Stander Symposium Projects

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  Cybersecurity at Fairborn Equipment Midwest

  Jonathan David Disidoro, Luke David Evankovich, Ella Rose Glabus, Megan Elizabeth Peters

  Our team will be analyzing security risks at Fairborn Equipment Midwest, and offering recommendations regarding the processes and software already in place. One of the deliverables will be documentation surrounding current practices and suggestions for improvement. The project may also include the implementation of new software, practices, or security measures if time allows. The goal of this project is to improve the cyber security of the organization, and decrease the risk of downtime or failures of critical business processes.

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  Dayton Children's Hospital

  Nathan Frank Bertuca, Ryan Frank Cendol, Wesley Dee Safford, Elizabeth Ann Wourms

  mplementing a resource planning model. This model will consist of resource capacity management, resource capacity forecasting, prioritization methods, and a display of where resources are currently being utilized. Dayton Children’s has two different systems to manage IT projects currently (FreshService and Workfront) that would need to be included in the model. These systems manage a range of IT issues spanning from small bug fixes to individual or departmental IT project work. Dayton Children’s main project objective is to discover where their resources are actively being used and when these resources will be available to use for future projects. Microsoft products including the Power Platform will be used to implement this system.

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  Dayton Civic Scholars & Gem City Market

  Rose C. Arkus, Charles Kenneth Baker, Lilianna Jin Biswas, Madeline Elise Calhoun, Benjamin Joseph Crawford, Lauren Elizabeth Durham, Ryan David Greensfelder, Kate Mulvihill Jones, Meghan Elizabeth Leinhauser, Larissa Anne O'Shea, Grace Julia Pigman, Erin Marie Rafter, Jada Lynn Smith

  The Dayton Civic Scholars 2022 cohort is excited to share our capstone project and our journey despite pandemic challenges. As a cohort we are passionate about sustainable and meaningful engagement opportunities, and identify the Gem City Market as an important asset to our community, both on and off campus. Since Spring 2021 we’ve partnered with the GCM and focused our time, energy, and resources on the market in hopes of supporting their work in the community. Our cohort explored ways to engage with the community through GCM and worked together on marketing, transportation, and programming initiatives. We believe the University of Dayton can continue to support and benefit from GCM and are excited to share our journey and accomplishments throughout the past year of engaging with the community and the market.

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  Department of History Major Capstone Projects

  Hallie M. Bergmann, Matthew James Frabotta, Eshaan Garst N. Garst, Samuel Christian Johnson, John R. Lally, Thomas Jacob Martin, Jackson Fryer Prieto, Sebastian M. Quinones, Katherine Elizabeth Smith, Nicholas Jordan Torchio, Lindsey E. Vanhoose

  Capstone presentations by History Department Seniors showcasing scholarly historical projects based on primary source analysis and historiographical context. Topics range from Post-War Japanese reconstruction, The Nature of Violence in colonial Hispaniola, Communism and Catholicism, Medieval ideals of gender, The Western Schism, Argentinian Politics under Juan Peron, Theater and Politics, Italian immigration, women in Colonial Latin America, Theater and politics, Drugs and Prohibition in twentieth century USA.All are welcome!

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  Department of Music Honors Recital Auditions

  Amanda Bursch, Anna Delaney, Teresa Grijalva, Trinity Hines-Anthony, Camryn Horning, Emily Hunt, Angelo Moore-Knight, Emily Lewis, Declan Phelps, Daniel Sheldon, Anna Simmons, Anna Smith

  Each year, UD Department of Music faculty select top student performers from the Department’s Friday Recital season and invites them to audition before a panel of preeminent musicians from the Dayton community. The top six performers are awarded a position on the Department of Music Honors Recital, the culminating performance of the academic year, held at 1:25 pm on April 29. 2022 in the Humanities Building’s Sears Recital Hall. Both the auditions and the Honors Recital itself are open to students, faculty and members of the community.

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  Design and Validation of a Liquid-Liquid Extraction Unit Operation Experiment

  Zoe R. Boehman, Austin G. Dias, Luke F. Flottman, Katelyn Leigh Petrycki

  Liquid-liquid extraction (LLE) is a separation technique that transfers a solute between two immiscible solvents. The separation of ethanol through LLE is prevalent in biomass purification, gas additives, and the food safety industries. This research aims to generate a new experiment involving LLE processes in the Unit Operations laboratory at UD. Castor oil served as the organic phase to separate ethanol from water due to their differences in miscibility. The effectiveness of castor oil was measured using a mixer-settler unit (~ 2 L) with a 5 wt.% ethanol/water mixture. Volumetric ratios of castor oil to ethanol, such as 6:4, 5:5, and 7:3, were pumped, mixed, and run in the mixer-settler apparatus. At various time intervals, samples were taken from oil and aqueous phases, centrifuged, and analyzed using gas chromatography or a densitometer. Extracted samples did not reach equilibrium, and a discrepancy existed between the experimental results and the theoretical model found using a ternary diagram. Additional trials involving an extra settling chamber showed that longer mixing-settling times led to enhanced ethanol extraction. Centrifugation, however, was needed to separate the two phases. A second organic solvent, Multitherm heat transfer fluid, separates from the aqueous phase faster than castor oil. We performed small-scale experiments (10 mL) at different ratios of Multitherm to 5 wt.% ethanol/water solutions, such as 1:1, 6:4, 7:3, 8:2, 9:1, and 2:8. The 2:8 mixture showed enhanced separation based on ethanol concentration in the aqueous phase. Conversely, 2:8 mixtures of 5 wt.% ethanol/oil solution to water were mixed and analyzed. Unfortunately, ethanol stayed immiscible with the oil, and the water phase only removed 1.2 wt.% ethanol. The new mixture was targeted for ease of phase separation when running the mixer-settler unit, and the preliminary trials allowed for pursuing experimentation for a closed system mixer-settler unit.

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  Design of an Investment Ready Solar Energy, Bitcoin Mining, & Water Purification Package for Equity Expansion in the Navajo Nation

  Matt Abele, Abin Johny

  Although the world lives in the 21st century, inequality, poverty, hunger, and thirst plague many parts of the world. While developing nations receive a vast majority of the attention and aid, there are communities closer to home which should garner greater publicity than they currently receive. In the United States alone, large populations of people live without access to running water, let alone potable water for consumption, cooking, and general hygiene. For centuries, Native American populations have endured hardship and suffering at the hands of the American people and government, who seem to have all but forgotten their existence. In the Navajo Nation, the largest reservation in the United States, as many as 30 percent of residents lack access to running water and many lack sufficient access to potable drinking water. Compounding these issues are the great distances they must travel for food and water, placing even greater economic strain on the people. This project serves to elevate marginalized communities, like the Navajo Nation, by providing for the most essential needs of the community while also providing some monetary benefit – increasing equity and elevating the people. The developed micro-grid design includes a solar array and battery storage sized to provide power year-round to the bitcoin farm while also providing power for a water purification system capable of meeting the needs of the community. This investment-ready package provides community income in the form of bitcoin, while also providing clean drinking water from unregulated wells which otherwise supply the area with contaminated water. Income from the bitcoin mining operation goes to a community fund while also paying back investors in a short time making this an attractive project for investors and communities alike. Further adaptation could be implemented to provide for other community needs such as indoor farms or community electrical loads.

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  Design of a Soft Robot Pneumatic Cushion for Bedsore Prevention in Persons with Paraplegia or Tetraplegia

  John M. Wischmeyer

  The University of Dayton Design of Innovative Machines Lab (DIMLab) is working in the area of soft robot design. In prior work, the DIMLab has investigated accurate CAD modeling of the PneuNet actuator, proposed by the Whitesides Research Group of Harvard University. PneuNet actuators are mainly used as soft robotic grippers capable of readily moving fragile or asymmetrical objects. The DIMLab has started to explore the use of soft robotics in a variety of fields, from medical to manufacturing. One potential novel application of soft robotic technology is in the prevention of pressure ulcers. Persons with para- or tetraplegia, and many of our elderly, are more likely to develop pressure ulcers from being in a seated position for longer periods of time. An assistive device that can safely and automatically mitigate pressure ulcer formation is clearly desirable. This honors thesis will explore the design and prototyping of the “Derri-Air” pneumatic cushion, capable of sensing and altering the pressure distribution applied to the user’s buttocks. Be it noted that the honors thesis will not require human test subjects from outside the University of Dayton. When a functioning model of the Derri-Air cushion is developed, only students working for the DIMLab will test the device for comfort and compatibility. An important step in achieving a working prototype is preliminary research into the continued development of PneuNet-like bending actuators, including their design, simulation, printing, and testing.

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  Design of Custom Mechanical Test Fixtures for Uniaxial Compression and Pure Shear Testing of Soft Materials

  Braeden J. Windham

  SURE program work focused on implementing a photo-curable elastomeric resin on commercially available 3d printers, creating an in-situ monitoring system to collect unavailable print data, creating custom fixtures for the characterization of elastomeric materials, characterizing the mechanics of a DLP printed, self healing, elastomeric resin.

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  Determining Nitrate Sources Using Dual Nitrate Isotopes in Grand Lake St. Marys Watershed, Ohio

  Maria Isabel Schutte

  Grand Lake St. Marys, one of the largest lakes in Ohio, regularly experiences harmful algae blooms that disrupt access to drinking water and recreation. The Grand Lake St. Marys watershed, designated as a distressed watershed since 2011, is one of the most nutrient impacted lakes in Ohio with pollutants potentially originating from anthropogenic sources including organic and inorganic fertilizers, human wastes, and urban runoff. The eutrophication of the lake is in part caused by an excess of nitrate, which can come from these sources. The aim of this study is to identify and quantify the relative contributions of these anthropogenic sources of nitrate in the Grand Lake St. Marys watershed to better inform nutrient management decisions. We collected field environmental data and 43 water samples from the lake and all streams in the six sub-basins of the watershed. Samples were analyzed for nitrate concentration and isotope ratios of nitrogen and oxygen in nitrates. Dual isotope tracing of nitrate (δ15N and δ18O) allows us to determine nitrate sources based on isotope end-member values from those sources. But as δ15N of human and animal waste overlaps, further analysis of boron isotopes (δ11B) is used to distinguish anthropogenic sources from natural sources. Our results indicate that the main source of nitrate in this watershed is manure, which contributed 77-100% of all nitrate sources in the watershed. Although denitrification could increase the δ15N and δ18O values of nitrate and overlap with manure, based on high level of measured dissolved oxygen (DO) in the field and slope of δ15N and δ18O values, we were able to rule out this process. This research provides an initial nitrate contaminant source tracing data and helps to better inform state and local water quality and nutrient management planning.

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  Determining the association between gut microbiota and its metabolites with higher intestinal Immunoglobulin A response

  Tooba Shafeeque Ahmed Momin, Adam D. Moorman, Jessica Marie Sheldon

  The gastrointestinal (GI) tract harbors an enormous amount of complex microbiota community and the GI-immune system is one of the largest immune organs in the body. Gut microbiota influences gut health and affects local and systemic immune response. The current study was designed to determine the specific gut microbiota and its metabolites responsible for higher intestinal immunoglobulin A (IgA) concentration. Twenty piglets (Scrofa domesticus) with an equal number of males and females were used in the study at one-week post-weaning. Fecal samples from these piglets were collected in sterile test tubes and analyzed for IgA concentration while part of the samples was stored at -80 °C for later analysis. Based on IgA concentration, piglets were divided into two groups, group 1 with lower IgA concentration (< 2.0 µg IgA/gram of feces) and group 2 with higher IgA concentration (>2.0 µg IgA/gram of feces). These groups were then analyzed for their differences in microbial metabolites and microbiota community using 16S ribosomal RNA gene sequencing. Results indicated that higher IgA concentration was associated with significantly higher Bacteroidota and Desulfobacterota population and significantly lower Firmicutes and Firmicutes/ Bacteroidota ratio (p <0.05). Results also indicated that higher IgA was associated with low acetic acid, butyric acid, formic acid, isovaleric acid, and propionic acid. All these short-chain fatty acids have shown their effectiveness in reducing gut inflammation. Higher IgA was directly related to higher valeric acid concentration. Piglets with higher IgA also had significantly higher xylulose, tocopherol-alpha, glycine, adenine, pantothenic acid, xylitol, pimelic acid, palmitic acid, and alanine concentration in the gut (p<0.05). Higher IgA was associated with significantly lower tyramine, putrescine, phytosphingosine, beta-alanine, 4-aminobutyric acid concentration (p<0.05). Overall, the current study indicated that higher gut IgA had a direct relationship with lower Firmicutes/ Bacteroidota ratio and lower short-chain fatty acids.

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  Development of Melamine Derivatives as Flame Retardants for Thermoplastic and Thermoset Polymers

  Ryan J. Maguire

  Melamine is an aromatic, nitrogen-containing compound used to produce a myriad of items ranging from kitchenware to laminate. This project focused on the investigation of pathways to prepare melamine derivatives, which could function as potential reactive flame retardants. For that purpose, a set of bifunctional derivatives was prepared and characterized. Attempts to involve these compounds as co-monomers in the preparation of Nylon-type polymers is currently being studied.

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  DHL- Supply Chain Locus (Robots) Goes Green

  Brandon Richard Barhorst, Christian J. O'Connor, Kendall S. Schaffner, Allison M. Vanzant

  This project researches various opportunities to make the use of the warehouses picking robots more sustainable and supportive of the environment

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  Diabetes in Dayton, OH: a Focus on Free Healthcare Clinics

  Griffin Andrew Kirsch, Audrey Elizabeth Muck

  In less than a decade, the State of Ohio increased in rank from 19th to 13th in the United States of America for diabetes prevalence, according to a 2020 statistic from the Behavioral Risk Factor Surveillance System (https://stateofchildhoodobesity.org/). The average diabetes prevalence rate in the United States is estimated to be 10.5%, whereas the prevalence rate for diabetes in Montgomery County is 13.6% (CDC, 2016-2017). This prevalence is well above national, state, and other surrounding county averages, and is also coupled with extreme racial data discrepancies. The diabetes mortality rate among black men is nearly two times the rate of other races in Montgomery County; furthermore, the rate of diabetes-related hospital visits is 1.5 times higher for black individuals than white individuals, according to the Greater Dayton Area Hospital Association Healthcare Database (2018). In addition, racial and ethnic minority populations have a higher percentage of adults, adolescents, and children diagnosed with diabetes and are more likely to have poorer management of diabetes. An approach to preventing the progression of diabetes and decreasing mortality and hospital visit rates includes prioritizing and providing information and skills for people to manage their diabetes and related conditions at local health clinics that treat individuals at target risk. This approach includes a program known as the Diabetes SelfManagement Education and Support (DSMES) which yields effective results in managing diabetes (CDC, 2018). As a result of this approach, the mortality rate is declining. This poster will describe the prevalence of diabetes in Montgomery County, highlight racial disparities, review relevant social determinants of health, and discuss how a community can improve the outcomes of diabetes.

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  Differences in leaf litter rates in forests: Lateral vs. vertical input of leaf litter into a broadleaf forest river

  Rianna Soltis, Amanda N. Thieneman, Valerie Nicole Thurston

  Leaf litter is the collection of leaves that fall from the surrounding trees in an ecosystem. The leaves decompose in the spot they fall or where they get carried away towards water. Leaf litter data showcases the biodiversity in an area, which can help identify if the area is healthy or not. We also thought it important to see how much of this leaf litter is ending up in the river. In our experiment, we wanted to look at the difference between leaves that were collected vertically versus laterally in the oxbow river. Vertical litter is what falls off the tree, in our case, over the water. This can be caused by wind or by naturally falling off. The lateral litter we are looking at refers to the leaves that are not falling directly into the river by tree fall. They fall more inland and are carried by water from rain or wind into the river. We wanted to see the difference between the two types of leaf litter collection. The study site, Old River Park, was once a manicured park for employees but now it belongs to the University of Dayton. It is partially maintained by mowing, but a portion of it has been designated as a research area and has become an area with little to no upkeep and has become overgrown. This is the area of the park that we conducted our research in. The oxbow is partially shaded by broadleaf deciduous trees, like American Sycamore (Platanus occidentalis) and White Ash (Fraxinus americana). At the site of the oxbow where we studied the input of leaf litter, there was a mix of larger trees like Sycamore, but there was also a large presence of the invasive Honeysuckle tree (Lonicera maackii). Because of the density of trees surrounding the river, compared to the density of trees reaching over top the river, we hypothesized that the leaf litter from entering the river laterally would be greater than the leaf litter entering the river vertically.

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  Direct polymerization of aliphatic bis-piperazine compounds and their non-antimicrobial properties

  Emilie A. Moses

  The piperazine functional group has found applications in the structure of novel antidepressants, chemotherapeutics, stimulants, and more recently as antimicrobial agents. Inclusion of piperazine in a material also leads to the chelation of metals (including toxic metals), which would have several environmental applications as fiber mats or bioengineering scaffolding materials. Thus, we synthesized the first aliphatic polyester polypiperazines directly from the Ti(IV) condensation of 1,4-bis(1-hexanol)piperazine with succinic acid. We characterized these novel polymeric materials using NMR, IR, and gel permeation chromatography. Since the biodegradation of these polymeric materials could lead to the release of a toxic by-product (the bis piperazine compounds), we analyzed the antimicrobial activities of the diol using AG100 E. coli as planktonic cultures (using the starting bis alcohols). We determined the antimicrobial activities using growth inhibition assays (with and without levofloxacin) as well as live/dead fluorescence staining of planktonic cells. We compared our growth inhibition results to 1-napthylmethylpiperazine and napthylmethylpiperazine derivatives. These collective data suggest polyester polypiperazines could be a novel thermoplastic, bioinert, biodegradable scaffolding material for tissue engineering and environmental applications.

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  Does a Required Nutritional Education Course Improve Overall Health in Undergraduate Students?

  Alexys N. Kidd, Gillian Losey, Clayton Richard Mathile

  The objective of this study is to investigate the nutritional knowledge of undergraduate students at the University of Dayton and how it affects their overall health. The study will be conducted through a survey that will be sent to undergraduate students at the University of Dayton. The participants will receive an electronic consent form and survey that contains questions about nutritional knowledge and personal prioritization of nutrition. Analyzed data will be used to answer questions like if a nutrition CAP requirement would be beneficial to students in college. The survey will be completed through a Google Form that will make it fluid for the researchers to quickly formulate the survey as well as distribute it to students in a timely manner. The questions that will be utilized in this study are to allow the researchers a better understanding of what undergraduate students at the University of Dayton know about the subject of nutrition. Ultimately, this study will show if there is a need for a nutrition curriculum to be added to course requirements. Data collection and results are forthcoming.

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  Does the Level of Caffeine Intake Relate to the Risk of Developing the Signs and Symptoms of Anxiety in College-aged Students?

  Laurel Catherine Bird, Brandon James Christopher, Haley Kate Gama, Marie A. Gross, Madeline Sarah Nichol

  Background: Caffeine consumption is common among college students for various reasons such as increasing studying time or partying situations. The consistent use of caffeine has been found to elicit the “fight or flight” response in the body which causes stress and can stimulate anxiety. This research investigates whether caffeine use is related to the signs and symptoms of anxiety in college students.

  Purpose: The purpose of this study is to determine the relationship between caffeine consumption and signs and symptoms of anxiety in college students.

  Methods: Methods include the collection of data on caffeine intake and the signs and symptoms of anxiety. This information will be obtained via a self-report survey to college students at the University of Dayton to gauge what their caffeine intake habits are and what their levels of anxiety are during a typical two week period. Questions will be formulated based on GAD-7 for the anxiety portion of the survey. Additional questions about caffeine were formulated by the researchers based on previous studies and inquiries.

  Results: Data collection occurred March 28-April 4. Results are forthcoming.

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  Drinking Culture on College Campuses: A Look Into Why It Is So Prevalent

  Christine Ann Grimes

  Drinking culture at college campuses and universities is a serious problem among students. Students drink for various reasons which can be controlled by students’ choices or peers. Four subsets are researched as to why drinking culture is so prevalent and some factors that play a role in this behavior. Four variables relating to student life in college were: residential locations, mental health issues, student athletes and peer pressure. Scholarly journals were selected to research these variables as they relate to drinking culture. Secondary data were analyzed from The Healthy Minds Study relating to alcohol use and consequences. There are many factors that cross over the four categories researched and the state of one's mental health is common to all four.

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  Drosophila eye model to study the role of NAT9 in Alzheimer’s Disease related Dementia (ADRD)

  Prajakta D. Deshpande, Emily M. Snider

  Alzheimer's Disease (AD), an age-related progressive form of dementia, is characterized by a decline in cognitive function. Accumulation of amyloid beta (Aβ42) plaques is one of the characteristics of AD. The accumulation of these Aβ42 plaques trigger the hyperphosphorylation of tau, a microtubule associated protein, which results in the intracellular accumulation of neurofibrillary tangles (NFTs) due to destabilization of microtubules. We employed the Gal4/UAS system in Drosophila melanogaster to misexpress human Aβ42 within the developing fly retina, exhibiting AD-like neuropathology. Accumulation of Aβ42 plaque(s) triggers the aberrant activation of signaling pathways like the JNK pathway resulting in neuronal cell death by unknown mechanism(s). Using candidate based forward genetic screening, we identified N-acetyltransferase 9 (NAT9) as one of the genetic modifiers of GMR>Aβ42 reduced eye phenotype. Previously NAT9 has been shown to stabilize microtubules by acetylation of tubulins, thereby inhibiting JNK signaling. This study aims to understand the role of NAT9 in Aβ42-mediated neurodegeneration. The gain-of-function of NAT9 in GMR>Aβ42 background suppresses the Aβ42-mediated neurodegeneration whereas loss-of-function of NAT9 in GMR>Aβ42 background enhances Aβ42-mediated neurodegeneration. We have also found that the gain-of-function of human NAT9 also suppresses Aβ42-mediated neurodegeneration suggesting the functional conservation. Interestingly, mutated NAT9 in the acetyl- CoA binding site shows similar phenotype as gain-of-function of NAT9 suggesting its function is independent of acetylation activity. Moreover, the eye antennal imaginal discs of loss-of-function of NAT9 in GMR>Aβ42 background shows the activation of JNK pathway by increased pJNK levels. Hence, here we propose that NAT9 downregulates JNK signaling pathway which can ameliorate Aβ42-mediated neurodegeneration.

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  Effect of COVID-19 on mental health resources and symptom prevalence

  Shannon Patricia Camardese, Elli Jeannette Ertl, Paige Marie Kompa

  Crisis Text Line provides a free, 24/7 text-based mental health support and crisis intervention composed of trained volunteers. In 2020, 1.4 million interactions between the counselors and texters were exchanged, supporting 843,982 texters. This totaled to more than 48 million messages (Crisis Text Line, 2020). Data was collected by Crisis Text Line through 2019 and 2020 focusing on COVID-19 pandemic's most severe stages. Additional data was obtained through a local partner, University of Dayton's Counseling Center. In the fall of 2021, 2,890 UD students were seen in a clinical appointment setting; due to the overwhelming need for broader access, the Counseling Center added brief consultations, called “Let’s Talk Sessions”, allowing 240 more students to be seen in their time of need. Overall, 28.5% of UD students seen by the Counseling Center reported symptoms of depression and 52.8% reported excessive anxiety (University of Dayton Counseling Center, 2021). These results mirror those of Crisis Text Line that reported depression and anxiety as the top issues texters struggle with. This trend is also seen in the interactions of a crisis counselor. In conversations of one Crisis Text Line counselor (Paige Kompa) dating from April 2020 to present, 26.2% of texters reported experiencing anxiety and 35.0% dealt with depression (2022). The experiences of Americans and UD students alike show the vast impact of COVID-19 on mental health and demonstrates the need for mental health resources. This poster aims to discuss the effects of the pandemic on mental health and highlight what has been done to address the issue.

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  Effects and Prevalence of Depression and Anxiety on University of Dayton Upperclassmen Students

  Charles Vincent Bova, Catherine Aleta Fay, Grace Elizabeth Lewis

  The purpose of this study is to determine how upperclassmen at the University of Dayton develop depression and anxiety. This study aims to discover the prevalence of depression and anxiety amongst junior and senior undergraduate students, and what symptoms they predominantly exhibit. A thirteen-question survey will be distributed to each researcher's neighborhood block group chat. Participation will be confidential anonymous. Participants will only need to indicate their grade level to ensure all participants met the age criteria of third or fourth years at the University of Dayton. Data collection and result analysis will be occurring between March 22 and April 4.

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  Effects of Deposition Temperature, External Magnetic Field, and Annealing for Magnetron Sputtering Deposition of Bi4Se3 Thin Films

  Tobin C. Muratore

  Recently, bismuth chalcogenides have been of interest as topological insulators, especially for their potential use in polarized light detecting and other devices. In particular, Bi4Se3 presents a topologically insulating material which contains a native heterostructure of Bi2Se3 and Bi2 layers, each with its own topological state. In spite of these valuable properties, the growth of Bi4Se3 via magnetron sputtering remains less studied. This study elaborates the properties of Bi4Se3 films grown in a magnetron sputtering system with an external magnetic field. Numerous films were grown on heated sapphire substrates with different deposition temperatures, external magnetic field orientations, and annealing procedures. These films were characterized via X-ray diffraction (XRD), and the X-ray results were analyzed to determine crystallite size. This characterization indicates the role of temperature in determining whether the deposition produces an amorphous, polycrystalline, or primarily basally oriented film. In addition to XRD, some films were characterized by Angle-Resolved Photoemission Spectroscopy to observe the variation in electrical properties in the amorphous, polycrystalline, and basally-oriented films. Results display a clear effect of external field orientation on film microstructure. Additionally, annealing appears to effect microstructure as well and demonstrates a clear ordering effect on the films.

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  Effects of the United States foster care system on juvenile delinquency

  Olivia Watson

  The United States foster care system was home to nearly 500,000 children in 2019. The link between the United States foster care system and juvenile delinquency is empirically under-explored and theoretically under-examined. Using data collected from the Pathways to Desistance study, the current study examines the relationships between drug and alcohol abuse, exposure to violence, and early onset behaviors with those who have been in the foster care system. Using a linear regression for the statistical analysis, findings show a significant association between exposure to violence and the foster care system. While there is no significant association between drug and alcohol abuse or early onset behaviors and the foster care system, the findings suggest a trend toward a positive relationship.

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  Electrically Injected GeSn Lasers towards Room Temperature

  Nicholas Saunders

  Use of group IV materials for semiconductors offers many benefits compared to traditional group III-V materials. Germanium tin (GeSn) in particular has a direct bandgap above 8% Sn composition, making it ideal for use in optoelectronic devices. GeSn is also complementary metal-oxide-semiconductor (CMOS) compatible and has potential applications in infrared imaging and light detection and ranging (LIDAR) technology. However, electrically injected GeSn lasers have not yet been extensively researched. The operating temperatures for such devices are low, with the world record highest temperature at 110 K. Higher operating temperatures are desired to increase use in applications. A PIN-doped GeSn wafer was prepared by chemical vapor deposition (CVD) and wet etching. Electrodes were deposited and wire bonded to an Si carrier chip to form a PIN-diode. The sample was electrically injected using a pulsed voltage source. The electroluminescence (EL) spectra and light output versus current (LI) curves were measured. The device successfully lased with a wavelength of 2688 nm at the maximum temperature of 135 K. This beat the previous world record operating temperature by 25 K. The threshold current density was 701 A/cm2 at 77 K and 2813 A/cm2 at 135 K. Alterations in material growth and device structure need to be studied in order to further increase operating temperature to room temperature.