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Topological Tail Pressure for Asymptotically Sub-additive Continuous Potentials

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Communications in Mathematical Research 2017年第4期33卷 327-339页

作者： DING DAN-DAN MA XIAN-FENG chen er-cai Lei Feng-chun Department of Mathematics East China University of Science and Technology School of Mathematical Science Nanjing Normal University Center of Nonlinear Science Nanjing University

We define the topological tail pressure and the conditional pressure for asymptotically sub-additive continuous potentials on topological dynamical systems and obtain a variational principle for the topological tail p... 详细信息

关键词： asymptotically sub-additive potential tail pressure entropy structure variational principle

A New Treatment of Depression for Drainage Network Extraction Based on DEM

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Journal of Mountain Science 2009年第4期6卷 311-319页

作者： WANG Yan PENG Hong CUI Peng ZHANG Wanshun QIAO Fei chen cai'er School of Resource and Environmental Science Wuhan University Wuhan 430079 China College of Water Resources and Hydropower Engineering Wuhan University Wuhan 430072 China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China Chinese Academy of Environmental Sciences Beijing 100012 China

Depressions in landscapes function as buffers for water and sediment. A landscape with depressions has less runoff, less erosion and more sedimentation than that without depressions. Sinks in digital elevation models （DEMs） can be considered the real features that represent depressions in actual landscapes or spurious features that result from errors in DEM creation. In many hydrological and erosion models, all sinks are considered as spurious features and, as a result, these models do not deal with the sinks that represent real depressions. Consequently, the surface runoff and erosion are overestimated due to removing the depressions. Aiming at this problem, this paper presents a new method, which deal with the sinks that represent real depressions. The drainage network is extracted without changing the original DEM. The method includes four steps： detecting pits, detecting depressions, merging depressions, and extracting drainage network. Because the elevations of grid cells are not changed, the method can also avoid producing new fiat areas, which are always produced by the conventional filling methods. The proposed method was applied to the Xihanshui River basin, the upper reach of the Jialingjiang River basin, China, to automatically extract the drainage network based on DEM. The extracted drainage network agrees well with the reality and can be used for further hydrologic analysis and erosion estimation.

关键词： Drainage network extraction Depression processing Digital elevation model Wooden barrel effect Xihanshui River basin.

Upper Estimates on the Higher-dimensional Multifractal Spectrum of Local Entropy

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Northeastern Mathematical Journal 2008年第6期24卷 471-484页

作者：严珍珍陈二才 School of Mathematics and Physics Nanjing University of Posts and Nanjing 210003 School of Mathematics and Computer Science Nanjing Normal University Nanjing 210097

We discuss the problem of higher-dimensional multifractal spectrum of local entropy for arbitrary invariant measures. By utilizing characteristics of a dynamical system, namely, higher-dimensional entropy capacities and higher-dimensional correlation entropies, we obtain three upper estimates on the hlgher-dimensional multifractal spectrum of local entropies. We also study the domain of higher-dimensional multifractai spetrum of entropies.

关键词： multifractai analysis topological entropy entropy doubling condition entropy capacity correlation entropy

A knowledge-inherited learning for intelligent metasurface design and assembly

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Light(Science & Applications) 2023年第4期12卷 680-690页

作者： Yuetian Jia Chao Qian Zhixiang Fan Tong cai er-Ping Li Hongsheng chen ZJU-UIUC Institute Interdisciplinary Center for Quantum InformationState Key Laboratory of Extreme Photonics and InstrumentationZhejiang UniversityHangzhou 310027China ZJU-Hangzhou Global Science and Technology Innovation Center Key Lab.of Advanced Micro/Nano Electronic Devices&Smart Systems of ZhejiangZhejiang UniversityHangzhou 310027China Jinhua Institute of Zhejiang University Zhejiang UniversityJinhua 321099China Air and Missile Defense College Air Force Engineering UniversityXi'an 710051China Shaoxing Institute of Zhejiang University zhejiang UniversityShaoxing321000China

Recent breakthroughs in deep learning have ushered in an essential tool for optics and photonics,recurring in various applications of material design,system optimization,and automation *** learning-enabled on-demand metasurface design has been the subject of extensive expansion,as it can alleviate the time-consuming,low-efficiency,and experience-orientated shortcomings in conventional numerical simulations and physics-based ***,collecting samples and training neural networks are fundamentally confined to predefined individual metamaterials and tend to fail for large problem *** by object-oriented C++programming,we propose a knowledge-inherited paradigm for multi-object and shape-unbound metasurface inverse *** inherited neural network carries knowledge from the"parent"metasurface and then is freely assembled to construct the"offspring"metasurface;such a process is as simple as building a container-type *** benchmark the paradigm by the free design of aperiodic and periodic metasurfaces,with accuracies that reach 86.7%.Furthermore,we present an intelligent origami metasurface to facilitate compatible and lightweight satellite communication *** work opens up a new avenue for automatic metasurface design and leverages the assemblability to broaden the adaptability of intelligent metadevices.

关键词： breakthrough consuming shortcomings

Relative Entropy and Mean Li-Yorke Chaos Along Some Good Sequences

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Acta Mathematica Sinica,English Series 2021年第12期37卷 1947-1954页

作者： Pei WANG er cai chen Xiu Xiu LIU Xiao Yao ZHOU Basic Teaching Department Nanjing University Jinling CollegeNanjing 210089P.R.China School of Mathematical Sciences and Institute of Mathematics Nanjing Normal UniversityNanjing 210023P.R.China

In this article,we showed that positive relative entropy implies mean Li-Yorke chaos along some good sequences in the *** result extended Li and Qiao’s result in[***.,186(2018),153-173].

关键词： Relative entropy mean Li-Yorke chaos fiber relative Pinskerσ-algebra

Role of the Greenland Sea ice anomaly in the late-spring drought over Northwest China

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 1-5页

作者： Yang Liu Huopo chen Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of SciencesBeijingChina Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University for Information Science and TechnologyNanjingChina

Drought across Northwest China in late spring has exerted a vital effect on the local climate and agricultural production,and has been alleviated during the past *** study explored the influence of the preceding Arctic sea ice on the May drought in Northwest China caused by the precipitation *** analysis indicated that when the Greenland Sea ice concentration is abnormally high during February to April,the dry conditions in Northwest China tend to be *** increase of sea ice in the Greenland Sea can excite a meridional circulation,which causes sea surface temperature(SST)anomalies in the North Atlantic via the sea-air interaction,manifested as significant warm SST anomalies over the south of Greenland and the subtropical North Atlantic,but negative SST anomalies over the west of the *** abnormal SST pattern maintains to May and triggers a zonal wave train from the North Atlantic through Scandinavia and Central Asia to Northwest China,leading to abnormal cyclones in Northwest ***,Northwest China experiences a more humid climate than usual.

关键词： Arctic sea ice Greenland Sea North Atlantic SST Drought Northwest China

Cell polarization in ischemic stroke: molecular mechanisms and advances

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Neural Regeneration Research 2025年第3期20卷 632-645页

作者： Yuanwei Li Xiaoxiao Xu Xuan Wu Jiarui Li Shiling chen Danyang chen Gaigai Li Zhouping Tang Department of Neurology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

Ischemic stroke is a cerebrovascular disease associated with high mortality and disability rates. Since the inflammation and immune response play a central role in driving ischemic damage, it becomes essential to modulate excessive inflammatory reactions to promote cell survival and facilitate tissue repair around the injury site. Various cell types are involved in the inflammatory response, including microglia, astrocytes, and neutrophils, each exhibiting distinct phenotypic profiles upon stimulation. They display either proinflammatory or anti-inflammatory states, a phenomenon known as ‘cell polarization.’ There are two cell polarization therapy strategies. The first involves inducing cells into a neuroprotective phenotype in vitro, then reintroducing them autologously. The second approach utilizes small molecular substances to directly affect cells in vivo. In this review, we elucidate the polarization dynamics of the three reactive cell populations(microglia, astrocytes, and neutrophils) in the context of ischemic stroke, and provide a comprehensive summary of the molecular mechanisms involved in their phenotypic switching. By unraveling the complexity of cell polarization, we hope to offer insights for future research on neuroinflammation and novel therapeutic strategies for ischemic stroke.

关键词： astrocyte polarization immune regulation inflammation ischemic injury microglia polarization neutrophil polarization signaling pathways stroke

Chemical and chemoenzymatic stereoselectivesynthesis of β-nucleosides and their analogues

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Organic Chemistry Frontiers 2022年第6期9卷 1719-1741页

作者： Hui-Jing Wang Yang-Yang Zhong You-cai Xiao Fen-er chen Sichuan Research Center for Drug Precision Industrial Technology West China School of PharmacySichuan UniversityChengdu610041China Engineering Center of Catalysis and Synthesis for Chiral Molecules Department of ChemistryFudan UniversityShanghai200433China Shanghai Engineering Center of Industrial Asymmetric Catalysis for Chiral Drugs Shanghai 200433ChinaShanghai200433China

β-Nucleosides are fundamental building blocks of biological systems and are widely used as therapeuticagents for the treatment of cancer and viral infections, among others. In the last two years, nucleosideanalogues have been investigated with renewed urgency in the search for agents that are effective againstSARS-CoV-2, the cause of the ongoing global pandemic of COVID-19. This has resulted in an explosionof activities in the field of β-nucleoside synthesis. This review summarizes the historical perspective andthe recent advances in the stereoselective synthesis of β-nucleosides and their analogues. The syntheticstrategies to obtain β-nucleosides can be divided into three categories: (1) N-glycosylation;(2) intramolecular sugar ring formation;and (3) enzymatic transglycosylation.

关键词： synthesis analogues nucleoside

Engineering atomic Rb-N configurations to tune radical pathways for highly selective photocatalytic H2O2 synthesis coupled with biomass valorization

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Journal of Energy Chemistry 2025年第1期100卷 215-225页

作者： Jiaye Li Shuang Pan Yihuang chen Qiong Liu College of Chemistry and Materials Engineering Wenzhou University Guangdong Provincial Key Laboratory of Chemical Measurement and Emergency Test Technology (China) Institute of Analysis Guangdong Academy of Sciences (China National Analytical CenterGuangzhou)

Photocatalytic oxygen reduction for hydrogen peroxide （H2O2） synthesis presents a green and costeffective production ***,achieving highly selective H2O2synthesis remains challenging,necessitating precise control over free radical reaction pathways and minimizing undesirable oxidative ***,we report for the visible light-driven simultaneous co-photocatalytic reduction of O2to H2O2and oxidation of biomass using the atomic rubidium-nitride modified carbon nitride（CNRb）.The optimized CNRb catalyst demonstrates a record photoreduction rate of 8.01 mM h-1for H2O2generation and photooxidation rate of 3.75 mM h-1for furfuryl alcohol to furoic acid,achieving a remarkable solar-to-chemical conversion （SCC） efficiency of up to 2.27%.Experimental characterizations and DFT calculation disclosed that the introducing atomic Rb–N configurations allows for the high-selective generation of superoxide radicals while suppressing hydroxyl free radical *** is because the Rb–N serves as the new alternative site to perceive a stronger connection position for O2adsorption and reinforce the capability to extract protons,thereby triggering a high selective redox product *** study holds great potential in precisely regulating reactive radical processes at the atomic level,thereby paving the way for efficient synthesis of H2O2coupled with biomass valorization.

关键词： Atomic economy Radical pathway regulation Rubidium atom coordination Biomass valorization