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Introduction: Resistance exercise (RE) stimulates a muscle protein anabolic response partially through enhanced satellite cell (SC) activity, however, age- and gender-related changes in SC content over a 24-h time course are not known. Methods: Ten young (27 ± 2 years) men and women and 11 older (70 ± 2 years) men and women performed an acute bout of RE. Myofiber and SC characteristics were determined from muscle biopsies of the vastus lateralis using immunohistochemistry. Immunoblotting was used to determine phosphorylation of cyclin-dependent kinase-2 and protein expression of p27Kip1 and cyclin D1. Results: Pax7+ SC were significantly increased in young men 24 h following RE. Percent SC were significantly increased in older women at 6 and 24 h following RE. Aging decreased myonuclear domain and increased protein expression of p27Kip1. Conclusions: An acute bout of RE increases SC content in young men at 24 h and older women at 6 and 24 h. Muscle Nerve 46: 51–59, 2012

Video detection has become an increasingly popular technology for vehicle detection at signalized intersections. Among the potential disadvantages of this technology is the tendency of video detectors to activate early at night due to headlight reflection on the pavement. This early activation results in a dramatic increase in the length of the effective vehicle detection zone. This observed variation in the effective length of the vehicle detection zone that varies by ambient lighting condition and camera placement presents a very serious impediment for traffic engineers to design vehicle extension intervals that operate consistently during day, night, and transition periods. Further, the stochastic variation in the length of the vehicle detection zone length has the potential to create driver expectancy issues. Tables are included that report the observed average and range of detection zone length variations for 16 observed video cameras that were extensively calibrated by the manufacturer at the test site. The paper concludes by recommending near-side placement of video detection devices to reduce the stochastic variation in detection zone length.