Received: 14 May 2018
Accepted: 23 January 2019
First Online: 31 January 2019
Ethics approval and consent to participate
: The present study was approved by the Ethics Committee of the Technische Universität Dresden, Germany (EK232062011), and only individuals who provided written informed consent were included as study participants.
: Not applicable.
: The authors declare that they have no competing interests.
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