), the available and total Cd concentrations were 0.248 mg x kg(-1) and 1.21 mg x kg(-1), which were 10 and 6.1 times higher than those of the control areas. No significant correlations were found between available and total heavy metals except between available Cd and total Cd. All the heavy metals were mainly accumulated in the top layer (0-10 cm). Spatially, soils and plants high in heavy metal concentration were distributed within the radius of about 100 m from the waste water outlet for Cu, Zn and Cd and about 200 m for Pb, and decreased exponentially with the distance from the factory. Affected by wastewater irrigation, contents of Cu, Pb and Cd in maize were 4.74, 0.129 and 0.036 mg x kg(-1) which were slightly higher than those in the control area. The content of Zn was similar to that in the control area. Affected by the vehicle exhaust, the over standard rate of Pb was 5.7% in maize. All the heavy metals did not show significant correlation between soil and crop, except Cd. The square correlation coefficients were 0

  7. Variations in the chemical composition of lamprophyllite-group minerals and the crystal structure of fluorine-rich barytolamprophyllite from new peralkaline dyke

    Science.gov (United States)

    Akimenko, M. I.; Aksenov, S. M.; Sorokhtina, N. V.; Kogarko, L. N.; Kononkova, N. N.; Rastsvetaeva, R. K.; Rozenberg, K. A.

    2015-11-01

    The variations in the chemical composition of lamprophyllite-group minerals from a peralkaline dyke of the Mokhnatye Roga area (Kandalaksha region, Kola Peninsula), which are crystallized during the entire period of dyke formation and form several generations, have been investigated. The early generations differ in a steadily high fluorine content, while the later ones exhibit reduced amount of fluorine, impurity elements, and sodium, with a simultaneous increase in the potassium content. The crystal structure of fluorine- rich barytolamprophyllite (potentially a new representative of the lamprophyllite group, differing by the predominance of fluorine in the anion X site) has been analyzed by single crystal X-ray diffraction. This mineral is found to have a monoclinic unit cell with the following parameters: a = 19.5219(8) Å, b = 7.0915(2) Å, c = 5.3925(2) Å, β = 96.628(3)°, and sp. gr. C2/ m. The structure is refined to R = 5.73% in the anisotropic approximation of the atomic displacement parameters using 3668 I > 2σ( I). The idealized formula ( Z = 2) is (Ba,Sr)2[Na(Na,Fe)2(Ti,Mg)F2][Ti2(Si2O7)2O2].

  8. Natural variations in snow cover do not affect the annual soil CO2 efflux from a mid-elevation temperate forest.

    Science.gov (United States)

    Schindlbacher, Andreas; Jandl, Robert; Schindlbacher, Sabine

    2014-02-01

    Climate change might alter annual snowfall patterns and modify the duration and magnitude of snow cover in temperate regions with resultant impacts on soil microclimate and soil CO2 efflux (Fsoil ). We used a 5-year time series of Fsoil measurements from a mid-elevation forest to assess the effects of naturally changing snow cover. Snow cover varied considerably in duration (105-154 days) and depth (mean snow depth 19-59 cm). Periodically shallow snow cover (effects of slowly changing soil temperatures and determined the overall course of Fsoil . Cumulative CO2 efflux from beneath snow cover varied between 0.46 and 0.95 t C ha(-1)  yr(-1) and amounted to between 6 and 12% of the annual efflux. When compared over a fixed interval (the longest period of snow cover during the 5 years), the cumulative CO2 efflux ranged between 0.77 and 1.18 t C ha(-1) or between 11 and 15% of the annual soil CO2 efflux. The relative contribution (15%) was highest during the year with the shortest winter. Variations in snow cover were not reflected in the annual CO2 efflux (7.44-8.41 t C ha(-1) ) which did not differ significantly between years and did not correlate with any snow parameter. Regional climate at our site was characterized by relatively high amounts of precipitation. Therefore, snow did not play a role in terms of water supply during the warm season and primarily affected cold season processes. The role of changing snow cover therefore seems rather marginal when compared to potential climate change effects on Fsoil during the warm season. © 2013 The Authors. Global Change Biology published by John Wiley & Sons Ltd.

  9. Between and within-field variation in physico-chemical soil properties of vineyards: implications for terroir zoning and management in Heuvelland, Belgium

    Science.gov (United States)

    Tavernier, Emma; Verdoodt, Ann; Cornelis, Wim; Delbecque, Nele; Tiebergijn, Lynn; Seynnaeve, Marleen; Gabriels, Donald

    2015-04-01

    The 'Heuvelland' region with a surface area of 94 km² is situated in the Province of West Flanders, Belgium, bordering with France. The region comprises a number of hills ("heuvel") on which a fast growing 'wine culture' is developing. Both professional as well as non-professional wine makers together cultivate about 19 ha of vineyards, and are still expanding. Grapes cultivated include Chardonnay, Pinot gris and Pinot noir among others. The small-scale, strongly dispersed vineyards are located in different landscape positions of variable aspect. The objective of our preliminary study was to assess the between-field and within-field variation in physico-chemical soil properties of these vineyards with the aim to better characterise the terroir(s) in Heuvelland and provide guidelines for soil management. Fourteen vineyards from five different wineries were selected for detailed soil sampling. Twenty-five sampling sites were chosen according to the topography, soil map units and observed variability in grape growth. The soil was sampled using 15 cm depth increments up to a depth of 60 cm or a shallower lithic contact. Composite samples of 5 sampling locations along the contour lines were taken per within-field zone. Besides the texture, pH, organic carbon, total nitrogen, available phosphorous and exchangeable base cations (Ca, Mg, K), also some micronutrients (Fe, B, Cu, Mn) were determined using standard laboratory procedures. The soils developed on Quaternary niveo-eolian sandy loam and loamy sediments of variable thickness covering marine sandy and clayey sediments of the Tertiary. Where the Tertiary clayey sediments occur at shallow depth, they can strongly influence the internal drainage. At higher positions in the landscape, iron-rich sandstone layers are found at shallow depth. Fragments of this iron-rich sandstone can also be found at lower positions (colluvial material). This iron sandstone is claimed to contribute to the unique character of this wine

  10. Variation in tree mortality and regeneration affect forest carbon recovery following fuel treatments and wildfire in the Lake Tahoe Basin, California, USA.

    Science.gov (United States)

    Carlson, Chris H; Dobrowski, Solomon Z; Safford, Hugh D

    2012-06-28

    Forest fuel treatments have been proposed as tools to stabilize carbon stocks in fire-prone forests in the Western U.S.A. Although fuel treatments such as thinning and burning are known to immediately reduce forest carbon stocks, there are suggestions that these losses may be paid back over the long-term if treatments sufficiently reduce future wildfire severity, or prevent deforestation. Although fire severity and post-fire tree regeneration have been indicated as important influences on long-term carbon dynamics, it remains unclear how natural variability in these processes might affect the ability of fuel treatments to protect forest carbon resources. We surveyed a wildfire where fuel treatments were put in place before fire and estimated the short-term impact of treatment and wildfire on aboveground carbon stocks at our study site. We then used a common vegetation growth simulator in conjunction with sensitivity analysis techniques to assess how predicted timescales of carbon recovery after fire are sensitive to variation in rates of fire-related tree mortality, and post-fire tree regeneration. We found that fuel reduction treatments were successful at ameliorating fire severity at our study site by removing an estimated 36% of aboveground biomass. Treated and untreated stands stored similar amounts of carbon three years after wildfire, but differences in fire severity were such that untreated stands maintained only 7% of aboveground carbon as live trees, versus 51% in treated stands. Over the long-term, our simulations suggest that treated stands in our study area will recover baseline carbon storage 10-35 years more quickly than untreated stands. Our sensitivity analysis found that rates of fire-related tree mortality strongly influence estimates of post-fire carbon recovery. Rates of regeneration were less influential on recovery timing, except when fire severity was high. Our ability to predict the response of forest carbon resources to anthropogenic and

  11. Variation in tree mortality and regeneration affect forest carbon recovery following fuel treatments and wildfire in the Lake Tahoe Basin, California, USA

    Directory of Open Access Journals (Sweden)

    Carlson Chris H

    2012-06-01

    Full Text Available Abstract Background Forest fuel treatments have been proposed as tools to stabilize carbon stocks in fire-prone forests in the Western U.S.A. Although fuel treatments such as thinning and burning are known to immediately reduce forest carbon stocks, there are suggestions that these losses may be paid back over the long-term if treatments sufficiently reduce future wildfire severity, or prevent deforestation. Although fire severity and post-fire tree regeneration have been indicated as important influences on long-term carbon dynamics, it remains unclear how natural variability in these processes might affect the ability of fuel treatments to protect forest carbon resources. We surveyed a wildfire where fuel treatments were put in place before fire and estimated the short-term impact of treatment and wildfire on aboveground carbon stocks at our study site. We then used a common vegetation growth simulator in conjunction with sensitivity analysis techniques to assess how predicted timescales of carbon recovery after fire are sensitive to variation in rates of fire-related tree mortality, and post-fire tree regeneration. Results We found that fuel reduction treatments were successful at ameliorating fire severity at our study site by removing an estimated 36% of aboveground biomass. Treated and untreated stands stored similar amounts of carbon three years after wildfire, but differences in fire severity were such that untreated stands maintained only 7% of aboveground carbon as live trees, versus 51% in treated stands. Over the long-term, our simulations suggest that treated stands in our study area will recover baseline carbon storage 10–35 years more quickly than untreated stands. Our sensitivity analysis found that rates of fire-related tree mortality strongly influence estimates of post-fire carbon recovery. Rates of regeneration were less influential on recovery timing, except when fire severity was high. Conclusions Our ability to predict

  12. Modifications of the chemical structure of phenolics differentially affect physiological activities in pulvinar cells of Mimosa pudica L. I. Multimode effect on early membrane events.

    Science.gov (United States)

    Rocher, Françoise; Dédaldéchamp, Fabienne; Saeedi, Saed; Fleurat-Lessard, Pierrette; Chollet, Jean-Francois; Roblin, Gabriel

    2014-11-01

    A study of the structure-activity relationship carried out on several benzoic acid-related phenolics indicates that this type of compounds hinders the osmocontractile reaction of pulvinar cells in the range of 0-100%. Tentatively, we tried to find a way that could explain this differential action. With this aim, the relationship between the inhibitory effect and important molecular physico-chemical parameters (namely lipophilicity and degree of dissociation) was drawn. In addition, the effect of a variety of these compounds was investigated on their capacity to modify the electrical transmembrane potential and induce modifications in proton fluxes. Finally, using plasma membrane vesicles purified from pulvinar tissues, we examined the effects of some selected compounds on the proton pump activity and catalytic activity of the plasma membrane H(+)-ATPase. Taken together, the results indicate that a modification of the molecular structure of phenolics may induce important variation in the activity of the compound on these early membrane events. Among the tested phenolics, salicylic acid (SA) and acetylsalicylic acid (ASA, aspirin) are of particuler note, as they showed atypical effects on the physiological processes studied. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  13. Young Children's Affective Responses to Acceptance and Rejection from Peers: A Computer-Based Task Sensitive to Variation in Temperamental Shyness and Gender

    Science.gov (United States)

    Howarth, Grace Z.; Guyer, Amanda E.; Perez-Edgar, Koraly

    2013-01-01

    This study presents a novel task examining young children's affective responses to evaluative feedback--specifically, social acceptance and rejection--from peers. We aimed to determine (1) whether young children report their affective responses to hypothetical peer evaluation predictably and consistently, and (2) whether young children's responses…

  14. Geographic variation in life-history traits: growth season affects age structure, egg size and clutch size in Andrew's toad (Bufo andrewsi).

    Science.gov (United States)

    Liao, Wen Bo; Luo, Yi; Lou, Shang Ling; Lu, Di; Jehle, Robert

    2016-01-01

    Environmental variation associated with season length is likely to promote differentiation in life-history traits, but has been little studied in natural populations of ectotherms. We investigated patterns of variation in egg size, clutch size, age at sexual maturity, maximum age, mean age, growth rate and adult body size in relation to growth season length among 17 populations of Andrew's toad (Bufo andrewsi) at different latitudes and altitudes in the Hengduan Mountains, western China. We found that egg size, age at sexual maturity, and mean age increased with decreasing length of the growth season, whereas clutch size showed a converse cline. Body size did not increase with decreasing length of the growth season, but was tightly linked to lifetime activity (i.e. the estimated number of active days during lifetime). Males and females differed in their patterns of geographic variation in growth rates, which may be the result of forces shaping the trade-off between growth and reproduction in different environments. Our findings suggest that growth season plays an important role in shaping variation in life-history traits in B. andrewsi across geographical gradients.

  15. Thyroid Function Variations Within the Reference Range Do Not Affect Quality of Life, Mood, or Cognitive Function in Community-Dwelling Older Men.

    Science.gov (United States)

    Samuels, Mary H; Kaimal, Rajani; Waring, Avantika; Fink, Howard A; Yaffe, Kristine; Hoffman, Andrew R; Orwoll, Eric; Bauer, Douglas

    2016-09-01

    Variations in thyroid function within the laboratory reference range have been associated with a number of clinical outcomes. However, quality of life, mood, and cognitive function have not been extensively studied, and it is not clear whether mild variations in thyroid function have major effects on these neurocognitive outcomes. Data were analyzed from the Osteoporotic Fractures in Men (MrOS) Study, a cohort of community-dwelling men aged 65 years and older in the United States. A total of 539 participants who were not taking thyroid medications and had age-adjusted TSH levels within the reference range underwent detailed testing of quality of life, mood, and cognitive function at baseline. The same quality of life, mood, and cognitive outcomes were measured again in 193 of the men after a mean follow-up of 6 years. Outcomes were analyzed using thyrotropin (TSH) and free thyroxine (FT4) levels as continuous independent variables, adjusting for relevant covariates. At baseline, there were no associations between TSH or FT4 levels and measures of quality of life, mood, or cognition in the 539 euthyroid men. Baseline thyroid function did not predict changes in these outcomes over a mean of 6 years in the 193 men in the longitudinal analysis. Variations in thyroid function within the age-adjusted laboratory reference range are not associated with variations in quality of life, mood, or cognitive function in community-dwelling older men.

  16. Supplementation of dextrose to the diet during the weaning to estrus interval affects subsequent variation in within-litter piglet birth weight

    NARCIS (Netherlands)

    Brand, van den H.; Soede, N.M.; Kemp, B.

    2006-01-01

    Effects of supplementation of dextrose to the diet of sows during the weaning-to-estrus interval (WEI) on subsequent litter size and within-litter variation were investigated. After weaning, 223 sows (first to fifth parity) were fed 3.5 kg/d. Half of the sows additionally received 150 g of dextrose

  17. Variation of milk urea in dairy cattle : a study on factors that affect the relationship between urea concentration in milk and urea excretion in urine

    NARCIS (Netherlands)

    Spek, J.W.

    2013-01-01

    The aim of this thesis was to increase the applicability of milk urea nitrogen concentration (MUN) as a predictor of urinary urea nitrogen excretion (UUN) by identifying and quantifying factors that can explain variation in MUN that is not related to UUN. A literature study was conducted in order to

  18. Chemical composition of modern and fossil Hippopotamid teeth and implications for paleoenvironmental reconstructions and enamel formation: 1. major and minor element variation

    Science.gov (United States)

    Brügmann, G.; Krause, J.; Brachert, T. C.; Kullmer, O.; Schrenk, F.; Ssemmanda, I.; Mertz, D. F.

    2011-05-01

    Bioapatite in mammalian teeth is readily preserved in continental sediments and represents a very important archive for reconstructions of environment and climate evolution. This project intends to provide a detailed data base of major, minor and trace element and isotope tracers for tooth apatite using a variety of microanalytical techniques. The aim is to identify specific sedimentary environments and to improve our understanding on the interaction between internal metabolic processes during tooth formation and external nutritional control and secondary alteration effects. Here, we use the electron microprobe, to determine the major and minor element contents of fossil and modern molar enamel, cement and dentin from hippopotamids. Most of the studied specimens are from different ecosystems in Eastern Africa, representing modern and fossil lakustrine (Lake Kikorongo, Lake Albert, and Lake Malawi) and modern fluvial environments of the Nile River system. Secondary alteration effects in particular FeO, MnO, SO3 and F concentrations, which are 2 to 10 times higher in fossil than in modern enamel; secondary enrichments in fossil dentin and cement are even higher. In modern and fossil enamel, along sections perpendicular to the enamel-dentin junction (EDJ) or along cervix-apex profiles, P2O5 and CaO contents and the CaO/P2O5 ratios are very constant (StdDev ~1 %). Linear regression analysis reveals very tight control of the MgO (R2∼0.6), Na2O and Cl variation (for both R2>0.84) along EDJ-outer enamel rim profiles, despite large concentration variations (40 % to 300 %) across the enamel. These minor elements show well defined distribution patterns in enamel, similar in all specimens regardless of their age and origin, as the concentration of MgO and Na2O decrease from the enamel-dentin junction (EDJ) towards the outer rim, whereas Cl displays the opposite variation. Fossil enamel from hippopotamids which lived in the saline Lake Kikorongo have a much higher MgO/Na2O

  19. Physico-chemical, functional and rheological properties of milk protein concentrate 60 as affected by disodium phosphate addition, diafiltration and homogenization.

    Science.gov (United States)

    Meena, Ganga Sahay; Singh, Ashish Kumar; Arora, Sumit; Borad, Sanket; Sharma, Rajan; Gupta, Vijay Kumar

    2017-05-01

    Ultrafiltration and diafiltration of skim milk altered delicate salt equilibrium and composition of 5× UF retentate (5× UFR), and thus adversely affected the reconstitutional and functional properties of milk protein concentrate (MPC) powders. It might be due to interaction and aggregation of proteins during spray drying. Therefore, this study was envisaged to investigate the effect of disodium phosphate (DSP) addition, diafiltration and homogenization of retentates on physico-chemical, functional and rheological properties of MPC60 powders. Solubility of fresh control powder was significantly lower than MPC60-H powder; at par with that of MPC60-DSP and MPC60-Na-K, but remained minimum after 60 days of storage at 25 ± 1 °C. The pH (6.6) adjustment of 5× UFR with DSP, significantly enhanced the dispersability, wettability, specific surface area (SSA), heat coagulation time (HCT), emulsification capacity and stability; buffer index of MPC60-DSP powder over control. Diafiltration of 5× UFR with NaCl and KCl, significantly ( P  pseudoplastic behavior, best explained by Hershel Bulkley model. These MPC60 powders with improved functional properties can be used for the improvement of quality attributes of various food formulations.

  20. SOIL CHEMICAL PROPERTIES AND GROWTH OF SUNFLOWER (HELIANTHUS ANNUUS L. AS AFFECTED BY THE APPLICATION OF ORGANIC FERTILIZERS AND INOCULATION WITH ARBUSCULAR MYCORRHIZAL FUNGI

    Directory of Open Access Journals (Sweden)

    Apolino José Nogueira da Silva

    2015-02-01

    Full Text Available The use of organic fertilizers and the inoculation of mycorrhizal fungi in the cultivation of oil crops is essential to reduce production costs and minimize negative impacts on natural resources. A field experiment was conducted in an Argissolo Amarelo (Ultisol with the aim of evaluating the effects of fertilizer application and inoculation of arbuscular mycorrhizal fungi on the growth attributes of sunflower (Helianthus annuus L. and on soil chemical properties. The experiment was conducted at the Federal University of Rio Grande do Norte, Brazil, using a randomized block design with three replicates in a 4 × 2 factorial arrangement consisting of four treatments in regard to application of organic fertilizer (liquid biofertilizer, cow urine, mineral fertilizer, and unfertilized control and two treatments in regard to arbuscular mycorrhizal fungi (with and without mycorrhizal fungi. The results showed that the physiological attributes of relative growth rate and leaf weight ratio were positively influenced by fertilization, compared to the control treatment, likely brought about by the supply of nutrients from the fertilizers applied. The growth and productivity attributes were positively affected by mycorrhization.

  1. Chemical composition and sensory quality of bovine milk as affected by type of forage and proportion of concentrate in the feed ration.

    Science.gov (United States)

    Larsen, Mette K; Kidmose, Ulla; Kristensen, Troels; Beaumont, Pierre; Mortensen, Grith

    2013-01-15

    The objective of this study was to investigate how some small changes in the forage content of maize and lucerne silage and in the ration between forage and concentrate in the diet of dairy cows affect milk quality. Milk quality was assessed by quantitative descriptive sensory analysis and by analysis of tocopherols and carotenoids as well as fatty acid composition. Changing the ratio between maize silage and lucerne silage from 5:1 to 2:1 increased milk fat content of carotenoids (23-27%) and C18:3 n3 (15%), and reduced stale aroma and creamy flavour. Increasing the proportion of concentrates in the feed ration from 0.2 to 0.4 increased energy corrected milk yield (26%), reduced fat content (-10%), increased C18 fatty acids (8-62%) and reduced C16 (-20%) content in milk fat. In addition, this milk type was described by the sensory panel as less oily, less saturated and less yellow. The changes in milk composition were related to differences in feed composition. The study revealed the potential to produce milk with a distinct composition and sensory quality based on even small changes in the feed composition that are straightforward to implement by farmers. Copyright © 2012 Society of Chemical Industry.

  2. Chemical composition of modern and fossil Hippopotamid teeth and implications for paleoenvironmental reconstructions and enamel formation - Part 1: Major and minor element variation

    Science.gov (United States)

    Brügmann, G.; Krause, J.; Brachert, T. C.; Kullmer, O.; Schrenk, F.; Ssemmanda, I.; Mertz, D. F.

    2012-01-01

    Bioapatite in mammalian teeth is readily preserved in continental sediments and represents a very important archive for reconstructions of environment and climate evolution. This project provides a comprehensive data base of major, minor and trace element and isotope tracers for tooth apatite using a variety of microanalytical techniques. The aim is to identify specific sedimentary environments and to improve our understanding on the interaction between internal metabolic processes during tooth formation and external nutritional control and secondary alteration effects. Here, we use the electron microprobe to determine the major and minor element contents of fossil and modern molar enamel, cement and dentin from Hippopotamids. Most of the studied specimens are from different ecosystems in Eastern Africa, representing modern and fossil lacustrine (Lake Kikorongo, Lake Albert, and Lake Malawi) and modern fluvial environments of the Nile River system. Secondary alteration effects - in particular FeO, MnO, SO3 and F concentrations - are 2 to 10 times higher in fossil than in modern enamel; the secondary enrichment of these components in fossil dentin and cement is even higher. In modern and fossil enamel, along sections perpendicular to the enamel-dentin junction (EDJ) or along cervix-apex profiles, P2O5 and CaO contents and the CaO/P2O5 ratios are very constant (StdDev ∼1%). Linear regression analysis reveals tight control of the MgO (R2∼0.6), Na2O and Cl variation (for both R2>0.84) along EDJ-outer enamel rim profiles, despite large concentration variations (40% to 300%) across the enamel. These minor elements show well defined distribution patterns in enamel, similar in all specimens regardless of their age and origin, as the concentration of MgO and Na2O decrease from the enamel-dentin junction (EDJ) towards the outer rim, whereas Cl displays the opposite trend. Fossil enamel from Hippopotamids which lived in the saline Lake Kikorongo have a much higher MgO/Na2

  3. Copy number variation of CCL3-like genes affects rate of progression to simian-AIDS in Rhesus Macaques (Macaca mulatta.

    Directory of Open Access Journals (Sweden)

    Jeremiah D Degenhardt

    2009-01-01

    Full Text Available Variation in genes underlying host immunity can lead to marked differences in susceptibility to HIV infection among humans. Despite heavy reliance on non-human primates as models for HIV/AIDS, little is known about which host factors are shared and which are unique to a given primate lineage. Here, we investigate whether copy number variation (CNV at CCL3-like genes (CCL3L, a key genetic host factor for HIV/AIDS susceptibility and cell-mediated immune response in humans, is also a determinant of time until onset of simian-AIDS in rhesus macaques. Using a retrospective study of 57 rhesus macaques experimentally infected with SIVmac, we find that CCL3L CNV explains approximately 18% of the variance in time to simian-AIDS (p<0.001 with lower CCL3L copy number associating with more rapid disease course. We also find that CCL3L copy number varies significantly (p<10(-6 among rhesus subpopulations, with Indian-origin macaques having, on average, half as many CCL3L gene copies as Chinese-origin macaques. Lastly, we confirm that CCL3L shows variable copy number in humans and chimpanzees and report on CCL3L CNV within and among three additional primate species. On the basis of our findings we suggest that (1 the difference in population level copy number may explain previously reported observations of longer post-infection survivorship of Chinese-origin rhesus macaques, (2 stratification by CCL3L copy number in rhesus SIV vaccine trials will increase power and reduce noise due to non-vaccine-related differences in survival, and (3 CCL3L CNV is an ancestral component of the primate immune response and, therefore, copy number variation has not been driven by HIV or SIV per se.

  4. Neisseria gonorrhoeae MutS affects pilin antigenic variation through mismatch correction and not by pilE guanine quartet binding.

    Science.gov (United States)

    Rotman, Ella; Seifert, H Steven

    2015-05-01

    Many pathogens use homologous recombination to vary surface antigens to avoid immune surveillance. Neisseria gonorrhoeae achieves this in part by changing the properties of its surface pili in a process called pilin antigenic variation (AV). Pilin AV occurs by high-frequency gene conversion reactions that transfer silent pilS sequences into the expressed pilE locus and requires the formation of an upstream guanine quartet (G4) DNA structure to initiate this process. The MutS and MutL proteins of the mismatch correction (MMC) system act to correct mismatches after replication and prevent homeologous (i.e., partially homologous) recombination, but MutS orthologs can also bind to G4 structures. A previous study showed that mutation of MutS resulted in a 3-fold increase in pilin AV, which could be due to the loss of MutS antirecombination properties or loss of G4 binding. We tested two site-directed separation-of-function MutS mutants that are both predicted to bind to G4s but are not able to perform MMC. Pilus phase variation assays and DNA sequence analysis of pilE variants produced in these mutants showed that all three mutS mutants and a mutL mutant had similar increased frequencies of pilin AV. Moreover, the mutS mutants all showed similar increased levels of pilin AV-dependent synthetic lethality. These results show that antirecombination by MMC is the reason for the effect that MutS has on pilin AV and is not due to pilE G4 binding by MutS. Neisseria gonorrhoeae continually changes its outer surface proteins to avoid recognition by the immune system. N. gonorrhoeae alters the antigenicity of the pilus by directed recombination between partially homologous pilin copies in a process that requires a guanine quartet (G4) structure. The MutS protein of the mismatch correction (MMC) system prevents recombination between partially homologous sequences and can also bind to G4s. We confirmed that loss of MMC increases the frequency of pilin antigenic variation and that

  5. Young Children’s Affective Responses to Acceptance and Rejection From Peers: A Computer-based Task Sensitive to Variation in Temperamental Shyness and Gender

    Science.gov (United States)

    Howarth, Grace Z.; Guyer, Amanda E.; Pérez-Edgar, Koraly

    2013-01-01

    This study presents a novel task examining young children’s affective responses to evaluative feedback—specifically, social acceptance and rejection—from peers. We aimed to determine (1) whether young children report their affective responses to hypothetical peer evaluation predictably and consistently, and (2) whether young children’s responses to peer evaluation vary as a function of temperamental shyness and gender. Four- to seven-year-old children (N = 48) sorted pictures of unknown, similar-aged children into those with whom they wished or did not wish to play. Computerized peer evaluation later noted whether the pictured children were interested in a future playdate with participants. Participants then rated their affective responses to each acceptance or rejection event. Children were happy when accepted by children with whom they wanted to play, and disappointed when these children rejected them. Highly shy boys showed a wider range of responses to acceptance and rejection based on initial social interest, and may be particularly sensitive to both positive and negative evaluation. Overall, the playdate task captures individual differences in affective responses to evaluative peer feedback and is potentially amenable to future applications in research with young children, including pairings with psychophysiological measures. PMID:23997429

  6. The prevalence of seasonal affective disorder in the Netherlands : A prospective and retrospective study of seasonal mood variation in the general population

    NARCIS (Netherlands)

    Mersch, PPA; Middendorp, HM; Bouhuys, AL; Beersma, DGM; van den Hoofdakker, RH; Middendorp, Hermine M.

    1999-01-01

    Background: The aim of the present study was to assess the prevalence of seasonal affective disorder (SAD) in The Netherlands. Methods: The subjects (n = 5356), randomly selected from community registers, were given the Seasonal Pattern Assessment Questionnaire and the Centre for Epidemiological

  7. Detection of QTL for metabolic and agronomic traits in wheat with adjustments for variation at genetic loci that affect plant phenology.

    Science.gov (United States)

    Hill, Camilla B; Taylor, Julian D; Edwards, James; Mather, Diane; Langridge, Peter; Bacic, Antony; Roessner, Ute

    2015-04-01

    Mapping of quantitative trait loci associated with levels of individual metabolites (mQTL) was combined with the mapping of agronomic traits to investigate the genetic basis of variation and co-variation in metabolites, agronomic traits, and plant phenology in a field-grown bread wheat population. Metabolome analysis was performed using liquid chromatography-mass spectrometry resulting in identification of mainly polar compounds, including secondary metabolites. A total of 558 metabolic features were obtained from the flag leaves of 179 doubled haploid lines, of which 197 features were putatively identified, mostly as alkaloids, flavonoids and phenylpropanoids. Coordinated genetic control was observed for several groups of metabolites, such as organic acids influenced by two loci on chromosome 7A. Five major phenology-related loci, which were introduced as cofactors in the analyses, differed in their impact upon metabolic and agronomic traits with QZad-aww-7A having more impact on the expression of both metabolite and agronomic QTL than Ppd-B1, Vrn-A1, Eps, and QZad-aww-7D. This QTL study validates the utility of combining agronomic and metabolomic traits as an approach to identify potential trait enhancement targets for breeding selection and reinforces previous results that demonstrate the importance of including plant phenology in the assessment of useful traits in this wheat mapping population. Copyright © 2015 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

  8. Do interactions between gut ecology and environmental chemicals contribute to obesity and diabetes?

    Science.gov (United States)

    Snedeker, Suzanne M; Hay, Anthony G

    2012-03-01

    Gut microbiota are important factors in obesity and diabetes, yet little is known about their role in the toxicodynamics of environmental chemicals, including those recently found to be obesogenic and diabetogenic. We integrated evidence that independently links gut ecology and environmental chemicals to obesity and diabetes, providing a framework for suggesting how these environmental factors may interact with these diseases, and identified future research needs. We examined studies with germ-free or antibiotic-treated laboratory animals, and human studies that evaluated how dietary influences and microbial changes affected obesity and diabetes. Strengths and weaknesses of studies evaluating how environmental chemical exposures may affect obesity and diabetes were summarized, and research gaps on how gut ecology may affect the disposition of environmental chemicals were identified. Mounting evidence indicates that gut microbiota composition affects obesity and diabetes, as does exposure to environmental chemicals. The toxicology and pharmacology literature also suggests that interindividual variations in gut microbiota may affect chemical metabolism via direct activation of chemicals, depletion of metabolites needed for biotransformation, alteration of host biotransformation enzyme activities, changes in enterohepatic circulation, altered bioavailability of environmental chemicals and/or antioxidants from food, and alterations in gut motility and barrier function. Variations in gut microbiota are likely to affect human toxicodynamics and increase individual exposure to obesogenic and diabetogenic chemicals. Combating the global obesity and diabetes epidemics requires a multifaceted approach that should include greater emphasis on understanding and controlling the impact of interindividual gut microbe variability on the disposition of environmental chemicals in humans.

  9. Variation of particle number size distributions and chemical compositions at the urban and downwind regional sites in the Pearl River Delta during summertime pollution episodes

    Directory of Open Access Journals (Sweden)

    D. L. Yue

    2010-10-01

    Full Text Available In order to characterize the features of particulate pollution in the Pearl River Delta (PRD in the summer, continuous measurements of particle number size distributions and chemical compositions were simultaneously performed at Guangzhou urban site (GZ and Back-garden downwind regional site (BG in July 2006. Particle number concentration from 20 nm to 10 μm at BG was (1.7±0.8×104 cm−3, about 40% lower than that at GZ, (2.9±1.1×104 cm−3. The total particle volume concentration at BG was 94±34 μm3 cm−3, similar to that at GZ, 96±43 μm3 cm−3. More 20–100 nm particles, significantly affected by the traffic emissions, were observed at GZ, while 100–660 nm particle number concentrations were similar at both sites as they are more regional. PM2.5 values were similar at GZ (69±43 μg m−3 and BG (69±58 μg m−3 with R2 of 0.71 for the daily average PM2.5 at these two sites, indicating the fine particulate pollution in the PRD region to be regional. Two kinds of pollution episodes, the accumulation pollution episode and the regional transport pollution episode, were observed. Fine particles over 100 nm dominated both number and volume concentrations of total particles during the late periods of these pollution episodes. Accumulation and secondary transformation are the main reasons for the nighttime accumulation pollution episode. SO42−, NO3 accounted for about 60% in 100–660 nm particle mass and PM2.5 increase. When south or southeast wind prevailed in the PRD region, regional transport of pollutants took place. Regional transport contributed about 30% to fine particulate pollution at BG during a regional transport case. Secondary transformation played an important role during regional transport, causing higher increase

  10. Optimization of water treatment methods for the purification of peat extraction derived runoff: Evaluation of chemical treatment response to variations in incoming water quality using a 2k factorial test design

    Science.gov (United States)

    Heiderscheidt, Elisangela; Ronkanen, Anna-Kaisa; Klöve, Björn

    2013-04-01

    The sustainable use of peatland areas requires measures to minimize and when possible eradicate the identified environmental impacts. The drainage of peatlands and other peat extraction, agriculture and forestry activities are known to increase the leaching of pollutant substances resulting in the eutrophication and siltation of receiving water bodies, causing water quality deterioration. Due to the geochemistry characteristics of peat soils the quality of peatland derived runoff water is known to oscillate with location and also with variations in runoff and peak discharge occurrences. Affordable, simple and reliable purification methods that can purify waters rich in particulates, nutrients and dissolved organic carbon while capable of coping with incoming water quality variations are therefore required. Chemical treatment is considered one of the best available technologies for the purification of peat extraction runoff water in Finland; however, until recently little research had been applied on the development of this treatment method for the purification of non-point source pollution. Chemical purification, using metal salts as coagulant agents, is currently applied in several treatment facilities in Finnish peat extraction sites. Nevertheless, variations in runoff water quality and the lack of development of field process parameters has led to the application of high chemical dosages, significant and undesirable fluctuations in purification efficiency and high metal concentration in the discharging waters. This work aims to develop and optimize the chemical purification method by using high level scientific methods to evaluate the response of the purification process to variations in water quality which are typical of peatland derived runoff. The evaluation of how the purification process responds to these variations is a critical step which will enable the development of preventive measures and optimization of relevant process parameters and thus reduce the

  11. How switches and lags in biophysical regulators affect spatial-temporal variation of soil respiration in an oak-grass savanna

    Science.gov (United States)

    Baldocchi, Dennis; Tang, Jianwu; Xu, Liukang

    2006-06-01

    Complex behavior, associated with soil respiration of an oak-grass savanna ecosystem in California, was quantified with continuous measurements of CO2 exchange at two scales (soil and canopy) and with three methods (overstory and understory eddy covariance systems, soil respiration chambers, and a below-ground CO2 flux gradient system). To partition soil respiration into its autotrophic and heterotrophic components, we exploited spatial gradients in the landscape and seasonal variations in rainfall. During the dry summer, heterotrophic respiration was dominant in the senesced grassland area, whereas autotrophic respiration by roots and the feeding of microbes by root exudates was dominant under the trees. A temporal switch in soil respiration occurred in the spring. But the stimulation of root respiration lagged the timing of leaf-out by the trees. Another temporal switch in soil respiration occurred at the start of autumn rains. This switch was induced by the rapid germination of grass seed and new grass growth. Isolated summer rain storms caused a pulse in soil respiration. Such rain events stimulated microbial respiration only; the rain was not sufficient to replenish soil moisture in the root zone or to germinate grass seed. Soil respiration lagged photosynthetic activity on hourly scales. The likely mechanism is the slow translocation of photosynthate to the roots and associated microbes. Another lag occurred on daily scales because of modulations in photosynthesis and stomatal conductance by the passage of dry and humid air masses.

  12. Seasonal variation, method of determination of bovine milk stability, and its relation with physical, chemical, and sanitary characteristics of raw milk

    OpenAIRE

    Sandro Charopen Machado; Vivian Fischer; Marcelo Tempel Stumpf; Sheila Cristina Bosco Stivanin

    2017-01-01

    ABSTRACT The objective of this research was to determine the variation of milk stability evaluated with ethanol, boiling, and coagulation time tests (CTT) to identify milk components related with stability and verify the correlation between the three methods. Bulk raw milk was collected monthly at 50 dairy farms from January 2007 to October 2009 and physicochemical attributes, somatic cell (SCC), and total bacterial counts (TBC) were determined. Milk samples were classified into low, medium, ...

  13. Factors affecting variation in the vase life response of waxflower cultivars (Myrtaceae: Chamelaucium Desf. and Verticordia spp. Desf. tested under various vase solutions

    Directory of Open Access Journals (Sweden)

    Dung Cao D.

    2016-06-01

    Full Text Available The effects of genotype and vase solutions on the vase lives of waxflower cultivars were studied. The vase life of 16 cultivars derived from different genetic backgrounds showed a variation. The vase life of Chamelaucium uncinatum cultivars held in deionised water was generally the shortest, with four cultivars averaging 9.5 and 8.9 days for flowers and leaves while the vase lives of C. uncinatum × megalopetalum hybrids were on average 16.0 and 25.0 days for flowers and leaves, respectively. The hybrid ‘Southern Stars’ with C. uncinatum × Verticordia plumosa as parents had the longest flower vase life of 24.9 days, although another Verticordia × Chamelaucium had a 9.5-day flower vase life and other hybrids of the cultivars of C. uncinatum and Verticordia grandis Desf. (‘WX73’, C. sp. Gingin Marchantii (‘WX97’ and C. floriferum (‘Lady Stephanie’ as a parent had intermediate to short vase lives of 11.4 to 15.5 days. The cultivars responded most to 8-hydroxyquniline sulphate (HQS + sucrose or HQS + sucrose + silver thiosulphate (STS, being 1.5- to 1.6-folds higher than in deionized water. The cultivars showed a varied response to a vase solution of sucrose + HQS + STS, with which C. uncinatum vase life increased 1.9-fold compared to 1.7-fold for C. megalopetalum. Waxflowers were found to be susceptible to water stress, causing flowers to close and shortening vase life. On average for the 80 cultivar-vase solution combinations tested, flower vase life ended when the stems reached 75.5 ± 5% fresh weigh. Longer vase life cultivars had a greater ability of maintaining a water balance at or above 75% for longer.

  14. Intercontinental chemical variation in the invasive ant Wasmannia auropunctata (Roger) (Hymenoptera Formicidae): a key to the invasive success of a tramp species

    Science.gov (United States)

    Errard, Christine; Delabie, Jacques; Jourdan, Hervé; Hefetz, Abraham

    2005-07-01

    Unicoloniality emerges as a feature that characterizes successful invasive species. Its underlying mechanism is reduced intraspecific aggression while keeping interspecific competitiveness. To that effect, we present here a comparative behavioural and chemical study of the invasive ant Wasmannia auropunctata in parts of its native and introduced ranges. We tested the hypothesis that introduced populations (New Caledonia archipelago) have reduced intraspecific aggression relative to native populations (e.g., Ilhéus area, Brazil) and that this correlates with reduced variability in cuticular hydrocarbons (CHCs). As predicted, there was high intraspecific aggression in the Brazilian populations, but no intraspecific aggression among the New Caledonian populations. However, New Caledonian worker W. auropunctata remained highly aggressive towards ants of other invasive species. The chemical data corresponded with the behaviour. While CHCs of ants from the regions of Brazil diverged, the profiles of ants from various localities in New Caledonia showed high uniformity. We suggest that in New Caledonia W. auropunctata appears to behave as a single supercolony, whereas in its native range it acts as a multicolonial species. The uniformity of recognition cues in the New Caledonia ants may reflect a process whereby recognition alleles became fixed in the population, but may also be the consequence of a single introduction event and subsequent aggressive invasion of the ecosystem. Chemical uniformity coupled with low intraspecific but high interspecific aggression, lend credence to the latter hypothesis.

  15. Variation in Chst8 gene expression level affects PrPC to PrPSc conversion efficiency in prion-infected Mov cells.

    Science.gov (United States)

    Martin, Renaud; Chantepie, Sandrine; Chapuis, Jérôme; Le-Duc, Aurélien; Maftah, Abderrahman; Papy-Garcia, Dulcé; Laude, Hubert; Petit, Jean-Michel; Gallet, Paul-François

    2011-10-28

    The conversion of the endogenous cellular prion protein to an abnormally folded isoform is a hallmark of transmissible spongiform encephalopathies. It occurs when a misfolded prion protein contacts the cellular PrP. Among the molecular partners suggested to be involved in the misfolding process, the glycosaminoglycans seem to be good candidates. The present study was aimed to examine a possible link between PrP conversion efficiency and transcript level of Chst8 gene that encodes the carbohydrate N-acetylgalactosamine 4-O-sulfotransferase 8. Mov cells expressing ovine PrP were transfected with shRNA directed against Chst8 transcripts. Resulting clones were characterized for their Chst8 and Prnp transcript levels, and for their content in sulfated glycosaminoglycans, more particularly sulfated chondroitins. Unexpectedly, the decreased amount of Chst8 transcript induced an increase of the chondroitin sulfate percentage among total GAGs, with an increased amount of 4-O-sulfation of GalNAc residues. Upon to infection by a sheep prion, a slight amount of PrP(Sc) was observed, which rapidly disappeared upon subpassaging. Together, these findings indicate that the Chst8 transcript level affects the glycosaminoglycan environment of the cellular prion protein, and as a consequence its ability for conversion into PrP(Sc). Copyright © 2011 Elsevier Inc. All rights reserved.

  16. Recent sequence variation in probe binding site affected detection of respiratory syncytial virus group B by real-time RT-PCR.

    Science.gov (United States)

    Kamau, Everlyn; Agoti, Charles N; Lewa, Clement S; Oketch, John; Owor, Betty E; Otieno, Grieven P; Bett, Anne; Cane, Patricia A; Nokes, D James

    2017-03-01

    Direct immuno-fluorescence test (IFAT) and multiplex real-time RT-PCR have been central to RSV diagnosis in Kilifi, Kenya. Recently, these two methods showed discrepancies with an increasing number of PCR undetectable RSV-B viruses. Establish if mismatches in the primer and probe binding sites could have reduced real-time RT-PCR sensitivity. Nucleoprotein (N) and glycoprotein (G) genes were sequenced for real-time RT-PCR positive and negative samples. Primer and probe binding regions in N gene were checked for mismatches and phylogenetic analyses done to determine molecular epidemiology of these viruses. New primers and probe were designed and tested on the previously real-time RT-PCR negative samples. N gene sequences revealed 3 different mismatches in the probe target site of PCR negative, IFAT positive viruses. The primers target sites had no mismatches. Phylogenetic analysis of N and G genes showed that real-time RT-PCR positive and negative samples fell into distinct clades. Newly designed primers-probe pair improved detection and recovered previous PCR undetectable viruses. An emerging RSV-B variant is undetectable by a quite widely used real-time RT-PCR assay due to polymorphisms that influence probe hybridization affecting PCR accuracy. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  17. Identification of naturally occurring amino acid variations that affect the ability of the measles virus C protein to regulate genome replication and transcription.

    Science.gov (United States)

    Bankamp, Bettina; Wilson, Jenna; Bellini, William J; Rota, Paul A

    2005-05-25

    The C protein of measles virus (MV C) is a basic protein of 186 amino acids (aa) that plays at least two roles in infected cells, interference with the innate immune response and modulation of viral polymerase activity. In this study, Northern blots were used to demonstrate that C proteins from three vaccine strains and three wild-type isolates of MV downregulated both mRNA transcription and genome replication in a plasmid-based mini-genome assay. The effect on transcription always paralleled the effect on replication; however, the six MV C proteins varied considerably in their ability to inhibit polymerase activity. Though the amino-terminal 45 aa of the C protein are more variable among different MV strains than the remaining 75% of the protein, the ability of the MV C proteins to inhibit polymerase activity was not regulated by substitutions in the amino terminus, but rather by the more conserved region containing aa 46-167. Naturally occurring substitutions at positions 147 and 166, but not 88 and 186, were found to regulate MV C protein activity. Deletion of the carboxyl-terminal 19 aa did not affect the polymerase-modulating activity. Though we did not find a link between the aa changes in MV C and attenuation, these data provide new information regarding the functions of this non-structural protein.

  18. Variations in the chemical composition of the submicron aerosol and in the sources of the organic fraction at a regional background site of the Po Valley (Italy)

    Science.gov (United States)

    Bressi, Michael; Cavalli, Fabrizia; Belis, Claudio A.; Putaud, Jean-Philippe; Fröhlich, Roman; Martins dos Santos, Sebastiao; Petralia, Ettore; Prévôt, André S. H.; Berico, Massimo; Malaguti, Antonella; Canonaco, Francesco

    2016-10-01

    Fine particulate matter (PM) levels and resulting impacts on human health are in the Po Valley (Italy) among the highest in Europe. To build effective PM abatement strategies, it is necessary to characterize fine PM chemical composition, sources and atmospheric processes on long timescales (> months), with short time resolution (organic fraction. Although previous studies have been conducted in this region, none of them addressed all these aspects together. For the first time in the Po Valley, we investigate the chemical composition of nonrefractory submicron PM (NR-PM1) with a time resolution of 30 min at the regional background site of Ispra during 1 full year, using the Aerodyne Aerosol Chemical Speciation Monitor (ACSM) under the most up-to-date and stringent quality assurance protocol. The identification of the main components of the organic fraction is made using the Multilinear-Engine 2 algorithm implemented within the latest version of the SoFi toolkit. In addition, with the aim of a potential implementation of ACSM measurements in European air quality networks as a replacement of traditional filter-based techniques, parallel multiple offline analyses were carried out to assess the performance of the ACSM in the determination of PM chemical species regulated by air quality directives. The annual NR-PM1 level monitored at the study site (14.2 µg m-3) is among the highest in Europe and is even comparable to levels reported in urban areas like New York City and Tokyo. On the annual basis, submicron particles are primarily composed of organic aerosol (OA, 58 % of NR-PM1). This fraction was apportioned into oxygenated OA (OOA, 66 %), hydrocarbon-like OA (HOA, 11 % of OA) and biomass burning OA (BBOA, 23 %). Among the primary sources of OA, biomass burning (23 %) is thus bigger than fossil fuel combustion (11 %). Significant contributions of aged secondary organic aerosol (OOA) are observed throughout the year. The unexpectedly high degree of oxygenation

  19. Comprehensive Quality Assessment Based Specific Chemical Profiles for Geographic and Tissue Variation in Gentiana rigescens Using HPLC and FTIR Method Combined with Principal Component Analysis

    Directory of Open Access Journals (Sweden)

    Jie Li

    2017-12-01

    Full Text Available Roots, stems, leaves, and flowers of Longdan (Gentiana rigescens Franch. ex Hemsl were collected from six geographic origins of Yunnan Province (n = 240 to implement the quality assessment based on contents of gentiopicroside, loganic acid, sweroside and swertiamarin and chemical profile using HPLC-DAD and FTIR method combined with principal component analysis (PCA. The content of gentiopicroside (major iridoid glycoside was the highest in G. rigescens, regardless of tissue and geographic origin. The level of swertiamarin was the lowest, even unable to be detected in samples from Kunming and Qujing. Significant correlations (p < 0.05 between gentiopicroside, loganic acid, sweroside, and swertiamarin were found at inter- or intra-tissues, which were highly depended on geographic origins, indicating the influence of environmental conditions on the conversion and transport of secondary metabolites in G. rigescens. Furthermore, samples were reasonably classified as three clusters along large producing areas where have similar climate conditions, characterized by carbohydrates, phenols, benzoates, terpenoids, aliphatic alcohols, aromatic hydrocarbons, and so forth. The present work provided global information on the chemical profile and contents of major iridoid glycosides in G. rigescens originated from six different origins, which is helpful for controlling quality of herbal medicines systematically.

  20. Variation of the chemical contents and morphology of gunshot residue in the surroundings of the shooting pistol as a potential contribution to a shooting incidence reconstruction.

    Science.gov (United States)

    Brożek-Mucha, Zuzanna

    2011-07-15

    A study of the chemical contents and sizes of gunshot residue originating from 9×18mm PM ammunition, depositing in the vicinity of the shooting person was performed by means of scanning electron microscopy and energy dispersive X-ray spectrometry. Samples of the residue were collected from targets placed at various distances in the range 0-100cm as well as from hands and clothing of the shooting person. Targets were covered by fragments of white cotton fabric or black bovine leather. In the case of cotton targets microtraces were collected from circles of 5 and 10cm in radius. Results of the examinations in the form of numbers of particles, proportions of their chemical classes and dimensions revealed a dependence on the distance from the gun muzzle, both in the direction of shooting and in the opposite one, i.e., on the shooting person. The parameters describing gunshot residue differed also depending on the kind of the target substrate. The kind of obtained information gives rise to understanding the general rules of the dispersion of gunshot residue in the surroundings of the shooting gun. Thus, it may be utilised in the reconstruction of shooting incidences, especially in establishing the mutual positions of the shooter and other participants of the incident. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  1. Inter-comparison of Seasonal Variation, Chemical Characteristics, and Source Identification of Atmospheric Fine Particles on Both Sides of the Taiwan Strait

    Science.gov (United States)

    Li, Tsung-Chang; Yuan, Chung-Shin; Huang, Hu-Ching; Lee, Chon-Lin; Wu, Shui-Ping; Tong, Chuan

    2016-01-01

    The spatiotemporal distribution and chemical composition of atmospheric fine particles in areas around the Taiwan Strait were firstly investigated. Fine particles (PM2.5) were simultaneously collected at two sites on the west-side, one site at an offshore island, and three sites on the east-side of the Taiwan Strait in 2013–2014. Field sampling results indicated that the average PM2.5 concentrations at the west-side sampling sites were generally higher than those at the east-side sampling sites. In terms of chemical composition, the most abundant water-soluble ionic species of PM2.5 were SO42−, NO3−, and NH4+, while natural crustal elements dominated the metallic content of PM2.5, and the most abundant anthropogenic metals of PM2.5 were Pb, Ni and Zn. Moreover, high OC/EC ratios of PM2.5 were commonly observed at the west-side sampling sites, which are located at the downwind of major stationary sources. Results from CMB receptor modeling showed that the major sources of PM2.5 were anthropogenic sources and secondary aerosols at the both sides, and natural sources dominated PM2.5 at the offshore site. A consistent decrease of secondary sulfate and nitrate contribution to PM2.5 suggested the transportation of aged particles from the west-side to the east-side of the Taiwan Strait. PMID:26973085

  2. Downward Heat Penetration below Seasonal Thermocline and its Impact on Sea Surface Temperature Variation Affected by Net Heat Flux during Summer Season

    Science.gov (United States)

    Hosoda, S.; Nonaka, M.; Tomita, T.; Taguchi, B.; Tomita, H.; Iwasaka, N.

    2016-02-01

    Oceanic heat capacity of the upper layer is a key of the change in the sea surface temperature (SST) affecting air-sea heat exchange and of the temporal scale of SST variability. In the past, studies of SST variability associated with the air-sea heat exchange have mainly focused on the conditions during the winter, because wintertime deep mixed layer (ML) accumulates a huge amount of heat to the atmosphere. On the contrary, ML during the warming season is thinner than it is during the cooling season, being only a few tens of meters deep at mid- and high- latitudes, bounded by a shallow and sharp seasonal thermocline. Since the ML that directly communicates with the atmosphere is thin, the ocean has been considered to play a passive role in air-sea interactions during the warming season. In this study, we clarified that subsurface ocean plays an important role to seasonal changes of SST and heat capacity during the warming season using observational data of Argo and J-OFURO2, which is net heat flux (Qnet) data from satellites. To clarify the role of upper ocean to the Qnet during summer, we introduce a concept of heat penetration depth (HPD), defined as the depth to which Qnet distinctly penetrates below the seasonal thermocline. Then we assume vertical one dimensional process between Qnet and temporal heat content (HC) change integrating temperature from surface to HPD. The vertical one dimensional process can be assumed in almost mid- and high-latitude NP, and we successfully characterize the heat capacity in terms of the HC above the HPD. The downward heat penetration below the shallow seasonal thermocline is widely found throughout the NP. On the basis of a simple estimation that the amount of heat accumulated by summer Qnet in the NP, about two-thirds of Qnet penetrates below the shallow seasonal thermocline. The effect of heat penetration also makes a magnitude of seasonal change in SST to be smaller, at least a half of that the magnitude under the assumption

  3. Interdisciplinary Workshop on the Physical-Chemical-Biological Processes Affecting Archeological Sites Held in College Station, Texas on May 27-29, 1987

    Science.gov (United States)

    1989-01-01

    chemicals, and labor , it is not economically feasible to treat every artifact from a site. The decision as to what to treat or not to treat must be...pp. 135-138. CULTURAL Archaeology, field methodology COREMANS, P., 1968b, Clima ! qnd microciimate. In Conservation of Cultural Property with Special

  4. The efficacy of chemical sanitizers on the reduction of Salmonella Typhimurium and Escherichia coli affected by bacterial cell history and water quality

    NARCIS (Netherlands)

    Banach, J.L.; Bokhorst-van de Veen, van H.; Overbeek, van L.S.; Zouwen, van der P.S.; Fels, van der Ine; Nierop Groot, M.N.

    2017-01-01

    Washing fresh produce with potable water helps to remove microorganisms, providing about a 1- to 2-log reduction, but this process can also pose an opportunity for cross-contamination of bacteria in the washing tank. The objective of this study was to evaluate the efficacy of three chemical

  5. Evaluation of yield and some physiological traits of forage corn affected by chemical and biological nitrogen fertilizers intercropped with sweet basil

    Directory of Open Access Journals (Sweden)

    Sajad KORDI

    2017-06-01

    Full Text Available In order to evaluate yield and some physiological traits of forage corn under nitrogen fertilizers (biological, chemical and integrated in additive intercropping with basil a field experiment was carried out in the Experimental Farm of Faculty of Agriculture, Lorestan University during 2014-2015 growing seasons. Treatments were arranged in a factorial experiment based on randomized complete blocks design with three replications. Experimental treatments were 100% chemical fertilizer (N, bio-fertilizer (nitroxin, integration of bio-fertilizer + 50% chemical fertilizer and control in different intercropping systems consisted of sole cropping corn and the additive intercropping of corn + 25% sweet basil, corn + 50% sweet basil, corn + 75% sweet basil and corn + 100% sweet basil. The results showed that integration of bio-fertilizer + 50% chemical fertilizer had the highest number of green leaves per plant (11.72 and leaf area index (LAI (3.75 and there was no significant difference between this treatment and using 100% chemical fertilizer (N in plant height, stem dry weight, chlorophyll a, chlorophyll b and carotenoids contents. Among different intercropping systems the highest plant height (179.25 cm, number of green leaves per plant (11.4, leaf dry weight (5.64 ton*ha-1, ear dry weight (7.19 ton*ha-1, stem dry weight (6.11 ton*ha-1, total dry weight (19.22 ton*ha-1, chlorophyll a (0.62 mg*g-1 FW, chlorophyll b (0.42 mg*g-1 FW, and total chlorophyll (1.04 mg*g-1 FW were obtained from sole cropping pattern. However, sole cropping pattern in terms of mentioned traits except for number of green leaves per plant, ear dry weight and total dry weight had no significant difference with corn + 25% sweet basil and corn + 50% sweet basil treatments The results showed that integration of bio-fertilizer + 50% chemical fertilizer could be considered as an approach to reduce the consumption of chemical fertilizers for sustainable agriculture

  6. Variations in the chemical composition of the submicron aerosol and in the sources of the organic fraction at a regional background site of the Po Valley (Italy

    Directory of Open Access Journals (Sweden)

    M. Bressi

    2016-10-01

    Full Text Available Fine particulate matter (PM levels and resulting impacts on human health are in the Po Valley (Italy among the highest in Europe. To build effective PM abatement strategies, it is necessary to characterize fine PM chemical composition, sources and atmospheric processes on long timescales (> months, with short time resolution (< day, and with particular emphasis on the predominant organic fraction. Although previous studies have been conducted in this region, none of them addressed all these aspects together. For the first time in the Po Valley, we investigate the chemical composition of nonrefractory submicron PM (NR-PM1 with a time resolution of 30 min at the regional background site of Ispra during 1 full year, using the Aerodyne Aerosol Chemical Speciation Monitor (ACSM under the most up-to-date and stringent quality assurance protocol. The identification of the main components of the organic fraction is made using the Multilinear-Engine 2 algorithm implemented within the latest version of the SoFi toolkit. In addition, with the aim of a potential implementation of ACSM measurements in European air quality networks as a replacement of traditional filter-based techniques, parallel multiple offline analyses were carried out to assess the performance of the ACSM in the determination of PM chemical species regulated by air quality directives. The annual NR-PM1 level monitored at the study site (14.2 µg m−3 is among the highest in Europe and is even comparable to levels reported in urban areas like New York City and Tokyo. On the annual basis, submicron particles are primarily composed of organic aerosol (OA, 58 % of NR-PM1. This fraction was apportioned into oxygenated OA (OOA, 66 %, hydrocarbon-like OA (HOA, 11 % of OA and biomass burning OA (BBOA, 23 %. Among the primary sources of OA, biomass burning (23 % is thus bigger than fossil fuel combustion (11 %. Significant contributions of aged secondary organic aerosol (OOA

  7. [Chemical composition and daily variation of melt water during ablation season in monsoonal temperate Glacier region: a case study of Baishui Glacier No. 1].

    Science.gov (United States)

    Zhu, Guo-Feng; Pu, Tao; He, Yuan-Qing; Wang, Pei-Zhen; Kong, Jian-Long; Zhang, Ning-Ning; Xin, Hui-Juan

    2012-12-01

    Melt water samples collected continuously from 29 August to 3 September 2009 in the Baishui Glacier No. 1 at elevation of 4750 m were analyzed for pH, conductivity, delta18O and inorganic ions. The results showed that the pH had obvious diurnal variations and was increased slightly by the influence of precipitation. The dissolution of alkaline soluble salts in the dust was the main reason for the increase of melt water conductivity; the value of delta18O was relatively low in strong ablation period and high in slight ablation period. Different from other research areas, the concentrations of Na+, K+, which were influenced by lithological and marine water vapor, were higher than that of Mg2+ in the study area; HCO3- and Ca2+ accounted for more than 80% of total ions in snow and ice melt water, indicating that the ions mainly came from limestone and the melt water was a typical carbonate solution; The content of melt water had an obvious daily change with temperature change, but the response amplitudes were different; Monsoon transport, local rock lithology, human industrial and agricultural activities were the main sources of inorganic ions and the deciding factors of the ion composition in the Baishui Glacier No. 1.

  8. DETERMINING THE ROLE OF INDIVIDUAL FLY ASH PARTICLES IN INFLUENCING THE VARIATION IN THE OVERALL PHYSICAL, MORPHOLOGICAL, AND CHEMICAL PROPERTIES OF FLY ASH

    Directory of Open Access Journals (Sweden)

    Usman Haider

    2016-08-01

    Full Text Available The properties of fly ashes vary because of the differences in the properties of their individual particles, and the determination of variation in these properties is of interest to the industries which use pulverized raw fly ash in applications, such as in cementitious materials and in the recovery of certain rare elements from raw fly ash. To investigate the differences in individual particles, four pulverized raw fly ashes from thermal power plants of the Czech Republic were used in this research. It was observed from FE-SEM that all four fly ashes consist of glassy hollow spherical, solid spherical, porous spherical, bright spherical, porous slaggy and compact slaggy particles. Box and whisker diagrams were plotted from the data of EDX individual particle analyses, which showed that the data of percentages for the Si, Al, and Fe elements is more scattered as compared to other elements. It was further observed from ternary phase diagrams and pseudo coloured images, that nature of fly ash particles changes from alumino silicate glassy to alumino silicate calcite metallic to pure ferro-metallic,where glassy particles showed high percentages and pure calcite particles were absent in fly ashes. Furthermore, a comparison between the XRF, the EDX total area analyses, showed that the EDX individual particle analysis gives more realistic and reliable data with median, mean, and the standard deviation for percentages of each element present in the fly ashes.

  9. Spatial distribution and temporal variation of chemical properties of drainage watercourses in rural and peri-urban areas of Novi Sad (Serbia)-a case study.

    Science.gov (United States)

    Savic, Radovan; Ondrasek, Gabrijel; Blagojevic, Bosko; Bubalo Kovacic, Marina; Zemunac, Rados

    2017-12-29

    Waters are among to the most vulnerable environmental resources exposed to the impact of various point and non-point pollutants from rural/urban activities. Systematic and long-term monitoring of hydro-resources is therefore of crucial importance for sustainable water management, although such practice is lacking across many (agro-)hydro-ecosystems. In the presented study, for the first time, the spatial distribution (covering almost 9000 ha) and temporal variation (2006-2013) in certain quality parameters was characterized in drainage watercourses Tatarnica and Subic, whose catchment is rural and suburban areas close to the city of Novi Sad, Republic of Serbia. Based on majority of observed parameters, both watercourses belonged to I and II water quality classes, with occasional presence of certain parameters (e.g., suspended solids, total phosphorus; ammonium) at extreme values exacerbating both watercourses to classes IV and V. The value of the synthetic pollution index (i.e., a combined effect of all considered parameters) showed a higher degree of water pollution in watercourse Subic (on average 2.00) than Tatarnica (on average 0.72). Also, cluster analysis for watercourse Tatarnica detected two groups of parameters (mostly related to nutrients and organic matter), indicating more complex impacts on water quality during the observed period, in which elucidation thus established water quality monitoring program would be of great importance.

  10. Variations in the chemical composition and standardized ileal digestibility of amino acids in eight genotypes of triticale fed to growing pigs.

    Science.gov (United States)

    Strang, E J P; Eklund, M; Rosenfelder, P; Htoo, J K; Mosenthin, R

    2017-04-01

    The study was conducted to determine the chemical composition, physical characteristics, and standardized ileal digestibility (SID) of CP and AA of 8 currently available genotypes of triticale fed to growing pigs. The genotypes included Grenado, Cando, Agostino, Massimo, Tarzan, HYT Prime, SW Talentro, and Cultivo. Eight barrows with an initial BW of 31 ± 2 kg were fitted with simple T-cannulas at the distal ileum and allotted to an 8 × 8 Latin square design with 8 periods of 7 d each and 8 assay diets. The N-free method was used to determine basal ileal endogenous CP and AA losses. The 8 assay diets contained 1 of 8 triticale genotypes as the sole source of CP and AA. The triticale genotypes were grown under identical environmental conditions on the same site. Among the 8 genotypes, contents of CP ranged from 104.7 to 118.1 g/kg (as-fed basis). The content of total nonstarch polysaccharides and NDF ranged, on an as-fed basis, from 84.6 to 99.5 g/kg and from 88.4 to 149.0 g/kg, respectively. Among the 8 genotypes, SID of CP ranged from 81% in Grenado to 85% in Massimo and Tarzan. The SID of CP and AA did not differ among triticale genotypes except for SID of Arg, Glu, and Gly ( tables. Among the 8 triticale genotypes, standardized ileal digestible content (cSID) of CP followed total CP content and ranged from 84.8 to 98.7 g/kg (as-fed basis), with the lowest ( chemical composition, physical characteristics, and SID of CP and AA of 8 triticale genotypes grown under similar conditions. However, as most of the present SID values are less than those in feed tables, future research is warranted to elaborate whether these differences are caused by experimental conditions or reflect a consistent decrease that needs to be accounted for in feed tables.

  11. Chemical composition and bioactive compounds of garlic (Allium sativum L.) as affected by pre- and post-harvest conditions: A review.

    Science.gov (United States)

    Martins, Natália; Petropoulos, Spyridon; Ferreira, Isabel C F R

    2016-11-15

    Garlic (Allium sativum L.) is considered one of the twenty most important vegetables, with various uses throughout the world, either as a raw vegetable for culinary purposes, or as an ingredient of traditional and modern medicine. Furthermore, it has also been proposed as one of the richest sources of total phenolic compounds, among the usually consumed vegetables, and has been highly ranked regarding its contribution of phenolic compounds to human diet. This review aims to examine all the aspects related with garlic chemical composition and quality, focusing on its bioactive properties. A particular emphasis is given on the organosulfur compounds content, since they highly contribute to the effective bioactive properties of garlic, including its derived products. The important effects of pre-harvest (genotype and various cultivation practices) and post-harvest conditions (storage conditions and processing treatments) on chemical composition and, consequently, bioactive potency of garlic are also discussed. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Chemical composition of the essential oil of Moluccella spinosa L. (Lamiaceae) collected wild in Sicily and its activity on microorganisms affecting historical textiles.

    Science.gov (United States)

    Casiglia, Simona; Jemia, Mariem Ben; Riccobono, Luana; Bruno, Maurizio; Scandolera, Elia; Senatore, Felice

    2015-01-01

    In this study the chemical composition of the essential oil from aerial parts of Moluccella spinosa L. collected in Sicily was evaluated by GC and GC-MS. The main components of M. spinosa L. were α-pinene (26.6%), caryophyllene oxide (16.8%) and β-caryophyllene (8.6%). A comparison with other studied oils of genus Moluccella is made. Antibacterial and antifungal activities against some microorganisms infesting historical textiles were also determined.

  13. Chemical composition and sensory properties of non-wooded and wooded Shiraz (Vitis vinifera L.) wine as affected by vineyard row orientation and grape ripeness level.

    Science.gov (United States)

    Hunter, Jacobus J; Volschenk, Cornelis G

    2017-10-27

    The study aimed to unravel vineyard row orientation (NS, EW, NE-SW, NW-SE) and grape ripeness level (23, 25, 27 °Balling) implications for grape and wine composition and sensory properties/style (non-wooded/wooded wines) of Vitis vinifera L. cv. Shiraz (rootstock 101-14 Mgt). Soluble solid/titratable acidity ratios were lowest for EW, whereas warmer canopy sides (NW, N, NE) advanced grape ripening. Skin anthocyanins and phenolics generally decreased with ripening. NW-SE rows and S, SE, E and NE canopy sides showed highest skin total anthocyanins and phenolics. Wine total anthocyanins and phenolics increased with grape ripening; EW had lower values. Wine phenolic contents differed between canopy sides; N, NE, E and SE tended higher. Wine sensory profiles increased with grape ripening. For non-wooded wines, NW-SE and NE-SW row orientations generally resulted in highest scores, followed by NS. For EW rows, the N side presented better wines. Wood addition enhanced specific sensory descriptor perceptions. A large collection of wine styles surfaced in the same vineyard and terroir, increasing options to contribute positively to sustainable products. The study generated globally applicable, novel information vital for unlocking and valorising terroir/site potential for grape and wine chemical composition and wine sensory/style properties. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  14. Influence of Polish Climate Conditions on Content and the Chemical Variation of Volatiles in the Roots of Six Eleutherococcus Species and Their Potential Use

    Directory of Open Access Journals (Sweden)

    Daniel Załuski

    2016-03-01

    Full Text Available The aim of this study was the term of the climate influence on essential oil and aroma components of six Eleutherococcus species [E. senticosus (Rupr. & Maxim. Maxim., E. setchuensis (Harms Nakai, E. sessiliflorus (Rupr. & Maxim. S. Y. Hu, E. gracilistylus (W. W. Smith S. Y. Hu, E. henryi Oliv., E. divaricatus (Siebold & Zucc. S. Y. Hu ] cultivated in Poland. The hydrodistilled volatiles of the samples were ranged from 0.2% to 0.4%. The components of the determined volatiles were analyzed by GC/MS/MS. Thirty of the same compounds were present in all samples. Major components of the samples were (E,E-farnesol (43.6-6.9%, (E,Z-farnesol (7.2-0.7%, (Z,E-farnesol (1.4-0.1%, tetradecanoic acid (9.91-2.08%, and pentadecanoic acid (12.8-3.5%. Highest (E,E-farnesol content (43.6% was determined in the roots of E. divaricatus. This compound may be considered as chemical marker of the species. This is the first time, when the analysis of volatiles in the roots of Eleutherococcus spp. cultivated in Poland was performed. This study provides a platform for further investigation for the isolation and pharmacological activity of active principles.

  15. Variations in fatty acid composition, glucosinolate profile and some phyto chemical contents in selected oil seed rape (Brassica napus L.) cultivars

    Energy Technology Data Exchange (ETDEWEB)

    El-Din Saad El-Beltag, H.; Mohamed, A. A.

    2010-07-01

    Rapeseed (Brassica napus L.) is now the third most important source of edible oil in the world after soybean and palm oil. In this study seeds of five different rapeseed cultivars namely; pactol, silvo, topas, serw 4 and serw 6 were evaluated for their fatty acid composition, glucosinolate profile, amino acids, total tocopherols and phenolic content. Among all cultivars significant variability in fatty acids were observed. The oleic acid (C18:1) ranged from 56.31% to 58.67%, linoleic acid (C18:2) from 10.52% to 13.74%, {alpha}-linolenic acid (C18:3) from 8.83% to 10.32% and erucic acid (22:1) from 0.15% to 0.91%. The glucosinolate profile of rapeseed was also separated and identified using high-performance liquid chromatography. Small variations in the glucosinolate profile were observed among all tested cultivars; however, progoitrin and gluconapin were the major glucosinolate found. Additionally, silvo cultivar showed the highest total glucosinolate contents (5.97 {mu}mol/g dw). Generally, the contents of aspartic, glutamic, arginine and leucine were high, while the contents of tyrosine and isoleucine were low among all cultivars. For total tocopherols, the results indicated that both serw 6 and pactol cultivars had the highest total tocopherol contents (138.3 and 102.8 mg/100 g oil, respectively). Total phenolic contents varied from 28.0 to 35.4 mg/g dw. The highest total phenolic content was found in topas while the lowest value was detected in serw 6. These parameters; fatty acid contents, glucosinolate profile and amino acids together with total tocopherols and phenolic contents, could be taken into consideration by oilseed rape breeders as selection criteria for developing genotypes with modified seed quality traits in Brassica napus L. (Author)

  16. Seasonal variation, method of determination of bovine milk stability, and its relation with physical, chemical, and sanitary characteristics of raw milk

    Directory of Open Access Journals (Sweden)

    Sandro Charopen Machado

    Full Text Available ABSTRACT The objective of this research was to determine the variation of milk stability evaluated with ethanol, boiling, and coagulation time tests (CTT to identify milk components related with stability and verify the correlation between the three methods. Bulk raw milk was collected monthly at 50 dairy farms from January 2007 to October 2009 and physicochemical attributes, somatic cell (SCC, and total bacterial counts (TBC were determined. Milk samples were classified into low, medium, and high stability to ethanol test when coagulation occurred at 72 °GL, between 74 and 78 °GL, and above 78 °GL, respectively. Univariate analysis was performed considering the effects of year, months, and interaction in a completely randomized design. Principal factor analysis and logistic regression were done. There was an interaction between months and years for stability to the ethanol test and coagulation time. All samples were stable at the boiling test. Boiling test was not related to ethanol and coagulation time tests. Coagulation time was weakly but positively correlated with ethanol test. Broken line analysis revealed that milk stability measured with CTT and ethanol tests decreased sharply when SCC attained 790,000 or 106 cell/mL of milk, respectively. Milk stability measured with ethanol test decreased when TBC was higher than 250,000 cfu/mL, while there was no inflexion point between TBC and stability measured with CTT. Milk with high stability presented lower values for acidity, TBC, and SCC but higher values for pH, lactose, protein, and CTT compared with low-stability milk. Due to the execution easiness, single-point cut-off result and low cost, we do not recommend the replacement of ethanol test for boiling or coagulation time test.

  17. Chemical and boron-isotope variations in tourmalines from an S-type granite and its source rocks: the Erongo granite and tourmalinites in the Damara Belt, Namibia

    Science.gov (United States)

    Trumbull, R. B.; Krienitz, M.-S.; Gottesmann, B.; Wiedenbeck, M.

    2008-01-01

    Tourmaline is widespread in metapelites and pegmatites from the Neoproterozoic Damara Belt, which form the basement and potential source rocks of the Cretaceous Erongo granite. This study traces the B-isotope variations in tourmalines from the basement, from the Erongo granite and from its hydrothermal stage. Tourmalines from the basement are alkali-deficient schorl-dravites, with B-isotope ratios typical for continental crust (δ11B average -8.4‰ ± 1.4, n = 11; one sample at -13‰, n = 2). Virtually all tourmaline in the Erongo granite occurs in distinctive tourmaline-quartz orbicules. This “main-stage” tourmaline is alkali-deficient schorl (20-30% X-site vacancy, Fe/(Fe + Mg) 0.8-1), with uniform B-isotope compositions (δ11B -8.7‰ ± 1.5, n = 49) that are indistinguishable from the basement average, suggesting that boron was derived from anatexis of the local basement rocks with no significant shift in isotopic composition. Secondary, hydrothermal tourmaline in the granite has a bimodal B-isotope distribution with one peak at about -9‰, like the main-stage tourmaline, and a second at -2‰. We propose that the tourmaline-rich orbicules formed late in the crystallization history from an immiscible Na-B-Fe-rich hydrous melt. The massive precipitation of orbicular tourmaline nearly exhausted the melt in boron and the shift of δ11B to -2‰ in secondary tourmaline can be explained by Rayleigh fractionation after about 90% B-depletion in the residual fluid.

  18. Seasonal variations in physico-chemical characteristics of water, sediment and soil texture in arid zone mangroves of Kachchh-Gujarat.

    Science.gov (United States)

    Saravanakumar, A; Rajkumar, M; Serebiah, J Sesh; Thivakaran, G A

    2008-09-01

    The present study was carried out to determine the physicochemical characteristics of water and sediment and the textural aspects of sediments in western mangroves of Kachchh-Gujarat, west coast of India, for a period of two years during 1999-2000. Surface water and sediment temperatures varied from 17 degrees C to 37 degrees C and from 18.4 degrees C to 37 degrees C respectively. Tidal amplitude varied from 0.03 m to 3.78 m. Salinity varied from 34.0 to 44 per thousand and the pH in water and sediment ranged between 7.0 and 8.9 and 6.29 and 8.45 respectively. Variation in dissolved oxygen content was from 3.42 to 5.85 ml l(-1). Concentrations of nutrients viz. nitrate (0.23 to 7.26 microM), nitrite (0.04 to 0.87 microM), phosphate (0.13 to 3.12 microM) and reactive silicate (4.23 to 19.02 microM) also varied independently Total organic carbon varied from 0.29% to 2.56% and the total inorganic phosphorus ranged between 0.12 mg g(-1) and 1.97 mg g(-1). Total nitrogen varied from 0.02 mg g(-1) to 1.95 mg g(-1). Sediment textures ranges in terms of % of sand, clay and silt were: 0.26-19.2; 7.6-47 and 47-87.4 respectively in all the 3 stations. The nature of soil texture is characterized by the abundance of silty loam, silty clay and silty clay loam.

  19. Seasonal variations and chemical characterization of ambient PM 10 at residential and industrial sites of an urban region of Kolkata (Calcutta), India

    Science.gov (United States)

    Karar, Kakoli; Gupta, A. K.

    2006-07-01

    simultaneously during the sampling period from the Indian Meteorological Department, Kolkata. A simultaneous meteorological study was performed to assess the influence of air masses by measured meteorological parameters. Winter concentrations of PM 10 and its chemical constituents were mainly higher than in other seasons, irrespective of the monitoring sites. It indicates a longer residence time of particulates in the atmosphere during winter due to low winds and low mixing height. Winter to monsoon ratio for PM 10 is 1.6 and 2.3 for residential and industrial sites, respectively. Summer to monsoon ratio of PM 10 observed in the study period was 1.3 for the residential site, and 1.4 for the industrial site. The higher particulate pollution in the industrial area may be attributed to resuspension of road dust, soil dust, automobile traffic and nearby industrial emissions. Spearman rank correlation coefficient analysis showed an inverse relationship between PM 10 and its chemical constituents with wind speed, temperature, rainfall and relative humidity.

  20. Seasonal and diurnal variations in dust characteristics on the northern slopes of the Tien Shan - Grain-size, mineralogy, chemical signatures and isotope composition of attached nitrate

    Science.gov (United States)

    Schettler, Georg; Shabunin, Anton; Kemnitz, Helga; Knoeller, Kay; Imashev, Sanjar; Rybin, Anatoly; Wetzel, Hans-Ulrich

    2014-07-01

    A dust monitoring program was initiated in the summer of 2010 to (i) improve the informative value of aeolian components of varved lake sediments in Central Asia for palaeoclimatic interpretations, (ii) evaluate the impact of aeolian influx on modern lakes in the region and (iii) obtain data for a future comparison with dust east of the high mountain belt formed by the Alay, Pamir, Tien Shan and Altai mountains. We collected the coarse (>2.5 μm) dust fraction on the northern slopes of the Tien Shan 42°40‧49.69″N, (74°41‧37.36″E, 1740 m asl) using a high-volume slit-impactor at 3-day sampling intervals. We present data on the mineralogical composition, particle-size distribution, soluble salts and nitrate isotope composition of the collected dust. The short-term and seasonal changes in dust concentration and composition are discussed in the context of high temporal resolution measurements of meteorological parameters and particle counts for 31 grain-size bands. Throughout the study period, CaCO3 was a major dust constituent (average particle frequency 14%). Between July 2010 and October 2012, the average content of soluble salts was 10 wt.%; mole percentages of water-leachable anions were 60% NO3, 30% SO4, 10% Cl. Ca was the dominant leachable cation (>90%). The collected dust comprised (i) gypsum which forms pedogenically in the topsoils of arid regions and (ii) secondary gypsum originating from the interaction of sulphuric acid aerosols with CaCO3 in the atmosphere. Variable proportions of (i) and (ii) and the extent of Ca(NO3)2 formation (verified by chemical mass budgets) were documented in the Ca/Sr and Ca/SO4 ratios of the aqueous leachates. The isotopic compositions of the dust nitrate in the majority of the samples clustered between -10 and +10‰ for δ15N[NO3] (VSMOW) and +50 and +100‰ for δ18O[NO3] (Air). The δ18O[NO3] values of a majority of the collected samples exhibited a weak positive correlation with the NO3 load of the collected dust

  1. Orbital forcing of glacial/interglacial variations in chemical weathering within the White Nile basin: stable-isotope and biomarker evidence from Lakes Victoria and Edward

    Science.gov (United States)

    Cockerton, Helen E.; Alayne Street-Perrott, F.; Barker, Philip A.; Leng, Melanie J.; Sloane, Hilary J.; Horstwood, Matthew S. A.; Snelling, Andrea

    2014-05-01

    The continental Si cycle on Quaternary time scales has been largely neglected. Emphasis has been placed on long-term geochemical processes of silicate-rock weathering and the resulting drawdown of atmospheric CO2, rather than on shorter-term biogenic processes occurring along the land-ocean continuum. Si-accumulating plants (notably tropical rainforest hardwoods, savanna and wetland grasses, and Papyrus) and aquatic organisms (such as diatoms and sponges in lakes, rivers and swamps) have the potential to take up, store and recycle significant amounts of Si, thereby modifying the riverine flux of Si to the oceans, the productivity of siliceous marine organisms and the rate of atmospheric CO2 drawdown on an orbital time scale. The main aim of this study was to investigate spatial and temporal patterns of Si cycling along the Nile system during the last 20ka BP. Utilising sediment cores from Lakes Victoria and Edward, coupled measurements of stable Si and O isotopes on cleaned diatom separates were employed to reconstruct millennial-scale variations in biotic Si cycling and palaeohydrology, respectively. Abundance ratios of lipid biomarkers (n-alkanes) were used to track major changes in terrestrial and aquatic ecosystems. The results have been interpreted in the light of multi-isotope analyses (2H,18O,30Si) of modern water samples collected along the courses of the modern White and Blue Niles during both wet- and dry-season conditions. During drier intervals (the Last Glacial Maximum and the late Holocene: high 18Odiatom), Si cycling was greatly reduced. Diminished vegetation cover, reduced biotic rock weathering, a declining soil stock of amorphous silica (ASi) and decreased runoff resulted in reduced dissolved silica (DSi) supply to the lakes in relation to aquatic demand (high 30Sidiatom). In contrast, enhanced monsoon rainfall (low 18Odiatom) during the early to mid-Holocene promoted a substantial increase in terrestrial biomass within the White Nile headwaters

  2. Limnological study of Piraquara river (Upper Iguaçu basin: spatiotemporal variation of physical and chemical variables and watershed zoning

    Directory of Open Access Journals (Sweden)

    Paulo Henrique C. Marques

    2003-06-01

    Full Text Available The Piraquara river basin (Upper Iguaçu River basin - Brazil was studied as an ecological system throughout a complete seasonal cycle, comprising the rainy and dry season. Analyzes of 16 physical and chemical water variables (dissolved oxygen, biochemical oxygen demand, temperature, pH, conductivity, total nitrogen, total phosphorus, ortophosphates, nitrite, nitrate, ammonium, reagent silicate, total suspended solids, chlorophyll - a, flow velocity and depth showed correlations between water composition and watershed physiographic features, and the Principal Component Analysis allowed to evidence spatial gradients and seasonal differences. The sampling points were clustered in patches with homogeneous behavior, according to ecologycal concepts: patch 1, with strong influence of Serra do Mar mountains; patch 2, medium course, under Piraquara Dam influence and patch 3, under wetlands influence. Two main factors of serial discontinuity were identified: the Piraquara dam effect and the influence of wetlands. The watershed zoning based on limnological characteristics seeks to subsidize research and biomonitoring for this public springs area.A bacia hidrográfica do rio Piraquara (Bacia do Alto Rio Iguaçu - PR foi estudada como sistema ecológico ao longo de um ciclo sazonal completo, abrangendo os períodos seco e chuvoso. Análises de 16 variáveis físicas e químicas da água (oxigênio dissolvido, pH, condutividade, DBO5, temperatura, nitrogênio total, fósforo total, ortofosfato, nitrito, nitrato, amônio, silicato, sólidos totais em suspensão, clorofila-a, profundidade e velocidade da corrente demonstraram correlações entre a composição da água e as características fisiográficas da bacia. Os gradiente espaciais e as diferenças sazonais foram evidenciadas pela Análise de Componentes Principais, e a bacia foi dividida em trechos de comportamento homogêneo, sendo identificadas descontinuidades seriais: Trecho 1, com forte influ

  3. Yearly variation and annual cycle of total column ozone over New ...

    Indian Academy of Sciences (India)

    The effect of O3 depletion on night airglow emission of OH(8, 3) line at New Delhi and Halley Bay has been studied. Calculations based on chemical kinetics show that the airglow intensity of OH(8, 3) has also been affected due to the depletion of O3 concentration. The yearly variations and annual cycle of intensities of ...

  4. The Effect of Chemical Composition on Microstructure and Properties of Intercritically Reheated Coarse-Grained Heat-Affected Zone in X70 Steels

    Science.gov (United States)

    Zhu, Zhixiong; Kuzmikova, Lenka; Li, Huijun; Barbaro, Frank

    2013-12-01

    The current study investigates the effect of different levels of Ti, N, and Ti/N ratios on microstructure and properties in the intercritically reheated coarse-grained heat-affected zone (ICCGHAZ) of two-pass submerged arc welds in API 5L grade X70 pipe. Gleeble simulation was employed to reproduce the ICCGHAZ of actual welds. Hardness and Charpy V-notch (CVN) tests were performed on the simulated samples. The microstructure of simulated ICCGHAZ was characterized by optical microscopy and scanning electron microscopy (SEM). LePera color etching technique was employed to identify and quantify the martensitic-austenitic (M-A) constituent. Results show that the simulated ICCGHAZ exhibited extremely low toughness, but in the studied range of Ti and N, there was no correlation with Ti/N ratio. The beneficial effect of near-stoichiometric Ti/N ratio observed in coarse-grained heat-affected zone (CGHAZ) did not translate to ICCGHAZ. This was because of the negative effect of the blocky M-A constituent formed on prior austenite grain boundaries.

  5. An Investigation into the Physico-chemical Factors Affecting the Abundance and Diversity of Aquatic Insects in Organically Manured Aquadams and Their Utilization by Oreochromis mossambicus (Perciformes: Cichlidae).

    Science.gov (United States)

    Rapatsa, M M; Moyo, N A G

    2015-08-01

    The interaction between the fish Oreochromis mossambicus (Percifomes: Cichlidae) and aquatic insects after application of chicken, cow, and pig manure was studied in 7,000-liter plastic aquadams. Principal component analysis showed that most of the variation in water quality after application of manure was accounted for by potassium, nitrogen, dissolved oxygen, phosphate, and alkalinity. Canonical correspondence analysis showed that Gyrinidae, Elminidae, Hydrophilidae, Hydraenidae, and Athericidae were associated with high nutrient levels (nitrogen, phosphorus, and potassium) characteristic of the chicken manure. However, the most abundant aquatic insects Gerridae, Notonectidae, and Culicidae were close to the centre of the ordination and not defined by any nutrient gradient. The Shannon-Wiener diversity was highest in the aquadams treated with chicken manure. The most frequently occurring aquatic insects in the diet of O. mossambicus were culicid mosquitoes in all the treatments. However, in the laboratory, Chironomidae were the most preferred because they lacked refuge. Notonectidae and Gerridae were not recorded in the diet of O. mossambicus despite their abundance. This may be because of their anti-predation strategies. Laboratory experiments showed that Notonectidae, Gyrinidae, and Gerridae fed on Chironomidae and Culicidae. This implies that aquatic predatory insects competed for food with O. mossambicus. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  6. Species and life-history affects the utility of otolith chemical composition to determine natal stream-of-origin in Pacific salmon

    Science.gov (United States)

    Zimmerman, Christian E.; Swanson, Heidi K.; Volk, Eric C.; Kent, Adam J.R.

    2013-01-01

    To test the utility of otolith chemical composition as a tool for determining the natal stream of origin for salmon, we examined water chemistry and otoliths of juvenile and adult Chum Salmon Oncorhynchus keta and Coho Salmon O. kisutch from three watersheds (five rivers) in the Norton Sound region of Alaska. The two species are characterized by different life histories: Coho Salmon rear in freshwater for up to 3 years, whereas Chum Salmon emigrate from freshwater shortly after emergence. We used laser ablation (LA) inductively coupled plasma (ICP) mass spectrometry (MS) to quantify element: Ca ratios for Mg, Mn, Zn, Sr, and Ba, and we used multicollector LA-ICP-MS to determine 87Sr:86Sr ratios in otolith regions corresponding to the period of freshwater residence. Significant differences existed in both water and otolith elemental composition, suggesting that otolith composition could be used to discriminate the natal origin of Coho Salmon and Chum Salmon but only when 87Sr:86Sr ratios were included in the discriminant function analyses. The best discriminant model included 87Sr:86Sr ratios, and without 87Sr:86Sr ratios it was difficult to discriminate among watersheds and rivers. Classification accuracy was 80% for Coho Salmon and 68% for Chum Salmon, indicating that this method does not provide sufficient sensitivity to estimate straying rates of Pacific salmon at the scale we studied.

  7. Long-term presence of tree species but not chemical diversity affect litter mixture effects on decomposition in a neotropical rainforest.

    Science.gov (United States)

    Barantal, Sandra; Roy, Jacques; Fromin, Nathalie; Schimann, Heidy; Hättenschwiler, Stephan

    2011-09-01

    Plant litter diversity effects on decomposition rates are frequently reported, but with a strong bias towards temperate ecosystems. Altered decomposition and nutrient recycling with changing litter diversity may be particularly important in tree species-rich tropical rainforests on nutrient-poor soils. Using 28 different mixtures of leaf litter from 16 Amazonian rainforest tree species, we tested the hypothesis that litter mixture effects on decomposition increase with increasing functional litter diversity. Litter mixtures and all single litter species were exposed in the field for 9 months using custom-made microcosms with soil fauna access. In order to test the hypothesis that the long-term presence of tree species contributing to the litter mixtures increases mixture effects on decomposition, microcosms were installed in a plantation at sites including the respective tree species composition and in a nearby natural forest where these tree species are absent. We found that mixture decomposition deviated from predictions based on single species, with predominantly synergistic effects. Functional litter diversity, defined as either richness, evenness, or divergence based on a wide range of chemical traits, did not explain the observed litter mixture effects. However, synergistic effects in litter mixtures increased with the long-term presence of tree species contributing to these mixtures as the home field advantage hypothesis assumes. Our data suggest that complementarity effects on mixed litter decomposition may emerge through long-term interactions between aboveground and belowground biota.

  8. Small relief shape variations influence spatial variability of soil chemical attributes Pequenas variações das formas de relevo influenciam a variabilidade espacial de atributos químicos do solo

    Directory of Open Access Journals (Sweden)

    Zigomar Menezes de Souza

    2006-04-01

    Full Text Available Soils with small variations in relief and under the same management system present differentiated spatial variabilities of their attributes. This variability is a function of soil position in the landscape, even if the relief has little expression. The aim of this work was to investigate the effects of relief shape and depth on spatial variability of soil chemical attributes in a Typic Hapludox cultivated with sugar cane at two landscape compartments. Soil samples were collected in the intercrossing points of a grid, in the traffic line, at 0-0.2 m and 0.6-0.8 m depths, comprising a set of 100 georeferenced points. The spatial variabilities of pH, P, K, Ca, Mg, cation exchange capacity and base saturation were quantified. Small relief shape variations lead to differentiated variability in soil chemical attributes as indicated by the dependence on pedoform found for chemical attributes at both 0-0.2 m and 0.6-0.8 m depths. Because of the higher variability, it is advisable to collect large number of samples in areas with concave and convex shapes. Combining relief shapes and geostatistics allows the determination of areas with different spatial variability for soil chemical attributes.Solos submetidos ao mesmo sistema de manejo em locais com pequena variação de relevo, manifestam variabilidade espacial diferenciada de seus atributos. Esta variabilidade é condicionada pela posição dos solos na paisagem ou no declive, mesmo que o relevo seja de pequena expressão. O estudo teve como objetivo avaliar a influência da forma do relevo na variabilidade espacial de atributos químicos em um latossolo cultivado com cana-de-açúcar em dois compartimentos da paisagem. Os solos foram amostrados nos pontos de cruzamento de uma malha, com intervalos regulares de 10 m, perfazendo um total de 100 pontos, nas profundidades de 0-0,2 m e 0,6-0,8 m. Foi avaliado a variabilidade espacial do pH, fósforo (P, potássio (K, cálcio (Ca, magnésio (Mg, acidez

  9. Effect of different chemical bonds in pegylation of zinc protoporphyrin that affects drug release, intracellular uptake, and therapeutic effect in the tumor.

    Science.gov (United States)

    Tsukigawa, Kenji; Nakamura, Hideaki; Fang, Jun; Otagiri, Masaki; Maeda, Hiroshi

    2015-01-01

    Pegylated zinc protoporphyrin (PEG-ZnPP) is a water-soluble inhibitor of heme oxygenase-1. In this study, we prepared two types of PEG-ZnPP conjugates with different chemical bonds between PEG and ZnPP, i.e., ester bonds and ether bonds, where both conjugates also contain amide bonds. Cleavability of these bonds in vitro and in vivo, especially cancer tissue, and upon intracellular uptake, was investigated in parallel with biological activities of the conjugates. Each conjugate showed different cleavability by plasma esterases and tumor proteases, as revealed by HPLC analyses. PEG-ZnPP with ester bond (esPEG-ZnPP) was more sensitive than PEG-ZnPP with ether bond (etPEG-ZnPP) for cleavage of PEG chains. etPEG-ZnPP showed no cleavage of PEG chains and had lower intracellular uptake and antitumor activity than did esPEG-ZnPP. The degradation of esPEG-ZnPP appeared to be facilitated by both serine and cysteine proteases in tumor tissues, whereas it was significantly slower in normal organs except the liver. Depegylated products such as free ZnPP had higher intracellular uptake than did intact PEG-ZnPP. We also studied hydrolytic cleavage by blood plasma of different animal species; mouse plasma showed the fastest cleavage whereas human plasma showed the slowest. These results suggest that ester-linked conjugates manifest more efficient cleavage of PEG, and greater yield of the active principle from the conjugates in tumor tissues than in normal tissues. More efficient intracellular uptake and thus an improved therapeutic effect with ester-linked conjugates are thus anticipated with fain stability, particularly in human blood. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Repeated applications of compost and manure mainly affect the size and chemical nature of particulate organic matter in a loamy soil after 8 years

    Science.gov (United States)

    Peltre, Clement; Dignac, Marie-France; Doublet, Jeremy; Plante, Alain; Houot, Sabine

    2013-04-01

    Land application of exogenous organic matter (EOM) of residual origin can help to maintain or increase soil organic carbon (SOC) stocks. However, it remains necessary to quantify and predict the soil C accumulation and to determine under which form the C accumulates. Changes to the chemical composition of soil organic matter (SOM) after repeated applications of composts and farmyard manure were investigated in a field experiment (Qualiagro experiment, Ile-de-France) after 8 years of applications of green waste and sludge compost (GWS), municipal solid waste compost (MSW), biowaste compost (BIOW) or farmyard manure (FYM). The soil was fractionated into particulate organic matter >50 µm (POM), a heavy fraction >50 µm and a 0-50 µm fraction demineralized with hydrofluoric acid (HF). Repeated EOM applications significantly increased total SOC stocks, the C amount in the POM fraction and to a less extent in the 0-50 µm fraction compared to the reference treatment. Compost applications accumulated C preferentially under the form of coarse organic matter of size >50 µm, whereas the FYM accumulated similar C proportions of size >50 µm and 0-50 µm, which was attributed to the presence in the FYM of a fraction of labile C stimulating microbial activity and producing humified by-products together with a fraction of stabilized C directly alimenting the humified fraction of SOC. Pyrolysis-GC/MS and DRIFT spectroscopy revealed enrichment in lignin in the POM fractions of amended soils with GWS, BIOW and FYM. In the soil receiving MSW compost, the pyrolysate of the POM fraction revealed the presence of plastics originating from the MSW compost. A lower C mineralization during laboratory incubation was found for the POM fractions of amended soils compared with the POM from reference soil. This feature was related to a lower ratio of (furfural+acetic acid) / pyrole pyrolysis products in POM of amended vs. reference plots, indicating a higher degree of recalcitrance.. The POM

  11. Iodine and Selenium Biofortification with Additional Application of Salicylic Acid Affects Yield, Selected Molecular Parameters and Chemical Composition of Lettuce Plants (Lactuca sativa L. var. capitata

    Directory of Open Access Journals (Sweden)

    Sylwester Smoleń

    2016-10-01

    Full Text Available Iodine (I and selenium (Se are included in the group of beneficial elements. They both play important roles in humans and other animals, particularly in the regulation of thyroid functioning. A substantial percentage of people around the world suffer from health disorders related to the deficiency of these elements in the diet. Salicylic acid (SA is a compound similar to phytohormones and is known to improve the efficiency of I biofortification of plants. The influence of SA on Se enrichment of plants has not, however, been recognised together with its effect on simultaneous application of I and Se to plants. Two-year studies (2014–2015 were conducted in a greenhouse with hydroponic cultivation of lettuce in an NFT (nutrient film technique system. They included the application of I (as KIO3, Se (as Na2SeO3 and SA into the nutrient solution. KIO3 was used at a dose of 5 mg I•dm-3 (i.e., 39.4 µM I, while Na2SeO3 was 0.5 mg Se•dm-3 (i.e., 6.3 µM Se. SA was introduced at three doses: 0.1, 1.0 and 10.0 mg∙dm-3 nutrient solutions, equivalent to 0.724 µM, 7.24 µM and 72.4 µM SA, respectively. The tested combinations were as follows: 1. control, 2. I + Se, 3. I + Se + 0.1 mg SA∙dm-3, 4. I + Se + 1.0 mg SA∙dm-3 and 5. I + Se + 10.0 mg SA∙dm-3. The applied treatments had no significant impact on lettuce biomass (leaves and roots. Depending on the dose, a diverse influence of SA was noted with respect to the efficiency of I and Se biofortification; chemical composition of leaves; and mineral nutrition of lettuce plants, including the content of macro- and microelements and selenocysteine methyltransferase (SMT gene expression. SA application at all tested doses comparably increased the level of selenomethionine (SeMet and decreased the content of SA in leaves.

  12. Experiencing variation

    DEFF Research Database (Denmark)

    Kobayashi, Sofie; Berge, Maria; Grout, Brian William Wilson

    2017-01-01

    This study contributes towards a better understanding of learning dynamics in doctoral supervision by analysing how learning opportunities are created in the interaction between supervisors and PhD students, using the notion of experiencing variation as a key to learning. Empirically, we have bas...... were discussed, created more complex patterns of variation. Both PhD students and supervisors can learn from this. Understanding of this mechanism that creates learning opportunities can help supervisors develop their competences in supervisory pedagogy....

  13. Chemical properties of volcanic soil affected by seven-year rotations Propiedades químicas del suelo volcánico afectado por rotaciones de siete años

    Directory of Open Access Journals (Sweden)

    Juan Hirzel

    2011-06-01

    Full Text Available Long-term crop rotation systems can benefit soil chemical-physical properties and crop productivity. The lack of information on the effect of long-term crop rotations on soil chemical-physical properties for volcanic soils in Chile could restrict reaping real benefits, and make it difficult to take agricultural management decisions, which could lead to possible negative consequences on some soil chemical-physical properties and the environment. The development of information associated with the effect on soil chemical-physical properties with respect to long-term rotation systems and their fertilization management contribute to improving agronomic management decisions for these soils. A study was carried out to assess the effect of six rotation systems replicating fertilization management used by farmers, especially N and P application, and eventually low rates of K, Ca and Mg on soil chemical properties in a volcanic soil after 7 yr in Central South Chile. Affected chemical properties were pH, inorganic N, and available K, along with a general decrease of pH related to fertilization used, which was insufficient in Ca, K, and Mg. Moreover, this soil exhibited high P adsorption capacity (90.2 to 97.5%. Hence, crop rotations that included pasture legumes and crops with high nutrient inputs such as sugar beet (Beta vulgaris L. generated a less negative effect on soil chemical properties. This study indicates that fertilization management in crop rotation systems must consider the input and output nutrient balances to prevent the negative effect on some soil chemical properties.Los sistemas de rotación de cultivos de largo plazo pueden tener varios beneficios sobre las propiedades físico-químicas del suelo y productividad de los cultivos. La falta de información sobre el efecto de rotaciones de largo plazo en las propiedades físico-químicas para suelos volcánicos en Chile podría limitar la obtención de beneficios reales, dificultando

  14. Chemical Emergencies

    Science.gov (United States)

    When a hazardous chemical has been released, it may harm people's health. Chemical releases can be unintentional, as in the case of an ... the case of a terrorist attack with a chemical weapon. Some hazardous chemicals have been developed by ...

  15. Variational analysis

    CERN Document Server

    Rockafellar, R Tyrrell

    1998-01-01

    From its origins in the minimization of integral functionals, the notion of 'variations' has evolved greatly in connection with applications in optimization, equilibrium, and control. It refers not only to constrained movement away from a point, but also to modes of perturbation and approximation that are best describable by 'set convergence', variational convergence of functions and the like. This book develops a unified framework and, in finite dimension, provides a detailed exposition of variational geometry and subdifferential calculus in their current forms beyond classical and convex analysis. Also covered are set-convergence, set-valued mappings, epi-convergence, duality, maximal monotone mappings, second-order subderivatives, measurable selections and normal integrands. The changes in this 3rd printing mainly concern various typographical corrections, and reference omissions that came to light in the previous printings. Many of these reached the authors' notice through their own re-reading, that of th...

  16. Variational principles

    CERN Document Server

    Moiseiwitsch, B L

    2004-01-01

    This graduate-level text's primary objective is to demonstrate the expression of the equations of the various branches of mathematical physics in the succinct and elegant form of variational principles (and thereby illuminate their interrelationship). Its related intentions are to show how variational principles may be employed to determine the discrete eigenvalues for stationary state problems and to illustrate how to find the values of quantities (such as the phase shifts) that arise in the theory of scattering. Chapter-by-chapter treatment consists of analytical dynamics; optics, wave mecha

  17. Intraspecific genetic variation and species coexistence in plant communities.

    Science.gov (United States)

    Ehlers, Bodil K; Damgaard, Christian F; Laroche, Fabien

    2016-01-01

    Many studies report that intraspecific genetic variation in plants can affect community composition and coexistence. However, less is known about which traits are responsible and the mechanisms by which variation in these traits affect the associated community. Focusing on plant-plant interactions, we review empirical studies exemplifying how intraspecific genetic variation in functional traits impacts plant coexistence. Intraspecific variation in chemical and architectural traits promotes species coexistence, by both increasing habitat heterogeneity and altering competitive hierarchies. Decomposing species interactions into interactions between genotypes shows that genotype × genotype interactions are often intransitive. The outcome of plant-plant interactions varies with local adaptation to the environment and with dominant neighbour genotypes, and some plants can recognize the genetic identity of neighbour plants if they have a common history of coexistence. Taken together, this reveals a very dynamic nature of coexistence. We outline how more traits mediating plant-plant interactions may be identified, and how future studies could use population genetic surveys of genotype distribution in nature and methods from trait-based ecology to better quantify the impact of intraspecific genetic variation on plant coexistence. © 2016 The Author(s).

  18. Genetic architecture of natural variation in cuticular hydrocarbon composition in Drosophila melanogaster.

    Science.gov (United States)

    Dembeck, Lauren M; Böröczky, Katalin; Huang, Wen; Schal, Coby; Anholt, Robert R H; Mackay, Trudy F C

    2015-11-14

    Insect cuticular hydrocarbons (CHCs) prevent desiccation and serve as chemical signals that mediate social interactions. Drosophila melanogaster CHCs have been studied extensively, but the genetic basis for individual variation in CHC composition is largely unknown. We quantified variation in CHC profiles in the D. melanogaster Genetic Reference Panel (DGRP) and identified novel CHCs. We used principal component (PC) analysis to extract PCs that explain the majority of CHC variation and identified polymorphisms in or near 305 and 173 genes in females and males, respectively, associated with variation in these PCs. In addition, 17 DGRP lines contain the functional Desat2 allele characteristic of African and Caribbean D. melanogaster females (more 5,9-C27:2 and less 7,11-C27:2, female sex pheromone isomers). Disruption of expression of 24 candidate genes affected CHC composition in at least one sex. These genes are associated with fatty acid metabolism and represent mechanistic targets for individual variation in CHC composition.

  19. Variación de compuestos químicos en hojas de poblaciones de Drimys spp. (Magnoliophyta: Winteraceae en Chile Variation of chemical compounds in leaves of Drimys spp. (Magnoliophyta: Winteraceae populations in Chile

    Directory of Open Access Journals (Sweden)

    DIEGO MUÑOZ-CONCHA

    2004-03-01

    Soxhlet extraction (terpenes, and spectrophotometry (flavonoids. Mean concentrations of 0.5 mL 100 g-1 for essential oils, 7.1 % for terpenes and 1.8 % for flavonoids in leaves (dry mass were determined. Despite the great variation found, significant differences among populations were detected in concentrations of all groups of chemical compounds studied. Populations from the central region of Chile presented the highest values of essential oils (0.68 mL 100 g-1 in Huerta de Maule population, terpenes, and flavonoids (9.47 and 2.37 %, respectively, both in the Pangal population. The southernmost population, located in Chiloé Island, showed the lowest values for the three groups of compounds: 0.22 mL 100 g-1 for essential oils, 3.36 % for terpenes and 1.21 % for flavonoids. D. winteri and D. andina populations from the IX region, geographically close to each other, had different concentrations of essential oils and flavonoids. It is concluded that different Drimys populations actually contain different quantities of essential oils, terpenes, and flavonoids

  20. [Chemical analysis of the integument and digestive gland of Crangon crangon (Linné) (Crustacea, Decapoda) by x ray spectography. Quantitative variations in the elements of calcium, phosphorus, sulfur, and magnesium during the intermolt cycle].

    Science.gov (United States)

    Chassard-Bouchaud, C

    1977-03-14

    Electron probe microanalysis is a very suitable method for qualitative and quantitative analysis of calcium, phosphorus, sulfur and magnesium occurring within integument and digestive gland; variations related to intermolt cycle can be compared.

  1. The chemical juggernaut.

    Science.gov (United States)

    Cadbury, D

    1997-01-01

    Man-made chemicals pervade and support every aspect of modern living. The chemical industry has become such a powerful force in the global economy, sales of synthetic chemicals and products derived from them constitute well in excess of a third of the world's gross national product. But, these man-made chemicals are also 'elixirs of death,' the symbol of human destruction. Laboratory tests have shown that a number of chemicals in common use possess a remarkable property: they can weakly mimic or modify the action of human hormones. It has been proven that some chemicals found in plastics, pesticides, and industrial products are weakly estrogenic, modifying the action of the female hormone. In addition, other chemicals affect the male hormones, androgens, or anti-androgens; others are thought to target different hormone systems, such as thyroid and adrenal glands. Many research studies are being conducted to establish the impact of chemicals on human health. Of special concern are the rising incidence of testicular cancer, decline in human sperm counts, and the sharp rise of breast cancer. In conclusion, although there is a worldwide debate on the effects of chemical exposure on humans, the significance of findings for human health, concerning testicular and breast cancer, are still unknown. An international treaty is called for to control the use of the persistent hormonally active chemicals.

  2. Affect Regulation

    DEFF Research Database (Denmark)

    Pedersen, Signe Holm; Poulsen, Stig Bernt; Lunn, Susanne

    2014-01-01

    Gergely and colleagues’ state that their Social Biofeedback Theory of Parental Affect Mirroring” can be seen as a kind of operationalization of the classical psychoanalytic concepts of holding, containing and mirroring. This article examines to what extent the social biofeedback theory of parental...... affect mirroring may be understood as a specification of these concepts. It is argued that despite similarities at a descriptive level the concepts are embedded in theories with different ideas of subjectivity. Hence an understanding of the concept of affect regulation as a concretizisation...... and specification of the classical concepts dilutes the complexity of both the concept of affect regulation and of the classical concepts....

  3. The Role of Diet in Shaping the Chemical Signal Design of Lacertid Lizards.

    Science.gov (United States)

    Baeckens, Simon; García-Roa, Roberto; Martín, José; Van Damme, Raoul

    2017-09-01

    Lizards communicate with others via chemical signals, the composition of which may vary among species. Although the selective pressures and constraints affecting chemical signal diversity at the species level remain poorly understood, the possible role of diet has been largely neglected. The chemical signals of many lizards originate from the femoral glands that exude a mixture of semiochemicals, and may be used in a variety of contexts. We analyzed the lipophilic fraction of the glandular secretions of 45 species of lacertid lizard species by gas chromatography/mass spectrometry. The proportions of nine major chemical classes (alcohols, aldehydes, fatty acids, furanones, ketones, steroids, terpenoids, tocopherols and waxy esters), the relative contributions of these different classes ('chemical diversity'), and the total number of different lipophilic compounds ('chemical richness') varied greatly among species. We examined whether interspecific differences in these chemical variables could be coupled to interspecific variation in diet using data from the literature. In addition, we compared chemical signal composition among species that almost never, occasionally, or often eat plant material. We found little support for the hypothesis that the chemical profile of a given species' secretion depends on the type of food consumed. Diet breadth did not correlate with chemical diversity or richness. The amount of plants or ants consumed did not affect the relative contribution of any of the nine major chemical classes to the secretion. Chemical diversity did not differ among lizards with different levels of plant consumption; however, chemical richness was low in species with an exclusive arthropod diet, suggesting that incorporating plants in the diet enables lizards to increase the number of compounds allocated to secretions, likely because a (partly) herbivorous diet allows them to include compounds of plant origin that are unavailable in animal prey. Still, overall

  4. Chemical use

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is a summary of research and activities related to chemical use on Neal Smith National Wildlife Refuge between 1992 and 2009. The chemicals used on the Refuge...

  5. Chemicals in material cycles

    DEFF Research Database (Denmark)

    Pivnenko, Kostyantyn; Eriksson, Eva; Astrup, Thomas Fruergaard

    2015-01-01

    Material recycling has been found beneficial in terms of resource and energy performance and is greatly promoted throughout the world. A variety of chemicals is used in materials as additives and data on their presence is sparse. The present work dealt with paper as recyclable material...... and diisobutyl phthalate (DiBP) as chemical in focus. The results showed variations, between 0.83 and 32 μg/g, in the presence of DiBP in Danish waste paper and board and potential accumulation due to recycling....

  6. The activity of TcCYS4 modified by variations in pH and temperature can affect symptoms of witches' broom disease of cocoa, caused by the fungus Moniliophthora perniciosa.

    Science.gov (United States)

    Freitas, Ana Camila Oliveira; Souza, Cristiane Ferreira; Monzani, Paulo Sérgio; Garcia, Wanius; de Almeida, Alex Alan Furtado; Costa, Marcio Gilberto Cardoso; Pirovani, Carlos Priminho

    2015-01-01

    The phytocystatins regulate various physiological processes in plants, including responses to biotic and abiotic stresses, mainly because they act as inhibitors of cysteine proteases. In this study, we have analyzed four cystatins from Theobroma cacao L. previously identified in ESTs libraries of the interaction with the fungus Moniliophthora perniciosa and named TcCYS1, TcCYS2, TcCYS3 and TcCYS4. The recombinant cystatins were purified and subjected to the heat treatment, at different temperatures, and their thermostabilities were monitored using their ability to inhibit papain protease. TcCYS1 was sensitive to temperatures above 50°C, while TcCYS2, TcCYS3, and TcCYS4 were thermostable. TcCYS4 presented a decrease of inhibitory activity when it was treated at temperatures between 60 and 70°C, with the greater decrease occurring at 65°C. Analyses by native gel electrophoresis and size-exclusion chromatography showed that TcCYS4 forms oligomers at temperatures between 60 and 70°C, condition where reduction of inhibitory activity was observed. TcCYS4 oligomers remain stable for up to 20 days after heat treatment and are undone after treatment at 80°C. TcCYS4 presented approximately 90% of inhibitory activity at pH values between 5 and 9. This protein treated at temperatures above 45°C and pH 5 presented reduced inhibitory activity against papain, suggesting that the pH 5 enhances the formation of TcCYS4 oligomers. A variation in the titratable acidity was observed in tissues of T. cacao during the symptoms of witches' broom disease. Our findings suggest that the oligomerization of TcCYS4, favored by variations in pH, is an endergonic process. We speculate that this process can be involved in the development of the symptoms of witches' broom disease in cocoa.

  7. Impact of physical and chemical parameters on the hydroxyapatite nanopowder synthesized by chemical precipitation method

    Science.gov (United States)

    Thu Trang Pham, Thi; Phuong Nguyen, Thu; Pham, Thi Nam; Phuong Vu, Thi; Tran, Dai Lam; Thai, Hoang; Thanh Dinh, Thi Mai

    2013-09-01

    In this paper, the synthesis of hydroxyapatite (HAp) nanopowder was studied by chemical precipitation method at different values of reaction temperature, settling time, Ca/P ratio, calcination temperature, (NH4)2HPO4 addition rate, initial concentration of Ca(NO3)2 and (NH4)2HPO4. Analysis results of properties, morphology, structure of HAp powder from infrared (IR) spectra, x-ray diffraction (XRD), energy dispersive x-ray (EDX) spectra and scanning electron microscopy (SEM) indicated that the synthesized HAp powder had cylinder crystal shape with size less than 100 nm, single-phase structure. The variation of the synthesis conditions did not affect the morphology but affected the size of HAp crystals.

  8. The Activity of TcCYS4 Modified by Variations in pH and Temperature Can Affect Symptoms of Witches’ Broom Disease of Cocoa, Caused by the Fungus Moniliophthora perniciosa

    Science.gov (United States)

    Freitas, Ana Camila Oliveira; Souza, Cristiane Ferreira; Monzani, Paulo Sérgio; Garcia, Wanius; de Almeida, Alex Alan Furtado; Costa, Marcio Gilberto Cardoso; Pirovani, Carlos Priminho

    2015-01-01

    The phytocystatins regulate various physiological processes in plants, including responses to biotic and abiotic stresses, mainly because they act as inhibitors of cysteine proteases. In this study, we have analyzed four cystatins from Theobroma cacao L. previously identified in ESTs libraries of the interaction with the fungus Moniliophthora perniciosa and named TcCYS1, TcCYS2, TcCYS3 and TcCYS4. The recombinant cystatins were purified and subjected to the heat treatment, at different temperatures, and their thermostabilities were monitored using their ability to inhibit papain protease. TcCYS1 was sensitive to temperatures above 50°C, while TcCYS2, TcCYS3, and TcCYS4 were thermostable. TcCYS4 presented a decrease of inhibitory activity when it was treated at temperatures between 60 and 70°C, with the greater decrease occurring at 65°C. Analyses by native gel electrophoresis and size-exclusion chromatography showed that TcCYS4 forms oligomers at temperatures between 60 and 70°C, condition where reduction of inhibitory activity was observed. TcCYS4 oligomers remain stable for up to 20 days after heat treatment and are undone after treatment at 80°C. TcCYS4 presented approximately 90% of inhibitory activity at pH values between 5 and 9. This protein treated at temperatures above 45°C and pH 5 presented reduced inhibitory activity against papain, suggesting that the pH 5 enhances the formation of TcCYS4 oligomers. A variation in the titratable acidity was observed in tissues of T. cacao during the symptoms of witches’ broom disease. Our findings suggest that the oligomerization of TcCYS4, favored by variations in pH, is an endergonic process. We speculate that this process can be involved in the development of the symptoms of witches’ broom disease in cocoa. PMID:25830226

  9. [Chemical weapons and chemical terrorism].

    Science.gov (United States)

    Nakamura, Katsumi

    2005-10-01

    Chemical Weapons are kind of Weapons of Mass Destruction (WMD). They were used large quantities in WWI. Historically, large quantities usage like WWI was not recorded, but small usage has appeared now and then. Chemical weapons are so called "Nuclear weapon for poor countrys" because it's very easy to produce/possession being possible. They are categorized (1) Nerve Agents, (2) Blister Agents, (3) Cyanide (blood) Agents, (4) Pulmonary Agents, (5) Incapacitating Agents (6) Tear Agents from the viewpoint of human body interaction. In 1997 the Chemical Weapons Convention has taken effect. It prohibits chemical weapons development/production, and Organization for the Prohibition of Chemical Weapons (OPCW) verification regime contributes to the chemical weapons disposal. But possibility of possession/use of weapons of mass destruction by terrorist group represented in one by Matsumoto and Tokyo Subway Sarin Attack, So new chemical terrorism countermeasures are necessary.

  10. Genetic Variation of Growth and Disease Resistance Traits in Open-Pollinated Provenance-Progeny Trials of Falcataria moluccana Growing on Two Rust-Affected Sites at Age-18 Months

    Directory of Open Access Journals (Sweden)

    Liliana Baskorowati

    2017-04-01

    Full Text Available Two Falcataria moluccana (sengon progeny trials, incorporating 100 different families from 12 provenances growing on two highly gall rust (Uromycladium falcatarium prone sites were used to estimate genetic parameters and potentially identify rust-resistant material. Analysis was performed to assess provenance- and family-level survival, rust incidence, and growth at the two progeny trials. Height, diameter, survival, and rust incidence was measured at two progeny trials at 18 months-of-age located at Jember and Lumajang, East Java. Rust incidence at the two trial sites was severe, with only 39% overall survival (35% and 43% at Jember and Lumajang, repectively. The analysis revealed significant genetic variation at the provenance level for survival, rust incidence, and growth. No statistically meaningful narrow-sense heritability of these traits was indicated, though this is probably reflective of the inadequate within-family replication and effects associated with uneven stocking resulting from rust-induced mortality. Significant genotype-by environment (provenance-by-site interaction was also indicated, though the performance of some of the best- and worst-performing provenances was relatively stable, allowing recommendations of suitable provenances for further testing on rust-prone sites

  11. Seasonal variations in physicochemical profiles of Guduchi Satva (starchy substance from Tinospora cordifolia [Willd.] Miers

    Directory of Open Access Journals (Sweden)

    Rohit Sharma

    2013-01-01

    Full Text Available Guduchi Satva (GS, the starchy material extracted from the Guduchi stem is well-known Ayurvedic single drug formulation having a wide range of therapeutic utility. Species of the plant, stem size, collection time, season and maturity of the plant may affect the yield and physico-chemical profile of GS. However, published data on such variations is lacking. Considering this, present study is planned to screen seasonal variations in physico-chemical profile of GS. 18 batches of GS were prepared in six different seasons (3 batches in each season and findings were systematically recorded. The obtained Satva was further subjected to relevant physico-chemical parameters. Principal component analysis method was adopted to analyze variations. Maximum yield of Satva was obtained in Shishira Ritu(January-February while the minimum in Grishma (May-June. Variation in taste and color was found in Satva prepared in Varsha Ritu. All functional groups were found to be same in each season. Total alkaloidal contents found bit higher in Varsha and Vasanta. More residual x-variance in alcohol soluble extract and more leverage were observed in water soluble extract due to impact of seasonal spells.

  12. Chemical Composition

    Science.gov (United States)

    May, Willie; Cavanagh, Richard; Turk, Gregory; Winchester, Michael; Travis, John; Smith, Melody; Derose, Paul; Choquette, Steven; Kramer, Gary; Sieber, John; Greenberg, Robert; Lindstrom, Richard; Lamaze, George; Zeisler, Rolf; Schantz, Michele; Sander, Lane; Phinney, Karen; Welch, Michael; Vetter, Thomas; Pratt, Kenneth; Scott, John; Small, John; Wight, Scott; Stranick, Stephan

    Measurements of the chemical compositions of materials and the levels of certain substances in them are vital when assessing and improving public health, safety and the environment, are necessary to ensure trade equity, and are required when monitoring and improving industrial products and services. Chemical measurements play a crucial role in most areas of the economy, including healthcare, food and nutrition, agriculture, environmental technologies, chemicals and materials, instrumentation, electronics, forensics, energy, and transportation.

  13. Chemical oceanography

    National Research Council Canada - National Science Library

    Millero, F.J

    1996-01-01

    Chemical Oceanography presents a comprehensive examination of the chemistry of oceans through discussions of such topics as descriptive physical oceanography, the composition of seawater and the major...

  14. Affective Networks

    OpenAIRE

    Jodi Dean

    2010-01-01

    This article sets out the idea of affective networks as a constitutive feature of communicative capitalism. It explores the circulation of intensities in contemporary information and communication networks, arguing that this circulation should be theorized in terms of the psychoanalytic notion of the drive. The article includes critical engagements with theorists such as Guy Debord, Jacques Lacan, Tiziana Terranova, and Slavoj Zizek.

  15. Affective Urbanism

    DEFF Research Database (Denmark)

    Samson, Kristine

    Urban design and architecture are increasingly used as material and affective strategies for setting the scene, for manipulation and the production of urban life: The orchestration of atmospheres, the framing and staging of urban actions, the programming for contemplation, involvement, play...

  16. Atributos químicos do solo e produtividade de videiras alterados pelo manejo de coberturas verdes na Serra Gaúcha Soil chemical properties and grapevine yield affected by cover crop management in Serra Gaucha, Southern Brazil

    Directory of Open Access Journals (Sweden)

    Jaqueline Dalla Rosa

    2009-02-01

    Full Text Available O manejo do solo pode interferir na disponibilidade de nutrientes e na produtividade de frutos. O objetivo deste estudo foi avaliar o efeito de formas de manejo da fitomassa de diferentes espécies de plantas de cobertura verde sobre características químicas do solo, relacionadas à matéria orgânica e à disponibilidade de nutrientes, e sobre a produtividade de uva. O experimento foi realizado na Embrapa Uva e Vinho, em Bento Gonçalves, RS, sobre um Cambissolo Háplico, num parreiral implantado em 1989, com os cultivares Niágara Branca e Niágara Rosada, no sistema de latada. Os tratamentos testados foram implantados em 2002 e consistiram em três coberturas vegetais: vegetação espontânea, aveia-preta e consórcio de trevo-branco + trevo-vermelho + azevém; e dois sistemas de manejo: dessecado com herbicida e roçado, os quais foram realizados no outono, previamente à ressemeadura das espécies. O delineamento experimental foi de blocos ao acaso com três repetições. Os atributos químicos indicadores da acidez e da disponibilidade de nutrientes no solo foram pouco influenciados pelas espécies de cobertura. A dessecação das plantas aumentou os teores de Ca e Mg trocáveis, P disponível e C orgânico total em relação ao manejo roçado. A produtividade de uva nas safras de 2004 e 2006 foi baixa em relação ao potencial dos cultivares, possivelmente por restrições climáticas, contudo foi maior quando se utilizou a aveia como planta de cobertura do que com o consórcio de plantas.Soil management can have effects on nutrient availability and fruit yield. The objective of this study was to evaluate the effect of phytomass management forms of different cover crop species on soil chemical properties related to organic matter, nutrient availability, and on grapevine yields. The experiment was carried out in Embrapa Uva e Vinho, in Bento Gonçalves, RS, in Southern Brazil, on a Haplic Cambissol, in a vineyard established in 1989

  17. Chemical intolerance

    DEFF Research Database (Denmark)

    Dantoft, Thomas Meinertz; Andersson, Linus; Nordin, Steven

    2015-01-01

    Chemical intolerance (CI) is a term used to describe a condition in which the sufferer experiences a complex array of recurrent unspecific symptoms attributed to low-level chemical exposure that most people regard as unproblematic. Severe CI constitutes the distinguishing feature of multiple...

  18. Chemical modification

    Science.gov (United States)

    R. M. Rowell

    2004-01-01

    Wood is a hygroscopic resource that was designed to perform, in nature, in a wet environment. Nature is programmed to recycle wood in a timely way through biological, thermal, aqueous, photochemical, chemical, and mechanical degradations. In simple terms, nature builds wood from carbon dioxide and water and has all the tools to recycle it back to the starting chemicals...

  19. Environmental variation partitioned into separate heritable components

    DEFF Research Database (Denmark)

    Ørsted, Michael; Rohde, Palle Duun; Hoffmann, Ary A

    2018-01-01

    : plasticity across environments, variability in plasticity, variation within environments, and differences in within-environment variation across environments. We assessed these components for cold tolerance across five rearing temperatures using the Drosophila melanogaster Genetic Reference Panel (DGRP...... functionally validated the effects of a subset of candidate genes affecting each of the four components of environmental variation and also confirmed the genetic and phenotypic correlations obtained from the DGRP in distinct genetic backgrounds. We delineate selection targets associated with environmental...

  20. Affective Networks

    Directory of Open Access Journals (Sweden)

    Jodi Dean

    2010-02-01

    Full Text Available This article sets out the idea of affective networks as a constitutive feature of communicative capitalism. It explores the circulation of intensities in contemporary information and communication networks, arguing that this circulation should be theorized in terms of the psychoanalytic notion of the drive. The article includes critical engagements with theorists such as Guy Debord, Jacques Lacan, Tiziana Terranova, and Slavoj Zizek.

  1. Variations in brain DNA

    Directory of Open Access Journals (Sweden)

    Jesus eAvila

    2014-11-01

    Full Text Available It is assumed that DNA sequences are conserved in the diverse cell types present in a multicellular organism like the human being. Thus, in order to compare the sequences in the genome of DNA from different individuals, nucleic acid is commonly isolated from a single tissue. In this regard, blood cells are widely used for this purpose because of their availability. Thus blood DNA has been used to study genetic familiar diseases that affect other tissues and organs, such as the liver, heart, and brain. While this approach is valid for the identification of familial diseases in which mutations are present in parental germinal cells and, therefore, in all the cells of a given organism, it is not suitable to identify sporadic diseases in which mutations might occur in specific somatic cells. This review addresses somatic DNA variations in different tissues or cells (mainly in the brain of single individuals and discusses whether the dogma of DNA invariance between cell types is indeed correct. We will also discuss how single nucleotide somatic variations arise, focusing on the presence of specific DNA mutations in the brain.

  2. Early life stress and serotonin transporter gene variation interact to affect the transcription of the glucocorticoid and mineralocorticoid receptors, and the co-chaperone FKBP5, in the adult rat brain.

    Directory of Open Access Journals (Sweden)

    Rick H. A. Van der Doelen

    2014-10-01

    Full Text Available The short allelic variant of the serotonin transporter (5-HTT promoter-linked polymorphic region (5-HTTLPR has been associated with the etiology of major depression by interaction with early life stress (ELS. A frequently observed endophenotype in depression is the abnormal regulation of levels of stress hormones such as glucocorticoids. It is hypothesized that altered central glucocorticoid influence on stress-related behavior and memory processes could underlie the depressogenic interaction of 5-HTTLPR and ELS. One possible mechanism could be the altered expression of the genes encoding the glucocorticoid and mineralocorticoid receptor (GR, MR and their inhibitory regulator FK506-binding protein 51 (FKBP5 in stress-related forebrain areas. To test this notion, we exposed heterozygous (5-HTT+/- and homozygous (5-HTT-/- serotonin transporter knockout rats and their wildtype littermates (5-HTT+/+ to daily 3 h maternal separations from postnatal day 2 to 14. In the medial prefrontal cortex (mPFC and hippocampus of the adult male offspring, we found that GR, MR and FKBP5 mRNA levels were affected by ELS x 5-HTT genotype interaction. Specifically, 5-HTT+/+ rats exposed to ELS showed decreased GR and FKBP5 mRNA in the dorsal and ventral mPFC, respectively. In contrast, 5-HTT+/- rats showed increased MR mRNA levels in the hippocampus and 5-HTT-/- rats showed increased FKBP5 mRNA in the ventral mPFC after ELS exposure. These findings indicate that 5-HTT genotype determines the specific adaptation of GR, MR and FKBP5 expression in response to early life adversity. Therefore, altered extra-hypothalamic glucocorticoid signaling should be considered to play a role in the depressogenic interaction of ELS and 5-HTTLPR.

  3. Accommodating variation: dialects, idiolects, and speech processing.

    Science.gov (United States)

    Kraljic, Tanya; Brennan, Susan E; Samuel, Arthur G

    2008-04-01

    Listeners are faced with enormous variation in pronunciation, yet they rarely have difficulty understanding speech. Although much research has been devoted to figuring out how listeners deal with variability, virtually none (outside of sociolinguistics) has focused on the source of the variation itself. The current experiments explore whether different kinds of variation lead to different cognitive and behavioral adjustments. Specifically, we compare adjustments to the same acoustic consequence when it is due to context-independent variation (resulting from articulatory properties unique to a speaker) versus context-conditioned variation (resulting from common articulatory properties of speakers who share a dialect). The contrasting results for these two cases show that the source of a particular acoustic-phonetic variation affects how that variation is handled by the perceptual system. We also show that changes in perceptual representations do not necessarily lead to changes in production.

  4. Hazardous Chemicals

    Centers for Disease Control (CDC) Podcasts

    2007-04-10

    Chemicals are a part of our daily lives, providing many products and modern conveniences. With more than three decades of experience, The Centers for Disease Control and Prevention (CDC) has been in the forefront of efforts to protect and assess people's exposure to environmental and hazardous chemicals. This report provides information about hazardous chemicals and useful tips on how to protect you and your family from harmful exposure.  Created: 4/10/2007 by CDC National Center for Environmental Health.   Date Released: 4/13/2007.

  5. Does mood affect trading behavior?

    OpenAIRE

    Kaustia, Markku; Rantapuska, Elias

    2012-01-01

    We test whether investor mood affects trading with data on all stock market transactions in Finland, utilizing variation in daylight and local weather. We find some evidence that environmental mood variables (local weather, length of day, daylight saving and lunar phase) affect investors’ direction of trade and volume. The effect magnitudes are roughly comparable to those of classical seasonals, such as the Monday effect. The statistical significance of the mood variables is weak in many case...

  6. Chemical Peel

    Science.gov (United States)

    ... complications in chemical peeling. Journal of Cutaneous and Aesthetic Surgery. 2010;3:186. Langsdon PR, et al. ... Discovery's Edge Magazine Search Publications Training Grant Positions Education Mayo Clinic College of Medicine and Science Mayo ...

  7. Chemical carcinogens

    National Research Council Canada - National Science Library

    Searle, Charles E

    1976-01-01

    Cancer causing agents are now known to exist throughout the environment-in polluted air and tobacco smoke, in various plants and foods, and in many chemicals that are used in industry and laboratories...

  8. Chemical Carcinogenesis

    OpenAIRE

    Oliveira, Paula A.; Aura Colaço; Raquel Chaves; Henrique Guedes-Pinto; Luis F. De-La-Cruz P.; Carlos Lopes

    1980-01-01

    The use of chemical compounds benefits society in a number of ways. Pesticides, for instance, enable foodstuffs to be produced in sufficient quantities to satisfy the needs of millions of people, a condition that has led to an increase in levels of life expectancy. Yet, at times, these benefits are offset by certain disadvantages, notably the toxic side effects of the chemical compounds used. Exposure to these compounds can have varying effects, ranging from instant death to a gradual process...

  9. Chemical carcinogenesis.

    Science.gov (United States)

    Oliveira, Paula A; Colaço, Aura; Chaves, Raquel; Guedes-Pinto, Henrique; De-La-Cruz P, Luis F; Lopes, Carlos

    2007-12-01

    The use of chemical compounds benefits society in a number of ways. Pesticides, for instance, enable foodstuffs to be produced in sufficient quantities to satisfy the needs of millions of people, a condition that has led to an increase in levels of life expectancy. Yet, at times, these benefits are offset by certain disadvantages, notably the toxic side effects of the chemical compounds used. Exposure to these compounds can have varying effects, ranging from instant death to a gradual process of chemical carcinogenesis. There are three stages involved in chemical carcinogenesis. These are defined as initiation, promotion and progression. Each of these stages is characterised by morphological and biochemical modifications and result from genetic and/or epigenetic alterations. These genetic modifications include: mutations in genes that control cell proliferation, cell death and DNA repair--i.e. mutations in proto-oncogenes and tumour suppressing genes. The epigenetic factors, also considered as being non-genetic in character, can also contribute to carcinogenesis via epigenetic mechanisms which silence gene expression. The control of responses to carcinogenesis through the application of several chemical, biochemical and biological techniques facilitates the identification of those basic mechanisms involved in neoplasic development. Experimental assays with laboratory animals, epidemiological studies and quick tests enable the identification of carcinogenic compounds, the dissection of many aspects of carcinogenesis, and the establishment of effective strategies to prevent the cancer which results from exposure to chemicals.

  10. Antimicrobial price variation: Conundrum of medical profession!

    Directory of Open Access Journals (Sweden)

    Rataboli P

    2007-01-01

    Full Text Available Pharmacoeconomics plays a pivotal role in clinical practice. High medicine prices can adversely affect a patient′s finances and compliance. The Indian pharmaceutical industry has become a cornucopia of medicines with wide variation in prices for the same medicine marketed under different brand names. Price list of available antimicrobial brands was procured from a commercial drug directory. Average price of widely prescribed oral antimicrobials was found and price variation between different brands was calculated. The variation in medicine prices was found to be from 95% lower to more than 350% higher than the average price. Implications of price variation in clinical practice are discussed and remedial measures suggested.

  11. [Affective dependency].

    Science.gov (United States)

    Scantamburlo, G; Pitchot, W; Ansseau, M

    2013-01-01

    Affective dependency is characterized by emotional distress (insecure attachment) and dependency to another person with a low self-esteem and reassurance need. The paper proposes a reflection on the definition of emotional dependency and the confusion caused by various denominations. Overprotective and authoritarian parenting, cultural and socio-environmental factors may contribute to the development of dependent personality. Psychological epigenetic factors, such as early socio-emotional trauma could on neuronal circuits in prefronto-limbic regions that are essential for emotional behaviour.We also focus on the interrelations between dependent personality, domestic violence and addictions. The objective for the clinician is to propose a restoration of self-esteem and therapeutic strategies focused on autonomy.

  12. Cytoplasmic genetic variation and extensive cytonuclear interactions influence natural variation in the metabolome

    DEFF Research Database (Denmark)

    Joseph, Bindu; Corwin, Jason A.; Li, Baohua

    2013-01-01

    affects phenotypic variation. This showed that the cytoplasmic variation had effects similar to, if not larger than, the largest individual nuclear locus. Inclusion of cytoplasmic variation into the genetic model greatly increased the explained phenotypic variation. Cytoplasmic genetic variation...... was a central hub in the epistatic network controlling the plant metabolome. This epistatic influence manifested such that the cytoplasmic background could alter or hide pairwise epistasis between nuclear loci. Thus, cytoplasmic genetic variation plays a central role in controlling natural variation......Understanding genome to phenotype linkages has been greatly enabled by genomic sequencing. However, most genome analysis is typically confined to the nuclear genome. We conducted a metabolomic QTL analysis on a reciprocal RIL population structured to examine how variation in the organelle genomes...

  13. Passive sampling of perfluorinated chemicals in water: Flow rate effects on chemical uptake

    NARCIS (Netherlands)

    Kaserzon, S.L.; Vermeirssen, E.L.M.; Hawker, D.W.; Kennedy, K.; Bentley, C.; Thompson, J.; Booij, K.; Mueller, J.F.

    2013-01-01

    A recently developed modified polar organic chemical integrative sampler (POCIS) provides a means for monitoring perfluorinated chemicals (PFCs) in water. However, changes in external flow rates may alter POCIS sampling behaviour and consequently affect estimated water concentrations of analytes. In

  14. Effect of water table variations and input of natural organic matter on the cycles of C and N, and mobility of As, Zn and Cu from a soil impacted by the burning of chemical warfare agents: A mesocosm study.

    Science.gov (United States)

    Thouin, Hugues; Battaglia-Brunet, Fabienne; Gautret, Pascale; Le Forestier, Lydie; Breeze, Dominique; Séby, Fabienne; Norini, Marie-Paule; Dupraz, Sebastien

    2017-10-01

    A mesocosm study was conducted to assess the impact of water saturation episodes and of the input of bioavailable organic matter on the biogeochemical cycles of C and N, and on the behavior of metal(loid)s in a soil highly contaminated by the destruction of arsenical shells. An instrumented mesocosm was filled with contaminated soil taken from the "Place-à-Gaz" site. Four cycles of dry and wet periods of about one month were simulated for 276days. After two dry/wet cycles, organic litter sampled on the site was added above the topsoil. The nitrogen cycle was the most impacted by the wet/dry cycles, as evidenced by a denitrification microbial process in the saturated level. The concentrations of the two most mobile pollutants, Zn and As, in the soil water and in the mesocosm leachate were, respectively, in the 0.3-1.6mM and 20-110μM ranges. After 8months of experiment, about 83g·m -3 of Zn and 3.5g·m -3 of As were leached from the soil. These important quantities represent cycles had no major effect on Zn mobility. However, soil saturation induced the immobilization of As by trapping As V but enhanced As III mobility. These phenomena were amplified by the presence of bioavailable organic matter. The study showed that the natural deposition of forest organic litter allowed a part of the soil's biological function to be restored but did not immobilize all the Zn and As, and even contributed to transport of As III to the surrounding environment. The main hazard of this type of site, contaminated by organo-arsenic chemical weapons, is the constitution of a stock of As that may leach into the surrounding environment for several hundred years. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Natural variations in expression of regulatory and detoxification related genes under limiting phosphate and arsenate stress in Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Tapsi eShukla

    2015-10-01

    Full Text Available Abiotic stress including nutrient deficiency and heavy metal toxicity severely affects plant growth, development, and productivity. Genetic variations within and in between species are one of the important factors in establishing interactions and responses of plants with the environment. In the recent past, natural variations in Arabidopsis thaliana have been used to understand plant development and response towards different stresses at genetic level. Phosphorus (Pi deficiency negatively affects plant growth and metabolism and modulates expression of the genes involved in Pi homeostasis. Arsenate, As(V, a chemical analogue of Pi, is taken up by the plants via phosphate transport system. Studies suggest that during Pi deficiency, enhanced As(V uptake leads to increased toxicity in plants. Here, the natural variations in Arabidopsis have been utilized to study the As(V stress response under limiting Pi condition. The primary root length was compared to identify differential response of three Ara