1,720,982 research outputs found
Pension reforms, longer working horizons and depression. Does the risk of automation matter?
We investigate the effect of postponing minimum retirement age on middle-aged workers' depression. Using pension reforms in several European countries and data from the SHARE survey, we find that depression increases with a longer work horizon, but only among workers in occupations with a relatively high risk of automation. We explain our results with the higher job insecurity associated with occupations that are more exposed to automation, and rule out alternatives, including pension wealth effects and the differential exposure of occupations to the business cycle
Decreases in serum PFAS are associated with decreases in serum lipids: A longitudinal study on a highly exposed population
Introduction: Perfluoroalkyl substances (PFAS) are widely used, ubiquitous and highly persistent man-made chemicals. Previous cross-sectional studies have consistently linked PFAS exposure to alterations in lipid profiles. However, longitudinal investigations are preferred to mitigate issues related to reverse causation and confounding. Hence, we aimed to investigate the association between changes in serum PFAS and changes in serum lipids, while shedding light on potential modifiers of the examined relationships. Methods: We used data from a health surveillance program offered to residents of a vast area of the Veneto Region (North-Eastern Italy), who had been exposed to PFAS via contaminated drinking water until 2013. We included subjects aged ≥20 years who provided two blood samples over an average 4-year interval (n = 8101). We examined the relationships between changes in PFOA, PFOS and PFHxS and changes in total cholesterol (TC), high-density lipoprotein cholesterol (HDLC) and low-density lipoprotein cholesterol (LDL-C). Linear models were fitted for change in the natural logarithm (ln) of each lipid in relation to the change in the ln of PFAS. From the estimated regression coefficients, we calculated the predicted percentage change in the response for a ln-decrease in PFAS serum concentrations. Results: Overall concentrations of PFOA, PFOS, PFHxS fell by 62.1 %, 24.4 % and 35.4 % from baseline, while small increases in lipids were observed. Declines in PFAS concentrations were associated with decreases in all lipids. For a ln-decrease in PFOA HDL-C decreased by 1.99 % (95 % CI: 1.28, 2.70), TC by 1.49 % (95 % CI: 0.88, 2.10), and LDL-C by 1.40 % (95 % CI: 0.45, 2.37). Conclusions: We found a positive association between changes in PFAS concentrations and changes in cholesterol levels, observing the most marked contrasts across sexes and age groups. Our findings support the reversibility of the associations identified in cross-sectional analyses, emphasizing the importance of water treatment measures in mitigating adverse health effects
Determinants of PFOA Serum Half-Life after End of Exposure: A Longitudinal Study on Highly Exposed Subjects in the Veneto Region
Background: Perfluoroalkyl substances (PFAS) are widely used, ubiquitous, and highly persistent man-made chemicals. Groundwater of a vast area of the Veneto Region (northeastern Italy) was found to be contaminated by PFAS from a manufacturing plant active since the late 1960s. As a result, residents were overexposed to PFAS through drinking water until 2013, mainly to perfluorooctanoic acid (PFOA). Objectives: The aim of the present study was to estimate the rates of decline in serum PFOA and their corresponding serum half-lives, while characterizing their determinants. Methods: We investigated 5,860 subjects more than 14 years of age who enrolled in the second surveillance round of the regional health surveillance program. Two blood samples were collected between 2017 and 2022 (average time between measurements: 4 years). Serum PFOA excretion rates and half-lives were estimated based on linear mixed effect models, modeling subject-specific serum PFOA concentrations over time and correcting for background concentrations. For modeling determinants of half-life [age, sex, body mass index (BMI), smoking-habit, alcohol consumption, and estimated glomerular filtration rate (eGFR)], we added interaction terms between each covariate and the elapsed time between measurements. Perfluorooctanesulfonate (PFOS) and perfluorohexanesulfonic acid (PFHxS) apparent half-lives were also estimated. A separate analysis was conducted in children (n=480). All analyses were stratified by sex. Results: Median initial serum concentrations of PFOA was 49 ng/mL (range: 0.5-1,090), with a median reduction of 62.45%. The mean estimated PFOA half-life was 2.36 years [95% confidence interval (CI): 2.33, 2.40], shorter in women (2.04; 95% CI: 2.00, 2.08) compared to men (2.83; 95% CI: 2.78, 2.89). Half-lives varied when stratified by some contributing factors, with faster excretion rates in nonsmokers and nonalcohol drinkers (especially in males). Conclusions: This study, to our knowledge the largest on PFOA half-life, provides precise estimates in young adults whose exposure via drinking water has largely ceased. For other PFAS, longer half-lives than reported in other studies can be explained by some ongoing exposure to PFAS via other routes. https://doi.org/10.1289/EHP13152
Perfluoroalkyl substance mixtures and cardio-metabolic outcomes in highly exposed male workers in the Veneto Region: A mixture-based approach
Background: Perfluoroalkyl substances (PFAS) have been consistently associated with cardio-metabolic traits. Occupational exposures to multiple PFAS with health outcomes have been poorly investigated. The aim of the present study was to examine these associations among former workers involved in PFAS production.Methods: We considered 232 male ex-employees who had worked in a factory (Trissino, Veneto Region, Italy), which produced PFAS and other chemicals during 1968-2018. Out of twelve serum PFAS, only four (PFOA, PFOS, PFHxS, and PFNA) were quantifiable in at least 50% of samples. Non-fasting serum total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured. The associations between serum PFAS mixture and considered outcomes were assessed through linear regression mixed models and Weighted Quantile Sum (WQS) regression, adjusting for potential confounders.Results: PFOA was detected at the highest level, with a median concentration (in ng/mL) of 80.8 (min-max: 0.35-13,033), followed by PFOS (median: 8.55, min-max: 0.35-343), PFHxS (median: 6.8, min-max: 0.35-597) and PFNA (median: 0.8, min-max: 0.35-5). We observed that each A quartile increase in the WQS index was positively associated with the levels of TC (beta: 8.41, 95% IC: 0.78-16.0), LDL-C (beta: 8.02, 95% IC: 1-15.0) and SBP (beta: 3.21, 95% IC: 0.82-5.60). No association of serum PFAS concentration on HDL cholesterol and DBP emerged. WQS analyses revealed a major contribution of PFNA and PFHxS for the cholesterol levels, although PFOA reported the highest concentration. PFOA and PFOS emerged as chemicals of concern regarding the association with SBP.Conclusions: The results showed a clear association between serum PFAS levels and markers of cardiovascular risk and support the importance of clinical surveillance of cardiovascular risk factors in population with a high exposure to PFAS, especially in the occupational setting
Going Beyond Counting First Authors in Author Co-citation Analysis
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
“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
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
Dispelling the Myths Behind First-author Citation Counts
We 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
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