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141.
OBJECTIVE: The study aimed to explore the distribution and correlates of subjective sleepiness among the general night-time driving population. METHODS: The survey took place in three British Columbia communities in June 2003 between 21:00 hours to 03:00 hours. Sites and vehicles were selected randomly. Surveyors obtained information on several demographic and situational variables including self-assessed degree of sleepiness and self-reported hours asleep and awake, as well as an objective measure of blood alcohol concentration obtained from a hand-held breath-testing device. RESULTS: The total compliance rate among intercepted drivers was 85%. Among the 2335 drivers responding to the questionnaire, 68.4% indicated that they were wide awake, 27.6% were somewhat sleepy, and 4.1% were very sleepy. Logistic regression quantified the independent contributions of the various factors to subjective sleepiness. Male drivers with positive blood alcohol concentrations under 50 mg% were more likely to report feeling sleepy than those with either higher or with zero blood alcohol concentration. Greater relative risk of sleepiness was also associated with being female, being under age 55, and advanced hour of night. Driving with passengers of the same gender was associated with lower reported sleepiness. CONCLUSIONS: A substantial proportion of night-time drivers are driving while sleepy, especially at late night and early morning hours. The combination of alcohol and sleepiness compounds impairment in experimental studies and deserves greater attention in crash risk studies and as a topic for public education and awareness.  相似文献   
142.
Regional Environmental Change - This article addresses energy flows in the coffee agro-ecosystems of Costa Rica within the context of the socio-ecological transition, between 1935 and 2010,...  相似文献   
143.
Attempts to better understand the social context in which conservation and environmental decisions are made has led to increased interest in human social networks. To improve the use of social-network analysis in conservation, we reviewed recent studies in the literature in which such methods were applied. In our review, we looked for problems in research design and analysis that limit the utility of network analysis. Nineteen of 55 articles published from January 2016 to June 2019 exhibited at least 1 of the following problems: application of analytical methods inadequate or sensitive to incomplete network data; application of statistical approaches that ignore dependency in the network; or lack of connection between the theoretical base, research question, and choice of analytical techniques. By drawing attention to these specific areas of concern and highlighting research frontiers and challenges, including causality, network dynamics, and new approaches, we responded to calls for increasing the rigorous application of social science in conservation.  相似文献   
144.
Environmental and Ecological Statistics - This paper illustrates the use of diffusion kernels to estimate smooth density and regression functions defined on highly complex domains. We generalize...  相似文献   
145.
There is limited knowledge of the mechanisms that can inspire people's concern and engagement in the protection of unpopular and unappealing species. We analyzed Polish people's interest in themed internet memes featuring the proboscis monkey (Nasalis larvatus) and the consequences of this interest for conservation marketing. We examined Google Trends data, used Google Search, and searched popular media materials to estimate interest in the proboscis monkey in Poland. Photos of the proboscis monkey when presented with humor in internet memes attracted as much interest as usually more popular species (e.g., koala, panda, and orangutan) used in marketing by nongovernmental organizations. Amusing internet memes spread by social media positively correlated with increasing interest in the unappealing species, such as proboscis monkey. Interest in amusing internet memes positively correlated with individuals’ decisions to donate to 6 crowdfunding actions. Thus, conservation marketing that includes amusing memes and social media may provide a worthwhile complement to traditional campaigns and are likely to influence individuals who are unaffected by the usual means.  相似文献   
146.
Electronic tags (both biotelemetry and biologging platforms) have informed conservation and resource management policy and practice by providing vital information on the spatial ecology of animals and their environments. However, the extent of the contribution of biological sensors (within electronic tags) that measure an animal's state (e.g., heart rate, body temperature, and details of locomotion and energetics) is less clear. A literature review revealed that, despite a growing number of commercially available state sensor tags and enormous application potential for such devices in animal biology, there are relatively few examples of their application to conservation. Existing applications fell under 4 main themes: quantifying disturbance (e.g., ecotourism, vehicular and aircraft traffic), examining the effects of environmental change (e.g., climate change), understanding the consequences of habitat use and selection, and estimating energy expenditure. We also identified several other ways in which sensor tags could benefit conservation, such as determining the potential efficacy of management interventions. With increasing sensor diversity of commercially available platforms, less invasive attachment techniques, smaller device sizes, and more researchers embracing such technology, we suggest that biological sensor tags be considered a part of the necessary toolbox for conservation. This approach can measure (in real time) the state of free‐ranging animals and thus provide managers with objective, timely, relevant, and accurate data to inform policy and decision making.  相似文献   
147.
We adopt an interpersonal perspective and examine the adaptive effects of managers' perceived stress on their behavior towards subordinates. Drawing from the transactional model of stress (Lazarus & Folkman, 1984), we advance a model that highlights the propensity for stressed managers to engage in prosocial coping behaviors towards their employees, which in turn are related to lower levels of turnover and higher levels of job performance. We tested our predictions in a sample of 281 employees and their 53 managers working in a clothing retailer in Turkey. Consistent with predictions, we found positive effects of managers' perceived stress on their prosocial coping behaviors and employee outcomes. Managers' perceived stress was positively related to sharing credit with employees for managers who held positive implicit prototypes about employees. Results also indicated that managers' perceived stress was positively related to sharing knowledge with their subordinates regardless of implicit follower prototypes. Both sharing credit and sharing knowledge, in turn, were related to turnover intentions and actual turnover, and sharing credit was related to job performance. This study extends past work by adopting an interpersonal perspective of stress and demonstrating that managerial stress can have positive effects on employee outcomes via prosocial coping behaviors.  相似文献   
148.
The effects of oil dispersants BP10021, Finasol ESK and Corexit 7664 on the development of herring, Clupea harengus L., plaice, Pleuronectes platessa L. and sole, Solea solea (L.) have been studied. Treatment of developing embryos for 100 h with BP1002 and Finasol ESK gave rise to abnormalities in cell division and differentiation, to reductions in heart-rate, eye pigmentation, growth rate and hatching success above concentrations of 10 parts/106. Larvae with abnormal flexures of the spine, which prevented them from feeding successfully, resulted from exposure to 5 parts/106. Treatment of the embryos with dispersants throughout the period from fertilisation to hatching (15 to 20 days) produced similar abnormalities at slightly lower concentrations. Corexit did not produce any demonstrable deleterious effects on embryos exposed to concentrations up to 5000 parts/106, the highest tested.  相似文献   
149.
River floodplains have the potential to remove nitrate from water through denitrification, the anaerobic microbial conversion of nitrate to nitrogen gas. An important factor in this process is the interaction of river water with floodplain soil; however, many rivers have been disconnected from their historic floodplains by levees. To test the effect of reflooding a degraded floodplain on nitrate removal, we studied changes in soil denitrification rates on the Baraboo River floodplain in Wisconsin, USA, as it underwent restoration. Prior to this study, the site had been leveed, drained, and farmed for more than 50 years. In late fall 2002, the field drainage system was removed, and a gate structure was installed to allow controlled flooding of this site with river water. Soil moisture was extremely variable among zones and months and reflected local weather. Soil organic matter was stable over the study period with differences occurring along the elevation gradient. High soil nitrate concentrations occurred in dry, relatively organic-poor soil samples and, conversely, all samples with high moisture soils characterized by low nitrate. We measured denitrification in static cores and potential denitrification in bulk samples amended with carbon and nitrogen, one year before and two years following the manipulation. Denitrification rates showed high temporal and spatial variability. Static core rates of individual sites ranged widely (from 0.00 to 16.7 microg N2O-N x [kg soil](-1) x h(-1), mean +/- SD = 1.10 +/- 3.02), and denitrification enzyme activity (DEA) rates were similar with a slightly higher mean (from 0.00 to 15.0 microg N2O-N x [kg soil](-1) x h(-1), 1.41 +/- 1.98). Denitrification was not well-correlated with soil nitrate, organic matter content, or moisture levels, the three parameters typically thought to control denitrification. Static core denitrification rates were not significantly different across years, and DEA rates decreased slightly the second year after restoration. These results demonstrate that restored agricultural soil has the potential for denitrification, but that floodplain restoration did not immediately improve this potential. Future floodplain restorations should be designed to test alternative methods of increasing denitrification.  相似文献   
150.
Summary The effect of inter-litter competition on pup survival was investigated in pairs of female rats (Rattus norvegicus) living and breeding in the same environment. If a female gave birth when a 0- to 14-day-old litter was already present in the environment, her pups had a very high chance of surviving, similar to the situation in which no other litter was present. Moreover, the mother was likely to nurse communally with the mother of the 0- to 14-day-old litter. This communal nursing benefitted the newborn pups as evidenced by their being heavier at weaning than litters that were not nursed communally. In contrast, if a female gave birth when a 15-to 28-day-old litter was already present in the environment, her newborn pups were likely to die within 3 days postpartum, owing to the fact that they were often prevented from suckling at their mother's teats, resulting in milk deprivation, and were often beneath the older pups, resulting in physical trauma. These findings suggest that inter-litter competition is an important source of pup mortality when litters are born 15-28 days apart. The data are discussed in terms of the advantages of birth synchrony.  相似文献   
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