RESUMO
In quantum chemical calculations, there are two facts of particular relevance: the position-dependent mass Schrödinger equation (PDMSE) and the exponential-type potentials used in the theoretical study of vibrational properties for diatomic molecules. Accordingly, in this work, the treatment of exactly solvable PDMSE for exponential-type potentials is presented. The proposal is based on the exactly solvable constant mass Schrödinger equation (CMSE) for a class of multiparameter exponential-type potentials, adapted to the position-dependent-mass (PDM) kinetic energy operator in the O von Roos formulation. As a useful application, we consider a PDM distribution of the form [Formula: see text], where the different parameters can be adjusted depending on the potential under study. The principal advantage of the method is that solution of different specific PDM exponential potential models are obtained as particular cases from the proposal by means of a simple choice of the involved exponential parameters. This means that is not necessary resort to specialized methods for solving second-order differential equations as usually done for each specific potential. Also, the usefulness of our results is shown with the calculation of s-waves scattering cross-section for the Hulthén potential although this kind of study can be extended to other specific potential models such as PDM deformed potentials.
RESUMO
In this work, a scheme to generate exact wave functions and eigenvalues for the spherically symmetric three-dimensional position-dependent effective mass Schrödinger equation is presented. The methodology is implemented by means of separation of variables and point canonical transformations that allow to recognize a radial dependent equation with important differences as compared with the one-dimensional position dependent mass problem, which has been widely studied. This situation deserves to consider the boundary conditions of the emergent problem. To obtain specific exact solutions, the methodology requires known solutions of ordinary one-dimensional Schrödinger equations. We have preferred those applications that use the harmonic oscillator and the Morse oscillator solutions.
RESUMO
En el Hospital "Luis Catelaro Ayala", del IMSS en un periodo de un año se operaron 176 pacientes con el procedimiento de Pereyra modificado; 70 casos llevan seis o más meses se seguimiento y el resultado ha sido bueno en 67 de ellos. La operación se efectuó en 160 pacientes sin cirugía previa y en 16 casos con operación previa para corrección de la Incontinencia Urinaria de Esfuerzo; se obtuvieron complicaciones en 32 casos (18%) correspondiendo la mayoría de ellas a retención de orina o infección de vías urinarias. Se presentaron dos casos de lesión vesical. Se describe método de selección para la técnica, criterio de seguimiento y se reseña brevemente el procedimiento según con los lineamientos generales señalados por los autores
