Exploding foil initiator(EFI)is a kind of advanced device for initiating explosives,but its function is unstable when it comes to directly igniting pyrotechnics.To solve the problem,this research aims to reveal the ig...Exploding foil initiator(EFI)is a kind of advanced device for initiating explosives,but its function is unstable when it comes to directly igniting pyrotechnics.To solve the problem,this research aims to reveal the ignition mechanism of EFIs directly igniting pyrotechnics.An oscilloscope,a photon Doppler velocimetry,and a plasma spectrum measurement system were employed to obtain information of electric characteristics,impact pressure,and plasma temperature.The results of the electric characteristics and the impact pressure were inconsistent with ignition results.The only thing that the ignition success tests had in common was that their plasma all had a relatively long period of high-temperature duration(HTD).It eventually concludes that the ignition mechanism in this research is the microconvection heat transfer rather than the shock initiation,which differs from that of exploding foil initiators detonating explosives.Furthermore,the methods for evaluating the ignition success of semiconductor bridge initiators are not entirely applicable to the tests mentioned in this paper.The HTD is the critical parameter for judging the ignition success,and it is influenced by two factors:the late time discharge and the energy of the electric explosion.The longer time of the late time discharge and the more energy of the electric explosion,the easier it is to expand the HTD,which improves the probability of the ignition success.展开更多
目的探讨基于多期相动态对比增强磁共振(dynamic contrast-enhanced magnetic resonance imaging,DCE-MRI)影像组学在预测浸润性乳腺癌前哨淋巴结(sentinel lymph node,SLN)转移中的价值。方法回顾性收集2018年11月至2021年9月在济宁市...目的探讨基于多期相动态对比增强磁共振(dynamic contrast-enhanced magnetic resonance imaging,DCE-MRI)影像组学在预测浸润性乳腺癌前哨淋巴结(sentinel lymph node,SLN)转移中的价值。方法回顾性收集2018年11月至2021年9月在济宁市第一人民医院术前接受乳腺DCE-MRI检查且经病理证实的150名浸润性乳腺癌患者的临床、病理及MRI资料,其中,SLN转移阳性者61名,阴性者89名,并将其以8∶2的比例随机划分为训练集(n=120)与测试集(n=30)。在乳腺DCE-MRI(增强早期、增强峰值期及增强末期)剪影图像上进行手动逐层勾画感兴趣区(region of interest,ROI),获得三维容积感兴趣区域(volume of interest,VOI),再对各期进行提取影像组学特征,使用Z分数(Z-Score)归一化对特征进行归一化处理,然后再使用Select K Best和最小绝对收缩与选择算法(least absolute shrinkage and selection operator,LASSO)筛选出最优特征,并构建logistic回归(logistic regression,LR)模型。绘制受试者工作特征(receiver operating characteristic,ROC)曲线及曲线下面积(area under the curve,AUC)。运用ROC曲线与决策曲线分析(decision curve analysis,DCA)对模型进行评价。结果分别从增强早期、增强峰值期、增强末期及三期联合期相的图像中得到了10、10、10及11个最优特征,通过LR共构建4个预测模型。在训练集中,4个模型的AUC值分别为0.859、0.801、0.768、0.834。在测试集中,4个模型AUC值分别为0.843、0.806、0.806、0.866。DCA显示联合期相模型表现出了较高的净收益。结论DCE-MRI增强早期、增强峰值期及增强末期影像组学模型在预测浸润性乳腺癌SLN转移中均具有较好的预测效能,且测试集中联合期相的效能略高于单独期相。展开更多
目的分析基于健康行为改变整合理论(ITHBC)的健康教育在妊娠期糖尿病(GDM)中的应用效果。方法选取2019年5月至2021年5月我院收治的86例GDM患者,根据电脑盲选法将其分为对照组(n=43,常规护理)与研究组(n=43,常规护理+基于ITHBC的健康教育...目的分析基于健康行为改变整合理论(ITHBC)的健康教育在妊娠期糖尿病(GDM)中的应用效果。方法选取2019年5月至2021年5月我院收治的86例GDM患者,根据电脑盲选法将其分为对照组(n=43,常规护理)与研究组(n=43,常规护理+基于ITHBC的健康教育)。比较两组的干预效果。结果干预1个月后,研究组的空腹血糖(FBG)、餐后2 h血糖(2 h PG)、同型半胱氨酸(Hcy)及胱抑素C(CysC)水平均低于对照组(P<0.05)。干预1个月后,研究组的脂联素水平高于对照组,内脂素、瘦素水平低于对照组(P<0.05)。干预1个月后,研究组的饮食控制、主动运动、自我血糖监测及足部护理评分均高于对照组(P<0.05)。研究组的胎盘早剥、羊水过多、产后出血及新生儿窒息发生率均低于对照组(P<0.05)。结论基于ITHBC的健康教育用于GDM患者中的护理效果良好。展开更多
文摘Exploding foil initiator(EFI)is a kind of advanced device for initiating explosives,but its function is unstable when it comes to directly igniting pyrotechnics.To solve the problem,this research aims to reveal the ignition mechanism of EFIs directly igniting pyrotechnics.An oscilloscope,a photon Doppler velocimetry,and a plasma spectrum measurement system were employed to obtain information of electric characteristics,impact pressure,and plasma temperature.The results of the electric characteristics and the impact pressure were inconsistent with ignition results.The only thing that the ignition success tests had in common was that their plasma all had a relatively long period of high-temperature duration(HTD).It eventually concludes that the ignition mechanism in this research is the microconvection heat transfer rather than the shock initiation,which differs from that of exploding foil initiators detonating explosives.Furthermore,the methods for evaluating the ignition success of semiconductor bridge initiators are not entirely applicable to the tests mentioned in this paper.The HTD is the critical parameter for judging the ignition success,and it is influenced by two factors:the late time discharge and the energy of the electric explosion.The longer time of the late time discharge and the more energy of the electric explosion,the easier it is to expand the HTD,which improves the probability of the ignition success.
文摘目的探讨基于多期相动态对比增强磁共振(dynamic contrast-enhanced magnetic resonance imaging,DCE-MRI)影像组学在预测浸润性乳腺癌前哨淋巴结(sentinel lymph node,SLN)转移中的价值。方法回顾性收集2018年11月至2021年9月在济宁市第一人民医院术前接受乳腺DCE-MRI检查且经病理证实的150名浸润性乳腺癌患者的临床、病理及MRI资料,其中,SLN转移阳性者61名,阴性者89名,并将其以8∶2的比例随机划分为训练集(n=120)与测试集(n=30)。在乳腺DCE-MRI(增强早期、增强峰值期及增强末期)剪影图像上进行手动逐层勾画感兴趣区(region of interest,ROI),获得三维容积感兴趣区域(volume of interest,VOI),再对各期进行提取影像组学特征,使用Z分数(Z-Score)归一化对特征进行归一化处理,然后再使用Select K Best和最小绝对收缩与选择算法(least absolute shrinkage and selection operator,LASSO)筛选出最优特征,并构建logistic回归(logistic regression,LR)模型。绘制受试者工作特征(receiver operating characteristic,ROC)曲线及曲线下面积(area under the curve,AUC)。运用ROC曲线与决策曲线分析(decision curve analysis,DCA)对模型进行评价。结果分别从增强早期、增强峰值期、增强末期及三期联合期相的图像中得到了10、10、10及11个最优特征,通过LR共构建4个预测模型。在训练集中,4个模型的AUC值分别为0.859、0.801、0.768、0.834。在测试集中,4个模型AUC值分别为0.843、0.806、0.806、0.866。DCA显示联合期相模型表现出了较高的净收益。结论DCE-MRI增强早期、增强峰值期及增强末期影像组学模型在预测浸润性乳腺癌SLN转移中均具有较好的预测效能,且测试集中联合期相的效能略高于单独期相。
文摘目的分析基于健康行为改变整合理论(ITHBC)的健康教育在妊娠期糖尿病(GDM)中的应用效果。方法选取2019年5月至2021年5月我院收治的86例GDM患者,根据电脑盲选法将其分为对照组(n=43,常规护理)与研究组(n=43,常规护理+基于ITHBC的健康教育)。比较两组的干预效果。结果干预1个月后,研究组的空腹血糖(FBG)、餐后2 h血糖(2 h PG)、同型半胱氨酸(Hcy)及胱抑素C(CysC)水平均低于对照组(P<0.05)。干预1个月后,研究组的脂联素水平高于对照组,内脂素、瘦素水平低于对照组(P<0.05)。干预1个月后,研究组的饮食控制、主动运动、自我血糖监测及足部护理评分均高于对照组(P<0.05)。研究组的胎盘早剥、羊水过多、产后出血及新生儿窒息发生率均低于对照组(P<0.05)。结论基于ITHBC的健康教育用于GDM患者中的护理效果良好。
