著者
Yoshiyuki Kojima Susumu Yokoya Noriaki Kurita Takayuki Idaka Tetsuo Ishikawa Hideaki Tanaka Yoshiko Ezawa Hitoshi Ohto
出版者
THE FUKUSHIMA SOCIETY OF MEDICAL SCIENCE
雑誌
FUKUSHIMA JOURNAL OF MEDICAL SCIENCE (ISSN:00162590)
巻号頁・発行日
vol.65, no.3, pp.76-98, 2019 (Released:2020-01-09)
参考文献数
116
被引用文献数
9

Cryptorchidism (undescended testes) is among the most common congenital diseases in male children. Although many factors have been linked to the incidence of cryptorchidism, and testicular androgen plays a key role in its pathogenesis, the cause remains unknown in most cases. Recently, a Japanese group published a speculative paper entitled, “Nationwide increase in cryptorchidism after the Fukushima nuclear accident.” Although the authors implicated radionuclides emitted from the Fukushima accident as contributing to an increased incidence of cryptorchidism, they failed to establish biological plausibility for their hypothesis, and glossed over an abundance of evidence and expert opinion to the contrary. We assessed the adequacy of their study in terms of design setting, data analysis, and its conclusion from various perspectives. Numerous factors must be considered, including genetic, environmental, maternal/fetal, and social factors associated with the reporting of cryptorchidism. Other investigators have established that the doses of external and internal radiation exposure in both Fukushima prefecture and the whole of Japan after the accident are too low to affect testicular descent during fetal periods;thus, a putative association can be theoretically and empirically rejected. Alternative explanations exist for the reported estimates of increased cryptorchidism surgeries in the years following Japan’s 2011 earthquake, tsunami, and nuclear crisis. Data from independent sources cast doubt on the extent to which cryptorchidism increased, if at all. In any case, evidence that radionuclides from the Fukushima Daiichi Nuclear Power Plant could cause cryptorchidism is lacking.
著者
Kazuhide YASHIRO Yoshiyuki KOJIMA Mitsuru SHIMIZU
出版者
Railway Technical Research Institute
雑誌
Quarterly Report of RTRI (ISSN:00339008)
巻号頁・発行日
vol.48, no.3, pp.136-141, 2007 (Released:2007-10-16)
参考文献数
1
被引用文献数
21 96

Since mountain tunnels are generally surrounded by stable ground, their displacement during seismic activity tends to be minimized, making such structures less susceptible to seismic damage. Despite this, many railway mountain tunnels have sustained damage, from the 1923 Kanto Earthquake to the 2004 Niigataken-Chuetsu Earthquake. This paper provides an outline of the historical damage to mountain tunnels in Japan and outlines the results of case studies on damage sustained in mountain tunnels. Also outlined here is a classification of the damage patterns and the conditions of damage based on the results of the case studies, and we refer to the estimated causes of damage to tunnels in the 2004 Niigataken-Chuetsu-Earthquake.