El ordenador como metáfora: Las posibilidades educativas de LOGO     

Eduardo Martí 《Infancia y Aprendizaje》2013,36(26):47-64

Resumen

El autor considera al LOGO como un prototipo de la utilización educativa de los microordenadores que hace hincapié en la autonomía del aprendizaje y a sus aspectos heurísticos.

Desde postulados teóricos de la psicología genética de Piaget, analiza algunas de las particularidades psicológicas y pedagógicas de LOGO: unidades de base significativas para el niño, carácter constructivo e interactivo del aprendizaje, estatuto positivo del error, posibilidad de reflexionar sobre la propia actividad de aprendizaje.

Estos puntos son ilustrados con ejemplos de conductas de niños aprendiendo a programar con LOGO.  相似文献   

When access to drugs meets catch-up: Insights from the use of CL threats to improve access to ARV drugs in Brazil     

Shyama V. Ramani  Eduardo Urias 《Research Policy》2018,47(8):1538-1552

Access to affordable lifesaving medicines is considered a human right. This leads to a question largely understudied in the catch-up literature on accumulation of industrial capabilities. Can the need to improve access to an essential commodity impact the sectoral catch-up trajectory of the corresponding industry? In 1996, Brazil initiated a policy of universal and free access to highly-active ARV therapy, which put an enormous pressure on the Brazilian Ministry of Health (MoH). In order to ensure an adequate supply of ARVs in the public healthcare system with a limited budget, MoH started negotiating price reductions for high-cost patented drugs, often deploying the threat of using compulsory licensing. Through a scoping review of the literature and construction of the Brazilian case study, the paper explores how the need to access is impacted by prior catch-up in the pharmaceutical sector and triggers in turn future sectoral catch-up. It shows that price negotiations may or may not impact both catch-up and access positively. Catch-up can provide bargaining strength in price negotiations and have a positive inter-temporal impact on both future catch-up and access. However, results suggest that only successful catch-up can lead to long term access, as the capabilities accumulated in aborted catch-up are not sufficient for large scale production of low cost essential medicines. Thus, industrial policy and health policy can impact one another and twining between catch-up and access can be helpful.  相似文献   

Parasympathetic activity delayed after self-paced exercise     

Lucas Rosiello Trojbicz  Mayara Vieira Damasceno  Leonardo Alves Pasqua  Arthur Fernandes Gáspari  Adriano Eduardo Lima-Silva 《European Journal of Sport Science》2018,18(6):842-850

The main purpose of this study was to compare the effect of the constant load and self-paced exercise with similar total work on autonomic control after endurance exercise. Ten physically active men were submitted to (i) a maximal incremental exercise test, (ii) a 4-km cycling time trial (4-km TT), and (iii) a constant workload test with identical total external work performed at 4-km TT. Gas exchange was measured throughout the tests, while blood lactate, heart rate, and heart rate variability (HRV) were measured during the passive recovery. Power output measured at the last lap (i.e. 3600–4000?m) of 4-km TT (316?±?89?W) was statistically higher than power output measured at the end of the constant workload exercise (211?±?42?W). The 4-km TT produced higher values of blood lactate concentration (8.8?±?2.1?mmol?L^?1) than the constant workload test (7.8?±?2.1?mmol?L^?1). The heart rate recovery measured at 60?s (constant workload: 37?±?7?bpm; 4-km TT: 30?±?6) and 120?s (constant workload: 57?±?9?bpm; 4-km TT: 51?±?9?bpm) were higher in the constant workload than in the self-paced exercise. The HRV (i.e. RMSSD30s) was statistically higher in the constant load exercise measured at 120, 420, 450, 480, 540, and 570?s than the self-paced exercise. These findings suggest that the autonomic control responses were dependent of the endurance exercise modalities, with parasympathetic activity being delayed after self-paced exercise, as evidenced by post-exercise heart rate indices.  相似文献   

Fast distributed algebraic connectivity estimation in large scale networks     

Eduardo Montijano  Juan I. Montijano  Carlos Sagues 《Journal of The Franklin Institute》2017,354(13):5421-5442

This paper presents a distributed method to estimate the algebraic connectivity of fixed undirected communication graphs. The proposed algorithm uses bisection to estimate the second smallest eigenvalue of the Laplacian matrix associated to the graph. In order to decide the sub-interval in which the eigenvalue is contained, a distributed averaging algorithm based on Chebyshev polynomials is considered together with a max consensus algorithm. The information exchanged by neighbors in the graph each communication round is constant and independent of the size of the network, making it scalable to large networks. Besides, exploiting the convergence properties of Chebyshev polynomials we provide a direct estimation of the algebraic connectivity so that, instead of the midpoint of the bisection interval, the new approximation can be used. Finally, our algorithm also provides upper and lower bounds on the algebraic connectivity and an estimation of the Fiedler eigenvector associated to it. Simulations in large networks demonstrate the scalability and accuracy of the algorithm.  相似文献   

A school-based motivational intervention to promote physical activity from a self-determination theory perspective     

David González-Cutre  Ana C. Sierra  Vicente J. Beltrán-Carrillo  Manuel Peláez-Pérez  Eduardo Cervelló 《The Journal of educational research》2018,111(3):320-330

The authors analyzed the effects of a multidimensional intervention to promote physical activity (PA) in school, based on self-determination theory. The study involved 88 students, between 14 and 17 years old, who were divided into a control group (n = 59) and an experimental group (n = 29). In the experimental group, a 6-month intervention was conducted, applying a teaching unit of fitness and health in physical education (PE) classes, an extracurricular program of healthy PA, and meetings with families. Questionnaires were administered to measure different motivational variables and PA levels at four time points. Significant differences were found in favor of the experimental group in parental and peer autonomy support; integrated regulation in PE; autonomy, intrinsic, and identified regulation in leisure-time PA; moderate, hard, and very hard PA; and physical self-worth. Motivational effects were maintained over time but the effects on PA levels disappeared at 6 months.  相似文献   

Memory for recent actions in the bottlenosed dolphin (Tursiops truncatus): Repetition of arbitrary behaviors using an abstract rule     

Eduardo Mercado  Scott O. Murray  Robert K. Uyeyama  Adam A. Pack  Louis M. Herman 《Learning & behavior》1998,26(2):210-218

Little is known about how animals represent their own actions in working memory. We investigated whether bottlenosed dolphins could recall actions they had recently performed and reveal those recollections using an abstract rule. Two dolphins were trained to respond to a specific gestural command by repeating the last behavior performed. Both dolphins proved to be able to repeat a wide variety of behaviors on command and were able to generalize the repeating rule to novel behaviors and situations. One dolphin was able to repeat all 36 behaviors she was tested on, including behaviors involving multiple simultaneous actions and self-selected behaviors. These results suggest that dolphins can flexibly access memories of their recent actions and that these memories are of sufficient detail to allow for reenactments. The repeating task can potentially be used to investigate short-term action and event representations in a variety of species.  相似文献   

Bar velocities capable of optimising the muscle power in strength-power exercises     

Irineu Loturco  Lucas Adriano Pereira  Cesar Cavinato Cal Abad  Facundo Tabares  José Eduardo Moraes  Ronaldo Kobal 《Journal of sports sciences》2017,35(8):734-741

This study aimed at testing whether there are mean propulsive velocities (MPVs) capable of maximising the mean propulsive power (MPP) during the execution of bench press (BP), bench throw (BT), half squat (HS) and jump squat (JS). Additionally, we assessed the differences in MPP/MPV between ballistic and traditional exercises. Seventeen male rugby sevens players performed MPP tests in BP, BT, HS and JS and maximum isometric force (MIF) tests in HS and BP. The JS presented higher MPP (977.4 ± 156.2 W) than the HS (897.9 ± 157.7 W) (P < 0.05); the BP (743.4 ± 100.1 W) presented higher MPP than the BT (697.8 ± 70.4 W) (P < 0.05). Ballistic exercises presented higher optimum MPV (JS = 1.02 ± 0.07 m·s^?1; BT = 1.67 ± 0.15 m·s^?1) than traditional exercises (HS = 0.93 ± 0.08 m·s^?1; BP = 1.40 ± 0.13 m·s^?1) (P < 0.05). The optimum MPP in the JS, BT, HS and BP occurred at 28.2 ± 5.79, 23.3 ± 4.24, 32.4 ± 9.46 and 27.7 ± 5.33% of the MIF, respectively. The coefficient of variation (CV) of MPV at optimum MPP ranged from 7.4% to 9.7%, while the CV of %MIF ranged from 18.2% to 29.2%. The MPV is a more precise indicator of the optimum loads than the percentages of MIF due to its low inter-subject variability as expressed by CV. Therefore, MPV can be used to determine the optimum power load in the four investigated exercises.  相似文献   

Estudio del proceso de clasificación: ¿Concepción digital o analógica?     

Eduardo Martí 《Infancia y Aprendizaje》2013,36(12):71-79

Resumen

El autor después de exponer los dos modelos (analógico y digital) que los psicólogos han empleado hasta hoy para describir el proceso de clasificación, propone desde un punto de vista genético una crítica de dicha alternativa.

Para explicar el fenómeno de la clasificación, los psicólogos han propuesto dos modelos: el digital (según el cual pertenecer a una clase es cuestión de todo o nada) y el analógico (que explica la formación de las clases en torno a un prototipo). Sin embargo, la Psicología Genética argumenta que para los niños los prototipos serán diferentes a edades diferentes; para un mismo sujeto el prototipo podría variar según el contexto y los objetivos de la clasificación. Para el enfoque genético ambas concepciones no deben ser consideradas como excluyentes o incompatibles. A partir de los seis años de edad, ambas pueden ser adecuadas para describir las relaciones de semejanza entre objetos, ya que los niños o bien optan por una u otra manera o escogen ambas.  相似文献   

Un programa para la enseñanza de la comprensión de ideas principales de textos expositivos     

Eduardo Vidal-Abarca 《Infancia y Aprendizaje》2013,36(49):53-71

Resumen

Este artículo presenta una investigación llevada a cabo con niños de 5.° curso de EG B (11 años) los cuales fueron instruidos en la captación de ideas prinápales de textos expositivos con estructura enumerativa y comparativa, y en la formation de la macroestructura textual. Un grupo de niños de un colegio fueron entrenados con una metodología de instrucción directa mientras otro grupo equivalente de un centro distinto sirvió como grupo de control. Se tomaron tres tipos de medidas dependientes tras la lectura de diversos textos con un diseño pretest- postest incluyendo cada uno de ellos varias pruebas. El primer tipo de medidas se refería a la captación de ideas prinápales mientras el segundo y el tercero medían la conáencia de estructura textual y el recuerdo respectivamente. Los resultados mostraron una ejecución significativamente mejor del grupo experimental en el postest con respecto al grupo control en la mayor parte de las medidas dependientes. Tras un período de seguimiento de varios meses se aplicaron de nuevo algunas pruebas manteniéndose las mejoras del grupo experimental.  相似文献   

Performing in a multi-cultural context: The role of personality     

Michael J. Burke  Marla Baskerville Watkins  Eduardo Guzman   《Int J Intercult Relat》2009,33(6):475-485

Performance in situations where individuals from multiple countries are operating in a foreign culture is an underexplored domain of organizational behavior. We test hypothesized relationships between Big Five personality factors and dimensions of international performance using a sample of 232 international business students from 14 countries studying in Mexico. The results indicate differential relationships between personality factors and performance dimensions that emphasize interacting with host nationals and students from other countries, adjusting to a foreign environment, and maintaining a positive attitude in a foreign country. We discuss theoretical and practical implications for understanding and influencing performance in multi-cultural contexts.  相似文献