25 research outputs found

    Exploring the role of work identity and work locus of control in information security awareness

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    A growing body of research evidence has been focused on exploring aspects of individual differences in the context of human factors and adherence to organisational information security. The present study aimed to extend this research by exploring three individual variables related directly to the individual's perceived control within the workplace, their commitment to current work identity, and the extent to which they are reconsidering commitment to work. A total 1003 participants aged between 18–65 (Mean = 40.29; SD = 12.28), who were in full or part-time employment took part in the study. The results demonstrated that work locus of control acted as a significant predictor for total scores on a measure of information security awareness. Those individuals who demonstrated more externality had weaker engagement in accepted information security within the workplace. The findings from the current study are discussed in the context of potential links to counterproductive work behaviours, as well as presenting possible practical routes for intervention strategies to help mitigate poor engagement in information security awareness

    Forced Convection Heat Transfer from a Finite-Height Cylinder

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    [EN] This paper presents a large eddy simulation of forced convection heat transfer in the flow around a surface-mounted finite-height circular cylinder. The study was carried out for a cylinder with height-to-diameter ratio of 2.5, a Reynolds number based on the cylinder diameter of 44 000 and a Prandtl number of 1. Only the surface of the cylinder is heated while the bottom wall and the inflow are kept at a lower fixed temperature. The approach flow boundary layer had a thickness of about 10% of the cylinder height. Local and averaged heat transfer coefficients are presented. The heat transfer coefficient is strongly affected by the free-end of the cylinder. As a result of the flow over the top being downwashed behind the cylinder, a vortex-shedding process does not occur in the upper part, leading to a lower value of the local heat transfer coefficient in that region. In the lower region, vortex-shedding takes place leading to higher values of the local heat transfer coefficient. The circumferentially averaged heat transfer coefficient is 20 % higher near the ground than near the top of the cylinder. The spreading and dilution of the mean temperature field in the wake of the cylinder are also discussed.The simulation was carried out using the supercomputing facilities of the Steinbuch Centre for Computing (SCC) of the Karlsruhe Institute of Technology. MGV has been partially supported by grant TRA2012-37714 of the Spanish Ministry of Economy and Competitiveness.García Villalba, M.; Palau-Salvador, G.; Rodi, W. (2014). Forced Convection Heat Transfer from a Finite-Height Cylinder. Flow, Turbulence and Combustion. 93(1):171-187. https://doi.org/10.1007/s10494-014-9543-7S171187931Ames, F., Dvorak, L.: Turbulent transport in pin fin arrays: experimental data and predictions. J. 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Fluids 21, 015101 (2009)Donnert, G.D., Kappler, M., Rodi, W.: Measurement of tracer concentration in the flow around finite-height cylinders. J. Turbul. 8, 33 (2007)Frederich, O., Thiele, F.: Turbulent flow dynamics caused by a truncated cylinder. Int. J. Heat Fluid Flow 32(3), 546–557 (2011)Fröhlich, J., García-Villalba, M., Rodi, W.: Scalar mixing and large–scale coherent structures in a turbulent swirling jet. Flow Turbul. Combust. 80, 47–59 (2008)Fröhlich, J., Rodi, W.: LES of the flow around a cylinder of finite height. Int. J. Heat Fluid Flow 25, 537–548 (2004)García-Villalba, M., Fröhlich, J.: LES of a free annular swirling jet–Dependence of coherent structures on a pilot jet and the level of swirl. Int. J. Heat Fluid Flow 27(5), 911–923 (2006)García-Villalba, M., Li, N., Rodi, W., Leschziner, M.A.: Large eddy simulation of separated flow over a three-dimensional axisymmetric hill. J. 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    Long-Term Effects of Environmental Lead Exposure on Blood Pressure and Plasma Soluble Cell Adhesion Molecules in Young Adults: A Follow-Up Study of a Prospective Cohort in Kosovo

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    Background and Aims. Epidemiologic studies examining the relationship between environmental lead (Pb) exposure and blood pressure (BP) generally report small associations between blood lead concentration (BPb) and BP. However, these studies are predominantly cross-sectional. In addition, no epidemiologic studies evaluate associations between either current or past Pb exposure and serum levels of markers of systemic inflammation and endothelial dysfunction, including soluble vascular adhesion molecule (sVCAM-1) and soluble intercellular cell adhesion molecule (sICAM-1). We prospectively investigate these associations later in life. Methods. From our original prospective birth cohort study in Mitrovica (a mining town) and Prishtina (a control town), Kosovo, from 1985 to 1998, we located and assessed BPb and BP in 101 participants (mean age of 24.9 years old) in 2011. Results. We found highly statistically significant association between concurrent BPb and sVCAM-1 in men and a marginally significant association between concurrent PBb and sICAM.-1 in women. We did not find evidence of mediation. Conclusion. Current study results, along with previously reported findings on this cohort, provide evidence for the hypothesis that exposure to Pb leads to small increases in sBP and perhaps to increased circulating levels of sVCAM-1 and sICAM-1 later in life

    Long-Term Effects of Environmental Lead on Erythropoietin Production in Young Adults: A Follow-Up Study of a Prospective Cohort in Kosovo

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    Background and Aims. Epidemiologic cross-sectional studies examining the relationship between environmental lead (Pb) exposure and erythropoietin (EPO) production have reported contrasting results. It is unknown, however, if exposure to Pb earlier in life has an effect on EPO production later in life. Here, using a prospective study, we evaluate the association between prenatal, early childhood, and concurrent Pb exposure and EPO concentration in young adulthood. Methods. From our prospective birth cohort study in Mitrovica (a mining town) and Pristina (a control town), Kosovo, from 1985 to 1998, we located and assessed blood lead concentration (BPb) and serum EPO in 101 participants (mean age 24.9 years) in 2011. We examined the association between BPb and EPO, stratified by hemoglobin (Hgb), and controlling for potential confounders. Results. These results resemble the findings in the original full cohort at 4.5 and 6.5 years of age, at which time we reported that the maintenance of a normal Hgb required increased EPO production among participants exposed to high levels of environmental Pb. In contrast, when the original cohort was 9.5 and 12 years of age, they were no longer capable of hyper-production of EPO in order to maintain normal levels of Hgb, suggestive of cumulative toxicity to the peritubular cells of the kidney that are responsible for EPO synthesis. Conclusion. Our results, along with previously reported findings on this cohort, suggest that a dramatic reduction of Pb exposure may allow for a reversal of the impact that prolonged Pb exposure may have on EPO production
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