1. Medical Systems Biophysics and Bioengineering, Leiden Academic Centre for Drug Research, Faculty of Science, Leiden University, Einsteinweg 55, 2333 CC Leiden, The Netherlands
2. Centre for Interdisciplinary Genome Research, Faculty of Science, Leiden University, Einsteinweg 55, 2333 CC Leiden, The Netherlands
3. Department of Physics, Kansas State University, Manhattan, Kansas 66506, United States