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301.
The Journal of Safety Research has partnered with the Injury Center at the Centers for Disease Control and Prevention (CDC) in Atlanta, Georgia, USA, to briefly report on some of the latest findings in the research community. This report is the sixth in a series of CDC articles. This conference on Hip Protector Use was held at Boston University in June, 2004 under the sponsorship of the Injury Center. Hip fractures from falls are a major threat to the health and well-being of older adults. One approach to hip fracture prevention is the use of hip protectors (HPs), soft padding or hard shells embedded within specially designed underwear. This conference brought together experts to discuss the efficacy and barriers to using HP. Conclusions from the conference included the need for HP product specifications and standards of safety and efficacy, testing protocols, and efficacy trials. While no single entity was identified to advance these initiatives, this effort should be international and should involve collaboration between researchers, health care providers and policy-makers, and HP manufacturers. Plans are already underway for a second international conference in Europe to follow-up these recommendations and develop strategies for implementation.  相似文献   
302.
Government intervention schemes in the form of policy instruments and financial incentives or rebates can have a major influence on the adoption of technologies by residential consumers to reduce their natural resource consumption and greenhouse gas emissions. However, the pattern and rate of consumer uptake of voluntary schemes are not always well-understood or easily taken into account in future scenarios analyses. This paper presents an innovative extension of the Bass diffusion model that has been integrated with multi-criteria analysis to enable explicit consideration and balancing of the impacts of technology cost, financial benefits, demographic suitability and household income on the likelihood of adoption. This ‘Intervention Options’ model is formulated into a constrained integer programming problem to allow optimisation of the size and timing of government rebates to maximise adoption rate and, ultimately, environmental benefits. The model’s capability is demonstrated using an Australian case study of 25,000 households, and historical information on the uptake of solar hot water and solar photovoltaic panels in Brisbane, Queensland. Case study results reveal new insights and important context-relevant trends that could assist policy makers to substantially improve the effectiveness of intervention schemes to achieve environmental goals within desired budgets.  相似文献   
303.
A stochastistic, Weibull probability model was developed and verified to simulate the underlying frequency distributions of hourly ozone (O3) concentrations (exposure dynamics) using the single, weekly mean values obtained from a passive (sodium nitrite absorbent) sampler. The simulation was based on the data derived from a co-located continuous monitor. Although at the moment the model output may be considered as being specific to the elevation and location of the study site, the results were extremely good. This effort for the approximation of the O3 exposure dynamics can be extended to other sites with similar data sets and in developing a generalized understanding of the stochastic O3 exposure-plant response relationships, conferring measurable benefits to the future use of passive O3 samplers, in the absence of continuous monitoring.  相似文献   
304.
Phosphogypsum (PG), a by-product of the phosphate fertilizer industry, reduces N losses when added to composting livestock manure, but its impact on greenhouse gas emissions is unclear. The objective of this research was to assess the effects of PG addition on greenhouse gas emissions during cattle feedlot manure composting. Sand was used as a filler material for comparison. The seven treatments were PG10, PG20, PG30, S10, S20, and S30, representing the rate of PG or sand addition at 10, 20, or 30% of manure dry weight and a check treatment (no PG or sand) with three replications. The manure treatments were composted in open windrows and turned five times during a 134-d period. Addition of PG significantly increased electrical conductivity (EC) and decreased pH in the final compost. Total carbon (TC), total nitrogen (TN), and mineral nitrogen contents in the final composted product were not affected by the addition of PG or sand. From 40 to 54% of initial TC was lost during composting, mostly as CO(2), with CH(4) accounting for <14%. The addition of PG significantly reduced CH(4) emissions, which decreased exponentially with the compost total sulfur (TS) content. The emission of N(2)O accounted for <0.2% of initial TN in the manure, increasing as compost pH decreased from alkaline to near neutral. Based on the total greenhouse gas budget, PG addition reduced greenhouse gas emissions (CO(2)-C equivalent) during composting of livestock manure by at least 58%, primarily due to reduced CH(4) emission.  相似文献   
305.
Each year, large quantities of pharmaceuticals and personal care products (PPCPs) are used worldwide. Once conveyed to wastewater treatment plants, PPCPs can remain unchanged or undergo partial or complete transformation during wastewater treatment processes before discharge into the environment via effluent and biosolids for land application. Biosolids can be a major sink for some PPCPs. Previous investigations have indicated that land application of biosolids may be a potential important route through which PPCPs enter the environment. However, no information is available on exactly how closely the concentrations of PPCPs in the environmental media are related to the land application of PPCP-containing biosolids. This paper reviews currently available information on the occurrence of PPCPs in biosolids, methods of analysis, the potential fate of PPCPs in biosolids-applied soils, and composting as a potential means for removal of PPCPs from biosolids.  相似文献   
306.
Synthetic polymers are important to the packaging industry but their use raises aesthetic and environmental concerns, particularly with regard to solid waste accumulation problems and the threat to wildlife. Some concerns are addressed by attention to problems associated with source reduction, incineration, recycling and landfill. Others are addressed by the development of new biodegradable polymers either alone or in blends. Materials used for biodegradable polymers include various forms of starch and products derived from it, biopolyesters and some synthetic polymers. Starch is rapidly metabolised and is an excellent base material for polymer blends or for infill of more environmentally inert polymers where it is metabolised to leave less residual polymer on biodegradation. This should help to improve the environmental impact of waste disposal. A number of standard methods have been developed to estimate the extent of biodegradability of polymers under various conditions and with a variety of organisms. They tend to be used mainly in the countries where they were developed but there is much overlap between the standards of different countries and wide scope for development of consistent and international standards.  相似文献   
307.
Abstract: The effectiveness of measuring lawn sprinkler application rates using the catch‐can test was evaluated. A survey of sources recommending the catch‐can test for measuring application rates show that catch‐can test procedures differ in the collector type, collector placement, number of collectors, and test duration. Analyses of catch‐can tests were performed to address these procedural differences, with emphasis on the type and number of collectors required to provide a reasonable level of confidence in test results. The accuracy of the catch‐can test generally improves as the number of randomly placed collectors increases. In order to achieve an accuracy of ±25% for 90 out of 100 catch‐can tests, the number of randomly placed collectors required ranged from 6 to over 50 for hand‐move systems, while for in‐ground systems, the number of randomly placed collectors required ranged from 2 to 8, depending on the pressure and percent overlap of the water distribution pattern. As long as a reasonable number of collectors were used when performing a catch‐can test, no consistent differences were observed in catch‐can test results due to type of collectors when using tuna fish cans, soup cans, or coffee mugs.  相似文献   
308.
In 57 l-m2 samples within a meadow of Halodule wrightii in Bogue Sound, North Carolina, USA, densities of the clams Mercenaria mercenaria and Chione cancellata were positively associated with seagrass cover. Where seagrass was experimentally removed, marked individuals of both clam species exhibited high rates of mortality in fine sand sediments during two successive experiments spanning 13 months. In the unaltered (control) seagrass meadow, M. mercenaria density remained constant over 13 months and C. cancellata density declined at a slower rate than in the unvegetated plots. Seagrass provides these clams with a refuge from whelk (Busycon carica, B. contrarium, and B. canaliculatum) predation, the major cause of mortality and population decline in experimentally unvegetated plots. In 2 factorial field experiments in unvegetated substratum in which densities of M. mercenaria and C. cancellata were varied independently, first over 5 levels (0 X, 1/2X, 1 X, 2 X, 4 X) and subsequently over 4 levels (0 X, 1/4 X, 1 X, 4 X), there was no repeatable intra- or interspecific effect of density on percent survival, or on the rate of any mortality type. Whelk predation fell preferentially on larger size classes of both species, whereas factors which contribute to clam disappearance usually acted more intensely on smaller sizes. Experimental exclusion of large predators by caging demonstrated that even in unvegetated substratum survivorship of both clam species was high in the absence of whelks and other predators. Individuals of C. cancellata live closer to the sediment surface than those of M. mercenaria, which may explain why seagrass does not serve as effectively to protect them from whelk predation. The mechanism of whelk inhibition may depend upon sediment binding by the H. wrightii root mat, which produces a demonstrable decrease in the physical penetrability of surface sediments.  相似文献   
309.
The behavior of individuals currently living will generally have long-term consequences that affect the well-being of those who will come to live in the future. Intergenerational interdependencies of this nature raise difficult moral issues because only the current generation is in a position to decide on actions that will determine the nature of the world in which future generations will live. Although most are willing to attach some weight to the interests of future generations, many would argue that it is not necessary to treat these interests as equivalent to those of the current generation. A common approach in this context is to use a system of discounting to evaluate future benefits and harms. This paper assesses the logic of discounting drawing on the writings of economists and philosophers. Much of the economic literature concerns the choice of an appropriate social discount rate. The social discount rate can be taken to reflect beliefs about the rights of future generations, a subject that has been extensively debated in the phioosophic literature. The writings of both economists and philosophers concerned with the weight to attach to the interests of future generations are reviewed and evaluated in this paper and the implications for environmental policy are discussed.  相似文献   
310.
In response to protection needs in class I wilderness areas, forest land managers of the USDA Forest Service must provide input to regulatory agencies regarding air pollutant impacts on air quality-related values. Regional workshops have been convened for land managers and scientists to discuss the aspects and extent of wilderness protection needs. Previous experience with a national workshop indicated that a document summarizing workshop discussions will have little operational utility. An alternative is to create a knowledge-based analytical system, in addition to the document, to aid land managers in assessing effects of air pollutants on wilderness. Knowledge-based methods were used to design and conduct regional workshops in the western United States. Extracting knowledge from a large number of workshop participants required careful planning of workshop discussions. Knowledge elicitation methods helped with this task. This knowledge-based approach appears to be effective for focusing group discussions and collecting knowledge from large groups of specialists.  相似文献   
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