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Kinetic theory of Jeans'gravitational instability in millicharged dark matter system

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Chinese Physics B 2022年第7期31卷 152-156页

作者： Hui chen Wei-Heng Yang Yu-zhen Xiong San-qiu Liu Jiangxi Province Key Laboratory of Fusion and Information Control Department of PhysicsNanchang UniversityNanchang 330031China

The possibility of baryons cooled by a millicharged dark matter(mDM)via mDM–baryons scattering has recently been proposed to explain the observation discrepancy from the experiment to detect the global epoch of reionization signature(EDGES).In this sense,we analyze the Jeans instability of self-gravitational systems in the background of mDM under kinetic regime that the collisionless Boltzmann equation and Poisson equation have been combined to obtain the modified dispersion *** is shown that the effect of mDM is significant on the dynamics of gravitational collapse,i.e.,the presence of mDM makes the self-gravitational systems more difficult to collapse relatively.

关键词： self-gravitating systems millicharged dark matter Jeans instability

血清Dickkopf-1蛋白在早期诊断股骨头坏死及病情监测中的意义

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中国现代医学杂志 2018年第35期28卷 43-47页

作者：李伟峰陈立新陈哓俊龚水帝庞凤祥何晓铭沈莹姗杨帆杨鹏何伟魏秋实陈镇秋广州中医药大学第一临床医学院广东广州510405 广州中医药大学第一附属医院三骨科广东广州510405 广州中医药大学第一附属医院三骨科保髋区广东广州510405

目的通过检测股骨头坏死患者血清Dickkopf-1(DKK-1)蛋白含量变化,探究其在早期诊断股骨头坏死及病情监测中的意义。方法选取2016年5月—2016年11月于广州中医药大学第一附属医院住院的股骨头坏死患者67例(ARCO分期:Ⅱ期13例、Ⅲ期27例... 详细信息

目的通过检测股骨头坏死患者血清Dickkopf-1(DKK-1)蛋白含量变化,探究其在早期诊断股骨头坏死及病情监测中的意义。方法选取2016年5月—2016年11月于广州中医药大学第一附属医院住院的股骨头坏死患者67例(ARCO分期:Ⅱ期13例、Ⅲ期27例、Ⅳ期27例)作为实验组,并随机选取67例同期在该院体检中心体检正常者作为对照组,采用ELISA法检测两组患者的血清DKK-1蛋白浓度,比较并分析实验组与对照组、实验组内不同病因、不同ARCO分期患者的血清DKK-1蛋白浓度差异。结果实验组血清DKK-1蛋白浓度高于对照组(P 0.05);实验组ARCOⅡ、Ⅲ及Ⅳ期的患者血清DKK-1蛋白浓度比较,差异有统计学意义(P<0.05)。ROC曲线分析提示血清DKK-1蛋白在诊断股骨头坏死塌陷时具有一定的敏感性和显著的特异性,分别为57.40%和100.00%。血清DKK-1蛋白浓度与ARCO分期呈正相关(P<0.05)。结论血清DKK-1蛋白浓度与股骨头坏死患者的病情进展密切相关,对早期诊断股骨头坏死及监测患者病情变化具有一定的参考意义,可作为临床诊断及治疗的参考指标之一。

关键词：股骨头坏死 Dickkopf-1/蛋白酶联免疫吸附测定早期诊断

Integrating NLP and Ontology Matching into a Unified System for Automated Information Extraction from Geological Hazard Reports

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Journal of Earth Science 2023年第5期34卷 1433-1446页

作者： Qinjun qiu zhen Huang Dexin Xu Kai Ma Liufeng Tao Run Wang Jianguo chen Zhong Xie Yongsheng Pan Key Laboratory of Urban Land Resources Monitoring and Simulation Ministry of Natural ResourcesShenzhen 518034China Key Laboratory of Geological Survey and Evaluation of Ministry of Education China University of GeosciencesWuhan 430074China Beijing Key Laboratory of Urban Spatial Information Engineering Beijing 100045China School of Geography and Information Engineering China University of GeosciencesWuhan 430074China Wuhan Geomatics Institute Wuhan 430074China College of Computer and Information Technology China Three Gorges UniversityYichang 443002China Hubei Key Laboratory of Intelligent Vision Based Monitoring for Hydroelectric Engineering China Three Gorges UniversityYichang 443002China Geological Environmental Center of Hubei Province Wuhan 430034China Faculty of Earth Resources China University of GeosciencesWuhan 430074China State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430078China Wuhan Zondy Cyber Science&Technology Co. Ltd.Wuhan 430074China

Many detailed data on past geological hazard events are buried in geological hazard reports and have not been fully utilized. The growing developments in geographic information retrieval and temporal information retrieval offer opportunities to analyse this wealth of data to mine the spatiotemporal evolution of geological disaster occurrence and enhance risk decision making. This study presents a combined NLP and ontology matching information extraction framework for automatically recognizing semantic and spatiotemporal information from geological hazard reports. This framework mainly extracts unstructured information from geological disaster reports through named entity recognition, ontology matching and gazetteer matching to identify and annotate elements, thus enabling users to quickly obtain key information and understand the general content of disaster reports. In addition, we present the final results obtained from the experiments through a reasonable visualization and analyse the visual results. The extraction and retrieval of semantic information related to the dynamics of geohazard events are performed from both natural and human perspectives to provide information on the progress of events.

关键词： geological hazard report spatiotemporal information geological hazard ontology natural language processing gazetteers onlology machine learning

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Building a PEG-C@MoSe_(2)@CNT heterostructure via in-situ selenidation as highly reversible anodes for Na+batteries

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Science China Chemistry 2023年第2期66卷 475-491页

作者： Yincai Yang Feng Wang Youwen chen Changmiao chen Shiguo Zhang zhen-Qiang Yu Chak-Tong Au Shuang-Feng Yin Renhua qiu State Key Laboratory of Chemo/Biosensing and Chemometrics Advanced Catalytic Engineering Research Centre of the Ministry of EducationCollege of Chemistry and Chemical EngineeringSchool of Physics&ElectronicsCollege of Material Science and Chemical EngineeringHunan UniversityChangsha410082China College of Information and Mechatronic Engineering Hunan International Economics UniversityChangsha410082China College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen518000China

Herein,we describe a simple and efficient method to build C@MoSe_(2)@CNT composites that exhibit good electrochemical performance as anode materials for sodium-ion *** protocol uses commercially available and cheap carbon nanotubes(CNT)as the conductive *** selenide(MoSe_(2)),in-situ-synthesized from Mo-ethylene glycol(poly(ethylene glycol)(PEG,M_(n)≈200))complexes,grows along the CNT with a discontinuous morphology,which creates multiple channels for the insertion of Na^(+).Meanwhile,PEG-C provides a thin carbon coating layer to increase *** PEG-200-2-C/MoSe_(2)/CNTat room temperature,the storage at 2 A g^(-1)is 426 m A h g^(-1)after 500 cycles and 212 m A h g^(-1)after 3,000 *** with pure MoSe_(2),density functional theory calculations indicate that the Na^(+)diffusion barrier in the MoSe_(2)of C@MoSe_(2)@CNT effectively decreases from 0.91 to 0.72 e V,hence promoting the reversibility of the Na^(+)storage.

关键词： sodium-ion batteries MoSe_(2) CNT

Boosting cationic and anionic redox activity of Li-rich layered oxide cathodes via Li/Ni disordered regulation

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Journal of Energy Chemistry 2025年第1期 533-543页

作者： Zewen Liu zhen Wu Hao Wang Xudong Zhang Yuanzhen chen Yongning Liu Shengwu Guo Shenghua chen Yanli Nan Yan Liu State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University School of Materials Science and Engineering Xi'an University of Architecture and Technology Hefei Advanced Computing Center Operation Management Corp Ltd Network Information Center Xi'an Jiaotong University

Lithium-rich layered oxides （LLOs） are increasingly recognized as promising cathode materials for nextgeneration high-energy-density lithium-ion batteries （LIBs）.However,they suffer from voltage decay and low initial Coulombic efficiency （ICE） due to severe structural degradation caused by irreversible O ***,we introduce a three-in-one strategy of increasing Ni and Mn content,along with Li/Ni disordering and TM–O covalency regulation to boost cationic and anionic redox activity simultaneously and thus enhance the electrochemical activity of *** target material,Li1.2Ni0.168Mn0.558Co0.074O2（L1）,exhibits an improved ICE of 87.2%and specific capacity of 293.2 mA h g-1and minimal voltage decay of less than 0.53 m V cycle-1over 300 cycles at 1C,compared to Li1.2Ni0.13Mn0.54Co0.13O2（Ls）(274.4 mA h g-1for initial capacity,73.8%for ICE and voltage decay of 0.84 mV/cycle over 300 cycles at 1C).Theoretical calculations reveal that the density of states （DOS） area near the Fermi energy level for L1 is larger than that of Ls,indicating higher anionic and cationic redox reactivity than ***,L1 exhibits increased O-vacancy formation energy due to higher Li/Ni disordering of 4.76%（quantified by X-ray diffraction Rietveld refinement） and enhanced TM–O covalency,making lattice O release more difficult and thus improving electrochemical *** increased Li/Ni disordering also leads to more Ni2+presence in the Li layer,which acts as a pillar during Li+de-embedding,improving structural *** research not only presents a viable approach to designing low-Co LLOs with enhanced capacity and ICE but also contributes significantly to the fundamental understanding of structural regulation in high-performance LIB cathodes.

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Deep Learning and Network Analysis:Classifying and Visualizing Geologic Hazard Reports

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Journal of Earth Science 2024年第4期35卷 1289-1303页

作者： Wenjia Li Liang Wu Xinde Xu Zhong Xie Qinjun qiu Hao Liu zhen Huang Jianguo chen School of Geography and Information Engineering China University of GeosciencesWuhan430078China Key Laboratory of Geological Survey and Evaluation of Ministry of Education China University of GeosciencesWuhan430078China School of Computer Science China University of GeosciencesWuhan430078China Key Laboratory of Urban Land Resources Monitoring and Simulation Ministry of Natural ResourcesShenzhen518034China Hubei Key Laboratory of Intelligent Vision Based Monitoring for Hydroelectric Engineering China Three Gorges UniversityYichang443002China Wuhan Geomatics Institute Wuhan430074China Faculty of Earth Resources China University of GeosciencesWuhan430074China

If progress is to be made toward improving geohazard management and emergency decision-making,then lessons need to be learned from past geohazard information.A geologic hazard report provides a useful and reliable source of information about the occurrence of an event,along with detailed information about the condition or factors of the *** such reports,however,can be a challenging process because these texts are often presented in unstructured long text formats,and contain rich specialized and detailed *** text classification is commonly used to mine disaster text data in open domains(e.g.,news and microblogs).But it has limitations to performing contextual long-distance dependencies and is insensitive to discourse *** deficiencies are most obviously exposed in long text ***,this paper uses the bidirectional encoder representations from Transformers(BERT),to model long ***,utilizing a softmax layer to automatically extract text features and classify geohazards without manual *** latent Dirichlet allocation(LDA)model is used to examine the interdependencies that exist between causal variables to visualize *** proposed method is useful in enabling the machine-assisted interpretation of text-based ***,it can help users visualize causes,processes,and other geohazards and assist decision-makers in emergency responses.

关键词： geologic hazard network analysis latent dirichlet allocation text classification deep learning

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基于基因组重测序的沉香遗传多样性研究

热带作物学报 2025年第1期46卷 51-58页

作者：苟志辉陈国德甄云楠王鑫陈彧田蜜海南省林业科学研究院(海南省红树林研究院) 海南海口571100 海南省热带林业资源监测与应用重点实验室海南海口571100 海口市湿地保护管理中心海南海口571100

对种质资源信息的掌握是土沉香遗传改良的基础,而基因组重测序是种质资源遗传多样性分析的利器,然而目前学术界缺乏利用基因组重测序对土沉香遗传多样性的研究。本研究在前期收集得到的沉香种质资源基础上,采用基因组重测序,获得60份沉... 详细信息

对种质资源信息的掌握是土沉香遗传改良的基础,而基因组重测序是种质资源遗传多样性分析的利器,然而目前学术界缺乏利用基因组重测序对土沉香遗传多样性的研究。本研究在前期收集得到的沉香种质资源基础上,采用基因组重测序,获得60份沉香共1284 Gb重测序数据。利用沉香基因组,共检测得到6 713 166个高质量变异位点,其中SNP位点6 284 344个,Indel位点428 658个。主成分分析、系统发育分析和遗传结构分析均表明,沉香可分为3个显著群体(Pop1、Pop2和Pop3),其中2个群体可分别进一步划分为多个亚群。在3个群体中均检测到群体选择信号,其中Pop3选择信号最多,而核苷酸多态性计算结果表明,Pop3的核苷酸多态性最低。本研究为探究沉香遗传资源多样性提供了有价值的信息,并为基于基因组的沉香遗传育种奠定理论基础。

关键词：沉香基因组重测序变异位点遗传多样性

Hitting Probabilities and Fractal Dimensions of Multiparameter Multifractional Brownian Motion

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Acta Mathematica Sinica,English Series 2013年第9期29卷 1723-1742页

作者： zhen Long chen School of Statistics and Mathematics Zhejiang Gongshang University

The main goal of this paper is to study the sample path properties for the harmonisable-type N-parameter multifractional Brownian motion, whose local regularities change as time evolves. We provide the upper and lower bounds on the hitting probabilities of an （N, d）-multifractional Brownian motion. Moreover, we determine the Hausdorff dimension of its inverse images, and the Hausdorff and packing dimensions of its level sets.

关键词： Multifractional Brownian motion hitting probability inverse image level set Hausdorff dimension packing dimension

Polar Functions of Multiparameter Bifractional Brownian Sheets

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Acta Mathematicae Applicatae Sinica 2009年第2期25卷 255-272页

作者： zhen-long chen College of Statistics and Mathematics Zhejiang Gongshang University Hangzhou 310018 China

Let B^H,K ：（B^H,K（t）, t ∈R＋^N} be an （N,d）-bifractional Brownian sheet with Hurst indices H = （H1,..., HN） ∈ （0, 1）^N and K = （K1,..., KN）∈ （0, 1]^N. The characteristics of the polar functions for B^H,K are investigated. The relationship between the class of continuous functions satisfying the Lipschitz condition and the class of polar-functions of B^H,K is presented. The Hausdorff dimension of the fixed points and an inequality concerning the Kolmogorov＇s entropy index for B^H,K are obtained. A question proposed by LeGall about the existence of no-polar, continuous functions statisfying the Holder condition is also solved.

关键词： Bifractional Brownian sheet polar function Hausdorff dimension packing dimension capacity