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| 1 | Estimation of internal nutrient release in large shallow Lake Taihu, China显示文摘Based on field investigation of wave, sediment suspension and the changes in nutrient concentration of the water column in Lake Taihu, China, we proposed two release models to quantify nutrient release under static and dynamic conditions, respectively. Under static conditions, nutrient release from sediments to the overlying water mainly depends on chemical diffusion induced by concentration gradient, in which the nutrient release is controlled by the temperature, dissolved oxygen concentration in the sediment-water interface, oxidation-reduction potential and the concentration difference between porewater and overlying water. Under dynamic condition (or disturbed condition),both dissolved and particulate nutrients in sediments are released into the water column because of wind-induced sediment suspension. The amount of nutrient release under dynamic conditions is larger than that under the static condition. The release of dissolved nutrients, however, does not increase because the wind induced turbulence made oxidation of metallic elements such as Fe (ferric iron), Mn which are capable of precipitating soluble reactive phosphate (SRP). Under dynamic conditions, therefore, the release of total phosphorus (TP) increases dramatically but the release of SRP is close to those under static conditions. In sediments of Lake Taihu, high Fe content leads to a high ratio of Fe to P contents in sediments (Fe:P ratio). Under dynamic conditions, therefore, nutrient release is controlled by the intensity of disturbance, sediment consolidation and nutrient content in sediments.As for dissolved nutrients, especially SRP, the release is also controlled by the intensity of dynamic re-oxidation, Fe content in sediments and nutrient concentration gradient between porewater and overlying water. Based on these two release modes, the release flux in Lake Taihu has been estimated. In the static condition (i.e. laboratory experimental condition), total release of NH4+-N for whole lake is ca. 10,000 ton/a, and PO43--P is ca. 900 ton/a. In the dynamic condition, nutrient release following sediment suspension was estimated according to three different intensities of wind forcing which were defined as 'calm' (wind speed is less than 2 m/s), 'gentle' (wind speed is greater than 2 m/s and less than 6 m/s) and 'gust' (wind speed is greater than 6 m/s). The release rate in the condition of 'calm' was estimated in terms of the nutrient release in the laboratory experimental static condition; whereas the release rate in conditions of 'gentle' and 'gust' was estimated in terms of measurement during sediment resuspension conducted in flume experiments. With the observation of wind velocity and frequency in 2001, each type of wind forcing took the frequency of 12%, 82% and 6% for 'calm', 'gentle' and 'gust', respectively. The yearly release of nitrogen was 81,000 ton and phosphorus was 21,000 ton, which is about 2-6 folds of annual external loading, respectively. | QIN Boqiang, ZHU Guangwei, ZHANG Lu, LUO Liancong, GAO Guang & GU Binhe Nanjing Institute of Geography & Limnology, Chinese Academy of Sciences, Nanjing 210008, China Everglades Department, South Florida Water Management District, 3301 Gun Club Road, West Palm Beach, FL 33406, USA | 2006 | Science China Earth Sciences2006，49，z1： | 37 |
| 2 | 膝关节生长软骨的MR表现特征与微细解剖结构的研究显示文摘目的 :明确正常生长软骨的MR信号特征与细微解剖结构的相关性。方法 :用 1.5TGE全身MR仪对 12例出生 2周的乳猪的双膝关节骨骺进行扫描 ,扫描范围包括二次骨化中心的骨质、二次骨化中心周围的骺软骨、生长板软骨、干骺端。将MR所显示的各层细微解剖结构的信号特征、厚度与相应组织学构造和各层的厚度进行相关性比较对照。结果 :MRI显示了二次骨化中心骨髓和干骺端之间的 5种不同的微解剖结构 :①二次骨化中心的临时钙化带 ;②二次骨化中心的生长板 ;③骨骺软骨 ;④生长板 ;⑤临时钙化带。在SET1WI和T2 WI像上 ,各层不同信号区域的厚度与相对应的微细解剖结构的厚度具有良好的相关性 (r =0 .91)。结论 :MRI能够鉴别骨骺和生长板软骨 ,且与其组织学结构有良好的相关性。 | 李小明 王仁法 张景峰 李勇刚 杨波 Beach R | 2004 | 放射学实践2004，19，4： | 5 |
| 3 | Modeling Climate Change Impacts on the US Agricultural Exports显示文摘Climate change is expected to have substantial effects on agricultural productivity worldwide. However, these impacts will differ across commodities, locations and time periods. As a result, landowners will see changes in relative returns that are likely to induce modifications in production practices and land allocation. In addition, regional variations in impacts can alter relative competitiveness across countries and lead to adjustments in international trade patterns. Thus in climate change impact studies it is likely useful to account for worldwide productivity effects. In this study, we investigate the implications of considering rest of world climate impacts on projections of the US agricultural exports. We chose to focus on the US because it is one of the largest agricultural exporters. To conduct our analyses, we consider four alternative climate scenarios, both with and without rest of world climate change impacts. Our results show that considering/ignoring rest of world climate impacts causes signifi cant changes in the US production and exports projections. Thus we feel climate change impact studies should account not only for climate impacts in the country of focus but also on productivity in the rest of the world in order to capture effects on commodity markets and trade potential. | ZHANG Yu-quan CAI Yong-xia Beach Robert H McCARL Bruce A | 2014 | Journal of Integrative Agriculture2014，13，4： | 3 |
| 4 | Pesticide exposures and respiratory health in general populations显示文摘Human exposures to pesticides can occur in the workplace,in the household and through the ambient environment.While several articles have reviewed the impact of pesticide exposures on human respiratory health in occupational settings,to the best of our knowledge,this article is the first one to review published studies on the association between pesticide exposures and human respiratory health in the general populations.In this article,we critically reviewed evidences up to date studying the associations between non-occupational pesticide exposures and respiratory health in general populations.This article also highlighted questions arising from these studies,including our recent analyses using the data from the Canadian Health Measures Survey(CHMS),for future research.We found few studies have addressed the impact of environmental pesticide exposures on respiratory health,especially on lung function,in general populations.In the studies using the data from CHMS Cycle 1,exposures to OP insecticides,pyrethroid insecticides,and the organochlorine pesticide DDT were associated with impaired lung function in the Canadian general population,but no significant associations were observed for the herbicide 2,4-D.Future research should focus on the potential age-specific and pesticide-specific effect on respiratory health in the general population,and repeated longitudinal study design is critical for assessing the temporal variations in pesticide exposures.Research findings from current studies of non-occupational pesticide exposures and their health impact in general population will help to improve the role of regulatory policies in mitigating pesticide-related public health problems,and thereafter providing greater benefit to the general population. | Ming Ye Jeremy Beach Jonathan W.Martin Ambikaipakan Senthilselvan | 2017 | Journal of Environmental Sciences2017，29，1： | 3 |
| 5 | High school sports programs differentially impact participation by sex显示文摘背景:研究表明,参加体育活动可降低儿童和青少年肥胖的风险。学校是促进儿童和青少年参加体育活动的理想环境,但目前尚不清楚体育活动的'获得'和'选择'如何影响学生的参与度,也不清楚学校体育课的特点对学生参与体育的影响是否存在性别差异。本研究旨在评价高中体育运动项目的特点,并确定这些体育课程对男女生参与运动队的影响程度。方法:用电话采访的方式纵向调查了1,244名新罕布什尔州和佛蒙特州的学生。学生自述他们小学至高中阶段参与运动队的情况。通过调查高中职员了解体育机会。在本研究中,'体育机会'是指每100名学生所对应的学校提供的体育项目种类《选择)和学校提供的体育种类中不限制参加人数的体育项目的比例(获得)。结果:约70%的儿童参加了至少一个体育运动队,男生为73%,女生为66%。研究发现在性别和两个体育机会变量之间存在显著交互影响。控制小学生参与体育活动和其他协变量后,发现如果学校不限制最受欢迎的体育项目的参与人数,男生会参加更多的体育运动队(RR=1.12,p<0.01)。相反,如果学校提供广泛的体育项目,女生会参加更多的体育运动队(RR=1 47,p<0.001)。结论:前人研究表明,参加体育活动能带来许多健康效益。对公共卫生工作包括预防肥胖而言,学校体育课可能是一个重要而有效但未被充分利用的对象。要使青少年参加更多的体育活动,就应综合考虑学校体育项目的获得和选择。学校可运用不同策略,促使男生和女生更多地参加体育活动。 | Keith M. Drake Meghan R. Longacre Todd MacKenzie Linda J. Titus Michael L. Beach Andrew G. Rundle Madeline A. Dalton | 2015 | Journal of Sport and Health Science2015，4，3： | 3 |
| 6 | A new regulatory motif in cell cycle control causing specific inhibition of cyclinD/CDK4显示文摘 | Serrano M Hannon Gj Beach D | | 0，，： | 2 |
| 7 | Colorectal Cancer in Patients Under Close Colonoscopic Surveillance显示文摘 | Douglas J. Robertson E. Robert Greenberg Michael Beach Robert S. Sandler Dennis Ahnen Robert W. Haile Carol A. Burke Dale C. Snover Robert S. Bresalier Gail McKeown-Eyssen Jack S. Mandel John H. Bond Rosalind U. van Stolk Robert W. Summers Richard Rothste | 2005 | Gastroenterology2005，，1： | 2 |
| 8 | pl5INK4B is a potential effector of TGF-beta-induced cell cycle arrest 显示文摘 | Harmon G J Beach D | 1994 | Nature1994，371，6494： | 1 |
| 9 | Optimal training sequences for channel estimation in cyclic-prefix-based single-carrier systems with transmit diversity显示文摘 | Coon J Beach M McGeehan J | 2004 | IEEE Signal Processing Letters2004，11，9： | 1 |
| 10 | CW theory of quasi-three level end-pumped laser oscillators显示文摘 | Beach R J | 1996 | Opt Commun1996，123，： | 1 |
| 11 | The spouse:a factor in recovery after acute myocardial infarction显示文摘 | Beach E K Maloney B H Plocica A R | 1992 | Heart Lung1992，21，1： | 1 |
| 12 | Analysis of an intracavity doubled diode-pumped Q switched Nd:YAG laser producing more than 100 Wofpowerat 532 mm显示文摘 | Honea E C Ebbers C A Beach R J | 1998 | OptLett1998，23，15： | 1 |
| 13 | A highly stereoselective sythesis of anti-HIV 2', 3'-dideoxy-and 2', 3'-didehydro-2', 3'-dideoxynucleosides显示文摘 | Beach WB Kim HO Jeong LK | 1992 | J Org Chem1992，57，14： | 1 |
| 14 | Contemporary in vitro spectrum of activity summary for antimicrobial agents tested against 18569 strains non-fermentative gram-negative bacilli isolated in the SENTRY Antimicrobial Surveillance Program (1997-2001)显示文摘 | Jones R N Sader H S Beach M L | 2003 | Int J Antimicrob Agents2003，22，6： | 1 |
| 15 | Quantitative segmental evaluation of venous valvular reflux with duplex ultrasound scanning 显示文摘 | van Bemmelen PS Bedford G Beach KW | 1989 | J Vasc Surg1989，10，： | 1 |
| 16 | A new regulatory motif in cell-cycle control causing specific inhibition of cyclinD/CDK4显示文摘 | Serrano M Hannon GT Beach D | 1993 | Nature1993，366，6： | 1 |
| 17 | Specific activation of cdc25 tyrosine phosphatases by B-type cyclins:evidence for multiple roles of mitotic cyclins显示文摘 | GALAKTIONOV K BEACH D | 1991 | Cell1991，67，6： | 1 |
| 18 | A review of manufacturing flexibility显示文摘 | Beach R Muhlemann A P Price D H R | 2000 | European Journal of Operational Research2000，122，： | 1 |
| 19 | Gene expression correlates of neurofibrillary tangles in Alzheimer's disease显示文摘 | Dunckley T Beach TG Ramsey KE | 2005 | Neurobiol Aging2005，19，： | 1 |
| 20 | Associated mortality and clinical characteristics of nosocomial Pseudomonas maltophilia in a university hospital显示文摘 | Morrison AJ Sader HS Beach ML | 1986 | J Clin Microbiol1986，24，1： | 1 |
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