Driving safety improves after individualized training: An RCT involving older drivers in an urban area.

Objective: This study aimed to reproduce the results of a previous investigation on the safety benefits of individualized training for older drivers. We modified our method to address validity and generalizability issues. Methods: Older drivers were randomly assigned to one of the 3 arms: (1) education alone, (2) education + on road training, and (3) education + on road + simulator training. Older drivers were recruited from a larger urban community. At the pre- and posttests (separated by 4 to 8 weeks) participants followed driving directions using a Global Positioning System (GPS) navigation system. Results: Our findings support the positive influence of individualized on-road training for urban-dwelling older drivers. Overall, driving safety improved among drivers who received on-road training over those who were only exposed to an education session, F(1, 40) = 11.66, P = .001 (26% reduction in total unsafe driving actions [UDAs]). Statistically significant improvements were observed on observation UDAs (e.g., scanning at intersections, etc.), compliance UDAs (e.g., incomplete stop), and procedural UDAs (e.g., position in lane). Conclusion: This study adds to the growing evidence base in support of individualized older driver training to optimize older drivers' safety and promote continued safe driving.

Synthesis and surface properties of semi-fluorinated gemini surfactants with two reactive bromo pendant groups.

This paper presents a series of semi-fluorinated gemini surfactants with two bromo pendant groups. It reviews the effect of the number of methylene units in the spacer group between the two hydrophilic quaternary ammonium heads. Critical micelle concentration (cmc) and free energy of micellization (ΔG(M)(0)) of the title surfactants, in aqueous solution, have been investigated as a function of the number n of carbon atoms in the hydrocarbon spacer. We have pointed out a different behaviour as compared to Gemini hydrocarbon homologues. In the present study, when the number of methylene units (n) in the spacer increases, the cmc first decreases and reaches an optimum for (n=6), then it increases linearly from n≥6. Variations of cmc have been interpreted in terms of conformation changes of the surfactant ion and progressive penetration of the alkyl chain spacer in the micelle hydrophobic core. In this series, the increase of the hydrophobicity seems not to favour the micellisation process as expected, probably impacted by the mutual phobicity of the perfluorinated tails and the hydrocarbon spacer. A minimum is reached for a spacer with six methylene units which seems to be the optimal conformation. The free energy of micellization (ΔG(M)(0)) confirm this tendency.