简介:着重探讨利用ARCGISVBA程序,快速、高效地对不同比例尺框架要素数据更新数据进行一致性、存在性质量检验,以及对框架要素数据库中重要要素进行重点检查的思路,以确保该数据库具有现势性、准确性与权成性。
简介:Anovelautomaticseamlessstitchingmethodispresented.Comparedtothetraditionalmethod,itcanspeedtheprocessingandminimizetheutilizationofhumanresourcestoproducegloballunarmap.Meanwhile,anewglobalimagemapoftheMoonwithspatialresolutionof~120mhasbeencompletedbytheproposedmethodfromChang’E-1CCDimagedata.
简介:Cytarabine(1-β-D-arabinofuranosylcytosine,Ara-C),isolatedfromaCaribbeanspongespeciesTethyacrypta,isthefirstantitumordrugfromamarineresource.In1980,theUSFoodandDrugAdministrationapprovedthisdrugforthetreatmentofdifferenttypesofleukemia.Thisdrughasashortplasmahalf-life,lowstability,limitedbioavailability,andseveresideeffects.Toimprovestabilityandbioavailability,wesynthesizedninenovelderivativesbyblockingthecytarabinemetabolicsitesandimprovinglipophilicity.ThecLogPvaluesofthenewlysynthesizedcompoundswerecalculated.Allthesynthesizedcompoundsweremorelipophilicthancytarabine,resultinginmembranepermeabilityandbioavailabilityimprovement.TheantitumoractivitiesagainstleukemiacelllineHL-60wereevaluatedbyusingtheMTTassay.ThebioassayresultsrevealedthattheIC50valuesofcompounds5,8and9were0.080,0.090and0.057μmolL-1,respectively,whichwassimilarwiththatofcytarabine(0.056μmolL-1).Incomparison,compound4withaphosphategroupatO5’wasinactive.Becausephosphoesterbondsareeasilyhydrolyzedbyalkalinephosphataseandarecommonlyusedinproducingprodrugstrategies,compound4mightalsobemetabolizedinvivoandgeneratecompound3orevencytarabinethroughamulti-stepreaction.Thus,compound4mightbeapromisingcompoundtobedevelopedasaprodrug.
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简介:雨效果和缺乏在situ确认,数据是热带气旋风检索错误的二个主要原因。国家海洋、大气的政府气候预言中心Morphing技术(CMORPH)雨率被介绍给配对数据集然后放进一个雨修正模型在Jason-1上移开雨效果规范的雷达十字节(NRCS);飓风研究部门(HRD)风速度,集成所有可得到的表面天气观察,被用来在situ数据代替与Jason-1NRCS建立这种关系。然后,在热带气旋条件下面的一个改进Jason-1风检索算法被建议。从2003~2010的七热带气旋被学习验证新算法。试验性的结果显示在C乐队和Ku乐队的这个算法的标准差分别地是1.99和2.75m/s,它比存在算法好。另外,C乐队算法比在热带气旋条件下面的Ku乐队对海表面风检索更合适。