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  • 简介:AbstractFor the detection of steatosis, quantitative ultrasound imaging techniques have achieved great progress in past years. Magnetic resonance imaging proton density fat fraction is currently the most accurate test to detect hepatic steatosis. Some blood biomarkers correlate with non-alcoholic steatohepatitis, but the accuracy is modest. Regarding liver fibrosis, liver stiffness measurement by transient elastography (TE) has high accuracy and is widely used across the world. Magnetic resonance elastography is marginally better than TE but is limited by its cost and availability. Several blood biomarkers of fibrosis have been used in clinical trials and hold promise for selecting patients for treatment and monitoring treatment response. This article reviews new developments in the non-invasive assessment of non-alcoholic fatty liver disease (NAFLD). Accumulating evidence suggests that various non-invasive tests can be used to diagnose NAFLD, assess its severity, and predict the prognosis. Further studies are needed to determine the role of the tests as monitoring tools. We cannot overemphasize the importance of context in selecting appropriate tests.

  • 标签: Fatty liver Non-alcoholic fatty liver disease Non-alcoholic steatohepatitis Liver fibrosis Cirrhosis Transient elastography FibroScan Magnetic resonance imaging
  • 简介:Thispaperinvestigatesthemathematicfeaturesofnon-linearmodelsanddiscussestheprocessingwayofnon-linearfactorswhichcontributestothenon-linearityofanonlinearmodel.Onthebasisoftheerrordefinition,thispaperputsforwardanewadjustmentcriterion,SGPE.Last,thispaperinvestigatesthesolutionofanon-linearregressionmodelinthenon-linearmodelspaceandmakesthecomparisonbetweentheestimatedvaluesinnon-linearmodelspaceandthoseinlinearmodelspace.

  • 标签: 非线性调节模型 测量误差 精确度 空间非线性模型
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  • 简介:Anumericalanalysisofnon-Newtonianfluidflowinnon-planararterywithbifurcationwasperformedbyusingafiniteelementmethodtosolvethethree-dimensionalNavier-Stokesequationscoupledwiththenon-Newtonianconstitutivemodels,includingCarreau,CrossandBinghammodels.Theobjectiveofthisstudyistoinvestigatetheeffectsofthenon-Newtonianpropertiesofbloodaswellascurvatureandout-of-planegeometryinthenon-planardaughtervesselsonthevelocitydistributionandwallshearstress.Theresultsofthisstudysupporttheviewthatthenon-planarityofbloodvesselsandthenon-Newtonianpropertiesofbloodareofimportantinhemodynamicsandplayasignificantroleinvascularbiologyandpathophysiology.

  • 标签: 非线性牛顿流体 血液动力学 颈动脉分流 数值分析 非平面动脉 病理生理学
  • 简介:Bacterialflagellarfilamentcanundergoastress-inducedpolymorphicphasetransitioninbothvitroandvivoenvironments.Thefilamenthas12differenthelicalforms(phases)characterizedbydifferentpitchlengthsandhelixradii.Whensubjectedtothefrictionalforceofflowingfluid,thefilamentchangesbetweenaleft-handednormalphaseandaright-handedsemi-coiledphaseviaphasenucleationandgrowth.Thispaperdevelopsnon-localfiniteelementmethod(FEM)tosimulatethephasetransitionunderad...

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  • 简介:SeveralextensionsofthelogicprogramminglanguagePrologtononHornclausesusecaseanalysistohandlenon-Hornclauses.Inthispaper,analyticalandempriricalevidencesarepresentedtoshowthat,bymakingasetofclausesless'non-Horn'usingpredicatedrenaming.theperformanceofthesecase-analysisbasedprocedurescanbeimprovedsignificantly.Inaddition,thepaperalsoinvestigatedtheproblemofefficeientlyconstructingapredicaterenamingthatreducesthedegreeof'non-Hornness'ofaclausesetmaximally.Itisshownthatthisproblemoffindingaredicaterenamingtoachieveminimal'non-Hornness'isNP-complete.

  • 标签: 人工智能 逻辑程序设计 NP-完备性
  • 简介:Akineticequationofnon-isothermalcrystamzationwasderivedbyextendingAvrami’sequationtothenon-isothermalsituation.Morecrystallizationinformationcanbeobtainedfromthiskineticequation.Thecurvesofnon-isothermalandisothermalcrystallizationswereanalysedandcomparedforpoly(ethyleneterephthalate)(PET),andtheresultswerediscussed.

  • 标签: NON-ISOTHERMAL CRYSTALLIZATION CRYSTALLIZATION KINETICS Poly (ethyene
  • 简介:Non-invasiveventilation(NIV)istheprovisionofventilatorysupportwithoutinstrumentationoftheairway.Itcanbeachievedusinganegative-pressuremachine(e.g.‘ironlung')or,morecommonly,withpositivepressureadministeredthroughawell-fittingmask.Thiscontributionconsiderspositivepressureventilationonly;negativepressureisnowseldomused.

  • 标签: 非入侵型机械通气 NIV 通气支持 持续正压通气 呼吸衰竭
  • 简介:为光滑的功能的一个家庭,作者显示出那,在某些通用条件下面,所有extremal(最小、最大)点是非退化的。

  • 标签: 非退化 极值点 光滑函数
  • 简介:在这篇论文,非各向同性的Jacobi假光谱方法被建议,它的应用斧子考虑了。一些结果在上;多维的Jacobi高斯类型插值和相关Bernstein杰克森类型不平等斧子建立了,它起一个重要作用在假光谱方法。假光谱方法被用于一二--维的单个问题中间axisymmetric上的一个问题领域。建议计划的集中被建立。数字结果表明建议方法的效率。

  • 标签: 多倍面积 不等式 奇数问题 计算数学
  • 简介:Abriefaccountisprovidedoncrack-tipsolutionsthathaverecentlybeenpublishedintheliteraturebyemployingtheso-calledGRADELAmodelanditsvariants.TheGRADELAmodelisasimplegradientelasticitytheoryinvolvingoneinternallengthinadditiontothetwoLame'constants,inanefforttoeliminateelasticsingularitiesanddiscontinuitiesandtointerpretelasticsizeeffects.Thenon-singularstrainsandnon-singular(butsometimessingularorevenhypersingular)stressesderivedthiswayunderdifferentboundaryconditionsdifferfromeachotherandtheirphysicalmeaninginnotclear.Thisisdiscussedwhichfocusontheformandphysicalmeaningofnon-singularsolutionsforcrack-tipstressesandstrainsthatarepossibletoobtainwithintheGRADELAmodelanditsextensions.

  • 标签: 非奇异解 裂纹尖端 弹性理论 物理意义 拉梅常数 内部长度
  • 简介:Data ,27.3%,from 

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  • 简介:作者为可能非加倍,但是满足某些生长条件的氡措施给Morrey空格的一个自然定义,并且在泛音分析和他们的珍视向量的扩展在一些古典操作符的这些空格调查围住的海角。

  • 标签: MORREY空间 双重测量 向量值 清晰度 有界性
  • 简介:与IGS的每日的SINEX文件,IGS车站的时间序列与并列模式在概括网络调整模型下面用一个独立地发达的软件被获得。从时间序列,非线性的运动被发现。与光谱分析方法,地点速度的变化频率(年度时期和一年两次的时期)被发现。而且,车站的速度变化的实验模型被回归分析方法基于车站的每周的答案坐标系列建立了。关于追踪车站的IGS的速度,周期性地为变化建模或用片明智的线性功能而非一个线性变量周期性地给速度估计它的偏爱更好。

  • 标签: IGS测站 非线性变化 光谱分析 经验模型
  • 简介:把早期的运动基于不一致的沉积的机制,拖强迫并且高举力量系数表情为不一致的床材料暴露和靠近的排列状态被提出。不一致的沉积的早期的速度公式然后被建立。公式结构合理、好,这被显示出不一致的沉积的粒子比一样缩放一致粒子的是更困难的设定进运动,而更粗糙的粒子更容易比他们的一致等价物设定进运动。公式的有效性由地和实验数据被验证。

  • 标签: 初始速度 沉淀物 物质分配 河道处理