International differences in management of physical activity data: Can they explain some of the difference in prevalence estimates?

Background: National physical activity data suggest that there is a considerable difference in physical activity levels of US and Australian adults. Although different surveys (Active Australia and BRFSS) are used, the questions are similar. Different protocols, however, are used to estimate “activity” from the data collected. The primary aim of this study was to assess whether the 2 approaches to the management of PA data could explain some of the difference in prevalence estimates derived from the two national surveys. Methods: Secondary data analysis of the most recent AA survey (N = 2987). Results: 15% of the sample was defined as “active” using Australian criteria but as “inactive” using the BRFSS protocol, even though weekly energy expenditure was commensurate with meeting current guidelines. Younger respondents (age < 45 y) were more likely to be “misclassified” using the BRFSS criteria. Conclusions: The prevalence of activity in Australia and the US appears to be more similar than we had previously thought.

Living a life with a physical impairment in Taiwan : "It is more than just the impairment"

This thesis is concerned with understanding what it is like to live with a physical impairment in Taiwan. Constructionism was used as the epistemological stance to guide the study and Heideggerian interpretive phenomenology was used as the theoretical perspective. Information was gained through a series of in-depth interviews with seven Taiwanese adults with a physical impairment living in the community. They were recruited from Yunlin and Tainan Counties in Taiwan. Study participants were seen as research partners who had expertise in understanding disability, and the researcher was seen as a learner. Grounded theory principles were used to develop the theory "it is more than just the impairment" from the information provided by the participants. According to their descriptions of how they lived their lives, participants are grouped into three clusters. These are ‘fortress ladies’, ‘social networkers’ and ‘the mind man’. The grounded theory developed portrays their lives, providing a vivid picture of living a life with a physical impairment in Taiwan. The study’s findings contribute to three main areas. First, as an occupational therapist and with my growing understanding of disability learned from the study participants, I recognize the agency of people with an impairment and their expertise in disability. Thus, I argue the need for health professionals to build alliances with them, and suggest ways to achieve such a relationship. Second, I propose the developed conceptual framework is suitable for exploring lived experience in other research areas; I discuss the implications of the subtle interactions between impaired people’s body and mind; I also present three impressive lived experiences provided by study participants as exemplars of the findings, and these form the foundation for discussion. Finally, the development of "it is more than just the impairment" provides a basis from which to theorize disability in a more holistic way.

Power-law viscous materials for analogue experiments: New data on the rheology of highly-filled silicone polymers

The selection of appropriate analogue materials is a central consideration in the design of realistic physical models. We investigate the rheology of highly-filled silicone polymers in order to find materials with a power-law strain-rate softening rheology suitable for modelling rock deformation by dislocation creep and report the rheological properties of the materials as functions of the filler content. The mixtures exhibit strain-rate softening behaviour but with increasing amounts of filler become strain-dependent. For the strain-independent viscous materials, flow laws are presented while for strain-dependent materials the relative importance of strain and strain rate softening/hardening is reported. If the stress or strain rate is above a threshold value some highly-filled silicone polymers may be considered linear visco-elastic (strain independent) and power-law strain-rate softening. The power-law exponent can be raised from 1 to ~3 by using mixtures of high-viscosity silicone and plasticine. However, the need for high shear strain rates to obtain the power-law rheology imposes some restrictions on the usage of such materials for geodynamic modelling. Two simple shear experiments are presented that use Newtonian and power-law strain-rate softening materials. The results demonstrate how materials with power-law rheology result in better strain localization in analogue experiments.

The preferences of private equity investors in selecting target acquisitions : an international investigation

This study investigates the characteristics and attributes that private equity investors prefer when selecting target acquisitions. These characteristics are examined against a matched sample of firms subject to corporate acquisitions via tender/merger offer during 2000-2009, across seven countries: Australia, Canada, the United Kingdom, the USA, France, Germany and Sweden. We show that firm-specific characteristics are more influential in target selection than external or institutional variables. In particular, private equity targets exhibit lower stock volatility and long-term growth prospects, are larger, and have greater abnormal operating income relative to tender/merger offer target firms. Further, private equity bidders exhibit 'home bias', implying that familiarity motivates target selection. Institutional factors remain largely insignificant across all tests.

A longitudinal study of health-related quality of life, fatigue and physical activity in chronic kidney disease patients

This study assessed the health-related quality of life (HRQoL), fatigue and physical activity levels of 28 persons with chronic kidney disease (CKD) on initial administration of an erythropoietin stimulating agent, and at 3 months, 6 months and 12 months. The sample comprised of 15 females and 13 males whose ages ranged from 31 to 84 years. Physical activity was measured using the Human Activity Profile (HAP): Self-care, Personal/Household work, Entertainment/Social, Independent exercise. Quality of life was measured using the SF-36 which gives scores on physical health (physical functioning, role-physical, bodily pain and general health) and mental health (vitality, social functioning, role-emotional and emotional well-being). Fatigue was measured by the Fatigue Severity Scale (FSS). Across all time points the renal sample engaged in considerably less HAP personal/household work activities and entertainment/social activities compared to healthy adults. The normative sample engaged in three times more independent/exercise activities compared to renal patients. One-way Repeated measures ANOVAs indicated a significant change over time for SF-36 scales of role physical, vitality, emotional well-being and overall mental health. There was a significant difference in fatigue levels over time [F(3,11) = 3.78, p<.05]. Fatigue was highest at baseline and lowest at 6 months. The more breathlessness the CKD patient reported, the fewer activities undertaken and the greater the reported level of fatigue. There were no significant age differences over time for fatigue or physical activity. Age differences were only found for SF-36 mental health at 3 months (t=-2.41, df=14, p<.05). Those younger than 65 years had lower emotional well-being compared to those aged over 65. Males had poorer physical health compared to females at 12 months. There were no significant gender differences on mental health at any time point. In the management of chronic kidney disease, early detection of a person’s inability to engage in routine activities due to fatigue is necessary. Early detection would enable timely interventions to optimise HRQoL and independent exercise.

Post-match changes in neuromuscular function and the relationship to match demands in amateur rugby league matches

Objectives: The current study investigated the change in neuromuscular contractile properties following competitive rugby league matches and the relationship with physical match demands. Design: Eleven trained, male rugby league players participated in 2–3 amateur, competitive matches (n = 30). Methods: Prior to, immediately (within 15-min) and 2 h post-match, players performed repeated counter-movement jumps (CMJ) followed by isometric tests on the right knee extensors for maximal voluntary contraction (MVC), voluntary activation (VA) and evoked twitch contractile properties of peak twitch force (Pt), rate of torque development (RTD), contraction duration (CD) and relaxation rate (RR). During each match, players wore 1 Hz Global Positioning Satellite devices to record distance and speeds of matches. Further, matches were filmed and underwent notational analysis for number of total body collisions. Results: Total, high-intensity, very-high intensity distances covered and mean speed were 5585 ± 1078 m, 661 ± 265, 216 ± 121 m and 75 ± 14 m min−1, respectively. MVC was significantly reduced immediately and 2 h post-match by 8 ± 11 and 12 ± 13% from pre-match (p < 0.05). Moreover, twitch contractile properties indicated a suppression of Pt, RTD and RR immediately post-match (p < 0.05). However, VA was not significantly altered from pre-match (90 ± 9%), immediately-post (89 ± 9%) or 2 h post (89 ± 8%), (p > 0.05). Correlation analyses indicated that total playing time (r = −0.50) and mean speed (r = −0.40) were moderately associated to the change in post-match MVC, while mean speed (r = 0.35) was moderately associated to VA. Conclusions: The present study highlights the physical demands of competitive amateur rugby league result in interruption of peripheral contractile function, and post-match voluntary torque suppression may be associated with match playing time and mean speeds.

Political selection and the relative age effect

In this paper we present substantial evidence for the existence of a bias in the distribution of births of leading US politicians in favor of those that have been the oldest in their cohort at school. This “relative age effect” has been proven to influence performance at school and in sports,but evidence on its impact on people’s vocational success has been rare. We find a marked break in the density of birthdate of politicians using a maximum likelihood test and McCrary’s (2008) nonparametric test. We conjecture that being relatively old in a peer group may create long term advantages which can create a significant role in the ability to succeed in a highly competitive environment like the race for top political offices in the USA. The magnitude of the effect we estimate is larger than what most other studies on the relative age effect for a broader (adult) population find, but is in general in line with studies that look at populations in high-competition environments.