[Establishment and development of Tabebuia rosea (Bignoniaceae) seedlings in a semideciduous tropical forest under management, Pacific coast of Mexico].

We evaluated the effect of soil "scarification" and vegetation clearing treatments on the natural regeneration and initial development of Tabebuia rosea (Bertold) DC. seedlings in a moderate sized semideciduous tropical forest subjected to wood harvesting on the coast of Jalisco, Mexico. The treatments were applied under "seed" trees, and the number of germinated seedlings and their development were evaluated for nine months.

Effects of training on the tolerance to high-intensity exercise in patients with severe COPD.

Background: There has been no systemic investigation of the effects of training on endurance at different high-intensity work rates in patients with COPD to date.

Objectives: We wanted to determine the effects of intense endurance training on tolerance to several high-intensity work rates and to establish the relationship between power (WR) and its tolerable duration (t) (t = W'/(WR - CP), being W', the curvature constant, thought to be reflective of anaerobic energy availability and/or tolerance to the uncomfortable sensations associated with the high-intensity exercise, and CP the critical power.

Methods: We studied 27 patients: age 62 +/- 5 years; FEV(1) 1.