@inproceedings{oai:jaxa.repo.nii.ac.jp:00013917,
 author = {村上, 彰 and 高橋, 景一 and 右藤, 文彦 and 堀口, 弘子 and 吉村, 建二郎 and Murakami, Akira and Takahashi, Keiichi and Uto, Norihiko and Horiguchi, Hiroko and Yoshimura, Kenjiro},
 book = {宇宙利用シンポジウム　第19回　平成14年度, Space Utilization Research: Proceedings of the Nineteenth Space Utilization Symposium},
 month = {Feb},
 note = {The effects of short-term microgravity on the swimming behavior of Paramecium have been studied using a drop tower, which provides a transitional phase of low gravity before starting the free fall. The basic mechanism of the tower is what is known as Atwood's apparatus. In the tower, the initial fall of a drop capsule is decelerated by a counterweight connected with a steel wire to the holder of the capsule over a pair of pulleys. After this transitional phase of low gravity, the capsule was released by a mechanical trigger system to start a free fall as reported previously. The changes of the g-value during the fall were recorded using two sensors of different sensitivities (Crossbow, CXL25M1Z, 25 g full scale and CXL02F1Z, 2 g) and a PC card recorder (Teac, DR-C2). The swimming movements of paramecia were observed by a video camera and the video images were transmitted by wireless to a remote videocassette recorder. An experimental chamber containing approximately 200 Paramecium cells was turned from horizontal to upright immediately before the start of the fall. Considerable oscillations in g were observed especially just after the onset of the transient low gravity, which may be caused by vibration of the counterweight and the steel wire connected to the capsule holder. Some changes in parameters of the helical tracks, such as an increase in wavelength of some tracks, were observed after the start of the low gravity phase. Further investigation is necessary to identify the effects of low gravity at various levels. Many paramecia showed ciliary-reversal responses during the fall, some of which might have been induced by the vibration of the capsule. Reducing the mechanical oscillation of the system and using mutants of Paramecium lacking ciliary reversal responses may offer some advantages in further analyses., 資料番号: AA0045438010},
 pages = {29--32},
 publisher = {宇宙科学研究所, The Institute of Space and Astronautical Science (ISAS)},
 title = {2段式落下装置による落下実験},
 year = {2003}
}