1. Paul Scherrer Institute, 5232 Villigen, Switzerland
2. Department of Health Sciences and Technology, ETH Zürich, 8092 Zürich, Switzerland
3. Laboratory for Cellulose and Wood Materials, Empa Swiss Federal Laboratories for Materials Science and Technology, 8600 Dübendorf, Switzerland
4. Department of Materials Science, University of Milano-Bicocca, 20126 Milano, Italy