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91.
Phthalates are ubiquitous environmental chemicals with potential detrimental health effects. The purpose of our study was to quantify dietary intake of phthalates and of DEHA (Di-ethylhexyl adipate) using duplicate diet samples and to compare these data with the calculated data based on urinary levels of primary and secondary phthalate metabolites. 27 female and 23 male healthy subjects aged 14-60 years collected daily duplicate diet samples over 7 consecutive days. Overall, 11 phthalates were measured in the duplicates by GC/MS and LC/MS methods. Urinary levels of primary and secondary phthalate metabolites are also available. The median (95th percentile) daily intake via food was 2.4 (4.0) microg/kg b.w. (Di-2-ethylhexyl phthalate, DEHP), 0.3 (1.4) microg/kg b.w. (Di-n-butyl phthalate, DnBP), 0.6 (2.1) microg/kg b.w. (Di-isobutyl phthalate, DiBP) and 0.7 (2.2) microg/kg b.w. for DEHA. MEPH (Mono-2-ethylhexyl phthalate) was detectable only in minor concentrations in the samples, thus conversion of DEHP to MEHP and dietary intake of MEHP were negligible. When comparing back-calculated intake data of the DEHP metabolites with dietary DEHP intake from the day before significant correlations were observed for most of the metabolites. No correlation was found for DnBP and only a weak but significant correlation for DiBP. The median and 95th percentile daily dietary intake of all target analytes did not exceed the recommended tolerable daily intake. Our data indicated that food was the predominant intake source of DEHP, whilst other sources considerably contributed to the daily intake of DnBP and DiBP in an adult population.  相似文献   
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The Mediterranean and neighboring countries are already experiencing a broad range of natural and man-made threats to water security. According to climate projections, the region is at risk due to its pronounced susceptibility to changes in the hydrological budget and extremes. Such changes are expected to have strong impacts on the management of water resources and on key strategic sectors of regional economies. Related developments have an increased capacity to exacerbate tensions, and even intra- and inter-state conflict among social, political, ecological and economic actors. Thus, effective adaptation and prevention policy measures call for multi-disciplinary analysis and action.This review paper presents the current state-of-the-art on research related to climate change impacts upon water resources and security from an ecological, economic and social angle. It provides perspectives for current and upcoming research needs and describes the challenges and potential of integrating and clustering multi-disciplinary research interests in complex and interwoven human-environment systems and its contribution to the upcoming 5th assessment report of the IPCC.  相似文献   
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This paper describes concerns about the documentation, dissemination and use of lessons learned from mishap investigations, impediments posed by current practices, and opportunities for improvement. Lessons are presently developed, documented and stored primarily in narrative form and relational databases, and disseminated in many forms and media, including the Internet. Current practices pose many impediments to maximized development, dissemination and use. Investigation process research and new data concepts behind the Semantic Web, exploited elsewhere, offer potential opportunities to overcome these impediments. To exploit these opportunities, formation of a working group to develop an improved Semantic Web-friendly mishap investigation lessons learning system is proposed. An example illustrating an alternative approach is described to support a reasonable expectation that an alternative lessons learning system could be developed.  相似文献   
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The Wanjiazhai Water Transfer Project, now under development by the Shanxi Province of China with World Bank assistance, is a pioneering undertaking providing massive integrated water transfer, to enable the 'parched' regions of northern China to be able to survive. The Wanjiazhai project will deliver some 1.76 million m3/day of fresh water from the Wanjiazhai Reservoir on the Yellow River, by means of a series of pumping stations tunnels, and other components, over a distance of some 285 km to the City of Taiyuan, which is the hub of one of China's major industrial zones. Due to the continuing growth of population and of associated industry and agriculture, the local water resources have become totally overutilised, although extensive recycling for industry and irrigation occurs. The current sustainability of the groundwater resources is seriously threatened, for the present water shortage is 0.43 million m3/day. In addition, because of the large production of pollutant discharges with insufficient attention to waste management, the local river has become grossly polluted. The only answer is a massive importation of water, which is the first step in the project now underway.The focus of the present paper is to examine how the overall project will incorporate essential components to ensure that the expensive imported water will be wisely utilized. To manage this problem the overall project includes a number of special components including: (i) a critical assessment of the new total water resources availability and its allocation between various users, including a pricing structure which assigns equal value to both local and imported water supplies, (ii) an optimization of use of clean technologies and of recycling by industries, as well as improved waste treatment, including the establishment of a financial revolving fund to assist in achieving these goals, (iii) a substantial strengthening of the community/regional water pollution control management operations, with adequate funding, so as to upgrade the municipal wastewater treatment system to restore the river to acceptable water quality levels and, (iv) the recharging of the groundwater basins with treated sewage effluents, plus recharging using floodwater runoff during the rainy seasons.  相似文献   
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对美洲热带湿润低地次生林管理的看法   总被引:7,自引:0,他引:7  
在休闲农地上重新长出的次生林,尽管广被忽视,仍是美洲热带低地重要的景观单元.这些在私人占用土地中"新"的森林资源不是来源于境况较好农民的非持续性的大牧场就是来源于资源贫乏农民的耕种/休闲体系.  相似文献   
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