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Transfusion transmitted virus: A review on its molecular characteristics and role in medicine

World Journal of gastroenterology 2006年第32期12卷 5122-5134页

作者： M irshad yK Joshi y Sharma i Dhar Clinical Biochemistry Division Department of Laboratory Medicine All India Institute of Medical SciencesNew Delhi-110029India Department of gastroenterology and Human Nutrition All india institute of Medical Sciences New Delhi-110029India

The present review gives an updated overview of transfusion transmitted virus （TTV）, a novel agent, in relation to its molecular characteristics, epidemiological features, modes of transmission, tissue tropism, pathogenesis, role in various diseases and its eradication from the body. TTV, a DNA virus, is a single stranded, non-enveloped, 3.8 kb long DNA virus with a small and covalently closed circular genome comprising 3852 bases. it was tentatively designated Cirdnoviridae *** genome sequence is heterogeneous and reveals the existence of six different genotypes and several subtypes. TTV has been reported to transmit not only via parenteral routes, but also via alternate routes. This virus has been detected in different non-human primates as well. At present, TTV is detected by polymerase chain reaction （PCR） with no other available diagnostic assays. it shows its presence globally and was detected in high percent populations of healthy persons as well as in various disease groups. initially it was supposed to have strong association with liver disease; however, there is little evidence to show its liver tropism and contribution in causing liver diseases. it shows high prevalence in hemodialysis patients, pointing towards its significance in renal diseases. in addition,TTV is associated with several infectious and non-infectious diseases. Though, its exact pathogenesis is not yet clear, TTV virus possibly resides and multiplies in bone marrow cells and peripheral blood mononuclear cells （PBMCs）. Recently, attempts have been made to eradicate this virus with interferon treatment. More information is still needed to extricate various mysteries related to TTV.

关键词： Transfusion transmitted virus DNA Virus Hepatitis Transfusion

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Relation between etching profile and voltage-current shape of sintered SiC etching by atmospheric pressure plasma

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Plasma Science and Technology 2019年第4期21卷 137-144页

作者： D C SEOK S R yOO K i LEE y S CHOi y H JUNG Plasma Technology Research Center National Fusion Research InstituteGunsan City 54004Republic of Korea

Sintered silicon carbide(SiC)was etched by a dielectric barrier discharge source.A high voltage bipolar pulse was used with helium gas for the plasma *** stable filament plasma was generated and could be used for SiC *** the processing gas(NF3)mixing rate increased,the width and depth of the etching profile became narrower and *** differentiated V-Q Lissajous method was used for measuring the capacitances(Ceq)of the electrode after the plasma turned *** width of the etching profile was proportional to *** the current peak value/smx of the substrate current in creased,the volume removal rate of SiC *** etch depth was proportional to the ratio of/smx to ***,because of the different characteristics of the plasma disks on SiC substrate by the voltage polarity,the etching profile was ***,in high NF3 mixing process,the etching profile became stable and deeper.

关键词： dielectric barrier discharge silicon carbide plasma etching、filament discharge,surface charge

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Experimental and finite element analysis for fracture of coating layer of galvannealed steel sheet

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Transactions of Nonferrous Metals Society of China 2011年第A1期21卷 111-116页

作者： S.i.KiM J.U.HER y.C.JANG y.LEE Sheet Products and Process Research Group POSCO Techology Research Laboratory Department of Mechanical Engineering Chung-Ang University

Mechanical properties of galvannealed (ga) steel sheet used for automotive exposed panel and predicted failure phenomenon of its coating layer were evaluated using finite element method. V-bending test was performed to understand better the fracture of coating layer of ga steel sheet during plastic deformation. yield strength of the coating layer was calculated by using a relative difference between hardness of coating layer measured from the nano-indentation test and that of substrate. To measure shearing strength at the interface between substrate and coating layer, shearing test with two specimens attached by an adhesive was carried out. Using the mechanical properties measured, a series of finite element analyses coupled with a failure model was performed. Results reveal that the fracture of coating layer occurs in an irregular manner at the region where compressive deformation is dominant. Meanwhile, a series of vertical cracks perpendicular to material surface are observed at the tensile stressed-region. it is found that 0.26-0.28 of local equivalent plastic strain exists at the coating and substrate at the beginning of failure. The fracture of coating layer depends on ductility of the coating layer considerably as well.

关键词： galvannealed steel sheet fracture simulation coating layer finite element analysis, failure model

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Combustion modeling in a model combustor

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航空动力学报 2007年第5期22卷 694-703页

作者： L.y.Jiang i.Campbell K.Su institute for Aerospace Research National ResearchCouncil Canada OttawaONK1A 0R6Canada Department of Mechanical Automotiveand Materials EngineeringUniversity of WindsorWindsorONN9B 3P4Canada

The flow-field of a propane-air diffusion flame combustor with interior and exterior conjugate heat transfers was numerically *** obtained from four combustion models,combined with the re-normalization group(RNG) k-ε turbulence model,discrete ordinates radiation model and enhanced wall treatment are presented and *** results are compared with a comprehensive database obtained from a series of experimental *** flow patterns and the recirculation zone length in the combustion chamber are accurately predicted,and the mean axial velocities are in fairly good agreement with the experimental data,particularly at downstream sections for all four combustion *** mean temperature profiles are captured fairly well by the eddy dissipation(EDS),probability density function(PDF),and laminar flamelet combustion ***,the EDS-finite-rate combustion model fails to provide an acceptable temperature *** general,the flamelet model illustrates little superiority over the PDF model,and to some extent the PDF model shows better performance than the EDS model.

关键词：燃烧室燃烧模型扩散火焰热转移

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Nanostructured Catalyst for Fischer-Tropsch Synthesis

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Chinese Journal of Chemistry 2018年第9期36卷 798-808页

作者： wa gao Qingshan Zhu Ding Ma College of Chemistry and Molecular Engineering and College of Engineering Peking University Beijing 100871 China Fritz-Haber-institut der Max-Planck-Gesellschaft Faradayweg 4-6 D-14195 Berlin Germany

Fischer-Tropsch synthesis （FTS） is a heterogeneous catalytic process for the production of fuels or chemicals from synthesis gas （CO ＋ H2）, which can be derived from nonpetroleum feedstocks such as natural gas, coal, or biomass. Co, Ru, Fe and Ni are all active in FTS, but only cheaper Fe and Co based catalysts are used in industry because the price of Ru is relatively high. However, the industrial Fe- and Co-based FTS catalysts normally work at a relatively high temperature range of 493--623 K in order to get a reasonable space time yield. Moreover, the product selectivity of FTS is governed by the law of polymerization, i.e., a so-called Anderson-Schulz-Fiory distribution holds, which restricts its industrial application. in this account, we highlight some of our progress toward the design/fabrication of nanostructured Fe, Co and Ru catalysts to improve FTS activity at the low temperature and to change the product selectivity and confine the product distribution into a certain range.

关键词： catalyst Fischer-Tropsch synthesis nanostructure

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Deep bed filtration model for cake filtration and erosion

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Applied Mathematics and Mechanics(English Edition) 2024年第2期45卷 355-372页

作者： L.i.KUZMiNA y.V.OSiPOV A.R.PESTEREV Department of Applied Mathematics HSE UniversityMoscow 101000Russia Department of Computer Science and Applied Mathematics Moscow State University of Civil EngineeringMoscow 129337Russia

Many phenomena in nature and technology are associated with the filtration of suspensions and colloids in porous media. Two main types of particle deposition,namely, cake filtration at the inlet and deep bed filtration throughout the entire porous medium, are studied by different models. A unified approach for the transport and deposition of particles based on the deep bed filtration model is proposed. A variable suspension flow rate, proportional to the number of free pores at the inlet of the porous medium, is considered. To model cake filtration, this flow rate is introduced into the mass balance equation of deep bed filtration. For the cake filtration without deposit erosion,the suspension flow rate decreases to zero, and the suspension does not penetrate deep into the porous medium. in the case of the cake filtration with erosion, the suspension flow rate is nonzero, and the deposit is distributed throughout the entire porous medium. An exact solution is obtained for a constant filtration function. The method of characteristics is used to construct the asymptotics of the concentration front of suspended and retained particles for a filtration function in a general form. Explicit formulae are obtained for a linear filtration function. The properties of these solutions are studied in detail.

关键词： deep bed filtration cake filtration porous medium particle deposition and erosion analytical solution concentration front

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Tissue inhibitors of metalloproteases strike a nerve

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Neural Regeneration Research 2018年第11期13卷 1890-1892页

作者： veronica i.shubayev alex y.strongin department of anesthesiology university of californiasan diego va san diego healthcare system la jollacausa sanford burnham prebys medical discovery institute la jollacausa

Signals of touch,pressure,pain,temperature,position,and vibration are transmitted from the peripheral nervous system（PNS）to the dorsal horn of the segmental spinal cord via pseudounipolar dorsal root ganglia（DRG）*** information gathering relies on functional integrity of DRG neurons and can be interrupted by PNS injury due to trauma,disease or exposure to drugs, toxins or viral pathogens. Despite the high regenerative capacity of DRG neurons, sensory recovery after PNS injury is often incomplete and severe neuropathic pain may last for years. Although numerous mechanisms of PNS injury have been established, neuropathic pain is refractory to therapy, contributing to the physical and emotional suffering of patients and the enormous economic burden to society.

关键词： TiMPs PNS in Tissue inhibitors of metalloproteases strike a nerve

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Soil Microbial Population in the Vicinity of the Bean Caper(Zygophyllum dumosum)Root Zone in a Desert System

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Pedosphere 2007年第6期17卷 758-765页

作者： i.SHMUELi G.BARNESS y.STEiNBERGER The Mina & Everard Goodman Faculty of Life Sciences Bar-ilan University Ramat-Gan 52900(Israel)

The aim of the current study was to gain a better understanding of the changes in soil microbial biomass and basal respiration dynamics in the vicinity of the bean caper （Zygophyllura duraosura） perennial desert shrub and the inter-shrub sites. Microbial biomasses as well as basal respiration were found to be significantly greater in the soil samples taken beneath the Z. duraosura shrubs than from the inter-shrub sampling sites, with no differences between the two sampling layers （0-10 and 10-20 cm） throughout the study period. However, seasonal changes were observed due to autumn dew formation, which significantly affected microbial biomass and basal respiration in the upper-layer inter-shrub locations. The calculated metabolic coefficient （qCO2） revealed significant differences between the two sampling sites as well as between the two soil layers, elucidating the abiotic effect between the sites throughout the study period. The substrate availability index was found to significantly demonstrate the differences between the two sites, elucidating the significant contribution of Z. duraosura in food source availability and in moderating harsh abiotic components. The importance of basal microbial parameters and the derived indices as tools demonstrated the importance and need for basic knowledge in understanding plant-soil interactions determined by an unpredictable and harsh desert environment.

关键词： basal respiration desert microbial biomass root zone soil

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Asymptotics for filtration of polydisperse suspension with small impurities

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Applied Mathematics and Mechanics(English Edition) 2021年第1期42卷 109-126页

作者： L.i.KUZMiNA y.V.OSiPOV T.N.GORBUNOVA Department of Applied Mathematics National Research University Higher School of EconomicsMoscow 101000Russia Department of Applied Mathematics Moscow State University of Civil Engineering(National Research University)Moscow 129337Russia

A model for deep bed filtration of a polydisperse suspension with small impurities in a porous medium is *** suspended particles move with the same velocity as the carrier water and get blocked in the pore throats due to the size-exclusion mechanism of particle retention.A solution of the model in the form of a traveling wave is *** global exact solution for a multiparticle filtration with one high concentration and several low concentrations of suspended particles is obtained in an explicit *** analytic solutions for a bidisperse suspension with large and small particles are *** profiles of the retained small particles change monotony with *** global asymptotics for the filtration of a polydisperse suspension with small kinetic rates is constructed in the whole filtration zone.

关键词： deep bed filtration suspension colloid porous medium particle size distribution analytical model

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Simplified method for analyzing soil slope deformation under cyclic loading

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第6期14卷 1967-1976页

作者： ga Zhang yaliang wang Fangyue Luo State Key Laboratory of Hydroscience and Engineering Tsinghua UniversityBeijing100084China

Reasonable assessment of slope deformation under cyclic loading is of great significance for securing the safety of slopes. The observations of centrifuge model tests are analyzed on the slope deformation behavior under cyclic loading conditions. The potential slip surface is the key for slope failure and follows two rules:(i) the relative horizontal displacement along the potential slip surface is invariable at an elevation, and(ii) the soil along the slip surface exhibits the same degradation pattern. These rules are effective regardless of the location of the potential slip surface throughout the entire deformation process of a homogeneous slope, ranging from the initial deformation stage to the failure process and to the post-failure stage. A new, simplified method is proposed by deriving the displacement compatibility equation and unified degradation equation according to the fundamental rules. The method has few parameters that can be determined through traditional element tests. The predictions from the proposed method agree with the centrifuge test results with vertical loading and shaking table loading. This result confirms that the proposed method is effective in predicting the full deformation process of slopes under different cyclic loading conditions.

关键词： Soil slope Cyclic load Deformation Centrifuge model test Slice method

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