The Effect of Education on Smoking Behavior: New Evidence from Smoking Durations of a Sample of Twins

This paper analyses the effect of education on starting and quitting smoking, using longitudinal data of Australian twins. The endogeneity of education, censoring of smoking durations and the timing of starting smoking versus that of completion of education are taken into account by the flexible Mixed Proportional Hazard specification. Unobserved effects are assumed to be twin specific and possibly correlated with completed education years. We find that one additional year of education reduces the duration of smoking with 9 months but has no effect on the decision to start smoking.education, duration models, smoking

Shape: A 3D Modeling Tool for Astrophysics

We present a flexible interactive 3D morpho-kinematical modeling application for astrophysics. Compared to other systems, our application reduces the restrictions on the physical assumptions, data type and amount that is required for a reconstruction of an object's morphology. It is one of the first publicly available tools to apply interactive graphics to astrophysical modeling. The tool allows astrophysicists to provide a-priori knowledge about the object by interactively defining 3D structural elements. By direct comparison of model prediction with observational data, model parameters can then be automatically optimized to fit the observation. The tool has already been successfully used in a number of astrophysical research projects.Comment: 13 pages, 11 figures, accepted for publication in the "IEEE Transactions on Visualization and Computer Graphics

The Effect of Childhood Conduct Disorder on Human Capital

This paper estimates the longer-term effects of childhood conduct disorder on human capital accumulation and violent and criminal behaviour later in life using data of Australian twins. We measure conduct disorder with a rich set of indicators based on diagnostic criteria from psychiatry. Using ordinary least squares (OLS) and twin fixed effects (FE) estimation approaches, we find that early (pre-18) conduct disorder problems significantly affect both human capital accumulation and violent and criminal behaviour over the life course. In addition, we find that conduct disorder is more deleterious if these behaviours occur earlier in life.conduct disorder, human capital, twins

Organisational ethnography and religious organisations: The case of Quaker decision-making

How should we study the management practices of religious organizations to do justice to their distinctive religious motivations and traditions? In this paper, we articulate how a specific research approach – organizational ethnography – may enable a deeper understanding of religious and/or spiritual organizational practice. We approach our methodological research questions by engaging with the literature on the distinctive decisionmaking practices of the Religious Society of Friends (Quakers), commonly known as the Quaker business method. Having shown that the Quaker business method destabilizes a simple binary between ‘insider’ and ‘outsider’ and between believers and non-believers, we bring the theory and practice of organizational ethnography into conversation with Quaker accounts of decision-making. We conclude with pathways for future research in the space this destabilization creates

Anomalous spin-splitting of two-dimensional electrons in an AlAs Quantum Well

We measure the effective Lande g-factor of high-mobility two-dimensional electrons in a modulation-doped AlAs quantum well by tilting the sample in a magnetic field and monitoring the evolution of the magnetoresistance oscillations. The data reveal that |g| = 9.0, which is much enhanced with respect to the reported bulk value of 1.9. Surprisingly, in a large range of magnetic field and Landau level fillings, the value of the enhanced g-factor appears to be constant.Comment: 4 pages, 3 figure

Studying vessel biographies from the Heuneburg: an experimental approach

In the context of the BEFIM project (“Meanings and Functions of Mediterranean Imports in Early Iron Age Central Europe”) the life history of (drinking) vessels from the Early Celtic hillfort settlements of the Heuneburg was examined, studying the way of production and use. In order to do so, we set up an extensive experimental program of dozens of experiments directed at a better understanding of the way this pottery was made and used. The participation of an experienced potter allowed us to reproduce exact replicas of the supposed drinking ware and explore in detail the traces of production and the effect of temper, baking temperature and so forth on the development of production traces and wear. Especially variations in the temper material, like the frequently observed addition of calcite in the archaeological pottery, strongly affected the characteristics of the use-wear marks that developed from the preparation of different products (grape wine, honey wine, different kinds of porridge etc.). The influence of alcohol production, including fermentation, on the pottery was explored. We also tested the effect of different gestures of preparing food and drink (mixing, stirring, pounding), different ways of storage and handling, and the manner of consumption like decanting using various kinds of utensils. The traces we observed on the experimental vessels, using an integrated low and high power approach, formed the basis for our interpretation of the archaeological vessels from the Heuneburg

Patterns of impact resulting from a 'sit less, move more' web-based program in sedentary office employees.

PURPOSE: Encouraging office workers to 'sit less and move more' encompasses two public health priorities. However, there is little evidence on the effectiveness of workplace interventions for reducing sitting, even less about the longer term effects of such interventions and still less on dual-focused interventions. This study assessed the short and mid-term impacts of a workplace web-based intervention (Walk@WorkSpain, W@WS; 2010-11) on self-reported sitting time, step counts and physical risk factors (waist circumference, BMI, blood pressure) for chronic disease. METHODS: Employees at six Spanish university campuses (n=264; 42±10 years; 171 female) were randomly assigned by worksite and campus to an Intervention (used W@WS; n=129; 87 female) or a Comparison group (maintained normal behavior; n=135; 84 female). This phased, 19-week program aimed to decrease occupational sitting time through increased incidental movement and short walks. A linear mixed model assessed changes in outcome measures between the baseline, ramping (8 weeks), maintenance (11 weeks) and follow-up (two months) phases for Intervention versus Comparison groups. RESULTS: A significant 2 (group) × 2 (program phases) interaction was found for self-reported occupational sitting (F[3]=7.97, p=0.046), daily step counts (F[3]=15.68, p=0.0013) and waist circumference (F[3]=11.67, p=0.0086). The Intervention group decreased minutes of daily occupational sitting while also increasing step counts from baseline (446±126; 8,862±2,475) through ramping (+425±120; 9,345±2,435), maintenance (+422±123; 9,638±3,131) and follow-up (+414±129; 9,786±3,205). In the Comparison group, compared to baseline (404±106), sitting time remained unchanged through ramping and maintenance, but decreased at follow-up (-388±120), while step counts diminished across all phases. The Intervention group significantly reduced waist circumference by 2.1cms from baseline to follow-up while the Comparison group reduced waist circumference by 1.3cms over the same period. CONCLUSIONS: W@WS is a feasible and effective evidence-based intervention that can be successfully deployed with sedentary employees to elicit sustained changes on "sitting less and moving more"