**Acknowledgments**

I would like to sincerely thank all the authors for their remarkable contribution to this book, the peer reviewers for their time and constructive spirit, and José A. Sánchez-Zapata for critically reviewing the Preface and Introduction. Also, I wish to thank the staff members at the MDPI editorial office for their dedicated support. Finally, I'm grateful to the Spanish Ministries concerned with science and EU ERDF funds for funding my research contract RYC-2015-19231 and project CGL2017- 89905-R.

**Dedication:** To my mother, to her trusting and serene gaze.
