Nonlinear diffusion equations with degenerate fast-decay mobility by coordinate transformation

We prove an existence and uniqueness result for solutions to nonlinear diffusion equations with degenerate mobility posed on a bounded interval for a certain density $u$. In case of \emph{fast-decay} mobilities, namely mobilities functions under a Osgood integrability condition, a suitable coordinate transformation is introduced and a new nonlinear diffusion equation with linear mobility is obtained. We observe that the coordinate transformation induces a mass-preserving scaling on the density and the nonlinearity, described by the original nonlinear mobility, is included in the diffusive process. We show that the rescaled density $\rho$ is the unique weak solution to the nonlinear diffusion equation with linear mobility. Moreover, the results obtained for the density $\rho$ allow us to motivate the aforementioned change of variable and to state the results in terms of the original density $u$ without prescribing any boundary conditions

Is the SAT the Root of all Evil? Reviewing the Evidence on Admission Policies and Diversity in Higher Education

It is imperative to achieve diversity in Higher Education. With affirmative action policies under fire, it is becoming difficult to enroll a diverse student body. Many critics see standardized tests, and the SAT in particular, as contributing to the problem. This paper reviews research on such criticism, about suggested alternative approaches, and regarding recommendations on how to improve the current situation. In general, this review finds little evidence against a judicious use of the SAT. Also, alternative approaches such as percent plans or abolishing the SAT have had little success in increasing diversity. However, most specialists agree that a comprehensive approach to college admissions is needed

The cognitive representation of action: modulation effects between action and perception as mediated by the event cosing

Gaspare Galati, Teresa Scalisi, Pierluigi Zoccolott

Effects of Illustrations on Retention and Visual Attention Using Authentic Textbooks

Problem The purpose of this exploratory study was to validate a model of multimedia learning, incorporating learner-specific characteristics such as intelligence, memory, and measures of visual attention. Method The sample consisted of 62 Andrews University students (26 males, 36 females, and mean age 21.7). Data were gathered by means of standardized testing (RPM, WAIS- III) and eye-tracking. MLR was used to determine significant visual attention predictors for retention and SEM was used to test a hypothesized model of multimedia learning. Results Multiple Linear Regression was significant (p.05; GFI = .923; CFI = .986; RMSEA = .043; PGFI = .451) proving the hypothesized model’s excellent fit to the data. Conclusions This exploratory study indicates that there are different learning strategies in a college population that are not related to characteristics such as intelligence or working memory. These strategies are learned or acquired and have thus clear implications for practice