1,720,975 research outputs found
Does chronic exposure to high levels of nitrogen dioxide exacerbate the short-term effects of airborne particles?
No full textThe 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
No full textIntroduction 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
Causal inference methods in environmental epidemiology: different approaches to evaluate the health effects of industrial air pollution.
Full text linkThis study aims at implementing different causal inference approaches for the first time in a longitudinal cohort analysis with a continuous exposure, to assess the causal effect of industrial air pollution on health. A first review of the literature on the addressed causal inference methods is conducted, focusing on the main assumptions and suggested applications. Then the main longitudinal study, from which the causal inference methods originate, is described. A standard time-to-event analysis is performed to assess the relationship between exposure to air pollution (PM10 and SO2 from industrial origin) and mortality, as well as morbidity, in the cohort of residents around a large steel plant in the Taranto area (Apulia region, Italy). The Difference-in difference (DID) approach as well as three methods using the generalized propensity score (Propensity Function-PF of Imai and van Dyk, the Dose-response Function DRF by Hirano and Imbens, and the Robins’ Importance sampling-RIS using the GPS) were implemented in a Cox Proportional Hazard model for mortality. The main study demonstrated a negative effect of exposure to industrial air pollution on mortality and morbidity, after controlling for occupation, age, time period, and socioeconomic position index. The health effects were confirmed in all the causal approaches applied to the cohort, and the concentration-response curves showed increasing risk of natural and cause-specific mortality for higher levels of PM10 and SO2. We conclude that the health effects estimated are causal and that the adjustment for socioeconomic index already takes into account other, not measured, individual factors
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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