The influence of age and gender on triclosan concentrations in Australian human blood serum

The bactericide triclosan has found wide-spread use in e.g. soaps, deodorants and toothpastes. Recent in vitro and in vivo studies indicate that triclosan might exert adverse effects in humans. Triclosan has previously been shown to be present in human plasma and milk at concentrations that are well correlated to the use of personal care products containing triclosan. In this study we investigated the influence of age, gender, and the region of residence on triclosan concentrations in pooled samples of Australian human blood serum. The results showed no influence of region of residence on the concentrations of triclosan. There was a small but significant influence of age and gender on the serum triclosan concentrations, which were higher in males than in females, and highest in the group of 31–45 year old males and females. However, overall there was a lack of pronounced differences in the triclosan concentrations within the dataset, which suggests that the exposure to triclosan among different groups of the Australian population is relatively homogenous. A selection of the dataset was compared with previous measurements of triclosan concentrations in human plasma from Sweden, where the use of triclosan is expected to be low due to consumer advisories. The triclosan concentrations were a factor of 2 higher in Australian serum than in Swedish plasma.

The efficacy of the Sortino ratio and other benchmarked performance measures under skewed return distributions

This paper will investigate the suitability of existing performance measures under the assumption of a clearly defined benchmark. A range of measures are examined including the Sortino Ratio, the Sharpe Selection ratio (SSR), the Student’s t-test and a decay rate measure. A simulation study is used to assess the power and bias of these measures based on variations in sample size and mean performance of two simulated funds. The Sortino Ratio is found to be the superior performance measure exhibiting more power and less bias than the SSR when the distribution of excess returns are skewed.

An empirical investigation of the level effect in Australian interest rates

An extensive literature examines the dynamics of interest rates, with particular attention given to the positive relationship between interest-rate volatility and the level of interest rates—the so-called level effect. This paper examines the interaction between the estimated level effect and competing parameterisations of interest-rate volatility for the Australian yield curve. We adopt a new methodology that estimates elasticity in a multivariate setting that explicitly accommodates the correlations that exist between various yield factors. Results show that significant correlations exist between the residuals of yield factors and that such correlations do indeed impact on model estimates. Within the multivariate setting, the level of the short rate is shown to be a crucial determinant of the conditional volatility of all three yield factors. Measures of model fit suggest that, in addition to the usual level effect, the incorporation of GARCH effects and possible regime shifts is important

The distribution of the sample minimum-variance frontier

In this paper, we present a finite sample analysis of the sample minimum-variance frontier under the assumption that the returns are independent and multivariate normally distributed. We show that the sample minimum-variance frontier is a highly biased estimator of the population frontier, and we propose an improved estimator of the population frontier. In addition, we provide the exact distribution of the out-of-sample mean and variance of sample minimum-variance portfolios. This allows us to understand the impact of estimation error on the performance of in-sample optimal portfolios. Key Words: minimum-variance frontier; efficiency set constants; finite sample distribution

Required hours of practice for learner drivers : a comparison between two Australian jurisdictions

Problem: This study considers whether requiring learner drivers to complete a set number of hours while on a learner licence affects the amount of hours of supervised practice that they undertake. It compares the amount of practice that learners in Queensland and New South Wales report undertaking. At the time the study was conducted, learner drivers in New South Wales were required to complete 50 hours of supervised practice while those from Queensland were not. Method: Participants were approached outside driver licensing centres after they had just completed their practical driving test to obtain their provisional (intermediate) licence. Those agreeing to participate were interviewed over the phone later and asked a range of questions to obtain information including socio-demographic details and amount of supervised practice completed. Results: There was a significant difference in the amount of practice that learners reported undertaking. Participants from New South Wales reported completing a significantly greater amount of practice (M = 73.3 hours, sd = 29.12 hours) on their learner licence than those from Queensland (M = 64.1 hours, sd = 51.05 hours). However, the distribution of hours of practice among the Queensland participants was bimodal in nature. Participants from Queensland reported either completing much less or much more practice than the New South Wales average. Summary: While it appears that the requirement that learner drivers complete a set number of hours may increase the average amount of hours of practice obtained, it may also serve to discourage drivers from obtaining additional practice, over and above the required hours. Impact on Industry: The results of this study suggest that the implications of requiring learner drivers to complete a set number of hours of supervised practice are complex. In some cases, policy makers may inadvertently limit the amount of hours learners obtain to the mandated amount rather than encouraging them to obtain as much practice as possible.

Land use at privatized Australian airports : classification and analyses

In recent years the air transport industry has experienced unprecedented growth, driven by strong local and global economies. Whether this growth can continue in the face of anticipated oil crises; international economic forecasts and recent influenza outbreaks is yet to be seen. One thing is certain, airport owners and operators will continue to be faced with challenging environments in which to do business. In response, many airports recognize the value in diversifying their revenue streams through a variety of landside property developments within the airport boundary. In Australia it is the type and intended market of this development that is a point of contention between private airport corporations and their surrounding municipalities. The aim of this preliminary research is to identify and categorize on-airport development occurring at the twenty-two privatized Australian airports which are administered under the Airports Act [1996]. This new knowledge will assist airport and municipal planners in understanding the current extent and category of on-airport land use, allowing them to make better decisions when proposing development both within airport master plans and beyond the airport boundary in local town and municipal plans.

Australian media ethics regime and ethical risk management

Media organizations are simultaneously key elements of an effective democracy and, for the most part, commercial entities seeking success in the market. They play an essential role in the formation of public opinion and the influence on personal choices. Yet most of them are commercial enterprises seeking readers or viewers, advertising, favorable regulatory decisions for their media, and other assets. This creates some intrinsic difficulties and produces some sharp tensions within media ethics. In this article, we examine such tensions—in theory and practice. We then consider the feasibility of introducing an ethics regime to the media industry—a regime that would be effective in a deregulated environment in protecting public interest and social responsibility. In the article, we also outline a rationale and a methodology for the institutionalization of an acceptable and workable media ethics regime that aims to protect the integrity of the industry in a future of undoubtedly increasing commercial pressure.

A pilot randomised control trial of general practitioner and exercise physiologist interventions to reduce primary cardiovascular risk in overweight patients [Abstract]

Aims & Rationale/Objectives: With the knowledge that overweight is a major public health concern in Australia, that a multidisciplinary team approach to the management of lifestyle-related conditions is supported, and that the Australian Government recently recognised the role of the exercise physiologist (EP) in reducing the health burden of disease by their inclusion for reimbursement under the Medicare Plus scheme, this study sought to undertake a pilot RCT to compare GP and EP interventions to reduce primary cardiovascular risk in the overweight general practice population. Methods and Measures: Overweight patients recruited by a convenience sample of GPs were randomised into one of three arms: the control group, or the GP or EP intervention group (in which patients received either five GP or five EP consultations over 24 weeks). Patients had baseline, 12- and 24-week measures of body composition and cardio-respiratory fitness, and completed baseline and end-of-study surveys, fasting lipids and glucose. GPs and EPs completed an end-of-study survey. Results:Sixty-seven patients attended the baseline assessment. Overall retention rate was 67%. Patients were generally satisfied with the effectiveness of the interventions and their weight reduction. Favourable trends in BMI, weight, glucose and exercise levels for GP and EP intervention groups and in physical activity levels for all groups Conclusions: This study supports the feasibility of a RCT of GP and EP interventions for decreasing primary cardiovascular risk in the overweight general practice population.

Blogs, wikis and podcasts : collaborative knowledge building tools in a design and technology course

Design and Technology has become an important part of the school curriculum. In Queensland, Australia, Technology (which encompasses Design) is one of the Key Learning Areas (KLAs) for students in the first ten years of schooling. This KLA adopts a student-centred, hands-on constructivist approach to teaching and learning. The ability to conceptualise and implement appropriate learning experiences, however, has been a challenge for some early career teachers. This paper describes how Design and Technology is being taught to pre-service primary teachers at an Australian University through their involvement in a range of authentic problem-solving activities supported by social learning tools such as wikis and blogs. An interview with a sample from this group (N=5) provides an insight into how these social software tools enhanced their knowledge and learning. This paper will describe how these social learning tools impact on the agency of learning.