1. Department of Computer Science and Engineering, University of Connecticut, Storrs, Connecticut, USA.
2. Computer Science and Artificial Intelligence Lab, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA.
3. Department of Mathematics, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA.
4. Department of Computer Science, Harvey Mudd College, Claremont, California, USA.
5. The Institute for Systems Genomics, University of Connecticut, Storrs, Connecticut, USA.