1. Computational Biophysics, German Research School for Simulation Sciences, D-52425 Jülich, Germany,
and Institute for Advanced Simulation, Forschungszentrum Jülich, D-52425 Jülich, Germany
2. Department Farmaco-Chimico, University of Bari “A. Moro”, via Edoardo
Orabona 4, 70125 Bari, Italy
3. Statistical and Biological Physics Sector, Scuola Internazionale Superiore di Studi Avanzati (SISSA), Via Bonomea 265,
I-34136 Trieste, Italy