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Efficient Numerical Computation of Time-Fractional Nonlinear Schrodinger Equations in Unbounded Domain

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Communications in Computational Physics 2019年第1期25卷 218-243页

作者： Jiwei Zhang Dongfang Li xavier Antoine Beijing Computational Science Research Center Beijing 100193P.R.China School of Mathematics and Statistics Huazhong University of Science and TechnologyWuhan 430074China Hubei Key Laboratory of Engineering Modeling and Scientific Computing Huazhong University of Science and TechnologyWuhan 430074China Institut Elie Cartan de Lorraine UMR CNRS 7502Universit́e de LorraineInria Nancy-Grand EstSPHINX TeamF-54506 Vandoeuvre-l`es-Nancy CedexFrance

The aim of this paper is to derive a stable and efficient scheme for solving the one-dimensional time-fractional nonlinear Schrodinger equation set in an unbounded *** first derive absorbing boundary conditions for the fractional system by using the unified approach introduced in[47,48]and a linearization ***,the initial boundary-value problem for the fractional system with ABCs is discretized,a stability analysis is developed and the error estimate O(h^(2)+τ)is *** accel-erate the L1-scheme in time,a sum-of-exponentials approximation is introduced to speed-up the evaluation of the Caputo fractional *** resulting algorithm is highly efficient for long time ***,we end the paper by reporting some numerical simulations to validate the properties(accuracy and efficiency)of the derived scheme.

关键词： Time-fractional nonlinear Schrodinger equation absorbing boundary condition sta-bility analysis convergence analysis sum-of-exponentials approximation

Second-Kind Boundary Integral Equations for Scattering at Composite Partly Impenetrable Objects

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Communications in Computational Physics 2018年第1期23卷 264-295页

作者： xavier Claeys Ralf Hiptmair Elke Spindler Sorbonne Universites UPMC Univ Paris 06CNRSINRIAUMR 7598Laboratoire Jacques-Louis Lionsequipe AlpinesF-75005ParisFrance Seminar for Applied Mathematics Swiss Federal Institute of TechnologyCH-8092 ZurichSwitzerland

We consider acoustic scattering of time-harmonic waves at objects composed of several homogeneous *** of those may be impenetrable,giving rise to Dirichlet boundary conditions on their *** start from the recent secondkind boundary integral approach of[***,and ***,and ***.A second-kind Galerkin boundary element method for scattering at composite *** Numerical Mathematics,55(1):33-57,2015]for pure transmission problems and extend it to settings with essential boundary *** on so-called global multipotentials,we derive variational second-kind boundary integral equations posed in L^(2)(S),where S denotes the union of material *** suppress spurious resonances,we introduce a combined-field version(CFIE)of our new *** numerical tests highlight the low andmesh-independent condition numbers of Galerkin matrices obtained with discontinuous piecewise polynomial boundary element *** also confirm competitive accuracy of the numerical solution in comparison with the widely used first-kind single-trace approach.

关键词： Acoustic scattering second-kind boundary integral equations Galerkin boundary element methods

A Construction of Beam Propagation Methods for Optical Waveguides

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Communications in Computational Physics 2009年第8期6卷 565-576页

作者： xavier Antoine Pierre Dreyfuss Karim Ramdani Institut Elie Cartan Nancy Nancy-UniversiteCNRSINRIACORIDA TeamBoulevard des Aiguillettes B.P.239 F-54506 Vandoeuvre-les-NancyFrance Laboratoire J.A.Dieudonne(Mathematiques) Universite de Nice-Parc Valrose06000 NiceFrance INRIA CORIDA Teamand Institut Elie Cartan NancyNancy-UniversiteCNRSINRIABoulevard des Aiguillettes B.P.239 F-54506 Vandoeuvre-les-NancyFrance

This paper presents a systematic method to derive Beam Propagation Models for optical *** technique is based on the use of the symbolic calculus rules for pseudodifferential *** cases of straight and bent optical wave... 详细信息

关键词： Bent waveguides Beam Propagation Method optics

G protein-coupled receptor 37(GPR37) emerges as an important modulator of adenosinergic transmission in the striatum

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Neural Regeneration Research 2019年第11期14卷 1912-1914页

作者： xavier Morato Rodrigo A. Cunha Francisco Ciruela Unitat de Farmacologia Departament Patologia i Terapeutica ExperimentalFacultat de MedicinaInstituto de Investigacion Biomedica de Bellvitge (IDIBELL)Universitat de BarcelonaL’Hospitalet de LlobregatBarcelonaSpainInstitut de NeurocienciesUniversitat de BarcelonaBarcelonaSpain (Morato X Ciruela F) Center for Neuroscience and Cell Biology (CNC)-Center for Neurosciences and Cell BiologyUniversity of CoimbraCoimbraPortugalFaculty of MedicineUniversity of CoimbraCoimbraPortugal

G protein-coupled receptor 37 (GPR37), also known as parkin associated endothelin-like (Pael) receptor, is an orphan G protein- coupled receptor, which suffers a defective parking ubiquitination in autosomal recessive Parkinson’s disease promoting its endoplasmic reticulum aggregation and stress, neurotoxicity and neuronal death (Takahashi and Imai, 2003). Interestingly, we have demonstrated previously that GPR37 heteromerizes with adenosine A2A receptor (A2AR) in the striatum (Morato et al., 2017;Sokolina et al., 2017).

关键词： G protein-coupled receptor 37(GPR37) important modulator adenosinergic transmission

Cleaning of Marine Sediment Samples for Large Diatom Stable Isotope Analysis

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Journal of Earth Science 2012年第2期23卷 161-172页

作者：熊志方李铁刚 xavier Crosta Key Laboratory of Marine Geology and Environment Institute of OceanologyChinese Academy of Sciences UMR-CNRS 5805 EPOC UniversitéBordeaux 1Avenue des Facultés

Diatom stable isotope analysis offers considerable potential in palaeoceanography, par-ticularly where carbonate material is scarce or absent. However, extracting pure diatom frustules free of external labile organic matter from marine sediments is an essential requirement for their applica-tions as paleoenvironmental proxies. Here, based largely on previous work, we developed a method in-cluding physical separation and chemical oxidation steps to concentrate and clean pure large diatoms from laminated diatom mat and diatomaceous clay sediment samples for their stable isotope analysis. Using the physical separation techniques consisting of the removal of carbonate and excess organic matter, sieving, differential settling, and heavy liquid floatation, pure diatoms can be successfully iso-lated from the sediment samples with opal concentration more than 10%. Subsequent time oxidation experiment shows that labile organic matter coating pure diatom valves can be effectively removed with 30% H2O2 at 65 ℃ for 2 h. Measurements of δ13C after every step of physical separation demonstrate that contaminants and lost diatoms can influence the original diatom stable isotope signal, highlighting the importance of a visual check for dominant diatom size in the initial sample and purity in the final sample. Although the protocol described here was only applied to diatom mats or diatom oozes con-taining large diatoms （Ethmodiscus rex）, we believe that this method can be adapted to common dia-toms of general marine sediment samples.

关键词： large diatom stable isotope physical separation chemical oxidation Parece Vela basin palaeoceanography.

Cold acclimation increases Asian citrus psyllid Diaphorina citri (Hemiptera: Liviidae) survival during exposure to freezing temperatures

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Insect Science 2022年第2期29卷 531-538页

作者： xavier Martini Kathi Malfa Dara Stockton Monique JRivera Department of Entomology and Nematology North Florida Research and Education CenterQuincyFloridaUSA USDA-ARS U.S.Pacific Basin Agricultural Research CenterHiloHawaiiUSA Department of Entomology University of CaliforniaRiversideCaliforniaUSA

The Asian citrus psyllid,Diaphorina citri,is the vector of the pathogenic bacteria that causes Huanglongbing,the most devasting disease affecting citrus *** cultivation of citrus tends to expand northward,the tolerance of psyllids to freezing temperatures needs to be *** mortality of *** to cold temperature has been previously studied,much less is known regarding the acclimation potential of psyllids to cold *** first evaluated cold resistance of *** depending on color morph and ***,we compared mortality of *** at−4°C for 10 hours between unacclimated psyllids,psyllids that were gradually acclimated to cold over 1 or 2 weeks,and psyllids intermittently acclimated also for 1 or 2 *** did not find major differences in cold resistance between color morphs and *** found that after 1 week of gradual acclimation,the survival of psyllids at−4°C increased to 86%,compared to 20%in the control *** did not increase after the second week of gradual *** intermittent acclimation improved survival compared to the control group,it was less effective than gradual acclimation with a survival at 30%and 70%after 1 and 2 weeks of acclimation,respectively,although this difference with gradual acclimation was not significant at week *** data show that gradual cold acclimation allows *** to survive brief periods below *** may serve as a mechanism responsible for increasing northern establishment of this pest.

关键词： cold acclimation cold hardy citrus cold resistance citrus greening Diaphorina citri overwintering

Limiting Factors for Active Suppression of Structural Chatter Vibrations Using Machine′s Drives

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Transactions of Nanjing University of Aeronautics and Astronautics 2017年第4期34卷 341-348页

作者： xavier Beudaert Asier Barrios Kaan Erkorkmaz Jokin Munoa Dynamics and Control Precision Controls Laboratory University of Waterloo

Chatter vibrations are a major limitation for rough milling operations,leading to productivity reduction,low tool life and poor surface *** has been shown recently that the machine tool′s own drives can be used to increase the stability limit related to structural modes of the *** damp the low frequency modes,a new feedback loop is added to the classical position,velocity and current cascaded *** objective of this study is to analyse the limitations of this new chatter suppression *** related to the non-collocated control are first studied on a simplified three-mass model and then experimentally demonstrated on a three-axis horizontal milling *** industrial integration of the new control loop with sampling time constraints and limited drive′s bandwidth is *** determining the appropriate conditions to use this chatter suppression technique,a cutting test demonstrates that the stability limit can be doubled in the low regions of the stability lobes.

关键词： chatter control damping milling

Bioskin: A New Biomaterial for Therapeutical and Biotechnological Purposes

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复旦学报（自然科学版） 2005年第5期44卷 796-797页

作者： xavier-Filho L Laboratório de Produtos Naturais e Biotecnologia Instituto de Tecnologia e Pesquisa-ITP Universidade Tiradentes-UNIT Aracaju Sergipe Brazil

Bioskin is new material by Acetobacter xylinum, Saccharomyces cerevisae and Schyzosaccharomyces pombe in mixed culture on sucrose. The Material has been revealed as hypoaller- genic,antibiotic,antithermic and sedative. It is widely used for skin regeneration in therapy of burns as well as in odontological *** contains high amounts of D-glucosamine and N-acetyl-D-glucosamine. It does not produce ash after heating at 600 ℃ and its combustion heat is similar to that of several current woods, such as pine oak or maple Bioskin has been used to immobilize algal cells, fungal spores and Bacteria in order to study some metabolic events. In addition, immobilization, of several enzymes has been performed using bioskin as inert *** was immobilized at pH 7.0 by ionic adsorption (aminosugars provide a net positive charge neutral pH values) whereas several glycoproteins can be immobilized on bioskin by an affinity mechanism.

关键词：生物素生物材料微生物酵母生物聚合体

Effect of an adverse pressure gradient on the streamwise Reynolds stress profile maxima in a turbulent boundary layer

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Acta Mechanica Sinica 2013年第3期29卷 395-398页

作者： Wei Ma xavier Ottavy Li-Peng Lu Francis Leboeuf Laboratoire de Mécanique des Fluides et d'Acoustique Ecole Centrale de Lyon School of Jet Propulsion Beihang University

It is widely accepted that in a turbulent boundary layer （TBL） with adverse pressure gradient （APG） an outer peak usually appears in the profile of streamwise Reynolds stress. However, the effect of APG on this outer peak is not clearly understood. In this paper, the effect of APG is analysed using the numerical and experimental results in the literature. Because the effect of upstream flow is inherent in the TBL, we first analyse this effect in TBLs with zero pressure gradient on flat plates. Under the individual effect of upstream flow, an outer peak already appears in the profile of streamwise Reynolds stress when the TBL continues developing in the streamwise direction. The APG accelerates the appearance of the outer peak, instead of being a trigger.

关键词： Turbulent boundary layer · Pressure gradient · Reynolds stress