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Evaluation of the forest ecosystem health in Beijing area

Forestry Studies in China 2007年第2期9卷 157-163页

作者： Ma Li han Hai-rong Ma qin-yan Liu Hong-wen Xia Wei-wei Cheng Xiao-qin Key Laboratory for Silviculture and Conservation of Ministry of Education College of Natural Resources and Environment BeijingForestry University Beijing 100083 P. R. China

The evaluation of ecosystem health has become one of the main research topics of ecosystem science, thus more and more assessment methods and frameworks have been put forward in recent years. However, the attention people pay to ecosystem health is actually more about what the social functions the ecosystem affords, which depend on the integrity and maintenance of the ecosystem structure and function, and the intensity of disturbance from outside. Accordingly, this research commenced from three main aspects, selected the evaluation indices, and then established the Evaluation Index System of Beijing Forest Ecosystem Health （EIS-BFEH）. In the EIS-BFEH, each of the three foundations contained an easily-operated and standard sub-index system, which compounded the specific natural and social conditions of Beijing and was concrete enough to measure and evaluate. Then with the method of the Analytical Hierarchy Process （AHP）, the comprehensive index （CI） could be obtained, which represented the health of the forest ecosystem. As a case study, the forest ecosystems in the Badaling area were sampled, evaluated, compared and ranked by use of the EIS-BFEH. The result show that the health of natural forests is much better than that of plantations in the Badaling forest center： the average comprehensive index of the former is 7.9, while the latter is only 6.6. From the results, it could also be found that there are nine units in the healthy state, two units in the subhealthy state, and only one unit of Robiniapseudoacacia in the morbid state.

关键词： Beijing area forest ecosystem health evaluation Badaling Forest Center

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Empirical likelihood for spatial cross-sectional data models with matrix exponential spatial specification

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 125-139页

作者： LIU Yan rong Jian-rong qin Yong-song Nanning University Nanning 530200China Center for Applied Mathematics of Guangxi and College of Mathematics and Statistics Guangxi Normal UniversityGuilin 541004China

In this paper,we study spatial cross-sectional data models in the form of matrix exponential spatial specification(MESS),where MESS appears in both dependent and error *** empirical likelihood(EL)ratio statistics are established for the parameters of the MESS *** is shown that the limiting distributions of EL ratio statistics follow chi-square distributions,which are used to construct the confidence regions of model *** experiments are conducted to compare the performances of confidence regions based on EL method and normal approximation method.

关键词： MESS empirical likelihood con dence region

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Expression of insulin-like growth factor Ⅱ and its receptor in hepatocellular carcinogenesis

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World Journal of Gastroenterology 2001年第2期7卷 285-288页

作者： Zi rong Fan Dong Hua Yang Jun Cui han rong qin Chun Chi Huang Department of Gastroenterology, Zhujiang Hospital. The First Military Medical University, Guangzhou 510282.Guangdong Province. China Department of Gastroenterology Zhujiang Hospital The First Military Medical University Guangzhou 510282 Guangdong Province China.

INTRODUCTIONInsulin-like growth factor Ⅱ(IGF-Ⅱ) is a mitogenic peptide of 74 kD and is mostly synthesized in fetal liver tissue .IGF-Ⅱ is believed to play an important role in fetal growth and development and is involved in cellular proliferation and differentiation[1-5]. Recently ,several researchers have reported increased expression of the IGF-Ⅱgene in human hepatocellular carcinoma (HCC) and adjacent non-cancerous liver tissues [6-10].

关键词： liver neoplasms/pathology insulin-like growth factor Ⅱ/biosynthesis receptors,somatomedin/biosynthesis RNA, messenger/biosynthesis in situ hybridization hepatitis,chronic/pathology

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Learning in games:a systematic review

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Science China(Information Sciences) 2024年第7期67卷 133-159页

作者： rong-Jun qin Yang YU National Key Laboratory for Novel Software Technology Nanjing University Polixir Technologies

Game theory studies the mathematical models for self-interested individuals. Nash equilibrium is arguably the most central solution in game theory. While finding the Nash equilibrium in general is known as polynomial parity arguments on directed graphs(PPAD)-complete, learning in games provides an alternative to approximate Nash equilibrium, which iteratively updates the player's strategy through interactions with other players. Rules and models have been developed for learning in games, such as fictitious play and no-regret learning. Particularly, with recent advances in online learning and deep reinforcement learning,techniques from these fields greatly boost the breakthroughs in learning in games from theory to *** a result, we have witnessed many superhuman game AI systems. The techniques used in these systems evolve from conventional search and learning to purely reinforcement learning(RL)-style learning methods,gradually getting rid of the domain knowledge. In this article, we systematically review the above techniques,discuss the trend of basic learning rules towards a unified framework, and recap applications in large ***, we discuss some future directions and make the prospect of future game AI systems. We hope this article will give some insights into designing novel approaches.

关键词： non-cooperative games learning in games no-regret learning reinforcement learning superhuman AI

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Bilayer Compounded Polytetrafluoroethylene Membrane for Enhanced Oil-Water Emulsion Separation

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Chinese Journal of Polymer Science 2024年第6期42卷 838-850页

作者： Yu-Liang Yang Tai-Ran Zhang Yan-Ting han Shao-Yun Guo qin-Gong rong Jia-Bin Shen State Key Laboratory of Polymer Materials Engineering Polymer Research Institute of Sichuan UniversitySichuan Provincial Engineering Laboratory of Plastic/Rubber Complex Processing TechnologyChengdu610065China West China Hospital/West China School of Nursing Sichuan UniversityChengdu610041China Shandong Senrong New Materials Co. Ltd.Zibo256401China

In order to achieve efficient and durable oil-water emulsion separation,the membranes possessing high separation efficiency and mechanical strength attract extensive attention and are in great *** present study,a kind of polytetrafluoroethylene(PTFE)-based bilayer membrane was fabricated by electrospinning fibrous PTFE(fPTFE)on an expanded PTFE(ePTFE)*** morphological observation revealed that the fibrous structure of the fPTFE layer could be tailored by controlling the formulation of spinning *** addition of appropriate polyoxyethylene(PEO)would make the fibers in the fPTFE layer finer and more *** a result,the compounded membrane exhibited a small pore size of approximately 1.25µm and a substantial porosity nearing 80%.This led to super-hydrophobicity,characterized by a high water contact angle(WCA)of 149.8°,and facilitated rapid oil *** water-in-oil emulsion separation experiment further confirmed that the compounded membrane not only had a high separation efficiency closing 100%,but such an outstanding separation capacity could be largely retained,either through multiple cycles of use or through strong acid(pH=1),strong alkali(pH=12),or high-temperature(100°C)***,the mechanical behavior of the bilayer membrane was basically contributed by that of each layer in terms of their volume *** significantly,the poor creep resistance of fPTFE layer was suppressed by compounding with ePTFE ***,this study has laid the groundwork for a novel approach to create PTFE-based compounded membranes with exceptional overall characteristics,showing promise for applications in the realm of emulsion separation.

关键词： ePTFE Electrospinning membrane Bilayer compounding Emulsion separation

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Making waste profitable: Efficient recovery of metallic iron from jarosite residues

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Chinese Journal of Chemical Engineering 2024年第7期71卷 66-76页

作者： Songshan Zhou Yunhui han rong Huang Yin Huang qingyuan Dong Haiyin Gang Jinchuan qin Xi Yu Xiangfei Zeng Wenxing Cao Jiqin Wang Shaoqin Chen rong Wang Mengjun Chen Key Laboratory of Solid Waste Treatment and Resource Recycle(SWUST) Ministry of EducationSouthwest University of Science and TechnologyMianyang 621010China School of Environment Key Laboratory of Yellow River and Huai River Water Environment and Pollution ControlMinistry of EducationHenan Normal UniversityXinxiang 453007China School of National Defense Science and Technology College SWUST Ministry of EducationSouthwest University of Science and TechnologyMianyang 621010China

To address the hazardous by-product of zinc smelting and resource utilization of jarosite residue,this study applies an electric field-assisted hot acid treatment to completely recycle iron(Fe).This innovative approach aims to enhance the leaching efficiency of Fe from jarosite *** introduction of an electric field changes the charge distribution on the surface of the particles to enhance ions and electrons exchange and promotes the collision between particles to strengthen reaction *** on the above,the leaching efficiency of Fe in jarosite under sulfuric acid attack has improved *** result shows that Fe leaching efficiency reaches 98.83%,which is increased by 28%under the optimal experimental conditions:current density of 30 mA·cm^(-2),H_(2)SO_(4) concentration of 1.5 mol·L^(-1),solid-liquid ratio of 70 g·L^(-1),temperature of 80℃ and time of 12 *** kinetics calculations show that the apparent activation energy is 16.97 kJ·mol^(-1) and the leaching of jarosite residue is controlled by a mixture of chemical reaction and diffusion,as well as the temperature and concentration of the leaching solution have an influence on *** work provides a feasible idea for the efficient leaching of Fe from jarosite residue.

关键词： Jarosite residue Electric filed Leaching kinetics

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A Tri-mode of Mock-Walker Cells

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Advances in Atmospheric Sciences 2024年第4期41卷 671-679页

作者： han qin Ji NIE Zhiyong MENG Laboratory for Climate and Ocean-Atmosphere Studies Department of Atmospheric and Oceanic SciencesSchool of PhysicsPeking UniversityBeijing 100871China China Meteorological Administration Tornado Key Laboratory Foshan 528061China

This work uses cloud-resolving simulations to study mock-Walker cells driven by a specified sea surface temperature(SST).The associated precipitation in the mock-Walker cells exhibits three different modes,including a single peak of precipitation over the SST maximum(mode 1),symmetric double peaks of precipitation straddling the SST maximum(mode 2),and a single peak of precipitation on one side of the SST maximum(mode 3).The three modes are caused by three distinct convective activity center migration *** indicate that the virtual effect of water vapor plays an important role in differentiating the three *** the SST gradient is large,the virtual effect may be strong enough to overcome the temperature effect,generating a low-level low-pressure anomaly below the ascending branch of the Walker cell off the *** results here highlight the importance of the virtual effect of water vapor and its interaction with convection and large-scale circulation in the Walker circulation.

关键词： Walker circulation cloud-resolving simulation virtual effect

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Evaluation of the Effectiveness of“5E”Comprehensive Injury Prevention Strategy for Fall Prevention Among the Rural Elderly—Six Pilot Villages,Yunnan Province and Chongqing Municipality,China,2018–2023

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China CDC weekly 2024年第14期6卷 277-281页

作者： Fujin Sun rong Luo Hui han National Center for Women and Children’s Health Chinese Center for Disease Control and PreventionBeijingChina

What is already known about this topic?The mortality rate and disease burden associated with falls among the elderly in China are on the *** can play a crucial role in preventing and managing *** is added by this report?The application of the“5E”injury prevention strategy led to a decrease in both the occurrence of falls and the likelihood of subsequent *** physical activity and maintaining a positive outlook were identified as protective measures against falls,while sleep issues and hearing impairment were found to increase the risk of *** are the implications for public health practice?The group-based comprehensive intervention strategy is crucial as it offers an innovative intervention model and empirical evidence for decreasing fall rates among elderly individuals living in rural areas.

关键词： Chongqing Rural prevention

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Evaluation and Projection of Population Exposure to Temperature Extremes over the Beijing−Tianjin−Hebei Region Using a High-Resolution Regional Climate Model RegCM4 Ensemble

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Advances in Atmospheric Sciences 2024年第6期41卷 1132-1146页

作者： Peihua qin Zhenghui XIE Rui han Buchun LIU State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural Sciences(CAAS)Beijing 100081China

Temperature extremes over rapidly urbanizing regions with high population densities have been scrutinized due to their severe impacts on human safety and *** of all,the performance of the regional climate model RegCM4 with a hydrostatic or non-hydrostatic dynamic core in simulating seasonal temperature and temperature extremes was evaluated over the historical period of 1991–99 at a 12-km spatial resolution over China and a 3-km resolution over the Beijing−Tianjin−Hebei(JJJ)region,a typical urban agglomeration of *** of spatial distributions of temperature extremes over the JJJ region using RegCM4 with hydrostatic and non-hydrostatic cores showed high spatial correlations of more than 0.8 with the *** a warming climate,temperature extremes of annual maximum daily temperature(TXx)and summer days(SU)in China and the JJJ region showed obvious increases by the end of the 21st century while there was a general reduction in frost days(FD).The ensemble of RegCM4 with different land surface components was used to examine population exposure to temperature extremes over the JJJ *** exposure to temperature extremes was found to decrease in 2091−99 relative to 1991−99 over the majority of the JJJ region due to the joint impacts of increases in temperature extremes over the JJJ and population decreases over the JJJ region,except for downtown ***,changes in population exposure to temperature extremes were mainly dominated by future population ***,we quantified changes in exposure to temperature extremes with temperature increase over the JJJ *** study helps to provide relevant policies to respond future climate risks over the JJJ region.

关键词： CMIP6 convection-permitting population exposure RegCM4 temperature extremes

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A Mass-Preserving Characteristic Finite Difference Method For Miscible Displacement Problem

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Advances in Applied Mathematics and Mechanics 2024年第1期16卷 164-180页

作者： Jiansong Zhang Yue Yu rong qin Zhaohui Liu Department of Applied Mathematics China University of PetroleumQingdaoShandong 266580China

In this article,a new characteristic finite difference method is developed for solving miscible displacement problem in porous *** new method combines the characteristic technique with mass-preserving interpolation,not only keeps mass balance but also is of second-order accuracy both in time and *** results are presented to confirm the convergence and the accuracy in time and space.

关键词： The method of characteristics mass-preserving finite difference miscible displacement problem

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