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An actor-critic based learning method for decision-making and planning of autonomous vehicles

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Science China(Technological Sciences) 2021年第5期64卷 984-994页

作者： XU can zhao WanZhong CHEN QingYun WANG ChunYan Department of Vehicle Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

In order to improve the agility and applicability of trajectory planning algorithm for autonomous vehicles, this paper proposes a novel actor-critic based learning method for decision-making and planning in multi-vehicle complex traffic. It is the coupling planning of vehicle’s path and speed thus to make the trajectory more flexible. First, generations from the decided action to the planned trajectory are described by the end-point of the trajectory. Then, the actor-critic based learning method is built to learn an optimal policy for the decision process. It can update the policy by the gradient of the current policy’s advantage. In this process,features of the real traffic are carefully extracted by time headway(TH) and speed distribution. Reward function is built by the safety, efficiency and driving comfort. Furthermore, to make the policy network have better convergency, the policy network is modularized in two parts: the lane-changing network and the lane-keeping network, which decide the optimal end-point of the path and speed candidates respectively. Finally, the curved overtaking scenario and the interaction process with human driver are conducted to illustrate the feasibility and superiority. The results show that the proposed method has better real-time performance and can make the planned coupling trajectory more continuous and smoother than the existing rule-based method.

关键词： trajectory planning decision-making actor-critic feature extraction autonomous driving

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Salsolinol as an RNA m~6A methylation inducer mediates dopaminergic neuronal death by regulating YAP1 and autophagy

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Neural Regeneration Research 2025年第3期20卷 887-899页

作者： Jianan Wang Yuanyuan Ran Zihan Li Tianyuan zhao Fangfang Zhang Juan Wang Zongjian Liu Xuechai Chen Beijing International Science and Technology Cooperation Base for Antiviral Drugs College of Chemistry and LifeBeijing University of TechnologyBeijingChina Department of Rehabilitation Beijing Rehabilitation HospitalCapital Medical UniversityBeijingChina

Salsolinol(1-methyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline,Sal)is a catechol isoquinoline that causes neurotoxicity and shares structural similarity with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine,an environmental toxin that causes Parkinson's ***,the mechanism by which Sal mediates dopaminergic neuronal death remains *** this study,we found that Sal significantly enhanced the global level of N~6-methyladenosine(m~6A)RNA methylation in PC12 cells,mainly by inducing the downregulation of the expression of m~6A demethylases fat mass and obesity-associated protein(FTO)and alk B homolog 5(ALKBH5).RNA sequencing analysis showed that Sal downregulated the Hippo signaling *** m~6A reader YTH domain-containing family protein 2(YTHDF2)promoted the degradation of m~6A-containing Yes-associated protein 1(YAP1)mRNA,which is a downstream key effector in the Hippo signaling ***,downregulation of YAP1 promoted autophagy,indicating that the mutual regulation between YAP1 and autophagy can lead to *** findings reveal the role of Sal on m~6A RNA methylation and suggest that Sal may act as an RNA methylation inducer mediating dopaminergic neuronal death through YAP1 and *** results provide greater insights into the neurotoxic effects of catechol isoquinolines compared with other studies and may be a reference for assessing the involvement of RNA methylation in the pathogenesis of Parkinson's disease.

关键词： ALKBH5 autophagy FTO Hippo pathway m~6A Parkinson's disease RNA methylation salsolinol YAP1 YTHDF2

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MXene Hybridized Polymer with Enhanced Electromagnetic Energy Harvest for Sensitized Microwave Actuation and Self‑Powered Motion Sensing

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Nano-Micro Letters 2025年第3期17卷 265-279页

作者： Yu‑Ze Wang Yu‑Chang Wang Ting‑Ting Liu Quan‑Liang zhao Chen‑Sha Li Mao‑Sheng Cao School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081People’s Republic of China School of Materials Science and Engineering Peking UniversityBeijing 100871People’s Republic of China School of Mechanical and Material Engineering North China University of TechnologyBeijing 100144People’s Republic of China Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education of the People’s Republic of ChinaHeilongjiang UniversityHarbin 150080People’s Republic of China

Polymeric microwave actuators combining tissue-like softness with programmablemicrowave-responsive deformation hold great promise for mobile intelligentdevices and bionic soft robots. However, their application is challenged by restricted electromagneticsensitivity and intricate sensing coupling. In this study, a sensitized polymericmicrowave actuator is fabricated by hybridizing a liquid crystal polymer with Ti3C2Tx(MXene). Compared to the initial counterpart, the hybrid polymer exhibits unique spacechargepolarization and interfacial polarization, resulting in significant improvements of230% in the dielectric loss factor and 830% in the apparent efficiency of electromagneticenergy harvest. The sensitized microwave actuation demonstrates as the shortenedresponse time of nearly 10 s, which is merely 13% of that for the initial shape memory polymer. Moreover, the ultra-low content of MXene (upto 0.15 wt%) benefits for maintaining the actuation potential of the hybrid polymer. An innovative self-powered sensing prototype that combinesdriving and piezoelectric polymers is developed, which generates real-time electric potential feedback (open-circuit potential of ~ 3 mV) duringactuation. The polarization-dominant energy conversion mechanism observed in the MXene-polymer hybrid structure furnishes a new approachfor developing efficient electromagnetic dissipative structures and shows potential for advancing polymeric electromagnetic intelligent devices.

关键词： Microwave absorption Electromagnetic response Energy harvest Self-sensing Soft actuator

Multifunctional Nacre‑Like Nanocomposite Papers for Electromagnetic Interference Shielding via Heterocyclic Aramid/MXene Template‑Assisted In‑Situ Polypyrrole Assembly

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Nano-Micro Letters 2025年第3期17卷 37-54页

作者： Jinhua Xiong Xu zhao Zonglin Liu He Chen Qian Yan Huanxin Lian Yunxiang Chen Qingyu Peng Xiaodong He National Key Laboratory of Science and Technology On Advanced Composites in Special Environments Center for Composite Materials and StructuresHarbin Institute of TechnologyHarbin 150080People’s Republic of China

Robust, ultra-flexible, and multifunctional MXene-basedelectromagnetic interference (EMI) shielding nanocomposite filmsexhibit enormous potential for applications in artificial intelligence,wireless telecommunication, and portable/wearable electronic *** this work, a nacre-inspired multifunctional heterocyclic aramid(HA)/MXene@polypyrrole (PPy) (HMP) nanocomposite paper withlarge-scale, high strength, super toughness, and excellent tolerance tocomplex conditions is fabricated through the strategy of HA/MXenehydrogel template-assisted in-situ assembly of PPy. Benefiting from the"brick-and-mortar" layered structure and the strong hydrogen-bondinginteractions among MXene, HA, and PPy, the paper exhibits remarkable mechanical performances, including high tensile strength (309.7 MPa),outstanding toughness (57.6 MJ m−3), exceptional foldability, and structural stability against ultrasonication. By using the template effect ofHA/MXene to guide the assembly of conductive polymers, the synthesized paper obtains excellent electronic conductivity. More importantly,the highly continuous conductive path enables the nanocomposite paper to achieve a splendid EMI shielding effectiveness (EMI SE) of 54.1 dBat an ultra-thin thickness (25.4 μm) and a high specific EMI SE of 17,204.7 dB cm2g−1. In addition, the papers also have excellent applicationsin electromagnetic protection, electro-/photothermal de-icing, thermal therapy, and fire safety. These findings broaden the ideas for developinghigh-performance and multifunctional MXene-based films with enormous application potential in EMI shielding and thermal management.

关键词： MXene Remarkable mechanical properties Heterocyclic aramid Electromagnetic interference shielding Polypyrrole Multifunctionality

A review on applications of heuristic optimization algorithms for optimal power flow in modern power systems

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Journal of Modern Power Systems and Clean Energy 2014年第4期2卷 289-297页

作者： Ming NIU can WAN zhao XU The hong Kong Polytechnic University Hong KongChina

Optimal power flow(OPF)is one of the key tools for optimal operation and planning of modern power *** to the high complexity with continuous and discrete control variables,modern heuristic optimization algorithms(HOAs)have been widely employed for the solution of *** paper provides an overview of the latest applications of advanced HOAs in OPF *** most frequently applied HOAs for solving the OPF problem in recent years are covered and briefly introduced,including genetic algorithm(GA),differential evolution(DE),particle swarm optimization(PSO),and evolutionary programming(EP),etc.

关键词： Heuristic optimization algorithm Optimal power flow Multi-objective optimization Constraint optimization

Resolving the developmental mechanisms of cardiac microthrombosis of SARS-CoV-2 based on single-cell transcriptome analysis

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Science China Life Sciences 2025年第1期 103-115页

作者： Xizi Luo Nan Zhang Yuntao Liu Beibei Du Xuan Wang Tianxu zhao Bingqiang Liu Shishun zhao Jiazhang Qiu Guoqing Wang State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases Key Laboratory for Zoonosis Research of the Ministry of EducationCollege of Basic MedicineJilin University State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases Key Laboratory for Zoonosis Research of the Ministry of EducationCollege of Veterinary MedicineJilin University College of Mathematics Jilin University Bioinformatic Lab School of MathematicsShandong University Department of Cardiology China-Japan Union HospitalJilin University

The coronavirus disease 2019（COVID-19） outbreak caused by the severe acute respiratory syndrome coronavirus-2（SARS-CoV-2） developed into a global health emergency. Systemic microthrombus caused by SARS-CoV-2 infection is a common complication in patients with COVID-19. Cardiac microthrombosis as a complication of SARS-CoV-2 infection is the primary cause of cardiac injury and death in patietns with severe COVID-19. In this study, we performed single-cell sequencing analysis of the right ventricular free wall tissue from healthy donors,patients who died during the hypercoagulable period of characteristic coagulation abnormality（CAC）, and patients who died during the fibrinolytic period of CAC. We collected 61,187 cells enriched in 24 immune cell subsets and 13 cardiac-resident cell subsets. We found that in the course of SARS-CoV-2 infected heart microthrombus, MYO1EhighRASGEF1Bhighmonocyte-derived macrophages promoted hyperactivation of the immune system and initiated the extrinsic coagulation pathway by activating chemokines CCL3, CCL5. This series of events is the main cause of cardiac microthrombi following SARS-CoV-2 infection. In a SARS-CoV-2 infected heart microthrombus, excessive immune activation is accompanied by an increase in cellular iron content, which in turn promotes oxidative stress and intensifies intercellular competition. This induces cells to alter their metabolic environment, resulting in increased sugar uptake via the glycosaminoglycan synthesis pathway. In addition, high levels of reactive oxygen species generated by elevated iron levels promote increased endogenous malondialdehyde synthesis in a subpopulation of cardiac endothelial cells. This exacerbates endothelial cell dysfunction and exacerbates the coagulopathy process.

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Impact Toughness of an NM400 Wear-Resistant Steel

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Journal of Iron and Steel Research International 2013年第8期20卷 72-77页

作者： SONG hong-yu LI can-ming LAN Liang-yun zhao De-wen WANG Guo-dong State Key Laboratory of Rolling and Automation Northeastern University Laiwu Iron and Steel Group Co. Ltd.

An NM400 wear-resistant steel was hot rolled and then the plates were heat-treated by direct quenching and tempering （DQT） and reheat quenching and tempering （RQT） techniques, respectively. The Charpy impact test was carried out with an instrumented Charpy impact tester. The microstructure and fracture surface were investiga-ted by a combination of optical microscopy, transmission electron microscopy and scanning electron microscopy methods. It was found that the impact toughness of DQT specimen was much higher than that of RQT specimen. The microstructure of both DQT and RQT specimens was characterized by a mixture of tempered lath martensite and lower hainite. The lower bainite in DQT specimen extended into prior austenite grains and the content was higher than that in RQT specimen. The lower bainite in DOT specimen improved the impact toughness by increasing the proportion of large-angle boundaries and relieving the stress concentration at the crack tip. A number of fine and dis-persed carbides in DQT specimen also contributed to the improvement of the impact toughness.

关键词： impact toughness direct quenching tempering lower bainite martensite packet

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Spatial resolution improved OFDM-BOTDA utilizing frequency-division-multiplexed Brillouin phase/gain spectrum

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Science China(Information Sciences) 2021年第12期64卷 254-255页

作者： can zhao Hao WU Ming TANG Wuhan National Laboratory for Optoelectronics (WNLO) & National Engineering Laboratory for Next Generation Internet Access System School of Optical and Electronic InformationHuazhong University of Science and Technology

Dear editor,In the up-to-date dynamic measurement occasion, the traditional BOTDA(Brillouin optical time-domain analysis)measurement method of point-by-point frequency sweep fundamentally limits the measurement effici... 详细信息

关键词： Information Systems and Communication Service

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Erosion characteristics and mechanism of the self-resonating cavitating jet impacting aluminum specimens under the confining pressure conditions

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Journal of Hydrodynamics 2020年第2期32卷 375-384页

作者： Hua-lin Liao Sheng-li zhao Yan-feng Cao Lei Zhang can Yi Ji-lei Niu Li-hong Zhu School of Petroleum Engineering China University of PetroleumQingdao266580China State Key Laboratory of Offshore Oil Exploitation Beijing100028China Huanghe Drilling Co. Shengli Engineering Co.SINOPECDongying257000China Orion Energy International Co. LtdBeijing100101China

In order to study the effects of the confining pressure on the erosion characteristics of the self-resonating cavitating jet under wellbore and deep-water conditions,experiments are conducted on aluminum specimens impinged by the organ pipe cavitation nozzle and the conical nozzle with the confining pressure in the range 0 MPa–10.0 ***,through the numerical simulation of the collapsing process of the cavitation bubble and the noise test,the cavitation erosion mechanism is *** experimental results show that the optimal standoff distance and the confining pressure can be obtained for the maximum erosion quantities,and the optimal standoff distance is 5 to 7 times greater than the equivalent nozzle outlet diameter and the confining pressure is about 2.0 *** the same conditions,the erosion caused by the cavitation nozzle is up to 2 times larger than that caused by the conical *** to the numerical simulation and the noise test,the cavitation erosion on the aluminum specimens is mostly caused by mechanical forces due to the high-frequency pressure pulse generated during the collapse of cavitation bubbles,while just a small part is caused by micro-jets.

关键词： Cavitating jet cavitation erosion confining pressure nozzle