The U.S. dollar was mostly flat in the upper 159 yen range early Tuesday in Tokyo amid wariness over a possible yen-buying intervention by Japanese authorities after it neared the 160 yen threshold the previous day. At 9 a.m., the dollar fetched 159.70-71 yen compared with 159.52-62 yen in New York and 159.68-70 yen in Tokyo at 5 p.m. Monday. The yen was also weak against the euro, after nearing its record low overnight in New York. The euro was quoted at $1.0732-0733 and 171.39-42 yen against $1.0729-0739 and 171.28-38 yen in New York and $1.0712-0714 and 171.06-10 yen in Tokyo late Monday af…