Adult pedestrian behavior when accompanying children on the route to school

Objective: Pedestrian injuries are a major cause of morbidity and mortality to children, especially boys. Adults serve as pedestrian role models and provide learning opportunities for children when walking to school. The research objectives were to investigate adult pedestrian behavior when accompanying boys and girls. Methods: Behavioral observation of 140 adult pedestrians accompanying 4- to 9-year-old children was done in British residential locations. Observations took place at light-controlled crossings, speed-restricted school safety zones, and mid-block unmarked crossing sites. Behaviors observed included stopping at the curb, waiting at the curb, looking left and right before and during road crossing, holding hands, talking, and walking straight across. Results: In general, adults modeled safe road crossing behaviors. Adult safe behavior scores were higher when accompanying girls than when accompanying boys. No statistically significant differences were found by child age group. The fewest safe pedestrian behaviors were observed at light-controlled crossings. Conclusions: Adult pedestrians behave differently when with boys and girls and at different types of road crossing site. Interventions aimed at reducing pedestrian injuries to children may need to take these different everyday experiences into consideration

The effects of peer influence on adolescent pedestrian road-crossing decisions

Objective: Adolescence is a high-risk period for pedestrian injury. It is also a time of heightened susceptibility to peer influence. The aim of this research was to examine the effects of peer influence on the pedestrian road-crossing decisions of adolescents. Methods: Using 10 videos of road-crossing sites, 80 16- to 18-year-olds were asked to make pedestrian road-crossing decisions. Participants were assigned to one of 4 experimental conditions: negative peer (influencing unsafe decisions), positive peer (influencing cautious decisions), silent peer (who observed but did not comment), and no peer (the participant completed the task alone). Peers from the adolescent’s own friendship group were recruited to influence either an unsafe or a cautious decision. Results: Statistically significant differences were found between peer conditions. Participants least often identified safe road-crossing sites when accompanied by a negative peer and more frequently identified dangerous road-crossing sites when accompanied by a positive peer. Both cautious and unsafe comments from a peer influenced adolescent pedestrians’ decisions. Conclusions: These findings showed that road-crossing decisions of adolescents were influenced by both unsafe and cautious comments from their peers. The discussion highlighted the role that peers can play in both increasing and reducing adolescent risk-taking

Sub-Gap Structure in the Conductance of a Three-Terminal Josephson Junction

Three-terminal superconductor (S) - normal metal (N) - superconductor (S) Josephson junctions are investigated. In a geometry where a T-shape normal metal is connected to three superconducting reservoirs, new sub-gap structures appear in the differential resistance for specific combinations of the superconductor chemical potentials. Those correspond to a correlated motion of Cooper pairs within the device that persist well above the Thouless energy and is consistent with the prediction of quartets formed by two entangled Cooper pairs. A simplified nonequilibrium Keldysh Green's function calculation is presented that supports this interpretation.Comment: To appear in Physical Review

The Measurement of Human Chorionic Gonadotropin for Pregnancy Testing

/Among many measurable hormones, human chorionic gonadotropin (FICG) is commonly used for pregnancy testing because it is very sensitive and relatively specific. Pregnancy can be identified shortly after implantation. Because some reagents cross-react with luteinizing hormone (LH), the sensitivity of urine tests has been adjusted to maintain specificity. Radioreceptor assay s on serum are more sensitive than urine tests but similarly lack specificity. The problems of LH cross-reactivity are eliminated by antisera specific for the beta subunit. Quantitation of HCG provides additional information useful in diagnosing ectopic pregnancy, providing a prognosis in threatened abortion, and following neoplasms. Considerations of cost, availability, accuracy, and sensitivity determine which test should be selected