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Background: The treatment of cancer with radiation uses advanced techniques such as intensity modulated and stereotactic radiotherapy. These modalities can provide sub millimetre accuracy, delivering high radiation dose to the tumour and reduced dose to the surrounding normal anatomy. Building a mental model of the size, shape and position of the tumour in relation to the surrounding anatomy and proposed radiation beam direction requires radiotherapy radiographers to have well developed three- spatial visualisation skills. The introduction of the Virtual Environment for Radiotherapy Training (Vertual Ltd, Hull, United Kingdom), an immersive 3-D visualisation platform in 2007, offered the potential for developing new ways of supporting the development of these visualisation skills in pre-registration radiotherapy learners in a simulated environment. Aims: This programme of research aimed to measure the baseline three dimensional spatial visualisation skills of new radiotherapy learners, to compare their performance with new learners in diagnostic imaging, to determine if 3-D visualisation skills could develop over time and to identify those learners most likely to benefit from learning in the virtual environment for radiotherapy training. Methods: This programme of research employed a QUANT + qual mixed model approach with purposive convenience sampling of year one diagnostic imaging and radiotherapy students to develop an online, three-dimensional spatial visualisation test using objects from two traditional paper based spatial visualisation tests for mental rotation and cross sectional visual perception (the pilot phase). The experimental phase employed an online test platform in a controlled, single subject design, longitudinal study using a second cohort of students to determine their 3-D spatial visualisation skill at the start of their pre-registration radiography programme and to track any change over three additional time points during an 18-month period between the start of year one and the end of year two. For the radiotherapy cohort, the relationship between baseline spatial visualisation skill and patient positioning performance was investigated using a simulated treatment delivery task conducted within the Virtual Environment for Radiotherapy Training. Results: The pilot phase comparison of performance scores for the paper based and online versions of the three-dimensional spatial visualisation test did not produce statistically significant differences, suggesting that a move to an online test platform would not disadvantage any participant. Results from the experimental phase (study four) identified that the baseline 3-D spatial visualisation skill of 54 pre-registration learners in radiotherapy (n = 15) and diagnostic imaging (n = 39) could be measured and performance classified as being low, intermediate or high at the start of their radiography education. Across both pathways, 13 participants (24%) were identified as having low skill, 36 (67%) were intermediate and 5 (9%). Performance gains were observed in the growth trajectory for mean spatial visualisation test score over the 18 month time period for both pathways. Analysis of performance in the mental rotation and cross section subcomponents indicated that one third of all participants might benefit from additional support in mental rotation or perception of cross sections. For the radiotherapy positioning task, correlations between task performance metrics for task completion time, number of equipment adjustments and set up accuracy and baseline demonstrated a weak positive relationship meaning that the results were inconclusive. Conclusions and contributions to knowledge: The measurement of 3-D spatial visualisation subcomponent performance as a surrogate for accurate patient positioning and beam alignment has provided an enhanced understanding of baseline visualisation skill. Analysis of these subcomponents, with an emphasis on patterns of incorrect answers, in addition to overall performance score provides a method for identifying those individuals with less well-developed skills. These are the learners who may have difficulty with mental model and relationship building and would benefit from the additional support of focused tutorials with personalised spatial visualisation syllabus activities. This enhanced understanding will provide opportunities for the development of the spatial visualisation syllabus beyond the often opportunistic, and ad-hoc structure of clinical practice and a one-size fits all approach to campus based simulation and visualisation activities.

The rising prevalence of overweight and obese children has seen a focus upon school-based interventions. However, little research has considered the impact of the school context on pupil weight status. The aim of this project was to identify whether primary schools have an impact upon pupil weight status, and subsequently explore which, if any, school-based contextual factors were associated with pupil weight status. Reviewing the relevant literature identified two gaps in the evidence related to primary school built environment and policy, and weight status, which were examined through systematic reviews. These reviews highlighted the paucity of literature on the school influence on pupil weight status, demonstrating the need for more research. Subsequently, the main component of the research was a repeated cross-sectional study using secondary data from the National Child Measurement Programme and additional sources. The reviews highlighted the need for studies to examine multiple contexts simultaneously, and although restricted to the school, sufficient data were available to examine the socio-demographic, built environment, physical activity, diet and ethos contexts of schools. The final data set comprised 62,554 participants, over 300 schools and 40 potential explanatory variables across five academic years (2006/07 - 2010/11). Both continuous and binary measures of weight status were assessed using national and international definitions and each academic year was analysed separately. Multilevel modelling allowed the estimation of how much of the variation in pupil weight status related to differences between schools and between-year groups within-schools, both of which were found to be small (intraclass correlation coefficient <0.03 (body mass index standard deviation score and overweight), -0.05 (obesity)). It was not possible to differentiate between schools. Primarily only two school-based contextual factors were statistically significant predictors in each academic year, mostly related to the socioeconomic status and ethos of the school; however these did not remain consistent across academic years. The small impact of schools, led to the consideration of whether the shared experience of attending school 'stabilised' children's growth.

The current primary standards at NPL for the measurement of absorbed dose to water in high energy photon and electron beams are graphite calorimeters. However, the quantity of interest in radiation dosimetry is absorbed dose to water. Therefore, a new absorbed dose to water standard based on water calorimetry has been developed for use in high energy photon and electron beams. The calorimeter operates at 4 °C, vsath temperature control being provided by liquid cooling. The sealed glass inner vessel of the calorimeter was designed to minimise the effect of non-water materials on the measurement of absorbed dose. The temperature sensing thermistor probes were designed and constructed so that glass is the only material in contact with high purity water inside the vessel. Initial measurements of absorbed dose to water made in 6, 10, and 19 MV photons, and 16 MeV electrons agreed, within the measurement uncertainties of approximately 1.5% (95% c.l.), with those determined by graphite calorimetry. These measurements confirmed the feasibility of the calorimeter design. Significant improvements have been made to the temperature measurement system, the water phantom and its temperature controlled enclosure since these measurements were performed, reducing the estimated uncertainty on the measurement of absorbed dose to water to 1% (95% c.l.), although further work is required before the calorimeter can be used as a primary standard.

Delaware Technical and Community College online courses are not properly focused to ensure instructors are effective in improving student achievement. First time online students are not given the proper tools when navigating online courses at the college. The focus at Delaware Tech should be on improving the format which students use when navigating an online course; this would improve success and completion rates in these courses. This paper provides the guide for high quality online development and instruction, quality professional development, and college-wide reform that would result in the improvement of online course content. Analysis of Delaware Technical and Community College, Terry Campus in Dover, Delaware, provides insight to how online courses are developed and taught and the process which instructors must follow to be eligible to teach online. Recommendations for policy are based on the literature and the analysis of the E-Learning Committee at Delaware Tech, Terry Campus. Policy recommendations include (1) altering the course that is used to teach first time online instructors, (2) implementing mandatory training for all prospective online instructors, (3) providing a mentor for first time online instructors, (4) offering different delivery methods for the instructor training course, (5) providing a Blackboard tutorial for online students, (6) providing a Blackboard training course for first time online students, and (7) implementing as a part of the college entrance exam a skills assessment centered around online navigating abilities. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]