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A glutamatergic Sp5C-STN circuit mediates chronic migraine in mice 被引量:1
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作者 TANG Liu CHENG Ying-Qi +1 位作者 GUI Wei ZHANG Yan 《生理学报》 北大核心 2026年第1期159-172,共14页
Chronic migraine(CM)is a prevalent and highly debilitating neurological disorder.Functional magnetic resonance imaging(fMRI)studies have demonstrated associations between abnormal brain region activation and CM,yet th... Chronic migraine(CM)is a prevalent and highly debilitating neurological disorder.Functional magnetic resonance imaging(fMRI)studies have demonstrated associations between abnormal brain region activation and CM,yet the underlying complex neural circuitry mechanisms remain unclear.The spinal trigeminal nucleus caudalis(Sp5C)serves as the primary central hub for orofacial nociceptive input,receiving trigeminal pain signals and projecting to higher-order centers such as the thalamus.Therefore,we sought to investigate whether the Sp5C region and its associated circuits were involved in CM pathogenesis.In this study,we established a CM mouse model through repeated intraperitoneal injections of nitroglycerin(NTG).Using a combination of in vivo fiber photometry and in vitro c-Fos immunohistochemistry,we found a marked periorbital and plantar mechanical allodynia in CM mice,accompanied by increased glutamatergic neuronal activity in Sp5C.Chemogenetic manipulation of Sp5C glutamatergic neurons(Sp5CV^(glut2))bidirectionally modulated migraine-like behaviors and induced pain-related affective states,as evidenced by conditioned place preference/aversion(CPP/CPA)paradigms.Anterograde viral tracing revealed dense projections from Sp5C^(Vglut2)to the subthalamic nucleus(STN),which was activated in CM mice.Optogenetic activation of the Sp5C-STN pathway similarly produced migraine-like behaviors and pain-related aversive memory in mice.Altogether,we revealed a critical role of the Sp5CVglut2-STN circuit in the development and modulation of CM.Our findings provide novel mechanistic insights into the central mechanisms underlying CM,establishing potential theoretical foundations for clinical diagnosis and therapeutic development. 展开更多
关键词 chronic migraine spinal trigeminal nucleus caudalis subthalamic nucleus neural circuit
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Separation of Three Major Active Components from Eleutherine americana Merr.et K.Heyne Using High-speed Counter-current Chromatography Combined with Silica Gel Column Chromatography
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作者 Wanyu ZUO Yalan LUO +2 位作者 Bingyu CHENG Luyang LU Jizhong ZHANG 《Medicinal Plant》 2025年第6期17-21,共5页
[Objectives]To establish an efficient and environmentally friendly separation and purification method for the large-scale preparation of the major active components-eleutherol,eleutherine,and isoeleutherine-from the e... [Objectives]To establish an efficient and environmentally friendly separation and purification method for the large-scale preparation of the major active components-eleutherol,eleutherine,and isoeleutherine-from the ethnomedicinal plant Eleutherine americana Merr.et K.Heyne.[Methods]The sample of E.americana bulbs was initially extracted with ethanol,followed by three successive extractions with ethyl acetate-water(2:1,V/V)to obtain the target component-enriched fraction.Eight solvent systems were systematically optimized,and a mixture of petroleum ether-ethyl acetate-ethanol-water(5:5:6:4,V/V/V/V)was identified as the optimal solvent system for high-speed counter-current chromatography(HSCCC)separation under conditions of 900 rpm,2 mL/min,and 35℃.The crude HSCCC product was further purified by silica gel column chromatography(200-300 mesh)using gradient elution with a solvent system of n-hexane-dichloromethane-ethyl acetate(varying from 10:5:1 to 4:5:1,V/V/V).UPLC-PDA(Agilent SB-C_(18)column)and nuclear magnetic resonance spectroscopy(600 MHz)were comprehensively employed to assess compound purity and confirm molecular structures.[Results]An optimized technique integrating HSCCC and silica gel column chromatography was established,successfully enabling the large-scale preparation of three bioactive components:eleutherol(purity 99%),eleutherine(purity 98%),and isoeleutherine(purity 98%).Structural identification results were consistent with those reported in the literature.Compared to traditional methods,the new approach demonstrated improved separation efficiency and reduced solvent consumption.[Conclusions]The combined separation method utilizing HSCCC and silica gel column chromatography established in this study demonstrates notable advantages,including high efficiency,environmental friendliness,and cost-effectiveness,enabling the large-scale preparation of the three major active components from E.americana.This approach outperforms conventional methods by offering higher separation efficiency,reduced solvent consumption,and superior product purity,providing a robust technical solution for the development and utilization of bioactive compounds from E.americana.Moreover,it offers a novel methodological reference for the isolation and purification of other natural products. 展开更多
关键词 Eleutherine americana High-speed counter-current chromatography(HSCCC) Silica gel column chromatography Separation and purification
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Multi-target neural circuit reconstruction and enhancement in spinal cord injury 被引量:2
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作者 Lingyun Cao Siyun Chen +2 位作者 Shuping Wang Ya Zheng Dongsheng Xu 《Neural Regeneration Research》 2026年第3期957-971,共15页
After spinal cord injury,impairment of the sensorimotor circuit can lead to dysfunction in the motor,sensory,proprioceptive,and autonomic nervous systems.Functional recovery is often hindered by constraints on the tim... After spinal cord injury,impairment of the sensorimotor circuit can lead to dysfunction in the motor,sensory,proprioceptive,and autonomic nervous systems.Functional recovery is often hindered by constraints on the timing of interventions,combined with the limitations of current methods.To address these challenges,various techniques have been developed to aid in the repair and reconstruction of neural circuits at different stages of injury.Notably,neuromodulation has garnered considerable attention for its potential to enhance nerve regeneration,provide neuroprotection,restore neurons,and regulate the neural reorganization of circuits within the cerebral cortex and corticospinal tract.To improve the effectiveness of these interventions,the implementation of multitarget early interventional neuromodulation strategies,such as electrical and magnetic stimulation,is recommended to enhance functional recovery across different phases of nerve injury.This review concisely outlines the challenges encountered following spinal cord injury,synthesizes existing neurostimulation techniques while emphasizing neuroprotection,repair,and regeneration of impaired connections,and advocates for multi-targeted,task-oriented,and timely interventions. 展开更多
关键词 multi-targets nerve root magnetic stimulation neural circuit NEUROMODULATION peripheral nerve stimulation RECONSTRUCTION spinal cord injury task-oriented training TIMING transcranial magnetic stimulation
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Machine learning of chaotic characteristics in classical nonlinear dynamics using variational quantum circuit
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作者 Sheng-Chen Bai Shi-Ju Ran 《Chinese Physics B》 2026年第2期322-328,共7页
Replicating the chaotic characteristics inherent in nonlinear dynamical systems via machine learning(ML)is a key challenge in this rapidly advancing interdisciplinary field.In this work,we explore the potential of var... Replicating the chaotic characteristics inherent in nonlinear dynamical systems via machine learning(ML)is a key challenge in this rapidly advancing interdisciplinary field.In this work,we explore the potential of variational quantum circuits(VQC)for learning the stochastic properties of classical nonlinear dynamical systems.Specifically,we focus on the one-and two-dimensional logistic maps,which,while simple,remain under-explored in the context of learning dynamical characteristics.Our findings reveal that,even for such simple dynamical systems,accurately replicating longterm characteristics is hindered by a pronounced sensitivity to overfitting.While increasing the parameter complexity of the ML model typically enhances short-term prediction accuracy,it also leads to a degradation in the model’s ability to replicate long-term characteristics,primarily due to the detrimental effects of overfitting on generalization power.By comparing the VQC with two widely recognized classical ML techniques,which are long short-term memory(LSTM)networks for timeseries processing and reservoir computing,we demonstrate that VQC outperforms these methods in terms of replicating long-term characteristics.Our results suggest that for the ML of dynamics,it is demanded to develop more compact and efficient models(such as VQC)rather than more complicated and large-scale ones. 展开更多
关键词 variational quantum circuit machine learning CHAOS
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Energy dynamics and circuit implementation for a neuron with a memcapacitive membrane
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作者 Binchi WANG Yitong GUO +1 位作者 Guodong REN Jun MA 《ENGINEERING Information Technology & Electronic Engineering》 2026年第1期59-70,共12页
The output voltages for the capacitive elements of a neural circuit model can be mapped into dimensionless capacitive variables,which present firing patterns similar to the membrane potentials detected in biological n... The output voltages for the capacitive elements of a neural circuit model can be mapped into dimensionless capacitive variables,which present firing patterns similar to the membrane potentials detected in biological neurons.The inclusion of a memcapacitor also en‐ables consideration of membrane deformation effects,enhancing the model’s capacity to simulate neuronal behavior across varying physio‐logical and environmental conditions.In this study,a capacitor and a memcapacitor are connected through a linear resistor in parallel with other electric components in different branch circuits composed of an inductor and a nonlinear resistor.The electrical activities in a neuron with a double-layer membrane and two capacitive variables are discussed in detail after converting the nonlinear equations for the neural circuit into a theoretical neuron model.A dimensionless neuron model and its corresponding energy function are derived.The field energy function for the neural circuit is converted into an equivalent Hamilton energy function and further validated via the Helmholtz theorem.Furthermore,the average value of energy serves as an indicator for predicting stochastic resonance,as supported by analyzing the distribu‐tion of the coefficient of variation.The neuronal firing patterns are shown to be energy-dependent.An adaptive control strategy is proposed to regulate mode transitions in electrical activities of the neuron.An analog equivalent circuit is constructed to experimentally verify the nu‐merical results,thereby supporting the reliability of the proposed neuron model. 展开更多
关键词 Neural circuit Neuron model Hamilton energy Memcapacitor Coherence resonance
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Single-shot wavefront sensing enabled by a photonic integrated circuit
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作者 Wenyu Chen Zixin Zhao +3 位作者 Shiyuan Liu Hui Deng Liang Gao Jinlong Zhu 《Advanced Photonics Nexus》 2026年第1期131-139,共9页
Point-of-care diagnostics and inline quantitative phase imaging(QPI)drive the demand for portable,ultra-miniaturized,and robust optical imaging and metrology systems.We propose and demonstrate a wavefront sensor integ... Point-of-care diagnostics and inline quantitative phase imaging(QPI)drive the demand for portable,ultra-miniaturized,and robust optical imaging and metrology systems.We propose and demonstrate a wavefront sensor integrated into a photonic integrated circuit,enabling single-shot optical phase retrieval.We implemented an integrated wavefront sensor array with a spatial resolution of 17μm and a numerical aperture of 0.1.Furthermore,we experimentally demonstrated the reconstruction of wavefronts defined by Zernike polynomials,specifically the first 14 terms(Z_(1)to Z_(14)),achieving an average root mean square error below 0.07.This advancement paves the way for fully integrated,portable,and robust optical imaging systems,facilitating integrated wavefront sensors in demanding applications such as point-of-care diagnostics,endoscopy,in situ QPI,and inline surface profile measurement. 展开更多
关键词 wavefront sensing photonic integrated circuit computational imaging miniaturized optical system
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Neural circuit mechanisms of epilepsy:Maintenance of homeostasis at the cellular,synaptic,and neurotransmitter levels
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作者 Xueqing Du Yi Wang +2 位作者 Xuefeng Wang Xin Tian Wei Jing 《Neural Regeneration Research》 2026年第2期455-465,共11页
Epilepsy,a common neurological disorder,is characterized by recurrent seizures that can lead to cognitive,psychological,and neurobiological consequences.The pathogenesis of epilepsy involves neuronal dysfunction at th... Epilepsy,a common neurological disorder,is characterized by recurrent seizures that can lead to cognitive,psychological,and neurobiological consequences.The pathogenesis of epilepsy involves neuronal dysfunction at the molecular,cellular,and neural circuit levels.Abnormal molecular signaling pathways or dysfunction of specific cell types can lead to epilepsy by disrupting the normal functioning of neural circuits.The continuous emergence of new technologies and the rapid advancement of existing ones have facilitated the discovery and comprehensive understanding of the neural circuit mechanisms underlying epilepsy.Therefore,this review aims to investigate the current understanding of the neural circuit mechanisms in epilepsy based on various technologies,including electroencephalography,magnetic resonance imaging,optogenetics,chemogenetics,deep brain stimulation,and brain-computer interfaces.Additionally,this review discusses these mechanisms from three perspectives:structural,synaptic,and transmitter circuits.The findings reveal that the neural circuit mechanisms of epilepsy encompass information transmission among different structures,interactions within the same structure,and the maintenance of homeostasis at the cellular,synaptic,and neurotransmitter levels.These findings offer new insights for investigating the pathophysiological mechanisms of epilepsy and enhancing its clinical diagnosis and treatment. 展开更多
关键词 chemical genetics hippocampus literature review neural circuits NEUROTRANSMITTER OPTOGENETICS pathogenesis SEIZURE synapses THALAMUS
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Integrated Multiport Flexible Voltage Clamp Circuit Breaker with DC Chopper Applied to MMC-HVDC System
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作者 Guoqing Li Yuheng Song +3 位作者 Jing Bian Yanxu Wang Kefei Yan Menghan Li 《CSEE Journal of Power and Energy Systems》 2026年第1期352-365,共14页
Given the wide application of DC grids,the protection equipment of power grids must be improved during the fault period.This study proposes an integrated multiport flexible voltage clamp circuit breaker with a DC chop... Given the wide application of DC grids,the protection equipment of power grids must be improved during the fault period.This study proposes an integrated multiport flexible voltage clamp circuit breaker with a DC chopper acting on the receiving end converter to solve the DC short circuit fault and surplus power because of AC low-voltage fault;it has a modular design.As a DC circuit breaker,the device utilizes the voltage-clamping principle and thyristor semi-control to remove faults.As the fault current increases,the branch circuit outputs different voltage levels by selecting different gears,thereby controlling the voltage-clamping effect.This device can distinguish between different fault types to prevent secondary shocks in the system.As a DC chopper,the voltage at both ends of the energy dissipation resistor is varied by switching submodules,consuming surplus power to complete AC low-voltage faults and minimizing the impact of low-voltage faults on the system’s transmission capacity.Finally,the effectiveness and applicability of the equipment are verified using wind turbines connected to a flexible DC transmission three-terminal power grid model in PSCAD/EMTDC,and two fault simulation types are analyzed.A comparison of the electrical quantities(fault current,system voltage and branch voltage)of the proposed circuit breaker with other similar equipment shows that due to the efficiency of the proposed equipment,the peak fault current is reduced by at least 35.8%.The required voltage stress of key power electronic equipment is reduced by at least 71.5%.Therefore,the equipment ensures that the per-unit voltage of the DC system does not exceed 1.05 during AC fault crossing. 展开更多
关键词 DC Chopper flexibility voltage clamp multiport DC circuit breaker reclosing scheme THYRISTOR
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Transplantation of human neural stem cells repairs neural circuits and restores neurological function in the stroke-injured brain
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作者 Peipei Wang Peng Liu +7 位作者 Yingying Ding Guirong Zhang Nan Wang Xiaodong Sun Mingyue Li Mo Li Xinjie Bao Xiaowei Chen 《Neural Regeneration Research》 2026年第3期1162-1171,共10页
Exogenous neural stem cell transplantation has become one of the most promising treatment methods for chronic stroke.Recent studies have shown that most ischemia-reperfusion model rats recover spontaneously after inju... Exogenous neural stem cell transplantation has become one of the most promising treatment methods for chronic stroke.Recent studies have shown that most ischemia-reperfusion model rats recover spontaneously after injury,which limits the ability to observe long-term behavioral recovery.Here,we used a severe stroke rat model with 150 minutes of ischemia,which produced severe behavioral deficiencies that persisted at 12 weeks,to study the therapeutic effect of neural stem cells on neural restoration in chronic stroke.Our study showed that stroke model rats treated with human neural stem cells had long-term sustained recovery of motor function,reduced infarction volume,long-term human neural stem cell survival,and improved local inflammatory environment and angiogenesis.We also demonstrated that transplanted human neural stem cells differentiated into mature neurons in vivo,formed stable functional synaptic connections with host neurons,and exhibited the electrophysiological properties of functional mature neurons,indicating that they replaced the damaged host neurons.The findings showed that human fetal-derived neural stem cells had long-term effects for neurological recovery in a model of severe stroke,which suggests that human neural stem cells-based therapy may be effective for repairing damaged neural circuits in stroke patients. 展开更多
关键词 behavioral recovery circuit repair electrophysiological properties functional integration human neural stem cell transplantation infarction volume STROKE synaptic tracing
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A Composite Multi-Port Hybrid DC Circuit Breaker with DC Power Flow and Fault Current Limitation Abilities
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作者 Xiaoya Chen Chao Zhang +5 位作者 Xufeng Yuan Wei Xiong Zhiyang Lu Huajun Zheng Yutao Xu Zhukui Tan 《Energy Engineering》 2026年第3期306-325,共20页
To address the issues of high costs and low component utilization caused by the independent configuration of hybrid DC circuit breakers(HCBs)and DC power flow controllers(DCPFCs)at each port in existing DC distributio... To address the issues of high costs and low component utilization caused by the independent configuration of hybrid DC circuit breakers(HCBs)and DC power flow controllers(DCPFCs)at each port in existing DC distribution networks,this paper adopts a component sharing mechanism to propose a composite multi-port hybrid DC circuit breaker(CM-HCB)with DC power flow and fault current limitation abilities,as well as reduced component costs.The proposed CM-HCB topology enables the sharing of the main breaker branch(MB)and the energy dissipation branch,while the load commutation switches(LCSs)in the main branch are reused as power flow control components,enabling flexible regulation of power flow in multiple lines.Meanwhile,by reconstructing the current path during the fault process,the proposed CM-HCB can utilize the internal coupled inductor to limit the current rise rate at the initial stage of the fault,significantly reducing the requirement for breaking current.A detailed study on the topological structure,steady-state power flow regulation mechanism,transient fault isolation mechanism,control strategy and characteristic analysis of the proposed CM-HCB is presented.Then,a Matlab/Simulink-based meshed three-terminal DC grid simulation platform with the proposed CM-HCB is built.The results indicate that the proposed CM-HCB can not only achieve flexible power flow control during steady-state operation,but also obtain current rise limitation and fault isolation abilities under short-circuit fault conditions,verifying its correctness and effectiveness.Finally,a comparative economic analysis is conducted between the proposed CM-HCB and the other two existing solutions,confirming that its component sharing mechanism can significantly reduce the number of components,lower system costs,and improve component utilization. 展开更多
关键词 DC power grid DC power flow control fault current limiting fault isolation hybrid DC circuit breaker
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Activity-dependent regulation of cortical cell numbers:Role of neuronal activity in cortical circuit formation
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作者 Fong Kuan Wong 《Neural Regeneration Research》 2026年第8期3521-3522,共2页
The mammalian cerebral cortex,despite its variation in brain shape and size,is a stereotypical six-layered structure composed of pyramidal cells,interneurons,astrocytes,microglia,oligodendrocytes,and endothelial cells... The mammalian cerebral cortex,despite its variation in brain shape and size,is a stereotypical six-layered structure composed of pyramidal cells,interneurons,astrocytes,microglia,oligodendrocytes,and endothelial cells.During development,these cells differ in their origin,birth timing,and developmental trajectories.Nonetheless,they converge during development,forming nascent cortical circuits crucial for organismal behavior.While the relative proportions of cortical cells vary between regions. 展开更多
关键词 neuronal activity mammalian cerebral cortex pyramidal cellsinterneuronsastrocytesmicrogliaoligodendrocytesand cortical cell numbers nascent cortical circuits endothelial cellsduring activity dependent cortical cells
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Preparative isolation and purification of 12,13-dihydroxyeuparin from Radix Eupatorii Chinensis by high-speed counter-current chromatography 被引量:2
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作者 Mei Yang Xin-Jun Xu +3 位作者 Chun-Yan Xie Jie-Yun Huang Zhi-Sheng Xie De-Po Yang 《Journal of Pharmaceutical Analysis》 SCIE CAS 2012年第4期258-263,共6页
An efficient method for the isolation and purification of 12,13-dihydroxyeuparin from Radix Eupatorii Chinensis by high speed counter-current chromatography(HSCCC)was established in this paper.The ether extracts of Ra... An efficient method for the isolation and purification of 12,13-dihydroxyeuparin from Radix Eupatorii Chinensis by high speed counter-current chromatography(HSCCC)was established in this paper.The ether extracts of Radix Eupatorii Chinensis were purified by HSCCC with a solvent system of hexyl hydride-ethyl acetate-methanol-water(1:2:1:2,v/v/v/v).The upper phase was used as the stationary phase and the lower phase as the mobile phase.About 8.4 mg of 12,13-dihydroxyeuparin was obtained from 200 mg of ether extracts from Radix Eupatorii Chinensis in one-step HSCCC separation,with the purity of 96.71%,as determined by HPLC.After methanol-water recrystallization,the purity of 12,13-dihydroxyeuparin reached 99.83%.Such a simple and effective method was fairly useful to prepare pure compound as reference substances for related study on Radix Eupatorii Chinensis. 展开更多
关键词 Radix Eupatorii Chinensis High speed counter-current chromatography(HSCCC) 12 13-dihydroxyeuparin
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An Economical Method for Preparative Purification of Five Alkaloids from Coptis Chinensis Franch by High-Speed Counter-Current Chromatography Using Singled Prepared Solvent System by GC 被引量:1
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作者 Lianhong Yin Lina Xu +5 位作者 Xiaona Wang Binan Lu Yingnan Li Mingming Hu Yuetao Liu Jinyong Peng 《American Journal of Analytical Chemistry》 2011年第4期411-421,共11页
Coptis chinensis Franch, a widely used Traditional Chinese Medicine, shows various kinds of bioactivity. The major active components of the herb are considered to be alkaloids. Thus, preparative separation of these al... Coptis chinensis Franch, a widely used Traditional Chinese Medicine, shows various kinds of bioactivity. The major active components of the herb are considered to be alkaloids. Thus, preparative separation of these alkaloids is critical important for further pharmacology and mechanism studies. In the paper, five alkaloids from C. chinensis were purified by HSCCC using the solvent system composed of chloro-form-metha- nol-water (2:1:1, v/v/v) single prepared. The content of each solvent in solvent system were determined by gas chromatography (GC), then according the ratios of solvents in each phase to prepare the mobile and stationary phase respectively. And a comparative study was carried out between together preparation and single preparation of the solvent system. The purities and recoveries of all the products were over 98.5% and 92%. However, 134 mL chloroform, 336 mL methanol and 452 mL water were saved when the two phase were singled by GC. Our research showed an economical method for separating alkaloids from C. chinensis by HSCCC using the solvent system single prepared by GC. 展开更多
关键词 ALKALOID Coptis CHINENSIS Franch High Speed counter-current Chromaotgraphy Gas CHROMATOGRAPHY Solvent System
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Separation and Purification of Acetophenones from Cynanchum bengei Decne Root Bark by Combination of Silica Gel and High-speed Counter-current Chromatography 被引量:1
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作者 Huaizhi LI Lingchuan XU +4 位作者 Xiao WANG Qian LIU Jia LI Peng YANG Bingtian YANG 《Medicinal Plant》 2017年第2期8-11,共4页
[Objectives] To develop a method for separation and purification of acetophenones from Cynanchum bengei Decne root bark by combination of silica gel and high-speed counter-current chromatography( HSCCC). [Methods]The ... [Objectives] To develop a method for separation and purification of acetophenones from Cynanchum bengei Decne root bark by combination of silica gel and high-speed counter-current chromatography( HSCCC). [Methods]The crude extract of Cynanchum bengei Decne root bark was separated by silica gel column chromatography,and parts A and B containing acetophenones were obtained. Then,parts A and B were separated by HSCCC with a two-phase solvent system composed of petroleum ether-ethyl acetate-methanol-water( 4∶ 6∶ 4. 5∶ 5. 5 and4∶ 6 ∶ 3 ∶ 7, V/V), respectively. [Results] From 260 mg of part A, four compounds with p-dihydroxybenzene 3. 9 mg(Ⅰ),4-hydroxyacetophenone 17. 1 mg( Ⅱ),2,5-di-hydroxyacetophenone 13. 3 mg(Ⅲ) and 2,4-dihydroxyaceto-phenone 21. 0 mg(Ⅳ) were obtained. And from 300 mg of part B,136 mg of Radix Cynanchi Bungei benzophenone(Ⅴ) was obtained. The purity of compounds determined by HPLC was 97. 0%,96. 6%,99. 2%,99. 7%,99. 5%,respectively. [Conclusions] The established method is simple and efficient. It can be used for separation of acetophenones from Cynanchum bengei Decne root bark and has better practical value,which could provide a reference basis for development and utilization of Cynanchum bengei Decne root bark. 展开更多
关键词 Silica GEL column CHROMATOGRAPHY High-speed counter-current chromatography(HSCCC) Acetophenones CYNANCHUM bengei Decne root BARK
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Comparison of Co-Current and Counter-Current Flow Fields on Extraction Performance in Micro-Channels
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作者 Subramaniam Pushpavanam Benny Malengier 《Advances in Chemical Engineering and Science》 2012年第2期309-320,共12页
Several applications such as liquid-liquid extraction in micro-fluidic devices are concerned with the flow of two immiscible liquid phases. The commonly observed flow regimes in these systems are slug-flow and stratif... Several applications such as liquid-liquid extraction in micro-fluidic devices are concerned with the flow of two immiscible liquid phases. The commonly observed flow regimes in these systems are slug-flow and stratified flow. The latter regime in micro-channels has the inherent advantage that separation of the two liquids at the exit is efficient. Recently extraction in a stratified counter-current flow has been studied experimentally and it has been shown to be more efficient than co-current flow. An analytical as well as a numerical method to determine the steady-state solution of the corresponding convection-diffusion equation for the two flow-fields is presented. It is shown that the counter-current process is superior to the co-current process for the same set of parameters and operating conditions. A simplified model is proposed to analyse the process when diffusion in the transverse direction is not rate limiting. Different approaches to determining mass transfer coefficient are compared. The concept of log mean temperature difference used in design of heat exchangers is extended to describe mass transfer in the system. 展开更多
关键词 PLUG Flow DIFFUSION Extraction CO-CURRENT counter-current
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Behavioral Animal Models and Neural-Circuit Framework of Depressive Disorder 被引量:5
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作者 Xiangyun Tian Scott J.Russo Long Li 《Neuroscience Bulletin》 2025年第2期272-288,共17页
Depressive disorder is a chronic,recurring,and potentially life-endangering neuropsychiatric disease.According to a report by the World Health Organization,the global population suffering from depression is experienci... Depressive disorder is a chronic,recurring,and potentially life-endangering neuropsychiatric disease.According to a report by the World Health Organization,the global population suffering from depression is experiencing a significant annual increase.Despite its prevalence and considerable impact on people,little is known about its pathogenesis.One major reason is the scarcity of reliable animal models due to the absence of consensus on the pathology and etiology of depression.Furthermore,the neural circuit mechanism of depression induced by various factors is particularly complex.Considering the variability in depressive behavior patterns and neurobiological mechanisms among different animal models of depression,a comparison between the neural circuits of depression induced by various factors is essential for its treatment.In this review,we mainly summarize the most widely used behavioral animal models and neural circuits under different triggers of depression,aiming to provide a theoretical basis for depression prevention. 展开更多
关键词 DEPRESSION Animal models STRESS Neural circuits
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MET receptor tyrosine kinase promotes the generation of functional synapses in adult cortical circuits
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作者 Yuehua Cui Xiaokuang Ma +7 位作者 Jing Wei Chang Chen Neha Shakir Hitesch Guirram Zhiyu Dai Trent Anderson Deveroux Ferguson Shenfeng Qiu 《Neural Regeneration Research》 SCIE CAS 2025年第5期1431-1444,共14页
Loss of synapse and functional connectivity in brain circuits is associated with aging and neurodegeneration,however,few molecular mechanisms are known to intrinsically promote synaptogenesis or enhance synapse functi... Loss of synapse and functional connectivity in brain circuits is associated with aging and neurodegeneration,however,few molecular mechanisms are known to intrinsically promote synaptogenesis or enhance synapse function.We have previously shown that MET receptor tyrosine kinase in the developing cortical circuits promotes dendritic growth and dendritic spine morphogenesis.To investigate whether enhancing MET in adult cortex has synapse regenerating potential,we created a knockin mouse line,in which the human MET gene expression and signaling can be turned on in adult(10–12 months)cortical neurons through doxycycline-containing chow.We found that similar to the developing brain,turning on MET signaling in the adult cortex activates small GTPases and increases spine density in prefrontal projection neurons.These findings are further corroborated by increased synaptic activity and transient generation of immature silent synapses.Prolonged MET signaling resulted in an increasedα-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid/N-methyl-Daspartate(AMPA/NMDA)receptor current ratio,indicative of enhanced synaptic function and connectivity.Our data reveal that enhancing MET signaling could be an interventional approach to promote synaptogenesis and preserve functional connectivity in the adult brain.These findings may have implications for regenerative therapy in aging and neurodegeneration conditions. 展开更多
关键词 aging circuit connectivity cortical circuits molecular mechanisms neural regeneration NEURODEGENERATION synapses
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Near‑Sensor Edge Computing System Enabled by a CMOS Compatible Photonic Integrated Circuit Platform Using Bilayer AlN/Si Waveguides 被引量:1
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作者 Zhihao Ren Zixuan Zhang +4 位作者 Yangyang Zhuge Zian Xiao Siyu Xu Jingkai Zhou Chengkuo Lee 《Nano-Micro Letters》 2025年第11期1-20,共20页
The rise of large-scale artificial intelligence(AI)models,such as ChatGPT,Deep-Seek,and autonomous vehicle systems,has significantly advanced the boundaries of AI,enabling highly complex tasks in natural language proc... The rise of large-scale artificial intelligence(AI)models,such as ChatGPT,Deep-Seek,and autonomous vehicle systems,has significantly advanced the boundaries of AI,enabling highly complex tasks in natural language processing,image recognition,and real-time decisionmaking.However,these models demand immense computational power and are often centralized,relying on cloud-based architectures with inherent limitations in latency,privacy,and energy efficiency.To address these challenges and bring AI closer to real-world applications,such as wearable health monitoring,robotics,and immersive virtual environments,innovative hardware solutions are urgently needed.This work introduces a near-sensor edge computing(NSEC)system,built on a bilayer AlN/Si waveguide platform,to provide real-time,energy-efficient AI capabilities at the edge.Leveraging the electro-optic properties of AlN microring resonators for photonic feature extraction,coupled with Si-based thermo-optic Mach-Zehnder interferometers for neural network computations,the system represents a transformative approach to AI hardware design.Demonstrated through multimodal gesture and gait analysis,the NSEC system achieves high classification accuracies of 96.77%for gestures and 98.31%for gaits,ultra-low latency(<10 ns),and minimal energy consumption(<0.34 pJ).This groundbreaking system bridges the gap between AI models and real-world applications,enabling efficient,privacy-preserving AI solutions for healthcare,robotics,and next-generation human-machine interfaces,marking a pivotal advancement in edge computing and AI deployment. 展开更多
关键词 Photonic integrated circuits Edge computing Aluminum nitride Neural networks Wearable sensors
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Study of the circuit characteristics between electrodes in a pulsed plasma thruster 被引量:1
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作者 Jiahao WU Zhiwen WU +5 位作者 Tiankun HUANG Bohan ZHANG Chenwei LI Zhonghao MA Yang GAO Yi BEI 《Plasma Science and Technology》 2025年第6期49-58,共10页
In a pulsed plasma thruster,the voltage distribution between the electrodes is a key factor that influences the ionization process.However,few researchers have conducted in-depth studies of this phenomenon in the past... In a pulsed plasma thruster,the voltage distribution between the electrodes is a key factor that influences the ionization process.However,few researchers have conducted in-depth studies of this phenomenon in the past.Reported here are measurements of the voltage distribution between the plates of a parallel-plate pulsed plasma thruster under different discharge voltages,based on which the variations in the total circuit inductance and resistance as well as those between the plates are calculated.The results show that the time-averaged voltage across the plates accounts for 28.7%-50.4%of the capacitor voltage.As the capacitor initial voltage increases from 1250 V to 2000 V,the voltage across the plates rises,but its proportion relative to the capacitor voltage decreases.For every 250 V increase in the capacitor initial voltage,the average voltage proportion across the plates decreases by approximately 2%-3%.Additionally,the voltage proportion decreases gradually from the end near the propellant outward.The voltage distribution ratio between the plates is correlated with the proportions of the resistance and inductance between the plates relative to the total circuit. 展开更多
关键词 pulsed plasma thruster parallel-plate electrodes circuit characteristics voltage distribution on electrodes
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Design and validation of RLC equivalent circuit model based on long-wave infrared metamaterial absorber
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作者 ZHAO Ji-Cong DANG Yan-Meng +3 位作者 HOU Hai-Yang LIN Ye-Fan SUN Hai-Yan ZHANG Kun 《红外与毫米波学报》 北大核心 2025年第1期129-137,共9页
In this paper,we propose an RLC equivalent circuit model theory which can accurately predict the spectral response and resonance characteristics of metamaterial absorption structures,extend its design,and characterize... In this paper,we propose an RLC equivalent circuit model theory which can accurately predict the spectral response and resonance characteristics of metamaterial absorption structures,extend its design,and characterize the parameters of the model in detail.By employing this model,we conducted computations to characterize the response wavelength and bandwidth of variously sized metamaterial absorbers.A comparative analysis with Finite Difference Time Domain(FDTD)simulations demonstrated a remarkable level of consistency in the results.The designed absorbers were fabricated using micro-nano fabrication processes,and were experimentally tested to demonstrate absorption rates exceeding 90%at a wavelength of 9.28μm.The predicted results are then compared with test results.The comparison reveals good consistency in two aspects of the resonance responses,thereby confirming the rationality and accuracy of this model. 展开更多
关键词 METAMATERIAL surface plasmons magnetic dipoles RLC circuit model
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