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Airways acidification in asthma studied by means of induced sputum: a study of feasibility and correlation with disease control and severity
No full textTechnical practices are important to consider when assessing noninvasive ventilation failure (multiple letters)
No full textAn investigation of airway acidification in asthma using induced sputum: A study of feasibility and correlation
No full textRATIONALE:
Acidification of the airways seems to be involved in asthma pathophysiology, but its assessment might be difficult.
OBJECTIVES:
The aim of our study is to assess the feasibility and validity of airway acidification measurement by induced sputum and its clinical significance in asthma.
METHODS:
Induced-sputum samples were obtained in 57 outpatients with asthma. The between-sample repeatability after 48 hours was measured in an independent population of 14 patients with asthma. pH was measured using a pH meter. The control of asthma was established by the Asthma Control Questionnaire.
MEASUREMENTS AND MAIN RESULTS:
The pH measurement was feasible in all samples and repeatable both within (intraclass correlation coefficient [ICC], 0.96) and between samples (ICC, 0.621). The mean pH was significantly different between healthy subjects and patients with asthma, including in those with controlled (mean pH: 7.54 in healthy subjects vs. 7.28 in subjects with controlled asthma; p = 0.0105) and uncontrolled disease (mean pH: 7.54 in healthy subjects vs. 7.06 in subjects with uncontrolled disease; p < 0.0001), and between patients with stable asthma and those with poorly controlled asthma (7.28 vs. 7.06, respectively; p = 0.0134). The validity of the method was assessed with the receiver operating characteristic curves and induced-sputum lower pH values (with a cutoff value of 7.3; sensitivity, 72.1%; specificity, 100%).
CONCLUSIONS:
Patients with asthma show lower pH than healthy subjects. Patients with poorly controlled asthma seem to have the lowest induced-sputum pH, independent of the GINA (Global Initiative for Asthma) severity level. In conclusion, induced sputum is a feasible, repeatable, noninvasive method to measure airway pH. The pH in induced sputum may reflect a different aspect of asthma from sputum eosinophils and be related to different pathophysiologic 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
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