1,721,008 research outputs found
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
novel tyrosinase-based biosensor!
No full textPhenolic derivatives determination in medical, food and environmental samples is very important because of the high toxicity of these compounds. Currently used phenol detection methods are neither inexpensive nor rapid screening techniques.
Tyrosinase-based biosensors have been proven to be promising tools for this purpose because of advantages such as selectivity, low cost, fast and cheap screening of samples. Many materials, such as different polymers, alumina sol-gels, magnetic nanoparticles-chitosan nanocomposite, have been employed to immobilize tyrosinase in biosensors. These compounds were used in electrochemical biosensors and the enzyme was immobilized on the electrode surface.
Moreover orderly protein films on a solid support can be prepared using a layer-by-layer assembly, a simple process based on the sequential adsorption of polyanions and polycations guided by electrostatic interactions. Using this technique, we obtained a mushroom tyrosinase/poly(dimethyldiallylammonium chloride) multilayer on a quartz support.
The catecholase activity of the immobilized enzyme was detected using L-DOPA as substrate. Dopachrome formation was revealed at 475 nm. The kinetic parameters (Km and Vmax) of the tyrosinase were determined and compared with the behaviour of the enzyme in solution.
Our results demonstrate for the first time that “layer by layer” deposition preserves the enzymatic properties of tyrosinase. For this reason we propose this layering method as a useful potential tool for the production of a tyrosinase-based biosensor
Antibiotic resistance genes delivered by lactic Acid Bacteria isolated from ready to eat (RTE) food
No full textVariations 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
Identificazione dei leganti e dei pigmenti prelevati dalla Tomba della Badessa Ariperga (ex Convento di San Felice).
No full textLa definizione dei leganti e dei pigmenti presenti in una pellicola pittorica è di fondamentale importanza sia per la comprensione della tecnica impiegata dall'autore e per la sua collocazione storica, che per la definizione degli interventi da mettere in atto a scopo conservativo.
Nel presente lavoro viene identificata la composizione chimica di alcuni pigmenti prelevati dalla tomba della Badessa Ariperga (ex Convento di San Felice, Pavia) mediante differenti tecniche analitiche.
Dal confronto dei risultati ottenuti, mediante questo studio interdisciplinare, risulta che 1) i pigmenti sono delle «terre colorate» o Ocre; 2) attraverso il calcolo della formula minima, considerando come costituenti principali gli elementi determinati quantitativamente, si può dedurre con una ragionevole certezza il tipo di pigmento; 3) si può inoltre escludere la presenza di leganti nella pellicola pittorica esaminata. Pertanto si può a concludere che la tecnica impiegata dall'Autore nella realizzazione degli affreschi della tomba della Badessa Ariperga è quella del «buon fresco»
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