1,720,986 research outputs found
Breath analysis: trends in techniques and clinical applications
No full textOver the last few years, breath analysis for the routine monitoring either of metabolic disorders caused by specific diseases or occupational exposure to toxic substances has become more and more attractive due to its noninvasiveness.
Several approaches have been proposed for sample collection, treatment, and analysis. This paper gives a critical overview of the analytical devices and procedures used for breath analysis. Results on the identification of chemicals in human breath for a selection of diseases are discussed
Caratterizzazione chimica dell'espirato umano in pazienti affetti da diabete mediante GC/MS
No full text
Advances in clinical application of breath analysis by gas chromatography/mass spectrometry
No full text
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
Monitoring breath during oral glucose tolerance tests
No full textThe evolution of breath composition during oral glucose tolerance tests (OGTTs) was analysed
by thermal desorption/gas chromatography/mass spectrometry in 16 subjects and correlated
to blood glucose levels. The glucose tolerance tests classified five of the subjects as diabetics,
eight as affected by impaired glucose tolerance and three as normoglycaemic. Acetone levels
were generally higher in diabetics (average concentration values: diabetics, 300 ± 40 ppbv;
impaired glucose tolerance, 350 ± 30 ppbv; normoglycaemic, 230 ± 20 ppbv) but the large
inter-individual variability did not allow us to identify the three groups by this parameter
alone. The exhalation of 3-hydroxy-butan-2-one and butane-2,3-dione, likely due to the
metabolization of glucose by bacteria in the mouth, was also observed. Future work will
involve the extension of the analyses to other volatile compounds by attempting to improve the
level of discrimination between the various classes of subjects
- …
