9,045 research outputs found

    A Community Education and Intervention Program for Level Crossing Risk Management in Australia

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    This project aims to design, implement and evaluate a community road safety program using an intervention and control community methodology. It is a 3-year national project funded by the Cooperative Research Centre for Railway Engineering and Technologies in Australia. With level crossing accidents constituting a significant proportion of death and injury associated with rail operations the need to conduct research in level crossing safety is warranted. To date, there has been little research conducted in Australia that evaluates community road safety programs targeting level crossing safety as well as identifying impediments towards the development of safe level crossing behaviour

    Adverse socioeconomic conditions in childhood and cause specific adult mortality: prospective observational study

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    <b>Objective:</b> To investigate the association between social circumstances in childhood and mortality from various causes of death in adulthood. Design: Prospective observational study. Setting: 27 workplaces in the west of Scotland. <b>Subjects:</b> 5645 men aged 35-64 years at the time of examination. <b>Main outcome measures:</b> Death from various causes. <b>Results:</b> Men whose fathers had manual occupations when they were children were more likely as adults to have manual jobs and be living in deprived areas. Gradients in mortality from coronary heart disease, stroke, lung cancer, stomach cancer, and respiratory disease were seen (all P<0.05), generally increasing from men whose fathers had professional and managerial occupations (social class I and II) to those whose fathers had semiskilled and unskilled manual occupations (social class IV and V). Relative rates of mortality adjusted for age for men with fathers in manual versus non-manual occupations were 1.52 (95% confidence interval 1.24 to 1.87) for coronary heart disease, 1.83 (1.13 to 2.94) for stroke, 1.65 (1.12 to 2.43) for lung cancer, 2.06 (0.93 to 4.57) for stomach cancer, and 2.01 (1.17 to 3.48) for respiratory disease. Mortality from other cancers and accidental and violent death showed no association with fathers' social class. Adjustment for adult socioeconomic circumstances and risk factors did not alter results for mortality from stroke and stomach cancer, attenuated the increased risk of coronary heart disease and respiratory disease, and essentially eliminated the association with lung cancer. <b>Conclusions:</b> Adverse socioeconomic circumstances in childhood have a specific influence on mortality from stroke and stomach cancer in adulthood, which is not due to the continuity of social disadvantage throughout life. Deprivation in childhood influences risk of mortality from coronary heart disease and respiratory disease in adulthood, although an additive influence of adulthood circumstances is seen in these cases. Mortality from lung cancer, other cancer, and accidents and violence is predominantly influenced by risk factors that are related to social circumstances in adulthood

    Some social and physical correlates of intergenerational social mobility: evidence from the west of Scotland Collaborative Study

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    Mainstream sociological studies of intergenerational social mobility have emphasised social factors such as education and the material and cultural resources of the family of origin as the main influences on the chances and direction of social mobility. Medical sociology in contrast has been more interested in its physical correlates such as height and health status. Data from the West of Scotland Collaborative study allow an examination of the relationship between social mobility and both social and physical factors. Height, education and material circumstances in the family of origin, indexed as the number of siblings, were each independently associated with the chances of both upward and downward social mobility in this dataset. In each case the net effect of this social mobility was to constrain the social distribution of these variables. Any role which these factors may play in indirect health selection, it is argued, cannot account for social class differences in adult health

    Carboxyhaemoglobin concentration, smoking habit, and mortality in 25 years in the Renfrew/Paisley prospective cohort study

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    Objective: To investigate how carboxyhaemoglobin concentration is related to smoking habit and to assess whether carboxyhaemoglobin concentration is related to mortality. Design: Prospective cohort study. Setting: Residents of the towns of Renfrew and Paisley in Scotland. Participants: The whole Renfrew/Paisley study, conducted between 1972 and 1976, consisted of 7048 men and 8354 women aged 45–64 years. This study was based on 3372 men and 4192 women who were screened after the measurement of carboxyhaemoglobin concentration was introduced about halfway through the study. Main outcome measures: Deaths from coronary heart disease (CHD), stroke, chronic obstructive pulmonary disease (COPD), lung cancer, and all causes in 25 years after screening. Results: Carboxyhaemoglobin concentration was related to self reported smoking and for each smoking category was higher in participants who reported inhaling than in those who reported not inhaling. Carboxyhaemoglobin concentration was positively related to all causes of mortality analysed (relative rates associated with a 1 SD (2.93) increase in carboxyhaemoglobin for all causes, CHD, stroke, COPD, and lung cancer were 1.26 (95% confidence interval (CI) 1.19 to 1.34), 1.19 (95% CI 1.13 to 1.26), 1.19 (95% CI 1.13 to 1.26), 1.64 (95% CI 1.47 to 1.84), and 1.69 (95% CI 1.60 to 1.79), respectively). Adjustment for self reported cigarette smoking attenuated the associations but they remained relatively strong. Conclusions: Self reported smoking data were validated by the objective measure of carboxyhaemoglobin concentration. Since carboxyhaemoglobin concentration remained associated with mortality after adjustment for smoking, carboxyhaemoglobin seems to capture more of the risk associated with smoking tobacco than does self reported tobacco consumption alone. Analysing mortality by self reported cigarette smoking underestimates the strength of association between smoking and mortality

    Further thoughts on precision

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    Background: There has been much discussion amongst automated software defect prediction researchers regarding use of the precision and false positive rate classifier performance metrics. Aim: To demonstrate and explain why failing to report precision when using data with highly imbalanced class distributions may provide an overly optimistic view of classifier performance. Method: Well documented examples of how dependent class distribution affects the suitability of performance measures. Conclusions: When using data where the minority class represents less than around 5 to 10 percent of data points in total, failing to report precision may be a critical mistake. Furthermore, deriving the precision values omitted from studies can reveal valuable insight into true classifier performancePeer reviewedFinal Accepted Versio

    Infrared spectrum and stability of a π-type hydrogen-bonded complex between the OH and C2H2 reactants

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    A hydrogen-bonded complex between the hydroxyl radical and acetylene has been stabilized in the reactant channel well leading to the addition reaction and characterized by infrared action spectroscopy in the OH overtone region. Analysis of the rotational band structure associated with the a-type transition observed at 6885.53(1) cm−1 (origin) reveals a T-shaped structure with a 3.327(5) Å separation between the centers of mass of the monomer constituents. The OH (v = 1) product states populated following vibrational predissociation show that dissociation proceeds by two mechanisms: intramolecular vibrational to rotational energy transfer and intermolecular vibrational energy transfer. The highest observed OH product state establishes an upper limit of 956 cm−1 for the stability of the π-type hydrogen-bonded complex. The experimental results are in good accord with the intermolecular distance and well depth at the T-shaped minimum energy configuration obtained from complementary ab initio calculations, which were carried out at the restricted coupled cluster singles, doubles, noniterative triples level of theory with extrapolation to the complete basis set limit

    Evidence for partial quenching of orbital angular momentum upon complex formation in the infrared spectrum of OH-acetylene

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    The entrance channel leading to the addition reaction between the hydroxyl radical and acetylene has been examined by spectroscopic characterization of the asymmetric CH stretching band of the π-hydrogen bonded OH-acetylene reactant complex. The infrared action spectrum observed at 3278.6 cm−1 (origin) consists of seven peaks of various intensities and widths, and is very different from those previously reported for closed-shell HF/HCl-acetylene complexes. The unusual spectrum arises from a partial quenching of the OH orbital angular momentum in the complex, which in turn is caused by a significant splitting of the OH monomer orbital degeneracy into 2A′ and 2A″ electronic states. The magnitude of the 2A′−2A″ splitting as well as the A rotational constant for the OH-acetylene complex are determined from the analysis of this b-type infrared band. The most populated OH product rotational state, jOH = 9/2, is consistent with intramolecular vibrational energy transfer to the ν2 C≡C stretching mode of the departing acetylene fragment. The lifting of the OH orbital degeneracy and partial quenching of its electronic orbital angular momentum indicate that the electronic changes accompanying the evolution of reactants into products have begun to occur in the reactant complex

    Psychological stress and cardiovascular disease: empirical demonstration of bias in a prospective observational study of Scottish men

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    Objectives: To examine the association between self perceived psychological stress and cardiovascular disease in a population where stress was not associated with social disadvantage. Design: Prospective observational study with follow up of 21 years and repeat screening of half the cohort 5 years from baseline. Measures included perceived psychological stress, coronary risk factors, self reported angina, and ischaemia detected by electrocardiography. Setting: 27 workplaces in Scotland. Participants: 5606 men (mean age 48 years) at first screening and 2623 men at second screening with complete data on all measures Main outcome measures: Prevalence of angina and ischaemia at baseline, odds ratio for incident angina and ischaemia at second screening, rate ratios for cause specific hospital admission, and hazard ratios for cause specific mortality. Results: Both prevalence and incidence of angina increased with increasing perceived stress (fully adjusted odds ratio for incident angina, high versus low stress 2.66, 95% confidence interval 1.61 to 4.41; P for trend <0.001). Prevalence and incidence of ischaemia showed weak trends in the opposite direction. High stress was associated with a higher rate of admissions to hospital generally and for admissions related to cardiovascular disease and psychiatric disorders (fully adjusted rate ratios for any general hospital admission 1.13, 1.01 to 1.27, cardiovascular disease 1.20, 1.00 to 1.45, and psychiatric disorders 2.34, 1.41 to 3.91). High stress was not associated with increased admission for coronary heart disease (1.00, 0.76-1.32) and showed an inverse relation with all cause mortality, mortality from cardiovascular disease, and mortality from coronary heart disease, that was attenuated by adjustment for occupational class (fully adjusted hazard ratio for all cause mortality 0.94, 0.81 to 1.11, cardiovascular mortality 0.91, 0.78 to 1.06, and mortality from coronary heart disease 0.98, 0.75 to 1.27). Conclusions: The relation between higher stress, angina, and some categories of hospital admissions probably resulted from the tendency of participants reporting higher stress to also report more symptoms. The lack of a corresponding relation with objective indices of heart disease suggests that these symptoms did not reflect physical disease. The data suggest that associations between psychosocial measures and disease outcomes reported from some other studies may be spurious

    Associations of height, leg length, and lung function with cardiovascular risk factors in the Midspan Family Study

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    <b>Background</b>: Taller people and those with better lung function are at reduced risk of coronary heart disease (CHD). Biological mechanisms for these associations are not well understood, but both measures may be markers for early life exposures. Some studies have shown that leg length, an indicator of pre-pubertal nutritional status, is the component of height most strongly associated with CHD risk. Other studies show that height-CHD associations are greatly attenuated when lung function is controlled for. This study examines (1) the association of height and the components of height (leg length and trunk length) with CHD risk factors and (2) the relative strength of the association of height and forced expiratory volume in one second (FEV1) with risk factors for CHD. <b>Subjects and methods</b>: Cross sectional analysis of data collected at detailed cardiovascular screening examinations of 1040 men and 1298 women aged 30–59 whose parents were screened in 1972–76. Subjects come from 1477 families and are members of the Midspan Family Study. <b>Setting</b>: The towns of Renfrew and Paisley in the West of Scotland. <b>Results</b>: Taller subjects and those with better lung function had more favourable cardiovascular risk factor profiles, associations were strongest in relation to FEV1. Higher FEV1 was associated with lower blood pressure, cholesterol, glucose, fibrinogen, white blood cell count, and body mass index. Similar, but generally weaker, associations were seen with height. These associations were not attenuated in models controlling for parental height. Longer leg length, but not trunk length, was associated with lower systolic and diastolic blood pressure. Longer leg length was also associated with more favourable levels of cholesterol and body mass index than trunk length. <b>Conclusions</b>:These findings provide indirect evidence that measures of lung development and pre-pubertal growth act as biomarkers for childhood exposures that may modify an individual's risk of developing CHD. Genetic influences do not seem to underlie height-CHD associations
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