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Full-Text Articles in Physical Sciences and Mathematics

Development Of Platinum(Iv)-Gold(I)-Based Anticancer Agents, Javier E. Lopez-Hernandez Jun 2024

Development Of Platinum(Iv)-Gold(I)-Based Anticancer Agents, Javier E. Lopez-Hernandez

Dissertations, Theses, and Capstone Projects

Heterometallic compounds have emerged as prospective multitarget anticancer drugs. These species may display improved efficacy and physicochemical properties compared to the individual metallic fragments, while helping combat drug resistance by exerting effects on multiple pathways. In this thesis we describe the synthesis of new bi- and tri-metallic compounds based on platinum(IV) compounds containing FDA-approved platinum agents, and gold(I) derivatives with known anticancer properties. We demonstrate their toxicity and selectivity against a small panel of renal, bladder, ovarian, and breast cancer cell lines, as well as their synergistic effects. We have selected a trinuclear PtAu2compound containing the Pt(IV) core …


Positron Emission Tomography In Oncology And Environmental Science, Samantha Delaney Jun 2024

Positron Emission Tomography In Oncology And Environmental Science, Samantha Delaney

Dissertations, Theses, and Capstone Projects

The last half century has played witness to the onset of molecular imaging for the clinical assessment of physiological targets. While several medical imaging modalities allow for the visualization of the functional and anatomical properties of humans and living systems, few offer accurate quantitation and the ability to detect biochemical processes with low-administered drug mass doses. This limits how physicians and scientists may diagnose and treat medical issues, such as cancer, disease, and foreign agents.

A promising alternative to extant invasive procedures and suboptimal imaging modalities to assess the nature of a biological environment is the use of positron emission …


Crime Prediction Using Agent-Based Modeling, Yifei Gong Jun 2024

Crime Prediction Using Agent-Based Modeling, Yifei Gong

Dissertations, Theses, and Capstone Projects

Crime risk evaluation and crime prediction using agent-based modeling (ABM) have gained popularity in the field of computational criminology in recent years. Traditionally, researchers rely on statistical methods and machine learning models to predict crimes using historical data. ABM generates macro-level crime patterns in a bottom-up fashion by simulating the daily behaviors of autonomous entities, such as citizens and offenders. ABM takes into consideration the non-linear interactions between agents under complex social contexts. Currently, the comprehensive usage of ABM for criminological theory testing and urban policy evaluations calls for a unified software framework. In this research, we introduce CARESim, an …


Communication Challenges In Underwater Wireless Networks: Mac Protocols And Software Solutions, Dmitrii Dugaev Jun 2024

Communication Challenges In Underwater Wireless Networks: Mac Protocols And Software Solutions, Dmitrii Dugaev

Dissertations, Theses, and Capstone Projects

Underwater wireless networks (UWNs) represent a diverse and intriguing research domain, encompassing a wide array of scientific and industrial applications. This dissertation delves into the communication challenges at the Medium Access Control (MAC) layer within UWNs, stemming from the distinctive signal propagation conditions and the harshness of the deployment environment. The manuscript provides comprehensive coverage of key aspects of UWNs, including potential applications, communication protocols, methodologies employed in such networks, and existing software solutions that facilitate simulation, emulation, and real testbed scenarios for underwater research endeavors. Furthermore, this research introduces innovative software and communication solutions designed to facilitate the seamless …


Effect Of Magnetic Draping On Satellite Galaxies In Clusters, Vanessa Brown Jun 2024

Effect Of Magnetic Draping On Satellite Galaxies In Clusters, Vanessa Brown

Dissertations, Theses, and Capstone Projects

Galaxy evolution has been observed to be influenced by environment. Satellite galaxies orbiting within clusters can experience changes in morphology and composition through various mechanisms such as ram-pressure stripping (RPS), which removes a galaxy’s interstellar medium as it passes through the cluster via direct interaction with the hot intracluster medium gas. An open question is whether intracluster magnetic fields affect galaxy evolution, for example by forming a magnetic layer around infalling galaxies (called magnetic draping) and mitigating gas removal by RPS. Using the code GADGET-3, we compare global properties and mass distributions within identical cluster simulations run with and without …


Development And Application Of Magnus Expansion Based Propagators For Problems In Spectroscopy And Quantum Dynamics, Taner M. Ture Jun 2024

Development And Application Of Magnus Expansion Based Propagators For Problems In Spectroscopy And Quantum Dynamics, Taner M. Ture

Dissertations, Theses, and Capstone Projects

Stable and accurate numerical propagators of time-evolution equations in quantum mechanics are required to capture correct dynamical behavior, especially in the long time limit. Magnus expansion (ME) provides a general way to expand the real time propagator of a time dependent Hamiltonian within the exponential such that the unitarity is satisfied at any order. Integrators are developed by truncating the ME and using explicit integration of Lagrange interpolation formulas for the time dependent Hamiltonian within each time interval. The derived approximations are studied in a numerical test and compared to other available expressions. The sixth order expression is applied to …


Sigma_N-Correct Forcing Axioms, Benjamin P. Goodman Jun 2024

Sigma_N-Correct Forcing Axioms, Benjamin P. Goodman

Dissertations, Theses, and Capstone Projects

I introduce a new family of axioms extending ZFC set theory, the Sigma_n-correct forcing axioms. These assert roughly that whenever a forcing name a' can be forced by a poset in some forcing class Gamma to have some Sigma_n property phi which is provably preserved by all further forcing in Gamma, then a' reflects to some small name such that there is already in V a filter which interprets that small name so that phi holds. Sigma_1-correct forcing axioms turn out to be equivalent to classical forcing axioms, while Sigma_2-correct forcing axioms for Sigma_2-definable forcing classes are consistent relative to …


Unconventional Computing With Photonic Oscillator Networks, Mostafa Honari Latifpour Jun 2024

Unconventional Computing With Photonic Oscillator Networks, Mostafa Honari Latifpour

Dissertations, Theses, and Capstone Projects

The ever-increasing demand for data processing and the challenges in scaling traditional computing architectures are driving intensive research into alternative computing paradigms. Optical computing has garnered renewed attention since the 2010s, driven by its potential to accelerate specialized computational tasks such as combinatorial optimization and neural networks.

Coherent light sources including lasers and parametric oscillators have been around for decades and become indispensable tools in modern technology, but these photonic oscillators are also nonlinear dynamical systems that can exhibit emergent, complex phenomena, especially when coupled in arrays. These nonlinear optical systems have recently been shown to be capable of doing …


The Efficacy Of Using Machine Learning Techniques For Identifying And Classifying “Fake News”, Muhammad Islam Jun 2024

The Efficacy Of Using Machine Learning Techniques For Identifying And Classifying “Fake News”, Muhammad Islam

Dissertations, Theses, and Capstone Projects

In today's digital world, detecting fake news has emerged as a critical challenge, one that has significant effects on democracy and public discourse at large both regionally and globally. This research studies how diversity of news sources in training datasets affects how well machine learning models can classify fake vs true news. I used the Linear Support Vector Classification (LinearSVC) to create and compare two classification models: one was trained on a dataset that only had real news from a singular source, Reuters (Dataset 1), and the other was trained on a dataset that contained real news from Reuters, The …


Assessing Job Vulnerability And Employment Growth In The Era Of Large Language Models (Llms), Prudence P. Brou Jun 2024

Assessing Job Vulnerability And Employment Growth In The Era Of Large Language Models (Llms), Prudence P. Brou

Dissertations, Theses, and Capstone Projects

This paper explores the impact of Large Language Models (LLMs) and artificial intelligence (AI) on white-collar occupations in the context of job vulnerability and employment growth. Utilizing the Kaggle dataset "Occupation Salary and Likelihood of Automation," the study employs a data-driven approach to analyze trends across states. Through interactive data visualization, the project aims to provide actionable insights for affected workers, businesses, and policymakers navigating the changing dynamics of the workforce amidst technological advancements.


Using A Novel Chain Of Chemical, Crystallographic, And Isotopic Analytical Techniques To Examine The Formation Histories Of Features In Chondritic Meteorites And Orbicular Granites, Samuel P. Alpert Jun 2024

Using A Novel Chain Of Chemical, Crystallographic, And Isotopic Analytical Techniques To Examine The Formation Histories Of Features In Chondritic Meteorites And Orbicular Granites, Samuel P. Alpert

Dissertations, Theses, and Capstone Projects

Understanding the chemistry, crystallography, and isotopic variability of minerals allows us to place significant constraints on the formation history of their host rocks. These constraints provide insight into everything from the distribution of water in the solar system to the onset of plate tectonics. Electron beam instruments and ion probes are important tools used by modern geologists to obtain crystallographic, chemical, and isotopic data. Here I present a new workflow, using these instruments, combining wavelength dispersive spectrometry (WDS), backscattered electron (BSE) imaging, machine learning algorithms, electron backscatter diffraction (EBSD), and secondary ion mass spectroscopy (SIMS), to place quantitative constraints on …


Modeling Hydroxide In Classical Proton Hopping Simulations And Amyloid Beta Membrane Pores, Ankita Dutta Jun 2024

Modeling Hydroxide In Classical Proton Hopping Simulations And Amyloid Beta Membrane Pores, Ankita Dutta

Dissertations, Theses, and Capstone Projects

H3O+ and OH- ions display anomalously large diffusion coefficients, a property that is often attributed to their ability to perform structural diffusion which allow these ions to move through aqueous solutions by sequential proton transfers, also known as ‘Grotthuss hopping’. A rearrangement of the local solvation structure is known to be the prerequisite for proton transfer events via these ions. Studying this phenomenon using classical molecular dynamics simulations that do not allow bond rearrangements poses significant obstacles. Here we use a Monte Carlo augmented classical Molecular Dynamics method called the MOBHY algorithm which allows instantaneous changes in protonation states in …


Grazing Annual Pastures – Using Feed On Offer (Foo) As A Guide, Department Of Primary Industries And Regional Development, Western Australia Jun 2024

Grazing Annual Pastures – Using Feed On Offer (Foo) As A Guide, Department Of Primary Industries And Regional Development, Western Australia

Animal production and livestock factsheets

Grazing management in winter and spring in South West Western Australia (SW WA) can manipulate the quality, quantity and composition of pasture. These pasture changes can increase livestock feed efficiency and productivity, reduce insect populations and improve pasture persistence. Seasonal grazing based on feed on offer (FOO) is described here to maximise stocking rate and pasture production.

The Department of Primary Industries and Regional Development recommends using feed measurements and feed budgeting to increase productivity and reduce livestock health risks.


Boosting Winter Pasture Growth, Department Of Primary Industries And Regional Development, Western Australia Jun 2024

Boosting Winter Pasture Growth, Department Of Primary Industries And Regional Development, Western Australia

Grains and other field crops factsheets

Applying gibberellic acid or nitrogen fertiliser to pasture in winter can increase dry matter production of grasses and broadleaf weeds and help reduce feed shortages in winter.


The Cultivation Of Ulva Lactuca In Jambiani, Zanzibar: A Case Study, Jazmine R. Compton Jun 2024

The Cultivation Of Ulva Lactuca In Jambiani, Zanzibar: A Case Study, Jazmine R. Compton

Anthós

This case study explores the feasibility of Ulva lactuca cultivation in Jambiani, Zanzibar, Tanzania. The seaweed farming industry in Zanzibar is facing challenges related to climate change that have resulted in increased rates of crop failure and decreased production. Cultivation of the green algae Ulva lactuca has been suggested as a potential solution due to its tolerance to extreme environmental conditions. In collaboration with Marine Cultures, this project has tested different cultivation methods typically used for red algae (Rhodophyta) species. Experimental plots of Ulva lactuca were established in Jambiani, Zanzibar using the floating line and off- bottom methods. At the …


Speeding Up Coded Distributed Machine Learning, Xian Su Jun 2024

Speeding Up Coded Distributed Machine Learning, Xian Su

Dissertations, Theses, and Capstone Projects

The advancement of artificial intelligence has facilitated the generation of vast datasets, whose size often exceeds tens of terabytes. Meanwhile, machine learning has become the most important technique for big data analytics, and sophisticated models with thousands or even millions of parameters are designed to leverage big data. However, processing big data and training large models necessitate significant storage and computational resources, which has been a bottleneck in the development of artificial intelligence. Distributed computing, such as MapReduce, has been proposed to surmount the computational bottlenecks associated with single-machine analysis.

Although distributed computing harnesses the collective power of numerous less …


Amino-Modified Upcycled Biochar Achieves Selective Chromium Removal In Complex Aqueous Matrices, Kenneth Flores, Diego F. Gonzalez, Helia Magali Morales, Arnulfo Mar, Sergi Garcia-Segura, Jorge L. Gardea-Torresdey, Jason Parsons Jun 2024

Amino-Modified Upcycled Biochar Achieves Selective Chromium Removal In Complex Aqueous Matrices, Kenneth Flores, Diego F. Gonzalez, Helia Magali Morales, Arnulfo Mar, Sergi Garcia-Segura, Jorge L. Gardea-Torresdey, Jason Parsons

School of Earth, Environmental, & Marine Sciences Faculty Publications

Chromium pollution of groundwater sources is a growing global issue, which correlates with various anthropogenic activities. Remediation of both the Cr(VI) and Cr(III), via adsorption technologies, has been championed in recent years due to ease of use, minimal energy requirements, and the potential to serve as a highly sustainable remediation technology. In the present study, a biochar sorbent sourced from pineapple skins, allowed for the upcycling of agricultural waste into water purification technology. The biochar material was chemically modified, through a green amination method, to produce an efficient and selective adsorbent for the removal of both Cr(VI) and Cr(III) from …


Draft Final Quarterly Operations And Maintenance Report Butte Treatment Lagoon System – First Quarter 2024, Pioneer Technical Services, Inc. Jun 2024

Draft Final Quarterly Operations And Maintenance Report Butte Treatment Lagoon System – First Quarter 2024, Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Public Data Resources And Total Factor Productivity Of Enterprises: A Quasi-Natural Experiment Based On Local Government Data Opening, Wuping Wu, Qiheng Li, Liuyi Zhang, Yue Zhao Jun 2024

Public Data Resources And Total Factor Productivity Of Enterprises: A Quasi-Natural Experiment Based On Local Government Data Opening, Wuping Wu, Qiheng Li, Liuyi Zhang, Yue Zhao

Research Collection School Of Accountancy

The opening of public data is the government’s major strategic move to release the value of data factor. However, whether these data resources are used by the public to release their value needs to be empirically tested. Therefore, based on the perspective of high-quality development of firms, this paper examines the relation between open public data and firms’ total factor productivity so as to reflect the value of public data resources in driving force of promoting firms’ high-quality development. Taking A-share listed firms from 2010 to 2019 as samples, using a natural experiment based on the launch of the local …


Recursive Marix Game Analysis: Optimal, Simplified, And Human Strategies In Brave Rats, William A. Medwid Jun 2024

Recursive Marix Game Analysis: Optimal, Simplified, And Human Strategies In Brave Rats, William A. Medwid

Master's Theses

Brave Rats is a short game with simple rules, yet establishing a comprehensive strategy is very challenging without extensive computation. After explaining the rules, this paper begins by calculating the optimal strategy by recursively solving each turn’s Minimax strategy. It then provides summary statistics about the complex, branching Minimax solution. Next, we examine six other strategy models and evaluate their performance against each other. These models’ flaws highlight the key elements that contribute to the effectiveness of the Minimax strategy and offer insight into simpler strategies that human players could mimic. Finally, we analyze 123 games of human data collected …


Using Bayesian Multispecies Models To Evaluate Fish And Invertebrate Detection Probability And Distribution In The Hypersaline Bahia Grande Tidal Basin, Roy M. Ulibarri, Catherine M. Eckert, David Hicks, David Montagne, Brandon Jones, David R. Stewart Jun 2024

Using Bayesian Multispecies Models To Evaluate Fish And Invertebrate Detection Probability And Distribution In The Hypersaline Bahia Grande Tidal Basin, Roy M. Ulibarri, Catherine M. Eckert, David Hicks, David Montagne, Brandon Jones, David R. Stewart

School of Earth, Environmental, & Marine Sciences Faculty Publications

Objective

In 2000, the Laguna Atascosa National Wildlife Refuge acquired the Bahia Grande (Texas) management unit, a space that had lain barren and arid for 70 years. A large cooperative partnership launched a restoration project to replenish the basin and recover its original tidal hydrology. In 2005, the construction of a pilot channel successfully restored water throughout the basin, and plans to eventually widen the channel were developed. Our study aims to evaluate an estuarine habitat restoration by assessing ecological drivers and the impacts on species diversity.

Methods

We evaluated species richness, detection/occupancy rates, and species–habitat relationships, and we estimated …


Securing Tomorrow: Synergizing Change Management And Cybersecurity In The Digital Era, Sharon L. Burton Jun 2024

Securing Tomorrow: Synergizing Change Management And Cybersecurity In The Digital Era, Sharon L. Burton

Publications

In the rapidly evolving business environment of 2024, organizational change management (OCM) leaders face unprecedented challenges driven by technological advancements, digital transformation, the integration of remote work, and a heightened focus on sustainability. This study examines the efficacy of traditional OCM models in addressing these modern complexities. Through a qualitative methodology employing an extensive literature review, the research identifies vital issues such as resistance to change, digital transformation imperatives, the shift to remote and hybrid work models, and the imperative for sustainable and ethical business practices. The study posits that while classical OCM frameworks offer foundational insights, there is a …


Predicting Rheology Of Uv-Curable Nanoparticle Ink Components And Compositions For Inkjet Additive Manufacturing, Cameron D. Lutz Jun 2024

Predicting Rheology Of Uv-Curable Nanoparticle Ink Components And Compositions For Inkjet Additive Manufacturing, Cameron D. Lutz

Master's Theses

Inkjet additive manufacturing is the next step toward ubiquitous manufacturing by enabling multi-material printing that can exhibit various mechanical, electronic, and thermal properties. These characteristics are realized in the careful formulation of the inks and their functional materials, but there are many constraints that need to be satisfied to allow optimal jetting performance and build quality when used in an inkjet 3-D printer. Previous research has addressed the desirable rheology characteristics to enable stable drop formation and how the metallic nanoparticles affect the viscosity of inks. The contending goals of increasing nanoparticle-loading to improve material deposition rates while trying to …


Combining Cloud Architecting With Education, Sharon P. Pagidipati Jun 2024

Combining Cloud Architecting With Education, Sharon P. Pagidipati

Liberal Arts and Engineering Studies

I pursued the AWS Solutions Architect Professional Certification while applying my knowledge to build and revise technical solutions for an educational company known as EDFX.


Auditory Ace Mobile Application Capstone Review, Layla Smith Jun 2024

Auditory Ace Mobile Application Capstone Review, Layla Smith

University Honors Theses

This paper describes the development process and outcomes of my 2023-2024 Capstone Project, Auditory Ace, a self-directed auditory training mobile application for individuals with cochlear implants. Recognizing the limitations of current market offerings, Dr. Timothy Anderson created a Capstone project proposal to develop an accessible auditory training mobile application. The Capstone team that took on this proposal consisted of Darya Haines, Dustin Huynh, Jordan Nguyen, Nihar Koppolu, Scott Thorkelson, Sienna Day, and myself, Layla Smith. This paper is structured to follow the Agile software development methodology, which we used to develop Auditory Ace, reviewing in detail every major choice we …


The Cascading Effects Of Database Design, Liam Mccracken Jun 2024

The Cascading Effects Of Database Design, Liam Mccracken

University Honors Theses

This paper details how a relational database influenced the design of the rest of a software project. The software project in question is WonderTix, an open-source ticketing and donation platform for the use of Portland Playhouse under continuous development by teams of Portland State students as their computer science capstone project. The paper, a capstone review thesis, examines WonderTix as an instantiation of the Model-View-Controller design pattern, noting how the model, a relational database based on the SQL standard, influenced the design of the view and controller components. This influence is explored from three angles. First, when the implementation of …


Remediating History: A Review Of Restoration For Creeks Polluted From Historical Mining Sites, With The Red Boy Mine As A Primary Case Study, Kara Atiyeh Jun 2024

Remediating History: A Review Of Restoration For Creeks Polluted From Historical Mining Sites, With The Red Boy Mine As A Primary Case Study, Kara Atiyeh

University Honors Theses

I conducted a literature review to examine the key aspects of restoring watersheds affected by pollution from historical mining. This review is then applied to a case study discussion of the Red Boy Mine and Clear Creek remediation project in Granite, Oregon. The goal of this discussion is to explore how an analysis of site conditions along with current literature on management practices can help guide these projects. Thousands of abandoned hard rock mines remain throughout the country, and many pose serious environmental health effects. Heavy metals like cadmium, nickel, and copper are brought to the surface from mining activity, …


Virtual Field Environments Capstone Software Review, Ashton Sawyer Jun 2024

Virtual Field Environments Capstone Software Review, Ashton Sawyer

University Honors Theses

This is a review of the Virtual Field Environments computer science capstone project, sponsored by geology professor Rick Hugo. The tool aims to create and render VFEs, interactable 360° environments hosted on the web that are used as virtual field trips for K-12 students. This essay discusses the development process, including understanding requirements, tool and technology selection, problem-solving, and decision-making strategies. It also highlights the differences between the capstone and the other core computer science courses, and how those differences help to prepare students for the workforce. The project was completed over the course of twenty weeks by a team …


Lang2views Capstone: The Importance Of A Conscientious Team Lead, Joseph Wornath Jun 2024

Lang2views Capstone: The Importance Of A Conscientious Team Lead, Joseph Wornath

University Honors Theses

This review essay reflects the Lang2views capstone project from the perspective of a team lead. The Lang2views capstone project was a web-based user interface designed to simplify how the Lang2views corporation localizes videos into other languages for their clients. Our capstone group was split into three subgroups: front-end, back-end, and DevOps. The strategy for completing the project went through a major change midway through development wherein we changed our software development methodology from a more rigid Waterfall-type approach to a more flexible Agile methodology. Because of this, many of the initially planned features had to be reevaluated as out of …


Enhancing Robustness Of Machine Learning Models Against Adversarial Attacks, Ronak Guliani Jun 2024

Enhancing Robustness Of Machine Learning Models Against Adversarial Attacks, Ronak Guliani

University Honors Theses

Machine learning models are integral for numerous applications, but they remain increasingly vulnerable to adversarial attacks. These attacks involve subtle manipulation of input data to deceive models, presenting a critical threat to their dependability and security. This thesis addresses the need for strengthening these models against such adversarial attacks. Prior research has primarily focused on identifying specific types of adversarial attacks on a limited range of ML algorithms. However, there is a gap in the evaluation of model resilience across algorithms and in the development of effective defense mechanisms. To bridge this gap, this work adopts a two-phase approach. First, …