Hisao Honda has been a Guest Professor at the Graduate School of Medicine, Kobe University, Japan since 2012. He is an Emeritus Professor of Hyogo University, Kakogawa, Japan. His research interests include theoretical biology, especially morphogenesis of multicellular organisms and branching structures. He received his PhD from Kyoto University in 1973. He worked as a Researcher, Senior Researcher and Chief Researcher at Kanebo Institute for Cancer Research, Kobe and Osaka (1975-1996) and a Professor at Hyogo University (1996-2013), prior to joining the Graduate School of Medicine, Kobe University.Tatsuzo Nagai had been a Professor at Kyushu Kyoritsu University, Kitakyushu, Japan between 1981 and 2008. He has been an Emeritus Professor at Kyushu Kyoritsu University since 2009. His research interests include statistical physics, especially dynamical interfacial systems, i.e., soap froths, grain aggregates and biological cell aggregates. He received his PhD from Kyushu University, Fukuoka, Japan in 1972. He worked as an associate Professor at Kyushu Kyoritsu University from 1973, prior to being a Professor.