Fidel Castro's failure to meet visiting dignitaries or publish his regular newspaper column has fuelled speculation that his health has deteriorated dramatically. The former president, 82, has not appeared on TV or in print in recent weeks despite expectations that he would participate in the celebrations for the Cuban revolution's 50th anniversary on 1 January. Venezuela's president, Hugo Chavez, an ally and unofficial spokesman, fed the rumour-mill by saying Castro would not surface in public again. "That Fidel in uniform, who walked the streets and towns at daybreak, embracing the people, will not return," Chavez said on TV last Sunday....