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881.
Petroleum exploration and production in the Barents Sea is a controversial topic. The Goliat field outside the northern coast of Norway will be the first offshore oil development in this region, with planned production start in 2013–2014. Avoiding major accidents at Goliat is critical; not only to reduce the risks to human lives and the environment, but also to gain political acceptance. Providing early warnings of major accidents for Goliat is one of the main objectives of the research project ‘Building Safety’. The objective of this paper is to describe the development of early warnings in the form of indicators. In addition, the paper includes an overview of current status of early warnings of accidents in other major hazard industries; the nuclear power industry, the chemical process industry, and aviation. Experiences from these industries, including lessons learned from recent major accidents, have been used as important input to the development of early warning indicators.  相似文献   
882.
INTRODUCTION: The study reported here was designed to test the ability of the theory of planned behavior to mediate the effect of parental supervision on adolescents' intentions to violate driving rules. METHOD: A representative sample of 1,654 adolescents completed questionnaires during individual and anonymous interviews carried out at their schools. RESULTS: Results showed that age, gender, prior risky driving-behavior, and parental supervision significantly predict intentions to violate driving rules. Attitude and the subjective norm partially mediate the effect of age, prior behavior, and parental supervision. Perceived behavioral control does not predict intention and is not predicted by other variables. IMPACT: The results suggest that social cognitive variables partially mediate the effect of parenting practices such as supervision.  相似文献   
883.
The U.S. Environmental Protection Agency's National Exposure Research Laboratory is pursuing a project to improve the methodology for modeling human exposure to motor vehicle emissions. The overall project goal is to develop improved methods for modeling the source through the air pathway to human exposure in significant exposure microenvironments. Current particulate matter (PM) emission models, particle emission factor model (used in the United States, except California) and motor vehicle emission factor model (used in California only), are suitable only for county-scale modeling and emission inventories. There is a need to develop a site-specific real-time emission factor model for PM emissions to support human exposure studies near roadways. A microscale emission factor model for predicting site-specific real-time motor vehicle PM (MicroFacPM) emissions for total suspended PM, PM less than 10 microm aerodynamic diameter, and PM less than 2.5 microm aerodynamic diameter has been developed. The algorithm used to calculate emission factors in MicroFacPM is disaggregated, and emission factors are calculated from a real-time fleet, rather than from a fleet-wide average estimated by a vehicle-miles-traveled weighting of the emission factors for different vehicle classes. MicroFacPM requires input information necessary to characterize the site-specific real-time fleet being modeled. Other variables required include average vehicle speed, time and day of the year, ambient temperature, and relative humidity.  相似文献   
884.
The wild mink has gained acceptance as a sentinel species in environmental monitoring. However, only limited data are available in the literature on factors driving variability in concentrations of organic pollutants in this species. This study characterizes the differences in contaminant concentrations in subcutaneous fat of male mink from four different areas in Sweden and demonstrates how age, season and body condition influence concentrations of polychlorinated biphenyl (PCB) congeners, polybrominated diphenyl ether (PBDE) congeners (including methoxylated forms, MeO-PBDEs), as well as the pesticides dichlorodiphenyldichloroethylene (DDE), chlordane and hexachlorobenzene (HCB). The data were statistically treated using multiple regression and principal component analysis. The ∑PCB concentration and concentrations of PCB congeners 138, 156, 157, 180, 170/190, 189, 194, 206, 209 as well as PBDE 153/154 varied with age. Season had an influence on ∑PCB, PBDE 47 and PBDE 153/154 concentrations, as well as concentrations of most PCB congeners, with the exception of PCB 101, 110, 141 and 182/187. Lean mink had higher concentrations of most PCBs and PBDEs than mink with larger fat depots. The analyzed pesticides (DDE, oxychlordane, HCB) showed no systematic variation with season, age or body condition. The concentrations of MeO-PBDEs were generally low and 6MeO-PBDE 47 was the most commonly detected MeO-PBDE in mink from marine, brackish and freshwater areas. The results indicate that age, season and body condition are factors that may influence the concentrations of PCBs and PBDEs, and it is thus recommended to take these factors into account when analyzing mink exposure data.  相似文献   
885.
A “finding of no significant impact” (FONSI) resulting from an environmental assessment (EA) was reported by the US Army in June 1986 for the construction and utilization of a multipurpose range complex (MPRC) at the Pohakuloa Training Area, Hawaii. There was little public response, and the US Fish and Wildlife Service and state agencies were consulted and had few comments concerning the results of the botanical surveys used in the assessment. Construction of the $24 million project was begun in 1988. Near the end of construction in 1989 a lawsuit was filed to halt construction because an environmental impact statement (EIS) had not been done for the project, and the plaintiff thought that significant damage had occurred to several unusual ecosystems. Judgment was against the plaintiff and construction continued. An appeal was filed with the 9th Circuit Court. As MPRC construction was nearly complete, and on advice of Department of Justice lawyers, the Department of Army agreed to settle out of court. The settlement in part called for: (1) the plaintiff to drop the appeal and allow construction to be completed as scheduled, and (2) the Department of Army to prepare an EIS for the operation of the MPRC. A subsequent botanical survey for the EIS discovered one endangered plant species, four category 1 candidate plant species (taxa with sufficient data to support listing as endangered or threatened), three category 2 candidate plant species (taxa with some evidence of vulnerability but insufficient data to support listing at this time), one category 3a species (presumably extinct taxa), and possibly three undescribed species growing within the MPRC boundary. The MPRC case study is an excellent example of why the National Environmental Policy Act (NEPA) must be modified to require in-depth and thorough environmental surveys.  相似文献   
886.
887.
Samples of the population of Yoldia limatula Say were obtained from the Bideford River, Malpeque Bay, Prince Edward Island, Canada, during the summers of 1979 and 1980 by means of a dredge and a Ponar grab sampler. Size frequency analysis demonstrated that individuals in the size range 25- to 35-mm shell length were numerically dominant in May, June and July. Recruitment of juveniles in August resulted in the dominance of individuals of 5 mm and smaller which comprised 50% of the population at that time. The overall sex ratio was 48.8% males to 51.2% females. From annual lengths measured at successive winter growth bands it was determined that one-yr olds attained a shell length of between 13.8 and 17.7 mm, two-yr olds between 26.7 and 28.0 mm, three-yr olds between 33.8 and 35.2 mm, and foru-yr olds had a mean length of 38.7 mm. Y. limatula produced a croppable annual yield of between 1.19 and 2.65 g dry tissue weight m-2 with P/B ratios of 0.65 and 1.45 respectively.  相似文献   
888.
Lead, cadmium and zinc concentrations have been obtained in a total of 83 soil and dust samples in and around the city of Cuenca, Ecuador. Elevated heavy metal concentrations were observed in the city, with comparable Pb concentrations to those commonly found in European and North American cities. Lead concentrations were also elevated above the estimated regional background (less than 9 microg g(-1)) along a rural track used by about 100 vehicles per day. The extent of the contamination by Cd and Zn was restricted to the urban area.  相似文献   
889.
890.
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