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Stochastic spin-orbit-torque device as the STDP synapse for spiking neural networks

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Science China(Physics,Mechanics & Astronomy) 2023年第5期66卷 188-194页

作者： Haotian li liyuan li Kaiyuan Zhou Chunjie Yan Zhenyu Gao Zishuang li Ronghua liu National Laboratory of Solid State Microstructures Jiangsu Provincial Key Laboratory for NanotechnologySchool of PhysicsNanjing UniversityNanjing 210093China

Neuromorphic hardware,as a non-Von Neumann architecture,has better energy efficiency and parallelism than the conventional ***,with the numerical modeling spin-orbit torque(SOT)device using current-induced SOT and Joule heating effects,we acquire its magnetization stochastic switching probability as a function of the interval time of input current pulses and use it to mimic the spike-timing-dependent plasticity learning behavior like actual brain *** further demonstrate that the artificial spiking neural network(SNN)built by this SOT device can perform unsupervised handwritten digit recognition with an accuracy of 80%and logic operation *** work provides a new clue to achieving SNN-based neuromorphic hardware using high-energy efficiency and nonvolatile spintronics nanodevices.

关键词： spin-orbit torque neuromorphic hardware spiking neural network stochastic magnetization reversal

Glutamatergic Neurons in the Caudal Zona Incerta Regulate Parkinsonian Motor Symptoms in Mice

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Neuroscience Bulletin 2022年第1期38卷 1-15页

作者： li-Xuan li Yu-Lan li Jin-Tao Wu Ji-Zhou Song Xiao-Ming li Department of Neurobiology and Department of Neurology of the Second Affiliated Hospital Zhejiang University School of MedicineHangzhou310003China NHC and CAMS Key Laboratory of Medical Neurobiology Ministry of Education Frontier Science Center for Brain Research and Brain-Machine IntegrationSchool of Brain Science and Brain MedicineZhejiang University School of MedicineHangzhou310030China Department of Engineering Mechanics Soft Matter Research Centerand Key Laboratory of Soft Machines and Smart Devices of Zhejiang ProvinceZhejiang UniversityHangzhou310063China

Parkinson’s disease(PD)is the second most common and fastest-growing neurodegenerative *** recent years,it has been recognized that neurotransmitters other than dopamine and neuronal systems outside the basal ganglia are also related to PD ***,little is known about whether and how the caudal zona incerta(ZIc)regulates parkinsonian motor ***,we showed that specific glutamatergic but not GABAergic ZIc^(VgluT2) neurons regulated these ***^(VgluT2) neuronal activation induced time-locked parkinsonian motor *** mouse models of PD,the ZIc^(VgluT2) neurons were hyperactive and inhibition of their activity ameliorated the motor ***^(VgluT2) neurons monosynaptically projected to the substantia nigra pars ***-nigral circuit activation induced parkinsonian motor ***,our findings provide a direct link between the ZIc,its glutamatergic neurons,and parkinsonian motor symptoms for the first time,help to better understand the mechanisms of PD,and supply a new important potential therapeutic target for PD.

关键词： Parkinson's disease Caudal zona incerta Glutamate Substantia nigra pars reticulata Parkinsonian motor symptoms

Exact Periodic and Solitary-Wave Solutions of Multi-component Modified Korteweg-de Vries Equations

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Communications in Theoretical Physics 2009年第4期51卷 588-594页

作者： ZHANG Huan TIAN Bo ZHANG Hai-Qiang li li-li School of Science P.O. Box 122 Beijing University of Posts and Telecommunications Beijing 100876 China State Key Laboratory of Software Development Environment Beijing University of Aeronautics and Astronautics Beijing 100083 China Key Laboratory of Optical Communication and lightwave Technologies Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

The present work extends the search of Jacobi elliptic function solutions for the multi-component modified Korteweg-de Vries equations. When the modulum m →1, those periodic solutions degenerate as the corresponding solitary wave and shock wave ones. Especially, exact solutions for the three-component system are presented in detail and graphically.

关键词： multi-component modified Korteweg-de Vries equations Jacobi elliptic function Hyperbolic solution symbolic computation

Garlicin Post-conditioning Suppresses Adhesion Molecules in Porcine Model of Myocardial Ischemia-Reperfusion Injury

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Chinese Journal of Integrative Medicine 2019年第1期25卷 31-36页

作者： YANG Peng li Jia-hui li Ai-li li Jing WANG Yong REN Shi-yan li Xian-lun Department of Cardiology China-Japan Friendship Hospital

Objective: To evaluate whether garlicin post-conditioning can attenuate myocardial ischemiareperfusion injury in a catheter-based porcine model of acute myocardial infarction(AMI) by affecting adhesion molecules integrin β1/CD29 and platelet endothelial cell adhesion molecule-1(PECAM-1/CD31). Methods: Twenty-two swine were devided into 3 groups: 6 in a sham-operation group, and 8 each in the model and garlicin groups. AMI porcine model was established in the model and garlicin groups. The distal parts of the left anterior descending coronary artery in the animals of the model and garlicin groups were occluded by dilated balloon for 2 h, followed by reperfusion for 3 h. Garlicin(1.88 mg/kg) was injected over a period of 1 h, beginning just before reperfusion, in the garlicin group. Real-time polymerase chain reaction, immunohistochemistry and Western blot were carried out to detect mRNA and protein expressions of CD29 and CD31 3 h after reperfusion. Results: Hematoxylin-eosin staining showed a better myocardial structure in the garlicin group after reperfusion. Compared to the model group, garlicin inhibited both the mRNA and protein expression of CD29 and CD31 in reperfusion area and no-reflow area(both Plicin post-conditioning induced cardio-protection against myocardial ischemia-reperfusion injury in this catheter-based porcine model of AMI. The cardio-protective effect of garlicin is possibly owing to suppression of production of CD29 and CD31, by inhibition of the m RNA expression of CD29 and CD31.

关键词： garlicin reperfusion injury myocardial infarction CD29 CD31

Effects of brain-derived neurotrophic factor on induced differentiation of SH-SY5Y cells in vitro

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Neural Regeneration Research 2009年第12期4卷 1062-1067页

作者： Jiao li Jingqi li Xueli li lixia Lu Lei Xu Department of Biochemistry and Molecular Biology Medical School Tongji University Shanghai 200092 China

BACKGROUND： Previous studies have demonstrated that brain-derived neurotrophic factor （BDNF） promotes neural differentiation. However, the mechanisms involved in cell cycle-related protein regulation, which highly correlates to neural proliferation and apoptosis, remain poorly understood. OBJECTIVE： To investigate the effects of various concentrations of BDNF on cycle-related protein mRNA expression in induce-differentiated SH-SY5Y cells in vitro prior to and following G2 phase, and to analyze the neuroprotective effects of BDNF. DESIGN, TIME AND SETTING： A comparison, observational study, based on cell biology, was performed at the Department of Biochemistry, Medical College of Tongji University, from March 2005 to October 2006. MATERIALS： SH-SY5Y cells were provided by Shanghai Institute of Cytology, Chinese Academy of Science; BDNF by Alomone Labs, Israel; all-trans retinoic acid （ATRA） by Sigma-Aldrich, USA. METHODS： SH-SY5Y cells were randomly divided into three groups： blank control [cells were treated in Insulin-Transferrin-Selenium （ITS） solution for 7 days], ATRA （cells were treated with ITS solution containing 10 μmol/L ATRA for 7 days）, and BDNF （cells were treated identical to the ATRA group for 5 days, and then respectively treated in ITS solution containing 1, 10, and 100 μg/L BDNF for 2 days）. The experiment was repeated three times for each group. MAIN OUTCOME MEASURES： mRNA expression levels of cyclin A1, B1, B2, cyclin-dependent kinase 1, and 5 were detected using quantitative real-time RT-PCR; percentage of cells in G1, S, and G2 phases were detected using fluorescence-activated cell sorting. RESULTS： mRNA expression levels of cyclin A1 in the high-dose BDNF group was significantly less than the ATRA group （P 〈 0.05）.mRNA expression levels of cyclin B1 was significantly less in the different BDNF concentration groups compared with the control and ATRA groups （P 〈 0.05 or P 〈 0.01）. mRNA expression levels of cyclin B2 and cyclin-dependent kinase 1

关键词： brain-derived neurotrophic factor induced differentiation cell cycle-related protein quantitative real-time RT-PCR fluorescence-activated cell sorting SH-SY5Y cell line

How does trip frequency distort time value to impact congestion charging schemes?

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Transportation Safety and Environment 2024年第1期6卷 22-39页

作者： Maosheng li Hangcong li School of Traffic and Transportation Engineering Central South UniversityChangshaHunan 410075China

A notable feature of a city or region with close economic and social connections with its neighbours is its highly mixed local and external traffic,and in some cases the external traffic volume is almost as high as that of local *** local traffic volume may be largely made up of the same regular local commuters making frequent trips,external traffic from outside of the city(region)may not be the same people making regular trips to/from the ***,from a large pool of people making infrequent trips to/from the city,the existence of external traffic is proven by data from the licence plate recognition system of road vehicles in Changde,*** function of value of time correlated with the income/wage rate and trip frequency is exploited and verified *** time value distorted by trip frequency is defined as perceived time value(PTV),which also influences the way travellers perceive any travel impedance such as congestion delay and toll *** paper analyses the price of anarchy(POA)when explicitly considering the travel frequency of the trip-makers and their PTV,and compares with previous analysis without considering travel *** show that when travel frequency is considered,the optimal toll of congested road pricing schemes which converts road traffic flow from user equilibrium into system optimization is much lower than that without considering travel *** cost of licence plate auction cannot be treated as a congestion toll,which is only a threshold of vehicle *** travellers choose routes by PTV rather than TV(time value)is proven by an example of Heishipu Bridge in Changsha,Hunan Province,China.

关键词： road congestion charging travel frequency perceived time value road traffic impedance price of anarchy

Dual-calibration coefficient:a more accurate protocol for simultaneous determination of superoxide and hydrogen peroxide in human Hep G2 cell extracts

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Science China Chemistry 2015年第5期58卷 825-829页

作者： Hongmin li Lu li Xu Wang Qingling li Miao Du Bo Tang College of Chemistry Chemical Engineering and Materials Science Collaborative Innovation Center of Functionalized Probes for Chemical Imaging in Universities of Shandong Key Laboratory of Molecular and Nano Probes Ministry of Education Shandong Provincial Key Laboratory of Clean Production of Fine Chemicals Shandong Normal University Department of Chemistry Research Center of Low-Dimensional and Functional Nano-Materials Qilu Normal University

We present a more accurate method for the quantification of superoxide anion （02-） and hydrogen peroxide （H202） simulta- neously in human HepG2 cell extracts. After the xanthine/xanthine oxidase system was added into cell extract which was devoid of O2＊- and H202, steady-state and in-situ produced O2＊- and H202 by xanthine/xanthine oxidase system was labeled by fluorescent probes and subsequently separated by microchip electrophoresis. Based on this method, two differential equations with the calibration coefficients were established for O2 and H202, respectively. Using the established dual-calibration coefficients, we obtained the calibrated concentrations of 02＊ and H202 that produced in human HepG2 cells, which were lower （0.66±0.03 and 0.82±0.04 lamol/L for 02＊-and H202, respectively） than that （0.85±0.03 and 0.96±0.03 gmol/L for O. and H202, respectively） obtained from statutory working curve. The proposed dual-calibration coefficient protocol takes into account both the complex matrix effect of the biological system and real time decaying of O2 ＊- and H202, providing a method with higher accuracy.

关键词： calibration coefficient superoxide hydrogen peroxide microchip electrophoresis HepG2 cell extracts

Correlation Between Dynamic Compressive Strength and Fracture Behaviors of Bulk Metallic Glasses

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Acta Metallurgica Sinica(English Letters) 2020年第10期33卷 1407-1415页

作者： Wenqing li Zhengwang Zhu Guojie li Long Zhang Zhengkun li Huameng Fu Hongwei Zhang Hong li Aimin Wang Haifeng Zhang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China Beijing Institute of Space Long March Vehicle Beijing 10076China

The mechanical behaviors of Zr43.5Cu43.5Ni4Al8Nb1,Zr55.4Cu31.6Ni4Al8Nb1,Ti32.8Zr30.2Ni5.3Cu9Be22.7(at.%)metallic glass at different strain rates were *** all the present alloys,the dispersion over 700 MPa was observed on the strength in the repeated dynamic compressions,which was much stronger than that of the quasi-static compressive *** the dispersion of the dynamic compressive strength was well correlated with the corresponding fracture *** area of fracture surface was calculated and also showed a strong dispersion for all the fractured specimens tested at the strain rate of 500 s^-1 and 1000 s^-*** the specimens showed a linear relationship between the square of dynamic compressive strength and the area of fracture surface in the dynamic compression *** phenomenon was mainly thought to be related to the difference of mean initial free volume concentration of different samples,stress concentration caused by the split Hopkinson pressure bar experimental setup and high sensitivity of defects under dynamic *** findings were beneficial to deeply understand the effect of strain rate on the mechanical properties of the metallic glass.

关键词： Metallic glass Dynamic compression Weibull statistics Shear bands

Humanoid robot heads for human-robot interaction:A review

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Science China(Technological Sciences) 2024年第2期67卷 357-379页

作者： li Yi ZHU liXiang ZHANG ZiQian GUO MingFei li ZhiXin li YanBiao HASHIMOTO Minoru Key Laboratory of Special Purpose Equipment and Advanced Processing Technology of Ministry of Education Zhejiang University of TechnologyHangzhou 310023China Zhejiang Provincial Key Laboratoryof Special Purpose Equipment and Advanced Processing Technology Zhejang Universityof Technology Hangzhou 310023 China Faculy of Textile Science and Technology Shinshu UniversityUeda 386-8567Japan

The humanoid robot head plays an important role in the emotional expression of human-robot interaction(HRI).They are emerging in industrial manufacturing,business reception,entertainment,teaching assistance,and tour *** recent years,significant progress has been made in the field of humanoid ***,there is still a lack of humanoid robots that can interact with humans naturally and *** review comprises a comprehensive survey of state-of-the-art technologies for humanoid robot heads over the last three decades,which covers the aspects of mechanical structures,actuators and sensors,anthropomorphic behavior control,emotional expression,and human-robot ***,the current challenges and possible future directions are discussed.

关键词： humanoid robot head anthropomorphic behaviors emotional expression human-robot interaction

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