Severity: Warning
Message: fopen(/var/lib/php/sessions/ci_session1bdbfhl9jj167tcqlveeu47e2nnrgb3m): Failed to open stream: No space left on device
Filename: drivers/Session_files_driver.php
Line Number: 177
Backtrace:
File: /var/www/html/index.php
Line: 316
Function: require_once
Severity: Warning
Message: session_start(): Failed to read session data: user (path: /var/lib/php/sessions)
Filename: Session/Session.php
Line Number: 137
Backtrace:
File: /var/www/html/index.php
Line: 316
Function: require_once
134 results match your criteria: "Lyndon B. Johnson Space Center[Affiliation]"
Sci Adv
December 2024
McCaig Institute for Bone and Joint Health, University of Calgary, 3280 Hospital Drive NW, Calgary T2N 4Z6, Canada.
Mechanical unloading causes bone loss, but it remains unclear whether disuse-induced changes to bone microstructure are permanent or can be recovered upon reloading. We examined bone loss and recovery in 17 astronauts using time-lapsed high-resolution peripheral quantitative computed tomography and biochemical markers to determine whether disuse-induced changes are permanent. During 6 months in microgravity, resorption was threefold higher than formation.
View Article and Find Full Text PDFCommun Med (Lond)
June 2024
NASA Langley Research Center, Hampton, VA, USA.
Background: Expanding human presence in space through long-duration exploration missions and commercial space operations warrants improvements in approaches for quantifying crew space radiation health risks. Currently, risk assessment models for radiogenic cancer and cardiovascular disease consider age, sex, and tobacco use, but do not incorporate other modifiable (e.g.
View Article and Find Full Text PDFLife Sci Space Res (Amst)
August 2023
Alan Levin Department of Mechanical and Nuclear Engineering, Kansas State University, Manhattan, KS, United States of America. Electronic address:
In the last decade, NASA and other space exploration organizations have focused on making crewed missions to different locations in our solar system a priority. To ensure the crew members' safety in a harsh radiation environment outside the protection of the geomagnetic field and atmosphere, a robust radiation protection system needs to be in place. Passive shielding methods, which use mass shielding, are insufficient as a standalone means of radiation protection for long-term deep-space missions.
View Article and Find Full Text PDFNutr Bull
June 2023
Institute of Nutrition and Food Sciences, Nutritional Physiology, University of Bonn, Bonn, Germany.
Dietary countermeasures to mitigate detrimental spaceflight-induced effects on bone health would alleviate the requirements and the consequences imposed by other types of countermeasures for this risk. We hypothesised that antioxidant supplementation during 60 days of 6° head-down tilt bed rest (HDBR), an analogue of spaceflight, would have a protective effect on bone mineral density (BMD), content (BMC) and bone structure parameters. An exploratory, randomised, controlled, single-blind intervention trial was conducted in a parallel design with 20 healthy male volunteers (age 34 ± 8 y, weight 74 ± 6 kg).
View Article and Find Full Text PDFClin Chem
April 2023
Director of Clinical Laboratories, Space Medicine Division, National Aeronautics and Space Administration, Lyndon B. Johnson Space Center, Houston, TX, United States.
Cells
December 2022
National Aeronautics and Space Administration (NASA) Johnson Space Center, Human Health and Performance Directorate, Houston, TX 77058, USA.
The field of human space travel is in the midst of a dramatic revolution. Upcoming missions are looking to push the boundaries of space travel, with plans to travel for longer distances and durations than ever before. Both the National Aeronautics and Space Administration (NASA) and several commercial space companies (e.
View Article and Find Full Text PDFSci Rep
June 2022
McCaig Institute for Bone and Joint Health, University of Calgary, 3280 Hospital Drive NW, Calgary, AB, T2N 4Z6, Canada.
Determining the extent of bone recovery after prolonged spaceflight is important for understanding risks to astronaut long-term skeletal health. We examined bone strength, density, and microarchitecture in seventeen astronauts (14 males; mean 47 years) using high-resolution peripheral quantitative computed tomography (HR-pQCT; 61 μm). We imaged the tibia and radius before spaceflight, at return to Earth, and after 6- and 12-months recovery and assessed biomarkers of bone turnover and exercise.
View Article and Find Full Text PDFVasc Med
August 2022
Department of Medicine, Division of Hematology, University of North Carolina, Chapel Hill, NC, USA.
Background: Thrombosis of the left internal jugular vein in an astronaut aboard the International Space Station was recently described, incidentally discovered during a research study of blood flow in neck veins in microgravity. Given this event, and the high incidence of flow abnormalities, the National Aeronautics and Space Administration (NASA) instituted an occupational surveillance program to evaluate astronauts for venous thrombosis.
Methods: Duplex ultrasound of the bilateral internal jugular veins was conducted on all NASA astronauts terrestrially, and at three points during spaceflight.
Life (Basel)
January 2022
NASA John F. Kennedy Space Center, Kennedy Space Center, Merritt Island, FL 32899, USA.
One of the major concerns for long-term exploration missions beyond the Earth's magnetosphere is consequences from exposures to solar particle event (SPE) protons and galactic cosmic rays (GCR). For long-term crewed Lunar and Mars explorations, the production of fresh food in space will provide both nutritional supplements and psychological benefits to the astronauts. However, the effects of space radiation on plants and plant propagules have not been sufficiently investigated and characterized.
View Article and Find Full Text PDFBr J Sports Med
February 2022
Department of Radiology, University of Calgary Cumming School of Medicine, Calgary, Alberta, Canada
Objectives: Bone loss remains a primary health concern for astronauts, despite in-flight exercise. We examined changes in bone microarchitecture, density and strength before and after long-duration spaceflight in relation to biochemical markers of bone turnover and exercise.
Methods: Seventeen astronauts had their distal tibiae and radii imaged before and after space missions to the International Space Station using high-resolution peripheral quantitative CT.
NPJ Microgravity
November 2020
NASA Langley Research Center, Hampton, VA, USA.
NASA's plans for space exploration include a return to the Moon to stay-boots back on the lunar surface with an orbital outpost. This station will be a launch point for voyages to destinations further away in our solar system, including journeys to the red planet Mars. To ensure success of these missions, health and performance risks associated with the unique hazards of spaceflight must be adequately controlled.
View Article and Find Full Text PDFJ Appl Physiol (1985)
November 2020
Lyndon B. Johnson Space Center, National Aeronautics and Space Administration, Houston, Texas.
Proc Natl Acad Sci U S A
September 2020
Jacob-Johnson Space Center Engineering, Technology and Science Contract, The Lyndon B. Johnson Space Center, National Aeronautics and Space Administration, Houston, TX 77058.
Lunar mare basalts are depleted in F and Cl by approximately an order of magnitude relative to mid-ocean ridge basalts and contain two Cl-bearing components with elevated isotopic compositions relative to the bulk-Earth value of ∼0‰. The first is a water-soluble chloride constituting 65 ± 10% of total Cl with δCl values averaging 3.0 ± 4.
View Article and Find Full Text PDFFront Physiol
July 2020
Lyndon B. Johnson Space Center, National Aeronautics and Space Administration, Houston, TX, United States.
: Chronic exposure to the weightlessness-induced cephalad fluid shift is hypothesized to be a primary contributor to the development of spaceflight-associated neuro-ocular syndrome (SANS) and may be associated with an increased risk of venous thrombosis in the jugular vein. This study characterized the relationship between gravitational level (G-level) and acute vascular changes. : Internal jugular vein (IJV) cross-sectional area, inferior vena cava (IVC) diameter, and common carotid artery (CCA) flow were measured using ultrasound in nine subjects (5F, 4M) while seated when exposed to 1.
View Article and Find Full Text PDFFront Physiol
July 2020
Lyndon B. Johnson Space Center, National Aeronautics and Space Administration, Houston, TX, United States.
The incidence of presyncopal events is high soon after a long-duration spaceflight;>60% of returning astronauts could not complete a 10-min 80° head-up tilt test on landing day (R+0) after ~6 months of spaceflight. The objective of this study was to demonstrate the ability of a lower body gradient compression garment (GCG) to protect against an excessive increase in heart rate and a decrease in blood pressure during standing after long-duration spaceflight. : Eleven astronauts (9 M, 2 F) volunteered to participate.
View Article and Find Full Text PDFRecently reported studies considering nonlinearity in the effects of low-dose space radiation have assumed a nontargeted mechanism. To date, few analyses have been performed to assess whether a nontargeted term is supported by the available data. The Harderian gland data from Alpen et al.
View Article and Find Full Text PDFBone
August 2020
Division of Biomedical Research and Environmental Sciences, NASA Lyndon B. Johnson Space Center, Houston, TX, USA.
Quantitative computed tomography (QCT) based finite element (FE) models can compute subject-specific proximal femoral strengths, or fracture loads, that are associated with hip fracture risk. These fracture loads are more strongly associated with measured fracture loads than are DXA and QCT measures and are predictive of hip fracture independently of DXA bone mineral density (BMD). However, interpreting FE-computed fracture loads of younger subjects for the purpose of evaluating hip fracture risk in old age is challenging due to limited reference data.
View Article and Find Full Text PDFNPJ Microgravity
June 2019
2Biomedical Research and Environmental Sciences Division, Human Health and Performance Directorate, NASA Lyndon B. Johnson Space Center, Houston, TX 77058 USA.
Acute exposure to carbon dioxide (CO) concentrations below those found on the International Space Station are reported to deteriorate complex decision-making. Effective decision-making is critical to human spaceflight, especially during an emergency response. Therefore, effects of acutely elevated CO on decision-making competency and various cognitive domains were assessed in astronaut-like subjects by the (SMS) and test batteries.
View Article and Find Full Text PDFNPJ Microgravity
March 2019
18Division of Biomedical Research and Environmental Sciences, NASA Lyndon B. Johnson Space Center, Houston, TX USA.
Concerns raised at a 2010 Bone Summit held for National Aeronautics and Space Administration Johnson Space Center led experts in finite element (FE) modeling for hip fracture prediction to propose including hip load capacity in the standards for astronaut skeletal health. The current standards for bone are based upon areal bone mineral density (aBMD) measurements by dual X-ray absorptiometry (DXA) and an adaptation of aBMD cut-points for fragility fractures. Task Group members recommended (i) a minimum permissible outcome limit (POL) for post-mission hip bone load capacity, (ii) use of FE hip load capacity to further screen applicants to astronaut corps, (iii) a minimum pre-flight standard for a second long-duration mission, and (iv) a method for assessing which post-mission physical activities might increase an astronaut's risk for fracture after return.
View Article and Find Full Text PDFmBio
January 2019
Department of Biology and Biochemistry, University of Houston, Houston, Texas, USA
The long-term response of microbial communities to the microgravity environment of space is not yet fully understood. Of special interest is the possibility that members of these communities may acquire antibiotic resistance. In this study, cells were grown under low-shear modeled microgravity (LSMMG) conditions for over 1,000 generations (1000G) using chloramphenicol treatment between cycles to prevent contamination.
View Article and Find Full Text PDFCurr Opin Clin Nutr Metab Care
November 2018
NASA Lyndon B. Johnson Space Center, Houston, Texas, USA.
Purpose Of Review: Within the last decade, it was realized that during and after long-duration spaceflight, some astronauts experience ophthalmic abnormalities including refractive changes, optic disc edema, globe flattening, choroidal folds, and cotton wool spots. Much research has been initiated and conducted, but little evidence is available to differentiate affected crewmembers.
Recent Findings: The first published data to distinguish between affected and nonaffected crewmembers identified biochemical differences in affected astronauts: one-carbon pathway metabolite concentrations were higher in these individuals than in nonaffected astronauts, even before flight.
Sci Rep
May 2018
KBRwyle, Science and Space Operations, Houston, Texas, USA.
Understanding space radiation health effects is critical due to potential increased morbidity and mortality following spaceflight. We evaluated whether there is evidence for excess cardiovascular disease or cancer mortality in early NASA astronauts and if a correlation exists between space radiation exposure and mortality. Astronauts selected from 1959-1969 were included and followed until death or February 2017, with 39 of 73 individuals still alive at that time.
View Article and Find Full Text PDFAm J Clin Nutr
May 2018
Human Health and Performance Directorate, NASA Lyndon B. Johnson Space Center, Houston, TX.
Background: Bed rest studies document that a lower dietary acid load is associated with lower bone resorption.
Objective: We tested the effect of dietary acid load on bone metabolism during spaceflight.
Design: Controlled 4-d diets with a high or low animal protein-to-potassium (APro:K) ratio (High and Low diets, respectively) were given to 17 astronauts before and during spaceflight.
J Elder Abuse Negl
March 2018
a Division of Geriatric and Palliative Medicine; Texas Elder Abuse and Mistreatment (TEAM) Institute; and UTHealth Consortium on Aging , The University of Texas Health Science Center at Houston (UTHealth).
Objectives: Interventions are critical to improving clinical outcomes in elder self-neglecters. This study assessed feasibility of a randomized controlled trial of oral vitamin D in Adult Protective Services-substantiated self-neglect clients ≥65 years.
Methods: Participants were directly observed to consume ergocalciferol 50,000 IU (treatment) or ergocalciferol 400 IU (control), once a month, for 10 months.
Sci Robot
March 2018
NASA Lyndon B. Johnson Space Center, Houston, TX 77058, USA. Email:
NASA's space robots will need the repair capabilities and intelligence of R2D2 and BB-8 but may resemble C3PO and K-2SO.
View Article and Find Full Text PDF