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31.
House dust has been identified as a major exposure medium for lead (Pb) in children. High levels of Pb in soil and house dust have been recorded at the Bunker Hill Superfund Site (BHSS) in northern Idaho, an historic mining and smelting district. Soil and dust remediation at the site was required; however, regional background soil and dust Pb levels had not been well characterized. The objective of this survey was to determine background house dust Pb levels and to compare those levels with concentrations, and dust and Pb loading rates measured at the BHSS. Soil and house dust samples were collected in five towns demographically similar to the BHSS but unaffected by the mining industry. The background concentrations and loading rates were significantly lower than those observed at the site. House age was a significant factor affecting background soil and house dust Pb concentrations and loading rates.  相似文献   
32.
Silicone rubber sheeting can be used as a passive sampling device for hydrophobic organic contaminants in the environment to determine the available concentrations in water and sediments. Reliable sampler-water partition coefficients are required to determine the sampling rates and the dissolved contaminant concentrations in water and in sediment pore water. Log partition coefficients (logK(sr,w)) for silicone rubber-water have been estimated for 32 polycyclic aromatic hydrocarbons (PAHs), 2 deuterated PAH analogues and 32 chlorobiphenyls (CBs) using the cosolvent method, with methanol as cosolvent. Strong linear relationships were found with literature values for the corresponding log octanol-water partition coefficients (logK(ow)) for both CBs and PAHs, confirming that partitioning into the silicone rubber is strongly determined by the hydrophobicity of the compounds, which suggests logK(ow) is a good predictor of logK(sr,w) and that absorption is the main mechanism for accumulation of analytes into the silicone rubber polymer.  相似文献   
33.
Abstract: We examined six historical specimens of the endangered North Atlantic right whale ( Eubalaena glacialis ) using DNA isolated from documented baleen plates from the late nineteenth and early twentieth centuries. Sequences from the mitochondrial DNA (mtDNA) control region from these samples were compared with those from a near-exhaustive survey (269 of approximately 320 individuals) of the remaining right whales in the western North Atlantic Ocean. Our results suggest that there has been only relatively modest change in maternal lineage diversity over the past century in the North Atlantic right whale population. Any significant reduction in genetic variation in the species most likely occurred prior to the late nineteenth century. One historical specimen was from the last documented female capable of propagating one of the maternal lineages in the population today; no females in the existing population have been found to carry this mtDNA haplotype. Analysis of the only specimens from the eastern North Atlantic right whale population ever to be examined revealed that eastern and western North Atlantic right whales may not have been genetically differentiated populations. Loss of gene diversity experienced by North Atlantic right whales over the last century has been modest, and the six decades of protection have been successful in maintaining much of the maternal lineage diversity that was present in the late nineteenth century.  相似文献   
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35.
Ian Gough 《环境政策》2016,25(1):24-47
A framework is presented for thinking about state intervention in developed capitalist economies in two domains: social policy and environmental policy (and, within that, climate-change policy). Five drivers of welfare state development are identified, the ‘five Is’ of Industrialisation: Interests, Institutions, Ideas/Ideologies, and International Influences. Research applying this framework to the postwar development of welfare states in the OECD is summarised, distinguishing two periods: up to 1980, and from 1980 to 2008. How far this framework can contribute to understanding the rise and differential patterns of environmental governance and intervention across advanced capitalist states since 1970 is explored, before briefly comparing and contrasting the determinants of welfare states and environmental states, identifying common drivers in both domains and regime-specific drivers in each. The same framework is then applied to developments since 2008 and into the near future, sketching two potential configurations and speculating on the conditions for closer, more integrated ‘eco-welfare states’.  相似文献   
36.
Transport infrastructure is particularly vulnerable to climate impacts as it is designed for long operational lives, and both episodic and seasonal conditions contribute to deterioration, disruption and unsafe incidents. There are some examples of adaptation in transportation design, but many communities do not have the capacity to incorporate climate change considerations into infrastructure planning and management. Researchers worked closely with the City of Prince George, in Central British Columbia, Canada, to build on existing work and explore how the City could plan, design, and maintain roads and other structures to account for climate change. A local steering committee was formed, and created and evaluated 23 potential research topics. Two focus areas were selected for further investigation and explored during a workshop with practitioners, researchers, consultants and other representatives. The workshop precipitated an investigation of projected impacts of climate change on road maintenance and road safety, and plans to explore alternative paving techniques. Outcomes of the case study provide insights regarding climate change and local transportation infrastructure, including: how researchers can engage with local experts to explore adaptation; issues local governments perceive as important; and barriers communities face as they attempt to address vulnerabilities.  相似文献   
37.
This study evaluated the microbiocidal efficacy of a cleaning and disinfection (C&D) treatment using stainless-steel coupons applied to three common types of animal mortality transport vehicles when exposed to agricultural conditions. Metal test coupons, inoculated with bacteriophage MS2, were affixed to the undercarriage of three types of animal mortality transport vehicles at various locations. Coupons were grimed by maneuvering the test vehicles down a series of wet dirt roads. Coupons were attached and extracted at various points to evaluate C&D performance with and without grime. C&D efficacy using a water-supplied pressure washing system and a dilute sodium hypochlorite (NaOCl) solution was determined by comparing the difference in recovered viable virus between positive control coupons and test coupons. The results demonstrated a relatively high surface decontamination efficacy, with all but one location showing >5 log reduction of MS2. Coupons located on the roll-off truck's inside-back bumper contained the highest level of grime and resulted in a 4 log reduction of MS2. There was no significant difference in C&D efficacy across vehicle types, but locations impacted by grime and lack of accessibility achieved lower efficacies on average. These findings suggest that common C&D protocols, when applied to farm mortality transport vehicles, are effective. Hard-to-access locations containing high levels of grime may be candidates for additional targeted treatment.  相似文献   
38.
Unprecedented and dramatic transformations are occurring in the Arctic in response to climate change, but academic, public, and political discourse has disproportionately focussed on the most visible and direct aspects of change, including sea ice melt, permafrost thaw, the fate of charismatic megafauna, and the expansion of fisheries. Such narratives disregard the importance of less visible and indirect processes and, in particular, miss the substantive contribution of the shelf seafloor in regulating nutrients and sequestering carbon. Here, we summarise the biogeochemical functioning of the Arctic shelf seafloor before considering how climate change and regional adjustments to human activities may alter its biogeochemical and ecological dynamics, including ecosystem function, carbon burial, or nutrient recycling. We highlight the importance of the Arctic benthic system in mitigating climatic and anthropogenic change and, with a focus on the Barents Sea, offer some observations and our perspectives on future management and policy.  相似文献   
39.
This scoping review provides a summary of research findings on social support dynamics in the wake of disasters that occurred on the continent of Australia and Oceania between 1983 and 2013. Forty-one studies, quantitative and qualitative, were summarised, investigating different facets of post-disaster supportive interactions. All inquiries assessed disasters resulting from natural hazards, with the majority of them conducted following events in Australia and New Zealand. The review revealed similar patterns of post-disaster social support dynamics that routinely unfold after disastrous incidents all over the world. Consistent with the disaster mental health literature, the documentation of social support mobilisation and social support deterioration processes was common. Salutary direct effects of supportive behaviours on post-disaster psychological distress were also highly evident. Most studies, however, posed research questions or hypotheses that lacked empirical or theoretical grounding. In conclusion, the review offers several recommendations on how to advance research on post-disaster social support.  相似文献   
40.
The distribution and composition of hydrocarbons in sediment from the Fladen Ground oilfield in the northern North Sea have been investigated. The total PAH concentrations (2- to 6-ring parent and alkylated PAHs, including the 16 US EPA PAHs) in sediments were relatively low (<100 microg kg(-1) dry weight). The PAH, the Forties crude and diesel oil equivalent concentrations were generally higher in sediment of fine grain size and higher organic carbon concentration. PAH distributions and concentration ratios indicated a predominantly pyrolytic input, being dominated by the heavier, more persistent, 5- and 6-ring compounds, and with a high proportion of parent PAHs. The n-alkane profiles of a number of the sediments contained small, high boiling point, UCMs, indicative of weathered oil arising from a limited petrogenic input. The geochemical biomarker profiles of the sediments that contained UCMs showed a small bisnorhopane peak and a high proportion of norhopane relative to hopane, indicating that there was contamination from both Middle Eastern and North Sea oils. Therefore contamination was not directly as a result of oil exploration activity in the area. The most likely source of petrogenic contamination was from general shipping activity.  相似文献   
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