A5075964482- Advanced Radiotherapy Techniques
- Radiation Therapy and Dosimetry
- Medical Imaging Techniques and Applications
- Radiation Dose and Imaging
- Particle physics theoretical and experimental studies
- Nuclear physics research studies
- Particle Detector Development and Performance
- Digital Radiography and Breast Imaging
- Particle Accelerators and Free-Electron Lasers
- Quantum Chromodynamics and Particle Interactions
- Advanced X-ray and CT Imaging
- Astronomical and nuclear sciences
- Advanced Thermodynamic Systems and Engines
- Nuclear Physics and Applications
- Refrigeration and Air Conditioning Technologies
- Radiation Effects and Dosimetry
- Radiation Detection and Scintillator Technologies
- Atomic and Molecular Physics
- High-Energy Particle Collisions Research
- Particle accelerators and beam dynamics
- Electric and Hybrid Vehicle Technologies
- Non-Invasive Vital Sign Monitoring
- Advanced Chemical Physics Studies
- Radioactive contamination and transfer
- Radioactivity and Radon Measurements
University of North Carolina at Chapel Hill
2004-2024
Thomas Jefferson National Accelerator Facility
2020-2023
Old Dominion University
2020-2022
Argonne National Laboratory
2020
Medical Research Associates
2012-2017
Hagerstown Community College
2012-2014
Duke Medical Center
2010-2013
Augusta University
2013
Duke University
2010-2013
University of Hawaii Cancer Center
2013
We describe offline event reconstruction for the CEBAF Large Acceptance Spectrometer at 12 GeV (CLAS12), including an overview of framework and software tools, a description algorithms developed individual detector subsystems, overall approach charged neutral particle identification. also present scheme data processing code management procedures.
The $^{17}\mathrm{O}(p,\ensuremath{\gamma})^{18}\mathrm{F}$ and $^{17}\mathrm{O}(p,\ensuremath{\alpha})^{14}\mathrm{N}$ reactions have a profound influence on hydrogen-burning nucleosynthesis in number of stellar sites, including red giants, asymptotic giant branch (AGB) stars, massive classical novae. Previously evaluated thermonuclear rates for both carry large uncertainties. We investigated the proton-capture reaction $^{17}\mathrm{O}$ bombarding energy range...
There is significant interest in delivering precisely targeted small-volume radiation treatments, the pre-clinical setting, to study dose–volume relationships with tumour control and normal tissue damage. For these studies it vital that image guidance systems target positioning are accurately aligned (IGRT), order deliver dose according treatment plan. In this work we investigate IGRT targeting accuracy of X-RAD 225 Cx system from Precision X-Ray using high-resolution 3D dosimetry...
We report on the observation of a new resonance at E(lab)(R)=190 keV in 17O(p,gamma)18F reaction. The measured strength amounts to omegagamma(pgamma)=(1.2+/-0.2)x10(-6) eV. With this value, uncertainties and 17O(p,alpha)14N thermonuclear reaction rates are reduced by orders magnitude nova temperatures. Our significantly improved have major implications for galactic synthesis 17O, stellar production radioisotope 18F, predicted oxygen isotopic ratios ejecta.
PRESAGE® is a solid radiochromic dosimeter consisting of polyurethane matrix, triarylmethane leuco dye, and trihalomethane initiator. Varying the composition and/or relative amounts these constituents can affect dose sensitivity, post-irradiation stability, physical properties dosimeter. This allows customisation to meet application-specific requirements, such as low sensitivity for high applications, stability remote dosimetry, optical clearing reusability, tissue-like elasticity deformable...
A midsized broad beam Optical-CT scanner is being developed for collaborative research between Duke and the Radiological Physics Center (RPC). The Midsized Scanner (DMOS-RPC) designed to be compatible with several of RPC phantoms, including head neck, stereotactic SRS, lung phantoms. Preliminary data investigating basic performance described. Two 10 cm PRESAGE cylinders were irradiated simple test plans. Projections ~80 μm resolution each dosimeter collected at 1 degree intervals over a full...
Beam-recoil transferred polarizations for the exclusive electroproduction of ${K}^{+}\mathrm{\ensuremath{\Lambda}}$ and ${K}^{+}{\mathrm{\ensuremath{\Sigma}}}^{0}$ final states from an unpolarized proton target have been measured using CLAS12 spectrometer at Jefferson Laboratory. The measurements beam energies 6.535 7.546 GeV span range four-momentum transfer ${Q}^{2}$ 0.3 to 4.5 ${\mathrm{GeV}}^{2}$ invariant energy $W$ 1.6 2.4 GeV, while covering full center-of-mass angular ${K}^{+}$....
Achieving adequate verification and quality-assurance (QA) for radiosurgery treatment of trigeminal-neuralgia (TGN) is particularly challenging because the combination very small fields, high doses, complex irradiation geometries (multiple gantry couch combinations). TGN treatments have extreme requirements dosimetry tools QA techniques, to ensure verification. In this work we evaluate potential Presage/Optical-CT system as a tool distributions in high-resolution 3D. A was planned delivered...
Deformable 3D dosimeters have potential applications in validating deformable dose mapping algorithms. This study evaluates a novel PRESAGE® dosimeter and its application toward the algorithm employed by VelocityAI. The exhibited linear response with sensitivity of 0.0032 ΔOD/(Gy/cm). Comparison an experimental irradiated MLC pencilbeam checkerboard pattern under lateral compression up to 27% non-deformed control same verified tracking deformation. CTs prior during were exported into...
We describe a method to directly measure the radial dose and anisotropy functions of brachytherapy sources using polyurethane based dosimeters read out with optical CT. measured for Cs-137 source PRESAGE® dosimeter (9.5cm diameter, 9.2cm height) 0.35cm channel drilled placement. The was immersed in water irradiated 5.3Gy at 1cm. Pre- post-irradiation CT scans were acquired Duke Large field view Optical Scanner (DLOS) reconstructed 0.5mm isotropic voxel size. factor matched published fit...
Purpose: Small field dosimetry is challenging that impacts patient specific QA in proton beam therapy due to detector size, aperture scattering and disequilibrium. Therefore, it urgent develop an accurate efficient method quantify the uncertainty of 3D small fields. This study investigated feasibility using a new formula PRESAGE® for irregular therapy. Methods: Three cylindrical shape dosimeters (10 cm or 4 diameter, 6 length) (C304H510N20O71SBr) were irradiated with three fields (field size...
Pneumonia is the leading cause of death globally in children aged 0-5 years. Early access to pulse-oximetry and supplemental oxygen low-resource, pre-hospital settings may result improved pediatric pneumonia outcomes. However, few data exist regarding their application such settings. We performed an exploratory cost-effectiveness analysis using a decision model examine use Our yielded Incremental Cost-Effectiveness Ratio (ICER) for $229 (USD) per life-year (LY) saved compared no use. Given...
Stereotactic radiosurgery has become a widely used technique to treat solid tumors and secondary metastases of the brain. Multiple targets can be simultaneously treated with single isocenter in order reduce set-up time improve patient comfort workflow. In this study, 5-arc multifocal RapidArc treatment was delivered multiple PRESAGE® dosimeters explore repeatability treatment. The three delivery measurements agreed well each other, less than 3% standard deviation dose target. deliveries also...
Purpose: To commission and benchmark a 3D dosimetry system for clinical use, in particular, verification commissioning of complex radiation treatments like VMAT, IMRT gated treatments. The is composed two parts: radiochromic plastic dosimeter Presage, which responds to absorbed dose with linear change optical‐density; the Duke Large field view Optical‐CT Scanner (DLOS). Methods: DLOS involved creating stray light spectral corrections, determining dynamic range, spatial resolution, noise,...
New results for the exclusive and quasifree cross sections off neutrons bound in deuterium ${\ensuremath{\gamma}}_{v}n(p)\ensuremath{\rightarrow}p{\ensuremath{\pi}}^{\ensuremath{-}}(p)$ are presented over a wide final state hadron angle range with kinematic coverage of invariant mass ($W$) up to 1.825 GeV four-momentum transfer squared (${Q}^{2}$) from 0.4 1.0 ${\mathrm{GeV}}^{2}$. The structure functions were extracted their Legendre moments obtained. Final-state-interaction contributions...
Three-dimensional dose distributions from liquid brachytherapy were measured using PRESAGE(®) dosimeters. The dosimeters exposed to Y-90 for 5.75 days and read by optical tomography. are consistent with estimates beta kernels.
Purpose: The recent emergence of powerful, fast and high‐resolution 3D dosimetry techniques brings exciting potential to radically strengthen the foundations quality‐assurance in radiation therapy, hence treatment efficacy. This work presents a new acquisition method for by optical‐computed‐tomography (optical‐CT), which can improve accuracy when imaging strongly attenuating dosimeters (e.g. large or heavily dosed). Methods: involves acquiring optical‐CT projection images where intensity...
Purpose: To commission and characterize a novel small animal irradiator, the XRad225cx from Precision X‐Ray Inc. This system is capable of delivering both square circular fields ranging in size 1mm to 40mm. The combination very field relatively low energy (225kV) represents substantial challenge acquiring accurate dosimetry beam data. work reports on commissioning studies using 2 independent systems: EBT2 radiochromic film PRESAGETM /optical‐CT 3D dosimetry. Methods: Initial measurements...
There is significant interest in delivering precisely targeted small-volume radiation treatments, the pre-clinical setting, to study dose-volume relationships with tumor control and normal tissue damage. In this work we investigate IGRT targeting accuracy of XRad225Cx system from Precision x-Ray using high resolution 3D dosimetry techniques. Initial results revealed a error about 2.4mm. This was reduced within 0.5mm after hardware software had been recalibrated. The facility for essential...
To evaluate and investigate the feasibility of a new method for validating dose tracking algorithms in deforming tissues using novel deformable 3D dosimeter.A Presage dosimeter is reported consisting stretchy polyurethane matrix doped with radiochromic leuco-dye. Two cylindrical dosimeters (6 cm diameter, 5 long) were manufactured irradiated checkerboard arrangement mm square pencil beams created by MLC fields. One was under lateral compression 33% down to 4 diameter) simulate deformed...
Volumetric modulated arc therapy (VMAT) enables stereotactic radiosurgery (SRS) treatment for multiple lesions with a single isocenter setup. Dosimetry verification is highly challenging however, and the purpose of this study to validate new using novel 3D dosimetry techniques, potential dramatically more comprehensive than possible conventional approaches.A cylindrical PRESAGE dosimeter was inserted into an RPC type head phantom validation. The immobilized SRS U-frame system set simulation...