1. Institute of Clinical Physiology; National Research Council; Pisa Italy
2. Fondazione G. Monasterio CNR; Regione Toscana; Pisa Italy
3. GE Healthcare Park Alle 295, Broendby; Denmark
4. Department of Electrical Engineering; The Technical University of Denmark; Lyngby Denmark
5. Laboratory of Medical Science, Institute of Life Sciences; Scuola Superiore Sant'Anna; Pisa Italy
6. Department of Information Engineering: EIT; University of Pisa; Pisa Italy