Center for Bioinformatics, University of Pennsylvania, Philadelphia, PA 19104, USA. manduchi@pcbi.upenn.edu|Center for Bioinformatics, University of Pennsylvania, Philadelphia, PA 19104, USA. manduchi@pcbi.upenn.edu|Center for Bioinformatics, University of Pennsylvania, Philadelphia, PA 19104, USA. manduchi@pcbi.upenn.edu|Center for Bioinformatics, University of Pennsylvania, Philadelphia, PA 19104, USA. manduchi@pcbi.upenn.edu|Center for Bioinformatics, University of Pennsylvania, Philadelphia, PA 19104, USA. manduchi@pcbi.upenn.edu|Center for Bioinformatics, University of Pennsylvania, Philadelphia, PA 19104, USA. manduchi@pcbi.upenn.edu