Complex sentence: At the end of 2013, Pickard retired from full-time NHS practice and head of academic neurosurgery, but remained active in research as a voluntary director of research in the University of Cambridge.
Split into simpler sentences: At the end of 2013, Pickard retired from full-time NHS practice and Head of Academic Neurosurgery. He remains active in research as a Voluntary Director of Research in the University of Cambridge.