Barrett, The Honors College Thesis/Creative Project Collection
Barrett, The Honors College at Arizona State University proudly showcases the work of undergraduate honors students by sharing this collection exclusively with the ASU community.
Barrett accepts high performing, academically engaged undergraduate students and works with them in collaboration with all of the other academic units at Arizona State University. All Barrett students complete a thesis or creative project which is an opportunity to explore an intellectual interest and produce an original piece of scholarly research. The thesis or creative project is supervised and defended in front of a faculty committee. Students are able to engage with professors who are nationally recognized in their fields and committed to working with honors students. Completing a Barrett thesis or creative project is an opportunity for undergraduate honors students to contribute to the ASU academic community in a meaningful way.
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- Creators: Department of Physics
Description
Women are twice as likely as men to develop Major Depressive Disorder (MDD), and current MDD therapies are only effective for about a third of patients. Hormonal transitions, specifically those involving estradiol (E2), have been found to contribute to this increased vulnerability in women. This study aimed to investigate potential mechanisms underlying the sex differences seen in MDD vulnerability, specifically the role of E2. The brain region-specific changes induced by chronic stress differ for female rats than for male rats. Therefore, we aimed to determine the effects of sex and chronic stress on E2 expression in four brain regions: the hippocampus, medial prefrontal cortex, amygdala, and cerebellum. Sprague-Dawley rats (n = 48, 24 males, 24 females; n=12/Tx group) were subjected to daily wire mesh restraint stress (6 h/21 days), and were euthanized and dissected the day following the end of chronic restraint stress (day 22). Ultra high-pressure liquid chromatography-mass spectroscopy was used to directly measure E2 in the brain regions. Quantitative real-time PCR was used to indirectly assess E2 expression via mRNA for aromatase (ARO-L) and estrogen receptors (ERβ, ERɑ, and GPR30), as well as expression of inflammatory cytokines (IL-1β and TNF-ɑ). Our findings suggest that chronic stress may lead to changes in local estradiol expression in the brain that are both sex-dependent and brain region-specific, while the data are preliminary given the small sample size. We found that expression of ARO-L mRNA, a measure of local E2 production, tended to increase in the HIPP, but decrease in the mPFC following chronic stress, and in the mPFC this pattern was only observed in males. Local estradiol production in the brain seems to act as a potential compensatory mechanism in the hippocampus, but as a protective mechanism in the mPFC, which is highly sensitive to chronic stress.
ContributorsSmith, Elliot Ann (Author) / Conrad, Cheryl (Thesis director) / Presson, Clark (Committee member) / Department of Psychology (Contributor) / Department of Physics (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
I examine the effects of metallicity on solar mass stellar evolution, trying to replicate a previous result in Windhorst et.al., 2018, in which a zer metallicity solar mass star did not reach the AGB, and thus may turn into a helium white dwarf. In trying to replicate this result, I used the M.E.S.A. stellar evolution code and was unable to reproduce this result. While M.E.S.A has undergone several updates since the previous result was obtained, more current evidence suggests that this may have been a one-time occurrence, as no helium white dwarfs were produced for low-metallicity models. Nonetheless, interesting results were obtained, including a lowest metallicity value for which CNO burning does not significantly contribute during the main sequence, 1 −10 Z , which produces noticeable effects on post main sequence evolution. All models are run with no rotation, one solar mass, and a series of MESA parameters kept constant, with the only exception being metallicity. Any metallicity value listed as Nd −10 is an absolute mass fraction, and Z is relative to solar metallicity, 2d*10 −2 .
ContributorsTompkins, Scott Andrew (Author) / Windhorst, Rogier (Thesis director) / Young, Patrick (Committee member) / School of Earth and Space Exploration (Contributor) / Department of Physics (Contributor) / Barrett, The Honors College (Contributor)
Created2019-12
Description
Although extracellular throughout their lifecycle, trypanosomes are able to persist despite strong host immune responses through a process known as antigenic variation involving a large, highly diverse family of surface glycopro- tein (VSG) genes, only one of which is expressed at a time. Previous studies have used mathematical models to investigate the relationship between VSG switching and the dynamics of trypanosome infections, but none have explored the role of multiple VSG expression sites or the contribution of mosaic gene conversion events involving VSG pseudogenes.
ContributorsKoury, Michael Andrew (Author) / Taylor, Jesse (Thesis director) / Gumel, Abba (Committee member) / Department of Physics (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
This research evaluates the capabilities of typical radiological measures and dual-energy systems to differentiate common kidney stones materials: uric acid, oxalates, phosphates, struvite, and cystine. Two different X-ray spectra (80 kV and 120 kV) were applied and the dual-energy ratio of individual kidney stones was used to figure out the discriminability of different materials. A CT cross-section with a prospective kidney stone was analyzed to see the capabilities of such a technique. Typical radiological measures suggested that phosphates and oxalate stones can be distinguished from uric acid stones while dual-energy seemed to prove similar effectiveness.
ContributorsDelafuente, Nicholas William (Author) / Rez, Peter (Thesis director) / Alarcon, Ricardo (Committee member) / Department of Physics (Contributor) / Economics Program in CLAS (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
The current observable universe is made of matter due to baryon/antibaryon asymmetry. The Deep Underground Neutrino Experiment is an international experiment through the Fermi National Accelerator Laboratory that will study neutrinos. In this study, the detection efficiency for low energy supernova neutrinos was examined in order to improve energy reconstruction for neutrino energies less than 40 MeV. To do this, supernova neutrino events were simulated using the LarSoft simulation package with and without background. The ratios between the true data and reconstructed data were compared to identify the deficiencies of the detector, which were found to be low energies and high drift times. The ratio between the true and reconstructed data was improved by applying the physical limits of the detector. The efficiency of the improved ratio of the clean data was found to be 93.2% and the efficiency of the improved ratio with the data with background was 82.6%. The study suggests that a second photon detector at the far wall of the detector would help improve the resolutions at high drift times and low neutrino energies.
ContributorsProcter-Murphy, Rachel Grace (Co-author) / Procter-Murphy, Rachel (Co-author) / Ritchie, Barry (Thesis director) / LoSecco, John (Committee member) / School of Earth and Space Exploration (Contributor) / Department of Physics (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
In this project, we created a code that was able to simulate the dynamics of a three site Hubbard model ring connected to an infinite dissipative bath and driven by an electric field. We utilized the master equation approach, which will one day be able to be implemented efficiently on a quantum computer. For now we used classical computing to model one of the simplest nontrivial driven dissipative systems. This will serve as a verification of the master equation method and a baseline to test against when we are able to implement it on a quantum computer. For this report, we will mainly focus on classifying the DC component of the current around our ring. We notice several expected characteristics of this DC current including an inverse square tail at large values of the electric field and a linear response region at small values of the electric field.
ContributorsJohnson, Michael (Author) / Chamberlin, Ralph (Thesis director) / Ritchie, Barry (Committee member) / School of Mathematical and Statistical Sciences (Contributor) / Department of Physics (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
This thesis project is focused on studying the number field sieve. The number field sieve is a factoring algorithm which uses algebraic number theory and is one of the fastest known factoring algorithms today. Factoring large integers into prime factors is an extremely difficult problem, yet also extremely important in cryptography. The security of the cryptosystem RSA is entirely based on the difficulty of factoring certain large integers into a product of two distinct large primes. While the number field sieve is one of the fastest factoring algorithms known, it is still not efficient enough to factor cryptographic sized integers.
In this thesis we will examine the algorithm of the number field sieve and discuss some important advancements. In particular, we will focus on the advancements that have been done in the polynomial selection step, the first main step of the number field sieve. The polynomial selected determines the number field by which computations are carried out in the remainder of the algorithm. Selection of a good polynomial allows for better time efficiency and a higher probability that the algorithm will be successful in factoring.
In this thesis we will examine the algorithm of the number field sieve and discuss some important advancements. In particular, we will focus on the advancements that have been done in the polynomial selection step, the first main step of the number field sieve. The polynomial selected determines the number field by which computations are carried out in the remainder of the algorithm. Selection of a good polynomial allows for better time efficiency and a higher probability that the algorithm will be successful in factoring.
ContributorsLopez, Rose Eleanor (Co-author) / Lopez, Rose (Co-author) / Childress, Nancy (Thesis director) / Jones, John (Committee member) / Pomerance, Carl (Committee member) / School of Music (Contributor) / Department of Physics (Contributor) / School of Mathematical and Statistical Sciences (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
In this project we are analyzing the diamond-titanium interface as it applies to diamond-based diode devices, including alpha particle, proton, and neutron detectors. This is done through the fabrication of an O-terminated B-doped diamond sample with a 20 Å Ti / 10 Å Pt overlayer which was then annealed and examined via X-ray photoelectron spectroscopy (XPS). It was discovered that after annealing the sample at temperatures ranging from 400 C - 900 C that TiC was not formed at any point during this experiment. Possible reasons for this include a lack of sufficient titanium in order to form TiC and over oxygenating the diamond surface before the metal was deposited.
ContributorsJohnson, Holly (Author) / Zaniewski, Anna (Thesis director) / Nemanich, Robert (Committee member) / Department of Physics (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
The ASU Compact X-ray Free Electron Laser (CXFEL) is a first of its kind instrument that will illuminate the processes of life and allow scientists to create more effective treatments for disease. The dimensions of the linear accelerator (LINAC) cavities must remain stable during operation, for a change in the geometry alters the standing wave microwave energy resonance within the cavities and leads to reflected rather than coupled and useful microwave energy to electric field coupling. This disturbs the electron bunch acceleration dynamics critical to the ultimate generation of x-ray pulses. Cooling water must be supplied to the electron generating RF-GUN, and linear accelerator (LINAC) structures at unique flowrate and temperature setpoints that are specific to the operating mode of the CXFEL. Design specifications for the water supply to the RF-GUN and three LINACs and were made for the nominal operating mode, which adds a 3 kW heat load to the water. To maintain steady cavity dimensions, water must be supplied to each device under test at 30.0 ºC ± 0.06 ºC. The flowrate of water must be 3.5 GPM to the RF-GUN and 2.5 GPM to each of the three LINACs with ± 0.01 GPM flowrate resolution. The primary function of the Dedicated-Precision Thermal Trim Unit (D-PTTU) is to control the flowrate and temperature of water supply to each device under test. A simplified model of the system was developed to select valves that would meet our design specifications for flowrate and temperature control. After using this model for valve selection, a detailed system model was created to simulate relevant coupled-domain physics of the integrated system. The detailed system model was used to determine the critical sensitivities of the system and will be used to optimize the performance of the system in the future. Before the detailed system model can be verified and tuned with experiments, the sensors were calibrated in an ice-bath to ensure the sensors measure accurate and precise values. During initial testing, the D-PTTU was able to achieve ± 0.02 ºC temperature resolution, which exceeds the design specification by a factor of three.
ContributorsGardeck, Alex John (Author) / Holl, Mark (Thesis director) / Smith, Dean (Committee member) / Department of Physics (Contributor) / Mechanical and Aerospace Engineering Program (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Similar to the real numbers, the p-adic fields are completions of the rational numbers. However, distance in this space is determined based on divisibility by a prime number, p, rather than by the traditional absolute value. This gives rise to a peculiar topology which offers significant simplifications for p-adic continuous functions and p-adic integration than is present in the real numbers. These simplifications may present significant advantages to modern physics – specifically in harmonic analysis, quantum mechanics, and string theory. This project discusses the construction of the p-adic numbers, elementary p-adic topology, p-adic continuous functions, introductory p-adic measure theory, the q-Volkenborn distribution, and applications of p-adic numbers to physics. We define q-Volkenborn integration and its connection to Bernoulli numbers.
ContributorsBurgueno, Alyssa Erin (Author) / Childress, Nancy (Thesis director) / Jones, John (Committee member) / School of Mathematical and Statistical Sciences (Contributor, Contributor, Contributor) / Department of Physics (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05