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Full-Text Articles in Physical Sciences and Mathematics

Hydrogel And Soluble Polymers To Support Metal Ion Chemosensors, Rebecca Adel Dominguez May 2023

Hydrogel And Soluble Polymers To Support Metal Ion Chemosensors, Rebecca Adel Dominguez

Theses and Dissertations

Most water systems contain metal ions. Some of these ions, such as lead, arsenic, and mercury, are extremely toxic. It is of great concern when those ions make their way into drinking water. There is a need for a device that can detect small amounts of dissolved metal ions in real-time. The Schwabacher group has designed such a device, based on azo dyes as the chemo sensors that change color in the presence of metal ions. These sensors can detect very small concentrations of metal ions into the parts per billion range. The sensor dyes are connected with covalent bonds …


Cosmology, Lensing, And Modified Gravity With Gravitational Waves, Ignacio Magana Hernandez May 2023

Cosmology, Lensing, And Modified Gravity With Gravitational Waves, Ignacio Magana Hernandez

Theses and Dissertations

Since the first detection of gravitational waves (GWs) from the merger of two stellar-mass black holes in 2015, the LIGO-Virgo-KAGRA (LVK) Collaboration has accumulated over 90 observations of mergers involving neutron stars and black holes. With the upcoming observing runs for the LVK network of GW detectors, many more binary mergers are expected to be detected. The increasing size of gravitational wave catalogs has enabled the study of their population, its cosmic expansion history, signatures of gravitational wave lensing, and how well these observations agree with general relativity. In this dissertation, I will discuss my contributions to gravitational wave cosmology. …


Utilizing Fluorescent Nanoscale Particles To Create A Map Of The Electric Double Layer, Quintus Owen May 2023

Utilizing Fluorescent Nanoscale Particles To Create A Map Of The Electric Double Layer, Quintus Owen

Theses and Dissertations

The interactions between charged particles in solution and an applied electric field follow several models, most notably the Gouy-Chapman-Stern model, for the establishment of an electric double layer along the electrode, but these models make several assumptions of ionic concentrations and an infinite bulk solution. As more scientific progress is made for the finite and single molecule reactions inside microfluidic cells, the limitations of the models become more extreme. Thus, creating an accurate map of the precise response of charged nanoparticles in an electric field becomes increasingly vital. Another compounding factor is Brownian motion’s inverse relationship with size: large easily …


Impact Of The Pre-A Motif On Truncated Hemoglobin N Activity, Alexander Shayne Drena May 2023

Impact Of The Pre-A Motif On Truncated Hemoglobin N Activity, Alexander Shayne Drena

Theses and Dissertations

Tuberculosis (TB) remains the leading cause of death by an infectious agent and therefore a global health crisis, according to the most recent report by the World Health Organization. This is due, in part, to Mycobacterium tuberculosis’ impressive defensive mechanisms against immune response, as well as the rise of Multi-Drug Resistant strains that have recently developed. Towards the turn of the century, a small heme protein called truncated hemoglobin N (trHbN) was discovered to protect the bacteria against reactive nitrogen species by converting nitric oxide (NO) to nitrate at rates far exceeding those of myoglobin and closer to those of …


Emotion Classification And Intensity Prediction On Tweets, Sharath Chander Pugazhenthi May 2023

Emotion Classification And Intensity Prediction On Tweets, Sharath Chander Pugazhenthi

Theses and Dissertations

The task of finding an emotion associated with the text from individuals on a social media platform has become very crucial as it influences the current state of mind of a particular individual in real life. It also helps one to understand social behavior at a given point in time. Microblogging platforms like Twitter serves as a powerful tool for expressing one’s thoughts. Several work have been done in classifying the emotion associated with it. The thesis comprises of a system that first classifies the tweet into one of the four emotions - anger, joy, sadness, and fear with good …


Future Of Functional Reactive Programming In Real-Time Systems, Anisha Tasnim May 2023

Future Of Functional Reactive Programming In Real-Time Systems, Anisha Tasnim

Theses and Dissertations

The evolution of programming paradigms and the development of new programming languages are driven by the needs of problem domains. Functional reactive programming (FRP) combines functional programming (FP) and reactive programming (RP) concepts that leverage asynchronous dataflow from reactive programming and higher-level abstractions building blocks from functional programming to enable developers to define data flows and transformations declaratively. Declarative programming allows developers to concentrate more on the problem to be solved rather than the implementation details, resulting in efficient and concise code. Over the years, various FRP designs have been proposed in real-time application areas. Still, it remains unclear how …


Modeling Wlan Received Signal Strengths Using Gaussian Process Regression On The Sodindoorloc Dataset, Fabian Hermann Josef Fuchs May 2023

Modeling Wlan Received Signal Strengths Using Gaussian Process Regression On The Sodindoorloc Dataset, Fabian Hermann Josef Fuchs

Theses and Dissertations

While any wireless technology can be used for indoor localization purposes, WLANhas the advantage of having a huge existing infrastructure. A radio map that matches specific locations to received signal strength is needed, to enable most of these indoor localization methods. To create these radio maps, with enough detail to achieve sufficient localization accuracy, is expensive and time consuming. Therefore, methods to interpolate and extrapolate more detailed maps from sparse radio maps are being developed. One recent approach is to use Gaussian process regression. Even though some papers already studied Gaussian process regression, most studied only the basic model with …


Modeling Brain Tumor Dynamics With The Help Of Cellular Automata, Paula Kathrin Viktoria Jaki May 2023

Modeling Brain Tumor Dynamics With The Help Of Cellular Automata, Paula Kathrin Viktoria Jaki

Theses and Dissertations

Primary brain tumors pose a serious threat to a person’s health. Gaining a deeper understanding of the dynamics of tumor growth is crucial for developing a proper treatment plan. Many computational models have been suggested to investigate the interaction between tumor cells and their surroundings. Using cellular automata is particularly promising since it integrates the features of self-organizing complex systems which allows them to properly depict local interactions between cells. The foundation of the thesis lies in the model proposed by Kansal et al. It uses four microscopic parameters, the maximum tumor extent, the base proliferative and necrotic thickness as …


Numerical Study Of A One-Dimensional Poisson-Nernst–Planck Ion Channel Model By Finite Element Backward And Forward Euler Methods, Michel Stanislas Korfhage May 2023

Numerical Study Of A One-Dimensional Poisson-Nernst–Planck Ion Channel Model By Finite Element Backward And Forward Euler Methods, Michel Stanislas Korfhage

Theses and Dissertations

This thesis presents a numerical study of a one-dimensional Poisson-Nernst-Planck (PNP) ion channel model,which describes the transport of charged species in an electrolyte under the influence of an electric field. We develop a new numerical scheme for solving the PNP model by combining the method of lines with the finite element and Euler's forward and backward methods. We then implement the scheme based on the finite element library from the FEniCS project. To validate the accuracy of our numerical scheme, we construct an analytical solution of the PNP model with source terms. We find in numerical tests that the backward …


Entangled Conquest: A Study Of Cultural Hybridization And Change In Norman Ireland, Sean Mcconnel May 2023

Entangled Conquest: A Study Of Cultural Hybridization And Change In Norman Ireland, Sean Mcconnel

Theses and Dissertations

This thesis employs entanglement theory and new geophysical macro-analytical methods to

examine the spread of Norman culture in late medieval Ireland. The traditional theories of

Anglo-Norman conquest by mass migration, by military conquest, and by political conquest are

reviewed and compared to a more nuanced theory of Normanization, which suggests that

genetically Irish people, who spoke Irish, practiced Irish law, and pursued Irish interests were

primarily responsible for what is considered "Norman" material culture on the Island. This

dissertation presents the idea that adherence to the English king was a necessary and expedient

action on the part of Irish lords …


Nonlinear Mathematical Transformations For Improved Image And Signal Recovery Using Artificial Neural Network, Haoran Chang May 2023

Nonlinear Mathematical Transformations For Improved Image And Signal Recovery Using Artificial Neural Network, Haoran Chang

Theses and Dissertations

Medical imaging plays a vital role in modern healthcare, enabling clinicians to diagnose and treat a range of conditions. However, image acquisition and processing can be challenging because they can often be hindered by motion blurring, leading to inaccurate results. To address that, this dissertation proposes a novel approach based on nonlinear mathematical transformations and artificial neural networks (ANN). The dissertation begins with an introduction to Nuclear Medicine and the problem of motion blur in image reconstruction. A background on Medical Imaging techniques, including the Radon transform and Image Reconstruction methods such as Filtered Back Projection and Iterative Reconstruction methods …


A Machine Learning Approach To Evaluate The Effect Of Sodium-Glucose Cotransporter-2 Inhibitors On Chronic Kidney Disease In Diabetes Patients, Solomon Eshun May 2023

A Machine Learning Approach To Evaluate The Effect Of Sodium-Glucose Cotransporter-2 Inhibitors On Chronic Kidney Disease In Diabetes Patients, Solomon Eshun

Theses and Dissertations

Chronic kidney disease (CKD) is a significant complication that contributes to diabetes-related mortality in the United States, and there is growing evidence that sodium-glucose cotransporter 2 inhibitors (SGLT2i) can slow its progression. However, observational studies may suffer from confounding by indication, where patient characteristics and disease severity influence the decision to prescribe SGLT2i. This study utilized electronic health records of individuals with diabetes (from TriNetX) to investigate the effectiveness of SGLT2i on CKD progression. The database provided detailed information on patients’ CKD status, demographics, diagnosis, procedures, and medications, along with corresponding dates of diagnosis and prescription. The study comprised of …


Results And Simulation Of Active Self-Assembly, Robert M. Alaniz May 2023

Results And Simulation Of Active Self-Assembly, Robert M. Alaniz

Theses and Dissertations

Self-assembly is the process by which simple elements in a system organize themselves into more complex structures based on a set of rules that govern their interactions. With many ways to create self-assembling systems, new models of abstraction have also arisen to handle specific mechanisms and procedures. We explore several open problems in the seeded model of Active Self-Assembly, Chemical Reaction Networks, and Surface Chemical Reaction Networks, proving new results while developing a robust simulation environment, AutoTile, to help build and test these results.


An Investigation Into Optimal Descent Trajectories For Multipurpose Long Range Space Vehicles Under Advanced Conditions, John M. Levis May 2023

An Investigation Into Optimal Descent Trajectories For Multipurpose Long Range Space Vehicles Under Advanced Conditions, John M. Levis

Theses and Dissertations

In this work, we investigate the problem of fuel-optimal control of space vehicle descent trajectories. The main tool we use to establish optimality is Pontryagin’s Maximum Principle. We present a variety of scenarios with increasing complexities, including drag, wind, and moving landing platforms in the context of differing atmospheric and gravitational conditions. Throughout the paper, we use a balance of analytical and numerical techniques. Finally, observations and conclusions drawn from the investigation form the basis for suggestions into additional areas of analysis.


An Analysis Of Antichimeral Ramanujan Type Congruences For Quotients Of The Rogers-Ramanujan Functions, Ryan A. Mowers May 2023

An Analysis Of Antichimeral Ramanujan Type Congruences For Quotients Of The Rogers-Ramanujan Functions, Ryan A. Mowers

Theses and Dissertations

This paper proves the existence of antichimeral Ramanujan type congruences for certain modular forms These modular forms can be represented in terms of Klein forms and the Dedekind eta function. The main focus of this thesis is to introduce the necessary theory to characterize these specific Ramanujan type congruences and prove their antichimerality.


Self-Supervised Representation Learning For Motion Time Series: A Case Study In Activity Recognition, Luis Carlos Garza Perez May 2023

Self-Supervised Representation Learning For Motion Time Series: A Case Study In Activity Recognition, Luis Carlos Garza Perez

Theses and Dissertations

In this thesis we will learn about what contrastive learning and time series are and understand the differences between supervised and self-supervised frameworks in machine learning. In addition, we will describe how the newest and most efficient self-supervised learning framework for visual representations to this date works, called SimCLR, which was originally developed to obtain useful vector representations from static images. We will also explain what TS2Vec is, and how a combination of both approaches can be applied to the concept of a time series, and still be able to extract a vector representation of the subject described by the …


Data Science For Hospital Antibiotic Stewardship, Saikou Jawla May 2023

Data Science For Hospital Antibiotic Stewardship, Saikou Jawla

Theses and Dissertations

Antibiotics are widely used to treat bacterial infections, but their misuse leads to antibiotic resistance. Antibiotic resistance is one of the biggest threats to global health, food security, and development today. Antibiotic resistance leads to higher medical costs, prolonged hospital stays, and increased mortality. Antimicrobial stewardship is an approach to measure and improve the appropriate use of antibiotics in healthcare settings. Data science has the potential to support these programs by providing insights into antibiotic prescribing patterns, identifying areas for improvement, and predicting patient outcomes. We explored the role of data science in hospital antibiotic stewardship programs, including statistical methods …


Congruences For Quotients Of Rogers-Ramanujan Functions, Maria Del Rosario Valencia Arevalo May 2023

Congruences For Quotients Of Rogers-Ramanujan Functions, Maria Del Rosario Valencia Arevalo

Theses and Dissertations

In 1919 the mathematician Srinivasa Ramanujan conjectured congruences for the partition function p(n) modulo powers of the primes 5,7,11. In this work, we study Ramanujan type congruences modulo powers of primes p = 7,11,13,17,19,23 satisfied by the Fourier coefficients of quotients the Rogers-Ramanujan Functions G(τ) and H(τ) and the Dedekind eta function η(5τ). In addition to deriving new congruences, we develop the foundational theory of modular forms to motivate and prove the results. The work includes proofs of congruences facilitated by Python/SageMath code.


Elucidating Unique Sources And Persistent Hydrologic Pathways Of Chloride To Perennial Freshwater Streams: Root River Analog In A Cold-Weather Environment, Leah Elizabeth Dechant May 2023

Elucidating Unique Sources And Persistent Hydrologic Pathways Of Chloride To Perennial Freshwater Streams: Root River Analog In A Cold-Weather Environment, Leah Elizabeth Dechant

Theses and Dissertations

Chloride in freshwater streams is increasing in concentration, persisting throughout the year, and contributing to the salinization of water resources. The primary source and pathway of chloride in cold-weather environments are thought to be road salt and runoff. However, mounting evidence displays that other sources and pathways of chloride play an important role yet studies to elucidate them at a high resolution, both temporally and spatially, and across diverse land use are lacking. In this study, chloride was quantified continuously for an urban and rural stream year-round in a watershed thought to be heavily impacted by road salt. Bivariate mixing …


Relative Eruption Chronology And Tephra-Vent Correlations Of The Sand Mountain Volcanic Field, Oregon High Cascades, Adam S. Chumley May 2023

Relative Eruption Chronology And Tephra-Vent Correlations Of The Sand Mountain Volcanic Field, Oregon High Cascades, Adam S. Chumley

Theses and Dissertations

Tephra stratigraphy east of the SMVF was sampled to characterize the major and trace element geochemistry, along with olivine and plagioclase mineral chemistry, in attempts to correlate the tephra with specific cones and cone groups in the SMVF chain. Three geochemical groups are represented in the tephra stratigraphy, defined by relative proportions of SiO2, TiO2, Sr, Cr, and Ni, and determined by SAHN Clustering analysis. These three groups are defined in the basal, middle, and upper portions of the stratigraphy and generally correlate with the three major geochemical groups defined in the SMVF lava flows. Correlation between the tephra and …


Aestheticization As A Type Of Erasure: An Ecocritical Examination Of Three Etchings From James Mcneill Whistler's 'Thames Set' (1859-1871), Sydney Ion May 2023

Aestheticization As A Type Of Erasure: An Ecocritical Examination Of Three Etchings From James Mcneill Whistler's 'Thames Set' (1859-1871), Sydney Ion

Theses and Dissertations

This thesis explores “A Series of Sixteen Etchings of Scenes on the Thames” (1859-1871), Thames Set, by James Abbott McNeill Whistler (1834-1903), a group of etchings that negotiates the effects of the “Great Stink” on the Thames riverbank and its people. I argue that the series exhibits a strange paradox: the intentional exclusion of accurate environmental elements and sensorial details to achieve a romanticized nostalgic framework that serves Whistler’s aesthetic ideals. This aestheticization of the environmental crisis is the foundation from which Whistler’s modernization grew. Recent research has understood the Thames Set as evidence of Whistler’s involvement in depicting lower-class …


Comparative Study Of Variable Selection Methods For Genetic Data, Anna-Lena Kubillus May 2023

Comparative Study Of Variable Selection Methods For Genetic Data, Anna-Lena Kubillus

Theses and Dissertations

Association studies for genetic data are essential to understand the genetic basis of complex traits. However, analyzing such high-dimensional data needs suitable feature selection methods. For this reason, we compare three methods, Lasso Regression, Bayesian Lasso Regression, and Ridge Regression combined with significance tests, to identify the most effective method for modeling quantitative trait expression in genetic data. All methods are applied to both simulated and real genetic data and evaluated in terms of various measures of model performance, such as the mean absolute error, the mean squared error, the Akaike information criterion, and the Bayesian information criterion. The results …


Long-Term Spatial And Temporal Assessment Of Criteria Air Pollutants Concentration Trends In The Lower Rio Grande Valley Region Of Texas, Usa, Md Salahuddin Majumder May 2023

Long-Term Spatial And Temporal Assessment Of Criteria Air Pollutants Concentration Trends In The Lower Rio Grande Valley Region Of Texas, Usa, Md Salahuddin Majumder

Theses and Dissertations

Air pollution is a substantial environmental challenge all over the world. This study investigated the long-term air pollution levels in the Lower Rio Grande Valley region, by utilizing data collected from five continuous ambient monitoring stations in two counties over 23 years, from January 2000 to December 2022, to analyze daily, monthly, and seasonal variations of different pollutants, including ground-level ozone, particulate matter, and carbon monoxide. This study also identified distinct daily and seasonal patterns for O3, PM2.5, PM10, and CO at each monitoring site, influenced by factors such as traffic emissions, temperature, solar radiation, indoor heating, and weather conditions. …


Cellulose Nanocrystal Dielectric Elastomers, David Frailey May 2023

Cellulose Nanocrystal Dielectric Elastomers, David Frailey

Theses and Dissertations

Optical devices, such as filters and sensors, have numerous advantages including compactness in size and immunity from electromagnetic interference. The fabrication of optical devices often requires precision and complicated processing, resulting in expensive and delicate components. Cellulose nanocrystals (CNCs) are biomaterials that can self-assemble into liquid crystals, similar to those used in electronic displays. This material can function as an optical grating by reflecting/transmitting circularly polarized light at certain wavelengths and viewing angles. Since gratings are building blocks of optical systems, like lasers and lidars, their fabrication at low costs will enable the further proliferation of optical technologies. Furthermore, if …


Extracting Patterns Of Semantic Roles From Accident Narratives, Soundarya Jayakumar May 2023

Extracting Patterns Of Semantic Roles From Accident Narratives, Soundarya Jayakumar

Theses and Dissertations

Accident databases are filled with rich information about accidents. Analyzing these datasets can reveal useful information which can be used to prevent similar accidents in the future. Policy makers, and safety management organizations can design appropriate measures based on the analysis done to prevent accidents. Besides structured data, crash reports include natural language narratives which contain valuable accident-related information which is otherwise not present in the structured data. Using natural language processing (NLP) techniques one can analyze these narratives and mine hidden patterns of accidents from them. The thesis focuses on developing an algorithm to extract common patterns of semantic …


The Search For The Four-Electron Reduced Intermediate In The Cytochrome C Nitrite Reductase (Ccnir) - Catalyzed Reduction Of Nitrite, Victoria Lynn Mandella May 2023

The Search For The Four-Electron Reduced Intermediate In The Cytochrome C Nitrite Reductase (Ccnir) - Catalyzed Reduction Of Nitrite, Victoria Lynn Mandella

Theses and Dissertations

Although there are many nitrogen species in the nitrogen cycle, nitrite occupies a centralrole. Nitrite can either reduce to ammonium or dinitrogen or oxidize to nitrate. Ammonium and nitrate can be found in the environment; however, problems arise when the accumulation of these nitrogen species leads to eutrophication in aquatic environments. High ammonium or nitrate levels in lakes or other bodies of water can lead to the overgrowth of algae, which causes the blockage of sunlight to different species below the water surface. Imbalance in the ecosystem is a serious environmental issue that can be addressed by further studying and …


Vision-Based Object Manipulation For Activities Of Daily Living (Adl) Assistance Using Assistive Robot, Md Tanzil Shahria May 2023

Vision-Based Object Manipulation For Activities Of Daily Living (Adl) Assistance Using Assistive Robot, Md Tanzil Shahria

Theses and Dissertations

Upper and lower extremity (ULE) functional deficiencies, which limit a person's ability to perform everyday tasks, have increased at an alarming rate over the past few decades. It is essential for individuals with impairments to take care of themselves without requiring a significant amount of support from other individuals. Few assistive devices are available in the market to make their life comfortable, yet controlling them sometimes becomes challenging for this group of people. Robotic devices are emerging as assistive devices to assist individuals with limited ULE functionalities in activities of daily living (ADL). As most of these devices only allow …


Estimating Energy Cost Of Physical Activities From Video Using 3d-Cnn Networks, Pragya Shrestha Chansi May 2023

Estimating Energy Cost Of Physical Activities From Video Using 3d-Cnn Networks, Pragya Shrestha Chansi

Theses and Dissertations

This research proposes a machine learning model that can estimate the energy cost of physical activities from video input. Currently, wearable sensors are commonly used for this purpose, but they have limitations in terms of practicality and accuracy. A deep learning model using three dimensional convolutional neural network (3D-CNN) architecture was used to process the video data and predict the energy cost in terms of metabolic equivalents (METs). The proposed model was evaluated on a dataset of physical activity videos and achieved an average accuracy of 71% on energy category prediction task and an root mean squared error (RMSE) of …


Numerical Simulations Of Tidal Disruption Events, Alexandra Elise Spaulding May 2023

Numerical Simulations Of Tidal Disruption Events, Alexandra Elise Spaulding

Theses and Dissertations

The detection of supermassive black holes (SMBH) in our universe has proven to be a challenge. One way to find an SMBH in a quiescent, inactive galaxy is through a tidal disruption event, or a TDE. A TDE occurs when a star is slightly perturbed and is subsequently disrupted by the SMBH. When this happens, part of the debris from the disrupted star remains bound to the SMBH while the rest is unbound. The SMBH accretes the bound matter and reveals their presence by a temporary X-ray flare, lasting a few months. Using conservation of energy, the fallback rate of …


Leveraging Biomedical Ontological Knowledge To Improve Clinical Term Embeddings, Fuad Hatem Abuzahra May 2023

Leveraging Biomedical Ontological Knowledge To Improve Clinical Term Embeddings, Fuad Hatem Abuzahra

Theses and Dissertations

ABSTRACT Leveraging Biomedical Ontological Knowledge to Improve Clinical Term Embeddings by Fuad Abu Zahra The University of Wisconsin-Milwaukee, 2023 Under the Supervision of Dr. Rohit J. Kate This research is on obtaining and using word embeddings for natural language processing tasks in the biomedical domain. Word embeddings are vector representations of words commonly obtained from large text corpora. This research leverages the biomedical ontology of SNOMED CT as an alternate source for obtaining embeddings for clinical terms. The existing graph-based methods can only give embeddings for concepts (i.e., nodes of the graph) of an ontology, hence we developed a novel …