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Petrography of alluvial sands as a past and present environmental indicator:Case of the Loire River(France)

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International Journal of Sediment Research 2013年第3期28卷 285-303页

作者： Jean-Jacques MACAIRE Isabelle GAY-OVEJERO Michel BACCHI Constantin COCIRTA Luc PATRYL Stéphane RODRIGUES university Franqois-rabelais of Tours university francois-rabelais of Tours SARL RIVE 4. Commissariat a l'Energie Atomique-CEA DAMDIF

Four sample sets of the Upper and Middle Loire river sands were analyzed in order to study the impact of natural and anthropogenic factors on their petrographic composition in space(on an 800 km stretch) and *** was determined by modal analysis of three sand-size fractions using a polarizing optical microscope and calculated for each sample("standard sand" = Sst).The watershed is composed mainly of endogenic(Massif Central) and sedimentary(southern Parisian Basin) rocks.B-set sands collected in channels for different water flows in 1996 show that Sst compositions vary by only 5%.Present-day sands in the Upper Loire and Middle Loire have very high petrographic immaturity comparing to others worldwide fluvial sands,although bio-climatic conditions favor sand maturation by source-rock weathering in the *** shows the strong impact of the Massif Central on sediment yield due to relief rejuvenation as a consequence of the formation of the Alps during the *** sands stored during the Weichselian and the Holocene in the Middle Loire floodplain,although partly weathered since their deposition,show higher inputs from the endogenic rocks of the Massif Central than present-day *** can be explained by Weichselian periglacial conditions and the development of crop farming since the Neolithic,which favored mechanical erosion,particularly in the Massif Central which is characterized by a cold,humid climate and steep *** upstream-downstream change in the composition of presently deposited sand is low in the diked *** shows however that basalt and some heavy mineral grains are vulnerable to abrasion during transport and indicates a marked sediment yield from ancient sediment stored in the *** is in line with the high incision of the river bed over the last 150 years partly due to dam construction and aggregate mining.

关键词： Fluvial sand Sand petrography Sediment source Tectonics impact Human impact Loire river

Do males choose their mates in the lekking moth Achroia grisella？ Influence of female body mass and male reproductive status on male mate choice

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Insect Science 2018年第5期25卷 861-868页

作者： Marlene Goubault Rebecca Burlaud Institut de Recherche sur la Biologie de I'Insecte UMR 7261 CNRS-Universite Francois-Rabelais Tours France

Lekking males aggregate to attract females and contribute solely to egg fer- tilization, without any further parental care. Evolutionary theory therefore predicts them to be nonchoosy toward their mates, because any lost mating opportunities would out- weigh the benefits associated with such preferences. Nevertheless, due to time costs, the production of energetically costly sexual displays, and potential sperm limitation, the mat- ing effort of lekking males is often considerable. These factors, combined with the fact that many females of varying quality are likely to visit leks, could favor the evolution of male mate preferences. Here, we show that males of the lekking lesser wax moth, Achroia grisella, were indeed more likely to mate with heavier females in choice experiments, even at their virgin mating （i.e., when their reproductive resources have not yet been depleted by previous matings）. This differential female mating success could not be attributed to female behavior as heavy and light females showed similar motivation to mate （i.e., la- tency to approach the males） and time to copulate. Males seem to benefit from mating with heavier females, as fecundity positively correlated with female mass. This new em- pirical evidence shows that male mate choice may have been tmderestimated in lekking species

关键词： fecundity lek lesser wax moth mate choice mating status sexual behavior

Acromyrmex ameliae sp. n. （Hymenoptera： Formicidae）： A new social parasite of leaf-cutting ants in Brazil

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Insect Science 2007年第3期14卷 251-257页

作者： DANIVAL JOSE DE SOUZA ILKA MARIA FERNANDES SOARES TEREZINHA MARIA CASTRO DELLA LUCIA Institut de Recherche sur la Biologie de 1'Insecte Université Francois Rabelais Tours France Departamento de Biologia Animal Laboratório de Ecologia de Comunidades Departamento de Biologia Geral Universidade Federal de Vicosa MG 36570-000 Brazil

The fungus-growing ants （Tribe Attini） are a New World group of〉 200 species, all obligate symbionts with a fungus they use for food. Four attine taxa are known to be social parasites of other attines. Acromyrmex （ Pseudoatta） argentina argentina and Acromyrmex （Pseudoatta） argentina platensis （parasites of Acromyrmex lundi）, and Acromyrmex sp. （a parasite of Acromyrmex rugosus） produce no worker caste. In contrast, the recently discovered Acromyrmex insinuator （a parasite of Acromyrmex echinatior） does produce workers. Here, we describe a new species, Acromyrmex ameliae, a social parasite of Acromyrmex subterraneus subterraneus and Acromyrmex subterraneus brunneus in Minas Gerais, Brasil. Like A. insinuator, it produces workers and appears to be closely related to its hosts. Similar social parasites may be fairly common in the fungus-growing ants, but overlooked due to the close resemblance between parasite and host workers.

关键词： Acromyrmex leaf-cutting ants social evolution social parasitism

Genetic diversity of the hepatitis C virus: Impact and issues inthe antiviral therapy

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World Journal of Gastroenterology 2007年第17期13卷 2416-2426页

作者： H Le Guillou-Guillemette S Vallet C Gaudy-Graffin C Payan A Pivert A Goudeau F Lunel-Fabiani Laboratory of Virology University Hospital of Angers France and Laboratory HIFI UPRES EA 3859 University of Angers France Department of Microbiology EA 3882 CHU Morvan University Hospital of Brest France université francois rabelais INSERM ERI 19 et CHRU de Tours Tours France

The hepatitis C Virus (HCV) presents a high degree of genetic variability which is explained by the combination of a lack of proof reading by the RNA dependant RNA polymerase and a high level of viral replication. The re- sulting genetic polymorphism defines a classification in clades, genotypes, subtypes, isolates and quasispecies. This diversity is known to reflect the range of responses to Interferon therapy. The genotype is one of the pre- dictive parameters currently used to define the antiviral treatment strategy and the chance of therapeutic suc- cess. Studies have also reported the potential impact of the viral genetic polymorphism in the outcome of antivi- ral therapy in patients infected by the same HCV geno- type. Both structural and non structural genomic regions of HCV have been suggested to be involved in the Inter- feron pathway and the resistance to antiviral therapy. In this review, we first detail the viral basis of HCV diversity. Then, the HCV genetic regions that may be implicated in resistance to therapy are described, with a focus on the structural region encoded by the E2 gene and the non- structural genes NS3, NS5A and NS5B. Both mechanisms of the Interferon resistance and of the new antiviral drugs are described in this review.

关键词： Hepatitis C virus Genetic diversity Therapyresistance E2 NS3 NSSA NSSB

Delayed sexual maturity in males of Vespa velutina

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Insect Science 2018年第4期25卷 679-689页

作者： Juliette Poidatz Christophe Bressac Olivier Bonnard Denis Thiery INRA UMR1065 Santé et Agroecologie du Vignoble ISVV Bordeaux Sciences Agro Villenave d'Omon France IRBI Universite Francois Rabelais UMR CNRS 7261 Tours France

Vespa velutina var nigrithorax （Lepelletier, 1835） is an invasive predator of bees accidentally introduced in France in 2004, and it is having a serious impact on apiculture and ecosystems. Studying the reproduction of an invasive species is key to assess its population dynamic. This study explores the sexual maturation of IT. velutina males and the evolution of their fertility. The main studied parameters were physiologic （spermiogenesis, spermatogenesis） and anatomic （testes size and structure, head width）. Two populations of males were described based on their emergence period： early males in early summer or classic males in autumn. Each testis has an average of 108 testicular follicles. Spermatogenesis is synchronous, with only 1 sperm production wave, and completed, on average, at 10.3 d after emergence with the degeneration of the testes. The sperm counts in seminal vesicles of mature males are 3 x 106 in October/November and 0.8 ~ 106 in June. In com- parison, females store 0.1 x 106 sperm in their spermathecae. The early males emerged from colonies made by fertilized queens. The reproductive potential of these early males seemed limited, and their fimction in the colony is discussed. The sperm stock evolution in autumn males suggests the occurrence of a reproductive pattern of male competition for the access to females and a single copulation per male. The synchronicity of male and foundress emergences and sexual maturation is of primary importance for the mating success and the future colony development.

关键词： male fertility seminal vesicles spermiogenesis sperm stock testis Vespidae yellow-legged hornet

Insertion Of E7 Into External Loops Of Hpv-16 L1 Vlps For The Production Of Chimeric Vaccines

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Insertion Of E7 Into External Loops Of Hpv-16 L1 Vlps For Th...

Towards a simple acoustic method to evaluate the nonlinear parameter B/A of fluids

24th International Papillomavirus Conference and Clinical Workshop

作者： Eva Alvarez Latifa Bousarghin Antoine Touze Pierre Coursaget Inserm U618 Francois Rabelais UniversityToursFrance Inserm U618 Francois Rabelais UniversityToursFrance Inserm U618 Francois Rabelais UniversityToursFrance Inserm U618 Francois Rabelais UniversityToursFrance

＜正＞The aims of this study were to insert E7 and E7 peptides into the surface loops of the HPV-16 L1 protein,in order to create new chimeric HPV *** generated 7 mutants by insertion of 5 different HPV-16 E7 sequences within BC,DE,EF,and HI loops With the exception of two L1/E7 mutants containing the entire E7 sequence,all these L1 mutants were able to self- assemble into ***,the insertion of heterologous sequences was accompanied by a reduction in the yield of VLP

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Towards a simple acoustic method to evaluate the nonlinear p...

Emotions and performance in rugby

2008 IEEE International Ultrasonics Symposium

作者： francois Vander Meulen Lionel Haumesser université francois rabelais de Tours INSERM U930/CNRS FRE 2448Blois

＜正＞Background,Motivation and Objective The nonlinearity parameter is known to be an indicator of great interest in the medical field and for non destructive evaluation in industrial *** and industrial constraints o...

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Journal of Sport and Health Science 2019年第6期8卷 595-600页

作者： Mickael Campo Stéphane Champely Andrew MLane Elisabeth Rosnet Claude Ferrand Benoit Louvet SPMS(EA 4180) UBFCDijon 21078France Laboratory for Vulnerabilities and Innovation in Sport(L-VIS EA 7428)University of Lyon 1Villeurbanne 69622France Institute of Sport Faculty of EducationHealth and Well-beingUniversity of WolverhamptonWs13BDUK Faculty of Sport Sciences Universitéde Reims Champagne-ArdenneReims 51096France Research Team of Psychology of Ages of Life(EA 2114) University Francois RabelaisTours 37041France CETAPS(EA 3832) Normandie UniversitéMont Saint Aignan 76821France

Purpose:This study investigated emotion-performance relationships in rugby *** identified which emotions rugby players experienced and the extent to which these emotions were associated with performance,considering how emotions unfold over the course of a game,and whether the game was played at home or ***:Data were gathered from 22 professional male rugby union players using auto-confrontation interviews to help identify situations within games when players experienced intense *** assessed the intensity of emotions experienced before each discrete performance and therefore could assess the emotion-performance relationship within a ***:Players identified experiencing intense emotions at 189 *** in rugby union rated the quality of each performance at these 189 time-points on a visual analog scale.A Linear Mixed Effects model to investigate emotion-performance relationships found additive effects of game location,game time,and emotions on individual ***:Results showed 7 different pre-performance emotions,with high anxiety and anger associating with poor *** research should continue to investigate emotion-performance relationships during performance using video-assisted recall and use a measure of performance that has face validity for players and coaches alike.

关键词： Emotion Game location Game time Linear Mixed Effects model Multilevel analysis Performance assessment Team sport

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Ba substitution for enhancement of the thermoelectric properties of LaCoO_(3) ceramics(0≤x≤0.75)

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Journal of Advanced Ceramics 2019年第4期8卷 519-526页

作者： Mohamed Ali BOUSNINA Fabien GIOVANNELLI Loic PERRIERE Guillaume GUEGAN Fabian DELORME université francois rabelais de Tours CNRSINSA CVLGREMAN UMR7347IUT de Blois15 rue de la chocolaterieCS2903F-41029 Blois CedexFrance universitéParis 13 Sorbonne Paris CiteLaboratoire des Sciences des Procédés et des MatériauxCNRSUPR 340799 avenue J.B.ClémentF-93430 VilletaneuseFrance Institut de Chimie et des Matériaux Paris-Est UMR 7182 CNRS-UPEC2-8 Rue Henri Dunant94320 ThiaisFrance ST Microelectronics 16 Rue Pierre et Marie CurieTours 37100France

In the present work, dense perovskite ceramics were successfully prepared from a series of La1-xBaxCoO3 solid solutions in the range of substitution 0 ≤ x ≤ 0.75 using solid state reaction and conventional sintering. Structural properties of La1-xBaxCoO3 were systematically investigated and thermoelectric properties were measured in the temperature range of 330–1000 K. The results show that the thermoelectric properties of Ba-substituted LaCoO3 depend on x. Indeed, at 330 K, electrical conductivity presents an optimum value for x = 0.25 with a value of σmax ≈ 2.2×105 S·m–1 whereas the Seebeck coefficient decreases when x and/or the temperature increases. The Ba-substituted LaCoO3 samples exhibit p-type semiconducting behaviour. The best power factor value found is 3.4×10–4 W·m–1·K–2 at 330 K for x = 0.075, which is 10% higher than the optimum value measured in La1–xSrxCoO3 for x = 0.05. The thermal diffusivity and thermal conductivity increase with increasing temperature and Ba concentration. La1-xBaxCoO3 shows a maximum figure of merit(ZT = 0.048) for x = 0.05 at 330 K, 25% higher than the best value in La1–xSrxCoO3 compounds.

关键词： perovskite Ba-substituted LaCoO_(3) oxide thermoelectric p-type semiconductor

维普期刊数据库