1,721,212 research outputs found

    Does chronic exposure to high levels of nitrogen dioxide exacerbate the short-term effects of airborne particles?

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    The short-term effects of PM10 on mortality and whether long-term exposure to NO2 modifies this association were investigated among 124,432 35+ year-old participants who died in Rome between 2001 and 2010 and maintained the same address for at least 5 years before death. Modification of PM10-related mortality by long-term NO2 exposure was determined by two-way interaction, while a three-way interaction was employed to assess effect modification of high NO2 levels in population groups defined by socio-demographic position and pre-existing diseases. An overall increase in mortality for each 10 Î1⁄4g/cu m increase in PM10 was observed. Short-term PM10-related mortality increased among people exposed to both high and low NO10 levels, but a clear effect modification was not detected. However, effect modifications of short-term PM10-related mortality were observed among those exposed to long-term NO2 for people over the age of 85-years, for those with pre-existing arrhythmias, and for those with pre-existing chronic obstructive pulmonary disease

    Saharan dust and the association between particulate matter and daily hospitalisations in Rome, Italy

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    Introduction Outbreaks of Saharan dust have been shown to exacerbate the effect of particulate matter (PM) on mortality. Their role on PM-morbidity association is less clear. This study aims to evaluate the effect of Saharan dust on the PM-hospitalisations association in Rome, Italy. Methods We studied residents hospitalised in Rome between 2001 and 2004 and performed a time-series analysis to explore the effects of PM2.5, PM2.5-10 and PM10 on cardiac, cerebrovascular and respiratory emergency hospitalisations, respectively. Saharan dust days were identified by combining Light Detection and Ranging observations and analyses from operational models. We tested a dust-PM interaction to evaluate the hypothesis that the PM effect on hospitalisations would be enhanced on dust days. Results We studied 77 354, 26 557 and 31 620 hospitalisations for cardiac, cerebrovascular and respiratory diseases, respectively, providing effect estimates per IQR. PM2.5-10 was associated with cardiac diseases (3.93%; 95% CI 1.58 to 6.34). PM 10 was associated with cardiac (3.37%; 95% CI 1.11 to 5.68), cerebrovascular (2.64%; 95% CI 0.06 to 5.29) and respiratory diseases (3.59%: 95% CI 0.18 to 7.12). No effect of PM2.5 was detected. Saharan dust modified the effect of the PM2.5-10 on respiratory hospitalisations, higher during dust days compared with dust-free days (14.63% vs -0.32%; p value of interaction=0.006). Saharan dust also increased the effect of PM10 on cerebrovascular diseases (5.04% vs 0.90%, p value of interaction=0.143). Discussion A clear enhanced effect of PM2.5-10 on respiratory diseases and of PM10 on cerebrovascular diseases emerged during Saharan dust outbreaks

    [A cohort study on mortality and morbidity in the area of Taranto, Southern Italy]

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    the area of Taranto has been investigated in several environmental and epidemiological studies due to the presence of many industrial plants and shipyards. Results from many studies showed excesses of mortality and cancer incidence for the entire city of Taranto, but there are no studies for different geographical areas of the city that take into account the important confounding effect of socioeconomic position

    A microscale hybrid modelling system to assess the air quality over a large portion of a large European city

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    The role of atmospheric dispersion models is becoming increasingly relevant to assess air pollution urban population exposure for epidemiological studies. Estimating urban air quality is challenging, because of the intrinsic characteristics of cities atmospheric structure, such as high density of primary emissions and presence of local dispersion processes, that produce strong concentration gradients. Therefore, very high spatial resolution simulations may often be required to improve the accuracy of estimations. The objective of this study is developing a microscale hybrid modelling system (HMS) to carry out, in a reasonable computational time, long-term simulations providing hourly concentration fields at building-resolving scale in extended urban areas in order to calculate annual indicators to evaluate exposure. The proposed system couples two atmospheric dispersion models suited for different scales: a Eulerian chemical transport model, FARM (Flexible Air quality Regional Model), accounting for dispersion phenomena due to regional and local emission sources, and a Lagrangian particle micro-scale dispersion model, PMSS (Parallel Micro Swift Spray), used to compute concentrations induced by vehicular traffic inside the city. The HMS has been applied on 12 × 12 km2 domain in Rome with a horizontal resolution of 4 m for calculating NO2 and PM10 concentrations for all year 2015. This study has been carried out in the frame of project BEEP (Big data in Environmental and occupational Epidemiology), that is an Italian research project in epidemiological field. Results show that the combined use of the two models reproduces the spatial and temporal variability of the observed atmospheric pollutants with a good agreement. The statistical analysis performed on daily average concentrations proves that the HMS suits the standard acceptance criteria for urban dispersion model evaluation, with a FAC2 of 0.92 and 0.80 and a Fractional Bias of −0.03 and −0.2 for NO2 and PM10 respectively. Furthermore, the implementation of an innovative kernel method to calculate concentrations in PMSS has made possible to reduce the computational time by 80%, leading to an average computational time of 3 h per simulated day on an HPC (High Performance Computing) system with 180 cores

    Long-term exposure to air pollution and risk of venous thromboembolism in a large administrative cohort

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    Background: Venous thromboembolisms (VTE) are one of the most frequent cause among the cardiovascular diseases. Despite the association between long-term exposure to air pollution and cardiovascular outcomes have been widely explored in epidemiological literature, little is known about the air pollution related effects on VTE. We aimed to evaluate this association in a large administrative cohort in 15 years of follow-up. Methods: Air pollution exposure (NO2, PM10 and PM2.5) was derived by land use regression models obtained by the ESCAPE framework. Administrative health databases were used to identify VTE cases. To estimate the association between air pollutant exposures and risk of hospitalizations for VTE (in total and divided in deep vein thrombosis (DVT) and pulmonary embolism (PE)), we used Cox regression models, considering individual, environmental (noise and green areas), and contextual characteristics. Finally, we considered potential effect modification for individual covariates and previous comorbidities. Results: We identified 1,954 prevalent cases at baseline and 20,304 cases during the follow-up period. We found positive associations between PM2.5 exposures and DVT, PE and VTE with hazard ratios (HRs) up to 1.082 (95% confidence intervals: 0.992, 1.181), 1.136 (0.994, 1.298) and 1.074 (0.996, 1.158) respectively for 10 μg/m3 increases. The association was stronger in younger subjects (< 70 years old compared to > 70 years old) and among those who had cancer. Conclusion: The effect of pollutants on PE and VTE hospitalizations, although marginally non-significant, should be interpreted as suggestive of a health effect that deserves attention in future studies

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed

    Variations on the Author

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    “Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship

    Appropriate Similarity Measures for Author Cocitation Analysis

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    We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis

    Modeling regulating ecosystem services along the urban–rural gradient: A comprehensive analysis in seven Italian coastal cities

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    Over the last decades, the environmental burden borne by natural ecosystems to sustain life in urban areas has considerably increased. For this reason, the network of interconnected green areas and features, referred to as Urban Green Infrastructure, is increasingly being promoted as a valuable means to enhance the life quality of city dwellers by providing Ecosystem Services.We present a spatial analysis of Ecosystem Services provision and synergies/trade-offs along the urban–rural gradient for the following Italian coastal Metropolitan cities: Genoa, Rome, Bari, Naples, Cagliari, Reggio Calabria and Palermo. We focused our attention on three macro classes of human-induced environmental pressures that are particularly critical to the quality of life in urban contexts, namely air pollution, Urban Heat Island effect, and alteration of the water cycle.We found that all of the selected Ecosystem Services, besides a few exceptions, are provided as a bundle, which means they appear together repeatedly, forming an association. On average, the Ecosystem Services provision grows at comparable paces moving from the inner urban core towards the peri-urban and rural areas. As a consequence, most densely urbanized areas were found to be Ecosystem Services coldspots compared to peri-urban and rural areas
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