Developing a Virtual Interdisciplinary Research Community in Clinical Education: Enticing People to the “Tea-Room”

Background: Many interdisciplinary collaborative research programs in the health sector are adopting the community of practice concept within virtual environments. This study explores the factors that affect the members of a geographically dispersed group of health professionals in their attempt to create an interprofessional Virtual Community of Practice (VCoP) from which to promote clinical education research.Method & Findings: A survey was used to determine participants’ degree of computer competency. System logs recorded members’ access details and site activity. Member perceptions and beliefs were established using focus groups. While members stated they were enthusiastic about the VCoP, the primary use was viewing. Their online behaviour indicated that on average it took six visits to generate a post. This suggests a stronger focus on viewing (consumption of) information than on contributing (construction of) information.Conclusions: We believe it is crucial for members to contribute during the initial phase of any pre-structured VCoP in order to overcome the consumption-construction dilemma. It is during this initial phase that members will decide on the community’s value. If the community cannot offer added value, members who engage are likely to consume for a time and then leave

Optimization of extracranial stereotactic radiation therapy of small lung lesions using accurate dose calculation algorithms

BACKGROUND: The aim of this study was to compare and to validate different dose calculation algorithms for the use in radiation therapy of small lung lesions and to optimize the treatment planning using accurate dose calculation algorithms. METHODS: A 9-field conformal treatment plan was generated on an inhomogeneous phantom with lung mimics and a soft tissue equivalent insert, mimicking a lung tumor. The dose distribution was calculated with the Pencil Beam and Collapsed Cone algorithms implemented in Masterplan (Nucletron) and the Monte Carlo system XVMC and validated using Gafchromic EBT films. Differences in dose distribution were evaluated. The plans were then optimized by adding segments to the outer shell of the target in order to increase the dose near the interface to the lung. RESULTS: The Pencil Beam algorithm overestimated the dose by up to 15% compared to the measurements. Collapsed Cone and Monte Carlo predicted the dose more accurately with a maximum difference of -8% and -3% respectively compared to the film. Plan optimization by adding small segments to the peripheral parts of the target, creating a 2-step fluence modulation, allowed to increase target coverage and homogeneity as compared to the uncorrected 9 field plan. CONCLUSION: The use of forward 2-step fluence modulation in radiotherapy of small lung lesions allows the improvement of tumor coverage and dose homogeneity as compared to non-modulated treatment plans and may thus help to increase the local tumor control probability. While the Collapsed Cone algorithm is closer to measurements than the Pencil Beam algorithm, both algorithms are limited at tissue/lung interfaces, leaving Monte-Carlo the most accurate algorithm for dose prediction

Національно-демократичні об'єднання та політичні партії в Україні кінця XIX - початку XX століття

Deep brain stimulation (DBS) has become increasingly important for the treatment and relief of neurological disorders such as Parkinson's disease, tremor, dystonia and psychiatric illness. As DBS implantations and any other stereotactic and functional surgical procedure require accurate, precise and safe targeting of the brain structure, the technical aids for preoperative planning, intervention and postoperative follow-up have become increasingly important. The aim of this paper was to give and overview, from a biomedical engineering perspective, of a typical implantation procedure and current supporting techniques. Furthermore, emerging technical aids not yet clinically established are presented. This includes the state-of-the-art of neuroimaging and navigation, patient-specific simulation of DBS electric field, optical methods for intracerebral guidance, movement pattern analysis, intraoperative data visualisation and trends related to new stimulation devices. As DBS surgery already today is an important technology intensive domain, an "intuitive visualisation" interface for improving management of these data in relation to surgery is suggested

Medical radiation dosimetry higher doctoral degree thesis

I am a graduate of the University of Wollongong for both my undergraduate and postgraduate degrees, BSc(Hons) (1992) and PhD (1998). Also since 1996 until present I have held the position of honorary fellow, honorary senior fellow and honorary principal fellow through the Department of Engineering Physics (Previously Dept of Physics). As my first degree ofBSc (Hons) was finalised in 1992, I satisfy the requirements of rule 12:39 a i) and ii) (General Course Rules Handbook - Admission requirements for Higher Doctoral Degrees) for application to the degree of Doctor of Science as a university graduate who is with standing of not less than eight years admission to a first degree at the University of Wollongong In relation to the requirement set out in 12:40, the academic unit associated most closely with my academic and research activities is the Department of Engineering Physics and more pointedly, the Centre for Medical Radiation Physics. The Centre for Medical Physics was inaugurated in 2005 under the direction of Prof Anatoly Rosenfeld. Medical radiation physics has been a subspecialty of the University ofWollongong\u27s Physics Department since the mid 1980\u27s when Dr Jagdish Mathur, introduced collaborative links with ANSTO (Australian Nuclear Science and Technology Organisation) and in 1990 with the newly formed ICCC (Illawarra Cancer Care Centre). The list of publications required of 12:40 is given in part 2 together with the estimated percentage contribution of the authors. In relation to 12:40 d) v), 12 of my early publications which are marked with an asterixis (*) were submitted and referenced as part of my original PhD in Medical Physics, completed at the University of Wollongong. Copies of publications submitted for consideration are presented in part 4 as required by 12:40. An overview that demonstrated that the collective works provide an original and significant contribution to knowledge: 12:40 is given in part 3. These publications have been divided into 3 broad streams of research and endeavour. Similarly, evidence that the publications have standing as significant and sustained contributions to knowledge 12:40 is presented throughout sections 3.2, 3.3 and 3.4 and in the form of summaries in subsections 3.2.1, 3.3.1 and 3.4.1. This is given together with a final summary (section 3.5) of the publications impact, journal citation indexes, citations and h-index

Skin dose from radiotherapy x-rays

The near surface build up characteristics of photon and electron beams used for radiotherapy treatment of cancer patients have been studied. For the measurement of skin dose various detectors were developed. The Attix parallel plate ionisation chamber was used as the benchmark chamber for in phantom dose build up measurements. Extrapolation of thermoluminescent dosimeters readings were employed to produce invivo results, within the first 0.1cm of tissue. A metal oxide semiconductor field effect transistor (MOSFET) system provided on line integral dosimetry. Radiochromic film was employed as an off-axis skin dose measurement. Neodymium Iron Boron rare earth lanthanide magnets were tested for their ability remove electron contamination from photon beams produced by a linear accelerator. Results show a reduced surface and build up dose. For a 20cm x 20cm field size at 100cm source surface distance (SSD) using a 0.6cm perspex block tray, percentage surface dose is 18% and 32% with and without the magnetic field applied respectively at 6MV . A helium/air replacement system has been developed which enhances the skin sparing properties of megavoltage photon beams by replacing 25cm of air above the phantom with helium. By combining the magnetic and helium devices the percentage surface dose is 9% of maximum. This is due to the elimination of low energy electron contamination normally generated in the air column. Monte Carlo simulations were performed in the build up region. Using experimental and Monte Carlo generated data as input, a model has been developed to predict central axis build up dose for 6MV photons. This is performed by separating dose components produced by i) photons scattered by the phantom and ii) electron contamination. Dose deposition changes depend on field size, source surface distance (SSD), angle of incidence, beam modifying devices (block trays, blocks and wedges) and patient geometry. The model accounts for these variables

Comparison of Epson scanner quality for radiochromic film evaluation

Epson Desktop scanners have been quoted as devices which match the characteristics required for the evaluation of radiation dose exposure by radiochromic films. Specifically, models such as the 10000XL have been used successfully for image analysis and are recommended by ISP for dosimetry purposes. This note investigates and compares the scanner characteristics of three Epson desktop scanner models including the Epson 10000XL, V700, and V330. Both of the latter are substantially cheaper models capable of A4 scanning. As the price variation between the V330 and the 10000XL is 20-fold (based on Australian recommended retail price), cost savings by using the cheaper scanners may be warranted based on results. By a direct comparison of scanner uniformity and reproducibility we can evaluate the accuracy of these scanners for radiochromic film dosimetry. Results have shown that all three scanners can produce adequate scanner uniformity and reproducibility, with the inexpensive V330 producing a standard deviation variation across its landscape direction of 0.7% and 1.2% in the portrait direction (reflection mode). This is compared to the V700 in reflection mode of 0.25% and 0.5% for landscape and portrait directions, respectively, and 0.5% and 0.8% for the 10000XL. In transmission mode, the V700 is comparable in reproducibility to the 10000XL for portrait and landscape mode, whilst the V330 is only capable of scanning in the landscape direction and produces a standard deviation in this direction of 1.0% compared to 0.6% (V700) and 0.25% (10000XL). Results have shown that the V700 and 10000XL are comparable scanners in quality and accuracy with the 10000XL obviously capable of imaging over an A3 area as opposed to an A4 area for the V700. The V330 scanner produced slightly lower accuracy and quality with uncertainties approximately twice as much as the other scanners. However, the results show that the V330 is still an adequate scanner and could be used for radiation dosimetry purposes. As such, if budgetary requirements are limited, the V700 scanner would be the recommended option at a price eight times cheaper than the 10000XL; however, the V330 produces adequate results at a price which is 2.5 times cheaper again. This may be a consideration for smaller institutions or individuals working with radiochromic film dosimetry

Scanner uniformity improvements for radiochromic film analysis with matt reflectance backing

A simple and reproducible method for increasing desktop scanner uniformity for the analysis of radiochromic films is presented. Scanner uniformity, especially in the non-scan direction, for transmission scanning is well known to be problematic for radiochromic film analysis and normally corrections need to be applied. These corrections are dependant on scanner coordinates and dose level applied which complicates dosimetry procedures. This study has highlighted that using reflectance scanning in combination with a matt, white backing material instead of the conventional gloss scanner finish, substantial increases in the scanner uniformity can be achieved within 90% of the scanning area. Uniformity within +/- 1% over the scanning area for our epsonV700 scanner tested was found. This is compared to within +/- 3% for reflection scanning with the gloss backing material and within +/- 4% for transmission scanning. The matt backing material used was simply 5 layers of standard quality white printing paper (80 g/m(2)). It was found that 5 layers was the optimal result for backing material however most of the improvements were seen with a minimum of 3 layers. Above 5 layers, no extra benefit was seen. This may eliminate the need to perform scanner corrections for position on the desktop scanners for radiochromic film dosimetry

The first author h-index (hfa-index): levelling the field for small and large institute medical and science scholars

Recent editorials and debates in the literature have highlighted the h-index measurement scale for researchers and how it can be used as a measure of their contributions to the medical and scientific community [1–5]. Indeed, in many University Institutions, the h-index (or h-factor) is being employed for assessment of regrading applications and for individual academics impact. So like it or not, it is here to stay and play. Whilst the debate will continue, it is definite that there are factors which can weight the h-index value to either advantage or disadvantage the researcher. Baldock [6] quite elegantly pointed out how subtle ways of citing papers can occur to benefit one’s h-index. This is inevitable. However, one area where substantial improvements could be made to the h-index may lie in the area of enhancing the h-index score by weighting first author papers or a hfa-index. This may not be practical if a large proportion of journals used alphabetical listings for authors. However this practice is not common and a well established researcher would normally publish in multiple journals reducing this overall effect. Upon investigation, according to the ISI Journal Citation Reports 2009, of the top 20 journals ranked in the subsection of ‘‘Radiology, Nuclear Medicine and Medical Imaging’’, no journals used alphabetical name order convention