1,721,198 research outputs found
The influence of early exposures on incidence and remission of asthma throughtout life
No full textBACKGROUND: Knowledge of the effects of early environmental and congenital factors on the natural history of asthma may provide important clues to the pathogenesis of asthma.
OBJECTIVE: We assessed associations between potential, early determinants and the incidence and remission of asthma throughout life, and tested whether the strength and direction of these associations varied in childhood, adolescence, and adulthood.
METHODS: The data pertaining to the individual asthma history of 18,156 subjects, age 0 to 44 years, who attended the clinical stage of the European Community Respiratory Health Survey were analyzed retrospectively by life-event methods. Onset of asthma was defined as age at the first attack, and asthmatic patients were considered to be in remission if they had not been under treatment or had an attack of asthma in the past 24 months. Onset and remission were evaluated in 3 time windows: or =20 years of age. The associations of asthma with early determinants were estimated by hazard ratios (HRs).
RESULTS: A family history of asthma or allergy was associated with a higher risk of developing asthma (HR, 1.89; 95% CI, 1.67-2.13) and a lower chance of remission (HR, 0.79; 95% CI, 0.64-0.99) throughout life. No matter what one's genetic predisposition was, early, acute respiratory infections were associated with an increased lifelong risk of asthma onset (pooled HR, 3.19; 95% CI, 2.75-3.69), whereas early contact with older children, which is a marker of prolonged, intermittent exposure to infectious agents, conferred permanent protection against asthma (HR, 0.84; 95% CI, 0.74-0.96) and increased the chance of remission in childhood asthma (HR, 1.50; 95% CI, 1.10-2.04). Pet ownership had a protective effect only in childhood (HR, 0.78; 95% CI, 0.74-0.96), whereas maternal smoking did not show a significant association with asthma. Female sex was negatively associated with the onset of asthma in childhood (HR, 0.62; 95% CI, 0.52-0.75) and positively in adulthood (HR, 2.01; 95% CI, 1.61-2.51). The pattern of associations was similar in sensitized (positive assay to specific IgE) and nonsensitized asthmatic patients.
CONCLUSION: Genetic predisposition and exposure to infectious agents are major early determinants that influence a subsequent history of asthma. The length and type of exposure to infectious agents seem able either to promote or to suppress an anti-inflammatory process, unrelated to IgE, which can partially interfere with an acquired predisposition for asthma
The role of smoking in allergy and asthma: lessons from the ECRHS
No full textThe European Community Respiratory HealthSurvey is an international multicenter cohort study of asthma,allergy, and lung function that began in the early-1990swith recruitment of population-based samples of 20- to 44-year-old adults, mainly in Europe. The aims of the study arebroad ranging but include assessment of the role of in uteroexposure to tobacco smoke, exposure to environmental tobaccosmoke, and active smoking on the incidence, prevalence,and prognosis of allergy and asthma. Cross-sectionaland longitudinal analyses looking at these associations havebeen conducted, sometimes only using information collectedin one country, and on other occasions using informationcollected in all the participating centers. This article summarizesthe results from these various publications from thislarge epidemiologic study
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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