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Genotyping measures and population genetic indices for assesing reproductive modes of polyploid Ludwigia grandiflora subsp. hexapetala in western Europe
No full text<p>Raw data used to assess reproductive modes in 53 sampled populations in western Europe (France and northern Spain).</p><p><i>Ludwigia grandiflora </i>subsp.<i> hexapetala</i> (<i>Lgh</i>) is a hermaphrodite, polyploid, partially clonal and heteromorphic plant that recently colonized multiple countries worldwide. Individuals in this species are either self-incompatible caused by a late-acting self-incompatible (LSI) system developing long-styled flowers, or self-compatible (SC) developing short-styled flowers. We used a SNP approach allowing confident allele dosage to genotype 53 LSI and SC populations of <i>Lgh</i> in France and northern Spain. We measured their genetic diversity and assessed their reproductive modes using methods adapted to autopolyploid species. </p>
Reproductive system, polyploidy and genetic diversity of Ludwigia grandiflora subsp hexapetala invasive populations in France
No full textDans un contexte de succès de colonisation des espèces invasives, la compréhension d’un front d’invasion est essentielle afin d’identifier des leviers de gestion. En France, Ludwigia grandiflora subsp hexapetala a envahi la plupart de réseaux hydrographiques avec des populations fertiles et stériles. Les objectifs de cette thèse étaient l’identification des facteurs influençant sa reproduction sexuée et la caractérisation de sa diversité génétique afin d’inférer le mode de reproduction efficace et de comprendre l’histoire du front d’invasion. La biologie florale et la fructification des populations fertiles et stériles dans différentes conditions climatiques et après différents croisements contrôlés ainsi que la diversité génétique des populations via un set de marqueurs moléculaires SNP ont été évaluées,Ces travaux ont montré que la reproduction sexuée de Ludwigia grandiflora subsp hexapetala est sous contrôle d’un système d’auto-incompatibilité hétéromorphique « à action tardive » de type distyle-homostyle. Nous avons identifié deux fronts d’invasion avec deux points de rencontre. Le système de reproduction efficace majoritaire est la clonalité avec un signal d’allogamie au niveau des 2 « hot-spot » de diversité, suggérant une priorisation de gestion à leurs niveaux. Ces études pourront être étendues à d’autres fronts d’invasion en Europe et aux USA.In a context of successful colonization of invasive species, understanding of an invasion front is essential in order to identify management levers. In France, Ludwigia grandiflora subsp hexapetala has invaded most river systems with fertile and sterile populations. The objectives of this thesis were the identification of factors influencing its sexual reproduction and the characterisation of its genetic diversity in order to infer the efficient mode of reproduction and to understand the history of the invasion front.Floral biology and fructification of fertile and sterile populations in different climatic conditions and after different controlled crosses as well as the genetic diversity of the populations via a set of SNP molecular markers were evaluated. These studied showed that the sexual reproduction of Ludwigia grandiflora subsp hexapetala is under the control of a "late-acting" heteromorphic self-incompatibility system of the distyle-homostyle type. We have identified two invasion fronts with two meeting points. The majority efficient breeding system is clonality with an allogamy signal at the level of the 2 diversity hot spots, suggesting management prioritization at their levels. These studies could be extended to other invasion fronts in Europe and the USA
Système de reproduction, polyploïdie et diversité génétique des populations invasives de Ludwigia grandiflora subsp hexapetala en France
No full textIn a context of successful colonization of invasive species, understanding of an invasion front is essential in order to identify management levers. In France, Ludwigia grandiflora subsp hexapetala has invaded most river systems with fertile and sterile populations. The objectives of this thesis were the identification of factors influencing its sexual reproduction and the characterisation of its genetic diversity in order to infer the efficient mode of reproduction and to understand the history of the invasion front.Floral biology and fructification of fertile and sterile populations in different climatic conditions and after different controlled crosses as well as the genetic diversity of the populations via a set of SNP molecular markers were evaluated. These studied showed that the sexual reproduction of Ludwigia grandiflora subsp hexapetala is under the control of a "late-acting" heteromorphic self-incompatibility system of the distyle-homostyle type. We have identified two invasion fronts with two meeting points. The majority efficient breeding system is clonality with an allogamy signal at the level of the 2 diversity hot spots, suggesting management prioritization at their levels. These studies could be extended to other invasion fronts in Europe and the USA.Dans un contexte de succès de colonisation des espèces invasives, la compréhension d’un front d’invasion est essentielle afin d’identifier des leviers de gestion. En France, Ludwigia grandiflora subsp hexapetala a envahi la plupart de réseaux hydrographiques avec des populations fertiles et stériles. Les objectifs de cette thèse étaient l’identification des facteurs influençant sa reproduction sexuée et la caractérisation de sa diversité génétique afin d’inférer le mode de reproduction efficace et de comprendre l’histoire du front d’invasion. La biologie florale et la fructification des populations fertiles et stériles dans différentes conditions climatiques et après différents croisements contrôlés ainsi que la diversité génétique des populations via un set de marqueurs moléculaires SNP ont été évaluées,Ces travaux ont montré que la reproduction sexuée de Ludwigia grandiflora subsp hexapetala est sous contrôle d’un système d’auto-incompatibilité hétéromorphique « à action tardive » de type distyle-homostyle. Nous avons identifié deux fronts d’invasion avec deux points de rencontre. Le système de reproduction efficace majoritaire est la clonalité avec un signal d’allogamie au niveau des 2 « hot-spot » de diversité, suggérant une priorisation de gestion à leurs niveaux. Ces études pourront être étendues à d’autres fronts d’invasion en Europe et aux USA
Système de reproduction, polyploïdie et diversité génétique des populations invasives de Ludwigia grandiflora subsp hexapetala en France
No full textIn a context of successful colonization of invasive species, understanding of an invasion front is essential in order to identify management levers. In France, Ludwigia grandiflora subsp hexapetala has invaded most river systems with fertile and sterile populations. The objectives of this thesis were the identification of factors influencing its sexual reproduction and the characterisation of its genetic diversity in order to infer the efficient mode of reproduction and to understand the history of the invasion front.Floral biology and fructification of fertile and sterile populations in different climatic conditions and after different controlled crosses as well as the genetic diversity of the populations via a set of SNP molecular markers were evaluated. These studied showed that the sexual reproduction of Ludwigia grandiflora subsp hexapetala is under the control of a "late-acting" heteromorphic self-incompatibility system of the distyle-homostyle type. We have identified two invasion fronts with two meeting points. The majority efficient breeding system is clonality with an allogamy signal at the level of the 2 diversity hot spots, suggesting management prioritization at their levels. These studies could be extended to other invasion fronts in Europe and the USA.Dans un contexte de succès de colonisation des espèces invasives, la compréhension d’un front d’invasion est essentielle afin d’identifier des leviers de gestion. En France, Ludwigia grandiflora subsp hexapetala a envahi la plupart de réseaux hydrographiques avec des populations fertiles et stériles. Les objectifs de cette thèse étaient l’identification des facteurs influençant sa reproduction sexuée et la caractérisation de sa diversité génétique afin d’inférer le mode de reproduction efficace et de comprendre l’histoire du front d’invasion. La biologie florale et la fructification des populations fertiles et stériles dans différentes conditions climatiques et après différents croisements contrôlés ainsi que la diversité génétique des populations via un set de marqueurs moléculaires SNP ont été évaluées,Ces travaux ont montré que la reproduction sexuée de Ludwigia grandiflora subsp hexapetala est sous contrôle d’un système d’auto-incompatibilité hétéromorphique « à action tardive » de type distyle-homostyle. Nous avons identifié deux fronts d’invasion avec deux points de rencontre. Le système de reproduction efficace majoritaire est la clonalité avec un signal d’allogamie au niveau des 2 « hot-spot » de diversité, suggérant une priorisation de gestion à leurs niveaux. Ces études pourront être étendues à d’autres fronts d’invasion en Europe et aux USA
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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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