Throughout our lives, no matter what we do, we certainly wouldn't be able to do it without the effective participation of a significant number of people. The act of remembering these people at this time is a way of expressing my gratitude and thanking them for all the help they have given me in producing this research and completing this dissertation.

So in this simple but sincere gesture, I would like to say thank you: I would like to thank God for the opportunities I have been given in life, especially for having protected me during the more than 24,000 kilometers I have traveled during this master's degree, for having met people who have only made me greater as a human being, but I would also like to thank him for having given me difficult moments, situations that have been fundamental as an example of learning and a reason to test my faith. To my parents, especially my mother Francisca Ilma, because I don't know what I would be without her upbringing and because she is a beautiful living example of a human being, of character and honesty.

She always made me believe that I could be the best. I love you unconditionally, my mother.

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