目的探讨信号转导和转录激活因子-3(signal transducer and activator of transcription-3,STAT3)基因单核苷酸多态性(single nucleotide polymorphism,SNP)与重庆地区汉族儿童川崎病(kawasaki disease,KD)易感性的关系。方法用序列特...目的探讨信号转导和转录激活因子-3(signal transducer and activator of transcription-3,STAT3)基因单核苷酸多态性(single nucleotide polymorphism,SNP)与重庆地区汉族儿童川崎病(kawasaki disease,KD)易感性的关系。方法用序列特异性引物聚合酶链反应(sequence specific primers-polymerase chain reaction,SSP-PCR)分析130例重庆地区汉族川崎病患儿及147名健康儿童STAT3基因内含子11(rs2293152C/G和rs957970C/T)的SNP,统计学分析病例组与对照组之间的差异。结果川崎病组STAT3基因rs2293152C/G位点CC基因型频率(23.8%)显著高于对照组(10.2%),川崎病组rs2293152C等位基因分布频率(45.4%)显著高于对照组(34.0%,P=0.006,OR=1.612,95%CI:1.144～2.272);而STAT3 rs957970C/T位点基因型及等位基因频率分布在川崎病组和对照组间无统计学差异(P>0.05)。结论重庆地区汉族儿童的STAT3基因内含子11中rs2293152位点多态性与川崎病易感性相关,携带rs2293152C等位基因者比G等位基因携带者易罹患川崎病,而STAT3 rs957970C/T位点多态性与该地区儿童川崎病的易感性无显著相关性。展开更多
The accurate estimation of the rolling element bearing instantaneous rotational frequency(IRF) is the key capability of the order tracking method based on time-frequency analysis. The rolling element bearing IRF can b...The accurate estimation of the rolling element bearing instantaneous rotational frequency(IRF) is the key capability of the order tracking method based on time-frequency analysis. The rolling element bearing IRF can be accurately estimated according to the instantaneous fault characteristic frequency(IFCF). However, in an environment with a low signal-to-noise ratio(SNR), e.g., an incipient fault or function at a low speed, the signal contains strong background noise that seriously affects the effectiveness of the aforementioned method. An algorithm of signal preprocessing based on empirical mode decomposition(EMD) and wavelet shrinkage was proposed in this work. Compared with EMD denoising by the cross-correlation coefficient and kurtosis(CCK) criterion, the method of EMD soft-thresholding(ST) denoising can ensure the integrity of the signal, improve the SNR, and highlight fault features. The effectiveness of the algorithm for rolling element bearing IRF estimation by EMD ST denoising and the IFCF was validated by both simulated and experimental bearing vibration signals at a low SNR.展开更多
文摘目的探讨信号转导和转录激活因子-3(signal transducer and activator of transcription-3,STAT3)基因单核苷酸多态性(single nucleotide polymorphism,SNP)与重庆地区汉族儿童川崎病(kawasaki disease,KD)易感性的关系。方法用序列特异性引物聚合酶链反应(sequence specific primers-polymerase chain reaction,SSP-PCR)分析130例重庆地区汉族川崎病患儿及147名健康儿童STAT3基因内含子11(rs2293152C/G和rs957970C/T)的SNP,统计学分析病例组与对照组之间的差异。结果川崎病组STAT3基因rs2293152C/G位点CC基因型频率(23.8%)显著高于对照组(10.2%),川崎病组rs2293152C等位基因分布频率(45.4%)显著高于对照组(34.0%,P=0.006,OR=1.612,95%CI:1.144～2.272);而STAT3 rs957970C/T位点基因型及等位基因频率分布在川崎病组和对照组间无统计学差异(P>0.05)。结论重庆地区汉族儿童的STAT3基因内含子11中rs2293152位点多态性与川崎病易感性相关,携带rs2293152C等位基因者比G等位基因携带者易罹患川崎病,而STAT3 rs957970C/T位点多态性与该地区儿童川崎病的易感性无显著相关性。
基金Project(51275030)supported by the National Natural Science Foundation of ChinaProject(2016JBM051)supported by the Fundamental Research Funds for the Central Universities,China
文摘The accurate estimation of the rolling element bearing instantaneous rotational frequency(IRF) is the key capability of the order tracking method based on time-frequency analysis. The rolling element bearing IRF can be accurately estimated according to the instantaneous fault characteristic frequency(IFCF). However, in an environment with a low signal-to-noise ratio(SNR), e.g., an incipient fault or function at a low speed, the signal contains strong background noise that seriously affects the effectiveness of the aforementioned method. An algorithm of signal preprocessing based on empirical mode decomposition(EMD) and wavelet shrinkage was proposed in this work. Compared with EMD denoising by the cross-correlation coefficient and kurtosis(CCK) criterion, the method of EMD soft-thresholding(ST) denoising can ensure the integrity of the signal, improve the SNR, and highlight fault features. The effectiveness of the algorithm for rolling element bearing IRF estimation by EMD ST denoising and the IFCF was validated by both simulated and experimental bearing vibration signals at a low SNR.
