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Do endemic species always have a low competitive ability? A test for two Mediterranean plant species under controlled conditions

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Journal of Plant Ecology 2012年第3期5卷 305-312页

作者： Eric Imbert Sami Youssef David Carbonell Alex Baumel Institut des Sciences de l’Evolution CNRS 5554Universite Montpellier 2France Institut Mediterraneen d’Ecologie et de Paleoecologie UMR CNRS/IRD 6116Universite Aix MarseilleFrance

Aims Many observations concerning biological and ecological differentiation between narrow endemic and widespread congeneric plant species suggest that narrow endemic species are constrained to colonize marginal habitats because of a low tolerance to *** this topic being an important issue both for understanding evolutionary processes leading to endemism and for conservation purposes,few studies have been performed to compare competitive abilities between endemic and widespread ***,we present two independent experiments performed under controlled conditions using two different pairs of endemic and widespread congeneric species:Centaurea corymbosa/Centaurea maculosa and Arenaria provincialis/Arenaria serpyllifolia,both endemic species occurring in rocky calcareous *** Mature seeds of *** and *** were sown in pots containing ramets of the common grass,Brachypodium *** were sorted in three treatments according to grass cover(low,intermediate and high).A control treatment(without competition)was also ***,seedling survival and rosette growth were *** the comparisons between *** and ***,seeds from natural populations were first sown without a *** week after germination,healthy seedlings were transplanted in pots without Brachypodium seedling(control)or containing two Brachypodium seedlings(low competition)or four seedlings(high competition).We checked the number of capsules per individual,and we harvested the biomass after capsule *** Findings Despite differences in the protocol design,results are congruent,and in both cases,endemic species are highly affected by the presence of a competitor,as are the widespread species,although we did not detect any differences between species for response to *** results are discussed in relation to processes leading to endemism,suggesting that the specialist model is more likely for both the

关键词： endemism conservation biology Mediterranean area competitive response

Mechanisms of electrochemical magnesium(de)alloying of Mg-Sn and Mg-Pb polymorphs

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Journal of Magnesium and Alloys 2022年第6期10卷 1609-1616页

作者： Clément Pechberty Antoine Klein Bernard Fraisse Lorenzo Stievano Romain Berthelot ICGM CNRSUniv.MontpellierENSCMMontpellierFrance RS2E CNRSHub de l’EnergieAmiensFrance

Different polymorphs of Mg-Sn and Mg-Pb intermetallic compounds were prepared by high-energy mechanical alloying and then investigated as active material in magnesium batteries. Beside thermodynamically stable Mg_(2)Sn and Mg_(2)Pb crystallizing in the anti-fluorite structure, other polymorphs Mg_(~2)Sn and Mg_(~2)Pb were prepared by increasing the ball-milling time. The first dealloying process is almost complete only for the cubic polymorphs, then similar capacities are observed during the subsequent alloying and dealloying *** to operando X-ray diffraction, the electrochemical mechanism is revealed and shows that the cubic polymorphs Mg_(2)Sn and Mg_(2)Pb tend to preferentially form during the alloying whatever the pristine intermetallic. Weak traces of Mg_(~2)Sn and Mg_(~2)Pb are observed during the alloying, suggesting that these polymorphs act as a by-product and/or an intermediate phases of the electrochemical process. Finally, the compatibility of cubic Mg_(2)Sn and Mg_(2)Pb with Mg(TFSI)_(2)-based electrolyte is confirmed in full cell vs. a positive electrode based on the Chevrel phase Mo6S8, although limited performance is achieved. This fundamental work provides new insights in the behavior of alloy-type negative electrodes for magnesium-ion batteries.

关键词： Magnesium batteries Alloy electrode Mechanochemistry Operando X-ray diffraction

Changing assembly processes during a primary succession of plant communities on Mediterranean roadcuts

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Journal of Plant Ecology 2013年第1期6卷 19-28页

作者： Valerie Raevel Francxois Munoz Virginie Pons Alain Renaux Arnaud Martin John D.Thompson universite montpellier 2 and cnrs Centre d’Ecologie Fonctionnelle et EvolutiveUMR 51751919 route de Mende34293 Montpellier Cedex 5France universite´montpellier 2 botAnique et bioinforMatique de l’Architecture des PlantesTA A-51/PS234398 Montpellier Cedex 5France

Aims Studying plant ecological succession provides insights into the spatiotemporal processes underlying community assembly and is of primary importance for restoration *** investigate here colonization events and local community assembly over an original primary succession occurring on roadcuts after *** this,we addressed both the changes in species presence–absence(incidence data)to highlight pre-establishment filters and in species relative abundances to further assess the influence of local biotic *** We studied 43 limestone roadcuts in Mediterranean France,covering five age classes up to an age of 80 years,along with 13 natural cliffs as a reference,and we counted 14322 plant individuals on these *** applied a constrained nonsymmetric correspondence analysis of both the incidence(presence–absence)and abundance data to assess the variation of these data along the *** Findings Along the first 30 years,the initially abundant short-lived species declined both in terms of incidence and abundance and were replaced by longer lived herbaceous and woody *** first phase was characterized by species that are widespread in the surrounding scrublands and was comparable to an early secondary succession *** 30 years,there were continuing changes in incidence data with age,but no more significant change in species’*** second phase was marked by the late colonization of specialists that did not become *** colonization and establishment limitation was thereby apparent for specialist species,a slow convergence of community composition toward the situation of natural cliffs could be detected in the older stages of the *** findings convey insights into the natural dynamics of man-made outcrop plant communities and may be useful for the ecological management and restoration of such *** also illustrates the interest of comparing incidence and abundance data to i

关键词： primary succession roadcut colonization dynamics assembly rules Mediterranean environment non-symmetric correspondence analysis

Once upon a time biomass burning in the western Alps: Nesting effects of climate and local drivers on long-term subalpine fires

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Forest Ecosystems 2022年第2期9卷 257-266页

作者： Christopher Carcaillet Benjamin Boulley Frederique Carcaillet Univ Lyon Universite Claude Bernard Lyon 1CNRSENTPE(UMR LEHNA)F-69622VilleurbanneFrance Paris Sciences&Lettres University(PSL) Ecole Pratique des Hautes Etudes(EPHE)F-75014ParisFrance NaturCom Chair Universite de MontpellierF-34000MontpellierFrance MARBEC(universite de montpellier CNRSIfremerIRD)F-34000MontpellierFrance

Background:The present article questions the relative importance of local-and large-scale processes on the long-term dynamics of fire in the subalpine belt in the western *** study is based on soil charcoal dating and identification,several study sites in contrasting environmental conditions,and sampling of soil charcoal along the elevation gradient of each *** on local differences in biomass combustion,we hypothesize that local-scale or landscape-scale processes have driven the fire history,while combustion homogeneity supports the hypothesis of the importance of large-scale or macro-ecological processes,especially ***:Biomass burning during the Holocene resulted from the nesting effects of climate,land use,and altitude,but was little influenced by slope exposure(north versus south),soil(dryness,pH,depth),and *** mid-Holocene(6500–2700 cal BP)was an important period for climate-driven biomass burning in the subalpine ecosystems of the western Alps,while fires over the last 2500 years appear much more episodic,prompting us to speculate that human activity has played a vital role in their ***:Our working hypothesis that the strength of local drivers should offset the effects of regional climate is not *** homogeneity of the fire regime between sites thus underscores that climate was the main driver during the Holocene of the western ***-term subalpine fires are controlled by climate at the millennial *** conditions matter for little in determining variability at the century *** mid-Holocene was a chief period for climatic biomass burning in the subalpine zone,while fires during the late Holocene appear much more episodic,suggesting that social drivers has exercised key function on their control.

关键词： Biomass burning Subalpine forest Climate Landscape Pedoanthracology Radiocarbon dating Pyrogenic carbon

Mid-infrared Ⅲ-Ⅴ semiconductor lasers epitaxially grown on Si substrates

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Light(Science & Applications) 2022年第7期11卷 1366-1378页

作者： Eric Tournié Laura Monge Bartolome Marta Rio Calvo Zeineb Loghmari Daniel A.Díaz-Thomas Roland Teissier Alexei N.Baranov Laurent Cerutti Jean-Baptiste Rodriguez IES University of MontpellierCNRS34000 MontpellierFrance

There is currently much activity toward the integration of mid-infrared semiconductor lasers on Si substrates for developing a variety of smart,compact,sensors based on Si-photonics integrated *** review this rapidly-evolving research field,focusing on the epitaxial integration of antimonide lasers,the only technology covering the whole mid-to-far-infrared spectral *** explain how a dedicated molecular-beam epitaxy strategy allows for achieving high-performance GaSb-based diode lasers,InAs/AlSb quantum cascade lasers,and InAs/GaInSb interband cascade lasers by direct growth on on-axis(001)Si substrates,whereas GaAs-on-Si or GaSb-on-Si layers grown by metal-organic vapor phase epitaxy in large capability epitaxy tools are suitable templates for antimonide laser *** also show that etching the facets of antimonide lasers grown on Si is a viable approach in view of photonic integrated ***,this review shows that while diode lasers are sensitive to residual crystal defects,the quantum cascade and interband cascade lasers grown on Si exhibit performances comparable to those of similar devices grown on their native substrates,due to their particular band structures and radiative recombination *** device lifetimes have been extrapolated for interband cascade ***,routes to be further explored are also presented.

关键词： epitaxial quantum template

Fusion of spatiotemporal and thematic features of textual data for animal disease surveillance

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Information Processing in Agriculture 2023年第3期10卷 347-360页

作者： Sarah Valentin Renaud Lancelot Mathieu Roche CIRAD F-34398 MontpellierFrance ASTRE Univ MontpellierCIRADINRAEMontpellierFrance TETIS Univ MontpellierAgroParisTechCIRADCNRSINRAEMontpellierFrance Departement de Biologie Universite de SherbrookeSherbrookeQuebecCanada

Several internet-based surveillance systems have been created to monitor the web for animal health *** systems collect a large amount of news dealing with outbreaks related to animal *** identifying news articles that describe the same outbreak event is a key step to quickly detect relevant epidemiological information while alleviating manual curation of news *** paper addresses the task of retrieving news articles that are related in epidemiological *** tackle this issue using text mining and feature fusion *** main objective of this paper is to identify a textual representation in which two articles that share the same epidemiological content are *** compared two types of representations(i.e.,features)to represent the documents:(i)morphosyntactic features(i.e.,selection and transformation of all terms from the news,based on classical textual processing steps)and(ii)lexicosemantic features(i.e.,selection,transformation and fusion of epidemiological terms including diseases,hosts,locations and dates).We compared two types of term weighing(i.e.,Boolean and TF-IDF)for both *** combine and transform lexicosemantic features,we compared two data fusion techniques(i.e.,early fusion and late fusion)and the effect of features generalisation,while evaluating the relative importance of each type of *** conducted our analysis using a corpus composed of a subset of news articles in English related to animal disease *** results showed that the combination of relevant lexicosemantic(epidemiological)features using fusion methods improves classical morphosyntactic representation in the context of disease-related news *** lexicosemantic representation based on TF-IDF and feature generalisation(F-measure=0.92,r-precision=0.58)outperformed the morphosyntactic representation(F-measure=0.89,r-precision=0.45),while reducing the features *** the features into lower granular

关键词： Animal disease surveillance Text mining Ranking Fusion

Optimal Port Design Minimizing Standing Waves with A Posteriori Long Term Shoreline Sustainability Analysis

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China Ocean Engineering 2021年第6期35卷 802-813页

作者： Megan COOK Frédéric BOUCHETTE Bijan MOHAMMADI Léa SPRUNCK Nicolas FRAYSSE BRL Ingénierie Nı̂mes 30000France GEOSCIENCES-M University of MontpellierCNRSMontpellier 34090France GLADYS University of MontpellierCNRSLe Grau du Roi 30240France IMAG University of MontpellierCNRSMontpellier 34090France

Optimization theory is applied to a coastal engineering problem that is the design of a *** approach was applied to the redesign of La Turballe Port in order to increase the exploitable surface area and simultaneously reduce the occurrence of long waves within the *** defined the cost function as a weighted function of wave amplitude and with the chosen parameterization of the port,results show that an extended jetty and a widened mole yield a unique optimal *** work demonstrates that numerical optimization may be quick and efficient in the identification of port solutions consistent with classic engineering even in the context of complex problems.

关键词： optimization coastal engineering harbour design hydrodynamics shoreline analysis

Active MoS_(2)-based electrode for green ammonia synthesis

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Chinese Journal of Chemical Engineering 2024年第1期65卷 268-275页

作者： Xin Liu Lei Yang Tao Wei Shanping Liu Beibei Xiao School of Energy and Power Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China Institute Charles Gerhardt montpellier UMR-5253Universite de MontpellierCNRSENSCMPlace E.Bataillon34095 Montpellier Cedex 05France

Nitrogen electro-reduction under mild conditions is one promising alternative approach of the energyconsuming Haber-Bosch process for the artificial ammonia *** critical aspect to unlocking this technology is to discover the catalysts with high selectivity and *** this work,the N_(2)-to-NH_(3)conversion on the functional MoS_(2)is fully investigated by density functional theory calculations since the layered MoS_(2)provides the ideal platform for the elaborating copies of the nitrogenase found in nature,wherein the functionalization is achieved via basal-adsorption,basal-substitution or edge-substitution of transition metal *** results reveal that the edge-functionalization is a feasible strategy for the activity promotion;however,the basal-adsorption and basal-substitution separately suffer from the electrochemical instability and the NRR ***,MoS_(2)functionalized via edge W-substitution exhibits an exceptional *** energetically favored reaction pathway is through the distal pathway and a limiting potential is less than 0.20 ***,this work escalates the rational design of the high-effective catalysts for nitrogen fixation and provides the explanation why the predicated catalyst have a good performance,paving the guidance for the experiments.

关键词： Nitrogen reduction reaction Density functional theory calculations Molybdenum disulfide Electrochemistry Catalyst Thermodynamics

X chromosome inactivation and active X upregulation in therian mammals: facts, questions, and hypotheses

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Journal of Molecular Cell Biology 2015年第1期7卷 2-11页

作者： Reiner A.Veitia Frederic Veyrunes Samuel Bottani James A.Birchler Institut Jacques Monod ParisFrance universite Paris Diderot ParisFrance Institut des Sciences de l’Evolution de montpellier CNRS/Universite Montpellier IIMontpellierFrance Matiere et Systemes Complexes ParisFrance Division of Biological Sciences University of MissouriColumbiaMOUSA

X chromosome inactivation is a mechanism that modulates the expression of X-linked genes in eutherian females(XX).Ohno proposed that to achieve a proper balance between X-linked and autosomal genes,those on the active X should also undergo a 2-fold *** some support for Ohno's hypothesis has been provided through the years,recent genomic studies testing this hypoth-esis have brought contradictory results and fueled *** far,there are as many results in favor as against Ohno's hypothesis,depending on the nature of the datasets and the various assumptions and thresholds involved in the ***,they have con-firmed the importance of dosage balance between X-linked and autosomal genes involved in stoichiometric *** facts as well as questions and hypotheses are discussed below.

关键词： X inactivation X chromosome upregulation monoallelic expression imprinting dosage balance