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Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Optimization of DNA extraction to detect Bacillus cereus from food using a PCR technique-
No full textBacillus species are extremely widespread in nature and may be isolated from soil, water, dust, air and many foods. The genus Bacillus is characterized by
the formation of heat resistant endospores. B. cereus has been recently considered as an ‘emerging’ food-borne pathogen. A couple of new primers (BCFW1 and
Bcrevnew) directed to identify B. cereus is described as well as protocols for optimization of DNA extraction for basic groups of food products which are particularly
prone to contain this microorganism. To avoid inhibitory effects exerted by particular food matrices, specific pre-extraction steps are recommended in this
work: a treatment with α-amylase from Aspergillus oryzae E.C. 3.2.1.1. (Sigma, Germany) for boiled rice or washing the pellet with EDTA solution for minced
meat, pasteurized milk and salads. The lowest possible level of detection was obtained for pasteurized milk (20 cells/g) and salad (30 cells/g) and it was comparable
with the results of classical microbiological analyses. Generally, for milk, salad and rice samples the limit of detection was close to 50 cells/g, whereas for
minced meat it was definitively higher (about 500 cells/g) and did not reflect results of performed standard plate counts. As the result of the studies, promising,
handy protocols for (i) an efficient DNA extraction from food matrices and (ii) fast, species-specific PCR identification were prepared and presented
Identificazione mediante PCR-DGGE dei batteri lattici alteranti la birra artigianale
No full textCraft beer is a not filtered and not pasteurized
product that maintains unalterated its
organoleptic characteristics. When compared
to industrial beers, it is more subjected to
microbial contamination that may be cause of
spoilage (turbidity, acidification, and production
of undesired aromatic compounds). The most
frequently found microorganisms in beer are
the Lactic Acid Bacteria (LAB), because of their
capability to survive at low pH and high levels
of ethanol. The aim of this work was to apply
the PCR-DGGE (Denaturing Gradient Gel
Electrophoresis) method to identify the bacteria
strains isolated from 23 beer samples, coming
from different microbreweries of the Friuli Venezia
Giulia region
Valutazione dei composti aromatici di birre ottenute con lieviti birrari ed enologici di alta e bassa fermentazione
No full textSelected yeasts, today, are employed in
the alcoholic beverage production to avoid
undesired fermentations and negative
aromatic compounds.
Yeast selection is made on the basis of
technological characteristics as fermentation
rate, level of worth attenuation, froth
formation, flocculation, resistance to the low
temperatures and alcohol and production of
aromatic compounds.
The aim of this work was to compare
different enological and brewing yeasts
for ale and lager fermentation to evaluate
the organoleptic and chemical profile of
aromatic compounds obtained from worth
fermentation
Identification of fresh water and marine fish species using molecular methods
No full textLabeling and traceability of fish has become an important matter due to the need of safety and quality of food. Identification of commercially important fish species commercialized in the European market by means of molecular methods is a valuable work in order to prevent fraudolent substitutions and to set up traceability plans. Recent methods of molecular biology allow the detection of regions of the genome characterized by a different mutation rates and mutations that do not change the amino acid sequence. In this study, the TGGE (Temperature Gradient Gel Electrophoresis) and RFLP (Restriction Fragment Lenght Polymorphism) methods were used to identify fresh-water and marine species which are commonly available in the italian fish markets
Application of PCR-DGGE for the identification of lactic acid bacteria in active dry wine yeasts
No full textAbstract - In this work a Polymerase Chain Reaction (PCR)-Denaturing Gradient Gel Electrophoresis (DGGE) protocol was used to identify
the Lactic Acid Bacteria (LAB) contaminants in enological active dry yeasts routinely used in the wine production. The method is
based on the PCR amplification of a DNA fragment from the region V1 of 16S rDNA gene followed by a DGGE technique. The main contaminant
was Lactobacillus spp. and Pediococcus spp
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