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301.
This report summarizes evidence presented during the Third Annual Ignition Interlock Symposium at Vero Beach, Florida, 29 October 2002. The ignition interlock prevents a car from starting when blood alcohol concentration (BAC) is elevated. We review some of our prior work as well as introduce previously unpublished results to demonstrate the manner in which the data recorded by the alcohol ignition interlock device can serve as an advance predictor of future driving under the influence (DUI) of alcohol risks. Data used in this current report represent approximately 2,200 ignition interlock users from Alberta, Canada, and about 8,000 interlock users from Quebec, Canada; the Alberta data set contained 5.5 million breath tests and the Quebec data 18.8 million breath tests. All tests are time and date stamped and this information was used to characterize patterns of BAC and vehicle use, and the relationship between BAC elevations and DUI offenses that accumulated after the interlock was removed from the vehicles. Findings from Cox regression show that BAC elevations >.02-.04% are more potent predictors of repeat DUI (p<.0001) than even prior DUI (p<.006), usually found to be the strongest indicator of driver risk. Prior DUI obviously has no use for scaling the risk of first-time offenders. Drivers who are both multiple offenders and who have more than a few elevated interlock BAC tests are much more likely to repeat DUI. The timing and pattern of elevated BAC tests provided during the time drivers were required to use an alcohol ignition interlock device are remarkably similar on both a daily basis and an hourly basis when the interlock programs from the two provinces are compared directly. Both provinces had higher rates of elevated tests on Saturday and Sunday, and the fewest elevated tests on Tuesdays. The absolute rate of elevated tests is similar despite the two provinces adhering to different interlock lockout points (.02% Quebec;.04% Alberta). Charts tracking the Monday-Friday timing of elevated BAC tests by hour are nearly identical for both provinces. The most elevated BAC tests occurred between 7 and 9 A.M. Monday to Friday, even though most vehicle start attempts occurred much later in the day. This higher rate of elevated morning BAC likely represents drinking from the prior evening with alcohol not yet cleared from circulation; those with elevated BAC in the early morning were more likely to have a repeat offense even after accounting for prior DUI and the higher overall rate of elevated BAC tests. This is viewed as evidence of a drinking problem that will lead to impaired driving after the controlling function of the interlock is removed. Policy changes are discussed that might take better advantage of interlock information to improve the public response to drunk driving.  相似文献   
302.
Problem. Researchers agree that a consistent definition for aggressive driving is lacking. Such definitional ambiguity in the literature impedes the accumulation of accurate and precise information, and prevents researchers from communicating clearly about findings and implications for future research directions. This dramatically slows progress in understanding the causes and maintenance factors of aggressive driving. Summary. This article critiques prevailing definitions of driver aggression and generates a definition that, if used consistently, can improve the utility of future research. Pertinent driving behaviors have been variably labeled in the literature as risky, aggressive, or road rage. The authors suggest that the term “road rage” be eliminated from research because it has been used inconsistently and has little probability of being clarified and applied consistently. Instead, driving behaviors that endanger or have the potential to endanger others should be considered as lying on a behavioral spectrum of dangerous driving. Three dimensions of dangerous driving are delineated: (a) intentional acts of aggression toward others, (b) negative emotions experienced while driving, and (c) risk-taking. Impact on Industry. The adoption of a standardized definition for aggressive driving should spark researchers to use more explicit operational definitions that are consistent with theoretical foundations. The use of consistent and unambiguous operational definitions will increase the precision of measurement in research and enhance authors' ability to communicate clearly about findings and conclusions. As this occurs over time, industry will reap benefits from more carefully conducted research. Such benefits may include the development of more valid and reliable means of selecting safe professional drivers, conducting accurate risk assessments, and creating preventative and remedial dangerous driving safety programs.  相似文献   
303.
Geography inherently fills a 3D space and yet we struggle with displaying geography using, primarily, 2D display devices. Virtual environments offer a more realistically-dimensioned display space and this is being realized in the expanding area of research on 3D Geographic Information Systems (GISs). Traditionally, a GIS has only limited tools for statistical analysis, and 3D GIS research has concentrated on the visualization of the geographical terrain. Here we discuss linking multivariate statistical graphics to geography in the highly immersive C2 virtual reality environment at Iowa State University using mid-Atlantic streams data.  相似文献   
304.
/ The US Environmental Protection Agency's Wetlands ResearchProgram has developed the synoptic approach as a proposed method forassessing cumulative impacts to wetlands by providing both a general and acomprehensive view of the environment. It can also be applied more broadly toregional prioritization of environmental issues. The synoptic approach is aframework for making comparisons between landscape subunits, such aswatersheds, ecoregions, or counties, thereby allowing cumulative impacts tobe considered in management decisions. Because there is a lack of tools thatcan be used to address cumulative impacts within regulatory constraints, thesynoptic approach was designed as a method that could make use of availableinformation and best professional judgement. Thus, the approach is acompromise between the need for rigorous results and the need for timelyinformation. It is appropriate for decision making when quantitative,accurate information is not available; the cost of improving existinginformation or obtaining better information is high; the cost of a wronganswer is low; there is a high demand for the information; and the situationcalls for setting priorities between multiple decisions versus optimizing fora single decision. The synoptic approach should be useful for resourcemanagers because an assessment is timely; it can be completed within one totwo years at relatively low cost, tested, and improved over time. Anassessment can also be customized to specific needs, and the results arepresented in mapped format. However, the utility of a synoptic assessmentdepends on how well knowledge of the environment is incorporated into theassessment, relevant to particular management questions.KEY WORDS: Cumulative impact assessment; Landscape ecology; Regionalprioritization  相似文献   
305.
Using a comprehensive approach to decommission a 180,000-square-foot automotive parts manufacturing facility saves time and money while reducing environmental liability. Prior to starting the facility decommissioning, a detailed facility characterization was conducted to identify contaminated areas. Remediation activities were scheduled to coincide with facility demolition. Specialized subcontractors were used to perform tasks such as asbestos and lead-paint abatement, soil bioremediation, underground storage tank and clarifier removal, and facility destruction and recycling. The project timetable was reduced by using several crews simultaneously to conduct recycling, demolition, and remediation. Costs were offset by selling remaining equipment, scrap metals, overhead lights and fixtures, and a premanufactured steel building. A total of 415 tons of scrap metal was recycled, not including the aforementioned steel building. On-site recycling and remediation were used wherever possible to reduce cost and associated hauling liabilities. For example, concrete and asphalt debris were crushed and used as base for final site paving, saving disposal costs and base material purchase costs. On-site bioremediation of soil impacted by perchloroethene (PCE) saved over $1.5 million, with total project savings of $2.4 million. On-site remediation and recycling also reduced both long-term and short-term environmental liability.  相似文献   
306.
Using ecological criteria to evaluate wilderness planning options in Idaho   总被引:1,自引:0,他引:1  
Legally designated wilderness areas are acknowledged to be an important element in strategies to conserve biological diversity in United States. However, because of the restrictions on consumptive uses in wilderness, their establishment is normally contentious. Criteria for establishment have typically been associated with opportunity and aesthetic and experiential values. Biological data have not normally played a major role in guiding wilderness establishment. We present four wilderness allocation options for those public lands considered suitable for wilderness designation in Idaho. These options cover the span of choices presently available to wilderness planners in the state and range from not establishing any new wilderness areas to the inclusion of all suitable lands in wilderness. All options are evaluated using spatial biological data from the National Biological Survey's Gap Analysis Project. A conservation strategy that would protect a minimum of 10% of the area occupied by each of 113 native vegetation types and at a minimum 10% of the distribution of each of 368 vertebrate species was evaluated for each option. Only the inclusion of all suitable lands in wilderness, creating a system of 5.1 million ha came close to achieving these goals, protecting 65% of the vegetation types and 56% of the vertebrate species. We feel this approach, which allows planners to evaluate the ecological merits of proposed widerness units along with other values, can provide a means to resolve the impasse over additional wilderness designation in Idaho.  相似文献   
307.
308.
Monitoring activities in protected areas have a long history. Internal planning and management needs early led to ecological inventories. More recently the increasing number and awareness of external threats to parks has led to a variety of monitoring programs. Efforts to use protected areas, and especially biosphere reserves, as ecological baselines, have reinforced this trend. And as protected areas are increasingly recognized to be islands with complex internal and regional interactions, holistic, systems approaches to inventory, monitoring, and assessment of their state are being developed. This paper begins by reviewing threats to parks and the origins and importance of inventory and monitoring activities. A review of resource survey methods follows. Ecosystem science and environmental monitoring are introduced as a foundation for consideration of several newer approaches to monitoring and assessing the state of natural environments. These newer approaches are stress/response frameworks, landscape ecology, ecosystem integrity, and state of the environment reporting. A final section presents some principles for monitoring the state of protected areas. Examples are drawn from experience with Canadian national parks.  相似文献   
309.
There are two issues in indicator development that have not been adequately addressed: (1) how to select an optimal combination of potentially redundant indicators that together best represent an endpoint, given cost constraints; (2) how to identify and evaluate indicators when the endpoint is unmeasured. This paper presents an approach to identifying and evaluating combinations of indicators when the mathematical relationships between the indicators and an endpoint may not be quantified, a limitation common to many ecological assessments. The approach uses the framework of Structural Equation Modeling (SEM), which combines path analysis withmeasurement models, to formalize available informationabout potential indicators and to evaluate their potential adequacy for representing an endpoint. Unlike traditional applications of SEM which require data on all variables, our approach – judgement-based SEM (JSEM) – can utilize expert judgement regarding the strengths and shapes of indicator-endpoint relationships. JSEM is applied in two stages. First, a conceptual model that relates variables in a network of direct and indirect linkages is developed, and is used to identify indicators relevant to an endpoint. Second, an index of indicator strength – i.e., the strength of the relationship between the endpoint and a set of indicators – is calculated from estimates of correlation between the modeled variables, and is used to compare alternative sets of indicators. The second stage is most appropriate for large, long-term assessments. Although JSEM is not a statistical technique, basing JSEM on SEM provides a structure for validating the conceptual model and for refining the index of indicator strength as data become available. Our main objective is to contribute to a rigorous and consistent selection of indicators even when knowledgeabout the ability of indicators to represent an endpoint is limited to expert judgement.  相似文献   
310.
This paper assesses the uptake of persistent organic pollutants (POP's) into plants. In particular, uptake of alpha-endosulfan, beta-endosulfan and endosulfan sulfate from lettuce. The lettuce plants were grown on compost that had previously been contaminated at 10 and 50 microg g(-1) per POP. The soil was slurry spiked by adding the appropriate amount of POP in acetone in an approximate ratio of 1 ratio 2, w/v soil ratio solvent. The solvent was left to evaporate at ambient temperature for 24 hours. Lettuce plants were grown under artificial daylight for 12 hours a day. The influence of soil ageing on the recovery of POP's from spiked soil samples was also assessed. The average recovery of endosulfan compounds from slurry spiked soil (10, 20 and 40 microg g(-1)) was consistent (92.9 +/- 4.4% for n= 9). However, ageing of endosulfan compounds on the slurry spiked soil resulted in lower recoveries (average losses were 12.5% after 14 days ageing of slurry spiked soil). The uptake of POP's was assessed by measuring the amount of endosulfan compounds in roots and leaves from lettuce plants after 10, 20 and 33 days. In addition, control plants grown in uncontaminated soil were monitored and analysed. It was found that endosulfan compounds were present in the roots of all lettuce plants irrespective of soil spike level or age of plant. In the 33 day lettuce plants where the soil was spiked at the highest level (50 microg g(-1)) endosulfan compounds were determined in the leaves. The root to leaf ratio was found to be 3.1 for alpha-endosulfan, 46.0 for beta-endosulfan, and 24.3 for endosulfan sulfate. Spiked lettuce samples were subjected to in vitro gastrointestinal extraction to assess the bioavailability of endosulfan compounds. No detectable endosulfan compounds were determined in the gastric extracts while small quantities (range 0.06-0.12 microg g(-1)) were found in the intestinal extraction. All samples (soil and lettuce) were extracted using pressurised fluid extraction and analysed using gas chromatography with mass selective detection.  相似文献   
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