The role of social support in protecting mental health when employed and unemployed: a longitudinal fixed-effects analysis using 12 annual waves of the HILDA cohort

Perceived social support is associated with overall better mental health. There is also evidence that unemployed workers with higher social support cope better psychologically than those without such support. However, there has been limited research about the effect of social support among people who have experienced both unemployment and employment. We assessed this topic using 12 years of annually collected cohort data. The sample included 3190 people who had experienced both unemployment and employment. We used longitudinal fixed-effects modelling to investigate within-person changes in mental health comparing the role of social support when a person was unemployed to when they were employed. Compared to when a person reported low social support, a change to medium (6.35, 95% 5.66 to 7.04, p < 0.001) or high social support (11.58, 95%, 95% CI 10.81 to 12.36, p < 0.001) was associated with a large increase in mental health (measured on an 100 point scale, with higher scores representing better mental health). When a person was unemployed but had high levels of social support, their mental health was 2.89 points (95% CI 1.67 to 4.11, p < 0.001) higher than when they were employed but had lower social support. The buffering effect of social support was confirmed in stratified analysis. There was a strong direct effect of social support on mental health. The magnitude of these differences could be considered clinically meaningful. Our results also suggest that social support has a significant buffering effect on mental health when a person is unemployed.

Improving the precision of the accumulated oxygen deficit using VO2-power regression points from below and above the lactate threshold

The accumulated oxygen deficit (AOD) method assumes a linear VO₂-power relationship for exercise intensities increasing from below the lactate threshold (BLT) to above the lactate threshold (ALT). Factors that were likely to effect the linearity of the VO₂-power regression and the precision of the estimated total energy demand (ETED) were investigated. These included the slow component of VO₂ kinetics (SC), a forced resting y-intercept and exercise intensities BLT and ALT. Criteria for linearity and precision included the Pearson correlation coefficient (PCC) of the VO₂-power relationship, the length of the 95% confidence interval (95% CI) of the ETED and the standard error of the predicted value (SEP), respectively. Eight trained male and one trained female triathlete completed the required cycling tests to establish the AOD when pedalling at 80 rev/min. The influence of the SC on the linear extrapolation of the ETED was reduced by measuring VO₂ after three min of exercise. Measuring VO₂ at this time provided a new linear extrapolation method consisting of ten regression points spread evenly from BLT and ALT. This method produced an ETED with increased precision compared to using regression equations developed from intensities BLT with no forced y-intercept value; (95%CI (L), 0.70±0.26 versus 1.85±1.10, P<0.01; SEP(L/Watt), 0.07±0.02 versus 0.28±0.17; P<0.01). Including a forced y-intercept value with five regression points either BLT or ALT increased the precision of estimating the total energy demand to the same level as when using 10 regression points, (5 points BLT + y-intercept versus 5 points ALT + y-intercept versus 10 points; 95%CI(l), 0.61±0.32, 0.87±0.40, 0.70±0.26; SEP(L/Watt), 0.07±0.03, 0.08±0.04, 0.07±0.02; p>0.05). The VO₂-power regression can be designed using a reduced number of regression points... ABSTRACT FROM AUTHOR

Measuring health in a vacuum: examining the disability weight of the DALY

The Disability Adjusted Life Year (DALY) is a widely used summary measure of population health combining years of life lost due to mortality and years of healthy life lost due to disability. A feature of the DALY is that, in the assessment of morbidity, each health condition is associated with a disability weight. The disability weight lies on a scale between 0 (indicating the health condition is equivalent to full health) and 1 (indicating the health condition is equivalent to death). The disability weight associated with each health condition is currently fixed across all social, cultural and environmental contexts. Thus blindness in the United Kingdom has the same disability weight as blindness in Niger in spite of structural interventions in the UK that make the disability less severe than in Niger. Although the fixed disability weight is defended on grounds that it supports a strongly egalitarian flavour in the DALY, we argue that the lack of consideration of realistic contexts results in a measure that will underestimate the burden associated with morbidity in disadvantaged populations and overestimate the burden in advantaged populations. There is, consequently, a loss of information on possible non-clinical points of intervention. Disaggregated estimates of the burden of disease such as those in the World Health Report 2000 should be interpreted with caution.

Drying front in a sloping aquifier: nonlinear effects

The profiles for the water table height h(x, t) in a shallow sloping aquifer are reexamined with a solution of the nonlinear Boussinesq equation. We demonstrate that the previous anomaly first reported by Brutsaert [1994] that the point at which the water table h first becomes zero at x = L at time t = t c remains fixed at this point for all times t > t c is actually a result of the linearization of the Boussinesq equation and not, as previously suggested [ Brutsaert, 1994 ; Verhoest and Troch, 2000 ], a result of the Dupuit assumption. Rather, by examination of the nonlinear Boussinesq equation the drying front, i.e., the point x f at which h is zero for times t ≥ t c , actually recedes downslope as physically expected. This points out that the linear Boussinesq equation should be used carefully when a zero depth is obtained as the concept of an “average” depth loses meaning at that time.

Evaluation of fixed sample-size plans for Plutella xylostella (Lepidoptera: Plutellidae) on broccoli crops in Australia

Fixed sample-size plans for monitoring Plutella xylostella (L.) (Lepidoptera: Plutellidae) on broccoli and other Brassica vegetable crops are popular in Australia for their simplicity and ease of application. But the sample sizes used are often small, ≈10–25 plants per crop, and it may be that they fail to provide sufficient information upon which to base pest control decisions. We tested the performance of seven fixed sample-size plans (10, 15, 20, 30, 35, 40, and 45 plants) by resampling a large data set on P. xylostella in commercial broccoli crops. For each sample size, enumerative and presence-absence plans were assessed. The precision of the plans was assessed in terms of the ratio of the standard error to the mean; and at least 45 and 35 samples were necessary for the enumerative and presence-absence plans, respectively, to attain the generally accepted benchmark of ≤0.3. Sample sizes of 10–20 were highly imprecise. We also assessed the consequences of classifications based on action thresholds (ATs) of 0.2 and 0.8 larvae per plant for the enumerative case, and 0.15 and 0.45 proportion of plants of infested for the presence-absence case. Operating characteristic curves and investigations of the frequency of correct decisions suggest improvements in the performance of plans with increased sample size. In both the enumerative and presence-absence cases, the proportion of incorrect decisions was much higher for the lower of the two ATs assessed, and type II errors (i.e., failure to suggest pest control upon the AT is exceeded) generally accounted for the majority of this error. Type II errors are the most significant from a producer’s standpoint. Further consideration is necessary to determine what is an acceptable type II error rate.

Overweight and obesity prevalence in children based on 6- or 12- month IOTF cut-points: does interval size matter?

The International Obesity Taskforce (IOTF) recommends using age- and gender-specific body mass index (BMI) cut-points for defining the prevalence of overweight and obesity in children. These are given in both 6- and 12-month age intervals. Since the BMI-for-age curves are nonlinear, a degree of bias will be introduced when age intervals are wide. We aimed to quantify this bias in prevalence estimates in 2178 Australian children aged 4-12 years using 12- versus 6-month age intervals. Using the 12-month interval, the prevalence of overweight and obesity was underestimated by 1.4% compared to the 6-month interval estimates; however, this was age-dependent. It overestimated prevalence for 4-year olds, but underestimated it for older ages by up to 2.6%. Overweight prevalence was generally affected more than obesity prevalence. The use of different age intervals for IOTF cut-points introduces a small but systematic bias in prevalence estimates of overweight and obesity.

Bourdieu`s reflexive sociology and `spaces of points of view`: whose reflexivity, which perspective?

This paper considers Bourdieu's concepts of perspectivism and reflexivity, looking particularly at how he develops arguments about these in his recent work, The Weight of the World (1999) and Pascalian Meditations (2000b). We explicate Bourdieu's distinctive purposes and deployment of these terms and approaches, and discuss how this compares with related methodological and theoretical approaches currently found in social and feminist theory. We begin by considering three main ways in which 'reflexivity' is deployed in current sociological writing, distinguishing between reflexive sociology and a sociology of reflexivity. This is followed by a discussion of the main aspects of Bourdieu's approach to 'reflexive sociology' and its relation to his concepts of social field, perspectivism and spaces of point of view. He argues that we need to interrogate the idea of a single 'perspective' and account especially for the particularity and influence of the 'scholastic' point of view. He characterizes this latter point of view as unaware of its own historicity and as largely concerned with contemplation and with treating ideas primarily as abstractions (Bourdieu, 2000b). Bourdieu's intervention is to argue, as he has throughout his work, for a more reflexive account of one's location and habitus, and for sustained engagement with ideas and social issues as practical problems. Bourdieu exhorts researchers to work with 'multiple perspectives' (Bourdieu et al., 1999, p. 3), the various competing 'spaces of points of view', without collapsing into subjectivism or relativism. We then consider recent feminist engagements with and critiques of Bourdieu's notion of reflexivity and chart some of the main points of contention regarding its relevance and conceptual potential for theorizing gender identities and transformations in current times. We conclude with a brief outline of how we are working with a reflexive sociological approach in a cross-generational study of young women in difficult circumstances, 'on the margins' of education and work.

Young women with type 1 diabetes' management of turning points and transitions

The authors used grounded theory to explore and develop a substantive theory to explain how 20 young women with type 1 diabetes managed their lives when facing turning points and undergoing transitions. The women experienced a basic social problem: being in the grip of blood glucose levels (BGLs), which consisted of three categories: (a) the impact of being susceptible to fluctuating BGLs, (b) the responses of other people to the individual woman’s diabetes, and (c) the impact of the individual women’s diabetes on other people’s lives. The women used a basic social process to overcome the basic social problem by creating stability, which involved using three interconnected subprocesses: forming meaningful
relationships, enhancing attentiveness to blood glucose levels, and putting things in perspective. Insights into the processes and strategies used by the women have important implications for provision of care and service delivery.

Tipping points in online-mediated learning environments

Teacher/Student engagement enriches learning experiences beyond the specifics of communicated information by encouraging connectivity and the fostering of learning communities. This paper is an analysis of student engagement in a postgraduate online-mediated learning environment, and considers how engagement may be an important factor in building communities of learning in conjunction with improved learning outcomes. This paper is informed by the conceptual framework for effective e-learning outlined by Garrison and Anderson (2003) as necessary for higher order knowledge building by students as part of skills development for participation in knowledge economies. Data collected through a pilot study infers that a correlation exists between the development of small groups of significantly contributing students within wider online student cohorts and the learning outcomes of all students within the cohort. The findings indicate that a number of small events have increased student engagement and motivation, and resulted in improved learning outcomes.

Fixed and floating charges : the latest conflicting law and how to address the gaps

Can book debts be subject to a fixed charge? This question was considered by the House of Lords in National Westminster Bank v. Spectrum Plus Limited [2005] UKHL 41 where the full House was against the idea of a fixed charge on book debts and insisted that only a floating charge had been created. The law in this area is still vague and uncertain in Australia. This paper argues that the financiers and the companies should be given the freedom to decide how they wish to structure their charge documents. The paper sets out to argue that, in respect to the use of book debts as security for a loan, the only way for both the financiers and the companies to do business is to create a sustained workable fixed charge or even multiple fixed and floating charge on book debts. The author explains how this could be possible and how the proposed model would not deny the statutory priority rights of the preferential creditors.