607 research outputs found
Microprocessor-Based Systems Control for the Rigidized Inflatable Get-Away-Special Experiment
As the demand for space based communications and faster data throughput increase, satellites are becoming larger. Larger satellite antennas help to provide the needed gain to increase communications in space. Compounding the performance and size trade-offs are the payload weight and size limit imposed by the launch vehicles. Inflatable structures offer a cost saving opportunity since the structure is significantly lighter and has a reduced storage volume. This allows for smaller launch vehicles and for increased performance capabilities. Inflatable structures offer possibilities for increased satellite lifetimes, increased communications capacity, and reduce launch costs. This thesis develops and implements the computer control system and power system to support the Rigidized Inflatable Get-Away-Experiment. The autonomous computer system controls the flow of the experiment while at the same time collecting and recording temperature, pressure, vibration, and image data. The computer system consists of two processors, one for experiment control and sensor data collection and the second for image data collection. These two systems can work simultaneously to control the flow of the experiment and meet the experiment objectives. Examples of the data collection include heating curves, pressure, tube transfer function plots and images. This thesis also develops the Matlab® tools required to analyze the data collected by the computers for post-flight data processing. This thesis lays the groundwork for a microprocessor-based architecture for autonomous space experiments. This pioneering effort has been selected for flight testing on-board the U.S. Space Shuttle
Star Formation and Clumps in Cosmological Galaxy Simulations with Radiation Pressure Feedback
Cosmological simulations of galaxies have typically produced too many stars
at early times. We study the global and morphological effects of radiation
pressure (RP) in eight pairs of high-resolution cosmological galaxy formation
simulations. We find that the additional feedback suppresses star formation
globally by a factor of ~2. Despite this reduction, the simulations still
overproduce stars by a factor of ~2 with respect to the predictions provided by
abundance matching methods for halos more massive than 5E11 Msun/h (Behroozi,
Wechsler & Conroy 2013).
We also study the morphological impact of radiation pressure on our
simulations. In simulations with RP the average number of low mass clumps falls
dramatically. Only clumps with stellar masses Mclump/Mdisk <= 5% are impacted
by the inclusion of RP, and RP and no-RP clump counts above this range are
comparable. The inclusion of RP depresses the contrast ratios of clumps by
factors of a few for clump masses less than 5% of the disk masses. For more
massive clumps, the differences between and RP and no-RP simulations diminish.
We note however, that the simulations analyzed have disk stellar masses below
about 2E10 Msun/h.
By creating mock Hubble Space Telescope observations we find that the number
of clumps is slightly reduced in simulations with RP. However, since massive
clumps survive the inclusion of RP and are found in our mock observations, we
do not find a disagreement between simulations of our clumpy galaxies and
observations of clumpy galaxies. We demonstrate that clumps found in any single
gas, stellar, or mock observation image are not necessarily clumps found in
another map, and that there are few clumps common to multiple maps.Comment: 13 pages, 6 figures, submitted to MNRA
Population Pharmacokinetic and Pharmacodynamic Analysis of Buprenorphine for the Treatment of Neonatal Abstinence Syndrome
Neonatal abstinence syndrome (NAS) is a condition affecting newborns exposed to an opioid in utero. Symptoms of NAS include excessive crying, poor feeding, and disordered autonomic control. Up to 2/3 of infants will require pharmacologic therapies to reach symptom control. Opioids including morphine and methadone are the current first-line treatments. Buprenorphine is being investigated as a treatment of NAS. The purpose of this analysis was to evaluate the pharmacokinetics (PK) and pharmacodynamics (PD) of BUP in infants with NAS.
Poster presented at American Society for Clinical Pharmacology and Therapeutics (ASCPT) 2017 Annual Meeting, March 15-18, 2017 in Washington DC.https://jdc.jefferson.edu/petposters/1004/thumbnail.jp
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