The principle of optical trapping is conventionally based on the interaction of optical fields with linear-induced polarizations. However, the optical force originating from the nonlinear polarization becomes signific...The principle of optical trapping is conventionally based on the interaction of optical fields with linear-induced polarizations. However, the optical force originating from the nonlinear polarization becomes significant when nonlinear optical nanoparticles are trapped by femtosecond laser pulses. Herein we develop the time-averaged optical forces on a nonlinear optical nanoparticle using high-repetition-rate femtosecond laser pulses, based on the linear and nonlinear polarization effects. We investigate the dependence of the optical forces on the magnitudes and signs of the refractive nonlinearities. It is found that the self-focusing effect enhances the trapping ability, whereas the self-defocusing effect leads to the splitting of the potential well at the focal plane and destabilizes the optical trap. Our results show good agreement with the reported experimental observations and provide theoretical support for capturing nonlinear optical particles.展开更多
OBJECTIVE:To study the effect of acupuncture at Fengchi(GB 20) on the activation of myosin light chain kinase(MLCK) in the middle meningeal artery of migraine modeled rats.METHODS:Forty-four clean grade healthy female...OBJECTIVE:To study the effect of acupuncture at Fengchi(GB 20) on the activation of myosin light chain kinase(MLCK) in the middle meningeal artery of migraine modeled rats.METHODS:Forty-four clean grade healthy female Sprague-Dawley(SD) rats were randomly divided into four groups:the control group,blank control group,Fengchi(GB 20) acupuncture group,and Fengchi(GB 20) prevention group.Neurogenic inflammation of these rats was induced by electrical stimulation.The γ-^(32)P infiltration method was then used to detect MLCK activation in the middle meningeal artery,and immunocytochemistry was applied to detect the structural protein expression of MLCK.RESULTS:The migraine model was successfully established in the rats.Compared with the control group,MLCK activation was significantly decreased in the blank control group(P < 0.01).CONCLUSION:The activation of MLCK in the middle meningeal artery was increased by acupuncture at Fengchi(GB 20),indicating its effectiveness in preventing and curing on acute migraine attacks.展开更多
基金National Natural Science Foundation of China(NSFC)(11474052,11504049,11774055,61535003)Natural Science Foundation of Jiangsu Province,China(BK20171364)National Key Basic Research Program of China(2015CB352002)
文摘The principle of optical trapping is conventionally based on the interaction of optical fields with linear-induced polarizations. However, the optical force originating from the nonlinear polarization becomes significant when nonlinear optical nanoparticles are trapped by femtosecond laser pulses. Herein we develop the time-averaged optical forces on a nonlinear optical nanoparticle using high-repetition-rate femtosecond laser pulses, based on the linear and nonlinear polarization effects. We investigate the dependence of the optical forces on the magnitudes and signs of the refractive nonlinearities. It is found that the self-focusing effect enhances the trapping ability, whereas the self-defocusing effect leads to the splitting of the potential well at the focal plane and destabilizes the optical trap. Our results show good agreement with the reported experimental observations and provide theoretical support for capturing nonlinear optical particles.
基金the Beijing Natural Science Found Program[Fengchi point(GB 20)Controlling Mechanisn of MLCK Signal System of the Migraine,No.7092054
文摘OBJECTIVE:To study the effect of acupuncture at Fengchi(GB 20) on the activation of myosin light chain kinase(MLCK) in the middle meningeal artery of migraine modeled rats.METHODS:Forty-four clean grade healthy female Sprague-Dawley(SD) rats were randomly divided into four groups:the control group,blank control group,Fengchi(GB 20) acupuncture group,and Fengchi(GB 20) prevention group.Neurogenic inflammation of these rats was induced by electrical stimulation.The γ-^(32)P infiltration method was then used to detect MLCK activation in the middle meningeal artery,and immunocytochemistry was applied to detect the structural protein expression of MLCK.RESULTS:The migraine model was successfully established in the rats.Compared with the control group,MLCK activation was significantly decreased in the blank control group(P < 0.01).CONCLUSION:The activation of MLCK in the middle meningeal artery was increased by acupuncture at Fengchi(GB 20),indicating its effectiveness in preventing and curing on acute migraine attacks.