Funding for this research was provided by:
Deutsche Forschungsgemeinschaft (DE 2680/3–1)
Received: 17 January 2020
Accepted: 12 June 2020
First Online: 22 June 2020
Ethics approval and consent to participate
: The study was approved by the ethics commission of the Technical University of Munich (155/16 S) and the Ministry of culture and education of the state of Bavaria in Germany.Students did not participate if they had not provided a consent form signed by them and their parents before.
: Not applicable.
: The authors declare that they have no competing interests.