1. From the Paul Flechsig Institute for Brain Research, Department of Pathophysiology of Neuroglia, University of Leipzig, Leipzig, Germany;
2. the Leibniz Institute for Surface Modification, Leipzig, Germany; and
3. From the Paul Flechsig Institute for Brain Research, Department of Pathophysiology of Neuroglia, University of Leipzig, Leipzig, Germany; the 3Cavendish Laboratory, Department of Physics, University of Cambridge, Cambridge, United Kingdom.