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351.
Air pollution is increasingly recognized as a significant contributor to global health outcomes. A methodological framework for evaluating the global health-related outcomes of outdoor and indoor (household) air pollution is presented and validated for the year 2005. Ambient concentrations of PM2.5 are estimated with a combination of energy and atmospheric models, with detailed representation of urban and rural spatial exposures. Populations dependent on solid fuels are established with household survey data. Health impacts for outdoor and household air pollution are independently calculated using the fractions of disease that can be attributed to ambient air pollution exposure and solid fuel use. Estimated ambient pollution concentrations indicate that more than 80% of the population exceeds the WHO Air Quality Guidelines in 2005. In addition, 3.26?billion people were found to use solid fuel for cooking in three regions of Sub Saharan Africa, South Asia and Pacific Asia in 2005. Outdoor air pollution results in 2.7?million deaths or 23?million disability adjusted life years (DALYs) while household air pollution from solid fuel use and related indoor smoke results in 2.1?million deaths or 41.6?million DALYs. The higher morbidity from household air pollution can be attributed to children below the age of 5 in Sub Saharan Africa and South Asia. The burden of disease from air pollution is found to be significant, thus indicating the importance of policy interventions.  相似文献   
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353.
我们使用三维波罗的海模型模拟的做法进行了一项波罗的海水团环流的研究.来自北大西洋的咸水经丹麦海峡流入波罗的海,在波罗的海上涌并与从各河流流入的淡水混合形成"波罗的海高盐传送带".我们利用翻转流量函数和拉格朗日轨迹线对来自大贝尔特和厄勒海峡的成水与淡水的混合情况进行了调查.该翻转流量函数被作为一种具有4个不同垂直坐标(深度、盐度、温度和密度)的函数进行计算,以便了解水的路径以及它在什么地方上涌并混合.在波罗的海本体内发现了与南大洋中的迪肯环流(Deacon Cell)类似的虚拟深度翻转环流的存在,它与哥特兰岛附近的旋转环流相符,当翻转流量函数投射在密度层上时,这一虚拟深度翻转环流就消失了.我们已经开展了一项拉格朗日轨迹线研究,以便更好地认识该环流以及咸水与淡水的混合情况.对这些水团在波罗的海中的停留时间的计算结果为26~29年,而拉格朗日扩散在5年后达到海盆饱和.  相似文献   
354.
Objective Cell free foetal DNA (cff DNA) extracted from maternal plasma is now recognized as a potential source for prenatal diagnosis but the methodology is currently not well standardized. To evaluate different manual and automated DNA extraction methods with a view to developing standards, an International Workshop was performed. Methods Three plasma pools from RhD-negative pregnant women, a DNA standard, real-time-PCR protocol, primers and probes for RHD were sent to 12 laboratories and also to one company (Qiagen, Hilden, Germany). In pre-tests, pool 3 showed a low cff DNA concentration, pool 1 showed a higher concentration and pool 2 an intermediate concentration. Results The QIAamp DSP Virus Kit, the High Pure PCR Template Preparation Kit, an in-house protocol using the QIAamp DNA Blood Mini Kit, the CST genomic DNA purification kit, the Magna Pure LC, the MDx, the M48, the EZ1 and an in-house protocol using magnetic beads for manual and automated extraction were the methods that were able to reliably detect foetal RHD. The best results were obtained with the QIAamp DSP Virus Kit. The QIAamp DNA Blood Mini Kit showed very comparable results in laboratories that followed the manufacturer's protocol and started with ≥ 500 µL plasma. One participant using the QIAamp DNA Blood Midi Kit failed to detect reliably RHD in pool 3. Conclusions This workshop initiated a standardization process for extraction of cff DNA in maternal plasma. The highest yield was obtained by the QIAamp DSP Virus Kit, a result that will be evaluated in more detail in future studies. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
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The Bali Action Plan as adopted under the United Nations Framework Convention on Climate Change (UNFCCC) in 2007, states that Annex I (developed) countries should reduce their greenhouse gas emissions, based on comparable efforts. Within this context, we have explored various comparable effort approaches (for example, equal marginal abatement costs for all countries) for reducing emissions by the year 2020 for individual countries and regions. In all calculations, the total reduction for Annex I countries as a group is assumed to be 30% below 1990 levels. In the analysis, we compare the reduction targets as calculated from the different approaches with the emission reductions as pledged by these countries as part of the Copenhagen Accord, as drafted under the UNFCCC in 2009. Our analysis indicates that the different elements in these calculations may cause a diversity in outcomes and that, therefore, individual countries may favour certain elements over others. These elements include (a) the choice of the approach itself (the same approach may produce very different outcomes for countries with diverging national circumstances, such as Canada and Russia); (b) the reference year (such as 1990 or 2006 emissions, is very important for countries with an increase in emissions since 1990 (e.g. the United States, Canada) or for those that have lower emission levels (e.g. Russia, the Ukraine)); and (c) rules on land use (these are important for countries with large forest areas). It should be noted that the stringency of the individual countries’ reductions as pledged, differs substantially from the stringency of the reduction targets calculated from the effort-sharing approaches. The current pledges by both the European Union and the United States, are lower than the reductions that would be obtained in the effort-sharing approaches for a 30% overall reduction in Annex I countries.  相似文献   
357.
The characterization of contaminated sites can benefit from the supplementation of direct investigations with a set of less invasive and more extensive measurements. A combination of geophysical methods and direct push techniques for contaminated land characterization has been proposed within the EU FP7 project ModelPROBE and the affiliated project SoilCAM. In this paper, we present results of the investigations conducted at the Trecate field site (NW Italy), which was affected in 1994 by crude oil contamination. The less invasive investigations include ground-penetrating radar (GPR), electrical resistivity tomography (ERT), and electromagnetic induction (EMI) surveys, together with direct push sampling and soil electrical conductivity (EC) logs. Many of the geophysical measurements were conducted in time-lapse mode in order to separate static and dynamic signals, the latter being linked to strong seasonal changes in water table elevations. The main challenge was to extract significant geophysical signals linked to contamination from the mix of geological and hydrological signals present at the site. The most significant aspects of this characterization are: (a) the geometrical link between the distribution of contamination and the site’s heterogeneity, with particular regard to the presence of less permeable layers, as evidenced by the extensive surface geophysical measurements; and (b) the link between contamination and specific geophysical signals, particularly evident from cross-hole measurements. The extensive work conducted at the Trecate site shows how a combination of direct (e.g., chemical) and indirect (e.g., geophysical) investigations can lead to a comprehensive and solid understanding of a contaminated site’s mechanisms.  相似文献   
358.
Biological infestations in forests, e.g. the insect outbreaks, have been shown as favoured by future climate change trends. In Europe, the European spruce bark beetle (Ips typographus L.) is one of the main agents causing substantial economic disturbances in forests. Therefore, studies on spatio-temporal characterization of the area affected by bark beetle are of major importance for rapid post-attack management. We aimed at spatially detecting damage classes by combining multidate remote sensing data and a non-parametric classification. As study site served a part of the Bavarian Forest National Park (Germany). For the analysis, we used 10 geometrically rectified scenes of Landsat and SPOT sensors in the period between 2001 and 2011. The main objective was to explore the potential of medium-resolution data for classifying the attacked areas. A further aim was to explore if the temporally adjacent infested areas are able to be separated. The random forest (RF) model was applied using the reference data drawn from high-resolution aerial imagery. The results indicate that the sufficiently large patches of visually identifiable damage classes can be accurately separated from non-attacked areas. In contrast to those, the other mortality classes (current year, current year 1 and current year 2 infested classes) were mostly classified with higher commission or omission errors as well as higher classification biases. The available medium-resolution satellite images, combined with properly acquired reference data, are concluded to be adequate tools to map area-based infestations at advanced stages. However, the quality of reference data, the size of infested patches and the spectral resolution of remotely sensed data are the decisive factors in case of smaller areas. Further attempts using auxiliary height information and spatially enhanced data may refine such an approach.  相似文献   
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