Physical Sciences and Mathematics Commons^™

Sequence Checking And Deduplication For Existing Fingerprint Databases, Tahsin Islam Sakif

Graduate Theses, Dissertations, and Problem Reports

Biometric technology is a rapidly evolving field with applications that range from access to devices to border crossing and entry/exit processes. Large-scale applications to collect biometric data, such as border crossings result in multimodal biometric databases containing thousands of identities. However, due to human operator error, these databases often contain many instances of image labeling and classification; this is due to the lack of training and throughput pressure that comes with human error. Multiple entries from the same individual may be assigned to a different identity. Rolled fingerprints may be labeled as flat images, a face image entered into a …

Synthesis And Pharmacology Of Illudalic Acid And Analogous Chemical Structures, Robert Gaston Jr

Graduate Theses, Dissertations, and Problem Reports

Natural products are the foundation of modern medicine and an inspiration for chemical innovation. Developing new synthetic strategies to complex natural products drives synthetic innovation and promotes pharmacological exploration. As bioactive secondary metabolites of fungi, illudalic acid and associated analogs have unrealized medicinal potential due to synthetic limitations. Illudalic acid is notably the first selective covalent inhibitor of the LAR-PTPs, a class of enzymes linked to many human illnesses, including stimulant addiction. The chemistry herein focuses on optimizing synthetic routes to illudalic acid and associated analogs toward exploring their pharmaceutical potential. We report a second-generation synthesis of illudinine (55% overall …

Linkages Between Atmospheric Circulation, Weather, Climate, Land Cover And Social Dynamics Of The Tibetan Plateau, Shobha Kumari Yadav

Graduate Theses, Dissertations, and Problem Reports

The Tibetan Plateau (TP) is an important landmass that plays a significant role in both regional and global climates. In recent decades, the TP has undergone significant changes due to climate and human activities. Since the 1980s anthropogenic activities, such as the stocking of livestock, land cover change, permafrost degradation, urbanization, highway construction, deforestation and desertification, and unsustainable land management practices, have greatly increased over the TP. As a result, grasslands have undergone rapid degradation and have altered the land surface which in turn has altered the exchange of heat and moisture properties between land and the atmosphere. But gaps …

Exogenous Factors That Impact Huntingtin Aggregation, Adam Skeens

Graduate Theses, Dissertations, and Problem Reports

While expansion of a polyglutamine (polyQ) domain is the immediate cause of huntingtin (htt) aggregation associated with Huntington’s Disease (HD), other cellular factors modify aggregation. These include interactions with cellular membranes, protein biding partners, molecular crowding, and proteinaceous seeds. Here, two important factors are biophysically characterized: 1) the interaction of htt with endomembranes and 2) proteinaceous seeds obtained from a variety of htt-derived peptides. In the first project, the aggregation of htt at bilayer interfaces and in the presence of divalent cations was investigated. A major cellular factor implicated in altered htt aggregation is the binding of lipids. Furthermore, the …

Ambient Ammonia Synthesis Via Microwave-Catalytic Materials And Plasma Chemistry, Siobhan Brown

Graduate Theses, Dissertations, and Problem Reports

Ammonia is critical to supporting human life on earth because of its use as fertilizer. The Haber-Bosch process to produce ammonia has been practiced for over 100 years. This process operates at high pressure and temperature to overcome the thermodynamic and kinetic limitations of the ammonia synthesis reaction thus researchers have tried to overcome it for decades. At present this process represents 1% of global energy usage and 2.5% of global CO₂ emissions. The proposed chemical looping ammonia synthesis approach seeks to reduce the environmental impact of this critical process and to elucidate microwave-catalytic principles.

This research aims to …

Optimal Design And Operation Of Integrated Hydrogen Generation And Utilization Plants, Ijiwole Solomon Ijiyinka

Graduate Theses, Dissertations, and Problem Reports

There are considerable efforts worldwide for reducing the use of fossil fuel for energy production. While renewable energy sources are being increasingly used, fossil fuel still contribute about 80% of the energy used worldwide. As a result, the level of CO₂ is still increasing fast in the atmosphere currently exceeding about 410 parts per million (ppm). For reducing CO₂ build up in the atmosphere, various approaches are being investigated. For the electric power generation sector, two key approaches are post-combustion CO₂ capture and use of hydrogen as a fuel for power generation. These two solutions can also …

On Eulerian Subgraphs And Hamiltonian Line Graphs, Yikang Xie

Graduate Theses, Dissertations, and Problem Reports

A graph {\color{black}$G$} is Hamilton-connected if for any pair of distinct vertices {\color{black}$u, v \in V(G)$}, {\color{black}$G$} has a spanning $(u,v)$-path; {\color{black}$G$} is 1-hamiltonian if for any vertex subset $S \subseteq {\color{black}V(G)}$ with $|S| \le 1$, $G - S$ has a spanning cycle. Let $\delta(G)$, $\alpha'(G)$ and $L(G)$ denote the minimum degree, the matching number and the line graph of a graph $G$, respectively. The following result is obtained. {\color{black} Let $G$ be a simple graph} with $|E(G)| \ge 3$. If $\delta(G) \geq \alpha'(G)$, then each of the following holds. \\ (i) $L(G)$ is Hamilton-connected if and only if $\kappa(L(G))\ge …

Continental Saline Environments Interpreted From Bedded Gypsum Of The Triassic Red Peak Formation (Chugwater Group), Northcentral Wyoming, Maya Yamei Bradford

Graduate Theses, Dissertations, and Problem Reports

Bedded evaporites and associated red bed siliciclastics record saline lake and groundwater systems from Permo-Triassic Pangea. A major component of these red bed and evaporite systems is bedded gypsum. However, little attention has been paid to the textures of ancient gypsum. Observations of gypsum textures can refine interpretations of depositional environment and diagenetic history. This project describes textures of bedded gypsum from an outcrop of the Triassic Red Peak Formation (Chugwater Group) near Greybull, Wyoming.

This thesis uses fieldwork, petrography, and x-ray diffraction to describe an outcrop of the upper Red Peak Formation, with a focus on textures of bedded …

Copper-Catalyzed Dehydrogenative Decarboxylation Reactions Of Carboxylic Acids To Alkenes, Michael P. Stanton

Graduate Theses, Dissertations, and Problem Reports

Linear alpha olefins (LAOs) are important building blocks in the production of linear low-density polyethylene, a plastic used in products such as shrink wraps, plastic bags, tubing, plasticizers, among others. Commercial methods for generating LAOs utilize ethylene oligomerization, but this method is reliant on fossil fuels and leads to unselective product formation. Synthesis of LAOs from renewable resources, namely carboxylic acids, by decarbonylative dehydration strategies has been well studied, however, this method has inherent drawbacks rooted in the formation of internal olefin side-products through isomerization pathways. With the goal of avoiding internal isomerization, this thesis explores a dehydrogenative decarboxylation strategy …

Interpretation Of The Tandem Mass Spectrum Of The Novel Psychoactive Substance 5f-App-Pinaca, Px-2, Christopher S. Poulos

Graduate Theses, Dissertations, and Problem Reports

Designer drugs and novel psychoactive substances (NPSs) are continuously entering the black market and causing serious health problems among users. NPSs present an especially difficult challenge to forensic chemists and toxicologists because they are not well characterized and often involve families of structurally related analogs. In crime laboratories, mass spectrometry is commonly used as a part of an analytical scheme to characterize and identify unknown analytes. Towards this end, tandem mass spectra of questioned analytes are often compared to reference spectra of standards that are either collected contemporaneously with the analyte or collected previously and stored in a database. However, …

Exploration Of Metal-Carbonyl Complexes For Decarbonylation Reactions, Rebekah C. Krupa

Graduate Theses, Dissertations, and Problem Reports

In recent years, transition metal-mediated decarbonylation reactions have emerged as an alternative to conventional cross-coupling methods due to the advantages associated with the use of carbonyl-containing functionalities as coupling electrophiles instead of organohalides found in traditional cross-coupling reactions. This, coupled with the ubiquity of carbonyl-containing compounds in pharmaceuticals and non-biodegradable chemicals, has led to the interest in developing efficient systems for transition metal-catalyzed decarbonylation. However, these reactions are commonly limited to stoichiometric amounts of metal reagents due to the strong metal-carbonyl bond formed during transition metal-mediated decarbonylation. With the goal of gaining a better mechanistic understanding of CO dissociation in …

Use Of Carbonation For Treatment Of Coal Mine Drainage To Increase Limestone Dissolution And Generate Alkalinity, Dietrich Henry Kuhlmann Iv

Graduate Theses, Dissertations, and Problem Reports

Abstract

Use of Carbonation for Treatment of Coal Mine Drainage to Increase Limestone Dissolution and Generate Alkalinity

Dietrich Kuhlmann IV

Anoxic limestone drains (ALDs) are a common component used within passive treatment systems for coal mine drainage (CMD). Contact between limestone aggregate and CMD results in limestone dissolution, producing carbonate alkalinity. Though ALDs are one of the least expensive CMD treatment technologies, alkalinity generation is limited by limestone solubility. This necessitates a long retention time (>12 hours) and sometimes results in net acidic effluent which requires additional alkalinity generation steps downstream. One way to increase calcite dissolution and alkalinity …

A Longitudinal Study Of Factors That Affect User Interactions With Social Media And Email Spam, Wojciech M. Mazurek

Graduate Theses, Dissertations, and Problem Reports

Given the rapid growth of social media and the increasing prevalence of spam, it is crucial to understand users’ interactions with unsolicited content to develop effective countermeasures against spam. This thesis focuses on exploring the factors that influence users’ decisions to interact with spam on social media and email. It builds upon prior work, which serves as a foundation for further research and conducting a longitudinal analysis. Our results are based on the analysis of 221 responses collected through an online survey. The survey not only gathered demographic information such as age, gender, and race but also collected data on …

Scene Representation And Matching For Visual Localization In Hybrid Camera Scenarios, Marcela A. Mera Trujillo

Graduate Theses, Dissertations, and Problem Reports

Scene representation and matching are crucial steps in a variety of tasks ranging from 3D reconstruction to virtual/augmented/mixed reality applications, to robotics, and others. While approaches exist that tackle these tasks, they mostly overlook the issue of efficiency in the scene representation, which is fundamental in resource-constrained systems and for increasing computing speed. Also, they normally assume the use of projective cameras, while performance on systems based on other camera geometries remains suboptimal. This dissertation contributes with a new efficient scene representation method that dramatically reduces the number of 3D points. The approach sets up an optimization problem for the …

An Empirical Analysis Of Approximation Algorithms For The Unweighted Tree Augmentation Problem, Jacob Thomas Restanio

Graduate Theses, Dissertations, and Problem Reports

In this thesis, we perform an experimental study of approximation algorithms for the tree augmentation problem (TAP). TAP is a fundamental problem in network design. The goal of TAP is to add the minimum number of edges from a given edge set to a tree so that it becomes 2-edge connected. Formally, given a tree T = (V, E), where V denotes the set of vertices and E denotes the set of edges in the tree, and a set of edges (or links) L ⊆ V × V disjoint from E, the objective is to find a set of edges …

Finite Element Modeling And Analysis Of Breech Face Impressions, James A. Hamilton

Graduate Theses, Dissertations, and Problem Reports

Finite element analysis (FEA) is a technique which has not been widely used in Forensic Science in general and firearms examination in particular. The general utility of FEA was assessed by the simulation of scenarios commonly encountered during the investigation of firearm related crimes. As a test, simulations included the perforation of a windshield and sheet metal with a 9 mm projectile, the development of pseudo subclass characteristics during the manufacturing of a breech face, and the impact of a projectile with another projectile in air and with a solid body. Results from the simulations were compared to projectiles and …

Forecasting And Optimizing Sensitivity To Low-Frequency Gravitational Waves, Andrew Ryan Kaiser

Graduate Theses, Dissertations, and Problem Reports

Pulsars are among the most exotic objects in our Universe. These rapidly
spinning, high magnetic field neutron stars can be used for a wide range of
scientific studies: from the makeup of their own extremely dense and poorly
understood interior to using their extremely regular signals to detect gravita-
tional waves (GWs). Pulsar timing continues to expand to broader communi-
ties, with larger and more sensitive radio telescopes planned and partnerships
between pulsar timing arrays (PTAs) that span the entire globe. A realm of
new physics with the detection of a background hum of gravitational waves
from black holes merging …

The Influence Of Instrumental Sources Of Variance On Mass Spectral Comparison Algorithms, Isabel Cristina Galvez Valencia

Graduate Theses, Dissertations, and Problem Reports

Current search algorithms for the identification of substances based only on their electron ionization mass spectra provide the correct compound as their top result approximately 80% of the time. One contributing factor to the ~20% deviation in the first-hit recognition rate is that traditional algorithms work by comparing the unknown spectrum to an ‘ideal’ or consensus spectrum of each reference compound. The inclusion of replicate reference spectra in a database has been shown to improve the probability of ranking the correct identity in the number one position, but the variance in ion abundances caused by different conditions or different instruments …

Drift Orbit Bifurcation Effects On Earth’S Radiation Belt Electrons, Jinbei Huang

Graduate Theses, Dissertations, and Problem Reports

Energetic charged particles trapped in the Earth’s radiation belt form a hazardous space environment for artificial electronic systems and astronauts. The study of Earth's radiation belt is becoming increasingly important with the development of communication technology, which plays a significant role in modern society. Earth’s radiation belt is highly dynamic, and the electron flux can drop by several orders of magnitude within a few hours which is called radiation belt dropout. The fast dropout of energetic electrons in the radiation belt, despite its significance, has not been thoroughly studied. One of the most compelling outstanding questions in Earth's radiation belt …

Estimate Of The Random Match Frequency Of Acquired Characteristics In A Forensic Footwear Database, Alyssa N. Smale

Graduate Theses, Dissertations, and Problem Reports

When analyzing footwear impression evidence, one of the goals of an examiner is to determine if an exemplar shoe could be the source of an impression found at a crime scene. This opinion is based on an assessment of the similarity of class characteristics and randomly acquired characteristics (RACs) between the known and questioned impressions, as well as the rarity of the observed characteristics. The primary aim of this research was to estimate the random match frequency of randomly acquired characteristics (RAC-RMF) within a forensic footwear database to determine the frequency of RACs with geometric similarity occurring in the same …

Quantifying Variation In High-Quality Footwear Replicate Impressions, Samantha K. Brady

Graduate Theses, Dissertations, and Problem Reports

A footwear impression collected at a crime scene can provide information about the shoe that created it, yielding investigative leads, excluding persons-of-interest, and linking evidence between cases. The analysis of footwear evidence often requires the preparation of test impressions from known exemplar shoes created under controlled laboratory conditions for comparison to questioned impressions. The goal of these comparisons is to evaluate the degree of similarities and differences between the questioned impression and potential sources.

Given that this comparison leads to an assessment of the nature and degree of agreement between questioned and known impressions, it is important to characterize the …

Finite Matroidal Spaces And Matrological Spaces, Ziyad M. Hamad

Graduate Theses, Dissertations, and Problem Reports

The purpose of this thesis is to present new different spaces as attempts to generalize the concept of topological vector spaces. A topological vector space, a well-known concept in mathematics, is a vector space over a field \mathbb{F} with a topology that makes the addition and scalar multiplication operations of the vector space continuous functions. The field \mathbb{F} is usually \mathbb{R} or \mathbb{C} with their standard topologies. Since every vector space is a finitary matroid, we define two spaces called finite matroidal spaces and matrological spaces by replacing the linear structure of the topological vector space with a finitary matroidal …

Discovering And Understanding High Performance Materials Using Density Functional Theory: Quantum Mechanical Simulations And The Consequences Of Symmetry, Olivia M. Pavlic

Graduate Theses, Dissertations, and Problem Reports

There are two primary ways that atomic level modeling data is used: materials prediction and understanding materials properties. This dissertation work encom- passes two studies, each of which explore one application. Both studies rely on the highly successful density functional theory (DFT) formalism but differ in that two different implementations of DFT are used on two different high performance materials. The first study on bulk magnesium (Mg) metal alloys explores materials prediction and relies on VASP, a commercially maintained plane-wave DFT code which has been used extensively to successfully study a wide range of materials. [1] The approach used in …

Generative Prior For Unsupervised Image Restoration, Ahmed Cheikh Sidiya

Graduate Theses, Dissertations, and Problem Reports

The challenge of restoring real world low-quality images is due to a lack of appropriate training data and difficulty in determining how the image was degraded. Recently, generative models have demonstrated great potential for creating high- quality images by utilizing the rich and diverse information contained within the model’s trained weights and learned latent representations. One popular type of generative model is the generative adversarial network (GAN). Many new methods have been developed to harness the information found in GANs for image manipulation. Our proposed approach is to utilize generative models for both understanding the degradation of an image and …

Methods For Analyzing Physics Student Retention And Physics Curricula, John Darrell Hansen

Graduate Theses, Dissertations, and Problem Reports

Retention of students in college has been a concern of academic institutions for many years. In the last two decades, the focus on student retention in STEM fields has intensified. The current graduation rate of students in science, technology, engineering and mathematics (STEM) fields is well below that required to fill the projected need of STEM professionals. The work presented in this dissertation investigates the problem of student retention in physics programs. Four studies were performed. The first identifies the relationships between student retention and pre-college and early-college academic factors at an eastern U.S. university using logistic regression and Bayesian …

Relationships Between Geochemistry, Carbon Content, And Grain Size In Clastic Cave Sediments, Rebekah Rose Nicholas

Graduate Theses, Dissertations, and Problem Reports

Understanding geochemical and physical properties of cave sediment gives insight to sediment characterization and carbon storage in the cave system. Previous work on clastic sediments largely encompasses physical properties, neglecting the importance of geochemical parameters on sediment deposition.

This study reports physical and chemical properties of sediment cores from three caves: two caves in Puerto Rico and one cave in Virginia. A total of 25 cores were used in this study; 6 of these cores were new and collected in 2022 from Butler Cave (BTC) in Virginia to focus on the effects of water level. Core samples were analyzed for …

Application Of Computational Biophysics Techniques To Characterize Cell Membrane-Associated Events, Kyle Billings

Graduate Theses, Dissertations, and Problem Reports

Cell membranes are crowded environments which can modulate protein structure-function relationships through interaction with lipids, other proteins, carbohydrate structures and so on. This work focuses the impact of the membrane environment on two varieties of peptides: Microbial rhodopsin proteins, and cyclic peptides.

Life on Earth is dependent on the ability of plants and microbes to harness sunlight for energy production. Their ability to transform light into carbohydrates requires tailor-made machinery, and for a wealth of microorganisms, microbial rhodopsin proteins (MR) are critical for maintaining the concentration gradients used to produce the energy molecule Adenosine triphosphate (ATP). The central retinal molecule …

Exploiting The Advantages And Overcoming The Challenges Of The Cable In A Tethered Drone System, Rogerio Rodrigues Lima

Graduate Theses, Dissertations, and Problem Reports

This dissertation proposes solutions for motion planning, localization, and landing of tethered drones using only tether variables. A tether-based multi-model localization framework for tethered drones is proposed. This framework comprises three independent localization strategies based on a different model. The first strategy uses simple trigonometric relations assuming that the tether is taut; the second method relies on a set of catenary equations for the slack tether case; the third estimator is a neural network-based predictor that can cover different tether shapes. Multi-layer perceptron networks previously trained with a dataset comprised of the tether variables (i.e., length, tether angles on the …

Examining The Relations Among Academic And Non-Cognitive Factors And Student Achievement, Dona Sachini Hasanjalie Hewagallage

Graduate Theses, Dissertations, and Problem Reports

Since the 1980s, Physics Education Research (PER) has explored the factors influencing students' success in college. This manuscript reports three different studies to understand the impact of different factors on students' college physics achievement. The first study explored several academic (high school physics preparation, high school preparation, math readiness, and ACT or SAT verbal and mathematics scores) and non-cognitive (self-efficacy, personality, belonging, grade expectation, and demographic) factors using correlation and linear regression analysis to understand their relation to students' physics conceptual understanding measured by the Force and Motion Conceptual Evaluation (FMCE). High school preparation was found to be the most …

Investigating The Interactions Of The Iron-Sulfur Mitochondrial Protein, Mitoneet With Its Binding Partners, Ebenezer Osei Newton

Graduate Theses, Dissertations, and Problem Reports

MitoNEET belongs to the CDGSH Iron-Sulfur Domain (CISD)-gene family of proteins and is a [2Fe-2S] cluster-containing protein found on the outer membrane of mitochondria. The specific functions of mitoNEET/CISD1 remain to be fully elucidated, but the protein is involved in regulating mitochondrial bioenergetics in several metabolic diseases. Unfortunately, drug discovery efforts targeting mitoNEET to improve metabolic disorders are hampered by the lack of ligand-binding assays for this mitochondrial protein. We have developed a protocol amenable for high-throughput screening (HTS) assay, by modifying an ATP fluorescence polarization method to facilitate drug discovery targeting mitoNEET. Based on our observation that adenosine triphosphate …