Reflexiones acerca de la alfabetización.

Sin resume

Cognición y Representación: Persiguiendo un Sueño

La verdadera equidad educacional no se logra con sólo abrir los colegios a todos los niños, sino ofreciéndoles oportunidades de éxito escolar a través del cultivo de la diversidad cognoscitiva, considerando el rol de la cultura y de la escuela en este proceso. La mente es un logro cultural cuya conformación está influida significativamente por el tipo de experiencias vivenciadas por una persona en el transcurso de su vida. Las formas de representación que se usan como sistemas de símbolos para representar lo que se piensa influyen en los procesos de pensamiento y en los productos de éste, desarrollan diferentes destrezas cognoscitivas e inciden en lo que uno es capaz de ver y de representar. En el trabajo docente, ellas pueden combinarse para enriquecer el conjunto de recursos ofrecidos a los alumnos a modo de que entiendan ideas importantes, útiles, hermosas y poderosas; que piensen analítica y críticamente; que especulen imaginativamente para ver conexiones en las ideas y que usen lo que saben para mejorar sus vidas y contribuir a la cultura

First L-band Interferometric Observations of a Young Stellar Object: Probing the Circumstellar Environment of MWC 419

We present spatially-resolved K- and L-band spectra (at spectral resolution R = 230 and R = 60, respectively) of MWC 419, a Herbig Ae/Be star. The data were obtained simultaneously with a new configuration of the 85-m baseline Keck Interferometer. Our observations are sensitive to the radial distribution of temperature in the inner region of the disk of MWC 419. We fit the visibility data with both simple geometric and more physical disk models. The geometric models (uniform disk and Gaussian) show that the apparent size increases linearly with wavelength in the 2-4 microns wavelength region, suggesting that the disk is extended with a temperature gradient. A model having a power-law temperature gradient with radius simultaneously fits our interferometric measurements and the spectral energy distribution data from the literature. The slope of the power-law is close to that expected from an optically thick disk. Our spectrally dispersed interferometric measurements include the Br gamma emission line. The measured disk size at and around Br gamma suggests that emitting hydrogen gas is located inside (or within the inner regions) of the dust disk.Comment: Accepted for publication in Ap

A Cautionary Note about the Use of Estimated Homicide Data for Cross-National Research

A major development in criminology in recent years has been the efforts by the World Health Organization to provide reasonably reliable estimates of homicide rates for a large number of nations. In some instances, these estimates entail adjustments of the records on homicide from vital statistics or criminal justice sources submitted by participating nations. These adjustments are designed to deal with underreporting and detected anomalies. In other instances, the estimates are generated by regression modeling. The purpose of this research note is to raise awareness among the community of homicide researchers of the nature of the WHO homicide estimates and to offer caution about their appropriate use for cross-national research

High Resolution K-band Spectroscopy of MWC 480 and V1331 Cyg

We present high resolution (R=25,000-35,000) K-band spectroscopy of two young stars, MWC 480 and V1331 Cyg. Earlier spectrally dispersed (R=230) interferometric observations of MWC 480 indicated the presence of an excess continuum emission interior to the dust sublimation radius, with a spectral shape that was interpreted as evidence for hot water emission from the inner disk of MWC 480. Our spectrum of V1331 Cyg reveals strong emission from CO and hot water vapor, likely arising in a circumstellar disk. In comparison, our spectrum of MWC 480 appears mostly featureless. We discuss possible ways in which strong water emission from MWC 480 might go undetected in our data. If strong water emission is in fact absent from the inner disk, as our data suggest, the continuum excess interior to the dust sublimation radius that is detected in the interferometric data must have another origin. We discuss possible physical origins for the continuum excess.Comment: 29 pages, 5 figures, to appear in Ap