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Articles 10441 - 10470 of 291657

Full-Text Articles in Physical Sciences and Mathematics

Autonomous Uav Swarm Formation Utilizing Gradient-Driven Contour Mapping For Radiation Source Localization, Edgar Amalyan Aug 2025

Autonomous Uav Swarm Formation Utilizing Gradient-Driven Contour Mapping For Radiation Source Localization, Edgar Amalyan

UNLV Theses, Dissertations, Professional Papers, and Capstones

This thesis presents a drone swarm for radiation mapping to aid source localization. The Department of Energy advocates employing UAVs for this task, but existing approaches remain inefficient and impractical in real-world scenarios. Three custom drones are built and flight-tested. A control algorithm to follow a contour, a constant-intensity path, is designed using a gradient fit. By knowing the source’s direction, the drone swarm can fly in the optimal trajectory at every step, leaving nothing to assumption. A program is created that implements formation flight and autonomous navigation. It is tested via a software-in-the-loop simulation utilizing radiation sources and detectors …


Mechanisms Of Gold Enrichment In Seafloor Massive Sulfide Deposits: A Study On The Higashi-Aogashima Hydrothermal Field, Claudia Martinez Aug 2025

Mechanisms Of Gold Enrichment In Seafloor Massive Sulfide Deposits: A Study On The Higashi-Aogashima Hydrothermal Field, Claudia Martinez

UNLV Theses, Dissertations, Professional Papers, and Capstones

The study of Seafloor Massive Sulfides (SMS) deposit formation is vital for assessing both the economic potential and environmental risks posed by future marine mining projects. Metal-rich SMS deposits form in hydrothermal vent systems within tectonically active regions, such as back-arc basins, where faults enhance crustal permeability, enabling fluid migration driven by magmatic heat sources at depth in the crust. Currently our understanding of SMS formation processes is based on bulk-rock geochemical and isotopic data, lacking the necessary spatial and temporal resolution to understand ore forming processes. As a result, critical gaps remain in understanding the exact mechanisms responsible for …


Analysis Of Leak Testing Planning For Carbon Dioxide Piping Systems In The Development Of Carbon Capture, Utilization, And Storage Facilities In The Bintuni Basin, Devi Sentiani, Akhmad Herman Yuwono Professor Aug 2025

Analysis Of Leak Testing Planning For Carbon Dioxide Piping Systems In The Development Of Carbon Capture, Utilization, And Storage Facilities In The Bintuni Basin, Devi Sentiani, Akhmad Herman Yuwono Professor

Journal of Materials Exploration and Findings

Carbon Capture, Utilization, and Storage (CCUS) technologies have become a key strategic response to global efforts to reduce CO2 emissions. This study presents a leak testing strategy designed for a carbon dioxide (CO₂) piping system as part of a Carbon Capture, Utilization, and Storage (CCUS) project in the Bintuni Basin, West Papua, Indonesia. This study aims to ensure the system is properly prepared before commissioning by designing a leak test plan that is both practical and technical, based on ASME B31.3, ASME PCC-2, and API STD 520 Part 1. We conducted the process, which involves identifying the system boundaries, …


Postglacial Erosional Response Of A Permafrost Landscape Across Decadal To Millenial Timescales, Aklavik Range, Arctic Canada, Bailey J. Nordin Aug 2025

Postglacial Erosional Response Of A Permafrost Landscape Across Decadal To Millenial Timescales, Aklavik Range, Arctic Canada, Bailey J. Nordin

Dartmouth College Master’s Theses

Rapid warming and permafrost thaw across Arctic landscapes are projected to drastically accelerate local erosion rates and sediment fluxes to downstream systems and the communities that rely on them. However, interpreting this signal of change first requires disentangling the relative contributions of postglacial landscape responses, periglacial processes, and modern warming to observed changes in erosion. To explore this problem, we combine a suite of geochronometers to examine erosion and deposition rates over timescales of 102–107 years across a periglacial alluvial fan and catchment system on the former margin of the Laurentide Ice Sheet in the Aklavik Range …


Multimodal Characterization Of Systems-Level Robustness In The Cellular Organelle Network, Aline Arra Aug 2025

Multimodal Characterization Of Systems-Level Robustness In The Cellular Organelle Network, Aline Arra

Arts & Sciences Graduate Student Theses and Dissertations

Eukaryotic cells house mesoscopic and macroscopic complex systems that work in tandem for proper cellular function. A defining feature of eukaryotic cells is their mesoscopic network of membrane bound compartments called organelles. While each type of organelle has their own individual functions, there are vital cellular processes that come from the interactions between them, such as organelle biogenesis and metabolic regulation. A central question in cellular biophysics is to what degree is cellular function robust or fragile to breaks in the organelle network. These interactions can be explored by genetically deleting inter-organelle protein tethers called organelle contact sites. Here we …


Unveiling Mysteries Of The Universe: Axions, Sterile Neutrinos, And Curvatons, Takuya Okawa Aug 2025

Unveiling Mysteries Of The Universe: Axions, Sterile Neutrinos, And Curvatons, Takuya Okawa

Arts & Sciences Graduate Student Theses and Dissertations

The Standard Model of particle physics and cosmology is amazingly successful in describing our universe, from at present to even tracing back to just one second after its birth. Yet, it is known to be incomplete. For instance, (i) more than four-fifths of matter in the universe is unknown, (ii) quantum chromodynamics is unnaturally of CP-preserving nature, (iii) the universe produced baryonic particles by nearly equal but slightly larger amount compared to anti-baryonic particles, and (iv) the physics at very early times is not understood yet. This thesis first briefly summarizes the Standard Model of particle physics and cosmology, and …


From Coastal Retreat To Seaward Growth: Emergent Behaviors From Paired Community Beach Nourishment Choices, Jorge Lorenzo-Trueba, Arye Janoff, Oshane Thomas, Di Jin, Porter Hoagland, Andrew Ashton Aug 2025

From Coastal Retreat To Seaward Growth: Emergent Behaviors From Paired Community Beach Nourishment Choices, Jorge Lorenzo-Trueba, Arye Janoff, Oshane Thomas, Di Jin, Porter Hoagland, Andrew Ashton

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Coastal communities often address shoreline erosion through beach nourishment, adding externally sourced sand to widen beaches for recreation and property protection. While nourishment enhances beachfront property values, the need for periodic maintenance creates interdependencies where the actions of neighboring communities affect local shoreline dynamics. Using a coupled model of two neighboring communities, we examine the interplay between community nourishment decisions and the redistribution of nourishment sand. We find that the value a community places on wider beaches not only influences their propensity to nourish, but also their and their neighbors' nourishment efficiency and net benefits. Communities that nourish more frequently …


An Evidence-Based Intervention To Increase Trypanosoma Cruzi, A Neglected Parasitic Infection, Diagnosis In Rural And Moderate-Size-City Us Clinics, M K. Lynn, Hunter M. Boehme, Jeffrey Hall, Patrick Kent, Alain H. Litwin, Quang H. Pham, Melissa Nolan Ph.D., Mph, Prisma Chagas Team Aug 2025

An Evidence-Based Intervention To Increase Trypanosoma Cruzi, A Neglected Parasitic Infection, Diagnosis In Rural And Moderate-Size-City Us Clinics, M K. Lynn, Hunter M. Boehme, Jeffrey Hall, Patrick Kent, Alain H. Litwin, Quang H. Pham, Melissa Nolan Ph.D., Mph, Prisma Chagas Team

Faculty Publications

Background

Chagas disease is a chronic, insidious parasitic infection (Trypanosoma cruzi) that slowly develops to irreversible organomegaly over several decades. The disease is traditionally acquired in endemic Latin American countries during childhood; < 1% of foreign-born adult residents in the United States have been diagnosed or treated with this potentially fatal disease. Low physician knowledge is a primary factor leading to misdiagnosis.

Methods

Starting in April 2022, a 4-part T cruzi clinical education intervention began, which included (i) 2 grand rounds presentations to >100 internal medicine providers; (ii) implementation of a “clinical Chagas champions program” incorporating 14 key clinical staff at varying departments and administrative levels educated on their specific role related to T cruzi screening, diagnosis confirmation, clinical management, and medical billing; ( …


Time-Evolved Constant Voltage Conductivity Measurements Of Common Spaceborne Polymeric Materials, Brian Wood, David King, Jr Dennison Aug 2025

Time-Evolved Constant Voltage Conductivity Measurements Of Common Spaceborne Polymeric Materials, Brian Wood, David King, Jr Dennison

Journal Articles

Long-duration current measurements were made for low-density polyethylene (LDPE), polyimide (PI), polyether ether ketone (PEEK), and biaxially oriented polypropylene (BOPP) to determine their bulk conductivity near room temperature as a function of time. These common thin-film spacecraft material samples were vacuum baked to remove moisture and volatile contaminants to better simulate space conditions. The constant voltage conductivity (CVC) method used a very stable, low-noise dc voltage source and measured the resulting current in a parallel plate geometry. Due to the extremely low conductivity of these four polymeric materials, extended experiments of up to ten days were necessary to establish equilibrium …


Advanced Robotic Multimodal Imaging With Real-Time Motion Compensation For Dynamic Structural Health Monitoring, George Papaioannou, Christos Mitrogiannis, Mark Schweitzer, Maria Pappa, Pegah Khosravi, Apostolos Karantanas, Chris Ruberg, Shawn Owens, Nikolaos Michailidis Aug 2025

Advanced Robotic Multimodal Imaging With Real-Time Motion Compensation For Dynamic Structural Health Monitoring, George Papaioannou, Christos Mitrogiannis, Mark Schweitzer, Maria Pappa, Pegah Khosravi, Apostolos Karantanas, Chris Ruberg, Shawn Owens, Nikolaos Michailidis

Publications and Research

Modern composite materials promise superior performance and load-bearing capabilities, yet evaluating their structural integrity remains challenging. Current testing methods, such as visual, thermographic, ultrasonic, optical, electromagnetic, terahertz, shearography, X-ray, and neutron imaging, are hampered by long scan durations, limited field of view, suboptimal accuracy, and high costs, particularly when applied to large structures.

This paper addresses these issues by introducing a novel robotic multimodal imaging system that overcomes the limitations of traditional methods. This system dynamically captures both static and dynamic properties of materials using advanced motion compensation techniques. By integrating multiple radiographic modalities into a coordinated robotic platform, it …


Re: Butte Mine Flooding Site Cd, Cv 02-35 Bu-Rfc, 2025 Second Quarter Report, Mark Thompson, Dave Griffis Aug 2025

Re: Butte Mine Flooding Site Cd, Cv 02-35 Bu-Rfc, 2025 Second Quarter Report, Mark Thompson, Dave Griffis

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Career: Algebra And Representation Theory For Non-Semisimple Topological Field Theory, Matthew Young Aug 2025

Career: Algebra And Representation Theory For Non-Semisimple Topological Field Theory, Matthew Young

Funded Research Records

No abstract provided.


Using The Epic (Exposure, Persuasion, Identification, And Commitment) To Develop A Measure Of Student Buy-In To Laboratory Learning Goals, Elizabeth Blanche Vaughan, A. Montoya-Cowan, Jack Barbera Aug 2025

Using The Epic (Exposure, Persuasion, Identification, And Commitment) To Develop A Measure Of Student Buy-In To Laboratory Learning Goals, Elizabeth Blanche Vaughan, A. Montoya-Cowan, Jack Barbera

Chemistry Faculty Publications and Presentations

Buy-in has been described as the series of judgements students make when deciding to engage with a pedagogical practice. Buy-in to pedagogical practices is known to have a meaningful impact on students’ engagement in learning environments, making it a construct of interest for researchers and practitioners. This study develops a measure of student buy-in to faculty defined laboratory learning goals by adapting an existing measure which operationalizes the construct in terms of Exposure, Persuasion, Identification, and Commitment (EPIC). The adapted measure presented in this study, deemed the EPIC-LaG (Laboratory Goals), was developed using learning goals for general and organic chemistry …


Awaiting The Colorado River 24-Month Study, John Fleck, Anne Castle, Eric Kuhn, Jack Schmidt, Kathryn Sorensen, Katherine Tara Aug 2025

Awaiting The Colorado River 24-Month Study, John Fleck, Anne Castle, Eric Kuhn, Jack Schmidt, Kathryn Sorensen, Katherine Tara

The Traveling Wilburys of the Colorado River

No abstract provided.


Relational Observables, Quiddities, And Structural Realism, Emily Adlam Aug 2025

Relational Observables, Quiddities, And Structural Realism, Emily Adlam

Mathematics, Physics, and Computer Science Faculty Articles and Research

In this article, I argue that modern spacetime physics causes problems for a number of traditional accounts of modality, but also offers important new ideas about the connection between modal and non-modal features of reality. I suggest that recent work on relational observables in general relativity and quantum gravity can help us understand how non-modal features of reality could arise from modal features of reality within some form of modal ontic structural realism. In particular, I argue that the notion of an ‘internal view,’ as employed in the partial/complete observables formalism and the quantum reference frame formalism, is an important …


Ocean And Coastal Acidification Monitoring Priorities For The Northeast Us And Eastern Canada, Christopher Hunt, Austin Pugh, Jake Kritzer, Samantha Siedlecki, Kumiko Azetsu-Scott, Parker Gassett, Diane Lavoie, Adam Pimenta, Amy Trice, Elizabeth Turner Aug 2025

Ocean And Coastal Acidification Monitoring Priorities For The Northeast Us And Eastern Canada, Christopher Hunt, Austin Pugh, Jake Kritzer, Samantha Siedlecki, Kumiko Azetsu-Scott, Parker Gassett, Diane Lavoie, Adam Pimenta, Amy Trice, Elizabeth Turner

Faculty Publications

The Interagency Working Group on Ocean Acidification Monitoring Prioritization Plan 2024 calls for Coastal Acidification Networks to identify the ocean and coastal acidification (OCA) monitoring needs most important for their regions. The Northeast Coastal Acidification Network (NECAN) organized a webinar series to study regional needs, which culminated with a workshop in November 2023. This workshop led to the identification of six priority new Monitoring Needs in addition to the maintenance of current monitoring efforts:

• Improve spatial and temporal scale of monitoring co-located OCA variables and biological measurements to better resolve variability of acidification dynamics in concert with biological processes …


2025 August 14 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University Aug 2025

2025 August 14 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Weekly Drought Summaries

No abstract provided.


From Anorthosite To Silicic Volcanics: Photometry, Composition, And Buoyancy Of Crustal Rock Types On The Moon, Emily Margaret Culley Aug 2025

From Anorthosite To Silicic Volcanics: Photometry, Composition, And Buoyancy Of Crustal Rock Types On The Moon, Emily Margaret Culley

Arts & Sciences Graduate Student Theses and Dissertations

To better constrain the formation and evolution of the lunar crust, this dissertation addresses two key aspects of lunar crustal formation: the primary feldspathic crust, formed during solidification of an ancient lunar magma ocean (LMO), and non-mare silicic volcanic constructs, which represent either secondary or tertiary crustal formation processes. Specifically, we performed photometry on Lunar Reconnaissance Orbiter Camera (LROC) Narrow Angle Camera (NAC) images to determine the single-scattering albedo (SSA) of surface features that expose these two non-mare crustal rock types. Using digital terrain models (DTMs) derived from LROC NAC images of each analysis region, we accounted for potential topographic …


Re: Butte Priority Soils Operable Unit (Bpsou) Draft Final Bres No. 35 Del Monte Reclamation Improvement Field Sampling Plan (Fsp), Mike Mcanulty Aug 2025

Re: Butte Priority Soils Operable Unit (Bpsou) Draft Final Bres No. 35 Del Monte Reclamation Improvement Field Sampling Plan (Fsp), Mike Mcanulty

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Re: Butte Priority Soils Operable Unit Revised Draft Final Reclamation Improvement Sites Field Sampling And Investigation Plan (Fsp): Bres No. 45 – Garfield Response To Agency Comments Received June 28, 2024, Mike Mcanulty Aug 2025

Re: Butte Priority Soils Operable Unit Revised Draft Final Reclamation Improvement Sites Field Sampling And Investigation Plan (Fsp): Bres No. 45 – Garfield Response To Agency Comments Received June 28, 2024, Mike Mcanulty

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Developing A Course-Based Undergraduate Research Experience For Chem 122, Melanie J. Harvey Phd Aug 2025

Developing A Course-Based Undergraduate Research Experience For Chem 122, Melanie J. Harvey Phd

Sabbatical Projects

Sabbatical presentation from a 2022 Sabbatical


Cybersecurity: Digital Stewardship In A Violent World, Rocky K. C. Chang Aug 2025

Cybersecurity: Digital Stewardship In A Violent World, Rocky K. C. Chang

University Faculty Publications and Creative Works

This paper defines cybersecurity based on the principle of biblical stewardship. The focus of this principle is God, not the technologies, who is the creator and owner of cyberspace and everything in it. Humankind is called by God to steward them by protecting the digital property of our neighbors in cyberspace from malicious attacks. In the context of cybersecurity, a neighbor can be any individual cyber user, practitioner, educator, organization, tech company, or even hacker. However, as argued from the perspectives of human sin and human finitude, the defending stewards can never win over evil in this spiritual battle. Instead, …


Butte Priority Soils Operable Unit (Bpsou) Draft Final Reclamation Improvement Sites Field Sampling And Investigation Plan (Fsp): Bres No. 18 – Walkerville Ballfield, Mike Mcanulty Aug 2025

Butte Priority Soils Operable Unit (Bpsou) Draft Final Reclamation Improvement Sites Field Sampling And Investigation Plan (Fsp): Bres No. 18 – Walkerville Ballfield, Mike Mcanulty

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Computational Modeling Of Magnetic Field Interaction With Superconductors Under High-Field And High-Dissipation Conditions: A Tdgl Approach Applied To Nb And Nb3sn, Aiden Victor Harbick Aug 2025

Computational Modeling Of Magnetic Field Interaction With Superconductors Under High-Field And High-Dissipation Conditions: A Tdgl Approach Applied To Nb And Nb3sn, Aiden Victor Harbick

Theses and Dissertations

Superconducting radiofrequency (SRF) cavities are essential components in modern particle accelerators, enabling the efficient acceleration of charged particles for various applications in physics, medicine, materials science, and beyond. The performance of these cavities is significantly influenced by the properties of superconducting materials, such as niobium (Nb) and triniobium-tin (Nb3Sn), and the defects and surface features present within the material. This dissertation presents a computational study focused on understanding the behavior of SRF cavities, using a sample-specific time-dependent Ginzburg-Landau (TDGL) framework to simulate their performance under realistic material conditions. The research integrates experimental data and density functional theory (DFT) calculations to …


Re: Butte Priority Soils Operable Unit (Bpsou) Final Insufficiently Reclaimed Sites Field Sampling And Investigation Plan (Fsp) For Ur-19 – Butte, Anaconda & Pacific Railway From Montana Street To South Arizona Avenue – Montana Street Adjacent Parcel, Mike Mcanulty Aug 2025

Re: Butte Priority Soils Operable Unit (Bpsou) Final Insufficiently Reclaimed Sites Field Sampling And Investigation Plan (Fsp) For Ur-19 – Butte, Anaconda & Pacific Railway From Montana Street To South Arizona Avenue – Montana Street Adjacent Parcel, Mike Mcanulty

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Identification Of Alkynyl Nicotinamide Hsn748 As A Ret Solvent-Front Mutant Inhibitor With Intracranial Efficacy, Ujjwol Khatri, Neetu Dayal, Kofi B Owusu, Mandeep Kaur Hunjan, Shriya Pandey, Haley Anne Harper, Carli Mcmahan, Bennett D Elzey, Tao Shen, Xueqing Hu, Kurt W Evans, Ahmed El-Sheikh, Seong Jun Jo, Frederick W Holtsberg, M Javad Aman, Funda Meric-Bernstam, Sukyung Woo, Herman O Sintim, Jie Wu Aug 2025

Identification Of Alkynyl Nicotinamide Hsn748 As A Ret Solvent-Front Mutant Inhibitor With Intracranial Efficacy, Ujjwol Khatri, Neetu Dayal, Kofi B Owusu, Mandeep Kaur Hunjan, Shriya Pandey, Haley Anne Harper, Carli Mcmahan, Bennett D Elzey, Tao Shen, Xueqing Hu, Kurt W Evans, Ahmed El-Sheikh, Seong Jun Jo, Frederick W Holtsberg, M Javad Aman, Funda Meric-Bernstam, Sukyung Woo, Herman O Sintim, Jie Wu

Faculty, Staff and Student Publications

RET solvent-front G810C/R/S mutations confer resistance to the currently approved RET protein tyrosine kinase inhibitors (TKIs) selpercatinib and pralsetinib. Moreover, RET fusion-positive lung adenocarcinoma frequently metastasizes to the brain. To address these challenges, it is imperative to develop a RET TKI that is effective against solvent-front mutations and exhibits intracranial activity. We synthesized alkynyl nicotinamide-based RET TKIs and tested their efficacy in cell cultures in inhibiting selpercatinib/pralsetinib-resistant RET solvent-front mutants G810C/R/S found in cancer patients, and in BaF3/KIF5B-RET(G810C) cell-derived subcutaneous and intracranial tumors in vivo. We also evaluated alkynyl nicotinamide RET TKIs in KIF5B-RET-induced lung tumors in immune competent …


Mathematics Student Teachers' Curricular Reasoning During Planning, Erika Breann Miller Aug 2025

Mathematics Student Teachers' Curricular Reasoning During Planning, Erika Breann Miller

Theses and Dissertations

Teaching is a complex practice, in part because of all the decisions teachers make daily. This is especially true for student teachers who have little to no prior teaching experience to inform them about the decisions that need to be made in the classroom and how to reason through all those decisions as they plan and enact the lessons. Secondary mathematics student teachers were introduced to the Instructional Pyramid (Dingman et al., 2021) which organizes and maps teacher’s mathematical reasoning onto four elements of a classroom—teacher, student, mathematics, and curriculum—to examine which curricular reasoning aspects they use while planning mathematics …


Quantifying Erosion Rates Of The Mission Hills Along The Calaveras, Mission, And Hayward Faults In Northern California To Better Understand The Role Of Fault Geometry On Surface Topography, Ian Duncan Lord Aug 2025

Quantifying Erosion Rates Of The Mission Hills Along The Calaveras, Mission, And Hayward Faults In Northern California To Better Understand The Role Of Fault Geometry On Surface Topography, Ian Duncan Lord

Master's Theses

The San Francisco Bay Area lacks publications on erosion rates and their relationship to restraining bend fault geometry. This thesis presents a detailed geochronologic study of erosion rates from the Mission Hills along the Calaveras, Mission, and Hayward faults located northeast of San Jose, California. The goals are to provide erosion rate values where none currently exist and to gain a better understanding of how fault geometry influences topography along restraining bends. To quantify the erosion rate of these faults, river sediments containing 10Be were collected from 14 catchments using well-established protocols. Of the successfully processed samples, the erosion rates …


A Dendrite Equivalence Relation On Loop Spaces, Spencer Arnesen Aug 2025

A Dendrite Equivalence Relation On Loop Spaces, Spencer Arnesen

Theses and Dissertations

In Definition 2.0.3 we define an equivalence relation on paths such that two paths into a space X are related if doing the first, then the second backwards factors as a loop through a dendrite. This equivalence relation induces a group structure L(X) on a large subset of the loop space of X, namely all loops that have a unique reduced representative. We show that certain continuous maps induce a homomorphism between dentropy groups and that projection from three-dimensional real space to two-dimensional real space does not induce a homomorphism on dentropy groups.. We show that dentropy groups are locally …


The Realization Of 3d Topological Spaces Branched Over Graphs, Christopher L. Duston Aug 2025

The Realization Of 3d Topological Spaces Branched Over Graphs, Christopher L. Duston

Physics Faculty Publications

In this paper we present an implementation of a computer algorithm that automatically determines the topological structure of spacetime, using a branched covering space representation. This algorithm is applied to a few simple examples in dimension 3, and a complete set of the topological spaces branched over several graphs are found. We also include some new visualizations of the branched covering construction, in order to aid and clarify the understanding of how these structures can be used in quantum gravity to realize the topological nature of the spacetime foam.