Physics Commons^™

Development Of A Novel Technique For Predicting Tumor Response In Adaptive Radiation Therapy, Rebecca Marie Seibert

Doctoral Dissertations

This dissertation concentrates on the introduction of Predictive Adaptive Radiation Therapy (PART) as a potential method to improve cancer treatment. PART is a novel technique that utilizes volumetric image-guided radiation therapy treatment (IGRT) data to actively predict the tumor response to therapy and estimate clinical outcomes during the course of treatment. To implement PART, a patient database containing IGRT image data for 40 lesions obtained from patients who were imaged and treated with helical tomotherapy was constructed. The data was then modeled using locally weighted regression. This model predicts future tumor volumes and masses and the associated confidence intervals based …

Evaluation Of Polymer Gel Dosimeters For Measurements Of Dose And Let In Proton Beams, Kevin M. Vredevoogd

Dissertations & Theses (Open Access)

This project assessed the effectiveness of polymer gel dosimeters as tools for measuring the dose deposited by and LET of a proton beam. A total of three BANG® dosimeter formulations were evaluated: BANG®-3-Pro-2 BANGkits™ for dose measurement and two BANG®-3 variants, the LET-Baseline and LET-Meter dosimeters, for LET measurement. All dosimeters were read out using an OCT scanner. The basic characteristics of the BANGkits™ were assessed in a series of photon and electron irradiations. The dose-response relationship was found to be sigmoidal with a threshold for response of approximately 15 cGy. The active region of the dosimeter, the volume in …

Design And Optimization Of Four-Dimensional Cone-Beam Computed Tomography In Image-Guided Radiation Therapy, Moiz Ahmad

Dissertations & Theses (Open Access)

The influence of respiratory motion on patient anatomy poses a challenge to accurate radiation therapy, especially in lung cancer treatment. Modern radiation therapy planning uses models of tumor respiratory motion to account for target motion in targeting. The tumor motion model can be verified on a per-treatment session basis with four-dimensional cone-beam computed tomography (4D-CBCT), which acquires an image set of the dynamic target throughout the respiratory cycle during the therapy session. 4D-CBCT is undersampled if the scan time is too short. However, short scan time is desirable in clinical practice to reduce patient setup time. This dissertation presents the …

The Effect Of Genetic Background And Dose On Non-Targeted Effects Of Radiation, Sarah Irons, Virginia Sierra, Deborah Bowler, Kim Chapman, Stefania Militi, Fiona Lyng, Munira Kadhim

Articles

Purpose: This work investigates the hypothesis that genetic background plays a significant role in the signalling mechanisms underlying induction and perpetuation of genomic instability following radiation exposure.

Materials and methods: Bone marrow from two strains of mice (CBA and C57) were exposed to a range of X-ray doses (0, 0.01, 0.1, 1 and 3 Gy). Different cellular signalling endpoints: Apoptosis, cytokine levels and calcium flux, were evaluated at 2 h, 24 h and 7 d post-irradiation to assess immediate and delayed effects.

Results: In CBA (radiosensitive) elevated apoptosis levels were observed at 24 h post X-irradiation, and …

Development And Implementation Of The Use Of Optically Stimulated Luminescent Detectors In The Radiological Physics Center Anthropomorphic Quality Assurance Phantoms, Jennelle Bergene

Dissertations & Theses (Open Access)

The Radiological Physics Center (RPC) uses both on-site and remote reviews to credential institutions for participation in clinical trials. Anthropomorphic quality assurance (QA) phantoms are one tool the RPC uses to remotely audit institutions, which include thermoluminescent dosimeters (TLDs) and radiochromic film. The RPC desires to switch from TLD as the absolute dosimeter in the phantoms, to optically stimulated luminescent dosimeters (OSLDs), but a problem lies in the angular dependence exhibited by the OSLD. The purpose of this study was to characterize the angular dependence of OSLD and establish a correction factor if necessary, to provide accurate dosimetric measurements as …

Development And Implementation Of A Remote Audit Tool For High Dose Rate (Hdr) 192ir Brachytherapy Using Optically Stimulated Luminescence Dosimetry, Kevin Casey

Dissertations & Theses (Open Access)

This work aimed to create a mailable and OSLD-based phantom with accuracy suitable for RPC audits of HDR brachytherapy sources at institutions participating in NCI-funded cooperative clinical trials. An 8 × 8 × 10 cm³ prototype with two slots capable of holding nanoDot Al₂O₃:C OSL dosimeters (Landauer, Glenwood, IL) was designed and built. The phantom has a single channel capable of accepting all ¹⁹²Ir HDR brachytherapy sources in current clinical use in the United States. Irradiations were performed with an ¹⁹²Ir HDR source to determine correction factors for linearity with dose, dose rate, …

Radiation Dose Distributions In Three Dimensions From Tomographic Optical Density Scanning Of Polymer Gels: Ii. Optical Properties Of The Bang Polymer Gel, Yevgeniya Zastavker, Marek Maryanski, John Gore

Yevgeniya V. Zastavker

A newly developed method of radiation dosimetry makes use of the optical properties of polymer gels. The dose-response mechanism relies on the production of light-scattering polymer micro-particles in the gel at each site of radiation absorption. The scattering produces an attenuation of transmitted light intensity that is directly related to the dose and independent of dose rate. For the BANG polymer gel (bis, acrylamide, nitrogen, and gelatin) the shape of the dose-response curve depends on the fraction of the cross-linking monomer in the initial mixture and on the wavelength of light. At 500 nm the attenuation coefficient (μ) increases by …

Sensitive Fluorescence Detection Using A Camera From The Gaming Industry, Brian L. Van Hoozen Jr.

Lawrence University Honors Projects

The detection limit for fluorescence imaging has been improved by more than two orders of magnitude by a modulation technique that minimizes the influence of noise. Since most noise sources have a 1/f dependence, higher modulation frequencies result in less noise in the detected signal. Typical cameras used for imaging have frame rates of 50 or 100 hertz which is too low for substantial noise reduction. However, new time-of-flight cameras developed for the gaming industry have modulation frequencies of up to 20 MHz, allowing for a substantial reduction in noise in the detected signal. In this study, the improved detection …

Mri-Based Attenuation Correction In Emission Computed Tomography, Harry R. Marshall

Electronic Thesis and Dissertation Repository

The hybridization of magnetic resonance imaging (MRI) with positron emission tomography (PET) or single photon emission computed tomography (SPECT) enables the collection of an assortment of biological data in spatial and temporal register. However, both PET and SPECT are subject to photon attenuation, a process that degrades image quality and precludes quantification. To correct for the effects of attenuation, the spatial distribution of linear attenuation coefficients (μ-coefficients) within and about the patient must be available. Unfortunately, extracting μ-coefficients from MRI is non-trivial. In this thesis, I explore the problem of MRI-based attenuation correction (AC) in emission tomography.

In particular, I …

Verification Of The Clinical Implementation Of The Respiratory Gated Beam Delivery Technique With Synchrotron-Based Proton Irradiation, Yoshikazu Tsunashima

Dissertations & Theses (Open Access)

The clinical advantage for protons over conventional high-energy x-rays stems from their unique depth-dose distribution, which delivers essentially no dose beyond the end of range. In order to achieve it, accurate localization of the tumor volume relative to the proton beam is necessary. For cases where the tumor moves with respiration, the resultant dose distribution is sensitive to such motion. One way to reduce uncertainty caused by respiratory motion is to use gated beam delivery. The main goal of this dissertation is to evaluate the respiratory gating technique in both passive scattering and scanning delivery mode. Our hypothesis for the …

Effects Of Hyperthermia On Photochemical Internalization-Mediated Delivery Of Bleomycin, Christina Schlazer

UNLV Theses, Dissertations, Professional Papers, and Capstones

Standard treatment protocols for high-grade gliomas, such as glioblastoma multiforme (GBM), are highly ineffective due to their inability to eradicate infiltrating tumor cells. Improvements in overall survival are likely to be realized only with the development of more effective localized therapies capable of eradicating tumor cells in the surgical resection margin and beyond. Photochemical internalization (PCI) is a localized light-based therapeutic modality that enhances the efficacy of therapeutic macromolecules including chemotherapeutic agents such as bleomycin. A number of studies have shown that this photodynamic therapy (PDT) - based modality may prove effective in the treatment of high-grade gliomas.

Three-dimensional multicell …

Impaired Clearance And Enhanced Pulmonary Inflammatory/Fibrotic Response To Carbon Nanotubes In Myeloperoxidase-Deficient Mice, Aidan Meade, Anna Shvedova, Alexandr Kapralov, Wei Hong Feng, Elena Kisin, Ashley Murray, Robert Mercer, Claudette St. Croix, Megan Lang, Simon Watkins, Nagarjun Konduru, Brett Allen, Jennifer Conroy, Gregg Kotchey, Bashir Mohamed, Yuri Volkov, Alexander Star, Bengt Fadeel, Valerian Kagan

Articles

Advancement of biomedical applications of carbonaceous nanomaterials is hampered by their biopersistence and proinflammatory action in vivo. Here, we used myeloperoxidase knockout B6.129X1-MPO (MPO k/o) mice and showed that oxidation and clearance of single walled carbon nanotubes (SWCNT) from the lungs of these animals after pharyngeal aspiration was markedly less effective whereas the inflammatory response was more robust than in wild-type C57Bl/6 mice. Our results provide direct evidence for the participation of MPO – one of the key-orchestrators of inflammatory response – in the in vivo pulmonary oxidative biodegradation of SWCNT and suggest new ways to control the biopersistence of …

Advances In Ultrafast Time Resolved Fluorescence Physics For Cancer Detection In Optical Biopsy, R. R. Alfano

Publications and Research

We discuss the use of time resolved fluorescence spectroscopy to extract fundamental kinetic information on molecular species in tissues. The temporal profiles reveal the lifetime and amplitudes associated with key active molecules distinguishing the local spectral environment of tissues. The femtosecond laser pulses at 310 nm excite the tissue. The emission profile at 340 nm from tryptophan is non-exponential due to the micro-environment. The slow and fast amplitudes and lifetimes of emission profiles reveal that cancer and normal states can be distinguished. Time resolved optical methods offer a new cancer diagnostic modality for the medical community.

Assessment Of An Osteoblast-Like Cell Line As A Model For Human Primary Osteoblasts Using Raman Spectroscopy, Lindsay Mcmanus, Franck Bonnier, George Burke, Brian Meenan, Adrian Boyd, Hugh Byrne

Articles

Raman spectroscopy is employed to determine the suitability of the U20S osteoblast-like cell line for use as a model for human primary osteoblasts, with emphasis on the ability of these cell types to replicate their tissue of origin. It was found that both cell types demonstrated early stage mineral deposition that followed significantly different growth patterns. Analysis of the growth pattern and spectral data from primary cells revealed increasing bone quality ratios and a high crystallinity, consistent with previous reports. Conversely the investigation of the U20S osteoblast-like cell line provided evidence of dense multilayered mineralised regions that corresponded more closely …

Scas Officers And Council Members 2011 - 2012

Journal of the South Carolina Academy of Science

No abstract provided.

Quantitative Reagent-Free Detection Of Fibrinogen Levels In Human Blood Plasma Using Raman Spectroscopy, Kelvin Poon, Fiona Lyng, Peter Knief, Orla L. Howe, Aidan Meade, James Curtin, Hugh Byrne, Joseph Vaughan

Articles

Fibrinogen assays are commonly used as part of clinical screening tests to investigate haemorrhagic states, for detection of disseminated intravascular coagulation and as a predictor of a variety of cardiovascular events. The Clauss assay, which measures thrombin clotting time, is the most commonly used method for measuring fibrinogen levels. Nevertheless, inconsistencies are present in inter-manufacturer reagent sources, calibration standards and methodologies. Automated coagulation analysers, which measure changes in optical density during the prothrombin time (PT-Fg), have found use in many hospitals. However, the PT-Fg method is found to give falsely elevated values due to varying choices of calibrants, reagents and …

Capturing Motion, Allison Marsh

Section 3: Imaging the Fast Moving

No abstract provided.

Understanding Fracture, Allison Marsh

Section 3: Imaging the Fast Moving

No abstract provided.

Listen, Allison Marsh

Section 3: Imaging the Fast Moving

No abstract provided.

Photographic Evidence, Allison Marsh

Section 3: Imaging the Fast Moving

No abstract provided.

Spotlight On Usc: Mechanical Engineering, Allison Marsh

Section 3: Imaging the Fast Moving

No abstract provided.

Influencing Art, Allison Marsh

Section 3: Imaging the Fast Moving

No abstract provided.

The Effect Of Participating In Continuing Optometric Education: A Pilot Study, Claire E. Mcdonnell, Martina Crehan

Other

Purpose: To determine whether participation in two different post graduate optometry workshops resulted in a change in practice for the participants, in their subsequent practice.

Methods: 38 optometrists, who had attended a continuing professional development (CPD) workshop on punctal plugs and lacrimal syringing, were surveyed by email and telephone, between four and thirteen months post workshop, to ascertain if they had made a change to their practice. A second group of 32 optometrists, who had attended a continuing education and training (CET) workshop on binocular vision, were surveyed by email, telephone and postal mail between six and nine months post …

Analysis Of Human Skin Tissue By Raman Microspectroscopy: Dealing With The Background, Franck Bonnier, Syed Mehmood Ali, Peter Knief, Helen Lambkin, Kathleen Flynn, Vincent Mcdonagh, Claragh Healy, Thomas Lee, Fiona Lyng, Hugh Byrne

Articles

Raman microspectroscopy is widely used for molecular characterisation of tissue samples. Nevertheless, when working in vitro on tissue sections, the presence of a broad background to the spectra remains problematic and its removal requires advanced methods for pre-processing of the data. To date, research efforts have been primarily devoted to development of techniques of statistical analysis to extract the relevant information contained in the spectra. However, few attempts have been made to understand the origin of the background and to improve the protocols used for the collection of Raman spectra that could lead to the reduction or elimination of the …

Microfluidic Impedance Spectroscopy As A Tool For Quantitative Biology And Biotechnology, Ahmet C. Sabuncu, Jie Zhuang, Juergen F. Kolb, Ali Beskok

Mechanical & Aerospace Engineering Faculty Publications

A microfluidic device that is able to perform dielectric spectroscopy is developed. The device consists of a measurement chamber that is 250 μm thick and 750 μm radius. Around 1000 cells fit inside the chamber assuming average quantities for cell radius and volume fraction. This number is about 1000 folds lower than the capacity of conventional fixtures. A T-cell leukemia cell line Jurkat is tested using the microfluidic device. Measurements of deionized water and salt solutions are utilized to determine parasitic effects and geometric capacitance of the device. Physical models, including Maxwell-Wagner mixture and double shell models, are used to …

Table Of Contents

Journal of the South Carolina Academy of Science

No abstract provided.

Development And Implementation Of Acoustic Feedback Control For Scanning Probe Microscopy, Rodolfo Fernandez Rodriguez

Dissertations and Theses

A remote-sensing acoustic method for implementing position control feedback in Scanning Probe Microscopy (SPM) is presented. The capabilities of this feedback control using the new Whispering Gallery Acoustic Sensing (WGAS) method is demonstrated in a Shear-force Scanning Probe Microscope that uses a sharp probe attached to a piezoelectric Quartz Tuning Fork (QTF) firmly mounted on the microscope's frame. As the QTF is electrically driven its mechanical response reaches the SPM frame which then acts as a resonant cavity producing acoustic modes measured with an acoustic sensor strategically placed on the SPM head. The novelty of the WGAS resides in using …

Thermosensitive Magnetic Nanoparticles For Self-Controlled Hyperthermia Cancer Treatment, Karen S. Martirosyan

Physics and Astronomy Faculty Publications and Presentations

Magnetic nanoparticles show remarkable phenomena such as superparamagnetism, high field irreversibility and high saturation magnetization [1]. The study of magnetic nanoparticles has been a very active research field due to many important applications such as drug delivery, imaging and hyperthermia cancer treatment [2]. Hyperthermia has been used for many years to treat a wide variety of tumors in patients and used as well as an adjunct to cancer radiotherapy or chemotherapy [3,4]. Its use is based on the fact that tumor cells are more sensitive to temperature in the range of 42–45°C (which yields necrosis, coagulation, or carbonization) than normal …

Volume 04, Matt Szemborski, Phillip Van Ness, Sarah Croughwell, Sarah Mayfield, Alyssa Strackbein, Marley Kimmel, Stephanie Skipp, Jamie Yurasits, Katherine Taggart, Alex Leonhart, Kristen Rawls, Andrew Armes, Amanda Haymens, Allison Paqlowski, Erica May, Stephanie Lane, Luke Acree, Cassandra L. Wilson, Stephanie Pishock, Erica Hopson, K. Juston Osborne, Katheryn Grayson, Kyle Fowlkes, Jessica Cox, Kaity Byrum, John-Harwood Scott, Ashley Johnson, Samantha Hockman, Emily Staskiel, Nancy Macdonald, R. Kruger Bressin, Benjamin P. Bilodeau, Andrea Irby, Kristin Macquarrie, Sarah Bietsch, Elizabeth Bednar

Incite: The Journal of Undergraduate Scholarship

Please note that part of pages 92-95 are redacted, in the digital copy, due to a misprint of the original printed article.

Introduction from Dean Dr. Charles Ross

The Internal Other: Transculturation and Postcolonial Magical Realism in Rushdie’s Midnight’s Children by Matt Szemborski

Photography by Phillip Van Ness

Photography “Waterfall” by Sarah Croughwell

Romancing the Bite: Statistical Analysis of Young Adult Vampire Novels by Sarah Mayfield

Photography by Alyssa Strackbein

Photography by Marley Kimmel

Wine and Society in the Viceroyalty of Peru by Stephanie Skipp

Analysis of Claud Monet’s Impression, Sunrise by Jamie Yurasits

Exploring Meaning: The Lindisfarne Gospels by …