1. Politecnico di Milano,Dept. of Mechanical Engineering,Milan,Italy
2. Inst. of Polymers, Composites and Biomaterials, National Research Council,Portici (NA), Lecco,Italy
3. Inst. of Condensed Matter Chemistry and Energy Technology, National Research Council,Lecco,Italy
4. INAIL,Centro Protesi,Vigorso di Budrio (BO),Italy