Quasi-periodic solutions with multiple base frequencies exhibit the feature of 2π-periodicity with respect to each of the hyper-time variables.However,it remains a challenge work,due to the lack of effective solution...Quasi-periodic solutions with multiple base frequencies exhibit the feature of 2π-periodicity with respect to each of the hyper-time variables.However,it remains a challenge work,due to the lack of effective solution methods,to solve and track the quasi-periodic solutions with multiple base frequencies until now.In this work,a multi-steps variable-coefficient formulation is proposed,which provides a unified framework to enable either harmonic balance method or collocation method or finite difference method to solve quasi-periodic solutions with multiple base frequencies.For this purpose,a method of alternating U and S domain is also developed to efficiently evaluate the nonlinear force terms.Furthermore,a new robust phase condition is presented for all of the three methods to make them track the quasi-periodic solutions with prior unknown multiple base frequencies,while the stability of the quasi-periodic solutions is assessed by mean of Lyapunov exponents.The feasibility of the constructed methods under the above framework is verified by application to three nonlinear systems.展开更多
背景与目的:BRCA1突变与三阴性乳腺癌发病相关目前己得到学者公认。该研究旨在分析BRCA1相关A蛋白复合物相关基因的单核苷酸多态性(single nucleotide polymorphisms,SNP)与三阴性乳腺癌发病风险的关系,寻找和确定与汉族人群三阴性乳腺...背景与目的:BRCA1突变与三阴性乳腺癌发病相关目前己得到学者公认。该研究旨在分析BRCA1相关A蛋白复合物相关基因的单核苷酸多态性(single nucleotide polymorphisms,SNP)与三阴性乳腺癌发病风险的关系,寻找和确定与汉族人群三阴性乳腺癌遗传易感性相关的基因型和单体型。方法:2008年-2011年间414例在复旦大学附属肿瘤医院接受原发性乳腺癌手术的三阴性乳腺癌患者和354例健康妇女进入本病例对照研究。通过对Abraxas、BRE、Rap80、NBA1和BRCC36基因组DNA的37个SNP位点的检测,分析它们与三阴性乳腺癌的相关性。研究者随后检测了652例其他类型乳腺癌和890例健康女性的DNA以证实发现的SNP是否为三阴性特有的遗传相关位点。结果:该研究在第一步研究中发现,NBA1启动子区rs7250266位点突变的G等位基因在三阴性乳腺癌患者中的频率显著低于在正常女性中的频率(0.14 vs 0.19,P〈0.01)。对rs7250266位点基因分型显示:与携带cc基因型个体比较,携带GC型个体的三阴性乳腺癌的发病风险显著降低(GC:OR=0.70,95%CI:0.51~0.97;GG:OR=0.48,95%CI:0.21~1.07,P=0.03)。单体型分析也证实NBA1基因的不同单体型间三阴性乳腺癌发病风险不同。第二步的研究结果显示,rs7250266位点突变在非三阴性的乳腺癌与正常人群中差异无统计学意义(0.19 vs 0.18,P=0.85)。结论:NBA1基因的rs7250266位点的单核苷酸多态性与汉族女性的三阴性乳腺癌发病风险相关,其突变型等位基因携带者罹患三阴性乳腺癌的风险低于野生型等位基因携带者。展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.12172267 and 12302014).
文摘Quasi-periodic solutions with multiple base frequencies exhibit the feature of 2π-periodicity with respect to each of the hyper-time variables.However,it remains a challenge work,due to the lack of effective solution methods,to solve and track the quasi-periodic solutions with multiple base frequencies until now.In this work,a multi-steps variable-coefficient formulation is proposed,which provides a unified framework to enable either harmonic balance method or collocation method or finite difference method to solve quasi-periodic solutions with multiple base frequencies.For this purpose,a method of alternating U and S domain is also developed to efficiently evaluate the nonlinear force terms.Furthermore,a new robust phase condition is presented for all of the three methods to make them track the quasi-periodic solutions with prior unknown multiple base frequencies,while the stability of the quasi-periodic solutions is assessed by mean of Lyapunov exponents.The feasibility of the constructed methods under the above framework is verified by application to three nonlinear systems.
文摘背景与目的:BRCA1突变与三阴性乳腺癌发病相关目前己得到学者公认。该研究旨在分析BRCA1相关A蛋白复合物相关基因的单核苷酸多态性(single nucleotide polymorphisms,SNP)与三阴性乳腺癌发病风险的关系,寻找和确定与汉族人群三阴性乳腺癌遗传易感性相关的基因型和单体型。方法:2008年-2011年间414例在复旦大学附属肿瘤医院接受原发性乳腺癌手术的三阴性乳腺癌患者和354例健康妇女进入本病例对照研究。通过对Abraxas、BRE、Rap80、NBA1和BRCC36基因组DNA的37个SNP位点的检测,分析它们与三阴性乳腺癌的相关性。研究者随后检测了652例其他类型乳腺癌和890例健康女性的DNA以证实发现的SNP是否为三阴性特有的遗传相关位点。结果:该研究在第一步研究中发现,NBA1启动子区rs7250266位点突变的G等位基因在三阴性乳腺癌患者中的频率显著低于在正常女性中的频率(0.14 vs 0.19,P〈0.01)。对rs7250266位点基因分型显示:与携带cc基因型个体比较,携带GC型个体的三阴性乳腺癌的发病风险显著降低(GC:OR=0.70,95%CI:0.51~0.97;GG:OR=0.48,95%CI:0.21~1.07,P=0.03)。单体型分析也证实NBA1基因的不同单体型间三阴性乳腺癌发病风险不同。第二步的研究结果显示,rs7250266位点突变在非三阴性的乳腺癌与正常人群中差异无统计学意义(0.19 vs 0.18,P=0.85)。结论:NBA1基因的rs7250266位点的单核苷酸多态性与汉族女性的三阴性乳腺癌发病风险相关,其突变型等位基因携带者罹患三阴性乳腺癌的风险低于野生型等位基因携带者。
