Life Sciences Commons^™

Deep Ocean Vehicle Applications And Modifications, Nichole "Nikki" T. Arm

Master's Theses

This project had two primary goals: (1) to explore opportunities to further a deep-ocean vehicle’s reach using alternative pressure spheres, and (2) to implement an existing deep-ocean vehicle (lander) in active scientific research.

I gained a greater understanding of the limitations and design choices made for existing pressure spheres using Finite Element Analysis (FEA). My simplified FEA model predicted sphere failure for the existing 30% Fiber Glass 70% Nylon injection molded spheres at an external pressure of 3,954psi or 2,690m ocean-depth (only a 7.38% error compared to the tested minimum failure depth), so I determined it a valid model. I …

Evaluation Of Facilitation On Translocation Outcomes For San Joaquin Antelope Squirrel In The Carrizo Plain, California, Patrick R. Anderson

Master's Theses

In arid and semi-arid environments, burrowing mammals play a key role in increasing landscape heterogeneity through facilitative species interactions. The loss of burrowing mammal populations can consequently lead to negative effects cascading through the ecosystem. It is critical to understand these facilitative interactions for conservation and management. Understanding facilitative interactions may improve wildlife management tools, like translocation, which is often not very successful. To investigate the importance of burrow facilitation on San Joaquin antelope squirrel (Ammospermophilus nelsoni; SJAS) translocation success, I designed a natural experiment with a burrowing facilitator, the giant kangaroo rat (Dipodomys ingens; GKR). I …

Placental Co-Culture Model Reveals Listeria Monocytogenes Utilization Of Monocytes For Vertical Transmission, Breanna Mackenzie Amelunke

Online Theses and Dissertations

Listeria monocytogenes is an opportunistic pathogen that can cross the protective placental barrier and infect the fetus, leading to congenital disabilities or death. Extracellular L. monocytogenes infection of the placenta has been well studied; however, the bacteria have not been observed translocating this barrier intracellularly. As an intracellular pathogen, L. monocytogenes could infect phagocytic cells that can be transported across the placental barrier. A novel cell co-culture system comprised of BeWo and HPVEC cell lines was established to model the human placental barrier. Barrier integrity was confirmed using immunostaining of tight junctions and a FITC-dextran permeability assay. The model was …

Non-Invasive Focused Ultrasound Treatment To Improve Depressive-Like Behavior In A Hemi-Parkinsonian Rat Model, Huda Rehman

ALL - Honors Theses

Parkinson’s disease (PD) is a neurodegenerative disorder in which there is a depletion of dopaminergic neurons in the substantia nigra pars compacta (SNc). Symptoms include those that are motor, such as tremors and rigidity, along with symptoms that are nonmotor, such as depression. Depression in Parkinson’s disease is seen in up to 50% of PD patients, and is often treated with traditional antidepressants, with varying levels of efficacy. In this research project, focused ultrasound was used as a non-pharmacological and non-invasive treatment to improve depressive-like behavior in a hemi-Parkinsonian rat model. To induce a hemi-Parkinsonian phenotype in rats, stereotaxic surgeries …

Repositioning Propranolol To Block Mitogenic Signaling In Breast Cancer, Alexa Noel Montoya

Open Access Theses & Dissertations

Breast cancer is the second most diagnosed cancer among women and is about 30% of all new cases of female cancers each year. It is projected that 1 in 8 every U.S. woman (about 13%) develop invasive breast cancer over the course of her lifetime. While advances in cancer research have made it possible to elucidate several breast cancer genomic subtypes, and develop new novel therapies, many of these agents are associated with significant toxicity, as well as high costs. A retrospective cross-sectional study of 404 breast cancer patients was performed to determine the effect of β-blocker usage on tumor …

Effect Of Macrophage Expressed Α7 Nicotinic Acetylcholine Receptor (Α7nachr) On Migration Of Macrophages During Inflammation, Kasey Keever

Electronic Theses and Dissertations

Sepsis is a life-threatening condition characterized by overwhelming inflammation, resulting in organ system damage, leading to a high mortality rate. Care in the clinical setting is supportive, and there are no approved sepsis-specific treatments. In septic mice, activation of the cholinergic anti-inflammatory pathway decreases cytokine secretion by leukocytes and improves survival. The cholinergic anti-inflammatory pathway is a reflex of the parasympathetic nervous system, converging on the α7 nicotinic acetylcholine (α7nAChR) at the surface of macrophages. Signaling through the receptor blocks NF-kB activation, thus cytokine secretion. Receptor activation has other effects on macrophages, including modulating their migration to …

The Impacts Of Maturation And Experience On Volumetric Neuroplasticity In Solitary And Social Bees, Mallory A. Hagadorn

All Graduate Theses and Dissertations, Fall 2023 to Present

Some animals are incredibly social, living and working together as one cohesive group. Alternatively, many animals are solitary, never living with and rarely interacting with others. A large body of biological research has focused on understanding the role that brains play in promoting these behavioral differences across species. Even so, it remains unclear why some brains facilitate social behavior while others do not. My dissertation aims to advance our understanding of this concept by characterizing bees’ brains and how they change over a lifetime. Bees are beneficial for investigating relationships between the brain and social behavior because some species are …

Geographic Variation In Blue Orchard Bee (Osmia Lignaria) Development And Performance As A Managed Pollinator In The Western United States, Morgan B. Scalici

All Graduate Theses and Dissertations, Fall 2023 to Present

Most flowering plants, including many cultivated food crops, will only produce well-developed fruits and seeds if pollen is transferred from one flower to another with the help of an animal pollinator. Honey bees are the most well-known and ubiquitous but are poor pollinators of some commercially important crops, or are in poor supply during crop bloom. In such cases, farmers will employ other managed pollinators such as bumble bees or solitary bees like mason and leafcutting bees. The blue orchard bee is North America's most agriculturally important native mason bee as effective pollinators of spring-blooming fruit crops. Differences in developmental …

Evolution And Natural Selection Of Olfactory Receptor Genes In Hawaiian Drosophila, Ngoc H. Ly

UNLV Theses, Dissertations, Professional Papers, and Capstones

The olfactory system is a powerful tool for sensing countless odorants. In Drosophila, the olfactory system is critical for detecting food, finding mates, laying eggs, avoiding predators, and adapting to new environments. Understanding the olfactory system in Drosophila will advance our knowledge of sensory biology in various insects and vertebrates, including humans. Drosophila has been a valuable model for biology since the early 1900s, and the Drosophila melanogaster olfactory system is well-studied. The Hawaiian Drosophila represent approximately 1/3 of the world’s Drosophila, however, there is limited research on Hawaiian Drosophila olfactory genes. We conducted a comparative analysis of …

Phenology Of The Invasive Balsam Woolly Adelgid, Adelges Piceae (Ratz.) (Hemiptera: Adelgidae), On Subalpine Fir In Northern Utah, Elizabeth L. Rideout

All Graduate Theses and Dissertations, Fall 2023 to Present

Balsam woolly adelgid (BWA) is an invasive true fir pest in North America. Native to Europe, BWA was first discovered in Utah attacking subalpine fir in 2017. Recent BWA-caused subalpine fir mortality in northern Utah has prompted the need for baseline biological research to support pest management. Small-bodied and blending easily with its environment, BWA is a challenging pest to detect and study. Phenology, or the timing and characteristics of life stages through the year, of BWA varies depending on elevation and climate and is unstudied in Utah. This research focuses on defining aspects of BWA’s phenology, including the number …

How Beavers (Castor Canadensis) Affect Habitat Availability For Two Native Oregon Turtles: Actinemys Marmorata And Chrysemys Picta Bellii, Rodé Krige

University Honors Theses

Oregon is home to two native freshwater turtle species: the northwestern pond turtle and the western painted turtle. Both turtles are Oregon conservation strategy species with a status rating of sensitive, indicating declining populations. Oregon’s decline in these turtle’s populations is thought to be predominantly due to loss and degradation of habitat that results from development and urbanization. Beavers’ ability to dam streams and create ponds may be creating habitat usable by turtles, but the relationship is under-studied. This study assessed water temperature, basking habitat, and overall turtle habitat suitability at beaver-dammed and control ponds in Portland, Oregon. Average basking …

Linking Microbial Community Assembly In Flowers With Function Under Diverse Environmental Conditions: A Case Study Involving Erwinia Amylovora, Christopher Skylar Mcdaniel

All Graduate Theses and Dissertations, Fall 2023 to Present

Fire blight, a devastating disease of pome fruit trees caused by the bacterium Erwinia amylovora, can cause millions of dollars in losses for producers each year around the globe. Management approaches that involve use of antibiotics, such as streptomycin, can be effective; although concerns exist over pollinator and crop health when using them regularly. Recently, there have been developments that allow for biological agents such as microbes to curtail fire blight infection. These agents work by competing with Erwinia for resources or space, producing antibacterial compounds, or even killing Erwinia cells on contact. Unfortunately, these agents do not yet …

The Mojave Poppy Bee (Perdita Meconis) And A Primary Plant Host, The Las Vegas Bear Poppy (Arctomecon Californica): Status And Interactions, Sarit Chanprame

All Graduate Theses and Dissertations, Fall 2023 to Present

The Mojave Desert is one of the most biodiverse places in North America. A harsh environment with many species results in complex relationships between animals and plants. This study focuses on one bee-plant relationship, the Mojave poppy bee, and the Las Vegas Bear Poppy.

The Mojave poppy bee is rare and has only been collected from Las Vegas Bear Poppy, Dwarf Bear Poppy, and a few species of prickly poppies. A 1995 report suggested the bee was a major contributor of pollination for the Las Vegas Bear Poppy in Clark County, Nevada. More recently (2019), their local extinction in southwestern …

Breaking Virulent: The Coincidental Evolution Of Virulence Factors In Bacteria., Rhiannon Emmanuelle Cecil

Electronic Theses and Dissertations

Understanding how innocuous organisms can evolve to be pathogenic to humans is of increasing global concern. Further, understanding how existing pathogens may evolved to be more virulent is also vital to our ability to provide healthcare to people afflicted with diseases that promote chronic bacterial infections, such as cystic fibrosis. With the rise of antibiotic resistance in both bacteria and fungi it is paramount that new therapeutics are identified. Understanding what mutations occur that result in increased virulence in microbes can potentially provide new targets for antimicrobial drugs to combat antibiotic resistance. The Coincidental Evolution Hypothesis is a fundamental hypothesis …

Phenological Activities Of Desert Bees Track Rainfall More Than Temperature And Predict Temporal Abundance Trends Over 16 Years, Jade Elijah Mclaughlin, Jade Mclaughlin

Biology ETDs

Phenology, the timing of recurrent biological events, is a key mechanism by which species adapt or acclimatize to variable environmental conditions, including those influenced by climate change. Measurable traits, including the onset and end of activity, peak activity, and duration, characterize the phenology of life events, and could be significant predictors of trends in population abundance or stability in a changing climate. Bees provide critical pollination services, and understanding the covariates of bee phenological traits can refine predictions on the vulnerabilities of bees and their services to climate change. We paired 16 years of monthly bee survey data (2002-2019) with …

Elucidating The Priming Mechanism Of Clpxp Protease By Single-Domain Response Regulator Cpdr In Caulobacter Crescentus, Kimberly E. Barker

Masters Theses

In Caulobacter crescentus, progression through the cell cycle is regulated by the AAA+ protease ClpXP, and there are several classes of cell-cycle substrates that require adaptors in order to be degraded. CpdR, a single domain-response regulator, binds the N-terminal domain of ClpXP and primes the protease for degradation of downstream factors (Lau et al., 2015). The ability of CpdR to bind ClpX is regulated by its phosphorylation state. In the unphosphorylated state, CpdR binds ClpXP and guides its localization to the cell pole during the swarmer to stalked transition, where CpdR is mediates degradation of substrates such as PdeA. …

Mimicking Biofilms: Photosynthetic Assessments Of C. Reinhardtii In 3 Physical Forms, John Michael Roesgen

Biology ETDs

Oxygenic photosynthesis supports the majority of life on Earth through the capture of energy from sunlight and the assimilation of CO₂ into basic building blocks of cells. Microalgae are fast growing and account for about half of global photosynthesis. In addition, they can be cultivated and their metabolism can be redirected to generate additional useful products ranging from biofuels to pharmaceuticals. However, the efficiency of metabolite production is severely impacted by the slow diffusion of CO₂ through water and the high energetic costs of harvesting microalgae from liquid cultures. Microalgae grow in open water, but they also form …

Characterizing Predator-Prey Relationships Of Great Lakes Fishes Using Targeted Stomach Content Dna Analyses, Matthew Richard Charron

Electronic Theses and Dissertations

Stomach content DNA (scDNA) analyses provide important insights into feeding ecology, trophic interactions, and diet composition of predator fishes. However, previous scDNA analyses have focused on investigating a small number of predator and prey fishes using binary presence/absence data. Here, I describe the development and validation of a panel of single-species quantitative real-time PCR (qRT-PCR) assays targeting the polymorphic mitochondrial cytochrome oxidase subunit 1 (CO1) region of 28 Great Lakes prey fishes. The assay panel will significantly increase the number of targeted prey species available for predator diet assessment, while at the same time improving detection sensitivity and through-put. I …

Targeting Bet Proteins Downregulates Mir-33a To Promote Synergy With Pim Inhibitors In Cmml, Christopher T. Letson

USF Tampa Graduate Theses and Dissertations

Chronic Myelomonocytic Leukemia (CMML) is a rare myeloid malignancy with a dismal prognosis and no therapeutic options which are capable of altering the natural course of the disease. There remains a significant need for novel therapies that are able to meaningfully improve patient outcomes. In this study we explore the effectiveness of Bromodomain and Extra-Terminal domain protein inhibitor (BETi) combinations in CMML. Preclinical studies in myeloid neoplasms have demonstrated efficacy of BETi. However, BETi demonstrate poor single agent activity in clinical trials. Several studies suggest that combinations with other anti-cancer inhibitors may enhance the efficacy of BETi. To nominate BETi …

The Impacts Of Embryo Development And Asynchronous Hatching On Morphology, Growth, And Development Of Larval Burbot (Lota Lota)., Andrew J. Shapiro

All NMU Master's Theses

Burbot (Lota lota) are native fish in Lake Superior and typically spawn during the winter under the ice or by migrating up rivers. The early life history of larval burbot, where they dispurse, how fast they develop, and what their survival rates have not been extensively studied. Asynchronous hatching is a strategy used by other cod species as a bet-hedging strategy to ensure that some larvae are hatched in more advantageous conditions in a varying environment. Asynchronous hatching has been documented in burbot, but the extent of the period and the impacts that asynchrony has on the development of …

Using Biometrics, Behavioral Observations, And Multiple Molecular Techniques To Assess The Impacts Of Changes In Temperature And Salinity On The Common Bay Mussel (Mytilus Trossulus), Casey Martin

Dissertations and Theses

The intertidal zone is a place of rapid and frequent change that is home to a variety of creatures who are essential to the integrity of the habitat. Mussels are robust sessile bivalves that anchor to the rocks of the intertidal. The prominent species on the Oregon Coast, the Common Bay Mussel (Mytilus trossulus), plays an essential role as a coastal food source, water column filter, and barrier to prevent erosion due to wave action. Mytilus trossulus withstands daily shifts in temperature, salinity, and tide, as well as seasonal changes. Global climate change due to excess carbon emissions …

Effects Of A Major Hurricane On Dynamics, Structure, And Composition Of Mississippi River Delta Forests, Lance C. Umlang

LSU Doctoral Dissertations

Tropical cyclones recurrently influence coastal forests worldwide. Tree survival (resistance) and post-cyclone recruitment (resilience) can vary with cyclone intensity, producing differences in composition, arboreal structure, and dynamics among affected forests. Studies of tropical cyclone wind effects on coastal forests typically emphasize damage more than post-cyclone responses. We hypothesized that intense cyclones might produce large, stratum-dependent effects that prevent affected forests from returning to pre-storm conditions. We explored direct effects of major Hurricane Katrina and post-hurricane changes in oak-dominated bottomland and cypress/tupelo-dominated swamp forests within the inactive portion of the Mississippi River deltaic plain. Overall mortality was high (14-25%) but concentrated …

Patterns In Biodiversity And Community Assemblage In Macrofaunal Fouling Communities On Tampa Bay Floating Docks, Cassidy C. Bell

USF Tampa Graduate Theses and Dissertations

Understanding biodiversity trends of highly disturbed urban landscapes is essential as anthropogenic factors continue to drive global biodiversity loss. Within marine ecosystems, macrofaunal fouling communities, aggregations of epibenthic invertebrates that colonize human-made structures, represent an ecologically important subset of urban coastlines. Tampa Bay is a highly urbanized estuary in Florida, USA, and is home to the state’s largest port, Port Tampa Bay. This makes the bay a prime site for the introduction of new species, with many organisms either considered invasive or cryptogenic, their origins left unclear. Many factors may contribute to the communities that form on urban structures including …

Hurricanes And Tropical Storms’ Impact On Water Quality In Lake Okeechobee, Florida, Daniela Vasquez Diaz

USF Tampa Graduate Theses and Dissertations

Hurricanes are natural events with catastrophic outcomes, while climate change's effects on their intensity and frequency remain discussed. However, it is crucial to analyze these through models and statistics to understand their behavior and impact on the basins. Particularly in lakes on tropical coasts since disruptive events such as hurricanes tend to be highly affected. Lake Okeechobee is a unique lake located in Florida and one of the largest freshwater lakes. The lake and some of its significant stations are the locations chosen to perform the investigation. The main focus of the investigation is determining the effect that hurricanes have …

Distinct Nrf2 Signaling Thresholds Mediate Lung Tumor Initiation And Progression, Janine M. Deblasi

USF Tampa Graduate Theses and Dissertations

NRF2 is a redox-responsive transcription factor the directs the antioxidant program and several critical metabolic processes. Mutations in NRF2 or its negative regulator KEAP1 occur in up to one third of non-small cell lung cancers (NSCLCs) and are often associated with resistance to therapy and poor outcomes. In the present studies, murine alleles of the Keap1 and Nrf2 mutations found in human NSCLC were developed and I comprehensively investigated their impact on tumor initiation and progression. I observed that chronic Nrf2 stabilization by Keap1 loss-of-function or Nrf2 activating mutation was not sufficient to cause lung tumor initiation, even when p53 …

Short-Term Versus Long-Term Effects Of Nitrogen Addition And Warming On Ecosystem N Dynamics In A Grass-Dominated Temperate Old Field, Benjamin F. A. Souriol

Electronic Thesis and Dissertation Repository

Increased atmospheric nitrogen (N) deposition and climate warming are both anticipated to influence the ecosystem N dynamics of northern temperate ecosystems substantially over the next century. Nevertheless, in field experiments with N addition and warming treatments, temporal scale can play an important role in determining the extent of treatment effects on N dynamics, and it is unclear to what extent the results of short-term studies can be extrapolated to responses over longer time scales. I compared the short-term versus long-term effects of N addition and warming on net N mineralization, N leaching, and N retention in a grass-dominated old field. …

Physiological And Behavioural Responses Of Arctic-Breeding Shorebirds To Weather And Habitat Conditions, Sara Bellefontaine

Electronic Theses and Dissertations

Arctic-breeding shorebirds balance proximate and ultimate trade-offs in an energetically demanding environment. While these species are selective of nest sites, previous research shows that the characteristics of preferred shorebird nests do not predict increased breeding success. Thus, I aimed to identify detectable mechanisms driving nest preferences in Arctic-breeding shorebirds. Using an archival dataset, I first examined long-term nest preferences in relation to wind conditions at the East Bay Migratory Bird Sanctuary, on Southampton Island, Nunavut, Canada. I then studied energetic responses of two shorebird species to weather conditions across various nest types in a field study using non-invasive heart rate …

Determining The Structure And Function Of A Bacteriophage Called Leozinho, Leonardo Rodrigues Venturotti

Biology Student Work

A research team, having discovered a bacteriophage named Leozinho a couple of years ago, embarked on a mission to unravel the structure of an unidentified gene, gp_61. They utilized ESMatlas, Foldseek, and ChimeraX to predict the structure of gp_61 and afterwards various laboratory procedures were employed to facilitate the growth of the gene. Ultimately, the experiment was concluded with the successful cloning of gp_61 into a plasmid vector for protein expression.

Characterizing Allosteric Regulation And Conformational Dynamics In Staphylococcus Aureus Pyruvate Carboxylase, Amanda Joan Laseke

Dissertations (1934 -)

Pyruvate carboxylase (PC) produces oxaloacetate from pyruvate and bicarbonatein an ATP-dependent manner. The catalytic activity of PC places it at a pivotal intersection between catabolism and anabolism. Understanding the essential metabolic role of PC requires a more complete description of how its activity is regulated and how that regulation is manifested through changes in conformational dynamics. PC activity is regulated by the mutually exclusive binding of the allosteric activator, acetyl-CoA, and the allosteric inhibitor, L-aspartate. The binding site for acetyl- CoA has largely been identified, but the binding location for the acetyl moiety is unknown. Given that the acetyl moiety …

Dephosphorylation Of Mpk6 And Mpk3 By Phosphatases Modulates Responses To Herbivory In Arabidopsis, Claire Teresa Hann

Theses and Dissertations

As sessile organisms, plants rely on extracellular signals and chemical responses to defend against stressors. Extracellular stress signals inducing defense responses originate both from biotic or abiotic threats, and from products of tissue damage or hormones. In defense against herbivores, essential responses include rapid generation of jasmonic acid (JA) at the wound site, followed by the global expression of genes that impede digestion and growth. Early defense gene expression amplifies JA production, while later JA-responsive gene expression causes the accumulation of defense products. MAP kinase (MAPK) pathways play a central role in mediating the perception of self, non-self, and hormonal …