AIM: To compare the diagnostic accuracy of pelvic phased-array magnetic resonance imaging (MRI) and endorectal ultrasonography (ERUS) in the preoperative staging of rectal carcinoma. METHODS: Thirty-four patients (15 ...AIM: To compare the diagnostic accuracy of pelvic phased-array magnetic resonance imaging (MRI) and endorectal ultrasonography (ERUS) in the preoperative staging of rectal carcinoma. METHODS: Thirty-four patients (15 males, 19 females) with ages ranging between 29 and 75 who have biopsy proven rectal tumor underwent both MRI and ERUS examinations before surgery. All patients were evaluated to determine the diagnostic accuracy of depth of transmural tumor invasion and lymph node metastases. Imaging results were correlated with histopathological findings regarded as the gold standard and both modalities were compared in terms of predicting preoperative local staging of rectal carcinoma. RESULTS: The pathological T stage of the tumors was: pT1 in 1 patient, pT2 in 9 patients, pT3 in 21 patients and pT4 in 3 patients. The pathological N stage of the tumors was: pN0 in 19 patients, pN1 in 9 patients and pN2 in 6 patients. The accuracy of T staging for MRI was 89.70% (27 out of 34). The sensitivity was 79.41% and the specificity was 93.14%. The accuracy of T staging for ERUS was 85.29% (24 out of 34). The sensitivity was 70.59% and the specificity was 90.20%. Detection of lymph node metastases usingphased-array MRI gave an accuracy of 74.50% (21 out of 34). The sensitivity and specificity was found to be 61.76% and 80.88%, respectively. By using ERUS in the detection of lymph node metastases, an accuracy of 76.47% (18 out of 34) was obtained. The sensitivity and specificity were found to be 52.94% and 84.31%, respectively. CONCLUSION: ERUS and phased-array MRI are complementary methods in the accurate preoperative staging of rectal cancer. In conclusion, we can state that phased-array MRI was observed to be slightly superior in determining the depth of transmural invasion (T stage) and has same value in detecting lymph node metastases (N stage) as compared to ERUS.展开更多
目的实现并改善经颅磁刺激(transcranial magnetic stimulation,TMS)的磁聚焦特性。方法构建8个线圈和20个线圈的圆环面线圈阵列模型,结合改进的粒子群算法设计了自适应混合遗传算法,对影响线圈阵列模型磁聚焦性的各种参数进行优化求解...目的实现并改善经颅磁刺激(transcranial magnetic stimulation,TMS)的磁聚焦特性。方法构建8个线圈和20个线圈的圆环面线圈阵列模型,结合改进的粒子群算法设计了自适应混合遗传算法,对影响线圈阵列模型磁聚焦性的各种参数进行优化求解。结果在不同平面产生的磁场优化表明了改进的优化算法具有很好的全局搜索与局部搜索能力,在算法的优化下,显示了线圈阵列在优化电流组态下在计算区域内的归一化幅值分布和二维等高线图。结论两种线圈阵列模型在平面上产生了明显的聚焦区域,在目标区域内产生了具有良好磁聚焦性能的磁场分布;在深度方向上有较好的聚焦性能,磁场变化梯度大,更有利于磁刺激兴奋位定点;并且20个子线圈的线圈模型基本上实现了点聚焦,同时具有可聚焦多个靶目标的能力。展开更多
In human-machine interaction,robotic hands are useful in many scenarios.To operate robotic hands via gestures instead of handles will greatly improve the convenience and intuition of human-machine interaction.Here,we ...In human-machine interaction,robotic hands are useful in many scenarios.To operate robotic hands via gestures instead of handles will greatly improve the convenience and intuition of human-machine interaction.Here,we present a magnetic array assisted sliding triboelectric sensor for achieving a real-time gesture interaction between a human hand and robotic hand.With a finger’s traction movement of flexion or extension,the sensor can induce positive/negative pulse signals.Through counting the pulses in unit time,the degree,speed,and direction of finger motion can be judged in realtime.The magnetic array plays an important role in generating the quantifiable pulses.The designed two parts of magnetic array can transform sliding motion into contact-separation and constrain the sliding pathway,respectively,thus improve the durability,low speed signal amplitude,and stability of the system.This direct quantization approach and optimization of wearable gesture sensor provide a new strategy for achieving a natural,intuitive,and real-time human-robotic interaction.展开更多
基于多台海洋磁力仪、测深仪和GPS,研制了数据合成器、水下拖体、电源适配器、数据收录兼导航软件,最终构建了一种阵列式海洋磁力测量系统。该阵列式海洋磁力测量系统具备3个磁力仪通道,动态噪声≤0.3n T p-p,采样率为10Hz,水下部分总...基于多台海洋磁力仪、测深仪和GPS,研制了数据合成器、水下拖体、电源适配器、数据收录兼导航软件,最终构建了一种阵列式海洋磁力测量系统。该阵列式海洋磁力测量系统具备3个磁力仪通道,动态噪声≤0.3n T p-p,采样率为10Hz,水下部分总重量≤95kg,配迫降翼后入水深度可达22m。该阵列式磁力测量系统曾被应用于董家口港区某锚地的未爆炸物探测,最终确定了多个疑似物位置。展开更多
文摘AIM: To compare the diagnostic accuracy of pelvic phased-array magnetic resonance imaging (MRI) and endorectal ultrasonography (ERUS) in the preoperative staging of rectal carcinoma. METHODS: Thirty-four patients (15 males, 19 females) with ages ranging between 29 and 75 who have biopsy proven rectal tumor underwent both MRI and ERUS examinations before surgery. All patients were evaluated to determine the diagnostic accuracy of depth of transmural tumor invasion and lymph node metastases. Imaging results were correlated with histopathological findings regarded as the gold standard and both modalities were compared in terms of predicting preoperative local staging of rectal carcinoma. RESULTS: The pathological T stage of the tumors was: pT1 in 1 patient, pT2 in 9 patients, pT3 in 21 patients and pT4 in 3 patients. The pathological N stage of the tumors was: pN0 in 19 patients, pN1 in 9 patients and pN2 in 6 patients. The accuracy of T staging for MRI was 89.70% (27 out of 34). The sensitivity was 79.41% and the specificity was 93.14%. The accuracy of T staging for ERUS was 85.29% (24 out of 34). The sensitivity was 70.59% and the specificity was 90.20%. Detection of lymph node metastases usingphased-array MRI gave an accuracy of 74.50% (21 out of 34). The sensitivity and specificity was found to be 61.76% and 80.88%, respectively. By using ERUS in the detection of lymph node metastases, an accuracy of 76.47% (18 out of 34) was obtained. The sensitivity and specificity were found to be 52.94% and 84.31%, respectively. CONCLUSION: ERUS and phased-array MRI are complementary methods in the accurate preoperative staging of rectal cancer. In conclusion, we can state that phased-array MRI was observed to be slightly superior in determining the depth of transmural invasion (T stage) and has same value in detecting lymph node metastases (N stage) as compared to ERUS.
文摘目的实现并改善经颅磁刺激(transcranial magnetic stimulation,TMS)的磁聚焦特性。方法构建8个线圈和20个线圈的圆环面线圈阵列模型,结合改进的粒子群算法设计了自适应混合遗传算法,对影响线圈阵列模型磁聚焦性的各种参数进行优化求解。结果在不同平面产生的磁场优化表明了改进的优化算法具有很好的全局搜索与局部搜索能力,在算法的优化下,显示了线圈阵列在优化电流组态下在计算区域内的归一化幅值分布和二维等高线图。结论两种线圈阵列模型在平面上产生了明显的聚焦区域,在目标区域内产生了具有良好磁聚焦性能的磁场分布;在深度方向上有较好的聚焦性能,磁场变化梯度大,更有利于磁刺激兴奋位定点;并且20个子线圈的线圈模型基本上实现了点聚焦,同时具有可聚焦多个靶目标的能力。
基金This work was supported by National Natural Science Foundation of China(51902035 and 52073037)Natural Science Foundation of Chongqing(cstc2020jcyj-msxmX0807)+1 种基金the Fundamental Research Funds for the Central Universities(2020CDJ-LHSS-001 and 2019CDXZWL001)Chongqing graduate tutor team construction project(ydstd1832).
文摘In human-machine interaction,robotic hands are useful in many scenarios.To operate robotic hands via gestures instead of handles will greatly improve the convenience and intuition of human-machine interaction.Here,we present a magnetic array assisted sliding triboelectric sensor for achieving a real-time gesture interaction between a human hand and robotic hand.With a finger’s traction movement of flexion or extension,the sensor can induce positive/negative pulse signals.Through counting the pulses in unit time,the degree,speed,and direction of finger motion can be judged in realtime.The magnetic array plays an important role in generating the quantifiable pulses.The designed two parts of magnetic array can transform sliding motion into contact-separation and constrain the sliding pathway,respectively,thus improve the durability,low speed signal amplitude,and stability of the system.This direct quantization approach and optimization of wearable gesture sensor provide a new strategy for achieving a natural,intuitive,and real-time human-robotic interaction.
文摘基于多台海洋磁力仪、测深仪和GPS,研制了数据合成器、水下拖体、电源适配器、数据收录兼导航软件,最终构建了一种阵列式海洋磁力测量系统。该阵列式海洋磁力测量系统具备3个磁力仪通道,动态噪声≤0.3n T p-p,采样率为10Hz,水下部分总重量≤95kg,配迫降翼后入水深度可达22m。该阵列式磁力测量系统曾被应用于董家口港区某锚地的未爆炸物探测,最终确定了多个疑似物位置。
