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Evolutionary Implication of Outer Membrane Lipoprotein-Encoding Genes ompL1,lipL32 and lipL41 of Pathogenic Leptospira Species

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Genomics, Proteomics & Bioinformatics 2009年第3期7卷 96-106页

作者： k. Vedhagiri k. Natarajaseenivasan P. Chellapandi S.G. Prabhakaran Joseph Selvin S. Sharma P. Vijayachari Division of Medical Microbiology Department of MicrobiologySchool of Life Sciences Bharathidasan UniversityTiruchirappalli 620024TamilnaduIndia Department of Bioinformatics School of Life SciencesBharathidasan UniversityTiruchirappalli 620024TamilnaduIndia Regional Medical Research Centre(RMRC) Indian Council of Medical Research/WHO Collaborative Centre for DiagnosisResearchReference and Training in LeptospirosisPort Blair 744101Andaman and Nicobar IslandsIndia

Leptospirosis is recognized as the most widespread zoonosis with a global distribution. In this study, the antigenic variation in Leptospira interrogans and Leptospira borgpetersenii isolated from human urine and field rat kidney was preliminarily confirmed by microscopic agglutination test using monoclonal antibodies, and was further subjected to amplification and identification of outer membrane lipoproreins with structural gene variation. Sequence similarity analysis revealed that these protein sequences, namely OmpL1, LipL32 and LipL41, showed no more homologies to outer membrane lipoproteins of non-pathogenic Leptospira and other closely related Spirochetes, but showed a strong identity within L. interrogans, suggesting intra-specific phylogenetic lineages that might be originated from a common pathogenic leptospiral origin. Moreover, the ompL1 gene showed more antigenic variation than lipL32 and lipL41 due to less conservation in secondary structural evolution within closely related species. Phylogenetically, ompL1 and lipL4l of these strains gave a considerable proximity to L. weilii and L. santaro- sai. The ompI,1 gene of L. interrogans clustered distinctly from other pathogenic and non-pathogenic leptospiral species. The diversity of ompL genes has been an- alyzed and it envisaged that sequence-specific variations at antigenic determinant sites would result in slow evolutionary changes along with new serovar origination within closely related species. Thus, a crucial work on effective recombinant vaccine development and engineered antibodies will hopefully meet to solve the therapeutic challenges.

关键词： Leptospiru ompL1 lipL32 lipL41 phylogeny antigenic variation

Mineral Composition of Loess-Paleosol Samplesfrom the Loess Plateau of China and Its Environmental Significance

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Chinese Journal Of Geochemistry 1994年第1期13卷 61-72页

作者：郑洪汉 B.k.G.THENG 等 GuangzhouInstituteofNewTechniquesforGeology ChineseAcademyofSciencesWushanGuangzhou510640 LandcareR

34 samples of loess-paleosol from the Luochuan and kifeng sections in the Loess Plateau, north-ern China were separated into sand, silt and clay fractions and analyzed for their mineral composi -tions. The results indicate that there is almost no difference between loess and paleosol in mineralcomposition. Major mineral species are quartz, mica, feIdspar and chlorite, accounhng for about88-92% of the total, other minerals are kandite, smectite, vermiculite and a few heavy minerals. Thecalcite, magnetite and hematite were not taken into consideration because of their removal in the pro-cess of sample preparation. The main difference with respect to the mineral composition of samplescollected from different sections and different stratigraphic leveIs lies in the amount and grain sise ofminerals hosted. Comparisons between the Luochuan section and the kifeng section, between paleosoland loess and between the upper part and the lower part of some paleosol layers show that the for-mers contain less feldspar but more mica and vermiculite and are finer in grain sise, indicahng theco-occurrence of both biochemical weathering process responsible for mineral change and physicalweathering process leading to grain-stie change during the soiI-forming processes. This result favourssuch an explanation of the soi1-forming mechanism that loess deposition and paleosol developmentoccurred synchronously, though the rate of soil formation was greater than that of loess deposition,thus leading to soil development.

关键词：古土壤黄土高原成壤过程矿物组成环境标志黄土

Integrated modeling of fracturing-flowback-production dynamics and calibration on field data:Optimum well startup scenarios

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Petroleum Science 2023年第4期20卷 2202-2231页

作者： S.A.Boronin k.I.Tolmacheva I.A.Garagash I.R.Abdrakhmanov G.Yu Fisher A.L.Vainshtein P.k.kabanova E.V.Shel G.V.Paderin A.A.Osiptsov Skolkovo Institute of Science and Technology(Skoltech) Russia LLC Gazpromneft Science and Technology Center Russia The Schmidt Institute of Physics of the Earth of the Russian Academy of Sciences MoscowRussia

We aim at the development of a general modelling workflow for design and optimization of the well flowback and startup operation on hydraulically fractured *** flowback model developed earlier by the authors is extended to take into account several new fluid mechanics factors accompanying flowback,namely,viscoplastic rheology of unbroken cross-linked gel and coupled“fracture-reservoir”numerical submodel for influx from rock *** also developed models and implemented new geomechanical factors,namely,(i)fracture closure in gaps between proppant pillars and in proppant-free cavity in the vicinity of the well taking into account formation creep;(ii)propagation of plastic deformations due to tensile rock failure from the fracture face into the fluid-saturated *** carried out parametric calculations to study the dynamics of fracture conductivity during flowback and its effect on well production for the set of parameters typical of oil wells in Achimov formation of Western Siberia,*** first set of calculations is carried out using the flowback model in the reservoir linear flow *** is obtained that the typical length of hydraulic fracture zone,in which tensile rock failure at the fracture walls occurs,is *** the range of rock permeability in between 0.01 mD and 1 D,we studied the effect of non-dimensional governing parameters as well as bottomhole pressure drop dynamics on oil *** obtained a map of pressure drop regimes(fast,moderate or slow)leading to maximum cumulative oil *** second set of parametric calculations is carried out using integrated well production modelling workflow,in which the flowback model acts as a missing link in between hydraulic fracturing and reservoir commercial *** evaluated quantitatively effects of initial fracture aperture,proppant diameter,yield stress of fracturing fluid,pressure drop rate and proppant material type(ceramic and sand)on long-term well product

关键词： Fracture cleanup Flowback Tensile rock failure Fracture closure Proppant embedment Proppant pack compaction

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GPS时钟在线监测与修正方法

中国电机工程学报 2002年第12期22卷 41-46页

作者：曾祥君尹项根 k.k.Li W.L.Chan 长沙电力学院湖南长沙410077 华中科技大学电气与电子工程学院湖北武汉430074 香港理工大学电机系

受干扰、卫星失锁等因素的影响,全球定位系统(GPS)时钟难以满足高可靠性同步控制领域的要求。文中根据高精度晶振与GPS时钟精度互补的特点,采用高精度晶振对GPS时钟进行监测,建立了最小二乘估计模型,估计出GPS时钟的方差及晶振的累计误... 详细信息

受干扰、卫星失锁等因素的影响,全球定位系统(GPS)时钟难以满足高可靠性同步控制领域的要求。文中根据高精度晶振与GPS时钟精度互补的特点,采用高精度晶振对GPS时钟进行监测,建立了最小二乘估计模型,估计出GPS时钟的方差及晶振的累计误差,给出了GPS时钟误差的在线修正方法,研制出了具有较高性能价格比的高精度时钟发生装置,并成功地应用于电力系统继电保护与控制。

关键词： GPS 时钟在线监测修正方法全球定位系统电力系统继电保护

ON DISTRIBUTIVE MODULES AND LOCALLY DISTRIBUTIVE RINGS

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Chinese Annals of Mathematics,Series B 1991年第1期12卷 26-32页

作者： k.R.Fuller 薛卫民 Department of Mathematics University of Iowalowa CityIowaU.S.A. Department of Mathematics Fujian Normal UniversityFuzhouFujianChina.

Distributive modules over artinian rings are characterized via module diagrams,andit is shown that a left artinian ring is(two-sided)locally distributive in case its leftindecomposable injective modules and projective modules are *** latter resultis used to show that a locally distributive artinian ring and the endomorphism ring of itsminimal cogenerator have identical diagrams.

关键词： projective identical sided latter rings locally maximal 任尹 algebra indeed

Reducing force transmissibility in multiple degrees of freedom structures through anti-symmetric nonlinear viscous damping

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Acta Mechanica Sinica 2012年第5期28卷 1436-1448页

作者： Z.-k.Peng Z.-Q.Lang G.Meng S.A.Billings State key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University Department of Automatic Control and Systems Engineering University of Sheffield

In the present study, the Volterra series theory is adopted to theoretically investigate the force transmissibility of multiple degrees of freedom （MDOF） structures, in which an isolator with nonlinear anti-symmetric viscous damping is assembled. The results reveal that the anti-symmetric nonlinear viscous damping can significantly reduce the force trans- missibility over all resonance regions for MDOF structures with little effect on the transmissibility over non-resonant and isolation regions. The results indicate that the vibration isolators with an anti-symmetric damping characteristic have great potential to solve the dilemma occurring in the design of linear viscously damped vibration isolators where an increase of the damping level reduces the force transmissibility over resonant frequencies but increases the transmissibility over non-resonant frequency regions. This work is an extension of a previous study in which MDOF structures installed on the mount through an isolator with cubic nonlinear damping are considered. The theoretical analysis results are also verified by simulation studies.

关键词： Nonlinear viscous damping Force transmissibility - Vibration isolation Volterra series

Rare earth-doped mixed Ni-Cu-Zn ferrites as an effective photocatalytic agent for active degradation of Rhodamine B dye

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Journal of Rare Earths 2024年第3期42卷 488-496,I0003页

作者： Swapnil A.Jadhav Sandeep B.Somvanshi Sudarshan S.Gawali kranti Zakde k.M.Jadhav Department of Physics Dr.Babasaheb Ambedkar Marathwada UniversityAurangabad431004MaharashtraIndia School of Materials Engineering Purdue UniversityWest Lafayette 47906USA University Department of Basic and Applied Sciences MGM UniversityAurangabad431003MaharashtraIndia

In this study, a series of Gd^(3+)-doped mixed Ni-Cu-Zn ferrites with composition of Zn_(0.5)Ni_(0.3)Cu_(0.2)Fe_(2-x)Gd_(x)O_(4)(x = 0, 0.025, 0.05, 0.075, 0.1) was prepared using self-ignition sol-gel method. The prepared nanoparticles with an average size ranging from 22 to 26 nm show a single-phase cubic structure belonging to the spinel matrix. A rise in the Gd^(3+)concentration leads to an increase in crystallite size and lattice parameter. In Fourier transform infrared spectra, two main absorption bands belonging to the spinel structure are observed. The high-frequency bands(v_(1)) represent the tetrahedral complex, while the lowfrequency bands(v_(2)) signify the octahedral complex. The optical bandgap of the nanoferrites is found within the range of 2.91 to 2.41 eV, depending on their size. The magnetic characteristics of the material,such as saturation magnetization and coercivity are significantly altered with the concentration of Gd^(3+)in the solution. Using Rhodamine B(RhB) as a model organic pollutant, an in-depth investigation of the photocatalytic activity of the compounds was carried out. The present outcomes show that adding an adequate amount of Gd^(3+)significantly enhances the number of hydroxyl radicals produced by the ferrite,in turn, increasing the photocatalytic activity of the material. Mechanism elucidated by scavenger studies reveals that ·OH and holes are the primary reactive radicals responsible for the degradation *** photocatalysts show an insignificant performance loss in five consecutive cycles. Thus, it is concluded that these photocatalysts are highly suitable for the remediation of dye-contaminated wastewater.

关键词： Gd^(3+)substitution Spinel ferrite Structural properties Magnetic properties Photocatalysis Rare earths

Dynamic microstructure evolution and mechanical properties of dilute Mg-Al-Ca-Mn alloy during hot rolling

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Journal of Materials Science & Technology 2022年第34期129卷 1-14页

作者： Shiwei Xu Congcong Zhu Zhanhong Lin Chen Jin S.kamado k.Oh-ishi Yun Qin College of Materials Science and Engineering Hunan UniversityChangsha 410082China State key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan UniversityChangsha 410082China Qinghai Salt Lake Teli Magnesium Co.Ltd. Xining 810000China Department of Mechanical Engineering Nagaoka University of TechnologyNagaoka 940-2188Japan Toyota Central R&D Labs. Inc.41-1 YokomichiNagakuteAichi 480-1192Japan Research Institute(R&D Centre) Baowu Steel Group CorporationShanghai 201900China

The dynamic microstructure and texture of dilute Mg-0.50Al-0.71Ca-0.33Mn(wt.%) during hot rolling at two slab temperatures were investigated by electron backscattered diffraction(EBSD) and high resolution transmission electron microscopy(HRTEM). The results show that the development of the rolling microstructures is to first form {10–12} extension twins in the original grains, thereby forming the extension-twinned regions, and then to further form {10–11}-{10–12} double twins and kinks in the extension-twinned regions, and finally to form continuous dynamic recrystallized(continuous DRXed)grains in the double twins and the cross parts of the shear-deformed coarse extension-twinned *** extension twins, double twins and kinks show a decisive effect on the formation of rolling *** number of {10–11}-{10–12} double twins and resultant the continuous DRX process are strongly affected by the rolling slab temperature and the reduction thickness per pass. By optimizing the rolling conditions, texture and microstructures of the multi-pass rolled Mg-Al-Ca-Mn alloy sheets are successfully modified. Although the total alloy content is only 1.5 wt.%, these Mg-Al-Ca-Mn alloy sheets show much higher strength than the commercial Mg-3Al-1 Zn(wt.%)(AZ31B) sheet.

关键词： Mg-Al-Ca-Mn alloy Hot rolling Dynamic recrystallization Texture control Mechanical properties

Numerical simulation of warhead transportation

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Defence Technology（防务技术） 2021年第2期17卷 478-494页

作者： G.Martynenko k.Avramov V.Martynenko M.Chernobryvko A.Tonkonozhenko V.kozharin Podgorny Institute for Mechanical Engineering National Academy of Science of UkraineDepartment of Vibrations2/10 Pozharskogo St.61046 KharkivUkraine National Technical University“kharkiv Polytechnic Institute” 2 Kyrpychova Str61002 KharkivUkraine Yangel Yuzhnoye State Design Office DniproUkraine kharkiv National University of Radio Electronics Department of Technical SystemsKharkovUkraine

The new numerical approach for analysis of the warhead transportations is *** approach allows to control the warhead operability before its experimental *** approach is implemented by the adequate models for the software *** of the loads at land operations and transportations of the warhead by natural roads,water and aviation allows to obtain the maximal values of loads,which are used in numerical simulations of the *** loads give an opportunity to analyze the operability and the fatigue strength of the cartridge *** numerical simulations of the attachments of the warhead combat elements are performed on the basis of the suggested *** data of the numerical simulations verifies the operability of the fastener system of the warhead combat elements.

关键词： Cartridge warhead Land operation Finite element simulation Operability condition