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Rockhampton, Australia

Blunden S.,niversity Australia | Galland B.,University of Otago
Sleep Medicine Reviews | Year: 2014

The main aim of this paper is to consider relevant theoretical and empirical factors defining optimal sleep, and assess the relative importance of each in developing a working definition for, or guidelines about, optimal sleep, particularly in children. We consider whether optimal sleep is an issue of sleep quantity or of sleep quality. Sleep quantity is discussed in terms of duration, timing, variability and dose-response relationships. Sleep quality is explored in relation to continuity, sleepiness, sleep architecture and daytime behaviour. Potential limitations of sleep research in children are discussed, specifically the loss of research precision inherent in sleep deprivation protocols involving children. We discuss which outcomes are the most important to measure. We consider the notion that insufficient sleep may be a totally subjective finding, is impacted by the age of the reporter, driven by socio-cultural patterns and sleep-wake habits, and that, in some individuals, the driver for insufficient sleep can be viewed in terms of a cost-benefit relationship, curtailing sleep in order to perform better while awake. We conclude that defining optimal sleep is complex. The only method of capturing this elusive concept may be by somnotypology, taking into account duration, quality, age, gender, race, culture, the task at hand, and an individual's position in both sleep-alert and morningness-eveningness continuums. At the experimental level, a unified approach by researchers to establish standardized protocols to evaluate optimal sleep across paediatric age groups is required. © 2014 Elsevier Ltd. Source


Kinnear S.,niversity Australia
Marine Drugs | Year: 2010

Cylindrospermopsin (CYN) is rapidly being recognised as one of the most globally important of the freshwater algal toxins. The ever-expanding distribution of CYN producers into temperate zones is heightening concern that this toxin will represent serious human, as well as environmental, health risks across many countries. Since 1999, a number of studies have demonstrated the ability for CYN to bioaccumulate in freshwater organisms. This paper synthesizes the most current information on CYN accumulation, including notes on the global distribution of CYN producers, and a précis of CYN's ecological and human effects. Studies on the bioaccumulation of CYN are systematically reviewed, together with an analysis of patterns of accumulation. A discussion on the factors influencing bioaccumulation rates and potential is also provided, along with notes on detection, monitoring and risk assessments. Finally, key gaps in the existing research are identified for future study. © 2010 by the authors; licensee Molecular Diversity Preservation International. Source


Scott D.,niversity Australia | Scott D.,Menzies Research Institute | Blizzard L.,Menzies Research Institute | Fell J.,University of Tasmania | Jones G.,Menzies Research Institute
Arthritis Care and Research | Year: 2012

Objective. To examine the potential role of self-reported joint pain, stiffness, and dysfunction, and radiographic osteoarthritis (ROA), in sarcopenia progression and falls risk in older adults. Methods. Seven hundred nine older adults (50% women, mean ± SD age 62 ± 7 years) were examined at baseline and followup (mean ± SD 2.6 ± 0.4 years). ROA was assessed using the Altman atlas, and pain at 7 anatomic sites was self-reported. Dual X-ray absorptiometry assessed leg lean mass, dynamometry assessed knee extension and whole leg strength, leg muscle quality (LMQ) was calculated as whole leg strength relative to leg lean mass, and the Physiological Profile Assessment assessed falls risk. Results. In women only, baseline knee pain predicted a greater decline in knee extension strength, whole leg strength, and LMQ, and a greater increase in falls risk. Severe knee pain, stiffness, and dysfunction predicted greater declines in knee extension strength and increases in falls risk (all P < 0.05). Hip pain also predicted a greater decline in knee extension strength (-1.53 kg; 95% confidence interval [95% CI]-2.95,-0.11). No associations were observed between pain and sarcopenia indicators in men. Somewhat surprisingly, higher baseline total knee ROA score predicted a greater increase in mean leg lean mass (0.05 kg; 95% CI 0.02, 0.08) in both sexes. A path analysis demonstrated that knee ROA may contribute to declines in LMQ in women, through increases in pain, stiffness, and dysfunction. Conclusion. Knee and hip pain may directly contribute to the progression of sarcopenia and increased falls risk in older women. © 2012, American College of Rheumatology. Source


McClanachan M.,niversity Australia | Cole C.,niversity Australia
Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit | Year: 2012

Railway operators are continually increasing the length and weight of heavy haul trains to achieve reduced operating costs and increase network capacity. With longer and heavier trains, it becomes increasingly difficult for human operators to control the train optimally. The three main objectives of train control are minimizing journey time, minimizing energy usage, and minimizing in-train dynamics. This article reviews published train control optimization methods used in passenger, freight, and long heavy haul trains with a view of determining which methods would be best applied to the optimization of heavy haul train control. © Authors 2011. Source


Naweed A.,niversity Australia | Balakrishnan G.,niversity Australia
Road and Transport Research | Year: 2012

In the last decade, simulation technology has become a familiar feature in the Australian rail industry. This has been driven by a strong organisational intent to improve driver learning, and fuelled by the promise that train simulators enrich training, enhance decision support, and engender skills that transfer positively from the synthetic environment to the actual cab. This paper presents research that sets out to investigate how train simulators are currently being integrated into the rail organisation, and how industry end-users are utilising them to deliver training. Focus groups and observations were undertaken at a number of rail organisations that either owned simulators or were undergoing procurement. The data collected were analysed thematically and showed that, whilst practices for integration were varied, simulators were being extremely underutilised, in spite of their keen uptake. Further, effective application appeared hindered by a plethora of usability issues, concerns over technical reliability and simulator fidelity. The findings revealed one or more disconnects residing between the developer's promise and the organisational intent, which destabilised the process for fully integrating a simulator. This paper disentangles this dynamic by exploring the key obstructions impeding the path of effective simulator application. Source

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