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A Megatheropod Tooth from the Early Cretaceous of Fusui, Guangxi, Southern China

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Acta Geologica Sinica(English Edition) 2014年第1期88卷 6-12页

作者： MO Jinyou HUANG Chaolin XIE Shaowen Buffetaut ERIC Natural History Museum of Guangxi CNRS UMR 8538 Laboratoire de Geologie de l'Ecole Normale Superieure

A nearly complete right maxillary or left dentary tooth（NHMG 10858） from the Lower Cretaceous Xinlong Formation of the Napai Basin, Fusui County, Guangxi, southern China, is described. The tooth is large in size, with a CBL of 37 mm. Given the geological age and its crown morphology, including the size, it is most likely that the tooth belongs to a carcharodontosaurid. The recovered specimen represents one of the largest theropod teeth hitherto reported from the Early Cretaceous of Asia.

关键词： Tooth Theropoda Xinlong Formation Early Cretaceous Napai Basin Guangxi

Coupled Optical Solitons for Pulse Propagation in Multi-Level Media

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Chinese Physics Letters 2006年第4期23卷 834-837页

作者：黄国翔 Jacob Szeftel department of Physics East China Normal University Shanghai 200062 laboratoire de Photonique Quantique et Moleculaire Ecole Normale Superieure de Cachan Cachan France

We investigate the shape-preserving propagation of N optical pulses in an （N ＋ 1）-level medium. We solve Maxwell-Schroedinger equations exactly and provide several types of explicit coupled soliton solutions, which... 详细信息

关键词： ELECTROMAGNETICALLY INDUCED TRANSPARENCY SELF-INDUCED TRANSPARENCY COLD3-STATE MEDIUM SLOW-LIGHT ULTRASLOW BRIGHT 3-LEVEL MEDIUM DARK SOLITONS LASER AMPLIFICATION QUANTUM

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

Local Dispersive and Strichartz Estimates for the Schr?dinger Operator on the Heisenberg Group

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Communications in Mathematical Research 2023年第1期39卷 1-35页

作者： Hajer Bahouri Isabelle Gallagher CNRS&Sorbonne Universite laboratoire Jacques-Louis Lions(LJLL)UMR 75984 Place Jussieu 75005 ParisFrance DMA Ecole Normale SuperieureCNRSPSL Research University75005 ParisFrance UFR de Mathematiques Universitéde Paris75013 ParisFrance

It was proved by Bahouri et al.[9]that the Schrodinger equation on the Heisenberg group H^(d),involving the sublaplacian,is an example of a totally non-dispersive evolution equation:for this reason global dispersive estimates cannot *** paper aims at establishing local dispersive estimates on H^(d) for the linear Schrodinger equation,by a refined study of the Schrodinger ker-nel St on H^(d).The sharpness of these estimates is discussed through several *** approach,based on the explicit formula of the heat kernel on H^(d) derived by Gaveau[19],is achieved by combining complex analysis and Fourier-Heisenberg *** a by-product of our results we establish local Stri-chartz estimates and prove that the kernel St concentrates on quantized hori-zontal hyperplanes of H^(d).

关键词： Heisenberg group Schrodinger equation dispersive estimates Strichartz estimates

Auger effect in weakly confined nanocrystals

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光:科学与应用(英文版) 2023年第8期12卷 1454-1456页

作者： Jiawen Liu Laurent Coolen laboratoire de Physique de I'ecole normale superieure ENSUniversite PSLCNRSSorbonne UniversiteUniversite Paris CiteF-75005 ParisFrance Sorbonne Universite CNRSInstitut de NanoSciences de ParisINSPF-75005 ParisFrance

An extensive analysis of biexciton luminescence in high-quality,large perovskite CsPbBr_(3) nanocrystals shows how the biexciton Auger decay rate deviates from the"universal"volume scaling as the exciton confinement b... 详细信息

关键词： weakly confined perovskite

Zn Doping Effect on Magnetic Properties of Znx Cdl-xCr2S4 Systems by High-Temperature Series Expansions

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Chinese Physics Letters 2007年第7期24卷 2077-2080页

作者： M. Hamedoun R. Masrour K. Bouslykhane A. Hourmatallah N. Benzakour A. Filali laboratoire de Physique du Solide Universite Sidi Mohammed Ben Abdellah Facult~ des sciences Dhar Mahraz BP 1796 Fes Morocco Equipe de Physique du Solide Ecole Normale Superieure BP 5206 Bensouda Fes Morocco

The effect of Zn doping on the magnetic properties of CdCr2S4 systems is studied by mean field theory and high-temperature series expansion （HTSE）. The nearest neighbouring and the next-neighbouring super-exchange interactions Jl（x） and J2（x） are evaluated for the spinel system Zn, Cd1-xCr2S4 in the range 0 〈 x 〈 1. The intra-planar and the inter-planar interactions are deduced. The HTSE combined with the Padd approximant method （PA） is applied to the spinel system ZnxCdl-,Cr2S4. The magnetic phase diagram, i.e. Tc versus dilution x, is obtained. The critical exponents associated with the magnetic susceptibility 7 and the correlation length u are deduced. The obtained theoretical results are in agreement with the experimental data obtained by magnetic measurements.

关键词： Magnetic Properties High-Temperature HTSE

Recovering Navier–Stokes Equations from Asymptotic Limits of the Boltzmann Gas Mixture Equation

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Communications in Theoretical Physics 2016年第5期65卷 553-562页

作者： Carlo Bianca Christian Dogbe laboratoire de Physique Statistique Ecole Normale Superieure PSL Research University University Paris Diderot Sorbonne Paris-Cite Sorbonne Universites UPMC Univ Paris 06 CNRS department of Mathematics Universite de Caen Normandie LMNOCNRS

This paper is devoted to the derivation of macroscopic fluid dynamics from the Boltzmann mesoscopic dynamics of a binary mixture of hard-sphere gas *** the hydrodynamics limit is performed by employing different time and space *** paper shows that,depending on the magnitude of the parameters which define the scaling,the macroscopic quantities(number density,mean velocity and local temperature)are solutions of the acoustic equation,the linear incompressible Euler equation and the incompressible Navier–Stokes *** derivation is formally tackled by the recent moment method proposed by[***,et al.,***.63(1991)323]and the results generalize the analysis performed in[***,et al.,*** ***.29(2015)240].

关键词：斯托克斯方程 Navier-Stokes方程混合方程极限可压缩Euler方程 Boltzmann 玻尔介观动力学

CONVERGENCE OF NUMERICAL SCHEMES FOR A CONSERVATION EQUATION WITH CONVECTION AND deGENERATE DIFFUSION

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Journal of Computational Mathematics 2021年第3期39卷 428-452页

作者： R.Eymard C.Guichard Xavier Lhebrard Universite Gustave Eiffel Laboratoire d'nalyse et de Mathematiques Appliquees(UMR 8050)UGEUPECCNRSF-77454Mame-la-ValleeFrance Sorbonne Universite Universite Paris-Diderot SPCCNRSInriaLaboratoire Jacques-Louis Lionsequipe ANGEF-75005 Paris ecole normale superieure de Rennes France

The approximation of problems with linear convection and degenerate nonlinear difFusion,which arise in the framework of the transport of energy in porous media with thermodynamic transitions,is done usingθ-scheme based on the centred gradient discretisation *** convergence of the numerical scheme is proved,although the test functions which can be chosen are restricted by the weak regularity hypotheses on the convection field,owing to the application of a discrete Gronwall lemma and a general result for the time translate in the gradient discretisation *** numerical examples,using both the Control Volume Finite Element method and the Vertex Approximate Gradient scheme,show the role ofθfor stabilising the scheme.

关键词： Linear convection degenerate diffusion Gradient discretisation method θ-scheme

Influence of nitrogen sources on growth and mycotoxin production by isolates of Pyrenophora tritici-repentis from wheat

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The Crop Journal 2016年第2期4卷 119-128页

作者： Noureddine Bouras Michael D.Holtz Reem Aboukhaddour Stephen E.Strelkov department of Agricultural Food and Nutritional Science410 Agriculture/Forestry CentreUniversity of Alberta laboratoire de Biologie des Systemes Microbiens(LBSM) Ecole Normale Superieure de KoubaAlgiersAlgeria departement de Biologie Faculte des Sciences de la Nature et de la Vie et Sciences de la TerreUniversite de Ghardaia Field Crop development Centre Alberta Agriculture and Food

The fungus Pyrenophora tritici-repentis(Died.) Drechs. infects the leaves and kernels of wheat,causing tan spot and red smudge, respectively. Isolates of P. tritici-repentis have been reported to be both phytopathogenic and mycotoxigenic. This research investigates the influence of nitrogen sources on growth and production of mycotoxins by eight different isolates of P. tritici-repentis. A synthetic agar medium(SAM) was used with different nitrogen sources, both inorganic [(NH4Cl, NH4NO3and(NH4)2SO4)] and organic(L-alanine, L-histidine, and L-lysine), at a concentration of 37.5 mmol L-1. Individual isolates exhibited different growth rates that varied according to the nitrogen source added to the medium. The choice of nitrogen source also had a major effect on production of the mycotoxins emodin, catenarin and islandicin. The highest concentrations of emodin, 54.40 ± 4.46 μg g-1, 43.07 ± 23.39 μg g-1and28.91 ± 4.64 μg g-1of growth medium, were produced on the complex medium(V8-potato dextrose agar) by the isolates Alg-H2, 331-2 and TS93-71 B, respectively. A relatively high concentration of emodin also was produced by isolates Az35-5(28.29 ± 4.71 μg g-1of medium)and TS93-71B(27.03 ± 4.09 μg g-1of medium) on synthetic medium supplemented with L-alanine. The highest concentrations of catenarin(174.54 ± 14.46 μg g-1and 104.87 ±6.13 μg g-1of medium) were recorded for isolates TS93-71 B and Alg-H2 on synthetic medium supplemented with L-alanine and NH4 Cl, respectively. The highest concentration of islandicin(4.64 ± 0.36 μg g-1medium) was observed for isolate 331-2 in the presence of L-lysine. There was not a close relationship between mycelial growth and mycotoxin production by the fungal isolates. This is the first report on the influence of nitrogen sources on the production of mycotoxins by P. tritici-repentis.

关键词： Catenarin Emodin Islandicin Nitrogen source Tan spot Triticum aestivum