Many thanks to Dr. Vicky Hardman for her helpful comments and interesting
discussions. Also to Dr. Lionel Sacks for helping me find such an interesting
project, and for his comments on early versions of this report.
Ditto to my friends and colleagues Notis Stamos and Panos Gevros, who, apart
from their support, made my year in London very enjoyable.
I am also grateful to all my new friends, fellow MSc students and not, we had
some unforgettable moments this year.