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Photoelectic Driven Decomposition Of Uracil Via Hard X-Ray Irradiation, Trimaan Malik

UNLV Theses, Dissertations, Professional Papers, and Capstones

Radiation damage into biological samples creates substantial challenges across a wide range of fields, from biochemistry to materials science. This comprehensive study investigates the effects of x-ray irradiation on uracil, the only nucleobase exclusive to Ribonucleic acid (RNA), to understand how doping with 10% (by mass) of specific powdered elements impacts the sustained radiation damage. The experiments were conducted at the Brockhouse Undulator Beamline of the Canadian Light Source synchrotron. Virgin and doped uracil samples were irradiated with hard x-rays, above their respective absorption edges, and studied with x-ray diffraction to compare their decomposition behaviors. The Uracil reflections on the …

Chm116 Principles Of Chemistry Ii Lecture Slides, Leah S. Cohen, Probal Banerjee

Open Educational Resources

This file contains the lecture slides that are used in CHM116, Principles of Chemistry II.

Synthesis And Characterization Of Indole-Based Zinc Dipyrrin Photosensitizers, Jean-Pierre Sanza

Electronic Theses and Dissertations

Metal complexes of dipyrromethene (dipyrrins) used as sensitizers in photocatalysis offer a way to harness solar energy in chemical bonds to create new fuels. This offers the dual role of reducing fossil fuel dependence and atmospheric CO₂ levels. Traditionally, metal dipyrrin complexes are synthesized using substituted pyrroles, aldehydes, and transition metals. Indoles have a more expanded pi-electron system and their dipyrrin-type complex may exhibit visible light absorption, suggesting that they can act as photosensitizers for CO₂ reduction processes. A novel indoledipyrromethene was synthesized using unsubstituted indole and mesitaldehyde. The complex exhibits visible light absorption at 422 nm. Its …

Bacteria Synergized With Pd-1 Blockade Enhance Positive Feedback Loop Of Cancer Cells-M1 Macrophages-T Cells In Glioma, Qi Chen, Yuyi Zheng, Xiaojie Chen, Yuan Xing, Jiajie Zhang, Xinyi Yan, Qi Zhang, Di Wu, Zhong Chen

Faculty, Staff and Student Publications

Cancer immunotherapy is an attractive strategy because it stimulates immune cells to target malignant cells by regulating the intrinsic activity of the immune system. However, due to lacking many immunologic markers, it remains difficult to treat glioma, a representative "cold" tumor. Herein, to wake the "hot" tumor immunity of glioma, Porphyromonas gingivalis (Pg) is customized with a coating to create an immunogenic tumor microenvironment and further prove the effect in combination with the immune checkpoint agent anti-PD-1, exhibiting elevated therapeutic efficacy. This is accomplished not by enhancing the delivery of PD-1 blockade to enhance the effect of immunotherapy, but by …

A Conceptual Understanding Of Concepts In Organic Chemistry, Timerra Chisham

Theses/Capstones/Creative Projects

As students continue to make the transfer into organic chemistry from general chemistry, they will have to adjust to the new type of thinking required so that they will not fall behind in understanding material and will have success in the course. For this research project, I explored which concepts taught in organic chemistry are the most difficult for students to grasp. I had two main goals for this project. The first one is the central idea that I focused on, which was to see which concepts that have been taught in Organic Chemistry 1 the students are most confident …

Selectivity Studies Of Cbds Against Cb1 And Cb2 Using Docking Approach, Brandon Villanueva Sanchez, Andy Zhong

Theses/Capstones/Creative Projects

Cannabis sativa is an herbal plant that is used for recreational and medicinal purposes. The two main components, ∆9-Tetrahydrocannabinol (THC) and Cannabidiol (CBD), are responsible for the two different uses. Both compounds have been heavily researched, with their mechanisms of action, docking site, and binding affinity and efficacy identified. Researchers have synthesized various analogs by altering the carbon side chains of THC/CBD’s molecular structures. These synthetic analogs have been created to study the structure-function relationship of different molecules to the endocannabinoid system receptors, CB1 and CB2. Here, we conduct a docking study of various THC/CBD analogs to both receptors using …

Brain-Inspired Continual Learning: Rethinking The Role Of Features In The Stability-Plasticity Dilemma, Hikmat Khan

Theses and Dissertations

Continual learning (CL) enables deep learning models to learn new tasks sequentially while preserving performance on previously learned tasks, akin to the human's ability to accumulate knowledge over time. However, existing approaches to CL face the challenge of catastrophic forgetting, which occurs when a model's performance on previously learned tasks declines after learning the new task. In this dissertation, we focus on the crucial role of input data features in determining the robustness of CL models to mitigate catastrophic forgetting. We propose a framework to create CL-robustified versions of standard datasets using a pre-trained Oracle CL model. Our experiments show …

Examining The Relationship Between Manning's Roughness Coefficient And Stage, Henry Holtkamp

Biological and Agricultural Engineering Undergraduate Honors Theses

This paper uses LOESS regression to predict Manning's roughness coefficient to calculate flows in natural stream channels. Manning's roughness coefficient can introduce variability into Manning's equation, potentially destabilizing results. Utilizing LOESS to find n based on backcalculated n from collected discharge vs. stage information is the best way to acquire accurate Manning's roughness coefficient values at a variety of flows. Book values tend to drastically overestimate which can have wide-ranging implications for water allocation, flood management, maintaining environmental flows, and maintaining water quality.

Chemical Analysis Of Hemp-Infused Supplements Using High Performance Liquid Chromatography And Gas Chromatography-Mass Spectrometry, Julie A. Milbrand

Forensic Science Master's Projects

Hemp and marijuana consumption in the United States can be dated back many centuries as being an essential component of the medicinal, industrial, and recreational markets while maintaining its extremely controversial status amongst the scientific and political communities. While researchers suggest that the plant in which both hemp and marijuana are derived from, Cannabis Satvia, contains more than 600 chemicals, the vast majority of research has been conducted on cannabinoids, which account for about 60 of them. Major phytochemicals from cannabis include its psychoactive agent, tetrahydrocannabinol (THC), and non-psychoactive cannabidiol (CBD), cannabigerol (CBG), and many others. Employing the use …

Synthesis And Structure Of Curaxin Analogs, Elizabeth E. Brown

Forensic Science Master's Projects

Curaxins are small molecules that have demonstrated anti-cancer activity through the activation of p53 and inhibition of nuclear factor-kB. Curaxins interfere with DNA-histone interactions, impeding DNA repair and inducing chromatin destabilization. This leads to apoptosis through alterations in spatial genome organization and oncogene expression. The results are due to DNA binding activity. A team of researchers, including a Roswell Park Cancer Institute group, discovered these molecules. This project aims to synthesize a diverse library of novel analogs of curaxin through a modified literature protocol to enhance the chemotherapeutic potency while minimizing non-specific cytotoxicity. N-alkylation of diacetyl carbazole followed by saponification …

Design, Synthesis, And Optimization Of Allosteric Inhibitors Of Hiv-1 Integrase, Krunal H. Patel

Dissertations

The human immunodeficiency virus type 1 (HIV-1) infection remains a global health crisis, necessitating the development of innovative antiviral strategies. During the integration step, HIV-1 integrase (IN) interacts with viral DNA and the cellular cofactor LEDGF/p75 to effectively integrate the reverse transcript into the host chromatin. Recently, a novel class of antiretroviral agents called Allosteric Inhibitors of HIV-1 Integrase (ALLINI) compounds has emerged as a promising avenue in the fight against HIV-1. While originally designed to inhibit IN-LEDGF/p75 interactions, these compounds have been shown to also impact late-stage viral maturation severely through IN multimerization. Induction of IN multimerization interferes with …

Evaluating Novel Approaches For Improving Anadromous Fish Passage In Coastal Rivers, Aaron Bunch

All Dissertations

Few of the world's rivers remain free-flowing for over 1000 km, significantly impacting anadromous fish populations due to dam-induced habitat fragmentation. Three partial migration barriers (low-head dams) on North Carolina's Cape Fear River (USA)—lock and dam 1 (LD1), lock and dam 2 (LD2), and lock and dam 3 (LD3)—impact American shad Alosa sapidissima, Atlantic sturgeon Acipenser oxyrinchus oxyrinchus, and striped bass Morone saxatilis populations. Mitigation strategies to pass fish upstream have included conservation locking, nature-like fishway construction, and environmental flows (e-flows). This study introduced a novel e-flow (dam submergence flow), tested acoustic double-tagging techniques for tracking American …

Patterns In Macrofaunal Abundance And Biodiversity At Sites In The Florida Keys, Cydney Wolff

Theses, Dissertations and Culminating Projects

Coral reef health in the Florida Keys, USA has been declining in recent years. To gain an understanding of the current state of macrofaunal abundance and biodiversity on these reefs, research was conducted to identify and count the macrofauna colonizing standardized settlement plates at two coral reef sites, one in the middle (Delta Shoal) and one in the lower (Pelican Shoal) Florida Keys. Plates were deployed for a one-month period in June 2023. At each site, the plates were placed at two heights: ocean bottom and 2 m above ocean bottom (two plates per height per site for a total …

Choreographing The Rhythms Of Observation: Dynamics For Ranged Observer Bipartite-Unipartite Spatiotemporal (Robust) Networks, Edward A. Holmberg Iv

LSU New Orleans Theses and Dissertations

Existing network analysis methods struggle to optimize observer placements in dynamic environments with limited visibility. This dissertation introduces the novel ROBUST (Ranged Observer Bipartite-Unipartite SpatioTemporal) framework, offering a significant advancement in modeling, analyzing, and optimizing observer networks within complex spatiotemporal domains. ROBUST leverages a unique bipartite-unipartite approach, distinguishing between observer and observable entities while incorporating spatial constraints and temporal dynamics.

This research extends spatiotemporal network theory by introducing novel graph-based measures, including myopic degree, spatial closeness centrality, and edge length proportion. These measures, coupled with advanced clustering techniques like Proximal Recurrence, provide insights into network structure, resilience, and the effectiveness …

Modification, Transport, And Sources Of Hydrocarbon Oxidation Products From Groundwater At Crude Oil And Diesel Spill Sites In Minnesota: Unveiling Common “Theems” Via Spectroscopy & Chromatography, Eduardo E. Turcios Valle

LSU New Orleans Theses and Dissertations

In this thesis, petroleum-contaminated groundwater from three spill-affected Minnesota sites—two contaminated with crude oil; one with diesel—is investigated to elucidate whether differences in degradation products from different parent oils exist. After spill events, parent molecules from the leaked oil seep underground and undergo microbial degradation over time, transforming into hydrocarbon oxidation products (HOPs), water-soluble contaminants that infiltrate groundwater aquifers, flowing into nearby environments and towns while exhibiting environmental persistence, toxicity to aquatic biota, and potential risks to humans that become exposed. Spectroscopic and chromatographic study of the structural themes and spatial distributions of HOPs reveals preferential degradation of aliphatic (biolabile) …

Introduction To Nuclear Magnetic Resonance Spectroscopy In A Geochemical Setting, Evan Mack

University Honors College

Nuclear magnetic resonance (NMR) spectroscopy is a powerful analytical tool that is heavily employed in organic chemistry, but lacks use in geochemistry. The technique is most useful for characterization and structural analysis of analytes, but also sees use in kinetics analysis, speciation, and detection. This work aims to answer these questions regarding NMR spectroscopy’s use in geochemical settings: Which nuclei are studied? For what purposes is each nucleus studied? What affects the scope of the technique and has caused it to not be widely used? How often is NMR spectroscopy used? What trends are there in the technique’s use? The …

College Of Natural Sciences Newsletter, Spring 2024, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

Page 1 Dean's Message
Page 2 New Faculty and New Club on Campus
Page 3 2024 URSCAD Awards
Page 4 Day of Scholars 2024
Page 5 SDSU's First Representation at the Association for Anatomy's 2024
Annual Conference
Page 6-7 2024 Honor's College Convocation
Page 8 Other Student Activities
Page 9 Faculty Awards
Page 10-11 Other News
Page 12 2024 Drone Day and American Association of Geographers Convention - Hawaii
Page 13 55th Annual Geography Convention
Page 14 2024 Stethoscope Ceremony
Page 15 Open PRAIRIE Data

Exploring The Potentials Of Delafossite-Coated Cotton Textiles: Photocatalytic Self-Cleaning, Uv-Blocking, Anti Microbial Activity And Hydrophobicity, Shahria Ahmed

Theses and Dissertations

Delafossite materials demonstrate multifunctional applications due to their excellent catalytic properties, which vary depending on their morphology, particle size, and synthetic method. Herein, a few novel applications of the delafossites are reported, which can be implemented in commercial, medical, and domestic settings. In present work we are presenting two different delafossite CuGaO2 and CuFeO2 nanoparticles and its composite with cotton fiber. Multifunctional cotton fabric is prepared by depositing a uniform coating layer of CuGaO2 and CuFeO2, exhibits excellent photocatalytic self-cleaning, UV blocking, and antimicrobial activity. CuGaO2 and CuFeO2 nanoparticle concentrations of 1mM and 2mM were deposited over the cotton fabric …

Catchment-Scale Thawing And Greening Decreases Long-Term Nitrogen Export In Ne Greenland, Shannon L. Speir, Jennifer L. Tank, Ada Pastor, Marc F. Muller, Mikhail Mastepanov, Tenna Riis

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Climate change is expected to alter nitrogen (N) export from Arctic rivers, with potential implications for fragile coastal ecosystems and fisheries. Yet, the directionality of change is poorly understood, as increased mobilization of N in a 'thawing' Arctic is countered by higher rates of vegetative uptake in a 'greening' Arctic, particularly in the understudied region of Greenland. We use an unprecedented dataset of long-term (n = 18 years) river chemistry, streamflow, and catchment-scale changes in snow and vegetation to document changing riverine N loss in Greenland. We documented decreasing inorganic and organic N loads, linked to decreasing snow stores, …

Ecological Dynamics Of Cenozoic North American Mammals, Alexandria Brandis Shupinski

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Understanding how community structure is affected by various ecological, climatic, and environmental changes is a long-standing goal in ecology. However, disentangling human impacts from these other variables is difficult when using short modern timescales and anthropogenically altered communities. The fossil record provides a means to investigate community structure dynamics across critical intervals, excluding humans as a variable. Here, in three studies, I assess changes in North American mammal paleocommunity structure across the last 66 million years (Ma) at multiple temporal and spatial scales. In Chapter 1, I identify changes in mammal functional diversity (FD) locally and continentally, using three independent …

Drag Reduction In Channel Flow Configurations For Laminar And Turbulent Flow Past Superhydrophobic Surfaces, Henry Louis Ems

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

In this work, we present friction drag reduction in minichannel laminar flow past superhydrophobic metallic surfaces. Femtosecond laser surface processing (FLSP), a one-step scalable method, was used to create permanent microscale and nanoscale structures on 316 stainless steel plates. The resulting superhydrophilic plates were covered by tall (215 μm) or short (27 μm) structures. The FLSP plates were then transitioned to superhydrophobic by evaporative deposition of a fluorinated silane, a low surface energy coating. Using purified water, the friction factor was obtained by measuring pressure drop along a minichannel with a rectangular cross section for flow rates corresponding …

Many Direct-To-Consumer Canine Genetic Tests Can Identify The Breed Of Purebred Dogs, Halie M. Rando, Kiley Graim, Greg Hampikian, Casey S. Greene

Computer Science: Faculty Publications

OBJECTIVE To compare pedigree documentation and genetic test results to evaluate whether user-provided photographs influence the breed ancestry predictions of direct-to-consumer (DTC) genetic tests for dogs.

ANIMALS 12 registered purebred pet dogs representing 12 different breeds. METHODS Each dog owner submitted 6 buccal swabs, 1 to each of 6 DTC genetic testing companies. Experimenters registered each sample per manufacturer instructions. For half of the dogs, the registration included a photograph of the DNA donor. For the other half of the dogs, photographs were swapped between dogs. DNA analysis and breed ancestry prediction were conducted by each company. The effect of …

Interpretation And Robustness Of Black-Box Ml Models For Secure Cyber Space, Qudrat E. Alahy Ratul

Boise State University Theses and Dissertations

The advent of sophisticated Machine Learning (ML) models has revolutionized the cybersecurity landscape, offering unprecedented capabilities to address complex challenges. Despite the ML model's capabilities, such models are still perceived as black boxes, the critical aspects of interpretability and robustness within these models often remain underexplored, rendering them susceptible to adversarial attacks and hindering their integration into sensitive applications. This dissertation focuses on interpretability and robustness of black-box ML models, aiming to fortify the cyberinfrastructure. Through a meticulous investigation of advanced techniques and methodologies, this work contributes towards elucidating and enhancing the interpretability and robustness of ML models in cybersecurity …

Survival Of Methanogens Desiccated On Mars Soil Simulants: Implications For Life On Mars, Lanee Knight

Biological Sciences Undergraduate Honors Theses

Because of Mars’s chemical features, it can be studied in the search for life and is a significant figure in the study of astrobiology (McKay, 2010). Dr. Kral’s laboratory studies methanogens, microorganisms in the domain Archaea, as possible life forms on Mars. Since some methanogens can withstand harsh environmental conditions and emit methane as a waste product, the growth of these microorganisms can be used as an indicator of potential life in the Mars subsurface (Kral et al., 1998). In this research, four methanogens, Methanothermobacter wolfeii, Methanobacterium formicicum, Methanosarcina barkeri, and Methanococcus maripaludi were desiccated in the …

Determination Of Common Drugs Of Abuse And Metabolites In Oral Fluid: Comparison Of Different Extraction Procedures, Melissa Koffer

Student Theses

Oral fluid has been gaining importance in forensic and clinical toxicology for many different drug testing scenarios. Oral fluid is composed of saliva, along with gingival fluid, bacteria, and food residues. Drug testing using oral fluid has many advantages over other matrices (blood, urine) such as the non-invasive collection, reduced risk of tampering, and shorter detection windows which show recent drug use. The purpose of this study was to develop an analytical method for the determination of 19 drugs of abuse and metabolites in oral fluid by liquid chromatography tandem mass spectrometry (LC-MS/MS) and compare three different extraction methods: liquid-liquid …

A Ui-Enhanced Approach To Generic Web-Based Scheduling, Tyler Hinrichs

Honors Scholar Theses

Administrative scheduling is a key aspect of a wide variety of systems, but despite being a widespread need, it is not a straightforward task. Organizational uniqueness introduces complexity when attempting to use algorithmic methods to automate scheduling, as individual organizations often have their own ways of determining various details and constraints of a schedule. However, in this paper, we assert that there are relevant commonalities that many different schedules fundamentally possess, allowing us to create a generic scheduling application that can be productively used for as many different scenarios as possible. After devising a schema that captures this generic representation, …

3d-Printed Microfluidic Devices For Electrochemiluminescence Detection Of Mirna, Oscar Clement

Honors Scholar Theses

This thesis outlines the research conducted over the past two years on the production and application of microfluidic devices (MFDs) in electrochemiluminescent-based bioanalytical assays. The work is categorized into two main projects: designing and manufacturing MFDs and developing electrochemiluminescent (ECL) assays for detecting Alzheimer's disease (AD) associated microRNAs (miRNAs) using CRISPR technology. The process of learning to design MFDs involved acquiring proficiency in computer-aided design (CAD) software, stereolithography (SLA) 3D printing, and iterative design techniques. The development of the ECL-based assay for AD miRNA was a multidisciplinary endeavor, combining elements of inorganic and biological chemistry. Although the research on the …

How Does Hummock Creation In Submerging Salt Marshes Alter Nitrous Oxide Fluxes?, Juliette Doyle

Honors Scholar Theses

Climate change is altering ecosystems and the services they provide. Salt marsh ecosystems typically protect coastal areas and filter nitrogen out of water, but are rapidly submerging due to rising sea levels and human development that prevents landward migration. Recent restoration efforts to preserve salt marshes attempt to build elevation capital and promote vegetation and animal habitat, but it is unclear how such efforts affect salt marsh biogeochemistry and dynamics of nitrous oxide, a potent greenhouse gas. To better understand how adding sediment to submerging salt marshes may alter nitrous oxide fluxes, I leveraged a salt marsh hummock creation experiment …

Analysis And Numerical Simulation Of Tumor Growth Models, Daniel Acosta Soba

Masters Theses and Doctoral Dissertations

In this dissertation we focus on the numerical analysis of tumor growth models. Due to the difficulty of developing physically meaningful approximations of such models, we divide the main problem into more simple pieces of work that are addressed in the different chapters. First, in Chapter 2 we present a new upwind discontinuous Galerkin (DG) scheme for the convective Cahn–Hilliard model with degenerate mobility which preserves the pointwise bounds and prevents non-physical spurious oscillations. These ideas are based on a well-suited piecewise constant approximation of convection equations. The proposed numerical scheme is contrasted with other approaches in several numerical experiments. …

The Future Of Brain Tumor Diagnosis: Cnn And Transfer Learning Innovations, Shengyuan Wang

Mathematics, Statistics, and Computer Science Honors Projects

For the purpose of improving patient survival rates and facilitating efficient treatment planning, brain tumors need to be identified early and accurately classified. This research investigates the application of transfer learning and Convolutional Neural Networks (CNN) to create an automated, high-precision brain tumor segmentation and classification framework. Utilizing large-scale datasets, which comprise MRI images from open-accessible archives, the model exhibits the effectiveness of the method in various kinds of tumors and imaging scenarios. Our approach utilizes transfer learning techniques along with CNN architectures strengths to tackle the intrinsic difficulties of brain tumor diagnosis, namely significant tumor appearance variability and difficult …