Scaffolding reflective inquiry - enabling why-questioning while e-Learning

This paper presents some theoretical and interdisciplinary perspectives that might inform the design and development of information and communications technology (ICT) tools to support reflective inquiry during e-learning. The role of why-questioning provides the focus of discussion and is guided by literature that spans critical thinking, inquiry-based and problem-based learning, storytelling, sense-making, and reflective practice, as well as knowledge management, information science, computational linguistics and automated question generation. It is argued that there exists broad scope for the development of ICT scaffolding targeted at supporting reflective inquiry duringe-learning. Evidence suggests that wiki-based learning tasks, digital storytelling, and e-portfolio tools demonstrate the value of accommodating reflective practice and explanatory content in supporting learning; however, it is also argued that the scope for ICT tools that directly support why-questioning as a key aspect of reflective inquiry is a frontier ready for development.

Local Commons : communicating local issues through place-based interventions

Due to the numerous possibilities of voicing concerns and the flood of data we are exposed to, local issues are at a risk of being overlooked. Following a research agenda proposed by Foth et al. (2013), this thesis explored the possible contributions of situated digital and tangible media for communicating local issues. Making use of the location of an issue could thereby not only allow to reach the targeted audience but also for a deeper involvement of citizens. Through the development of a design intervention in public space, called Local Commons, the benefits of this approach were investigated. Therefore, the intervention combined digital and tangible media in order to engage the public to contribute and debate different perspectives on a given local issue. The interaction with the intervention was thereby twofold. First, the intervention invited the audience to submit images of their perspectives on the issue, which were displayed on a public screen. Via tangible buttons in front of the screen, the audience then had the possibility to agree or disagree to the displayed perspectives, creating a space for deliberation. In a field study, the concept was subsequently tested and evaluated. The results of this study, although not generalisable, supported the chosen approach of this thesis.

Embedding EfS in teacher education : an introductory guide to using the systems change model

Welcome to this introductory guide on using a systems change model to embed Education for Sustainability (EfS) into teacher education. Pressing sustainability issues such as climate change, biodiversity loss and depletion of non-renewable resources pose new challenges for education. The importance of education in preparing future citizens to engage in sustainable living practices and help create a more sustainable world is widely acknowledged. As a result many universities around the world are beginning to recognize the need to integrate EfS into their teacher education programs. However, evidence indicates that there is little or no core EfS knowledge or pedagogy in pre-service teacher courses available to student teachers in a thorough and systematic fashion. Instead efforts are fragmented and individually or, at best, institutionally-based and lacking a systems approach to change, an approach that is seen as essential to achieving a sustainable society (Henderson & Tilbury, 2004). The result is new teachers are graduating without the necessary knowledge or skills to teach in ways that enable them to prepare their students to cope well with the new and emerging challenges their communities face. This guide has been prepared as part of a teaching and learning research project that applied a systems change approach to embedding the learning and teaching of sustainability into pre-service teacher education. The processes, outcomes and lessons learnt from this project are presented here as a guide for navigating pathways to systemic change in the journey of re-orienting teacher education towards sustainability. The guide also highlights how a systems change approach can be used to successfully enact change within a teacher education system. If you are curious about how to introduce and embed EfS into teacher education – or have tried other models and are looking for a more encompassing, transformative approach – this guide is designed to help you. The material presented in this guide is designed to be flexible and adaptive. However you choose to use the content, our aim is to help you and your students develop new perspectives, promote discussion and to engage with a system-wide approach to change.

TEXTA Book Club in the QUT Art Museum

TEXTA runs as a type of book club that we have previously labelled as ‘bespoke’ (Ellison, Holliday and Van Luyn 2012). We visualise TEXTA as a meeting place between the community and the university, as a space for discussion and engagement with both visual art forms and written texts. In today’s presentation, we shall briefly establish the ‘bespoke’ bookclub. We then want to introduce the idea of TEXTA as an example of a book club that negotiates Edward Soja’s Thirdspace (1996) – a space that incorporates and extends concepts of First and Secondspace (or perceived and conceived spaces). In doing so, we showcase two recent sessions of TEXTA as case studies. We will then illustrate some ideas we have for expanding TEXTA beyond the boundaries of Brisbane city, and invite feedback on how to further extend the opportunities for community engagement that TEXTA can offer in regional areas.

Building sensitising terms to understand free-play in open-ended interactive art environments

In this paper we introduce and discuss the nature of free-play in the context of three open-ended interactive art installation works. We observe the interaction work of situated free-play of the participants in these environments and, building on precedent work, devise a set of sensitising terms derived both from the literature and from what we observe from participants interacting there. These sensitising terms act as guides and are designed to be used by those who experience, evaluate or report on open-ended interactive art. That is, we propose these terms as a common-ground language to be used by participants communicating while in the art work to describe their experience, by researchers in the various stages of research process (observation, coding activity, analysis, reporting, and publication), and by inter-disciplinary researchers working across the fields of HCI and art. This work builds a foundation for understanding the relationship between free-play, open-ended environments, and interactive installations and contributes sensitising terms useful for the HCI community for discussion and analysis of open-ended interactive art works.

Commissioning of a new commercial plastic scintillator system for radiotherapy

Introduction Since 1992 there have been several articles published on research on plastic scintillators for use in radiotherapy. Plastic scintillators are said to be tissue equivalent, temperature independent and dose rate independent [1]. Although their properties were found to be promising for measurements in megavoltage X-ray beams there were some technical difficulties with regards to its commercialisation. Standard Imaging has produced the first commercial system which is now available for use in a clinical setting. The Exradin W1 scintillator device uses a dual fibre system where one fibre is connected to the Plastic Scintillator and the other fibre only measures Cerenkov radiation [2]. This paper presents results obtained during commissioning of this dosimeter system. Methods All tests were performed on a Novalis Tx linear accelerator equipped with a 6 MV SRS photon beam and conventional 6 and 18 MV X-ray beams. The following measurements were performed in a Virtual Water phantom at a depth of dose maximum. Linearity: The dose delivered was varied between 0.2 and 3.0 Gy for the same field conditions. Dose rate dependence: For this test the repetition rate of the linac was varied between 100 and 1,000 MU/min. A nominal dose of 1.0 Gy was delivered for each rate. Reproducibility: A total of five irradiations for the same setup. Results The W1 detector gave a highly linear relationship between dose and the number of Monitor Units delivered for a 10 9 10 cm2 field size at a SSD of 100 cm. The linearity was within 1 % for the high dose end and about 2 % for the very low dose end. For the dose rate dependence, the dose measured as a function of repetition the rate (100–1,000 MU/min) gave a maximum deviation of 0.9 %. The reproducibility was found to be better than 0.5 %. Discussion and conclusions The results for this system look promising so far being a new dosimetry system available for clinical use. However, further investigation is needed to produce a full characterisation prior to use in megavoltage X-ray beams.

Surface dosimetry for very small X-ray beams

Introduction The dose to skin surface is an important factor for many radiotherapy treatment techniques. It is known that TPS predicted surface doses can be significantly different from actual ICRP skin doses as defined at 70 lm. A number of methods have been implemented for the accurate determination of surface dose including use of specific dosimeters such as TLDs and radiochromic film as well as Monte Carlo calculations. Stereotactic radiosurgery involves delivering very high doses per treatment fraction using small X-ray fields. To date, there has been limited data on surface doses for these very small field sizes. The purpose of this work is to evaluate surface doses by both measurements and Monte Carlo calculations for very small field sizes. Methods All measurements were performed on a Novalis Tx linear accelerator which has a 6 MV SRS X-ray beam mode which uses a specially thin flattening filter. Beam collimation was achieved by circular cones with apertures that gave field sizes ranging from 4 to 30 mm at the isocentre. The relative surface doses were measured using Gafchromic EBT3 film which has the active layer at a depth similar to the ICRP skin dose depth. Monte Carlo calculations were performed using the BEAMnrc/EGSnrc Monte Carlo codes (V4 r225). The specifications of the linear accelerator, including the collimator, were provided by the manufacturer. Optimisation of the incident X-ray beam was achieved by an iterative adjustment of the energy, spatial distribution and radial spread of the incident electron beam striking the target. The energy cutoff parameters were PCUT = 0.01 MeV and ECUT = 0.700 - MeV. Directional bremsstrahlung splitting was switched on for all BEAMnrc calculations. Relative surface doses were determined in a layer defined in a water phantom of the same thickness and depth as compared to the active later in the film. Results Measured surface doses using the EBT3 film varied between 13 and 16 % for the different cones with an uncertainty of 3 %. Monte Carlo calculated surface doses were in agreement to better than 2 % to the measured doses for all the treatment cones. Discussion and conclusions This work has shown the consistency of surface dose measurements using EBT3 film with Monte Carlo predicted values within the uncertainty of the measurements. As such, EBT3 film is recommended for in vivo surface dose measurements.

Monte Carlo simulations of small field output factors in solid phantoms

Introduction Total scatter factor (or output factor) in megavoltage photon dosimetry is a measure of relative dose relating a certain field size to a reference field size. The use of solid phantoms has been well established for output factor measurements, however to date these phantoms have not been tested with small fields. In this work, we evaluate the water equivalency of a number of solid phantoms for small field output factor measurements using the EGSnrc Monte Carlo code. Methods The following small square field sizes were simulated using BEAMnrc: 5, 6, 7, 8, 10 and 30 mm. Each simulated phantom geometry was created in DOSXYZnrc and consisted of a silicon diode (of length and width 1.5 mm and depth 0.5 mm) submersed in the phantom at a depth of 5 g/cm2. The source-to-detector distance was 100 cm for all simulations. The dose was scored in a single voxel at the location of the diode. Interaction probabilities and radiation transport parameters for each material were created using custom PEGS4 files. Results A comparison of the resultant output factors in the solid phantoms, compared to the same factors in a water phantom are shown in Fig. 1. The statistical uncertainty in each point was less than or equal to 0.4 %. The results in Fig. 1 show that the density of the phantoms affected the output factor results, with higher density materials (such as PMMA) resulting in higher output factors. Additionally, it was also calculated that scaling the depth for equivalent path length had negligible effect on the output factor results at these field sizes. Discussion and conclusions Electron stopping power and photon mass energy absorption change minimally with small field size [1]. Also, it can be seen from Fig. 1 that the difference from water decreases with increasing field size. Therefore, the most likely cause for the observed discrepancies in output factors is differing electron disequilibrium as a function of phantom density. When measuring small field output factors in a solid phantom, it is important that the density is very close to that of water.

Prostate radiotherapy treatment plan quality : effects of hip prostheses

Introduction This study aimed to examine the geometric and dosimetric results when radiotherapy treatment plans are designed for prostate cancer patients with hip prostheses. Methods Ten EBRT treatment plans for localised prostate cancer, in the presence of hip prostheses, were analysed and compared with a reference set of 196 treatment plans for localised prostate cancer in patients without prostheses. Crowe et al.’s TADA code [1] was used to extract treatment plan parameters and evaluate doses to target volumes and critical structures against recommended goals [2] and constraints [3, 4]. Results The need to avoid transmitting the radiation beam through the hip prostheses limited the range of gantry angles available for use in both the rotational (VMAT) and the non-rotational (3DCRT and IMRT) radiotherapy treatments. This geometric limitation (exemplified in the VMAT data shown in Fig. 1) reduced the overall quality of the treatment plans for patients with prostheses compared to the reference plans. All plans with prostheses failed the PTV dose homogeneity requirement [2], whereas only 4 % of the plans without prostheses failed this test. Several treatment plans for patients with hip prostheses also failed the QUANTEC requirements that less than 50 % of the rectum receive 50 Gy and less than 35 % of the rectum receive 60 Gy to keep the grade 3 toxicity rate below 10 % [3], or the Hansen and Roach requirement that less than 25 % of the bladder receive 75 Gy [4]. Discussion and conclusions The results of this study exemplify the difficulty of designing prostate radiotherapy treatment plans, where beams provide adequate doses to targeted tissues while avoiding nearby organs at risk, when the presence of hip prostheses limits the available treatment geometries. This work provides qualitative evidence of the compromised dose distributions that can result, in such cases.

A diode for correction-less small field output factor measurements

Introduction Due to their high spatial resolution diodes are often used for small field relative output factor measurements. However, a field size specific correction factor [1] is required and corrects for diode detector over-response at small field sizes. A recent Monte Carlo based study has shown that it is possible to design a diode detector that produces measured relative output factors that are equivalent to those in water. This is accomplished by introducing an air gap at the upstream end of the diode [2]. The aim of this study was to physically construct this diode by placing an ‘air cap’ on the end of a commercially available diode (the PTW 60016 electron diode). The output factors subsequently measured with the new diode design were compared to current benchmark small field output factor measurements. Methods A water-tight ‘cap’ was constructed so that it could be placed over the upstream end of the diode. The cap was able to be offset from the end of the diode, thus creating an air gap. The air gap width was the same as the diode width (7 mm) and the thickness of the air gap could be varied. Output factor measurements were made using square field sizes of side length from 5 to 50 mm, using a 6 MV photon beam. The set of output factor measurements were repeated with the air gap thickness set to 0, 0.5, 1.0 and 1.5 mm. The optimal air gap thickness was found in a similar manner to that proposed by Charles et al. [2]. An IBA stereotactic field diode, corrected using Monte Carlo calculated kq,clin,kq,msr values [3] was used as the gold standard. Results The optimal air thickness required for the PTW 60016 electron diode was 1.0 mm. This was close to the Monte Carlo predicted value of 1.15 mm2. The sensitivity of the new diode design was independent of field size (kq,clin,kq,msr = 1.000 at all field sizes) to within 1 %. Discussion and conclusions The work of Charles et al. [2] has been proven experimentally. An existing commercial diode has been converted into a correction-less small field diode by the simple addition of an ‘air cap’. The method of applying a cap to create the new diode leads to the diode being dual purpose, as without the cap it is still an unmodified electron diode.

The importance of accurate beam data measurement for SRT/SRS treatment planning

Introduction This study investigated the sensitivity of calculated stereotactic radiotherapy and radiosurgery doses to the accuracy of the beam data used by the treatment planning system. Methods Two sets of field output factors were acquired using fields smaller than approximately 1 cm2, for inclusion in beam data used by the iPlan treatment planning system (Brainlab, Feldkirchen, Germany). One set of output factors were measured using an Exradin A16 ion chamber (Standard Imaging, Middleton, USA). Although this chamber has a relatively small collecting volume (0.007 cm3), measurements made in small fields using this chamber are subject to the effects of volume averaging, electronic disequilibrium and chamber perturbations. The second, more accurate, set of measurements were obtained by applying perturbation correction factors, calculated using Monte Carlo simulations according to a method recommended by Cranmer-Sargison et al. [1] to measurements made using a 60017 unshielded electron diode (PTW, Freiburg, Germany). A series of 12 sample patient treatments were used to investigate the effects of beam data accuracy on resulting planned dose. These treatments, which involved 135 fields, were planned for delivery via static conformal arcs and 3DCRT techniques, to targets ranging from prostates (up to 8 cm across) to meningiomas (usually more than 2 cm across) to arterioveinous malformations, acoustic neuromas and brain metastases (often less than 2 cm across). Isocentre doses were calculated for all of these fields using iPlan, and the results of using the two different sets of beam data were evaluated. Results While the isocentre doses for many fields are identical (difference = 0.0 %), there is a general trend for the doses calculated using the data obtained from corrected diode measurements to exceed the doses calculated using the less-accurate Exradin ion chamber measurements (difference\0.0 %). There are several alarming outliers (circled in the Fig. 1) where doses differ by more than 3 %, in beams from sample treatments planned for volumes up to 2 cm across. Discussion and conclusions These results demonstrate that treatment planning dose calculations for SRT/SRS treatments can be substantially affected when beam data for fields smaller than approximately 1 cm2 are measured inaccurately, even when treatment volumes are up to 2 cm across.

Response variation of optically stimulated luminescence dosimeters

Introduction This study investigates uncertainties pertaining to the use of optically stimulated luminescence dosimeters (OSLDs) in radiotherapy dosimetry. The sensitivity of the luminescent material is related to the density of recombination centres [1], which is in the range of 1015–1016 cm-3. Because of this non-uniform distribution of traps in crystal growth the sensitivity varies substantially within a batch of dosimeters. However, a quantitative understanding of the relationship between the response of an OSLD and its sensitive volume has not yet been investigated or reported in literature. Methods In this work, OSLDs are scanned with a MicroCT scanner to determine potential sources for the variation in relative sensitivity across a selection of Landauer nanoDot dosimeters. Specifically, the correlation between a dosimeters relative sensitivity and the loading density of Al2O3:C powder was determined. Results When extrapolating the sensitive volume’s radiodensity from the CT data, it was shown that there is a non-uniform distribution incrystal growth as illustrated in Fig. 1. A plot of voxel count versus the element-specific correction factor is shown in Fig. 2 where each point represents a single OSLD. A line was fitted which has an R2-value of 0.69 and a P-value of 8.21 9 10-19. This data shows that the response of a dosimeter decreases proportionally with sensitive volume. Extrapolating from this data, a quantitative relationship between response and sensitive volume was roughly determined for this batch of dosimeters. A change in volume of 1.176 9 10-5 cm3 corresponds to a 1 % change in response. In other words, a 0.05 % change in the nominal volume of the chip would result in a 1 % change in response. Discussion and conclusions This work demonstrated that the amount of sensitive material is approximately linked to the total correction factor. Furthermore, the ‘true’ volume of an OSLD’s sensitive material is, on average, 17.90 % less than that which has been reported in literature, mainly due to the presence of air cavities in the material’s structure. Finally, the potential effects of the inaccuracy of Al2O3:C deposition increases with decreasing chip size. If a luminescent dosimeter were manufactured with a smaller volume than currently employed using the same manufacturing protocol, the variation in response from chip to chip would more than likely exceed the current 5 % range.

A sample review of Deeds of Company Arrangement under Part 5.3A of the Corporations Act

An empirical review of the operation of Part 5.3A of the Corporations Act 2001 (Cth) is timely given that Australia’s corporate rescue regime marked its 20 year anniversary in 2013. The research project culminating in this report was funded by the 2013 ARITA Terry Taylor Scholarship and entailed a review of a random sample of 72 executed DOCAs (and associated reports and returns) which were effectuated between 1 August 2012 and 31 July 2013. This sample review of DOCAs was undertaken with the intention of producing a ‘snapshot’ of current practices and trends pertaining to DOCAs – ie, average (or typical) rate of dividends paid, the outcomes or goals which DOCAs customarily achieve (eg, genuine company rescues, workouts, enhanced asset realisations or ‘quasi-liquidations’), the profile of the companies executing DOCAs and the average term/duration of DOCAs. The purpose and value of this sample review was to empirically assess the use and effectiveness of one important aspect of Part 5.3A and to further inform consideration and debate as to whether changes are warranted to Australia’s voluntary administration regime.

Good choices, great future : an applied theatre prevention program to reduce alcohol-related risky behaviours during Schoolies

Introduction and Aims. The contextual and temporal factors of post-school celebratory events ('Schoolies') place young people at elevated risk of excessive drinking compared with other social occasions. This study investigates the impact of an applied theatre prevention program 'Choices' in reducing the risk of drinking and other risk behaviours during Schoolies celebrations. Design and Methods. Choices was delivered in the last term of Year 12 across 28 North Queensland schools. A total of 352 school leavers (43.1% male, mean age=17.14years) completed a questionnaire at Whitsunday Schoolies, Queensland, Australia on 23-24 November 2010. Nearly 49% of respondents had attended Choices. The survey included measures of alcohol use, illicit drug use and associated problems during Schoolies and a month prior to Schoolies. Results. After controlling for gender and pre-Schoolies drinking, school leavers who attended Choices were significantly less likely to report illicit drug use (OR=0.51, P<0.05) and problem behaviours (OR=0.40, P<0.01) than those who did not attend Choices. There was, however, no intervention effect in risky drinking (i.e. drank on 5 or more days, typical amount five or more standard drink and binge drank on 3 or more days) at Schoolies (OR=0.92, P=0.80). Discussion and Conclusions. Delivery of a youth-specific applied theatre prevention program employing a harm minimisation framework may be effective in reducing high-risk behaviours associated with alcohol consumption at celebratory events, even if young people expect to engage in excessive alcohol consumption. [Quek L-H, White A, Low C, Brown J, Dalton N, Dow D, Connor JP. Good choices, great future: An applied theatre prevention program to reduce alcohol-related risky behaviours during Schoolies. Drug Alcohol Rev 2012;31:897–902]

The topography of multiple drug use among adolescent Australians : findings from the National Drug Strategy Household Survey

Introduction and aims: Despite evidence that many Australian adolescents have considerable experience with various drug types, little is known about the extent to which adolescents use multiple substances. The aim of this study was to examine the degree of clustering of drug types within individuals, and the extent to which demographic and psychosocial predictors are related to cluster membership. Design and method: A sample of 1402 adolescents aged 12-17. years were extracted from the Australian 2007 National Drug Strategy Household Survey. Extracted data included lifetime use of 10 substances, gender, psychological distress, physical health, perceived peer substance use, socioeconomic disadvantage, and regionality. Latent class analysis was used to determine clusters, and multinomial logistic regression employed to examine predictors of cluster membership. Result: There were 3 latent classes. The great majority (79.6%) of adolescents used alcohol only, 18.3% were limited range multidrug users (encompassing alcohol, tobacco, and marijuana), and 2% were extended range multidrug users. Perceived peer drug use and psychological distress predicted limited and extended multiple drug use. Psychological distress was a more significant predictor of extended multidrug use compared to limited multidrug use. Discussion and conclusion: In the Australian school-based prevention setting, a very strong focus on alcohol use and the linkages between alcohol, tobacco and marijuana are warranted. Psychological distress may be an important target for screening and early intervention for adolescents who use multiple drugs.