Funding for this research was provided by:
Conselho Nacional de Desenvolvimento Científico e Tecnológico (132249/2014-6)
Text and Data Mining valid from 2018-01-17
Received: 2 March 2017
Accepted: 20 December 2017
First Online: 17 January 2018
: The authors declare that they have no competing interests
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.