学科分类
/ 5
92 个结果
  • 简介:AnewmechanicsmodelbasedonPeierlsconceptispresentedinthispaper,whichcanclearlycharacterizetheintrinsicfeaturesnearatipofaninterfacialcrack.Thestressanddisplacementfieldsarecalculatedundergeneralcombinedten-sileandshearloadings.Theneartipstressfieldsshowsomeoscillatorybehaviorsbutwithoutanysingularityandthecrackfacesopencompletelywithoutanyoverlappingwhenremotetensileloadingiscomparablewithremoteshearloading.Afracturecriterionforpredictinginterfacetoughnesshasbeenalsoproposed,whichtakesintoaccountfortheshieldingeffectsofemitteddislocations.Thetheoreticaltoughnesscurvegivesexcellentprediction,ascomparedwiththeexistingexperimentdata.

  • 标签: MICROMECHANICS INTERFACE CRACK TOUGHNESS
  • 简介:Satanhimselfisthemysteriouspowerthatcontrolsthelivesofthehumanrace.HetoldTheodorFischerthathumanlifeisachaininwhichatinymovewillwhollychangedone’slifeandthat,Thefinger-sizemenandwomenmadebySataninChapter2remindedthereadersthesplendidbiblestoryofGodcreatingtheworldandhuman.ButSatan,TheDamnedHumanRace)butbecauseitshowstheflawsandwerealizethatitiswhatreallyhappensinreallifeandthatweourselvesareexactlywhatSatansaidtheonlyracewith

  • 标签:
  • 简介:

  • 标签:
  • 简介:the meals often have a great cementing effect on family life. In the eyes of the British people,half of the flavoring could not be found here. Maybe that is one of the reasons why the British food is not very delicious.The British people like desserts very much,and some have no breakfast at all or only a hot drink. The midday lunch time is from about 12

  • 标签:
  • 简介:Baiyuneboite-(Ce)isanewfluor-carbonatemineral.Basedonthefinedataonthestructureofthemineral,thefactorgroupandnormalcoordinateanalysesforitsinfraredspectrumhavebeencarriedout.ThefactorgroupanalysesindicatethatthesitegroupandfactorgroupsplittingsoftheinternalvibrationbandsofCO3^2-ionsdonotoccurandthatthedoublebandsofnormalmodesresultfromtwonon-equalsetsofCO3^2-ionsinthecrystalstructure,Thenormalcoordinateanalysesgivethestretchingforceconstants.bendforceconstantsandcalculatedfrequenciesofCO3^2-ions.Thecalculationsofpotentialenergydistributionallowustoassignv3andv4tothestretchingvibrationandthebendvibrationofCO3^2-ions.respectively.

  • 标签: 白云石 氟石 碳酸盐矿物 矿物结构 光谱
  • 简介:only a glass of wine will be a whole night. The wine culture in Britain is like the characteristics of the British people. So we seldom see some people drunkard in the street. Additionally if the food is different,British wine culture possesses the less sense of the sensitive considerations which is connected with the social superiorities and inferiorities. I think this is a distance between China and Britain. III. The significance of knowing the differences of customWe have had a glimpse of the different customs of Britain and China. Of course what we have discussed just now are only one small aspect of the different culture. To learn the different culture is very important for our English major students and it really means a lot. Then what is the significance of understanding these differences,the fish head would be left for the guest of honor - and it is the most nutritious part (the eyes and lips are the valued delicacies offered to the senior lady present). The platter holding the fish will always be laid on the table in such a way that the fish head points towards the guest of honor (at family meals

  • 标签:
  • 简介:weshouldunderstandthatthesuccessesoftheexchangesareonthebasisofmutualunderstandingofeachcountry’scustomandvalues.Thenwewillhavethepossibilitytomakeacademicexchangesandgainsomeachievements.Inauniversity,北京、上海,Inwhichwayisitwonderful

  • 标签:
  • 简介:Cellulasesareimportantglycosylhydrolases(GHs)thathydrolyzecellulosepolymersintosmalleroligosaccharidesbybreakingthecelluloseβ(1→4)bonds,andtheyarewidelyusedtoproducecellulosicethanolfromtheplantbiomass.N-linkedandO-linkedglycosylationswereproposedtoimpactthecatalyticefficiency,cellulosebindingaffinityandthestabilityofcellulasesbasedonobservationsofindividualcellulases.Asfarasweknow,therehasnotbeenanysystematicanalysisofthedistributionsofN-linkedandO-linkedglycosylatedresiduesincellulases,mainlyduetothelimitedannotationsoftherelevantfunctionaldomainsandtheglycosylatedresidues.Wehavecomputationallyannotatedthefunctionaldomainsandglycosylatedresiduesincellulases,andconductedasystematicanalysisofthedistributionsoftheN-linkedandO-linkedglycosylatedresiduesintheseenzymes.ManyN-linkedglycosylatedresidueswereknowntobeintheGHdomainsofcellulases,buttheyarethereprobablyjustbychance,sincetheGHdomainusuallyoccupiesmorethanhalfofthesequencelengthofacellulase.OuranalysisindicatesthattheO-linkedglycosylatedresiduesaresignificantlyenrichedinthelinkerregionsbetweenthecarbohydratebindingmodule(CBM)domainsandGHdomainsofcellulases.Possiblemechanismsarediscussed.

  • 标签: 纤维素酶 糖基化 生长激素 分布系统 连接器 碳水化合物
  • 简介:Thispaperanalysesamathematicalmodelofthepatternformationontheshellofmolluscswhichisactuallyakindofreaction-diffusionsystem.TheexistenceanduniquenessofaglobalsmoothsolutionofthissystemwithCauchyproblemanditsstabilityandtimedecayratearestudiedbymeansofanelementaryenergymethod.

  • 标签: 数学模型 软体动物 反应扩散方程 全局光滑解
  • 简介:Abundanttestdataarerequiredinassessmentofweaponperformance.Whenweapontestdataareinsufficient,Bayesiananalysesinsmallsamplecircumstanceshouldbeconsideredandthetestdatashouldbeprovidedbysimulations.TheseveralBayesianapproachesarediscussedandsomelimitationsarefounded.AnimprovementisputforwardafterlimitationsofBayesianapproachesavailableareanalyzedandtheimprovedapproachisappliedtoassessmentofsomenewweaponperformance.

  • 标签: 贝叶斯估计 小样本理论 武器 置信度
  • 简介:Lawofthepropagationoferrorscausedbytheinconsistencyoftheboundaryscalesimilitudeinrivermodelexperimentispresentedinthispaper.Thefluctuationofscaletransfersalongthecharacteristicline,ifthedischargeandsedimentatentranceandthewaterlevelatthetailgatedrift.Thefluctuationofscalepropagateswiththederivedscalefunctionduetotopographicdeviation.Allerrorswillaccumulatetothefinalmeasureddata

  • 标签: scale SIMILITUDE PROPAGATION of ERROR CONSISTENCY
  • 简介:AbstractBackground:High levels of plasma homocysteine occur almost uniformly in patients with end-stage renal disease (ESRD). IgA nephropathy (IgAN) is the most common form of primary glomerulonephritis and a common cause of ESRD in young adults. Here, we aimed to detect whether homocysteine was elevated and associated with clinical-pathologic manifestations of IgAN patients and tested its causal effects using a two-sample Mendelian randomization (MR) approach.Methods:For observational analysis, 108 IgAN patients, 30 lupus nephritis (LN) patients, 50 minimal change disease (MCD) patients, and 206 healthy controls were recruited from April 2014 to April 2015. Their plasma homocysteine was measured and clinical-pathologic manifestations were collected from medical records. For MR analysis, we further included 1686 IgAN patients. The missense variant methylenetetrahydrofolate reductase C677T (rs1801133) was selected as an instrument, which was genotyped by TaqMan allele discrimination assays.Results:Majority of IgAN patients (93.52%, 101/108) showed elevated levels of plasma homocysteine (>10 μmol/L). Plasma homocysteine in IgAN patients was significantly higher than that in MCD patients (median: 18.32 vs. 11.15 μmol/L, Z = -5.29, P < 0.01) and in healthy controls (median: 18.32 vs. 10.00 μmol/L, Z = -8.76, P < 0.01), but comparable with those in LN patients (median: 18.32 L vs. 14.50 μmol/L, Z = -1.32, P = 0.19). Significant differences were observed in sub-groups of IgAN patients according to quartiles of plasma homocysteine for male ratio (22.22% vs. 51.85% vs. 70.37% vs. 70.37%, χ2 = 14.29, P < 0.01), serum creatinine (median: 77.00 vs. 100.00 vs. 129.00 vs. 150.00 μmol/L, χ2 = 34.06, P < 0.01), estimated glomerular filtration rate (median: 100.52 vs. 74.23 vs. 52.68 vs. 42.67 mL·min-1·1.73 m-2, χ2 = 21.75, P < 0.01), systolic blood pressure (median: 120.00 vs. 120.00 vs. 125.00 vs. 130.00 mmHg, χ2 = 2.97, P = 0.05), diastolic blood pressure (median 80.00 vs. 75.00 vs. 80.00 vs. 81.00 mmHg, χ2 = 11.47, P < 0.01), and pathologic tubular atrophy and interstitial fibrosis (T) (T0/T1/T2: 62.96%/33.33%/3.70% vs. 29.63%/40.74%/29.63% vs. 24.00%/48.00%/28.00% vs. 14.81%/37.04%/48.15%, χ2 = 17.66, P < 0.01). The coefficient of each rs1801133-T allele on homocysteine levels after controlling age and sex was 7.12 (P < 0.01). MR estimates showed causal positive effects of homocysteine on serum creatine (β = 0.76, P = 0.02), systolic blood pressure (β = 0.26, P = 0.02), diastolic blood pressure (β = 0.20, P = 0.01), and pathologic T lesion (β = 0.01, P = 0.01) in IgAN.Conclusions:By observational and MR analyses, consistent results were observed for associations of plasma homocysteine with serum creatinine, blood pressures, and pathologic T lesion in IgAN patients.

  • 标签: Homocysteine IgA nephropathy Causality
  • 简介:Circulatingtumorcells(CTCs)areapopulationoftumorcellsmediatingmetastasis,whichresultsinmostofthecancerrelateddeaths.ThenumberofCTCsintheperipheralbloodofpatientsisrare,andmanyplatformshavebeenlaunchedfordetectionandenrichmentofCTCs.EnumerationofCTCshasalreadybeenusedasaprognosismarkerpredictingthesurvivalrateofcancerpatients.YetCTCsshouldbemorepotential.StudiesonCTCsatsinglecelllevelmayhelprevealingtheunderlyingmechanismoftumorigenesisandmetastasis.Thoughfarfromdeveloped,thisareaofstudyholdsmuchpromiseinprovidingnewclinicalapplicationanddeepunderstandingtowardsmetastasisandcancerdevelopment.

  • 标签: 肿瘤细胞 单细胞分析 循环 癌症患者 CTCS 肿瘤发生
  • 简介:Compositediaphragminflation(CDI)experimentisausefulmethodologyforexploringthemechanicsrelationofcell-celljunctionswithinalivingepithelialsheet.Inthispaper,anewmethodologyofCDIexperimenthasbeenputforward.Thefinitedeformationofacircularpolydimezhylsiloxaneelastomericmembrane,whichisusedasthesubstrateforthecultureofepithelialcells,underhydrostaticpressureisexploredbythetheoryofnon-linearcontinuummechanics.Thesimplifiedgoverningequationswithminimumamountofdifferentialequationsandboundaryconditionsareobtainedandsolvedbymultipleshootingmethod.Theinfluencesonthemembranebyhydrostaticpressurehavebeendiscussed.

  • 标签: 通货膨胀率 弹性膜片 静水压力 圆形 上皮细胞 力学关系