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^(14)C dating of moss peat banks in Fildes Peninsula, Antarctica

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Chinese Science Bulletin 1999年第19期44卷 1817-1819页

作者： ZHAO Ye and LI Rongquandepartment of Resource and environmental sciences , {3. Normal university , {3. 100875 , china department of Resource and environmental sciences Beijing Normal University Beijing China

Based on the radiocarbon data of the moss peat banks in Fildes Peninsula, Antarctica, it was calculated that the mean rates of peat accumulation in the upper layer and the lower layer are 0.195 and 0.069 4 mm·a-1 respectively. Based on the radiocarbon date (3.265 ± 120 aBP) and the mean rate of peat accumulation in the lower peat layer, it was calculated that

关键词： Antarctica moss peat bank 14C dating environmental change.

Two possible mechanisms for vortex self-organization

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Science china Earth sciences 2006年第2期49卷 202-211页

作者： LUO Zhexian2, ZHOU Xiuji1 & GAO Shouting3.1. Chinese Academy of Meteorological sciences, beijing 100081, china 2. {3. of Space Information Science, Nanjing university of Information Science and Technology, Nanjing 210044, china 3. Institute of Atmospheric Physics, Chinese Academy of sciences, beijing 100029, china department of environmental Science Nanjing University of Information Science and Technology Nanjing China Chinese Academy of Meteorological sciences Beijing China Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China

The vortex self-organization is investigated in this paper by four groups of numerical experiments within the framework of quasi-geostrophic model, and based on the experimental results two types of possible mechanisms for vortex self-organization are suggested. The meso-scale to-pography may enable separated vortices to merge into a larger scale vortex; and the interaction of meso-γ and meso-β scale systems may make separated vortices to self organize a typhoon-like vor-tex circulation.

关键词： vortex, self-organization, meso-scale topography, interaction of different scales.

A comparative study on Canadian and Chinese river basin planning

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Journal of environmental sciences 1994年第2期6卷 224-233页

作者： Guo Huaicheng (Center of environmental sciences,peking {3., beijing 100871,china)G. Beanlands ( school for Resource & environmental Studies,Dalhousie {3., Halifax, Canada B3. 3.2)

The paper tries to summarize basic approaches to river basin planning in Canada andin china, and makes a comparative analysis taking the Saint John River in Canada and the TaiziRiver in china as examples. The analytical results indicated that policy and management are the ma-jor features of the river basin planning study in Canada; control and treatment of water pollutionhave been generally treated in china; lack of implementation is a common problem in bothcountries.

关键词： river basin planning public participation water pollution.

Anisotropic Variation Law of Rock Permeability with the Burial Depth of Limestone

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Acta Geologica Sinica(English Edition) 2003年第1期77卷 125-128页

作者： TIAN Kaiming, WAN Li and TIAN Jiping department of Water Resources and environmental Science, china {3. of Geosciences,27 Xueyuan Road, beijing 100083. department of Computer sciences, Guangzhou {3., Guangzhou, Guangdong 510091 china Univ Geosci Dept Water Resources & Environm Sci Beijing 100083 Peoples R China Guangzhou Univ Dept Comp Sci Guangzhou 510091 Guangdong Peoples R China

Permeability tensors of both macrofracture and microfracture Systems weremeasured progressively along the depth of limestone formations at severed sites. It was found thatthe principal permeability values K_x, K_y and K_z in these permeability tensors all decreasesimultaneously and logarithmically with depth. However, the limestone aquifers are composed of anupper region where the larger permeability ellipsoid is upright or prolate and characterized byK_z>K_x and K_z>K_y, a transitional zone, and a lower zone whose smaller permeability ellipsoid ishorizontal or oblate and characterized by K_z>K_x and K_z>K_y. The inversion of the permeabilityellipsoids in direction indicates that the anisotropy of rock permeability with the depth oflimestone formations has evidently changed. The anisotropic variation law of permeability tensors ina macrofracture system displays a similar pattern with that in a microfracture system. It is nextto impossible to examine the rock permeability tensor of the aquifer just by measuring the hydraulicparameters of macrofracture system directly, unless the limestone aquifer is exposed on or near theearth's surface. Therefore, the permeability tensors of a macrofracture system at any depth may beindirectly and roughly determined from the gaugeable permeability tensors of the microfracturesystem by conversion. This anisotropic variation law of rock permeability with depth is of greatsignificance in the study of three-dimensional fracture water flow the huge carbonate formations andin the research on the conditions of karst development and karst distribution.

关键词： macrofracture system microfracture system permeability tensor permeability ellipsoid

Carotenoid Analysis of Several Dark-Green Leafy Vegetables Associated With a Lower Risk of Cancers

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Biomedical and environmental sciences 1996年第4期9卷 386-392页

作者： YANG YI HUANG CHENG-YU PENG SHU-SHENG AND LI JIAN (department of Clinical Oncology, Medical Institute of Biorngulation,Kyushu university 69, Beppu 874, Japan school of {3. health, West china university of Medical sciences (WCUMS),Chengdu, china) department of Clinical Oncology Kyushu University Beppu Japan.

We have examined the carotenoid contents of several dark green vegetables found to be associated with a lower risk of various epithelial cancers in our epidemiological study and animal study. Samples of these vegetables were quantitatively examined by highperformance liquid chromatography (HPLC) on a C-18 reversed-phase column for individual carotenoid content. Pure reference compounds (alpha-carotene, beta-carotent, lycopene, canthaxanthin, and lutein) and internal standard (beta-Apo-8'-carotenal) were employed to quantify xanthophylls and carotenes in these vegetables. The results indicated that fresh, dark-green, leafy vegetables were high in beta-carotene (0.94-9.3. mg/100 g) and oxygenated carotenoids or xanthophylls, primarily lutein (0.94-7.3. mg/100 g),whereas lycopene and alpha-carotene were not prominent and canthaxanthin was non existent in these vegetables. These analyses suggest that consumption of carotenoids such as lutein in addition to beta-carotene may be associated with a lower risk of cancers

关键词： Res Am Carotenoid Analysis of Several Dark-Green Leafy Vegetables Associated With a Lower Risk of Cancers

Flow Cytometric Analysis of the Toxicity of Nitrofen in Cultured Keratinocytes

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Biomedical and environmental sciences 1999年第2期12卷 144-149页

作者： YIN LEI JIN XI-PENG YU XIAO-ZHONG AND LIN HUI-FEN(Laboratory of Skin Physiology and Toxicology, school of public health,Shanghai Medical university, Shanghai 20003., china {3. of Dermatology, for City university, for 466, Japan) 上海医科大学公共卫生学院上海 200032 上海医科大学公共卫生学院上海

Lactate dehydrogenase (LDH) release test, 3.H-thymidine (3.H-TdR) and 3.H-leucine (3.H-Leu) incoopration tests and flow cytometric analysis (FCM) of cell cycle were empoyed to elucidate cellular and molecular mechanism of nitrofen-induced toxicity in cultured *** results showed that cell morphologic damages were observed after exposure to 1.0 mmol/L and 10.0 mmol/L nitrofen. LDH release increased in a dose- and time-dependent manner. Depressions in 3. -TdR and 3.H-Leu incorpration were found even at 0.01 mmol/L, and increased with the exposure dose. Cell cycle was analyzed from the DNA- histogram with propidium iodde stain. The results showed that there was no pronounced alteration in cell cycle after cells exposed to 0.01 and 0.1 mmol/L nitrofen. At dose of 1.0 mmol/L, S phase cells increased 2 times of that of control. With the increase of dose, G2/M phase cells became to increase about 5 times of that of the control. At 1 .0 mmol/L, time course of cell cycle after exposure was observed. At the beginning of exposure, cells in S phase and G2/M phase were about 8 .7 % and 11 %. Following 24 h incubation with nitrofen, cells in S phase increased to 18.0% with almost no change in G2/M. 72 h after exposure, G2/M phase cells increased to 63..3.. The forve results demonstrated that S phase and G2/M phase blockage in cultured keratinocytes after exposed to nitrofen seems of importance in the mechanism of nitrofen-induced toxicity.

关键词： Flow Cytometric Analysis of the Toxicity of Nitrofen in Cultured Keratinocytes

Contribution of Root and Microbial Respiration to Soil CO_2 Efflux and Their environmental Controls in a Humid Temperate Grassland of Japan

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Pedosphere 2009年第1期19卷 31-39页

作者： WANG Wei FENG Jiang T. OIKAWA department of Ecology College of Urban and Environmental Sciences and Key Laboratory for Earth Surface Processes of the Ministry of Education Peking University Beijing 100871 （China） school of Urban and environmental sciences Northeast Normal University Changchun 130024 （China） Institute of Biological sciences University of Tsukuba Tsukuba Ibaraki 305-8572 （Japan）

Soil CO2 efflux, root mass, and root production were investigated in a humid temperate grassland of Japan over a growing season （Apr. to Sep.） of 2005 to reveal seasonal changes of soil CO2 efflux, to separate the respective contributions of root and microbial respiration to the total soil CO2 efttux, and to determine the environmental factors that control soil respiration. Minimal microbial respiration rate was estimated based on the linear regression equations between soil CO2 effiux and root mass at different experimental sites. Soil CO2 efflux, ranging from 4.99 to 16.29 μmol CO2 m^-2 s^-1, depended on the seasonal changes in soil temperature. The root mass at 0-10 cm soil depth was 0.82 and 1.27 kg m^-2 in Apr. and Sep., respectively. The root mass at 0-10 cm soil depth comprised 60% of the total root mass at 0-50 cm soil depth. The root productivity at 0-3. cm depth varied from 8 to 180 g m^-2 month^-1. Microbial and root respiration rates ranged from 1.3. to 5.51 and 2.72 to 12.06μmol CO2 m^-2 s^-1, respectively. The contribution of root respiration to the total soil CO2 efflux averaged 53., ranging from 3.% to 72%. The microbial respiration rate was exponentially related to soil temperature at 10 cm depth （R^2 = 0.9400, P = 0.002, n = 6）, and the root respiration rate was linearly related to the root production at 0-3. cm depth （R2 = 0.6561, P = 0.042, n = 6）.

关键词： grasslands microbial respiration root production root respiration

成人高血压合并2型糖尿病和血脂异常基层防治中国专家共识(2024年版)

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中国全科医学 2024年第28期27卷 3453-3475,3482页

作者：北京高血压防治协会中国老年学和老年医学学会北京市社区卫生协会北京社区健康促进会李杰王红姜岳不详首都医科大学附属北京友谊医院北京市东城区朝阳门社区卫生服务中心清华大学第一附属医院全科医学科

高血压、2型糖尿病、血脂异常被统称为“三高”,常同时存在于同一个体中,显著增加了患者的住院和死亡风险,以及相关疾病负担。因此,有必要对三者进行共同风险管理和规范治疗。基层医疗卫生机构是慢性病防治的“主战场”,现有临床证据对... 详细信息

高血压、2型糖尿病、血脂异常被统称为“三高”,常同时存在于同一个体中,显著增加了患者的住院和死亡风险,以及相关疾病负担。因此,有必要对三者进行共同风险管理和规范治疗。基层医疗卫生机构是慢性病防治的“主战场”,现有临床证据对“三高”人群的基层预防、治疗及管理具有重要启示,但目前国内外尚无适用于基层的“三高”共管规范、共识和指南。北京高血压防治协会等4家学/协会组织基层医务人员,并邀请心血管、内分泌、药学及公共卫生等诸多领域专家/学者共同参与,广泛征询基层医务人员临床实践需求,在整合与评价“三高”基层防治相关证据的基础上,经过多轮讨论、修订与投票表决,形成了包含21条推荐意见的“三高”基层防治专家共识。本共识的推荐意见旨在提高基层医务人员的“三高”防治意识和能力,为基层医疗卫生机构开展“三高”防治提供科学的策略支持,为实施具有基层特色的“三高”共管奠定坚实基础。

关键词：高血压糖尿病,2型血脂异常慢性病共病 “三高”防治初级卫生保健专家共识

CHARACTERISTICS OF CHANGE IN TEMPERATURE DURING THE PAST 50 YEARS IN JILIN PROVINCE OF china

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Chinese Geographical Science 2002年第4期12卷 329-332页

作者： ZHAO Xin -yi,WAN Jun,WU Xiu -qin(department of Urban and Environment al sciences,peking {3.,beijing 100871,P.R.china) department of Urban and environmental sciences Peking University Beijing P. R. China

Based on the monthly mean temperatu re,the changing processes and tendencies of temperature during1951-2000in Jilin Province,which i s in Northeast china,are analyzed.A nd the spatial characteristics of th e change are *** the past 50years the te mperature of Jilin Province was increasing just like the other areas in th e *** 1990,the increasing of temperature has been more obvious th an that in the previous *** the west to the east,the province has larger tem perature *** to Principal Component Analysis(PCA)of temperature field,Jilin Province is divided int o 3.egions and the degree of becoming warmer is different from region to re *** the period of 1951to 2000,the annual temperature in Jilin Province has been rising,so has the temperature in winter and *** average temperature in t he 1990s was 0.5-2.0℃higher than that in the *** the west to the east,the increasing of temperature becam e smaller.

关键词： temperature change spatial characteristics jilin province