Supersymmetry of the Nonstationary Schr\"odinger equation and Time-Dependent Exactly Solvable Quantum Models

New exactly solvable quantum models are obtained with the help of the supersymmetric extencion of the nonstationary Schr/"odinger equation.Comment: Talk at the 8th International Conference "Symmetry Methods in Physics". Dubna, Russia, 28 July - 2 August, 199

Higher Order Matrix SUSY Transformations in Two-Dimensional Quantum Mechanics

The iteration procedure of supersymmetric transformations for the two-dimensional Schroedinger operator is implemented by means of the matrix form of factorization in terms of matrix 2x2 supercharges. Two different types of iterations are investigated in detail. The particular case of diagonal initial Hamiltonian is considered, and the existence of solutions is demonstrated. Explicit examples illustrate the construction.Comment: 15

Demonstration of antigenic differences between strains of poliovirus type 1 by agar diffusion precipitation reaction.

Antigenic differences between type 1 poliovirus strains circulating in nature were investigated by agar diffusion precipitation reaction. Three strain-specific sera were absorbed with antigens prepared from 8 strains (Sabin's vaccine strain LSc2ab and 7 strains isolated from poliomyelitis patients or healthy persons). The results suggested the presence of at least 5 antigenic determinants in the poliovirus type 1 strains studied. Three determinants in different combinations were found in 7 strains and 2 determinants were found in 1 strain. It is assumed that antigenic differences among poliovirus strains may be due to different combinations of several antigenic determinants