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41.
Through extensive research, ecosystem services have been mapped using both survey-based and biophysical approaches, but comparative mapping of public values and those quantified using models has been lacking. In this paper, we mapped hot and cold spots for perceived and modeled ecosystem services by synthesizing results from a social-values mapping study of residents living near the Pike–San Isabel National Forest (PSI), located in the Southern Rocky Mountains, with corresponding biophysically modeled ecosystem services. Social-value maps for the PSI were developed using the Social Values for Ecosystem Services tool, providing statistically modeled continuous value surfaces for 12 value types, including aesthetic, biodiversity, and life-sustaining values. Biophysically modeled maps of carbon sequestration and storage, scenic viewsheds, sediment regulation, and water yield were generated using the Artificial Intelligence for Ecosystem Services tool. Hotspots for both perceived and modeled services were disproportionately located within the PSI’s wilderness areas. Additionally, we used regression analysis to evaluate spatial relationships between perceived biodiversity and cultural ecosystem services and corresponding biophysical model outputs. Our goal was to determine whether publicly valued locations for aesthetic, biodiversity, and life-sustaining values relate meaningfully to results from corresponding biophysical ecosystem service models. We found weak relationships between perceived and biophysically modeled services, indicating that public perception of ecosystem service provisioning regions is limited. We believe that biophysical and social approaches to ecosystem service mapping can serve as methodological complements that can advance ecosystem services-based resource management, benefitting resource managers by showing potential locations of synergy or conflict between areas supplying ecosystem services and those valued by the public.  相似文献   
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Elementary schools in four areas of Greater Chattanooga were selected for a study of the effects of community exposure to nitrogen dioxide. One area, in close proximity to a large TNT plant, had high NO2 exposure, another had relatively high suspended particulate exposure, and two areas served as “clean” controls. The similarity of the economic levels of the High-NO2 and Control areas and the moderately lower economic level of the High-Particulate area were documented. Pollutant concentrations for NO2 gas, suspended nitrates and sulfates, total suspended particulates, and soiling index were measured at stations located within the study areas. Ventilatory performance of second-grade school children in the High-NO2 exposure area was significantly lower than the performance of children in the Control areas. The data suggested that ventilatory performance was adversely affected only when an NO2 threshold was exceeded but that above this threshold no further impairment of performance could be detected.  相似文献   
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Near surface disposal facility design and management are examined and compared using a systems approach that defines facility performance as a function of three components (or subsystems): the disposal facility design (cover systems and bottom liners); the properties of the waste (waste composition, waste form and waste package); and the site‐specific environmental features (climate, geology, and hydrology). We report an evaluation of five DOE near surface disposal facility case studies, selected to provide a “representative” sample that included disposal sites with a range of waste and environmental characteristics across the DOE. The facilities selected were the Savannah River E‐Area Engineered Trenches, Hanford Integrated Disposal Facility, Idaho Radioactive Waste Management Complex, Oak Ridge Environmental Management Waste Management Facility, and Nevada National Security Site Area 5. ©2015 Wiley Periodicals, Inc.  相似文献   
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Contamination of amniotic fluid cell cultures by maternal cells can be expected to lead to misdiagnosis of fetal genotype in 0·1 to 0·5/100 cultures, when assays are carried out directly on cultured cells. Chemical analysis of the cell-free amniotic fluid supernatant may overcome this source of error and has the added advantages of speed and independence from amniotic cell culture failure. We describe a pregnancy at risk for Hurler's disease where amniotic cells cultured at amniocentesis had a female karyotype and an α-iduronidase activity towards both phenyl and 4-methylumbelliferyl substrates at the lower end of the normal range, suggesting a heterozygous fetus. An affected fetus was predicted, however, because of a high concentration of dermatan sulphate in the amniotic fluid. The discrepancy between these findings was shown to be due to maternal cell contamination of amniotic fluid cell cultures by the birth of a male infant with Hurler's disease.  相似文献   
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Emeritaanaloga (Crustacea:Hippidae) from three southern California (U.S.A.) beaches contained 0.9 to 24.1 μg/g dry wt saturated hydrocarbons, and 3.6 to 21.4 μg/g dry wt unsaturated hydrocarbons. Major constituents were (in wt. % total): n-alkanes (13.1%), heneicosapentaene plus heneicosahexaene (1.0%), squalene (5.1%), and unidentified polyenes (7.8%). Crabs from beaches exposed to small boat traffic and natural oil seepage were slightly and severely tainted, respectively, with petroleum hydrocarbons. Animals from San Nicolas Island (85 km offshore) contained only biogenic compounds.  相似文献   
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Although proactive followership behavior is often viewed as instrumental to group success, leaders do not always respond favorably to the actions of overly eager followers. Guided by a constructivist perspective, we investigated how interpretations of followership differ across the settings in which acts of leadership and followership emerge. In thematically analyzing data from semi‐structured interviews with leaders of high‐performing teams, we depict how the construal of follower behaviors relates to various contextual factors underscoring leader–follower interactions. Prototypical characteristics were described in relation to ideal followership (i.e., active independent thought, ability to process self‐related information accurately, collective orientation, and relational transparency). However, proactive followership behaviors were subject to the situational and relational demands that were salient during leader–follower interactions. Notably, the presence of third‐party observers, the demands of the task, stage in the decision‐making process, suitability of the targeted issue, and relational dynamics influenced which follower behaviors were viewed as appropriate from the leader's perspective. These findings provide insight into when leaders are more likely to endorse proactive followership, suggesting that proactive followership requires an awareness of how to calibrate one's actions in accordance with prevailing circumstances. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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Cost data were analyzed from thirty steam power plant units utilizing electrostatic precipitators with or without mechanical centrifugal collectors. Operational, maintenance, and total costs for the years 1969, 1970, and 1971 were expressed in 1972 dollars as $/cfm-yr and $/cfm-yr-efficiency. The latter parameter is a new one which normalizes the cost of air cleaning by accounting for the amount of particulate matter collected. Large differences in the costs of air cleaning were found between plants and even between units operating in the same plant. Maintenance costs appeared to be the main contributor to large total cost differences, but improved, more specific accounting procedures are required to focus more closely on the reasons for cost differences.  相似文献   
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