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131.
The objectives of this study were to identify components of accidents that cause the most disability and to discover the principal sources of injuries treated in the fracture clinics. Patients attending fracture clinics of the Royal Liverpool University Hospital were interviewed using a portable computer-based questionnaire, the Merseyside Accident Information Model (MAIM). Patients were followed up by telephone interview or letter to enquire about disability continuing after discharge. Disability was measured by the pre-accident to post-discharge changes in scores for 11 normal functions. Of the 1326 patients interviewed, 900 (68%) were successfully followed up and 37% reported disability after discharge. First events ‘tripping’, ‘slipping’ and ‘other underfoot events’ accounted for 433 patients (194 reporting disability), and ‘collapsed/fainted — no other event' for 66 patients (27 reporting disability). Activities at the time of accident most frequently associated with disability involved moving about on foot. Among first event objects, ground surfaces and underfoot hazards were reported in 35%. Sources of injuries included underfoot accidents (48%), sport (13%), and transport accidents (12%.). Underfoot accidents contributed to 58% of patients reporting disability, sport 6% and transport accidents 11%. Underfoot accidents together with ‘collapsed/fainted — no other event’ accounted for 79% of female patients reporting disability and 50% of men. Such data could be used for cost-effective targeting of preventative measures, and to study the effectiveness of accident prevention initiatives.  相似文献   
132.
More than 273 tonnes of cadmium have been added to Western Australian ecosystems through the application of superphosphate fertilisers since 1982. Fifty percent of this is water soluble and therefore eventually leaches into waterbodies and accumulates in the sediments. From this source, it enters the food web through algae and benthic animals and may ultimately be passed to humans. This is reflected in the cadmium levels of the freshwater mussels (Westralunio carteri) that exceeded statutory Australia New Zealand Food Authority (ANZFA) guidelines for Maximum Permissible Concentrations (MPCs) with respect to human consumption. The cadmium levels bioaccumulated in freshwater mussels elevated with increasing catchment clearing, being highest in degraded catchments. The MPC for Cd in crustaceans have recently been removed, yet tissues within the freshwater crayfish (Cherax tenuimanus) frequently exceeded the old MPC (0·2 μCd g−1wet weight). Marron are sometimes consumed in considerable quantities and the risk to human health posed by a high Cd intake is briefly summarised. Finally, a number of management options concerned with reducing the level of Cd from fertilisers passing to humans are reviewed.  相似文献   
133.
Shrub-Steppe Early Succession Following Juniper Cutting and Prescribed Fire   总被引:1,自引:0,他引:1  
Pinus-Juniperus L. (Piñon-juniper) woodlands of the western United States have expanded in area nearly 10-fold since the late 1800’s. Juniperus occidentalis ssp. occidentalis Hook. (western juniper) dominance in sagebrush steppe has several negative consequences, including reductions in herbaceous production and diversity, decreased wildlife habitat, and higher erosion and runoff potentials. Prescribed fire and mechanical tree removal are the main methods used to control J. occidentalis and restore sagebrush steppe. However, mature woodlands become difficult to prescribe burn because of the lack of understory fuels. We evaluated partial cutting of the woodlands (cutting 25–50% of the trees) to increase surface fuels, followed by prescribed fire treatments in late successional J. occidentalis woodlands of southwest Idaho to assess understory recovery. The study was conducted in two different plant associations and evaluated what percentage of the woodland required preparatory cutting to eliminate remaining J. occidentalis by prescribed fire, determined the impacts of fire to understory species, and examined early post-fire successional dynamics. The study demonstrated that late successional J. occidentalis woodlands can be burned after pre-cutting only a portion of the trees. Early succession in the cut-and-burn treatments were dominated by native annual and perennial forbs, in part due to high mortality of perennial bunchgrasses. By the third year after fire the number of establishing perennial grass seedlings indicated that both associations would achieve full herbaceous recovery. Cutting-prescribed fire combinations are an effective means for controlling encroaching late successional J. occidentalis and restoring herbaceous plant communities. However, land managers should recognize that there are potential problems associated with cutting-prescribed fire applications when invasive weeds are present.  相似文献   
134.
Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis Beetle & Young) communities frequently are mowed in an attempt to increase perennial herbaceous vegetation. However, there is limited information as to whether expected benefits of mowing are realized when applied to Wyoming big sagebrush communities with intact understory vegetation. We compared vegetation and soil nutrient concentrations in mowed and undisturbed reference plots in Wyoming big sagebrush plant communities at eight sites for three years post-treatment. Mowing generally did not increase perennial herbaceous vegetation cover, density, or biomass production (P > 0.05). Annual forbs and exotic annual grasses were generally greater in the mowed compared to the reference treatment (P < 0.05). By the third year post-treatment annual forb and annual grass biomass production was more than nine and sevenfold higher in the mowed than reference treatment, respectively. Our results imply that the application of mowing treatments in Wyoming big sagebrush plant communities does not increase perennial herbaceous vegetation, but may increase the risk that exotic annual grasses will dominate the herbaceous vegetation. We suggest that mowing Wyoming big sagebrush communities with intact understories does not produce the expected benefits. However, the applicability of our results to Wyoming big sagebrush communities with greater sagebrush cover and/or degraded understories needs to be evaluated.  相似文献   
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136.
Introduction: Sleep-deprived driving can be as dangerous as alcohol-impaired driving, however, little is known about attitudes toward sleep-deprived drivers. This study examined the extent to which young drivers regard sleep-deprived compared to drinking drivers as culpable for a crash, and how their perceptions of driving while in these conditions differ. Method: University student participants (N = 295; M = 20.4 years, SD = 1.3; 81% women) were randomly assigned to read one of five fatal motor-vehicle crash scenarios, which differed by aspects of the driver's condition. Culpability ratings for the drinking driver were higher than those for the sleep-deprived driver. Results: Qualitative findings revealed that driving while sleep-deprived was viewed as understandable, and driving after drinking was viewed as definitely wrong. The dangers of sleep-deprived driving remain under-recognized.  相似文献   
137.
The European earwig, Forficula auricularia is an invasive insect found in many temperate regions of the world and is regarded as an urban and agricultural pest of numerous crops. Several studies have shown that F. auricularia aggregate in large numbers with the use of an aggregation pheromone. However, the identity of compounds which constitute the pheromone remains elusive. Our aim was to isolate and identify the aggregation pheromone used by F. auricularia using both solvent washes of individuals and thermal desorption of substrates exposed to earwigs. Solvent washes of male, female and juvenile earwigs isolated 51 different branched and unbranched alkanes, alkenes and alkadienes. Substrates exposed to aggregating field populations in situ were demonstrated to be attractive to earwigs after less than 24 h of exposure. Analysis of these substrates using thermal desorption and solvent washes showed that hydrocarbons were the only detectable compounds laid down by earwigs on these surfaces. Significant behavioural responses were observed to synthetic blends of the unsaturated hydrocarbons containing (Z)-7-tricosene, (Z)-9-tricosene, (Z)-7-pentacosene and (Z)-9-pentacosene at ≥25 insect equivalents in field-based bioassays. However, behavioural responses to these blends proved inconsistent particularly later in the field season, possibly due to a missing component within the pheromone blend or plasticity in the pheromones production and response.  相似文献   
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139.
Nitrogen cycling in a natural planktonic food chain was followed before and after perturbation by copper (10 g l-1). Observations were separated into effects from artificial containment of the food chain and effects from the addition of copper. An initial reduction of seston-N and subsequent recovery, uniformly high settling rates of suspended particulate-N, and general decrease in zooplankton-N were attributed to the physical limitations imposed by the enclosures (e.g. elimination of normal mixing processes). Acute inhibition of nitrate assimilation by the seston, acute elevation of seston-N settling and chronic inhibition of zooplankton feeding, along with accelerated decline in zooplankton stocks, were attributed to copper stress. Since zooplankton stocks and fluxes were most drastically affected by copper, its overall effect on N-cycling through the planktonic food chain would depend largely upon the importance of zooplankton in regulating the production of the remaining seston.  相似文献   
140.
Policies designed to conserve sites of nature conservation importance are an important aspect of city planning in the UK. London has led the way in putting in place a spatial hierarchy of sites of nature conservation importance designed to protect wildlife habitats from development. Some wasteland habitats associated with derelict and vacant land receive protection in this way but development pressure on these so-called 'brownfield sites' is high and is likely to continue. This paper examines how conservation professionals in the private, public and voluntary sectors are responding to the threats of biodiversity loss and opportunities for habitat creation posed by re-development of brownfield sites. The study draws on in-depth interviews conducted with conservation professionals and the practices employed by ecological advisers employed by developers seeking to re-develop wasteland sites. It finds that practitioners are negotiating their role in the re-development process in different ways. Key issues relate to the role of ecological science in codifying wasteland habitats, uncertainties about how best to evaluate the conservation importance of such sites and the strategies and tactics employed by different practitioners as they seek to mobilise a range of knowledges and practices to secure ecologically sensitive proposals. Scientific knowledge about wasteland habitats has not stabilised in ways that can consistently inform conservation policy and practice. As a result biodiversity issues of wasteland sites are often discounted in the re-development process. Investment in studies of the basic ecology of urban wastelands could provide a firmer scientific foundation on which conservation policies could build. At the same time, many conservation professionals involved in urban re-development are struggling to promote a pro-active approach to secure environmentally sensitive development. The knowledge and co-operation networks being mobilised to support this approach are fluid and unstable, and favourable development outcomes as yet are few. Formalising these networks to achieve more effective engagements with developers and the construction industry could consolidate ecological practices designed to conserve and re-create the biodiversity of wasteland habitats.  相似文献   
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