Biology
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Item Restricted Microplastic Settlement Across a Salinity Gradient in the Tar-Pamlico River(2025-05-01) Chan, ChristineMicroplastics are found in almost all ecosystems on Earth. They pose a threat to organisms through accidental ingestion, bioaccumulation, or by concentrating toxins, such as endocrine disrupters, in the water. While it is understood that rivers transport a great amount of microplastic to the ocean, microplastic movement and settlement in estuaries are not well understood. Increased salinity can increase the benthic accumulation of microplastics due to flocculation, where the ionic activity in the water causes microplastics and suspended material to form dense clumps that settle to the bottom of the water column. We collected surface and benthic samples across a salinity gradient (2-7) during two research cruises at the juncture of the Tar-Pamlico River and Pamlico Sound in April 2024. Our goal was to determine if increased surface salinity led to increased benthic microplastic concentration due to settlement. Microplastics were isolated and counted through a standard operating protocol that included wet peroxide oxidation, density separation, Nile Red dying, fluorescence microscopy, and ImageJ analysis with the MP-VAT2.0 macro. Sampling date and environmental conditions had a greater impact on microplastic concentration compared to salinity. I hypothesize that other factors, such as rainfall, speed of water flow, and proximity to developed areas, may have a greater impact on microplastic presence in the water column vs. the sediment in the Tar-Pamlico River. I found that there is higher plastic in the sediment of the Tar-Pamlico River compared to at the surface of the water column, aligning with other studies of microplastic in estuarine systems. These findings may guide future efforts to better understand microplastic dynamics in the Tar-Pamlico River and Pamlico Sound.Item Restricted Molecular Surveillance of Babesia sp. Infections in Lemurs of Madagascar(2025-05-01) Adams, Lulea DaiTick-borne diseases, particularly babesiosis, are an increasing health concern that threatens both wildlife conservation and public health. Babesiosis is caused by a tick-borne protozoan parasite from the genus Babesia that affects a wide range of vertebrate hosts. The parasite targets red blood cells, causing symptoms that can range from mild to severe and may lead to mortality. Evidence of Babesia infections in endemic lemur species in Madagascar is emerging. However, little is known about the ecology and epidemiology of Babesia in Madagascar’s endangered primate community. This study investigates the environmental and host factors that may affect the distribution of this parasite in sympatric lemurs, with a focus on location, seasons, and species-specific variation. Blood samples from eight lemur species across four sites were tested for Babesia using quantitative PCR. Overall, there was a 28% prevalence of Babesia infections across the sites. Prevalence was highest in Indri indri, Propithecus diadema, and Avahi spp. Understanding patterns of infection across species and environment supports insights into transmission dynamics and identifying vulnerable populations. These findings highlight the importance of disease surveillance in wildlife, not only to support the persistence of lemur populations but also to evaluate the risk of potential pathogen spillovers across species.Item Restricted Causes and consequences of timing of ornamental plumage molt and courtship in captive ruff sandpipers (Calidris pugnax)(2025-04-30) Moore, AmeliaRuff sandpipers (Calidris pugnax) are medium-sized Eurasian shorebirds extraordinary for their sexual dimorphism and lek breeding system. Ruffs possess a unique genetic polymorphism for male courtship behavior with three stable male morphs: Independents, Satellites, and Faeders. Independent males are identified by their darker ruff plumage, are dominant, and will defend their court on a lek. Satellite males have predominantly white ruff plumage and are tolerated on the courts of Independents and co-display alongside them on the lek. Faeders, the third male morph, are female mimics that do not display but are tolerated on courts and attempt to sneak matings. To document ruff molt progression in male ruff sandpipers, I noted the date that each male’s ruff and head tufts were fully grown and the date that each male’s ruff or head tufts began thinning, as applicable. Observations were made four days per week between April and June to identify the onset and duration (in days) of courtship behavior for each of the nine males. Our results will help us gain a deeper understanding of the intrinsic and extrinsic factors that trigger molt and courtship behaviors and lead to improved captive breeding programs for this species.Item Restricted Characterization of Ethanol-Induced Enhancement of Human Epidermal Growth Factor Receptor 2 Mediated Cardiotoxic Interactions(2025-05-06) Coates, TrinityTrastuzumab (TZB), a targeted therapy for HER2-positive breast cancer, is associated with cardiotoxicity driven by oxidative stress and disrupted autophagy. Ethanol, widely consumed among cancer patients, also induces cardiomyocyte damage through increased reactive oxygen species (ROS) and calcium dysregulation. This study investigates whether ethanol amplifies TZB-induced cardiotoxicity in HER2-overexpressing rat cardiomyocytes. We hypothesized that ethanol exposure exacerbates ROS generation, suppresses antioxidant enzymes such as heme oxygenase-1 (HO-1), Catalase, and Glutathione, and inhibits autophagy marker LC3B. H9c2 cardiomyoblasts were treated with ethanol (1%) for 24 hours and analyzed via immunofluorescence and western blotting. Ethanol significantly increased HER2 expression and decreased HO-1 levels, suggesting a potential mechanism for exacerbated cardiotoxicity. These findings provide novel insight into how ethanol may worsen the cardiac side effects of TZB and highlight the need for monitoring alcohol consumption in cancer patients undergoing HER2-targeted therapy.Item Embargo Dopamine Receptor Control of Collagen Transcription and Secretion: Relevance to Fibrosis, Health and Disease(2025-05-09) Vishwakarma, NandiniDopamine receptors (DRs) play critical roles beyond the central nervous system, influencing cardiovascular function and fibrosis. However, the impact of DR signaling on collagen regulation in cardiac fibroblasts remains poorly understood, specifically the direct and indirect effects on collagen transcription factors. SP1, SMAD3, and TCF21 are all important transcription factors, previously determined in Endothelin-1 (ET1), Angiotensin II (Ang II), and transforming growth factor beta-1 (TGFb-1) pathways for collagen synthesis and accumulation. This study aims to investigate the effects of dopamine receptor 1 (D1R) and dopamine receptor 3 (D3R) signaling on transcription factors mediated by these established collagen synthesis pathways in regulation of human fibroblasts, that are heavily involved in health and disease across the human body, especially the cardiovascular system. By elucidating the role of dopamine receptor signaling in regulating collagen transcription and secretion, this study will provide insights into novel cellular and nuclear mechanisms underlying fibrosis in cardiovascular disease. Moreover, since collagen regulation is critical for tissue remodeling, wound healing, and fibrotic disorders beyond the cardiovascular system, these findings may have broader implications for human health and disease.Item Restricted Investigating the role of miR-100a in nicotine-dependent behaviors and transgenerational mechanisms in Caenorhabditis elegans(2025-05-07) Dutta, Neesha KishoreNicotine, a psychoactive alkaloid found in tobacco, drives addiction by binding to nicotinic acetylcholine receptors (nAChRs), altering cholinergic signaling, and promoting receptor overexpression. The overexpression of nAChRs has been linked to drug dependence, making nicotine addiction a leading cause of preventable deaths worldwide, largely due to tobacco use and secondhand smoke exposure. The nematode Caenorhabditis elegans, with its conserved nAChR subunits and well-characterized nervous system, exhibits behavioral responses to nicotine similar to those in mammals, including tolerance, acute stimulation, withdrawal, and sensitization. These traits allow for it to be an ideal model for studying the molecular and genetic mechanisms of nicotine addiction. The role of miRNAs in regulating nAChRs, nicotine-dependent behaviors, and the epigenetic effects involved in transgenerational inheritance will be explored in this study, with a focus on miRNA inhibition of cel-miR-100a to knock down miR-100a implicated in addiction pathways. Behavioral assays demonstrate nicotine dependence, withdrawal-like effects, and transgenerational inheritance, with F2-generation worms, which are never directly exposed to nicotine, but exhibit increased locomotion on nicotine-free plates. Experimental protocols begin with the cultivation of synchronized C. elegans populations (F0 generation) and chronic (24-hour) exposure to 61.7µM nicotine in K-medium. Behavioral assessments are performed using the WormLab software, revealing changes in addiction-related behaviors and suggesting miRNA regulation of nAChRs as a key molecular mechanism. Statistical analyses, such as ANOVA and regression modeling, are further used to evaluate gene expression and behavioral data. These findings provide novel insights into the molecular and genetic basis of nicotine addiction, including its transgenerational risks, and could inform the development of miRNA-based therapeutic methods to combat nicotine dependence and its long-term risks.Item Restricted INVESTIGATING MITOCHONDRIAL METABOLISM IN HIGH-FAT DIET INDUCED FATTY LIVER DISEASE USING WESTERN BLOT ANALYSIS(2025-05-04) Adala, SarayuFatty liver disease (FLD) is the most prevalent liver disorder in industrialized nations. Although FLD is becoming more common as time goes on, there are no approved pharmaceutical treatments currently for the disease. The lack of approved pharmaceutical treatments makes it critical to understand the underlying metabolic defects contributing to disease progression. This study looks at how the disruption of mitochondrial fatty acid transport, through liver-specific knockouts of carnitine acylcarnitine translocase (CACT) impairs mitochondrial and peroxisomal metabolism, leading to liver toxicity. Mice were fed a high-fat, choline-deficient diet (CDAHFD) to induce fatty liver disease, and were treated with fenofibrate, which is a PPAR-α agonist that is known to enhance fatty acid oxidation. Western blot analysis was used to quantify the expression of proteins involved in mitochondrial function, fatty acid transport, and lipid storage. The western blot results are critical because they show how the CACT deficiency impairs mitochondrial fatty acid transport, leading to mitochondrial dysfunction, lipid accumulation, and energy stress. After analysis of the western blots, results do not provide insight indicating that CACT knockout mice show decreased mitochondrial function, leading to the progression of fatty liver disease.Item Restricted CD25 Plasticity in Monoclonal Regulatory T Cells: Implications for Regulatory T Cell Identity and Therapeutic Applications(2025-04-30) Sampson, NoahRegulatory T cells (Tregs) play a crucial role in immune homeostasis and suppression of autoimmunity. To investigate their therapeutic potential and gain deeper insight into their function and therapeutic potential, a monoclonal Treg population was generated through single-cell cloning. Peripheral blood mononuclear cells (PBMCs) were isolated from human donors, and CD4⁺ T cells were magnetically separated from CD8⁺ T cells before being expanded in culture with IL-2 and TGF-β. A limiting dilution method was used to obtain a monoclonal population. Flow cytometry analysis confirmed that the cloned Treg line (2G4) exhibited key markers of regulatory function, including CD4, FOXP3, and CD25, with an increased expression of CD25 compared to the parental polyclonal line (Cardio-1). Interestingly, CD25 expression within the 2G4 clone showed a bimodal distribution, suggesting that CD25^high and CD25^low states represent interconvertible phenotypes rather than fixed, terminally differentiated T-cell subsets. This plasticity reflects a dynamic response to environmental cues and challenges the traditional view of CD25 as a static Treg marker. These findings support the value of monoclonal Tregs as a controlled and reproducible model for studying regulatory function and advancing cell-based therapies.Item Restricted Investigating the role of microRNAs on the transgenerational effects of nicotine using Caenorhabditis elegans(2025-05-01) Woollen, Victoria RoseThis project aims to investigate the effects of nicotine, the highly addictive and toxic substance in tobacco-based products, has on offspring (1st and 2nd generations, F1 and F2) using the model organism Caenorhabditis elegans (C. elegans). C. elegans are microscopic nematode worms that are used as a model organism to study epigenetic effects passed down through generations. Due to their transparency, small size, and cellular simplicity, researchers can easily observe the internal structures and processes of C. elegans. To characterize nicotine-dependence, our lab looks at three behaviors: stimulation, adaption, and withdrawal. We hypothesize that maternal nicotine exposure (F0 generation) increases susceptibility to nicotine dependence in F1 and F2 generations. To test this, F0 worms were exposed to a 61.7 µM nicotine solution or a vehicle control (K medium) at the L3 larval stage for 24 hours, then the behaviors were observed in F0, F1, and F2 generations, where the F1 and F2 generations were not exposed to nicotine. Locomotion behaviors were analyzed using WormLab. For nicotine-exposed worms, an increased speed in a nicotine-free environment indicates withdrawal, while a lower locomotion speed in nicotine-containing environment indicates nicotine adaption. To explore miRNA-mediated molecular mechanisms, RNA interference with the miRNA inhibitor anti-cel-miR-1 will knock down miR-1, which regulates nicotinic acetylcholine receptor (nAChR) expression. Behavioral changes in miRNA inhibitor and nicotine co-treated worms will be compared to nicotine-only treated worms and vehicle controls. Statistical analyses of locomotion behaviors revealed transgenerational inheritance of nicotine-dependent behaviors and the important role of miRNA-1 in nicotine-dependent behaviors. With miR-1 inhibition in F0 generation, the nicotine-dependent behavior was cured in F0 and the following F1 and F2 generations. This represents an important finding in the mechanism of nicotine-dependent behaviors and potentially applies to the development of future miRNA-mediated therapeutic strategies.Item Restricted Exploring Patient Perspectives Through Visual Research(2025-05-02) Watson, Calissa BrookeWhen discussing the major conflicts and public health concerns regarding oral health, one of the main subjects is dental caries in youth. Dental caries is the most common chronic disease among children ages 6-10 years old (CDC). Between the years 2015 and 2016, 45.8% of youth aged 2-19 years had caries (CDC). Of those individuals, the prevalence increased with age. Not only do these youth have caries, but a fraction of the caries are left untreated. 13.0% of youth aged 2-19 years had untreated caries in the primary or permanent teeth (CDC). When analyzing data associated with dental caries in youth and the federal poverty level, it is shown that dental caries increase in youth from families living below the federal poverty level. Preventive care is necessary in preventing dental caries and preventative care can start during the mother’s pregnancy. However, in some cases, this is not occurring and is negatively impacting the mother’s oral health as well as the infants. This research relies heavily on the voices of those being impacted (the pregnant women or mothers of infants) and those who treat the women (health care providers). Photovoice as well as interviews is the main form of gaining qualitative data. Photovoice is a visual research methodology that allows participants to document and present their concerns in vulnerable communities. Participants are able to find their voice through the use of photos. The finalized research will be able to thoroughly discuss the barriers between pregnant women and oral health. The main objective of this research is to understand how social determinants of health (Social and Community Context, Economic Stability, Education Access and Quality, Health Care Access and Quality and Neighborhood and Built Environment) impacts prenatal dental care. This data will help identify barriers and disparities in access to prenatal dental care, inform targeted interventions to improve oral health outcomes for pregnant individuals and their offspring, and guide policy recommendations to enhance equitable healthcare access.Item Embargo MOVEMENT AND HABITAT USE OF A RESIDENT KING RAIL (Rallus elegans) POPULATION AMONG MANAGED IMPOUNDMENTS AND TIDAL MARSHES IN COASTAL SOUTH CAROLINA(East Carolina University, May 2025) Linke, Megan MichelleFreshwater wetlands are important habitat for a variety of waterbirds. However, inland wetlands have sustained significant losses due to marsh drainage and land conversion for agriculture and human development. This loss of habitat has led to declining populations throughout the Eastern United States for an obligate freshwater marsh specialist, the king rail (Rallus elegans). Loss of inland habitat has pushed king rail populations toward the coastal margins of their range, where they are increasingly exposed to climate change related assaults such as hurricanes and associated storm surge, tidal inundation, and saltwater intrusion. To support habitat restoration and management efforts for a coastal king rail population, I investigated king rail movements and habitat use across a series of natural and impounded wetlands, interspersed with riparian forest along a tidally influenced river in coastal South Carolina. Some impoundments were managed for wintering waterfowl by planting fields with Carolina Gold rice during the king rail breeding season. Using VHF radiotelemetry, 13 king rails were tracked over the course of this two-year study generating Autocorrelated Kernel Density Estimated (AKDEc) home ranges. Breeding season 95% AKDEc was 5.1 ± 2.4 ha with a core 50% AKDEc of 1.1 ± 0.5 ha. Non-breeding season 95% AKDEc was 4.0 ± 2.3 ha with a core home range of 1.0 ± 0.5 ha. No significant difference was observed between the size of the breeding and non-breeding home ranges, and the size of home ranges observed here were smaller than other reported home ranges, suggesting the possibility of high prey and/or high king rail densities. Shifts to distinct non-breeding home ranges were observed between May and July and were preceded by either the successful molting of an instrumented individual’s chicks, nest failure, or habitat disturbance through management within the home range. Individuals that were heavier upon capture were more likely to occupy the same home range throughout the year, staying on the breeding home range for the non-breeding season. During the 2024 breeding season, king rails used habitat closer to channels in areas with higher percentages of marsh vegetation. Dominant vegetation types included giant cutgrass (Zizaniopsis miliacea), smartweeds (Polygonum ssp.), sedges (Carex ssp.), coffeeweed (Sesbania herbacea), and primrose willow (Ludwigia peploides). King rails continued to use areas within their established home range if it had been treated with herbicide, as the dead vegetation likely provided the same habitat characteristics as it did when it was alive, and the rails were already established in the area. A stem count measurement revealed that king rails avoided the densest marsh vegetation and selected areas with more moderate densities. My results suggest that when managing impoundments for king rails alongside wintering waterfowl, it is important to provide vegetation along channels and irrigation ditches within rice fields to provide cover while king rails forage along the edges of the channels. The removal of vegetation when planting rice and during dike construction reduced the likelihood for king rails to stay on their breeding territories and resulted in some individuals fleeing the area. Management techniques to control the density of emergent vegetation such as prescribed fire may be useful to keep a moderate density on the landscape.Item Embargo Ecdysone Receptor modulates EGFR signaling for timely cyst packaging in Drosophila germ cells(East Carolina University, May 2025) Swain, Lindsay AdelleOocytes are packaged into ovarian follicles, each containing a maturing germ cell surrounded by a layer of somatic cells that secrete protective eggshell and chorion proteins. This conserved arrangement is essential for proper oocyte development and reproductive success. Continuous coordination and bi-directional signaling from somatic cells to germ cells is necessary for proper oocyte packaging. In Drosophila, although germ cell packaging was presumed to be largely controlled by somatic follicle cells enveloping passive germ cells, recent studies suggest that germ cells themselves produce motor forces that drive somatic encapsulation. Here, in support of this hypothesis, we present data suggesting that cyst encapsulation is dependent upon Ecdysone Receptor, a steroid hormone receptor known to control multiple aspects of oogenesis. Using tools to deplete EcR levels or block transcriptional activation specifically in the germline, we show that germline-autonomous EcR is necessary for the timing of cyst encapsulation. In the absence of EcR, germ cell encapsulation is slowed, resulting in increased incidence of cyst collision events in the germarium. EcR facilitates germ cell cyst encapsulation by signaling somatic cells to promote proliferation, organize escort cell projections, and intercalate stalk cells. We show that an increase in germ cell cortical contractions is sufficient to rescue cyst collisions. Finally, we conclude that EcR is likely acting with EGFR signaling to modulate escort cell activity. Overall, these data suggest that in addition to its well-characterized roles in somatic follicle cells, EcR is necessary in the germline to promote timely ovarian follicle assembly and development.Item Open Access Habitat selection, prescribed burn effects, and passive monitoring of Eastern black rails (Laterallus jamaicensis jamaicensis) in North Carolina(East Carolina University, December 2024) Kephart, Bailey A.Eastern black rail (Laterallus jamaicensis jamaicensis) populations have experienced rapid declines from habitat loss exacerbated by sea level rise and human development. The suitable habitat for this species is broadly described as marsh containing dense, herbaceous vegetation at high elevations with little to no standing water (~ 0-5 cm). However, habitat characteristics, such as vegetation species composition and hydrology, vary by location where black rails are found. In North Carolina, birds are concentrated in only a few areas of coastal marsh that are subject to erosion and likely to be lost within the century. Additionally, this species’ behavior and phenology is poorly understood. As the black rail faces threats of extinction, it has become increasingly vital to better understand the species’ activity patterns and identify viable management strategies to facilitate marsh migration away from the shoreline and preserve existing populations. Prescribed fire may be a useful tool for maintaining patches at an early-successional state and promoting quality habitat, but its effectiveness has not yet been assessed for the mid-Atlantic coastal plain. In Chapter 1, I identify and discuss characteristics of suitable habitat as they relate to burn management and the probability of black rail occupancy. I conducted callback surveys during the breeding season at sites that were either burned in mid-winter or left unburned in 2022. I created occupancy models to identify predictors of suitable habitat. In separate analyses, I directly compared these variables among sites left unburned, within one year of burn, and one-year post-burn. These results were then integrated to assess the effects of prescribed fire management on black rail habitat and the effect of burn status on habitat use. In Chapter 2, I uncover temporal patterns of vocal activity and propose a phenological timeline for black rails in coastal North Carolina. I used passive monitoring techniques to document aspects of phenology and behavior during the breeding season. During 2023, I deployed recording units and monitored water levels at Cedar Island NWR. Lunar illumination values were extracted for each hour that was recorded. Counts of verified detections (3-second segments of recordings of black rail vocalizations) were then incorporated into models that identified temporal predictors of 1) vocalization probability and 2) counts of call segments during active periods. Predictors of vocalization probability were assessed separately from estimated counts. Over the 2-year period, I deployed motion-activated trail cameras at locations where black rails were detected to uncover evidence of phenology and breeding activity. I captured evidence of a presumed immature black rail after the completion of its juvenile molt. This 2022 observation is the first record of confirmed breeding by black rails in North Carolina in over 120 years. Results of this project provide insights into habitat preferences, vocalization patterns, and breeding phenology of Eastern black rails in North Carolina.Item Open Access Nutrient effects on soil fungal communities in a coastal plain wetland ecosystem(East Carolina University, December 2024) Siebor, Scott WyattAnthropogenic influences such as urbanization and intensive agriculture practices modify nutrient and water cycles in significant ways. These activities can cause disruptions to microbial mutualisms, especially in low-nutrient wetland ecosystems. Due to ongoing alterations to nutrient and moisture variations, the composition of fungal microbe communities may be shifting in unexpected ways. In this study, I investigated how long-term fertilization, and hydrologic alterations affect soil fungal microbial communities in a historically low-nutrient coastal plain wetland. I hypothesized that long-term fertilization and varying water conditions through ditching influenced patterns in fungal communities to different degrees. I tested this hypothesis at a long term nutrient addition (N-P-K fertilizers) and disturbance (mowing) experiment (established in 2003) located at East Carolina University's West Research Campus in Greenville, North Carolina. I specifically examined fungal microbe communities (based on amplicon sequencing of the internal transcribed spacer (ITS) region between the small and large subunits of the ribosomal RNA gene) in mowed plots undergoing and not undergoing nutrient enrichment. Results revealed that nutrient enrichment and ditch effects influenced fungal community composition, with community evenness being higher in wetter, unfertilized soils than drier fertilized soils over time. Additionally, soil treatments were more strongly associated with specific subsets of less abundant fungal families.Item Embargo The Influence of a Digital Weight Loss Intervention on Blood Pressure Outcomes(East Carolina University, July 2024) Maloney, Kallie R. StephensCardiovascular disease remains a highly prevalent disease that is consistently among the leading cause of death for Americans (Ahmad, 2023). Managing one’s blood pressure is a prominent recommendation in preventing heart disease (Olsen et al., 2016), but over 45% of the US population is classified as having hypertension (Benjamin et al. 2019). While the treatment recommendations for hypertension depend on hypertensive stage and ASCVD risk, lifestyle modification is recommended for all. Typical lifestyle changes include weight loss, diet modification, and increased physical activity (Whelton et al., 2018). Lifestyle intervention is not without challenge, however, with physician time constraints consistently emerging as a barrier to implementation. Digital health provides an avenue for assistance with lifestyle modification, something recognized by a majority of physicians (AMA, 2022). Digital health has shown to be effective in managing various physical health outcomes, including weight loss and diet modification. Little research, however, has focused on hypertension specific goals. Digital health also serves as an opportunity to reach underserved populations, such as those from rural or low-income environments. Preliminary research indicates that digital health interventions are feasible in these populations, but little research has assessed blood pressure outcomes. The aims of the present study, therefore, were to assess the influence of a commercially available digital health intervention for weight loss, Noom, on blood pressure related outcomes, determine what factors influence blood pressure, and determine if rurality and income environment influences rate of blood pressure decrease. It was hypothesized that systolic and diastolic blood pressure would decrease over the 16-week intervention. It was also hypothesized that weight, gender, and physical activity (steps) would be associated with blood pressure. Lastly, it was hypothesized that both rural users and users living in environments with a higher proportion of individuals from low income would display slower blood pressure decrease. User’s weekly blood pressure, weight, and steps were utilized for analysis. User zip codes were used to classify users as rural or urban using secondary Rural Urban Commuting Codes. Zip codes were also utilized to estimate the proportion of individuals from low-income households (<$25,000 annually) within a user’s zip code using 2019 IRS tax data. From there, conditional growth curve models were estimated to address all hypotheses. Systolic and diastolic blood pressure significantly decreased over the 16-week intervention. Baseline weight and physical activity were significantly associated with systolic blood pressure. Lastly, rurality status and income environment were not significantly associated with different systolic or diastolic blood pressure trajectories. While many findings were as expected, rurality and user’s environmental income not significantly slowing rates of blood pressure decrease were surprising. It is possible that the present sample of Noom users do not adequately reflect the average rural individual, or individuals from low income environments. Specifically, the cost associated with Noom and the voluntary nature of inputting blood pressure could have contributed to a sample that was more motivated for blood pressure change.Item Open Access Routes of transmission of gut bacteria in R. imitator tadpoles in an experimental context(East Carolina University, July 2024) Belduque Correa, NataliaThe gut microbiota provides important capacities for the host, and the relationship between host-microbiome could affect, bidirectionally, different traits of the history life. Therefore, it is important to know how the microenvironment of living beings is shaped and what factors influence the community and composition of bacteria. The mother–to–offspring microbiota transmission has been extensively studied in vertebrates, focusing on human primates. In amphibians, the understanding of diversity and community of bacteria has been biased to skin microbiome. In this research, we study whether R. imitator mothers, a neotropical poison frog from Peru that display prolonged parental care, are transferring microbes to tadpoles by feeding them with trophic eggs. We used 16S rRNA amplicon-sequencing of the gastrointestinal tract of captive R. imitator mothers and their tadpoles. The analyses showed that composition of microbes is different between parents and offspring. Also, the composition of gut bacteria of tadpoles included different bacterial phyla usually found in gastrointestinal tract of vertebrates. Although, phyla Bacteroidetes and Proteobacteria were also found in gut of fish food experiment, it was seen that the proportion of Proteobacteria are higher in tadpoles from switching and control experiments, which can suggest that the proportion of microbes that comes from the maternal diet is similar than the proportion that comes from the environment. This supports the assumption of mother’s role in parental care is not limited, exclusively, to provide nutrient resources.Item Embargo Nitrogen and Phosphorus Remediation in Mesocosm Floating Treatment Wetlands receiving Municipal and Aquacultural Wastewater(East Carolina University, July 2024) Barnes, Matthew ThomasAs populations shift and grow throughout the world, the amount of organic waste generated directly and indirectly by humans has increased. Wastewater treatment operations play a key role in helping to keep our natural surrounding water bodies clean by removing nitrogen (N), phosphorus (P), and other contaminants of concern from wastewater. Floating treatment wetlands (FTWs) may offer a low-cost energy efficient supplemental treatment option to existing wastewater treatment operations by removing nutrients from wastewater through plant uptake, adsorption, and microbial processes. The purpose of the study was to determine the N and P reduction capabilities of mesocosm FTWs from both domestic and aquaculture wastewater. The extent to which FTW plant species diversity (monoculture vs polyculture) influenced N and P removal was investigated, and the N and P removal dynamics throughout the growing season were characterized. Water samples and plant measurements were collected every week over the course of 14- and 10-week trials during 2022 and 2023, respectively. Mesocosm FTWs were located at the Greenville Utilities Commission Wastewater Treatment Plant for domestic wastewater research and the Marine Aquaculture Research Center of North Carolina State University for aquaculture wastewater research. For both trial 2 studies of the MARC and GUC-WWTP, there were no statistically significant differences among treatments of nitrogen (N) or phosphorus (P) removal. However, for all trials N was removed more effectively than P. The GUC-WWTP had removal ranges of 0.12 to 0.32g/m2/day for N and 0.01 to 0.08 g/m2/day for P. The MARC trial 1 had removal ranges of 0.49 to 0.95 g/m2/day for N and 0.02 to 0.04 g/m2/day for P whereas the trial 2 study has removal ranges of 0.21 to 0.43 g/m2/day for N and 0.004 to 0.02 g/m2/day for P. Overall, the late summer growing season (MARC 1) had higher nitrogen removal rates compared to late spring and early summer (MARC 2). For the GUC-WWTP, there was more phosphorus removed compared to the MARC, for trial 2. Yet all achieved positive removal rates in summation of both locations. The purpose of this study was to characterize the N and P removal efficacies of monoculture vs mixed species plantings of floating treatment wetlands from wastewater. Additional research into native wetland plant species and their nutrient removal potential could aid in finding alternatives or supplements to high energy-dependent treatment methods at wastewater treatment facilities. Future studies should investigate how water hydraulic retention times, continuous flow vs batch systems, and seasonal plant growth characteristics impact nutrient removal efficacies. Other studies into plants with more P removal efficacy and plants with more nutrient specific uptake rates could be effective depending on the nutrients being removed.Item Open Access Identification of a novel autonomous role for Ecdysone Receptor during Drosophila ovarian germ cell differentiation.(East Carolina University, July 2024) Jung, Lauren ElizabethA tightly regulated network of signals coordinates the division of Drosophila germline stem cells (GSCs) and differentiation of their daughter cells to produce viable oocytes. The steroid hormone, ecdysone, is known to promote GSC self-renewal; however, due to lack of compatible genetic tools, potential autonomous roles in the germline have not been fully evaluated. Ecdysone elicits a diverse array of transcriptional responses by binding to a heterodimeric complex composed of Ecdysone Receptor (EcR) and Ultraspiracle (Usp). To elucidate whether EcR facilitates autonomous reception of ecdysone in the germline, we built germline-compatible genetic tools to manipulate EcR levels or activity. Depleting EcR mRNA or loss of EcR ligand binding in the germline caused a loss of GSCs over time, demonstrating that it is necessary for GSC self-renewal. Further, over-expressing either EcR.A or EcR.B1 isoforms resulted in undifferentiated germ cell tumors and decreased numbers of GSCs. This is a ligand-dependent function of EcR, as over-expression of EcR that cannot bind ecdysone suppressed tumor development. By restricting over-expression to later stages of the germline, we found that EcR is sufficient to induce tumors only when over-expressed in the GSCs and early daughter cells. In tumorous ovaries, stem-like cells were also identified outside of their normal stem cell niche, suggesting that these cells remain competent to respond to BMP signals. Using single-cell RNA-sequencing to compare EcR over-expressing and Tkv over-expressing ovaries, we found remarkably similar transcriptomes in heterogenous populations of germ cells. These data suggest that EcR promotes differentiation of germ cells by directly regulating components of the BMP signaling pathway and that low levels of EcR expressed in wildtype GSCs are sufficient for ligand-dependent activation of an ecdysone-responsive transcriptional program. Altogether these data reveal a novel, autonomous role of EcR in GSC maintenance and regulation of differentiating daughter cells.Item Open Access Examining Microbial Transfer Between Human and Non-Human Primates Using a One Health Approach(East Carolina University, July 2024) Smith, DejahThe health of humans, wildlife, plants, and their environments are interconnected, and this concept is fundamental promoting public health and conservation goals globally. The One Health approach defines the relationship of humans, plants, animals and our shared environments, positioning health at the core. This approach aids conservation management as facilities can look at health holistically, focusing not only on the health of the captive populations but also of the staff, volunteers, and the public. This is particularly important for the conservation of endangered species, such as lemurs. In Madagascar, lemur populations represent 20% of the worlds primate species and are endangered due to habitat fragmentation, deforestation, and anthropogenic factors. Captivity gives endangered populations a chance at rehabilitation and humans the opportunity to observe and learn from their behaviors, physiology, and development. Although captivity holds many benefits, we must think about how factors introduced by conservatory settings influence the health of captive animals and the humans who interact with them. Past studies have documented the transfer of microbes is documented to occur between humans and their pets. In this study, I examined the extent to which microbiome exchange occurred between human and non-human primates observed at the Duke Lemur Center (DLC) in Durham, North Carolina, USA. I hypothesized that (i) lemurs exposed to human microbiomes frequently (i.e., daily) and housed in captive only settings will exhibit altered gut microbial compositions and higher microbial diversity of human associated taxa than free-ranging lemurs that interact rarely with humans and maintain spatial proximity or no human contact. I also hypothesized that (ii) humans working in Duke Lemur Center departments with high levels of contact between NHPs will harbor an altered skin microbiome, composed of bacterial taxa associated with lemur species. To test this hypothesis, I collected fecal samples from four lemur populations, which included blue-eyed black lemurs (Eulemur flavifrons), Coquerel’s sifakas (Propithecus coquereli), crowned lemurs (Eulemur coronatus), and ring-tailed lemurs (Lemur catta). This research was approved by the East Carolina University’s Institutional Animal Care and Use Committee (IACUC) protocol number: AUP#P110. Human forehead and hand skin swab samples from 13 interns over five timepoints were provided voluntarily from the DLC summer interns who worked in various departments across the facility. These protocols were approved by East Carolina University’s Intuitional Review Board (#UMCIRB 22-000802). The gradient of lemur-human interaction intensity across DLC department was done to ensure a variety of frequency of interaction with the lemur populations. There were seven husbandry interns, four research interns, one education intern and one paleo-primatology intern. I extracted genomic DNA from human skin and lemur fecal samples and conducted 16S rRNA gene PacBio HiFi long-read sequencing. Results showed that human-associated taxa were observed to a greater extent in the gut microbiomes of enclosed lemurs where there was more frequent contact with humans. Variation in diversity was observed in the free-ranging, terrestrial population, Lemur catta, who I observed in the field as approaching gated areas and trails that people often occupied. In human forehead samples, taxa associated with the phylum Bacteroides were observed. Both lemur fecal samples and human skin samples harbored Bacteroides, demonstrating the presence of non-endemic microbes in lemur guts. In humans, this revealed that animal caretakers can exhibit altered microbial diversity due to contact intensity with lemurs since taxa from the Bacteroides phylum were observed in high relative abundance on the human skin microbiome of the animal husbandry interns only, which is contrary to past studies. Understanding the mechanisms of microbiome transmissions among humans and non-human primates is especially important for the conservation of captive non-human primates and the health of the humans managing captive populations. Transmission of microbes among humans and non-human primates can provide key information on how to best serve these captive populations and manage facilities to ensure the best outcomes for rehabilitation and conservation of species.Item Open Access Chronic Low Dose Toxicity of Acrolein in C. elegans Mitochondria(East Carolina University, July 2024) Yan, LisaAcrolein (ACR) is a chemical of interest in the pathology and progression of mitochondrial disease and disorder. Chemical exposure to ACR may occur exogenously due to the use of herbicides or burning of fossil fuels, or endogenously as a by-product from various metabolic pathways. Several studies focus on the impact of high dose acute exposure of ACR with various model organisms, including live rats and mice, human spermatozoa, and several cell culture models. These models do not address the consequences of long term or chronic, low dose exposures and impacts on progeny. For these reasons, the model C. elegans was ideal because of its established genome, ability to self-fertilize or sexually reproduce, ability to yield three hundred progenies in its lifetime, and its short and understood lifespan. We hypothesized that C. elegans would experience mitochondrial dysfunction when chronically exposed to low doses of ACR, particularly with the 15 μM concentration. Based on previous research indicating another electrophilic aldehyde, 4-hydroxynonenal (4-HNE) inhibits SDH activity by forming a protein adduct with the redox subunit of SDH, we predicted that ACR may inhibit complex II (SDH) activity through protein adduct formation. We also predicted that ACR may also decrease lifespan and fecundity across generations of nematodes. To test our hypothesis and aims, we utilized C. elegans in experiments incorporating lifespan and fecundity assays, performed a histochemical stain to qualitatively measure SDH activity, used RT-PCR targeting specific genes related to oxidative stress and SDHA-1, and attempted to isolate mitochondria to perform SDH activity assays measured with spectrophotometry. Our results from the lifespan and fecundity assays suggested that low dose, chronic ACR exposure may decrease lifespan and fecundity in C. elegans. We also learned that C. elegans will attempt to leave the agar plate at ACR concentrations of 75 μM and 100 μM. Our RT-PCR results showed an upregulation in SDHA-1 and SOD-3 transcription in C. elegans after a 24-hour exposure to 100 μM ACR. These results suggest that higher doses of ACR may cause oxidative stress or damage to the mitochondria and SDH. Further experimentation may help better determine the interaction between ACR and the flavonoid subunit of SDH.