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151.
Climate change caused by increased anthropogenic emissions of carbon dioxide (CO2) and other greenhouse gases is a long-term climate hazard with the potential to alter the intensity, temporal pattern, and spatial extent of the urban heat island (UHI) in metropolitan regions. Particular meteorological conditions—including high temperature, low cloud cover, and low average wind speed—tend to intensify the heat island effect. Analyses of existing archived climate data for the vicinities of Newark and Camden, New Jersey indicate urban to suburban/rural temperature differences over the previous half-century. Surface temperatures derived from a Landsat thermal image for each site were also analyzed for spatial patterns of heat islands. Potential interactions between the UHI effect and projected changes in temperature, wind speed, and cloud cover are then examined under a range of climate change scenarios, encompassing different greenhouse gas emissions trajectories. The scenarios include those utilized in the Metropolitan East Coast Regional Assessment of Climate Variability and Change and the A2 and B2 scenarios of the Intergovernmental Panel on Climate Change (IPCC) Special Report on Emissions Scenarios (SRES).

The UHI effect was detected in Newark and Camden in both satellite surface-temperature and meteorological station airtemperature records. The average difference in urban—nonurban minimum temperatures was 3.0 °C for the Newark area and 1.5 °C for Camden. Extrapolation of current trends and the selected global climate models (GCMs) project that temperatures in the case study areas will continue to warm in the current century, as they have over the past half-century. An initial analysis of global climate scenarios shows that wind speed may decline, and that cloud cover may increase in the coming decades. These generally small countervailing tendencies suggest that urban—nonurban temperature differences may be maintained under climate change.

Overall warmer conditions throughout the year may extend the spatial and temporal dimensions of the urban-suburban heat complex. The incidence of heat-related morbidity and mortality are likely to increase with interactions between the increased frequency and duration of heat waves and the UHI effect. Camden and Newark will likely be subjected to higher temperatures, and areas experiencing UHI-like conditions and temperature extremes will expand. Thus, urban heat island-related hazard potential is likely to increase in a warmer climate.  相似文献   
152.
This study begins by examining the dimensionality of the Type A behavior pattern using four frequently employed self-report measures. Exploratory and confirmatory factor analyses identified nine meaningful factors (dimensions) across the four scales. A measure of hostility was added since hostility has been found to be highly predictive of coronary heart disease and originally was included in Rosenman, Swan and Carmelli's (1988) definition of Type A behavior. Supporting the utility of examining Type A behavior as a multidimensional personality construct, the Type A dimensions and hostility reveal differential effects on academic performance and a general health or psychiatric disorder symptom profile. Achievement striving is positively related to academic performance, and time pressure, anger, and hostility seem to significantly increase somatic complaints, anxiety, and depression. In addition, there is support for Price's (1982) conceptualization that some cognitive beliefs and fears promote the development and maintenance of Type A behavior. As expected, the belief and fear that one must prove oneself or else be judged unworthy relates positively to work involvement and achievement striving, but it also directly and positively impacts the overt Type A behaviors of hurry and time pressure and two psychiatric health disorder symptoms, performance dysfunction and anxiety. Lastly, implications and future research directions are discussed.  相似文献   
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154.
Current methods for tracking pathogens across farmland and into surrounding waterways via runoff are limited and typically have been developed using artificially created landscapes. No studies have investigated how Giardia in farm runoff moves across the landscape, despite high prevalence rates in dairy cattle (Bos taurus) worldwide. Here, we report the development of a field-based tracking method specific for Giardia movement in runoff and use this technique to compare the pathogen reduction capability of recently planted vegetation strips with bare soil strips cleared of vegetation. Such scenarios represent typical events in schemes to plant vegetation barriers aimed at reducing waterway contamination. A significant treatment effect was identified, with 26% fewer Giardia detected in runoff collected from the planted strip (P = 0.006). These results highlight the immediate benefit of pathogen removal to be gained from vegetation planting. The successful discrimination of treatment effects by this new technique will enable the assessment of different vegetation types on runoff reduction and the effects of plant development over time.  相似文献   
155.
Laboratory experiments have been performed to investigate the effects of salt exclusion on the behaviour of lakes with salinities up to 8 g L?1. At these salinities the freezing temperature is less than the temperature of maximum density and, unlike sea-ice, a reverse temperature stratification forms beneath the ice that can support at least some of the excluded salt. Temperature time series at four depths showed that salt exclusion drives cascades of localised overturning, while the persistence of reverse temperature stratification indicated that mixing was not complete. While our array of temperature sensors had insufficient spatial resolution to provide full details of the flow, we hypothesize that: at salinities of 1 and 2 g L?1  salt is released relatively uniformly and forms a layer of elevated salinity immediately below the ice, which supports double-diffusive salt-fingering; and at salinities of 4 and 8 g L?1, salt plumes penetrate the reverse stratification. After the ice melted, a relatively fresh surface layer formed above a more saline layer, sufficient to suppress spring turnover. Our measurements compare favourably with field observations from lakes, and highlight the importance of salt exclusion on biogeochemical processes in lakes.  相似文献   
156.
The demand for gender analysis is now increasingly orthodox in natural resource programming, including that for small-scale fisheries. Whilst the analysis of social–ecological resilience has made valuable contributions to integrating social dimensions into research and policy-making on natural resource management, it has so far demonstrated limited success in effectively integrating considerations of gender equity. This paper reviews the challenges in, and opportunities for, bringing a gender analysis together with social–ecological resilience analysis in the context of small-scale fisheries research in developing countries. We conclude that rather than searching for a single unifying framework for gender and resilience analysis, it will be more effective to pursue a plural solution in which closer engagement is fostered between analysis of gender and social-ecological resilience whilst preserving the strengths of each approach. This approach can make an important contribution to developing a better evidence base for small-scale fisheries management and policy.  相似文献   
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158.
Sustainable engineering is a conceptual and practical challenge to all engineering disciplines. Although the profession has experience with environmental dimensions of engineering activities that in some cases are quite deep, extending the existing body of practice to sustainable engineering by including social and cultural domains is a significant and non-trivial challenge. Nonetheless, progress is being made, as a recent study undertaken by the Center for Sustainable Engineering in the United States demonstrates.
Brad AllenbyEmail:
  相似文献   
159.
Automotive catalyst deactivation can be promoted by thermal and poisoning mechanisms. Catalyst efficiency is reduced by thermal degradation resulting in the agglomeration of precious metals and the reduction of the washcoat surface area. In this paper, the temperature influence on the commercial Pd/Rh-based automotive catalyst performance was studied. Textural and physicochemical characterisation techniques were employed, such as X-ray fluorescence (XRF), atomic absorption spectrometry (AAS), N2 physisorption, X-ray diffraction (XRD), temperature programmed reduction (TPR) and scanning electron microscopy coupled with energy-dispersive X-ray analysis (SEM–EDX). The catalysts were evaluated for CO and propane oxidation with a stoichiometric gas mixture similar to engine exhaust gas. The results indicated the transformation of alumina into high temperature phases and the formation of new mixed oxide phases. Evidence of sintered particles and several spots of palladium agglomerates was seen by SEM–EDX analysis. The activity results showed the effects of thermal deactivation on the conversion of the pollutants. In spite of exposure to extreme temperature conditions (72 h at 1200 °C), significant activity was still observed for carbon monoxide and propane oxidation reactions.  相似文献   
160.
Because management is driven largely by financial concerns, determining the cost of environmental quality is a critical step in developing an environmental TQM program for which management will actively demonstrate commitment and support. Costs of environmental quality can be grouped into three categories: failure, prevention, and appraisal. The total cost of environmental quality can be used as a benchmark to monitor the level of environmental quality and to justify the redirection of resources.  相似文献   
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