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PubMed2004

Culture and tension during an international space station simulation: results from SFINCSS '99.

BACKGROUND: This paper addresses the impact of cultural heterogeneity on interpersonal tension during multinational space missions. METHODS: Data were collected during SFINCSS '99, which simulated the living conditions on ISS. Three crews (n = 12) were confined in connected hyperbaric chambers. Group 1 was confined for 240 d, while Groups 2 and 3 were confined for 110 d. Group 1 was composed of four Russian subjects; Group 2 included three Russian subjects and one non-Russian subject; and Group 3 included Japanese, Russian, Austrian and Canadian subjects. Group 3 included the only female participant. Peer ratings, questionnaires and interviews assessed tension within and between crews, critical incidents and cultural factors impacting on crew interaction. RESULTS: Compared with Group 1, Group 3 evaluated their own group and the Mission Control more negatively. A conflict between Group 1 and 3 was reflected in mutual negative ratings after 1 mo. This situation resulted in an unplanned closure of the hatch between the chambers and in one subject leaving the study prematurely. Group 3 expressed dissatisfaction with mission support and interventions from outside personnel to resolve the interpersonal problems. The entrance of an international visiting crew was reported to alleviate tension between Groups 1 and 3. Language problems and different attitudes toward gender relations were factors identified as having a major impact on the inter-group relationship. CONCLUSIONS: The results may demonstrate some of the difficulties faced by crewmembers belonging to cultural minorities when operational control is in the hands of one national organization, as well as the need for countermeasures designed to address these problems.

Adult↗
PubMed2005

The solar UV environment and bacterial spore UV resistance: considerations for Earth-to-Mars transport by natural processes and human spaceflight.

The environment in space and on planets such as Mars can be lethal to microorganisms because of the high vacuum and high solar radiation flux, in particular UV radiation, in such environments. Spores of various Bacillus species are among the organisms most resistant to the lethal effects of high vacuum and UV radiation, and as a consequence are of major concern for planetary contamination via unmanned spacecraft or even natural processes. This review focuses on the spores of various Bacillus species: (i) their mechanisms of UV resistance; (ii) their survival in unmanned spacecraft, space flight and simulated space flight and Martian conditions; (iii) the UV flux in space and on Mars; (iv) factors affecting spore survival in such high UV flux environments.

Bacillus↗
PubMed1997

Changes in gravity influence rat postnatal motor system development: from simulation to space flight.

Our research examines the role of the environment in postnatal nervous system development. Recently we have been studying the effects of changes in gravity on the motor system of rats from postnatal day (P) 2 to 31 using kinematic analysis of swimming, walking, and righting reflexes. Using the tail suspension model of weightlessness we identified sensitive and critical periods of motor system development corresponding to the time during which a motor skill is first achieved. Motor performance in suspended animals was marked by slow swimming, walking, and air-righting, all of which were characterized by hindlimb extension. (Walton et al, Neurosci. 52,763,1992). The critical periods identified in these studies contributed to determining the age of animals for a small payload, NIH.R3. This 9-day mission (STS-72) included 2 litters at P5, P7, or P15 at launch. The P7-16 and P15-24 groups were studied post-flight. On the landing day (R+0) surface righting, swimming and walking were slower in flight compared to control animals. Differences were more marked in the younger animals and the hindlimbs were more affected than the forelimbs with marked, prolonged extension of, at least, the ankle joint angle. Readaptation to 1G was slower in the P7-16 group with righting reflexes adapting first, walking last. We have shown that gravity is an important factor in postnatal nervous system development and that its affect depends on the age of the animal, duration of the perturbation, and the motor function studied.

Animals↗
PubMedDate not supplied

[Structural and functional disorders of erythrocyte membranes in simulated extravehicle space work].

The experimental data on a structural-and-functional status of erythrocyte membranes in ground-based simulation of human extravehicular activity (EVA) are discussed. The changes in the structure and function of erythrocyte membrane were determined from the fixation of lipophilic ions, specific activity of ion-transporting adenosine triphosphatases and content of the products of peroxide oxidation of lipids (POL) in plasma. On exposure to hypobaric hyperoxia during real EVA the membrane status changes are associated with the activation of a cascade of POL processes.

Adenosine Triphosphatases↗
PubMed2005

Automorphosis of etiolated pea seedlings in space is simulated by a three-dimensional clinostat and the application of inhibitors of auxin polar transport.

Etiolated pea (Pisum sativum L. cv. Alaska) seedlings grown under microgravity conditions in space show automorphosis: bending of epicotyls, inhibition of hook formation and changes in root growth direction. In order to determine the mechanisms of microgravity conditions that induce automorphosis, we used a three-dimensional clinostat and obtained the successful induction of automorphosis-like growth of etiolated pea seedlings. Kinetic studies revealed that epicotyls bent at their basal region towards the clockwise direction far from the cotyledons from the vertical line (0 degrees) at approximately 40 degrees in seedlings grown both at 1 g and in the clinostat within 48 h after watering. Thereafter, epicotyls retained this orientation during growth in the clinostat, whereas those at 1 g changed their growth direction against the gravity vector and exhibited a negative gravitropic response. On the other hand, the plumular hook that had already formed in the embryo axis tended to open continuously by growth at the inner basal portion of the elbow; thus, the plumular hook angle initially increased; this was followed by equal growth on the convex and concave sides at 1 g, resulting in normal hook formation; in contrast, hook formation was inhibited on the clinostat. The automorphosis-like growth and development of etiolated pea seedlings was induced by auxin polar transport inhibitors (9-hydroxyfluorene-9-carboxylic acid, N-(1-naphthyl)phthalamic acid and 2,3,5-triiodobenzoic acid), but not by anti-auxin (p-chlorophenoxyisobutyric acid) at 1 g. An ethylene biosynthesis inhibitor, 1-aminooxyacetic acid, inhibited hook formation at 1 g, and ethylene production of etiolated seedlings was suppressed on the clinostat. Clinorotation on the clinostat strongly reduced the activity of auxin polar transport of epicotyls in etiolated pea seedlings, similar to that observed in space experiments (Ueda J, Miyamoto K, Yuda T, Hoshino T, Fujii S, Mukai C, Kamigaichi S, Aizawa S, Yoshizaki I, Shimazu T, Fukui K (1999) Growth and development, and auxin polar transport in higher plants under microgravity conditions in space: BRIC-AUX on STS-95 space experiment. J Plant Res 112: 487492). These results suggest that clinorotation on a three-dimensional clinostat is a valuable tool for simulating microgravity conditions, and that automorphosis of etiolated pea seedlings is induced by the inhibition of auxin polar transport and ethylene biosynthesis.

Aminooxyacetic Acid↗
PubMed2005

State-resolved unimolecular dissociation of cis-cis HOONO: Product state distributions and action spectrum in the 2nuOH band region.

Nascent OH fragment product state distributions arising from unimolecular dissociation of room temperature HOONO, initiated by excitation in the region of the 2nu(OH) band, are probed using laser-induced fluorescence at sub-Doppler resolution. Phase-space simulations of the measured OH rotational distributions are consistent with the dissociation dynamics being statistical and confirm that all major features in the room temperature action spectrum belong to the cis-cis conformer. The phase-space simulations also allow us to estimate the HO-ONO bond dissociation energy of cis-cis HOONO to be D(0)=19.9+/-0.5 kcal/mol, which when combined with the known heat-of-formation data for the OH and NO(2) fragments gives DeltaH(f) (0)(cis-cis HOONO)=-2.5 kcal/mol. In addition to fragment energy release, spectral features in the cis-cis HOONO action spectrum are examined with respect to their shifts upon (15)N isotope substitution and through ab initio spectral simulation using a two-dimensional dipole surface that takes into account the influence of HOON torsional motion on the OH stretching overtone. The two-dimensional spectral simulations, using CCSD(T)/cc-pVTZ dipole surface, qualitatively reproduces features appearing in the action spectrum and suggest that the strong broad feature occurring approximately 570 cm(-1) to the blue of the cis-cis HOONO 2nu(OH) peak, likely involve excitation of HOON-torsion/OH-stretch combination bands originating from thermally populated excited torsional states. A closer examination of the predictions of the two-dimensional model with experiments also reveals its limitations and suggests that a more elaborate treatment, one which includes several additional modes, will likely be required in order to fully explain the room temperature action spectrum. Ab initio calculations of the HOON torsional potential at the CCSD(T)/cc-pVTZ level of theory are also presented and confirm that cis-perp configuration does not correspond to a bound localized minimum on the HOONO potential energy surface.

Journal Article↗