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Peng's maximum principle for a stochastic control problem driven by a fractional and a standard Brownian motion

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Science China Mathematics 2014年第10期57卷 2025-2042页

作者： BUCKDAHN Rainer JING Shuai departement de Mathematiques Universite de Bretagne Occidentale School of Mathematics Shandong University School of Management Science and Engineering Central University of Finance and Economics

We study a stochastic control system involving both a standard and a fractional Brownian motion with Hurst parameter less than 1/*** apply an anticipative Girsanov transformation to transform the system into another one,driven only by the standard Brownian motion with coefficients depending on both the fractional Brownian motion and the standard Brownian *** derive a maximum principle and the associated stochastic variational inequality,which both are generalizations of the classical case.

关键词： fractional Brownian motion stochastic control system backward stochastic differential equation variational inequality maximum principle Girsanov transformation Galtchouk-Kunita-Watanabe decomposition

Health Promotion Discourse:The Voice for New Good

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外国语文研究（辑刊） 2021年第1期 1-13页

作者： Michael Rinn universite de bretagne occidentale

This article will analyze how the creative power deployed by the health promotion discourse against HIV/AIDS can be explained by its hybrid *** is both functional in its maximization of efficiency and its anticipation of reception,and normalizing in its unification of *** this regard,we understand the health promotion discourse as a major component of what Marc Angenot broadly calls“social discourse”(2009:8).This discourse governs citizens\way of living,by organizing,unifying and fixing limits on what is said,debated and discussed in a given society(Rinn&Sherlaw,2018).Our analysis will show how health promotion goes beyond the cognitive dimension of social *** authorities,by showing the image(we will call ethos)of responsibility,knowledge and performance,aim not only to impose a discursive dominance,in order to develop and legitimize the way of framing social life,as the dominant Zeitgeist,but also to provide ways of acting of each *** is this combination of cognition and action that gives the health promotion its persuasive power.

关键词： HIV/AIDS social reality ethos persuasion power

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A Comparison Theorem and Uniqueness Theorem of Backward Doubly Stochastic Differential Equations

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Acta Mathematicae Applicatae Sinica 2011年第2期27卷 223-232页

作者： Qian Lin Zhen Wu School of Mathematics Shandong University Jinan 250100 China Laboratoire de Mathematiques CNRS UMR 6205 Universite de Bretagne Occidentale 6 avenue Victor Le Gorgeu CS 93837 29238 Brest cedex 3 France

In this paper, we deal with one dimensional backward doubly stochastic differential equations （BDSdes）. We obtain a comparison theorem and a uniqueness theorem for BDSdes with continuous coefficients.

关键词： backward doubly stochastic differential equations comparison theorem backward stochastic integral uniqueness theorem

A Generalized Existence Theorem of Backward Doubly Stochastic Differential Equations

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Acta Mathematica Sinica,English Series 2010年第8期26卷 1525-1534页

作者： Qian LIN School of Mathematics Shandong University Ji'nan 250100 P. R. China and Laboratoire de Mathematiques CNRS UMR 6205 Universite de Bretagne Occidentale6avenue Victor Le Gorgeu CS 93837 29238 Brest cedex 3 France

In this paper, we deal with a class of one-dimensional backward doubly stochastic differential equations （BDSdes）. We obtain a generalized comparison theorem and a generalized existence theorem of BDSdes.

关键词： Backward doubly stochastic differential equations comparison theorem existence theorem backward stochastic integral

The effect of landscape complexity and microclimate on the thermal tolerance of a pest insect

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Insect Science 2018年第5期25卷 905-915页

作者： Lucy Alford Kevin Tougeron Jean-Sebastien Pierre Francoise Burel Joan van Baaren UMR 6553 ECOBIO Centre National de la Recherche Scientitique Universite de Rennes I Rennes Cedex France departement de Sciences Biologiques Insfitut de Recherche en Biologie Vegetale Universite de Montreal Montreal QC Canada universite Europeenne de bretagne (UEB) Rennes France

Landscape changes are known to exacerbate the impacts of climate change. As such, understanding the combined effect of climate and landscape on agroecosystems is vital if we are to maintain the fimction of agroecosystems. This study aimed to elucidate the effects of agricultural landscape complexity on the microclimate and thermal tolerance of an aphid pest to better understand how landscape and climate may interact to affect the thermal tolerance of pest species within the context of global climate change. Meteo- rological data were measured at the landscape level, and cereal aphids （Sitobion avenae, Metopolophium dirhodum and Rhopalosiphum padi） sampled, from contrasting landscapes （simple and complex） in winter 2013/2014 and spring 2014 in cereal fields of Brittany, France. Aphids were returned to the laboratory and the effect of landscape of origin on aphid cold tolerance （as determined by CTmin） was investigated. Results revealed that local landscape complexity significantly affected microclimate, with simple homogenous landscapes being on average warmer, but with greater temperature variation. Landscape complexity was shown to impact aphid cold tolerance, with aphids from complex land- scapes being more cold tolerant than those from simple landscapes in both winter and spring, but with differences among species. This study highlights that future changes to land use could have implications for the thermal tolerance and adaptability of insects. Fur- thermore, not all insect species respond in a similar way to microhabitat and microclimate, which could disrupt important predator-prey relationships and the ecosystem service they provide.

关键词： agroecosystems biological control cereal aphids climate change coldtolerance landscape ecology

Can soil microbial diversity influence plant metabolites and life history traits of a rhizophagous insect？ A demonstration in oilseed rape

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Insect Science 2017年第6期24卷 1045-1056页

作者： Tom Lachaise Morgane Ourry Lionel Lebreton Anne-Yvonne Guillerm-Erckelboudt Juliette Linglin Chrystelle Paty Valerie Chaminade Nathalie Marnet Julie Aubert denis Poinsot Anne-Marie Cortesero Christophe Mougel IGEPP Agrocampus Ouest INRA Universite de Rennes 1 Le Rheu France IGEPP Agrocampus Ouest INRA Universite de Rennes 1 Universite Bretagne-Loire Rennes France INRA UR1268 BIA-Le Rheu France INRA-AgroParisTech UMR 518 Applied Mathematics and Computer Sciences-Paris France

Interactions between plants and phytophagous insects play an important part in shaping the biochemical composition of plants. Reciprocally plant metabolites can influ- ence major life history traits in these insects and largely contribute to their fitness. Plant rhizospheric microorganisms are an important biotic factor modulating plant metabolites and adaptation to stress. While plant-insects or plant-microorganisms interactions and their consequences on the plant metabolite signature are well-documented, the impact of soil microbial communities on plant defenses against phytophagous insects remains poorly known. In this study, we used oilseed rape （Brassica napus） and the cabbage root fly （delia radicum） as biological models to tackle this question. Even though D. radicum is a belowground herbivore as a larva, its adult life history traits depend on aboveground signals. We therefore tested whether soil microbial diversity influenced emergence rate and fitness but also fly oviposition behavior, and tried to link possible effects to modifications in leaf and root metabolites. Through a removal-recolonization experiment, 3 soil microbial modalities （＂high,＂＂medium,＂＂low＂） were established and assessed through amplicon sequencing of 16S and 18S ribosomal RNA genes. The ＂medium＂ modality in the rhizosphere significantly improved insect development traits. Plant-microorganism interactions were marginally associated to modulations of root metabolites profiles, which could partly explain these results. We highlighted the potential role of plant-microbial interaction in plant defenses against delia radicum. Rhizospheric microbial communities must be taken into account when analyzing plant defenses against herbivores, being either below or aboveground.

关键词： Brassica napus delia radicum life history traits plant primary and secondary metabolites rhizophagous pest soil microbial diversity

Consequences of coinfection with protective symbionts on the host phenotype and symbiont titres in the pea aphid system

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Insect Science 2017年第5期24卷 798-808页

作者： Melanie Leclair Sarah Polin Thibaut Jousseaume Jean-Christophe Simon Akiko Sugio Stephanie Morliere Takema Fukatsu Tsutomu Tsuchida Yannick Outreman IGEPP Agrocampus Ouest INRA Universite de Rennes 1 Universite Bretagne-Loire Rennes France IGEPP Agrocampus OuestINRA Universit6 de Rennes 1 Le Rheu France Bioproduction Research Institute AIST Tsukuba Japan Graduate School of Science and Engineering University of Toyama Toyama Japan

Symbiotic associations between microbes and insects are widespread, and it is frequent that several symbionts share the same host individual. Hence, interactions can occur between these symbionts, influencing their respective abundance within the host with consequences on its phenotype. Here, we investigate the effects of multiple infections in the pea aphid, Acyrthosiphon pisurn, which is the host of an obligatory and several facultative symbionts. In particular, we study the influence of a coinfection with 2 protective symbionts： Harniltonella defensa, which confers protection against parasitoids, and Rickettsiella viridis, which provides protection against fungal pathogens and predators. The effects of Hamiltonella-Rickettsiella coinfection on the respective abundance of the symbionts, host fitness and efficacy of enemy protection were studied. Asymmetrical interactions between the 2 protective symbionts have been found： when they coinfect the same aphid individuals, the Rickettsiella infection affected Hamiltonella abundance within hosts but not the Hamiltonella-mediated protective phenotype while the Hamiltonella infection negatively influences the Rickettsiella-mediated protective phenotype but not its abundance. Harboring the 2 protective symbionts also reduced the survival and fecundity of host individuals. Overall, this work highlights the effects of multiple infections on symbiont abundances and host traits that are likely to impact the maintenance of the symbiotic associations in natural habitats.

关键词： Acyrthosiphon pisum Hamiltonella defensa host fitness multiple infections protective symbionts symbiont abundance

Asymptotic expansions in the central limit theorem for a branching Wiener process

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Science China Mathematics 2021年第12期64卷 2759-2774页

作者： Zhi-Qiang Gao Quansheng Liu Laboratory of Mathematics and Complex Systems(Ministry of Education) School of Mathematical SciencesBeijing Normal UniversityBeijing 100875China LMBA Campus de TohannicUniversite de Bretagne-SudCNRS UMR 6205Vannes F-56000France

We consider a branching Wiener process in R^(d),in which particles reproduce as a super-critical Galton-Watson process and disperse according to a Wiener *** B⊂R^(d),let Z_(n)(B) be the number of particles of generation n located in *** study of the central limit theorem and related results about the counting measure Z_(n)(·)is important because such results give good descriptions of the con guration of the branching Wiener process at time *** earlier works,the exact convergence rate in the central limit theorem and the asymptotic expansion until the third order have been ***,we establish the asymptotic expansion of any order in the central limit theorem under a moment condition of the form EX(logX)^(1+λ)<∞.

关键词： branching Wiener process asymptotic expansion central limit theorem

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Self-assembly of peptide-based nanostructures： Synthesis and biological activity

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Nano Research 2018年第5期11卷 2315-2335页

作者： Lena Guyon Elise Lepeltier Catherine Passirani Micro & Nanomedecines Translationnelles-MINT UNIV Angers INSERM U 1066 CNRS UMR 6021 UBL Universite Bretagne Loire Angers F-49933 France

Peptide-based nanostructures have received much attention in the field of drug targeting. In fact, peptides have many advantages such as simplicity of the structure, biocompatibility, and chemical diversity. Moreover, some peptides, which are called cell-penetrating peptides, can cross cellular membranes and carry small molecules, small interfering RNA, or viruses inside live cells. These molecules are often covalently or noncovalently linked to cargoes, thus forming amphiphilic conjugates that can self-assemble. Supramolecular nanostructures formed from peptides are used in nanomedicine as a carrier to protect a drug and to target cancer cells. This review explores aliphatic-chain-conjugated peptides and drug-conjugated peptides that can self-assemble. Special emphasis is placed on the synthesis procedure, nanostructure formation, and biological activity.

关键词： self-assembly cell penetrating peptide nanoparticle peptide