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OBJECTIVE: The present study investigated the extent to which drinking in specific locations and heavy drinking mediated the effects of overall alcohol use on driving after drinking (DD) and riding with drinking drivers (RWDD) among young people. Additionally, this study examined the relationships among ethnicity, gender, drinking in specific locations, and DD and RWDD. METHOD: Using random-digit dialing procedures, participants were recruited to take part in a telephone survey in California, United States of America. Participants were 1,534 youth, ages 15-20 years (mean age = 17.6). Latinos, African Americans, and Asian Americans were over-sampled to allow cross-group comparisons. Along with background characteristics, overall alcohol use, heavy drinking, drinking in specific locations, DD, and RWDD were measured. RESULTS: Latent variable structural equation modeling showed that European Americans, males, older adolescents, those who have a driver license, and those who drive more often were more likely to report drinking alcohol in the past year. Heavy episodic drinking and drinking in cars increased both DD and RWDD. Drinking in restaurants also increased DD. The effects of overall alcohol consumption on DD were entirely mediated through heavy episodic drinking and drinking in restaurants and cars. Alcohol consumption had both direct and indirect effects on RWDD. With the exception of being Latino and frequency of driving, the effects of the background variables on RWDD were all entirely mediated through alcohol consumption. CONCLUSIONS: Heavy drinking and drinking in specific locations appeared to be important unique predictors of both DD and RWDD. In light of the relationship between drinking in restaurants and in cars, and DD, prevention programs and policies aimed at underage drinking should focus on developing more effective responsible beverage service programs, increasing compliance with laws limiting alcohol sales to youth, and enforcing graduated driver licensing and zero tolerance laws. 相似文献
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A. J. M. Walker 《Marine Biology》1972,14(1):85-87
Polychaetes of the genus Goniadella
Hartman were found in Liverpool Bay, England, in sand and sandy gravel below depths of 15 m. The worms had most of the characteristics of G. gracilis (Verrill), a species previously recorded only from eastern North America and South Africa. 相似文献
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In late 2003 the Feinstein International Famine Center, in partnership with institutions in London, Geneva and Washington, organised a series of consultations on the future of humanitarian action post-Iraq. This article is based on those discussions. A number of recurring concerns are elaborated, ranging from the perception of humanitarianism as a Northern-driven and Northern-controlled enterprise, through the politicisation of security and the devaluation of the protective power of emblems, to the very nature of how the crisis in Iraq is perceived. The article explores the implications of such issues for humanitarian workers and their institutions. It concludes by framing an agenda for action by the humanitarian sector. 相似文献
108.
Using mussels as monitoring tools we measured water quality in Sydney Harbour during a large scale, multi-year remediation project of the Sydney Tar Ponds (STPs); one of Canada's most contaminated sites. Chemical contaminants were measured in blue mussels (Mytilus edulis) in Sydney Harbour, which were used as monitoring tools to assess the spatio-temporal distribution of polycyclic aromatic hydrocarbons (PAHs); polychlorinated biphenyls (PCBs); metals (As, Cd, Cu, Hg, Pb, Zn) and lipid content during baseline and 3 years of remediation. The overall spatio-temporal distribution of chemicals in mussels was also compared to contaminants in other marine indicators (e.g., sediment, water and crab tissue). Measured metal concentrations in mussels showed some minor temporal variability (4 years), but these did not appear to be directly related to remediation activities, with the highest concentrations of As, Hg and Zn measured at reference stations. Most measured contaminants showed stable or potentially decreasing concentrations during the study, except Pb and Zn. Individual PAH compounds were mostly undetected during baseline and remediation, except for fluoranthene and pyrene. Concentrations of fluoranthene in mussels and deep water samples were moderately related. Generally, PCBs were undetected (<0.05 μg g?1), except during year 2 remediation at some near-field stations. Contaminants measured during this study were at much lower concentrations than previously reported in other studies of mussels in Sydney Harbour and eastern Canada. This is likely due to the ongoing natural recovery of Sydney Harbour and to a lesser extent because of the environmental mitigation protection measures implemented during remediation activities at the STPs. The lack of detection of most individual PAHs and PCBs, plus relatively low bio-accumulation of metals observed during baseline and remediation attest to the effectiveness of using mussels as monitoring tools for environmental quality. 相似文献
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Definition of an airworthiness certification framework for civil unmanned aircraft systems 总被引:1,自引:0,他引:1
Reece A. Clothier Jennifer L. Palmer Rodney A. Walker Neale L. Fulton 《Safety Science》2011,49(6):871-885
The development of effective safety regulations for unmanned aircraft systems (UAS) is an issue of paramount concern for industry. The development of this framework is a prerequisite for greater UAS access to civil airspace and, subsequently, the continued growth of the UAS industry. The direct use of the existing conventionally piloted aircraft (CPA) airworthiness certification framework for the regulation of UAS has a number of limitations. The objective of this paper is to present one possible approach for the structuring of airworthiness regulations for civilian UAS. The proposed approach facilitates a more systematic, objective and justifiable method for managing the spectrum of risk associated with the diversity of UAS and their potential operations. A risk matrix is used to guide the development of an airworthiness certification matrix (ACM). The ACM provides a structured categorisation that facilitates the future tailoring of regulations proportionate to the levels of risk associated with the operation of the UAS. As a result, an objective and traceable link may be established between mandated regulations and the overarching objective for an equivalent level of safety to CPA. The ACM also facilitates the systematic consideration of a range of technical and operational mitigation strategies. For these reasons, the ACM is proposed as a suitable method for the structuring of an airworthiness certification framework for civil or commercially operated UAS (i.e., the UAS equivalent in function to the Part 21 regulations for civil CPA) and for the further structuring of requirements on the operation of UAS in un-segregated airspace. 相似文献
110.
Ragosta G Evensen C Atwill ER Walker M Ticktin T Asquith A Tate KW 《Journal of environmental management》2011,92(8):1910-1915
Associations were examined between riparian canopy cover, presence of cattle near streams, and month of year with the concentration of Enterococcus (Most Probable Number (MPN)/100 ml) in surface water at Waipā watershed on the North Side of the Hawaiian island Kaua'i. Each one percent decrease in riparian canopy cover was associated with a 3.6 MPN/100 ml increase of waterborne Enterococcus. Presence of cattle near monitoring sites was associated with an increase of 99.3 MPN/100 ml of Enterococcus in individual grab samples. Lastly, summer samples (July) were substantially higher in concentration of Enterococcus than winter collected samples (February) in Enterococcus in sampled streams. These results suggest that reducing canopy cover and introduction of cattle into riparian zones may contribute to increases of Enterococcus concentrations in stream water. 相似文献