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Science China Chemistry 2010年第9期53卷 1932-1936页

作者： MONDON Martine LEN christophe UMR 6514 Université de Poitiers CNRS Synthèse et Réactivité des Substances Naturelles EA4297 Université de Technologie de Compiègne UTC-Ecole Supérieure de Chimie Organique et Minérale ESCOM

One novel nucleoside analogue having a hex-5-enyl group and an allyl group in the 5'-C and 3-N position was synthesized regioand diastereoselectively from D-glucose in twelve *** order to reach a particular conformation of nucleosides the nucleoside formation of restricted cyclonucleoside analogues was studied via Ring-Closing Metathesis.

关键词： nucleoside restrictedconformation metathesis

NTR/NRX Define a New Thioredoxin System in the Nucleus of Arabidopsis thaliana Cells

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Molecular Plant 2014年第1期7卷 30-44页

作者： Corinne Marchal Valerie Delorme-Hinoux Laetitia Bariat Wafi Siala christophe Belin Julio Saez-Vasquez christophe Riondet Jean-Philippe Reichheld Universite Perpignan Via Domitia CNRS Laboratoire Genome et Developpement des Plantes UMR 5096 58 Avenue Paul Alduy-Bat T F-66860 Perpignan France Pharmacologie cellulaire et moleculaire Louvain Drug Research Institute Universite catholique de Louvain Brussels Belgium

Thioredoxins （TRX） are key components of cellular redox balance, regulating many target proteins through thiol/disulfide exchange reactions. In higher plants, TRX constitute a complex multigenic family whose members have been found in almost all cellular compartments. Although chloroplastic and cytosolic TRX systems have been largely studied, the presence of a nuclear TRX system has been elusive for a long time. Nucleoredoxins （NRX） are potential nuclear TRX found in most eukaryotic organisms. In contrast to mammals, which harbor a unique NRX, angiosperms gen- erally possess multiple NRX organized in three subfamilies. Here, we show thatArabidopsis thaliana has two NRXgenes （AtNRX1 and AtNRX2）, respectively, belonging to subgroups I and III. While NRX1 harbors typical TRX active sites （WCG/ PPC）, NRX2 has atypical active sites （WCRPC and WCPPF）. Nevertheless, both NRXl and NRX2 have disulfide reduction capacities, although NRX1 alone can be reduced by the thioredoxin reductase NTRA. We also show that both NRX1 and NRX2 have a dual nuclear/cytosolic localization. Interestingly, we found that NTRA, previously identified as a cytosolic protein, is also partially localized in the nucleus, suggesting that a complete TRX system is functional in the nucleus. We show that NRX1 is mainly found as a dimer in vivo. nrxl and nrx2 knockout mutant plants exhibit no phenotypic perturbations under standard growth conditions. However, the nrxl mutant shows a reduced pollen fertility phenotype, suggesting a specific role of NRX1 at the haploid phase.

关键词： thioredoxin nucleoredoxin nucleus Arabidopsis.

Thermo-Mechanical Calculation of Printed Circuit Heat Exchanger Using Homogenization

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Journal of Thermal Science 2022年第6期31卷 2309-2328页

作者： GARNIER christophe VINCENT Sébastien LAMAGNERE Pierre LEJEAIL Yves CACHON Lionel CEA DESIRESNENuclear Technology DepartmentCadarache F-13108 Saint-Paul-Lez-DuranceFrance

The Finite-Element Method(FEM) is mainly used to design Compact Heat Exchanger structures. However, the narrow channel structures require fine mesh to accurately compute stress and strain. Combined with the dimensions of the overall component, this leads to an excessively large numerical model and therefore long computing time. This is especially true for transient thermal analyses, which require taking into account the full geometry. It is therefore interesting to reduce the size of the mesh. Periodic homogenization is an efficient method for achieving this goal. It can be applied to the core of the structure when periodic patterns(identified on basis of the arrangement of the channels) exist. A method based on this technique, with some improvements, is proposed in this paper for thermal loading without internal pressure. In addition to the Equivalent Homogenous Medium(EHM) replacing the periodic patterns, some explicit channels are interposed between the EHM and the cover plates. This has two advantages. The first is to smooth the transition of stiffness between the cover plates and the homogenized medium. The second one is to be able to directly compute stress and strain on the most critical channels located in this area. This paper assesses the method’s effectiveness for thermal loadings in order to conduct thermal stress analyses. First, the equivalent elastic constants of the EHM are obtained with a numerical Finite Elements Method. Then, two 2D cases using EHM are compared against a 2D explicit model(i.e. explicit geometry for the core channels). These cases are chosen to validate the EHM itself and its effectiveness for a real section of the heat exchanger. Results show very good agreement with a relative difference lower than 1%. In addition, the sensitivity to the number of layers added between the EHM and the cover plates is analysed. It is recommended interposing at least two layers of patterns to obtain converged results for the considered configuration

关键词： compact heat exchanger thermal stress finite element method homogenization

The promises and challenges of research on plant-insect-microbe interactions

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Insect Science 2017年第6期24卷 904-909页

作者： Jean-christophe Simon Arjen Biere Akiko Sugio UMR 1349 Institut de Genetique Environnement et Protection des Plantes INRA Agrocampus Ouest Universite Rennes 1 Domaine de la Motte Le Rheu Cedex France Department of Terrestrial Ecology Netherlands Institute of Ecology NIOO-KNA W Wageningen the Netherlands

Ecological interactions are of paramount importance for the functioning and health of ecosystems. Phytophagous insects are part of complex ecological networks involving abiotic factors, host plants, natural enemies, and benefi- cial organisms （McLean et al., 2016）. Insects and plants are also associated durably or transitorily with a wealth of microbes including pathogens, commensals and beneficial partners from a vast array of microbial taxa （Sugio et al., 2015）. In recent years, evidence has accumulated that microbes directly or indirectly influence plant-insect interactions at individual, population and community levels.

关键词： SYMBIONTS FUNGI

Circulating tumor cell isolation:the assets of filtration methods with polycarbonate track-etched filters

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Chinese Journal of Cancer Research 2015年第5期27卷 479-487页

作者： Claire Dolfus Nicolas Piton Emmanuel Toure Jean-christophe Sabourin Department of Pathology Rouen University Hospital Inserm U1079 Institute for Biomedical Research and InnovationUniversity of Rouen

Circulating tumor cells （CTCs） arise from primary or secondary tumors and enter the bloodstream by active or passive intravasation. Given the low number of CTCs, enrichment is necessary for detection. Filtration methods are based on selection of CTCs by size using a filter with 6.5 to 8 pm pores. After coloration, collected CTCs are evaluated according to morphological criteria. Immunophenotyping and fluorescence in situ hybridization techniques may be used. Selected CTCs can also be cultivated in vitro to provide more material. Analysis of genomic mutations is difficult because it requires adapted techniques due to limited DNA materials. Filtration-selected CTCs have shown prognostic value in many studies but multicentric validating trials are mandatory to strengthen this assessment. Other clinical applications are promising such as follow-up, therapy response prediction and diagnosis. Microfluidic emerging systems could optimize filtration-selected CTCs by increasing selection accuracy.

关键词： Circulating tumor ceils (CTCs) biological markers filtration

Application of an Artificial Neural Network Method for the Prediction of the Tube-Side Fouling Resistance in a Shell-And-Tube Heat Exchanger

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Fluid Dynamics & Materials Processing 2022年第5期18卷 1511-1519页

作者： Rania Jradi christophe Marvillet Mohamed-Razak Jeday Research Laboratory“Process EnergyEnvironment&Electrical Systems”National Engineering School of GabesGabes6029Tunisia CMGPCE Laboratory French Institute of Refrigeration(IFFI)National Conservatory of Arts and Crafts(CNAM)Paris75141France

The accumulation of undesirable deposits on the heat exchange surface represents a critical issue in industrial heat *** experimental measurements of the fouling is relatively difficult and,often,this method does not lead to precise *** overcome these problems,in the present study,a new approach based on an Artificial Neural Network(ANN)is used to predict the fouling resistance as a function of specific measurable variables in the phosphoric acid concentration *** include:the phosphoric acid inlet and outlet temperatures,the steam temperature,the phosphoric acid density,the phosphoric acid volume flow rate circulating in the *** statistical accuracy indices are employed simultaneously to justify the interrelation between these independent variables and the fouling resistance and to select the best training algorithm allowing the determination of the optimal number of hidden *** particular,the BFGS quasi-Newton back-propagation approach is found to be the most performing of the considered training ***,the best topology ANN for the shell and tube heat exchanger is obtained with a network consisting of one hidden layer with 13 neurons using a tangent sigmoid transfer function for the hidden and output *** model predicts the experimental values of the fouling resistance with AARD%=0.065,MSE=2.168×10^(−11),RMSE=4.656×10^(−6)and r^(2)=0.994.

关键词： Artificial neural network fouling resistance phosphoric acid concentration process shell-and-tube heat exchanger

Development and Application of a Reduced Order Model for the Control of Self-Sustained Instabilities in Cavity Flows

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Communications in Computational Physics 2013年第6期14卷 186-218页

作者： Kaushik Kumar Nagarajan Laurent Cordier christophe Airiau National Aerospace Laboratories Bengaluru560017India PPRIME Institute CEAT 43 route de l’aerodrome86000 PoitiersFrance Universite de Toulouse/INPT UPS/IMFT(Institut de M´ecanique des Fluides de Toulouse)/Allee Camille SoulaF-31400 ToulouseFrance

Flow around a cavity is characterized by a self-sustained mechanism in which the shear layer impinges on the downstream edge of the cavity resulting in a feedback *** Numerical Simulations of the flow at low Reynolds number has been carried out to get pressure and velocity fluctuations,for the case of un-actuated and multi frequency actuation.A Reduced Order Model for the isentropic compressible equations based on the method of Proper Orthogonal Decomposition has been *** model has been extended to include the effect of *** Reduced Order dynamical system shows a divergence in time integration.A method of calibration based on the minimization of a linear functional of error,to the sensitivity of the modes,is *** calibrated low order model is used to design a feedback control of cavity flows based on an observer *** the experimental implementation of the controller,a state estimate based on the observed pressure measurements is obtained through a linear stochastic *** the obtained control is introduced into the Direct Numerical Simulation to obtain a decrease in spectra of the cavity acoustic mode.

关键词： Reduced order modelling proper orthogonal decomposition cavity flows feedback control

A constitutive model for granular materials considering grain breakage

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Science China(Technological Sciences) 2011年第8期54卷 2188-2196页

作者： HU Wei YIN ZhenYu DANO christophe HICHER Pierre-Yves State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Chengdu 610059 China Center for Marine Geotechnics Research Department of Civil Engineering Shanghai Jiao Tong University Shanghai 200240 China Research Institute in Civil and Mechanical Engineering UMR CNRS 6183 Ecole Centrale de Nantes 44321 Nantes France

A particle breakage has a significant impact on the mechanical behavior of granular materials. In this paper, we present an elasto-plastic model with two yield surfaces to which the influence of particle breakage has been introduced. The main feature of this model is to incorporate the change in the critical state line (CSL) consequent to the grain breakage induced by isotropic and deviatoric stresses during loading. For this purpose we propose a breakage function which connects the evolution of the CSL to the energy consumed. Results from earlier studies on drained and undrained compression and extension triaxial tests were used to calibrate and validate the model. Comparison between earlier results and our simulations indicates that the model can reproduce with good accuracy the mechanical behavior of crushable granular materials and predict the evolution of the grain size distribution during loading.

关键词： granular materials grain breakage elasto-plasticity critical state grain size distribution

Topp-Leone Odd Fréchet Generated Family of Distributions with Applications to COVID-19 Data Sets

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Computer Modeling in Engineering & Sciences 2020年第10期125卷 437-458页

作者： Sanaa Al-Marzouki Farrukh Jamal christophe Chesneau Mohammed Elgarhy Statistics Department Faculty of ScienceKing AbdulAziz UniversityJeddah21551Saudi Arabia Department of Statistics Govt.S.A Postgraduate College Dera Nawab SahibBahawalpur63100Pakistan Universitéde Caen Normandie LMNOCampus IIScience 3Caen14032France Valley High Institute for Management Finance and Information Systems Obour11828Egypt

Recent studies have pointed out the potential of the odd Fréchet family(or class)of continuous distributions in fitting data of all *** this article,we propose an extension of this family through the so-called“Topp-Leone strategy”,aiming to improve its overall flexibility by adding a shape *** main objective is to offer original distributions with modifiable properties,from which adaptive and pliant statistical models can be *** the new family,these aspects are illustrated by the means of comprehensive mathematical and numerical *** particular,we emphasize a special distribution with three parameters based on the exponential *** related model is shown to be skillful to the fitting of various lifetime data,more or less *** all the possible applications,we consider two data sets of current interest,linked to the COVID-19 *** concern daily cases confirmed and recovered in Pakistan from March 24 to April 28,*** a result of our analyzes,the proposed model has the best fitting results in comparison to serious challengers,including the former odd Fréchet model.

关键词： General family of distributions asymmetric distributions probabilistic properties parametric estimation confidence intervals COVID-19 pandemic data analysis

Multi-dimensional morphology of hydride diffusion layer and associated sequential twinning in commercial pure titanium

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Journal of Materials Science & Technology 2022年第8期103卷 105-112页

作者： Qian Wang Shun Xu Yajun Zhao Jean-Sébastien Lecomte christophe Schuman Laboratoire d’Etude des Microstructures et de Mécanique des Matériaux(LEM3) Universitéde Lorraine CNRSArts et Métiers ParisTechMetz57073France Laboratory of Excellence on Design of Alloy Metals for low-mAss Structures(DAMAS) University of Lorraine57073France School of Iron and Steel Soochow UniversitySuzhou 215021China School of Materials Science and Engineering Dalian Jiaotong UniversityDalian 116021China

The dominant hydride precipitates have been well demonstrated to follow two types of orientation relationships(ORs)with Ti matrix:OR1 with{0001}//{001},//and OR2 with{0001}//{111},//.Within the grains with special orientations,the complicated interactions of different hydride variants inside Ti-hydride diffusion layer are characterized in this *** OR1 hydride layer,the orientations of{1010}plane parallel to the sample surface and a-axis parallel to the normal direction prefer multiple OR1 *** orientations favorable for OR2 hydride layer are:{1013}plane parallel to sample surface corresponding to the layer with one OR2 variant dominated and c-axis parallel to the surface normal with multiple OR2 variant layer ***,{1012}extension twins and{1122}contraction twins are activated to accommodate the OR2 hydride-induced surface expansion and local misfit *** stimulation of these two twins is also orientation-dependent:{1012}and{1122}twins are observed in the grains with c-axis parallel to and deviated from the surface normal,*** further variant selection for each twin mode is performed through shear accommodation of hydride-twin pairs.

关键词： Titanium Hydride Cross section Twin Variant selection