Funding for this research was provided by:
Bundesministerium für Bildung und Forschung (BMBF-FK 01 GY 1610)
Received: 19 December 2017
Accepted: 22 January 2018
First Online: 30 January 2018
Ethics approval and consent to participate
: Ethics approval was granted by the ethics committee of Hannover Medical School on 14th February 2017 (Registration N° 7260).
: Not applicable
: The authors declare that they have no competing interests.
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