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Full-Text Articles in Physical Sciences and Mathematics

Factors Affecting Apothecia Production And Primary Infection By Monilinia Vaccinii-Corymbosi On Vaccinium Angustifolium, Ian Leonard May 2023

Factors Affecting Apothecia Production And Primary Infection By Monilinia Vaccinii-Corymbosi On Vaccinium Angustifolium, Ian Leonard

Electronic Theses and Dissertations

Mummy berry, caused by Monilinia vaccinii-corymbosi (MVC), is a prolific disease of Vaccinium angustifolium (wild blueberry) leading to decreased yield in wild blueberry fields throughout the Downeast (DE) and Midcoast (MC) regions of Maine (ME). This study aimed to identify factors affecting primary inoculum production and infection by MVC on wild blueberry, and what bud stages of wild blueberry are most susceptible to infection. Through common garden (CGE), field and incubation experiments conducted in 2021 and 2022, factors affecting carpogenic germination of MVC pseudosclerotia and relationships between susceptible wild blueberry buds and environmental factors were analyzed. The CGE conducted in …


Synthesis Of A Pharmaceutical Precursor From Bioderived Glucose, Justin O. P. Waters May 2023

Synthesis Of A Pharmaceutical Precursor From Bioderived Glucose, Justin O. P. Waters

Electronic Theses and Dissertations

Medication costs in the U.S. are high, and manufacturing and production comprise the largest share of those costs. As the world continues to shift to more sustainable methods of production, there are opportunities to reduce these costs through green synthesis. A large number of pharmaceuticals are derived from a precursor (S-3-hydroxy-gamma-butyrolactone ‘HBL’). Drugs that treat cancer, antivirals, antibacterial drugs, and some cholesterol medications all can be derived from HBL. Currently, HBL is almost exclusively derived from petroleum through an expensive and resource intensive process. Until recently, ‘green’ efforts to derive HBL from biomass have been plagued with many of the …


Areas Of Same Cardinal Direction, Periyandy Thunendran May 2023

Areas Of Same Cardinal Direction, Periyandy Thunendran

Electronic Theses and Dissertations

Cardinal directions, such as North, East, South, and West, are the foundation for qualitative spatial reasoning, a common field of GIS, Artificial Intelligence, and cognitive science. Such cardinal directions capture the relative spatial direction relation between a reference object and a target object, therefore, they are important search criteria in spatial databases. The projection-based model for such direction relations has been well investigated for point-like objects, yielding a relation algebra with strong inference power. The Direction Relation Matrix defines the simple region-to-region direction relations by approximating the reference object to a minimum bounding rectangle. Models that capture the direction between …


Development And Applications Of Similarity Measures For Spatial-Temporal Event And Setting Sequences, Fuyu Xu May 2023

Development And Applications Of Similarity Measures For Spatial-Temporal Event And Setting Sequences, Fuyu Xu

Electronic Theses and Dissertations

Similarity or distance measures between data objects are applied frequently in many fields or domains such as geography, environmental science, biology, economics, computer science, linguistics, logic, business analytics, and statistics, among others. One area where similarity measures are particularly important is in the analysis of spatiotemporal event sequences and associated environs or settings. This dissertation focuses on developing a framework of modeling, representation, and new similarity measure construction for sequences of spatiotemporal events and corresponding settings, which can be applied to different event data types and used in different areas of data science. The first core part of this dissertation …


Art-At-Work: Creativity And Social Practice As Collaborative, Interdisciplinary Research, Anna Martin May 2023

Art-At-Work: Creativity And Social Practice As Collaborative, Interdisciplinary Research, Anna Martin

Electronic Theses and Dissertations

Art-At-Work describes the tools, vocabularies, strategies and experiences that render the emergent spaces of collaborative interdisciplinary research. This body of work generates a story board for the unfolding narrative of a studio-laboratory practice where artists research with scientists and scientists create with artists. The long-term goals and short-term deliverables of this research focus attention toward the process of building connection, tools and space for future work that creates channels for collaboration among disciplines. With each conversation, concept map, prototype, reflection and iteration, creatives and researchers are exploring the spaces among fields of practice by generating ways of sharing experiences that …


Horizon Content Knowledge And Its Integration Into Physics Education Research: Case Study Analysis On Physical Science And Physics Teachers, Trevor A. Robertson May 2023

Horizon Content Knowledge And Its Integration Into Physics Education Research: Case Study Analysis On Physical Science And Physics Teachers, Trevor A. Robertson

Electronic Theses and Dissertations

Teachers focused on just one year of instruction may neglect what students need most– a coherent structure of learning across disciplines that advances students’ understanding. The topic of coherence has been a major motivator for education research, including investigations in student- teacher interactions, epistemological beliefs, and large-scale curricular reform. One framework of knowledge, horizon content knowledge (HCK), can aid in describing the knowledge a teacher needs to see beyond their own instruction and provide a coherent structure for students.

While horizon content knowledge exists in one of the most widely adopted teacher frameworks of knowledge in mathematics, mathematical knowledge for …


Effects Of Fibril Morphology And Interfacial Interactions On The Behavior Of Polymer-Grafted Cellulose Nanofibril Reinforced Thermoplastic Composites, Peter V. Kelly May 2023

Effects Of Fibril Morphology And Interfacial Interactions On The Behavior Of Polymer-Grafted Cellulose Nanofibril Reinforced Thermoplastic Composites, Peter V. Kelly

Electronic Theses and Dissertations

Mechanically refined cellulose nanofibrils (CNFs) promise to be a high-volume, sustainable, nanoscale reinforcement for thermoplastic composites. They are currently held back by poor interfacial interactions with composite matrices, energy intensive drying, and drying induced fibril aggregation. In this dissertation, we explored how a grafting-through polymerization scheme modified the surface of CNFs with a wide variety of commodity polymers and overcame many of these technical challenges.

The first phase of the research was concerned with characterizing the unique morphology of these CNFs as a function of refinement energy. This characterization was employed to understand how the materials’ morphologies affected their interfacial …


Quantum Mechanical Studies Of Water Splitting Reaction With (Zno)3 Nanoclusters As Catalysts, Duwage C. Perera May 2023

Quantum Mechanical Studies Of Water Splitting Reaction With (Zno)3 Nanoclusters As Catalysts, Duwage C. Perera

Electronic Theses and Dissertations

With the current energy crisis, H2 production through the water-splitting reaction has drawn attention recently. In this thesis, I studied the structural (geometry) and electronic properties (vertical detachment energy and electron affinity) of ZnO monomers and dimers using density functional theory. ZnO is a metal oxide with a 3.37 eV band gap and can be a commercially cheaper photocatalyst in hydrogen (H2) production. The B3LYP/DGDZVP2 pair was selected after investigating different pairs of exchange functionals and basis sets to study the hydration, hydrolysis, and water-splitting reaction. The singlet-triplet energy gaps of small (ZnO)n clusters (n=1-6) of …


Hybrid Power Spectral And Wavelet Image Roughness Analysis, Basel White May 2023

Hybrid Power Spectral And Wavelet Image Roughness Analysis, Basel White

Electronic Theses and Dissertations

The Two-Dimensional Wavelet Transform Modulus Maxima (2D WTMM) sliding window methodology has proven to be a robust approach, in particular for the extraction of the Hurst (H) roughness exponent from grayscale mammograms. The power spectrum is a computational analysis based on the Fourier transform that can be used to estimate the roughness of a scale-invariant image or region via the calculation of H. We aim to examine how the calculation of H in fractional Brownian motion (fBm) images and mammograms can be improved. fBm images are generated for H ∈ [0.00,1.00] for testing through the previous 2D …


Developing An Enhanced Forest Inventory In Maine Using Airborne Laser Scanning: The Role Of Calibration Plot Design And Data Quality, Stephanie Willsey May 2023

Developing An Enhanced Forest Inventory In Maine Using Airborne Laser Scanning: The Role Of Calibration Plot Design And Data Quality, Stephanie Willsey

Electronic Theses and Dissertations

Forests provide essential ecosystem services such as carbon sequestration, clean water, lumber, and more. It is important that foresters be able to collect accurate forest inventories, especially in a changing climate. Foresters need to know what is in the forest not only to manage for the economic benefits, but also to manage for social acceptability and ecological soundness to prevent further degradation of these ecosystem services. One way to collect accurate and precise forest inventories is through the utilization of remote sensing products. These enhanced forest inventories (EFIs) can be done at varying resolutions that are contingent on the plot …


Optimizing Strategies To Hydraulically Plant Atlantic Salmon Eggs Based On Fry Dispersal Patterns, Ernest J. Atkinson May 2023

Optimizing Strategies To Hydraulically Plant Atlantic Salmon Eggs Based On Fry Dispersal Patterns, Ernest J. Atkinson

Electronic Theses and Dissertations

The Gulf of Maine Distinct Population Segment of Atlantic Salmon has suffered from habitat loss and exploitation over the last century. Hatchery supplementation has prevented the extirpation of the species, but stocking methods represent tradeoffs between survival, domestication, and logistics. Egg planting, the use of eyed embryos, maximizes natural rearing opportunities which can be important for adaptation. This method, however, is logistically demanding and requires significant labor over large spatial, but short temporal, scales dictated by the ontogeny of the fish. However, the survival and dispersal behavior of Atlantic Salmon fry immediately after emergence from eggs planted in artificial nests …


Influence Of Platinum Nanoparticles On Ionic Transport And Hydrogen Reactivity Of Yttria-Stabilized Zirconia Thin Films, Firas Mahyob May 2023

Influence Of Platinum Nanoparticles On Ionic Transport And Hydrogen Reactivity Of Yttria-Stabilized Zirconia Thin Films, Firas Mahyob

Electronic Theses and Dissertations

Yttria-stabilized zirconia (YSZ) is a widely used ceramic material in solid oxide fuel cells, oxygen sensors, and sensing applications due to its high ionic conductivity, chemical inertness, and thermal stability. YSZ is promising active coating for use in miniaturized harsh environment wireless surface acoustic sensors to monitor gases such as H2. Adding catalytic Pt nanoparticles can enhance gas reactivity and lead to associated film conductivity changes.

In this work, thin films with an (8% Y2O3 - 92% ZrO2) composition were deposited onto piezoelectric langasite substrates using RF magnetron sputtering in Ar:O2 - …


The Future Is Now In Twisted Coil Polymer Actuators (Tcpa), Ryan Ronquillo May 2023

The Future Is Now In Twisted Coil Polymer Actuators (Tcpa), Ryan Ronquillo

Electronic Theses and Dissertations

This thesis aimed to fabricate and test twisted coiled polymer actuators (TCPA) to understand the mechanical and thermal aspects of this artificial muscle fiber. The purpose of this thesis was to find a linear relationship using the LVDT sensor, fabricating TCPA fibers, and interpreting the data. The project tested whether nylon/polymer could be used as a better artificial muscle fiber.

This research accomplished three goals: (1) designing and fabricating a system capable of creating supercoiled muscle fibers consistently, (2) calibrating the Linear Variable Differential Transformer (LVDT) and Core, and (3) analyzing/interpreting the data of the Twisted Coiled Polymer Actuators (TCPA) …


Dolphin Behavioral Responses To Uncrewed Aerial Systems As A Function Of Exposure, Height, And Type, Savannah Damiano May 2023

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

Electronic Theses and Dissertations

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


Use Of Space And Foraging Behavior Of Loggerhead Shrikes In Urban Areas, Katie Anne Maddox May 2023

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

Electronic Theses and Dissertations

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

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


Leadership Development In Education For Sustainable Development: Evaluation Of Higher Education Students In Sustainable Development Programs, Michelle Dzurenda May 2023

Leadership Development In Education For Sustainable Development: Evaluation Of Higher Education Students In Sustainable Development Programs, Michelle Dzurenda

Electronic Theses and Dissertations

The United Nations Department of Economic and Social Affairs (UN DESA) has been working decades towards reaching Sustainable Development Goals (SDGs) to create peace and prosperity for people and the planet. The 2030 Agenda was created as an urgent call to action, a global partnership, and a comprehensive plan to work towards the 17 SDGs. For this study, the focus is on Goal 4- quality education and the impact of leadership on Education for Sustainable Development (ESD). Leadership on ESD has been a more recent topic and under researched. By making advancements in leadership on ESD there will be positive …


Identifying And Analyzing Multi-Star Systems Among Tess Planetary Candidates Using Gaia, Katie E. Bailey May 2023

Identifying And Analyzing Multi-Star Systems Among Tess Planetary Candidates Using Gaia, Katie E. Bailey

Electronic Theses and Dissertations

Exoplanets represent a young, rapidly advancing subfield of astrophysics where much is still unknown. It is therefore important to analyze trends among their parameters to learn more about these systems. More complexity is added to these systems with the presence of additional stellar companions. To study these complex systems, one can employ programming languages such as Python to parse databases such as those constructed by TESS and Gaia to bridge the gap between exoplanets and stellar companions. Data can then be analyzed for trends in these multi-star exoplanet systems and in juxtaposition to their single-star counterparts. This research was able …


Development Of Three Novel Edna Assays For Detecting Coastal Sharks, Kristina Dawn Flanigan May 2023

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

Electronic Theses and Dissertations

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


Modeling, Simulation And Control Of Microrobots For The Microfactory., Zhong Yang May 2023

Modeling, Simulation And Control Of Microrobots For The Microfactory., Zhong Yang

Electronic Theses and Dissertations

Future assembly technologies will involve higher levels of automation in order to satisfy increased microscale or nanoscale precision requirements. Traditionally, assembly using a top-down robotic approach has been well-studied and applied to the microelectronics and MEMS industries, but less so in nanotechnology. With the boom of nanotechnology since the 1990s, newly designed products with new materials, coatings, and nanoparticles are gradually entering everyone’s lives, while the industry has grown into a billion-dollar volume worldwide. Traditionally, nanotechnology products are assembled using bottom-up methods, such as self-assembly, rather than top-down robotic assembly. This is due to considerations of volume handling of large …


Immersive Learning Environments For Computer Science Education, Dillon Buchanan May 2023

Immersive Learning Environments For Computer Science Education, Dillon Buchanan

Electronic Theses and Dissertations

This master's thesis explores the effectiveness of an educational intervention using an interactive notebook to support and supplement instruction in a foundational-level programming course. A quantitative, quasi-experimental group comparison method was employed, where students were placed into either a control or a treatment group. Data was collected from assignment and final grades, as well as self-reported time spent using the notebook. Independent t-tests and correlation were used for data analysis. Results were inconclusive but did indicate that the intervention had a possible effect. Further studies may explore better efficacy, implementation, and satisfaction of interactive notebooks across a larger population and …


Artificial Dendritic Neuron: A Model Of Computation And Learning Algorithm, Zachary Hutchinson May 2023

Artificial Dendritic Neuron: A Model Of Computation And Learning Algorithm, Zachary Hutchinson

Electronic Theses and Dissertations

Dendrites are root-like extensions from the neuron cell body and have long been thought to serve as the predominant input structures of neurons. Since the early twentieth century, neuroscience research has attempted to define the dendrite’s contribution to neural computation and signal integration. This body of experimental and modeling research strongly indicates that dendrites are not just input structures but are crucial to neural processing. Dendritic processing consists of both active and passive elements that utilize the spatial, electrical and connective properties of the dendritic tree.

This work presents a neuron model based around the structure and properties of dendrites. …


An Analysis Of Changes In Seasonal Dynamics And Generational Differences In The Maine Lobster Fishery, Emily Fitting May 2023

An Analysis Of Changes In Seasonal Dynamics And Generational Differences In The Maine Lobster Fishery, Emily Fitting

Electronic Theses and Dissertations

The American lobster (Homarus americanus) supports the most valuable single species fishery in the US. Lobster landings have been increasing steadily for the last three decades, but before that landings were more variable. The high value of the lobster fishery combined with the decline of other commercially important species in this region has created increasing dependence on the resource, and previous research questions the resilience of the fishery in the face of social and environmental changes.

Important lobster life history processes, including migration patterns, growth rates, and reproduction, are driven by ocean bottom temperature, which creates a strong seasonal cycle …


Enestr¨Om-Kakeya Type Results For Complex And Quaternionic Polynomials, Matthew Gladin May 2023

Enestr¨Om-Kakeya Type Results For Complex And Quaternionic Polynomials, Matthew Gladin

Electronic Theses and Dissertations

The well known Eneström-Kakeya Theorem states that: for P(z)=∑i=0n ai zi, a polynomial of degree n with real coefficients satisfying 0 ≤ a0 ≤ a1 ≤ ⋯≤ an, all zeros of P(z) lie in |z|≤1 in the complex plane. In this thesis, we will find inner and outer bounds in which the zeros of complex and quaternionic polynomials lie. We will do this by imposing restrictions on the real and imaginary parts, and on the moduli, of the complex and quaternionic coefficients. We also apply similar restrictions on complex polynomials with …


New Reports Of Smilodon And Panthera From North American Cave Sites With Reviews Of Taxonomy, Biogeography, And History, Matthew Bushell May 2023

New Reports Of Smilodon And Panthera From North American Cave Sites With Reviews Of Taxonomy, Biogeography, And History, Matthew Bushell

Electronic Theses and Dissertations

In this study, three new reports of large felids from the Pleistocene are presented and discussed. A single partial left dentary from Jawbone Cave represents the first confirmed presence of S. fatalis in east Tennessee and was sampled for radiocarbon dating. Wind Tunnel and Chilly Bowl Cave are among the first records of P. onca to be identified confidently from Arkansas. Chilly Bowl Cave also produced two trackways attributable to Panthera sp., one set potentially belonging to P. atrox. In addition to the description of these remains and the caves they were found in, taxonomic histories for both S. fatalis …


A Programmatic Geographic Information Systems Analysis Of Plant Hardiness Zones, Andrew Bowen May 2023

A Programmatic Geographic Information Systems Analysis Of Plant Hardiness Zones, Andrew Bowen

Electronic Theses and Dissertations

The Plant Hardiness Zone Map consists of thirteen geographical zones that describe whether a plant can survive based on average annual minimal temperatures. As climate change progresses, minimum temperatures in all regions are expected to change. This work programmatically evaluates predicted future climate projection data and converts it to United States Department of Agriculture-defined hardiness zones. Through the next 80 years, hardiness zones are projected to move poleward; in effect, colder zones will lose area and warmer zones will gain area globally. Some implications include changes in crop growing degree days, which could alter crop productivity, migration and settlement of …


Non-Destructive Imaging Of Phytosulfokine Trafficking In Plants Using Fiber-Optic Fluorescence Microscopy, Bernard Abakah May 2023

Non-Destructive Imaging Of Phytosulfokine Trafficking In Plants Using Fiber-Optic Fluorescence Microscopy, Bernard Abakah

Electronic Theses and Dissertations

Plants secrete peptide ligands and use receptor signaling to respond to stress and control development. Understanding these phenomena is key to improving plant health and productivity for food, fiber, and energy applications. Phytosulfokine (PSK), a sulfated peptide hormone, regulates plant cell division, growth, and stress tolerance via specific phytosulfokine receptors (PSKRs). This study uses fiber-optic fluorescence microscopy to elucidate trafficking of PSK in live plants. The microscope features two-color optics and an objective lens connected to a 1-m coherent imaging fiber mounted on either a conventional upright microscope body or 5-axis positioning system (X–Y–Z plus pitch and yaw). PSK and …


Predicting High-Cap Tech Stock Polarity: A Combined Approach Using Support Vector Machines And Bidirectional Encoders From Transformers, Ian L. Grisham May 2023

Predicting High-Cap Tech Stock Polarity: A Combined Approach Using Support Vector Machines And Bidirectional Encoders From Transformers, Ian L. Grisham

Electronic Theses and Dissertations

The abundance, accessibility, and scale of data have engendered an era where machine learning can quickly and accurately solve complex problems, identify complicated patterns, and uncover intricate trends. One research area where many have applied these techniques is the stock market. Yet, financial domains are influenced by many factors and are notoriously difficult to predict due to their volatile and multivariate behavior. However, the literature indicates that public sentiment data may exhibit significant predictive qualities and improve a model’s ability to predict intricate trends. In this study, momentum SVM classification accuracy was compared between datasets that did and did not …


Identifying Taphonomic Distribution Patterns At The Gray Fossil Site, Shawn Haugrud May 2023

Identifying Taphonomic Distribution Patterns At The Gray Fossil Site, Shawn Haugrud

Electronic Theses and Dissertations

Since the early days of the discovery of the Gray Fossil Site (GFS), meticulous efforts to preserve the spatial data were a priority. Direct surveying of fossils prior to recovery, as well as grid mapping the site, provided relative spatial data within a square meter. Such efforts meant that even fragments and microfossils, recovered during the screening operations and eventual concentrate picking, maintained some spatial data. Available spatial data are used to identify smaller deposits within the greater system, as well as non-random distribution patterns among a number of GFS taxa. Patterns are particularly pronounced in the large-bodied taxa, Teleoceras …


Development Of Nonorthogonal Wavefunction Theories And Application To Multistate Reaction Processes., Emily Kempfer May 2023

Development Of Nonorthogonal Wavefunction Theories And Application To Multistate Reaction Processes., Emily Kempfer

Electronic Theses and Dissertations

Many prominent areas of technological development rely on exploiting the photochemical response of molecules. An application of particular interest is the control of molecular switches through a combination of different external stimuli. However, despite significant advances in theoretical approaches and numerous cases of successful application of theory, simulating photochemical reactions remains a computational challenge. Theoretical methods for describing excited states can be broadly divided into single-reference response methods and multireference methods. Single reference methods provide reliable semiquantitative results for single excitations. However, these methods cannot describe double-excited states, systems with strongly correlated ground states, or regions of degeneracy on the …


First Principles Study Of 2d Polar Heterostructures., Safia Abdullah R Alharbi May 2023

First Principles Study Of 2d Polar Heterostructures., Safia Abdullah R Alharbi

Electronic Theses and Dissertations

Recently, two-dimensional (2D) heterostructures have attracted extensive attention in nanomaterials science. They have been successfully fabricated and applied to nanotechnology in many fields, such as nanoelectronics, solar cells, sensors, energy stores, quantum information, etc. The most common heterostructures are 2D-lateral heterostructure (LH) and 2D-vertical heterostructure (VH) where each of them exhibits unique features depending on the direction of assembly, i.e., along in-plane or out-of-plane direction. Beyond the van der Waals-VH which possess of van der Waals (vdW) interaction, there are other types of heterostructures made of 2D polar materials that possess different types of chemical bonding nature, e.g., chemical bonds …