Foraging shifts and visual preadaptation in ecologically diverse bats.

Changes in behaviour may initiate shifts to new adaptive zones, with physical adaptations for novel environments evolving later. While new mutations are commonly considered engines of adaptive change, sensory evolution enabling access to new resources might also arise from standing genetic diversity, and even gene loss. We examine the relative contribution of molecular adaptations, measured by positive and relaxed selection, acting on eye-expressed genes associated with shifts to new adaptive zones in ecologically diverse bats from the superfamily Noctilionoidea.

[Pneumopericardium in the newborn. Study of 5 cases and a review of the literature].

Experience with 572 events of mechanical ventilation that developed 5 cases of pneumopericardium thru the period from August 1975 to August 1979 is reported. From this series, at least two cases were in direct relationship with the administration of high mean ventilatory pressure; other two could be related to inadvertently PEEP; finally the remaining case is questioned to be a pericardium congenital defect since no relation with the other causes of pneumopericardium could be explained. Surviving from the pneumopericardium and from the drainage, pneumopericardium is commented according to what has being reported in the literature that follows about the same trend of our series where the relative fatality risk is higher when a pericardiumcentesis is practiced.