Improving graduated driver licensing systems: a conceptual approach and its implications

Graduated driver licensing (GDL) is a concept for how to transform non-drivers into reasonably safe drivers while minimizing the risks as they learn. Several state GDL programs can be improved by moving their structures closer to an adequate implementation of that concept. The learner stage of a GDL system needs to be long enough for beginners to obtain a thorough introduction to the vagaries of driving. The second or intermediate stage needs to effectively limit exposure to known high risk conditions as novices adapt to being fully in charge of the vehicle. The benefits of GDL to date are due almost entirely to the risk-reducing conditions it implements. To improve the functioning of GDL will probably require a better understanding of teen driving than we presently have. The likelihood of further gains will be enhanced by efforts to learn more about the actual causes of teen crashes, the nature and type of teen driver exposures, and what parents do with their teens during the supervised driving stage of GDL. Without a better understanding of these, and other, phenomena it will be difficult to further reduce crashes among young beginning drivers, whether through GDL enhancements or with other approaches.     

Graduated driver licensing restrictions: awareness, compliance, and enforcement in North Carolina

PROBLEM: This study examined the extent to which critical restrictions in North Carolina's graduated driver licensing (GDL) system are known, adhered to, and enforced. METHOD: Teenagers and their parents were recruited as they applied for either an intermediate or full license at 1 of 23 licensing offices. Telephone interviews were conducted with 900 teenagers and their parents. RESULTS: Awareness of North Carolina's night and passenger restrictions was very high among both parents and teenagers. Ten percent of teenagers reported violating the night restriction without their parents' knowledge, and 15% had done so with their parents' approval. Only 4% of parents reported allowing their teenagers to drive with more than one teenage passenger, but 19% of teenagers reported that they were allowed to do this. Violations of the passenger restriction without parental knowledge were more common than violations of the night restriction (22% vs. 10%, respectively). Among teenagers who violated restrictions without their parents' knowledge, most reported doing so only once or a few times. Teenagers expressed little concern about detection, although a majority reported driving more carefully to avoid police notice. Neither parents nor teenagers knew much about police enforcement of GDL restrictions. To obtain a sense of the views of law enforcement officers, informal interviews were conducted with 20 officers from five diverse communities and the state highway patrol. These officers were highly supportive of GDL but unfamiliar with many of the specific provisions. Moreover, enforcement of GDL restrictions did not appear to be a high priority. IMPACT ON INDUSTRY: There is a need to increase the belief among teens (and parents) that police are enforcing GDL restrictions in their community; law enforcement participation in well-publicized traffic safety enforcement efforts would likely produce this result.     

Protective factors associated with young passenger intervening in risky driving situations

IntroductionWhile the negative influence of passengers on driving is usually studied, young passengers may protect against young drivers' crash involvement by speaking out and trying to stop unsafe driving behavior. This study sought to examine psychosocial constructs of young passengers who are likely to intervene in their friends' risky driving.MethodUniversity students aged 17 to 25 years who were single (n = 123) or in a romantic relationship (n = 130) completed an online survey measuring protective factors.ResultsThe combination of individual, friend and (for participants in a relationship) romantic partner protective factors predicted self-reported passenger intervening intentions.Impact on IndustrySince peer passengers often increase young drivers' crash risk, research on passenger intervening has significant implications for road safety strategies. The findings provide support for the operationalization of protective factors in strategies that target passenger intervening behavior.     

Hyperbenthic crustacean fauna of the Gullmarfjord area (western Sweden): Species richness,seasonal variation and long-term changes

Distribution of 118 species of Amphipoda, Mysidacea and Decapoda, sampled in 1984 and 1985 with an epibenthic sledge along a transect from the Skagerrak to the inner Gullmarfjord (Sweden), is described. Amphipods were richest in species in the Skagerrak, while most mysid species were taken at the sill. Deca-impoverished and the Lilljeborgidae, earlier represented by three species, had disappeared since the 1930s. The changes are most likely caused by eutrophication of the fjord. and deep-basin samples; (III) sill samples; (IV) Skagerrak samples. Characteristic species of the groups were identified with a pseudoF-test. Detrended Correspondence Analysis indicated seasonal faunal changes at 42 and 72 m depths. At both depths a shift in numerical dominance from amphipods to mysids was found in winter. The most pronounced changes seemed to occur at 42 m. Changes in composition and abundance of species during a renewal of the bottom water indicated that mysids were influenced by presumed near-bottom currents, while amphipods and decapods were not. Comparison of the present amphipod fauna with the fauna in 1933–37 revealed significant differences. The fauna in the deep basin was impoverished and the Lilljeborgidae, earlier represented by three species, had disappeared since the 1930s. The changes are most likely caused by eutrophication of the fjord.     

Corrigendum

Distribution of 118 species of Amphipoda, Mysidacea and Decapoda, sampled in 1984 and 1985 with an epibenthic sledge along a transect from the Skagerrak to the inner Gullmarfjord (Sweden), is described. Amphipods were richest in species in the Skagerrak, while most mysid species were taken at the sill. Decapods did not display any clear pattern. Twinspan, a multivariate data analysis program, divided the samples into four groups: (I) deep-fjord samples; (II) sill, shallow-fjord and deep-basin samples; (III) sill samples; (IV) Skagerrak samples. Characteristic species of the groups were identified with a pseudoF-test. Detrended Correspondence Analysis indicated seasonal faunal changes at 42 and 72 m depths. At both depths a shift in numerical dominance from amphipods to mysids was found in winter. The most pronounced changes seemed to occur at 42 m. Changes in composition and abundance of species during a renewal of the bottom water indicated that mysids were influenced by presumed near-bottom currents, while amphipods and decapods were not. Comparison of the present amphipod fauna with the fauna in 1933–37 revealed significant differences. The fauna in the deep basin was impoverished and the Lilljeborgidae, earlier represented by three species, had disappeared since the 1930s. The changes are most likely caused by eutrophication of the fjord.     

Encouraging compliance with graduated driver licensing restrictions

PROBLEM: Although graduated driver licensing (GDL) programs have reduced the high crash rates for 16-and 17-year-old drivers, research suggests that some teenagers fail to comply with restrictions on nighttime driving and carrying passengers. METHOD: A program to encourage compliance with GDL restrictions and seat belt requirements was implemented in Guilford County, North Carolina. The program combined increased enforcement with a multi-faceted publicity campaign drawing attention to the enforcement activity. A comparison community was studied to assess whether changes over time could be reasonably attributed to the program. RESULTS: Several measures indicate that greater enforcement did occur in the intervention community and that teenagers perceived the increase. However, self-reported data and direct observations of young drivers in the intervention and comparison communities showed the program resulted in only modest changes in compliance with GDL restrictions. DISCUSSION: The program put in place the mechanisms known to produce changes in driver behavior, but these may have been insufficient to alter the behavior of the minority of teenagers (and parents) who were not already complying with restrictions. However, the modest changes in young driver behavior plus the clear changes in both actual and perceived enforcement suggest that high visibility enforcement programs merit further use and evaluation in other communities, particularly those where compliance with GDL provisions is lower than in Guilford County.     

Norwegian Meteorological Institute’s real-time dispersion model snap (Severe Nuclear Accident Program): Runs for ETEX and ATMES II experiments with different meteorological input

The Norwegian Meteorological Institute (DNMI) has developed and implemented for operational use a real-time dispersion model Severe Nuclear Accident Program (SNAP) with capability for predicting concentrations and depositions of the radioactive debris from large accidental releases. SNAP has been closely linked to DNMI’s operational numerical weather prediction (NWP) models.How good are these predictions? Participation in ETEX has partly answered this question. DNMI used SNAP with LAM50S giving meteorological input for these real-time dispersion calculations. LAM50S Limited Area Model with 50 km grid squareswas DNMI’s operational NWP model in 1994 when ETEX took place.In this article we report on how SNAP performed in the first of the ETEX releases in near-real-time mode, using LAM50S—and in hindcast mode for ATMES II, using “ECMWF 1995: ETEX Data set (ATMES II)”as meteorological input data. These two input data sets came from NWP models with quite different characteristics but with similar resolution in time and space.The results from these dispersion simulations matched closely. Deviations early in the simulation period shrank to insignificant differences later on. Since both input data sets were based on “weather analysis” and had similar resolution in space and time, SNAP described the dispersion of the released material very similar in these two simulations.     

Effects of the polycyclic aromatic hydrocarbon fluoranthene on growth rate and nucleic acid composition of Capitella sp. I

Body volume growth rate, dry tissue weight, organic carbon content, and nucleic acid content (RNA and DNA) of individual Capitella sp. I were measured after 14 d of exposure to natural sediment, sediment contaminated with fluoranthene (in acetone) and sediment treated with acetone only. Exposure to 101 μg fluoranthene g⁻¹ sediment dry wt during 2 weeks reduced body volume specific growth rate by 50%. Dry tissue weight and carbon content were also lower in fluoranthene-exposed worms. However, when corrected for differences in body volume, worms from fluoranthene-contaminated sediment had a higher dry weight and carbon content per unit body volume than worms from the control and acetone treatments. Part, but not all, of the reduction in body volume growth rate in response to fluoranthene may have been due to a reduction in tissue water content. The correlation between RNA:DNA ratio (which has previously been used as a predictor of recent growth rate) and worm growth rate was weak in the control group and was significantly influenced by sediment treatment. Not only did the fluoranthene-exposed worms have a lower growth rate than expected based on their RNA:DNA ratio, but analysis of this group separately indicated that measured growth rate was independent of the RNA:DNA ratio. Our results not only confirm previous indications of a weak relationship between nucleic acid content and actual growth, but indicate that empirical, predictive relationships between these variables measured under favorable growth conditions should not be extrapolated to predict growth under toxicant-stressed conditions. Received: 6 April 1997 / Accepted: 7 May 1997