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500 个结果
  • 简介:ThethermalstabilityofNewZealandculturerabbitmusclealdolasewasinvestigatedbydifferentialscanningcalorimetryinthewatercontentrange0.23-3.70gwaterpergprotein.Theexperimentalresultsshowedthatatwatercontentsbelow0.47g/g,anendothermicpeakwasobservedandatwatercontentsabove0.57g/g,anendothermicandanexothermicpeakwerebothobservedonDSCthermogram.Thermaldenaturationresultoftheenzymeandtherelationshipbetweentwotransitiontemperaturesandwatercontentswerefirstreportedinthispaper.Uptonowwehavenotseenanysimilarreportsconcerningtheexothermictransition.

  • 标签: CALORIMETRY Zealand rabbit CHAINS concerning HYDRATION
  • 简介:ObjectiveToExplorethemechanismoftheacupunctureonposanenopausalosteoporo-sis.MethodOnehundredWistarfemalerats(6month-old)wererandomlydividedintotwogroups:O-variectomizedgroupandsham-operatedgroup.After3monthsofoperation,threeratswerechosentomeasurethebonehistomorphometricindexes.Thentheovariectomizedratsweredistributedrandomlytoacupuncturegroupandyigaininggroupandnormalsalinegroupandcontrol2group,theratswererespec-tivelytreatedbyacupunctureandyigainingandnormalsaline.Afterthetreatmentforthreecourse,allratswerecollectedbloodfromtheateriafemoralis,thelevelsofcalcitoninweremeasuredbyIRMA.thebonehistomorphometricindexesandC-cellinthyroidfollicleweredetected.ResultsThelevelsofcalcitoninofacupuncturegroupwereincreasingsignificantlycomparingwiththeyigaininggroupandthenormalsalinegroupandthecontrol2group(p<0.05),buttherewerenoevidentdifferenceinthelevelsofcal-citoninbetweentheacupuncturegroupandthesham-operatedgroup.Themeantrabecularbonewidthandthetmbecuharbonevolume%ofacupuncturegroupwereincreasingmorethanthatofthenormalsalinegroupandthecontrol2group(p<0.05);themeanmarrowcavitywidthandthemarrowcavityvol-ume%werederreasingmorethanthatofthenomalsalinegroupandthecontrol2group(P<0.05);thenumberofC-cellinthyroidfollicleoftheacupuncturegroupwereincreasingmorethanthatoftheothergroupsexceptthesham-operatedgroup.ConclusionAcupuncturecaneffectivelytreatthepost-menopausalosteoporosisbystrengtheningtheabilityoftheC-cellinthyroidfolliclewhichcanimprovethelevelsofcalcitonininserum.

  • 标签: 针刺疗法 降血钙素 绝经 骨质疏松 动物实验
  • 简介:Thispaperreviewsthestudiesonacoustoelectriceffectinextrinsicsemiconductormaterialsusedinvariousscientificandothermeasurements.Ahistoricalreviewofearlierfindingsisgivenwithspecialreferencetoassociatedmechanisms.Acoustoelectricstudiesinsolidstatedevioesrequirefurtherattentionandtheworkdoneinthisareaisalsodiscussed.

  • 标签: HISTORICAL EARLIER extreme EXTRINSIC MOMENTUM RELAXATION
  • 简介:Thecooperativeprincipleisanimportanttheoryofpragmatics,concerninghowtomaximallyachievecommunicativegoal.Whiletranslationservesasacommunicativemedium,itshouldalsoobservetheconversationalrules—cooperativeprincipletoachievetheequivalenteffect.Thispapertriestoexploretheissuefromtheperspectiveofcooperativeprinciple.

  • 标签: TRANSLATION COOPERATIVE PRINCIPLE EQUIVALENT effec
  • 简介:Withdevelopmentofmoderngeoscience,particularlydevelopmentofenvironmentalsciences,thecontemporarysoilscienceisundergoinggreatchangesinbothresearchcontentsandscope.Soilisnotonlyacertainsubstanceoracertainindependentnaturalhistoricalbodybutalsoasphericlayerwithpeculiarstructureandfunctionsintheearthsystem.Fromtheviewpointofthegeo-biospheresystemofearth,soilsciencedoesdealnotonlywiththesoilsubstancespersebutalsomoreimportantlywiththerelationshipsamongsoil,theotherspheresandthehumansurvivalenvironmentinviewofthe"pedosphere",Thisistheneworientationofsoilsciencetodayandwillaffectprofoundlythestudiesonthehumansurvivalenvironmentandglobalchanges,Tothrowmorelightonthissubject,thepresentpaperintendstoaddresstheconceptionofpedosphereanditsroleinglobalchanges,AlsoaddressedareseriesofenvironmentalissuesinChinaandtheirrelationstotheglobalchanges.Moreover,researchorientationandprioritiesareindicated,includingexploitationandprotectionofthesoilresources,soilfertilityandsustainableagriculturaldevelopment,constructionoftheecologicalenvironment,andthematerialcyclinginpedosphereanditsrelationtoglobalchanges.

  • 标签: 生态环境 全球变化 土壤圈 土壤学 地球 物质循环
  • 简介:Thethermodynamicpropertiesofcrystalscanberoutinelycalculatedbydensityfunctionaltheorycalculationscombiningwithquasi-harmonicapproximation.BasedonthemethoddevelopedrecentlybyWuandWentzcovitch(PhysRevB79:104304,2009)andWu(PhysRevB81:172301,2010),weareabletofurtherabinitioincludeanharmoniceffectonthermodynamicpropertiesofcrystalsbyoneadditionalcanonicalensemblewithnumbersofparticle,volumeandtemperaturefixed(NVT)moleculardynamicsimulations.Ourstudyindicatesthatphonon–phononinteractioncausestherenormalizedphononfrequenciesofwadsleyitedecreasewithtemperature.ThisisconsistentwiththeRamanexperimentalobservation.TheanharmonicfreeenergyofwadsleyiteisnegativeanditsheatcapacityatconstantpressurecanexceedtheDulong–Petitlimitathightemperature.Theanharmonicitystillsignificantlyaffectsthermodynamicpropertiesofwadsleyiteatpressureandtemperatureconditionscorrespondtothetransitionzone.

  • 标签: wadsleyite 热力学性质 非谐效应 密度泛函理论 声子频率 分子动力学
  • 简介:masker与maskee的理论分析和实验是空间的在方位角的分离证明当masker和maskee空间地被分开时,阀值趋于到落下和空间揭露的producethe现象。结果也证明空间揭露与频率有关。频率越高,空间揭露是越多stronger。最大的揭露是15dB。主要暗示是masker和maskee什么时候采购原料,空间地在方位角被分开,因为头的影响,单耳的Signal-to-Mask比率(SMR)将增加相关转移功能(HRTF)。同时,由更高听觉的系统的听觉的信息的有两耳的处理是空间揭露的另一个原因。

  • 标签: 实验性学习 空间掩码 理论分析 声学分析
  • 简介:IntheprocessofsolvingEulervectorsbasedonGNSShorizontalmovementfield,thenumberofestimatedparameterscanaffectEulervectorresults.Thisissueisanalyzedthroughtheoreticaldeductionandpracticalexampleinthispaper.Firstly,thedifferencebetweentheresultsofEulervectorsindifferentsolvingmodelsisdeduced.Meanwhile,basedonGNSShorizontalmovementfieldintheChinesemainlandfrom2004to2007,twocommonmodels(RRMandREHSM)areusedtodiscusstheimpactofsolvingmodelsonEulervectorsandthefollow-upstudy.Theresultshowsthatthemaximumvalueofthedifferenceinablock’sentirerotationcanreach2.6mm/a,andshouldnotbeignored.Therefore,theresultsofhorizontalmovementaredifferentusingdifferentkinematicblockmodels,andthisshouldbepaidmoreattentionintheanalysisofcrustalhorizontalmovement.

  • 标签: 欧拉矢量 求解模型 向量 地壳水平运动 全球导航卫星系统 水平移动
  • 简介:<正>Geodynamiccompositeeffectprinciplewhichisproducedonthebasisofearthmovementisabasictheoryofmechanics.Itbelongstoanewviewpointandconcept.Comparedwithgravityeffectofgeocentrictheory,anideologicalsystemofmechanicstakingthesunasreferencecoordinateispresentedtoexplaineasilynaturalphenomenaandprob-lemswhichgoagainstgravityeffect:volcano,earthquake,horizontalstress,magmaticactivityandcrustalmovement.Itcanbewidelyusedingeology,mining,engineering,geologicdisaster…Themainconclu-sionanddeductionareasfollows.

  • 标签: 三七
  • 简介:Theeffectofthermalcyclingunderloadingonmartensitictransformationandtwo-wayshapememoryeffectwasinvestigatedforTi-49.8at.pctNialloy.ItisshownthatMsandMftemperatureincreasewithincreasingthenumberofcycles,whileAsandAftemperaturedecreaseduringthermalcycling.Thetotalstrainεtandpermanentstrainεpincreasewithincreasingappliedstressandnumberofcycles.Thetwo-wayshapememoryeffectcanbeimprovedbyproperthermalcyclingtrainingunderloading,whileexcessivelyhighappliedstressresultsinthedeteriorationofTWSME.Thereasonforthechangesinmartensitictransformationcharacteristicsandtwo-wayshapememoryeffectduringthermalcyclingunderloadingisdiscussedbasedontheanalysisofmicrostructurebyTEMobservations.

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  • 简介:Objective:Toinvestigateimmune-relatedgeneticbackgroundinbilateralsuddensensorineuralhearingloss(SSNHL).Casereportandmethods:Thecaseisa45-year-oldmanpresentingwitha7-yearhistoryofbilateralprofoundSSNHL.Bloodbiochemicaltestingdemonstratedincreasedlevelsoftotalcholesterol(5.88mmol/L).TestsforhepatitisBshowedapositiveantibodyagainstthehepatitisBcoreantigen.ComplementC3wasbelowthenormalvalue,andcomplementC4andIgGwereinthelowerrangeofnormalvalues.CTimagesshowedanormalinnerearandvestibularaqueductbutroundwindowmembranousossificationonbothsides.Atotalnumberof232immuneassociatedgenesweresequencedusingthenextgenerationsequencingtechnique.Results:Mutationsweredetectedin5genes,includingthephosphoinositide3-kinasecatalyticsubunitdelta(PIK3CD),caspaserecruitmentdomain-containingprotein9(CARD9),complementfactorH-related(CFHR2),immunoglobulinlambda-likepolypeptide1Protein(IGLL1),andtransmembranechannel-likegenefamily8(TMC8).InthePIK3CDgene,aC896Tsubstituteinexon7wasdetected.Thismutationcausesprimaryimmunodeficiencyandisanautosomaldominantdisease.Conclusion:ThePIK3CDC896TmutationresponsibleforprimaryimmunodeficiencymaycontributetotheonsetofbilateralSSNHLwithsubsequentrapidprogression.

  • 标签: SUDDEN SENSORINEURAL HEARING loss IMMUNOLOGY Genetics
  • 简介:VertebrategenomesarecharacterizedwithCpGdeficiency,particularlyforGC-poorregions.TheGCcontent-relatedCpGdeficiencyisprobablycausedbycontext-dependentdeaminationofmethylatedCpGsites.ThishypothesiswasexaminedinthisstudybycomparingnucleotidefrequenciesatCpGflankingpo-sitionsamonginvertebrateandvertebrategenomes.Thefindingisatransitionofnucleotidepreferenceof5'Tto5'Aattheinvertebrate-vertebrateboundary,indi-catingthatalargenumberofCpGsiteswith5TsweredepletedbecauseofglobalDNAmethylationdevelopedinvertebrates.Atgenomelevel,weinvestigatedCpGobserved/expected(obs/exp)valuesin500bpfragments,andfoundthathigherCpGobs/expvalueisshowninGC-poorregionsofinvertebrategenomes(exceptseaurchin)butinGC-richsequencesofvertebrategenomes.WenextcomparedGCcontentatCpGflankingpositionswithgenomicaverage,showingthattheGCcontentislowerthantheaverageininvertebrategenomes,buthigherthanthatinvertebrategenomes.Theseresultsindicatethatalthough5'Tand5'AaredifferentininducingdeaminationofmethylatedCpGsites,GCcontentisevenmoreimportantinaffectingthedeaminationrate.Inallthetests,theresultsofseaurchinaresimilartovertebratesperhapsduetoitsfractionalDNAmethylation.CpGdeficiencyisthereforesuggestedtobemainlyaresultofhighmutationratesofmethylatedCpGsitesinGC-poorregions.

  • 标签: DNA甲基化 无脊椎动物 比较基因组 CPG基序 GC含量 网站
  • 简介:Themainrequirementsforbatteryseparatorsarehighporositywhichcanservepathwaysoflithiumionandspaceforgelelectrolytestoimpregnateinamembraneandmechanicalstrengthtoalloweasyhandlingforbatteryassembly.Generally,itappearsthetrade-offrelationshipbetweentheporosityandmechanicalstrengthofthemembrane.PVdFcompositemembranescontainingnano-sizeclayswereusedtoimprovethemechanicalstrengthofthemembranewithoutaffectingthemembraneporosity.Thecompositemembraneswerepreparedbyphaseinversionmethodcontrollingthemembranepreparationconditionssuchasretentiontime.Theresultantmembranesshowincreasedmechanicalpropertieswithsimilarmembraneporosityaround80%comparedtothepristinePVdFmembrane.Incorporationofnonoclaycanbeconsideredasaneffectivemethodtoimprovethemechanicalstrengthinporousmembranesupports,especiallyinaseparator.

  • 标签: 聚偏氟乙烯膜 机械性能 多孔膜 纳米粘土 机械强度 高孔隙率
  • 简介:Thispaperanalysestheoreticallytheeffectoftransportationandhousingsubsidiesonurbansprawl,modalchoicedecisionsandurbanspatialstructureusingaspatialgeneralequilibriummodelinamonocentriccitywithtwotransportmodes.Ouranalysisshowsthatpublictransitsubsidyleadstourbanshrink,whilstsubsidizingautomobileandhousingmakethecitysprawl.Wealsofindtheeffectsoftheotherfactorsonurbansprawl,suchashouseholdsincomeanddemand,rurallandrent,theincometaxrate,thetotalfixedcostofpublictransitandautomobileandthetravellingmarginalcostofpublictransitandautomobile.Furthermore,thispaperalsostudieshowtomaximizetheurban-area-widespatialequilibriumutilitylevel.

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  • 简介:Samplesofpolyphenylsilsisquioxane(PPSQ)usingCaF2orMgF2asthemaincatalystshadbeenpreparedunderdifferentpolymerizationconditions.TheresultsweretreatedonanorthogonaldesignL9(34).Allweight-averagemolecularweights(MW)ofPPSQhadbeenmeasuredbygelpermeationchromatography(GPC).Effectsofpolymerizationconditionsincludingreactiontemperature,compositionofthedualcatalysts(CaF2orMgF2andDCC),mixtureofsolventsandreactiontimeonMWofPPSQhavebeendiscussed.ThequantityofthecatalystsisthemostimportantfactorthataffectsMWofPPSQ.Reactiontemperatureisthesecondimportantfactor.AppropriatepolymerizationconditionhasbeenestablishedtogetPPSQwithhighMW.

  • 标签: Polyphenylsilsisquioxane POLYMERIZATION CONDITIONS MOLECULAR WEIGHT
  • 简介:一个城市的边界层模型(UBLM)被合并大楼的效果与改进一部分拖系数和一顶高度分布式的华盖拖长度规模。改进UBLM被使用与不同height-to-width比率在北京区域上在三典型的城市的块上模仿风地。为比较,在一样的块上的风地被明确地解决大楼的一个城市的子域规模模型模仿。从二个不同方法模仿的风地在好同意。然后,为北京的二维的造的词法特征和城市的华盖参数从造高度数据详细说明被导出。最后,experiements被进行用改进UBLM在北京在风地上调查大楼的效果。

  • 标签: 建筑物高度 北京地区 形态特征 风场模拟 城市街区 边界层模式
  • 简介:Theeffectofdifferentkindsofcomonomerswithorwithoutflexiblechainonproper-tiesofcopolyesters,suchastransitiontemperature,crystallizationvelocity,crystallinityandsizeofcrystallites,isstudied.Theexperimentalresultsindicatetheobviousdiffer-enceinpropertiesbetweencomonomerswithiso-andortho-structureofphenylringandcomonomerswithflexiblechain.Theinfluenceofchemicalstructureofcomonomersonpropertiesofcopolyestersisdiscussed.

  • 标签: COPOLYESTERS POLYETHYLENETEREPHTHALATE COMONOMER CHEMICAL STRUCTURE