4,764 research outputs found
ECLSS ORION GFAST
Pathway Student Showcase - Environmental Control and Life Support System for Orion Ground and Flight Application Software Tea
Environmental Control System Development
With the ever-growing desire for mankind to reach destinations whose distances had been deemed impossible to transit, the largest rocket known to man was designed and is being developed. The Space Launch System (SLS), National Aeronautics and Space Administrations (NASA) solution for deep space travel, will begin its missions with the launch of Exploration Mission 1 (EM-1) and Exploration Mission 2 (EM-2). In order to accommodate the larger rocket, Kennedy Space Center made crucial upgrades to its existing facilities. At Launch Complex 39B, an entirely new Environmental Control System (ECS) was developed to supply the vehicle with the appropriate air or nitrogen gas mixture for launch. The new ECS displays must undergo Validation and Verification (V&V) using testing procedures developed to meet this requirement
Syncretic Immersion: Tolkien’s Languages As History, Artifacts, And Meta-Narratives
J.R.R. Tolkien’s Middle-earth has been dissected and researched by philologists, medievalists, and literary theorists for decades. Though his work with languages (both historical and invented) has garnered attention over the past few decades, few scholars have looked at his languages in terms of their rhetorical functions within the narrative (as history), with the narrative (as artifacts), and without (as cultural participation). Mark Wolf’s theories on immersion is applied to Tolkien’s legendarium and illuminates his works as uniquely fixated in several modes of immersion at once. Narrative immersion is utilized to understand Tolkien’s works as a furthering of cultural values, languages, and traditions. As these elements of narrative are explored, Tolkien’s legendarium can be seen through conceptual, perceptual, and physical lenses, culminating into a syncretically immersive experience
Deinococcus radiodurans RNA ligase exemplifies a novel ligase clade with a distinctive N-terminal module that is important for 5′-PO(4) nick sealing and ligase adenylylation but dispensable for phosphodiester formation at an adenylylated nick
Deinococcus radiodurans RNA ligase (DraRnl) is a template-directed ligase that seals nicked duplexes in which the 3′-OH strand is RNA. DraRnl is a 342 amino acid polypeptide composed of a C-terminal adenylyltransferase domain fused to a distinctive 126 amino acid N-terminal module (a putative OB-fold). An alanine scan of the C domain identified 9 amino acids essential for nick ligation, which are located within nucleotidyltransferase motifs I, Ia, III, IIIa, IV and V. Seven mutants were dysfunctional by virtue of defects in ligase adenylylation: T163A, H167A, G168A, K186A, E230A, F281A and E305A. Four of these were also defective in phosphodiester formation at a preadenylylated nick: G168A, E230A, F281A and E305A. Two nick sealing-defective mutants were active in ligase adenylylation and sealing a preadenylylated nick, thereby implicating Ser185 and Lys326 in transfer of AMP from the enzyme to the nick 5′-PO(4). Whereas deletion of the N-terminal domain suppressed overall nick ligation and ligase adenylylation, it did not compromise sealing at a preadenylylated nick. Mutational analysis of 15 residues of the N domain identified Lys26, Gln31 and Arg79 as key constituents. Structure–activity relationships at the essential residues were determined via conservative substitutions. We propose that DraRnl typifies a new clade of polynucleotide ligases. DraRnl homologs are detected in several eukaryal proteomes
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Hydrologic Data for Urban Studies in The Austin, Texas, Metropolitan Area, 1982
The technical report mentions Waller Creek as a main stream in the study area, but a preliminary search provides no results to specific data from the site.Hydrologic investigations of urban watersheds in Texas were begun by the U.S. Geological Survey in 1954. Studies are now in progress in Austin, and Houston. Studies have been completed in the Dallas, Fort Worth, and San Antonio areas.
The Geological Survey, in cooperation with the Texas Department of Water Resources, began hydrologic studies in the Austin urban area in 1954. In cooperation with the city of Austin, the program was expanded in 1975 to include additional streamflow and rainfall gaging stations, and the collection of surface water-quality data. In 1978, the program was expanded to include a ground-water resources study of the South Austin metropolitan area in the Balcones Fault Zone.Waller Creek Working Grou
Collisional Stripping and Disruption of Super-Earths
The final stage of planet formation is dominated by collisions between
planetary embryos. The dynamics of this stage determine the orbital
configuration and the mass and composition of planets in the system. In the
solar system, late giant impacts have been proposed for Mercury, Earth, Mars,
and Pluto. In the case of Mercury, this giant impact may have significantly
altered the bulk composition of the planet. Here we present the results of
smoothed particle hydrodynamics simulations of high-velocity (up to ~5 v_esc)
collisions between 1 and 10 M_Earth planets of initially terrestrial
composition to investigate the end stages of formation of extrasolar
super-Earths. As found in previous simulations of collisions between smaller
bodies, when collision energies exceed simple merging, giant impacts are
divided into two regimes: (1) disruption and (2) hit-and-run (a grazing
inelastic collision and projectile escape). Disruption occurs when the impact
parameter is near zero, when the projectile mass is small compared to the
target, or at extremely high velocities. In the disruption regime, we derive
the criteria for catastrophic disruption (when half the total colliding mass is
lost), the transition energy between accretion and erosion, and a scaling law
for the change in bulk composition (iron-to-silicate ratio) resulting from
collisional stripping of a mantle.Comment: 10 pages, 1 table, 4 figures. Accepted for publication in ApJ Letter
Artificial scaling laws of the dynamical magnetic susceptibility in heavy-fermion systems
We report here how artificial, thus erroneous, scaling laws of the dynamical
magnetic susceptibility can be obtained when data are not treated carefully. We
consider the example of the heavy-fermion system
CeLaRuSi and we explain how different kinds of
artificial scaling laws in can be plotted in a low temperature
regime where the dynamical susceptibility is nearly temperature independent.Comment: 4 pages, 4 figure
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