publication of the papers, Obokata "was hailed as a bright new star in the scientific firmament and a national hero." STAP cell controversy Within days of publication of the Nature articles, "disturbing allegations emerged [...] images looked doctored, and chunks of [...] text were lifted from other papers." Critics noted that images in the published articles were similar to those published in Obokata's doctoral thesis, the latter involving different experiments than those presented in the Nature publications. In 2014 Riken launched an investigation into the issue, and announced on April 1 that Obokata was guilty of scientific misconduct on two of the six charges initially brought against her. The Riken investigation document reported: Obokata apologised for her "insufficient efforts, ill-preparedness and unskillfulness", and claimed she had only made "benevolent mistakes"; she denied the charge that she had fabricated results, and denied that she lacked ethics, integrity, and humility. Obokata also reported that her STAP cells existed. The Guardian reported that although Obokata's collaborators initially supported her, "one by one they relented and asked Nature to retract the articles." In June 2014, Obokata agreed to retract both papers. Near the time of retraction, "genetic analysis showed that the Stap cells didn’t match the mice from which they supposedly came." Although Obokata claimed not to know how this was possible, "the obvious, and rather depressing, explanation is that her so-called Stap cells were just regular embryonic stem cells that someone had taken from a freezer and relabelled." In July 2014, Obokata participated, with monitoring by a third party, in Riken's effort to experimentally reproduce the original STAP cell findings. Those efforts failed to replicate the results originally reported. Although cleared of misconduct Sasai was criticized for inadequate supervision of Obokata, and he described himself as "overwhelmed with shame". After spending a month in hospital, Sasai took his own life on August 5, 2014. Obokata resigned from Riken in December 2014. In a February 2015 article, The Guardian reported that Obokata was guilty of "unbelievable carelessness", having "manipulated images and plagiarised text." Obokata was also described as exhibiting hubris: "If Obokata hadn’t tried to be a world-beater, chances are her sleights of hand would have gone unnoticed and she would still be looking forward to a long and happy career in science. [...] By stepping into the limelight, she exposed her work to greater scrutiny than it could bear." In 2016, Obokata's book