777 research outputs found

    Kraken in Amsterdam anno 2009

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    Contribution to a ranking procedure for polymeric caotings and hydrophobic agents for concrete

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    One of the possible ways to protect the concrete is using coatings and hydrophobic agents that act as a barrier against the environment. When selecting the material for concrete protection, importance should be given to these properties of diffusion and permeability. The coatings and the hydrophobic agents must stop the penetration of water and delay the influence of aggressive agents, allowing the structure to breathe by a water vapour diffusion mechanism. An evaluation of the surface layer transport properties gives information on the durability of a particular concrete. In order to make the selection of coatings and hydrophobic agents for concrete protection, it is important to analyse the compound’s technical and economical performances. A ranking procedure, developed by Czarnecki and Lukowski, is applied on a series of concrete protection products. The ranking procedure is applied to evaluate durability experiments, carried out on some commercially available silicone, acrylic and epoxy compounds for surface treatment of concrete. The ranking procedure transforms experimental data of properties into one numerical value, by which the products can be classified according to the way on which their properties present an optimised or even best buy combination. The paper shows the use of the ranking procedure methodology, and points at the importance of the choice of the criteria and of their relative weight factor in the evaluation. The method is a valuable tool for the ranking of similar materials, whose performance is based on the same or similar physical or chemical processes

    Socio-economic factors, gender and smoking as determinants of COPD in a low-income country of sub-Saharan Africa: FRESH AIR Uganda.

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    In Uganda, biomass smoke seems to be the largest risk factor for the development of COPD, but socio-economic factors and gender may have a role. Therefore, more in-depth research is needed to understand the risk factors. The aim of this study was to investigate the impact of socio-economic factors and gender differences on the COPD prevalence in Uganda. The population comprised 588 randomly selected participants (>30 years) who previously completed the FRESH AIR Uganda study. In this post hoc analysis, the impact of several socio-economic characteristics, gender and smoking on the prevalence of COPD was assessed using a logistic regression model. The main risk factors associated with COPD were non-Bantu ethnicity (odds ratio (OR) 1.73, 95% confidence interval (CI) 1.06-2.82, P=0.030), biomass fuel use for heating (OR 1.76, 95% CI 1.03-3.00, P=0.038), former smoker (OR 1.87, 95% CI 0.97-3.60, P=0.063) and being unmarried (OR 0.087, 95% CI 0.93-2.95, P=0.087). A substantial difference in the prevalence of COPD was seen between the two ethnic groups: non-Bantu 20% and Bantu 12.9%. Additional analysis between these two groups showed significant differences in socio-economic circumstances: non-Bantu people smoked more (57.7% vs 10.7%), lived in tobacco-growing areas (72% vs 14.8%) and were less educated (28.5% vs 12.9% had no education). With regard to gender, men with COPD were unmarried (OR 3.09, 95% CI 1.25-7.61, P=0.015) and used more biomass fuel for heating (OR 2.15, 95% CI 1.02-4.54, P=0.045), and women with COPD were former smokers (OR 3.35, 95% CI 1.22-9.22, P=0.019). Only a few socio-economic factors (i.e., smoking, biomass fuel use for heating, marital status and non-Bantu ethnicity) have been found to be associated with COPD. This applied for gender differences as well (i.e., for men, marital status and biomass fuel for heating, and for women being a former smoker). More research is needed to clarify the complexity of the different risk factors

    Occupational exposure to gases/fumes and mineral dust affect DNA methylation levels of genes regulating expression

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    Many workers are daily exposed to occupational agents like gases/fumes, mineral dust or biological dust, which could induce adverse health effects. Epigenetic mechanisms, such as DNA methylation, have been suggested to play a role. We therefore aimed to identify differentially methylated regions (DMRs) upon occupational exposures in never-smokers and investigated if these DMRs associated with gene expression levels. To determine the effects of occupational exposures independent of smoking, 903 never-smokers of the LifeLines cohort study were included. We performed three genome-wide methylation analyses (Illumina 450 K), one per occupational exposure being gases/fumes, mineral dust and biological dust, using robust linear regression adjusted for appropriate confounders. DMRs were identified using comb-p in Python. Results were validated in the Rotterdam Study (233 never-smokers) and methylation-expression associations were assessed using Biobank-based Integrative Omics Study data (n = 2802). Of the total 21 significant DMRs, 14 DMRs were associated with gases/fumes and 7 with mineral dust. Three of these DMRs were associated with both exposures (RPLP1 and LINC02169 (2x)) and 11 DMRs were located within transcript start sites of gene expression regulating genes. We replicated two DMRs with gases/fumes (VTRNA2-1 and GNAS) and one with mineral dust (CCDC144NL). In addition, nine gases/fumes DMRs and six mineral dust DMRs significantly associated with gene expression levels. Our data suggest that occupational exposures may induce differential methylation of gene expression regulating genes and thereby may induce adverse health effects. Given the millions of workers that are exposed daily to occupational exposures, further studies on this epigenetic mechanism and health outcomes are warranted

    Association between Household Air Pollution Exposure and Chronic Obstructive Pulmonary Disease Outcomes in 13 Low- and Middle-Income Country Settings.

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    RATIONALE: Forty percent of households worldwide burn biomass fuels for energy, which may be the most important contributor to household air pollution. OBJECTIVES: To examine the association between household air pollution exposure and chronic obstructive pulmonary disease (COPD) outcomes in 13 resource-poor settings. METHODS: We analyzed data from 12,396 adult participants living in 13 resource-poor, population-based settings. Household air pollution exposure was defined as using biomass materials as the primary fuel source in the home. We used multivariable regressions to assess the relationship between household air pollution exposure and COPD outcomes, evaluated for interactions, and conducted sensitivity analyses to test the robustness of our findings. MEASUREMENTS AND MAIN RESULTS: Average age was 54.9 years (44.2-59.6 yr across settings), 48.5% were women (38.3-54.5%), prevalence of household air pollution exposure was 38% (0.5-99.6%), and 8.8% (1.7-15.5%) had COPD. Participants with household air pollution exposure were 41% more likely to have COPD (adjusted odds ratio, 1.41; 95% confidence interval, 1.18-1.68) than those without the exposure, and 13.5% (6.4-20.6%) of COPD prevalence may be caused by household air pollution exposure, compared with 12.4% caused by cigarette smoking. The association between household air pollution exposure and COPD was stronger in women (1.70; 1.24-2.32) than in men (1.21; 0.92-1.58). CONCLUSIONS: Household air pollution exposure was associated with a higher prevalence of COPD, particularly among women, and it is likely a leading population-attributable risk factor for COPD in resource-poor settings

    A hero doesn’t fall - moral dilemmas when a celebrated insider goes astray

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    Bill Cosby, Jimmy Savile and Gerrit Achterberg lived in different periods, in the US, UK, and the Netherlands. They were heroes because of what they accomplished during their professional careers but all three turned out to have committed serious crimes. Disclosure is painful, not only for the hero who comes to fall but also for the community that finds itself redefining moral standards when losing a celebrated insider. For this reason, the crimes of these three men have been concealed and kept secret for years. In comparing the three cases, this article tries to find out who decides on keeping the hero on his feet, how this is done, and if this changes over time
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