The force model during needle insertion into soft tissue is important for accurate percutaneous intervention.In this paper,a force model for needle insertion into a tissue- equivalent material is presented and a serie...The force model during needle insertion into soft tissue is important for accurate percutaneous intervention.In this paper,a force model for needle insertion into a tissue- equivalent material is presented and a series of experiments are conducted to acquire data from needle soft- tissue interaction process.In order to build a more accurate insertion force model,the interaction force between a surgical needle and soft tissue is divided into three parts:stiffness force,friction force,and cutting force.The stiffness force is modeled on the basis of contact mechanics model.The friction force model is presented using a modified Winkler' s foundation model.The cutting force is viewed as a constant depending on a given tissue.The proposed models in the paper are established on the basis of the mechanical properties and geometric parameters of the needle and soft tissue.The experimental results illustrate that the force models are capable of predicting the needle-tissue interaction force.The force models of needle insertion can provide real-time haptic feedback for robot-assisted procedures,thereby improving the accuracy and safety of surgery.展开更多
Objective: To explore the analgesic effects and uterine hemodynamics of perpendicular needling(PN)and transverse needling(TN) at SP 6 in patients with primary dysmenorrhea(PD).Methods: In this randomized controlled tr...Objective: To explore the analgesic effects and uterine hemodynamics of perpendicular needling(PN)and transverse needling(TN) at SP 6 in patients with primary dysmenorrhea(PD).Methods: In this randomized controlled trial, patients with PD diagnosed with cold-dampness congealing pattern were randomly assigned in a ratio of 1:1 to receive PN or TN at bilateral SP 6 for 10 min.Acupuncture was performed when the menstrual pain score was over 40 mm on the first day of menstruation, as measured using the visual analog scale for pain(VAS-P). The primary outcome was average menstrual pain(VAS-P). Secondary outcomes included the pulsatility index(PI), resistance index(RI), and systolic-diastolic peaks ratio(S/D) in uterine arteries as measured using color Doppler ultrasonography;anxiety as assessed using the Hamilton Anxiety Rating Scale(HAMA), blood pressure(BP),and heart rate(HR).Results: Forty-eight patients completed the study. The TN group exhibited a significant reduction in VAS-P scores(-5.71 mm, 95% confidence interval(CI): -8.78, -2.63, P =.001), RI values(-0.05, 95% CI:-0.09, -0.01, P=.015), and HAMA values(-2.50, 95% CI: -4.78, -0.22, P=.032) when compared with the PN group. No significant differences in PI, S/D, BP, or HR values were observed between the two groups(P >.05).Conclusion: TN at SP 6 was superior to PN in alleviating menstrual pain and anxiety in patients with PD.This analgesic effect of TN may be due to its better ability to improve uterine arterial blood flow via decreases in RI values.展开更多
基金Supported by the National Natural Science Foundation of China(No.51175373)New Century Educational Talents Plan of Chinese Education Ministry(No.NCET-10-0625)+1 种基金Key Technology and Development Program of Tianjin Municipal Science and Technology Commission(No.12ZCDZSY10600)Tianjin Key Laboratory of High Speed Cutting&Precision Machining(TUTE)(2013120024001167)
文摘The force model during needle insertion into soft tissue is important for accurate percutaneous intervention.In this paper,a force model for needle insertion into a tissue- equivalent material is presented and a series of experiments are conducted to acquire data from needle soft- tissue interaction process.In order to build a more accurate insertion force model,the interaction force between a surgical needle and soft tissue is divided into three parts:stiffness force,friction force,and cutting force.The stiffness force is modeled on the basis of contact mechanics model.The friction force model is presented using a modified Winkler' s foundation model.The cutting force is viewed as a constant depending on a given tissue.The proposed models in the paper are established on the basis of the mechanical properties and geometric parameters of the needle and soft tissue.The experimental results illustrate that the force models are capable of predicting the needle-tissue interaction force.The force models of needle insertion can provide real-time haptic feedback for robot-assisted procedures,thereby improving the accuracy and safety of surgery.
基金funded by the Longitudinal Research Project of BUCM (2018-ZXFZJJ-010)。
文摘Objective: To explore the analgesic effects and uterine hemodynamics of perpendicular needling(PN)and transverse needling(TN) at SP 6 in patients with primary dysmenorrhea(PD).Methods: In this randomized controlled trial, patients with PD diagnosed with cold-dampness congealing pattern were randomly assigned in a ratio of 1:1 to receive PN or TN at bilateral SP 6 for 10 min.Acupuncture was performed when the menstrual pain score was over 40 mm on the first day of menstruation, as measured using the visual analog scale for pain(VAS-P). The primary outcome was average menstrual pain(VAS-P). Secondary outcomes included the pulsatility index(PI), resistance index(RI), and systolic-diastolic peaks ratio(S/D) in uterine arteries as measured using color Doppler ultrasonography;anxiety as assessed using the Hamilton Anxiety Rating Scale(HAMA), blood pressure(BP),and heart rate(HR).Results: Forty-eight patients completed the study. The TN group exhibited a significant reduction in VAS-P scores(-5.71 mm, 95% confidence interval(CI): -8.78, -2.63, P =.001), RI values(-0.05, 95% CI:-0.09, -0.01, P=.015), and HAMA values(-2.50, 95% CI: -4.78, -0.22, P=.032) when compared with the PN group. No significant differences in PI, S/D, BP, or HR values were observed between the two groups(P >.05).Conclusion: TN at SP 6 was superior to PN in alleviating menstrual pain and anxiety in patients with PD.This analgesic effect of TN may be due to its better ability to improve uterine arterial blood flow via decreases in RI values.
文摘为了研发适用严苛高温工业条件下使用的袋式除尘器用针刺毡滤袋,利用乳液浸渍后处理工艺制备了具有热电/压电特性的硅酸盐(Polar Silicate,PS)粉体/聚四氟乙烯(Polytetrafluoroethylene,PTFE)涂层复合芳纶针刺毡滤袋,探究了PS粉体粒径及附着浓度对复合滤袋捕集效率及阻力特性的影响规律,研究了复合滤袋机械性能,并通过扫描电镜(Scanning Electron Microscope,SEM)对复合滤袋进行了微观形貌分析。结果显示:PS粉体粒径对滤袋的阻力影响不大;PS粉体粒径在>21~32μm时,滤袋的过滤效率最大;最优附着浓度为6 mg/cm^(2)时,滤袋对0.3~1μm粒子的过滤效率提升幅度≥12.58百分点,滤袋的品质因数最高;PS粉体/PTFE/芳纶复合滤袋的耐磨性比芳纶针刺毡滤袋提升了19.86%,挺度提升了22.22%,纵向拉伸强度提升了14.07%。研究所制备的复合滤袋能够适应严苛的高温工业环境,可更好地控制工业排放的微细颗粒物。
