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When parasitoids deal with the spatial distribution of their hosts: consequences for both partners

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Insect Science 2019年第5期26卷 923-931页

作者： Philippe Louapre Cecile Le Lann Thierry Hance Earth and Life Institue Universite Catholique de LouvainLouvain-la-NeuveBelgium cnrs Biogeosciences UMR 6282Universite Bourgogne Franche-ComteDijonFrance umr cnrs 6553 Ecobio University of Rennes 1Rennes CedexFrance

Insect parasitoids developing inside hosts face a true challenge: hosts are scattered in the field and their localization and selection require the use of complex and sometime confusing information. It was assumed for a long time that small-brained organisms like parasitoids have evolved simple and efficient behavioral mechanisms, leading them to be adapted to a given ecological situation, for example, the spatial distribution o f hosts in the habitat. However, hosts are not static and their distribution may also vary through generations and within the life of parasitoid individuals. We investigated if and how parasitoids deal with such a spatial com plexity in a m esocosm experiment. We used the Aphidius rhopalosiphi/Sitobion avenae parasitoid/host system to investigate if parasitoid females experiencing different host aggregation levels exhibit different foraging behaviors independently of the number of hosts in the environment. We showed that A. rhopalosiphi females exploited hosts more intensively both within and among patches at higher host aggregation levels. We discussed the adaptiveness of such behaviors in the light of evolution and biological control.

关键词： Aphidius rhopalosiphi foraging behavior parasitoid sequential adjustment Sitobion avenae spatial distribution

Soil properties, grassland management, and landscape diversity drive the assembly of earthworm communities in temperate grasslands

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Pedosphere 2021年第3期31卷 375-383页

作者： Kevin HOEFFNER Mathieu SANTONJA CécileMONARD Lou BARBE Mathilde LEMOING Daniel CLUZEAU University of Rennes CNRSECOBIO UMR 6553Rennes F-35000France INRAE AGROCAMPUS OUEST UMR SASRennes F-35000France Aix Marseille Université Avignon UniversitéCNRSIRDIMBEMarseille F-13397France

Earthworms are widespread soil organisms that contribute to a wide range of ecosystem *** such,it is important to improve our knowledge,still scanty,of the factors that drive the assembly of earthworm *** aim of the present study was to conjointly evaluate the effects on the assembly of earthworm communities of i)soil properties(texture,organic matter content,and pH),ii)grassland management(grassland age,livestock unit,and type of fertilization),iii)landscape diversity(richness,diversity of surrounding habitats,and grassland plant diversity),and iv)presence of *** study was conducted in temperate grasslands of Brittany,*** were sampled in 24 grasslands and,in three of these grasslands,they were sampled near a hedgerow or near a ditch(control without a hedgerow).Soil properties explained the larger portion of the variation in the earthworm community parameters compared to grassland management or landscape *** increase in soil organic matter content and pH were the most favorable factors for earthworm abundance and biomass,in particular for endogeic *** grassland management,the increase in the livestock unit was the most damaging factor for earthworm communities,in particular for the anecic earthworm biomass and endogeic species ***,landscape diversity negatively affected the total earthworm abundance and epigeic earthworm biomass,but it was related to an increase in the epi-anecic *** a finer scale,we also demonstrated that the presence of hedgerows surrounding grasslands enhanced earthworm species richness,especially within the epigeic and anecic ecological *** study highlights that the earthworm ecological categories respond specifically to environmental filters;further studies need to be conducted to elucidate the factors that drive the assembly of earthworm communities at this ecological category *** recommend that policymakers should act on landscape man

关键词： ecological categoryfield marginhedgerowlivestock unitsoil organic mattersoil PHtrampling

One-pot Synthesis and X-ray Structure Determination of 7-(Diethylamino)-3-(4-aminophenyl)coumarin

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Chinese Journal of Structural Chemistry 2015年第12期34卷 1841-1844页

作者： KULAI Ihor MALLET-LADEIRA Sonia KOVTUNENKO Volodymyr VOITENKO Zoia IMRCP CNRS UMR 5623 University of Toulouse Department of Chemistry Taras Shevchenko National University of Kyiv ICT FR CNRS 2599 University of Toulouse

7-（Diethylamino）-3-（4-aminophenyl）coumarin has been synthesized in a new one-pot synthesis by a three-step process starting from 4-（diethylamino）salicylaldehyde and 4-nitrophenylacetonitrile. The product was obtained in a good yield with a high degree of purity and characterized by NMR, IR and HR-MS. The orange crystals of the title compound were grown from ethyl acetate solution. The solid state structure was established by X-ray crystallography analysis. The crystal belongs to the orthorombic system, space group Pccn with a = 11.1095（5）, b = 33.0187（15）, c = 17.2865（7） A, V= 6341.1（5） A3, C19H20N2O2, Mr = 308.37, ρcalc = 1.292 g·cm^-3, = 0.085 mm^-1, F（000） = 2624, the final R = 0.0480 and wR = 0.1265 （I〉 2σ（I））.

关键词： coumarin dye crystal structure fluorescence one-pot synthesis

Parametric instability of a liquid metal sessile drop under the action of low-frequency alternating magnetic fields

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Journal of Hydrodynamics 2013年第2期25卷 300-308页

作者：雷作胜郭加宏 FAUTRELLE Yves ERNST Roland ETAY Jacqueline 任忠鸣 Shanghai Key Laboratory of Modern Metallurgy and Materials Processing Shanghai University SIMAP-EPM Laboratory Grenoble Institute of Technology/CNRS UMR 5266 France Shanghai Institute of Applied Mathematics and Mechanics Shanghai University SIMAP-EPM Laboratory Grenoble Institute of Technology/CNRS UMR 5266France

A 2-D mathematical model is developed in order to simulate a parametric electromagnetic instability oscillation process of a liquid metal droplet under the action of low frequency magnetic field. The Arbitrary Lagrangian-Eulerian （ALE） method and weak form constraint boundary condition are introduced in this model for implementation of the surface tension and electromagnetic force on liquid droplet free surface. The results of the numerical calculations indicate the appearance of various regimes of oscillation. It is found that according to the magnetic field frequency various types of oscillation modes may be found. The oscillation is originated from an instability phenomenon. The stability diagram of liquid metal droplet in the parameter space of magnetic frequency and magnetic flux density is determined numerically. The diagram is very similar to that found in the so-called parametric instability.

关键词： sessile drop parametric instability low-frequency alternating magnetic fields numerical simulation

Multiplexing technology for in vitro diagnosis of pathogens： the key contribution of phosphorus dendrimers

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Science China Materials 2018年第11期61卷 1454-1461页

作者： Jean Pierre Majoral Jean Marie Francois Richard Fabre Alice Senescau Serge Mignani Anne-Marie Caminade Laboratoire de Chimie de Coordination du cnrs 31077 Toulouse Cedex 4France LCC-cnrs Universit6 de Toulouse CNRSToulouseFrance Dendris 31670 LabegeFrance LISBP UMR CNRS 5504 INRA 79231077 Toulouse Cedex 04France Universite Paris Descartes PRES Sorbonne Paris Cite CNRS-UMR 860Laboratoire de Chimie et de Biochimie Pharmacologiques et Toxicolgique75006 ParisFrance

After the microbiology based on Pasteur's method and polymerase chain reaction(PCR), the diagnosis company named Dendris has proposed a third-generation of diagnosis enabling the search of a broad range of pathogens with strong sensitivity and specificity. This extraordinary profile was possible thanks to the use of phosphorus dendrimers for which various techniques of deposition on a given support were investigated and described and analyzed in this report.

关键词： phosphorus dendrimers diagnosis DNA arrays multiplexing technology

Inspection of free energy functions in gradient crystal plasticity

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Acta Mechanica Sinica 2013年第6期29卷 763-772页

作者： Samuel Forest Nicolas Guninchault Centre des Matriaux Mines ParisTechCNRS UMR 7633 BP 8791003 Evry CedexFrance

The dislocation density tensor computed as the cud of plastic distortion is regarded as a new constitutive variable in crystal plasticity. The dependence of the free energy function on the dislocation density tensor is explored starting from a quadratic ansatz. Rank one and logarithmic dependencies are then envisaged based on considerations from the statistical theory of dislocations. The rele- vance of the presented free energy potentials is evaluated from the corresponding analytical solutions of the periodic two-phase laminate problem under shear where one layer is a single crystal material undergoing single slip and the second one remains purely elastic.

关键词： Gradient plasticity Crystal plasticity Continuum thermodynamics Dislocation density tensor Read- Shockley energy

Parameters Affecting the Fuel Cell Reactions on Platinum Bimetallic Nanostructures

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Electrochemical Energy Reviews 2023年第1期6卷 830-853页

作者： Nicolas Alonso‑Vante IC2MP UMR-CNRS 7285University of Poitiers4 rue Michel Brunet86072 PoitiersFrance

In this paper the electrochemical properties of some platinum-based nanoalloys are *** revision is centered on electrocatalytic materials generated via the carbonyl chemical route(CCR).In considering the effects of segregation in these bimetals,the reaction of the hydrogen oxidation(HOR)and oxygen reduction(ORR)in the alkaline medium was *** reaction kinetics of these electrochemical processes in the alkaline electrolyte is still a *** the design of high-performance platinum-based electrocatalysts,it is of importance to know that the kinetics of HOR and ORR also depends on the Pt *** electrochemical analysis,based on the study of Pt nanoalloyed surfaces with different Pt-adsorbate interactions,was taken into account.A clear trend in the HOR as well as the ORR activity,in the alkaline electrolyte,was established,revealing that the activity changes in the order PtSn/C

关键词： Electrocatalysts HOR HER ORR Pt-based materials Bimetallic Carbon domains

Approximants in annealed IQC(Icosahedral Quasicrystal)-DQC(Decagonal Quasicrystal) pseudo-binary alloys

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中国有色金属学会会刊：英文版 2003年第6期13卷 1360-1366页

作者：雷奕 J.M.Dubois M.Calvo-Dahlborg 黑祖昆 P.Weisbecker 董闯 State Key Laboratory for Materials Modification LSG2M cnrs-umr7584 Institute of Material & Technology

The structure and microstructure of constituent phases in annealed IQC100-xDQCx alloys, made from mixtures of (Al62Cu25.5Fe12.5) icosahedral quasicrystal （IQC） and (Al70Co15Ni15) decagonal quasicrystal （DQC）, were studied by X-ray diffractometry（XRD）, scanning electron microscopy （SEM）, and energy-dispersive X-ray spectroscopy （EDAX）. These constituent phases are mostly approximants: λ, β and τ3. In addition, an Al-Cu-Co DQC phase is observed in (IQC80DQC20) alloy. The nature of these approximants and their relationship with the quasicrystals（QCs） are discussed; and the evolution of these phases is interpreted by the shifting of their e/a-constant lines in the Al-（Cu, Ni）-（Fe, Co） pseudo-ternary phase diagrams.

关键词：二元合金准晶 IQC DQC 近似解退火相图

Control of light emission of quantum emitters coupled to silicon nanoantenna using cylindrical vector beams

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Light(Science & Applications) 2023年第10期12卷 2248-2255页

作者： Martin Montagnac Yoann Brûlé Aurélien Cuche Jean-Marie Poumirol Sébastien J.Weber Jonas Müller Guilhem Larrieu Vincent Larrey Franck Fournel Olivier Boisron Bruno Masenelli Gérard Colas des Francs Gonzague Agez Vincent Paillard CEMES-cnrs Universitéde ToulouseToulouseFrance ICB Universitéde BourgogneCNRSDijonFrance LAAS-cnrs Universitéde ToulouseToulouseFrance CEA-LETI UniversitéGrenoble-AlpesGrenobleFrance Universitéde Lyon UniversitéLyon 1CNRS UMR 5510ILMVilleurbanneFrance Universitéde Lyon INSA LyonCNRSEcole Centrale de LyonUniversitéLyon 1CPEUMR 5270INLVilleurbanneFrance Bruno Masenelli

Light emission of europium(Eu^(3+))ions placed in the vicinity of optically resonant nanoantennas is usually controlled by tailoring the local density of photon states(LDOS).We show that the polarization and shape of the excitation beam can also be used to manipulate light emission,as azimuthally or radially polarized cylindrical vector beam offers to spatially shape the electric and magnetic fields,in addition to the effect of silicon nanorings(Si-NRs)used as *** photoluminescence(PL)mappings of the Eu^(3+)transitions and the Si phonon mappings are strongly dependent of both the excitation beam and the Si-NR *** experimental results of Raman scattering and photoluminescence are confirmed by numerical simulations of the near-field intensity in the Si nanoantenna and in the Eu^(3+)-doped film,*** branching ratios obtained from the experimental PL maps also reveal a redistribution of the electric and magnetic emission *** results show that it could be possible to spatially control both electric and magnetic dipolar emission of Eu^(3+)ions by switching the laser beam polarization,hence the near field at the excitation wavelength,and the electric and magnetic LDOS at the emission *** paves the way for optimized geometries taking advantage of both excitation and emission processes.

关键词： excitation cylindrical spatially