Department of Computer Science, ETH Zurich, Zurich, Switzerland.|Department of Computer Science, ETH Zurich, Zurich, Switzerland.|Department of Computer Science, ETH Zurich, Zurich, Switzerland.|Brown Center for Biomedical Informatics, Brown University, Providence, RI, USA.|Department of Computer Science, ETH Zurich, Zurich, Switzerland.|Department of Computer Science, ETH Zurich, Zurich, Switzerland.