SINGAPORE shares started Thursday (Jul 21) on a softer note, despite gains on Wall Street overnight.The Straits Times Index (STI) fell 8.96 points or 0.3 per cent to 3,161.33 as at 9.02 am. Advancers outnumbered decliners 51 to 44, after 41.7 million securities worth S$58 million changed hands.Sembc...