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W. Patrick Dickson 《Cultura y Educación》2013,25(3-4):23-38
Una de las ideas más viejas y resistentes que forman parte del acervo habitual de los críticos de la cultura es la de la competitividad e incompatibilidad de los lenguajes y sistemas de símbolos (palabra-imagen, etc.). Lo que parece ser sólo una manifestación más dè la necesidad de zanjar la complejidad de las cosas con la toma de partido y la división entre buenos y malos. Pero las investigaciones de los últimos años sobre creatividad e imagen y ahora sobre el ordenador, nos obligan a revisar la idea y a adoptar una posición más constructiva y optimista. El artículo de Dickson subraya, además de ese aspecto constructivo de la multi-representación, otro valor esencial y no demasiado comentado del ordenador: su capacidad de interlocutor y maestro de ceremonias en ese diálogo constructivo de lengua a lengua. Alumnos y profesores parecen tener un papel más gratificante en esa nueva concepción educativa del ordenador. 相似文献
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Replica obtained from micromolds patterned by simple photolithography has features with uniform heights, and attainable microchannels are thus quasi-two-dimensional. Recent progress in three-dimensional (3D) printing has enabled facile desktop fabrication of molds to replicate microchannels with varying heights. We investigated the replica obtained from four common techniques of 3D printing—fused deposition modeling, selective laser sintering, photo-polymer inkjet printing (PJ), and stereolithography (SL)—for the suitability to form microchannels in terms of the surface roughness inherent to the mechanism of 3D printing. There have been limited quantitative studies that focused on the surface roughness of a 3D-printed mold with different methods of 3D printing. We discussed that the surface roughness of the molds affected (1) transparency of the replica and (2) delamination pressure of poly(dimethylsiloxane) replica bonded to flat glass substrates. Thereafter, we quantified the accuracy of replication from 3D-printed molds by comparing the dimensions of the replicated parts to the designed dimensions and tested the ability to fabricate closely spaced microchannels. This study suggested that molds printed by PJ and SL printers were suitable for replica molding to fabricate microchannels with varying heights. The insight from this study shall be useful to fabricate 3D microchannels with controlled 3D patterns of flows guided by the geometry of the microchannels. 相似文献
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Andrea L Hergenroeder Jennifer S Brach Amy D Otto Patrick J Sparto John M Jakicic 《Cardiopulmonary Physical Therapy Journal》2011,22(3):11-20
Purpose: Little is known about limitations in physical function across BMI categories in middle aged women using both self-report and performance-based measures. Furthermore, the impact of BMI on the measurement of function has not been explored. The purpose of this study was to assess physical function in adult women across BMI categories using self-report and performance-based measures and determine the influence of BMI on the relationship between the measures. Methods: Fifty sedentary females (10 in each BMI category: normal weight, overweight, obese class I, II, and III) aged 51.2 ± 5.4 years participated. Assessments included demographics, past medical history, physical activity level, BMI, and self-report (Late Life Function and Disability Instrument) and performance-based measures of physical function (6-Minute Walk Test, timed chair rise, gait speed). Physical function was compared between BMI categories using analysis of variance. The influence of BMI on the relationship of self-report and performance-based measures was analyzed using linear regression. Results: Compared to those that were normal weight or overweight, individuals with obesity scored lower on the self-report measure of physical function (LLFDI) for capability in participating in life tasks and ability to perform discrete functional activities. On the performance-based measures, the individuals with obesity had slower gait speed compared to the normal and overweight weight groups. For the 6-Minute Walk Test and timed chair stands, individuals with obesity had poorer performance compared to those who were normal weight. Linear regression analyses revealed that BMI attenuated the relationship between the self-report and performance-based measures by approximately 50%. Conclusions: While those with severe obesity were most impaired, adult women with less severe obesity also demonstrated significant decrements in physical function.Key Words: obesity, physical function 相似文献