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Monitoring MVOC Profiles over Time from Isolates of Aspergillus flavus Using SPMe GC-MS

Journal of Agricultural Chemistry and environment 2014年第2期3卷 48-63页

作者： Dongdi Sun Alicia Wood-Jones Wenshuang Wang chris Vanlangenberg David Jones Julie Gower Patrice Simmons Richard e. Baird Todd e. Mlsna Department of Biochemistry Moleculary Biology Entomology and Plant Pathology Mississippi State University Mississippi State USA Department of Chemistry Mississippi State University Mississippi State USA Department of Mathematics and Statistics Mississippi State University Mississippi State USA Department of Sustainable Bioproducts Mississippi State University Mississippi State USA

Fungi produce a variety of microbial volatile organic compounds (MVOCs) during primary and secondary metabolism. The fungus, Aspergillus flavus, is a human, animal and plant pathogen which produces aflatoxin, one of the most carcinogenic substances known. In this study, MVOCs were analyzed using solid phase microextraction (SPMe) combined with GCMS from two genetically different A. flavus strains, an aflatoxigenic strain, NRRL 3357, and a non-aflatoxigenic strain, NRRL 21882. A PDMS/CAR SPMe fiber was used over 30 days to observe variations in MVOCs over time. The relative percentage of individual chemicals in several chemical classes (alcohols, aldehydes, esters, furans, hydrocarbons, ketones, and organic acids) was shown to change considerably during the varied fungal growth stages. This changing chemical profile reduces the likelihood of finding a single chemical that can be used consistently as a biomarker for fungal strain identification. In our study, discriminant analysis techniques were successfully conducted using all identified and quantified MVOCs enabling discrimination of the two A. flavus strains over the entire 30-day period. This study underscores the potential of using SPMe GCMS coupled with multivariate analysis for fungi strain identification.

关键词： Aspergillus flavus Discriminant Analysis Microbial Volatile Organic Compounds Multivariate Analysis Solid Phase Microextraction

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Study of disorder in pulsed laser deposited double perovskite oxides by first-principle structure prediction

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npj Computational Materials 2021年第1期7卷 826-833页

作者： edoardo Fertitta Sujit Das Debalina Banerjee Farbod ebrahimi Clément Barraud Kai Du He Tian chris J.Pickard Cedric Weber Ramamoorthy Ramesh Peter Littlewood David Dubbink Happy electron Ltd. LondonUnited Kingdom Department of Materials Science and engineering University of CaliforniaBerkeleyCAUSA Department of Physics King’s College LondonLondonUnited Kingdom Laboratoire Matériaux et Phénomènes Quantiques UMR 7162Universitéde ParisCNRSParisFrance Center of electron Microscopy School of Materials Science and EngineeringZhejiang UniversityHangzhouChina Department of Materials Science and Metallurgy CambridgeUnited Kingdom Advanced Institute for Materials Research Tohoku UniversitySendaiJapan Department of Physics James Franck InstituteUniversity of ChicagoChicagoILUSA

Double perovskite oxides,with generalized formula A_(2)BB'O_(6),attract wide interest due to their multiferroic and charge transfer *** offer a wide range of potential applications such as spintronics and electrically tunable ***,great practical limitations are encountered,since a spontaneous order of the B-site cations is notoriously hard to *** this joint experimental-theoretical work,we focused on the characterization of double perovskites La2TiFeO6 and La_(2)VCuO_(6) films grown by pulsed laser deposition and interpretation of the observed B-site disorder and partial charge transfer between the B-site ions.A random structure sampling method was used to show that several phases compete due to their corresponding configurational *** order to capture a representative picture of the most relevant competing microstates in realistic experimental conditions,this search included the potential formation of non-stoichiometric phases as well,which could also be directly related to the observed partial charge *** optimized the information encapsulated in the potential energy landscape,captured via structure sampling,by evaluating both enthalpic and entropic *** terms were employed as a metric for the competition of different *** approach,applied herein specifically to La_(2)TiFeO_(6),highlights the presence of highly entropic phases above the ground state which can explain the disorder observed frequently in the broader class of double perovskite oxides.

关键词： laser double structure

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Angiogenesis in asthma:a novel potential role for the Th2 memory T cell potentiating cytokine IL-25

Angiogenesis in asthma:a novel potential role for the Th2 me...

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中华医学会呼吸病学年会——2011（第十二次全国呼吸病学学术会议）

作者： chris J Corrigan Kings College London MRC & Asthma UK Centre in Allergic Mechanisms of AsthmaDivision of AsthmaAllergy & Lung Biology

Background:IL-25(IL-17e) is a Th2 type cytokine best described as a potentiator of Th2 memory *** of expression of its receptor,IL-25R,on airways structural cells suggest a wider role for IL-25 in remodelling. Objectives:Address the hypothesis that IL-25 stimulates local angiogenesis in the asthmatic bronchial mucosa.

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必需微量元素在家畜胚胎和胎儿发育中的作用

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国外畜牧学（猪与禽） 2004年第2期24卷 8-13页

作者：王玉霞 chris e Hostetler 美国华盛顿州立大学动物科学系和繁殖生物学中心

前言多年前,人们就清楚地确认了营养与繁殖之间的重要联系.例如,Benetts和Chpman(1937)就确认了新生羔羊的地方性共济失调是由于母羊放牧于缺铜草场上所致.这些信息以及随后的一些研究都表明,给妊娠期的母羊补铜能防止该病的发生.自那... 详细信息

前言多年前,人们就清楚地确认了营养与繁殖之间的重要联系.例如,Benetts和Chpman(1937)就确认了新生羔羊的地方性共济失调是由于母羊放牧于缺铜草场上所致.这些信息以及随后的一些研究都表明,给妊娠期的母羊补铜能防止该病的发生.自那时以来的研究都已表明,多种微量元素在支持多种动物正常繁殖方面具有重要的作用.但是,营养和繁殖在传统上是作为两个独立的学科加以研究的.早期的大部分研究主要是通过改变日粮的营养成分,然后测定其效应,如窝产仔数、初生体重及出生时的缺陷等.近年来的研究则更多地集中在营养影响胎儿发育的细胞机制方面.但是,许多这些研究都是以实验鼠为模型来进行的,所以还必须将其结果外推到家畜实际营养中去.需要进行许多受控的营养研究以确定家畜中是否也会发生见于实验鼠中的相同效应.采用新的技术和更为灵敏的检测手段,那么就可更容易地将营养和繁殖这两个学科一起进行研究.

关键词：必需微量元素家畜胚胎发育胎儿发育

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Sampling strategy for estimating human exposure pathways to consumer chemicals

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emerging Contaminants 2016年第1期2卷 26-36页

作者： eleni Papadopoulou Juan A.Padilla-Sanchez chris D.Collins Ian T.Cousins Adrian Covaci Cynthia A.de Wit Pim e.G.Leonards Stefan Voorspoels Cathrine Thomsen Stuart Harrad Line S.Haug Division of environmental Medicine Norwegian Institute of Public HealthLovisenberggata 80456 OsloNorway Soil Research Centre Department of Geography and Environmental ScienceUniversity of ReadingWhiteknightsReading RG66DWUK Department of environmental Science and Analytical Chemistry(ACeS) Stockholm UniversitySE 10691 StockholmSweden Toxicological Center University of AntwerpUniversiteitsplein 12610 WilrijkBelgium Institute for environmental Studies VU UniversityDe Boelelaan 10871081 HV AmsterdamThe Netherlands Flemish Institute for Technological Research(VITO) Boeretang 2002400 MolBelgium School of Geography Earth and Environmental SciencesUniversity of BirminghamEdgbaston B152TTUK

Human exposure to consumer chemicals has become a worldwide *** this work,a comprehensive sampling strategy is presented,to our knowledge being the first to study all relevant exposure pathways in a single cohort using multiple methods for assessment of exposure from each exposure *** selected groups of chemicals to be studied are consumer chemicals whose production and use are currently in a state of transition and are;per-and polyfluorinated alkyl substances(PFASs),traditional and“emerging”brominated flame retardants(BFRs and eBFRs),organophosphate esters(OPes)and phthalate esters(Pes).Information about human exposure to these contaminants is needed due to existing data gaps on human exposure intakes from multiple exposure pathways and relationships between internal and external *** environment,food and biological samples were collected from 61 participants and their households in the Oslo area(Norway)on two consecutive days,during winter ***,dust,hand wipes,and duplicate diet(food and drink)samples were collected as indicators of external exposure,and blood,urine,blood spots,hair,nails and saliva as indicators of internal exposure.A food diary,food frequency questionnaire(FFQ)and indoor environment questionnaire were also *** 2000 samples were collected in total and participant views on their experiences of this campaign were collected via *** 91%of our participants were positive about future participation in a similar project,some tasks were viewed as *** the food diary and collection of duplicate food/drink portions were the tasksmost frequent reported as“hard”/“very hard”.Nevertheless,a strong positive correlation between the reported total mass of food/drinks in the food record and the total weight of the food/drinks in the collection bottles was observed,being an indication of accurate performance of the participants despite the challenges of the sampling campaign.

关键词： Biomonitoring Indoor environment Consumer products Diet Dust Non-invasive samples

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Feature Patch Illumination Spaces and Karcher Compression for Face Recognition via Grassmannians

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Advances in Pure Mathematics 2012年第4期2卷 226-242页

作者： Jen-Mei Chang chris Peterson Michael Kirby Department of Mathematics Colorado State University Fort Collins USA Departmentof Mathematics and Statistics California State University Long Beach USA

Recent work has established that digital images of a human face, when collected with a fixed pose but under a variety of illumination conditions, possess discriminatory information that can be used in classification. In this paper we perform classification on Grassmannians to demonstrate that sufficient discriminatory information persists in feature patch (e.g., nose or eye patch) illumination spaces. We further employ the use of Karcher mean on the Grassmannians to demonstrate that this compressed representation can accelerate computations with relatively minor sacrifice on performance. The combination of these two ideas introduces a novel perspective in performing face recognition.

关键词： Grassmannians Karcher Mean Face Recognition Illumination Spaces Compressions Feature Patches Principal Angles

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TOM9.2 Is a Calmodulin-Binding Protein Critical for TOM Complex Assembly but Not for Mitochondrial Protein Import in Arabidopsis thaliana

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Molecular Plant 2017年第4期10卷 575-589页

作者： Nargis Parvin chris Carrie Isabelle Pabst Antonia Laber Debabrata Laha Melanie V. Paul Peter Geigenberger Ralf Heermann Kirsten Jung Ute C. Vothknecht Fatima Chigri Department Biology I Botany Ludwig-Maximilians-University Munich GroBhaderner Stra6e 2-4 82152 Martinsried Germany Department Biology 1 Microbiology Ludwig-Maximilians-University Munich Grobhaderner Strabe 2-4 82152 Martinsried Germany Department of Biology Center for Integrated Protein Science (Munich) Ludwig-Maximilians-University Munich 81377 Munich Germany Center for Plant Molecular Biology Plant Physiology University of Tuebingen Auf der Morgenstelle 32 72076 Tuebingen Germany present address: Plant Cell Biology IZMB University of Bonn Kirschallee 153115 Bonn Germany Present address: Center for Plant Molecular Biology Developmental Genetics University of Tubingen Auf der Morgenstelle 32 72076 Tubingen Germany

The translocon on the outer membrane of mitochondria （TOM） facilitates the import of nuclear-encoded proteins. The principal machinery of mitochondrial protein transport seems conserved in eukaryotes; however, divergence in the composition and structure of TOM components has been observed between mammals, yeast, and plants. TOM9, the plant homolog of yeast Tom22, is significantly smaller due to a truncation in the cytosolic receptor domain, and its precise function is not understood. Here we provide evidence showing that TOM9.2 from Arabidopsis thaliana is involved in the formation of mature TOM com- plex, most likely by influencing the assembly of the pore-forming subunit TOM40. Dexamethasone- induced RNAi gene silencing of TOM9.2 results in a severe reduction in the mature TOM complex, and the assembly of newly imported TOM40 into the complex is impaired. Nevertheless, mutant plants are fully viable and no obvious downstream effects of the loss of TOM complex, i.e., on mitochondrial import ca- pacity, were observed. Furthermore, we found that TOM9.2 can bind calmodulin （CAM） in vitro and that CaM impairs the assembly of TOM complex in the isolated wild-type mitochondria, suggesting a regula- tory role of TOM9.2 and a possible integration of TOM assembly into the cellular calcium signaling network.

关键词： protein import plant mitochondria TOM complex calmodulin calcium signaling

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Developmental staging of male murine embryonic gonad by SAGe analysis

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Journal of Genetics and Genomics 2009年第4期36卷 215-227页

作者： Tin-Lap Lee Yunmin Li Diana Alba Queenie R Vong Shao-Ming Wu Vanessa Baxendale Owen M. Rennert Yun-Fai chris Lau Wai-Yee Chan Section on Developmental Genomics Laboratory of Clinical Genomics Eunice Kennedy Shriver National Institute of Child Health and Human Development National Institutes of Health Bethesda MD 20892 USA Department of Medicine VA Medical Center University of California San Francisco CA 94121 USA Department of Pediatrics Biochemistry Molecular & Cellular Biology Georgetown University Washington DC 20007 USA

Despite the identification of key genes such as Sry integral to embryonic gonadal development, the genomic classification and identification of chromosomal activation of this process is still poorly understood. To better understand the genetic regulation of gonadal development, we performed Serial Analysis of Gene expression （SAGe） to profile the genes and novel transcripts, and an average of 152,000 tags from male embryonic gonads at e10.5 （embryonic day 10.5）, e11.5, e12.5, e13.5, e15.5 and e17.5 were analyzed. A total of 275,583 non-singleton tags that do not map to any annotated sequence were identified in the six gonad libraries, and 47,255 tags were mapped to 24,975 annotated sequences, among which 987 sequences were uncharacterized. Utilizing an unsupervised pattern identification technique, we established molecular staging of male gonadal development. Rather than providing a static descriptive analysis, we developed algorithms to cluster the SAGe data and assign SAGe tags to a corresponding chromosomal position; these data are displayed in chromosome graphic format. A prominent increase in global genomic activity from e10.5 to e17.5 was observed. Important chromosomal regions related to the developmental processes were identified and validated based on established mouse models with developmental disorders. These regions may represent markers for early diagnosis for disorders of male gonad development as well as potential treatment targets.

关键词： SAGe transcriptome male gonads gene tag novel transcripts cluster analysis chromosome transcription hotspot

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Assessment of the effects of Supplemental Rumen Protected B Vitamins and Choline for Periparturient Cows: A Meta-Analysis of 28 Feeding Studies

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Open Journal of Animal Sciences 2023年第1期13卷 151-165页

作者： essi evans emilie Fontaine Ousama AlZahal chris Gwyn e + e Technical Advisory Services Bowmanville Canada Jefo Nutrition Inc. Saint-Hyacinthe Canada AlZahal Innovation and Nutrition Kitchener Canada

There are currently no prescribed requirements for B vitamins or choline for dairy cows during the transition period, but many recent studies have shown a variety of benefits from supplying these nutrients to periparturient cows. The purpose of this research effort was to determine the potential benefit of including a rumen protected blend composed of B vitamins (riboflavin, folic acid, vitamin B12) and choline (RPBlend, Jefo Nutrition Inc., St. Hyacinthe, QC, Canada) for dairy cows during the transition period, based on results from 28 on-farm feeding studies (USA-12, Mexico-7, Canada-4, Chile-3, Australia-1, Brazil-1) conducted between 2011 and 2018. All farms participated in monthly herd management record keeping systems and were selected to participate in studies due to their excellent management. Meta-analyses in which risk differences were determined were used to assess the effects of the supplemental RPBlend on health parameters and reproduction. The effect size was used as the determinant of the possible contribution of RPblend on the yields of milk, energy corrected milk (eCM), fat and protein yields during the first four weeks of lactation. Results showed that the inclusion of RPblend reduced (P e first 30 days after calving. There was a tendency (P educed retained placenta and metritis. The meta-analyses revealed that the risk of the displaced abomasum and milk fever did not diminish (P > 0.10) with the inclusion of the BPBlend. The incidence rate of subclinical ketosis, determined as blood beta hydroxy butyric acid greater than 1.2 mM was lower (P (than those not supplemented. The proportion of cows confirmed pregnant by 100 days in milk was greater for cows given the BPBlend (P eld and eCM were greater for cows receiving the RPBlend (1.13 and 0.93 kg/cow respectively, P ere was no change in fat yield (P > 0.10) while the yield of milk protein was greater (P

关键词： Lactating Dairy Cows Transition Period Rumen Protection B Vitamins Choline

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A robust new metric of phenotypic distance to estimate and compare multiple trait differences among populations

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Current Zoology 2012年第3期58卷 426-439页

作者： Rebecca SAFRAN Samuel FLAXMAN Michael KOPP Darren e. IRWIN Derek BRIGGS Matthew R. eVANS W. chris FUNK David A. GRAY eileen A. HeBeTS Nathalie SeDDON elizabeth SCORDATO Laurel B. SYMeS Joseph A. TOBIAS David P. L. TOeWS J. Albert C. UY Department of ecology and evolutionary Biology University of Colorado Boulder CO 80309 U.S.A. Mathematics and B iosciences Group Faculty of Mathematics University of Vienna A-1090 Vienna Austria Current address evolutionary Biology and Modeling Group Faculty of Sciences Aix-Marseille University 13331 Marseille France. Department of Zoology University of British Columbia 6270 University Boulevard Vancouver BC Canada V6T 1Z4. Research ＆ evaluation Methodology School of Education University of Colorado Boulder CO 80309 U.S.A. School of Biological and Chemical Sciences Queen Mary University of London London E1 4NS Department of Biology Colorado State University Fort Collins CO 80523 U.S.A. Department of Biology California State University Northridge CA 91330 U.S.A. School of Biological Sciences University of Nebraska Lincoln NE 68588 U.S.A. edward Grey Institute Department of Zoology University of Oxford Oxford OX1 3PS UK Committee on evolutionary Biology The University of Chicago Chicago IL 60637U.S.A. Department of Biology Dartmouth College Hanover NH 03755 U.S.A. Department of Biology University of Miami Coral Gables FL 33146 U.S.A.

Whereas a rich literature exists for estimating population genetic divergence, metrics of phenotypic trait divergence are lacking, particularly for comparing multiple traits among three or more populations. Here, we review and analyze via simula- tion Hedges＇ g, a widely used parametric estimate of effect size. Our analyses indicate that g is sensitive to a combination of unequal trait variances and unequal sample sizes among populations and to changes in the scale of measurement. We then go on to derive and explain a new, non-parametric distance measure, ＇Aft＇, which is caiculated based upon a joint cumulative distribution function （CDF） from all populations under study. More precisely, distances are measured in terms of the percentiles in this CDF at which each population＇s median lies. Ap combines many desirable features of other distance metrics into a single metric; namely, compared to other metrics, p is relatively insensitive to unequal variances and sample sizes among the populations sam- pied. Furthermore, a key feature of Ap--and our main motivation for developing it--is that it easily accommodates simultaneous comparisons of any number of traits across any number of populations. To exemplify its utility, we employ Ap to address a ques- tion related to the role of sexual selection in speciation： are sexual signals more divergent than ecological traits in closely related taxa？ Using traits of known function in closely related populations, we show that traits predictive of reproductive performance are indeed, more divergent and more sexually dimorphic than traits related to ecological adaptation [Current Zoology 58 （3）： 426-439 2012].

关键词： effect size Phenotype divergence Sexual dimorphism Sexual selection Speciation

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