アナトリー グリゴリエフ 旧ソ連保健省医学生物学問題研究所, 所長
カール クライン ドイツ航空宇宙研究所, 航空宇宙医学研究所, 所長
ジェームス ウォルフ テキサス大学, 生命科学部, 教授
フランク サルツマン NASA本部, 宇宙医学生物学部, 主任
IGARASHI Makoto University Research Center, Nihon University, 総合科学研究所, 教授 (30231731)
ITO Masao Nihon University School of Medicine, 医学部, 講師 (40059887)
MIYAMOTO Akira Nihon University School of Medicine, 医学部, 助教授 (40150271)
KUROKAWA Kiyoshi University of Tokyo, School of Medicine, 医学部, 教授 (30167390)
GRIGORIEV Anatoly I. Institute for Biomedical Problems Ministry of Health of Russia
KLEIN Karl E. Institute for Aerospace Medicine German Aerospace Research Establishment
WOLFE James W. Life Science Division, University of Texas
SULZMAN Frank M. Life Science Division, NASA Headquarters
グリゴリエフ アナトリー 旧ソ連保健省医学生物学研究所, 所長
クライン カール ドイツ航空宇宙研究所, 航空宇宙医学研究所, 所長
ウォルフ ジェームス テキサス大学, 生命科学部, 教授
サルツマン フランク NASA本部, 宇宙医学生物学部, 主任
ウォルフ ジェームズ テキサス大学, 生命科学部, 教授
1. Results of G-load experiments using a short-arm human centrifuge
Based on the artificial G-load experiments by a short-arm human centrifuge before the present research year, we found that the subjects suffered from motion sickness-like symptoms (which is usually seen as a vestibular dysfunction caused by Coriolis stimulation), when a centrifugal force is given in +z (head to heel) direction. Accordingly, in order to avoid the occurrence of vestibular symptoms, we eliminated various mechanical problems such as microvibration. Also, toreduce subject's psychological tension, we have given a very detailed explanation and also used a short-duration experience of centrifugal G-load. First, we acquired data from 5 healthy male subjects, 20-30 years old, by applying 1.2G for 40 minutes, 1.4G for 40 minutes on the following day and then 1.8G for 40 minutes on the next day.
Before and after G-load, we measured various human performances and also obtained a stabilogram which is a measurement of
man's ability of standing postural maintenance. During the load, we recorded EKG, heart rate, respiratory curve, eye movement, pupillary condition, oxygen saturation, and blood pressure (every 1 minute). We continually observed subject's condition through the video camera system. The subject and experimentor could tele-communicate call the time.
As a next step, we tried to expose subjects to 2.0G for 40 minutes. Except for subject who could complete this load at his second trial, the load had to be stopped, for all subjects who complained an extreme unpleasantness or hardness and manifested objective symptoms such as low blood pressure. Thereafter, we decided to extend the exposure period for 60 minutes instead, and started from 1.4G. If the subject could complete a 1.4G load, the level went up to 1.7G. If he could not complete 1.7G, he had to go back to 1.4G again. Based on our data to present, we set the maximal level as 2.0G for 60 minutes and we did not use any higher or longer exposure. To data, 9 subjects completed 1.4G load for 60 minutes, but 4 could not ; 6 completed 1.7G for 60 minutes but 5 could not ; and 3 completed 2.0G for 60 minutes but 3 could not.
Subjects who failed to complete the G load showed various autonomic nervous system symptoms such as cold sweat, tachycardia, head heaviness etc., and they complained the condition as intolerable. Symptoms like low blood pressure, brain anemia etc. due to circulatory failure by an extreme G load, and heart rate reduction by vagotony were not found in this subject group. performance by subjects who could complete the scheduled G level load returned to the preexposure performance level within 2 hours.
2. Reports at the international meetings and international information exchange
Members of our research group and research collaborators have made multiple presentations in relation to the centrifugal G-load, at many international meetings and congresses ; in Nagoya, March, 1992 ; in Miami Beach, May, 1992 ; in Washington,D.C., August, 1992 ; in Hawaii, September, 1992 ; in Tokyo, October, 1992. Our new and unexpected findings on brain circulation during G-load have delivered a great impact to the related research community. Furthermore, life science and medical leaders in NASA organization have clearly recognized the importance of artificial G-load experiments, and intend to support an active exchange of information among the international research groups.
The Man-in-Space Symposium of the International Association of Astronautics will be held in Tokyo, April, 1993, under the chairmanship of the Principal Investigator. During this meeting, we scheduled to have a special session of "artificial gravity", as a summerization of our research works to data. During this unique and very first study session on "artificial gravity", out of a total of 9 papers, we will have 5 presentations from Japan (4 from our group), 3 from U.S.A. and 1 from Russia.
After the initiation of Clinton administration, the future of the space program does not look very bright, and some grim views exist among the global space community. Sometime ago, we have structured an international study forum of artificial gravity research. Unfortunately, the system is not functioning properly at this moment, basically due to somewhat inactive movement of NASA people. This exemplifies the real difficulty of international collaboration. Nonetheless, we are anxious to continue our artificial G load studies. Less