Undergraduate Senior Theses

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A senior thesis is a paper which highly-motivated senior undergraduates may write to present the results of a major, independent research or creative project. Unlike most term projects, papers, and lab reports written in undergraduate courses, a senior thesis addresses questions or issues for which no known or generally accepted answers exist.

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Alcohol Exposure During the Brain Growth Spurt Alters Medial Prefrontal Cortex Hippocampus Functional Connectivity During a Spatial Working Memory Task
(University of Delaware, 2023-05) Rosenblum, Hailey
The brain growth spurt is a period of rapid brain growth and development which occurs during the third trimester of human pregnancy and the first two postnatal weeks in rodents. The hippocampus and medial prefrontal cortex (mPFC), structures which are important for spatial working memory, are vulnerable to alcohol exposure (AE) during the brain growth spurt. The nucleus reuniens (RE) of the thalamus has been demonstrated to play a role in orchestrating mPFC-hippocampus interactions which are necessary for spatial working memory. The RE has also been shown to be damaged due to AE in a third trimester rodent model. Recently, our lab has shown that rats exposed to alcohol during the brain growth spurt display spatial working memory impairments. The current study examines mPFC-hippocampus theta synchrony to determine if these effects can be explained by altered functional connectivity between these regions. In this study we measured mPFC-hippocampus theta coherence, a metric that describes the degree to which mPFC-hippocampus theta rhythms are temporally correlated. We hypothesized that rats exposed to alcohol during the brain growth spurt would show reduced mPFC-hippocampus theta synchrony compared to sham intubated (SI) rats during decision making. Specifically, we predicted that AE rats would show reduced theta coherence at the choice point of a T-maze as they performed a spatial working memory task. To study our hypothesis, pups were administered 5.25 g/kg/day alcohol via intragastric intubation between postnatal days 4-9. The sham intubated (SI) group received intubation without alcohol. Once rats reached adulthood (postnatal day 90), they completed pre-training in a T-maze to become familiarized with the testing environment. Rats then underwent local field potential (LFP) electrode implantation surgery, during which stainless steel wires were implanted into the mPFC and hippocampus. Once recovered from surgery, rats were trained on the continuous alternation (CA) task, which is not a hippocampus dependent task but allowed rats to learn the alternation rule. Upon reaching the choice accuracy criterion of 80% for two consecutive days, rats learned the spatial working memory-dependent delayed alternation (DA) task. Each DA session consisted of 10 second, 30 second, and 60 second delay trials, with 12 trials of each delay length in a pseudorandom sequence. LFPs were recorded as rats performed the task. We then analyzed mPFC-hippocampus theta synchrony at the choice point of the T maze. In support of our hypothesis that AE during the brain growth spurt reduces mPFC hippocampus theta synchrony, we found that DA task recording sessions of AE rats showed lower mPFC-hippocampus theta coherence when rats occupied the maze choice point compared to sessions of SI rats. Neural activity within brain regions was also altered, as hippocampus theta power was increased in sessions from AE rats compared to sessions from SI rats. These findings can help explain our previous finding of impaired spatial working memory in AE rodents. This study is important because it contributes to filling the gap in knowledge of how developmental AE affects cognitive function and the underlying mechanisms later in life.
CLASSICS, ORIENTAL STUDIES, AND THE CONSTRUCTION OF AMERICA’S WESTERN IDENTITY, 1865–1930
(University of Delaware, 2023-05) Wagner, Kelsey
The American education system changed drastically between the end of the Civil War in 1865 and the interwar period up to 1930. In the years leading up to the Civil War, institutions of higher education adhered to the classical curriculum, which promoted the study of ancient Greek and Latin for the development of moral citizens. In the face of industrialization and professionalization that came with the late nineteenth century, the classical curriculum lost value and fell by the wayside. Colleges and universities instead turned to the sciences and vocational fields such as engineering and agriculture. This professional and scientific turn provoked great changes in the field of classics so that it acquiesced to the data-driven methodologies of the newly formed social sciences. Accompanied by its novel sister discipline, Oriental studies, the social-scientific study of classics began to divorce the field from religion and the Biblical chronology while adhering to the social evolutionary model. The revitalized field of classics and Oriental studies gained prevalence in the inter-war period as America found itself a global power. This thesis explores the archives of five major universities as well as scholarship published in classics and Oriental studies between 1865 and 1930 to construct a narrative of the emergence of “Western civilization” and a solidified East-West binary in American thought.
VALLEY SPLITTING AND MAGNON-EXCITON COUPLING IN TRANSITION METAL DICHALCOGENIDES USING SEMICONDUCTING ANTIFERROMAGNETS
(University of Delaware, 2023-05) Whalen, Matthew
Valleytronics presents an innovative approach to the storage and manipulation of binary and quantum information. The availability of 2D materials has opened up exciting possibilities for exploring Valleytronics in transition metal dichalcogenides (TMDCs), owing to their valley-contrasting orbital magnetic moments and optical selection rules. While the selective control of K and K' valleys in TMDCs can be achieved by lifting the valley degeneracy using an external magnetic field, this approach has proven impractical due to the weak Zeeman splitting. Fortunately, the magnetic proximity effect obtained by interfacing a TMDC with a ferromagnet offers a solution that lifts the valley degeneracy even further. However, the realization of valley splitting via the magnetic proximity effect induced by a semiconducting antiferromagnet (AFM) has remained elusive. In addition, simultaneously establishing magnon-exciton coupling in a heterostructure of an AFM and TMDC while breaking the valley degeneracy in the TMDC would represent significant progress in the field of Valleytronics. This thesis sets forth a path forward toward achieving this goal using the semiconducting AFM CrPS4 and the TMDC WSe2, including the necessary fabrication procedure.
ATTACHMENT STATES OF MIND AND EARLY INTERVENTION AS PREDICTORS OF MIDDLE CHILDHOOD PARENTING OUTCOMES
(University of Delaware, 2023-05) Costello, Jacqueline
The current study aimed to explore how a parent may reflect on their attachment experiences (their attachment state of mind) and participation in an early parenting intervention, which affects parenting behaviors with their eight-year-old children. The Adult Attachment Interview was used to classify attachment state of mind for 74 parents. Parents were then randomized to receive an attachment-based or a developmental education intervention when their children were infants. During a middle childhood follow-up visit, parents completed the Attachment Script Assessment to measure their secure base script knowledge, and parent-child dyads completed a conflict discussion task to measure parental sensitivity. Consistent with Zajac et al. (2019) but with a different task, parents with autonomous states of mind displayed more sensitive caregiving when their children were eight years old than those with non-autonomous states of mind. These findings add to the robust literature supporting more positive outcomes for parents and their children later in life when parents have consistent and coherent representations of their attachment-related memories and participate in an attachment-based intervention.
“We Could Only Plan So Much Because Things Were Changing So Quickly”: COVID-19 and its Impacts on High School Education
(University of Delaware, 2023-05) Vasquez, Britney Sue
The COVID-19 pandemic brought about many changes and exposed vulnerabilities among varying populations both in the United States and globally. The event has required the need for adaptation and recovery efforts, especially in education. The majority of schools around the nation shut down quickly in March 2020 in response to COVID, forcing many teachers and administrators to adapt to a “work-from-home” environment promptly. Disparities arose when the needs of students did not match what they had grown accustomed to in past years with face-to-face instruction. Research from the summer of 2021 identified vulnerable populations and groups within a Delaware school district and weaknesses with the transition from online to in-person. Continuing with this investigation, I conducted interviews with teachers and administrators from a public high school in Delaware to gain an understanding of the challenges, adaptations, and modifications that were in place as instruction returned to in-person during the 2021-2022 school year. From these interviews, I was able to assess the challenges students experienced as a result of the pandemic, and how these needs were addressed. Teachers were compelled to consider students’ needs individually and adapt their lessons to better fit those emerging needs. While many of these strategies were able to help teachers instruct their students throughout the school year, vulnerabilities arose and some students were left behind. Many teachers were faced with burnout and stress as they returned to in-person instruction and new challenges in expectations and engagement arose. The results of this study provide insight into the extent to which the COVID-19 pandemic affected students’ and teachers’ abilities within schools. As the pandemic exacerbated the challenges many students in the school had already routinely experienced, such as economic disadvantages, lack of technological access, language barriers, and intersectionality, it forced educators to consider these vulnerabilities in ways they may not have had before in the classroom. Teachers were made to acknowledge and attempt to work past these issues to accommodate their students and reach them via remote and hybrid learning.
Collection and Validation of Patient Self-Reported Race, Ethnicity, and Language (REL) Information In a Postpartum Setting
(University of Delaware, 2023-05) Mehta, Shivani
As healthcare organizations move toward accountable care agreements, and move away from fee-for-service, there is a greater need for healthcare organizations to have stronger data to support population-based interventions. Moreover, literature has highlighted the discrepancies in collecting identity-based information from patients, including information regarding patient race, ethnicity, and language (REL). REL data has multiple policy and clinical implications as it is utilized to not only determine the allocation of funds for programs but also is used to create evidence-based interventions to decrease health disparities. If the core of this data is incorrect, then resource allocation is futile. More importantly, there is a potential that the resources and interventions that are being created using this data are now not effectively reaching and impacting these communities. Prior research demonstrates that there are large disparities in women’s health, especially by race.1 Given what we know about the nature of flawed data, these disparities are potentially increased or inadequately captured by current interventions. In an effort to assess organizational capacity to collect REL data and identify where discrepancies in the documentation of REL data may occur, this quality and safety improvement project assesses the practices of collecting REL data from patients, as well as concurrence or discrepancy in how REL data is documented within the patient’s chart and how they choose to self-identify. These concurrences and discrepancies were measured with a two-pronged approach where one prong involved patient survey of self-identified REL information and the second involved collection and validation from the Electronic Health Record (EHR). Study results demonstrated an overall concordance between the two data corpuses; however, the discrepancies and variation in certain minority groups were noteworthy. Given the results, the main finding is the need for an EHR with broader fields and/or allowing patients to self-identify their demographic data to allow for the validation of patient identities, create accurate data corpuses, and improve patient health outcomes. Once modified, we expect researchers to have more accurate and credible data to identify health disparities from, driving the eventual closure of the inequities seen within multiple minority populations.
DESIGN OF THE MR-STRETCHFINGERS DEVICE FOR THE STUDY OF NEUROMECHANICS OF STRETCH REFLEXES IN THE FINGER MUSCLES
(University of Delaware, 2023-05) Sivasankar, Manju
Human motor control consists of feedforward and feedback mechanisms, both aiming to reach a desired muscle state. Feedforward control does not involve sensory feedback and instead generates a movement based on the desired state. In humans, feedforward control is involved in voluntary reactions to a stimulus [1]. By contrast, feedback control considers movement errors and sensory feedback, with the aim of correcting movements. However, feedback control occurs on several timescales, and the speed of these responses is constrained by the neuromuscular pathways required for producing them. One method of feedback control in humans is stretch reflexes. Long latency responses (LLRs) specifically are believed to occur due to a combination of inputs from the corticospinal tract (CST) and reticulospinal tract (RST). LLRs are important to study biomedically, as they are involved in many neurological diseases that affect voluntary motor control. The CST can be damaged due to stroke [3]. For instance, 50% of people who experienced a stroke have a residual motor disability which can be due to reduced corticospinal drive resulting in a loss of movement accuracy and muscle flaccidity [4]. The RST can assume some of the lost CST function; however, the RST’s role in regaining motor function is not well understood. Understanding the role these pathways play in finger control at the metacarpophalangeal (MCP) joint has not been extensively studied in the past. The goal of this project was to develop a device which would elicit long latency responses in participants, validate that these responses are elicited, and utilize fMRI imaging to map the neural pathways activated during perturbations. In Aim 1 we present the development of the MR-StretchFingers device, which aims to apply perturbations at the MCP joint. We then present results which show that the device specificationsare met and it is capable of applying perturbations at the MCP joint and limiting other movement within those specifications. In Aim 2, we examine the signal-to-noise ratio (SNR) measured using surface electromyography (sEMG) in two muscles: first dorsal interosseus muscle which aids with flexion of the index finger, and the flexor digitorum superficialis muscle, which aids with middle/ring/pinky finger flexion. Results show that SNR was maximal during flexion movements corresponding to either index or middle/ring/pinky flexion, matching the physiological understanding of the muscles. Further, the results were of similar magnitude to SNR values for other muscles in literature. We then present an LLR study, which aimed to determine if LLRs are being elicited. We found that LLRs were being elicited in all cases at the group level, in both FDI and FDS with background torque applied by either the index finger only or middle/ring/pinky fingers only. Finally, we present an MRI conditions pilot which aims to find a control and experimental condition suitable for fMRI imaging. The results indicate two conditions which were suitable. In Aim 3, we present an MRI pilot study, which involved simultaneous mechanical perturbations by the MR SF with fMRI. The results indicate that there is some activation in the motor cortex and brainstem due to LLR modulation. Overall, this study provides preliminary evidence that there is subcortical and cortical activity that modulates the LLRs elicited by finger muscles. Future studies can expand on these results by including more participants and fine tuning the pro tocol to provide a clearer understanding of the neural correlates of LLRs and how the LLR in finger muscles are modulated by factors such as the perturbation veloc ity. Further, other factors affecting LLRs, such as task instruction or varying levels of background torque can be examined both outside and inside the MRI to understand LLR modulation. These findings can increase our understanding of human secondary motor pathways and lead to new rehabilitation strategies and therapies that can aid individuals with various motor impairments.
Investigation of Cell Type-Specific Loss in the Nucleus Reuniens of the Midline Thalamus following Single-Day Alcohol Exposure in a Rodent Model of FASD
(University of Delaware, 2023-05) Gustafson, Sarah
Fetal Alcohol Spectrum Disorders (FASDs) is an umbrella term used to describe multiple developmental disorders stemming from the prenatal alcohol exposure that are manifested by deficits in growth development, cognitive impairments, and physical abnormalities. 2-5% of live births in the US are affected by FASD and result in lower brain volume, brain anomalies, and behavioral deficits including impaired executive function. Executive function (EF) defines a set of cognitive controls that aid in the formation of goal-directed movements and regulating self-control; EF has been shown to relate to medial prefrontal cortex (mPFC) and hippocampus (HPC) activity. An intermediary structure, the nucleus reuniens (Re) of the midline thalamus, facilitates communication between the mPFC and HPC and is known to be damaged by prenatal alcohol exposure. A damaged Re is known to produce deficits in EF due to inefficient communication in the mPFC-Re-HPC circuit. This study employed a rodent model of third-trimester single-day binge alcohol exposure (AE) to evaluate neuroanatomical effects of neonatal alcohol exposure. Specifically, we examined moderate (3g/kg/day), and high (5/25g/kg/day) doses of ethanol compared to a sham-intubated control group. In conjunction with histological immunofluorescence staining, this study measured the numbers of specific cell populations in Re to assess levels of cell loss at 12hrs after AE. Specifically, we estimated the total number of neurons and oligodendrocytes in Re by labelling these cells with specific antibody markers NeuN (neuronal marker) and CC1 (marker for mature oligodendrocytes). No significant effect of postnatal treatment was found on neuron and oligodendrocyte populations in Re which indicates that cell loss might occur later than 12 hours following AE, as found in studies examining apoptotic-cell expression at 5 and 24 hours (Phanithi, et al., 2000). Additionally, no significant effect of alcohol exposure on reuniens volume was found, indicating that reuniens volume was not compromised within 12 hours of AE. This study aids in our understanding of FASD and adds to the general portrait of the effects of ethanol on the brain and Re
SYMBIONT THERMAL HISTORY AND SENSITIVITY INFORM PHOTOCHEMICAL PERFORMANCE IN THE SEA ANEMONE EXAIPTASIA DIAPHANA DURING ACUTE HEATING
(University of Delaware, 2023-05) Lane, Willa
Increasing seawater temperature due to global climate change is one of the largest threats to coral reefs. Excess heating often results in the host expelling the symbiotic algae, leading to a phenomenon commonly called coral bleaching. However, in some symbioses, these algae have the capacity to adjust to heating and can modulate this stress response. I examined how two genotypes of the symbiotic dinoflagellate Breviolum minutum responded to acute heat stress in the sea anemone Exaiptasia diaphana. Two phenotypes were tested for each genotype, one of which was thermally tolerant and previously exposed to gradual heating in free-living culture, and the other of which was thermally sensitive (i.e., wild-type) and naïve to heating. Anemones were acclimated to two different light levels to determine if photoacclimation differed by symbiont type, and if photoacclimation and symbiont type interacted to change the heat stress response. Anemones were then exposed to six hours of acute heating (from 24°C to 28, 32, 34, and 36°C), followed by a 16-hour recovery period at 28°C. At the end of acute heating, the maximum quantum yield of photosystem II (Fv/Fm) decreased with increasing temperature for all groups, but thermally selected algae exhibited less decline at low light levels. By the end of the recovery period, anemones exposed to 34°C showed some recovery in photochemistry, while Fv/Fm remained low in anemones exposed to 36°C. While Fv/Fm was sensitive to short-term heating, symbiont density and chlorophyll concentration remained similar to control values, and animal-based reactive oxygen species production did not increase with temperature. Overall, thermally selected symbionts did confer some tolerance to the host, and acute heat stress may predict the overall thermal tolerance of host-symbiont pairings. However, both the particular response variables and the time at which they are measured are critical for accurately determining short-term thermal responses in this symbiosis.
The Influences of Misinformation on Incidences of Politically Motivated Violence in Europe
(University of Delaware, 2023-05) Rulis, Mina
In the modern era of social media and related forms of electronic media, the issue of misinformation has become increasingly prevalent. To this end, as recent US presidential elections and experiences in Ukraine in the lead-up to the 2022 Russian invasion each suggest, transnational misinformation in particular poses an increasing threat to the security and stability of modern nation states. Furthermore, at least anecdotally, there are claims of a direct relationship between misinformation narratives and domestic acts of politically motivated violence. Yet such claims lack systematic empirical evidence, especially as it relates to the global spread of misinformation by state-based or transnational actors. As these effects of transnational misinformation on domestic political unrest remain understudied, I collect and evaluate empirical evidence of such an association. My research more specifically assesses the effects of transnational misinformation on several distinct forms of domestic political violence within the context of Europe, sharpening our empirical understanding of the purported association between misinformation and political violence. This is achieved through the fusion of a fine grained spatial temporal dataset of confirmed instances of news-based misinformation with daily level event data on incidents of political conflict. These combined data are then modeled and analyzed using univariate and bivariate descriptive statistics and multivariate LASSO regression models of misinformation in Europe for the period covering January 2015 to May 2022. These analyses imply a positive association between misinformation and political violence in Europe for this time period. These findings additionally indicate that this association is much stronger for civilian to government violence events than it is for civilian to civilian violence. Altogether this thesis accordingly provides novel empirical evidence for the pernicious effects of transnational misinformation on political violence.
IMPACT OF VITAMIN B12 ON C. ELEGANS MODELS OF ALZHEIMER’S DISEASE
(University of Delaware, 2023-05) Salsini-Tobias, John
Alzheimer’s disease (AD) is a neurodegenerative disorder characterized by atrophy of neurons in the brain and there are currently an estimated 6.5 million individuals afflicted in the United States. Evidence suggests that build-up of toxic amyloid-beta (Aβ) in the brain is a pathogenic feature of AD. The genetic model organism C. elegans provides a useful system to examine how the modifiable risk factor diet affects Aβ-induced proteotoxicity. Expression of Aβ in C. elegans body-wall muscles causes time-dependent paralysis, allowing for easy determination of factors that impact proteotoxicity. Previously, the Tanis lab has shown that supplementing with the nutrients vitamin B12 and choline protects against Aβ induced paralysis and bioenergetic defects by impacting the methionine/SAM cycle. Phosphatidylcholine (PtdCho) has been observed at reduced levels in individuals with AD and can be synthesized by SAM dependent methylation of phosphoethanolamine or directly from choline through the Kennedy Pathway. To further explore the protective potential of vitamin B12 and choline, I employed a C. elegans strain that expresses Aβ pan-neuronally and exhibits chemotaxis defects in response to the attractant isoamyl alcohol (IA). Attraction to IA was quantified with a chemotaxis index (CI). In this assay, all groups were attracted to the IA treatment, with a significantly lesser attraction observed for Aβ-expressing animals without B12 supplementation. This suggests that Aβ was detrimental to chemotaxis ability and that vitamin B12 supplementation, but not choline supplementation, is protective against Aβ-induced proteotoxicity in this neuronal model. I then developed a protocol for conditioning the animals to IA in the absence of food before performing the assay to determine if the animals could learn that IA is associated with starvation, however, the results were inconsistent. Another area of my thesis work focused on the impact of fatty acid synthesis on Aβ proteotoxicity. Vitamin B12 availability in the diet decreases transcription of the desaturases FAT-5 and FAT-7. To determine if loss of fat-7 affected the protective impact of vitamin B12, I created a strain with a mutation in fat-7 and the body-wall muscle Aβ transgene by genetic recombination. In addition, I used CRISPR-Cas9 to knockout fat-5 in the Aβ animals. We then performed paralysis assays and found that loss of either fat-5 or fat-7 did not impact the vitamin B12 dependent delay in paralysis, indicating that these genes are not required for the protective effect of B12. In conclusion, vitamin B12 has a protective effect in multiple C. elegans models of Aβ-induced proteotoxicity and this is independent of its impact on fatty acid synthesis.
INTERSECTIONS OF HOUSING AND TRANSPORTATION INSECURITY IN DELAWARE
(University of Delaware, 2025-05) Schultz, Lawson
To improve conditions for low-income residents, research with an integrated focus on the combined impacts of housing and transportation on people's experiences is critical. Delaware's population has been increasing faster than the national average, adding pressure on the housing market. This has caused securing affordable and safe housing to be increasingly more difficult for low-income residents. This research aims to connect information on housing and transportation insecurity in Delaware to investigate the accumulation of the two disadvantages. The findings are based on interviews with residents who use housing vouchers, state representatives, and staff members of state agencies. The experiences of residents who use housing vouchers reveal gaps in the current resources and systems in place that contribute to housing and transportation instability for low-income families. Residential instability or the risk of it and limited housing choices were consistently experienced by all the residents interviewed both before and after receiving housing vouchers. Additionally, some participants emphasized the significance of having a personal vehicle contributing to their overall well-being, despite the related financial burdens. The conversations with DSHA, HAD, DART staff members, and state representatives consistently reflected the concerns found within previous literature regarding the lack of affordable housing, landlords choosing not to accept housing vouchers, concentrated poverty in Wilmington, and the redevelopment of manufactured housing communities. Additionally, these conversations also revealed novel information about increasing action within these organizations. The findings, overall, emphasize the need for policy changes that address the underlying issues of residential instability and limited housing choices for low-income households. It is essential that future research continues to include the perspectives of low income residents in the development of policies and programs relating to housing and transportation across the state.
THE EFFECT OF CARDIAC-SPECIFIC HSP90 KNOCKOUT ON THE GENE AND PROTEIN EXPRESSIONS OF CALCIUM-HANDLING PROTEINS
(University of Delaware, 2023-05) Romano, Migachelle
For the heart to function and pump blood to the body, it must contract following a series of events called excitation-contraction (E-C) coupling to link the electrical excitation of the cardiomyocytes to actin-myosin cross-bridge formation. Regulation of cytosolic calcium levels is crucial to E-C coupling. Particularly, sarcoplasmic reticulum calcium reuptake, governed by the calcium ATPase (SERCA2A), has known to be the main dictator for the strength of contraction and relaxation. Indeed, β-Adrenergic (βA) stimulation during fight-or-flight response increases contractility by phosphorylation of phospholamban (P-PLN), a SERCA2A inhibitor during basal conditions. Increasing P PLN will enhance SERCA2A activity, thus cardiac contractility. Previously, our lab has shown that Heat Shock protein 90 (HSP90) can form a complex with PLN/SERCA2A via interaction with a hematopoietic associated protein X-1 (HAX-1). However, the functional consequences of this interaction remain to be elucidated. Thus, my goal is to study the role of Heat shock protein 90 (HSP90) on each individual calcium handling proteins such as PLN, SERCA2A and HAX-1 and its effect on heart contraction. In addition, HSP90 is involved in regulating G-protein coupled receptor kinase-2 (GRK2), a protein that can deactivate the β-adrenergic receptor by phosphorylation. So, understanding the expression of GRK2 in KO mice could give me more insight into the role of HSP90 in the βARs regulation on calcium kinetics as well. Because of the importance of calcium recycling in heart contraction, I hypothesize that HSP90 KO may increase calcium recycling by causing the downregulation of PLN, a SERCA2A inhibitor, without affecting the protein expression of SERCA2A, HAX-1 and GRK2. To test the hypothesis, I used cardiac-specific HSP90 knock-out (KO) mice to study the expression of the calcium recycling proteins of interest: GRK2, SERCA2A, PLN, and HAX-1. After extracting the heart of HSP90 KO, I performed a western blot and quantified the data. In addition, I performed a reverse transcription-quantitative polymerase chain reaction (RT-PCR) to analyze the effect of the KO mice on the mRNA expression of the same calcium handling proteins. The data showed no significant change in protein and gene expressions for both GRK2 and SERCA2A. The hax-1 mRNA expression decreased significantly but its protein expression remained the same across the groups. In addition, PLN protein expression decreased significantly in the KO group, but the P-PLN did not change. After comparing the ratio of P-PLN to PLN to gain an insight on the activity of the βA signaling pathway, the data revealed no change in phosphorylation before or after HSP90 KO. In this regard, I proved that when HSP90 is KO, only PLN protein is downregulated. The downregulation of PLN may result in increased contraction by relieving SERCA2A function. Therefore, HSP90 appears to have a direct effect on calcium cycling in the heart, which could subsequently impact contractility
Climate Change Misinformation And Corporate Interference In the 20th Century to Present
(University of Delaware, 2023-05) McGuire, James
Climate change has become a major concern among many Americans who fear for the well-being of the planet if the issue is not properly addressed. Despite this, little has been done to limit the carbon emissions that cause climate change, and the discussion around climate change has become partisan. To understand why this has occurred, this paper studies the actions of leading multinational carbon emitting companies Exxon, Shell, Koch Industries, and others from the middle of the 20th century to the present through the leading climate related research. This study reveals that these companies have pursued a comprehensive agenda for climate change misinformation. This campaign began with research of the issue prior to other climate scientists and awareness of the threat of climate change. Next these companies funded think tanks, news sources, and politicians to stifle the rising concerns of climate scientists and confuse the public. This study highlights how the narrative of climate change misinformation is very malleable and resistant to factual correction. This paper ends with a discussion of how to address climate change through greater education, the potential for lawsuits against these companies, and anticipation of future problems in seeking climate change regulations.
COMPARISON OF TELEHEALTH AND FACE-TO-FACE DELIVERY FORMATS IN SEATED PLAY INTERVENTIONS FOR CHILDREN WITH AUSTISM SPECTRUM DISORDER (ASD)
(University of Delaware, 2023-05) Dolan, Jillian
The study examines the comparison of Face-to-Face and Telehealth delivery formats as a means to deliver Seated Play (SP) interventions for children with Autism Spectrum Disorder (ASD). 15 children with ASD between the ages of 5 and 14 years old were included in this study and were given SP interventions using either the Face to-Face or Telehealth format. Child related outcomes such as fine motor, social, and affective states were analyzed in each format and parent and trainer surveys were also analyzed to understand the efficacy and feasibility of TH delivery formats in comparison to the standard of care F2F format. Child related average outcomes and change scores proved that there were no significant differences across the TH or F2F groups; however, F2F showed a statistical trend of greater improvements in fine motor outcomes compared to the TH subgroup. The surveys completed by parents and trainers revealed that both formats were feasible and effective, but the TH format requires greater parental involvement and involves more communication/technological issues than the F2F format. The results suggest that F2F and TH are both acceptable formats; however, TH should be used in areas where there is less access to F2F interventions or for those who prefer treatment from their own home and have the means to do so (e.g., better attention and ability to follow instructions and technology access).
THE EFFECTS OF SEXUAL MINORITY STIGMA IN CATHOLIC SOCIAL CONTEXTS ON YOUNG GAY MEN
(University of Delaware, 2023-05) Sweeney, Dan
Past work suggests that sexual minorities experience stigma in religious environments, which in turn leads to adverse mental health outcomes. However, the experiences of young sexual minority men in Catholic environments remains understudied. To explore these experiences, ten participants who identified as gay men between the ages of 18 and 25 in the United States were interviewed about their experience with the Catholic Church, experience coming out, and any suggestions they have for the Church or other young gay men with a similar Catholic background. Interviews were coded following standard qualitative methods. When it came to the family unit, some family members, especially grandparents, were more stigmatizing and hateful than others. Participants’ experience in primary and secondary school was highly stigmatizing. Instructors sent a variety of stigmatizing messages and peers bullied many of the participants. Participants encountered stigma in college but to a lesser extent, citing friends as a source of belonging. Every participant leaned away from Catholicism as a result of their experience with the Church, and the majority of participants currently identify as atheist or agnostic. Advice to the Church centered around equity and inclusivity and advice towards young gay men centered around seeking safe spaces free of homophobia and hate. Future studies should be directed towards behavioral health interventions that target young gay men with a Catholic background and ultimately, wide-scale changes are needed to remove stigma from the Catholic Church entirely.
Effects of Cell Migration on Polyethylenimine/pDNA Polyplex Transfection Efficacy and Mechanism
(University of Delaware, 2023-05) Hewes, Jacob
Nonhealing wounds have been the subject of decades of basic and clinical research. Despite new knowledge about the biology of impaired wound healing, little progress has been made in treating chronic wounds, leaving patients with few therapeutic options. The lack of treatments has created a major global burden on the healthcare system and resulted in high health care costs. In the past few decades, the field of nonviral gene delivery has garnered significant interest as one of the most promising strategies for the treatment of chronic wounds. Nonviral vectors have the advantage to deliver genes to target cells without the immunogenic or toxic responses associated with viral vectors, however, limited gene transfer efficacy remains a challenge. This work aims to address these challenge by optimizing the formulation of poly(ethylenimine) (PEI) nanocarriers for effective plasmid DNA (pDNA) delivery. PEI-pDNA polyplexes were synthesized with different N/P ratios to optimize polyplex properties, including size and zeta potential, and used to transfect NIH/3T3 cells in vitro. It was found that an N/P ratio of 10 produced the smallest and most positively charged polyplexes, resulting in the highest transgene expression. Furthermore, a simple in vitro wound model was developed and employed to study PEI-pDNA polyplex transfection during wound healing. Cells migrating to close the wound were found to be transfected more readily than cells that did not migrate. Additionally, the transfection efficiency in migrating cells was shown to decrease when less growth factors were present in the extracellular environment. Thus, this work demonstrates that PEI can be used to delivery therapeutic DNA and targeted delivery of transgenes to migrating cells during wound healing could serve as a viable strategy to enhance tissue repair and regeneration.
REDEFINING DYSTOPIA: Representative British Dystopian Novels 1872-2007
(University of Delaware, 2023-05) Hughes, Jillian
Dystopian fiction is a genre that has amassed both commercial success and the attention of literary scholars alike. Despite dystopian fiction’s popularity in mainstream culture and media, defining what it means for a novel to be dystopian is a challenge that literary critics still grapple with. The definitions that do exist, like Sargent’s definition of a dystopia, which is one of the most cited definitions, that states “a non-existent society described in considerable detail and normally located in time and space that the author intended a contemporaneous reader to view as considerably worse than the society in which the reader lived.” (Sargent 9) does not fully capture what it means for a novel to be dystopian. This project analyzes eight British novels considered to be dystopian over the time span 1872 to 2007. After reading the novels Erewhon (1872), The Fixed Period (1882), The Time Machine (1895), Brave New World (1932), 1984 (1949), A Clockwork Orange (1962), The Children of Men (1992), and Daughters of the North (2007), I sorted the novels into the following periods: the Victorian proto-dystopias, World War One to the fall of the Berlin Wall, and the contemporary period. I argue that the dystopian novel is one that criticizes some aspects of society contemporary to when the novel was written, and that it features an individual, alienated from and whose individuality is restricted by the society or government in which they live, but cannot escape.
DEVELOPMENT OF AN ENGINEERED TREATMENT SYSTEM FOR THE REMEDIATION OF BRINE-CONTAMINATED SOILS
(University of Delaware, 2023-05) Cobb, Holly
Produced water is a highly concentrated brine produced during the extraction of oil and natural gas from geological formations. When spilled, it threatens nearby vegetation and groundwater. The current way of dealing with produced water spills is to excavate the impacted soil and send it to a specialized landfill. This study is concerned with the lab-scale development of an engineered system to remediate salt contamination from produced water spills. Evaporative flux is the process where water passes upward through soil as it evaporates at the surface, carrying solutes with it. Crystallization modifiers are compounds that alter the precipitation of minerals, delaying the onset of crystallization and/or modifying crystal habit, until salts approach or emerge at the surface. Evaporative flux and crystallization modifiers provide the basis for the design evaluated herein, where a constant supply of treatment solution consisting of water and crystallization modifier is supplied at the base of contaminated soil and transports through soil via evaporative flux. A remediation system was devised in the lab based upon these ideas, where a Mariotte bottle which exerts a constant hydraulic head on the system is connected to a beaker containing a 3cm depth of contaminated soil. To create a brine-contaminated soil, a 3.8M salt solution saturates a loamy sand followed by oven drying. This contaminated soil was passively flushed with treatment solution containing various concentrations of a crystallization modifier for five days, before being dried and analyzed by depth. The electrical conductivity of each depth layer of the soil column was collected to understand where the salt was removed and where it remained. Lab-scale experiments show up to 96% removal using a 3mM potassium ferrocyanide solution. Experiments testing the ideal dosage and application of crystallization modifier, the potential use of fabrics to harvest salts, and the impact of using real produced waters were evaluated to improve this system before it is repeated at pilot scale.
MATRIX EXPRESSION IN PASSAGED CHONDROCYTES IS REGULATED BY TROPOMYOSIN 3.1
(University of Delaware, 2023-05) Rzepski, Alissa
Cartilage is an avascular tissue that allows frictionless mobility of joints. Cartilage cells (chondrocytes) reside in a matrix of collagens (type II collagen [Col2]) and proteoglycans (aggrecan [Acan]) to bear mechanical load [2, 10, 14]. Unfortunately, cartilage is incapable of self-repair and damage leads to cartilage degradation in osteoarthritis (OA). Autologous chondrocyte implantation (ACI) is used to treat small, focal cartilage defects. Chondrocytes are isolated from healthy regions of cartilage in damaged joints, expanded on stiff polystyrene to increase number, then reimplanted into damaged regions to stimulate repair. Unfortunately, ACI ultimately fails [9, 18, 20, 23]. During expansion, chondrocytes become larger, elongated, and express fibroblastic matrix (type I collagen [Col1]) and contractile (transgelin [Tagln]) molecules, which are biomechanically inferior [2, 14, 22, 23, 39, 41, 43]. Additionally, cellular filamentous (F-)actin organization changes from cortical F actin to F-actin stress fibers. Our previous research indicates formation of F-actin stress fibers plays a key role in chondrocyte dedifferentiation [1]. In the present study, we examined ways to repress F-actin stress fiber formation by examining master regulators of actin networks, the Tropomyosins (Tpm), which bind and stabilize specific F-actinnetworks [32, 41]. Therefore, we hypothesize that targeting specific stress fiber actin stabilizing Tpms will repress F-actin stress fiber networks and promote chondrogenic redifferentiation after expansion.

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