This research was supported in part by National Heart, Lung, and Blood Institute Grants R01 HL075515, R15 HL072816-01, and 5F32HL73604-2 and by National Science Foundation Grant MRI-0320865. The computations were performed in part on the National Science Foundation Computing System at the Pittsburgh Supercomputing Center.

This work was performed while the authors were at Hofstra University, Beth Israel Medical Center and Cornell University.