Nikkei opened 0.28 percent lower on Monday, despite an improved Bank of Japan\'s quarterly Tankan survey on corporate sentiment for March. At 9:15 a.m., the 225-issue Nikkei Stock Average was down 35.17 points, or 0.28 percent, from Friday to 12,362.74. The broader Topix index of all First Section issues on the Tokyo Stock Exchange was down 6.80 points, or 0.66 percent, at 1, 027.91.