学科分类
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434 个结果
  • 简介:-BasedontheextendedMorisonEquationandmodeltests,thein-lineforcesonsmallsquarecylinderscausedbywaves(regularandirregular)andcurrentsareanalyzedindetailinthispaper.ThehydrodynamiccoefficientCDandCurelatedtoKCnumberandtheeffectofdirectionofwaveincidencearealsogiven,whichcanbeusedinengineeringpractice.

  • 标签: wave FORCES SMALL CYLINDER Morison EQUATION
  • 简介:假定G是有最大的度的一张平面图。在它被证明那G的这份报纸是全部的--(+2)-choosable如果(1)7并且G没有邻近的三角形(即,没有二个三角形是有一个普通的边的事件);或(2)6并且G没有交叉三角形(即,没有二个三角形是有一个普通顶点的事件);或(3)5,G没有邻近的三角形,G没为某整数k有k周期{5,6}。

  • 标签: 平面图形 三角形 全染色 距离 名单 不相交
  • 简介:Atheoreticalstudywasconductedtocharacterizehydraulicjumpoflaminarcircularliquidjets.Theobjectiveofthisresearchwastodeterminethejumplocationinasimpleexplicitform,Theeffectsofmanyfactorswereinvestigatedincludingnozzlediameter,jetexitpressure,nozzle-to-platespacing,jetvelocityandReynoldsnumber,ItwasfoundthatthetheoreticaldatacollapsedwellovertherangeofjetReynoldsnumber500≤Re≤1800withpreviousdata.

  • 标签: 液体喷射 水力突增 对流热传输
  • 简介:Tworecentstudieshavediscoveredasurprisinglinkbetweenthreeseeminglydifferentclinicaldiseases:onethatdestroysbonemarrow,anotherthatpreventssundamagefrombeingrepaired,andathirdwhichcauseschildrentoshowsignsofagingextremelyearly.Ithasbeenfoundthatallthreediseasesarecausedbymutationsinthesamegene.Mutationscomeinanumberofdifferentflavors,

  • 标签: 临床疾病 基因 点突变 早期老化 DNA 骨髓
  • 简介:AbstractBackground:Homozygous or compound heterozygous mutations in high temperature requirement serine peptidase A1 (HTRA1) gene are responsible for cerebral autosomal recessive arteriopathy with subcortical infarcts and leukoencephalopathy (CARASIL). Recently, increasing evidence has shown that heterozygous HTRA1 mutations are also associated with cerebral small vessel disease (CSVD) with an autosomal dominant pattern of inheritance. This study was aimed to analyze the genetic and clinical characteristics of HTRA1-related autosomal dominant CSVD.Methods:We presented three new Chinese cases of familial CSVD with heterozygous HTRA1 mutations and reviewed all clinical case reports and articles on HTRA1-related autosomal dominant CSVD included in PUBMED by the end of March 1, 2020. CARASIL probands with genetic diagnosis reported to date were also reviewed. The genetic and clinical characteristics of HTRA1-related autosomal dominant CSVD were summarized and analyzed by comparing with CARASIL.Results:Forty-four HTRA1-related autosomal dominant CSVD probands and 22 CARASIL probands were included. Compared with typical CARASIL, HTRA1-related autosomal dominant probands has a higher proportion of vascular risk factors (P < 0.001), a later onset age (P < 0.001), and a relatively slower clinical progression. Alopecia and spondylosis can be observed, but less than those in the typical CARASIL. Thirty-five heterozygous mutations in HTRA1 were reported, most of which were missense mutations. Amino acids located close to amino acids 250-300 were most frequently affected, followed by these located near 150∼200. While amino acids 250∼300 were also the most frequently affected region in CARASIL patients, fewer mutations precede the 200th amino acids were detected, especially in the Kazal-type serine protease domain.Conclusions:HTRA1-related autosomal dominant CSVD is present as a mild phenotype of CARASIL. The trend of regional concentration of mutation sites may be related to the concentration of key sites in these regions which are responsible for pathogenesis of HTRA1-related autosomal dominant CSVD.

  • 标签: CARASIL Cerebral small vessel disease Heterozygous mutation HTRA1
  • 简介:Sincethefailureoftraditionaltherapy,genetherapyusingfunctionalDNAsequenceandsmallRNA/DNAmolecules(oligonucleotide)hasbecomeapromisingavenueforcancertreatment.ThediscoveryofRNAmoleculeshasimpelledresearcherstoinvestigatesmallregulatoryRNAfromvariousnaturalandartificialsourcesanddetermineacogenttargetforcontrollingtumorprogression.SmallregulatoryRNAsareusedfortherapeuticsilencingofoncogenesandaberrantDNArepairresponsegenes.Despitetheiradvantages,therapiesbasedonsmallRNAsexhibitlimitationsintermsofstabilityoftherapeuticdrugs,precisionbaseddeliveryintissues,precision-basedintercellularandintracellulartargeting,andtumorheterogeneity-basedresponses.Inthisstudy,wesummarizethepotentialanddrawbacksofsmallRNAsinnucleicacidtherapeuticsforcancer.

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  • 简介:Inthisarticle,werelocatedtheseismicsourcelocationoftheearthquakesintheMuliareaofSichuan,invertedthefocalmechanismofthelargerearthquakesandanalyzedtherelationshipbetweenthewaterleveloftheJinpingreservoirandthefrequencyoftheearthquakeswarm.Theresultsshowthat:(1)Theepicentersoftherelocatedsmallearthquakeswarmsaredistributedinaseismiczone,andtheearthquakefocaldepthswereintherangeof0-12km.(2)Byanalyzingtheearthquakeswarmspatialdistribution,wefoundthattheswarmsweregeneratedbyonebranchfaultonthewestofXiaojinhefault.(3)Thefocalmechanismofthethreeearthquakeswithmagnitudegreaterthan4.0issignificantlydifferent,withtheshallowsourcethrusteventsaffectedbyverticalstress,andthestrike-slipeventsarerelatedtoregionalstresstectonicactivity.

  • 标签: 小震群 四川省 活动特征 木里 地震空间分布 震源机制
  • 简介:AIM:Toclarifythecorrelationwithphenotypicexpression,clinicopathologicalfeatures,geneticalterationandmicrosatellite-instabilitystatusinsmallintestinaladenocarcinoma(SIA).METHODS:Thecasesof47patientsdiagnosedwithprimarySIAsthatweresurgicallyresectedatourinstitutionin1975-2005werestudied.Wereviewedclinicopathologicalfindings(age,gender,tumorsize,grossappearance,histologicalmorphologictype,invasiondepth,lymphaticpermeation,venousinvasion,andlymphnodemetastasis),andtheimmunohistochemicalexpressionofMUC5AC,MUC6,MUC2,CD10,andmismatch-repair(MMR)proteins(MLH1andMSH2).WeanalyzedKRASandBRAFgenemutations,andthemicrosatelliteinstability(MSI)status.TheimmunohistochemicalstainingofCD10,MUC2,MUC5ACandMUC6wasconsideredpositivewhendistinctstainingin>5%oftheadenocarcinomacellswasrecorded.ToevaluateofMMRproteinexpression,weusedadjacentnormaltissueincludinglymphoidfollicles,inflammatorycells,andstromalcellsasaninternalpositivecontrol.SectionswithoutnuclearstaininginthetumorcellswereconsideredtohavelosttheexpressionoftherespectiveMMRprotein.RESULTS:Therewere29malesand18femalespatients(meanage59.9years,range:23-87years).Tumorswerelocatedintheduodenumin14cases(30%),thejejunumin21cases(45%),andtheileumin12cases(25%).Aphenotypicexpressionanalysisrevealed20MUC2-positivetumors(42.6%),11MUC5AC-positive(23.4%),4MUC6-positive(8.5%),and7CD10-positive(14.9%).ThetumorsizesoftheMUC2(+)tumorsweresignificantlylargerthanthoseoftheMUC2(-)tumors(mean,5.7±1.4cmvs4.7±2.1cm,P<0.05).AllthreetumorswithadenomatouscomponentwerepositiveforMUC2(P<0.05).PolypoidappearancewasseensignificantlymorefrequentlyintheCD10(+)groupthanintheCD10(-)group(P<0.05).ThetumorsizewassignificantlylargerintheCD10(+)groupthanintheCD10(-)group(mean,5.9±1.4cmvs5.0±2.1cm,P<0.05).Of34SIAswithsuccessfullyobtainedMSIdata,4wereMSI-high.O

  • 标签: Small INTESTINE ADENOCARCINOMA MUCIN CD10 Microsat
  • 简介:Generationofzonalflowsbysmall-scaledrift-Alfvenmodesisinvestigatedbyadoptingtheapproachofparametricinstabilitywiththeelectronpolarizationdriftincluded.Thezonalmodecanbeexcitedbyprimarymodespropagatingatbothelectronandiondiamagneticdriftdirectionsincontrasttotheassertioninpreviousstudiesthatonlyprimarymodespropagatingintheiondiamagneticdriftdirectionscandrivezonalinstabilities.Generally,thegrowthrateofthedrivenzonalmodeisinthesameorderasthatinpreviousstudy.However,differentfromthepreviouswork,thegrowthrateisnolongerproportionaltothedifferencebetweenthediamagneticdriftfrequenciesofelectronsandions.

  • 标签: 小规模 漂移 带状流 电子极化 分区模式 驱动模式
  • 简介:Thispaperproposesaconstitutivelawandamethodforcharacterizinghighlypreloadedviscoelasticmaterialssubjectedtolinear(small-amplitude)vibrations.Amultiplicativenon-separablevariableslawhasbeensuggestedtomodelthebehaviorthatdependsonbothstretchandtime/frequency.Thisapproachallowssplittingtheintricatecombinedtestperformedsimultaneouslyonbothstretchandfrequency,generallyinalimitedexperimentaldomainupto100Hz,intotwoindependenttests.Thus,ononehand,thedynamiccomplexmodulusdependentonfrequencyaloneisevaluatedonthebasisofvibrationtestsinalargeexperimentaldomainupto100kHz.Ontheotherhand,energeticparametersaredeterminedfromaquasi-statichyperelastictensiletest.Thecomplexmodulus,dependentonbothstretchandfrequency,isthendeducedfromtheresultsacquiredfromuncoupledinvestigations.Thisworkshowsthat,inextension,theelasticmodulusincreaseswithincreasingstretch,andthelossfactordecreaseswithincreasingstretch;while,incompression,aroundthematerialundeformedstate,themodulusincreasesasthestretchincreasestillacertainvalueofcompressionstretch(upturnpointdependingonmaterialcharacteristics),andthenthemodulusdecreasesasthestretchincreases.Globally,preloadrigidifiesmaterialsbutreducestheirdampingproperty.Theseresultscloselymatchawell-knownobservationinsolidmechanics.

  • 标签: 橡胶类材料 振动试验 拉伸试验 加载 幅度 弹性模量
  • 简介:Weproposeanovelsmall-anglemeasuringopticalmethodbasedontheastigmaticeffectoftwoorthogonallyplacedcylindricallenses.Accordingtotheone-to-onecorrespondencebetweenthelaserspotshapeandtheangle,theangleisdetermined.Wetheoreticallyanalyzethemeasuringrangeanddemonstratethatalongerdistancebetweentherotatingaxisandtheopticalaxisleadstoasmallermeasuringrange,butbettersensitivity.Also,anassociatedexperimentalsystemisestablishedandameasuringrangeof0.94mrad(cubicfitr=0.9993)aswellasagoodlinearrangeof0.37mrad(linearfitr=0.9994)witharesolutionof8μradisachieved.

  • 标签: 角位移测量 光学方法 像散 线性拟合 测量范围 小角度测量
  • 简介:二个小尺寸的包裹方法,基于的包裹方法和plating黄金基于的薄不锈钢试管为纤维布拉格包装方法栅栏(FBG)温度传感器,被设计。在环境温度between203K和243K的FBG温度传感器的特征被调查。温度的功能试验性地被检验的FBG温度传感器的波长。处于相同条件的二个不同small-sizepackage传感器的实验结果与对方相比。传感器的传播光谱在273K和213K的温度被分析。温度传感器的敏感因素是导出的经分解并且被实验验证。到thewavelength温度曲线的线性适合被执行。

  • 标签: 不锈钢管 BRAGG光栅 FBG 低温 温度传感器