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A Systematic Assessment of Blood Lead Level in Children and Associated Risk Factors in China 被引量:6
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作者 WANG Lu LI Zhen +6 位作者 HUANG Shao Xin DU Chuang WANG Hong HE Li Ping BI Yong Yi SHI Yong WANG Chun Hong 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2015年第8期616-619,共4页
In this study, we searched multiple databases for all relevant original articles (1996-2013). To investigate blood lead levels (BLL) and possible risk factors for lead exposure among children in China A total of 388 a... In this study, we searched multiple databases for all relevant original articles (1996-2013). To investigate blood lead levels (BLL) and possible risk factors for lead exposure among children in China A total of 388 articles met our inclusion criteria. The overall geometric mean (GM) BLL was 71 μg/L, and the prevalence of elevated BLL (EBLL, defined as BLL &ge;100 μg/L) was 18.48% among children. The prevalence of EBLL remained significantly higher among boys. In children less than 6 years of age, there were significantly increasing trends in both BLL and prevalence of EBLL in an age-dependent manner. The ban on leaded gasoline significantly reduced the BLL as well as EBLL prevalence; however, children whose parents had lower educational levels or were exposed to lead in the workplace had a higher EBLL prevalence. Despite its decline over time, the average BLL among children in China remains higher than the average level most recently reported in the United States. Childhood lead poisoning remains a public health problem in China. 展开更多
关键词 BLL A Systematic assessment of Blood Lead Level in Children and Associated Risk factors in China
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Assessment on the Two New Factors That Influence China's International Environment
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作者 Jin Canrong 《Contemporary International Relations》 2002年第12期20-26,共7页
The development and changes in international situation after September 11 have exerted complicated influence on China’s external security environment. Therefore, how to judge current international security environmen... The development and changes in international situation after September 11 have exerted complicated influence on China’s external security environment. Therefore, how to judge current international security environment that China faces has become a very hot subject for discussion. 展开更多
关键词 In assessment on the Two New factors That Influence China’s International Environment
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Seed Recalcitrance:a Current Assessment 被引量:4
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作者 宋松泉 Patricia BERJAK +2 位作者 Norman PAMMENTER Tobias M.NTULI 傅家瑞 《Acta Botanica Sinica》 CSCD 2003年第6期638-643,共6页
Seeds have been categorized as orthodox, recalcitrant and intermediate seeds according to their dehydration behaviors. Identification of desiccation-tolerance and -sensitivity of seeds is the basis making storage stra... Seeds have been categorized as orthodox, recalcitrant and intermediate seeds according to their dehydration behaviors. Identification of desiccation-tolerance and -sensitivity of seeds is the basis making storage strategy of seeds and long-term conservation of species gene resources. In addition to the inherent characteristics of the species, developmental status of the seeds, dehydration rate, and the conditions under which they are dried and subsequently re-imbibed are very important factors influencing desiccation tolerance of seeds. Survival, electrolyte leakage rate, and germination/growth rate produced by survived seeds are a excellent synthetic parameter when discussing desiccation tolerance of seeds. Desiccation tolerance of seeds is a quantitative feature. The term 'critical water content' is incorrect and has caused some confusion in assessment of seed recalcitrance. A new working approach to quantify the degree of seed recalcitrance has been proposed in this paper. 展开更多
关键词 DESICCATION-TOLERANCE desiccation-sensitivity orthodox seed recalcitrant seed intermediate seed influence factor and assessment parameter of desiccation tolerance quantitative feature critical water content seed recalcitrance
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Estimation of the behavior factor of existing RC-MRF buildings 被引量:1
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作者 Marco Vona Monica Mastroberti 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2018年第1期191-204,共14页
In recent years, several research groups have studied a new generation of analysis methods for seismic response assessment of existing buildings. Nevertheless, many important developments are still needed in order to ... In recent years, several research groups have studied a new generation of analysis methods for seismic response assessment of existing buildings. Nevertheless, many important developments are still needed in order to define more reliable and effective assessment procedures. Moreover, regarding existing buildings, it should be highlighted that due to the low knowledge level, the linear elastic analysis is the only analysis method allowed. The same codes(such as NTC2008, EC8) consider the linear dynamic analysis with behavior factor as the reference method for the evaluation of seismic demand. This type of analysis is based on a linear-elastic structural model subject to a design spectrum, obtained by reducing the elastic spectrum through a behavior factor. The behavior factor(reduction factor or q factor in some codes) is used to reduce the elastic spectrum ordinate or the forces obtained from a linear analysis in order to take into account the non-linear structural capacities. The behavior factors should be defined based on several parameters that influence the seismic nonlinear capacity, such as mechanical materials characteristics, structural system, irregularity and design procedures. In practical applications, there is still an evident lack of detailed rules and accurate behavior factor values adequate for existing buildings. In this work, some investigations of the seismic capacity of the main existing RC-MRF building types have been carried out. In order to make a correct evaluation of the seismic force demand, actual behavior factor values coherent with force based seismic safety assessment procedure have been proposed and compared with the values reported in the Italian seismic code, NTC08. 展开更多
关键词 seismic behavior existing buildings seismic safety assessment behavior factor
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A stock assessment for Illex argentinus in Southwest Atlantic using an environmentally dependent surplus production model 被引量:3
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作者 WANG Jintao CHEN Xinjun +1 位作者 Kevin W.Staples CHEN Yong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2018年第2期94-101,共8页
The southern Patagonian stock(SPS) of Argentinian shortfin squid, Illex argentinus, is an economically important squid fishery in the Southwest Atlantic. Environmental conditions in the region play an important role... The southern Patagonian stock(SPS) of Argentinian shortfin squid, Illex argentinus, is an economically important squid fishery in the Southwest Atlantic. Environmental conditions in the region play an important role in regulating the population dynamics of the I. argentinus population. This study develops an environmentally dependent surplus production(EDSP) model to evaluate the stock abundance of I. argentines during the period of 2000 to 2010. The environmental factors(favorable spawning habitat areas with sea surface temperature of 16–18°C) were assumed to be closely associated with carrying capacity(K) in the EDSP model. Deviance Information Criterion(DIC) values suggest that the estimated EDSP model with environmental factors fits the data better than a Schaefer surplus model without environmental factors under uniform and normal scenarios.The EDSP model estimated a maximum sustainable yield(MSY) from 351 600 t to 685 100 t and a biomass from 1 322 400 t to1 803 000 t. The fishing mortality coefficient of I. argentinus from 2000 to 2010 was smaller than the values of F(0.1) and F(MSY). Furthermore, the time series biomass plot of I. argentinus from 2000 to 2010 shows that the biomass of I.argentinus and this fishery were in a good state and not presently experiencing overfishing. This study suggests that the environmental conditions of the habitat should be considered within squid stock assessment and management. 展开更多
关键词 Illex argentinus stock assessment Schaefer surplus production model environmental factors Southwest Atlantic
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Assessing the vulnerability of changing coasts,Hainan Island,China 被引量:3
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作者 WANG Yaping SHI Benwei +6 位作者 ZHANG Liang JIA Jianjun XIA Xiaomin ZHOU Liang YU Rui YANG Yang GAO Jianhua 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第4期114-120,共7页
Knowledge of coastline changes and vulnerability is of great importance to local government departments that are responsible for the management and development of coastal zones.To study the nature of change and vulner... Knowledge of coastline changes and vulnerability is of great importance to local government departments that are responsible for the management and development of coastal zones.To study the nature of change and vulnerability along the coasts of the Hainan Island,we collected a large number of sediment samples through the last few years,and reconstructed the changes of the coastline by combining the data of sediment grain-size analysis and the nautical charts/TM RS imaginary.Contrary to being almost free from erosion(as expected from the findings that the coastlines are in a relatively stable state),four major cities in Hainan(i.e.,Haikou,Wenchang,Sanya and Changjiang) turned out to be suffered from a moderate coastal vulnerability primarily because of the large populations that impose considerable pressure on the coastlines.Thus,the assessment methodology utilized in this study,including both anthropogenic and natural factors,serves as a useful tool to obtain a comprehensive understanding of coastline vulnerability for local government,in terms of coastal management and adaptation. 展开更多
关键词 coastline changes vulnerability assessment human and natural factors Hainan Island
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Mobility of toxic metals in sediments: Assessing methods and controlling factors 被引量:7
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作者 Yanbin Li Yong Cai 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2015年第5期203-205,共3页
Metals and metalloids(termed as metals in this article)are important constituent elements of the earth's crust.A number of metals,if present in excess,are toxic to organisms and therefore they are usually defined a... Metals and metalloids(termed as metals in this article)are important constituent elements of the earth's crust.A number of metals,if present in excess,are toxic to organisms and therefore they are usually defined as toxic metals. 展开更多
关键词 Mobility of toxic metals in sediments Assessing methods and controlling factors
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Impact of environmental factors on water quality at multiple spatial scales and its spatial variation in Huai River Basin, China 被引量:8
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作者 XIA Jun WANG LongFeng +4 位作者 YU JingJie ZHAN CheSheng ZHANG YongYong QIAO YunFeng WANG YueLing 《Science China Earth Sciences》 SCIE EI CAS CSCD 2018年第1期82-92,共11页
Quantitative assessment of water quality and its spatial variation identification, as well as the discernment of primary factors affecting water quality are in its urgent in water environment management. In this study... Quantitative assessment of water quality and its spatial variation identification, as well as the discernment of primary factors affecting water quality are in its urgent in water environment management. In this study, four key water quality indicators,namely, ammonia nitrogen(NH_4^+-N), permanganate index(COD_(Mn)), total phosphorus(TP) and total nitrogen(TN) at 71 sampling sites were selected to evaluate water quality and its spatial variation identification. More concerns were emphasized on the anthropogenic factors(land use pattern) and natural factors(river density, elevation and precipitation) to quantify the overall water quality variations at different spatial scales. Results showed that the Yi-Shu-Si River sub-basin had a better water quality status than the Huai River sub-basin. The moderate polluted area nearly distributed in the upper and middle reaches of the Shaying River and Guo River. The high cluster centers which were surrounded with COD_(Mn), NH_4^+-N, TN and TP mainly also distributed in the upper and middle reaches of the Shaying River and Guo River. Redundancy analysis showed that the 200 m buffer area acted as the most sensitive area, which was easily subjected to pollution. The precipitation was identified as the most important variables among all the studied hydrological units, followed by farmland, urban land or elevation. The point source pollution was still existed although the non-point source pollution was also identified. The urban surface runoff pollution was severer than farmland fertilizer loss at the sub-basin scale in flood season, while the farmland showed "small-scale" effects for explaining overall water quality variations. This research is helpful for identifying the overall water quality variations from the scale-process interactions and providing a scientific basis for pollution control and decision making for the Huai River Basin. 展开更多
关键词 Fuzzy comprehensive assessment Environmental factors Moran's I Redundancy analysis Pearson's correlation analysis Huai River Basin
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