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21.
This study tested Pleck's (1977) hypothesis concerning gender differences in the relative permeability of work and family boundaries. Data were obtained from a randomly drawn community sample of 631 employed adults (278 men; 353 women). Respondents reported that work interfered with family life (W→F conflict) more frequently than family life interfered with work (F→W conflict). These results suggest that work and family boundaries are indeed asymmetrically permeable with family boundaries being more permeable than work boundaries. However, there was no evidence of gender differences in the pattern of asymmetry, indicating that the dynamics of work and family boundaries may operate similarly among men and women. Implications for future research are discussed.  相似文献   
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Environmental Science and Pollution Research - Manganese (Mn) is an essential element that, in excess, seems to be involved in the development of different neurodegenerative conditions....  相似文献   
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In seed beetles, oviposition decisions may influence the offspring phenotype because eggs constitute the initial resources available for larval development. We tested the effects of host quality variations (small vs. large seeds of the host plant Calystegia sepium, Convolvulaceae) on oviposition patterns and offspring performance of the seed beetle Megacerus eulophus. We also manipulated the maternal diet: high diet quality vs. low diet quality to evaluate possible interactive effects of the maternal nutritional environment and host quality on oviposition patterns. We further assessed the consequences of egg size variation in offspring size. Female M. eulophus fed with high-quality diet (H-diet) laid more eggs and lived longer than females fed with low-quality diet (P-diet). Fecundity decreased under a low-quality host for both maternal diets. The occurrence of maternal environmental effects on egg size plasticity was detected. Under conditions of low-quality host, mothers fed with the high-quality diet produced bigger eggs in comparison with a high-quality host, whereas females fed with the low-quality diet produced smaller ones. Regardless of these differences observed in egg size depending on the maternal diet, progeny emerging from small seeds (low-quality host) showed a similar performance at emergence. Offspring traits were only significantly affected by host quality. Beetles emerging from large seeds had greater body weight and length than those reared on small seeds. Variations in oviposition patterns in response to host quality are discussed.  相似文献   
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Environmental and safety aspects of seasonal storage of baled municipal solid waste to be used as fuel for energy production (waste fuel), was investigated and experiments were carried out on burning of bales. The flammability, combustion processes and emissions were studied by simulating, in small-scale, potential effects of a possible fire in full-scale bale storage area. Despite the high water content and the high density of the bales, after setting fire, the bales burned well, even though no risk for self-ignition exists. The following parameters of the combustion product were measured continuously: O2, CO2, CO, SO2, NO, NO2, NOx, THC, smoke gas rate and the temperature of the smoke. Soot particles in the smoke were collected and analysed for Hg, Pb, Cd, As, Ni, Cr, Mn, Cu, Co, Sb and V concentrations. The analysis of the moisture content, concentrations of Hg, Cd, HCl, HF, HBr, NH3, polyaromatic hydrocarbons (PAH), chlorinated and brominated dioxins (PCDD/F and PBrDD/F, respectively) were carried out. It was found that the PCDD/F levels (TEQs) varied according to the system used: 12.53 ng (I-TEF-88)/Nm3; 14.09 ng (I-TEF-99)/Nm3; 13.86 ng (Eadons)/Nm3. The PAH concentration was 3.04 microg/Nm3. The contents of the metals in the smoke (with the exceptions of Pb and Cd with mean values of 1.74 and 0.36 mg/m3, respectively) were below the limit values established by the Swedish Ministry of Environment for emissions from incineration plants [Swedish Ministry of Environment, (2002:1060), F?rordning 2002:1060 om avfallsf?rbr?nning. Available from http://www.notisum.se/rnp/SLS/LAG/20021060.HTM]/EU-directive [(2000/76/EC), Directive 2000/76/EC, of the European Parliament and of the Council of 4 December 2000 on the Incineration of Waste. http://www.Scotland. gov.uk/library5/environment/iecda.pdf]. The HCl concentration was 10 times higher than the limit value (mean value of 99 mg/m3).  相似文献   
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Physico-chemical characteristics of waste, particularly fine fraction (FF), from an old crystal glass waste dump in Sweden were studied to assess recycling or disposal alternatives. Hand-sorting of the waste indicated glass content of 44.1% while sieving established the FF as a more soil-like mix of glass and other materials constituting 33.3% of all excavated waste. The FF was around neutral pH with 24.4% moisture content, low values of Total Dissolved Solids, Dissolved Organic Carbon and fluorides, but hazardous concentrations of As, Cd, Pb and Zn according to the Swedish Environmental Protection Agency guidelines. While the FF leached metals in low concentrations at neutral pH, it leached considerably during digestion with nitric acid, implying leaching risks at low pH. Thus, the waste requires safe storage in hazardous waste class ‘bank account’ storage cells to avoid environmental contamination as metal recovery and other recycling strategies for the glass waste are being developed. The study could fill the information gap regarding preservation of potential resources in the on-going, fast-paced excavation and re-landfilling of heavy metal contaminated materials in the region.  相似文献   
28.
Fish migrate to spawn, feed, seek refuge from predators, and escape harmful environmental conditions. The success of upstream migration is limited by the presence of barriers that can impede the passage of fish. We used a spatially explicit modeling strategy to examine the effects of barriers on passage for 21 native and non-native migratory fish species and the amount of suitable habitat blocked for each species. Spatially derived physical parameter estimates and literature based fish capabilities and tolerances were used to predict fish passage success and habitat suitability. Both the fish passage and the habitat suitability models accurately predicted fish presence above barriers for most common, non-stocked species. The fish passage model predicted that barriers greater than or equal to 6 m block all migratory species. Chinook salmon (Oncorhynchus tshawytscha) was expected to be blocked the least. The habitat suitability model predicted that low gradient streams with intact habitat quality were likely to support the highest number of fish species. The fish passage and habitat suitability models were intended to be used by environmental managers as strategy development tools to prioritize candidate dams for field assessment and make decisions regarding the management of migratory fish populations.  相似文献   
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Finding solutions for complex environmental, economic and social issues in organisations relies on coordinated actions among several social actors that are involved in the sustainable development web and demands that they learn new business methods. In this scenario, which involves multiple social actors, relationships, contexts and interests, social learning has emerged as a hybrid approach to resolving complex environmental and social problems. Such an approach marks a different situation for organisations whose focus is not only on supporting such problem resolution but also on transforming such crises into opportunities to generate sustainable products and services. Thus, this study discusses how one of the largest companies in Latin America’s chemical segment formed a network with 23 social actors and is socially learning to deal with the dialectic between return on investments for its shareholders and benefits for its stakeholders. Research was conducted based on Boje’s narrative analysis. The data was built through interviews, informal conversations, textual and audio-visual documents and non-participant observation. This paper discusses the concept and describes the social learning process for sustainability (in this case, for sustainable agriculture) from the viewpoint of a for-profit organisation. In this manner, this study contributes to strengthening the connection between social learning and sustainability.  相似文献   
30.
Non-point-source (NPS) pollution remains the primary source of stream impairment in the United States. Many problems such as eutrophication, sedimentation, and hypoxia are linked with NPS pollution which reduces the water quality for aquatic and terrestrial organisms. Increasingly, NPS pollution models have been used for landscape-scale pollution assessment and conservation strategy development. Our modeling approach functions at a scale between simple landscape-level assessments and complex, data-intensive modeling by providing a rapid, landscape-scale geographic information system (GIS) model with minimal data requirements and widespread applicability. Our model relies on curve numbers, literature-derived pollution concentrations, and land status to evaluate total phosphorus (TP), total nitrogen (TN), and suspended solids (SS) at the reach scale. Model testing in the Chesapeake Bay watershed indicated that predicted distributions of water quality classes were realistic at the reach scale, but precise estimates of pollution concentrations at the local scale can have errors. Application of our model in the tributary watersheds along Lake Ontario suggested that it is useful to managers in watershed planning by rapidly providing important information about NPS pollution conditions in areas where large data gaps exist, comparisons among stream reaches across numerous watersheds are required, or regional assessments are sought.  相似文献   
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