1Faculty of Biochemistry and Molecular Medicine, University of Oulu, 90220 Oulu, Finland
2Department of Physics, Tampere University of Technology, 33720 Tampere, Finland
3Department of Biomedicine, University of Bergen, 5020 Bergen, Norway
4Division of Psychiatry, Haukeland University Hospital, 5021 Bergen, Norway
5Department of Sustainable Chemistry, Technical Faculty, University of Oulu, 90570 Oulu, Finland
6Biocenter Oulu, University of Oulu, 90220 Oulu, Finland
7Department of Physics, University of Helsinki, 00560 Helsinki, Finland
© The Author(s) 2017
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