El impacto de la crisis con Bolivia y la Guerra del Chaco (1932 – 1935) en la educación

Este trabajo pretende ampliar la mirada de los estudios históricos en relación con el impacto de la Guerra del Chaco sobre las escuelas primarias y colegios secundarios del Paraguay. Con base en la bibliografía ya existente, a la que se suma el uso inédito de archivos escolares, se trata de reconstruir razonablemente cómo fueron afectadas las políticas educativas, las comunidades educativas, la inserción y la exclusión escolar, así como el financiamiento educativo. Igualmente, muestra el impacto de las movilizaciones sobre la composición del magisterio por sexos. Propone también acercamientos en torno a la relación entre guerra, el currículum y los programas de estudio, a partir del análisis de los textos escolares y los mapas entregados a las instituciones educativas; y la descripción existente en algunas memorias sobre las actitudes de la niñez y la adolescencia escolarizadas ante la Guerra

Full-Body Kinematics and Vertical Ground Reaction Forces in Elite Ten-Pin Bowling:A Field Study

The purpose was to investigate full-body kinematics and vertical ground reaction forces in the lower extremities of the delivery and to determine delivery changes over time after many deliveries in ten-pin bowling. Six male elite ten-pin bowlers completed six bouts of twelve bowling deliveries, all strike attempts, while measuring full-body kinematics and vertical ground reaction forces. Full-body joint angles, peak vertical ground reaction forces in the feet, vertical breaking impulse, centre of mass velocity, bowling score, and ball release velocity (BR vel) were measured. Results revealed that the BR vel was significantly decreased over bouts (p &lt; 0.001). Additionally, increased flexion of the dominant wrist (p &lt; 0.001) and elbow (p = 0.004) prior to ball release (BR) and increased pronation of the dominant wrist during BR (p = 0.034) were observed at later bouts. It was concluded that these kinematic changes in the dominant wrist and elbow prior to and during BR were performed to compensate for the change in traction between ball and lane during a bowling match. This, in turn, caused a decrease in BR vel. A conservation of energy perspective was discussed to highlight training applications and possibilities to enhance elite athletes’ bowling performance.</p

Inverted regions induced by geometric constraints on a classical encounter-controlled binary reaction

The efficiency of an encounter-controlled two-channel reaction between two independently-mobile reactants on a lattice is characterized by the mean number \rt of steps to reaction. The two reactants are distinguished by their mass with the "light" walker performing a jump to a nearest-neighbor site in each time step, while the "heavy" walker hops only with a probability $p$; we associate $p$ with the "temperature" of the system. Lattices subject to periodic and to confining boundary conditions are considered. For periodic lattices, depending on the initial state, the reaction time either falls off monotonically with $p$ or displays a local minimum with respect to $p$; occurrence of the latter signals a regime where the efficiency of the reaction effectively decreases with increasing temperature. Such behavior disappears if the jump probability of the light walker falls below a characteristic threshold value. In lattices subject to confining boundary conditions, the behavior is more complex. Depending on the initial conditions, the reaction time as a function of $p$ may increase monotonically, decrease monotonically, display a single maximum or even a maximum and minimum. These inverted regions are a consequence of a strictly classical interplay between excluded volume effects implicit in the specification of the two reaction channels, and the system's dimensionality and spatial extent. Our results highlight situations where the description of an encounter-controlled reactive event cannot be described by a single, effective diffusion coefficient. We also distinguish between the inversion region identified here and the Marcus inverted region which arises in electron transfer reactions.Comment: revtex4 manuscript, approx. 45 pages, contains 18 figures and 18 tables, uses placeins.sty fil