简介：ThispaperisfocusedonthemodelidentificationofaMicroAirVehicle(MAV)instraightsteadyflightcondition.Theidentificationisbasedoninput-outputdatacollectedfromflighttestsusingbothfrequencyandtimedomaintechniques.Thevehicleisanin-house40cmwingspanairplane.Becauseofthecomplexcoupled,multivariableandnonlineardynamicsoftheaircraft,linearSISOstructuresforboththelateralandlongitudinalmodelsaroundareferencestatewerederived.TheaimoftheidentificationistoprovidemodelsthatcanbeusedinfuturedevelopmentofcontroltechniquesfortheMAV.

简介：Fivekindsof45#steelsampleswithconcavefeaturesonthesurfaceweremanufacturedusingLaserTexturingTechnology(LTT).Optimumdesigntheorywasusedtodesigntheexperiment,andatwo-levelorthogonaltable-L16(215)designwasadopted.Micro-wearandmicro-frictionexperiencedbysampleswithconcavesurfacefeaturesandsampleswithsmoothsurfaceswerecomparedexperimentally.Thewearresistanceofsampleswithconcavesurfacefeatureswasincreasedmost,anddifferentsurfacemorphologieshaddifferenteffectsonfrictionandwearproperties.

简介：Naturalsurfaceswithsuperhydrophobicpropertiesoftenhavemicroorhierarchicalstructures.Inthispaper,thewettingbehavioursofasingledropletonbiomimeticmicrostructuredsurfaceswithdifferentroughnessparametersareinvestigated.Atheoreticalmodelisproposedtostudywettingtransitions.Theresultsoftheoreticalanalysisarecomparedwiththoseofexperimentindicatingthattheproposedmodelcaneffectivelypredictthewettingtransition.Furthermore,anumericalsimulationbasedonthemesoscaleLatticeBoltzmannMethod（LBM）isperformedtostudydynamiccontactangles,contactlines,andlocalvelocityfieldsforthecasethatadropletdisplaysonthemicrostructuredsurface.Asphericalwaterdropletwithrs=15μmfallsdowntoabiomimeticsquare-postpatternedsurfaceundertheforceofgravitywithaninitialvelocityof0.01m·s-1andaninitialverticaldistanceof20μmfromdropletcentretothetopofpots.Inspiteofahigherinitialvelocity,thedropletcanstillstayinaCassiestate;moreover,itreachesanequilibriumstateatt≈17.5ms,whencontactangleis153.16°whichisslightlylowerthanthepredictionofCassie-Baxter’sequationwhichgivesθCB=154.40°.

简介：Themolluskshellmobilizescalciumfromenvironmentforskeletalmineralization.Thisoccursthroughsynthesizingsolidsinsolutioninthepresenceoforganicmoleculesofspecificinteriorregionsoftheconchshell.TheultrastructureandmicrohardnessoftheHemifusustubaconchshelllivingintheHuang/Boseaareaareinvestigatedinthepaper.Itisshownthatthecompositionandmicrostructureofthemolluskshellvaryindifferentpositions.Theprodissoconchshellconsistsonlyofaragonitewiththecrossed-lamellarmicrostructure.WhilethespiralshellandthebodyshelloftheHemifusustubaconchshellarecomposedofonecalcitelayerandseveralaragonitelayers.Thecalcitelayerconsistsofcylindricalgrains,butthearagonitelayersarecrossed-lamellarultrastructureatthreesizescales.Theminimumstructuresize(thethird-orderlamella)isatabout20nm-80nm.Themarginofshellapertureisonlycomposedofcalcitewithcylindricalgrains.ThisnaturaloptimizationoftheshellmicrostructureisintimatelyduetothegrowthoftheOrganicmatrix.Atdifferentpositionsthemicrohardnessofmolluscshellisdifferentduetodifferentcrystalstructuresandcrystalarrangements.Thegrowthprocessofshellsallowsaconstantrenewalofthematerial,thusenablingtheirfunctionaladaptationtoexternalenvironments.

简介：Basedonphotogrammetrytechnology,anovellocalizationmethodofmicro-polishingrobot,whichisrestrictedwithincertainworkingspace,ispresentedinthispaper.Onthebasisofpinholecameramodel,anewmathematicalmodelofvisionlocalizationofautomatedpolishingrobotisestablished.Thevisionlocalizationisbasedonthedistance-constraintsoffeaturepoints.Themethodtosolvethemathematicalmodelisdiscussed.Accordingtothecharacteristicsofgrayimage,anadaptivemethodofautomaticthresholdselectionbasedonconnectedcomponentsispresented.Thecentercoordinateofthefeatureimagepointisresolvedbybilinearinterpolationgraysquareweightedalgorithm.Finally,themathematicalmodeloftestingsystemisverifiedbygloballocalizationtest.Theexperimentalresultsshowthatthevisionlocalizationsysteminworkingspacehashighprecision.

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简介：Micro-electrondiffraction(MicroED)isanemergingtechniquetousecryo-electronmicroscopetostudythecrystalstructuresofmacromoleculefromitsmicro-/nano-crystals,whicharenotsuitableforconventionalX-raycrystallography.However,thistechniquehasbeenpreventedforitswideapplicationbythelimitedavailabilityofproducinggoodmicro-/nano-crystalsandtheinappropriatetransferofcrystals.Here,wedevelopedacompleteworkflowtopreparesuitablecrystalsefficientlyforMicroEDexperiment.Thisworkflowincludesinsituon-gridcrystallization,single-sideblotting,cryo-focusionbeam(cryo-FIB)fabrication,andcryo-electrondiffractionofcrystalcryo-lamella.ThisworkflowenablesustoapplyMicroEDtostudymanysmallmacromolecularcrystalswiththesizeof2-10μm,whichistoolargeforMicroEDbutquitesmallforconventionalX-raycrystallography.Wehaveappliedthismethodtosolve2.5Acrystalstructureoflysozymefromitsmicro-crystalwithinthesizeof10×10×10μm^3.OurworkwillgreatlyexpandtheavailabilityspaceofcrystalssuitableforMicroEDandfillupthegapbetweenMicroEDandX-raycrystallography.

简介：TheproblemofflappingmotioncontrolofMicroAirVehicles(MAVs)withflappingwingswasstudiedinthispaper.Basedupontheknowledgeofskeletalandmuscularcomponentsofhummingbird,adynamicmodelforflappingwingwasdeveloped.AcontrolschemeinspiredbyhumanmemoryandlearningconceptwasconstructedforwingmotioncontrolofMAVs.Thesalientfeatureoftheproposedcontrolliesinitscapabilitiestoimprovethecontrolperformancebylearningfromexperienceandobservationonitscurrentandpastbehaviors,withouttheneedforsystemdynamicinformation.Furthermore,theoverallcontrolschemehasafairlysimplestructureanddemandslittleonlinecomputations,makingitattractiveforreal-timeimplementationonMAVs.Boththeoreticalanalysisandcomputersimulationconfirmsitseffectiveness.

简介：目的利用新型纳米颗粒造影剂结合Micro-CT成像技术,建立小鼠肝脏成像方法,并用于肝脏肿瘤的活体成像。方法6只6-8周龄雄性C57BL/6J小鼠随机分成A组和B组,分别尾静脉注射纳米颗粒造影剂ExiTronnano1200050μL和100μL;在注射前、注射后3min、24h、7d、14d、28d和56d对所有小鼠肝脏进行Micro-CT活体扫描;分别在小鼠肝左叶和肝右叶内选取感兴趣区（ROI）进行灰度值分析,比较不同时间点肝组织对比度的变化。确定合适的造影剂剂量,尾静脉注射至3只雄性16月龄HBV转基因肝癌模型小鼠（C组）,同上进行Micro-CT活体扫描,并于第56天全部安乐死后取肝脏观察病理学改变。结果A组和B组小鼠在注射不同浓度造影剂后,冠状位重建图像及肝脏感兴趣区的平均灰度值结果显示：肝脏实质造影后均比注射前明显增强,24h达到峰值,注射后56d内,小鼠肝脏感兴趣区的平均灰度值与注射前相比仍维持在较高的水平,B组显著高于A组（P〈0.01）,确定后续实验采用B组造影剂剂量（100μL）。C组注射100μL造影剂后,各时间点均能比较清楚地看到肝脏癌性结节存在,病理学观察发现肝脏出现非典型增生,肿瘤细胞核大,染色质加深和肝细胞坏死。结论利用纳米颗粒造影剂结合Micro-CT成像技术,成功建立了小鼠肝脏活体成像方法,并可应用于肝脏肿瘤的活体成像研究。

简介：Overthelastdecade,computationalmethodshavebeenintensivelyappliedtoavarietyofscientificresearchesandengi-neeringdesigns.Althoughthecomputationalfluiddynamics(CFD)methodhasplayedadominantroleinstudyingandsimu-latingtransportphenomenainvolvingfluidflowandheatandmasstransfers,inrecentyears,othernumericalmethodsforthesimulationsatmeso-andmicro-scaleshavealsobeenactivelyappliedtosolvethephysicsofcomplexflowandfluid-interfaceinteractions.Thispaperpresentsareviewofrecentadvancesinmulti-scalecomputationalsimulationofbiomimeticsrelatedfluidflowproblems.Thestate-of-the-artnumericaltechniques,suchaslatticeBoltzmannmethod(LBM),moleculardynamics(MD),andconventionalCFD,appliedtodifferentproblemssuchasfishflow,electro-osmosiseffectofearthwormmotion,andself-cleaninghydrophobicsurface,andthenumericalapproachesareintroduced.Thenewchallengingofmodellingbiomi-meticsproblemsindevelopingthephysicalconditionsofself-cleanhydrophobicsurfacesisdiscussed.

简介：Chip-basedflow-throughPCRimplementsthePCRasacontinuousprocessfornucleicacidanalytics.Thesampleistransportedinawindingchannelthroughtemperaturezonesrequiredfordenaturation,annealingandextension.Mainfieldsofapplicationarethemonitoringofcontinuousprocessesforrapididentificationofcontaminantsandqualitycontrolaswellashighthroughputscreeningofcellsormicroorganisms.Amodulararrangementwithfiveheatingzonesforflow-throughPCRisdiscussedandevaluated.Thespecialheaterarrangementallowstheimplementationofupto40cyclesonthefootprintofamicroscopeslide,whichisplacedontopofa5zonesheatingplate.Liquid/liquidtwophaseflowofPCRreactionmixtureandmineraloilhavebeenappliedtocreateasegmentedflowprocessscheme.Inthatway,thedevelopedsystemmayprovideflow-throughPCRasaunitoperationforthedropletbasedmicrofluidicsplatform.ThesingleuseofdisposabledevicesiscommonlypreferredduetothesensitivityofthePCRprocesstocontaminations.All-glassmicrofluidicchipsanddisposablechipdevices,madefrompolycarbonateasareplicationwithidenticallygeometry,havebeenfabricatedandtested.Forthefirsttime,microchannelgeometrieswithnearlycircularprofiledevelopedbyall-glasstechnologyhavebeentransferredtomassfabricationbyinjectioncompressionmolding.Bothdeviceshavebeensuccessfullyappliedforthedetectionofthetumorsuppressorgenep53.Althoughproductyieldandselectivityoftheamplificationprocessdonotdependonthechipmaterial,awelldefined,reliablesegmentedflowregimecouldonlyberealizedintheall-glasschip.

简介：由endoparasitic黄蜂Pteromaluspuparum的寄生状态(Hymenoptera：Pteromalidae)由使用仅仅它的联系毒液，能压制Pierisrapae的immunal回答(鳞翅目：Pieridae)。直到现在，然而，机制的当前的知识被限制了。到寄生状态的主人血球的反应用光和传播电子显微镜学(TEM)的联合被调查。五种血球类型，prohemocytes(PR)，granulocytes(GR)，plasmatocytes(请)，oenocytoids(OE)和coagulocytes(公司)，从unparasitized被观察并且描绘并且寄生于Pierisrapae蛹。轻显微镜学显示出那GR并且请周围成为了更多并且在寄生状态以后反常地传播了，而血球的另外的类型的形状仍然保持未受影响。另外，当OE变得更小时，PR并且请的尺寸变得更大。PR的比例显著地在寄生状态和的以后增加了请在43.9%减少了，但是没有GR和OE的重要增加。TEM证明除了公司的血球的所有类型在寄生状态以后被损坏到各种各样的度，特别导致电子不透明的细胞质和原子核，不平的endoplasmic蜂窝胃的更少房间细胞器，线粒体和泡。我们的结果由P显示那个寄生状态。puparum影响微分血球计数和主人血球的结构，特别地为GR并且请，它可以是压制主人的parasitoid的主要原因细胞的有免疫力的回答。