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乳源酵母Pichia fermentans的抗氧化特性

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哈尔滨工业大学学报 2010年第2期42卷 292-296页

作者：陈历水马莺 jean-louis MAUBOIS 刘巧红哈尔滨工业大学食品科学与工程学院哈尔滨150090 法国农业科学研究院雷恩乳品中心雷恩法国35042

为得到新的天然抗氧化剂,采用DPPH法和抑制脂质过氧化法对11株来源于牛乳的酵母菌抗氧化活性进行测定,包括他们的完整细胞和无细胞提取物,发现Pichia fermentans BY5有较好的抗氧化活性.分析不同条件下*** BY5细胞提取物的抗氧化活性,... 详细信息

为得到新的天然抗氧化剂,采用DPPH法和抑制脂质过氧化法对11株来源于牛乳的酵母菌抗氧化活性进行测定,包括他们的完整细胞和无细胞提取物,发现Pichia fermentans BY5有较好的抗氧化活性.分析不同条件下*** BY5细胞提取物的抗氧化活性,发现培养基的起始pH值、培养时间、培养基种类对酵母菌的抗氧化活性和蛋白质含量影响显著(P<0.05);而抗氧化活性与蛋白质含量显著相关(P<0.01).将酵母BY5在pH6的麦芽培养基中培养2d后清除DPPH活性可达60%;在pH6的YPD培养基中培养4d后抑制脂质过氧化能力达到74%.

关键词： Pichia fermentans 抗氧化活性蛋白质原料乳

Sliding walls: a new paradigm for fluidic actuation and protocol implementation in microfluidics

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Microsystems & Nanoengineering 2020年第1期6卷 1093-1102页

作者： Bastien Venzac Yang Liu Ivan Ferrante Pablo Vargas Ayako Yamada Remi Courson Marine Verhulsel Laurent Malaquin jean-louis Viovy Stephanie Descroix Laboratoire Physico Chimie Curie Institut CuriePSL Research UniversityCNRS UMR16875005 ParisFrance Sorbonne Universites UPMC Univ Paris 0675005 ParisFrance Institut Pierre-Gilles de Gennes PSL Research University75005 ParisFrance Institut Curie PSL Research UniversityCNRS UMR 14475005 ParisFrance LAAS-CNRS Universitéde ToulouseCNRS31400 ToulouseFrance

Currently,fluidic control in microdevices is mainly achieved either by external pumps and valves,which are expensive and bulky,or by valves integrated in the *** types of internal valves or actuation methods have been proposed,but they generally impose difficult compromises between performance and fabrication *** propose here a new paradigm for actuation in microfluidic devices based on rigid or semi-rigid walls with transversal dimensions of hundreds of micrometres that are able to slide within a microfluidic chip and to intersect microchannels with hand-driven or translation stage-based *** this new concept for reconfigurable microfluidics,the implementation of a wide range of functionalities was facilitated and allowed for no or limited dead volume,low cost and low *** demonstrate here several fluidic operations,including on/off or switch valving,where channels are blocked or reconfigured depending on the sliding wall *** valves sustain pressures up to *** and reversible compartmentalisation of large microfluidic chambers were also *** last possibility was applied to a“4D”migration assay of dendritic cells in a collagen ***,sliding walls containing a hydrogel-based membrane were developed and used to concentrate,purify and transport biomolecules from one channel to another,such functionality involving complex fluidic transport patterns not possible in earlier microfluidic ***,this toolbox is compatible with“soft lithography”technology,allowing easy implementation within usual fabrication workflows for polydimethylsiloxane *** new technology opens the route to a variety of microfluidic applications,with a focus on simple,hand-driven devices for point-of-care or biological laboratories with low or limited equipment and resources.

关键词： walls hundreds operations

The ecology of sexual dimorphism in size and shape of the freshwater blenny Salaria fluviatilis

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Current Zoology 2018年第2期64卷 183-191页

作者： martin LAPORTE Patrick BERREBI Julien CLAUDE Dolors VINYOLES Quim Pou-RoVIRA jean-Claude RAYMOND Pierre MAGNAN lnstitut des Sciences de I'Evolution de Montpellier (ISEM) UMR 5554 UM2-CNRS-IRD Universite de Montpellier II CC065 Place E. Bataillon Montpellier Cedex 534095 France Departement de Biologie Institut de Biologie Integrative et des Systemes (IBIS) Universite Laval Quebec Quebec City Canada G1V 0A6 Department of Evolutionary Biology Ecology and Environmental Sciences Faculty of Biology University of Barcelona Avda. Diagonal 643 Barcelona 08028 Spain Sorello estudis al medi aquatic Placa St. Pere 15 Baixos 17007 Girona Spain Office National de I'Eau et des Milieux Aquatiques (0NEMA) Unite Specialisee Milieux Lacustres Pisciculture de Rives 13 Quai de Rives Thonon-les-Bains 74200 France Centre de recherche sur les interactions bassins versants-ecosystemes aquatiques (RIVE) Universite du Quebec a Trois-Rivieres C. P. 500 Trois-Rivieres Quebec City Canada G9A 5H7

Sexual selection is considered the major cause of sexual dimorphism, but recent observations suggest that natural selection may play a more important role in the evolution of sex differentiation than previously recognized. Therefore, studying the trade-offs between natural selection and sexual selection is crucial to a better understanding of the ecology underlying the evolution of sexual dimorphism. The freshwater blenny Salaria fluviatilis, a fish inhabiting lakes and rivers around the Mediterranean Sea, displays strong sexual dimorphism in size, shape, and behavior （i.e., larger body and head size for males and higher swimming requirements for females during the reproductive period）. We tested for differences in sexual dimorphism in size and shape between the populations from lake and river habitats with the goal of identifying the trade-offs between natural and sexual se- lection that underlie variations in sexual dimorphism in this species. Our results show i） differences in sexual size dimorphism （SSizeD） in accordance to Rensch＇s rule （i.e., larger individuals in rivers associated with higher SSizeD）, and ii） a decrease in shape differentiation between males and fe- males in lake populations. Together, this suggests that the different environmental conditions between lake and river habitats （e.g., resource limitations, predation pressure, water velocity） affect the relative importance of sexual selection in the display of sexual dimorphism within the species. This study highlights the importance of considering the environmental conditions to which populations are exposed to better understand the ecology underlying the evolution of sexual dimorphism.

关键词： evolutionary ecology geometric morphometrics phenotype-environment interaction Rensch's rule sexual dimorphism.

Genetics of seed flavonoid content and antioxidant activity in cowpea(Vigna unguiculata L. Walp.)

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The Crop Journal 2016年第5期4卷 391-397页

作者： Maina Antoine Nassourou Yanou Nicolas Njintang Tchiagam jean-Baptiste Noubissié Richard Marcel Nguimbou Joseph martin Bell Department of Biological Sciences Faculty of Science University of Ngaoundéré Department of Food Science and Nutrition ENSAI University of Ngaoundéré Genetics and Plant Breeding Unit Department of Plant Biology Faculty of Science University of Yaoundé I

Information about the type of gene action governing the inheritance of cowpea seed flavonoid content and antioxidant activity is prerequisite for starting an effective breeding program for developing improved varieties. For this purpose, half-diallel crosses among seven diverse parents were made. The homozygous parents and 21 F1 hybrids were evaluated at Maroua in the Sudano-Sahelian zone of Cameroon using a randomized complete block design with three replicates. Flour samples produced from decorticated seeds were used for biochemical analysis. Analysis of variance showed significant differences(P < 0.001) among genotypes for the studied traits with ranges of 363.6–453.9 mg rutin equivalent per 100 g dry weight(DW) for total flavonoids, 13.38–30.73 mg ascorbic acid equivalent per 1 g DW for ferric iron reducing activity, 70.98–266.93 mg trolox equivalent per 100 g DW for 2,2-diphenyl-1-picrylhydrazyl(DPPH) free radical scavenging activity, and 90.93–370.62 mg trolox equivalent per 100 g DW for 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS) free radical scavenging activity. Both additive and non-additive gene effects were significant in the genetic control of these traits, but dominance variance was greater than additive variance. The traits were mainly controlled by overdominance model suggesting a selection in the delayed ***- and narrow-sense heritability estimates varied from 0.90 to 0.99 and from 0.12 to 0.45,respectively. The variances due to both general and specific combining ability were highly significant for all studied traits. Recessive alleles had positive effects on DPPH and ABTS scavenging activities, whereas dominant alleles had positive effects on flavonoid content and ferric iron reducing activity. These results could help cowpea breeders to improve the antioxidant potential of cowpea seeds by appropriate selection.

关键词： Cowpea Genetic improvement Diallel analysis Antioxidant properties

The Global Boundary Stratotype Section and Point （GSSP） for the base of the Pliensbachian Stage （Lower Jurassic）, Wine Haven, Yorkshire, UK

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Episodes 2006年第2期29卷 93-106页

作者： Christian Meister martin Aberhan Joachim Blau jean-louis Dommergues Susanne Feist-Burkhardt Ernie A. Hailwood Malcom Hart Stephen P. Hesselbos Mark W. Hounslow Mark Hylton Nicol Morton Kevin Page Greg D. Price Département de Géologie et de Paléontologie 1 route de Malagnou c.p. 6434 CH-1211 Genève 6 Switzerland Museum der Naturkunde Zentralinstitut der Humboldt-Universitat zu Berlin Institut für Palaiontolgie Invalidenstr. 43 D-10115 Berlin Germany Institut für Geowissenschaften Diezstrasse 15 D-35390 Giessen Germany Centre des Sciences de la Terre de I＇Université de Bourgogne UMR CNRS 5561： Paléontologie analytique et Géologie sédimentaire 6 Boulevard Gabriel F-21100 Dijon. France Department of Palaeontology The Natural History Museum Cromwell Road London SW7 5BD UK Core Magnetics The Green Sedbergh Cumbria LA10 5JS UK Department of Geological Sciences University of Plymouth Drake Circus Plymouth Devon PL4 8AA UK Department of Earth Sciences University of Oxford Parks Road Oxford OXI 3PR UK CEMP Geography Dept. Lancaster Environment Centre Lancaster University Bailrigg Lancaster UK. LA1 4YB Le Chardon Quarrier Brugière F-07200 Vogüé France

Following votes by the Pliensbachian Working Group, the Jurassic Subcommission and the International Commission on Stratigraphy, lUGS ratified the proposed Global Boundary Stratotype Section and Point （GSSP） for the base of the Pliensbachian Stage （Lower Jurassic） at the base of bed 73b in the Wine Haven section, Robin Hood＇s Bay, Yorkshire Coast, UK. This level contains the characteristic ammonite association Bifericeras donovani Dommergues and Meister and Apoderoceras sp. Complementary data include： a） Strontium-isotope stratigraphy, based on analysis of belemnites which yield a calcite 87Sr/^86Sr ratio for the boundary level of 0. 707425 and data supporting interpretation of continuous sedimentation; b） Belemnite oxygen-isotope data indicate a significant temperature drop （-5 ℃） across the boundary at this locality; c） A Transgressive Systems Tract （TST） initiated in the Aplanaturn Subzone （uppermost Sinemurian） continues into the Lowermost Pliensbachian （Taylori Subzone）; it forms part of a transgressive facies cycle sensu Graciansky et al. （1998）; d） The Upper Sinemurian to lowermost Plensbachian at Wine Haven section has a predominantly norreal magnetic polarity, but two discrete reversed polarity magnetozones are present. The first spans much of the latest Sinemurian Aplanatum Subzone. It terminates 〈0.5m below the Sinemurian-Pliensbachian boundary and may prove a valuable chronostratigraphic marker The second extends from the latest Oxynotum Subzone probably through to the lower part of the Raricostatum Subzone.

关键词：普连斯巴奇阶侏罗纪 GSSP 全球界线层型剖面点

Urinary metabolic insights into host-gut microbial interactions in healthy and IBD children

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World Journal of Gastroenterology 2017年第20期23卷 3643-3654页

作者： Francois-Pierre martin Ming-Ming Su Guo-Xiang Xie Seu Ping Guiraud martin Kussmann jean-Philippe Godin Wei Jia Andreas Nydegger NestléInstitute of Health Sciences University of Hawaii Cancer Center Metabo-Profile Biotechnology(Shanghai)Co. Ltd. The Liggins Institute The University of Auckland NestléResearch Center Division of Pediatric Gastroenterology University of Lausanne

AIMTo identify metabolic signatures in urine samples from healthy and inflammatory bowel disease(IBD)*** applied liquid chromatography and gas chromatography coupled to targeted mass spectrometry(MS)-based metabolite profiling to identify and quantify bile acids and host-gut microbial metabolites in urine samples collected from 21 pediatric IBD patients monitored three times over one year(baseline,6 and 12 mo),and 27age-and gender-matched healthy *** metabolic profiles of IBD children differ significantly from healthy *** metabolic differences encompass central energy metabolism,amino acids,bile acids and gut microbial *** particular,levels of pyroglutamic acid,glutamic acid,glycine and cysteine,were significantly higher in IBD children in the course of the *** suggests that glutathione cannot be optimally synthesized and *** alterations of the enterohepatic circulation of bile acids in pediatric IBD patients is known,we show here that non-invasive urinary bile acid profiling can assess those altered hepatic and intestinal barrier *** present study shows how non-invasive sampling of urine followed by targeted MS-based metabonomic analysis can elucidate and monitor the metabolic status of children with different GI health/disease status.

关键词： Pediatric Metabolism Phenotype Growth Inflammatory bowel disease Crohn's disease Ulcerative colitis

Age,smoking and overweight contribute to the development of intestinal metaplasia of the cardia

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World Journal of Gastroenterology 2012年第17期18卷 2076-2083页

作者： Christian Felley Hanifa Bouzourene Marianne Bründler G VanMelle Antoine Hadengue Pierre Michetti Gian Dorta Laurent Spahr Emiliano Giostra jean louis Frossard Service of Gastroenterology University Hospital1000 LausanneSwitzerland Institute of Pathology University Hospital1000 LausanneSwitzerland Institute of Social and Preventive Medicine University of Lausanne1000 LausanneSwitzerland Service of Gastroenterology Geneva University Hospital1211 GenevaSwitzerland

AIM:To assess the role of Helicobacter pylori(***),gastroesophageal reflux disease(GERD),age,smoking and body weight on the development of intestinal metaplasia of the gastric cardia(IMC).METHODS:Two hundred and seventeen patients scheduled for esophagogastroduodenoscopy were enrolled in this *** biopsies from the esophagus,gastroesophageal junction and stomach were evaluated for inflammation,the presence of *** and intestinal *** correlation of these factors with the presence of IMC was assessed using logistic ***:IMC was observed in 42% of the *** age,smoking habit and body mass index(BMI) were found as potential contributors to *** risk of developing IMC can be predicted in theory by combining these factors according to the following formula:Risk of IMC = a + s-2B where a = 2,…6 decade of age,s = 0 for non-smokers or ex-smokers,1 for 10 cigarettes/d and B = 0 for BMI 25 kg/m2(BMI > 27 kg/m2 in females).Among potential factors associated with IMC,*** had borderline signif icance(P = 0.07),while GERD showed no signif ***:Age,smoking and BMI are potential factors associated with IMC,while *** and GERD show no significant *** can be predicted in theory by logistic regression analysis.

关键词： Endoscopy Gastroesophageal reflux disease Metaplasia Helicobacter pylori Obesity Smoking

Theoretical study of defect impact on two-dimensional MoS_2

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Journal of Semiconductors 2015年第12期36卷 18-23页

作者： Anna V.Krivosheeva Victor L.Shaposhnikov Victor E.Borisenko jean-louis Lazzari Chow Waileong Julia Gusakova Beng Kang Tay Belarusian State University of Informatics and Radioelectronics CNRS Aix-Marseille Université NOVITAS Nanoelectronics Centre of Excellence School of Electrical and Electronic Engineering Nanyang Technological University CINTRA CNRS NTUTHALES Nanyang Technological University

Our theoretical findings demonstrate for the first time a possibility of band-gap engineering of monolayer MoS2 crystals by oxygen and the presence of vacancies. Oxygen atoms are revealed to substitute sulfur ones, forming stable MoS2-xOx ternary compounds, or adsorb on top of the sulfur atoms. The substituting oxygen provides a decrease of the band gap from 1.86 to 1.64 eV and transforms the material from a direct-gap to an indirect-gap semiconductor. The surface adsorbed oxygen atoms decrease the band gap up to 0.98 eV depending on their location tending to the metallic character of the electron energy bands at a high concentration of the adsorbed atoms. Oxygen plasma processing is proposed as an effective technology for such band-gap modifications.

关键词： two-dimensional crystal molybdenum disulfide band gap vacancy oxygen

Is There an Earthquake Weather?

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Open Journal of Earthquake Research 2020年第2期9卷 69-82页

作者： Michel Parrot jean-louis Pincon LPC2E CNRSOrleansFrance University of Orleans OrleansFrance

The aim of this study is to check if there is a relationship between the seismic activity and the whistlers observed by the micro-satellite DEMETER. Whistlers are the waves emitted by lightning strokes during thunderstorm activity. They use to propagate in the Earth-ionosphere waveguide but also in the ionosphere and the magnetosphere mainly along the magnetic field lines. Due to this reason we have checked the whistler occurrence not close to earthquake epicenters but close to the magnetically conjugate point of these epicenters at the satellite altitude. The number of whistlers is given by a neural network in operation onboard the satellite. It appears that the whistler amplitude is attenuated at the satellite altitude around the magnetic equator. It is why we have removed the earthquakes occurring at low geomagnetic latitudes in the statistic. The whistler rate is normalized with a background value to take into account the seasons and the epicenter locations. A superposed epoch method is used to display the results between -15 and +5 days around the earthquake day and up to 1000 km from the conjugate point of the epicenters. It is shown that the whistler rate is higher the day before the earthquake at a distance less than 200 km. It would be unrealistic to believe in the possibility to use this study for earthquake prediction because everyday thunderstorm activity reliably masks seismic effects. But it is further evidence that there is a lithosphere-atmosphere-ionosphere coupling at the time of the seismic activity.

关键词： Data Processing Earthquake Whistler Ionosphere