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271.
Ross Sparks 《Safety Science》2010,48(2):135-144
Methods for detecting outbreaks in the frequency of particular human-related phenomena have typically monitored daily counts for geographical regions. However, age can also be a significant factor in the frequency distribution of particular phenomena. Using data relating to motor vehicle crashes on public roads, this paper offers a methodology for detecting outbreaks that are age group clustered. The transitional Poisson regression model is used to provide day-ahead forecasts (expected values) for daily crash counts across different age groups. Standardized smoothed count departures from their smoothed day-ahead forecasts across all age groups are used to detect systematic outbreaks. The CUSUM of sequential age group standardized scores is used to signal outbreaks that are age-clustered. Potential applications of the developed methodology include early detection of age-related epidemics and unusual increases in work-related accidents.  相似文献   
272.
Human society has experienced, and will continue to experience, extensive loss and damage from worsening anthropogenic climate change. Despite our natural tendencies to categorise and organise, it can be unhelpful to delineate clean boundaries and linear understandings for complex and messy concepts such as loss and damage. Drawing on the perspectives of 42 local and regional Pacific Islander stakeholders, an underexplored resource for understanding loss and damage, we explore the complexity and interconnectedness of non-economic loss and damage (NELD). According to participants, Pacific Islander worldviews, knowledge systems and cosmologies often make it difficult to separate and evaluate NELD independently, challenging the nomenclature of NELD categories developed through international mechanisms. Instead, NELD understandings are often centred on the interdependencies between losses, including the cascading flow-on effects that can occur and the nature of some losses as risk multipliers (i.e. one loss creating the risk for further losses). Most notably, losses to biodiversity, ecosystem services and land are critically linked to, and have cascading effects on, livelihoods, knowledge, ways of life, wellbeing, and culture and heritage. We argue that loss and damage is not always absolute, and that there are NELD that are arguably reparable. Concerning, however, is that biodiversity loss, as a risk multiplier, was considered the least reparable by participants. We put forward that NELD understandings must consider interconnectivity, and that biodiversity and ecosystem conservation and restoration must be the focus for interventions to prevent irreparable and cascading losses from climate change in the Pacific Islands.  相似文献   
273.
This study evaluated the effectiveness of two application rates of a coral-derived surfacing material for both traffic and nontraffic road conditions using simulated rainfall (110–120 mm h−1 for 30–90 min) on 0.75-m (wide) × 5.0-m (long) plots of similar slope (roughly 0.1 m m−1). The coral is a locally available material that has been applied to unpaved roads surfaces on Schoffield Barracks, Oahu, Hawaii (USA), where this experiment was conducted. The simulations show that compared with a bare control plot, the coral-based surface application rates of 80 and 160 kg m−2 (equivalent to only 10- and 20-mm thicknesses) reduced road sediment production by 75% and 95%, respectively, for nontraffic conditions. However, after two passes of the research vehicle during wet conditions, sediment production rates for the two coral treatments were not significantly different from those on the bare road plots. The overall effectiveness of the coral-derived surfacing material is unsatisfactory, primarily because the on-road surface thickness associated with the application rates tested was too small. These rates were selected to bracket those applied to training roads in the study area. Furthermore, the composition of the coral-based material does not facilitate the development of a sealed, erosion-resistant surface. When applied at the low rates tested, the coral material breaks down under normal traffic conditions, thereby losing its ability to counter shearing forces exerted by overland flow on long hillslopes where erosion measures are most needed. These simulations, combined with observations on roads in the study area, indicate that this material is not an appropriate road surfacing material for the site—at least for the low application rates examined. These results are preliminary; extended testing of higher applications rates at the hillslope scale under natural climate and traffic conditions is needed to better judge the effectiveness of this material over time.  相似文献   
274.
The aim of this study was to investigate the application of grapeseed oil, a waste product from the wine industry, as a renewable feedstock to make polyesters and to compare the properties of these materials with those derived from soybean and rapeseed oils. All three oils were epoxidized to give renewable epoxy monomers containing between 3.8 and 4.7 epoxides per molecule. Polymerisation was achieved with cyclic anhydrides catalysed by 4-methyl imidazole at 170 and 210 °C. Polymers produced from methyl tetrahydrophthalic anhydride (Aradur917®) had greater tensile strength and Young’s Modulus (tensile strength = 12.8 MPa, Young’s Modulus = 1005 MPa for grapeseed) than methyl nadic anhydride (MNA) derived materials (5.6 and 468 MPa for grapeseed) due to increased volume of MNA decreasing crosslink density. Soybean and grapeseed oils produced materials with higher tensile strength (5.6–29.3 MPa) than rapeseed derived polyesters (2.5–3.9 MPa) due to a higher epoxide functionality increasing crosslinking. T g’s of the polyesters ranged from ?36 to 62 °C and mirrored the trend in epoxide functionality with grapeseed producing higher T g polymers (?17 to 17 °C) than soybean (?25 to 6 °C) and rapeseed (?36 to ?27 °C). Grapeseed oil showed similar properties to soybean oil in terms of T g, thermal degradation and Young’s Modulus but produced polymers of lower tensile strength. Therefore grapeseed oil would only be a viable substitute for soybean for low stress applications or where thermal properties are more important.  相似文献   
275.
Environmental Economics and Policy Studies - We explore the implications of recent empirical findings about CO2 fertilization and climate sensitivity on the social cost of carbon (SCC) in the FUND...  相似文献   
276.
277.
Growing awareness of polychlorinated biphenyls (PCBs) in legacy caulk and other construction materials of schools has created a need for information on best practices to control human exposures and comply with applicable regulations. A concise review of approaches and techniques for management of building-related PCBs is the focus of this paper. Engineering and administrative controls that block pathways of PCB transport, dilute concentrations of PCBs in indoor air or other exposure media, or establish uses of building space that mitigate exposure can be effective initial responses to identification of PCBs in a building. Mitigation measures also provide time for school officials to plan a longer-term remediation strategy and to secure the necessary resources. These longer-term strategies typically involve removal of caulk or other primary sources of PCBs as well as nearby masonry or other materials contaminated with PCBs by the primary sources. The costs of managing PCB-containing building materials from assessment through ultimate disposal can be substantial. Optimizing the efficacy and cost-effectiveness of remediation programs requires aligning a thorough understanding of sources and exposure pathways with the most appropriate mitigation and abatement methods.  相似文献   
278.
Effective management of large protected conservation areas is challenged by political, institutional and environmental complexity and inconsistency. Knowledge generation and its uptake into management are crucial to address these challenges. We reflect on practice at the interface between science and management of the Greater Blue Mountains World Heritage Area (GBMWHA), which covers approximately 1 million hectares west of Sydney, Australia. Multiple government agencies and other stakeholders are involved in its management, and decision-making is confounded by numerous plans of management and competing values and goals, reflecting the different objectives and responsibilities of stakeholders. To highlight the complexities of the decision-making process for this large area, we draw on the outcomes of a recent collaborative research project and focus on fire regimes and wild-dog control as examples of how existing knowledge is integrated into management. The collaborative research project achieved the objectives of collating and synthesizing biological data for the region; however, transfer of the project’s outcomes to management has proved problematic. Reasons attributed to this include lack of clearly defined management objectives to guide research directions and uptake, and scientific information not being made more understandable and accessible. A key role of a local bridging organisation (e.g., the Blue Mountains World Heritage Institute) in linking science and management is ensuring that research results with management significance can be effectively transmitted to agencies and that outcomes are explained for nonspecialists as well as more widely distributed. We conclude that improved links between science, policy, and management within an adaptive learning-by-doing framework for the GBMWHA would assist the usefulness and uptake of future research.  相似文献   
279.
We studied the lipid dynamics (lipid contents, classes and fatty acids) during oogenesis and early embryogenesis of 7 viviparous and 3 oviparous deepwater chondrichthyans. Mature pre-ovulated ovarian follicles of all species were high in lipid content, indicative of large energetic expenditure and high maternal investment. Larger lipid reserves were found in viviparous dogshark (28–36% wet weight, ww) compared to oviparous chimaeras (19–24% ww) and catshark, F. boardmani (18% ww). Neutral lipids and monounsaturated fatty acids were the main source of lipidic energy during vitellogenesis and gestation. For most species, there was a peak in total lipid content, levels of storage lipids and essential fatty acids at time of ovulation. Interspecific variation of total lipid yolk reserves and lipid class profiles was largely explained by differences in parity mode, reproductive (continuous vs. non-continuous oocytes development) strategy and depth-related physiological adaptations. Fatty acid profiles were less variable among species with the most important fatty acids including: 16:0, 18:1ω9, 20:1ω9, 20:4ω6 and 22:6ω3. These findings provide a greater biochemical understanding of different maternal-embryonic relationships among chondrichthyans, which can be used as a baseline for subsequent comparative studies.  相似文献   
280.
Abstract

Media and academic debates about the environment have increasingly made reference to the so-called ‘eco-preneur’ (‘green entrepreneur’ or ‘environmental entrepreneur’). These discussions encourage us to see the potential of such figures to act as drivers of environmental innovation. Their combination of entrepreneurial zeal and green motivations is seen as providing them with the ability to transcend the usual tensions between business and the environment. In academic circles a new literature is beginning to emerge around this perspective, ‘eco-preneurship’. In this paper we investigate the usefulness of eco-preneurship for understanding environmental innovation. In particular we ask where this literature, supported by popular images in the media, fixes our gaze when we think about environmental innovation in society. And, crucially, what might we be missing by concentrating our attention on these eco-preneurs? The paper concludes by suggesting that environmental innovation is better understood as an inherently messy and complex institutional process, which cannot be reduced to the psychology of entrepreneurial personalities.  相似文献   
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