We compare the performance of the red-green, blue-yellow and luminance postreceptoral mechanisms on a contour integration task requiring the linking of oriented Gabor elements across space to extract a winding 'path' or contour. We first establish that for all three mechanisms curvature and contrast are independent; losses in performance due to one cannot be compensated by changes in the other....

We study a new s-process path through an isomer of Re to improve a Re-Os nucleo-cosmochronometer. The nucleus Re is produced by this new path of Re(n,γ)Re(n,γ)Re. We measure a ratio of neutron capture cross-sections for the Re(n,γ)Re and Re(n,γ)Re reactions at thermal neutron energy because the ratio with the experimental uncertainty has not been reported. Using an activation method with reacto...

We present a derivation of the Schrödinger equation for a path integral of a point particle in a space with curvature and torsion which is considerably shorter and more elegant than what is commonly found in the literature. ∗Permanent address: Department of Theoretical Physics, Faculty of Physics, University of Sofia, Bull. 5 James Boucher, Sofia 1126, Bulgaria. Work supported by the Commission...

Alginate hydrogels are versatile self-assembling biocompatible materials with diverse biomedical and food industrial applications, which includes uses in encapsulation, (drug) delivery tissue engineering. Hydrogel formation requires cross-linking, for alginates is often done calcium ions that engage specific interactions the polysaccharide carboxylic acid groups. Water molecules also hydrate th...

An elastic analysis is presented for the tensile stretching and bending of a plate containing a surface crack penetrating part-through the thickness, Fig. 1. The treatment is approximate, in that the two-dimensional generalized plane stress and KirchhoffPoisson plate bending theories are employed, with the part-through cracked section represented as a continuous line spring. The spring has both...

In previous work of the second author a rigorous mathematical foundation for re-encoding one evolutionary search algorithm by another has been developed. A natural issue to consider then is the complexity of deciding whether or not a given evolutionary algorithm can be re-encoded by one of the standard classical evolutionary algorithms such as a binary genetic algorithm. In the current paper we...

When I was appointed Director of California PATH in summer 2003, it was with the specific mandate to help re-structure the research center, to align more closely with the objectives of our main sponsor, Caltrans. The re-organized PATH includes four research programs: Traffic Operations, Transit Operations, Traffic Safety and Policy. The reason for this restructuring was to provide a more direct...