The Keio Twin Research Center (KoTReC) was established in 2009 at Keio University to combine two longitudinal cohort projects — the Keio Twin Study (KTS) for adolescence and adulthood and the Tokyo Twin Cohort Project (ToTCoP) for infancy and childhood. KoTReC also conducted a two-time panel study of self-control and psychopathology in twin adolescence in 2012 and 2013 and three independent anonymous cross-sectional twin surveys (ToTcross) before 2012 — the ToTCross, the Junior and Senior High School Survey and the High School Survey. This article introduces the recent research designs of KoTReC and its publications.

We have fabricated pentacene field-effect transistors (FETs) on polyimide-sheet films with polyimide gate dielectric layers and parylene encapsulation layer, and investigated the high-temperature performance. It is found that the mobility of encapsulated FETs is enhanced from 0.5 to 0.8 cm2/Vs when the device is heated from room temperature to 160°C under light-shielding nitrogen environment. Furthermore, after the removal of annealing temperatures up to 160°C, the transistor characteristic of mobility and on/off current ratio show no significant changes, demonstration the excellent thermal stability of the present organic FETs.