Blind capoeira teacher Joao Kanoa jokes with one of his students after giving classes at his home at the Fallet slum, in Rio de Janeiro March 2, 2013. Kanoa says he lost his vision at work seventeen years ago when the change of temperature inside a cold-storage room damaged his retina. Picture taken March 2, 2013. REUTERS/Pilar Olivares (BRAZIL - Tags: SOCIETY)