Preface.- Lower bounds for sojourn time in a simple shape resonance model.- Spectral properties for Hamiltonians of weak interactions.- Magnetic Laplacian in sharp three-dimensional cones.- Spectral clusters for magnetic exterior problems.- The spectral shift function and the Witten index.- Stahl's theorem (aka BMV conjecture): insights and intuition on its proof.- Some estimates regarding integrated density of states for random Schrödingeroperator with decaying random potentials.- Boundary values of resolvents of self-adjoint operators in Krein spaces and applications to the Klein-Gordon equation.- Levinson's theorem: an index theorem in scattering theory.- Counting function of magnetic resonances for non-definite sign perturbations.- Harmonic analysis and random Schrödinger operators.