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Ellie - Exteroceptive Light Locomotion In Eukaryote-Fungi, Brandon Etwarroo

Doctoral Dissertations and Master's Theses

Over the past decade, fungal research and its technological applications have expanded across multiple disciplines, including the emerging field of biohybrid systems. This thesis develops and evaluates a wireless, untethered mobile robot controlled by the action potential-like activity generated by Pleurotus ostreatus sporocarps under red, green, and blue optical stimulation. Light is applied to the sporocarps, the resulting electrical responses are recorded, and these signals are transmitted wirelessly to actuate the mobile robot. Both the action potential-like activity patterns and the robot’s movement trajectories were analyzed. The results demonstrate that wireless robotic control mediated by fungal electrophysiology is feasible. Overall, …

The Relationship Between Stress And Postpartum Depression-Related Behavior In Females And Its Potential Contribution To The Maternal Mortality Rate In The U.S., Sarah Chugh

Senior Theses

Stress, especially social stress, has been a leading cause of disruptive emotional behavior in humans, with pregnant and postpartum women being the most vulnerable to these effects. Our study aimed to investigate the effects of gestational social stress on postpartum behavioral outcomes. To accomplish this, we examined the following four key behaviors in female rats after being exposed to chronic witness stress (WS) during pregnancy: burying, freezing, rearing, and grooming. Burying behavior is used to assess a defensive response to threatening situations. Freezing responses are evaluated to show heightened fear or hypervigilance that follows stress. Rearing is measured as an …

Increased Backbone Rigidity Of Artificial Transcription Factors, Jasmine Glover, Emma Otey, Joanna K. Kwao, Nicholas Truex

Senior Theses

Programming DNA-binding proteins is an effective strategy for developing therapeutics that regulate gene expression. These proteins can directly bind to DNA to activate or repress transcription of specific genes. Zinc finger proteins are a class of DNA-binding proteins commonly found in eukaryotic organisms. Their DNA-binding function is derived from unique amino acid sequences within each domain that recognizes specific nucleotides, allowing each finger to selectively recognize three DNA base pairs. Adjoining of multiple domains in tandem allows recognition of a specific DNA sequence. Artificial transcription factors can be made of multiple zinc finger domains arranged in tandem and engineered to …

Evolution Of Antibiotic Responses During Chronic P. Aeruginosa Infections In The Human Lung, David Frank Ritz

Dartmouth College Ph.D Dissertations

Typical antibiotic susceptibility testing (AST) of microbial samples is performed in homogeneous cultures in batch environments, which does not account for the highly heterogeneous and dynamic nature of antibiotic responses. The most common mutation found in P. aeruginosa lineages evolved during chronic cystic fibrosis infections in the human lung, a loss of function of repressor MexZ, increases basal levels of multidrug efflux MexXY, but does not increase resistance by traditional minimal inhibitory concentration (MIC) assays. Here, we use single cell microfluidics to show that P. aeruginosa’s response to aminoglycosides is highly heterogeneous, with only a subpopulation of cells surviving exposure. …

Analyzing Antibody Immune Response In Α1,3galt-Ko Mice After Intranasal Vaccination Of Α-Gal Virus-Like Particle, Faith Brown

Honors Theses

In this study, we evaluated the immunogenicity of intranasal immunization with α-Gal-conjugated virus-like particles (VLPs) in an α1,3-galactosyltransferase-knockout (α1,3GalT-KO) mouse model that mimics the human immune response to the α-Gal epitope. The carbohydrate epitope galactose-α-1,3-galactose (α-Gal) is expressed on the cell surface of several pathogens, including Leishmania species. This molecule is absent in humans and has emerged as a promising immunogenic vaccine target. α1,3GalT-KO mice were intranasally immunized with 10 μg either Qβ-α-Gal or Qβ per nostril and boosted twice prior to sample collection. Blood and lung lavage samples were used to evaluate the antibody response. The Qβ-α-Gal group developed …

Effects Of “Zero Sugar” Energy Drinks On Microbial Proliferation In Relation To The Gastrointestinal Microbiome, Madison Hines

Honors Theses

Energy drinks have rapidly increased in popularity and availability in recent years. With the rise of high-caffeine beverages, complications due to caffeine consumption have become more common in younger populations. The aim of this study was to use controlled laboratory methods to determine the effect of energy drinks on a variety of organisms commonly found in the gastrointestinal (GI) tract. The diverse and dynamic nature of microbes in the gut makes conditions of the GI tract difficult to replicate in a laboratory setting. As an alternative, isolates of bacteria commonly found as normal flora in the GI tract were plated …

The Impact Of Pp1Β Cancer-Associated Polymorphisms On Pp1Β Protein Abundance And Cell Survival In Humanized Saccharomyces Cerevisiae, Kaylee Martinez

Honors Theses

PP1β is an understudied protein phosphatase that affects the cell’s ability to reproduce. It has been known to be an important part of the cell cycle. Mutations within PP1β have been found to affect that process and influence the development of cancer and disease. In this thesis, different PP1β cancer and disease associated polymorphisms are investigated through the use of humanized yeast. PP1β yeast variants are tested by using Live/Dead cell assay and western blot techniques. Live/Dead analysis was conducted on different strains grown at permissible temperature (room temperature) and non-permissible temperature (37°C) over the course of 6 or 48 …

Growing South Dakota (Spring 2026), College Of Agriculture, Food, And Environmental Sciences

Growing South Dakota (Publication of the College of Agriculture, Food and Environmental Sciences)

[Page] 2 National heritage, statewide research, local impact
[Page] 7 About the South Dakota Agricultural Experiment Stations
[Page] 14 Managing the mooo-ment: How SDSU researchers are looking to improve cow health during the Transition Period
[Page] 18 Discovering strength in science: How education through undergraduate research prepares students for the future
[Page] 20 From India to Brookings: One grad student’s path to make a world of difference in virology
[Page] 22 Solving a billion-dollar problem: Identifying disease-resistent wheat genes
[Page] 24 Unlocking manure’s potential: SDSU leads multistate study on the power of swine manure in growing better crops
[Page] 28 …

Developing A Range Prediction For The Imperiled Florida Harvester Ant (Pogonomyrmex Badius) Using Species Distribution Modeling, Noah Williamson

Honors Theses

The Florida Harvester Ant (Pogonomyrmex badius) was once widespread and commonplace throughout the sandhills of the Southeastern United States, providing key ecosystem services, such as seed dispersal and soil aeration. Over recent decades, however, Florida Harvester Ant populations have declined in some areas. Current literature postulates that Red Imported Fire Ants (RIFA), and the insecticides used to manage them, as well as further human encroachment onto their habitat, all likely contributed to Florida Harvester Ant population declines. Thus, to better protect these organisms, pursue data-driven conservation efforts, and guide management practices, more information about their nest site selection, as well …

Abundance Of Microplastics In The Water And Stream Fish Of Big Walnut Creek, David J. Hartman

Undergraduate Honors Thesis Projects

Microplastics are a major threat to both ecosystem and human health. In this study, I investigated the abundance of microplastics at five sites along Big Walnut Creek, Ohio including sites upstream, downstream, and within urban development. Samples were taken from the stream surface water and fish at each site. Microplastics were detected in the surface water and fish at all five sites with a total of 383 microplastic particles found in the 157 fish collected for this study. The mean concentration for all sites was 80.8 particles/m3 in the surface water and 2.4 particles per fish. Microplastics were almost entirely …

The Missing Lynx: Investigating Passive And Active Rewilding With The Eurasian Lynx, Isaiah Charles, Tatiana Flores, Isabella Lopez

Conservation Biology

The Eurasian Lynx (Lynx lynx) is a wild cat native to the boreal forests, mountains and grasslands of Europe and Asia (Bhattacharyya, 2025). The Eurasian lynx keep ungulate populations in check which allow for forests to recover from overgrazing, promoting biodiversity and ecological balance. However, the Eurasian lynx had become locally extinct across Europe by the 1900s due to habitat loss, hunting by farmers in retaliation for predation of livestock and the illegal fur trade. Conservation and ecological restoration efforts to rebuild the lynx population have been underway. Rewilding is a form of ecological restoration involving the reintroduction of a …

The Importance Of Body Size And Spatial Scale In Modeling Winter Bird Distributions, Carissa M. Mobley

Student Publications

Birds’ annual cycles include biologically linked breeding and non-breeding seasons, yet most research and bird atlases focus exclusively on the breeding season. There have been very few winter bird atlas projects in North America, and none have been published for the northeastern United States. Short daylight hours and harsh weather limit winter survey coverage, making species distribution models (SDMs) essential for addressing spatial gaps.

I evaluated the optimal spatial scale for SDMs across bird species differing in body size and tested whether optimal scale varies with body mass. Using 16,967 eBird checklists collected during the first winter survey period (December …

Pfas And Western Diet Effects On Adolescent Rat Feeding And Metabolism, Whesli Kim

Theses and Dissertations from DePaul University

Per- and polyfluoroalkyl substances (PFAS) are a class of widespread persistent organic pollutants associated with metabolic and neural dysfunction in humans. These processes are also affected by Western diet high sugar high fat contents. However, interacting effects of PFAS exposure and Western diet on metabolic regulation and feeding behavior have not been tested. Exposure to PFAS is high during sensitive gestational and neonatal periods of development. Adolescence is a key period where nutritional demands shift, eating habits are established, and gonadal hormones change. This study tests the hypothesis that early life exposure to PFOS alters adolescent metabolic function and feeding …

Analysis Of Mitochondrial Dna Haplotype Groups For South Texas Canids, Canis Rufus, After Past Hybridization Events, Isabella Lopez

Presentations - 2026

mtDNA: mitochondrial DNA; passed from maternal parent to offspring (Haplotype)

Haplotype:  a group of genes or genetic markers inherited together from a single parent (Haplotype)

Mitochondrial DNA haplotypes specific sequences of mtDNA that is passed exclusively from maternal parent to offspring (Giles et al. 1980)

Pro's:

It is passed unchanged from mother to offspring, meaning it is fairly stable (Giles et al. 1980)

Each cell has multiple mitochondria vs one nucleus , which means mtDNA it is more likely to be recoverable from degraded samples like scat (Templeton et al. 2013)

Microplastic-Mediated Delivery Of Di-Butyl Phthalate Alters C. Elegans Lifespan And Reproductive Fidelity, Chiara Angelyn Maldonado

Presentations - 2026

•The challenge: microplastic contamination •The question: How do microplastics and chemical contaminants affect living organisms? •The follow-up: What’s next!

Raptor Abundance And Occupancy In Urban Parks Within Metropolitan Landscapes, Mary- Esther Leblanc

Posters - 2026

Rapid urbanization is one of the most significant and accelerating drivers of global biodiversity change, reshaping wildlife communities by fragmenting habitat, altering prey availability, and introducing human disturbances. Despite these pressures, some wildlife species are attracted to and may even flourish in urban settings, primarily because urbanization creates an altered landscape that often unintentionally provides resources functioning as components of habitat. (Chiron et al., 2024) Raptors, as apex predators within avian food webs, offer a valuable lens through which to examine these dynamics. While raptor communities are broadly negatively impacted by urbanization, some species can thrive in urban areas. (Leveau …

Untangling G-Quadruplexes In Dna: The Effects Of Nucleotide Excision Repair, Jaidelin Alvardo, Abiageal Riley, Erick Morales Orrante, Raynne Malik

Posters - 2026

Nucleotide Excision Repair (NER) remo ves bulky DNA lesions that are attributed to UV irradiation, environmental mutagens, and chemo-therapeutic agents (Schärer, CSH Perspectives Biology, 2013). G4- quadruplexes are formed by four guanines hydrogen bonded together to form a planar ring, and stacking of the hydrophobic G quartets stabilizes the quadruplex structure Capra et al.,PLoS Computational Biology, 2010). A surplus of this structure is linked to genomic Instability and cancer development.

Prior studies indicate that because NER eliminates large lesions of DNA, there may be a link to the removal of G4-quadruplexes through Nucleotide Excision Repair (De Magis et al, Nature,2020). …

Mapping Sensory Landscapes: Distribution And Arrangement Of The Anterior Lateral Line System In Texas Catfish, Tatiana K. Flores, Ruben Tovar

Posters - 2026

Fish have a system of sensory organs known as the lateral line system. This system contains numerous mechanoreceptive neuromasts and electroreceptive ampullary organs (Northcutt et al, 2000). Neuromasts are small, hair-like structures located within canals in the lateral line system just under the fish’s skin and are open to the environment through small pores visible on its skin (Parker, 2025). Water flows into these canals through the pores which stimulates the sensitive hair cells, resulting in electrical signals sent to the fish’s brain. The brain interprets these signals and creates “images” of the fish’s surroundings, helping it to see even …

Does Habitat Predict Head Shape? A Comparative Geometric Morphometric Analysis Of Eurycea Spp., Sarah Flores-Garza, Alexa Miner, Gianna Montelongo

Posters - 2026

Subterranean environments impose strong selective pressures, including complete darkness and reliance on non-visual sensory systems. In Eurycea salamanders, these conditions are associated with traits such as reduced eyes and expanded head regions that improve sensory detection (Tovar et al., 2025). Subterranean species are often expected to share similar head shapes due to convergent evolution. However, not all species experience these pressures equally. Eurycea latitans is a polymorphic species that inhabits both surface and cave environments. Eurycea sp._NB is an obligate subterranean species, while Eurcyea sosorum is a surface species. This study tests whether habitat predicts head shape in Eurycea, or …

Polylactic Acid (Pla) Microplastic Toxicity In C. Elegans, Maria Gamez, Dana Farley, Chiara Maldonado, David Mares

Posters - 2026

• Microplastics (MPs, > 5 mm1) are an environmental pollutant that pose health risks to humans. • Primary MPs are created for direct use or plastic stocks, and secondary MPs are created when plastics in the environment break down over time. • Microplastic exposure can cause oxidative stress, metabolic disorders, immune responses, neurotoxicity, and reproductive issues2-3. • Polylactic Acid (PLA) is a biodegradable plastic used in everyday items, such as food packaging, and as a polymer in 3D printing. • PLA exposure to fish causes organ damage5 and C. elegans exposure to primary PLA MPs and UV-aged MPs reduced reproduction6-7 . …

Muscular Degeneration In Caenorhabditis Elegans By Microplastic And Chemical Exposure Through Locomotion Analysis, Juan Pablo Olvera Rodriguez, Angelica Cue-Leon, David Mares

Posters - 2026

We use Caenorhabditis elegans (C. elegans) as a model organism to investigate the effects of microplastic and chemical exposure on muscle structure and function.

• Microplastics (MP) are pieces of plastic less than 5 μm, and Nanoplastics (NP) are less than 1 μm. Microplastics are man-made pollutants and have been found in the environment and in the food and water sources, including drinks from plastic bottles (Hu, 2020). • Our work relates environmental contamination to potential biological consequences at the muscular level, providing insight into how pollutants may contribute to degenerative damage.

• Polystyrene (PS) MPs alone and combined with …

Analyzing The Effect Of Melatonin On B Cells' Expression Of Cd36, Caitlyn Pinaga, Gabriella Galdeano, Nayi Gonzalez, Emma Welsch

Posters - 2026

• B cells specifically target pathogens and proliferate to make a plasma cell and secrete antibodies when stimulated. They use glucose as a main energy source but can also use fatty acids. • CD36 is a glycoprotein involved in the transportation and metabolism of fatty acids. • B cells express CD36 in unusually high levels in autoimmune patients. It is unknown as to how this occurs. • Melatonin is a hormone produced in the pineal gland, commonly known for its function in regulating the circadian rhythm. • Melatonin is also known as a master cell regulator and is believed to …

Bird Population Response To Abiotic And Biotic Stresses In Urban & Restored Oak Savannah Habitat, Annabelle Ball

Posters - 2026

Birds are heavily impacted by urban development. Many experience habitat fragmentation and removal of food sources. However, other species can adapt to and even thrive in urban environments, thanks to certain tree species, bird feeders, and buildings. In North America, the house sparrow and the European starling are invasive species that benefit from urban environments (Bartelt, 2011; Fitzwater, 2014). Meanwhile, many habitats across the continent are experiencing restoration/rewilding efforts for the benefit of birds. One such habitat is the oak-savannah, which is characterized by 10-30% canopy cover and a mixture of prairie & woodland vegetation, supporting a high diversity of …

"I Need Help!": Can Ashwagandha Reduce Inflammation-Driven Oxidative Stress Without Inducing Cytotoxicity In Macrophages?, Caitlyn Pinaga

Posters - 2026

Ashwagandha has been shown to reduce inflammation in humans by lowering pro-inflammatory cytokines and oxidative stress markers, helping regulate immune responses. It is commonly used to support conditions linked to chronic inflammation, such as stress-related disorders, arthritis, and metabolic imbalance. THP-1 macrophages are a part of the body's immune response to inflammation. While they produce a lot of different responses to inflammation, one of them is the production of Reactive Oxygen Species (ROS). N-acetylcysteine (NAC) is established to be a powerful antioxidant and is used as a positive control. My study aims to understand how ashwagandha, a popular supplement, affects …

Saved From The Brink Of Collapse: Evaluating The Success Of The Sussex Kelp Recovery Project, Keagan Farrell, Kelly Swyers, Adan Vasquez

Posters - 2026

Kelp forests are vital to ocean health, they provide habitat, food, and nursery grounds for a variety of marine species. These forests support fisheries, improve water quality, and help to protect coastlines (Eger et al. 2024). The Sussex Kelp Recovery Project is a marine conservation effort aimed at restoring their kelp forests along the Sussex coastline in southern England. This area lost up to 96% of its forests mainly due to the fishing practice trawling. Trawling is used to gather large amounts of fish, while dragging a net at the seafloor (Our history 2026). The main goal of the Sussex …

The Effects Human Presence Has On Dolphins Within A Natural Lagoon Enclosure In Managed Care, Mario Martinez, Winter Saldaña

Posters - 2026

● Previous research looked into the overall behavior of dolphins in managed care using observations of location (Dudzinski & Hill, 2025).

● This study provides opportunities to investigate the effects of human presence on dolphin activity and space use (Lauderdale et al., 2022; Trone et al., 2005).

● Purpose - To determine if human presence affects dolphin behavior / spatial use of natural lagoon.

● H1: Dolphin clustering will be seen in the most Northern part of the lagoon and area associated with humans consistently (Melillo et al., 2009).

● H2: Higher activity levels will be observed during the “during” …

Exploring Base Excision Repair Using Gene Knockout, Gregory Guantos, Cailyn Brock, Kamily Visser, Dylan Vargas

Posters - 2026

•             Base Excision Repair (BER) fixes damaged 3DNA bases throughout the cell cycle by removing damaged bases and replacing either one nucleotide in short-patch BER or a short stretch of nucleotides in long-patch BER. (Hindi, 2021, Cellular and Molecular Life Sciences:CMLS)

•             4G-quadruplexes (G4s) are 4 stranded secondary DNA structures formed in guanine rich areas of DNA and RNA. (Rhodes, 2015, Nucleic Acids Research)

The URA3 plasmid was used as a PCR template to make a gene deletion construct, then yeast were transformed so APN1 was replaced by URA3. 2APN1 encodes a major DNA repair enzyme in yeast, and strains …

Exploratory Evaluation Of Handler Performance And Processing-Related Outcomes During Cattle Handling, Morgan Marquardt

Department of Animal Science: Dissertations, Theses, and Student Research

Animals have several critical roles in society, including the production of food and fiber, and companionship. Contact with animals has been shown to benefit human physical and mental health, yet little research has investigated the impact that humans have on animals. Handler skill may considerably affect the extent to which humans influence animal health and wellbeing, and this may be a critical consideration for animal agriculture. Objective assessment of cattle handler skill has received limited attention in the scientific literature, despite its importance to human safety and animal welfare. When compared to less skilled handlers, highly skilled cattle handlers may …

Fisheries Research Report No. 358 - Recreational Fishing For Blue Swimmer Crab In Cockburn Sound: Estimates Of Effort And Catch In 2024/25, Alissa C. Tate, Claire B. Smallwood, Eva K M Lai

Fisheries Research Reports

The Cockburn Sound Blue Swimmer Crab (Portunus armatus) fishery was reopened to recreational fishing in December 2024 following a 10-year closure. Monitoring was essential to assess fishing effort and catch for this species.

A boat ramp (bus route) survey at four key access points (Leeuwin, Woodman Point, Palm Beach, and Point Peron) and shore-based roving creel survey (Fremantle South Mole to Point Peron) were used to collect data from December 2024 to May 2025. These surveys provide estimates of fishing effort, total catch (kept and released), harvest and catch rates for Blue Swimmer Crab in Cockburn Sound.

A total of …

Investigating The Missense Mutation In Men1 At Amino Acid Position 331 Changing Asparagine To Isoleucine, Anika Prasad

Expo Student Presentations

2026 Spring Expo Online Poster Presentation

• Biological & Life Sciences