This colloquium, convened by Yuri Murano, was held on Saturday 11 June 2011 at Trinity College. Speakers were Javier Arce (Université Charles de Gaulle, Lille III), Andrea Augenti (Università di Bologna a Ravenna), Franzo Alto Bauer (Ludwig-Maximilians Universität, München), Anna Leone (Durham University), Cyril Mango and Marlia Mundell Mango (Oxford), and Yuri Marano (Università degli Studi di Padova). More