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Raman-Brillouin interplay for inertial confinement fusion relevant laser-plasma interaction

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High Power Laser Science and Engineering 2016年第3期4卷 23-38页

作者： C.Riconda S.Weber LULI-upmc universitparis 6:Sorbonne universits CNRSEcole PolytechniqueCEA:Universit Paris-Saclay Institute of Physics of the ASCR

The co-existence of the Raman and Brillouin backscattering instability is an important issue for inertial confinement fusion. The present paper presents extensive one-dimensional(1D) particle-in-cell(PIC) simulations for a wide range of parameters extending and complementing previous findings. PIC simulations show that the scenario of reflectivity evolution and saturation is very sensitive to the temperatures, intensities, size of plasma and boundary conditions employed. The Langmuir decay instability is observed for rather small k_(epw)λ_D but has no influence on the saturation of Brillouin backscattering, although there is a clear correlation of Langmuir decay instability modes and ion-fractional decay for certain parameter ranges. Raman backscattering appears at any intensity and temperature but is only a transient phenomenon. In several configurations forward as well as backward Raman scattering is observed. For the intensities considered, I λ_o^2 above 10^(15) W μm^2/cm^2, Raman is always of bursty nature. A particular setup allows the simulation of multi-speckle aspects in which case it is found that Raman is self-limiting due to strong modifications of the distribution function. Kinetic effects are of prime importance for Raman backscattering at high temperatures. No unique scenario for the saturation of Raman scattering or Raman–Brillouin competition does exist. The main effect in the considered parameter range is pump depletion because of large Brillouin backscattering. However, in the low k_(epw)λ_D regime the presence of ion-acoustic waves due to the Langmuir decay instability from the Raman created electron plasma waves can seed the ion-fractional decay and affect the Brillouin saturation.

关键词： Brillouin backscattering inertial confinement fusion kinetic effects laser-plasma interaction parametric instabilities particle-in-cell simulations Raman backscattering

A Family of Methods of the DG-Morley Type for Polyharmonic Equations

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Advances in Applied Mathematics and Mechanics 2010年第3期2卷 303-332页

作者： Vitoriano Ruas Jose Henrique Carneiro De Araujo upmc-univ.paris 6 UMR7190 Inst.Jean Le Rond d’Alembert/CNRSParisFrance Visiting Professor at Graduate School of Computer ScienceUniversidade Federal FluminenseNiteròiRJBrazil Department and Graduate School of Computer Science Universidade Federal FluminenseNiteròiRJBrazil

Discontinuous Galerkin methods as a solution technique of second order elliptic problems,have been increasingly exploited by several authors in the past ten *** is generally claimed the alledged attractive geometrical flexibility of these methods,although they involve considerable increase of computational effort,as compared to continuous *** work is aimed at proposing a combination of DGM and non-conforming finite element methods to solve elliptic m-harmonic equations in a bounded domain of R^(n),for n=2 or n=3,with m≥n+1,as a valid and reasonable alternative to classical finite elements,or even to boundary element methods.

关键词： Discontinuous Galerkin finite elements Hermite tetrahedrons Morley triangle non-conforming polyharmonic equations

Crosstalk between androgen signaling and the chemokine receptor CXCR4:a novel strategy to promote myelin regeneration

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Neural Regeneration Research 2025年第9期20卷 2581-2582页

作者： Marianne Bardy-Lagarde Narimène Asbelaoui Abdel Mouman Ghoumari UMR1195 “Diseases and Hormones of the Nervous System”Inserm and University Paris-SaclayKremlin-BicêtreFrance

Multiple sclerosis(MS)is the most common chronic disease of the central nervous system(CNS)in young adults and represents the first cause of severe handicap,originally non-traumatic(Oh et al.,2018).MS is chara cterized by the infiltration of auto reactive lymphocytes specific to myelin through the blood-brain barrier,which results in the appearance of inflammatory demyelinating lesions caused by the death of the central nervous system myelinating cells,oligodendrocytes(Oh et al.,2018).There is a prevalence sexual with a ratio of three times more affected women than men.

关键词： myelin CXCR4

Solving the Dyson-Schwinger equation around its first singularities in the Borel plane

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Frontiers of physics 2016年第6期11卷 25-30页

作者： Clavier, Pierre J. Bellon, Marc P. Sorbonne universites UPMC Univ Paris 06 UMR 7589 LPTHE Paris France CNRS UMR 7589 LPTHE Paris France

The Dyson-Schwinger equation of the massless Wess-Zumino model is written as an equation over the anomalous dimension of the theory. Its asymptotic behavior is derived and the procedure to compute the perturbations of this asymptotic behavior is detailed. This procedure uses ill-defined objects. To solve this, the Dyson-Schwinger equation is rewritten for the Borel plane. It is shown that the ill- defined procedure in the physical plane can be applied in the Borel plane. Other results obtained in the Borel plane are stated and the proof for one result is described.

关键词： Dyson-Schwinger equation Wess-Zumino model Borel transform

Consequence of shape elongation on emission asymmetry for colloidal CdSe/CdS nanoplatelets

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Nano Research 2018年第7期11卷 3593-3602页

作者： Fu Fengt Loan Thu Nguyen Michel Nasilowski Brice Nadal Benoit Dubertret Laurent Coolent Agnes Maitre Sorbonne universites UPMC Univ Paris 06 CNRS-UMR 7588 Institut des NanoSciences de Paris F-75005 Paris France Institute of Materials Science Vietnam Academy of Science and Technology 18 Hoang Quoc Viet Road Cau Giay Dist. 100000 Hanoi Vietnam Laboratoire de Physique et d'Etude des Materiaux ESPCI UPMC Univ Paris 6 CNRS 10 rue Vauquelin F-75005 Paris France

In this paper, we demonstrate that for colloidal CdSe/CdS nanoplatelets, a rectangular shape induces emission asymmetry, in terms of both polarization and emission patterns. Polarimetry and emission pattern analyses are combined to provide information on the orientation of the transition dipoles involved in the nanoplatelet emission. It is shown that for rectangular nanoplatelets, the emission is polarized and the emission patterns are anisotropic, whereas they remain nonpolarized and isotropic for square nanoplatelets. This can be appropriately described by the dielectric antenna effect induced by the elongated shape of the rectangular platelet.

关键词： colloidal semiconductor nanoplatelet emission dipole emission polarization emission pattern

Expression and modulation of neuroligin and neurexin in the olfactory organ of the cotton leaf worm Spodoptera fittoralis

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Insect Science 2017年第2期24卷 210-221页

作者： Nicolas Durand Thomas Chertemps Francoise Bozzolan Martine Maibeche Sorbonne universites upmc - univ.paris 06 Institut d'Ecologie et des Sciences de 'Environnement de Paris INRA CNRS IRD UPECD6partement d'Ecologie Sensorielle F-75252 Paris France

Carboxylesterases are enzymes widely distributed within living organisms. In insects, they have been mainly involved in dietary metabolism and detoxification function. Interestingly, several members of this family called carboxylesterase-like ad- hesion molecules （CLAMs） have lost their catalytic properties and are mainly involved in neuro/developmental functions. CLAMs include gliotactins, neurotactins, glutactins, and neuroligins. The latter have for binding partner the neurexin. In insects, the function of these proteins has been mainly studied in Drosophila central nervous system or neuro- muscular junction. Some studies suggested a role of neuroligins and neurexin in sensory processing but CLAM expression within sensory systems has not been investigated. Here, we reported the identification of 5 putative CLAMs expressed in the olfactory system of the model pest insect Spodoptera littoralis. One neuroligin, Slnlg4-yll and its putative binding partner neurexin Slnrxl were the most expressed in the antennae and were surprisingly associated with olfactory sensilla. In addition, both transcripts were upregulated in male antennae after mating, known to modulate the sensitivity of the peripheral olfactory system in S. littoralis, suggesting that these molecules could be involved in sensory plasticity.

关键词： carboxylesterase-like adhesion molecules insect neurexin neuroligins olfaction

Alien calculus and non perturbative effectsin Quantum Field Theory

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Frontiers of physics 2016年第6期11卷 31-34页

作者： Marc P. Bellon Sorbonne universites UPMC Univ Paris 06 UMR 7589 LPTHE 75005 Paris France CNRS UMR 7589 LPTHE 75005 Paris France

In many domains of physics, methods for dealing with non-perturbative aspects are required. Here, I want to argue that a good approach for this is to work on the Borel transforms of the quantities of interest, the singularities of which give non-perturbative contributions. These singularities in many cases can be largely determined by using the alien calculus developed by Jean Écalle. My main example will be the two point function of a massless theory given as a solution of a renormalization group equation.

关键词： Schwinger–Dyson equations series resommation alien calculus

Egg CD9 protein tides correlated with sperm oscillations tune the gamete fusion ability in mammal

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Journal of Molecular Cell Biology 2018年第6期10卷 494-502页

作者： Benjamin Ravaux Sophie Favier Eric Perez and Christine Gourier Laboratoire de Physique Statistique Ecole Normale Superieure/PSL Research UniversityUPMC Univ Paris 06Universite Paris DiderotCNRS75005 ParisFrance

Mammalian fertilization involves membrane events-adhesion,fusion,sperm engulfment,membrane block to polyspermy-whose causes remain largely ***,specific oscillations of the sperm in contact with the egg were shown to be necessary for *** a microfluidic chip to impose the venue for the encounter of two gametes allowed real-time observation of the membrane remodelling occurring at the sperm/egg *** spatiotemporal mapping of egg CD9 revealed that this protein concentrates at the egg/sperm interface as a result of sperm oscillations,until a CDg-rich platform is nucleated on which fusion immediately takes *** 2-5 min after fusion,most of the CD9 leaves the egg for the external aqueous *** an egg membrane wave engulfs the sperm head in^25 *** results show that sperm oscillations initiate the CD9 recruitment that causes gamete fusion after which CD9 and associated proteins leave the membrane in a process likely to contribute to block *** highlight that the gamete fusion story in mammals is an unexpected interplay between mechanical constraints and proteins.

关键词： mammalian fertilization membrane dynamics real-time imaging CDg sperm oscillations gamete fusion

Micro-arcsecond Celestial Reference Frames:definition and realization——Impact of the recent IAU Resolutions

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Research in Astronomy and Astrophysics 2012年第8期12卷 1162-1184页

作者： Nicole Capitaine SYRTE Observatoire de ParisCNRSUPMC61 avenue de l’Observatoire75014ParisFrance

The adoption of the International Celestial Reference System （ICRS）, based on Very Long Baseline Interferometry （VLBI） observations of extragalactic radiosources by the International Astronomical Union （IAU） since 1998 January 1, opened a new era for astronomy. The ICRS and the corresponding frame, the International Celestial Reference Frame （ICRF）, replaced the Fundamental Catalog （FK5） based on positions and proper motions of bright stars, with the Hipparcos cat- alog being adopted as the primary realization of the ICRS in optical wavelengths. According to its definition, the ICRS is such that the barycentric directions of distant extragalactic objects show no global rotation with respect to these objects; this pro- vides a quasi-inertial reference for measuring the positions and angular motions of the celestial objects. Other resolutions on reference systems were passed by the IAU in 2000 and 2006 and endorsed by the International Union of Geodesy and Geophysics （IUGG） in 2003 and 2007, respectively. These especially concern the definition and re- alization of the astronomical reference systems in the framework of general relativity and transformations between them. First, the IAU 2000 resolutions refined the con- cepts and definition of the astronomical reference systems and parameters for Earth＇s rotation, and adopted the IAU 2000 precession-nutation. Then, the IAU 2006 resolutions adopted a new precession model that is consistent with dynamical theories; they also addressed definition, terminology or orientation issues relative to reference systems and time scales that needed to be specified after the adoption of the IAU 2000 resolutions. An additional IUGG 2007 resolution defined the International Terrestrial Reference System （ITRS） so that it strictly complies with the IAU recommendations. Finally, the IAU 2009 resolutions adopted a new system of astronomical constants and an improved realization of the ICRF. These fundamental changes have led to significant

关键词： astrometry and celestial mechanics: astrometry -- reference systems --Earth -- techniques: interferometric