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Immune response-related genes associated to blocking midgut dengue virus infection in Aedes aegypti strains that differ in susceptibility

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Insect Science 2019年第4期26卷 635-648页

作者： Paola A. Caicedo Idalba Mildred Serrato Shuzhen Sim George Dimopoulos Heather Coatsworth Carl Lowenberger Clara b. Ocampo Centro Internacional de Entrenamiento e Investigaciones Medicas (CIDEIM) Cali Colombia 2W. Harry Feinstone Department of Molecular Microbiology and Immunology Bloomberg School of Public Health Johns Hopkins University Baltimore Maryland USA Department of biological Sciences Simon Fraser University Burnaby Canada

Aedes (Stegomyia) aegypti, the principal global vector of dengue viruses, has difTerences in its susceptibility to dengue virus infection. We compared the global expres? sion of genes in the midguts of Colombian Ae. aegypti dengue-susceptible (Cali-S) and dengue-refractory (Cali-MIb) field derived strains after ingesting either a sugarmeal, a bloodmeal, or a bloodmeal containing dengue virus serotype 2 (DENV-2). Microarraybased transcriptome analysis among treatments indicated a total of 4725 transcripts with differential expression between the two strains. Eleven genes were selected from different functional groups based on their significant up or down expression levels as well as reports in the literature suggesting they are associated with dengue virus elimination. We measured mRNA abundance of these 11 genes at 0, 8, 24, and 36 h postinfection using quantitative real time PCR (qPCR) to confirm the microarray results and assess any temporal patterns. Four genes were selected (Gram-negative binding protein—GNbP [AAEL009176], Niemann Pick Type-C2一NPC2 [AAEL015136], Keratinocyte lectin [AAEL009842], and Cathepsin-b [AAEL007585]) for knockdown experiments using RNA interference (RNAi) methodology to determine the phenotype (DENV-2 susceptible or refractory). Silencing GNbP、Cathepsin-b and Keratinocyte lectin reduced the percentage of mosquitoes with disseminated virus in the Cali-S strain to 8%, 20%, and 12% respectively compared with 96% in the controls. Sile ncing of NPC2 increased the percentage of mosquitos with disseminated virus infections in Cali-MIb to 66% compared with 35% in the controls. This study provides in sight into genes that may contribute to the Cali-S susceptible and Cali-MIb refractory phenotypes in 昇匕 aegypti.

关键词： Aedes aegypti dengue virus innate immune response knockdown microarray vector competence

Identification of four novel DC-SIGN ligands on Mycobacterium bovis bCG

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Protein & Cell 2010年第9期1卷 859-870页

作者： Maria V.Carroll Robert b.Sim Fabiana bigi Anne Jäkel Robin Antrobus Daniel A.Mitchell Department of Pharmacology University of OxfordMansfield RoadOxford OX13QTUK Institute of biotechnology CICVyA-INTALos Reseros y Las Cabañas1712 CastelarArgentina Cambridge Institute of Medical Research Addenbrooke’s HospitalHills RoadCambridge CB20XYUK CSRI-UHCW Walsgrave Campus University of WarwickCoventryCV22DXUK

Dendritic-cell-specific intercellular adhesion molecule-3-grabbing non-integrin(DC-SIGN;CD209)has an important role in mediating adherence of Mycobacteria species,including *** and *** bCG to human dendritic cells and macrophages,in which these bacteria can survive ***-SIGN is a C-type lectin,and interactions with mycobacterial cells are believed to occur via mannosylated structures on the mycobacterial *** studies suggest more varied modes of binding to multiple mycobacterial *** we identify,by affinity chromatography and mass-spectrometry,four novel ligands of *** bCG that bind to *** novel ligands are chaperone protein DnaK,60 kDa chaperonin-1(Cpn60.1),glyceraldehyde-3 phosphate dehydrogenase(GAPDH)and lipoprotein *** published work strongly suggests that these are on the cell *** these ligands,lprG appears to bind DC-SIGN via typical proteinglycan interactions,but DnaK and Cpn60.1 binding do not show evidence of carbohydrate-dependent *** was also identified as a ligand for DC-SIGNR(L-SIGN;CD299)and the *** orthologue of lprG has been found previously to interact with human toll-like receptor ***,these findings offer new targets for combating mycobacterial adhesion and within-host survival,and reinforce the role of DCSIGN as an important host ligand in mycobacterial infection.

关键词： DC-SIGN Mycobacteria lectins

Development on transparent conductive ZnO thin films doped with various impurity elements

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Rare Metals 2011年第2期30卷 175-182页

作者： ZHAO Lin SHAO Guangjie SONG Shitao QIN Xiujuan HAN Sihuizhi School of Environmental and Chemical Engineering Yanshan University Qinhuangdao 066004 China State Key Laboratory of Metastable Materials Science and Technology Yanshan University Qinhuangdao 066004 China Hebei Normal University of Science and Technology Qinhuangdao 066004 China

A general review of recent research progress in fabricating transparent conductive ZnO thin films by means of intentional doping and codoping with In, Ga, A1, Mg, Li, F, H, N, and P, divided into metals and nonmetals, is presented in this article. The main emphasis is placed on introducing and discussing the recent research achievements on the mechanisms of the incorporation of these impurities, and their effects on the electrical and optical properties. Lastly, this article concludes with a summary of the present state of investigations on doping elements in fabricating functional ZnO thin films for photoelectric applications, and with our personal view of the perspective of future studies on doped ZnO thin films.

关键词： thin films conductive films zinc oxide doping electric properties optical properties

INVESTIGATION ON THE DENSITY UNIFORMITY OF PRESSED PARTS bY LOW-VOLTAGE ELECTROMAGNETIC COMPACTION

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Acta Metallurgica Sinica(English Letters) 2004年第6期17卷 805-811页

作者： S.Y.Huang Z.H.Meng Y.C.Li b.Zhang W.Ouyang HarbinInstituteofTechnology Harbin150001China／／WuhanUniversityofTechnologyWuhan430070China WuhanUniversityofTechnology Wuhan430070China

Powder metallurgy is an efficient approach to fabricate varieties of high performance structure materials, function materials and special materials working under limited conditions. Research and development of new efficient technology to form high-density, high-performance and net shape parts is a key to widen application and development of powder materials. Recently, the low-voltage electromagnetic compaction (EMC) has been used by present authors to compacted copper, tin, aluminum powders and the products with 99% relative density have been acquired. In this work, the research has been extended to investigation on the density uniformity of pressed parts. The analysis results show that the density of the part compacted by low-voltage EMC decreases gradually in press direction as static compaction. but it is higher and more homogeneous. The density of the top part increases gradually from the center to the outer, which is just reversal of the bottom part. In some extent, the higher the discharging voltage is, the higher the density is and the more homogeneous the distribution is. In addition, repetitive compaction can improve the density of powder parts and the distribution uniformity.

关键词： powder low-voltage electromagnetic compaction density uniformity density distribution

Impact of mine waters on chemical composition of soil in the Partizansk Coal basin, Russia

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International Soil and Water Conservation Research 2019年第1期7卷 57-63页

作者： Ola Arefieva Alina V.Nazarkina Natalya V.Gruschakova Julia E.Skurikhina Vera b.Kolycheva Far Eastern Federal University 8Sukhanova str.690950VladivostokRussian Federation Institute of biology and Soil Science Far-Eastern BranchRussian Academy of Sciences159Stoletia prospect690022 VladivostokRussian Federation Pacific State Medical University 2Ostryakov Avenue690002VladivostokRussian Federation

Partizansk Coal basin,located in the south of the Russian Far Eastern Region,was intensively mined from 1918 until *** it was mostly explored by underground excavation,the natural landscapes were transformed into anthropogenic *** the mines closed,ground subsidence occurred widely,especially in areas near the waste *** caused water tables to rise to the surface and pollute the *** of the hydrochemical composition of the mine waters were conducted in 2011-2013,and showed low alkalinity and average level of *** can be explained by the fact that while going up through soil mass,the mine waters lost their much of their pollutants due to soil buffering All mine water samples contain thermo-tolerant coliform bacteria *** that indicates a source of fresh fecal *** research indicates increased hydrocarbon ion concentrations in mine waters,especially in autumn,that resulted in accumulation of chromium and copper compounds,which can cause soil pollution.A strong relationship between the chemical composition of the mine waters and soil extracts was found within areas of unregulated groundwater discharge on the *** negative correlation between pH and content of metal compounds including chromium and copper was found at the 'Avangard' mine (r =-0.95);and between alkalinity and chromium content at the 'Glubokaya' mine (r =-0.94).

关键词： Mine waters Soil solution Chemical composition Abandoned coal mines bacteriological contamination of water

Kinetics and mechanisms of the catalytic thermal cracking of asphaltenes adsorbed on supported nanoparticles

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Petroleum Science 2016年第3期13卷 561-571页

作者： Tatiana Montoya blanca L.Argel Nashaat N.Nassar Camilo A.Franco Farid b.Cortés Department of Chemical and Petroleum Engineering University of Calgary 2500 University Drive NW CalgaryAB Canada Grupo de Investigacion Fenomenos de Superficie-Michael Polanyi Facultad de Minas Universidad Nacional de Colombia Sede Medellin Medellin Colombia Grupo de Investigacion en Yacimientos de Hidrocarburos Facultad de Minas Universidad Nacional de Colombia Sede Medellfn Kra 80 No. 65-223 Medellfn Colombia

The production of heavy and extra-heavy oil is challenging because of the rheological properties that crude oil presents due to its high asphaltene *** upgrading and recovery processes of these unconventional oils are typically water and energy intensive,which makes such processes costly and environmentally *** catalysts could be used to enhance the upgrading and recovery of heavy oil under both in situ and ex situ *** this study,the effect of the Ni-Pd nanocatalysts supported on fumed silica nanoparticles on post-adsorption catalytic thermal cracking of n-C_7 asphaltenes was investigated using a thermogravimetric analyzer coupled with *** performance of catalytic thermal cracking of n-C_7asphaltenes in the presence of NiO and PdO supported on fumed silica nanoparticles was better than on the fumed silica support *** a fixed amount of adsorbed n-C_7asphaltenes（0.2 mg/m～2）,bimetallic nanoparticles showed better catalytic behavior than monometallic nanoparticles,confirming their synergistic *** corrected OzawaFlynn-Wall equation（OFW） was used to estimate the effective activation energies of the catalytic *** mechanism function,kinetic parameters,and transition state thermodynamic functions for the thermal cracking process of n-C_7 asphaltenes in the presence and absence of nanoparticles are investigated.

关键词： Catalytic thermal cracking Adsorption Nanoparticles SHS n-C7 asphaltene

Effects of lime addition on geotechnical properties of sedimentary soil in Curitiba,brazil

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第1期10卷 188-194页

作者： Jair A.baldovino Eclesielter b.Moreira Wagner Teixeira Ronaldo L.S.Izzo Juliana L.Rose Department of Civil Construction Federal University of Technology-Paraná Campus Curitiba

The soil of the Guabirotuba geological formation（Paraná basin, brazil） has physico-mechanical properties which are not suitable for its utilization in pavement construction, in protection of hillsides and slopes, or as shallow foundation support. Treatment of this soil by lime addition would improve its usability. The present context intends to determine the ratio between the splitting tensile strength（q;）and the unconfined compressive strength（q;） of clayey soil in the metropolitan region of Curitiba City,which has been treated with different lime contents and curing times. The control parameters evaluated include lime content（L）, curing time（t）, moisture content（w）, and ratio of porosity to volumetric lime content（η/L;）. It was observed that the q;/q;ratio is between 0.17 and 0.2 in relation to the curing time,and an exponential relation exists between them. Meanwhile, the unconfined compressive strength of lime-treated soil was found to be approximately four times the initial value.

关键词： Clayey soil stabilization Soil strength Lime-soil mixture Curing time

In situ selective laser gas nitriding for composite TiN/Ti-6Al-4V fabrication via laser powder bed fusion

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Journal of Materials Science & Technology 2020年第10期42卷 98-107页

作者： P.A.Morton H.C.Taylor L.E.Murr O.G.Delgado C.A.Terrazas R.b.Wicker W.M.Keck Center for 3D Innovation The University of Texas at El PasoEl PasoTX79968USA Department of Mechanical Engineering The University of Texas at El PasoTX 79968USA Department of Metallurgical Materials and Biomedical EngineeringThe University of Texas at El PasoTX 79968USA

Laser-assisted gas nitriding of selective Ti-6Al-4V surfaces has been achieved during laser powder bed fusion fabrication by exchanging the argon build gas environment with *** variation of processing parameters allowed microdendritic Ti N surface coatings to be formed having thicknesses ranging from a few tens of microns to several hundred microns,with TiN dendrite microstructure volume fractions ranging from 0.6 to 0.75;and corresponding Vickers microindentation hardness values ranging from^7.5 GPa–9.5 *** TiN hard layers ranging from 50μm to 150μm thick were also fabricated in the laser-beam additively manufactured Ti-6Al-4V alloy producing prototype,hybrid,planar composites having alternating,ductile Ti-6Al-4V layers with a hardness of^4.5 GPa and a stiff,TiN layer with a hardness of^8.5 *** results demonstrate prospects for fabricating novel,additively manufactured components having selective,hard,wear and corrosion resistant coatings along with periodic,planar or complex metal matrix composite regimes exhibiting superior toughness and related mechanical properties.

关键词： Ti-6Al-4V TiN ceramic coatings and embedded layers Dendritic microstructures Selective laser melting Additive manufacturing Metal matrix composites Selective nitriding

Evaluating instrumented Charpy impact strain signals using curve fitting equations

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Journal of Central South University 2014年第2期21卷 600-609页

作者： M.b.Ali S.Abdullah M.Z.Nuawi A.K.Ariffin Z.M.Nopiah Department of Mechanical and Materials Engineering Faculty of Engineering and Built EnvironmentUniversiti Kebangsaan Malaysia Department of Structure and Material Faculty of Mechanical EngineeringUniversiti Teknikal Malaysia Melaka

An effective and simple way to develop equations from impact strain signals was *** research has been performed in this area,but this equation is very important for evaluating input signals in finite element analysis impact tests and for obtaining additional information on material deformation and fracture processes under impact *** this purpose,dynamic impact responses were examined through signals obtained from a strain gauge installed on an impact striker connected to a data acquisition *** 6061-T6 was used to extract strain responses on the striker during Charpy impact *** analysis was performed using the I-kaz method,and curve fitting equations based on the equation for vibration response under a non-periodic force were used to evaluate the Charpy impact *** I-kaz coefficients and curve fitting equations were then compared and discussed with related parameters,such as velocities and *** and thickness were found to be related to the strain signal patterns,curve fitting equations and I-kaz *** equations developed using this method had R2 values greater than 97.7%.Finally,the constructed equations were determined to be suitable for evaluating Charpy impact strain signal patterns and obtaining additional information on fracture processes under impact loading.

关键词：曲线拟合方程应变信号评估摆锤式仪器数据采集系统夏比冲击试验附加信息