How to synthesize all the acknowledgments to so many people in a few words? It is true that no man is an island and all efforts that I had to complete this work would not be possible without some form of help from many people. I would like to say thank you very much to the all the attention, dedication, understanding of my promotors, Prof. Dr. Maria Tereza Silveira Böhme and Professor Dr. Veerle De Bosscher. Without you, nothing would be possible. Thanks to my Family, for the support that they always gave to me in all my achievements. Thank you to my friends, which stay with me in the good and bad times,