Department of Mathematics, University of California, Irvine, Irvine, California, United States of America.|Department of Molecular Biology and Biochemistry, Cancer Research Institute, University of California, Irvine, Irvine, California, United States of America.|Department of Molecular Biology and Biochemistry, Cancer Research Institute, University of California, Irvine, Irvine, California, United States of America.|Department of Mathematics, University of California, Irvine, Irvine, California, United States of America.