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简介:UsingtheefectiveHamiltonianmethod,weanalyzetheB0-ˉB0mixingintheextensionofthestandardmodel(SM)wherebaryonnumberandleptonnumberarelocalgaugesymmetries.ThenumericalresultsindicatethecorrectionfromtheextraparticlestothemassdiferencemBissignificant.Thereisa60%enhancementcomparedtotheSMpredictionformBatmost,whichagreeswiththecurrentexperimentalresult.
简介:TheemergenceofB2Belectronicmarketshasgreatlychangedtherelativebargainingpowerofbuyersandsellers.Westudytheequilibriummarketstructureinabuyer’smarket.Wefindthatbuyer-controlledB2BmarketsandneutralB2Bmarketshavedifferentequilibriumstructures,andtheemergenceofB2Bmarketswillincreasesocialwelfare,butitseffectonbuyersandsellerswillbedifferent:B2Bmarketsincreasetheconsumersurplusoftheendmarket,buttheireffectsonbuyerandsellerprofitsaremoderatedbytherelativebargainingpowerofbuyersandsellers.TheprofitsofthesidewithmuchweakerbargainingpowerwilldecreaseduetotheintroductionofB2Bmarkets.
简介:美国拥有B2B的微软、IBM、甲骨文等科技巨头,中国在此领域却没有一家市值过百亿美元的互联网科技公司,这为中国B2B领域出现巨无霸的巨头提供了无限的遐想。B2C端电商领域在2015年之后市场已经趋向饱和,淘宝、天猫、京东虽然依旧强势,但扩张的步伐已经明显趋缓,对于GMV增长贡献大部分依赖业务板块的横向拓展而非纵向的渗透。至于两大巨头之外的垂直电商平台,唯品会、苏宁云商、一号店、聚美优品等也褪尽黑马本色逐渐进入了瓶颈期。平台电商之外,O2O模式在风起云涌极度喧哗之后集体失语——生鲜领域几乎全军覆没,服务类O2O对于盈利模式也是苦苦探寻;
简介:Thefeaturesofthelow-lyingspectraoffour-bodyA+B-A+B-systemshavebeendeducedbasedonsymmetry.Usingthemethodoffew-bodyphysics,wecalculatetheenergyspectraofA+B-A+B-systemsinaharmonicquantumdot.Wefindthatthebiexcitoninatwo-dimensionalquantumdotmayhaveotherboundexcitedstatesandthequantummechanicalsymmetryplaysacrucialroleindeterminingtheenergylevelsandstructuresofthelow-lyingstates.
简介:摘要目的分析1例白血病患者人类白细胞抗原(human leukocyte antigen,HLA)杂合性丢失情况。方法采用聚合酶链反应序列特异性寡核苷酸探针法和聚合酶链反应测序方法对患者移植后外周血、头发毛囊、口腔黏膜拭子及其父母外周血进行HLA分型。采用23位点短串联重复序列(short tandem repeat, STR)测定试剂盒和本实验室建立的HLA区域内的6个STR位点方法对患者移植后的外周血、口腔黏膜拭子及其父母外周血进行STR位点检测。结果患者经父亲源单倍型造血干细胞移植后,外周血标本HLA基因型与父亲完全一致。患者头发毛囊标本HLA结果为HLA-A*02:01,24:02, C*03:03,03:04, B*13:01,15:01, DRB1*08:03,12:02, DQB1*03:01,06:01。口腔黏膜拭子为HLA纯合子,只存在父亲单倍型HLA-A*24:02-C*03:03-B*15:01-DRB1*08:03-DQB1*06:01,丢失了母亲单倍型HLA-A*02:01-C*03:04-B*13:01-DRB1*12:02-DQB1*03:01。患者移植后外周血23个STR位点与父亲完全一致。口腔黏膜拭子23位点短串联重复位点无丢失,但6号染色体上HLA区域的6个STR位点至少有4个发生了丢失。结论发现1例单倍型造血干细胞移植白血病患者的口腔黏膜拭子发生HLA杂合性丢失。