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61.
Few disputes in the annals of US environmentalism enjoy the pedigree of the conservation-preservation debate. Yet, although many scholars have written extensively on the meaning and history of conservation and preservation in American environmental thought and practice, the resonance of these concepts outside the academic literature has not been sufficiently examined. Given the significance of the ideals of conservation and preservation in the justification of environmental policy and management, however, we believe that a more detailed analysis of the real-world use and understanding of these ideas is needed. In this paper, we describe the results of a qualitative, semantic study of the concepts of conservation and preservation undertaken in the context of the Chattahoochee National Forest (CNF), located in northern Georgia (USA). Thirty in-depth interviews were conducted with scientists and north Georgia residents either interested or involved in the future management of the forest. Respondents were asked to define conservation and preservation in their own words and to indicate which approach they felt was more appropriate for the management of the CNF. Qualitative content analysis was used to elicit a set of recurring themes for each foundational concept. Taken together, these themes help to flesh out the meaning of conservation and preservation for citizens and scientists today, and illustrate the evolving nature of two of the more significant and venerable ideas animating US environmental policy and management.  相似文献   
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ABSTRACT: The municipal water conservation options available to meet the goals of a national water conservation policy are evaluated. Water conservation with water conservation devices is shown to offer many significant advantages over education and pricing and metering as a method of accomplishing water conservation goals. Current constraints on the use of water conservation devices are outlined, and their elimination is suggested if the nation's water conservation goals are to be met.  相似文献   
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Objectives

To develop a flexible droplet digital PCR (ddPCR) workflow to perform non-invasive prenatal diagnosis via relative mutation dosage (RMD) for maternal pathogenic variants with a range of inheritance patterns, and to compare the accuracy of multiple analytical approaches.

Methods

Cell free DNA (cfDNA) was tested from 124 archived maternal plasma samples: 88 cases for sickle cell disease and 36 for rare Mendelian conditions. Three analytical methods were compared: sequential probability ratio testing (SPRT), Bayesian and z-score analyses.

Results

The SPRT, Bayesian and z-score analyses performed similarly well with correct prediction rates of 96%, 97% and 98%, respectively. However, there were high rates of inconclusive results for each cohort, particularly for z-score analysis which was 31% overall. Two samples were incorrectly classified by all three analytical methods; a false negative result predicted for a fetus affected with sickle cell disease and a false positive result predicting the presence of an X-linked IDS variant in an unaffected fetus.

Conclusions

ddPCR can be applied to RMD for diverse conditions and inheritance patterns, but all methods carry a small risk of erroneous results. Further evaluation is required both to reduce the rate of inconclusive results and explore discordant results in more detail.  相似文献   
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NELUP was a five-year academic research project into interdisciplinary river catchment modelling. The experience of staff involved offers useful insights into the intellectual and practical problems associated with interdisciplinary catchment management research and the dissemination and acceptance of results. In particular, it is suggested that: entrenched academic territories, derived from disciplinary and data differences, make managing an interdisciplinary team of researchers a non-trivial task; data errors, model complexity and model generality masked by a seductively sophisticated-looking DSS risk an illusion of technique; and that acceptance of decision support is hindered by practitionersand policy makers' suspicion of potential automated decision making by default.  相似文献   
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This paper presents the results from a post-auditing study-a comparison of the predictions of environmental impacts of projects made in environmental statements prior to developmentwith those that actually occurred upon or after development. The purpose of post-auditing is to provide an analysis of prediction performance in environmental impact assessment and thus to improve future practice by learning from experience. By means of a combination of site visits, interviews and document scrutiny, 865 predictions from 28 UK projects granted planning permission were examined. Of these, 488 (56%) were auditable, of which 383 (79%) were deemed 'accurate' or 'nearly accurate' and 105 (21%) 'inaccurate'. The remaining 377 (44%) predictions were not auditable, the main reasons being lack of data, vague or ambiguous predictions and time dependency.There were only six unpredicted impacts. The study reveals some encouraging findings, but also a number of discouraging ones, which indicate the need to increase both enthusiasm for, and implementationof, post-auditing activities. Several suggestions are made to help achieve these objectives.  相似文献   
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