The Virtual Spaceplane: Integrating Multiple Motion Models and Hypertext in a Virtual Environment

The Air Force is currently investigating the possibility of developing a manned vehicle capable of operating in space. This Military Spaceplane (MSP) will be capable of ascent to low-earth orbit and maneuvering while in orbit. The goal of this research involved creating the Virtual Spaceplane (VSP), a virtual environment (VE) simulator for the MSP. This thesis examines two ideas significant to virtual environments and cockpit design: multiple motion models and hypertext in a VE. Movement in a VE has traditionally been modeled using a single motion model. Little work has been done to allow a change of the motion model used during the simulation. This thesis suggests partitioning simulation entities into two sections: the geometry model and the propagation model. This approach is demonstrated in the VSP using multiple propagation models as it transitions from runway to orbit. This thesis also examines the use of hypertext within a VE. Hypertext has been shown useful for readers to quickly locate information. This thesis will discuss the integration of a hypertext interface into the VSP. The hypertext interface provides checklists, systems status, and consumables status. Hypertext provides the spaceplane pilot with an effective means of referencing large amounts of data

Conformational Entropy in PEPCK Catalysis: Dynamic Motions Critical to Function

Enzymes increase the rate at which chemical reactions occur. How they achieve this rate increase has been an area of intense research for many years. Multiple studies have shown that dynamic motions of individual protein segments can play a role in enzyme function. Our enzyme of interest, phosphoenolpyruvate carboxykinase (PEPCK), has multiple dynamic motions that work in concert during the catalytic cycle. One of these mobile elements, termed the omega-loop due to its architecture, acts like a lid that closes over the active site and has been hypothesized to serve multiple functions during the catalytic cycle. Furthermore, the act of opening and closing the lid domain is thought to be a delicate free energy balance, meaning the lid pays an energetic penalty to close, which is offset by the energetic contribution from substrate binding. To investigate the role of the loop, specifically the open/closed transition, and to probe for unappreciated roles, multiple mutant enzymes were created. In the first set of mutations the lid region was removed to investigate other potential roles for the omega-loop. In the second set two different amino acid residues (Ala-467 and Glu-89) were mutated to either increase the energetic penalty of lid closure or decrease the energetic contribution from substrate binding. The resultant mutants were characterized via structure/function experiments. The data revealed two new roles for the omega-loop lid, confirmed the delicate free energy balance, and shed light on the energetic pathway between the active site and the lid. Taking into account the data from the WT and all seven mutant PEPCK enzymes, a revised model for the role of the omega-loop lid during catalysis is proposed: The role of the lid during the catalytic cycle is to correctly position the substrates in the active site, stabilize the R-loop and N/C-terminal lobe closure, and sequester and protect the reaction intermediate

Dark Matter Searches with Astroparticle Data

The existence of dark matter (DM) was first noticed by Zwicky in the 1930s, but its nature remains one of the great unsolved problems of physics. A variety of observations indicate that it is non-baryonic and non-relativistic. One of the preferred candidates for non-baryonic DM is a weakly interacting massive particle (WIMP) that in most models is stable. WIMP self-annihilation can produce cosmic rays, gamma rays, and other particles with signatures that may be detectable. Hints of anomalous cosmic-ray spectra found by recent experiments, such as PAMELA, have motivated interesting interpretations in terms of DM annihilation and/or decay. However, these signatures also have standard astrophysical interpretations, so additional evidence is needed in order to make a case for detection of DM annihilation or decay. Searches by the Fermi Large Area Telescope for gamma-ray signals from clumps, nearby dwarf spheroidal galaxies, and galaxy clusters have also been performed, along with measurements of the diffuse Galactic and extragalactic gamma-ray emission. In addition, imaging atmospheric Cherenkov telescopes like HESS, MAGIC, and VERITAS have reported on searches for gamma-ray emission from dwarf galaxies. In this review, we examine the status of searches for particle DM by these instruments and discuss the interpretations and resulting DM limits.Comment: Solicited review article to appear in Annual Reviews of Astronomy and Astrophysics. 52 pages, 10 figures (higher resolution figures will appear in the journal article

Determining the Growth Rate of Various Escherichia coli Cell Lines in Different Broths

https://openworks.mdanderson.org/sumexp22/1077/thumbnail.jp

Persons Who May Be Alaska Mental Health Trust Beneficiaries were more likely to experience Intimate Partner Violence and Sexual Violence

The Alaska Justice Information Center (AJiC) at the University of Alaska Anchorage has released this Fact Sheet in conjunction with a new report, “Adverse Childhood Experiences, Intimate Partner Violence, and Sexual Violence Among Persons Who May Be Alaska Mental Health Trust Beneficiaries: Findings from the Alaska Victimization Survey.” This report used data from the 2020 Alaska Victimization Survey (AVS) to estimate the extent to which victims of intimate partner violence and sexual assault were Alaska Mental Health Trust beneficiaries. It also estimated the extent to which Alaska Mental Health Trust beneficiaries experienced Adverse Childhood Experiences (ACEs). Alaska Mental Health Trust beneficiaries include Alaskans with mental illness, developmental disabilities, chronic alcohol or drug addiction, Alzheimer’s disease and related dementia, and traumatic brain injuries

Persons Who May Be Alaska Mental Health Trust Beneficiaries had more Adverse Childhood Experiences

The Alaska Justice Information Center (AJiC) at the University of Alaska Anchorage has released this Fact Sheet in support of the report, “Adverse Childhood Experiences, Intimate Partner Violence, and Sexual Violence Among Persons Who May Be Alaska Mental Health Trust Beneficiaries: Findings from the Alaska Victimization Survey.” This report used data from the 2020 Alaska Victimization Survey (AVS) to estimate the extent to which victims of intimate partner violence and sexual assault were Alaska Mental Health Trust beneficiaries. It also estimated the extent to which Alaska Mental Health Trust beneficiaries experienced Adverse Childhood Experiences (ACEs). Alaska Mental Health Trust beneficiaries include Alaskans with mental illness, developmental disabilities, chronic alcohol or drug addiction, Alzheimer’s disease and related dementia, and traumatic brain injuries

Method for Estimating Thread Strength Reduction of Damaged Parent Holes with Inserts

During normal assembly and disassembly of bolted-joint components, thread damage and/or deformation may occur. If threads are overloaded, thread damage/deformation can also be anticipated. Typical inspection techniques (e.g. using GO-NO GO gages) may not provide adequate visibility of the extent of thread damage. More detailed inspection techniques have provided actual pitch-diameter profiles of damaged-hardware holes. A method to predict the reduction in thread shear-out capacity of damaged threaded holes has been developed. This method was based on testing and analytical modeling. Test samples were machined to simulate damaged holes in the hardware of interest. Test samples containing pristine parent-holes were also manufactured from the same bar-stock material to provide baseline results for comparison purposes. After the particular parent-hole thread profile was machined into each sample a helical insert was installed into the threaded hole. These samples were tested in a specially designed fixture to determine the maximum load required to shear out the parent threads. It was determined from the pristine-hole samples that, for the specific material tested, each individual thread could resist an average load of 3980 pounds. The shear-out loads of the holes having modified pitch diameters were compared to the ultimate loads of the specimens with pristine holes. An equivalent number of missing helical coil threads was then determined based on the ratio of shear-out loads for each thread configuration. These data were compared with the results from a finite element model (FEM). The model gave insights into the ability of the thread loads to redistribute for both pristine and simulated damage configurations. In this case, it was determined that the overall potential reduction in thread load-carrying capability in the hardware of interest was equal to having up to three fewer threads in the hole that bolt threads could engage. One- half of this potential reduction was due to local pitch-diameter variations and the other half was due to overall pitch-diameter enlargement beyond Class 2 fit. This result was important in that the thread shear capacity for this particular hardware design was the limiting structural capability. The details of the method development, including the supporting testing, data reduction and analytical model results comparison will be discussed hereafter

EC93-129 Buying and Selling Alfalfa Hay

Alfalfa hay is an important agricultural product. Although often fed on the farms where it is produced, much alfalfa hay is also sold as a cash crop. It often constitutes a major source of income for those who sell it, or a major expense for those who buy it. Such transactions involve billions of dollars nationwide each year. This extension circular discusses the seller\u27s and buyer\u27s perspective on buying and selling alfalfa hay