Mathematics

  2010 MAR 23 - (VerticalNews.com) -- "In two experiments, human participants searched in dynamic three-dimensional virtual-environment rectangular enclosures. Unlike previous studies involving learning of features and geometry, we trained features and geometry separately before placing them in conflict," investigators in the United States report.

  "Specifically, participants learned to respond to rewarded features located along the principle axis of a rectangular search space and to respond to rewarded geometry of a rectangular search space in separate training phases followed by a single test trial. During the test trial, features and geometry were placed in conflict by situating rewarded bins during feature training in unrewarded geometric corners from geometry training and unrewarded bins during feature training in rewarded geometric corners from geometry training. Results of Experiment 1 indicated that although all participants learned features and geometry at an equivalent rate and to an equivalent level, performance during the test trial indicated no preferential responding to features or geometry. However, choice reaction time was significantly longer during the test trial compared to that of last feature and last geometry training trials. Experiment 2 attempted to dissociate information content of features and geometry from their acquired associative strength by rewarding only one geometric corner during geometry training. Results of Experiment 2 indicated that although features had presumably acquired greater associative strength relative to that of geometry by the end of training, performance during the test trial indicated no preferential responding to features or geometry. As in Experiment 1, choice reaction time was significantly longer during the test trial compared to that of last feature and last geometry training trials," wrote B.R. Sturz and colleagues, Armstrong Atlantic State University ...read more

  2010 MAR 23 - (VerticalNews.com) -- According to recent research published in the journal Langmuir, "It is now becoming possible to control and tailor micro/nanoscale chemical structures with different geometrical patterns on various substrates to achieve so-called superhydrophobic surfaces, which show promising industrial applications. In spite of significant advances in preparation of such surfaces, to date the effects of surface patterns or geometries on superhydrophobicity have not been understood completely, in particular, in the theoretical aspect. ...read more

  2010 MAR 23 - (VerticalNews.com) -- "Reparametrization invariant dynamics on a sphere, being parameterized by angular momentum coordinates, represents an example of noncommutative theory. It can be quantized according to Berezin-Marinov prescription, replacing the coordinates by Pauli matrices," scientists writing in the journal Symmetry Integrability and Geometry - Methods and Applications report.

  "Following the scheme, we present two semiclassical models for description of spin without use of Grassman variables. The first model implies Pauli equation upon the canonical quantization," wrote A.A. Deriglazov and colleagues ...read more