简介：<正>Therewasoncean11-year-oldboywhowentfishingeverytimehewenttoanislandinthemiddleofaNewHampshirelake.Onthedaybeforebass(巴斯鱼)seasonopened,heandhisfather

简介：整个故事在情人节那天发展到了高潮。洛丽用白胶在卡片里信手拼出了非常漂亮的“我爱你”，并在上面洒了发光屑。我将这张卡片反反复复看了三、四十遍。然后把它藏到了短袜里……回到餐馆。我尽力用最纯洁的吻封好信封。将卡片放在我们的桌子上，然后默默地走了出去。

简介：Itwasafreezingday,whenIpickedupawalletinthestreet.TherewasnothinginsidebutaletterthatwassignedHelen.OnthetomenvelopeIfoundtheretumaddress,soIcalledanInformationline.Theoperatoraskedmetoholdon,andshecamebackon

简介：Anewopticalfiberfluorometricthermometerbasedonthetemperaturedependenceofthefluorescencelifetimeofphosphorisdescribed.Thephase-lockeddetection(PLD)systemisusedtomeasurefluorescencelifetime.Thecharacteristicsofthermmeterarediscussedandtheexperimentresultsaregiven.

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简介：Anovelfluorescencelifetimeimagingmicroscopy(FLIM)workingwithdeepUV240–280nmwavelengthexcitationshasbeendeveloped.UV-FLIMisusedformeasurementofdefect-relatedfluorescenceanditschangesuponannealingfromfemtosecondlaser-inducedmodificationsinfusedsilica.ThisFLIMtechniquecanbeusedwithmicrofluidicandbiosamplestocharacterizetemporalcharacteristicsoffluorescenceuponUVexcitation,acapabilityeasilyaddedtoastandardmicroscope-basedFLIM.UV-FLIMwastestedtoshowannealingofthedefectsinducedbysilicastructuringwithultrashortlaserpulses.Frequency-domainfluorescencemeasurementswereconvertedintothetimedomaintoextractlongfluorescencelifetimesfromdefectsinsilica.

简介：正电子歼灭一生光谱学(伙伴)是一种强大的技术在聚合物学习免费体积。ortho电子偶素(o-Ps)的一生，一个电子的一个界限状态和一个正电子，当紧张能被用来描绘毛孔的数字时，能被用来估计毛孔尺寸。(2,6-dimethyl-1,4-phenyleneoxide)(SPPO)根据在在sulfonated的一生系列，半径和部分免费体积的长寿o-Ps部件的价值，poly，有LiCl的不同数量的膜被计算。与LiCl的增加的数量，免费体积半径和部分免费体积第一增加了然后减少，这被发现。在在提取的水里沉浸膜以后，免费体积半径和部分免费体积在膜随着不同的水集中变化了。

简介：AIM:Toinvestigatethelifetimeriskofdevelopmentofesophagealadenocarcinomaand/orhigh-gradedysplasiainpatientsdiagnosedwithBarrett’sesophagus.METHODS:DatawereextractedfromtheUnitedKingdomNationalBarrett’sOesophagusRegistryondateofdiagnosis,patientageandgenderof7877patientsfromwhohadbeenregisteredfrom35UnitedKingdomcenters.LifeexpectancywasevaluatedfromUnitedKingdomNationalStatisticsdatabasedupongenderandageatyearatdiagnosis.Thesedatawerethenusedwithpublishedestimatesofannualadenocarcinomaandhigh-gradedysplasiaincidencesfrommetaanalysesandlargepopulation-basedstudiestoestimateoveralllifetimeriskofdevelopmentofthesestudyendpoints.RESULTS:ThemeanageatdiagnosisofBarrett’sesophaguswas61.6yearsinmalesand67.3yearsinfemales.Themeanlifeexpectancyatdiagnosiswas23.1yearsinmales,20.7yearsinfemalesand22.2yearsoverall.Usingdatafrompublishedmeta-analyses,thelifetimeriskofdevelopmentofadenocarcinomawasbetween1in8and1in14andthelifetimeriskofhigh-gradedysplasiaoradenocarcinomawas1in5to1in6.Usingdatafrom3largerecentpopulation-basedcohortstudiesthelifetimeriskofadenocarcinomawasbetween1in10and1in37andofthecombinedendpointofhigh-gradedysplasiaandadenocarcinomawasbetween1in8and1in20.AgeatBarrett’sesophagusdiagnosisisreducingandlifeexpectancyisincreasing,whichwillpartiallycounter-balancelowerannualcancerincidence.CONCLUSION:Thereisasignificantlifetimeriskofdevelopmentofhigh-gradedysplasiaandadenocarcinomainBarrett’sesophagus.

简介：Forthelargenumberofnonlineardegradationdevicesexistinginaproject,theexistingmethodshavenotsystematicallystudiedtheeffectsofrandomeffectontheremaininglifetime(RL),theaccuracyandefficiencyoftheparametersestimationarenothigh,andthecurrentdegradationstateofthetargetdeviceisnotaccuratelyestimated.Inthispaper,anonlinearWienerdegradationmodelwithrandomeffectisproposedandthecorrespondingprobabilitydensityfunction(PDF)ofthefirsthittingtime(FHT)isdeduced.Aparameterestimationmethodbasedonmodifiedexpectationmaximum(EM)algorithmisproposedtoobtaintheestimatedvalueoffixedcoefficientandthepriorivalueofrandomcoefficientinthemodel.Theposteriorvalueoftherandomcoefficientandthecurrentdegradationstateoftargetdeviceareupdatedsynchronouslybythestatespacemodel(SSM)andtheKalmanfilteralgorithm.ThePDFofRLwithrandomeffectisdeduced.AsimulationexampleisanalyzedtoverifythattheproposedmethodhastheobviousadvantageovertheexistingmethodsinparameterestimationerrorandRLpredictionaccuracy.

简介：Fluorescenceliftimeimaging(FLIM)ofmodifiedhydrophobicbodipydyesthatactasfluorescentmolecularrotorsshowsthatthefluorescencelifetimeoftheseprobesisafunctionofthemicroviscosityoftheirenvironment.Incubatingcellswiththesedyes,wefindapunctateandcontinuousdistributionofthedyeincells.Theviscosityvalueobtainedinwhatappearstobeendocytoticvesiclesinlivingcellsisaround100timeshigherthanthatofwaterandofcellularcytoplasm.Time-resolvedfluorescenceanisotropymeasurementsalsoyieldrotationalcorrelationtimesconsistentwithlargemicroviscosityvalues.Inthisway,wesuccessfullydevelopapracticalandversatileapproachtomapthemicroviscosityincellsbasedonimagingfluorescentmolecularrotors.

简介：TheinfluenceoftemperatureandGacompositiononAugerrecombinationlifetimeinn-typeandp-typeIn1-xGaxAsmaterialsisinvestigatedthroughthesimulation,assumingtheconcentrationsofelectronsandholesare1017cm-3and1018cm-3,respectively.TheresultsshowthatthetemperaturehaslittleinfluenceonAugerrecombinationlifetimeofIn1-xGaxAsmaterialsatx<0.3.However,ithasagreatimpactwhenx>0.3andtheeffectismoreobviousatalowertemperature.Moreover,Augerrecombinationlifetimeofp-typeIn1-xGaxAsislongerthanthatofn-typeIn1-xGaxAswiththesametemperature,Gacompositionandcarriersconcentration.

简介：Toestimatethelifetimeofpneumaticcylinderinmachinetool(orautomaticassemblyline),newreliabilitymethodologyforparametricacceleratedlifetesting(ALT)issuggested.ItconsistsofparametricALTplan,generalizedlife-stressfailuremodelwithaneweffortconcept,accelerationfactor,andsamplesizeequation.ThisnewparametricALTenablesanengineertoestimatethelifetimeofacommerciallypartsbyuncoveringthefailurethroughacceleratedtestingundersevereconditions.Asacasestudy,twocommercialproductsofthepneumaticcylinderinmachinetoolweretested.ForcompanyA,wefoundthehardeningandwearofpistonseallikethatoffieldatnormalconditions.Asincreasingthepressure,thepneumaticcylindersweretested.Basedontheacceleratedconditions—0.8MPaand1.2MPaat23℃,B1lifeat0.63MPaand23℃wasextrapolatedas2.39×10^6.Ontheotherhand,forcompanyB,wefoundtherodcapblockedbyslurrylikethoseoffieldsamples.Basedontheacceleratedconditions—0.8MPaand1.4MPaat23℃,B1lifeat0.63MPaand23℃wasextrapolatedas2.51×10^6.Comparingthemwithtestingdataatnormaluseconditions,weknewthattheestimationerrorforbothcompanieswaslessthan10%.

简介：Let{N(t),t≥0}bethenonhomogeneousPoissonprocesswithcumulativeintensityparameterΛ(t),{δt,t≥0}theageprocess,and{yi,t≥0)theresiduallifetimeprocess.Inthepresentpapertheexpressionsofn-dimensionalsurvivaldistributionfunctionsoftheprocesses{δi}and{yi},andtheirLebesguedecompositionsarederived.

简介：AbstractLuminescence (mostly fluorescence and phosphorescence) probes are a powerful tool widely used in the life sciences research. They can be used, for example, in the quantitative analysis of physiological parameters, visualization of different cell organelles, and measurement of drug transportation. The luminescence intensity and lifetime of these probes are among the main signals recorded and evaluated in these applications. Other reviews have discussed optical probes from the perspective of their luminescence intensity. However, the luminescence lifetime, which depends on the molecular microenvironment but not the probe concentration, is another promising metric for biological sensing and imaging applications. In this review, we aim to introduce the basic strategies of FLIM probe design. We also present applications of these probes, including sensing of intracellular pH, cation/anion concentrations, oxygen levels, biomolecule contents, and physiological parameters, as well as live-cell imaging based on luminescence lifetime. Studies based on FLIM imaging of cells or tissues with endogenous organic molecules are not included in this mini review. With the rapid development of microscopy technology for fluorescence lifetime imaging, fluorescence lifetime-based probes have shown great potential in a variety of biological applications.

简介：Thelifetimeofanartificialsatellitemovinginthecircularorbitundertheactionofnonuniformrotatingatmosphericdragisstudiedfromanenergypointofviewinthispaper.Theangularvelocityofatmosphericrotationdecreaseswithheightaccordingtohydrodynamics.Theatmosphericdensitydecreaseswithheightaccordingtotheexponentialformula.Theexpressionforthelifetimeofasatelliteintheinstantaneouscircularorbitintheabove-mentionedrotatingatmosphericmodelisderived,andthenumericalestimationforthelifetimeofaconcretesatellitehasbeenmade.Theresultshowsclearlythatthesatellitelifetimecalculatedbythispaperisshorterthanthatcalculatedbytheuniformrotatingatmosphericmodel.

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简介：Ｅｍｉｓｓｉｏｎ　Ｔｉｍｅ　ｏｆ　Ｌｉｇｈｔ　Ｐａｒｔｉｃｌｅｓ　ａｎｄ　Ｌｉｆｅｔｉｍｅ　ｏｆ　Ｈｏｔ　Ｎｕｃｌｅｉ　Ｆｏｌｌｏｗｉｎｇ　Ｂｉｎａｒｙ　ＦｉｓｓｉｏｎＥｍｉｓｓｉｏｎＴｉｍｅｏｆＬｉｇｈｔＰａｒｔｉｃｌｅｓａｎｄＬｉｆｅｔｉｍｅｏｆ...

简介：Wehavefoundthattheexcitedenergyfromthegroundstatewith1f7=2configurationtothefirstexcitedstatewith2p3=2configurationin37SisobviouslylowercomparedwiththatinnearbyN=21isotones35Si,39Arand41Ca(seeFig.1,Theinsertindicatestherelevantsingle-particleorbitsofprotonandneutron).ThisinterestingphenomenonmayresultfromthecollapseofN=28closure,whichgivesthesufficientvalencespaceforcollectivedeformationwhichcanbeenrevealedfromtheB(E2)value.Therefore,toobtaintheB(E2),weperformtheexperimentsformeasuringthelifetimeofthefirstexcitedstatein37S.

简介：Inthispaper,wehavediscussedarandomcensoringtestwithincompleteinformation,andprovedthatthemaximumlikelihoodestimator(MLE)oftheparameterbasedontherandomlycensoreddatawithincompleteinformationinthecaseoftheexponentialdistributionhasthestrongconsistency.

简介：从同样渗出的镁合金Mg-3%Al-1%Zn(AZ31)营舍准备的样品在低周期的疲劳测试被利用以便调查频率依赖者疲劳生活。充分颠倒的控制紧张的紧张压缩疲劳测试在空中在1Hz和10Hz的频率被执行。微观结构被光显微镜学(OM)和扫描电子显微镜学(SEM)检验。当紧张振幅比0.2%低时，疲劳生活与装载频率展出了积极关联，并且twinning的活动在10Hz被增加。当紧张振幅比0.2%高时，重要twinning在生活被发现独立于频率的这二频率，和疲劳被观察。为这频率相关的疲劳一生的可能的原因可能由于在装载频率和紧张振幅之上的twinning的依赖。