Physical Sciences and Mathematics Commons^™

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 Journal for Engineering and Pure Sciences

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

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 …

Erlang-Distributed Seir Epidemic Models With Cross-Diffusion, Victoria Chebotaeva

Theses and Dissertations

We examine the effects of cross-diffusion dynamics in epidemiological models. Using reaction-diffusion dynamics to model the spread of infectious diseases, we focus on situations in which the movement of individuals is affected by the concentration of individuals of other categories. In particular, we present a model where susceptible individuals move away from large concentrations of infected and infectious individuals.

Our results show that accounting for this cross-diffusion dynamics leads to a noticeable effect on epidemic dynamics. It is noteworthy that this leads to a delay in the onset of epidemics and an increase in the total number of people infected. …

Global Well-Posedness Of Nonlocal Differential Equations Arising From Traffic Flow, Thomas Joseph Hamori

Theses and Dissertations

Macroscopic traffic flow models describe the evolution of a function ρ(t, x), which represents the traffic density at time t and location x according to a differential equation (typically a conservation law). Numerous models have been introduced over the years which capture the phenomenon of shock formation in which the solution develops a discontinuity. This presents difficulties from the standpoint of mathematical analysis, necessitating the consideration of weak solutions. At the same time, this undesirable mathematical behavior corresponds to unsafe driving conditions on real roadways, in which the heaviness of traffic may vary abruptly and dramatically. This thesis introduces and …

Assessing Multi-Annual Phytoplankton Community Compositions And Biomass Across Tidal Creek And Open Water Estuarine Habitats In South Carolina, Shannon Elizabeth Powers

Theses and Dissertations

The urbanization of coastal environments in recent decades has caused an accelerating increase in nutrient-rich runoff from the landscape. The presence of these excess nutrients in the aquatic environment can result in degradation of water quality and harmful algal blooms. In South Carolina (SC), coastal development continues to threaten the resiliency of salt marsh estuaries, especially in combination with other stressors like climate change and sea level rise. Estuaries are important nurseries and habitats for fisheries and ecotourism. The South Carolina Estuarine and Coastal Assessment Program (SCECAP) is an ongoing monitoring program that assesses the habitat condition along the coast …

New Techniques For Studying Ocean Eddy Dynamics In The Arabian Sea And The Gulf Of Mexico, Paul Andrew Ernst

Theses and Dissertations

Coherent vortices known as eddies are ubiquitous throughout the world’s oceans and are responsible for modulating regional climates via the transfer of heat, momentum, and salt. Two regions where eddies are particularly prominent are the Arabian Sea (AS) and the Gulf of Mexico (GoM). This dissertation advances the study of eddies in these regions by developing and employing new techniques in conjunction with remotely sensed data and high-resolution ocean models. These models focus particularly on lesser-studied eddy components at the subsurface and the submesoscale (below 25 km in radius).

The first component of this dissertation focuses on the Lakshadweep High …

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 …

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.

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 …

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.

Automated Data-Flow Optimization For Digital Signal Processors, Madushan Thilina Abeysinghe

Theses and Dissertations

Digital signal processors (DSP), which are characterized by statically-scheduled Very-Long Instruction Word architectures and software-defined scratchpad memory, are currently the go-to processor type for low-power embedded vision systems, as exemplified by the DSP processors integrated into systems-on-chips from NVIDIA, Samsung, Qualcomm, Apple, and Texas Instruments. DSPs achieve performance by statically scheduling workloads, both in terms of data movement and instructions. We developed a method for scheduling buffer transactions across a data flow graph using data-driven performance models, yielding a 25% average reduction in execution time and a reduction of up to 85% DRAM utilization for randomly-generated data flow graphs. We …

Electronic Structure Investigation Of Photoswitch-Embedded Organic Frameworks And External Electric Field Effects On Carbon Dioxide, Austin Hill

Theses and Dissertations

Metal- and Covalent-Organic Frameworks (MOFs and COFs, respectively) are chemically versatile systems that have diverse applications, ranging from drug delivery to energy storage. This versatility is due to the highly tunable nature of organic frameworks, which utilize metal clusters, chemically diverse metals, and organic ligands. Researchers have recently demonstrated how MOFs and COFs can be remotely tuned through the use of photochromic organic linkers and light (Martin, et al., 2022). The implications of these findings are significant and have numerous applications, primarily in optical switching and energy storage. However, the photochromic mechanism within the organic framework must be investigated, which …

Investigating Arctic Ocean Freshwater Content And Circulation In A Changing Climate, Emma Louise Hoffman

Theses and Dissertations

The Arctic Ocean is unique among the world’s oceans, characterized by its cold temperatures, salinity-driven vertical structure, and shallow shelf seas. It has warmed intensely since the 1980s at rates exceeding the global average. This Arctic Amplification drives variability in sea ice and salinity, affecting local circulation and exchange with other basins, leading to global changes in oceanic and atmospheric circulation and the biosphere. This thesis explores changing dynamics in the Arctic Ocean, in particular connecting modeled changes in liquid freshwater content (FWC) and its pathways with major ocean circulation patterns, atmospheric drivers, and large-scale climatic changes.

This research combines …

Statistical Inference Based On Elliptically Symmetric Distributions For Directional Data, Zehao Yu

Theses and Dissertations

Directional data arise in many scientific fields such as meteorology, oceanography, geology, zoology, and biomechanics. Geometrically, directional data lie in a spherical space. Although not in a spherical space, compositional data, such as microbiome data, can be mapped from a simplex to a spherical space via the component-wise square-root transformation. Other examples where compositional data emerge as a subject of interest include compositions of minerals in rocks, compositions of chemical mixtures, investment portfolios, and demographic composition of a population. This dissertation aims to develop inference procedures for analyzing directional data in general initially, with later focus shifted to the transformed …

Human-Human Vs Human-Ai Therapy: An Empirical Study, Mohammad Amin Kuhail, Nazik Alturki, Justin Thomas, Amal K. Alkhalifa, Amal Alshardan

All Works

In many nations, demand for mental health services currently outstrips supply, especially in the area of talk-based psychological interventions. Within this context, chatbots (software applications designed to simulate conversations with human users) are increasingly explored as potential adjuncts to traditional mental healthcare service delivery with a view to improving accessibility and reducing waiting times. However, the effectiveness and acceptability of such chatbots remains under-researched. This study evaluates mental health professionals’ perceptions of Pi, a relational Artificial Intelligence (AI) chatbot, in the early stages of the psychotherapeutic process (problem exploration). We asked 63 therapists to assess therapy transcripts between a human …

Unraveling The Structure And Star Formation History Of Polar Ring Galaxies, Kyle Lackey

Theses and Dissertations

Polar ring galaxies (PRGs) are a fascinating subgroup of early-type galaxies (ETGs) consisting of a central host galaxy - typically E/S0 - surrounded by a ring of gas, dust and stars orbitting perpedicular to the major axis of that host. In order to estimate physical properties and origins of five such objects taken from Whitmore's 1990 PRC catalog, we conduct a photometric study in optical and infrared wavebands. Data are taken from SDSS, GMOS-S, HST-WFPC2, and SST-IRAC. Each object was decomposed into a host galaxy bulge, host galaxy disk, and polar ring, and each component was fit with a Sersic …

Molecular And Hybrid Catalysts For Selective Hydrodeoxygenation Of Lignin Model Compounds, Jacob G. Tillou

Theses and Dissertations

Lignin is a highly aromatic, branched polymer and could be utilized as a renewable source of liquid fuel. The advent of “lignin-first” depolymerization processes have allowed for the high-yield isolation of oxygenated aromatic monomers from lignin. These oxygenated aromatic compounds are lower in energy and stability than their deoxygenated counterparts. Selective deoxygenation of these compounds would result in stable, higher value liquid fuels. Using molecular catalysts, selective deoxygenation, or hydrodeoxygenation (HDO), of lignin-derived compounds in the presence of hydrogen is possible.

Immobilization of these molecular catalysts on metal oxide surfaces eliminates the possibility of bimolecular decomposition and allows for easier …

Exiting Inflation With A Smooth Scale Factor, Harry Oslislo

Theses and Dissertations

The expectation that the physical expansion of space occurs smoothly may be expressed mathematically as a requirement for continuity in the time derivative of the metric scale factor of the Friedmann–Robertson–Walker cosmology. We explore the consequences of imposing such a smoothness requirement, examining the forms of possible interpolating functions between the end of inflation and subsequent radiation- or matter-dominated eras, using a straightforward geometric model of the interpolating behavior. We quantify the magnitude of the cusp found in a direct transition from the end of slow roll inflation to the subsequent era, analyze the validity several smooth interpolator candidates, and …

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. …

Impaired Waters: New Treatments And Improved Methods For Pfas And Algae Toxins, Alexandria Forster

Theses and Dissertations

Per- and polyfluoroalkyl substances (PFAS) are high-profile environmental contaminants, many having long persistence in the environment and widespread presence in humans and wildlife. Following phase-out of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) in North America and restrictions in Europe, PFAS replacements are now widely found in the environment. While liquid chromatography (LC)-mass spectrometry (MS) is typically used for measurement, much of the PFAS is missed. To more comprehensively capture organic fluorine, we developed sensitive and robust methods using activated carbon adsorption, solid phase extraction, and combustion ion chromatography (CIC) to measure total organic fluorine (TOF) in industrial wastewaters, river …

Scene Text Detection And Recognition Via Discriminative Representation, Liang Zhao

Theses and Dissertations

Scene texts refer to arbitrary text presented in an image captured by a camera in the real world. The tasks of scene text detection and recognition from complex images play a crucial role in computer vision, with potential applications in scene understanding, information retrieval, robotics, autonomous driving, etc. Despite the notable progress made by existing deep-learning methods, achieving accurate text detection and recognition remains challenging for robust real-world applications. The challenges in scene text detection and recognition stem from: 1) diverse text shapes, fonts, colors, styles, layouts, etc.; 2) countless combinations of characters with unfixed attributes for complete detection, coupled …

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 …

Hypogenic Caves Of Syracuse Area, Sicily (Italy): Geomorphological Evidence Of Co2 Degassing, Fresh-Salt Water Mixing, And Late Condensation Corrosion, Philippe Audra, Jean-Yves Bigot, Didier Cailhol, Pierre Camps, Ilenia M. D'Angeli, Hai Cheng, R. Lawrence Edwards, Fernando Gàzquez-Sanchez, Gabriella Koltai, Giuliana Madonia, Jean-Claude Nobécourt, Marjan Temovski, Marco Vattano, Jo De Waele

International Journal of Speleology

Many caves in Sicily have been shown to have a sulfuric acid or other hypogenic origin. We studied three caves (Palombara, Scrivilleri, Monello) near Syracuse (eastern Sicily), in an area that was strongly uplifted and faulted, creating multiple Pleistocene marine terraces. Mineralogy, stable isotopes and dating methods (paleomagnetism, U/Th) were used to characterize cave sediments, some of which were related to the initial hypogenic phase (Fe and Mn oxides, calcite spar), others were introduced by surface runoff later. Many other sediments are the result of in situ weathering, such as lime sands produced by condensation-corrosion processes on the calcarenite walls. …

Wildcat Hills Rare Plant Survey Final Report, Steven B. Rolfsmeier

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

This survey report summarizes fifteen days of field work in eleven sites scattered across the Wildcat Ridge that were completed between May and August of 1996. Forty-five occurrences of 15 plant species on the Nebraska Natural Heritage element list were found. Ten tracts of high quality (or otherwise noteworthy) native communities were identified. Included in the report are site descriptions and element occurrences.

Deep Learning For Source Localization In A Laboratory Tank, Corey Emerson Dobbs

Theses and Dissertations

Deep learning has been applied to underwater acoustics problems in many forms. One difficulty in applying deep learning techniques to ocean acoustics is the spatially and temporally varying environmental properties. Another challenge is the lack of labeled data for training large networks. The overall goal of this work is to develop deep learning approaches for source localization that can be adaptable to different conditions. In this work, a convolutional neural network was trained on acoustic data measured in a water tank, while the water was at room temperature, to predict source-receiver range. Tests were done to ascertain ideal quantities of …

Wind-Carved Wonders: An Aerial Study Of Yardangs In The Puna, Argentina Using Drone And Satellite Imagery, Derek Gordon Ashliman

Theses and Dissertations

Yardangs, elongated landforms sculpted by wind erosion, are prominent features in the Campo de Piedra Pomez (CPP) region of the Puna-Altiplano Plateau, Argentina. This study explores their formation and evolution through the examination of a 6 km by 0.5 km area captured in 2019 and a 5 km by 0.5 km area in 2024. High-resolution drone imagery and satellite data were employed to classify and quantify yardangs, gravel, and underlying bedrock across a vast study area. The research reveals a variation in yardang distribution and morphology from northwest (windward) to southeast (leeward), noting a significant decrease in yardang and bedrock …

Re: Comment Letter For The Butte Priority Soils Operable Unit (Bpsou) Draft Final Annual Operations And Maintenance Report Butte Treatment Lagoon System – 2023 (Dated May 28, 2024), Emma Rott

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

2024 August 15 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Weekly Drought Summaries

No abstract provided.

Dynamics Of Dissolved And Particulate Trace Metals In A Snowmelt-Dominated Stream, Provo River, Utah, Usa, Kendra Louise Caskey

Theses and Dissertations

Trace element concentrations vary substantially during snowmelt runoff, with changes in the dissolved versus particulate fractions potentially impacting their movement at the catchment scale. To investigate trace element behavior in a snowmelt dominated stream, we measured concentrations in different size fractions in the Provo River (northern Utah, USA). We sampled the river at three locations during water years 2016-2018 and 2021-2023 for trace metal and major ion concentrations. During the final year, we collected three fractions (unfiltered, <0.45 µm filtered, and <0.22 µm filtered) for trace metal chemistry and calculated the particulate concentration as the difference between the unfiltered and 0.45 µm fraction. Stream measurements included pH, discharge, turbidity, and fluorescent dissolved organic matter (fDOM). We also sampled water sources (soil water, ephemeral streams, and snowpack) to compare trace metal concentrations across the watershed with the stream. Trace metal (Al, Be, Fe, Pb) and rare earth element (REE +Y) concentrations had the highest particulate and dissolved concentrations during snowmelt runoff. In contrast, major cations were primarily found in the dissolved fraction with lowest concentrations during snowmelt runoff. Major cation and particulate metal concentrations increased from upstream to downstream. The increased trace metal and REE + Y concentrations during snowmelt relative to baseflow may be explained by increased discharge and associated increased turbidity and fDOM. A comparison with water sources suggests that dissolved and particulate trace metals in the stream are sourced from flushed soil water, as trace metal transport through the watershed is facilitated by suspended sediment and dissolved organic matter. For most of the trace metals and REE +Y, concentrations were similar in the <0.45 µm and <0.22 µm fractions. Yet Al tended to have higher concentrations in the <0.45 µm fraction, suggesting a colloidal form of Al between 0.22 µm and 0.45 µm may exist. Differences from upstream to downstream may be related to changes in pH, from ~7 at the upper site to ~8 at the lower sites, which would change sorption capacity, saturation indices, or speciation. Our study demonstrates that trace metal concentrations are variable during snowmelt as the metals interact with suspended particles or dissolved organic matter and are influenced by changing water chemistry, with implications for understanding water quality impairments in snowmelt-dominated streams.

Climate Change And Its Impact On Health: A Global Collaborative Learning Model, Harriet Okatch, Patricia Remshifski, Anita Fennessey, Haley Campbell, Sivia Barnoy, Jason Friedman, Stephen Kern, Rosemary Frasso, Cecilia Sorensen, Tami Bar-Shalita, Louis Hunter

College of Population Health Faculty Papers

To address the health effects of climate change, leaders in healthcare have called for action to integrate climate adaptation and mitigation into training programs for health professionals. However, current educators may not possess sufficient climate literacy and the expertise to effectively include such content in their respective healthcare curricula. We, an international and interprofessional partnership, collaborated with experts to develop and deploy curriculum to increase health educators' and graduate health profession students' knowledge and competencies on climate change. In a tri-step process, the first phase included recruiting interested faculty members from two institutions and varying health professions. In phase two, …