1,720,958 research outputs found
The genetic background modulates the intensity of Rpv3-dependent downy mildew resistance in grapevine
No full textGrape varieties with resistance to downy mildew (DM) carry alien chromosome segments in Vitis vinifera backgrounds. We previously showed that the largest descent group shares a non-vinifera haplotype at the locus Rpv3. Here, we performed a common garden experiment with 76 varieties to evaluate the level of field resistance across four years. All varieties exhibited effector-triggered immunity (ETI)-associated necrosis. On a scale of 1–9, the median OIV452 value for foliar resistance was 7.1 in the resistant lineage vs. 3.2 in vinifera controls. Genotype, year and their interaction significantly affected the level of resistance. Some resistant genotypes showed high mean values of OIV452 and low variance among years. Other resistant genotypes showed lower mean OIV452 and higher variance. They were capable of activating ETI, but the intensity was inadequate to restrict pathogen growth under highly conducive conditions. Rpv3-dependent responses were stronger in highly native genetic backgrounds and tended to attenuate in late backcross generations. Genetic backgrounds donated by European winegrapes of the convarietas occidentalis provided on average higher levels of Rpv3 resistance than backgrounds of orientalis table grapes
InDel markers for monitoring the introgression of downy mildew resistance from wild relatives into grape varieties
No full textWe identified haplotype-tagging insertion/deletions (InDels) for downy mildew resistance (Rpv3-1) in grapevine and converted them into InDel markers. InDel-25,941 and InDel-26,032 were validated by fragment analysis via capillary electrophoresis in 174 varieties of Vitis vinifera, 50 resistant varieties of the ‘Seibel 4614’ lineage that share Rpv3-1 by descent, and in 83 Vitis accessions. Amplicon sequencing of ancestral and derived alleles revealed that both mutations were caused by deletions. The 25,941-deletion is most likely recent. The derived allele is present only in resistant varieties obtained from ‘Seibel 4614’ and has originated in North American populations through two successive deletions within a predicted multiple stem-loop ssDNA structure, consisting of three nearby short inverted repeats, which shortened the ancestral DNA stepwise. The 26,032-deletion is more ancient. The derived allele is always present in resistant varieties of the ‘Seibel 4614’ lineage, completely absent from V. vinifera, not found in other North American accessions, and rarely present in Asian species. It may have originated in a common ancestral population before the continental disjunction, followed by incomplete lineage sorting, or in either lineage followed by introgression via secondary contacts. Genotyping with these markers does not require special instruments or chemistry for routine screening in breeding practice. Differences in amplicon size between grapes that carry or do not carry Rpv3-1 are detectable via standard agarose gel electrophoresis, or classical melting curve analysis using nonsaturating fluorescent dyes. The recombination rate between each marker and the trait locus is 0.118% for InDel-25,941 and 0.071% for InDel-26,032
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
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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