The volatile Senex at the Bombay Stock Exchange closed 41 points up at 16,918 in its last session of the day.Earlier, the 30-share barometer gained 73 points to 16,950 in opening trade today morning on fresh buying by funds and retail investors at prevailing lower levels. Later, after briefly slipping into the red in very volatile trade, Sensex recovered again and stood 51 points, in positive territory, at 16,928 in afternoon deals before closing 41 points up at 16,918.In a Similar fashion, the wide-based National Stock Exchange index Nifty also moved 10 points up to over 5,128 in its closing session