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A muon high-resolution pseudorange measurement method: Application to muon navigation in confined spaces

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Chinese Journal of Aeronautics 2024年第4期37卷 391-404页

作者： Haoyang LI Chunxi ZHANG Xingming fan Longjie tian tianqi LI Yang PANG Yanqiang YANG Institute of Optics and Electronics School of Instrumentation Science and Optoelectronics EngineeringBeihang UniversityBeijing 100191China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China

Confined spaces such as polar regions, deep earth and deep ocean are crucial navigation scenarios where traditional navigation techniques have difficulty in obtaining external signals for positioning. The cosmic ray muons, which carry the spatial and energetic information, are easy to penetrate these confined spaces. Therefore, the unique muon characteristic provides a new perspective to estimate detector position, which can be considered using in confined spaces *** this paper, a well-developed theory of muon navigation is established by combining a muon pseudorange measurement method. Moreover, an Equivalent Velocity Calculation Model(EVCM)and a Muon Sequence Matching Technology(MSMT) are proposed. The first model corrects flight pseudorange error caused by the relativistic energy loss and the second technology compensates the random error in pseudorange measurement. Further, a series of simulations are performed to analyze the muon events number which can be received by detector in different scenarios with the variations of zenith angle, detector area, varied detector plates gap, and muon flight ***, the simulation results demonstrate that the muon navigation update rate every 10 minutes can reach 5.989 in confined spaces at 100 m, and further pseudorange error analysis indicates that the meter-level positioning accuracy can be acquired. Finally, we construct a muon coincidence measurement scheme and verify that the laws of the muon positioning system for high-energy muons are consistent with the simulation results.

关键词： Muon navigation Cosmic ray muons Muon detection technology Muon transmission technology Pseudorange measurement

Micro/nanoelectrode-based electrochemical methodology for single cell and organelle analysis

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Nano Research 2024年第1期17卷 196-206页

作者： Chuchu Xu De Yang Yuchan Wang Ruolin Liu fan Wang Zhongqun tian Keke Hu Department of Chemistry College of Chemistry&Chemical EngineeringXiamen UniversityXiamen 361005China

Cells are the basic unit of *** analysis of single cells/organelles is essential for uncovering the molecular mechanisms of physiological and pathological processes that are difficult to elucidate on a larger *** paper provides an overview of the commonly used fabrication methods for micro/nanoelectrodes applied in the investigations of single cells/organelles as well as the corresponding electrochemical measurements over the last four years including extracellular measurement,combination of extra and intracellular measurement,intracellular reactive oxygen species and reactive nitrogen species(ROS/RNS)measurement,and isolated organelles measurement.

关键词： single cell/organelle micro/nanoelectrode electrochemical measurement chemical transmitters

Multicomponent Seismic Data Reconstruction via Anti-Aliasing Vector POCS Method

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Journal of Earth Science 2024年第4期35卷 1385-1392页

作者： fan Li Jianjun Gao yun Wang Chunming Wang Sian Hou School of Geophysics and Information Technology China University of GeosciencesBeijing 100083China Research Institute of Petroleum Exploration and Development Petro ChinaBeijing 100083China

0 INTRODUCTION Due to the ability to comprehensively utilize P and S wave information,multi-component seismic exploration has already played an important role in fracture detection,lithology prediction,fluid identification,etc.,and it has also become an important technology for complex reservoir exploration(Yuan et al.,2021;Stewart et al.,2003).

关键词： reservoir Seismic prediction

Cell metabolism pathways involved in the pathophysiological changes of diabetic peripheral neuropathy

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Neural Regeneration Research 2024年第3期19卷 598-605页

作者： Yaowei Lv Xiangyun Yao Xiao Li Yuanming Ouyang Cunyi fan yun Qian Department of Orthopedics Shanghai Sixth People’s Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghaiChina Shanghai Engineering Research Center for Orthopaedic Material Innovation and Tissue Regeneration ShanghaiChina Youth Science and Technology Innovation Studio of Shanghai Jiao Tong University School of Medicine ShanghaiChina College of Fisheries and Life Science Shanghai Ocean UniversityShanghaiChina

Diabetic peripheral neuropathy is a common complication of diabetes *** the pathophysiological metabolic mechanism impels the generation of ideal ***,existing limited treatments for diabetic peripheral neuropathy expose the urgent need for cell metabolism *** the lack of comprehensive understanding of energy metabolism changes and related signaling pathways in diabetic peripheral neuropathy,it is essential to explore energy changes and metabolic changes in diabetic peripheral neuropathy to develop suitable treatment *** review summarizes the pathophysiological mechanism of diabetic peripheral neuropathy from the perspective of cellular metabolism and the specific interventions for different metabolic pathways to develop effective treatment *** metabolic mechanisms(e.g.,polyol,hexosamine,protein kinase C pathway)are associated with diabetic peripheral neuropathy,and researchers are looking for more effective treatments through these pathways.

关键词： cell metabolism diabetic peripheral neuropathy peripheral nerve injury protein kinase C pathway reactive oxygen species.

Synergistic Ru/RuO_(2) heterojunctions stabilized by carbon coating as efficient and stable bifunctional electrocatalysts for acidic overall water splitting

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Nano Research 2024年第8期17卷 6931-6939页

作者： Man Wu Yuying fan Yang Huang Dongxu Wang Ying Xie Aiping Wu Chungui tian Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education of the People’s Republic of ChinaHeilongjiang UniversityHarbin 150080China

The development of highly active and stable acidic water oxidation electrocatalysts is of great significant for promoting the industrial application of proton exchange membrane ***-based catalysts have broad application prospects in acidic water oxidation,but their limitations in stability and activity hinder their further ***,a nitrogen-doped carbon(NC)coated porous Ru/RuO_(2) heterojunctional hollow sphere(Ru/RuO_(2)/NC)is designed as high-active and stable bifunctional electrocatalyst for acidic oxygen evolution reaction(OER)and hydrogen evolution reaction(HER).In synthesis,the key is to use mesoporous polydopamine spheres as a template for forming hollow spheres,a source of NC coating and a reducing agent for forming Ru/RuO_(2) *** Ru/RuO_(2) heterojunction adjusts the electronic structure of Ru active sites,optimizing the adsorption of intermediate ***,the NC coating and the interaction between NC and Ru/RuO_(2) effectively prevent Ru from over-oxidation and *** porous hollow structure provides more exposed active sites and promotes mass ***,Ru/RuO_(2)/NC exhibits outstanding OER and HER performance with low overpotentials of 211 and 32 mV at 10 mA·cm^(−2),respectively,and shows excellent *** acid water splitting electrolyzer,based on the bifunctional Ru/RuO_(2)/NC,requires low cell voltages of 1.46 and 1.76 V at 10 and 100 mA·cm^(−2),respectively,with good stability for over 100 h operation,surpassing Pt/C||RuO_(2) and most of the reported catalysts.

关键词： hollow heterojunction bifunctional electrocatalysts oxygen evolution hydrogen evolution acidic water splitting

A survey on model-based reinforcement learning

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Science China(Information Sciences) 2024年第2期67卷 59-84页

作者： fan-Ming LUO tian XU Hang LAI Xiong-Hui CHEN Weinan ZHANG Yang YU National Key Laboratory for Novel Software Technology Nanjing University Polixir. ai Department of Computer Science and Engineering Shanghai Jiao Tong University

Reinforcement learning(RL) interacts with the environment to solve sequential decision-making problems via a trial-and-error approach. Errors are always undesirable in real-world applications, even though RL excels at playing complex video games that permit several trial-and-error attempts. To improve sample efficiency and thus reduce errors, model-based reinforcement learning(MBRL) is believed to be a promising direction, as it constructs environment models in which trial-and-errors can occur without incurring actual costs. In this survey, we investigate MBRL with a particular focus on the recent advancements in deep RL. There is a generalization error between the learned model of a non-tabular environment and the actual environment. Consequently, it is crucial to analyze the disparity between policy training in the environment model and that in the actual environment, guiding algorithm design for improved model learning, model utilization, and policy training. In addition, we discuss the recent developments of model-based techniques in other forms of RL, such as offline RL, goal-conditioned RL, multi-agent RL, and meta-RL. Furthermore,we discuss the applicability and benefits of MBRL for real-world tasks. Finally, this survey concludes with a discussion of the promising future development prospects for MBRL. We believe that MBRL has great unrealized potential and benefits in real-world applications, and we hope this survey will encourage additional research on MBRL.

关键词： reinforcement learning model-based reinforcement learning planning model learning model learning with reduced error model usage

Sex-specific strategies of resource utilization and determining mechanisms of Hippophae rhamnoides in response to community succession

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Journal of Plant Ecology 2024年第4期17卷 114-130页

作者： Baoli fan Pengfei Gao Tingting tian Nana Ding Yongkuan Wan Xianhui Zhou College of Life Science Northwest Normal UniversityLanzhou 730000China Key Laboratory of Eco-functional Polymer Materials of the Ministry of Education Lanzhou 730000China College of Ecology Lanzhou UniversityLanzhou 730000China

The dioecious plant,Hippophae rhamnoides,is a pioneer species in community succession on the Qinghai-Tibet Plateau(QTP),plays great roles in various ecosystem ***,the males and females of the species differ both in their morphology and physiology,resulting in a change in the ratio of male to female plants depending on the *** further explore the functional traits critical to this sex-based distinctive response in the alpine grassland,we have surveyed the sex ratios,measured their photosynthetic parameters,height,leaf area and biomass *** results showed that(i)The males had higher Pn,light saturation point,apparent quantum efficiency,A_(max) and lower water-use efficiency(WUE),which exhibited higher utilization efficiency or tolerance to strong light,while the females indicated higher utilization efficiency for low light and *** it showed sex-specific biomass allocation patterns.(ii)*** populations across the successional stages all showed a male-biased sexual allocation,which was closely related to sex-specific WUE,Pn,root biomass/total biomass and root-crown ratio.(iii)The leaf traits of *** changed from higher N_(area),P_(area) and leaf mass per area in the early and late to lower in the middle,which meant they moved their growth strategy from resource rapid acquisition to conservation as the succession progressed.(iv)The increasing soil total phosphorus mostly contributed to regulating the sex bias of populations and variations of traits during the *** results are vital for the management of grassland degradation and restoration due to shrub encroachment on the QTP.

关键词： dioecious sex ratio shrub encroachment functional traits physiological and ecological strategies

Low-carbon development policies and achievements in the context of the livestock sector in China

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Frontiers of Agricultural Science and Engineering 2024年第3期11卷 367-380页

作者： Sha WEI Junming fan Yanfeng tian Hongmin DONG Institute of Environmental and Sustainable Development in Agriculture Chinese Academy of Agriculture SciencesBeijing 100081China Inner Mongolia YouRan Dairy Co. Ltd.Hohhot 010070China

Rapid growth and a vast transition of Chinese livestock industry driven by economic incentives make it become an important contributor on climate change over the last four *** study first analyzes the evolving lowcarbon livestock development policies and regulations,then an assessment and explanations of the achievements and non-achievements are *** findings reveal that China began to pay attention to low-carbon development policy starting in the early ***,only after the cyclic and green concept became the main sustainable development policy,China began to move seriously toward low-carbon livestock *** policy instruments were introduced,including moderate scale,feed optimization,manure resource utilization,facility and equipment allocation rate,energy conservation and ***,achievements were made in introducing such ***,due to the large share of standard agriculture and regional resources,and environmental diversity,such policies may have little effect in *** divergence between the policies and actual practices are explained,and important policies applicable to all developing countries are also recommended.

关键词： Low carbon livestock development policy recommendations divergence carbon market

Development of SV2A Ligands for Epilepsy Treatment:A Review of Levetiracetam,Brivaracetam,and Padsevonil

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Neuroscience Bulletin 2024年第5期40卷 594-608页

作者： Peng-Peng Wu Bi-Rong Cao Fu-yun tian Zhao-Bing Gao Center for Neurological and Psychiatric Research and Drug Discovery Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai201203China University of Chinese Academy of Sciences Beijing100049China Zhongshan Institute for Drug Discovery Shanghai Institute of Materia MedicaChinese Academy of SciencesZhongshan528400China

Epilepsy is a common neurological disorder that is primarily treated with antiseizure medications(ASMs).Although dozens of ASMs are available in the clinic,approximately 30%of epileptic patients have medically refractory seizures;other limitations in most traditional ASMs include poor tolerability and drug-drug ***,there is an urgent need to develop alternative ***(LEV)is a first-line ASM that is well tolerated,has promising efficacy,and has little drug-drug *** it is widely accepted that LEV acts through a unique therapeutic target synaptic vesicle protein(SV)2A,the molecular basis of its action remains *** so,the next-generation SV2A ligands against epilepsy based on the structure of LEV have achieved clinical *** review highlights the research and development(R&D)process of LEV and its analogs,brivaracetam and padsevonil,to provide ideas and experience for the R&D of novel ASMs.

关键词： Levetiracetam Epilepsy Antiseizure medications Synaptic vesicle protein 2A Brivaracetam Padsevonil