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npj computational Materials 2021年第1期7卷 1474-1480页

作者： Iaroslav Gaponenko Loïc Musy Neus Domingo nicolas Stucki Albert Verdaguer Nazanin Bassiri-Gharb Patrycja Paruch Department of Quantum Matter Physics University of GenevaGenevaSwitzerland G.W.Woodruff School of Mechanical Engineering Georgia Institute of TechnologyAtlantaGAUSA catalan Institute of Nanoscience and Nanotechnology(IcN2) CSIC and BISTCampus UABBarcelonaSpain University of Applied Sciences and Arts Western Switzerland(HES-SO/HEPIA) GenevaSwitzerland Institut de ciència de Materials de Barcelona(IcMAB) CSICCampus UABBarcelonaSpain School of Materials Science and Engineering Georgia Institute of TechnologyAtlantaGAUSA

Electrochemical phenomena in ferroelectrics are of particular interest for catalysis and sensing applications,with recent studies highlighting the combined role of the ferroelectric polarisation,applied surface voltage and overall switching history.Here,we present a systematic Kelvin probe microscopy study of the effect of relative humidity and polarisation switching history on the surface charge dissipation in ferroelectric Pb(Zr_(0.2)Ti_(0.8))O_(3)thin films.We analyse the interaction of surface charges with ferroelectric domains through the framework of physically constrained unsupervised machine learning matrix factorisation,Dictionary Learning,and reveal a complex interplay of voltage-mediated physical processes underlying the observed signal decays.Additional insight into the observed behaviours is given by a Fitzhugh–Nagumo reaction–diffusion model,highlighting the lateral spread and charge passivation process contributors within the Dictionary Learning analysis.

关键词： ferroelectric charge film

Plant functional and phylogenetic turnover correlate with climate and land use in the Western Swiss Alps

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Journal of Plant Ecology 2014年第5期7卷 439-450页

作者： charlotte Ndiribe Loïc Pellissier Anne Dubuis Pascal Vittoz nicolas Salamin Antoine Guisan Department of Ecology and Evolution University of LausanneBiophore BuildingUnil-SorgeVaudLausanne CH-1015Switzerland Swiss Institute of Bioinformatics GenopodeLausanne CH-1015Switzerland The Arctic Research centre Department of BioscienceAarhus UniversityAarhusDenmark Institute of Earth Surface Dynamics GeopolisUniversity of LausanneLausanne CH-1015Switzerland

Aims Understanding the relative importance of historical and environ-mental processes in the structure and composition of communities is one of the longest quests in ecological research.Increasingly,researchers are relying on the functional and phylogeneticβ-diversity of natural communities to provide concise explanations on the mechanistic basis of community assembly and the drivers of trait variation among species.The present study investigated how plant functional and phylogeneticβ-diversity change along key environmental and spatial gradients in the Western Swiss Alps.Methods Using the quadratic diversity measure based on six functional traits-specific leaf area,leaf dry matter content,plant height,leaf carbon content,leaf nitrogen content and leaf carbon to nitrogen content alongside a species-resolved phylogenetic tree-we relate variations in climate,spatial geographic,land use and soil gradients to plant functional and phylogenetic turnover in mountain commu-nities of the Western Swiss Alps.Important Findings Our study highlights two main points.First,climate and land-use factors play an important role in mountain plant community turnover.Second,the overlap between plant functional and phy-logenetic turnover along these gradients correlates with the low phylogenetic signal in traits,suggesting that in mountain land-scapes,trait lability is likely an important factor in driving plant community assembly.Overall,we demonstrate the importance of climate and land-use factors in plant functional and phyloge-netic community turnover and provide valuable complementary insights into understanding patterns ofβ-diversity along several ecological gradients.

关键词： ecological gradients functional and phylogeneticβ-diversity plant community turnover Rao’s quadratic entropy index(Q) Western Swiss Alps

Inhibition of glucuronidation in pancreatic cancer improves gemcitabine anticancer activity

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cancer communications 2022年第11期42卷 1212-1216页

作者： nicolas Alejandro Fraunhoffer Analía Meilerman Abuelafia Brice chanez Martin Bigonnet Odile Gayet Julie Roques Eduardo chuluyan Nelson Dusetti Juan Iovanna cancer Research center of Marseille InsermPaoli-Calmettes InstitutAix-Marseille UniversityScientific and Technological Park of LuminyMarseille 13288France Buenos Aires University Center for Pharmacological and Botanical StudiesFaculty of MedicineNational Council for Scientific and Technical ResearchBuenos AiresC1121ABGArgentina Buenos Aires University Faculty of MedicineDepartment of MicrobiologyParasitology and ImmunologyBuenos Aires C1121ABGArgentina Predicting Med Scientific and Technological Park of LuminyMarseille 13288France

Dear Editor,Pancreatic ductal adenocarcinoma(PDAc)treatment is focused on two regimens.The polychemotherapy,FOLFIRINOX(folinic acid,fluorouracil,irinotecan,oxali-platin),is used in patients with good health conditions[1],while gemcitabine,as monotherapy,in patients with poor health conditions[2–4].Gemcitabine resistance-associated pathways have been targeted to sensitize cancer cells,but the results were disappointing.Using a transcrip-tomic bioinformatics analysis combined with biological validation,we showed that glucuronidation was associ-ated with the gemcitabine resistance in PDAc,and its inhibition could switch tumors from resistant to sensitive.

关键词： gemcitabine cancer chemotherapy

Life Strategy Traits of the Liana Sericostachys scandens Spreading in the Montane Forests in the Kahuzi-Biega National Park (DR congo)

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Journal of Mountain Science 2012年第5期9卷 665-675页

作者： Masumbuko Ndabaga céphas Herpigny Basile Barbier nicolas Habiyaremye Muhashy Franois Lejoly Jean Meerts Pierre Université Officielle de Bukavu PoBox 570 Bukavu DR Congo Laboratoire d'Ecologie Végétale et Biogéochimie CP 244 Université Libre de Bruxelles Av FD Roosevelt 50 B-1050 Bruxelles Belgium Botany and computational Plant Architecture IRD - Marie Curie. 34398 Montpellier cedex 5 France Institut Royal des Sciences Naturelles de Belgique Rue Vautier 29 1000 Bruxelles Belgium Herbarium de l'Université Libre de Bruxelles 50 Avenue F. Roosevelt - CP 169 B-1050 Bruxelles Belgium

Sericostachys scandens is a monocarpic and heliophilous liana, native in tropical African forests. In the montane forests of the Kahuzi-Biega National Park (KBNP) (East of DR congo), it has been expanding very strongly for a decade, and is currently considered as having negative impacts on biodiversity conservation. In this paper, we test if S. scandens differs from three co-occurring, native, non spreading lianas (Gouania longispicata, Tacazzea apiculata and Adenia bequaertii) for functional traits which might influence plant expansion. For leaf traits (SLA, dry matter content, nitrogen concentration), S. scandens did not show extreme values compared to those of the three other lianas. In contrast, S. scandens had much higher biomass allocation to sexual reproduction. It also differs from the three other lianas for its reproductive strategy that combines both vegetative propagation and sexual reproduction, and propagule dispersal by wind. Moreover, S. scandens has larger leaves and a greater number of lateral branches per unit stem length. It is argued that the particular combination of functional traits exhibited by S.scandens may in part explain its propensity to behave as an opportunistic weed in the disturbed areas in the montane forests of Kahuzi-Biega.

关键词：刚果民主共和国山地森林国家公园叶性状传播藤本植物生活有性繁殖

Transversal Instability for the Thermodiffusive Reaction-Diffusion System

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chinese Annals of Mathematics,Series B 2015年第5期36卷 871-882页

作者： Michal KOWALcZYK Benoit PERTHAME nicolas VAUcHELET Departamento de Ingenieria Matematica and centro de Modelamiento Matem'atico(UMI cNRS 2807) Universidad de Chile Sorbonne Universités UPMC Univ Paris 06UMR 7598Laboratoire Jacques-Louis LionsF-75005ParisFrance cNRS UMR 7598Laboratoire Jacques-Louis LionsF-75005ParisFrance INRIA-Paris-Rocquencourt EPC MAMBADomaine de VoluceauBP10578153 Le Chesnay CedexFrance

The propagation of unstable interfaces is at the origin of remarkable patterns that are observed in various areas of science as chemical reactions, phase transitions, and growth of bacterial colonies. Since a scalar equation generates usually stable waves, the simplest mathematical description relies on two-by-two reaction-diffusion systems. The authors' interest is the extension of the Fisher/KPP equation to a two-species reaction which represents reactant concentration and temperature when used for flame propagation,and bacterial population and nutrient concentration when used in biology.The authors study circumstances in which instabilities can occur and in particular the effect of dimension. It is observed numerically that spherical waves can be unstable depending on the coefficients. A simpler mathematical framework is to study transversal instability, which means a one-dimensional wave propagating in two space dimensions.Then, explicit analytical formulas give explicitely the range of paramaters for instability.

关键词： Traveling waves Stability analysis Reaction-diffusion equation Thermodiffusive system

Optimizing stem cells for cardiac repair:current status and new frontiers in regenerative cardiology

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World Journal of Stem cells 2017年第1期9卷 9-25页

作者： Shant Der Sarkissian Thierry Lévesque nicolas Noiseux Department of Surgery Faculté de Médecine Université de MontréalMontrealQC H3C 3J7Canada Facultéde Médecine Universitéde MontréalMontrealQC H3C 3J7Canada

cell therapy has the potential to improve healing of ischemic heart, repopulate injured myocardium and restore cardiac function. The tremendous hope and potential of stem cell therapy is well understood, yet recent trials involving cell therapy for cardiovascular diseases have yielded mixed results with inconsistent data thereby readdressing controversies and unresolved questions regarding stem cell efficacy for ischemic cardiac disease treatment. These controversies are believed to arise by the lack of uniformity of the clinical trial methodologies, uncertainty regarding the underlying reparative mechanisms of stem cells, questions concerning the most appropriate cell population to use, the proper delivery method and timing in relation to the moment of infarction, as well as the poor stem cell survival and engraftment especially in a diseased microenvironment which is collectively acknowledged as a major hindrance to any form of cell therapy. Indeed, the microenvironment of the failing heart exhibits pathological hypoxic, oxidative and inflammatory stressors impairing the survival of transplanted cells. Therefore, in order to observe any significant therapeutic benefit there is a need to increase resilience of stem cells to death in the transplant microenvironment while preserving or better yet improving their reparative functionality. Although stem cell differentiation into cardiomyocytes has been observed in some instance, the prevailing reparative benefits are afforded through paracrine mechanisms that promote angiogenesis, cell survival, transdifferentiate host cells and modulate immune responses. Therefore, to maximize their reparative functionality, ex vivo manipulation of stem cells through physical, genetic and pharmacological means have shown promise to enable cells to thrive in the postischemic transplant microenvironment. In the present work, we will overview the current status of stem cell therapy for ischemic heart disease, discuss the most recurring cell populations employed, the mechanisms by whic

关键词： Stem cell Regenerative medicine cellular cardiomyoplasty Preconditioning Myocardial infarction Heart failure Viability Paracrine activity Transplantation Pharmaco-optimizer

电池储能系统的特性、建模、SOc估计及与微电网系统集成

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电池储能系统的特性、建模、SOC估计及与微电网系统集成

作者： Bamamou nicolas 北京交通大学

学位级别：硕士

追求现代电网,让消费者能够参与环境友好型能源,是许多电力设施规划者和研究者关注的中心。这种兴趣促进了当代电网系统对可再生能源(REs)的高度接受,这种新的电网组织方式被称为微电网(MG)。然而,风能和太阳能光伏等间歇性能源在现代... 详细信息

追求现代电网,让消费者能够参与环境友好型能源,是许多电力设施规划者和研究者关注的中心。这种兴趣促进了当代电网系统对可再生能源(REs)的高度接受,这种新的电网组织方式被称为微电网(MG)。然而,风能和太阳能光伏等间歇性能源在现代微电网(MG)中的高渗透率导致了一些关于电网稳定性、能源管理、辅助服务和市场波动的重大挑战。应对这些挑战需要具有短响应时间的高效储能系统,如电池储能系统(BESS),它可以通过向电网注入瞬时电力和支持传统发电系统来提供频率和电压支持。在本论文工作中,基于子系统模型方法,有效地设计了一个由BESS、光伏系统、柴油发电机和强电网组成的交流微电网。每个子系统的性能分析和验证都是以BESS的系统频率、电压和惯性响应为重点进行的。首先,开发了一个二阶电阻-电容等效电路电池模型,称为增强型自校正模型(ESc),在各种工作条件下进行直观和准确的模拟。该模型包括等效串联电阻周围的极化电压降。它还包括由锂通过电解质迁移引起的扩散过程,以及描述由于对应于给定输入电流的开路电压的偏差而产生的动态和瞬时滞后。同时,为了提取电池开路电压(OcV)与So c和温度的关系曲线,进行了电池单元的特征分析。在对ESc电池模型进行关键的验证过程后,它就成为使用一种叫做扩展卡尔曼滤波(EKF)的基于高斯滤波的方法进行电池状态估计的关键条件。该估算器使用顺序概率推理的一个特定案例,根据从电池循环器收集的测量电压和从电调模型获得的预测电压之间的输出误差,动态地改变状态值。在光伏方面,基于数据表-参数识别方法提出了一个等效电路电池模型。然后,最大功率点跟踪技术的增量电导率算法被连接到升压转换器,以便为所需的直流链路电压产生转换器的门控占空比。为了验证光伏系统的准确性和效率,在光伏阵列和其电力调节装置(PcU)的直流链路之间进行了系统性能分析。在交流层面,设计了一个由同步机和励磁单元组成的柴油发电机,并由其调速器侧的自动电压调节器(AVR)进行有效控制,还进行了稳定性分析,以验证网络干扰后系统的稳健性。此外,通过增加发电量扩大了同步发电机和励磁单元的组合,然后与输电线路连接,形成一个强大的电网。最后,由电网支持转换器、非隔离双向直流转换器和基于三端双向开关的共同耦合点(Pcc)类型组成的电力对话和控制系统作为接口设备,用于整合所设计的分布式能源资源(DER)。此外,估计的充电状态(So c)被设定为BESS充电器层面的智能控制技术的约束条件,以实现安全的充电和放电过程,考虑到Ac-MG与公用电网之间的需求和供应。此外,光伏系统和BESS的虚拟惯性仿真技术在它们各自的PcU中进行,以改善它们在交流-MG中的紧急情况下的惯性反应。MATLAB Simulink作为一个建模和仿真环境。

关键词：电池储能系统(BESS) 等效电路模型(EcM) 电荷状态(Soc)估计扩展卡尔曼滤波(EKF) 微电网(MG) 电力调节系统(PcS)

comparative Genomic Study of the Thioredoxin Family in Photosynthetic Organisms with Emphasis on Populus trichocarpa

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Molecular Plant 2009年第2期2卷 308-322页

作者： Kamel chibani Gunnar Wingsle Jean-Pierre Jacquot Eric Gelhaye nicolas Rouhier UMR 1136 Nancy University-INRA Interactions Arbres Microorganismes IFR 110 GEEF Faculte des Sciences BP 239 54506 Vandoeuvre-les-Nancy Cedex France Department of Forest Genetics and Plant Physiology Swedish University of Agricultural Sciences Umea Plant Science Centre 90183 Umea Sweden

The recent genome sequencing of Populus trichocarpa and Vitis vinifera, two models of woody plants, of Sorghum bicolor, a model of monocot using c4 metabolism, and of the moss Physcomitrella patens, together with the availability of photosynthetic organism genomes allows performance of a comparative genomic study with organisms having different ways of life, reproduction modes, biological traits, and physiologies. Thioredoxins （Trxs） are small ubiq- uitous proteins involved in the reduction of disulfide bridges in a variety of target enzymes present in all sub-cellular compartments and involved in many biochemical reactions. The genes coding for these enzymes have been identified in these newly sequenced genomes and annotated. The gene content, organization and distribution were compared to other photosynthetic organisms, leading to a refined classification. This analysis revealed that higher plants and bryo- phytes have a more complex family compared to algae and cyanobacteria and to non-photosynthetic organisms, since poplar exhibits 49 genes coding for typical and atypical thioredoxins and thioredoxin reductases, namely one-third more than monocots such as Oryza sativa and S. bicolor. The higher number of Trxs in poplar is partially explained by gene duplication in the Trx m, h, and nucleoredoxin classes. Particular attention was paid to poplar genes with emphasis on Trx-like classes called clot, thioredoxin-like, thioredoxins of the lilium type and nucleoredoxins, which were not described in depth in previous genomic studies.

关键词： Genomic oxidoreductase poplar redox regulation thioredoxins.

Preoperative albumin level is a marker of alveolar echinococcosis recurrence after hepatectomy

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World Journal of Gastroenterology 2017年第5期23卷 853-858页

作者： Gaetan-Romain Joliat Ismail Labgaa nicolas Demartines Nermin Halkic Department of Visceral Surgery University Hospital CHUV1011 LausanneSwitzerland

AIM To identify a preoperative blood marker predictive of alveolar echinococcosis(AE) recurrence after hepatectomy.METHODS All consecutive patients who underwent operation for liver AE at the Lausanne University Hospital(cHUV) between January 1992 and December 2015 were included in this retrospective study. Preoperative laboratory values of leukocytes, mean corpuscular volume(McV), red blood cell distribution width(RDW), thrombocytes, c-reactive protein(cRP) and albumin were collected and analyzed. Univariate and multivariate cox regression analyses were performed to determine the risk factors for AE recurrence after liver resection. A receiver operating characteristic(ROc) curve was used to define the best discrimination threshold of the blood marker. Moreover, recurrencefree survival curves were calculated using the KaplanMeier method.RESULTS The cohort included 68 adult patients(37 females) with median age of 61 years [interquartile range(IQR): 46-71]. Eight of the patients(12%) presented a recurrence over a median follow-up time of 76 mo(IQR: 34-128). Median time to recurrence was 10 mo(IQR: 6-11). Median preoperative leukocyte, McV, RDW,thrombocyte and cRP levels were similar between recurrent and non-recurrent cases. Median preoperative albumin level was 43 g/L(IQR: 41-45) for nonrecurrent cases and 36 g/L(IQR: 33-42) for recurrent cases(P = 0.005). The area under the ROc curve for preoperative albumin level to predict recurrence was 0.840(95%cI: 0.642-1, P = 0.002). The cutoff albumin level value was 37.5 g/L for sensitivity of 94.5% and specificity of 75%. In multivariate analysis, preoperative albumin and surgical resection margins were independent predictors of AE recurrence(HR = 0.099, P = 0.007 and HR = 0.182, P = 0.045 respectively).cONcLUSION Low preoperative albumin level was associated with AE recurrence in the present cohort. Thus, preoperative albumin may be a useful biomarker to guide follow-up.

关键词：肝外科牙槽的包虫病白朊预兆的标记复发