Digital Commons Network^™

Study Of The Ultrasonic Properties Of A Tissue-Mimicking Phantom Of Human Brain, Utsab Acharya

Electronic Theses and Dissertations

Preparing tissue-mimicking phantoms for brain ultrasound studies presents unique challenges due to the need to replicate the complex acoustic properties of cerebral tissue. Human brain tissue exhibits a speed of sound typically between 1520 and 1540 m/s, an attenuation coefficient ranging from 0.58 to 2.42 dB/cm in the 1–3 MHz frequency range, and a notably low backscatter coefficient between –94 and –82 dB/(cm・sr). Accurately reproducing these parameters simultaneously in a synthetic phantom is difficult because of the naturally low scattering properties of brain tissue and the interdependence of ultrasonic attenuation and scattering mechanisms. Polyvinyl alcohol (PVA) has emerged as a …

Data-Driven Modeling Of Levee Failure: A State-Of-The-Art Approach For Integrating Artificial Intelligence Techniques With Hydraulic Erosion And Geotechnical Characterization, Haitham O. Saleh

Electronic Theses and Dissertations

Flooding is one of the most destructive natural disasters in the United States, often resulting in catastrophic damage to communities and infrastructure. The primary flood-protection structures, earthen dams and levees, are critical for mitigating these impacts. In Mississippi alone, there are over 2,800 dams and 3,750 miles of levees along the Mississippi River and its tributaries. Of this, nearly 2,200 miles are along the mainstem Mississippi River, with the remaining levees situated along backwaters, tributaries, and floodways. Understanding the erosion behavior of these structures during overtopping events is essential for accurate failure prediction and risk assessment. This study focuses on …

Dream And Reality: Warping Southern Mythologies, Greta Koshenina

Electronic Theses and Dissertations

Details fade upon waking from dreams, and childhood memories wither over time. My work holds a moment and strips away details. What seems captured is ephemeral. This thesis explores the fleeting nature of memory through a multimedia installation of cyanotype photography and a poetic documentary short film. I blend family videos and photographs with ancient and medieval religious iconography to emphasize art's connection to the unconscious, particularly the archetypes expressed in dreams. The written portion examines the influence, process, and context of my artwork. I delve into these concepts in a review of Southern literature, documentary films, and photography. Oral …

Voltage-Dependent Anion-Selective Channels 1 And 2 Wild Type And Mutant Bh3-Like Domain Peptides: Analysis Of Secondary Structure And Binding Stoichiometry To Recombinant Bax, Geanell C. Adams

Electronic Theses and Dissertations

Despite national efforts to increase female participation in science, technology, engineering, and mathematics (STEM), women remain significantly underrepresented in collegiate STEM programs. This pilot study sought to identify pre-collegiate factors that influence female students’ decisions to enroll and persist in STEM collegiate programs at the University of Mississippi, a predominantly white R1 research institution using qualitative methods. Grounded in Bandura’s Social Learning Theory, the research examined the environmental, behavioral, and personal determinants that shape academic pathways for women in STEM.

Data were collected through semi-structured interviews with six sophomore female STEM majors. Thematic analysis revealed that early exposure to structured …

Underrepresented Medical Students: Perceptions Of Academic Persistence And Successful Completion Of Medical School, Nicholas Dakota Bibbs

Electronic Theses and Dissertations

Less than one percent of the United States population’s workforce are physicians. The road to becoming a medical doctor is long, complex, and taxing. Individuals desiring to become physicians must have large amounts of grit, persistence, patience, and a hard work ethic just to get to medical school. The students who are accepted into medical school come from various backgrounds with differing degrees of access to resources and opportunities to prepare them before and during their medical education. Studies show that students who are categorized as underrepresented in medicine often face the most challenges to achieving academic success. Understanding what …

Navigating Cultural Transitions: The Adaptation Experiences Of Bangladeshi International Students In The Usa, Khadiza Tul Kubra

Electronic Theses and Dissertations

This thesis explores how Bangladeshi international students adapt to life and study in the United States. I conducted in-depth interviews with students at the University of Mississippi to understand their everyday experiences. My focus was on how they manage cultural, academic, and social challenges. I used segmented assimilation theory, Berry’s acculturation model, and Bourdieu’s concept of cultural capital to guide my analysis. The findings are shared in three main parts. First, I discuss how students use community support and religious networks to feel at home. Second, I look at how they deal with language barriers, classroom culture, and identity shifts. …

Salinity Tolerance Of Bighead Carp And Its Implications For Dispersal In The Lake Pontchartrain Ecosystem, Alan Katzenmeyer

Electronic Theses and Dissertations

The introduction of invasive bighead carp (Hypophthalmichthys nobilis) into the Pearl and Pascagoula River systems via the Bonnet Carré Spillway during flood control operations poses a significant threat to these unique ecosystems. This dissertation's experiments investigated the role of salinity in limiting bighead carp dispersal, demonstrating that brackish waters do not necessarily restrict their range as previously assumed. While bighead carp exhibited no significant impairment in swimming performance in salinities at or below 5 ppt, acute and chronic exposure to salinities at 15 ppt proved lethal within 50 hours, representing a critical salinity threshold. Despite mortality at elevated salinities, the …

Storytelling In Context: How Resources Enable And Constrain The Stories Entrepreneurs Tell, John J. Rogers

Electronic Theses and Dissertations

This dissertation investigates how entrepreneurial storytelling is shaped by and shapes its material and cultural context, extending the Theory of Cultural Entrepreneurship (TOCE). While TOCE highlights storytelling as a mechanism through which entrepreneurs construct legitimacy and secure resources by drawing on culturally resonant narratives, prior research has largely overlooked the constraining and enabling role of material resources in this process. This dissertation addresses this gap by examining how context functions, not merely as a backdrop but as a constitutive force in entrepreneurial storytelling. Using ethnographic methods, two studies were conducted at a regenerative farm and processing facility in rural Mississippi. …

Quantification Of Auxin-Cytokinin Response During Primary Root And Lateral Root Development In Common Bean, Gurdeep Singh

Electronic Theses and Dissertations

Roots support water and nutrient uptake, anchorage, and soil interactions through continuous growth at the primary root tip (PRT). In common bean (Phaseolus vulgaris), new cells are produced in an open root apical meristem and subsequently elongate in the elongation zone, and together these processes drive root tip progression through the soil. Lateral roots (LRs) arise in the differentiation zone, where pairs of pericycle founder cells dedifferentiate, divide asymmetrically, and form lateral root primordia (LRP) that pass through defined developmental stages before emergence. Auxin and cytokinin (CK) are central regulators of both primary root growth and LR development, yet their …

Programming Carcass Composition Through Gestational Nutrition, Sydni Elise Borders

Electronic Theses and Dissertations

The objective of this study was to evaluate the influence of maternal nutrient restriction during mid-gestation on the performance of the dam, feeding performance, carcass composition, and genetic expression in the offspring. Cows (n = 46) were randomly assigned to one of two treatments based on global nutrient intake: 1) fed to achieve and/or maintain a BCS of 5 or 6 (Positive Energy Status [PES]; n = 24) or 2) fed to lose one BCS during 99 days of mid-gestation (Negative Energy Status [NES]; n = 22). Cows in NES had greater decreases (P < 0.05) in body fat stores and muscle mass, elevated NEFA concentrations, and displayed decreased (P < 0.05) DMI, HP, and GHG emissions. There were no differences in milk components or volume produced between treatments (P > 0.05). There were no differences in …

Impact Of Minimally Processed Red Meat On Biomarkers Of Cognitive Decline, Saba Vaezi

Electronic Theses and Dissertations

No abstract provided.

Evaluation Of High-Moisture Ear Corn As A Roughage Source In Finishing Diets Fed To Beef Steers, Riley J. Leeson

Electronic Theses and Dissertations

The objective of this study was to evaluate the feedlot performance, rumination activity, and carcass characteristics of high moisture ear corn (HMEC) as a roughage source in finishing diets fed to beef steers. Backgrounded steers (n = 191; initial shrunk weight [4% BW] = 449 kg  23.9 kg) were assigned randomly to 1 of 24 pens (8 steers/pen) with pens randomly assigned to one of four dietary treatments (6 pens/treatment): control diet with hay fed at 10% roughage equivalency (RE; HAY10), or HMEC at either 14% (EAR14), 10% (EAR10), or 6% (EAR6) RE. High-moisture ear corn was assumed to …

Finishing Location And Forage Diversity Influences Carcass Characteristics, Meat Quality Attributes, Terroir, And Color Stability Of Grass-Finished Bison Bulls, Garrett Tyler Weldy

Electronic Theses and Dissertations

The overall objective of this thesis is to determine the influence of finishing location and forage diversity on carcass characteristics, meat quality, terroir, and color stability of grass-finished bison bulls. The specific objectives were 1) Determine the effect of finishing location on carcass characteristics, meat quality attributes, and terroir of grass-finished bison bulls, 2) Investigate the effect of forage diversity on the carcass characteristics, meat quality attributes, and terroir of grass-finished bison bulls, and 3) Determine the effect of finishing location on the meat color stability of grass-finished bison bulls. Overall, results indicate that finishing location influenced carcass characteristics, objective …

The Influence Of Bottom-Up And Top-Down Effects On The Density And Distribution Of Common Leopards In The Eastern Himalayas, Karma Choki

Electronic Theses and Dissertations

Leopards (Panthera pardus fusca) are widely distributed across Asia, yet their conservation is overshadowed by the conservation status of other flagship predators like tigers (Panthera tigris), in the Eastern Himalayas. Despite their ability to coexist with other large carnivores, leopard populations are shaped by intricate ecological interactions and increasing human pressures. This thesis investigates the abundance and density, habitat use, and drivers of persistence of leopards across Bhutan to inform multi-species carnivore conservation planning. My first chapter provides an overview of the ecological roles of large carnivores and how they persist on the landscape. I review the mechanisms that facilitate …

Comparative Evaluation Of Fungal Strains For The Bioprocessing Of Soybean Hulls Using Cheese Whey As Fermentation Medium, Ruchita Bhattarai

Electronic Theses and Dissertations

Globally, soybean is the most widely cultivated oilseed crops, and serve as the primary source of cooking oil, contributing to around 50% of global oilseed production. During the industrial processing of soybean oil, a significant amount of soybean hull (SH) is produced, which makes up about 8% of the grain yield, resulting in approximately 18–20 million tons of hulls, one of the largest by-products in the soybean industry. The hulls have limited commercial value and are primarily used as fiber additives in dairy cattle feed, but a large portion is still discarded as agricultural waste. Similarly, cheese whey (CW), a …

Quantifying Landscape Variability Of Dynamic Soil Properties In The James River Valley, Eastern South Dakota, Sage Reuter-Schmitt

Electronic Theses and Dissertations

Dynamic soil properties (DSP) are a great tool for monitoring land-use change, and they are frequently used as soil health metrics. The NRCS and other soil researchers often use repeating, single-point or nested-point DSP studies to monitor and better understand the effects of land management decisions. While these studies capture the temporal variability of DSPs, they overlook the field-scale spatial variability of DSPs. Soil organic carbon (SOC) provides critical services to the ecosystem and other environments. These traits, as well as its susceptibility to management decisions, make SOC an important soil health indicator and DSP. Measuring SOC is often time …

Impacts Of Early/Mid-Gestation Shearing On Umbilical Blood Flow And Lamb Birth Weight, Mara Johnson

Electronic Theses and Dissertations

Studies outside the USA have reported that shearing pregnant ewes during mid to late gestation increases lamb birth weight. Our hypothesis was that shearing pregnant ewes on day 50 of gestation would increase umbilical blood flow (UBF), fetal size, lambing and placental weights. Twenty-eight Polypay ewes were randomly assigned to two treatments: shorn (S) and sham-shorn (Control, CON) and divided in singleton (S: n=4; CON: n=4), twins (S: n=5; CON: n=5) and triplets (S: n=5; CON: n=5). Umbilical BF and fetal and placental measurements were obtained via ultrasonography every 10 days from day 50 to 110 of gestation. Lamb birth …

Isolation And Characterization Of Rhizobia Bacteria From Midwest Soils, Jr Loya

Electronic Theses and Dissertations

Symbiotic bacteria, known as rhizobia, can colonize the roots of legume plants and then convert atmospheric nitrogen into a usable form by the host through the process called biological nitrogen fixation (BNF). Many of these bacteria produce other plant-growth-promoting benefits, such as nutrient acquisition, phytohormone production, and the modification of plant stress responses. Agricultural inoculants made from these bacteria have helped reduce the need for man-made nitrogenous fertilizers, known causes of pollution and eutrophication. There are additional benefits in developing bacteria inoculants local to regional soils. The ability to survive and compete in Midwest soil and climates present an opportunity …

Deep Learning For Computer Vision Applications In Medical Diagnostics And Wildlife Monitoring, Mostapha Al Saidi

Electronic Theses and Dissertations

This dissertation explores innovative applications of deep learning and computer vision techniques across three distinct domains: medical imaging, dermatological diagnostics, and wildlife monitoring. The research addresses critical challenges in each field through the development and optimization of convolutional neural networks and other deep learning architectures.

The first study examines COVID-19 classification from X-ray images, comparing one-shot versus two-stage classification approaches using transfer learning with pre-trained models such as VGG16 and VGG19. The initial hypothesis was that breaking down the classification task into two optimized tasks would yield better results than one-shot classification. Results demonstrated that the single-stage approach achieved superior …

“Thank You For Hearing Me”: Listening To Stories Of Linguicism, Caroline Asher Webb

Electronic Theses and Dissertations

This dissertation examines the effects of linguicism on nonnative speakers of English who are currently studying in higher education in the United States or other English-dominant countries. Linguicism, also called linguistic discrimination, others and discriminates against people based on their oral or written language use. Rooted in master narratives of Standard English, monolingualism, and the native speaker, linguicism, unlike other forms of discrimination, such as gender or racial discrimination, is subtle and unmarked, thus permeating the consciousness of even the most well-intentioned of people.

Using a Critical Race Theory framework, the present study utilized a storytelling methodology to gather first-hand …

Assessing Trophic Pathways In The Southern Indian River Lagoon Using Fatty Acid Markers, Joedeelee Rigdon

Electronic Theses and Dissertations

The Indian River Lagoon (IRL) comprises over 200 Km of the Florida’s east coast and is a bar-built estuary making up one of the most biodiverse estuarine environments in North America. Toxins produced by increasingly frequent harmful algae blooms in the IRL are found throughout the food web, from zooplankton to fish, to apex predators. The impact of species characterized as harmful algae can be traced using fatty acid markers, as phytoplankton and algae that make up HABs produce characteristic poly-unsaturated fatty acids (PUFA), which have conservative ratios between trophic levels. This study measured the fatty acid composition of two …

Here, There: Jewish Identities In The South Through The Lens Of Food, Charles George Pappas

Electronic Theses and Dissertations

This thesis examines the role that place performs in the creation of different Jewish identities in the South through the study of foodways practices. The first chapter provides a historical background of Jewish foodways and an analysis of two Jewish cookbooks and their recipes. These texts act as historical markers of the similarities and differences between varying diasporas across space and time and show how these elements impact Jewish culinary practices. Chapter two is centered around an oral history conducted with Jewish chef Laurence Faber and the places that have shaped his approach to the food served at his Knoxville …

The Meta-Portal Fantasy, Alex Lawrynas

Electronic Theses and Dissertations

The genre of Portal Fantasy seeks to bridge the gap between the primary world and the secondary, its characters often upended from their normal everyday lives in favor of the fantastic. I will be focusing on the genre and the effects of its complexity on its characters. For this I will be looking into the ways in which the portal fantasy is constructed, beginning with a brief introduction of the genre, and moving on to dissecting the ways in which the concept of the portal is navigated, the change and or loss of self that occurs, and finally how the …

Sleep Quality, Volumetric Brain Biomarkers For Ad, Executive Function, & Cognitive Decline In Older Adults, Layaly Shihadeh

Electronic Theses and Dissertations

Objective: Our aims were to examine differences in sleep quality sub scores and total scores across diagnostic groups cross-sectionally and longitudinally, correlate executive function scores and volumetric biomarkers of AD (prefrontal cortical and hippocampal volumes) with sleep quality scores, and explore how demographic variables may serve to moderate how sleep quality effects diagnosis. Method: 381 participants were classified into 3 diagnostic groups (Cognitively normal (CN), mild cognitive impairment (MCI), and dementia) based on the CDR global score. Prefrontal cortical volume, hippocampal volume, and PSQI total and sub scores were used as predictors of progression status. Daytime dysfunction, sleep duration, and …

Population Genetics Of Shallow And Mesophotic Corals And Sponges In The Gulf Of Mexico And Florida, Ryan J. Eckert

Electronic Theses and Dissertations

Population genetic analyses provide critical insights into biodiversity and resilience on coral reefs. This dissertation investigated the genetic connectivity and cryptic diversity of multiple foundational reef species, the corals Stephanocoenia intersepta, Orbicella faveolata, Montastraea cavernosa, and the sponge Xestospongia muta, across shallow and mesophotic reefs in the Flower Garden Banks National Marine Sanctuary (FGBNMS) and across marine protected areas on the Florida Reef Tract. Using a reduced representation genotyping approach, 2bRAD-seq, we generated genome-wide single nucleotide polymorphism (SNP) datasets for each species to assess patterns of population structure across regions and depth zones. Analyses uncovered cryptic lineages …

Mapless Autonomous Navigation Using Monocular Vision, Sai Digvijay Neelam

Electronic Theses and Dissertations

This thesis investigates monocular vision-based navigation for autonomous ground robots in indoor environments. It explores the effectiveness of mapless navigation strategies using image inputs and evaluates both modular and end-to-end deep learning techniques. A comprehensive implementation pipeline was developed on a Clearpath Dingo robot, comparing the approaches: classical optical flow (Farneback), modular deep learning with motion planning, and an end-to-end model.

The modular methods involve predicting region-wise obstacle depths using a ResNet 18 based model trained on a custom indoor dataset, followed by a motion planner. The end-to-end approach leverages a ResNet-18 architecture to jointly predict steering angles and collision …

Modeling Single-Engine Failure In Dual-Engine Tilt-Rotor Aircraft, Alexander Christopher Gaudreau

Electronic Theses and Dissertations

While single-engine failure has been considered in dual-engine tilt-rotor aircraft, more complex failures have been less investigated. This thesis will model a simultaneous powertrain and drivetrain complex failure scenario during vertical flight on a dual-engine tilt-rotor aircraft. This thesis is valuable to designers and operators, as it will simulate the aircraft's complex failure scenario and flight dynamics. Complex failure is modeled using MATLAB’s Simulink to accomplish a six degrees-of-freedom translational and rotational dynamic and kinematic free-fall model. A counter-rotating rotor system representation for the dual-engine tilt-rotor aircraft was also achieved by incorporating the rotor block in Simulink. It was discovered …

Spot (Smart Position And Temperature) Tagging Reveals Environmental Factors That Shape Blacktip Shark (Carcharhinus Limbatus) Annual Migrations., Isaac Tuszynski

Electronic Theses and Dissertations

Blacktip sharks (Carcharhinus limbatus) in the Western Atlantic migrate annually to spend the winter in waters off the coast of southeastern Florida. In the spring, these sharks migrate north to waters ranging as far north as Long Island, New York. This study was based on spatial data collected by SPOT (Smart Position and Temperature) tags deployed on blacktip sharks from 2017 to 2024. The data from the tags were used to investigate the offshore extent of the migration, the thermal preferences of these sharks, and which environmental variables can be used to predict their latitudinal distribution. Most blacktip detections were …

The Effect Of Huntington’S Disease On The Mechanical And Electrical Properties Of Red Blood Cells, Liliana Ponkratova

Electronic Theses and Dissertations

Huntington’s disease (HD) has an impact on brain tissues and can alter the biochemical properties of the peripheral blood. Evidence in existing literature suggests that peripheral mutant Huntingtin protein may be involved and deteriorate HD. Red blood cells (RBCs), being the most abundant type of cells in the peripheral blood, can show detectable changes in their biophysical properties due to subtle changes in cell membranes. These changes can offer a minimally invasive means to track the progression of the disease. The transgenic line R6/2 is used as the disease model. Utilizing the electro-deformation spectroscopy, we measured membrane permittivity, cytoplasm conductivity, …

Transcriptional Regulation Of Mouse Line-1 Subfamilies, Karabi Saha

Electronic Theses and Dissertations

No abstract provided.