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Optimizing the development of seed-parent lines in hybrid rye breeding
No full textIn der Hybridroggenzüchtung werden Saat- und Pollenelterlinien aus zwei divergenten Formenkreisen entwickelt.
Zunächst wird auf Linieneigenleistung selektiert, anschließend auf Kombinationsfähigkeit zum anderen Formenkreis.
Hybridmechanismus ist die cytoplasmatisch-genische männliche Sterilität (CMS).
Thema der Arbeit sind Modellrechnungen zur Optimierung und Bewertung alternativer Schemata der Saatelterlinienentwicklung in der Hybridroggenzüchtung anhand ihres erwarteten Selektionsgewinns pro Jahr in einem die wichtigsten Zuchtziele umfassenden Selektionsindex.
Die Vorhersage der Selektionsgewinne basiert auf aktuellen Schätzwerten quantitativ-genetischer und ökonomischer Parameter.
Ermittelt wird die optimale Anzahl der Kandidaten, der Tester zur Erstellung der Testkreuzungen, der Prüforte und der Wiederholungen auf allen Selektionsstufen.
Die Optimierung erfolgt unter der Restriktion eines begrenzten Jahresbudgets.
Untersucht werden fünf Schemata, die sich bzgl. des Ausgangsmaterials, der Art der Testeinheiten, der Anzahl der Selektionsstufen und der Dauer unterscheiden.
Als Standard dient ein Second-Cycle-Schema, in dem zuerst die Eigenleistung von S2-Linien geprüft wird.
Die Selektion auf Kombinationsfähigkeit erfolgt dann in zwei Stufen an Testkreuzungen der CMS-Analogformen der Kandidaten in Rückkreuzungsgeneration BC1 bzw. BC2.
Das erste alternative Schema beinhaltet eine zusätzliche Stufe der BC1L-Testkreuzungsselektion.
Ein weiteres Schema ist geeignet zur Entwicklung von Saatelterlinien aus genetisch breiterem Populationsmaterial.
Darüberhinaus wurde die Verwendung von doppelhaploiden Linien untersucht sowie ein Schema, in dem Testkreuzungen mit Hilfe eines Gametozids anstelle der CMS erstellt werden.
Untersucht werden die optimale Dimensionierung und relative Vorzüglichkeit der Schemata für verschiedene genetische und ökonomische Situationen.
Zusätzliche praxisrelevante Kriterien werden diskutiert und Empfehlungen für die ZüchtuIn hybrid rye breeding, seed-parent and pollinator lines are developed from two divergent gene pools.
Line development comprises selection for line performance per se followed by selection for combining ability to the opposite gene pool.
Cytoplasmic-genic male sterility (CMS) is employed as hybridizing mechanism.
This study deals with model calculations aiming to optimize and compare alternative schemes of seed-parent line development in hybrid rye breeding on the basis of their expected selection gain per year in an index comprising the most important breeding objectives.
Prediction of selection gains rests on current estimates of quantitative-genetic and economic parameters.
The schemes are optimized for the number of candidates, testers to assess testcross performance, test locations, and replicates at the individual selection stages.
Optimization is carried out assuming a fixed annual budget.
Five schemes are investigated which differ in the basic genetic material assumed, in the type of test units and the number of selection stages for line and testcross selection, and in the length.
The standard scheme employs second cycle material. First, S2-lines are evaluated per se.
Selection for combining ability is then carried out at two stages employing testcross progenies of the CMS analogues of the candidate lines in backcross generations BC1 resp. BC2.
The first alternative scheme employs an additional stage of BC1L-testcross selection.
Another scheme is suited for developing seed-parent lines from broader-based population material.
In addition to these 'conventional' methods, a scheme using doubled haploid lines is investigated as well as a scheme in which testcross progenies are produced by means of a gametocide instead of CMS.
The optimum dimensioning and relative efficiency of the schemes is investigated for various genetical and economical situations
Optimizing the development of seed-parent lines in hybrid rye breeding
No full textIn hybrid rye breeding, seed-parent and pollinator lines are developed from two divergent gene pools.
Line development comprises selection for line performance per se followed by selection for combining ability to the opposite gene pool.
Cytoplasmic-genic male sterility (CMS) is employed as hybridizing mechanism.
This study deals with model calculations aiming to optimize and compare alternative schemes of seed-parent line development in hybrid rye breeding on the basis of their expected selection gain per year in an index comprising the most important breeding objectives.
Prediction of selection gains rests on current estimates of quantitative-genetic and economic parameters.
The schemes are optimized for the number of candidates, testers to assess testcross performance, test locations, and replicates at the individual selection stages.
Optimization is carried out assuming a fixed annual budget.
Five schemes are investigated which differ in the basic genetic material assumed, in the type of test units and the number of selection stages for line and testcross selection, and in the length.
The standard scheme employs second cycle material. First, S2-lines are evaluated per se.
Selection for combining ability is then carried out at two stages employing testcross progenies of the CMS analogues of the candidate lines in backcross generations BC1 resp. BC2.
The first alternative scheme employs an additional stage of BC1L-testcross selection.
Another scheme is suited for developing seed-parent lines from broader-based population material.
In addition to these 'conventional' methods, a scheme using doubled haploid lines is investigated as well as a scheme in which testcross progenies are produced by means of a gametocide instead of CMS.
The optimum dimensioning and relative efficiency of the schemes is investigated for various genetical and economical situations.In der Hybridroggenzüchtung werden Saat- und Pollenelterlinien aus zwei divergenten Formenkreisen entwickelt.
Zunächst wird auf Linieneigenleistung selektiert, anschließend auf Kombinationsfähigkeit zum anderen Formenkreis.
Hybridmechanismus ist die cytoplasmatisch-genische männliche Sterilität (CMS).
Thema der Arbeit sind Modellrechnungen zur Optimierung und Bewertung alternativer Schemata der Saatelterlinienentwicklung in der Hybridroggenzüchtung anhand ihres erwarteten Selektionsgewinns pro Jahr in einem die wichtigsten Zuchtziele umfassenden Selektionsindex.
Die Vorhersage der Selektionsgewinne basiert auf aktuellen Schätzwerten quantitativ-genetischer und ökonomischer Parameter.
Ermittelt wird die optimale Anzahl der Kandidaten, der Tester zur Erstellung der Testkreuzungen, der Prüforte und der Wiederholungen auf allen Selektionsstufen.
Die Optimierung erfolgt unter der Restriktion eines begrenzten Jahresbudgets.
Untersucht werden fünf Schemata, die sich bzgl. des Ausgangsmaterials, der Art der Testeinheiten, der Anzahl der Selektionsstufen und der Dauer unterscheiden.
Als Standard dient ein Second-Cycle-Schema, in dem zuerst die Eigenleistung von S2-Linien geprüft wird.
Die Selektion auf Kombinationsfähigkeit erfolgt dann in zwei Stufen an Testkreuzungen der CMS-Analogformen der Kandidaten in Rückkreuzungsgeneration BC1 bzw. BC2.
Das erste alternative Schema beinhaltet eine zusätzliche Stufe der BC1L-Testkreuzungsselektion.
Ein weiteres Schema ist geeignet zur Entwicklung von Saatelterlinien aus genetisch breiterem Populationsmaterial.
Darüberhinaus wurde die Verwendung von doppelhaploiden Linien untersucht sowie ein Schema, in dem Testkreuzungen mit Hilfe eines Gametozids anstelle der CMS erstellt werden.
Untersucht werden die optimale Dimensionierung und relative Vorzüglichkeit der Schemata für verschiedene genetische und ökonomische Situationen.
Zusätzliche praxisrelevante Kriterien werden diskutiert und Empfehlungen für die Zücht
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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