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Two Matrix-Weighted Norm Inequalities For Commutators With Fractional Integral Operators And Fractional Matrix-Weighted Dyadic Littlewood-Paley Theory, Roy Cardenas Dec 2022

Two Matrix-Weighted Norm Inequalities For Commutators With Fractional Integral Operators And Fractional Matrix-Weighted Dyadic Littlewood-Paley Theory, Roy Cardenas

Legacy Theses & Dissertations (2009 - 2024)

This thesis develops a fractional matrix-weighted John-Nirenberg type theorem, two matrix-weighted commutator bounds for the fractional integral operator, an Orlicz bumped two matrix-weighted commutator upper bound for the fractional integral operator, and a fractional matrix-weighted version of dyadic Littlewood-Paley theory.


Evaluating The Health Impacts Of Fruit And Vegetable Intake At The Individual Level And Food Pantry Level Among Food Pantry Users, Jiacheng Chen Dec 2022

Evaluating The Health Impacts Of Fruit And Vegetable Intake At The Individual Level And Food Pantry Level Among Food Pantry Users, Jiacheng Chen

Legacy Theses & Dissertations (2009 - 2024)

Background: Chronic diseases impose heavy burdens on individuals and the healthcare system in the US. Many factors were found to be associated with chronic diseases, including demographics, family history, social environmental factors, and individual behavioral factors such as diet and physical activity. Among those factors, fruit and vegetable intake can have substantial health impacts via a variety of causal pathways. Fruit and vegetable (F&V) consumption is generally lower among individuals living in households experiencing food insecurity and rely on food assistance programs. Decreased F&V intake among food pantry users may negatively impact health. However, conducting quantitative analysis on this population …


Motion Planning Under Uncertainties, Sourav Dutta Dec 2022

Motion Planning Under Uncertainties, Sourav Dutta

Legacy Theses & Dissertations (2009 - 2024)

A robot is an agent that can bring some changes to the environment around it. Motion planning is the problem of carrying out specialized tasks by a robot by either moving itself or some other object (usually called \textit{payload}) from one place to another. In a real-world scenario, a robot is faced with constraints such as momentum, friction, sensor inaccuracies, etc., that can affect its decision-making while performing specialized tasks. These constraints are identified as uncertainties, and successful planning involves making provisions for such uncertainties. In this work, we present methods like stochastic processes, sequential inference, and pattern recognition to …


Metabolic Alterations And Cardiovascular Risk After Hepatitis C Cure In Subjects With Or At Risk For Hiv, Christophe Maxime Fokoua Dongmo Dec 2022

Metabolic Alterations And Cardiovascular Risk After Hepatitis C Cure In Subjects With Or At Risk For Hiv, Christophe Maxime Fokoua Dongmo

Legacy Theses & Dissertations (2009 - 2024)

Background. Hepatitis C virus (HCV) infection engenders substantial metabolic changes. These changes are altered when the virus is cleared after successful treatment. We measured these metabolic alterations that occur after HCV cure; further, we assessed whether these alterations differed in subgroups defined by patients’ characteristics.


Probabilistic Forecasting Of Winter Mixed Precipitation Types In New York State Utilizing A Random Forest, Brian Chandler Filipiak Dec 2022

Probabilistic Forecasting Of Winter Mixed Precipitation Types In New York State Utilizing A Random Forest, Brian Chandler Filipiak

Legacy Theses & Dissertations (2009 - 2024)

Operational forecasters face a plethora of challenges when making a forecast; they must consider multiple data sources ranging from radar and satellites to surface and upper air observations, to numerical weather prediction output. Forecasts must be done in a limited window of time, which adds an additional layer of difficulty to the task. These challenges are exacerbated by winter mixed precipitation events where slight differences in thermodynamic profiles or changes in terrain create different precipitation types across small areas. In addition to being difficult to forecast, mixed precipitation events can have large-scale impacts on our society.


Characterization Of An Amine-Thiol Cosolvent System : Ethylenediamine And Mercaptoethanol, Fernanda Giongo Fernandes Dec 2022

Characterization Of An Amine-Thiol Cosolvent System : Ethylenediamine And Mercaptoethanol, Fernanda Giongo Fernandes

Legacy Theses & Dissertations (2009 - 2024)

Since its introduction, the amine-thiol cosolvent system has been successfully utilized for the deposition of various thin-film devices, but its mechanism of action is still uncertain. Herein, we have attempted to dissect some of the chemical characteristics of amine-thiol cosolvents, with a special interest taken towards a mixture of ethylenediamine (en) and mercaptoethanol (ME). Conductivity was measured for multiple amine-thiol combinations at different ratios to determine extent of ionization in solution, with en-ME having one of the highest solution conductivities. Exposing the solution to air for several days was found to decrease the conductivity of en-ME, indicating the formation of …


Probability Distributions Of The Scalar Potential, Candace Mathews Dec 2022

Probability Distributions Of The Scalar Potential, Candace Mathews

Legacy Theses & Dissertations (2009 - 2024)

In the study of cosmological inflation, string theory and supersymmetry have motivated a wide range of possible inflationary models. These models can be parameterized by a scalar potential V, which is a function of N scalar fields, and determines cosmological parameters such as the vacuum stability and energy density. In principle, we can determine V through high energy physics, such as string theory. In practice, though we may not know the details of V we might have clues about a distribution of plausible V’s, which we can build statistics on to further analyze. The purpose of this thesis defense is …


Large-Scale Flow Patterns Conducive To Central American Extreme Precipitation Events During Autumn, Alexander Kyle Mitchell Dec 2022

Large-Scale Flow Patterns Conducive To Central American Extreme Precipitation Events During Autumn, Alexander Kyle Mitchell

Legacy Theses & Dissertations (2009 - 2024)

Extreme precipitation events (EPEs), characterized by daily widespread heavy rainfall exceeding the 95th percentile across Central America, can have large impacts on agriculture, life, and property during the rainy season. EPEs during the Northern Hemisphere (NH) autumn, however, have been observed to be influenced by both tropical and extratropical originating phenomena such as easterly waves and cold surges, respectively. Given the limited research in this area, the novelty of this work is to apply a systematic approach for identifying and better understanding EPEs, and investigating their associated synoptic-scale variability using daily high-resolution observations and reanalysis products over Central America. An …


Turning Density Functional Theory Calculations Into Molecular Mechanics Simulations : Establishing The Fluctuating Density Model For Rna Nucleobases, Christopher A. Myers Dec 2022

Turning Density Functional Theory Calculations Into Molecular Mechanics Simulations : Establishing The Fluctuating Density Model For Rna Nucleobases, Christopher A. Myers

Legacy Theses & Dissertations (2009 - 2024)

Molecular mechanics (MD) simulations and density functional theory (DFT) have been the backbone of computational chemistry for decades. Due to its accuracy and computational feasibility, DFT has become the go-to method for theoretically predicting interaction energies, polarizability, and other electronic properties of small molecules at the quantum mechanical level. Although less fundamental than DFT, molecular mechanics (MM) algorithms have been just as influential in the fields of biology and chemistry, owing their success to the ability to compute measurable, macroscopic quantities for systems with tens of thousands to hundreds of thousands of atoms at a time. Nevertheless, MD simulations would …


Soil From Footwear Is A Newly Rediscovered Type Of Forensic Evidence Due To The Application Of Modern Analytical Techniques : A Review, Rhilynn Haley Ogilvie Dec 2022

Soil From Footwear Is A Newly Rediscovered Type Of Forensic Evidence Due To The Application Of Modern Analytical Techniques : A Review, Rhilynn Haley Ogilvie

Legacy Theses & Dissertations (2009 - 2024)

Traces of soil discovered on a footwear were historically among the first types of evidence used by crime scene investigators. This type of evidence has been rediscovered recently due to the application of powerful analytical techniques providing quantitative characteristics of the soil (bio)chemical composition. Advanced statistical analysis of the quantitative data further improves the probative value of the soil evidence. The article overview main aspects of the emerging techniques for the forensic soil analysis and the factors that challenge data interpretation including mixing, contamination, and composition complexity. Overcoming these issues is crucial for utilizing soil analysis for forensic purposes.


Comparison Of 2018-2021 Tropical Cyclone Track Forecasts Before And After Noaa G-Iv Missions, Melissa Piper Dec 2022

Comparison Of 2018-2021 Tropical Cyclone Track Forecasts Before And After Noaa G-Iv Missions, Melissa Piper

Legacy Theses & Dissertations (2009 - 2024)

Tropical cyclone (TC) hazards are primarily dictated by the TC position; thus, it is important to produce accurate TC track forecasts. Many different features can influence a TC’s motion, yet these features are not always well sampled by in-situ observations over the open ocean, creating a need for supplemental observation collected via aircraft, including the deployment of dropsondes. In 1997, the National Hurricane Center (NHC) began operational synoptic surveillance missions in the near-storm environments of TCs using the Gulfstream IV-SP jet aircraft (G-IV), with the goal of reducing track forecast errors. In the first 10 years of operational missions, the …


Development Of Nucleic Acid Diagnostics For Targeted And Non-Targeted Biosensing, Christopher William Smith Dec 2022

Development Of Nucleic Acid Diagnostics For Targeted And Non-Targeted Biosensing, Christopher William Smith

Legacy Theses & Dissertations (2009 - 2024)

The field of nucleic acid technology is rapidly expanding with new impactful discoveriesbeing made each year. Starting from the discovery of the double-helix structure, cloning, gene editing, polymerase chain reaction (PCR), CRISPR technology, and even the late mRNA vaccines; nucleic acid technology is at the forefront of improving medicine. Nucleic acid technology is extremely versatile due to its easy programmability, automated cheap synthesis, and even its catalog for numerous chemical modifications that can be used to alter structure stability. For example, the number of permutations that can be made with DNA just by altering the code for adenine (A), cytosine …


The Simulated Sensitivity Of The North American Monsoon At Convection-Permitting Scales, Brendan Wallace Dec 2022

The Simulated Sensitivity Of The North American Monsoon At Convection-Permitting Scales, Brendan Wallace

Legacy Theses & Dissertations (2009 - 2024)

The North American Monsoon (NAM) is a major contributor to annual rainfall for large portions of the North American Southwest. Much of the prior work examining the NAM using numerical models has been done at scales exceeding 20-km grid spacing. At these coarse scales, unresolved processes and poorly resolved geographic features can impact model performance. This can present a problem when simulating the NAM particularly with regard to orographic precipitation, precipitation on sub-daily timescales, and land surface-atmosphere interactions. This dissertation seeks to better understand the NAM through examination of several sets of convection-permitting regional climate model output. The primary goal …


Deep Active Genetic Learning With Evidential Uncertainty For Agriculture Crops And Lake Water Quality Assessment, Oguz M. Aranay Aug 2022

Deep Active Genetic Learning With Evidential Uncertainty For Agriculture Crops And Lake Water Quality Assessment, Oguz M. Aranay

Legacy Theses & Dissertations (2009 - 2024)

Despite significant advancements in the field of machine learning, there are two issues that still require further exploration. First, how to learn from a small dataset; and second, how to select appropriate features from the data. Although there exist many techniques to address these issues, choosing a combination of the techniques from these two groups is challenging, and worth investigating. To address these concerns, this thesis presents a learning framework that is based on a deep learning model utilizing active learning (with evidential uncertainty as a basis for acquisition function) for the first issue and a genetic algorithm for the …


Frameworks For Secure Collaborative And Concurrent Editing, Shashank Arora Aug 2022

Frameworks For Secure Collaborative And Concurrent Editing, Shashank Arora

Legacy Theses & Dissertations (2009 - 2024)

Cloud-based online document editing services, such as Google Docs and Office 365, provide an inexpensive and efficient means of managing documents. However, storing data on the cloud also raises certain security and privacy concerns, especially when the data is of confidential and sensitive nature. Storing data on third-party servers can potentially be compromising as it gives an opportunity to the third-party cloud service providers to turn semi-honest and become curious about user data. User data stored on third-party servers is also prone to attacks like virtual machine-based side-channel along with natural language processing and machine learning-based content search and retrieval …


An Ims-Ms/Md Workflow For Determining Higher Order Structure And Dynamics Of Nucleic Acids, Rebecca D'Esposito Aug 2022

An Ims-Ms/Md Workflow For Determining Higher Order Structure And Dynamics Of Nucleic Acids, Rebecca D'Esposito

Legacy Theses & Dissertations (2009 - 2024)

Ion mobility spectrometry - mass spectrometry (IMS-MS) has potential for the investigation of structure and dynamics in large biopolymers, which will come to full fruition only with a firmer understanding of how to interpret the experimental data. Numerous studies have employed elements of nucleic acid (NA) secondary structure, such as duplexes and hairpins, to explore the relationships between structure, experimental conditions, and actual observations. When combined with molecular dynamics simulations (MDS), IMS-MS can be effectively employed to perform structural elucidation of biomolecules that are not readily amenable to established techniques employed for structural analysis.


Human-Wildlife Coexistence With Coyotes In Los Angeles County, Ca And Cook County, Il, Alan Eapen Aug 2022

Human-Wildlife Coexistence With Coyotes In Los Angeles County, Ca And Cook County, Il, Alan Eapen

Legacy Theses & Dissertations (2009 - 2024)

The expansion of coyotes (Canis latrans) into urban and suburban areas where human concentration is high has led to human-coyote conflicts often leading to increased management actions against coyotes. Recently in Los Angeles and Cook Counties, municipalities have developed coyote management plans to foster human-wildlife coexistence in an effort to reduce conflict, an emerging concept that promotes the cohabitation of humans and animals in shared landscapes. The thesis investigates coyote management plans and policies concerning human-coyote interactions in Los Angeles and Cook Counties to address human-wildlife. Using a case study analysis of Los Angeles and Cook Counties, this study analyzed …


Examining The Impact Of Stratospheric Vortex Variability On Us Surface Temperature, Elena M. Fernandez Aug 2022

Examining The Impact Of Stratospheric Vortex Variability On Us Surface Temperature, Elena M. Fernandez

Legacy Theses & Dissertations (2009 - 2024)

Variability in high-latitude stratospheric flow, including major sudden stratospheric warming (SSW) or strong polar vortex events, can modulate tropospheric circulation and have meteorological implications on surface temperature and weather. The largest tropospheric impacts from Northern Hemisphere stratospheric variability – and the regions of focus in the literature – are observed in the North Atlantic, Europe and Asia. Impacts on North America occur but have received less research attention. The goal of this thesis research is to identify and quantify the relationship between high-latitude stratospheric variability and North American wintertime temperature.Using the ERA-Interim and ERA-5 reanalysis for the period of 1999/2000–2018/19, …


A Comparative Analysis Of The Impact Of Low-Level Jets And Atmospheric Rivers In The Central U.S, Nabindra Gyawali Aug 2022

A Comparative Analysis Of The Impact Of Low-Level Jets And Atmospheric Rivers In The Central U.S, Nabindra Gyawali

Legacy Theses & Dissertations (2009 - 2024)

Atmospheric Rivers (AR) are the primary source of poleward moisture transport globally. In theUnited States, much recent attention has been placed on Pacific Coast ARs which occur between December and March. However, the central US is also substantially impacted by warm-season AR. An open question is whether these warm-season ARs are synonymous with Great Plains low-level jets (LLJs) that have long served as a focal point of mesoscale atmospheric research. In this study, we perform a comparative analysis of ARs and LLJs in the central U.S using ECMWF’s climate-quality reanalysis of the 20th century, CERA-20C. The aim is to identify …


Changes In Large-Scale Extreme Precipitation In Over Taiwan And The Northeast United States : Past And Future, Lexi Henny Aug 2022

Changes In Large-Scale Extreme Precipitation In Over Taiwan And The Northeast United States : Past And Future, Lexi Henny

Legacy Theses & Dissertations (2009 - 2024)

Large-scale extreme precipitation over (1) the mid-Atlantic and Northeast United States and (2) Taiwan is attributed to weather types such as atmospheric river (AR), TC, and extreme integrated vapor transport (IVT). Statistically significant increases in season-total EP day precipitation are seen at many GHCN stations in winter, summer, and fall in the mid-Atlantic and Northeast region, and at certain high-elevation grid points in Taiwan Mei-yu season. During the cold season of winter and spring, the U.S.-based changes come from AR-associated EP days and are associated with strengthened southwesterly winds and IVT either within EP days, in the season mean, or …


Multiple Imputation In High-Dimensional Data With Variable Selection, Qiushuang Li Aug 2022

Multiple Imputation In High-Dimensional Data With Variable Selection, Qiushuang Li

Legacy Theses & Dissertations (2009 - 2024)

This dissertation focuses on the development of multiple imputation models and algorithms for high-dimensional data with variable selection structures. Leveraging on the multivariate linear mixed-effects model with missing responses for clustered data, we incorporate the variable selection routines using spike-and-slab priors within the Bayesian variable selection framework. Specific choice of these priors allow us to "force'' variables of importance (e.g. design variables or variables known to play role in missingness mechanism) into the imputation models. Our ultimate goal is to improve computational speed by removing unnecessary variables. Markov chain Monte Carlo techniques have been designed to sample from the implied …


Amyloid Fibril Formation And Polymorphism : A Critical Role Of Sulfur-Containing Amino Acid Residues, Tatiana Quiñones-Ruiz Aug 2022

Amyloid Fibril Formation And Polymorphism : A Critical Role Of Sulfur-Containing Amino Acid Residues, Tatiana Quiñones-Ruiz

Legacy Theses & Dissertations (2009 - 2024)

Protein aggregation that results in the formation of amyloid fibrils has been linked to many neurodegenerative disorders, including Alzheimer’s disease and Parkinson’s disease. The sulfur atoms in methionine (Met) and cysteine (Cys) residues of proteins can be readily oxidized, significantly affecting their properties. Oxidation of sulfur-containing amino acids has recently been shown to affect protein fibrillation. This work presents novel findings on Cys and Met redox reactions that are related to the formation of amyloid fibrils and on the polymorphism of a model fibrillogenic protein, hen egg white lysozyme (HEWL). Biophysical techniques including Raman spectroscopy, atomic force microscopy, electron paramagnetic …


Presto : Fast And Effective Group Closeness Maximization, Baibhav L. Rajbhandari Aug 2022

Presto : Fast And Effective Group Closeness Maximization, Baibhav L. Rajbhandari

Legacy Theses & Dissertations (2009 - 2024)

Given a graph and an integer k, the goal of group closeness maximization is to find, among all possible sets of k vertices (called seed sets), a set that has the highest group closeness centrality. Existing techniques for this NP-hard problem strive to quickly find a seed set with a high, but not necessarily the highest centrality.


Calculational Methods In Conformal Field Theory, Thomas Andrew Vandermeulen Aug 2022

Calculational Methods In Conformal Field Theory, Thomas Andrew Vandermeulen

Legacy Theses & Dissertations (2009 - 2024)

We examine conformal field theories and their gaugings (orbifolds), first on the torus and then on surfaces of higher genus. Specific attention is paid to performing explicit calculations, to which end we introduce a number of specialized formalisms. Namely, the technology of flavored partition functions allows for a general treatment of orbifolds in theories with conserved currents, and Arakelov geometry facilitates the derivation of novel expressions for geometric quantities appearing commonly on higher genus worldsheets. Ultimately, we leverage the resulting expressions in the calculation of correlation functions via degeneration of Riemann surfaces.


Computational Methods For Propagation Of Optical Fields With The Angle-Impact Wigner Function, Jeremy Wittkopp Aug 2022

Computational Methods For Propagation Of Optical Fields With The Angle-Impact Wigner Function, Jeremy Wittkopp

Legacy Theses & Dissertations (2009 - 2024)

In designing an optical setup for an experiment, one usually turns to simulations first in order to model the propagation of light through the proposed system. This way, the experimenter can determine if the system is operating as intended. In order for these simulations to be useful, they need to properly describe the propagation of light. In order to simplify calculations, most contemporary software makes assumptions on the nature of the light being propagated. Specifically, simulations typically consider optical fields that are beam-like (i.e., most of the rays comprising the field deviate only slightly in angle from the beam's primary …


Stability And Differential Privacy Of Stochastic Gradient Methods, Zhenhuan Yang Aug 2022

Stability And Differential Privacy Of Stochastic Gradient Methods, Zhenhuan Yang

Legacy Theses & Dissertations (2009 - 2024)

Recently there are a considerable amount of work devoted to the study of the algorithmic stability as well as differential privacy (DP) for stochastic gradient methods (SGM). However, most of the existing work focus on the empirical risk minimization (ERM) and the population risk minimization problems. In this paper, we study two types of optimization problems that enjoy wide applications in modern machine learning, namely the minimax problem and the pairwise learning problem.


High-Capacity And Interpretable Temporal Point Process Models For User Activity Sequence Modeling, Mengfan Yao Aug 2022

High-Capacity And Interpretable Temporal Point Process Models For User Activity Sequence Modeling, Mengfan Yao

Legacy Theses & Dissertations (2009 - 2024)

A temporal point process can be viewed as a collection of random points falling in the space of time, which is a special type of stochastic processes that is used to model complex event sequences in continuous time.As event data has become more widely available, temporal point process models (TPPs), i.e. techniques for modeling temporal point processes, have been used to solve a wide range of real-world problems, in domains such as e-commerce, online education, and social media. Motivated by the limitations in TPP literature, this dissertation aims to explore and study the following research questions: 1) Focusing on the …


Probing The Stability And Solution Processability Of Metal Chalcogenide Semiconducting Materials, Mengwen Yan Jul 2022

Probing The Stability And Solution Processability Of Metal Chalcogenide Semiconducting Materials, Mengwen Yan

Legacy Theses & Dissertations (2009 - 2024)

Metal chalcogenide (MCh) semiconductors have long research history due to their earth abundance, easy synthesizability, and accessible band gap tunability. People have realized their functionality as p-type semiconductors that provide good hole mobility and conductivity within the materials. However, MChs have easier reaction pathway with gas molecules (H2O and O2) compared to other semiconductors such as metal oxides. Also, poor solution processability of all MChs make low-cost thin film fabrication methods hard to achieve. In this thesis, we target to understand both the chemical stability and solution processability of MCh materials. ZnSe based inorganic organic layered hybrids (LHs) were exfoliated …


Permaculture As An Ecopedagogy Curriculum And Alternative Theory Of Development : An Exploration Of The Ecological Consciousness Of Rural Western Kenyan Farmers Using Photo-Voice With A Farmer Field School During Covid-19, David Yisrael Epstein May 2022

Permaculture As An Ecopedagogy Curriculum And Alternative Theory Of Development : An Exploration Of The Ecological Consciousness Of Rural Western Kenyan Farmers Using Photo-Voice With A Farmer Field School During Covid-19, David Yisrael Epstein

Legacy Theses & Dissertations (2009 - 2024)

This dissertation explores two main questions of farmers in Western Kenya – how they see farming as a creative process and their role in that – and how change is made possible in their community. I explore stories from farmers themselves, using photographs they have taken and stories they tell about those photographs, which answer these two questions. In doing so, I attempt to understand the degree to which collective action has taken root in a community exposed to a permaculture based curriculum within a farmer field school. It also importantly seeks to understand what happens when such a curriculum …


Exposing Gan-Generated Faces Using Deep Neural Network, Hui Guo May 2022

Exposing Gan-Generated Faces Using Deep Neural Network, Hui Guo

Legacy Theses & Dissertations (2009 - 2024)

Generative adversarial network (GAN) generated high-realistic human faces are visually challenging to discern from real ones. They have been used as profile images for fake social media accounts, which leads to high negative social impacts.In this work, we explore a universal physiological cue of the eye, namely the pupil shape consistency, to identify GAN-generated faces reliably. We show that GAN-generated faces can be exposed via irregular pupil shapes. This phenomenon is caused by the lack of physiological constraints in the GAN models. We demonstrate that such artifacts exist widely in high-quality GAN-generated faces. We design an automatic method to segment …