Stability results for a reaction-diffusion problem with mixed boundary conditions and applications to some symmetric cases

In this article we consider a one-dimensional reaction-diffusion problem with mixed boundary conditions. We provide conditions for the existence or nonexistence of stable nonconstant solutions whose derivative vanishes at some point. As an application, we obtain similar results for problems with Dirichlet boundary conditions posed in some symmetric domains: an n-dimensional ball, surfaces of revolution, and model manifolds.