Space Station Astronauts Research Articles

Gene expression changes reveal the impact of the space environment on the skin of International Space Station astronauts.

The various types of ionizing radiation and altered gravity in the space environment present a risk to humans during space missions. Changes in the space environment lead to skin diseases, affecting the status of the aviators to fly. Therefore, it is important to explore the molecular-level changes in the skin during space missions. Bioinformatics analysis of gene arrays from hair follicle tissue of 10 astronauts was performed to explore changes in gene expression before, during and after space missions. First, STEM (Short Time-series Expression Miner) software was used to identify the expression patterns of hair follicle genes of astronauts pre-, in- and postflight. Gene Ontology Enrichment Analysis was then performed to explore the gene functions within the module. Protein-protein interaction network analysis was performed on skin-related genes. The transcriptional regulatory network within the module was constructed using the TRRUST database. The circadian rhythm-related genes within the module were screened using the MSigDB (Molecular Signatures Database). Based on differential expression analysis between the two groups, there were 327 differentially expressed genes after the astronauts entered space compared with preflight, and only 54 differentially expressed genes after returning to Earth. This outcome suggests that the expression of most genes can be recovered on return to the ground, but there are a small number of genes whose expression cannot be recovered in a short period of time. Based on time series analysis, 311 genes showed increased expression on entry into space and decreased expression on return to Earth. The genes of this expression pattern were associated with skin development, keratinocyte differentiation and cornification. Ten hub genes were identified as skin-related genes within the module, as well as nine transcription factors and three circadian genes. One hundred and seventy-nine genes decreased in expression after entry into space and increased on return to Earth. By reviewing the literature, we found that four of the genes, CSCD2, HP, CXCR1 and SSTR4, are associated with skin diseases. Through bioinformatics analysis, we found that the space environment affects skin keratinocyte differentiation, leading to skin barrier damage and inflammatory responses, and that this effect was decreased after return to Earth.

Integrated Valve Product Fluid Simulation and Test Verification

The integrated valve product’s main function is to electrolytic oxygen generation subsystem to produce hydrogen and oxygen to realize automatic discharge, to maintain the space station astronauts in orbit around in comfort and safety, high reliability, easy maintenance, and the device should be easy replacement of human-computer ergonomics requirements to ensure long-term on-orbit operation station. Based on the above requirements, an integrated valve product based on environmental control and a health protection system is designed. The integrated product includes hydrogen normal and backup emission branches, oxygen normal and backup emission branches. Through fluid simulation and experimental verification, it is verified that the flow rate and other key indicators of the integrated valve product meet the requirements, which has certain reference and guiding significance for the design of similar integrated products in the future.

Space Omics and Tissue Response in Astronaut Skeletal Muscle after Short and Long Duration Missions.

The molecular mechanisms of skeletal muscle adaptation to spaceflight are as yet not fully investigated and well understood. The MUSCLE BIOPSY study analyzed pre and postflight deep calf muscle biopsies (m. soleus) obtained from five male International Space Station (ISS) astronauts. Moderate rates of myofiber atrophy were found in long-duration mission (LDM) astronauts (~180 days in space) performing routine inflight exercise as countermeasure (CM) compared to a short-duration mission (SDM) astronaut (11 days in space, little or no inflight CM) for reference control. Conventional H&E scout histology showed enlarged intramuscular connective tissue gaps between myofiber groups in LDM post vs. preflight. Immunoexpression signals of extracellular matrix (ECM) molecules, collagen 4 and 6, COL4 and 6, and perlecan were reduced while matrix-metalloproteinase, MMP2, biomarker remained unchanged in LDM post vs. preflight suggesting connective tissue remodeling. Large scale proteomics (space omics) identified two canonical protein pathways associated to muscle weakness (necroptosis, GP6 signaling/COL6) in SDM and four key pathways (Fatty acid β-oxidation, integrin-linked kinase ILK, Rho A GTPase RHO, dilated cardiomyopathy signaling) explicitly in LDM. The levels of structural ECM organization proteins COL6A1/A3, fibrillin 1, FBN1, and lumican, LUM, increased in postflight SDM vs. LDM. Proteins from tricarboxylic acid, TCA cycle, mitochondrial respiratory chain, and lipid metabolism mostly recovered in LDM vs. SDM. High levels of calcium signaling proteins, ryanodine receptor 1, RyR1, calsequestrin 1/2, CASQ1/2, annexin A2, ANXA2, and sarco(endo)plasmic reticulum Ca(2+)-ATPase (SERCA1) pump, ATP2A, were signatures of SDM, and decreased levels of oxidative stress peroxiredoxin 1, PRDX1, thioredoxin-dependent peroxide reductase, PRDX3, or superoxide dismutase [Mn] 2, SOD2, signatures of LDM postflight. Results help to better understand the spatiotemporal molecular adaptation of skeletal muscle and provide a large scale database of skeletal muscle from human spaceflight for the better design of effective CM protocols in future human deep space exploration.

Comparison of Dural Venous Sinus Volumes Before and After Flight in Astronauts With and Without Spaceflight-Associated Neuro-Ocular Syndrome

Spaceflight-associated neuro-ocular syndrome (SANS) occurs in 40% to 60% of National Aeronautics and Space Administration (NASA) International Space Station (ISS) astronauts who present postflight with ophthalmological findings and elevated intracranial pressure. The etiology of SANS is unknown; it is hypothesized that venous outflow congestion from the head and neck occurs because of microgravity, which is supported by the finding of internal jugular vein stagnant flow and thrombosis in some astronauts, but the impact on intracranial dural venous sinus structures remains unknown. To clarify the potential risk of retrograde extension of clot intracranially among astronauts with internal jugular venous thrombosis by evaluating intracranial venous structures following spaceflight and to assess for any association between intracranial venous congestion and SANS. This retrospective cohort study of all NASA astronauts who had undergone magnetic resonance (MR) venography at the time of the study included quantitative and qualitative assessments of the intracranial venous system on preflight and postflight MR venograms. Data were collected a mean (SD) of 525.8 (187.5) days before spaceflight and 2.0 (1.5) days after return to Earth. A semiautomated segmentation of the venogram images was used, which was then compared with a neuroradiologist's assessment. A mean (SD) 184.3 (66.0) days of ISS spaceflight missions. Dural venous sinus volumes before and after spaceflight. A total of 12 astronauts (2 [16.67%] women; 10 [83.33%] men), with a mean (SD) age of 47.8 (5.8) years, were included. Overall, 4 astronauts (33.33%) met the diagnostic criteria for SANS. No dural venous sinus thrombosis was detected for any astronaut. Astronauts with SANS had significantly greater median (range) preflight to postflight increases in volume vs astronauts without SANS for all 3 venous sinus structures: superior sagittal sinus (13.40% [8.70% to 17.47%] vs -2.66% [-15.84% to 5.31%,]; P = .004), right transverse/sigmoid sinus (17.15% [7.63% to 30.08%] vs 0.77% [-14.98% to 15.12%]; P = .02), and left transverse/sigmoid sinus (9.40% [5.20% to 15.50%] vs -1.40% [-14.20% to 12.50%]; P = .03). There was a positive correlation between the neuroradiologist's evaluation and the semiautomated method for the superior sagittal sinus (rpb = 0.64; P = .02) and the right transverse/sigmoid sinus (rpb = 0.58; P = .050). These findings, in conjunction with the growing body of evidence of abnormal blood flow dynamics during spaceflight, suggest an association between intracranial venous congestion and SANS. Thus, there is an implication that individuals with increased venous sinus compliance may be at increased risk of developing SANS. These findings should be confirmed in a larger astronaut population and may contribute to understanding disorders of intracranial venous outflow on Earth.

Object-Process Methodology as an Alternative to Human Factors Task Analysis.

We define and demonstrate the use of OPM-TA-a model-based task analysis (TA) framework that uses object-process methodology (OPM) ISO 19450 as a viable alternative to traditional TA techniques. A variety of different TA methods exist in human factors engineering, and several of them are often applied successively for a broad task representation, making it difficult to follow. Using OPM-TA, we modeled how an International Space Station (ISS) astronaut would support extravehicular activities using the existing robotic arm workstation with a new control panel and an electronic procedure system. The modeling employed traditional TA methods and the new OPM-TA approach, enabling a comparison between them. While the initial stages of modeling with OPM-TA follow those of traditional TA, OPM-TA modeling yields an executable and logically verifiable model of the entire human-robot system. Both OPM's hierarchical set of diagrams and the equivalent, automatically generated statements in a subset of natural language text specify how objects and processes relate to each other at increasingly detailed levels. The graphic and textual OPM modalities specify the system's architecture, which enables its function and benefits its users. To verify the model logical correctness model, we executed it using OPM's simulation capability. OPM-TA was able to unify traditional TA methods and expand their capabilities. The formal yet intuitive OPM-TA approach fuses and extends traditional TA methods, which are not amenable to simulation. It therefore can potentially become a widely used means for TA and human-machine procedure development and testing.

Spaceflight-Associated Changes in the Opacification of the Paranasal Sinuses and Mastoid Air Cells in Astronauts

Head congestion is one of the most common somatic symptoms experienced by astronauts during spaceflight; however, changes in the opacification of the paranasal sinuses or mastoid air cells in astronauts have not been adequately studied. To quantify preflight to postflight changes in the opacification of the paranasal sinuses and mastoid air cells in Space Shuttle astronauts and International Space Station (ISS) astronauts and to assess whether there are differences between the 2 groups of astronauts. This cohort study examined preflight and postflight head magnetic resonance images (MRIs) of 35 astronauts who had participated in either a short-duration (≤30 days) Space Shuttle mission or a long-duration (>30 days) ISS mission and had undergone both preflight and postflight MRI. Images were obtained before and after spaceflight. Images were evaluated by 2 neuroradiologists blinded to which mission each astronaut had flown and to which images were preflight or postflight images. Spaceflight on the Space Shuttle or the ISS. Measured outcomes included preflight to postflight changes in Lund-Mackay scores for the paranasal sinuses and in scores grading mastoid effusions. Most astronauts in both the Space Shuttle group (n = 17; 15 men; mean [SD] age at launch, 47.7 [3.1] years) and the ISS group (n = 18; 14 men; mean [SD] age at launch, 48.6 [4.7] years) exhibited either no change or a reduction in paranasal sinus opacification as seen on postflight MRI scans (Space Shuttle group: 6 [35.3%] had no sinus opacification before or after spaceflight, 5 [29.4%] had less sinus opacification after spaceflight, 3 [17.6%] had the same amount of sinus opacification before and after spaceflight, and 3 [17.6%] had increased paranasal sinus opacification after spaceflight; ISS group: 8 [44.4%] had no sinus opacification before or after spaceflight, 4 [22.2%] had less sinus opacification after spaceflight, 1 (5.6%) had the same amount of sinus opacification before and after spaceflight, and 5 [27.8%] had scores consistent with increased paranasal sinus opacification after spaceflight). Long-duration spaceflight (ISS group) was associated with an increased risk of mastoid effusion relative to short-duration spaceflight (relative risk, 4.72; 95% CI, 1.2-18.5). Images were obtained a mean (SD) 287.5 (208.6) days (range, 18-627 days) prior to and 6.8 (5.8) days (range, 1-20 days) after spaceflight. Astronauts had undergone either a mean (SD) of 13.6 (1.6) days of spaceflight on the Space Shuttle (17 astronauts) or 164.8 (18.9) days on the ISS (18 astronauts). This study found that exposure to spaceflight conditions on the ISS is associated with an increased likelihood for the formation of mastoid effusions. There was no association between exposure to spaceflight conditions and changes in paranasal sinus opacification. The limitations of this study include lack of information concerning medical history and mission-specific operational experience for individual astronauts. Further studies are indicated to determine the cause and composition of the mastoid effusions.

RADIATION EXPOSURE DURING THE ORBITAL AND INTERPLANETARY SPACEFLIGHTS: MONITORING AND PROTECTION

This review presents actual knowledge and recent findings on the main sources of radiation exposure on human in space: galactic cosmic rays, Earth radiation belts and solar cosmic rays. Doses of radiation on the space station are in ~200 times higher than the average human exposure in ordinary terrestrial conditions. During yearlong flight on the International space station (ISS) astronaut receives a dose, which exceeds the limits in approximately 10 times (200 mSv/year) for nuclear industry worker. There is a further transformation of cosmic radiation field inside the body of the astronaut at the expense of organs' "self-shielding". These changes should be taken into account to estimate dose exposure on organs and effective dose. In order to compare with the standards the doses for the critical organs must be measured with the help of tissue-equivalent phantoms dummies. Authors consider such problems as phantom dose measurement in space experiments; irradiation through the spacesuit during the extravehicular activity; application of physical methods for the astronauts' protection and radiation exposure on the Moon and Mars. For the average "exit" with duration of ~5 hours with undisturbed conditions the astronaut receives a further 0.3-0.5 mSv, which is close to the average dose inside the station. Cosmic radiation on the Moon's surface is severer than, for example, on Mars. The radiation load on the surface of Mars is average

Optical Coherence Tomography Analysis of the Optic Nerve Head and Surrounding Structures in Long-Duration International Space Station Astronauts

After long-duration spaceflight, morphological changes in the optic nerve head (ONH) and surrounding tissues have been reported. To develop methods to quantify ONH and surrounding tissue changes using preflight and postflight optical coherence tomographic scans of the ONH region. Two separate analyses were done on retrospective data, with the first comparing a preflight group with a control group, followed by preflight to postflight analysis. All astronaut data were collected on the same instrument and maintained by the National Aeronautics and Space Administration (NASA) Lifetime Surveillance of Astronaut Health. Control data were all collected at the University of Houston. Participants were 15 astronauts who had previously been on an approximately 6-month long-duration mission and had associated preflight and postflight ONH scans. The control group consisted of 43 individuals with no history of ocular pathology or microgravity exposure. Development of algorithms and data analysis were performed between 2012 and 2015. The optical coherence tomography data were analyzed using custom MATLAB programs (MathWorks) in which the Bruch membrane opening (BMO) was manually delineated and used as a reference for all morphological measures. The retinal pigment epithelium (RPE) position 2 mm from the center of the BMO was used to calculate the BMO height. Global and quadrant total retinal thickness and retinal nerve fiber layer (RNFL) thickness were calculated for elliptical annular regions referenced to the BMO. The standard circumpapillary circular scan was used to quantify RNFL and choroidal thickness. Among 15 astronauts (mean [SD] age at preflight evaluation, 48.7 [4.0] years) in this retrospective study, the BMO was recessed in preflight astronauts compared with healthy controls and deepened after long-duration microgravity exposure (median change, -9.9 μm; 95% CI of difference, -16.3 to 3.7 μm; P = .03). After long-duration missions, there was an increase in total retinal thickness to 1000 μm and RNFL to 500 μm from the BMO. Circumpapillary RNFL thickness increased by a median of 2.9 μm (95% CI of difference, 1.1-4.4 μm; P < .01), and there was no change in choroidal thickness (median change, 9.3 μm; 95% CI of difference, -12.1 to 19.6 μm; P = .66). After long-duration microgravity exposure, there are disc edema-like changes in the morphology of the ONH and surrounding tissue. The methods developed to analyze the ONH and surrounding tissue can be useful for assessing longitudinal changes and countermeasures in astronauts, as well as potentially for terrestrial disc edema causes.

Internal jugular pressure increases during parabolic flight.

One hypothesized contributor to vision changes experienced by >75% of International Space Station astronauts is elevated intracranial pressure (ICP). While no definitive data yet exist, elevated ICP might be secondary to the microgravity‐induced cephalad fluid shift, resulting in venous congestion (overfilling and distension) and inhibition of cerebrospinal and lymphatic fluid drainage from the skull. The objective of this study was to measure internal jugular venous pressure (IJVP) during normo‐ and hypo‐gravity as an index of venous congestion. IJVP was measured noninvasively using compression sonography at rest during end‐expiration in 11 normal, healthy subjects (3 M, 8 F) during normal gravity (1G; supine) and weightlessness (0G; seated) produced by parabolic flight. IJVP also was measured in two subjects during parabolas approximating Lunar (1/6G) and Martian gravity (1/3G). Finally, IJVP was measured during increased intrathoracic pressure produced using controlled Valsalva maneuvers. IJVP was higher in 0G than 1G (23.9 ± 5.6 vs. 9.9 ± 5.1 mmHg, mean ± SD P < 0.001) in all subjects, and IJVP increased as gravity levels decreased in two subjects. Finally, IJVP was greater in 0G than 1G at all expiration pressures (P < 0.01). Taken together, these data suggest that IJVP is elevated during acute exposure to reduced gravity and may be elevated further by conditions that increase intrathoracic pressure, a strong modulator of central venous pressure and IJVP. However, whether elevated IJVP, and perhaps consequent venous congestion, observed during acute microgravity exposure contribute to vision changes during long‐duration spaceflight is yet to be determined.

Effects of a Closed Space Environment on Gene Expression in Hair Follicles of Astronauts in the International Space Station.

Adaptation to the space environment can sometimes pose physiological problems to International Space Station (ISS) astronauts after their return to earth. Therefore, it is important to develop healthcare technologies for astronauts. In this study, we examined the feasibility of using hair follicles, a readily obtained sample, to assess gene expression changes in response to spaceflight adaptation. In order to investigate the gene expression changes in human hair follicles during spaceflight, hair follicles of 10 astronauts were analyzed by microarray and real time qPCR analyses. We found that spaceflight alters human hair follicle gene expression. The degree of changes in gene expression was found to vary among individuals. In some astronauts, genes related to hair growth such as FGF18, ANGPTL7 and COMP were upregulated during flight, suggesting that spaceflight inhibits cell proliferation in hair follicles.

Evaluating Bone Loss in ISS Astronauts.

The measurement of bone mineral density (BMD) by dual-energy X-ray absorptiometry (DXA) is the Medical Assessment Test used at the NASA Johnson Space Center to evaluate whether prolonged exposure to spaceflight increases the risk for premature osteoporosis in International Space Station (ISS) astronauts. The DXA scans of crewmembers' BMD during the first decade of the ISS existence showed precipitous declines in BMD for the hip and spine after the typical 6-mo missions. However, a concern exists that skeletal integrity cannot be sufficiently assessed solely by DXA measurement of BMD. Consequently, use of relatively new research technologies is being proposed to NASA for risk surveillance and to enhance long-term management of skeletal health in long-duration astronauts. Sibonga JD, Spector ER, Johnston SL, Tarver WJ. Evaluating bone loss in ISS astronauts.

Portland: A Food Biography by Heather Arndt Anderson

 OHQ vol. 116, no. 3 and who is himself forgotten but for Nisbet’s thoughtful portrait, while the Tribes are still here. He tells of the Kalispel elder Victor and his son Masselow, who argued forcefully, in vain, for a reservation in their Pend Oreille Valley homeland. As in his 1994 book, Sources of the River, Nisbet interweaves historical accounts with his own closely observed experiences, moving back and forth through time on the same piece of ground. Sources of the River tethers its digressions to a strong narrative thread: the life of the explorer and fur trader David Thompson. The essays in Ancient Places, by contrast, are multi-threaded, and the tethers are sometimes a little loose. I found the first chapter a tough introduction — readers start with David Thompson’s hunting trip in 1792 and encounter,in rapid succession,the meteor, will-o’-the-wisps, the aurora borealis, and an International Space Station astronaut. I found myself wondering, “Where are we going here, and why?” In other places I would miss a spatial or temporal shift and feel momentarily unmoored. Yet as the essays unfolded, I came to trust Nisbet’s voice, friendly and knowledgeable and always showing me something interesting : an ice cave near downtown Spokane, an 1872 earthquake that dammed the Columbia for a time, a meteorite that became a scientific and popular sensation. His writing is always engaging and sometimes earthily beautiful, as when he is describing a dolomite quarry, or a solitary skate on rough ice. Reading Ancient Places is like hiking with a guide who knows the land like the back of his hand and who can tell you a hundred stories about it, and does, pausing only occasionally to ask himself, “Now, where was I . . . ?” The book will appeal to anyone interested in Northwest history and anyone who loves good, true stories. Gail Wells Corvallis, Oregon PORTLAND: A FOOD BIOGRAPHY by Heather Arndt Anderson Rowman and Littlefield, Lanham, Boulder, New York, and London, 2015. Notes, bibliography, index. 326 pages. $38.00 cloth. With its brimming farmers markets, sumptuous restaurants, eclectic food carts, and locovore markets, Oregon’s Rose City has the reputation as a foodie mecca. In her book, Portland:A Food Biography,author and fourthgeneration Portlander Heather Arndt Anderson sets out to explore the history of Portland’s rich culinary identity. Anderson sets the stage by describing the ingredient-rich landscape at the confluence of the Columbia and Willamette rivers, a place where Chinook and Kalapuya people found salmon, lamprey, wapato, waterfowl, fungi, berries, and more. The indigenous culinary traditions of potlatch feasts derived from this remarkable local abundance. The book proceeds chronologically and topically asAnderson recounts how each group of newcomers added its own food traditions to the mix — starting with pioneering farmers and lumberjacks,and then covering immigrant groups, including Germans, Jews, Chinese, Japanese, Mexicans, and eventually Southeast Asians — each adapting their own skills and recipes to the local scene. For example, earlytwentieth -century Jewish immigrants were making“pink gefilte fish,”using salmon rather than traditional whitefish (p. 253). Anderson then recounts the establishment of Portland’sfoodinfrastructureandbusinesses, describing the locations of old farm districts, ethnicenclaves,historicmarkets,andrenowned restaurants, and how these changed over time. Celebrity Chef James Beard, a Portland native who learned cooking skills from both his mom and a Chinese chef, makes several appearances. Thereisalsoachapterabouthistoriccookbooks that includes a handful of quintessential Portland recipes,including“Lumber Camp Dough-  OHQ vol. 116, no. 3 nuts”and“Huckleberry Breakfast Cake,”giving readers direct access to some of the primary materials that Anderson tapped and providing aspiring cooks with some culinary inspiration. The book is filled with tidbits that foodies will relish. For example, did you know that Portland has both the oldest tofu company and also the oldest craft brewing supply store in the United States? Or that The Web-Foot Cookbook, the Northwest’s first, was created by Portland’s First Presbyterian Church ladies? Or that a large, open-air market once perched right beside the river, downtown? The biggest challenge of writing food history is that sources are spotty and ephemeral: random accounts of travelers, old newspaper ads,memoirs,cookbooks,and trade literature. Anderson makes a significant contribution...

Volume 85A, Number 4, April 2014 Cover Image

On the cover: The artist's imagination places Microflow1, a new portable and robust sheathless microflow cytometer, right in the midst of its new home – Outer Space. The device will be used by the International Space Station astronauts to monitor their own health and for basic research by studying the physiological adaptation of immune system to weightlessness (microgravity). See the accompanying article by Dubeau‐Laramée and colleagues in this issue.Cover design by Bärbel Beran [www.beran‐design.de].

Space station astronauts prepare for spacewalk to make repairs

Space station astronauts prepare for spacewalk to make repairs

Bisphosphonates as a supplement to exercise to protect bone during long-duration spaceflight

We report the results of alendronate ingestion plus exercise in preventing the declines in bone mass and strength and elevated levels of urinary calcium and bone resorption in astronauts during 5.5 months of spaceflight. This investigation was an international collaboration between NASA and the JAXA space agencies to investigate the potential value of antiresorptive agents to mitigate the well-established bone changes associated with long-duration spaceflight. We report the results from seven International Space Station (ISS) astronauts who spent a mean of 5.5 months on the ISS and who took an oral dose of 70 mg of alendronate weekly starting 3 weeks before flight and continuing throughout the mission. All crewmembers had available for exercise a treadmill, cycle ergometer, and a resistance exercise device. Our assessment included densitometry of multiple bone regions using X-ray absorptiometry (DXA) and quantitative computed tomography (QCT) and assays of biomarkers of bone metabolism. In addition to pre- and post-flight measurements, we compared our results to 18 astronauts who flew ISS missions and who exercised using an early model resistance exercise device, called the interim resistance exercise device, and to 11 ISS astronauts who exercised using the newer advanced resistance exercise device (ARED). Our findings indicate that the ARED provided significant attenuation of bone loss compared with the older device although post-flight decreases in the femur neck and hip remained. The combination of the ARED and bisphosphonate attenuated the expected decline in essentially all indices of altered bone physiology during spaceflight including: DXA-determined losses in bone mineral density of the spine, hip, and pelvis, QCT-determined compartmental losses in trabecular and cortical bone mass in the hip, calculated measures of fall and stance computed bone strength of the hip, elevated levels of bone resorption markers, and urinary excretion of calcium. The combination of exercise plus an antiresoptive drug may be useful for protecting bone health during long-duration spaceflight.

Space station astronauts discuss life in space during AGU interview

Just one day after China's Shenzhou‐9 capsule, carrying three Chinese astronauts, docked with the Tiangong‐1 space lab on 18 June, Donald Pettit, a NASA astronaut on the International Space Station (ISS), said it is “a step in the right direction” that more people are in space. “Before they launched, there were six people in space,” he said, referring to those on ISS, “and there are 7 billion people on Earth.” The astronauts were “like one in a billion. Now there are nine people in space,” Pettit said during a 19 June interview that he and two other astronauts onboard ISS had with AGU. Pettit continued, “So the gradient of human beings going into space is moving in the right direction. We need to change these numbers so that more and more human beings can call space their home so we can expand off of planet Earth and move out into our solar system.”

Cardiopulmonary Resuscitation During Spaceflight: Examining the Role of Timing Devices

The majority of International Space Station (ISS) astronauts represent nonmedical professions. In order to serve as Crew Medical Officers (CMO), future crewmembers receive 40-70 h of medical training within 18 mo before missions, including cardiopulmonary resuscitation (CPR) per the Guidelines of the American Heart Association. CPR compliance with the Guidelines is known to vary even among trained clinicians, let alone minimally trained caregivers (e.g., bystanders, nonphysician astronauts). The purpose of this study was to evaluate the effect of timing devices, including audible metronomic tones, on CPR performed by nonmedical personnel, specifically 40 astronaut analogues trained in a fashion and within a timeframe similar to an ISS astronaut. Twenty bystander pairs performed two-person CPR for 4 min on a simulated cardiac arrest patient using three interventions: 1) CPR with no timing devices; 2) CPR with metronomic tones for chest compressions; and 3) CPR with a timing device and metronome for coordinating ventilation and compression rates, respectively. Each CPR performance was evaluated for compliance with the (then current) 2000 AHA Guidelines. Numbers of breaths and compressions significantly deviated from target values in the first two interventions (38 and 42 breaths vs. target of 32 breaths; 282 and 318 compressions vs. target of 240 compressions); the use of timing devices for both components of CPR resulted in significant improvement (32 breaths and 231 compressions). CPR timing devices that coordinate both breaths and compressions improve compliance of astronaut analogue rescuers with CPR guidelines, and may improve overall CPR performance and outcome.

Space station astronauts to make second repair attempt

Space station astronauts to make second repair attempt

Physical and Biological Organ Dosimetry Analysis for International Space Station Astronauts

In this study, we analyzed the biological and physical organ dose equivalents for International Space Station (ISS) astronauts. Individual physical dosimetry is difficult in space due to the complexity of the space radiation environment, which consists of protons, heavy ions and secondary neutrons, and the modification of these radiation types in tissue as well as limitations in dosimeter devices that can be worn for several months in outer space. Astronauts returning from missions to the ISS undergo biodosimetry assessment of chromosomal damage in lymphocyte cells using the multicolor fluorescence in situ hybridization (FISH) technique. Individual-based pre-flight dose responses for lymphocyte exposure in vitro to gamma rays were compared to those exposed to space radiation in vivo to determine an equivalent biological dose. We compared the ISS biodosimetry results, NASA's space radiation transport models of organ dose equivalents, and results from ISS and space shuttle phantom torso experiments. Physical and biological doses for 19 ISS astronauts yielded average effective doses and individual or population-based biological doses for the approximately 6-month missions of 72 mSv and 85 or 81 mGy-Eq, respectively. Analyses showed that 80% or more of organ dose equivalents on the ISS are from galactic cosmic rays and only a small contribution is from trapped protons and that GCR doses were decreased by the high level of solar activity in recent years. Comparisons of models to data showed that space radiation effective doses can be predicted to within about a +/-10% accuracy by space radiation transport models. Finally, effective dose estimates for all previous NASA missions are summarized.

The Sun's Churning Innards Foretell More Solar Storms

Researchers at the National Center for Atmospheric Research predict that the next peak in sunspots will be far bigger than the last peak. The accompanying solar storms could play havoc with satellite communications and threaten space station astronauts. (Read more.)