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Journal of Modern Physics 2018年第6期9卷 1281-1290页

作者： Alexandre Chaloum Elbeze university pierre et marie curie Paris France

On September 14, 2015 09:50:45 UTC, the two laser interferometers of the LIGO program simultaneously observed a first gravitational wave signal called GW150914. With the commissioning of the VIRGO interferometer in 2017, two other detections, GW170814 and GW170817, were observed and their positions given accurately by LIGO and VIRGO. In this article, I argue that the photons circulating in the cavities of the three interferometers of LIGO and VIRGO were sensitive to the field of attraction of the planets of our Solar System and more particularly to that of the Sun, and would not be due to a coalescence of black hole or neutron stars. The shape of the signals obtained by my interaction model (called GEAR) between the photons in the interferometer cavity and the gravitational field of the Sun is very similar to that of a compact binary coalescence, identical to those obtained by general relativity. Solving the equations of GEAR also gives the exact positions and pseudo-date of the coalescences of all the LIGO and VIRGO detections detected so far, and probably those that will come at the end of 2018 and beyond.

关键词： Gravitational Energy Absorber Reactor GEAR Interferometer LIGO Interferometer VIRGO Law of Gravitation Gravitational Waves Expanding Universe Localization of Black-Hole GEAR Model

Hubble’s Constant and Flat Rotation Curves of Stars: Are Dark Matter and Energy Needed?

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Journal of Modern Physics 2017年第1期8卷 24-34页

作者： Alexandre Chaloum Elbeze university pierre et marie curie Paris France

Although dark energy and dark matter have not yet been detected, they are believed to comprise the majority of the universe. Observations of the flat rotation curve of galaxies may be explained by dark matter and dark energy. This article, using Newton’s laws and Einstein’s theory of gravitation, shows that it is possible to define a new term, called E0, variable in time and space, of which one of its limits is the Hubble constant H0. I show that E0?is strongly linked to an explanation of the flat rotation curve of galaxies. This strong correlation between Hubble’s constant H0?and E0 enables us to solve the mystery of the surplus of gravity that is stabilizing the universe.

关键词： Hubble’s Law General Relativity Cosmological Constant Expanding Universe Dark Energy

On the Numerical Solution to a Nonlinear Wave Equation Associated with the First Painlev Equation:an Operator-Splitting Approach

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Chinese Annals of Mathematics,Series B 2013年第2期34卷 237-254页

作者： Roland GLOWINSKI Annalisa QUAINI Department of Mathematics University of Houston4800 Calhoun RdHouston(TX) 77204USA Laboratoire Jacques-Louis Lions Universit Pierre et Marie Curie4Place Jussieu75252 Paris CEDEX 05France

The main goal of this article is to discuss the numerical solution to a nonlinear wave equation associated with the first of the celebrated Painlev'e transcendent ordinary differential *** order to solve numerically the above equation,whose solutions blow up in finite time,the authors advocate a numerical methodology based on the Strang's symmetrized operator-splitting *** this approach,one can decouple nonlinearity and differential operators,leading to the alternate solution at every time step of the equation as follows:(i) The first Painlevé ordinary differential equation,(ii) a linear wave equation with a constant *** that the space dimension is two,the authors consider a fully discrete variant of the above scheme,where the space-time discretization of the linear wave equation sub-steps is achieved via a Galerkin/finite element space approximation combined with a second order accurate centered time discretization *** handle the nonlinear sub-steps,a second order accurate centered explicit time discretization scheme with adaptively variable time step is used,in order to follow accurately the fast dynamic of the solution before it blows *** results of numerical experiments are presented for different coefficients and boundary *** show that the above methodology is robust and describes fairly accurately the evolution of a rather "violent" phenomenon.

关键词：非线性波动方程 Painlevé方程数值解法操作员 Galerkin 常微分方程分裂分离方法

On the Rayleigh-Plateau instability

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Applied Mathematics(A Journal of Chinese Universities) 2012年第2期27卷 127-138页

作者： Ali AL Riyabi Mohammed Boutat Sad Hilout Laboratoire de Mathématiques Université de PoitiersBoulevard Marie et Pierre CurieTéléport 2BP 3017986962 Futuroscope Chasseneuil cedexFrance

In this paper,we study the surface instability of a cylindrical pore in the absence of *** instability is called the Rayleigh-Plateau *** consider the model developed by Spencer et al.[18],Kirill et al.[10]and Boutat et al.[2]in the case without *** obtain a nonlinear parabolic PDE of order *** show the local existence and uniqueness of the solution of this problem by using Faedo-Galerkin *** main results are the global existence of the solution and the convergence to the mean value of the initial data for long *** tests are also presented in this study.

关键词： parabolic nonlinear partial differential equation initial boundary value problem local solution,uniqueness stability.

The High Light Response and Redox Control of Thylakoid FtsH Protease in Chlamydomonas reinhardtii

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Molecular Plant 2017年第1期10卷 99-114页

作者： Fei Wang Yafei Qi Alizee Malnoe Yves Choquet Francis-Andre Wollman Institut de Biologie Physico-Chimique Unite Mixte de Recherche 7141 Centre National de la Recherche Scientifique/Universite Pierre et Marie Curie Paris 75005 France

In Chlamydomonas reinhardtii, the major protease involved in the maintenance of photosynthetic machinery in thylakoid membranes, the FtsH protease, mostly forms large hetero-oligomers （-1 MDa） comprising FtsH1 and FtsH2 subunits, whatever the light intensity for growth. Upon high light exposure, the FtsH subunits display a shorter half-life, which is counterbalanced by an increase in FTSH1/2 mRNA levels, resulting in the modest upregulation of FtsH1/2 proteins. Furthermore, we found that high light increases the protease activity through a hitherto unnoticed redox-controlled reduction of intermolecular disulfide bridges. We iso- lated a Chlamydomonas FTSH1 promoter-deficient mutant, ftsh1-3, resulting from the insertion of a TOC1 transposon, in which the high light-induced upregulation of FTSH1 gene expression is largely lost. In ftsh1- 3, the abundance of FtsH1 and FtsH2 proteins are loosely coupled （decreased by 70% and 30%, respectively） with no formation of large and stable homo-oligomers. Using strains exhibiting different accumulation levels of the FtsH1 subunit after complementation of ftsh1-3, we demonstrate that high light tolerance is tightly correlated with the abundance of the FtsH protease. Thus, the response of Chlamydomonas to light stress involves higher levels of FtsH 1/2 subunits associated into large complexes with increased proteolytic activity.

关键词： chloroplast protease regulation of gene expression photoinhibition Chlamydomonas reinhardtii

Oxidized organic molecules in the tropical free troposphere over Amazonia

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National Science Review 2024年第1期11卷 174-184页

作者： Qiaozhi Zha Diego Aliaga Radovan Krejci Victoria A.Sinclair Cheng Wu Giancarlo Ciarelli Wiebke Scholz Liine Heikkinen Eva Partoll Yvette Gramlich Wei Huang Markus Leiminger Joonas Enroth Otso Per?kyl? Runlong Cai Xuemeng Chen Alkuin Maximilian Koenig Fernando Velarde Isabel Moreno Tuukka Pet?j? Paulo Artaxo Paolo Laj Armin Hansel Samara Carbone Markku Kulmala Marcos Andrade Douglas Worsnop Claudia Mohr Federico Bianchi Institute for Atmospheric and Earth System Research/Physics University of Helsinki Joint International Research Laboratory of Atmospheric and Earth System Sciences Nanjing University Department of Environmental Science & Bolin Centre for Climate Research Stockholm University Department of Chemistry and Molecular Biology University of Gothenburg Institute for Ion and Applied Physics University of Innsbruck Ionicon Analytik GmbH Laboratory for Atmospheric Physics Institute for Physics Research Universidad Mayor de San Andrés Institute of Physics University of Sao Paulo Institute for Geosciences and Environmental Research (IGE) University of Grenoble Alpes Agrarian Sciences Institute Federal University of Uberl?ndia Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical Technology Department of Atmospheric and Oceanic Sciences University of Maryland Aerodyne Research Inc. Department of Environmental System Science ETH Zürich Switzerland and Laboratory of Atmospheric Chemistry Paul Scherrer Institute

New particle formation(NPF) in the tropical free troposphere(FT) is a globally important source of cloud condensation nuclei, affecting cloud properties and climate. Oxidized organic molecules(OOMs)produced from biogenic volatile organic compounds are believed to contribute to aerosol formation in the tropical FT, but without direct chemical observations. We performed in situ molecular-level OOMs measurements at the Bolivian station Chacaltaya at 5240 m above sea level, on the western edge of Amazonia. For the first time, we demonstrate the presence of OOMs, mainly with 4–5 carbon atoms, in both gas-phase and particle-phase(in terms of mass contribution) measurements in tropical FT air from Amazonia. These observations, combined with air mass history analyses, indicate that the observed OOMs are linked to isoprene emitted from the rainforests hundreds of kilometers away. Based on particle-phase measurements, we find that these compounds can contribute to NPF, at least the growth of newly formed nanoparticles, in the tropical FT on a continental scale. Thus, our study is a fundamental and significant step in understanding the aerosol formation process in the tropical FT.

关键词： oxidized organic molecules tropical aerosol formation Amazon free troposphere

WTR:A Reputation Metric for Distributed Hash Tables Based on a Risk and Credibility Factor

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Journal of Computer Science & Technology 2009年第5期24卷 844-854页

作者： Xavier Bonnaire Erika Rosas Departamento de Informatica Universidad Tecnica Federico Santa MariaValparaisoChile Laboratoire d'Informatique de Paris 6 Universite Pierre et Marie CurieCNRS UMR 7606 INRIA REGALParisFrance

The growing number of popular peer to peer applications during the last five years has implied for researchers to focus on how to build trust in such very large scale distributed systems. Reputation systems have shown to be a very good solution to build trust in presence of malicious nodes. We propose in this paper a new metric for reputation systems on top of a Distributed Hash Table that uses a notion of risk to make the applications aware of certain behaviours of malicious nodes. We show that our metric is able to significantly reduce the number of malicious transactions, and that it also provides very strong resistance to several traditional attacks of reputations systems. We also show that our solution can easily scale, and can be adapted to various Distributed Hash Tables.

关键词： peer to peer reputation system risk evaluation

Asymptotic Behavior of a Structure Made by a Plate and a Straight Rod

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Chinese Annals of Mathematics,Series B 2013年第3期34卷 399-434页

作者： Dominique BLANCHARD Georges GRISO Universit de Rouen France Laboratoire J.-L. Lions-CNRS Boite courrier 187 Universit Pierre et Marie Curie 4 Place Jussieu 75005 Paris France

This paper is devoted to describing the asymptotic behavior of a structure made by a thin plate and a thin perpendicular rod in the framework of nonlinear elasticity. The authors scale the applied forces in such a way that the level of the total elastic energy leads to the Von-Krmn's equations (or the linear model for smaller forces) in the plate and to a one-dimensional rod-model at the limit. The junction conditions include in particular the continuity of the bending in the plate and the stretching in the rod at the junction.

关键词：弹性薄板渐近行为直杆结构线性模型非线性连续性交界处

Inducing neuronal regeneration and differentiation via the BDNF/ TrkB signaling pathway: a key target against neurodegenerative diseases?

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Neural Regeneration Research 2024年第3期19卷 495-496页

作者： Mirjana Antonijevic Patrick Dallemagne Christophe Rochais Normandie university UNICAENCERMNCaenFrance

Brain-derived neurotrophic factor(BDNF)is one of the neurotrophins,a specific polypeptide growth factor,which plays a crucial role in the proliferation,differentiation,survival,and death of neurons and non-neuronal *** is not only essential to maintain the balance between death on one side and survival of neurons on the other,but also it mediates additional higher-order activities such as learning,memory,and *** is initially synthesized as a precursor protein,proBDNF,that can be secreted as it is or it can be cleaved intracellularly by furin and proconvertases,or extracellularly by extracellular proteases such as matrix metalloprotease-9 and matrix metalloprotease-2,or plasmin to give mature BDNF.

关键词： death diseases degenerative

High-Resolution Crystal Structure and Redox Properties of Chloroplastic Triosephosphate Isomerase from Chlamydomonas reinhardtii

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Molecular Plant 2014年第1期7卷 101-120页

作者： Mirko Zaffagnini Laure Michelet Chiara Sciabolini Nastasia Di Giacinto Samuel Morisse Christophe H. Marchand Paolo Trost Simona Fermani Stephane D Lemaire Laboratoire de Biologie Moleculaire et Cellulaire des Eucaryotes FRE3354 Centre National de la Recherche Scientifique Universite Pierre et Marie Curie Institut de Biologie Physico-Chimique 13 rue Pierre et Marie Curie 75005 Paris France Laboratory of Plant Redox Biology Department of Pharmacy and Biotechnology (FaBiT) University of Bologna via Irnerio 42 40126 Bologna Italy Department of Chemistry 'G. Ciamician' University of Bologna via Selmi 2 40126 Bologna Italy

Triosephosphate isomerase （TPI） catalyzes the interconversion of glyceraldehyde-3-phosphate to dihydroxyacetone phosphate. Photosynthetic organisms generally contain two isoforms of TPI located in both cytoplasm and chloroplasts. While the cytoplasmic TPI is involved in the glycolysis, the chloroplastic isoform participates in the Calvin-Benson cycle, a key photosynthetic process responsible for carbon fixation. Compared with its cytoplasmic counterpart, the functional features of chloroplastic TPI have been poorly investigated and its three-dimensional structure has not been solved. Recently, several studies proposed TPI as a potential target of different redox modifications including dithiol/disulfide interchanges, glutathionylation, and nitrosylation. However, neither the effects on protein activity nor the molecular mechanisms underlying these redox modifications have been investigated. Here, we have produced recombinantly and purified TPI from the unicellular green alga Chlamydomonas reinhardtii （Cr）. The biochemical properties of the enzyme were delineated and its crystallographic structure was determined at a resolution of 1.1 A. CrTPI is a homodimer with subunits containing the typical （β/α）8-barrel fold. Although no evidence for TRX regulation was obtained, CrTPI was found to undergo glutathionylation by oxidized glutathione and trans-nitrosylation by nitrosoglutathione, confirming its sensitivity to multiple redox modifications.

关键词： triosephosphate isomerase three-dimensional structure TIM-barrel thiol-based redox regulation transnitrosylation.