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Full-Text Articles in Physical Sciences and Mathematics

Canine Parasites In Southern Nevada Urban Dog Parks: Paravec Study, Miklo Azrael A. Alcala Aug 2024

Canine Parasites In Southern Nevada Urban Dog Parks: Paravec Study, Miklo Azrael A. Alcala

UNLV Theses, Dissertations, Professional Papers, and Capstones

While dogs are one of humans’ greatest companions, they also serve as hosts for a multitude of parasites. Urban dog parks serve as environments where the transmission of diseases is likely to occur. Exposure to infective agents, contained within the soil, intermediate hosts (e.g., rodents, rabbits), and feces, can directly affect the health of dogs and their owners. Other factors that can further influence canine health include age, previous diagnoses of parasites/diseases, and migration. Many dog owners visit dog parks to encourage socialization and exercise. Such activities are meant to improve health, but unawareness of microbiological organisms can lead to …


Optimization Of Mass Spectrometry-Based Methods For Low-Input And Spatial Proteomics, Andikan Jones Nwosu Aug 2024

Optimization Of Mass Spectrometry-Based Methods For Low-Input And Spatial Proteomics, Andikan Jones Nwosu

Theses and Dissertations

Eukaryotic cells are highly heterogeneous. These cells are arranged into different compartments, carrying out separate functions and facilitating biological processes. Proteins are the effector biomolecules targeted to subcellular locations that help fulfill specific tasks in living organisms. Spatial proteomics can help unravel molecularly how protein abundance and localization are altered in cells, which is not feasible in traditional bulk-scale proteomics. To achieve this, our lab has developed a miniaturized sample processing platform called nanoPOTS, reduced separation columns' inner diameter to increase ionization efficiency and concentrate analytes for mass spectrometers and optimized data acquisition modes for increasing proteome coverage in spatial …


Excited State Processes In Radical Elaborated Platinum Donor-Acceptor Complexes, Sangita Paudel Jul 2024

Excited State Processes In Radical Elaborated Platinum Donor-Acceptor Complexes, Sangita Paudel

Chemistry and Chemical Biology ETDs

Organo-transition metal complexes are being widely studied to understand their photophysical properties for their wide range of applications as efficient emitters in organic light emitting diodes (OLEDs), light emitting electrochemical cells (LEECs), etc. Cyclometalated organo-transition metal complexes such as cyclometalated square planar platinum(II) complexes are becoming suitable candidates for such applications because of their highly efficient luminescence. Understanding the excited properties of such complexes is useful in designing highly efficient and color tunable phosphors with desired excited state lifetimes. We aim to explore the influence of radical substituents on electronic structure, luminescence quantum efficiencies, and excited state lifetimes by synthesizing …


Increasing The Robustness Of Machine Learning By Adversarial Attacks, Gourab Mukhopadhyay Jul 2024

Increasing The Robustness Of Machine Learning By Adversarial Attacks, Gourab Mukhopadhyay

Theses and Dissertations

By perturbation or physical attacks any machine can be fooled into predicting something else other than the intended output. There are training data based on which the model is trained to predict unknown things. The objective was to create noises and shades of different levels on the images and do experiments for measuring accuracy and making the model classify the traffic signs. When it comes to adding shades to the pictures, pixels were modified for three different layers of the pictures. The experiment also shows that with the shadows getting deeper, the accuracies drop significantly. Here, some changes in pixels …


The Role Of Sensing Modalities In Shaping Collective Motion And Group Behavior, Poorendra P. Ramlall Jul 2024

The Role Of Sensing Modalities In Shaping Collective Motion And Group Behavior, Poorendra P. Ramlall

Doctoral Dissertations and Master's Theses

Collective behavior refers to the coordinated movements that emerge from simple interactions between individuals within a group. Traditionally, researchers have modeled these interactions assuming individuals can sense their surroundings in all directions, like having eyes all around their heads. While this is a useful simplification, it does not capture the diverse ways animals actually sense the world. In this thesis, we take inspiration from the natural world, particularly from animals like bats and dolphins that use a combination of hearing and sight to navigate their environments. We explore how combining these sensory cues in a three-dimensional space affects the way …


Personalized Driving Using Inverse Reinforcement Learning, Rodrigo J. Gonzalez Salinas Jul 2024

Personalized Driving Using Inverse Reinforcement Learning, Rodrigo J. Gonzalez Salinas

Theses and Dissertations

This thesis introduces an autonomous driving controller designed to replicate individual driving behaviors based on a provided demonstration. The controller employs Inverse Reinforcement Learning (IRL) to formulate the reward function associated with the provided demonstration. IRL is implemented through a dual-feedback loop system. The inner loop utilizes Q-learning, a model-free reinforcement learning technique, to optimize the Hamilton-Jacobi-Bellman (HJB) equation and derive an appropriate control solution. The outer loop leverages this derived control solution to generate parameters for the reward function, which are subsequently integrated into the HJB equation. The ultimate control policy is deduced from the final reward function obtained …


Enhancing Security In Modern Medical Devices: The Medicalharm Methodology And Cyberllama2, Emmanuel Kwarteng Jul 2024

Enhancing Security In Modern Medical Devices: The Medicalharm Methodology And Cyberllama2, Emmanuel Kwarteng

Dissertations (1934 -)

With the rapid growth of Modern Medical Devices (MMDs) and their increasing connectivity to enhance patient care, concerns about security, privacy, and safety are paramount. If compromised, these devices can expose sensitive patient information and harm patients. Therefore, securing MMDs against cyber-attacks is critical. Threat modeling, mandated by the FDA as a premarket submission requirement in the MMD domain, serves as the first defense mechanism. However, our investigation of 119 participants from various MMD manufacturing companies revealed a need for a tailored threat modeling methodology that considers both patient safety and device complexity. To address this, we present MEDICALHARM, a …


Space Radiation Assessment And Mitigation: Meeting The Growing Demand For Shielding Solutions By Enhancing Models And Exploring Novel Shielding Opportunities, M. Laura Sorgi Johann Jul 2024

Space Radiation Assessment And Mitigation: Meeting The Growing Demand For Shielding Solutions By Enhancing Models And Exploring Novel Shielding Opportunities, M. Laura Sorgi Johann

Doctoral Dissertations and Master's Theses

The rapid growth of satellite technology and the increasing presence of vulnerable technology and human life in space have highlighted the need for improved shielding materials. Industry standard protocols for shielding are being pushed to their limits as we gain a deeper understanding of the harsh space environment and as chip sizes approach the scale of radiation wavelengths. Furthermore, the commercialization of space is attracting interest from industries such as pharmaceuticals and semiconductor crystal growing, as they explore the potential benefits of zero-gravity production environments. However, the eagerness to develop lighter shielding and the lack of consideration for existing tools …


Striking At The Root: A Categorization Of Dns Clients, Tyler Dean Jul 2024

Striking At The Root: A Categorization Of Dns Clients, Tyler Dean

Theses and Dissertations

The Domain Name System (DNS) root servers have provided a useful look into the DNS and internet ecosystems for decades. We present a categorization of clients querying DNS root servers. Using two clustering algorithms on DNS traffic sampled in 2020, we can predict the structure and volume of queries originating from different types of clients. Previous research has used unsupervised techniques to better understand DNS traffic patterns, but none have, to our knowledge, considered clients beyond those driven by queries from end users. By performing clustering on IP addresses rather than on individual queries, we are able to examine the …


Synthesis Of Portions Of An Acinetobacter Baumannii Lipooligosaccharide (Los), Brandon Conrad Jul 2024

Synthesis Of Portions Of An Acinetobacter Baumannii Lipooligosaccharide (Los), Brandon Conrad

LSU Doctoral Dissertations

Glycoconjugate vaccines have become an effective strategy for protection against an array of globally persistent diseases resulting from pathogenic bacteria such as Haemophilus influenzae type b (Hib), Neisseria meningitidis, and Salmonella enterica serotype Typhi. Comprised of a carbohydrate (referred to as glycan) covalently inked to a carrier protein, these vaccines can initiate adaptive immunity by inducing B and T cell responses once in the lymphatic system. This is particularly relevant for infants two years of age and younger whose immune systems are not fully developed. A continuously emerging threat in clinical settings, Acinetobacter baumannii is a Gram-negative bacterium …


Strong Gelfand Pairs Of Some Finite Groups, Joseph E. Marrow Jul 2024

Strong Gelfand Pairs Of Some Finite Groups, Joseph E. Marrow

Theses and Dissertations

Strong Gelfand pairs describe a relation between a group and a subgroup, using a relation between inner products of their characters. We find all strong Gelfand pairs of the dihedral and dicyclic groups, and several of the sporadic groups. We provide some results for the strong Gelfand pairs of the affine linear groups, in addition to the exceptional classical groups $\mathrm{Sp}_4(q)$ for $q$ a power of $2$.


Documentation Of Norm Negotiation In A Secondary Mathematics Classroom, Michelle R. Bagley Jul 2024

Documentation Of Norm Negotiation In A Secondary Mathematics Classroom, Michelle R. Bagley

Theses and Dissertations

While previous mathematics education research has shown that norms can change in mathematics classrooms, little research has closely documented the struggles, concessions, and compromises involved in the negotiation process. Negotiating norms is a complex process entailing deliberate teacher moves intended to promote norms, often met with misunderstandings or resistance from students. This thesis documented the negotiation process that occurred when a teacher attempted to require conceptual explanations from students who had not previously been accustomed to doing so. I recorded six days of instruction in a 9th grade algebra unit, transcribed the class discussions, and inferred norms "at play" for …


Monotone Functions On General Measure Spaces, Alejandro Santacruz Hidalgo Jul 2024

Monotone Functions On General Measure Spaces, Alejandro Santacruz Hidalgo

Electronic Thesis and Dissertation Repository

Given a measure space and a totally ordered collection of measurable sets, called an ordered core, the notion of a core decreasing function is introduced and used to generalize monotone functions to general measure spaces. The least core decreasing majorant construction, the level function construction, and the greatest core decreasing minorant, already known for functions on the real line, are extended to this general setting. A functional description of these constructions is provided and is shown to be closely related to the pre-order relation of functions induced by integrals over the ordered core.

For an ordered core, the down space …


Quantum Classical Algorithm For Solving The Hubbard Model Via Dynamical Mean-Field Theory, Anshumitra Baul Jul 2024

Quantum Classical Algorithm For Solving The Hubbard Model Via Dynamical Mean-Field Theory, Anshumitra Baul

LSU Doctoral Dissertations

Modeling many-body quantum systems is widely regarded as one of the most promising applications for near-term noisy quantum computers. However, in the near term, system size limitation will remain a severe barrier for applications in materials science or strongly correlated systems. A promising avenue of research is to combine many-body physics with machine learning for the classification of distinct phases. I present a workflow that synergizes quantum computing, many-body theory, and quantum machine learning (QML) for studying strongly correlated systems. In particular, it can capture a putative quantum phase transition of the stereotypical strongly correlated system, the Hubbard model. Following …


Analytic Properties Of Quantum States On Manifolds, Manimugdha Saikia Jul 2024

Analytic Properties Of Quantum States On Manifolds, Manimugdha Saikia

Electronic Thesis and Dissertation Repository

The principal objective of this study is to investigate how the Kahler geometry of a classical phase space influences the quantum information aspects of the quantum Hilbert space obtained from geometric quantization and vice versa. We associated states with subsets of a product of two integral Kahler manifolds using a quantum line bundle in a particular manner. We proved that the states associated this way are separable when the subset is a finite union of products. We presented an asymptotic result for the average entropy over all the pure states on the Hilbert space H0(M1,L1 …


Investigating The Effect Of Bentonite Clay Compaction Density On The Corrosion Of Copper Materials, Claire Samantha Tully Jul 2024

Investigating The Effect Of Bentonite Clay Compaction Density On The Corrosion Of Copper Materials, Claire Samantha Tully

Electronic Thesis and Dissertation Repository

As per international consensus on the best practice for managing used nuclear fuel (UNF), the Nuclear Waste Management Organization (NWMO) plan to isolate and contain UNF within a multiple-barrier system, underground in a deep geological repository (DGR). In the proposed design, used fuel bundles will be sealed in copper-coated carbon steel used fuel containers (UFCs), encased in blocks of highly compacted bentonite clay, and emplaced ~500-800 m (depending on host rock geology) below ground. Any gaps between the rock walls and the compacted bentonite blocks will be filled with a bentonite gap fill material (GFM).

The compacted bentonite material serves …


Diving Deeper Into Supercuspidal Representations, Prerna Agarwal Jul 2024

Diving Deeper Into Supercuspidal Representations, Prerna Agarwal

LSU Doctoral Dissertations

In 2013, Reeder and Yu introduced certain low positive depth supercuspidal representations of $p$-adic groups called \textit{epipelagic} representations. These representations generalize the simple supercuspidal representations of Gross and Reeder, which have the lowest possible depth. Epipelagic representations also arise in recent work on the Langlands correspondence; for example, simple supercuspidals appear in the automorphic data corresponding to the Kloosterman $l$-adic sheaf. In this thesis, we take a first step towards the construction of ``\textit{mesopelagic} representation (of Iwahori type)'' which are the higher depth analogues of simple supercuspidal representations. We see that these constructions can be done in a similar way …


Precision Deuteration And Hydrofunctionalization Of Aryl Alkynes And Alkenes, Samantha E. Sloane Jul 2024

Precision Deuteration And Hydrofunctionalization Of Aryl Alkynes And Alkenes, Samantha E. Sloane

Dissertations (1934 -)

The similar nature of the hydrogen atom to its isotope, deuterium, allows for the simple exchange of hydrogen atoms for deuterium atoms in drug molecules to alter the absorption, distribution, metabolism, and excretion properties. Installing the deuterium functionality into a specific site in the molecule is essential. Selective hydrofunctionalization reactions of alkynes and alkenes using the highly reactive catalytic Cu–H species have been well developed, and synthetic organic chemistry methods to selectively incorporate one or two deuterium atoms into the benzylic site of organic compounds, a key metabolic position, are elusive. A Cu–H catalytic approach offers selectivity and reactivity to …


Empowering Informed Decision-Making In Mental Health Care: A Web-Based Recommendation System For Mobile App Selection, Md Romael Haque Jul 2024

Empowering Informed Decision-Making In Mental Health Care: A Web-Based Recommendation System For Mobile App Selection, Md Romael Haque

Dissertations (1934 -)

In 2022, 23.1% of adults in the United States (77 million individuals) were affected by mental health (MH) concerns. Due to the inaccessibility and high cost of traditional treatment, around 55% of people with severe mental illnesses do not receive treatment. Mental health concerns are prevalent, affecting a significant portion of the population in the United States. Traditional treatment options are often inaccessible and expensive, leaving many people without essential mental healthcare. However, the rise of mobile technologies has given rise to a promising solution: mobile mental health applications (MMHAs). These apps offer greater accessibility and affordability, potentially expanding mental …


Synthesis And Computational Studies Of Α- And Δ-Substituted Macrocyclic Europium And Ytterbium Complexes, Delainey Amara Winder Jul 2024

Synthesis And Computational Studies Of Α- And Δ-Substituted Macrocyclic Europium And Ytterbium Complexes, Delainey Amara Winder

Dissertations and Theses

The uses of macrocyclic lanthanide complexes are vast, with many targeted MRI contrast agents at the forefront of the field. Many of these are ParaCEST agents, which require exchangeable protons accessible on the macrocycle and the slow exchange of coordinated water molecules. The substitution at both the α- and δ-carbon on the amide pendant arm of these macrocyclic lanthanide complexes can lock bulky groups on the δ-carbon to a pseudo-axial position. When the α- and δ-carbons have the same chirality, the bulky group will be pseudo-equatorial, and when the chirality is opposed, the bulky group will be pseudo-axial. By performing …


Exploring The Chemistry Of Bis(Azido)Phosphine Chalcogenides And The Pursuit Of Isolable Phosphinidene Chalcogenides, John Lortie Jul 2024

Exploring The Chemistry Of Bis(Azido)Phosphine Chalcogenides And The Pursuit Of Isolable Phosphinidene Chalcogenides, John Lortie

Electronic Thesis and Dissertation Repository

The study of low-coordinate species and the pursuit of interesting bonding motifs has revealed new reactivity modes for main-group compounds, akin to transition metals, in the past two decades. An underexplored class of two-coordinate phosphorus compound is a phosphinidene sulfide, which has yet to be isolated in the solid-state with an accompanying crystal structure. This dissertation explores strategies towards the synthesis and reactivity of low-coordinate phosphinidene chalcogenide species, and related compounds supported by strongly pi-donating or weakly pi-donating environments. While the primary synthetic targets remained elusive, significant discoveries were made towards new methods of preparing electron rich phosphines, and the …


Leveraging Intersubject Representational Similarity Analysis To Explore Individual Differences In Early Life Adversity And Cortico-Amygdala Connectivity In A Preadolescent Sample, Amira Hmidan Jul 2024

Leveraging Intersubject Representational Similarity Analysis To Explore Individual Differences In Early Life Adversity And Cortico-Amygdala Connectivity In A Preadolescent Sample, Amira Hmidan

Electronic Thesis and Dissertation Repository

Preadolescence is a critical developmental phase characterized by changes in the functional connectivity (FC) between the cortex and amygdala, which are essential for emotional processing and regulation. Early life adversity (ELA), such as exposure to childhood maltreatment, familial dysfunction, and poverty, is associated with negative physical and mental health outcomes (Felitti et al., 1998). Emerging research indicates that disturbances in cortico-amygdala FC could act as a mechanism linking ELA to various mental health issues; however, most focus on adult populations and overlook individual differences. Here, intersubject representational similarity analysis (IS-RSA) was leveraged to explore how individual variations in ELA relate …


Asymptotic Formula For Scattering Problems Related To Thin Metasurfaces, Zachary Jermain Jul 2024

Asymptotic Formula For Scattering Problems Related To Thin Metasurfaces, Zachary Jermain

LSU Doctoral Dissertations

The goal of this work is to develop an asymptotic formula for the behavior of a scattered electromagnetic field in the presence of a thin metamaterial known as a metasurface. By using a carefully chosen Green’s function and the single and double layer potentials we analyze the perturbed scattering problem in the presence of the metamaterial and a background scattering problem. By using Lippman-Schwinger type representation formulas for the two fields we develop the asymptotic formula for the perturbed field. From here we prove the asymptotic formula holds up to a specific error term based on the size of the …


Topics In Photonic Quantum Technology: Polarization Entanglement Dynamics In Optical Fibers And Low-Light Imaging., Pratik J. Barge Jul 2024

Topics In Photonic Quantum Technology: Polarization Entanglement Dynamics In Optical Fibers And Low-Light Imaging., Pratik J. Barge

LSU Doctoral Dissertations

Recent advances in quantum photonics promise transformative impacts on computing, communication, sensing, and imaging. This thesis explores two areas in photonic quantum technology: polarization entanglement dynamics in optical fibers and low-light imaging. Optical fibers are the most suitable medium for photonic qubits and long-distance entanglement distribution is a critical requirement to realize quantum technologies. We study the decay of polarization-entanglement of the Bell state photons propagating through imperfect optical fibers with spatially fluctuating refractive index. Furthermore, to extend the distribution distance, we propose the use of dynamical decoupling in the optical fiber using half waveplates and show that significant improvement …


Riesz Particle Markov Chain Monte Carlo Methods, Xiongming Dai Jul 2024

Riesz Particle Markov Chain Monte Carlo Methods, Xiongming Dai

LSU Doctoral Dissertations

Markov chain Monte Carlo (MCMC) methods are simulations that explore complex statistical distributions, while bypassing the cumbersome requirement of a specific analytical expression for the target. This stochastic exploration of an uncertain parameter space comes at the expense of a large number of ``burn-in'' samples, and the computational complexity leads to the curse of dimensionality. Although at the exploration level, some methods have been proposed to accelerate the convergence of the algorithm, such as tempering, Hamiltonian Monte Carlo, Rao-redwellization, and scalable methods for better performance, they cannot avoid the stochastic nature of this exploration. We develop algorithms for the energy …


Knowledge-Grounded Natural Language Understanding Of Biomedical And Clinical Literature, Xindi Wang Jul 2024

Knowledge-Grounded Natural Language Understanding Of Biomedical And Clinical Literature, Xindi Wang

Electronic Thesis and Dissertation Repository

Natural Language Understanding (NLU) resides at the intersection of artificial intelligence, linguistics, and computer science, with the goal of empowering machines to comprehend and interpret human languages in a way that is both significant and contextually pertinent. The intrinsic complexity of human language, marked by its subtleties, cultural variances, and dependence on context, poses a significant challenge to NLU. The real world is a vast repository of knowledge that encompasses not only facts but also complex relationships, dynamic concepts, and cultural subtleties. This external knowledge represents the context that is often implicitly assumed in human communication. For machines to fully …


Investigations And Characterization Of Loud Transient Noise In Advanced Ligo Detectors, Shania Nichols Jul 2024

Investigations And Characterization Of Loud Transient Noise In Advanced Ligo Detectors, Shania Nichols

LSU Doctoral Dissertations

In the era of gravitational wave (GW) astronomy, the detection of cosmic events such as black hole and neutron star mergers has become routine due to the Advanced LIGO (aLIGO) detectors. However, the sensitivity of these detectors also makes them susceptible to loud transient noise, which can obscure GW signals. This thesis investigates loud transient noise with a Signal-to-Noise Ratio (SNR) greater than 100, focusing particularly on the most extreme transients with SNR exceeding 1000.

We begin by analyzing the impact of loud transient noise on the binary neutron star (BNS) range of aLIGO detectors across observation runs O2, O3, …


Mixstm: Adapting The Structural Topic Model For A Quantitative Analysis Of Focus Group Data, Pascale A. Nevins Jul 2024

Mixstm: Adapting The Structural Topic Model For A Quantitative Analysis Of Focus Group Data, Pascale A. Nevins

Electronic Thesis and Dissertation Repository

The Structural Topic Model (STM) incorporates external information about expected document-topic proportions to enhance the model. Motivated by focus groups, whose transcripts represent text data inherently grouped by session, we propose three extensions to the STM: 1) mean document-topic proportion estimation using a regression with random effects; 2) partitioned estimation of group-specific topic covariance matrices; and 3) a post hoc mixed effects regression on topic prevalence which incorporates latent variable uncertainty into the coefficient estimates. We explore the utility of these modifications through simulated examples and apply them to focus group transcripts from a pan-Canadian study on homelessness. The new …


Synoptic Drivers Of Extreme Precipitation In The Upper Yuba Watershed Of California, Emma Nichole Russell Jul 2024

Synoptic Drivers Of Extreme Precipitation In The Upper Yuba Watershed Of California, Emma Nichole Russell

Dissertations and Theses

The United States state of California is vulnerable to both droughts and extreme precipitation events due to the timing and processes of precipitation in the region. California's annual precipitation is dependent on a few strong storms and in addition to its Mediterranean climate, leads to great variability in precipitation both within and across years. While efforts to reduce the impacts of extreme precipitation events have been implemented, forecasting for these events remains a challenge in regions with complex terrain and dynamic meteorological drivers. In order to improve forecasting and preparedness for such events, it is important to understand the range …


Design Of Long-Distance Entanglement Distribution Protocols For Quantum Networks, Stav Haldar Jul 2024

Design Of Long-Distance Entanglement Distribution Protocols For Quantum Networks, Stav Haldar

LSU Doctoral Dissertations

Future quantum technologies such as quantum communication, quantum sensing, and distributed quantum computation, will rely on networks of shared entanglement between spatially separated nodes. Distributing entanglement between these nodes, especially over long distances, currently remains a challenge, due to limitations resulting from the fragility of quantum systems, such as photon losses, non-ideal measurements, and quantum memories with short coherence times. In the absence of full-scale fault-tolerant quantum error correction, which can in principle overcome these limitations, we should understand the extent to which we can circumvent these limitations. In this work, we provide improved protocols and policies for entanglement distribution …