Biology Commons^™

The Old Family Clock: Exploring High Variation Of Chronotype In The Common House Spider, Parasteatoda Tepidariorum, Caitlin Jones

Electronic Theses and Dissertations

Circadian rhythms are often tightly confined around a mean of 24 hours with little variation in traditional model organisms in the absence of environmental time cues. Some spider species fall well outside this normal range with mean periods of 18 hours and variation around these means of 6 hours or more. This extreme variation in circadian rhythm is not well-understood and is the focus of the current study. Using Parasteatoda tepidariorum as a model organism, we investigated whether variation in eight circadian parameters could be explained by genetic variability, environmental conditions, or an endogenous feature of the circadian system of …

Mapping The Binding Site Within Integrin D2 For Carboxyethylpyrrole (Cep)-Modified Proteins, Afia Prema

Electronic Theses and Dissertations

Neutrophils and macrophages accumulate at sites of inflammation and cause chronic inflammation leading to various diseases. Therefore, to better understand chronic disease pathways it is important to investigate the properties of macrophage accumulation in inflamed tissues. The I-domain of the macrophage receptor integrin a_Db₂ plays a vital role in macrophage retention by binding to CEP (carboxyethyl pyrrole), a ligand available at inflammatory sites. This thesis mainly focuses on evaluating the binding site within integrin a_Db₂ that binds carboxyethyl pyrrole (CEP)-modified proteins. So, a recombinant plasmid construct containing the integrin I-domain was developed. Seven non-conserved …

Microsporidian Spores And The Integrin Binding Loop Of The Madam Protein Are Important For Integrin Signaling And Attachment To Host Cells, Cindy L. Barrett

Electronic Theses and Dissertations

Microsporidia are a distant fungal pathogen that have severe clinical consequences for the immunocompromised. Previous work identified a microsporidian pathogen protein termed Microsporidian ADAM or MADAM. This protein has close sequence homology to other ADAM proteins (A Disintegrin and Metalloproteinase) in two microsporidian species, Encephalitozoon intestinalis and E. cuniculi. ADAM proteins have a wide range of functions, including binding to integrins and host signaling. It is known that many pathogens manipulate integrins to invade host cells, and it is predicted that microsporidia are also exploiting this host target. Previous work with the MADAM protein demonstrated that this protein has a …

Femoral Osteohistology In American Alligators (Alligator Mississippiensis) Reveals High Variation In Growth And Facilitates Interpretation Of An Early Pliocene Alligator, Davis Gunnin

Electronic Theses and Dissertations

Histological analysis of long bone thin sections is commonly used to infer growth rates and ecology of extinct vertebrates, particularly within Archosauria. However, most comparative neontological studies have used small samples of captive individuals, limiting the scope of variation. To fill this gap, 44 femoral thin sections of wild Alligator mississippiensis were prepared and analyzed. Comparison of slides revealed that larger individuals from cooler climates tend to show more LAGs compared to southerly A. mississippiensis of similar size, however, there is considerable variation. This pronounced variation in wild specimens emphasizes the need to use caution when interpreting paleohistological data with …

Understanding The Role Of Sabp2-Interacting Protein (Sip) 428: An Nad+-Dependent Deacetylase Enzyme In Abiotic Stress Signaling Of Nicotiana Tabacum, Mariam Onabanjo

Electronic Theses and Dissertations

Abiotic stresses are constantly rising and pose a very high risk to global agricultural productivity and food security. Some plants have evolved several innate pathways for defense against these stresses. Hence, understanding stress signaling pathways can help develop crop plants with higher stress tolerance. The salicylic acid-mediated signaling pathway is important in plants experiencing biotic and abiotic stresses. In previous studies, SABP2-Interacting Protein (SIP-428) has been shown to be a negative regular of plant growth under abiotic stress. This study aimed to investigate the roles of SIP-428 in the ROS signaling of tobacco plants. We investigated transgenic RNAi-silenced lines of …

Investigation Of The Protein Components In A Periplasmic Mechanism Regulating Bacterial Morphology, Alexandra Pulliam

Electronic Theses and Dissertations

Salmonella is a leading bacterial cause of foodborne illness worldwide. During a previous study investigating the enzymes responsible for regulating cyclic-di-GMP concentrations, a mutant in the cyclic-di-GMP-specific phosphodiesterase STM3615 was identified that displayed a phenotype characterized by decreased survival on agar plates and a shorter bacterium length. I was able to determine that the periplasmic domain of STM3615 was responsible for this phenotype, not the enzymatic phosphodiesterase domain. Based upon a bioinformatic analysis of the protein, I then hypothesized that the periplasmic domain of STM3615 was interacting with a periplasmic protein to give rise to this phenotype. To identify this …

Characterization Of Molecular Content, Cytotoxicity, And Anti-Inflammatory Activity Of Extractions From Eupatorium Serotinum, Jordy Sloan

Electronic Theses and Dissertations

Inflammation is a complex and varied immune response which can be expressed chronically or as a temporary reaction to foreign invaders. Symptoms of inflammation include swelling, pain, soreness, and difficulty of motion. Recently, the effect of sesquiterpene lactones such as Helenalin from Arnica montana have been studied for their anti-inflammatory properties. In this study, we identified and harvested samples of Eupatorium serotinum, a plant historically used by Native Americans to treat a variety of medical illnesses. Crude extracts of the leaves, flowers, roots, and stems were prepared by ethanol extraction. The cytotoxicity of the different extracts on HEK293 cells …

Dolphin Behavioral Responses To Uncrewed Aerial Systems As A Function Of Exposure, Height, And Type, Savannah Damiano

Electronic Theses and Dissertations

Uncrewed aerial systems (UAS) are becoming a standard tool in the study of cetaceans, however, a comparative assessment of animal responses to UAS has not been established to gauge the most effective systems for cetacean study. We utilized Dolphin Quest Bermuda’s eleven bottlenose dolphins as subjects for such an investigation taking place over five weeks in 2022 and five weeks in 2023. The dolphins were evaluated for investigative behavioral responses to six off-the-shelf UAS types and a custom fixed wing system. Each UAS was flown in decreasing height vertically above the main dolphin lagoon to evaluate dolphin behavioral responses in …

The Evolution Of Empathy: Through The Lens Of A Rodent Model., Caroline Driscoll-Braden

Electronic Theses and Dissertations

Empathy is the capacity to be affected by and share the emotions of others, to discern the circumstances prompting another’s emotional state, and to identify with another by adopting their perspective. Research investigating the empathically motivated behavior of rats can help inform the evolutionary history of empathy and provide additional support of the continuity of empathy in animals and humans. In this dissertation, I examine the helping behavior of rats to explore the complexities of rodent empathy. In Chapter I, I review the multiple layers of empathy and describe both historical and contemporary research examining empathy in non-humans. I explain …

Transmission And The Evolution Of Diseases Caused By Chlamydia Trachomatis, Sars-Cov-2, And Plasmodium Species., Nathan Steffens

Electronic Theses and Dissertations

Principles of natural selection have proven valuable for explaining why pathogens cause the diseases that they do. In theory, the evolved level of host exploitation should reflect how dependent a pathogen is on host health for transmission. This dependency is shaped by transmission mode and transmission opportunity, which should therefore be predictors of disease manifestations. In this dissertation, I apply these principles to investigations of depression in Chlamydia trachomatis and virulence of SARS-COV-2 and Plasmodium species. This dissertation has five chapters. In chapter I, I describe the theoretical foundation of my dissertation research. I also briefly introduce each study system. …

Neonate Atlantic Sharpnose Shark (Rhizoprionodon Terraenovae) Relative Abundance And Body Condition In Two South Carolina Estuaries Varying In Urbanization, Rileigh E. Hawk

Electronic Theses and Dissertations

Urbanization near estuaries has been shown to affect the growth and survival of juvenile sharks using the system as a nursery. North Inlet and Murrells Inlet, South Carolina, are similarly-sized, tidally-dominated, bar-built estuaries with extensive Sporobolus-lined tidal creeks but differ in degree of human impact. Previously, Murrells Inlet was shown to have a lower abundance and diversity of large sharks than North Inlet and Atlantic Sharpnose Sharks (Rhizoprionodon terraenovae) were shown to use North Inlet as a primary nursery. To examine potential differences in neonate shark abundance and growth between a developed estuary, Murrells Inlet, and a protected estuary, North …

Development Of Three Novel Edna Assays For Detecting Coastal Sharks, Kristina Dawn Flanigan

Electronic Theses and Dissertations

Environmental DNA (eDNA) analysis is an emerging, non-invasive community monitoring tool. This study aimed to determine if eDNA methods can be reliably used in a large brackish, partially mixed estuary by developing and testing three novel eDNA primers, for Sandbar Sharks (Carcharhinus plumbeus), Blacknose Sharks (Carcharhinus acronotus), and Bonnetheads (Sphyrna tiburo). These primers were designed to target 109, 156, and 120 base pair (bp) fragments, respectively, of the highly conserved NAD2 gene in the mitochondrial genome of each species. Primer function was validated through testing against 102 known genomic source samples and 25 filtered water samples from aquaria in which …

Use Of Space And Foraging Behavior Of Loggerhead Shrikes In Urban Areas, Katie Anne Maddox

Electronic Theses and Dissertations

Loggerhead shrikes, Lanius ludovicianus, are a declining grassland songbird native to North America. Land-use change has been associated with the decline of grassland bird species. However, the process of urbanization creates novel short-grass habitats reminiscent of shrikes’ natural habitats. Loggerhead shrikes have been observed living in developed areas, particularly in Southeastern coastal states. Understanding the long-term impacts of urban-dwelling on loggerhead shrike populations is vital to identifying whether urban areas offer refuge or act as an ecological sink for shrike populations.

In chapter one, I quantified the use of space by shrikes in urban habitats within Horry County, South …

Deterrent Effects Of The Select Magnetic And Repellent Treated (Smarttm) Hooks And The Recently Developed "Smarter" Hooks On Sharks In Recreational Hook-And-Line And Longline Trials, Ryan Lowndes

Electronic Theses and Dissertations

As bycatch continues to impact global shark populations, there is a continuing need for effective bycatch reduction devices. Prior research has shown promise in exploiting sharks' electrosensory ability to this end. We tested the deterrent efficacy of the Select Magnetic and Repellant Treated (SMARTTM) and the newly developed "SMARTER" hooks in experimental longline and hook-and-line trials. Both are magnetized and contain an electropositive metal component made of magnesium (SMART) and a magnesium alloy designed to extend longevity (SMARTER). We deployed 127 longlines with SMART hooks, SMARTER hooks, controls, and procedural controls from 2021-2022 in Winyah Bay, South Carolina, and caught …

Vibroacoustic Response Of The Tympanic Membrane To Hyoid-Borne Sound Generated During Echolocation In Bats, Chelsie Snipes

Electronic Theses and Dissertations

The hyoid apparatus in laryngeally echolocating bats forms a mechanical connection between the larynx and auditory bullae and has been hypothesized to transfer the outgoing echolocation call to the middle ear during echolocation call emission. We used µCT data to build models of the hyoid apparatus and middle ear from six species of bats and used finite element modeling (FEM) to measure the vibroacoustic response of the tympanic membrane due to hyoid-borne sound generated during echolocation. We found that hyoid-borne sound in all six species stimulated the eardrum within a range likely heard by bats. Although there were minor differences …

Neuronal Or Intestinal Knockdown Of C. Elegans Nadk-1 Decreases Oxygen Consumption And Reactive Oxygen Species, Jake Regan

Electronic Theses and Dissertations

Reactive oxygen species (ROS) such as H2O2 can damage cellular components and are formed as a byproduct of mitochondrial oxidative metabolism. Studies using the nematode C. elegans have found that increasing ROS during development or early adulthood can extend lifespan, while increasing ROS during later adulthood normally decreases lifespan. NADPH provides the reducing power for several cellular antioxidants and is synthesized in a two-step reaction from NAD+ with the first step being catalyzed by NAD kinase (NADK). In this study, the effects of knocking down C. elegans cytoplasmic NADK, nadk-1 globally or in a neuron or intestine-specific manner starting from …

Cyclic-Di-Gmp Regulates Salmonella Typhimurium Infection Of Epithelial Cells And Macrophages, Abdulafiz Musa

Electronic Theses and Dissertations

Regulation of the bacterial second messenger cyclic-di-GMP in Salmonella Typhimurium allows it to delicately alter phenotypes to optimize invasion and survive intracellularly in epithelial cells and macrophages to become virulent and cause infection. Cyclic-di-GMP concentration is regulated by the presence of external stimuli, sensory diguanylate cyclases (DGCs) and phosphodiesterases (PDEs), and cyclic-di-GMP binding effectors. Previous studies established that maintenance of low cyclic-di-GMP concentrations is required for survival in macrophages, and that deletion of 3 active PDEs reduces this survival. Here I showed that these 3 PDEs also influenced the infection of epithelial cells. Further studies re-established the decreased survival in …

Characterization Of Parp1-Dependent Poly-Adp-Ribosylation Of Sprtn, Quincee Simonson

Electronic Theses and Dissertations

DNA-protein crosslinks (DPCs) are a type of DNA lesion that form when proteins become covalently linked to DNA. It is estimated that replicating cells experience approximately 6,000 DPCs per day per genome during exponential growth (Ruggiano & Ramadan, 2021). If left unrepaired, DPCs can be lethal to cells. For this reason, cells have evolved multiple pathways to repair or bypass DPCs to survive. One such pathway involves SPRTN, a nuclear metalloprotease that plays a key role in the repair of DPCs through direct proteolysis (Lopez-Mosqueda et al., 2016; Vaz et al., 2016). Once SPRTN degrades the bulky protein component of …

Seroprevalence Of Sars-Cov-2 Antibodies Among Rural Healthcare Workers, Jordan Neises

Electronic Theses and Dissertations

The objective of this longitudinal cohort study was to determine the seroprevalence of antibodies to severe acute respiratory syndrome coronavirus-2 (SARSCoV- 2) in healthcare workers employed at healthcare clinics in three rural counties in eastern South Dakota and western Minnesota from May 13, 2020 through December 22, 2020. Three blood draws were performed at five clinical sites and tested for the presence of antibodies against the SARS-CoV-2 virus. Serum samples were tested for the presence of antibodies using a fluorescent microsphere immunoassay (FMIA), neutralization of SARS-CoV-2 Spike-pseudotyped particles (SARS-CoV-2pp) assay, and serum virus neutralization (SVN) assay. The seroprevalence was determined …

Application Of Crispr/Cas9 Whole Genome Screens To Advance Macrophage Biology, Kevin Wanniarachchi

Electronic Theses and Dissertations

Advances in CRISPR/Cas9 gene editing technologies present opportunities to better understand the contribution of individual genes to complex eukaryotic cellular processes. I have applied CRISPR whole genome screen technologies to inform further mechanistic understanding of macrophage fitness and neutral lipid metabolism. This work is important because macrophages play critical roles in immune function and are implicated as causative agents in disease states. Chapter One of this dissertation provides insights into how CRISPR genome screening technologies have improved biological discovery and key findings from their application and discusses how this technology can be implemented to advance the discovery of novel macrophage …

Understanding Human Gut Bacterial Interactions And Their Role In Colonization Resistance Against Clostridioides Difficile Using Mini-Bioreactor Array And Caenorhabditis Elegans As Model Systems, Achuthan Ambat

Electronic Theses and Dissertations

No abstract provided.

C3 And C4 Grass Dominated Plant Communities Differ In Response To Future Larger And Less Frequent Rainfall, Zigeng Chen

Electronic Theses and Dissertations

Climate change is leading to larger and less frequent rainfall in the Northern Great Plains (NGP). We ask if this change in rainfall would influence carbon (C) and nitrogen (N) cycling in the NGP. First, we collected soils from C3 and C4 grass dominated plant communities from western South Dakota and conducted an incubation experiment to explore the effects of soil water content (SWC) and temperature on soil respiration (Rs) and N mineralization rate (ΔIN). Second, we conducted a three-year rainfallmanipulation (RaMP) experiment with two distinct rainfall regimes (frequent/small and infrequent/large events with constant total monthly precipitation) and two grasses …

Fine-Scale Site Selection Of Strand-Feeding Common Bottlenose Dolphins (Tursiops Truncatus) And Their Prey, Deborah Kleinclaus

Electronic Theses and Dissertations

Strand-feeding is a unique, cooperative foraging strategy used by some common bottlenose dolphins (Tursiops truncatus) at low tide in South Carolina and Georgia salt marshes, where a group of dolphins charges schools of fish, thrusting them onto the bank with their bow wave and then capturing prey items onshore. Strand-feeding dolphins are estuarine residents and frequent predictable stranding sites, suggesting an intimate knowledge of the area. Dolphin behavior prior to stranding suggests they do not herd the fish before charging, but instead prey on fish already shoaling near the bank. The use of active acoustics from strand-feeders in order to …

Abundance And Growth Of Juvenile Atlantic Sturgeon In The Edisto River, Sc, Molly Katherine Takacs

Electronic Theses and Dissertations

Information on abundance and body growth are important for understanding the status and health of populations, and this information can be used to guide and monitor conservation and recovery efforts for species of conservation concern. The Atlantic Sturgeon (Acipenser oxyrinchus oxyrinchus) is an anadromous fish native to the Atlantic coast of the United States and Canada. Due to overfishing and habitat degradation, population levels declined, and Atlantic Sturgeon were placed on the Endangered Species list in 2012. Although there is substantial research on adult Atlantic Sturgeon, knowledge about their early life history is lacking. The objective of this study were …

Importance Of The Microhabitat And Microclimate Conditions In The Northern Gray-Cheeked Salamander (Plethodon Montanus) Across An Elevation Gradient, Trevor Chapman

Electronic Theses and Dissertations

The southern Appalachian Mountains have among the highest salamander diversity in the world, largely due to local speciation in the family Plethodontidae. Plethodontid salamanders (i.e., lungless salamanders) are particularly sensitive to habitat climate conditions due to their reliance on cutaneous respiration, and their immediate environmental conditions (microhabitat) likely influence their dispersion and activity more than the large-scale atmospheric conditions. The Northern Gray-cheeked salamander (Plethodon montanus) is restricted to high elevations in the Appalachian Mountains. Our goal was to investigate the relationship between P. montanus and its microhabitat by examining behavioral preference for climatic conditions, characterizing the microclimate with …

Alcohol, Stress, And Sex In The Bed Nucleus Of The Stria Terminalis, Nicholas Burski

Electronic Theses and Dissertations

Alcohol use disorder (AUD) costs the U.S. billions of dollars each year and is a leading cause of preventable death. AUD leads to many health complications, and those who suffer from AUD will often have stress and anxiety disorder comorbidities. To better understand this connection between AUD and stress and anxiety disorders, restraint stress (RS) and chronic-intermittent ethanol exposure (CIE) procedures were used on rats to analyze neuroinflammation via ELISA in the infralimbic and prelimbic cortices, and the bed nucleus of the stria terminalis (BNST). Levels of proinflammatory cytokines, TNF-α and IL-1β, were found to be elevated across different tests …

Characterization Of Microbotryum Lychnidis-Dioicae Secreted Effector Proteins That Manipulate Its Host Plant, Silene Latifolia., Ming-Chang Tsai

Electronic Theses and Dissertations

The smut fungal species Microbotryum lychnidis-dioicae is an obligate phytopathogen colonizing the plant host, Silene latifolia. A significant feature of M. lychnidis-dioicae infection is that the fungus can replace pollen on the anthers of susceptible host plants with fungal teliospores, thus earning the fungus the name: anther smut disease of flowers. The fungus synthesizes and secretes effector proteins into the cells of the plant host during infection, and the protein-protein interactions may interfere with and modify metabolism, plant development, and gene expression of the host to allow fungal colonization. Two potential fungal effector proteins, MVLG_06175 and MVLG_05122, were identified …

Quantifying Population-Level Effects Of Warm-Water Catch-And-Release Mortality On Muskellunge (Esox Masquinongy) In The James River, Virginia, Cory J. Bauerlien

Electronic Theses and Dissertations

Catch-and-release (C&R) has become a popular practice in many fisheries, both as a management strategy and as an angler ethic. The practice has been used to both increase the abundance and size structure of fish populations but relies heavily on the assumption that released fish survive the encounter. The Muskellunge (Esox masquinongy) is a large-bodied, coolwater predatory game fish that is highly prized by many anglers. Many Muskellunge fisheries have transitioned to almost exclusively C&R angling. Muskellunge fisheries have increased in both number and popularity, particularly in southern and mid-Atlantic rivers. However, there is little information on population characteristics for …

Winter Use Of Winyah Bay, Sc By The Spiny Dogfish (Squalus Acanthias), And Their Movements South Of Cape Hatteras, Nc, Meredith L. Langford

Electronic Theses and Dissertations

South of Cape Hatteras, NC, little is known about the coastal distribution and movement of the Spiny Dogfish, Squalus acanthias. Between January 2018 and March 2020 this study conducted winter demersal longline sampling in Winyah Bay, SC to investigate habitat use by Spiny Dogfish. In addition to monitoring Winyah Bay use through catch-and-release, 13 individuals were outfitted with implanted Vemco™ acoustic transmitters to monitor large scale movements along the U.S. East Coast. Across three sampling seasons 84 female Spiny Dogfish were captured within lower Winyah Bay. No males were observed over the course of the study. The mean fork length …

Evaluating Threats To The Water Quality Of Little Buffalo Creek And Sarver Run Through Water Quality Analysis And Backpack Electrofishing Surveys, Riley Williams

Electronic Theses and Dissertations

Currently, 64.8% and 52.2% of Little Buffalo Creek and Sarver Run stream kilometers are impaired, respectively. Impairment sources to Little Buffalo Creek include agriculture, riparian deforestation, on-site wastewater, and urban runoff. Impairment sources to Sarver Run are unknown. Our goal was to understand sources of impairment through water quality analysis and fish surveys. Water samples were collected monthly and analyzed for cation and anion concentrations. Mass ratio analysis comparing Br/SO₄ and Mg/Li, Ca/Mg and Ca/Sr, Mg/Na and SO₄/Cl, and SO_4/Cl and Mg/Li suggests that mine drainage and conventional oil and gas may be impacting water …