Physical Sciences and Mathematics Commons^™

Modulatory Effects Of Deacetylated Sialic Acids (A Sugar Residue) In Nk-Mediated Cytotoxicity And Targeted Therapy By Receptor Tyrosine Kinase Inhibitors, Mathias Tawiah Anim

Electronic Theses and Dissertations

The complex nature of the biology of cancer is still an unraveling science, yielding several biomarkers that have served as molecular targets for detection and treatment of the disease. How sugars, glycans, play a role has remained relatively uninvestigated. Sialic acid (Sia), a sugar residue on the surface of cells, has been identified as a hallmark of cancer and its progression. Sialic acid can be highly functionalized, but we became interested in acetylated Sias. This functional group is modulated by Sialate O- acetylesterase (encoded by the gene SIAE) and Sialate O-acetyltransferase (encoded by CASD1), enzymes that play a crucial role …

Development And Assessment Of Gamified Process-Oriented Guided Inquiry Learning Activities In Undergraduate Large Lecture Chemistry Courses, Nathan Turner

Electronic Theses and Dissertations

Students who take general chemistry and do not perform well are more likely to pursue an alternative degree or remove themselves from STEM curriculum entirely. Poor academic performance and high student attrition rates in general chemistry courses have resulted in the perception of chemistry courses being gatekeepers for students in pursuit of STEM degrees. Process-Oriented Guided Inquiry Learning (POGIL) has shown promising results in both lecture and laboratory teaching on student performance in chemistry while gamification has been used to enhance student learning experiences to help students grasp chemistry concepts. The current project blends two student-centered approaches, gamification and POGIL, …

A Class Of Regression Models For Pairwise Comparisons Of Forensic Handwriting Comparison Systems, Cami M. Fuglsby

Electronic Theses and Dissertations

Handwriting analysis is a complex field largely living in forensic science and the legal realm. One task of a forensic document examiner (FDE) may be to determine the writer(s) of handwritten documents. Automated identification systems (AIS) were built to aid FDEs in their examinations. Part of the uses of these AIS (such as FISH[5] [7],WANDA [6], CEDAR-FOX [17], and FLASHID®2) are tomeasure features about a handwriting sample and to provide the user with a numeric value of the evidence. These systems use their own algorithms and definitions of features to quantify the writing and can be considered a black-box. The …

Impacts Of Land Cover Change On Urban Heat Island (Uhi) In Denver From 1985 To 2020, Sadia Islam Ritu

Electronic Theses and Dissertations

Rapid urbanization due to land use and land cover change has become one of the major problems in the fastest-growing cities during the past few decades. Land surface temperature has changed dramatically due to urban expansion, and it is a major driver of urban eco-environmental change. Increasing temperature leads to the Urban Heat Island (UHI) problem in rapidly growing cities like Denver, contributing to global warming at multiple scales. UHI study is significant to monitor and mitigate the urban heat islandrelated problem in the study area Denver. Satellite remote sensing analysis ready data (ARD) with 30 m resolution based on …

Addressing Soil Carbon Sequestration Response From Multispecies Dairy Forage Systems And Modeling Rangeland Beef Cow Dry Matter Intake Using Precision Enteric Emissions Measurements, Lillian J. Mcfadden

Electronic Theses and Dissertations

Regenerative agriculture is a pressing matter for the dairy industry to address cropland sustainability and carbon sequestration. One regenerative management practice that has been identified to help with row crop sustainability for key metrics like soil organic carbon (SOC) is complex covers. When producers use complex covers one of the main challenges is that it takes time to detect a change in SOC. However, simulation models are a tool that can be used to help determine if a regenerative practice is a strategy that gives the best results (i.e., increased SOC) while aligning with long-term production goals. Therefore, our objectives …

Comprehensive Analysis And Forensic Investigation Of Cyanide, Thiocyanate, And 2-Amino-2-Thiazoline-4-Carboxylic Acid In-Ante- And Postmortem Blood Utilizing Advanced Analytical Techniques, Abdullah Hamad Alluhayb

Electronic Theses and Dissertations

Cyanide (CN), present as cyanide anion (CN-) or hydrogen cyanide (HCN), is a deadly poison. The main mechanism of CN toxicity is blocking terminal electron transfer, leading to cellular hypoxia, cytotoxic anoxia, and potential death. Determining blood CN concen-trations along with its major metabolite, thiocyanate (SCN-), is crucial. A sensitive method for concurrent detection of CN and SCN- from human ante- and post-mortem blood via liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) analysis was devel-oped. The method involved active microdiffusion with chemical modification using naph-thalene-2,3-dicarboxaldehyde (NDA) and taurine, while monobromobimane (MBB) mod-ification was used for SCN-. The method showed good sensitivity for …

Understanding The Role Of Hba/Hbd Variations On Deep Eutectic Solvent Properties And Activity Using Acetylsalicylic Acid As A Model Drug, Michael Frimpong

Electronic Theses and Dissertations

Deep eutectic solvents (DES) are emerging as a versatile class of solvents, attracting considerable attention for their unique solvent properties and potential applications. This study examines the effects of variations in combinations as well as molar ratios of hydrogen-bond acceptor (HBA) and hydrogen-bond donor (HBD) on the structure of DES. It further explores the structure-activity relationship, measured using the rate of acetylsalicylic acid (ASA) degradation in the solvent. The project is based on the model that variations in HBA/HBD combinations and their relative molar ratios impact the solvent structure (hydrogen bonding), observable in physicochemical measurements, infrared (IR), and nuclear magnetic …

Effects Of Agricultural Chemicals On Native Plants Of The Northern Great Plains, Gabrielle Bolwerk

Electronic Theses and Dissertations

Agricultural chemicals are ubiquitous on the Northern Great Plains landscape and have negative impacts on non-target plant communities, even at small doses. Northern Great Plains grassland plant communities may experience herbicide drift from agricultural fields or be subject to livestock pharmaceuticals in grazing lands. My research objective was to evaluate if and how native plants are affected by agricultural chemical presence at different concentrations. In Chapter 2, I studied the effect of different concentrations of three common agricultural herbicides (2,4-D, atrazine, and trifluralin) on the germination, emergence, and growth of native plant species of the Northern Great Plains. I performed …

Comparative Analysis Of Membership Inference Attacks In Federated Learning, Saroj Dayal

Electronic Theses and Dissertations

Given a federated learning model and a record, a membership inference attack can determine whether this record is part of the model’s training dataset. Federated learning is a machine learning technique that enables different parties to train a model without the need to centralize or share their local data. Membership inference attack risks the private datasets if those datasets are used to train the federated learning model and access to the generated model is available. There is a need to study the membership inference attack in the federated learning setting. In this thesis, we empirically investigated and compared various membership …

Biophysical Insights Into Peptide And Alcohol Perturbations On Biomimetic Membranes, Michael Hai Nguen

Electronic Theses and Dissertations

Biological membranes exist in every domain of life. Life exists due to the presence of these special structures for which we take for granted. They are composed of fatty lipids and workhorse proteins and act as the premier interface of biological processes. Due to the sheer quantity and complexity within their thin boundary, studying their actions and properties pose challenges to researchers. As a result, simplified biomembrane mimics are employed regularly. We will use several types of biomembrane mimics to understand fundamental properties of membranes. In the present thesis, we also attempt to move beyond the canonical structure-based theories upon …

Enzymatic Removal Of Diclofenac And Aceclofenac From Synthetic Wastewater By Soybean Peroxidase, Sarah Pishyar

Electronic Theses and Dissertations

Pharmaceutical medications that are a class of emerging contaminants have been detected in wastewater treatment facilities' influent and effluent, and they have reached water sources in amounts ranging from ng/L to ug/L. They threaten the environment and non-target life. Soybean peroxidase (SBP)-catalyzed process was studied to remove two non-steroidal anti-inflammatory drugs (NSAIDS) diclofenac and aceclofenac through enzymatic oxidation from synthetic wastewater. SBP can be extracted from soybean hulls, a by-product of the soybean industry. First, the experiments studied the viability of SBP-catalyzed removal on these two compounds, then the operational parameters including pH, the molar ratio between hydrogen peroxide and …

Functional Characterization Of Hodi, A Dead-Box Rna Helicase In Toxoplasma Gondii, Using Rna-Protein Tethering Assay, Ronaldo Eid

Electronic Theses and Dissertations

Toxoplasma gondii, an obligate intracellular apicomplexan parasite, is the causative agent of toxoplasmosis which has serious complications in immunocompromised individuals and in offspring of infected mothers. Central to the parasite’s pathogenesis and transmission is its adaptation to various forms of cellular stress. A conserved stress response by Toxoplasma gondii is translational control induced by phosphorylation of TgIF2α, during which non-translating mRNAs accumulate in messenger ribonucleoprotein (mRNP) granules that disassemble upon stress relief. DEAD-box RNA helicases are candidates involved in the regulation of mRNP granules and also function in translational control. In this study, it was shown that the flanking …

Assessment Of Water Quality Index, Light Attenuation, And Nutrient Sequestering By Submerged Aquatic Vegetation In The Detroit River, John Scannell

Electronic Theses and Dissertations

This thesis assessed water quality – submerged aquatic vegetation interactions in the Detroit River. Submerged aquatic vegetation provides essential ecosystem services that support aquatic biodiversity and regulating ecosystem services such as carbon sinks, purifying water and nutrient cycling. Chapter 2 explored how degraded water quality in the Detroit River limits submerged aquatic vegetation via light limitation. A water quality index and light extinction coefficients were measured at 21 sites along with installation of in-situ water quality sondes at 4 sites to measure water quality at high temporal resolution. The river wide median euphotic depth was estimated to be 1.30 m, …

Webcam-Based Optical Mark Reader For Grading Assessments, Muhammad Fahad Zafar

Electronic Theses and Dissertations

Optical Mark Recognition (OMR) is a process of retrieving information from the forms where users put marks in particular locations. OMR technique has been improved significantly since its inception, moving from specialized hardware-based solutions to more adaptable and sophisticated software-based solutions using a scanner. Recently, webcam-based software solutions have emerged because of their affordability and ease of use. In this thesis, we propose an improved webcam-based OMR solution for grading the student tests given on a specifically formatted answer sheet. We apply various image processing techniques to achieve effective grading, resolving technical problems stemming from multiple factors like image orientation, …

Sediment Microbial Community Diversity And Function In Response To Legacy And Prevailing Pollutants In Southern Ontario Watersheds, Nicolas Falk

Electronic Theses and Dissertations

Managing and mitigating point and non-point contamination to freshwater resources depends on reliable and sensitive monitoring of ecosystem health. Microorganisms in surface waters and sediments respond rapidly to anthropogenic disturbances, making them valuable bioindicators of human-induced landscape change. However, there lacks a baseline understanding of microbial community composition and function in industrially and agriculturally impacted regions of the Great Lakes. Without a reference state of microbial diversity and activity, future investigations seeking to integrate microorganisms into ecosystem assessments will lack context. Using genomic tools and measurements of chemical and nutrient contaminants, this thesis provides case studies of microbial community responses …

Consequences Of Environmental Manipulation On Behavioural And Neuromorphological Plasticity As It Relates To The Reintroduction Of Atlantic Salmon (Salmo Salar) To Lake Ontario, Ali I. Mokdad

Electronic Theses and Dissertations

The reintroduction of imperilled species has become an important tool in conservation biology and relies on the captive-rearing of remaining individuals, or a subset thereof, as a lifeline to prevent extinction. The success of reintroduction efforts has generally been low, mainly due to poor post-release performance of captive-reared animals. Captive-breeding programs tend to produce behaviourally and neurologically compromised animals that deviate from wild phenotypes and are less fit in natural settings. While genetic adaptation can account for some of the behavioural deficiencies expressed by captive-reared animals, phenotypic plasticity has been shown to play a large role. Phenotypic plasticity is generally …

Reducing Model Memorization To Mitigate Membership Inference Attacks, Sheikhjaberi

Electronic Theses and Dissertations

Given a machine learning model and a record, membership inference attacks determine whether this record was used as part of the model’s training dataset. This can raise privacy issues.

There is a desideratum to providing robust mitigation techniques against this attack that will not affect utility. One of the state-of-the-art frameworks in this area is SELENA, which has two phases: Split-AI and Distillation to train a protected model, which by giving non-members behavior to members tries to mitigate membership inference attacks.

In this thesis, we introduce a novel approach to the Split-AI phase, which tries to weaken the membership inference …

Multi-Data Source Recommendations With Derived Sequential Pattern Mining, Burhan Uddin

Electronic Theses and Dissertations

Existing multi-source RS algorithms, such as ECCF19, use item categories to extend the CF model and enhance the preference matrix. The CD-SPM19 model uses item ontology to derive semantic similarity information to enrich the collaborative filtering (CF) step. The HPCRec18 model derives a consequential bond between click to purchase to predict preferences for users with no purchase history. Finally, the HSPRec19 model using the historical sequential purchase database (SHOD) algorithm, derives sequential purchase patterns from historical purchase data. It then uses the consequential bond in mined patterns to improve the user-item matrix for CF. None of these systems use historical …

Debertnext: A Multimodal Fake News Detection Framework, Kamonashish Saha

Electronic Theses and Dissertations

There is a rapid influx of fake news nowadays, which poses an immense threat to our society. Fake news has been impacting us in several ways which include changing our thoughts, manipulating opinions, and also causing chaos due to misinformation. With the ease of access and sharing information on social media platforms, such fake news or misinformation has been spreading in different modalities which include text, image, audio, and video. Although there have been a lot of approaches to detecting fake news in textual format only, however, multimodal approaches are less frequent as it is difficult to fully use the …

Learning Networks With Attention Layers For Team Recommendation, Sagar Kaw

Electronic Theses and Dissertations

The Team Formation Problem aims to identify a group of experts who possess the required skills to complete a common goal. Graph-based approaches have been commonly used to solve this problem, but recently, researchers have started exploring this problem from the perspective of social information retrieval and applying neural architectures to recommend teams of experts. However, the learning process of these architectures is faced with several challenges. This includes the inability to handle network modifications after the training process is over as well as the time complexity of the learning process is high, which is proportional to the size of …

Dynamic Distributed Energy Resources For Expansion Of Ontario’S Greenhouse Sector, Lysandra Naom

Electronic Theses and Dissertations

The vegetable greenhouse sector is rapidly growing and adopting technology advances like supplemental lighting. Supplemental lighting has a dynamic impact on the demand and consumption of a greenhouse’s electricity load. There is uncertainty on the rate of adaptation of technologies and the impact this could have on the power consumption of the sector. Without electricity availability, the sectors innovation and expansion can come to a halt. This research focused on investigating greenhouse electrical load models and lighting trends to forecast demand on electricity grids and discover potential for Distributed Energy Resource (DER) applications.

This thesis presents a series of studies …

Constructing Adversarial Examples In Question-Answering Systems, Vishakha Gautam

Electronic Theses and Dissertations

Being an NLP pre-training model built with transformer and attention mechanism, BERT has proven to be highly efficient in developing various applications like text classification, machine translation, question-answering systems etc. Despite the recent advancement, however, the generalizability of the models remains a challenging issue. In this thesis, we study the generalizability issues of the prediction models in the question-answering systems, particularly for the unanswerable examples. To gain the insight about where the models do not generalize well, we are interested in constructing adversarial examples that are challenging for the model to predict correctly. The adversarial examples are obtained by pairing …

Hydrologic Modeling With Remote Sensing For The Estimation Of Groundwater Resources Within The Sand River Catchment, South Africa, Sophia Bakar

Electronic Theses and Dissertations

The Sand River Catchment is an important tributary of the transboundary Limpopo River in South Africa, which spans Botswana, Mozambique, South Africa, and Mozambique. Groundwater is a critical resource in the region, especially in the context of population growth and climate change. Data are needed for proper management of these water resources. In regions where groundwater data are sparse in time, space, or both, the most promising solutions come from satellites and hydrologic models. Regional literature suggests that the Soutpansberg Mountains, located within the Sand Catchment, are high-elevation water towers with uncertain groundwater resources. Improved understanding of groundwater resources in …

Assessments Of Water Chemistry And Fish Community Structure In The Buffalo Creek Watershed, Tributary To The Allegheny River In Armstrong And Butler Counties, Pennsylvania, Kathleen Wilson

Electronic Theses and Dissertations

The Buffalo Creek watershed has experienced water quality impairments for various reasons, including but not limited to, agricultural influence, abandoned mine drainage (AMD), on-site wastewater malfunction, and stormwater. The source and cause of the most prevalent impaired areas remains unknown. The goal of this study was to analyze water chemistry using state water quality standards and mass ratio analysis, then to conduct fish community analysis. We found toxic metal pollution across the watershed, with iron, cadmium, copper, and selenium frequently exceeding criteria. We determined which streams are polluted by resource extraction activities by conducting mass ratio analysis. We found conventional …

Gold (I) Tetrathiomolybdate Clusters: Synthesis, Characterization, Computational Studies, And Reactivity With Thiophenol And Selenophenol, Dhirgam Humaidy

Electronic Theses and Dissertations

This thesis describes the synthesis and reactivity of heterometallic complexes containing medicinally active Au(I) and tetrathiomolybdate, [MoS₄]^2-. The research is motivated by the idea of multifunctional drugs, which are designed to treat diseases through two or more mechanisms of action. Five clusters of the general form, [MoS₄(AuL)₂] were prepared: C-1 (L=IPr), C-2 (L=IBzMe), C-3 (L=IMes), C-4 (L=PPh₃), and C-5 (L=PEt₃). The clusters with NHC ligands, C-1, C-2, and C-3 were prepared for the first time and thoroughly characterized by ¹H NMR,¹³C{¹H} …

Understanding The Impacts Of Anthropogenic Effects An Habitat Variability Interactions On Maine's Rocky Intertidal Ecosystem, Laura Braun

Electronic Theses and Dissertations

The rocky intertidal ecosystem is an important ecological and cultural aspect of the picturesque Maine coast, playing a vital role in not only Maine’s coastal ecosystem, but also to Maine’s economy. It’s distinct community structure along the sharp elevational gradient and the presence of daily stressors (wave action, heat, and desiccation), make the rocky intertidal ecosystem an important model ecosystem to monitor for effects from anthropogenic impacts. In this thesis, I describe attempts to monitor and understand the impacts of two of these anthropogenic impacts on this system: climate change and industrial harvesting of Ascophyllum nodosum along Maine’s coast. For …

Speciated Isotope Dilution Mass Spectrometry In Combination With Thor’S Hammer Metaspike Technology For The Assessment Of Low-Level Biomarkers For Human Health Evaluation, Ashley Ebert

Electronic Theses and Dissertations

Our research team has been focused on quantifying important biological analytes in human blood samples to delineate the biochemical processes underlying certain states of dysfunction and evaluate treatment efficacy. These efforts have been guided by laboratory measurements with the input of medical experts. Speciated isotope dilution mass spectrometry (SIDMS) explained in detail in EPA Method 6800 has been successfully applied in the quantification of an important biomarker analyte for immune function and detoxification processes: glutathione. Past research has proven the molecule a biomarker for autism spectrum disorder (ASD) in the form of the reduced/oxidized glutathione (GSH/GSSG) ratio, and literature has …

Quantum Computations And Molecular Dynamics Simulations: From The Fundamentals Of Antimicrobial Resistance To Neurological Diseases, Angel Tamez

Electronic Theses and Dissertations

Biophysical phenomena are modeled using a combination of quantum and classical methods to interpret and supplement three distinct and diverse problems in this dissertation. In the first project, decarboxylation reactions are ubiquitous across chemical and biological disciplines, yet the origin of non-catalytic solvent effects remains elusive. Specific solvent structure and energetics have not been well described for the monoanion of malonate, nor corrected from the gas-phase charge-assisted intramolecular hydrogen bond model known as “pseudochair”. In the aqueous phase, a low-lying energy conformer known as the “orthogonal conformation” is computed to be preferred by a three-water cluster of hydrogen bonding over …

First-Row Transition Element Distribution Across The Blueschist-Eclogite Transition: A Case Study From New Caledonia, Natalie M. Harmon

Electronic Theses and Dissertations

The first-row transition elements (FRTE), namely Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn, are potential redox tracers in the solid Earth due to their general compatibility during crustal processes, and the redox-sensitive nature of certain elements. Despite widespread interest in the FRTEs, their distribution and behavior in subduction zones, particularly across the blueschist-eclogite transition, are still poorly constrained. New Caledonia preserves a prograde subduction zone with largely coherent continuous progression in metamorphic grade. Although the metamorphic sequence has been disrupted to some extent, this is the closest natural example of blueschist and eclogite that was sourced …

Carbon Dioxide Emissions From Deadwood In Forests Of The Northeastern United States, Zoe Read

Electronic Theses and Dissertations

As the climate changes, understanding the sources and sinks of greenhouse gases such as carbon dioxide (CO₂) is increasingly important. However, several components of the carbon cycle within forests remain poorly understood. For example, knowledge gaps exist in our understanding of CO₂ emissions from coarse woody material (CWM; logs and stumps), including how emissions change over time, how they are influenced by environmental variables, and how they compare to soil and ecosystem-level CO₂ emissions.

To fill these knowledge gaps, we examined CO₂ emissions from CWM at three sites. We sampled 18 red spruce (Picea …