469 research outputs found

    Петрографические признаки химически активных углей

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    Показані сліди газогенерації у вугіллі на природних сколах вугільних зразків. Описані їх особливості і походження. Запропоновано використовування їх для оцінки хімічної активності (газогенеруючої активності) гелифицированної речовини вугілля.Tracks of gasogeneration in a coal are shown on natural cleavage on coal samples. Described their features and origin. The use of them is offered for estimation of chemical activity (gasogeneration activity) of matter of gelification of coal

    Rock magnetic techniques complemented by ferromagnetic resonance spectroscopy to analyse a sediment record

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    Environmental magnetism uses the spatial and temporal occurrence of magnetic carriers as diagnostic tools to detect environmental changes. Concentration, composition, grain size and configuration of the carriers inferred from magnetic properties are key parameters, because they are indicative of the formation conditions of magnetic phases, and/or of processes such as diagenesis and weathering. We present a detailed ferromagnetic resonance (FMR) spectroscopy analysis in concert with routinely used rock magnetic measurements to determine these parameters in a sediment record that documents the development of Lake Soppensee (Central Switzerland) since latest Pleistocene. FMR spectroscopy monitors varying concentration of the predominant magnetite/maghemite by the spectral signal intensity, whereas the stable single domain and superparamagnetic states are determined by the signal shape at room and low temperature. Fitting and simulation of FMR spectra are successfully applied to samples with well-defined magnetite components in the sediment matrix. Clear evidence for the colonization of magnetotactic bacteria (MTB) in Lake Soppensee was possible by applying empirical spectral separation to measured FMR signals that yield two magnetite populations differing in their configuration, that is, dispersed and aligned in chains. Low temperature measurements showed that these MTB can be preserved as pure or oxidized magnetite. The FMR data set confirms and completes rock magnetic information obtained from the lacustrine sedimentary record. The advanced application of FMR spectroscopy in the presented study critically highlights the benefit of this rapid and non-destructive method for future analysis of magnetic properties in environmental studie

    Long-term air pollution exposure and living close to busy roads are associated with COPD in women

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    BACKGROUND: Lung function and exacerbations of chronic obstructive pulmonary disease (COPD) have been associated with short-term exposure to air pollution. However, the effect of long-term exposure to particulate matter from industry and traffic on COPD as defined by lung function has not been evaluated so far. Our study was designed to investigate the influence of long-term exposure to air pollution on respiratory symptoms and pulmonary function in 55-year-old women. We especially focused on COPD as defined by GOLD criteria and additionally compared the effects of air pollution on respiratory symptoms by questionnaire data and by lung function measurements. METHODS: In consecutive cross sectional studies conducted between 1985–1994, we investigated 4757 women living in the Rhine-Ruhr Basin of Germany. NO(2 )and PM(10 )exposure was assessed by measurements done in an 8 km grid, and traffic exposure by distance from the residential address to the nearest major road using Geographic Information System data. Lung function was determined and COPD was defined by using the GOLD criteria. Chronic respiratory symptoms and possible confounders were defined by questionnaire data. Linear and logistic regressions, including random effects were used to account for confounding and clustering on city level. RESULTS: The prevalence of COPD (GOLD stages 1–4) was 4.5%. COPD and pulmonary function were strongest affected by PM(10 )and traffic related exposure. A 7 μg/m(3 )increase in five year means of PM(10 )(interquartile range) was associated with a 5.1% (95% CI 2.5%–7.7%) decrease in FEV(1), a 3.7% (95% CI 1.8%–5.5%) decrease in FVC and an odds ratio (OR) of 1.33 (95% CI 1.03–1.72) for COPD. Women living less than 100 m from a busy road also had a significantly decreased lung function and COPD was 1.79 times more likely (95% CI 1.06–3.02) than for those living farther away. Chronic symptoms as based on questionnaire information showed effects in the same direction, but less pronounced. CONCLUSION: Chronic exposure to PM(10), NO(2 )and living near a major road might increase the risk of developing COPD and can have a detrimental effect on lung function

    Ultrafine particles, particle components and lung function at age 16 years:The PIAMA birth cohort study

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    Background: Particulate matter (PM) air pollution exposure has been linked to lung function in adolescents, but little is known about the relevance of specific PM components and ultrafine particles (UFP). Objectives: To investigate the associations of long-term exposure to PM elemental composition and UFP with lung function at age 16 years. Methods: For 706 participants of a prospective Dutch birth cohort, we assessed associations of forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) at age 16 with average exposure to eight elemental components (copper, iron, potassium, nickel, sulfur, silicon, vanadium and zinc) in PM2.5 and PM10, as well as UFP during the preceding years (age 13–16 years) estimated by land-use regression models. After assessing associations for each pollutant individually using linear regression models with adjustment for potential confounders, independence of associations with different pollutants was assessed in two-pollutant models with PM mass and NO2, for which associations with lung function have been reported previously. Results: We observed that for most PM elemental components higher exposure was associated with lower FEV1, especially PM10 sulfur [e.g. adjusted difference −2.23% (95% confidence interval (CI) −3.70 to −0.74%) per interquartile range (IQR) increase in PM10 sulfur]. The association with PM10 sulfur remained after adjusting for PM10 mass. Negative associations of exposure to UFP with both FEV1 and FVC were observed [-1.06% (95% CI: −2.08 to −0.03%) and −0.65% (95% CI: −1.53 to 0.23%), respectively per IQR increase in UFP], but did not persist in two-pollutant models with NO2 or PM2.5. Conclusions: Long-term exposure to sulfur in PM10 may result in lower FEV1 at age 16. There is no evidence for an independent effect of UFP exposure

    Air pollution and the development of asthma from birth until young adulthood

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    We used data of 3687 participants of the prospective Dutch PIAMA (Prevention and Incidence of Asthma and Mite Allergy) birth cohort and linked asthma incidence until age 20 years to estimated concentrations of nitrogen dioxide (NO2), particulate matter with a diameter <2.5 μm (PM2.5), <10 μm (PM10), and 2.5-10 μm, and PM2.5 absorbance ("soot") at the residential address. We assessed overall and age-specific associations with air pollution exposure with discrete time-hazard models, adjusting for potential confounders

    House dust endotoxin, asthma and allergic sensitization through childhood into adolescence

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    We used data of 854 participants of the prospective Dutch PIAMA birth cohort study with house dust endotoxin measurements at 3 months and/or 5-6 years and data on asthma and/or allergic sensitization from at least one of 11 follow-ups until age 17. We assessed overall and age-specific associations of the prevalence of asthma and sensitization with mattress and living room floor dust concentrations (per gram of dust) and loads (per m2 of sampling surface)

    A Phased Approach for preparation and organization of human biomonitoring studies.

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    Human biomonitoring (HBM) studies like other epidemiological studies are costly and time-consuming. They require the administration of questionnaires and collection of biological samples, putting substantial burden on the participants which may result in low participation rates. The growing importance of HBM studies in epidemiology, exposure assessment and risk assessment underline the importance of optimizing study planning, designing and implementation thus minimizing the above-mentioned difficulties. Based on frameworks from survey design and fieldwork preparation of the European Joint Program HBM4EU, the German Environment Surveys and the COPHES/DEMOCOPHES twin projects combined with elements of project management strategies, a Phased Approach has been developed, introducing a step-by-step guideline for the development of epidemiological studies. The Phased Approach splits the process of developing a study into six phases: Phase 0 (Scoping and Planning): All aspects that are necessary to conduct a study are compiled and put on the agenda for decision-making. Phase 1 (Preparation and Testing): Instruments (e.g. questionnaires), materials (e.g. guidelines, information), and ethics and data management issues, needing thorough preparation and testing before a study can start. Phase 2 (Initiation): Organization and acquisition of necessary equipment and engaging and training personnel. Phase 3 (Implementation): All procedures that require temporal proximity to the start date of fieldwork, such as obtaining contact information of invitees. Phase 4 (Fieldwork and Analysis): Involvement of participants and chemical analysis of the collected samples. Phase 5 (Results and Evaluation): Final procedures leading to closure of the project, such as providing and communicating results. The separation of the planning and conduct of human biomonitoring studies into different phases creates the basis for a structured procedure and facilitates a step-by-step approach reducing costs, warranting high participation rates and increasing quality of conduct. Emphasis is put on a comprehensive scoping phase ensuring high quality of the study design, which is indispensable for reliable results.This document has been created for the HBM4EU project. HBM4EU has received funding from the European Union's Horizon 2020 research and innovation program under grant agreement No 733032.S

    Early introduction of complementary foods and childhood overweight in breastfed and formula-fed infants in the Netherlands:the PIAMA birth cohort study

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    To investigate whether early introduction of complementary foods (CF) is associated with an increased risk of overweight during childhood, and whether this association differs between formula-fed and breastfed infants.We included 2611 participants that were born at term from a Dutch population-based birth cohort (n = 3963) designed to investigate the development of asthma and allergies. Parents kept records of their infant's age when CF were first introduced. Weight and height were parent reported yearly from age 1 to 8 years, and at ages 11, 14 and 17 years. We used multivariate generalized estimating equations analysis to investigate the association between timing of CF introduction (before 4 months vs at or after 4 months of age) and overweight at ages 1-17 years.Children with CF introduction before 4 months had higher odds of being overweight during childhood than children with CF introduction at or after 4 months (OR 1.32, 95% CI 1.19, 1.47). This association was observed in formula-fed infants (OR 1.51, 95% CI 1.17, 1.94) and breastfed infants (OR 1.32, 95% CI 1.19, 1.47). The duration of breastfeeding modified the association between CF introduction and overweight: children breastfed for shorter than 4 months, but not children breastfed for 4 months or longer with CF introduction before 4 months had higher odds of being overweight (OR 1.37, 95% CI 1.19, 1.57 and 1.07, 95% CI 0.87, 1.32, respectively), compared to those with CF introduction at or after 4 months.In children born at term, formula-fed infants and infants who were breastfed for shorter than 4 months, but not infants who were breastfed for 4 months or longer, had a higher risk of being overweight during childhood when being introduced to CF before 4 months of age.</p

    House Dust Mite Exposure through Human Milk and Dust: What Matters for Child Allergy Risk?

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    Allergies are major noncommunicable diseases associated with significant morbidity, reduced quality of life, and high healthcare costs. Despite decades of research, it is still unknown if early-life exposure to indoor allergens plays a role in the development of IgE-mediated allergy and asthma. The objective of this study is to contribute to the identification of early-life risk factors for developing allergy. We addressed whether two different sources of house dust mite Der p 1 allergen exposure during early life, i.e., human milk and dust, have different relationships with IgE levels and asthma outcomes in children. We performed longitudinal analyses in 249 mother–child pairs using data from the PIAMA birth cohort. Asthma symptoms and serum total and specific IgE levels in children were available for the first 16 years of life. Der p 1 levels were measured in human milk and dust samples from infant mattresses. We observed that infant exposure to Der p 1 through human milk was associated with an increased risk of having high levels of serum IgE (top tertile > 150 kU/mL) in childhood as compared to infants exposed to human milk with undetectable Der p 1 [adjusted OR (95% CI) 1.83 (1.05–3.20) p = 0.0294]. The Der p 1 content in infant mattress dust was not associated with increased IgE levels in childhood. The risk of asthma and Der p 1 sensitization was neither associated with Der p 1 in human milk nor with Der p 1 in dust. In conclusion, high levels of IgE in childhood were associated with Der p 1 exposure through human milk but not exposure from mattress dust. This observation suggests that human milk is a source of Der p 1 exposure that is relevant to allergy development and fosters the need for research on the determinants of Der p 1 levels in human milk
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