Physical Sciences and Mathematics Commons^™

Characterizations Of Bimetallic Silver-Copper Nanoparticles, Omar Lezcano

Undergraduate Honors Theses

The goal of this study was to characterize alloy nanoparticles with different bimetallic ratios of silver (Ag) and copper (Cu) by determining the composition and alloy structures. One specific objective was to determine how the composition affects the electrical properties of the nanoparticles in terms of electrical resistance and nanoparticle sintering. The desire for this study stems from the need to make conductive pastes for low-cost solar panel manufacturing. We performed experiments to develop the aqueous synthesis of core-shell bimetallic nanoparticles.

We investigated the room temperature sintering properties with the nanoparticles of varying compositions. The nanoparticles were characterized with several …

The Local Stability Of A Modified Multi-Strain Sir Model For Emerging Viral Strains, Miguel Fudolig, Reka Howard

Department of Statistics: Faculty Publications

We study a novel multi-strain SIR epidemic model with selective immunity by vaccination. A newer strain is made to emerge in the population when a preexisting strain has reached equilbrium. We assume that this newer strain does not exhibit cross-immunity with the original strain, hence those who are vaccinated and recovered from the original strain become susceptible to the newer strain. Recent events involving the COVID-19 virus shows that it is possible for a viral strain to emerge from a population at a time when the influenza virus, a well-known virus with a vaccine readily available, is active in a …

From Forests To Fish: Mercury In Mountain Lake Food Webs Influenced By Factors At Multiple Scales, Ariana M. Chiapella, Collin A. Eagles-Smith, Angela L. Strecker

Environmental Science and Management Faculty Publications and Presentations

Mountain lakes, while seemingly pristine, have been subjected to historical fish stocking practices and exposure to atmospherically deposited contaminants like mercury. Mercury bioaccumulation in these ecosystems varies widely due to strong environmental gradients, and there are complex, hierarchical factors that affect mercury transport and loading, methylmercury production, and food web biomagnification. We sought to assess how representative variables associated with watershed, lake, and food web-scale processes—specifically, catchment tree cover, lake benthic primary production, and fish diet, respectively—are associated with mercury concentrations in mountain lake fish. Mean fish mercury concentrations varied threefold between lakes, with nearshore tree cover and fish diet …

Methods For Generative Adversarial Output Enhancement, Michael B. Brodie

Theses and Dissertations

Generative Adversarial Networks (GAN) learn to synthesize novel samples for a given data distribution. While GANs can train on diverse data of various modalities, the most successful use cases to date apply GANs to computer vision tasks. Despite significant advances in training algorithms and network architectures, GANs still struggle to consistently generate high-quality outputs after training. We present a series of papers that improve GAN output inference qualitatively and quantitatively. The first chapter, Alpha Model Domination, addresses a related subfield of Multiple Choice Learning, which -- like GANs -- aims to generate diverse sets of outputs. The next chapter, CoachGAN, …

On Improving The Memorability Of System-Assigned Recognition-Based Passwords, Mahdi Nasrullah Al-Ameen, Sonali T. Marne, Kanis Fatema, Matthew Wright, Shannon Scielzo

Computer Science Faculty and Staff Publications

User-chosen passwords reflecting common strategies and patterns ease memorization but offer uncertain and often weak security, while system-assigned passwords provide higher security guarantee but suffer from poor memorability. We thus examine the technique to enhance password memorability that incorporates a scientific understanding of long-term memory. In particular, we examine the efficacy of providing users with verbal cues—real-life facts corresponding to system-assigned keywords. We also explore the usability gain of including images related to the keywords along with verbal cues. In our multi-session lab study with 52 participants, textual recognition-based scheme offering verbal cues had a significantly higher login success …

Data From: Anomalous Electron Temperature, Bela G. Fejer

Browse all Datasets

Anomalous Electron Temperatures in the evening equatorial ionosphere. These are outputs of simulations from the semi-empirical SAMI2-PE (Varney et al. 2012) for the night of the 02 and 05 August 2011.

Relationships Between In-Situ Tests And Soil Cyclic Strength For Earthquake Hazard Characterization In The Pacific Northwest, Tanner Scott Bryantt

Dissertations and Theses

Strong earthquake shaking is a natural hazard threat in the Pacific Northwest. Soil failure due to strong earthquake shaking -- known as cyclic soil failure or liquefaction -- is expected to cause large ground deformations and damage to roads, bridges, and other civil infrastructure. Cyclic soil strength (CRR) is often characterized with in-situ geotechnical tests including the cone penetration test (CPT). Relationships between CRR and in-situ test data are not well established for soils in the Pacific Northwest. Portland State University, in partnership with New Albion Geotechnical has compiled a database of cyclic lab tests for Pacific Northwest soils to …

Structures And Characteristics Of Macromolecular Interactions In Gas Phase Using Fourier-Transform Ion Cyclotron Resonance Mass Spectrometry, Jiewen Shen

Theses and Dissertations

This dissertation investigates non-covalent macromolecular chemistry using Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS) based techniques. The included studies reveal the impact of molecular structure on conformation and binding energetics. Supramolecules that might be too heavy to be dissociated in single collision-induced dissociation (CID) were dissociated using sustained off-resonance collision induced dissociation (SORI-CID) techniques. Relative binding energies and thresholds were evaluated for various macromolecular host-guest systems. Besides the non-covalent binding energies, conformation characterization was undertaken by a novel method to determine collision cross sectional areas using FTICR (CRAFTI, and multi-CRAFTI), initially developed by the Dearden lab. The systems chosen …

Heavy Metal Pb Stress On Germination And Growth Of 5 Clover Varieties, Zhenzhong Sun, Qiao Wei, Jun Yin

IGC Proceedings (1993-2023)

No abstract provided.

Maintaining Grassland Biodiversity While Controlling The Shrub Rhus Glabra, James Stubbendieck, Kay L. Kottas

IGC Proceedings (1993-2023)

No abstract provided.

Eco-Politics Of Rangeland Management In The Hindu Kush-Himalayan Region: Articulating Ecology Into Food Sovereignty, Environmental Security, Development And Peace For A Sustainable World, Vir Singh

IGC Proceedings (1993-2023)

No abstract provided.

Desertification Reasons, Endangering And Tendency In China's Land, Yongjie Shi, Fuping Tian, Yuan Lu, Qing Song

IGC Proceedings (1993-2023)

No abstract provided.

Biogeocenotechnology Of Restoration And Increase Of Efficiency For Degraded Pasture Ecosystems In Arid Regions Of Central Asia And Russia, Zebri Shamsutdinov, Nariman Shamsutdinov

IGC Proceedings (1993-2023)

No abstract provided.

Restoring Rain Use Efficiency To An Incised Upland Valley System In Namibia Using Filters And Ecosystem Management Understanding (Emu) Principles, K. Shamathe, H. J. R. Pringle, I. Zimmermann

IGC Proceedings (1993-2023)

No abstract provided.

Dark Iron-Catalyzed Reactions In Acidic And Viscous Aerosol Systems Efficiently Form Secondary Brown Carbon, Hind A. Al-Abadleh, Md Sohel Rana, Wisam Mohammed, Marcelo I. Guzman

Chemistry Faculty Publications

Iron-driven secondary brown carbon formation reactions from water-soluble organics in cloud droplets and aerosols create insoluble and soluble products of emerging atmospheric importance. This work shows, for the first time, results on dark iron-catalyzed polymerization of catechol forming insoluble black polycatechol particles and colored water-soluble oligomers under conditions characteristic of viscous multicomponent aerosol systems with relatively high ionic strength (I = 1–12 m) and acidic pH (∼2). These systems contain ammonium sulfate (AS)/nitrate (AN) and C3–C5 dicarboxylic acids, namely, malonic, malic, succinic, and glutaric acids. Using dynamic light scattering (DLS) and ultra high pressure liquid chromatography-mass spectrometry (UHPLC-MS), …

An Overview Of The Effect Of Bioaerosol Size In Coronavirus Disease 2019 Transmission, Marcelo I. Guzman

Chemistry Faculty Publications

The fast spread of coronavirus disease 2019 (COVID-19) constitutes a worldwide challenge to the public health, educational and trade systems, affecting the overall well-being of human societies. The high transmission and mortality rates of this virus, and the unavailability of a vaccine or treatment, resulted in the decision of multiple governments to enact measures of social distancing. Such measures can reduce the exposure to bioaerosols, which can result in pathogen deposition in the respiratory tract of the host causing disease and an immunological response. Thus, it is important to consider the validity of the proposal for keeping a distance of …

Walking The Walk

In The Loop

DePaul's College of Computing and Digital Media has several programs that engage students in enjoyable and educational endeavors that build their skill sets, confidence, and connections. The School of Cinematic Arts has partnered for several years with the Chicago Housing Authority (CHA) on a program that pays youth residents of CHA housing to participate in documentary filmmaking, screenwriting and design. DeSports involves students at two Chicago Public Schools (CPS) in e-sports to develop collaboration, communication and critical-thinking skills. Middle-school girls in CPS participate STEM-oriented pursuits as part of Digital Youth Divas.

Stem Teacher Database, Veronica Buss

Honors Theses

The College of Engineering and Applied Sciences (CEAS) Recruitment web application provides access to recruitment information for the Manager of Recruitment and Outreach and those who also use the spreadsheet file with their current data. This database is a functional database for the WMU college of engineering and applied sciences’ recruiters to organize their data on STEM teachers from the feeder high schools of WMU. The app provides an interface for its users to filter and search the data they have compiled to create recruitment mailing reports. The main purpose of this app was to facilitate the retrieval and upkeep …

School District Boundaries Map, Nick Huffman

Honors Theses

The purpose of this project is to provide a school district boundary mapping feature to a product sold by Level Data called SDVS, which is a plugin used by districts inside of PowerSchool. Using primarily the features offered by Mapbox, We have implemented a React component that is capable of plotting useful data points related to a student and their school district on a map. The tool is designed to be used primarily by school administrators to determine whether or not a student lives within their district boundaries. The application uses a dataset that is provided by the NCES to …

Westbound, Genevieve Nicolow

Honors Theses

Westbound is a twenty-five chapter novella that aims to demonstrate ways in which creative writers can use climate fiction to overcome psychological barriers to act on climate change. The narrative follows Cassie, a character loosely based on a relative of its author, living in a future version of the United States that has been ravaged by climate change and its indirect consequences.

In the novella, Cassie and her mother Nia set out on a cross-country road trip as a climate disaster looms. The narrative explores their relationship and that with Cassie’s estranged father, the implications of projected ecological changes under …

Structural Determinants Of Flavin Dynamics In A Class B Monooxygenase, Ashley C. Campbell, Reeder Robinson, Didier Mena-Aguilar, Pablo Sobrado, John J. Tanner

Chemistry Faculty Research & Creative Works

The ornithine hydroxylase known as SidA is a class B flavin monooxygenase that catalyzes the first step in the biosynthesis of hydroxamate-containing siderophores in Aspergillus fumigatus. Crystallographic studies of SidA revealed that the FAD undergoes dramatic conformational changes between out and in states during the catalytic cycle. We sought insight into the origins and purpose of flavin motion in class B monooxygenases by probing the function of Met101, a residue that contacts the pyrimidine ring of the in FAD. Steady-state kinetic measurements showed that the mutant variant M101A has a 25-fold lower turnover number. Pre-steady-state kinetic measurements, pH profiles, and …

Eigenvalues Of Differential Operators And Nontrivial Zeros Of L-Functions, Dongsheng Wu

Theses and Dissertations

The Hilbert-P\'olya conjecture asserts that the non-trivial zeros of the Riemann zeta function $\zeta(s)$ correspond (in a certain canonical way) to the eigenvalues of some positive operator. R. Meyer constructed a differential operator $D_-$ acting on a function space $\H$ and showed that the eigenvalues of the adjoint of $D_-$ are exactly the nontrivial zeros of $\zeta(s)$ with multiplicity correspondence. We follow Meyer's construction with a slight modification. Specifically, we define two function spaces $\H_\cap$ and $\H_-$ on $(0,\infty)$ and characterize them via the Mellin transform. This allows us to show that $Z\H_\cap\subseteq\H_-$ where $Zf(x)=\sum_{n=1}^\infty f(nx)$. Also, the differential operator …

Metalearning By Exploiting Granular Machine Learning Pipeline Metadata, Brandon J. Schoenfeld

Theses and Dissertations

Automatic machine learning (AutoML) systems have been shown to perform better when they use metamodels trained offline. Existing offline metalearning approaches treat ML models as black boxes. However, modern ML models often compose multiple ML algorithms into ML pipelines. We expand previous metalearning work on estimating the performance and ranking of ML models by exploiting the metadata about which ML algorithms are used in a given pipeline. We propose a dynamically assembled neural network with the potential to model arbitrary DAG structures. We compare our proposed metamodel against reasonable baselines that exploit varying amounts of pipeline metadata, including metamodels used …

The Impact Of Shigeru Miyamoto On The Game Design Industry, Luan Tran

ART 108: Introduction to Games Studies

Nintendo started as a small company in the 1970s that sold playing cards. Having seen the exemplary gift in his son, Miyamoto's father arranged for an interview with the president of Nintendo Hiroshi Yamauchi. Consequently, Miyamoto got a position in 1977 as an apprentice in the planning department after showing his toy creations to the president. He became the first Nintendo artist as he helped create the art for the first original coin-operated arcade game. The approach demonstrated his innate abilities that would help him become the ultimate guru in the industry. Through individual discovery, Miyamoto has managed to produce …

Iron(Iii)-Bipyridine Incorporated Metal–Organic Frameworks For Photocatalytic Reduction Of Co2 With Improved Performance, Yuan-Ping Wei, Sizhuo Yang, Peng Wang, Jin-Han Guo, Jier Huang, Wei-Yin Sun

Chemistry Faculty Research and Publications

Metal–organic frameworks (MOFs) represent an emerging class of platforms to assemble single site photocatalysts for artificial photosynthesis. In this work, we report a new CO₂ reduction photocatalyst (UiO-68-Fe-bpy) based on a robust Zr(IV)-MOF platform with incorporated Fe(bpy)Cl₃ (bpy refers to the 4′-methyl-[2,2′-bipyridine] moiety) via amine–aldehyde condensation. We show that this hybrid catalyst can reduce CO₂ to form CO under visible light illumination with excellent selectivity and enhanced activity with respect to its parent MOF and corresponding homogeneous counterpart. Using steady state and transient absorption (TA) spectroscopy, we show that the enhanced photocatalytic activity of UiO-68-Fe-bpy is attributed …

Galectin-1 Improves Sarcolemma Repair And Decreases The Inflammatory Response In Lgmd2b Models, Matthew F. Rathgeber

Theses and Dissertations

Limb-girdle muscular dystrophy type 2B (LGMD2B) is caused by mutations in the dysferlin gene, resulting in non-functional dysferlin, a key protein found in muscle membrane. Treatment options available for patients are chiefly palliative in nature and focus on maintaining ambulation. Our hypothesis is that galectin-1 (Gal-1), a soluble carbohydrate binding protein, increases membrane repair capacity, myogenic potential, M2 macrophage polarization and decreases NF-κB inflammation in dysferlin-deficient models. To test this hypothesis, we used recombinant human galectin-1 (rHsGal-1) to treat dysferlin-deficient models. We show that rHsGal-1 treatments of 48 h-72 h promotes myogenic maturation as indicated through improvements in size, myotube …

Novel Αvβ6 Inhibitor Reduces Fibrotic Progression In Idiopathic Pulmonary Fibrosis Murine Model, Rebecca C. Viazzo Winegar

Theses and Dissertations

Idiopathic pulmonary fibrosis (IPF) is one of the most aggressive and severe interstitial lung diseases (ILDs) for which there is no cure. IPF is characterized by an excessive accumulation of fibroblasts which secrete an abundance of extracellular proteins such as collagen. These processes lead to repetitive tissue scarring and fibrosis in the lung parenchyma. As a result, lungs become rigid limiting oxygen intake and gas exchange. Once diagnosed, IPF is fatal within 2-3 years. There is no known cause or proven treatment that significantly improves outcomes. Although the cause is unknown, the current model of IPF suggests that an overactive …

Wildfire Risk Assessment For A Municipal Watershed In Western Oregon, Usa: Methods For Projecting The Impact Of Mid-21st Century Climate Change On Wildfire Hazard, Andy Mcevoy

Dissertations and Theses

In the western United States, climate change is projected to lead to significant changes in regional wildfire regimes. Historically, forests west of the Cascade crest in Oregon and Washington, USA (westside) have been characterized by low-frequency wildfire events, but climate change projections indicate that wildfire could become a more common disturbance, altering ecological processes and impairing ecosystem services like surface water quality and quantity. Wildfire risk assessments based on simulation models have been used in high frequency fire regimes to evaluate contemporary and future risk, but present unique challenges in westside forests because characteristic low annual burn probabilities result in …

Thermal Time Requirements For Leaf Appearance Of Frontier Balansa Clover, D. P. Monks, D. J. Moot

IGC Proceedings (1993-2023)

No abstract provided.

The Effect Of Rapid Paddock Movement On Yearling Steer Weight Gain And Forage Condition In North‐Central Nebraska, Usa, D. G. Mickey Steward

IGC Proceedings (1993-2023)

No abstract provided.