WorldWideScience

Sample records for weightlessness

  1. Counteracting Hypertension with weightlessness?

    DEFF Research Database (Denmark)

    Norsk, Peter

    2008-01-01

    Many of us have been told to lose weight to lower our blood pressure, but going weightless? Studies of astronauts show that gravity does contribute to cardiovascular stress......Many of us have been told to lose weight to lower our blood pressure, but going weightless? Studies of astronauts show that gravity does contribute to cardiovascular stress...

  2. [Mechanism of cardiac atrophy under weightlessness/simulated weightlessness].

    Science.gov (United States)

    Zhong, Guo-Hui; Ling, Shu-Kuan; Li, Ying-Xian

    2016-04-25

    Cardiac remodeling is the heart's response to external or internal stimuli. Weightlessness/simulated weightlessness leads to cardiac atrophy and heart function declining. Understanding the mechanism of cardiac atrophy under weightlessness is important to help astronaut recover from unloading-induced cardiovascular changes after spaceflight. Unloading-induced changes of hemodynamics, metabolic demands and neurohumoral regulation contribute to cardiac atrophy and function declining. During this process, Ca(2+)-related signaling, NF-κB signaling, ERK signaling, ubiquitin-proteasome pathway and autophagy are involved in weightlessness-induced cardiac atrophy. This article reviews the underlying mechanism of cardiac atrophy under weightlessness/simulated weightlessness.

  3. Antinatriuretic kidney response to weightlessness

    Science.gov (United States)

    Gerzer, R.; Drummer, C.; Heer, M.

    We have tested the effects of weightlessness on renal function in one subject who flew the recent week-long Russian-German MIR'92 space mission. Urine flow, renal sodium excretion, and the excretion of urodilatin were measured during the first and last days of the flight. Our results demonstrated, in contrast to expectations, that urine flow and sodium excretion during weightlessness were actually lower than the values obtained during preflight measurements. These results therefore are inconsistent with the commonly held hypothesis that weightlessness induces a diuresis and natriuresis in human subjects. It would seem that further studies are necessary to resolve this issue and to determine whether currently used ground-based models of weightlessness correctly predict physiological adaptations that occur during space flight.

  4. Animal models for simulating weightlessness

    Science.gov (United States)

    Morey-Holton, E.; Wronski, T. J.

    1982-01-01

    NASA has developed a rat model to simulate on earth some aspects of the weightlessness alterations experienced in space, i.e., unloading and fluid shifts. Comparison of data collected from space flight and from the head-down rat suspension model suggests that this model system reproduces many of the physiological alterations induced by space flight. Data from various versions of the rat model are virtually identical for the same parameters; thus, modifications of the model for acute, chronic, or metabolic studies do not alter the results as long as the critical components of the model are maintained, i.e., a cephalad shift of fluids and/or unloading of the rear limbs.

  5. Physiological mechanisms of the effect of weightlessness on the body

    Science.gov (United States)

    Kasyan, I. I.; Kopanev, V. I.

    1975-01-01

    Experimental data show that physiological reactions observed under weightlessness conditions are caused by: (1) The direct effect of weightlessness, as a consequence of decrease (""disappearance'') of the weight of body tissues and organs; and (2) the mediated effect of weightlessness, as a result of changes in the functional state of the central nervous system and the cooperative work of the analyzers. The human body adopts to weightless conditions under the prolonged effects of it. In this case, four periods can be distinguished: The first period, a transitional process lasting from 1 to 24 hours; second period, initial adaptation to conditions of weightlessness and readjustment of all functional systems of the body; the third period, adaptation to the unusual mechanical conditions of the external environment, lasting from 3 to 8 days and more; and the fourth period, the stage of possible imbalance of the functions and the systems of some astronauts, as a result of the prolonged effect of weightlessness.

  6. Impact of weightlessness on muscle function

    Science.gov (United States)

    Tischler, M. E.; Slentz, M.

    1995-01-01

    The most studied skeletal muscles which depend on gravity, "antigravity" muscles, are located in the posterior portion of the legs. Antigravity muscles are characterized generally by a different fiber type composition than those which are considered nonpostural. The gravity-dependent function of the antigravity muscles makes them particularly sensitive to weightlessness (unweighting) resulting in a substantial loss of muscle protein, with a relatively greater loss of myofibrillar (structural) proteins. Accordingly alpha-actin mRNA decreases in muscle of rats exposed to microgravity. In the legs, the soleus seems particularly responsive to the lack of weight-bearing associated with space flight. The loss of muscle protein leads to a decreased cross-sectional area of muscle fibers, particularly of the slow-twitch, oxidative (SO) ones compared to fast-twitch glycolytic (FG) or oxidative-glycolytic (FOG) fibers. In some muscles, a shift in fiber composition from SO to FOG has been reported in the adaptation to spaceflight. Changes in muscle composition with spaceflight have been associated with decreased maximal isometric tension (Po) and increased maximal shortening velocity. In terms of fuel metabolism, results varied depending on the pathway considered. Glucose uptake, in the presence of insulin, and activities of glycolytic enzymes are increased by space flight. In contrast, oxidation of fatty acids may be diminished. Oxidation of pyruvate, activity of the citric acid cycle, and ketone metabolism in muscle seem to be unaffected by microgravity.

  7. Impact of weightlessness on muscle function

    Science.gov (United States)

    Tischler, M. E.; Slentz, M.

    1995-01-01

    The most studied skeletal muscles which depend on gravity, "antigravity" muscles, are located in the posterior portion of the legs. Antigravity muscles are characterized generally by a different fiber type composition than those which are considered nonpostural. The gravity-dependent function of the antigravity muscles makes them particularly sensitive to weightlessness (unweighting) resulting in a substantial loss of muscle protein, with a relatively greater loss of myofibrillar (structural) proteins. Accordingly alpha-actin mRNA decreases in muscle of rats exposed to microgravity. In the legs, the soleus seems particularly responsive to the lack of weight-bearing associated with space flight. The loss of muscle protein leads to a decreased cross-sectional area of muscle fibers, particularly of the slow-twitch, oxidative (SO) ones compared to fast-twitch glycolytic (FG) or oxidative-glycolytic (FOG) fibers. In some muscles, a shift in fiber composition from SO to FOG has been reported in the adaptation to spaceflight. Changes in muscle composition with spaceflight have been associated with decreased maximal isometric tension (Po) and increased maximal shortening velocity. In terms of fuel metabolism, results varied depending on the pathway considered. Glucose uptake, in the presence of insulin, and activities of glycolytic enzymes are increased by space flight. In contrast, oxidation of fatty acids may be diminished. Oxidation of pyruvate, activity of the citric acid cycle, and ketone metabolism in muscle seem to be unaffected by microgravity.

  8. Correlation of macro and micro cardiovascular function during weightlessness and simulated weightlessness

    Science.gov (United States)

    Hutchins, P. M.; Marshburn, T. H.; Smith, T. L.; Osborne, S. W.; Lynch, C. D.; Moultsby, S. J.

    1988-01-01

    The investigation of cardiovascular function necessarily involves a consideration of the exchange of substances at the capillary. If cardiovascular function is compromised or in any way altered during exposure to zero gravity in space, then it stands to reason that microvascular function is also modified. We have shown that an increase in cardiac output similar to that reported during simulated weightlessness is associated with a doubling of the number of post-capillary venules and a reduction in the number of arterioles by 35%. If the weightlessness of space travel produces similar changes in cardiopulmonary volume and cardiac output, a reasonable expectation is that astronauts will undergo venous neovascularization. We have developed an animal model in which to correlate microvascular and systemic cardiovascular function. The microcirculatory preparation consists of a lightweight, thermo-neutral chamber implanted around intact skeletal muscle on the back of a rat. Using this technique, the performed microvasculature of the cutaneous maximus muscle may be observed in the conscious, unanesthetized animal. Microcirculatory variables which may be obtained include venular and arteriolar numbers, lengths and diameters, single vessel flow velocities, vasomotion, capillary hematocrit anastomoses and orders of branching. Systemic hemodynamic monitoring of cardiac output by electromagnetic flowmetry, and arterial and venous pressures allows correlation of macro- and microcirculatory changes at the same time, in the same animal. Observed and calculated hemodynamic variables also include pulse pressure, heart rate, stroke volume, total peripheral resistance, aortic compliance, minute work, peak aortic flow velocity and systolic time interval. In this manner, an integrated assessment of total cardiovascular function may be obtained in the same animal without the complicating influence of anesthetics.

  9. Germination of pine seed in weightlessness (investigation in Kosmos 782)

    Science.gov (United States)

    Platonova, R. N.; Parfenov, G. P.; Olkhovenko, V. P.; Karpova, N. I.; Pichugov, M. Y.

    1978-01-01

    An investigation was made of the orientation of aboveground and underground organs of pine plants grown from seed in weightlessness. Orientation was found to be caused by the position of the seeds relative to the substrate surface. Normal growth was manifest only for the plants grown from seed oriented with embryo toward the substrate. Differences were noted between experiment and control as to the quantitative content of nucleoli in the meristematic cells of the rootlets and the shape of cells in the cotyledonous leaflets. No complete agreement was found between data obtained in weightlessness and when gravity was compensated (clinostat treatment with horizontal rotation).

  10. FPGA implementation of a pyramidal Weightless Neural Networks learning system.

    Science.gov (United States)

    Al-Alawi, Raida

    2003-08-01

    A hardware architecture of a Probabilistic Logic Neuron (PLN) is presented. The suggested model facilitates the on-chip learning of pyramidal Weightless Neural Networks using a modified probabilistic search reward/penalty training algorithm. The penalization strategy of the training algorithm depends on a predefined parameter called the probabilistic search interval. A complete Weightless Neural Network (WNN) learning system is modeled and implemented on Xilinx XC4005E Field Programmable Gate Array (FPGA), allowing its architecture to be configurable. Various experiments have been conducted to examine the feasibility and performance of the WNN learning system. Results show that the system has a fast convergence rate and good generalization ability.

  11. [Influence of weightlessness on water and electrolytes balance in body].

    Science.gov (United States)

    Shen, X Y

    2000-02-01

    The balance of water and electrolytes plays an important role in enabling the human body to adapt to spaceflight. This paper introduced the research methods, and changes in water and electrolytes balance during and after space flight. The mechanism and the hazard of the disorder of water and electrolytes caused by weightlessness were discussed.

  12. Modeling of Cardiovascular Response to Weightlessness

    Science.gov (United States)

    Sharp, M. Keith

    1999-01-01

    It was the hypothesis of this Project that the Simple lack of hydrostatic pressure in microgravity generates several purely physical reactions that underlie and may explain, in part, the cardiovascular response to weightlessness. For instance, hydrostatic pressure within the ventricles of the heart may improve cardiac performance by promoting expansion of ventricular volume during diastole. The lack of hydrostatic pressure in microgravity might, therefore, reduce diastolic filling and cardiac performance. The change in transmural pressure is possible due to the difference in hydrostatic pressure gradients between the blood inside the ventricle and the lung tissue surrounding the ventricle due to their different densities. On the other hand, hydrostatic pressure within the vasculature may reduce cardiac inlet pressures because of the typical location of the heart above the hydrostatic indifference level (the level at which pressure remains constant throughout changes in gravity). Additional physical responses of the body to changing gravitational conditions may influence cardiovascular performance. For instance, fluid shifts from the lower body to the thorax in microgravity may serve to increase central venous pressure (CVP) and boost cardiac output (CO). The concurrent release of gravitational force on the rib cage may tend to increase chest girth and decrease pedcardial pressure, augmenting ventricular filling. The lack of gravity on pulmonary tissue may allow an upward shifting of lung mass, causing a further decrease in pericardial pressure and increased CO. Additional effects include diuresis early in the flight, interstitial fluid shifts, gradual spinal extension and movement of abdominal mass, and redistribution of circulatory impedance because of venous distention in the upper body and the collapse of veins in the lower body. In this project, the cardiovascular responses to changes in intraventricular hydrostatic pressure, in intravascular hydrostatic

  13. Skeletal response to simulated weightlessness - A comparison of suspension techniques

    Science.gov (United States)

    Wronski, T. J.; Morey-Holton, E. R.

    1987-01-01

    Comparisons are made of the skeletal response of rats subjected to simulated weightlessness by back or tail suspension. In comparison to pair-fed control rats, back-suspended rats failed to gain weight whereas tail-suspended rats exhibited normal weight gain. Quantitative bone histomorphometry revealed marked skeletal abnormalities in the proximal tibial metaphysis of back-suspended rats. Loss of trabecular bone mass in these animals was due to a combination of depressed longitudinal bone growth, decreased bone formation, and increased bone resorption. In contrast, the proximal tibia of tail-suspended rats was relatively normal by these histologic criteria. However, a significant reduction trabecular bone volume occurred during 2 weeks of tail suspension, possibly due to a transient inhibition of bone formation. The findings indicate that tail suspension may be a more appropriate model for evaluating the effects of simulated weightlessness on skeletal homeostasis.

  14. Prolonged weightlessness, reference frames and visual symmetry detection.

    Science.gov (United States)

    Leone, G; de Schonen, S; Lipshits, M

    1998-01-01

    We evaluated the influence of prolonged weightlessness on the performance of three cosmonauts to bilateral symmetry detection in the course of a 15-day-long Russian-French mission CASSIOPEE 96 aboard the MIR station. We tested the influence of weightlessness on subjects' performance as a function of the retinal orientation of axis of symmetry. as a function of type of stimuli (closed versus multi-elements shapes) and as a function of visual field presentation (at fixation, left visual field. right visual field). The results indicate firstly a difference between presentation at fixation versus away of fixation. Away of fixation, no effect of microgravity on performance was shown. A hypothesis of hemispheric specialization for symmetry detection was not supported as well. At fixation, an effect of micro-gravity was shown and more interestingly, the effect was quite different as a function of type of shapes used. suggesting that symmetry detection is a multiple-stage process.

  15. Effects of weightlessness on human fluid and electrolyte physiology

    Science.gov (United States)

    Leach, Carolyn S.; Johnson, Philip C., Jr.

    1991-01-01

    Skylab and Spacelab data on changes occurring in human fluid and electrolyte physiology during the acute and adaptive phases of adaptation to spaceflight are summarized. The combined results for all three Spacelab studies show that hyponatremia developed within 20 h after the onset of weightlessness and continued throughout the flights, and hypokalemia developed by 40 h. Antidiuretic hormone was increased in plasma throughout the flights. Aldosterone decreased by 40 h, but after 7 days it had reached preflight levels.

  16. A drop jumps to weightlessness: a lecture demo

    Science.gov (United States)

    Mayer, V. V.; Varaksina, E. I.; Saranin, V. A.

    2017-04-01

    The paper discusses the lecture demonstration of the phenomenon in which a drop lying on a solid unwettable substrate jumps when making the transition to weightlessness. An elementary theory of the phenomenon is given. A jump speed estimate is obtained for small and large drops. The natural vibrational frequency of a flying drop is determined. A full-scale model of Einstein’s elevator is described. Experimental and theoretical results are found to agree satisfactorily.

  17. A universal multilingual weightless neural network tagger via quantitative linguistics.

    Science.gov (United States)

    Carneiro, Hugo C C; Pedreira, Carlos E; França, Felipe M G; Lima, Priscila M V

    2017-07-01

    In the last decade, given the availability of corpora in several distinct languages, research on multilingual part-of-speech tagging started to grow. Amongst the novelties there is mWANN-Tagger (multilingual weightless artificial neural network tagger), a weightless neural part-of-speech tagger capable of being used for mostly-suffix-oriented languages. The tagger was subjected to corpora in eight languages of quite distinct natures and had a remarkable accuracy with very low sample deviation in every one of them, indicating the robustness of weightless neural systems for part-of-speech tagging tasks. However, mWANN-Tagger needed to be tuned for every new corpus, since each one required a different parameter configuration. For mWANN-Tagger to be truly multilingual, it should be usable for any new language with no need of parameter tuning. This article proposes a study that aims to find a relation between the lexical diversity of a language and the parameter configuration that would produce the best performing mWANN-Tagger instance. Preliminary analyses suggested that a single parameter configuration may be applied to the eight aforementioned languages. The mWANN-Tagger instance produced by this configuration was as accurate as the language-dependent ones obtained through tuning. Afterwards, the weightless neural tagger was further subjected to new corpora in languages that range from very isolating to polysynthetic ones. The best performing instances of mWANN-Tagger are again the ones produced by the universal parameter configuration. Hence, mWANN-Tagger can be applied to new corpora with no need of parameter tuning, making it a universal multilingual part-of-speech tagger. Further experiments with Universal Dependencies treebanks reveal that mWANN-Tagger may be extended and that it has potential to outperform most state-of-the-art part-of-speech taggers if better word representations are provided. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. [Effect of aerospace weightlessness on cognitive functions and the relative dialectical analysis of Chinese medicine].

    Science.gov (United States)

    Dong, Li; Liu, Xin-Min; Wu, Li-Sha; Yang, Si-Jin; Wang, Qiong

    2014-03-01

    Aerospace medicine has paid more and more attention to abnormal changes of physiological functions induced by weightlessness and studies on their prevention during space flight. In this paper, the effect of space weightlessness on cognitive functions was introduced. We tried to analyze the correlation between the cognitive function changes and relevant Chinese medical syndromes, thus providing a potential available way to prevent and treat weightlessness induced cognitive deficit during space flight.

  19. Physiological responses to environmental factors related to space flight. [hemodynamic and metabolic responses to weightlessness

    Science.gov (United States)

    Pace, N.

    1973-01-01

    Physiological base line data are established, and physiological procedures and instrumentation necessary for the automatic measurement of hemodynamic and metabolic parameters during prolonged periods of weightlessness are developed.

  20. Thought Experiments in Teaching Free-Fall Weightlessness: A Critical Review and an Exploration of Mercury's Behavior in "Falling Elevator"

    Science.gov (United States)

    Balukovic, Jasmina; Slisko, Josip; Cruz, Adrián Corona

    2017-01-01

    Different "thought experiments" dominate teaching approaches to weightlessness, reducing students' opportunities for active physics learning, which should include observations, descriptions, explanations and predictions of real phenomena. Besides the controversy related to conceptual definitions of weight and weightlessness, we report…

  1. Thought Experiments in Teaching Free-Fall Weightlessness: A Critical Review and an Exploration of Mercury's Behavior in "Falling Elevator"

    Science.gov (United States)

    Balukovic, Jasmina; Slisko, Josip; Cruz, Adrián Corona

    2017-01-01

    Different "thought experiments" dominate teaching approaches to weightlessness, reducing students' opportunities for active physics learning, which should include observations, descriptions, explanations and predictions of real phenomena. Besides the controversy related to conceptual definitions of weight and weightlessness, we report…

  2. EFFECT OF SIMULATED WEIGHTLESSNESS ON REPRODUCTION OF ADULT MALE RATS

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Numerous studies had mainly focused on thehar mful effects of space environment on human be-ing's muscle,skeleton and blood circulation[1-3].However,the studies concerningthe effects of spaceenvironment on male reproduction are scare.The space environment is complicated,andweightlessness is one of the most i mportant healthrisk factors.Tail-suspension model is widely usedfor si mulated weightlessness in space health re-search[4].Therefore,the present study was designed toclarify the adverse effects of si mu...

  3. The use of suspension models and comparison with true weightlessness. [Animal Model Workshop on Gravitational Physiology

    Science.gov (United States)

    Musacchia, X. J.; Ellis, S.

    1985-01-01

    A resume is presented of various papers concerning the effect of weightlessness on particular physiological and biochemical phenomena in animal model systems. Findings from weightlessness experiments on earth using suspension models are compared with results of experiments in orbit. The biological phenomena considered include muscle atrophy, changes in the endocrine system, reduction in bone formation, and changes in the cardiovascular system.

  4. A systems analysis of the erythropoietic responses to weightlessness. Volume 1: Mathematical model simulations of the erythropoietic responses to weightlessness

    Science.gov (United States)

    Leonard, J. I.

    1985-01-01

    Theoretical responses to weightlessness are summarized. The studies include development and validation of a model of erythropoiesis regulation, analysis of the behavior of erythropoiesis under a variety of conditions, simulations of bed rest and space flight, and an evaluation of ground-based animal studies which were conducted as analogs of zero-g. A review of all relevant space flight findings and a set of testable hypotheses which attempt to explain how red cell mass decreases in space flight are presented. An additional document describes details of the mathematical model used in these studies.

  5. Musculoskeletal adaptations to weightlessness and development of effective countermeasures

    Science.gov (United States)

    Baldwin, K. M.; White, T. P.; Arnaud, S. B.; Edgerton, V. R.; Kraemer, W. J.; Kram, R.; Raab-Cullen, D.; Snow, C. M.

    1996-01-01

    A Research Roundtable, organized by the American College of Sports Medicine with sponsorship from the National Aeronautics and Space Administration, met in November 1995 to define research strategies for effective exercise countermeasures to weightlessness. Exercise was considered both independently of, and in conjunction with, other therapeutic modalities (e.g., pharmacological nutritional, hormonal, and growth-related factors) that could prevent or minimize the structural and functional deficits involving skeletal muscle and bone in response to chronic exposure to weightlessness, as well as return to Earth baseline function if a degree of loss is inevitable. Musculoskeletal deficits and countermeasures are described with respect to: 1) muscle and connective tissue atrophy and localized bone loss, 2) reductions in motor performance, 3) potential proneness to injury of hard and soft tissues, and 4) probable interaction between muscle atrophy and cardiovascular alterations that contribute to the postural hypotension observed immediately upon return from space flight. In spite of a variety of countermeasure protocols utilized previously involving largely endurance types of exercise, there is presently no activity-specific countermeasure(s) that adequately prevent or reduce musculoskeletal deficiencies. It seems apparent that countermeasure exercises that have a greater resistance element, as compared to endurance activities, may prove beneficial to the musculoskeletal system. Many questions remain for scientific investigation to identify efficacious countermeasure protocols, which will be imperative with the emerging era of long-term space flight.

  6. [The development OF THE vestibular apparatus under conditions of weightlessness].

    Science.gov (United States)

    Vinikov, Ia A; Gazenko, O G; Titovo, L K; Bornshteĭn, A A; Govardovskiĭ, V I

    1976-01-01

    The spawn of the aquarium fish Brachydanio rerio was developing during 5--6 days under conditions of weightlessness (first on board the spaceship "Sojuz-16", then in the space station "Salut-4") in special aquariums "EMKON", in thermostable installations. Electron microscopically the embryos were found to have a well developed labyrinth in early developmental histologically and cytologically differentiated receptory structures of the macula utriculi and macula saccili. In contrast to controls, the experimental animals showed certain alterations in the otolite organization. In similar experiments the embryos of clawed frog Xenopus laevis in the stage of the tail bud were also placed in special containers "EMKON" and thermostable apparatus "Biotherm-4" and by the spaceship "Sojuz-17" were brought to the space station "Salut-4", where it stayed for 16 days. The initial embryos had already had a well developed acoustic vesicle with macula communis. Inspite of the preliminary load by start acceleration and staying under conditions of weightlessness, they reached the general development fairly similar to controls. As it was shown electron microscopically their labyrinth had highly histologically and cytologically differentiated structures. However, a disturbance of the development of the otolithic membrane and otoconia should be noted. The alterations observed in the otolithic membrane organization in experimental fishes and frogs may be explained by general disorders in calcium metabolism.

  7. Effect of weightlessness on colloidal particle transport and segregation in self-organising microtubule preparations.

    Science.gov (United States)

    Tabony, James; Rigotti, Nathalie; Glade, Nicolas; Cortès, Sandra

    2007-05-01

    Weightlessness is known to effect cellular functions by as yet undetermined processes. Many experiments indicate a role of the cytoskeleton and microtubules. Under appropriate conditions in vitro microtubule preparations behave as a complex system that self-organises by a combination of reaction and diffusion. This process also results in the collective transport and organisation of any colloidal particles present. In large centimetre-sized samples, self-organisation does not occur when samples are exposed to a brief early period of weightlessness. Here, we report both space-flight and ground-based (clinorotation) experiments on the effect of weightlessness on the transport and segregation of colloidal particles and chromosomes. In centimetre-sized containers, both methods show that a brief initial period of weightlessness strongly inhibits particle transport. In miniature cell-sized containers under normal gravity conditions, the particle transport that self-organisation causes results in their accumulation into segregated regions of high and low particle density. The gravity dependence of this behaviour is strongly shape dependent. In square wells, neither self-organisation nor particle transport and segregation occur under conditions of weightlessness. On the contrary, in rectangular canals, both phenomena are largely unaffected by weightlessness. These observations suggest, depending on factors such as cell and embryo shape, that major biological functions associated with microtubule driven particle transport and organisation might be strongly perturbed by weightlessness.

  8. Skeletal Micro-RNA Responses to Simulated Weightlessness

    Science.gov (United States)

    Thomas, Nicholas J.; Choi, Catherine Y.; Alwood, Joshua S.

    2016-01-01

    Astronauts lose bone structure during long-duration spaceflight. These changes are due, in part, to insufficient bone formation by the osteoblast cells. Little is known about the role that small (approximately 22 nucleotides), non-coding micro-RNAs (miRNAs) play in the osteoblast response to microgravity. We hypothesize that osteoblast-lineage cells alter their miRNA status during microgravity exposure, contributing to impaired bone formation during weightlessness. To simulate weightlessness, female mice (C57BL/6, Charles River, 10 weeks of age, n = 7) were hindlimb unloaded up to 12 days. Age-matched and normally ambulating mice served as controls (n=7). To assess the expression of miRNAs in skeletal tissue, the tibia was collected ex vivo and cleaned of soft-tissue and marrow. Total RNA was collected from tibial bone and relative abundance was measured for miRNAs of interest using quantitative real time PCR array looking at 372 unique and well-characterized mature miRNAs using the delta-delta Ct method. Transcripts of interest were normalized to an average of 6 reference RNAs. Preliminary results show that hindlimb unloading decreased the expression of 14 miRNAs to less than 0.5 times that of the control levels and increased the expression of 5 miRNAs relative to the control mice between 1.2-1.5-fold (p less than 0.05, respectively). Using the miRSystem we assessed overlapping target genes predicted to be regulated by multiple members of the 19 differentially expressed miRNAs as well as in silico predicted targets of our individual miRNAs. Our miRsystem results indicated that a number of our differentially expressed miRNAs were regulators of genes related to the Wnt-Beta Catenin pathway-a known regulator of bone health-and, interestingly, the estrogen-mediated cell-cycle regulation pathway, which may indicate that simulated weightlessness modulated systemic hormonal levels or hormonal transduction that additionally contributed to bone loss. We plan to follow up

  9. Biomechanics of running in weightlessness on a treadmill equipped with a subject loading system

    OpenAIRE

    Gosseye, Thierry

    2011-01-01

    One countermeasure used during long duration spaceflight to maintain bone and muscle mass is a treadmill equipped with a subject loading system (SLS) that simulates gravity. To date, little is known about the biomechanics of running in weightlessness on such a treadmill-SLS system. We have designed an instrumented treadmill/force-plate to compare the biomechanics of running in weightlessness to running on Earth. Gravity was simulated by two pneumatic pistons pulling downwards on a subject’s h...

  10. Second All-Union Seminar on Hydromechanics and Heat-Mass Transfer in Weightlessness. Abstracts of reports: Table of contents

    Science.gov (United States)

    Gershuni, G. Z.; Zhukhovitskiy, Y. M.

    1984-01-01

    Abstracts of reports are given which were presented at the Second All Union Seminar on Hydromechanics and Heat-Mass Transfer in Weightlessness. Topics inlcude: (1) features of crystallization of semiconductor materials under conditions of microacceleration; (2) experimental results of crystallization of solid solutions of CDTE-HGTE under conditions of weightlessness; (3) impurities in crystals cultivated under conditions of weightlessness; and (4) a numerical investigation of the distribution of impurities during guided crystallization of a melt.

  11. Dual Matter-Wave Inertial Sensors in Weightlessness

    CERN Document Server

    Barrett, Brynle; Chichet, Laure; Battelier, Baptiste; Lévèque, Thomas; Landragin, Arnaud; Bouyer, Philippe

    2016-01-01

    Quantum technology based on cold-atom interferometers is showing great promise for fields such as inertial sensing and fundamental physics. However, the best precision achievable on Earth is limited by the free-fall time of the atoms, and their full potential can only be realized in Space where interrogation times of many seconds will lead to unprecedented sensitivity. Various mission scenarios are presently being pursued which plan to implement matter-wave inertial sensors. Toward this goal, we realize the first onboard operation of simultaneous $^{87}$Rb $-$ $^{39}$K interferometers in the weightless environment produced during parabolic flight. The large vibration levels ($10^{-2}~g/\\sqrt{\\rm Hz}$), acceleration range ($0-1.8~g$) and rotation rates ($5$ deg/s) during flight present significant challenges. We demonstrate the capability of our dual-quantum sensor by measuring the E\\"{o}tv\\"{o}s parameter with systematic-limited uncertainties of $1.1 \\times 10^{-3}$ and $3.0 \\times 10^{-4}$ during standard- a...

  12. Postnatal development under conditions of simulated weightlessness and space flight

    Science.gov (United States)

    Walton, K.

    1998-01-01

    The adaptability of the developing nervous system to environmental influences and the mechanisms underlying this plasticity has recently become a subject of interest in space neuroscience. Ground studies on neonatal rats using the tail suspension model of weightlessness have shown that the force of gravity clearly influences the events underlying the postnatal development of motor function. These effects depend on the age of the animal, duration of the perturbation and the motor function studied. A nine-day flight study has shown that a dam and neonates can develop under conditions of space flight. The motor function of the flight animals after landing was consistent with that seen in the tail suspension studies, being marked by limb joint extension. However, there were expected differences due to: (1) the unloading of the vestibular system in flight, which did not occur in the ground-based experiments; (2) differences between flight and suspension durations; and (3) the inability to evaluate motor function during the flight. The next step is to conduct experiments in space with the flexibility and rigor that is now limited to ground studies: an opportunity offered by the International Space Station. Copyright 1998 Published by Elsevier Science B.V.

  13. Response to muscular exercise following repeated simulated weightlessness

    Science.gov (United States)

    Convertino, V. A.; Kirby, C. R.; Karst, G. M.; Goldwater, D. J.

    1985-01-01

    The effects of 10-d 6-deg-head-down bed rest (BR1), 14 d of recovery, another 10 d bed rest (BR2), and another 14-d recovery on the cardiovascular response to a graded supine cycle ergometer test (4 min unloaded 60-rpm pedaling followed by 15-W/min increasing work load to volitional fatigue) are investigated experimentally in seven male nonsmokers of mean age 41 yrs, mean weight 80.2 kg, mean height 178 cm, and mean body fat content 22.3 percent. Ergometer tests are performed before BR1, after BR1 and BR2, and 14 d after BR2. The results are presented in tables, and it is found that the significantly decreased maximum-O2-uptake, gas-exchange-aerobic-threshold, and plasma-volume responses and the increased submaximal and maximal heart rates observed (relative to pre-BR1 levels) after BR1 and BR2 return to pre-BR1 values 14 d after BR2. It is inferred that 14 d of mild exercise are adequate for recovery from even repeated exposure to this type of simulated weightlessness.

  14. Mechanism for negative water balance during weightlessness An hypothesis

    Science.gov (United States)

    Greenleaf, J. E.

    1986-01-01

    The mechanism for the apparent decrease in body fluid volume in astronauts during spaceflight remains obscure. The widespread postulate that the hypohydration is the result of the Henry-Gauer reflex, a diuresis caused by inhibition of vasopressin secretion resulting from increased left and perhaps right atrial (central) venous pressure, has not been established with direct measurements on astronauts. An hypothesis is proposed to account for fluid-electrolyte shifts during weightlessness. A moderate but transient increase in central venous pressure occurs when orbit is entered that is insufficient to activate the Henry-Gauer reflex but sufficient to stimulate the release of atrial natriuretic peptides. Increased sodium excretion would facilitate some increased urinary water loss. The resulting relatively dilute plasma and interstitial fluids would cause fluid to shift into the cellular space, resulting in edema in the head and trunk and inhibition of thirst and drinking. Thus, the negative water balance in astronauts would be caused by a gradual natriuresis and diuresis coupled with reduced fluid intake.

  15. Residual nutational activity of the sunflower hypocotyl in simulated weightlessness

    Science.gov (United States)

    Chapman, D. K.; Brown, A. H.

    1979-01-01

    The gravity dependence of circumnutational activity in the sunflower hypocotyl is investigated under conditions of simulated weightlessness. Seedling cultures of the sunflower Helianthus annuus were placed four days after planting in clinostats rotating at a rate of 1.0 rpm in the horizontal or somersaulting configurations, and plant movements around their growth axes were recorded in infrared light by a time-lapse closed-circuit video system. The amplitudes and mean cycle durations of the plant nutations in the horizontal and tumbling clinostats are observed to be 20% and 72%, and 32% and 74%, respectively, of the values observed in stationary plants; extrapolations to a state of zero g by the imposition of small centripetal forces on horizontally clinostated plants also indicate some nutational motion in the absence of gravity. It is concluded that the results are incompatible with the model of Israelsson and Johnsson (1967) of geotropic response with overshoot for sunflower circumnutation; however, results of the Spacelab 1 mission experiment are needed to unambiguously define the role of gravitation.

  16. Dual matter-wave inertial sensors in weightlessness

    Science.gov (United States)

    Barrett, Brynle; Antoni-Micollier, Laura; Chichet, Laure; Battelier, Baptiste; Lévèque, Thomas; Landragin, Arnaud; Bouyer, Philippe

    2016-12-01

    Quantum technology based on cold-atom interferometers is showing great promise for fields such as inertial sensing and fundamental physics. However, the finite free-fall time of the atoms limits the precision achievable on Earth, while in space interrogation times of many seconds will lead to unprecedented sensitivity. Here we realize simultaneous 87Rb-39K interferometers capable of operating in the weightless environment produced during parabolic flight. Large vibration levels (10-2 g Hz-1/2), variations in acceleration (0-1.8 g) and rotation rates (5° s-1) onboard the aircraft present significant challenges. We demonstrate the capability of our correlated quantum system by measuring the Eötvös parameter with systematic-limited uncertainties of 1.1 × 10-3 and 3.0 × 10-4 during standard- and microgravity, respectively. This constitutes a fundamental test of the equivalence principle using quantum sensors in a free-falling vehicle. Our results are applicable to inertial navigation, and can be extended to the trajectory of a satellite for future space missions.

  17. Effect of 5E Teaching Model on Student Teachers' Understanding of Weightlessness

    Science.gov (United States)

    Tural, Güner; Akdeniz, Ali Rıza; Alev, Nedim

    2010-10-01

    Weight is one of the basic concepts of physics. Its gravitational definition accommodates difficulties for students to understand the state of weightlessness. The aim of this study is to investigate the effect of materials based on 5E teaching model and related to weightlessness on science student teachers' learning. The sample of the study was 9 volunteer student teachers who were in their first grade in Science Teaching Program in Fatih Faculty of Education, Karadeniz Technical University. Both qualitative and quantitative data were gathered to find answers to the research questions. Findings revealed that all physics textbooks reviewed gave gravitational definition of weight. Also the concept of weightlessness hasn't been covered in high school and some university textbooks. It was determined that before the implementation student teachers had non-scientific explanations about weightlessness. The implementation of the 5E teaching model and materials developed are effective on learning the weightlessness. It is suggested that similar applications can also be used in other physics subjects or in other fields of science.

  18. Alterations in gut transport of minerals and in binding proteins during simulated weightlessness

    Science.gov (United States)

    Bikle, D. D.

    1984-01-01

    The structural components of the skeleton develop and are maintained in a 1 g environment, shaped by the mechanical load to which they are constantly exposed. Altering such a mechanical load by reducing the gravitational force imposed on the system, as in space flight, has profound effects on the skeleton and permits an exploration of the molecular events which regulate normal skeletal homeostasis. The objective was to determine whether simulated weightlessness reduced intestinal calcium transport, and if so, to determine the molecular mechanisms for such an effect. A nonstressful tail suspension in which the rats gained weight normally while suspended was used to simulate weightlessness. A significant change in intestinal calcium transport was not demonstrated. However, a cyclic change in bone formation with suspension was shown. Based on these observations, the objective changed to determination of the hormonal regulation of bone formation during simulated weightlessness.

  19. Simulated Space Radiation and Weightlessness: Vascular-Bone Coupling Mechanisms to Preserve Skeletal Health

    Science.gov (United States)

    Alwood, J. S.; Limoli, C. L.; Delp, M. D.; Castillo, A. B.; Globus, R. K.

    2012-01-01

    Weightlessness causes a cephalad fluid shift and reduction in mechanical stimulation, adversely affecting both cortical and trabecular bone tissue in astronauts. In rodent models of weightlessness, the onset of bone loss correlates with reduced skeletal perfusion, reduced and rarified vasculature and lessened vasodilation, which resembles blood-bone symbiotic events that can occur with fracture repair and aging. These are especially serious risks for long term, exploration class missions when astronauts will face the challenge of increased exposure to space radiation and abrupt transitions between different gravity environments upon arrival and return. Previously, we found using the mouse hindlimb unloading model and exposure to heavy ion radiation, both disuse and irradiation cause an acute bone loss that was associated with a reduced capacity to produce bone-forming osteoblasts from the bone marrow. Together, these findings led us to hypothesize that exposure to space radiation exacerbates weightlessness-induced bone loss and impairs recovery upon return, and that treatment with anti-oxidants may mitigate these effects. The specific aims of this recently awarded grant are to: AIM 1 Determine the functional and structural consequences of prolonged weightlessness and space radiation (simulated spaceflight) for bone and skeletal vasculature in the context of bone cell function and oxidative stress. AIM 2 Determine the extent to which an anti-oxidant protects against weightlessness and space radiation-induced bone loss and vascular dysfunction. AIM 3 Determine how space radiation influences later skeletal and vasculature recovery from prolonged weightlessness and the potential of anti-oxidants to preserve adaptive remodeling.

  20. Electromyographic analysis of skeletal muscle changes arising from 9 days of weightlessness in the Apollo-Soyuz space mission

    Science.gov (United States)

    Lafevers, E. V.; Nicogossian, A. E.; Hursta, W. N.

    1976-01-01

    Both integration and frequency analyses of the electromyograms from voluntary contractions were performed in one crewman of the Apollo-Soyuz Test Project mission. Of particular interest were changes in excitability, electrical efficiency, and fatigability. As a result of 9 days of weightlessness, muscle excitability was shown to increase; muscle electrical efficiency was found to decrease in calf muscles and to increase in arm muscles; and fatigability was found to increase significantly, as shown by spectral power shifts into lower frequencies. It was concluded from this study that skeletal muscles are affected by the disuse of weightlessness early in the period of weightlessness, antigravity muscles seem most affected by weightlessness, and exercise may abrogate the weightlessness effect. It was further concluded that electromyography is a sensitive tool for measuring spaceflight muscle effects.

  1. Influence of proprioceptive information on space orientation on the ground and in orbital weightlessness

    Science.gov (United States)

    von Baumgarten, R.; Kass, J.; Vogel, H.; Wetzig, J.

    Conscious space orientation depends on afferent information from different sense organs including the labyrinth, the eyes, tactile cues from the skin, joint receptors, muscle spindles, tendon organs and possibly viscera. An important role is played by impulses from the cervical position receptors in interaction with concomitant information from the otolith system. In order to isolate the effect of cervical position receptors from that of the otolith system, space experiments in orbital weightlessness and in parabolic aircraft flight were performed. It was found that stimulation of the neck receptors in weightlessness markedly influences the perception of the subjective vertical and horizontal and in addition has a weak effect on ocular torsion.

  2. Pine seed germination under weightlessness (a study of the Kosmos 782 satellite)

    Science.gov (United States)

    Platonova, R. N.; Parfenov, G. P.; Olkhovenko, V. P.; Karpova, N. I.; Pichugov, M. Y.

    1977-01-01

    Orientation of the above and underground organs of pine plants, grown from seeds under weightlessness, was found to be determined by seed position on the substrate. Normal plant growth was observed only if the seed embryos were oriented toward the substrate. Some differences were noted between the experimental and control plants concerning the amount of nucleoli in the root meristematic cells and the cell shape in cotyledonous leaves. No complete similarity was found in experimental results obtained with plants under weightlessness and under compensated gravity. The seeds were obtained from Pinus silvestris, considered to be particularly suitable for this experiment.

  3. Cardiovascular adaptations in weightlessness: The influence of in-flight exercise programs on the cardiovascular adjustments during weightlessness and upon returning to Earth

    Science.gov (United States)

    Bennett, C. H.

    1981-01-01

    The effect of in-flight exercise programs on astronauts' cardiovascular adjustments during spaceflight weightlessness and upon return to Earth was studied. Physiological changes in muscle strength and volume, cardiovascular responses during the application of lower body negative pressure, and metabolic activities during pre-flight and flight tests were made on Skylab crewmembers. The successful completion of the Skylab missions showed that man can perform submaximal and maximal aerobic exercise in the weightless enviroment without detrimental trends in any of the physiologic data. Exercise tolerance during flight was unaffected. It was only after return to Earth that a tolerance decrement was noted. The rapid postflight recovery of orthostatic and exercise tolerance following two of the three Skylab missions appeared to be directly related to total in-flight exercise as well as to the graded, regular program of exercise performed during the postflight debriefing period.

  4. The Effect of Part-simulation of Weightlessness on Human Control of Bilateral Teleoperation: Neuromotor Considerations

    Science.gov (United States)

    Corker, K.; Bejczy, A. K.

    1984-01-01

    The effect of weightlessness on the human operator's performance in force reflecting position control of remote manipulators was investigated. A gravity compensation system was developed to simulate the effect of weightlessness on the operator's arm. A universal force reflecting hand controller (FRHC) and task simulation software were employed. Two experiments were performed because of anticipated disturbances in neuromotor control specification on the human operator in an orbital control environment to investigate: (1) the effect of controller stiffness on the attainment of a learned terminal position in the three dimensional controller space, and (2) the effect of controller stiffness and damping on force tracking of the contour of a simulated three dimensional cube using the part simulation of weightless conditions. The results support the extension of neuromotor control models, which postulate a stiffness balance encoding of terminal position, to three dimensional motion of a multilink system, confirm the existence of a disturbance in human manual control performance under gravity compensated conditions, and suggest techniques for compensation of weightlessness induced performance decrement through appropriate specification of hand controller response characteristics. These techniques are based on the human control model.

  5. [Effect of weightlessness and movement restraint on structure and metabolism of M. soleus in monkeys after space flight].

    Science.gov (United States)

    Shenkman, B S; Belozerova, I N; Lee, P; Nemirovskaia, T L; Kozlovskaia, I B

    2002-03-01

    After staying in real and simulated weightlessness, the most obvious changes were recorded in the "slow" tonic muscles like m. soleus, the protein loss in the fibres being greater than the loss of other components, water included.

  6. Correlation between vestibular sensitization and leg muscle relaxation under weightlessness simulated by water immersion.

    Science.gov (United States)

    Mitarai, G; Mano, T; Yamazaki, Y

    1981-01-01

    The experiments were designed to determine the contribution of the leg muscle relaxation to the sensitization of the vestibular function under weightlessness, The neuromuscular unit (NMU) discharges were continuously recorded with microelectrodes from the anti-gravitational soleus muscle and its antagonist, the tibialis anterior, of a man standing first upright on the level floor of a dry water tank, and then gradually being immersed in water till it reached his neck; while he was buoyed with an airtube placed under his armpit. In each of the successive states, the caloric nystagmus was evoked, analyzed and compared with the NMU discharge as well as with subjective symptoms associated with the nystagmus. The results indicate that the nystagmogenic activity had a significant correlation with the appearance of the active NMU in the soleus, and they also suggest that the reduction of ascending signals from the antigravity muscles might be one of the causes of atypical vestibular responses occuring in weightlessness.

  7. Skeletal muscle atrophy in response to 14 days of weightlessness - Vastus medialis

    Science.gov (United States)

    Musacchia, X. J.; Steffen, J. M.; Fell, R. D.; Dombrowski, M. J.; Oganov, V. W.; Il'ina-Kakueva, E. I.

    1992-01-01

    The vastus medialis (VM) response from rats after 14 days of microgravity on Cosmos 2044 (F) have been studied by comparing it with VM from tail-suspended hindlimb-unloaded rats (T) and ground controls. The experimental approaches encompassed a histochemical evaluation of microscopic morphology, including fibers and capillaries; an assessment of biochemical composition including protein, DNA, and RNA concentrations; and an estimation of metabolic capacity. It is concluded that some significant changes were observed in the VM in rats exposed to weightlessness for 14 days. There is a loss in weight compared with the vivarium controls but not in comparison with synchronous and basal controls. Although there were minimal muscle weight differences between groups, muscle weight may be a less sensitive measure of change or atrophy than fiber area measurements. It is suggested that the nonload-bearing muscles, including the VM, show measurable responses to weightless flight.

  8. Evaluation of the response of rat skeletal muscle to a model of weightlessness

    Science.gov (United States)

    Templeton, G. H.; Padalino, M.; Glasberg, M.; Manton, J.; Silver, P.; Sutko, J.

    1982-01-01

    Suspension of rats in a head-down tilt position such that their hind limbs are non-load bearing has been proposed as a model for weightlessness. Changes observed in metabolism, bone formation (Morey et al., 1979), and muscle catabolism (Mussachia et al., 1980) support the validity of the model. To further document this model, the effects of suspension on the mechanical, biochemical and histochemical characteristics of two hind limb skeletal muscles, the gastrocnemius and the soleus, are investigated.

  9. Potential benefits of maximal exercise just prior to return from weightlessness

    Science.gov (United States)

    Convertino, Victor A.

    1987-01-01

    The purpose of this study was to determine whether performance of a single maximal bout of exercise during weightlessness within hours of return to earth would enhance recovery of aerobic fitness and physical work capacities under a 1G environment. Ten healthy men were subjected to a 10-d bedrest period in the 6-deg headdown position. A graded maximal supine cycle ergometer test was performed before and at the end of bedrest to simulate exercise during weightlessness. Following 3 h of resumption of the upright posture, a second maximal exercise test was performed on a treadmill to measure work capacity under conditions of 1G. Compared to before bedrest, peak oxygen consumption, V(O2), decreased by 8.7 percent and peak heart rate (HR) increased by 5.6 percent in the supine cycle test at the end of bedrest. However, there were no significant changes in peak V(O2) and peak HR in the upright treadmill test following bedrest. These data suggest that one bout of maximal leg exercise prior to return from 10 d of weightlessness may be adequate to restore preflight aerobic fitness and physical work capacity.

  10. Evaluation of the three-dimensional clinostat as a simulator of weightlessness.

    Science.gov (United States)

    Hoson, T; Kamisaka, S; Masuda, Y; Yamashita, M; Buchen, B

    1997-01-01

    Concerns regarding the reliability of slow-and fast-rotating uni-axial clinostats in simulating weightlessness have induced the construction of devices considered to simulate weightlessness more adequately. A new three-dimensional (3-D) clinostat equipped with two rotation axes placed at right angles has been constructed. In the clinostat, the rotation achieved with two motors is computer-controlled and monitored with encoders attached to the motors. By rotating plants three-dimensionally at random rates on the clinostat, their dynamic stimulation by gravity in every direction can be eliminated. Some of the vegetative growth phases of plants dependent on the gravity vector, such as morphogenesis, are shown to be influenced by rotation on the 3-D clinostat. The validity of 3-D clinostatting has been evaluated by comparing structural parameters of cress roots and Chara rhizoids obtained under real microgravity with those obtained after 3-D clinostatting. The parameters analyzed up to now (organization of the root cap, integrity and polarity of statocytes, dislocation of statoliths, amount of starch and ER) demonstrate that the 3-D clinostat is a valuable device for simulating weightlessness.

  11. Perception of Affordance during Short-Term Exposure to Weightlessness in Parabolic Flight.

    Science.gov (United States)

    Bourrelly, Aurore; McIntyre, Joseph; Morio, Cédric; Despretz, Pascal; Luyat, Marion

    2016-01-01

    We investigated the role of the visual eye-height (VEH) in the perception of affordance during short-term exposure to weightlessness. Sixteen participants were tested during parabolic flight (0g) and on the ground (1g). Participants looked at a laptop showing a room in which a doorway-like aperture was presented. They were asked to adjust the opening of the virtual doorway until it was perceived to be just wide enough to pass through (i.e., the critical aperture). We manipulated VEH by raising the level of the floor in the visual room by 25 cm. The results showed effects of VEH and of gravity on the perceived critical aperture. When VEH was reduced (i.e., when the floor was raised), the critical aperture diminished, suggesting that widths relative to the body were perceived to be larger. The critical aperture was also lower in 0g, for a given VEH, suggesting that participants perceived apertures to be wider or themselves to be smaller in weightlessness, as compared to normal gravity. However, weightlessness also had an effect on the subjective level of the eyes projected into the visual scene. Thus, setting the critical aperture as a fixed percentage of the subjective visual eye-height remains a viable hypothesis to explain how human observers judge visual scenes in terms of potential for action or "affordances".

  12. Perception of Affordance during Short-Term Exposure to Weightlessness in Parabolic Flight

    Science.gov (United States)

    Bourrelly, Aurore; McIntyre, Joseph; Morio, Cédric; Despretz, Pascal; Luyat, Marion

    2016-01-01

    We investigated the role of the visual eye-height (VEH) in the perception of affordance during short-term exposure to weightlessness. Sixteen participants were tested during parabolic flight (0g) and on the ground (1g). Participants looked at a laptop showing a room in which a doorway-like aperture was presented. They were asked to adjust the opening of the virtual doorway until it was perceived to be just wide enough to pass through (i.e., the critical aperture). We manipulated VEH by raising the level of the floor in the visual room by 25 cm. The results showed effects of VEH and of gravity on the perceived critical aperture. When VEH was reduced (i.e., when the floor was raised), the critical aperture diminished, suggesting that widths relative to the body were perceived to be larger. The critical aperture was also lower in 0g, for a given VEH, suggesting that participants perceived apertures to be wider or themselves to be smaller in weightlessness, as compared to normal gravity. However, weightlessness also had an effect on the subjective level of the eyes projected into the visual scene. Thus, setting the critical aperture as a fixed percentage of the subjective visual eye-height remains a viable hypothesis to explain how human observers judge visual scenes in terms of potential for action or “affordances”. PMID:27097218

  13. Effect of simulated weightlessness and chronic 1,25-dihydroxyvitamin D administration on bone metabolism

    Science.gov (United States)

    Halloran, B. P.; Bikle, D. D.; Globus, R. K.; Levens, M. J.; Wronski, T. J.; Morey-Holton, E.

    1985-01-01

    Weightlessness, as experienced during space flight, and simulated weightlessness induce osteopenia. Using the suspended rat model to simulate weightlessness, a reduction in total tibia Ca and bone formation rate at the tibiofibular junction as well as an inhibition of Ca-45 and H-3-proline uptake by bone within 5-7 days of skeletal unloading was observed. Between days 7 and 15 of unloading, uptake of Ca-45 and H-3-proline, and bone formation rate return to normal, although total bone Ca remains abnormally low. To examine the relationship between these characteristic changes in bone metabolism induced by skeletal unloading and vitamin D metabolism, the serum concentrations of 25-hydroxyvitamin D (25-OH-D), 24, 25-dihydroxyvitamin D (24,25(OH)2D) and 1,25-dihydroxyvitamin D (1,25(OH)2D) at various times after skeletal unloading were measured. The effect of chronic infusion of 1,25(OH)2D3 on the bone changes associated with unloading was also determined.

  14. Cardiovascular, renal, electrolyte, and hormonal changes in man during gravitational stress, weightlessness, and simulated weightlessness: Lower body positive pressure applied by the antigravity suit. Thesis - Oslo Univ.

    Science.gov (United States)

    Kravik, Stein E.

    1989-01-01

    Because of their erect posture, humans are more vulnerable to gravitational changes than any other animal. During standing or walking man must constantly use his antigravity muscles and his two columns, his legs, to balance against the force of gravity. At the same time, blood is surging downward to the dependent portions of the body, draining blood away from the brain and heart, and requiring a series of complex cardiovascular adjustments to maintain the human in a bipedal position. It was not until 12 April 1961, when Yuri Gagarin became the first human being to orbit Earth, that we could confirm man's ability to maintain vital functions in space -- at least for 90 min. Nevertheless, man's adaptation to weightlessness entails the deconditioning of various organs in the body. Muscles atrophy, and calcium loss leads to loss of bone strength as the demands on the musculoskeletal system are almost nonexistent in weightlessness. Because of the lack of hydrostatic pressures in space, blood rushes to the upper portions of the body, initiating a complex series of cardioregulatory responses. Deconditioning during spaceflight, however, first becomes a potentially serious problem in humans returning to Earth, when the cardiovascular system, muscles and bones are suddenly exposed to the demanding counterforce of gravity -- weight. One of the main purposes of our studies was to test the feasibility of using Lower Body Positive Pressure, applied with an antigravity suit, as a new and alternative technique to bed rest and water immersion for studying cardioregulatory, renal, electrolyte, and hormonal changes in humans. The results suggest that Lower Body Positive Pressure can be used as an analog of microgravity-induced physiological responses in humans.

  15. Focused Assessment with Sonography for Trauma in weightlessness: a feasibility study

    Science.gov (United States)

    Kirkpatrick, Andrew W.; Hamilton, Douglas R.; Nicolaou, Savvas; Sargsyan, Ashot E.; Campbell, Mark R.; Feiveson, Alan; Dulchavsky, Scott A.; Melton, Shannon; Beck, George; Dawson, David L.

    2003-01-01

    BACKGROUND: The Focused Assessment with Sonography for Trauma (FAST) examines for fluid in gravitationally dependent regions. There is no prior experience with this technique in weightlessness, such as on the International Space Station, where sonography is currently the only diagnostic imaging tool. STUDY DESIGN: A ground-based (1 g) porcine model for sonography was developed. We examined both the feasibility and the comparative performance of the FAST examination in parabolic flight. Sonographic detection and fluid behavior were evaluated in four animals during alternating weightlessness (0 g) and hypergravity (1.8 g) periods. During flight, boluses of fluid were incrementally introduced into the peritoneal cavity. Standardized sonographic windows were recorded. Postflight, the video recordings were divided into 169 20-second segments for subsequent interpretation by 12 blinded ultrasonography experts. Reviewers first decided whether a video segment was of sufficient diagnostic quality to analyze (determinate). Determinate segments were then analyzed as containing or not containing fluid. A probit regression model compared the probability of a positive fluid diagnosis to actual fluid levels (0 to 500 mL) under both 0-g and 1.8-g conditions. RESULTS: The in-flight sonographers found real-time scanning and interpretation technically similar to that of terrestrial conditions, as long as restraint was maintained. On blinded review, 80% of the recorded ultrasound segments were considered determinate. The best sensitivity for diagnosis in 0 g was found to be from the subhepatic space, with probability of a positive fluid diagnosis ranging from 9% (no fluid) to 51% (500 mL fluid). CONCLUSIONS: The FAST examination is technically feasible in weightlessness, and merits operational consideration for clinical contingencies in space.

  16. Bion 11 Spaceflight Project: Effect of Weightlessness on Single Muscle Fiber Function in Rhesus Monkeys

    Science.gov (United States)

    Fitts, Robert H.; Romatowski, Janell G.; Widrick, Jeffrey J.; DeLaCruz, Lourdes

    1999-01-01

    Although it is well known that microgravity induces considerable limb muscle atrophy, little is known about how weightlessness alters cell function. In this study, we investigated how weightlessness altered the functional properties of single fast and slow striated muscle fibers. Physiological studies were carried out to test the hypothesis that microgravity causes fiber atrophy, a decreased peak force (Newtons), tension (Newtons/cross-sectional area) and power, an elevated peak rate of tension development (dp/dt), and an increased maximal shortening velocity (V(sub o)) in the slow type I fiber, while changes in the fast-twitch fiber are restricted to atrophy and a reduced peak force. For each fiber, we determined the peak force (P(sub o)), V(sub o), dp/dt, the force-velocity relationship, peak power, the power-force relationship, the force-pCa relationship, and fiber stiffness. Biochemical studies were carried out to assess the effects of weightlessness on the enzyme and substrate profile of the fast- and slow-twitch fibers. We predicted that microgravity would increase resting muscle glycogen and glycolytic metabolism in the slow fiber type, while the fast-twitch fiber enzyme profile would be unaltered. The increased muscle glycogen would in part result from an elevated hexokinase and glycogen synthase. The enzymes selected for study represent markers for mitochondrial function (citrate synthase and 0-hydroxyacyl-CoA dehydrogenase), glycolysis (Phosphofructokinase and lactate dehydrogenase), and fatty acid transport (Carnitine acetyl transferase). The substrates analyzed will include glycogen, lactate, adenosine triphosphate, and phosphocreatine.

  17. Influence of simulated weightlessness on the rate of anomalies of the flour beetle Tribolium confusum.

    Science.gov (United States)

    Briegleb, W; Neubert, J; Schatz, A; Sinapius, F

    1975-01-01

    Experiments with Tribolium confusum showed that the morphological characteristics of the beetles are modified by simulated weightlessness (fast running clinostat). Because of possible side effects due to differences in fertility of inbred lines, the first experiments were made with a genetically heterogeneous stock. Thereafter experiments were confirmed with inbred beetles. For both stocks a rise of mainly wing anomalies resulted from rotation of whole cultures of beetles within horizontal tubes. The extent to which these anomalies are teratogenetic or genetic has not yet been analysed in detail.

  18. [Effect of weightlessness on the functions of perception and the reproduction of gravitational vertical in response to optokinetic stimulation].

    Science.gov (United States)

    Sokolov, A I; Barmin, V A

    1988-01-01

    In weightlessness spatial orientation largely depends on coordinated interaction of sensory systems involved in static orientation. The purpose of the present study was to quantify perception of spatial coordinates in response to optokinetic stimulation. Effects of weightlessness were simulated by dry water immersion hypokinesia. A custom-made optokinetic stimulator equipped with a device to measure perception of the gravitational vertical in response to optokinetic stimulation was used. A special platform with rubber bungee cords was employed to determine the role of the proprioceptive afferent input. It was demonstrated that during immersion day 1 the angle of erroneous perception of the vertical line consistently increased. By immersion day 3 the angle diminished suggesting adaptive developments. Additional proprioceptive inflow during immersion reduced significantly the error of perception. These findings indicate that the proprioceptive afferent input plays an important role in the mechanisms of spatial orientation at an early stage of exposure to weightlessness.

  19. Effects of weightlessness and movement restriction on the structure and metabolism of the soleus muscle in monkeys after space flight.

    Science.gov (United States)

    Shenkman, B S; Belozerova, I N; Lee, Peter; Nemirovskaya, T L; Kozlovskaya, I B

    2003-09-01

    After humans and animals have been in conditions of real and modeled weightlessness, the most marked changes are seen in the "slow" tonic muscles, particularly soleus. Studies of the effects of weightlessness and movement restriction on the soleus muscle in monkeys demonstrated significant reductions in the sizes of slow and rapid fibers due mainly to the actions of real weightlessness (rather than movement restriction in the space capsule). Protein loss in soleus muscle fibers in monkeys following space flight was more marked than loss of other components, including water. The level of atrophy of soleus muscle fibers in these conditions was greater than the decrease in the number of capillaries. Succinate dehydrogenase activity in soleus muscle fibers decreased proportionally to the reduction in fiber size.

  20. Ground experiments for finding principles and working out methods for preventing adverse effects of weightlessness on the human organism

    Science.gov (United States)

    Kakurin, L. I.; Gregoryev, A. I.; Mikhailov, V. M.; Tishler, V. A.

    1980-01-01

    A comparative assessment of the effectiveness of different prophylactic procedures to prevent the adverse effects of weightlessness is presented. It is concluded that: physical training is most effective but no single method by itself produces the full effect, and an adjustment of regimes to one another enhances the effect. The approved complex of prophylactic procedures affected basic changes occurring in hypokinesia: deficit of muscular activity, no or reduced BP hydrostatic component, reduced volume of blood circulation, reduced hydration level, and the application of various prophylactic complexes during 49 day antiorthostatic hypodynamia eliminated or reduced the adverse effects of weightlessness in simulation.

  1. Selected contribution: redistribution of pulmonary perfusion during weightlessness and increased gravity

    Science.gov (United States)

    Glenny, R. W.; Lamm, W. J.; Bernard, S. L.; An, D.; Chornuk, M.; Pool, S. L.; Wagner, W. W. Jr; Hlastala, M. P.; Robertson, H. T.

    2000-01-01

    To compare the relative contributions of gravity and vascular structure to the distribution of pulmonary blood flow, we flew with pigs on the National Aeronautics and Space Administration KC-135 aircraft. A series of parabolas created alternating weightlessness and 1.8-G conditions. Fluorescent microspheres of varying colors were injected into the pulmonary circulation to mark regional blood flow during different postural and gravitational conditions. The lungs were subsequently removed, air dried, and sectioned into approximately 2 cm(3) pieces. Flow to each piece was determined for the different conditions. Perfusion heterogeneity did not change significantly during weightlessness compared with normal and increased gravitational forces. Regional blood flow to each lung piece changed little despite alterations in posture and gravitational forces. With the use of multiple stepwise linear regression, the contributions of gravity and vascular structure to regional perfusion were separated. We conclude that both gravity and the geometry of the pulmonary vascular tree influence regional pulmonary blood flow. However, the structure of the vascular tree is the primary determinant of regional perfusion in these animals.

  2. Perception of affordances during long-term exposure to weightlessness in the International Space station.

    Science.gov (United States)

    Bourrelly, Aurore; McIntyre, Joseph; Luyat, Marion

    2015-09-01

    On Earth, visual eye height (VEH)--the distance from the observer's line of gaze to the ground in the visual scene--constitutes an effective cue in perceiving affordance such as the passability through apertures, based on the assumption that one's feet are on the ground. In the present study, we questioned whether an observer continues to use VEH to estimate the width of apertures during long-term exposure to weightlessness, where contact with the floor is not required. Ten astronauts were tested in preflight, inflight in the International Space Station, and postflight sessions. They were asked to adjust the opening of a virtual doorway displayed on a laptop device until it was perceived to be just wide enough to pass through (i.e., the critical aperture). We manipulated VEH by raising and lowering the level of the floor in the visual scene. We observed an effect of VEH manipulation on the critical aperture. When VEH decreased, the critical aperture decreased too, suggesting that widths relative to the body were perceived to be larger when VEH was smaller. There was no overall significant session effect, but the analysis of between-subjects variability revealed two participant profile groups. The effect of weightlessness was different for these two groups even though the VEH strategy remained operational during spaceflight. This study shows that the VEH strategy appears to be very robust and can be used, if necessary, in inappropriate circumstances such as free-floating, perhaps promoted by the nature of the visual scene.

  3. Delineating the Impact of Weightlessness on Human Physiology Using Computational Models

    Science.gov (United States)

    Kassemi, Mohammad

    2015-01-01

    Microgravity environment has profound effects on several important human physiological systems. The impact of weightlessness is usually indirect as mediated by changes in the biological fluid flow and transport and alterations in the deformation and stress fields of the compliant tissues. In this context, Fluid-Structural and Fluid-Solid Interaction models provide a valuable tool in delineating the physical origins of the physiological changes so that systematic countermeasures can be devised to reduce their adverse effects. In this presentation, impact of gravity on three human physiological systems will be considered. The first case involves prediction of cardiac shape change and altered stress distributions in weightlessness. The second, presents a fluid-structural-interaction (FSI) analysis and assessment of the vestibular system and explores the reasons behind the unexpected microgravity caloric stimulation test results performed aboard the Skylab. The last case investigates renal stone development in microgravity and the possible impact of re-entry into partial gravity on the development and transport of nucleating, growing, and agglomerating renal calculi in the nephron. Finally, the need for model validation and verification and application of the FSI models to assess the effects of Artificial Gravity (AG) are also briefly discussed.

  4. The response of structure and function of the gravireceptor in a vertebrate to near weightlessness

    Science.gov (United States)

    Neubert, J.; Briegleb, W.; Schatz, A.; Hertwig, I.; Kruse, B.

    The paper sums up results of a 7-day space flight experiment (D-1-Mission-BW-STA 00-STATEX) using growing frog embryos and larvae ( Xenopus laevis) as a model system. Evaluation of photographs taken from the surface of sectioned deep-frozen objects, and micrographs using TEM and SEM show no aberrations in the shape, size, position, or respective electron density of the otolith membranes in larvae developed for 154 h under near-zero g. The further evaluation of the "weightless larvae" revealed a probably not yet described otolith-like formation below the dorsal wall of the vestibulum. In the weightless larvae this formation outnumbers, also qualitatively, strongly the 1- g control samples. The swimming behavior of the tadpoles which was observed about one hour after landing of the Space Shuttle showed a typical anomaly (loop swimming), which is known from larvae developed on the clinostat or from fish flown aboard Apollo capsules. An extra result is the lack of striking effects of cosmic radiation on the embryonic development of the flown Xenopus eggs.

  5. A unique problem of muscle adaptation from weightlessness: The deceleration deficiency

    Science.gov (United States)

    Stauber, William T.

    1989-01-01

    Decelerator problems of the knee are emphasized since the lower leg musculature is known to atrophy in response to weightlessness. However, other important decelerator functions are served by the shoulder muscles, in particular the rotator cuff muscles. Problems in these muscles often result in tears and dislocations as seen in baseball pitchers. It is noteworthy that at least one device currently exists that can measure concentric and eccentric muscle loading including a submaximal simulated free weight exercise (i.e., force-controlled) and simultaneously record integrated EMG analysis appropriate for assessment of all muscle functional activities. Studies should be undertaken to provide information as to the performance of maximal and submaximal exercise in space travelers to define potential problems and provide rationale for prevention.

  6. Effects of simulated weightlessness and sympathectomy on maximum VO2 of male rats

    Science.gov (United States)

    Woodman, C. R.; Stump, C. S.; Beaulieu, S. M.; Rahman, Z.; Sebastian, L. A.

    1989-01-01

    The effects of simulated weightlessness (hind-limb suspension) and chemical sympathectomy (by repeated injections with guanethidine sulfate) on the maximum oxygen consumption (VO2 max) of female rats were investigated in rats assigned for 14 days to one of three groups: a head-down hind-limb suspension, a horizontal suspension with hind limbs weight bearing, or the caged control. The VO2 max values were assessed by having rats run on a treadmill enclosed in an airtight chamber. The hind-limb-suspended sympathectomized rats were found to exhibit shorter run times and lower mechanical efficiencies, compared to their presuspension values or the values from saline-injected suspended controls. On the other hand, the suspended sympathectomized rats did not demonstrate a decrease in the VO2 max values that was observed in saline-injected controls.

  7. Flow patterns generated by vibrations in weightlessness in binary mixture with Soret effect.

    Science.gov (United States)

    Shevtsova, Valentina; Melnikov, Denis; Gaponenko, Yuri; Lyubimova, Tatyana; Mialdun, Aliaksandr; Sechenyh, Vitaliy

    2012-07-01

    Vibrational convection refers to the specific flows that appear when a fluid with density gradient is subjected to external vibration. The density gradient may result from the inhomogeneity of temperature or composition. The study of vibrational impact on fluids has fundamental and applied importance. In weightlessness, vibrational convection is an additional way of transporting heat and matter similar to thermo- and solutocapillary convection. The response of the fluid to external forcing depends on the frequency of vibration. The case of small amplitude and high frequency vibration (when the period is much smaller than the characteristic viscous and heat (mass) diffusion times) is of special interest. In this case, the mean flow can be observed in the system, which describes the non-linear response of the fluid to a periodic excitation. The mean flow is most pronounced in the absence of other external forces (in particular, absence of static gravity). The experiment IVIDIL (Influence of Vibration on Diffusion in Liquids) has been conducted on the ISS during more than 3 months in 2009-2010. In the experimental liquids the density changes due to both the temperature and composition. 55 experimental runs of IVIDIL provided rich variety of valuable information about behavior of the liquid in weightlessness which is released with time, [1-3]. The current results provide experimental and numerical evidence of richness of flow patterns and their classification. References: 1. Shevtsova V., Mialdun A., Melnikov D., Ryzhkov I., Gaponenko Y., Saghir Z., Lyubimova T., Legros J.C., IVIDIL experiment onboard ISS: thermodiffusion in presence of controlled vibrations, Comptes Rendus Mecanique, 2011, 339, 310-317 2. Shevtsova V., Lyubimova T., Saghir Z. , Melnikov D., Gaponenko Y. , Sechenyh V. , Legros J.C. , Mialdun A., IVIDIL: on-board g-jitters and diffusion controlled phenomena; Journal of Physics: Conference Series, 2011, 327, 012031 3. Mazzoni S., Shevtsova V., Mialdun A

  8. Simulated weightlessness and synbiotic diet effects on rat bone mechanical strength

    Science.gov (United States)

    Sarper, Hüseyin; Blanton, Cynthia; DePalma, Jude; Melnykov, Igor V.; Gabaldón, Annette M.

    2014-10-01

    This paper reports results on exposure to simulated weightlessness that leads to a rapid decrease in bone mineral density known as spaceflight osteopenia by evaluating the effectiveness of dietary supplementation with synbiotics to counteract the effects of skeletal unloading. Forty adult male rats were studied under four different conditions in a 2 × 2 factorial design with main effects of diet (synbiotic and control) and weight condition (unloaded and control). Hindlimb unloading was performed at all times for 14 days followed by 14 days of recovery (reambulation). The synbiotic diet contained probiotic strains Lactobacillus acidophilus and Lactococcus lactis lactis and prebiotic fructooligosaccharide. This paper also reports on the development of a desktop three-point bending device to measure the mechanical strength of bones from rats subjected to simulated weightlessness. The importance of quantifying bone resistance to breakage is critical when examining the effectiveness of interventions against osteopenia resulting from skeletal unloading, such as astronauts experience, disuse or disease. Mechanical strength indices provide information beyond measures of bone density and microarchitecture that enhance the overall assessment of a treatment's potency. In this study we used a newly constructed three-point bending device to measure the mechanical strength of femur and tibia bones from hindlimb-unloaded rats fed an experimental synbiotic diet enriched with probiotics and fermentable fiber. Two calculated outputs for each sample were Young's modulus of elasticity and fracture stress. Bone major elements (calcium, magnesium, and phosphorous) were quantified using ICP-MS analysis. Hindlimb unloading was associated with a significant loss of strength in the femur, and with significant reductions in major bone elements. The synbiotic diet did not protect against these unloading effects. Tibia strength and major elements were not reduced by hindlimb unloading, as was

  9. Physiological responses of women to simulated weightlessness: A review of the first female bed-rest study

    Science.gov (United States)

    Sandler, H.; Winter, D. L.

    1978-01-01

    Subjects were exposed to centrifugation, to lower body negative pressure (LBNP), and to exericse stress both before and after bed rest. Areas studied were centrifugation tolerance, fluid electrolyte changes and hematology, tolerance to LBNP, physical working capacity, biochemistries, blood fibrinolytic activity, female metabolic and hormonal responses, circadian alterations, and gynecology. Results were compared with the responses observed in similarly bed-rested male subjects. The bed-rested females showed deconditioning responses similar to those of the males, although with some differences. Results indicate that women are capable of coping with exposure to weightlessness and, moreover, that they may be more sensitive subjects for evaluating countermeasures to weightlessness and developing criteria for assessing applicants for shuttle voyages.

  10. Biological effects of weightlessness and clinostatic conditions registered in cells of root meristem and cap of higher plants

    Science.gov (United States)

    Sytnik, K. M.; Kordyum, E. L.; Belyavskaya, N. A.; Nedukha, E. M.; Tarasenko, V. A.

    Research in cellular reproduction, differentiation and vital activity, i.e. processes underlying the development and functioning of organisms, plants included, is essential for solving fundamental and applied problems of space biology. Detailed anatomical analysis of roots of higher plants grown on board the Salyut 6 orbital research station show that under conditions of weightlessness for defined duration mitosis, cytokinesis and tissue differentiation in plant vegetative organs occur essentially normally. At the same time, certain rearrangements in the structural organization of cellular organelles - mainly the plastid apparatus, mitochondria, Golgi apparatus and nucleus - are established in the root meristem and cap of the experimental plants. This is evidence for considerable changes in cellular metabolism. The structural changes in the subcellular level arising under spaceflight conditions are partially absent in clinostat experiments designed to simulate weightlessness. Various clinostatic conditions have different influences on the cell structural and functional organization than does space flight. It is suggested that alterations of cellular metabolism under weightlessness and clinostatic conditions occur within existing genetic programs.

  11. Fluid shifts and muscle function in humans during acute simulated weightlessness

    Science.gov (United States)

    Hargens, A. R.; Tipton, C. M.; Gollnick, P. D.; Mubarak, S. J.; Tucker, B. J.; Akeson, W. H.

    1983-01-01

    The acute effects of simulated weightlessness on transcapillary fluid balance, tissue fluid shifts, muscle function, and triceps surface reflex time were studied in eight supine human subjects who were placed in a 5 degrees head-down tilt position for 8 hr. Results show a cephalic fluid shift from the legs as indicated by facial edema, nasal congestion, increased urine flow, decreased creatinine excretion, reduced calf girth, and decreased lower leg volume. The interstitial fluid pressure in the tibialis anterior muscle and subcutaneous tissue of the lower leg was found to fall significantly, while other transcapillary pressures (capillary and interstitial fluid colloid osmotic pressures) were relatively unchanged. The total water content of the soleus muscle was unchanged during the head-down tilt. After head-down tilt, isometric strength and isokinetic strength of the plantar flexors were unchanged, while the triceps surae reflex time associated with plantar flexion movement slowed slightly. These results demonstrate a dehydration effect of head-down tilt on muscle and subcutaneous tissue of the lower leg that may affect muscle function.

  12. External Load Affects Ground Reaction Force Parameters Non-uniformly during Running in Weightlessness

    Science.gov (United States)

    DeWitt, John; Schaffner, Grant; Laughlin, Mitzi; Loehr, James; Hagan, R. Donald

    2004-01-01

    Long-term exposure to microgravity induces detrimefits to the musculcskdetal system (Schneider et al., 1995; LeBlanc et al., 2000). Treadmill exercise is used onboard the International Space Station as an exercise countermeasure to musculoskeletal deconditioning due to spaceflight. During locomotive exercise in weightlessness (0G), crewmembers wear a harness attached to an external loading mechanism (EL). The EL pulls the crewmember toward the treadmill, and provides resistive load during the impact and propulsive phases of gait. The resulting forces may be important in stimulating bone maintenance (Turner, 1998). The EL can be applied via a bungee and carabineer clip configuration attached to the harness and can be manipulated to create varying amounts of load levels during exercise. Ground-based research performed using a vertically mounted treadmill found that peak ground reaction forces (GRF) during running at an EL of less than one body weight (BW) are less than those that occur during running in normal gravity (1G) (Davis et al., 1996). However, it is not known how the GRF are affected by the EL in a true OG environment. Locomotion while suspended may result in biomechanics that differ from free running. The purpose of this investigation was to determine how EL affects peak impact force, peak propulsive force, loading rate, and impulse of the GRF during running in 0G. It was hypothesized that increasing EL would result in increases in each GRF parameter.

  13. Visualization Study of Supercritical Fluid Convection and Heat Transfer in Weightlessness by Interferometry: A Brief Review

    Science.gov (United States)

    Deng, Bi-Li; Kanda, Yuki; Chen, Lin; Okajima, Junnosuke; Komiya, Atsuki; Maruyama, Shigenao

    2017-08-01

    Supercritical fluids have become a hot topic in recent years, due to their wide applications in chemical and energy systems. With its sensitive thermal-transport properties in the near-critical region, supercritical/near-critical fluids behaviors, under both microgravity and terrestrial conditions, have become very interesting and challenging topic. This brief review is focused on the visualization experiments of fluid convection and heat transfer related critical phenomena by interferometer. Due to the sensitive property changes of critical fluids, it is very difficult to control and measure the supercritical fluid behaviors. In this review, non-intrusive visualization systems by interferometry are introduced and analyzed for experimental studies of fluids in the near-critical region. For near-critical and supercritical experiments, the temperature/density control and parameter analysis are of critical importance. The analysis of boundary conditions, convection behaviors and energy transfer modes of critical fluids, mainly under weightlessness, are also reviewed with recent opinions toward future development. It is hoped that this review could be helpful for related studies.

  14. Relationships between orientation, movement and posture in weightlessness: Preliminary ethological observations

    Science.gov (United States)

    Tafforin, Carole

    Weightlessness in man induces changes in astronaut orientations and consequently in his patterns of movements and postures. An ethological method has been used to describe the "overall" spontaneous behaviour of astronauts as seen from video recordings made during Space Flights. The work has consisted in analysing the relationships between orientation, movement and posture as an indication of a motor adaptative reorganization in such a situation. The results obtained lead us to consider three different aspects: (1) Orientation references. The astronaut orientates himself with reference to the Space Shuttle's internal structure; the increase of visual activity confirms the choice of the retinal vertical as frame of reference. (2) Motor coordination. The main data reveals a decrease in motor stereotypies by the diversity of motor acts observed and the importance of the link between orientation and posture described as follows: slightly inclined forward position, with legs flexed at about 135°. (3) Cognitive references. There appears to be a new organization of the cognitive image of the body scheme, the missing vestibular information being supplied by peripheral vision instead which could play a role in the astronaut's perception of his own movement.

  15. The Role of GH/IGF-I Axis in Muscle Homeostasis During Weightlessness

    Science.gov (United States)

    Schwartz, Robert J.

    1997-01-01

    Exposure to reduced gravity during space travel profoundly alters the loads placed on bone and muscle. Astronauts suffer significant losses of muscle and bone strength during weightlessness. Exercise as a countermeasure is only partially effective in remedying severe muscle atrophy and bone demineralization. Similar wasting of muscles and bones affects people on Earth during prolonged bed rest or immobilization due to injury. In the absence of weight bearing activity, atrophy occurs primarily in the muscles that act in low power, routine movements and in maintaining posture. Hormonal disfunction could contribute in part to the loss of muscle and bone during spaceflight. Reduced levels of human Growth Hormone (hGH) were found in astronauts during space flight, as well as reduced GH secretory activity was observed from the anterior pituitary in 7-day space flight rats. Growth hormone has been shown to be required for maintenance of muscle mass and bone mineralization, in part by mediating the biosynthesis IGF-I, a small polypeptide growth factor. IGF biosynthesis and secretion plays an important role in potentiating muscle cell differentiation and has been shown to drive the expression of myogenin, a myogenic specific basic helix-loop-helix factor. IGF-I has also been shown to have an important role in potentiating muscle regeneration, repair and adult muscle hypertrophy.

  16. THE MORPHOLOGICAL CHANGES IN MUSCLE SPINDLES AND ALTERATIONS IN CELL ACTIVITY OF THE RATS' RED NUCLEUS AFTER 2 WEEKS' SIMULATED WEIGHTLESSNESS

    Institute of Scientific and Technical Information of China (English)

    Zhu Yongjin; Fan Xiaoli; Wu Sudi; Li Qiang

    2006-01-01

    Objective To study the morphological changes of soleus muscle spindle and electrical activity of neurons in Red Nucleus(RN) of the rat after 2 weeks' simulated weightlessness, and to reveal the interaction between proprioceptive inputs of muscle spindles and reciprocal alterations in RN under simulated weightlessness. Methods Twenty female rats were exposed to weightlessness simulated by tail-suspension for 14 days (SW-14d). Body weight(200-220g) matched female rats were control group(Con). The morphological changes in isolated muscle spindle of soleus muscle, the discharges of red nucleus neurons were observed after 14d tail-suspensions by silver staining and extracellular recording respectively. Results Compared with control group ,the nerve ending of muscle spindle in SW-14d was distorted, degenerated and dissolved; the diameters of intrafusal fibers and capsule in equatorial region of soleus muscle spindles were diminished(P<0.05). The spontaneous cell activity and discharge of RN neurons (spikes/s) induced by afferent firing from muscle spindles after injection of succinylcholine were reduced after 2 weeks' simulated weightlessness respectively (18.44±5.96 vs. 10.19±6.88, 32.50±8.08 vs. 16.86±5.97, P<0.01). Conclusion The degeneration of muscle spindle induced by simulated weightlessness may be one of the causes that led to alterations in discharges of RN.

  17. The different effects of high intensity interval training and moderate intensity interval training for weightlessness countermeasures

    Science.gov (United States)

    Wang, Lin-Jie; Cheng, Tan; Zhi-Li, Li; Hui-juan, Wang; Wen-juan, Chen; Jianfeng, Zhang; Desheng, Wang; Dongbin, Niu; Qi, Zhao; Chengjia, Yang; Yanqing, Wang

    High intensity interval training (HIIT) has been demonstrated to improve performance in a relatively short training period. But the difference between high intensity interval training and moderate intensity interval training (MIIT) in simulated weightlessness still has not been well studied. This study sought to characterize the difference between 6 weeks high intensity interval training and moderate intensity interval training under reduced weight (RW) gait training device and zero-gravity locomotion system (ZLS). Twenty-three subjects (14M/4F, 32.5±4.5 years) volunteered to participate. They were divided into three groups, that were MITT (alternating 2 min at 40% VO _{2} peak and 2 min at 60% VO _{2} peak for 30min, five days per week) RW group (n=8), HITT (alternating 2 min at 40% VO _{2} peak and 2 min at 90% VO _{2} peak for 30min, three days per week) RW group (n=8) and HITT ZLS group (n=7). The Z-axis load used in RW group was 80% body weight (BW) and in ZLS was 100% BW. Cardiopulmonary function was measured before, after 4-week training and after 6-week training. Isokinetic knee extension-flexion test at 60(°) deg/s and 180(°) deg/s were performed before and after the 6-week training, and isometric knee extension-flexion test at 180(°) deg/s was also examined at the same time. It was found that the VO _{2} peaks, metabolic equivalent (MET), Speedmax and respiratory exchange ratio (RER) were significantly increased after 4 and 6-week training in all three groups and no significant group difference were detected. The peak torque at 60(°) deg/s for right knee flexion were significantly increased after 6 week-training in all three groups, and only in HITT RW group the total power at 60(°) deg/s for right knee flexion enhanced. The total power and average power at 60(°) deg/s for right knee extension decreased significantly after 6-week training in all three groups. The peak torque at 60(°) deg/s for right knee extension in MIIT RW group was

  18. Expressions of integrin subunits in osteoblasts during weightlessness simulation using clionstat

    Science.gov (United States)

    Zhang, S.; Wang, B.; Zhao, D.; Nie, J.; Li, Y.

    Space flight experiments and studies carried out in altered gravity environments have revealed that exposure to altered gravity conditions results in (mal)adaptation of cellular function. In the present study, we used a clinostat to generate a vector-averaged gravity to simulate weightlessness environment. We then observed the responses of rat calvarial osteoblasts subsequent to rotation at 30 revolutions per minute (rpm) for 72 h. We found that the gene expressions of three integrin subunits started to change from 24 h of rotation in clinostat but not in stationary cultures. The decreased percent changes of integrin a5 mRNA at 24, 48 and 72 h were 11.3 +/- 2.6%, 18.7 +/- 4.2% and 9.8 +/ - 2.1%, respectively. The same trend was saw in the expression of integrin av mRNA as 23.0 +/- 4.7%, 12.3 +/- 1.6% and 16.7 +/- 3.2%, respectively. Moreover, the expressions of integrin ß1 mRNA in different periods were also declined with the percent changes of 15.3 +/- 1.3%, 11.4 +/- 1.2% and 26.4 +/- 5.5%, respectively. All cells contain membrane-anchored attachment proteins able to recognize specific chemical motifs in the extracellular macromolecules forming the supporting scaffold, made of various types of collagen, adhesive glycoproteins, elastin, proteoglycans, etc. These cell-matrix interactions are mainly mediated by receptors of the integrins family, heterodimeric molecules made of an extracellular domain connected through a transmembrane sequence to an intracytoplasmic tail. Our results suggest that vector-averaged gravity causes alterations of signal transduction and integrin-mediated cell adhesion in osteoblasts by altering the gene expressions of several crucial integrin subunits. These alterations might contribute to the pathogenesis of osteoporotic bone loss as observed in actual space flights.

  19. Changes in the loco-regional cerebral blood flow (r.C.B.F.) during a simulation of weightlessness

    Science.gov (United States)

    Guell, A.; Dupui, Ph.; Barrere, M.; Fanjaud, G.; Bes, A.; Kotowskaia, A.

    Experiments of prolonged bedrest in antiorthostatic position are conducted in order to simulate cardio-circulatory modifications observed in weightlessness. Until now, no studies of r.C.B.F. have been effected in these conditions. Six young, healthy volunteers (average age 23.8) were placed in strict bedrest and in antiorthostatic position -4° for 7 days. The r.C.B.F. measurements were studied by 133Xe inhalation method using a 32 detectors system. Studies were made first in basal conditions, then between the 6th and 12th hr, and finally between the 72nd and the 78th hr after the beginning of the experiment. Three of the subjects received 0.450 mg of Clonidine daily during the experiment. In the subjects having taken no Clonidine, we observed a constant increase in r.C.B.F. (12, 17 and 16% respectively) in the first 12 hr; at the 72nd hour, all values had returned to basal state. This findings agrees with the well known notion of a rapid correction of hemodynamic disturbances observed in the first days of weightlessness. In the subjects treated with Clonidine, the increase of r.C.B.F. did not occur. Several mechanicsms of action are possible; the Clonidine affecting either the heart by inhibiting volemic atrial receptors, or the brain by direct vasoconstriction.

  20. Influences of traditional Chinese medicine intervention on the bone growth and metabolism of rats with simulated weightlessness

    Institute of Scientific and Technical Information of China (English)

    Jun Zhu

    2013-01-01

    Objective:To probe into the influences ofChinese herbal compound on the growth and metabolism of weight-bearing bones of tail-suspended rats.Methods:Twenty-four maleSD rats were randomly divided into blank control group(eight), tail-suspended control group(eight) and Chinese medicine treatment group(eight) according to their weights.No treatment was done for the blank control group.Double distilled water lavage was performed daily for the tail-suspended control group.On the basis of the tail-suspended rat model, the rats were givenChinese herbal compound lavage every day inChinese medicine treatment group.This compound includes mulberry,Poria cocos and barbary wolfberry,etc.The test cycle was four weeks.The rats were killed after the experiment.The right femoral bone was taken out for the physical measurements, and the left femoral bone was for the three-point bending test.The influences ofChinese herbal compound on femoral bone growth and biomechanical properties of simulated weightlessness rats were observed.Results:(1)After simulated weightlessness(tail-suspension), compared with the blank control group, all the physiological indexes of rat femoral bone decreased in tail-suspended group andChinese medicine treatment group(P<0.05).The strength and rigidity of rat femoral bone decreased in tail-suspended group(P<0.01).The maximum load and rigidity coefficient also decreased with the increasing toughness coefficient in the control group(P<0.01). (2)After the countermeasure ofChinese herbal compound, each biomechanical indexes showed the tendency of increasing inChinese medicine treatment group, and theses indexes were close to those of the blank control group(P<0.05), which indicated that the bone loss caused by simulated weightlessness was improved.Conclusions:Chinese herbal compound for tonifying kidney could effectively prevent the bone loss and have some enhancements on the bone biomechanical properties.

  1. Influence of standing surface waves on thermocapillary convection stability and crystal growth in weightlessness

    Science.gov (United States)

    Feonychev, A. I.

    ), amplitude of oscillations for all parameters, including radial macrosegregation, can be reduced by the factor 5 under optimal choosing of vibration parameters. Thus, the study of surface standing waves shown that it is a possibility to reduce both macrosegregation and microsegregation of dopant under crystal growth by the floating zone method in microgravity. The use of magnetic field for elimination of residual oscillations generated by vibration is discussed. It was shown that inertia-capillary waves could be used for measurement of total vibration existing on ISS. The program of experiments for study of surface standing and crystal growth by the floating zone method aboard ISS is suggested. The experiment with inertia-capillary waves had been included in program of scientific investigation on Russian segment of ISS in 1998 but not realized until now. References 1. Feonychev A.I., Kalachinskaya I.S. and Pokhilko V.I. NASA Conference Publication 3338. 1996, pp. 493-498. 2. Feonychev A.I. Inertia-capillary surface waves and their effect on crystal growth in weightlessness (in press, in Russia).

  2. Effects of simulated weightlessness on the kinase activity of MEK1 induced by bone morphogenetic protein-2 in rat osteosarcoma cells

    Science.gov (United States)

    Zhang, S.; Wang, B.; Cao, X. S.; Yang, Z.

    Objective The mRNA expression of alpha 1 chain of type I collagen COL-I alpha 1 in rat osteosarcoma ROS17 2 8 cells induced by bone morphogenetic protein-2 BMP-2 was reduced under simulated microgravity The protein kinase MEK1 of MAPK signal pathway plays an important role in the expression of COL-I alpha 1 mRNA The purpose of this study is to investigate the effects of simulated weightlessness on the activity of MEK1 induced by BMP-2 in ROS17 2 8 cells Methods ROS17 2 8 cells were cultured in 1G control and rotating clinostat simulated weightlessness for 24 h 48 h and 72 h BMP-2 500 ng ml was added into the medium 1 h before the culture ended There was a control group in which ROS17 2 8 cells were cultured in 1G condition without BMP-2 Then the total protein of cells was extracted and the expression of phosphated-ERK1 2 p-ERK1 2 protein was detected by means of Western Blotting to show the kinase activity of MEK1 Results There were no significant differences in the expression of total ERK1 2 among all groups The expression of p-ERK1 2 was unconspicuous in the control group without BMP-2 but increased significantly when BMP-2 was added P 0 01 The level of p-ERK1 2 in simulated weightlessness group was much more lower than that in 1G group in every time point P 0 01 The expression of p-ERK1 2 gradually decreased along with the time of weightlessness simulation P 0 01 Conclusions The kinase activity of MEK1 induced by BMP-2 in rat osteosarcoma cells was reduced under simulated weightlessness

  3. M.I.T./Canadian vestibular experiments on the Spacelab-1 mission: 3. Effects of prolonged weightlessness on a human otolith-spinal reflex

    Science.gov (United States)

    Watt, D. G.; Money, K. E.; Tomi, L. M.

    1986-01-01

    Reflex responses that depend on human otolith organ sensitivity were measured before, during and after a 10 day space flight. Otolith-spinal reflexes were elicited by means of sudden, unexpected falls. In weightlessness, "falls" were achieved using elastic cords running from a torso harness to the floor. Electromyographic (EMG) activity was recorded from gastrocnemius-soleus. The EMG response occurring in the first 100-120 ms of a fall, considered to be predominantly otolith-spinal in origin, decreased in amplitude immediately upon entering weightlessness, and continued to decline throughout the flight, especially during the first two mission days. The response returned to normal before the first post-flight testing session. The results suggest that information coming from the otolith organs is gradually ignored by the nervous system during prolonged space flight, although the possibility that otolith-spinal reflexes are decreased independent of other otolith output pathways cannot be ruled out.

  4. M.I.T./Canadian vestibular experiments on the Spacelab-1 mission. III - Effects of prolonged weightlessness on a human otolith-spinal reflex

    Science.gov (United States)

    Watt, D. G. D.; Money, K. E.; Tomi, L. M.

    1986-01-01

    Reflex responses that depend on human otolith organ sensitivity were measured before, during and after a 10 day space flight. Otolith-spinal reflexes were elicited by means of sudden, unexpected falls. In weightlessness, 'falls' were achieved using elastic cords running from a torso harness to the floor. Electromyographic (EMG) activity was recorded from gastrocnemius-soleus. The EMG response occurring in the first 100-120 ms of a fall, considered to be predominantly otolith-spinal in origin, decreased in amplitude immediately upon entering weightlessness, and continued to decline throughout the flight, especially during the first two mission days. The response returned to normal before the first post-flight testing session. The results suggest that information coming from the otolith organs is gradually ignored by the nervous system during prolonged space flight, although the possibility that otolith-spinal reflexes are decreased independent of other otolith output pathways cannot by ruled out.

  5. Effect of simulated weightlessness on the expression of Cbfα1 induced by fluid shear stress in MG-63 osteosarcoma cells.

    Science.gov (United States)

    Yang, Z.; Zhang, S.; Wang, B.; Sun, X. Q.

    Objective The role of mechanical load in the functional regulation of osteoblasts becomes an emphasis in osseous biomechanical researches recently This study was aim to explore the effect of flow shear stress on the expression of Cbf alpha 1 in human osteosarcoma cells and to survey its functional alteration in simulated weightlessness Method After cultured for 72 h in two different gravitational environments i e 1G terrestrial gravitational condition and simulated weightlessness condition human osteosarcoma cells MG-63 were treated with 0 5 Pa or 1 5 Pa fluid shear stress FSS in a flow chamber for 15 30 60 min respectively The total RNA in cells was isolated Transcription PCR analysis was made to examine the gene expression of Cbf alpha 1 And the total protein of cells was extracted and the expression of Cbf alpha 1 protein was detected by means of Western Blotting Results MG-63 cultured in 1G condition reacted to FSS treatment with an enhanced expression of Cbf alpha 1 Compared with no FSS control group Cbf alpha 1 mRNA and protein expression increased significantly at 30 and 60 min with the treatment of FSS P 0 01 And there was remarkable difference on the Cbf alpha 1 mRNA and protein expression between the treatments of 0 5 Pa and 1 5 Pa FSS at 30 min or 60 min P 0 01 As to the osteoblasts cultured in simulated weightlessness by using clinostat the expression of Cbf alpha 1 was significantly different between 1G and simulated weightlessness conditions at each test time P 0 05 Compared with no FSS

  6. Skylab experiments. Volume 3: Materials science. [Skylab experiments on metallurgy, crystal growth, semiconductors, and combustion physics in weightless environment for high school level education

    Science.gov (United States)

    1973-01-01

    The materials science and technology investigation conducted on the Skylab vehicle are discussed. The thirteen experiments that support these investigations have been planned to evaluate the effect of a weightless environment on melting and resolidification of a variety of metals and semiconductor crystals, and on combustion of solid flammable materials. A glossary of terms which define the space activities and a bibliography of related data are presented.

  7. Anesthesia and critical-care delivery in weightlessness: A challenge for research in parabolic flight analogue space surgery studies

    Science.gov (United States)

    Ball, Chad G.; Keaney, Marilyn A.; Chun, Rosaleen; Groleau, Michelle; Tyssen, Michelle; Keyte, Jennifer; Broderick, Timothy J.; Kirkpatrick, Andrew W.

    2010-03-01

    BackgroundMultiple nations are actively pursuing manned exploration of space beyond low-earth orbit. The responsibility to improve surgical care for spaceflight is substantial. Although the use of parabolic flight as a terrestrial analogue to study surgery in weightlessness (0 g) is well described, minimal data is available to guide the appropriate delivery of anesthesia. After studying anesthetized pigs in a 0 g parabolic flight environment, our group developed a comprehensive protocol describing prolonged anesthesia in a parabolic flight analogue space surgery study (PFASSS). Novel challenges included a physically remote vivarium, prolonged (>10 h) anesthetic requirements, and the provision of veterinary operating room/intensive care unit (ICU) equivalency on-board an aircraft with physical dimensions of ethical approval, multiple ground laboratory sessions were conducted with combinations of anesthetic, pre-medication, and induction protocols on Yorkshire-cross specific pathogen-free (SPF) pigs. Several constant rate infusion (CRI) intravenous anesthetic combinations were tested. In each regimen, opioids were administered to ensure analgesia. Ventilation was supported mechanically with blended gradients of oxygen. The best performing terrestrial 1 g regime was flight tested in parabolic flight for its effectiveness in sustaining optimal and prolonged anesthesia, analgesia, and maintaining hemodynamic stability. Each flight day, a fully anesthetized, ventilated, and surgically instrumented pig was transported to the Flight Research Laboratory (FRL) in a temperature-controlled animal ambulance. A modular on-board surgical/ICU suite with appropriate anesthesia/ICU and surgical support capabilities was employed. ResultsThe mean duration of anesthesia (per flight day) was 10.28 h over four consecutive days. A barbiturate and ketamine-based CRI anesthetic regimen supplemented with narcotic analgesia by bolus administration offered the greatest prolonged hemodynamic

  8. The effect of the configuration and the interior design of a virtual weightless space station on human spatial orientation.

    Science.gov (United States)

    Aoki, Hirofumi; Ohno, Ryuzo; Yamaguchi, Takao

    2005-01-01

    In a virtual weightless environment, subjects' orientation skills were studied to examine what kind of cognitive errors people make when they moved through the interior space of virtual space stations and what kind of visual information effectively decreases those errors. Subjects wearing a head-mounted display moved from one end to the other end in space station-like routes constructed of rectangular and cubical modules, and did Pointing and Modeling tasks. In Experiment 1, configurations of the routes were changed with such variables as the number of bends, the number of embedding planes, and the number of planes with respect to the body posture. The results indicated that spatial orientation ability was relevant to the variables and that orientational errors were explained by two causes. One of these was that the place, the direction, and the sequence of turns were incorrect. The other was that subjects did not recognize the rotation of the frame of reference, especially when they turned in pitch direction rather than in yaw. In Experiment 2, the effect of the interior design was examined by testing three design settings. Wall colors that showed the allocentric frame of reference and the different interior design of vertical and horizontal modules were effective; however, there was a limit to the effectiveness in complicated configurations. c2005 Published by Elsevier Ltd.

  9. Effects of electrostimulation and administration of succinylcholine on the expression of Fos protein in mesencephalic periaqueductal gray matter of rats after simulated weightlessness

    Institute of Scientific and Technical Information of China (English)

    Yongjin Zhu; Sudi Wu; Xiaoli Fan; Xinai Song; Linping Xu

    2006-01-01

    BACKGROUND: Expression of Fos in neurons of periaqueductal gray (PAG) is used to reflect the excitability.However, changes of expression of Fos in neurons of PAG are caused by injured electrostimulation after simulated weightlessness, and the relationship between pretreatment and injection of succinylcholine has not been determined yet.OBJECTIVE: To investigate the changes of expression of Fos in PAG induced by injured electrostimulation,pretreatment and injection of succinylcholine at 2 weeks after simulated weightlessness.DESIGN: Observational and controlled animal study.SETTING: Department of Physiology, Medical School, Xi'an Jiaotong University; Key Laboratory of Environment and Genes Related to Diseases, Ministry of Education.MATERIALS: A total of 24 adult female SD rats, of clean grade and weighing 180-220 g, were selected in this study.METHODS: The experiment was completed in the Experimental Animal Center of Xi'an Jiaotong University.① All rats were randomly divided into 2 groups according to body mass: simulated weightlessness group and control group with 12 in each group. And then, each group was also divided into 3 subgroups: electrostimulation group, succinylcholine-pretreatment group and succinylcholine-injection group with 4 in each subgroup. ② The model of weightlessness was simulated by tail-suspended female rats, which were described and modified by Cheng Jie. Rats in normal control group were given the same interventions as simulated weightlessness group except for tail-suspended. ③ Experimental method: The rats in electrostimulation group were given nociceptive stimulus by a pair of subcutaneous electrodes inserted into 1 and 5 claw of left hindlimb. The stimulus (current: 10 mA; duration: 1 ms; interval: 1 s) lasted for 30 minutes. The rats in succinylcholine-pretreatment group received stimulus after intravenous administration of succinylcholine, rats in succinylcholine-injection group were not given stimulus, just received

  10. Weightlessness causes lower limb muscle atrophy%失重状态造成肌萎缩的研究与进展

    Institute of Scientific and Technical Information of China (English)

    韩忠宇; 贾懿劼; 田京

    2013-01-01

      背景:失重是导致宇航员下肢肌萎缩的重要原因之一,严重危害宇航员身体健康。目的:探讨失重状态造成肌萎缩的发生机制。方法:由第一作者分别应用计算机检索 PubMed 英文数据库和中国期刊全文数据库中1997年5月至2013年3月的文献。在标题、和关键词中以“weightless,weightlessness,muscle,atrophy,space,失重,骨骼肌,萎缩,太空”为检索词进行检索。选择文章内容与失重状态造成肌萎缩研究机制相关者,同一领域则选择最新研究进展者。结果与讨论:初选得到文献409篇,根据纳入标准选择47篇文献进行综述。失重状态造成肌萎缩的发生机制是目前宇航医学的研究热点。目前造成失重性肌萎缩主要原因主要包括外周感觉神经所获取信息传导减少导致肌梭神经营养因子合成减少、肌细胞超微结构破坏:线粒体肌原纤维大幅下降、肌钙合成蛋白质减少、肌细胞内钙含量减少,下肢抗重力肌群血流量减少等多方面。%BACKGROUND: Weightlessness is one of the important reasons to cause lower limb muscle atrophy of the astronauts, which is serious harm to the health of astronauts. OBJECTIVE: To explore the progress of weightlessness that cause lower limb muscle atrophy. METHODS: A computer-based online search of PubMed database and CNKI database was performed to search related articles between May 1981 and March 2013 with the key words of “weightless, weightlessness, muscle, atrophy, space” in English and Chinese, respectively. Literatures related to progress of weightlessness that cause lower limb muscle atrophy were selected; in the same field, the literatures published lately in authoritative journals were preferred. RESULTS AND CONCLUSION: A total of 409 literatures were primarily selected, and 47 documents were involved for summary according to the inclusion criteria. The progress of weightlessness that

  11. Intake of Fish and Omega-3 (n-3) Fatty Acids: Effect on Humans During Actual and Simulated Weightlessness

    Science.gov (United States)

    Smith, S. M.; Pierson, D. L.; Mehta, S. K.; Zwart, S. R.

    2011-01-01

    Space flight has many negative effects on human physiology, including bone and muscle loss. Bone and muscle are two systems that are positively affected by dietary intake of fish and n-3 fatty acids. The mechanism is likely to be related to inhibition by n-3 fatty acids of inflammatory cytokines (such as TNF) and thus inhibition of downstream NF-kB activation. We have documented this effect in a 3-dimensional cell culture model, where NF-kB activation in osteoclasts was inhibited by eicosapentaenoic acid, an n-3 fatty acid. We have also indentified that NF-kB activation in peripheral blood mononuclear cells of Space Shuttle crews. We found that after Shuttle flights of 2 wk, expression of the protein p65 (evidence of NF-kB activation) was increased at landing (P less than 0.001). When evaluating the effects of n-3 fatty acid intake on bone breakdown after 60 d of bed rest (a weightlessness analog). We found that after 60 d of bed rest, greater intake of n-3 fatty acids was associated with less N-telopeptide excretion (Pearson r = -0.62, P less than 0.05). We also evaluated the relationship of fish intake and bone loss in astronauts after 4 to 6 mo missions on the International Space Station. Higher consumption of fish during flight was associated with higher bone mineral density (Pearson r = 0.46, P less than 0.05). Together, these findings provide evidence of the cellular mechanism by which n-3 fatty acids can inhibit bone loss, and preliminary human evidence of the potential for n-3 fatty acids to counteract bone loss associated with space flight. This study was supported by the NASA Human Research Program.

  12. Intake of Fish and Omega-3 (N-3) Fatty Acid: Effect on Humans during Actual and Simulated Weightlessness

    Science.gov (United States)

    Smith, Scott M.; Mehta, Satish K.; Pierson, Duane L.; Zwart, Sara R.

    2009-01-01

    Space flight has many negative effects on human physiology, including bone and muscle loss. These are some of the systems on which intakes of fish and n-3 fatty acids have positive effects. These effects are likely to occur through inhibition of inflammatory cytokines (such as TNFalpha) and thus inhibition of downstream NF-KB activation. We documented this effect in a 3D cell culture model, where NF-KB activation in osteoclasts was inhibited by eicosapentaenoic acid, an n-3 fatty acid. We have extended these studies and report here (a) NF-KB expression in peripheral blood mononuclear cells of Space Shuttle crews on 2-wk missions, (b) the effects of n-3 fatty acid intake after 60 d of bed rest (a weightlessness analog), and (c) the effects of fish intake in astronauts after 4 to 6 mo on the International Space Station. After Shuttle flights of 2 wk, NFKB p65 expression at landing was increased (P less than 0.001). After 60 d of bed rest, higher intake of n-3 fatty acids was associated with less N-telopeptide excretion (Pearson r = -0.62, P less than 0.05). Higher consumption of fish during flight was associated with higher bone mineral density (Pearson r = -0.46, P less than 0.05). Together with our earlier findings, these data provide mechanistic cellular and preliminary human evidence of the potential for n-3 fatty acids to counteract bone loss associated with spaceflight. This study was supported by the NASA Human Research Program.

  13. The Interaction of the Space Shuttle Launch and Entry Suits and Sustained Weightless on Astronaut Egress Locomotion

    Science.gov (United States)

    Greenisen, M. C.; Bishop, P. A.; Sothmann, M.

    2008-01-01

    The purpose of this study was to determine the consequences of extended periods of weightlessness during space missions on astronauts f ability to perform a simulated contingency egress while wearing either of the Launch and Entry suits immediately after space flight. In our previous lab-based study of simulated contingency egress, we found only 4 of 12 non-astronauts wearing the Launch and Entry Suit (LES) successfully completed the simulated egress. However, 4 of 4 of the previous failures (when tested wearing the LES), were then successful in completing the test wearing the Advanced Crew Escape Suit (ACES). Therefore, this study tested 21 Astronaut Volunteers wearing either the LES or ACES while performing a simulated egress on a treadmill (TM) onboard the Crew Transportation Vehicle immediately after space flight at either the Kennedy Space Center or Edwards AFB. Astronauts walked for 400 meters at 1.6m/sec with g-suit inflation level set to preflight testing levels, visor down, breathing from the suit emergency O2 supply. Metabolic, heartrate, and perceived exertion data were collected during these post-flight tests. Exactly the same preflight simulated egress tests on a TM were performed in the lab at NASA/JSC by each crewmember at L-60. Preflight testing found 2 of the 21 crewmembers were unable to complete the simulated contingency egress. Postflight, 9 crew (8 ACES, 1 LES) completed the simulated contingency egress of 400 meters at 1.6m/sec. and 12 failed to meet that standard (7 ACES, 5 LES). Preflight physiological response tests failed to identify crew capable of performing the egress vs. those who failed. However, 18 of the 21 crew did make at least 2.67 minutes into the postflight egress testing. At that point in time, heartrate was higher (P <=.20) for the failures compared to the finishers. These findings indicate that NASA fs switch to the ACES for space flight crews should be expedited.

  14. Recent progress of weightlessness impact on the eye%失重状态对眼部影响的研究进展

    Institute of Scientific and Technical Information of China (English)

    杨振菲; 朱思泉

    2015-01-01

    The impact of weightlessness on the eye becomes more and more important with the increase of human space exploration.There is significant elevation in cephalad fluid and ophthalmic vein when individuals are in the state of weightlessness.In this paper,we review adverse effects in weightlessness station,including:retina damage (disc edema,choroidal folds,cotton wool spots,nerve fiber layer thickening),visual function decrease (decreased near vision,decreased ability of acquire and fixate on the target),and intraocular pressure increase.%随着人类太空探索的增加,失重状态下的人体改变成为许多科学家研究的热点.失重状态下,头面部血流分配会增加,随之也会造成眼部供血状态的改变,这种改变对眼部产生一系列的病理生理变化.本文综述了失重状态对眼部的主要影响,包括眼底病变(视乳头水肿、脉络膜皱褶、棉絮斑、神经纤维层增厚),视功能下降(近视力下降、固视和追随物体能力下降、视网膜和视路功能受损)及眼压升高.

  15. Comparative study on measured variables and sensitivity to bone microstructural changes induced by weightlessness between in vivo and ex vivo micro-CT scans.

    Science.gov (United States)

    Sun, Lian Wen; Wang, Chao; Pu, Fang; Li, De Yu; Niu, Hai Jun; Fan, Yu Bo

    2011-01-01

    Depending on the experimental design, micro-CT can be used to examine bones either in vivo or ex vivo (excised fresh or formalin-fixed). In this study we investigated if differences exist in the variables measured by micro-CT between in vivo and ex vivo scans and which kind of scan is more sensitive to the changes of bone microstructure induced by simulated weightlessness. Rat tail suspension was used to simulate the weightless condition. The same bone from either normal or tail-suspended rats was scanned by micro-CT both in vivo and ex vivo (fresh and fixed by formalin). Then, bone mineral density (BMD) and microstructural characteristics were analyzed. The results showed that no significant differences existed in the microstructural parameters of trabecular bone among in vivo, fresh, and formalin-fixed bone scans from both femurs and tibias, although BMD exhibited differences. On the other hand, most parameters of the tail-suspended rats measured by micro-CT deteriorated compared with controls. Ex vivo scanning appeared to be more sensitive to bone microstructural changes induced by tail suspension than in vivo scanning. In general, the results indicate that values obtained in vivo and ex vivo (fresh and fixed) are comparable, thus allowing for meaningful comparison of experimental results from different studies irrespective of the type of scans. In addition, this study suggests that it is better to use ex vivo scanning when evaluating bone microstructure under weightlessness. However, researchers can select any type of scan depending upon the objective and the demands of the experiment.

  16. A comparison of autonomic responses in humans induced by two simulation models of weightlessness: lower body positive pressure and 6 degrees head-down tilt.

    Science.gov (United States)

    Fu, Q; Sugiyama, Y; Kamiya, A; Mano, T

    2000-04-12

    Six-degree head-down tilt (HDT) is well accepted as an effective weightlessness model in humans. However, some researchers utilized lower body positive pressure (LBPP) to simulate the cardiovascular and renal effects of a decreased gravitational stress. In order to determine whether LBPP was a suitable model for simulated weightlessness, we compared the differences between these two methods. Ten healthy males, aged 21-41 years, were subjected to graded LBPP at 10, 20 and 30 mmHg, as well as 6 degrees HDT. Muscle sympathetic nerve activity (MSNA) was microneurographically recorded from the tibial nerve along with cardiovascular variables. We found that MSNA decreased by 27% to a similar extent both at low levels of LBPP (10 and 20 mmHg) and HDT. However, at a high level of LBPP (30 mmHg), MSNA tended to increase. Mean arterial pressure was elevated significantly by 11% (10 mmHg) at 30 mmHg LBPP, but remained unchanged at low levels of LBPP and HDT. Heart rate did not change during the entire LBPP and HDT procedures. Total peripheral resistance markedly increased by 36% at 30 mmHg LBPP, but decreased by 9% at HDT. Both stroke volume and cardiac output tended to decrease at 30 mmHg LBPP, but increased at HDT. These results suggest that although both LBPP and HDT induce fluid shifts from the lower body toward the thoracic compartment, autonomic responses are different, especially at LBPP greater than 20 mmHg. We note that high levels of LBPP (>20 mmHg) activate not only cardiopulmonary and arterial baroreflexes, but also intramuscular mechanoreflexes, while 6 degrees HDT only activates cardiopulmonary baroreflexes. We conclude that LBPP is not a suitable model for simulated weightlessness in humans.

  17. [Structural and functional organization of the vestibular apparatus in rats maintained under weightless conditions for 19.5 days aboard the satellite "Cosmos-782"].

    Science.gov (United States)

    Vinnikov, Ia A; Gazenko, O G; Titova, L K; Bronshteĭn, A A; Govardovskiĭ, V I

    1978-01-01

    Vestibular apparatus was investigated in rats subjected to weightlessness for 19.5 days in the satelite "Cosmos-782" and experienced acceleration on launching and landing. Some structural and functional changes were noted. They were seen in otolith clinging to the utricular receptor surface and in the peripheral arrangement of the nucleolus in the nuclei of the receptor cells. It is also possible that increased edema of the vestibular tissue resulted in destruction of some receptor cells, and within the otolith--changes in the form and structure of otoconia. In the horizontal crista the cupula was separated.

  18. THE MORPHOLOGICAL CHANGES IN MUSCLE SPINDLES AND ALTERATIONS IN CELL ACTIVITY OF THE RATS RED NUCLEUS AFTER 2 WEEKS SIMULATED WEIGHTLESSNESS

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The extensive negative effects induced by zerogravity or microgravity where offer special environ-ment are har mful for cos monauts[1-3].The real spaceenvironment has many characteristics,including mi-crogravity,electromagnetic fields,and radiation,which may have an effect on the function and mor-phology of the CNS[4],but the changes in CNSin-duced by si mulated weightlessness on the groundcaused the corresponding adaptive changes of cere-bral circulation,which made alterations in sensoryperception,and the ...

  19. Structural and Functional Organization of the Vestibular Apparatus in Rats Subjected to Weightlessness for 19.5 Days Aboard the Kosmos-782 Satellite

    Science.gov (United States)

    Vinnikov, Y. A.; Gazenko, O. G.; Titova, L. K.; Bronshteyn, A. A.; Govardovskiy, V. I.; Pevzner, R. A.; Gribakin, G. G.; Aronova, M. Z.; Kharkeyevich, T. A.; Tsirulis, T. P.

    1978-01-01

    The vestibular apparatus was investigated in rats subjected to weightlessness for 19.5 days. The vestibular apparatus was removed and its sections were fixed in a glutaraldehyde solution for investigation by light and electron microscopes. Structural and functional charges were noted in the otolith portions of the ear, with the otolith particles clinging to the utricular receptor surface and with the peripheral arrangement of the nucleolus in the nuclei of the receptor cells. It is possible that increased edema of the vestibular tissue resulted in the destruction of some receptor cells and in changes in the form and structure of the otolith. In the horizontal crista, the capula was separated.

  20. Separation of gaseous hydrogen from a water-hydrogen mixture in a fuel cell power system operating in a weightless environment

    Science.gov (United States)

    Romanowski, William E. (Inventor); Suljak, George T. (Inventor)

    1989-01-01

    A fuel cell power system for use in a weightless environment, such as in space, includes a device for removing water from a water-hydrogen mixture condensed from the exhaust from the fuel cell power section of the system. Water is removed from the mixture in a centrifugal separator, and is fed into a holding, pressure operated water discharge valve via a Pitot tube. Entrained nondissolved hydrogen is removed from the Pitot tube by a bleed orifice in the Pitot tube before the water reaches the water discharge valve. Water discharged from the valve thus has a substantially reduced hydrogen content.

  1. Six-Degree Head-Down Tilt Bed Rest: Forty Years of Development as a Physiological Analog for Weightlessness

    Science.gov (United States)

    Smith, Jeffrey D.; Cromwell, Ronita L.; Kundrot, Craig E.; Charles, John B.

    2011-01-01

    Early on, bed rest was recognized as a method for inducing many of the physiological changes experienced by spaceflight. Head-down tilt (HDT) bed rest was first introduced as an analog for spaceflight by a Soviet team led by Genin and Kakurin. Their study was performed in 1970 (at -4 degrees) and lasted for 30 days; results were reported in the Russian Journal of Space Biology (Kosmicheskaya Biol. 1972; 6(4): 26-28 & 45-109). The goal was to test physiological countermeasures for cosmonauts who would soon begin month-long missions to the Salyut space station. HDT was chosen to produce a similar sensation of blood flow to the head reported by Soyuz cosmonauts. Over the next decade, other tilt angles were studied and comparisons with spaceflight were made, showing that HDT greater than 4 degrees was superior to horizontal bed rest for modeling acute physiological changes observed in space; but, at higher angles, subjects experienced greater discomfort without clearly improving the physiological comparison to spaceflight. A joint study performed by US and Soviet investigators, in 1979, set the goal of standardization of baseline conditions and chose 6-degrees HDT. This effectively established 6-degree HDT bed rest as the internationally-preferred analog for weightlessness and, since 1990, nearly all further studies have been conducted at 6-degrees HDT. A thorough literature review (1970-2010) revealed 534 primary scientific journal articles which reported results from using HDT as a physiological analog for spaceflight. These studies have ranged from as little as 10 minutes to the longest duration of 370 days. Long-term studies lasting four weeks or more have resulted in over 170 primary research articles. Today, the 6-degree HDT model provides a consistent, thoroughly-tested, ground-based analog for spaceflight and allows the proper scientific controls for rigorous testing of physiological countermeasures; however, all models have their strengths and limits. The 6

  2. Weightless Materials Science

    Science.gov (United States)

    Curtis, Jeremy

    2012-01-01

    Gravity affects everything we do. Only in very recent years have we been able to carry out experiments in orbit around the Earth and see for the first time how things behave in its absence. This has allowed us to understand fundamental processes better and to design new materials using this knowledge. (Contains 6 figures.)

  3. Quantum weightless neuron dynamics

    OpenAIRE

    PAULA NETO, Fernando Maciano de

    2016-01-01

    Os mais variados sistemas sociais, biológicos, físicos, químicos e computacionais tem sido investigados pela área de Sistemas Dinâmicos para formalizar o comportamento no tempo e quantificar e qualificar variações paramétricas desses sistemas. Na biologia em particular, estudos tem mostrado que a maximização de aprendizado de um neurônio pode acontecer dentro de certas condições da sua dinâmica onde o processamento de informação é otimizado. Espera-se então que essas condições ...

  4. Effect of Traction Angle on the External Work Performed During Running in Weightlessness on a Treadmill Equipped with a Subject Loading System

    Science.gov (United States)

    Gosseye, T. P.; Willems, P. A.; Heglund, N. C.

    2008-06-01

    During long duration spaceflight, astronauts regularly run on a treadmill-gravity simulator to mitigate bone and muscle loss. This study compares the biomechanics of running on a treadmill-gravity simulator during parabolic flights with the biomechanics of running on Earth. We designed a treadmill equipped with a gravity-like subject pull-down system (SLS) and transducers that measure ground reaction forces and pull-down forces. From these signals we calculate the external work (Wext) to sustain the movements of the center of mass (COM) of the body. In weightlessness, most subjects spontaneously tilt backwards while running. This posture imitates running down a ~2° slope on Earth. Consequently, the Wext is ~15% smaller on the simulator than during level running on Earth. This effect can be avoided by mounting the SLS on mobile chariots that maintain the pull-down force vertical (as in gravity).

  5. The Effects of Simulated Weightlessness on Auditory Function and Cochlea Ultrastructure in Guinea Pig%头低位模拟失重状态对豚鼠耳蜗听功能与超微结构的影响

    Institute of Scientific and Technical Information of China (English)

    韩浩伦; 吴玮; 王鸿南; 王刚; 屈昌北; 丁瑞英; 薄少军; 李保卫

    2012-01-01

    Objective To investigate simulated weightlessness induced effects on auditory function and ultrastructure of cochlea in a head -down guinea pig model. Methods A total of 22 guinea pigs were used in this experiment. All animals had normal eardrum and car responsive before experiment. Guinea pigs were randomly divided into two groups. Sixteen guinea pigs were used for simulating weightlessness and six were served as control . Weightlessness was simulated by 30° head -down tilt for 5 days. Auditory brainstcm response (ABR) was tested and the cochlea was examined by electron microscopy and transmission electron microscopy scanning before experiment, at day 5 (at end of simulated weightlessness) and 3 days after recovery. Results Before the experiment, ABR threshold in control group (23. 48 + 6. 04 dB SPL) was not significanly different from that of in experimental group (24. 22 + 4. 04 dB SPL). After 5 days simulated weightlessness, ABR threshold in experimental group was 41. 61 + 7. 01 dB SPL which was significantly higher than the initial value (P0. 05). Simulated weightlessness for five days the outer hair cells were scattered absent, and cilia were integrated and lodged in cochlea observed with electron microscope. Under transmission electron microscope, the inner and outer hair cells in cochlea were vacuolizcd. These changes in cochlea were significantly restored after three days recovery. Conclusion Simulated weightlessness can lead to temporary damage of auditory function in guinea pigs, and the damage can be restored after 3 days of recovery, However, ultrastructurc changes in cochlea induced by simulated weightlessness can not be fully recovered 3 days later.%目的 探讨头低位模拟失重对豚鼠耳蜗听功能与超微结构的影响.方法 22只豚鼠随机分为实验组16只和对照组6只.实验组采用头低位模拟失重法,身体纵轴与水平线呈-30°,于实验前、失重5天后即刻及脱离失重 3天后分别测试豚鼠听性脑干

  6. [Effect of weightlessness on the indices of brain development (the results of pregnant rats being on the Kosmos-1514 biosatellite and research on the subsequent development of their progeny on Earth)].

    Science.gov (United States)

    Olenev, S N; Danilov, A R; Kriuchkova, T A; Sorokina, L M; Krasnov, I B

    1987-09-01

    Beginning from the 13th day of pregnancy the rats were under conditions of weightlessness of spaceflight for 6 days. After landing in 18-day-old fetuses the state of their brain development is investigated comparing to that in control animals, that are on the Earth. As demonstrates analysis of a number of morphological processes: reproduction, migration, neuronal differentiation, growth of processes, establishment of nervous connections, neuroglial interconnections and vascularization--all they under conditions of weightlessness develop rather fully. Certain deviations in vascularization (as examples the medulla oblongata and the striated tuber are taken) are observed--the amount of vessels is greater and they are thinner--and changes in migration rate of cells is demonstrated by the example of the cortical plate formation. These changes are quickly levelled during their subsequent development on the Earth.

  7. 雌激素对模拟失重及噪声条件下豚鼠听功能的影响%Effects of Estrogen on Guinea Pig Auditory Function in Simulated Spaceship Weightlessness and Noise

    Institute of Scientific and Technical Information of China (English)

    王刚; 吴大蔚; 牛聪敏; 刘钢; 吴玮; 韩浩伦; 屈昌北; 王方园; 王鸿南; 李保卫; 孟令照; 虞学军

    2013-01-01

    Objective To investigate the effects of combined simulated weightlessness and noise on auditory brainstem response thresholds in guinea pigs and the protective effects of estrogen. Methods Forty guinea pigs were randomly divided into a simulated weightlessness only group, a weightlessness with noise group, an estrogen treatment group and an estrogen prevention group. Weightlessness was simulated by posterior limb suspension, at a-30° angle between horizon and longitudi-nal axis of the body. Except for the weightlessness only group, animals in all other groups were also exposed to simulated spaceship flying and return stages noise for 5 days.Intramuscular injection of estradiol benzoate (0.08 mg/kg/day with dou-ble dose on Day 1) was administered for 3 days before experiment in the estrogen prevention group, and from the start of the experiment to 3 days after experiment in the estrogen treatment group. Auditory brainstem response (ABR) thresholds were re-corded before, at the end of and 3 days after the experiment. Results ABR thresholds were not different among the groups be-fore the experiment. ABR thresholds were different at the end of and 3 days after the experiment, with those in the estrogen treatment group being the lowest. ABR threshold differences were also seen at different times during experiment in each group. Conclusion While both weightlessness and noise can lead to damage of auditory function in guinea pigs, their combi-nation can cause even more severe damage. Estrogen appears to have protective effects against damage of auditory function caused by compound weightlessness and noise factors in space.%  目的探讨模拟失重和飞船舱内噪声复合因素对豚鼠耳蜗听性脑干反应(ABR)阈值的影响及雌激素的防护作用。方法40只豚鼠随机分为单纯失重组、失重+噪声组、雌激素治疗组、雌激素预防组各10只。后肢悬吊法模拟失重,除单纯失重组外均暴露于模拟飞船舱内在天飞

  8. 阿托伐他汀对模拟失重大鼠肺炎链球菌感染的保护作用%Protective Effect of Atorvastatin on Streptococcus Pneumoniae Infections in Rats under Simulated Weightless Condition

    Institute of Scientific and Technical Information of China (English)

    朱敏立; 王小辉; 王萍; 李月越; 崔彦

    2015-01-01

    目的 研究模拟失重状态下阿托伐他汀对上呼吸道定植菌肺炎链球菌导致肺部感染的影响,为航天员呼吸系统保护及感染治疗提供理论依据. 方法 将 Wistar大鼠40 只随机分为4 组( n=10 ) ,分别为失重感染组( weightlessness+infection, WI)、失重感染他汀组( weightlessness+infection+statin, WIS)、对照感染组( control+infec-tion, CI)及对照感染他汀组( control+infection+statin, CIS). WI和WIS组采用大鼠尾吊法模拟失重状态,CI和CIS组在鼠笼内自由活动,于第3天经气管滴入肺炎链球菌悬液0. 4 ml,复制大鼠肺部感染模型. 从实验第1天开始他汀组( WIS组、CIS组)给予阿托伐他汀10 mg/( kg·d)药物灌胃,无药物干预组( WI组、CI组)给予等量无菌注射用水灌胃.尾吊8 d后处死动物取材,测血常规、中性粒细胞黏附分子(CD11b/c),肺组织切片观察肺组织病理变化. 结果 肉眼观察4组大鼠肺组织表面出现不同程度的局部充血及点片状出血;光镜下可见肺泡腔内大量以中性粒细胞为主的炎性细胞浸润,部分肺泡结构消失. 上述改变以WI组表现最重,CIS组表现最轻,其中失重大鼠以上叶表现更为突出. 各组间白细胞、中性粒细胞值差异有统计学意义(F=3. 67,P0.05). 结论 模拟失重状态下肺炎链球菌所致肺部感染炎性反应更强,病理损害更重,阿托伐他汀对肺组织具有保护作用.%Objective To investigate the effect of Atorvastatin on pulmonary infection induced by Streptococcus pneumonia in rats under simulated weightless condition, and to provide the theoretical basis for protection of respiratory system and infection therapy for astronauts. Methods A total of 40 Wistar rats were randomly divided into weightless-ness + infection group ( WI group, n =10 ) , weightlessness + infection + statin group ( WIS group, n =10 ) , control + infection group (CI group, n=10) and control + infection + statin group (CIS group, n=10

  9. N-乙酰半胱氨酸对模拟失重大鼠肺损伤的防护作用研究%Protective Effect of N-acetylcysteine on Pulmonary Injury under Simulated Weightless Condition in Rats

    Institute of Scientific and Technical Information of China (English)

    李月越; 王萍; 朱敏立; 赵雅辉; 王小辉; 崔彦

    2015-01-01

    Objective To observe the effect of N-acetylcysteine (NAC) on pulmonary injury under simulated weightlessness in rats. Methods Tail-suspension method was used to establish the models of weightless simulation in rats. A total of 24 clean Wistar rats were randomly divided into group A, B and C ( n=8 for each group) . Group B was treated with NAC (300 mg/kg) by intragastric administration every day from the first day, while group A and C were treated with same volume of sterile water via intragastric injection. The models of weightless simulation were established in group A and B by tail-suspension method after the rats had been administrated for 2 d, while the rats in group C were free-running in the cage. The rats were killed at the end of the 7th d. The levels of superficial CD11b/c of neutrophilic granu-locyte, reactive oxygen species (ROS) concentration of neutrophilic granulocyte, contents of IL (interleukin)-10, IL-6 and TNF ( tumor necrosis factor)-αin the blood samples were detected. The superior lobe tissues of right lung were given hematoxylin and eosin stain ( HE stain) , and the pathological changes of lung tissues in slices were observed. Results In group A, under microscope, the sizes of alveoli were discrepant, the alveolar septum became wide with edema, and blood vessels were dilated and congested, and neutrophils and infiltrated lymphocytes were found in the interstitial. Simi-lar changes of group A were found in group B, but the degrees were less than those in group A, while there were no obvi-ously similar changes in group C. There were statistically significant differences in CD11b/c, ROS concentration, TNF-α, IL-10 and IL-6 (P<0. 05, P<0. 01). Conclusion NAC can alleviate inflammation and lung damages of rats under simulated weightlessness, and the antioxidation effect of NAC may play a role in protection of lung injury under weightless condition.%目的 观察N-乙酰半胱氨酸( NAC)对模拟失重状态下大鼠肺损伤的影响. 方法

  10. 模拟失重对恒河猴腰椎运动单元生物力学的影响%Effects of simulated weightlessness on biomechanics of motion unit of rhesus monkey lumbar vertebra

    Institute of Scientific and Technical Information of China (English)

    王晓平; 吴志宏; 陆明; 马培; 陈志明; 袁伟; 赵福江; 赵浩; 任冬云; 马华松

    2016-01-01

    BACKGROUND:It is generaly believed that the spine wil be extended, and vertebral muscle atrophy, bone loss of vertebral body, increased height and area of intervertebral disc, changes of composition of intervertebral disc wil occur in the condition of weightlessness. These are likely to be the cause of high incidence of low back pain. OBJECTIVE:To observe changes in lumbar spine bone microstructure analysis of simulated weightlessness on rhesus lumbar spine biomechanics. METHODS:Fourteen young rhesus monkeys were randomly divided into two groups: control group (n=7;free activities in the cage during the experiment), and experimental group (n=7; the use of head-down-10° on a special bed by bundle lying to simulate weightlessness). RESULTS AND CONCLUSION:(1) The results of Micro-CT examination: in the experimental group, structure model index in trabecular bone of increased. Trabecular bone changed from plate-like to the rod-like change. The intersection number of bone tissue in unit length to non-bone tissue declined. The average width of the canal between the trabecular bone increased, suggesting that there have been signs of osteoporosis in the experimental group. (2) Under an optical microscope, in the experimental group, bone hyperplasia line was disordered and irregular. Thick endplate trabecularbone became smal, shalow, and arranged substantialy perpendicular to the direction of trabecular bone and cartilage endplate. The closer the endplate surface, the smaler trabecular bone was. Compared with the control group, these smal trabecular bones were thin and curved. Bone marrow cavity was oval. The degree of the connection between the trabecular bones is poor, reflecting the structural characteristics of significant osteoporosis. (3) It is indicated that weightlessness affected the biomechanical properties of rhesus lumbar motion unit.%背景:一般认为在失重状态下,脊柱会出现异常延长、椎旁肌萎缩、椎体骨量丢失、椎间盘的高

  11. 尾悬吊模拟失重对雌性大鼠生殖功能的影响%Effects of weightlessness simulated by tail-ventrofixation on reproductive functions in female rats

    Institute of Scientific and Technical Information of China (English)

    贾木天; 宋昕宸; 张怡明; 王立祥

    2011-01-01

    目的:探讨模拟失重对雌性大鼠生殖功能的影响及其发生机制,为太空探索者的健康保护提供可借鉴的科学线索.方法:利用尾部悬吊法建立模拟失重状态大鼠模型;选取Wistar雌性大鼠72只,随机均分为6组,3个实验组分别为:模拟失重7 d组、模拟失重14 d组和模拟失重21 d组;3个对照组是与模拟失重组相对应的自由活动组.应用酶联免疫吸附法(ELISA)检测血清中雌二醇(E2)、卵泡刺激素(FSH)和黄体生成素(LH)水平;HE染色观察卵巢组织结构,特异性脂褐素染色观察卵巢组织衰老状况;逆转录定量PCR(qRT-PCR)技术检测细胞衰老相关分子端粒酶逆转录酶(TERT)、p53、p16、p21和P27的mRNA表达水平;免疫组织化学方法检测P53、P16、P21和P27的蛋白表达;随机取健康雄性大鼠分别与各组雌性大鼠合笼,比较生育仔鼠数量和存活率.结果:与各对照组相比,模拟失重7 d组、14 d组和21 d组大鼠血清中E2下降,FSH和LH上升(P<0.05);大鼠卵巢组织卵泡数量明显减少,卵巢组织发生细胞衰老现象,细胞衰老相关分子TERT mRNA表达被抑制(P<0.05),衰老相关的细胞周期调控分子p53、p16、p21和p27在mRNA和蛋白水平表达均升高(P<0.05).各模拟失重组雌性大鼠生育的仔鼠数量较相应的对照组明显减少(P<0.05),仔鼠存活率显著下降(P<0.01).结论:尾悬吊模拟失重导致雌性大鼠生殖功能下降,该现象与模拟失重诱导卵巢组织细胞衰老和下丘脑-垂体-卵巢轴内分泌功能紊乱相关.%AIM: To investigate the effects of weightlessness simulated by tail - ventrofixation on reproductive functions in female rats and the underlying mechanism, and to provide some clues to health protection for the space explorers.METHODS: To mimic the weightless state, the rat model of tail - ventrofixation was set up.Seventy - two female Wistar rats were randomly divided into 6 groups: 7 - day, 14 - day and 21 - day tail

  12. 骨髓腔注射骨髓间充质干细胞防治模拟失重大鼠的骨质疏松%Preventive and therapeutic effects of intra-bone marrow cavity injection of bone mesenchymal stem cells on osteoporosis in rats subjected to simulated weightlessness

    Institute of Scientific and Technical Information of China (English)

    吴礼凤; 孙平; 麦燕兴; 刘海明; 徐艳花; 杨锐; 黄震

    2012-01-01

    背景:模拟失重条件下自身骨髓间充质干细胞的增殖受到抑制,并且向成骨细胞分化的能力减弱,造成骨量减少与骨微结构的破坏,最终导致骨质疏松.目的:观察同种异体骨髓间充质干细胞骨髓腔注射对模拟失重大鼠胫骨骨密度和骨组织微结构的影响.方法:将雄性SD大鼠随机分为自由活动对照组、尾吊模拟失重组、细胞治疗组(尾吊模拟失重同时给予双侧胫骨骨髓腔注射成骨诱导的同种异体BMSCs细胞).结果与结论:与自由活动对照组相比,尾吊模拟失重组胫骨骨密度、骨小梁面积百分比、骨小梁数量和厚度均显著降低(P < 0.01),骨小梁分离度显著增加(P < 0.01).与尾吊模拟失重组相比,细胞治疗组中胫骨骨密度、骨小梁面积百分比、骨小梁数量和厚度均显著增加(P < 0.01),骨小梁分离度显著降低(P < 0.01).说明骨髓腔注射能够增加模拟失重大鼠骨密度,改善骨超微结构,减缓骨量丢失,有效防治骨质疏松.%BACKGROUND: Simulated weightlessness can inhibit the proliferation of bone marrow mesenchymal stem cells and their differentiation towards osteoblasts, which leads to osteoporosis characterized by low bone mass and microarchitectural deterioration of bone tissue.OBJECTIVE: To study the effects of intra-bone marrow cavity injection of allogeneic bone mesenchymal stem cells (BMSCs) on the bone mineral density and microarchitecture of the tibias in rats subjected to simulated weightlessness.METHODS: Male SD rats were randomly divided into three groups: normal control group, tail-suspended simulated weightlessness group, and treatment group. The bilateral tibias were subjected to intra-bone marrow cavity injection of allogeneic BMSCs while giving the tail-suspended simulated weightlessness.RESULTS AND CONCLUSION: Compared with the normal control group, the bone mineral density, percentage of trabecular area, trabecular number and trabecular thickness

  13. 模拟失重条件下长时间脑力负荷始末前额区脑电多尺度墒的变化分析%Changes of EEG Signal Multiscale Entropy at Prefrontal Cortex Area after Mental Workload Operation in Simulated Weightlessness

    Institute of Scientific and Technical Information of China (English)

    杨辉; 韦明; 牟锴钰; 田甜; 高美萍; 段玉兴

    2011-01-01

    目的 观察头低位卧床模拟失重期间脑电信号复杂度的变化,研究脑电信号多尺度熵与脑疲劳的关系.方法 8名健康男性志愿者以-15°头低位卧床(HDBR)为模拟失重,+15°头高位卧床(HUBR)为对照,志愿者静息30 min后进行2h内容为1-back图片记忆匹配VDT作业.结果 实验初HDBR条件下志愿者前额区脑电多尺度熵比HUBR条件下高,两种条件下实验末多尺度熵下降显著,HDBR条件下降幅高于HUBR条件下降幅.结论 1)志愿者短期处于模拟失重条件的应激能力会提高;2)志愿者执行长时间脑负荷任务后短时记忆能力下降,HDBR条件下志愿者执行长时间脑负荷作业更易脑疲劳;3)脑电多尺度熵随脑疲劳程度加深而逐渐降低,可用于脑疲劳的监测.%Objective To investigate the relationship between multiscale entropy ( MSE) and mental fatigue by analyzing the changes of EEG signal complexity during simulated weightlessness. Methods Eight healthy male subjects performed visual display terminal ( VDT) operation task of 1-back picture-matching during head-down bed rest (HDBR) as simulated weightlessness and head-up bed rest ( HUBR) as control respectively for 2 h. Results At the beginning of the experiment, MSE of EEG signal at prefrontal cortex area was greater in HDBR as compared with that in HUBR. At the end of the experiment, MSE decreased significantly in both conditions. Especially, the amplitude of MSE in HDBR decreased more significantly than that in HUBR. Conclusion 1) The irritability is higher when subjects are in short-term simulated weightlessness condition. 2) After long-time mental workload task, the short-term memory ability decrease. Compared with in ground condition, subjects obtain mental fatigue more easily in simulated weightlessness condition. 3 ) MSE, which decreases with the increase of mental fatigue level,could be applied to monitoring mental fatigue.

  14. 失重状态下旋转陀螺交互操作的仿真研究%Study on Real-time Interactive Simulation of Rotating Top in Weightlessness

    Institute of Scientific and Technical Information of China (English)

    安明; 刘玉庆; 周伯河; 胡福超

    2014-01-01

    针对在地面难以使用实物进行空间操作任务训练的问题,提出了一种基于人机交互和物理引擎技术的交互操作虚拟仿真方法,并实现了失重状态下旋转陀螺的虚拟操作训练。实现中首先建立航天员和陀螺的三维图形模型和用于碰撞检测的物理模型,并采用虚拟现实设备数据手套和位置跟踪仪实时跟踪获取受训人体的实时运动数据,用于交互控制虚拟航天员的运动,最终通过物理引擎及仿真算法计算失重状态下旋转陀螺的运动状态。结果显示,该方法较好地解决了旋转陀螺定轴特性仿真问题,能够满足虚拟训练的实时性和有效性要求。%To solve the problems of space operation tasks training on the ground , a virtual simulation method based on human-machine interaction technology and physics engine was proposed , which successfully accomplished the virtual training of rotating top operation in weightlessness .First, the 3D models and physical models of the astronaut and the top were built for display and collision de -tection , then the trainer ’ s real-time motion data was tracked and recorded using data gloves and mo-tion tracking device , which was used for controlling the motion of virtual astronaut , finally the rota-ting top’ s motion data was calculated using physics engine and other algorithm .The results showed that the method proposed effectively solved the problem of rotating top simulation , and it satisfied the real-time and efficiency demands of virtual training .

  15. THE PROTECTIVE EFFECTS OF SOY OLIGOPEPTIDE ON MUSCLE ATROPHY IN WEIGHTLESSNESS-SIMULATED RATS%大豆低聚肽对模拟失重大鼠肌萎缩的防护作用

    Institute of Scientific and Technical Information of China (English)

    李红毅; 白树民; 黄贱英; 龙玥姣; 韩晓龙; 朱德兵

    2012-01-01

    Objective To investigate the protective effects of soy oligopeptide (SOP)on muscle atrophy in weightlessness-simulated rats. Method Weightlessness was simulated by tail-suspended model in rats. SD rats were randomly divided into 5 groups : ground control group (GC), tail-suspended control group (TC) and 3 tail-suspended nutrition intervention groups (NS, SI, S2, S3) according to the different doses of SOP (0.03, 0.1, 0.3 g/ml). They were fed normal diets and gived water or SOP solution by intragastric administration. The biochemical indices of serum and soleus (SOL) were measured after 4 w. Results Compared with GC group, the muscle wet weight (MWW)' of SOL and the ratio of MWW to body weight in rats were significantly decreased (P<0.05), while insulinlike growth fatory (IGF-1), testosterone (TESTO), SOD, GSH-Px in serum decreased (P<0.05). The expression of atrogin-1 protein in SOL was decreased by 32% in TC group. Compared with TC group, MWW of SOL and the ratio of MWW to body weight were significantly increased (P<0.01) in NS group. The level of SOD and GSH-Px increased significantly (P<0.05)in S2, S3 group as well as GF-1 in serum in SI, S2 group, and the expression of atrogin-1 protein in SOL was decreased in all NS groups, but significantly in S3 group (P<0.05).Conclusion SOP may promote the synthesis and inhibit the breakdown of SOL protein to some extent to lessen SOL atrophy in tail-suspended rats. The possible mechanism was through stimulating the secretion of anabolic hormone and the antioxidate ability and inhibiting the expression of atrogin-1 protein.%目的 观察大豆低聚肽对模拟失重条件下大鼠肌萎缩的对抗效果.方法 尾部悬吊法建立模拟失重模型,SD雄性大鼠随机分为地面对照组(GC组)、尾吊对照组(TC组)及尾吊营养干预组,按大豆低聚肽低、中、高剂量0.03,0.1,0.3 g/ml,(S1、S2、S3),GC组和尾吊营养干预组经人工灌胃的方式分别给予对应剂量的纯净水

  16. Prolonged weightlessness affects promyelocytic multidrug resistance.

    Science.gov (United States)

    Piepmeier, E H; Kalns, J E; McIntyre, K M; Lewis, M L

    1997-12-15

    An immortalized promyelocytic cell line was studied to detect how doxorubicin uptake is affected by microgravity. The purpose of this experiment was to identify the effect that microgravity may have on multidrug resistance in leukocytes. HL60 cells and HL60 cells resistant to anthracycline (HL60/AR) were grown in RPMI and 10% FBS. Upon reaching orbit in the Space Shuttle Endeavour, the cells were robotically mixed with doxorubicin. Three days after mixing, cells were fixed with paraformaldehyde/glutaraldehyde. Ground control experiments were conducted concurrently using a robot identical to the one used on the Shuttle. Fixed cells were analyzed within 2 weeks of launch. Confocal micrographs identified changes in cell structure (transmittance), drug distribution (fluorescence), and microtubule polymerization (fluorescence). Flight cells showed a lack of cytoskeletal polymerization resulting in an overall amorphic globular shape. Doxorubicin distribution in ground cells included a large numbers of vesicles relative to flight cells. There was a greater amount of doxorubicin present in flight cells (85% +/- 9.7) than in ground control cells (43% +/- 26) as determined by image analysis. Differences in microtubule formation between flight cells and ground cells could be partially responsible for the differences in drug distribution. Cytoskeletal interactions are critical to the function of P-glycoprotein as a drug efflux pump responsible for multidrug resistance.

  17. Clinical models of cardiovascular regulation after weightlessness

    Science.gov (United States)

    Robertson, D.; Jacob, G.; Ertl, A.; Shannon, J.; Mosqueda-Garcia, R.; Robertson, R. M.; Biaggioni, I.

    1996-01-01

    After several days in microgravity, return to earth is attended by alterations in cardiovascular function. The mechanisms underlying these effects are inadequately understood. Three clinical disorders of autonomic function represent possible models of this abnormal cardiovascular function after spaceflight. They are pure autonomic failure, baroreflex failure, and orthostatic intolerance. In pure autonomic failure, virtually complete loss of sympathetic and parasympathetic function occurs along with profound and immediate orthostatic hypotension. In baroreflex failure, various degrees of debuffering of blood pressure occur. In acute and complete baroreflex failure, there is usually severe hypertension and tachycardia, while with less complete and more chronic baroreflex impairment, orthostatic abnormalities may be more apparent. In orthostatic intolerance, blood pressure fall is minor, but orthostatic symptoms are prominent and tachycardia frequently occurs. Only careful autonomic studies of human subjects in the microgravity environment will permit us to determine which of these models most closely reflects the pathophysiology brought on by a period of time in the microgravity environment.

  18. Neuromuscular adaptation to actual and simulated weightlessness

    Science.gov (United States)

    Edgerton, V. R.; Roy, R. R.

    1994-01-01

    The chronic "unloading" of the neuromuscular system during spaceflight has detrimental functional and morphological effects. Changes in the metabolic and mechanical properties of the musculature can be attributed largely to the loss of muscle protein and the alteration in the relative proportion of the proteins in skeletal muscle, particularly in the muscles that have an antigravity function under normal loading conditions. These adaptations could result in decrements in the performance of routine or specialized motor tasks, both of which may be critical for survival in an altered gravitational field, i.e., during spaceflight and during return to 1 G. For example, the loss in extensor muscle mass requires a higher percentage of recruitment of the motor pools for any specific motor task. Thus, a faster rate of fatigue will occur in the activated muscles. These consequences emphasize the importance of developing techniques for minimizing muscle loss during spaceflight, at least in preparation for the return to 1 G after spaceflight. New insights into the complexity and the interactive elements that contribute to the neuromuscular adaptations to space have been gained from studies of the role of exercise and/or growth factors as countermeasures of atrophy. The present chapter illustrates the inevitable interactive effects of neural and muscular systems in adapting to space. It also describes the considerable progress that has been made toward the goal of minimizing the functional impact of the stimuli that induce the neuromuscular adaptations to space.

  19. Antigravity Suits For Studies Of Weightlessness

    Science.gov (United States)

    Kravik, Stein E.; Greenleaf, John

    1992-01-01

    Report presents results of research on use of "antigravity" suit, one applying positive pressure to lower body to simulate some effects of microgravity. Research suggests lower-body positive pressure is alternative to bed rest or immersion in water in terrestrial studies of cardioregulatory, renal, electrolyte, and hormonal changes induced in humans by microgravity.

  20. The Beginnings of Airborne Weightlessness Research.

    Science.gov (United States)

    1985-01-01

    in Mendoza. That was the Fiat G 55-B which was similar to the Messerschmitt 109, with which I was familiar . I4 b 1 4 I ... L - PS. NA DC-850 16-60 C...Vol- L.: Sulla fisiopatologia durante il volo ntee suoreths ofathesemissiwasfohotem- nello spazio. Rivista Medicina Acvo- unteered for this task, wl

  1. How Can "Weightless" Astronauts Be Weighed?

    Science.gov (United States)

    Carnicer, Jesus; Reyes, Francisco; Guisasola, Jenaro

    2012-01-01

    In introductory physics courses, within the context of studying Newton's laws, it is common to consider the problem of a body's "weight" when it is in free fall. The solution shows that the "weight" is zero and this leads to a discussion of the concept of weight. There are permanent free-fall situations such as astronauts in a spacecraft orbiting…

  2. 模拟失重后高+Gx暴露对猴腮腺组织唾液淀粉酶表达的影响%Effects of the high + Gx exposure after simulated weightlessness on the expression of salivary alpha-amylase in parotid gland of monkey

    Institute of Scientific and Technical Information of China (English)

    郭杨; 牛忠英; 汤楚华; 张建中; 郑燕华

    2015-01-01

    Objective To explore the effects of the high + Gx exposure after 30-d simulated weightlessness on salivary alpha-amylase (sAA) expression in rhesus monkey parotid,in order to provide experimental reference for maintaining astronauts' oral health and health care.Methods According to the literature review and the actual situation of spaceflight,twenty-three healthy male rhesus monkeys were randomly divided into four groups:①control group (n=3);②30-d simulated weightlessness group (n=3);③+ 13 Gx/230 s group (n=3);④group D:high +Gx after 30 d simulated weightlessness exposure group (n =14).The group D was further divided into four subgroups according to the +Gx peak load:-+-11 Gx/270 s (group D1,n=3),+13 Gx/230 s (group D2,n=4),+15 Gx/200 s (group D3,n=4),+-13 Gx/230 s and 9 d's recovery (group D4,n=3).For building weightlessness model,the rhesus monkeys were put on bed with-10° head down tilt position to simulate the microgravity environment.The rhesus monkeys were fixed in Model-58 animal centrifuge exposing to high +Gx environment that was built by computer controlled para-hypergravity profile.Salivary glands were collected at the second day of experimental operation.The expression of a-amylase on protein and mRNA level was separately detected by Western blot and quantitative realtime polymerase chain reaction (qRT-PCR).All of the statistical analysis data were performed by using SPSS 17.0.Results On protein level,Western blot analysis showed that sAA expression in other experimental groups decreased significantly as compared with that in control group (F=80.381,P<0.01).In groups of high +Gx exposure after simulated weightlessness,sAA expression showed a decreasing trend with the +Gx increase.However it rose again by 9-d recovery.On mRNA level,it displayed a conformably trend with that of protein level.Conclusions High +Gx exposure after 30-d simulated weightlessness can down-regulate sAA expression in parotid gland of rhesus monkey,and may cause the

  3. Effect of a Chinese herbal prescription on femur calcium deposition in rats under simulated weightlessness: by using 41 Ca tracing-accelerator mass spectrometry analysis%中药干预模拟失重大鼠股骨外源钙沉积研究

    Institute of Scientific and Technical Information of China (English)

    胡素敏; 周鹏; 姜山; 何明; 傅骞; 杨佳佳; 高学敏

    2009-01-01

    To study the effect of a Chinese herbal prescription on external calcium deposition to weight-bearing bone in simula-ted weightlessness rats. Method:Twenty-one male Wistar rats were divided into 3 groups: control group, tail suspension group, tail suspension with Chinese medicine group which takes a Chinese herbal prescription extract ( containing Radix Rehmanniae Preparata,Radix Acanthopanacis Bidentatae, Radix Astragali, Radix Angelicae Sinensis, Concha Ostreae prepared by acetic acid) by intragastric administration. After 1 week adaption, there start off 3 weeks simulated weightlessness by tail suspension. At the eleventh day of simu-lated weightlessness , every rat was given one equal dose of ~(41)Ca tracer by intragnstric administration. Right femurs were separated as experiment over, and the ratio of ~(41)Ca to ~(40) Ca ( ~(41) Ca / ~(40) Ca) was measured by accelerator mass spectrometry ( AMS ) , while total femur calcium was measured by inductively coupled plasma-atomic emission spectroscopy (ICP-AES). Femur ~(41) Ca deposition amount (DA) and femur ~(41) Ca deposition ratio (DR) were calculated. Result:The results showed that compared with control group, ~(41) Ca / ~(40) Ca de-creased significantly (P <0.001 ) in tail suspension group, while in tail suspension with Chinese medicine group, it significantly in-creased ( P < 0.05 ). DA and DR were both decreased significantly ( P < 0.001 ) in tail suspension group, but no significant change in tail suspension with Chinese medicine group as compared with control group. Compared with tail suspension group, DA and DR in-creased significantly (P < 0. 001 ) in tail suspension with Chinese medicine group. Conclusion:Simulated weightlessness by tail sus-pension can cause decreased deposition of external calcium to weight-bearing bone, and the Chinese herbal prescription in this trial is effective to prevent the decrease. Moreover, multiple mechanisms may contribute to weightlessness induced osteoporosis, besides

  4. 模拟失重大鼠肺组织显微结构和一氧化氮合酶表达的动态变化%Dynamic changes of microscopical structure and NOS expression in rat lung tissues under simulated weightlessness

    Institute of Scientific and Technical Information of China (English)

    汪德生; 袁明; 李志利; 王惠娟; 李天志; 刘长庭; 乔健

    2008-01-01

    目的 观察模拟失重对大鼠肺组织显微结构及其一氧化氮合酶(NOS)表达的影响,为模拟失重时肺组织的适应机制研究积累资料.方法 采用Wistar雄性大鼠-30°尾部悬吊模拟失重生理效应.常规光镜和免疫组织化学方法 观察悬吊7 d组(TS7)、14 d组(TS14)及对照组(Con)肺组织显微结构和结构型NOS(cNOS)、诱导型NOS(iNOS)表达.结果 TS7组大鼠出现肺实变、肺水肿、支气管黏膜内淋巴细胞浸润、肺泡内有红细胞及肺泡融合.TS14组大鼠肺病变较TS7组大鼠明显加重,表现为肺泡融合增多、肺泡内更多红细胞和肺泡壁增厚.各组大鼠肺组织cNOS表达区域主要为支气管上皮细胞、血管内皮细胞和平滑肌细胞,各组间表达水平无统计学差异.iNOS表达在TS7、TS14组血管内皮细胞和平滑肌细胞表达显著增多,其中TS14组血管内皮细胞表达量高于TS7组.结论 模拟失重大鼠肺组织形态学变化可能与肺循环iNOS表达增加有关.%Objective To observe dynamic changes of microscopical structure and nitric oxide synthase(NOS) expression in rat lung tissues under simulated weightlessness,and to collect the data for studies of the adaptive mechanism of local regulation in lung tissues. Methods Wistar male rats were -30° tail suspended to simulate the physiological effects of weightlessness. The microscopical structure,constitutive NOS(cNOS)and inducible NOS(iNOS)expression of rat lung tissues in control group(Con),7-day tail suspension group(TS7) and 14-day tail suspension group(TS14) were respectively observed with routine microscope and immunohistochemistry. Results The solid edema of lungs appeared in TS7 rats,accompanied with lymphocyte soakage in bronchial mucous membranes,red blood cells in alveolus and alveolar amalgamation. The pathological change was more obvious in the TS14 group than that in TS7 group,accompanied with more alveolar amalgamation,more red blood cells in alveolus and

  5. Effects of simulated weightlessness on Nissl body morphology and GDNF in DRG of male rats%模拟失重对雄性大鼠背根神经节尼氏小体形态和胶质细胞源性神经营养因子的影响

    Institute of Scientific and Technical Information of China (English)

    任宁涛; 崔赓; 张恒; 李洁; 雷伟; 刘宁; 毕龙; 吴子祥; 张然; 张永刚

    2015-01-01

    Objective To investigate the effect of simulated weightlessness on dorsal root ganglia (DRG) and GDNF in rat model. Methods Eighty male Sprague-Dawley rats were randomly divided into HU group (n=40) and normal control (NC) group (n=40). The experiment lasted for 4 weeks, then L5 DRG was excised, toluidine blue staining was used to detect the changes of nissl body morphology, and GDNF was detected using immunohistochemistry method. GDNF protein expression was measured by Western-blot and GDNF mRNA expression was measured by RT-PCR.Results Nissl body staining showed that, compared with NC group, nissl bodies were stained light, smaller and scattering distribution in HU group. Immunohistochemistry revealed that the number of GDNF and IOD value reduced significantly in HU group (P<0.05). Western-blot showed that GDNF protein expression in HU group were significantly lower than NC group (P<0.05). mRNA expression of GDNF decreased significantly in HU group (P<0.05). Conclusion Four weeks of stimulated weightlessness can cause damaged changes in DRG nissl body morphology and reduction of the number, protein expression and mRNA expression of GDNF, which suggests that simulated weightlessness can cause damage changes in rat dorsal root ganglion.%目的:探讨模拟失重对背根神经节(dorsal root ganglia,DRG)及胶质细胞源性神经营养因子(glial cell line-derived neurotrophic factor,GDNF)的影响。方法健康雄性SD大鼠80只,随机分为尾部悬吊(HU)组(n=40)和正常对照(NC)组(n=40),4周后处死各组大鼠,取腰5背根神经节,甲苯氨兰染色观察背根神经节内尼氏小体变化,免疫组化观察GDNF的变化, Western-blot方法检测GDNF的蛋白表达,实时PCR检测GDNF mRNA表达情况。结果与NC组相比,HU组尼氏体染色浅,尼氏体变小,弥散分布。免疫组化结果显示,与NC组比较,HU组GDNF量及积分光密度(integral optical density,IOD)值减少(P<0.05)。Western-blot结果

  6. Changes in optical micrograph and electron micrograph to the mucosa of small intestine of the rats under simulated weightlessness%模拟失重状态下大鼠小肠黏膜光镜及电镜的形态学改变

    Institute of Scientific and Technical Information of China (English)

    陈英; 杨春敏; 王萍; 毛高平; 任力

    2008-01-01

    Objective To investigate if the simulated weightlessness can induce the change in mucosa of small intestinal of tail-suspended rats. Methods Ultrastructural changes of the mucous of small intestinal of 14-day tail-suspended rats (SUS-14 d), 21-day tail-suspended rats (SUS-21 d) and controlled rats (CON) were studied by optical microscope and transmission electron microscope. Results By optical micrograph, the number of villius and crypt of SUS-14 d and SUS-21 d group were fewer than that of CON group. The height and width of villus of SUS-14 d and SUS-21 d group were lower than those in CON group (F=294.24, 328. 63, P<0. 01). The depth of crypt of SUS-14 d and SUS-21 d group were greater than that in CON group (F=60. 5, P<0.01). The ratios of Height/Width and Height/Depth of SUS-14 d and SUS-21 d group were less than that of CON group (F=246.69, 3. 68, P<0. 05). Moreover, by electron micrograph, the number of microvillus was fewer than that in CON group too. The height, superficial area of microvillus and the thickness of icing in SUS-14 d and SUS-21 d group were significantly less than those in CON group (F=234. 90, 138.07, 195. 35, P<0.01). Contrarily, the width of microvillus and the space between every two microvilli in SUS-14 d and SUS-21 d group were greater than those in CON group. Conclusion Results indicate that simulated weightlessness for 14 days and 21 days could lead to the mucosal villi of small intestinal fewer, shorter and wider according to optical micrograph. The analysis also shows that the height and surface area of microvillus are significantly decreased under simulated weightlessness aecording to electron micrograph. These data probably provide important theoretical evidence for finding the reason of aerial diseases such as diarrhea, dyspepsia and disorders of digestion, etc.%目的 以尾部悬吊大鼠模型模拟失重的影响,探讨模拟失重是否可引起小肠黏膜的改变. 方法 用光学显微镜和扫描电镜,观

  7. 模拟失重对大鼠承重骨骨髓基质细胞数量及体外成骨能力的影响%Effects of simulated weightlessness on bone marrow stromal cell count and osteogentic capacity of weight bearing bone in rats

    Institute of Scientific and Technical Information of China (English)

    付崇建; 郁冰冰; 杨连甲; 曹新生; 张立藩

    2007-01-01

    背景:骨组织在特殊物理环境如失重环境下,代谢活动会发生显著的变化,而成骨细胞是骨代谢和骨形成的核心部分,其对重力环境的变化敏感.目的:观察模拟失重条件对大鼠股骨骨髓基质细胞数量体外成骨能力的影响,揭示骨丢失的机制.设计:随机配对,对照实验.单位:解放军第四军医大学航空航天医学系和口腔医学院病理科.材料:选用20只成年健康雄性SD大鼠.实验开始当日按体质量随机分为对照组和悬吊组,每组10只.碱性磷酸酶试剂盒由北京中生生物工程高技术公司生产.方法:实验于1999-11/2000-07在解放军第四军医大学口腔医学院病理科完成.将SD大鼠随机配对分为鼠尾悬吊组和对照组,每组10只.悬吊组大鼠做尾部悬吊28 d,大鼠始终保持30°头低位及后肢自由悬垂不负重状态.对照组正常饲养.实验期满,取股骨,将股骨骨髓基质细胞进行原代和传代细胞培养.主要观察指标:采用细胞计数法和噻唑蓝法绘制原代和传代培养细胞的生长曲线,进行碱性磷酸酶活性及体外矿化小结形成量的检测.结果:①碱性磷酸酶活性:原代和传代培养悬吊组低于对照组,差异有显著性意义(P<0.05).②钙化小结形成数:悬吊组少于对照组,差异有显著性意义(P<0.05).③细胞生长:原代和传代股骨间充质细胞的生长曲线呈"S"形,悬吊组和对照组细胞倍增时间相近.④股骨骨髓基质细胞数:原代细胞培养系中,悬吊组比对照组约少50%(P<0.05).结论:模拟失重条件下,大鼠骨髓基质细胞数明显减少,后肢承重骨成骨细胞数减少,体外成骨能力降低.%BACKGROUND: Under specially physical environment, for example weightlessness, metabolism of bone tissue may have remarkable changes; however, osteoblast is a core of bone metabolism and bone formation, so it is very sensitive to changes of gravity environment.OBJECTIVE: To observe the effects

  8. Dynamics of transitions between capillary stable states under weightlessness

    Science.gov (United States)

    Srikanth, Praveen

    The study of two phase systems with one of the phases obstructing the other is of importance in a lot of fields. Liquid droplets in airways and air bubbles in the blood stream both fall under this category of problems. Helium bubbles in hydrazine fuel lines of satellites also have been found to cause frequent thruster shutdown and also seriously affect spacecraft control. Studies have been carried out until now to look at static equilibrium topologies and stability of such two phase systems in straight, bent and laterally compressed capillaries. In this investigation we look at the dynamics of the transitions between the stable topologies identified for a straight cylindrical capillary. The break up of the interface could adversely affect system performance. OpenFOAM is used to compute transitions from a stable droplet to a plug or the reverse by suitably adding or removing the obstructing phase through inlet patches on the wall of the cylinder. The main parameters presented are the non-dimensional energy, non-dimensional transition times, non-dimensional transition volumes and the general dynamics of the transitions itself. Before computing transitions the static equilibrium topologies computed by OpenFOAM are compared with those predicted by Surface Evolver and are found to be within acceptable deviations. The grid dependence of these transitions has also been studied. Transitions are computed for contact angles in the range of 10° to 170°. Different modes of transitions are observed depending on the contact angle of the case for both the types of transitions. The transition volumes are compared to the volume of existence limits for the corresponding initial topology at a particular contact angle for both the transitions.

  9. Effects of spaceflight and simulated weightlessness on longitudinal bone growth

    Science.gov (United States)

    Sibonga, J. D.; Zhang, M.; Evans, G. L.; Westerlind, K. C.; Cavolina, J. M.; Morey-Holton, E.; Turner, R. T.

    2000-01-01

    Indirect measurements have suggested that spaceflight impairs bone elongation in rats. To test this possibility, our laboratory measured, by the fluorochrome labeling technique, bone elongation that occurred during a spaceflight experiment. The longitudinal growth rate (LGR) in the tibia of rats in spaceflight experiments (Physiological Space Experiments 1, 3, and 4 and Physiological-Anatomical Rodent Experiment 3) and in two models of skeletal unloading (hind-limb elevation and unilateral sciatic neurotomy) were calculated. The effects of an 11 day spaceflight on gene expression of cartilage matrix proteins in rat growth plates were also determined by northern analysis and are reported for the first time in this study. Measurements of longitudinal growth indicate that skeletal unloading generally did not affect LGR, regardless of age, strain, gender, duration of unloading, or method of unloading. There was, however, one exception with 34% suppression in LGR detected in slow-growing, ovariectomized rats skeletally unloaded for 8 days by hind-limb elevation. This detection of reduced LGR by hind-limb elevation is consistent with changes in steady-state mRNA levels for type II collagen (-33%) and for aggrecan (-53%) that were detected in rats unloaded by an 11 day spaceflight. The changes detected in gene expression raise concern that spaceflight may result in changes in the composition of extracellular matrix, which could have a negative impact on conversion of growth-plate cartilage into normal cancellous bone by endochondral ossification.

  10. Vitamin D in Real and Simulated Weightlessness: Implications for Earth

    Science.gov (United States)

    Rice, Barbara L.; Zwart, Sara R.; Smith, Scott M.

    2006-01-01

    Vitamin D deficiency has reemerged as a public health concern in the United States. It is also a concern for astronauts because spacecraft are shielded from ultraviolet light, leaving diet as the sole source of vitamin D. We report here the findings from four studies: one evaluation of astronauts before and after 4- to 6-month missions to the International Space Station, and the other three from a ground-based analog for space flight, long-term bed rest. For the space flight study, blood samples were collected before the flight and within hours of landing after it. Crewmembers (n = 11) were provided vitamin D supplements (as cholecalciferol (10 g/d) throughout the mission. The average number of vitamin D supplements reported to be consumed per week was 5.7 plus or minus 4.0. The vitamin D status indicator serum 25-hydroxycholecalciferol was 25% less after landing (48 plus or minus 20) than before flight (63 plus or minus 16) (P less than 0.01). A series of three studies was undertaken to evaluate nutritional changes during and after 60 or 90 days of -6 deg. head-down-tilt bed rest. A total of 11 subjects (8 M, 3 F; age 26-55 y) participated in the studies. Blood and urine were collected twice before bed rest and once per month during bed rest. During bed rest the average dietary intake of vitamin D for the three studies was 4.84 plus or minus 0.16 (study 1), 6.24 plus or minus 0.81 (study 2), and 7.16 plus or minus 1.40 (study 3) micrograms/day. In study 1 only, subjects were given a daily supplement of 10 g vitamin D (as ergocalciferol). Data were analyzed using repeated-measures ANOVA. In the first study, 7 days after the end of the bed rest, serum 25-hydroxycholecalciferol was 30% less than it was before bed rest (p less than 0.05). In the second and third studies, during or after bed rest the serum 25-hydroxycholecalciferol concentration was not significantly different from its concentration before bed rest. These data demonstrate that vitamin D intake is critical for individuals not exposed to the sun. Although we studied astronauts and healthy subjects in bed rest, the implications of our results also apply to people living in northern latitudes and others who receive little exposure to sunlight, such as elderly people who seldom go outdoors. The inability of supplements to maintain vitamin D status is also an important finding, and highlights the need for careful food selection to ensure adequate vitamin D intake.

  11. Functional and cellular adaptation to weightlessness in primates

    Science.gov (United States)

    Bodine-Fowler, Sue C.; Pierotti, David J.; Talmadge, Robert J.

    1995-01-01

    Considerable data has been collected on the response of hindlimb muscles to unloading due to both spaceflight and hindlimb suspension. One generalized response to a reduction in load is muscle fiber atrophy, although not all muscles respond the same. Our understanding of how muscles respond to microgravity, however, has come primarily from the examination of hindlimb muscles in the unrestrained rate in space. The non-human primate spaceflight paradigm differs considerably from the rodent paradigm in that the monkeys are restrained, usually in a sitting position, while in space. Recently, we examined the effects of microgravity on muscles of the Rhesus monkey by taking biopsies of selected hindlimb muscles prior to and following spaceflights of 14 and 12 day durations (Cosmos 2044 and 2229). Our results revealed that the monkey's response to microgravity differs from that of the rat. The apparent differences in the atrophic response of the hindlimb muscles of the monkey and rat to spaceflight may be attributed to the following: (1) a species difference; (2) a difference in the manner in which the animals were maintained during the flight (i.e., chair restraint or 'free-floating'); and/or (3) an ability of the monkeys to counteract the effects of spaceflight with resistive exercise.

  12. Equipment for surgical interventions and childbirth in weightlessness

    Science.gov (United States)

    Mutke, H. G.

    A transparent plastic sack has been devised for surgical interventions in space. Fixed airtight on the patient, containing sterilized medical equipment and comprising long sleeves for the operations, it retains all its contents for the rest of the flight.

  13. Effect of Weightlessness on Neutrophils and Lymphocytes of Rats

    Directory of Open Access Journals (Sweden)

    Khusi Muhammad Saqib, Zia-ur-Rahman1 and Saeed Ahmad Nagra2

    2012-01-01

    Full Text Available In the present study, two hundreds and forty healthy albino young (n=120 and old (n=120 rats were used during winter and summer season. Rats were divided into four groups in each season i.e. young and old, consisting of male (n=30 and female (n=30 in each age category. In each age  sex matched rats, three subgroups were made and have been given the name as cage control (CC group, horizontal restrained group (HR and head down suspended (HDS group. For winter season, the room temperature of experimental period ranged from 20 to 23°C and for summer season, the experimental room temperature ranged from 30 to 33°C. A 12 hours light/12 hours dark cycle with ad libitum food offered each day to an individual rats as well as fresh water (at normal temperature were provided every day from 9-10 h (morning Rats were decapitated on day 7th (n=5 and day 28th (n=5 of experimental period from all groups to collected the blood in a hepranized tubes for the estimation of lymphocytes and neutrophils. Appropriate statistical analysis was performed to estimate the difference between age, days, treatments and their possible interactions during each season. During winter and summer seasons, male and female rats did show a significant decrease in lymphocytes, however a significant increase in the neutrophils percent was also observed in the HR and HDS groups. During summer, a significant increase in neutrophils and a decrease in lymphocytes were observed in male and female rats of HR and HDS groups.

  14. Effects of Weightlessness of Aurelia Ephyra Differentiation and Statolith Synthesis

    Science.gov (United States)

    Spangenberg, D. B.

    1985-01-01

    Aurelia polyps are especially suited for space flight experiments because they are very small (2 to 4 mm), form ephyrae with gravity sensing structures in 6 to 7 days, and can be reared easily and inexpensively in the laboratory. During iodine-induced metamorphosis ephyrae develop in sequential order from the oral to the aboral end of the polyps. Eight sites of gravity receptors (rhopalia) form per ephyra. These structures have sacs of statoliths at their distal end, which are composed of calcium sulfate dihydrate. Only one statolith forms per cell (statocyte) and the cells collect at the distal end of the rhopalia forming statocysts. Rhopalia with statocysts are necessary for the righting reflex of swimming medusae. Using the Aurelia Metamorphosis Test System (Spangenberg, 1984) for the past eight months, the effects of clinostat rotation in the horizontal and verticall planes on the development of ephyrae and the synthesis of their statoliths were investigated.

  15. Artificial Gravity as a Bone Loss Countermeasure in Simulated Weightlessness

    Science.gov (United States)

    Smith, S. M.; Zwart, S. R.; Crawford, G. E.; Gillman, P. L.; LeBlanc, A.; Shackelford, L. C.; Heer, M. A.

    2007-01-01

    The impact of microgravity on the human body is a significant concern for space travelers. We report here initial results from a pilot study designed to explore the utility of artificial gravity (AG) as a countermeasure to the effects of microgravity, specifically to bone loss. After an initial phase of adaptation and testing, 15 male subjects underwent 21 days of 6 head-down bed rest to simulate the deconditioning associated with space flight. Eight of the subjects underwent 1 h of centrifugation (AG, 1 gz at the heart, 2.5 gz at the feet) each day for 21 days, while 7 of the subjects served as untreated controls (CN). Blood and urine were collected before, during, and after bed rest for bone marker determinations. At this point, preliminary data are available on the first 8 subjects (6 AG, and 2 CN). Comparing the last week of bed rest to before bed rest, urinary excretion of the bone resorption marker n-telopeptide increased 95 plus or minus 59% (mean plus or minus SD) in CN but only 32 plus or minus 26% in the AG group. Similar results were found for another resorption marker, helical peptide (increased 57 plus or minus 0% and 35 plus or minus 13% in CN and AG respectively). Bone-specific alkaline phosphatase, a bone formation marker, did not change during bed rest. At this point, sample analyses are continuing, including calcium tracer kinetic studies. These initial data demonstrate the potential effectiveness of short-radius, intermittent AG as a countermeasure to the bone deconditioning that occurs during bed rest.

  16. Bone loss during simulated weightlessness - Is it glucocorticoid mediated?

    Science.gov (United States)

    Bikle, D. D.; Halloran, B. P.; Cone, C. M.; Morey-Holton, E.

    1985-01-01

    Elevating the hindquarters of a rat by the tail unweights the hind limbs but maintains normal weight-bearing by the forelimbs. This maneuver leads to a decrease in bone mass and calcium content in the unweighted bones (e.g., tibia and L1 vertebra), but not in the normally weighted bones (e.g., humerus and mandible). Potentially, the stress of the maneuver, mediated by increased glucocorticoid production and secretion, could explain the decreased bone formation, rather than the skeletal unweighting per se. To test this possibility, the effects of adrenalectomy on the response of bone to the unweighting of the hind limbs of normal rats were evaluated.

  17. A monkey metabolism pod for space-flight weightlessness studies.

    Science.gov (United States)

    Pace, N.; Rahlmann, D. F.; Kodama, A. M.; Mains, R. C.; Grunbaum, B. W.

    1973-01-01

    The system described will permit quantitative physiological studies in adult monkeys, weighing from 8 to 14 kg, during future space flights. The system comprises a fiberglass pod containing a comfortable restraint couch for the animal. The pod is divided into upper and lower halves. When the monkey occupies the couch, a rubber belly-band forms a gas seal between the upper and lower portions of the animal. The upper-pod ventilating air stream is monitored for the partial pressures of oxygen, carbon dioxide, nitrogen, and water to permit continuous metabolic gas-exchange measurements for computation of metabolic energy expediture. The lower pod is lined with ashless filter paper for excreta collection.

  18. Functional and cellular adaptations of rodent skeletal muscle to weightlessness

    Science.gov (United States)

    Caiozzo, Vincent J.; Haddad, Fadia; Baker, Michael J.; Baldwin, Kenneth M.

    1995-01-01

    This paper describes the affects of microgravity upon three key cellular levels (functional, protein, and mRNA) that are linked to one another. It is clear that at each of these levels, microgravity produces rapid and substantial alterations. One of the key challenges facing the life science community is the development of effective countermeasures that prevent the loss of muscle function as described in this paper. The development of optimal countermeasures, however, awaits a clearer understanding of events occurring at the levels of transcription, translation, and degradation.

  19. Effects of Weightlessness on Vestibular Development of Quail

    Science.gov (United States)

    Fritzsch, Bernd; Bruce, Laura L.

    1999-01-01

    The data confirm previous findings that quail embryos can, under proper circumstances, develop until hatching in microgravity. There were no gross abnormalities in the few ears of the late embryos (we received 3 ears at E14.5 and 4 ears at E16.5). Due to inadequate numbers of samples returned and their fully insufficient fixation, no conclusions could be reached that warrant any publications.

  20. Faraday instability in a near-critical fluid under weightlessness.

    Science.gov (United States)

    Gandikota, G; Chatain, D; Amiroudine, S; Lyubimova, T; Beysens, D

    2014-01-01

    Experiments on near-critical hydrogen have been conducted under magnetic compensation of gravity to investigate the Faraday instability that arises at the liquid-vapor interface under zero-gravity conditions. We investigated such instability in the absence of stabilizing gravity. Under such conditions, vibration orients the interface and can destabilize it. The experiments confirm the existence of Faraday waves and demonstrate a transition from a square to a line pattern close to the critical point. They also show a transition very close to the critical point from Faraday to periodic layering of the vapor-liquid interface perpendicular to vibration. It was seen that the Faraday wave instability is favored when the liquid-vapor density difference is large enough (fluid far from the critical point), whereas periodic layering predominates for small difference in the liquid and vapor densities (close to the critical point). It was observed for the Faraday wave instability that the wavelength of the instability decreases as one approaches the critical point. The experimental results demonstrate good agreement to the dispersion relation for zero gravity except for temperatures very close to the critical point where a transition from a square pattern to a line pattern is detected, similarly to what is observed under 1g conditions.

  1. Effects of Head-down Bed Rest Stimulated Weightlessness on Perceptual Accuracy and Conflict Control Function%头低位卧床模拟失重对知觉正确性和冲突控制能力的影响

    Institute of Scientific and Technical Information of China (English)

    程真波; 李冬冬; 谈诚; 杜博琪; 罗跃嘉; 陈文娟; 陈晓萍; 白延强; 黄宇霞

    2013-01-01

    目的 探究45 d-6°头低位卧床中知觉正确性和冲突控制能力受到的影响和变化规律.方法 采用头低位卧床模拟失重,选取视觉后向掩蔽任务和刺激-反应冲突任务,在卧床实验6个不同阶段(卧床前第6天,卧床中第11,20,30和40天,以及卧床后第8天)对16名志愿者进行重复测试.结果 在知觉正确性测试中,志愿者在卧床第11天的正确率显著提高(P>0.05),在卧床第32天时达到并维持在一个较高的水平直至卧床后第8天最后一次测试.在刺激-反应冲突任务中,在卧床第32天测试中出现显著的促进作用(P>0.05),并在起床后明显下降.结论 头低位卧床对认知功能不会造成明显损害,甚至可能有促进作用;知觉正确性和反应协调性的变化趋势在卧床早期具有一定的相似性;在卧床结束后冲突控制能力降低,但知觉正确性未受影响.%Objective To investigate the influence of 45 d of-6° head-down bed rest ( HDBR) on perceptual accuracy and conflict control function. Methods Sixteen healthy subjects participated in this experiment. Six test sessions were conducted; on the 6th day before bed rest, on the 11th, 20th, 32nd and 40th day of bed rest and on the 8 th day of recovery after HDBR. The visual backward masking task and the stimulus-response conflict task were adopted to test the subjects' perceptual accuracy and conflict control function separately. Results In the visual backward masking task, the accuray on the 11 th day of HDBR was increased significantly as compared with that in pre-HDBR(P >0. 05). And the performance was reached to a higher level on the 32nd day of HDBR, following a period of performance stabilization until post-HDBR. In the stimulus-response conflict task, there was a significant improvement on the 32nd day of HDBR( P > 0. 05). But the performance was damaged apparently in post-HDBR. Conclusion Simulated weightlessness is of no significant negative influence on

  2. A study on the changes of bone structure and properties in female rats under simulated weightlessness as osteoporosis models%模拟失重状态下雌性大鼠骨质疏松模型骨结构及性能变化研究

    Institute of Scientific and Technical Information of China (English)

    张恒; 任宁涛; 李洁; 雷伟; 刘宁; 张永刚; 张然; 杨彦玲; 崔赓

    2015-01-01

    Objective To study the changes of bone mineral density ( BMD ) of cancellous bone, trabecular bone structure, bone tissue morphology, bone metabolic biochemical markers and mechanical properties in tail-suspended female rats under simulated weightlessness, so as to provide certain theoretical support for the research on bone mass changes in female astronauts after the lfight and aerospace medicine.Methods Twenty 3-month-old female Sprague-Dawley ( SD ) rats were randomly divided into 2 groups. The tails of the rats in group A (n=10 ) were suspended for 4 weeks, and the other rates were taken as blank control group (n=10 ). All the rates were continuously fed for 4 weeks, and their general conditions were recorded, including activities, eating and drinking,defecation, weight, unhairing or not, death and tail falling off. All the rats were sacrificed at predetermined time points. The BMD of the L4 vertebral body and femoral condyle was evaluated by dual-energy X-ray absorption ( DEXA ). Micro computed tomography ( Micro-CT ) was applied to analyze the trabecular bone. Bone tissue slice staining was conducted by using ponceau. Serum bone metabolic biochemical markers were detected by Enzyme-linked immunosorbent assay ( ELISA ), and biochemical properties were investigated.Results At 4 weeks after the establishment of osteoporosis models, the activities, eating and drinking and defecation of the rats in group A were normal, and the differences in weight gain were not statistically significant between the 2 groups (P>0.05 ). No unhairing, death or tail falling off was noticed in either group. When compared with that in blank control group, the BMD of the L4 vertebral body and femoral condyle in group A was reduced by 29% and 30% (P<0.05 ). The bone volume / total volume ( BV/TV ), bone surface/bone volume ( BS/BV ), trabecular thickness ( Tb.Th ) and trabecular number ( Tb.N ) of the L4 vertebral body in group A was reduced by 40%, 15%, 30% and 33% when compared with

  3. Mechanisms of increase in cardiac output during acute weightlessness in humans

    DEFF Research Database (Denmark)

    Petersen, Lonnie G; Damgaard, Morten; Petersen, Johan Casper Grove;

    2011-01-01

    by parabolic flight increased CO by 1.7 ± 0.4 l/min (P ... in CO during acute 0 G in seated humans. A Bainbridge-like reflex could be the mechanism for the HR-induced increase in CO during 0 G in particular in supine subjects....

  4. Bone growth and calcium balance during simulated weightlessness in the rat

    Science.gov (United States)

    Roer, Robert D.; Dillaman, Richard M.

    1990-01-01

    Rats, age 28 days, experiencing tail suspension in modified metabolic cages for 1, 2, and 3 wk were compared with littermate controls. Food and water consumption, urinary and fecal Ca excretion, and serum Ca were measured; hearts, fore- and hindlimb bones, skulls, and mandibles were removed for determination of wet, dry, and ash weights and Ca concentration and for histological examination. Weight gain and Ca intake and excretion were the same for both groups; both displayed net Ca gain. Suspended rats had significantly lower wet, dry, and ash weights of femora and tibiae. Dry weights of the humeri and radii/ulnae were moderately higher, and the skull and mandible dry and ash weights were significantly higher in suspended than in control rats. Cortical thickness of the femur, but not humerus, was less in suspended rats. The data are consistent with the hypothesis that bone growth is influenced by the cardiovascular changes associated with tail suspension.

  5. Reversal of weightlessness-induced musculoskeletal losses with androgens: quantification by MRI.

    Science.gov (United States)

    Wimalawansa, S M; Chapa, M T; Wei, J N; Westlund, K N; Quast, M J; Wimalawansa, S J

    1999-06-01

    Microgravity causes rapid decrement in musculoskeletal mass is associated with a marked decrease in circulatory testosterone levels, as we reported in hindlimb-suspended (HLS) rats. In this model which simulates microgravity, we hypothesized that testosterone supplementation should prevent these losses, and we tested this in two studies. Muscle volumes and bone masses were quantitated by using magnetic resonance imaging (MRI) on day 12. In the first study, 12-wk-old Sprague-Dawley rats that were HLS for 12 days lost 28.5% of muscle volume (53.3 +/- 4.8 vs. 74.5 +/- 3.6 cm3 in the ground control rats; P < 0.001) and had a 5% decrease in bone mineral density (BMD) (P < 0.05). In the second study, 30 male 12-wk-old Wistar rats were HLS and were administered either a vehicle (control), testosterone, or nandrolone decanoate (ND). An additional 20 rats were used as ground controls, one-half of which received testosterone. HLS rats had a significant reduction in muscle volume (42.9 +/- 3.0 vs. 56 +/- 1.8 cm3 in ground control rats; P < 0.01). Both testosterone and ND treatments prevented this muscle loss (51.5 +/- 2 and 51.6 +/- 1.2 cm3, respectively; a 63% improvement; P < 0. 05). There were no statistical differences between the two active treatment groups nor with the ground controls. Similarly, there was an 85% improvement in BMD in the testosterone group (1.15 +/- 0.04 vs. 1.04 +/- 0.04 density units in vehicle controls; P < 0.05) and a 76% improvement in the ND group (1.13 +/- 0.07 density units), whereas ground control rats had a BMD of 1.17 +/- 0.03 density units. Because serum testosterone levels are markedly reduced in this model of simulated microgravity, androgen replacement seems to be a rational countermeasure to prevent microgravity-induced musculoskeletal losses.

  6. Changes of contractile responses due to simulated weightlessness in rat soleus muscle

    Science.gov (United States)

    Elkhammari, A.; Noireaud, J.; Léoty, C.

    1994-08-01

    Some contractile and electrophysiological properties of muscle fibers isolated from the slow-twitch soleus (SOL) and fast-twitch extensor digitorum longus (EDL) muscles of rats were compared with those measured in SOL muscles from suspended rats. In suspendede SOL (21 days of tail-suspension) membrane potential (Em), intracellular sodium activity (aiNa) and the slope of the relationship between Em and log [K]o were typical of fast-twitch muscles. The relation between the maximal amplitude of K-contractures vs Em was steeper for control SOL than for EDL and suspended SOL muscles. After suspension, in SOL muscles the contractile threshold and the inactivation curves for K-contractures were shifted to more positive Em. Repriming of K-contractures was unaffected by suspencion. The exposure of isolated fibers to perchlorate (ClO4-)-containing (6-40 mM) solutions resulted ina similar concentration-dependent shift to more negative Em of activation curves for EDL and suspended SOL muscles. On exposure to a Na-free TEA solution, SOL from control and suspended rats, in contrast to EDL muscles, generated slow contractile responses. Suspended SOL showed a reduced sensitivity to the contracture-producing effect of caffeine compared to control muscles. These results suggested that the modification observed due to suspension could be encounted by changes in the characteristics of muscle fibers from slow to fast-twitch type.

  7. Effects of simulated weightlessness on meiosis. Fertilization, and early development in mice

    Science.gov (United States)

    Wolgemuth, D. J.

    1986-01-01

    The initial goal was to construct a clinostat which could support mammalian cell culture. The clinostat was selected as a means by which to simulate microgravity conditions within the laboratory, by constant re-orientation of cells with respect to the gravity vector. The effects of this simulated microgravity on in-vitro meiotic maturation of oocytes, using mouse as the model system, was investigated. The effects of clinostat rotation on fertilization in-vitro was then examined. Specific endpoints included examining the timely appearance of male and female pronuclei (indicating fertilization) and the efficiency of extrusion of the second polar body. Particular attention was paid to detecting anomalies of fertilization, including parthenogenetic activation and multiple pronuclei. Finally, for the preliminary studies on mouse embryogenesis, a key feature of the clinostat was modified, that of the position of the cells during rotation. A means was found to immobilize the cells during the clinostat reotation, permitting the cells to remain at the axis of rotation yet not interfering with cellular development.

  8. Impact of weightlessness on cardiac shape and left ventricular stress/strain distributions.

    Science.gov (United States)

    Iskovitz, Ilana; Kassemi, Mohammad; Thomas, James D

    2013-12-01

    In this paper, a finite element model of the heart is developed to investigate the impact of different gravitational loadings of Earth, Mars, Moon, and microgravity on the cardiac shape and strain/stress distributions in the left ventricle. The finite element model is based on realistic 3D heart geometry, detailed fiber/sheet micro-architecture, and a validated orthotropic cardiac tissue model and constitutive relationship that capture the passive behavior of the heart at end-diastole. The model predicts the trend and magnitude of cardiac shape change at different gravitational levels with great fidelity in comparison to recent cardiac sphericity measurements performed during simulated reduced-gravity parabolic flight experiments. Moreover, the numerical predictions indicate that although the left ventricular strain distributions remain relatively unaltered across the gravitational fields and the strain extrema values occur at the same relative locations, their values change noticeably with decreasing gravity. As for the stress, however, both the magnitude and location of the extrema change with a decrease in the gravitational field. Consequently, tension regions of the heart on Earth can change into compression regions in space.

  9. Suspension restraint - Induced hypokinesia and antiorthostasis as a simulation of weightlessness

    Science.gov (United States)

    Musacchia, X. J.; Steffen, J. M.; Deavers, D. R.

    1982-01-01

    Muscle, renal, fluid and electrolyte responses were measured in suspended rats; the hind limbs are non-load bearing and the front limbs can be used for feeding and grooming. Hind limb hypokinesia reverses after removal from the suspension harness. This suspension system is adjustable for a head-down tilt to produce antiorthostatic responses which are also reversible. Responses to hypokinesia or antiorthostatic hypokinesia for up to 14 days were measured, e.g., muscle atrophy: soleus greater than gastrocnemius equals plantaris greater than extensor digitorum longus, kaliuresis, and increased excretion of urea, NH3, and 3 methylhistidine. Muscle protein loss, a response to a reduction in RNA, is also reversible. A head-down tilt for 7-14 days results in diuresis and natriuresis. These changes are reversed within 24 hours after removal from the restraint harness. Physiological effects of suspension restraint can be used to simulate and predict responses to microgravity exposure.

  10. Is suppression of bone formation during simulated weightlessness related to glucocorticoid levels

    Science.gov (United States)

    Morey-Holton, E. R.; Bomalaski, M. D.; Enayati-Gordon, E.; Gonsalves, M. R.; Wronski, T. J.

    1982-01-01

    To investigate the hypothesis that suppression of bone formation in the suspended rat model was the result of increased levels of corticosterone, experiments were performed on young, growing, male rats exposed either to 4 C or suspended for two weeks. Rats suspended on the model system, designed to simulate certain aspects of spaceflight, gained weight at a rate at least equal to control animals but still showed a significant suppression of bone formation within 7 days. Cold-exposed rats gained less weight than their corresponding control group and did not demonstrate any suppression of bone formation. These findings suggest: (1) tail suspension is less stressful than previously used harness systems; (2) suspension in young, rapidly growing rats causes a significant suppression of cortical bone formation; (3) cold exposure does not alter bone formation rate in rats of a similar age and strain to those suspended in this study; and (4) suppression of bone formation provoked by unloading the rear limbs is not due solely to sustained stimulation of the pituitary-adrenal system.

  11. Effect of strontium ranelate on the bone histomorphometry after weightlessness in rats

    OpenAIRE

    A-na LAI; Yang, Rui; Zhang, Zhen; Wang, Mei; Chen, Rong-Ping; Zhou, Ying; Huang, Zhen; Hong CHEN

    2011-01-01

    Objective To investigate the effect of strontium ranelate(SR) on the bone histomorphometry of tail-suspended rat.Methods Thirty male SD rats(3 months old) were randomly divided into five groups(6 each): rats in SR-1 group underwent tail suspension for 4 weeks and given SR simultaneously.In SR-2 group rats received tail suspension for 4 weeks and given SR thereafter.In SR-3 group rats underwent tail suspension for 4 weeks and given SR during the whole course.In control-1 group rats underwent t...

  12. The salutary effect of dietary calcium on bone mass in a rat model of simulated weightlessness

    Science.gov (United States)

    Bikle, D. D.; Globus, R.; Halloran, B. P.; Morey-Holton, E.

    1985-01-01

    Whether supplementation of dietary calcium reduces the differences in bone mass of unweighed limbs and normally weighted limbs, and whether parathyroid hormone (PTH) and 1,25-dihydroxyvitamin D (1,25(OH)2D) respond differently to dietary calcium in unweighted animals in comparison with pair-fed controls was studied. The hind limbs of rats were unweighted by a tail suspension method and diets containing 0.1% to 2.4% calcium. After 2 weeks serum calcium, phosphorus, PTH and 1,25(OH)2D intestinal calcium transport were determined and bone mass, ash weight, and calcium in the tibia, L-1 vertebra, and humerus were measured. No significant differences in body weights were observed among the various groups. Suspended rats maintained constant levels of serum calcium and phosphate over the wide range of dietary calcium. Serum PTH and 1,25(OH)2D and intestinal calcium transport fell as dietary calcium was increased. Bone calcium in the tibia and vertebra from suspended rats remained less than that from pair-fed control. It is suggested that although no striking difference between suspended and control animals was observed in response to dieteary calcium, increasing dietary calcium may reduce the negative impact of unloading on the calcium content of the unweighted bones. The salutary effect of high dietary calcium appears to be due to inhibition of bone resorption rather than to stimulation of bone formation.

  13. Effect of strontium ranelate on the bone histomorphometry after weightlessness in rats

    Directory of Open Access Journals (Sweden)

    A-na LAI

    2011-06-01

    Full Text Available Objective To investigate the effect of strontium ranelate(SR on the bone histomorphometry of tail-suspended rat.Methods Thirty male SD rats(3 months old were randomly divided into five groups(6 each: rats in SR-1 group underwent tail suspension for 4 weeks and given SR simultaneously.In SR-2 group rats received tail suspension for 4 weeks and given SR thereafter.In SR-3 group rats underwent tail suspension for 4 weeks and given SR during the whole course.In control-1 group rats underwent tail suspension for 4 weeks and not given SR,and in control-2 group rats did not undergo tail suspension and were not given SR.Animals were sacrificed 8 weeks(including 4 weeks of tail suspension later,and the cancellous bone of upper end of tibia was then analyzed histomorphologically.Results There were no significant differences between control-2 group and the 3 SR groups in static parameters [trabecular bone area(%Tb.Ar,trabecular thickness(Tb.Th,trabecular number(Th.N and trabecular separation(Tb.Sp] and dynamic parameters [labeled perimeter(%L.Pm,bone formation rate(BFR/TV,mineral apposition rate(MAR,and osteoclast number(Oc.N].On then other hand,Tb.Th,Th.N,%Tb.Ar,%L.Pm,BFR/TV and MAR increased,and Tb.Sp and Oc.N decreased in the 3 SR groups compared with those in control-1 group,implying that the bone mass was increased.No significant difference was found in all the parameters mentioned above between the 3 SR groups.Conclusions Strontium ranelate may obviously improve the bone histomorphometry of tail suspended rats,and have an effect on preventing osteoporosis caused by agravity.

  14. Review of the biological effects of weightlessness on the human endocrine system

    Science.gov (United States)

    Hughes-Fulford, M.

    1993-01-01

    Studies from space flights over the past two decades have demonstrated that there are basic physiological changes in humans during space flight. These changes include cephalad fluid shifts, loss of fluid and electrolytes, loss of muscle mass, space motion sickness, anemia, reduced immune response, and loss of calcium and mineralized bone. The cause of most of these manifestations is not known but the general approach has been to investigate systemic and hormonal changes. However, data from the 1973-1974 Skylabs, Spacelab 3 (SL-3), Spacelab D-I (SL-DI), and now the new SLS-1 missions support a more basic biological response to microgravity that may occur at the tissue, cellular, and molecular level. This report summarizes ground-based and SLS-1 experiments that examined the mechanism of loss of red blood cell mass in humans, the loss of bone mass and lowered osteoblast growth under space flight conditions, and loss of immune function in microgravity.

  15. Biochemical Assessment of Stress in Cardiac Tissue in Response to Weightless Space Travel

    Science.gov (United States)

    Brunton, Laurence L.; Meszaros, J. Gary; Lio, Francisco M.

    1997-01-01

    The absence of unit gravity may cause physiological changes in the cardiovascular system. For instance, in the absence of Earth's gravity, venous return to the heart may increase due, in pan, to decreased pooling of the blood in the extremities. We hypothesize that this would produce an increase in the heart's work load ultimately resulting in hypertrophy.

  16. Simulated weightlessness alters biological characteristics of human breast cancer cell line MCF-7

    Science.gov (United States)

    Qian, Airong; Zhang, Wei; Xie, Li; Weng, Yuanyuan; Yang, Pengfei; Wang, Zhe; Hu, Lifang; Xu, Huiyun; Tian, Zongcheng; Shang, Peng

    The aim of this study is to investigate the effects of the clinostat-simulated microgravity on MCF-7 cells (a breast cancer cell line) biological characteristics. MCF-7 cells were incubated for 24 h in an incubator and then rotated in a clinostat as a model of simulated microgravity for 24, 48 and 72 h, respectively. The effects of the clinostat-simulated microgravity on MCF-7 cells proliferation, invasion, migration, gelatinase production, adhesion, cell cycle, apoptosis and vinculin expression were detected. The results showed that the clinostat-simulated microgravity affected breast cancer cell invasion, migration, adhesion, cell cycle, cell apoptosis and vinculin expression. These results may explore a new field of vision to study tumor metastasis in future.

  17. Short-term weightlessness produced by parabolic flight maneuvers altered gene expression patterns in human endothelial cells

    NARCIS (Netherlands)

    Grosse, J.; Wehland, M.; Pietsch, J.; Ma, X.; Ulbrich, C.; Schulz, H.; Saar, K.; Hübner, N.; Hauslage, J.; Hemmersbach, R.; Braun, M.; van Loon, J.; Vagt, N.; Infanger, M.; Eilles, C.; Egli, M.; Richter, P.; Baltz, T.; Einspanier, R.; Sharbati, S.; Grimm, D.

    2012-01-01

    This study focused on the effects of short-term microgravity (22 s) on the gene expression and morphology of endothelial cells (ECs) and evaluated gravisensitive signaling elements. ECs were investigated during four German Space Agency (Deutsches Zentrum für Luft- und Raumfahrt) parabolic flight cam

  18. Studies of acid-base homeostasis during simulated weightlessness: Application of the water immersion model to man

    Science.gov (United States)

    Epstein, M.

    1975-01-01

    The effects of water immersion on acid-base homeostasis were investigated under carefully controlled conditions. Studies of renal acidification were carried out on seven healthy male subjects, each consuming a diet containing 150 meq sodium and 100 meq potassium. Control and immersion studies were carried out on each subject on the fourth and sixth days, respectively, of dietary equilibration, by which time all subjects had achieved sodium balance. The experimental protocols on study days were similar (except for the amount of water administered).

  19. Short-term weightlessness produced by parabolic flight maneuvers altered gene expression patterns in human endothelial cells

    NARCIS (Netherlands)

    Grosse, J.; Wehland, M.; Pietsch, J.; Ma, X.; Ulbrich, C.; Schulz, H.; Saar, K.; Hübner, N.; Hauslage, J.; Hemmersbach, R.; Braun, M.; van Loon, J.; Vagt, N.; Infanger, M.; Eilles, C.; Egli, M.; Richter, P.; Baltz, T.; Einspanier, R.; Sharbati, S.; Grimm, D.

    2012-01-01

    This study focused on the effects of short-term microgravity (22 s) on the gene expression and morphology of endothelial cells (ECs) and evaluated gravisensitive signaling elements. ECs were investigated during four German Space Agency (Deutsches Zentrum für Luft- und Raumfahrt) parabolic flight cam

  20. Role of digitalis-like substance in the hypertension of streptozotocin-induced diabetes and simulated weightlessness in rats

    Science.gov (United States)

    Pamnani, M. B.; Chen, S.; Haddy, F. J.; Yuan, C.; Mo, Z.

    1998-01-01

    We have examined the role of plasma Na+-K+ pump inhibitor (SPI) in the hypertension of streptozotocin induced insulin dependent diabetes (IDDM) in reduced renal mass rats. The increase in blood pressure (BP) was associated with an increase in extracellular fluid volume (ECFV), and SPI and a decrease in myocardial Na+,K+ATPase (NKA) activity, suggesting that increased SPI, which inhibits cardiovascular muscle (CVM) cell NKA activity, may be involved in the mechanism of IDDM-hypertension. In a second study, using prolonged suspension resulted in a decrease in cardiac NKA activity, suggesting that cardiovascular deconditioning following space flight might in part result from insufficient SPI.

  1. Acceleration Tolerance: Effect of Exercise, Acceleration Training; Bed Rest and Weightlessness Deconditioning. A Compendium of Research (1950-1996)

    Science.gov (United States)

    Chou, J. L.; McKenzie, M. A.; Stad, N. J.; Barnes, P. R.; Jackson, C. G. R.; Ghiasvand, F.; Greenleaf, J. E.

    1997-01-01

    This compendium includes abstracts and annotations of clinical observations and of more basic studies involving physiological mechanisms concerning interaction of acceleration, training and deconditioning. If the author's abstract or summary was appropriate, it was included. In other cases a more detailed annotation of the paper was prepared under the subheadings Purpose, Methods, Results, and Conclusions. Author and keyword indices are provided, plus an additional selected bibliography of related work and of those papers received after the volume was prepared for publication. This volume includes material published from 1950-1996.

  2. [Comparative evaluation of the circulatory reaction during work in weightlessness and in the mockup of the Saliut station].

    Science.gov (United States)

    Doroshev, V G; Lapshina, N A; Kirillova, Z A; Kulikov, O B; Kaliberdin, A V

    1982-01-01

    Comparative evaluations of circulation responses of 22 operators and 13 cosmonauts to simulated and real flights onboard Salyut station revealed significant differences. By the end of flight cardiovascular responses of the operators showed signs of their increased conditioning, whereas the cosmonauts exhibited symptoms of circulation tension, which were particularly expressed during the first week and by the end of flight. Operators' activities in an orbital station mockup cannot be considered an adequate model for cardiovascular studies.

  3. [Effect of weightlessness on the course of the reparative process in the muscles of the biosatellite Kosmos-2044 rats].

    Science.gov (United States)

    Il'ina-Kakueva, E I; Burkovskaia, T E

    1991-01-01

    The repair process in the soleus and gastrocnemius muscles of SPF Wistar rats flown for 14 days on the biosatellite Cosmos-2044 was investigated. The muscles were injured 2 days before launch by means of clamp forceps. The exposure inhibited the process but did not impair its phasic development. As a result, the reparative field diminished and took the size of an atrophic muscle; thinner myofibers appeared that originated from the ends of injured atrophic fibers and fibers that underwent splitting. It is postulated that repair inhibition is caused by the same mechanisms that produce muscle atrophy in microgravity. It is suggested that both repair inhibition and muscle atrophy are induced by disorders in the neurotrophic regulation of metabolism due to partial disuse.

  4. Studies of acid-base homeostasis during simulated weightlessness: Application of the water immersion model to man

    Science.gov (United States)

    Epstein, M.

    1975-01-01

    The effects of water immersion on acid-base homeostasis were investigated under carefully controlled conditions. Studies of renal acidification were carried out on seven healthy male subjects, each consuming a diet containing 150 meq sodium and 100 meq potassium. Control and immersion studies were carried out on each subject on the fourth and sixth days, respectively, of dietary equilibration, by which time all subjects had achieved sodium balance. The experimental protocols on study days were similar (except for the amount of water administered).

  5. Short-term weightlessness produced by parabolic flight maneuvers altered gene expression patterns in human endothelial cells.

    Science.gov (United States)

    Grosse, Jirka; Wehland, Markus; Pietsch, Jessica; Ma, Xiao; Ulbrich, Claudia; Schulz, Herbert; Saar, Katrin; Hübner, Norbert; Hauslage, Jens; Hemmersbach, Ruth; Braun, Markus; van Loon, Jack; Vagt, Nicole; Infanger, Manfred; Eilles, Christoph; Egli, Marcel; Richter, Peter; Baltz, Theo; Einspanier, Ralf; Sharbati, Soroush; Grimm, Daniela

    2012-02-01

    This study focused on the effects of short-term microgravity (22 s) on the gene expression and morphology of endothelial cells (ECs) and evaluated gravisensitive signaling elements. ECs were investigated during four German Space Agency (Deutsches Zentrum für Luft- und Raumfahrt) parabolic flight campaigns. Hoechst 33342 and acridine orange/ethidium bromide staining showed no signs of cell death in ECs after 31 parabolas (P31). Gene array analysis revealed 320 significantly regulated genes after the first parabola (P1) and P31. COL4A5, COL8A1, ITGA6, ITGA10, and ITGB3 mRNAs were down-regulated after P1. EDN1 and TNFRSF12A mRNAs were up-regulated. ADAM19, CARD8, CD40, GSN, PRKCA (all down-regulated after P1), and PRKAA1 (AMPKα1) mRNAs (up-regulated) provide a very early protective mechanism of cell survival induced by 22 s microgravity. The ABL2 gene was significantly up-regulated after P1 and P31, TUBB was slightly induced, but ACTA2 and VIM mRNAs were not changed. β-Tubulin immunofluorescence revealed a cytoplasmic rearrangement. Vibration had no effect. Hypergravity reduced CARD8, NOS3, VASH1, SERPINH1 (all P1), CAV2, ADAM19, TNFRSF12A, CD40, and ITGA6 (P31) mRNAs. These data suggest that microgravity alters the gene expression patterns and the cytoskeleton of ECs very early. Several gravisensitive signaling elements, such as AMPKα1 and integrins, are involved in the reaction of ECs to altered gravity.

  6. Short-term weightlessness produced by parabolic flight maneuvers altered gene expression patterns in human endothelial cells

    NARCIS (Netherlands)

    Grosse, J.; Wehland, M.; Pietsch, J.; Ma, X.; Ulbrich, C.; Schulz, H.; Saar, K.; Hübner, N.; Hauslage, J.; Hemmersbach, R.; Braun, M.; van Loon, J.; Vagt, N.; Infanger, M.; Eilles, C.; Egli, M.; Richter, P.; Baltz, T.; Einspanier, R.; Sharbati, S.; Grimm, D.

    2012-01-01

    This study focused on the effects of short-term microgravity (22 s) on the gene expression and morphology of endothelial cells (ECs) and evaluated gravisensitive signaling elements. ECs were investigated during four German Space Agency (Deutsches Zentrum für Luft- und Raumfahrt) parabolic flight

  7. Variation in stem morphology and movement of amyloplasts in white spruce grown in the weightless environment of the International Space Station.

    Science.gov (United States)

    Rioux, Danny; Lagacé, Marie; Cohen, Luchino Y; Beaulieu, Jean

    2015-01-01

    One-year-old white spruce (Picea glauca) seedlings were studied in microgravity conditions in the International Space Station (ISS) and compared with seedlings grown on Earth. Leaf growth was clearly stimulated in space whereas data suggest a similar trend for the shoots. Needles on the current shoots of ground-based seedlings were more inclined towards the stem base than those of seedlings grown in the ISS. Amyloplasts sedimented in specialized cells of shoots and roots in seedlings grown on Earth while they were distributed at random in similar cells of seedlings tested in the ISS. In shoots, such amyloplasts were found in starch sheath cells located between leaf traces and cortical cells whereas in roots they were constituents of columella cells of the cap. Nuclei were regularly observed just above the sedimented amyloplasts in both organs. It was also frequent to detect vacuoles with phenolic compounds and endoplasmic reticulum (ER) close to the sedimented amyloplasts. The ER was mainly observed just under these amyloplasts. Thus, when amyloplasts sediment, the pressure exerted on the ER, the organelle that can for instance secrete proteins destined for the plasma membrane, might influence their functioning and play a role in signaling pathways involved in gravity-sensing white spruce cells.

  8. Variation in stem morphology and movement of amyloplasts in white spruce grown in the weightless environment of the International Space Station

    Science.gov (United States)

    Rioux, Danny; Lagacé, Marie; Cohen, Luchino Y.; Beaulieu, Jean

    2015-01-01

    One-year-old white spruce (Picea glauca) seedlings were studied in microgravity conditions in the International Space Station (ISS) and compared with seedlings grown on Earth. Leaf growth was clearly stimulated in space whereas data suggest a similar trend for the shoots. Needles on the current shoots of ground-based seedlings were more inclined towards the stem base than those of seedlings grown in the ISS. Amyloplasts sedimented in specialized cells of shoots and roots in seedlings grown on Earth while they were distributed at random in similar cells of seedlings tested in the ISS. In shoots, such amyloplasts were found in starch sheath cells located between leaf traces and cortical cells whereas in roots they were constituents of columella cells of the cap. Nuclei were regularly observed just above the sedimented amyloplasts in both organs. It was also frequent to detect vacuoles with phenolic compounds and endoplasmic reticulum (ER) close to the sedimented amyloplasts. The ER was mainly observed just under these amyloplasts. Thus, when amyloplasts sediment, the pressure exerted on the ER, the organelle that can for instance secrete proteins destined for the plasma membrane, might influence their functioning and play a role in signaling pathways involved in gravity-sensing white spruce cells.

  9. Self-excited oscillation of droplets on confined substrate with instantaneous weightlessness%限位液滴瞬时失重自激振荡∗

    Institute of Scientific and Technical Information of China (English)

    石峰; 李伟斌; 李景庆; 蓝鼎; 王育人

    2015-01-01

    In order to further explore the oscillation mechanism of constrained droplets in microgravity and extend the applica-tion and management of space fluid, the small-amplitude self-excited oscillation processes of droplets that are pinned on a confined substrate are investigated. The substrate has a 5 mm diameter contact circle, which is implemented through the use of a drop tower and high-speed photography technology. Oscillation is a recovery procedure for droplet configuration in microgravity with the confined effect at the boundary, making the contact line and diameter unchanged throughout the entire process. A self-excited oscillation could be divided into two stages: a morphological change process and a small-amplitude damping attenuation oscillation. The first stage is a morphological change process, where the heights of high and low oscillations rise gradually, which in turn correspond to the variation of gravity. And the deformation rate is inversely proportional to the droplet size. The second stage is the small-amplitude damping attenuation oscillation around the equilibrium position until it reaches the final steady state in microgravity. At this stage, the frequency is nearly constant and the attenuation of amplitude represents an exponential damping, like the free oscillation of isolated viscous droplets. The pinning contact line makes the oscillation waveform deviate from sine curve and in the process there exists a period when the heights keep constant at some positions, such as the highest, lowest and others. Studies confirm the hypothesis that the oscillation occurs with the similar second-order mode of free drop when the height fluctuates, and the third-order mode when the height is immobile. This is in agreement with the spectral analysis. Furthermore, when the liquid volume varies within this experimental system, the pinning constraint with fixed contact area on the confined substrate can generate droplets with various static contact angles and undisturbed radii. The deformation stage and oscillation mode of the droplets remains stable, although the concrete courses differ in some ways. In the case of bigger drops, the phenomenon of height unchanging should be in the middle position and vanishes with time. However, the smaller one shows no signs for this condition, and the waveform remains consistent all around. In the second stage, the amplitude decay damping rate and non-dimensional frequency of small droplet are higher.

  10. More Life-Science Experiments For Spacelab

    Science.gov (United States)

    Savage, P. D., Jr.; Dalton, B.; Hogan, R.; Leon, H.

    1991-01-01

    Report describes experiments done as part of Spacelab Life Sciences 2 mission (SLS-2). Research planned on cardiovascular, vestibular, metabolic, and thermal responses of animals in weightlessness. Expected to shed light on effects of prolonged weightlessness on humans.

  11. More Life-Science Experiments For Spacelab

    Science.gov (United States)

    Savage, P. D., Jr.; Dalton, B.; Hogan, R.; Leon, H.

    1991-01-01

    Report describes experiments done as part of Spacelab Life Sciences 2 mission (SLS-2). Research planned on cardiovascular, vestibular, metabolic, and thermal responses of animals in weightlessness. Expected to shed light on effects of prolonged weightlessness on humans.

  12. Recurrence Quantification Analysis of Blood Pressure Signal in Rats after Simulated Weightlessness%模拟失重后大鼠血压信号的递归定量分析

    Institute of Scientific and Technical Information of China (English)

    刘欣; 程九华; 卢虹冰; 张立藩; 马进; 董秀珍

    2006-01-01

    目的 应用递归图示法和递归定量法分析清醒大鼠的血压信号,评价可否检测出模拟失重所引起的心血管调节改变.方法 以尾部悬吊大鼠模型模拟失重对心血管调节功能的影响,另设同步对照动物进行比较.14 d后,通过慢性植入的PE-50-PE-10聚乙烯导管连续记录清醒状态下两组大鼠的血压数据.数据处理使用递归图示法(recurrence plot analysis, RPA)对大鼠收缩压变异性(systolic blood pressure variability, SBPV)信号的非线性特征进行定性分析;随后使用递归定量分析(recurrence quantification analysis, RQA)计算递归百分数(%REC)、确定线段百分数(%DET)和Lmax指数3个特征指标值,对其进行量化处理.结果 与对照组相比,悬吊组大鼠血压的3个非线性指数均显著降低(P<0.05或0.01),表明血压波动趋于更加混沌的状态.对照组的%REC、%DET与Lmax指数分别为90.28±1.21、99.24±0.16与84.57±2.28,而模拟失重组则为74.89±2.13、93.61±2.82与57.71±2.14. 结论 RPA与RQA是动脉血压信号处理的一种新的方法,可以检测出14 d模拟失重所引起的清醒大鼠心血管调节变化,在心血管信号分析领域中有一定应用前景.

  13. Effect of strontium ranelate on the bone histomorphometry after weightlessness in rats%雷尼酸锶对尾悬吊大鼠骨组织形态计量学的影响

    Institute of Scientific and Technical Information of China (English)

    赖阿娜; 杨锐; 张振; 王梅; 陈容平; 周瑛; 黄震; 陈宏

    2011-01-01

    目的 观察雷尼酸锶(SR)对尾悬吊大鼠骨组织形态计量学的影响.方法 选用30只3月龄SPF级雄性SD大鼠,随机分为全程对照组(n=6)、尾悬吊时服用SR组(n=6)、尾悬吊后服用SR组(n=6)、全程服用SR组(n=6)和尾悬吊后对照组(n=6).8周(其中尾悬吊4周)后处死,取胫骨上端松质骨进行骨组织形态计量学观察.结果 与全程对照组比较,SR干预组静态参数[骨小梁面积百分数(%Tb.Ar)、骨小梁厚度(Tb.Th)、骨小粱数目(Th.N)、骨小梁分离度(Tb.Sp)]、骨形成参数[荧光标记周长百分率(%L.Pm)、单位骨小梁面积骨形成率(BFR/TV)、矿化沉积率(MAR)]及骨吸收参数单位骨小梁面积上的成骨细胞数(Oc.N)均无统计学差异.与尾悬吊后对照组比较,SR干预组Tb.Th、Th.N、%Tb.Ar增加,Tb.Sp减少,提示骨量增加,%L.Pm、BFR/TV、MAR等骨形成参数增加,骨吸收参数Oc.N降低,而SR干预各组间静态参数、骨形成参数及骨吸收参数均无统计学差异.结论 SR可明显改善尾悬吊大鼠骨组织形态计量学指标,对失重性骨质疏松有防治作用.%Objective To investigate the effect of strontium ranelate (SR) on the bone histomorphometry of tail-suspended rat.Methods Thirty male SD rats (3 months old) were randomly divided into five groups (6 each): rats in SR-1 group underwent tail suspension for 4 weeks and given SR simultaneously. In SR-2 group rats received tail suspension for 4 weeks and given SR thereafter. In SR-3 group rats underwent tail suspension for 4 weeks and given SR during the whole course. In control-1 group rats underwent tail suspension for 4 weeks and not given SR, and in control-2 group rats did not undergo tail suspension and were not given SR. Animals were sacrificed 8 weeks (including 4 weeks of tail suspension) later, and the cancellous bone of upper end of tibia was then analyzed histomorphologically. Results There were no significant differences between control-2 group and the 3 SR groups in static parameters [trabecular bone area ( %Tb. Ar) , trabecular thickness (Tb. Th) , trabecular number (Th. N) and trabecular separation (Tb. Sp)] and dynamic parameters [labeled perimeter ( % L. Pm) , bone formation rate (BFR/TV) , mineral apposition rate (MAR), and osteoclast number (Oc. N)]. On then other hand, Tb. Th, Th. N, %Tb. Ar, %L. Pm, BFR/TV and MAR increased, and Tb. Sp and Oc. N decreased in the 3 SR groups compared with those in control-1 group, implying that the bone mass was increased. No significant difference was found in all the parameters mentioned above between the 3 SR groups. Conclusions Strontium ranelate may obviously improve the bone histomorphometry of tail suspended rats, and have an effect on preventing osteoporosis caused by agravity.

  14. 模拟失重对猕猴脊髓c-fos基因表达的影响%Effects of Simulated Weightlessness on c-fos Gene Expression in Spinal Cord of Rhesus Monkey

    Institute of Scientific and Technical Information of China (English)

    石红琴; 蔡艺灵; 马华松; 刘丽; 李晶晶; 张晓蕴; 陈志明; 郑燕华

    2016-01-01

    目的 探讨猕猴模拟失重后脊髓中c-fos基因mRNA和蛋白表达的变化.方法 选用15只雄性猕猴,随机分为3组:模拟失重组,模拟失重后恢复组以及对照组.通过HE染色法观察脊髓颈膨大及腰膨大组织学的改变,通过免疫组织化学染色及实时荧光定量PCR (Q-PCR)技术检测3组猕猴脊髓颈膨大及腰膨大中c-fos基因的表达情况.结果 模拟失重组及失重后恢复组脊髓颈膨大及腰膨大神经元较对照组皱缩,组织间隙增宽,恢复组较失重组有所减轻;FOS蛋白在脊髓颈膨大及腰膨大3组中均呈阳性表达,主要表达于神经胶质细胞;失重组及恢复组中脊髓颈膨大和腰膨大c-fos mRNA表达量较对照组有所增加,但差异无明显统计学意义.结论 模拟失重引起猕猴颈段及腰段脊髓一定程度的组织学损伤,终止负荷后有所恢复,对c-fos基因的表达无明显影响.

  15. Monitoring Microbes in the Spacecraft Environment by Mass Spectrometry of Ribosomal RNA Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The unique stresses in the spacecraft environment including isolation, containment, weightlessness, increased radiation exposure, and enhanced microbial...

  16. Space Gerontology

    Science.gov (United States)

    Miquel, J. (Editor); Economos, A. C. (Editor)

    1982-01-01

    Presentations are given which address the effects of space flght on the older person, the parallels between the physiological responses to weightlessness and the aging process, and experimental possibilities afforded by the weightless environment to fundamental research in gerontology and geriatrics.

  17. The paradox of systemic vasodilatation and sympathetic nervous stimulation in space

    DEFF Research Database (Denmark)

    Norsk, Peter; Christensen, Niels Juel

    2009-01-01

    decreased by 5mmHg. This is in accordance with observations that very acute weightlessness during parabolic airplane flights and a week of weightlessness in space leads to a decrease in systemic vascular resistance. That the arterial resistance vessels are dilated in space is in contrast to the augmented...

  18. Vasorelaxation in space

    DEFF Research Database (Denmark)

    Norsk, Peter; Damgaard, Morten; Petersen, Lonnie Grove

    2005-01-01

    leads to a prompt increase in cardiac output and to systemic vasodilatation and that these effects persist for at least a week of weightlessness in space. Cardiac output and mean arterial pressure were measured in 8 healthy humans during acute 20-s periods of weightlessness in parabolic airplane flights...

  19. Physiological responses to environmental factors related to space flight

    Science.gov (United States)

    Pace, N.; Grunbaum, B. W.; Kodama, A. M.; Mains, R. C.; Rahlmann, D. F.

    1975-01-01

    Physiological procedures and instrumentation developed for the measurement of hemodynamic and metabolic parameters during prolonged periods of weightlessness are described along with the physiological response of monkeys to weightlessness. Specific areas examined include: cardiovascular studies; thyroid function; blood oxygen transport; growth and reproduction; excreta analysis for metabolic balance studies; and electrophoretic separation of creatine phosphokinase isoenzymes in human blood.

  20. [Plasma and tissue lipids in rats after a flight on the Kosmos-936 biosatellite].

    Science.gov (United States)

    Ahlers, J; Tigranian, R A; Praslická, M

    1982-01-01

    The content of triglycerides, total cholesterol, phospholipids and nonesterified fatty acids was measured in plasma and tissues of rats flown for 18.5 days on Cosmos-936 in the weightless and centrifuged state. The weightlessness exposure increased lipid fractions in plasma and tissues, and artificial gravity produced a beneficial effect.

  1. [The righting reaction in the free fall of rats after a flight on the Kosmos-936 biosatellite].

    Science.gov (United States)

    Aĭzikov, G S; Markin, A S; Shipov, A A

    1992-01-01

    The free fall turning over reaction has been studied in the weightless and centrifuged rats flown on board Cosmos 936. There occur particular changes of the reaction in the weightless rats after landing and its complete absence in eyes-closed centrifuged rats. The possible mechanisms responsible for the observed alterations are discussed.

  2. Human homeostasis in the space environment: A systems synthesis approach

    Science.gov (United States)

    Economos, A. C.

    1982-01-01

    The features of homeostatic changes which occur during adaptation to the weightless state are examined and the possible mechanisms underlying the responses are explored. Cardiac output, negative fluid balance, body weight, bone calcium, and muscle atrophy are discussed. Some testable hypotheses concerning possible effects on homeostasis that long-term exposure to weightlessness might cause are proposed.

  3. Aerospace gerontology

    Science.gov (United States)

    Comfort, A.

    1982-01-01

    The relevancy of gerontology and geriatrics to the discipline of aerospace medicine is examined. It is noted that since the shuttle program gives the facility to fly passengers, including specially qualified older persons, it is essential to examine response to acceleration, weightlessness, and re-entry over the whole adult lifespan, not only its second quartile. The physiological responses of the older person to weightlessness and the return to Earth gravity are reviewed. The importance of the use of the weightless environment to solve critical problems in the fields of fundamental gerontology and geriatrics is also stressed.

  4. KC-135 Operations Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The KC-135 Low-G Flight Research aircraft (a predecessor of the Boeing 707) is used to fly parabolas to create 20-25 seconds of weightlessness so that the astronauts...

  5. Quantitative aspects of oxygen and carbon dioxide exchange ...

    African Journals Online (AJOL)

    Quantitative aspects of oxygen and carbon dioxide exchange through the lungs in ... and O2 exchange rates using the method of instantaneous measurements of ... density of 1.044, float nearly weightless with a minimum of body movements.

  6. Future investigations onboard Soviet biosatellites of the Cosmos series.

    Science.gov (United States)

    Ilyin, E A

    1981-01-01

    Many rat experiments onboard Cosmos biosatellites have furnished information concerning the effects of weightlessness, artificial gravity, and ionizing radiation combined with weightlessness on structural and biochemical parameters of the animal body. The necessity to expand the scope of physiological investigations has led to the project of flight primate studies. It is planned to carry out the first primate experiments onboard the Cosmos biosatellite in 1982. At present investigations of weightlessness effects on the cardiovascular and vestibular systems, higher nervous activity, skeletal muscles and biorhythms of two rhesus monkeys are being developed and tested. It is also planned to conduct a study of weightlessness effects on embryogenesis of rats and bioenergetics of living systems onboard the same biosatellite. Further experiments onboard Cosmos biosatellites are planned.

  7. Foundations of space biology and medicine. Volume 2, book 1: Ecological and physiological bases of space biology and medicine

    Science.gov (United States)

    Calvin, M. (Editor); Gazenko, O. G. (Editor)

    1975-01-01

    Barometric pressure, gas composition, toxicity, and thermal exchange of spacecraft cabin atmospheres are discussed. Effects of gravitation, acceleration, weightlessness, noise, and vibration on human behavior and performance during space flight are also described.

  8. Effect of spaceflight on the maximal shortening velocity, morphology, and enzyme profile of fast- and slow-twitch skeletal muscle fibers in rhesus monkeys

    Science.gov (United States)

    Fitts, R. H.; Romatowski, J. G.; De La Cruz, L.; Widrick, J. J.; Desplanches, D.

    2000-01-01

    Weightlessness has been shown to cause limb muscle wasting and a reduced peak force and power in the antigravity soleus muscle. Despite a reduced peak power, Caiozzo et al. observed an increased maximal shortening velocity in the rat soleus muscle following a 14-day space flight. The major purpose of the present investigation was to determine if weightlessness induced an elevated velocity in the antigravity slow type I fibers of the rhesus monkey (Macaca mulatta), as well as to establish a cellular mechanism for the effect. Spaceflight or models of weightlessness have been shown to increase glucose uptake, elevate muscle glycogen content, and increase fatigability of the soleus muscle. The latter appears to be in part caused by a reduced ability of the slow oxidative fibers to oxidize fats. A second goal of this study was to establish the extent to which weightlessness altered the substrate profile and glycolytic and oxidative enzyme capacity of individual slow- and fast-twitch fibers.

  9. KC-135 Operations Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The KC-135 Low-G Flight Research aircraft (a predecessor of the Boeing 707) is used to fly parabolas to create 20-25 seconds of weightlessness so that the astronauts...

  10. Astronaut Judith Resnik participates in WETF training

    Science.gov (United States)

    1984-01-01

    Astronaut Judith Resnik participates in extravehicular activity (EVA) training in the Weightless Environment Training Facility (WETF). She is wearing an extravehicular mobility unit (EMU) and is being assisted to don her gloves.

  11. Understanding metabolic alterations in space flight using quantitative models: fluid and energy balance

    Science.gov (United States)

    Leonard, J. I.

    1986-01-01

    This report summarizes many of the results obtained during the Skylab program, on metabolic changes during weightlessness. The examination of the data was conducted following an integrated multi-disciplinary and multi-experimental approach. Emphasis is given on several major aspects of metabolic adaptation to space flight: fluid-electrolyte regulation, mechanisms of hormone disturbances, energy balance and etiology of weight loss. The aim is to obtain a composite picture of the fluid, electrolyte and energy response to weightlessness.

  12. Understanding metabolic alterations in space flight using quantitative models. Fluid and energy balance

    Science.gov (United States)

    Leonard, Joel I.

    This report summarizes many of the results obtained during the Skylab program, on metabolic changes during weightlessness. The examination of the data was conducted following an integrated multi-disciplinary and multi-experimental approach. Emphasis is given on several major aspects of metabolic adaptation to space flight: fluid-electrolyte regulation, mechanisms of hormone disturbances, energy balance and etiology of weight loss. The aim is to obtain a composite picture of the fluid, electrolyte and energy response to weightlessness.

  13. [Research on the Kosmos biosatellites].

    Science.gov (United States)

    Il'in, E A

    1984-01-01

    In the last decade the USSR has launched six biosatellites of the Cosmos series. The duration of the first flight was 6 days and of the five subsequent flights 18 to 21 days. The major goals of the flight studies were: investigation of adaptation of living systems to weightlessness, identification of the modifying effect of weightlessness on radiosensitivity, and detection of the biological effect of artificial gravity. The examinations were performed on 37 biological species, with most of them on rats. The exposure to weightlessness gave rise to moderate stress reactions and specific changes, particularly in the musculo-skeletal system (muscle atrophy, reduced bone strength, etc). Artificial gravity of 1 g generated inflight helped maintain the normal function of most physiological systems. The exposure of mammals (rats) to 137Ce irradiation did not reveal a modifying effect of weightlessness on radiation sickness. Distinct manifestations of the effects of weightlessness on intracellular processes were not observed. Dissimilar results were obtained with respect to the growth and development of living organisms in weightlessness.

  14. [Experiments with cultures of mammalian cells aboard the biosatellite "Cosmos-782"].

    Science.gov (United States)

    Sushkov, F V; Rudneva, S V; Nadtocheĭ, G A; Polikarpova, S I; Portugalov, V V

    1977-10-01

    A considerable contribution to the investigation on biological importance of weightlessness was made by the experiments with animals in the artificial Earth satelites (AES) of "Cosmos" type. Cell cultures can serve as an ideal model to get a direct cell response to the effect of external factors. For the experiment in the AES "Cosmos-782", two thoroughly examined cell strains (L and 237) were chosen, which differed in a number of parameters (for example, duration of their mitotic cycles). Density of cell seeding and temperature of their cultivation in the laboratory experiment were calculated in such a way that the whole cycle of the culture development should take place under the conditions of weightlessness: the beginning of lag-phase--before launching and the stationary phase--after landing. The weightlessness was not shown to result in any genetical shifts revealed at chromosomal level. When cultivated after the flight, the cells do not change their mitotic cycle parameters, mitotic course and structural organization. The data obtained in the experiments with AES "Cosmos-368" and "Cosmos-782" (increase of mitotic index, some forms of mitotic pathology during the first terms of cultivation after the flight and enlargement of cellular nuclei) demonstrate the changes in the cell population which have formed under the conditions of weightlessness. Similar changes are observed while the cells propagate in the laboratory conditions. Indirect data on an earlier cell culture aging during the flight do not exclued the possibility that under weightlessness the rate of cell propagation could differ from that under gravitation.

  15. [Effects of space-flight factors on cytochemical characteristics of the motor analyzer neurons].

    Science.gov (United States)

    Gorbunova, A V

    2010-01-01

    The work was designed to study metabolism of motoneurons in anterior horns of the spinal cord and sensorimotor cortex of Wistar rats after flights on Earth's satellites for 22.5 days (Kosmos-605), 19.5 days (Kosmos-782), and 18.5 days (Kosmos-936). Control rats underwent simulated space-flight factors under laboratory conditions excepting weightlessness. Rats placed in Kosmos-936 were subjected to artificial gravity (AG). They showed complete recovery of motoneuronal metabolism 25 days after landing unlike animals that had experienced weightlessness in which enhanced functional activity of the genetic apparatus was manifest as increased RNA level, protein content, and nuclei size. These finding may reflect differences of neuronal metabolism in animals experiencing weightlessness and AG. We believe they may be due to reduced static load on the locomotor system during the space flight.

  16. Orpheus 0 G or ear In microgravity to establish symptoms concomitant of inner and middle ear and osteoporosis in microgravity

    Science.gov (United States)

    Tomatis, Alfred; Talbi, Louisa; Vervoort, Jozef; Fromenteau, Joel; De Voigt, Martin; Van Deun, Jozef

    2005-08-01

    The goal of the proposed work is to collect data on the responses of the vestibular system to long-term conditions of weightlessness and to evaluate the benefits of a program of Electronic Ear(1) designed to act preventively to lessen symptoms due to weightlessness and to readapt the vestibular system after return to normal gravity.Data in the form of listening tests and brain maps tests(2) and observations(3) will be collected during pre- and post-flight simulation.We have to identify if the preservation process of astronauts against weightlessness effects is located in the ear. The long- term objective of the study is to create a blueprint of an Electronic Ear to be used on board should the outcome be positive.

  17. Bone loss in tail-suspended rats in restricted to the unweighted limbs

    Science.gov (United States)

    Bikle, D. D.; Globus, R.; Morey-Holton, E. R.

    1984-01-01

    Space flight which results in certain characteristic changes in the skeleton and it was hypothesized that these abnormalities are a direct result of the weightless state. To determine the role of PTH and 1,25(OH)2D in the bone changes associated with weightlessness, we studied bone metabolism under various dietary conditions using an Earth based rat model system which simulates weightlessness. In this model, rats are suspended by their tails such that their rear limbs are completely unloaded while their fore limbs are normally loaded. It is suggested that skeletal unloading induces a localized defect in the unloaded bone which results in abnormal growth and mineralization. It is concluded that skeletal unloading may make the unloaded bone more or less sensitive to a systemic factor which in turn could account for a change in bone metabolism.

  18. Increased hematuria following hypergravic exposure in middle-aged women

    Science.gov (United States)

    Goldwater, D. J.; Ohara, D. B.; Sandler, H.

    1982-01-01

    The effects of simulated weightlessness on orthostatic tolerance were studied in 9 women (55 to 65 years old) who underwent acceleration and lower body negative pressure before and after 10 days of horizontal bed rest. The results of this study show the first known association of microscopic hematuria with hypergravic and orthostatic stress which suggests similarities to the 'stress hematuria syndrome' previously seen with heavy exercise (Boileau et al., 1980). In addition, the sporadic occurrence of this phenomenon indicates a multifactorial etiology in predisposed individuals. Bedrest or weightlessness simulation per se does not seem to significantly alter renal function, but may decrease microscopic hematuria with an orthostatic component.

  19. Skylab II - Seeing the sun in a different light. [mission equipment, experiments and observations

    Science.gov (United States)

    Green, W. D.

    1974-01-01

    The second Skylab mission continued the detailed investigation of man's interrelated physiological functions as they react to the novel situation of weightlessness in orbit. In general terms, the most important finding is that the increase in mission duration from 28 to 59 days failed to reveal any effects that would put a specific upper limit on the time that men can live in weightlessness. Observations of the sun during the second mission covered almost two full solar revolutions, yielding detailed data on the evolution of several active regions as they traversed the face of the sun, disappeared around the limb, then reappeared on the next cycle.

  20. [Noradrenaline and the enzymes of its synthesis and breakdown in the rat hypothalamus after a flight on the Kosmos-936 biosatellite].

    Science.gov (United States)

    Torda, T; Kvetnansky, R; Tigranian, R A; Chulman, J; Genin, A M

    1981-01-01

    In the hypothalamus of the weightless and centrifuged rats flown for 18.5 days on board the biosatellite Cosmos-936 the noradrenaline concentration and activity of the enzymes involved in the catecholamine synthesis and degradation were measured. It was found that under the space flight influence the noradrenaline concentration and tyrosine hydroxylase, dopamine-beta-hydroxylase and monoamine oxidase activities remained unaltered. These findings indicate that a prolonged exposure to weightlessness was not a stressogenic agent that could activate the adrenergic system in the rat hypothalamus.

  1. The vestibulo-ocular reflex and its possible roles in space motion sickness

    Science.gov (United States)

    Watt, Douglas G. D.

    1987-01-01

    Prolonged exposure to an inappropriate vestibulo-ocular reflex (VOR) will usually lead to motion sickness, and it has been predicted on theoretical grounds that VOR gain may be decreased in weightlessness. While experiments during parabolic flight in aircraft tend to confirm this prediction, experiments during orbital spaceflight have led to apparently contradictory results. It is suggested that VOR gain is reduced initially, but that rapid compensatory mechanisms restore it to normal within minutes of reaching weightlessness. However, even though this process may lead to the rapid return of functionally normal gaze stability, it may not protect against the development of motion sickness.

  2. Morphogenetic responses of cultured totipotent cells of carrot /Daucus carota var. carota/ at zero gravity

    Science.gov (United States)

    Krikorian, A. D.; Steward, F. C.

    1978-01-01

    An experiment designed to test whether embryos capable of developing from isolated somatic carrot cells could do so under conditions of weightlessness in space was performed aboard the unmanned Soviet biosatellite Kosmos 782 under the auspices of the joint United States-Soviet Biological Satellite Mission. Space flight and weightlessness seem to have had no adverse effects on the induction of embryoids or on the development of their organs. A portion of the crop of carrot plantlets originated in space and grown to maturity were not morphologically different from controls.

  3. STS-34 Mission Specialist (MS) Chang-Diaz dons EMU during WETF exercises

    Science.gov (United States)

    1989-01-01

    STS-34 Atlantis, Orbiter Vehicle (OV) 104, Mission Specialist (MS) Franklin R. Chang-Diaz dons extravehicular mobility unit (EMU) in preparation for an extravehicular activity (EVA) contingency exercise in JSC's Weightless Environment Training Facility (WETF) Bldg 29 pool. This closeup shows Chang-Diaz straightening his EMU sleeve.

  4. STS-46 MS Chang-Diaz floats in life raft during water egress training at JSC

    Science.gov (United States)

    1992-01-01

    STS-46 Atlantis, Orbiter Vehicle (OV) 104, Mission Specialist (MS) Franklin R. Chang-Diaz, wearing launch and entry suit (LES) and launch and entry helmet (LEH), relies on a one-person life raft to get him to 'safety' during a launch emergency egress (bailout) simulation conducted in JSC's Weightless Environment Training Facility (WETF) Bldg 29 pool.

  5. Revised hypothesis and future perspectives

    DEFF Research Database (Denmark)

    Norsk, P; Drummer, C; Christensen, N J

    2001-01-01

    Results from space have been unexpected and not predictable from the results of ground-based simulations. Therefore, the concept of how weightlessness and gravity modulates the regulation of body fluids must be revised and a new simulation model developed. The main questions to ask in the future ...

  6. 1ST International Conference on Small Satellites: New Technologies, Achievements, Problems And Prospects For International Co-Operation In The New Millenium.

    Science.gov (United States)

    1998-01-01

    composition includes a great deal of high- molecular products of incomplete fuel combustion. The dependence of the condensed phase mass precipitated from the...long presence in conditions simulating weightlessness. ’Kosmicheskaya biologia i meditsma , vol VI, 3, 1972. 18 D J Shapland, W.F. Munroe

  7. The large radius human centrifuge 'A human hypergravity habitat, H

    NARCIS (Netherlands)

    Loon, J.J.W.A. van; Wuyts, F.; Bäcker, N.; Berte, J.; Bok, K.; Bos, J.; Groen, E.; Boyle, R.; Bravenoer, N.; Eekhoff, M.; Chouker, A.; Clement, G.; Cras, P.; Denise, P.; Felsenberg, D.; Fong, K.; Fuller, C.; Heer, M.; Hinghofer-Szalkay, H.; Iwase, S.; Karemaker, J.M.; Linnarsson, D.; Lüthen, C.; Mulder, E.; Narici, M.; Norsk, P.; Paloski, W.; Rutten, M.; Saggini, R.; Stephan, A.; Ullrich, O.; Vautmans, L.; Young, L.

    2009-01-01

    Over the last decades a significant body of knowledge has been gained on the adaptation of the human body going into near weightlessness conditions as well as for the re-adaptation to 1xg Earth conditions after an orbital space flight. Ground-based paradigms for microgravity simulation have been dev

  8. STS-35 Pilot Gardner shoots picture during water egress training at JSC

    Science.gov (United States)

    1990-01-01

    STS-35 Pilot Guy S. Gardner shoots picture using a 35mm camera during water egress training conducted in the Weightless Environment Training Facility (WETF) Bldg 29 at JSC. Gardner is wearing a launch and entry suit and a life jacket.

  9. Microgravity simulation by diamagnetic levitation: effects of a strong gradient magnetic field on the transcriptional profile of Drosophila melanogaster

    NARCIS (Netherlands)

    Herranz, R.; Larkin, O.J.; Dijkstra, C.E.; Hill, R.J.A.; Anthony, P.; Davey, M.R.; Michael, R.; Eaves, L.; van Loon, J.J.W.A.; Medina, F.J.; Marco, R.

    2012-01-01

    Background Many biological systems respond to the presence or absence of gravity. Since experiments performed in space are expensive and can only be undertaken infrequently, Earth-based simulation techniques are used to investigate the biological response to weightlessness. A high gradient magnetic

  10. Simulation of microgravity by magnetic levitation and random positioning: Effect on human A431 cell morphology

    NARCIS (Netherlands)

    Moes, M.J.A.; Gielen, J.C.; Bleichrodt, R.J.; van Loon, J.J.W.A.; Christianen, P.C.M.; Boonstra, J.

    2011-01-01

    Simulation of weightlessness is a desired replenishment for research in microgravity since access to space flights is limited. In real microgravity conditions, the human epidermoid cell line A431 exhibits specific changes in the actin cytoskeleton resulting ultimately in the rounding-up of cells. Th

  11. STS-37 Pilot Kenneth D. Cameron during egress training in JSC's WETF Bldg 29

    Science.gov (United States)

    1990-01-01

    STS-37 Pilot Kenneth D. Cameron, wearing launch and entry suit (LES), discusses simulated emergency egress training on the pool side of JSC's Weightless Environment Training Facility (WETF) Bldg 29. Cameron will be dropped into a simulated ocean, the WETF's 25-ft pool, into which a parachute landing might be made.

  12. Recent NASA aerospace medicine technology developments

    Science.gov (United States)

    Jones, W. L.

    1973-01-01

    Areas of life science are being studied to obtain baseline data, strategies, and technology to permit life research in the space environment. The reactions of the cardiovascular system to prolonged weightlessness are also being investigated. Particle deposition in the human lung, independent respiratory support system, food technology, and remotely controlled manipulators are mentioned briefly.

  13. Space psychology

    Science.gov (United States)

    Parin, V. V.; Gorbov, F. D.; Kosmolinskiy, F. P.

    1974-01-01

    Psychological selection of astronauts considers mental responses and adaptation to the following space flight stress factors: (1) confinement in a small space; (2) changes in three dimensional orientation; (3) effects of altered gravity and weightlessness; (4) decrease in afferent nerve pulses; (5) a sensation of novelty and danger; and (6) a sense of separation from earth.

  14. Working the Continuum between Therapy and Exercise.

    Science.gov (United States)

    Sova, Ruth

    Because of the relative weightlessness factor, water exercise is an excellent low-impact aerobic activity for people with physical difficulties. Participants should inform their physicians of intentions to begin aquatic exercise, and physicians should advise participants that water exercise is exertive. Program instructors must be prepared to…

  15. The large radius human centrifuge 'A human hypergravity habitat, H

    NARCIS (Netherlands)

    Loon, J.J.W.A. van; Wuyts, F.; Bäcker, N.; Berte, J.; Bok, K.; Bos, J.; Groen, E.; Boyle, R.; Bravenoer, N.; Eekhoff, M.; Chouker, A.; Clement, G.; Cras, P.; Denise, P.; Felsenberg, D.; Fong, K.; Fuller, C.; Heer, M.; Hinghofer-Szalkay, H.; Iwase, S.; Karemaker, J.M.; Linnarsson, D.; Lüthen, C.; Mulder, E.; Narici, M.; Norsk, P.; Paloski, W.; Rutten, M.; Saggini, R.; Stephan, A.; Ullrich, O.; Vautmans, L.; Young, L.

    2009-01-01

    Over the last decades a significant body of knowledge has been gained on the adaptation of the human body going into near weightlessness conditions as well as for the re-adaptation to 1xg Earth conditions after an orbital space flight. Ground-based paradigms for microgravity simulation have been

  16. The perception of verticality in lunar and Martian gravity conditions

    NARCIS (Netherlands)

    Winkel, K.N. de; Clément, G.; Groen, E.L.; Werkhoven, P.J.

    2012-01-01

    Although the mechanisms of neural adaptation to weightlessness and re-adaptation to Earth-gravity have received a lot of attention since the first human space flight, there is as yet little knowledge about how spatial orientation is affected by partial gravity, such as lunar gravity of 0.16. g or Ma

  17. Functional preservation of vascular smooth muscle tissue

    Science.gov (United States)

    Alexander, W. C.; Hutchins, P. M.; Kimzey, S. L.

    1973-01-01

    The ionic and cellular feedback relationships operating to effect the vascular decompensatory modifications were examined to reveal procedures for implementing protective measures guarding against vascular collapse when returning from a weightless environment to that of the earth's gravity. The surgical procedures for preparing the rat cremaster, and the fixation methods are described. Abstracts of publications resulting from this research are included.

  18. The large radius human centrifuge 'A human hypergravity habitat, H

    NARCIS (Netherlands)

    Loon, J.J.W.A. van; Wuyts, F.; Bäcker, N.; Berte, J.; Bok, K.; Bos, J.; Groen, E.; Boyle, R.; Bravenoer, N.; Eekhoff, M.; Chouker, A.; Clement, G.; Cras, P.; Denise, P.; Felsenberg, D.; Fong, K.; Fuller, C.; Heer, M.; Hinghofer-Szalkay, H.; Iwase, S.; Karemaker, J.M.; Linnarsson, D.; Lüthen, C.; Mulder, E.; Narici, M.; Norsk, P.; Paloski, W.; Rutten, M.; Saggini, R.; Stephan, A.; Ullrich, O.; Vautmans, L.; Young, L.

    2009-01-01

    Over the last decades a significant body of knowledge has been gained on the adaptation of the human body going into near weightlessness conditions as well as for the re-adaptation to 1xg Earth conditions after an orbital space flight. Ground-based paradigms for microgravity simulation have been dev

  19. NASA space biology accomplishments, 1983-84

    Science.gov (United States)

    Halstead, T. W.; Dutcher, F. R.; Pleasant, L. G.

    1984-01-01

    Approximately 42 project summaries from NASA's Space Biology Program are presented. Emphasis is placed on gravitational effects on plant and animal life. The identification of gravity perception; the effects of weightlessness on genetic integrity, cellular differentiation, reproduction, development, growth, maturation, and senescence; and how gravity affects and controls physiology, morphology, and behavior of organisms are studied.

  20. Ways to Bring a "Far Out" Subject SPACE BIOLOGY Into the Classroom.

    Science.gov (United States)

    Lamb, Janice

    This document describes a grade 10-12 biology course designed to increase student interest by introducing topics in space biology including: the book "Andromeda Strain"; weightlessness; centrifuge; cosmic radiation; space research; origins of life; extraterrestrial life; and the Mars Viking Mission. (SL)

  1. Space Resources for Teachers: Biology, Including Suggestions for Classroom Activities and Laboratory Experiments.

    Science.gov (United States)

    Lee, Tom E.; And Others

    This compilation of resource units concerns the latest developments in space biology. Some of the topics included are oxygen consumption, temperature, radiation, rhythms, weightlessness, acceleration and vibration stress, toxicity, and sensory and perceptual problems. Many of the topics are interdisciplinary and relate biology, physiology,…

  2. A Study of Data Entry Keyboards: The 4 x 4 Keypad.

    Science.gov (United States)

    1985-06-01

    code conversion table. 14 , |*.- . .- :%- Z.:. . K. K * K ;*. * . .o * 4any speech-disabled people, for example, those with severe cerebral palsy ...weightless conditions, menu, diet, sleeping arrangement, exercise , and hygiene considerations. *The shuttle services a variety of functions. These involve

  3. Description, validation, and modification of the Guyton model for space-flight applications. Part A. Guyton model of circulatory, fluid and electrolyte control. Part B. Modification of the Guyton model for circulatory, fluid and electrolyte control

    Science.gov (United States)

    Leonard, J. I.

    1985-01-01

    The mathematical model that has been a cornerstone for the systems analysis of space-flight physiological studies is the Guyton model describing circulatory, fluid and electrolyte regulation. The model and the modifications that are made to permit simulation and analysis of the stress of weightlessness are described.

  4. Gravity: Simple Experiments for Young Scientists.

    Science.gov (United States)

    White, Larry

    This book contains 12 simple experiments through which students can learn about gravity and its implications. Some of the topics included are weight, weightlessness, artificial gravity, the pull of gravity on different shapes, center of gravity, the universal law of gravity, and balancing. Experiments include: finding the balancing point; weighing…

  5. Frog egg growth, experiment S003

    Science.gov (United States)

    Young, R. S.; Tremor, J. W.

    1971-01-01

    The objective of experiment was to determine the effect of weightlessness on the ability of a fertilized frog egg to divide normally and to differentiate and form a normal embryo. This experiment was first attempted on the Gemini 8 mission and was completed only partially because of the early termination of that mission.

  6. [Amino acid composition of the rat quadriceps femoris muscle after a flight on the Kosmos-936 biosatellite].

    Science.gov (United States)

    Vlasova, T F; Miroshnikova, E B; Poliakov, V V; Murugova, T P

    1982-01-01

    The amino acid composition of the quadriceps muscle of rats flown onboard the biosatellite Cosmos-936 and exposed to the ground-based synchronous control experiment was studied. The weightless rats showed changes in the amino acid concentration in the quadriceps muscle. The centrifuged flight and synchronous rats displayed an accumulation of free amino acids in the above muscle.

  7. Main results of the experiments conducted during the flight of the Kosmos-1129 Biosatellite and the status of preparation of studies on the next biosatllite

    Science.gov (United States)

    Ilin, E. A.

    1980-01-01

    Experiments included studies on the biological effects of weightlessness. Space flight stress, disorientation, and physiological factors are discussed for each experimental subject. The subjects included rats, drosophila flies, and plants. Metabolic rates were monitored along with other changes in the subject's activity cycles.

  8. JPRS Report, Soviet Union, Aviation & Cosmonautics, No. 12, December 1987

    Science.gov (United States)

    2007-11-02

    tissue. The results of experiments on animals carried out during flights of Kosmos series biosatellites made it possible to efficiently schedule...ration are a good means of protecting against accelera- tions after weightlessness. Soviet biosatellites of the Kosmos series are making a noticeable...tal research aboard Kosmos biosatellites, Interkosmos satellites and manned orbiting stations. Working together with specialists of the GDR

  9. Vestibular adaption to an altered gravitational environment: consequences for spatial orientation

    NARCIS (Netherlands)

    Nooij, S.A.E.

    2008-01-01

    Earth's gravity is an omnipresent factor in human life and provides a strong reference for spatial orientation. Changes in the prevailing gravity level, like the transition to weightlessness during space flight, affect spatial orientation and require adaptation of many physiological processes involv

  10. Microgravity simulation by diamagnetic levitation: effects of a strong gradient magnetic field on the transcriptional profile of Drosophila melanogaster

    NARCIS (Netherlands)

    Herranz, R.; Larkin, O.J.; Dijkstra, C.E.; Hill, R.J.A.; Anthony, P.; Davey, M.R.; Michael, R.; Eaves, L.; van Loon, J.J.W.A.; Medina, F.J.; Marco, R.

    2012-01-01

    Background Many biological systems respond to the presence or absence of gravity. Since experiments performed in space are expensive and can only be undertaken infrequently, Earth-based simulation techniques are used to investigate the biological response to weightlessness. A high gradient magnetic

  11. Simulation of microgravity by magnetic levitation and random positioning: Effect on human A431 cell morphology

    NARCIS (Netherlands)

    Moes, M.J.A.; Gielen, J.C.; Bleichrodt, R.J.; van Loon, J.J.W.A.; Christianen, P.C.M.; Boonstra, J.

    2011-01-01

    Simulation of weightlessness is a desired replenishment for research in microgravity since access to space flights is limited. In real microgravity conditions, the human epidermoid cell line A431 exhibits specific changes in the actin cytoskeleton resulting ultimately in the rounding-up of cells. Th

  12. Research opportunities in muscle atrophy

    Science.gov (United States)

    Herbison, G. J. (Editor); Talbot, J. M. (Editor)

    1984-01-01

    Muscle atrophy in a weightless environment is studied. Topics of investigation include physiological factors of muscle atrophy in space flight, biochemistry, countermeasures, modelling of atrophied muscle tissue, and various methods of measurement of muscle strength and endurance. A review of the current literature and suggestions for future research are included.

  13. Effects of Inactivity and Exercise on Bone.

    Science.gov (United States)

    Smith, Everett L.; Gilligan, Catherine

    1987-01-01

    Research has shown that bone tissue responds to the forces of gravity and muscle contraction. The benefits of weight-bearing exercise in preventing or reversing bone mass loss related to osteoporosis is reviewed. The effects of weightlessness and immobilization, and the possible effects of athletic amenorrhea, on bone mineral density are…

  14. Underwater EVA training in the WETF with astronaut Robert L. Stewart

    Science.gov (United States)

    1983-01-01

    Underwater extravehicular activity (EVA) training in the weightless environment training facility (WETF) with astronaut Robert L. Stewart. Stewart is simulating a planned EVA using the mobile foot restraint device and a one-G version of the Canadian-built remote manipulator system.

  15. The first dedicated life sciences mission - Spacelab 4

    Science.gov (United States)

    Cramer, D. R.; Reid, D. H.; Klein, H. P.

    1983-01-01

    The details of the payload and the experiments in Spacelab 4, the first Spacelab mission dedicated entirely to the life sciences, are discussed. The payload of Spacelab 4, carried in the bay of the Shuttle Orbiter, consists of 25 tentatively selected investigations combined into a comprehensive integrated exploration of the effects of acute weightlessness on living systems. The payload contains complementary designs in the human and animal investigations in order to validate animal models of human physiology in weightlessness. Animals used as experimental subjects will include squirrel monkeys, laboratory rats, several species of plants, and frog eggs. The main scientific objectives of the investigations include the study of the acute cephalic fluid shift, cardiovascular adaptation to weightlessness, including postflight reductions in orthostatic tolerance and exercise capacity, and changes in vestibular function, including space motion sickness, associated with weightlessness. Other scientific objective include the study of red cell mass reduction, negative nitrogen balance, altered calcium metabolism, suppressed in vitro lymphocyte reactivity, gravitropism and photropism in plants, and fertilization and early development in frog eggs.

  16. Space flight research relevant to health, physical education, and recreation: With particular reference to Skylab's life science experiments

    Science.gov (United States)

    Vanhuss, W. D.; Heusner, W. W.

    1979-01-01

    Data collected in the Skylab program relating to physiological stresses is presented. Included are routine blood measures used in clinical medicine as research type endocrine analyses to investigate the metabolic/endocrine responses to weightlessness. The daily routine of physical exercise, coupled with appropriate dietary intake, sleep, work, and recreation periods were considered essential in maintaining the crew's health and well being.

  17. Parathyroid hormone, calcitonin, and vitamin D 1974: Present status of physiological studies and analysis of calcium homeostasis

    Science.gov (United States)

    Potts, J. T., Jr.; Swenson, K. G.

    1975-01-01

    The role of parathyroid hormone, calcitonin, and vitamin D in the control of calcium and bone metabolism was studied. Particular emphasis was placed on the physiological adaptation to weightlessness and, as a potential model for this purpose, on the immobilization characteristic of space flight or prolonged bed rest. The biosynthesis, control of secretion, and metabolism of these hormonal agents is considered.

  18. Europe/Latin America Report, Science and Technology

    Science.gov (United States)

    2007-11-02

    the future solar arrays. This experiment is to correlate the deployment tests under ideal conditions of weightlessness. It will take place this time... Casa for a joint study of the possibility of a light combat helicopter that would be available in the mid-1990«s. Boeing That seems to be everything

  19. Astronauts Mullane and Resnik at WETF training

    Science.gov (United States)

    1984-01-01

    Astronauts Judith A. Resnik and Richard M. (Mike) Mullane, 41-D mission specialists, participate in an underwater session in the JSC weightless environment training facility (WETF). In this close-up view, Resnik adjusts Mullane's helmet prior to his immersion in the pool.

  20. Parathyroid hormone, calcitonin, and vitamin D 1974: Present status of physiological studies and analysis of calcium homeostasis

    Science.gov (United States)

    Potts, J. T., Jr.; Swenson, K. G.

    1975-01-01

    The role of parathyroid hormone, calcitonin, and vitamin D in the control of calcium and bone metabolism was studied. Particular emphasis was placed on the physiological adaptation to weightlessness and, as a potential model for this purpose, on the immobilization characteristic of space flight or prolonged bed rest. The biosynthesis, control of secretion, and metabolism of these hormonal agents is considered.

  1. Views of the STS-5 Science Press briefing with Student Experimenters

    Science.gov (United States)

    1982-01-01

    Views of the STS-5 Science Press briefing with Student Experimenters. Photos include Michelle Issel of Wallingfor, Connecticut showing her studen experiment dealing with the formation of crystals in a weightless environment (37862); Aaron Gillette of Winter Haven, Florida displaying his student experiment dealing with the growth of Porifera in zero gravity (37863).

  2. STS-46 MS Chang-Diaz floats in life raft during water egress training at JSC

    Science.gov (United States)

    1992-01-01

    STS-46 Atlantis, Orbiter Vehicle (OV) 104, Mission Specialist (MS) Franklin R. Chang-Diaz, wearing launch and entry suit (LES) and launch and entry helmet (LEH), relies on a one-person life raft to get him to 'safety' during a launch emergency egress (bailout) simulation conducted in JSC's Weightless Environment Training Facility (WETF) Bldg 29 pool.

  3. Neuromuscular adaptations during long-term bed rest

    NARCIS (Netherlands)

    Mulder, E.R.

    2007-01-01

    The weightless environment encountered during human spaceflight virtually eliminates the mechanical loading of the human body. The accompanying physical inactivity sets in motion a cascade of changes that affects practically every physiological system in the human body. Of particular medical and

  4. Surveillance, Big Data Analytics and the Death of Privacy

    Science.gov (United States)

    Doughty, Howard A.

    2014-01-01

    In this article, Howard Doughty examines how today's technological devices alter and increasingly substitute for one's body/mind, sociality and (a)morality. He claims that today, under the crushing weightlessness of virtuality, citizens are less confident, more willing to retreat into the idiocy of private life. He goes on to address the…

  5. Researchers make the best argument yet that neutrinos are capable of changing form

    CERN Multimedia

    Johnson, G

    2002-01-01

    Measurements by the Kamioka underground laboratory in Japan have made the most persuasive case yet that particles called are capable of changing identity in midflight. The experiment also confirms that neutrinos, long thought to be weightless, have a tiny bit of mass. Otherwise, theory holds, they would not be capable of changing form, called oscillation (1 page).

  6. Influence of altered gravity on the cytochemical localization of cytochrome oxidase activity in central and peripheral gravisensory systems in developing cichlid fish

    Science.gov (United States)

    Paulus, U.; Nindl, G.; Körtje, K. H.; Slenzka, K.; Neubert, J.; Rahmann, H.

    Cichlid fish larvae were reared from hatching to active free swimming under different gravity conditions: natural environment, increased acceleration in a centrifuge, simulated weightlessness in a clinostat and near weightlessness during space flight. Cytochrome oxidase activity was analyzed semiquantitatively on the ultrastructural level as a marker of regional neuronal activity in a primary, vestibular brainstem nucleus and in gravity receptive epithelia in the inner ear. Our results show, that gravity seems to be positively correlated with cytochrome oxidase activity in the magnocellular nucleus of developing fish brain. In the inner ear the energy metabolism is decreased under microgravity concerning utricle but not saccule. Hypergravity has not effect on cytochrome oxidase activity in sensory inner ear epithelia.

  7. Microflow1, a sheathless fiber-optic flow cytometry biomedical platform: demonstration onboard the international space station.

    Science.gov (United States)

    Dubeau-Laramée, Geneviève; Rivière, Christophe; Jean, Isabelle; Mermut, Ozzy; Cohen, Luchino Y

    2014-04-01

    A fiber-optic based flow cytometry platform was designed to build a portable and robust instrument for space applications. At the core of the Microflow1 is a unique fiber-optic flow cell fitted to a fluidic system and fiber coupled to the source and detection channels. A Microflow1 engineering unit was first tested and benchmarked against a commercial flow cytometer as a reference in a standard laboratory environment. Testing in parabolic flight campaigns was performed to establish Microflow1's performance in weightlessness, before operating the new platform on the International Space Station. Microflow1 had comparable performances to commercial systems, and operated remarkably and robustly in weightlessness (microgravity). Microflow1 supported immunophenotyping as well as microbead-based multiplexed cytokine assays in the space environment and independently of gravity levels. Results presented here provide evidence that this fiber-optic cytometer technology is inherently compatible with the space environment with negligible compromise to analytical performance.

  8. A Brief Review of Bone Adaptation to Unloading

    Institute of Scientific and Technical Information of China (English)

    Ping Zhang; Kazunori Hamamura; Hiroki Yokota

    2008-01-01

    Weight-bearing bone is constantly adapting its structure and function to mechanical environments. Loading through routine exercises stimulates bone formation and prevents bone loss, but unloading through bed rest and cast immobilization as well as exposure to weightlessness during spaceflight reduces its mass and strength. In order to elucidate the mechanism underlying unloading-driven bone adaptation, ground-based in vitro and in vivo analyses have been conducted using rotating cell culturing and hindlimb suspension. Focusing on gene expression studies in osteoblasts and hindlimb suspension studies, this minireview introduces our recent understanding on bone homeostasis under weightlessness in space. Most of the existing data indicate that unloading has the opposite effects to loading through common signaling pathways. However, a question remains as to whether any pathway unique to unloading (and not to loading) may exist.

  9. Renal and sympathoadrenal responses in space

    DEFF Research Database (Denmark)

    Christensen, N J; Drummer, C; Norsk, P

    2001-01-01

    According to a classic hypothesis, weightlessness should promote the renal excretion rate of sodium and water and lead to a fluid- and electrolyte-depleted state. This hypothesis is based on experiments in which weightlessness has been simulated in humans by head-down bed rest and water immersion....... However, after 5 to 6 days of space mission, the diuretic and natriuretic responses to an intravenous isotonic saline load were attenuated and plasma norepinephrine and renin concentrations increased compared with those of the acute supine position before flight. Renal fluid excretion after an oral water...... activity is increased during space flights as measured using plasma concentration and urinary excretion of norepinephrine and epinephrine. The space-induced activation of antinatriuretic mechanisms and sympathoadrenal activity could have been caused by early in-flight reduction in total and central blood...

  10. Space motion sickness preflight adaptation training Preliminary studies with prototype trainers

    Science.gov (United States)

    Parker, D. E.; Ouyang, L.; Rock, J. C.; Von Gierke, H. E.; Reschke, M. F.

    1985-01-01

    Based on the otolith tilt-translation reinterpretation hypothesis (Parker et al., 1985), preflight adaptation procedures and several preflight adaptation trainers (PATs) have been developed. Two PAT prototypes, the Miami University Seesaw (MUS) and the Dynamic Environmental Simulator (DES), include a physical room that is moved relative to the restrained subject. Results from the MUS and DES PAT experiments indicate that exposure to the produced sensory rearrangement can change eye movement reflexes. The changes persisted for a period longer than the training exposure period, indicating similarity with the eye-movement reflexes observed immediately postflight in weightlessness-adapted astronauts. It is concluded that the apparatus and procedures to preadapt astronauts to the sensory rearrangement of weightless space flight can be developed on the basis of the reported PATs and procedures. The third PAT prototype tested, which employs a computer-generated scene, failed to produce changes similar to those recorded in the MUS and DES experiments.

  11. Rheoceptive mediators of graviperception in a water flea: Morphological implications of antennal-socket setae in daphnia magna

    Science.gov (United States)

    Meyers, D. G.

    1984-01-01

    Aquatic microcrustaceans of the genus Daphnia are known to orient to light during the day. At night, in the absence of visual cues, daphnids were suspected of maintaining equilibrium by monitoring the direction of gravity through their swimming antennae. Recent investigations using simulated, weightlessness conditions coupled with absence of illumination revealed hair like structures or setae on the basal, articulating socket of the antennae that, when surgically removed, resulted in disorientation. Given the simulated weightlessness or neutrally buoyant condition that eliminated sinking of the normally negatively buoyant Daphnia, it was proposed that the antennal socket setae function as rheoceptors stimulated by the upward rush of water currents during gravity induced, sinking phase of daphnid swimming movements. This rheoceptively mediated, gravity perception hypothesis is further supported by morphological investigations. Scanning electron micrographs indicate that antennal socket setae are anatomically similar to proprioceptors used by higher crustaceans to monitor gravitational direction.

  12. Human physiological adaptation to extended Space Flight and its implications for Space Station

    Science.gov (United States)

    Kutyna, F. A.; Shumate, W. H.

    1985-01-01

    Current work evaluating short-term space flight physiological data on the homeostatic changes due to weightlessness is presented as a means of anticipating Space Station long-term effects. An integrated systems analysis of current data shows a vestibulo-sensory adaptation within days; a loss of body mass, fluids, and electrolytes, stabilizing in a month; and a loss in red cell mass over a month. But bone demineralization which did not level off is seen as the biggest concern. Computer algorithms have been developed to simulate the human adaptation to weightlessness. So far these paradigms have been backed up by flight data and it is hoped that they will provide valuable information for future Space Station design. A series of explanatory schematics is attached.

  13. Endocrine and metabolic changes in payload specialist (L-1)

    Science.gov (United States)

    Matsui, Nobuo

    1993-01-01

    The endocrine system plays an important role in the adaptation to unusual environments by secreting hormones to control metabolism. Since human beings have long evolved on the surface of the Earth under a gravity environment, the weightless environment must be quite unusual for them. The purpose of this experiment is to study the mechanisms of human adaptation to a weightless environment from endocrine and metabolic changes. Our study plan is focused on four major physiological changes which were reported during past space flights or which may be expected to occur under that condition: (1) hormone and metabolic changes associated with fluid shift; (2) bone demineralization and muscle atrophy; (3) altered circadian rhythm; and (4) stress reaction during space flight.

  14. Femur-bending properties as influenced by gravity. IV - Limits after high and low weight-bearing

    Science.gov (United States)

    Wunder, C. C.; Tipton, C. M.; Cook, K. M.

    1980-01-01

    Gravity enhances femur growth as measured in terms of strength, but shows little or even a growth-retarding effect in terms of relative brittleness, defined as the inverse of ultimate or tolerable strain. Chronic weightlessness was simulated by harness suspension or by extrapolation of results from 3-g centrifugation. Experimental results from 45 male, white rats (34-520 d old) were compared to 72 control or baseline rats (28-520 d old) with correction for age and size differences. After suspension, the youngest rats showed subnormal tolerable strains. Combined results, however, although predicting 19 + or 1% below normal strength, after a week of weightlessness, predicted less effect (1 + or - 4%) for the tolerable strain.

  15. [Energy reactions in the skeletal muscles of rats after a flight on the Kosmos-1129 biosatellite].

    Science.gov (United States)

    Mailian, E S; Buravkova, L B; Kokoreva, L V

    1983-01-01

    The polarographic analysis of biological oxidation in rat skeletal muscles after the 18.5-day flight revealed changes specific for the flight animals: oxidative phosphorylation uncoupling, distinct inertness of energy accumulation 10 hrs after recovery. Tissue respiration inhibition occurred in both flight and synchronous rats suggesting the effect of other than weightlessness factors. In the flight animals the parameters of energy metabolism returned to the prelaunch level within a longer (29 days) time than in the synchronous rats (6 days). Muscles of different function (predominance of fast or slow fibers) showed similar responses of energy metabolism to weightlessness, i. e. inhibition of the intensity and decrease of the energy efficiency of oxidative processes.

  16. Cell morphological, ontogenic, and genetic reactions to 0-g simulation and hyper-g.

    Science.gov (United States)

    Briegleb, W; Neubert, J; Schatz, A; Hordinsky, J R; Cogoli, A

    1982-01-01

    Organisms use gravity for spatial orientation, and differentiation into species during evolution follows geological processes which are caused by gravity. On the other hand, the task of most organismic functions which have or may have a relation to gravity is to compensate gravity. Furthermore, today it is very obvious that organisms do not disintegrate under the conditions of weightlessness, at least for the currently tested durations. These previous statements indicate a large field of still unknown regulation and adaptation mechanisms. Experiments to simulate weightlessness on the fast clinostat and with hyper-g show a highly developed ability of the genetic chain and of differentiating cells in being autonomous against mechanical stresses caused by outer accelerations. Nevertheless, different strong and slight changes of different tested end points were found. The question remains if the cells react actively or only passively.

  17. Animals in biomedical space research

    Science.gov (United States)

    Phillips, Robert W.

    The use of experimental animals has been a major component of biomedical research progress. Using animals in space presents special problems, but also provides special opportunities. Rat and squirrel monkeys experiments have been planned in concert with human experiments to help answer fundamental questions concerning the effect of weightlessness on mammalian function. For the most part, these experiments focus on identified changes noted in humans during space flight. Utilizing space laboratory facilities, manipulative experiments can be completed while animals are still in orbit. Other experiments are designed to study changes in gravity receptor structure and function and the effect of weightlessness on early vertebrate development. Following these preliminary animals experiments on Spacelab Shuttle flights, longer term programs of animal investigation will be conducted on Space Station.

  18. Evaporative water loss in man in a gravity-free environment

    Science.gov (United States)

    Leach, C. S.; Leonard, J. I.; Rambaut, P. C.; Johnson, P. C.

    1978-01-01

    Daily evaporative water losses (EWL) during the three Skylab missions were measured indirectly using mass and water-balance techniques. The mean daily values of EWL for the nine crew members who averaged 1 hr of daily exercise were: preflight 1,750 + or - 37 (SE) ml or 970 + or - 20 ml/sq m and inflight 1,560 + or - 26 ml or 860 + or - 14 ml/sq m. Although it was expected the EWL would increase in the hypobaric environment of Skylab, an average decrease from preflight sea-level conditions of 11% was measured. The results suggest that weightlessness decreased sweat losses during exercise and possibly reduced insensible skin losses. The weightlessness environment apparently promotes the formation of an observed sweat film on the skin surface during exercise by reducing convective flow and sweat drippage, resulting in high levels of skin wettedness that favor sweat suppression.

  19. A parallelized particle tracing code for CFD simulations in Earth Sciences

    OpenAIRE

    Vlad Constantin Manea; Marina Manea; Mihai Pomeran; Lucian Besutiu; Luminita Zlagnean

    2012-01-01

    The problem of convective flows in a highly viscous fluid represents a common research direction in Earth Sciences. In order to trace the convective motion of the fluid material, a source of passive particles (or tracers) that flow at a local convection velocity and do not affect the pattern of flow is commonly used. It is presented a parallelized tracer code that uses passive and weightless particles with their position computed from their displacement during a small time interval at the vel...

  20. The Application of Systems Analysis and Mathematical Models to the Study of Erythropoiesis During Space Flight

    Science.gov (United States)

    Leonard, J. I.

    1974-01-01

    Included in the report are: (1) review of the erythropoietic mechanisms; (2) an evaluation of existing models for the control of erythropoiesis; (3) a computer simulation of the model's response to hypoxia; (4) an hypothesis to explain observed decreases in red blood cell mass during weightlessness; (5) suggestions for further research; and (6) an assessment of the role that systems analysis can play in the Skylab hematological program.

  1. Research and Diplomacy 350 Kilometers above the Earth

    CERN Document Server

    CERN. Geneva

    2017-01-01

    The International Space Station is a tour de force, not simply in engineering and R&D, but in the unprecedented collaboration, synergy, and entente the partners have displayed through its planning, construction, and, now, utilisation phase. Orbiting 350 km above the surface of the Earth, the ISS is the only weightless research laboratory currently in operation and has been inhabited by multi-national crew since November 2001. Ms. Payette takes us on a space journey where science merges with diplomacy.

  2. Urinary albumin in space missions

    DEFF Research Database (Denmark)

    Cirillo, Massimo; De Santo, Natale G; Heer, Martina

    2002-01-01

    Proteinuria was hypothesized for space mission but research data are missing. Urinary albumin, as index of proteinuria, was analyzed in frozen urine samples collected by astronauts during space missions onboard MIR station and on ground (control). Urinary albumin was measured by a double antibody...... radioimmunoassay. On average, 24h urinary albumin was 27.4% lower in space than on ground; the difference was statistically significant. Low urinary albumin excretion could be another effect of exposure to weightlessness (microgravity)....

  3. Student Lloyd C. Bruce listens to MS John M. Lounge in CSR during STS-26

    Science.gov (United States)

    1988-01-01

    Seated in the customer support room (CSR) of JSC's Mission Control Center (MCC) Bldg 30, student experimenter Lloyd C. Bruce listens to Mission Specialist (MS) John M. Lounge onboard Discovery, Orbiter Vehicle (OV) 103, during the STS-26 mission. Bruce's student experiment 82-4 (SE82-4) 'The Effects of Weightlessness on Grain Formation and Strength in Metals' is onboard OV-103. Lounge is visible in the television (TV) monitor on the left.

  4. Close-up locker scene of material belonging to Payload specialist Neri

    Science.gov (United States)

    1985-01-01

    Close-up locker scene of materials belonging to Payload specialist Rodolfo Neri. Items include a Morelos satellite decal, the crest of the Universidad Nacional Autonoma de Mexico (Neri's alma mater), and one of the plant experiments he monitored during the flight. The experiment at bottom frame is the Transportation of Nutrients in a Weightless Environment (TRANSPORT). A pair of scissors are on the locker and a pen floats above it.

  5. Gravity and the cells of gravity receptors in mammals

    Science.gov (United States)

    Ross, M. D.

    Two new findings, that crystals located in the inner ear gravity receptors of mammals have the internal organization requisite for the piezoelectric property, and that sensory hair cells of these same receptors possess contractile-appearing striated organelles, have prompted the author to model mammalian gravity receptors in the ear on the principles of piezoelectricity and bioenergetics. This model is presented and a brief discussion of its implications for the possible effects of weightlessness follows.

  6. Vapor Crystal Growth (VCG) experiment Cell

    Science.gov (United States)

    1992-01-01

    The image shows a test cell of Crystal Growth experiment inside the Vapor Crystal Growth System (VCGS) furnace aboard the STS-42, International Microgravity Laboratory-1 (IML-1), mission. The goal of IML-1, a pressurized marned Spacelab module, was to explore in depth the complex effects of weightlessness of living organisms and materials processing. More than 200 scientists from 16 countires participated in the investigations.

  7. Space research on organs and tissues

    Science.gov (United States)

    Tischler, Marc E.; Morey-Holton, Emily

    1992-01-01

    The effects of microgravity on various physiological systems are reviewed focusing on muscle, bone, cardiovascular, pulmonary, neurovestibular, liver, and endocrine systems. It is noted that certain alterations of organs and tissues caused by microgravity are not reproducible in earth-bound animal or human models. Thus space research on organs and tissues is essential for both validating the earth-bound models used in laboratories and studying the adaptations to weightlessness which cannot be mimicked on earth.

  8. Urinary albumin in space missions

    DEFF Research Database (Denmark)

    Cirillo, Massimo; De Santo, Natale G; Heer, Martina

    2002-01-01

    Proteinuria was hypothesized for space mission but research data are missing. Urinary albumin, as index of proteinuria, was analyzed in frozen urine samples collected by astronauts during space missions onboard MIR station and on ground (control). Urinary albumin was measured by a double antibody...... radioimmunoassay. On average, 24h urinary albumin was 27.4% lower in space than on ground; the difference was statistically significant. Low urinary albumin excretion could be another effect of exposure to weightlessness (microgravity)....

  9. STS-38 Mission Specialist (MS) Robert C. Springer dons EMU in JSC's WETF

    Science.gov (United States)

    1990-01-01

    STS-38 Mission Specialist (MS) Robert C. Springer, wearing extravehicular mobility unit (EMU), fastens the strap on his communications carrier assembly (CCA) cap during suit donning in JSC's Weightless Environment Training Facility (WETF) Bldg 29. Positioned on the WETF platform at pool side, Springer is preparing for an underwater extravehicular activity (EVA) simulation. During the training exercise, Springer will rehearse contingency EVA procedures for the STS-38 mission aboard Atlantis, Orbiter Vehicle (OV) 104.

  10. LoRa for the Internet of Things

    OpenAIRE

    Bor, Martin; Vidler, John Edward; Roedig, Utz

    2016-01-01

    New transceiver technologies have emerged which enable power efficient communication over very long distances. Examples of such Low-Power Wide-Area Network (LPWAN)technologies are LoRa, Sigfox and Weightless. A typicalapplication scenario for these technologies is city wide meter reading collection where devices send readings at very low frequency over a long distance to a data concentrator (one-hop networks). We argue that these transceiversare potentially very useful to construct more gener...

  11. Left to right, astronauts John H. Casper, mission commander, and Curtis L. Brown, Jr., pilot, get

    Science.gov (United States)

    1996-01-01

    STS-77 TRAINING VIEW --- Left to right, astronauts John H. Casper, mission commander, and Curtis L. Brown, Jr., pilot, get help with the final touches of suit donning during emergency bailout training for STS-77 crew members in the Johnson Space Centers (JSC) Weightless Environment Training Facility (WET-F). Casper and Brown will join four other astronauts for nine days aboard the Space Shuttle Endeavour next month.

  12. Mineral balance, experiment M071. [space flight effects on human mineral metabolism

    Science.gov (United States)

    Whedon, G. D.; Rambaut, P. C.; Smith, M. C., Jr.

    1973-01-01

    Concern for the long term metabolic consequences of weightless flight was the basis for the conception of the Skylab medical experiment to measure mineral balance. Proper interpretation of obtained data that diminished atmospheric pressure has no appreciable effect, or at least no protective effect, on calcium metabolism. The absence of changes in calcium metabolism indicates that a stable baseline observation has been made for Skylab as far as the effects of atmosphere or calcium metabolism are concerned.

  13. Development of Ag-Cu-Zn-Sn brazing filler metals with a 1 0 weight-% reduction of silver and same liquidus temperature

    Institute of Scientific and Technical Information of China (English)

    Daniel Schnee; Gunther Wiehl; Sebastian Starck; Chen Kevin

    2014-01-01

    With BrazeTec BlueBraze the manufacturers in HVACR industry have an alternative filler metal with 10 weight-%less silver but same brazing temperatures.The performance of these new alloys has been evaluated in several tests.The evaluation included wetting investigations,metallographic examinations,joint strength at different temperatures and pulsation and corrosion resistance.The results ofthese tests will be presented in this paper.

  14. STS-38 Mission Specialist (MS) Robert C. Springer dons EMU in JSC's WETF

    Science.gov (United States)

    1990-01-01

    STS-38 Mission Specialist (MS) Robert C. Springer dons extravehicular mobility unit (EMU) upper torso with technicians' assistance in JSC's Weightless Environment Training Facility (WETF) Bldg 29. Positioned on the WETF platform at pool side, Springer is preparing for an underwater extravehicular activity (EVA) simulation. During the training session, Springer will rehearse contingency EVA procedures for the STS-38 mission aboard Atlantis, Orbiter Vehicle (OV) 104.

  15. Determination of oxygen tension in the subcutaneous tissue of cosmonauts during the Salyut-6 mission

    Science.gov (United States)

    Baranski, S.; Bloszczynski, R.; Hermaszewski, M.; Kubiczkowa, J.; Piorko, A.; Saganiak, R.; Sarol, Z.; Skibniewsky, F.; Stendera, J.; Walichnowski, W.

    1982-01-01

    A polarographic technique was used to measure the oxygen tension in subcutaneous tissue of the forearm of a cosmonaut prior to, after, and on the fourth day of a space mission performed by Salut-6. A drop in the oxygen exchange rate in the peripheral tissues during weightlessness was observed. The mechanisms of this change are studied, taking into consideration the blood distribution in the organism and microcirculation disorders reflected by a decreased blood flow rate in arterial-venous junctions.

  16. Understanding metabolic alterations in space flight using quantitative models - Fluid and energy balance

    Science.gov (United States)

    Leonard, J. I.

    1985-01-01

    The results of an integrated multidisciplinary and multiexperimental investigation, using data from the Skylab program, of metabolic adaptation to space flight are summarized and discussed. The effects of space flight on fluid-electrolyte regulation, mechanisms of hormone disturbances, energy balance, and the etiology of weight loss are emphasized. A composite picture of the fluid, electrolyte, and energy response to weightlessness, based primarily on data gathered from the nine Skylab crewmen, is presented.

  17. STS-47 Astronaut Crew Training Clip

    Science.gov (United States)

    1992-01-01

    The crew of STS-47, Commander Robert L. Gibson, Pilot Curtis L. Brown, Payload Commander Mark C. Lee, Mission Specialists N. Jan Davis, Jay Apt, and Mae C. Jemison, and Payload Specialist Mamoru Mohri, is seen during various parts of their training, including SAREX training in the Full Fuselage Trainer (FFT), firefighting training. A familiarization flight in the KC-135, a food tasting, photo training in the Crew Compartment Trainer, and bailout training in the Weightless Environment Training Facility (WETF) are also shown.

  18. An evaluation of low-cost payload carrier

    Science.gov (United States)

    Yost, V. H.

    1980-01-01

    Payload carrier designed for space vehicles is essentially cargo carrier that supports, positions, and protects various equipment and materials used in conducting experiments in weightless space environment. Proposed carrier entitled Materials Experiment Assembly II (MEA-II) is considered superior to previously developed models in size, weight, and cost to user. Structure is lightweight with insulated exterior and can be custom sized to meet user needs.

  19. Homoclinic, Subharmonic and Superharmonic Bifurcations for a Pendulum with Periodically Varying Length

    CERN Document Server

    Belyakov, Anton O

    2014-01-01

    Dynamic behavior of a weightless rod with a point mass sliding along the rod axis according to periodic law is studied. This is the simplest model of child's swing. Melnikov's analysis is carried out to find bifurcations of homoclinic, subharmonic oscillatory, and subharmonic rotational orbits. For the analysis of superharmonic rotational orbits the averaging method is used and stability of obtained approximate solution is checked. The analytical results are compared with numerical simulation results.

  20. [PHYSIOLAB project for CASSIOPEE: the space cardiovascular exploratory laboratory].

    Science.gov (United States)

    Louisy, F

    1996-01-01

    The French Health Defense Service is concerned by the finalization and the implementation of the PHYSIOLAB laboratory. In July 1996, PHYSIOLAB will participate to the french--russian mission CASSIOPEE. It is a functional exploratory laboratory which will support a programm of scientific experiments whose aim is to better understand cardiovascular deconditioning under weightlessness and to implement medical monitoring of cosmonauts during next french-russian space missions. In this paper, functional and scientific aims, and structure of PHYSIOLAB are described.

  1. The influence of the calibration standard and the chemical composition of the water samples residue in the counting efficiency of proportional detectors for gross alpha and beta counting. Application on the radiologic control of the IPEN-CNEN/SP; A influencia do padrao de calibracao e da composicao do residuo de amostras de agua na eficiencia de contadores proporcionais para contagem alfa e beta total. Aplicacao no controle radiologico do IPEN-CNEN/SP

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Cecilia Martins

    2003-07-01

    In this work the efficiency calibration curves of thin-window and low background gas-flow proportional counters were determined for calibration standards with different energies and different absorber thicknesses. For the gross alpha counting we have used {sup 241}Am and natural uranium standards and for the gross beta counting we have used {sup 90}Sr/{sup 90}Y and {sup 137}Cs standards in residue thicknesses ranging from 0 to approximately 18 mg/cm{sup 2}. These sample thicknesses were increased with a previously determined salted solution prepared simulating the chemical composition of the underground water of IPEN The counting efficiency for alpha emitters ranged from 0,273 +- 0,038 for a weightless residue to only 0,015 +- 0,002 in a planchet containing 15 mg/cm{sup 2} of residue for {sup 241}Am standard. For natural uranium standard the efficiency ranged from 0,322 +- 0,030 for a weightless residue to 0,023 +- 0,003 in a planchet containing 14,5 mg/cm{sup 2} of residue. The counting efficiency for beta emitters ranged from 0,430 +- 0,036 for a weightless residue to 0,247 +- 0,020 in a planchet containing 17 mg/cm{sup 2} of residue for {sup 137}Cs standard. For {sup 90}Sr/{sup 90}Y standard the efficiency ranged from 0,489 +- 0,041 for a weightless residue to 0,323 +- 0,026 in a planchet containing 18 mg/cm{sup 2} of residue. Results make evident the counting efficiency variation with the alpha or beta emitters energies and the thickness of the water samples residue. So, the calibration standard, the thickness and the chemical composition of the residue must always be considered in the gross alpha and beta radioactivity determination in water samples. (author)

  2. Thermal convection driven by acoustic field under microgravity

    OpenAIRE

    Tanabe, Mitsuaki; 田辺 光昭

    2007-01-01

    Natural convection is suppressed in space environment due to the weightlessness. Only centrifugal force is utilized currently to drive gas-phase thermal convection in space. This paper presents an alternative way to drive thermal convection. From the investigation of combustion oscillation in rocket motors, a new thermal convection had been found in stationary acoustic fields. Analyzing the phenomena, acoustic radiation force is found to be the candidate driving force. With a simplified syste...

  3. Red blood cell and iron metabolism during space flight

    Science.gov (United States)

    Smith, Scott M.

    2002-01-01

    Space flight anemia is a widely recognized phenomenon in astronauts. Reduction in circulating red blood cells and plasma volume results in a 10% to 15% decrement in circulatory volume. This effect appears to be a normal physiologic adaptation to weightlessness and results from the removal of newly released blood cells from the circulation. Iron availability increases, and (in the few subjects studied) iron stores increase during long-duration space flight. The consequences of these changes are not fully understood.

  4. View of Arabella, one of two Skylab spiders and her web

    Science.gov (United States)

    1973-01-01

    A close-up view of Arabella, one of the two Skylab 3 common cross spiders 'aranous diadematus,' and the web it had spun in the zero gravity of space aboard the Skylab space station cluster in Earth orbit. During the 59 day Skylab 3 mission the two spiders Arabella and Anita, were housed in an enclosure onto which a motion picture and still camera were attached to record the spiders' attempts to build a web in the weightless environment.

  5. STS-40 Payload Specialist Millie Hughes-Fulford trains in JSC's SLS mockup

    Science.gov (United States)

    1987-01-01

    STS-40 Payload Specialist Millie Hughes-Fulford conducts Spacelab Life Sciences 1 (SLS-1) Experiment No. 198, Pulmonary Function During Weightlessness, in JSC's Life Sciences Project Division (LSPD) SLS mockup located in the Bioengineering and Test Support Facility Bldg 36. Hughes-Fulford monitors instruments and settings on Rack 8's panels. Behind her in the center aisle are the body mass measurement device (foreground) and the stowed bicycle ergometer.

  6. ESA MS Nicollier extends mockup tetherline prior to JSC WETF simulation

    Science.gov (United States)

    1987-01-01

    European Space Agency (ESA) Mission Specialist (MS) Claude Nicollier, turning a crank, extends a tetherline from a reel mounted on a mockup of the forward payload bay (PLB) bulkhead. Nicollier familiarizes himself with the operation of the safety tether system prior to donning an extravehicular mobility unit (EMU) and participating in an underwater extravehicular activity (EVA) simu- lation in JSC's Weightless Environment Training Facility (WETF) Bldg 29 pool.

  7. Experiment K-6-08. Biochemical and histochemical observations of vastus medialis

    Science.gov (United States)

    Musacchia, X. J.; Steffen, J. M.; Fell, R. D.; Oganov, V. S.

    1990-01-01

    Muscles of the hindlimb in the rat have been used to demonstrate the effects of unloading in weightlessness and in animal models used to mimic weightlessness. The vastus medialis (VM) is discussed here. Samples were obtained from rats exposed to weightlessness for 12 days in Cosmos 1887 (Experiment K-6-08, coordinated by Dr. V.S. Oganov). The principal objective of this study was to ascertain if the vastus medialis responded to 12 days of microgravity exposure. The loss in muscle mass is greatest, -43 percent, when comparing F vs B, and least, -13 percent, when comparing F vs. V. Taken at face value these differences may be misleading. Due to the variability of the muscle weight in the basal group, these muscle mass losses may be exaggerated. In terms of percent water, there were no differences between the flight and the control groups. In spite of the limited sample, researchers conclude that muscle mass changes in the VM are not significant. Although some of the morphological parameters suggest a small degree of atrophy in the vastus medialis, the biochemical analyses (protein, RNA and DNA) suggest that these may be minimal and functionally nonsignificant. The relatively similar CS and LDH activities of VM from F and various control groups, as well as the lack of difference in LPL activity between F and S rats, suggests that there is little or no effect on the oxidative or glycolytic function of this muscle. Since the VM is chiefly a mixed fast twitch muscle, these metabolic indices of energy production are relatively unchanged. The results of VM studies are in agreement with previous observations of another type II fast twitch muscle, the EDL, from SL-3 rats which did not respond markedly to weightlessness and whole body suspension.

  8. Newton in Space

    Science.gov (United States)

    Herbert, Dexter (Editor)

    1992-01-01

    In this 'Liftoff to Learning' series video, astronauts (Charles Veach, Gregory Harbaugh, Donald McMonagle, Michael Coats, L. Blaine Hammond, Guion Bluford, Richard Hieb) from the STS-39 Mission use physical experiments and computer animation to explain how weightlessness and gravity affects everything and everyone onboard the Space Shuttle. The physics behind the differences between weight and mass, and the concepts of 'free fall', are demonstrated along with explanations and experiments of Sir Issac Newton's three laws of motion.

  9. A long term model of circulation. [human body

    Science.gov (United States)

    White, R. J.

    1974-01-01

    A quantitative approach to modeling human physiological function, with a view toward ultimate application to long duration space flight experiments, was undertaken. Data was obtained on the effect of weightlessness on certain aspects of human physiological function during 1-3 month periods. Modifications in the Guyton model are reviewed. Design considerations for bilateral interface models are discussed. Construction of a functioning whole body model was studied, as well as the testing of the model versus available data.

  10. The control of calcium metabolism by parathyroid hormone, calcitonin and vitamin D

    Science.gov (United States)

    Potts, J. T., Jr.

    1976-01-01

    Advances in analysis of chemistry and physiology of parathyroid hormone, calcitonin, and Vitamin D are described along with development of techniques in radioassay methods. Emphasis is placed on assessment of normal and abnormal patterns of secretion of these hormones in specific relation to the physiological adaptations of weightlessness and space flight. Related diseases that involve perturbations in normal skeletal and calcium homeostasis are also considered.

  11. Balance Function Disorders

    Science.gov (United States)

    1991-01-01

    Researchers at the Balance Function Laboratory and Clinic at the Minneapolis (MN) Neuroscience Institute on the Abbot Northwestern Hospital Campus are using a rotational chair (technically a "sinusoidal harmonic acceleration system") originally developed by NASA to investigate vestibular (inner ear) function in weightlessness to diagnose and treat patients with balance function disorders. Manufactured by ICS Medical Corporation, Schaumberg, IL, the chair system turns a patient and monitors his or her responses to rotational stimulation.

  12. An Introduction to Surface-Free Behaviour

    Science.gov (United States)

    1964-01-01

    discussion. Les techniques d𔄀tude comprennent l’analyse physique des mouvements , la validation en vol de ces analyges et la projection math6matique de...for maintaining proper circulation during weightlessness. Les mouvements d’un sujet flottant librement en 6tat d’apesanteur sent l’objet de la...l’orbite probable des mouvements . On examine en outre les sensations que font, naitre ces mouvements . La liberti de mouvement d’un sujet sans contact avec

  13. Life science experiments during parabolic flight: The McGill experience

    Science.gov (United States)

    Watt, D. G. D.

    1988-01-01

    Over the past twelve years, members of the Aerospace Medical Research Unit of McGill University have carried out a wide variety of tests and experiments in the weightless condition created by parabolic flight. This paper discusses the pros and cons of that environment for the life scientist, and uses examples from the McGill program of the types of activities which can be carried out in a transport aircraft such as the NASA KC-135.

  14. [BEHAVIORAL AND FUNCTIONAL VESTIBULAR DISTURBANCES AFTER SPACE FLIGHT. 2. FISHES, AMPHIBIANS AND BIRDS].

    Science.gov (United States)

    Lychakov, D V

    2016-01-01

    The review contains data on functional shifts in fishes, amphibians and birds caused by changes in the otolith system operation after stay under weightlessness conditions. These data are of theoretical and practical significance and are important to resolve some fundamental problems of vestibulogy. The analysis of the results of space experiments has shown that weightlessness conditions do not exert a substantial impact on formation and functional state of the otolith system in embryonic fishes, amphibians and birds developed during space flight. Weightlessness conditions do pot inhibit embryonic development of lower vertebrates but even have rather beneficial effect on it. This is consistent with conclusions concerning development of mammalian fetuses. The experimental results show that weightlessness can cause similar functional and behavioral vestibular shifts both in lower vertebrates and in mammals. For example, immediately after an orbital flight the vestibuloocular reflex in fish larvae and tadpoles (without lordosis) was stronger than in control individuals. A similar shift of the otolith reflex was observed in the majority of cosmonauts after short-term orbital flights. Immediately after landing adult terrestrial vertebrates, as well as human beings, exhibit lower activity levels, worse equilibrium and coordination of movements. Another interesting finding observed after landing of the cosmic apparatus was an unusual looping character of tadpole swimming. It is supposed that the unusual motor activity of animals as well as appearance of illusions in cosmonauts and astronauts after switching from 1 to 0 g have the same nature and are related to the change in character of otolith organs stimulation. Considering this similarity of vestibular reactions, using animals seems rather perspective. Besides it allows applying in experiments various invasive techniques.

  15. [Analysis of possible causes activation a stomach and pancreas excretory and incretory function after completion of space flight on the international space station].

    Science.gov (United States)

    Afonin, B V

    2013-01-01

    The research excretory and incretory of activity of a stomach and pancreas is carried out at astronauts in the early period after completion of space flights of various duration. It is shown, that the increase of the contents of gastric and pancreatic enzymes and hormones (insulin and C-peptide) in blood reflects increased excretory and incretory activity of organs of gastroduodenal area which arises in weightlessness. The complex of countermeasures, which prevent ingress of subjects, infected by Helicobacter pylori in space flight crew, excluded participation of this microorganism in the mechanism of increase of secretory activity of a stomach. The absence of interrelation between increase of secretory activity of gastroduodenal area organs and space flights' duration has allowed to exclude the hypokinetic mechanism which determined by duration of stay in weightlessness. It was shown that after the end of space flights the increase ofbasal excretory activity of organs of gastroduodenal area occurs simultaneously with increase of a fasting insulin secretion. The changes in gastroduodenal area organs revealed after space flights were are compared to similar changes received in ground-based experiments, simulating hemodynamic reorganization in venous system of abdominal cavity, arising in weightlessness. The conclusion is made, that the basic mechanism of changes of a functional condition of digestive system in space flights, is determined by reorganization venous hemodynamic in abdominal cavity organs reproduced in ground experiments. Increase insulin and C-peptide after space flights are considered as hormonal component of this hemodynamic mechanism.

  16. Diamagnetic levitation enhances growth of liquid bacterial cultures by increasing oxygen availability.

    Science.gov (United States)

    Dijkstra, Camelia E; Larkin, Oliver J; Anthony, Paul; Davey, Michael R; Eaves, Laurence; Rees, Catherine E D; Hill, Richard J A

    2011-03-06

    Diamagnetic levitation is a technique that uses a strong, spatially varying magnetic field to reproduce aspects of weightlessness, on the Earth. We used a superconducting magnet to levitate growing bacterial cultures for up to 18 h, to determine the effect of diamagnetic levitation on all phases of the bacterial growth cycle. We find that diamagnetic levitation increases the rate of population growth in a liquid culture and reduces the sedimentation rate of the cells. Further experiments and microarray gene analysis show that the increase in growth rate is owing to enhanced oxygen availability. We also demonstrate that the magnetic field that levitates the cells also induces convective stirring in the liquid. We present a simple theoretical model, showing how the paramagnetic force on dissolved oxygen can cause convection during the aerobic phases of bacterial growth. We propose that this convection enhances oxygen availability by transporting oxygen around the liquid culture. Since this process results from the strong magnetic field, it is not present in other weightless environments, e.g. in Earth orbit. Hence, these results are of significance and timely to researchers considering the use of diamagnetic levitation to explore effects of weightlessness on living organisms and on physical phenomena.

  17. Left ventricular remodeling during and after 60 days of sedentary head-down bed rest.

    Science.gov (United States)

    Westby, Christian M; Martin, David S; Lee, Stuart M C; Stenger, Michael B; Platts, Steven H

    2016-04-15

    Short periods of weightlessness are associated with reduced stroke volume and left ventricular (LV) mass that appear rapidly and are thought to be largely dependent on plasma volume. The magnitude of these cardiac adaptations are even greater after prolonged periods of simulated weightlessness, but the time course during and the recovery from bed rest has not been previously described. We collected serial measures of plasma volume (PV, carbon monoxide rebreathing) and LV structure and function [tissue Doppler imaging, three-dimensional (3-D) and 2-D echocardiography] before, during, and up to 2 wk after 60 days of 6° head down tilt bed rest (HDTBR) in seven healthy subjects (four men, three women). By 60 days of HDTBR, PV was markedly reduced (2.7 ± 0.3 vs. 2.3 ± 0.3 liters,PResting measures of LV volume and mass were ∼15% (Prest values (P< 0.001). As previously reported, decreased PV and LV volume precede and likely contribute to cardiac atrophy during prolonged LV unloading. Although PV and LV volume recover rapidly after HDTBR, there is no concomitant normalization of LV mass. These results demonstrate that reduced LV mass in response to prolonged simulated weightlessness is not a simple effect of tissue dehydration, but rather true LV muscle atrophy that persists well into recovery.

  18. Fluid and Electrolyte Balance and Kidney Function Research in Space

    Science.gov (United States)

    Norsk, P.; Juel, N.; Kramer, H. J.; de Santo, N. G.; Regnard, J.; Heer, M.

    2005-06-01

    Fluid and electrolyte regulation in humans is modulated by gravitational stress through a complex interaction of cardiovascular reflexes, neuroendocrine variables, physical factors and renal function.Weightlessness is a unique tool to obtain more information on integrated fluid volume control. Results from space, however, have been unexpected and unpredictable from the results of ground- based simulations.The concept of how weightlesness and gravity modulate the regulation of body fluids and associated blood components must therefore be revised and a new simulation model developed. There are several main questions to be asked. Does weightlessness induce diuresis and natriuresis during the initial hours of spaceflight, leading to an extracellular and intravascular fluid volume deficit? Why are fluid- and sodium-retaining systems activated by spaceflight, and why are the renal responses to saline and water stimuli attenuated? Can excess sodium be stored in an hitherto unknown way, in particular during spaceflight? How can the effects of weightlessness on fluid and electrolyte regulation be correctly simulated on the ground? The information obtained from space might help us to understand how gravity degrades the fluid and electrolyte balance in sodium-retaining and oedema- forming states, such as in heart failure.

  19. Medical considerations for extending human presence in space

    Science.gov (United States)

    Leach, C. S.; Dietlein, L. F.; Pool, S. L.; Nicogossian, A. E.

    The prospects for extending the length of time that humans can safely remain in space depend partly on resolution of a number of medical issues. Physiologic effects of weightlessness that may affect health during flight include loss of body fluid, functional alterations in the cardiovascular system, loss of red blood cells and bone mineral, compromised immune system function, and neurosensory disturbances. Some of the physiologic adaptations to weightlessness contribute to difficulties with readaptation to Earth's gravity. These include cardiovascular deconditioning and loss of body fluids and electrolytes; red blood cell mass; muscle mass, strength, and endurance; and bone mineral. Potentially harmful factors in space flight that are not related to weightlessness include radiation, altered circadian rhythms and rest/work cycles, and the closed, isolated environment of the spacecraft. There is no evidence that space flight has long-term effects on humans, except that bone mass lost during flight may not be replaced, and radiation damage is cumulative. However, the number of people who have spent several months or longer in space is still small. Only carefully-planned experiments in space preceded by thorough ground-based studies can provide the information needed to increase the amount of time humans can safely spend in space.

  20. From Milk to Bones, Moving Calcium Through the Body: Calcium Kinetics During Space Flight

    Science.gov (United States)

    Smith, Scott; Bloomberg, Jacob; Lee, Angie (Technical Monitor)

    2002-01-01

    Did you know that when astronauts are in space, their height increases about two inches? This happens because the weightlessness of space allows the spine, usually compressed in Earth's gravity, to expand. While this change is relatively harmless, other more serious things can happen with extended stays in weightlessness, notably bone loss. From previous experiments, scientists have observed that astronauts lose bone mass at a rate of about one percent per month during flight. Scientists know that bone is a dynamic tissue - continually being made and repaired by specialized bone cells throughout life. Certain cells produce new bone, while other cells are responsible for removing and replacing old bone. Research on the mechanisms of bone metabolism and the effects of space flight on its formation and repair are part of the exciting studies that will be performed during STS-107. Calcium plays a central role because 1) it gives strength and structure to bone and 2) all types of cells require it to function normally. Ninety-nine percent of calcium in the body is stored in the skeleton. However, calcium may be released, or resorbed, from bone to provide for other tissues when you are not eating. To better understand how and why weightlessness induces bone loss, astronauts will participate in a study of calcium kinetics - that is, the movement of calcium through the body, including absorption from food, and its role in the formation and breakdown of bone.

  1. [Reduction of dielectric properties of rat gastrocnemius induced by loss of weight].

    Science.gov (United States)

    Tang, Zhiynan; Zhao, Weihong; Wang, Lin; Ma, Qing

    2009-10-01

    In this experimental study, the AC impedance of isolated gastrocnemius was measured with an impendance analyzer of Agilent 4294A, and the effect of simulated weightlessness on the dielectric properties of the cells in isolated rat sural muscle was investigated by analyzing the dielectric numerical characters with the use of dielectric spectroscopy, the Cole-Cole plots, the spectrum of loss factor and loss tangent, as well as the spectrum of conductivity imaginary part. The results demonstrated that 10 weeks' simulated weightlessness caused some changes; for example, both permittivity at low frequency (epsilonL) and permittivity increment (deltaepsilon) were reduced, and conductivity at high frequency (kappa(h)) was also reduced; at the same time, conductivity increment (deltakappa) was reduced, too. The first characteristic frequency (f(C1)) decreased, while the second characteristic frequency(f(C2)) increased. All of the peak of loss factor, the peak of loss tangent, and the maximum of conductivity imaginary part were reduced. These data indicated that the reduction of dielectric properties of skeletal muscles was induced by weightlessness.

  2. Morphological analysis of Japanese quail embryos developed onboard orbital station "Mir" during NASA-"Mir" research program experiments (1990-1996)

    Science.gov (United States)

    Gusev, O.; Gyrieva, T.; Dadasheva, O.; Pahomov, A.; Pirt, C.

    From 1990 to 1996, 5 experiments onboard "MIR" space station which allowed to receive important data dynamics of embryonic development of birds in micro gravitational conditions was carried out by NASA-"MIR" research program, using fertilized eggs of Japanese quail, as convenient object for space experiments. Here we represent the comparative morphomethrical analysis of incubation modes influence on a morphogenesis of Japanese quail. The data allowed us to make the conclusion that the embryonic development of Japanese quail in weightlessness conditions results in authentic decrease of length and body mass parameters in comparison with the embryos, developed in the ground laboratory conditions. The development of a skeleton and extremities, in general developing in normal way, demonstrates decreasing of legs length (10-12%) and body mass (8-12%), but there are no differences in wings length. At the same time we didn't find any significant differences in extremities length in laboratory and synchronic experimental groups of embryos. Analysis didn't show any significant influence of location of eggs in the incubator on mortality of the embryos. The main results of experiments have shown presence of morphometrical changes connected first of all with presence of weightlessness in the surrounded environment. In general, the data a alysis oncen again confirms the assumption that the changed gravity is not an interrupt factor for development of Japanese quail nestlings from fertilized eggs, but further experiments are required for detailed understanding of weightless influence on birds development.

  3. Analysis of magnetic gradients to study gravitropism.

    Science.gov (United States)

    Hasenstein, Karl H; John, Susan; Scherp, Peter; Povinelli, Daniel; Mopper, Susan

    2013-01-01

    Gravitropism typically is generated by dense particles that respond to gravity. Experimental stimulation by high-gradient magnetic fields provides a new approach to selectively manipulate the gravisensing system. The movement of corn, wheat, and potato starch grains in suspension was examined with videomicroscopy during parabolic flights that generated 20 to 25 s of weightlessness. During weightlessness, a magnetic gradient was generated by inserting a wedge into a uniform, external magnetic field that caused repulsion of starch grains. The resultant velocity of movement was compared with the velocity of sedimentation under 1 g conditions. The high-gradient magnetic fields repelled the starch grains and generated a force of at least 0.6 g. Different wedge shapes significantly affected starch velocity and directionality of movement. Magnetic gradients are able to move diamagnetic compounds under weightless or microgravity conditions and serve as directional stimulus during seed germination in low-gravity environments. Further work can determine whether gravity sensing is based on force or contact between amyloplasts and statocyte membrane system.

  4. Research progress in the effect of mechanical vibration on the prevention and treatment of osteoporosis%机械振动防治失重性骨质疏松的研究进展

    Institute of Scientific and Technical Information of China (English)

    陶飞飞; 吴继功

    2014-01-01

    随着载人空间站发展,在军事和民用都有着巨大应用价值,载人航天器围绕地球旋转时,由于离心力与重力相平衡,理论上其内部为零重力,这称之为失重。对于失重下的减少骨量丢失,药物预防或者治疗尚未达到理想的效果,并不能阻止失重状态下骨量的丢失,目前的研究证明了采用机械振动的方法可能是一种有效防治失重性骨质疏松的措施。因此本文对机械振动在动物、细胞、临床方面的研究现状以及防治失重性骨质疏松方面的临床应用前景进行综述。%With the development of manned space station, it has a huge value in both military and civilian application.When the manned spacecraft rotates around the earth, because of the equilibrium between the centrifugal force and the gravity, in theory, its internal gravity is zero, which is called weightlessness.For the bone loss under weightlessness, the drug prevention or treatment has not yet reached the ideal result, and it bone mass loss cannot be prevented under the state of weightlessness.The recent research proves that mechanical vibration may be an effective method for the prevention and treatment of bone mass loss under the state of weightlessness.This article reviews the current research of the mechanical vibration on animals, cells, and clinical aspects and the prospect of its clinical application on the prevention and treatment of osteoporosis under the state of weightlessness.

  5. Microgravity and bone cell mechanosensitivity

    Science.gov (United States)

    Klein-Nulend, J.; Bacabac, R. G.; Veldhuijzen, J. P.; Van Loon, J. J. W. A.

    2003-10-01

    The capacity of bone tissue to alter its mass and structure in response to mechanical demands has long been recognized but the cellular mechanisms involved remained poorly understood. Bone not only develops as a structure designed specifically for mechanical tasks, but it can adapt during life toward more efficient mechanical performance. Mechanical adaptation of bone is a cellular process and needs a biological system that senses the mechanical loading. The loading information must then be communicated to the effector cells that form new bone or destroy old bone. The in vivo operating cell stress derived from bone loading is likely the flow of interstitial fluid along the surface of osteocytes and lining cells. The response of bone cells in culture to fluid flow includes prostaglandin (PG) synthesis and expression of prostaglandin G/H synthase inducible cyclooxygenase (COX-2). Cultured bone cells also rapidly produce nitric oxide (NO) in response to fluid flow as a result of activation of endothelial nitric oxide synthase (ecNOS), which enzyme also mediates the adaptive response of bone tissue to mechanical loading. Earlier studies have shown that the disruption of the actin-cytoskeleton abolishes the response to stress, suggesting that the cytoskeleton is involved in cellular mechanotransduction. Microgravity, or better near weightlessness, is associated with the loss of bone in astronauts, and has catabolic effects on mineral metabolism in bone organ cultures. This might be explained as resulting from an exceptional form of disuse under near weightlessness conditions. However, under near weightlessness conditions the assembly of cytoskeletal elements may be altered since it has been shown that the direction of the gravity vector determines microtubular pattern formation in vivo. We found earlier that the transduction of mechanical signals in bone cells also involves the cytoskeleton and is related to PGEZ production. Therefore it is possible that the

  6. 抗磁性物质磁悬浮方法在空间生物学与生物技术中的应用%Application of Magnetic Levitation of Diamagnetic Materials for Space Biology and Biotechnology

    Institute of Scientific and Technical Information of China (English)

    曹建平; 尹大川; 骞爱荣; 田宗成; 续惠云; 黄勇平; 商澎

    2011-01-01

    Weightlessness is one of the important physical characteristics of space environment. For several decades, weightless environment in space has been used for investigation and exploration in many scientific fields. Because of shortage and limit of experiments in real space environment, many kinds of ground-based simulated techniques and methods inspired by space experimental environments were developed for simulating the weightlessness of space environment and the effects of weightlessness. However, these techniques and methods have limitations not only in principle, but also in application for space biology and biotechnology. In this paper, we introduced a new technique for simulating weightlessness, magnetic levitation of diamagnetic materials produced by large gradlient high magnetic field, and summarized the research progress by using this technique in crystal growth of proteins, molecular cell biology and integrated biology.%失重是特定空间运动条件下的重要环境物理特征之一,一般以微重力环境来表示.几十年来人类利用空间失重环境进行了多学科领域的科学研究与探索.由于真实空间失重环境下科学实验机会稀少,人类为研究空间失重环境或效应,开发了多种地基的空间模拟实验技术方法.然而,对于空间生物学和空间生物技术研究而言,已有的各种模拟实验技术手段在原理上和应用上均存在一定的局限性.本文介绍了抗磁性物质在大梯度强磁场中的悬浮现象,及将其用于模拟空间失重环境的方法与原理;简述了近年来利用抗磁性物质悬浮方法进行生物大分子晶体生长、分子细胞生物学及整体生物学等方面研究与应用的进展.

  7. Regulation of body fluid volume and electrolyte concentrations in spaceflight

    Science.gov (United States)

    Smith, S. M.; Krauhs, J. M.; Leach, C. S.

    1997-01-01

    Despite a number of difficulties in performing experiments during weightlessness, a great deal of information has been obtained concerning the effects of spaceflight on the regulation of body fluid and electrolytes. Many paradoxes and questions remain, however. Although body mass, extracellular fluid volume, and plasma volume are reduced during spaceflight and remain so at landing, the changes in total body water are comparatively small. Serum or plasma sodium and osmolality have generally been unchanged or reduced during the spaceflight, and fluid intake is substantially reduced, especially during the first of flight. The diuresis that was predicted to be caused by weightlessness, has only rarely been observed as an increased urine volume. What has been well established by now, is the occurrence of a relative diuresis, where fluid intake decreases more than urine volume does. Urinary excretion of electrolytes has been variable during spaceflight, but retention of fluid and electrolytes at landing has been consistently observed. The glomerular filtration rate was significantly elevated during the SLS missions, and water and electrolyte loading tests have indicated that renal function is altered during readaptation to Earth's gravity. Endocrine control of fluid volumes and electrolyte concentrations may be altered during weightlessness, but levels of hormones in body fluids do not conform to predictions based on early hypotheses. Antidiuretic hormone is not suppressed, though its level is highly variable and its secretion may be affected by space motion sickness and environmental factors. Plasma renin activity and aldosterone are generally elevated at landing, consistent with sodium retention, but inflight levels have been variable. Salt intake may be an important factor influencing the levels of these hormones. The circadian rhythm of cortisol has undoubtedly contributed to its variability, and little is known yet about the influence of spaceflight on circadian

  8. Biomechanics of the Treadmill Locomotion on the International Space Station

    Science.gov (United States)

    DeWitt, John; Cromwell, R. L.; Ploutz-Snyder, L. L.

    2014-01-01

    Exercise prescriptions completed by International Space Station (ISS) crewmembers are typically based upon evidence obtained during ground-based investigations, with the assumption that the results of long-term training in weightlessness will be similar to that attained in normal gravity. Coupled with this supposition are the assumptions that exercise motions and external loading are also similar between gravitational environments. Normal control of locomotion is dependent upon learning patterns of muscular activation and requires continual monitoring of internal and external sensory input [1]. Internal sensory input includes signals that may be dependent on or independent of gravity. Bernstein hypothesized that movement strategy planning and execution must include the consideration of segmental weights and inertia [2]. Studies of arm movements in microgravity showed that individuals tend to make errors but that compensation strategies result in adaptations, suggesting that control mechanisms must include peripheral information [3-5]. To date, however, there have been no studies examining a gross motor activity such as running in weightlessness other than using microgravity analogs [6-8]. The objective of this evaluation was to collect biomechanical data from crewmembers during treadmill exercise before and during flight. The goal was to determine locomotive biomechanics similarities and differences between normal and weightless environments. The data will be used to optimize future exercise prescriptions. This project addresses the Critical Path Roadmap risks 1 (Accelerated Bone Loss and Fracture Risk) and 11 (Reduced Muscle Mass, Strength, and Endurance). Data were collected from 7 crewmembers before flight and during their ISS missions. Before launch, crewmembers performed a single data collection session at the NASA Johnson Space Center. Three-dimensional motion capture data were collected for 30 s at speeds ranging from 1.5 to 9.5 mph in 0.5 mph increments

  9. Catecholamines and their enzymes in discrete brain areas of rats after space flight on biosatellites Cosmos.

    Science.gov (United States)

    Kvetnansky, R; Culman, J; Serova, L V; Tigranjan, R A; Torda, T; Macho, L

    1983-01-01

    The activity of the catecholaminergic system was measured in the hypothalamus of rats which had experienced an 18.5-19.5-day-long stay in the state of weightlessness during space flights on board Soviet biosatellites of the type Cosmos. In the first two experiments, Cosmos 782 and 936, the concentration of norepinephrine and the activities of synthesizing enzymes tyrosine hydroxylase and dopamine-beta-hydroxylase and of the degrading enzyme monoamine oxidase were measured in the total hypothalamus. None of the given parameters was changed after space flight. In the light of the changes of these parameters recorded after exposure to acute stress on Earth, this finding indicates that long-term state of weightlessness does not represent an intensive stressogenic stimulus for the system studied. In the space experiment Cosmos 1129, the concentration of norepinephrine, epinephrine, and dopamine was studied in isolated nuclei of the hypothalamus of rats within 6-10 hr following return from space. Norepinephrine was found to be significantly reduced in the arcuate nucleus, median eminence and periventricular nucleus, epinephrine in the median eminence, periventricular and suprachiasmatic nuclei, whereas dopamine was not significantly changed after space flight. The decreased catecholamine levels found in some hypothalamic nuclei of rats which had undergone space flight indicate that no chronic intensive stressor could have acted during the flight, otherwise the catecholamine concentration would have been increased in the nuclei. The decreased levels must have been induced by the effect of a stressogenic factor acting for a short time only, and that either during the landing maneuver or immediately after landing. Thus long-term exposure of the organism to the state of weightlessness does not represent a stressogenic stimulus for the catecholaminergic system in the hypothalamus, which is one of the regulators of the activation of neuroendocrine reactions under stress.

  10. A comprehensive Guyton model analysis of physiologic responses to preadapting the blood volume as a countermeasure to fluid shifts

    Science.gov (United States)

    Simanonok, K. E.; Srinivasan, R. S.; Myrick, E. E.; Blomkalns, A. L.; Charles, J. B.

    1994-01-01

    The Guyton model of fluid, electrolyte, and circulatory regulation is an extensive mathematical model capable of simulating a variety of experimental conditions. It has been modified for use at NASA to simulate head-down tilt, a frequently used analog of weightlessness. Weightlessness causes a headward shift of body fluids that is believed to expand central blood volume, triggering a series of physiologic responses resulting in large losses of body fluids. We used the modified Guyton model to test the hypothesis that preadaptation of the blood volume before weightless exposure could counteract the central volume expansion caused by fluid shifts, and thereby attenuate the circulatory and renal responses that result in body fluid losses. Simulation results show that circulatory preadaptation, by a procedure resembling blood donation immediately before head-down bedrest, is effective in damping the physiologic responses to fluid shifts and reducing body fluid losses. After 10 hours of head-down tilt, preadaptation also produces higher blood volume, extracellular volume, and total body water for 20 to 30 days of bedrest, compared with non-preadapted control. These results indicate that circulatory preadaptation before current Space Shuttle missions may be beneficial for the maintenance of reentry and postflight orthostatic tolerance in astronauts. This paper presents a comprehensive examination of the simulation results pertaining to changes in relevant physiologic variables produced by blood volume reduction before a prolonged head-down tilt. The objectives were to study and develop the countermeasure theoretically, to aid in planning experimental studies of the countermeasure, and to identify potentially disadvantageous physiologic responses that may be caused by the countermeasure.

  11. Microgravity-induced alterations in signal transduction in cells of the immune system

    Science.gov (United States)

    Paulsen, Katrin; Thiel, Cora; Timm, Johanna; Schmidt, Peter M.; Huber, Kathrin; Tauber, Svantje; Hemmersbach, Ruth; Seibt, Dieter; Kroll, Hartmut; Grote, Karl-Heinrich; Zipp, Frauke; Schneider-Stock, Regine; Cogoli, Augusto; Hilliger, Andre; Engelmann, Frank; Ullrich, Oliver

    2010-11-01

    Since decades it is known that the activity of cells of the immune system is severely dysregulated in microgravity, however, the underlying molecular aspects have not been elucidated yet. The identification of gravity-sensitive molecular mechanisms in cells of the immune system is an important and indispensable prerequisite for the development of counteractive measures to prevent or treat disturbed immune cell function of astronauts during long-term space missions. Moreover, their sensitivity to altered gravity renders immune cells an ideal model system to understand if and how gravity on Earth is required for normal mammalian cell function and signal transduction. We investigated the effect of simulated weightlessness (2D clinostat) and of real microgravity (parabolic flights) on key signal pathways in a human monocytic and a T lymphocyte cell line. We found that cellular responses to microgravity strongly depend on the cell-type and the conditions in which the cells are subjected to microgravity. In Jurkat T cells, enhanced phosphorylation of the MAP kinases ERK-1/2, MEK and p38 and inhibition of nuclear translocation of NF-kB were the predominant responses to simulated weightlessness, in either stimulated or non-stimulated cells. In contrast, non-stimulated monocytic U937 cells responded to simulated weightlessness with enhanced overall tyrosine-phosphorylation and activation of c-jun, whereas PMA-stimulated U937 cells responded the opposite way with reduced tyrosine-phosphorylation and reduced activation of c-jun, compared with PMA-stimulated 1 g controls. P53 protein was phosphorylated rapidly in microgravity. The identification of gravi-sensitive mechanisms in cells of the immune system will not only enable us to understand and prevent the negative effects of long time exposure to microgravity on Astronauts, but could also lead to novel therapeutic targets in general.

  12. A comprehensive Guyton model analysis of physiologic responses to preadapting the blood volume as a countermeasure to fluid shifts

    Science.gov (United States)

    Simanonok, K. E.; Srinivasan, R. S.; Myrick, E. E.; Blomkalns, A. L.; Charles, J. B.

    1994-01-01

    The Guyton model of fluid, electrolyte, and circulatory regulation is an extensive mathematical model capable of simulating a variety of experimental conditions. It has been modified for use at NASA to simulate head-down tilt, a frequently used analog of weightlessness. Weightlessness causes a headward shift of body fluids that is believed to expand central blood volume, triggering a series of physiologic responses resulting in large losses of body fluids. We used the modified Guyton model to test the hypothesis that preadaptation of the blood volume before weightless exposure could counteract the central volume expansion caused by fluid shifts, and thereby attenuate the circulatory and renal responses that result in body fluid losses. Simulation results show that circulatory preadaptation, by a procedure resembling blood donation immediately before head-down bedrest, is effective in damping the physiologic responses to fluid shifts and reducing body fluid losses. After 10 hours of head-down tilt, preadaptation also produces higher blood volume, extracellular volume, and total body water for 20 to 30 days of bedrest, compared with non-preadapted control. These results indicate that circulatory preadaptation before current Space Shuttle missions may be beneficial for the maintenance of reentry and postflight orthostatic tolerance in astronauts. This paper presents a comprehensive examination of the simulation results pertaining to changes in relevant physiologic variables produced by blood volume reduction before a prolonged head-down tilt. The objectives were to study and develop the countermeasure theoretically, to aid in planning experimental studies of the countermeasure, and to identify potentially disadvantageous physiologic responses that may be caused by the countermeasure.

  13. Increased brain cortical activity during parabolic flights has no influence on a motor tracking task.

    Science.gov (United States)

    Schneider, Stefan; Brümmer, Vera; Mierau, Andreas; Carnahan, Heather; Dubrowski, Adam; Strüder, Heiko K

    2008-03-01

    Previous studies showed that changing forces of gravity as they typically occur during parabolic flights might be responsible for adaptional processes of the CNS. However, until now it has not been differentiated between primary influences of weightlessness and secondary influences due to psycho-physiological factors (e.g., physical or mental strain). With the aim of detecting parabolic flight related changes in central cortical activity, a resting EEG was deduced in 16 subjects before, during and after parabolic flights. After subdividing EEG into alpha-, beta-,delta- and theta-wave bands, an increase in beta-power was noticeable inflight, whereas alpha(1)-power was increased postflight. No changes could be observed for the control group. To control possible effects of cortical activation, a manual tracking task with mirror inversion was performed during either the phase of weightlessness or during the normal gravity phase of a parabolic flight. No differences in performance nor in adaptation could be observed between both groups. A third group, performing under normal and stress-free conditions in a lab showed similar tracking values. We assume that the specific increase in brain activity is a sign of an increase in arousal inflight. This does support previous assumptions of non-specific stressors during parabolic flights and has to be considered as a relevant factor for experiments on central nerve adaptation. Although no influences of stress and/or weightlessness on motor performance and adaptation could be observed, we suggest that an "inflight" control group seems to be more adequate than a laboratory control group to investigate gravity-dependent changes in motor control.

  14. Progress on Concepts for Next-Generation Drop Tower Systems

    Science.gov (United States)

    Könemann, Thorben; Eigenbrod, Christian; Von Kampen, Peter; Laemmerzahl, Claus; Kaczmarczik, Ulrich

    2016-07-01

    The Center of Applied Space Technology and Microgravity (ZARM) founded by Prof. Dr.-Ing. Hans J. Rath in 1985 is part of the Department of Production Engineering at the University of Bremen, Germany. ZARM is mainly concentrated on fundamental investigations of gravitational and space-related phenomenas under conditions of weightlessness as well as questions and developments related to technologies for space. At ZARM about 100 scientists, engineers, and administrative staff as well as many students from different departments are employed. Today, ZARM is still one of the largest and most important research center for space sciences and technologies in Europe. With a height of 146 m the Bremen Drop Tower is the predominant facility of ZARM and also the only drop tower of its class in Europe. ZARM's ground-based laboratory offers the opportunity for daily short-term experiments under conditions of high-quality weightlessness at a level of 10-6 g (microgravity), which is one of the best achievable for ground-based flight opportunities. Scientists may choose up to three times a day between a single drop experiment with 4.74 s in simple free fall and an experiment in ZARM's worldwide unique catapult system with 9.3 s in weightlessness. Since the start of operation of the facility in 1990, over 7500 drops or catapult launches of more than 160 different experiment types from various scientific fields like fundamental physics, combustion, fluid dynamics, planetary formation / astrophysics, biology and materials sciences have been accomplished so far. In addition, more and more technology tests have been conducted under microgravity conditions at the Bremen Drop Tower in order to effectively prepare appropriate space missions in advance. In this paper we report on the progress on concepts for next-generation drop tower systems based on the GraviTower idea utilizing a guided electro-magnetic linear drive. Alternative concepts motivated by the scientific demand for higher

  15. STS-34 Mission Specialists Chang-Diaz and Baker with EVA tools

    Science.gov (United States)

    1989-01-01

    STS-34 Atlantis, Orbiter Vehicle (OV) 104, Mission Specialist (MS) Franklin R. Chang-Diaz (center) and MS Ellen S. Baker (right) examine extravehicular activity (EVA) tools along with Rockwell Space Operations (RSO) technician Wayne J. Wedlake prior EVA contingency exercise (underwater simulation) in JSC's Weightless Environment Training Facility (WETF) Bldg 29. Chang-Diaz and Baker will practice using the EVA tools and rehearse chores which would require manual action outside the spacecraft in the event of failure of remote systems in the WETF's 25 ft pool.

  16. The Use of Drama in Science Education: The Case of ``Blegdamsvej Faust''

    Science.gov (United States)

    Pantidos, Panagiotis; Spathi, Kalliopi; Vitoratos, Evagelos

    This is a study of the structure of The Blegdamsvej Faust and its relation to Goethe's classical play Faust. The Blegdamsvej Faust, a play written and performed by Bohr's students in 1932, is inspired by the very rapid development of Physics in those turbulent years. A struggle is made to promote the odd idea of a weightless particle. Moreover, this study lays emphasis on the fact that new ideas of Physical Sciences become more accessible, comprehensible and familiar through dramatization. For scenario-vehicles one may use as a basis plays from the classical repertoire or write something new. Several hints are given in this article.

  17. Toys in Space, 2

    Science.gov (United States)

    Herbert, Dexter (Editor)

    1993-01-01

    In this educational video from the 'Liftoff to Learning' series, astronauts from the STS-54 Mission (Mario Runco, John Casper, Don McMonagle, Susan Helms, and Greg Harbaugh) explain how microgravity and weightlessness in space affects motion by using both mechanical and nonmechanical toys (gravitrons, slinkys, dart boards, magnetic marbles, and others). The gravitational effects on rotation, force, acceleration, magnetism, magnetic fields, center of axis, and velocity are actively demonstrated using these toys through experiments onboard the STS-54 Mission flight as a part of their spaceborne experiment payload. [Resource Guide referenced in the video is not available.

  18. EPM - The European Facility for human physiology research on ISS.

    Science.gov (United States)

    Rieschel, Mats; Nasca, Rosario; Junk, Peter; Gerhard, Ingo

    2002-07-01

    The European Physiology Modules (EPM) Facility is one of the four major Space Station facilities being developed within the framework of ESA's Microgravity Facilities for Columbus (MFC) programme. In order to allow a wide spectrum of physiological studies in weightlessness conditions, the facility provides the infrastructure to accommodate a variable set of scientific equipment. The initial EPM configuration supports experiments in the fields of neuroscience, bone & muscle research, cardiovascular research and metabolism. The International Space Life Science Working Group (ISLSWG) has recommended co-locating EPM with the 2 NASA Human Research Facility racks.

  19. Observation of arterial blood pressure of the primate

    Science.gov (United States)

    Meehan, J. P.; Henry, J. P.

    1973-01-01

    The developments are reported in physiological instrumentation, surgical procedures, measurement and data analysis techniques, and the definition of flight experiments to determine the effects of prolonged weightlessness on the cardiovascular system of subhuman primates. The development of an implantable telemetric data acquisition system is discussed along with cardiovascular research applications in renal hemodynamics. It is concluded that the implant technique permits a valid interpretation, free of emotional response, for the manipulated variable on physiological functions. It also allows a better definition of normal physiological baseline conditions.

  20. Biotechnologische Nutzung der Schwerelosigkeit für medizinische Forschung - Analyse humaner Zellen nach Schwerelosigkeit

    DEFF Research Database (Denmark)

    Grimm, Daniela Gabriele; Bauer, Johann; Hemmersbach, Ruth

    2013-01-01

    For periods of time ranging from 22 seconds in parabolic flights and up to two weeks on sattilites, human cells were exposed to real or simulated weightlessness on a Random Positioning Machine and a 2D clinostat and analysed afterwards. By this approach we can increase our knowledge regarding...... health problems of space travellers and in parallel we get new information concerning several diseases of humans on Earth. Surprisingly, we also observed that single cells exposed to simulated microgravity assemble to three-dimensional aggregates resembling the tissues from which these cells...

  1. Microgravity Experiment Programs for Students at the Bremen Drop Tower

    Science.gov (United States)

    Könemann, Thorben; Eigenbrod, Christian; Von Kampen, Peter; Laemmerzahl, Claus

    The Center of Applied Space Technology and Microgravity (ZARM) founded by Prof. Dr.-Ing. Hans J. Rath in 1985 is part of the Department of Production Engineering at the University of Bremen, Germany. ZARM established as a research center and currently headed by Prof. Dr. Claus Lämmerzahl is mainly concentrated on fundamental investigations of gravitational and space-related phenomenas under conditions of weightlessness as well as questions and developments related to technologies for space. At ZARM more than 70 scientists, engineers and administrative staff as well as many students from different departments are employed. Today, ZARM is still one of the largest and most important university institutes for space sciences and technologies in Europe as well as worldwide well known in the space community. With a height of 146 m the Bremen Drop Tower is the predominant facility of ZARM and also the only drop tower of its class in Europe. ZARM’s ground-based laboratory offers the opportunity for daily short-term experiments under conditions of high-quality weightlessness at a level of 10 (-6) g (microgravity). The provided quality is one of the purest for experiments under weightlessness worldwide achieved. The scientists may choose between a single drop experiment with 4.74 s in simple free fall and a catapult experiment with 9.3 s of weightlessness. Either in the drop or in the worldwide unique catapult operation routine the repetition rates of microgravity experiments at ZARM are always the same, generally up to 3 times per day. Since the start of operation of the facility in 1990, over 6750 launches of more than 160 different experiment types from various scientific fields like Fundamental Physics, Combustion, Fluid Dynamics, Planetary Formation / Astrophysics, Biology and Materials Sciences have been successfully accomplished so far. In our paper we will report and inform about microgravity experiment programs for students like „Drop Your Thesis!“ by ESA and

  2. Simulating certain aspects of hypogravity: Effects on the mandibular incisors of suspended rats (PULEH model)

    Science.gov (United States)

    Simmons, D. J.; Winter, F.; Morey-Holton, E. R.

    1984-01-01

    The effect of a hypogravity simulating model on the rate of mandibular incisor formation, dentinogenesis and, amelogenesis in laboratory rats was studied. The model is the partial unloading by elevating the hindquarters. In this system, rat hindquarters are elevated 30 to 40 deg from the cage floors to completely unload the hindlimbs, but the animals are free to move about using their forelimbs. This model replicates the fluid sift changes which occur during the weightlessness of spaceflight and produces an osteopenia in the weight bearing skeletons. The histogenesis and/or mineralization rates of the mandibular incisor during the first 19d of PULEH in young growing rats are recorded.

  3. Impact of floats on water

    CERN Document Server

    de Divitiis, Nicola; 10.1017/S002211200200229X

    2009-01-01

    The impact of a wedge-shaped body on the free surface of a weightless inviscid incompressible liquid is considered. Both symmetrical and unsymmetrical entries at constant velocity are dealt with. The differential problem corresponds to the physico-mathematical model of a distribution of potential singularities and, in particular, the flow singularities at the ends of the wetted regions are represented by sinks. A conformal transformation of the flow field is adopted and the unknown intensities of the discontinuities are found by an optimization procedure, together with the solution of the nonlinear free-surface problem. The flow separation at a sideslip is also considered.

  4. Long-term space flights - personal impressions

    Science.gov (United States)

    Polyakov, V. V.

    During a final 4-month stage of a 1-year space flight of cosmonauts Titov and Manarov, a physician, Valery Polyakov was included on a crew for the purpose of evaluating their health, correcting physical status to prepare for the spacecraft reentry and landing operations. The complex program of scientific investigations and experiments performed by the physician included an evaluation of adaptation reactions of the human body at different stages of space mission using clinicophysiological and biochemical methods; testing of alternative regimes of exercise and new countermeasures to prevent an unfavourable effect of long-term weightlessness.

  5. Artificial Gravity

    CERN Document Server

    Clément, Gilles

    2007-01-01

    Protecting the health, safety, and performance of exploration-class mission crews against the physiological deconditioning resulting from long-term weightlessness during transit and long-term reduced gravity during surface operations will require effective, multi-system countermeasures. Artificial gravity, which would replace terrestrial gravity with inertial forces generated by rotating the transit vehicle or by short-radius human centrifuge devices within the transit vehicle or surface habitat, has long been considered a potential solution. However, despite its attractiveness as an efficient

  6. Alterations in Signal Transduction and Intracellular Signaling Processes during Simulated Microgravity

    Science.gov (United States)

    Agarwal, Rakhee; Khan, Junaid; Laska, Bozena; Mehta, Rahul; Chowdhury, Parimal; Ali, Nawab

    2010-04-01

    A modified NASA validated tail suspension animal model of simulated microgravity was used to induce weightlessness in mice. Animals were suspended by tail to simulate microgravity for 21 days. Effect of simulated microgravity on the expression G-proteins was studied in various tissues. Specific antibodies were used to probe stimulatory and inhibitory G-proteins on Western Blots. Our results suggested that there is a significant increase in the amounts G-protein subunits in hind limb suspended tissues compared to controls. Further experiments are required to establish any relationship in the apparent changes in G-proteins and inositol phosphates.

  7. Research in human performance related to space: A compilation of three projects/proposals

    Science.gov (United States)

    Hasson, Scott M.

    1989-01-01

    Scientific projects were developed in order to maximize performance in space and assure physiological homeostatis upon return. Three projects that are related to this common goal were either initiated or formulated during the Faculty Fellowship Summer Program. The projects were entitled: (1) Effect of simulated weightlessness (bed rest) on muscle performance and morphology; (2) Effect of submaximal eccentric muscle contractions on muscle injury, soreness and performance: A grant proposal; and (3) Correlation between isolated joint dynamic muscle strength to end-effector strength of the push and pull extravehicular activity (EVA) ratchet maneuver. The purpose is to describe each of these studies in greater detail.

  8. Coherence between brain cortical function and neurocognitive performance during changed gravity conditions.

    Science.gov (United States)

    Brümmer, Vera; Schneider, Stefan; Vogt, Tobias; Strüder, Heiko; Carnahan, Heather; Askew, Christopher D; Csuhaj, Roland

    2011-05-23

    Previous studies of cognitive, mental and/or motor processes during short-, medium- and long-term weightlessness have only been descriptive in nature, and focused on psychological aspects. Until now, objective observation of neurophysiological parameters has not been carried out--undoubtedly because the technical and methodological means have not been available--, investigations into the neurophysiological effects of weightlessness are in their infancy (Schneider et al. 2008). While imaging techniques such as positron emission tomography (PET) and magnetic resonance imaging (MRI) would be hardly applicable in space, the non-invasive near-infrared spectroscopy (NIRS) technique represents a method of mapping hemodynamic processes in the brain in real time that is both relatively inexpensive and that can be employed even under extreme conditions. The combination with electroencephalography (EEG) opens up the possibility of following the electrocortical processes under changing gravity conditions with a finer temporal resolution as well as with deeper localization, for instance with electrotomography (LORETA). Previous studies showed an increase of beta frequency activity under normal gravity conditions and a decrease under weightlessness conditions during a parabolic flight (Schneider et al. 2008a+b). Tilt studies revealed different changes in brain function, which let suggest, that changes in parabolic flight might reflect emotional processes rather than hemodynamic changes. However, it is still unclear whether these are effects of changed gravity or hemodynamic changes within the brain. Combining EEG/LORETA and NIRS should for the first time make it possible to map the effect of weightlessness and reduced gravity on both hemodynamic and electrophysiological processes in the brain. Initially, this is to be done as part of a feasibility study during a parabolic flight. Afterwards, it is also planned to use both techniques during medium- and long-term space flight. It

  9. The foundations of space biology and medicine. Volume 2: Ecological and physiological bases of space biology and medicine. Part 3: Effect on the organism of dynamic flight factors. Chapter 1: Principles of gravitational biology

    Science.gov (United States)

    Smith, A. H.

    1972-01-01

    The physical principles of gravitation are discussed, such as gravitational and intertial forces, weight and mass, weightlessness, size and scale effects, scale limits of gravitational effects, and gravity as a biogenic factor. The behavior of the accelerative force gravitation, is described. This law proposes and quantifies the mutual gravitational attraction existing between all bodies of matter, the force being proportional to the product of masses, and inversely related to the square of the distance separating them. Gravity orientation, chronic acceleration, and hematology are examined. Systematic responses, such as circulation and renal functions, are also considered, along with animal response to a decreased acceleration field and physiology of hyper- and hypodynamic fields.

  10. The NASA Space Biology Program

    Science.gov (United States)

    Halstead, T. W.

    1982-01-01

    A discussion is presented of the research conducted under the auspices of the NASA Space Biology Program. The objectives of this Program include the determination of how gravity affects and how it has shaped life on earth, the use of gravity as a tool to investigate relevant biological questions, and obtaining an understanding of how near-weightlessness affects both plants and animals in order to enhance the capability to use and explore space. Several areas of current developmental research are discussed and the future focus of the Program is considered.

  11. Absence of a growth hormone effect on rat soleus atrophy during a 4-day spaceflight

    Science.gov (United States)

    Jiang, Bian; Roy, Roland R.; Navarro, Christine; Edgerton, V. R.

    1993-01-01

    The effect of a 4-day-long spaceflight on the size and the enzyme properties of soleus fibers of rats and the effects of exogenous growth hormone (GH) on the atrophic response of the soleus muscle were investigated in four groups of rats: (1) control, (2) control plus GH treatment, (3) flight, and (4) flight plus GH treatment. Results showed that the fiber size and the type of myosin heavy chain expressed fibers (but not the metabolic properties) of the soleus were affected by four days of weightlessness and that the effects were not ameliorated by the administration of growth hormone.

  12. The Role of Plants in Space Exploration: Some History and Background

    Science.gov (United States)

    Wheeler, Raymond M.

    2016-01-01

    For over 3 decades, NASA has sponsored research on crops for human life support in space. Specialized watering techniques have even been tested for weightless settings, but most studies used conventional watering, such as hydroponics, which should work well on surface settings of the Moon or Mars. NASAs testing has spanned a wide range of crops and studied innovative techniques to increase yields, reduce power, minimize growing volume, and recycle water and nutrients. These issues closely parallel challenges faced in terrestrial controlled environment agriculture, which is expanding around the world.

  13. Impact accelerations

    Science.gov (United States)

    Vongierke, H. E.; Brinkley, J. W.

    1975-01-01

    The degree to which impact acceleration is an important factor in space flight environments depends primarily upon the technology of capsule landing deceleration and the weight permissible for the associated hardware: parachutes or deceleration rockets, inflatable air bags, or other impact attenuation systems. The problem most specific to space medicine is the potential change of impact tolerance due to reduced bone mass and muscle strength caused by prolonged weightlessness and physical inactivity. Impact hazards, tolerance limits, and human impact tolerance related to space missions are described.

  14. STS-47 MS Jemison trains in SLJ module at MSFC Payload Crew Training Complex

    Science.gov (United States)

    1992-01-01

    STS-47 Endeavour, Orbiter Vehicle (OV) 105, Mission Specialist (MS) Mae C. Jemison, wearing Autogenic Feedback Training System 2 suit, works with the Frog Embryology Experiment in a General Purpose Workstation (GPWS) in the Spacelab Japan (SLJ) module mockup at the Payload Crew Training Complex. The experiment will study the effects of weightlessness on the development of frog eggs fertilized in space. The Payload Crew Training Complex is located at the Marshall Space Flight Center (MSFC) in Huntsville, Alabama. View provided with alternate number 92P-139.

  15. Design of specific hardware to obtain embryos and maintain adult urodele amphibians aboard a space station

    Science.gov (United States)

    Husson, D.; Chaput, D.; Bautz, A.; Davet, J.; Durand, D.; Dournon, C.; Duprat, A. M.; Gualandris-Parisot, L.

    The study of the influence of weightlessness on fertilization and embryonic development of a vertebrate is of importance in the understanding of basic embryogenesis and in the preparation of the future exploration of space. Accordingly, specific hardware was designed to perform experiments on board the MIR space station with an amphibian vertebrate model, taking into account the biological requirements and the multiple constraints of a longterm space mission. This paper describes the biological uses and presents the technological specifications of the device developed under CNES management. The hardware was adapted to and is compatible with biological requirements as confirmed by three experiments performed in space on board the orbital MIR station.

  16. Nonaxisymmetric shapes of a magnetically levitated and spinning water droplet.

    Science.gov (United States)

    Hill, R J A; Eaves, L

    2008-12-05

    The shape of a weightless spinning liquid droplet is governed by the balance between the surface tension and centrifugal forces. The axisymmetric shape for slow rotation becomes unstable to a nonaxisymmetric distortion above a critical angular velocity, beyond which the droplet progresses through a series of 2-lobed shapes. Theory predicts the existence of a family of 3- and 4-lobed equilibrium shapes at higher angular velocity. We investigate the formation of a triangular-shaped magnetically levitated water droplet, driven to rotate by the Lorentz force on an ionic current within the droplet. We also study equatorial traveling waves which give the droplet threefold, fourfold, and fivefold symmetry.

  17. Methods for study of cardiovascular adaptation of small laboratory animals during exposure to altered gravity. [hypothermia for cardiovascular control and cancer therapy

    Science.gov (United States)

    Popovic, V.

    1973-01-01

    Several new techniques are reported for studying cardiovascular circulation in small laboratory animals kept in metabolic chambers. Chronical cannulation, miniaturized membrane type heart-lung machines, a prototype walking chamber, and a fluorocarbon immersion method to simulate weightlessness are outlined. Differential hypothermia work on rat cancers provides localized embedding of radionuclides and other chemotherapeutical agents in tumors and increases at the same time blood circulation through the warmed tumor as compared to the rest of the cold body. Some successful clinical applications of combined chemotherapy and differential hypothermia in skin cancer, mammary tumors, and brain gliomas are described.

  18. STS-31 MS Sullivan exits airlock mockup during JSC WETF underwater simulation

    Science.gov (United States)

    1990-01-01

    STS-31 Mission Specialist (MS) Kathryn D. Sullivan, fully suited in an extravehicular mobility unit (EMU) and holding a semirigid tether (SRT) and ratchet caddy assembly, egresses the airlock (AL) mockup during an underwater simulation in JSC's Weightless Environment Training Facility (WETF) Bldg 29 pool. The open AL extravehicular (EV) hatch appears in the foreground as Sullivan backs out into the payload bay (PLB). Though no extravehicular activity (EVA) is planned for STS-31, two crewmembers train for contingencies that would necessitate leaving the shirt sleeve environment of Discovery's, Orbiter Vehicle (OV) 103's, cabin and performing chores with their Hubble Space Telescope (HST) payload or related hardware in the PLB.

  19. Influences of Vestibular System on Sympathetic Nervous System. Implications for countermeasures.

    Science.gov (United States)

    Denise, Pr Pierre

    As gravity is a direct and permanent stress on body fluids, muscles and bones, it is not surpris-ing that weightlessness has important effects on cardiovascular and musculo-skeletal systems. However, these harmful effects do not totally result from the removal of the direct stress of gravity on these organs, but are also partially and indirectly mediated by the vestibular sys-tem. Besides its well known crucial role in spatial orientation and postural equilibrium, it is now clear that the vestibular system is also involved in the regulation of other important physi-ological systems: respiratory and cardiovascular systems, circadian regulation, food intake and even bone mineralization. The neuroanatomical substrate for these vestibular-mediated reg-ulations is still poorly defined, but there is much evidence that vestibular system has strong impacts not only on brainstem autonomic centers but on many hypothalamic nuclei as well. As autonomic nervous system controls almost all body organs, bringing into play the vestibular system by hypergravity or microgravity could virtually affects all major physiological func-tions. There is experimental evidence that weightlessness as well as vestibular lesion induce sympathetic activation thus participating in space related physiological alterations. The fact that some effects of weightlessness on biological systems are mediated by the vestibular system has an important implication for using artificial gravity as a countermeasure: artificial gravity should load not only bones and the cardiovascular system but the vestibular system as well. In short-arm centrifuges, the g load at the head level is low because the head is near the axis of rotation. If the vestibular system is involved in cardiovascular deconditioning and bone loss during weightlessness, it would be more effective to significantly stimulate it and thus it would be necessary to place the head off-axis. Moreover, as the otolithic organs are non longer stimu-lated in

  20. [Catecholamines and their metabolic enzymes in the rat myocardium after a flight on the Kosmos-936 biosatellite].

    Science.gov (United States)

    Kwetncanski, R; Tigranian, R A; Torda, T

    1982-01-01

    In the myocardium of the weightless and centrifuged rats flown for 18.5 days onboard the biosatellite Cosmos-936 the catecholamine concentration and activity of enzymes involved in their synthesis and degradation--dopamine-beta-hydroxylase, monoamine oxidase and catechol-O-methyl transferase--were measured. The catecholamine concentration in the myocardium of both flight groups significantly increased, and the enzyme activity did not change. These results suggest that an exposure to space flight increases the catecholamine concentration and exerts no effect on their synthesis and degradation in the rat myocardium.

  1. [Skeletal muscle mixed fiber tissue metabolism in rats after a flight on the Kosmos-690 biosatellite].

    Science.gov (United States)

    Gaevskaia, M S; Belitskaia, R A; Kolganova, N S; Kolchina, E V; Kurkina, L M

    1979-01-01

    On the R+O day the quadriceps muscle of rats showed a decrease in the content of T protein and an inhibition of LDH activity of sacroplasmatic proteins. These changes resulted from the combined affect of space flight factors and gamma-irradiation, and may be considered as a decline of compensatory synthetic processes responsible for the recovery of muscle proteins in weightlessness. Inhibition of the age-associated shift of the M:H ratio of LDH found on the R+25 day can be attributed to the inhibitory effect of gamma-irradiation. No change in the content of glycogen in the gastrocnemius muscle of flight rats was noted.

  2. [The indices of water-salt metabolism and of the endocrine status in monkeys after flights on the Kosmos biological satellites].

    Science.gov (United States)

    Korol'kov, V I; Dotsenko, M A; Larina, I M; Shakhmatova, E I; Natochin, Iu V

    1996-01-01

    Findings of studying the indices of water-salt metabolism and endocrine status of monkeys after their exposure in the weightless environment onboard the biological satellites of Earth have revealed a change in the blood serum concentrations of electrolytes which is indicative of instability of the system responsible for maintenance of the fluid-mineral homeostasis during readaptation. Results of studying the endocrine status of monkeys infer alteration in calcium metabolism, i.e. decreased levels of parathyroid hormone, calcitonin and the transport form of vitamin D3.

  3. [Catecholamines and their metabolic enzymes in the hypothalamus of rats after a flight on the Kosmos-782 biosatellite].

    Science.gov (United States)

    Kvetnanský, R; Tigranian, R A; Torda, T; Babusiková, D; Jahnová, E

    1979-01-01

    The concentration of catecholamines, and activity of enzymes involved in their synthesis (tyrosine hydroxylase and dopamine-beta-hydroxylase) and degradation (monoamine oxidase) were measured in the hypothalamus of rats flown for 19.5 days aboard the biosatellite Cosmos-782, synchronous and vivarium controls sacrificed on R+O and R+25 days. No significant changes in the above parameters of the flight rats were found. The findings give evidence that a prolonged space flight induces no changes in the content, synthesis or degradation of catecholamines in the rat hypothalamus. This seems to indicate that weightlessness does not act as an acute stressor.

  4. [Lactate dehydrogenase isoenzymatic makeup of the skeletal muscles of rats after a flight on the Kosmos-690 biosatellite].

    Science.gov (United States)

    Petrova, N V

    1978-01-01

    The isoenzyme composition of lactate dehydrogenase in the soleus and plantaris muscles of rats which had flown for 20.5 days onboard the biosatellite Cosmos-690 equipped with a radiation source was studied. Difference in the isoenzyme composition of lactate dehydrogenase in flight and synchronous rats disappeared 27 days after the experiments; however, some changes persisted as compared with vivarium controls. The data obtained give evidence that irradiation-induced effects in skeletal muscles manifested themselves at a far later stage than weightlessness-induced changes.

  5. [Morphofunctional properties of the peripheral blood and bone marrow cells of rats following a flight on board the Kosmos-936 biosatellite].

    Science.gov (United States)

    Kozinets, G I; Korol'kov, V I; Britvan, I I; Bykova, I A; Spitsyna, N E

    1983-01-01

    Morphofunctional properties of peripheral blood cells of Cosmos-936 rats were examined, using morphological, interferometric and electron microscopic techniques. As follows from the morphological data, immediately after recovery the weightless rats showed symptoms of a stress reaction which disappeared by R+3. The centrifuged rats exhibited less expressed symptoms of this sort. The percentage of bone marrow cell distribution was shifted towards enhanced myelopoiesis and diminished erythropoiesis. By the end of the readaptation period the ratio of bone marrow cell composition returned to normal. Interferometric and electron microscopic examinations did not reveal any irreversible changes in the structure and function of cells that may be caused by zero-g.

  6. Effect of bedrest on thermoregulation.

    Science.gov (United States)

    Williams, B. A.; Reese, R. D.

    1972-01-01

    Attempt to determine what changes occur in the thermoregulatory control system during the simulated weightlessness of prolonged bed rest, as determined by measurement of the onset of sweating in response to an imposed heat load. The threshold for sweating occurred at a lower mean skin temperature and the normal vasodilation response appears to be impaired slightly. It is possible that the result of bed rest is to decrease the circulatory capability of the body (autonomic dysfunction) and the effect on the thermoregulatory system, therefore, is to decrease vasomotor heat loss capability.

  7. Exercise thermoregulation - Possible effects of spaceflight

    Science.gov (United States)

    Fortney, Suzanne M.

    1991-01-01

    Changes in thermoregulation during spaceflight could result in an inability to tolerate ambient conditions or exercise tasks that were readily tolerated preflight. Weightlessness may alter heat production by changing metabolic rate, circadian rhythms of heat production, or work efficiency. It may impair heat loss by reducing convective and evaporative heat exchange. In addition, crewmembers may become less fit, less heat acclimated, hypohydrated, or have altered thermal sensitivity. Three scenarios are described: exercise conditioning in the mid deck, EVA, and emergency egress. Each scenario is discussed in terms of potential thermal challenges and possible consequences on crew performance.

  8. Ribbon Synaptic Plasticity in Gravity Sensors of Rats Flown on Neurolab

    Science.gov (United States)

    Ross, Muriel D.; Varelas, Joseph

    2003-01-01

    Previous spaceflight experiments (Space Life Sciences-1 and -2 (SLS-1 and SLS-2)) first demonstrated the extraordinary ability of gravity sensor hair cells to change the number, kind, and distribution of connections (synapses) they make to other cells while in weightlessness. The number of synapses in hair cells in one part of the inner ear (the utricle) was markedly elevated on flight day 13 (FD13) of SLS-2. Unanswered questions, however, were whether these increases in synapses occur rapidly and whether they remain stable in weightlessness. The answers have implications for long-duration human space travel. If gravity sensors can adapt quickly, crews may be able to move easily between different gravity levels, since the sensors will adapt rapidly to weightlessness on the spacecraft and then back to Earth's gravity when the mission ends. This ability to adapt is also important for recovery from balance disorders. To further our understanding of this adaptive potential (a property called neuronal synaptic plasticity), the present Neurolab research was undertaken. Our experiment examined whether: (a) increases in synapses would remain stable throughout the flight, (b) changes in the number of synapses were uniform across different portions of the gravity sensors (the utricle and saccule), and (c) synaptic changes were similar for the different types of hair cells (Type I and Type II). Utricular and saccular maculae (the gravity-sensing portions of the inner ear) were collected in flight from rats on FD2 and FD14. Samples were also collected from control rats on the ground. Tissues were prepared for ultrastructural study. Hair cells and their ribbon synapses were examined in a transmission electron microscope. Synapses were counted in all hair cells in 50 consecutive sections that crossed the striolar zone. Results indicate that utricular hair cell synapses initially increased significantly in number in both types of hair cells by FD2. Counts declined by FD14, but

  9. Diagram of Calcium Movement in the Human Body

    Science.gov (United States)

    2002-01-01

    This diagram shows the normal pathways of calcium movement in the body and indicates changes (green arrows) seen during preliminary space flight experiments. Calcium plays a central role because 1) it gives strength and structure to bone and 2) all types of cells require it to function normally. To better understand how and why weightlessness induces bone loss, astronauts have participated in a study of calcium kinetics -- that is, the movement of calcium through the body, including absorption from food, and its role in the formation and breakdown of bone.

  10. Characteristic of changes in the structure and metabolism of the vastus lateralis muscles in monkeys after space flight.

    Science.gov (United States)

    Belozerova, I N; Nemirovskaya, T L; Shenkman, B S; Kozlovskaya, I B

    2003-09-01

    Monkeys subjected to space flight were found to have significant decreases in the sizes of slow and rapid fibers in the vastus lateralis muscle, due not only to weightlessness but also, to some extent, to restriction of movement activity within the capsule. The quantity of total protein in muscle fibers did not decrease. The respiratory peak in the pool of vastus lateralis muscle fibers decreased after space flight, as did the activity of oxidative enzymes (particularly in rapid fibers of the vastus lateralis muscle).

  11. Mathematical modeling of acute and chronic cardiovascular changes during Extended Duration Orbiter (EDO) flights

    Science.gov (United States)

    White, Ronald J.; Leonard, Joel I.; Srinivasan, R. Srini; Charles, John B.

    1991-01-01

    The purpose of NASA's Extended Duration Orbiter program is a gradual extension of the capabilities of the Space Shuttle Orbiter beyond its current 7-10 day limit on mission duration, as warranted by deepening understanding of the long-term physiological effects of weightlessness. Attention is being given to the cardiovascular problem of orthostatic tolerance loss due to its adverse effects on crew performance and health during reentry and initial readaptation to earth gravity. An account is given of the results of the application of proven mathematical models of circulatory and cardiovascular systems under microgravity conditions.

  12. Artificial gravity - The evolution of variable gravity research

    Science.gov (United States)

    Fuller, Charles A.; Sulzman, Frank M.; Keefe, J. Richard

    1987-01-01

    The development of a space life science research program based on the use of rotational facilities is described. In-flight and ground centrifuges can be used as artificial gravity environments to study the following: nongravitational biological factors; the effects of 0, 1, and hyper G on man; counter measures for deconditioning astronauts in weightlessness; and the development of suitable artificial gravity for long-term residence in space. The use of inertial fields as a substitute for gravity, and the relations between the radius of the centrifuge and rotation rate and specimen height and rotation radius are examined. An example of a centrifuge study involving squirrel monkeys is presented.

  13. Microbial growth and physiology in space - A review

    Science.gov (United States)

    Cioletti, Louis A.; Mishra, S. K.; Pierson, Duane L.

    1991-01-01

    An overview of microbial behavior in closed environments is given with attention to data related to simulated microgravity and actual space flight. Microbes are described in terms of antibiotic sensitivity, subcellular structure, and physiology, and the combined effects are considered of weightlessness and cosmic radiation on human immunity to such microorganisms. Space flight results report such effects as increased phage induction, accelerated microbial growth rates, and the increased risk of disease communication and microbial exchange aboard confining spacecraft. Ultrastructural changes are also noted in the nuclei, cell membranes, and cytoplasmic streaming, and it appears that antibiotic sensitivity is reduced under both actual and simulated conditions of spaceflight.

  14. SPACE LIFE SCIENCE IN 2000-2001

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Chinese scientists studied some of the problems in the field of space life science and achieved success in the area during 2000-2001. Space biological experi ments were carried out in the orbit and the results of ground studies on protein crystallization, space radiation, space motion sickness were introduced in this paper. The influences of simulated weightlessness on the brain-function, the car diovascular, endocrine hormones, immunity, skeletal and muscle systems were presented. In addition, gravity medicine and space environment medicine, as well as countermeasures to space deconditioning, such as the traditional Chinese medicine, were also reported.

  15. ATLS-stowage and deployment testing of medical supplies and pharmaceuticals

    Science.gov (United States)

    Gosbee, John; Benz, Darren; Lloyd, Charles W.; Bueker, Richard; Orsak, Debra

    1991-01-01

    The objective is to evaluate stowage and deployment methods for the Health Maintenance Facility (HMF) during microgravity. The specific objectives of this experiment are: (1) to evaluate the stowage and deployment mechanisms for the medical supplies; and (2) to evaluate the procedures for performing medical scenarios. To accomplish these objectives, the HMF test mini-racks will contain medical equipment mounted in the racks; and self-contained drawers with various mechanisms for stowing and deploying items. The medical supplies and pharmaceuticals will be destowed, handled, and restowed. The in-flight test procedures and other aspects of the KC-135 parabolic flight test to simulate weightlessness are presented.

  16. The role of depressed metabolism in increased radio-resistance

    Science.gov (United States)

    Musacchia, X. J.

    1975-01-01

    The results of experiments on hamsters and rats to determine physiological responses to various temperature conditions are presented. The experimental methods described are considered to be applicable to future mammalian experiments in space. Renal function was examined in the golden hamster as a function of body temperature. Hamsters were also acclimated to heat and metabolic rates, body temperature, skin temperature, cardiac distribution and whole body hematocrits were measured. In addition, the effects of heat stress on the intestinal transport of sugars in the hamster and rat were studied. The biological effects of prolonged space flight and methods of simulating weightlessness are also discussed.

  17. Gravitropic responses of the Avena coleoptile in space and on clinostats. I. Gravitropic response thresholds

    Science.gov (United States)

    Brown, A. H.; Chapman, D. K.; Johnsson, A.; Heathcote, D.

    1995-01-01

    We conducted a series of gravitropic experiments on Avena coleoptiles in the weightlessness environment of Spacelab. The purpose was to test the threshold stimulus, reciprocity rule and autotropic reactions to a range of g-force stimulations of different intensities and durations The tests avoided the potentially complicating effects of earth's gravity and the interference from clinostat ambiguities. Using slow-speed centrifuges, coleoptiles received transversal accelerations in the hypogravity range between 0.l and 1.0 g over periods that ranged from 2 to 130 min. All responses that occurred in weightlessness were compared to clinostat experiments on earth using the same apparatus. Characteristic gravitropistic response patterns of Atuena were not substantially different from those observed in ground-based experiments. Gravitropic presentation times were extrapolated. The threshold at 1.0 g was less than 1 min (shortest stimulation time 2 min), in agreement with values obtained on the ground. The least stimulus tested, 0.1 g for 130 min, produced a significant response. Therefore the absolute threshold for a gravitropic response is less than 0.1 g.

  18. Does Simulated Spaceflight Modify Epigenetic Status During Bone Remodeling?

    Science.gov (United States)

    Thomas, Nicholas J.; Stevick, Rebecca J.; Tran, Luan H.; Nalavadi, Mohit O.; Almeida, Eduardo A.C.; Globus, Ruth K.; Alwood, Joshua S.

    2015-01-01

    Little is known about the effects of spaceflight conditions on epigenetics. The term epigenetics describes changes to the genome that can affect expression of a gene without changes to the sequence of DNA. Epigenetic processes are thought to underlie cellular differentiation, where transcription of specific genes occurs in response to key stimuli, and may be heritable - passing from one cell to its daughter cell. We hypothesize that the mechanical environment during spaceflight, namely microgravity-induced weightlessness or exercise regulate gene expression in the osteoblast-lineage cells both to control bone formation by osteoblasts and bone resorption by osteoclasts, which continually shapes bone structure throughout life. Similarly we intend to evaluate how radiation regulates these same bone cell activity and differentiation related genes. We further hypothesize that the regulation in bone cell gene expression is at least partially controlled through epigenetic mechanisms of methylation or small non-coding RNA (microRNAs). We have acquired preliminary data suggesting that global genome methylation is modified in response to axial compression of the tibia - a model of exercise. We intend to pursue these hypotheses wherein we will evaluate changes in gene expression and, congruently, changes in epigenetic state in bones from mice subjected to the aforementioned conditions: hindlimb unloading to simulate weightlessness, axial compression of the tibia, or radiation exposure in order to gain insight into the role of epigenetics in spaceflight-induced bone loss.

  19. Searching for the Origin through Central Nervous System: A Review and Thought which Related to Microgravity, Evolution, Big Bang Theory and Universes, Soul and Brainwaves, Greater Limbic System and Seat of the Soul.

    Science.gov (United States)

    Idris, Zamzuri

    2014-07-01

    Cerebrospinal fluid (CSF) serves buoyancy. The buoyancy thought to play crucial role in many aspects of the central nervous system (CNS). Weightlessness is produced mainly by the CSF. This manuscript is purposely made to discuss its significance which thought contributing towards an ideal environment for the CNS to develop and function normally. The idea of microgravity environment for the CNS is supported not only by the weightlessness concept of the brain, but also the noted anatomical position of the CNS. The CNS is positioned in bowing position (at main cephalic flexure) which is nearly similar to an astronaut in a microgravity chamber, fetus in the amniotic fluid at early gestation, and animals and plants in the ocean or on the land. Therefore, this microgravity position can bring us closer to the concept of origin. The hypothesis on 'the origin' based on the microgravity were explored and their similarities were identified including the brainwaves and soul. Subsequently a review on soul was made. Interestingly, an idea from Leonardo da Vinci seems in agreement with the notion of seat of the soul at the greater limbic system which has a distinctive feature of "from God back to God".

  20. The effect of blood volume loss on cardiovascular response to lower body negative pressure using a mathematical model

    Science.gov (United States)

    Karam, E. H.; Srinivasan, R. S.; Charles, J. B.; Fortney, S. M.

    1994-01-01

    Different mathematical models of varying complexity have been proposed in recent years to study the cardiovascular (CV) system. However, only a few of them specifically address the response to lower body negative pressure (LBNP), a stress that can be applied in weightlessness to predict changes in orthostatic tolerance. Also, the simulated results produced by these models agree only partially with experimental observations. In contrast, the model proposed by Melchior et al., and modified by Karam et al. is a simple representation of the CV system capable of accurately reproducing observed LBNP responses up to presyncopal levels. There are significant changes in LBNP response due to a loss of blood volume and other alterations that occur in weightlessness and related one-g conditions such as bedrest. A few days of bedrest can cause up to 15% blood volume loss (BVL), with consequent decreases in both stroke volume and cardiac output, and increases in heart rate, mean arterial pressure, and total peripheral resistance. These changes are more pronounced at higher levels of LBNP. This paper presents the results of a simulation study using our CV model to examine the effect of BVL on LBNP response.

  1. Spacelab 1 hematology experiment (INS103): Influence of space flight on erythrokinetics in man

    Science.gov (United States)

    Leach, C. S.; Chen, J. P.; Crosby, W.; Dunn, C. D. R.; Johnson, P. C.; Lange, R. D.; Larkin, E.; Tavassoli, M.

    1985-01-01

    An experiment conducted on the 10-day Spacelab 1 mission aboard the ninth Space Shuttle flight in November to December 1983 was designed to measure factors involved in the control of erythrocyte turnover that might be altered during weightlessness. Blood samples were collected before, during, and after the flight. Immediately after landing, red cell mass showed a mean decrease of 9.3 percent in the four astronauts. Neither hyperoxia nor an increase in blood phosphate was a cause of the decrease. Red cell survival time and iron incorporation postflight were not significantly different from their preflight levels. Serum haptoglobin did not decrease, indicating that intravascular hemolysis was not a major cause of red cell mass change. An increase in serum ferritin after the second day of flight may have been caused by red cell breakdown early in flight. Erythropoietin levels decreased during and after flight, but preflight levels were high and the decrease was not significant. The space flight-induced decrease in red cell mass may result from a failure of erythropoiesis to replace cells destroyed by the spleen soon after weightlessness is attained.

  2. Rate control system algorithm developed in state space for models with parameter uncertainties

    Directory of Open Access Journals (Sweden)

    Adilson Jesus Teixeira

    2011-09-01

    Full Text Available Researching in weightlessness above the atmosphere needs a payload to carry the experiments. To achieve the weightlessness, the payload uses a rate control system (RCS in order to reduce the centripetal acceleration within the payload. The rate control system normally has actuators that supply a constant force when they are turned on. The development of an algorithm control for this rate control system will be based on the minimum-time problem method in the state space to overcome the payload and actuators dynamics uncertainties of the parameters. This control algorithm uses the initial conditions of optimal trajectories to create intermediate points or to adjust existing points of a switching function. It associated with inequality constraint will form a decision function to turn on or off the actuators. This decision function, for linear time-invariant systems in state space, needs only to test the payload state variables instead of spent effort in solving differential equations and it will be tuned in real time to the payload dynamic. It will be shown, through simulations, the results obtained for some cases of parameters uncertainties that the rate control system algorithm reduced the payload centripetal acceleration below μg level and keep this way with no limit cycle.

  3. Protein pattern of Xenopus laevis embryos grown in simulated microgravity.

    Science.gov (United States)

    Tedeschi, Gabriella; Pagliato, Lara; Negroni, Manuela; Montorfano, Gigliola; Corsetto, Paola; Nonnis, Simona; Negri, Armando; Rizzo, Angela Maria

    2011-03-01

    Numerous studies indicate that microgravity affects cell growth and differentiation in many living organisms, and various processes are modified when cells are placed under conditions of weightlessness. However, until now, there is no coherent explanation for these observations, and little information is available concerning the biomolecules involved. Our aim has been to investigate the protein pattern of Xenopus laevis embryos exposed to simulated microgravity during the first 6 days of development. A proteomic approach was applied to compare the protein profiles of Xenopus embryos developed in simulated microgravity and in normal conditions. Attention was focused on embryos that do not present visible malformations in order to investigate if weightlessness has effects at protein level in the absence of macroscopic alterations. The data presented strongly suggest that some of the major components of the cytoskeleton vary in such conditions. Three major findings are described for the first time: (i) the expression of important factors involved in the organization and stabilization of the cytoskeleton, such as Arp (actin-related protein) 3 and stathmin, is heavily affected by microgravity; (ii) the amount of the two major cytoskeletal proteins, actin and tubulin, do not change in such conditions; however, (iii) an increase in the tyrosine nitration of these two proteins can be detected. The data suggest that, in the absence of morphological alterations, simulated microgravity affects the intracellular movement system of cells by altering cytoskeletal proteins heavily involved in the regulation of cytoskeleton remodelling.

  4. A suspension model for hypokinetic/hypodynamic and antiorthostatic responses in the mouse

    Science.gov (United States)

    Steffen, J. M.; Dombrowski, M. J.; Musacchia, X. J.; Sonnenfeld, G.; Mandel, A. D.; Robb, R.

    1984-01-01

    Hypokinetic/hypodynamic and antiorthostatic responses to weightlessness and bedrest were simulated in mice using a suspension technique. Animals were suspended for 1 or 2 weeks in an antiorthostatic posture and positioned to permit freedom of movement but eliminate load bearing by the hindlimbs. Suspended mice exhibited reduced food and water intakes and a rapid 10 percent decrease in body weight to a level which was maintained for the remainder of the suspension period. Diuresis was evident in suspended mice, but the natriuresis and kaliuresis previously observed in the suspended rat were not evident. Differential hindlimb muscle atrophy and increased excretion of urea and ammonia were also noted in suspended mice. Postsuspension recovery studies indicated that the recovery process was highly effective. These results document specific responses in the mouse and similarities in the responses of mice and rats to suspension. These studies expand the utility of the suspension model and suggest that the mouse may be useful in future studies simulating both weightlessness and bedrest.

  5. The Effects of Space Flight on Some Liver Enzymes Concerned with Carbohydrate and Lipid Metabolism in Rats

    Science.gov (United States)

    Abraham, S.; Lin, C. Y.; Klein, H. P.; Volkmann, C.

    1978-01-01

    The activities of about 30 enzymes concerned with carbohydrate and lipid metabolism and the levels of glycogen and of individual fatty acids were measured in livers of rats ex- posed to prolonged space flight (18.5 days) aboard COSMOS 986 Biosatellite. When flight stationary, (FS) and flight centrifuged (FC) rats were compared at recovery (R(sub 0)), decrceases in the activities of glycogen phosphorylase, alpha glycerphosphate, acyl transferase, diglyceride acyl transferase, acconitase and Epsilon-phosphogluconate dehydrogenase were noted in the weightless group (FS). The significance of these findings was strengthened since all activities, showing alterations at R(sub 0), returned to normal 25 days post-flight. Differences were also seen in levels of two liver constituents. When glycogen and total fatty acids of the two groups of flight animals were determined, differences that could be attributed to reduced gravity were observed, the FS group at R(sub 0) contained, on the average, more than twice the amount of glycogen than did controls ad a remarkable shift in the ratio of palmitate to palmitoleate were noted. These metabolic alterations appear to be unique to the weightless condition. Our data justify the conclusion that centrifugation during space flight is equivalent to terrestrial gravity.

  6. The effect of blood volume loss on cardiovascular response to lower body negative pressure using a mathematical model

    Science.gov (United States)

    Karam, E. H.; Srinivasan, R. S.; Charles, J. B.; Fortney, S. M.

    1994-01-01

    Different mathematical models of varying complexity have been proposed in recent years to study the cardiovascular (CV) system. However, only a few of them specifically address the response to lower body negative pressure (LBNP), a stress that can be applied in weightlessness to predict changes in orthostatic tolerance. Also, the simulated results produced by these models agree only partially with experimental observations. In contrast, the model proposed by Melchior et al., and modified by Karam et al. is a simple representation of the CV system capable of accurately reproducing observed LBNP responses up to presyncopal levels. There are significant changes in LBNP response due to a loss of blood volume and other alterations that occur in weightlessness and related one-g conditions such as bedrest. A few days of bedrest can cause up to 15% blood volume loss (BVL), with consequent decreases in both stroke volume and cardiac output, and increases in heart rate, mean arterial pressure, and total peripheral resistance. These changes are more pronounced at higher levels of LBNP. This paper presents the results of a simulation study using our CV model to examine the effect of BVL on LBNP response.

  7. On the biological role of gravity.

    Science.gov (United States)

    Gazenko, O G; Gurjian, A A

    1965-01-01

    The paper is dedicated to the memory of Galileo Galilei whose work is a great contribution to the development of a new branch of science--gravitation biology. Penetration of man into outer space necessitates a study of the role of gravity in the onto- and phylogenetic development of living organisms. This allows one to get insight into the biological action of weightlessness under the conditions of long-term space flight. The paper summarizes some results of the investigation of weightlessness effects in experiments on animals and during flights of Soviet and American astronauts. The rearing of animals in a special centrifuge under the conditions of prolonged action of accelerations simulating an increased gravity affects noticeably the formation of vegetative (height, weight, metabolism) and animal (vestibulo-tonic reflexes) functions as well as reactivity of the organism. Experiments employing the rearing of animals in a centrifuge represent one of the most promising methods of studying the urgent problem--biological action of increased and decreased gravitation conditions.

  8. Mechanistic studies on reduced exercise performance and cardiac deconditioning with simulated zero gravity

    Science.gov (United States)

    Tipton, Charles M.

    1991-01-01

    The primary purpose of this research is to study the physiological mechanisms associated with the exercise performance of rats subjected to conditions of simulated weightlessness. A secondary purpose is to study related physiological changes associated with other systems. To facilitate these goals, a rodent suspension model was developed (Overton-Tipton) and a VO2 max testing procedure was perfected. Three methodological developments occurred during this past year deserving of mention. The first was the refinement of the tail suspension model so that (1) the heat dissipation functions of the caudal artery can be better utilized, and (2) the blood flow distribution to the tail would have less external constriction. The second was the development on a one-leg weight bearing model for use in simulated weightlessness studies concerned with change in muscle mass, muscle enzyme activity, and hind limb blood flow. The chemical body composition of 30 rats was determined and used to develop a prediction equation for percent fat using underwater weighing procedures to measure carcass specific gravity and to calculate body density, body fat, and fat free mass.

  9. An overview of Space Shuttle anthropometry and biomechanics research with emphasis on STS/Mir recumbent seat system design

    Science.gov (United States)

    Klute, Glenn K.; Stoycos, Lara E.

    1994-01-01

    The Anthropometry and Biomechanics Laboratory (ABL) at JSC conducts multi-disciplinary research focusing on maximizing astronaut intravehicular (IVA) and extravehicular (EVA) capabilities to provide the most effective work conditions for manned space flight and exploration missions. Biomechanics involves the measurement and modeling of the strength characteristics of the human body. Current research for the Space Shuttle Program includes the measurement of torque wrench capability during weightlessness, optimization of foot restraint, and hand hold placement, measurements of the strength and dexterity of the pressure gloved hand to improve glove design, quantification of the ability to move and manipulate heavy masses (6672 N or 1500 lb) in weightlessness, and verification of the capability of EVA crewmembers to perform Hubble Space Telescope repair tasks. Anthropometry is the measurement and modeling of the dimensions of the human body. Current research for the Space Shuttle Program includes the measurement of 14 anthropometric parameters of every astronaut candidate, identification of EVA finger entrapment hazards by measuring the dimensions of the gloved hand, definition of flight deck reach envelopes during launch and landing accelerations, and measurement of anthropometric design parameters for the recumbent seat system required for the Shuttle/Mir mission (STS-71, Spacelab M) scheduled for Jun. 1995.

  10. Teaching weight to explicitly address language ambiguities and conceptual difficulties

    Science.gov (United States)

    Taibu, Rex; Schuster, David; Rudge, David

    2017-06-01

    Language ambiguities in concept meanings can exacerbate student learning difficulties and conceptual understanding of physics concepts. This is especially true for the concept of "weight," which has multiple meanings in both scientific and everyday usage. The term weight has been defined in several different ways, with nuances, but in textbooks and teaching the term is almost always defined in one of two ways: operationally either as the contact force between an object and a measuring scale or as the gravitational force on an object due to some other body such as Earth. The use of the same name for different concepts leads to much confusion, especially in accelerating situations, and to conflicting notions of "weightlessness" in free fall situations. In the present paper, we share an innovative approach that initially avoids the term weight entirely while teaching the physics of each situation, and then teaches the language ambiguities explicitly. We developed an instructional module with this approach and implemented it over two terms in three sections of an introductory physics course for preservice elementary teachers. Learning gains for content understanding were assessed using pretests and post-tests. Participants achieved remarkably high gains for both static and accelerating situations. Surveys pre- and postinstruction showed substantially improved appreciation of language issues and ambiguities associated with weight, weightlessness, and free fall. Interviews with instructors teaching the module provided additional insight into the advantages and teaching demands of the new approach.

  11. Simulated microgravity affects some biological characteristics of Lactobacillus acidophilus.

    Science.gov (United States)

    Shao, Dongyan; Yao, Linbo; Riaz, Muhammad Shahid; Zhu, Jing; Shi, Junling; Jin, Mingliang; Huang, Qingsheng; Yang, Hui

    2017-04-01

    The effects of weightlessness on enteric microorganisms have been extensively studied, but have mainly been focused on pathogens. As a major component of the microbiome of the human intestinal tract, probiotics are important to keep the host healthy. Accordingly, understanding their changes under weightlessness conditions has substantial value. This study was carried out to investigate the characteristics of Lactobacillus acidophilus, a typical probiotic for humans, under simulated microgravity (SMG) conditions. The results revealed that SMG had no significant impact on the morphology of L. acidophilus, but markedly shortened its lag phase, enhanced its growth rate, acid tolerance ability up to pH acidophilus to cefalexin, sulfur gentamicin, and sodium penicillin. No obvious effect of SMG was observed on the adhesion ability of L. acidophilus to Caco-2 cells. Moreover, after SMG treatment, both the culture of L. acidophilus and its liquid phase exhibited higher antibacterial activity against S. typhimurium and S. aureus in a time-dependent manner. The SMG treatment also increased the in vitro cholesterol-lowering ability of L. acidophilus by regulating the expression of the key cholesterol metabolism genes CYP7A1, ABCB11, LDLR, and HMGCR in the HepG2 cell line. Thus, the SMG treatment did have considerable influence on some biological activities and characteristics of L. acidophilus related to human health. These findings provided valuable information for understanding the influence of probiotics on human health under simulated microgravity conditions, at least.

  12. The temporal response of bone to unloading

    Science.gov (United States)

    Globus, R. K.; Bikle, D. D.; Morey-Holton, E.

    1984-01-01

    Rats were suspended by their tails with the forelimbs bearing the weight load to simulate the weightlessness of space flight. Growth in bone mass ceased by 1 week in the hindlimbs and lumbar vertebrae in growing rats, while growth in the forelimbs and cervical vertebrae remained unaffected. The effects of selective skeletal unloading on bone formation during 2 weeks of suspension was investigated using radio iostope incorporation (with Ca-45 and H-3 proline) and histomorphometry (with tetracycline labeling). The results of these studies were confirmed by histomorphometric measurements of bone formation using triple tetracycline labeling. This model of simulated weightlessness results in an initial inhibition of bone formation in the unloaded bones. This temporary cessation of bone formation is followed in the accretion of bone mass, which then resumes at a normal rate by 14 days, despite continued skeletal unloading. This cycle of inhibition and resumption of bone formation has profound implication for understanding bone dynamics durng space flight, immobilization, or bed rest and offers an opportunity to study the hormonal and mechanical factors that regulate bone formation.

  13. Cardiovascular autonomic adaptation in lunar and martian gravity during parabolic flight.

    Science.gov (United States)

    Widjaja, Devy; Vandeput, Steven; Van Huffel, Sabine; Aubert, André E

    2015-06-01

    Weightlessness has a well-known effect on the autonomic control of the cardiovascular system. With future missions to Mars in mind, it is important to know what the effect of partial gravity is on the human body. We aim to study the autonomic response of the cardiovascular system to partial gravity levels, as present on the Moon and on Mars, during parabolic flight. ECG and blood pressure were continuously recorded during parabolic flight. A temporal analysis of blood pressure and heart rate to changing gravity was conducted to study the dynamic response. In addition, cardiovascular autonomic control was quantified by means of heart rate (HR) and blood pressure (BP) variability measures. Zero and lunar gravity presented a biphasic cardiovascular response, while a triphasic response was noted during martian gravity. Heart rate and blood pressure are positively correlated with gravity, while the general variability of HR and BP, as well as vagal indices showed negative correlations with increasing gravity. However, the increase in vagal modulation during weightlessness is not in proportion when compared to the increase during partial gravity. Correlations were found between the gravity level and modulations in the autonomic nervous system during parabolic flight. Nevertheless, with future Mars missions in mind, more studies are needed to use these findings to develop appropriate countermeasures.

  14. Circumnutations of sunflower hypocotyls in satellite orbit

    Science.gov (United States)

    Brown, A. H.; Chapman, D. K.; Lewis, R. F.; Venditti, A. L.

    1990-01-01

    The principal objective of the research reported here was to determine whether a plant's periodic growth oscillations, called circumnutations, would persist in the absence of a significant gravitational or inertial force. The definitive experiment was made possible by access to the condition of protracted near weightlessness in an earth satellite. The experiment, performed during the first flight of Spacelab on the National Aeronautics and Space Administration shuttle, Columbia, in November and December, 1983, tested a biophysical model, proposed in 1967, that might account for circumnutation as a gravity-dependent growth response. However, circumnutations were observed in microgravity. They continued for many hours without stimulation by a significant g-force. Therefore, neither a gravitational nor an inertial g-force was an absolute requirement for initiation [correction of initation] or continuation of circumnutation. On average, circumnutation was significantly more vigorous in satellite orbit than on earth-based clinostats. Therefore, at least for sunflower (Helianthus annuus L.) circumnutation, clinostatting is not the functional equivalent of weightlessness.

  15. The effect of space microgravity on the physiological activity of mammalian resident cardiac stem cells

    Science.gov (United States)

    Belostotskaya, Galina; Zakharov, Eugeny

    Prolonged exposure to weightlessness during space flights is known to cause depression of heart function in mammals. The decrease in heart weight and its remodeling under the influence of prolonged weightlessness (or space microgravity) is assumed to be due to both morphological changes of working cardiomyocytes and their progressive loss, as well as to possible depletion of resident cardiac stem cells (CSCs) population, or their inability to self-renewal and regeneration of muscle tissue under conditions of weightlessness. We have previously shown that the presence of different maturity clones formed by resident CSCs not only in culture but also in the mammalian myocardium can be used as an indicator of the regenerative activity of myocardial cells [Belostotskaya, et al., 2013: 2014]. In this study, we were interested to investigate whether the 30-day near-Earth space flight on the spacecraft BION-M1 affects the regenerative potential of resident CSCs. Immediately after landing of the spacecraft, we had examined the presence of resident c-kit+, Sca-1+ and Isl1+ CSCs and their development in suspension of freshly isolated myocardial cells of C57BL mice in comparison to controls. Cardiac cell suspension was obtained by enzymatic digestion of the heart [Belostotskaya and Golovanova, 2014]. Immunocytochemically stained preparations of fixed cells were analyzed with confocal microscope Leica TCS SP5 (Germany) in the Resource Center of St-Petersburg State University. CSCs were labeled with appropriate antibodies. CSCs differentiation into mature cardiomyocytes was verified using antibodies to Sarcomeric α-Actinin and Cardiac Troponin T. Antibodies to Connexin43 were used to detect cell-cell contacts. All antibodies were conjugated with Alexa fluorochromes (488, 532, 546, 568, 594 and/or 647 nm), according to Zenon-technology (Invitrogen). It has been shown that, under identical conditions of cell isolation, more complete digestion of heart muscle was observed in

  16. The new Drop Tower catapult system

    Science.gov (United States)

    von Kampen, Peter; Kaczmarczik, Ulrich; Rath, Hans J.

    2006-07-01

    The Center of Applied Space Technology and Microgravity (ZARM) was founded in 1985 as an institute of the University Bremen, which focuses on research on gravitational and space-related phenomena. In 1988, the construction of the "Drop Tower" began. Since then, the eye-catching tower with a height of 146 m and its characteristic glass roof has become the emblem of the technology centre in Bremen. The Drop Tower Bremen provides a facility for experiments under conditions of weightlessness. Items are considered weightless, when they are in "free fall", i.e. moving without propulsion within the gravity field of the earth. The height of the tower limits the simple "free fall" experiment period to max. 4.74 s. With the inauguration of the catapult system in December 2004, the ZARM is entering a new dimension. This world novelty will meet scientists' demands of extending the experiment period up to 9.5 s. Since turning the first sod on May 3rd, 1988, the later installation of the catapult system has been taken into account by building the necessary chamber under the tower. The catapult system is located in a chamber 10 m below the base of the tower. This chamber is almost completely occupied by 12 huge pressure tanks. These tanks are placed around the elongation of the vacuum chamber of the drop tube. In its centre there is the pneumatic piston that accelerates the drop capsule by the pressure difference between the vacuum inside the drop tube and the pressure inside the tanks. The acceleration level is adjusted by means of a servo hydraulic breaking system controlling the piston velocity. After only a quarter of a second the drop capsule achieves its lift-off speed of 175 km/h. With this exact speed, the capsule will rise up to the top of the tower and afterwards fall down again into the deceleration unit which has been moved under the drop tube in the meantime. The scientific advantages of the doubled experiment time are obvious: during almost 10 s of high

  17. The exercise and environmental physiology of extravehicular activity

    Science.gov (United States)

    Cowell, Stephenie A.; Stocks, Jodie M.; Evans, David G.; Simonson, Shawn R.; Greenleaf, John E.

    2002-01-01

    Extravehicular activity (EVA), i.e., exercise performed under unique environmental conditions, is indispensable for supporting daily living in weightlessness and for further space exploration. From 1965-1996 an average of 20 h x yr(-1) were spent performing EVA. International Space Station (ISS) assembly will require 135 h x yr(-1) of EVA, and 138 h x yr(-1) is planned for post-construction maintenance. The extravehicular mobility unit (EMU), used to protect astronauts during EVA, has a decreased pressure of 4.3 psi that could increase astronauts' risk of decompression sickness (DCS). Exercise in and repeated exposure to this hypobaria may increase the incidence of DCS, although weightlessness may attenuate this risk. Exercise thermoregulation within the EMU is poorly understood; the liquid cooling garment (LCG), worn next to the skin and designed to handle thermal stress, is manually controlled. Astronauts may become dehydrated (by up to 2.6% of body weight) during a 5-h EVA, further exacerbating the thermoregulatory challenge. The EVA is performed mainly with upper body muscles; but astronauts usually exercise at only 26-32% of their upper body maximal oxygen uptake (VO2max). For a given ground-based work task in air (as opposed to water), the submaximal VO2 is greater while VO2max and metabolic efficiency are lower during ground-based arm exercise as compared with leg exercise, and cardiovascular responses to exercise and training are also different for arms and legs. Preflight testing and training, whether conducted in air or water, must account for these differences if ground-based data are extrapolated for flight requirements. Astronauts experience deconditioning during microgravity resulting in a 10-20% loss in arm strength, a 20-30% loss in thigh strength, and decreased lower-body aerobic exercise capacity. Data from ground-based simulations of weightlessness such as bed rest induce a 6-8% decrease in upper-body strength, a 10-16% loss in thigh extensor

  18. Journal of Gravitational Physiology, Volume 12, Number 1

    Science.gov (United States)

    Fuller, Charles A. (Editor); Cogoli, Augusto (Editor); Hargens, Alan R. (Editor); Smith, Arthur H. (Editor)

    2005-01-01

    The following topics were covered: System Specificity in Responsiveness to Intermittent -Gx Gravitation during Simulated Microgravity in Rats; A Brief Overview of Animal Hypergravity Studies; Neurovestibular Adaptation to Short Radius Centrifugation; Effect of Artificial Gravity with Exercise Load by Using Short-Arm Centrifuge with Bicycle Ergometer as a Countermeasure Against Disused Osteoporosis; Perception of Body Vertical in Microgravity during Parabolic Flight; Virtual Environment a Behavioral and Countermeasure Tool for Assisted Gesture in Weightlessness: Experiments during Parabolic Flight; Artificial Gravity: Physiological Perspectives for Long-Term Space Exploration; Comparison of the Effects of DL-threo-Beta-Benzyloxyaspartate on the Glutamate Release from Synaptosomes before and after Exposure of Rats to Artificial Gravity; Do Perception and Postrotatory Vestibulo-Ocular Reflex Share the Same Gravity Reference?; Vestibular Adaptation to Changing Gravity Levels and the Orientation of Listing's Plane; Compound Mechanism Hypothesis on +Gz - Induced Brain Injury and Dysfunction of Learning and Memory; Environmental Challenge Impairs Prefrontal Brain Functions; Effect of 6-Days of Support Withdrawal on Characteristics of Balance Function; Hypergravity-Induced Changes of Neuronal Activities in CA1 Region of Rat Hippocampus; Audiological Findings in Antiorthostatic Position Modelling Microgravitation; Investigating Human Cognitive Performance during Spaceflight; The Relevance of the Minimization of Torque Exchange with the Environment in Weightlessness is Confirmed by Asimulation Study; Characteristics of the Eyes Pursuit Function during Readaptation to Terrestrial Gravity after Prolonged Flights Aboard the International Space Station; Comparison of Cognitive Performance Tests for Promethazine Pharmacodynamics in Human Subjects; Structural Reappraisal of Dendritic Tree of Cerebellar Purkinje Cell for Novel Functional Modeling of Elementary Sensorimotor Adaptive

  19. The role of vestibular and support-tactile-proprioceptive inputs in visual-manual tracking

    Science.gov (United States)

    Kornilova, Ludmila; Naumov, Ivan; Glukhikh, Dmitriy; Khabarova, Ekaterina; Pavlova, Aleksandra; Ekimovskiy, Georgiy; Sagalovitch, Viktor; Smirnov, Yuriy; Kozlovskaya, Inesa

    Sensorimotor disorders in weightlessness are caused by changes of functioning of gravity-dependent systems, first of all - vestibular and support. The question arises, what’s the role and the specific contribution of the support afferentation in the development of observed disorders. To determine the role and effects of vestibular, support, tactile and proprioceptive afferentation on characteristics of visual-manual tracking (VMT) we conducted a comparative analysis of the data obtained after prolonged spaceflight and in a model of weightlessness - horizontal “dry” immersion. Altogether we examined 16 Russian cosmonauts before and after prolonged spaceflights (129-215 days) and 30 subjects who stayed in immersion bath for 5-7 days to evaluate the state of the vestibular function (VF) using videooculography and characteristics of the visual-manual tracking (VMT) using electrooculography & joystick with biological visual feedback. Evaluation of the VF has shown that both after immersion and after prolonged spaceflight there were significant decrease of the static torsional otolith-cervical-ocular reflex (OCOR) and simultaneous significant increase of the dynamic vestibular-cervical-ocular reactions (VCOR) with a revealed negative correlation between parameters of the otoliths and canals reactions, as well as significant changes in accuracy of perception of the subjective visual vertical which correlated with changes in OCOR. Analyze of the VMT has shown that significant disorders of the visual tracking (VT) occurred from the beginning of the immersion up to 3-4 day after while in cosmonauts similar but much more pronounced oculomotor disorders and significant changes from the baseline were observed up to R+9 day postflight. Significant changes of the manual tracking (MT) were revealed only for gain and occurred on 1 and 3 days in immersion while after spaceflight such changes were observed up to R+5 day postflight. We found correlation between characteristics

  20. International Space Station as Analog of Interplanetary Transit Vehicle For Biomedical Research

    Science.gov (United States)

    Charles, John B.

    2012-01-01

    Astronaut missions lasting up to six months aboard the International Space Station (ISS) have much in common with interplanetary flights, especially the outbound, Earth-to-Mars transit portion of a Mars mission. Utilization of ISS and other appropriate platforms to prepare for crewed expeditions to planetary destinations including Mars has been the work of NASA's Human Research Program (HRP) since 2005. HRP is charged specifically to understand and reduced the risks to astronaut health and performance in space exploration missions: everything HRP does and has done is directly related to that responsibility. Two major categories of human research have capitalized on ISS capabilities. The first category centers on the biomedical aspects of long-duration exposure to spaceflight factors, including prolonged weightlessness, radiation exposure, isolation and confinement, and actual risk to life and limb. These studies contribute to astronaut safety, health and efficiency on any long-duration missions, whether in low Earth orbit (LEO) or beyond. Qualitatively, weightlessness is weightlessness, whether in LEO or en route to Mars. The HRP sponsors investigations into losses in muscle and bone integrity, cardiovascular function, sensory-motor capability, immune capacity and psychosocial health, and development and demonstration of appropriate treatments and preventative measures. The second category includes studies that are focused on planetary expeditions beyond LEO. For these, ISS offers a high fidelity analog to investigate the combined effects of spaceflight factors (described above) plus the isolation and autonomy associated with simulated increasing distance from Earth. Investigations address crew cohesion, performance and workload, and mission control performance. The behavioral health and performance and space human factors aspects of planetary missions dominate this category. Work has already begun on a new investigation in this category which will examine the

  1. The exercise and environmental physiology of extravehicular activity

    Science.gov (United States)

    Cowell, Stephenie A.; Stocks, Jodie M.; Evans, David G.; Simonson, Shawn R.; Greenleaf, John E.

    2002-01-01

    Extravehicular activity (EVA), i.e., exercise performed under unique environmental conditions, is indispensable for supporting daily living in weightlessness and for further space exploration. From 1965-1996 an average of 20 h x yr(-1) were spent performing EVA. International Space Station (ISS) assembly will require 135 h x yr(-1) of EVA, and 138 h x yr(-1) is planned for post-construction maintenance. The extravehicular mobility unit (EMU), used to protect astronauts during EVA, has a decreased pressure of 4.3 psi that could increase astronauts' risk of decompression sickness (DCS). Exercise in and repeated exposure to this hypobaria may increase the incidence of DCS, although weightlessness may attenuate this risk. Exercise thermoregulation within the EMU is poorly understood; the liquid cooling garment (LCG), worn next to the skin and designed to handle thermal stress, is manually controlled. Astronauts may become dehydrated (by up to 2.6% of body weight) during a 5-h EVA, further exacerbating the thermoregulatory challenge. The EVA is performed mainly with upper body muscles; but astronauts usually exercise at only 26-32% of their upper body maximal oxygen uptake (VO2max). For a given ground-based work task in air (as opposed to water), the submaximal VO2 is greater while VO2max and metabolic efficiency are lower during ground-based arm exercise as compared with leg exercise, and cardiovascular responses to exercise and training are also different for arms and legs. Preflight testing and training, whether conducted in air or water, must account for these differences if ground-based data are extrapolated for flight requirements. Astronauts experience deconditioning during microgravity resulting in a 10-20% loss in arm strength, a 20-30% loss in thigh strength, and decreased lower-body aerobic exercise capacity. Data from ground-based simulations of weightlessness such as bed rest induce a 6-8% decrease in upper-body strength, a 10-16% loss in thigh extensor

  2. Nutrition and human physiological adaptations to space flight

    Science.gov (United States)

    Lane, H. W.; LeBlanc, A. D.; Putcha, L.; Whitson, P. A.

    1993-01-01

    Space flight provides a model for the study of healthy individuals undergoing unique stresses. This review focuses on how physiological adaptations to weightlessness may affect nutrient and food requirements in space. These adaptations include reductions in body water and plasma volume, which affect the renal and cardiovascular systems and thereby fluid and electrolyte requirements. Changes in muscle mass and function may affect requirements for energy, protein and amino acids. Changes in bone mass lead to increased urinary calcium concentrations, which may increase the risk of forming renal stones. Space motion sickness may influence putative changes in gastro-intestinal-hepatic function; neurosensory alterations may affect smell and taste. Some or all of these effects may be ameliorated through the use of specially designed dietary countermeasures.

  3. The TRIPLE LUX-A Experiment for BIOLAB/ISS- Combined Effects of Microgravity and Cosmic Radiation on the Oxidative Burst of Mammalian Macrophageal Cells

    Science.gov (United States)

    Huber, K.; Sromicki, J.; Hock, B.; Ullrich, O.

    2008-06-01

    Phagocytes, the prominent cells of innate immunity, are responsible for the removal of foreign invaders, apoptotic as well as cancer cells. In a flight experiment in the BIOLAB facility on the ISS we will investigate the combined effects of microgravity and cosmic radiation on the oxidative burst, the production of reactive oxygen species (ROS), of the macrophageal cell line NR8383. A chemiluminescence assay (luminol) is used to determine the amount of ROS during phagocytosis of zymosan in a kinetic approach. Ground control experiments for the TRIPLE LUX-A flight experiment on a fast rotating 2D clinostat showed that the selected cell line responds to simulated weightlessness by an increase of ROS production.

  4. Gravity Plant Physiology Facility (GPPF) Team in the Spacelab Payload Operations Control Center (SL

    Science.gov (United States)

    1992-01-01

    The primary payload for Space Shuttle Mission STS-42, launched January 22, 1992, was the International Microgravity Laboratory-1 (IML-1), a pressurized manned Spacelab module. The goal of IML-1 was to explore in depth the complex effects of weightlessness of living organisms and materials processing. Around-the-clock research was performed on the human nervous system's adaptation to low gravity and effects of microgravity on other life forms such as shrimp eggs, lentil seedlings, fruit fly eggs, and bacteria. Materials processing experiments were also conducted, including crystal growth from a variety of substances such as enzymes, mercury iodide, and a virus. The Huntsville Operations Support Center (HOSC) Spacelab Payload Operations Control Center (SL POCC) at the Marshall Space Flight Center (MSFC) was the air/ground communication channel used between the astronauts and ground control teams during the Spacelab missions. Featured is the Gravity Plant Physiology Facility (GPPF) team in the SL POCC during the IML-1 mission.

  5. Practical Applications of Cables and Ropes in the ISS Countermeasures System

    Science.gov (United States)

    Moore, Cherice; Svetlik, Randall; Williams, Antony

    2017-01-01

    As spaceflight durations have increased over the last four decades, the effects of weightlessness on the human body are far better understood, as are the countermeasures. A combination of aerobic and resistive exercise devices contribute to countering the losses in muscle strength, aerobic fitness, and bone strength of today's astronauts and cosmonauts that occur during their missions on the International Space Station. Creation of these systems has been a dynamically educational experience for designers and engineers. The ropes and cables in particular have experienced a wide range of challenges, providing a full set of lessons learned that have already enabled improvements in on-orbit reliability by initiating system design improvements. This paper examines the on-orbit experience of ropes and cables in several exercise devices and discusses the lessons learned from these hardware items, with the goal of informing future system design.

  6. Ultrasonic wave interactions with magnetic colloids

    CERN Document Server

    Chapman, J R

    2001-01-01

    fluids have been performed in an effort to determine the relative stability of the fluids. The experimental results have been compared with a combined scattering and hydrodynamic model (Allegra and Hawley 1972) and the ultrasonic anisotropy theory of Skumiel (1997). An on-line quality assurance process is proposed. Originally invented as a method for moving spacecraft fuel in weightless conditions, magnetic colloids or ferrofluids are now used in applications as diverse as the dissipation of heat in the voice coils of a loudspeaker, and for the separation of scrap metal. It has been found that aqueous ferrofluids become unstable after a period of time and with dilution. Therefore, there is a need to characterize the colloidal fluid to study the effects of degradation. Additionally, due to the high cost of ferrofluids and the large volumes required for some applications, the fluid is recycled. It is therefore necessary to develop a system for quality assurance for the fluid reclamation process. Ultrasonic meth...

  7. Liquid-bridge breakup in contact-drop dispensing: Liquid-bridge stability with a free contact line

    Science.gov (United States)

    Akbari, Amir; Hill, Reghan J.; van de Ven, Theo G. M.

    2015-08-01

    The static stability of weightless liquid bridges with a free contact line with respect to axisymmetric and nonaxisymmetric perturbations is studied. Constant-volume and constant-pressure stability regions are constructed in slenderness versus cylindrical volume diagrams for fixed contact angles. Bifurcations along the stability-region boundaries are characterized by the structure of axisymmetric bridge branches and families of equilibria. A wave-number definition is presented based on the pieces-of-sphere states at branch terminal points to classify equilibrium branches and identify branch connections. Compared with liquid bridges pinned at two equal disks, the free contact line breaks the equatorial and reflective symmetries, affecting the lower boundary of the constant-volume stability region where axisymmetric perturbations are critical. Stability is lost at transcritical bifurcations and turning points along this boundary. Our results furnish the maximum-slenderness stability limit for drop deposition on real surfaces when the contact angle approaches the receding contact angle.

  8. Fluid shifts, vasodilatation and ambulatory blood pressure reduction during long duration spaceflight

    DEFF Research Database (Denmark)

    Norsk, Peter; Asmar, Ali; Damgaard, Morten;

    2015-01-01

    KEY POINTS: Weightlessness in space induces initially an increase in stroke volume and cardiac output, accompanied by unchanged or slightly reduced blood pressure.It is unclear whether these changes persist throughout months of flight.Here, we show that cardiac output and stroke volume increase...... by 35–41% between 3 and 6 months on the International Space Station, which is more than during shorter flights.Twenty-four hour ambulatory brachial blood pressure is reduced by 8–10 mmHg by a decrease in systemic vascular resistance of 39%, which is not a result of the suppression of sympathetic nervous...... brachial arterial pressures were automatically recorded at 1–2 h intervals with portable equipment in eight male astronauts: once before launch, once between 85 and 192 days in space on the International Space Station and, finally, once at least 2 months after flight. During the same 24 h, cardiac output...

  9. Adaptive response of slow and fast skeletal muscle in the monkey to spaceflight

    Science.gov (United States)

    Bodine-Fowler, Sue

    1996-01-01

    Experiments were designed to determine the effects of the absence of weight support on hindlimb muscles of the monkey: an ankle flexor (tibialis anterior, TA), two ankle extensors (medical gastrocnemius, MG and soleus, SOL), and a knee extensor (vastus lateralis, VL). These experiments will be performed as part of the BION mission. The original project proposed to assess the effects of weightlessness in adult Rhesus monkeys which were to be flown on the Space Shuttle as part of SLS-3. Feasibility studies were carried out and a series of experiments were performed at NASA/Ames Research Center to assess the effects of a 21-day restraint period in the ESOP on muscle properties. The results of these studies are summarized.

  10. Research progress in the mechanism of disuse osteoporosis%废用性骨质疏松症发病机制的研究进展

    Institute of Scientific and Technical Information of China (English)

    朱生根; 廖玉兰

    2013-01-01

    The reason for disuse osteoporosis is systemic or partial bone mineral loss due to limited exercise capacity, dysfunction, and weightlessness.But its mechanism is still unclear.This paper reviews the related literatures on the mechanism of disuse osteoporosis in recent years.%废用性骨质疏松症发病原因是由于运动能力受限、功能障碍和失重而引起全身或局部骨矿物含量增减少所致,但其病理机制仍不十分清楚,笔者就近年来的相关研究文献对废用性骨质疏松症发病机制作一综述。

  11. On-Demand Urine Analyzer

    Science.gov (United States)

    Farquharson, Stuart; Inscore, Frank; Shende, Chetan

    2010-01-01

    A lab-on-a-chip was developed that is capable of extracting biochemical indicators from urine samples and generating their surface-enhanced Raman spectra (SERS) so that the indicators can be quantified and identified. The development was motivated by the need to monitor and assess the effects of extended weightlessness, which include space motion sickness and loss of bone and muscle mass. The results may lead to developments of effective exercise programs and drug regimes that would maintain astronaut health. The analyzer containing the lab-on-a- chip includes materials to extract 3- methylhistidine (a muscle-loss indicator) and Risedronate (a bone-loss indicator) from the urine sample and detect them at the required concentrations using a Raman analyzer. The lab-on- a-chip has both an extractive material and a SERS-active material. The analyzer could be used to monitor the onset of diseases, such as osteoporosis.

  12. "Anti-Gravity" Treadmills Speed Rehabilitation

    Science.gov (United States)

    2009-01-01

    A former Ames Research Center engineer, Dr. Robert Whalen, invented a treadmill that he licensed to a Menlo Park, California company, Alter-G Inc. The company s G-Trainer is an enclosed treadmill that uses air pressure to help patients feel up to 80 percent lighter, easing discomfort during rehabilitation. A patient desiring more weightlessness during a workout can simply press a button and the air pressure increases, lifting the body and reducing strain and impact. The U.S. Food and Drug Administration cleared the G-Trainer for medical use in January 2008, and researchers are now assessing the G-Trainer s effectiveness in aiding patients with various neurological or musculoskeletal conditions.

  13. Space and Ground-Based Infrastructures

    Science.gov (United States)

    Weems, Jon; Zell, Martin

    This chapter deals first with the main characteristics of the space environment, outside and inside a spacecraft. Then the space and space-related (ground-based) infrastructures are described. The most important infrastructure is the International Space Station, which holds many European facilities (for instance the European Columbus Laboratory). Some of them, such as the Columbus External Payload Facility, are located outside the ISS to benefit from external space conditions. There is only one other example of orbital platforms, the Russian Foton/Bion Recoverable Orbital Capsule. In contrast, non-orbital weightless research platforms, although limited in experimental time, are more numerous: sounding rockets, parabolic flight aircraft, drop towers and high-altitude balloons. In addition to these facilities, there are a number of ground-based facilities and space simulators, for both life sciences (for instance: bed rest, clinostats) and physical sciences (for instance: magnetic compensation of gravity). Hypergravity can also be provided by human and non-human centrifuges.

  14. Prediction of femoral neck and spine bone mineral content from the BMC of the radius or ulna and the relationship between bone strength and BMC

    Science.gov (United States)

    Wilson, C. R.

    1974-01-01

    The bone mineral content (BMC) is extensively used to provide information about the status of an entire skeleton. Changes in BMC are employed to evaluate the effect of various drugs, disease states, weightlessness, exercise, renal dialysis and others on the skeleton. Clinical and functional information is discussed that may be derived from the BMC of a limited region of the skeleton. In particular there is a fairly high degree of correlation between the BMC of the radius or ulna and that of the femoral neck, r about 0.85 and a somewhat lower relationship between the BMC of the radius or ulna and the thoracic vertebrae, r about 0.65. Also the BMC is highly related to the strength of bone at that scan site.

  15. Preliminary results of scientific research on biosatellite KOSMOS-1129

    Energy Technology Data Exchange (ETDEWEB)

    1980-08-01

    The first physiological study aimed at deeper examination mechanisms of weightlessness and adaptation/readaptation is described. It dealt with metabolism, support motor changes and nonspecific changes connected with stress reaction. Wistar rats were used in a triple setup: flight/vivarium/biosatellite mockup. Animal condition was assessed on motor activity and body temperature. Extensive tables show weight, blood and enzyme analysis, etc. Animals groups were labeled: stress, behavior, body composition, biorhythm, ontogenesis. The second or biological study dealt with tumorous carrot tissues but humidity control was defective: some indices are reported such as cell membrane permeability, tissue respiration, etc. It also was concerned with a fowl embryogenetic experiment (Japanese quail) but mechanical effects on landing reduced its success. The third study, on radiation dosimetry, presents a little tabulated data but chiefly gives lists of satellite detector units of different kinds and from different countries.

  16. Magnetic Field, Force, and Inductance Computations for an Axially Symmetric Solenoid

    Science.gov (United States)

    Lane, John E.; Youngquist, Robert C.; Immer, Christopher D.; Simpson, James C.

    2001-01-01

    The pumping of liquid oxygen (LOX) by magnetic fields (B field), using an array of electromagnets, is a current topic of research and development at Kennedy Space Center, FL. Oxygen is paramagnetic so that LOX, like a ferrofluid, can be forced in the direction of a B field gradient. It is well known that liquid oxygen has a sufficient magnetic susceptibility that a strong magnetic gradient can lift it in the earth's gravitational field. It has been proposed that this phenomenon can be utilized in transporting (i.e., pumping) LOX not only on earth, but on Mars and in the weightlessness of space. In order to design and evaluate such a magnetic pumping system, it is essential to compute the magnetic and force fields, as well as inductance, of various types of electromagnets (solenoids). In this application, it is assumed that the solenoids are air wrapped, and that the current is essentially time independent.

  17. Adiabatic heating and convection in a porous medium filled with a near-critical fluid.

    Science.gov (United States)

    Soboleva, E B

    2009-04-01

    Dynamics and heat transfer in a porous medium filled with a fluid phase at parameters near the gas-liquid critical point are studied. A two-dimensional numerical solver based on the hydrodynamic model for a porous medium with a high compressible fluid phase including the van der Waals equation of state is used. In weightlessness, adiabatic heating of fluid phase under the step-temperature heat supply is investigated analytically and numerically. In terrestrial conditions, gravity-driven convection in vertical rectangular cells generated by lateral heating in unsteady and steady-state regimes is simulated. The effects of high compressibility of near-critical fluid phase on convection are studied. Convective motions and heat transfer in horizontal rectangular cells consisting of two porous layers at different porosity and permeability heated from below are simulated as well. Adiabatic heating subjected to hydrostatic compressibility effects, the onset and development of convection, and convective structures in a steady-state regime are analyzed.

  18. Stability of metallic foams studied under microgravity

    Energy Technology Data Exchange (ETDEWEB)

    Wuebben, Th [University of Bremen (Germany); Stanzick, H [Fraunhofer-Institute (IFAM), Bremen (Germany); Banhart, J [Hahn-Meitner-Institute Berlin, (Germany); Odenbach, S [University of Bremen (Germany)

    2003-01-15

    Metal foams are prepared by mixing a metal powder and a gas-releasing blowing agent, by densifying the mix to a dense precursor and finally foaming by melting the powder compact. The foaming process of aluminium foams is monitored in situ by x-ray radioscopy. One observes that foam evolution is accompanied by film rupture processes which lead to foam coalescence. In order to elucidate the importance of oxides for foam stability, lead foams were manufactured from lead powders having two different oxide contents. The two foam types were generated on Earth and under weightlessness during parabolic flights. The measurements show that the main function of oxide particles is to prevent coalescence, while their influence on bulk viscosity of the melt is of secondary importance.

  19. Nutritional studies

    Science.gov (United States)

    Rambaut, P. C.; Smith, M. C., Jr.; Wheeler, H. O.

    1975-01-01

    Detailed metabolic studies were conducted of the Apollo 16 and Apollo 17 flight crews, and the results are presented in tabular form. Intake and absorption data are also included. Apollo nutrient intakes were found to be characteristically hypocaloric. Estimates of body composition changes from metabolic balance data, from preflight and postflight weights and volumes, and from total body water and potassium provide no evidence for diminished caloric requirements during a flight. As observed during the Gemini Program and during periods of bed rest, measurements of bone density and metabolic balance confirm a tendency toward loss of skeletal tissue in weightlessness. No evidence exists that any inflight metabolic anomaly, including hypokalemia, was induced by marginal or deficient nutrient intakes. In general, the Apollo crewmen were well nourished and exhibited normal gastroenterological functions, although appetite was somewhat diminished and the organoleptic response to food was somewhat modified during flight.

  20. Capillary channel flow experiments aboard the International Space Station

    Science.gov (United States)

    Conrath, M.; Canfield, P. J.; Bronowicki, P. M.; Dreyer, M. E.; Weislogel, M. M.; Grah, A.

    2013-12-01

    In the near-weightless environment of orbiting spacecraft capillary forces dominate interfacial flow phenomena over unearthly large length scales. In current experiments aboard the International Space Station, partially open channels are being investigated to determine critical flow rate-limiting conditions above which the free surface collapses ingesting bubbles. Without the natural passive phase separating qualities of buoyancy, such ingested bubbles can in turn wreak havoc on the fluid transport systems of spacecraft. The flow channels under investigation represent geometric families of conduits with applications to liquid propellant acquisition, thermal fluids circulation, and water processing for life support. Present and near future experiments focus on transient phenomena and conduit asymmetries allowing capillary forces to replace the role of gravity to perform passive phase separations. Terrestrial applications are noted where enhanced transport via direct liquid-gas contact is desired.

  1. Gravity and the cells of gravity receptors in mammals

    Science.gov (United States)

    Ross, M. D.

    1983-01-01

    A model of the mammalian gravity receptor system is presented, with attention given to the effects of weightlessness. Two receptors are on each side of the head, with end organs in the saccule and utricle of the vestibular membranous labyrinth of the inner ear, embedded in the temporal bone. Each end organ has a macula, containing hair cells and supporting cells, and an otoconial complex, an otoconial membrane and mineral masses called otoconia. X ray powder diffraction examinations have revealed that the otoconia can behave like crystals, i.e., with piezoelectric properties, due to the mineral deposits. Bending of the hair cells because of acceleration can put pressure on the otoconial mineral, producing an electrical signal in the absence of a gravitational field. The possibility that pyroelectricity, as well as piezoelectricity, is present in the otoconial complexes, is discussed.

  2. Effects of High Magneto-Gravitational Environment on Silkworm Embryogenesis

    Science.gov (United States)

    Tian, Zongcheng; Li, Muwang; Qian, Airong; Xu, Huiyun; Wang, Zhe; Di, Shengmeng; Yang, Pengfei; Hu, Lifang; Ding, Chong; Zhang, Wei; Luo, Mingzhi; Han, Jing; Gao, Xiang; Huang, Yongping; Shang, Peng

    2010-04-01

    The objective of this research was to observe whether silkworm embryos can survive in a high magneto-gravitational environment (HMGE) and what significant phenotype changes can be produced. The hatching rate, hatching time, life span, growth velocity and cocoon weight of silkworm were measured after silkworm embryos were exposed to HMGE (0 g, 12 T; 1 g, 16 T; and 2 g, 12 T) for a period of time. Compared with the control group, 0 g exposure resulted in a lower hatching rate and a shorter life span. Statistically insignificant morphological changes had been observed for larvae growth velocity, incidence of abnormal markings and weight of cocoons. These results suggest that the effect of HMGE on silkworm embryogenesis is not lethal. Bio-effects of silkworm embryogenesis at 0 g in a HMGE were similar with those of space flight. The hatching time, life span and hatching rates of silkworm may be potential phenotype markers related to exposure in a weightless environment.

  3. Seismic bearing capacity of strip footings on rock masses using the Hoek–Brown failure criterion

    Directory of Open Access Journals (Sweden)

    Amin Keshavarz

    2016-04-01

    Full Text Available In this paper, the bearing capacity of strip footings on rock masses has been studied in the seismic case. The stress characteristics or slip line method was used for analysis. The problem was analyzed in the plane strain condition using the Hoek–Brown failure criterion. First, the equilibrium equations along the stress characteristics were obtained and the rock failure criterion was applied. Then, the equations were solved using the finite difference method. A computer code has been provided for analysis. Given the footing and rock parameters, the code can calculate the stress characteristics network and obtain the stress distribution under the footing. The seismic effects have been applied as the horizontal and vertical pseudo-static coefficients. The results of this paper are very close to those of the other studies. The seismic bearing capacity of weightless rock masses can be obtained using the proposed equations and graphs without calculating the whole stress characteristics network.

  4. Advantages of adopting the operational definition of weight

    CERN Document Server

    Figueiredo, J M L

    2005-01-01

    With rare exceptions, in high school and college/university physics courses literature and in journals of physics, the weight is defined as a gravitational force or an exclusive consequence of it. These definitions lack logic from the perspective of present knowledge and can be misleading. The operational definition of weight of a body as the force the body exerts on its support or suspender can eliminate the ambiguities associated to "true weight", "apparent weight", "state of weightlessness", "zero weight", "zero gravity", "microgravity", "vertical", "up" and "down". Nevertheless, the concept of weight of a body is not fundamental in Physics and its exclusion from the physics vocabulary will eliminate some of former concepts or their ambiguousness with evident benefit for physics teaching and learning. This paper discusses weight of a body concepts and presents several examples that show the advantages of avoiding its use or adopting the above-mentioned operational definition. It is believed that this will ...

  5. Immersion diuresis without expected suppression of vasopressin

    Science.gov (United States)

    Keil, L. C.; Silver, J. E.; Wong, N.; Spaul, W. A.; Greenleaf, J. E.; Kravik, S. E.

    1984-01-01

    There is a shift of blood from the lower parts of the body to the thoracic circulation during bed rest, water immersion, and presumably during weightlessness. On earth, this central fluid shift is associated with a profound diuresis. However, the mechanism involved is not yet well understood. The present investigation is concerned with measurements regarding the plasma vasopressin, fluid, electrolyte, and plasma renin activity (PRA) responses in subjects with normal preimmersion plasma vasopressin (PVP) concentration. In the conducted experiments, PRA was suppressed significantly at 30 min of immersion and had declined by 74 percent by the end of the experiment. On the basis of previously obtained results, it appears that sodium excretion during immersion may be independent of aldosterone action. Experimental results indicate that PVP is not suppressed by water immersion in normally hydrated subjects and that other factors may be responsible for the diuresis.

  6. Alterations in Skeletal Muscle Microcirculation of Head-Down Tilted Rats

    Science.gov (United States)

    Musacchia, X. J.; Stepke, Bernhard; Fleming, John T.; Joshua, Irving G.

    1992-01-01

    In this study we assessed the function of microscopic blood vessels in skeletal muscle (cremaster muscle) for alterations which may contribute to the observed elevation of blood pressure associated with head-down tilted whole body suspension (HDT/WBS), a model of weightlessness. Arteriolar baseline diameters, vasoconstrictor responses to norepinephrine (NE) and vasodilation to nitroprusside (NP) were assessed in control rats, rats suspended for 7 or 14 day HDT/WBS rats, and rats allowed to recover for 1 day after 7 days HDT/WBS. Neither baseline diameters nor ability to dilate were influenced by HDT/WBS. Maximum vasoconstriction to norepinephrine was significantly greater in arterioles of hypertensive 14 day HDT/WBS rats. This first study of the intact microvasculature in skeletal muscle indicates that an elevated contractility of arterioles to norepinephrine in suspended rats, and suggests an elevated peripheral resistance in striated muscle may contribute to the increase in blood pressures among animals subjected to HDT/WBS.

  7. Locomotor problems of supersonic aviation and astronautics.

    Science.gov (United States)

    Remes, P

    1989-04-01

    Modern high-speed aviation and space flight are fraught with many problems and require a high standard of health and fitness. Those responsible for the health of pilots must appreciate the importance of early diagnosis even before symptoms appear. This is particularly true in terms of preventing spinal injuries where even a single Schmorl's node may make a pilot unfit for high-speed flying. Spinal fractures are frequent during emergency ejection and landing. Helicopter crews are particularly prone to spinal disc degeneration due to vibration. By effective lowering of vibration by changes in the seats, a reduction in such lesions is possible. The osteoporosis and muscle atrophy occurring among astronauts subjected to prolonged weightlessness can be prevented by regular physical exercises.

  8. Proposed application of lower body negative pressure to cardiology

    Science.gov (United States)

    Schmidt, E. V.; Debusk, R. F.; Popp, R. L.

    1975-01-01

    Potential medical applications are presented of lower body negative pressure to the evaluation and treatment of cardiac patients. The essential features of an LBNP unit and the basic cardiovascular physiology of lower body negative pressure (LBNP) testing are described. Some of the results of previous spaceflight experiences and bedrest studies are summarized. The deconditioning effects of weightlessness experienced by orbiting astronauts are compared with the effects of bedrest restrictions prescribed for convalescing cardiac patients. The potential of LBNP for evaluating both pharmacological and physical activity regimens was examined, particularly in relation to post-myocardial infarction and coronary artery bypass patients. Applications of LBNP to the cardiac catheterization laboratory and the out-patient follow-up of cardiac patients are proposed.

  9. An integrative approach to space-flight physiology using systems analysis and mathematical simulation

    Science.gov (United States)

    Leonard, J. I.; White, R. J.; Rummel, J. A.

    1980-01-01

    An approach was developed to aid in the integration of many of the biomedical findings of space flight, using systems analysis. The mathematical tools used in accomplishing this task include an automated data base, a biostatistical and data analysis system, and a wide variety of mathematical simulation models of physiological systems. A keystone of this effort was the evaluation of physiological hypotheses using the simulation models and the prediction of the consequences of these hypotheses on many physiological quantities, some of which were not amenable to direct measurement. This approach led to improvements in the model, refinements of the hypotheses, a tentative integrated hypothesis for adaptation to weightlessness, and specific recommendations for new flight experiments.

  10. Gravity related behavior of the acellular slime mold Physarum polycephalum (7-IML-1)

    Science.gov (United States)

    Block, I.

    1992-01-01

    The objective of the experiment is to investigate the effect of near weightlessness on a single cell. The test object is the acellular slime mold Physarum polycephalum. This cell is composed of a network of protoplastic strands which perform rhythmic contractions in the minute range. These contractions of the strands' ectoplastic walls generate the force to drive the vigorous shuttle streaming of fluid protoplasm inside the strands (hydrostatic pressure flow). A net transport of protoplasm in one direction determines the direction of the cell's locomotion itself. In this way, gravity modifies the contraction rhythm of the strands, the streaming velocity of protoplasm in the strands, and the direction of locomotion of the whole slime mold (geotaxis). The other parts of this experiment will address the major question of how this cell, which does not possess any specialized gravireceptors, gets the information about the direction of the gravity vector. Details of the experimental setup are given.

  11. Involvement of the second messenger cAMP in gravity-signal transduction in physarum

    Science.gov (United States)

    Block, I.; Rabien, H.; Ivanova, K.

    The aim of the investigation was to clarify, whether cellular signal processing following graviperception involves second messenger pathways. The test object was a most gravisensitive free-living ameboid cell, the myxomycete (acellular slime mold) Physarum polycephalum. It was demonstrated that the motor response is related to acceleration-dependent changes in the levels of the cellular second messenger cyclic adenosine monophosphate (cAMP). Rotating Physarum plasmodia in the gravity field of the Earth about a horizontal axis increased their cAMP concentration. Depriving the cells for a few days of the acceleration stimulus (near weightlessness in a space experiment on STS-69) slightly lowered plasmodial cAMP levels. Thus, the results provide first indications that the acceleration-stimulus signal transduction chain of Physarum uses an ubiquitous second messenger pathway.

  12. USSR Space Life Sciences Digest, issue 21

    Science.gov (United States)

    Hooke, Lydia Razran; Donaldson, P. Lynn; Garshnek, Victoria; Rowe, Joseph

    1989-01-01

    This is the twenty-first issue of NASA's USSR Space Life Sciences Digest. It contains abstracts of 37 papers published in Russian language periodicals or books or presented at conferences and of a Soviet monograph on animal ontogeny in weightlessness. Selected abstracts are illustrated with figures and tables from the original. A book review of a work on adaptation to stress is also included. The abstracts in this issue have been identified as relevant to 25 areas of space biology and medicine. These areas are: adaptation, biological rhythms, body fluids, botany, cardiovascular and respiratory systems, cytology, developmental biology, endocrinology, enzymology, equipment and instrumentation, exobiology, gravitational biology, habitability and environmental effects, hematology, human performance, life support systems, mathematical modeling, metabolism, microbiology, musculoskeletal system, neurophysiology, operational medicine, perception, psychology, and reproductive system.

  13. Capillary channel flow experiments aboard the International Space Station.

    Science.gov (United States)

    Conrath, M; Canfield, P J; Bronowicki, P M; Dreyer, M E; Weislogel, M M; Grah, A

    2013-12-01

    In the near-weightless environment of orbiting spacecraft capillary forces dominate interfacial flow phenomena over unearthly large length scales. In current experiments aboard the International Space Station, partially open channels are being investigated to determine critical flow rate-limiting conditions above which the free surface collapses ingesting bubbles. Without the natural passive phase separating qualities of buoyancy, such ingested bubbles can in turn wreak havoc on the fluid transport systems of spacecraft. The flow channels under investigation represent geometric families of conduits with applications to liquid propellant acquisition, thermal fluids circulation, and water processing for life support. Present and near future experiments focus on transient phenomena and conduit asymmetries allowing capillary forces to replace the role of gravity to perform passive phase separations. Terrestrial applications are noted where enhanced transport via direct liquid-gas contact is desired.

  14. Changes in blood volume and response to vaso-active drugs in horizontally casted primates

    Science.gov (United States)

    Dickey, D. T.; Teoh, K. K.; Sandler, H.; Stone, H. L.

    1982-01-01

    Experiments were performed on horizontally casted primates (male rhesus monkeys) in order to note changes in blood volume caused by horizontal restraint, to compare orthostatic tolerance before and after casting using the responses to upright tilting, to begin to uncover the cardiovascular and neural mechanisms involved in deconditioning, and to compare the data with that obtained from bed-rested human subjects and from humans exposed to weightlessness. Bolus injections of norepinephrine of 2.0 microgram/kg, phenylephrine of 4.0 microgram/kg, and nitroprusside of 2.0 microgram/kg were administered; and aortic pressure and heart rate were recorded during the injections. The results indicate that the horizontally casted primate is a valid animal model for studying the effects of simulated zero-G on the human cardiovascular system.

  15. Alterations in mitochondria and sarcoplasmic reticulum from heart and skeletal muscle of horizontally casted primates

    Science.gov (United States)

    Sordahl, L. A.; Stone, H. L.

    1982-01-01

    Horizontally body-casted rhesus monkeys are used as an animal model in order to study the physiological changes known as cardiovascular deconditioning which occur during weightless conditions. No difference was found between the experimental and control animals in heart mitochondrial oxidative phosphorylation which indicates that no apparent changes occurred in the primary energy-producing system of the heart. A marked increase in cytochrome oxidase activity was observed in the casted primate heart mitochondria compared to controls, while a 25% decrease in respiratory substrate-supported calcium uptake was found in casted primate heart mitochondria compared to controls. Sacroplasmic reticulum isolated from the primate hearts revealed marked changes in calcium transport activities. It is concluded that the marked depression in cardiac sarcoplasmic reticulum functions indicates altered calcium homeostasis in the casted-primate heart which could be a factor in cardiovascular deconditioning.

  16. First Middle East Aircraft Parabolic Flights for ISU Participant Experiments

    Science.gov (United States)

    Pletser, Vladimir; Frischauf, Norbert; Cohen, Dan; Foster, Matthew; Spannagel, Ruven; Szeszko, Adam; Laufer, Rene

    2017-02-01

    Aircraft parabolic flights are widely used throughout the world to create microgravity environment for scientific and technology research, experiment rehearsal for space missions, and for astronaut training before space flights. As part of the Space Studies Program 2016 of the International Space University summer session at the Technion - Israel Institute of Technology, Haifa, Israel, a series of aircraft parabolic flights were organized with a glider in support of departmental activities on `Artificial and Micro-gravity' within the Space Sciences Department. Five flights were organized with manoeuvres including several parabolas with 5 to 6 s of weightlessness, bank turns with acceleration up to 2 g and disorientation inducing manoeuvres. Four demonstration experiments and two experiments proposed by SSP16 participants were performed during the flights by on board operators. This paper reports on the microgravity experiments conducted during these parabolic flights, the first conducted in the Middle East for science and pedagogical experiments.

  17. A study of stress-free living bone and its application to space flight

    Science.gov (United States)

    Leblanc, A.; Spira, M.

    1983-01-01

    Observations of animals and human subjects in weightless space flight (Skylab and COSMOS) document altered bone metabolism. Bone metabolism is affected by a number of local and systemic factors. The calcification and growth of transplanted bone is independent of local muscle, nervous, and mechanical forces; therefore, transplanted bone would provide data on the role of local vs. systematic factors. Bone metabolism in living transplanted bone, devoid of stress, was investigated as a possible tool for the investigation of countermeasures against disuse bone loss. An animal model using Sprague-Dawley rats was developed for transplantation of femur bone tissue on a nutrient vascular pedicel. The long term course of these implants was assessed through the measure of regional and total bone mineral, blood flow, and methylene diphosphonate (MDP) uptake. Clomid, an estrogen agonist/antagonist, was shown to protect bone from disuse loss of minerals by retarding trabecular and cortical resorption.

  18. A new rat model for studies of hypokinesia and antiorthostasis

    Science.gov (United States)

    Musacchia, X. J.; Deavers, D. R.

    1982-01-01

    A new rat model (suspension and immobilization) is described for induction of hypokinesia and orthostatic manipulations. Hypokinetic responses were comparable to those in prolonged bed rest and weightlessness in humans, body or limb casted and small cage restrained animals. Responses to antiorthostasis (15 to 20 deg head down tilt) in rats were similar to those in neutral bouyancy tests in humans and animals and to those in prolonged bed rest in humans. During seven days of hypokinesia there was an atrophy of the gastrocnemius and increased excretion of urinary nitrogeneous end products. The antiorthostatic (AOH) 15 to 20 deg head down tilt resulted in diuresis, natriuresis and kaliuresis. No comparable responses were observed in orthostatic hypokinetic (OH) rats. Readaptation from AOH and OH occurred during one week recovery in metabolic cage conditions.

  19. Drug stability analyzer for long duration spaceflights

    Science.gov (United States)

    Shende, Chetan; Smith, Wayne; Brouillette, Carl; Farquharson, Stuart

    2014-06-01

    Crewmembers of current and future long duration spaceflights require drugs to overcome the deleterious effects of weightlessness, sickness and injuries. Unfortunately, recent studies have shown that some of the drugs currently used may degrade more rapidly in space, losing their potency well before their expiration dates. To complicate matters, the degradation products of some drugs can be toxic. Consequently there is a need for an analyzer that can determine if a drug is safe at the time of use, as well as to monitor and understand space-induced degradation, so that drug types, formulations, and packaging can be improved. Towards this goal we have been investigating the ability of Raman spectroscopy to monitor and quantify drug degradation. Here we present preliminary data by measuring acetaminophen, and its degradation product, p-aminophenol, as pure samples, and during forced degradation reactions.

  20. Drug stability analysis by Raman spectroscopy.

    Science.gov (United States)

    Shende, Chetan; Smith, Wayne; Brouillette, Carl; Farquharson, Stuart

    2014-12-22

    Pharmaceutical drugs are available to astronauts to help them overcome the deleterious effects of weightlessness, sickness and injuries. Unfortunately, recent studies have shown that some of the drugs currently used may degrade more rapidly in space, losing their potency before their expiration dates. To complicate matters, the degradation products of some drugs can be toxic. Here, we present a preliminary investigation of the ability of Raman spectroscopy to quantify mixtures of four drugs; acetaminophen, azithromycin, epinephrine, and lidocaine, with their primary degradation products. The Raman spectra for the mixtures were replicated by adding the pure spectra of the drug and its degradant to determine the relative percent contributions using classical least squares. This multivariate approach allowed determining concentrations in ~10 min with a limit of detection of ~4% of the degradant. These results suggest that a Raman analyzer could be used to assess drug potency, nondestructively, at the time of use to ensure crewmember safety.

  1. Drug Stability Analysis by Raman Spectroscopy

    Directory of Open Access Journals (Sweden)

    Chetan Shende

    2014-12-01

    Full Text Available Pharmaceutical drugs are available to astronauts to help them overcome the deleterious effects of weightlessness, sickness and injuries. Unfortunately, recent studies have shown that some of the drugs currently used may degrade more rapidly in space, losing their potency before their expiration dates. To complicate matters, the degradation products of some drugs can be toxic. Here, we present a preliminary investigation of the ability of Raman spectroscopy to quantify mixtures of four drugs; acetaminophen, azithromycin, epinephrine, and lidocaine, with their primary degradation products. The Raman spectra for the mixtures were replicated by adding the pure spectra of the drug and its degradant to determine the relative percent contributions using classical least squares. This multivariate approach allowed determining concentrations in ~10 min with a limit of detection of ~4% of the degradant. These results suggest that a Raman analyzer could be used to assess drug potency, nondestructively, at the time of use to ensure crewmember safety.

  2. Human otolith function, experiment M009

    Science.gov (United States)

    Graybiel, A.; Miller, E. F., II

    1971-01-01

    The experiments that were performed during the Gemini 5 and 7 missions resulted in quantitative information concerning otolithic function and orientation of four subjects exposed to an orbiting spacecraft environment for prolonged periods of time. Preflight counterrolling measurements revealed significant differences between crewmembers with regard to the basic magnitude of otolith response. However, after the flight, each crewmember maintained his respective preflight level of response. This was indicative that no significant change in otolithic sensitivity occurred as a result of the flight, or at least no change persisted long enough to be recorded several hours after recovery. The EVLH data recorded for each subject confirmed the observation that a coordinate space sense exists even in a weightless environment if contact cues are adequate. However, it was noted that the apparent location of the horizontal within the spacecraft may not agree necessarily with its physical correlate in the spacecraft.

  3. Experiment M131. Human vestibular function

    Science.gov (United States)

    Graybiel, A.; Miller, E. F., II; Homick, J. L.

    1977-01-01

    The lower susceptibility to vestibular stimulation aloft, compared with that on ground under experimental conditions, is attributed to a precondition, namely, either there is no need to adapt, or, as exemplified by the Skylab 3 pilot, adaptation to weightlessness is achieved. Findings in some of the astronauts emphasize the distinction between two categories of vestibular side effects: immediate reflex phenomena (illusions, sensations of turning, etc.), and delayed epiphenomena that include the constellation of symptoms and syndromes comprising motion sickness. The drug combinations 1-scopolamine and d-amphetamine and promethazine hydrochloride and ephedrine sulfate are effective in prevention and treatment of motion sickness. It is concluded that prevention of motion sickness in any stressful motion environment involves selection, adaptation, and the use of drugs.

  4. Body acceleration distribution and O2 uptake in humans during running and jumping

    Science.gov (United States)

    Bhattacharya, A.; Mccutcheon, E. P.; Shvartz, E.; Greenleaf, J. E.

    1980-01-01

    The distribution of body acceleration and associated oxygen uptake and heart rate responses are investigated in treadmill running and trampoline jumping. Accelerations in the +Gz direction were measured at the lateral ankle, lumbosacral region and forehead of eight young men during level treadmill walking and running at four speeds and trampoline jumping at four heights, together with corresponding oxygen uptake and heart rate. With increasing treadmill speed, peak acceleration at the ankle is found always to exceed that at the back and forehead, and acceleration profiles with higher frequency components than those observed during jumping are observed. Acceleration levels are found to be more uniformly distributed with increasing height in jumping, although comparable oxygen uptake and heat rates are obtained. Results indicate that the magnitude of the biomechanical stimuli is greater in trampoline jumping than in running, which finding could be of use in the design of procedures to avert deconditioning in persons exposed to weightlessness.

  5. Structural Assembly Demonstration Experiment (SADE) experiment design

    Science.gov (United States)

    Akin, D. L.; Bowden, M. L.

    1982-03-01

    The Structural Assembly Demonstration Experiment concept is to erect a hybrid deployed/assembled structure as an early space experiment in large space structures technology. The basic objectives can be broken down into three generic areas: (1) by performing assembly tasks both in space and in neutral buoyancy simulation, a mathematical basis will be found for the validity conditions of neutral buoyancy, thus enhancing the utility of water as a medium for simulation of weightlessness; (2) a data base will be established describing the capabilities and limitations of EVA crewmembers, including effects of such things as hardware size and crew restraints; and (3) experience of the M.I.T. Space Systems Lab in neutral buoyancy simulation of large space structures assembly indicates that the assembly procedure may create the largest loads that a structure will experience during its lifetime. Data obtained from the experiment will help establish an accurate loading model to aid designers of future space structures.

  6. Effect of spaceflight on the isotonic contractile properties of single skeletal muscle fibers in the rhesus monkey

    Science.gov (United States)

    Fitts, R. H.; Romatowski, J. G.; Blaser, C.; De La Cruz, L.; Gettelman, G. J.; Widrick, J. J.

    2000-01-01

    Experiments from both Cosmos and Space Shuttle missions have shown weightlessness to result in a rapid decline in the mass and force of rat hindlimb extensor muscles. Additionally, despite an increased maximal shortening velocity, peak power was reduced in rat soleus muscle post-flight. In humans, declines in voluntary peak isometric ankle extensor torque ranging from 15-40% have been reported following long- and short-term spaceflight and prolonged bed rest. Complete understanding of the cellular events responsible for the fiber atrophy and the decline in force, as well as the development of effective countermeasures, will require detailed knowledge of how the physiological and biochemical processes of muscle function are altered by spaceflight. The specific purpose of this investigation was to determine the extent to which the isotonic contractile properties of the slow- and fast-twitch fiber types of the soleus and gastrocnemius muscles of rhesus monkeys (Macaca mulatta) were altered by a 14-day spaceflight.

  7. Measurement of Acute Changes in Choroid Thickness in Healthy Eyes During Posture Change Using Optical Coherence Tomography

    Science.gov (United States)

    Ferguson, Connor R.; Lee, Stuart M. C.; Stenger, Michael B.; Laurie, Steven S.

    2015-01-01

    The Visual Impairment and Intracranial Pressure (VIIP) syndrome affects 60% of astronauts returning from long-duration missions and is characterized by structural and functional changes of the eye (3). Upon entry into weightlessness, approximately two liters of fluid translocates from the lower body to the thorax and cephalad regions, potentially contributing to elevated intracranial and intraocular pressures. The choroid is the vasculature that supplies blood flow to the posterior part of the retina and has limited autoregulation. As a consequence these vessels may engorge during a cephalad fluid shift, contributing to structural changes in the retina. The purpose of this experiment was to quantify changes in choroid thickness during a fluid shift. In order to fulfill this objective, it was also necessary to improve the measurement technique for assessing choroid thickness.

  8. View of human problems to be addressed for long-duration space flights

    Science.gov (United States)

    Berry, C. A.

    1973-01-01

    Review of the principal physiological changes seen in space flight, and discussion of various countermeasures which may prove to be useful in combating these changes in long-term space flight. A number of transient changes seen in Apollo astronauts following space flights are discussed, including cardiovascular and hemodynamic responses to weightlessness, musculoskeletal changes, changes in fluid and electrolyte balance, microbiological changes, and vestibular effects. A number of countermeasures to the effects of space flight on man are cited, including exercise, medication, diet, lower-body negative pressure, gradient positive pressure, venous occlusion cuffs, and others. A detailed review is then made of a number of psychological factors bearing on the ability of the human organism to withstand the rigors of long space flights.

  9. Effect of antigravity suit inflation on cardiovascular, PRA, and PVP responses in humans. [Plasma Renin Activity and Plasma VasoPressin

    Science.gov (United States)

    Kravik, S. E.; Keil, L. C.; Geelen, G.; Wade, C. E.; Barnes, P. R.

    1986-01-01

    The effects of lower body and abdominal pressure, produced by antigravity suit inflation, on blood pressure, pulse rate, fluid and electrolyte shift, plasma vasopressin and plasma renin activity in humans in upright postures were studied. Five men and two women stood upright for 3 hr with the suit being either inflated or uninflated. In the control tests, the suit was inflated only during the latter part of the trials. Monitoring was carried out with a sphygnomanometer, with sensors for pulse rates, and using a photometer and osmometer to measure blood serum characteristics. The tests confirmed earlier findings that the anti-g suit eliminates increases in plasma renin activity. Also, the headward redistribution of blood obtained in the tests commends the anti-g suit as an alternative to water immersion or bed rest for initial weightlessness studies.

  10. High-density support matrices: Key to the deep borehole disposal of spent nuclear fuel

    Energy Technology Data Exchange (ETDEWEB)

    Gibb, F.G.F. [Immobilisation Science Laboratory, Department of Engineering Materials, University of Sheffield, Sheffield S1 3JD (United Kingdom)], E-mail: f.gibb@sheffield.ac.uk; McTaggart, N.A.; Travis, K.P.; Burley, D. [Immobilisation Science Laboratory, Department of Engineering Materials, University of Sheffield, Sheffield S1 3JD (United Kingdom); Hesketh, K.W. [Nexia Solutions Ltd., B709 Springfields, Preston PR4 0XJ (United Kingdom)

    2008-03-15

    Deep (4-5 km) boreholes are emerging as a safe, secure, environmentally sound and potentially cost-effective option for disposal of high-level radioactive wastes, including plutonium. One reason this option has not been widely accepted for spent fuel is because stacking the containers in a borehole could create load stresses threatening their integrity with potential for releasing highly mobile radionuclides like {sup 129}I before the borehole is filled and sealed. This problem can be overcome by using novel high-density support matrices deployed as fine metal shot along with the containers. Temperature distributions in and around the disposal are modelled to show how decay heat from the fuel can melt the shot within weeks of disposal to give a dense liquid in which the containers are almost weightless. Finally, within a few decades, this liquid will cool and solidify, entombing the waste containers in a base metal sarcophagus sealed into the host rock.

  11. Altered carbohydrate, lipid, and xenobiotic metabolism by liver from rats flown on Cosmos 1887

    Science.gov (United States)

    Merrill, A. H. Jr; Hoel, M.; Wang, E.; Mullins, R. E.; Hargrove, J. L.; Jones, D. P.; Popova, I. A.; Merrill AH, J. r. (Principal Investigator)

    1990-01-01

    To determine the possible biochemical effects of prolonged weightlessness on liver function, samples of liver from rats that had flown aboard Cosmos 1887 were analyzed for protein, glycogen, and lipids as well as the activities of a number of key enzymes involved in metabolism of these compounds and xenobiotics. Among the parameters measured, the major differences were elevations in the glycogen content and hydroxymethylglutaryl-CoA (HMG-CoA) reductase activities for the rats flown on Cosmos 1887 and decreases in the amount of microsomal cytochrome P-450 and the activities of aniline hydroxylase and ethylmorphine N-demethylase, cytochrome P-450-dependent enzymes. These results support the earlier finding of differences in these parameters and suggest that altered hepatic function could be important during spaceflight and/or the postflight recovery period.

  12. Cardiovascular regulatory response to lower body negative pressure following blood volume loss

    Science.gov (United States)

    Shimizu, M.; Ghista, D. N.; Sandler, H.

    1979-01-01

    An attempt is made to explain the cardiovascular regulatory responses to lower body negative pressure (LBNP) stress, both in the absence of and following blood or plasma volume loss, the latter being factors regularly observed with short- or long-term recumbency or weightlessness and associated with resulting cardiovascular deconditioning. Analytical expressions are derived for the responses of mean venous pressure and blood volume pooled in the lower body due to LBNP. An analysis is presented for determining the HR change due to LBNP stress following blood volume loss. It is concluded that the reduced orthostatic tolerance following long-term space flight or recumbency can be mainly attributed to blood volume loss, and that the associated cardiovascular responses characterizing this orthostatic intolerance is elicited by the associated central venous pressure response.

  13. U.S. biological experiments in space

    Science.gov (United States)

    Klein, H. P.

    1981-01-01

    The history of biologic experimentation in space is traced. Early balloon and rocket borne animals showed no abnormalities on the macroscale, and biosatellite launches with bacteria and amoebae revealed no microscopic dysfunctions. Adult Drosophila flies on board Cosmos spacecraft died with a shortened lifespan, while their offspring lived full lifespans. Green pepper plants grown in weightlessness showed a different orientation, but no physiological disturbances. Normal bone growth in rats has been found to almost cease after 11 days in space, and the mean life span of red blood cells decreases by four days. A series of experiments designed by U.S. scientists will be performed on primates provided and flown by the U.S.S.R. Finally, experiments on board Spacelab will involve determination of the persistence of circadian rhythms in bacteria and humans.

  14. Effects of spaceflight on hypothalamic peptide systems controlling pituitary growth hormone dynamics

    Science.gov (United States)

    Sawchenko, P. E.; Arias, C.; Krasnov, I.; Grindeland, R. E.; Vale, W.

    1992-01-01

    Possible effects of reduced gravity on central hypophysiotropic systems controlling growth hormone (GH) secretion were investigated in rats flown on Cosmos 1887 and 2044 biosatellites. Immunohistochemical (IHC)staining for the growth hormone-releasing factor (GRF), somatostatin (SS), and other hypothalamic hormones was performed on hypothalami obtained from rats. IHC analysis was complemented by quantitative in situ assessments of mRNAs encoding the precursors for these hormones. Data obtained suggest that exposure to microgravity causes a preferential reduction in GRF peptide and mRNA levels in hypophysiotropic neurons, which may contribute to impared GH secretion in animals subjected to spaceflight. Effects of weightlessness are not mimicked by hindlimb suspension in this system.

  15. Surgical bleeding in microgravity

    Science.gov (United States)

    Campbell, M. R.; Billica, R. D.; Johnston, S. L. 3rd

    1993-01-01

    A surgical procedure performed during space flight would occur in a unique microgravity environment. Several experiments performed during weightlessness in parabolic flight were reviewed to ascertain the behavior of surgical bleeding in microgravity. Simulations of bleeding using dyed fluid and citrated bovine blood, as well as actual arterial and venous bleeding in rabbits, were examined. The high surface tension property of blood promotes the formation of large fluid domes, which have a tendency to adhere to the wound. The use of sponges and suction will be adequate to prevent cabin atmosphere contamination with all bleeding, with the exception of temporary arterial droplet streams. The control of the bleeding with standard surgical techniques should not be difficult.

  16. Metabolic changes observed in astronauts

    Science.gov (United States)

    Leach, Carolyn S.; Cintron, N. M.; Krauhs, J. M.

    1991-01-01

    Results of medical experiments with astronauts reveal rapid loss of volume (2 l) from the legs and a transient early increase in left ventricular volume index. These findings indicate that, during space flight, fluid is redistributed from the legs toward the head. In about 2 days, total body water decreases 2 to 3 percent. Increased levels of plasma renin activity and antidiuretic hormone while blood sodium and plasma volume are reduced suggest that space flight-associated factors are influencing the regulatory systems. In addition to fluid and electrolyte loss, Skylab astronauts lost an estimated 0.3 kg of protein. Endocrine factors, including increased cortisol and thyroxine and decreased insulin, are favorable for protein catabolism. The body appears to adapt to weightlessness at some physiologic cost. Readaptation to earth's gravity at landing becomes another physiologic challenge.

  17. Gravity Plant Physiology Facility (GPPF) Team in the Spacelab Payload Operations Control Center (SL

    Science.gov (United States)

    1992-01-01

    The primary payload for Space Shuttle Mission STS-42, launched January 22, 1992, was the International Microgravity Laboratory-1 (IML-1), a pressurized manned Spacelab module. The goal of IML-1 was to explore in depth the complex effects of weightlessness of living organisms and materials processing. Around-the-clock research was performed on the human nervous system's adaptation to low gravity and effects of microgravity on other life forms such as shrimp eggs, lentil seedlings, fruit fly eggs, and bacteria. Materials processing experiments were also conducted, including crystal growth from a variety of substances such as enzymes, mercury iodide, and a virus. The Huntsville Operations Support Center (HOSC) Spacelab Payload Operations Control Center (SL POCC) at the Marshall Space Flight Center (MSFC) was the air/ground communication channel used between the astronauts and ground control teams during the Spacelab missions. Featured is the Gravity Plant Physiology Facility (GPPF) team in the SL POCC during the IML-1 mission.

  18. The Drop Tower Bremen -An Overview

    Science.gov (United States)

    von Kampen, Peter; Könemann, Thorben; Rath, Hans J.

    The Center of Applied Space Technology and Microgravity (ZARM) was founded in 1985 as an institute of the University of Bremen, which focuses on research on gravitational and space-related phenomena. In 1988, the construction of ZARM`s drop tower began. Since its inau-guration in September 1990, the eye-catching Drop Tower Bremen with a height of 146m and its characteristic glass roof has become twice a landmark on the campus of the University of Bremen and the emblem of the technology park Bremen. As such an outstanding symbol of space science in Bremen the drop tower provides an european unique facility for experiments under conditions of high-quality weightlessness with residual gravitational accelerations in the microgravity regime. The period of maximum 4.74s of each freely falling experiment at the Drop Tower Bremen is only limited by the height of the drop tower vacuum tube, which was fully manufactured of steal and enclosed by an outer concrete shell. Thus, the pure free fall height of each microgravity drop experiment is approximately 110m. By using the later in-stalled catapult system established in 2004 ZARM`s short-term microgravity laboratory is able to nearly double the time of free fall. This world-wide inimitable capsule catapult system meets scientists` demand of extending the period of weightlessness. During the catapult operation the experiment capsule performs a vertical parabolic flight within the drop tower vacuum tube. In this way the time of microgravity can be extended to slightly over 9s. Either in the drop or in the catapult operation routine the repetition rates of microgravity experiments at ZARM`s drop tower facility are the same, generally up to 3 times per day. In comparison to orbital platforms the ground-based laboratory Drop Tower Bremen represents an economic alternative with a permanent access to weightlessness on earth. Moreover, the exceptional high quality of weightlessness in order of 1e-6 g (in the frequency range below 100

  19. Microgravity research in plant biological systems: Realizing the potential of molecular biology

    Science.gov (United States)

    Lewis, Norman G.; Ryan, Clarence A.

    1993-01-01

    The sole all-pervasive feature of the environment that has helped shape, through evolution, all life on Earth is gravity. The near weightlessness of the Space Station Freedom space environment allows gravitational effects to be essentially uncoupled, thus providing an unprecedented opportunity to manipulate, systematically dissect, study, and exploit the role of gravity in the growth and development of all life forms. New and exciting opportunities are now available to utilize molecular biological and biochemical approaches to study the effects of microgravity on living organisms. By careful experimentation, we can determine how gravity perception occurs, how the resulting signals are produced and transduced, and how or if tissue-specific differences in gene expression occur. Microgravity research can provide unique new approaches to further our basic understanding of development and metabolic processes of cells and organisms, and to further the application of this new knowledge for the betterment of humankind.

  20. Behaviour of Human Hemodynamics under Microcavity –a Proposal for the 7th German Parabolic Flight Campaign

    Directory of Open Access Journals (Sweden)

    Vladimir Blazek

    2005-01-01

    Full Text Available All astronauts often feel uncomfortable during first encounter microgravity because of fluid shifts from the lower extremities to the head caused by weightlessness. Parabolic flights offer a great possibility for research of this phenomenon under “zero gravity”. With a combination of the optoelectronic sensor concepts PPG and PPGI and an ultrasound device it should be possible to measure all relevant parameters for description and further explanation of rapid fluid shifts along the body axis in humans during parabolic flights. A research team of the RWTH Aachen University and the Charité University Berlin will participate in the 7th German Parabolic Flight Campaign in September 2005 and perform the experiments under micro gravitation. A combination of used non-invasive strategies will reveal new insights into the human hemodynamics under microgravity conditions. The optoelectronic part of this interdisciplinary research experiment, details from the measuring setup, data collecting and post processing will be discussed.

  1. Heat transfers and related effects in supercritical fluids

    CERN Document Server

    Zappoli, Bernard; Garrabos, Yves

    2015-01-01

    This book investigates the unique hydrodynamics and heat transfer problems that are encountered in the vicinity of the critical point of fluids. Emphasis is given on weightlessness conditions, gravity effects and thermovibrational phenomena. Near their critical point, fluids indeed obey universal behavior and become very compressible and expandable. Their comportment, when gravity effects are suppressed, becomes quite unusual. The problems that are treated in this book are of interest to students and researchers interested in the original behavior of near-critical fluids as well as to engineers that have to manage supercritical fluids. A special chapter is dedicated to the present knowledge of critical point phenomena. Specific data for many fluids are provided, ranging from cryogenics (hydrogen) to high temperature (water). Basic information in statistical mechanics, mathematics and measurement techniques is also included. The basic concepts of fluid mechanics are given for the non-specialists to be able to ...

  2. Critical Point Facility (CPE) Group in the Spacelab Payload Operations Control Center (SL POCC)

    Science.gov (United States)

    1992-01-01

    The primary payload for Space Shuttle Mission STS-42, launched January 22, 1992, was the International Microgravity Laboratory-1 (IML-1), a pressurized manned Spacelab module. The goal of IML-1 was to explore in depth the complex effects of weightlessness of living organisms and materials processing. Around-the-clock research was performed on the human nervous system's adaptation to low gravity and effects of microgravity on other life forms such as shrimp eggs, lentil seedlings, fruit fly eggs, and bacteria. Materials processing experiments were also conducted, including crystal growth from a variety of substances such as enzymes, mercury iodide, and a virus. The Huntsville Operations Support Center (HOSC) Spacelab Payload Operations Control Center (SL POCC) at the Marshall Space Flight Center (MSFC) was the air/ground communication channel used between the astronauts and ground control teams during the Spacelab missions. Featured is the Critical Point Facility (CPE) group in the SL POCC during STS-42, IML-1 mission.

  3. Mechanisms of Orthostatic Intolerance During Real and Simulated Microgravity

    Science.gov (United States)

    1997-01-01

    Session MP1 includes short reports on: (1) Orthostatic Tests after 42 Days of Simulated Weightlessness; (2) Effects of 12 Days Exposure to Simulated Microgravity on Central Circulatory Hemodynamics in the Rhesus Monkey; (3) Increased Sensitivity and Resetting of Baroflex Control of Exercise Heart Rate After Prolonged Bed-Rest; (4) Complex Cardiovascular Dynamics and Deconditioning During Head-down Bed Rest; (5) The Cardiovascular Effects of 6 Hours of Head-down Tilt Upon Athletes and Non-athletes; (6) Individual Susceptibility to Post-spaceflight Orthostatic Intolerance: Contributions of Gender-related and Microgravity-related Factors; (7) Cassiopee Mission 1996: Comparison of Cardiovascular Alteration after Short and Long-term Spaceflights; (8) Cerebral and Femoral Flow Response to LBNP during 6 Month MIR Spaceflights (93-95); and (9) Cerebrovascular Changes due to Spaceflight and Postflight Presyncope.

  4. Investigations on-board the biosatellite Cosmos-83

    Science.gov (United States)

    Gazenko, O. G.; Ilyin, Eu. A.

    The program of the 5day flight of the biosatellite Cosmos-1514 (December 1983) envisaged experimental investigations the purpose of which was to ascertain the effect of short-term microgravity on the physiology, growth and development of various animal and plant species. The study of Rhesus-monkeys has shown that they are an adequate model for exploring the mechanisms of physiological adaptation to weightlessness of the vestibular apparatus and the cardiovascular system. The rat experiment has demonstrated that mammalian embryos, at least during the last term of pregnancy, can develop in microgravity. This finding has been confirmed by fish studies. The experiment on germinating seeds and adult plants has given evidence that microgravity produces no effect on the metabolism of seedlings and on the flowering stage.

  5. Life sciences and space research XXI(2); Proceedings of the Seventh and Eleventh Workshops, Graz, Austria, June 25-July 7, 1984

    Science.gov (United States)

    Oser, H. (Editor); Oro, J. (Editor); Macelroy, R. D. (Editor); Klein, H. P. (Editor); Devincenzi, D. L. (Editor); Young, R. S. (Editor)

    1984-01-01

    Space-based and space-related research in the life sciences is presented in reviews and reports. Topics examined include the long-term effects of weightlessness, cosmic chemistry and chemical and biological evolution, life-support systems for space travel, planetary protection, and the g-scale factor in gravitational biology. Consideration is given to the role of Ca ions in cytological effects of hypogravity, the organic aerosols of Titan, the role of meteorite impacts in the formation of organic molecules, prebiotic synthesis of purines and pyrimidines, atmosphere behavior of gas-closed mouse-algal systems, air and water regeneration in advanced regenerative environmental-control and life-support systems, and the influence of gravity on the development of animal systems.

  6. STS-40 crew trains in JSC's SLS mockup located in Bldg 36

    Science.gov (United States)

    1987-01-01

    STS-40 Payload Specialist Millie Hughes-Fulford along with backup payload specialist Robert Ward Phillips familiarize themselves with Spacelab Life Sciences 1 (SLS-1) equipment. The two scientists are in JSC's Life Sciences Project Division (LSPD) SLS mockup located in the Bioengineering and Test Support Facility Bldg 36. Hughes-Fulford, in the center aisle, pulls equipment from an overhead stowage locker while Phillips, in the foreground, experiments with the baroreflex neck pressure chamber at Rack 11. The baroreflex collar will be used in conjuction with Experiment No. 022, Influence of Weightlessness Upon Human Autonomic Cardiovascular Control. Behind Phillips in the center aisle are body mass measurement device (BMMD) (foreground) and the stowed bicycle ergometer.

  7. Preliminary results of scientific research on biosatellite Kosmos-1129

    Science.gov (United States)

    1980-01-01

    The first physiological study aimed at deeper examination mechanisms of weightlessness and adaptation/readaptation is described. It dealt with metabolism, support motor changes and nonspecific changes connected with stress reaction. Wistar rats were used in a triple setup: flight/vivarium/biosatellite mockup. Animal condition was assessed on motor activity and body temperature. Extensive tables show weight, blood and enzyme analysis, etc. Animals groups were labeled: stress, behavior, body composition, biorhythm, ontogenesis. The second or biological study dealt with tumorous carrot tissues but humidity control was defective: some indices are reported such as cell membrane permeability, tissue respiration, etc. It also was concerned with a fowl embryogenetic experiment (Japanese quail) but mechanical effects on landing reduced its success. The third study, on radiation dosimetry, presents a little tabulated data but chiefly gives lists of satellite detector units of different kinds and from different countries.

  8. [Histomorphometric analysis of the bones of rats on board the Kosmos 1667 biosatellite].

    Science.gov (United States)

    Kaplanskiĭ, A S; Durnova, G N; Sakharova, Z F; Il'ina-Kakueva, E I

    1987-01-01

    Bones of the rats flown on Cosmos-1667 were examined histologically and histomorphometrically. It was found that 7-day exposure to weightlessness led to osteoporosis in the spongy matter of proximal metaphyses of tibia and, although to a lesser extent, in the spongiosa of lumbar vertebrae whereas no signs of osteoporosis were seen in the spongy matter of iliac bones. Osteoporosis in the spongy matter of the above bones developed largely due to the inhibition of bone neoformation, which was indicated by a decrease in the number and activity of osteoblasts. Increased bone resorption (as shown by a greater number and activity of osteoclasts) was observed only in the spongy matter of tibial metaphyses. It is emphasized that a reduction of the number of highly active osteoblasts in spongy bones is one of the early signs of inhibition of bone neoformation and development of osteoporosis.

  9. Liquid-bridge breakup in contact-drop dispensing: Liquid-bridge stability with a free contact line.

    Science.gov (United States)

    Akbari, Amir; Hill, Reghan J; van de Ven, Theo G M

    2015-08-01

    The static stability of weightless liquid bridges with a free contact line with respect to axisymmetric and nonaxisymmetric perturbations is studied. Constant-volume and constant-pressure stability regions are constructed in slenderness versus cylindrical volume diagrams for fixed contact angles. Bifurcations along the stability-region boundaries are characterized by the structure of axisymmetric bridge branches and families of equilibria. A wave-number definition is presented based on the pieces-of-sphere states at branch terminal points to classify equilibrium branches and identify branch connections. Compared with liquid bridges pinned at two equal disks, the free contact line breaks the equatorial and reflective symmetries, affecting the lower boundary of the constant-volume stability region where axisymmetric perturbations are critical. Stability is lost at transcritical bifurcations and turning points along this boundary. Our results furnish the maximum-slenderness stability limit for drop deposition on real surfaces when the contact angle approaches the receding contact angle.

  10. Gas spreading on a heated wall wetted by liquid

    CERN Document Server

    Garrabos, Y; Hegseth, J; Nikolayev, Vadim; Beysens, D; Delville, J -P

    2016-01-01

    This study deals with a simple pure fluid whose temperature is slightly below its critical temperature and whose density is nearly critical, so that the gas and liquid phases coexist. Under equilibrium conditions, such a liquid completely wets the container wall and the gas phase is always separated from the solid by a wetting film. We report a striking change in the shape of the gas-liquid interface influenced by heating under weightlessness where the gas phase spreads over a hot solid surface showing an apparent contact angle larger than 90{\\textdegree}. We show that the two-phase fluid is very sensitive to the differential vapor recoil force and give an explanation that uses this nonequilibrium effect. We also show how these experiments help to understand the boiling crisis, an important technological problem in high-power boiling heat exchange.

  11. The development of the hardware for studying biological clock systems under microgravity conditions, using scorpions as animal models

    Science.gov (United States)

    Serafini, L.; Viganò, W.; Donati, A.; Porciani, M.; Zolesi, V.; Schulze-Varnholt, D.; Manieri, P.; El-Din Sallam, A.; Schmäh, M.; Horn, E. R.

    2007-02-01

    The study of internal clock systems of scorpions in weightless conditions is the goal of the SCORPI experiment. SCORPI was selected for flight on the International Space Station (ISS) and will be mounted in the European facility BIOLAB, the European Space Agency (ESA) laboratory designed to support biological experiments on micro-organisms, cells, tissue, cultures, small plants and small invertebrates. This paper outlines the main features of a breadboard designed and developed in order to allow the analysis of critical aspects of the experiment. It is a complete tool to simulate the experiment mission on ground and it can be customised, adapted and tuned to the scientific requirements. The paper introduces the SCORPI-T experiment which represents an important precursor for the success of the SCORPI on BIOLAB. The capabilities of the hardware developed show its potential use for future similar experiments in space.

  12. Leidenfrost droplets in an electric field

    Science.gov (United States)

    Wildeman, Sander; Sun, Chao; Lohse, Detlef

    2014-11-01

    In a recent video broadcast dubbed the ``Knitting Needle Experiment,'' astronaut Don Petit aboard the ISS demonstrated how weightless water droplets can be made to orbit a statically charged Teflon rod. We study the earthly analogue of mobile droplets in an electric field, whereby the mobility is ensured by a thin vapor film sustained between the droplet and a hot plate (the Leidenfrost effect). We find that in a strong vertical electric field the droplet starts to bounce progressively higher, defying gravitational attraction. From its trajectory we can deduce the temporal evolution of the charge on the droplet. The measurements show that the charge starts high and then decreases in a step-like manner as the droplet evaporates. The discharge trend is predicted well by treating the droplet as a dielectric sphere in electrical contact with the hot plate, but the mechanism by which definite lumps of charge are transferred through the vapor film is still an open question.

  13. Development of limb volume measuring system

    Science.gov (United States)

    Bhagat, P. K.; Kadaba, P. K.

    1983-01-01

    The mechanisms underlying the reductions in orthostatic tolerance associated with weightlessness are not well established. Contradictory results from measurements of leg volume changes suggest that altered venomotor tone and reduced blood flow may not be the only contributors to orthostatic intolerance. It is felt that a more accurate limb volume system which is insensitive to environmental factors will aid in better quantification of the hemodynamics of the leg. Of the varous limb volume techniques presently available, the ultrasonic limb volume system has proven to be the best choice. The system as described herein is free from environmental effects, safe, simple to operate and causes negligible radio frequency interference problems. The segmental ultrasonic ultrasonic plethysmograph is expected to provide a better measurement of limb volume change since it is based on cross-sectional area measurements.

  14. Current Concepts and Future Directions of CELSS

    Science.gov (United States)

    Macelroy, R. D.; Bredt, J.

    1985-01-01

    Bioregenerative life support systems for use in space were studied. Concepts of such systems include the use of higher plants and/or microalgae as sources of food, potable water and oxygen, and as sinks for carbon dioxide and metabolic wastes. Recycling of materials within the system will require processing of food organism and crew wastes using microbiological and/or physical chemical techniques. The dynamics of material flow within the system will require monitoring, control, stabilization and maintenance imposed by computers. Studies included higher plant and algal physiology, environmental responses, and control; flight experiments for testing responses of organisms to weightlessness and increased radiation levels; and development of ground based facilities for the study of recycling within a bioregenerative life support system.

  15. Evidence that Resorption of Bone by Rat Peritoneal Macrophages Occurs in an Acidic Environment

    Science.gov (United States)

    Blair, H. C.

    1985-01-01

    Skeletal loss in space, like any form of osteoporosis, reflects a relative imbalance of the activities of cells resorbing (degrading) or forming bone. Consequently, prevention of weightlessness induced bone loss may theoretically be accomplished by (1) stimulating bone formation or (2) inhibiting bone resorption. This approach, however, requires fundamental understanding of the mechanisms by which cells form or degrade bone, information not yet at hand. An issue central to bone resorption is the pH at which resorption takes place. The pH dependent spectral shift of a fluorescent dye (fluorescein isothiocyanate) conjugated to bone matrix was used to determine the pH at the resorptive cell bone matrix interface. Devitalized rat bone was used as the substrate, and rat peritoneal macrophages were used as the bone resorbing cells. The results suggest that bone resorption is the result of generation of an acidic microenvironment at the cell matrix junction.

  16. The calcium endocrine system of adolescent rhesus monkeys and controls before and after spaceflight

    Science.gov (United States)

    Arnaud, Sara B.; Navidi, Meena; Deftos, Leonard; Thierry-Palmer, Myrtle; Dotsenko, Rita; Bigbee, Allison; Grindeland, Richard E.

    2002-01-01

    The calcium endocrine system of nonhuman primates can be influenced by chairing for safety and the weightless environment of spaceflight. The serum of two rhesus monkeys flown on the Bion 11 mission was assayed pre- and postflight for vitamin D metabolites, parathyroid hormone, calcitonin, parameters of calcium homeostasis, cortisol, and indexes of renal function. Results were compared with the same measures from five monkeys before and after chairing for a flight simulation study. Concentrations of 1,25-dihydroxyvitamin D were 72% lower after the flight than before, and more than after chairing on the ground (57%, P endocrine system were similar to the effects of chairing on the ground, but were more pronounced. Reduced intestinal calcium absorption, losses in body weight, increases in cortisol, and higher postflight blood urea nitrogen were the changes in flight monkeys that distinguished them from the flight simulation study animals.

  17. Do the design concepts used for the space flight hardware directly affect cell structure and/or cell function ground based simulations

    Science.gov (United States)

    Chapman, David K.

    1989-01-01

    The use of clinostats and centrifuges to explore the hypogravity range between zero and 1 g is described. Different types of clinostat configurations and clinostat-centrifuge combinations are compared. Some examples selected from the literature and current research in gravitational physiology are presented to show plant responses in the simulated hypogravity region of the g-parameter (0 is greater than g is greater than 1). The validation of clinostat simulation is discussed. Examples in which flight data can be compared to clinostat data are presented. The data from 3 different laboratories using 3 different plant species indicate that clinostat simulation in some cases were qualitatively similar to flight data, but that in all cases were quantitatively different. The need to conduct additional tests in weightlessness is emphasized.

  18. A compact equipment package for vestibular experiments during spaceflight

    Science.gov (United States)

    Clarke, A. H.; Teiwes, W.; Scherer, H.

    A compact measurement and stimulus equipment package for vestibular testing is described. The package is designed on a modular concept so that a customized version can be assembled for each experimental situation. Although primarily conceived for space-related research, the equipment has also been introduced successfully into the clinical diagnostic procedure. An essential function of the equipment is the recording and evaluation of eye movements. This is performed by a video-based measurement system which permits evaluation of horizontal, vertical and torsional components of eye movement. Objective testing of the vestibulo-ocular reflex in all three orthogonal planes is therefore possible. Furthermore evaluation of the otolithic function in weightlessness is made feasible by the possibility of measuring dynamic ocular counterrolling. Some applications of the equipment are described.

  19. Hindlimb suspension and SPE-like radiation impairs clearance of bacterial infections.

    Directory of Open Access Journals (Sweden)

    Minghong Li

    Full Text Available A major risk of extended space travel is the combined effects of weightlessness and radiation exposure on the immune system. In this study, we used the hindlimb suspension model of microgravity that includes the other space stressors, situational and confinement stress and alterations in food intake, and solar particle event (SPE-like radiation to measure the combined effects on the ability to control bacterial infections. A massive increase in morbidity and decrease in the ability to control bacterial growth was observed using 2 different types of bacteria delivered by systemic and pulmonary routes in 3 different strains of mice. These data suggest that an astronaut exposed to a strong SPE during extended space travel is at increased risk for the development of infections that could potentially be severe and interfere with mission success and astronaut health.

  20. The Franco-American macaque experiment. [bone demineralization of monkeys on Space Shuttle

    Science.gov (United States)

    Cipriano, Leonard F.; Ballard, Rodney W.

    1988-01-01

    The details of studies to be carried out jointly by French and American teams on two rhesus monkeys prepared for future experiments aboard the Space Shuttle are discussed together with the equipment involved. Seven science discipline teams were formed, which will study the effects of flight and/or weightlessness on the bone and calcium metabolism, the behavior, the cardiovascular system, the fluid balance and electrolytes, the muscle system, the neurovestibular interactions, and the sleep/biorhythm cycles. New behavioral training techniques were developed, in which the animals were trained to respond to behavioral tasks in order to measure the parameters involving eye/hand coordination, the response time to target tracking, visual discrimination, and muscle forces used by the animals. A large data set will be obtained from different animals on the two to three Space Shuttle flights; the hardware technologies developed for these experiments will be applied for primate experiments on the Space Station.

  1. Development of tissue culture techniques and hardware to study mineralization under microgravity conditions

    Science.gov (United States)

    van Loon, J. J. W. A.; Veldhuijzen, J. P.; Windgassen, E. J.; Brouwer, T.; Wattel, K.; van Vilsteren, M.; Maas, P.

    1994-08-01

    To study the effects of weightlessness on mouse fetal long bone rudiment growth and mineralization we have developed a tissue culture system for the Biorack facility of Spacelab. The technique uses standard liquid tissue culture medium, supplemented with Na-β-glycerophosphate, confined in gas permeable polyethylene bags mounted inside ESA Biorack Type I experiment containers. The containers can be flushed with an air/5% CO2 gas mixture necessary for the physiological bicarbonate buffer used. Small amounts of fluid can be introduced at the beginning (e.g. radioactive labels for incorporation studies) or at the end of the experiment (fixatives). A certain form of mechanical stimulation (continuous compression) can be used to counteract the, possibly, adverse effect of μ-gravity. Using 16 day old metatarsals the in vitro calcification process under μ-gravity conditions can be studied for a 4 day period.

  2. Bioassay of body fluids, experiment M005

    Science.gov (United States)

    Dietlein, L. F.; Harris, E. S.

    1971-01-01

    Preflight and postflight urine and plasma samples from the Gemini 7 and Gemini 9 crewmembers were analyzed. Electrolyte and water retention observed immediately postflight was consistent with the assumption that the Gauer-Henry atrial reflex was responsive to a change from the weightless to the unit-gravity environment. Immediately postflight, plasma 17-hydroxycorticosteroid concentrations were increased and plasma uric acid concentration was decreased. The increased excretion of 17-hydroxycorticosteroids immediately postflight probably was caused by the stress of entry. The postflight increase of plasma protein, and the slightly smaller increase of plasma electrolytes postflight, was consistent with an inflight water and electrolyte loss that resulted in postflight retention of water and electrolytes.

  3. Vectorcardiographic changes during extended space flight (M093): Observations at rest and during exercise

    Science.gov (United States)

    Smith, R. F.; Stanton, K.; Stoop, D.; Brown, D.; Janusz, W.; King, P.

    1977-01-01

    The objectives of Skylab Experiment M093 were to measure electrocardiographic signals during space flight, to elucidate the electrophysiological basis for the changes observed, and to assess the effect of the change on the human cardiovascular system. Vectorcardiographic methods were used to quantitate changes, standardize data collection, and to facilitate reduction and statistical analysis of data. Since the Skylab missions provided a unique opportunity to study the effects of prolonged weightlessness on human subjects, an effort was made to construct a data base that contained measurements taken with precision and in adequate number to enable conclusions to be made with a high degree of confidence. Standardized exercise loads were incorporated into the experiment protocol to increase the sensitivity of the electrocardiogram for effects of deconditioning and to detect susceptability for arrhythmias.

  4. In vitro seed to seed growth on clinostats

    Science.gov (United States)

    Hoshizaki, T.

    1984-01-01

    The effect of a long term micro-gravity environment on the life cycle of plants is unknown. Whether higher plants have evolved to a stage where removal or reduction of gravity is detrimental to plant life cycle and thus fatal to the plant species, is an unanswered question in space plants which were successfully grown through the various stages of their life cycle. Attempts to grow plants as a continuous integral process from seed to seed through one generation were successful until recently. Culture of plants through multiple generations was not accomplished in space nor in ground based studies. The effect of long term simulated weightlessness by growing consecutive generations of plants continuously on clinostats using the cruciferous plants, Arabidopsis thaliana (L.) Heyn. and Cardamine oligosperma Nutt. is being investigated.

  5. Effect of cultural conditions on the seed-to-seed growth of Arabidopsis and Cardamine - A study of growth rates and reproductive development as affected by test tube seals

    Science.gov (United States)

    Hoshizaki, T.

    1982-01-01

    The effects of test tube seals on the growth, flowering, and seed pod formation of Arabidopsis thaliana (L.) Heynh., mouse ear cress, and Cardamine oligosperma Nutt, bitter cress, are studied in order to assess the conditions used in weightlessness experiments. Among other results, it is found that the growth (height) and flowering (date of bud appearance) were suppressed in mouse ear cress in tubes sealed with Saran. Seed pod formation which occurred by day 45 in open-to-air controls, was still lacking in the sealed plants even up to day 124. The growth and flowering of bitter cress were also suppressed by the Saran seal, although up to day 55 the Saran-sealed plants were taller. It is suggested that atmospheric composition was the cause of the suppression of growth, flowering, and seed pod development in these plants, since the mouse ear cress renewed their growth and then set seed pods after the Saran seal was ruptured.

  6. Ultrastructure of meristem and root cap of pea seedlings under spaceflight conditions

    Science.gov (United States)

    Sytnyk, K. M.; Kordyum, E. L.; Bilyavska, N. O.; Tarasenko, V. O.

    1983-01-01

    Data of electron microscopic analysis of meristem and root cap of pea seedlings grown aboard the Salyut-6 orbital research station in the Oazis apparatus and in the laboratory are presented. The main morphological and anatomical characteristics of the test and control plants are shown to be similar. At the same time, some differences are found in the structural and functional organization of the experimental cells as compared to the controls. They concern first of all the plastic apparatus, mitochondria and Golgi apparatus. It is assumed that cell function for certain periods of weightlessness on the whole ensures execution of the cytodifferentiation programs genetically determined on the Earth. Biochemical and physiological processes vary rather markedly due to lack of initially rigorous determination.

  7. The CFVib Experiment: Control of Fluids in Microgravity with Vibrations

    Science.gov (United States)

    Fernandez, J.; Sánchez, P. Salgado; Tinao, I.; Porter, J.; Ezquerro, J. M.

    2017-08-01

    The Control of Fluids in Microgravity with Vibrations (CFVib) experiment was selected for the 2016 Fly Your Thesis! programme as part of the 65th ESA Parabolic Flight Campaign. The aim of the project is to observe the potentially complex behaviour of vibrated liquids in weightless environments and to investigate the extent to which small-amplitude vibrations can be used to influence and control this behaviour. Piezoelectric materials are used to generate high-frequency vibrations to drive surface waves and large-scale reorientation of the interface. The theory of vibroequilibria, which treats the quasi-stationary surface configurations achieved by this reorientation, was used to predict interesting parameter regimes and interpret fluid behaviour. Here we describe the scientific motivation, objectives, and design of the experiment.

  8. The effect of artificial gravity on plasma and tissue lipids in rats: The Cosmos 936 experiment

    Science.gov (United States)

    Ahlers, I.; Praslička, M.; Tigranyan, R. A.

    Plasma and tissue lipids in male SPF Wistar rats flown for 18.5 days aboard the Cosmos 936 biosatellite were analyzed. One group of rats was subjected to artificial gravity by use of a centrifuge during the flight. An experiment simulating known space flight factors other than weightlessness was done on Earth. An increase of total cholesterol in plasma, of nonesterified fatty acids in plasma and brown adipose tissue, of triacylglycerols in plasma, liver, thymus and bone marrow was noted several hours after biosatellite landing. Smaller changes were observed in the terrestrial control experiment. With the exception of triacylglycerol accumulation in bone marrow, these increases disappeared 25 days after biosatellite landing. Exposing the rats aboard the biosatellite to artificial gravity was beneficial in the sense that such exposure inhibited the phospholipid and triacylglycerol increase in plasma and inhibited the increase of triacylglycerol in liver and especially in bone marrow.

  9. Report of Amphibian Development Group

    Science.gov (United States)

    Malacinski, G.

    1985-01-01

    Amphibian and fish embryos are extremely well suited for studies on pattern specification, whereas other systems (e.g., avian or mammalian) might be just as well suited for studies on differentiation or growth. Those distinctions are important for at least two reasons: (1) More precise focus regarding underlying mechanisms is called for when those distinctions are made. That facilitates the formulation of specific models or hypotheses; and (2) stress effects (i.e., the effects of weightlessness on structures (e.g., bones) which normally bear a load) are distinguished as being indirect, in contrast to direct effects of microgravity, which would be expected to act on pattern specification. That is, direct gravity effects are distinguished from indirect stress effects.

  10. Anthropometric changes and fluid shifts

    Science.gov (United States)

    Thornton, W. E.; Hoffler, G. W.; Rummel, J. A.

    1977-01-01

    In an effort to obtain the most comprehensive and coherent picture of changes under weightlessness, a set of measurements on Skylab 2 was initiated and at every opportunity, additional studies were added. All pertinent information from ancillary sources were gleaned and collated. On Skylab 2, the initial anthropometric studies were scheduled in conjunction with muscle study. A single set of facial photographs was made in-flight. Additional measurements were made on Skylab 3, with photographs and truncal and limb girth measurements in-flight. Prior to Skylab 4, it was felt there was considerable evidence for large and rapid fluid shifts, so a series of in-flight volume and center of mass measurements and infrared photographs were scheduled to be conducted in the Skylab 4 mission. A number of changes were properly documented for the first time, most important of which were the fluid shifts. The following description of Skylab anthropometrics address work done on Skylab 4 primarily.

  11. First Middle East Aircraft Parabolic Flights for ISU Participant Experiments

    Science.gov (United States)

    Pletser, Vladimir; Frischauf, Norbert; Cohen, Dan; Foster, Matthew; Spannagel, Ruven; Szeszko, Adam; Laufer, Rene

    2017-06-01

    Aircraft parabolic flights are widely used throughout the world to create microgravity environment for scientific and technology research, experiment rehearsal for space missions, and for astronaut training before space flights. As part of the Space Studies Program 2016 of the International Space University summer session at the Technion - Israel Institute of Technology, Haifa, Israel, a series of aircraft parabolic flights were organized with a glider in support of departmental activities on `Artificial and Micro-gravity' within the Space Sciences Department. Five flights were organized with manoeuvres including several parabolas with 5 to 6 s of weightlessness, bank turns with acceleration up to 2 g and disorientation inducing manoeuvres. Four demonstration experiments and two experiments proposed by SSP16 participants were performed during the flights by on board operators. This paper reports on the microgravity experiments conducted during these parabolic flights, the first conducted in the Middle East for science and pedagogical experiments.

  12. Zero-G fluid mechanics in animal and man

    Science.gov (United States)

    Sandler, H.

    1986-01-01

    Significant cardiovascular change occurs with spaceflight. Loss of normal hydrostatic pressure gradients (head-to-foot), present while upright on earth, results in significant headward fluid shift of vascular and interstitial fluids. The resultant fluid change also shifts the hydrostatic indifference point for the circulation. The persistent distention of neck veins and change in upper body tissue compliance initiates steps to adapt to and compensate for the sensed excess fluid. These result in a loss of intravascular volume through neuro-humoral mechanisms and the presence of a smaller heart size, leading to a state where the subject has a reduced adaptive capacity to stress, particularly to fluid shifts to the lower body as occurs when once again returning to earth. This article reviews what is known about the weightlessness-induced headward fluid shift and its effects on cardiovascular function.

  13. Questões emergentes das actuais negociações entre as crenças da imagem analógica e da imagem digital

    Directory of Open Access Journals (Sweden)

    Victor Flores

    2004-01-01

    Full Text Available The space is seen today as one of the main forces for the political mobilization of civilizations. Its perception and fixation was most dependent upon the images and the ways of seeing which both captured and expanded it infinitely. The invention of photography brought the promisse of its delimitation but it also produced its refraction and “deisterritorializatio”. Following Michel Foucault’s, Edward T. Hall’s and Vilém Flusser’s conceptions and theories of space and experience, we will try to articulate the ways photographic technology had contributed to the conventions and perspectives of a subjective and apolitical space which opened the way to the reassurance of weightless and non-concrete virtual spaces that seem to characterize XXI century experience.

  14. U.S. biological experiments in space

    Science.gov (United States)

    Klein, H. P.

    1981-01-01

    The history of biologic experimentation in space is traced. Early balloon and rocket borne animals showed no abnormalities on the macroscale, and biosatellite launches with bacteria and amoebae revealed no microscopic dysfunctions. Adult Drosophila flies on board Cosmos spacecraft died with a shortened lifespan, while their offspring lived full lifespans. Green pepper plants grown in weightlessness showed a different orientation, but no physiological disturbances. Normal bone growth in rats has been found to almost cease after 11 days in space, and the mean life span of red blood cells decreases by four days. A series of experiments designed by U.S. scientists will be performed on primates provided and flown by the U.S.S.R. Finally, experiments on board Spacelab will involve determination of the persistence of circadian rhythms in bacteria and humans.

  15. Spaceflight of HUVEC: An Integrated eXperiment- SPHINX Onboard the ISS

    Science.gov (United States)

    Versari, S.; Maier, J. A. M.; Norfini, A.; Zolesi, V.; Bradamante, S.

    2013-02-01

    The spaceflight orthostatic challenge can promote in astronauts inadequate cardiovascular responses defined as cardiovascular deconditioning. In particular, disturbance of endothelial functions are known to lead to altered vascular performances, being the endothelial cells crucial in the maintenance of the functional integrity of the vascular wall. In order to evaluate whether weightlessness affects endothelial functions, we designed, developed, and performed the experiment SPHINX - SPaceflight of HUVEC: an INtegrated eXperiment - where HUVEC (Human Umbilical Vein Endothelial Cells) were selected as a macrovascular cell model system. SPHINX arrived at the International Space Station (ISS) onboard Progress 40P, and was processed inside Kubik 6 incubator for 7 days. At the end, all of the samples were suitably fixed and preserved at 6°C until return on Earth on Soyuz 23S.

  16. Simulated spaceflight effects on mating and pregnancy of rats

    Science.gov (United States)

    Sabelman, E. E.; Chetirkin, P. V.; Howard, R. M.

    1981-01-01

    The mating of rats was studied to determine the effects of: simulated reentry stresses at known stages of pregnancy, and full flight simulation, consisting of sequential launch stresses, group housing, mating opportunity, diet, simulated reentry, and postreentry isolation of male and female rats. Uterine contents, adrenal mass and abdominal fat as a proportion of body mass, duration of pregnancy, and number and sex of offspring were studied. It is found that: (1) parturition following full flight simulation was delayed relative to that of controls; (2) litter size was reduced and resorptions increased compared with previous matings in the same group of animals; and (3) abdominal fat was highly elevated in animals that were fed the Soviet paste diet. It is suggested that the combined effects of diet, stress, spacecraft environment, and weightlessness decreased the probability of mating or of viable pregnancies in the Cosmos 1129 flight and control animals.

  17. Effects of 60-day bed rest with and without exercise on cellular and humoral immunological parameters.

    Science.gov (United States)

    Hoff, Paula; Belavý, Daniel L; Huscher, Dörte; Lang, Annemarie; Hahne, Martin; Kuhlmey, Anne-Kathrin; Maschmeyer, Patrick; Armbrecht, Gabriele; Fitzner, Rudolf; Perschel, Frank H; Gaber, Timo; Burmester, Gerd-Rüdiger; Straub, Rainer H; Felsenberg, Dieter; Buttgereit, Frank

    2015-07-01

    Exercise at regular intervals is assumed to have a positive effect on immune functions. Conversely, after spaceflight and under simulated weightlessness (e.g., bed rest), immune functions can be suppressed. We aimed to assess the effects of simulated weightlessness (Second Berlin BedRest Study; BBR2-2) on immunological parameters and to investigate the effect of exercise (resistive exercise with and without vibration) on these changes. Twenty-four physically and mentally healthy male volunteers (20-45 years) performed resistive vibration exercise (n=7), resistance exercise without vibration (n=8) or no exercise (n=9) within 60 days of bed rest. Blood samples were taken 2 days before bed rest, on days 19 and 60 of bed rest. Composition of immune cells was analyzed by flow cytometry. Cytokines and neuroendocrine parameters were analyzed by Luminex technology and ELISA/RIA in plasma. General changes over time were identified by paired t-test, and exercise-dependent effects by pairwise repeated measurements (analysis of variance (ANOVA)). With all subjects pooled, the number of granulocytes, natural killer T cells, hematopoietic stem cells and CD45RA and CD25 co-expressing T cells increased and the number of monocytes decreased significantly during the study; the concentration of eotaxin decreased significantly. Different impacts of exercise were seen for lymphocytes, B cells, especially the IgD(+) subpopulation of B cells and the concentrations of IP-10, RANTES and DHEA-S. We conclude that prolonged bed rest significantly impacts immune cell populations and cytokine concentrations. Exercise was able to specifically influence different immunological parameters. In summary, our data fit the hypothesis of immunoprotection by exercise and may point toward even superior effects by resistive vibration exercise.

  18. Combining ergometer exercise and artificial gravity in a compact-radius centrifuge

    Science.gov (United States)

    Diaz, Ana; Trigg, Chris; Young, Laurence R.

    2015-08-01

    Humans experience physiological deconditioning during space missions, primarily attributable to weightlessness. Some of these adverse consequences include bone loss, muscle atrophy, sensory-motor deconditioning, and cardiovascular alteration, which may lead to orthostatic intolerance when astronauts return to Earth. Artificial gravity could provide a comprehensive countermeasure capable of challenging all the physiological systems at once, particularly if combined with exercise, thereby maintaining overall health during extended exposure to weightlessness. A new Compact Radius Centrifuge (CRC) platform was designed and built on the existing Short Radius Centrifuge (SRC) at the Massachusetts Institute of Technology (MIT). The centrifuge has been constrained to a radius of 1.4 m, the upper radial limit for a centrifuge to fit within an International Space Station (ISS) module without extensive structural alterations. In addition, a cycle ergometer has been added for exercise during centrifugation. The CRC now includes sensors of foot forces, cardiovascular parameters, and leg muscle electromyography. An initial human experiment was conducted on 12 subjects to analyze the effects of different artificial gravity levels (0 g, 1 g, and 1.4 g, measured at the feet) and ergometer exercise intensities (25 W warm-up, 50 W moderate and 100 W vigorous) on the musculoskeletal function as well as motion sickness and comfort. Foot forces were measured during the centrifuge runs, and subjective comfort and motion sickness data were gathered after each session. Preliminary results indicate that ergometer exercise on a centrifuge may be effective in improving musculoskeletal function. The combination is well tolerated and motion sickness is minimal. The MIT CRC is a novel platform for future studies of exercise combined with artificial gravity. This combination may be effective as a countermeasure to space physiological deconditioning.

  19. Next Steps Toward Understanding Human Habitation of Space: Environmental Impacts and Mechanisms

    Science.gov (United States)

    Globus, Ruth

    2016-01-01

    Entry into low earth orbit and beyond causes profound shifts in environmental conditions that have the potential to influence human productivity, long term health, and even survival. We now have evidence that microgravity, radiation and/or confinement in space can lead to demonstrably detrimental changes in the cardiovascular (e.g. vessel function, orthostatic intolerance), musculoskeletal (muscle atrophy, bone loss) and nervous (eye, neurovestibular) systems of astronauts. Because of both the limited number of astronauts who have flown (especially females) and the high degree of individual variability in the human population, important unanswered questions about responses to the space environment remain: What are the sex differences with respect to specific physiological systems? Are the responses age-dependent and/or reversible after return to Earth? Do observed detrimental changes that resemble accelerated aging progress continuously over time or plateau? What are the mechanisms of the biological responses? Answering these important questions certainly demands a multi-pronged approach, and the study of multicellular model organisms (such as rodents and flies) already has provided opportunities for exploring those questions in some detail. Recent long duration spaceflight experiments with rodents show that mice in space provide a mammalian model that uniquely combines the influence of reduced gravitational loading with increased physical activity. In addition, multiple investigators have shown that ground-based models that simulate aspects of spaceflight (including rodent hind limb unloading to mimic weightlessness and exposure to ionizing radiation), cause various transient and persistent detrimental consequences in multiple physiological systems. In general, we have found that adverse skeletal effects of simulated weightlessness and space radiation when combined, can be quantitatively, if not qualitatively, different from the influence of each environmental

  20. Physiological Health Challenges for Human Missions to Mars

    Science.gov (United States)

    Norsk, Peter

    2015-01-01

    During the next decades, manned space missions are expected to be aiming at the Lagrange points, near Earth asteroids, and Mars flyby and/or landing. The question is therefore: Are we ready to go? To answer this with a yes, we are currently using the International Space Station to develop an integrated human physiological countermeasure suite. The integrated countermeasure suite will most likely encounter: 1) Exercise devices for aerobic, dynamic and resistive exercise training; 2) sensory-motor computer training programs and anti-motion sickness medication for preparing EVAs and G-transitions; 3) lower limb bracelets for preventing and/or treating the VIIP (vision impairment and intracranial pressure) syndrome; 4) nutritional components for maintenance of bone, muscle, the cardiovascular system and preventing oxidative stress and damage and immune deficiencies (e. g. omega-3 fatty acids, PRO/K, anti-oxidants and less salt and iron); 5) bisphosphonates for preventing bone degradation.; 6) lower body compression garment and oral salt and fluid loading for landing on a planetary surface to combat orthostatic intolerance; 7) laboratory analysis equipment for individualized monitoring of biomarkers in blood, urine and saliva for estimation of health status in; 8) advanced ultrasound techniques for monitoring bone and cardiovascular health; and 9) computer modeling programs for individual health status assessments of efficiency and subsequent adjustments of countermeasures. In particular for future missions into deep space, we are concerned with the synergistic effects of weightlessness, radiation, operational constraints and other spaceflight environmental factors. Therefore, increased collaboration between physiological, behavioral, radiation and space vehicle design disciplines are strongly warranted. Another venue we are exploring in NASA's Human Research Program is the usefulness of artificial gravity for mitigating the health risks of long duration weightlessness.

  1. Comparison of bone histomorphometry and μCT for evaluating bone quality in tail-suspended rats

    Science.gov (United States)

    Sun, Lian-Wen; Huang, Yun-Fei; Wang, Ying; Luan, Hui-Qin; Fan, Yu-Bo

    2014-10-01

    Astronauts often suffer from microgravity-induced osteoporosis due to their time in space. Bone histomorphometry, the 'gold standard' technique for detecting bone quality, is widely used in the evaluation of osteoporosis. This study investigates whether μCT has the same application value as histomorphometry in the evaluation of weightlessness-induced bone loss. A total of 24 SD rats were distributed into three groups (n = 8, each): tail-suspension (TS), TS plus active exercise (TSA), and control (CON). After 21 days, bone mineral density (BMD) was measured by dual energy X-ray absorptiometry (DXA) and μCT, and microstructure was measured by μCT and histomorphometry. BMD was found to have decreased significantly in TS and TSA compared with the CON group. The results of the μCT measurements showed that a change in BMD mainly occurred in the trabecular bone, and the trabecular BMD increased significantly in the TSA compared with the TS group. The comparison of μCT and histomorphometry showed that TS led to a significant decrease in bone volume (BV/TV), trabecular thickness (Tb.Th) and trabecular number (Tb.N), and it led to an increase in trabecular separation (Tb.Sp). However, active exercise can prevent these changes. Significant differences in most parameters between TSA and CON were found by μCT but not by histomorphometry. Additionally, the parameters of these two methods are highly correlated. Therefore, the application value of μCT is as good as histomorphometry and DXA in the diagnosis of weightlessness-induced osteoporosis and is even better in evaluating the efficacy of exercise.

  2. Percutaneous aspiration of fluid for management of peritonitis in space

    Science.gov (United States)

    Kirkpatrick, A. W.; Nicolaou, S.; Campbell, M. R.; Sargsyan, A. E.; Dulchavsky, S. A.; Melton, S.; Beck, G.; Dawson, D. L.; Billica, R. D.; Johnston, S. L.; Hamilton, D. R.

    2002-01-01

    BACKGROUND: As a medical emergency that can affect even well-screened, healthy individuals, peritonitis developing during a long-duration space exploration mission may dictate deviation from traditional clinical practice due to the absence of otherwise indicated surgical capabilities. Medical management can treat many intra-abdominal processes, but treatment failures are inevitable. In these circumstances, percutaneous aspiration under sonographic guidance could provide a "rescue" strategy. Hypothesis: Sonographically guided percutaneous aspiration of intra-peritoneal fluid can be performed in microgravity. METHODS: Investigations were conducted in the microgravity environment of NASA's KC-135 research aircraft (0 G). The subjects were anesthetized female Yorkshire pigs weighing 50 kg. The procedures were rehearsed in a terrestrial animal lab (1 G). Colored saline (500 mL) was introduced through an intra-peritoneal catheter during flight. A high-definition ultrasound system (HDI-5000, ATL, Bothell, WA) was used to guide a 16-gauge needle into the peritoneal cavity to aspirate fluid. RESULTS: Intra-peritoneal fluid collections were easily identified, distinct from surrounding viscera, and on occasion became more obvious during weightless conditions. Subjectively, with adequate restraint of the subject and operators, the procedure was no more demanding than during the 1-G rehearsals. CONCLUSIONS: Sonographically guided percutaneous aspiration of intra-peritoneal fluid collections is feasible in weightlessness. Treatment of intra-abdominal inflammatory conditions in spaceflight might rely on pharmacological options, backed by sonographically guided percutaneous aspiration for the "rescue" of treatment failures. While this risk mitigation strategy cannot guarantee success, it may be the most practical option given severe resource limitations.

  3. Pleurodeles waltl, amphibian, Urodele, is a suitable biological model for embryological and physiological space experiments on a vertebrate

    Science.gov (United States)

    Gualandris-Parisot, L.; Husson, D.; Foulquier, F.; Kan, P.; Davet, J.; Aimar, C.; Dournon, C.; Duprat, A. M.

    2001-01-01

    Pleurodeles waltl (amphibian, Urodele) is an appropriate biological model for space experiments on a vertebrate. One reason for interest in this animal concerns the study of the effects of absence of gravity on embryonic development. First, after mating (on Earth) the females retain live, functional sperm in their cloacum for up to 5 months, allowing normal in vivo fertilisation after hormonal stimulation. Second, their development is slow, which allows analyses of all the key stages of ontogenesis from the oocyte to swimming tailbud embryos or larvae. We have performed detailed studies and analyses of the effects of weightlessness on amphibian Pleurodeles embryos, fertilised and allowed to develop until the swimming larvae stage. These experiments were performed in space during three missions on the MIR-station: FERTILE I, FERTILE II and NEUROGENESIS respectively in 1996, 1998 and 1999. We show that in microgravity abnormalities appeared at specific stages of development compared to 1g-centrifuge control embryos and 1g-ground control embryos. In this report we describe abnormalities occurring in the central nervous system. These modifications occur during the neurulation process (delay in the closure of the neural tube and failure of closure of this tube in the cephalic area) and at the early tailbud stage (microcephaly observed in 40% of the microgravity-embryos). However, if acephalic and microcephalic embryos are not taken into account, these abnormalities did not disturb further morphological, biochemical and functional development and the embryos were able to regulate and a majority of normal hatching and swimming larvae were obtained in weightlessness with a developmental time-course equivalent to that of 1g-centrifuge control embryos (on the MIR station) and 1g-ground control embryos.

  4. Building Muscles, Keeping Muscles: Protein Turnover During Space Flight

    Science.gov (United States)

    Ferrando, Arny; Bloomberg, Jacob; Lee, Angie (Technical Monitor)

    2002-01-01

    As we age we lose muscle mass and strength. The problem is a matter of use it or lose it and more - a fact to which any active senior can attest. An imbalance in the natural cycle of protein turnover may be a contributing factor to decreased muscle mass. But the answer is not so simple, since aging is associated with changes in hormones, activity levels, nutrition, and often, disease. The human body constantly uses amino acids to build muscle protein, which then breaks down and must be replaced. When protein turnover gets out of balance, so that more protein breaks down than the body can replace, the result is muscle loss. This is not just the bane of aging, however. Severely burned people may have difficulty building new muscle long after the burned skin has been repaired. Answers to why we lose muscle mass and strength - and how doctors can fix it - may come from space. Astronauts usually eat a well-balanced diet and maintain an exercise routine to stay in top health. During long-duration flight, they exercise regularly to reduce the muscle loss that results from being in a near-weightless environment. Despite these precautions, astronauts lose muscle mass and strength during most missions. They quickly recover after returning to Earth - this is a temporary condition in an otherwise healthy population. Members of the STS-107 crew are participating in a study of the effects of space flight, hormone levels, and stress on protein turnover. When we are under stress, the body responds with a change in hormone levels. Researchers hypothesize that this stress-induced change in hormones along with the near-weightlessness might result in the body synthesizing less muscle protein, causing muscles to lose their strength and size. Astronauts, who must perform numerous duties in a confined and unusual environment, experience some stress during their flight, making them excellent candidates for testing the researchers' hypothesis.

  5. Lung and chest wall mechanics in microgravity.

    Science.gov (United States)

    Edyvean, J; Estenne, M; Paiva, M; Engel, L A

    1991-11-01

    We studied the effect of 15-20 s of weightlessness on lung, chest wall, and abdominal mechanics in five normal subjects inside an aircraft flying repeated parabolic trajectories. We measured flow at the mouth, thoracoabdominal and compartmental volume changes, and gastric pressure (Pga). In two subjects, esophageal pressures were measured as well, allowing for estimates of transdiaphragmatic pressure (Pdi). In all subjects functional residual capacity at 0 Gz decreased by 244 +/- 31 ml as a result of the inward displacement of the abdomen. End-expiratory Pga decreased from 6.8 +/- 0.8 cmH2O at 1 Gz to 2.5 +/- 0.3 cmH2O at Gz (P less than 0.005). Abdominal contribution to tidal volume increased from 0.33 +/- 0.05 to 0.51 +/- 0.04 at 0 Gz (P less than 0.001) but delta Pga showed no consistent change. Hence abdominal compliance increased from 43 +/- 9 to 70 +/- 10 ml/cmH2O (P less than 0.05). There was no consistent effect of Gz on tidal swings of Pdi, on pulmonary resistance and dynamic compliance, or on any of the timing parameters determining the temporal pattern of breathing. The results indicate that at 0 G respiratory mechanics are intermediate between those in the upright and supine postures at 1 G. In addition, analysis of end-expiratory pressures suggests that during weightlessness intra-abdominal pressure is zero, the diaphragm is passively tensed, and a residual small pleural pressure gradient may be present.

  6. Effects of parabolic flight and spaceflight on the endocannabinoid system in humans.

    Science.gov (United States)

    Strewe, Claudia; Feuerecker, Matthias; Nichiporuk, Igor; Kaufmann, Ines; Hauer, Daniela; Morukov, Boris; Schelling, Gustav; Chouker, Alexander

    2012-01-01

    The endocannabinoid system (ECS) plays an important role in the regulation of physiological functions,from stress and memory regulation to vegetative control and immunity. The ECS is considered a central and peripheral stress response system to emotional or physical challenges and acts through endocannabinoids (ECs), which bind to .their receptors inducing subsequent effecting mechanisms. In our studies, the ECS responses have been assessed through blood concentrations of the ECs anandamide and 2-arachidonoylglycerol. In parallel, saliva cortisol was determined and the degree of perceived stress was quantified by questionnaires. This report summarizes the reactivity of the ECS in humans subjected to brief periods of kinetic stress and weightlessness during parabolic flights and to prolonged stress exposure during life onboard the International Space Station (ISS). Both conditions resulted in a significant increase in circulating ECs. Under the acute stress during parabolic flights, individuals who showed no evidence of motion sickness were in low-stress conditions and had a significant increase of plasma ECs. In contrast,highly stressed individuals with severe motion sickness had an absent EC response and a massive increase in hypothalamic-pituitary-adrenal axis activity. Likewise, chronic but well-tolerated exposure to weightlessness and emotional and environmental stressors on the ISS for 6 months resulted in a sustained increase in EC blood concentrations,which returned to baseline values after the cosmonauts'return. These preliminary results suggest that complex environmental stressors result in an increase of circulating ECs and that enhanced EC signaling is probably required for adaptation and tolerance under stressful conditions.

  7. BION-M 1: First continuous blood pressure monitoring in mice during a 30-day spaceflight

    Science.gov (United States)

    Andreev-Andrievskiy, Alexander; Popova, Anfisa; Lloret, Jean-Christophe; Aubry, Patrick; Borovik, Anatoliy; Tsvirkun, Daria; Vinogradova, Olga; Ilyin, Eugeniy; Gauquelin-Koch, Guillemette; Gharib, Claude; Custaud, Marc-Antoine

    2017-05-01

    Animals are an essential component of space exploration and have been used to demonstrate that weightlessness does not disrupt essential physiological functions. They can also contribute to space research as models of weightlessness-induced changes in humans. Animal research was an integral component of the 30-day automated Russian biosatellite Bion-M 1 space mission. The aim of the hemodynamic experiment was to estimate cardiovascular function in mice, a species roughly 3000 times smaller than humans, during prolonged spaceflight and post-flight recovery, particularly, to investigate if mice display signs of cardiovascular deconditioning. For the first time, heart rate (HR) and blood pressure (BP) were continuously monitored using implantable telemetry during spaceflight and recovery. Decreased HR and unchanged BP were observed during launch, whereas both HR and BP dropped dramatically during descent. During spaceflight, BP did not change from pre-flight values. However, HR increased, particularly during periods of activity. HR remained elevated after spaceflight and was accompanied by increased levels of exercise-induced tachycardia. Loss of three of the five mice during the flight as a result of the hardware malfunction (unrelated to the telemetry system) and thus the limited sample number constitute the major limitation of the study. For the first time BP and HR were continuously monitored in mice during the 30-day spaceflight and 7-days of post-flight recovery. Cardiovascular deconditioning in these tiny quadruped mammals was reminiscent of that in humans. Therefore, the loss of hydrostatic pressure in space, which is thought to be the initiating event for human cardiovascular adaptation in microgravity, might be of less importance than other physiological mechanisms. Further experiments with larger number of mice are needed to confirm these findings.

  8. Standing Without Gravity: the Use of Lower Body Negative Pressure for Research and Reconditioning in Spaceflight

    Science.gov (United States)

    Charles, John B.; Campbell, M.R.; Stenger, M.B.; Lee, S.M.C.

    2014-01-01

    Weightlessness during spaceflight causes cephalad redistribution of intravascular and extravascular fluid, provoking cardiovascular and autonomic nervous system adaptations. The resulting functional state is appropriate for weightlessness but can result in orthostatic hypotension and intolerance during and after return to a persistent acceleration or gravitational environment. Lower body negative pressure (LBNP) applies subambient air pressure to the legs and lower abdomen inside a volume sealed at the waist, and decompression by 40-50 mmHg reverses the spaceflight-induced cephalad shift. LBNP has been used both to test the state of cardiovascular system during spaceflight and as a countermeasure by all space-faring nations. Two configurations have thus far been used in spaceflight since the first LBNP flew on the first Soviet Salyut station in 1971. The Soviet and Russian configuration, used in four Salyut stations, the Mir space station and the Russian segment of the International Space Station, has no saddle to support the body so during decompression the feet press against the bottom of the collapsible chamber which shortens and applies force against the feet proportional to the decompression level. Thus, activation of the skeletal musculature partially counteracts vascular and venous pooling in the enclosed body segments, stimulating the orthostatic compensatory mechanisms as they would be standing on Earth. In the American configuration, used aboard Skylab and the Space Shuttle, a saddle supported the astronaut so the feet did not contact the bottom of the chamber, and vascular engorgement was not countered by muscular contraction. This minimized skeletal muscle involvement, unmasked vascular compensatory mechanisms for research purposes, and allowed measurements of changes in leg volume and muscle sympathetic nerve activity. Both variants have demonstrated research and therapeutic value in appropriately designed protocols. LBNP continues to be used for

  9. Study on the pyrolysis characteristics of refuse derived fuel from village solid waste%城郊乡村生活垃圾衍生燃料热解特性研究

    Institute of Scientific and Technical Information of China (English)

    陈江; 章旭明

    2012-01-01

    将城郊乡村生活垃圾加工成粒径6.0 mm左右的垃圾衍生燃料(RDF),采用热重(TG)分析和红外光谱等研究其热解特性.结果表明:(1)在RDF挥发分阶段和生物质挥发分阶段,助燃添加剂处于活泼分解阶段,加入了30%(质量分数)秸秆、玉米芯等生物质作助燃添加剂后的RDF(以下简写为混合RDF)分子碎片正发生内部氢重排,总体挥发分产物较多,并且有明显的二次裂解,失重提高到4.85 mg,失重率约提高12%.在RDF与生物质重叠的碳固定阶段,助燃添加剂失重率有一定提高,热重微分(DTG)峰值速率增加,为RDF碳固定阶段的进一步热解提供了良好的支持.(2)快加热产气速率均大于慢加热.(3)热解终温越高,越有利气体析出.(4)RDF的热解固体产率随着热解终温的升高而降低,在850℃时为31.9%;热解气体产率随着热解终温升高而迅速升高,在850℃时可达49.8%.(5)根据红外光谱图,城郊乡村生活垃圾加工成的RDF中所含的氯元素基本上以HCl形式释放.(6)一级动力学反应可以准确地描述物料热解过程.%The village solid waste was processing into the refuse derived fuel (RDF) granules of diameter 6. 0 mm. The pyrolysis characteristics of RDF were studied with the help of thermal gravity analyzer and Fourier trans form infrared spectroscopy (FTIR). In the devolatilization period of RDF and biomass.the combustion-supporting a gent was in the rapid decomposition period; adding 30% (mass ratio) of straw in RDF,the obtained compound RDF presented better pyrolysis characteristics than original RDF, the velocity product was greatly increased because of the internal rearrangement of hydrogen in molecular fragments; there was a significant secondary cracking found in com pound RDF,the weightless rised to 4. 85 mg and the weightless rate increased by about 12%. In the overlapping car bon fixation stage of RDF and biomass,the weightless rate of combustion-supporting agent was

  10. Tetanic contraction induces enhancement of fatigability and sarcomeric damage in atrophic skeletal muscle and its underlying molecular mechanisms.

    Science.gov (United States)

    Yu, Zhi-Bin

    2013-11-01

    Muscle unloading due to long-term exposure of weightlessness or simulated weightlessness causes atrophy, loss of functional capacity, impaired locomotor coordination, and decreased resistance to fatigue in the antigravity muscles of the lower limbs. Besides reducing astronauts' mobility in space and on returning to a gravity environment, the molecular mechanisms for the adaptation of skeletal muscle to unloading also play an important medical role in conditions such as disuse and paralysis. The tail-suspended rat model was used to simulate the effects of weightlessness on skeletal muscles and to induce muscle unloading in the rat hindlimb. Our series studies have shown that the maximum of twitch tension and the twitch duration decreased significantly in the atrophic soleus muscles, the maximal tension of high-frequency tetanic contraction was significantly reduced in 2-week unloaded soleus muscles, however, the fatigability of high-frequency tetanic contraction increased after one week of unloading. The maximal isometric tension of intermittent tetanic contraction at optimal stimulating frequency did not alter in 1- and 2-week unloaded soleus, but significantly decreased in 4-week unloaded soleus. The 1-week unloaded soleus, but not extensor digitorum longus (EDL), was more susceptible to fatigue during intermittent tetanic contraction than the synchronous controls. The changes in K+ channel characteristics may increase the fatigability during high-frequency tetanic contraction in atrophic soleus muscles. High fatigability of intermittent tetanic contraction may be involved in enhanced activity of sarcoplasmic reticulum Ca(2+)-ATPase (SERCA) and switching from slow to fast isoform of myosin heavy chain, tropomyosin, troponin I and T subunit in atrophic soleus muscles. Unloaded soleus muscle also showed a decreased protein level of neuronal nitric oxide synthase (nNOS), and the reduction in nNOS-derived NO increased frequency of calcium sparks and elevated

  11. Effects of Simulated Microgravity on Otolith Growth of Larval Zebrafish using a Rotating-Wall Vessel: Appropriate Rotation Speed and Fish Developmental Stage

    Science.gov (United States)

    Li, Xiaoyan; Anken, Ralf; Liu, Liyue; Wang, Gaohong; Liu, Yongding

    2017-02-01

    Stimulus dependence is a general feature of developing animal sensory systems. In this respect, it has extensively been shown earlier that fish inner ear otoliths can act as test masses as their growth is strongly affected by altered gravity such as hypergravity obtained using centrifuges, by (real) microgravity achieved during spaceflight or by simulated microgravity using a ground-based facility. Since flight opportunities are scarce, ground-based simulators of microgravity, using a wide variety of physical principles, have been developed to overcome this shortcoming. Not all of them, however, are equally well suited to provide functional weightlessness from the perspective of the biosystem under evaluation. Therefore, the range of applicability of a particular simulator has to be extensively tested. Earlier, we have shown that a Rotating-Wall Vessel (RWV) can be used to provide simulated microgravity for developing Zebrafish regarding the effect of rotation on otolith development. In the present study, we wanted to find the most effective speed of rotation and identify the appropriate developmental stage of Zebrafish, where effects are the largest, in order to provide a methodological basis for future in-depth analyses dedicated to the physiological processes underlying otolith growth at altered gravity. Last not least, we compared data on the effect of simulated microgravity on the size versus the weight of otoliths, since the size usually is measured in related studies due to convenience, but the weight more accurately approximates the physical capacity of an otolith. Maintaining embryos at 10 hours post fertilization for three days in the RWV, we found that 15 revolutions per minute (rpm) yielded the strongest effects on otolith growth. Maintenance of Zebrafish staged at 10 hpf, 1 day post fertilization (dpf), 4 dpf, 7 dpf and 14 dpf for three days at 15 rpm resulted in the most prominent effects in 7 dpf larvae. Weighing versus measuring the size of otoliths

  12. Mouse Behavior on ISS: The Emergence of a Distinctive, Organized Group Circling Behavior Unique to Spaceflight

    Science.gov (United States)

    Ronca, A. E.; Moyer, E. L.; Talyansky, Y.; Solomides, P.; Choi, S.; Gong, C.; Globus, R. K.

    2017-01-01

    As interest in long duration effects of space habitation increases, understanding the behavior of model organisms living within the habitats engineered to fly them is vital for designing, validating, and interpreting future spaceflight studies. Only a handful of papers have previously reported behavior of mice and rats in the weightless environment of space (Andreev-Andrievskiy, et al., 2013; Cancedda et al., 2012; Ronca et al., 2008). The Rodent Research Hardware and Operations Validation Mission (Rodent Research-1; RR1) utilized the Rodent Habitat (RH) developed at NASA Ames Research Center to fly mice on the ISS. Ten adult (16-week-old) female C57BL6J mice were launched on September 21st, 2014 in an unmanned Dragon Capsule, and spent 37 days in flight. Here we report group behavioral phenotypes of the RR1 Flight (FLT) and environment-matched Ground Control (GC) mice in the RH during this long duration flight. Video was recorded for 34 days on the ISS, permitting daily assessments of overall health and well being of the mice, and providing a valuable repository for detailed behavioral analysis. As compared to GC mice, RR1 FLT mice exhibited the same range of behaviors, including eating, drinking, exploration, self- and allogrooming, and social interactions at similar or greater levels of occurrence. Overall activity was greater in FLT as compared to GC mice, with spontaneous ambulatory behavior, including organized circling or race-tracking behavior that emerged within the first few days of flight following a common developmental sequence, comprising the primary dark cycle activity of FLT mice. Circling participation by individual mice persisted throughout the mission. Analysis of group behavior over mission days revealed recruitment of mice into the group phenotype, coupled with decreasing numbers of collisions between circling mice. This analysis provides insights into the behavior of mice in microgravity, and clear evidence for the emergence of a distinctive

  13. Study on bok choy' fresh preserving technology%青菜贮藏保鲜工艺研究

    Institute of Scientific and Technical Information of China (English)

    梁凤玲; 王武; 杨妍; 吴巧

    2012-01-01

    研究6-苄氨基腺嘌呤(6-BA)浓度、C102浓度、CaCl2浓度及浸泡处理时间等工艺参数对青菜贮藏期间失重率、呼吸强度、维生素C含量、褐变度和感官品质的影响。结果表明,影响青菜贮藏期品质的因素主次为:6-BA浓度〉C102浓度〉CaCl2浓度〉浸泡处理时间;较优的青菜保鲜工艺为:6-BA浓度为25mg/L、C102浓度为20mg,LJ、CaCl2为1%(W/V)、浸泡处理时间为20min。该工艺可显著降低青菜贮藏期间的失重率,减缓维生素C的减少,延缓蔬菜叶片褐变,延长货架期。%Effects of addition amount of 6-Benzylaminopurine (6-BA),chlorine dioxide,calcium chloride and soak time on weightlessness rate,respiratory intensity,vitamin C content,browning intensity and organoleptic evaluation of bok choy were investigated, The effect on quality characteristics of bok choy during storage from strong to weak was 6-BA,chlorine dioxide,calcium chloride and soak time. The optimal strategy for preserving bok choy were 25mg/L 6-BA,20mg/L chlorine dioxide, 1% calcium chloride for 20min. The treatment significantly reduced the bok choy's weightlessness rate in storage,slowed down the reduction of vitamin C,delayed the degree of bok choy's browning,and prolonged the shelf life.

  14. Studies on low concentration of dust emission test in coal -fired flue gas%燃煤烟气低浓度粉尘排放测试的研究

    Institute of Scientific and Technical Information of China (English)

    杨丁; 陈威祥; 郑芳

    2015-01-01

    GB/T 16157-1996中推荐的采样测试方法,仅适用于颗粒物浓度高于50 mg/m3的固定污染源采样。伴随着排放标准的提高,污染物控制技术与工艺日趋完善,部分示范工程颗粒物排放在线数据显示低于1 mg/m3,沿用原方法采样经常出现样品失重现象,从而无法得到烟气中真实的低浓度粉尘排放浓度。经多次试验研究,通过采用一体式低浓度采样头和大流量采样泵,增加采样体积、预留空白样、选用优质滤膜、对采样枪进行伴热改造等措施,针对低浓度排放测试的准确性和可靠性得到很大的提高,该法已在实际工程上得到应用,为我国颗粒物低排放测试技术的规范与成熟提供借鉴。%The traditional testing method mentioned in GB /T 16157-1996 only apply to stationary source with more than 50 mg/m3 particulate concentration.Pol ution control technologies and processes are maturing with the strict emission standards, the online data of some demonstration projects show the emissions of particulate are less than 1 mg/m3 .There are often occurring weightlessness phenomenon if fol owing the traditional testing methods, thus it cannot get real concentration of dust emission in flue gas.Through repeated experiments and practice, the weightlessness problem can be effectively solved by using one-piece sampling-head and high flow sampling pump, increasing the sampling volume, reserving blank samples, choosing high-quality filter membrane and heating sampling gun, and the accuracy and reliability have been greatly improved.The method has been applied in practical engineering, provided reference for practical engineering.

  15. 不同处理对草莓保鲜效果的影响%Effect of Different Treatments on the Fresh-keeping of Strawberry

    Institute of Scientific and Technical Information of China (English)

    姜华

    2011-01-01

    [Objective ] The research aimed to study the physiological and biochemical changes of strawberry during the fresh-keeping process. [ Method ] Taking strawberry as test materials, 1 -MCP, chitosan composite solution, spices extract solution were used to treat straw berry and the strawberry were stored in low temperature controlled air storage. The decay index, weightless rate, respiratory, Vc content and MDA content of strawberry were determined to study the effects of different treatments on the fresh-keeping of strawberry. [ Result] The decay index, weightless rate, respiratory, MDA content of strawberries of 1-MCP group, chitosan composite solution group, spices extract solution group were higher compared with the control(CK) , Vc content, total sugar and total acid were lower than control group after storage 13 days, with significant difference ( P < 0.05 ). Shelf-life of strawberry was prolonged in 4 t low temperature controlled air storage. [ Conclusion] The research provided certain theoretical basis for the storage and fresh-keeping of strawberry.%[目的]研究草莓在贮藏保鲜过程中的生理生化变化.[方法]以草莓为试验材料,分别采用1 - MCP、壳聚糖复合涂膜、香辛料提取液对其进行处理后,置于低温气调库中进行贮藏,对草莓的腐烂率、失重率、呼吸强度、Vc含量及丙二醛含量进行测定,研究不同处理方式对草莓的保鲜效果.[结果]贮藏13d时,1- MCP、壳聚糖复合涂膜、香辛料提取液处理的草莓的腐烂指数、失重率、呼吸强度、MDA含量比空白组(CK组)低,Vc含量、总糖、总酸高于空白组,差异均达到显著水平(P<0.05).草莓在低温4℃条件下的贮藏保鲜时间被延长.[结论]该研究为草莓贮藏保鲜提供一定的理论依据.

  16. Thermal degradation kinetics of semi-dulling polyester chips with Sb/Ti catalyst%Sb/Ti复配催化半光聚酯热降解动力学研究

    Institute of Scientific and Technical Information of China (English)

    戴钧明; 王玉合; 张忠安; 王树霞; 司虎

    2016-01-01

    The thermal degradation kinetics of semi - dulling polyester chips was studied systematically through the methods of TGA, Friedman and Chang under nitrogen atmosphere ( with five different compound cata-lysts matching ratios:Sb/Ti=100/0 , 75/25 , 50/50 , 25/75 and 0/100 ) . The results of TGA showed that the de-composition temperature of Ti-catalyst polyester was higher than that of Sb-catalyst polyester at weightlessness 1%, and other polyester’ s decomposition temperatures were in the temperature range between Ti-catalyst polyes-ter’s and Sb-catalyst polyester’s. And the decomposition temperature of Ti-catalyst polyester was the lowest one at weightlessness 5% ~50%, other polyester’ s temperatures were all approaching the decomposition temperature of Sb-catalyst polyester’ s temperature. The results of thermal degradation kinetic suggested that the decomposition reaction series n, decomposition activation energy E all manifest their declining trend with Ti’ s proportion increas-ing, which mean the thermal stability of the polyester declines.%通过热失重( TGA)、Friedman方法、Chang方法系统研究了5种Sb/Ti复配催化剂( Sb/Ti配比分别为:100/0、75/25、50/50、25/75、0/100)合成半光聚酯PET(聚对苯二甲酸乙二醇酯)于氮气气氛下的热稳定性能及热降解动力学。热失重研究表明:失重1%时全钛聚酯失重温度比全锑的高,其他复配比例聚酯的失重温度处于二者之间;失重5%~50%时的失重温度,复配的均与锑相当,全钛的最低;通过Friedman法和Chang法求得热降解动力学参数:分解反应活化能E和反应级数n,结果表明,随着Sb/Ti复配催化剂中Ti比例的升高,E和n均呈下降趋势,聚酯的热稳定性下降。

  17. On the instabilities in miscible fluids under horizontal oscillating forcing

    Science.gov (United States)

    Shevtsova, Valentina; Gaponenko, Yuri; Mialdun, Aliaksandr

    2012-07-01

    In this research the attention is focused on the mass transfer under vibrations. The pure vibrational effect can be observed in weightlessness only. However, experimental studies addressing vibrational phenomena in weightlessness are very limited. This study was initiated by preparation of VIPIL proposal in the response of ESA AO-2009 call and will continue in the frame of the preparation the experiment VIPIL on the ISS. The current research is an attempt to provide experimental and numerical evidence for the instability in miscible fluids in the case of horizontal vibrations parallel to the interface. We present the results of the pioneer experiment SOVICON on the observation of the interface behavior between miscible liquids and vibrational convection in reduced gravity, conducted in the 49th Parabolic Flight Campaigns organized by the European Space Agency. Two miscible liquid mixtures, water and isopropanol of different concentrations, are placed in a closed cell, submitted to horizontal and sinusoidal oscillations at different frequencies and amplitudes. For the certain set of control parameters the localized mean convective flows are emerged in the vicinity of the triple points: the contact point between solid vertical wall and two liquids. These localized convective patterns spread along the solid walls and provide a local mixing along the walls. This type of instability was studied numerically in the averaged approach for high frequency vibrations [1], [2]. During the microgravity experiments we observed another type of instability in the form of standing waves. Above a threshold, a relief appears at the interface between the two fluids. This instability occurs when the vibration amplitude and frequency are above a critical value which is set by the level of viscous dissipation in the liquid. In general, this viscous dissipation will have a few sources: motion in the bulk of the liquid, motion near the boundaries of the liquid container, motion of any

  18. DARA vestibular equipment onboard MIR.

    Science.gov (United States)

    Hofmann, P; Kellig, A; Hoffmann, H U; Ruyters, G

    1998-01-01

    In space, the weightless environment provides a different stimulus to the otolith organs of the vestibular system, and the resulting signals no longer correspond with the visual and other sensory signals sent to the brain. This signal conflict causes disorientation. To study this and also to understand the vestibular adaptation to weightlessness, DARA has developed scientific equipment for vestibular and visuo-oculomotoric investigations. Especially, two video-oculography systems (monocular--VOG--and binocular--BIVOG, respectively) as well as stimuli such as an optokinetic stimulation device have successfully been employed onboard MIR in the frame of national and European missions since 1992. The monocular VOG was used by Klaus Flade during the MIR '92 mission, by Victor Polyakov during his record 15 months stay onboard MIR in 1993/94 as well as by Ulf Merbold during EUROMIR '94. The binocular version was used by Thomas Reiter and Sergej Avdeyev during the 6 months EUROMIR '95 mission. PIs of the various experiments include H. Scherer and A. Clarke (FU Berlin), M. Dieterichs and S. Krafczyk (LMU Munchen) from Germany as well as C.H. Markham and S.G. Diamond from the United States. Video-Oculography (VOG) is a technique for examining the function of the human balance system located in the inner ear (vestibular system) and the visio-oculomotor interactions of the vestibular organ. The human eye movements are measured, recorded and evaluated by state-of-the-art video techniques. The method was first conceived and designed at the Vestibular Research Laboratory of the ENT Clinic in Steglitz, FU Berlin (A. Clarke, H. Scherer). Kayser-Threde developed, manufactured and tested the facilities for space application under contract to DARA. Evaluation software was first provided by the ENT Clinic, Berlin, later by our subcontractor Sensomotoric Instruments (SMI), Teltow. Optokinetic hardware to support visuo-oculomotoric investigations, has been shipped to MIR for EUROMIR '95

  19. The thermo-vibrational convection in microgravity condition. Ground-based modelling.

    Science.gov (United States)

    Zyuzgin, A. V.; Putin, G. F.; Harisov, A. F.

    In 1995-2000 at orbital station "Mir" has been carried out the series of experiments with the equipment "Alice" for the studying regimes of heat transfer in the supercritical fluids under influence inertial microaccelerations. The experiments have found out existence of the thermo-vibrational and thermo-inertial convective movements in the real weightlessness[1] and controlling microgravity fields[2]. However regarding structures of thermovibrational convection the results of experiments have inconsistent character. Therefore carrying out the ground-based modeling of the given problem is actually. In this work in laboratory conditions were investigated the thermo-vibrational convective movements from the dot heat source at high-frequency vibrations of the cavity with the fluid and presence quasi-static microacceleration. As the result of ground-based modeling, the regimes of convective flows, similar observed in the space experiment are received. Evolution of the convective structures and the spatial-temporary characteristics of movements are investigated in a wide range of the problem parameters. The control criteria and its critical value are determined. The received results well coordinated to the data of space experiments and allow adding and expanding representation about thermo-vibrational effects in conditions of real weightlessness and remove the contradictions concerning structures thermo-vibrational convective flows, received at the analysis of the given orbital experiments. The research described in this publication was made possible in part by Russian Foundation for Basic Research and Administration of Perm Region, Russia, under grant 04-02-96038, and Award No. PE-009-0 of the U.S. Civilian Research & Development Foundation for the Independent States of the Former Soviet Union (CRDF). A.V. Zyuzgin, A. I. Ivanov, V. I. Polezhaev, G. F. Putin, E. B. Soboleva Convective Motions in Near-Critical Fluids under Real Zero-Gravity Conditions. Cosmic Research

  20. Effects of Simulated Microgravity on Otolith Growth of Larval Zebrafish using a Rotating-Wall Vessel: Appropriate Rotation Speed and Fish Developmental Stage

    Science.gov (United States)

    Li, Xiaoyan; Anken, Ralf; Liu, Liyue; Wang, Gaohong; Liu, Yongding

    2016-10-01

    Stimulus dependence is a general feature of developing animal sensory systems. In this respect, it has extensively been shown earlier that fish inner ear otoliths can act as test masses as their growth is strongly affected by altered gravity such as hypergravity obtained using centrifuges, by (real) microgravity achieved during spaceflight or by simulated microgravity using a ground-based facility. Since flight opportunities are scarce, ground-based simulators of microgravity, using a wide variety of physical principles, have been developed to overcome this shortcoming. Not all of them, however, are equally well suited to provide functional weightlessness from the perspective of the biosystem under evaluation. Therefore, the range of applicability of a particular simulator has to be extensively tested. Earlier, we have shown that a Rotating-Wall Vessel (RWV) can be used to provide simulated microgravity for developing Zebrafish regarding the effect of rotation on otolith development. In the present study, we wanted to find the most effective speed of rotation and identify the appropriate developmental stage of Zebrafish, where effects are the largest, in order to provide a methodological basis for future in-depth analyses dedicated to the physiological processes underlying otolith growth at altered gravity. Last not least, we compared data on the effect of simulated microgravity on the size versus the weight of otoliths, since the size usually is measured in related studies due to convenience, but the weight more accurately approximates the physical capacity of an otolith. Maintaining embryos at 10 hours post fertilization for three days in the RWV, we found that 15 revolutions per minute (rpm) yielded the strongest effects on otolith growth. Maintenance of Zebrafish staged at 10 hpf, 1 day post fertilization (dpf), 4 dpf, 7 dpf and 14 dpf for three days at 15 rpm resulted in the most prominent effects in 7 dpf larvae. Weighing versus measuring the size of otoliths