简介:TheConductorandHardwareResearchDivisionoftheElectricPowerConstructionResearchInstitute,MinistyofEnergy,isascientificresearchandtestbaseforstudyofmechanicalpropertiesoftransmissionlineconductorandhardwareinChina,whichhasahistoryof32yearslong.TheDivisionnowpossessesastaffofabout20,including5seniorengineersand5engineers.TheDivisionpossessesalsoalab,itmainlydealsWiththetestandre-
简介:Thispaperpresentsanewsystemidentificationapproachusingvectorspacebasefunctions,andproposestwonetworkstructuresbasedonGammasequenceandLaguerresequence.Afteranalyzingandcomparingthesestructuresindetail,somesimulationresultstodemonstratetheconclusionsaregiven.
简介:ZnOnanoparticleswithanaveragesizeof125nmwerepreparedviahomogeneousprecipitationmethodandwerecharacterizedbySEM.Theproductsweresurface-modifiedbythesurfactantSDS.Surface-modifiednanoparticleswereaddedatamassratioof1.0%,2.0%,3.0%,and4.0%,respectively,inbaseoilandtheirfrictionandwearbehaviorswereevaluatedonaMRS-10Dtypefour-ballweartester.Afterfour-ballweartests,themorphologyoftherubbingsurfaceswasevaluatedwithmetallographicmicroscope.ItwasrevealedthatthemodifiednanoZnOhadexcellentbehaviorforimprovinganti-wearpropertyandfrictioncoefficient,whichcouldgreatlyreducethefrictionofmachineparts.
简介:AbstractThe development of applications for the CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats/CRISPR-associated nuclease 9) system has increased greatly in recent years, especially in the area of gene therapy by efficient in vivo genome editing. Although great success has been achieved in repairing and rewriting genomes through homology-directed repair coupled with Cas9 nuclease cleavage, its in vivo efficiency is insufficient for gene therapy. Base editing is a next-generation genome-editing tool that does not involve double-stranded DNA breaks and uses components of the CRISPR system together with other enzymes to make point mutations directly in cellular DNA or RNA. Base editors, composed of an engineered deaminase and a catalytically impaired CRISPR/Cas9 variant, are powerful tools for targeted base editing in cells and organisms. In non-dividing cells, base editors can directly transform one base or base pair into another, efficiently installing a point mutation. Undesired by-products of editing are seldom generated during this procedure. Herein we review the different base-editing platforms, including their deaminase recruitment strategies and editing outcomes, and the in vivo delivery of base editors. Additionally, we summarize therapeutic applications of base editing in disorders of the inner ear.
简介:摘要:本文针对学生不易掌握导数含参数问题中参数该如何分类的问题,通过对几个典型问题的探究,结合流程图来对参数的分类方法和含参数问题的求解步骤来进行总结,形成解决此类问题的模式化解题方法。用流程图来体现参数的分类方法,直观明了,易理解,将解题思想流程化,易操作。
简介:摘要目的研究经阴道自然孔道内镜手术(vNOTES)及经脐单孔腹腔镜手术(TU-LESS)行子宫全切除术时的安全性及可行性。方法回顾性分析2018年10月1日至2019年6月30日因子宫良性病变于四川大学华西第二医院行子宫全切除术患者的临床资料,根据手术方式分为vNOTES组和TU-LESS组。对比分析两组患者的手术成功率、子宫体积、手术时间、手术失血量、术中并发症发生率、术后并发症发生率、术后排气时间、术后留置尿管时间、住院时间等临床指标。结果vNOTES组患者30例,TU-LESS组患者77例,两组患者均顺利完成子宫全切除术,无患者更改手术途径,两组的手术成功率均为100%。vNOTES组和TU-LESS组患者的子宫体积[分别为(165±36)、(235±38) cm3,P=0.243]、手术时间[分别为(150±41)、(169±48) min,P=0.063]、手术失血量[分别为(54±15)、(54±14) ml,P=0.985]、术中并发症发生率[分别为3%(1/30)、3%(2/77),P=1.000]、术后并发症发生率[分别为13%(4/30)、4%(3/77),P=0.095]、切除双侧附件的比率[分别为50%(15/30)、31%(24/77),P=0.069]分别比较,差异均无统计学意义(P均>0.05)。两组患者的术后排气时间[分别为(1.7±0.5)、(2.3±0.6) d,P=0.001]、术后留置尿管时间[分别为(1.9±0.4)、(2.3±0.6) d,P=0.004]、住院时间[分别为(3.2±0.8)、(3.6±0.9) d,P=0.045]分别比较,差异均有统计学意义(P均<0.05),vNOTES组患者均短于TU-LESS组。结论vNOTES途径及TU-LESS途径行子宫全切除术时均安全、可行,但vNOTES途径更有利于患者的术后康复,有更小的创伤及最佳的手术无痕效果。
简介:Dendriticgraingrowthattheedgeoftheweldpoolissimulatedusingastochasticnumericalmodelofcellularautomatonalgorithm.Thegraingrowthmodelisestablishedbaseduponthebalanceofsoluteinthesolid/liquidinterfaceofthedendritetip.Consideringthecomplicatednucleationconditionandcompetitivegrowth,thedendritemorphologiesofdifferentnucleationconditionaresimulated.Thesimulatedresultsreproducedthedendritegrainevolutionprocessattheedgeoftheweldpool.Itisindicatedthatthenucleationconditionisanimportantfactorinfluencingthegrainmorphologiesespeciallythemorphologiesofsecondaryandtertiaryarms.