Aprender matemáticas con ordenadores

Utilizar el ordenador en la escuela no es una garantía de éxito didáctico si no se cumplen algunos requisitos, pero constituye una ayuda no suficientemente explorada en la mayoría de las materias. En el caso de las matemáticas, el ordenador permite diseñar actividades altamente motivadoras para el niño, a la vez que facilitar la integración de diferentes tipos de códigos, objetivos ambos difíciles de conseguir en los formatos de papel y lápiz habituales en las didácticas tradicionales. El autor de este artículo pasa revista a una serie de micromundos informáticos que permiten al profesor y al alumno librarse de tareas rutinarias y dedicarse a la exploración de las posibilidades del lenguaje matemático, a la verdadera tarea de aprender.     

The Use of Different Translation Devices to Analyze Knowledge-Building in a University Chemistry Classroom

Research in Science Education - This research draws on Legitimation Code Theory (LCT) to understand the epistemic dimension of the higher education classroom discourse of a professor who is well...     

A Remote Sensing Class Exercise to Study the Effects of El Niño in South America

Satellite remote sensing techniques can be used for conducting environmental change detection studies following a natural disaster. Modern computer technology and free access to global satellite imagery allows educators to introduce undergraduate students to the fields of remote sensing and encourage their scientific participation through a research assignment that also serves as an educational exercise. The undergraduate physical science laboratory manuals used in higher education that contain printed remote sensing material often fail to effectively achieve these goals. This class exercise utilizes digital satellite imagery for studying the floods that resulted in the Paraná River region in South America during El Niño 1997–98. In addition, it examines vegetation cover and spectral profiles from the study area in order to further understand and assess the changes that were caused by this recurrent climatic anomaly.     

Teaching strategies to create visual representations of key ideas in content area text materials: A longterm intervention inserted in school curriculum

This paper describes a long-term research in which middle-grade school children were taught how to represent visually text key ideas through idea-mapping techniques. It consists of three studies, one for each year of our research. Children were at sixth grade when the instruction began, and they were at eighth grade when it finished. Another group of children from a different public school served as control group. Instruction was very close to the real school conditions: instructors were ordinary teachers, instruction was inserted in the content area curriculum, and ordinary textbooks were regularly employed, though combined with specially elaborated materials. Results were positive in the case of the first and third year, depending on instructional conditions. Positive effects were found on recall, comprehension and learning, but they were different in the three studies. Theoretical and practical implications are discussed.     

La educación de los sentidos en la Argentina de Perón. El caso de la revista Noticioso y la cinematografía escolar

RESUMEN

En la Argentina de mediados del siglo XX comenzó con un fuerte sesgo estatal a pensarse en la cinematografía escolar como un eficaz método pedagógico de difusión de un pretendido ideario simultáneamente emancipador y propagandístico. Del mismo modo que otros gobiernos de diversas filiaciones ideológicas, la presidencia de Juan Domingo Perón estuvo signadas por una política de la imagen que se enfocó en educar los sentidos de las futuras generaciones de argentinos. En este caso se muestra una política en particular, como lo fue la revista Noticioso entre 1952 y 1955, cuyo análisis refleja el exponencial crecimiento del rol estatal, hasta ocupar un lugar central no sólo en la reproducción de cine educativo, sino también de la filmación, distribución y proyección de los celuloides. En síntesis, con la creación en 1948 del Departamento de Radioenseñanza y Cinematografía Escolar como organismo específicamente dedicado a la enseñanza audiovisual, y especialmente con la publicación de Noticioso, puede verse un síntoma de las políticas gubernamentales que el peronismo forjó para la formación de nuevos ciudadanos, en el marco de la pretendida Nueva Argentina.     

Interaction between cells in dielectrophoresis and electrorotation experiments

Progress in microelectrode-based technologies has facilitated the development of sophisticated methods for manipulating and separating cells, bacteria, and other bioparticles. For many of these various applications, the theoretical modeling of the electrical response of compartmentalized particles to an external field is important. In this paper we address the analysis of the interaction between cells immersed in rf fields. We use an integral formulation of the problem derived from a consideration of the charge densities induced at the interfaces of the particle compartments. The numerical solution by a boundary element technique allows characterization of their dielectric properties. Experimental validation of this theoretical model is obtained by investigating two effects: (1) The influence that dipolar “pearl chaining” has on the dielectrophoretic behavior of human T lymphocytes and (2) the frequency variation of the spin and orbital torques of approaching insulinoma β-cells in a rotating field.     

Landing techniques in volleyball

Knee injuries such as anterior cruciate ligament lesions and patellar tendonitis are very frequent in volleyball, and are often attributed to micro traumas that occur during the landing phase of airborne actions. The aim of the present study was to compare different jumping activities during official men's and women's volleyball games. Twelve top-level matches from the Italian men's and women's professional leagues were analysed. The jumps performed during the games were classified according to the landing technique used by the player (left or right foot or both feet together), court position, and ball trajectory. Chi-square analyses were performed to detect differences in landing techniques between the sexes, court positions, and trajectories when serving, attacking, blocking, and setting. Significant differences (P?相似文献   

An investigation into turn-away among information technology professionals in Brazil

Two important problems have been observed fairly frequently among information technology (IT) professionals, namely turn-over – where the IT professional moves to another company but still remains in the IT sector – and turn-away, in which the IT professional abandons the area in order to occupy a position in a different area, either in the same company or in another, sometimes assuming a managerial function. Few research papers were found with respect to the latter phenomenon. Based on that, the main thrust of this work is to understand how and why IT professionals in Brazil abandon their area, identifying typical characteristics in their career transition. Thus, from a literature review about career development and the analysis of the data collected, eight research hypotheses were developed in order to be analyzed by the researchers. A multiple case study method with several units of analysis was applied in two large companies in Brazil. In-depth interviews were conducted with IT professionals who had migrated to other areas within their organizations, they being considered the unit of analysis. The results accrued from this research reveal that IT professionals in Brazil need to have more growth opportunities than either their companies have been able to offer them or it is possible to offer within the technical arena.