Will the Real Miss Scarlett Please Stand Up: How the Life of Mary Boykin Chesnut Can Be Considered a Model for Margaret Mitchell\u27s Scarlett O\u27Hara

Scarlett O\u27Hara may well be one of the most well known Southern women of all time. Outside of the world of fiction, Mary Boykin Chesnut is probably the most famous woman of the Confederate era. There are striking similarities between both women, not only in terms of their experiences but also their reactions to these experiences, as well as their striking personalities. Because of these similarities, it is quite easy to draw parallels between the two women, and surprisingly, this subject, although it has been suggested, has not been explored in greater detail. Mary DeCredico\u27s introduction to her biography of Mary Boykin Chesnut states, \u27the record of her life could have served as a model for Margaret Mitchell as she created her much-loved heroine. Mary had the charm, intelligence, and independence that Scarlett exhibited again and again.\u27 After e-mail correspondence with DeCredico, I found her statement to be rooted in the remarkable similarities of the women, but no other study comparing these two women exists. My research, especially concerning Margaret Mitchell, has not turned up a definitive answer as to who Mitchell based Scarlett on. The purpose of this thesis is to test the hypothesis that Scarlett O\u27Hara is in fact based on Mary Boykin Chesnut. It is impossible to find a definitive answer to this question, especially considering that while she was still alive, Margaret Mitchell vehemently denied that any of her characters were based on a real person. She describes Scarlett only as a woman who has lived through the destruction of the Southern world she knew and rose from its ashes as a new woman. After Mitchell\u27s death, her husband John burned all her letters. Only theories exist as to who Scarlett is based on. My goal is to extrapolate the theory that Chesnut was used as a model, and give specific examples of their parallel experiences, personalities, and reactions to show that the life and actions of Mary Chesnut and Scarlett O\u27Hara are similar enough to conclude that it is indeed possible that Mitchell used Mary\u27s life to create Scarlett. Although it seems impossible to know where Scarlett came from, I argue that Mary Boykin Chesnut and Scarlett have similar experiences, reactions to those experiences, and similar personalities to warrant further study. Mary Boykin Chesnut\u27s diaries reveal intimate details of her life, her inner thoughts, and her actions. Mitchell\u27s Scarlett acts, thinks, and speaks in hauntingly similar ways. This thesis is a presentation of my findings as to the similarities of the two women, and how they at times conformed, and at times chafed against traditional roles of Southern females. In short, this thesis explores how Mary Boykin Chesnut was used as a model by Margaret Mitchell for Scarlett O\u27Hara in her novel Gone With the Wind

Effects of the Abused Inhalant Toluene on mPFC-Dependent Cognitive Behaviors and Associated Neural Activity

Volatile organic solvents like toluene induce euphoria and intoxication when inhaled at high concentrations. Inhalant misuse is linked to behavioral, cognitive, and anatomical deficits in humans leading to a reduced productivity and quality of life. Yet, preclinical studies on the effect of inhalants on executive control in animal models are limited. We address this gap in knowledge using rodent models in two ways: first, by examining the long-lasting effects of repeated toluene inhalation during adolescence on several measures of executive function in adulthood and second, by studying the effects of acute toluene inhalation on risk/reward decision making and related neurocircuitry. Repeated inhalation of toluene during adolescence blunted acquisition of operant and Pavlovian learning in adulthood without affecting probabilistic discounting, progressive ratio breakpoint, latent inhibition or reversal learning. Acute toluene vapor inhalation, however, caused a dose-dependent, sex-independent deficit in behavioral flexibility during probabilistic discounting, a pattern that implicates dysfunctional medial prefrontal cortex (mPFC) activity. To address this hypothesis, we virally expressed the genetically encoded calcium sensor GCaMP6f in glutamatergic mPFC neurons and monitored calcium transients during during task performance using in vivo fiber photometry. Peaks in GCaMP6f activity shifted from pre-risky to pre-safe choice during contingency updating, an effect that was eliminated by acute toluene exposure. mPFC activity in toluene-treated animals also did not distinguish between risky/large wins and safe/small wins. Interestingly, previous studies from our lab demonstrated a toluene-induced long-term depression of AMPA-mediated synaptic activity in deep-layer mPFC neurons. This effect was dependent on endocannabinoids (EC) synthesis and presynaptic cannabinoid receptor (CB1R) function. Here, we found that pharmacological inhibition of CB1Rs in the mPFC or systemically did not mitigate toluene’s effect on probabilistic discounting. Behavioral flexibility in this task also depends on functional mPFC-basolateral amygdala (BLA) neurocircuitry. Electrophysiological interrogation of BLA neurons innervated by the mPFC using ex vivo slice electrophysiology and optogenetics revealed a CB1R-dependent decrease in excitatory synaptic transmission following toluene application. These data elucidate learning and behavioral flexibility deficits caused by toluene, including insights on potential mPFC-BLA- and CB1R-dependent mechanisms

Single-Stage, 3.4:1-Pressure-Ratio Aspirated Fan Developed and Demonstrated

Researchers are constantly pursuing technologies that will increase the performance of gas turbine engines. The aspirated compressor concept discussed here would allow the compression system to perform its task with about one-half of the compressor blades. To accomplish this, the researchers applied boundary layer control to the blades, casing, and hub. This method of boundary layer control consisted of removing small amounts of air from the main flow path at critical areas of the compressor. This bleed air could be used by other systems such as engine cooling or could be re-injected into lower pressure areas that require air for enhanced performance. This effort was initiated by the Massachusetts Institute of Technology (MIT) in response to a solicitation from the Defense Advanced Research Projects Agency (DARPA) who sought to advance research in flow control technology. The NASA Glenn Research Center partnered with MIT (principal investigator), Honeywell Aircraft Engines (cycle analysis, structural analysis, and mechanical design), and Pratt & Whitney (cycle analysis and aero-analysis) to conceptualize, design, analyze, build, and test the aspirated fan stage. The aero-design and aero-analysis of this fan stage were jointly executed by MIT and Glenn to minimize the amount of bleed flow needed and to maintain the highest efficiency possible (ref. 1). Mechanical design issues were complicated by the need to have a shrouded rotor with hollow blades, with rotor stress levels beyond the capabilities of titanium. The high stress issues were addressed by designing a shroud that was filament wound with a carbon fiber/epoxy matrix, resulting in an assembly that was strong enough to handle the high stresses. Both the rotor (preceding photographs) and stator (following photograph) were fabricated in two halves and then bolted together at the hub and tip, permitting the bleed passages to be machined into each half before assembly

Performance characterization and transient investigation of multipropellant resistojets

The multipropellant resistojet thruster design initially was characterized for performance in a vacuum tank using argon, carbon dioxide, nitrogen, and hydrogen, with gas inlet pressures ranging from 13.7 to 310 kPa (2 to 45 psia) over a heat exchanger temperature range of ambient to 1200 C (2200 F). Specific impulse, the measure of performance, had values ranging from 120 to 600 seconds for argon and hydrogen respectively, with a constant heat exchanger temperature of 1200 C (2200 F). When operated under ambient conditions typical specific impulse values obtained for argon and hydrogen ranged from 55 to 290 seconds, respectively. Performance measured with several mixtures of argon and nitrogen showed no significant deviation from predictions obtained by directly weighting the argon and nitrogen individual performance results. Another aspect of the program investigating transient behavior, showed responses depended heavily on the start-up scenario used. Steady state heater temperatures were achieved in 20 to 75 minutes for argon, and in 10 to 90 minutes for hydrogen. Steady state specific impulses were achieved in 25 to 60, and 20 to 60 minutes respectively

Space Station Technology Summary

The completion of the Space Station Propulsion Advanced Technology Programs established an in-depth data base for the baseline gaseous oxygen/gaseous hydrogen thruster, the waste gas resistojet, and the associated system operations. These efforts included testing of a full end-to-end system at National Aeronautics and Space Administration (NASA)-Marshall Space Flight Center (MSFC) in which oxygen and hydrogen were generated from water by electrolysis at 6.89 MPa (1,000 psia), stored and fired through the prototype thruster. Recent end-to-end system tests which generate the oxygen/hydrogen propellants by electrolysis of water at 20.67 MPa (3,000 psia) were completed on the Integrated Propulsion Test Article (IPTA) at NASA-Johnson Space Center (JSC). Resistojet testing has included 10,000 hours of life testing, plume characterization, and electromagnetic interference (EMI) testing. Extensive 25-lbf thruster testing was performed defining operating performance characteristics across the required mixture ratio and thrust level ranges. Life testing has accumulated 27 hours of operation on the prototype thruster. A total of seven injectors and five thrust chambers were fabricated to the same basic design. Five injectors and three thrust chambers designed to incorporate improved life, performance, and producibility characteristics are ready for testing. Five resistojets were fabricated and tested, with modifications made to improve producibility. The lessons learned in the area of producibility for both the O2/H2 thrusters and for the resistojet have resolved critical fabrication issues. The test results indicate that all major technology issues for long life and reliability for space station application were resolved

Process Variation: Demonstrating Responsibility

W. Edwards Deming preached that understanding variation is of paramount importance. He created the Red Bead Experiment (DRBE) to illustrate that variation is present in all processes and that utimately, management, not the willing worker, is responsible for the variability that is inherent in a process. We modify DRBE to demonstrate these lessons to undergraduate management and accounting students. Our results indicate that DRBE is a successful way for these students to I cam how variation applies to their respective studies

Measurement of Flow Pattern Within a Rotating Stall Cell in an Axial Compressor

Effective active control of rotating stall in axial compressors requires detailed understanding of flow instabilities associated with this compressor regime. Newly designed miniature high frequency response total and static pressure probes as well as commercial thermoanemometric probes are suitable tools for this task. However, during the rotating stall cycle the probes are subjected to flow direction changes that are far larger than the range of probe incidence acceptance, and therefore probe data without a proper correction would misrepresent unsteady variations of flow parameters. A methodology, based on ensemble averaging, is proposed to circumvent this problem. In this approach the ensemble averaged signals acquired for various probe setting angles are segmented, and only the sections for probe setting angles close to the actual flow angle are used for signal recombination. The methodology was verified by excellent agreement between velocity distributions obtained from pressure probe data, and data measured with thermoanemometric probes. Vector plots of unsteady flow behavior during the rotating stall regime indicate reversed flow within the rotating stall cell that spreads over to adjacent rotor blade channels. Results of this study confirmed that the NASA Low Speed Axial Compressor (LSAC) while in a rotating stall regime at rotor design speed exhibits one stall cell that rotates at a speed equal to 50.6 percent of the rotor shaft speed

Experimental Investigation of Rotating Stall in a Research Multistage Axial Compressor

A collection of experimental data acquired in the NASA low-speed multistage axial compressor while operated in rotating stall is presented in this paper. The compressor was instrumented with high-response wall pressure modules and a static pressure disc probe for in-flow measurement, and a split-fiber probe for simultaneous measurements of velocity magnitude and flow direction. The data acquired to-date have indicated that a single fully developed stall cell rotates about the flow annulus at 50.6% of the rotor speed. The stall phenomenon is substantially periodic at a fixed frequency of 8.29 Hz. It was determined that the rotating stall cell extends throughout the entire compressor, primarily in the axial direction. Spanwise distributions of the instantaneous absolute flow angle, axial and tangential velocity components, and static pressure acquired behind the first rotor are presented in the form of contour plots to visualize different patterns in the outer (midspan to casing) and inner (hub to mid-span) flow annuli during rotating stall. In most of the cases observed, the rotating stall started with a single cell. On occasion, rotating stall started with two emerging stall cells. The root cause of the variable stall cell count is unknown, but is not attributed to operating procedures

Application of Synthetic Jets to Reduce Stator Flow Separation in a Low Speed Axial Compressor

Flow control using synthetic jet injection has been applied in a low speed axial compressor. The synthetic jets were applied from the suction surface of a stator vane via a span-wise row of slots pitched in the streamwise direction. Actuation was provided externally from acoustic drivers coupled to the vane tip via flexible tubing. The acoustic resonance characteristics of the system, and the resultant jet velocities were obtained. The effects on the separated flow field for various jet velocities and frequencies were explored. Total pressure loss reductions across the vane passage were measured. The effect of synthetic jet injection was shown to be comparable to that of pulsatory injection with mass addition for stator vanes which had separated flow. While only a weak dependence of the beneficial effect was noted based on the excitation frequency, a strong dependence on the amplitude was observed at all frequencies

Impulsive Injection for Compressor Stator Separation Control

Flow control using impulsive injection from the suction surface of a stator vane has been applied in a low speed axial compressor. Impulsive injection is shown to significantly reduce separation relative to steady injection for vanes that were induced to separate by an increase in vane stagger angle of 4 degrees. Injected flow was applied to the airfoil suction surface using spanwise slots pitched in the streamwise direction. Injection was limited to the near-hub region, from 10 to 36 percent of span, to affect the dominant loss due to hub leakage flow. Actuation was provided externally using high-speed solenoid valves closely coupled to the vane tip. Variations in injected mass, frequency, and duty cycle are explored. The local corrected total pressure loss across the vane at the lower span region was reduced by over 20 percent. Additionally, low momentum fluid migrating from the hub region toward the tip was effectively suppressed resulting in an overall benefit which reduced corrected area averaged loss through the passage by 4 percent. The injection mass fraction used for impulsive actuation was typically less than 0.1 percent of the compressor through flow