1,720,981 research outputs found
Development of blast-resistant rice variety derived from crossing between MR219 and Pongsu Seribu 1 through marker-assisted selection
Full text linkMarker-assisted selection (MAS) is very effective and powerful method for efficient selection of the target gene. MAS can potentially accelerate breeding programs for varietal resistance. Marker-assisted backcrossing (MABC) is the most-effective way of transferring specific gene(s) to an agronomically superior variety. Rice blast disease, caused by the fungus Magnaporthe oryza, is one of the most devastating and destructive disease causing significant yield loss worldwide as well as Malaysia. The most-effective approach to preventing this disease is the genetic improvement using resistant varieties. In this study, blast resistance gene (putative Piz) was transferred from an indica rice donor Pongsu Seribu 1, using MABC method, into a blast susceptible elite indica rice variety, MR219. Therefore, a cross between rice variety MR219 and Pongsu Seribu 1 was performed to incorporate blast resistance gene(s) into MR219 variety without losing their quality. Sixteen microsatellite markers tightly linked to the blast resistant genes were selected and used in this study to determine potential association with blast resistance gene. These polymorphic foreground markers were used for confirmation of blast resistant genes in F1 population. After that only two microsatellite markers, RM6836 and RM8225, that conferred blast resistance gene (putative Piz) located on chromosome 6 were used to BC1F1, BC2F1 and BC2F2 populations related to resistance against the most-virulent Malaysian rice blast pathotype P7.2 of Magnaporthe oryzae. Out of 375-microsatellite markers, 70 markers were found to have polymorphism between the parental lines and were used for background analysis in each generation. The inheritance of the resistance gene against the pathotype P7.2 was investigated on BC2F1 and BC2F2 populations. The parent MR219 showed susceptible reaction with lesion score 5 to 7, whereas Pongsu Seribu 1 was found as resistant producing lesion score 0 to 2 after exposing to P7.2 inoculum in the glasshouse. In BC2F1 population, 333 plants were challenged with pathotype P7.2. Among them, 159 plants showed resistant reaction and another 174 plants showed susceptible reaction to blast. The observed frequencies were tested for goodness of fit with chi-square (χ2) test for single dominant gene model. The goodness of fit (p=0.4463) to the expected test cross ratio (1:1) showed that the resistance is controlled by a single nuclear gene. The plants resistant to blast pathotype P7.2 from BC2F1 population showed good fit with two markers, RM6836 (χ2=0.20; p=0.6547) and RM8225 (χ2=1.20; p=0.2733) with expected test cross ratio (1:1) for single gene model. These two markers were found suitable for marker-assisted selection conferring blast resistance gene against the pathotype P7.2. The phenotypic reaction on the blast incidence of BC2F2 population segregated in 3:1 ratio (resistance to susceptible). The genotypic segregation of BC2F2 population using RM6836 and RM8225 markers showed 1:2:1 ratio. Results confirmed that single dominant gene governs blast resistance in Pongsu Seribu 1 variety. The background analysis of the improved lines indicated recurrent parent genome recovery ranging from 75.40 % to 91.30 % in BC1F1, 80.40% to 96.70% in BC2F1 and 92.7% to 97.7% in BC2F2 generation. The average proportion of the recurrent parent in BC2F2 selected improved lines was 95.98%, explaining the very close similarity at phenotypic level with the parental variety, MR219. Thirteen homozygous plants consist of blast resistant gene which is phenotypically similar with MR219 backgrounds were selected as an improved blast resistant breeding lines. The agronomic characters showed no significant difference between MR219-parent and blast resistant MR219 improved lines. The improved lines possessing blast resistant gene (putative Piz) with desirable agronomic traits that can be used as a valuable source for further blast resistance rice breeding programs. In conclusion, from this research rice blast resistance in Pongsu Seribu 1 is governed by a single dominant gene located on chromosome 6, which is linked to RM6836 and RM8225 markers. This information could be used in MAS for blast resistance in other rice crosses involving Pongsu Seribu 1
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
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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