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MC1R gene: comparison between different farm animal species
Full text linkIl gene MC1R: confronto fra diverse specie animali di interesse zootecnico. Negli animali di interesse zootecnico, il polimorfismo del gene MC1R coinvolto nella pigmentazione è stato studiato a livello molecolare soltanto nell’ultimo decennio. Si sono confrontate descrizioni fenotipiche e polimorfismi del gene MC1R in alcune razze bovine (Rendena, Bruna, Cabannina, Ottonese-Varzese e Pezzata Rossa) e nel cavallo (62 animali). Tutti gli animali feomelanici sono portatori delle mutazioni recessive allo stato omozigote indipendentemente dalla tonalità del mantello. I cavalli neri sono portatori dell’allele selvatico del gene MC1R e della mutazione recessiva del gene ASIP allo stato omozigote. Nei cavalli bai e nelle altre razze bovine studiate è presente, almeno allo stato eterozigote, l’allele selvatico. Nella Bruna e nella Cabannina è presente anche l’allele E1. Nel gene MC1R, sequenziato in capre di razza Bionda dell’Adamello e Nera di Verzasca, si è evidenziata l’unica mutazione descritta in letteratura. I risultati sono stati confrontati con le informazioni disponibili nella specie murina e umana.Coat colour genes in farm animals have only been studied at molecular level over the last ten years, starting with Klungland et al. in 1995. Among the genes involved in pigmentation, MC1R, previously known as Extension locus, revealed polymorphisms related to red and black coat colour in different farm animal species. More exactly, the MelanoCortin-1 Receptor (MC1R) gene, specifically expressed in melanocytes, encodes for the homonymous G-protein coupled receptor involved in the regulation of the type of melanin synthesized. Melanocytes produce in fact two different types of melanins: the black or brown eumelanin and the yellow or red pheomelanin. The hair distribution of eu- and pheomelanins depends on the activity of MC1R, which is normally modulated by response to the melanocortin hormone, antagonized by the action of Agouti protein encoded by the ASIP gene. We previously studied the MC1R polymorphisms in some cattle reared in Italy (Crepaldi et al., 2003) and we now present the data on MC1R in other Italian cattle breeds, horses and goats. The aim of this work is to compare the pigmentary phenotypes and causative MC1R mutations in different farm animals and model species, such as mouse and human, in order to highlight differences and similarities between phenotypes and MC1R polymorphisms. The relationship between phenotypes and Agouti locus is also discussed
SNPs discovery in coat color genes for goats breeds traceability : a comparative approach
No full textComparison of coat color description and polymorphisms of MC1R, ASIP and TYRP1 genes in horses
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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
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