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Epidemiology,surveillance and control of methicillin-resistant Staphylococcus aureus:an Overview

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Asian Pacific Journal of Tropical Medicine 2008年第1期1卷 50-55页

作者： Li f DeWolfe Miller f School of Social Work University of HawaiiHonoluluHI 96822USA John A.Burns School of Medicine University of HawaiiHonoluluH196822USA

Staphylococcus aureus(***) is one of the most common human pathogens,causing a wide range of afflictions from minor infections of the skin to serious wound infections,bacteraemia,pneumonia and endocarditis. Methicillin,the first semisynthetic derivative of penicillin,was a new hope to treat penicillin resistant *** in the early ***,only one year after its introduction,the first methicillin-resistant *** (MRSA) strains were *** is no golden rule in the control of ***,using surveillance cultures of patients and healthcare personnel,strictly enforced contact precautions,and judicious use of broad-spectrum antibiotics have helped several countries,including finland,Denmark,and the Netherlands to keep MRSA at a very low ***,countries including China,Japan,US,Italy,Greece,UK, where stringent counter-measure were not able to be installed,MRSA have become *** of MRSA in those countries were obliged to concentrate available resources to prevent MRSA infections only at patients at high risk of serious morbidity and mortality.

关键词： Staphylococcus aureus methicillin surveillance

Toward the Design of Multi Asymmetric Surface Dielectric Barrier Discharge (ASDBD) Actuators

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Plasma Science and Technology 2015年第1期17卷 56-63页

作者： Massiel ZADEH V.ROHANI f.CAUNEAU f.fABRY L.fULCHERI Centre for Processes Renewable Energies and Energy Systems-PERSEE- MINES ParisTech

This paper investigates the electrical and mechanical behaviors of a single-ASDBD actuator and a two-ASDBD one supplied in sinusoidal mode（1-10 kHz）.The main objective of our research is to determine the optimum frequency values for the function of these actuators with a given power *** this purpose,we determine the electrical power density input to the actuators versus frequency through two methods：i） a semi-theoretical method,based on an impedance calculation,and ii） an experimental method,based on direct electrical *** methods show that the addition of a second ASDBD changes the resonance frequency value of the actuator by moving it towards low *** characterizing the aerodynamic mobile layer structure induced by the single-ASDBD actuator,we analyze experimentally the mechanical response of a two-ASDBD actuator as a function of the inter-ASDBD *** experiments demonstrate that the induced electric wind velocity and the electro-mechanical yield of a twoASDBD actuator reach a maximum value for an optimum inter-ASDBD distance,which is a useful value for the design of highly efficient multi-ASDBD actuators.

关键词： ASDBD actuator resonance frequency electro-mechanical yield

Interactive data styling and multifocal visualization for a multigrid web-based Digital Earth

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International Journal of Digital Earth 2021年第3期14卷 288-310页

作者： M.J.Sherlock M.Hasan f.f.Samavati Department of Computer Science University of CalgaryCalgaryCanada

Globe-based Digital Earth(DE)is a promising system that uses 3D models of the Earth for integration,organization,processing,and visualization of vast multiscale geospatial *** growing size and scale of geospatial datasets present significant obstacles to interactive viewing and meaningful visualizations of these DE *** address these challenges,we present a novel web-based multiresolution DE system using a hierarchical discretization of the globe on both server and client *** presented web-based system makes use of a novel data encoding technique for rendering large multiscale geospatial datasets,with the additional capability of displaying multiple simultaneous *** the data needed for the current views and scales are encoded and *** leverage the power of GPU acceleration on the client-side to perform real-time data rendering and dynamic *** rendering of multiple views allows us to support multilevel focus+context visualization,an effective approach to navigate through large multiscale global *** client–server interaction as well as the data encoding,rendering,styling,and visualization techniques utilized by our presented system contribute toward making DE more accessible and informative.

关键词： Digital Earth Discrete Global Grid System data integration data fusion multilevel focus+context visualization spatial resolution context awareness

Topsoil as Affected by Dung Deposition Under Resting Places of Red Howler Monkey (Alouatta seniculus)

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Pedosphere 2008年第6期18卷 691-698页

作者： S. POUVELLE f. fEER J. f. PONGE Musum National d'Histoire Naturelle CNRS UMR 7179 4 avenue du Petit-Chateau

The short-term influence of dung deposition and the further redistribution of dung by dung beetles were studied under a resting place of the red howler monkey （Alouatta seniculus） living in tropical ralnforests of South America. Monkey dung was experimentally clumped on the field in a place used by troops of howler monkeys for resting in the Nouragues Reserve Station, french Guiana. Dung-treated plots were sampled serially over three weeks and compared with controls located in their immediate vicinity. The composition of the soil matrix （top 10 cm） was studied in successive microlayers using an optical method. Under the influence of dung beetle activity, the topsoil became more homogeneous by losing its litter, its content in earthworm faeces increased in the course of time, and surface mineral deposits were penetrated by roots. The results were interpreted in the light of present knowledge on the effects of soil animal activity on plant growth and survival of seedlings.

关键词： dung beetle activity earthworm faeces roots tropical ralnforests

TESTING INEQUALITY CONSTRAINTS IN A LINEAR REGRESSION MODEL WITH SPHERICALLY SYMMETRIC DISTURBANCES

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Journal of Systems Science & Complexity 2014年第6期27卷 1204-1212页

作者： ZHU Rong ZHOU Sherry Z f Academy of Mathematics and Systems Science Chinese Academy of Sciences Department of Management Sciences City University of Hong Kong

This paper develops a Wald statistic for testing the validity of multivariate inequality constraints in linear regression models with spherically symmetric disturbances,and derive the distributions of the test statistic under null and nonnull *** power of the test is then *** evaluations are also carried out to examine the power performances of the test for the case in which errors follow a multivariate student-t(Mt) distribution.

关键词： Inequality constraint spherically symmetric distribution Wald test.

Ultrahigh temporal contrast performance of the PHELIX petawatt facility

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High Power Laser Science and Engineering 2016年第4期4卷 1-8页

作者： V.Bagnoud f.Wagner Plasma physics dep. GSI Helmholtzzentrum für Schwerionenforschung GmbH Helmholtz Institute Jena

We report on the temporal contrast performance of the PHELIX facility in view of the requirements imposed by solidtarget interaction experiments. The requirement analysis for the nanosecond and picosecond temporal contrast is derived from empirical data and simple theoretical modeling, while the realization shows that using an ultrafast optical parametric amplifier and plasma mirrors enables meeting this specification.

关键词： amplified spontaneous emission chirped-pulse amplification optical parametric amplification temporal contrast

finite element simulation of elastoplastic fieldnear crack tips and results for a central crackedplate of le-lhp material under tension

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Acta Mechanica Sinica 2019年第4期35卷 828-838页

作者： X. Ji f. Zhu School of Aerospace Engineering and Applied Mechanics Tongji University Shanghai 200092 China

The elastoplastic field near crack tips is investigated through finite element simulation.A refined mesh model near the crack tip is proposed. In the mesh refining area, element size continuously varies from the nanometer scale to themicrometer scale and the millimeter scale. Graphics of the plastic zone, the crack tip blunting, and the deformed crack tip elements are given in the *** on the curves of stress and plastic strain, closely near the crack tip, the stresssingularity index and the stress intensity factor,as well as the plastic strain singularity index and the plastic strain intensity factor are *** and plastic strainsingular index vary with the load, while the dimensions of the stress and the plastic strain intensity factorsdependon the stress and the plastic strain singularity index, respectively. The singular field near the elastoplastic crack tip is characterized by the stress singularity index and the stress intensity factor, or alternativelythe plastic strain singularity index and the plastic strain *** the end of the paper, following Irwin’s concept of fracture mechanics,σδKσδKcriterion andεδQεδQcriterion are ***, crack tip angle criterion is also presented.

关键词： Crack fracture mechanics Elastoplasticity finite element method Geometry Nonlinearity

Modified Burzynski criterion with non-associated flow rule for anisotropic asymmetric metals in plane stress problems

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Applied Mathematics and Mechanics(English Edition) 2015年第3期36卷 303-318页

作者： f.MOAYYEDIAN M.KADKHODAYAN Department of Mechanical Engineering Ferdowsi University of Mashhad

The Burzynski criterion is developed for anisotropic asymmetric metals with the non-associated flow rule （NAfR） for plane stress problems. The presented pressure depending on the yield criterion can be calibrated with ten experimental data, i.e., the tensile yield stresses at 0°, 45°, and 90°, the compressive yield stresses at 0°, 15°, 30°, 45°, 75°, and 90° from the rolling direction, and the biaxial tensile yield stress. The corresponding pressure independent plastic potential function can be calibrated with six experimental data, i.e., the tensile R-values at 0°, 15°, 45°, 75°, and 90° from the rolling direction and the tensile biaxial R-value. The downhill simplex method is used to solve these ten and six high nonlinear equations for the yield and plastic potential functions, respectively. The results show that the presented new criterion is appropriate for anisotropic asymmetric metals.

关键词： modified Burzynski criterion pressure dependent asymmetric metal down-hill simplex method non-associated flow rule (NAfR)

Nanoparticle migration effects on fully developed forced convection of TiO2-water nanofluid in a parallel plate microchannel

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Particuology 2016年第1期14卷 96-107页

作者： f. Hedayati G. Domairry Young Researchers and Elite Club Neyshabur Branch Islamic Azad University Neyshabur Iran Mechanical Engineering Department Babol University of Technology Babol lran

This study considers the forced convection of laminar TiO2-water nanofluid flow in a parallel plate microchannel. The small length scale associated with microchannels dictates the use of slip condition at the fuid-solid interface. The modified Buongiorno model was employed for the nanofiuid to fully account for the effects of non-uniform viscosity and thermal conductivity. The partial differential equa- tions associated with conservation laws were reduced to two-point ordinary boundary value differential equations before being numerically solved. Considering Brownian motion and thermophoresis, the effects of nanoparticle transport on concentration, velocity, and temperature profiles were analyzed for three different values of wall heat flux. To assess the efficiency of adding nanoparticles, the ratios of the pres- sure drop and the heat transfer coefficient of the nanofluid to that of the base fluid were studied in detail. from analyzing different heat flux ratios, one-sided heating was found to be most efficient at enhancing the heat transfer rate in the microchannel. Additionally, in the presence of the slip velocity, the increase in the value of the heat transfer coefficient for the nanofluid was smaller than that for the base fluid.

关键词： Nanofluid Microchannel Nanoparticles migration Slip velocity Brownian motion Thermophoresis