Energetic costs of performance in trained and untrained Anolis carolinensis lizards.

The energetic costs of performance constitute a non-trivial component of animals' daily energetic budgets. However, we currently lack an understanding of how those costs are partitioned among the various stages of performance development, maintenance and production. We manipulated individual investment in performance by training Anolis carolinensis lizards for endurance or sprinting ability. We then measured energetic expenditure both at rest and immediately following exercise to test whether such training alters the maintenance and production costs of performance. Trained lizards had lower resting metabolic rates than controls, suggestive of a maintenance saving associated with enhanced performance as opposed to a cost. Production costs also differed, with sprint-trained lizards incurring a larger energetic performance cost and experiencing longer recovery times compared with endurance trained and control animals. Although performance training modifies metabolism, production costs are probably the key drivers of trade-offs between performance and other life-history traits in this species.

Racial differences in time from prostate cancer diagnosis to treatment initiation: a population-based study.

BACKGROUND: Timely delivery of care has been identified by the Institute of Medicine as an indicator for quality health care, and treatment delay is a potentially modifiable obstacle that can contribute to the disparities among African American (AA) and Caucasian patients in prostate cancer recurrence and mortality. Using the Surveillance, Epidemiologic and End Results (SEER)-Medicare linked database, we compared time from diagnosis to treatment in AA and Caucasian prostate cancer patients. METHODS: A total of 2506 AA and 21,454 Caucasian patients diagnosed with localized prostate cancer from 2004 through 2007 and treated within 12 months were included. Linear regression was used to assess potential differences in time to treatment between AA and Caucasian patients, after adjusting for sociodemographic and clinical covariates. RESULTS: Time from diagnosis to definitive (prostatectomy and radiation) treatment was longer for AA patients in all risk groups, and most pronounced in high-risk cancer (96 versus 105 days, P < .001). On multivariate analysis, racial differences to any and definitive treatment persisted (ß = 7.3 and 7.6, respectively, for AA patients). Delay to definitive treatment was longer in high-risk (versus low-risk) disease and in more recent years. CONCLUSIONS: AA patients with prostate cancer experienced longer time from diagnosis to treatment than Caucasian patients with prostate cancer. AA patients appear to experience disparities across all aspects of this disease process, and together these factors in receipt of care plausibly contribute to the observed differences in rates of recurrence and mortality among AA and Caucasian patients with prostate cancer.