This work is dedicated to my lovely family, mi wife Katherine Vasquez, my daughter Natalia Sobrevilla, my mother Angela Cabezudo, my sister Mayra Sobrevilla, my mamita Victoria Carrizales, and my uncle Cesar Cabezudo. Besides, I dedicate this work to all future PhD students who feel they have lost their way along their own research. You will arrive at the correct place, be patient and keep researching!To my life partner, my wife and my best friend, Katherine Vasquez, who supported me unconditionally all this time. You resisted so many work nights and times in which, despite being present, I was a bit absent. I also would like to thank my beautiful daughter, Natalia, you are the best thing that happened to me, and you have been my impulse to give the best of me in this last period.To my family who, despite the distance, were always with me encouraging me on this long walk (and asking every day: "Are you going to finish your thesis soon?"). To my mom Angela Cabezudo, my sister Mayra Sobrevilla, my "mamita" Victoria Carrizales, my uncle Cesar Cabezudo, my dad Mauro Sobrevilla and Iván Ferrer. You are the best family I could have had.To my advisor, prof. Dr. Thiago Alexandre Salgueiro Pardo, for the guidance, the learning acquired, his good cheer and patience. For cheering me up when I felt lost and accepting me again as his student after the master :)To my friends from the Methodist Church in São Carlos because they have been my family during these years. I want to thank the pastors, Levi Pereira, Gilson Sales and Nuria Lisboa and the members of the church :). In particular, I would also like to thank José Mendoza,