1. Department of Mathematics, University of Padua, 35122 Padova, Italy
2. Department of Neurosciences, Imaging and Clinical Sciences, University of Chieti-Pescara, 66100 Chieti, Italy
3. Center for Advanced Studies and Technology (C.A.S.T.), University of Chieti-Pescara, 66100 Chieti, Italy
4. Department of Health Sciences, University of Florence, 50121 Firenze, Italy