1,720,980 research outputs found
Green Strategies for the Cleaning of Works of Art Setting Up of an Analytical Protocol for the Evaluation of Cleaning
Full text linkIn last decades, the safety of both artworks and restorers during cleaning operations, has been the subject of many research works, aimed at the development of gel-systems that confine the solvent action to the very surface thus preventing its absorption into the paint layers and minimizing operators’ exposure.
In this research work, a totally sustainable approach has been presented for the cleaning of artworks. In particular new organogels made of bio-compatible components, were evaluated as cleaning tool for the removal of paint varnishes. The gels consist of a polymer derived from renewable bio-materials, poly(-3hydroxybutyrrate), and different green solvents (γ-valerolactone GVL, ethyl lactate EL, dimethyl carbonate DMC). These gels, previously characterized in order to investigate thermal and mechanical properties, were tested for the removal of natural and acrylic varnishes over different binding medium (linseed oil, egg and glue).The gels were first tested on painting mock-ups, not aged and aged, then validated on real paintings. Their cleaning capabilities were compared to methods traditionally employed in restoration (e.g. dimethyl sulfoxide, benzyl alcohol acetone, carbopol-gel). A specific protocol of cleaning evaluation was designed for assessing varnish removal capability, residues releasing and solvent retention by means of Optical Microscope observations of paint cross sections in visible and ultraviolet light, µFTIR-Attenuated Total Reflection surface analyses and Head Space-Solid Phase Micro Extraction coupled with GC-MS analyses. These new totally safe and biodegradable organogels demonstrated good varnish cleaning capabilities that, in conjunction with their easy preparation, use and waste, represent a “green” and safe approach for both paintings and painting restorers
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
Non-invasive identification of red and yellow oxide and sulfide pigments in wall-paintings with portable ER-FTIR spectroscopy
No full textScientific interest in analytical tools that enable reliable, repeatable, and rapid measurements without sampling is growing in the field of cultural heritage. Therefore, improving the use of methods that permit an efficient characterization of a wide range of materials through non-invasive and portable instruments, such as spectroscopies, is currently in high demand. This work is focused on the non-invasive study and identification of selected red and yellow pigments containing oxides and sulfides, frequently used in ancient wall-paintings, by means of portable External Reflectance Fourier Transform Infrared spectroscopy (ER-FTIR) within an extended spectral range (7500 - 360 cm−1) which includes a portion of far IR addressing diagnostic peaks and band assignment for the first time. In this work we have also examined the reflection signals of the pigments when applied on a surface representing a fresco wall-painting, to discuss possible changes of the profile as the optical and morphological properties of the surface change. For this purpose, yellow and red oxides, ochres, Siennas, minium, orpiment, and vermillion were selected and used to produce laboratory mock-ups of fresco paints. The ER-FTIR signals obtained on raw pigments were firstly validated by portable non-invasive Raman spectroscopy and X-Ray Fluorescence, and bench-top X-Ray powder Diffraction. Then, the results were subsequently compared with the ER-FTIR signals collected on the mock-ups to discuss the changes in the reflection spectral profile when in presence of rough surfaces and matrix-effects. The combined study on reference materials and mock-ups allowed to identify and discuss ER-FTIR marker bands which were finally validated on real samples of three fragments of Roman frescos provided by the Archeological Museum “San Lorenzo” in Cremona. The proposed method demonstrates distinctive IR features from external reflection analysis on the selected pigments, scarcely studied by portable FTIR instruments, offering a decisive advancement for in situ analytical characterization of the pigments used in wall-paintings
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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