Funding for this research was provided by:
Technische Universität Dresden (L-00046-512-518-1050202)
Received: 24 May 2020
Accepted: 6 October 2020
First Online: 23 October 2020
Ethics approval and consent to participate
: The Ethics Committee Office of Kimpa Vita University in Uíge had unanimously approved that the study is in according with the standards and regulations established by the committee of the institution.
: Not applicable.
: The authors declare that they have no competing interests.