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Detecting polygenic selection in marine populations by combining population genomics and quantitative genetics approaches

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Current Zoology 2016年第6期62卷 603-616页

作者： pierre-Alexandre GAGNAIRE Oscar E. GAGGIOTTI Universite Montpellier 2 Place Eugene Bataillon 34095 Montpellier Cedex 5 France ISEM - CNRS UMR 5554 SMEL 2 rue des Chantiers Sete 34200 France Scottish Oceans Institute University of St Andrews East Sands St Andrews KY16 9LB UK

Highly fecund marine species with dispersive life-history stages often display large population sizes and wide geographic distribution ranges. Consequently, they are expected to experience reduced genetic drift, efficient selection fueled by frequent adaptive mutations, and high migration loads. This has important consequences for understanding how local adaptation proceeds in the sea. A key issue in this regard, relates to the genetic architecture underlying fitness traits. Theory predicts that adaptation may involve many genes but with a high variance in effect size. Therefore, the effect of selection on allele frequencies may be substantial for the largest effect size loci, but insignificant for small effect genes. In such a context, the performance of population genomic methods to unravel the genetic basis of adaptation depends on the fraction of adaptive genetic variance explained by the cumulative effect of outlier loci. Here, we address some methodological challenges associated with the detection of local adaptation using molecular approaches. We provide an overview of genome scan methods to detect selection, including those assuming complex demographic models that better describe spatial population structure. We then focus on quantitative genetics approaches that search for genotype-phenotype associations at different genomic scales, including genome-wide methods evaluating the cumulative effect of variants. We argue that the limited power of single locus tests can be alleviated by the use of polygenic scores to estimate the joint contribution of candidate variants to phenotypic variation.

关键词： local adaptation genome scans quantitative genetics genotype-phenotype association polygenic scores.

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Screening for hypertension-mediated organ damage and aetiology:still of value after 65 years of age?

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Journal of Geriatric Cardiology 2022年第11期19卷 791-801页

作者： Delphine Thiolliere Brahim Harbaoui Claire Falandry Marc Bonnefoy Jean-Christophe Lega pierre Lantelme pierre-Yves Courand Fédération de cardiologie Hôpital de la Croix-Rousse et Hôpital Lyon SudHospices Civils de LyonLyonFrance Universitéde Lyon CREATISCNRS UMR5220INSERM U1044INSA-LyonUniversitéClaude Bernard LyonFrance Service Universitaire de Gériatrie Hôpital Lyon SudHospices Civils de LyonLyonFrance CarMeN UniversitéClaude Bernard Lyon 1OullinsFrance Service de médecine interne et pathologies vasculaires Groupe d’Etude Multidisciplinaires des Maladies Thrombotiques(GEMMAT)Hôpital Lyon SudHospices Civils de LyonLyonFrance Universitéde Lyon Equipe Evaluation et Modélisation des Effets ThérapeutiquesLaboratoire de Biologie et Biométrie EvolutiveCNRS UMR 5558UniversitéClaude BernardLyonFrance

BACKGROUND Secondary forms and hypertension-mediated organ damage(HMOD) may differ between younger and older hypertensive *** aim of the present study was to explore the specificity of HMOD and secondary forms in patients≥ 65 years in comparison to younger ones in a contemporary *** We analysed 938 patients recruited between 2004 and 2014(Cardiology department,Croix-Rousse Hospital,Lyon)who had at baseline HMOD and secondary forms screening among them 190 were≥ 65 *** The mean(2.1±0.8 vs.1.2±0.9,P 10 m/s was the most frequent HMOD in patients≥ 65 years(90.1%),while echocardiographic left ventricular hypertrophy was the most common in the younger patients(45.0%).Among ECG left ventricular indexes,only R wave in aVL lead was significantly more frequently observed in patients≥ 65 years(32.6%) than in younger ones(19.0%,P <0.001).The frequency of secondary hypertension was not significantly different between younger and older patients(respectively;30.5% vs.27.8%,P=0.487).The most frequent aetiology was primary aldosteronism regardless of age,followed by renovascular hypertension(6.3% vs.3.3%,P=0.038).Among older patients,3.2% were treated with adrenalectomy and 6.3% with percutaneous transluminal renal *** Extensive screening of HMOD in older patients may be questionable as nearly all patients had one;aetiology must however be explored as a third of older patients had a secondary form.

关键词： Extensive screening of HMOD in older patients may be questionable as nearly all patients had one aetiology must however be explored as a third of older patients had a secondary form

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Effects of Polypropylene Fibers on the Physical and Mechanical Properties of Recycled Aggregate Concrete

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Journal of Wuhan University of Technology(Materials Science) 2019年第6期34卷 1327-1344页

作者： pierre Matar Gérard-Philippe Zéhil Lebanese University Faculty of EngineeringBranch 2RoumiehLebanon Notre Dame University-Louaize Faculty of EngineeringZouk MosbehLebanon

The viability of using polypropylene fibers(PPF) in concrete was largely studied. Yet, few of the existing research studies investigated the effects of PPF on the properties of concrete containing recycled concrete aggregate(RCA). Mixes with different RCA replacement ratios and different PPF content were designed and tested. The test results showed that the addition of PPF did not change significantly the compressive strength and the density of the concrete, but slightly decreased its modulus of elasticity and Poisson’s ratio. The drop in the splitting tensile strength and the flexural strength due to RCA inclusions was to a large extent compensated by the PPF addition. The water absorption decreased and the percent voids increased with increased PPF addition. Correlations between the RCA content, the PPF content and the properties of concrete were studied. Useful regression models were proposed to predict the properties of concrete in relevant ranges of RCA and PPF content.

关键词： concrete recycled aggregate fiber reinforcement physical properties mechanical properties

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Penalty Algorithms in Hilbert Spaces

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Acta Mathematica Sinica,English Series 2007年第2期23卷 229-236页

作者： Jean pierre DUSSAULT Hai SHEN André BANDRAUK Département d'Informatique Faculté des Sciences.Université de Sherbrooke Viador inc Laboratoire de Chimie Théorique Faculté des Sciences Université de Sherbrooke

We analyze the classical penalty algorithm for nonlinear programming in Hilbert spaces and obtain global convergence results, as well as asymptotic superlinear convergence order. These convergence results generalize similar results obtained for finite-dimensional problems. Moreover, the nature of the algorithms allows us to solve the unconstrained subproblems in finite-dimensional spaces.

关键词： penalty methods infinite dimensional optimization

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Sedimentary facies and paleoenvironmental interpretation of a Holocene marsh in the Gironde Estuary in France

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Acta Oceanologica Sinica 2006年第6期25卷 52-62页

作者： WANG Jianhua MASSE Laurent TASTET Jean -pierre Department of Earth Sciences Sun Yat-sen （Zhongshan） University Guangzhou 510275 China Départment de Géologie et Océanographie Université Bordeaux I 33405 Talence cédèx France

The Monards Marsh is located on the northeastern bank of the Gironde Estuary in France. Lithological, sedimentolngical and mi- cropalacontological investigations were made on four cores to determine the evolution of Holocene sedimentary environments and processes in this area over the last 6 000 a. Three main lithological facies are distinguished from bottom to top：（ 1 ） grey laminated silty-sandy clay ; （2） homogeneous dark grey silty clay ; and （ 3 ） compact silty clay. About 26 benthic foraminifera species are identified and divided into six groups according to their ecological characteristics. In association with lithology, sedimentary structures and grainuiometry, the distribution of foraminifera group is used to define external slikke, internal slikke, external schorre, internal schorre, and continental marsh facies. Combined with 14C（AMS） dating, these data indicate four successive paleoenvironments in the Monards Marsh：（ 1 ） Holocene transgression resuited in the development of a basal schorre facies overlying fluvial deposits that transformed to slikke facies sedimentation; the transgression maximum occurred around 5 600 to 5 4430 a BP and was inferred to be associated with the last phase of the rapid Holocene sea-level rise; （2） post-trangressive maximum sedimentation resuited in a regressive sequence of deposits prograding towards the estuary, corresponding to the stahilisation of sea level after 5 4430 a BP; （3） a slight positive tendency in the sea level around 2 800 a BP recorded in the central part of the marsh; and （4） the wetland to a continental marsh environment. The sequential pattern for the evolution of wetlands in this estuarine area during the Holocene is fluvial facies - blackish schorre facies - slikke facies - blackish schorre facies - continental marsh facies. Characteristics of sedimentary facies distribution and evolution reveal that the development of Holocene salt marsh in this area was controlled by the sea-level change and tidal r

关键词： marsh sedimentation benthic foraminifera,^ 14C dating Holocene sea-level fluctuation paleoenvironment

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Conductance hysteresis and inelastic excitations at hydrogen decorated cerium atoms and clusters in a tunnel junction

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Nano Research 2016年第10期9卷 3171-3178页

作者： Rouzhaji Tuerhong Shawulienu Kezilebieke Bernard Barbara Jean-pierre Bucher Institut Universitaire de France Universite de Strasbourg 23 rue du Loess F-67034 Strasbourg France Institut Neel CNRS Universite Grenoble-Alpes F-38042 Grenoble France

Voltage-controlled conductance and switching induced by single molecules or atoms are ideally studied in scanning tunneling microscope （STM） tunnel junctions. While the objects under consideration are mostly used in their original form, little is known of the possibilities of in situ adjustments of their properties. Here, we evidence properties of a tunnel junction made of a Ce atom/cluster built by atomic manipulation on Au（111） at a temperature of 4.6 K in the presence of H2. The conductance through the object is characterized by a switching voltage corresponding to an opening or closing of an inelastic electron tunneling conductance channel at 50 mV for a Ce atom and 140 mV for a Ce cluster and by charging. We demonstrate that the electronic properties of an STM junction can be engineered in a simple way by in situ guiding of the H2 pinning at an atomic cluster.

关键词： conductance hysteresis inelastic electron tunelingspectroscopy (IETS) switching Ce clusters scanning tunneling microscope (STM)/scanning tunneling spectroscopy (STS)

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Materials property prediction for limited datasets enabled by feature selection and joint learning with MODNet

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npj Computational Materials 2021年第1期7卷 731-738页

作者： pierre-Paul De Breuck Geoffroy Hautier Gian-Marco Rignanese UCLouvain Institute of Condensed Matter and Nanosciences(IMCN)Louvain-la-NeuveBelgium Dartmouth College Thayer School of EngineeringHanoverNHUSA

In order to make accurate predictions of material properties,current machine-learning approaches generally require large amounts of data,which are often not available in *** this work,MODNet,an all-round framework,is presented which relies on a feedforward neural network,the selection of physically meaningful features,and when applicable,*** to being faster in terms of training time,this approach is shown to outperform current graph-network models on small *** particular,the vibrational entropy at 305 K of crystals is predicted with a mean absolute test error of 0.009 meV/K/atom(four times lower than previous studies).Furthermore,joint learning reduces the test error compared to single-target learning and enables the prediction of multiple properties at once,such as temperature ***,the selection algorithm highlights the most important features and thus helps to understand the underlying physics.

关键词： learning prediction property

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Two-phase flow distributors for fuel cell flow channels

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Particuology 2010年第6期8卷 582-587页

作者： Hsiaotao T.Bi pierre Sauriol Jürgen Stumper Clean Energy Research Centre and Department of Chemical and Biological Engineering University of British ColumbiaVancouverBCCanadaV6T 1Z4 Automotive Fuel Cell Corporation BurnabyBCCanadaV5J 5J8

All existing proton exchange membrane （PEM） fuel cell gas flow fields have been designed on the basis of single-phase gas flow distribution. The presence of liquid water in the flow causes non-uniform gas distribution, leading to poor cell performance. This paper demonstrates that a gas flow restrictor/distributor, as is commonly used in two-phase flow to stabilize multiphase transport lines and multiphase reactors, can improve the gas flow distribution by significantly reducing gas real-distribution caused by either non-uniform water formation in parallel flow channels or flow instability associated with negative-slope pressure drop characteristic of two-phase horizontal flow systems.

关键词： Gas distributor Gas-liquid two-phase flow Fuel cell flow field Pressure drop hysteresis Flow real-distribution

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On Triangular Lattice Boltzmann Schemes for Scalar Problems

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Communications in Computational Physics 2013年第3期13卷 649-670页

作者： Francois Dubois pierre Lallemand Conservatoire National des Arts et Metiers Department of MathematicsParisand Department of MathematicsUniversity Paris-SudBat.425F-91405 Orsay CedexFrance Centre National de la Recherche Scientifique ParisFrance

We propose to extend the d’Humi`eres version of the lattice Boltzmann scheme to triangular *** use Bravais lattices or more general lattices with the property that the degree of each internal vertex is supposed to be *** such meshes,it is possible to define the lattice Boltzmann scheme as a discrete particle method,without need of finite volume formulation or Delaunay-Voronoi hypothesis for the *** test this idea for the heat equation and perform an asymptotic analysis with the Taylor expansion method for two schemes named D2T4 and *** results show a convergence up to second order accuracy and set new questions concerning a possible super-convergence.

关键词： Laplacian operator heat equation d’Humi`eres scheme D2T4 D2T7

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Ring-opening Copolymerization of ε-Caprolactone and δ-Valerolactone Catalyzed by a 2,6-Bis(amino)phenol Zinc Complex

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Chinese Journal of Polymer Science 2020年第3期38卷 240-247,I0006页

作者： Qian Hu Su-Yun Jie pierre Braunstein Bo-Geng Li State Key Laboratory of Chemical Engineering College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310027China Universitéde Strasbourg CNRSCHIMIE UMR 7177Laboratoire de Chimie de Coordination67081 Strasbourg CedexFrance

In combination with methyllithium,a 2,6-bis(amino)phenol zinc complex 1 was used in the ring-opening polymerization ofδ-valerolactone in the absence or presence of benzyl alcohol and showed high efficiency,mainly producing cyclic and linear polyvalerolactones,*** the basis of homopolymerization,the ring-opening copolymerization ofε-caprolactone andδ-valerolactone was *** P(CL-co-VL)random copolymers,PCL-b-PVL and PVL-b-PCL diblock copolymers,were prepared by varying the feeding strategy(premixing or sequential feeding).The copolymer composition was adjusted by varying the feeding ratio of two *** structure and thermal properties of obtained polymers were characterized by GPC,1 H-NMR,13 C-NMR,MALDI-TOF mass spectroscopy,and DSC,respectively.

关键词： Zn complex Copolymerization Block copolymer Random copolymer

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