2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/21491A nonmonotonic dependence of the differential resistance of the first step of a phase-slip line on the heat-reservoir temperature near Tc has been observed experimentally for the first time in a superconducting tin film. This behavior is interpreted as a conversion of the phase-slip line into an elementary resistive domain as the result of a deviation from the isothermal conditions.3 pages, 3 figures, RevTex4. Present address of the first author addedSuperconductivityMesoscale and Nanoscale Physicstext