Periodic solutions of Hamiltonian systems with symmetries.- Prescribed energy periodic solutions of Kepler problems with relativistic corrections.- A survey on some existence results for the relativistic pendulum equation.- Recent advances on periodic motions in parallel-plate electrostatic actuators.- Analysis of a mathematical model of competition in a chain of periodic chemostats in series.- Nontrivial solutions of a parameter-dependent Nontrivial solutions of a parameter-dependent.- Branches of forced oscillations for a class of implicit equations involving the -Laplacian.- Atypical bifurcation for a class of delay differential equations.- New elements for a theory of chaos topology.