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81.
Ultrasound examination due to an elevated maternal serum alpha-fetoprotein level showed lower extremity asymmetry. The findings were felt to be consistent with Klippel—Trénaunay—Weber syndrome. The pregnancy was terminated based on these findings. The ultrasound findings, confirming post-mortem examination, and counselling issues are discussed.  相似文献   
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What resources should be committed to the control of invasive species? This study is based on a survey of nature conservation and forestry authorities, wildlife trusts and private landowners which investigated the extent of the ecological and economic impacts of the invasive non-native plant Rhododendron ponticum in the British Isles. There are data on 52,000 ha of land affected by R. ponticum, more than 30,000 ha of it in nature reserves. For nearly all nature reserves, displacement of native species and habitat changes were both reported. In 2001, respondents controlled 1275 ha of R. ponticum at a cost of pound 670,924. To test the optimality of this, we apply a model of social expenditure. The external costs of R. ponticum control are estimated from the probability that it will spread to contiguous sites and the damage done on invaded sites. These are then used to calculate the socially optimal level of expenditure on R. ponticum control, and the funding gap it identified by comparing the result with current levels of expenditure. The results suggest that a socially optimal level of control effort requires a significant increase in social funding for R. ponticum control, although the size of the increase varies between landholders.  相似文献   
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INTRODUCTION: Compared to younger age groups, older people are more likely to be seriously injured or to die as a result of a traffic crash. METHOD: The aim of the study is to examine the impact of environmental, vehicle, crash, and driver characteristics on injury severity in older drivers involved in traffic crashes by using recently linked police crash records and hospitalization data from New South Wales, Australia. The severity of injury resulting from traffic crashes was measured using the International Classification of Diseases, 10th revision (ICD-10) Injury Severity Score (ICISS). RESULTS: Multivariate analysis identified rurality, presence of complex intersections, road speed limit, driver error, speeding, and seat belt use as independent predictors of injury severity in older people. The type of intersection configuration explained over half of the observed variations in injury severity. IMPACT ON INDUSTRY: Environmental modification such as intersection treatments might contribute to a decrease in the severity of injury in older people involved in road crashes.  相似文献   
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The risk estimates calculated from the conventional risk assessment method usually are compound specific and provide limited information for source-specific air quality control. We used a risk apportionment approach, which is a combination of receptor modeling and risk assessment, to estimate source-specific lifetime excess cancer risks of selected hazardous air pollutants. We analyzed the speciated PM(2.5) and VOCs data collected at the Beacon Hill in Seattle, WA between 2000 and 2004 with the Multilinear Engine to first quantify source contributions to the mixture of hazardous air pollutants (HAPs) in terms of mass concentrations. The cancer risk from exposure to each source was then calculated as the sum of all available species' cancer risks in the source feature. We also adopted the bootstrapping technique for the uncertainty analysis. The results showed that the overall cancer risk was 6.09 x 10(-5), with the background (1.61 x 10(-5)), diesel (9.82 x 10(-6)) and wood burning (9.45 x 10(-6)) sources being the primary risk sources. The PM(2.5) mass concentration contributed 20% of the total risk. The 5th percentile of the risk estimates of all sources other than marine and soil were higher than 110(-6). It was also found that the diesel and wood burning sources presented similar cancer risks although the diesel exhaust contributed less to the PM(2.5) mass concentration than the wood burning. This highlights the additional value from such a risk apportionment approach that could be utilized for prioritizing control strategies to reduce the highest population health risks from exposure to HAPs.  相似文献   
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Epidemiological studies of exposure to vegetation fire smoke are often limited by the availability of accurate exposure data. This paper describes a systematic framework for retrospectively identifying the cause of air pollution events to facilitate a long, multicenter analysis of the public health effects of vegetation fire smoke pollution in Australia. Pollution events were statistically defined as any day at or above the 95th percentile of the 24-hr average concentration of particulate matter (PM). These were identified for six cities from three distinct ecoclimatic regions of Australia. The dates of each event were then crosschecked against a range of information sources, including online newspaper archives, government and research agency records, satellite imagery, and aerosol optical thickness measures to identify the cause for the excess particulate pollution. Pollution events occurred most frequently during summer for cities in subtropical and arid regions and during winter for cities in temperate regions. A cause for high PM on 67% of days examined in the city of Sydney was found, and 94% of these could be attributed to landscape fire smoke. Results were similar for cities in other subtropical and arid locations. Identification of the cause of pollution events was much lower in colder temperate regions where fire activity is less frequent. Bushfires were the most frequent cause of extreme pollution events in cities located in subtropical and arid regions of Australia. Although identification of pollution episodes was greatly improved by the use of multiple sources of information, satellite imagery was the most useful tool for identifying bushfire smoke pollution events.  相似文献   
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In Kakadu National Park, a World Heritage property in the Australian monsoon tropics 250 km to the east of Darwin, a number of recent studies have shown that woody encroachment (expansion of woody communities) and densification (increased biomass in woody communities) has occurred in the last 40 years. The cause of this increase in woody biomass is poorly understood, but possibly associated with the control of invasive Asian water buffalo, trend to higher rainfall, and increased frequency of fires. Mangroves provide an important context to understand these landscape changes, given that they are unaffected by fire or feral water buffalo. We examine change in mangrove distribution in a series of coastal tropical swamps fringing Darwin, Northern Territory, Australia over a 30-year period using a series of 7 aerial photographs spanning 23 years from 1974 and a 2004 high-resolution satellite image. In late 1974, Darwin was impacted by an intense tropical cyclone. Vegetation at 3,000 randomly placed points was manually classified, and a multinomial logistic model was used to asses the impact of landscape position (coastal, intertidal, and upper-tidal) and swamp on mangrove change between 1974 and 2004. Over the study period, there was instability and slight mangrove loss at the coast, stability in the intertidal zone, and mangrove gain in the upper-tidal zone, with an overall increase in mangrove presence of 16.2% above the pre-cyclone distribution. A swamp that was impacted by drainage works for mosquito control and the construction of a sewage treatment plant showed a greater mangrove increase than the two unmodified swamps. The mangrove expansion is consistent with woody encroachment observed in nearby but ecologically distinct systems. Plausible causes for this change include changed local hydrology, changes in sea level, and elevated atmospheric CO2 concentrations.  相似文献   
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