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Cellular models of stress resistance may pave ways to fight neurodegenerative diseases

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Neural Regeneration Research 2025年第9期20卷 2579-2580页

作者： Thu Nguyen Minh Pham Christian Behl Institute of Pathobiochemistry University Medical Center of the Johannes Gutenberg UniversityMainzGermany

Alzheimer's disease(AD),the most common form of neurodegeneration,is characterized by selective neuronal vulnerability and brain regionselective neuron *** entorhinal cortex and hippoc,ampal CA1 projection neurons are at greater risk in AD whereas other regions display resistance to ***,the cerebellum,a phylogenetically very old region,is affected only very late in the disease progression.

关键词： cortex resistance Alzheimer

A high-power electromagnetic source for disabling improvised explosive devices

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High Voltage 2024年第2期9卷 403-409页

作者： Laurent Ariztia Njomza Ibrahimi Alexey Zhabin Antoine Silvestre de Ferron Marc Rivaletto Edson Martinod Valérie Bertrand Bucur Novac Laurent Pécastaing Universite de Pau et des Pays de l’Adour E2S UPPASIAMEPauFrance XLIM UMR CNRS BriveLimogesFrance CISTEME LimogesFrance Wolfson School of Mechanical Electrical and Manufacturing EngineeringLoughborough UniversityLoughboroughLeicestershireUK

Ultra-wideband(UWB)microwave sources driven by specialised pulsed power generators have experienced a considerable development in the last decade due to their wide domain of new applications such as defence or counter-terrorism *** authors present the main findings of a research dedicated to the development of a pulsed power-driven electromagnetic field source for disabling improvised explosive devices(IED).The pulsed power generator driving the source is a 13-stage compact Marx producing voltage pulses reaching an amplitude of 0.5 MV,with a pulse repetition frequency(PRF)of up to 100 *** generator is coupled to a bipolar pulse forming line,providing bipolar pulses with a dV/dt of around 1.6 MV/*** pulsed power system feeds an array composed of 16 Koshelev-type UWB antennas through an impedance matching *** resulting electromagnetic source is capable to produce pulsed electric fields(PEFs)having a figure-of-merit(FOM)of 1 ***,practical experiments were carried out to study the effects of the PEFs on *** targets used in the present study are M2B type flashbulbs,known to have the same susceptibility as the US army M6 *** configurations of wires(shielded,twisted,etc)with different lengths were used in connecting items inside these *** tests were performed by placing the flashbulbs at different distances to determine the essential parameters(i.e.,amplitude,duration,and frequency range)of the PEFs required to trigger *** overview of the experimental campaign and the main findings are also presented followed by conclusions.

关键词： power bipolar source

Functional responses to deforestation in fish communities inhabiting neotropical streams and rivers

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Ecological Processes 2023年第1期12卷 716-732页

作者： Isabel Cantera Céline Jézéquel Tony Dejean Jérôme Murienne Régis Vigouroux Alice Valentini Sébastien Brosse Department of Environmental Science and Policy Universitàdegli Studi di MilanoVia Celoria 2620133 MilanItaly Laboratoire Evolution et DiversitéBiologique UMR5174-UniversitéPaul SabatierCNRSIRD118 Route de Narbonne31062 ToulouseFrance SPYGEN Savoie Technolac-BP 27417 Rue du Lac Saint-André73375 Le Bourget-du-Lac CedexFrance HYDRECO Laboratoire Environnement de Petit SautB.P 82397388 Kourou CedexFrench GuianaFrance

Background Deforestation is a widespread disturbance for neotropical freshwater *** biodiversity declines have been associated with deforestation,its functional consequences for stream and river fish faunas remain poorly *** this study,we explored how deforestation affects the different facets of the functional structure of fish communities inventoried using environmental DNA metabarcoding in 64 river and 35 stream sites of French ***,we investigated how functional richness,divergence,evenness and identity of fish faunas are affected by *** We showed that anthropogenic disturbances in French Guiana are modifying the functional diversity of freshwater fish *** disturbances not only affected the amount of functional traits held by the communities but also the identity of the traits and the internal structure of the functional ***,different facets of the functional diversity supported by fish assemblages were *** streams,deforestation did not affect the overall diversity of traits but reduced functional redundancy,underlined by a shift in functional identity towards assemblages dominated by pelagic *** contrast,river fish faunas experienced a decline in functional richness,paired with shifts in functional identity and a loss of fish species with extreme *** The response to deforestation differed between streams and rivers,but it supports the hypothesis that deforestation is linked to functional changes in fish *** diminishing the range of the functions in rivers or by jeopardizing the redundancy of functions in streams,deforestation could severely hamper the functioning and stability of neotropical freshwater ecosystems.

关键词： eDNA Traits Functional space Richness Divergence Evenness Identity Gold mining

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Stochastic framework for modeling the linear apparent behavior of complex materials:Application to random porous materials with interphases

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Acta Mechanica Sinica 2013年第6期29卷 773-782页

作者： J.Guilleminot T.T.Le C.Soize Universit Paris-Est Laboratoire Modlisation et Simulation Multi EchelleMSME UMR8208 CNRS5 Bd Descartes77454 Marne la ValleFrance

This paper is concerned with the modeling of randomness in multiscale analysis of heterogeneous materials. More specifically, a framework dedicated to the stochastic modeling of random properties is first introduced. A probabilistic model for matrix-valued second-order random fields with symmetry propertries, recently proposed in the literature, is further reviewed. Algorithms adapted to the Monte Carlo simulation of the proposed representation are also provided. The derivations and calibration procedure are finally exemplified through the modeling of the apparent properties associated with an elastic porous microstructure containing stochastic interphases.

关键词： Apparent properties MaxEnt Probabilistic model

Pressureless sintering behavior and properties of Ag-SnO_2

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Rare Metals 2019年第1期38卷 35-41页

作者： Henri Desplats Elodie Brisson Philippe Rogeon Patrick Carré Alexandre Bonhomme Department of Materials Engineering IRDL FRE CNRS 3744University of South Brittany Schneider Electric-Electropole 31 rue Pierre Mendes France

In this study, the results of measurements on pressureless sintering behavior of Ag-SnO_2(88%wt Ag,12%wt SnO_2) pellets were reported. Dilatometric measurements, relative densities, hardness values, rupture transverse strength and electrical conductivities function of sintering temperatures were presented. A constant thermal expansion coefficient was determined, and a threshold temperature of densification(T_d) was exhibited. Sintering kinetics were reported for different temperatures. Hardness values were measured, and no increase in hardness is found under Td. Three-points bending tests were used to determine the transverse rupture strength whose evolution appears importantly well under Td. In the same manner, the increase in initial electrical conductivities begins well under Td. Under the threshold temperature, the relative increase in electrical conductivity is found to be independent of initial density of green compact pellets. This work highlights different evolutions in function of sintering temperature for the electrical conductivity and transverse rupture strength on the one hand, and for the densification and hardness on the other hand.

关键词： Ag-SnO2 Pressureless sintering Dilatometry Mechanical properties Electrical conductivity

Strong dependency of the tribological behavior of CuZr-based bulk metallic glasses on relative humidity in ambient air

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Friction 2023年第5期11卷 785-800页

作者： Solène BARLEMONT Paul LAFFONT Rémi DAUDIN Alexis LENAIN Guillaume COLAS Pierre-Henri CORNUAULT Femto-ST Institute Department of Applied MechanicsUniversity of Bourgogne Franche-ComtéCNRS/UFC/ENSMM/UTBMBesançon 25030France University of Grenoble Alpes CNRSSIMaPGrenoble 38000France Vulkam Inc.Amorphous metal micro casting Gières 38610France

Thanks to their outstanding mechanical properties,Bulk Metallic Glasses(BMGs)are new alternatives to traditional crystalline metals for mechanical and micromechanical applications including power ***,the tribological properties of BMGs are still poorly understood,mostly because their amorphous nature induces counter intuitive responses to friction and *** the present study,four different BMGs(Cu_(47)Zr_(46)Al_(7),Zr_(46)Cu_(45)Al_(7)Nb_(2),Zr_(60)Cu_(28)Al_(12),and Zr_(61)Cu_(25)Al_(12)Ti_(2))underwent ball-on-disc friction tests against 100Cr6 steel balls(American Iron and Steel Institute(AISI)52100)at different relative humidities(RHs)ranging from 20%to 80%.Controlling humidity enabled to observe a high repeatability of the friction and wear responses of the ***,the friction coefficient decreased by a factor of 2 when the humidity was increased,and the wear rate of BMGs was particularly low thanks to a 3rd-body tribolayer that forms on the BMG surface,composed of oxidized wear particles originating from the *** morphology of this tribolayer is highly correlated to *** study also identifies how the tribolayer is built up from the initial contact until the steady state is achieved.

关键词： Bulk Metallic Glasses(BMGs) tribology oxide transfer layer relative humidity(RH)

Object removal from complex videos using a few annotations

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Computational Visual Media 2019年第3期5卷 267-291页

作者： Thuc Trinh Le Andrés Almansa Yann Gousseau Simon Masnou LTCI T′el′ecom ParisTechUniversit′e Paris-Saclay75013 ParisFrance MAP5 CNRS&Universit′e Paris Descartes75006 ParisFrance Univ Lyon Universit′e Claude Bernard Lyon 1CNRS UMR 5208Institut Camille Jordan69622 VilleurbanneFrance

We present a system for the removal of objects from videos. As input, the system only needs a user to draw a few strokes on the first frame, roughly delimiting the objects to be removed. To the best of our knowledge, this is the first system allowing the semi-automatic removal of objects from videos with complex backgrounds. The key steps of our system are the following: after initialization, segmentation masks are first refined and then automatically propagated through the video. Missing regions are then synthesized using video inpainting techniques. Our system can deal with multiple, possibly crossing objects, with complex motions, and with dynamic textures. This results in a computational tool that can alleviate tedious manual operations for editing high-quality videos.

关键词： object removal object segmentation object tracking video inpainting video completion

Auger effect in weakly confined nanocrystals

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Light(Science & Applications) 2023年第8期12卷 1454-1456页

作者： Jiawen Liu Laurent Coolen Laboratoire de Physique de I'Ecole Normale Superieure ENSUniversite PSLCNRSSorbonne UniversiteUniversite Paris CiteF-75005 ParisFrance Sorbonne Universite CNRSInstitut de NanoSciences de ParisINSPF-75005 ParisFrance

An extensive analysis of biexciton luminescence in high-quality,large perovskite CsPbBr_(3) nanocrystals shows how the biexciton Auger decay rate deviates from the"universal"volume scaling as the exciton confinement b... 详细信息

关键词： weakly confined perovskite

The TELOMERE REPEAT BINDING proteins TRB4 and TRB5 function as transcriptional activators of PRC2-controlled genes to regulate plant development

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Plant Communications 2024年第7期5卷 178-199页

作者： Simon Amiard Léa Feit Emmanuel Vanrobays Lauriane Simon Samuel Le Goff Loriane Loizeau Léa Wolff Falk Butter Clara Bourbousse Fredy Barneche Christophe Tatout Aline V.Probst iGReD CNRSInsermUniversite Clermont Auvergne63000 Clermont-FerrandFrance Institut de biologie de I’Ecole normale superieure(IBENS) Ecole normale superieureCNRSINSERMUniversite PSLParisFrance Institute of Molecular Biology 55128 MainzGermany

Plant-specific transcriptional regulators called TELOMERE REPEAT BINDING proteins(TRBs)combine two DNA-binding domains,the GH1 domain,which binds to linker DNA and is shared with H1 histones,and the Myb/SANT domain,which specifically recognizes the telobox DNA-binding site ***1,TRB2,and TRB3 proteins recruit Polycomb group complex 2(PRC2)to deposit H3K27me3 and JMJ14 to remove H3K4me3 at gene promoters containing telobox motifs to repress ***,we demonstrate that TRB4 and TRB5,two related paralogs belonging to a separate TRB clade conserved in spermatophytes,regulate the transcription of several hundred genes involved in developmental responses to environmental ***4 binds to several thousand sites in the genome,mainly at transcription start sites and promoter regions of transcriptionally active and H3K4me3-marked genes,but,unlike TRB1,it is not enriched at H3K27me3-marked gene ***,TRB4 can physically interact with the catalytic components of PRC2,SWINGER,and CURLY LEAF(CLF).Unexpectedly,we show that TRB4 and TRB5 are required for distinctive phenotypic traits observed in clf mutant plants and thus function as transcriptional activators of several hundred CLF-controlled genes,including key flowering *** further demonstrate that TRB4 shares multiple target genes with TRB1 and physically and genetically interacts with members of both TRB ***,these results reveal that TRB proteins engage in both positive and negative interactions with other members of the family to regulate plant development through both PRC2-dependent and-independent mechanisms.

关键词： chromatin TRB proteins transcriptional regulation PRC2 plant development