We introduce a generalized coercivity type condition for set-valued maps defined on topological spaces endowed with a generalized convex structure and we extend the Fan's matching theorem.

We present an extension of Borsuk's antipodal theorem (existence of a zero) for antipodally approachable correspondences without convex values. This result is a generalization of Borsuk-Ulam Theorem and has a fixed-point equivalent formulation.

Nonlinear modified Leslie matrix models with different density-dependent birth and survival rates are analyzed. Conditions for the existence and uniqueness of a positive equilibrium state are discussed. In the case of exponential density dependence the conditions for local stability of a...