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31.
Climate Change Projections for the United States Midwest   总被引:1,自引:0,他引:1  
Environmental and societal factors such asair quality, water quality andavailability, land use changes andexpanding urbanization are alreadyaffecting human health and welfare,agriculture, and natural ecosystems in theMidwestern United States. Over thiscentury, these existing stresses willlikely be exacerbated by climate changesresulting from human activities. It isessential that policy decisions aimed atpreserving the well-being of a region beinformed by a good understanding of theregion's climate, how climate might change,and the uncertainties inherent in futureprojections. Recent updates in climatemodeling expertise and an expanded view ofpossible non-intervention emissionscenarios have narrowed the range of changethat can be expected over the Midwestthroughout the next century in some ways,while broadening it in others. In contrastto previous studies, which generallyconsider a mid-range scenario for futureemissions, this study presents the range ofchange that would result from low to highscenarios for climate change. In this waywe account for uncertainties inanthropogenic forcing on climate change inthe region and quantify the potentialeffects of human actions on future climate.This analysis also combines the latestclimate model projections with historicalrecords of observed climate over the pastcentury, effectively placing potentialchanges in extreme event frequencies suchas heavy rainfall events and temperaturethreshold exceedances within the context ofobserved variability over the past century.The purpose of this study is to provide anupdated picture of the potential impacts ofclimate change on the Midwest to inform theimpact assessment and policy developmentcommunity. From the magnitude of thechanges projected by this study, it isclear that these must be included in futurepolicy decisions in order to ensure thesuccessful adaptation and survival ofexisting human and natural systems in theMidwest.  相似文献   
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We have determined the congener compositions of nine commercial Aroclor products of polychlorinated biphenyls (PCBs) to the sub-part-per-million level using high-resolution gas chromatography combined with high-resolution mass spectrometry according to US Environmental Protection Agency (EPA) Method 1668A. These Aroclor composition data should allow improved characterization and risk assessment of PCB contamination at hazardous waste sites, particularly for dioxin-like PCB congeners. By combining the data on the concentrations of each dioxin-like congener with its World Health Organization toxicity equivalency factor, we have established dioxin toxic equivalent concentrations for each pure Aroclor product.  相似文献   
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The prenatal diagnosis of achondrogenesis in association with cystic hygroma is described. Ultrasound findings of severe short-limbed dwarfism, decreased vertebral ossification, and normal ossification of the calvarium were all consistent with achondrogenesis type II. Although the unusual finding of associated cystic hygroma raised the suspicion of a concurrent chromosome abnormality, the karyotype of both fetal lymphocytes and fetal fibroblasts was normal. Autopsy confirmed dilated lymphatic channels in the basal endothelial layer of the skin, cystic hygroma, and coarctation of the aorta. Although previously unreported, we suggest that the features of this case of achondrogenesis indicate an association with lymphatic stasis and jugular lymphatic obstruction sequence in this syndrome.  相似文献   
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Objective

Understanding the value, benefits and harms of health interventions is needed to inform best practice and ensure responsible implementation of new approaches to patient care. Such value is demonstrated through the assessment of outcomes; however, which outcomes are assessed is often highly varied across studies and can hinder the ability to draw robust conclusions. The Core Outcome Development for Carrier Screening study aims to understand the outcomes that can meaningfully capture the value of reproductive genetic carrier screening (RGCS).

Method

The authors report an iterative, two-round online Delphi survey of Australian and New Zealand stakeholders to determine the degree of consensus regarding the core outcomes of RGCS. Panellists ranked 83 outcomes according to their perceived importance on a nine-point Likert scale. Using the distribution of rankings, outcomes were grouped into tiers representative of their perceived level of importance and agreement between groups.

Results

The top tier outcomes represent those agreed to be critically important for all future studies of RGCS to assess and were used to define a preliminary core outcome set encompassing the domains (1) primary laboratory outcomes, (2) pregnancy outcomes, (3) resource use and, (4) perceived utility of RGCS.

Conclusion

These findings can guide the selection of meaningful outcomes in studies aiming to demonstrate the value of RGCS. A future international consensus process will expand on these findings and guide the inclusion of diverse perspectives across the range of settings in which RGCS is offered.  相似文献   
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Survey participants (N=175) were drawn from six branches of a major British supermarket chain. Employees from three branches, who had been selected for transfer to new stores, were surveyed before and after relocation to examine the impact of this transition on individual well‐being. A comparison sample of employees, drawn from similar stores but not involved in relocation, was also surveyed. Cross‐sectional multiple regression analyses found that psychological distress was related to both work demands and personal characteristics (gender, neuroticism, locus of control, and social desirability response). Furthermore, path analysis revealed that after controlling for prior symptom levels, distress during the relocation period was predicted independently by the relocation and by work demands. Although in the present study it was not possible to account for differences in outcomes between new and comparison store employees in terms of changes in measured work characteristics, the negative impact of relocation was found to be buffered by perceptions of control and social support. Additionally, the impact of high work demands was buffered by Type B personal characteristics. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   
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In 2001, 28 acres of the bottom of Ward Cove, AK (USA) were remediated using thin layer placement, to enhance the natural recovery of contaminated sediments. The remediated areas were part of an 80-acre area of concern identified offshore from the site of a former sulfite pulp mill. The primary chemicals of concern were those commonly associated with organic enrichment near pulp mills: ammonia and 4-methylphenol. The primary remedial objectives were to reduce the toxicity of the contaminated sediments and to stimulate colonization of the remediated areas by benthic macroinvertebrates. In 2004, the initial monitoring event for the remediated areas was conducted, and included evaluations of physical/chemical sediment variables (i.e., total organic carbon, grain size distribution, ammonia, and 4-methylphenol), sediment toxicity (i.e., using the 10-day amphipod survival test with Eohaustorius estuarius), and in situ benthic macroinvertebrate communities. Results of the monitoring event showed that conditions in the remediated areas had improved considerably in the 3 years since thin layer placement had occurred. At most stations, concentrations of both ammonia and 4-methylphenol were very low, and amphipod survival was >or=90%. In addition, benthic macroinvertebrates appeared to be rapidly colonizing the remediated areas, based on evaluations of several community metrics (i.e., taxa richness, diversity, and dominance), as well as key indicator species of organic enrichment and associated transitional areas (i.e., primarily the polychaetes Capitella capitata and Nephtys cornuta, and the bivalve molluscs Axinopsida serricata and Parvilucina tenuisculpta). In general, colonization was consistent with the patterns identified for areas recovering from organic enrichment on the continental shelf of southern California and elsewhere. Based on these results, thin layer placement was considered successful in enhancing the natural recovery of the remediated sediments in Ward Cove.  相似文献   
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