Políticas y prácticas de informática educativa en América Latina y El Caribe

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Gestión de la informática en las empresas ferroviarias de América Latina y España

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O lema aprender a aprender na literatura de informática educativa

This paper makes a characterization of pedagogical conceptions found in the educational informatics literature in Brazil as well as in the work of Seymour Papert given the undeniable influence of this author in that literature. We identified a strong hegemony in this field of learning-to-learn pedagogy by means of constructivism, constructionism, learning projects and pedagogy of competencies among others. We make a critical analysis of these trends in light of the historical-critical pedagogy pointing to a number of aspects that need further discussion, highlighting the problematic opposition between teaching and learning.

Política industrial y desarrollo reciente de la informática en la Argentina

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Identification of transmission line parameters from temporal measurements of currents and voltages in their terminals: Influence oh the length line

The objective of this paper is to show a methodology to estimate transmission line parameters. The method is applied in a single-phase transmission line using the method of least squares. In this method the longitudinal and transversal parameters of the line are obtained as a function of a set of measurements of currents and voltages (as well as their derivatives with respect to time) at the terminals of the line during the occurrence of a short-circuit phase-ground near the load. The method is based on the assumption that a transmission line can be represented by a single circuit π. The results show that the precision of the method depends on the length of the line, where it has a better performance for short lines and medium length. © 2012 IEEE.

Bothropstoxin-I reduces evoked acetylcholine release from rat motor nerve terminals: Radiochemical and real-time video-microscopy studies

Understanding the biological activity profile of the snake venom components is fundamental for improving the treatment of snakebite envenomings and may also contribute for the development of new potential therapeutic agents. In this work, we tested the effects of BthTX-I, a Lys49 PLA2 homologue from the Bothrops jararacussu snake venom. While this toxin induces conspicuous myonecrosis by a catalytically independent mechanism, a series of in vitro studies support the hypothesis that BthTX-I might also exert a neuromuscular blocking activity due to its ability to alter the integrity of muscle cell membranes. To gain insight into the mechanisms of this inhibitory neuromuscular effect, for the first time, the influence of BthTX-I on nerve-evoked ACh release was directly quantified by radiochemical and real-time video-microscopy methods. Our results show that the neuromuscular blockade produced by in vitro exposure to BthTX-I (1 μM) results from the summation of both pre- and postsynaptic effects. Modifications affecting the presynaptic apparatus were revealed by the significant reduction of nerve-evoked [3H]-ACh release; real-time measurements of transmitter exocytosis using the FM4-64 fluorescent dye fully supported radiochemical data. The postsynaptic effect of BthTX-I was characterized by typical histological alterations in the architecture of skeletal muscle fibers, increase in the outflow of the intracellular lactate dehydrogenase enzyme and progressive depolarization of the muscle resting membrane potential. In conclusion, these findings suggest that the neuromuscular blockade produced by BthTX-I results from transient depolarization of skeletal muscle fibers, consequent to its general membrane-destabilizing effect, and subsequent decrease of evoked ACh release from motor nerve terminals. © 2012 Elsevier Ltd.

El comercio internacional de servicios en el área de la informática, la información electrónica y las telecomunicaciones

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Análise ergonômica em laboratórios de informática nas instituições públicas educacionais de ensino fundamental de Bauru

Pós-graduação em Design - FAAC

Um estudo exploratório sobre o uso da informática na resolução de problemas trigonométricos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Informática e ensino de química: investigando a experiência de um grupo de professores

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Professores-multiplicadores: uma maneira de organizar a formação de professores de matemática para o uso da informática na escola

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Expectativas e dificuldades de licenciandos em matemática relativas ao uso da tecnologia informática

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)