“Repulsive/attractive interaction among compact DNA molecules as judged through laser trapping: Difference between linear- and branched-chain polyamines”, Yusuke Kashiwagi, Takashi Nishio, Masatoshi Ichikawa, Chwen-Yang Shew, Naoki Umezawa, Tsunehiko Higuchi, Koichiro Sadakane, Yuko Yoshikawa, Kenichi Yoshikawa, Colloid Polymer Science, in press.