著者
Takeshi Naganuma Hirohiko Uematsu
出版者
日本宇宙生物科学会
雑誌
Biological Sciences in Space (ISSN:09149201)
巻号頁・発行日
vol.12, no.2, pp.126-130, 1998 (Released:2006-02-01)
参考文献数
25
被引用文献数
5 10

Liquid water, underwater volcanoes and possibly life forms have been suggested to be present beneath the estimated 10 km-thick ice shell of Europa, the Jovian satellite J2. Europa's possible ocean is estimated to be 100-200 km deep. Despite the great depth of the Europa's ocean, hydrostatic pressure at the seafloor would be 130-260 MPa, corresponding to 13-26 km depth of a theoretical Earth's ocean. The hydrostatic pressure is not beyond the edge of existing deep-sea technology. Here we propose exploration of Europa's deep-sea by the use of current technologies, taking a symbolic example of a deep submergence vehicle Shinkai 6500 which dives to a depth of 6.5 km deep (50 km depth of Europa's ocean). Shinkai 6500 is embarkable in the payload bay of the Space Shuttles in terms of size and weight for the transportation to a Low Earth Orbit (LEO). Secondary boost is needed for interplanetary flight from the LEO.On-orbit assembly of the secondary booster is a technological challenge. The International Space Station (ISS) and ISS-related technologies will facilitate the secondary boost. Also, ice shell drilling is a challenge and is needed before the dive into Europa's ocean. These challenges should be overcome during a certain leading time for matured experience in the ISS operation.
著者
笹山 雄一
出版者
日本宇宙生物科学会
雑誌
Biological Sciences in Space (ISSN:09149201)
巻号頁・発行日
vol.15, no.1, pp.3-14, 2001 (Released:2006-02-01)
参考文献数
43
被引用文献数
2 2

On April 12, 1961, Major Yurii A. Gagarin of the former-U.S.S.R. Air Force circled the Earth in a spacecraft named “Vostok”, a word which means “east”. He spent 1 hour and 48 minutes in space. Since then, the U.S.S.R. and the U.S.A. have sent many astronauts into space. In one case, the stay in space exceeded a year in length, reaching 438 days. Through these experiences, it became clear that micro-gravity caused various problems in human physiology. One of the most serious problems was the loss of Ca from bones, as a result of the negative expenditure of Ca. Under 1G on the ground, bone absorption and bone formation proceed in accordance. Under micro-gravity, however, this balance is broken. Although this phenomenon has been widely analyzed from the viewpoint of molecular biology as well, studies to clarify the mechanism that causes the disorder of Ca metabolism in bones have just started. At present, no perfect treatment to prevent the loss of Ca from bones is available.
著者
幸島 司郎
出版者
日本宇宙生物科学会
雑誌
Biological Sciences in Space (ISSN:09149201)
巻号頁・発行日
vol.14, no.4, pp.353-362, 2000 (Released:2006-02-01)
参考文献数
41
被引用文献数
3 4

Psychrophilic and psycrotrophic organisms are important in global ecology as a large proportion of our planet is cold. Two-third of sea-water covering more than 70% of Earth is cold deep sea water with temperature around 2°C, and more than 90% of freshwater is in polar ice-sheets and mountain glaciers. Though biological activity in snow and ice had been believed to be extremely limited, various specialized biotic communities were recently discovered at glaciers of various part of the world. The glacier is relatively simple and closed ecosystem with special biotic community containing various psychrophilic and psycrotrophic organisms. Since psychrophilic organisms was discovered in the deep ice-core recovered from the antarctic ice-sheet and a lake beneath it, snow and ice environments in Mars and Europa are attracting a great deal of scientific attention as possible extraterrestrial habitats of life. This paper briefly reviews the results of the studies on ecology of psychrophilic organisms living in snow and ice environments and their physiological and biochemical adaptation to low temperature.
著者
松波 謙一
出版者
日本宇宙生物科学会
雑誌
Biological Sciences in Space (ISSN:09149201)
巻号頁・発行日
vol.11, no.2, pp.87-110, 1997 (Released:2006-02-01)
参考文献数
141
被引用文献数
2

Investigation of the vestibulo-ocular system of the squirrel monkey was reviewed in consideration of space motion sickness (SMS), or which is recently more often termed as space adaptation syndrome (SAS). Since the first launching of the space satellite,Sputonik in October 1957, many experiments were carried out in biological and medical fields. A various kind of creatures were used as experimental models from protozoa to human beings. Rats and monkeys are most favorite animals, particularly the non-human primate seems to be the one, because of its phylogenetic relatives akin to the human beings. Chimpanzees, rhesus monkeys, pig tailed-monkeys, red-faced monkeys and squirrel monkeys have been used mostly in American space experiments. Russian used rhesus monkeys. Among these, however, the squirrel monkey has an advantage of the small size of the body, ranging from 600-1000g in adult. This small size as a primate is very advantageous in experiments conducted in a narrow room of the space satellite or shuttle because of its space-saving. The squirrel monkey has another advantage to rear easily as is demonstrated to keep it as a pet. Accordingly, this petit animal provides us a good animal model in biological and medical experiments in space craft. The size of the brain of the squirrel monkey is extraordinary large relative to the body size, which is even superior to that of the human beings. This is partly owed to enlargement of the occipito-temporal cortices, which are forced to well develop for processing a huge amount of audio-visual information indispensable to the arboreal habitant to survive in tropical forest. The vestibular system of the squirrel monkey seems to be the most superior as well, when judged from it relative size of the vestibular nuclear complex. Balancing on swinging twigs or jumping from tree to tree developed the capability of this equilibrium system. Fernndez, Goldberg and his collaborators used the squirrel monkey to elucidate functions of the peripheral vestibular system. A transfer function was proposed to explain the behaviors of regular and irregular unit activity of vestibular nerve fibers. The physiologic characteristics of the second order vestibular neuron was investigated in combination of electrophysiological and micro-morphological way, with using WGA-HRP methods, in relation to somato-motor and eye movements. Interconnections between vestibular neurons and cerebellum, interstitial nucleus of Cajal, oculomotor nuclear complex, superior colliculus and cervical spinal cord were elucidated. In physiological field of the vestibular system, the vestibulo-ocular reflex is well studied and results obtained from the squirrel monkey experiments were reviewed. The squirrel monkey, particularly the Bolivian, is a unique animal in that it is vulnerable to motion sickness induced by visual-motion stimulation with phase mismatch of the two stimuli. Experimental results of labyrinthectomy or bilateral ablation of the maculae staticae led to the conclusion that both semicircular and otolith organs are involved in the genesis of space motion sickness. On the other hand,destruction of the area postrema, acknowledged as the vomiting center to chemical stimulants, produced controversial results. However, it must be pointed out that the a human subject underwent to resection of the area postrema, became insensitive to administration of apomorphine, a well known chemical stimulant of vomiting. Finally the experiments in space revealed the presence of at least two origins of caloric nystagmus, that is, attributable to convection and non-convection current of the endolymphatic fluid.
著者
柴籐 洋二
出版者
日本宇宙生物科学会
雑誌
Biological Sciences in Space (ISSN:09149201)
巻号頁・発行日
vol.9, no.2, pp.95-105, 1995 (Released:2006-02-01)

The development program of the H-II rocket has been initiated in 1985. The H-II rocket is a new expendable launch vehicle to meet a demand of space activities in the 1990's. With the successful development if the N rocket family,, Japan has established the technology for launching satellite into Geostationary Earth Orbit (GEO). The National Space Development Agency of Japan(NASDA) has made a major effort to obtain a heavier launch vehicle, capable of meeting the increasing needs of GEO mission. Following the II 1 rocket capable of carrying a 550 kilogram satellite into GEO and ready for a first launch in August 1986, a new launch vehicle called the H-II rocket is being planned to carry a 2 ton satellite into GEO and to be most cost effective per payload ton into GEO. This launch vehicle is of 100 percent domestic design and Japan will be able to have an independent and competitive capability in the field of space transportation systems. First launch of the H-II rocket was performed successfully in February 1994. After that, second and third H-II rocket were launched in august 1994 and march 1995.
著者
Natsuhiro Takahashi Masamichi Takami Masahiro Chatani
出版者
Japanese Society for Biological Sciences in Space
雑誌
Biological Sciences in Space (ISSN:09149201)
巻号頁・発行日
vol.35, pp.24-31, 2021 (Released:2021-09-01)
参考文献数
18

Bones are important organs for body resistance against force produced by gravity, though the influence of gravity on bone development is unclear. To examine the effects of gravity on osteogenesis, medaka larvae were reared in water or gel under various conditions. For determining the effects on bone development in a state of motion, larvae were reared in water under normal gravity (1g) or hypergravity (5g) conditions. Also, to examine the direct effect of gravity on bone mineralization, larvae were embedded in low melting agarose gel containing alizarin complexone (ALC) and reared for three days under a normal gravity (1g), simulated-microgravity (s-μg) with use of a clinostat device, or 5g condition. Medaka reared in water under the 5g condition showed forward protruding jaws and spreading of the mineralized area of jaw teeth as compared to those reared under the 1g control condition. In addition, the direction of growth of the notochord in the fin region was changed upward in those reared under the 5g condition, accompanied by a part of acetylated tubulin-positive nerves also localized upward, while positive signals for DsRed, expressed by an osterix promoter, in osteoblasts were increased in the fin region. On the other hand, in medaka reared in gel, ALC signals in the fin ray of those in the s-μg condition were increased as compared to those in the 5g condition. Changes noted in medaka larvae over three days indicated osteogenesis adaptation to the specific gravity environment. The present results obtained with an experimental system are considered useful for examinations in the future regarding changes of osteogenesis, which will be needed to clarify the mechanism of the effects of gravity on bone development.
著者
長谷川 眞理子
出版者
日本宇宙生物科学会
雑誌
Biological Sciences in Space (ISSN:09149201)
巻号頁・発行日
vol.19, no.3, pp.186-199, 2005 (Released:2006-03-30)

Human nature is a product of human brain activity, and human brain is an organ which functions to assess environmental information and to make decision about what to do next. Many aspects of human nature must be the results of evolution through natural selection in which favorable genes were selected under the environmental stress. Now, we live in civilized societies based on highly developed technology, using computers, contemplating about the relativity theory, mastering the calculus etc. However, this was not an environment where our basic human nature evolved. That environment was the one which surrounded our ancestors. Humans lived as hunter-gatherers in most of the time during evolution, and the human brain evolved to solve those problems confronted at those times. The resulting decision-making algorithms were so flexible that we can now deal with novel problems of our time using the same old decision-making algorithm. The evolution of behavior is a very complex process and no one gene is controlling any particular behavior. Genes are indeed involved in producing adaptive behavior but a behavior is produced through many other pathways as well, such as learning. We have evolved a huge brain which is capable of producing culture. Culture is a human creation but at the same time, culture has become our environment to which we have to adapt. Thus gene-culture coevolution has been a very important process in human evolution. After we have acquired language, perhaps we have acquired an almost unlimited cognitive power. Many of our cultural invention is the results of our cognitive activity and these things have become parts of our environment. However, cognition is only a small part of the workings of our brain. Human nature is also under control of emotion. Emotional processes are mostly subconscious and have changed little through evolutionary time. In the future, misfits between our cognitive products and emotional process may create many difficult problems which we have never experiences so far.
著者
Masamichi Yamashita Akemi Izumi-Kurotani Yoshihiro Mogami Makoto Okuno Tomio Naitoh Richard J. Wassersug
出版者
Japanese Society for Biological Sciences in Space
雑誌
Biological Sciences in Space (ISSN:09149201)
巻号頁・発行日
vol.11, no.4, pp.313-320, 1997 (Released:2006-02-01)
参考文献数
32
被引用文献数
11 17

The “Frog in Space” (FRIS) experiment marked a major step for Japanese space life science, on the occasion of the first space flight of a Japanese cosmonaut. At the core of FRIS were six Japanese tree frogs, Hyla japonica, flown on Space Station Mir for 8 days in 1990. The behavior of these frogs was observed and recorded under microgravity. The frogs took up a “parachuting” posture when drifting in a free volume on Mir. When perched on surfaces, they typically sat with their heads bent backward. Such a peculiar posture, after long exposure to microgravity, is discussed in light of motion sickness in amphibians. Histological examinations and other studies were made on the specimens upon recovery. Some organs, such as the liver and the vertebra, showed changes as a result of space flight; others were unaffected. Studies that followed FRIS have been conducted to prepare for a second FRIS on the International Space Station. Interspecific diversity in the behavioral reactions of anurans to changes in acceleration is the major focus of these investigations. The ultimate goal of this research is to better understand how organisms have adapted to gravity through their evolution on earth.
著者
山下 雅道 山下 明子 山田 晃弘
出版者
日本宇宙生物科学会
雑誌
Biological Sciences in Space (ISSN:09149201)
巻号頁・発行日
vol.11, no.2, pp.112-118, 1997 (Released:2006-02-01)
参考文献数
19
被引用文献数
16 17

Three dimensional clinostat has been developed for simulation of microgravity on ground. It has applied in many disciplines in gravitational biology. Outline of operational principle is described together with its mechanical design. Rotation around two independent axes makes direction of gravity vector to scan whole steric angle. Magnitude and direction of rotational angular velocity is selected randomly at a certain interval of time to avoid singularity in sweep trajectory of gravity vector. Methods for validation of the operation are presented to test randomness of motion and cancellation of gravity by clino-rotation. Concerns discussed are vibration originated in motor and pseudo-weak magnetic field generated on clinostat. Fluid flow induced by clino-rotation is pointed as another problem to be taken into account.
著者
小池 惇平 大島 泰郎
出版者
日本宇宙生物科学会
雑誌
Biological Sciences in Space (ISSN:09149201)
巻号頁・発行日
vol.4, no.1, pp.3-8, 1990 (Released:2006-02-01)
被引用文献数
5 4

In connection with planetary quarantine, we are studying how terrestrial microorganisms can survive in the cosmic environments. If comon terrestrial microorganisms can not survive in the space even for a short period, we can reduce the cost for sterilizing space probes. The interstellar environments has been simulated by using ultra low temperature high vacuum ( 77 K, 10-6 torr ) improved crynostat and ptoton irradiation from Van de Graaff genarator in the Tokyo Institute of Technology. Various species of terrestrial microorganisms, virus, bacteria, actinomycetes, yeast and fungi were tested quantitatively inactivity under simulated space conditions. After exposing a barrage of the protons corresponding to 250 years irradiation in Space, it was shown that spores of Bacillus subtilis and Aspergillus niger and tabaco mosaic virus can survive about 45%. 25% and 82%, respectively. The results are consistent to report by Weber and Greenberg that spore of B. subtiIis survived 10% under simulated conditions after UV irradiation corresponding to 500 years exposure in space. It might be presumed that the survived terrestrial microorganisms come back to mother earth in future as pathogenic mutants by irradiation of cosmic rays.
著者
Kenichi Ijiri
出版者
Japanese Society for Biological Sciences in Space
雑誌
Biological Sciences in Space (ISSN:09149201)
巻号頁・発行日
vol.9, no.1, pp.3-16, 1995 (Released:2006-02-01)
被引用文献数
33 49

The code name ‘MEDAKA’ was given to the fish experiment in the IML-2 (the second International Microgravity Laboratory), a Space-shuttle mission (STS-65) carried out in July 1994. Medaka is the Japanese name for a small fresh-water fish, Oryzias latipes. This experiment titled ‘Mating behavior of the fish Medaka and development of their eggs in space’ aimed to present data for designing the future fish-culture in space. The Medaka experiment accomplished its objectives to the point of 100 %. The fish mated, laid eggs in space, and these eggs developed normally to hatching (coming out as a baby fish) under microgravity. Its success totally depended on selection of the four fish sent to space. This paper describes the aims of the IML-2 Medaka fish experiment and how it was prepared, together with a brief report on what were achieved in space.
著者
杉山 貞夫
出版者
日本宇宙生物科学会
雑誌
Biological Sciences in Space (ISSN:09149201)
巻号頁・発行日
vol.3, no.1, pp.31-37, 1989 (Released:2006-02-01)

From the beginning of the space project to the end of it where the mission is completed, human factors consideration has to be paid to every sector of the developmental and achievement process of the space architecture as well as of the total system where human beings are involved. Human factors, originating from the human life on the earth, have aimed to accomplish a high level of reliability, efficiency, safety and other criterion variables that affect the quality of product, of mission, and of service, which are utilized on the earth. Now we are planning to design a complex system of space facility to be used in the space, where every human function is supposed to be quite different from that on the earth. In the space, some of the combinations of variables which we aim to accomplish might be entirely new for us mainly due to different physical characteristics. Now we need information and knowledges produced not only by any scientific disciplines which directly correspond with the object area. but also by combinations of disciplines, if we want to accomplish the goal. Human sciences, which have supported human factors, have numerous sectors of sciences. They are distributed from molecular biology to sociology in a wide range of spectrum. Therefore, a wide range of all sorts of sectors of human sciences has to be involved in the research on humans in space. Those sciences must cooperatively provide information and knowledges for the human factors design of space architecture and systems to be used in space.
著者
Masahiro Chatani Aiko Mitsuhashi Yusuke Dodo Nobuhiro Sakai Masamichi Takami
出版者
Japanese Society for Biological Sciences in Space
雑誌
Biological Sciences in Space (ISSN:09149201)
巻号頁・発行日
vol.33, pp.12-17, 2019 (Released:2019-09-10)
参考文献数
18
被引用文献数
3

Teleost fish live under a constant force derived from gravity, with hard tissues playing important roles to help maintain body balance. However, the mechanism of hard tissue formation induced by gravity remains unclear. To examine the effects of gravity in aquatic animals, we performed experiments with medaka fish reared in a hypergravity environment, in which the force of gravity exceeded that present on the surface of the Earth, and analyzed hard tissue formation. Medaka fish were reared for 6 months under a normal gravitational force (1G) or that 5.29 times greater than normal (5.29G) using a centrifuge designated for small fish rearing. Micro-CT analysis results showed that hypergravity induced a vertebral curvature towards the dorsal side and asymmetric formation of otoliths in which the cross-sectional area was increased. Our findings indicate that the process of adaptation to a hypergravity environment results in spinal and otolith deformation in medaka fish.
著者
Yinjie Yang Shin-ichi Yokobori Akihiko Yamagishi
出版者
Japanese Society for Biological Sciences in Space
雑誌
Biological Sciences in Space (ISSN:09149201)
巻号頁・発行日
vol.23, no.3, pp.151-163, 2009 (Released:2010-08-06)
参考文献数
133
被引用文献数
12 17

Microbiology at the high altitude atmosphere is important for assessing the chances and limits of microbial transfer from the earth to extraterrestrial bodies. Among the microorganisms isolated from the high-atmospheric samples, spore formers and vegetative Deinococci were highly resistant against harsh environment at high altitude. From limited knowledge available to date, it is suggested that terrestrial microorganisms may have had chances to be ejected and transferred to outer space. Survival of these organisms during their space travel and proliferation on other planets might be also feasible. Directed Panspermia from Earth to extraterrestrial bodies is discussed on the basis of findings reported in literatures.
著者
井尻 憲一
出版者
日本宇宙生物科学会
雑誌
Biological Sciences in Space (ISSN:09149201)
巻号頁・発行日
vol.16, no.2, pp.47-55, 2002 (Released:2006-01-31)
参考文献数
11

In this review paper, organismal and also cellular mechanisms for perception of gravity are explained. A statolith and a number of hair cells which surround the statolith is a basic structure of statocysts for detecting the direction of gravity or tilting of the body in various animals. The vestibular system of vertebrate was explained, especially on the process from the body-tilting to impulse frequencies which travel to brain. For the cellular responses to gravity, contribution of various organella(??) and cytoskeleton are introduced. Such cellular responses may change when the gravity values become less or null. Gravity perception mechanisms of plants are also explained.
著者
菅 洋
出版者
日本宇宙生物科学会
雑誌
Biological Sciences in Space (ISSN:09149201)
巻号頁・発行日
vol.1, no.1, pp.9-18, 1987 (Released:2006-02-01)
被引用文献数
1 1

Physical stimulus is one of the important factors in space environment other than microgravity. In this article, several aspects on the physical stimulus in relation to plant growth were reviewed. Reduction in stem elongation and an increase in radial thickness are the general growth features that caused by physical stimulus inevitable in the course of space ship launce and its way in space navigation. Internal changes observed in cellular, biochemical and metabolic levels are also discussed, and several problems that must be considered in plant cultivation in space environment were pointed ourt with the viewpoint of physical stimulation.
著者
Monika Fejtek Michel Delorme Richard Wassersug
出版者
Japanese Society for Biological Sciences in Space
雑誌
Biological Sciences in Space (ISSN:09149201)
巻号頁・発行日
vol.9, no.2, pp.77-81, 1995 (Released:2006-02-01)
参考文献数
18
被引用文献数
1 1

As part of an ongoing survey of the behavioral responses of vertebrates to abrupt changes in gravity, we report here on the reactions of bats (Carollia perspicillata) exposed to altered gravity during parabolic aircraft flight. In microgravity, mammals typically behave as if they were upside-down and exhibit repetitive righting reflexes, which often lead to long axis rolling. Since bats, however, normally rest upside-down, we hypothesized that they would not roll in microgravity. Only one of three specimens attempted to fly during microgravity. None rolled or performed any righting maneuvers. During periods of microgravity the bats partially extended their forearms but kept their wings folded and parallel to the body. Between parabolas and occasionally during microgravity the bats groomed themselves. Both the extended limbs and autogrooming may be stress responses to the novel stimulus of altered gravity. This is the first behavioral record of Chiroptera in microgravity.
著者
保尊 隆享 若林 和幸 曽我 康一
出版者
日本宇宙生物科学会
雑誌
Biological Sciences in Space (ISSN:09149201)
巻号頁・発行日
vol.17, no.2, pp.135-143, 2003 (Released:2006-01-31)
参考文献数
31

The involvement of anti-gravitational polysaccharides in gravity resistance, one of two major gravity responses in plants, was discussed. In dicotyledons, xyloglucans are the only cell wall polysaccharides, whose level, molecular size, and metabolic turnover were modified under both hypergravity and microgravity conditions, suggesting that xyloglucans act as anti-gravitational polysaccharides. In monocotyledonous Poaceae, (1→3),(1→4)-b-glucans, instead of xyloglucans, were shown to play a role as anti-gravitational polysaccharides. These polysaccharides are also involved in plant responses to other environmental factors, such as light and temperature, and to some phytohormones, such as auxin and ethylene. Thus, the type of anti-gravitational polysaccharides is different between dicotyledons and Poaceae, but such polysaccharides are universally involved in plant responses to environmental and hormonal signals. In gravity resistance, the gravity signal may be received by the plasma membrane mechanoreceptors, transformed and transduced within each cell, and then may modify the processes of synthesis and secretion of the anti-gravitational polysaccharides and the cell wall enzymes responsible for their degradation, as well as the apoplastic pH, leading to the cell wall reinforcement. A series of events inducing gravity resistance are quite independent of those leading to gravitropism.
著者
森 滋夫
出版者
日本宇宙生物科学会
雑誌
Biological Sciences in Space (ISSN:09149201)
巻号頁・発行日
vol.6, no.3, pp.142-146, 1992 (Released:2006-02-01)

A variety of animal behavior under microgravity has been found in the experiments using parabolic aircraft flights and in space. Forward looping in fish and tadpoles is contrast to backward looping of pigeons, while frogs and hamsters extend their extremities with the head turning backward. Postures of monkeys and man, on the other hand, are different from those of above animals. Loss of vestibular input must be common to all of these animals and there may be some similarities among the species in the sensory conflict against it. Advancing animals experiments in space, it is important to make further progress in comparative neurology particularly regarding the posture control and behavior of animals.