目的探讨Lorenz散点图(LPs)矢量角的价值,及其联合B线斜率在提高心律失常诊断效能方面的作用。方法回顾性分析119例室性期前收缩(室早组)、97例室上性期前收缩(室上早组)、52例二度Ⅰ型房室传导阻滞(二度Ⅰ型组)和54例二度Ⅱ型房室/窦...目的探讨Lorenz散点图(LPs)矢量角的价值,及其联合B线斜率在提高心律失常诊断效能方面的作用。方法回顾性分析119例室性期前收缩(室早组)、97例室上性期前收缩(室上早组)、52例二度Ⅰ型房室传导阻滞(二度Ⅰ型组)和54例二度Ⅱ型房室/窦房传导阻滞(二度Ⅱ型组)患者的LPs,测量B线斜率及矢量角,比较各组间的差异。采用受试者工作特征曲线分析B线斜率、矢量角及两者联合在组间的诊断效能并使用MedCalc软件进行统计学比较。使用组内相关系数(ICC)、Bland-Altman图评估B线斜率、矢量角的观察者内和观察者间测量的一致性。结果室早组与室上早组、二度Ⅰ型组与二度Ⅱ型组间比较差异均有统计学意义(P<0.05)。B线斜率、矢量角以及两者联合鉴别室性与室上性期前收缩的曲线下面积(AUC)分别为0.81、0.84、0.87,鉴别二度Ⅰ型与二度Ⅱ型房室/窦房传导阻滞的AUC分别为0.76、0.78、0.80。矢量角的ICC优于B线斜率(观察者内0.99 vs 0.98、观察者间0.97 vs 0.96)。结论矢量角可用于鉴别心律失常类型,且具有较好的观察者内及观察者间一致性。其联合B线斜率诊断心律失常具有较高准确率,为临床诊疗提供了新的参考依据。展开更多
We investigated correlation of the slope of the initial part of P-wave envelope, hypocenter depth and plate boundaries by B-Δ method, which is used to determine epicentral distances in the Japan Meteorological Agency...We investigated correlation of the slope of the initial part of P-wave envelope, hypocenter depth and plate boundaries by B-Δ method, which is used to determine epicentral distances in the Japan Meteorological Agency and Japan Railway Company earthquake early warning(EEW) systems. The Tohoku region was chosen as the study region. 19,899 strong motion data for 265 events with magnitudes in the range from 5.0 to 7.6 from KiK-net(Kiban Kyoshin network) had been collected. The coefficient c to investigate is obtained from the linear relation between log B and log Δ. Compared to the hypocenter depth, the coefficients c of events is more likely to decide by the spatial correlation of the plate boundaries. The differences are likely to be due to earthquake characteristics, since deeper events in the subducting slabs the structural effects are likely to be larger than or comparable to those for shallow crust events.展开更多
基于微型光谱仪搭建一台体积小、易操作的猕猴桃可溶性固形物含量(soluble solids content,SSC)检测装置,并用该装置采集了‘华优’、‘徐香’和‘西选’3个品种猕猴桃的近红外光谱,利用不同特征波长提取方法从全光谱中提取特征波长,并...基于微型光谱仪搭建一台体积小、易操作的猕猴桃可溶性固形物含量(soluble solids content,SSC)检测装置,并用该装置采集了‘华优’、‘徐香’和‘西选’3个品种猕猴桃的近红外光谱,利用不同特征波长提取方法从全光谱中提取特征波长,并比较不同方法提取的特征波长及全光谱对3个品种猕猴桃SSC的偏最小二乘模型预测精度的影响;用斜率/截距算法结合‘华优’猕猴桃大样本模型,预测‘徐香’和‘西选’猕猴桃的SSC。结果表明,连续投影算法对于模型简化效果最好,其对‘华优’、‘徐香’和‘西选’猕猴桃大样本的预测均方根误差(root mean square error of prediction,RMSEP)分别为0.583、0.678°Brix和0.646°Brix;用斜率/截距算法对‘华优’猕猴桃SSC模型进行校正时,仅用10个‘徐香’和50个‘西选’猕猴桃便能有效地提高对SSC的预测性能,其RMSEP分别为0.966°Brix和0.875°Brix。本研究为进一步构建精度更高、更便捷的微型集成式猕猴桃SSC检测仪提供理论依据。展开更多
文摘目的探讨Lorenz散点图(LPs)矢量角的价值,及其联合B线斜率在提高心律失常诊断效能方面的作用。方法回顾性分析119例室性期前收缩(室早组)、97例室上性期前收缩(室上早组)、52例二度Ⅰ型房室传导阻滞(二度Ⅰ型组)和54例二度Ⅱ型房室/窦房传导阻滞(二度Ⅱ型组)患者的LPs,测量B线斜率及矢量角,比较各组间的差异。采用受试者工作特征曲线分析B线斜率、矢量角及两者联合在组间的诊断效能并使用MedCalc软件进行统计学比较。使用组内相关系数(ICC)、Bland-Altman图评估B线斜率、矢量角的观察者内和观察者间测量的一致性。结果室早组与室上早组、二度Ⅰ型组与二度Ⅱ型组间比较差异均有统计学意义(P<0.05)。B线斜率、矢量角以及两者联合鉴别室性与室上性期前收缩的曲线下面积(AUC)分别为0.81、0.84、0.87,鉴别二度Ⅰ型与二度Ⅱ型房室/窦房传导阻滞的AUC分别为0.76、0.78、0.80。矢量角的ICC优于B线斜率(观察者内0.99 vs 0.98、观察者间0.97 vs 0.96)。结论矢量角可用于鉴别心律失常类型,且具有较好的观察者内及观察者间一致性。其联合B线斜率诊断心律失常具有较高准确率,为临床诊疗提供了新的参考依据。
基金supported by the Director Foundation of the Institute of Seismology,China Earthquake Administration,China(IS200756046)
文摘We investigated correlation of the slope of the initial part of P-wave envelope, hypocenter depth and plate boundaries by B-Δ method, which is used to determine epicentral distances in the Japan Meteorological Agency and Japan Railway Company earthquake early warning(EEW) systems. The Tohoku region was chosen as the study region. 19,899 strong motion data for 265 events with magnitudes in the range from 5.0 to 7.6 from KiK-net(Kiban Kyoshin network) had been collected. The coefficient c to investigate is obtained from the linear relation between log B and log Δ. Compared to the hypocenter depth, the coefficients c of events is more likely to decide by the spatial correlation of the plate boundaries. The differences are likely to be due to earthquake characteristics, since deeper events in the subducting slabs the structural effects are likely to be larger than or comparable to those for shallow crust events.
文摘基于微型光谱仪搭建一台体积小、易操作的猕猴桃可溶性固形物含量(soluble solids content,SSC)检测装置,并用该装置采集了‘华优’、‘徐香’和‘西选’3个品种猕猴桃的近红外光谱,利用不同特征波长提取方法从全光谱中提取特征波长,并比较不同方法提取的特征波长及全光谱对3个品种猕猴桃SSC的偏最小二乘模型预测精度的影响;用斜率/截距算法结合‘华优’猕猴桃大样本模型,预测‘徐香’和‘西选’猕猴桃的SSC。结果表明,连续投影算法对于模型简化效果最好,其对‘华优’、‘徐香’和‘西选’猕猴桃大样本的预测均方根误差(root mean square error of prediction,RMSEP)分别为0.583、0.678°Brix和0.646°Brix;用斜率/截距算法对‘华优’猕猴桃SSC模型进行校正时,仅用10个‘徐香’和50个‘西选’猕猴桃便能有效地提高对SSC的预测性能,其RMSEP分别为0.966°Brix和0.875°Brix。本研究为进一步构建精度更高、更便捷的微型集成式猕猴桃SSC检测仪提供理论依据。
