Optimizing Palliative Spine Radiation: A Dosimetric Comparison Of Hybrid Arc Therapy And Conventional Appa Techniques,
2025
Grand Valley State University
Optimizing Palliative Spine Radiation: A Dosimetric Comparison Of Hybrid Arc Therapy And Conventional Appa Techniques, Alaina Vaneaton
Masters Projects
This study aimed to evaluate the dosimetric impact of Hybrid Arc Palliative Radiation Therapy (HART) versus conventional anterior-posterior/posterior-anterior (APPA) beam arrangements for thoracic spine metastases. The primary objective was to assess differences in conformity, homogeneity, and organ-at-risk (OAR) sparing between the two techniques. A retrospective plan comparison was conducted using anonymized datasets from twenty patients previously treated with HART. Each case was replanned using a standard APPA technique, normalized to match the target coverage of the original HART plan within 0.1%. All plans were prescribed 20 Gy in 5 fractions. Plan quality was evaluated using conformity index (CI), homogeneity index …
Comparison Of Finite-Amplitude Acoustic Models: Single Equation Of Motion For Potential Vs System-Level Approaches,
2025
University of New Orleans
Comparison Of Finite-Amplitude Acoustic Models: Single Equation Of Motion For Potential Vs System-Level Approaches, Mohammad Javad Mohaghegh Kojidi
LSU New Orleans Theses and Dissertations
This study evaluates two finite-amplitude acoustic models, by solving the associated equations of motion (in potential form), and then compares the results with recent studies using hyperbolic system-level approaches. An implicit numerical method is employed to solve the second-order equations in one dimension. The performances of the Diaz et al. (2018) and Blackstock (1963) models in approximating the acoustic special case of the Euler system, via velocity profile plots and related metrics, are evaluated and compared. Working in the setting of the classical signaling problem with sinusoidal input, present results (using the single equation of motion approach) provide independent confirmation …
Investigating Global Lightning Observed From Ground And Space, And Its Relationship To Solar Activity,
2025
Florida Institute of Technology
Investigating Global Lightning Observed From Ground And Space, And Its Relationship To Solar Activity, Megan Diane Mark
Theses and Dissertations
The extremes of lightning, specifically lightning with long-lasting continuing currents and lightning with extremely high peak currents, are investigated from both ground- and space-based observations. Additionally, the potential solar influence on lightning is investigated on large spatial scales.
Continuing currents may occur following the impulsive flow of current during a cloud-to-ground (CG) return stroke and are usually low amplitude (from a few amperes to a few kiloamperes) and long duration (several to hundreds of milliseconds). Remotely estimating their duration from the electromagnetic fields measured by existing ground-based lightning locating systems (LLSs) is not possible, but some space-based lightning detection systems …
Insights Into The Radiation Chemistry Of Flash Radiation Therapy,
2025
The University of Texas MD Anderson Cancer Center
Insights Into The Radiation Chemistry Of Flash Radiation Therapy, Alan E. Lopez Hernandez
Dissertations and Theses (Open Access)
Purpose: FLASH radiation therapy (FLASH-RT) is an emerging modality that delivers radiation at ultra-high dose rates (UHDR) and has shown consistent normal tissue sparing while preserving tumor control compared to conventional RT—a phenomenon termed the FLASH effect. Despite promising results, the mechanisms behind the FLASH effect remain unclear. Many hypotheses point to radiolytic interactions, but experimental validation is limited. This work aims to develop a robust experimental platform to evaluate the relationship between radiolytic species production and physical beam parameters relevant to FLASH-RT, alongside dosimetry tools for reliable UHDR beam characterization.
Methods: A beam collector (BC) Faraday cup detector was …
Quantum Dot Light Emitting Diodes As A Light Source For Photodynamic Therapy,
2025
University of Massachusetts Boston
Quantum Dot Light Emitting Diodes As A Light Source For Photodynamic Therapy, Hamid El Hamidi
Graduate Doctoral Dissertations
ABSTRACT:
QUANTUM DOT LIGHT EMITTING DIODES AS A LIGHT SOURCE FOR PHOTODYNAMIC THERAPY
Photodynamic therapy is a cancer treatment modality that involves the accumulation of a photosensitizer, exposure to visible light, and the presence of oxygen, resulting in the formation of highly reactive and cytotoxic singlet oxygen. PDT has been shown to be more effective as the fluence rate decreases due to oxygen availability and the absence of photobleaching. On the other hand, Quantum Dot Light Emitting Diodes QLEDs- a new form of light source based on nanoparticles (quantum dots)- emerge as a potentially advantageous light source for certain types …
Dose Characterization Of Galactic Cosmic Rays In The Human Brain: A Phits-Based Study With A Segmented Anatomical Phantom,
2025
Louisiana State University and Agricultural and Mechanical College
Dose Characterization Of Galactic Cosmic Rays In The Human Brain: A Phits-Based Study With A Segmented Anatomical Phantom, Shanice N. Manning
LSU Master's Theses
Astronauts aboard the International Space Station (ISS) are chronically exposed to a complex space radiation environment composed of galactic cosmic rays (GCR), solar particles, and Earth's trapped radiation. These high-energy particles interact with spacecraft shielding, producing secondary particles that can penetrate inside and deposit energy in sensitive tissues. Although animal studies have been useful in assessing space radiation risks, anatomical and physiological differences limit their applicability to human anatomy especially neuroanatomy. To address this gap, we developed a computational framework to model radiation dose distribution within the human brain using Monte Carlo simulations in Particle and Heavy Ion Transport code …
The Limits Of Knowing: Determinism, Uncertainty, And What’S Beyond The Human Gaze,
2025
Rhode Island School of Design
The Limits Of Knowing: Determinism, Uncertainty, And What’S Beyond The Human Gaze, Xilong T. Zhang
Masters Theses
This essay traces a personal philosophical and artistic journey from rigid belief in scientific determinism to an evolving embrace of uncertainty, subjectivity, and computational perception. Raised in an atheist, scientifically grounded household in China, the author initially adopted Newtonian determinism and Laplace’s thought experiment of a fully predictable universe as guiding principles. These beliefs informed early artistic practices rooted in Constructivism, geometry, and rule-based aesthetics. However, a failed attempt to fully optimize life through deterministic control led to physical and mental collapse, prompting deeper exploration into Cartesian dualism, quantum mechanics, and the limits of reason. Through Heisenberg’s Uncertainty Principle and …
Examining The Accuracy Of The Omni Data In Representing Geomagnetic Storm Observations Near Earth And The Effect On Global Modeling,
2025
University of Texas at Arlington
Examining The Accuracy Of The Omni Data In Representing Geomagnetic Storm Observations Near Earth And The Effect On Global Modeling, James T. Davis
2025 Spring Honors Capstone Projects - Archive
The accuracy of OMNI dataset being propagated to bow shock nose and used to represent geomagnetic storms is a known issue. Inaccuracies of this data bring erroneous results in scientific endeavors therefore establishing the importance of accuracy and consistency. This case study examines the accuracy of the OMNI data and data near-Earth in representing geomagnetic storms with different drivers on global simulations. This research will include examples of global magnetosphere simulations, such as SWMF, driven with two storms driven by coronal mass ejections, and one driven by a high-speed stream using OMNI data and data near-Earth to illustrate potential variations …
The Mechanics Of Angular Momentum Generation In Discus Throwing,
2025
Fort Hays State University
The Mechanics Of Angular Momentum Generation In Discus Throwing, Andreas Maheras
Track and Field Faculty Publications
Angular momentum development in the back of the ring, during the first double and first single support, is of paramount importance in discus throwing because this is where almost all the angular momentum the thrower can generate will be generated. From a purely mechanical point of view, to achieve that, the thrower should keep her arms spread apart, and also actively throw both the right leg and the left arm and shoulders CCW. Those actions will collectively contribute in slowing down the lower body, as the thrower actively chooses to pass as much angular momentum to the upper body at …
The Search For Slow Particles And Magnetic Monopoles With Nova,
2025
University of South Alabama
The Search For Slow Particles And Magnetic Monopoles With Nova, John Clark
Poster Presentations
Singular magnetic poles, north or south, have been theorized to exist for hundreds of years. In the modern day, the elusive singular magnetic pole still remains undiscovered. The appearance of this particle would help confirm many Grand Unified Theories, GUTs, and revolutionize our understanding of some of the fundamental forces of the universe. Fermilab's NOvA collaboration is working on ways to screen and detect magnetic monopoles and other slow-moving particles coming from outer space alongside their main mission to study neutrinos. The aim of this work is to determine and improve the Far Detector’s efficiency at identifying slow moving particles. …
Geometric Algebra For Field Theory In Curved Spacetime,
2025
Utah State University
Geometric Algebra For Field Theory In Curved Spacetime, Kevin Rhine
All Graduate Reports and Creative Projects, Fall 2023 to Present
Physics seeks to understand the universe by uncovering the fundamental laws that govern matter, energy, space, and time. At its heart lies the challenge of unification: finding a mathematical framework that consistently describes these interactions across all scales, from the subatomic to the cosmological.
This thesis explores geometric algebra, a mathematical language that unifies algebra and geometry, as a tool for advancing this understanding. By extending this framework to curved spacetimes, where gravity influences the structure of space and time, we investigate its ability to describe physical phenomena such as electromagnetism and general relativity. A notable contribution includes the geometric …
Signal Modeling Of High Purity Germanium Detectors,
2025
University of Connecticut - Storrs
Signal Modeling Of High Purity Germanium Detectors, Brooke Parker Thibodeau
Honors Scholar Theses
Pulse shape analysis can be used to analyze radiation incident on a semiconductor diode detector. Finite element analysis (FEA) can be used to simulate high purity germanium detectors with user-specified geometry, impurity concentration, and bias voltage. Subsequent streamline calculation can be used to conduct pulse shape analysis for single and multiple site gamma-ray interactions within the detector volume. Cross sections of the detector can be visualized by contour plots of the electric field, drift velocity magnitude, and collection time, as well as t30 and t90 rise-time values.
Revealing Hidden Histories: A Multi-Sensor Aerial Survey For Detecting Unmarked Burials At Sinking Spring Cemetery, Abingdon, Va,
2025
East Tennessee State University
Revealing Hidden Histories: A Multi-Sensor Aerial Survey For Detecting Unmarked Burials At Sinking Spring Cemetery, Abingdon, Va, Noah Hall
Electronic Theses and Dissertations
The Sinking Spring Cemetery, established in 1773 in Abingdon, Virginia, spans 11 acres and is divided by a road. The 9-acre southern section was reserved for white church members. Enslaved individuals and free people of color were buried in the smaller northern section, where few headstones remain today. This study aimed to map the unmarked graves using thermal, multispectral, and Light Detection and Ranging (LiDAR) sensors deployed on unmanned aerial systems. Graves were characterized by subtle topographic depressions mapped by LiDAR and cooler radiant temperature anomalies in thermal imagery. Thermal data collected at different times of the day and year …
Automated Radiotherapy Treatment Planning For Breast Cancer: A Robust To Ol For Global Deployment,
2025
The Texas Medical Center Library
Automated Radiotherapy Treatment Planning For Breast Cancer: A Robust To Ol For Global Deployment, Hana Baroudi
Dissertations and Theses (Open Access)
Breast cancer incidence continues to rise worldwide, particularly in low- and middle-income countries, where limitations in resources already constrain access to timely care. Radiotherapy is a cornerstone of breast cancer management, proven to significantly lower both recurrence and mortality. However, a growing shortage of radiation staff worldwide threatens the prompt delivery of these treatments.This thesis proposes an automated solution to address the limited accessibility of radiotherapy planning in breast cancer management by developing an end-to-end automated treatment planning model and evaluating its performance and limitations across diverse patient populations.
An automated contouring model was trained using data from 104 whole-breast …
Development Of Lineal Energy Spectrum-Based Biological Effects Models For Protons,
2025
University of Texas M.D. Anderson Cancer Center
Development Of Lineal Energy Spectrum-Based Biological Effects Models For Protons, Joseph M. Decunha, Fada Guan, David Grosshans, Zhongxing Liao, Dragan Mirkovic, Oleg Vassiliev, Radhe Mohan
Dissertations and Theses (Open Access)
In this dissertation, methods are developed and described to allow for the rapid calculation of microdosimetric spectra (specifically, lineal energy) for protons. SuperTrack, a GPU-accelerated tool for calculation of microdosimetric spectra was developed and is capable of computing lineal energy spectra up to 5000x faster than using Geant4 directly. Proton lineal energy spectra generated by SuperTrack are indistinguishable from those generated by Geant4. With SuperTrack, large libraries of lineal energy spectra for monoenergetic protons spanning 0-300 MeV have been developed. The proton lineal energy spectra calculated by SuperTrack have been compared to experimental measurements made by a tissue equivalent proportional …
The Role Of The Neutral Wind In Observations Of High-Latitude Ionospheric Energy Transfer,
2025
Clemson University
The Role Of The Neutral Wind In Observations Of High-Latitude Ionospheric Energy Transfer, Andrew M. Pepper
All Dissertations
Joule heating results from the collisional interaction between ions and neutrals and serves as a crucial mechanism for energy transfer between Earth's magnetosphere and ionosphere-thermosphere system, particularly at high latitudes. This dissertation investigates the modulation of Joule heating by altitude-resolved neutral winds, electric fields, and conductivity variations through multi-instrument observational analysis and modeling that incorporates both in-situ and ground-based sources to measure the main drivers of ion-neutral coupling. The observations presented consistently demonstrate a dual regulatory effect of the neutral wind on energy deposition that varies systematically with both geomagnetic activity level and proximity to auroral boundaries. In regions characterized …
An Analysis On The Time Effectiveness Of Speeding While Driving A Vehicle,
2025
Arkansas Tech University
An Analysis On The Time Effectiveness Of Speeding While Driving A Vehicle, Joy Skaggs
ATU Scholars Symposium
Speeding is responsible for roughly a third of all crashes, often coming at a deadly cost. The National Highway Traffic Safety Administration reports many negative consequences, such as a greater likelihood of loss of vehicle control, reduced protection equipment effectiveness, increased stopping distance, crash severity, and fuel consumption (National Highway Traffic Safety Administration, n.d.). Yet despite these costs, drivers continue to speed. In fact, in our fast paced world, speeding is so normalized that it’s uncommon to encounter a driver following the speed limit. Hawaiian psychology professor Leon James explains it best: people have twisted their definitions of speeding to …
Charging And Discharging Capacitors: Brightspace Package Of An Arithmetic Quiz,
2025
Borough of Manhattan Community College CUNY
Charging And Discharging Capacitors: Brightspace Package Of An Arithmetic Quiz, Vasiliy Znamenskiy
Open Educational Resources
Description:
This material is a quiz in the Brightspace Learning Management System (LMS). The quiz includes 10 physics problems on the topic of charging and discharging capacitors through a resistor.
The quiz assesses student understanding of key concepts, including voltage and charge of a capacitor, exponential functions, time constants, and dynamic changes in voltage and current.
Quiz problems are called in Brightspace LMS as arithmetic questions. The Problems give students random initial values to provide many quiz variants.
The quiz is appropriate for high school AP Physics or introductory college-level physics courses.
Key Features:
10-question quiz in Brightspace importable format …
Understanding Flow: An Experimental Analysis Of A Magnetohydrodynamic Fluid Pump,
2025
Loyola Marymount University
Understanding Flow: An Experimental Analysis Of A Magnetohydrodynamic Fluid Pump, Quintin Yates, Emily Hawkins
Honors Thesis
When a magnetic field and electrical current are perpendicular to each other, an ionized fluid will experience a force called the Lorentz force. This force can be applied to create a pump. These pumps have potential applications in desalination and fluid systems in space. The technology is new, and still not well understood but are a potential alternative to typical mechanical pumps. This thesis develops a comprehensive experimental understanding of the fluid flow through a 3D-printed magnetohydrodynamic (MHD) pump. Lagrangian particle tracking (LPT) uses neutrally buoyant particles and a camera system to collect quantitative velocity information of a system. Particle …
Heavy Metals In Healthy Water Samples Used By Newborn In Al-Najaf Governorate, Iraq,
2025
Department of Physics, Faculty of Science, University of Kufa, Al-Najaf, Iraq
Heavy Metals In Healthy Water Samples Used By Newborn In Al-Najaf Governorate, Iraq, Ban Hussein Ali, Ali Abid Abojassim
Al-Bahir
Water is essential for life, so monitoring water quality is important. This research focuses on measuring heavy metals (Lead, Pb; Cadmium, Cd; Chromium, Cr (in 14 healthy water samples of two types; bottled water and filtered water used by newborn children in Al-Najaf governorate, Iraq. Atomic absorption spectroscopy (AA-7000, Japan) was used to conduct the experimental analysis. Also, health risks parameters (non-carcinogenic and carcinogenic) due to Pd, Cd, and Cr concentrations were calculated. The results of Pb, Cd, and Cr concentrations in mg/L for bottled water samples were ranged 0.03-0.83, 0.01-0.69, and 0.01-0.76, respectively, while the range values for filter …
