目的分析引起吉林省2009年手足口病(Hand,Footand Mouth Disease,HFMD)流行的柯萨奇病毒A组16型(Coxsackievirus Group A Type16,CVA16)VP1编码区的基因特征。方法 对2009年分离于吉林省部分HFMD来源的15株CVA16分离株的VP1编码区基因...目的分析引起吉林省2009年手足口病(Hand,Footand Mouth Disease,HFMD)流行的柯萨奇病毒A组16型(Coxsackievirus Group A Type16,CVA16)VP1编码区的基因特征。方法 对2009年分离于吉林省部分HFMD来源的15株CVA16分离株的VP1编码区基因,进行逆转录-聚合酶链反应扩增,并对扩增产物进行序列测定,使用Bioedit软件和MEGA4.0软件对VP1编码区基因进行基因遗传进化及同源性分析。结果吉林省2009年15株CVA16分离株有86.7%(13/15)属于B1a基因亚型,13.3%(2/15)属于B1b基因亚型,并且15株分离株分属于3个相对独立的传播链(Clade1～3),分别由11株、2株、2株组成。3个传播链各自的组内核苷酸和氨基酸同源性均较高,其中较大优势传播链(Clade1)的核苷酸和氨基酸同源性均高达98.2%～100.0%,两个较小传播链均高达100%。结论吉林省2009年监测到至少有2个基因亚型、3个传播链的CVA16引起的HFMD流行,并且呈现以1个B1a基因亚型的优势传播链为主,其他2个小传播链为辅的传播模式。无论是优势传播链还是小传播链,均各自呈现密切的亲缘关系。展开更多
Recently, direct acquisition of GPS P-code has received considerable attention to enhance the anti-jamming and anti-spoofing capabilities of GPS receivers. This paper describes a P-code acquisition method that uses bl...Recently, direct acquisition of GPS P-code has received considerable attention to enhance the anti-jamming and anti-spoofing capabilities of GPS receivers. This paper describes a P-code acquisition method that uses block searches with large-scale FFT to search code phases and carrier frequency offsets in parallel. To limit memory use, especially when implemented in hardware, only the largest correlation result with its position information was preserved after searching a block of resolution cells in both the time and frequency domains. A second search was used to solve the code phase slip problem induced by the code frequency offset, Simulation results demonstrate that the probability of detection is above 0.99 for carrier-to-noise density ratios in excess of 40 dB. Hz when the predetection integration time is 0.8 ms and 6 non- coherent integrations are used in the analysis.展开更多
文摘目的分析引起吉林省2009年手足口病(Hand,Footand Mouth Disease,HFMD)流行的柯萨奇病毒A组16型(Coxsackievirus Group A Type16,CVA16)VP1编码区的基因特征。方法 对2009年分离于吉林省部分HFMD来源的15株CVA16分离株的VP1编码区基因,进行逆转录-聚合酶链反应扩增,并对扩增产物进行序列测定,使用Bioedit软件和MEGA4.0软件对VP1编码区基因进行基因遗传进化及同源性分析。结果吉林省2009年15株CVA16分离株有86.7%(13/15)属于B1a基因亚型,13.3%(2/15)属于B1b基因亚型,并且15株分离株分属于3个相对独立的传播链(Clade1～3),分别由11株、2株、2株组成。3个传播链各自的组内核苷酸和氨基酸同源性均较高,其中较大优势传播链(Clade1)的核苷酸和氨基酸同源性均高达98.2%～100.0%,两个较小传播链均高达100%。结论吉林省2009年监测到至少有2个基因亚型、3个传播链的CVA16引起的HFMD流行,并且呈现以1个B1a基因亚型的优势传播链为主,其他2个小传播链为辅的传播模式。无论是优势传播链还是小传播链,均各自呈现密切的亲缘关系。
文摘Recently, direct acquisition of GPS P-code has received considerable attention to enhance the anti-jamming and anti-spoofing capabilities of GPS receivers. This paper describes a P-code acquisition method that uses block searches with large-scale FFT to search code phases and carrier frequency offsets in parallel. To limit memory use, especially when implemented in hardware, only the largest correlation result with its position information was preserved after searching a block of resolution cells in both the time and frequency domains. A second search was used to solve the code phase slip problem induced by the code frequency offset, Simulation results demonstrate that the probability of detection is above 0.99 for carrier-to-noise density ratios in excess of 40 dB. Hz when the predetection integration time is 0.8 ms and 6 non- coherent integrations are used in the analysis.
