期刊文献+
共找到2篇文章
< 1 >
每页显示 20 50 100
9个经典Ramsey数R(3,t)的新下界 被引量:4
1
作者 陈红 吴康 +2 位作者 许晓东 苏文龙 梁文忠 《数学杂志》 CSCD 北大核心 2011年第3期582-586,共5页
本文研究了经典Ramsey数R(3,t)的下界问题.利用素数阶循环图的性质改进一般阶循环图团数的计算方法,获得了9个经典Ramsey数R(3,t)的新下界:R(3,29)≥183,R(3,30)≥189,R(3,32)≥213,R(3,33)≥218,R(3,34)≥226,R(3,35)≥231,R(3,36)≥23... 本文研究了经典Ramsey数R(3,t)的下界问题.利用素数阶循环图的性质改进一般阶循环图团数的计算方法,获得了9个经典Ramsey数R(3,t)的新下界:R(3,29)≥183,R(3,30)≥189,R(3,32)≥213,R(3,33)≥218,R(3,34)≥226,R(3,35)≥231,R(3,36)≥239,R(3,37)≥244,R(3,38)≥256,其中前三个结果分别改进了迄今已知的最好的下界,后6个结果是本文首次报道的. 展开更多
关键词 RAMSEY数 下界 循环图
在线阅读 下载PDF
A Novel Interpretation of Structural Dot Plots of Genomes Derived from the Analysis of Two Strains of Neisseria meningitidis
2
作者 Wilfred R. Cuff Venkata R.S.K. Duvvuri +4 位作者 Binhua Liang Bhargavi Duvvuri Gillian E. Wu Jianhong Wu Raymond S.W. Tsang 《Genomics, Proteomics & Bioinformatics》 SCIE CAS CSCD 2010年第3期159-169,共11页
Neisseria meningitidis is the agent of invasive meningococcal disease, including cerebral meningitis and septicemia. Because the diseases caused by different clonal groups (sequence types) have their own epidemiolog... Neisseria meningitidis is the agent of invasive meningococcal disease, including cerebral meningitis and septicemia. Because the diseases caused by different clonal groups (sequence types) have their own epidemiological characteristics, it is important to understand the differences among the genomes of the N. meningitidis clonal groups. To this end, a novel interpretation of a structural dot plot of genomes was devised and applied; exact nu- cleotide matches between the genomes ofN. meningitidis serogroup A strain Z2491 and serogroup B strain MC58 were identified, leading to the specification of various structural regions. Known and putative virulence genes for each N. meningitidis strain were then classified into these regions. We found that virulence genes of MC58 tend more to the translocated regions (chromosomal segments in new sequence contexts) than do those of Z2491, notably tending towards the interface between one of the translocated regions and the collinear region. Within the col- linear region, virulence genes tend to occur within 16 kb of gaps in the exact matches. Verification of these tendencies using genes clustered in the cps locus was sufficiently supportive to suggest that these tendencies can be used to focus the search for and understanding of virulence genes and mechanisms of pathogenicity in these two organisms. 展开更多
关键词 structural dot plots virulence genes TRANSLOCATION match regions mummer Neisseria meningitidis
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部