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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Numerical Investigation of Boiling in a Sealed Tank in Microgravity

Hylton, Sonya Lynn January 2014 (has links)
No description available.
92

Growth and Extinction Limits: Ground Based Testing of Solid Fuel Combustion in Low Stretch Conditions in Support of Space Flight Experiments

Johnston, Michael C. 02 February 2018 (has links)
No description available.
93

Dynamic Control for a Pneumatic Muscle Actuator to Achieve Isokinetic Muscle Strengthening

Hall, Kara Lynn 10 June 2011 (has links)
No description available.
94

MICROGRAVITY DROPLET COMBUSTION IN CARBON DIOXIDE ENRICHED ENVIRONMENTS

Hicks, Michael C. 31 May 2016 (has links)
No description available.
95

INVESTIGATION OF PASSIVE CYCLONIC GAS-LIQUID SEPARATOR PERFORMANCE FOR MICROGRAVITY APPLICATIONS

Kang, Ming-Fang 08 February 2017 (has links)
No description available.
96

Determining the ability of terrestrial time-lapse microgravity surveying on a glacier to find summer mass balance using gravitational modeling

Young, Emma Victoria January 2017 (has links)
Mass loss of alpine glaciers presently account for about half of the cryospheric contribution to the global sea-level rise. Mass balance of alpine glaciers has predominantly been monitored by; (1) glaciological and hydrological methods, and (2) satellite gravimetric methods using data from NASA’s Gravity Recovery and Climate Experiment (GRACE) satellite mission. However, the former can be logistically costly and have large extrapolation errors: measurements taken at monthly temporal scales are expensive and have a spatial resolution of roughly one kilometer. The latter provides monthly mass-balance estimates of aggregates of alpine glaciers, although the spatial resolution (~300 km) is far too coarse for assessing individual glaciers’ mass balance. Ground-based, time-lapse microgravity measurements can potentially overcome some of the disadvantages of the glaciological, hydrological, and satellite gravitational methods for assessing mass changes and their spatial distribution on a single glacier. Gravity models were utilized to predict the gravity signals of the summer-time mass balance, changes in the seasonal snow cover outside of the glacier, and the vertical gravity gradient (VGG) needed for the free-air correction on Wolverine Glacier, AK. The modeled gravity signal of the summer-time mass balance (average of -0.237 mGal) is more than an order of magnitude larger than the uncertainty of conventional relative gravimeters (±0.007 mGal). Therefore, modeling predict that the time-lapse gravitational method could detect the summer-time mass balance on Wolverine Glacier. The seasonal snow effect was shown to have the greatest influence (~ -0.15 mGal) on the outer 100 m boundary of the glacier and minimal effect (~ -0.02 mGal) towards the center, both larger than the uncertainty of relative gravimeters. The VGG has a positive deviation, about -0.1 to -0.2 mGal/m, from the normal VGG (-0.309 mGal/m). Thus, seasonal snow effect and VGG need to be correctly accounted for when processing gravity measurements to derive the residual gravity signal of the glacier mass balance. Accurate measurements of elevation changes, seasonal snow depth, and the VGG should be performed in future gravity surveys of glaciers. / Geology
97

Astrofarmaci: Hur antibiotika fungerar i rymden : En scoping review av antibiotikas farmakokinetiska förändringar i rymden. / Astropharmacy: How antibiotics function in space : A scoping review of the pharmacokinetic changes of antibiotics in space

Qanbari, Nadia January 2024 (has links)
Introduction: Space exploration has been a dream of mankind since ancient times, this dream became a reality with the launch of Sputnik in 1957. Since then, significant advances in space technology have enabled humans to travel beyond the Earth's atmosphere. Although some of the health risks are well known, the effect of changes in the pharmacokinetics of drugs and their effectiveness is not yet fully understood. Aim and Method: This study aims to investigate the effect of space travel on the pharmacokinetics of antibiotics. A scoping review method was employed to investigate the changes in the pharmacokinetics of antibiotics during space travel. A search of the PubMed database was performed using the relevant terms. Inclusion criteria included available English full-text articles. A three-step selection process was employed, followed by data analysis and evaluation, to select relevant original scientific articles. Results: The findings suggest that the pharmacokinetics of some antibiotics, such as ciprofloxacin penicillin and benzylpenicillin, may not be significantly altered in microgravity environments. Further research is needed to better understand the implications of space travel on antibiotic efficacy and safety. Conclusion: Current research on the pharmacokinetic changes of antibiotics in microgravity simulations shows little change compared to Earth. However, further research is crucial to understand their bioavailability, durability, and performance in space environments, ensuring the health and safety of space travelers.
98

Spaceflight Induces Strength Decline in Caenorhabditis elegans

22 November 2023 (has links)
Yes / Background: Understanding and countering the well-established negative health consequences of spaceflight remains a primary challenge preventing safe deep space exploration. Targeted/personalized therapeutics are at the forefront of space medicine strategies, and cross-species molecular signatures now define the 'typical' spaceflight response. However, a lack of direct genotype-phenotype associations currently limits the robustness and, therefore, the therapeutic utility of putative mechanisms underpinning pathological changes in flight. Methods: We employed the worm Caenorhabditis elegans as a validated model of space biology, combined with 'NemaFlex-S' microfluidic devices for assessing animal strength production as one of the most reproducible physiological responses to spaceflight. Wild-type and dys-1 (BZ33) strains (a Duchenne muscular dystrophy (DMD) model for comparing predisposed muscle weak animals) were cultured on the International Space Station in chemically defined media before loading second-generation gravid adults into NemaFlex-S devices to assess individual animal strength. These same cultures were then frozen on orbit before returning to Earth for next-generation sequencing transcriptomic analysis. Results: Neuromuscular strength was lower in flight versus ground controls (16.6% decline, p
99

Numerical modeling of flame spread over spherical solid fuel under low speed flow in microgravity:Model development and comparison to space flight experiments

Endo, Makoto 31 May 2016 (has links)
No description available.
100

Alterations in Human Baroreceptor Reflex Regulation of Blood Pressure Following 15 Days of Simulated Microgravity Exposure

Crandall, Craig G. (Craig Gerald) 08 1900 (has links)
Prolonged exposure to microgravity is known to invoke physiological changes which predispose individuals to orthostatic intolerance upon readaptation to the earth's gravitational field. Attenuated baroreflex responsiveness has been implicated in contributing to this inability to withstand orthostatic stress. To test this hypothesis, eight individuals were exposed to 15 days of simulated microgravity exposure using the 6° head-down bed rest model. Prior to, and after the simulated microgravity exposure, the following were assessed: a) aortic baroreflex function; b) carotid baroreflex function; c) cardiopulmonary baroreflex function; and d) the degree of interaction between the cardiopulmonary and carotid baroreflexes.

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