简介：Thispaperpresentsamechanicalmodelofjumpingrobotbasedonthebiologicalmechanismanalysisoffrog.Bybiologicalobservationandkinematicanalysisthefrogjumpisdividedintotake-offphase,aerialphaseandlandingphase.Wefindthesimilartrajectoriesofhindlimbjointsduringjump,theimportanteffectoffootduringtake-offandtheroleofforelimbinsupportingthebody.Basedontheobservation,thefrogjumpissimplifiedandamechanicalmodelisputforward.Therobotlegisrepresentedbya4-barspring/linkagemechanismmodel,whichhasthreeDegreesofFreedom(DOF)athipjointandoneDOF(passive)attarsometatarsaljointonthefoot.TheshoulderandelbowjointseachhasoneDOFforthebalancingfunctionofarm.Thegroundreactionforceofthemodelisanalyzedandcomparedwiththatoffrogduringtake-off.Theresultsshowthatthemodelhasthesameadvantagesoflowlikelihoodofprematurelift-offandhighefficiencyasthefrog.Analysisresultsandthemodelcanbeemployedtodevelopandcontrolarobotcapableofmimickingthejumpingbehavioroffrog.

简介：Thetangentresistanceontheinterfaceofthesoil-moldboardisanimportantcomponentoftheresistancetomovingsoil.Wedevelopedsimplifiedmechanicalmodelstoanalyzethisresistance.Wefoundthatitiscomposedoftwocomponents,thefrictionalandadhesiveresistances.Thesetwocomponentsoriginatefromthesoilpore,whichinducedacapillarysuctioneffect,andthesoil-moldboardcontactareaproducedtangentadhesiveresistance.Thesetwocomponentsvarieddifferentlywithsoilmoisture.Thuswepredictedthatresistancereductionagainstsoilexertedonthenon-smoothbionicmoldboardismainlyduetotheeliminationofcapillarysuctionandthereductionofphysical-chemicaladsorptionofsoil.

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简介：Whendevelopingahumanoidmyo-controlhand,notonlythemechanicalstructureshouldbeconsideredtoaffordahighdexterity,butalsothemyoelectric(electromyography,EMG)controlcapabilityshouldbetakenintoaccounttofullyaccomplishtheactuationtasks.Thispaperpresentsanovelhumanoidroboticmyocontrolhand(ARhandⅢ)whichadoptedanunderac-tuatedmechanismandaforearmmyocontrolEMGmethod.TheARhandⅢhasfivefingersand15joints,andactuatedbythreeembeddedmotors.Underactuationcanbefoundwithineachfingerandbetweentherestthreefingers(themiddlefinger,theringfingerandthelittlefinger)whenthehandisgraspingobjects.FortheEMGcontrol,twospecificmethodsareproposed:thethree-fingeredhandgestureconfigurationoftheARhandⅢandapatternclassificationmethodofEMGsignalsbasedonastatisticallearningalgorithm-SupportVectorMachine(SVM).Eighteenactivehandgesturesofatesteearerecognizedef-fectively,whichcanbedirectlymappedintothemotionsofARhandⅢ.Anon-lineEMGcontrolschemeisestablishedbasedontwodifferentdecisionfunctions:oneisforthediscriminationbetweentheidleandactivemodes,theotherisfortherecog-nitionoftheactivemodes.Asaresult,theARhandⅢcanswiftlyfollowthegestureinstructionsofthetesteewithatimedelaylessthan100ms.

简介：新型的PHD22／2000Hpsi注射泵是一款在所有HarvardApparatus显微处理注射泵中具有最大容积输出的产品。该注射泵能够支持4个位于20～200ml体积的注射通道，或者多达10个位于100ml的注射通道。通过通道之间的结合使用，一个单位泵容积在第二次补液前能够维持1000ml体积的流体输出。对注射栓的压力输出能达到400磅。每单位体积具有±0．5％的精确性及0．1％的重复性。

简介：Anovelbionicswarmintelligencealgorithm,calledantcolonyalgorithmbasedonablackboardmechanism,isproposedtosolvetheautonomyanddynamicdeploymentofmobilessensornetworkseffectively.Ablackboardmechanismisintroducedintothesystemformakingpheromoneandcompletingthealgorithm.Everynode,whichcanbelookedasanant,makesoneinformationzoneinitsmemoryforcommunicatingwithothernodesandleavespheromone,whichiscreatedbyantitselfinnature.ThenantcolonytheoryisusedtofindtheoptimizationschemeforpathplanninganddeploymentofmobileWirelessSensorNetwork(WSN).Wetestthealgorithminadynamicandunconfigurableenvironment.Theresultsindicatethatthealgorithmcanreducethepowerconsumptionby13%averagely,enhancetheefficiencyofpathplanninganddeploymentofmobileWSNby15%averagely.

简介：Locomotionability,efficiencyandreliabilityarekeytargetsforagoodrobot.Thelinkagemechanismforrobotlocomotionisadiscontinuous-constraintmetamorphicmechanism.Herewesetupequationstopresentthediscontinuous-constraint,pointoutthatdrivingandcontrollingarethekeypointstoimprovetheperformanceandefficiencyofthelinkagemechanism.Inspiredbycontrollingstrategyofthemotornervoussysteminperipheralvertebraetothelocomotion,wedrawoffmotorcontrolanddrivestrategy.

简介：HLA-B27阳性患者人群中,内质网氨基肽酶1（ERAP1）基因多态性与强直性脊柱炎（AS）密切相关。内质网中,ERAP1可有效剪切抗原肽,使其成为适合HLA-Ⅰ类分子提呈的寡肽。ERAP1基因多态性决定N端抗原肽修剪功能的正常与否以及HLA-B27分子的稳定表达。细胞水平的研究表明,不同ERAP1等位基因组合对于抗原肽底物的修剪能力决定了B27分子能否在细胞表面稳定表达。但是,功能型与功能异常型ERAP1如何影响HLA-B27抗原肽加工、B27稳定表达,以及如何影响AS疾病进程和免疫病理学改变等均未得到阐明。

简介：Inanattempttorealizeaflappingwingmicro-airvehiclewithmorphingwings,wereportonimprovementstoourpreviousfoldableartificialhindwing.Multiplehinges,whichwereimplementedtomimicthebendingzoneofabeetlehindwing,weremadeofsmallcompositehingeplatesandtinyaluminumrivets.Thebuck-tailsofrivetswereflaredafterthehingeplateswereassembledwiththerivetssothatthefolding/unfoldingmotionscouldbecompletedinlesstime,andthestraightshapeoftheartificialhindwingcouldbemaintainedafterfabrication.Foldingandunfoldingactionsweretriggeredbyelectrically-activatedShapeMemoryAlloy(SMA)wires.Forwingfolding,theactuationcharacteristicsoftheSMAwireactuatorweremodifiedthroughheattreatment.Throughaseriesofflappingtests,weconfirmedthattheartificialwingsdidnotfoldbackandarbitrarilyfluctuateduringtheflappingmotion.

简介：Bionicnon-smoothsurfaces(BNSS)canreducedrag.Muchattentionhasbeenpaidtothemechanismofshearstressreductionbyriblets.Themechanismofpressureforcereductionbybionicnon-smoothsurfacesonbodiesofrevolutionhasnotbeenwellinvestigated.InthisworkCFDsimulationhasrevealedthemechanismofdragreductionbyBNSS,whichmayworkinthreeways.First,BNSSonbodiesofrevolutionmaylowerthesurfacevelocityofthemedium,whichpreventsthesuddenspeedupofaironthecrosssection.Sothebottompressureofthemodelwouldnotbedisturbedsharply,resultinginlessenergylossanddragreduction.Second,themagnitudeofvorticityinducedbythebionicmodelbecomessmallerbecause,duetothesculpturing,thegrowthoftinyairbubblesisavoided.Thusthelargemomentofinertiainducedbylargeairbubbleisreduced.Thereductionofthevorticitycouldreducethedissipationoftheeddy.Sothepressureforcecouldalsobereduced.Third,thethicknessofthemomentumlayeronthemodelbecomeslesswhich,accordingtotherelationshipbetweenthedragcoefficientandthemomentumthickness,reducesdrag.

简介：目的:结合临床分析肌酸激酶(CK)升高的原因,提高对CK的认识。方法:对我院生化检查CK升高患者结合临床资料进行分析。结果:感染、缺氧、低钾血症、心肌损伤、各种肌肉损伤、药物均能导致肌酸激酶升高。结论:临床医生在应用CK诊断疾病时,应结合临床症状及其他医技检查结果谨慎做出判断。

简介：Theobjectiveofthisstudyistoinvestigatethebiomechanicalfunctionsofthehumanankle-tootcomplexduringthestancephaseofwalking.Thethree-dimensional(3D)gaitmeasurementwasconductedbyusinga3Dinfraredmulti-camerasystemandaforceplatearraytorecordtheGroundReactionForces(GRF)andsegmentalmotionssimultaneously.Theankle-footcomplexwasmodelledasafour-segmentsystem,connectedbythreejoints:talocruraljoint,sub-talarjointandmetatarsophalangealjoint.Thesubject-specificjointorientationsandlocationsweredeterminedusingafunctionaljointmethodbasedontheparticleswarmoptimisationalgorithm.TheGRFmomentarmsandjointmomentsactingaroundthetalocruralandsub-talarjointswerecalculatedovertheentirestancephase.Theestimatedtalocruralandsub-talarjointlocationsshownoticeableobliquity.Thekinematicandkineticresultsstronglysuggestthatthehumanankle-footcomplexworksasamechanicalmechanismwithtwodifferentconfigurationsinstancephaseofwalking.TheseleadtoasignificantdecreaseintheGRFmomentarmstherebyincreasingtheeffectivemechanicaladvantagesoftheankleplantarflexormuscles.Thisreconfigurablemechanismenhancesmuscleeffectivenessduringlocomotionbymodulatingthegearratiooftheankleplantarflexormusclesinstance.Thisstudyalsorevealsmanyfactorsmaycontributetothelocomotorfunctionofthehumanankle-footcomplex,whichincludenotonlyitsre-configurablestructure,butalsoitsobliquelyarrangedjoints,thecharacteristicheel-to-toeCentreofPressure(COP)motionandalsothemediallyactingGRFpattern.Althoughthehumanankle-footstructureisimmenselycomplex,itseemsthatitsconfigurationandeachconstitutivecomponentarewelltunedtomaximiselocomotorefficiencyandalsotominimiseriskofinjury.Thisresultwouldadvanceourunderstandingofthelocomotorfunctionoftheankle-footcomplex,andalsotheintrinsicdesignoftheankle-footmusculoskeletalstructure.Moreover,this

简介：目的：构建带Myc标签的LC3B—PLA2基因的真核表达质粒，获得LC3B—PLA2融合蛋白，并应用LC3B—PLA2研究Atg4B对LC3B的切割作用。方法：以本实验室保存的乳腺文库为模板，PCR扩增获得LCgB序列，与PLA2G]O拼接后插入pCMV—Myc载体，用构建的重组质粒转染HEK293T细胞，Western印迹检测融合蛋白的表达，用LC3B—PLA2与Atg4B共转染的方法检测Atg4B对LC3B的切割作用。结果：菌液PCR、重组质粒双酶切及测序均表明重组质粒构建成功，Western印迹结果表明融合蛋白在HEK293T细胞中获得表达，LC3B—PLA2真核表达蛋白能够应用于Atg4B对LC3B切割作用的研究。结论：构建了pCMV—Myc—LC3B—PLA2真核表达质粒，LC3B—PLA2融合蛋白在Atg4B对LC3B切割作用的研究中至关重要，为进一步研究Atg4B在自噬过程中的作用奠定了基础。

简介：贝叶斯分类方法,是以概率假设为基础的.假设需要分类的数据遵循某种假设分别,通过这些概率分布以及对观察数据本身进行推理,得出最好的分类结果.本文重点介绍贝叶斯分类模型的相关理论基础以及常见的几种贝叶斯分类模型.

简介：利用基因工程表达的志贺毒素Ｂ亚基纯化产物研究志贺毒素的分子组装机理。首先对ＳｔｘＢ进行了分离纯化，并将蛋白质纯品溶解在磷酸缓冲液中。利用蛋白质交联的方法证实，在磷酸缓冲液体系中ＳｔｘＢ可以自发聚合为不同的分子结构形式（单体至五聚体），并可以与游离和细胞膜表面的受体结合，对志贺毒素全毒素的细胞毒性有竞争抑制作用。结果表明，在没有Ａ亚基存在的情况下，单独的ＳｔｘＢ也可以自发组装为多聚体，说明ＳｔｘＢ具有自身组装的能力。

简介：当前,一项称为“生命的条形码”计划正在欧美等国展开,其目的是实现对地球上现存的约1000万物种进行快速和准确的鉴定。DNA条形码是一种利用短的DNA序列对物种进行鉴定的技术。对DNA条形码的概念和原理进行了介绍,举例说明了其在物种分类、遗传多样性及物种鉴定研究中广泛的利用价值,阐述了当前该领域的研究现状,对未来的发展方向进行了展望。