Universality classes of Ising-like phase transitions are investigated in a series of two-dimensional synchronously updated probabilistic cellular automata (PCAs), whose time evolution rules are either of Glauber type or of majority-vote type, and degrees of anisotropy are varied. Although early works showed that coupled map lattices and PCAs with synchronously updating rules belong to a univers...

In this study various electrical conductivity approximations used in bidomain models of cardiac tissue are considered. Comparisons are based on epicardial surface potential distributions arising from regions of subendocardial ischaemia situated within the cardiac tissue. Approximations studied are a single conductivity bidomain model, an isotropic bidomain model and equal and reciprocal anisotr...

primary assumption in most problems of elasticity theory in petroleum geophysics is that the elastic media is isotropic. laboratory experiments confirmed that most rocks are anisotropic. if in one medium, properties vary with directions, it is named as anisotropic. knowledge about anisotropy reduces risk and cost of hydrocarbon production. in the present study, anisotropy of a carbonate reservo...

The in-plane optical anisotropy which comes from the heavy-hole and the light-hole transitions in InAs submonolayers inserted in a ~311!-oriented GaAs matrix is studied by reflectance-difference spectroscopy ~RDS!. The steplike density of states obtained from RDS demonstrates that the ultrathin InAs layers should be regarded as two-dimensional quantum wells rather than isolated clusters, even f...

Structural and functional cardiac anisotropy varies with the development, location, and pathophysiology in the heart. The goal of this study was to design a cell culture model system in which the degree, change in fiber direction, and discontinuity of anisotropy can be controlled over centimeter-size length scales. Neonatal rat ventricular myocytes were cultured on fibronectin on 20-mm diameter...

We have extended our "coupling clamp" technique, in which we couple a real cell to a real-time simulation of a model cell, to now incorporate a real cardiac cell as the central element of a two-dimensional sheet of model cells, in which the coupling conductances may be different in the x and y directions and a specific region of lack of coupling conductance may serve as a resistive barrier. We ...

Performance of three-dot bisection was determined as a function of orientation for a variety of feature separations and field meridians at eccentricities of 0-10 deg for two observers. The dot stimuli and separations were scaled in size to compensate for eccentricity. The precision of three-dot bisection was found to depend on the direction of test-feature offset. In the fovea, horizontal and v...

We report the detailed structural characterization and magnetic investigation of nanocrystalline zinc ferrite nanoparticles supported on a silica aerogel porous matrix which differ in size (in the range 4-11 nm) and the inversion degree (from 0.4 to 0.2) as compared to bulk zinc ferrite which has a normal spinel structure. The samples were investigated by zero-field-cooling-field-cooling, therm...