Fear extinction is a biological process in which learned fear behavior diminishes without anticipated reinforcement,allowing the organism to re-adapt to ever-changing situations.Based on the behavioral hypothesis that...Fear extinction is a biological process in which learned fear behavior diminishes without anticipated reinforcement,allowing the organism to re-adapt to ever-changing situations.Based on the behavioral hypothesis that extinction is new learning and forms an extinction memory,this new memory is more readily forgettable than the original fear memory.The brain’s cellular and synaptic traces underpinning this inherently fragile yet reinforceable extinction memory remain unclear.Intriguing questions are about the whereabouts of the engram neurons that emerged during extinction learning and how they constitute a dynamically evolving functional construct that works in concert to store and express the extinction memory.In this review,we discuss recent advances in the engram circuits and their neural connectivity plasticity for fear extinction,aiming to establish a conceptual framework for understanding the dynamic competition between fear and extinction memories in adaptive control of conditioned fear responses.展开更多
A full automatic welding machine for spherical tanks' all position multi layer welds has been developed. This machine is mainly composed of a two dimension seam tracking system based on microcomputer's memor...A full automatic welding machine for spherical tanks' all position multi layer welds has been developed. This machine is mainly composed of a two dimension seam tracking system based on microcomputer's memory and a welding tractor as well as rail. The main features of the machine are: while welding the first layer of a seam, its microcomputer system can analyze and store the tracing information from a two dimension sensor, and control the welding head device to realize two dimension real time tracing; while welding the second layer up to the top layer of the seam, it can realize two dimension tracing based on the memorial data, automatically determine the layer number and continually sway the welding head. The welding test shows that the machine has good tracing and welding behavior, and is suitable for spherical tank's all position multi layer welds.展开更多
Artificial photonic synapses have set off a new upsurge for mimicking a series of neural activities in recent years.In particular,the investigation of learning and memory behaviors with pressure or emotion and corresp...Artificial photonic synapses have set off a new upsurge for mimicking a series of neural activities in recent years.In particular,the investigation of learning and memory behaviors with pressure or emotion and corresponding mechanisms is currently the focus of more attention.Herein,a hippocampus-inspired device based on MoS_(2) for illumination time encoding is fabricated,in which the encryption technology is employed for data security.In addition,the pressureinduced memory behaviors with full memory function(memory trace)over time such as encoding,storage and retrieval are demonstrated,resulting from the decreasing positive photocurrent of the MoS;devices.The proposed mechanism of the memory effect when exposed to the light is elucidated in detail.Moreover,the effect of stress hormone on memory behavior is displayed via different illumination time periods and light intensities.These results indicate the potential application of MoS_(2) devices in artificial neural network.展开更多
基金supported by grants from the STI2030-Major Projects(2021ZD0202800)the National Natural Science Foundation of China(32071023 and 32371078)+2 种基金the Program of Shanghai Academic/Technology Research Leader(22XD1420700)the Shanghai Municipal Health Commission(2022XD046)Innovative Research Team of High-Level Local Universities in Shanghai.
文摘Fear extinction is a biological process in which learned fear behavior diminishes without anticipated reinforcement,allowing the organism to re-adapt to ever-changing situations.Based on the behavioral hypothesis that extinction is new learning and forms an extinction memory,this new memory is more readily forgettable than the original fear memory.The brain’s cellular and synaptic traces underpinning this inherently fragile yet reinforceable extinction memory remain unclear.Intriguing questions are about the whereabouts of the engram neurons that emerged during extinction learning and how they constitute a dynamically evolving functional construct that works in concert to store and express the extinction memory.In this review,we discuss recent advances in the engram circuits and their neural connectivity plasticity for fear extinction,aiming to establish a conceptual framework for understanding the dynamic competition between fear and extinction memories in adaptive control of conditioned fear responses.
文摘A full automatic welding machine for spherical tanks' all position multi layer welds has been developed. This machine is mainly composed of a two dimension seam tracking system based on microcomputer's memory and a welding tractor as well as rail. The main features of the machine are: while welding the first layer of a seam, its microcomputer system can analyze and store the tracing information from a two dimension sensor, and control the welding head device to realize two dimension real time tracing; while welding the second layer up to the top layer of the seam, it can realize two dimension tracing based on the memorial data, automatically determine the layer number and continually sway the welding head. The welding test shows that the machine has good tracing and welding behavior, and is suitable for spherical tank's all position multi layer welds.
基金supported by the Innovation Group Project of Sichuan Province(20CXTD0090)the Fundamental Research Funds for the Central Universities(ZYGX2019Z018)+4 种基金the University of Electronic Science and Technology of China(UESTC)Shared Research Facilities of Electromagnetic Wave and Matter Interaction(Y0301901290100201)the National Natural Science Foundation of China(62004025)the International Postdoctoral Exchange Fellowship Program(Talent-Introduction Program,244125)the UESTC 100-Talent Project FundChina Postdoctoral Science Foundation(244125)。
文摘Artificial photonic synapses have set off a new upsurge for mimicking a series of neural activities in recent years.In particular,the investigation of learning and memory behaviors with pressure or emotion and corresponding mechanisms is currently the focus of more attention.Herein,a hippocampus-inspired device based on MoS_(2) for illumination time encoding is fabricated,in which the encryption technology is employed for data security.In addition,the pressureinduced memory behaviors with full memory function(memory trace)over time such as encoding,storage and retrieval are demonstrated,resulting from the decreasing positive photocurrent of the MoS;devices.The proposed mechanism of the memory effect when exposed to the light is elucidated in detail.Moreover,the effect of stress hormone on memory behavior is displayed via different illumination time periods and light intensities.These results indicate the potential application of MoS_(2) devices in artificial neural network.
