Representaciones imaginarias de la interacción y violencia en la escuela

School violence research (sociopaedagogical and psychosocial perspectives) has not appropiately taken into account interpersonal and imaginary elements that may be extremely relevant for the understanding of this phenomena. This article analizes the imaginaries that articulates the violence of youth groups in a context of interpersonal relationships in the institutional space of a Rio Claro (Brazil) secondary school. The results are based on the analysis of four youth groups discourses, gathered in succesive group interviews, as well as the drawings made and pictures taken on their respective schools. They show a strong imaginary of generalized violence, in and out the school, with a representation of the school as unfair and aggressor and the students, aggressors themselves, as humiliated and undervalued.

Estudio de efectos ambientales y genéticos que influyen en la producción de leche y duración de lactación en bovinos de raza guzerat

Objective of present work was study a influence of environmental and genetic effects over characteristics of milk total production (PL) and lactation duration (DL), from 2572 lactations of 477 Guzerat cows, collected since 1957 to 2002, in Rio de Janeiro State. Environmental effects were analyzed by an statistical model that include male randomized effect, fixed effect of contemporary group, and the (co)variables age of cow (lineal and quadratic) and lactation duration. The contemporary group had significant effect just for PL. Bayesian inference was used to obtain estimatives of genetic parameters over an animal model, in which was included as fixed effect the contemporary group and the covariables age of cow (linear and quadratic). The estimates of heritability and repeatability were 0.36 and 0.75 for PL and 0.29 and 0.36 for DL, respectively. The estimated genetic correlation was 0.97. The heritability estimates for PL and DL were moderate, indicating that it is possible answer to the selection of the characteristics under study. The genetic correlation was high and indicates that selection for increase milk production will be accompanied with increase in lactation duration.