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127 个结果
  • 简介:Thereisalargegapbetweenthenumberofmembraneprotein(MP)sequencesandthatoftheirdecoded3Dstructures,especiallyhigh-resolutionstructures,duetodifficultiesincrystalpreparationofMPs.However,detailedknowledgeofthe3DstructureisrequiredforthefundamentalunderstandingofthefunctionofanMPandtheinteractionsbetweentheproteinanditsinhibitorsoractivators.Inthispaper,somecomputationalapproachesthathavebeenusedtopredictMPstructuresarediscussedandcompared.

  • 标签: 膜蛋白 结构预测 晶体 活化剂 抑制因子
  • 简介:AIM:Toinvestigateandcomparethecytopathologicalandclinicaleffectsofamnioticmembranetransplantation(AMT)andoralmucosalmembranetransplantation(OMMT)insocketcontraction.METHODS:Twelvepatientswhocouldnotbefittedwithocularprosthesisduetosocketcontracturewereincludedinthisstudy.SevenpatientsunderwentAMTand5patientsunderwentOMMT.Thirteenpatientswhohadhealthysocketswereincludedascontrolgroup.Depthofinferiorfornix,degreeofinflammation,extentofthesocketcontractureandsocketvolumeweremeasuredinthepreoperativeperiodandatsixthandtwelfthweekspostoperatively.Impressioncytologyofconjunctivalfornicesandteartransforminggrowthfactorbeta-1(TGFβ1)levelsweredetermined.RESULTS:IntheAMTgroup,socketvolumeandlowerfornixdepthvaluesweresignificantlyhigher(P=0.030andP=0.004respectively)andinflammationlevelsandimpressioncytologystages(P=0.037andP=0.022respectively)weresignificantlylowerinpostoperativeperiodcomparedtopreoperativeperiod.IntheOMMTgroup,nostatisticaldifferenceswerefoundintermsofclinicalparameters,inflammationlevelsandimpressioncytologystagesofpreoperativeversuspostoperativevalues.PreoperativetearTGFβ1levelswerehigherinAMTandOMMTgroupscomparedtothecontrolgroup(25.5ng/mL,26.3ng/mLand21.7ng/mLrespectively).DecreasedtearTGFβ1levelswereobservedinboththeAMTandOMMTgroupspostoperatively(mediandecreasevalue=2.1ng/mLand2.7ng/mLrespectively).CONCLUSION:AMTisassociatedwithpostoperativeimprovementininferiorfornixdepth,socketvolume,inflammationandimpressioncytologylevelsandmaybeamoreproperalternativemethodthanOMMTinthemanagementofsocketcontracture.

  • 标签: socket reconstruction amniotic MEMBRANE ORAL MUCOSAL
  • 简介:题目:膜生物反应器处理港口含油废水的膜污染行为及群落结构演变研究目的:采用膜生物反应器处理港口含油废水。考察运行过程中膜污染行为特征,分析引起膜污染的关键影响因素,研究减弱膜污染的途径与方法;考察反应器内群落结构演变,分离鉴定优势菌种,揭示运行条件和进水水质等宏观环境与微生物微环境之间的对应关系。创新点:1.分析出膜表面累积的胞外蛋白是膜污染严重和过膜压力增大的关键诱因;2.基于YusufChisti和MurrayMooYoung提出的气提液体上升流速模型,结合胞外蛋白变化趋势,提出降低过膜压力上升速度和缓解膜污染进程的有效措施:3.针对处理港口含油废水的生物系统进行种群结构研究及优势菌属的分离与鉴定。方法:1.借助环境扫描电子显微镜(sEM)、能量色散x射线光谱仪(EDX)和傅里叶红外光谱仪(FTIR)等分析手段表征膜污染物的主要成分;2,基于YusufChisti和MurrayMooYoung提出的气提液体上升流速模型,提出缓解膜污染进程的措施,并验证所提措施的有效性(图3和9);3.通过巢式PCR-DGGE技术对处理港口含油废水的膜生物反应器不同运行阶段的微生物群落结构进行研究,并采用克隆技术对优势微生物进行菌种鉴定(图10和表3)。结论:1.采用一体化厌氧/好氧.膜生物反应器来处理港口含油废水的优点是对有机污染物和油类等污染物的去除效率高,但在其运行过程中膜污染严重。2.分析发现胞外聚合物是引起膜污染物的主要因素(图3-6);组分分析进一步表明膜表面累积的胞外蛋白是膜污染严重和过膜压力增大的关键诱因(图7~9)。3.通过增大反应器曝气量,调整反应器结构参数可有效降低过膜压力上升速度,缓解膜污染进程。4.反应器内细菌群落结构平稳。5.克隆测序结果表明:膜�

  • 标签: 膜污染 胞外聚合物 港口含油废水 群落结构
  • 简介:Thisreviewbeginswithabriefcommentaryonthediversityofplacentationmechanisms,andthengoesontoexaminetheextensivealterationswhichoccurintheplasmamembraneofuterineepithelialcellsduringearlypregnancyacrossspecies.Ultrastructural,biochemicalandmoregeneralmorphologicaldatarevealthatstrikinglycommonphenomenaoccurinthisplasmamembraneduringearlypregnancydespitethediversityofplacentaltypes-fromepitheliochorialtohemochorial,whichultimatelyformindifferentspecies.Toencapsulatetheconceptthatcommonmorphologicalandmolecularalterationsoccuracrossspecies,thattheyarefoundbasolaterallyaswellasapically,andthatmoreovertheyareanongoingprocessduringmuchofearlypregnancy,notjustaneventatthetimeattachment,braneduringearlypregnancyarekeytouterinereceptivity.

  • 标签: 原生质膜转换 妊娠 子宫 胎盘形成
  • 简介:Inthepresentstudythemembranefoulinginmicrofiltrationusedforcellharvestinginadeadendsystemhasbeeninvestigated.experimentalresultswereanalysedintermsofexitingmembranefiltrationmodelsandmembraneresistances.Thecakefiltrationmodel(CFM)andstandardblockingmodel(SBM)havebeenconsideredinthisstudy.Variousmembraneresistancesweredeterminedatdifferentprocessingtime,feedconcentrationandstirringspeed.Resistancestopermeationinthissystemincludefiltermedium,poreblocking,adsorption,cakelayerandconcentrationpolarization.

  • 标签: 微型过滤 薄膜堵塞 流动液体
  • 简介:Vibrationofacircularmembraneincontactwithafluidhasextensiveapplicationsinindustry.Thenaturalvibrationfrequenciesfortheasymmetricfreevibrationofacircularmembraneincontactwithaboundedincompressiblefluidarederivedinthispaper.Consideringsmalloscillationsinducedbythemembranevibrationinanincompressibleandinviscidfluid,thevelocitypotentialfunctionisusedtodescribethefluidfield.Twoapproachesareusedtoderivethefreevibrationfrequenciesofthesystem,whichincludeavariationalformulationandanapproximatesolutionemployingtheRayleighquotientmethod.Agoodcorrelationisfoundbetweenfreevibrationfrequenciesevaluatedbythesemethods.Finally,theeffectsofthefluiddepth,themassdensity,andtheradialtensiononthefreevibrationfrequenciesofthecoupledsystemareinvestigated.

  • 标签: 不可压缩流体 自由振动频率 振动膜 固有振动频率 速度势函数 粘性流体
  • 简介:Traumaticinjuriestothecentralnervoussystem(CNS),includingtraumaticbraininjury(TBI)andspinalcordinjury(SCI),ofteninvolveanimmediatemechanicaldamagetoplasmamembranethatsurroundsneuronalsomataandaxons.Thisinitialdisruptionofplasmamembranefollowinginjurieshasbeenconvincinglydemonstratedbyincreasedmembrane

  • 标签: 中枢神经系统 密封膜 外伤性 早期治疗 细胞膜通透性 脊髓损伤
  • 简介:Thecross-sectionandsurfacestructuresofwingmembranesfromthectenochasmatidpterosaurBeipiaopteruschenianuswereobservedthroughascanningelectronmicroscope(SEM).Theresultsshowthatthewingmembranecontainsahighdensityofbloodvessels,implyingstrongthermoregulatoryfunction,similartothatofabatwingmembrane.Thisisthefirstcomparisonofthemicrostructuresofpterosaurwingmembraneswiththoseofthemodernbat.Itisinferredthatabat-likephysiologyexists,atleastinrelativelysmallpterosaurssuggestingthatthesepterosaurswerewarm-blooded,activefliers.

  • 标签: 翼龙 显微结构 SEM 古动物
  • 简介:Thispapergivesallthetwo-dimensionalmembranemodelsobtainedfromformalasymptoticanalysisofthethree-dimensionalgeometricallyexactnonlinearmodelofathinelasticshellmadewithaSaintVenant-Kirchhoffmaterial.Therefore,theothermodelscanbequotedasflexuralnonlinearones.Theauthoralsogivestheformalequationssolvedbytheassociatedstresstensorandpointsoutthatonlyoneofthosemodelsleads,bylinearization,tothe“classical”linearlimitingmembranemodel,whosejuetificationhasalreadybeenestablishedbyaconvergencetheorem.

  • 标签: 非线性弹性壳体 渐近分析 收敛定理 利普希茨边界
  • 简介:对学习客观解剖并且cadaveric前臂的interosseous膜(马恩岛)的biomechanical特征。十radius-IOM-ulna结构从新鲜结冰死尸被收获测量马恩岛的腱的部分的长度,宽度和厚度的方法。然后,腱的部分与腱在测量以后属于的尺骨、光线的结束一起被孤立。半径的近似部分和尺骨的远侧的部分在牙齿的基础丙烯酸的树脂粉末被嵌入并且修理。嵌入的标本被MTS为全部张力的测试用10000N负担房间夹钳并且修理858测试机器。马恩岛以50mm/min的速度被拉长直到它被破裂。负担排水量曲线与一台计算机和最大的负担被描绘,僵硬同时被记录。结果前臂的马恩岛由三部分组成:中央腱的织物,膜的织物和背面的隶属于的倾斜的绳索。马恩岛在一个中立位置被拉长,并且在内转和旋后位置弯曲。当最大的负担的点到达了N到1021.50时,马恩岛的腱的部分在6个标本被撕碎吗?

  • 标签: 生物力学特性 解剖学 前臂 尸体 膜状 最大负荷
  • 简介:Membranealgorithms(MAs),whichinheritfromPsystems,constituteanewparallelanddistributeframeworkforapproximatecomputation.Inthepaper,amembranealgorithmisproposedwiththeimprovementthattheinvolvedparameterscanbeadaptivelychosen.Inthealgorithm,somemembranescanevolvedynamicallyduringthecomputingprocesstospecifythevaluesoftherequestedparameters.Thenewalgorithmistestedonawell-knowncombinatorialoptimizationproblem,thetravellingsalesmanproblem.Theempiricalevidencesuggeststhattheproposedapproachisefficientandreliablewhendealingwith11benchmarkinstances,particularlyobtainingthebestoftheknownsolutionsineightinstances.Comparedwiththegeneticalgorithm,simulatedannealingalgorithm,neuralnetworkandafine-tunednon-adaptivemembranealgorithm,ouralgorithmperformsbetterthanthem.Inpractice,todesigntheairlinenetworkthatminimizethetotalroutingcostontheCABdatawithtwenty-fiveUScities,wecanquicklyobtainhighqualitysolutionsusingouralgorithm.

  • 标签: 组合优化问题 遗传算法 自适应 求解 模拟退火算法
  • 简介:Rabbitlimbalcornealepithelialcells,cornealendothelialcellsandkeratocyteswereculturedonamnioticmembrane.Phasecontrastmicroscopeexaminationwasperformeddaily.Histologicalandscanelectronmicroscopicexaminationswerecarriedouttoobservethegrowth,arrangementandadhesionofcultivatedcells.Resultsshowedthatthreecornealcelltypesseededonamnioticmembranegrewwellandhadnormalcellmorphology.Culturedcellsattachedfirmlyonthesurfaceofamnioticmembrane.Cornealepithelialcellsshowedsingularlayerorstratification.Cellboundarieswereformedandtightlyopposed.Cornealendothelialcellsshowedcobblestoneorpolygonalmorphologiccharacteristicsthatappeareduniforminsize.Thecellulararrangementwascompact.Keratocyteselongatedandshowedtriangleordendriticmorphologywithmanyintercellularjointswhichcouldformnetworks.Inconclusion,amnioticmembranehasgoodscaffoldproperty,diffusioneffectandcompatibilitywithcornealcells.Thebasementmembranesideofamnioticmembranefacilitatedthegrowthofcornealepithelialcellsandendothelialcellsandcelljunctionsweretightlydeveloped.Thespongylayerofamnioticmembranefacilitatedthegrowthofkeratocytesandintercellularjointswererich.Amnioticmembraneisanidealbiomaterialforlayeringtissueengineeredcornea.

  • 标签: 角膜手术 羊隔膜 上皮生长细胞 生物材料
  • 简介:Aneigenvaluemethodconsideringthemembranevibrationofwrinklingout-of-planedeformationisintroduced,andthestressdistributingruleinmembranewrinkledareaisanalyzed.Adynamicanalyticalmodelofrectangularshearwrinkledmembraneanditsnumericalanalysisapproacharealsodeveloped.Resultsindicatethatthestressinwrinkledareaisnotuniform,i.e.itislargerinwrinklingwavepeaksalongwrinklesandtwoendsofwrinkleinverticaldirection.Vibrationmodesofwrinkledmembranearestronglycorrelatedwiththewrinklingconfigurations.Therigidityislargerduetotheheavierstressinthepartofwrinklingwavepeaks.Therefore,wavepeaksarealwayslocatedatthenodelinesofvibrationmode.Thevibrationfrequencyobviouslyincreaseswiththevibrationofwavepeaks.

  • 标签: 动态膜 起皱 力学性能 数值分析方法 振动模式 特征值方法
  • 简介:Compositediaphragminflation(CDI)experimentisausefulmethodologyforexploringthemechanicsrelationofcell-celljunctionswithinalivingepithelialsheet.Inthispaper,anewmethodologyofCDIexperimenthasbeenputforward.Thefinitedeformationofacircularpolydimezhylsiloxaneelastomericmembrane,whichisusedasthesubstrateforthecultureofepithelialcells,underhydrostaticpressureisexploredbythetheoryofnon-linearcontinuummechanics.Thesimplifiedgoverningequationswithminimumamountofdifferentialequationsandboundaryconditionsareobtainedandsolvedbymultipleshootingmethod.Theinfluencesonthemembranebyhydrostaticpressurehavebeendiscussed.

  • 标签: 通货膨胀率 弹性膜片 静水压力 圆形 上皮细胞 力学关系
  • 简介:RecentlytheCASQingdaoInstituteofBioenergyandProcessesincollaborationwiththeLeibnizUniversit?tHannover,ForschungszentrumJülichandBayerAGhasmadeattemptstocarryoutmethanearomatizationreactioninanoxygen-permeablemembranereactortoyield

  • 标签:
  • 简介:Althoughtheperformanceofmembranereactors(MR)ishighlyaffectedbytheratioofmembranearea-toreactionvolume,therearefewstudiesonthiseffectowingtothedifficultiesassociatedwithreactormanufacture.Inthisstudy,anMRwithhighA/Vratio,adiameterof35m,andaheightof0.8mmwasfabricated.SeparationperformanceofthisMRwasinvestigatedinann-butanol/watersystem.Esterificationofaceticacidandn-butanolwasusedasthemodelreactiontoinvestigatetheperformanceofcatalyticallyactivemembranereactors(CAMR)withdifferentA/Vratios.Thereactionconversionwas38.59%intheCAMRwiththehighA/Vratioof12,497/m,whichwasmuchhigherthanthatinotherCAMRs,forreactiontimeof60minandW/Vfratioof0.093g/mL.ExcellentcatalyticstabilityoftheCAMRwasconfirmedbyperforminglong-termstabilityexperiments.

  • 标签: Catalytically ACTIVE MEMBRANE REACTOR A/V ratios
  • 简介:在膜结构和他们的环境之间的相互作用能静态或动态。静态的相互作用与静态的空气指相互作用,当动态相互作用指风和它的效果时。他们能被抑制的二个参数,增加的团和放射/aerodynamic评估,它试验性地在这研究被调查。学习为动态相互作用为在相互作用参数和风方向和速度之间的静态的相互作用和关系在结构的动态特征,和在相互作用参数和膜结构的盖住的区域之间的关系上包括静态、动态的相互作用的效果。动态相互作用强烈与结构的模式被相关的试验性的数据表演,即,对称的模式的相互作用比反对称的模式大得多;并且动态相互作用的影响在导致风的反应分析是重要的并且不能被忽略。另外,结构的自然频率被这个相互作用显著地减少,这被结束,并且频率乐队显著地被拓宽。

  • 标签: 气相互作用 膜结构 风环境 实验 相互作用参数 结构动态特性