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121.
The tsunami that struck South-east Asia on 26 December 2004 left more than 500,000 people in Aceh, Indonesia, homeless and displaced to temporary barracks and other communities. This study examines the associations between prolonged habitation in barracks and the nature of fears reported by school-age children and adolescents. In mid-2007, 30 months after the tsunami, the authors interviewed 155 child and parent dyads. Logistic regression analysis was used to compare the fears reported by children and adolescents living in barracks with those reported by their peers who were living in villages. After adjusting for demographic factors and tsunami exposure, the data reveals that children and adolescents living in barracks were three times more likely than those living in villages to report tsunami-related fears. The study demonstrates that continued residence in barracks 30 months after the tsunami is associated with higher rates of reporting tsunami-related fears, suggesting that barracks habitation has had a significant impact on the psychological experience of children and adolescents since the tsunami.  相似文献   
122.
The observed composition of visibility-reducing aerosols in the Grand Canyon region is summarized in climatological terms. Observations are from SCENES, a measurement program extending from 1984 to 1989. Results are presented as average mass balances stratified by various factors.Aerosols were found to exhibit substantial seasonal variation, but little systematic diurnal variation. Crustal material was a dynamic component, and peaked during springtime. Aerosol composition, but not total concentration, depended strongly on ambient relative humidity, with crustal material augmented at low humidities and sulfates augmented at high humidities. Total fine-particle concentrations correlated strongly with light scattering, as expected; however, little association between chemical composition and light scattering was observed.  相似文献   
123.
Causal relationships involving role stressors, physical symptomatology, and turnover intentions were examined within three alternative specifications. These specifications stemmed from Beehr and Newman's (1978) and Schuler's (1982) models of role stress and Locke's (1976) theory of job satisfaction. The results, derived from LISREL VI analyses, indicate that a revised Schuler model is the most plausible specification. Findings are discussed in terms of implications for understanding role stress and employee withdrawal.  相似文献   
124.
The primary goal of this study was to characterize physical habitat and benthic communities (macroinvertebrates) in the Stanislaus, Tuolumne and Merced Rivers in California’s San Joaquin Valley in 2003. These rivers have been listed as impaired water bodies (303 (d) list) by the State of California due to the presence of organophosphate (OP) insecticides chlorpyrifos and diazinon, Group A pesticides (i.e., organochlorine pesticides), mercury, or unknown toxicity. Based on 10 instream and riparian physical habitat metrics, total physical habitat scores in the Stanislaus River ranged from 124 to 188 (maximum possible total score is 200). The highest total habitat score was reported at the upstream site. Tuolumne River physical habitat scores ranged from 86 to 167. Various Tuolumne River physical habitat metrics, including total habitat score, increased from downstream to upstream in this river. Merced River physical habitat scores ranged from 121 to 170 with a significant increase in various physical habitat metrics, including total habitat score, reported from downstream to upstream. Channel flow (an instream metric) and bank stability (a riparian metric) were the most important physical habitat metrics influencing the various benthic metrics for all three rivers. Abundance measures of benthic macroinvertebrates (5,100 to 5,400 individuals) were similar among the three rivers in the San Joaquin watershed. Benthic communities in all three rivers were generally dominated by: (1) Baetidae species (mayflies) which are a component of EPT taxa generally considered sensitive to environmental degradation; (2) Chironomidae (midges) which can be either tolerant or sensitive to environmental stressors depending on the species; (3) Ephemerellidae (mayflies) which are considered sensitive to pollution stress; and (4) Naididae (aquatic worms) which are generally considered tolerant to environmental stressors. The presence of 117 taxa in the Stanislaus River, 114 taxa in the Tuolumne River and 96 taxa in the Merced River implies that the benthic communities in these streams are fairly diverse but without a clear definition of benthic community expectations it is unknown if these water bodies are actually impaired.  相似文献   
125.
The reduction of SO2, HCl, and NO(x) concentrations using calcium magnesium acetate (CMA) as a novel sorbent in a simulated municipal waste incinerator flue gas was investigated. The reduction of individual SO2, HCl, and NO(x) concentrations was tested at 850 degrees C and it was found that CMA could reduce the SO2 concentration by 74%, HCl concentration by 64%, or NO(x) concentration by 94%. It was observed that individual SO2 or HCl capture increased with increasing initial oxygen concentration in the reacting gas or increasing sorbent input. NO(x) reduction decreased with increasing initial oxygen concentration in the reacting gas. The simultaneous reduction of SO2, HCl, and NO(x) concentrations by CMA was also investigated. It was found that CMA could simultaneously capture 60% SO2 and 61% HCl and reduce NO(x) concentrations by 26%, when the initial oxygen concentration in the reacting gas was 4%. During the simultaneous reduction of SO2, HCl, and NO(x), it was noted that as the initial oxygen concentration in the reacting gas increased, the efficiency of SO2 capture increased too, but the efficiency of HCl capture and the efficiency of NO(x) destruction decreased.  相似文献   
126.
Much effort has been directed toward elucidating pollution effects on marine benthic communities (Pearson and Rosenberg, 1978; Sanders et al., 1980; NAS 1985). Less effort has been directed at methods of data analysis which will identify distribution patterns and relationships between communities. Traditional community structure summary parameters such as species richness and various indices of diversity utilize only part of the information contained in a data set and are not very useful in elucidating relationships between communities of animals.  相似文献   
127.
128.
The potential of powerline rights-of-way to provide songbird habitat in an urbanizing environment was assessed over a 7-month.period. Comparisons of species richness and total number of birds observed were made with a nearby residential development. The right-of-way, for 7 years free from herbicide manipulation, exhibited a greater number of species (but fewer individuals) and higher bird species diversity (BSD) than the residential area. The importance of mixed-shrub communities for the provision of niches for songbirds was demonstrated by increased BSD in residential vacant lots and sections of the right-of-way containing a variety of vegetative profiles. Recommendations are presented on right-of-way vegetation management to enhance songbird utilization.  相似文献   
129.
130.
This paper describes a linear program-based computer model which has been developed to identify the most effective spending patterns for environmental cleanup based on public preferences and spending limitations. The inputs to the model include the costs of removing each residual studied from its various sources. The objective function is the total “value of removal”. The factor added for each residual consists of a value for the residual multiplied by the quantity or fraction removed.Results of the analysis relate to and support current and projected policy decisions by the U.S. Environmental Protection Agency (EPA) for air and water programs. In addition, the results of the analysis suggest that EPA undertake a redirection of the Nation's resources among residual control programs.  相似文献   
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