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161.
A survey of 1351 people who lived within 50 miles of one of six US Department of Energy nuclear weapon sites showed that the vast majority of residents prefer strong public health surveillance and land use controls. The sample was stratified so that the same number of responses was obtained at each site. The strongest correlates of wanting the DOE to restrict on-site activities and maintain and expand its surveillance programs were worries about DOE activities on the site, as well as how those activities could damage the off-site environment. Notably, the exceptions, that is, those who demanded less from the DOE and were not particularly worried about the DOE's activities, tended to live near the site, many worked there or knew people who did, and had high socio-economic status, and trusted the DOE. The findings are mostly, but not entirely, consistent with expectations drawn from the risk perception and organizational trust literatures. The challenge is how to establish a stewardship program that represents a consensus among state and local government, community advisory boards and the public that remediation can go on at the same time that some waste is managed on-site until suitable technologies can be safely deployed, which at some sites means 100 years or in perpetuity.  相似文献   
162.
Introduction. With the current increases in occupational skin diseases, literature data attesting the decreasing efficiency of barrier creams with respect to the manufacturer’s declarations and legal regulations granting skin protection gels for employees, research is required to analyse and evaluate the recipes used for hydrophilic skin protection gels based on polyacrylates. Methods. This study investigated the rheological properties, pH and sensory perception of hydrophilic barrier gels based on polyacrylates. Results. The acrylic acid derivatives used were good thickeners, and helped to form transparent gels of adequate durability. They could be used to create hydrophilic films on the surface of the skin to protect it against hydrophobic substances. A correlation was shown between the results of the rheological properties and the barrier properties of the gels. This confirms the possibility of monitoring the quality of the gels at the stage of recipe development. Conclusions. Polyacrylates are viable for use in industry to produce hydrophilic barrier creams suitable for skin protection.  相似文献   
163.
Purpose. With reference to four minimally invasive surgery (MIS) cholecystectomies, the aims were (a) to recognize the factors influencing dominant wrist postures manifested by the surgeon; (b) to detect risk factors involved in maintaining deviated wrist postures; (c) to compare the wrist postures of surgeons while using laparoscopic tools. Methods. Video films were recorded during live surgeries. The films were synchronized with wrist joint angles obtained from wireless electrogoniometers placed on the surgeon's hand. The analysis was conducted for five laparoscopic tools used during all surgical techniques. Results. The most common wrist posture was extension. In the case of one laparoscopic tool, the mean values defining extended wrist posture were distinct in all four surgical techniques. For one type of surgical technique, considered the most beneficial for patients, more extreme postures were noticed regarding all laparoscopic tools. We recognized a new factor, apart from the tool's handle design, that influences extreme and deviated wrist postures. It involves three areas of task specification including the type of action, type of motion patterns and motion dynamism. Conclusions. The outcomes proved that the surgical technique which is best for the patient imposes the greatest strain on the surgeon's wrist.?  相似文献   
164.
Levels of mercury and other contaminants should be lower in birds nesting on isolated oceanic islands and at high latitudes without any local or regional sources of contamination, compared to more urban and industrialized temperate regions. We examined concentrations of arsenic, cadmium, chromium, lead, manganese, mercury and selenium in the eggs, and the feathers of fledgling and adult glaucous-winged gulls (Larus glaucescens) nesting in breeding colonies on Adak, Amchitka, and Kiska Islands in the Aleutian Chain of Alaska in the Bering Sea/North Pacific. We tested the following null hypotheses: 1) There were no differences in metal levels among eggs and feathers of adult and fledgling glaucous-winged gulls, 2) There were no differences in metal levels among gulls nesting near the three underground nuclear test sites (Long Shot 1965, Milrow 1969, Cannikin 1971) on Amchitka, 3) There were no differences in metal levels among the three islands, and 4) There were no gender-related differences in metal levels. All four null hypotheses were rejected at the 0.05 level, although there were few differences among the three test sites on Amchitka. Eggs had the lowest levels of cadmium, lead, and mercury, and the feathers of adults had the lowest levels of selenium. Comparing only adults and fledglings, adults had higher levels of cadmium, chromium, lead and mercury, and fledglings had higher levels of arsenic, manganese and selenium. There were few consistent interisland differences, although levels were generally lower for eggs and feathers from gulls on Amchitka compared to the other islands. Arsenic was higher in both adult feathers and eggs from Amchitka compared to Adak, and chromium and lead were higher in adult feathers and eggs from Adak compared to Amchitka. Mercury and arsenic, and chromium and manganese levels were significantly correlated in the feathers of both adult and fledgling gulls. The feathers of males had significantly higher levels of chromium and manganese than did females. The levels of most metals in feathers are below those known to be associated with adverse effects in the gulls or their predators. However, levels of mercury in some gull eggs are within a range suggesting that several eggs should not be eaten in one day by sensitive humans.  相似文献   
165.
Many large neighbourhoods are located near heavy-traffic roads; therefore, it is necessary to control the levels of air pollution near road exposure. The primary air pollutants emitted by motor vehicles are CO, NO2 and PM. Various investigations identify key health outcomes to be consistently associated with NO2 and CO. The objective of this study was the measurement-based assessment for determining whether by high-traffic roads, such as motorways and express ways, and the concentrations of CO and NO2 are within normal limits and do not pose threat to the local population. Average daily values (arithmetic values calculated for 1-h values within 24 h or less, depending on result availability) were measured for concentrations of NO2 and CO by automatic stations belonging to the Voivodship Environmental Protection Inspectorate in Katowice, in areas with similar dominant source of pollutant emission. The measurements were made in three sites: near the motorway and expressway, where the average daily traffic intensity is 100983 and 35414 of vehicles relatively. No evidence was found of exceeding average daily values equal to the maximum allowable NO2 concentration due to the protection of human health in the measurement area of the stations. No daily average values exceeding the admissible CO concentration (8-h moving average) were noted in the examined period. The results clearly show lack of hazards for general population health in terms of increased concentrations of CO and NO2 compounds that are closely related to high intensity car traffic found on selected motorways and speedways located near the city centres.  相似文献   
166.
167.
Incubation temperature in ectothermic vertebrates affects incubation periods, and in some reptiles it affects sex ratios and behavior. I present evidence that incubation temperature affects emergence and post-hatching behavior of pine snakes (Pituophis melanoleucus) that could influence survival in the weeks before hibernation. Hatchlings incubated at low temperatures remained in the nest longer, had fewer alternate nest openings, and fewer underground tunnels to hide in than did hatchlings from warmer temperatures. These conditions could render hatchlings from low-temperature nests more vulnerable to predation because, if a nest is opened, they are not inside tunnels where they would be protected. Hatchlings from nests incubated at low temperatures took longer to find shade during a thermoregulation test, and were less likely to move about in search of other cover than were those from higher-incubation-temperature artificial nests. Similarly, hatchlings from nests with low incubation temperatures were less responsive to a predatory stimulus and had a longer latency to strike than other hatchlings. Taken together, hatchlings from nests with low incubation temperatures might be less able to avoid predators and find shade than those from nests incubated at higher temperatures, and thus could be expected to have lower survival in nature. Received: 21 July 1997 / Accepted after revision: 15 February 1998  相似文献   
168.
Non-optimal pH, dissolved oxygen concentration, the presence of toxic substances, or the influence of grazers are known to cause disturbances in nitrification. Because activated sludge is a mixture of different organisms, bacteria, and higher organisms, the stability of processes such as carbon removal, nitrification, denitrification, and dephosphatation depends on a range of interactions. These interactions occur both between and within trophic levels. Understanding of the ecology of microorganisms involved in bioprocesses is essential for effective control of startup and operation of a particular process. The aim of the study was to gain further insight into the dynamics of nitrifiers in activated sludge at various sludge ages while treating higher concentrations of ammonium. The results confirmed the importance of Nitrosococcus mobilis and Nitrobacter sp. as the dominant nitrifiers responsible for nitritation and nitratation, respectively, in the presence of unlimited ammonium. The size of the dominant bacteria colony was larger compared to the other species present and reached 25 microm. Problems with nitrification occurred in all high-ammonium loaded reactors. The dynamics of nitrifier population was monitored by oxygen uptake rate (OUR) using a test enabling the OUR measurement separately for ammonium-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB). The results reveal the hypersensitivity of nitrifiers to the substrate and products of incomplete nitrification.  相似文献   
169.
The green economy is an emergent approach to sustainable development launched at Rio+20. Herein environmental decision-making is increasingly achieved through economistic processes and logic. The natural commons are quantified and managed as natural capital. This paper summarizes the trajectory of the project and its ideological framework. It examines various conceptualizations of economic approaches to the environment and considers philosophical, methodological, and political problems associated with the green economy project. In the face of very different definitions of what constitutes a green economy, environmental communicators face a situation characterized by discursive confusion as the complexity of natural capital accounting processes conceal new political configurations. Counter movements argue that the green economy program is performing ideological work that uses language of environmentalism to obscure an intensified agenda of neoliberal governance and capital accumulation. The concept now has contradictory meanings. Environmental communicators have an important role to play in exposing the contested nature of the project and in helping to define the emerging green economy.  相似文献   
170.
Disturbances by insects have considerable effect on the heterogeneity of forested landscapes in North America. Responding to calls for bringing human dimensions of landscape disturbance and heterogeneity into ecological assessments and management strategies, this paper explores linkages between biophysical, socioeconomic, and perceptual aspects of a mountain pine beetle (MPB) (Dendroctonus ponderosae) outbreak in north central Colorado. Findings are presented from surveys conducted with residents of nine Colorado communities and variations in local perceptions of MPB risks and forest management attitudes are compared to indices of tree mortality and amenity characteristics. Findings suggest respondents from lower amenity communities with more recent emphasis on resource extraction and higher tree mortality had significantly higher risk perceptions of some MPB impacts, lower trust in federal forest management, and higher faith in forest industry and specific industry options than those from higher amenity communities with less tree mortality. While not implying these contextual influences fully explain such perceptual dimensions, this paper explores possible implications of heterogeneity across human landscapes for improving the saliency and efficiency of regional forest management and planning.  相似文献   
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