To evaluate the stability of bridge piers affected by the local scouring, the existing formulas for estimating the maximum local scour depth have been developed based on the results of experiments conducted under a constant water level. However, the applicability of these formulas to the cases where the water level rises and falls, such as a water level change in a real river, is not clear. In this study, water flow experiments were conducted on cylindrical and oval bridge pier models to investigate the effect of iterated water level change on the progression of local scour around piers. Results of experiments with cylindrical and oval pier showed that the local scour depth and length increased by an iterated action of the water level change; however, these values converged after the number of iterated actions reached a certain time. The local scour length at upstream of the bridge pier was approximately 1.8 times larger than the theoretical value, which was calculated through the local scour depth and angle of repose in water. The local scour length is an important parameter for defining the streambed protection zone, which is one of the measures against local scour, and we showed that the streambed protection zone needs to be defined more widely.

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QUAD shot is a palliative radiotherapy option that has recently been attracting attention as an effective palliative radiotherapy for patients with head and neck cancer. We report a case in which QUAD shot contributed to the end-of-life care for a patient with locally advanced recurrent oral cancer who had opted against aggressive treatment. A 79-year-old man presented to our department with mandibular pain and trismus. The tumor extended from the tip of the tongue to the lower part of the tongue, and movement disorder of the tongue was observed. The histopathological diagnosis was squamous cell carcinoma. QUAD shot was selected according to the patient' s wishes, and three courses were performed. During the first course, pain control was achieved through the administration of opioid and, at the end, the tumor decreased in size and the pain was alleviated. Thereafter, oral symptoms including pain were controlled and oral function was maintained for about four months from the end of treatment until death. QUAD shot appears to be a useful palliative treatment for reducing pain and maintaining quality of life in patients with locally advanced oral cancer.