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International Journal of Minerals,Metallurgy and Materials 2016年第11期23卷 1340-1345页

作者： Mohamed Benchikhi Rachida El Ouatib Sophie Guillemet-Fritsch Lahcen Er-Rakho bernard Durand Laboratoire de Physico-Chimie des Matériaux Inorganiques Faculté des Sciences Ain Chock Université Hassan Ⅱ Casablanca Institut Carnot CIRIMAT CNRS Université de Toulouse

We report a simple method for preparing copper（II） molybdate（CuMoO_4） powders via a combustion-like process. A gel was first prepared by the polymerizable complex method, where citric acid was used as a complexing and polymerizing agent and nitric acid was used as an oxidizing agent. The thermal decomposition behavior of the（CuMo）-precursor gel was studied by thermogravimetry–differential thermal analysis（TG–DTA）, Fourier transform infrared spectroscopy（FTIR）, and X-ray diffraction（XRD）. We observed that the crystallization of CuMoO_4 powder was completed at 450°C. The obtained homogeneous powder was composed of grains with sizes in the range from 150 to 500 nm and exhibited a specific surface area of approximately 5 m^2/g. The average grain size increased with increasing annealing temperature. The as-prepared CuMoO_4 crystals showed a strong green photoluminescence emission at room temperature under excitation at 290 nm, which we mainly interpreted on the basis of the Jahn-Teller effect on [MoO_4^（2-）] complex anions. We also observed that the photoluminescence intensity increased with increasing crystallite size.

关键词： copper molybdate chemical synthesis photoluminescence Jahn-Teller effect

Functional trait composition of carabid beetle communities predicts prey suppression through both mass ratio and niche complementarity mechanisms

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Insect Science 2024年第2期31卷 562-574页

作者： Abdelhak Rouabah Francoise Lasserre-Joulin Sylvain Plantureux Simon Taugourdeau bernard Amiaud Universite de Loraine INRAELAENancyF-54000France UMR SELMET CIRADINRAEInstitut AgroUniversite de MontpellierMontpellier34000France CIRAD UMR SELMET-PPZSDakarSéenegal UMR Siva Universitéde LorraineAgroParisTechINRAEVandoeuvreLes Nancy54506France

Several components of predator functional diversity have been hypothesized to influence prey suppression through either niche complementarity or mass ratio ***,most studies have used a functional group approach when assessing the role of these predators in ecosystem *** adopting a trait-based approach,we evaluated the relative contributions of carabid diversity components in predicting prey *** results highlight the importance of both taxonomic and functional diversity components of carabids as key drivers of prey *** suppression was best predicted by carabid densities,with the dominance of Poecilus cupreus potentially driving the positive effect of community total abundance through the mass ratio *** suppression increased with increasing the density of large *** addition,carabid eye diameter and antennal length were key functional traits for predicting prey ***,prey suppression increased with increasing carabid functional richness following the niche complementarity *** contrast to functional richness,functional evenness and functional divergence of carabid communities were weakly correlated with prey *** identifying which diversity components of carabid communities contribute the most to increase prey suppression,our results can guide efforts aiming to predict the relationship between diversity of these predators and ecosystem functioning.

关键词： abundance distribution biological control body size ecosystem function functional richness predator-prey interactions

Natural polyphenols effects on protein aggregates in Alzheimer＇s and Parkinson＇s prion-like diseases

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Neural Regeneration Research 2018年第6期13卷 955-961页

作者： aline freyssin guylène page bernard fauconneau agnès rioux bilan University of Poitiers EA380-8 NEUVACOD (Neurovascular Unit and Cognitive Disorders) Pole Biologie Sante Poitiers France

Alzheimer＇s and Parkinson＇s diseases are the most common neurodegenerative diseases. They are characterized by protein aggregates and so can be considered as prion-like disease. The major components of these deposits are amyloid peptide and tau for Alzheimer＇s disease, α-synuclein and synphilin-1 for Parkinson＇s disease. Drugs currently proposed to treat these pathologies do not prevent neurodegenerative processes and are mainly symptomatic therapies. Molecules inducing inhibition of aggregation or disaggregation of these proteins could have beneficial effects, especially if they have other beneficial effects for these diseases. Thus, several natural polyphenols, which have antioxidative, anti-inflammatory and neuroprotective properties, have been largely studied, for their effects on protein aggregates found in these diseases, notably in vitro. In this article, we propose to review the significant papers concerning the role of polyphenols on aggregation and disaggregation of amyloid peptide, tau, α-synuclein, synphilin-1, suggesting that these compounds could be useful in the treatments in Alzheimer＇s and Parkinson＇s diseases.

关键词： natural polyphenols protein aggregates Alzheimer's disease amyloid peptide amyloid plaques hyperphosphorylated tau Parkinson's disease a-synuclein synphilin-I

The influence of mitochondria in epigenetics revealed through naturally occurring fish cybrids

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Current Zoology 2012年第1期58卷 138-145页

作者： Angers, bernard Dallaire, Antoine Vervaet, Simon Vallières, Francis Angers, Annie Department of Biological Sciences Université de Montréal C.P. 6128 succ. Centre-Ville Montréal Québec Canada H3C 3J7

Epigenetic processes are important mechanisms for phenotypic changes that occur in response to the environment. As such, it is expected that the alteration of cytoplasmic composition （the immediate environment of nuclei） results in the modifica- tion of the methylome and the expression of the nuclear genome. Cytoplasmic hybrids （or cybrids） are an ideal model to study the influence of mitochondria on gene expression. In this study, we take advantage of the natural of two biotypes that have a similar nuclear genome type Chrosomus eos, but harbor mitochondria from different species （C. eos in wild type or C. neogaeus in cybrids） to assess the effects of mitochondria on DNA methylation profiles and protein expression of the nuclear ge- nome. Comparison between these biotypes is particularly relevant given their recent divergence and their low level of genetic dif- ferentiation. Variations of DNA methylation assessed on tissues from different embryonic origins revealed the distinct profiles of cybrid and wild type populations. Differences are more pronounced between wild type and cybrids than between populations of a given biotype. The proteome is also more different between biotypes than within a given biotype. These results indicate a strong influence of mitochondria on the nuclear genome, which remains detectable in different genetic and environmental contexts. These changes in the methylome and proteome of cybrids are expected to reflect the adjustments imposed by the coexistence of nuclear and mitochondrial genomes from different species [Current Zoology 58 （1）： 138-145, 2012].

关键词： Epigenetics Mitochondria Chrosomus Phenotype

Rainbow guiding of the lowest-order antisymmetric Lamb mode in phononic crystal plate

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Science China(Technological Sciences) 2019年第3期62卷 458-463页

作者： ZHAO JinFeng YUAN WeiTao BONELLO bernard DJAFARI-ROUHANI Bahram PAN YongDong ZHONG Zheng School of Aerospace Engineering and Applied Mechanics Tongji University INSP UMR CNRS 7588 Sorbonne Université UPMC Université Paris 06 Institut d'Electronique de Microélectronique et de Nanotechnologie (IEMN-UMR CNRS 8520) Université de Lille Sciences et Technologies School of Science Harbin Institute of Technology

The modern acoustic circuits have experienced significant progress with the development of artificial structures, including phononic crystals, metamaterials or metasurfaces. Among the most intensive topics, the reconfigurable acoustic guides are achieved through several mechanisms. In this work, we report on the rainbow guiding for the lowest-order antisymmetric Lamb(A_0) mode in a phononic crystal plate, where the linear waveguides are constituted by erecting aligned pillars either solid or hollow. We show both numerically and experimentally that the whispering gallery modes(WGMs) in the hollow pillars can be generated by the defect mode that propagates in the waveguide. Then, the reemission of A_0 mode by the WGMs to the outer lateral areas can lead to spatial control of frequency selective wave guidance called "rainbow guiding". Our approach allows for an accurate control of the wave guiding and facilitates the integration of waveguides within other devices in the acoustic circuits.

关键词： whispering gallery mode rainbow guiding phononic crystal

Elaboration of AlSi10Mg casting alloys using directional solidification processing

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International Journal of Minerals,Metallurgy and Materials 2015年第5期22卷 509-515页

作者： Khadoudja Ghedjati Eric Fleury Mohamed Seghir Hamani Mostefa Benchiheub Khaider Bouacha bernard Bolle Systems and Advanced Materials Laboratory (LASMA) Department of Physics Faculty of Science Badji Mokhtar University of Annaba Microstructure Investigation and Material Mechanic Laboratory (LEM3) CNRS Lorraine-Metz University Faculty of Science Souk Ahras University Foundry Research Laboratory (LRF) Department of Physics Faculty of Science Badji Mokhtar University of Annaba

The effects of pulling velocity on the solidification behavior and microstructural parameters of A1Sil0Mg alloys prepared in a Bridgman-type directional solidification furnace were investigated. The microstructure, particularly the secondary dendritic arm spacing （SDAS）, and the Brinell hardness （BH） of the solidified A1Sil0Mg alloys were characterized for samples with cylindrical shapes and differ- ent conicities （θ = 0°, 5°, and 10°）. Microstructural studies revealed an increased density of ct-A1 phase dendrites and a decreased interden- dritic distance with increasing pulling velocity. The dendrites were found to be preferentially oriented along the pulling direction for low pulling velocities. For larger pulling velocities, the dendrites grew first in the cooling direction but then broke as others nucleated and coars- ened. The HB values of the solidified samples increased as the pulling velocity increased. In regard to sample conicity, smaller dendrites were observed for an apex angle of θ = 5°, resulting in the largest HB value. This result was interpreted in terms of the favorable orientation of the dendrite along the pulling direction.

关键词： aluminum-silicon-magnesium alloys directional solidification Bridgman technique mierostructure hardness heat flow growth

Classification on Grade, Price, and Region with Multi-Label and Multi-Target Methods in Wineinformatics

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Big Data Mining and Analytics 2020年第1期3卷 1-12页

作者： James Palmer Victor S.Sheng Travis Atkison bernard Chen the Department of Computer Science University of Central ArkansasConwayAR 72034USA the Department of Computer Science University of AlabamaTuscaloosaAL 35487USA

Classifying wine according to their grade,price,and region of origin is a multi-label and multi-target problem in *** wine reviews as the attributes,we compare several different multi-label/multitarget methods to the single-label method where each label is treated *** explore both single-label and multi-label approaches for a two-class problem for each of the labels and we explore both single-label and multi-target approaches for a four-class problem on two of the three labels,with the third label remaining a twoclass *** terms of per-label accuracy,the single-label method has the best performance,although some multi-label methods approach the performance of ***,multi-label/multi-target metrics approaches do exceed the performance of the single-label method.

关键词： classification informatics machine learning multi-label multi-target support vector machines wine wineinformatics

Deep Convolutional Neural Network Approach for COVID-19 Detection

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Computer Systems Science & Engineering 2022年第7期42卷 201-211页

作者： Yu Xue bernard-Marie Onzo Romany F.Mansour Shoubao Su School of Computer and Software Nanjing University of Information Science and TechnologyNanjing210044China Engineering Research Center of Digital Forensics Ministry of EducationNanjing University of Information Science and TechnologyNanjingChina Department of Mathematics Faculty of ScienceNew Valley UniversityEl-Kharja72511Egypt Jiangsu Key Laboratory of Data Science and Smart Software Jinling Institute of TechnologyNanjing211169China

Coronavirus disease 2019(Covid-19)is a life-threatening infectious disease caused by a newly discovered strain of the *** by the end of 2020,Covid-19 is still not fully understood,but like other similar viruses,the main mode of transmission or spread is believed to be through droplets from coughs and sneezes of infected *** accurate detection of Covid-19 cases poses some questions to scientists and *** two main kinds of tests available for Covid-19 are viral tests,which tells you whether you are currently infected and antibody test,which tells if you had been infected ***-tine Covid-19 test can take up to 2 days to complete;in reducing chances of false negative results,serial testing is *** image processing by means of using Chest X-ray images and Computed Tomography(CT)can help radiologists detect the *** imaging approach can detect certain characteristic changes in the lung associated with *** this paper,a deep learning model or tech-nique based on the Convolutional Neural Network is proposed to improve the accuracy and precisely detect Covid-19 from Chest Xray scans by identifying structural abnormalities in scans or X-ray *** entire model proposed is categorized into three stages:dataset,data pre-processing andﬁnal stage being training and classiﬁcation.

关键词： COVID-19 deep learning convolutional neural network X-ray

微机电系统谐振器原子力显微镜探针设计与检测(英文)

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强激光与粒子束 2015年第2期27卷 107-111页

作者：熊壮 bernard Legrand 中国工程物理研究院电子工程研究所四川绵阳621999 Institut d’Electronique de Microélectronique et de Nanotechnologie-IEMN CNRS UMR 8520NAM6 GroupFrance

为克服既有原子力显微镜(AFM)悬臂式探针的谐振频率难以超过3.5 MHz,Q值低、成像速度低及在液体中成像效果欠佳等缺点,设计并制作了一种基于微机电系统(MEMS)谐振器的I2形探针,并成功实现了成像实验。为更进一步提高I2形探针的力灵敏度... 详细信息

为克服既有原子力显微镜(AFM)悬臂式探针的谐振频率难以超过3.5 MHz,Q值低、成像速度低及在液体中成像效果欠佳等缺点,设计并制作了一种基于微机电系统(MEMS)谐振器的I2形探针,并成功实现了成像实验。为更进一步提高I2形探针的力灵敏度,从结构设计和检测方法入手,对原有探针进行改进。设计了简单有效的电阻差分检测方法,成功去处了输入端与输出端的耦合现象;采用局部离子注入的方法,提高了压阻敏感的传输效率。实验结果显示,在输入信号相同的条件下,改进后探针的输出信号与原有探针相比,输出信号得到了明显提高。计算结果表明,采用新方法制作的探针可使力灵敏度提高10倍以上。

关键词：微机电系统谐振器热执行压阻敏感原子力显微镜探针

Holographic optics in planar optical systems for next generation small form factor mixed reality headsets

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Light(Advanced Manufacturing) 2022年第4期3卷 145-175页

作者： bernard C.Kress Maria Pace Microsoft Corp.HoloLens Team 1 Microsoft WayRedmond98052 WA.USA

Helmet Mounted Displays(HMDs),such as in Virtual Reality(VR),Augmented Reality(AR),Mixed reality(MR),and Smart Glasses have the potential to revolutionize the way we live our private and professional lives,as in communicating,working,teaching and learning,shopping and getting *** HMD devices have to satisfy draconian requirements in weight,size,form factor,power,compute,wireless communication and of course display,imaging and sensing *** review in this paper the various optical technologies and architectures that have been developed in the past 10 years to provide adequate solutions for the drastic requirements of consumer HMDs,a market that has yet to become mature in the next years,unlike the existing enterprise and defense markets that have already adopted VR and AR headsets as practical tools to improve greatly effectiveness and *** focus specifically our attention on the optical combiner element,a crucial element in Optical See-Through(OST)HMDs that combines the see-through scene with a world locked digital *** for the technological platform,we chose optical waveguide combiners,although there is also a considerable effort today dedicated to free-space *** and thin optics as in micro-optics,holographics,diffractives,metasurfaces and other nanostructured optical elements are key building blocks to achieve the target form factor.

关键词： Holography Helmet mounted displays Virtual reality Augmented reality Mixed reality