目的:先前的研究已经证明丘脑-皮层网络在全身麻醉药诱导意识消失过程中起着至关重要的作用。依托咪酯广泛用于临床麻醉,可以可逆性地引起意识消失(loss of consciousness,LOC)。我们的前期研究表明依托咪酯增强丘脑皮层网络γ-氨基丁酸...目的:先前的研究已经证明丘脑-皮层网络在全身麻醉药诱导意识消失过程中起着至关重要的作用。依托咪酯广泛用于临床麻醉,可以可逆性地引起意识消失(loss of consciousness,LOC)。我们的前期研究表明依托咪酯增强丘脑皮层网络γ-氨基丁酸(GABA)和谷氨酸能神经传递。然而,依托咪酯对丘脑皮层网络神经元动作电位的影响尚不清楚。本研究拟借助膜片钳技术观察依托咪酯对丘脑皮层网络神经元动作电位的影响。方法:20只健康(10~20d)雄性SD大鼠制备含丘脑腹后内侧核(VPM)和初级躯体感觉桶状皮层(S1BF)的丘脑皮层离体脑片。运用全细胞膜片钳,观察不同浓度依托咪酯(3.0μmol/L,6.0μmol/L和12.0μmol/L)对大鼠离体脑片丘脑皮层网络动作电位超摄值(OS)、升高其阈值(TP)和90%复极化动作电位时程(APD90)的影响。结果:依托咪酯降低丘脑VPM和S1BF动作电位的OS值,升高其TP,延长APD90。依托咪酯还降低了这两个脑区神经元动作电位的发放频率。与S1BF比较,依托咪酯对丘脑VPM神经元的抑制程度更大。结论:依托咪酯抑制丘脑-皮层神经元动作电位的产生,降低其发放频率,可能是其导致意识消失的机制之一。展开更多
Wind turbine employs pitch angle control to maintain captured power at its rated value when the wind speed is higher than rated value.This work adopts a perturbation observer based sliding-mode control(POSMC)strategy ...Wind turbine employs pitch angle control to maintain captured power at its rated value when the wind speed is higher than rated value.This work adopts a perturbation observer based sliding-mode control(POSMC)strategy to realize robust variable-pitch control of permanent magnet synchronous generator(PMSG).POSMC combines system nonlinearities,parametric uncertainties,unmodelled dynamics,and time-varying external disturbances into a perturbation,which aims to estimate the perturbation via a perturbation observer without an accurate system model.Subsequently,sliding mode control(SMC)is designed to completely compensate perturbation estimation in real-time for the sake of achieving a global consistent control performance and improving system robustness under complicated environments.Simulation results indicate that,compared with vector control(VC),feedback linearization control(FLC),and nonlinear adaptive control(NAC),POSMC has the best control performance in ramp wind and random wind and the highest robustness in terms of parameter uncertainty.Specially,the integral absolute error index of!m of POSMC is only 11.69%,12.10%and 15.14%of that of VC,FLC and NAC in random wind speed.展开更多
文摘目的:先前的研究已经证明丘脑-皮层网络在全身麻醉药诱导意识消失过程中起着至关重要的作用。依托咪酯广泛用于临床麻醉,可以可逆性地引起意识消失(loss of consciousness,LOC)。我们的前期研究表明依托咪酯增强丘脑皮层网络γ-氨基丁酸(GABA)和谷氨酸能神经传递。然而,依托咪酯对丘脑皮层网络神经元动作电位的影响尚不清楚。本研究拟借助膜片钳技术观察依托咪酯对丘脑皮层网络神经元动作电位的影响。方法:20只健康(10~20d)雄性SD大鼠制备含丘脑腹后内侧核(VPM)和初级躯体感觉桶状皮层(S1BF)的丘脑皮层离体脑片。运用全细胞膜片钳,观察不同浓度依托咪酯(3.0μmol/L,6.0μmol/L和12.0μmol/L)对大鼠离体脑片丘脑皮层网络动作电位超摄值(OS)、升高其阈值(TP)和90%复极化动作电位时程(APD90)的影响。结果:依托咪酯降低丘脑VPM和S1BF动作电位的OS值,升高其TP,延长APD90。依托咪酯还降低了这两个脑区神经元动作电位的发放频率。与S1BF比较,依托咪酯对丘脑VPM神经元的抑制程度更大。结论:依托咪酯抑制丘脑-皮层神经元动作电位的产生,降低其发放频率,可能是其导致意识消失的机制之一。
基金support of the Noise problem of electric vehicle brushless DC motor starting(S202010641109).
文摘Wind turbine employs pitch angle control to maintain captured power at its rated value when the wind speed is higher than rated value.This work adopts a perturbation observer based sliding-mode control(POSMC)strategy to realize robust variable-pitch control of permanent magnet synchronous generator(PMSG).POSMC combines system nonlinearities,parametric uncertainties,unmodelled dynamics,and time-varying external disturbances into a perturbation,which aims to estimate the perturbation via a perturbation observer without an accurate system model.Subsequently,sliding mode control(SMC)is designed to completely compensate perturbation estimation in real-time for the sake of achieving a global consistent control performance and improving system robustness under complicated environments.Simulation results indicate that,compared with vector control(VC),feedback linearization control(FLC),and nonlinear adaptive control(NAC),POSMC has the best control performance in ramp wind and random wind and the highest robustness in terms of parameter uncertainty.Specially,the integral absolute error index of!m of POSMC is only 11.69%,12.10%and 15.14%of that of VC,FLC and NAC in random wind speed.
