TOKYO -- Nissan Motor denied a request from top shareholder Renault to convene an extraordinary shareholders meeting to appoint a replacement for ousted Chairman Carlos Ghosn, a move that could intensify a power struggle over the Japanese automaker's management. Instead, Nissan formed an independent governance committee during a board meeting held Monday, tasked with reviewing the weak governance structure at Nissan -- which allowed one figure, Ghosn, to hold overwhelming power -- and devising a process to decide executive pay.