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Understanding The Long-Term Patterns Of Change Of A Tidal Marsh In Mission Bay, San Diego, California, Carrie A. Shuster, Theresa Sinicrope Talley Ph.D., Drew Talley Ph.D., Zhi-Yong Yin Ph.D., Kellie Uyeda Ph.D.

Theses

Coastal marshes are among California’s most productive ecosystems and the most impacted, having been extensively modified by dredging, filling, and urban development. This thesis investigates over a century of change for a marsh in Northern Mission Bay, San Diego, California using ecological and spatial analyses.

Chapter 1 provides an overview of the environmental history and current land use of the Northern Mission Bay marsh, tracing changes from pre-contact Indigenous stewardship through colonial and modern urban development. It also introduces a restoration plant palette derived from historical and contemporary species occurrences, ecological functions, and documented cultural uses. By integrating ethnobotanical knowledge …

Enabling Asl Digital Communication Under Poor Internet Access, Swann Thantsin

Student Theses

Video conferencing degrades asymmetrically. When bandwidth falls, a hearing caller loses picture quality and keeps the conversation; a deaf and hard of hearing signer, whose language is carried entirely in the visual modality, loses the conversation. This thesis asks whether signed video reduced to the rates at which commercial platforms fail can be reconstructed at the receiver well enough to keep signing legible. A twostage reduction pipeline crops to the signer and transmits the face and hands at higher fidelity than their surroundings, achieving a reduction of approximately 99%; reconstruction uses a recurrent bottleneck mixer architecture, trained both conventionally and …

Adaptive Phishing Url Detection Using Hybrid Fuzzy C-Means Clustering And Xgboost, Muntadher Mohammed Kareem, Rawaa I. Farhan

Karbala International Journal of Modern Science

Phishing attacks continue to evolve in sophistication, rendering static detection methods increasingly ineffective. Existing URL-based approaches suffer from limited adaptability to emerging phishing patterns, mislabeled training data, and insufficient validation protocols. This paper proposes a hybrid phishing URL detection system that integrates Fuzzy C-Means (FCM) clustering with XGBoost classification, enhanced by a novel Micro Adaptive Feature Extractor (MAFE). The system employs a multi-stage pipeline: feature engineering generating 36 statistical and interaction features, MAFE producing 15 adaptive features through class-aware dynamic weighting, micro-pattern detection, and entropy analysis, and FCM with K=2 clusters providing soft membership features to XGBoost. A two-pass confidence-based …

Modeling And Simulation Of Solar Battery Charge Controller Using Adaptive Particle Swarm Optimization Mppt Algorithm, Mustafa Sacid Endiz, Göksel Gökkus

Mathematical Modelling and Numerical Simulation with Applications

Implementing an effective Maximum Power Point Tracking method is crucial for optimizing solar energy harvesting against environmental fluctuations like solar radiation and temperature. This paper introduces a novel approach for modeling and simulating a solar battery charge controller, using a modified Particle Swarm Optimization algorithm. The power stage of the system is based on a SEPIC converter, which is employed to manage the power conversion and improve the energy transfer to the battery. The developed circuit model is evaluated under various radiation levels at a constant temperature, as well as under different temperature levels at a constant radiation. Simulations are …

Development Of Minimalist Trifunctional Building Blocks For Chemical Biology Probe Synthesis, Luke E. Bohrer

Electronic Theses and Dissertations

The completion of the Human Genome Project in 2003 generated expectations that genomic information would accelerate the discovery of new protein drug targets and FDA-approved therapies. However, many small-molecule drug candidates continue to fail in clinical trials, and much of the human proteome remains undercharacterized in terms of structure, function, and disease relevance. Chemical tools are therefore essential for defining protein function, mapping protein interactions, and identifying disease-associated molecular mechanisms. Among these tools, small-molecule chemical probes provide a powerful strategy for connecting biological activity with target identification, functional analysis, and the development of effective therapies.

This dissertation describes the development …

Process From Noise: Erosion Threshold Variability And The Morphology Of Gravel-Bed Rivers, Robert Paul Kostynick

Arts & Sciences Graduate Student Theses and Dissertations

Rivers are remarkably consistent as their geometry, width, depth, and slope change systematically downstream in response to differences in fluid discharge and sediment transport throughout a channel. Rivers move both water and sediment through terrains that depend on these downstream geometric adjustments influencing water quality, ecology, infrastructure, channel morphology, and landscape evolution at increasing timescales respectively. Rivers thus influence all aspects of life and define our spatial landscapes that shape boundaries, whether physical, politically, or socially. Nevertheless, a river is dynamic and does not adhere to human-defined boundaries, making it vital that we understand how these features change over time …

Algebraic And Topological Methods In Computational Neuroscience, Trong-Thuc Trang

Electronic Theses and Dissertations

Neural data is incredibly rich in combinatorial, topological, and geometrical information, reflecting the intricate shape and connectivity of neural firing patterns. To decipher these structures, neuroscience increasingly relies on advanced mathematical tools to analyze neural activity. Here we study (1) neural codes within the poset P_Code of neural codes and (2) the connectivity of neural population activity within the insular cortex when responding to interoceptive information. In (1), we establish combinatorial constructions for all upward covering relations based on what we call “isolated subsets” with supporting theorems and give a slight modification of the existing downward covering relations. We …

Properties Of Enjoyable Mathematical Contexts From The Student Perspective, Emilie Nadine Hendrickson

Theses and Dissertations

Researchers continue to grapple with how to meaningfully engage students in mathematical content. Many students report disengagement due to perceptions that mathematics is difficult, irrelevant, boring, or anxiety-inducing. This study sought to understand how students interpret and respond to different mathematical problem contexts, with particular attention to the reasons students describe certain problems as enjoyable or unenjoyable. Using semi-structured interviews, this research examined student responses to a variety of mathematical problem types primarily across affective engagement. Students reflected on specific problem contexts and explained which features supported or hindered their enjoyment and engagement. Students described that contexts were enjoyable have …

Changes In Water Quality And Microbiota Over Two Years In Florida Hard Clam (Mercenaria Mercenaria) Hatcheries, Bonnie Getter

Electronic Theses and Dissertations

This thesis characterized the water quality and bacterial communities in nine hard clam hatcheries over two production years through weekly or biweekly water quality and chemistry monitoring, monthly bacterial plating in the second year of production, and select 16S microbiome sampling at select hatcheries to address production bottlenecks and support the reliable production of high-quality seed for Florida’s growing hard clam aquaculture industry. Logistic regression models showed that water source was distinguished by pH, salinity, alkalinity, and nitrite, whereas geographic location was distinguished by temperature, salinity, nitrate, and calcium; temperature, dissolved oxygen, salinity, and alkalinity distinguished seasons. Vibrio bacteria differed …

Temperature And Salinity Effects On The Physiology Of Bullfrog Tadpoles (Lithobates Catesbeianus) From A Suburban Temperate Wetland, Angela Brown

Theses, Dissertations and Culminating Projects

One of the most robust amphibians is the American Bullfrog, Lithobates catesbeianus, which is a widespread species that is invasive worldwide, and is broadly tolerant of a range of environmental conditions. Despite this tolerance, survival and performance of adult L. catesbeianus can be negatively affected by increasing temperatures and salinity resulting from anthropogenic impacts, such as climate change and road salts. This study focuses on the effects of acute salinity exposure (mimicking road salt influx into a pond) on L. catesbeianus tadpoles at different larval stages. Increased salinity was predicted to negatively affect two physiological performance measures. Critical maximum temperature …

A Social-Ecological Systems Approach To Integrating Outdoor Recreation And Black Bear Management: A Michigan Case Study, Megan Dorothy Stone

All Graduate Theses and Dissertations, Fall 2023 to Present

Outdoor recreation sits at the intersection of social and ecological systems, representing one of the primary ways in which humans directly interact with their natural environment. As a result, outdoor recreation management must balance providing high-quality outdoor recreation opportunities while simultaneously protecting natural resources in protected areas. Balancing these concurrent management goals has become more challenging in recent years as participation in outdoor recreation increases. This can lead to numerous negative impacts on the environment, such as wildlife disturbance. In this study, I explore the challenges and opportunities for collaboration between managers of outdoor recreation and black bears in the …

A Method For Assessing The Contribution Degree Of An Aviation Delivery System And Identifying Key Equipment, Xiaofeng Liu, Chengze Jiang, Xingyu Chen, Deyin Jiang, Bolin Shang, Bifeng Song

Journal of System Simulation

Abstract: Based on the delivery efficiency and delivery quality, a general aviation delivery system effectiveness evaluation model was constructed, and a calculation method of system contribution degree based on efficiency was given. By combining the system calculation experiment and simulation experiment based on agent-based modeling and simulation (ABMS), the design idea of the Monte Carlo simulation experiment for key equipment identification and equipment technology development trend analysis was sorted out, and the key equipment identification method based on ABMS and contribution evaluation was proposed. By taking the intercontinental long-range aviation delivery mission as an example, a variety of simulation experiments …

Viability Assessment Of Bovine Embryos: A Public Dataset And Deep Learning Baselines, Erfan Khayyati

All Graduate Theses and Dissertations, Fall 2023 to Present

Improving the success rates of cattle breeding is essential for sustainable agriculture, global food security, and high-quality livestock production. Currently, determining whether a lab-grown bovine embryo is healthy enough for a successful pregnancy requires highly trained experts to manually evaluate days of continuous time-lapse video footage. This process is not only incredibly time-consuming but also highly subjective; human reviewers often suffer from visual fatigue when tracking subtle, microscopic cellular changes over a seven-day period, leading to significant disagreement among even top experts on an embryo’s true potential. Furthermore, assessing bovine embryos is notoriously difficult due to their dark, lipid-dense cellular …

Investigation Of Yy Production Methods For Invasive Channel Catfish Ictalurus Punctatus Population Management, Andrew M. Wisniewski

All Graduate Theses and Dissertations, Fall 2023 to Present

Aquatic invasive species are one of the leading causes of native fish declines in the Southwestern United States. Channel Catfish Ictalurus punctatus were introduced into the Colorado River Basin, including the San Juan River, New Mexico, Colorado, and Utah for fishery enhancement during the 20th century. This introduction has contributed to the decline of native species and despite intensive mechanical removal efforts, the Channel Catfish population has persisted in the San Juan River. The Trojan Sex Chromosome approach is a promising eradication strategy that proposes the production and release of Trojan sex chromosome carriers (YY) to skew a targeted population’s …

A Data-Driven Nutrient Density Scoring Framework For Beef Using Principal Component Analysis, Teja Vuppala

All Graduate Theses and Dissertations, Fall 2023 to Present

Beef is one of the most nutrient-rich foods in the human diet, providing high-quality protein, iron, omega-3 fatty acids, B vitamins, and a wide range of other compounds important to health. However, current nutrition scoring systems used on food labels were designed to compare different foods to one another — for example, beef versus broccoli — and do not work well for judging the nutritional quality of different beef samples relative to each other. A grass-fed steak and a conventionally-finished steak can carry nearly identical Nutrition Facts panels while differing substantially in their content of omega-3 fatty acids, vitamins, and …

Land Condition Standards For The Western Australian Nullarbor Pastoral Region, Peter-Jon A. Waddell, Wayne J. Fletcher

Natural resources published reports

This report outlines the quantitative land condition standards that define acceptable pastoral land condition for the Western Australian part of the Nullarbor, to meet the regulatory requirements of the Land Administration Act 1997 and the Soil and Land Conservation Act 1945.

The Department of Primary Industries and Regional Development is developing regional-level pastoral land condition standards for Western Australia as a critical component of the Framework for sustainable pastoral management – revised edition (Fletcher 2022), the purpose of which is to address the Office of the Auditor General’s recommendations to improve the management of pastoral lands in WA …

Advantages Of Dynamic Representation For Related Rates Problems In Calculus, Eri Osuna

Electronic Theses, Projects, and Dissertations

Related-rates problems are a standard yet persistently difficult topic in first-semester calculus. Research increasingly recommends dynamic visualization tools such as GeoGebra, but direct comparisons of static and dynamic representations in related-rates settings remain scarce. This qualitative study examines how representation type shapes the quality of students' reasoning and their perceived experience during related-rates problem solving. Six mathematics students who had completed Calculus —a group of four undergraduates and a pair of graduate students—completed a static sliding-ladder task and a dynamic airplane-and-camera task supported by an interactive GeoGebra applet, followed by an interview. Findings indicate that the two representations supported reasoning …

A Large And Robust Legless Lizard (Squamata, Anguinae) From The Gray Fossil Site Of Eastern Tennessee, Justice D. Lamer

Electronic Theses and Dissertations

The early Pliocene Gray Fossil Site in Tennessee preserved an abundance of microfossils, including numerous anguid lizard specimens. This includes the following elements: dentaries, a pterygoid fragment, a jugal, frontals, parietal fragments, dorsal and caudal vertebrae, and many osteoderms. Because these specimens had not been placed taxonomically beyond the subfamily level, comparative anatomy of similar elements from extant anguids and some quantitative data were used to provide more refined identifications. Using these methods, it was determined that a new, robust type of Ophisaurus is represented at the Gray Fossil Site. Important novel features include relatively robust dentaries, fewer but broader …

Imaging Oxygen Near Implanted Medical Devices Through Tissue With X-Ray And Ultrasound Modulated Luminescence Chemical Imaging, Vigjna Abbaraju

All Dissertations

Oxygen plays a crucial role in stem cell maintenance, tissue regeneration, disease progression, and treatment efficacy. For example, understanding oxygen dynamics within implanted medical devices, such as bone scaffolds, is essential for successful tissue regeneration and can serve as an early indicator of infection. The existing oxygen sensing and imaging techniques are often limited by narrow imaging depth, low spatial resolution in vivo resulting in poor understanding of oxygen dynamics in tissue microenvironments. This dissertation describes the development of implantable sensors using X-ray scintillators and thermochromic leuco dye paired with phosphorescent oxygen dye (PtTFPP) to image oxygen using X-ray luminescent …

Can Kinematics Specify Tool Use Affordances?, Tyler Duffrin

All Dissertations

Object properties such as length, shape, and heaviness, as well as affordance-based properties such as strike-with-ability and poke-with-ability, can be perceived via dynamic touch as functions of inertia tensor invariants. The primary question addressed here was whether people can perceive these same power and precision properties for purely virtual objects, which lack dynamic physical forces. The Kinematic Specification of Dynamics (KSD) principle asserts that missing dynamics are lawfully specified by kinematic (visual) motion patterns, such that kinematic information alone may support successful interactions with virtual objects. In three experiments, we investigated (1) whether virtual reality (VR) users could calibrate to …

Evaluation Of Dredged Sediments As A Partial Replacement For Fine Aggregate In Mortar And Concrete, Ashish Gautam

Graduate Theses and Dissertations (2019 - present)

The feasibility of using dredged sediment from the Mobile River as a partial replacement for fine aggregate in mortar and concrete was investigated through a series of laboratory characterization and performance evaluation. Three dredged sediment samples (A, B and C) were initially examined, and Sample A was selected for further evaluation due to its closer resemblance to natural fine aggregate. This sample exhibited lower moisture content, higher sand equivalent values, higher specific gravity, and lower absorption. Mortar mixtures with 0, 10, 20, 30, 50, 75 and 100% dredged sediment replacement showed decreasing workability as the replacement level increased. The 20% …

Indigenous Community Research Opportunities, Sharon Hausam, Aaron M. Canter

Faculty Publications

This is a working paper produced as part of National Science Foundation project #2115169, “Transforming Rural-Urban Systems: Trajectories for Sustainability in the Intermountain West,” known as the “Intermountain West Transformation Network” (TN), led by the University of New Mexico with institutional partners at three additional universities in New Mexico, two in Arizona, and one each in Utah, Colorado, and Washington. The TN’s Indigenous and Tribal engagement was supported through a contract with Dr. Sharon Hausam, additional work by Aaron M. Canter, coordination with Dr. Lani Tsinnajinnie, and an Advisory Committee on Indigenous Information Needs primarily comprised of Indigenous representatives in …

Protecting Wetlands In Georgetown County, Sophia Harrison

Goal 6: Clean Water and Sanitation

No abstract provided.

Painting A Scene: 3d Painterly Rendering From Curves To Rebelle, William M. Luttrell

All Theses

Stylized 3D rendering has seen much development and success over the past few years. From Spider-Man: Across the Spider-Verse to The Bad Guys, many studios have developed tools to incorporate stylistic elements from graphic novels, comic books, watercolor paintings, and more into their productions. This stylization process incorporates the pacing, visual style, and themes from the source medium into the animated work, allowing a much greater freedom of expression for artists and directors.

Inspired by these films as well as the needs of the short film Kate Shelley and the Bridge of Darkness currently in production, This paper presents …

Integrating Hydrology And Human Water Footprints: A Case Study Of The Great Salt Lake Basin, Rachel Lynne Seeley

All Graduate Theses and Dissertations, Fall 2023 to Present

Global demand for water is outrunning supply, and how we account for water is part of the problem. Many water management frameworks are based solely on how much physical water moves through rivers, aquifers, and other water bodies, missing the water that is embedded in food and other products a region produces and exports. This study developed a new, generalizable water accounting framework that incorporates this “hidden water,” known as virtual water, into water management and applied the framework in the Great Salt Lake Basin.

The Great Salt Lake is shrinking, and an often-overlooked driver of the lake’s decline is …

Expression Levels Of Heat Shock Protein 72 And Their Correlation With Biomarkers Of Renal Function Among Hispanic Construction Workers Exposed To Ambient Heat In El Paso, Texas, Maria Fuentes

Open Access Theses & Dissertations

Heat shock proteins (HSP) are intracellular molecular proteins that are upregulated in response to cellular stress, including heat exposure. Through their protective functions, HSP help maintain protein structure, prevent protein denaturation, and preserve cellular homeostasis during states of physiological stress. Because of their cytoprotective properties, HSP have emerged as potential biomarkers for detecting early signs of tissue injury and predicting clinical outcomes associated with heat related illnesses (HRI), including acute kidney injuries (AKI). AKI is a leading cause of hospitalizations due to heat stress exposure and heat stroke. In the absence of early detection and effective therapeutic interventions, AKI may …

Environmental And Toxicological Assessments In The Fine Jewelry And Sapphire Industry: A Chemistry Approach, Maricarmen Lerma

Open Access Theses & Dissertations

This dissertation investigates the potential environmental and public health impacts associated with fine jewelry and the gemstone industry, specifically focusing on potentially toxic elements (PTEs) in sapphires. Heavy metal contamination within consumer goods and raw materials has become a pervasive issue in the United States. Potentially toxic elements (PTEs), such as lead (Pb), cadmium (Cd), and nickel (Ni), arsenic (As), pose significant toxic health risks. Human exposure to these PTEs via inhalation, ingestion, or dermal contact can induce severe health effects; Pb is associated with cognitive impairment and developmental delays in children, Cd exposure can cause pulmonary and renal damage …

Physically Based And Machine Learning-Driven Frameworks For Parallax Quantification, Artifact Detection, And Bias Diagnosis In Passive Microwave Precipitation Retrievals, Andres Felipe Monsalve Salazar

Open Access Theses & Dissertations

Passive microwave (PMW) radiometers are a primary source of global satellite precipitation estimates, but their retrievals are degraded by parallax-induced geolocation displacement, orbit-level artifacts, and environment-dependent biases. This dissertation develops physically based and machine learning-driven methods to assess the quality and increase the reliability of PMW precipitation retrievals, using the Global Precipitation Measurement (GPM) mission and its Goddard Profiling Algorithm (GPROF) as the primary testbed. It comprises three independent but complementary studies centered on the diagnosis of retrieval errors and the detection of observational artifacts. The first study introduces a physically based parallax correction that realigns cloud-level microwave signals with …

Advancing Electrochemical Strategies For Pfas Sensing And Degradation, Diego Camilo Puerto Diaz

Open Access Theses & Dissertations

Ensuring universal access to safe water is a critical global challenge, particularly due to pollution from contaminants of emerging concern such as per- and polyfluoroalkyl substances (PFAS). These synthetic fluorinated chemicals have been widely used since the late 1940s because of their chemical stability and hydrophobic/lipophobic properties. However, the toxicity and persistence of legacy PFAS, including PFOA and PFOS, led to their gradual phase-out and replacement by shorter-chain alternatives such as GenX and PFBS. These replacement PFAS remain less explored in terms of reliable detection and degradation strategies, despite increasing evidence of their environmental occurrence, mobility, and potential toxicity. The …

An Analysis Of Mating Strategies In Rotifers Inhabiting Temporary Habitats, Ariel Bollinger

Open Access Theses & Dissertations

Reproduction is critical for organisms inhabiting ephemeral aquatic habitats where desiccation risk favors rapid and successful mating. Monogonont rotifers rely on sexual reproduction to produce diapausing eggs that withstand harsh conditions. I investigated how mating behaviors vary among populations of five rotifer species based on the hydroperiod of their habitat: Epiphanes brachionus and E. chihuahuaensis were sampled from habitats with short (SH) and long (LH) hydroperiods; Euchlanis dilatata was collected from a short (SH) and a permanent habitat; and Plationus patulus and Sinantherina socialis were collected from a long (LH) and a permanent (Perm) habitat. I hypothesized that SH populations …