This volume of the International School of Physics Enrico Fermi is dedicated to Valerio Filippini. He devoted his life to physics. Valerio Filippini was born in Somma Lombardo (Milano) on December 8, 1958. He obtained the Master Degree in Physics at the University of Pavia in 1982, cum laude. After a working parenthesis at an industrial firm, he became Research Physicist of INFN, Sezione di Pavia, in 1988 and was promoted Senior Research Physicist in 1993. He participated to the experiments PS 179 (TOFRADUPP) and PS 201 (Obelix) at LEAR (CERN), FINUDA at LNF and ATHENA at AD (CERN). His outsta.