简介:Basedon3DBiot’sconsolidationtheoryandnonlinearDuncan-Chang’smodel,a3DFEM(finiteelementmethod)programisdevelopedconsideringthecouplingofgroundwaterseepageandsoilskeletondeformationduringexcavation.Thecomparisonbetweentheanalysisresultconsideringthevariationofwaterheaddifferenceandthatwithoutconsideringitshowsthattheporewaterpressuredistributionoftheformerisdistinctlydifferentfromthatofthelatterandthatthefoundationpitde-formationsoftheformerarelargerthanthoseofthelatter,sothattheresultwithoutconsideringthevariationofwaterheaddif-ferenceisunreliable.Thedistributionrulesofsoilhorizontalandverticaldisplacementsaroundthepitandexcessporewaterpressureareanalyzedindetailintimeandspace,whichisverysignificantforguidingundergroundengineeringconstructionandensuringenvironmentsafetyaroundthepit.
简介:Anewtypeofelectrochemicaloscillationinducedbysurfactantwasobservedinexperiments.TheelectrochemicalsystemisaDaniellcellwithacopperrodinCuSO4aqueousandanaluminumrodinAl(NO3)3aqueousaselectrodes.ThesurfactantsareCTAB,TX-100,SLS.Theadditionoftracesurfactantsolutionbyamicro-syringemadetheoriginalmonotonouslychangingelectrochemicalsystemproduceobviousperiodicphenomena.Atthemeantime,thecopperionselectiveelectrodeandHg2SO4referenceelectrodewereusedtomonitorthecopperelectrodereactionanddetermineitsrateconstantkoffirstorderreaction.Accordingtotheexperimentalresultsofelectrodereactionkinetics,thepossiblemechanismwasfoundtobethepolarizationinducedfromthedirectionaladsorptionoftracesurfactantontheelectrodesurface.Thatistheelectrochemicaloscillations.
简介:K.J.,K.W. and K.R. Lees,we determined whether isoflurane preconditioning reduced glutamate receptor over-stimulation-induced neuronal death. Our results showed that isoflurane preconditioning reduced the neuronal death caused by over-stimulation of the major glutamate receptors [12]. Kapinya et al should be credited as the first group to show that isoflurane preconditioning induced a delayed phase of neuroprotection [13]. Our in vivo study showed that this protection was mediated by the activation of the mitogen-activated protein kinase p38 [14]. The isoflurane preconditioning-induced protection in human neuroblastoma SH-SY5Y cells involved the extracellular signal-regulated kinase-early growth response gene 1-Bcl-2 pathway activation [15]. Our in vivo study also showed that isoflurane preconditioning induced a delayed phase of protection in immature brains [16]. This protection was sustained even when animals were examined at one month after the brain ischemia [17]. In summary
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简介:Asimulationiscarriedoutforthepressurefluctuationdrivenbythewaterhammer,basedonajointuseoftheonedimensionalmethodofcharacteristics(MOC)andthethree-dimensionalfinitevolumemethod(FVM).Thethree-dimensionalvisualizationofthecavitationinducedbythewaterhammerisimplemented,andthetemporalandspatialanalysesofextremeregionsaremade.Apracticalcaseofthewaterhammer,withtheminimumboundarypressurehigherthanthesaturatedvaporpressurecondition,issimulated.Thesimulationpredictionthatthecavitationwouldoccurinthefrontofthegasketcouldservesomeguidelinefortheoptimizationofindustrialdesigns.
简介:ThisarticlepresentstheresultsofanumericalsimulationonthevortexinducedvibrationofvariousfinnedcylindersatlowReynoldsnumber.Thenon-dimensional,incompressibleNavier-Stokesequationsandcontinuityequationwereadoptedtosimulatethefluidaroundthecylinder.Thecylinder(withorwithoutfins)influidflowwasapproximatedasamass-springsystem.Thefluid-bodyinteractionofthecylinderwithfinsanduniformflowwasnumericallysimulatedbyapplyingthedisplacementandstressiterativecomputationonthefluid-bodyinterfaces.Bothvortexstructuresandresponseamplitudesofcylinderswithvariousarrangementsoffinswereanalyzedanddiscussed.TheremarkabledecreaseofresponseamplitudefortheadditionsofTriangle60finsandQuadrangle45finswasfoundtobecomparablewiththatofbarecylinder.However,theadditionsofTriangle00finsandQuadrangle00finsenhancetheresponseamplitudegreatly.Despitetheassumptionoftwo-dimensionallaminarflow,thepresentstudycangiveagoodinsightintothephenomenaofcylinderswithvariousarrangementsoffins.
简介:Weisolatedandpurifiedmitochondriafrommouseliversandspinachleaves.WhenaddedintoeggextractsofXenopuslaevis,theycausednucleiofmouselivertoundergoapoptoticchanges.Chromatincondensation,marginationandDNAladderwereobserved.Afterincubatingisolatedmitochondriainsomehypotonicsolutions,andcentrifugingthesemixturesatmghspeed,wegotmitochondrialsupernatants.Itwasfoundthatintheabsenceofcytosolicfactor,thesupernatantalonewasabletoinduceapoptoticchangesinnuclei.Theeffectivecomponentswerepartlyofprotein.DNAfragmentationwaspartlyinhibitedbycaspaseinhibitorsAC-DEVD-CHOandAC-YVAD-CHO.Meanwhile,caspaseinhibitorsfullyblockedchromatincondensation.Primarycharacterizationofthenuclearendonuclease(s)inducedbymitochondrialsupernatantswasalsoconducted.ItwasfoundthatthisendonucleaseisdifferentfromendonucleaseG,cytochromec-inducednuclease,orCa^2+-activatedendonuclease.
简介:Westudyoptomechanicallyinducedtransparencyinaspinningmicroresonator.Wefindthatinthepresenceofrotation-inducedSagnacfrequencyshift,boththetransmissionrateandthegroupdelayofthesignalarestronglyaffected,leadingtoaFano-likespectrumoftransparency.Inparticular,tuningtherotaryspeedleadstotheemergenceofnonreciprocalopticalsidebands.Thisindicatesapromisingnewwaytocontrolhybridlight–sounddeviceswithspinningresonators.
简介:Alaboratoryexperimentwasconductedinsideawindwavetanktoinvestigatethewaveinducedturbulence.Inthisexperiment,thewavesurfaceelevationandvelocitybeneaththewatersurfaceweremeasuredsimultaneouslytoinvestigatetherelationbetweenthewavestatusandwaveinducedturbulence.TheprofileoftheturbulentdissipationrateandReynoldsstresswerecalculatedusingexperimentaldata.Theeffectofthewavestatusonturbulenceisinvestigatedwithregardtothewindwave,swell,andmixedwaveconditions.Itwasdepictedthattheturbulencedecreasedwithincreasingdepthfromthewatersurfaceandthattheturbulencethatwasinducedbyawavewithlargerwavelengthandwaveheightismuchstrongerforthesamewavestatus.Finally,weobservedthatthewindwaveismoreeffectiveinactivatingthewaveinducedturbulence.
简介:Moleculardynamics(MD)simulationsoftheconsecutivecompression-decompressioncyclesofhexagonalzincsulfide(wurtzite)nanoparticlespredictanirreversiblephasetransformationtothecubicpolymorph.Thephasetransformationcommencesatthecontactareabetweentheparticleandtheindenterandproceedswiththenumberofcompressioncycles.Dislocationsarevisibleforaparticlesizeabove5nm.ResultsfromwetgrindinganddrypowdercompressionexperimentsonacommercialwurtzitepigmentagreequalitativelywithMDsimulationpredictions.X-raydiffractionpatternsrevealthattheamountofcubicpolymorphinthecompressedsamplesincreaseswithpressureappliedtothepowder.Incomparisonwithpowdercompression,wetmillingleadstoamorepronouncedphasetransformation.Thisoccursbecausetheparticlesareexposedtoalargenumberofstresseventsbycollisionwiththegrindingmedia,whichleadstotheformationofdefectsandnewsurfacecrystallitesbyparticlefracture.AccordingtotheMDsimulations,phasetransformationisexpectedtooccurpreferentiallyinsurfacecrystallitesbecausetheyexperiencethehighestmechanicalload.Becauseofthephasetransformation,thewetgroundandcompressedsamplesexhibitalowerphotoluminescenceintensitythanthefeedmaterial.Incomparisonwithpowdercompression,millingreducesthephotoluminescenceintensitymoresubstantially.Thisoccursbecauseahigherdefectconcentrationisformed.Thedefectscontributetothephasetransformationandphotoluminescencequenching.
简介:LetGbeasecondcountablelocallycompactgroupoidwithHaarsystem{λuH},HbeaclosedsubgroupoidcontainingG^0withHaarsystem{λuH}.T.MasudaintroducedtheC^*-Groupoiddynamicsystem(G,A,α)anditsreducedcrossedproductCrea(G,A)in[2]:whereAisC^*-algebraαisthekomomorphismG→Aut(A).InthispapertheauthorintroducestheC^*-groupoiddynamicsystems(H,A,α/H)and(H\G2,A,^-α)inducedby(G,A,α)andprovesthatC*red(H,A)andC^*red(H\G^2,A)arestronglyMoritaequivalentMoreovertheinducedrepresentationfromC^*red(H,A)toC^*red(G,A)isgot.
简介:YagerpresentedtheOrderedWeightedAveraging(OWA)operatortoprovideamethodforaggregatinginformationofdecision-making.YagerandFilevfurtherpresentedtheInducedOrderedWeightedAveraging(IOWA)operator.Inthispaper,weproposeaGeneralizedInducedOrderedWeightedGeometric(GIOWG)operatorandestablishasimpleobjective-programmingmodeltolearntheassociatedweightingvectorfromobservationaldata.EachobjectprocessedbytheGIOWGoperatorconsistsofthreecomponents,wherethefirstcomponentrepresentstheimportancedegreeorcharacterofthesecondcomponent,andthesecondcomponentisusedtoinduceanordering,throughthefirstcomponent,overthethirdcomponentswhicharethenaggregated.Thedesirableproperties,suchascommutativity,idempotencyandmonotonicity,etc.,associatedwlththeGIOWGoperatorarestudiedindetail,andsomenumericalexamplesaregiventoshowthepracticalityandeffectivenessofthedevelopedoperator.
简介:volatile anesthetics can induce acute and delayed phases of preconditioning effects in the brain. Since isoflurane is a relatively safe agent and has been frequently used in patients with potential brain ischemia,7]. We showed for the first time that preconditioning with the volatile anesthetic isoflurane induced an acute phase of neuroprotection [8]. Our subsequent study showed that this isoflurane preconditioning-induced acute phase of neuroprotection was dose-dependent with an EC50 1.17% and that preconditioning the brain with isoflurane for 15-30 min was needed for the preconditioning to be maximally protective. This effect was glutamate transporter-dependent [9]. Other volatile anesthetics,we determined whether isoflurane preconditioning reduced glutamate receptor over-stimulation-induced neuronal death. Our results showed that isoflurane preconditioning reduced the neuronal death caused by over-stimulation of the major glutamate receptors [12]. Kapinya et al should be credited as the first group to show that isoflurane preconditioning induced a delayed phase of neuroprotection [13]. Our in vivo study showed that this protection was mediated by the activation of the mitogen-activated protein kinase p38 [14]. The isoflurane preconditioning-induced protection in human neuroblastoma SH-SY5Y cells involved the extracellular signal-regulated kinase-early growth response gene 1-Bcl-2 pathway activation [15]. Our in vivo study also showed that isoflurane preconditioning induced a delayed phase of protection in immature brains [16]. This protection was sustained even when animals were examined at one month after the brain ischemia [17]. In summary
简介:AbstractBackground:The detrimental outcomes of right ventricular pacing on left ventricular electromechanical function ultimately result in heart failure, a phenomenon termed pacing-induced cardiomyopathy (PICM) in clinical research. This study aimed to validate prognostic factors that can be used to identify patients with higher susceptibility to progress to the stage of cardiomyopathy before pacemaker implantation.Methods:This observational analysis enrolled 256 patients between January 2013 and June 2016, 23 (8.98%) of whom progressed to PICM after 1 year of follow-up. A Cox proportional hazard model was used to analyze the prognostic factors associated with PICM. Dose-response analysis was used to evaluate the relationship between significant indicators in multifactor analysis and PICM.Results:The mean values of left ventricular ejection fraction before and after pacemaker implantation in 23 patients diagnosed with PICM were 62.3% and 42.7%, respectively. Univariate analysis showed that sex, atrio-ventricular block, paced QRS duration, and ventricular pacing percentage were significantly associated with PICM. In the multivariate analysis, male sex (hazard ratio: 1.20, 95% confidence interval [CI]: 1.09-1.33, P < 0.005), paced QRS duration (hazard ratio: 1.95 per 1 ms increase, 95% CI: 1.80-2.12, P < 0.001), and ventricular pacing percentage (hazard ratio: 1.65 per 1% increase, 95% CI: 1.51-1.79, P < 0.001) were independent prognostic factors associated with the development of PICM. The ventricular pacing percentage and paced QRS duration level defined by the dose-response analysis were positively associated with PICM (P < 0.05).Conclusions:Our findings indicated that paced QRS duration and ventricular pacing percentage were the most sensitive prognostic factors for PICM.
简介:Trimethyltin(TMT)isanoccupationalandenvironmentalhealthhazardbehavingasapotentneurotoxinknowntoaffectthecentralnervoussystemaswellastheperipheralauditorysystem.However,themechanismsunderlyingTMT-inducedototoxicityarepoorlyunderstood.ToelucidatetheeffectsofTMTonthecochlea,asingleinjectionof4or8mg/kgTMTwasadministeredintraperitoneallytoadultrats.Thecompoundactionpotential(CAP)thresholdwasusedtoassessthefunctionalstatusofthecochleaandhistologicaltechniqueswereusedtoassesstheconditionofthehaircellsandauditorynervefibers.TMTat4mg/kgproducedatemporaryCAPthresholdelevationof25-60dBthatrecoveredby28dpost-treatment.Althoughtherewasnohaircelllosswiththe4mg/kgdose,therewasanoticeablelossofauditorynervefibersparticularlybeneaththeinnerhaircells.TMTat8mg/kgproducedalargepermanentCAPthresholdshiftthatwasgreatestatthehighfrequencies.TheCAPthresholdshiftwasassociatedwiththelossofouterhaircellsandinnerhaircellsinthebasal,high-frequencyregionofthecochlea,considerablelossofauditorynervefibersandasignificantlossofspiralganglionneuronsinthebasalturn.Spiralganglionneuronsshowedevidenceofsomashrinkageandnuclearcondensationandfragmentation,morphologicalfeaturesofapoptoticcelldeath.TMT-induceddamagewasgreatestinthehigh-frequency,basalregionofthecochleaandthenervefibersbeneaththeinnerhaircellswerethemostvulnerablestructures.
简介:Basedontheself-excitedvibrationtheoryofice,thevibrationcontroltechnologyofjacketplatformisstudiedinthispaper.Themagnetorheologicalsuspensions(MR)unitischosenasthedamper,thecontrolobjectivefunctionforvibrationexcitedbyiceisdeterminedbyinstantaneousoptimalcontrol(IOC)method,andgeneticalgorithm(GA)isusedtoselecttheoptimalcontrolforce.Forthejacketplatformof40minheightanda3-floordeck,thevibrationresponsesinducedbyicehavebeencalculatedbeforeandaftercontrolconsideringthedifferentthicknessandspeedofice.Itisshownthatthecontrolmethodpresentedinthispapercanreducethevibrationresponseby30%,anditisfeasibletoadoptMRabsorberandGAinthecontrolofvibrationinducedbyice.