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191.
Forty percent of pregnant women aged 37 years and over do not have prenatal diagnosis despite being eligible for a free test. The present study aimed to determine how often, and which, untested women were making a choice about this, how many declined an offer and why. A questionnaire was given to untested women, aged 37 years and over, at no less than 24 weeks gestation. A total of 375 (81.5%) women declined, 72 (16%) were not offered a test and 13 presented too late antenatally. There was a three-fold increased likelihood (OR 3.10 95% CI 1.44, 6.65) of no offer for urban non-English speaking background women, compared with the reference group (metropolitan, English speaking). Unpartnered women were also significantly less likely to receive an offer (OR 3.18, 95% CI 1.19, 8.46). Risk to the baby was the main reason for declining. When offered non-invasive prenatal screening, most decliners of prenatal diagnosis accepted, even those who declined because they were opposed to abortion. We estimate that overall 33% of older pregnant women were being offered and declining amniocentesis and/or chorion villus sampling (CVS). Only 6% were not offered a test, but this small proportion is over-represented by minority groups who must be given equal opportunity to make this choice. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
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193.
Municipal waste management in the UK has undergone rapid transformation in recent years in pursuit of greater sustainability. In this paper we explore the environmental justice issues and tensions involved in this shift. After a brief overview of environmental justice debates and how they have been related to issues of waste management, we describe how the policies and processes underlying the transformation from an overwhelming dependence on landfill disposal towards more sustainable methods of management has been driven by European legislation embodying principles premised on fundamental environmental concerns of inter- and intra-generational equity. We analyse the key means through which these principles have been translated to restructure local authority practices and the environmental justice issues arising from the implementation of international policy in regional and local context. Finally, we reflect on the implications of this case study for implementation of policies intended to advance both sustainability and environmental justice.  相似文献   
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195.
This paper investigates the ability of peanut hulls and peanut hull pellets to adsorb copper from dilute aqueous metal ion solutions in batch and fixed bed systems. The kinetics of copper uptake onto the media have been investigated in batch systems and the influence of pH and particle size on the rate and extent of copper capture determined. The Langmuir and Freundlich isotherm theories were determined; the Langmuir model was found to best represent the equilibrium isotherm data. In normalized kinetic tests at least 75% of copper removal occurred within the first 20 min; 92% removal was effected within the first 50 min. The rate of uptake was optimum within the pH range 5-7.5, and media capacities remained relatively constant at a pH above 4.0. Bench-scale column studies were performed using peanut hull pellets. The overall capacity of pelletized peanut hulls was higher than for unmodified peanut hulls. Due to their demonstrated ability for Cu(II) uptake and favorable structural characteristics, pelletized peanut hulls could gain use as a low-cost, once-through biomass filter medium for copper-bearing waste streams.  相似文献   
196.
Yellowstone National Park visitor data were obtained from a survey collected for the National Park Service by the Park Studies Unit at the University of Idaho. Travel cost models have been conducted for national parks in the United States; however, this study builds on these studies and investigates how benefits vary by types of visitors who participate in different activities while at the park. Visitor clusters were developed based on activities in which a visitor participated while at the park. The clusters were analyzed and then incorporated into a travel cost model to determine the economic value (consumer surplus) that the different visitor groups received from visiting the park. The model was estimated using a zero-truncated negative binomial regression corrected for endogenous stratification. The travel cost price variable was estimated using both 1/3 and 1/4 the wage rate to test for sensitivity to opportunity cost specification. The average benefit across all visitor cluster groups was estimated at between $235 and $276 per person per trip. However, per trip benefits varied substantially across clusters; from $90 to $103 for the “value picnickers,” to $185–$263 for the “backcountry enthusiasts,” $189–$278 for the “do it all adventurists,” $204–$303 for the “windshield tourists,” and $323–$714 for the “creature comfort” cluster group.  相似文献   
197.
Governments, NGOs, and natural scientists have increased research and policy-making collaborations with Indigenous peoples for governing natural resources, including official co-management regimes. However, there is continuing dissatisfaction with such collaborations, and calls for better communication and mutual learning to create more “adaptive” co-management regimes. This, however, requires that both Western and Indigenous knowledge systems be equal participants in the “co-production” of regulatory data. In this article, I examine the power dynamics of one co-management regulatory regime, conducting a multi-sited ethnography of the practices of researching and managing one transnational migratory species, greater white-fronted geese (Anser albifrons frontalis), who nest where Koyukon Athabascans in Alaska, USA, practice subsistence. Analyzing the ethnographic data through the literatures of critical geography, science studies and Indigenous Studies, I describe how the practice of researching for co-management can produce conflict. “Scaling” the data for the co-management regime can marginalize Indigenous understandings of human–environment relations. While Enlightenment-based practices in wildlife biology avoid “anthropomorphism,” Indigenous Studies describes identities that operate through non-modern, deeply imbricated human–nonhuman identities that do not separate “nature” and “society” in making knowledge. Thus, misunderstanding the “nature” of their collaborations causes biologists and managers to measure and research the system in ways that erase how subsistence-based Indigenous groups already “manage” wildlife: by living through their ethical commitments to their fellow beings. At the end of the article, I discuss how managers might learn from these ontological and epistemological differences to better “co-produce” data for co-management.  相似文献   
198.
Anthropogenically derived 14C has been used to trace recent carbon input in a study of carbon accumulation and turnover in Canadian soils. In order to do so, documentation of the undisturbed nature of the soil horizons sampled was of prime concern. Although all the sites chosen for coring were currently uncultivated, detailed information on long-term land usage was not available. To overcome this problem, 137Cs profiles were measured in all the cores used in the study. 210Pb measurements were also made in cases where total 137Cs deposition was lower than predicted. For some sample sites, the data obtained showed correlated losses of both radionuclides, indicating that land disturbance and/or erosion had indeed occurred in these areas over the past 50 years, hence invalidating the use of those cores for carbon cycling studies. In a few cases a marked lack of correlation between these two radionuclides has made it necessary to hypothesize that chemical, rather than physical, processes have been partially responsible for the observed anomalies. Since results of this nature raise doubts about the reliability of the 137Cs method for identification of land disturbance, further investigation is warranted.  相似文献   
199.
A patient is described who had three consecutive fetuses with cystic hygroma and hydrops, two of which had documentation of normal karyotype. Some twenty percent of fetuses with cystic hygroma have a normal karyotype, and many of these have other major malformations. An autosomal recessive pattern of inheritance has been postulated, but cystic hygroma may also occur is association with a variety of syndromes, some of which have other patterns of inheritance.  相似文献   
200.
Impact of land use on soluble organic nitrogen in soil   总被引:1,自引:0,他引:1  
Although it has been hypothesized that soluble organic nitrogen (SON) plays a central role in regulating productivity in some terrestrial ecosystems, the factors controlling the size of the SON pool in soil remain poorly understood. Therefore our principal aim in this work was to assess the impact of seven different land use systems (rough and managed grassland, deciduous and coniferous woodland, heathland, wetland and tilled land) on the size of the SON and inorganic N (NO? 3, NH+ 4) pools in the surface soil layer (0–15 cm). After extraction with deionised water, we found that in most cases the size of the water extractable organic N (WEON) pool was similar in size to the inorganic N pool. In contrast, the KCl extractable organic N (KClEON) pool constituted the dominant form of soluble N in soils under all land uses, perhaps indicating that significant amounts were held on the soil exchange phase. In contrast to inorganic N, which varied significantly with land use, the size of the KClEON and WEON pool was similar for all land uses with the exception of KClEON in tilled land, where significantly lower amounts were observed. We conclude that SON constitutes an important soil N pool in a broad range of land uses, and that its role in microbial N assimilation, plant nutrition and ecosystem responses to atmospheric N deposition warrants further attention.  相似文献   
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