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Transposon mutagenesis used to observe factors essential to growth using 5-deoxy-D-ribose
Get PDFS-adenosyl-L-methionine (SAM) is a compound used by all organisms for various cellular processes. When SAM undergoes radical SAM reactions, a deoxynucleoside known as 5’-deoxyadenosine (5dAdo) is produced. SAM may also be converted into another nucleoside known as 5’ methylthioadenosine (MTA), which is sulfur-containing. In Extraintestinal Pathogenic E. coli (ExPEC), MTA and 5dAdo are further used by the cell as a carbon source through a metabolic pathway called the dihydroxyacetone phosphate (DHAP) shunt. By studying which genes are required for the use of 5dAdo and MTA for growth by ExPEC strains we can gain a new perspective on how bacteria can grow and proliferate in a variety of different environments. Initially, it was observed that the byproducts of SAM metabolism, MTA and 5dAdo, were metabolized to the precursor metabolite DHAP by the DHAP shunt. What was unknown was if any other factors affected the cell’s ability to use the DHAP shunt for growth. Building a library of isolates using random transposon mutagenesis allowed us to scan the E. coli genome and identify these factors. The pRL27 plasmid vector containing the Tn5 transposable element made this study possible. Using certain selectivity elements of the transposon such as Kanamycin resistance and pir-dependent replication site allowed us to keep track of the Tn5 element. We were able to isolate a total of 36 isolates that showed significant differences in growth patterns on glucose versus 5-deoxyribose, a metabolite of 5dAdo metabolism in E. coli. Of these isolates, the majority of them had Tn5 insertions in genes relating to transporters and lipopolysaccharide synthesis. This transposon mutagenesis library will show us what other genes are required for use of the DHAP shunt for growth. In the future, these results may help researchers and medical professionals understand how ExPEC can utilize the DHAP shunt as a carbon salvage pathway to survive in various areas of the nutrient-scarce environments in the body.No embargoAcademic Major: Microbiolog
The EBLM project XV. 4 Eclipsing M-dwarfs Characterized With TESS and HARPS
No full textM-dwarfs are the least constrained type of stars in our galaxy despite them being the most abundant. The literature on M-dwarfs is fairly limited in terms of constraints and properties of these stars. To better study them, we are using eclipsing binaries to constrain their properties in a similar manner we do for exoplanets. We have selected four binary targets to fully analyze using TESS light curves, HARPS radial velocity (RV) measurements, and EXOFASTv2 to synthesize more precise data to best constrain M-dwarfs. This paper provides precise fundamental properties of four M-dwarf stars, including the mass ratio, radii, and temperatures of the orbiting stars. The primary goal of this paper is to expand the literature on constrained principles of M-dwarfs to better study them and their companions.Ohio State University Department of AstronomyNo embargoAcademic Major: Astronomy and Astrophysic
Lamina Cribrosa Morphometry Changes during Intraocular Pressure Elevation: Analysis of High Frequency Ultrasound Images from Human Donor Eyes
Get PDFGlaucoma is a leading cause of irreversible blindness, affecting over 80 million individuals globally. Intraocular pressure (IOP) is a primary risk factor, but how IOP affects the morphometry of the posterior eye where glaucoma damages occur is not well understood. This research focuses on two primary aims: (1) investigating the relationship between IOP and lamina cribrosa (LC) morphology, and (2) improving ocular ultrasound image quality using deep learning-based denoising algorithms to better extract morphological features. Various deep learning architectures, including convolutional neural networks, autoencoders, and diffusion models were evaluated for denoising ultrasound images. Performance was assessed using metrics such as peak signal-to-noise ratio (PSNR) and contrast-to-noise ratio (CNR). Ultrasound images of the posterior eye were previously acquired from human donor eyes controlling IOP from 5 to 30 mmHg. LC thickness and anterior lamina cribrosa surface depth (ALCSD) changes were analyzed in manually segmented ultrasound images. Results indicate that LC thickness decreased with increasing IOP, while ALCSD did not significantly change. Denoising efforts were made using deep learning architectures like autoencoders and diffusion models, but did not result in any improvement. A fine-tuned vision transformer was able to accurately generate LC masks, enabling automated segmentation of ocular ultrasound. This work contributes to the understanding of pressure-related morphological changes in the posterior eye and lays a foundation for more robust detection of posterior eye changes associated with IOP elevation.Undergraduate Research Scholarship ($2500)No embargoAcademic Major: Biomedical Engineerin
Central to Success: Measuring the Effect of Discoursive Centrality on Legislative Effectiveness in Congress
No full textMembers of Congress leverage their speeches to shape policy debates, express their ideological positions, and send cues to fellow legislators—but how effective is their rhetoric in advancing legislation? This thesis explores the relationship between congressional speeches and legislative effectiveness, using data from the 96th to the 114th Congresses (1979-2016). Speech and sentiment similarity among legislators are analyzed using two RoBERTa models, and four networks are constructed: two fully connected and two binary networks based on speech content and sentiment. Centrality measures (node strength, eigenvector centrality, and PageRank) are averaged to assess members’ influence, which is then analyzed using linear fixed effects regression. Results show influential House members in both speech and sentiment networks are more legislatively effective. In the Senate, effectiveness is linked to influence in binary networks but not fully connected ones, likely due to institutional differences. This network-based approach highlights how individual linguistic patterns drive broader shifts in legislative outcomes.ASC Honors Committee - Undergraduate Research ScholarshipCenter for Effective Lawmaking - Small Grant WinnerA one-year embargo was granted for this item.Academic Major: Political Scienc
Tracking Urbanization's Impact on Bird Functional Diversity Over Time
Get PDFIntroduction:
Urbanization drives major changes in the natural environment and its role in bird diversity decline has been the focus of extensive research. Most studies assess the effects of anthropogenic stressors on biodiversity using a space-for-time substitution, examining urbanization levels across a gradient from rural to highly urbanized environments. In contrast, this study investigates how different levels of urbanization change affect bird diversity through time. My goal is to determine whether a temporal approach yields results similar to or different from those found in space-for-time substitution studies.
Methods:
The study region includes Indiana, Ohio, and Kentucky, encompassing the metropolitan areas of Indianapolis, Columbus, Cincinnati, and Louisville. Using eBird data, I first developed Species Distribution Models (SDM) to generate predictions of bird presences and absences for 134 species in two time periods: 2013 and 2023. Using these predictions, I then assessed bird diversity using four metrics: species richness, functional richness, functional evenness, and functional divergence. The latter three metrics were derived by analyzing the trait space, an n-dimensional representation of species' traits that influence how species interact with and shape their environment. All avian diversity metrics were obtained for each year for each 3kmx3km site across the study region. I used NLCD impervious surface data to quantify change in urbanization. Change in avian diversity was then modeled as a function of change in impervious surfaces.
Results:
Model results indicated that functional richness decreases with increasing levels of urbanization. Specifically, sites with medium and high levels of urbanization change saw the most dramatic declines in avian functional diversity. In contrast, I found that increasing urbanization led to increases in species richness. Specifically, sites characterized by medium change in urbanization have seen larger increases in species richness compared to sites characterized by no change, low change, or high change in urbanization. Finally, sites with high levels of urbanization had an increase in functional evenness and functional divergence compared to sites with no change in urbanization.
Conclusions:
Findings of declining functional richness and increasing species richness with increasing temporal change in urbanization corroborate findings from previous space-for-time substitution studies that focused on spatial urban gradients. These replicated patterns provide justification for using the space-for-time substitution as a proxy for temporal change in urban development and thus for assessing the effects of urbanization on avian diversity change. By reinforcing the findings of previous studies, my work broadens our understanding of urbanization’s impact on biodiversity and provides a blueprint for urban developers and conservation managers to ensure that adequate habitat for birds is preserved during urban development.No embargoAcademic Major: Data Analytic
Nation of Strangers: An Exhibition on the History of Immigration in the United States
Get PDFNation of Strangers is an interactive timeline exhibition for middle and high-school-age children. It is designed to educate and engage viewers as they learn about key factors such as the economic, cultural, and demographic impact of immigrants during each major immigration wave in the United States. The history of immigration is a topic that doesn’t get the attention that it should in American History classrooms across the U.S., even though immigrants were the foundation of what the country was built on. By creating an exhibition on the history of immigration in the United States it will allow viewers to gain a deeper understanding of the nation's past, present, and future. It also provides a factual basis for celebrating the diverse contributions of immigrants, recognizing their struggles, and appreciating their role in shaping American society.
Secondary research was the primary source of research during this project. It involved researching the key historical waves of immigration, along with the cultural and demographic impact on the development of the United States. Time was also spent researching what makes children's museums and experience designs, aimed at children, successful. This was accomplished by looking at case studies, scholarly research articles, and databases discussing the concepts, and user personas.
After conducting my research I then used my insights to create an interactive timeline-based exhibition on the five major immigration waves that could be accessed both physically and digitally. I created the physical exhibition for the hallway gallery space in Hopkins Hall using the content that I had found during my secondary research. I digitally designed the space using both Illustrator and Indesign to bring it to life. In addition, I created an application prototype for the exhibition using Figma, so viewers can explore the exhibition content from any location.
In conclusion, this exhibition on the history of Immigration will be beneficial for all viewers across the globe who want to learn about the topic. With the current negative climate surrounding immigration in the United States, the creation of a children-friendly exhibition can help them to have a more positive and educated view of the topic.No embargoAcademic Major: Visual Communication Desig
Utilizing an Electronic Discharge Medical Readiness Tool to Increase Nurse Documentation Completion
No full textDischarging patients from the hospital setting requires extensive planning to ensure they are prepared to maintain their wellness outside the hospital. Delays in discharging patients are costly to organizations and patients. This Doctor of Nursing Practice (DNP) quality improvement project aims to help identify patients ready for discharge by using an electronic medical readiness tool to prepare patients for discharge. At a Midwest pediatric hospital, the previous process of utilizing a paper readiness tool had a low completion rate. This project used Lewin’s Change Model and the Plan, Do, Study, Act model to implement a transition from the current process of using a paper medical readiness tool to an electronic form of the tool. In addition to the tool, incorporating a discussion of the medical readiness of each patient’s progress in the interdisciplinary rounding was needed to increase awareness of patient progress towards discharge. The tool, combined with daily awareness during interdisciplinary rounding, was expected to have patients discharged without delay within two hours of being identified as medically ready. During the 12-week implementation period, a total of 64 patients were discharged. Of those, 78% were discharged within two hours of being identified as medically ready. This was attributed to the communication and consistent review of the discharge progress during interdisciplinary rounds. Although the nursing rate of completion of the electronic tool was only 28%, delays in discharge were not linked to tool completion. These findings suggest that a readiness tool supports discharge planning in combination with active interdisciplinary communication.A three-year embargo was granted for this item
Influence of Fetal and Maternal Factors on Hair Cortisol Concentrations in Neonatal Foals
Get PDFIt is well known that cortisol plays an important role in the fetal maturation of many species, including the horse. Although plasma, salivary, and fecal samples reflect acute cortisol concentrations, they are not able to offer the long-term retrospective analysis that hair samples can provide. In the horse, hair starts to grow at approximately 270 d of gestation. Therefore, non-invasive measurements of cortisol concentrations in hair samples collected at birth may reflect cortisol accumulation during the last 50-90 d of gestation and may provide insight to factors influencing cortisol concentrations during fetal development. The purpose of this study was to evaluate hair cortisol concentrations (HCC) of neonatal foals in relation to their physical characteristics (sex, birthweight, coat color) and maternal factors (parity, gestation length, month of parturition). Hair samples were collected from healthy Quarter Horse foals (n=8) born at The Ohio State University Equine Facility within 2 hr of birth. Cortisol concentrations were measured via enzyme-linked immunosorbent assay (ELISA), and data were analyzed using PROC MIXED and PROC CORR (SAS v. 9.4). The mean HCC of neonatal foals in this study was 35.3 ± 5.6 pg/mg. There were no differences observed in the HCC between colts and fillies (33.3 ± 2.4 pg/mg vs. 38.6 ± 3.0 pg/mg, p = 0.22). HCC were also not influenced by the foal’s birthweight or base coat color (p > 0.05). Similarly, HCC were not influenced by the mare’s parity, gestation length, or month of parturition (p > 0.05). No significant correlations were observed between the HCC of the neonatal foals, their physical characteristics, or maternal factors evaluated in the present study. Hair samples provide a non-invasive approach to measuring cortisol concentrations in neonatal foals.No embargoAcademic Major: Animal Science
A Grain Size Analysis of Southern Cascadia Marine Sediment
No full textThe intention behind this research was to better understand the grain size of fourteen previously untested cores from the Southern Cascadia Subduction Zone. A better understanding of grain size from this area could be useful in an improved understanding of hazards associated with seismic activity. Another goal of this research was to lay groundwork for more research to be done in the future. Samples were collected from the United States Geological Survey Coastal and Marine Science Center core repository in Santa Cruz, California. One to two gram samples were collected every two centimeters from cores JPC 1, 4, 5, 6, 31, 32, 34, 35, 36, 37, 38, 39, 40, and 41 and then analyzed for grain size at The Ohio State University Marine Geology and Geohazards Laboratory. Grain size was determined with a Horiba Partica LA – 960V2 laser diffraction grain size analyzer. The data was plotted in standard ternary plots, percent-finer graphs, and downcore grain size graphs for each core. The overwhelming majority of cores were silt-dominated. There were also several instances of fining upward in the downcore grain size graphs for many cores. This suggests possible records of sediment gravity deposits in those areas.Cooperative Grant - (AWD115192) (PI Dr. Derek Sawyer)A one-year embargo was granted for this item.Academic Major: Earth Science
Expansion of rhesus macaque MAIT cells
Get PDFMucosal Associated Invariant T (MAIT) cells are a unique subset of T cells that bridge the innate and adaptive immune systems. Unlike conventional T cells, MAIT cells recognize specific microbial metabolites presented by an MHC-related protein 1 (MR1) (Toubal et al. 2019). Our research team previously developed a method to expand human MAIT (h MAIT) cells in vitro using immunomagnetic selection and stimulation with MR1-coated microspheres loaded with the potent agonist 5-OP-RU. Rhesus macaques (RM) are crucial animal models in translational research due to their immunobiological similarity to humans. While RM MAIT cells are similar to h MAIT cells (Rahman et al. 2020), limited studies have been conducted on their functionality due to challenges during in vitro expansion. This study aimed to adapt our previous method to expand RM MAIT cells in vitro for further investigation. Our findings demonstrate that RM MAIT cells can respond to microspheres coated with antigen-loaded species-specific MR1, similar to human MAIT cells. However, RM MAIT cells require additional costimulatory signals compared to their human counterparts for significant in vitro expansion. We were able to develop a method to expand RM MAIT cells in vitro. These results provide a foundation for further exploration of these important innate-like T cells in this critical animal model, potentially advancing our understanding of MAIT cell biology and its implications in translational research.No embargoAcademic Major: MicrobiologyAcademic Major: Biochemistr