1,721,150 research outputs found
PCR-DGGE DIFFERENTIATION OF SACCHAROMYCES SENSU STRICTO STRAINS
No full textA quick molecular biology method based on the polymerase chain reaction (PCR) and Denaturing Gradient Gel
Electrophoresis (DGGE) was developed for distinguishing strains belonging to the Saccharomyces sensu stricto
group. Differentiation was obtained between S. cerevisiae, S. paradoxus and S. bayanus/S. pastorianus although
no distinction was possible between S. bayanus and S. pastorianus using the amplification of the ITS regions. The
ability to distinguish between different strains of the Saccharomyces sensu stricto group could allow for a better
understanding of the ecology of these species on grapes as well as in musts and wines and the method developed
can be useful for the quick identification of Saccharomyces sensu stricto strains from numerous isolates
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
Biological Soil Crusts: A microenvironment affected by the microbial-secreted exopolysaccharidic matrix
No full textExtended abstract allegat
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
Different Environmental Applications Of Peptaibols
No full textPeptaibols ( a subgroup of peptaibiotics) (1) are a group of small peptides (2) characterized by short linear chain lengths (20 residues), C-terminal alcohol residues, and high levels of non-standard amino acids, principally-aminoisobutyric acid (Aib), isovaline (Iva), and the imino acid hydroxyproline (Hyp). Naturally occurring peptaibols have been isolated from soil fungi mostly from the genus Trichoderma (teleomorph Hypocrea) that is a group of filamentous ubiquist fungi in soil and they are capable of protecting crops from root-invading fungi, parasitizing mushrooms and other fungi, and in some instances being opportunistic human pathogens (3,4). Thus, these fungi occupy important roles in agriculture, medicine as well as industry (5,6).
In this work was tested the activity of secondary metabolites produced from Trichoderma harzianum (strain T-22) and Trichoderma asperellum (strain B1) either against typic phytopathogen agents of crops ( Rhizoctonia solani, Pythium ultimum and Fusarium oxysporum) or against fungi and bacteria colonies founded on the cultural heritage. In fact the bio-cleanig is a challenge and it is considered a promising alternative to synthetic pesticides. The antifungal and antimicrobial activities were performed by agar diffusion assay and the diameter of inhibition zones was measured and compared. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used for screening, identification and elucidation of amino acid sequences of peptaibols. These results open interesting perspectives on the possibility of using derivatives of fungal for the formulation of new commercial products can protect the plants and the environment.
These formulations have the advantage of being less harmful to the health of humans and animals, have no negative environmental impac
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