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Full-Text Articles in Physical Sciences and Mathematics

Excitation Power Dependence Of Blinking In Copper-Indium-Sulfide Quantum Dots, Nicholas Chambers May 2023

Excitation Power Dependence Of Blinking In Copper-Indium-Sulfide Quantum Dots, Nicholas Chambers

Physics Undergraduate Honors Theses

Under continuous excitation, quantum dots exhibit random transitions between fluorescent ON states and non-fluorescent OFF states --- a phenomenon known as blinking. A physical description of the mechanism responsible for blinking that applies broadly to many types of quantum dots remains under debate. We study the blinking behavior of the non-toxic CuInS2 quantum dot, a system that has seen little investigation at the single-particle level. In particular, the optical properties of CuInS2 quantum are often improved by adding ZnS to the nanoparticles, but this addition leads to complex structural-optical property relationships that are even less understood. To probe the relationship …


Evaluating Snow And Ice Cover In Tierra Del Fuego, Argentina, Zoe Pitman May 2023

Evaluating Snow And Ice Cover In Tierra Del Fuego, Argentina, Zoe Pitman

Geosciences Undergraduate Honors Theses

Evaluating changes in snow and ice cover is an important field for studying climate change and its impacts. This evaluation is commonly done using remote sensing because of its ability to evaluate large areas. The purpose of this study is to determine the reliability of one remote sensing technology, the Moderate Resolution Imaging Spectroradiometer (MODIS), by comparing it to in-situ snow and climate data from the weather station at the Austral Center for Scientific Research (CADIC). Data was converted from daily to monthly averages and was sorted into a series of graphs to compare the two data sets. Correlations were …


Culture In Computing: The Importance Of Developing Gender-Inclusive Software, Creighton France May 2023

Culture In Computing: The Importance Of Developing Gender-Inclusive Software, Creighton France

Computer Science and Computer Engineering Undergraduate Honors Theses

The field of computing as we know it today exists because of the contributions of numerous female mathematicians, computer scientists, and programmers. While working with hardware was viewed as “a man’s job” during the mid-20th century, computing and programming was viewed as a noble and high-paying field for women to occupy. However, as time has progressed, the U.S. has seen a decrease in the number of women pursuing computer science. The idea that computing is a masculine discipline is common in the U.S. today for reasons such as male-centered marketing of electronics and gadgets, an inaccurate representation of what it …


Integration Of Computer Algebra Systems And Machine Learning In The Authoring Of The Sanyms Intelligent Tutoring System, Sam Ford May 2023

Integration Of Computer Algebra Systems And Machine Learning In The Authoring Of The Sanyms Intelligent Tutoring System, Sam Ford

Computational and Data Sciences (PhD) Dissertations

Computer-based feedback is an increasingly common tool in mathematics education. The feedback that such programs provide can range from indicating whether an answer was correct, to giving an answer or worked out solution or suggesting a similar practice problem. One type of computer-based feedback, the Intelligent Tutoring Systems (ITS), is able to provide feedback not just once per problem, but at multiple points during the process of solving a problem. Creating an ITS that gives feedback for even a narrow topic is often a time-intensive process, and machine learning is only recently being integrated into the ITS authoring process.

We …


Framing How We Think About Curves, Megan Sattler May 2023

Framing How We Think About Curves, Megan Sattler

Mathematical Sciences Undergraduate Honors Theses

A frame defines a basis at a point in R^n, and we can frame a curve by placing one at every point along it. This thesis investigates adapted framed curves in R^2 and R^3 in which they are used to provide information about how a curve twists and turns. We derive differential information from the frames that describe how they change and consequently how the curve changes. We also deduce special properties of each framing and discuss how the differential information suffices to describe the shape of curves.


Source Code Plagiarism Detection Using Jplag & Stack Overflow Data, Sudheer Yetthapu May 2023

Source Code Plagiarism Detection Using Jplag & Stack Overflow Data, Sudheer Yetthapu

Masters Theses & Specialist Projects

Advancements in computer technology and internet services have led to the availability of vast amounts of information like videos, articles, research papers, and code samples. Free online information will increase the possibility of plagiarism and collusion among students. People can commit plagiarism in both text and code [1], as tools used to detect plagiarism between texts and between codes are distinct. Traditionally plagiarism in code is detected using manual inspection, which is a tedious process and misses to compare code from previous submissions and external sources. To overcome this issue, systems that can automatically detect plagiarism in code were developed …


Methods For Preparing And Characterizing Granular Materials For Electron Yield Measurements, Tom Keaton May 2023

Methods For Preparing And Characterizing Granular Materials For Electron Yield Measurements, Tom Keaton

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

This work presents a systematic study on sample preparation methods and accuracy of electron yield (EY) measurements of highly insulating, granular materials. EY measurements of highly insulating materials, especially those with high EY, are challenging due to the effects of sample charging even for very low fluence electron probe beams. EY measurements of particulates are complicated by: (i) roughness effects from particulate size, shape, coverage, and compactness; (ii) particle adhesion; (iii) substrate contributions; and (iv) electrostatic repulsion and potential barriers from charged particles and substrates. Numerous methods were explored to rigidly affix particles on conducting substrates at varying coverages for …


Analysis On High Mass X-Ray Binary Spectral Shape Dependence On Luminosity For Ngc3310, Izabela Pavel May 2023

Analysis On High Mass X-Ray Binary Spectral Shape Dependence On Luminosity For Ngc3310, Izabela Pavel

Physics Undergraduate Honors Theses

In most normal galaxies, the most X-ray luminous sources are high-mass X-ray binaries (HMXBs), which are binary star systems that contain compact objects (black holes or neutron stars) accreting from massive (> 8M⊙) companion stars. These HMXBs are thought to have been important sources of ionizing emission within star-forming galaxies that may have contributed to the heating of the intergalatic medium (gas over large cosmic scales) in the early Universe. When studying how HMXBs contribute to interstellar medium feedback, a single spectral shape of an absorbed power-law is typically assumed to be universal. The goal of this thesis is to …


Automating The Determination Of Tight-Binding Representations For Two-Dimensional Ferroelectrics, Joseph Roll May 2023

Automating The Determination Of Tight-Binding Representations For Two-Dimensional Ferroelectrics, Joseph Roll

Physics Undergraduate Honors Theses

Two-dimensional (atomically thin) materials have been greatly explored in the last two decades since the exfoliation of graphene in 2004. Since then, many exotic material properties have been shown for these systems; these new properties often arise from certain crystal symmetries or lack thereof. One of interest is ferroelectricity in which a noncentrosymmetric crystal structure can lead to a switchable intrinsic electric dipole in our material. This can then lead to second-harmonic generation in which two photons enter a material at a given frequency and one photon exits the material at double the original frequency. The study presented here makes …


The Forest Of Claytor Nature Center As A Carbon Offset; Assessing The Sequestration Potential And Socioeconomic Implications, Sarah Mccollum May 2023

The Forest Of Claytor Nature Center As A Carbon Offset; Assessing The Sequestration Potential And Socioeconomic Implications, Sarah Mccollum

Undergraduate Theses and Capstone Projects

Cap and trade programs limit the amount of emissions an organization can produce. To neutralize unavoidable emissions, organizations can purchase carbon offsets from the carbon market. The ability to quantify greenhouse gas emissions offsets in forests increased the urgency and popularity of the carbon market because carbon dioxide (CO2) has a large role in climate change. The University of Lynchburg’s Claytor Nature Center’s 332-acre forest could be a viable revenue source because of its ability to remove CO2 from the atmosphere. In this research, the potential number of annual offsets from Claytor Forest was measured through a manual biomass survey. …


Understanding The Operations And Decision-Making Of Cow-Calf Farmers In Northwest Arkansas, Clayton Weyl May 2023

Understanding The Operations And Decision-Making Of Cow-Calf Farmers In Northwest Arkansas, Clayton Weyl

Agricultural Economics and Agribusiness Undergraduate Honors Theses

Societal pressure on farmers has become a more central part of the rhetoric surrounding livestock production. This study includes farmers in the discourse on the rhetoric surrounding climate change via interviews and simulations tailored to their operation. Previous research has addressed regenerative agricultural practices and conditions that influence farmer decision-making, but little research has analyzed decision-making in tandem with environmental practices. The literature reveals that cow-calf producer decision-making is influenced by their reliance on cattle as an income source, and farmers overall choose climate-friendly practices based on their perceptions about climate change. The goal of this research was to gather …


Fragment Based Drug Development Based On 6,7-Dimethoxyquinazoline As A Core Scaffold, Cody M. Orahoske May 2023

Fragment Based Drug Development Based On 6,7-Dimethoxyquinazoline As A Core Scaffold, Cody M. Orahoske

ETD Archive

The work entitled “Fragment Based Drug Design based on 6,7- Dimethoxyquinazoline core structure” presents a unique approach to drug discovery, specifically focusing on the pharmacophore 6,7-dimethoxyquinazoline. This study explores the structural diversity of 6,7-Dimethoxyquinazoline derivatives to identify other pharmacologically relevant targets, with evidence indicating that this core structure possesses intrinsic properties that make it suitable as a base structure of small molecule drugs. Furthermore, this pharmacophore has been observed in various approved therapeutics or drug candidates under investigation, highlighting its importance in drug discovery. My research showcases of 6,7-dimethoxyquinazoline core structure been derivatized to generate an anti-trypanosomiasis drug candidates and …


Characterizing Metabolic Activity Of Fish Liver Microsomes Towards Fluoxetine In Four Fish Species Using Michaelis-Menten Enzyme Kinetics, Morgan Steiner May 2023

Characterizing Metabolic Activity Of Fish Liver Microsomes Towards Fluoxetine In Four Fish Species Using Michaelis-Menten Enzyme Kinetics, Morgan Steiner

Honors College Theses

Discharge of pharmaceuticals into the environment is of emergent concern due to the unknown long-term effects on aquatic organisms. Wastewater treatment plants are not effective in completely removing pharmaceuticals, allowing them to be discharged into aquatic systems. To investigate the potential effects of fluoxetine, a common antidepressant, on aquatic species, the potential of four freshwater fish species to metabolize this drug was investigated. Livers from redbreast sunfish, bluegill, striped jumprock and bluehead chub were collected, homogenized, and centrifuged to collect the microsomes. These microsomes were used in an assay to determine the in vitro hepatic metabolism of fluoxetine by cytochrome …


Music Mentor, Jacob Webb May 2023

Music Mentor, Jacob Webb

Honors College Theses

Extra-curricular learning is on the rise, and many are interested in expanding their current knowledge by utilizing the recent increase in educational technology. While many forms of educational technology exist, there are few interactive and engaging platforms that teach music theory. Apps such as Perfect Ear and MyMusicTheory are great for becoming familiar with reading music and recognizing pitches, however, they often become dry with repetition and repeated tasks. By combining existing technologies that can complete real time conversions from raw audio to MIDI, our goal was to gather information such as harmonies, key and compatible chords from the user’s …


Biochar As A Lake Management Option For Harmful Algal Blooms: Lab Experiments And Bioassays, Brittany Mc Intyre May 2023

Biochar As A Lake Management Option For Harmful Algal Blooms: Lab Experiments And Bioassays, Brittany Mc Intyre

Graduate Theses and Dissertations

Harmful Algal Blooms (HABs) are an increasing global concern for water management due to their increased frequency, distribution, and toxin production. In freshwaters the growth of cyanobacteria (commonly known as blue-green algae), due to anthropogenic nutrient enrichment is the primary driver of HABS; these are often referred to as cyanoHABs. The management of cyanoHABs should be focused on in the watershed through best management and conservation practices or the physical, chemical and biomanipulation of the lake or reservoir that is experiencing these blooms. In this study, we examine the use of biochar as an option for the management or treatment …


Evaluation Of Hydrogeochemical Characteristics Of San Joaquin, Tulare, And Mojave Aquifers, Southern California, Maedeh Hassanvand May 2023

Evaluation Of Hydrogeochemical Characteristics Of San Joaquin, Tulare, And Mojave Aquifers, Southern California, Maedeh Hassanvand

Graduate Theses and Dissertations

Before making attempts to enhance and manage the quality of water, a thorough understanding of these processes is necessary since the chemical quality of groundwater is impacted by a number of linked processes. This would be more important in arid and semiarid regions like the southern part of California where more rely on groundwater for agriculture and drinking water uses than the other states. As a result, fundamental knowledge of the governing processes of groundwater chemistry is required for effective water resource management. Thus, this study is primarily concerned with three aspects in Mojave, Tulare, and San Joaquin aquifers: The …


Mechanisms Of Formation Of Novel Guanine-Guanine Cross-Links As Major End Products During One-Electron Oxidation Of Guanine Derivatives, Evan Dunn May 2023

Mechanisms Of Formation Of Novel Guanine-Guanine Cross-Links As Major End Products During One-Electron Oxidation Of Guanine Derivatives, Evan Dunn

Undergraduate Honors Theses

Guanine (G), as the most oxidizable base in DNA, is the major focus of studies of oxidation damage to DNA. The present thesis reports the first detailed characterization of G dimerization products potentially resulting from recombination of neutral G• radicals. Previous research has discovered a novel type of products of G• dimerization, D1 and D2, formed from one-electron oxidation of G derivatives. However, the mechanism of this dimerization remains elusive. While there appears to be a tautomeric equilibrium between two forms of G•, G(N1-H)• or G(N2-H)•, it remains unclear which intermediate participates in the formation of …


Sexual Dimorphism Of Glomerular Capillary Morphology In Rats, Zackarias Coker May 2023

Sexual Dimorphism Of Glomerular Capillary Morphology In Rats, Zackarias Coker

Undergraduate Honors Theses

Chronic kidney disease (CKD) progresses faster in males than females; however, the underlying mechanisms remain poorly understood. Sex differences in glomerular capillary morphology has been hypothesized to contribute, in part, to the increased susceptibility to hypertension-induced renal injury and CKD progression in males, but this has not been investigated. The goal of the present study was to assess glomerular capillary morphology in male vs. female rats with intact kidneys and after uninephrectomy (UNX). We hypothesized that glomerular capillary radii (RCAP) and length (LCAP) would be greater in male rats.

Male (n=4) and female (n=4) with intact …


An Analysis Of Factors Affecting Municipal Biochar Implementation In Voluntary Carbon Markets, Jadon Basilevac May 2023

An Analysis Of Factors Affecting Municipal Biochar Implementation In Voluntary Carbon Markets, Jadon Basilevac

Department of Environmental Studies: Undergraduate Student Theses

This paper serves as a review article and incorporates elements of survey research in order to identify and address factors inhibiting biochar availability from municipal sequestration projects in voluntary carbon marketplaces. In determining which barriers exist, and devising strategies for solving them, this study can help to expand the role of biochar in mitigating emissions contributing to climate change, and encourage project developers to support municipal biochar projects that provide various co-benefits. To do so, this study addresses how the pyrolysis production process might be made more efficient, economically viable, and see improved public image, the various urban sectors to …


Analyzing The Effects Of Cold Frontal Passage On The Feeding Habits Of Micropterus Salmoides (Largemouth Bass), Ethan Lang May 2023

Analyzing The Effects Of Cold Frontal Passage On The Feeding Habits Of Micropterus Salmoides (Largemouth Bass), Ethan Lang

Department of Environmental Studies: Undergraduate Student Theses

For many decades, it has been theorized as to what happens to the feeding habits of largemouth bass (Micropterus Salmoides) when a significant short term weather change occurs. Here in the midwest and all throughout the United States cold front boundaries are a weather phenomenon that occur on a regular basis. They can occur on a very large or small scale and have a rapid effect on the weather locally. These cold front systems have been looked at as one of the main drivers to having an effect on the feeding habits of largemouth. However, up until this point, any …


Physiological Distancing Affects Climate Change Through Spatial Differences, Janette Williams May 2023

Physiological Distancing Affects Climate Change Through Spatial Differences, Janette Williams

Department of Environmental Studies: Undergraduate Student Theses

Psychological distancing is best described as the human ability to separate ourselves socially, temporally, and spatial and use it to manipulate our perspectives. It is the belief that in order to perceive or understand the information, you have to be within a spatial range(Harvard Business Review,2015). Psychological distancing has been linked to climate change perspectives based on spatial differences. People who are closely affected by climate change and experience more are going to have more ideas and be proactive. The reduced distance by spatial differences correlated with perceptions of climate change. People who are farther from the coast and experience …


Roots Of Passion In Environmental Unl Students, Shane Vrbicky May 2023

Roots Of Passion In Environmental Unl Students, Shane Vrbicky

Department of Environmental Studies: Undergraduate Student Theses

“Passion” is an elusive idea - a simple word invented by man - able to depict vastly different realities and meanings dependent entirely on the user. Highly influential in nature, the simple thought of a passion within human beings can evoke a wide spectrum of strong emotions from pure joy and satisfaction to utter desperation and dread. Sometimes people have never known a life without their passion, guided by a headstrong feeling towards a path they have always dreamed of. Sometimes people can never seem to find passion, not knowing where to look and yet constantly chasing after it. Sometimes …


Fast -- Asymptotically Optimal -- Methods For Determining The Optimal Number Of Features, Saied Tizpaz-Niari, Luc Longpré, Olga Kosheleva, Vladik Kreinovich May 2023

Fast -- Asymptotically Optimal -- Methods For Determining The Optimal Number Of Features, Saied Tizpaz-Niari, Luc Longpré, Olga Kosheleva, Vladik Kreinovich

Departmental Technical Reports (CS)

In machine learning -- and in data processing in general -- it is very important to select the proper number of features. If we select too few, we miss important information and do not get good results, but if we select too many, this will include many irrelevant ones that only bring noise and thus again worsen the results. The usual method of selecting the proper number of features is to add features one by one until the quality stops improving and starts deteriorating again. This method works, but it often takes too much time. In this paper, we propose …


Microwave Synthesis Of Carbon Dot Nanoparticles, Hayden Ferguson May 2023

Microwave Synthesis Of Carbon Dot Nanoparticles, Hayden Ferguson

Undergraduate Honors Theses

This study aimed to improve the known microwave method to produce carbon dot nanoparticles from ethylenediamine and citric acid. Carbon dots have recently gained much attention as they have diverse applications, such as bioimaging and drug delivery reagents as cancer theranostics. Research was focused on establishing the ideal time for the synthetic reaction to produce carbon dot nanoparticles with the microwave method. After several trials, the 16-minute trial provided the best results based on Fourier transform infrared spectroscopy, ultraviolet-visible spectroscopy, fluorescence spectroscopy, and ultraviolet exposure.


Listening For Common Ground In High School And Early Collegiate Mathematics, Gail Burrill, Henry Cohn, Yvonne Lai, Dev P. Sinha, Ji Y. Son, Katherine F. Stevenson May 2023

Listening For Common Ground In High School And Early Collegiate Mathematics, Gail Burrill, Henry Cohn, Yvonne Lai, Dev P. Sinha, Ji Y. Son, Katherine F. Stevenson

Department of Mathematics: Faculty Publications

Solutions to pressing and complex social challenges require that we reach for common ground. Only through cooperation among people with a broad range of backgrounds and expertise can progress be made on issues as challenging as improving student success in mathematics. In this spirit, the AMS Committee on Education held a forum in May 2022 entitled The Evolving Curriculum in High School and Early Undergraduate Mathematical Sciences Education.1 This article is a report on that forum by the authors listed above, who were among the organizers and presenters.


Context-Aware Gaze-Based Interface For Smart Wheelchair, Tien Pham May 2023

Context-Aware Gaze-Based Interface For Smart Wheelchair, Tien Pham

Computer Science and Engineering Theses - Archive

Human-Computer Interfaces (HCI) is an essential aspect of modern technology that has revolutionized the way we interact with machines. With the revolution of computers and smart devices and the advent of autonomous vehicles and other machines, there has been a significant advancement in this area that brings convenience to users to interact with technology intuitively and efficiently. However, the importance of HCI goes beyond the convenience of everyday technology. It has become crucial in the development of assistive technologies that empower people with disabilities to live more independently. Person with disabilities, who lack control of one or more parts of …


Enhancing Health Tweet Classification: An Evaluation Of Transformer-Based Models For Comprehensive Analysis, Foram Pankajbhai Patel May 2023

Enhancing Health Tweet Classification: An Evaluation Of Transformer-Based Models For Comprehensive Analysis, Foram Pankajbhai Patel

Computer Science and Engineering Theses - Archive

The task of health tweet classification entails identifying whether a given tweet is health-related or not. While existing research in this area has made significant progress in classifying tweets into specific sub-domains of health, such as mental health, COVID-19, or specific diseases, there is a need for a more comprehensive approach that considers a broader range of health-related topics. This thesis addresses this need by proposing a diverse and comprehensive dataset that includes various existing health-related datasets, data collected through a keyword-based approach, and manually annotated data. However, the use of health-related keywords in a figurative or non-health context poses …


Emauth: A Usable Continuous Authentication Scheme, Vighnesh Sivaraman May 2023

Emauth: A Usable Continuous Authentication Scheme, Vighnesh Sivaraman

Computer Science and Engineering Theses - Archive

ABSTRACT: In recent years, wearables have become an integral part of daily life for most users. Wearables provide a seamless supplement to their main counterparts such as smartphones, and tablets. With the increasing prevalence of smart devices in a ubiquitous manner, protecting data has become a crucial aspect of security in all areas of life, as individuals can be vulnerable to such threats regardless of their location. As a security measure, authentication measures have been adopted. Traditional/ Legacy Authentication mechanisms such as TouchID, FaceID, and Password/PIN are incorporated into the everyday life of users. There also exists another mode of …


Combining Chiral Chromatographic Stationary Phases And N-Derivatization Strategies For The Qualitative And Quantitative Analysis Of D-Amino Acids, D-Amino Acid Containing Peptides And D-Amino Acid Related Secondary Metabolites Using Liquid Chromatography, Sam Sung May 2023

Combining Chiral Chromatographic Stationary Phases And N-Derivatization Strategies For The Qualitative And Quantitative Analysis Of D-Amino Acids, D-Amino Acid Containing Peptides And D-Amino Acid Related Secondary Metabolites Using Liquid Chromatography, Sam Sung

Chemistry & Biochemistry Dissertations - Archive

Amino acids are essential building blocks in all life on Earth. It was first mistakenly believed that only L-amino acids were of biological relevance in higher organisms, and D-amino acids were laboratory artifacts or biologically irrelevant. It is well accepted today that various D-amino acids exist in different organisms, including humans, and some even play critical roles in biological pathways and processes. In addition, aberrant levels of certain D-amino acids have been reported in patients with varying diseases. It has been proposed that the aberrant variations in the levels of D-amino acids in biological fluids may serve as biomarkers for …


Analysis Of Isotopic Isomers By Gas Chromatography And Molecular Rotational Resonance Spectroscopy And Enantioselective Method Development By Liquid Chromatography, Saba Aslani May 2023

Analysis Of Isotopic Isomers By Gas Chromatography And Molecular Rotational Resonance Spectroscopy And Enantioselective Method Development By Liquid Chromatography, Saba Aslani

Chemistry & Biochemistry Dissertations - Archive

This dissertation focuses on developing improved methods and a better understanding of gas and liquid chromatographic separation of isotopic isomers and enantiomers. The second and third chapters of this thesis discuss analytical determination of isotopic isomers using gas chromatography. Deuterated compounds have found applications in many fields. They are used in drug discovery due to increased stability and bioavailability and reduced toxicity of the deuterated drug molecules. Also, deuterated compounds are used to investigate reaction mechanisms and rate determining steps. One of the methods of synthesizing deuterated compounds is starting from lower molecular weight deuterated building blocks. Therefore, analysis and …