The Sensex at the Bombay Stock Exchange fell 34 points, or 0.2 per cent, to 15,937 in the first few minutes of trade this morning on profit-booking by investors.Later, the Sensex remained weak and stood 60 points or 0.4 percent in the negative zone, at 15,911 in afternoon deals a short while ago. But following the news that the output of key infrastructure sectors grew 6.8 per cent in November limited the losses.Other Asian markets in Japan, China, South Korea and Taiwan were down by between 0.1 per cent and 0.8 per cent.