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91.
Stochastic transfer of information in a hierarchy of simulators is offered as a conceptual approach for assessing forest responses to changing climate and air quality across 13 southeastern states of the USA. This assessment approach combines geographic information system and Monte Carlo capabilities with several scales of computer modeling for southern pine species and eastern deciduous forests. Outputs, such as forest production, evapotranspiration and carbon pools, may be compared statistically for alternative equilibrium or transient scenarios providing a statistical basis for decision making in regional assessments. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
92.
Concentrations of polybrominated diphenyl ethers (PBDEs), and organochlorine pesticides (OCPs; DDTs, HCHs, CHLs, and HCB) were measured in human breast milk samples collected across Massachusetts, USA, in 2004. Seventeen PBDE congeners were found in the samples, ranging in concentration from 0.06 to 1910 ng g(-1) lipid wt. BDE-47 (2,2',4,4'-tetraBDE), BDE-99 (2,2',4,4',5-pentaBDE), and BDE-100 (2,2',4,4',6-pentaBDE) were the major congeners detected in breast milk samples. Overall mean (+/-SD) concentrations of DDTs, HCHs, CHLs, and HCB were 64.5 +/- 75, 18.9 +/- 19, 32.4 +/- 36, and 2.3 +/- 2.2 ng g(-1) lipid wt, respectively. Concentrations of PBDEs were strongly correlated with concentrations of OCPs in the samples. Based on the concentrations of organohalogens and the intake rates of breast milk by infants in the United States, daily ingestion rates of contaminants were calculated. The median ingestion rates for PBDEs, HCHs, DDTs, CHLs, and HCB were 4.0, 212, 141, 44, and 5.79 ng kg(-1) body wt day(-1), respectively. The estimated daily intake of organohalogens by infants was compared with threshold reference values suggested by the United States Environmental Protection Agency (USEPA) and the Agency for Toxic Substances and Disease Registry (ATSDR), for calculation of hazard quotients (HQs). HQs for individual organohalogens and the sum of HQ for all organohalogens were calculated as HQ indices (HQI). The results suggest that one or more of the contaminants analyzed in this study exceeded the threshold reference values in at least 26% of the breast milk samples.  相似文献   
93.
Approximately 25% of globally reported shark catches occur in Atlantic pelagic longline fisheries. Strong declines in shark populations have been detected in the North Atlantic, whereas in the South Atlantic the situation is less clear, although fishing effort has been increasing in this region since the late 1970s. We synthesized information on shark catch rates (based on 871,177 sharks caught on 86,492 longline sets) for the major species caught by multiple fleets in the South Atlantic between 1979 and 2011. We complied records from fishing logbooks of fishing companies, fishers, and onboard observers that were supplied to Brazilian institutions. By using exploratory data analysis and literature sources, we identified 3 phases of exploitation in these data (Supporting Information). From 1979 to 1997 (phase A), 5 fleets (40 vessels) fished mainly for tunas. From 1998 to 2008 (phase B), 20 fleets (100 vessels) fished for tunas, swordfishes, and sharks. From 2008 to 2011 (phase C), 3 fleets (30 vessels) fished for multiple species, but restrictive measures were implemented. We used generalized linear models to standardize catch rates and identify trends in each of these phases. Shark catch rates increased from 1979 to 1997, when fishing effort was low, decreased from 1998 to 2008, when fishing effort increased substantially, and remained stable or increased from 2008 to 2011, when fishing effort was again low. Our results indicate that most shark populations affected by longlines in the South Atlantic are currently depleted, but these populations may recover if fishing effort is reduced accordingly. In this context, it is problematic that comprehensive data collection, monitoring, and management of these fisheries ceased after 2012. Concurrently with the fact that Brazil is newly identified by FAO among the largest (and in fastest expansion) shark sub‐products consumer market worldwide.  相似文献   
94.
Poff, Boris, Karen A. Koestner, Daniel G. Neary, and Victoria Henderson, 2011. Threats to Riparian Ecosystems in Western North America: An Analysis of Existing Literature. Journal of the American Water Resources Association (JAWRA) 47(6):1241–1254. DOI: 10.1111/j.1752‐1688.2011.00571.x Abstract: A total of 453 journal articles, reports, books, and book chapters addressing threats to riparian ecosystems in western North America were analyzed to identify, quantify, and qualify the major threats to these ecosystems as represented in the existing literature. Publications were identified either as research, policy, literature review, historical comparison, or management papers. All papers were evaluated based on year of publication, area of interest, and type(s) of threats addressed. Research papers, however, were assessed in more depth. The publications ranged from the 1930s to 2010 and addressed the following threats: dams, pollution (point and nonpoint), grazing, land use change, timber harvesting, water diversion, road construction, recreation, mining, groundwater pumping, invasive species, climate change, salinity, fire, insect and diseases, woody encroachment, watershed degradation, elimination of native vegetation, beavers, fire suppression, and fuel management. While the types of threats vary on spatial and temporal scales, some persist through decades in western North America. This analysis shows that grazing has been perceived as a dominant threat since the 1980s, but has been diminishing in the past decade, while invasive species, dams and, in recent years, climate change are increasingly represented in the literature as threats to riparian ecosystems in western North America.  相似文献   
95.
96.
This study provides and meta‐analytically examines an organizing framework and theoretical model of work–family conflict. Results, based on 1080 correlations from 178 samples, indicate that work role stressors (job stressors, role conflict, role ambiguity, role overload, time demands), work role involvement (job involvement, work interest/centrality), work social support (organizational support, supervisor support, coworker support), work characteristics (task variety, job autonomy, family friendly organization), and personality (internal locus of control, negative affect/neuroticism) are antecedents of work‐to‐family conflict (WFC); while family role stressors (family stressors, role conflict, role ambiguity, role overload, time demands, parental demands, number of children/dependents), family social support (family support, spousal support), family characteristics (family climate), and personality (internal locus of control, negative affect/neuroticism) are antecedents of family‐to‐work conflict (FWC). In addition to hypothesized results, a revised model based on study findings indicates that work role stressors (job stressors, role conflict, role ambiguity, role overload) and work social support (organizational support, supervisor support, coworker support) are predictors of FWC; while family role stressors (family stressors, role conflict, role ambiguity, role overload), family involvement (family interest/centrality), family social support (family support, spousal support), and family characteristics (family climate) are predictors of WFC. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
97.
Nowadays every piece of working equipment and tools has to comply with safety standards and laws. This study investigated multi-criteria methods for selecting working equipment in order to optimize performance and occupational safety. The multi-criteria decision-making (MDCM) method was applied to the problem of selecting optimal working equipment using four different criterion weighting approaches (direct weighting, revised Simos procedure, Fuller’s triangle and analytic hierarchy process). Groups of economic, technical and safety criteria were defined and five weighting scenarios were developed. Although the four weighting methods produced similar results, in some situations they produced different criterion weighting factors. The final output of the MCDM method was the identification of the optimal forklift in the five weighting scenarios. Although we have applied the MCDM method to a forklift selection problem, it can be applied to all sorts of working equipment in contexts where economic, technical and safety selection criteria can be identified.  相似文献   
98.
Human hair samples from male and female people aged 6-85 years, as well as muscle of crabs (Callinectes sapidus and Callinectes bocourti) were collected from different fishing places along the Caribbean coastal shoreline of Colombia and analyzed for total mercury (T-Hg) in order to establish the impact of mercury-polluted sediments in Cartagena bay on the ecosystem. Hair T-Hg in inhabitants varied between 0.1 and 21.8 microg/g, with average and median of 1.52 microg/g and 1.1 microg/g, respectively. Differences between sampling locations were significant (P<0.01) and median values decreased in the order: Ca?o del Oro (1.5 microg/g)相似文献   
99.
100.
Sea ports and the related maritime activities (e.g. shipping, shipbuilding, etc.) are one of the main driver of Europe’s growth, jobs, competitiveness and prosperity. The continuously growth of shipping sectors has however introduced some environmental concerns, particularly with respect to ship-generated waste management. The port of Koper, one of the major ports on the northern Adriatic Coast, is the focus of this study. In this paper, a life cycle assessment was performed to identify and quantify the environmental impacts caused by the ship-generated waste management of port of Koper. Carcinogens substance (e.g. dioxins) and inorganic emissions, especially heavy metals, resulted to be the most critical environmental issues, while the fossil fuels consumption is reduced by recovery of ship-generated oils. Moreover, the final treatment of ship waste was found to be critical phase of the management, and the landfill have a significant contribute to the overall environmental load. These results can be useful in the identification of the best practices and in the implementation of waste management plans in ports.  相似文献   
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