Harrison's spiritual soft rock, meanwhile, had gone out of fashion and, for much of the next decade, he concentrated on a new career as a producer with Handmade Films, the company he had formed in 1979 with Dennis O'Brien.
In March 1922, Prokofiev moved with his mother to the town of Ettal in the Bavarian Alps, where for over a year he concentrated on an opera project, The Fiery Angel, based on the novel by Valery Bryusov.
"My mummy says 'no go to French school'," said one serious-faced boy as he concentrated on a subtraction sum.
Mostly, Rayas told me, he concentrated on a string of anonymous phone calls that started after he went on television to ask for help in finding his daughter.
He concentrated to a greater extent on batting for longer periods; many critics, including Hobbs himself, recognised the change and suggested that he was a better batsman before 1914.
After providing a short historical overview ranging from the first monoclonal antibodies to recombinant antibodies and synthetic antibodies, he concentrated on a class of molecules - called DARPins (designed ankyrin repeat proteins) - that may substitute antibodies.
After briefly studying painting in Madrid, he concentrated on an acting career.
Instead, he concentrated on an ambitious cycle of paintings called "The Bathers", known also as "The Sid Women", an erotic vision of paradise.
I modelled how to use the secateurs safely and he concentrated for an hour cutting the twigs into lengths; through estimating and careful cutting they were all, pretty much, equal length.
He left that to other people while he concentrated on creating a record that would withstand scrutiny.
