Physical Sciences and Mathematics Commons^™

Redox Control In A Fused Electron Transfer Flavoprotein From A Thermophilic Archaeon And Expanded Significance Of A Hydrogen Bond From A Conserved Histidine Residue That Contributes To Flavin Redox Tuning And Activation For Covalent Modification, Debarati Das

Theses and Dissertations--Chemistry

In absence of O₂ as terminal electron acceptors in anaerobic bacteria and archaea, carbohydrate metabolism is 15 times less efficient compared to aerobic energy metabolism resulting in energy deficit conditions. Despite their meager resources these anaerobes were able to generate H₂ and a chemiosmotic potential able to drive energy demanding reactions such as CO₂ or N₂ fixation. These observations raised concerns as production of high energy reductants (H₂) from mediocre fuels (NADH) defied the laws of thermodynamics.

In 2008, a known mechanism “electron bifurcation” but with flavins as redox mediators instead of quinones was …

Towards Automating The Study And Discovery Of Electroactive Π-Conjugated Molecules, Rebekah Ann Duke-Crockett

Theses and Dissertations--Chemistry

Chemistry is entering a new paradigm of automation and data-driven discovery. Automated discovery is grounded in well-curated “big data.” As generative and predictive models fueled by simulation data see growing success, emerging robotic automation enables the generation of unprecedented volumes of experimental data. Automation-powered, data-driven approaches hold tremendous potential for groundbreaking insights and innovations, particularly in the study and discovery of electroactive π-conjugated molecules. Realizing this potential, however, requires democratizing chemical data and the automation needed to generate and use it. There is a need to expand access to the tools for findable, accessible, interoperable, and reusable (FAIR) data management …

Design And Synthesis Of Novel Ligands For Bioorthogonal Catalysis, Asymmetric Synthesis, And Ferromagnetic Behavior, Alexander G. Olivelli

Theses and Dissertations--Chemistry

Small molecule metal complexes have diverse applications including usage as catalysts, single molecule magnets, photosensitizers and pharmaceuticals. The first research project in this work reports a new ligand which dimerizes upon coordination to afford a trinuclear Cu(I) complex. Due to the coordination geometry of the Cu(I) metal centers, paired with the strong nitrogen coordinating groups, the resulting complex is resistant to oxidation even in the presence of strong oxidants. The complex is shown to be efficient in the CuAAC reaction and used to tag anticancer drug candidates in vitro. The next project focuses on a series of amidine-based ligands featuring …

Machine Learning Models For Molecular-Based Functional Organic Materials, Moses Ogbaje

Theses and Dissertations--Chemistry

Organic semiconductors (OSC) are of interest for a wide range of flexible optoelectronics applications, including transistors, solar cells, and sensors, to name a few. Despite their promise, the design and optimization of OSC pose significant challenges due to the complexity of the structures of the molecular building blocks, varied packing configurations of these building blocks in the solid state, which impacts the optical and electronic response, and sensitivity of the solid-state packing to material processing conditions. Accurately predicting the solid-state properties of OSC traditionally requires high-level quantum mechanical methods. These methods, however, can be computationally demanding, particularly for large molecules …

Investigation Of D-Π-A Re (1) Complexes For The Homogenous Photocatalytic Reduction Of Co2, Ryan M. Chafin

Theses and Dissertations--Chemistry

Increasing anthropogenic emission of CO₂ into the atmosphere is a global issue that shows no signs of deceleration due to the current trends in dependencies on fossil fuels for energy demand. Although deleterious in nature, this greenhouse gas can serve as a useful feed-stock for the production of small-carbon-chain commercial chemicals if the factors owing to its inertness can be overcome. Fortuitously, CO₂’s chemically inert nature is already circumvented in nature through an elegant cascade of biochemical reactions known as photosynthesis, which nearly all plants and some families of bacteria exploit to produce simple sugars for metabolic …

Investigation Of Protein-Ligand Binding Interactions Through The Computational Methods Of Molecular Dynamics And Graph Neural Networks, Alexander Benjamin Wroe

Graduate Theses, Dissertations, and Problem Reports (ETD)

Studies in protein ligand binding are a significant focus in the field of medicinal chemistry

and biochemistry, facilitating a greater understanding of the structure-function relationship

of the protein and controlling function via drug development. In this research, we identify

new binding sites for lipids on the microbial membrane protein, proteorhodopsin, and apply

machine learning approaches to accelerate the generation of binding affinity-like data for the

use in the identification of potential small molecule drugs. The platelet activating factor

receptor. Cardiolipin, a lipid in membranes, and proteorhodopsin, a microbial proton pump,

are both commonly found in microbial membranes, but little is …

The Effect Of Facial Phenotypes On Differential Performance Of Facial Recognition, Evan R. Garrett

Graduate Theses, Dissertations, and Problem Reports (ETD)

Facial recognition technology is utilized in many facets of life. As the use has become more widespread these systems have improved in reliability and performance approaching the level of human accuracy. With these improvements the problem of bias still remains as a persistent problem. Efforts have been made to minimize the bias prevalent in the systems via studies into various demographic factors, creating training datasets that have a more uniform distribution of subjects, and other methods. As facial recognition is one of the most utilized forms of biometric recognition it is vital to analyze potential causes of bias to help …

Computational Approaches For Diagnosing Neurological Impairments And Restoring Functional Movement, Serhii Bahdasariants

Graduate Theses, Dissertations, and Problem Reports (ETD)

Movement is the primary means by which the nervous system converts intention into interaction with the environment. Voluntary limb motion enables standing, walking, reaching, and grasping—actions that underpin self‑care, communication, and economic participation. When diseases or injuries disrupt the pathways that couple neural commands to muscle forces—whether through cortical stroke, spinal cord injury, or peripheral nerve damage—mechanical outcomes such as weakness, loss of coordination, and ultimately reduced mobility emerge. These impairments cascade into secondary complications, increased dependence on caregivers, and diminished quality of life. Quantifying how the lesion alters the mechanics of movement is therefore essential for designing targeted interventions …

Expanding The Vibrating Sharp-Edge Spray Ionization Toolkit For Oligonucleotide Characterization, Sultan Mahmud

Graduate Theses, Dissertations, and Problem Reports (ETD)

A gentle or soft Ionization process is a critical component in native mass spectrometry (MS) to lift the biomolecules from the bulk solution into the gas phase environment of the mass spectrometer preserving their shape, topology and non-covalent interactions. Electrospray ionization (ESI) facilitates structural preservation of proteins, nucleic acids and their complexes and as a result it has been extensively used in native MS. However, in negative ion mode, ESI is somewhat limited in sensitivity due to corona discharge effect resulting from the requirement of a high amount of voltage. This often disrupts the ESI process and may not preserve …

Symp25s: Can Llm Detect Dementia?, Rishank Singh, Youxiang Zhu, Xiaohui Liang, John A. Batsis, Caroline Summerour

Paul English Applied Artificial Intelligence (AI) Institute Publications

High Cost of Traditional Screening: Formal cognitive assessments for dementia are resource-intensive and not easily accessible for large-scale screening. Speech-Based Alternatives: Existing speech-based methods (e.g., picture description, telephone interviews) aim to address this but have limitations. Lack of Natural Dialogue: These conventional approaches often use rigid, repetitive prompts and do not simulate real conversations. Engagement Issues: Repetition and lack of conversational depth can reduce engagement and affect the accuracy of responses over time. Untapped Potential of LLMs: Large language models (LLMs) are capable of generating natural, coherent, and adaptive dialogue. Research Gap: The application of LLMs for dementia detection through …

Symp25s: Cactas-Ai: Automatic Segmentaion Of Calcified Plaque In Carotid Arteries, Jiehyun Kim, Kevin Wang, Yu Sakai, Youxiang Zhu, Andrew C. Hu, Huy Q. Phi, Nathan Arnett, Grace J. Wang, Brett L. Cucchiara, Jae W. Song, Daniel Haehn

Paul English Applied Artificial Intelligence (AI) Institute Publications

Manual segmentation of calcified plaque, essential for assessing stroke risk, is time-consuming, and conventional methods like 2D and 3D UNet often struggle with the small size. We developed CACTAS-AI, a two-step segmentation process. This approach outperforms baseline methods in plaque segmentation.

Targeted Mitigation Strategies To Reduce Secondary Emissions In Co2 Capture Systems, Keemia Abad

Theses and Dissertations--Chemistry

Global CO₂ emissions from industrial, power generation and transportation sources has led to the call for increased implementation of carbon capture strategies. The most developed of these is point source carbon capture, which refers to the process of capturing CO₂ directly from large (point) source emitters, before the CO₂ is released into the atmosphere. The challenge becomes separating CO₂ from the other components of the emitted gas, mainly nitrogen. These CO₂ capture processes typically involve the use of aqueous solutions of amines to absorb (capture) CO₂ from the gas stream, where the CO₂ and the …

Exploring The Relationships Between Molecular Structure And Crystal Packing In Small-Molecule Organic Semiconductor Materials, Dean A. Windemuller

Theses and Dissertations--Chemistry

Organic semiconductor materials (OSCs) are rapidly becoming a vital part of the technological landscape. They possess unique properties that make them attractive for the electronics industry. Relatively low-temperature and low-cost processing are a large part of the promise of OSCs. Perhaps more importantly, organic materials can be modified in a relatively straightforward manner, presenting an opportunity for them to be tuned and adapted to a variety of purposes and applications. Polycyclic aromatic hydrocarbons (PAHs) form a large group within the field of OSC research. Some of the most promising high-performance materials in this category to-date are acenes and heteroacenes. This …

Effects Of A-Site Cation Structure And B-Site Metal On Optical And Electronic Properties Of 2d Ruddlesden-Popper Phase Tin-Based Hybrid Perovskites, Henry Pruett

Theses and Dissertations--Chemistry

Organic metal halide perovskites (HPs) are attractive materials for a variety of electronic applications due to their low cost, tunable band gaps, excellent charge transport properties, and high photoluminescence efficiency. As such, HPs are being investigated for use in solar cells, photodetectors, X-ray detectors, light emitting diodes, field effect transistors, lasers, resistive random-access memory, etc. Currently the most popular metal used in HPs is lead, but the use of lead comes with the potential for heavy metal exposure. Tin-based perovskites offer a less hazardous alternative, but their optoelectronic properties lag behind those of lead and less work has been done …

Limitations Of Scientific Articles And Navigated Future Directions With Llm And Rag, Ibrahim Al Azher

Graduate Research Theses & Dissertations

Traditional Topic Modeling approaches, as well as zero-shot, few-shot, and fine-tuned Large Language Models (LLMs), have struggled to generate topics alongside relevant text from diverse sources, particularly sections such as Limitations. This thesis investigates automated methods for analyzing and synthesizing key sections of scientific articles using LLMs, exploring multiple dimensions of scientific text analysis.

First, LimTopic is introduced as a method for extracting and modeling the limitations sections of research papers. By integrating LLM-based topic generation with BERTopic, the approach generates descriptive titles and concise summaries that highlight the boundaries and shortcomings of studies, ultimately guiding future research directions.

Second, …

Green's Functions And Fixed Points Of Quasiregular Maps, Mark Broderius

Graduate Research Theses & Dissertations

This dissertation is on the dynamics of planar quasiregular maps of degree 2. These maps have three parameters. One of these parameters determines the distortion, one of them determines the orientation, and the last one is a shift parameter. Our first objective is to construct a new dynamical version of Green's functions for these maps. These functions provide information about the escaping sets of our quasiregular maps and are used to prove topological results about them. We show that the boundary of the escaping set is either connected or consists of infinitely many components. Additionally, we prove that if one …

Effect Of Universal Health Coverage On Neonatal Mortality Rate In Sub-Saharan Africa: Addressing Missing Data In Health Indicators, Elizabeth Nalule Arihoona

Graduate Research Theses & Dissertations

This study utilizes two mixed-effects models to examine the effect of Universal Health Coverage on Neonatal Mortality Rate (NMR) in 30 countries of Sub-Saharan Africa from 2000-2019 while addressing the missing data in health indicators. Using natural cubic spline interpolation, I impute the missing values in the health coverage indices to preserve the location- specific trends of the data. Findings indicate that among the health Coverage indices, only Index1, which directly relates to coverage of maternal, newborn and child health services is significantly associated with reduced NMR. While higher Current Health Expenditure is associated with reduced NMR, a higher share …

X-Ray Standing-Wave Fluorescence Study Of The Interaction Of An Anti-Microbial Peptide With A Supported Phospholipid Bilayer, Gobind Basnet

Graduate Research Theses & Dissertations

To understand the mechanism by which anti-microbial peptide penetrates biological membranes,the study uses artificial supported lipid bilayers (SLBs) deposited on solid substrates. These bilayers were prepared from a lipid mixture of 1,2-dimyristoyl-sn-glycero-3- phosphocholine (DMPC)and 1,2-dimyristoyl-sn-glycero-3-phospho-(1’-rac-glycerol (DMPG) in a 10:1 molar ratio and were incubated both with and without indolicidin. Additionally, bilayers were studied after incubation with a labeled form of indolicidin, which involved attaching a 1.8 nm diameter gold nanoparticle to the peptide’s terminal arginine group.

X-ray reflectivity (XRR) was employed to identify structural differences between SLBsincubated with indolicidin and those without it. The introduction of gold labeling facilitated the …

Design, Synthesis, And Evaluation Of Di-Peptide Probes For Stoichiometric Quantitative Analysis Of Antibodies, Taylor Gladson

Graduate Research Theses & Dissertations

Quantitative information on biomarkers is a decisive factor in a wide range of situations concerning individual and public well-being. Under certain circumstances, the availability of accurate quantitative information can even become a matter of life or death. Therefore, the ability to make quantitative measurements in point-of-care (POC), do-it-yourself (DIY), and limited resource settings (LRS) is crucial for diagnostics, disease management, food safety, biomedical research, forensics, and other areas.In the work, we develop a POC/DIY/LRS-compatible platform for unambiguous (yes/no type) quantitative analysis of antibodies. The heart of the approach is negative cooperativity-based target – probe binding. The binding modality yields a …

Optimization Of Derivation Jobs And Modernization Of I/O Integration Tests For The Atlas Epxeriment, Arthur Charles Kraus

Graduate Research Theses & Dissertations

The High-Luminosity LHC (HL-LHC) is a phase of the LHC that is expected to start toward the end of the decade. With this comes an increase in data taken per year that current software and computing infrastructure, including I/O, is being prepared to handle. The ATLAS experiment's Software Performance Optimization Team has areas in development to improve the Athena software framework that is scalable in performance and ready for wide-spread HL-LHC era data taking. One area of interest is optimization of derivation production jobs by improving derived object data stored to disk by about 4-5% by eliminating the upper-limit on …

Leveraging Synthetic Data For Efficient Training Of Ai Models For Real-World Object Detection, Reinaldo A. Moraga

Graduate Research Theses & Dissertations

Modern computer vision (CV) systems largely depend on real-world data for training, which is costly in terms of time, materials, and resources. As industries push toward automation and Artificial Intelligence (AI) -driven solutions, the need for enabling more efficient model training is growing. The primary aim of this work is to explore a framework tailored for industrial applications that uses synthetic images generated from 3D models to train a CV model capable of real-world object detection. This approach seeks to reduce the time, cost, and resources typically required for training AI models with real-world data. This work presents a method …

Geology, Paleoecology And Vertebrate Biostratigraphy Of The Hell Creek Formation, Carter County, Montana, Usa, Joshua Collin Mathews

Graduate Research Theses & Dissertations

The Hell Creek Formation of the Northern Great Plains records one of the greatest mass extinction events in Earth’s history, bringing to a close the reign of the dinosaurs at the end of the Cretaceous period. This rock unit comprises one of the most studied geological formations in the world and is one of the few locations on the planet that preserve terrestrial deposits containing ejecta from the bolide impact that slammed into the Yucatan Peninsula 66 million years ago. This profound event in the geologic record has led to numerous studies of paleobiotas, climate change, ecosystem recovery dynamics, and …

Facial Reduction Of Semidefinite Relaxations Of Binary Quadratic Problems, Ian Sugrue

Graduate Research Theses & Dissertations

A standard technique for bounding a combinatorial optimization problem is to form a semidefinite relaxation of the problem by "lifting" the problem into a higher dimensional space of symmetric matrices. For some combinatorial problems such as maximum k-cluster, the resulting semidefinite relaxation is not strictly feasible. In the context of the maximum k-cluster problem, we present an equivalent, strictly feasible semidefinite relaxation by way of the dimensionality reduction technique known as facial reduction. We provide a recipe to form this semidefinite relaxation directly, bypassing the lifting and facial reduction steps entirely. We then present our work on generalizing this result, …

Convective Modes Associated With Precipitation Exceeding Postfire Debris Flow Thresholds In The Southwestern United States, Anya M. Aponte Torres

Graduate Research Theses & Dissertations

Postfire debris flows can occur when surface-water runoff dislodges and carries a slurry of loose sediment and vegetation downslope, usually in steep, recently burned terrain. Short-duration, high-intensity rainfall embedded within short or long-duration rainstorms (e.g., thunderstorms and atmospheric rivers) is most commonly associated with this mode of debris-flow initiation. The typical horizontal grid spacings of global numerical weather prediction and general circulation models are too coarse to resolve these convective precipitation features, which poses an obstacle to short-term forecasting and investigating future trends in the frequency, magnitude, and characteristics of debris-flow generating rainfall. For this study, 15-minute precipitation and simulated …

Unlocking The Secrets Of High-Frequency Financial Data: Innovative Approaches To Modeling And Analysis, Lu Zhang

Graduate Research Theses & Dissertations

High-frequency trading (HFT) has emerged as a pivotal innovation in modern financial markets, characterized by rapid, data-driven decision-making processes that capitalize on granular, time-stamped market data. This dissertation examines the predictability of intraday stock price movements during the final 30 minutes of U.S. trading, employing a Bayesian regression model with Student-t error terms to address the limitations of traditional Gaussian-based methods. The analysis reveals a decline in established predictors and the emergence of new dynamics, such as post-Federal Reserve "tug-of-war" effects. The research further advances high-frequency financial modeling by introducing a comprehensive data engineering pipeline and applying cutting-edge deep learning …

Monte Carlo Modeling Of Spin Polarized Photoemission From Gaas At Low Temperatures And Positive Electron Affinity Surfaces, John Rison Callahan

Graduate Research Theses & Dissertations

Research and development of new photocathode materials are essential to the continuing success and productivity of accelerator technology. High-quality photocathodes characterized by high quantum efficiencies, long lifetimes, low mean transverse energies, and robustness to vacuum environments and operation loads are becoming increasingly essential to the successful operation of the next generation of high brightness accelerator applications. For nuclear and high-energy physics experiments and other applications that rely on spin-polarized electron beams, photocathodes must also demonstrate high electron spin polarizations. The development of state of-the-art spin-polarized photocathodes will require both development of methods to improve the quality of already existing cathode …

Point Of Care (Poc) - Compatible Detection Platform Based On Catalase Activity Of Dna G-Quadruplexes, Elzbieta Iwaniuk

Graduate Research Theses & Dissertations

The goal of our project is to develop an equipment-free signal readout platform suitable for potential molecular diagnostics applications. In the development, we adhere to (RE)ASSURED (Real time, Ease of specimen collection, Affordable, Sensitive, Specific, User-Friendly, Robust, and rapid, Equipment free, Deliverable) criteria. As a proof of concept, we focus on oligonucleotide targets. Our detection system incorporates an activatable catalytic complex that causes the decomposition of Hydrogen Peroxide (H2O2); oxygen (O2) bubbles released in reaction serve as signal readout. The catalytic system comprises of DNA G-quadruplex and Hemin. The catalytic activity and, therefore, the signal are triggered in the presence …

Gas–Phase Studies Of C–H Activation And Dehydrogenation Of Liquid Organic Hydrogen Carrier Model Compounds, Robert S. King

Graduate Research Theses & Dissertations

In the transport of hydrogen, cryogenic methods are often utilized; however, this method is high in energy cost and not sufficiently safe in terms of release prevention. Liquid organic hydrogen carriers (LOHCs) are one of the many methods being developed for a robust and safe hydrogen energy infrastructure. One aspect of LOHCs with a rich research field as of late is dehydrogenation techniques to liberate stored hydrogen gas for energy consumption. This process currently requires excessive cost (environmental and monetary), specialty catalysts using expensive metals like palladium for the selective dehydrogenation without coking of the catalyst surface. In search for …

Demonstration And Assessment Of Dark Field And Phase X-Ray Computed Tomography, Wadiah Hamed Allahyani

Electronic Theses & Dissertations (2024 - present)

Conventional computed tomography produces a 2D slice or 3D image from multiple conventional images to avoid overlapping structures and increase visualization of the internal features of the object. A set up, macro controls and processing for computed tomography was created for the Center for X-ray Optics for the first time, and demonstrated in this work. Adding differential phase contrast to conventional x-ray images highlights edges. Two more channels of information, dark field and integrated phase, improve the contrast and increase the signal-to-noise ratios of the image. Combining these channels with computed tomography is an important development. This work is the …

A Dynamically Adapting Forecast Cone Based On Ensemble Spread, Michael N. Barletta

Electronic Theses & Dissertations (2024 - present)

Dynamically based ensemble prediction systems have gained considerable attention because they can provide a greater range of possible forecast outcomes and quantify the uncertainty in forecasts. In turn, forecasters can convey clearer messages to the public on the range of forecast scenarios and display inherent uncertainty in weather forecasts, which can be difficult to do with deterministic forecasts. Although global ensemble prediction systems have demonstrated skill in their probabilistic track predictions, the information contained within them is not always fully utilized beyond the mean forecast and standard deviation (i.e., spread). One way that these ensembles could be better employed is …