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Potassium and calcium channels in different nerve cells act as therapeutic targets in neurological disorders
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作者 Qing Qiu Mengting Yang +2 位作者 Danfeng Gong Haiying Liang Tingting Chen 《Neural Regeneration Research》 SCIE CAS 2025年第5期1258-1276,共19页
The central nervous system, information integration center of the body, is mainly composed of neurons and glial cells. The neuron is one of the most basic and important structural and functional units of the central n... The central nervous system, information integration center of the body, is mainly composed of neurons and glial cells. The neuron is one of the most basic and important structural and functional units of the central nervous system, with sensory stimulation and excitation conduction functions. Astrocytes and microglia belong to the glial cell family, which is the main source of cytokines and represents the main defense system of the central nervous system. Nerve cells undergo neurotransmission or gliotransmission, which regulates neuronal activity via the ion channels, receptors, or transporters expressed on nerve cell membranes. Ion channels, composed of large transmembrane proteins, play crucial roles in maintaining nerve cell homeostasis. These channels are also important for control of the membrane potential and in the secretion of neurotransmitters. A variety of cellular functions and life activities, including functional regulation of the central nervous system, the generation and conduction of nerve excitation, the occurrence of receptor potential, heart pulsation, smooth muscle peristalsis, skeletal muscle contraction, and hormone secretion, are closely related to ion channels associated with passive transmembrane transport. Two types of ion channels in the central nervous system, potassium channels and calcium channels, are closely related to various neurological disorders, including Alzheimer's disease, Parkinson's disease, and epilepsy. Accordingly, various drugs that can affect these ion channels have been explored deeply to provide new directions for the treatment of these neurological disorders. In this review, we focus on the functions of potassium and calcium ion channels in different nerve cells and their involvement in neurological disorders such as Parkinson's disease, Alzheimer's disease, depression, epilepsy, autism, and rare disorders. We also describe several clinical drugs that target potassium or calcium channels in nerve cells and could be used to treat these disorders. We concluded that there are few clinical drugs that can improve the pathology these diseases by acting on potassium or calcium ions. Although a few novel ion-channelspecific modulators have been discovered, meaningful therapies have largely not yet been realized. The lack of target-specific drugs, their requirement to cross the blood–brain barrier, and their exact underlying mechanisms all need further attention. This review aims to explain the urgent problems that need research progress and provide comprehensive information aiming to arouse the research community's interest in the development of ion channel-targeting drugs and the identification of new therapeutic targets for that can increase the cure rate of nervous system diseases and reduce the occurrence of adverse reactions in other systems. 展开更多
关键词 ASTROCYTES calcium channels central nervous system extracellular ion concentration MICROGLIA neurological disorders NEURONS potassium channels
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A photon-photon collider based on synchrotron γ rays in hollow plasma channels
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作者 Yi-Nuo Liu Zhang-Hu Hu +3 位作者 Jie-Jie Lan Hao-Yuan Li Wang-Wen Xu You-Nian Wang 《Matter and Radiation at Extremes》 2025年第5期38-44,共7页
We propose a photon-photon collider based on synchrotron gamma sources driven by relativistic electron beams in hollow plasma channels.The collimated(with a divergence angle of~1 mrad)and ultrabrilliant(>10^(28)pho... We propose a photon-photon collider based on synchrotron gamma sources driven by relativistic electron beams in hollow plasma channels.The collimated(with a divergence angle of~1 mrad)and ultrabrilliant(>10^(28)photons s^(-1)·mrad^(-2)·mm^(-2)per 0.1% bandwidth at 0.6 MeV)photon beams are generated by strong electromagnetic fields induced by current filamentation instability,and up to~10^(6) Breit-Wheeler(BW)pairs can be created per shot.Notably,the usage of hollow plasma channels not only enhances synchrotron radiation,but also allows flexible control of the produced photon beams,ensuring the alignment of the two colliding beams and maximizing the two-photon BW process.This setup has the advantage of a clean background by eliminating the yield from the nonlinear BW process,and the signal-to-noise ratio is higher than 10^(2). 展开更多
关键词 synchrotron gamma sources relativistic electron beams strong electromagnetic fields hollow plasma channels synchrotron gamma rays hollow plasma channelsthe photon photon collider current filamentation instabilityand
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Irreversibility analysis and multiple cubic regression based efficiency evaluation of ternary nanofluids(TiO_(2)+SiO_(2)+Al_(2)O_(3)/H_(2)O and TiO_(2)+SiO_(2)+Cu/H_(2)O)via converging/diverging channels 被引量:1
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作者 Siddhant Taneja Sapna Sharma Bhuvaneshvar Kumar 《Acta Mechanica Sinica》 2025年第6期63-75,共13页
This study numerically examines the heat and mass transfer characteristics of two ternary nanofluids via converging and diverg-ing channels.Furthermore,the study aims to assess two ternary nanofluids combinations to d... This study numerically examines the heat and mass transfer characteristics of two ternary nanofluids via converging and diverg-ing channels.Furthermore,the study aims to assess two ternary nanofluids combinations to determine which configuration can provide better heat and mass transfer and lower entropy production,while ensuring cost efficiency.This work bridges the gap be-tween academic research and industrial feasibility by incorporating cost analysis,entropy generation,and thermal efficiency.To compare the velocity,temperature,and concentration profiles,we examine two ternary nanofluids,i.e.,TiO_(2)+SiO_(2)+Al_(2)O_(3)/H_(2)O and TiO_(2)+SiO_(2)+Cu/H_(2)O,while considering the shape of nanoparticles.The velocity slip and Soret/Dufour effects are taken into consideration.Furthermore,regression analysis for Nusselt and Sherwood numbers of the model is carried out.The Runge-Kutta fourth-order method with shooting technique is employed to acquire the numerical solution of the governed system of ordinary differential equations.The flow pattern attributes of ternary nanofluids are meticulously examined and simulated with the fluc-tuation of flow-dominating parameters.Additionally,the influence of these parameters is demonstrated in the flow,temperature,and concentration fields.For variation in Eckert and Dufour numbers,TiO_(2)+SiO_(2)+Al_(2)O_(3)/H_(2)O has a higher temperature than TiO_(2)+SiO_(2)+Cu/H_(2)O.The results obtained indicate that the ternary nanofluid TiO_(2)+SiO_(2)+Al_(2)O_(3)/H_(2)O has a higher heat transfer rate,lesser entropy generation,greater mass transfer rate,and lower cost than that of TiO_(2)+SiO_(2)+Cu/H_(2)O ternary nanofluid. 展开更多
关键词 Converging/Diverging channels Ternary nanofluids Multiple cubic regression Entropy generation
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Revenue increased by 370%,new channels for new domestic products:Taihu Snow
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作者 Qiu Shuchen 《China Textile》 2025年第4期40-43,共4页
Taihu Snow (838262) is a home textile manufacturing company listed on the Beijing Stock Exchange in 2022.It is a bedding manufacturer focusing on silk products.The company was esta blished on May 18,2006,Centered arou... Taihu Snow (838262) is a home textile manufacturing company listed on the Beijing Stock Exchange in 2022.It is a bedding manufacturer focusing on silk products.The company was esta blished on May 18,2006,Centered around the"Taihu Snow"brand,its products cover suite products (such as pillowcases,quilt covers,sheets),quilt cores,silk scarves and otheremerging retail products. 展开更多
关键词 NEW suite products such REVENUE channels domestic emerging retail productsit silk productsthe increase
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Intracellular calcium channels:Potential targets for type 2 diabetes mellitus?
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作者 Jia-Xuan Zhu Zhao-Nan Pan Dan Li 《World Journal of Diabetes》 2025年第4期37-47,共11页
Type 2 diabetes mellitus(T2DM)is a prevalent metabolic disorder.Despite the availability of numerous pharmacotherapies,a range of adverse reactions,including hypoglycemia,gastrointestinal discomfort,and lactic acidosi... Type 2 diabetes mellitus(T2DM)is a prevalent metabolic disorder.Despite the availability of numerous pharmacotherapies,a range of adverse reactions,including hypoglycemia,gastrointestinal discomfort,and lactic acidosis,limits their patient applicability and long-term application.Therefore,it is necessary to screen novel therapeutic drugs for T2DM treatment that have high efficacy but few adverse effects.AMP-activated protein kinase(AMPK)stands out as one of the most powerful targets for T2DM treatment.It can be activated through energysensing or calcium signaling.Medications that activate AMPK through the energy-sensing mechanism exhibit remarkable potency,but they are accompanied by lactic acidosis,carrying an alarmingly high mortality rate.Interestingly,medications that activate AMPK through calcium signaling,such as gliclazide,seldom induce lactic acidosis.However,the efficacy of gliclazide is much lower than metformin.Therefore,it is necessary to explore targets that activate AMPK via calcium signaling to avoid lactic acidosis while maintaining high potency.Ion channels are the main controller of intracellular calcium flow.Specific agonists and inhibitors targeting ion channels have been reported to activate AMPK.In this review,we will summarize the structure and function of calcium-permeable ion channels and discuss the potential of targeting these calcium channels for T2DM treatment. 展开更多
关键词 Ion channels AMP-activated protein kinase CALCIUM DIABETES Lactic acidosis
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Screening suitable metal ion bridges for the construction of unimpeded dual carrier-transfer channels in carbon nitride photocatalyst
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作者 Meixian Liu Shuyun Xue +2 位作者 Yajun Zhang Linjuan Pei Zhanfeng Zheng 《Chinese Journal of Chemical Engineering》 2025年第4期70-78,共9页
The huge carrier transfer resistance caused by large-sized"nitrogen pot"severely limits the photocatalytic performance of carbon nitride(CN).This study aims to explore the selection principle of metal ion br... The huge carrier transfer resistance caused by large-sized"nitrogen pot"severely limits the photocatalytic performance of carbon nitride(CN).This study aims to explore the selection principle of metal ion bridges for constructing dual carrier-transfer channels to delivery carriers to respectively active sites using photodegradation of phenol as the model reaction.Density functional theory(DFT)calculation was used to optimize the structure model of nitrogen vacancies(Nv,provide active sites for reduction of O_(2) and oxidation of phenol)and metal ions(Fe^(3+),Co^(2+),Ni^(2+)or Cu^(2+))co-modified CN,and screen metal ion bridges based on the three parameters including bonding state of metal ion and"nitrogen pot",electrostatic potential(ESP)distribution around the active sites,and three-electron bond length.Both calculation results and activity data show that Fe^(3+),Co^(2+)and Ni^(2+)can construct dual carrier-transfer channels to promote the degradation of phenol while Cu^(2+)cannot Ny and Fe^(3+)co-modified CN(Fe/N_(v)-CN)showed the best catalytic performance among various catalysts and was used as the model catalyst for the detailed characterization to verify the calculation results.This work provides not only the novel strategy for constructing dual carrier-transfer channels in CN,but also the crucial basis for computer simulation as a prediction tool of catalyst structure design rationality. 展开更多
关键词 Carbon nitride Dual carrier-transfer channels Metal ion bridges Degradation Computer simulation RADICAL
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A sediment influx-outflux-accommodation composite index-based method for estimating sediment storage in debris flow channels
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作者 LEI Xiaohu ZHANG Shaojie +1 位作者 YANG Hongjuan WEI Fangqiang 《Journal of Mountain Science》 2025年第6期1889-1911,共23页
The distribution of the sediment material storage quantity along the debris flow channels(SMSQ_DFC)can provide a foundation for runoffgenerated debris flow prediction or susceptibility assessment.Current models for es... The distribution of the sediment material storage quantity along the debris flow channels(SMSQ_DFC)can provide a foundation for runoffgenerated debris flow prediction or susceptibility assessment.Current models for estimating SMSQ_DFC do not consider the capacity of the channel cross-section to accommodate sediment materials.This accommodation condition serves as a limiting factor in determining whether the expected surplus of sediment materials can ultimately be stored.To address this issue,a mass-conservative index was used to represent the balance of deposit materials at any cross-section,considering the influx from upstream,outflux to downstream,and accommodation capacity.Based on this index,a new model for estimating SMSQ_DFC was developed and subsequently evaluated.The evaluation results show that the model meets the accuracy requirements with average error rates of 14.06%for self-validation and 14.81%for generalization ability validation.To assess its practical applications,the model was applied to the Yeniu Gully in Wenchuan County,Sichuan Province,an area with detailed field survey data.The results show that the model exhibits a commendable performance.Compared to traditional theoretical and semi-theoretical statistical models,our model is easier to use(input parameters can be obtained using Geographic Information Systems(GIS)).The modeling parameters chosen in this study have more theoretical significance than those used in existing purely statistical models,offering more effective technical support for estimating SMSQ_DFC. 展开更多
关键词 Debris flow deposit materials Sediment influx-outflux-accommodation index Sediment materials distribution along channels Deposit materials estimation model Channel bed deposits Debris flow provenance materials
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Vertical channels enable excellent lithium storage kinetics and cycling stability in silicon/carbon thick electrode
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作者 Wen Zhang Zihan Zhang +13 位作者 Xinxin Wang Wanming Li Qin Chen Wangting Zhong Junhong Wei Zihe Chen Shuibin Tu Xiancheng Wang Yuchen Tan Yun Zhang Huiqiao Li Yongming Sun Huamin Zhou Hui Yang 《Carbon Energy》 2025年第2期54-65,共12页
Constructing silicon(Si)-based composite electrodes that possess high energy density,long cycle life,and fast charging capability simultaneously is critical for the development of high performance lithium-ion batterie... Constructing silicon(Si)-based composite electrodes that possess high energy density,long cycle life,and fast charging capability simultaneously is critical for the development of high performance lithium-ion batteries for mitigating range anxiety and slow charging issues in new energy vehicles.Herein,a thick silicon/carbon composite electrode with vertically aligned channels in the thickness direction(VC-SC)is constructed by employing a bubble formation method.Both experimental characterizations and theoretical simulations confirm that the obtained vertical channel structure can effectively address the problem of sluggish ion transport caused by high tortuosity in conventional thick electrodes,conspicuously enhance reaction kinetics,reduce polarization and side reactions,mitigate stress,increase the utilization of active materials,and promote cycling stability of the thick electrode.Consequently,when paired with LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)(NCM622),the VC-SC||NCM622 pouch type full cell(~6.0 mAh cm^(-2))exhibits significantly improved rate performance and capacity retention compared with the SC||NCM622 full cell with the conventional silicon/carbon composite electrode without channels(SC)as the anode.The assembled VC-SC||NCM622 pouch full cell with a high energy density of 490.3 Wh kg^(-1)also reveals a remarkable fast charging capability at a high current density of 2.0 mA cm^(-2),with a capacity retention of 72.0%after 500 cycles. 展开更多
关键词 high transport kinetics silicon/carbon anode structural stability thick electrode vertical channels
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Total Variation Based Asymptotics of Covert Communication in AWGN Channels
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作者 Wang Jianquan Tang Wanbin Li Xiaoping 《China Communications》 2025年第5期173-188,共16页
Covert communication guarantees the security of wireless communications via hiding the existence of the transmission.This paper focuses on the first and second order asymptotics of covert communication in the AWGN cha... Covert communication guarantees the security of wireless communications via hiding the existence of the transmission.This paper focuses on the first and second order asymptotics of covert communication in the AWGN channels.The covertness is measured by the total variation distance between the channel output distributions induced with and without the transmission.We provide the exact expressions of the maximum amount of information that can be transmitted with the maximum error probability and the total variation less than any small numbers.The energy detection and the random coding are employed to prove our results.We further compare our results with those under relative entropy.The results show how many additional amounts of information can be transmitted covertly when changing the covertness constraint to total variation. 展开更多
关键词 additive white Gaussian noise channels asymptotical analysis covert communication relative entropy total variation
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RIS-Aided Secure Communications over Fisher-Snedecor F Fading Channels
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作者 Farshad Rostami Ghadi Zhu Weiping Diego Martin 《China Communications》 2025年第7期195-207,共13页
In this paper,we investigate the performance of physical layer security(PLS)over reconfigurable intelligent surfaces(RIS)-aided wireless communication systems,where all fading channels are modeled with Fisher-Snedecor... In this paper,we investigate the performance of physical layer security(PLS)over reconfigurable intelligent surfaces(RIS)-aided wireless communication systems,where all fading channels are modeled with Fisher-Snedecor F distribution.Specifically,we consider a RIS with N reflecting elements between the transmitter and the legitimate receiver to develop a smart environment and also meliorate secure communications.In this regard,we derive the closed-form expressions for the secrecy outage probability(SOP)and average secrecy capacity(ASC).We also analyze the asymptotic behaviour of the SOP and ASC by exploiting the residue approach.Monte-Carlo(MC)simulation results are provided throughout to validate the correctness of the developed analytical results,showing that considering RIS in wireless communication systems has constructive effects on the secrecy performance. 展开更多
关键词 average secrecy capacity Fisher-Snedecor F fading channels physical layer security reconfigurable intelligent surfaces secrecy outage probability
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Improving the performance of reference-frame-independent measurement-device-independent quantum key distribution in hybrid channels
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作者 Yan-Mei Zhao Chun Zhou +8 位作者 Xiao-Lei Jiang Yi-Fei Lu Yu Zhou Hai-Tao Wang Yang Wang Jia-Ji Li Yan-Yang Zhou Hong-Wei Li Wan-Su Bao 《Chinese Physics B》 2025年第5期26-32,共7页
The robustness of reference-frame-independent measurement-device-independent quantum key distribution(RFIMDI-QKD)against detection system vulnerabilities and its tolerance to reference frame drifts make it an ideal ch... The robustness of reference-frame-independent measurement-device-independent quantum key distribution(RFIMDI-QKD)against detection system vulnerabilities and its tolerance to reference frame drifts make it an ideal choice for hybrid channels.However,the impact of atmospheric turbulence on transmittance fluctuations remains a significant challenge for enhancing the performance of RFI-MDI-QKD.In this paper,we apply prefixed-threshold real-time selection and advantage distillation techniques to RFI-MDI-QKD in a hybrid channels scenario.Then,we analytically derive formulas for secret key rate in hybrid channels.Simulation results show that our modified scheme has apparent advances in both maximum tolerant loss and secure key rate compared to the fiber-only channel.Specifically,the result demonstrates that the maximum transmission distance can be improved by 15 km and 28 km when N=10^(12)and 10^(11).Our work not only provides a more robust key distribution protocol but also establishes a solid theoretical foundation for enhancing the performance of RFI-MDI-QKD in hybrid channels. 展开更多
关键词 quantum key distribution measurement-device-independent hybrid channels
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A Machine Learning-Based Channel Data Enhancement Platform for Digital Twin Channels
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作者 AI Bo ZHANG Yuxin +2 位作者 YANG Mi HE Ruisi GUO Rongge 《ZTE Communications》 2025年第2期20-30,共11页
Reliable channel data helps characterize the limitations and performance boundaries of communication technologies accurately.However,channel measurement is highly costly and time-consuming,and taking actual measuremen... Reliable channel data helps characterize the limitations and performance boundaries of communication technologies accurately.However,channel measurement is highly costly and time-consuming,and taking actual measurement as the only channel data source may reduce efficiency because of the constraints of high testing difficulty and limited data volume.Although existing standard channel models can generate channel data,their authenticity and diversity cannot be guaranteed.To address this,we use deep learning methods to learn the attributes of limited measured data and propose a generative model based on generative adversarial networks to rapidly synthesize data.A software simulation platform is also established to verify that the proposed model can generate data that are statistically similar to the measured data while maintaining necessary randomness.The proposed algorithm and platform can be applied to channel data enhancement and serve channel modeling and algorithm evaluation applications with urgent needs for data. 展开更多
关键词 channel measurement channel modeling deep learning data enhancement
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Confined electric field in nano-sized channels of ionic porous framework towards unique adsorption selectivity
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作者 Congyan Liu Xueyao Zhou +2 位作者 Fei Ye Bin Jiang Bo Liu 《Chinese Chemical Letters》 2025年第2期437-441,共5页
Efficient selective adsorption and separation using porous frameworks are critical in many industrial processes,where adsorption energy and dynamic diffusion rate are predominant factors governing selectivity.They are... Efficient selective adsorption and separation using porous frameworks are critical in many industrial processes,where adsorption energy and dynamic diffusion rate are predominant factors governing selectivity.They are highly susceptible to framework charge,which plays a significant role in selective adsorption.Currently,ionic porous frameworks can be divided into two types.One of them is composed of a charged backbone and counter ions.The framework with zwitterionic channels is another type.It is composed of regular and alternating arrangements of cationic and anionic building units.Herein,we report a hydrogen-bonded ionic framework(HIF)of{(CN_(3)H_(6))_(2)[Ti(μ_(2)-O)(SO_(4))_(2)]}_nwith 1D channel exhibits unique adsorption selectivity for Ar against N_(2)and CO_(2).Density functional theory(DFT)results suggest that CO_(2)cannot be adsorbed by HIF at the experimental temperature due to a positive adsorption free energy.In addition,due to a relatively large diffusion barrier at 77 K,N_(2)molecules hardly diffuse in HIF channels,while Ar has a negligible diffusion barrier.The unique net positively-charged space in the channel is the key to the unusual phenomena,based on DFT simulations and structural analysis.The findings in this work proposes the new adsorption mechanism and provides unique perspective for special separation applications,such as isotope and noble gasses separations. 展开更多
关键词 Adsorption SELECTIVITY Channel Positive electric field GUANIDINIUM
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Discovery of E0199:A novel compound targeting both peripheral Na_(V)and K_(V)7 channels to alleviate neuropathic pain
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作者 Boxuan Zhang Xiaoxing Shi +12 位作者 Xingang Liu Yan Liu Xuedong Li Qi Wang Dongyang Huang Weidong Zhao Junru Cui Yawen Cao Xu Chai Jiahao Wang Yang Zhang Xiangyu Wang Qingzhong Jia 《Journal of Pharmaceutical Analysis》 2025年第1期244-261,共18页
This research study focuses on addressing the limitations of current neuropathic pain(NP)treatments by developing a novel dual-target modulator,E0199,targeting both Na_(V)1.7,Na_(V)1.8,and Na_(V)1.9 and K_(V)7 channel... This research study focuses on addressing the limitations of current neuropathic pain(NP)treatments by developing a novel dual-target modulator,E0199,targeting both Na_(V)1.7,Na_(V)1.8,and Na_(V)1.9 and K_(V)7 channels,a crucial regulator in controlling NP symptoms.The objective of the study was to synthesize a compound capable of modulating these channels to alleviate NP.Through an experimental design involving both in vitro and in vivo methods,E0199 was tested for its efficacy on ion channels and its therapeutic potential in a chronic constriction injury(CCI)mouse model.The results demonstrated that E0199 significantly inhibited Na_(V)1.7,Na_(V)1.8,and Na_(V)1.9 channels with a particularly low half maximal inhibitory concentration(IC50)for Na_(V)1.9 by promoting sodium channel inactivation,and also effectively increased K_(V)7.2/7.3,K_(V)7.2,and K_(V)7.5 channels,excluding K_(V)7.1 by promoting potassium channel activation.This dual action significantly reduced the excitability of dorsal root ganglion neurons and alleviated pain hypersensitivity in mice at low doses,indicating a potent analgesic effect without affecting heart and skeletal muscle ion channels critically.The safety of E0199 was supported by neurobehavioral evaluations.Conclusively,E0199 represents a ground-breaking approach in NP treatment,showcasing the potential of dual-target small-molecule compounds in providing a more effective and safe therapeutic option for NP.This study introduces a promising direction for the future development of NP therapeutics. 展开更多
关键词 Neuropathic pain Na_(V)channel K_(V)7 channel Dorsal root ganglia
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Far-Field vs. Near-Field Propagation Channels: Key Differences and Impact on 6G XL-MIMO Performance Evaluation
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作者 Ding Zihang Zhang Jianhua +5 位作者 You Changsheng Tang Pan Xing Hongbo Yuan Zhiqiang Meng Jie Liu Guangyi 《China Communications》 2025年第10期186-198,共13页
Extremely large-scale multiple-input multiple-output(XL-MIMO)is regarded as a promis-ing technology for next-generation communication systems.However,this will expand the near-field(NF)range,rendering more users more ... Extremely large-scale multiple-input multiple-output(XL-MIMO)is regarded as a promis-ing technology for next-generation communication systems.However,this will expand the near-field(NF)range,rendering more users more likely to be located in the NF region.In this paper,we aim to answer two questions:What are the new characteristics of the NF channel?Is it necessary to develop new transciver techniques to maintain system performance within the NF region?To this end,we first review current NF channel models and analyze the differences between the existing 3GPP TR 38.901 channel model and the NF channel model,including the spherical wavefront and spatially non-stationarity.Then,we provide ex-amples on how these differences affect the XL-MIMO system performance in terms of beamforming gain and achievable rate.Simulation results demonstrate that,when using far-field(FF)technique under the NF channel,the maximum normalized beam gain loss is less than 3 dB for most users in the NF region de-fined by Rayleigh distance.Moreover,the achievable rate loss of beam training is less than 3%compared to that realized by NF technique.Finally,we demonstrate the necessity of employing NF transceiver techniques based on simulation results. 展开更多
关键词 channel model near-field communica-tion near-field effect spatial non-stationary
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Design and Optimization of Converging-Diverging Liquid Cooling Channels for Enhanced ThermalManagement in Lithium-ion Battery Packs
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作者 Tianjiao Zhang YiboXu +2 位作者 LongLi KequnLi Hua Zhang 《Frontiers in Heat and Mass Transfer》 2025年第3期819-832,共14页
Power batteries serve as key components of new energy vehicles and are distinguished by their large capacity,long lifespan,high energy density,and stable operation.The strict temperature demands of power battery packs... Power batteries serve as key components of new energy vehicles and are distinguished by their large capacity,long lifespan,high energy density,and stable operation.The strict temperature demands of power battery packs necessitate the development of highly efficient thermal management systems.In this study,a converging-diverging liquid cooling channel featuring a wave shaped structure was designed and analyzed for 18,650-type lithium-ion batteries.To investigate the design methodology for flow channel structure,a thermal model for the heat generation rate of the 18,650-type battery was developed.A comparative analysis of four geometrical configurations of convergingdiverging channels.It identified the flat-bottomed channel achieves a maximum reduction of 20.6%in peak internal temperature compared to the other designs.Subsequently,the effects of the arc depth,cell spacing,and Reynolds number on the heat dissipation of the flat-bottomed flow channel were comprehensively investigated.The results demonstrated that increasing the Reynolds number,maximizing the arc depth of the converging-diverging structure,and reducing cell spacing considerably improved the cooling heat dissipation efficiency.Based on the particle swarm optimization algorithm,the optimal parameter combination of the battery pack was obtained at a discharge rate of 2C,comprising an arc depth of 8.5 mm,cell spacing of 1 mm,and Reynolds number of 700.The study provides valuable guidance and references for the practical design and implementation of thermal management systems in new energy vehicles. 展开更多
关键词 Thermal management system converging-diverging flow channel heat dissipation performance BATTERY particle swarm optimization
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Thermal radiation impact on hybrid nanocomposite flow in stretchable channels:a Darcy-Forchheimer model with the Taylor wavelet approach
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作者 B.J.GIREESHA K.J.GOWTHAM 《Applied Mathematics and Mechanics(English Edition)》 2025年第6期1107-1124,共18页
The study of stretching surfaces has garnered significant attention due to its importance in a wide range of industrial and engineering functions,including the drawing of wires and plastic films,shrink film production... The study of stretching surfaces has garnered significant attention due to its importance in a wide range of industrial and engineering functions,including the drawing of wires and plastic films,shrink film production,polymer sheet extrusion,the manufacturing of glass fibers,and the manufacturing of polyester heat-shrink tubing.This research incorporates a Darcy-Forchheimer porous medium to account for the effects of porosity.The governing equations are transformed into a boundary value problem and solved semi-analytically using the Taylor wavelet method.The effects of various parameters are depicted through graphical analyses.The results show that for both converging and diverging stretching surfaces,an increase in the porosity parameter causes a decrease in the velocity field.Additionally,higher Reynolds numbers enhance inertial effects,leading to more pronounced velocity fluctuations.Stretching causes a consistent drop in velocity toward the center and an increase close to the walls in both types of channels,indicating that the volume percentage of nanoparticles influences the heat distribution.Notably,stretching induces a marked temperature drop at the channel's center. 展开更多
关键词 Darcy-Forchheimer flow stretching wall porous medium convergent and divergent channel
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Spectral Efficiency of Cell-Free Massive MIMO with LSFD Receiver Under Spatially Correlated Rayleigh Fading Channels
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作者 Li Ning Fan Pingzhi 《China Communications》 2025年第8期1-18,共18页
This paper investigates the uplink spectral efficiency of distributed cell-free(CF)massive multiple-input multiple-output(mMIMO)networks with correlated Rayleigh fading channels based on three different channel estima... This paper investigates the uplink spectral efficiency of distributed cell-free(CF)massive multiple-input multiple-output(mMIMO)networks with correlated Rayleigh fading channels based on three different channel estimation schemes.Specifically,each access point(AP)first uses embedded pilots to estimate the channels of all users based on minimum mean-squared error(MMSE)estimation.Given the high computational cost of MMSE estimation,the low-complexity element-wise MMSE(EW-MMSE)channel estimator and the least-squares(LS)channel estimator without prior statistical information are also analyzed.To reduce non-coherent and coherent interference during uplink payload data transmission,simple centralized decoding(SCD)and large-scale fading decoding(LSFD)are examined.Then,the closedform expressions for uplink spectral efficiency(SE)using MMSE,EW-MMSE,and LS estimators are developed for maximum ratio(MR)combining under LSFD,where each AP may have any number of antennas.The sum SE maximization problem with uplink power control is formulated.Since the maximization problem is non-convex and challenging,a block coordinate descent approach based on the weighted MMSE method is used to get the optimal local solution.Numerical studies demonstrate that LSFD and efficient uplink power control can considerably increase SE in distributed CF m MIMO networks. 展开更多
关键词 CF mMIMO channel estimation largescale fading decoding simple centralized decoding sum SE optimization
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Construction of Polar Codes in Correlated Block Fading Channels via Split Polar Spectrum
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作者 Li Yan Niu Kai 《China Communications》 2025年第10期137-148,共12页
The construction of polar codes in corre-lated block fading channels is still an open issue to be solved.In this paper,to explicitly reveal the impact of correlation on error performance of polar coded diver-sity comm... The construction of polar codes in corre-lated block fading channels is still an open issue to be solved.In this paper,to explicitly reveal the impact of correlation on error performance of polar coded diver-sity communication systems,an integrated framework has been established to analyze the theoretical error performance of polar codes in correlated block fading channels.First,the upper bound on error probabil-ity of polarized channels is derived based on split po-lar spectrum,which is fully determined by covariance channel matrix as well as the block-wise weight distri-bution of the corresponding polar subcode.Further,to facilitate practical implementations,we design a con-struction metric named polarized correlation weight(PCW)to generate polar codes in correlated block fad-ing channels.Finally,simulation results on block error rate indicate that the proposed metric can exhibit both diversity gain and coding gain compared to the con-ventional methods under successive cancellation de-coding. 展开更多
关键词 CONSTRUCTION correlated block Rayleigh fading channel polar codes split polar spectrum
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