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500 个结果
  • 简介:Anewapparatuswasdesignedtomeasuretheelectromagneticforceandacomputationalstudyofthetravelingmagneticfield(TMF)anditsapplicationtotheGa-In-Snmelt(withlowmeltingpoint),thentheforcesonAl,Mg,andLimelt,weresimulated.TheresultshowthattheelectromagneticforceonthemeltincreaseslinearlywiththeincreasinglengthofthemeltintheTMF.TheTMF-inducedLorentzforceincreaseswithincreasingfrequency,andthendecreases.Themaximumvalueisobtainedwhenthecurrentfrequencyis160Hz,overthatfrequencytheforcedecreasesrapidly.Whentheiron-coreisactivated,theforceincreaseswhenthemeltclosestotheiron-core.TheLorentzforceshaveinversely-proportionalrelationshipswiththeelectricalresistivity,thedfx/dρdecreasesandthedfy/dρincreaseswiththeincreasingelectricalresistivity(df/dρistheslopeoftheLorentzforceprofile).

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  • 简介:OurexperimentsshowthatexternalfocusingandinitiallaserenergystronglyinfluencesfilamentgeneratedbythefemtosecondTi–sapphirelaserinair.Theexperimentalmeasurementsshowthefilamentlengthcanbeextendedbothbyincreasingthelaserenergyandfocallengthoffocusinglens.Ontheotherhand,theplasmafluorescenceemissioncanbeenhancedbyincreasingthelaserenergywithfixedfocallengthordecreasingthefocallength.Inaddition,thecollapsedistancemeasuredexperimentallyarelargerthanthecalculatedonesowingtothegroup-velocity-dispersioneffect.Inaddition,wefindthatthelinewidthsofthespectrallinesfromN2isindependentoffilamentpositions,laserenergiesandexternalfocusing.

  • 标签: FEMTOSECOND LASER FILAMENT FLUORESCENCE
  • 简介:QBO-likeOscillationsInducedbyLocalThermalForcingZhangDaizhou;(张代洲),andQinin(秦瑜)(DepartmentofGeophysics,PekingUniversity,Beiji...

  • 标签: Quasi-biennial oscillation(QBO) LOCAL thermal FORCING FORCED
  • 简介:WiththerapiddevelopmentofforeigntradeinChina,industrialimportandexporthasbeenanabsolutesubjectinrecentyears.Thehugetradesurplusofimportandexporttradeofindustrialproductsbringsnotonlyhighprofits,butalsopollutioncostsaswell.Basedontheconceptofwaterpollutionfootprints(WPFs),thisstudyappliestheinput-outputmethodandcalculatespollutant-producingcoefficientsof20majorindustrialsectorsinChinaandinvestigatestheWPFscausedbytheimportandexporttradesoftheseindustrialsectors.TheresearchresultsshowthatWPFresultingfromexportsexceedsthatofimportsfrom2011to2015inChina.Thenetinflowofpollutionfootprintismainlyfrompapermills,printingandstationerymanufacturing,andtextileindustry;whereasagreatnumberofWPFsaretransferredtoothercountriesbythesesectors,suchasmetalmininganddressingindustryandoilandnaturalgasexploitationindustry.

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  • 简介:在这篇论文,稳定性;有时间延期的小世界的网络的Hopf分叉被学习。由分析延期的变化,我们在马厩上获得几个足够的条件;不稳定的性质。当延期传递批评价值时,Hopf分叉可以出现。而且,方向;区分周期的答案的稳定性被正常形式理论调查;中心歧管减小。由数字模拟,最后,我们进一步在这篇论文说明定理的有效性。

  • 标签: HOPF分歧 时滞 小世界网络 网络理论
  • 简介:与他们在文化经历无限的自强并且在身体区分进所有房间类型的能力,人的胚胎的干细胞(hESCs)为治疗保持大潜力当前不治之症。为针的绳索损害和有斑点的退化的二基于hESC的房间治疗被推进了进人的临床的试用。尽管有这快速的进步,基于hESC的房间治疗的一关键挑战是由接受者的导出hESC的房间的allogeneic免疫者拒绝。这个问题能被病人特定的体的房间的原子reprogramming被最近的突破与定义因素在导致的pluripotent干细胞(iPSCs)的技术减轻它能为房间治疗成为自体同源的房间的可更新的来源。然而,揭示反常epigenetics,genomic稳定性和iPSCs的immunogenicity的最近的研究在基于iPSC的治疗上提起了安全担心。与iPSC衍生物的immunogenicity有关的最近的调查结果将在这评论被总结。

  • 标签: 多能干细胞 免疫原性 衍生 诱导 胚胎干细胞系 人类胚胎
  • 简介:在vivo,研究证明那个树枝状的房间(DC)机能障碍发生在肿瘤微型环境。当肿瘤由许多种房间组成,不成熟的DC(imDCs)上的肿瘤房间的直接效果在vitro为进一步的研究被需要。在现在的学习,骨头导出髓的imDCs在vitro与淋巴瘤,hepatoma和menaloma房间被孵化,在imDCs的表面分子被流动cytometry决定。然后,imDCs与肿瘤孵化了房间或控制imDCs进一步与肿瘤lysates被搏动然后与splenocytes孵化了执行混合淋巴细胞反应。DC依赖的肿瘤抗原特定的T房间增长,和IL-12分泌物被流动cytometry,和连接酶的immunosorbent试金分别地决定。最后,DC依赖的联系肿瘤的抗原特定的CTL被连接酶的immunospot试金决定。结果显示出那肿瘤cell-DC孵化下面调整在imDCs的表面分子例如CD80,CD54,CD11b,CD11a和MHC班II分子。DC依赖的抗原特定的T房间增长和IL-12分泌物的能力被肿瘤房间孵化也在vitro减少。最重要地,为DC的antigenic特定的CTLpriming的能力被孵化也与肿瘤房间减少。在礼品,在vitro,学习证明肿瘤房间合作孵化和合作孵化系统导致的DC的有缺点的能力可能直接为肿瘤免疫者房间的未来学习是有用的相互作用并且为药屏幕有免疫力调整。

  • 标签: 树状细胞 免疫学 功能障碍 肿瘤
  • 简介:AIM:Toestimatethepotentialsystemiceventsduringandafterretinopathyofprematurity(ROP)screening.METHODS:Aprospectiveanddescriptivedesignedstudywasconductedtodetectthephysiologicandpathologicalchanges24hbefore,during,and72hafterROPscreening.Controlbloodpressure(BP),saturation,pulserate,andbodytemperaturewereroutinelytakenatvarioustimeinternalsbeforeandafterscreening.Adverseeffectspertaintocardiovascularsystem,respiratorysystem,gastricsystem,urinarysystemandnervoussystemwereretrospect0-72hafterROPscreeningata24-hourinterval.RESULTS:Totally1254prematuritybabiesreceivingROPscreeningduringJan.1st2013toDec.31th2013wereenrolledinoursurvey.Comparedtocontrolvitalsigndatatakenbeforetheexamination,therewasafluctuationinthediastolicBPwiththeincreased3.03mmHg(P=0.04)after3dosesofmydriaticdrops.Immediatelyaftertheexamination,therewasafurther12.64mmHg(P<0.01)increaseinsystolicBPanda7.24mmHg(P<0.01)indiastolicBP.Themeanpulserateduringexaminationwas22.4bpm(P<0.01)higherthanthe133.3±9.0bpmcontrollevel.Theoxygensaturationsharedanaveragedropof5%(P<0.01)duringscreening.Inprematuritywithpostconceptionalagelessthan31wk,theincidenceofapnea(23.5%),necrotizingenterocolitis(NEC)(8.7%),gastricresidual(25.4%)andupperdigestivetracthemorrhage(6.4%)alsodemonstratedasignificantrise(P<0.01).CONCLUSION:Inourstudysample,ROPscreeningwasassociatedwithNEC,gastricresidualandupperdigestivetracthemorrhage.Thesegastrointestinalsideeffects,alongwithbreathactivitypatternchangeandvitalsignsindicatorsfluctuation,mayberesultsofadditionalstressresponses.

  • 标签: retinopathy of PREMATURITY PREMATURITY SCREENING APNEA
  • 简介:Ithasbeenknownforsometimethatstraininjuriesoccurthroughtheexcessivelengtheningofamuscle.~(1–3)However,theprecisemechanismforstraininjuryremainselusiveandhasbeenthesubjectofrecentdebateintheJournalofSportandHealthScience,~(4–9)butitseemssensibletoconsidermechanismsatthelevelofthemusclefiber.Itwaspreviouslybelievedthatdamagewastheresultofnon-uniformstretchingofsarcomeres

  • 标签: 肌联蛋白 损伤机制 应变诱导 肌肉纤维 最佳长度 肌原纤维
  • 简介:ThePMD-inducedpulsebroadeningmaycausethedegradationofreceiversensitivityandhasnegativeeffectsonthepowerspectrumofreceivedsignals.TheexpressionsofPMD-inducedpulsebroadeningeffectsonreceiversensitivityarederivedbasedontheconceptofmeansquarepulsewidth.TheeffectsofPMDonthespectrumofreceivedpowerareanalyzedindetail.Finally,theschemeisdiscussedwithwhichthepowerofacertainfrequencycomponentisextractedasafeedbackcontrolsignalinaPMDcompensationsystem.

  • 标签: 光纤通信 偏振分散 接收机 灵敏度 电源频率光谱
  • 简介:ObjectiveTodetectearlysignsofnoise-inducedhearingloss(NIHL)inmilitarypilotswithouthearingcomplaints.MethodsPuretoneaudiometryandacousticreflexthresholdsweretestedin36militarypilots(72ears)withnoiseexposurehistorybutnocomplaintsofhearingloss.Conventionaltestfrequencies(0.25-8kHz)andextendedhighfrequencies(EHF,10and12.5kHz)wereincludedinaudiometry.Whitenoiseandpuretonesat0.5,1,2,and4kHzwereusedforacousticreflextests.Twentynormalhearingsubjects(40ears)withnoexposuretooccupationalnoisewereusedascontrols.ResultsPuretonethresholdsatallconventionalfrequenciesandatEHFswereelevatedinthepilots,withthemaximumshiftat4kHz,comparedwithcontrols(p<0.01).ThepilotsalsoshowedelevatedARTtowhitenoiseanddecreaseddifferentialsbetweenwhitenoiseandpuretoneARTs(p<0.01).ConclusionEarlysignsofNIHLarepresentinsomesymptom-freemilitarypilots.Highfrequencyhearingthresholdshift,elevatedwhitenoiseARTanddecreaseddifferentialbetweenwhitenoiseandpuretoneARTsmaybeobjectiveindicatorsofearlyNIHL.

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  • 简介:Inthispaper,opticalcross-connection(OXC)inducedcrosstalkhasbeencarefullyanalyzedformultiwavelengthall-opticalnetworks.Formulaearederivedforcalculatingthecrosstalkpowerofhomowavelengthcrosstalkandthetotalcrosstalkatthereceiverend.TheresultsshowthattheopticalswitchesinducedcrosstalkdominatesoverothercrosstalkcomponentsofOXC,andtheaccumulatedhomowavelengthcrosstalkincreasesalmostlinearlywiththeincreasingoftheOXCnumber.Atthereceiverend,theheterowavelengthcrosstalkinducedbythereceiveropticalfilterhasthesameorderasthatofhomowavelengthcrosstalkofOXC.Theresultsofdifferentopticalcomponentsmodelarealsodiscussed.

  • 标签: 光交叉连接器 光网络 光交换 通信网
  • 简介:Ahybridcontrolplatformisinvestigatedinthispapertomitigatemicrovibrationstoagroupofvibrationsensitiveequipmentinstalledinamicroelectronicsfacilitysubjecttonearbyroadvehicle-inducedhorizontalandverticalgroundmotions.Thehybridcontrolplatform,onwhichmicroelectronicsequipmentisinstalled,ismountedonabuildingfloorthroughaseriesofpassivemountsandcontrolledbyhydraulicactuatorsinbothhorizontalandverticaldirections.Thecontrolplatformisanelasticbodywithsignificantbendingmodesofvibration,andasub-optimalcontrolalgorithmisusedtomanipulatethehydraulicactuatorswithactuatordynamicsincluded.Thefiniteelementmodelandtheequationsofmotionofthecoupledplatform-buildingsystemarethenestablishedintheabsolutecoordinatetofacilitatethefeedbackcontrolandperformanceevaluationoftheplatform.Thehorizontalandverticalgroundvibrationsatthebaseofthebuildinginducedbynearbymovingroadvehiclesareassumedtobestationaryrandomprocesses.Atypicalthree-storymicroelectronicsbuildingisselectedasacasestudy.Thecasestudyshowsthattheverticalvibrationofthemicroelectronicsbuildingishigherthanthehorizontal.TheuseofahybridcontrolplatformcaneffectivelyreducebothhorizontalandverticalmicrovibrationsofthemicroelectronicsequipmenttothelevelwhichsatisfiesthestringentmicroscalevelocityrequirementspecifiedintheBoltBeranek&Newman(BBN)criteria.

  • 标签: 微小振动 道路交通 微电子工程 有限元分析
  • 简介:AbstractNeurosurgical procedures cause inevitable brain damage from the multitude of surgical manipulations utilized. Incisions, retraction, thermal damage from electrocautery, and intraoperative hemorrhage cause immediate and long-term brain injuries that are directly linked to neurosurgical operations, and these types of injuries, collectively, have been termed surgical brain injury (SBI). For the past decade, a model developed to study the underlying brain pathologies resulting from SBI has provided insight on cellular mechanisms and potential therapeutic targets. This model, as seen in a rat, mouse, and rabbit, mimics a neurosurgical operation and causes commonly encountered post-operative complications such as brain edema, neuroinflammation, and hemorrhage. In this review, we elaborate on SBI and its clinical impact, the SBI animal models and their clinical relevance, the importance of applying therapeutics before neurosurgical procedures (i.e., preconditioning), and the new direction of applying venom-derived proteins to attenuate SBI.

  • 标签: Brain injury Cerebral edema Preconditioning Neurotherapeutics Venom therapies
  • 简介:Thisletterpresentsanewanalyticalapproximationforwave(current)-induceddynamicsoilresponseinmarinesediments.Inthemodel,thethird-orderapproximationforwave-currentinteractionsisemployedfortheflowmodel,whileBiot’sdynamicporo-elasticmodelisusedtosimulatetheporousflowinaseabed.Thenewlyanalyticalsolutionisvalidatedwiththefieldobservations.Basedonthesolution,effectsofcurrentsandwave-nonlinearityonsoilresponseareexaminedandaparametricstudywillbecarriedouttoexaminetheinfluenceofcurrentsontheliquefactionpotential.

  • 标签: 海洋沉积物 电流 土壤 反应 流量模型 动态变化
  • 简介:Stochasticresonance(SR)phenomenonofthesystemthatissubjecttotheasymmetrictwo-statenoiseisinvestigatedfromthebroadsense.Itisshownthattheamplitudesoftheoutputsignalexhibitthenon-monotonicdependenceontheinputsignalfrequencyω,andtheparametersdescribingtheasymmetrictwo-statenoise,suchasthetransitionrateλ,theorderparameterkdescribingtheasymmetricdegreeofthetwo-statenoise,andthenoisestrengthD.

  • 标签: 分叉噪音 随机响应 不对称性 信号频率 参数
  • 简介:Near-fleldcoupledplasmonicsystemsgenerallyachieveplasmonicallyinducedtransparency(PIT)usingonlyone-waybright-darkmodecoupling.However,itischallengingtorealizesuchwell-designeddevices,mainlybecausetheydependsignificantlyonthepolarizationdirection.Weexploitsurfaceplasmonssup-portedbytwocrossedlayersofgraphenenanoribbons(GNRs)toachievedynamicallytunablePIT,whereeachGNRoperatesasboththebrightanddarkmodessimultaneously.TheproposedPITcanresultfromeitherone-waybright-darkmodeinteractionsorbidirectionalbright-brightandbright-darkmodehybrid-izedcouplingwhenthepolarizationisperpendicular/paralleloratanangletotheGNRs,respectively.Additionally,identicalribbonwidthsyieldpolarization-insensitivesingle-windowPIT,whereasdifferentribbonwidthsproducepolarization-dependentdouble-windowPIT.Weexaminetheproposedtechniqueusingplasmonwavefunctionsandthetransfermatrixmethod;analyticalandnumericalresultsshowex-cellentagreement.ThisstudycanprovidephysicalinsightintothePITcouplingmechanismsandadvancetheanulicabilitvandversatilityofPIT-basedsensingplatformsandotheractivedevices.

  • 标签: 近场耦合 等离子体系统 通讯技术 发展现状
  • 简介:Wereportsingle-shotdamagethresholdasafunctionofpulseduration(50-900fs)forMgF2/ZnS800-nmomnidirectional-reflectionfilm,interferencefilter,andgoldfilm.Theresultsindicatethatthedamagewithultrashortpulseisnonthermal,whichisdifferentfromthatwithlongpulse.Additionally,theablationcraterdepthsof45°high-reflectionfilmandinterferencefilterarepresented.Alogarithmicrelationbetweentheablationdepthandpulsefluence,whichissimilartothatoftransparentmaterials,isfound.

  • 标签: 毫秒激光器 多层断裂诱导 金薄膜 超短脉冲
  • 简介:因为免费表面旋涡吸收的空气在抽的系统上导致噪音,颤动,和成穴腐蚀,免费表面旋涡控制在一个泵池系统是重要的。在这研究,在泵吸入的免费表面旋涡和空气吸收的变化被部分(VOF)方法的体积与稳定的多相的流动模型一起调查了以便确切代表免费表面旋涡的行为。同类的免费表面模型被用来使用空气和水的相互作用。结果证明由免费表面旋涡运动的空气吸入能用空气体积部分的iso表面被设想。旋涡用免费表面做空气列到泵吸入。另外,免费表面旋涡能被安装窗帘墙控制,这被发现。

  • 标签: 自由表面 旋涡控制 数值模拟 诱导 进气道 泵送系统