Comparing exercise prescribed with exercise completed : effects of gender and mode of exercise

The purpose of this study was to compare the amount of exercise prescribed with the amount completed between two different modes of training intervention and between the sexes. Thirty-two men (mean age = 39.1 years, body mass index = 32.9 kg · m-2) and women (mean age = 39.6 years, body mass index = 32.1 kg · m-2) were prescribed traditional resistance training or light-resistance circuit training for 16 weeks. Lean mass and fat mass were determined by dual-energy X-ray absorptiometry at weeks 1 and 16. A completion index was calculated to provide a measure of the extent to which participants completed exercise training relative to the amount of exercise prescribed. The absolute amount of exercise completed by the circuit training group was significantly greater than the amount prescribed (P < 0.0001). The resistance training group consistently under-completed relative to the amount prescribed, but the difference was not significant. The completion index for the circuit training group (26 ± 21.7%) was significantly different from that of the resistance training group (-7.4 ± 3.0%). The completion index was not significantly different between men and women in either group. These data suggest that overweight and obese individuals participating in light-resistance circuit training complete more exercise than is prescribed. Men and women do not differ in the extent to which they over- or under-complete prescribed exercise.

Mild systemic hypoxia and photopic visual field sensitivity

Purpose: Flickering stimuli increase the metabolic demand of the retina,making it a sensitive perimetric stimulus to the early onset of retinal disease. We determine whether flickering stimuli are a sensitive indicator of vision deficits resulting from to acute, mild systemic hypoxia when compared to standard static perimetry. Methods: Static and flicker visual perimetry were performed in 14 healthy young participants while breathing 12% oxygen (hypoxia) under photopic illumination. The hypoxia visual field data were compared with the field data measured during normoxia. Absolute sensitivities (in dB) were analysed in seven concentric rings at 1°, 3°, 6°, 10°, 15°, 22° and 30° eccentricities as well as mean defect (MD) and pattern defect (PD) were calculated. Preliminary data are reported for mesopic light levels. Results: Under photopic illumination, flicker and static visual field sensitivities at all eccentricities were not significantly different between hypoxia and normoxia conditions. The mean defect and pattern defect were not significantly different for either test between the two oxygenation conditions. Conclusion: Although flicker stimulation increases cellular metabolism, flicker photopic visual field impairment is not detected during mild hypoxia. These findings contrast with electrophysiological flicker tests in young participants that show impairment at photopic illumination during the same levels of mild hypoxia. Potential mechanisms contributing to the difference between the visual fields and electrophysiological flicker tests including variability in perimetric data, neuronal adaptation and vascular autoregulation, are considered. The data have implications for the use of visual perimetry in the detection of ischaemic/hypoxic retinal disorders under photopic and mesopic light levels.

Best practice for prevention and treatment of cardiovascular disease through an equity lens : a review

Background: Despite declining rates of cardiovascular disease (CVD) mortality in developed countries, lower socioeconomic groups continue to experience a greater burden of the disease. There are now many evidence-based treatments and prevention strategies for the management of CVD and it is essential that their impact on the more disadvantaged group is understood if socioeconomic inequalities in CVD are to be reduced. Aims: To determine whether key interventions for CVD prevention and treatment are effective among lower socioeconomic groups, to describe barriers to their effectiveness and the potential or actual impact of these interventions on the socioeconomic gradient in CVD. Methods: Interventions were selected from four stages of the CVD continuum. These included smoking reduction strategies, absolute risk assessment, cardiac rehabilitation, secondary prevention medications, and heart failure self-management programmes. Electronic searches were conducted using terms for each intervention combined with terms for socioeconomic status (SES). Results: Only limited evidence was found for the effectiveness of the selected interventions among lower SES groups and there was little exploration of socioeconomic-related barriers to their uptake. Some broad themes and key messages were identified. In the majority of findings examined, it was clear that the underlying material, social and environmental factors associated with disadvantage are a significant barrier to the effectiveness of interventions. Conclusion: Opportunities to reduce socioeconomic inequalities occur at all stages of the CVD continuum. Despite this, current treatment and prevention strategies may be contributing to the widening socioeconomic-CVD gradient. Further research into the impact of best-practice interventions for CVD upon lower SES groups is required.

Legislative proposals to codify directors' liability for insolvent trading in Hong Kong : a 10-year journey

Hong Kong is a modern global city with a reputation for well-regulated financial markets, but for years, the government had been trying to enact laws on corporate rescue procedures with relatively little success. It is under the pretext of the Global Financial Crisis, the threat of a future economic meltdown gave the Hong Kong government the impetus to revisit this issue. This third attempt to codify statutory obligations on directors’ liability for insolvent trading has been criticised for either setting the standards too high or low for directors trading whilst insolvent. There is also some reservation given the beliefs and values of directors in Chinese family-owned and controlled companies. These companies would most likely trade out the difficult times. Nevertheless, this does not negate from the fact that the enactment of corporate rescue procedures in Hong Kong in 2010 is a momentous achievement for the Hong Kong government.

Carbon capture and storage laws in Australia : project facilitation or a precautionary approach?

Carbon capture and storage (CCS) is considered to be an integral transitionary measure in the mitigation of the global greenhouse gas emissions from our continued use of fossil fuels. Regulatory frameworks have been developed around the world and pilot projects have been commenced. However, CCS processes are largely untested at commercial scales and there are many unknowns associated with the long terms risks from these storage projects. Governments, including Australia, are struggling to develop appropriate, yet commercially viable, regulatory approaches to manage the uncertain long term risks of CCS activities. There have been numerous CCS regimes passed at the Federal, State and Territory levels in Australia. All adopt a different approach to the delicate balance facilitating projects and managing risk. This paper will examine the relatively new onshore and offshore regimes for CCS in Australia and the legal issues arising in relation to the implementation of CCS projects. Comparisons will be made with the EU CCS Directive where appropriate.

Molecular evolutionary dynamics of Ross River virus and implications for vaccine efficacy

Ross River virus (RRV) is a mosquito-borne member of the genus Alphavirus that causes epidemic polyarthritis in humans, costing the Australian health system at least US$10 million annually. Recent progress in RRV vaccine development requires accurate assessment of RRV genetic diversity and evolution, particularly as they may affect the utility of future vaccination. In this study, we provide novel RRV genome sequences and investigate the evolutionary dynamics of RRV from time-structured E2 gene datasets. Our analysis indicates that, although RRV evolves at a similar rate to other alphaviruses (mean evolutionary rate of approx. 8x10(-4) nucleotide substitutions per site year(-1)), the relative genetic diversity of RRV has been continuously low through time, possibly as a result of purifying selection imposed by replication in a wide range of natural host and vector species. Together, these findings suggest that vaccination against RRV is unlikely to result in the rapid antigenic evolution that could compromise the future efficacy of current RRV vaccines.

Vulnerability, insurance and policy: The learner driver's standard of care

In Cook v Cook the Australian High Court held that the standard of reasonable care owed by a learner driver to an instructor, conscious of the driver’s lack of experience, was lower than that owed to other passengers and road users. Recently, in Imbree v McNeilly, the High Court declined to follow this principle, concluding that the driver’s status or relationship with the claimant should no longer influence or alter the standard of care owed. The decision therefore provides an opportunity to re-examine the rationale and policy behind current jurisprudence governing the standard of care owed by learner drivers. In doing so, this article considers the principles relevant to determining the standard and Imbree’s implications for other areas of tort law and claimant v defendant relationships. It argues that Imbree was influenced by changing judicial perceptions concerning the vulnerability of driving instructors and the relevance of insurance to tortious liability.

Exploring the relationship between grandparents and their grandchild who has a disability

This thesis reports on the findings of a study which sought to explore the relationship between grandparents and their grandchild who has a disability. In contrast to previous studies, it presents the grandparents’ perspective on the roles and relationships they maintain within their families and adopts a qualitative approach to identify the meanings, symbols and beliefs grandparents attribute to their experiences. Grandparents have played and continue to play an important role in the lives of many families, contributing both symbolic and instrumental support to their grandchildren. Changing life expectancy for older people has meant that many more grandparents and grandchildren now have the opportunity to participate in meaningful interactions and to develop strong relationships. In the future, this will be true for great grandparents and in some cases great great grandparents as well. This presents a number of challenges to all concerned as family members negotiate the often complex arena of family life in the 21st Century. Realizing that a grandchild has a disability adds another degree of complexity to the negotiation of roles and responsibilities of grandparents within families. By focussing on grandparents experiences when their grandchild has a disability, this research both explores a knowledge gap in the current literature and more practicably, will inform both grandparents and their families as they negotiate these challenges. This research makes a significant contribution to knowledge in this area by exploring grandparents’ views on the differences in the relationship they have with their typically developing grandchildren and their grandchild with a disability; the impact having a grandchild with a disability had had on their grandparent identity and whether it impacted on quality of life. As well as reporting on the aims of the study, the papers presented in this thesis report on the key topics and themes identified in the analysis of the transcribed interviews conducted with 22 grandparents whose grandchild has a disability. Article 1 presents an overview of the literature which informs current knowledge in relation to grandparents, presenting a historical and theoretical perspective. Additionally, it presents previous literature which discusses the roles and styles grandparents adopt thus providing a framework which is later used to examine the roles and styles adopted by the grandparents in the study. Article 2 addresses the emotional responses grandparents in the study experienced as they grandparented a child with a disability. Comparing these emotions to that of a roller coaster ride, ranging from absolute sadness and grief to pride and delight, these findings highlight their unique experiences and will be reassuring for other grandparents who experience similar emotional responses. Article 3 discusses from the grandparents’ perspective, how having a grandchild with a disability has impacted on their family. Whilst reporting on the day to day challenges of competing family commitments and conflict, a number of grandparents in this study also commented that the experience had made them closer as a family and that there had been significant changes in how some individual family members now viewed people with disability. Article 4 explores the impact having a grandchild with a disability may have on the grandparents’ sense of identity and enactment of the grandparent role, utilising Neugarten and Weinstein’s (1964) classic grandparenting styles and Kornhaber’s (1996) concepts of latent and functional grandparent identity as a basis for comparison. It provides important insight into grandparenting identity when a child has a disability, suggesting that the grandparenting experience and role enactment may be universal with only the context and delivery varying. In summary, this thesis confirms the valuable role grandparents play in the lives of grandchildren who have a disability and their families. It identifies a number of implications and makes recommendations for future research and practice.

Technology strategy and competitive performance in bridge construction

Pragmatic construction professionals, accustomed to intense price competition and focused on the bottom line, have difficulty justifying investments in advanced technology. Researchers and industry professionals need improved tools to analyze how technology affects the performance of the firm. This paper reports the results of research to begin answering the question, “does technology matter?” The researchers developed a set of five dimensions for technology strategy, collected information regarding these dimensions along with four measures of competitive performance in five bridge construction firms, and analyzed the information to identify relationships between technology strategy and competitive performance. Three technology strategy dimensions—competitive positioning, depth of technology strategy, and organizational fit—showed particularly strong correlations with the competitive performance indicators of absolute growth in contract awards and contract award value per technical employee. These findings indicate that technology does matter. The research also provides ways to analyze options for approaching technology and ways to relate technology to competitive performance for use by managers. It also provides a valuable set of research measures for technology strategy.

Validation and automation of the DYNJAWS component module of the BEAMnrc Monte Carlo code

The purpose of this work is to validate and automate the use of DYNJAWS; a new component module (CM) in the BEAMnrc Monte Carlo (MC) user code. The DYNJAWS CM simulates dynamic wedges and can be used in three modes; dynamic, step-and-shoot and static. The step-and-shoot and dynamic modes require an additional input file defining the positions of the jaw that constitutes the dynamic wedge, at regular intervals during its motion. A method for automating the generation of the input file is presented which will allow for the more efficient use of the DYNJAWS CM. Wedged profiles have been measured and simulated for 6 and 10 MV photons at three field sizes (5 cm x 5 cm , 10 cm x10 cm and 20 cm x 20 cm), four wedge angles (15, 30, 45 and 60 degrees), at dmax and at 10 cm depth. Results of this study show agreement between the measured and the MC profiles to within 3% of absolute dose or 3 mm distance to agreement for all wedge angles at both energies and depths. The gamma analysis suggests that dynamic mode is more accurate than the step-and-shoot mode. The DYNJAWS CM is an important addition to the BEAMnrc code and will enable the MC verification of patient treatments involving dynamic wedges.

Strategies for appropriate technology and competitive performance in infrastructure construction

Earlier research developed theoretically-based aggregate metrics for technology strategy and used them to analyze California bridge construction firms (Hampson, 1993). Determinants of firm performance, including trend in contract awards, market share and contract awards per employee, were used as indicators for competitive performance. The results of this research were a series of refined theoretically-based measures for technology strategy and a demonstrated positive relationship between technology strategy and competitive performance within the bridge construction sector. This research showed that three technology strategy dimensions—competitive positioning, depth of technology strategy, and organizational fit— show very strong correlation with the competitive performance indicators of absolute growth in contract awards, and contract awards per employee. Both researchers and industry professionals need improved understanding of how technology affects results, and how to better target investments to improve competitive performance in particular industry sectors. This paper builds on the previous research findings by evaluating the strategic fit of firms' approach to technology with industry segment characteristics. It begins with a brief overview of the background regarding technology strategy. The major sections of the paper describe niches and firms in an example infrastructure construction market, analyze appropriate technology strategies, and describe managerial actions to implement these strategies and support the business objectives of the firm.

Commissioning of a Geant4 based treatment plan simulation tool : linac model and dicom-rt interface

A Geant4 based simulation tool has been developed to perform Monte Carlo modelling of a 6 MV VarianTM iX clinac. The computer aided design interface of Geant4 was used to accurately model the LINAC components, including the Millenium multi-leaf collimators (MLCs). The simulation tool was verified via simulation of standard commissioning dosimetry data acquired with an ionisation chamber in a water phantom. Verification of the MLC model was achieved by simulation of leaf leakage measurements performed using GafchromicTM film in a solid water phantom. An absolute dose calibration capability was added by including a virtual monitor chamber into the simulation. Furthermore, a DICOM-RT interface was integrated with the application to allow the simulation of treatment plans in radiotherapy. The ability of the simulation tool to accurately model leaf movements and doses at each control point was verified by simulation of a widely used intensity-modulated radiation therapy (IMRT) quality assurance (QA) technique, the chair test.

A hybrid radiation detector for simultaneous spatial and temporal dosimetry

In this feasibility study an organic plastic scintillator is calibrated against ionisation chamber measurements and then embedded in a polymer gel dosimeter to obtain a quasi-4D experimental measurement of a radiation field. This hybrid dosimeter was irradiated with a linear accelerator, with temporal measurements of the dose rate being acquired by the scintillator and spatial measurements acquired with the gel dosimeter. The detectors employed in this work are radiologically equivalent; and we show that neither detector perturbs the intensity of the radiation field of the other. By employing these detectors in concert, spatial and temporal variations in the radiation intensity can now be detected and gel dosimeters can be calibrated for absolute dose from a single irradiation.

Real estate agents, brochure and misleading or deceptive conduct

The decision of the High Court in Butcher v Lachlan Elder Realty Pty Ltd [2004] HCA 60 involves issues that affect every person who is induced to buy real estate in Australia by statements in sales brochures distributed by real estate agents. One of these issues is the extent to which estate agents unwittingly engage in misleading or deceptive conduct under s 52 of the Trade Practices Act 1974 (Cth) (‘the Act’) when they distribute sales brochures that contain untrue or misleading statements prepared by others. A further issue is the extent to which agents can escape liability by relying on disclaimers about the authenticity of false statements contained in brochures prepared by them.