The relationships were examined between the relative force level and exertion strategy during rapid isometric contractions. Thirteen subjects exerted isometric pinchings as fast as possible at various force levels. Force curves and surface EMGs from the first dorsal interosseous muscle were obtained during the contractions. While the single-peaked force curves remained analogous up to a certain force level, they changed to multi-peaked ones at higher force levels. The critical force level, which could be determined in all subjects as relative force level to MVC, was positively correlated with the %MVC EMG magnitude for unit time, obtained below the critical level. EMG durations were significantly shorter blow than above the critical level. These results suggest that different exertion strategies are utilized in rapid contractions at different force levels, and that individual differences in the critical force level are related to difference in the manner of motor unit activation.

1)We reproduced a problem–based learning (PBL) tutorial at our school and developed our own PBL tutorial, which we call "Fujita–style PBL." This is a clinical problem-solving type of PBL, in which both a monitoring room and small–group learning rooms are used.
2)To maintain the present number of PBL lessons despite the limited number of tutors, one tutor supervises several groups simultaneously. Coordinators observe the progress of PBL from a monitoring room and support the tutors.
3)Students learn the given scenario and identify their learning issues. After they study the learning issues by themselves, the students return to tutorials to explain their learning issues. Thereafter, each group's findings are presented to the groups supervised by one tutor.

Background/Aims: Image-enhanced endoscopy can detect superficial oro-hypopharyngeal squamous cell carcinoma; however, reliable endoscopy of the pharyngeal region is challenging. Endoscopy under general anesthesia during transoral surgery occasionally reveals multiple synchronous lesions that remained undetected on preoperative endoscopy. Therefore, we aimed to determine the lesion detection capability of endoscopy under general anesthesia for superficial oro-hypopharyngeal squamous cell carcinoma. Methods: This retrospective study included 63 patients who underwent transoral surgery for superficial oropharyngeal squamous cell carcinoma between April 2005 and December 2020. The primary endpoint was to compare the lesion detection capabilities of preoperative endoscopy and endoscopy under general anesthesia. Other endpoints included the comparison of clinicopathological findings between lesions detected using preoperative endoscopy and those newly detected using endoscopy under general anesthesia. Results: Fifty-eight patients (85 lesions) were analyzed. The mean number of lesions per patient detected was 1.17 for preoperative endoscopy and 1.47 for endoscopy under general anesthesia. Endoscopy under general anesthesia helped detect more lesions than preoperative endoscopy did (p<0.001). The lesions that were newly detected on endoscopy under general anesthesia were small and characterized by few changes in color and surface ruggedness. Conclusions Endoscopy under general anesthesia for superficial squamous cell carcinoma is helpful for detecting multiple synchronous lesions.