A change-of-variable formula with local time on surfaces 1 Blow-down 1 Brownian motion 1 Controllability of linear and nonlinear PDE’s 1 Excitable system 1 Filtering estimate 1 Free boundary problem 1 Free-boundary problem 1 Hidden markov chain 1 Improvement of flatness 1 Innovation process 1 Nash equilibria 1 One-phase free boundary problem 1 Optimal stopping problem 1 Perpetual American options 1 Random dividends 1 Reaction-interface system 1 Singular limit 1 Weak solutions 1 bi-objective optimal control problems 1 control of free-boundary problems 1 numerical methods 1