In this paper, the existence of strictly positive solutions for N-species nonau- tonom ous Kolm ogorov com petition system s is studied. By applying the Schauder's fixed point theorem som e new sufficient condit...In this paper, the existence of strictly positive solutions for N-species nonau- tonom ous Kolm ogorov com petition system s is studied. By applying the Schauder's fixed point theorem som e new sufficient conditions are established. In particular, for the alm ost periodic system , the existence of strictly positive alm ostperiodic solutions is obtained. Som e previous results are im proved and generalized.展开更多
TWENTY one-year-old Fan Chunmei,a singer from an artensemble of the Chinese People‘s Liberation Army,won firstprize in the fourth Sound of Asia International Popular SongCompetition,held in Kazakhstan on July 19.Ai J...TWENTY one-year-old Fan Chunmei,a singer from an artensemble of the Chinese People‘s Liberation Army,won firstprize in the fourth Sound of Asia International Popular SongCompetition,held in Kazakhstan on July 19.Ai Jing,from LiaoningProvince,won the Alma-Ata Mayor’s Prize.She sang“My 1997.”Yuan Chenyie of the China Opera Theater took second prize inthe Classical division of the Tokyo International Vocal Music Com-petition,held in Tokyo in June this year.展开更多
In thispaper,theexistence oftravelling frontsolution fora classofcom petition-diffu- sion system w ith high-order singular point w it = diw ixx - w αii fi(w ),x ∈R,t> 0,i= 1,2 (Ⅰ) is studied,w here di,αi>...In thispaper,theexistence oftravelling frontsolution fora classofcom petition-diffu- sion system w ith high-order singular point w it = diw ixx - w αii fi(w ),x ∈R,t> 0,i= 1,2 (Ⅰ) is studied,w here di,αi> 0 (i= 1,2) and w = (w 1(x,t),w 2(x,t)).Under the certain assum ptions on f,itis show ed thatifαi< 1 for som e i,then (Ⅰ) has no travelling frontsolution,ifαi≥1 for i= 1,2,then there isa c0,c:c0≥c> 0,w herecis called the m inim alwavespeed of(Ⅰ),such thatifc≥c0 orc= c,then (Ⅰ) has a travelling frontsolution,ifc< c,then (Ⅰ) hasno travel- ling frontsolution by using the shooting m ethod in com bination w ith a com pactness argum ent.展开更多
为实现小反刍兽疫病毒(Peste des petits ruminants virus,PPRV)的快速、准确、定量检测,以国内PPRV Clone 9疫苗株N基因为靶位点设计特异性引物及探针,建立了液滴式数字PCR(Droplet digital PCR,ddPCR)方法,并对其特异性、敏感性及重...为实现小反刍兽疫病毒(Peste des petits ruminants virus,PPRV)的快速、准确、定量检测,以国内PPRV Clone 9疫苗株N基因为靶位点设计特异性引物及探针,建立了液滴式数字PCR(Droplet digital PCR,ddPCR)方法,并对其特异性、敏感性及重复性进行评价。将所建立的ddPCR方法与实时荧光定量PCR(Fluorescence quantitative PCR,qPCR)方法的灵敏度进行比较分析并应用于PPRV(Clone 9株)核糖核酸标准物质的定量。结果显示,所建立的ddPCR方法特异性好,仅PPRV检测结果为阳性,其他羊源病毒类生物制品及毒种检测结果均为阴性;敏感性高,基因拷贝数检出限度为4.33拷贝/μL,比qPCR方法的灵敏度(57.3拷贝/μL)高10倍;重复性好,重复性试验的变异系数为1.8%;定量准确,具有一定资质的9家单位各组测量数据组间变异系数小于5%。试验建立的ddPCR方法能够有效地对PPRV核酸进行快速检测,为PPRV的诊断及绝对定量提供了有效方法。展开更多
文摘In this paper, the existence of strictly positive solutions for N-species nonau- tonom ous Kolm ogorov com petition system s is studied. By applying the Schauder's fixed point theorem som e new sufficient conditions are established. In particular, for the alm ost periodic system , the existence of strictly positive alm ostperiodic solutions is obtained. Som e previous results are im proved and generalized.
文摘TWENTY one-year-old Fan Chunmei,a singer from an artensemble of the Chinese People‘s Liberation Army,won firstprize in the fourth Sound of Asia International Popular SongCompetition,held in Kazakhstan on July 19.Ai Jing,from LiaoningProvince,won the Alma-Ata Mayor’s Prize.She sang“My 1997.”Yuan Chenyie of the China Opera Theater took second prize inthe Classical division of the Tokyo International Vocal Music Com-petition,held in Tokyo in June this year.
文摘In thispaper,theexistence oftravelling frontsolution fora classofcom petition-diffu- sion system w ith high-order singular point w it = diw ixx - w αii fi(w ),x ∈R,t> 0,i= 1,2 (Ⅰ) is studied,w here di,αi> 0 (i= 1,2) and w = (w 1(x,t),w 2(x,t)).Under the certain assum ptions on f,itis show ed thatifαi< 1 for som e i,then (Ⅰ) has no travelling frontsolution,ifαi≥1 for i= 1,2,then there isa c0,c:c0≥c> 0,w herecis called the m inim alwavespeed of(Ⅰ),such thatifc≥c0 orc= c,then (Ⅰ) has a travelling frontsolution,ifc< c,then (Ⅰ) hasno travel- ling frontsolution by using the shooting m ethod in com bination w ith a com pactness argum ent.
