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喷丸处理对TiB2／Al复合材料表面基体力学性能的影响

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材料研究学报 2009年第3期23卷 237-241页

作者：栾卫志姜传海嵇宁上海交通大学材料科学与工程学院上海200240 LEMHE/ICMMO UMR 8182Universite Paris-Sud 1191405 Orsay France

通过X射线衍射线形分析表征了喷丸表面的组织结构,利用原位拉伸X射线衍射应力分析研究了TiB_2/6351Al复合材料喷丸表面基体的力学行为。结果表明,喷丸后复合材料表面基体的屈服强度提高了26%,整体强度提高约28%,显微硬度提高50%以上。... 详细信息

通过X射线衍射线形分析表征了喷丸表面的组织结构,利用原位拉伸X射线衍射应力分析研究了TiB_2/6351Al复合材料喷丸表面基体的力学行为。结果表明,喷丸后复合材料表面基体的屈服强度提高了26%,整体强度提高约28%,显微硬度提高50%以上。喷丸前、后复合材料基体承载系数分别为81%和83%,喷丸后的基体承载系数略有提高。喷丸表面基体的晶块尺寸及位错密度分别约51 nm和3.05×10^(14)m^(-2),晶块细化及位错密度增高是导致表面基体力学性能提高的主要原因。

关键词：复合材料喷丸强化基体性能 X射线衍射金属基复合材料组织结构

DIFFUSE SCATTERING AND INTRAMOLECULAR FLExiBILITY IN PROTEINS

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DIFFUSE SCATTERING AND INTRAMOLECULAR FLEXIBILITY IN PROTEIN...

An Update on Abscisic Acid Signaling in Plants and More

Sixteenth Congress of the International Union of Crystallography

作者： J-P.Benoit P.Faure J.Doucet LURE and Laboratoire de Physique des Solides Universite Paris-SudF91405 OrsayFrance

＜正＞The growing interest in the dynamical behaviour of proteins is motivated by the fact that in many cases the functional roles of these biological molecules do not only depend on their rigid three-dimensional stru...

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Molecular Plant 2008年第2期1卷 198-217页

作者： Aleksandra Wasilewsk.a Florina Vlad Caroline Sirichandra Yulia Redko Fabien Jammes Christiane Valon Nicolas Frei dit Frey Jeffrey Leung Institut des Sciences du Vegetal Centre National de la Recherche Scientifique UPR 23551 Avenue de la Terrasse Bat. 23 91190 Gif-sur-Yvette France CNRS UPR9073 Institut de Biologie Physico-Chimique 13 rue Pierre et Marie Curie 75005 Paris France Laboratoire Signalisation et Regulation Coordonnee du Metabolisme Carbone et Azote Institut de Biotechnologie des Plantes (UMR8618) Universite Paris-Sud F-91405 Orsay Cedex France

The mode of abscisic acid （ABA） action, and its relations to drought adaptive responses in particular, has been a captivating area of plant hormone research for much over a decade. The hormone triggers stomatal closure to limit water loss through transpiration, as well as mobilizes a battery of genes that presumably serve to protect the cells from the ensuing oxidative damage in prolonged stress. The signaling network orchestrating these various responses is, however, highly complex. This review summarizes several significant advances made within the last few years. The biosynthetic pathway of the hormone is now almost completely elucidated, with the latest identification of the ABA4 gene encoding a neoxanthin synthase, which seems essential for de novo ABA biosynthesis during water stress. This leads to the interesting question on how ABA is then delivered to perception sites. In this respect, regulated transport has attracted renewed focus by the unexpected finding of a shoot-to-root translocation of ABA during drought response, and at the cellular level, by the identification of a B-galactosidase that releases biologically active ABA from inactive ABA-glucose ester. Surprising candidate ABA receptors were also identified in the form of the Flowering Time Control Protein A （FCA） and the Chloroplastic Magnesium Protoporphyrin-IX Chelatase H subunit （CHLH） in chloroplast-nucleus communication, both of which have been shown to bind ABA in vitro. On the other hand, the protein（s） corresponding to the physiologically detectable cell-surface ABA receptor（s） is （are） still not known with certainty. Genetic and physiological studies based on the guard cell have reinforced the central importance of reversible phosphorylation in modulating rapid ABA responses. Sucrose Non-Fermenting Related Kinases （SnRK）, Calcium-Dependent Protein Kinases （CDPK）, Protein Phosphatases （PP） of the 2C and 2A classes figure as prominent regulators in this single-cell model. Identifying their d

关键词： Abscisic Acid Signaling Plants and More

Integrative rodent models for assessing male reproductive toxicity of environmental endocrine active substances

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Asian Journal of Andrology 2014年第1期16卷 60-70页

作者： Jacques Auger Florence Eustache Virginie Rouiller-Fabre Marie Chantal Canivenc-Lavier Gabriel Livera Service d'Histologie-Embryologie Biologie de la Reproduction/CECOS Site Port-Royal - Cochin/Broca/H6tel Dieu H6pitaux Universitaires Paris Centre Paris France Departement de Genetique et Developpement INSERM U 567 and Institut Cochin Universite Paris Descartes Paris and Service d'Histologie-Embryologie-Cytogen6tique 8iologie de la Reproduction/CECOS H6pital Jean Verdier Bondy France 1NRA/UMR 1324 CNRS/UMR6265 Centre des Sciences du GoOt et de I'Atimentation Dijon France. Laboratoire de Developpement des Gonades UMR 967 INSERM CEA DSV IRCM SCSR Universit paris Diderot Sorbonne Paris Cite Universit paris sud Fontenay-aux Roses France and

In the present review, we first summarize the main benefits, limitations and pitfalls of conventional in vivo approaches to assessing male reproductive structures and functions in rodents in cases of endocrine active substance （EAS） exposure from the postulate that they may provide data that can be extrapolated to humans. Then, we briefly present some integrated approaches in rodents we have recently developed at the organism level. We particularly focus on the possible effects and modes of action （MOA） of these substances at low doses and in mixtures, real-life conditions and at the organ level, deciphering the precise effects and MOA on the fetal testis. It can be considered that the in vivo experimental EAS exposure of rodents remains the first choice for studies and is a necessary tool （together with the epidemiological approach） for understanding the reproductive effects and MOA of EASs, provided the pitfalls and limitations of the rodent models are known and considered. We also provide some evidence that classical rodent models may be refined for studying the multiple consequences of EAS exposure, not only on the reproductive axis but also on various hormonally regulated organs and tissues, among which several are implicated in the complex process of mammalian reproduction. Such models constitute an interesting way of approaching human exposure conditions. Finally, we show that organotypic culture models are powerful complementary tools, especially when focusing on the MOA. All these approaches have contributed in a combinatorial manner to a better understanding of the impact of EAS exposure on human reproduction.

关键词： endocrine active substance endocrine disruptor exposure gonad in culture low dose mixture mouse rat rodent strain

A meta-analysis of the effects of geolocator application on birds

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Current Zoology 2013年第6期59卷 697-706页

作者： David COSTANTINI Anders Pape MOLLER Institute for Biodiversity Animal Health and Comparative Medicine Graham Kerr Building College of Medical Veterinary and Life Sciences University of Glasgow Glasgow G12 8QQ UK Department of Biology University of Antwerp Universiteitsplein 1 2610 Wilrijk Belgium Laboratoire d'Ecologie Systematique et Evolution CNRS UMR 8079 Universite Paris-Sud Batiment 362 F-91405 OrsayCedex France

An increasing trend in use of tracking devices such as geolocators is based on the assumption that the information gathered from such devices provides reliable information about the migratory behavior of free-living birds. This underlying as- sumption is rarely tested, as evidenced by the absence in many studies of controls, in particular treated controls, and so far never with a reasonable statistical power. Published studies have shown reduced survival prospects or delayed breeding in some species, suggesting that there may be reason to doubt that tracking devices provide unbiased information. Therefore, we conducted a meta-analysis of studies applying geolocators to wild birds to determine whether geolocators affected fitness components. Ge- olocators had an overall negative effect on fitness components, in particular survival, and ecological variables. Effect size was larger for aerial foragers than for other species. Moreover the leg band attachment method was more detrimental for birds than the leg-loop backpack harness. A meta-regression model of effect size showed independent negative effects of geolocators on ae- rial foragers, smaller species, species with smaller migration distances and in studies where geolocators were attached with a ring. These results suggest that geolocator studies should be interpreted with caution, but also raise questions whether it is ethically defensible to use geolocators on aerial foragers or small species without carrying out robust pilot studies.

关键词： Aerial foraging Aerodynamics Fitness cost Geolocator Migration Survival cost

Food preferences by birds using bird-feeders in winter： a large-scale experiment

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Avian Research 2018年第2期9卷 157-162页

作者： Piotr Tryjanowski Anders Pape Moiler Federico Morelli Piotr Indykiewicz Piotr Zduniak Lukasz Myczko Institute of Zoology Poznarn University of Life Sciences Wojska Polskiego 71C 60-62S Poznan Poland Ecologie Systematique Evolution Universite Paris-Sud CNRS AgroParisTech Universite Paris-Saclay 91405 Orsay Cedex France Department of Applied Geoinformatics and Spatial Planning Facult of Environmental Sciences Czech University of Life Sciences Prague Kamycka 129 16500 Prague 6 Czech Republic Department of Zoology and Landscaping University of Technology and Life Sciences Ks. A. Kordeckiego 20 85-225 Bydgoszcz Poland Department of Avian Biology and Ecology Faculty of Biology Adam Mickiewicz University in Poznah Umultowska 89 61-614 Poznan Poland

Background: Intentional winter bird feeding in gardens is one of the most common interactions between birds and humans. Because feeding may have both desired effects(provisioning of nutritious food for under-nourished birds) and undesired effects(favouritism of competitively superior species, transmission of disease), management of supplementary sites should be optimized from an ecological and conservation perspective. Therefore, the main aim of this study was to experimentally test winter food preferences of birds, with underlying potential influence of habitat(rural vs. urban) on realised food preferences ***: We conducted an experimental analysis of food preferences of wintering birds by provided bird-feeders in urban and rural environments across Poland. Data were collected twice during winter 2013–2014 across Poland, in total with 80 experimental ***: Sunflower seeds were the most preferred food supplement both in urban and rural habitats, significantly more exploited than any other food simultaneously available in feeders(animal fat, millet seed and dry fruits of rowanberry). However, no significant differences were recorded between urban and rural habitats in use of ***: The degree of use of a particular type of food at bird-feeders depended on the overall use of food in a bird-feeder—consumption of each of the four types of food was significantly positively correlated with that of the others, and it was positively correlated with the number of birds observed at the feeders.

关键词： Bird Food preferences Human-animal interactions Supplementary food Winter

Anxiety,depression and sleep problems:a second wave of COVID-19

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General Psychiatry 2020年第5期33卷 359-362页

作者： Patrick Peretti-Watel Caroline Alleaume Damien Léger François Beck Pierre Verger The COCONEL Group VTROME Aix MarseilleUniversiteIRDAP-HMSSAMarselilleFrance ORS PACA MarseilleProvence-Alpes-Cote d'AzurFrance EA 7330 VIFASOM(VigilanceFatigue Sommeil et SantePublique) Universite Paris 5 DescartesParislle-de-FranceFrance Centre du Sommeil et de 1aVigilance Consultation depathologie professionnelle Sommeil Vigilance et TravailAPHPParislle-de-FranceFrance CESP Universite Paris-SudVillejuifle-de-FranceFrance 不详

Dear Editor,During the early spring of 2020,as the COVID-19(coronavirus disease 2019)pandemic spread across the globe like a viral tsunami,many countries urgently implemented unprecedented mitigation measures to slow it down,following the example of China,where the disease first emerged at the end of *** a result,more than 3 billion unprepared people worldwide had to cope with living under stringent lockdown measures for weeks or months,depending on the *** with the deaths of hundreds of thousands of people from this disease,a frightening emotional shock has touched populations everywhere around the *** have lost their jobs,others have had their personal lives changed drastically;the elderly,for example,have sometimes been isolated from any *** our knowledge,no guidelines to prevent psychological trauma have been proposed,even for the most vulnerable ***,before this crisis began,several experts had warned about the potential impact of such measures on the populations’mental health.

关键词： measures planet hundreds

Antiretroviral therapy related adverse effects:Can sub-Saharan Africa cope with the new“test and treat”policy of the World Health Organization?

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Infectious Diseases of Poverty 2017年第1期6卷 212-216页

作者： Jobert Richie N.Nansseu Jean Joel R.Bigna Department of Public Health Faculty of Medicine and Biomedical Sciences of the University of YaoundeIPO Box 1364YaoundeCameroon Sickle Cell Disease Unit Mother and Child Centre of the Chantal Biya FoundationYaoundeCameroon Department of Epidemiology and Public Health Centre Pasteur of CameroonYaoundeCameroon Faculty of Medicine University of Paris Sud XILe Kremlin BicêtreParisFrance

Background:Recent studies have shown that early antiretroviral therapy(ART)initiation results in significant HIV transmission *** is the rationale behind the“test and treat”policy of the World Health Organization(WHO).Implementation of this policy will lead to an increased incidence of ART-related adverse effects,especially in sub-Saharan Africa(SSA).Is the region yet ready to cope with such a challenging issue?Main body:The introduction and widespread use of ART have drastically changed the natural history of HIV/AIDS,but exposure to ART leads to serious medication-related adverse effects mainly explained by mitochondrial toxicities,and the situation will get worse in the near ***,ART is associated with an increased risk of developing cardiovascular disease,lipodystrophy,prediabetes and overt diabetes,insulin resistance and hyperlactatemia/lactic *** prevalence of these disorders is already high in SSA,and the situation will be exacerbated by the implementation of the new WHO *** SSA countries are characterized by(extreme)poverty,very weak health systems,inadequate and low quality of health services,inaccessibility to existing health facilities,lack of(qualified)health personnel,lack of adequate equipment,inaccessibility and unaffordability of medicines,and heavy workload in a context of a double burden of ***,there is dearth of data on the incidence and predictive factors of ART-related adverse effects in SSA,to anticipate on strategies that should be put in place to prevent the occurrence of these conditions or properly estimate the upcoming burden and prepare an adequate response *** are required if we are to anticipate and effectively prevent this upcoming ***:While SSA would be the first region to experience the huge benefits of implementing the“test and treat”policy of the WHO,the region is not yet prepared to manage the consequential increased burden of ART-related toxic and

关键词： HIV/AIDS Test and treat 90-90-90 Antiretroviral therapy Sub-Saharan Africa

First-principles investigation on initial stage of 2H-SiC(001) surface oxidation

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Chinese Science Bulletin 2009年第9期54卷 1487-1494页

作者： WANG JunJie ZHANG LiTong ZENG QingFeng VIGNOLES L Gerard GUETTE Alain National Key Laboratory of Thermostructure Composite Materials Northwestern Polytechnical University Xi'an 710072 China Laboratory for Thermostructural Composites UMR 5801 CNRS-CEA-Snecma-Universite Bordeaux I F-33600 Pessac France

We present comprehensive first-principles calculations on the initial stages of SiC oxidation by atomic oxygen on the 2H-SiC(001) surface. In order to study the kinetics of oxygen incorporation at the 2H-SiC(001) surface, we investigated adsorption and diffusion of oxygen atoms and SiO2 nucleation. The adsorption sites, corresponding to the local minima of the potential energy surface (PES) for iso-lated adatoms, were identified through a comparative study of the adatom binding energy at different locations. We found that the Bridge (siloxane) site is preferred over other adsorption sites. There is no energy barrier at 0K for oxygen insertion into this site. The diffusion energy barriers that the adatom has to overcome when jumping between two adsorption sites were calculated. The premises of silica nucleation were investigated by calculating the modifications of the oxygen atom binding energy due to the interaction with neighboring adatoms.

关键词：第一性原理计算表面氧化碳化硅原子结合能吸附位 SiO2 局部极小二氧化硅