Asia markets move cautiously ahead of bank meetings

Tokyo stocks sank on a strong yen as traders await central bank meetings in Japan and the United States this week, while other Asian markets fluctuated following a negative lead from Wall Street. Promises of monetary easing after last month's shock British EU exit vote led a surge in shares -- and record highs on Wall Street -- but a degree of nervousness has set in as two of the biggest central banks prepare to meet. The Federal Reserve concludes its gathering Wednesday and although it is not e