Martin-Barbero, Canclini, Orozco: os impasses de uma teoria da comunicação latino-amricana

A pesquisa latino-americana de comunicação lembra uma ilha isolada, indiferente aos grandes debates filosófico- comunicacionais do século 20. Martín-Barbero ainda pensa segundo o modelo das totalidades e das hegemonias. Estudar a comunicação, para ele, é intervir, agir socialmente, e o processo comunicacional não está no ato de se assistir a TV, mas nas trocas que o receptor faz, lá fora, com sua comunidade. Néstor Canclini, trabalhando com arte e cultura popular, é mais realista, vê o consumo como feito da cumplicidade entre a sociedade civil e o Estado. Critica os que enaltecem os objetos da arte popular e se esquecem dos homens e de seus processos. Guillermo Orozco segue Martín-Barbero e critica as pesquisas que se ocupam do ato comunicacional específico. É alguém que busca a ressurreição dos agentes que vão esclarecer as pessoas como assistir “corretamente” à TV

Evolution of form and function: morphophysiological relationships and locomotor performance in tropidurine lizards

Locomotor capacity is often considered an excellent measure of whole animal performance because it requires the integrated functioning of many morphological, physiological (and biochemical) traits. However, because studies tend to focus on either structural or functional suits of traits, we know little on whether and how morphological and physiological traits coevolve to produce adequate locomotor capacities. Hence, we investigate the evolutionary relationships between morphological and physiological parameters related to exercise physiology, using tropidurine lizards as a model. We employ a phylogenetic principal component analysis (PCA) to identify variable clusters (factors) related to morphology, energetic metabolism and muscle metabolism, and then analyze the relationships between these clusters and measures of locomotor performance, using two models (star and hierarchical phylogenies). Our data indicate that sprint performance is enhanced by simultaneous evolutionary tendencies affecting relative limb and tail size and physiological traits. Specifically, the high absolute sprint speeds exhibited by tropidurines from the sand dunes are explained by longer limbs, feet and tails and an increased proportion of glycolytic fibers in the leg muscle, contrasting with their lower capacity for overall oxidative metabolism [principal component (PC1)]. However, when sprint speeds are corrected for body size, performance correlates with a cluster (PC3) composed by moderate loads for activity metabolic rate and body size. The simultaneous measurement of morphological and physiological parameters is a powerful tool for exploring patterns of coadaptation and proposing morphophysiological associations that are not directly predictable from theory. This approach may trigger novel directions for investigating the evolution of form and function, particularly in the context of organismal performance.

Weight loss in combat sports: physiological, psychological and performance effects

Abstract Background The present article briefly reviews the weight loss processes in combat sports. We aimed to discuss the most relevant aspects of rapid weight loss (RWL) in combat sports. Methods This review was performed in the databases MedLine, Lilacs, PubMed and SciELO, and organized into sub-topics: (1) prevalence, magnitude and procedures, (2) psychological, physiological and performance effects, (3) possible strategies to avoid decreased performance (4) organizational strategies to avoid such practices. Results There was a high prevalence (50%) of RWL, regardless the specific combat discipline. Methods used are harmful to performance and health, such as laxatives, diuretics, use of plastic or rubber suits, and sauna. RWL affects physical and cognitive capacities, and may increase the risk of death. Conclusion Recommendations during different training phases, educational and organizational approaches are presented to deal with or to avoid RWL.