简介：NumericalexperimentsofadjointvariationalassimilationhavebeenperformedusingtheknownLorenzsystem.Withtheincreaseofsensitivityofmodel’sinitialvalues,itismoreandmoredifficulttousetheadjointmethodtogettheinitialvalueswhichareconsistentwiththedynamicsofthefore-castmodel.Undersomecircumstancesthealgorithmcompletelyfails.Thisshowsthatfour-dimen-sionalassimilationisrelatedtothelimitofpredictability.Ontheotherhand.withtheincreaseofmodelequation’serror,theresultofvariationalassimilationmaybecomeworseandworsesothatthepredictionhasnomeaning.Butifthemodelparametersarecorrectedwhenvariationalassimilationismade,theforecastresultscanbegreatlyimprovedbasedonLorenzmodel.

简介：被动导致电影的压力和危险性在在各种各样的pH价值的3.5%钠氯化物答案的7050铝合金的SCC被慢紧张率测试调查(SSRT)并且流动应力微分方法。结果证明到SCC的被动导致电影的压力和危险性与增加pH减少了价值什么时候pH7，当他们与增加pH增加了时价值什么时候pH>7。然而，当，腐蚀类型被解释脱落腐蚀什么时候pH=1并且14，并且没有电影，在标本的表面上形成。整个变化与pH导致电影的应力和SCC危险性阴谋当，价值两个都被介绍山谷形状。导致电影的压力的标志和数量与被动电影的作文有关，它用X光检查光电子被分析光谱学(XPS)。

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简介：Inordertotesttheaccuracyoftheusually-usedfixedcalibrationfactorofthecanopyscannerofLAI-2000formeasuringtheleafareaindex(LAI),aLarixprincipis-rupprechtiiplantationwaschoseninthesmallwatershedofXiangshuihelocatedattheLiupanMountainsofNingxiaHuiAutonomousRegionofNWChina,theLAIwasmeasuredinOctober2010,aperiodfromfullcanopytothetotalfallofneedles,byusingboththeLAI-2000andlitterfallcollectionmethod.Then,acomparisonwasmadebetweentheLAIvaluesdeterminedbythelitter-fallcollectionandthatcalculatedbasedonthefiguresreadfromLAI-2000andthefixedcalibrationfactor(1.49).ItshowedthattheaverageofLAImeasurementsofthe2methodswasveryclose,withadifferenceofonly5%.However,thecalculatedLAIfromLAI-2000wasobviouslyhigherthanthetruevaluesdeterminedbylitter-fallcollectionwhenthecanopywasfullofneedles;andobviouslylowerthanthetruevaluewhenthecanopywassparseafterneedlefalling.ThereasonmaybethatLAI-2000takestheprojectionoftwigsasneedles.So,adynamiccalibrationfactorisneeded,especiallyintheseasonswhentheneedleamountandthepercentageoftwigsprojectionincrownprojectionchangequickly.Therefore,astatisticrelationinaquadraticpolynomialformbetweenthe2seriesofLAIdatawaswellfitted.ThisrelationcanbeusedforamoreaccurateestimationofLAIbasedonthedatareadfromtheeasilyusedcanopyscannerslikeLAI-2000.

简介：Themicroscopiceffectivechargesinmirrornuclei51Mnand51Feareinvestigatedwiththeparticle-vibrationcouplingmodelbasedontheself-consistentSkyrme-Hartree-Fockandcontinuumrandom-phase-approximationapproaches.Theisovectorpartsarepredictedtobearound0.15,andtheprotoneffectivechargesarearound1.25e,whichislessthantheempiricalvalueofeeffp=1.5e.Themicroscopiceffectivechargesinneutronrich51Mnareabout10%lessthanitsprotonrichmirror.TheseeffectivechargesarecombinedwiththeshellmodeltocalculatethereducedelectricquadrupoletransitionprobabilityB(E2)valuesin51Mnand51Fe.ItturnsoutthatthemicroscopiceffectivechargeshavewellreproducedtheB(E2)valuesanditsratiointheterminatingstates.

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简介：AbstractBackground:Drug-coated balloons (DCBs) have emerged as potential alternatives to drug-eluting stents in specific lesion subsets for de novo coronary lesions. Quantitative flow ratio (QFR) is a method based on the three-dimensional quantitative coronary angiography and contrast flow velocity during coronary angiography (CAG), obviating the need for an invasive fractional flow reserve procedural. This study aimed to assess the serial angiographic changes of de novo lesions post-DCB therapy and further explore the cut-off values of lesion and vessel QFR, which predict vessel restenosis (diameter stenosis [DS] ≥50%) at mid-term follow-up.Methods:The data of patients who underwent DCB therapy between January 2014 and December 2019 from the multicenter hospital were retrospectively collected for QFR analysis. From their QFR performances, which were analyzed by CAG images at follow-up, we divided them into two groups: group A, showing target vessel DS ≥50%, and group B, showing target vessel DS <50%. The median follow-up time was 287 days in group A and 227 days in group B. We compared the clinical characteristics, parameters during DCB therapy, and QFR performances, which were analyzed by CAG images between the two groups, in need to explore the cut-off value of lesion/vessel QFR which can predict vessel restenosis. Student’s t test was used for the comparison of normally distributed continuous data, Mann-Whitney U test for the comparison of non-normally distributed continuous data, and receiver operating characteristic (ROC) curves for the evaluation of QFR performance which can predict vessel restenosis (DS ≥50%) at mid-term follow-up using the area under the curve (AUC).Results:A total of 112 patients with 112 target vessels were enrolled in this study. Group A had 41 patients, while group B had 71. Vessel QFR and lesion QFR were lower in group A than in group B post-DCB therapy, and the cut-off values of lesion QFR and vessel QFR in the ROC analysis to predict target vessel DS ≥50% post-DCB therapy were 0.905 (AUC, 0.741 [95% confidence interval, CI: 0.645, 0.837]; sensitivity, 0.817; specificity, 0.561; P < 0.001) and 0.890 (AUC, 0.796 [95% CI: 0.709, 0.882]; sensitivity, 0.746; specificity, 0.780; P < 0.001).Conclusions:The cut-off values of lesion QFR and vessel QFR can assist in predicting the angiographic changes post-DCB therapy. When lesion/vessel QFR values are <0.905/0.890 post-DCB therapy, a higher risk of vessel restenosis is potentially predicted at follow-up.