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41.
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   
42.
In this study, we assess the potential of white willow (Salix alba L.) as bioindicator for monitoring of air quality. Therefore, shoot biomass, specific leaf area, stomatal density, stomatal pore surface, and stomatal resistance were assessed from leaves of stem cuttings. The stem cuttings were introduced in two regions in Belgium with a relatively high and a relatively low level of air pollution, i.e., Antwerp city and Zoersel, respectively. In each of these regions, nine sampling points were selected. At each sampling point, three stem cuttings of white willow were planted in potting soil. Shoot biomass and specific leaf area were not significantly different between Antwerp city and Zoersel. Microclimatic differences between the sampling points may have been more important to plant growth than differences in air quality. However, stomatal pore surface and stomatal resistance of white willow were significantly different between Zoersel and Antwerp city. Stomatal pore surface was 20% lower in Antwerp city due to a significant reduction in both stomatal length (?11%) and stomatal width (?14%). Stomatal resistance at the adaxial leaf surface was 17% higher in Antwerp city because of the reduction in stomatal pore surface. Based on these results, we conclude that stomatal characteristics of white willow are potentially useful indicators for air quality.  相似文献   
43.
A test programme was developed to study factors that may influence the maximum pressure during venting developed during deflagration. The factors considered were vent burst pressure, vent mass, ignition source location, discharge ducting, downstream obstructions and water covers.  相似文献   
44.
The increased use of pesticides by container nurseries demands that practices for removal of these potential contaminants from runoff water be examined. Constructed wetlands may be designed to clean runoff water from agricultural production sites, including container nurseries. This study evaluated 14 constructed wetlands cells (1.2 by 4.9 m or 2.4 by 4.9 m, and 30 or 45 cm deep) that collected pesticide runoff from a 465-m2 gravel bed containerized nursery in Baxter, TN. One-half of the cells were vegetated with bulrush, Scirpus validus. The cells were loaded at three rates or flows of 0.240, 0.120, and 0.060 m3 d(-1). Herbicides-simazine (Princep) [2-chloro-4,6-bis(ethylamino)-s-triazine] and metolachlor (Pennant) [2-chloro-N-(2-ethyl-6-methylphenyl)-N-2-methoxy-1-methylethyl-acetamide] -were applied to the gravel portion of the container nursery at rates of 4.78 and 239 kg ha(-1), respectively, 9 July 1998, and at rates of 2.39 and 1.19 kg ha(-1), respectively, 17 May 1999. Pesticides entering the wetland and wetland cell water samples were analyzed daily to determine pesticide removal. At the slower flow rate, which corresponds to lower mass loading and greater hydraulic retention times (HRTs), a greater percentage of pesticides was removed. During the 2-yr period, cells with plants removed 82.4% metolachlor and 77.1% simazine compared with cells without plants, which removed 63.2% metolachlor and 64.3% simazine. At the lowest flow rate and mass loading, wetland cells removed 90.2% metolachlor and 83% simazine. Gravel subsurface flow constructed wetlands removed most of the pesticides in runoff water with the greatest removal occurring at lower flow rates in vegetated cells.  相似文献   
45.
ABSTRACT: Recent technical and scientific advances have increased the potential use of long term, seasonal climate forecasts for improving water resource management. This paper examines the role that forecasts, in particular those based on the El Niño Southern Oscillation (ENSO) cycle, can play in flood planning in the Pacific Northwest. While strong evidence exists of an association between ENSO signals and flooding in the region, this association is open to more than one interpretation depending on: (a) the metric used to test the strength of the association; (b) the definition of critical flood events; (c) site specific features of watersheds; and (d) the decision environment of flood management institutions. A better understanding and appreciation of such ambiguities, both social and statistical, will help facilitate the use of climate forecast information for flood planning and response.  相似文献   
46.
We examined the feasibility of using changes in spatial patterns of ants-distribution on experimental plots as an indicator of response to environmental stress. We produced contour maps based on relative abundances of the three most common genera of ants based on pit-fall trap captures. Relative abundance of Conomyrma spp. decreased, relative abundance of Solenopsis spp. increased, and relative abundance of Pogonomyrmex spp. remained relatively unchanged. The contour maps showed long-term changes in foraging activity and/or distribution of colonies of ants in response to grazing by domestic livestock. This study demonstrated that analysis of spatial patterns of ant activity derived from relative abundances of ants in pit-fall traps provided interpretable data for developing an indicator of exposure to ecosystem stress.  相似文献   
47.
ABSTRACT

Achieving sustainable consumption and production requires a break with current practices in many sectors, including the smartphone sector. Leaders are central actors in catalysing such change by developing, implementing and promoting innovative ideas, products and practices. Not only large but also small enterprises can aspire to assume leadership for sustainability. This contribution explores the environmental, climate and social leadership of the social enterprise Fairphone that seeks to start a movement towards a more sustainable smartphone sector. Endowed with barely any structural power, it relies on other leadership types, especially entrepreneurial leadership, which is based on dialogue, persuasion and coalition-building. Small enterprises can be leaders, but pursuing a goal such as transforming the smartphone sector takes a step-by-step approach targeting different follower groups from suppliers, competitors and consumers to end-of-life processors and policymakers. Those different follower groups are susceptible to different (combinations of) leadership types.  相似文献   
48.
49.
Surficial sediments, midge larvae (Chironomidae, Diptera) and tubificid worms (Tubificidae, Oligochaeta) were collected at 65 sampling sites located in four different river basins in Flanders (Belgium). Concentrations of the trace metals Cu, Zn, Cd and Pb were measured in organisms and sediments by atomic absorption spectrophotometry. Sediments were subjected to a simultaneous extraction scheme to identify trace metal partitioning among various geochemical phases. Three geochemical characteristics of the sediment were analysed; Total Organic Carbon (TOC), Fe oxides and Mn oxides. Non-linear regression models were constructed to determine the relative importance of the different sediment factors contributing to the variation in metal accumulation by the tubificid worms and chironomids. Generally, the amount of variation that could be explained by these models was limited, with coefficients of determination ranging from 0.05 to 0.66. In most cases, metal levels in organisms were positively related to the easily reducible and reducible metal fractions, and negatively related to the TOC and Fe sediment content. The correlations between metal concentrations in tubificid worms and chrinomid larvae were also rather poor, with coefficients of determinations ranging from 0.01 to 0.52. This indicates that understanding the chemistry of the environment does not suffice to predict the concentrations in organisms. Differences in the structural and functional organisation of the organisms, which among others determine the route of exposure, are at least equally important causes of variability in metal availability and accumulation.  相似文献   
50.
Although the spatial variability of throughfall (TF) in forest ecosystems can have important ecological implications, little is known about the driving factors of within-stand TF variability, particularly in deciduous forests. While the spatial variability of TF water amount and H+ deposition under a dominant beech (Fagus sylvatica L.) tree was significantly higher in the leafed period than in the leafless period, the spatial TF deposition patterns of most major ions were similar in both periods. The semiannual TF depositions of all ions other than H+ were significantly positively correlated (r=0.68-0.90, p<0.05) with canopy structure above sample locations throughout the entire year. The amounts of TF water and H+ deposition during the leafed period were negatively correlated with branch cover. We conclude that the spatial heterogeneity of ion deposition under beech was significantly affected by leaves in the growing period and by branches in non-foliated conditions.  相似文献   
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