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  • 简介:ThedensitiesofCO_2inclusionsinmineralsarecommonlyusedtodeterminethecrystallizingconditionsofthehostminerals.However,conventionalmicrothermometryisdifficulttoapplyforinclusionsofsmallsize(<5-10μm)orlowdensity.RamananalysisisanalternativemethodfordeterminingCO_2density,providedthattheCO_2density-Ramanshiftrelationisknown.ThisstudyaimstoestablishthisCO_2density-RamanshiftrelationbyusingCO_2inclusionssynthesizedinfusedsilicacapillaries.Byusingthisnewly-developedsynthetictechnique,weformedpureCO_2inclusions,andtheirdensitiesweredeterminedbymicrothermometry.TheRamananalysisshowedthattherelationbetweenCO_2density(Ding/cm3)andtheseparations(△incm~(-1))betweenthetwomainbands(i.e.Fermidiadbands)inCO_2Ramanspectracanberepresentedbyacubicequation:D(g/cm~3)=0.74203(-0.019⊿~3+5.90332⊿~2-610.79472⊿+21050.30165)-3.54278(r~2=0.99920).OurcalculatedDvalueforagiven⊿isbetweenthoseobtainedfromtwopreviously-reportedequations,whichwerederivedfromdifferentexperimentalmethods.AnexamplewasgiveninthisstudytodemonstratethatthedensitiesofnaturalCO_2inclusionsthatcouldnotbederivedfrommicrothermometrycouldbedeterminedbyusingourmethod.

  • 标签: 矿物包裹体 二氧化碳 石英毛细管 拉曼分析 合成技术 碳密度
  • 简介:Weperformmicromagneticsimulationsontheswitchingofmagneticvortexcorebyusingspin-polarizedcurrentsthroughathree-nanocontactgeometry.Oursimulationresultsshowthatthecurrentcombinationwithanappropriatecurrentflowdirectiondestroysthesymmetryofthetotaleffectiveenergyofthesystemsothatthevortexcorecanbeeasiertoexcite,resultinginlesscriticalcurrentdensityandafasterswitchingprocess.Besidesitsfundamentalsignificance,ourfindingsprovideanadditionalroutetoincorporatingmagneticvortexphenomenaintodatastoragedevices.

  • 标签: 临界电流密度 极化电流 自旋极化 涡核 结构 密闭
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  • 简介:OptimalstockingdensitieswereinvestigatedfortheseacucumberApostichopusjaponicusSelenkaunderfeed-supplementandnon-feed-supplementregimesinnetenclosuresfor333d.Substantialweightlossoccurredduringtheaestivationphase(AE).Decreasedgrowthrateswerealsoobservedduringthewinterphase(WT).Incontrast,seacucumbersshowedrapidgrowthduringthespring(SP)andautumn(AU)phases.Feedingregimesconsiderablyinfluencedthegrowthperformance,i.e.,seacucumbersgrewfasterunderfeed-supplementregimethanundernon-feed-supplementregime(P<0.05).Theaveragesurvivalratesofseacucumbersunderfeed-supplementregimewerehigherthanthoseundernon-feed-supplementregimeforboththeautumnphaseandspringphase,butthedifferenceswereonlysignificantforthelatterphase(P<0.05).ThefittedB-Ncurvesshowedthattheoptimalstockingdensities,intermsofnetproduction,were22.3ind.m-2forfeed-supplementregimeand14.1ind.m-2fornon-feed-supplementregime.

  • 标签: 饲料补充 海参 养殖密度 池塘养殖 优化 编制
  • 简介:BackgroundIt'sestablishedthatLectin-likeoxidizedlow-densitylipoproteinreceptor-1(LOX-1)isinvolvedinintimalhyperplasiaafterballooninjury.Therecentevidencealsosuggeststhatvalsartanhasanantiatheroscleticeffect.Inthisstudy,theexpressionofLOX-1andtheeffectofvalsartanonitsexpressionwasinvestigatedinrataortaafterballooninjury.MethodsRatmodelofaorticendothelialdenudationwasinducedby2Fballooncatheter.Ratswererandomlydividedintothreegroups:control,operationandvalsartantreatment.Theaortictissuesweretakenfromratsineachgroupondays14and28aftersurgery.ThethicknessofvascularwallwasmeasuredwithHEstain,LOX-1mRNAandproteinweredeterminedbyreversetranscription-polymersechainreaction(RT-PCR)andimmunohistochemistry,respectively.ResultsComparedwiththecontrolgroup,significantintimalthickeningwasobservedatday14and28afterinjury.Comparedwiththeoperationgroup,intimalthicknessofeachtimepointwassignificantlydecreasedinvalsartantreatmentgroup.Atday14and28afterballooninjury,theexpressionlevelsofLOX-1mRNAandproteinweresignificantlyincreased,andweregreatlydecreasedaftervalsartantreatment.ConclusionsTheexpressionofLOX-1isincreasedafterendothelialinjury.Valsartaninhibitsaorticintimalthickeninginducedbyendothelialdenudation,whichisassociatedwiththedownregulationofLOX-1expression.

  • 标签: 低密度脂蛋白受体 球囊导管 主动脉 凝集素 损伤 大鼠
  • 简介:Hydrousrutheniumoxide(h-RuO2)nanoparticlesanditscompositewithmultiwalledcarbonnanotubes(h-RuO2/MWCNT)weresynthesizedbyasimplehydrothermalmethodandprovedtohavepotentialapplicationashybridsupercapacitormaterial.Theh-RuO2andh-RuO2/MWCNTwerecharacterizedfortheirphysico-chemicalpropertiesbyPXRD,BETsurfacearea,Raman,SEM-EDSandTEMtechniques.Theelectrochemicalperformanceofthematerialswereinvestigated,specificcapacitance(Cs)ofh-RuO2andhRuO2/MWCNTestimatedbytheircyclicvoltammetricstudieswerefoundtobe604and1585F/grespectivelyatascanrateof2mV/sinthepotentialrange0–1.2V.Further,thisvaluewasfoundtobenearlythreetimeshigherthanthatofpureh-RuO2.Anasymmetricsupercapacitor(AS)devicewasfabricatedbyemployingh-RuO2/MWCNTasthepositiveelectrodeandactivatedcarbonasthenegativeelectrode.ThedeviceexhibitedCsof61.8F/gatascanrateof2mV/s.Further,thedeviceshowedexcellentlongtermstabilityfor20,000cycleswith88%capacitanceretentionatahighcurrentdensityof25A/g.

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  • 简介:AbstractBackgroundStudies have reported that low bone mineral density (BMD) is prevalent in human immunodeficiency virus (HIV)-infected patients; however, the factors that contribute to HIV-related BMD changes are yet to be fully understood. Due to the application of dual X-ray absorptiometry (DXA) among a select group of hospitals only, the prevalence and risk factors of low BMD in HIV-infected populations have not been intensively investigated in China. Thus, the aim of our study was to investigate the prevalence of and risk factors associated with BMD changes among antiretroviral therapy (ART)-naive HIV-positive patients in China.MethodsThe assessment of the prevalence of and risk factors associated with BMD changes was conducted among 156 ART-naive HIV-infected patients. Demographic and clinical data, as well as results of fasting blood tests were obtained from patients. Further, all patients underwent DXA scans to determine BMD, which was then used to classify patients with osteopenia/osteoporosis. The risk factors of reduced BMD were then evaluated using binary logistic regression.ResultsAmong the 156 ART-naive HIV-infected participants, osteopenia and osteoporosis were diagnosed in 48.7% (76/156) and 4.5% (7/156) of patients, respectively. The lumbar spine was most likely to have reduced BMD (49.4% [77/156]), and the proportion of osteopenia in the left hip (32.7% [51/156]) was higher than in the right hip (24.4% [38/156]). In the lumbar spine, bone loss rate in the L1 section (60.9% [95/156]) was the most significant (L2, 53.2% [83/156]; L3, 45.5% [71/156]; L4, 52.6% [82/156]). Further analysis showed that, compared with the neck (26.9% [42/156] in the left, 18.6% [29/156] in the right) and the interior (15.4% [24/156] in the left, 13.5% [21/156] in the right), the trochanter had the greatest probability of reduced BMD (46.2% [72/156] in the left, 28.8% [45/156] in the right). In the risk factor analysis, low body mass index (BMI: <18.5 kg/m2) was positively associated with reduced BMD (Exp (B) = 39.743, 95 % confidence interval: 3.234-488.399, P = 0.004), and was specifically positively correlated with BMD values at three sites (r = 0.335 at right hip, r = 0.327 at left hip, r = 0.311 at lumbar spine).ConclusionReduced BMD was found in the majority of ART-naive HIV-infected patients and BMI was identified as an additional risk factor for reduced BMD. Our results show that BMD reduction was simultaneously present in the left hip, right hip, and lumbar spine among nearly one fifth of patients. Our work highlights the importance of closely monitoring BMD in ART-naive patients and provides a foundation for the clinical intervention of bone demineralization in them.

  • 标签: Human immunodeficiency virus (HIV) Antiretroviral therapy-naive Bone mineral density Body mass index
  • 简介:这篇评论文章在大气、海洋的研究与进化的全面历史的评论和各种各样的密度表面的申请开始。Thebackground为中立密度想法的出生提供一个基础。注意从海水的状态的方程的非线性对中立密度表面概念的发展被给予。中立密度表面的定义和性质是当摆平的快活频率N~2是零时,从海水和快活频率的状态的方程发展了详细被描述,稳定性的一个中立状态。以便把中立密度表面用于中间的水团分析,这评论也详细描述它的实际海洋学的应用程序。印射的技术第一次集中于定期在这评论使用gridded数据。一根脊梁和肋骨框架怎么被设计从在世界的海洋扔并且首先印射全球中立表面的一本参考书充实,被考察。几印射的中立密度表面为每世界海洋表现为例子。Thewater团性质在每海洋被分析在中间深度。中立密度表面的特征与潜在的密度表面的那些相比。

  • 标签: 海水 浮性 麦克道尔 深度
  • 简介:Background:Mostcurrentapproachesinforestscienceandpracticerequireinformationaboutstructureandgrowthofindividualtreesratherthan-orinadditionto-sumandmeanvaluesofgrowthandyieldatforeststandlevelasprovidedbyclassicexperimentaldesigns.Byinventingthewheeldesign,Nelderprovidedthepossibilitytoturntotheindividualtreeasbasicinformationunit.Suchtrialsprovidevaluableinsightsintothedependencyofgrowthonstanddensityatparticularsites.Methods:Here,wepresentanextensionoftheoriginaldesignandevaluationbyNelder.(i)WeestablishedNelderwheelsalonganenvironmentalgradientthroughEuropeinatlanticclimateinBelgiumandGermany,MediterraneanclimateinItaly,continentalclimateinHungaryaswellasonhighlandclimateinMexico.SuchdisjunctNelderwheelsalonganenvironmentalgradientcanberegardedandanalysedasatwo-factordesignwiththefactorsofsiteconditionandstanddensity.(ii)WepresentanadvancedstatisticalapproachtoevaluatedensitydependentgrowthdynamicsoftreesplantedinformoftheNelderdesign,whichconsidersspatio-temporalautocorrelation.(iii)Weprovetheusefulnessofthemethodsinimprovingecologicaltheoryconcerningdensityrelatedproductivity,trade-offsbetweenfacilitationandcompetition,andallometricrelationsbetweensizevariables.Results:FirstevaluationsbasedonremeasuredNelderwheelsinoak(QuercusroburL.)showasizegrowthdifferentiationduringthefirstobservationperiod.Inparticular,heightgrowthisacceleratedunderhighercompetitionindicatingfacilitationeffects.Wedetectfurthermoreahighvariabilityinallometricrelations.Conclusions:Theproposeddesign,methods,andresultsarediscussedregardingtheirimpactonforestpractice,modelbuilding,andecologicaltheory.WeconcludethattheextendedNelderapproachishighlyefficientinprovidingcurrentlylackingindividualtreelevelinformation.

  • 标签: FACILITATION LONG-TERM TRIAL Nelder Single tree
  • 简介:AbstractDespite overwhelming evidence from large randomized clinical trials supporting a clear benefit of low-density lipoprotein cholesterol (LDL-C) lowering therapy on the primary and secondary prevention of atherosclerotic cardiovascular disease, data from epidemiological and clinical observations demonstrated an increased incidence of hemorrhagic stroke in patients with low LDL-C exposure (<70 mg/dL), especially among East Asians. Meanwhile, emerging studies have reported a paradoxical phenomenon in which hypercholesterolemia is associated with better short-term outcomes in acute coronary syndrome patients, the "lipid paradox." The underlying mechanism for these two closely connected clinical observations is not clear. This review aimed to summarize the evolution and clinical implications of these two low LDL-C related concepts, and proposed a "double-hit" hypothesis that may help explain these phenomena. It is worth noting that in the era of increasing use of high-intensity LDL-C lowering and dual antiplatelet strategies in atherosclerotic cardiovascular disease in patients receiving percutaneous coronary intervention, balancing the risk of thrombosis with bleeding complication should be a priority in clinical practice. Our hypothesis may raise clinicians’ awareness to identify potential high risk patients with low LDL-C (<70 mg/dL), especially among East Asians.

  • 标签: acute coronary syndrome bleeding hemorrhagic stroke lipid paradox risk factor
  • 简介:Background:Treespeciesrecognitionisthemainbottleneckinremotesensingbasedinventoriesaimingtoproduceaninputforspecies-specificgrowthandyieldmodels.Wehypothesizedthatastratificationofthetargetdataaccordingtothedominantspeciescouldimprovethesubsequentpredictionsofspecies-specificattributesinparticularinstudyareasstronglydominatedbycertainspecies.Methods:Wetestedthishypothesisandanoperationalpotentialtoimprovethepredictionsoftimbervolumes,stratifiedtoScotspine,Norwayspruceanddeciduoustrees,inaconiferforestdominatedbythepinespecies.Wederivedpredictorfeaturesfromairbornelaserscanning(ALS)dataandusedMostSimilarNeighbor(MSN)andSeeminglyUnrelatedRegression(SUR)asexamplesofnon-parametricandparametricpredictionmethods,respectively.Results:TherelationshipsbetweentheALSfeaturesandthevolumesoftheaforementionedspecieswereconsiderablydifferentdependingonthedominantspecies.Incorporatingtheobserveddominantspeciesinthepredictionsimprovedtherootmeansquarederrorsby13.3-16.4%and12.6-28.9%basedonMSNandSUR,respectively,dependingonthespecies.Predictingthedominantspeciesbasedonalineardiscriminantanalysishadanoverallaccuracyofonly76%atbest,whichdegradedtheaccuraciesofthepredictedvolumes.Consequently,thepredictionsthatdidnotconsiderthedominantspeciesweremoreaccuratethanthoserefinedwiththepredictedspecies.TheMSNmethodgaveslightlybetterresultsthanmodelsfittedwithSUR.Conclusions:Accordingtoourresults,incorporatinginformationonthedominantspecieshasaclearpotentialtoimprovethesubsequentpredictionsofspecies-specificforestattributes.DeterminingthedominantspeciesbasedsolelyonALSdataisdeemedchallenging,butimportantinparticularinareaswherethespeciescompositionisotherwiseseeminglyhomogeneousexceptbeingdominatedbycertainspecies.

  • 标签: 机载激光扫描 预测功能 优势树种 激光扫描数据 木材 疏密度
  • 简介:Theequilibriumgeometries,relativestabilities,andelectronicpropertiesofMnAgm(M=Na,Li;n+m≤7)aswellaspureAgn,Nan,Lin(n≤7)clustersaresystematicallyinvestigatedbymeansofthedensityfunctionaltheory.Theoptimizedgeometriesrevealthatfor2≤n≤7,therearesignificantsimilaritiesingeometryamongpureAgn,Nan,andLinclusters,andthetransitionsfromplanartothree-dimensionalconfigurationsoccuratn=7,7,and6,respectively.Incontrast,thefirstthree-dimensional(3D)structuresareobservedatn+m=5forbothNanAgmandLinAgmclusters.Whenn+m≥5,astrikingfeatureisthatthetrigonalbipyramidbecomesthemainsubunitofLinAgm.Furthermore,dramaticodd-evenalternativebehavioursareobtainedinthefragmentationenergies,secondorderdifferenceenergies,highestoccupiedandlowestunoccupiedmolecularorbitalenergygaps,andchemicalhardnessforbothpureanddopedclusters.Theanalyticresultsexhibitthatclusterswithanevenelectronicconfiguration(2,4,6)possesstheweakestchemicalreactivityandmoreenhancedstability.

  • 标签: Mn Agm(M=Na Li) CLUSTERS density functional