The Australian Work Exposures Study: Prevalence of Occupational Exposure to Respirable Crystalline Silica

Background: Respirable crystalline silica (RCS) is a biologically active dust that can accumulate in the lung and induce silicosis and lung cancer. Despite occupational exposure being the predominant source, no study has described current occupational RCS exposure on a national scale in Australia. The aim of this study is to estimate the characteristics of those exposed and the circumstances of RCS exposure in Australian workplaces. Methods: A cross-sectional survey of the Australian working population (18–65 years old) was conducted. Information about the respondents’ current job and their demographic characteristics was collected in a telephone interview. Occupational exposure to RCS was determined based on preprogrammed decision rules regarding potential levels of exposure associated with self-reported tasks. Results: Overall, 6.4% of respondents were deemed exposed to RCS at work in 2012 (3.3% were exposed at a high level). The exposure varied with sex, state of residence, and socioeconomic status. Miners and construction workers were most likely to be highly exposed to RCS when performing tasks with concrete or cement or working near crushers that create RCS-containing dusts. When extrapolated to the entire Australian working population, 6.6% of Australian workers were exposed to RCS and 3.7% were highly exposed when carrying out tasks at work. Conclusion: This is the first study investigating occupational RCS exposure in an entire national working population. The information about occupational tasks that lead to high level RCS exposure provided by this study will inform the direction of occupational interventions and policies

Left-handedness and risk of breast cancer

Left-handedness may be an indicator of intrauterine exposure to oestrogens, which may increase the risk of breast cancer. Women (n=1786) from a 1981 health survey in Busselton were followed up using death and cancer registries. Left-handers had higher risk of breast cancer than right-handers and the effect was greater for post-menopausal breast cancer (hazard ratio=2.59, 95% confidence interval 1.11–6.03)

Chronotype and environmental light exposure in a student population

In humans and most other species, changes in the intensity and duration of light provide a critical set of signals for the synchronisation of the circadian system to the astronomical day. The timing of activity within the 24 h day defines an individual’s chronotype, i.e. morning, intermediate or evening type. The aim of this study was to investigate the associations between environmental light exposure, due to geographical location, on the chronotype of university students. Over 6 000 university students from cities in the Northern Hemisphere (Oxford, Munich and Groningen) and Southern Hemisphere (Perth, Melbourne and Auckland) completed the Munich ChronoType Questionnaire. In parallel, light measures (daily irradiance, timing of sunrise and sunset) were compiled from satellite or ground stations at each of these locations. Our data shows that later mid-sleep point on free days (corrected for oversleep on weekends MFSsc) is associated with (i) residing further from the equator, (ii) a later sunset, (iii) spending more time outside and (iv) waking from sleep significantly after sunrise. However, surprisingly, MSFscdid not correlate with daily light intensity at the different geographical locations. Although these findings appear to contradict earlier studies suggesting that in the wider population increased light exposure is associated with an earlier chronotype, our findings are derived exclusively from a student population aged between 17 and 26 years. We therefore suggest that the age and occupation of our population increase the likelihood that these individuals will experience relatively little light exposure in the morning whilst encountering more light exposure later in the day, when light has a delaying effect upon the circadian system

Design of urban furniture to enhance the soundscape: A case study

In modern urban scenarios all the aspects of the historical heritage, including public open spaces and ancient buildings, have to meet the high increase of density of infrastructures and constructions, with the consequent change of visual and sound environments. This in turn affects people’s quality of life. Because of the growing interest on this problem, this study investigates the relationship between soundscape and design solutions for urban furniture, considering technical and environmental feasibility of the designing process, from the materials characteristics, to the acoustic and psychoacoustic impact of the tool on the user. The process includes the acoustic suitability of 3D printing materials, the suitability of acoustic design using software simulation, the experimental assessment of the performance of the 3D printed prototype, and the statistical evaluation of the chosen studying parameters and conditions. This paper describes all the stages of the designing process, with a focus on the study of shapes and volumes of the prototype and on its impact on the user’s perception. FEM simulations and experimental tests performed in a semi-anechoic chamber allowed to validate the design process. These analyses proved that the designed prototype of urban furniture can not only positively influence the physical environment but also the psychoacoustic perception of it

Tritium Beta Decay, Neutrino Mass Matrices and Interactions Beyond the Standard Model

The interference of charge-changing interactions, weaker than the V-A Standard Model (SM) interaction and having a different Lorentz structure, with that SM interaction, can, in principle, produce effects near the end point of the Tritium beta decay spectrum which are of a different character from those produced by the purely kinematic effect of neutrino mass expected in the simplest extension of the SM. We show that the existence of more than one mass eigenstate can lead to interference effects at the end point that are stronger than those occurring over the entire spectrum. We discuss these effects both for the special case of Dirac neutrinos and the more general case of Majorana neutrinos and show that, for the present precision of the experiments, one formula should suffice to express the interference effects in all cases. Implications for "sterile" neutrinos are noted.Comment: 32 pages, LaTeX, 6 figures, PostScript; full discussion and changes in notation from Phys. Lett. B440 (1998) 89, nucl-th/9807057; submitted to Phys. Rev.

Beliefs and perceptions about the causes of breast cancer: a case-control study

Background: Attributions of causality are common for many diseases, including breast cancer. The risk of developing breast cancer can be reduced by modifications to lifestyle and behaviours to minimise exposure to specific risk factors, such as obesity. However, these modifications will only occur if women believe that certain behaviours/lifestyle factors have an impact on the development of breast cancer. Method: The Breast Cancer, Environment and Employment Study is a case-control study of breast cancer conducted in Western Australia between 2009 and 2011. As part of the study 1109 women with breast cancer and 1633 women without the disease completed a Risk Perception questionnaire in which they were asked in an open-ended question for specific cause/s to the development of breast cancer in themselves or in others. The study identified specific causal beliefs, and assessed differences in the beliefs between women with and without breast cancer. Results: The most common attributions in women without breast cancer were to familial or inherited factors (77.6%), followed by lifestyle factors, such as poor diet and smoking (47.1%), and environmental factors, such as food additives (45.4%). The most common attributions in women with breast cancer were to mental or emotional factors (46.3%), especially stress, followed by lifestyle factors (38.6%) and physiological factors (37.5%), particularly relating to hormonal history.Conclusions: While the majority of participants in this study provided one or more causal attributions for breast cancer, many of the reported risk factors do not correspond to those generally accepted by the scientific community. These misperceptions could be having a significant impact on the success of prevention and early detection programs that seek to minimise the pain and suffering caused by this disease. In particular, women who have no family history of the disease may not work to minimise their exposure to the modifiable risk factors

The genetic basis for panicle trait variation in switchgrass (Panicum virgatum)

Key message: We investigate the genetic basis of panicle architecture in switchgrass in two mapping populations across a latitudinal gradient, and find many stable, repeatable genetic effects and limited genetic interactions with the environment. Abstract: Grass species exhibit large diversity in panicle architecture influenced by genes, the environment, and their interaction. The genetic study of panicle architecture in perennial grasses is limited. In this study, we evaluate the genetic basis of panicle architecture including panicle length, primary branching number, and secondary branching number in an outcrossed switchgrass QTL population grown across ten field sites in the central USA through multi-environment mixed QTL analysis. We also evaluate genetic effects in a diversity panel of switchgrass grown at three of the ten field sites using genome-wide association (GWAS) and multivariate adaptive shrinkage. Furthermore, we search for candidate genes underlying panicle traits in both of these independent mapping populations. Overall, 18 QTL were detected in the QTL mapping population for the three panicle traits, and 146 unlinked genomic regions in the diversity panel affected one or more panicle trait. Twelve of the QTL exhibited consistent effects (i.e., no QTL by environment interactions or no QTL × E), and most (four of six) of the effects with QTL × E exhibited site-specific effects. Most (59.3%) significant partially linked diversity panel SNPs had significant effects in all panicle traits and all field sites and showed pervasive pleiotropy and limited environment interactions. Panicle QTL co-localized with significant SNPs found using GWAS, providing additional power to distinguish between true and false associations in the diversity panel

Lifetime physical activity and risk of breast cancer in pre-and post-menopausal women

© 2015 Springer Science+Business Media New York To investigate the association between different types of physical activity (PA) and breast cancer. A case–control study of breast cancer was conducted in Western Australia from 2009 to 2011, in which 1205 women with breast cancer and 1789 frequency age-matched breast cancer-free control women were recruited. A self-administered questionnaire was used to collect information about lifetime and age-period recreational, household, occupational and transport physical activities. Detailed questions about demographic characteristics, and relevant reproductive, medical and lifestyle factors were also included. Logistic regression and restrictive cubic spline analyses were applied to investigate the association and dose–response relationship between PA and breast cancer risk. Subgroup analysis was performed regarding menopausal status. We found non-linear dose–response associations between PA and risk of breast cancer. Overall, 95–130 MET-hours/week of total lifetime PA was associated with the lowest breast cancer risk. The effects were stronger among post-menopausal women. We also found that the medium amounts of recreational PA (up to 21 MET-hours/week) were associated with lower breast cancer risk among post-menopausal women. Further analysis on the intensity of recreational PA demonstrated different dose–response associations between moderate- and vigorous-intensity recreational PA and breast cancer risk. We found that PA was associated with a reduced risk of breast cancer among post-menopausal women, but not in a linear fashion. Recreational PA of different intensities may have different dose–response associations with risk of breast cancer