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En este trabajo compartimos una experiencia pedagógica emergida inicialmente desde un curso de Investigación Cualitativa de la carrera de psicología de la Universidad de Antofagasta. Esta experiencia se centró en fortalecer nuestro plan de estudios mediante herramientas de investigación y divulgación científica a partir de lugares de articulación entre estudiantes y docentes e investigadoras con experiencia en metodologías cualitativas y estudios de género/feministas. La experiencia se concreta en una Jornada de Investigación Cualitativa autogestionada. Las Jornadas constituyeron un espacio de solidaridad académica y de reflexión/acción en torno al ejercicio pedagógico y procesos alternativos de producción de conocimientos dentro de las Ciencias Sociales, Artes y Humanidades, desafiando paradigmas hegemónicos. Asimismo, dentro de las instancias de discusión, se reflexionó sobre los desafíos de la investigación social, los modelos económicos que permean la educación, psicopatologización e individualización de la vida, así como las matrices de colonialidad del saber y androcentrismo anquilosadas en el quehacer científico.

One challenge in dynamic traffic assignment (DTA) modeling is estimating the finely disaggregated trip matrix required by such models. In previous work, an exogenous time distribution profile for trip departure rates is applied uniformly across all origin-destination (O-D) pairs. This article develops an endogenous departure time choice model based on an arrival time penalty function incorporated into trip distribution, which results in distinct demand profiles by O-D pair. This yields a simultaneous departure time and trip choice making use of the time-varying travel times in DTA. The required input is arrival time preferences, which can be disaggregated by O-D pair and may be easier to collect through surveys than the demand profile. This model is integrated into the four-step planning process with feedback, creating an extension of previous frameworks which aggregate over time. Empirical results from a network representing Austin, Texas indicate variation in departure time choice appropriate to the arrival time penalties and travel times. Our model also appears to converge faster to a dynamic trip table prediction than a time-aggregated coupling of DTA and planning, potentially reducing the substantial computation time of combined planning models that solve DTA as a subproblem of a feedback process. [ABSTRACT FROM AUTHOR]

The regional frequency analysis of extreme annual rainfall data is a useful methodology in hydrology to obtain certain quantile values when no long data series are available. The most crucial step in the analysis is the grouping of sites into homogeneous regions. This work presents a new grouping criterion based on some multifractal properties of rainfall data. For this purpose, a regional frequency analysis of extreme annual rainfall data from the Maule Region (Chile) has been performed. Daily rainfall data series of 53 available stations have been studied, and their empirical moments scaling exponent functions K(q) have been obtained. Two characteristics parameters of the K(q) functions ( γmax and K(0)) have been used to group the stations into three homogeneous regions. Only five sites have not been possible to include into any homogenous regions, being the local frequency analysis of extreme daily rainfall the most appropriate method to be used at these locations. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The trunk musculature of adult zebrafishes contains three major fiber types: adult red, intermediate, and white; and two minor populations: red muscle rim and scattered intermediate fibers. In this paper, the post hatching development of these muscle fiber types was studied by means of immunohistochemistry, using anti-myosin sera. Just hatched larvae contain two muscle fiber populations: embryonic red and white which give rise to the red muscle rim and the intermediate fibers respectively. Adult red fibers arise post hatching as a new separate population with distinct myosin properties. The differentiation of these fiber types occurs within the first four weeks after fertilization, when the adult pattern of peripheral axon bundles has become established. Differences in the muscle fiber type composition between the midbody and the tail myotomes become apparent in two month old fries. The number of scattered intermediate fibers increases from rostral to caudal, the opposite holds for the red muscle rim fibers. The red and intermediate area is triangular in the midbody; in the tail part it is stretched out along the lateral surface of the myotomes. These changes are considered as adaptations to improve the efficiency of the swiming performance. [ABSTRACT FROM AUTHOR]

In this study we tested the effects of immobilization and of spinal cord lesion on the differentiation of muscle fiber types in the myotomal muscle of the zebrafish. We found that the differentiation of embryonic red and white muscle fibers occurs in immobilized as well as in denervated myotomes of zebrafish embryos. Intermediate and adult red muscle fibers are not formed in denervated myotomes of larvae. Adult zebrafishes with spinal cord lesions in the anal region show abnormal undulating movements in the rostral part of the body. This change in muscle activity correlates with an increase in the number of intermediate scattered fibers. We conclude that direct contact with spinal cord motorneurons is not necessary for the differentiation of embryonic red and white fibers. The differentiation of intermediate muscle fibers is under extrinsic control. The factors that determine the formation of adult red fibers are not yet clear. [ABSTRACT FROM AUTHOR]

A light-microscopic immuno- and enzyme histochemical and an ultrastructural study has been made on the lateral body musculature of the teleost Brachydanio rerio in the adult stage and in early developmental stages. On basis of the myofibrillar and the metabolic properties, the following types of muscle fibers can be distinguished in the adult stage: superficial red fibers, which are slow-contracting and fatigue-resistant; and deep white fibers, which are fast-contracting and fatigue rapidly. In the white fibers a subgroup can be discerned that is similar to fast-contracting and fatigueresistant fibers of mammalian muscles. The origin of these different fiber types has been investigated in early embryonic and larval stages. All muscle cells pass through a stage in which they produce 'redlike' myofibrils that are immunologically similar to the fibrils of the slow contracting superficial muscle fibers. In all, except the superficial cells, there is a switch to the synthesis of 'whitelike' myofibrils. The 'redike' myofibrils have by then disappeared. The cause of this switch is not yet clear; mechanical factors may be involved, but a neuronal influence is unlikely. The adult fiber types develop as late as in the free-living larval stage from a common embryonic fiber type first by a differentiation in myofibrillar properties and subsequently by a differentiation in metabolic properties. [ABSTRACT FROM AUTHOR]