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91.
Determining sources of neurotoxic metals in rural and urban soils is important for mitigating human exposure. Surface soil from four areas with significant clusters of mental retardation and developmental delay (MR/DD) in children, and one control site were analyzed for nine metals and characterized by soil type, climate, ecological region, land use and industrial facilities using readily available GIS-based data. Kriging, principal component analysis (PCA) and cluster analysis (CA) were used to identify commonalities of metal distribution. Three MR/DD areas (one rural and two urban) had similar soil types and significantly higher soil metal concentrations. PCA and CA results suggested that Ba, Be and Mn were consistently from natural sources; Pb and Hg from anthropogenic sources; and As, Cr, Cu, and Ni from both sources. Arsenic had low commonality estimates, was highly associated with a third PCA factor, and had a complex distribution, complicating mitigation strategies to minimize concentrations and exposures.  相似文献   
92.
Ian Davis 《Disasters》2019,43(Z1):S61-S82
This reflection, based on a keynote address to celebrate the fortieth anniversary of Disasters on 14 September 2017, begins by considering some of the prevailing assumptions that existed at the time of the journal's creation. Next is a summary of significant milestones during the past 40 years, covering major global trends, changing disaster impacts, and key developments in disaster risk management. Contrasting approaches in the first and fourth decade of the journal's history are then followed by examples of changes in terminology in the disaster field as an indication of shifting values. The paper goes on to explore the context of 2017, with observations of problem areas such as the loss of knowledge, failures to tackle the root causes of disasters, shortfalls in international assistance, and some negative attitudes. It closes by evaluating some current positive occurrences, including a reduction in casualties, sharing of experience, technological advances, and dramatic improvements in disaster warning.  相似文献   
93.
Abstract

The impact of weather on air pollution was examined and evaluated for the city of Athens, Greece. We used an objectively defined synoptic classification scheme consisting of six summer and eight winter circulation types. This scheme was established using a combination of both factor and cluster analysis during 1954–1999. Surface and isobaric levels of 850 hPa data were used. Factor analysis combined with cluster analysis was used to derive circulation types based on surface meteorological data for the period 1954–1999 in Athens and on surface pressure grid data. The city was divided into three sectors according to the financial and social activities of the residents. To examine the spatial characteristics of pollutant concentrations over Athens for each synoptic type, the synoptic circulation types were then correlated with both gaseous and particulate pollutant concentrations measured in each sector between 1983 and 1999. Finally, extreme and severe episodic events were studied in terms of their meteorological and synoptic characteristics.  相似文献   
94.
95.
Urban stream restoration continues to be used as an ecological management tool, despite uncertainty about the long‐term sustainability and resilience of restored systems. Evaluations of restoration success often focus on specific instream indicators, with limited attention to the wider basin or parallel hydrologic and geomorphic process. A comprehensive understanding of urban stream restoration progress is particularly important for comparisons with nonurban sites as urban streams can provide substantial secondary benefits to urban residents. Here, we utilize a wide range of indicators to retrospectively examine the restoration of Nine Mile Run, a multi‐million dollar stream restoration project in eastern Pittsburgh (Pennsylvania, USA). Examination of available continuous hydrological data illustrates the high cost of failures to incorporate the data into planning and adaptive management. For example, persistent extreme flows drive geomorphic degradation threatening to reverse hydrologic connections created by the restoration and impact the improved instream biotic communities. In addition, human activities associated with restoration efforts suggest a positive feedback as the stream restoration has focused effort on the basin beyond the reach. Ultimately, urban stream restoration remains a potentially useful management tool, but continued improvements in post‐project assessment should include examination of a wider range of indicators.  相似文献   
96.
Amino acids, proteins, and peptides are found ubiquitously in waters. They can form harmful byproducts during water treatment by reaction with disinfectants. Chlorination and chloramination of water containing natural organic matter is known to result in the production of toxic substances, often referred to as disinfection byproducts. The main advantage of using chlorine dioxide (ClO2) over other known chlorine-containing disinfectants is the minimization of the formation of harmful trihalomethanes. Because ClO2 is a promising alternative to other chlorine-containing disinfectants, the chemistry of ClO2 interactions with amino acids, proteins, and peptides should be understood to ensure the safety of potable water supplies. Here, we present an overview of the aqueous chemistry of ClO2 and its reactivity with amino acids, peptides, and proteins. The kinetics and products of the reactions are reviewed. Only a few amino acids have been reported to be reactive with ClO2, and they have been found to follow second-order kinetics for the overall reaction. The rate constants vary from 10?2 to 107?M?1?s?1 and follow an order of reactivity: cysteine?>?tyrosine?>?tryptophan?>?histidine?>?proline. For reactions of histidine, tryptophan, and tyrosine with ClO2, products vary depending largely on the molar ratios of ClO2 with the specific amino acid. Products of ClO2 oxidation differ with the presence or absence of oxygen in the reaction mixture. Excess molar amounts of ClO2 relative to amino acids are associated with the production of low molecular weight compounds. The oxidation of the biochemically important compounds bovine serum albumin and glucose-6-phosphate dehydrogenase by ClO2 suggests a denaturing of proteins by ClO2 by an attack on tryptophan and tyrosine residues and relates to the inactivation of microbes by ClO2.  相似文献   
97.
The multi-disciplinary evaluation of a national agri-environment scheme   总被引:8,自引:0,他引:8  
With an increasing amount of public funds being spent on agri-environmental schemes effective methods have to be developed to evaluate them. As many schemes have multiple objectives there is a need for a multi-disciplinary approach to any evaluation. A method was developed to assess the degree to which ecological, landscape, historical and access objectives for the Countryside Stewardship Scheme (CSS) in England have been met. The method used a sample of 484 agreements for which data were collected from surveys, a desk study and an interview with the agreement holder. These data were then evaluated by an expert team of an ecologist, landscape architect, landscape historian, and a social scientist specializing in rural affairs. The team were subsequently brought together with a Chair to discuss their findings for each agreement, allocating scores for each of five criteria: agreement negotiation; appropriateness, environmental effectiveness, compliance and side effects. The additionality that each agreement was likely to provide was also assessed. The results of this process suggest that in the majority of cases the CSS agreements should maintain or enhance the environment in terms of ecology, landscape, and landscape history and increase public enjoyment of the countryside. Thirty-six percent of agreements showed high additionality and 38% medium additionality which demonstrates that the CSS is likely to provide a benefit to society. Agreement negotiation, predicted environmental effectiveness and predicted compliance all improved significantly over the period 1996-98. Recommendations made from this project have been implemented by the Government department to improve the CSS. The multi-disciplinary method was successful and, with further development, could be used for assessment of any agri-environment scheme, or potentially any conservation project or broader 'rural development' scheme encompassing environmental, economic and social objectives. A key to success is the need for the criteria to be tailored for the project concerned and clearly established at the beginning.  相似文献   
98.
This research tested a multilevel model examining the influence of work‐family culture and supportive workplace relationships on work interference with family. Web‐based survey data were provided by 792 information technology employees from 10 organizations. Random coefficient modeling was used to test a path model examining the relationships between work‐family culture, leader‐member exchange (LMX), coworker support, and work interference with family. The direct effects of LMX and coworker support on work interference with family were significant. The indirect effect of work‐family culture on work interference with family was also significant. Results demonstrate the value of work‐family culture in understanding supportive supervisory and coworker relationships and work interference with family and highlight the need to employ multilevel models to understand these relationships. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
99.
Environmental planning legislation in New South Wales now requires local government authorities to draw up statutory plans that take into account, among other concerns, both the biophysical and the social environmental issues within their jurisdictions. The SIRO-PLAN method of plan production provides a systematic mechanism for fulfilling this requirement. This article describes the application of the method by planning researchers over 18 months to the production of a Local Environmental Plan for a rural local government in New South Wales. The policy formulation, the purposive data collection, and the deliberate adjustment of plans in order to recognize interest group requirements were all found to be valuable features of the method, while the translation of the ultimately chosen land-use plan into the explicit regulatory controls available to the local government authority was found to require further refinement. The capacity of SIRO-PLAN to quantify the resolution of competing environmental concerns in the final plan, although of value to planning researchers, proved too arcane for traditionally trained planners.  相似文献   
100.
Benthic macroinvertebrate communities in streams adjacent to cornfields, streams where cows had unrestricted access, and reference locations without agriculture were compared to examine the effects of local land use and land use/land cover in the watershed. At each local site, macroinvertebrates and a variety of habitat parameters were measured upstream, adjacent, downstream, and farther downstream of the local land use. A geographic information system (GIS) was used to calculate drainage basin area, land use/land cover percentages in each basin, and the distance from sample sites to the stream source. Three‐way analysis of covariance (ANCOVA) tests with date, site type, and sampling location as main effects were used to explore differences in macroinvertebrate metrics using median substrate size, percent hay/pasture area, and stream depth as covariates. The covariates significantly improved model fit and showed that multiple contributing factors influence community composition. Local impacts were greatest at sites where cows had access, probably because of sedimentation and embeddedness in the substrate. Differences between the upstream and the adjacent and downstream locations were not as great as expected, perhaps because upstream recolonization was reduced by agricultural impacts or because of differences in the intensity or proximity of agriculture to riparian areas in the watershed. The results underscore the importance of both local and watershed factors in controlling stream community composition.  相似文献   
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