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Health Effects Of Oil Spills And Dispersal Of Oil Droplets And Zooplankton By Langmuir Cells, Sanjib Gurung

USF Tampa Graduate Theses and Dissertations

This Ph.D. dissertation deals with the study of the health effects of crude oil vapors from oil spills, the effect of Langmuir circulation on the dispersion of oil droplets during oil spill events, and the biological significance of Langmuir circulation. The introduction to areas of three major research projects undertaken during my Ph.D. is included in chapter 1 and the relevant literature review is included in chapter 2. The first research project described in chapter 3 involves the quantification of health effects on embryonic Gulf killifish due to exposure to crude oil vapors. The second research project described in chapter …

Magnetism In Doped And Hybrid Two – Dimensional Transition Metal Dichalcogenides, Nalaka Kapuruge

USF Tampa Graduate Theses and Dissertations

In recent years, spintronics has gained increasing interest due to the possibility of storing and processing information through the manipulation of both the charge and spin of an electron. Dilute magnetic semiconductors are ideal for the fabrication of such devices as they display carrier-mediated ferromagnetism which allows the electronic control of magnetism. Transferring these properties into the two-dimensional (2D) realm is very attractive for both fundamental research and novel applications. The recent discovery of long-range magnetic order in 2D materials has attracted a growing effort in the search for new functional 2D materials that can display ferromagnetic properties at room-temperature. …

Preventing Variadic Function Attacks Through Argument Width Counting, Brennan Ward

USF Tampa Graduate Theses and Dissertations

Format String attacks, first noted in June 2000 [1], are a type of attack in which anadversary has control of the string argument (the format string) passed to a string format function (such as printf). Such control allows the attacker to read and write arbitrary program memory. To prevent these attacks, various methodologies have been proposed, each with their own costs and benefits. I present a novel solution to this problem through argument width counting, ensuring that such format functions cannot access stack memory beyond the space where arguments were placed. Additionally, I show how this approach can be expanded …

A Study Of Deep Learning Silhouette Extractors For Gait Recognition, Sneha Oladhri

USF Tampa Graduate Theses and Dissertations

Gait recognition has gained importance in biometrics for identifying a person. It is performed by analyzing the gait features extracted from a video of a walking person. Gait features can be represented using silhouettes, pose elements, 3d human body features, or the combination of any of the above features. Most gait recognition algorithms use silhouette data for modeling. Therefore the quality of the silhouettes is crucial for achieving better recognition results. Many previous works have used the silhouettes given with the dataset for developing a gait model. In this work, we will test the performance of different background subtraction algorithms …

Coarse-Grained Modeling Studies Of Entangled Semiflexible Polymers: Melts, Glasses, And Granular Media, Joseph Fox D. Dietz

USF Tampa Graduate Theses and Dissertations

This dissertation is devoted to the computational study of model semiflexible polymers using a coarse-grained bead-spring approach and molecular dynamics (MD) simulations. Much of the work presented here is motivated by the need to derive predictive models for describing polymeric materials’ macroscopic mechanical response from the underlying local structure or local chain parameters. This dissertation describes polymeric materials in the context of granular media, melts, and glasses with a focus on relating characteristics such as chain stiffness and local structure to systems’ solidification, rheology, and fracture mechanisms.

Chain stiffness κ and structural properties like chains’ characteristic bond angle θ0 are …

Assessment And Prevention Of Bacterial Regrowth In Stored Household Water In Eastern Coastal Madagascar, Lauren Judah

USF Tampa Graduate Theses and Dissertations

As of 2020, diarrheal diseases were the leading cause of death in Madagascar. A major cause of diarrheal illness is contaminated water, and one crucial aspect of preventing contaminated water is safe household storage. Bacterial regrowth between point-of-collection and household storage has been well established in literature. A frequently implicated source of regrowth is the storage container’s biofilm, which is a community of varying bacteria enclosed in a “slimy” extracellular polymeric substance that forms on surfaces in wet environments and anchors bacteria to those surfaces. The overall goal of this thesis was to quantify and control bacterial regrowth in household …

Ec Expression Of Activated K-Ras Leads To Capillary Deficiency Due To Excessive Lumen Formation, Reduced Pericyte Recruitment, And An Increased Susceptibility To Mmp-1-Dependent Vascular Regression, Zheying Sun

USF Tampa Graduate Theses and Dissertations

Activated k-Ras mutations play a role in a variety of pathological conditions, such as arteriovenous malformations (AVMs). To study the effect of activated k-Ras mutation on lumen formation, we engineered human ECs to simultaneously express the activated k-Ras (G12V) mutation and compared their ability to form lumens with control ECs. We demonstrated that ECs with k-RasV12 lead to marked stimulation of EC lumen formation due to dramatic increases in intracellular vacuole formation and fusion, signaling changes including accelerated Src kinase activation, and MT1-MMP-dependent lumen expansion, all of which drive the process of lumen formation. The markedly accentuated lumen formation is …

Identifying Significant Factors Affecting The Likelihood And Severity Level Of Shared E-Scooter Crashes, Recep Can Cakici

USF Tampa Graduate Theses and Dissertations

• Objective: To identify significant factors that affect the possibility of shared e-scooter related crashes in Tampa and St. Petersburg, FL, and also to capture determinants contributing to the level of injury of shared e-scooter related crashes in Tampa, FL.
• Background: Over the past few years, shared e-scooters have become a common form of micromobility; however, safety concerns have been raised due to the increased number of injury accidents involving e-scooters.
• Data and data sources: Survey questionnaires were designed to collect data from the general public on e-scooter sharing programs in Tampa and St. Petersburg, FL. The collected data include respondents’ …

Ambient Athleticism: Politicizing Akira’S Accelerationist Olympiad, Thomas G. Chaplin

USF Tampa Graduate Theses and Dissertations

This thesis politicizes Katsuhiro Otomo’s 1988 animated cyberpunk film, Akira, specifically through how it stages its myriad neoliberal crises as opportunities for accelerationist solutions mediated by the Tokyo Olympics. Akira’s display of fully animated and intense action physics produces an aesthetic relation to its own athletes that contracts around their bodies in an attempt to transgress classical and oppressive compositions. Akira’s vague utopic promise receives broad acceptance and affirmation by extant scholarship, often relying on the accelerative impulses found in the works of Gilles Deleuze to substantiate Akira’s hopeful ending. Invoking Gilles Deleuze’s notion of athleticism, this thesis critically rereads …

Measurement In Chemistry, Mathematics, And Physics Education: Student Explanations Of Organic Chemistry Reaction Mechanisms And Instructional Practices In Introductory Courses, Brandon J. Yik

USF Tampa Graduate Theses and Dissertations

The work in this dissertation is presented in two parts. The first part (Chapters 3 and 4) details work relating to students’ explanations of reaction mechanisms in organic chemistry. The second part (Chapters 5 and 6) details work relating to the evaluating the uptake of research-based instructional practices in introductory chemistry, mathematics, and physics courses.

To evaluate learning of organic chemistry reactions, instructors must ask students to construct written explanations of reaction mechanisms. Written assessments should focus on what is happening and why it is happening to promote deeper student understanding. However, for instructors to gain insight into students’ understanding, …

Accelerating Multiparametric Mri For Adaptive Radiotherapy, Shraddha Pandey

USF Tampa Graduate Theses and Dissertations

MR guided Radiotherapy (MRgRT) marks an important paradigm shift in the field of radiotherapy. Superior tissue contrast of MRI offers better visualization of the abnormal lesions, as a result precise radiation dose delivery is possible. In case of online treatment planning, MRgRT offers better control of intratumoral motion and quick adaptation to changes in the gross tumor volume. Nonetheless, the MRgRT process flow does suffer from some challenges that limit its clinical usability. The primary aspects of MRgRT workflow are MRI acquisition, tumor delineation, dose map prediction and administering treatment. It is estimated that the acquisition of MRI takes around …

Deceptive Appeals And Cognitive Influences Used In Fraudulent Scheme Sales Pitches, Rafael J. Toledo

USF Tampa Graduate Theses and Dissertations

Fraud schemes exploit the complex interplay that results from utilizing deceptive appeals to activate underlying cognitive influences. This study was designed, first, to identify the deceptive appeals present in the messaging of fraudulent schemes and, second, to identify the underlying cognitive influences being exploited by the deceptive appeals utilized. Findings reveal that effectively used deceptive appeals work to keep viewers’ mental processes in a state of cognitive ease. This state allows cognitive influences--such as heuristics, cognitive biases, and the System 1 mind--to remain in control of mental processing; however, System 1 is prone to accept deceptive beliefs. The results of …

Social Media Time Series Forecasting And User-Level Activity Prediction With Gradient Boosting, Deep Learning, And Data Augmentation, Fred Mubang

USF Tampa Graduate Theses and Dissertations

In the overall history of technological innovations, social media has only existed for a brief time, however its influence is undeniable. Researchers have found that it can be used to influence elections, spread health misinformation, and aid with financial pump-and-dump schemes. Keeping all this in mind, it is clear that more research is needed to predict the spread of information on social media in order to combat its malicious use.

To that end, in this dissertation, we explore the use of Machine Learning algorithms to perform time series forecasting and user-level activity prediction in social media. We address the different …

Adaptive Multi-Scale Place Cell Representations And Replay For Spatial Navigation And Learning In Autonomous Robots, Pablo Scleidorovich

USF Tampa Graduate Theses and Dissertations

Place cells are one of the most widely studied neurons thought to play a vital role in spatial cognition. Extensive studies show that their activity in the rodent hippocampus is highly correlated with the animal’s spatial location, forming “place fields” of smaller sizes near the dorsal pole and larger sizes near the ventral pole. Despite advances, it is yet unclear how this multi-scale representation enables navigation in complex environments.

In this dissertation, we analyze the place cell representation from a computational point of view, evaluating how multi-scale place fields impact navigation in large and cluttered environments. The objectives are to …

Towards High Performing And Reliable Deep Convolutional Neural Network Models For Typically Limited Medical Imaging Datasets, Kaoutar Ben Ahmed

USF Tampa Graduate Theses and Dissertations

Artificial Intelligence (AI) is “The science and engineering of making intelligent machines, especially intelligent computer programs”. Artificial Intelligence has been applied in a wide range of fields including automobiles, space, robotics, and healthcare.

According to recent reports, AI will have a huge impact on increasing the world economy by 2030 and it's expected that the greatest impact will be in the field of healthcare. The global market size of AI in healthcare was estimated at USD 10.4 billion in 2021 and is expected to grow at a high rate from 2022 to 2030 (CAGR of 38.4%). Applications of AI in …

Improving Wireless Networking From The Learning And Security Perspectives, Zhe Qu

USF Tampa Graduate Theses and Dissertations

Due to the high development of wireless networking and artificial intelligence, most of the data are generated from mobile devices, which distribute in different environments. As such, how to improve the performance of machine learning-based networking and its security should be carefully considered. To reduce the communication burden and protect private information from users, Federated Learning (FL) is a possible solution for learning-based wireless networking. Although FL achieves much success until now, it also remains some specific issues to be solved. In this dissertation, we propose two FL wireless networking frameworks and discuss two potential security issues.

In the FL …

A Residents’ Lens To Community Wellbeing, Sarah Combs

USF Tampa Graduate Theses and Dissertations

Despite its location just a few miles from the burgeoning University of South Florida, the University Area Community (UAC) is considered a severely economically disadvantaged neighborhood. When compared to its surrounding counties, the UAC experiences heightened unemployment and poverty rates in conjunction with a significantly lower median income and rate of homeownership. This study utilized a research method of Narrative Inquiry as told through Qualitative Research to gain a better understanding of the UAC residents’ lived experiences and of how community change agents could succeed in impacting community wellbeing in areas like affordable housing, resident employment, and resident engagement. The …

Advanced Methods For Railroad Station Operation Decisions: Data Analytics, Optimization, Automation, Yuan Wang

USF Tampa Graduate Theses and Dissertations

The continued and substantial growth in railroad transportation in many countries inspires railroad operators to leverage advanced methods into better railroad operation decisions. Among all facilities, significant returns on investment can always be achieved by optimizing the operations of network nodes - junctions and stations, because stations usually form the capacity bottlenecks in the system.

There are thousands of decision-making problems in relation to the station operations and can be classified into different levels to achieve different goals. From top to bottom, high-level business strategies aim to make decisions to achieve long-term strategical benefits, such as optimizing local station functionalities …

An Enterprise Risk Management Framework To Design Pro-Ethical Ai Solutions, Quintin P. Mcgrath

USF Tampa Graduate Theses and Dissertations

The effective use of Artificial Intelligence (AI) has immediate business benefits for an organization and its stakeholders through efficiency and quality gains, and the potential to explore and implement new business models. However, there are risks of unintended ethical consequences. Enterprise Risk Management (ERM) focuses on managing risk while maximizing business value from exploiting opportunities. Using applied ethics as a basis and the perspective that ethics includes both enabling human flourishing and not violating accepted norms, I argue that greater business value is achieved when an organization simultaneously targets the maximization of benefits and the minimization of harms for the …

Identification Of Secondary Structural Elements Contained Within The Intrinsically Disordered N-Terminal Tail Of The Bloom’S Syndrome Helicase., Vivek Somasundaram

USF Tampa Graduate Theses and Dissertations

The Bloom’s Syndrome Helicase (BLM) is one of five human RecQ helicases and is necessary for maintenance of genome stability. Whilst a crystal structure exists for the C-terminal domain of BLM, very limited structural knowledge is known about the intrinsically disordered N-terminal tail. This lack of insight exists, despite the fact that the N-terminus of BLM is essential for the overall biological activity of BLM. Here we provide an Nuclear Magnetic Resonance spectroscopy based approach that we used to identify two distinct ⍺-helices contained within the first 100 residues of BLM. In addition, we propose a mutagenesis-based approach involving rationally …

“Good War” On The Cool Medium: The Cold War's Influence On The Portrayal Of World War Ii On American Television, Michael A. Losasso

USF Tampa Graduate Theses and Dissertations

This dissertation is a cultural history of the Cold War’s influence on the portrayal of World War II on American television. In it, I chronicle the production, reception, and presentation of the war of three prominent American-produced documentary series from three periods of the Cold War – Victory at Sea (1952-1953), The Twentieth Century (1957-1966), and The Unknown War (1978). The dissertation posits that from the 1940s-1960s, the television portrayal of World War II was an embodiment of the values- that the United Sates was “fighting” for through a “triumphalist” narrative of a “just war” which recast the role of …

Advanced Analytical Method Development: From Highly-Enrolled Classroom To Data-Intensive Proteomics, Laxmi Sinduri Vuppala

USF Tampa Graduate Theses and Dissertations

In analytical chemistry, method development is key to identifying, separating, and quantifying chemical components of interest systems. The chemical aspects are fundamental to understanding the subject of any analytical system, whether in academic research, industry, or government. These methodologies serve as a bridge between the classroom, where students are taught to be curious and enlightened, and research, where one strives to contribute. The Ph.D. dissertation integrates advanced methodologies in basic and applied research and advanced instrumentation, but the core criteria for validation remain the same. As part of chemical education curriculum development, a large cohort of undergraduates performed two gas …

4d Printing Of Smart Hydrogel Scaffold To Program Neural Stem Cell Differentiation, Omar Khater

USF Tampa Graduate Theses and Dissertations

Injuries like Traumatic brain injuries (TBI) and Spinal cord injuries (CSI) areconsidered one of the biggest challenges in the medical sector as there is no specific treatment for these injuries and the medical intervention on these injuries is restricted to reducing the pain and removing the damaged human parts. One of the helpful and most effective treatment methods for these injuries involve neural tissue regeneration in the area of the injury. The main issue when trying to treat such injuries is that neural tissues are often unable to regenerate by themselves and require outer human intervention to differentiate. Biomedical scaffolds …

Elemental Sulfur And Metal Sulfide Minerals For Autotrophic Denitrification: Applications To Aquaculture, Groundwater Treatment, And Domestic Wastewater Treatment, Erica Amah Dasi

USF Tampa Graduate Theses and Dissertations

Nutrient pollution of waterways, from excess N and P, is a global concern that results in harmful impacts the environment, human health, and aquatic animals. This dissertation harnesses sulfur autotrophic denitrification to remove nutrients from groundwater, domestic wastewater, and wastewaters produced from marine recirculating aquaculture systems (RAS). Part 1 evaluates the denitrification performance of woodchips and elemental sulfur in cyclic denitrification filters (WS-CDFs) integrated into marine RAS operated under saline conditions. Part 2 investigates the use of metal sulfide minerals, with and without oyster shells, for supporting nutrient removal from groundwater in batch reactors. Part 3 assesses …

Healthcare Iot System And Network Design, Halil Ibrahim Deniz

USF Tampa Graduate Theses and Dissertations

The developing IoT concept offers many opportunities to service providers in the medical field. However, the functionality of the developed systems is increasing day by day, and it brings many different problems. One of the most important problems is the transmission of biomedical data of real-time monitoring systems to the medical server with the least delay. Network architectures are changing to meet the changing needs of densely connected devices, and “computing at the edge” is the new architectural approach emerging in IoT networks. This architecture is more dynamic than computation in the cloud because it enables data processing at each …

Advising Latinx Students For Postsecondary Career And Technical Education (Cte): A Qualitative Study Of High School Counselors In Florida, Adriana C. Magana

USF Tampa Graduate Theses and Dissertations

The purpose of this study was to gather detailed descriptions of information, resources, and interventions that school counselors use to inform and advise Latinx students of postsecondary CTE options. A qualitative study with semi-structured interviews was conducted to understand how Florida school counselors advise Latinx students for postsecondary Career and Technical Education (CTE) options. A three-prong conceptual framework was used, drawing from Bourdieu’s (1986) Theory of Cultural Capital, career development theories, and the American School Counselor Association’s (ASCA) National Model.

Ten school counselors working in public high schools in Florida participated in semi-structured interviews for this study. Altogether, the study’s …

Functional Morphology And Taphonomy Of Ordovician–Silurian Diploporan Echinoderms, Stephen Ashley Hill

USF Tampa Graduate Theses and Dissertations

Diploporan echinoderms were one of the most speciose groups of stemmed echinoderms during the Ordovician. Despite this widespread abundance, the fossil record of diploporan fauna consists primarily of incomplete specimens, with complete specimens being rare. While the theca, or body, is more commonly preserved, the feeding appendages and the attachment structures (i.e. stems or holdfasts) are seldomly preserved. Insight into these features is highly valuable to the understanding the paleoecology, like the feeding and respiratory strategies, of these enigmatic creatures.

One group of diploporan echinoderms which does have an extensive fossil record, is the Holocystites Fauna, primarily known from the …

Nano-Optical Imaging Of 2d Materials In The Quantum Regime, Hana Nazari Hrim

USF Tampa Graduate Theses and Dissertations

Chemical vapor deposition (CVD) growth of atomically thin 2D materials, such as transition metal dichalcogenides (TMDs), is a complex process that has not been completely understood. Large-scale growth of monolayer TMDs often leads to polycrystalline films with heterogeneous morphological and optical properties. Previous optical studies of 2D materials by far-field photoluminescence (PL) provided insights into CVD growth mechanisms of simple crystals, which were, however, limited in spatial resolution due to the diffraction limit. Here we performed correlated morphological and tip-enhanced PL (TEPL) imaging of CVD-grown polycrystalline monolayer molybdenum diselenide (MoSe2) flakes with heterogeneous optical response. We observed nanoscale spatial variations …

Deep Learning And Feature Engineering For Human Activity Recognition: Exploiting Novel Rich Learning Representations And Sub-Transfer Learning To Boost Practical Performance, Ria Kanjilal

USF Tampa Graduate Theses and Dissertations

A significant gap exists in our knowledge of how domain-specific feature extraction compares to unsupervised feature learning in the latent space of a deep neural network for a range of temporal applications including human activity recognition. This dissertation aims to address this gap specifically for human activity recognition using acceleration data. To ensure reproducibility, we use two publicly available datasets, UniMiB-SHAR and ExtraSensory, with a well-established history in the human activity recognition literature. We methodically analyze the performance of 64 different combinations of i) learning representations (in the form of raw temporal data or extracted features), ii) traditional and modern …

Stability And Interaction Analysis Of Inverter-Based Resources In Power Grids, Li Bao

USF Tampa Graduate Theses and Dissertations

The increasing penetration of inverter-based resources (IBRs) introduces some unexpected dynamic issues, including low-frequency oscillations. To investigate these phenomenon, a laboratory-scale grid-following voltage-source converter (VSC) system is implemented to demonstrate weak grid oscillations. Grid-following control is applied in VSC to provide active power, reactive power or ac voltage control. The test bed is also replicated in electromagnetic transient (EMT) simulation environment (MATLAB/SimPowerSystems) for benchmark purpose. Case studies are carried out to demonstrate low-frequency oscillations under real power/ac voltage or real power/reactive power control. An analytical model is carried out to examine the stability condition and compared with EMT or hardware …