Funding for this research was provided by:
Fundação para a Ciência e a Tecnologia (IF/01354/2015)
Text and Data Mining valid from 2019-07-10
Received: 8 April 2019
Accepted: 1 July 2019
First Online: 10 July 2019
Compliance with Ethical Standards
: The author reports no real or perceived vested interests that relate to this article that could be construed as a conflict of interest.