简介：AbstractBackground:Various experimental and clinical studies have reported on coronary microcirculatory dysfunction ( "no-reflow" phenomenon). Nevertheless, pathogenesis and effective treatment are yet to be fully elucidated. This study aimed to measure the intracoronary pressure gradient in the no-reflow artery during emergent percutaneous coronary intervention and explore the potential mechanism of no-reflow.Methods:From September 1st, 2018 to June 30th, 2019, intracoronary pressure in acute myocardial infarction patient was continuously measured by aspiration catheter from distal to proximal segment in the Department of Coronary Care Unit, Tianjin Chest Hospital, respectively in no-reflow arteries (no-reflow group) and arteries with thrombolysis in myocardial infarction-3 flow (control group). At least 12 cardiac cycles were consecutively recorded when the catheter was pulled back. The forward systolic pressure gradient was calculated as proximal systolic pressure minus distal systolic pressure. Comparison between groups was made using the Student t test, Mann-Whitney U-test or Chi-square test, as appropriate.Results:Intracoronary pressure in 33 no-reflow group and 26 in control group were measured. The intracoronary forward systolic pressure gradient was －1.3 (－4.8, 0.7) and 3.8 (0.8, 8.8) mmHg in no-reflow group and control group (Z = －3.989, P < 0.001), respectively, while the forward diastolic pressure gradient was －1.0 (－3.2, 0) and 4.6 (0, 16.5) mmHg in respective groups (Z = －3.851, P < 0.001). Moreover, the intracoronary forward pressure gradient showed significant difference between that before and after nicorandil medication (Z=－3.668, P < 0.001 in systolic pressure gradient and Z =－3.530, P < 0.001 in diastolic pressure gradient).Conclusions:No reflow during emergent coronary revascularization is significantly associated with local hemodynamic abnormalities in the coronary arteries. Intracoronary nicorandil administration at the distal segment of a coronary artery with an aspiration catheter could improve the microcirculatory dysfunction and resume normal coronary pressure gradient.Clinical trial registration:www.ClinicalTrials.gov (No. NCT 03600259).

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简介：Thepressuregradientofthelithosphereisakeytoexplainingvariousgeologicalprocesses,andvariesalsointimeandspacesimilartothegeothermalgradient.Inthispaperacorrelationformulaofgeothermalgradientsandpressuregradientswasbuiltwiththethermocomprestioncoefficients.Basedonthisformula,thearticlehasstudiedtherelationbetweenthepressuregradientsandthegeothermalgradientsinthelithosphere,andtheresultsindicatethatthepressuregradientinthelithosphereisnonlinear,anditsminimumvalueisthelithostaticgradient,andthatthepressuregradientofthelithospherewillincreaseobviouslywiththecontributionofbothgeothermalandgravity,andcouldbetwicetimesmorethanthelithostaticgradient.

简介：Thetechniqueoncomputingthehorizontalpressuregradientforce(PGF)inRegCM2isimprovedwiththeerrorsubtractionmethod.Moreover,theregionalclimateinJuneof1991inChinaissimulatedbyemployingtheRegCM2.ComparisonwithotherschemesforcomputingthePGFshowsthattheerrorsubtractionmethodcaneffectivelyreducetheerrorofthePGF,improvethesimulationofwindsandalleviatethespuriousprecipitationinsteeptopographicareas.Furthermore,thesimulationofprecipitationinotherareasisinbetteraccordancewiththeobservation.

简介：AIM:Todeterminethecorrelationbetweenthehepaticvenouspressuregradientandtheendoscopicgradeofesophagealvarices.METHODS:FromSeptember2009toMarch2013,atotalof176measurementsofhepaticvenouspressuregradient(HVPG)weredonein146patients.EachtransjugularHVPGwasmeasuredtwice,firstusinganendwholecatheter(EH-HVPG),andthenusingaballooncatheter(B-HVPG).TheHVPGwascomparedwiththeendoscopicgradeofesophagealvarices(accordingtothegeneralrulesforrecordingendoscopicfindingsofesophagogastricvarices),whichwasrecordedwithinamonthofthemeasurementofHVPG.RESULTS:Thestudyincluded110menand36women,withameanageof56.1years(range,43-76years).Thetechnicalsuccessrateofthepressuremeasurementswas100%andtherewerenocomplicationrelatedtotheprocedures.MeanHVPGwas15.3mmHgasmeasuredusingtheendholecathetermethodand16.5mmHgasmeasuredusingtheballooncathetermethod.MeanHVPG(bothEHHVPGandB-HVPG)wasnotsignificantlydifferentamongpatientswithdifferentcharacteristics,includingsexandcomorbidfactors,exceptforcaseswithhepatocellularcarcinoma(B-HVPG,P=0.01;EH-HVPG,P=0.02).Portalhypertension(>12mmHgHVPG)occurredin66%ofpatientsaccordingtoEH-HVPGand83%ofpatientsaccordingtoB-HVGP,andsignificantlycorrelatedwithChild’sstatus(B-HVPG,P<0.000;EHHVGP,P<0.000)andesophagealvariesobserveduponendoscopy(EH-HVGP,P=0.003;B-HVGP,P=0.006).Onehundredandthirty-fiveendoscopieswereperformed,ofwhich15showednormalfindings,27showedgrade1endoscopicesophagealvarices,49showedgrade2varices,and44showedgrade3varices.WhencomparingendoscopicesophagealvaricealgradesandHVPGusingunivariateanalysis,thePvaluewas0.004forEH-HVPGand0.002forB-HVPG.CONCLUSION:BothEH-HVPGandB-HVPGshowedapositivecorrelationwiththeendoscopicgradeofesophagealvarices,withB-HVPGshowingastrongercorrelationthanEH-HVPG.

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简介：Itiswidelyacceptedthatinaturbulentboundarylayer(TBL)withadversepressuregradient(APG)anouterpeakusuallyappearsintheprofileofstreamwiseReynoldsstress.However,theeffectofAPGonthisouterpeakisnotclearlyunderstood.Inthispaper,theeffectofAPGisanalysedusingthenumericalandexperimentalresultsintheliterature.BecausetheeffectofupstreamflowisinherentintheTBL,wefirstanalysethiseffectinTBLswithzeropressuregradientonflatplates.Undertheindividualeffectofupstreamflow,anouterpeakalreadyappearsintheprofileofstreamwiseReynoldsstresswhentheTBLcontinuesdevelopinginthestreamwisedirection.TheAPGacceleratestheappearanceoftheouterpeak,insteadofbeingatrigger.

简介：试验性的研究长证明了在在热力学的状态不是的supercritical的液体的围住墙的狂暴的流动的力量对流的热转移精确地由关联预言在subcritical为单相的液体被开发了热力学的状态。在现在的计算学习，狂暴的流动的统计性质以及在zero-pressure-gradient平板边界层的协调流动结构的开发当身体力量不在时被调查，在工作液体在supercritical是热力学的状态的地方。模仿的边界层为二热流动被开发到250的一个磨擦雷纳兹数字到相应于正常的热转移和改进的热转移被观察的案例的集体流动的比率。在改进的热转移被观察的地方，在情况中，近墙的协调流动结构的spanwise间距被减少由于一相对不太稳定的流动环境源于墙正常粘性坡度侧面的更低的大小。

简介：Densitystratifiedflowwithboththeverticaltemperaturegradientandtheverti-calsalinitygradientissimulatednumerically,inwhichturbulenttermsarecalculatedbyasim-plifiedturbulencestress/fluxalgebraicmodel.Thefeatureofstratificationandturbulenceisde-scribedcorrectlybythemodel.Thecomputationalresultsagreewellwiththeexperimentaldata.However,thek-eturbulencemodelisnotsosuccessful.

简介：作者学习Helfrich的L2坡度流动功能，它是功能的描述人的红血房间的形状。为任何i0并且c0，作者在光滑的答案的lifespan上获得更低的界限，它为起始的表面仅仅取决于弯曲的集中。

简介：Standingwavesareformedduetothereflectionwhenwavesmeetverticalwall,thereforestrongstructuresareneededtokeepthewallstabilityundertheseriouswaveattack.Fortheimprovementoftheworkingconditionandincreaseofthestabilityofthewall,thelowerreflectingbreakwatershaveat-tractedcloseattentionReportsmostlyfromJapaneseresearchersareoftenconcernedwiththewallofcaissonequippedwithopenwindows.Inthispaperakindofhollow-pipeperforatedbreakwaterisexam-inedwhichwavesmaypartiallyperforateintotheharbourbasin.Thewaveinfrontofthewallcanonlyformpartialstandingwaveandwaveforceisreducedobviously.Andthetheoreticalcalculationofwaveforceandanalysisofwaveforcespectrumareallderived.Comparisonbetweentheresultsfromtheoreticalcalculationandhydraulicmodelingshowsreasonableagreement.

简介：为紧张坡度的一个无限的平板，敏感材料使遭到了到飞机紧张张力的装载，建立的计算和分析证实在装载的一些舞台的侧面的边界的那钝化在进一步的装载之上禁止塑料变丑。除了显著地，如果坡度术语贡献驱散，塑料变丑完全被关上并且仅仅在清楚地定义的更高的负担恢复之外，这结果在自己是不令人吃惊的，相应于全部的紧张\(\varepsilon_c\)，说。在这份报纸介绍的分析证实塑料变丑追随者钝化的延期并且决定塑料流动在恢复的准确方式。塑料紧张率在塑料流动的恢复的准确的点\(\varepsilon_c\)是连续的并且为在强加的全部的紧张的第一小增长\(\Delta\varepsilon=\varepsilon-\varepsilon_c\)，在塑料的相应增长紧张，\(\Delta\varepsilon^\mathrm{p}\)，与\成正比((\Delta\varepsilon)^2\)。在关系\的经常的A(\Delta\varepsilon^\mathrm{p}(0)=A(\Delta\varepsilon)^2\)，在此\(\Delta\varepsilon^\mathrm{p}(0)\)在平板的中心表示塑料紧张增长，明确地被决定了；它取决于材料的变硬的模量。除非消散的术语是不在的，精力充沛的坡度术语的存在没在\(\varepsilon_c\)的价值上有效果，在哪个情况钝化减少塑料变丑的率，但是不介绍延期。消散的坡度术语的这质的效果打开他们的存在或缺席的试验性的辨别的可能性。分析采用是可能的处于另外的问题发现使用的增长变化明确的表达。

简介：Thissurveyreviewstherecentdevelopmentofgradientdomainmeshdeformationmethod.Differenttootherdeformationmethods,thegradientdomaindeformationmethodisasurface-based,variationaloptimizationmethod.Itdirectlyencodesthegeometricdetailsindifferentialcoordinates,whicharealsocalledLaplaciancoordinatesinliterature.BypreservingtheLaplaciancoordinates,themeshdetailscanbewellpreservedduringdeformation.DuetothelocalityoftheLaplaciancoordinates,thevariationaloptimizationproblemcanbecastedintoasparselinearsystem.Fastsparselinearsolvercanbeadoptedtogeneratedeformationresultinteractively,oreveninreal-time.Thenonlinearnatureofgradientdomainmeshdeformationleadstothedevelopmentoftwocategoriesofdeformationmethods:linearizationmethodsandnonlinearoptimizationmethods.Basically,thelinearizationmethodsonlyneedtosolvethelinearleast-squaressystemonce.Theyarefast,easytounderstandandcontrol,whilethedeformationresultmightbesuboptimal.Nonlinearoptimizationmethodscanreachoptimalsolutionofdeformationenergyfunctionbyiterativeupdating.Sincethecomputationofnonlinearmethodsisexpensive,reduceddeformablemodelsshouldbeadoptedtoachieveinteractiveperformance.Thenonlinearoptimizationmethodsavoidtheuserburdentoinputtransformationatdeformationhandles,andtheycanbeextendedtoincorporatevariousnonlinearconstraints,likevolumeconstraint,skeletonconstraint,andsoon.Wereviewrepresentativemethodsandrelatedapproachesofeachcategorycomparativelyandhopetohelptheuserunderstandthemotivationbehindthealgorithms.Finally,wediscusstherelationbetweenphysicalsimulationandgradientdomainmeshdeformationtorevealwhyitcanachievephysicallyplausibledeformationresult.

简介：为非强迫的优化在方法上介绍研究。学习的假设；主要结果；在简化Armijo类型下面的方法的集中性质衬里搜索。

简介：Theconjugategradientmethodforunconstrainedoptimizationproblemsvarieswithascalar.Inthisnote,ageneralconditionconcerningthescalarisgiven,whichensurestheglobalconvergenceofthemethodinthecaseofstrongWolfelinesearches.ItisalsodiscussedhowtousetheresulttoobtaintheconvergenceofthefamousFletcher-Reeves,andPolak-Ribiere-Polyakconjugategradientmethods.Thattheconditioncannotberelaxedinsomesenseismentioned.

简介：Themainpurposeofthispaperistoprovidearestartingdirectionforimprovingonthestandardconjugategradientmethod.Ifadrasticnon-quadraticbehaviouroftheobjectivefunctionisobservedintheneighbourofxk,thenarestartshouldbedone.Thescalingsymmetricrank-oneupdatewithDavidon’soptimalcriterionisappliedtogeneratetherestartingdirection.Itisprovedthattheconjugategradientmethodwiththisstrategyretainsthequadratictermination.Numericalexperimentsshowthatitissuccessful.

简介：基于精力的一个新种类坡度理论非局部的模型在这篇论文被建议，并且理论被使用在薄金属性的电线扭转调查尺寸效果，极端薄的横梁弯曲并且多晶的铜微缩进。首先，一个精力非局部的模型被建议。基于模型，第二，一个新种类坡度理论被导出。第三，新理论被使用分析三个代表性的实验。

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简介：AstudentsuicidelastWednesdayinGuangzhouhasnotonlymadethevictim'sfamilysadbuthasshowntheseriousnessofdepressionandmentalfragilityamongstudents.