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91.
OBJECTIVE: To explore the epidemiology of pedestrian deaths in Dallas County, Texas, and to compare factors associated with pedestrian deaths on expressways versus those that occurred on other roadways. METHODS: We studied all pedestrian deaths among persons 15 years of age or older in Dallas County, Texas, from 1997 to 2004 by linking data from Medical Examiner's office, the Fatality Analysis Reporting System, and local police records. Univariate and multivariate analysis compared various factors associated with death on an expressway. RESULTS: Among 437 pedestrian deaths who were 15 years of age or older, 197 (45%) occurred on expressways; the proportion that occurred on expressways was highest among 15- to 29-year-olds (65%) and was lower with advancing age group (p < 0.01, chi square for trend). At least 36% of these expressway-related pedestrian deaths were known to have been "unintended pedestrians," who had exited a vehicle after being on the roadway, compared with 11% of pedestrian deaths on surface streets (OR 4.6, 95% CI, 2.7-8.1), and this was also highest among younger age groups. Pedestrian deaths on an expressway, compared with deaths on surface streets, remained strongly associated with having been an "unintended pedestrian" (OR 6.2, 95% CI, 3.1-14.0), after controlling for several other variables, including age, sex, race, nighttime of crash, and alcohol involvement. CONCLUSIONS: Expressways are the predominant site of fatal pedestrian crashes among young adults in this urban area. Since many of these deaths were "unintended pedestrians," procedures for management of occupants of disabled vehicles on expressways could have a large impact on pedestrian deaths in young adults.  相似文献   
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Nitrous oxide (N2O) is a major greenhouse gas (GHG) product of intensive agriculture. Fertilizer nitrogen (N) rate is the best single predictor of N2O emissions in row-crop agriculture in the US Midwest. We use this relationship to propose a transparent, scientifically robust protocol that can be utilized by developers of agricultural offset projects for generating fungible GHG emission reduction credits for the emerging US carbon cap and trade market. By coupling predicted N2O flux with the recently developed maximum return to N (MRTN) approach for determining economically profitable N input rates for optimized crop yield, we provide the basis for incentivizing N2O reductions without affecting yields. The protocol, if widely adopted, could reduce N2O from fertilized row-crop agriculture by more than 50%. Although other management and environmental factors can influence N2O emissions, fertilizer N rate can be viewed as a single unambiguous proxy—a transparent, tangible, and readily manageable commodity. Our protocol addresses baseline establishment, additionality, permanence, variability, and leakage, and provides for producers and other stakeholders the economic and environmental incentives necessary for adoption of agricultural N2O reduction offset projects.  相似文献   
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Studies have shown that ecological restoration projects are more likely to gain public support if they simultaneously increase important human services that natural resources provide to people. River restoration projects have the potential to influence many of the societal functions (e.g., flood control, water quality) that rivers provide, yet most projects fail to consider this in a comprehensive manner. Most river restoration projects also fail to take into account opportunities for revitalization of large-scale river processes, focusing instead on opportunities presented at individual parcels. In an effort to avoid these pitfalls while planning restoration of the Sacramento River, we conducted a set of coordinated studies to evaluate societal impacts of alternative restoration actions over a large geographic area. Our studies were designed to identify restoration actions that offer benefits to both society and the ecosystem and to meet the information needs of agency planning teams focusing on the area. We worked with local partners and public stakeholders to design and implement studies that assessed the effects of alternative restoration actions on flooding and erosion patterns, socioeconomics, cultural resources, and public access and recreation. We found that by explicitly and scientifically melding societal and ecosystem perspectives, it was possible to identify restoration actions that simultaneously improve both ecosystem health and the services (e.g., flood protection and recreation) that the Sacramento River and its floodplain provide to people. Further, we found that by directly engaging with local stakeholders to formulate, implement, and interpret the studies, we were able to develop a high level of trust that ultimately translated into widespread support for the project.  相似文献   
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The availability of heavy metals in contaminated sediment evaluated for beneficial reuse, before and after chemical amendment, was evaluated using poultry manure as the amendment. The dredged sediment was only slightly contaminated with heavy metals. Availability tests on the amended sediment showed an increase in heavy metals, most likely because of poultry feed amendments passed to the manure. There would be difficulty finding one chemical amendment to reduce the availability of a number of heavy metals because the metals exhibit different chemical properties. © 2001 John Wiley & Sons, Inc.  相似文献   
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In the last decade policy makers have increasingly recognized the need to include people's perceptions in methods for describing landscape quality. At the same time, a third wave of Geographic Information Systems (GIS) has become available that make it technically possible to model landscape quality in a realistic manner. However, as there is often a mismatch between science and policy, it remains unclear to what extent perception-based models developed by scientists can be useful to policy makers. The aim of the present study was to evaluate the usefulness to policy making of a GIS-based procedure for describing perceived landscape openness. To this end, a workshop was organized which was attended by eight Dutch policy makers who acted as representatives of their province (region). The Group Decision Room (GDR) technique was used to elicit the policy makers' evaluations of the procedure in an anonymous and reliable manner. The procedure was presented to the policy makers using cases from their own province, which they assessed using a mixture of qualitative and quantitative methods. The results show that policy makers rated the procedure as being highly relevant to policy making, scientifically credible, usable by policy makers and feasible to implement in the policy making process. They especially appreciated the flexibility and transparency of the procedure. The policy makers concluded that the procedure would be of most value for monitoring landscape changes and for analysing impacts on landscape openness in land use scenario studies. However, they requested guidelines for proper implementation of the various options in the procedure. In general, the current study shows that explicit and transparent evaluation of the usefulness of GIS-based tools can aid integration at the science-policy interface and help to ensure that both scientists and policy makers are informed of interrelated options and requirements.  相似文献   
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Campylobacter is a gram-negative, microaerophilic, curved rod and a normal resident of the gastrointestinal flora and may be the cause of disease in animals. Transmission to humans occurs by ingestion of contaminated food or by direct contact with infected animals. In the past few decades, an increasing number of reports have implicated the presence of this organism in human abortions as well. An infectious mechanism due to primary placental inflammatory damage followed by secondary damage to the fetus following placental insufficiency and ischemia was suggested. The most common species of Campylobacter are Campylobacter jejuni and Campylobacter coli, which are classically associated with enteritis in humans. We present a rare case of mid-gestation intrauterine growth restriction (IUGR) associated with maternal bacteremia caused by C. coli infection. Our literature review focuses on Campylobacter infections occurring in the second and third trimesters of pregnancy. In all cases, mild maternal symptoms consisting of fever and weakness were presented. However, associated adverse fetal outcome, including abortions, IUGR or preterm labor may occur more frequently than anticipated. Our report strengthens the importance of awareness to this finding and focuses the need to consume properly cooked meat during pregnancy. © 2015 John Wiley & Sons, Ltd.  相似文献   
100.
精神分析批评作为一种文学批评方法,可以用于解释作者的创作动机和研究文学文本。简要梳理精神分析批评的理论渊源,分析其对文学研究的影响,指出其缺陷,旨在帮助文艺批评者更好、更有效地运用于文学批评。  相似文献   
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