1,720,959 research outputs found
Dependence of calibration sensitivity of a polysulfone/Ru(II)-Tris(4,7-diphenyl-1,10-phenanthroline)-based oxygen optical sensor on its structural parameters
No full textThe optimum performance of an optical oxygen sensor based on polysulfone (PSF)/[Ru(II)-
Tris(4,7-diphenyl-1,10-phenanthroline)] octylsulfonate (Ru(dpp)OS) was checked by carefully
tuning the parameters affecting the membrane preparation. In particular, membranes
having thickness ranging between 0.2 and 8.0 μm with various luminophore concentrations
were prepared by dip-coating and tested. The membrane thickness was controlled
by tuning the solution viscosity, and was measured both by secondary ion mass spectrometry
(SIMS) and by visible spectroscopy (Vis). Luminescence-quenching-based calibration
was a single value of the Stern–Volmer constant (KSV) for membranes containing up to
20 mmol Ru(dpp) g−1 PSF (1.35 μm average thickness). The KSV value decreased for larger concentration.
The highest sensitivity was obtained with membrane thickness around 1.6 μm,
having a response time close to 1 s. Thicker membranes exhibited an emission saturation
effect and were characterized by longer response time. The KSV behavior was interpreted on
the basis of a mathematical approach accounting for the contribution of luminescence lifetime, oxygen diffusion coefficient (DO2 ) and oxygen solubility inside the membrane (sO2 )
establishing the role of all of them and allowing their experimental determination. Moreover,
a simple experimental way to estimate KSV without needing calibration was proposed.
It was based either on the light emission asymmetry or on the percent variation of light
emission on passing from pure nitrogen to pure oxygen
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
La grande vetrata di SS. Giovanni e Paolo: rilievo e studio del degrado vitreo e del dissesto statico
No full text“Grandioso finestrone archiacuto a comparti, con magnifica vetrata quattrocentesca, dai meravigliosi smalti colorati. Sebbene molto restaurata, è una delle opere più insigni uscite dalle
fornaci muranesi” (Grand compartmented ogival window, with magnificent fifteenth-century stained-glass, decorated with amazing coloured enamels. Even though much restored, it is one of the most eminent artworks produced in Murano furnaces). Such description given by Lorenzetti [1], sets the features of the Grande Vetrata of the SS. Giovanni e Paolo Church in Venice and above all, it considers every single part of which this marvellous work of art is constituted. These different parts are: the stone frame in which the stained-glass window is allocated, the stained-glass window itself (made up of 66 panels), and the grisaille used to decorate the glass tesserae.
Looking at the precedent restoration works [2], it has been seen that the problem of the stone wall consolidation arose also in the past. Such a problem, however, was always considered second place as to the grisaille consolidation and to the image conservation.
A close up analysis of the artefact was made and all the weathering phenomena were documented.
The documentation was carried out for every constituent of the work of art (glass tesserae, metallic retaining structures and stone wall) and particular attention was given to their interactions (i.e. the consequences of the wall movement on the stained-glass window). The diagnostic work was conducted at different stages: characterization of the Building,
Technological and Decorative Apparatus; analysis of their weathering and comparison of the data related to each apparatus. The restoration project will have to aim to the consolidation and integration of the grisailles, where
it will be necessary, but the consolidation of the stone wall and the rectification of the panels’ deformation will not have to be relegated to the second place
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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