1,721,012 research outputs found
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
Quantitative Real-time PCR Analysis of Tobacco mosaic virus in Individual Flue-cured Tobacco Seed
No full textThe Tobacco mosaic virus (TMV) has infected tobacco plants since the late 1800’s, causing detrimental yield and economic losses in tobacco. TMV is classified as a seed borne virus because the virus infects tobacco seed as a contaminant on the seed coat surface. The purpose of this study is to investigate seed-borne transmission of Tobacco mosaic virus (TMV) by examining the infestation route of tobacco seeds. Four different crosses were performed using K326 flue-cured variety: 1) self-fertilized, TMV infected, 2) self-fertilized, non-TMV infected, 3) TMV maternal infected, and 4) TMV paternal infected. Tobacco seeds were collected from three individual pods for each cross. Total RNA was extracted from 100 individual seeds per pod, and synthesized into cDNA for analysis. A quantitative real-time PCR (qRT-PCR) assay was developed to analyze TMV concentrations within individual tobacco seeds. qRT-PCR was adopted over other traditional viral detection methods for its capability of generating fast quantitative results in real time. Results revealed distinct TMV concentration patterns and data suggests uneven distribution of TMV within individual seed pods. These results show evidence of maternal but not paternal seed-borne transmission of TMV. Furthermore, dissection of individual seed reveals that the majority of TMV found in the seed is located within the seed coat and not the embryo. These findings may be useful in identifying the TMV infection route of entry in emerging tobacco seedlings.MAL
Impact of Nitrogen Fertilization Rate on Cured Leaf Quality and Chemistry of Flue-Cured Tobacco
No full textProper nitrogen fertilization is important for both yield and cured leaf quality of flue-cured
tobacco. Optimizing the yield of high-quality tobacco is critical for grower profitability. A field
study was conducted at the Virginia Tech Southern Piedmont Center near Blackstone, Virginia to
investigate the relationship between nitrogen (N) fertilization rate and the yield and quality of
flue-cured tobacco. Six varieties were evaluated at N rates of 62, 72, 82, and 92 lbs. per acre.
Petiole sap nitrate levels tested at topping time were correlated with increasing N fertilization
rates. Nitrate levels measured in the cured tobacco were significantly higher with 82 and 92 N
rates indicating a negative effect on proper leaf ripening. No response was observed for cured
leaf yield to N fertilization rate. However, cured leaf quality was adversely impacted by 82 and
92 lbs. per acre of N. Results of this field test emphasize that proper N fertilization is critical for
cured leaf quality and has a direct impact to the marketability of the tobacco and, ultimately,
grower profitability.MAL
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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