Funding for this research was provided by:
Deutsche Forschungsgemeinschaft (KU2760/4-1)
Received: 29 November 2018
Accepted: 6 May 2019
First Online: 28 May 2019
Ethics approval and consent to participate
: The study was approved by the Regierung von Unterfranken (files 55.2-2531.01- 114/13, 55.2-2531.01-118/13, and 55.2-2531.01-91/14).
: Not applicable
: The authors declare that they have no competing interests.
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