Master's thesis of Applied Physics

Brachytherapy is a form of radiotherapy in which radioactive sources are placed at short distances from, or even inside the target volume. The use of high dose rate brachytherapy is a widely accepted and clinically proven treatment for some stages of prostate cancer. The aim of this project was to investigate potential improvements on two of the most important aspects of high dose rate (HDR) and pulsed dose rate (PDR) prostate brachytherapy - prostate definition and treatment delivery verification.

121p runthenight05 01-03-2023 5 3   Download

The aim of this thesis is to ensure that accurate calibration factors are provided to radiotherapy clinics when moving to the new linac-based primary standard calibrations. Specifically, this thesis quantifies the error introduced when using a calibration factor from the ARPANSA Elekta linac on a Varian high energy platform beam at 6 MV.

102p runthenight05 01-03-2023 7 3   Download

The purpose of the study is to quantify breast dose to reassure patients and staff that these understandings still apply. A combination of measurements and simulations were used to estimate absorbed breast dose. Gafchromic® XR-QA2 film was used to measure breast dose placed inside the RANDO® phantom in a series of controlled experiments. The RANDO® is an anthropomorphic phantom commonly used for dosimetry investigations. Gafchromic® XR QA2 film is a radiochromic film that changes colour when irradiated. Simulation is commonly used and readily available.

195p runthenight05 01-03-2023 6 3   Download

The primary objectives of this study were to: Investigate the fouling potential, and characterise the organic components of the membrane foulant layers, of clarified activated sludge and lagoon effluent obtained from the WTP; Investigate the fouling propensities of EOM and AOM derived from a blue-green algal culture as it passed through the growth cycle, ie., for which the cells had not been subject to physical disruption; Determine any difference in the fouling propensity of EOM and AOM and relate it to organic composition.

99p runthenight07 01-03-2023 3 3   Download

The overall aim of this study is to determine the most effective way to reduce the radiation dose to the breast during non-breast related CT scans, whilst still maintaining a suitable image quality. This study will attempt to compare the doses and noise of various protocols that can be used for dose reduction, including tube current modulation, bismuth breast shields and manual reduction of tube current.

111p runthenight07 01-03-2023 10 3   Download

This work investigates the generation of neutron flux inside lead shielding due to cosmic rays as a function of shielding thickness by use of the GEANT Monte-Carlo modelling code. GEANT allows for the Monte-Carlo modelling of the transport of particles in matter. This includes muons, the particles of interest here, which originate from cosmic ray showers.

109p runthenight07 01-03-2023 9 3   Download

The aim of this thesis was to investigate and characterise the effect on electron dosimetry that localising different forms of bolus, both approximately tissue equivalent and non tissue equivalent, in a non conventional, although reproducible locations, (ie not on the phantom surface). A series of experiments were derived to compare the differences in beam characteristics between the recognised conventional method of locating bolus on the surface to that of bolus supported by the Low Melting point Attenuator (LMA) Electron insert.

238p runthenight07 01-03-2023 4 4   Download

The document will be structured as follows: In Chapter 2 outline the methodology, discussing the computational techniques used to evaluate the interaction energies and evaluating the construction of the TT and D3(BJ) correction terms. Chapter 3 attempts to establish a foundational understanding of how these methods model vdW interactions by evaluating the performance of the corrected and uncorrected HF and DFT methods in comparison with CCSD(T) energies for a selection of inert gas dimers, and simple molecule-molecule interactions.

63p runthenight04 02-02-2023 9 2   Download

This thesis aims to build on the current body of knowledge relating to the tertiary radiation contributions within an interventional radiology suite. An accurate estimation of tertiary radiation requires knowledge of the amount of patient-scattered radiation incident onto the concrete ceiling (the patient-scattered air kerma) and the fraction of the radiation incident on concrete that is scattered back towards the point of interest (the concrete-scattered air kerma).

125p runthenight04 02-02-2023 8 2   Download