Self-reported seatbelt use,United States, 2002–2010: Does prevalence vary by state and type of seatbelt law?

ProblemMotor-vehicle crashes are a leading cause of death in the United States. Seatbelts are highly effective in preventing serious injury and death in the event of a crash. Not all states have primary enforcement of seatbelt laws.MethodsData from the 2002, 2006, 2008, and 2010 Behavioral Risk Factor Surveillance System were used to calculate prevalence of seatbelt use by state and type of state seatbelt law (primary vs. secondary enforcement).Results and discussionSelf-reported seatbelt use among adults in the United States increased steadily between 2002 and 2010, with the national prevalence reaching 87% in 2010. Overall, seatbelt use in 2010 was 9 percentage points higher in the states with primary enforcement laws than in the states with secondary enforcement laws (89% vs. 80%). Impact on industry: Primary enforcement seatbelt laws and enhanced enforcement of seatbelt laws are proven strategies for increasing seatbelt use and reducing traffic fatalities.     

Neurophysiological alterations due to diesel exhaust exposure during the neonatal life of the rat

This study was designed to assess the effects of diesel exhaust on the development of the nervous system in rats as measured by somatosensory and visual evoked potentials (SEPs and VEPs, respectively). SEPs, elicited by 1 mamp, 0.5 msec pulses delivered to the tibial nerve at the tibale, were recorded from the skull overlying the somatosensory projection area on days 28, 35, 42, and 49 postconception (pc). Analysis of the data for day 35 pc double pulse SEPs revealed significantly longer latencies for all peaks of the SEP in pups exposed to diesel exhaust. There were also differences indicating that the electrophysiological recoverability of the nervous system had been compromised in the diesel exhaust exposed group. On day 35 pc, the latencies of all VEP peaks occurring before 300 msec were greater in the exposed group. The differences, however, reached statistical significance only for the P2 peak of the response to the first of the paired stimuli. These data support the hypothesis that diesel exhaust influences the development of the nervous system.     

Age of licensure and monitoring teenagers' driving: survey of parents of novice teenage drivers

OBJECTIVE: To assess parental decision making regarding the timing of teenagers initiating driving and monitoring teenagers' driving after licensure. METHODS: About 300 parents were interviewed during spring 2006 in Minnesota, North Carolina, and Rhode Island, states with varying licensing provisions, while teenagers took their first on-road driving tests. RESULTS: States' differences in ages of obtaining learner's permits and licenses reflected different licensing laws, but most teenagers obtained permits and took road tests within the first few months after they became eligible. Common reasons for delaying obtaining permits were fulfilling driver education requirements and lack of readiness/immaturity. Insufficient practice driving most often delayed licensure. Among the parents interviewed, 33-49% believed the minimum licensure age should be 17 or older. Almost all parents planned to supervise teenagers' driving after licensure, and most wanted to know about speeding or distractions. When asked about in-vehicle devices to monitor teenagers' driving, 37-59% of parents had heard of them. Parents were least interested in using video cameras and about equally interested in computer chips and cell-phone-based GPS systems. Disinterest in monitoring devices most often was attributed to trusting teenagers or respecting their privacy. CONCLUSIONS: Licensing laws influence ages of initiating driving. Although many parents support licensing at 17 or older - higher than in all but one state - most teenagers initiate driving soon after reaching the minimum age. Parents plan to supervise teenagers' driving, and many say they are open to using in-vehicle monitoring devices. IMPACT ON INDUSTRY: Many parents support a minimum licensing age of 17 or older and would consider in-vehicle devices to extend their supervision of teenager's driving.     

Cooperative breeding in purple gallinules: the role of helpers in feeding chicks

Summary The participation of breeders and helpers in the feeding of 21 broods of chicks was studied in a population of cooperatively breeding purple gallinules (Porphyrula martinica). In the breeding group, all birds over the age of 2 months fed chicks. Female breeders fed chicks at the highest rate, followed by male breeders and adult helpers, old juvenile helpers, and young juvenile helpers. The amount of food breeders fed chicks was independent of the number of helpers in the breeding group. However, breeders made fewer feeding visits when they had helpers. Male and female breeders spent similar amounts of time feeding chicks. Helpers spent significantly less time feeding chicks than did breeders. As helpers grew older they fed chicks at a faster rate, made more feeding visits and spent more time feeding chicks. Analysis of variance was used to determine which variables explained the variation in the brood feeding rate (amount of food delivered to an entire brood during one observation). Age of chicks had a significant nonlinear effect, and size of brood and number of helpers had significant linear effects on the brood feeding rate. Chicks in groups with helpers received more food and were accompanied for longer periods of time than chicks in groups without helpers; either or both of these factors may have led to increased chick survival.     

Assessing nitrogen and phosphorus removal potential of five plant species in floating treatment wetlands receiving simulated nursery runoff

The feasibility of using floating treatment wetlands (FTWs) to treat runoff typical of commercial nurseries was investigated using two 8-week trials with replicated mesocosms. Plants were supported by Beemat rafts. Five monoculture treatments of Agrostis alba (red top), Canna × generalis ‘Firebird’ (canna lily), Carex stricta (tussock sedge), Iris ensata ‘Rising Sun’ (Japanese water iris), Panicum virgatum (switchgrass), two mixed species treatments, and an unplanted control were assessed. These plant species are used for ornamental, wetland, and biofuel purposes. Nitrogen (N) and phosphorus (P) removals were evaluated after a 7-day hydraulic retention time (HRT). N removal (sum of ammonium-N, nitrate-N, and nitrite-N) from FTW treatments ranged from 0.255 to 0.738 g·m^?2·d^?1 (38.9 to 82.4% removal) and 0.147 to 0.656 g·m^?2·d^?1 (12.9 to 59.6% removal) for trials 1 and 2, respectively. P removal (phosphate-P) ranged from 0.052 to 0.128 g·m^?2·d^?1 (26.1 to 64.7% removal) for trial 1, and 0.074 to 0.194 g·m^?2·d^?1 (26.8 to 63.2% removal) for trial 2. Panicum virgatum removed more N and P than any other FTW treatment and the control in both trials. Results show that species selection and timing of FTW harvest impact the rate and mass of nutrient remediation. FTWs can effectively remove N and P from runoff from commercial nurseries.

     

Characterizing source-sink dynamics with genetic parentage assignments

Source-sink dynamics have been suggested to characterize the population structure of many species, but the prevalence of source-sink systems in nature is uncertain because of inherent challenges in estimating migration rates among populations. Migration rates are often difficult to estimate directly with demographic methods, and indirect genetic methods are subject to a variety of assumptions that are difficult to meet or to apply to evolutionary timescales. Furthermore, such methods cannot be rigorously applied to high-gene-flow species. Here, we employ genetic parentage assignments in conjunction with demographic simulations to infer the level of immigration into a putative sink population. We use individual-based demographic models to estimate expected distributions of parent-offspring dyads under competing sink and closed-population models. By comparing the actual number of parent-offspring dyads (identified from multilocus genetic profiles) in a random sample of individuals taken from a population to expectations under these two contrasting demographic models, it is possible to estimate the rate of immigration and test hypotheses related to the role of immigration on population processes on an ecological timescale. The difference in the expected number of parent-offspring dyads between the two population models was greatest when immigration into the sink population was high, indicating that unlike traditional population genetic inference models, the highest degree of statistical power is achieved for the approach presented here when migration rates are high. We used the proposed genetic parentage approach to demonstrate that a threatened population of Marbled Murrelets (Braclhyrarmphus marmotus) appears to be supplemented by a low level of immigration (approximately 2-6% annually) from other populations.     

Rational decision processes and sex discrimination: Testing ‘rational’ bias theory

The extent to which sex discrimination is likely to occur as a consequence of manager-client relationships was examined in this test of rational bias theory. Results were gathered by means of a computerized survey technique. Findings indicated that discrimination is more likely to occur in relationships in which the client is relatively important to the manager, but less likely to occur, or be reversed, in the presence of conditions signaling that the client disapproves of discrimination. The findings partly supported the prediction that managers in relatively weaker positions more readily discriminate. The analysis offers theoretical and policy implications for future consideration.