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211.
Problem: To assess how drivers view dangers on the highway, what motivates them to drive safely, how they say they reduce their crash and injury risk, and how they rate their own driving skills. Results: Most drivers rated their skills as better than average. The biggest motivating factor for safe driving was concern for safety of others in their vehicle, followed by negative outcomes such as being in a crash, increased insurance costs, and fines. The greatest threats to their safety were thought to be other drivers' actions that increase crash risk such as alcohol impairment or running red lights. In terms of reducing crashes and injuries, drivers tended to focus on actions they could take such as driving defensively or using seat belts. There was less recognition of the role of vehicles and vehicle features in crash or injury prevention. Impact on research, practice, and policy: Knowing how drivers view themselves and others, their concerns, and their motivations and techniques for staying out of trouble on the roads provides insight into the difficulty of changing driving practices.  相似文献   
212.
PROBLEM: To determine patterns of risk among teenage drivers. METHOD: Review and synthesis of the literature. RESULTS: On most measures, crash rates during the teenage years are higher than at any other age, for both males and females. Risk among teenagers varies greatly by driving situation; it is particularly low in some situations (e.g., the learner period) and particularly high in others (e.g., right after licensure, late at night, with passengers present). In some of these high-risk driving situations, risk is elevated for drivers of all ages (e.g., late night driving), in others risk is elevated more for teens than adults (e.g., driving after consuming alcohol), and in others the risk is unique to teen drivers (e.g., having passengers). IMPACT ON RESEARCH, PRACTICE, AND POLICY: These varying patterns of risk form the basis for graduated licensing systems, which are designed to promote low-risk and discourage high-risk driving.  相似文献   
213.
PROBLEM: A prior study indicated that zero tolerance laws differ in their enforceability and likelihood of enforcement, with California's law being easier to enforce than New York's, and New Mexico's being the hardest of all. The question is, do these differences in enforcement affect teenagers' knowledge and perception of these laws? METHOD: A telephone survey was conducted to investigate awareness of the laws among 17-20 year olds in these three states and perceptions of enforcement. RESULTS: Estimated percentages of teenagers who knew of the laws were much higher in New York and California (71% and 65%, respectively) than in New Mexico (34%). Perceptions that police were enforcing the law, that licenses could be suspended, and that penalties were often applied were also lowest in New Mexico. IMPACT ON INDUSTRY: The potential of zero tolerance laws will not be realized without better awareness among young people. Full enforcement of the laws accompanied by publicity about the enforcement is recommended. Changes to the laws and their application may encourage enforcement efforts.  相似文献   
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215.
We present two cases of abdominal pregnancy identified in our maternal serum screening programme—an additional, as yet unreported benefit of AFP+ (multiple analyte) maternal serum oncofetal antigen screening in pregnancy.  相似文献   
216.
Book reviews     
Green Culture: environmental rhetoric in contemporary America. C. G. Herndl & S. C. Brown (Eds), 1996, Madison, WI, University of Wisconsin Press, 315 pp. ISBN 0 229 14990 0, £35.95 (hbk) ISBN 0 299 14994 3, £17.50 (pbk)

Earthtalk: communication empowerment for environmental action. S. A. Muir & T. L. Veenendall, 1996, Westport, CT, Praeger, Praeger Series in Political Communication, 233 pp. ISBN 0 275 953700 X, £47.95

Environmentalism and Cultural Theory. Kay Milton, 1996 London & New York, Routledge, 266 pp. ISBN 0 415 115529 9, £45.00 (hbk) ISBN 0 415 11530 2, £13.99 (pbk)

Local Environmental Struggles: citizen activism in the treadmill of production. Kenneth A. Gould, Allan Schnaiberg & Adam S. Weinberg, 1996, Cambridge University Press, 239 pp. ISBN 0 521 55519 1, £40.00 (hbk) ISBN 0 521 55521 3, £14.95 (pbk)

The Language of Environment: a new rhetoric. George Myerson & Yvonne Rydin, 1996 London, UCL Press, 264 pp. ISBN 1 85728 330 9, £35.00 (hbk) ISBN 1 85728 331 7, £11.95 (pbk)

Environmental Issues and Business: implications of a changing agenda. Sally Eden, 1996, Chichester, Wiley, ISBN 0 471 94872 1, £25.00

Green Shift: towards a green sensibility in architecture. John Farmer, edited by Kenneth Richardson, 1996, Oxford, Butterworth Architecture, with World-Wide Fund for Nature, ISBN 07506 15303

Lewis Mumford and the Ecological Region: the politics of planning. Mark Luccarelli, 1995, New York, Guilford Press, ISBN 1572300019, £19.95

The Ecology of Hope: communities collaborate for sustainability. Ted Bernard & Jora Young, 1997, East Haven, CT, New Society Publishers, 233 pp. ISBN 0 86571 355 33 (pbk)

Turning the Tide: integrated local area management for Australia's coastal zone. Valerie A. Brown, 1995, Canberra, Australia, Department of the Environment, Sport and Territories

Involving Communities in Forestry through Community Participation. Forestry Practice Guide 10, Forestry Commission

The Scope for Community Participation in Forest Management. A Report for the Forestry Commission and Scottish Office by Bill Slee, Gill Clark & Patrick Snowdon, £10 (£15 non UK)

The Role of Woodlands in Meeting Planning Objectives in Great Britain. A Report for the Forestry Commission by Professor Paul Selman  相似文献   
217.
Using specially designed temperature profiling equipment, two surveys were conducted during thermal backwashing operations at Pilgrim Nuclear Power Station to determine the spatial and temporal extent of temperature rises above ambient. Thermal backwashing is a process where biofouling is combated by a heat treatment procedure. Backwashing formed a thermal plume about 5- to 6-ft thick (1.5- to 1.8-m) in front of the intake screenwall. Maximum observed surface temperatures were 101.0°F (38.3°C), representing a rise (T) of about 43.4°F (24.1°C) above ambient. The frontal zone of the plume spread gradually seaward at about 0.2 kn. Its outer edge became thinner and rapidly cooled, presumably by advection and turbulent diffusion associated with currents from the reverse pumping and local changes from dissipation to the atmosphere. Along the intake shoreline, the plume was often less than 1 ft (0.3 m) thick. Most of the hot water was dissipated within several hundred feet of the intake with Ts of about 10.0 to 15.0°F (5.6 to 8.3°C) above ambient. Under the influence of 15 mph southwesterly winds during the second survey, some warmed water was apparently carried beyond the outer breakwaters into Cape Cod Bay. These surveys provided real-time data indicating that the backwashing operation caused a relatively thin thermal plume, which spread rapidly from the intake out across the study area and along the seaward breakwater. Within a few hours these backwash thermal plumes were completely dissipated.Formerly affiliated with Normandeau Associates, Inc., Bedford, New Hampshire.  相似文献   
218.
Isozyme, randomly amplified polymorphic DNA, and ribosomal DNA analyses were used to evaluate the genetic distinctness and diversity of the endangered island endemic Malacothamnus fasciculatus var. nesioticus (Santa Cruz Island bush mallow). Analysis of amplified DNA profiles and electrophoretic data indicates that var. nesioticus is genetically distinct from other varieties within the species. No isozyme or amplified DNA variation was detected among individuals of nesioticus populations, but restriction site analysis of ribosomal DNA revealed the presence of three closely related genotypes within one of the nesioticus populations. Apparent clonal structuring was found in both nesioticus populations and in one mainland population, var. nuttallli . Results from these analyses provide the background necessary for the design of conservation efforts with recovery goals that insure the long-term survival of Malacothamnus fasciculatus var. nesioticus .  相似文献   
219.
Summary The behaviour of five adult wheatears (Oe. oenanthe) delivering prey (maggots and mealworms) from artificial patches to the nestlings was studied. The existence of a so-called loading effect was confirmed. Handling times for subsequent prey items increased with the number held in the beak, which led to a decrease in collecting rates with patch time and, in most cases, to positively accelerating loading functions when collecting times for prey items are plotted as a function of load size. All birds seemed to become more efficient at loading prey in the experimental patches during the course of the nestling period. Loading functions for maggots and mealworms were slightly different. When forcing the birds to visit several cups (only one item in each cup) and remove a layer of moss before reaching the prey (low-density patches), all birds took fewer prey and two of them stayed longer in them than in highdensity patches (one cup filled with prey items). This was due to an increase in search times with the number of prey held in the beak.From knowledge of the loading functions and travel times to the nest, it is possible to predict the optimal load sizes according to a mathematical solution of the delivery rate model of Orians and Pearson (1979). By transforming collecting and travel times to energy expenditures, it is also possible to derive predictions from an energy efficiency model (maximizing energy delivery per unit energy expended in a round-trip). The observed average load sizes did not differ significantly from those predicted by the delivery rate model, but they were significantly smaller in all cases than those predicted by the energy efficiency model. For birds feeding nestlings, it may be more important to sacrifice efficiency in energy expenditure in favour of greater delivery rates, thereby maximizing the growth rate of the young.  相似文献   
220.
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