The Sensex at the Bombay Stock Exchange fell 49 points, or 0.3 per cent, to 15,890, in early trade, today, as investors booked profits after a two-session rally.Later, after moving in and out of the positive zone, in volatile trade, the Sensex stood 38 points, or 0.2 percent in negative territory, at 15,901 in afternoon deals, a short while ago.Other Asian markets in Japan, China, Hong Kong, South Korea, Singapore, and Taiwan were trading mixed, today.But over on Wall Street, the Dow Jones Industrial Average had jumped 1.5 per cent, overnight