Physical Sciences and Mathematics Commons^™

Development And Application Of Small-Molecule Probes Targeting Ghrelin O-Acyltransferase, Jacob Moose

Dissertations - ALL

Ghrelin is a 28-amino acid peptide hormone that has wide-ranging physiological effects, including on metabolism, adipogenesis, insulin regulation, and addiction. Ghrelin offers an intriguing option for treatment of pathophysiologies related to these effects, as it requires a unique post-translational octanoyl modification to bind and activate its cognate receptor, growth hormone secretagogue 1a (GHSR). The enzyme responsible for this modification, ghrelin O-acyltransferase (GOAT) therefore offers the ability to modulate ghrelin signaling through inhibition of the maturation pathway. Due to a lack of structural or mechanistic information about GOAT, pharmaceutical development of molecules capable of GOAT inhibition has been desired, but few …

Enhancing Security And Robustness Of Contextual Human-Centric Sensing, Jingyu Xin

Dissertations - ALL

The rapid advancements in deep learning and smart hardware have accelerated the development of various automatic human-centric sensing applications. However, the intrusive nature of these sensing applications and the heterogeneity of sensory data pose challenges in real-world deployment. While performance is crucial, ensuring the security and robustness of these applications is equally imperative for their reliable operation. To tackle the challenges associated with security and robustness in human-centric sensing, this dissertation outlines two specific objectives: (1) mitigating false data injection attacks (FDIA) on sensing applications, and (2) establishing a generalized personalization framework for human sensing models. FDIA operates by injecting …

Fea Simulations For Thermal Distributions Of Large Scale 3dic Packages, Suxia Chen, Qiang Wu, Wayne Xun, Jiachen Zhang, Jianping Xun

Computer Science Faculty Publications and Presentations

As the market increases for Artificial Intelligence and High-Performance Computing applications, the geometry of 3-Dimensional Integrated Circuit packages becomes more complicated; therefore, predicting the thermal distributions of the structures becomes not only more important but also more challenging. The physics governing the thermal distribution is a 3-dimensional partial differential equation. In order to predict the thermal distributions, various approaches such as the layer modeling method have been invented. While practical, these approaches solve a simplified version of the differential equation placing an inherent limitation on their capabilities which may be improved upon. In this research we solve the actual differential …

Numerical Invariants Of Cohen-Macaulay Local And Graded Rings, Richard Francis Bartels

Dissertations - ALL

We characterize different classes of Cohen-Macaulay local rings (R,m, k) with positive Krull di?mension in terms of MCM approximations of finitely-generated R-modules. Assume R has a canonical module. For each finitely-generated R-module M, Auslander’s δ?invariant δR(M) equals the rank of a maximal free direct summand of the minimal MCM approxi?mation XM of M. We have δR(R/m) = 1 if and only if R is a regular local ring. Auslander defined the index of R, denoted index(R), as the infimum of positive integers n such that δR(R/mn ) = 1. When R is Gorenstein, we have index(R) ≤ gℓℓ(R) < ∞, where gℓℓ(R) denotes the generalized Loewy length of R, the smallest positive integer n such that mn ⊆ xR for some system of parameters x for R. We call such a system of parameters a witness to the generalized Loewy length of R. In Chapter 3, we generalize a theorem of Ding, who proved that if R is Gorenstein with infinite residue field k and Cohen-Macaulay associated graded ring grm(R), then gℓℓ(R) = index(R). We prove that if R is a one-dimensional Cohen-Macaulay local ring with finite index and nonzerodivi?sor x of order t with grm(R)-regular initial form x ∗ , then gℓℓ(R) ≤ index(R) +t −1. We use this estimate to derive a formula for the generalized Loewy length of a one-dimensional hypersurface R = kJx, yK/(f). If z is a witness to gℓℓ(R) such that z ∗ is grm(R)-regular, then gℓℓ(R) = ordR(z)+e(R)−1, where e(R) denotes the Hilbert-Samuel multiplicity of R. We compute the generalized Loewy lengths of several families {Rn} ∞ n=1 of one-dimensional hypersurfaces over finite and infinite fields such that gℓℓ(Rn) = index(Rn) for all n ≥ 1 or gℓℓ(Rn) = index(Rn) + 1 for all n ≥ 1. Lastly, we study a graded version of the generalized Loewy length of a Noetherian local ring for Noetherian k-algebras (R,m, k), where k is an arbitrary field and m is the irrelevant ideal of R. This invariant is called the generalized graded length of R and denoted ggl(R). After determining bounds for ggl(R) in terms of gℓℓ(R) and the degrees of generators for R, we compute the generalized graded length of numerical semigroup rings. We also characterize witnesses to the generalized graded length of numerical semigroup rings for semigroups with two generators. In Chapter 4, we study criteria for when an MCM module over a Gorenstein complete local ring R is stably isomorphic to an MCM approximation of a finitely-generated R-module of some fixed positive codimension r. If this condition holds for an MCM R-module M, we say with Kato that M satisfies the SCr-condition. If this condition holds for every MCM R-module, we say that R satisfies the SCr-condition. Only the SC1- and SC2- conditions have been characterized for Gorenstein complete local rings R. Kato proved that R satisfies the SC1-condition if and only if R is a domain, and R satisfies the SC2-condition if and only if R is a UFD. For rings of dimension d ≥ 3 and 3 ≤ r ≤ d, we prove an inductive criterion for when an MCM R-module satisfies the SCr-condition when its first syzygy module Ω1 R (M) satisfies the SCr−1-condition. We use this criterion to prove the equivalence of the SCd- and SCd−1-conditions for Gorenstein complete local rings of dimension d ≥ 3 that remain UFDs when factoring out certain regular sequences of length d −2.

Investigating Holography Using Classical And Quantum Simulations, Goksu Can Toga

Dissertations - ALL

In this thesis, we aim to develop classical and quantum simulations to test holography. Holography can be thought of in its most basic form as a duality that relates a d + 1 dimensional theory to a d dimensional one and the most famous holographic correspondence is the AdS/CFT duality where d + 1 dimensional weakly coupled gravity theory is related to a d dimensional CFT. We start by developing lattice simulations for the N = 4 super Yang-Mills model and explore an improved supersymmetric lattice action showing that it is free of the lattice artifacts that plagued earlier lattice …

Directional Dopant Migration By ‘Atomic Trapping’ In Core/Multi-Shell Quantum Dots, Chun Chu

Dissertations - ALL

The study of transition metal ion-doped semiconductor nanocrystals (NCs) has attracted increasing attention due to their unique optical, electronic, and magnetic properties which sparked considerable interest towards a wide range of applications in material science, renewable energy and biological systems. Besides the size- and shape-dependent behavior, doped nanomaterials exhibit new and/or enhanced optical properties, which are sensitive to the dopant location or dopant distribution throughout the solid crystal lattice. Our work primarily focuses on understanding and elucidating the mechanism of dopant ion migration inside the NCs during post-synthetic treatments, such as shell passivation and high-temperature annealing. Mn(II) dopants migration behavior …

Overcoming Controls And Noise Challenges For High Power Interferometric Gravitational-Wave Detectors, Elenna Capote

Dissertations - ALL

In August 2017, the Advanced LIGO and Advanced Virgo detectors made the first coincident detection of gravitational waves from a binary neutron star merger, GW170817. This multi-messenger detection, measured with both gravitational wave detectors and electromagnetic telescopes, emphasized the ability of ground-based gravitational-wave detectors to make exciting astrophysical discoveries that revolutionize understanding of the universe. In this new era of gravitational-wave astronomy, high detector sensitivity and reliable operation are required to enable more of these exciting detections. Ground-based gravitational-wave observatories are generally limited in sensitivity at low frequency by technical noise, at mid frequency by coating thermal noise, and at …

Defects And Deformation In Passive And Active Structural Glasses, Julia Ann Giannini

Dissertations - ALL

Glasses and disordered granular media represent a class of materials that are quite familiar to us, from the glass in windows and phone screens, to piles of fruits, grains, and sand. Further, living and active systems such as cellular tissues, collections of robots, and even human crowds behave as disordered solids when they are gathered at high enough densities. Despite their ubiquity, there are still many behaviors of these amorphous systems that lack a full understanding. Contrasting crystalline solids, the thermodynamic, vibrational, energetic, and mechanical properties of glasses are not well-characterized by solid state theory. In the case of active …

On Multi-Sensor Adaptive Birth Theory For Labeled Random Finite Sets Tracking, Anthony Trezza

Dissertations - ALL

This dissertation provides a scalable, multi-sensor measurement adaptive track initiation technique for labeled random finite set filters. The lack of a well-defined, systematic approach is problematic for many applications, especially when fusing ambiguous sensor measurements. We begin by showing that a naive solution leads to an exponential number of newborn components in the number of sensors. An efficient solution is derived by formulating a ranked assignment truncation problem. A truncation criterion is established for a labeled multi-Bernoulli random finite set birth density that has a bounded L1 error in the generalized labeled multi-Bernoulli posterior density. This criterion is used to …

Agroecology And Soil Stewardship: Values And Techniques Of Smallholder Farmers In Bernalillo County, Stephanie Olivas

Geography ETDs

Agrarian movements around the world use agroecology to build sovereignty and steward dynamic ecosystems. Research has shown that agroecological farmers steward more resilient crops, more resilient soil biomes, and greater biodiversity than conventional agriculture. GIS and remote sensing offer many tools to detect the impacts of these farmers on the environment, but it is less clear how such technologies fit into agroecological goals. This study asks: what values, experiences and knowledge do smallholder producers in Bernalillo County embody in their soil stewardship practices? Also, what experience or knowledge do smallholder producers in Bernalillo County have about remote sensing, and would …

The Soundscape Of The Grove: The Acoustic Environment Of A Visual Landmark, Bryce Barrett

Honors Theses

The objective of this project was to evaluate the soundscape throughout the Grove and the Circle (two popular outdoor spaces on the University of Mississippi campus) by determining the sound levels and people’s perceptions of sounds. The term soundscape is defined by a person’s perception of an acoustic environment in context. The human perceptions of sounds were gathered during soundwalks, which are walking tours of a given environment where participants provide opinions on their acoustic surroundings. Five soundwalk sessions were conducted with a total of 10 participants with varying environmental conditions. Statistically significant variations in perceptions and sound levels …

Fire Reconstructions In The Far North: Late Holocene Ecological Responses To Fire In Northern Alaska, Lee Frank-Depue

Theses - ALL

Palaeoecological reconstruction can characterize regional fire-regimes and reveal how drivers such as anthropogenic warming and vegetation change influence the fire system. This thesis adds to our knowledge of millennial-scale tundra fire-regimes by creating four new charcoal-based paleoecological records from lake sediment cores on the Alaskan North Slope. Statistical analyses of charcoal accumulation rate (CHAR # particles cm-2 yr-1) at three different size fractions were used to identify centennial-scale variability in biomass burned through time and identify individual fire events. These analyses were coupled with morphological identification and classification of charcoal particles to link charcoal production to hypothesized fuel source. The …

Burning Calories, Burning Ocean: Metabolic Rate In Bivalves As A Predictor Of Extinction Selectivity Through Time And During Rapid Global Warming, Siddharth Gavirneni

Theses - ALL

Organismal metabolic rate is linked to environmental temperature and oxygen consumption, and as such, may be a useful predictor of extinction risk during major climate- driven crises. However, metabolic attributes can be quantified in many ways, highlighting differing aspects of organisms’ ecology. Here, we estimate resting whole-body and mass-specific metabolic rates in post-Carboniferous bivalve taxa using body size and seawater paleotemperature to assess how metabolic rate determines survival both during and outside of intervals of rapid climate warming, or ‘hyperthermals’. Accounting for the effects of geographic range size, we find a pattern of preferential extinction of bivalves with lower total …

Investigating The Formation Of The Zirconium-Rich Lithologies Of The Grenville Province Using Zircon Thermometry Of Granitoids From The Adirondack Mountains, John St. Denny

Theses - ALL

The Grenville Province (1200-980 Ma) is known to consist of many rocks which are abundant in zircon. This is seen by the large size of Grenville-age zircons and their abundance in the detrital record. A possible explanation for this is the temperature at which these rocks formed. This hypothesis states that the melts which formed the zircon-rich Grenville lithologies were exceptionally high temperature, enabling them to incorporate a significant amount of zirconium. As it is believed that most zirconium in a melt is incorporated into zircon, a high concentration of zirconium in a magma would crystallize an abundance of zircon. …

Spectral Characterization Of High-Speed Sers Fluctuations, Makayla Schmidt, Emily A. Farley, Marit A. Engevik, Alexandre G. Brolo, Nathan Lemke, Nathan Lindquist

Science Symposium

The concept of plasmonic “hotspots” is central to the broad field of nanophotonics. In surface-enhanced Raman scattering (SERS), hotspots can increase Raman scattering efficiency by orders of magnitude. Hotspot dimensions may range from a few nanometers down to the atomic scale and are able to generate SERS signals from single molecules. However, these single-molecule SERS signals often show significant fluctuations, and the concept of intense, localized, yet static hotspots has come into question. Recent experiments have shown these SERS intensity fluctuations (SIFs) to occur over an extremely wide range of timescales, from seconds to micro-seconds, due to the various physical …

Ankle Mobility And Balance In A Healthy College-Aged Population: A Correlational Study, Anna Johnson, Maddy Roiger, Ellie Stewart, Leah Jackson

Science Symposium

This study aimed to investigate the relationship between ankle mobility and balance in a young, healthy population, filling a gap in existing literature primarily focused on older adults. The findings revealed no significant correlation between ankle mobility and balance measures in the college-aged subjects. While previous research in elderly populations suggested a link between ankle mobility and balance, this study suggests that such a relationship may not hold true for younger individuals. These results underscore the importance of considering age-related differences and overall health status when exploring factors affecting balance, potentially guiding future research and intervention strategies aimed at improving …

Search For Vector-Like B Quarks In Cms Run 2, Kalin Johnson, Xiaohe Shen, Julie Hogan

Science Symposium

We present a search for a single vector-like B quark that decays to a top quark and W boson. In the single lepton final state, the B quark can be reconstructed from the lepton, missing transverse momentum, and one large-radius jet. We will present developments of the RDataFrame workflows for the search and optimization of the B quark reconstruction process.

Effect Of Recommending Users And Opinions On The Network Connectivity And Idea Generation Process, Sriniwas Pandey, Hiroki Sayama

Northeast Journal of Complex Systems (NEJCS)

The growing reliance on online services underscores the crucial role of recommendation systems, especially on social media platforms seeking increased user engagement. This study investigates how recommendation systems influence the impact of personal behavioral traits on social network dynamics. It explores the interplay between homophily, users’ openness to novel ideas, and recommendation-driven exposure to new opinions. Additionally, the research examines the impact of recommendation systems on the diversity of newly generated ideas, shedding light on the challenges and opportunities in designing effective systems that balance the exploration of new ideas with the risk of reinforcing biases or filtering valuable, unconventional …

Exploring The Mandelbrot Set, James Shirley

Electronic Theses and Dissertations

The Mandelbrot set is a mathematical mystery. Finding its home somewhere be-
tween holomorphic dynamics and complex analysis, the Mandelbrot set showcases
its usefulness in fields across the many realms of math—ranging from physics to nu-
merical methods and even biology. While typically defined in terms of its bounded
sequences, this thesis intends to illuminate the Mandelbrot set as a type of param-
eterization of connectivity itself, specifically that of complex-valued rational maps
of the form z → z² + c. This fully illustrated guide to the Mandelbrot set merges
the worlds of intuition and theory with a series of …

Deformation Mapping And Modeling Of The Aleutian Volcanoes With Insar And Numerical Models, Jiahui Wang

Earth Sciences Theses and Dissertations

Surface deformation mapping is an essential component for comprehensive monitoring of volcanic activities, serving as a vital tool for discerning crucial insights into magma dynamics, storage, and migration for accurate hazard forecasting, assessment, and mitigation. However, monitoring of the volcanic deformation across the Aleutian volcanic arc is usually limited by the lack of terrestrial sensors deployed due to their remote locations and hostile environmental conditions, necessitating alternative methodologies for data acquisition and analysis.

My PhD study aims at precisely mapping the crustal deformation for the Aleutian volcanoes and tracking the evolution of the magmatic system with Interferometric Synthetic Aperture Radar …

The Geology And Geochemistry Of The Western Iron Ore Group Greenstone Belt, Singhbhum Craton, Eastern India, Jordan Wright

Earth Sciences Theses and Dissertations

This thesis presents new data on the origin of the Western Iron Ore Group (W-IOG), a Paleoarchean succession deposited on sialic rocks of the Singhbhum Craton. U-Pb ages from zircons from a tuff overlying the Lower Shales just below a banded iron formation (BIF) pin the age of the section to 3.39 Ga. Unconformably overlying the whole IOG section is the Darjing Group, which contains the Birtola Sandstone (on the basis of this work, now estimated to be 2.35 Ga). The lack of penetrative deformation and low-grade metamorphism makes these rocks excellent subjects for combined radiogenic and stable isotope studies. …

Robust Prediction Of Charpy Toughness Of Additively Manufactured Kovar Using Deep Convolutional Neural Networks, Nathan R. Bianco

Mathematics & Statistics ETDs

Understanding the reason for mechanical failures of manufactured parts in their operating environments is critical to prevention of future failures. However, in-situ post-mortem evaluation of physical properties, such as fracture toughness, is time consuming and alters the condition of the material, leading to potentially misleading findings. In this study, additively manufactured test coupons were produced over a wide range of process conditions to test the impact toughness of a material. The Charpy V-Notch toughness was measured on over 200 samples alongside corresponding optical images of both sides of the fracture surface. Convolutional neural network models were trained to correlate fracture …

Entanglement With Neutral Atoms In The Simulation Of Nonequilibrium Dynamics Of One-Dimensional Spin Models, Anupam Mitra

Physics & Astronomy ETDs

Quantum entanglement is a key ingredient for quantum information processing with capabilities beyond that of classical computation. We study the generation and role of entanglement in the dynamics of spin-1/2 models, both for the design of quantum gates for general-purpose quantum computation and for quantum simulation of interacting spin models. We introduce the neutral atom Mølmer-Sørensen gate, involving rapid adiabatic Rydberg dressing interleaved in a spin-echo sequence. We show its robustness to quasi-static experimental imperfections and favorable scaling with the time-energy scales of Rydberg-mediated entanglement generation. In quantum simulation, we consider critical behavior in quench dynamics of transverse field Ising …

Depositional Facies Analysis Of The Cotton Valley Group Sandstones Of The Blackburn Field, Northern Louisiana Using Well Logs And Cores; Implications For Carbon Sequestration, Frederick Owusu

Electronic Theses and Dissertations

The Cotton Valley Group (CVG) consists of tight sandstones with heterogeneous reservoir properties due to variations in depositional environments and diagenesis, spanning across eastern Texas through the Florida panhandle. It has served as a hydrocarbon target since the 1940s, and with recent technological advances, there is renewed exploration of the tight reservoirs within the group. Across northern Louisiana, the CVG has moderate to good reservoir properties, whereas those south extending westward across the Sabine uplift into east Texas decrease in porosity and permeability. With reservoir depletion coupled with its relatively simple mineralogy, these sandstone units may serve as good, localized …

Investigation Of Residual Mineral Content Of Bauxite Stockpiles, Saline Mining District, Arkansas, U.S.A., Melanie L. Ertons

Electronic Theses and Dissertations

The former mining town of Bauxite is in the Saline County Mining District, in central Arkansas. Bauxite is located approximately 40 km (25 mi) southwest of Little Rock just east of Benton, Arkansas. This area contains extensive deposits of bauxite ore and nepheline syenite previously mined by Aluminum Company of America using open pit and subsurface mining techniques. This study incorporates five bauxite stockpiles (SP1, Clay, SP2, SP3, SP4) with varying amounts of alumina content situated on approximately 10 acres of land within an area of the former mine recognized as Section 20. Over the past several years, there has …

Comparison Of Various Theoretical Measures Of Aromaticity Within Monosubstituted Benzene, Caleb K. Swain, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

The effects of monosubstitution on the aromaticity of benzene are assessed using a number of different quantitative schemes. The ability of the mobile π-electrons to respond to an external magnetic field is evaluated using several variants of the NICS scheme which calculate the shielding of points along the axis perpendicular to the molecule. Another class of measures is related to the drive toward the uniformity of C-C bond lengths and strengths. Several energetic quantities are devised to approximate an aromatic stabilization energy and the tendency of the molecule to maintain planarity. There is a lack of consistency in that the …

Statistical Approaches For The Early Detection Of Colorectal Cancer Using Longitudinal Biomarkers, Emily Berry

Statistical Science Theses and Dissertations

Colorectal cancer (CRC) is the third leading cause of cancer-related death in the United States [45]. CRC is believed to advance from adenomatous polyps creating a unique opportunity for both early detection and cancer prevention [4, 23]. Like other diseases, CRC screening reduces mortality by detecting cancer at earlier, more treatable stages; however, it can also reduce incidence through the removal of precancerous lesions [4]. As a result, screening is recommended for average-risk adults ≥ 45 years of age and includes a variety of tests [4, 12]. Despite alternate screening options, colonoscopy capacity is often cited as a barrier to …

An Examination Of Behavior Of Youtube Commenters, John E. Leonard

Computer Science ETDs

YouTube comments are a unique form of social media, as viewers mainly interact with other viewers through comments sections, and cannot choose to interact with specific people. This lack of control over which comments are presented to them forces users to view spam.

Multiple general patterns of behavior were found in the dataset of YouTube comments. For example, most users posted just after a video’s publication. In addition, users tended to watch videos in the evening over the early morning.

A novel method was found for quantifying the likelihood of coordinated accounts being controlled by one person using time sharing. …

Online Temporal Data Mining And Learning: Pursuing Enhanced Efficiency And Robust Algorithms, Sheng Zhong

Computer Science ETDs

Time series data mining and learning serve as a cornerstone across various domains, including finance, healthcare, and science. Recent advancements in network and sensor technologies have ignited an increasing interest in real-time temporal data mining and learning techniques. Various tasks benefit from these techniques, such as environmental monitoring, event detection, anomaly identification, and forecasting. However, these techniques still face significant challenges in the online environment settings, encompassing aspects like efficiency, accuracy, robustness, and scarcity of labeled data. This dissertation presents four innovative solutions: FilCorr, DCT-MASS, FewSig, and BitLINK to overcome these challenges. We evaluate each method and showcase their practical …

Unboxing The Complicated Near Term Climatic And Geomorphic History Of Mars, Joshua Matthew Williams

Earth and Planetary Sciences ETDs

It has long been thought that glacial processes were unlikely within the tropical regions of Mars. However, growing evidence, including this work has identified and quantified relic glacial forms within the equatorial regions. These findings have major implications for understanding Martian climate history and its sensitivity to changes in insolation. As well, the presence of ice in the equatorial region of Mars has significant implications for the past global redistribution of the water ice in the Martian cryosphere. In this manuscript, I clarify and refine our understanding of the morphology of glacial features in the equatorial zone by applying novel …