Ribbon-moves for 2-knots with 1-handles attached and Khovanov-Jacobsson   numbers
  We prove that a crossing change along a double point circle on a 2-knot is realized by ribbon-moves for a knotted torus obtained from the 2-knot by attaching a 1-handle. It follows that any 2-knots for which the crossing change is an unknotting operation, such as ribbon 2-knots and twist-spun knots, have trivial Khovanov-Jacobsson number. 
J. Scott Carter (University of South Alabama), Masahico Saito   (University of South Florida), Shin Satoh (Chiba University)