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Full-Text Articles in Physical Sciences and Mathematics

Chemically Modified Cyclofructans For Sub/Supercritical Fluid Chromatography And Hydrophilic Interaction Liquid Chromatography, Sepideh Khaki Firooz Aug 2022

Chemically Modified Cyclofructans For Sub/Supercritical Fluid Chromatography And Hydrophilic Interaction Liquid Chromatography, Sepideh Khaki Firooz

Chemistry & Biochemistry Theses

Given the importance of supercritical fluid chromatography, several works focused on the application use different SFC stationary phases. In this work, two new derivatized cyclofructan bonded phases with superficially porous particles are introduced in SFC. Sulfonic acid and benzoic acid groups were covalently linked to the cyclofructan molecule to make them polar and hydrophilic. These derivatives were then bonded to superficially porous particles for high-efficiency separations. This work also shows the effect of adding a small amount of water to the modified mobile phases in SFC. Traces of water in the co-solvent enhances the peak symmetry and efficiency of these …


Self-Assembling Peptides: From Fundamental Design To Therapeutic Applications, Weike Chen Aug 2022

Self-Assembling Peptides: From Fundamental Design To Therapeutic Applications, Weike Chen

Chemistry & Biochemistry Dissertations

Supramolecular peptide-based biomaterials have attracted much attention from researchers in various science and engineering fields because of the ease of synthesis and precise control over structures and physicochemical properties on multiple length levels. Self-assembled peptides have shown great potential as functional biomaterials for both diagnosis and treatment of various diseases. In Chapter 1, I will introduce several self-assembled peptide systems in terms of molecular design, structure characterization, and their biological applications. In particular, I will discuss new peptide self-assemblies with trigger-responsive properties for targeted molecular imaging and therapy. In Chapter 2, I will focus on peptide self-assembly that can target …


Age, Provenance And Tectonic Implications Of Late Paleozoic Volcanic Tuffs In Southwest Laurentia, Hepeng Tian Aug 2022

Age, Provenance And Tectonic Implications Of Late Paleozoic Volcanic Tuffs In Southwest Laurentia, Hepeng Tian

Earth & Environmental Sciences Dissertations

Assembly of the supercontinent Pangea is among the most important tectonic events in late Paleozoic Earth history. The diachronous Laurentia-Gondwana collision destroyed the intervening subduction zone(s) of the Rheic oceanic plate, ultimately leading to subduction of the Paleo-Pacific oceanic plate beneath western Pangea. However, details about the timing, nature, and geochemical signatures of the two arc systems during the transition from Rheic oceanic plate to Paleo-Pacific oceanic plate subduction are poorly understood. This lack of understanding, in part, reflects the fact that arc magmatic products (esp. granitic rocks) related to the Rheic ocean subduction are largely obscured by those related …


Lncrteo6 (Ln= La, Pr, Nd) Octahedral Distortions And Optical Characterization, Katheryn R. Cruz Aug 2022

Lncrteo6 (Ln= La, Pr, Nd) Octahedral Distortions And Optical Characterization, Katheryn R. Cruz

Chemistry & Biochemistry Theses

LnCrTeO6 (La, Pr, Nd) compounds are suspected to appear as vibrant blue-green colored materials. LnCrTeO6 (La, Pr, Nd) were synthesized to analyze the local coordination environments of Ln3+, Cr3+, and Te6+ cations. Structural characterization was performed using X-ray diffraction (XRD) and optical properties were examined using diffuse reflectance spectroscopy (DRS). DRS data was further processed using the Kubelka-Munk function and a Tauc plot was generated to determine the direct and indirect band gap of these semiconducting materials. The superstructure peak corresponding to the (101) plane displayed relatively weak intensities in all samples and decreased in intensity from La to Nd. …


Nanopetrophysical Characterization Of The Upper Mancos Shale In The San Juan Basin, New Mexico, U.S.A., Ann Kiat Gan Aug 2022

Nanopetrophysical Characterization Of The Upper Mancos Shale In The San Juan Basin, New Mexico, U.S.A., Ann Kiat Gan

Earth & Environmental Sciences Theses

The San Juan Basin is no stranger to oil and gas production and the Mancos Shale is one of the formations of the basin that had been producing petroleum since the early 1920’s as conventional, and recently as, unconventional resources. Due to the economic significance of shale oil and gas production, oil and gas companies have a strong motivation to understand the petrophysical property measurements of shale reservoirs, in this case, the Upper Mancos Shale, both in the laboratory and in the subsurface. By understanding shale petrophysics, such as total organic carbon, mineral composition, wettability, porosity, permeability, pore connectivity for …


Stimuli-Responsive Peptide Self-Assembly For Therapeutic Delivery, Su Yang Aug 2022

Stimuli-Responsive Peptide Self-Assembly For Therapeutic Delivery, Su Yang

Chemistry & Biochemistry Dissertations

Peptide self-assembly offers an effective method to generate supramolecular nanomaterials with much higher stability than traditional monomeric peptides. The materials exhibit well-organized hierarchical structures and high resistance toward proteolysis and have been utilized extensively in various biomedical applications. Furthermore, due to the prevalence of non-covalent interactions, these structures are highly dynamic. The dynamic nature is beneficial for the design and synthesis of smart, trigger-responsive peptide selfassembly under specific stimulus, in particular various stimuli associated with disease conditions. In Chapter 1, I will introduce different types of peptide building blocks used for the construction of peptide self-assembly. I will further discuss …


A Comparison Of Methods Used For The Elimination Of Organics From Soil Prior To Analysis By Ftir-Atr And Sem-Eds, Argeliz Pomales Aug 2022

A Comparison Of Methods Used For The Elimination Of Organics From Soil Prior To Analysis By Ftir-Atr And Sem-Eds, Argeliz Pomales

Student Theses

This project suggests improvements to the treatment methods utilized for the sample preparation and evaluation of minerals in soil samples encountered in forensic science casework and research. The evaluation of pre-treated and post-treated soil samples were performed using Fourier-Transform Infrared Spectroscopy with Attenuated Total Reflection (FTIR-ATR) and Scanning Electron Microscopy-Energy Dispersive Spectroscopy (SEM-EDS). Because soil samples contain a significant amount of organic matter and water which interfere with examination of these minerals while using these instruments, pretreatment methods are necessary to isolate the mineral fraction for examination and analysis.

Soil samples were first sieved with various size stainless steel mesh …


Inducible Dna Interstrand Cross-Linking Agents: Design, Synthesis, Mechanism, And Biomedical Applications, Muhammad Asad Uz Zaman Aug 2022

Inducible Dna Interstrand Cross-Linking Agents: Design, Synthesis, Mechanism, And Biomedical Applications, Muhammad Asad Uz Zaman

Theses and Dissertations

DNA is the carrier of genetic information, making its chemical reactivity and function extremelyimportant. DNA interstrand cross-links (ICL) leads to covalent bind of two strands, which prevents the separation of double helix. DNA ICLs are the sources of the cytotoxicity of antitumor and anticancer agents. This thesis focuses on investigating the reactivity of a varieties of aromatic compounds towards DNA. Some of these molecules can be activated by photo irradiation to induce DNA ICL formation via alkylation. Others undergo activation by H2O2 to release DNA cross-linking agents. We investigated the mechanism of function of these inducible DNA cross-linking agents as …


Synthesis And Processing Of Polymeric Materials For Hydrogen Storage, Dominic Adrewie Aug 2022

Synthesis And Processing Of Polymeric Materials For Hydrogen Storage, Dominic Adrewie

Theses and Dissertations

Hydrogen is one of the most promising alternatives and clean fuel sources, but it has faced several hurdles due to storage and transportation issues. Several methods have been proposed, developed, and are being improved. Key among these is the use of polymers as safe hydrogen storage media.

This work investigated the polymerization of methyl vinyl ketone using different concentrations 2,2’-Azobis(2-methylpropionitrile) as the initiator in a free radical polymerization mechanism. There was a subsequent analysis of the effect of the initiator concentration on the conversion rate and the molecular weight of the polymers produced with the help of Gel permeation chromatography. …


Effects Of Macronutrients Intake And Physical Activity On Childhood Obesity Of Hispanic Children, Prosanta Barai Aug 2022

Effects Of Macronutrients Intake And Physical Activity On Childhood Obesity Of Hispanic Children, Prosanta Barai

Theses and Dissertations

Obesity has become more ubiquitous during the past few decades, and still, its prevalence is increasing. It is in every population in the world and all regions, including rural parts of low and middle-income countries. In the USA, regardless of age, the severity of obesity is no different from the global trend. Although numerous pieces of literature are available, that tried to find answers to some pressing issues like how obesity can be controlled, but there is little to no study focused on younger children, especially the 4-6-year-old Hispanic population. Our study aimed to determine the causal path among literature …


Quantization For A Nonuniform Triadic Cantor Distribution, Asha Barua Aug 2022

Quantization For A Nonuniform Triadic Cantor Distribution, Asha Barua

Theses and Dissertations

The quantization scheme in probability theory deals with finding a best approximation of a given probability distribution by a probability distribution that is supported on finitely many points. Let P be a Borel probability measure on R such that P := 1/4 P◦ S1−1 + 1\2 PS2−1 + 1/4 PS3−1, where S1, S2 and S3 are three contractive similarity mappings such that Sj(x) = 1/5x+2(j−1)/5, for all x ∈ R. For this probability measure, in this thesis, we determine the optimal sets of n-means and the nth quantization errors for …


Assessing Intra-Urban Particulate Matter (Pm2.5) Concentrations At The Lower Rio Grande Valley (Rgv), South Texas, Usa, Using Low-Cost Sensors, Esmeralda Mendez Aug 2022

Assessing Intra-Urban Particulate Matter (Pm2.5) Concentrations At The Lower Rio Grande Valley (Rgv), South Texas, Usa, Using Low-Cost Sensors, Esmeralda Mendez

Theses and Dissertations

Rapid technological developments of novel low-cost air quality sensors enable long-term ambient monitoring in neighborhood areas. In this study, spatial and temporal trends are analyzed by localized level monitoring with low-cost sensors (TSI BlueSky Air Quality Monitor). Eleven low-cost sensors were deployed across the Lower Rio Grande Valley, South Texas region: Brownsville, Edinburg, Weslaco, and Port Isabel. 24-hour PM2.5 concentrations are correlated with PM2.5 from existing Texas Commission on Environmental Quality (TCEQ) Continuous Ambient Monitoring Stations (CAMSs) to express temporal and spatial heterogeneity from March 01, 2021, to March 31, 2022. Results indicated the deployed low-cost sensors as a better …


Thermal Convection In A Cylindrical Annulus Filled With Porous Material, Anirban Ray Aug 2022

Thermal Convection In A Cylindrical Annulus Filled With Porous Material, Anirban Ray

Theses and Dissertations

Here a study on thermal convection in a porous vertical cylindrical annulus which is heated from below is carried out. The walls are considered to be impermeable that is the velocity is 0 at the boundary walls. The cylindrical annulus is radially insulated. The governing system consists of the continuity equation, Darcy-Boussinesq equation, heat equation and the equation of state. Employing weakly non-linear approach, the basic state system and the perturbed system are derived. After obtaining the solutions to the basic state system, the pressure term in perturbed system is eliminated by taking double curl, and then eliminating the velocity, …


Could Cultures Determine The Course Of Epidemics And Explain Waves Of Covid-19?, Md Salman Rahman Aug 2022

Could Cultures Determine The Course Of Epidemics And Explain Waves Of Covid-19?, Md Salman Rahman

Theses and Dissertations

Coronavirus Disease (COVID-19), caused by the SARS-CoV-2 virus, is an infectious disease that quickly became a pandemic spreading with different patterns in each country. Travel bans, lockdowns, social distancing, and non-essential business closures caused significant economic disruptions and stalled growth worldwide in the pandemic’s first year. In almost every country, public health officials forced and/or encouraged Nonpharmaceutical Interventions (NPIs) such as contact tracing, social distancing, masks, and quarantine. Human behavioral decision-making regarding social isolation significantly impedes global success in containing the pandemic. This thesis focuses on human behaviors and cultures related to the decision-making of social isolation during the pandemic. …


Network Analysis Of Scientific Research In The Gulf Of Mexico, Juliet S. Vallejo Aug 2022

Network Analysis Of Scientific Research In The Gulf Of Mexico, Juliet S. Vallejo

Theses and Dissertations

The Gulf of Mexico ecosystem represents a significant management challenge in its 3,423-mile coastline and transnational regulatory setting, along five states from the United States, six states from Mexico, and Cuba which borders the southeastern quadrant. Providing various resources to the regional economies, the continued success of these resources depends on the collaboration among transnational participants in bringing together complementary skills and multidisciplinary approaches to producing, circulating, and utilizing scientific knowledge. Using bibliometric analysis of Gulf of Mexico-related published research over 18 years from 2000 to 2018 allows for identifying organizations, their connections, and trends in the production of scientific …


Neural Networks And Stochastic Differential Equations, Stephanie L. Flores Aug 2022

Neural Networks And Stochastic Differential Equations, Stephanie L. Flores

Theses and Dissertations

Influenced by the seminal work, “Physics Informed Neural Networks” by Raissi et al., 2017, there has been a growing interest in solving and parameter estimation of Nonlinear Partial Differential Equations (PDE) with Deep Neural networks in recent years. In fact, this has broadened the pathways and shed light on deep learning of stochastic differential equations (SDE) and stochastic PDE’s (SPDE).In this work, we intend to investigate the current approaches of solving and parameter estimation of the SDE/SPDE with deep neural networks and the possibility of extending them to obtain more accurate/stable solutions with residual systems and/or generative adversarial neural networks. …


Academic Integration And Self-Regulation Strategies In Precalculus And Calculus I, Kyle Russell Turner Aug 2022

Academic Integration And Self-Regulation Strategies In Precalculus And Calculus I, Kyle Russell Turner

Mathematics Dissertations

This case study examines the self-regulation strategies and academic integration of first-semester undergraduate students enrolled in precalculus and first-semester calculus at a large urban university in the southwestern United States. I use a sequence of interviews to examine the relationship of mathematics self-efficacy and mathematics identity on students’ use of these strategies. Five interviews occurred during the Fall 2021 semester with three precalculus and six calculus students, and I distributed initial surveys to thirteen first-semester calculus sections and five precalculus sections. To analyze the data, I integrated frameworks from Zimmerman and Pons (1986) and Wolters (1998) on the self-regulation strategies …


Developing Confidence And Interest In Teaching Relevant Mathematical Modeling Lessons, Jacy Beck Aug 2022

Developing Confidence And Interest In Teaching Relevant Mathematical Modeling Lessons, Jacy Beck

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

What is mathematical modeling and how can inservice and pre-service teachers develop the skills and competencies necessary to increase confidence and interest in teaching relevant mathematical modeling lessons? Mathematical modeling is “the process of choosing and using appropriate mathematics and statistics to analyze empirical situations, to understand them better, and to improve decisions” (CSSM, 2010, p. 72). By providing students with an opportunity to engage in relevant mathematical modeling prompts, we provide them with transferable skills and knowledge. The aim of this paper will be to provide insight into the relevance of teaching mathematical modeling, provide resources for integrating modeling …


Dynamic System Discovery With Recursive Physics-Informed Neural Networks, Jarrod Mau Aug 2022

Dynamic System Discovery With Recursive Physics-Informed Neural Networks, Jarrod Mau

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis presents a novel method, recursive Physics informed neural network, to learn the right hand side of differential equations. The neural network takes in data, then trains, and then acts as a proxy for the differential equation which can be used for modeling. We show the theoretical superiority of the recursive approach. We also use computer simulations to demonstrate the proved properties.


Syntax Exercises And Their Effect On Computational Thinking, Marina Johnson Aug 2022

Syntax Exercises And Their Effect On Computational Thinking, Marina Johnson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Abstract—Job opportunities and the need for programmers are increasing. Companies are looking for new hires who have the ability to learn how to learn, who have computational thinking skills. Student dropout rate in computer science is the highest among college majors. Educators are striving to find a way to teach efficiently and effectively the technical and the problem solving skills students need. In this paper we will be studying the effects of syntax exercises on a subject’s ability to think computationally and precisely. We tested our process on professionals and students. Half of the professionals were in the computer science …


Evaluation Of The Geothermal Potential Of The Camas Prairie, South-Central Idaho, Connor J. Smith Aug 2022

Evaluation Of The Geothermal Potential Of The Camas Prairie, South-Central Idaho, Connor J. Smith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The area studied in this thesis was assessed based on the analysis of a water sample collected from the exploratory well USU Camas-1. The water sample was characterized and compared to other water samples collected and analyzed during a previous phase of this project according to its water chemistry.

Lithologic, geophysical, and temperature logs were also used to assess the study area. The depth sensitive data was analyzed to determine the characteristics of the formation as they relate to the favorable parameters of a geothermal resource, those being permeability of the subsurface, heat, and the presence of a clay seal. …


Extensions To The Syrjala Test With Eye-Tracking Data Analysis Applications In R, Eric D. Mckinney Aug 2022

Extensions To The Syrjala Test With Eye-Tracking Data Analysis Applications In R, Eric D. Mckinney

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Eye tracking is a process for measuring the movement of an individual’s eye(s) when that individual is looking at something. Many eye-tracking technologies exist to aid in calculating and recording data associated with what a person focuses their visual attention on. For example, eye-tracking technology can record points on an image that a person is looking at. Often the question arises as to whether two people, or groups of people, are looking at the same thing(s). This dissertation presents a new way (or test) to quantify those differences while taking into consideration the randomness associated with such data. Hence, the …


The Effect Of Species Choice, Seed Mix Composition, And Microtopography On Native Plant Restoration In Great Salt Lake Wetlands, Coryna Hebert Aug 2022

The Effect Of Species Choice, Seed Mix Composition, And Microtopography On Native Plant Restoration In Great Salt Lake Wetlands, Coryna Hebert

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Wetlands are important ecosystems that improve water quality, prevent floods, and provide wildlife habitat. As such, restoring native plants that promote wetland health is a high priority for land managers. However, there are many challenges to the restoration of native plants. In our study system (Great Salt Lake wetlands), many areas are invaded by the European grass, Phragmites australis. Phragmites grows in dense stands and displaces native plants. The reduction of native plant communities in Great Salt Lake wetlands is a major concern because these ecosystems provide habitat for millions of native birds. Managers have made successful efforts to …


Joint Invariants Of Primitive Homogenous Spaces, Illia Hayes Aug 2022

Joint Invariants Of Primitive Homogenous Spaces, Illia Hayes

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Joint invariants are motivated by the study of congruence problems in Euclidean geometry, where they provide necessary and sufficient conditions for congruence. More recently joint invariants have been used in computer image recognition problems. This thesis develops new methods to compute joint invariants by developing a reduction technique, and applies the reduction to a number of important examples.


Programming Process, Patterns And Behaviors: Insights From Keystroke Analysis Of Cs1 Students, Raj Shrestha Aug 2022

Programming Process, Patterns And Behaviors: Insights From Keystroke Analysis Of Cs1 Students, Raj Shrestha

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

With all the experiences and knowledge, I take programming as granted. But learning to program is still difficult for a lot of introductory programming students. This is also one of the major reasons for a high attrition rate in CS1 courses. If instructors were able to identify struggling students then effective interventions can be taken to help them. This thesis is a research done on programming process data that can be collected non-intrusively from CS1 students when they are programming. The data and their findings can be leveraged in understanding students’ thought process, detecting patterns and identifying behaviors that could …


Using The Reshetikhin-Turaev Link Invariant Approach With Non-Semisimple Categories, Adam Robertson Aug 2022

Using The Reshetikhin-Turaev Link Invariant Approach With Non-Semisimple Categories, Adam Robertson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Invariants of knots and links are useful because they give rise to invariants of 3-manifolds. In particular, combinatorial link invariants give rise to combinatorial invariants of 3-manifolds, which are hard to come by using traditional methods from classical topology. The Reshetikhin–Turaev approach, which is based in quantum topology, develops link invariants using semisimple ribbon categories. However, a large class of algebraically interesting ribbon categories are non-semisimple and so give trivial link invariants via the Reshetikhin–Turaev method. We modify the Reshetikhin–Turaev method to make it suitable for non-semisimple ribbon categories. We discuss explicitly the following three examples: semisimple modules for the …


Comparing Fecal Dna Capture-Recapture Methods To Traditional Mark-Resight Methods For Estimating Abundance Of Mule Deer On Winter Ranges, Andi M. Stewart Aug 2022

Comparing Fecal Dna Capture-Recapture Methods To Traditional Mark-Resight Methods For Estimating Abundance Of Mule Deer On Winter Ranges, Andi M. Stewart

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Well-designed monitoring strategies are required to obtain accurate estimates of population abundance, which is important for evaluating conservation and management strategies. Obtaining abundance estimates using traditional survey methods, like aerial surveys, is not possible in all scenarios and can be expensive and risky. One survey method that has gained popularity in the last decade is fecal DNA-based capture-recapture (CMR). However, this method has not been evaluated on winter ranges or in snowy, winter conditions.

My first objective was to implement fecal DNA CMR to estimate abundance of mule deer in the Round Valley and Goodale winter survey areas in the …


Pesticide-Leaf Interactions And Their Implications For Pesticide Fate Modeling, Ashlie Kinross Aug 2022

Pesticide-Leaf Interactions And Their Implications For Pesticide Fate Modeling, Ashlie Kinross

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The work described here provides measured data to improve the understanding of the interaction between a pesticide and leaf surface after application. Two methods were developed, one using a newly introduced instrument, for the extraction of pesticides from leaves. This is required to measure the concentration of pesticide in the leaves. Using one of the developed extraction methods, measurements were made to determine how a pesticide equilibrates between a leaf and the air above it. These measurements were incorporated into a pesticide fate model that predicts how a pesticide moves through the environment after application to an agricultural field. The …


Conservation Genetics Of A Declining Bumble Bee In Western North America; The Influence Of Geography, Dispersal Limitation, And Anthopogenic Activity, Ashley T. Rohde Aug 2022

Conservation Genetics Of A Declining Bumble Bee In Western North America; The Influence Of Geography, Dispersal Limitation, And Anthopogenic Activity, Ashley T. Rohde

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Conservation biology addresses the problem of species loss by identifying species in need of protection. Conservation biology has subfields to address different aspects of biodiversity loss, including genetics and sociology. I used genetic approaches to assess the conservation status of western bumble bees, a bumble bee species of conservation concern.

The western bumble bee is a bumble bee species that ranges from Alaska to New Mexico and as far east as Wyoming and Colorado. This species is disappearing in some places. It may soon be listed as endangered in the United States and is already listed as endangered in parts …


Redefining Nba Basketball Positions Through Visualization And Mega-Cluster Analysis, Alexander L. Hedquist Aug 2022

Redefining Nba Basketball Positions Through Visualization And Mega-Cluster Analysis, Alexander L. Hedquist

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Basketball players have historically been classified based on one of five positions, namely Point Guards, Shooting Guards, Small Forwards, and Centers. While grouping players into these five categories may provide general descriptions of their perceived role, these standard positions fall short of describing players based on their true abilities and performance. This MS thesis proposes a method to group players of the National Basketball Association (NBA) from the past 20 seasons into more meaningful and specific player positions. We systematically group these players into nine distinct categories, and we draw from a vast array of visualization tools, techniques, and software …