简介:Thepurposeofthispaperistostudycompletespace-likesubmanifoldswithparallelmeancurvaturevectorandflatnormalbundleinalocallysymmetricsemi-defnitespacesatisfyingsomecurvatureconditions.WefirstgiveanoptimalestimateoftheLaplacianofthesquarednormofthesecondfundamentalformforsuchsubmanifold.Furthermore,thetotallyumbilicalsubmanifoldsarecharacterized.
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简介:Parthenogeneticembryonicstemcellshavepluripotentdifferentiationpotentials,akintofertilizedembryo-derivedembryonicstemcells.Theaimofthisstudywastocomparetheneuronaldifferentiationpotentialofparthenogeneticandfertilizedembryo-derivedembryonicstemcells.Beforedifferentiation,karyotypeanalysiswasperformed,withnormalkaryotypesdetectedinbothparthenogeneticandfertilizedembryo-derivedembryonicstemcells.SexchromosomeswereidentifiedasXX.Immunocytochemistryandquantitativereal-timePCRdetectedhighexpressionofthepluripotentgene,Oct4,atboththemRNAandproteinlevels,indicatingpluripotentdifferentiationpotentialofthetwoembryonicstemcellsubtypes.Embryonicstemcellswereinducedwithretinoicacidtoformembryoidbodies,andthendispersedintosinglecells.SinglecellsweredifferentiatedinN2differentiationmediumfor9days.Immunocytochemistryshowedparthenogeneticandfertilizedembryo-derivedembryonicstemcellsbothexpresstheneuronalcellmarkersnestin,βIII-tubulinandmyelinbasicprotein.Quantitativereal-timePCRfoundexpressionofneurogenesisrelatedgenes(Sox-1,Nestin,GABA,Pax6,Zic5andPitx1)inbothtypesofembryonicstemcells,andOct4expressionwassignificantlydecreased.NestinandPax6expressioninparthenogeneticembryonicstemcellswassignificantlyhigherthanthatinfertilizedembryo-derivedembryonicstemcells.Thus,ourexperimentalfindingsindicatethatparthenogeneticembryonicstemcellshavestrongerneuronaldifferentiationpotentialthanfertilizedembryo-derivedembryonicstemcells.
简介:Oneofmanyinterestingresearchactivitiesinbiofluidmechanicsisdedicatedtoinvestigationsoflocomotioninwater.Someofpropulsionmechanismsobservedintheunderwaterworldareusedinthedevelopmentprocessofunderwaterauto-nomicvehicles(AUV).Inordertocharacteriseseveralsolutionsaccordingtotheirmanoeuvrability,influenceonthesur-roundingfluidandenergeticefficiency,adetailedanalysisoffin-likemovementisindispensable.Inthecurrentpaperananalysisofundulatory,oscillatoryandcombinedfin-likemovementsbymeansofnumericalsimulationiscarriedout.TheconservationequationofmassandtheconservationequationofmomentumaresolvedwiththeFiniteVolumeMethod(FVM)byuseofthesoftwareCFX-10.0.Theundulatoryandoscillatoryfinmovementsaremodelledwithanequationthatisimplementedwithinanadditionalsubroutineandjoinedwiththemainsolver.Numericalsimulationsarecarriedoutinthecomputationaldomain,inwhichonefinisfixedinaflow-throughwaterduct.SimulationsarecarriedoutintherangeoftheRenumberupto105.Theresultsshowsignificantinfluenceofappliedfinmotiononthevelocitydistributioninthesurroundingfluid.
简介:Thepurposeofthispaperistoinvestigatetheiterativealgorithmforfindingapproximatesolutionsofaclassofmixedvariational-likeinequalitiesinarealHilbertspace,wheretheiterativealgorithmispresentedbyvirtueoftheauxiliaryprincipletechnique.Ononehand,theexistenceofapproximatesolutionsofthisclassofmixedvariational-likeinequalitiesisproven.Ontheotherhand,itisshownthattheapproximatesolutionsconvergestronglytotheexactsolutionofthisclassofmixedvariational-likeinequalities.
简介:Invitrocellloadingexperimentsareusedtoinvestigatestimulationofstraintocellularproliferation.Astheflowingconditionsofculturefluidinloadingsystemshasbeenlittleknown,strictlypeoplecannotdetecttheinfluenceofstraintocellularproliferationexactlybecauseshearflowcanenhancecellproliferationeither.Basedontheworkingprincipleandcyclicloadingparameters,wesimplifyNavier-Stokesequationtodescribetheflowofculturefluidonsubstratesofuniaxialandequi-biaxialfiattensileloadingsystemsandfourpointbendingsystem.Withapproximatesolutions,thedistributionsofvelocityfieldandwallshearflowtocellsaregained.Resultsshow:shearflowsarezerointhemiddle(orfixedpointorline)ofsubstrateforallsystems,andtheygetlargerproportionallytodistancefrommiddleandsubstrateelongate;theshearflowonthesubstrateoffourpointbendingsystemismuchgreaterthanthoseofothers.Thisshearflowinfourpointbendingsystem,confirmedbyOwan,I.,etalwithOPNmRNAincreaseintheirexperiment,couldcausemoreinfluencetoosteoblast-likecellsthanthatcausedbystrain.WeestimatetheaveragemagnitudeofshearstressinOwan'sdevice,theresultsareconsistentwithotherexperimentaldataaboutshearflow.Inconclusionourstudymakesitpossibletodifferentiatetheinfluenceofstrainoncellularproliferationtothatofshearflowinloadingexperimentswiththedevicesmentionedabovequantitatively.
简介:Locomotionability,efficiencyandreliabilityarekeytargetsforagoodrobot.Thelinkagemechanismforrobotlocomotionisadiscontinuous-constraintmetamorphicmechanism.Herewesetupequationstopresentthediscontinuous-constraint,pointoutthatdrivingandcontrollingarethekeypointstoimprovetheperformanceandefficiencyofthelinkagemechanism.Inspiredbycontrollingstrategyofthemotornervoussysteminperipheralvertebraetothelocomotion,wedrawoffmotorcontrolanddrivestrategy.
简介:记Lq为两个变量的量子环面上的斜导子李代数,当0≠q∈C为非单位时,Lq就是q-类似Virasoro-like代数.本文给出了文中构造的Lq的模上的导子及一上同调群H^1(Lq,M).
简介:<正>教学目标:1.听懂,会读,会说puppetpuzzlelove.2.能听懂,会读,会说,会写kitelike.3.能听懂,会读,会说,会写Ilike/love….Metoo.4.能听懂,会读,会说,会写What’sthis/thatinEnglish?It’sa/an…Doyoulike…?Yes,Ido.No,Idon’t.教具准备:1.教师:纸盒,木偶,拼图各一个,糖果,巧克力各一些。制作的多媒体课件。2学生:自带一些实物用于课堂操练。教学重难点:What’sthis/thatinEnglish?It’sa/an…Doyoulike…?教学过程:一、游戏激趣,愉快导入1.T:Classbegins.Goodmorning,boysandgirls.Howareyou?What’sinyourpencilcase?S:…(师生之间的freetalk,复习巩固前三单元的知识。)2.T:What’sthis?S:It’sapencilcase.