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Spatial heterogeneity of the driving forces of cropland change in China

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Science China Earth Sciences 2005年第12期48卷 2231-2240页

作者： LIU Xuhua1,2, WANG Jinfeng1, LIU Mingliang4,1 & MENG Bin1,2,3 1. institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China 2. Graduate School of the Chinese Academy of Sciences, Beijing 100039, China 3. College of Arts and Sciences of Beijing Union University, Beijing 100083, China 4. School of Forestry and Wildlife Sciences, Auburn University, Auburn, Alabama, AL36849, USA institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Graduate School of the Chinese Academy of Sciences Beijing China School of Forestry and Wildlife Sciences Auburn University Auburn Alabama USA College of Arts and Sciences of Beijing Union University Beijing China

By using digital satellite remote sensing data acquired in 1987―1989 and 1999―2000 and GIS combined with the natural and socio-economic data, this paper drew an integrated zonation of the cropland change and its driving forces in China. The results indicated that the cropland change in the study period was constrained by geographical factors and driven by cli-mate change as well as socio-economic system. Moreover, the regional differences of the drivers for cropland change were significant. In the midwest of China, natural condition changes and geographical background were the main constraints and drivers, while in Eastern China, social and economic changes and economic policies were the main driving forces. The cropland loss was nationwide. The dominant factors to cause this decrease included buildup of developing area to attract foreign capital and technologies, changes of industry structure due to urban in-fluence, the change of employment notions thanks to living standard improvement, rapid ur-banization due to the expansion of cities and towns, the diminished farming net income partly because of the global warming effects, and the rapid economic growth stimulated by the con-venient transportation system. These factors interact and interdepend with each other to cause the cropland loss in China recently. The reasons for the increase of cropland were primarily the cultivation and deforestation by the farmers who want to increase income. This study on the mechnism of LUCC relied on the cropland change integrated classification considering the natural or human factors both inside and outside the region, which provides a new approach to study the integrated regionalization and LUCC mechanism.

关键词： land use change, driving force, integrated classification, spatial statistics, cropland, China.

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中美过去300年土地利用变化比较

地理学报 2015年第2期70卷 297-307页

作者：何凡能李美娇李士成肖冉 Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research CAS University of Chinese Academy of Sciences

开展历史土地利用变化的国别对比研究,不仅有利于深化大尺度LUCC过程与驱动机制的科学认识,而且对深入研究历史碳排放责任等也有着重要意义。利用长时间序列数据,对中美两国过去300年土地利用/覆被变化的时空特征及驱动因素进行对比分... 详细信息

开展历史土地利用变化的国别对比研究,不仅有利于深化大尺度LUCC过程与驱动机制的科学认识,而且对深入研究历史碳排放责任等也有着重要意义。利用长时间序列数据,对中美两国过去300年土地利用/覆被变化的时空特征及驱动因素进行对比分析。结果表明:1过去300年中美两国耕地数量总体均呈持续增长态势,中国在1661-1980s的320余年间耕地总量增长了79.46×104km2,但人均耕地面积却从1685年的5.5亩,下降至2000年的1.5亩;而美国在1700-1950年的250年间耕地面积增加了190.87×104km2,且人均耕地面积均超过9亩,其中1890年高达30.2亩。2受土地垦殖扩张影响,过去300年中美两国林、草地资源均呈持续减少态势;其中,美国森林面积减少了约145×104km2,草地面积减少约137×104km2;而中国森林面积减少了约90×104km2,草地面积减少了约40×104km2。3从空间格局变化特征看,过去300年中国土地垦殖主要向边区(如东北、西南、内蒙等)及内地山地丘陵区发展;而美国在"西进运动"的影响下,大规模向中西部拓殖。4政策、人口、农业技术等因素是影响过去300年中美土地利用/覆被变化的主要因素,但由于两国资源禀赋及发展历史的差异,虽然直接驱动力均体现为政策因素,但就根本驱动因素而言,中国是人口数量,美国则是经济利益;同时,在农业技术发展取向上,中国因"人多地少",走"精耕细作"之路,而美国因"人少地多",走"机械化"之途。

关键词：土地利用/覆被变化历史比较过去300年中国美国

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Season of the year influences infection rates following total hip arthroplasty

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World Journal of Orthopedics 2017年第12期8卷 895-901页

作者： Samuel Rosas Alvin C Ong Leonard T Buller Karim G Sabeh Tsun yee Law Martin W Roche Victor H Hernandez Department of Orthopedic Surgery Wake Forest School of Medicine Holy Cross Orthopedic institute Orthopedic Surgery Thomas Jefferson University Hospital Department of Orthopedics Surgery University of Miami Department of Orthopaedic Surgery Holy Cross Hospital

AIM To research the influence of season of the year on periprosthetic joint *** We conducted a retrospective review of the entire Medicare files from 2005 to 2014. Seasons were classified as spring, summer, fall or winter. Regional variations were accounted for by dividing patients into four geographic regions as per the United States Census Bureau(Northeast, midwest, West and South). Acute postoperative infection and deep periprosthetic infections within 90 d after surgery were tracked. RESULTS In all regions, winter had the highest incidence of periprosthetic infections(mean 0.98%, SD 0.1%) and was significantly higher than other seasons in the midwest, South and West(P < 0.05 for all) but not the Northeast(P = 0.358). Acute postoperative infection rates were more frequent in the summer and were significantly affected by season of the year in the *** Season of the year is a risk factor for periprosthetic joint infection following total hip arthroplasty(THA). Understanding the influence of season on outcomes following THA is essential when risk-stratifying patients to optimize outcomes and reduce episode of care costs.

关键词： Hip arthroplasty Healthcare Infection Outcomes Season

Household Use of Composted Manure and Phosphorous-Free Fertilizers: Feeling Good versus Doing Good

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Journal of Environmental Protection 2018年第2期9卷 140-157页

作者： Laura McCann Dong Won Shin Department of Agricultural and Applied Economics University of Missouri Columbia MO USA Korea Environment institute Sejong South Korea

Increasing urbanization has led to increasing impermeable surfaces and use of lawn care products. Phosphorous (P) is a major pollutant in freshwater systems, leading to eutrophication, harmful algal blooms and hypoxia. An important source is runoff from urban areas so reducing use of P fertilizers by homeowners would be helpful. This study examines the use of two alternative fertilizer sources in an urbanizing watershed in the midwest, organic fertilizer/composted manure and P-free fertilizer. A mail survey of households was conducted, resulting in a 44% effective response rate. The adoption rates were relatively high (31% and 23% respectively) compared to those found in previous work for rain gardens and rain barrels. Probit regression results found that adoption of both practices was higher among those who tested their soil, knew the watershed concept, and spent more than 10 hours per month gardening. Results for use of composted manure imply that adopters do not view this as fertilizer, which may result in buildup of P levels in the soil over time. Respondents who indicated that water quality was more important than economic development were more likely to use P-free fertilizers. Significant demographic factors for organic fertilizer were somewhat surprising;those with two years of college were more likely to adopt than those with a four-year degree and those with household income of $50,000 - 75,000 were more likely to adopt than those with an income of $75,000 - 100,000. No demographic factors were important for P-free fertilizers.

关键词： Adoption Lawn Care Organic Fertilizer Phosphorous Water Quality

Differential Etiology of Posttraumatic Stress Disorder with Conduct Disorder and Major Depression in Men

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Impact of regional differences in stroke symptom awareness and low-income status on seeking emergency medical service in China

北京论坛（2006）文明的和谐与共同繁荣—对人类文明方式的思考

作者： Karestan C.Koenen Mark W.Miller Andrew C.Heath Kathleen K.Bucholz Michael J.Lyons Seth A.Eisen William R.True Jack Goldberg Ming T.Tsuang Department of Society Human Developmentand HealthHarvard School of Public HealthBostonMA Department of Psychiatry Boston University School of Medicine midwest Alcoholism Research Center at Washington University Department of Psychiatry Washington University School of MedicineSt.LouisMO Department of Psychology Boston UniversityBostonMA Harvard institute of Psychiatric Epidemiology and Genetics Department of EpidemiologyHarvard School of Public HealthBostonMA Department of Psychiatry Harvard Medical School at MassachusettsMental Health CenterBostonMA Department of Internal Medicine Washington University School of MedicineSt.LouisMO Department of Community Health St.Louis University School of Public HealthSt.LouisMO Seattle VA ERIC/Vietnam Era Twin Registry SeattleWashington Department of Epidemiology University of WashingtonSeattleWashington University of California Medical School in San Diego San DiegoCA

Posttraumatic stress disorder(PTSD) is a notable public health *** is an extremely debilitating condition that can occur following exposure to a psychologically distressing event that is outside the range of usual human *** events that can trigger PTSD include violent personal assaults(*** and sexual abuse),natural or human-caused disasters(*** and terrorism bombing),accidents(*** traffic accidents and families of victims),or military *** etiology of PTSD is not clear, although exposure to a traumatic event constitutes a necessary,but not sufficient,*** is highly comorbid with major depression(MD) and conduct disorder(CD) in both epidemiologic and clinical *** of individuals who are at elevated risk for developing PTSD has important implications for public health disaster preparedness and prevention of *** examine the genetic and environmental architecture of the comorbidity of PTSD with MD and CD,we analyzed 6,744 middle aged male-male monozygotic and dizygotic twins from the Vietnam Era Twin Registry maintained in the *** members of a pair were interviewed by telephone using the Diagnostic Interview Schedule for Diagnostic and Statistical Manual of Mental Disorders,Third Edition,Revised(DSM-Ⅲ-R) in *** equation modeling was used to estimate additive genetic,shared environmental and nonshared environmental effects common and specific to PTSD,CD,and MD.A set of competing nested models were assessed by comparing the goodness-of-fit between the full model and the submodel using the chi-square test and *** found that genetic,shared environmental and nonshared environmental influences contributed to 19%(95%CI:11-26%),9%(95%CI:6-17%), and 70%(95%CI:64-77%) of the total variance in PTSD,*** genetic effects on PTSD overlapped with those on MD,while all shared environmental effects on PTSD overlapped with those on *** 3%and 8%of nonshared env

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Chinese Medical Journal 2021年第15期134卷 1812-1818页

作者： Jing Yuan Guang-Liang Shan Sheng-De Li Chun-Peng Gao Li-Ying Cui Bin Peng Department of Neurology Peking Union Medical College HospitalPeking Union Medical CollegeChinese Academy of Medical SciencesBeijing 100730China Department of Epidemiology and Statistics Institute of Basic Medical SciencesChinese Academy of Medical SciencesSchool of Basic MedicinePeking Union Medical CollegeBeijingChina Disease Control and Prevention Office Dalian Municipal Central HospitalDalianLiaoning 116021China

Background:Unawareness of stroke symptoms and low income are two barriers that affect the seeking of emergency medical service(EMS).This study aimed to assess the effect of unawareness and low income on seeking EMS and to investigate the regional distribution of the unawareness and low-income status and their associations with failing to call EMS in ***:A total of 187,723 samples from the China National Stroke Screening Survey was interviewed *** status of awareness and annual income were identified:unaware and low-income,unaware-only,low-income-only,and aware and regular *** outcomes were whether they intended to call EMS or *** regional distribution of each status and their associations with not calling EMS were ***:The status of unaware and low-income,unaware-only,and low-income-only accounted for 6.3%(11,806/187,673),11.9%(22,241/187,673),and 21.5%(40,289/187,673)of the total sample,*** calling EMS was significantly associated with the status of unaware and low-income(odds ratio[OR]:3.21,95%confidence interval[Cl]:3.07-3.35),unaware-only(OR:2.38,95%Cl:2.31-2.46),and low-income-only(OR:1.67,95%Cl:1.63-1.71),compared with the aware and regular income *** midwest regions had higher percentages of people in the unaware and low-income status;the East,South,and Central had higher percentages of unaware-only status;the North and Northeast regions had a higher percentage of low-income-only status,compared with other ***:The existence of the regional difference in unawareness and low income justifies the specific stroke education strategies for the targeted regions and population.

关键词： Stroke Cerebrovascular disease Awareness Income Emergency medical service Developing countries

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Flexible memristors as electronic synapses for neuro- inspired computation based on scotch tape-exfoliated mica substrates

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Nano Research 2018年第3期11卷 1183-1192页

作者： Xiaobing Yan Zhenyu Zhou Jianhui Zhao Qi Liu Hong Wang Guoliang Yuan Jingsheng Chen College of Electron and Information Engineering Key Laboratory of Digital Medical Engineering of Hebei Province Key Laboratory of Optoelectronic Information Materials of Hebei Province Hebei University Baoding 071002 China Key Laboratory of Microelectronic Devices & Integrated Technology Institute of Microelectronics Chinese Academy of Sciences Beijing 100029 China School of Materials Science and Engineering Nanjing University of Science and Technology Nanjing 210094 China Department of Materials Science and Engineering National University of Singapore Singapore 117576 Singapore

Flexible memristor devices based on plastic substrates have attracted considerable attention due to their applications in wearable computers and integrated circuits. However, most plastic-substrate memristors cannot function or be grown in high-temperature environments. In this study, scotch-tape-exfoliated mica was used as the flexible memristor substrate in order to resolve these high-temperature issues. Our TiN/ZHO/IGZO memristor, which was constructed using a thin （10 μm） mica substrate, has superior flexibility and thermostability. After bending it 103 times, the device continues to exhibit exceptional electrical characteristics. It can also be implemented for transitions between high and low resistance states, even in temperatures of up to 300 ℃. More importantly, the biological synaptic characteristics of paired-pulse facilitation/depression （PPF/PPD） and spike- timing-dependent plasticity （STDP） were observed through applying different pulse measurement modes. This work demonstrates that flexible memristor devices on mica substrates may potentially allow for the realization of high-temperature memristor applications for biologically-inspired computing systems.

关键词： mica flexible memristor synapse

Industrial Economy Analysis of Main Pear-producing Counties in Central and Western Shandong Province(2011-2020)

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Agricultural Biotechnology 2022年第3期11卷 123-126页

作者： Shuwei WEI Xiaoyang WANG Shandong institute of Pomology Tai an 271000China Qixia Rural Economic Management Service Center Qixia 265300China

This paper selected five main producing counties of Yangxin,Guanxian,Feixian,Tengzhou and Licheng in central and western Shandong *** on the basic economic data of pear industry from 2011 to 2020,the cultivation areas,yields,main cultivars,production costs and garden prices of pears in the main producing counties in the past 10 years were analyzed,so as to provide reference for the development of pear industry in Shandong Province.

关键词： Shandong province midwest Pear Industrial economy

Research on Redundancy-based Integrated Train Positioning

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Research on Redundancy-based Integrated Train Positioning