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解释结核分枝杆菌DNA指纹簇

国际结核病与肺部疾病杂志 2000年第1期3卷 4-9页

作者： j.r.glynn j.Bauer A.S.deBoer M.W.Borgdorff P.E.M.Fine P.Godfrey-Faussett E.Vynnycky 丁北川 Department of Infectious and Tropical Diseases London School of Hygiene and Tropical Medicine Keppel St LondonUK Department of Mycobacteriology Statens Serum Institut Copenhagen Denmark National Institute of Public Health and the Environment Bilthoven royal Netherlands Tuberculosis Association The Hague The Netherlands Department of Infectious and Tropical Diseases London School of Hygiene and Tropical Medicine Keppel St London UK European Concerted Actionon Molecular Epidemiology Control of Tuberculosis

许多研究已在其结核分枝杆菌分离株共享DNA指纹的基础上定义了患者簇。成簇相当于最近的传播,并且对伴随结核分枝杆菌正在高度传播人群亚组来说,与成簇有关的因素已作为指标被找出。在进行和解释这些研究中值得考虑的提醒应予以注意。例... 详细信息

许多研究已在其结核分枝杆菌分离株共享DNA指纹的基础上定义了患者簇。成簇相当于最近的传播,并且对伴随结核分枝杆菌正在高度传播人群亚组来说,与成簇有关的因素已作为指标被找出。在进行和解释这些研究中值得考虑的提醒应予以注意。例如,根据标志物的稳定性和长时间在人群中的菌株数量,某些并非近期传播的原因使菌株组可能完全相同。如果病例对特定人群是新移民或在研究中不是所有人群中的病例都被包括的话,确定由近期传播引发的病例可能不作为成簇被见到。所见的成簇数量将根据研究持续的时间。在研究的设计、所包括病例的比例、补充和所使用成簇的界定上,研究应给出精确的资料。成簇的数据应至少被年龄、性别和移民状况分开。为了最大的获得信息,研究应涉及一个人群中所有病例的高比例、与传统的流行病学接触调查结合进行(如果可能的话)、并且提供人群中结核病发病资料和患者的年龄、性别、人类免疫缺损病毒状况、耐药性及社会和种族组资料。关键词:结核病;分子流行病学;DNA指纹;rFLP;传播;

关键词：结核分枝杆菌 tuberculosis DNA指纹 Mycobacterium 成簇流行病学 Tropic 菌株结核病时间窗口

在非洲农村将接触结核病作为发生结核病的一个危险因素的评价与评估

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国际结核病与肺部疾病杂志 2008年第4期3卷 158-163页

作者： A.C.Crampin S.Floyd B.M.Ngwira V.Mwinuka j.N.Mwaungulu K.Branson P.E.M.Fine j.r.glynn 张晓进何广学 Karonga Prevention Study ChilumbaMalawi London School of Hygiene and Tropical Medicine LondonUK

背景:马拉维的一个农村地区目的:确定非精确回顾法对估算确诊结核病病例接触者发生结核病的影响。方法:对实验室确诊的结核病例与社区对照组进行病例对照研究,对一个结核病数据库内准备访谈的结核病患者的亲属、家庭成员和地区接触者进... 详细信息

背景:马拉维的一个农村地区目的:确定非精确回顾法对估算确诊结核病病例接触者发生结核病的影响。方法:对实验室确诊的结核病例与社区对照组进行病例对照研究,对一个结核病数据库内准备访谈的结核病患者的亲属、家庭成员和地区接触者进行比较。估算有接触史是患结核病的一个危险因素并确定接触者的有关的因素。结果:95%的被确定的接触者是已知的结核病病例。访谈的接触者占确定的接触者的比例为75%,病例组和对照组相似。先前有接触史在病例组是对照组的2倍。数据库信息的加入并没有影响比值比,但是增加了有接触史者患病的比例。远期发生的病例多为涂片阳性、男性和HIV阴性结核病患者。与涂片阳性患者有近期接触的结核病患者占12.5%。结论:确定的接触者报告显示较小的回顾偏倚,可以估算结核病接触者与结核病的相对危险度。被确定为接触者的HIV阳性病例较低可能反映降低了传染力。

关键词：结核接触者马拉维流行病学 hiv

非洲农村某高HIV流行地区利用两涂片与三涂片法诊断培阳肺结核病人的效果比较

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国际结核病与肺部疾病杂志 2002年第4期 142-146页

作者： A.C.Crampin S.Floyd F.Mwaungulu G.Black r.Ndhlovu E.Mwaiyeghele j.r.glynn D.K.Warndorff P.E.M.Fine 贺晓新 Karonga Prevention Study Chilumba Malawi Department of Infectious and Tropical Diseases London School of Hygiene and Tropical Medicine London UK MrC Laboratories Fajarao The Gambia Karonga Prevention Study Chilumba Malawi Department of Infectious and Tropical Diseases London-School of Hygieneand Tropical Medicine London UK MrC Laboratories Fajara The Gambia Department of Infectious and Tropical Diseases London School of Hygiene and Tropical Medicine London UK

地点:北马拉维Karonga地区。目的:比较在高HIV流行条件下两涂片法与三涂片法诊断肺结核的灵敏度和特异度。设计:共对1992例可疑肺结核病人进行了检查,这些病人都有在2-7天内进行的三涂片检查结果以及至少一份标本的培养检查结果。涂... 详细信息

地点:北马拉维Karonga地区。目的:比较在高HIV流行条件下两涂片法与三涂片法诊断肺结核的灵敏度和特异度。设计:共对1992例可疑肺结核病人进行了检查,这些病人都有在2-7天内进行的三涂片检查结果以及至少一份标本的培养检查结果。涂片先以金胺染色并在荧光显微镜下观察,阳性者再行萋尼氏染色并在光学显微镜下观察确诊。培养检查采用L(?)wenstein-jensen培养基接种法。标本的真阴性和真阳性根据培养检查结果而定。对两涂片法和三涂片法的诊断灵敏度、特异度以及阴性和阳性预测值进行了比较。结果:与培养结果相比,三涂片法的灵敏度、特异度以及阳性和阴性预测值分别是70％、98％、92％和92％。头两份标本的涂片检查可以给出相似的结果。在三涂片法发现的阳性病例中,两涂片法至少可以发现其中的97％。就具有HIV检查结果的病例而言,两涂片法诊断培阳病例的灵敏度与三涂片法相同。结论:在本研究条件下,应用荧光显微镜和光学显微镜,采用两涂片法替代三涂片法只略微降低了诊断灵敏度,但也稍微提高了诊断特异度;而且上述结果不受HIV感染状态的影响。考虑到误诊的高昂成本,提高诊断的特异度具有重要意义。在结核病控制实践中,由于采用两涂片法代替三涂片法可以节约大量时间。

关键词：结核病诊断痰涂片检查 HIV 非洲

Mathematical modelling of ball and plate system with experimental and correlation function-based model validation

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Control Theory and Technology 2024年第2期22卷 326-341页

作者： T.r.Dil Kumar S.j.Mija Department of Electrical Engineering National Institute of Technology CalicutKozhikode673601KeralaIndia

The ball and plate system is an inherently nonlinear under actuated benchmark system used for validating the performance of various control schemes. A mathematical model depicting the dynamics close to that of the system is very much required for such a test bed. In this correspondence, the complete nonlinear model, a simplified nonlinear model, and a linearized model of the ball and plate system are developed. The system comprises a ball and plate mechanism and a rotary servo unit. The ball and plate mechanism is modelled using the Euler–Lagrange method, whereas the rotary servo subsystem is modelled from the first principles. The nonlinear model of the combined system is developed by including the dynamics of the servo motor with gear and rolling resistance between the ball and the plate. The simplified nonlinear model of the system is obtained with suitable assumptions. The model is linearized around the operating point using the jacobian. The validity of the developed models is investigated through correlation function analysis. The open-loop response of the three models, viz., nonlinear, simplified nonlinear, and linearized models, is analyzed in the MATLAB/Simulink platform. Since the open-loop system is unstable, the experimental validation of the model is performed with a double-loop PSO (particle swarm optimization) PID control scheme.

关键词： Ball and plate system Correlation function Model validation Particle swarm optimization(PSO) PSO PID controller

On an isotropic porous solid cylinder:the analytical solution and sensitivity analysis of the pressure

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Applied Mathematics and Mechanics(English Edition) 2024年第9期45卷 1499-1522页

作者： H.ASGHArI L.MILLEr r.PENTA j.MErODIO Departamento de Matematica Aplicada a las TIC ETS de Ingenieria de Sistemas InformaticosUniversidad Politecnica de MadridMadrid 28031Spain School of Mathematics and Statistics University of GlasgowGlasgow G128QQU.K.

Within this work,we perform a sensitivity analysis to determine the influence of the material input parameters on the pressure in an isotropic porous solid *** provide a step-by-step guide to obtain the analytical solution for a porous isotropic elastic cylinder in terms of the pressure,stresses,and elastic *** obtain the solution by performing a Laplace transform on the governing equations,which are those of Biot's poroelasticity in cylindrical polar *** enforce radial boundary conditions and obtain the solution in the Laplace transformed domain before reverting back to the time *** sensitivity analysis is then carried out,considering only the derived pressure *** analysis finds that the time t,Biot's modulus M,and Poisson's ratio ν have the highest influence on the pressure whereas the initial value of pressure P_(0) plays a very little role.

关键词： sensitivity analysis Laplace transform cylindrical polar coordinate Biot's modulus cylinder

Stable diffusion gradients in microfluidic conduits bounded by fluid walls

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Microsystems & Nanoengineering 2024年第3期10卷 357-367页

作者： Federico Nebuloni Cyril Deroy Peter r.Cook Edmond j.Walsh Department of Engineering Science Osney Thermo-Fluids InstituteUniversity of OxfordOxford OX20ESUK Sir William Dunn School of Pathology University of OxfordOxford OX13REUK

Assays mimicking in vitro the concentration gradients triggering biological responses like those involved in fighting infections and blood clotting are essential for biomedical *** assays prove especially attractive as they allow precise control of gradient shape allied to a reduction in *** microfluidic devices are fabricated using solid plastics that prevent direct access to responding ***-walled microfluidics allows the manufacture of circuits on standard Petri dishes in seconds,coupled to simple operating methods;cell-culture medium sitting in a standard dish is confined to circuits by fluid walls made of an immiscible *** develop and experimentally validate an analytical model of diffusion between two or more aqueous streams flowing at different rates into a fluid-walled conduit with the cross-section of a circular *** solid walls,fluid walls morph during flows as pressures fall,with wall shape changing down the *** model is validated experimentally for Fourier numbersrescein diffusing between laminar *** enables a priori prediction of concentration gradients throughout a conduit,so allowing rapid circuit design as well as providing bioscientists with an accurate way of predicting local concentrations of bioactive molecules around responsive and nonresponsive cells.

关键词： walls diffusion attractive

Single-atom Pt on carbon nanotubes for selective electrocatalysis

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Carbon Energy 2024年第1期6卷 63-71页

作者： Samuel S.Hardisty Xiaoqian Lin Anthony r.j.Kucernak David Zitoun Department of Chemistry Bar Ilan Institute of Nanotechnology and Advanced Materials(BINA)Bar Ilan UniversityRamat GanIsrael Department of Chemistry Molecular Science Research HubImperial College LondonLondonUK

Utilizing supported single atoms as catalysts presents an opportunity to reduce the usage of critical raw materials such as platinum,which are essential for electrochemical reactions such as hydrogen oxidation reaction(HOr).Herein,we describe the synthesis of a Pt single electrocatalyst inside single-walled carbon nanotubes(SWCNTs)via a redox *** via electron microscopy,X-ray photoelectron microscopy,and X-ray absorption spectroscopy show the single-atom nature of the *** electrochemical behavior of the sample to hydrogen and oxygen was investigated using the advanced floating electrode technique,which minimizes mass transport limitations and gives a thorough insight into the activity of the *** single-atom samples showed higher HOr activity than state-of-the-art 30%Pt/C while almost no oxygen reduction reaction activity in the proton exchange membrane fuel cell operating *** selective activity toward HOr arose as the main fingerprint of the catalyst confinement in the SWCNTs.

关键词： confinement electrocatalysis hydrogen platinum single atom catalysts

Europium recovery process by means of polymeric nanoparticles functionalized with acrylic acid,curcumin and fumaramide

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journal of rare Earths 2024年第10期42卷 1950-1959页

作者： P.A.Martínez-Montoya j.M.del río A.de j.Morales-ramirez M.Corea Escuela Superior de Ingeniería Química e Industrias Extractivas ESIQIE-IPNDepartamento de Ingeniería Metalúrgica UPALM S/N Col.Lindavista Escuela Superior de Ingenieria Química e Industrias Extractivas ESIQIE-IPNLaboratorio de Investigación en Polímeros y NanomaterialesUPALM S/N Col.Lindavista Centra de Investigación e Innovación Tecnológica CIITEC-IPNCda.de CECATIs/n

Polymeric nanoparticles of poly(methyl methacrylate) were obtained by emulsion polymerization techniques in a proce ss of two *** particles were functionalized with acrylic acid,curcumin,and fumaramide and three series of polymeric particles were *** incorporation of functional groups was confirmed by Fourier transform-infrared spectrosocopy(FT-Ir) and ultraviolet-visible(UV-Vis) *** spherical morphology of particles with an average diameter of 100 nm was observed by scartning electron microscopy(SEM).The polymeric materials were used for recovery of [Eu]from synthetic *** nanoparticles show excellent chelation capacity to trap rare-earth ions,because they recover more than 85% of [Eu] at pH of *** images of SEM after extraction process show arrays between particles with larger average particle sizes to 1.5 *** addition,the particles have a good stripping capacity,exceeding 50% of it,maintaining their homogeneity in morphology and good stability in dispersion for the recovery and stripping processes.A pseudo-second model order is obtained for the extraction and stripping processes while the best results of stripping process are obtained at pH of6.

关键词： Chelating effect Emulsion polymerization Extraction process rare earths Stripping process [Eu]recovery

Associations of accelerometry-measured and self-reported physical activity and sedentary behavior with skeletal muscle energetics:The Study of Muscle,Mobility and Aging(SOMMA)

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journal of Sport and Health Science 2024年第5期13卷 621-630页

作者： Yujia(Susanna)Qiao Terri L.Blackwell Peggy M.Cawthon Paul M.Coen Steven r.Cummings Giovanna Distefano Samaneh Farsijani Daniel E.Forman Bret H.Goodpaster Stephen B.Kritchevsky Theresa Mau Frederico G.S.Toledo Anne B.Newman Nancy W.glynn Department of Epidemiology School of Public HealthUniversity of PittsburghPittsburghPA 15261USA San Francisco Coordinating Center California Pacific Medical Center Research InstituteSan FranciscoCA 94143USA Department of Epidemiology and Biostatistics University of CaliforniaSan FranciscoCA 94143USA Translational research Institute AdventHealthOrlandoFL 32804USA Department of Medicine(Geriatrics and Cardiology) University of Pittsburghand GeriatricsResearchEducationand Clinical Center(GRECC)VA Pittsburgh Healthcare SystemPittsburghPA 15261USA Department of Internal Medicine Section on Gerontology and Geriatric MedicineWake Forest School of MedicineWinston-SalemNC 27109USA Division of Endocrinology and Metabolism Department of MedicineUniversity of PittsburghPittsburghPA 15261USA

Background:Skeletal muscle energetics decline with age,and physical activity(PA)has been shown to offset these declines in older ***,many studies reporting these effects were based on self-reported PA or structured exercise ***,we examined the associations of accelerometry-measured and self-reported PA and sedentary behavior(SB)with skeletal muscle energetics and explored the extent to which PA and sedentary behavior would attenuate the associations of age with muscle ***:As part of the Study of Muscle,Mobility and Aging,enrolled older adults(n=879),810(age=76.4±5.0 years old,mean±SD;58%women)had maximal muscle oxidative capacity measured ex vivo via high-resolution re spirometry of permeabilized myofibers(maximal oxidative phosphorylation(maxOXPHOS))and in vivo by ^(31)phosphorus magnetic resonance spectroscopy(maximal adenosine triphosphate(ATP_(max))).Accelerometry-measured sedentary behavior,light activity,and moderate-to-vigorous PA(MVPA)were assessed using a wrist-worn ActiGraph GT9X over 7 ***-reported sedentary behavior,MVPA,and all PA were assessed with the Community Healthy Activities Model Program for Seniors(CHAMPS)*** regression models with progressive covariate adjustments evaluated the associations of sedentary behavior and PA with muscle energetics,as well as the attenuation of the age/muscle energetics association by MVP A and sedentary *** a sensitivity analysis,we also examined activPAL-measured daily step count and time spent in sedentary behavior and their associations with muscle ***:Every 30 min/day more of ActiGraph-measured MVPA was associated with 0.65 pmol/(s×mg)higher maxOXPHOS and 0.012 mM/s higher ATP_(max)after adjusting for age,site/technician,and sex(pr ATP_(max).Meanwhile,every 30 min/day spent in ActiGraph-measured sedentary behavior was associated with 0.39 pmol/s×mg lower maxOXPHOS and0.

关键词： Aging Exercise Mitochondria