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211.
Implementing the UNCCD: Participatory challenges   总被引:1,自引:0,他引:1  
The United Nations Convention to Combat Desertification (UNCCD) emphasizes the need for public participation in land degradation assessment and rehabilitation. While participatory approaches are supported by a growing body of research and practice, meaningfully involving the people affected by land degradation is far from straightforward. This paper investigates the challenge of using the UNCCD as a guide to influence community participation in policy‐making and practice at national and local levels by analyzing experiences from three southern African countries. We show that the UNCCD represents a useful normative framework for addressing degradation problems, but that the participatory ethos is difficult to enact at the national level. Whilst there is increasing evidence that combining local and scientific knowledge using participatory mechanisms can deliver the benefits that the Convention strives to achieve, communication between researchers and practitioners, and those involved in implementing the UNCCD at the national level needs to be strengthened. Broad lessons and best practices in incorporating participatory practices into policy development are elucidated. Our case studies show that a range of mixed‐method, interdisciplinary approaches can enable policy‐makers and practitioners to meaningfully engage those who are affected by land degradation in its definition, assessment and rehabilitation.  相似文献   
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Both exposures to toxic metals, as well as deficiencies in essential metals, during pregnancy has been linked to a variety of negative reproductive outcomes. The exact etiologies of such outcomes and the effects of fetal exposure to these metals are largely unknown. Therefore, the ability to assess levels of these elements is critical to determining the underlying causes of such conditions and the effects that both essential and nonessential metals have on fetal development. Thus, using cell-free fetal RNA from amniotic fluid, we set out to measure the association between amniotic fluid levels of toxic and essential metals and fetal gene expression. We find that arsenic was associated with increased expression of 3 genes known to play roles in both birth-related and reproductive effects. The results highlight the potential for detrimental health effects of prenatal metals exposure and the potential to identify biomarkers of environmental exposure during this critical developmental period.  相似文献   
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Objectives To validate the use of Real Time PCR, a widely used technique that can detect very low levels of Y chromosomal sequence, and to assess the use of a highly sensitive PCR technique, pyrophosphorolysis-activated polymerisation (PAP), for fetal sex determination using free fetal DNA (ffDNA). Methods The fetal sex was determined by Real Time PCR in 58 pregnancies using ffDNA isolated from maternal plasma. In parallel with the Real Time PCR experiments, the presence of Y chromosome sequence was also determined using PAP on 54 isolated ffDNA samples. Results Both techniques detected Y chromosome sequence at very low levels with 98% specificity and 100% sensitivity (Real Time n = 44, PAP n = 54). Furthermore, the PAP technique was shown to be more robust than the Real Time PCR as none of the samples tested failed to meet the acceptance criteria. Combining the two techniques for male fetal sex detection from maternal blood plasma increases the sensitivity and specificity to 100% in this series. Conclusions This study shows that both Real Time PCR and PAP can be used for Y chromosome detection on ffDNA. Furthermore, by using PAP in combination with Real Time PCR more reliable early prenatal sexing can be performed using ffDNA. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
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A method was developed for the risk assessment of a military waste site. The method consists of two steps: 1. evaluation of the exposure through different pathways and 2. derivation of substance-specific tolerable intake levels. In this first part of the paper the quantitative exposure analysis will be discussed. Exposure depends on the conditions at the contaminated site (e.g. soil characteristics), the type of utilisation (residential area, industrial area etc.) and the substance properties. In a specific utilisation scenario, e.g. as residential area, different exposure pathways are contributing to the total contaminant uptake. Because of the properties of nitroaromatic compounds like 2,4,6-trinitrotoluene (good resorption through skin and accumulation in plants) exposure via dermal soil contact and via consumption of plants gains special importance. With these two exposure pathways as examples we explain the quantification of the exposure through different pathways by so-called exposure factors. By comparing the total exposure with tolerable intake levels for the compounds, waste site specific soil pollutant levels can be established (see second part of the paper in UWSF 6/94).  相似文献   
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Sport and active recreation, as an important area of leisure activity that can take place in the countryside, has recently been the subject of much discussion both in central government reports and statutory agencies' studies. This paper examines principles for their planning and management, particularly in sensitive areas such as National Parks, Areas of Outstanding Natural Beauty and Sites of Special Scientific Interest. It takes the view that effective recreation management should be promoted, suggesting that the designation of countryside areas should not imply that they are unchanging, or that environmental policies should be applied uniformly. The Government's UK Sustainable Development Strategy 1994 emphasizes the importance of assessing capacity and of management and monitoring in providing for leisure. Yet knowledge of recreation impacts is incomplete. A number of principles for the management of countryside recreation are given, and examples given of such principles in use. These stress the need for effective participation by the various interests involved at sites and the importance of voluntary approaches to the resolution of conflicts.  相似文献   
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