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Individual and joint exposures to PMconstituents and mortality risk among the oldest-old in china

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Science china Life {1. 2024年

作者： Yaqi Wang Yang yuan Shaocai Mo Fang Wang Jing Wei Yao Yao Yi Zeng Yunquan {1. institute of Social Development and Health Management Hubei Province Key Laboratory of Occupational Hazard Identification and Control School of Public Health Wuhan University of Science and Technology Shenzhen Bao'an District Songgang People's Hospital School of Public Health Xuzhou Medical University Department of Atmospheric and Oceanic Science Earth System Science Interdisciplinary Center University of Maryland College Park china Center for Health Development Studies Peking University Center for Healthy Aging and Development Studies National School of Development Peking University

Cohort evidence linking long-term survival of older adults with exposure to fine particulate matter (PM2.5) constituents remains scarce in *** constructing a dynamic cohort based on the chinese Longitudinal Healthy Longevity Study,we aimed to assess the individual and joint associations of major PM2.5constituents with all-cause death in chinese oldest-old （≥80 years） ***-dependent Cox proportional hazards models were adopted to estimate death risks of long-term exposure to *** 1.,884 participants,totaling 56,3.2 person-years of follow-up,1.,3.6 deaths were *** highest mortality risk associated with an interquartile range（IQR） increase in exposure was 1.081.（95%confidence interval[CI]:1.055–1.1.8） for sulfate (IQR=4.1.g m–3.,followed by 1.078 （95%CI:1.056–1.1.1. for black carbon (IQR=1.6μg m–3.,1.056 （95%CI:1.028–1.084） for ammonium (IQR=3.2μg m–3.,1.050 （95%CI:1.021.1.080） for nitrate (IQR=5.8μg m–3.,and 1.049 （95%CI:1.024–1.074） for organic matter (IQR=1..3.g m–3..In joint exposure,each IQR-equivalent rise of all five PM2.5constituents was associated with an 8.2%（95%CI:4.0%–1..6%） increase in mortality *** weight analysis indicated the predominant role of sulfate and black carbon in driving PM2.5-related *** （aged 80–89 years） and rural dwellers were at significantly greater risk of mortality from individual and joint exposures to *** study suggests that later-life exposure to PM2.5constituents,particularly sulfate and black carbon,may curtail long-term survival of the oldest-old in{3..

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长江上游退耕还林区的土壤退化与肥力重建

山地学报 2000年第6期18卷 526-529页

作者：何毓蓉张丹宫阿都中国科学院、水利部成都山地灾害与环境研究所!四川成都61004.

长江上游退耕还林战略举措的关键技术之一是要模清该区土壤性状和退化问题 ,进而采取行之有效的土壤退化防治措施。尽快恢复生态 ,保护长江安全。以占该区面积最大的紫色土退化为例 ,提出了该区土壤退化特征、类型和发生现状。指出该区... 详细信息

长江上游退耕还林战略举措的关键技术之一是要模清该区土壤性状和退化问题 ,进而采取行之有效的土壤退化防治措施。尽快恢复生态 ,保护长江安全。以占该区面积最大的紫色土退化为例 ,提出了该区土壤退化特征、类型和发生现状。指出该区环境的脆弱性和人为干扰是土壤退化根本成因。建议 :( 1.)建立保护区全面封禁管护 ( 2 )构建网格生物篱保持水土增厚土层 ( {1.加强土壤碳氮物质循环强化培肥 ( 4)分带治土造林建立垄沟种植培肥体系等 ,以达到土壤肥力重建 ,取得退耕还林成效

关键词：退耕还林土壤退化肥力重建长江上游

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四川省毛木耳主要栽培品种出菇比较试验

四川农业大学学报 2004年第4期22卷 353-355页

作者：张丹郑有良王波高健伟谢芝芳四川农业大学农学院四川雅安625014 四川省农科院成都610066 中国科学院水利部成都山地灾害与环境研究所成都610041

报道四川省毛木耳主要栽培品种及一个杂交菌株和一个省外引进菌株的栽培出菇试验 ,试验通过对平均产量鲜重的统计分析、形态特征比较、出菇早晚比较以及干重含量等特性的对照综合分析 ,发现杂交种 3.5菌株是综合特性最好的毛木耳菌株 ,... 详细信息

报道四川省毛木耳主要栽培品种及一个杂交菌株和一个省外引进菌株的栽培出菇试验 ,试验通过对平均产量鲜重的统计分析、形态特征比较、出菇早晚比较以及干重含量等特性的对照综合分析 ,发现杂交种 3.5菌株是综合特性最好的毛木耳菌株 ,产量高、耳片厚、出菇期早。黄耳 1.0号、781.红大耳、上海 1.、95 1.黄背木耳也是目前比较好的栽培菌株 ,但这些菌株的每袋鲜重产量与 3.5有显著差异。

关键词：毛木耳栽培品种出菇试验

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长江上游典型区SOTER数据库支持下的土壤侵蚀危险度评价

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水土保持学报 2003年第5期17卷 48-50页

作者：周红艺何毓蓉张保华陈光辉中国科学院水利部成都山地灾害与环境研究所四川成都610041 彭州市土肥站四川彭州611930

以长江上游典型区彭州市为例,在该区SOTER(1.50000)数据库的支持下,选取地貌类型、坡度、植被覆盖率、土地利用、土壤类型等作为评价因子,运用专家权重模型,将研究区分为无险型、轻险型、危险型、强险型和极险型5种类型,输出了土壤侵... 详细信息

以长江上游典型区彭州市为例,在该区SOTER(1.50000)数据库的支持下,选取地貌类型、坡度、植被覆盖率、土地利用、土壤类型等作为评价因子,运用专家权重模型,将研究区分为无险型、轻险型、危险型、强险型和极险型5种类型,输出了土壤侵蚀危险度评价图,并指出了各种类型的防治侵蚀的措施。

关键词：长江上游土壤侵蚀危险度评价 SOTER

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ASSESSMENT OF SOIL LOSS ON UNCULTIVATED SLOPE LAND BY USING 1.0}CS TECHNIQUE IN THE UPPER YANGTZE RIVER BASIN OF{1.

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International Journal of Sediment Research 2004年第1期19卷 60-65页

作者： Mingyi FENG, Xinbao zhang , Anbang WEN and Xiubin HE{1. West Normal University, Nanchong 63.002, E-mail: mingyifeng2004@*** State Key Laboratory of Soil and Dryland Farming on Loess Plateau, IWSC, CAS, Yangling 71.075 institute of {3. hazards and environment, chinese academy of sciences,chengdu 61004. china West Normal University Nanchong637002 State Key Laboratory of Soil and Dryland Farming on Loess Plateau IWSC CAS Yangling 710075 institute of {1. hazards and {3. Chinese Academy of SciencesChengdu 610041 institute of {1. hazards and {3. Chinese Academy of SciencesChengdu 610041

Radionuclides are used as tracers of sediments in areas where no plot data or field monitoring data are not available. Caesium-1.0} can provide important information on both soil loss rates and sediment sources. The 1.0}Cs technique is employed to assess soil erosion rates in forest and grass lands in the Upper Yangtze River Basin, china. The study area includes 6 forestlands and 4 grasslands in 8 counties and cities over the eastern part of the basin. The 1.0}Cs reference inventories ranged from 620.9 Bq m-2 to 2560.3.Bq m-2. For the 6 forestlands, the average 1.0}Cs inventory over a field ranges from 960.8 Bq m"2 to 2560.3.Bq m-2. The average erosion rate is estimated from the 1.0}Cs measurements between 0 to 588 t km-2yr-1. For the 4 grasslands, the average 1.0}Cs inventory ranges from 1.9.0 Bq m-2 to 869.7 Bq m-2. The average rate of erosion from grassland varies from 0 to 443. t km-2 yr-1. Where the erosion was more severe, the 1.0}Cs inventory was lower. The results showed that there is no clear relation

关键词： Erosion rate Uncultivated land 1.0} Cs technique Upper Yangtze River

All-silicon low-loss THz temporal differentiator based on microring waveguide resonator platform

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Light(Advanced Manufacturing) 2024年第2期5卷 14-23页

作者： Yunjie Rui Shuyu Zhou Xuecou Tu Xu Yan Bingnan Yan Chen zhang Ziyao Ye Huilin zhang Jingya Xie Qing-yuan Zhao La-Bao zhang Xiao-Qing Jia Huabing Wang Lin Kang Jian Chen Peiheng Wu Research institute of Superconductor Electronics(RISE) School of Electronic Science and EngineeringNanjing UniversityNanjingJiangsu 210023China Hefei National Laboratory Hefei 230088China Purple mountain Laboratories NanjingJiangsu 211111China Terahertz Technology Innovation Research institute Shanghai Key Lab of Modern Optical SystemUniversity of Shanghai for Science and TechnologyShanghai200093China

Microring resonators have been widely used in passive optical devices such as wavelength division multiplexers,differentiators,and *** on terahertz(THz)components has been accelerated by these photonics *** and integrated time-domain differentiators that enable low-loss,high-speed THz signal processing are necessary for THz *** this study,an on-chip THz temporal differentiator based on all-silicon photonic technology was *** device primarily consisted of a microring waveguide resonator and was packaged with standard waveguide *** performed time-domain differentiation on input signals at a frequency of 405.45 GHz with an insertion loss of 2.5 dB and a working bandwidth of 0.3. *** periodic waveforms could be handled by this *** device could work as an edge detector,which detected step-like edges in high-speed input signals through differential *** development holds significant promise for future THz data processing technologies and THz communication systems.

关键词： Silicon photonics Whispering gallery mode resonator THz silicon waveguide

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宁南县城后山泥石流综合治理

山地研究 1990年第4期8卷 258-265页

作者：李德基欧阳强王士革中国科学院、水利部成都山地灾害与环境研究所四川省宁南县治理后山泥石流工程指挥部

宁南县城后山有8条泥石流沟。其中3.一旦暴发泥石流,就直接威胁着县城的安全。为使县城免遭泥石流为患,1.85—1.89年县上在有关科研单位参与和支持下,对后山泥石流采取了工程措施、生物措施和预警、管理措施,加以综合治理。治理工程取... 详细信息

宁南县城后山有8条泥石流沟。其中3.一旦暴发泥石流,就直接威胁着县城的安全。为使县城免遭泥石流为患,1.85—1.89年县上在有关科研单位参与和支持下,对后山泥石流采取了工程措施、生物措施和预警、管理措施,加以综合治理。治理工程取得的防灾效益、水保效益与经济效益明显。

关键词：四川省宁南县后山泥石流综合治理

长江上游紫色土坡耕地土壤侵蚀1.0}Cs示踪法研究

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山地学报 2001年第S1期19卷 56-59页

作者：文安邦张信宝王玉宽张一云徐家云白立新中国科学院、水利部成都山地灾害与环境研究所环境研究中心四川大学物理系四川大学物理系四川成都61004.

运用1.3.Cs示踪法对长江上游“长治”水土保持工程重点治理区的云贵高原区、川中丘陵区和三峡库区 8块紫色土坡耕地土壤侵蚀速率研究结果表明 ,影响紫色土坡耕地平均侵蚀速率的主要因子为坡度、坡长、降雨量和土壤粒度组成 ,四个研究区... 详细信息

运用1.3.Cs示踪法对长江上游“长治”水土保持工程重点治理区的云贵高原区、川中丘陵区和三峡库区 8块紫色土坡耕地土壤侵蚀速率研究结果表明 ,影响紫色土坡耕地平均侵蚀速率的主要因子为坡度、坡长、降雨量和土壤粒度组成 ,四个研究区土壤平均侵蚀速率介于 75 8t km2 ·a- 1.～ 985 4t km2 ·a- 1.,计算值与长江上游类似地区径流试验场观测值基本一致。

关键词：紫色土土壤侵蚀速率 1.0}Cs法