Institute of Computer Science, Foundation for Research and Technology - Hellas, Heraklion, Greece.|Institute of Computer Science, Foundation for Research and Technology - Hellas, Heraklion, Greece.|Unit of Computational Medicine, Department of Medicine, Karolinska Institutet, 171 77, Stockholm, Sweden.|Unit of Computational Medicine, Department of Medicine, Karolinska Institutet, 171 77, Stockholm, Sweden.|Institute of Computer Science, Foundation for Research and Technology - Hellas, Heraklion, Greece. tsamard@csd.uoc.gr.