1,721,053 research outputs found
Potentials of biodiversity in chickens
No full textWithin the framework of the Synbreed project, a large panel of chicken breeds were phenotypically characterized encompassing both categorical traits and body measurements. This "Synbreed Chicken Biodiversity Panel (SCBP)" comprises more than 2400 individuals from 111 diverse breeds and colour variants of various geographical origins including two wild jungle fowl populations and commercial purebred lines. In this study, data of 1967 individuals genotyped at more than 445'000 SNP loci using the Affymetrix 600k Axiom chicken SNP Array were available. Genome wide association analyses clearly detected genomic regions of known mutations for yellow skin colour and rose-comb, respectively. In addition, a cluster analysis with a subset of 89 populations using an extract of autosomal SNPs variable in the wild ancestor Red Jungle Fowl was conducted to visualize the relationship between breeds. Results showed that the majority of breeds formed clusters according to their supposed relationships. The SCBP represents a valuable resource for high resolution analysis of genetic diversity and mapping of genomic regions underlying phenotypic variability
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
Potentials of biodiversity in chickens
No full textWithin the framework of the Synbreed project, a large panel of chicken breeds were phenotypically characterized encompassing both categorical traits and body measurements. This "Synbreed Chicken Biodiversity Panel (SCBP)" comprises more than 2400 individuals from 111 diverse breeds and colour variants of various geographical origins including two wild jungle fowl populations and commercial purebred lines. In this study, data of 1967 individuals genotyped at more than 445'000 SNP loci using the Affymetrix 600k Axiom chicken SNP Array were available. Genome wide association analyses clearly detected genomic regions of known mutations for yellow skin colour and rose-comb, respectively. In addition, a cluster analysis with a subset of 89 populations using an extract of autosomal SNPs variable in the wild ancestor Red Jungle Fowl was conducted to visualize the relationship between breeds. Results showed that the majority of breeds formed clusters according to their supposed relationships. The SCBP represents a valuable resource for high resolution analysis of genetic diversity and mapping of genomic regions underlying phenotypic variability
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
Evaluation of inbreeding in laying hens by applying optimum genetic contribution and gene flow theory
No full textDue to consistent increases of inbreeding of on average 0.95% per generation in layer populations, selection tools should consider both genetic gain and genetic relationships in the long term. The optimum genetic contribution theory using official estimated breeding values for egg production was applied for 3 different lines of a layer breeding program to find the optimal allocations of hens and sires. Constraints in different scenarios encompassed restrictions related to additive genetic relationships, the increase of inbreeding, the number of selected sires and hens, and the number of selected offspring per mating. All these constraints enabled higher genetic gain up to 10.9% at the same level of additive genetic relationships or in lower relationships at the same gain when compared with conventional selection schemes ignoring relationships. Increases of inbreeding and genetic gain were associated with the number of selected sires. For the lowest level of the allowed average relationship at 10%, the optimal number of sires was 70 and the estimated breeding value for egg production of the selected group was 127.9. At the highest relationship constraint (16%), the optimal number of sires decreased to 15, and the average genetic value increased to 139.7. Contributions from selected sires and hens were used to develop specific mating plans to minimize inbreeding in the following generation by applying a simulated annealing algorithm. The additional reduction of average additive genetic relationships for matings was up to 44.9%. An innovative deterministic approach to estimate kinship coefficients between and within defined selection groups based on gene flow theory was applied to compare increases of inbreeding from random matings with layer populations undergoing selection. Large differences in rates of inbreeding were found, and they underline the necessity to establish selection tools controlling long-term relationships. Furthermore, it was suggested to use optimum genetic contribution theory for conservation schemes or, for example, the experimental line in our study.German Ministry of Education and Research (BMBF); Lohmann Tierzucht Gmb
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
Genetic approach to select against embryo mortality caused by Enterococcus faecalis infection in laying hens
No full textDispelling 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
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