Physical Sciences and Mathematics Commons^™

Spring 2021

Scientia

From the Dean: A Decade of Purpose and Progress; Lab Notes: Alumna Wins Gordon Bell Special Prize, New Scholarships, Vaccination Site Volunteers; Women in Science Lecture, National Institutes of Health Grants, "Unequal Cities" Research; All Hands on Deck: Inspired pandemic approaches showcase interdisciplinary acumen in action; Unlocking Potential: Christopher Beasley thinks psychology is key to academic transformation for the formerly incarcerated; Puzzle Master: Bridget Tenner goes to pieces solving problems in cutting-edge mathematics

Farm To Boardroom: How Improving Farm Conditions Leads To Sustained And Ethical Profit, Emily Mueller

Student Theses 2015-Present

As a society evolving and innovating at a pace faster than ever before seen in human history, we find ourselves at a crossroads of dealing with planetary boundaries and improving social standards. We are met with a crisis just thirty years away; the crisis of needing to be able to effectively and sustainably feed ten billion people across the globe. The 20th century brought on a booming age for industrializing the food system in order to increase yield and thus profit. The new process was a significant breakthrough at its time, but now we must face the question of when …

Generalized Bms Algebra At Timelike Infinity, A. H. Anupam, Aniket Khairnar, Arpan Kundu

Faculty and Student Publications

BMS (Bondi-Metzner-Sachs) group (and its various generalizations) at null infinity has been studied extensively in the literature as the symmetry group of asymptotically flat spacetimes. The intricate relationship between soft theorems and the BMS symmetries has also motivated the definition of such asymptotic symmetries to timelike infinity [M. Campiglia, Null to time-like infinity Green's functions for asymptotic symmetries in Minkowski spacetime, J. High Energy Phys. 11 (2015) 160.]. Although the vector fields that generate the (generalized) BMS algebra at timelike infinity were defined in the literature, the algebra has not been investigated. In this paper. we fill this gap. We …

Association Of Hypothermia With Increased Mortality Rate In Sars-Cov-2 Infection, Naaz Fatteh, Glen E. Sutherland, Radleigh Santos, Rita Zeidan, Alexandra P. Gastesi, Christopher D. Naranjo

Mathematics Faculty Articles

Objective

We observed patients to have variable temperatures. The objective of the study was to identify if hypothermia in a patient infected with SARS-CoV-2 is associated with a higher than expected mortality.

Methods

We reviewed 331 charts from patients hospitalized with SARS-CoV-2 between March 9 to April 20, 2020.

Results

The probability of death was 2.06 times higher for those with hypothermia than those without [95% C.I. (1.25, 3.38)]. In ventilated patients, there were 32 deaths. Of those, 75% had been hypothermic. In a prior review of 10,000 non-SARS-CoV-2 patients with sepsis, the mortality rate in patients with hypothermia was …

In-Situ Imaging Of Surface Heterogeneity In Semiconductor Photocatalysts Using Singlemolecule Fluorescence Microscopy, Meikun Shen

Arts & Sciences Electronic Theses and Dissertations

Metal oxide semiconductors have been used as promising photocatalysts to convert solar energy into useful fuels, such as water splitting, carbon dioxide reduction, and nitrogen fixation reactions. However, the typical metal oxide photocatalysts' efficiency often suffers from their weak visible light absorption and low charge carrier mobilities. One common strategy to mitigate these limitations is to introduce oxygen vacancies into the lattice of the semiconductor photocatalysts. This strategy has been applied to many metal oxide photocatalysts, such as titanium oxide, tungsten oxide, and zinc oxide, and oxygen vacancies indeed enhance their catalytic activities. Various roles of oxygen vacancies have all …

Enhancing Infrasonic Signal Detection And Event Localization Through Advanced Computational Methods, Fransiska Dannemann Dugick

Earth Sciences Theses and Dissertations

The installation of worldwide infrasound and seismo-acoustic networks at both global and regional scales necessitates automated techniques and algorithms for accurate and efficient data processing and analysis. Signals recorded across the networks originate from a number of natural and anthropogenic sources. Data processing efforts focus on the separation of signals of interest from background noise, followed by the identification, or detection of signals of interest. Once signals are identified, association and location processing produces estimates of a signal's source. This dissertation focuses on the evaluation of automated processes for identifying and locating sources of interest.

Chapter two applies two state-of-the-art …

Understanding Impacts Of Urban Environments On Monitoring Infrasound To Low End Audible Acoustic Signals, Sarah Mccomas

Earth Sciences Theses and Dissertations

Infrasound arrays are traditionally installed in quiet rural settings, but there is a growing need in the infrasound community, tactical and nuclear monitoring, to understand the implications of moving arrays into or near populated areas. The tactical infrasound monitoring community is interested in monitoring higher frequency and/or low energy sources; this desire often requires a shorter source-receiver spacing. This limitation can move arrays out of more traditional rural spaces. In the nuclear monitoring community, this change is not a choice, but a forgone conclusion with arrays under construction or planed near populated areas such as Beijing, China and Teheran, Iran. …

Characterization Of Landslide Processes From Radar Remote Sensing And Hydromechanical Modeling, Yuankun Xu

Earth Sciences Theses and Dissertations

Landsides are a natural geomorphic process yet a dangerous hazard which annually causes thousands of casualties and billions of property loss in a global scale. Understanding landslide motion kinematics from early initiation to final deposition is critical for monitoring, assessing, and forecasting landslide movement in order to mitigate their hazards. Landslides occur under diverse environmental settings and appear in variable types; however, all types of landslides can be mechanically attributed to shearing failure at the basal surface due to stress regime shift contributed by internal and/or external forcing. Typical internal factors include soil/rock weathering, whereas typical external triggering forces encompass …

Cu-Promoted C-H Bond Hydroxylation Inspired By Cu-Dependent Metalloenzymes, Rachel Trammell

Chemistry Theses and Dissertations

From 2003 to 2015, Schӧnecker and Baran proposed a dinuclear Cu/O₂ species in their mechanistic proposal for the hydroxylation of sp³ C-H bonds within their systems (proposed based on yields). Inspired from the site selectivity of this methodology and poor analysis of the mechanism, the first project was inspired to re-examine the sp³ C-H bond hydroxylation by Schrӧnecker and Baran and perform an intensive investigation into understanding how Cu/O₂ interact which led us to propose a new mechanism based on the evidence collected (i.e., LCu^II-hydroperoxide species that undergoes homolytic O-O bond cleavage). From there …

Metal Salt Hydrolysis For Electrochemically Active Conducting Polymer Nanocomposites, Hongmin Wang

Arts & Sciences Electronic Theses and Dissertations

The diversity of nanostructures obtained from organic polymerization is limited when compared to the vast amount of inorganic nanostructures. This dissertation will focus on a synergistic mechanism between organic polymerization and in situ inorganic salt hydrolysis for developing electrochemically active organic-inorganic hybrid nanostructures. The degree of polymerization, crystallinity and doping level of the conjugated polymer backbone is controlled using oxidative radical vapor-phase polymerization resulting in organic semiconductors featuring high crystallinity and superior electrical conductivity. An aqueous metal salt solution of iron (III) chloride serves as an oxidant for initiating the polymerization and interestingly, this inorganic salt hydrolyzes in situ producing …

Targeted Combination Therapy Of Nsclc Using Taxol And Fingolimod Loaded Nanoceria, Raghunath Narayanam

Electronic Theses & Dissertations

Among various types of cancers, lung cancer reports highest death rate and Non-Small cell lung cancer causes highest mortality in lung cancers. This is mainly due to the scarcity of treatment options and the available treatment shows numerous adverse effects. In the recent times, nanotechnology paved a new path for the diagnosis and therapy of cancer. In this study, we worked on a novel, multifunctional nanoceria (NC) platform loaded with two unique drugs taxol and fingolimod, which acts in their own ways providing synergic therapeutic effect. We hypothesized that the usage of the polyacrylic acid (PAA) coated nanoceria (PNC) increases …

Morgan- Voyce Approach For Solution Bratu Problems, Bushra Eesa Kashiem

Emirates Journal for Engineering Research

Bratu equations are substantial in electrostatic and plasma problem. The aim of this paper is design a morgan-voyce approach for solving bratu problem. We present a morgan-voyce polynomial along with significant properties; the effectiveness of the proposed algorithm is demonstrated by considering three numerical examples.

Modeling Small Molecule Metabolism In Human Liver Microsome To Better Predict Toxicity Risk, Na Le Dang

Arts & Sciences Electronic Theses and Dissertations

Adverse drug reactions (ADRs) are a serious problem with increasing morbidity, mortality, and health care costs worldwide. In the U.S., ADRs are responsible for more than 50% of acute liver failure cases and are the fourth most common cause of death, costing 100,000 lives annually.Idiosyncratic adverse drug reactions (IADRs) are immune-mediated hypersensitivity ADRs that are difficult to foresee during drug development. IADRs are often caused by reactive metabolites produced during drug metabolism. These reactive metabolites covalently attach to cellular components, and the resulting conjugates may provoke toxic immune response. Because reactive metabolites are short-lived, they can be difficult to detect. …

Weighted Inequalities On Spaces Of Homogeneous Type, Naga Manasa Vempati

Arts & Sciences Electronic Theses and Dissertations

Let $(X,d,\mu )$ be a space of homogeneous type in the sense of Coifman andWeiss, i.e. $d$ is a quasi metric on $X$ and $\mu $ is a nonzero measure satisfying the doubling condition. Suppose that $u$ and $v$ are two locally finite positive Borel measures on $(X,d,\mu )$, the two weight inequality for the Calder\'on-Zygmund operator is of the form \begin{align*} & \|T(f\cdot u)\|_{L^2(v)}\lesssim \|f\|_{L^2(u)}. \end{align*} Subject to the pair of weights satisfying a side condition, we have given a characterization of the boundedness of a Calder\'{o}n-Zygmund operator $T$ from $L^{2}(u)$ to $L^{2}(v)$ in terms of the $A_{2}$ condition …

Synthesis And Characterization Of Putative Triplet Sensitizers In The Dark Pathway To Cyclobutane Pyrimidine Dimers Of Dna, Yanjing Wang

Arts & Sciences Electronic Theses and Dissertations

The cyclobutane pyrimidine dimer (CPD) is the major photoproduct resulting from direct absorption of UVB radiation in sunlight by DNA that results in C to T mutations found in human skin leading to skin cancer. CPDs can also be produced through the action of photosensitizers that can absorb longer wavelength UVA that is not absorbed efficiently by DNA and transfer triplet energy to the DNA. Most recently, CPDs was discovered to be formed in the dark following UV irradiation of melanocytes. This dark pathway was proposed to result from an indirect pathway to CPDs that involves triplet energy transfer from …

Machine Learning Methods For Depression Detection Using Smri And Rs-Fmri Images, Marzieh Sadat Mousavian

LSU Doctoral Dissertations

Major Depression Disorder (MDD) is a common disease throughout the world that negatively influences people’s lives. Early diagnosis of MDD is beneficial, so detecting practical biomarkers would aid clinicians in the diagnosis of MDD. Having an automated method to find biomarkers for MDD is helpful even though it is difficult. The main aim of this research is to generate a method for detecting discriminative features for MDD diagnosis based on Magnetic Resonance Imaging (MRI) data.

In this research, representational similarity analysis provides a framework to compare distributed patterns and obtain the similarity/dissimilarity of brain regions. Regions are obtained by either …

Aerosol Vapor Synthesis Of Organic Processable Pedot Particles And Measuring Electric Conductivity Using A 3d Printed Probe Station, Yang Lu

McKelvey School of Engineering Theses & Dissertations

Conducting polymers are organic semiconductors characterized by conjugated backbones (alternating single-double bonds) that enable mixed ionic-electronic conductivity. Their polymeric nature, tunable band structure and reversible redox capability have demonstrated fundamental advances in the fields ranging from electrochemical energy storage, sensing, to electro/photo catalysis and neuromorphic engineering. Conjugated backbones, the origin of all the unique physical and chemical properties associated with conducting polymers, prevent their solubility due to high lattice energy which hinders processing. Current solution utilizes a long-chain polymer (PSS) as dopants to render conducting polymer water dispersible (PEDOT:PSS). Nonetheless, PSS is highly acidic and hydrophilic limiting applicability with acid-incompatible …

Interaction Of Aqueous U(Vi) With Goethite, Montmorillonite, And Uo2(S), Anshuman Satpathy

McKelvey School of Engineering Theses & Dissertations

Uranium contamination in subsurface environments is a matter of great concern throughout the world. Fate and transport of uranium in the subsurface can be controlled by U(VI) adsorption and reduction onto common iron (oxy)hydroxides and clay minerals. Aqueous U(VI) can also exchange uranium atoms with solids comprised of uranium which can potentially lead to changes in the morphology of the uranium-containing solids and affect their stability. First, the performance of multiple surface complexation models (SCMs) on adsorption of U(VI) onto goethite was analyzed for a broad range of input conditions. Individual models could fit the data for which they were …

Partial Measurements Of Quantum Systems, Jonathan Tyler Monroe

Arts & Sciences Electronic Theses and Dissertations

Projective measurement is a commonly used assumption in quantum mechanics. However, advances in quantum measurement techniques allow for partial measurements, which accurately estimate state information while keeping the wavefunction intact. We employ partial measurements to study two phenomena. First, we investigate an uncertainty relation—in the style of Heisenberg’s 1929 thought experiment—which includes partial measurements in addition to projective measurements. We find that a weak partial measurement can decrease the uncertainty between two incompatible (non-commuting) observables. In the second study, we investigate the foundation of irreversible dynamics resulting from partial measurements. We do so by comparing the forward and time-reversed probabilities …

Assessment And Diagnosis Of Human Colorectal And Ovarian Cancer Using Optical Imaging And Computer-Aided Diagnosis, Yifeng Zeng

McKelvey School of Engineering Theses & Dissertations

Tissue optical scattering has recently emerged as an important diagnosis parameter associated with early tumor development and progression. To characterize the differences between benign and malignant colorectal tissues, we have created an automated optical scattering coefficient mapping algorithm using an optical coherence tomography (OCT) system. A novel feature called the angular spectrum index quantifies the scattering coefficient distribution. In addition to scattering, subsurface morphological changes are also associated with the development of colorectal cancer. We have observed a specific mucosa structure indicating normal human colorectal tissue, and have developed a real-time pattern recognition neural network to localize this specific structure …

A Collaborative Knowledge-Based Security Risk Assessments Solution Using Blockchains, Tara Thaer Salman

McKelvey School of Engineering Theses & Dissertations

Artificial intelligence and machine learning have recently gained wide adaptation in building intelligent yet simple and proactive security risk assessment solutions. Intrusion identification, malware detection, and threat intelligence are examples of security risk assessment applications that have been revolutionized with these breakthrough technologies. With the increased risk and severity of cyber-attacks and the distributed nature of modern threats and vulnerabilities, it becomes critical to pose a distributed intelligent assessment solution that evaluates security risks collaboratively. Blockchain, as a decade-old successful distributed ledger technology, has the potential to build such collaborative solutions. However, in order to be used for such solutions, …

Determining Biostratigraphy And Correlation Using Color Alteration Index And Lithofacies Of Conodonts In The Edinburg Formation, Central Virginia, Lauren Showalter

Senior Honors Projects, 2020-current

Conodont species, CAI and lithofacies analysis are used as methods of correlation to determine the relative age, depositional environment, and post depositional burial history of the Edinburg Formation in central Virginia. Samples collected for conodont microfossils yielded faunas of Baltoniodus sp. or Amorphognathus sp., Periodon grandis and Protopanderodus liripipus from a site near Luray and Drepanoistodus suberectus, Plectodina sp., Protopanderodus liripipus, Oistodus sp., Phragmodus undatus, Erismodus radicans and Panderodus gracilis from a site in Harrisonburg. The species supports a Late Ordovician (Late Sandbian age). Conodonts from both sites have a CAI of 4-5, indicating post-depositional heating of …

Integrated Mass Spectrometry-Based Method In Protein Chemistry: Metal-Binding Protein And Integral Membrane Protein, Chunyang Guo

Arts & Sciences Electronic Theses and Dissertations

Most biological processes are associated with protein catalysis. Characterizing protein structure, therefore, is crucial for understanding biological function. Mass spectrometry (MS)-based methods have emerged as a pivotal biophysical tool to interrogate protein structures; they can characterize protein-ligand/protein complexes that are refractory to conventional high-resolution means such as X-ray crystallography, Cryo-EM, and nuclear magnetic resonance (NMR) spectroscopy, in part owing to high molecular weight and significant flexibility. The integrated MS-based platform will provide topology and structural information of proteins from sketch to detail; native MS identifies protein complexes’ composition and stoichiometry; hydrogen-deuterium exchange MS (HDX-MS) detects the protein complexes’ dynamic change …

Supernova Neutrino Burst Detection With The Deep Underground Neutrino Experiment, B. Abi, R. Acciarri, M. A. Acero, G. Adamov, D. Adams, M. Adinolfi, Z. Ahmad, J. Ahmed, T. Alion, S. Alonso Monslave, C. Alt, J. Anderson, C. Andreopoulos, M. P. Andrews, F. Andrianala, S. Andringa, A. Ankowski, M. Antonova, S. Antusch, A. Aranda-Fernadez, Roberto Petti

Faculty Publications

The Deep Underground Neutrino Experiment (DUNE), a 40-kton underground liquid argon time projection chamber experiment, will be sensitive to the electronneutrino flavor component of the burst of neutrinos expected from the next Galactic core-collapse supernova. Such an observation will bring unique insight into the astrophysics of core collapse as well as into the properties of neutrinos. The general capabilities of DUNE for neutrino detection in the relevant few- to few-tens-of-MeV neutrino energy range will be described. As an example, DUNE’s ability to constrain the ν_e spectral parameters of the neutrino burst will be considered.

Differences In ​The Proportion Of Children Meeting Behavior Guidelines ​Between Summer ​And School By Socioeconomic Status And Race, Ethan T. Hunt, Lauren Von Klinggraeff, Alexis Jones, Sarah Burkart, Roddrick Dugger, Bridget Armstrong Ph.D., Michael Beets Ph.D., Gabrielle Turner-Mcgrievy Ph.D., Rd, Marco Geraci, Robert Glenn Weaver Med, Phd

Faculty Publications

Objective

Children who fail to meet activity, sleep, and screen-time guidelines are at increased risk for obesity. Further, children who are Black are more likely to have obesity when compared to children who are White, and children from low-income households are at increased risk for obesity when compared to children from higher-income households. The objective of this study was to evaluate the proportion of days meeting obesogenic behavior guidelines during the school year compared to summer vacation by race and free/reduced priced lunch (FRPL) eligibility.

Methods

Mixed-effects linear and logistic regressions estimated the proportion of days participants met activity, sleep, …

Real-Time Virtualization And Coordination For Edge Computing, Haoran Li

McKelvey School of Engineering Theses & Dissertations

Recent years have witnessed the emergence of edge computing as an enabling platform for time-sensitive services. However, existing edge computing platforms face a multitude of challenges in meeting the latency requirements of time-sensitive applications. (1) Traditional real-time virtualization platforms require offline configuration of the scheduling parameters of virtual machines (VMs) based on their worst-case workloads. However, this static approach results in pessimistic resource allocation when the workloads in the VMs change dynamically. (2) Edge computing operators must deliver consistent tail latency performance for time-sensitive applications deployed on different edge sites. Traditionally, significant effort is required to test, tune, and configure …

Towards Deploying Robust Machine Learning Systems, Liang Tong

McKelvey School of Engineering Theses & Dissertations

Machine learning (ML) has come to be widely used in a broad array of settings, including important security applications such as network intrusion, fraud, and malware detection, as well as other high-stakes settings, such as autonomous driving. A general approach is to extract a set of features, or numerical attributes, of entities in question, collect a training data set of labeled examples (for example, indicating which instances are malicious and which are benign), learn a model which labels previously unseen instances presented in terms of their extracted features, and then investigate alerts raised by instances predicted as malicious. Despite the …

Data Driven Architectural Geometric And Photometric Modeling, Huayi Zeng

McKelvey School of Engineering Theses & Dissertations

This thesis presents novel algorithms of architectural modeling, a crucial computer vision task to understand architectures by parsing visual input such as image or sensor data into digital representations. Compelling modeling algorithms serve as the fundamental block for a wide range of applications, including augmented reality, digital mapping, virtual simulation. While numerous handcrafted approaches have been proposed, the problem remains challenging in various difficult cases, such as occlusions and imperfect input. This dissertation studies four novel data-driven methods to perform high quality modeling. I first propose two geometric architectural modeling algorithms to recover the geometric primitives from aerial and facade …

Stochastic Goal Recognition Design, Christabel Wayllace

McKelvey School of Engineering Theses & Dissertations

Goal Recognition Design (GRD) is the problem of finding the least amount of environment modifications to force an acting agent to reveal its goal as early as possible. Figuring out an agent’s goal by observing its behavior is a problem studied in Psychology, Economics, and Artificial Intelligence, where it is known as goal recognition. Contrary to most common approaches where the focus is on finding faster algorithms to detect the goal, GRD takes an offline approach and focuses on environment design to facilitate goal recognition. This thesis investigates GRD problems when action outcomes are stochastic, which is the case of …

Ocean-Atmosphere Interactions During Hurricanes Marco And Laura (2020), Emily N. Eley, Bulusu Subrahmanyam, Corinne B. Trott

Faculty Publications

During August of the 2020 Atlantic Hurricane Season, the Gulf of Mexico (GoM) was affected by two subsequent storms, Hurricanes Marco and Laura. Hurricane Marco entered the GoM first (22 August) and was briefly promoted to a Category 1 storm. Hurricane Laura followed Marco closely (25 August) and attained Category 4 status after a period of rapid intensification. Typically, hurricanes do not form this close together; this study aims to explain the existence of both hurricanes through the analysis of air-sea fluxes, local thermodynamics, and upper-level circulation. The GoM and its quality of warm, high ocean heat content waters proved …