Stander Symposium: Honors Program

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  Academic Achievement Gap of ELL Students after the COVID-19 Pandemic

  Megan K. Buzzanca

  As ELLs continue to be the fastest-growing population of K-12 public school students, itis critical to examine how ELLs were impacted by the challenges of the COVID-19 pandemic.ELL students struggled to transition from in-class to remote learning because many educationalmaterials were not appropriate for their learning style, both before and because of COVID. (Long,2022). Now, some of these ELL students are approximately 2-3 years behind their English nativepeers in terms of academic progress. The following research will have a foundation through aliterature review as well as a focus qualitative study on ELL students and teachers. The study willgive personal accounts of how COVID-19 has impacted the ELL student’s life in 2020 andhow it continues to impact their lives today. In addition, this study will analyze effective resourcesto further support the learning of ELL students.

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  Advancing Sickle Cell Disease Management: Introducing a High-Throughput Test for Irreversibly Sickled Cells

  John-Paul Stefano Bugada

  Sickle cell disease is an inherited red blood cell disorder caused by abnormal hemoglobin in the cells. This hemoglobin causes the cells to temporarily become rigid and shaped like a “C” or sickle. Sickle cells can get stuck and block blood flow leading to pain, infections, and other serious complications. The percentage of irreversibly sickled cells (ISCs) is an indication of how patients are managing their sickle cell disease. Currently, the best way to quantify ISCs is to use a microscope to count the normal red blood cells and ISCs and then manually calculate a percentage. This method is both time-consuming and subjective, and as a result, it is not being used even though it can help doctors better understand how patients are managing their disease. Through my research at Cincinnati Children’s Hospital, we developed a high-throughput ISC test that is faster, more efficient, and more consistent than the current method. This new method uses machine learning analysis software to sort through tens of thousands of pictures of cells from a patient and determine the percentage of ISCs. The new test correlates with the current method without having to train people to recognize sickle cells or manually count them. We believe that this test will provide more accessible, accurate, and consistent monitoring of sickle cell disease while reducing subjectivity, costs, and time.

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  Anti-predator Behavior in Response to Conspecific Visual, Olfactory, and Damage Cues in the Three-spined Stickleback

  Claire Elizabeth Van Meter

  Predation is a major source of mortality for prey, which creates a selective pressure to avoid predators whenever possible. By using alarm cues produced by conspecifics, individuals can be alerted of nearby predators without coming into direct contact with them. However, we do not know whether individuals can distinguish between different kinds of conspecific cues and if some types of cues may indicate a more severe predation threat compared to others. I studied the ability of the three-spined stickleback to distinguish between environmental cues by exposing conspecifics to 4 different treatments in a randomized order: 1) Control (control olfactory cues with an unexposed demonstrator), 2) Visual Only (control olfactory cues with an exposed demonstrator), 3)Visual and Stress (stress cues with an exposed demonstrator), and 4) Visual, Stress, and Damage (stress and damage cues with an exposed demonstrator). For 5 minutes before and after exposure to the cues, I watched for four key defensive behaviors: hiding in plants, hiding in the gravel at the bottom of the tank, thigmotaxis, and shoaling. Directly after each assay, I placed the focal subject in 200ml of RO water in a 600ml beaker for 1 hour to collect waterborne cortisol. It was found that observer hiding behavior increased when observers were exposed to visual cues of stressed conspecifics paired with either olfactory cues of stressed conspecifics or conspecific stress and damage cues. Observers also shoaled less when exposed to visual cues paired with olfactory stress cues, but not with visual cues alone, or visual cues paired with stress and damage cues. Males shoaled more than females, but hid less than females. There was no observed change in behavior for demonstrators, regardless of what cues were added. There were also no differences in waterborne cortisol levels for each of the treatments.

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  Assessing the Behavioral Effects of Conditional SERCA2 Deletion in central GABAergic Neurons

  Hayden Nathaniel Ott

  The regulation of calcium (Ca2+), a critical ionic messenger, has been implicated in a wide variety of cellular processes including gene transcription, muscle contraction, and neurotransmitter release. The sarco-endoplasmic reticulum Ca2+ ATPase (SERCA), an intracellular regulator of Ca2+ homeostasis that functions by sequestering Ca2+ into the endoplasmic reticulum (ER), is a particular molecule of interest. Previous research has implicated dysfunction of SERCA regulation as a contributor to neurodegenerative diseases such as Alzheimer’s disease and neurodevelopmental disorders including Autism-spectrum disorder (ASD). In this study, we sought to further understand the role of SERCA2 in behavior through the creation of a novel transgenic mouse line that is characterized by conditional deletion of SERCA2 in the brain’s γ-aminobutyric acid (GABA)-ergic inhibitory neurons. Male and female mice of this line then underwent a behavioral battery assessing motor function, anxiety and depressive-like behaviors. The results of this study contribute to our understanding of SERCA's role in behavior and the mechanisms contributing to complex neurodegenerative and neurodevelopmental disorders.

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  Behavioral responses of two color morphs of the Eastern Red-backed Salamander (Plethodon cinereus) to novel urban environments

  Amy Q. Friemoth

  Human modified landscapes can provide challenging new environments that can lead to rapid changes in species traits. In temperate forest ecosystems, salamanders play a critical role in forest floor dynamics, but populations are now faced with rapid habitat change, which can lead local extinctions unless these species behaviorally adapt. The Eastern Red-backed Salamander, Plethodon cinereus, is the most common salamander species in Ohio and serves as a model species for examining the effects of anthropogenic change. Further, the Eastern Red-backed Salamander poses two common color morphs (striped and unstriped) that appear to differ in their responses to environmental change. Here, I investigated how urbanization differentially influences behavioral responses of the two color morphs of the Eastern Red-backed Salamander. I collected 20 striped and 20 unstriped individuals from Caesar Creek State Park, Ohio. I exposed them to a novel environment (cement paver) and novel objects (anthropogenic waste) to test exploration and neophobia behaviors. We are examining these variations in behavior and will run statistical models to test whether the morphs differ in their behavioral responses to these anthropogenic pressures. Based on previous studies, we expect the striped morph to display more bold behaviors and ultimately do better with urbanization. This work will highlight whether both color morphs persist with rapid habitat modification which will have important implications for other North American salamanders as many species share the same color phenotypes and may be responding similarly.

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  Benefits of a Community Reentry Intervention for Reentry Self-Efficacy in Homeless Shelter Residents With Past Incarceration

  Kathryn E. Hurley

  The U.S. has one of the highest levels of incarceration and recidivism in the world (American Civil Liberties Union, 2022; U.S. Department of Justice, n.d). Several factors contribute to recidivism, including the loss of monetary funds and loss of housing upon incarceration. Homelessness especially predicts recidivism. It has been found to increase the risk of recidivism by almost 50% (Jacobs & Gottlieb, 2020). Within the context of a long-term ongoing participatory community action research project in homeless shelters (Reeb et al., 2024), this study examined the benefit of reentry support sessions within the homeless shelter environment, with an attempt to overcome barriers in utilizing community resources. Twenty previously incarcerated, unhoused men participated in a reentry support session within St. Vincent De Paul’s Gateway Shelter for Men (Dayton, Ohio). The reentry support session was developed in collaboration with the Montgomery County (Ohio) Office of Reentry. Participants completed a measure of self-efficacy for community reentry at pre- and post-session, followed by a brief interview to identify their plans for obtaining reentry services in the community. In support of Hypothesis 1, it was found that the self-efficacy for coping with community reentry improved from pre- to post-intervention. Consistent with hypothesis 2, residents both with and without a disability benefited from the session at approximately equal levels. Post-session interviews revealed that a majority of residents expressed intentions to obtain additional reentry-related resources. Keywords: recidivism, community reentry, homeless, disability, self-efficacy, participatory community action research in homeless shelters

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  Beyond Technology: Social Predictors of Energy Efficiency in Industrial Facilities

  Garret B. Cowdery

  Energy is the lifeblood of the industrialized world with electrical energy expected by the National Renewable Energy Laboratory (NREL) to increase 25% between 2016 to 2050 in the United States. Combined with the ever-present climate crisis, energy-efficient buildings are becoming increasingly important to conserve resources and alleviate strain on aging energy systems. The Industrial Assessment Center (IAC) program through the US Department of Energy aims to reduce the consumption of large, single-site energy users, industrial and commercial buildings, through comprehensive energy audits. Such investigations find that energy-efficient structures are a technological challenge as much as social. The mentality of building occupants towards energy use strongly impacts the efficiency of the building with the energy conscientiousness of the inhabitants being a key factor in maximizing theoretical performance. Not in My Backyard (NIMBY) is a social phenomenon where communities rise in opposition to controversial facilities that serve to upset community wellbeing. These are generally energy-intensive projects that may detract from the natural beauty or environmental health of an area. The negative reaction originates from difficult-to-measure factors such as personal attitudes and trust between involved parties but can be loosely predicted by specific demographic quantities. This investigation aimed to primarily analyze the quantity, scale, and quality of community energy systems at the county level of Ohio in conjunction with collected IAC data and NIMBY demographics to identify potential external predictors for industrial energy intensity based on NIMBY sensitivity. Ultimately, only a weak correlation is found between industrial facility energy usage and the listed attributes, but the investigation paints a vivid demography of people, energy resources, and industrial agglomeration while emphasizing and supporting the need for continual research into the social functions that drive technical success.

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  Characterizing the Broadband Frequency Response of Pressure-Sensitive Paint

  Charles Jerome Strunc

  Pressure-Sensitive Paint (PSP) is an exceptional tool used to gather the pressure distribution on a model during a wind tunnel test (or other similar methods of testing) in the form of a high-resolution image. In order to use the PSP effectively, however, an intimate understanding of the paint being employed must first be established and the reaction time of the paint being developed must be pushed to the limit. These goals in my work are accomplished by sending various novel PSP creations through a resonance tube that was designed, constructed, and applied here on campus. The resonant qualities of an air column in the tube are exploited to increase the magnitude of the rapid pressure fluctuations coming from a speaker system. The pressure readings from the paint inside the tube will be compared to the more exact results from a pressure transducer to determine the frequency response time of the paint, thus allowing the testing of novel PSP at any desired frequency range between 0 and 60 kHz.

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  Creating a More Meaningful AI Tournament: Statistical Insights from the Game of Catan

  Aidan P. Reichenberg

  As the 14th most popular board game of all time, Catan distinguishes itself through a unique combination of randomness, strategy, and player interaction. This study explores the application of artificial intelligence (AI) to the game of Catan, utilizing the Catanatron framework to compare seven unique agents through an AI tournament.Central to this analysis is the application of statistically significant methods for comparison. Establishing quantifiable differences in the relative strength between agents is paramount in creating meaningful, repeatable findings in AI research. By generating statistically significant results, this study aims to create a foundation for comparing future agents created to play the game of Catan. Furthermore, the methods used for comparing agents in this study can be applied to similar games.This study adopts a tournament format to compare the agents, creating groups based on the initial findings of Bryan Collazo, creator of Catanatron. I placed Collazo’s original agents in opposition to each other. The first tournament round employing these agents builds a foundation for larger simulations. This study identifies the strongest agents, analyzes the nuances of their strategy, and quantifies their relative strength by looking at the statistical significance of the results.The results of this analysis contribute to AI research by producing meaningful comparisons between agents and providing a framework for future comparison that can extend to similar multiplayer games.

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  Design Space Exploration for a Novel Self-Healing Elastomer, Informed by Bayesian Optimization

  Robert M. Drexler

  Self-healing elastomers are an emerging class of materials capable of mitigating vulnerability to externally-induced damage. Recent advancements in polymer chemistry have led to self-healing elastomers that are 3D-printable, exhibit real-time self-healing in the absence of external stimuli (e.g., heat, light), and use commercially available (COTS) precursors to enable production at scale. However, at present, the trade-offs between virgin mechanical properties and self-healing efficiency are not well known. To address this research opportunity, this talk presents an experimental program – informed by a Bayesian optimization platform – to (a) facilitate design space exploration and (b) investigate the interplay between virgin mechanical properties (i.e., hardness and toughness) and self-healing efficiency (e.g., ratio of healed toughness to virgin toughness) as chemical composition is varied. The material of interest is BeckOHflex, a new acrylate/thiol-ene elastomer that exhibits real-time, autonomous self-healing and is exclusively prepared from COTS precursors. The experimental design was conducted by varying the crosslinker and thiol components from 0-10% by volume while holding the molar ratio of acrylate and photoinitiator constant. Test samples were cast in custom silicone molds and cured using an external UV lamp. Hardness data was obtained using an analog Shore OO durometer, and mechanical property data was collected through uniaxial tension testing. Informed by previous-iteration experimental inputs (chemical composition) and the resulting outputs from mechanical testing (virgin hardness, virgin toughness, and self-healing efficiency), a Bayesian optimization platform (EBDO+) was used to suggest next-iteration experimental inputs. Through this iterative process of synthesizing, testing, and analyzing different compositions throughout the experimental campaign, a well-defined Pareto frontier will be determined to bound the design space, allowing for a fundamental, quantitative understanding of tradeoffs between virgin mechanical properties and self-healing efficiency. It is expected that the Pareto frontier will be determined after tens of experiments out of a possible 2,000+ discrete input parameter combinations.

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  Development of a Machine Learning-Based Program to Measure Cell Proliferation

  Adam J. Jones

  Many tools have emerged to investigate the functioning of biological systems, especially when in contact with foreign substances. In vitro procedures are often used due to their cost effectiveness and suitability for high-throughput experiments. These procedures collect basic measurements, such as toxicity and biocompatibility, that provide insight into the compatibility and safety of a substance.In vitro toxicity tests are favored for their expediency, affordability, and consistent outcomes. Quantitative methodologies, like colorimetric and fluorometric assays, offer objectivity and high-throughput analysis. However, they require lengthy incubation times and only provide a single metric. Microscopy-based methods provide more information in terms of cell morphology and localization, and can be captured quickly without the need for reagents and incubation. Yet, this method requires specialized expertise and is prone to subjective biases and variations based on the region-of-interest.Given the limitations of microscopy-based approaches, there is a growing interest in leveraging machine learning (ML) to streamline and enhance cell analysis. This study aims to develop an ML-based approach to evaluate cell count and confluency from microscope images and compare its performance to the colorimetric assay, CCK8. The CCK8 assay, which releases a dye when metabolized by live cells, served as the benchmark for comparison. The ML-based method, developed using Ilastik, CellProfiler, and Python, segments microscopy images into cell and background regions, followed by erosion for cell boundary enhancement. CellProfiler subsequently quantifies the cell count and confluency from the processed images.This novel ML-based approach offers expedited analysis, while mitigating the inherent subjectivity and error associated with conventional techniques. This approach also eliminates the need for excess reagents and waste associated with quantitative assays. In conclusion, this technique presents an alternative in scenarios where traditional assays are impractical, such as with low cell counts or when cells must be reused.

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  Discovery of Novel Mechanisms During the Biodegradation of Polymer Coatings by an Environmental Strain of Aureobasidium

  Paige Aileen King

  In order to create novel sustainable and biodegradation resistant coating formulations that do not include toxic additives to humans and/or the environment, the mechanistic complexity of the biodegradation process has to be simplified into general categories and knowledge gaps. This approach will truly identify where active biodegradation stops by microorganisms and where purely chemical hydrolysis and degradation begins. The specific research focus of my project is on the essential role of water and secreted hydrolytic proteins play in the movement and activity of polymer degrading fungi. The result of this focus could ultimately identify if degradation may be attributed to thermodynamic potentials of the organism, polymer coating, or both the microorganisms and polymer coating. My project will focus on a strain of yeast (Aureobasidium sp. W12) isolated and identified from degraded polymer coatings inside of Air Force cargo aircraft. I will determine the culture conditions that stimulate the release of hydrolytic proteins from A. sp. W12 and then use defined polymer coatings and techniques to understand how these proteins are affecting the degradation of polyester polyurethane coating over time as biofilms or facilitate the condensation of water on the surface below the relative dew point during the degradation of the coating. The result of my summer project should be the first identification and key hydrolytic enzymes and mechanisms used by A. sp. W12 in the degradation of polyester polyurethane coatings.

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  Effects of Paternal Heat Exposure and Parental Care on the Development of Offspring in Gasterosteus aculeatus

  Emma R. Borgert

  Humans are profoundly altering the abundance and distribution of organisms via climate change. In particular, warming temperatures are affecting marine and freshwater ecosystems by increasing physiological stress, limiting growth, and decreasing dissolved oxygen. With all this change occurring, an understanding of how organisms are going to cope is crucial. Transgenerational plasticity – when parental experiences alter offspring traits - can allow organisms to rapidly adapt to environmental change. Previous literature has focused on the role of maternal experiences on offspring traits, but paternal experiences are just as important. Fathers can influence their offspring in multiple ways, including changes via both sperm and paternal care behaviors. Three-spined sticklebacks, Gasterosteus aculeatus, are a small fish found in freshwater and marine ecosystems with paternal-only care. Many populations are facing the threats of drought and wildfire, making it important to understand how they will adapt to climate change. To understand how paternal heat exposure alters offspring development, I exposed parents to cool (~17°C) or warm (~20°C) water temperature and then manipulated whether fathers provided paternal care or offspring were artificially aerated; this generated offspring that received cues of heat exposure from gametes alone versus from gametes and paternal care. I found that males exposed to warmer temperatures were less colorful but provided the same amount of care overall to their offspring. Offspring of cool-temperature males were shorter than offspring of warm-temperature parents, but only when males provided paternal care. Offspring survival was not affected by parental heat exposure but was lower when offspring themselves were exposed to warm temperatures. Overall, these results suggest that heat exposure alters both paternal and offspring traits, and that the effects on offspring depend on the mechanism of paternal effects (care versus sperm).

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  Hippo, Wnt, and JNK Pathway Interactions in a Drosophila Colorectal Cancer Model

  Michael K. Gruhot, Arushi Rai

  Colorectal cancer (CRC) will be the leading cause of cancer-related deaths for people under the age of 50 by 2030. Due to increased efforts to spread awareness for regular screenings, the five-year relative survival rate for those diagnosed with colon cancer is 64.4% (www.fightcolorectalcancer.org). Treatment for CRC consists primarily of the excision of the tumor paired with regular doses of chemotherapy and radiation therapy. These treatments cause systemic stress, damaging both cancerous and healthy cells alike. In order to create more efficient treatments, first, we must better understand the biology underlying changes in cells that lead to tumors in the colon. The proposed research aims to generate a better understanding of CRC using genetic models in Drosophila. We will specifically study the roles of the Hippo, Wnt, and JNK pathways on tumor formation and metastases in the colon. In order to do this, we have designed one- and three-hit models that disrupt each pathway singly and in combination with each other. These models represent the genetic heterogeneity in cancer patients, as well as represent the three most frequently found genetic lesions (p53, Ras, and APC.). The CRC models in flies will generate patches of cancerous cells in the fly gut (intestine). We will evaluate the CRC models (a) using antibody staining to check pathway activity (JNK, Wg, Hippo) and (b) using antibody staining to determine levels of proliferation and cell death. Overall, our studies will provide a platform for evaluating the effects of the three common genetic lesions in CRC and add to our knowledge about the altered communication between these oncogenes and pathways in CRC.

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  How We Free Ourselves: Freedom and Motherhood in Political Philosophy

  Aila Alene Carr-Chellman

  This project will further seek to understand the connections between feminism and other sociophilisophical traditions that explore liberation, such as colonialism, neoliberalism, patriarchy, and misogynoir. De Beauvoir in The Second Sex provides that the existential situation of women is different than that of men. I would add that the material situation of women can contribute to forming the fabric of freedom. Either by nurture or nature, we have a social situation wherein the oppression of people – the control and domination over people of many identities - is necessary for the world to function properly. What alternative story of history, or society, could be told when the structure of our world is no longer patriarchal? Competitive? Dominating? Or rigidly individualistic? The traditions of Marxism, radical feminism, anti-racism, anti-colonialism, and care ethic may hold a few of the answers to this question. My project seeks to draw upon the liberatory traditions of Marxism, anarchism, and feminism to reconsider our contemporary class context through the eyes of women. This project is to understand more deeply how a traditionally masculine project of control and domination perpetuates systemic disconnection, exploitation, and eventually the backwards movement of civilization. In doing so, I seek out the difference between men and women in how we free ourselves, and the pieces of freedom that man’s existential and ethical story has overlooked.

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  Identifying the effects of environmental conditions on L. monocytogenes fitness and pathogenesis modified by transcription factor CodY

  Elizabeth K. Herr

  L. monocytogenes is a pathogen with the capability of causing severe illness in individuals who consume contaminated foods. Many foods have been found to harbor the bacterium, but dairy products, produce, and other prepackaged foods are particularly susceptible to contamination. Contaminated foods are exposed to a variety of environmental conditions during packaging, processing, consumption, and digestion, all of which play an essential role in modulating the survival and pathogenesis of L. monocytogenes. Conditions of particular interest include cold storage, presence of food additives, and activity of antimicrobial enzymes such as lysozyme. My honors thesis research has focused on elucidating how L. monocytogenes fitness is regulated by these and other conditions and how the transcription factor CodY is involved in these processes. Most notably, our results suggest that CodY is involved in L. monocytogenes susceptibility to lysozyme. Our findings contribute to our understanding of how this dangerous pathogen responds to conditions relevant during transmission and infection.

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  Improving Methods for Enantioselective Organophosphorus Synthesis by A Chiral Nucleophile-Metal Bifunctional Catalytic System

  Jackson Thomas Shuman

  The use of Benzotetramisole (BTM) as a catalyst is a promising strategy for enantioselective organophosphorus synthesis since the reaction has been previously reported by Numan and Brichacek and has been tested in Dr. Erb’s research laboratory. However, the yields are only moderate (46-58%) and the enantiomeric excess (ee) of the purified product are poor, with 62% being the highest reported ee [1]. Preliminary computational data performed in the Erb lab has revealed that the cause of the lower ee (and possibly yield) could be the ability of the intermediate to adopt different conformations that are similar in energy but would give a mixture of chirality in the product. The addition of a metal ion could result in the formation of a ring structure, providing a firm anchor that prevents rotation of the Phosphorus-Nitrogen bond, and thus would form two possible intermediates. Locking the rotation of the intermediate prevents the relief of steric strain between groups on the substrate and the organocatalyst in one conformation, thus making one intermediate much higher in energy, less stable, and less likely to form. The other intermediate would also be locked in place in a similar way but has lower steric strain and thus would be more favorable. It may even be possible that the higher energy intermediate can isomerize to form the lower energy intermediate. Following this, bimolecular substitution by a nucleophile, such as an alcohol, would release of the catalyst and provide the product in improved enantioselectivity or yield.

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  Investigating the Theory-Practice Gap in Sales Engineering Transitions

  Jack Kenneth Doll

  This research paper reports the investigation of the theory-practice gap that exists for engineering graduates transitioning into sales engineering or technical sales roles. Sales engineering is the practice of employing technical knowledge to facilitate the sales process of complex engineered products and services, acting as a bridge between engineers and customers. A balance of technical knowledge and sales acumen are critical to success in these positions . To investigate this theory-practice gap, the researcher employs a mixed-method design consisting of self-assessment surveys directed at current and previous sales engineers to gauge their readiness and skills at graduation versus the skills they have acquired throughout their career. These surveys explore the aspects of missing skills, if any, that they have observed in their industry experience. This research provides valuable insights for educators, industry professionals, and aspiring sales engineers, facilitating a more seamless integration of theory and practice in this growing field.

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  Lovecraft and the Uncanny: A Psychoanalytic Critique of H.P. Lovecrafts' The Outsider

  Jules Carr-Chellman

  Scholarship on H.P. Lovecraft’s literature often will erroneously label his work as simply grotesque or weird. In this paper, I will use a psychoanalytical lens to critically examine Lovecraftian literature and argue that his fiction is not merely grotesque, but instead that his work displays elements of the uncanny that are ciphered in with more intentionally weird parts of his narrative. The first objective of this project is to define the uncanny as it is understood by Sigmund Freud: a feeling that occurs when something that is meant to be hidden is revealed. Having established Freud’s psychoanalytical framework of the uncanny, I will then apply it to H.P. Lovecraft's short story The Outsider.

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  Membrane-Level Experiments: Validation Testing for Dielectric Elastomer Actuators

  Nathan Benham

  Nonlinear Dynamics of Soft Electro-Active Materials Under AC Voltages

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  Mucin Can Rescue Anaerobically Grown Listeria monocytogenes from Killing by Antimicrobial Peptide Ll-37

  Nicolina Valore

  Listeria monocytogenes is a foodborne pathogen that can cause infections with a high mortality rate in the United States. Therefore, learning more about the interactions between this pathogen and our immune defenses could greatly strengthen our ability to protect high-risk communities. During transmission from food to the human intestines, L. monocytogenes is exposed to various environmental conditions, including propionate, a common food additive as well as a fermentation product by our gut microbiota, and various oxygen levels. How these environmental factors influence L. monocytogenes fitness and pathogenesis is not fully understood. My Berry Summer Thesis Institute research investigated L. monocytogenes interactions with mucin and antimicrobial peptides, both are critical barriers found in the intestinal lumen. L. monocytogenes was grown with or without propionate under aerobic or anaerobic conditions and then exposed to mucin and antimicrobial peptides. Then, I measured the bacterial colony forming units (CFUs) to calculate survival after exposure. My preliminary results showed that anaerobically grown bacteria were more susceptible to antimicrobial peptide LL-37 than aerobically grown bacteria. However, the presence of mucin rescued anaerobic, but not aerobic, bacteria against LL-37. These results highlight the need to further investigate the role of oxygen in L. monocytogenes fitness and pathogenesis under relevant conditions.

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  Political Representation, Democracy, and the Electoral College: An Applied Theoretical Analysis

  Jordan A. Marsh

  Though a key institution in the United States presidential election, the Electoral College has often been overlooked for close theoretical analysis and even less frequently dissected for a deeper understanding of its consistency with theories of representative democracy. As such, this presentation summarizes a study of the Electoral College through a theoretical lens to ultimately investigate the degree to which it is democratically representative. The first section analyzes the Electoral College through both a historical and a modern contextual lens. The second section of this paper explores various theories of representation, including the works of Pitkin, Rehfeld, Manin, and Mansbridge, among others. The third section scrutinizes the Electoral College’s representative nature through the frameworks of these theorists. Finally, the fourth section brings the representative nature of the Electoral College in conversation with the ideals of representative democracy, making the case that the Electoral College, in its current form, lacks critical aspects of democratic representation.

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  Porous Materials as a Thermal Protection System for Hypersonic Flight Vehicles

  Megan Colleen Sieve

  Hypersonic flight is defined as speeds of Mach 5 and faster. A critical problem that arises at those speeds is the immense heating of the vehicle. Hypersonic vehicles have thermal protection systems (TPS) to aid in thermal regulation; however, as faster speeds require large TPS, a design concern is how to make the TPS so to not cause any harm to the vehicle’s performance. This research project will investigate the most prominent instability that causes turbulence, and consequently, heat, on a flat-plate at Mach numbers of 4 and above: the second-mode boundary-layer instability. Different porous materials have been shown to dampen acoustic waves, which are the cause of second-mode boundary layer instabilities and is the focus of this study. This project is a continuation of the study “Effect of Porosity on the Ability of Silicon-Carbide Foams to Attenuate the Second-Mode Boundary-Layer Instability” (Bemis et al.). Experimental techniques used were PCB pressure sensors, Schlieren imaging, infrared thermography, and Rayleigh scattering. Silicon-carbide porous foams, wavy wall samples, and impermeable samples were tested on two different sized flat plates. The goals of these experiments were to study boundary-layer transition and the effect that different porous materials had on the boundary-layer.

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  Quantitative Concentration and Density Measurements in Subsonic and Supersonic Helium Jets Using Rainbow Schlieren Deflectometry

  Henry H. Jacques

  Rainbow Schlieren Defectometry (RSD) has been applied to acquire quantitative concentration and density measurements in both subsonic and supersonic conditions. Experiments were conducted using a helium jet expelled into air for two distinct regimes: initially laminar, momentum-driven at subsonic speeds, and subsequently at supersonic speeds. Comprehensive full-field measurements were captured, encompassing the laminar, transition, and fully turbulent regions of the jet in both subsonic and supersonic conditions. The subsonic (momentum-driven) regime was validated against Rayleigh scattering data in the literature. The supersonic regime utilizes a novel approach for acquiring density, where the mixing field is delineated into three portions: the potential core, the non-isobaric mixing shear layer, and the isobaric far field. Results from the RSD technique demonstrate robust mixing measurement capabilities for both subsonic and supersonic applications. The results from this work show promise for future applications involving the use of quantitative RSD for fuel injection studies.

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  Quantitative Scalar Supersonic Boundary Layer Measurements on a Conical Geometry using Rainbow Schlieren Deflectometry

  Joseph Kastner

  This study utilizes an optically accessible shock tube to emulate supersonic flow conditions for the purpose of a novel optical diagnostic development. A simple conical cone is used to develop a methodology to acquire full-field, quantitative scalar measurements in the boundary layer via Rainbow Schlieren Deflectometry (RSD). RSD will be implemented for the first time to record quantitative full-field density and pressure measurements inside the boundary layer. A parametric study is performed to investigate the full-field evolution of the density and pressure fields under the effects of Mach number. The results of this study will be validated with pressure probe data gathered from within the shock tube.