Biological Physics Group, School of Physics and Astronomy, University of Manchester, Manchester, United Kingdom.|Biological Physics Group, School of Physics and Astronomy, University of Manchester, Manchester, United Kingdom.|Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.|Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.|Biological Physics Group, School of Physics and Astronomy, University of Manchester, Manchester, United Kingdom.