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Dynamic balance and reliability of a stochastic ecosystem with Markov switching
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作者 Ya-Nan Sun Xin-Zhi Liu You-Ming Lei 《Chinese Physics B》 2026年第1期381-390,共10页
A stochastic predator-prey system with Markov switching is explored.We have developed a new chasing technique to efficiently solve the Fokker-Planck-Kolmogorov and backward Kolmogorov equations.Dynamic balance and rel... A stochastic predator-prey system with Markov switching is explored.We have developed a new chasing technique to efficiently solve the Fokker-Planck-Kolmogorov and backward Kolmogorov equations.Dynamic balance and reliability of the switching system are evaluated via stationary probability density function and first-passage failure theory,taking into account factors such as switching frequencies,noise intensities,and initial conditions.Results reveal that Markov switching leads to stochastic P-bifurcation,enhancing dynamic balance and reducing white-noise-induced oscillations.But frequent switching can heighten initial value dependence,harming reliability.Further,the influence of the subsystem on the switching system is not proportional to its action probabilities.Monte Carlo simulations validate the findings,offering an in-depth exploration of these dynamics. 展开更多
关键词 stochastic ecosystem Markov switching first-passage failure RELIABILITY
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Leader-following positive consensus of heterogeneous switched multi-agent systems with average dwell time switching
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作者 Kaiming Li Wei Xing +1 位作者 Haoyue Yang Junfeng Zhang 《Control Theory and Technology》 2026年第1期66-81,共16页
This paper focuses on the leader-following positive consensus problems of heterogeneous switched multi-agent systems.First,a state-feedback controller with dynamic compensation is introduced to achieve positive consen... This paper focuses on the leader-following positive consensus problems of heterogeneous switched multi-agent systems.First,a state-feedback controller with dynamic compensation is introduced to achieve positive consensus under average dwell time switching.Then sufficient conditions are derived to guarantee the positive consensus.The gain matrices of the control protocol are described using a matrix decomposition approach and the corresponding computational complexity is reduced by resorting to linear programming and co-positive Lyapunov functions.Finally,two numerical examples are provided to illustrate the results obtained. 展开更多
关键词 Heterogeneous switched multi-agent systems Positive consensus Linear programming
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Balancing switching and transient response for ion gating in field-effect nanofluidic transistors
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作者 Xiaoqing Wu Yajie Chen +3 位作者 Dagui Wang Song Pu Qiujiao Du Pengcheng Gao 《Chinese Chemical Letters》 2026年第1期385-388,共4页
Field-effect nanofluidic transistors(FENTs),biomimicking the structure and functionality of neuron,act as biological transistors with the ability to gate switching responses to external stimuli.The switching ratio has... Field-effect nanofluidic transistors(FENTs),biomimicking the structure and functionality of neuron,act as biological transistors with the ability to gate switching responses to external stimuli.The switching ratio has been verified to evaluate the performance of FENTs,but until recently,the response time,another crucial indicator,has been ignored.Employing finite-element method,we investigated the relationship among gate charge,switching ratio and response time by divisionally manipulating gate charge,including entrance surface and the surface of confinement space,for ion transport to optimize switching capability.The dual-split gate charge on FENTs exhibits synergistic effect on switching response.Based on the two regional gate charge on FENTs,multivalence ions in lower concentration,high aspect ratio and single channel show higher switching ratio but longer response time compared to monovalent ions.The findings highlight the necessity of balancing these two signals in FENTs and offer insights for optimizing their design and expanding applications to dual-signal-detection iontronics. 展开更多
关键词 Nanofluidic transistor Gate charge Ion transport switching ratio Response time
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The Grammatical Constraints on Code-switching in Fortress Besieged
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作者 李洁 王士齐 张慧 《科技信息》 2010年第30期I0147-I0148,共2页
This paper analyzes the grammatical structures of code-switching in Qian Zhongshu 's famous work-Fortress Besieged and two conclusions are reached: In this novel, the matrix language Chinese plays a dominant role ... This paper analyzes the grammatical structures of code-switching in Qian Zhongshu 's famous work-Fortress Besieged and two conclusions are reached: In this novel, the matrix language Chinese plays a dominant role in the mixed constituents, lexically, morphologically and syntactically while in the matrix language islands and the embedded language islands, constituents respectively follow the grammatical rules of the matrix language-Chinese and the embedded language-English or French. 展开更多
关键词 英语学习 学习动机 学习方法 英语阅读
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A Study of Code-Switching in Students' Talk in College English Class
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作者 席红梅 赵快 《海外英语》 2015年第4期133-134,共2页
Code-switching between English and Chinese usually occurs in students' talk when they are involved in taking communicative language activities in college English class. This paper studies the situations in which s... Code-switching between English and Chinese usually occurs in students' talk when they are involved in taking communicative language activities in college English class. This paper studies the situations in which students are likely to use codeswitching and analyzes it from the perspective of the mental world in Verscheren's Adaptation Theory. It shows that inadequate mastery of English language, cultural differences and the improper adjustment to context may lead to students' using of codeswitching. It also shows that the use of code-switching in students' talk adapts to students' cognitive elements and emotive elements as well. 展开更多
关键词 STUDENTS TALK code-switching ADAPTATION THEORY
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Code-Switching and Second Ianguage Acquisition
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作者 罗茜 《21世纪(理论实践探索)》 2010年第6期123-124,共2页
关键词 第二语言 学习方法 创新 创造性活动
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Relevance theory: the Cognitive Pragmatic Foundation of Code-switching
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作者 令狐曼 《科教导刊》 2015年第9期153-154,共2页
The paper will discuss the process of code-switching and its cognitive pragmatic motivation from the point of relevance.And code-switching is also regarded as a kind of communicative strategy.The process of the produc... The paper will discuss the process of code-switching and its cognitive pragmatic motivation from the point of relevance.And code-switching is also regarded as a kind of communicative strategy.The process of the production of code-switching is also the cooperation and mutual constrain of communicator’s cognitive environment and ability.Cognitive effect can be obtained through communicator’s processing cognitive environment with their cognitive ability.In this process,the cooperation of cognitive ability and cognitive environment gives a guarantee to successful communication with code-switching. 展开更多
关键词 RELEVANCE theory COGNITIVE CONTEXT code-switching
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A Study on the Teachers'Code-switching in Vocational College Non-Eng lish Majors'English Instruction
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作者 黄晶晶 《海外英语》 2012年第22期70-71,91,共3页
This paper is designed to investigate the teachers'code-switching used in English instruction in vocational colleges and wants to make some efforts to the better understanding and use of code-switching and develop... This paper is designed to investigate the teachers'code-switching used in English instruction in vocational colleges and wants to make some efforts to the better understanding and use of code-switching and develop a positive attitude towards the code-switching in English teaching classroom. 展开更多
关键词 code-switching ENGLISH INSTRUCTION language used i
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The Use of Code-switching in English Foreign Language Classroom
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作者 徐婷 《海外英语》 2018年第16期228-230,共3页
people used to be negative on the use of code-switching in English foreign language classroom.However,more and moreresearches begin to argue that code-switching does have its practical significance.Some basic concepts... people used to be negative on the use of code-switching in English foreign language classroom.However,more and moreresearches begin to argue that code-switching does have its practical significance.Some basic concepts of code-switching will first-ly be introduced in the article.Then,there is a literature review of the previous studies on the code-switching in English foreignlanguage class.By exposing detailed researches on it,some implications for teaching pedagogy will be explicated.From differentperspectives of the use of code-switching,this article aims to explore the necessity of code-switching in a context of foreign lan-guage teaching classroom by presenting some latest researches on it and reviewing different views on the use of code-switching inEnglish Foreign Language class. 展开更多
关键词 code-switching English foreign language class REVIEW PEDAGOGY
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Electropolymerized dopamine-based memristors using threshold switching behaviors for artificial current-activated spiking neurons 被引量:1
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作者 Bowen Zhong Xiaokun Qin +4 位作者 Zhexin Li Yiqiang Zheng Lingchen Liu Zheng Lou Lili Wang 《Journal of Semiconductors》 2025年第2期98-103,共6页
Memristors have a synapse-like two-terminal structure and electrical properties,which are widely used in the construc-tion of artificial synapses.However,compared to inorganic materials,organic materials are rarely us... Memristors have a synapse-like two-terminal structure and electrical properties,which are widely used in the construc-tion of artificial synapses.However,compared to inorganic materials,organic materials are rarely used for artificial spiking synapses due to their relatively poor memrisitve performance.Here,for the first time,we present an organic memristor based on an electropolymerized dopamine-based memristive layer.This polydopamine-based memristor demonstrates the improve-ments in key performance,including a low threshold voltage of 0.3 V,a thin thickness of 16 nm,and a high parasitic capaci-tance of about 1μF·mm^(-2).By leveraging these properties in combination with its stable threshold switching behavior,we con-struct a capacitor-free and low-power artificial spiking neuron capable of outputting the oscillation voltage,whose spiking fre-quency increases with the increase of current stimulation analogous to a biological neuron.The experimental results indicate that our artificial spiking neuron holds potential for applications in neuromorphic computing and systems. 展开更多
关键词 ELECTROPOLYMERIZATION POLYDOPAMINE MEMRISTOR threshold switching spiking voltage artificial neuron
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Periodic Event-Triggered Consensus of Stochastic Multiagent Systems Under Switching Topology 被引量:1
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作者 Boqian LI Linhao ZHAO Shiping WEN 《Artificial Intelligence Science and Engineering》 2025年第2期147-156,共10页
The event-triggered mechanism serves as an effective discontinuous control strategy for addressing the consensus tracking problem in multiagent systems(MASs).This approach optimizes energy consumption by updating the ... The event-triggered mechanism serves as an effective discontinuous control strategy for addressing the consensus tracking problem in multiagent systems(MASs).This approach optimizes energy consumption by updating the controller only when some observed errors exceed a predefined threshold.Considering the influence of noise on agent dynamics in complex control environments,this study investigates an event-triggered control scheme for stochastic MASs,where noise is modeled as Brownian motion.Furthermore,the communication topology of the stochastic MASs is assumed to exhibit a Markovian switching mechanism.Analytical criteria are derived to guarantee consensus tracking in the mean square sense,and a numerical example is provided to validate the effectiveness of the proposed control methods. 展开更多
关键词 cooperative control stochastic systems event-triggered mechanism switching topology
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Neural correlates of attentional switching dysfunction in major depressive disorder:Evidence from an event-related potential study with a dual-task paradigm 被引量:1
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作者 Ya-Wen Wu Xin-Yu Wang +7 位作者 Yi-Fan Sun Luo-An Wu Wei Li Yu Li Xue-Zheng Gao Xiao-Hong Liu Zhen-He Zhou Hong-Liang Zhou 《World Journal of Psychiatry》 2025年第12期90-106,共17页
BACKGROUND Research has consistently demonstrated that patients with major depressive disorder(MDD)exhibit attentional switching dysfunction,and the dual-task paradigm has emerged as a valuable tool for probing cognit... BACKGROUND Research has consistently demonstrated that patients with major depressive disorder(MDD)exhibit attentional switching dysfunction,and the dual-task paradigm has emerged as a valuable tool for probing cognitive deficits.However,the neuroelectrophysiological mechanism underlying this deficit has not been clarified.AIM To investigate the event-related potential(ERP)characteristics of attentional switching dysfunction and further explore the neuroelectrophysiological mechanism of the cognitive processing deficits underlying attentional switching dysfunction in MDD.METHODS The participants included 29 MDD patients and 29 healthy controls(HCs).The ERPs of the participants were measured while they performed the dual-task para digm.The behavioral and ERP N100,P200,P300,and late positive potential(LPP)data were analyzed.RESULTS This study revealed greater accuracy in HCs and slower reaction times(RTs)in MDD patients.Angry facial pictures led to lower accuracy.The results also revealed shorter RTs for happy facial pictures and the longest RTs for the 500-ms stimulus onset asynchrony.With respect to ERP characteristics,happy facial pictures and neutral facial pictures evoked higher amplitudes.The N100,P200,P300,and LPP amplitudes at Pz were the highest.MDD patients had lower P200 mean amplitudes and LPP amplitudes than HCs did.CONCLUSION In conclusion,MDD patients exhibited abnormal ERP characteristics evoked by the dual-task paradigm,which could be the neural correlates of the known abnormalities in attentional switching in patients with MDD.These results provide valuable insights into the understanding of the neural mechanisms of attentional switching function and may guide targeted interventions in patients with MDD. 展开更多
关键词 Major depressive disorder Attentional switching function Dual-task paradigm Event-related potential COGNITION
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Smooth switching mechanism-based adaptive integral terminal SMC for PMSM servo system with stator voltage saturation and unknown disturbances 被引量:1
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作者 Xiangxiang Meng Haisheng Yu +1 位作者 Jie Zhang Qing Yang 《Control Theory and Technology》 2025年第2期294-309,共16页
This article investigates the anti-disturbance and stabilization problems for the nonlinear uncertain permanent magnet synchronous motor(PMSM)with stator voltage saturation and unknown load.A smooth switching mechanis... This article investigates the anti-disturbance and stabilization problems for the nonlinear uncertain permanent magnet synchronous motor(PMSM)with stator voltage saturation and unknown load.A smooth switching mechanism is presented to structure the adaptive integral terminal sliding mode control(SMC)strategy.The control design consists of compensation control and nominal control,which improves the rapidity and accuracy of trajectory tracking.The smooth saturation model based on the error function is applied to approximate the voltage saturation phenomenon.Additionally,to deal with the adverse effects of various unknown disturbances,including model parameter uncertainties and unknown external load disturbances,an improved disturbance observer(DO)is proposed.This observer effectively suppresses the fluctuations caused by fixed gain during the starting period of the system.Finally,the experimental results under different conditions show that the proposed strategy has good tracking and disturbance suppression performances. 展开更多
关键词 Smooth switching mechanism Integral terminal SMC PMSM servo system Disturbance suppression Stator voltage saturation
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A Study of EFL Teachers' code-switching in Vocational College Intensive Reading Classroom
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作者 程亚玲 《海外英语》 2013年第24期264-265,267,共3页
In the past 30 years, code-switching has been a focus in the field of linguistics in western countries. Researchers stud?ied it from different angles and have made a lot of findings.However, the researchers in China b... In the past 30 years, code-switching has been a focus in the field of linguistics in western countries. Researchers stud?ied it from different angles and have made a lot of findings.However, the researchers in China begin their studies on this issue un?til the last decade. Thus,the relevent empirical studies were less and most of them only use students from the classrooms in the sec?ondary schools or the undergraduates in the universities as the subjects.They paid little attention to the EFL classrooms in the vo?cational colleges. Vocational college students are poor in English foundation. English teachers can not finish their teaching mission in English classroom, so the use of code-switching becomes a very common phenomenon in EFL class of vocational college. In order to make teaching and learning promote and enhance each other, according to previous research findings, this paper do a fur?ther study about the teachers' use of code switching in the vocational college English intensive reading classes in China. 展开更多
关键词 code-switching Jef Verschueren’s THEORY Yu Guodong
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Enhanced memory window and efficient resistive switching in stabilized BaTiO_(3)-based RRAM through incorporation of Al_(2)O_(3) interlayer 被引量:1
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作者 Akendra Singh Chabungbam Minjae Kim +2 位作者 Atul Thakre Dong-eun Kim Hyung-Ho Park 《Journal of Materials Science & Technology》 2025年第10期125-134,共10页
As artificial intelligence and big data become increasingly prevalent, resistive random-access memory (RRAM) has become one of the most promising alternatives for storing massive amounts of data. In this study, we emp... As artificial intelligence and big data become increasingly prevalent, resistive random-access memory (RRAM) has become one of the most promising alternatives for storing massive amounts of data. In this study, we employed high-quality crystalline TiN/Al_(2)O_(3)/BaTiO_(3)/Pt RRAM with an optimized thin Al_(2)O_(3) interlayer around 12 nm thick prepared using atomic layer deposition since the thickness of the interlayer affects the memory window size. After insertion of the Al_(2)O_(3) interlayer, the novel RRAM exhibited outstanding uniform resistive switching voltage and the ON/OFF memory window drastically increased from 10 to 103 without any discernible decline in performance. Moreover, the low-resistance state and high-resistance state operating current values decreased by almost one order and three orders of magnitude, respectively, thereby decreasing the power consumption for the RESET and SET processes by more than three and almost one order of magnitude, respectively. The device also exhibits multilevel resistive switching behavior when varying the applied voltage. Finally, we also developed a 6 6 crossbar array which demonstrated consistent and reliable resistive switching behavior with minimal variation. Hence, our approach holds great promise for producing state-of-the-art non-volatile resistive switching devices. 展开更多
关键词 Resistive random-access memory Resistive switching Atomic layer deposition Al_(2)O_(3)interlayer
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Grid-Connected/Islanded Switching Control Strategy for Photovoltaic Storage Hybrid Inverters Based on Modified Chimpanzee Optimization Algorithm
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作者 Chao Zhou Narisu Wang +1 位作者 Fuyin Ni Wenchao Zhang 《Energy Engineering》 EI 2025年第1期265-284,共20页
Uneven power distribution,transient voltage,and frequency deviations are observed in the photovoltaic storage hybrid inverter during the switching between grid-connected and island modes.In response to these issues,th... Uneven power distribution,transient voltage,and frequency deviations are observed in the photovoltaic storage hybrid inverter during the switching between grid-connected and island modes.In response to these issues,this paper proposes a grid-connected/island switching control strategy for photovoltaic storage hybrid inverters based on the modified chimpanzee optimization algorithm.The proposed strategy incorporates coupling compensation and power differentiation elements based on the traditional droop control.Then,it combines the angular frequency and voltage amplitude adjustments provided by the phase-locked loop-free pre-synchronization control strategy.Precise pre-synchronization is achieved by regulating the virtual current to zero and aligning the photovoltaic storage hybrid inverter with the grid voltage.Additionally,two novel operators,learning and emotional behaviors are introduced to enhance the optimization precision of the chimpanzee algorithm.These operators ensure high-precision and high-reliability optimization of the droop control parameters for photovoltaic storage hybrid inverters.A Simulink model was constructed for simulation analysis,which validated the optimized control strategy’s ability to evenly distribute power under load transients.This strategy effectively mitigated transient voltage and current surges during mode transitions.Consequently,seamless and efficient switching between gridconnected and island modes was achieved for the photovoltaic storage hybrid inverter.The enhanced energy utilization efficiency,in turn,offers robust technical support for grid stability. 展开更多
关键词 Photovoltaic storage hybrid inverters modified chimpanzee optimization algorithm droop control seamless switching
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Time-Varying Formation Tracking Control of Heterogeneous Multi-Agent Systems With Intermittent Communications and Directed Switching Networks
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作者 Yuhan Wang Zhuping Wang +1 位作者 Hao Zhang Huaicheng Yan 《IEEE/CAA Journal of Automatica Sinica》 2025年第1期294-296,共3页
Dear Editor,This letter is concerned with the problem of time-varying formation tracking for heterogeneous multi-agent systems(MASs) under directed switching networks. For this purpose, our first step is to present so... Dear Editor,This letter is concerned with the problem of time-varying formation tracking for heterogeneous multi-agent systems(MASs) under directed switching networks. For this purpose, our first step is to present some sufficient conditions for the exponential stability of a particular category of switched systems. 展开更多
关键词 switched systems time varying formation tracking directed switching networks heterogeneous multi agent systems intermittent communications exponential stability
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Dual-responsive Flexible Dielectric Switching Composites for Overheating Warning and Small Deformation Monitoring
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作者 Chuan-Yu Jiang Hai-Rong Li +6 位作者 Yu Peng Liu-Yang Zhang Wu-Hou Fan Luo-Xin Wang Ming Jiang Zi-Qing Cai Li-Jie Dong 《Chinese Journal of Polymer Science》 2025年第10期1885-1893,共9页
The phenomena of thermal runaway and accidental deformation due to external stresses in lithium batteries or film capacitors consti-tute their primary failure mechanisms.Therefore,monitoring and early warning of overh... The phenomena of thermal runaway and accidental deformation due to external stresses in lithium batteries or film capacitors consti-tute their primary failure mechanisms.Therefore,monitoring and early warning of overheating or localized strain are of great value for the safe use of lithium batteries or film capacitors;however,this function usually requires a system of multiple complex sensors.The realization of the above multiple hazards using a single sensor for monitoring and alarm functions has not been reported.Here,we exploit the thermally induced conductivity and modulus change during solid-liquid conversion of low melting point polyalloys to modulate the electronic relaxation polariza-tion and interfacial polarization in the composites for dielectric switching,and the reduction of alloy particle spacing during bending/compres-sive strain can be used to generate switchable tunneling effects for insulator-conductor transition.By synergizing dielectric switching and insula-tor-conductor transition,the final flexible thermoplastic polyurethane elastomer/low-melting-point polyalloy composite film achieves the func-tional integration of multi-level overheating warning and small deformation monitoring. 展开更多
关键词 Dielectric switching Insulator-conductor transition Polarization OVERHEATING DEFORMATION
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SOX6 enhances vascular smooth muscle cell phenotypic switching and elevates blood pressure by activating autophagy
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作者 Qianhui Ling Xilan Dong +5 位作者 Liyan Mao Chengjun Huang Linjing Cong Haizeng Zhang Jun Cai Zhenzhen Chen 《Animal Models and Experimental Medicine》 2025年第8期1400-1415,共16页
Background : SOX6 has been shown to play a crucial role in the development of the cardiovascular system. However, its potential role in hypertension and vascular function remains unclear. Methods : In vascular smooth ... Background : SOX6 has been shown to play a crucial role in the development of the cardiovascular system. However, its potential role in hypertension and vascular function remains unclear. Methods : In vascular smooth muscle cells(VSMCs), we employed gain-and loss-offunction approaches combined with RNA sequencing, autophagy flux assessment, and phenotype characterization. Additionally, we established a mouse model with Sox6 overexpression via adeno-associated virus 2(AAV2) to validate the findings in vivo. Results : We validated the increased expression of SOX6 in hypertension both in vitro and in vivo. Genetic silencing of Sox6 in VSMCs attenuated the phenotypic switching induced by angiotensin Ⅱ. Conversely, in vivo overexpression of Sox6 led to a significant elevation in blood pressure and promoted vascular remodeling. Mechanistically, SOX6 was shown to regulate phenotypic switching via an autophagydependent pathway. Specifically, Sox6 overexpression augmented VSMC autophagy and facilitated phenotypic switching, whereas Sox6 knockdown yielded opposite outcomes. Modulation of autophagy using 3-MA or RAPA could effectively counteract the effect mediated by SOX6. Conclusions : Our findings revealed that SOX6 regulates VSMC plasticity and elevates blood pressure by activating autophagy. Therefore, SOX6 inhibition potentially represents a novel strategy for treating hypertension and vascular remodeling. 展开更多
关键词 AUTOPHAGY HYPERTENSION SOX6 VSMC phenotypic switching
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Research on adaptive smooth switching control strategy for strong and weak power grids in multi-machine parallel PV energy storage VSG system
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作者 Zuobin Zhu Shumin Sun Yueming Ding 《Global Energy Interconnection》 2025年第5期790-803,共14页
To enable distributed PV to adapt to variations in power grid strength and achieve stable grid connection while enhancing operational flexibility,it is essential to configure grid-connected inverters with an integrate... To enable distributed PV to adapt to variations in power grid strength and achieve stable grid connection while enhancing operational flexibility,it is essential to configure grid-connected inverters with an integrated grid-following control mode,allowing smooth switching between GFL and GFM modes.First,impedance models of GFL and GFM PV energy storage VSG systems were established,and grid stability was analyzed.Second,an online impedance identification method based on voltage fluctuation data screening was proposed to enhance the accuracy of impedance identification.Additionally,a PV energy storage GFM/GFL VSG smooth switching method based on current inner loop compensation was introduced to achieve stable grid-connected operation of distributed photovoltaics under changes in strong and weak power grids.Finally,a grid stability analysis was conducted on the multi-machine parallel PV ESS,and a simulation model of a multi-machine parallel PV ESS based on current inner loop compensation was established for testing.Results showed that,compared to using a single GFM or single GFL control for the PV VSG system,the smooth switching method of multi-machine parallel PV ESS effectively suppresses system resonance under variations in power grid strength,enabling adaptive and stable grid-connected operations of distributed PV. 展开更多
关键词 PV GFM VSG GFL VSG RESONANCE Smooth switching
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