To attain the volumetric information of the optic radiation in normal human brains, we per- formed diffusion tensor imaging examination in 13 healthy volunteers. Simultaneously, we used a brain normalization method to...To attain the volumetric information of the optic radiation in normal human brains, we per- formed diffusion tensor imaging examination in 13 healthy volunteers. Simultaneously, we used a brain normalization method to reduce individual brain variation and increase the accuracy of volumetric information analysis. In addition, tractography-based group mapping method was also used to investigate the probability and distribution of the optic radiation pathways. Our results showed that the measured optic radiation fiber tract volume was a range of about 0.16% and that the fractional anisotropy value was about 0.53. Moreover, the optic radiation probability fiber pathway that was determined with diffusion tensor tractography-based group mapping was able to detect the location relatively accurately. We believe that our methods and results are help- ful in the study of optic radiation fiber tract information.展开更多
电力线和无线混合通信可以优势互补提升电力物联网室内覆盖的综合性能。针对无线接入和电力线中继的混合通信场景,文章提出一种适用于两跳混合中继的通用MAC层算法。综合考虑物理层信道参数和MAC层的载波侦听多路访问(carrier sense mul...电力线和无线混合通信可以优势互补提升电力物联网室内覆盖的综合性能。针对无线接入和电力线中继的混合通信场景,文章提出一种适用于两跳混合中继的通用MAC层算法。综合考虑物理层信道参数和MAC层的载波侦听多路访问(carrier sense multiple access,CSMA)退避流程,建立了该MAC层算法的跨层性能分析模型,推导了两跳传输系统归一化吞吐量以及系统时延等性能;最后仿真验证了算法有效性和模型准确性,分析了物理层和MAC层关键参数影响系统性能的机理。与Basic-RTS/CTS算法相比,所提算法可有效提升系统吞吐量和时延性能。展开更多
目的探讨肺动脉血管造影(CTPA)在评估急性肺栓塞(APE)患者右心功能变化的临床应用价值。方法检索Pubmed、Embase、Web of Science、Cochrane、万方、维普和中国知网等数据库中关于CTPA分析APE患者右心功能的临床对照研究,时限为2000年1...目的探讨肺动脉血管造影(CTPA)在评估急性肺栓塞(APE)患者右心功能变化的临床应用价值。方法检索Pubmed、Embase、Web of Science、Cochrane、万方、维普和中国知网等数据库中关于CTPA分析APE患者右心功能的临床对照研究,时限为2000年1月至2023年2月。文献筛选后,以纽卡斯尔-渥太华量表(NOS)评估文献质量,Review Manager 5.4软件进行meta分析。结果与无APE患者相比,APE患者右心室与左心室最大直径比(RVd/LVd)(SMD=1.25,95%CI:0.94~1.56,P<0.05)、右心室与左心室最大截面积比(SMD=0.80,95%CI:0.71~0.89,P<0.05)、右心室与左心室容积比(SMD=1.42,95%CI:0.44~2.40,P<0.05)和右心室与左心室之间的最大距离比(SMD=0.91,95%CI:0.57~1.25,P<0.05)均明显增大。中央型APE患者RVd/LVd明显高于周围型APE患者(SMD=1.73,95%CI:0.95~2.51,P<0.05)。结论CTPA对APE右心功能情况具有良好的评估价值。展开更多
文摘To attain the volumetric information of the optic radiation in normal human brains, we per- formed diffusion tensor imaging examination in 13 healthy volunteers. Simultaneously, we used a brain normalization method to reduce individual brain variation and increase the accuracy of volumetric information analysis. In addition, tractography-based group mapping method was also used to investigate the probability and distribution of the optic radiation pathways. Our results showed that the measured optic radiation fiber tract volume was a range of about 0.16% and that the fractional anisotropy value was about 0.53. Moreover, the optic radiation probability fiber pathway that was determined with diffusion tensor tractography-based group mapping was able to detect the location relatively accurately. We believe that our methods and results are help- ful in the study of optic radiation fiber tract information.
文摘电力线和无线混合通信可以优势互补提升电力物联网室内覆盖的综合性能。针对无线接入和电力线中继的混合通信场景,文章提出一种适用于两跳混合中继的通用MAC层算法。综合考虑物理层信道参数和MAC层的载波侦听多路访问(carrier sense multiple access,CSMA)退避流程,建立了该MAC层算法的跨层性能分析模型,推导了两跳传输系统归一化吞吐量以及系统时延等性能;最后仿真验证了算法有效性和模型准确性,分析了物理层和MAC层关键参数影响系统性能的机理。与Basic-RTS/CTS算法相比,所提算法可有效提升系统吞吐量和时延性能。
文摘目的探讨肺动脉血管造影(CTPA)在评估急性肺栓塞(APE)患者右心功能变化的临床应用价值。方法检索Pubmed、Embase、Web of Science、Cochrane、万方、维普和中国知网等数据库中关于CTPA分析APE患者右心功能的临床对照研究,时限为2000年1月至2023年2月。文献筛选后,以纽卡斯尔-渥太华量表(NOS)评估文献质量,Review Manager 5.4软件进行meta分析。结果与无APE患者相比,APE患者右心室与左心室最大直径比(RVd/LVd)(SMD=1.25,95%CI:0.94~1.56,P<0.05)、右心室与左心室最大截面积比(SMD=0.80,95%CI:0.71~0.89,P<0.05)、右心室与左心室容积比(SMD=1.42,95%CI:0.44~2.40,P<0.05)和右心室与左心室之间的最大距离比(SMD=0.91,95%CI:0.57~1.25,P<0.05)均明显增大。中央型APE患者RVd/LVd明显高于周围型APE患者(SMD=1.73,95%CI:0.95~2.51,P<0.05)。结论CTPA对APE右心功能情况具有良好的评估价值。
