Objective To investigate the spike activities of cerebellar cortical cells in a computational network model con- structed based on the anatomical structure of cerebellar cortex. Methods and Results The multicompartmen...Objective To investigate the spike activities of cerebellar cortical cells in a computational network model con- structed based on the anatomical structure of cerebellar cortex. Methods and Results The multicompartment model of neuron and NEURON software were used to study the external influences on cerebellar cortical cells. Various potential spike patterns in these cells were obtained. By analyzing the impacts of different incoming stimuli on the potential spike of Purkinje cell, temporal focusing caused by the granule cell-golgi cell feedback inhibitory loop to Purkinje cell and spa- tial focusing caused by the parallel fiber-basket/stellate cell local inhibitory loop to Purkinje cell were discussed. Finally, the motor learning process of rabbit eye blink conditioned reflex was demonstrated in this model. The simulation results showed that when the afferent from climbing fiber existed, rabbit adaptation to eye blinking gradually became stable under the Spike Timing-Dependent Plasticity （STDP） learning rule. Conclusion The constructed cerebellar cortex network is a reliable and feasible model. The model simulation results confirmed the output signal stability of cerebellar cortex after STDP learning and the network can execute the function of spatial and temporal focusing.展开更多
As an example of our new approach to complex near-field （NF） scattering of electromagnetic waves, the timereversal （TR） transmission process on an NF current-element array is mapped to the statistical process on a...As an example of our new approach to complex near-field （NF） scattering of electromagnetic waves, the timereversal （TR） transmission process on an NF current-element array is mapped to the statistical process on a kinetic Ising transmission chain. Equilibrium statistical mechanics and non-equilibrium Monte Carlo （MC） dynamics help us to find signal jamming, aging, annihilating, creating, and TR symmetry breaking on the chain with inevitable background noises; and these results are general in NF systems where complex electromagnetic scattering arises.展开更多
Using the combination of a refective blazed grating and a reflective phase-only difractive spatiallight modulator(SLM),scanless multitarget-matching multiphoton excitation fuorescence mi.croscopy(SMTM-MP M)was achieve...Using the combination of a refective blazed grating and a reflective phase-only difractive spatiallight modulator(SLM),scanless multitarget-matching multiphoton excitation fuorescence mi.croscopy(SMTM-MP M)was achieved.The SLM shaped an incoming mode-locked,near-infraredTi:sapphire laser beam into an excitation pattern with addressable shapes and sizes that matchedthe samples of interest in the field of view.Temporal and spatial focusing were simultaneouslyrealized by combining an objective lens and a blazed grating.The fluorescence signal fromilluminated areas was recorded by a two-dimensional sCMOS camera.Compared with a conventional temporal focusing multiphoton microscope,our microscope achieved effective use of thelaser power and decreased photodamage with higher axial resolution.展开更多
Three-photon wide-field depth-resolved excitation is used to overcome some of the limitations in conventional point-scanning two-and three-photon microscopy.Excitation of chromophores as diverse as channelrhodopsins a...Three-photon wide-field depth-resolved excitation is used to overcome some of the limitations in conventional point-scanning two-and three-photon microscopy.Excitation of chromophores as diverse as channelrhodopsins and quantum dots is shown,and a penetration depth of more than 700μm into fixed scattering brain tissue is achieved,approximately twice as deep as that achieved using two-photon wide-field excitation.Compatibility with live animal experiments is confirmed by imaging the cerebral vasculature of an anesthetized mouse;a complete focal stack was obtained without any evidence of photodamage.As an additional validation of the utility of wide-field three-photon excitation,functional excitation is demonstrated by performing threephoton optogenetic stimulation of cultured mouse hippocampal neurons expressing a channelrhodopsin;action potentials could reliably be excited without causing photodamage.展开更多
基金supported by the grants from National Natural Science Foundation of China (No. 10872069)
文摘Objective To investigate the spike activities of cerebellar cortical cells in a computational network model con- structed based on the anatomical structure of cerebellar cortex. Methods and Results The multicompartment model of neuron and NEURON software were used to study the external influences on cerebellar cortical cells. Various potential spike patterns in these cells were obtained. By analyzing the impacts of different incoming stimuli on the potential spike of Purkinje cell, temporal focusing caused by the granule cell-golgi cell feedback inhibitory loop to Purkinje cell and spa- tial focusing caused by the parallel fiber-basket/stellate cell local inhibitory loop to Purkinje cell were discussed. Finally, the motor learning process of rabbit eye blink conditioned reflex was demonstrated in this model. The simulation results showed that when the afferent from climbing fiber existed, rabbit adaptation to eye blinking gradually became stable under the Spike Timing-Dependent Plasticity （STDP） learning rule. Conclusion The constructed cerebellar cortex network is a reliable and feasible model. The model simulation results confirmed the output signal stability of cerebellar cortex after STDP learning and the network can execute the function of spatial and temporal focusing.
基金supported by the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No.20100185110021)the National Natural Science Foundation of China (Grant No.61071031)
文摘As an example of our new approach to complex near-field （NF） scattering of electromagnetic waves, the timereversal （TR） transmission process on an NF current-element array is mapped to the statistical process on a kinetic Ising transmission chain. Equilibrium statistical mechanics and non-equilibrium Monte Carlo （MC） dynamics help us to find signal jamming, aging, annihilating, creating, and TR symmetry breaking on the chain with inevitable background noises; and these results are general in NF systems where complex electromagnetic scattering arises.
基金supported by Specially Funded Program on National Key Scienti¯c Instruments and Equipment Development(61527827),Program 973(2015CB352005)the National Natural Science Foundation of China(31171372/61525503/61378091/61620106016),Guangdong Natural Science Foundation(2014A030312008/2015A020214023/2015KGJHZ002)Shenzhen Science and Technology R&D Foundation(JCYJ20160422151611496).
文摘Using the combination of a refective blazed grating and a reflective phase-only difractive spatiallight modulator(SLM),scanless multitarget-matching multiphoton excitation fuorescence mi.croscopy(SMTM-MP M)was achieved.The SLM shaped an incoming mode-locked,near-infraredTi:sapphire laser beam into an excitation pattern with addressable shapes and sizes that matchedthe samples of interest in the field of view.Temporal and spatial focusing were simultaneouslyrealized by combining an objective lens and a blazed grating.The fluorescence signal fromilluminated areas was recorded by a two-dimensional sCMOS camera.Compared with a conventional temporal focusing multiphoton microscope,our microscope achieved effective use of thelaser power and decreased photodamage with higher axial resolution.
基金support from NIH-5-P41-EB015871-27,DP3-DK10102401,1-U01-NS090438-01,1-R01-EY017656-0,6A1,1-R01-HL121386-01A1the Biosym IRG of Singapore-MIT Alliance Research and Technology Center+6 种基金the Koch Institute for Integrative Cancer Research Bridge Initiativethe Hamamatsu Inc.,and the Samsung GRO programsupported by the Wellcome Trust 093831/Z/10/Zfunding from NIH 1R24MH106075,NIH 2R01DA029639,NIH 1R01MH103910,NIH 1R01GM104948,the MIT Media Lab,the New York Stem Cell Foundation-Robertson Award and NSF CBET 1053233an EMBO Longterm Fellowship to carry out this researchsupport from NIH 5U54 CA151884-04 and 9-P41-EB015871-26A1for NCI grants R35 CA197743 and P01 CA080124 to carry out this work.
文摘Three-photon wide-field depth-resolved excitation is used to overcome some of the limitations in conventional point-scanning two-and three-photon microscopy.Excitation of chromophores as diverse as channelrhodopsins and quantum dots is shown,and a penetration depth of more than 700μm into fixed scattering brain tissue is achieved,approximately twice as deep as that achieved using two-photon wide-field excitation.Compatibility with live animal experiments is confirmed by imaging the cerebral vasculature of an anesthetized mouse;a complete focal stack was obtained without any evidence of photodamage.As an additional validation of the utility of wide-field three-photon excitation,functional excitation is demonstrated by performing threephoton optogenetic stimulation of cultured mouse hippocampal neurons expressing a channelrhodopsin;action potentials could reliably be excited without causing photodamage.
