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Analysis of a System Describing Proliferative-Quiescent Cell Dynamics

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Chinese Annals of Mathematics,Series B 2018年第2期39卷 345-356页

作者： Jean CLAIRAMBAULT benoit perthame Andrada Quillas MARAN Dedicated to Philippe G. Ciarlet on the occasion of his 80th birthda

Systems describing the dynamics of proliferative and quiescent cells are commonly used as computational models, for instance for tumor growth and *** on the very earliest stages of hematopoiesis, stem cells and early progenitors, the authors introduce a new method, based on an energy/Lyapunov functional to analyze the long time behavior of solutions. Compared to existing works, the method in this paper has the advantage that it can be extended to more complex situations. The authors treat a system with space variable and diffusion, and then adapt the energy functional to models with three equations.

关键词： Stability analysis Lyapunov functional Energy method Parabolic sys-tems Proliferative and quiescent cells Tumor growth Hematopoiesis

Dirac Concentrations in a Chemostat Model of Adaptive Evolution(In honor of the immense scientific influence of Ham Brezis)

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Chinese Annals of Mathematics,Series B 2017年第2期38卷 513-538页

作者： Alexander LORZ benoit perthame Cécile TAING Sorbonne Universits UPMC Univ Paris 06InriaLaboratoire Jacques-Louis Lions UM R CNRS 7598F75005 ParisFrance

This paper deals with a non-local parabolic equation of Lotka-Volterra type that describes the evolution of phenotypically structured populations. Nonlinearities appear in these systems to model interactions and competition phenomena leading to selection. In this paper, the equation on the structured population is coupled with a differential equation on the nutrient concentration that changes as the total population *** methods aimed at showing the convergence of the solutions to a moving Dirac mass are reviewed. Using either weak or strong regularity assumptions, the authors study the concentration of the solution. To this end, BV estimates in time on appropriate quantities are stated, and a constrained Hamilton-Jacobi equation to identify where the solutions concentrates as Dirac masses is derived.

关键词： Adaptive evolution, Asymptotic behaviour, Chemostat, Dirac concentrations,Hamilton-Jacobi equations, Lotka-Volterra equations, Viscosity solutions

Composite Waves for a Cell Population System Modeling Tumor Growth and Invasion

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Chinese Annals of Mathematics,Series B 2013年第2期34卷 295-318页

作者： Min TANG Nicolas VAUCHELET Ibrahim CHEDDAD Irene VIGNON-CLEMENTEL Dirk DRASDO benoit perthame Department of mathematics Institute of Natural Sciences and MOE-LSCShanghai Jiao Tong University INRIA Paris Rocquencourt ParisFrance Laboratoire Jacques-Louis Lions UPMC Univ Paris 06 and CNRS UMR 7598F-75005ParisFrance

In the recent biomechanical theory of cancer growth,solid tumors are considered as liquid-like materials comprising elastic *** this fluid mechanical view,the expansion ability of a solid tumor into a host tissue is mainly driven by either the cell diffusion constant or the cell division rate,with the latter depending on the local cell density(contact inhibition) or/and on the mechanical stress in the *** the two by two degenerate parabolic/elliptic reaction-diffusion system that results from this modeling,the authors prove that there are always traveling waves above a minimal speed,and analyse their *** appear to be complex with composite shapes and *** small parameters allow for analytical solutions,and in particular,the incompressible cells limit is very singular and related to the Hele-Shaw *** singular traveling waves are recovered numerically.

关键词： Traveling waves Reaction-diffusion Tumor growth Elastic material

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什么是退化抛物-双曲型方程的动理学解？

数学译林 2012年第4期31卷 343-345,342页

作者：陈贵强 benoit perthame 甘在会(译) 陆柱家(校)

非线性退化抛物一双曲型方程是最重要的几类非线性偏微分方程之一．非线性与退化性是这些方程的两个主要特征，它们产生了一些异乎寻常的现象，这些现象需要用新的数学思想、方法和理论来加以解释．另一方面，由于这类方程在实际应用中... 详细信息

非线性退化抛物一双曲型方程是最重要的几类非线性偏微分方程之一．非线性与退化性是这些方程的两个主要特征，它们产生了一些异乎寻常的现象，这些现象需要用新的数学思想、方法和理论来加以解释．另一方面，由于这类方程在实际应用中的重要性，已有了有关计算此类方程的解的各种数值方法的设计与分析的大量文献．此外，此类方程解的适定性理论（存在性、唯一性和稳定性）的研究更迫在眉睫．

关键词：双曲型方程退化性抛物非线性偏微分方程动理学线性退化数学思想数值方法

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关于肿瘤增长和治疗的一些数学知识

数学译林 2014年第4期33卷 293-293页

作者： benoit perthame 黄际政孙宇阳法国皮埃尔和玛丽居里大学不详

用偏微分方程或者自由边值问题描述肿瘤增长的数学模型现在是预测一些癌症演化的重要工具，例如基于图像分析的模型．这些模型不仅可以在医疗上预测癌症的演化，还可以用来帮助理解组织生长过程中生物的和机械的效果，以及给出最优的治... 详细信息

用偏微分方程或者自由边值问题描述肿瘤增长的数学模型现在是预测一些癌症演化的重要工具，例如基于图像分析的模型．这些模型不仅可以在医疗上预测癌症的演化，还可以用来帮助理解组织生长过程中生物的和机械的效果，以及给出最优的治疗方案，甚至在某些情况下预测失败的治疗方案．

关键词：治疗方案数学知识肿瘤数学模型自由边值问题偏微分方程图像分析生长过程

Event analysis in social multimedia： a survey

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Frontiers of Computer Science 2016年第3期10卷 433-446页

作者： Xueliang LIU Meng WANG benoit HUET School of Computer and Information Hefei University of Technology Hefei 230009 China Department of Multimedia EURECOM sophia-antipolis Nice 06560 France

Recent years have witnessed the rapid growth of social multimedia data available over the Internet. The age of huge amount of media collection provides users facihties to share and access data, while it also demands the revolution of data management techniques, since the exponential growth of social multimedia requires more scalable, effective and ro- bust technologies to manage and index them. The event is one of the most important cues to recall people＇s past memory. The reminder value of an event makes it extremely helpful in organizing data. The study of event based analysis on so- cial multimedia data has drawn intensive attention in research community. In this article, we provide a comprehensive sur- vey on event based analysis over social multimedia data, in- cluding event enrichment, detection, and categorization. We introduce each paradigm and summarize related research ef- forts. In addition, we also suggest the emerging trends in this research area.

关键词： event enrichment event detection event categorization

Formation building and collision avoidance for a fleet of NAOs based on optical sensor with local positions and minimum communication

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Science China(Information Sciences) 2019年第5期62卷 214-236页

作者： Xiaomin WANG Lorenzo BENOZZI benoit ZERR Zexiao XIE Hélène THOMAS benoit CLEMENT Engineering college Ocean University of China

Multi-robot system has become a research hotspot because of low demand on the sensors’ accuracy, high reliability, and high efficiency. To put all the robots together, formation control is a crucial problem. In this paper, we propose a local position-based method to plan trajectories and build a pyramid pattern for a fleet of NAOs in the obstacle-free environment by refering to the position-based method and giving an O(n log n) collision avoidance strategy inspired from one graph theory, where the local positions are estimated from optical sensors. To get the local positions, an integrated image processing method is developped. Firstly a mask-base is generated to store the features of NAOs, and a cross-correlation method is introduced to recognize the NAO. Subsequently, the distance and angle models are proposed to get the local information from a single image. Then, a visual compass is introduced to obtain the orientation of one NAO. After the local information exchange by the WiFi communication, a neighbor-check method is put foward to distinguish the homogeneous NAOs(all the NAOs look like the same). Further, a common frame is constructed as an artificial global frame, and straight non-intercrossing trajectories are planned according to the O(n log n) collision avoidance strategy. At last, the performance of our proposed local position-based method is verified by the simulations with up to 15 robots and the indoor experiments with 3 NAOs in a real environment. The convergence of the method has been demonstrated in both obstacle-free and static obstacle environments.

关键词： formation building a fleet of NAOs optical sensor visual compass local positions

Ubiquitination-mediated regulation of receptor-like kinases in symbiosis and immunity

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Molecular Plant 2024年第9期17卷 1335-1337页

作者： David Landry benoit Lefebvre Laboratory of Plant-Microbe-Environment Interactions(LIPME) Universite de ToulouseINRAECNRS31326 Castanet-TolosanFrance

Receptor-like kinases(RLKs)are plasma membrane(PM)proteins that monitor the extracellular environment and regulate various processes such as biotic *** motif(LysM)RLKs are a specific class of RLKs involved in the recognition of chitin-derived molecules produced by microorganisms(Buendia et al.,2018).Notably,the LysM-RLK heterocomplex LjNFR1/LjNFR5 recognizes lipochitooligosaccharides(LCOs,also called Nod factors)leading to root nodule symbiosis(RNS)in Lotus japonicus,whereas the heterocomplexes AtLYK5/AtCERK1 and OsCEBIP/OsCERK1 recognize chitooligosaccharides(COs)leading to defense responses in Arabidopsis thaliana and rice,respectively(Buendia et al.,2018).These receptors function as *** ligand binding activates the intracellular kinase activity of LjNFR1,AtCERK1,and OsCERK1,which mediate phosphorylation-dependent signaling *** mechanisms are essential to tightly control RLK homeostasis and signaling,allowing cells to respond efficiently while preventing constitutive *** PM-resident pool of RLKs must be maintained for rapid response,while RLK endocytosis and ultimately degradation in lytic vacuoles is critical for both signaling and downregulation of the *** addition to its role in proteasome-dependent degradation,ubiquitination,a post-translational protein modification,has emerged as a key regulator of PM proteins by inducing their internalization and degradation in lytic vacuoles(Romero-Barrios and Vert,2018).

关键词： extracellular immunity kinases

Eclipses and Occultations of Galilean Satellites Observed at Yunnan Observatory in 2003

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Chinese Journal of Astronomy and Astrophysics 2007年第2期7卷 317-324页

作者： Qing-Yu Peng benoit Noyelles Department of Computer Science Jinan University Guangzhou 5106321 Institut de mecanique celeste et de calcul des ephemerides - Observatoire de Paris UMR 8028 du CNRS 77 avenue Denfert-Rochereau F-75014 Paris France Joint Laboratory for Optical Astronomy Chinese Academyof Sciences Kunming 650011

We describe and analyze observations of mutual events of Galilean satellites made at the Yunnan Observatory in February 2003 from CCD imaging for the first time in China. Astrometric positions were deduced from these photometric observations by modelling the relative motion and the photometry of the involved satellites during each event.

关键词： planets and satellites individual Jupiter- astrometry - eclipse - occultation