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Full-Text Articles in Physical Sciences and Mathematics

A Second Homotopy Group For Digital Images, Gregory Lupton, Oleg R. Musin, Nicholas A. Scoville, P. Christopher Staecker, Jonathan Treviño-Marroquín Aug 2024

A Second Homotopy Group For Digital Images, Gregory Lupton, Oleg R. Musin, Nicholas A. Scoville, P. Christopher Staecker, Jonathan Treviño-Marroquín

School of Mathematical & Statistical Sciences Faculty Publications

We define a second (higher) homotopy group for digital images. Namely, we construct a functor from digital images to abelian groups, which closely resembles the ordinary second homotopy group from algebraic topology. We illustrate that our approach can be effective by computing this (digital) second homotopy group for a digital 2-sphere.


A Coarse-Grained Molecular Dynamics Study Of Gas Hydrate Formation And Dissociation, Meisam Adibifard Aug 2024

A Coarse-Grained Molecular Dynamics Study Of Gas Hydrate Formation And Dissociation, Meisam Adibifard

LSU Doctoral Dissertations

The study of gas hydrates has increased significantly over the last two decades because of their potential application in energy storage, production and transportation, water desalination, refrigeration, gas separation, etc. There is a significant interest in commercially developing natural gas hydrates because the energy content of methane hydrate reservoirs (MHRs) is at least twice that of all conventional fossil fuels combined. Additionally, due to the higher storage capacity of hydrates, it is proposed to sequester CO2 in the form of CO2 hydrate, thereby reducing the amount of greenhouse gases. Hence, hydrates offer a dual solution to two of …


Spatial Optimism And Cross-Over Effects In The Perceptions Of Interconnected Wildfire, Flood, And Mudslide Hazards, Douglas Houston, Omar Pérez Figueroa, Ariane Jong-Levinger, Brett F. Sanders Aug 2024

Spatial Optimism And Cross-Over Effects In The Perceptions Of Interconnected Wildfire, Flood, And Mudslide Hazards, Douglas Houston, Omar Pérez Figueroa, Ariane Jong-Levinger, Brett F. Sanders

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Communities near the wildland urban interface (WUI) are exposed to a mix of three interconnected hazards (wildfire, flood, and mudslide), and understanding multi-hazard perceptions is critically important for emergency preparation and hazard mitigation—particularly given the WUI’s rapid expansion and intensifying environmental hazards. Based on a survey of residents living near recent burn scars in Southern California, we document cross-over effects in hazard perceptions, where resident experience with one hazard was associated with greater hazard rankings for other hazards. Additionally, for all three hazards analyzed we document perceptions of increasing hazard levels with increasing spatial scales (home, near-home, neighborhood, and community), …


Transforming Computer Science Pedagogy: An Exploration Of Self-Recorded Videos (Srv) As A Teaching And Evaluation Tool, Hussam Ghunaim Aug 2024

Transforming Computer Science Pedagogy: An Exploration Of Self-Recorded Videos (Srv) As A Teaching And Evaluation Tool, Hussam Ghunaim

Computer Science Faculty Publications

This study aims to introduce Self-Recorded Videos (SRV) as a novel method to help improve students’ performance in coding assignments in computer science courses. To our best knowledge, this is the first time the SRV method is applied in the context of computer science classes. The study was conducted with a sample size of 41 students who were registered in the online CSCI 331 Operating Systems course at Fort Hays State University. These students were given specific instructions to create Self-Recorded Videos SRVs for every coding assignment they were tasked with. This approach was designed to encourage students to engage …


Signatures Of Fluid-Rock Interactions In Shallow Parts Of The San Andreas And San Gabriel Faults, Southern California, James P. Evans, Kaitlyn Crouch, Caroline Studnicky, Sharon Bone, Nicholas Edwards, Samuel M. Webb Aug 2024

Signatures Of Fluid-Rock Interactions In Shallow Parts Of The San Andreas And San Gabriel Faults, Southern California, James P. Evans, Kaitlyn Crouch, Caroline Studnicky, Sharon Bone, Nicholas Edwards, Samuel M. Webb

Geosciences Faculty Publications

We examine deformed crystalline bedrock in the upper parts of the active San Andreas and ancient San Gabriel Faults, southern California, to 1) determine the nature and origin of micro-scale composition and geochemistry of fault-related rocks, 2) constrain the extent of fluid-rock interactions, and 3) determine the interactions between alteration, mineralization, and deformation. We used drill cores from a 470 m long inclined borehole through the steep-dipping San Gabriel Fault and from seven inclined northeast-plunging boreholes across the San Andreas Fault zone to 150 m deep to show that narrow fault cores 10 cm to 5 m wide lie within …


Electron Rich Cobaltocenium Derivatives As Tunable Mechanophores For Mechanochemistry, Luis Daniel Ramos Aug 2024

Electron Rich Cobaltocenium Derivatives As Tunable Mechanophores For Mechanochemistry, Luis Daniel Ramos

Theses and Dissertations

In this dissertation, metallocene-containing polymers are investigated and probed for tunability in mechanochemistry. These metallocene moieties are experimentally and computationally characterized.

In chapter 1, relevant background and recent developments of metallocene-containing polymers are discussed. Additionally, the field of mechanochemistry is briefly introduced including applications and future directions within the field.

In chapter 2, design and synthesis of these metallocene-containing polyelectrolytes via ring opening metathesis polymerization (ROMP) are outlined. These polymers then undergo mechanophore activation via ultrasonication and relevant analysis and characterization of polymers both before and after ultrasonication are detailed. These polymers are comprised of differing electron donating substituents on …


08.19.2024 Orsp Connect, Liz Williamson Aug 2024

08.19.2024 Orsp Connect, Liz Williamson

ORED Newsletter

Lei Cao NSF award

FDP Meeting Summaries Available

August LINC Lunch

Collaboration Opportunities


Modeling, Analysis, Approximation, And Application Of Viscoelastic Structures And Anomalous Transport, Yiqun Li Aug 2024

Modeling, Analysis, Approximation, And Application Of Viscoelastic Structures And Anomalous Transport, Yiqun Li

Theses and Dissertations

(Variable-order) fractional partial differential equations are emerging as a competitive means to integer-order PDEs in characterizing the memory and hereditary properties of physical processes, e.g., anomalously diffusive transport, viscoelastic mechanics and financial mathematics, and thus have attracted widespread attention. In particular, optimal control problems governed by fractional partial differential equations are attracting increasing attentions since they are shown to provide competitive descriptions of challenging physical phenomena. Nevertheless, variable-order fractional models exhibit salient features compared with their constant-order analogues and introduce mathematical difficulties that are not typical encountered in the context of integer-order and constant-order fractional partial differential equations.

This dissertation …


Controlling Properties Of Hybrid Materials: Leaching Kinetics And Electronic Structure, Anna Berseneva Aug 2024

Controlling Properties Of Hybrid Materials: Leaching Kinetics And Electronic Structure, Anna Berseneva

Theses and Dissertations

Hybrid materials are a unique class of materials that merge the properties of organic and inorganic building blocks. These materials are at the frontier of material science due to their wide modularity and applicability in numerous fields, ranging from catalysis to nuclear waste treatment. Unprecedented tunability of physical properties via changes in organic, inorganic moieties and their connectivity, enables for hybrid materials to address current challenges in the materials’ applications improving energy landscape.

The presented work consists of six chapters where the synthesis and design of new hybrid materials, fundamental understanding of electronic behavior and its modulation in organic-inorganic materials, …


Advances In Chalcogenide Crystal Growth, Anna Berseneva Aug 2024

Advances In Chalcogenide Crystal Growth, Anna Berseneva

Theses and Dissertations

Chalcogenides are the cornerstone of the semiconductor and thermoelectric industries and are up-and-coming materials for superconductors, catalysis, and battery applications. Challenges in the synthesis of those materials emerge from the chalcogen’s volatility and the tendencies of chalcogenide to react with even trace quantities of oxygen. Nonetheless, many techniques have been applied to the growth of chalcogenide single crystals, which are convenient for structure determinations and intrinsic property measurements. This dissertation will detail synthetic strategies applied to the crystal growth of novel chalcogenide materials via molten flux preparation (Chapters 2, 4, and 5), hydrothermal synthesis (Chapter 1 and 3), and single-crystal-to-single …


Deconvolving Provenance Signatures Of Pliocene-Pleistocene Coastal Loess Deposits Along The Atlantic Margin Of Argentina, Will Robert Quanrud Aug 2024

Deconvolving Provenance Signatures Of Pliocene-Pleistocene Coastal Loess Deposits Along The Atlantic Margin Of Argentina, Will Robert Quanrud

Theses and Dissertations

Dust derived from southern South America provides critical nutrients for autotropic marine biota in the South Atlantic Ocean, such that fluxes of wind-blown sediment may ultimately affect the concentration of atmospheric CO2. Expansive sand, silt, and loess deposits are exposed in Central Argentina, recording millions of years of eolian processes; however, the provenance and transport pathways of this dust remains unclear. Coastal loess deposits ranging in age from Pliocene to upper Pleistocene are present along the Atlantic margin of Argentina and provide information on sediment transport pathways for the last 4 million years. Nine samples of loess were collected and …


Macro–Micro-Coupled Simulations Of Bead–Spring Breaking-Reforming Networks, Andrei Medved Aug 2024

Macro–Micro-Coupled Simulations Of Bead–Spring Breaking-Reforming Networks, Andrei Medved

Theses and Dissertations

In this work we investigate the dynamic behavior of bead-spring polymer solutions in viscoelastic fluids, which are essential in industries like materials science, biotechnology, and pharmaceuticals. The study leverages GPU-accelerated simulations and detailed modeling of polymer chain dynamics at the mesoscale, which enables efficient analysis of intricate fluid behaviors and the microscale dynamics of polymer chains. Additionally, the research examines the breaking-reforming dynamics of polymer chains, crucial for understanding phenomena such as shear thinning and thickening. The findings have broad applications, from improving inkjet printing and 3D printing technologies to developing new drug delivery systems and biocompatible materials. This work …


Bayesian Methods In Analyzing The Diagnostic Accuracy\\ For Ordinal Ratings, Yun Yang Aug 2024

Bayesian Methods In Analyzing The Diagnostic Accuracy\\ For Ordinal Ratings, Yun Yang

Theses and Dissertations

This dissertation focuses on ordinal classification ratings, which are commonly used in medical practice to assess the severity of a disease or condition. For example, a group of radiologists rate a set of mammograms and assign BI-RADS (Breast Imaging Reporting Data System) score for each mammogram. A Bayesian probit hierarchical model is first proposed to analyze this type of data. It links the ordinal ratings with both rater diagnostic skills and patient latent disease severity. Each rater diagnostic skills are quantified with two parameters, diagnostic bias and diagnostic magnifier. Patient latent disease severity is assumed to follow a different normal …


Object Classification, Detection And Tracking In Challenging Underwater Environment, Md Modasshir Aug 2024

Object Classification, Detection And Tracking In Challenging Underwater Environment, Md Modasshir

Theses and Dissertations

The main contributions of this thesis is the applicability and architectural designs of deep learning algorithms in underwater imagery. In recent times, deep learning techniques for object classification and detection have achieved exceptional levels of accuracy that surpass human capabilities. However, the effectiveness of these techniques in underwater environments has not been thoroughly researched. This thesis delves into various research areas related to underwater environments, such as object classification, detection, semantic segmentation, pose regression, and semi-supervised retraining of detection models.

The first part of the thesis studies image classification and detection. Image classification is a fundamental process that involves assigning …


Generalizations Of The Graham-Pollak Tree Theorem, Gabrielle Anne Tauscheck Aug 2024

Generalizations Of The Graham-Pollak Tree Theorem, Gabrielle Anne Tauscheck

Theses and Dissertations

Graham and Pollak showed in 1971 that the determinant of a tree’s distance matrix depends only on its number of vertices, and, in particular, it is always nonzero. This dissertation will generalize their result via two different directions: Steiner distance k-matrices and distance critical graphs. The Steiner distance of a collection of k vertices in a graph is the fewest number of edges in any connected subgraph containing those vertices; for k = 2, this reduces to the ordinary definition of graphical distance. Here, we show that the hyperdeterminant of the Steiner distance k-matrix is always zero if …


Representation Dimensions Of Algebraic Tori And Symmetric Ranks Of G-Lattices, Jason Bailey Heath Aug 2024

Representation Dimensions Of Algebraic Tori And Symmetric Ranks Of G-Lattices, Jason Bailey Heath

Theses and Dissertations

Algebraic tori over a field k are special examples of affine group schemes over k, such as the multiplicative group of the field or the unit circle. Any algebraic torus can be embedded into the group of invertible n x n matrices with entries in k for some n, and the smallest such n is called the representation dimension of that torus. Representation dimensions of algebraic tori can be studied via symmetric ranks of G-lattices. A G-lattice L is a group isomorphic to the additive group Zn for some n, along with an action …


Metal-Organic Frameworks For Global Environmental Challenges, Kyoungchul Park Aug 2024

Metal-Organic Frameworks For Global Environmental Challenges, Kyoungchul Park

Theses and Dissertations

Over the past few decades, there has been a demand for improving nuclear waste administration due to a significant increase in the utilization of nuclear energy. The driving force for proper nuclear waste disposal is evident when considering past nuclear catastrophes—such as Chernobyl and Fukushima—where radionuclide contamination of large bodies of water sparked public concern. In order to manage such radioactive species, the emerging areas of radionuclide sequestration, storage, separation, and sensing must be addressed in the upcoming years. This dissertation presents a potential candidate for addressing these challenges, called metal-organic frameworks (MOFs). Due to their porosity, high surface area, …


Learning And Planning In Stochastic Interactive Environments With The Presence Of Sparse Dependence Structures, Zihao Deng Aug 2024

Learning And Planning In Stochastic Interactive Environments With The Presence Of Sparse Dependence Structures, Zihao Deng

McKelvey School of Engineering Graduate Student Theses & Dissertations

When interacting with an environment, an agent would want to make decisions on the fly based on the input of the dynamically changing environmental factors, so as to maximize the rewards or minimize the risks. In order to achieve that, one would want to learn the dynamics of the environment and employ efficient planning based on what has been learned about the environment. However, when the environment is large and convoluted, the planning and learning algorithms can easily become computationally intractable in general. In this thesis, we first quantitatively show that this type of problems is indeed hard to solve …


Role Of Vegfa In Intervertebral Disc Pathoanatomy And Low Back Pain, Ryan Potter Aug 2024

Role Of Vegfa In Intervertebral Disc Pathoanatomy And Low Back Pain, Ryan Potter

McKelvey School of Engineering Graduate Student Theses & Dissertations

Chronic low back pain (LBP) affects more than 80% of Americans and causes significant disability and staggering public health costs. Despite this astonishing prevalence, there are currently no disease modifying therapies. Intervertebral disc (IVD) degeneration accounts for a considerable proportion of LBP, but the precise mechanisms driving the painful pathoanatomy are not understood. The degenerating IVD exhibits a complex array of inflammatory and physiologic changes, and many are associated with the presentation of LBP. For example, the presence of nerves and blood vessels in degenerate IVDs have been identified in patients and animals presenting with LBP symptoms. However, no studies …


Development Of A Balloon Mission To Test Flight A Novel Mini-Dilution Refrigerator And A Tes Gamma-Ray Detector Array, And New Measurement Of The Spin Of The Black Hole Cygnus X-1, Md. Arman Hossen Aug 2024

Development Of A Balloon Mission To Test Flight A Novel Mini-Dilution Refrigerator And A Tes Gamma-Ray Detector Array, And New Measurement Of The Spin Of The Black Hole Cygnus X-1, Md. Arman Hossen

Arts & Sciences Graduate Student Theses and Dissertations

Transition-edge sensor (TES) detectors have become increasingly common in X-ray and gamma-ray astrophysics due to their high resolving power and feasibility of fabricating thousands of pixels within a compact area. In the framework of my thesis, I have tested a 32-pixel microwave multiplexed TES detector array, a smaller version of the SLEDGEHAMMER (Spectrometer to Leverage Extensive Development of Gamma-ray TESs for Huge Arrays using Microwave Multiplexed Enabled Readout) gamma-ray detector developed by NIST to perform X-ray and gamma-ray observation on a balloon mission known as DR-TES. DR-TES is scheduled to be launched from Fort Sumner, New Mexico, in the fall …


Sustainable Transportation: Transforming Utah Through Community Action, Isabella Erwin, Kendall Becker, Patrick A. Singleton, Scott Hotaling Aug 2024

Sustainable Transportation: Transforming Utah Through Community Action, Isabella Erwin, Kendall Becker, Patrick A. Singleton, Scott Hotaling

All Current Publications

Transportation in the United States accounts for 4% of global greenhouse gas emissions. Over half of these emissions come from on-road vehicles. Nationwide, Utah has the third highest rate of car ownership, and the resulting air pollution from on-road vehicles has significant implications for the climate and public health. This fact sheet provides information on how Utah’s government and other entities are working to expand modes of transport that minimize harm to communities and the environment.


Analysis Of The Effect Of Vaccination, Efficient Surveillance And Treatment On The Transmission Dynamics Of Cholera, Loyinmi Adedapo Chris, Ajala Adebisi Shukurat, Alani L. Ijaola Aug 2024

Analysis Of The Effect Of Vaccination, Efficient Surveillance And Treatment On The Transmission Dynamics Of Cholera, Loyinmi Adedapo Chris, Ajala Adebisi Shukurat, Alani L. Ijaola

Al-Bahir

In this study, we presented a modified SIR-SI model to investigate the dynamics and potential controls for cholera transmission, with an incident rate equipped with a saturation factor to investigate the combined impact of three vital measures which include effective surveillance, vaccination campaign and proper treatment in case severity. We established among other things, the qualitative analysis of the model to validate the results. Furthermore, the reproduction number (R0) was found to be less than unity (1), through the stability analysis. Additionally, finite different scheme was utilized in solving the differential equations of the model. MATLAB software was used for …


Estimating Post-Fire Flood Infrastructure Clogging And Overtopping Hazards, Ariane Jong-Levinger, Douglas Houston, Brett F. Sanders Aug 2024

Estimating Post-Fire Flood Infrastructure Clogging And Overtopping Hazards, Ariane Jong-Levinger, Douglas Houston, Brett F. Sanders

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Cycles of wildfire and rainfall produce sediment-laden floods that pose a hazard to development and may clog or overtop protective infrastructure, including debris basins and flood channels. The compound, post-fire flood hazards associated with infrastructure overtopping and clogging are challenging to estimate due to the need to account for interactions between sequences of wildfire and storm events and their impact on flood control infrastructure over time. Here we present data sources and calibration methods to estimate infrastructure clogging and channel overtopping hazards on a catchment-by-catchment basis using the Post-Fire Flood Hazard Model (PF2HazMo), a stochastic modeling approach that utilizes continuous …


Time-Transgressive Microbial Diversity In A Tropical Bat Guano Accumulation, Deer Cave, Mulu, Borneo, Joyce Lundberg, Donald A. Mcfarlane Aug 2024

Time-Transgressive Microbial Diversity In A Tropical Bat Guano Accumulation, Deer Cave, Mulu, Borneo, Joyce Lundberg, Donald A. Mcfarlane

International Journal of Speleology

Bat guano accumulations in caves can constitute large deposits of organic material, particularly chitin and its degradation products, that host a diverse microbiome. Previous microbiological studies have not addressed the stratified nature of these deposits in the context of the timeframe of the decomposition process. We present such data (temperature, pH, DNA sampling of eight carbon-dated strata) for a 75 cm-deep tropical guano accumulation that undergoes complete decomposition over a timescale of ~120 years. The aerobic, surface layer of freshly-fallen guano has the greatest diversity of taxa, with Bacteroidota co-dominant with Pseudomonadota, and includes many taxa unique to this …


Interventional Radiology's Exploration Into Artificial Intelligence, Raymond Nguyen Aug 2024

Interventional Radiology's Exploration Into Artificial Intelligence, Raymond Nguyen

Master's Projects and Capstones

Background: Artificial intelligence (AI) has become more prominent in our daily lives in recent years. This includes various aspects of healthcare. Interventional radiology (IR) is one of these specialties that has taken strides in understanding how AI can be leveraged for patient care. This literature review aims to understand what areas will be most impacted by AI in IR and how it will influence both the patient and interventional radiologist.

Methods: Twenty-six publications from 2019-2024 were selected from PubMed and Scopus. Publications were sourced through a combination of keywords, subject headings (MeSH terms), and citation searching.

Results: This literature review …


Molecular Rotors For Quantifying Kinetic Effects Of Stabilizing Non-Covalent Interactions, Binzhou Lin Aug 2024

Molecular Rotors For Quantifying Kinetic Effects Of Stabilizing Non-Covalent Interactions, Binzhou Lin

Theses and Dissertations

This thesis describes the development of molecular machines as analytical instruments to measure the strength of non-covalent interactions and to test hypotheses of reaction mechanisms. The first chapter is a review of molecular rotors. The second chapter presents the development of a molecular rotor that can be controlled using electrostatic interactions. Previous examples have used electrostatic interactions to slow down or inhibit molecular motion. Our system is activated and sped up using electrostatic interactions. The third and fourth chapters describe the application of molecular rotors designed to experimentally measure the strength and stability trends for non-covalent pnictogen and chalcogen interactions. …


Re: Comment Letter For The Butte Priority Soils Operable Unit (Bpsou) Diggings East 60% Remedial Design Package Submittal (Dated April 23, 2024), Emma Rott Aug 2024

Re: Comment Letter For The Butte Priority Soils Operable Unit (Bpsou) Diggings East 60% Remedial Design Package Submittal (Dated April 23, 2024), Emma Rott

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Mechanism Of Iron-Catalyzed Oxidative Α-Amination Of Ketones With Sulfonamides, Gloria M. Parrales, Nina C. Hollin, Fubin Song, Yangyang Lyu, Anne-Marie O. Martin, Alexandra E. Strom Aug 2024

Mechanism Of Iron-Catalyzed Oxidative Α-Amination Of Ketones With Sulfonamides, Gloria M. Parrales, Nina C. Hollin, Fubin Song, Yangyang Lyu, Anne-Marie O. Martin, Alexandra E. Strom

Chemistry: Faculty Publications

We report the mechanism of the iron-catalyzed oxidative α-amination of ketones with sulfonamides. Using linear free energy relationships, competition experiments, and identification of reaction intermediates, we have found that the mechanism of this reaction proceeds through rate-limiting electron transfer to 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) from an iron enolate in the process of forming an α-DDQ adduct. The adduct then serves as the electrophile for substitution with sulfonamide nucleophiles, accelerated by iron and additional DDQ. This mechanistic study rules out formation of an α-carbocation intermediate and purely radical mechanistic hypotheses.


One-Dimensional Cores Of Peano Continua, Shogo Starr Aug 2024

One-Dimensional Cores Of Peano Continua, Shogo Starr

Theses and Dissertations

In this paper, we define a berbering of a Peano continuum, which is the space one gets by attaching a null sequence of circles to a countable dense subset of a Peano continuum. The topology of a berbering is one that recognizes which circles are small, in the sense that any neighborhood of the original Peano continuum will entirely contain all but finitely many of the attached circles. We then show that given a berbering of any simply connected, locally simply connected Peano continuum $Y$, there exists a one-dimensional Peano continuum $X$ and a map from $X$ to the berbering …


On Parallelization Of Graph Algorithms, Performance Modelling And Autonomous 3d Printable Object Synthesis, Shams-Ul-Haq Syed Aug 2024

On Parallelization Of Graph Algorithms, Performance Modelling And Autonomous 3d Printable Object Synthesis, Shams-Ul-Haq Syed

Theses and Dissertations

The degree of hardware level parallelism offered by today’s GPU architecture makes it ideal for problem domains with massive inherent parallelism potential, fields such as computer vision, image processing, graph theory and graph computations. We have identified three problem areas for purpose of this research dissertation, under the umbrella of performance improvement by harnessing the power of GPUs for novel applications. The first area is concerned with k-vertex connectivity in graph theory, the second area deals performance evaluation using extended roofline models for GPU parallel applications and finally the third problem area is related to synthesis 3D printable objects from …