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Statistical Approaches In Evolutionary Biology: Using Threespine Stickleback Fish To Test Fisher's Geometric Model And Evaluate Methods For Handling Missing Data, Aaron Mathew Myrold Jan 2025

Statistical Approaches In Evolutionary Biology: Using Threespine Stickleback Fish To Test Fisher's Geometric Model And Evaluate Methods For Handling Missing Data, Aaron Mathew Myrold

Dissertations

This thesis explores two distinct yet complementary aspects of evolutionary biology. The first chapter tests predictions from Fisher's geometric model of adaptation using a finely resolved fossil sequence of Gasterosteus doryssus spanning approximately 21,250 years. I analyze phenotypic changes in three armor traits during adaptation to a new environment and find that while step sizes follow the predicted exponential distribution—with many small steps and few large ones—they do not adhere to the model's temporal prediction that large-effect mutations should fix early in the adaptive walk. This discrepancy likely reflects adaptation from standing genetic variation rather than de novo mutation. The …


Genetic Architecture Of Complex Traits In African Ancestries Across Diverse Environments, Isadore Gregga Jan 2025

Genetic Architecture Of Complex Traits In African Ancestries Across Diverse Environments, Isadore Gregga

Dissertations

Given genetic and environmental diversity, genetic prediction based on African- ancestries individuals in the US or UK may not transfer well to other African diaspora regions. The Modeling the Epidemiological Transition Study (METS) is a longitudinal study of cardiometabolic health in five African-ancestry populations. We performed genome-wide genotyping in METS participants from the US, Jamaica, South Africa, and Ghana. We aimed to explore how genetic models for the transcriptome and body mass index (BMI) built using US- based African-ancestries populations perform in these four diverse populations. A subset of METS participants also had whole blood RNA-Seq data. For these, we …


Characterizing Niche Specialization In Staphylococcus Epidermidis, Sandra Jablonsk Jan 2025

Characterizing Niche Specialization In Staphylococcus Epidermidis, Sandra Jablonsk

Dissertations

This thesis investigates the microbial diversity of Staphylococcus epidermidis (S. epidermidis) across various anatomical sites in the human body. While traditionally viewed as a benign skin microbe, S. epidermidis also inhabits the urinary, gastrointestinal, and respiratory tracts, raising questions about its genetic variation and adaptability in different environments. The research aims to compare strains of S. epidermidis isolated from the oral cavity, nostrils, urinary tract, and skin of healthy individuals to determine if they share a common ancestor or if they evolved independently in response to specific environmental factors. The study comprises three main aims. Aim 1 focuses on assessing …


Insights On The Cranial Anatomy And Osteohistology Of Cyonosaurus, Alexander Acker Jan 2025

Insights On The Cranial Anatomy And Osteohistology Of Cyonosaurus, Alexander Acker

Dissertations

This study investigates the cranial anatomy and life history of the small-bodied gorgonopsian Cyonosaurus. Previous research on gorgonopsians has disproportionately focused on larger members of the clade, leaving smaller forms relatively understudied. This gap has led to several unresolved questions, the most pressing of which concerns gorgonopsian ontogeny. Specifically, it remains unclear whether small-bodied gorgonopsians represent genuinely diminutive adult individuals or juveniles of larger species. The specimen NHCC LB1087 presents an ideal opportunity to address this issue and gain new insights into the biology of small-bodied gorgonopsians. The first chapter focuses on cranial anatomy. Due to the specimen’s preservation, many …


Examining Pyroptosis In Neutrophil-Like Differentiated Hl-60 Cells, Jared Long Jan 2025

Examining Pyroptosis In Neutrophil-Like Differentiated Hl-60 Cells, Jared Long

Dissertations

The innate immune system is the first line of defense against pathogens. Innate immune cells, such as macrophages and neutrophils, recognize pathogens through the recognition of pathogen associated molecular patterns or damage associated molecular patterns (PAMPS & DAMPS). When a pathogen is recognized, innate immune cells will start clearing the pathogen and secreting pro-inflammatory cytokines, such as interleukin-1β (IL-1β) to initiate the innate immune response. Release of IL-1β occurs through an unconventional secretory pathway triggered by inflammasome activation. Activation of the NLR family pyrin domain containing 3 (NLRP3) inflammasome cleaves both pro-IL-1β into mature IL-1β, and full length gasdermin-D (GSDMD) …


Interactions Between Microplastics, Biofilms, And Antimicrobials In Freshwater Streams, Ryan Thomas Krantz Jan 2025

Interactions Between Microplastics, Biofilms, And Antimicrobials In Freshwater Streams, Ryan Thomas Krantz

Dissertations

Microplastics (MPs) are ubiquitous contaminants in freshwater ecosystems that could be hotspots for the interaction of antimicrobial compounds and surface-attached microbial biofilm communities. MPs and antimicrobials are both common in wastewater and urban freshwaters and MPs can adsorb contaminants like antimicrobials to their surface. Within aquatic habitats, MPs also support colonization by microbial biofilms. Therefore, we hypothesized that the adsorption of antimicrobials to MP surfaces would affect microbial communities colonizing MPs, altering their diversity, composition, and antimicrobial resistance. We investigated the effects of these interactions across two studies. The first study, discussed in Chapter 2, used a microcosm approach to …


Leadership Communication And Symbolic Language In Organizational Change: A Study In Higher Education, Christine Fischer Jan 2025

Leadership Communication And Symbolic Language In Organizational Change: A Study In Higher Education, Christine Fischer

Dissertations

Higher education institutions face growing pressures related to affordability, accessibility, and trust. In this environment, leadership communication, especially symbolic language that frames transformation as mission-aligned, plays a central role in shaping organizational change. This qualitative single-case study examined how leaders at a private Christian liberal arts college used metaphors, narratives, and values-based discourse to communicate an innovative tuition model and how this language influenced stakeholder perceptions, engagement, and resistance. Data included 26 leadership communication documents, a metaphor-based faculty and staff survey, and eight semi-structured interviews. Reflexive thematic analysis and metaphorical analysis were used to interpret symbolic language, meaning-making processes, and …


Healthcare Providers’ Lived Experiences During Pivotal Change, Lisa Raynelle Shelley Jan 2025

Healthcare Providers’ Lived Experiences During Pivotal Change, Lisa Raynelle Shelley

Dissertations

This phenomenological study examined healthcare providers’ lived experiences of psychological safety and administrative leader behaviors that influenced those experiences during pivotal change. While much research addressed psychological safety among frontline healthcare staff, a gap was noticed concerning providers. This study aimed to investigate the impact of psychological safety and administrative support on provider engagement, emotional response, and retention during periods of significant change. Data were collected via a survey containing multiple-choice and open-ended questions, followed by semi-structured interviews. Four findings emerged. First, the providers’ pivotal events generated themes of “workplace power dynamics,” “systemic and organizational change,” “transformational crisis,” and “physical …


Directed Assembly Of Magnetic Binary Suspensions, David H. Harris Jan 2025

Directed Assembly Of Magnetic Binary Suspensions, David H. Harris

Dissertations

Colloids are particle suspensions in a continuous medium. The particle interactions promote the assembly of structures under the influence of a magnetic field, known as directed-assembly. The magnetic properties and shape anisotropy are relevant features of the particle building blocks to the assembled structures. The dipolar interaction between colloidal particles for directed assembly has been extensively modeled considering spherical particle potentials, which is inaccurate when anisotropic particles are at close range. This research aims to address the problem of quantifying the dipolar interaction between arbitrarily positioned and oriented ellipsoids with different aspect ratios and material properties. We combine the recently …


Correlating Optical Phase And Atmospheric Coherence Width In Characterizing Turbulence, Scott Alexander Kaiser Jan 2025

Correlating Optical Phase And Atmospheric Coherence Width In Characterizing Turbulence, Scott Alexander Kaiser

Dissertations

This dissertation presents the development, validation, and optimization of a novel Hartmann Turbulence Sensor (HTS) for real-time, high-speed characterization of atmospheric optical turbulence. The HTS captures and processes live data at 1 kHz and reports turbulence parameters at 22 Hz. A key innovation is the integration of a dominant spectral component selection method into the Difference in Differential Tilt Variance (DDTV) algorithm. By using spectral analysis to identify areas of interest (AOIs) based on their dominant spatial frequency content, this method reduces computational load by up to 75% while maintaining a low RMS error. It also offers a visual representation …


Signal-To-Interference Degradation Due To Adc Dynamic Range For A Pulsed Doppler Radar Digital Signal Processor, Shawn Richard German Jan 2025

Signal-To-Interference Degradation Due To Adc Dynamic Range For A Pulsed Doppler Radar Digital Signal Processor, Shawn Richard German

Dissertations

The objective of this study was to develop an expression for signal processor signal-to-interference ratio (SIR) improvement that combines factors that have historically been treated separately into a simple closed form expression, specifically factors such as analog-to-digital converter (ADC) dynamic range, phase noise, sub-quanta signal levels, signal-to-noise ratio (SNR), gain, automatic gain control (AGC), receiver noise, and signal and clutter characteristics. The SIR expression developed in this study quantifies how much a signal processor’s performance is degraded by the inclusion of an analog-to-digital converter (ADC) with respect to an equivalent well designed all-analog design. Using this unified SIR metric, expressions …


Toward Measurable Explainable Ethical Ai: An Llm-Driven Data Analytics Study, Greg Bacon Jan 2025

Toward Measurable Explainable Ethical Ai: An Llm-Driven Data Analytics Study, Greg Bacon

Dissertations

Large Language Models (LLMs) have been a hot area for popular and research audiences. Users marvel subjectively at Artificial Intelligence (AI) outputs — so much that OpenAI delayed public release of Generative Pre-trained Transformer 2 (GPT-2) back in 2019, citing ``safety and security concerns.'' This research advances ethical and transparent AI through qualitative and quantitative measures between user intent and LLM responses in a way that aims to assist users with clear indications of good and poor alignment and of where to backtrack to minimize bias and hallucinations. The use case is recommending grant topics in a United States Department …


Novel Ai/Ml-Based Frameworks For Protein Conformation Selection In Drug Discovery Applications, Shivangi Gupta Jan 2025

Novel Ai/Ml-Based Frameworks For Protein Conformation Selection In Drug Discovery Applications, Shivangi Gupta

Dissertations

Drug development is a lengthy, expensive process with a high failure rate. The urgency brought on by the COVID-19 pandemic has accelerated the integration of artificial intelligence (AI) and machine learning (ML) to enhance drug discovery by increasing target specificity, reducing toxicity, and optimizing formulation strategies. Building on this momentum, this dissertation introduces novel AI/ML-driven frameworks for protein conformation selection and classification, addressing critical challenges in modern drug discovery. However, designing such a novel AI/ML data-driven framework is a difficult task because most real-world biomedical datasets suffer from class imbalance issues, which can significantly skew AI/ML model training, resulting in …


Analysis Of Second-Order Decoupled Time-Stepping Schemes For The Navier-Stokes-Debye-Hückel Model Of Electroosmotic Flow, Craig S. Bosma Jan 2025

Analysis Of Second-Order Decoupled Time-Stepping Schemes For The Navier-Stokes-Debye-Hückel Model Of Electroosmotic Flow, Craig S. Bosma

Dissertations

Electroosmotic (EO) flow has attracted much attention in recent years due to applications in microfluidics, such as in lab-on-a-chip type systems. Because of the inherent difficulties in measuring and monitoring microfluidic channels, analysis of EO flow is often performed by numerical simulation. The Navier-Stokes-Debye-Hückel model — a simplification of the Nernst-Planck model which couples conservation of the ionic concentrations to the Navier-Stokes equations — is the preferred model for studying such flows when the zeta potential is small. In this work, we study the well-posedness of the unsteady Debye-Huckël model, and propose decoupled time-stepping schemes for numerical simulation. We demon- …


Manganism And The Development Of A Green Sustainable Low-Threshold Spectrophotometric Test For The Monitoring Of Manganese In Consumable Water, Anna Merritt Holmes Jan 2025

Manganism And The Development Of A Green Sustainable Low-Threshold Spectrophotometric Test For The Monitoring Of Manganese In Consumable Water, Anna Merritt Holmes

Dissertations

Manganism, a neurotoxic disease from the hyperaccumulation of manganese, follows an etiology that parallels Parkinsonism. Non-occupational Manganism is acquired by the lifelong accumulation of manganese through water contaminated by natural and industrial sources. Biologically active manganese (II) eludes flocculation and filtration removal methods at water utilities. The U.S. Standard Methods For the Examination of Water and Wastewater persulfate testing method uses mercury sulfate, concentrated nitric and phosphoric acids, silver nitrate, and ammonium persulfate. The low detection limit of 210 µg/L is an order of magnitude greater than the World Health Organization (WHO) allowable limit of 10-50 µg/L. In 2004, the …


Observational Analysis Of Small-Scale Structures Across The Earth’S Bow Shock, Rebecca Harvey Jan 2025

Observational Analysis Of Small-Scale Structures Across The Earth’S Bow Shock, Rebecca Harvey

Dissertations

This work identifies and characterizes magnetic structures in the solar wind and magnetosheath across the Earth’s bow shock. I investigate the differences between the properties of small-scale flux rope (SFR) structures immediately upstream and downstream of the bow shock by employing two data analysis methods: one based on wavelet transforms and the other based on the Grad-Shafranov (GS) detection and reconstruction techniques. 676 hours in the solar wind, and 1051 hours in the magnetosheath, of in situ magnetic field and plasma data from the Magnetospheric Multiscale (MMS) and Time History of Events and Macroscale Interactions during Substorms (THEMIS) missions were …


Online Chebyshev-Based Pseudospectral Methods For Nonlinear System Identification, Arian Yousefian Jan 2025

Online Chebyshev-Based Pseudospectral Methods For Nonlinear System Identification, Arian Yousefian

Dissertations

Nonlinear system identification plays a crucial role in developing effective control for various systems, including autonomous vehicles, robotics, and industrial process control. Acquiring the system model with minimal sensing and computation can significantly reduce control costs in these applications. Traditional adaptive control techniques often rely on uniform or high-frequency sampling, which may become impractical or computationally expensive for rapidly changing or high-dimensional systems. While Chebyshev-based pseudospectral (PS) methods have proven highly effective in offline contexts, their direct online implementation faces several challenges. Successfully approximating system dynamics online requires prior information about the approximation intervals to compute Chebyshev nodes for data …


Living In The Hyphen: Creating Puentes Through Encuentros And Pláticas With Latinx Cross-Cultural Kids, Jennifer Jane Daby Jan 2025

Living In The Hyphen: Creating Puentes Through Encuentros And Pláticas With Latinx Cross-Cultural Kids, Jennifer Jane Daby

Dissertations

Latinx cross-cultural kids, or children of immigrants, are often faced with a feeling of not belonging to mainstream American culture nor their parents’ home culture(s) of origin. As such, they are viewed through a deficit lens and forced to negotiate their sense of identity and belonging through language and culture to fit in. By embracing the concept of educación, using culturally responsive methods of encuentros and pláticas with cross-cultural kids and their families, this study intends to find ways to foster a sense of belonging for this population in schools through participants’ testimonies. It aims to find ways to bridge …


Assessing The Selection And Impact Of Completeness In Technical Measure Sets In Systems Engineering, Casey Eaton Jan 2025

Assessing The Selection And Impact Of Completeness In Technical Measure Sets In Systems Engineering, Casey Eaton

Dissertations

Technical measurement is foundational in large-scale complex engineered systems (LSCES) design and contract awards due to the state of practice of systems engineering. Although technical measurement is ubiquitous in systems engineering practice, the selection and assessment of the impact of a set of technical measures is often heuristics-based, rather than based on empirical evidence or theory. Current technical measure set selection has been observed to be subject to many challenges which, in turn, can degrade system outcomes. Two main thrusts comprise the research: selection and impact. Motivated by the potential impacts of a poor set of technical measures, a significant …


Existence And Stability Analysis For Non-Autonomous Systems Of Differential Equations In Multi-Dimensional Time, Michael Lott Jr. Jan 2025

Existence And Stability Analysis For Non-Autonomous Systems Of Differential Equations In Multi-Dimensional Time, Michael Lott Jr.

Dissertations

This dissertation studies the existence and stability of solutions for a class of non-autonomous systems of differential equations in multi-dimensional time, within the framework of Banach space. Focusing on both hyperbolic and parabolic cases, it presents a comprehensive range of results on existence and stability over finite and infinite time intervals. By leveraging the theory of evolution families, this work uncovers the conditions under which these systems have solutions and provides an in-depth analysis of how these solutions evolve, offering fresh perspectives on their dynamic behavior over time.


Synergizing Ground, Satellite And Numerical Weather Prediction Datasets To Derive Cloud Base Properties As Used In The Kain-Fritsch Convective Parameterization, David T. Haliczer Jan 2025

Synergizing Ground, Satellite And Numerical Weather Prediction Datasets To Derive Cloud Base Properties As Used In The Kain-Fritsch Convective Parameterization, David T. Haliczer

Dissertations

Cloud base height (CBH) and cloud base vertical velocity (CBVV) are essential parameters for understanding cloud formation, boundary layer evolution, and air exchange between the atmosphere and the boundary layer. CBH is linked to aviation safety and impacting the amount of solar radiation reaching the surface, while CBVV influences cloud development, condensation (droplet formation) and precipitation potential. High CBVV can erode capping inversions and trigger convection. These two parameters are the focus of this dissertation. CBH and maximum CBVV values were derived using a multi-linear regression equation (i.e., generalized linear models (GLM)) for CBH and a random forest model for …


Nonlinear Vortical Electron Acceleration In Magnetic Reconnection And Its Application To Solar Flares, Christopher Crawford Jan 2025

Nonlinear Vortical Electron Acceleration In Magnetic Reconnection And Its Application To Solar Flares, Christopher Crawford

Dissertations

The origin of solar energetic electrons has been a long-standing problem, namely the production of a huge number of energetic electrons with power-law energy spectra within a sufficiently short time. Using particle-in-cell (PIC) magnetic reconnection (MR) simulations based on a new vortical electron acceleration model proposed by Che and Zank (CZ) [21], I first investigated the scaling of the PIC MR simulations to the observational scales of solar flares. The CZ model reproduced the sharp two-stage transition observed in soft-hard-harder electron energy spectra, implying that the electron acceleration timescale must be a small fraction of the solar flare duration. Then …


F-Region Neutral Wind Responses To Magnetospheric Forcing In The Nightside Auroral Oval, Katherine Davidson Jan 2025

F-Region Neutral Wind Responses To Magnetospheric Forcing In The Nightside Auroral Oval, Katherine Davidson

Dissertations

High-latitude neutral winds have a number of drivers, both from solar and magnetospheric origins as well as from the lower atmosphere. The efficiency of the individual thermospheric forces, in addition to the relative strength of ion-neutral coupling, are not well characterized. Because of this, the neutral wind response to changes in ionospheric convection is not well understood, with response times ranging on the order of tens of minutes to hours. Using both data driven and modeling simulation efforts, we aim to develop a better understanding of high-latitude ionosphere-thermosphere coupling. In order to do this, three individual studies will be done …


Synthesis Of Poly (L-Glutamine) Of Controlled Chain Length : A Novel Synthetic Approach For Developing Models To Study Polyq Diseases, Nirupama Singh Jan 2025

Synthesis Of Poly (L-Glutamine) Of Controlled Chain Length : A Novel Synthetic Approach For Developing Models To Study Polyq Diseases, Nirupama Singh

Dissertations

The abnormal expansion of poly (L-glutamine) repeats beyond a normal threshold (with disease onset at >35 repeat units) has been linked with several neurodegenerative diseases classified as poly (Q) diseases. To investigate the role of this uncontrolled polyQ expansion in disease onset, it is important to understand the changes that occur when the length of poly (L-glutamine) sequences surpasses the normal threshold. To comprehend the role and behavior of these expanded segments, it is essential to develop synthetic techniques that allow polymer production with controlled length. This ensures the accurate representation of healthy and abnormal poly (L-glutamine) segments. However, a …


A Rubber-Band System For Dynamic Incentivization Of Parallelized Gamified Objectives, Nicholas Diliberti Jan 2025

A Rubber-Band System For Dynamic Incentivization Of Parallelized Gamified Objectives, Nicholas Diliberti

Dissertations

With the advent of videogames as the world's first mass-market interactive media, gamification has emerged as the premier way to harness powerful behavior-affecting gamified elements and place them in other contexts, such as education, fitness, and rehabilitation. This transposition, however, ignores a key tenant of user engagement: reward ought to be aligned with effort. Most, if not all, current gamification systems dispatch static reward allocations for their spread of gamified behaviors. In this paper, an alternative is presented: dynamic gamification. This dynamic gamification reads the user's current gamified state for indicators of aptitude, dynamically remaps rewards with a tuneable evaluation …


Understanding Pediatric Healthcare Access From A Black Parental Perspective : A Qualitative Study, Jessica A. Celestand Jan 2025

Understanding Pediatric Healthcare Access From A Black Parental Perspective : A Qualitative Study, Jessica A. Celestand

Dissertations

In the United States, healthcare access disparities have existed for several years in the African American/Black pediatric population. The District of Columbia ranks first nationally for health insurance coverage; however, African American/Black children have disproportionately experienced barriers to care compared to the District of Columbia’s pediatric population overall. There are current gaps in research that investigate African American/Black pediatric healthcare access from a parental perspective. The purpose of this descriptive phenomenology qualitative study was to explore research gaps by investigating barriers and facilitators to care, and the social determinants of health that impact pediatric healthcare access through the lens of …


Design And Synthesis Of Crosslinkable Amphiphilic Pegylated Poly(Amino Acid) Copolymers For Spion Encapsulation, Adekunle Titus Akinmola Jan 2025

Design And Synthesis Of Crosslinkable Amphiphilic Pegylated Poly(Amino Acid) Copolymers For Spion Encapsulation, Adekunle Titus Akinmola

Dissertations

The development of polymeric micelles for biomedical applications has been of significant interest due to their potential for targeted delivery for therapeutic and diagnostic agents. This dissertation focusses on the synthesis, characterization, and application of amphiphilic PEGylated poly(amino acid) block copolymers as nanocarriers for superparamagnetic iron oxide nanoparticles (SPIONs) in magnetic particle imaging (MPI). Series of novel diblock and triblock copolymers were synthesized through ring-opening polymerization of amino acid N-Carboxyanhydrides (NCAs) to afford HO-PEG77-b-p(L-Leu)m and HO-PEGx-b-p(Allyl-L-Gly)10-b-p(L-Leu)n. These polymers were further functionalized to yield their folate conjugates through dicyclohexylcarbodiimide (DCC) coupling. NMR and FTIR were used to verify the chemical structures …


Air-Breathing Hypersonic Missile Control Using Adaptive Higher Order Sliding Mode Control Driven By Finite- And Fixed-Time Sliding Mode Observers, Polk Yu Jan 2025

Air-Breathing Hypersonic Missile Control Using Adaptive Higher Order Sliding Mode Control Driven By Finite- And Fixed-Time Sliding Mode Observers, Polk Yu

Dissertations

This research is focused on the study of the trajectory tracking of a Hypersonic Missile (HM) in its terminal phase of flight in light of the cross coupling, high nonlinearity, and uncertainty in the missile dynamics. This is coupled with unmatched disturbances and perturbations that all need to be compensated for in a really short time. In this research, a relative degree approach is utilized to design an adaptive higher order sliding mode control (AHOSM) for controlling the nonlinear perturbed HM. This technique allows for the proposed observation/differentiation/control (autopilot) algorithms equipped with adaptation capabilities to be employed for designing the …


Multipoint Observations Of Energetic Particle Acceleration Associated With Corotating Interaction Regions, Ashok Silwal Jan 2025

Multipoint Observations Of Energetic Particle Acceleration Associated With Corotating Interaction Regions, Ashok Silwal

Dissertations

Stream Interaction Regions (SIRs) play a critical role in energetic particle acceleration and transport in the heliosphere. While shocks and compression regions associated with SIRs can accelerate particles to several MeV energies, most of our current understanding of these events is based on observations near 1 AU and beyond. Observations inside 1 AU, particularly by PSP and SolO, provide a unique opportunity to disentangle the roles of acceleration and transport. This dissertation presents the first detailed measurements of SIR-associated energetic particle events in the inner heliosphere between 0.15 and 0.80 AU using PSP, complemented by SolO and multi-spacecraft observations near …


Mutual Coupling Reduction Techniques In Transverse-Electric-Mode And Hybrid-Mode Microstrip Patch Antenna Arrays, Matthew A. Adams Jan 2025

Mutual Coupling Reduction Techniques In Transverse-Electric-Mode And Hybrid-Mode Microstrip Patch Antenna Arrays, Matthew A. Adams

Dissertations

When the elements of an antenna array are closely spaced, the electromagnetic coupling between them can distort the radiation patterns of the individual elements and change their input impedances, causing significant degradation in the array’s performance. Numerous mutual coupling reduction methods exist in the current literature, each of which allows array elements to be closely spaced while being well-isolated from each other. This dissertation investigates mutual coupling reduction techniques for microstrip patch antenna arrays utilizing elements that excite the fundamental transverse electric (TE) mode. First, a mutual coupling reduction method inspired by the TE-mode microstrip patch cavity model is proposed …