Electromyographic activity in lower limb muscles is temporally associated with the slow phase of oxygen uptake during cycling

Although the "slow" phase of pulmonary oxygen uptake (Vo2) appears to represent energetic processes in contracting muscle, electromyographic evidence tends not to support this. The present study assessed normalized integrated electromyographic (NIEMG) activity in eight muscles that act about the hip, knee and ankle during 8 min of moderate (ventilatory threshold) cycling in six male cyclists. (Vo2) was measured breath by breath during four repeated trials at each of the two intensities. Moderate and very heavy exercise followed a 4-min period of light exercise (50 W). During moderate exercise the slow (Vo2) phase was absent and NIEMG in all muscles did not increase after the first minute of exercise. During very heavy exercise, the slow phase emerged (time delay=58 ± 16 s) and increased progressively (time constant=120 ± 35 s) to an amplitude (0.83 ± 0.16 L/min) that was approximately 21% of the total (Vo2) response. This slow (Vo2) phase coincided with a significant increase in NIEMG in most muscles, and differences in NIEMG activities between the two intensities revealed "slow" muscle activation profiles that differed between muscles in terms of the onset, amplitude and shape of these profiles. This supports the hypothesis that the slow (Vo2) phase is a function of these different slow muscle activation profiles.

A randomised controlled trial of a tele-based lifestyle intervention for colorectal cancer survivors ('CanChange') : Study protocol

Background Colorectal cancer survivors may suffer from a range of ongoing psychosocial and physical problems that negatively impact on quality of life. This paper presents the study protocol for a novel telephone-delivered intervention to improve lifestyle factors and health outcomes for colorectal cancer survivors. Methods/Design Approximately 350 recently diagnosed colorectal cancer survivors will be recruited through the Queensland Cancer Registry and randomised to the intervention or control condition. The intervention focuses on symptom management, lifestyle and psychosocial support to assist participants to make improvements in lifestyle factors (physical activity, healthy diet, weight management, and smoking cessation) and health outcomes. Participants will receive up to 11 telephone-delivered sessions over a 6 month period from a qualified health professional or 'health coach'. Data collection will occur at baseline (Time 1), post-intervention or six months follow-up (Time 2), and at 12 months follow-up for longer term effects (Time 3). Primary outcome measures will include physical activity, cancer-related fatigue and quality of life. A cost-effective analysis of the costs and outcomes for survivors in the intervention and control conditions will be conducted from the perspective of health care costs to the government. Discussion The study will provide valuable information about an innovative intervention to improve lifestyle factors and health outcomes for colorectal cancer survivors.

Predicting effects of monotony on driver’s vigilance

Monotony has been identified as a contributing factor to road crashes. Drivers’ ability to react to unpredictable events deteriorates when exposed to highly predictable and uneventful driving tasks, such as driving on Australian rural roads, many of which are monotonous by nature. Highway design in particular attempts to reduce the driver’s task to a merely lane-keeping one. Such a task provides little stimulation and is monotonous, thus affecting the driver’s attention which is no longer directed towards the road. Inattention contributes to crashes, especially for professional drivers. Monotony has been studied mainly from the endogenous perspective (for instance through sleep deprivation) without taking into account the influence of the task itself (repetitiveness) or the surrounding environment. The aim and novelty of this thesis is to develop a methodology (mathematical framework) able to predict driver lapses of vigilance under monotonous environments in real time, using endogenous and exogenous data collected from the driver, the vehicle and the environment. Existing approaches have tended to neglect the specificity of task monotony, leaving the question of the existence of a “monotonous state” unanswered. Furthermore the issue of detecting vigilance decrement before it occurs (predictions) has not been investigated in the literature, let alone in real time. A multidisciplinary approach is necessary to explain how vigilance evolves in monotonous conditions. Such an approach needs to draw on psychology, physiology, road safety, computer science and mathematics. The systemic approach proposed in this study is unique with its predictive dimension and allows us to define, in real time, the impacts of monotony on the driver’s ability to drive. Such methodology is based on mathematical models integrating data available in vehicles to the vigilance state of the driver during a monotonous driving task in various environments. The model integrates different data measuring driver’s endogenous and exogenous factors (related to the driver, the vehicle and the surrounding environment). Electroencephalography (EEG) is used to measure driver vigilance since it has been shown to be the most reliable and real time methodology to assess vigilance level. There are a variety of mathematical models suitable to provide a framework for predictions however, to find the most accurate model, a collection of mathematical models were trained in this thesis and the most reliable was found. The methodology developed in this research is first applied to a theoretically sound measure of sustained attention called Sustained Attention Response to Task (SART) as adapted by Michael (2010), Michael and Meuter (2006, 2007). This experiment induced impairments due to monotony during a vigilance task. Analyses performed in this thesis confirm and extend findings from Michael (2010) that monotony leads to an important vigilance impairment independent of fatigue. This thesis is also the first to show that monotony changes the dynamics of vigilance evolution and tends to create a “monotonous state” characterised by reduced vigilance. Personality traits such as being a low sensation seeker can mitigate this vigilance decrement. It is also evident that lapses in vigilance can be predicted accurately with Bayesian modelling and Neural Networks. This framework was then applied to the driving task by designing a simulated monotonous driving task. The design of such task requires multidisciplinary knowledge and involved psychologist Rebecca Michael. Monotony was varied through both the road design and the road environment variables. This experiment demonstrated that road monotony can lead to driving impairment. Particularly monotonous road scenery was shown to have the most impact compared to monotonous road design. Next, this study identified a variety of surrogate measures that are correlated with vigilance levels obtained from the EEG. Such vigilance states can be predicted with these surrogate measures. This means that vigilance decrement can be detected in a car without the use of an EEG device. Amongst the different mathematical models tested in this thesis, only Neural Networks predicted the vigilance levels accurately. The results of both these experiments provide valuable information about the methodology to predict vigilance decrement. Such an issue is quite complex and requires modelling that can adapt to highly inter-individual differences. Only Neural Networks proved accurate in both studies, suggesting that these models are the most likely to be accurate when used on real roads or for further research on vigilance modelling. This research provides a better understanding of the driving task under monotonous conditions. Results demonstrate that mathematical modelling can be used to determine the driver’s vigilance state when driving using surrogate measures identified during this study. This research has opened up avenues for future research and could result in the development of an in-vehicle device predicting driver vigilance decrement. Such a device could contribute to a reduction in crashes and therefore improve road safety.

Structural health monitoring in Australia

Structural Health Monitoring (SHM) is defined as the use of on-structure sensing system to monitor the performance of the structure and evaluate its health state. Recent bridge failures, such as the collapses of the 1-35W Highway Bridge in USA, the collapse of the Can Tho Bridge in Vietnam and the Xijiang River Bridge in the Mainland China, all of which happened in the year 2007, have alerted the importance of structural health monitoring. This book presents a background of SHM technologies together with its latest development and successful applications. It is a book launched to celebrate the establishment of the Australian Network of Structural Health Monitoring (ANSHM). The network comprising leading SHM experts in Australia promotes and advances SHM research, application, education and development in Australia.

Structural health monitoring for long span bridges : Hong Kong experience and continuing onto Australia

Structural health monitoring has been accepted as a justified effort for long-span bridges, which are critical to a region's economic vitality. As the most heavily instrumented bridge project in the world, WASHMS - Wind And Structural Health Monitoring System has been developed and installed on the cable-supported bridges in Hong Kong (Wong and Ni 2009a). This chapter aims to share some of the experience gained through the operations and studies on the application of WASHMS. It is concluded that Structural Health Monitoring should be composed of two main components: Structural Performance Monitoring (SPM) and Structural Safety Evaluation (SSE). As an example to illustrate how the WASHMS could be used for structural performance monitoring, the layout of the sensory system installed on the Tsing Ma Bridge is briefly described. To demonstrate the two broad approaches of structural safety evaluation - Structural Health Assessment and Damage Detection, three examples in the application of SHM information are presented. These three examples can be considered as pioneer works for the research and development of the structural diagnosis and prognosis tools required by the structural health monitoring for monitoring and evaluation applications.

Renewing concrete sleepers : how long can they last?

The paper explores the way in which the life of concrete sleepers can be dramatically affected by two important factors, namely impact forces and fatigue cycles. Drawing on the very limited experimental and field data currently available about these two factors, the paper describes detailed simulations of sleepers in a heavy haul track in Queensland Australia over a period of 100 years. The simulation uses real wheel/rail impact force records from that track, together with data on static bending tests of similar sleepers and preliminary information on their impact vs static strength. The simulations suggest that despite successful performance over many decades, large unplanned replacement costs could be imminent, especially considering the increasingly demanding operational conditions sleepers have sustained over their life. The paper also discusses the key factors track owners need to consider in attempting to plan for these developments.

Exercise and cancer rehabilitation : a systematic review

Introduction: Cancer is increasingly being viewed as a chronic illness requiring long-term management, and there is a growing need for evidence-based rehabilitation interventions for cancer survivors. Previous reviews have evaluated the benefits of exercise interventions for patients undergoing cancer treatment and long-term survivors, but none have investigated the role of exercise during cancer rehabilitation, the period immediately following cancer treatment completion. This systematic review summarises the literature on the health effects of exercise during cancer rehabilitation and evaluates the methodological rigour of studies in this area to date.----------- Methods: Relevant studies were identified through a systematic search of PubMed and Embase to April 2009. Data on study design, recruitment strategy, participants, exercise intervention, adherence rates, and outcomes were extracted. Methodological rigour was assessed using a structured rating system.---------- Results: Ten studies were included. Breast cancer patients were the predominate patient group represented. Most interventions were aerobic or resistance-training exercise programmes, and exercise type, frequency, duration and intensity varied across studies. Improvements in physical functioning, strength, physical activity levels, quality of life, fatigue, immune function, haemoglobin concentrations, potential markers of recurrence, and body composition were reported. However, all studies were limited by incomplete reporting and methodological limitations.---------- Conclusions: Although the methodological limitations of studies in this new field must be acknowledged, initial evidence indicates that exercise is feasible and may provide physiological and psychological benefits for cancer survivors during the rehabilitation period. Future studies with rigorous study designs are now required to advance the field.

Colorectal cancer survivors’ exercise experiences and preferences : qualitative findings from an exercise rehabilitation programme immediately after chemotherapy

Little is known about cancer survivors’ experiences with and preferences for exercise programmes offered during rehabilitation (immediately after cancer treatment). This study documented colorectal cancer survivors’ experiences in an exercise rehabilitation programme and their preferences for programme content and delivery. At the completion of 12-weeks of supervised exercise, 10 participants took part in one-on-one semi-structured interviews. Data from these interviews were coded, and themes were identified using qualitative software. Key findings were that most participants experienced improvements in treatment symptoms, including reduced fatigue and increased energy and confidence to do activities of daily living. They also reported that interactions with the exercise trainer and a flexible programme delivery were important aspects of the intervention. Most participants reported that they preferred having a choice of exercise, starting to exercise within a month after completing treatment, having supervision and maintaining a one-on-one format. Frustrations included scheduling conflicts and a lack of a transition out of the programme. The findings indicate that colorectal cancers experience benefits from exercise offered immediately after treatment and prefer individual attention from exercise staff. They further indicate directions for the implementation of future exercise programmes with this population.

Intradialytic exercise : a feasibility study

Background: Exercise is known to improve mental and physical functioning and to improve quality of life. The obstacles faced by individuals with chronic kidney disease on maintenance haemodialysis include increased levels of fatigue, decreased motivation, and the inability to schedule exercise around daily activities and dialysis schedules. Aim: This pilot study was undertaken to determine the feasibility and potential efficacy of an individually-tailored exercise program for in-centre haemodialysis patients. Method: A 16 week program was designed and evaluated in relation to changes in physical capacity, the extent of exercise undertaken, and quality of life indicators. Results and Conclusion: The resultant recommendations regarding the level of motivational support, the time and physical requirements in implementing an exercise program will provide useful information for others embarking on similar studies.

Visual assessment of pedestrian crashes

Of the numerous factors that play a role in fatal pedestrian collisions, the time of day, day of the week, and time of year can be significant determinants. More than 60% of all pedestrian collisions in 2007 occurred at night, despite the presumed decrease in both pedestrian and automobile exposure during the night. Although this trend is partially explained by factors such as fatigue and alcohol consumption, prior analysis of the Fatality Analysis Reporting System database suggests that pedestrian fatalities increase as light decreases after controlling for other factors. This study applies graphical cross-tabulation, a novel visual assessment approach, to explore the relationships among collision variables. The results reveal that twilight and the first hour of darkness typically observe the greatest frequency of pedestrian fatal collisions. These hours are not necessarily the most risky on a per mile travelled basis, however, because pedestrian volumes are often still high. Additional analysis is needed to quantify the extent to which pedestrian exposure (walking/crossing activity) in these time periods plays a role in pedestrian crash involvement. Weekly patterns of pedestrian fatal collisions vary by time of year due to the seasonal changes in sunset time. In December, collisions are concentrated around twilight and the first hour of darkness throughout the week while, in June, collisions are most heavily concentrated around twilight and the first hours of darkness on Friday and Saturday. Friday and Saturday nights in June may be the most dangerous times for pedestrians. Knowing when pedestrian risk is highest is critically important for formulating effective mitigation strategies and for efficiently investing safety funds. This applied visual approach is a helpful tool for researchers intending to communicate with policy-makers and to identify relationships that can then be tested with more sophisticated statistical tools.

The role of nature-based experiences in the development and maintenance of wellness

Wellness is now seen as central to redefining the National Health agenda. There is growing evidence that contact with nature and physical activity in nature has considerable positive effects on human health. At the most basic level humanity is reliant on the natural world for resources such as air and water. However, a growing body of research is finding that beyond this fundamental relationship exposure to the non-human natural world can also positively enhance perceptions of physiological, emotional, psychological and spiritual health in ways that cannot be satisfied by alternate means. Theoretical explanations for this have posited that non-human nature might 1) restore mental fatigue, 2) trigger deep reflections, 3) provide an opportunity for nurturing and 4) rekindle innate connections. In this paper the authors show how human wellness is strongly connected to their relationship with the natural world. This paper points to how non-human nature could be better utilised for enhancing human health and wellness.

Down the rabbit hole and through the looking glass: A conception of information seeking and searching through a diary study.

Information behaviour (IB) is an area within Library and Information Science that studies the totality of human behaviour in relation to information, both active and passive, along with the explicit and the tacit mental states related to information. This study reports on a recently completed dissertation research that integrates the different models of information behaviours using a diary study where 34 participants maintained a daily journal for two weeks through a web log or paper diary. This resulted in thick descriptions of IB, which were manually analysed using the Grounded Theory method of inquiry, and then cross-referenced through both text-analysis and statistical analysis programs. Among the many key findings of this study, one is the focus this paper: how participants express their feelings of the information seeking process and their mental and affective states related specifically to the sense-making component which co-occurs with almost every other aspect of information behaviour. The paper title – Down the Rabbit Hole and Through the Looking Glass – refers to an observation that some of the participants made in their journals when they searched for, or avoided information, and wrote that they felt like they have fallen into a rabbit hole where nothing made sense, and reported both positive feelings of surprise and amazement, and negative feelings of confusion, puzzlement, apprehensiveness, frustration, stress, ambiguity, and fatigue. The study situates this sense-making aspects of IB within an overarching model of information behaviour that includes IB concepts like monitoring information, encountering information, information seeking and searching, flow, multitasking, information grounds, information horizons, and more, and proposes an integrated model of information behaviour illuminating how these different concepts are interleaved and inter-connected with each other, along with it's implications for information services.