First of all, I am deeply grateful to my parents, Irene and Judivan, for all their support. Although they did not attend high school and had to start working young to help support their households, they were always aware of the value of education and the countless doors it opens up. Thanks to this deep belief, they always encouraged me to study hard and, without their support, I would not be able to be where I am right now.I am also glad to have met so many amazing people during my journey at PUC-Rio. Pursuing a Master's degree during a pandemic was not easy, but, even in the toughest moments, I always knew that I could count on my dearest friends. I thank them, especially Pedro, for all the moments we have shared together.Finally, I would like to thank my advisor, Prof. Ricardo Dahis, for his guidance and for being so considerate during the making of this thesis. I also thank Prof. Juliano Assunção and Prof. Francisco Costa for their valuable comments. Any mistakes are my own.This study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior -Brasil (CAPES) -Finance Code 001. The financial support from PUC-Rio is gratefully acknowledged.