Funding for this research was provided by:
Deutsche Forschungsgemeinschaft (BR1873/9-1)
Text and Data Mining valid from 2018-11-20
Received: 17 April 2018
Accepted: 1 November 2018
First Online: 20 November 2018
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: In compliance with the Helsinki Declaration and in accord with the statements given by the local ethics committee of the University of Regensburg, ethics approval and informed consent was not required for this study.
: Not applicable.
: The authors declare that they have no competing interests.
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