RESUMO
The algebraic formula of the backscattering coefficient has been derived within the scope of the physical optics method. The formula relates the lidar return anomalous high amplitude of observed experimentally with the principal parameters of a polydisperse crystalline medium. It is shown that at the lidar small-angular scanning relative to the normal to the ice-plate preferred orientation, the average size of the plate can be defined and the flutter size can be evaluated from the behavior of the lidar return variation.
RESUMO
The relationships for the backscattering cross sections are derived within the scope of the physical-optics method for the case in which polarized optical radiation interacts with an oriented semitransparent circular plate. Theoretical investigation of the depolarization relation is carried out for the polarization signal backscattered from a set of oriented circular plates. An algorithm is suggested for the calculation of the orientation angles of the plates in the scattering volume.
RESUMO
Recent reports have suggested that repetitive transcranial magnetic stimulation (rTMS) is effective in major depression. Unlike ECT, rTMS does not involve a seizure and is associated with minimal side-effects, including cognitive difficulties. However, the effect of rTMS on cognitive functioning has not been systematically evaluated. This study was designed to examine the neuropsychological effects of slow rTMS in normal volunteers. Forty-six normal volunteers were randomly assigned to receive one session of right (N = 16) or left prefrontal (N = 15), or sham (N = 15) rTMS at 1 HZ. Patients were assessed before and after stimulation by a computerized neurospychological battery. All three groups showed significant improvement over time in processing speed (reaction time) and efficiency (correct responses per unit of time). However, no time by group interaction was found for any of the neuropsychological tests. These findings suggest that a single session of slow rTMS does not interfere with neurospychological functioning in normal volunteers, supporting clinical reports of no adverse cognitive effects.