Physical Sciences and Mathematics Commons^™

Recommendations For Sustainable Tourism In Patagonia: An Exploratory Analysis Of Sustainable Tourism In Costa Rica, The Nordic Region, And Thailand’S Communities, Julia K. Lowery

Undergraduate Honors Theses

This thesis explores different levels of governance and its role towards actualizing sustainable tourism in Patagonia. With the growing threat of climate change, international destinations such as Patagonia are looking to continue building their tourism industries in a sustainable way. Through analyzing case studies of national governance in Costa Rica, multi-national governance in the Nordic region, and community-based tourism in Thailand, we can better understand how each form of governance has the potential to create a sustainable tourism industry. With this understanding of successful governance in my case studies, as well as understanding the historical and political forces that have …

Voting Rules And Properties, Zhuorong Mao

Undergraduate Honors Theses

This thesis composes of two chapters. Chapter one considers the higher order of Borda Rules (Bp) and the Perron Rule (P) as extensions of the classic Borda Rule. We study the properties of those vector-valued voting rules and compare them with Simple Majority Voting (SMV). Using simulation, we found that SMV can yield different results from B1, B2, and P even when it is transitive. We also give a new condition that forces SMV to be transitive, and then quantify the frequency of transitivity when it fails.

In chapter two, we study the `protocol paradox' of approval voting. In approval …

The Regulation Of Atg9a-Mediated Aggrephagy By An Ulk1-Independent Atg13-Atg101 Complex, Joshua Youngs

Undergraduate Honors Theses

Aggrephagy, a type of autophagy, is an essential cellular process by which protein aggregates are collected and broken down in the lysosome. Protein aggregates are implicated in several diseases including Alzheimer’s disease, diabetes, and cancer. Here, we investigate the ATG13-ATG101 protein complex, a sub-complex of the canonical ULK1 complex whose regulatory role in aggrephagy is not completely understood. We also develop a protein fragment complementation (PFC) assay using the biotin ligase TurboID to study the functions of the ATG13-ATG101 complex with increased specificity. We demonstrate that ATG13 is required for optimal degradation of p62-ubiquitin condensates. We also show that a …

Finding Patterns In The Inertia Of The Distance Squared Matrix Of Unicyclic Graphs, Kellon Sandall, Mark Kempton, Christian Howell

Undergraduate Honors Theses

We analyze the spectrum of the distance squared matrix of a tree and give a relation between the inertia of the distance squared matrix and the structure of the tree. We take the result one step further and consider the addition of exactly one cycle in the tree. We obtain an expression for the inertia of the distance squared matrix of a cycle graph. We obtain a bound on the inertia of the distance squared matrix of an arbitrary unicyclic graph.

Microplastics In Our Oceans May Inhibit Aerosols From Cooling The Atmosphere, Michael Rafla

Undergraduate Honors Theses

Sea spray aerosol (SSA) are liquid gaseous particles emitted directly from the ocean, making their way into the atmosphere. It is hypothesized that SSA enters the atmosphere from mechanical processes such as wind and ocean waves. Winds and waves promote bubble formation and these bubbles which make their way onto the ocean surface. After these wave-created bubbles rise to the ocean surface, the bubble ruptures and water evaporates which causes gaseous drops to be released into the air: this is the main source of SSA. SSA matter is known to affect Earth’s climate, by scattering light energy and solar radiation …

Characterization Of Bimetallic Silver-Copper Nanoinks With Hydroxyethyl-Cellulose Additives, Daniel Brunick

Undergraduate Honors Theses

Coinage metal nanoparticles remain an intriguing subject for research due to their industrial versatility. Primary applications of coinage metal nanoparticles include printed electronics, solar panels, and sensors. Inks formulated with the nanoparticles are conductive and thus useful for fabricating sensors. Silver-copper nanoalloy inks are viable for the fabrication of flexible sensing devices for the detection of volatile organic compounds. One of the challenges is the ability to synthesize composition-controllable alloy nanoparticles at room temperature through wet chemical methods and achieve controllable sintering at room temperature. This work addresses the challenges by investigating the room-temperature synthesis of silver-copper alloy nanoparticles and …

Synthesis And Characterization Of Hydrazine Derivatives Of Coumarin For Bioorthogonal Chemistry Inside Cells, Akiva J. Grimaldi

Undergraduate Honors Theses

Protein carbonylation is one manifestation of oxidative stress, which is characteristic of many diseases. Our lab has developed several coumarin-hydrazine based fluorescent probes capable of detecting carbonylation in live cells via the formation of hydrazone conjugates. As an effort to expand and improve on these achievements, this work presents new data regarding the synthesis and characterization of three such probes. Two of the probes—julolidine coumarin hydrazide (JCH) and trifluoromethyl coumarin hydrazine (TFCH)—were previously synthesized by our lab. Here, JCH is studied in terms of its reaction speed and fluorescence enhancement in acylhydrazone formation with aldehydes under various conditions and catalytic …

Optimization Of Paper-Based Substrates For Surface Enhanced Raman Spectroscopic Biosensor Development, Kaylee M. Cappuccio

Undergraduate Honors Theses

Advancements in the field of analytical chemistry have greatly expanded the development of biosensors for the detection of a wide array of diseases. This study aims to optimize an affordable paper-based nanocomposite biosensor that utilizes surface-enhanced Raman spectroscopy (SERS). Specifically, it investigates the preparation parameters for a paper-based SERS substrate, including nanoparticle administration and drying procedures. A particular focus of this work is to assess how the wax-defined paper channels can effectively enhance SERS intensity. The results revealed that while the wax-printed wells can define the nanoparticle administration for SERS detection, wax backing may reduce the sensitivity of SERS by …

Computational Analysis Of A Mn-Based Electrocatalyst With Primary Amine Substituents In The Secondary Coordination Sphere For Co2 Reduction, Erin Urban

Undergraduate Honors Theses

The purpose of this research was to report the mechanism for the two-electron, two-proton conversion of CO 2 to CO and H 2 O using a manganese(I) electrocatalyst, Mn(L)(CO) 3 Br (where L = bipyridyl ligand with aryl-amine moieties installed at the 6 position of 2,2’-bipyridine), synthesized by the Jurss group, including any other competing reactions, such as the hydrogen evolution reaction (HER). The “protonation- first” and “reduction-first” pathways were considered for CO 2 RR. Density functional theory (DFT) calculations were performed to determine the redox potentials and Gibb’s free energies for each step in the mechanism for CO 2 …

Synthesis And Characterization Of Ternary Pt Nanoally Catalysts For Fuel Cells, Ylith Peck

Undergraduate Honors Theses

A hydrogen fuel cell is an electrochemical device that converts oxygen and hydrogen into electrical energy while producing water as the only by-product, which has attracted growing interest, especially in the automotive industry. This technology is efficient and has zero pollution to the environment, in contrast to the direct use of fossil fuels in combustion engines which produce pollution and greenhouse gas emissions. One of the key components for hydrogen fuel cells is the catalyst that operates at the cathode, which currently use platinum. Due to the scarce amount of platinum in the world, the manufacturing cost for fuel cells …

Friedel-Crafts Alkylation Of Benzene With A Superacid Catalyst, Josh T. Cutright

Undergraduate Honors Theses

Long-chain alkylbenzenes are industrially synthesized precursors to commercial surfactants such as laundry detergent. The currently used catalysts in the processes of their synthesis are corrosive and harmful to the environment. These problems can be avoided utilizing heterogeneous highly acidic catalysts. Solid catalysts do not corrode equipment and are relatively simple to remove from the post-reaction mixture. Phosphotungstic acid (PTA) supported on silica gel could be a possible catalyst due to its high acidity with an estimated pKa ≈ -13. The catalyst PTA-SiO₂ was prepared via the sol-gel method to covalently embed it in a silica support. The catalyst was …

Nitrogen Doping Of Electrochemically Activate Carbon Screen-Printed Electrodes, Ethan Galloway

Undergraduate Honors Theses

Screen printed electrodes (SPEs), which are prepared by patterning conductive inks or pastes onto an insulating support (e.g., plastic film), are widely employed as sensing and biosensing platforms due to their ease of fabrication and relatively low cost. This is especially applicable to electrodes of this nature prepared with carbon-based inks (SPCEs). To date, the most successful and significant commercial application of SPEs has been as test strips for glucose meters. Despite the maturity of this technology, SPE research remains very active as improvements in sensitivity and selectivity, which often involve modifying the electrode surface, hold the key to advancing …

Development Of A Prototype Electron Detector For Use In Ucna+, Richard Mcdonald

Undergraduate Honors Theses

The UCNA Experiment at the Los Alamos Neutron Science Center (LANSCE) uses an electron spectrometer to observe angular correlations between the neutron spin and the momenta of β particles emitted during the process of β decay. These angular correlations give rise to an asymmetry determined by the ratio of two coupling constants, gA and gV . Combined with neutron lifetime measurements, these observations probe physics beyond the standard model through unitarity tests of the Cabbibo-Kobayashi-Maskawa Matrix. UCNA’s current spectrometer uses a multi-wire proportional chamber and a plastic scintillator coupled to four photomultiplier tubes (PMTs) by 2 meters of light guides …

Simulating Polistes Dominulus Nest-Building Heuristics With Deterministic And Markovian Properties, Benjamin Pottinger

Undergraduate Honors Theses

European Paper Wasps (Polistes dominula) are social insects that build round, symmetrical nests. Current models indicate that these wasps develop colonies by following simple heuristics based on nest stimuli. Computer simulations can model wasp behavior to imitate natural nest building. This research investigated various building heuristics through a novel Markov-based simulation. The simulation used a hexagonal grid to build cells based on the building rule supplied to the agent. Nest data was compared with natural data and through visual inspection. Larger nests were found to be less compact for the rules simulated.

Stumbling Into Virtual Worlds. How Resolution Affects Users’ Immersion In Virtual Reality And Implications For Virtual Reality In Therapeutic Applications, Brianna Martinson

Undergraduate Honors Theses

Studies of how users experience Virtual Reality (VR) have thus far failed to address the extent to which rendering resolution and rendering frame rate affect users’ sense of immersion in VR, including applications of VR involving simulators, treatments for psychological and mental disorders, explorations of new and nonexistent structures, and ways to better understand the human body in medical applications.

This study investigated if rendering resolution affected users’ sense of immersion in VR. This was conducted by comparing the responses of two groups, relative to two measures of participant immersion: (a) participant’s sense of presence and (b) participant’s sense of …

Extraction And Partial Purification Of An Antibiotic-Like Compound From The Soil Bacterium Rhodococcus Strain Kchxc3, Elizabeth Bond

Undergraduate Honors Theses

Rhodococcus bacteria have many secondary metabolic pathways that may produce novel natural products. The bacterium Rhodococcus strain KCHXC3 was isolated from a soil sample collected near Kingsport, Tennessee and was found to produce an inhibitory compound active against a broad array of bacterial species, including the Gram negative pathogen Shigella sonnei. The aim of this research is to extract and purify the compound for future structure elucidation. A mixture of compounds from 3 month old agar plates inoculated with strain KCHXC3 was extracted using ethyl acetate. The crude extract was then partially purified utilizing a Sephadex LH-20 column, followed …

Alkali Linewidths Under High Temperatures And Pressures Of 3he, Michael Parker

Undergraduate Honors Theses

Current research at Thomas Jefferson National Accelerator Facility is being conducted to study the spin structure of the neutron through collisions with polarized 3He nuclei. The helium is contained in high pressure glass vessels (called cells) along with nitrogen, rubidium, and potassium. To deduce the spin structure from collisions, we need to know the precise number density of 3He in the cell. The process of polarizing 3He through spin-exchange optical pumping requires nitrogen and alkali metal. We can use the absorption linewidths of rubidium and potassium to more accurately determine the density of helium. Throughout my research, I collected absorption …

Bayesian Spatial Model Development Of Soil Core Organic Matter As A Proxy For Blue Carbon Stocks Within The Chesapeake Bay, Christian Longo

Undergraduate Honors Theses

Blue carbon is carbon captured and stored within bodies of water and their ecosystems. Blue carbon stocks are very important due to their ability to store carbon away from the atmosphere. The destruction of these stocks can accelerate climate change. In particular, we wish to assess blue carbon stock within the Chesapeake Bay. Previous studies have only used geographical features to predict blue carbon stock levels. The big picture question this thesis was meant to answer is: What is the best approach for building a statistical model that factors in both spatial parameters and geographical features to predict blue carbon …

An Atomic Magnetometer Based On Nonlinear Magneto-Optical Polarization Rotation, Jiahui Li

Undergraduate Honors Theses

Magnetometers with high precision and accuracy have wide applications across various areas. We are developing an atomic magnetometer based on nonlinear magneto-optical rotation (NMOR). The magnetometer measures the polarization rotation of a light field, which is proportional to the magnetic field strength. However, such a magnetometer usually has a limited operation range and stops working for fields stronger than the Earth's magnetic field. To overcome this shortage, we implement frequency and amplitude modulation that induces side frequencies in the Fourier space which allows us to measure strong magnetic fields, up to 200 mG. We have achieved 60 pT sensitivity for …

Development Of A Vector Magnetometer Based On Electromagnetically Induced Transparency In 87rb Atomic Vapor, Alexander Toyryla

Undergraduate Honors Theses

We present progress towards the development of an atomic magnetometer capable of accurate scalar and vector magnetic field measurements with high sensitivity and no need for external calibration. The proposed device will use the interaction between a bi-chromatic laser field and rubidium vapor to derive magnetic field magnitude and direction from measured amplitudes of Electromagnetically Induced Transparency (EIT) resonances. Since the proposed method requires precision control of light polarization, we observe the performance capabilities of a liquid crystal device to dynamically rotate the polarization of the laser field. Another goal in this project is to establish a polarization locking mechanism …

Development Of Classroom Tools For A Risc-V Embedded System, Lucas Phillips

Undergraduate Honors Theses

RISC-V is an open-source instruction set that has been gaining popularity in recent years, and, with support from large chip manufacturers like Intel and the benefits of its open-source nature, RISC-V devices are likely to continue gaining momentum. Many courses in a computer science program involve development on an embedded device. Usually, this device is of the ARM architecture, like a Raspberry Pi. With the increasing use of RISC-V, it may be beneficial to use a RISC-V embedded device in one of these classroom environments. This research intends to assist development on the SiFive HiFive1 RevB, which is a RISC-V …

Pliocene Wood From The Gray Fossil Site, Owen Madsen

Undergraduate Honors Theses

The Gray Fossil Site in northeastern Tennessee preserves materials from a 5-million-year-old ecosystem, including wood from nearby trees. This study consists of three parts: conservation of wood remains, identification of taxonomic groups represented by the fossil wood, and measuring the organic content of fossil wood from the Gray Fossil Site. When excavated, wood specimens from the site are saturated due to a high local water table. After testing seven different techniques to dry wood specimens, wrapping a specimen in string and allowing it to dry slowly was the method least likely to cause warping and cracking. Microscopic examination of wood …

Intraday Algorithmic Trading Using Momentum And Long Short-Term Memory Network Strategies, Andrew R. Whitinger Ii

Undergraduate Honors Theses

Intraday stock trading is an infamously difficult and risky strategy. Momentum and reversal strategies and long short-term memory (LSTM) neural networks have been shown to be effective for selecting stocks to buy and sell over time periods of multiple days. To explore whether these strategies can be effective for intraday trading, their implementations were simulated using intraday price data for stocks in the S&P 500 index, collected at 1-second intervals between February 11, 2021 and March 9, 2021 inclusive. The study tested 160 variations of momentum and reversal strategies for profitability in long, short, and market-neutral portfolios, totaling 480 portfolios. …

Detecting The Intensity Of Denial-Of-Service Cyber Attacks Using Supervised Machine Learning, Abigail Hubbard

Undergraduate Honors Theses

Denial-of-Service (DoS) attacks are aimed at shutting a machine or network down to block users from accessing it. These attacks can be difficult to detect and can cost millions in damages or lost earnings. Since the first DoS attack occurred in 1999, the way DoS attacks have been launched has become more complicated, making them more elusive and harder to detect. The first step to detect and mitigate a DoS attack is for a system to identify the malicious traffic.

In this experiment, we aim to identify the malicious traffic within ten seconds. To do this the project was divided …

Gas-Phase Proton Affinities For Twenty Of The Proline-Containing Dipeptides, Henry Cardwell

Undergraduate Honors Theses

Peptide fragmentation plays a crucial role in the analysis of proteins through mass spectrometry-based proteomics. Most proteomics experiments take place in the low-energy regime and are governed by the mobile proton model which predicts random cleavages along the peptide backbone; however, there sometimes arise circumstances where the mobile proton model fails causing sequencing algorithms to misidentify peptides. One such example is noted in the “proline effect” wherein proline-containing peptides preferentially fragment N-terminal. While it has been established that the “proline effect” is due to the rigidity and basicity of the proline N-terminus, a further understanding of the factors influencing the …

Co-Planar Waveguides For Microwave Atom Chips, Morgan Logsdon

Undergraduate Honors Theses

This thesis describes research to develop co-planar waveguides (CPW) for coupling microwaves from mm-scale coaxial cables into 50 μm-scale microstrip transmission lines of a microwave atom chip. This new atom chip confines and manipulates atoms using spin-specific microwave AC Zeeman potentials and is particularly well suited for trapped atom interferometry. The coaxial-to-microstrip coupler scheme uses a focused CPW (FCPW) that shrinks the microwave field mode while maintaining a constant 50 Ω impedance for optimal power coupling. The FCPW development includes the simulation, design, fabrication, and testing of multiple CPW and microstrip prototypes using aluminum nitride substrates. Notably, the FCPW approach …

Climate Change And Conservation Of Milkweed: Evidence Of Extensive Admixture Between Common Milkweed And Poke Milkweed, Elizabeth Davies

Undergraduate Honors Theses

Global climate change can drive many changes in species interactions. One primary way it affects species is by changing climates, causing species to expand their ranges and allowing them to interact with species from whom they were previously isolated. In plants, new species interactions can result in hybridization – the creation of hybrid offspring between two separate species. This hybridization can increase gene flow between the species and lead to introgression, the transfer of genetic material from one species to another through hybrid backcrossing with the parent species. My thesis investigates hybridization in the model system Asclepias (milkweed) by analyzing …

Chemical Analysis Of Organic Compounds In Dew Water, Monica Dibley

Undergraduate Honors Theses

Water films on outdoor surfaces, such as dew, can act as a reservoir for organic molecules deposited from the atmosphere and they present a potential reactive medium for chemical transformations. To better understand the flux of volatile organic compounds from evaporating films, the composition and reactivity of the complex mixture of dissolved organic material (DOM) found in these films need to be characterized. Previous studies have measured the salts and the small organic molecules in dew collected on clean Teflon surfaces or condensers. Here, we expand on this by probing the organic chemicals found on natural outdoor surfaces covered in …

Investigation Of Tertiary Impact Cratering And Relation To Impact Physics Theory, Mikayla Huffman

Undergraduate Honors Theses

Extraterrestrial impact crater formation is important in many subfields of planetary science, including geochronology, planetary formation, and dynamic fragmentation theory. Current dynamic fragmentation theory lacks scale dependence and relies heavily on terrestrial data. Exploring a range of impact and ejecta velocities as is produced by cratering events on the Moon may bridge the gap between heavily terrestrial-based theory and planetary data. The secondary craters of secondary craters deemed “tertiary craters,” have been theorized, but planetary images have not been of sufficient resolution to effectively search for them until recently. Tertiary craters are formed by relatively low-velocity fragments ejected by nearby …

Modern Theory Of Copositive Matrices, Yuqiao Li

Undergraduate Honors Theses

Copositivity is a generalization of positive semidefiniteness. It has applications in theoretical economics, operations research, and statistics. An $n$-by-$n$ real, symmetric matrix $A$ is copositive (CoP) if $x^T Ax \ge 0$ for any nonnegative vector $x \ge 0.$ The set of all CoP matrices forms a convex cone. A CoP matrix is ordinary if it can be written as the sum of a positive semidefinite (PSD) matrix and a symmetric nonnegative (sN) matrix. When $n < 5,$ all CoP matrices are ordinary. However, recognizing whether a given CoP matrix is ordinary and determining an ordinary decomposition (PSD + sN) is still an unsolved problem. Here, we give an overview on modern theory of CoP matrices, talk about our progress on the ordinary recognition and decomposition problem, and emphasis the graph theory aspect of ordinary CoP matrices.