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Acute pH sensitivity of many neural mechanisms highlights the vulnerability of neurotransmission to the pH of the extracellular milieu. The dogma is that the synaptic cleft will acidify upon neurotransmission because the synaptic vesicles corelease neurotransmitters and protons to the cleft, and the direct data from sensory ribbon-type synapses support the acidification of the cleft. However, ribbon synapses have a much higher release probability than conventional synapses, and it’s not established whether conventional synapses acidify as well. To test the acidification of the cleft in the conventional synapse, we used genetically encoded fluorescent pH reporters targeted to the synaptic cleft of Drosophila larvae. We observed alkalinization rather than acidification during activity, and this alkalinization was dependent on the exchange of protons for calcium at the postsynaptic membrane. A reaction-diffusion computational model of the pH dynamics at the Drosophila larval neuromuscular junction was developed to leverage the experimental data. The model incorporates the release of glutamate, ATP, and protons from synaptic vesicles into the cleft, PMCA activity, bicarbonate, and phosphate buffering systems. By means of numerical simulations, we reveal a highly dynamic pH landscape within the synaptic cleft, harboring deep but exceedingly rapid acid transients that give way to a prolonged period of alkalinization., 2023, Includes bibliography., Degree granted: Dissertation (PhD)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

Learning to effectively execute goal-directed tasks generally requires guidance from knowledgeable experts that can direct the performer’s attention toward important environmental features. However, specifying the optimal attentional strategies is difficult due to the subjective nature of perceptions and the complexity of the underlying neural processes. The current skill acquisition literature emphasizes action-based contingencies through Predictive and Ecological models when examining attentional processes, while Perceptual Control Theory advocates for perceptual-based mechanisms. To evaluate the efficacy of these models, this study implicitly primed one hundred fifteen participants to focus on action-based or perceptual-based aspects during an interceptive task. It was predicted that the perceptual-based priming condition would result in faster learning and greater resilience to environmental disturbances. However, the highly variable results did not show significant differences in learning rate or resilience between the action and perceptual-based conditions. Ultimately, the variability in the findings suggests that a superior performance depends on numerous factors unique to each performer. Consequently, instructional methods cannot rely on a single optimal attentional strategy for gathering environmental information. Instead, the dynamic interplay between the individual and the environment must be considered to foster the skill development of novice performers., 2023, Includes bibliography., Degree granted: Thesis (MA)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

Previously published in Geographies 2023, 3(1), 161-177 (DOI: https://doi.org/10.3390/geographies3010010) Inundation dynamics coupled with seasonal information is critical to study the wetland environment. Analyses based on remotely sensed data are the most effective means to monitor and investigate wetland inundation dynamics. For the first time, this study deployed an automated thresholding method to quantify and compare the annual inundation characteristics in dry and wet seasons in the Everglades, using Landsat imagery in Google Earth Engine (GEE). This research presents the long-term time series maps from 2002 to 2021, with a comprehensive spatiotemporal depiction of inundation. In this paper, we bridged the research gap of space-time analysis for multi-season inundation dynamics, which is urgently needed for the Everglades wetland. Within a GIS-based framework, we integrated statistical models, such as Mann–Kendall and Sen’s Slope tests, to track the evolutionary trend of seasonal inundation dynamics. The spatiotemporal analyses highlight the significant differences in wet and dry seasons through time and space. The stationary or permanent inundation is more likely to be distributed along the coastal regions (Gulf of Mexico and Florida Bay) of the Everglades, presenting a warning regarding their vulnerability to sea level rise., 2023, Includes bibliography., Degree granted: Thesis (MS)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

Coastal wetlands across the Indian River Lagoon (IRL) on the east coast of Florida have been impounded for mosquito control purposes, which have been known to have adverse effects on overall fish populations. The objective of this project was to assess the use of culverts by species of larval fish at three impounded mangrove sites in the IRL. Light traps were used to collect samples of larval fish (both inside the basins and in the surrounding lagoon) which were humanely euthanized, preserved, and examined under a digital microscope. A total of 3,926 fish were collected from 24 taxa in 576 samples over the year-long study. Larval seasonality generally followed known reproductive seasonality of the species captured. Inside the impoundments were dominated by species known to spawn in and around mangroves such as the Gambusia holbrooki and Poecilia latipinna. Species that spawn in the IRL or in coastal waters that subsequently use the IRL as a nursery (such as Anchoa mitchilli and Gobiosoma robustum) had relatively low catches in the impoundments. Larvae of the main sportfishery species that have juveniles known to utilize the studied impoundments (Megalops atlanticus, the Atlantic tarpon, and Centropomus undecimalis, the common snook), were rarely caught inside the impoundments or in the surrounding IRL. The low numbers of IRL and offshore spawning larvae that enter the impoundments may be hindered by restricted water flow through culverts connecting the habitats, or by their inability to survive the low DO conditions often found inside the impoundments, especially during the summer. The lack of larval tarpon and snook in the light collections suggest that these species metamorphose from the larval to juvenile stage outside of the impoundments, before they enter the mangrove-dominated nursery habitats. The results of the study can be used to further modify impoundment restoration and management strategies to enhance their role as fish nursery habitats., 2023, Includes bibliography., Degree granted: Thesis (MS)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

Prior research on neurophysiology of infants of depressed mothers commonly has focused on EEG power and asymmetry. Whether infants of depressed mothers show differences in coherence is undetermined. This study examined the development of EEG alpha coherence in infants of mothers with various degrees of depression. Also investigated was the normative development of alpha coherence in infancy. The relationship between maternal depression and infant coherence was analyzed at different infant ages, from 1-12-months-old. There were significant effects of maternal depression on infant coherence between frontal-occipital regions, frontal-parietal regions, and central-parietal regions, in 1-month-olds. There were also significant maternal depression effects in central-parietal coherence in 1-3-month-olds and 3-6-month-olds. Differences were in the right hemisphere and were generally characterized by lower coherence in infants whose mothers had higher depression. Infants whose mothers had lower depression demonstrated age-related decreases in coherence, but infants of more highly depressed mothers did not show age-related differences., 2023, Includes bibliography., Degree granted: Thesis (MA)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

Climate change has intensified thermal anomalies in coral reef ecosystems, contributing to coral bleaching and decline. As corals die, reef fragmentation increases, and species interactions in the benthos change. However, it is unclear which competitive interactions may prevail and structure future reef ecosystems. The aim of this thesis was to evaluate the effect of thermal anomalies on coral reef benthic competitive interactions. Photoquadrats in southeast Florida reef sites were assessed over 15-years to generate interaction metrics and determine effects on hard coral survivorship. A state-transition model was created to predict the resultant community across 100 years with thermal scenarios concordant with the IPCC RCP 4.5 and 8.5. Interaction doubled across three thermal anomaly events and ended up mainly composed of pairwise examples between Dictyota, Halimeda, Niphates erecta, and Erythropodium caribaeorum. Century projections confirm that soft coral and sponge interactions will increase through thermal anomalies. The survival of hard corals was more successful when colonies were in permanent or intermittent interactions than when colonies were solitary (indirect interactions). Living hard corals were mostly found interacting with the macroalgae, Dictyota, and sponge Aplysina cauliformis, while corals that died were mainly in interactions with the soft coral E. caribaeorum, and sponges N. erecta, C. delitrix, D. anchorata, and Ircinia campana. Future reefs will be composed of more interactions between soft corals and sponges as thermal anomalies intensify, which will result in a patchier and flatter community., 2023, Includes bibliography., Degree granted: Thesis (MS)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

In this dissertation, we develop analogues to various notion in rigidity theory in the case of angular constraints. Initially, we were interested in angle dependencies. However, by defining a chromatic graph determined by the point-line incidence or angle graph of a given angularity, we were able to determine an assortment of properties. We provide a conjectured angular rigidity matroid involving count matroids, tranversal matroids, and traditional rigidity matroids. We consider realizations of chromatic graphs in R2 as well as C similar to the work in [3]. We extend the notions of pure conditions and infinitesimal motions using the chromatic rigidity matrix by applying techniques from algebra geometric as well as classical geometric results, such as Thales’ theorem. Some realizations I computed inspired curiosity in the space of realizations of angle-constrained graphs. We generate uniformly random sets of angle constraints to consider the space of realizations given these angle sets. We provide some results for the maximum number of possible realizations for some chromatic graphs on four vertices. We conclude with some directions for further research to develop our notions of angle-rigid graphs and their properties., 2023, Includes bibliography., Degree granted: Dissertation (PhD)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

Much of Interior Alaska contains permafrost, which is a permanently frozen layer found within or at the surface of the Earth. Historically, this permafrost has experienced relative stability, with limited thaw during warmer summer months and fire events. However, largely due to the impact of a warming climate, among other factors, permafrost that would typically experience limited thawing during the summer season has recently been thawing at an unprecedented rate. Trapped by this layer of permafrost is a large quantity of carbon (C), which could be released into the atmosphere as greenhouse gases such as carbon dioxide (CO2) and methane (CH4). Due to the remoteness of the Arctic, there is a lack of yearly recorded permafrost thaw depth and snow depth values across much of the region. As such, the focus of this research was to establish a framework to identify how permafrost thaw depth and snow depth can be predicted across both a 1 km2 local scale and a 100 km2 regional scale in Interior Alaska by a combination of 1 m2 field data, airborne and spaceborne remote sensing products, and object-based machine learning techniques from 2014 – 2022. Machine learning techniques Random Forest, Support Vector Machine, k-Nearest Neighbor, Multiple Linear Regression, and Ensemble Analysis were applied to predict the permafrost thaw depth and snow depth. Results indicated that this methodology was able to successfully upscale both the 1 m2 field permafrost thaw depth and snow depth data to a 1 km2 local scale before successfully further upscaling the estimated results to a 100 km2 regional scale, while also linking the estimated values with ecotypes. The best results were produced by Ensemble Analysis, which tended to have the highest Pearson’s Correlation Coefficient, alongside the lowest Mean Absolute Error and Root Mean Square Error. Both Random Forest and k-Nearest Neighbor also provided encouraging results. The presence or absence of a thick canopy cover was strongly connecte, 2023, Includes bibliography., Degree granted: Dissertation (PhD)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

Intensity modulated proton beam scanning therapy allows for highly conformal dose distribution and better sparing of organ-at-risk compared to conventional photon radiotherapy, thanks to the characteristic dose deposition at depth, the Bragg Peak (BP), of protons as a function of depth and energy. However, proton range uncertainties lead to extended clinical margins, at the expense of treatment quality. Prompt Gamma (PG) rays emitted during non- elastic interactions of proton with the matter have been proposed for in-vivo proton range tracking. Nevertheless, poor PG statistics downgrade the potential of the clinical implementation of the proposed techniques. We study the insertion of the nonradioactive elements 19F, 17O, 127I in a tumor area to enhance the PG production of 4.44 MeV (P1) and 6.15 MeV (P2) PG rays emitted during proton irradiation, both correlated with the distal fall-off of the BP. We developed a novel Monte Carlo (MC) model using the TOPAS MC package. With this model, we simulated incident proton beams with energies of 75 MeV, 100 MeV and 200 MeV in co-centric cylindrical phantoms. The outer cylinder (scorer) was filled with water and the inner cylinder (simulating a tumor region inside water-equivalent body) was filled with water containing 0.1%–20% weight fractions of each of the tested elements., 2023, Includes bibliography., Degree granted: Dissertation (PhD)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

Octopus predation and species selection contribute to community structure in benthic habitats, where plastic pollution accumulates. This study investigated how the bioactive plastic additive oleamide alters trophic interactions and behaviors of the common octopus (Octopus vulgaris) and its prey. We quantified activity budgets and trophic interactions for octopuses and multiple prey types (hermit crabs, free-living crabs, bivalves, and gastropods) before and after exposure to oleamide. Our analysis suggested that some taxa (octopuses and hermit crabs) exhibit more active behaviors during oleamide exposure. Free living crabs responded primarily to the threat of octopus predation, while other taxa did not show clear behavioral responses. Exposure to oleamide increased trophic interactions and the probability of mobile prey taxa being observed on the same side of the aquarium as the octopus, thus increasing the opportunity for predation. Our results support previous research showing that plastic leachates can impair decision-making, making prey more susceptible to predation., 2023, Includes bibliography., Degree granted: Thesis (MS)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

The Winston-Lutz has been the standard test for isocenter convergence, however, any adjustments needed – in case the test fails – are time consuming since the source of error is not readily available from the results. Isopoint by the Aktina Medical company has been developed to address this problem via decoupling the mechanical from the radiation isocenter and providing the user with information that was inaccessible before. The focus of this research is to perform optimization of the isocenter by using the Isopoint and to confirm the validity of its results, as well as to find how much time is saved via this new technology. The data for this project was collected on a 2012 Elekta Synergy, a Varian 21ix, and a 2021 Elekta Versa through partnership with GenesisCare. Our findings indicate that the Isopoint will allow for more accurate and speedy adjustments of the LINAC (Linear Accelerator) and will be integral in the future of this field., 2023, Includes bibliography., Degree granted: Thesis (PSM)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

While the thalamus and hippocampus are generally understood to contribute to mammalian spatial navigation, the degree to which thalamic input contributes to representations of space during navigation remains unclear. Specifically, anterior dorsal thalamic nuclei (ADN) provide a relational or directional framework known as the head direction (HD) network, which is hypothesized to play a significant role in guiding hippocampal-dependent navigation. The current study focuses on the contribution of the ADN to direction and place-dependent spatial navigation in adult male C57BL6J mice. An inhibitory chemogenetic (hM4Di) receptor was bilaterally expressed in the ADN after viral stereotaxic injection. Mice were trained in a spatially focused task, the Morris water maze (MWM), and after systemic administration of the hM4Di agonist, clozapine-Noxide (CNO) at 5mg/kg, demonstrated equivalent preference for using directional or place-based search behavior. These results suggest that the selective silencing of ADN at 5mg/kg CNO does not negatively affect spatial navigation in mice., 2023, Includes bibliography., Degree granted: Thesis (MA)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

The goal of this study is to determine how negative information affects purchasing decisions and what neurological processes are included in these purchasing decisions. Specifically, this study aims to explore the effect of consumers receiving the same negative attribute twice versus two different negative attributes for a product. The introduction of this study will discuss background concepts like the Controlled Semantic Cognition Framework from Lambon Ralph et al., (2017) and the neural processes behind selection as discussed in Thompson-Schill et al., (1997). The results indicated that there were differences in hemodynamic response between conditions where the same negative attribute was presented with a product twice versus conditions where two different negative attributes were presented with a product. Both behaviorally and hemodynamically, the results provide evidence supporting an inner conflict when dealing with two negative alternative choices. Future research could include realistic advertisements to better mimic everyday scenarios., 2023, Includes bibliography., Degree granted: Thesis (MA)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

The mechanisms of larval fish transport have been rigorously studied in the past several decades, building foundational knowledge of key biological and environmental factors with which to inform decisions about species management. This study has been built upon information gained from previous studies to further elucidate the processes involved at the recruitment stage of larval fishes. Vertical swimming behaviors of larval fishes enable deliberate orientation within the water column to allow organisms of limited mobility greater control over their horizontal movements. Vertical accumulation patterns of larvae are found to be tightly dependent on the strength of stratification within the water column at nursery entrances, such as estuaries. Onshore currents, such as upwelling and surface intrusions, are found to be conduits for entry into these systems. This study observed and analyzed the influence of intrusions by the Gulf Stream into the Fort Pierce Inlet and the vertical accumulation patterns of late-stage larvae associated with those events. This study incorporated a well-established zooplanktonic abundance sampling technique to achieve two primary goals: (1) to analyze the vertical abundances of larval fishes in stratified flow during Gulf Stream intrusions and (2) to assess the correlation between larval influx and intrusion events. The results of this study show a significant and positive correlation between propagule pressure of larval fishes and incidence of Gulf Stream intrusion events. Whereas previous studies have primarily described the spatiotemporal aspects of larval transport in a broader sense, our findings revealed a greater layer of complexity in the mechanisms of transport by incorporating localized hydrographic features. The information gleaned from these results can inform the ecological considerations of future fisheries management and study efforts via additional understanding about the role of physical oceanographic events in a critical lif, 2023, Includes bibliography., Degree granted: Thesis (MS)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

The term "collapse" has become a widely used term that oversimplifies the intricate histories of human-environment interactions. It has contributed to the belief that civilizations in the Americas and the tropics could not endure over time. However, the Manteño civilization of the Ecuadorian coast challenges this notion. Flourishing for a thousand years (ca. 650–1700 CE), the Manteños inhabited the neotropics at the gates of one of the world's most influential climatic forces, the El Niño-Southern Oscillation (ENSO). To thrive, the Manteños needed to navigate the extremes of ENSO during the Medieval Climate Anomaly (MCA, ca. 950–1250 CE) and the Little Ice Age (LIA, ca. 1400–1700 CE) while capitalizing on ENSO's milder phases. This research uses change detection analysis of Normalized Difference Vegetation Index (NDVI) on Landsat satellite imagery under various ENSO conditions from 1986 to 2020 in southern Manabí, where the 16th-century Manteño territory of Salangome was situated. The findings indicate that the cloud forests found in the highest elevations of the Chongón-Colonche Mountains provide the most resilient environment in the region to adapt to a changing climate. Further investigations of the cloud forest of the Bola de Oro Mountain using Uncrewed Aerial Vehicles (UAV) equipped with LiDAR, ground-truthing, and excavation uncovered a landscape shaped by the Manteños., 2023, Includes bibliography., Degree granted: Dissertation (PhD)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

Endometriosis is an inflammatory disease that affects one in ten women, where ectopic endometrial cells grow outside of the uterus. Lesions are estrogen dependent but progesterone resistant due to decreased progesterone receptor activity. This study investigated whether a combination of dienogest, a synthetic progesterone, and calcitriol, vitamin D’s active form, had an additive or synergistic effect in the therapy of endometriosis. Experiments were conducted on immortalized endometriotic epithelial (12Z) and stromal (22B) cell lines. Results revealed that the combination therapy effectively inhibited cell viability in spheroids, limited proliferation, and reduced cell migration in cell monolayers of lipopolysaccharide- induced cells. Concentrations of prostaglandin E2, a key inflammatory cytokine, were measured from the supernatants of 12Z cells. The combination did not alter CD44 and progesterone receptor levels on the surface of 12Z cells. Further testing in a mouse model is necessary to determine the efficacy of the combination in vivo., 2023, Includes bibliography., Degree granted: Thesis (MS)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

Animals display a remarkable variety of social behaviors that are necessary for survival. Despite the importance of social behaviors, the neurobiological mechanisms underlying the evolution of such behaviors are largely unknown. The Mexican tetra, Astyanax mexicanus, is a powerful model for studying how behaviors evolve, including social behavior. A. mexicanus exists as a schooling surface form and a non-schooling cave form. Here we have utilized this model in order to investigate how differences in the behavior of individuals result in differences at the level of emergent group social behaviors. We begin by reviewing how fish have contributed to the study of social behavior in Chapter 1, then continue to dissect differences in the schooling and shoaling behavior of adult surface and cave fish in Chapter 2, and finally address ontogenic differences that result in these differences in Chapter 3. All-in-all this, work reveals how evolution may act on the behavior of individuals to produce differences in relevant group behaviors., 2023, Includes bibliography., Degree granted: Dissertation (PhD)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

By regulating the abundance of prey populations, predators can directly and indirectly influence food web interactions in ways that influence ecosystem function. Predator functional responses quantify how predator foraging rate changes with prey abundance. Due to the large numbers of individuals needed for these experiments, most studies are conducted on small, abundant taxa. Consequently, we know relatively little about the functional responses of many marine taxa, especially those that are large and highly mobile. We present a novel method for studying predator foraging behaviors by integrating two innovative approaches: passive acoustics to document the occurrence of underwater predation events in concert with a recently developed statistical method that uses the times between predation events to estimate functional response parameters. We demonstrate and expand on the application of these methods by quantifying the shape of the predator functional responses for whitespotted eagle rays (Aetobatus narinari) preying on hard clams (Mercenaria mercenaria)., 2023, Includes bibliography., Degree granted: Thesis (MS)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

The goal of this study is to explore a novel concept of justice using allocations of outcomes and understanding the connection between those allocations and social cognitive variables. Justice is conceptualized through the lens of two opposing frames: consistency and compensatory. Participants assigned positive or negative outcomes to one of two hypothetical people, one person being depicted as “lucky”, the other as “unlucky.” A consistency sense of justice views justice as keeping the order of the world (positive with lucky), whereas a compensatory sense of justice understands it as a balancing act (positive with unlucky). ANOVA’s were ran and a single significant difference was found. In one condition, those whose had a consistency sense of justice had a significantly more internal locus of control than those who had a compensatory sense of justice. Further research will be needed to clarify why this difference did not emerge for all allocations., 2023, Includes bibliography., Degree granted: Thesis (MA)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

Infants have an innate desire to form social bonds and jealousy protests are an attempt to regain exclusive maternal attention from a social usurper. The current study examined neurophysiological and bio-hormonal processes related to jealousy responses during the first year and a half of life. Prior to and after the first year of life, infants express jealousy protest behavior when faced with a social threat. Resting-state frontal EEG coherence indicated a developmental shift from bilateral connectivity in younger infants to increased frontal specialization in older infants in relation to jealousy responses. Furthermore, 6- to 9-month-old infants exhibited more frontal neuroconnectivity in the right hemisphere (i.e., an area related to negative emotions) of the brain compared to left when faced with social threat. Lastly, social threat activated HPA reactivity in infants higher in temperamental distress. This study provides further evidence for the emerging links between physiological and socioemotional responses in infancy due to loss of exclusive maternal attention., 2023, Includes bibliography., Degree granted: Dissertation (PhD)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

Prostate cancer, the most frequent non-skin cancer, is the second leading cause of cancer-related deaths in males within the United States. Men diagnosed with metastatic prostate cancer have a 5-year survival rate of approximately 30%. Goals of this study were to produce a combination of compounds that are effective against the disease with minimal side effects on normal cells, especially those of the immune system. This study showed KBU2046 in combination with calcitriol, limit proliferation, inhibit migration, and are cytotoxic in a testosterone dependent human prostate cancer cell line. Organic compounds, ellagic acid and curcumin were tested alone and in combination with either calcitriol or KBU2046. No combinations were as effective as KBU2046 and calcitriol in inhibiting migration and proliferation of LNCaP cells. The findings of this study support further investigation into therapeutic use of a combination of KBU2046 and calcitriol in prevention and remission of human prostate cancer., 2023, Includes bibliography., Degree granted: Thesis (MS)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

The study of the electrical properties of red blood cells (RBCs) plays a crucial role in advancing our understanding of human health. As RBCs age, they undergo changes that affect hemorheology and blood microcirculation, which have far-reaching implications for disease research. Furthermore, the shortage of RBC storage units can be a major issue for patients, underscoring the importance of characterizing RBC aging with respect to cell densities. In individuals with abnormal hemoglobin disease, alterations in hemoglobin and its functionality can modify the volume and density of RBCs, making their study even more crucial. To this end, our aim is to investigate the impedance alterations of RBCs after distributing them into different layers based on their densities. We have developed a novel method for non-invasive, rapid, and real-time single-cell analysis of RBCs. Our approach involves the use of electrical impedance spectroscopy (EIS) to study the cells after performing cell fractionation. Our studies indicate an increasing trend for RBC resistance and a decreasing trend for the cell membrane as the density of the layer increases. Additionally, we have developed a method for extracting hemoglobin with high purity from fresh samples of RBCs. By passing lysed RBCs through ultrafiltration devices and removing debris and membranes, we were able to isolate hemoglobin. Using the EIS technique, we studied the alterations of impedance over a frequency range, obtaining valuable insight into the electrical properties of hemoglobin., 2023, Includes bibliography., Degree granted: Dissertation (PhD)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

High nest incubation temperatures can result in numerous physiological and behavioral outcomes in sea turtle hatchlings, including body characteristics for efficient swimming. This project examined the effects of incubation temperature on yolk metabolization, body morphology, buoyancy, swimming kinematics, and blood chemistry to better understand variations in locomotor performance in loggerhead (Caretta caretta) sea turtle hatchlings of South Florida. Nest temperatures, body measurements, and blood samples were collected in conjunction with swim-trial force measurements and video recordings. Data suggest hatchlings from nests with higher incubation temperatures tend to be significantly smaller in size, less buoyant, and display lower power stroke frequencies. These variations between hatchling morphology and performance indicate hatchlings from high temperature nests (i.e., >33°C) may exhibit weaker swimming abilities. The results of this study provide a further understanding of the effect of incubation temperatures on hatchling physiology and early survival in their important frenzy period., 2023, Includes bibliography., Degree granted: Thesis (MS)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

Core-Collapse Supernovae (CCSNe) are some of the most powerful events in the universe liberating an astonishing 3×1053 ergs of the gravitational binding energy released by the collapse of the stellar core to a nascent neutron star (PNS) that is formed in these events. The visible display is capable of outshining the entire galaxy where it inhabits. Most of this energy, ~ 99%, is carried away by neutrinos of all flavors, however. According to the favored theory of CCSNe, the production and transport of neutrinos from the dense core through the less dense mantle is believed to deposit energy in the mantle and thereby initiate the supernova explosion. Numerically modeling these events realistically to validate the model therefore requires an accurate neutrino transport algorithm coupled to sophisticated neutrino microphysics to compute the emission, transport, and energy deposition of neutrinos. The CHIMERA code is a radiation-hydrodynamics code that has been developed to numerically model CCSNe in multiple spatial dimensions. The neutrino transport algorithm currently incorporated in CHIMERA is based upon the Multigroup Flux-Limited Diffusion (MGFLD) method. This current method basically uses only the zeroth angular moment of the Boltzmann equation and closes the system with terms dropped from the first angular moment to produce a diffusion-like equation. A flux-limiter is added to interpolate between the diffusive and free-streaming regimes, and to prevent the algorithm from computing acausal, i.e., faster than light transport, in regions where the neutrino mean free paths are large., 2023, Includes bibliography., Degree granted: Dissertation (PhD)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

One of the central issues in stability analysis for control systems is how robust a stability property is when external disturbances are presented. This is even more critical when a system is affected by time delay. Systems affected by time delays are ubiquitous in applications. Time delays add more challenges to the task of stability analysis, mainly due to the fact that the state space of a delay system is not a finite-dimensional Euclidean space anymore, but rather an infinite dimensional space of continuous functions defined on the delay interval. In this work, we investigate robust output stability properties for nonlinear systems affected by time delays and external disturbances. Frequently in applications, the requirement of stability properties imposed on the full set of state variables can be too strenuous or even unrealistic. This motivates one to consider robust output stability properties which are related to partial stability analysis in the classic literature. We start by formulating several notions on integral input-to-output stability and illustrate how these notions are related. We then continue to develop Lyapunov-Krasovskii type of results for such stability properties. As in the other context of Lyapunov stability analysis such as global asymptotic stability and input-to-state stability, a Lyapunov-Krasovskii functional is required to have a decay rate proportional to the magnitudes of the state variables or output variables on the whole delayed interval. This is a difficult feature when trying to construct a Lyapunov-Krasovskii functional. For this issue, we turn our efforts to Lyapunov-Krasovskii functional with a decay rate depending only on the current values of state variables or output variables. Our results lead to a type of Lyapunov-Krasovskii functionals that are more flexible regarding the decay rate, thereby leading to more efficient results for applications., 2023, Includes bibliography., Degree granted: Dissertation (PhD)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

Freshwater harmful algal blooms (HABs) are increasing in severity and frequency. These blooms are devastating to the communities surrounding these bodies of water due to their numerous health, economic, and environmental impacts (Hallegraeff et al. 1995; Smith 2003; O’Neil et al. 2012; Bláha et al. 2009; V. H. Smith et al. 1999). In Florida, runoff containing fertilizers, human wastes, or industrial wastes contribute to the eutrophication in these lakes and contribute to these freshwater blooms (Val H. Smith 2003; Heisler et al. 2008; O’Neil et al. 2012). M. aeruginosa, a toxic cyanobacterium, often devastates Lake Okeechobee. M. aeruginosa die off creates anoxic conditions and produces a toxin that causes major environmental loss. This project is aimed to increase knowledge on how organic phosphorus compounds affect the growth of the axenic M. aeruginosa and investigate the postulated interactome (Cook et al. 2020). Through these experiments, it was shown that axenic M. aeruginosa cannot utilize organic phosphorus compounds and therefore shows no growth when grown in this media. This research is critical to furthering our understanding of the mechanisms behind these blooms and to mitigating them., 2023, Includes bibliography., Degree granted: Thesis (MS)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

Coral reefs around the globe have undergone widespread degradation due to a myriad of natural and anthropogenic stressors. Climate warming, in particular, has emerged as an especially pressing threat, reshaping not only the biodiversity of coral-reef ecosystems worldwide, but also undermining the vital ecosystem services they provide. Yet amidst this decline, there is growing evidence that many coral species are expanding their ranges poleward into historically cooler subtropical and temperate marine environments thereby establishing critical refugia in response to climate warming. However, understanding the long-term viability and potential of these emerging refugia under ongoing climate change remains an area of active research, constrained by the temporal limitations of modern ecological studies. In addressing these challenges, this dissertation explores insights from a newly discovered late Holocene record of coral community development off southeast Florida, shedding light on historical coral range expansions, and providing critical context for assessing the future response of reef-building coral communities to continued climate warming. Using a combination of high-precision uranium-thorium dating and detailed paleoecological analysis of well-preserved subfossil coral skeletons, we provide new evidence that diverse coral communities dominated by Acropora spp. expanded to the nearshore hardbottom habitats off northern Broward County during a period of warming in the subtropical western Atlantic between 3500 and 1800 years before present. However, despite this historical precedent of range expansion in response to regional warming, modern comparisons reveal a significant shift towards low diversity coral assemblages dominated by stress-tolerant coral taxa, suggesting that ongoing range expansions may be constrained by new challenges that were absent during the late Holocene. These findings underscore the need for comprehensive conservation strategies informed by, 2023, Includes bibliography., Degree granted: Dissertation (PhD)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

Suaeda linearis is an edible halophyte crop with nutraceutical properties that is native to Florida. This study investigated how the biomass production and mineral content of aquacultured S. linearis was affected by harvest frequency during a 10-week period using four different harvest treatments. Under the first treatment (T1) plants received zero intermittent harvests, the second (T2) received harvests every five weeks, the third (T3) received harvests every 3.3 weeks, and the fourth (T4) received harvests every 2.5 weeks. The results indicate that biomass production and mineral content were both strongly affected by harvest treatment. Intermittent harvesting decreased biomass production and conversely, intermittent harvesting increased the quantities of certain desirable minerals in S. linearis. Early harvests of the study plants were small, suggesting that 13-15 weeks after germination is the earliest time a harvestable yield can be achieved from S. linearis., 2023, Includes bibliography., Degree granted: Thesis (MS)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

This experiment evaluated the effect of positively evaluative attributes on purchasing decisions by manipulating the Type of Repetition from a study phase to a test phase. Behavioral data and hemodynamic responses were measured using functional near-infrared spectroscopy (fNIRS) in 38 participants during a study task, where brand-name products and product specific attributes were processed, and during a test phase, where participants chose to purchase either new or previously processed products that were presented with either the same attribute, a different attribute, or no attribute. Results at test showed that repeating the association produced the highest accuracy in selecting the previously processed product and the highest hemodynamic activation. In contrast, presenting a different attribute at test produced the lowest accuracy and least hemodynamic activation, much like baseline. This hemodynamic difference between the same and different conditions was especially prevalent in the left hemisphere during the later time windows. These findings suggest that repeating the association biases purchase intention and produces hemodynamic repetition enhancement. In contrast, changing the association leads to interference and reduced selection of the processed product., 2023, Includes bibliography., Degree granted: Thesis (MA)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

This work encompasses the synthesis, analysis, and optimization of [3.2.1] all-carbon bridged bicyclic compounds, known as resveramorphs (RVM), Studies were conducted using a Caenorhabditis elegans model, where RVMs were tested for antiseizure capabilities. In both applications, RVMs proved potent with activities in the sub-nanomolar level in one case. A structure-activity relationship (SAR) was hypothesized for the identification of the pharmacophore. The six to seven step synthesis route towards the RVM analogues is discussed in further detail. The bicyclization of the RVMs is achieved through a reductive aldol reaction. The reaction suffers from selectivity issues leading to multiple bicyclic products. By following a one-factor-at-a-time (OFAT) methodology, attempts at optimization for this reaction were made, however, despite important gains, the overall yields of the bicyclic product remain low. Other products from this reaction have been used to understand the reaction mechanism, which will be the basis for future efforts to further optimize this key step., 2023, Includes bibliography., Degree granted: Thesis (MS)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

Complex life cycles are common across parasite taxa and frequently require trophic transfer of parasites from prey to predator; however, studies on parasite-host interactions often neglect variation in parasite life histories. Here I use two focal freshwater digenetic trematode species, Halipegus occidualis tongueworms and Haematoloechus complexus lungworms, as an empirical system to investigate how parasite life history traits drive host-parasite interactions across the life cycle. To examine how parasite life history and host ecology influence parasite genetic patterns, I characterized the genetic diversity of within-host infrapopulations, as well as overall population genetic structure, of sympatric tongueworm and lungworm populations. Infection load and genetic diversity of host-level parasite infrapopulations increased with host trophic level, highlighting the benefits of trophic transfer and multihost life cycles. Concurrently, first intermediate host population dynamics and dispersal ability played a role in predicting population-level parasite genetic diversity and structure., 2023, Includes bibliography., Degree granted: Dissertation (PhD)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

Recent success of mindfulness-based interventions in adult and clinical populations, as well as in classroom settings, has spurred the need for a more thorough understanding of mindfulness as a trait that can affect early development of self-regulatory characteristics. The current study used previously collected data on 4th and 5th graders to explore the relationships between trait mindfulness, self-regulation, and stress reactivity, measured using cortisol levels. Self-regulation was measured using effortful control (attention, inhibitory control, and activation control), conscientiousness, agreeableness, negative emotion regulation, and openness to experience. Cortisol findings were significant for negative emotion regulation. Results revealed several significant positive associations between trait mindfulness and several self-regulatory characteristics among people who did and did not respond to a stressor. Further research is necessary to tease apart the unique contribution of individual self-regulatory characteristics, including trait mindfulness, on stress reactivity., 2023, Includes bibliography., Degree granted: Thesis (MA)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

The goal of this dissertation is to estimate the precise asymptotics for the number of geometric equivalence classes of Morse functions on the 2-sphere. Our approach involves utilizing the Lagrange inversion formula, Cauchy’s coefficient formula, and the saddle point method for the asymptotic analysis of contour integrals to analyze the generating function derived by L. Nicolaescu, expressed as the inverse of an elliptic integral. We utilize complex analysis, nonlinear functional analysis in infinite sequence spaces, and interval arithmetic to write all the necessary MATLAB programs that validate our results. This work answers questions posed by Arnold and Nicolaescu, furthering our understanding of the topological properties of Morse functions on two-dimensional manifolds. It also demonstrates the effectiveness of a computer assisted approach for asymptotic analysis., 2023, Includes bibliography., Degree granted: Dissertation (PhD)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

A hypothesized model of spindle organization of thalamic and hippocampal spike dynamics (Figure 1) suggests that sparsity operates in spindles as an essential component of thalamic activity that could be contributing to flexibility in learning (Varela & Wilson, 2020). We asked the question of whether sparse spindle-like (10Hz non-rhythmic) or 10Hz rhythmic activity in thalamic cells of the reuniens nucleus influence cognitive flexibility during learning after sleep. By comparing the two stimulation protocols (“nonrhythmic” and “rhythmic”), we tested if disrupting the characteristic sparsity reveals any changes in flexibility during learning after sleep. Results showed that sleep accompanied 10Hz rhythmic optogenetic stimulation of thalamic nucleus reuniens impaired rule-switching (or set-shifting) performance and disrupted the sleep enhancing rule-switch associated increase in vicarious trial and error (VTE), which we used as a metric for deliberation. We found that rule-switching was associated with a subsequent increase in VTE, as were incorrect choices, and when rats subsequently made correct choices. Instead, stimulating against the endogenous thalamocortical spindle oscillation (i.e. sleep accompanied 10Hz rhythmic optogenetic stimulation) resulted in a significant disruption in post-sleep performance and VTE during, but not prior to, rule-switching. Lastly, optogenetic 10Hz stimulation of the thalamic nucleus reuniens did not affect sleeping or waking behavior during the sleep box session but it did show a clear though nonsignificant increase in waking head velocities; thus, changes in cognitive flexibility and VTE cannot be explained by any changes in sleep itself, but rather due to the after-effects the specific patterns of 10Hz optogenetic stimulation in thalamic nucleus reuniens applied during sleep had on cognition., 2023, Includes bibliography., Degree granted: Dissertation (PhD)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

Storms in the North Atlantic Ocean are observed on a continual basis yearly. Storm trajectories exhibit random behavior and are costly to society. Data from the National Oceanic and Atmospheric Administration (NOAA) contains every storm’s track from the year 1851 to 2022. Data of each storm’s track can aid in decision making regarding their behavior. In this article, data analysis is performed on historical storm tracks during the years 1966 to 2022, where access to satellite information is available. Analysis on this data will be used to determine if the storms’ trajectory is statistically dependent on other storm’s trajectories at varying distances in space. The proposed model is a spatial statistical model that is fitted on an in-sample data set to determine the spatial relationship for storm trajectories at all pairwise directions or orientations. Afterwards, the model is assessed on an out-of-sample test data set for performance evaluation., 2023, Includes bibliography., Degree granted: Thesis (MS)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

We examine how best to associate quantum states of a single particle to modes of a narrowly collimated beam of classical radiation modeled in the paraxial approximation, both for scalar particles and for photons. Our analysis stresses the importance of the relationship between the inner product used to define orthogonal modes of the paraxial beam, on the one hand, and the inner product underlying the statistical interpretation of the quantum theory, on the other. While several candidates for such an association have been proposed in the literature, we argue that one of them is uniquely well suited to the task. Specifically, the mapping from beam modes to ”henochromatic” fields on spacetime is unique within a large class of similar mappings in that it is unitary in a mathematically precise sense. We also show that the single-particle quantum states associated to the orthogonal modes of a classical beam in the henochromatic approach are not only orthogonal, but also complete in the quantum Hilbert space., 2023, Includes bibliography., Degree granted: Dissertation (PhD)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

The goal of this dissertation was to examine the fate and fragmentation of plastic debris in the marine environment and characterize the microbial communities colonizing naturally occurring substrates and geologically recent plastic inputs in the ocean using analytical chemistry and genomic techniques. Altogether, the data presented herein reveal the presence of heretofore undescribed plastic accumulation zones in the ocean and depict a stark contrast in microbial traits between early and mature plastic biofilm stages. These data further suggest that emergent plastic biofilm properties can be forecasted across environmental gradients, with the largescale genomic characteristics of early colonizers varying little across conditions. Chapter I of this thesis is an introduction to the current body of work regarding the plastisphere. Chapter II explores the ‘cradle to grave’ fragmentation, transformation, and transport of model microplastic particles and single-use plastic items in an artificial beach setting. Chapter III presents the first metagenomic insights into early biofilm formation on virgin microplastic surfaces in the marine environment and how early colonizers self-assemble, compared to mature, taxonomically, and metabolically diverse biofilms residing on free-drifting plastic pollution. Chapter IV further investigates microbial adaptations for initial colonization of virgin control and plastic surfaces and examines biofilm assemblage dynamics by employing metagenomics on a 16-day time series in a wastewater treatment facility. Chapter V synthesizes observations from the previous core chapters and discusses what these findings mean in a broader ecological and evolutionary perspective. Appendix 1 is a reprint of the manuscript describing the distribution of microplastics beneath the inner and outer plastic accumulation zones of the South Atlantic Subtropical Gyre. Appendix 2 is a submitted manuscript detailing the isolation, characterization, and selective adap, 2023, Includes bibliography., Degree granted: Dissertation (PhD)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

Animals face both natural and sexual selection pressures, and at times, these pressures conflict with one another. This results in a tradeoff between sexual and natural selection. In my thesis, I examine aspects of Bachman’s sparrows’ behavior and morphology in relation to weather conditions in light of these two conflicting pressures. Large bill size is selected for by the natural selection pressures of thermoregulation. Smaller bills are selected for by the sexual selection pressures of song quality. Both thermoregulation and song are important behaviors/processes that have fitness implications. By looking at bill size in relation to thermoregulatory ability and song quality I examined the tradeoff between these two selection pressures acting on the bill of Bachman’s sparrows, 2023, Includes bibliography., Degree granted: Thesis (MS)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

The current study examined the association between retrospectively recalled paternal investment and current levels of commitment readiness in young adults. Various aspects of the participants’ relationship with their fathers during childhood were measured in a sample of 250 undergraduate students. Participants were also asked questions about how ready they are to be involved in a committed romantic relationship. The results did not support the main hypotheses: there were no significant associations between retrospectively recalled paternal investment and commitment readiness. Exploratory analyses revealed that attachment avoidance was significantly negatively correlated with both paternal investment, including measures of nurturant fathering and father involvement, and commitment readiness., 2023, Includes bibliography., Degree granted: Thesis (MA)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

This study examined the environmental and anthropogenic factors that may influence loggerhead sea turtle nest site selection and how these factors vary between successful nesting attempts and false crawls on a high-density sea turtle nesting beach in Boca Raton, Florida. Beach morphology, sand texture, and nests’ proximity to artificial structures were measured using a combination of drone-based photogrammetry, traditional surveys with Real Time Kinematic Global Positioning System (RTK GPS), and sediment granulometry. Proximity to dune crossover stairs was significantly different between nests and false crawls, and the probability of a false crawl occurring decreased as proximity to dune crossover stairs increased. The results of this study will provide researchers with a new tool for nest monitoring and a better understanding of the microhabitat cues that may influence loggerhead sea turtle nest site selection and aid in guiding beach and sea turtle management decisions., 2023, Includes bibliography., Degree granted: Thesis (MS)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

The goal of this project is to gain access to valuable genetic information that will be utilized to create a genetics-based selective breeding program. This selective breeding program will be implemented to produce and maintain a healthy and diverse breeding stock of the Florida Pompano Trachinotus carolinus. The Florida Pompano is a popular food fish found in abundance off Florida's east and west coasts. There has been interest in the aquaculture of this species for decades with minimal success. With recent improvements in aquaculture systems and nutrition, now is the time to bring this fish to commercialization. The main research objectives of this study are to create a bioinformatics workflow to generate a draft whole-genome of the Florida Pompano, identify variation sites within this genome, and run a comparative analysis with two closely related Trachinotus species, Permit T. falcatus and Palometa T. goodei. These two species were chosen because they are found in the same environment as the Florida Pompano but grow to substantially different sizes. To sequence and assemble the whole genome of the Florida Pompano, a hybrid method was applied using long and short-read sequencing technologies. The draft genome was found to be 733.5 Mb in length with a total of 26,891 protein-coding genes. Sites of variation within this assembled genome were identified using a 2b-RAD sequencing method on 62 individuals collected off Florida’s east and gulf coasts., 2023, Includes bibliography., Degree granted: Dissertation (PhD)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

The communication in the nervous system is a pharmacological balance between excitatory and inhibitory signals, and seizure behavior is one of the most common manifestations of when an imbalance occurs. Environmental toxins can cause significant disruption of excitation-inhibition balance, but while some toxins, like nerve agents, have known targets and require novel antidotes, some have unknown neurobiological mechanisms and require exploration. Of particular concern, there is little knowledge on how herbicides may affect neurological signaling. Glyphosate, the world’s most popular herbicide, was found to be in 80% of people’s urine, and since it is so prevalent, it is critical to understand its impact on both excitatory and inhibitory signaling. We used an electroshock assay developed for C. elegans to uncover evidence that glyphosate, and the commercial formula Roundup, disrupted the excitation-inhibition balance by blocking GABA-A receptors. This presented a novel hypothesis of an inhibitory neurobiological target for glyphosate. As glutamate is the major excitatory neurotransmitter in the human central nervous system, an electrophysiology assay using Drosophila was used and found that Roundup, but not glyphosate, reduced synaptic viability. This result directs attention to the undisclosed adjuvant component which may have a significant effect on synaptic transmission, though the exact mechanism requires further investigation., 2023, Includes bibliography., Degree granted: Dissertation (PhD)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

Fibropapillomatosis (FP) is a tumor disease that has reached panzootic proportions in green turtles (Chelonia mydas). FP is associated with chelonid alphaherpesvirus 5, although the etiology of FP is likely multifactorial, since high FP prevalence is often observed in degraded habitats. However, specific environmental cofactors for tumor development remain unknown. To explore this, I collated statewide green turtle stranding data from 2000–2020 to evaluate spatiotemporal trends of FP in Florida, and co-analyzed these data alongside patterns of river flow, chlorophyll-a (Chla), sea surface temperature (SST), El Niño (ENSO), and red tide (HAB). I found that FP was stable during 2000–2020. HAB (positively) and SST (negatively) correlated with statewide FP prevalence, as well as several interactions between various factors. These results suggest that SST and HABs may act as cofactors in the development of FP, and future work should be equally interdisciplinary in their investigation of this multifactorial disease, 2023, Includes bibliography., Degree granted: Thesis (MS)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

The current work investigates the identification of novel drugs that have the potential to be suitable anti-malarials against Plasmodium falciparum-infected erythrocytes. The growing resistance to current therapeutic modalities necessitates the development of new emerging and effective compounds. The target of these compounds in this work will be PfGARP (P. falciparum glutamic-acid-rich protein), a surface antigen of infected erythrocytes (IEs) found only in P. falciparum that has been recently recognized as a valuable drug target and vaccine candidate. Using a two-step approach designed in our lab, we were able to efficiently screen large libraries of small molecules provided by ChemBridge and the Torrey Pines Institute for Molecular Studies (TPIMS). We base the current work on our preliminary results, obtained with a subset of 6,400 compounds of DIVERSet library, reasoning that there may be other individual compounds that can be identified as having equal or greater parasiticidal activity. In this work, initial screening of the ChemBridge DIVERSet library subset of other 3,600 compounds organized into compound mixtures using Bio-Plex technology resulted in the identification of the most active mixtures (HITS-1), which were further deconvoluted into simpler mixtures (HITS-2). Screenings of HITS-2 yielded two mixtures of interest that did not portray any noticeable binding inhibition, and the deconvolution process was thus forfeited., 2023, Includes bibliography., Degree granted: Thesis (MS)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

Stony coral tissue loss disease (SCTLD) emerged in 2014 and has since spread across Florida’s Coral Reef (FCR) and the Caribbean. This thesis is part of a larger project assessing the efficacy of restoring SCTLD-susceptible corals Montastraea cavernosa, Orbicella faveolata, and Pseudodiploria clivosa in SCTLD endemic areas. As part of Florida’s largest coral restoration experiment to date, 1,152 cement bases with 5,760 coral fragments from 99 source colonies were outplanted across six regions throughout FCR and monitored monthly over two years for survival, disease, and growth. Before outplanting, coral tissue samples were collected for high-resolution 2bRAD and ITS2 sequencing to genotype the corals and characterize their initial algal symbiont communities. Neither host genetic lineages nor algal symbiont types significantly affected SCTLD susceptibility or survival, negating the hypothesis of SCTLD-resistant “super coral” lineages. Results from this study will inform the feasibility and design of future coral restoration efforts in SCTLD endemic zones to maintain or enhance coral biodiversity., 2023, Includes bibliography., Degree granted: Thesis (MS)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

Tau, a microtubule-associated protein, is involved in more than 20 different tauopathic disorders characterized by aberrant intracellular aggregation of tau in the brain. However, it is still unclear how this highly soluble tau protein aggregates inside the brain. Thus, understanding the mechanistic details of tau aggregation is critical for unraveling the underlying pathology of tauopathies and developing effective strategies to inhibit tau aggregation. Herein, we investigated the aggregation of a novel 20-residue model peptide, tau₂₉₈₋₃₁₇, derived from the key microtubule-binding domain of the full sequence tau. Our study demonstrates that tau₂₉₈₋₃₁₇ highly mimics full-length tau's physical and aggregation properties. The fibrillation of the peptide is strongly dependent on external factors. The presence of polyanionic heparin (Hep) significantly promotes the aggregation of this peptide to form amyloid fibrils. The Hep-induced aggregation is sensitive to the ionic strength of the solution, suggesting an important role of electrostatic interactions in the mechanism of Hep-mediated aggregation. In addition, two positively charged polysaccharides, chitosan (CHT) and its quaternary derivative N-trimethyl chitosan (TMC), effectively inhibit Hep-induced aggregation of tau₂₉₈₋₃₁₇ in a concentration-dependent manner. Attractive electrostatic interactions between the positively charged moieties in CHT/TMC and the negatively charged residues of Hep play a critical role in inhibiting Hep–peptide interactions and suppressing peptide aggregation., 2023, Includes bibliography., Degree granted: Dissertation (PhD)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

The current study examined how viewing an event from different perspectives (eye-level and elevated) at both encoding and retrieval changes the recognition of that event. Specifically, participants were shown various manipulations to the scenarios that they witnessed at encoding. The primary focus of the study was the participants’ ability to identify old scenarios along with scenarios that had been manipulated through differences in character clothing, object placement, or temporal order of events, while still resembling the old scenario in every other way. No support was found to support the prediction that perspective at either encoding or retrieval had an effect on recognition of the scenario or the different manipulation types. An exploratory analysis revealed a trend towards significance for perspective at encoding. An eye-level perspective at encoding was more likely to result in a higher rejection rate for temporal manipulations., 2023, Includes bibliography., Degree granted: Thesis (MA)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

Sea level rise threatens loggerhead sea turtle (Caretta caretta) nests laid close to the high tide line (HTL) with inundation from washover. Boca Raton, Florida is a relatively steep, dynamic beach with changes in beach morphology even during nonactive hurricane seasons. One potential solution to conserve sea turtle nests is to relocate nests laid at or below the HTL closer to the dune. In this study, I examined reproductive success for in situ vs relocated nests. Relocation did not decrease reproductive success, while nests left near the HTL were at risk of washout. During a dry season, nests that experienced one to three days of washover had significantly higher reproductive success than nests that experienced no washover. Relocation can be a useful method to preserve nests against sea level rise, but nonrelocated nests near the HTL may sometimes benefit from washover to cool the nests during hot and dry years., 2023, Includes bibliography., Degree granted: Thesis (MS)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

The ability to recognize human actions is essential for individuals to navigate through their daily life. Biological motion is the primary mechanism people use to recognize actions quickly and efficiently, but their precision can vary. The development of Artificial Neural Networks (ANNs) has the potential to enhance the efficiency and effectiveness of accomplishing common human tasks, including action recognition. However, the performance of ANNs in action recognition depends on the type of model used. This study aimed to improve the accuracy of ANNs in action classification by incorporating biological motion information into the input conditions. The study used the UCF Crime dataset, a dataset containing surveillance videos of normal and criminal activity, and extracted biological motion information with OpenPose, a pose estimation ANN. OpenPose adjusted to create four condition types using the biological motion information (image-only, image with biological motion, only biological motion, and coordinates only) and used either a 3-Dimensional Convolutional Neural Network (3D CNN) or a Gated Recurrent Unit (GRU) to classify the actions. Overall, the study found that including biological motion information in the input conditions led to higher accuracy regardless of the number of action categories in the dataset. Moreover, the GRU model using the 'coordinates only' condition had the best accuracy out of all the action classification models. These findings suggest that incorporating biological motion into input conditions and using numerical format input data can benefit the development of accurate action classification models using ANNs., 2023, Includes bibliography., Degree granted: Thesis (MA)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection

To better understand the N170 event related potential (ERP), we examined how factors such as participant gender and implicit racial bias might reflect upon amplitude and latency. White male (18) and female (34) participants performed an implicit association test (IAT) and Simple viewing EEG task with own-race White and other-race Asian faces. We were able to make several conclusions from the data. (1a) Participants generally showed an implicit racial bias favoring their own race group. (1b) The degree of this implicit racial bias did not differ between male and female participants. (2) Male, compared to female, participants expressed longer N170 latencies but similar amplitudes. (3) Lower compared to higher levels of implicit racial bias did not appear to influence the N170. (4) Participant gender, stimulus race, and implicit racial bias did not interact to influence the N170., 2023, Includes bibliography., Degree granted: Thesis (MA)--Florida Atlantic University, 2023., Collection: FAU Electronic Theses and Dissertations Collection