Thanks and praise to God, for forgiving my mistakes, for listening to my prayers, for getting me where I stand today, and for taking me to where his kindness, grace and wisdom will guide me. Thanks to my Supervisor Prof. T. Kunz for giving me the chance, for his trust in my capabilities, for his support and guidance throughout the process. Also, Prof. B. Esfandiari who was involved in the project in its early stages, for stimulating the challenge, raising the bar, and providing valuable insights. Thanks to my colleagues and former partners in the lab. and project, A. Cormier and the dear friend S. Echegini whose work, support and discussions since the early stages and later provided great mileage to complete my work. I want also to acknowledge a great initiative from J. Rocamora, a fellow researcher, whose work and information she generously and openly provided were a true milestone to progress in my work. For my "references" in the application process, Prof. Ashraf Elazouni, a friend who really encouraged me to take this step. Prof. Nayer Wanas, one day I was his mentor, we turned to be close friends, then I called him to be my reference. I am so proud of you. .. ! Finally, I want to acknowledge my dear family. They always provided support and affection (my wife), they were always the motivation and inspiration for many milestones in my life (my son Yahya), and for being such a joy and blessing (my son Youssef).