1,720,960 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
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
Plastizität und genetische Variation entlang von Höhen- und Breitengradienten: Erkenntnisse aus der weit verbreiteten Pflanze Anthyllis vulneraria
No full textThe distribution and population characteristics of plants are largely influenced by the environmental conditions they encounter across their ranges. In response to environmental changes, populations can migrate to new locations, exhibit phenotypic plasticity and undergo evolutionary adaptation. Studies comparing population traits along gradients of elevation and latitude provide an opportunity to assess the influence of different environmental and historical factors on plant population characteristics. To investigate plant plasticity and evolutionary potential in response to environmental variation, I employed an integrative approach combining field surveys, population genetic studies, and experiments. The widespread plant Anthyllis vulneraria was selected as a model species because of its large elevational and latitudinal distribution in Europe. In particular, I studied across elevational and latitudinal gradients (1) the characteristics of habitats and populations of A. vulneraria, (2) the neutral molecular genetic diversity and differentiation of populations, (3) the quantitative genetic differentiation and the evolutionary potential of populations. The elevational gradient in the Alps ranged from 500 m to the elevational limit at 2500 m and the latitudinal gradient spanned 2400 km from Central Europe to the range limit in the North. The length of the two gradients was chosen to correspond to a change of c. 11.5 °C in annual mean temperature.
I explored the habitat characteristics of 40 populations of A. vulneraria along both the elevational and latitudinal gradients and studied their influence on population characteristics. Plant size and reproduction decreased, but plant density increased with elevation and latitude, indicating higher recruitment and demographic compensation among vital rates. The results support the view that demographic compensation may be common in widespread species. Temperature variation along both gradients was found to have the strongest effects on population characteristics, followed by differences in precipitation, solar radiation, and soil nutrients. The proportion of plants flowering, seed set and seed mass declined with latitude indicating resource limitation and reduced pollination in the North, while the strong variation in these traits along the elevational gradient was not related to elevation or other covarying environmental variables, but to local environmental variation in alpine habitats.
I examined the molecular genetic diversity and differentiation of the populations of A. vulneraria using microsatellites, which are considered to be neutral markers and unaffected by natural selection. Genetic diversity strongly declined and differentiation increased with latitude. These patterns are likely the outcome of serial founder effects during the northward colonization following glacier retreat after the last ice age. The genetic diversity and differentiation among populations of A. vulneraria was not related to elevation. This observation could be attributed to the higher gene flow facilitated by the much shorter elevational gradient. However, I found evidence of isolation by distance along both gradients, indicating restricted gene flow among populations along both gradients. Subarctic populations differed genetically from alpine populations indicating that the northern populations did not originate from high elevational ones in the Alps.
Plants grown from seeds originating from the studied populations were studied in a common garden experiment to assess the quantitative genetic differentiation and phenotypic plasticity of populations along the elevational and latitudinal gradients and to investigate their evolutionary potential. Most traits measured in the common garden exhibited clinal variation with elevation and latitude of origin indicating adaptive differentiation of traits along the gradients. Divergent selection was indicated by higher QST-values (measuring quantitative genetic differentiation) than FST-values (measuring neutral molecular genetic differentiation) in some traits. Furthermore, I observed that the differences in performance between mothers and their progeny were smaller for populations from high elevations and latitudes, suggesting reduced plasticity of the measured traits in these populations. However, the evolvability of most traits did not vary consistently along the two gradients indicating that the evolutionary potential of peripheral populations was not reduced.
To conclude, this thesis has highlighted the importance of combining field surveys, population genetic studies, and ecological experiments to investigate plasticity and genetic variation in response to different environmental conditions. Gaining a deeper understanding of how plant populations adapt to changing environments is crucial for predicting their future responses to climate change. The results suggest that the abundant centre model (ACM) does not fully account for the observed population characteristics and genetic patterns in A. vulneraria. Other factors such as historical migration and local adaptation driven by varying selection pressures along the elevational and latitudinal gradients have also important effects in shaping the distribution of the species and its traits across different environments, and will shape its future responses to climate change. While the rather low phenotypic plasticity of the arctic and alpine populations of A. vulneraria alone may not be sufficient for them to persist, genetic variability in fitness-related traits together with gene flow may allow their adaptation to changing environmental conditions in the future.Die Verbreitung von Pflanzen und die Charakteristika ihrer Populationen werden stark von den Umweltbedingungen beeinflusst, denen sie ausgesetzt sind. Als Reaktion auf Umweltveränderungen können Populationen in neue Gebiete wandern, phänotypische Plastizität zeigen und sich evolutionär anpassen. Studien zum Vergleich von Populationsmerkmalen entlang von Höhen- und Breitengradienten bieten die Möglichkeit, den Einfluss verschiedener Umwelt- und historischer Faktoren auf die Merkmale von Pflanzenpopulationen zu bewerten. Zur Untersuchung der Plastizität und des evolutionären Potenzials einer Pflanze in Reaktion auf Umweltveränderungen habe ich einen integrativen Ansatz gewählt, der Feldstudien, populationsgenetische Studies und Experimente kombiniert. Die weit verbreitete Pflanze Anthyllis vulneraria wurde als Modellart ausgewählt, weil sie in Europa in verschiedenen Höhenlagen und über viele Breitengrade verbreitet ist. Insbesondere untersuchte ich entlang von Höhen- und Breitengradienten (1) die Merkmale der Lebensräume und Populationen von A. vulneraria, (2) die neutrale molekulargenetische Vielfalt und Differenzierung der Populationen, (3) die quantitative genetische Differenzierung und das evolutionäre Potenzial der Populationen. Der Höhengradient in den Alpen reichte von 500 m bis zur Höhengrenze auf 2500 m und der Breitengradient erstreckte sich über 2400 km von Mitteleuropa bis zur Verbreitungsgrenze im Norden. Die Länge der beiden Gradienten wurde so gewählt, dass sie einer ähnlichen Veränderung der Jahresmitteltemperatur von ca. 11,5 °C entsprach.
Ich untersuchte die Eigenschaften der Lebensräume von 40 Populationen von A. vulneraria entlang von Höhen- und Breitengradienten und untersuchte deren Einfluss auf die Eigenschaften der Populationen. Die Größe der Pflanzen und ihre Reproduktion nahmen entlang beider Gradienten ab, aber die Dichte der Pflanzen nahm zu, was auf eine höhere Rekrutierung und einen Ausgleich zwischen verschiedenen demographischen Prozessen hindeutet. Die Ergebnisse stützen die Ansicht, dass ein demographischer Ausgleich bei weit verbreiteten Arten häufig sein könnte. Es wurde festgestellt, dass Temperaturschwankungen die stärksten Auswirkungen auf verschiedene Populationsmerkmale entlang beider Gradienten haben, gefolgt von Unterschieden in Niederschlag, Sonneneinstrahlung und Bodennährstoffen. Der Anteil der blühenden Pflanzen, der Samenansatz und die Masse der Samen nahmen mit dem Breitengrad ab, was auf limitierende Ressourcen und reduzierte Bestäubung im Norden hindeutet, während die große Variation dieser Merkmale entlang des Höhengradienten nicht mit der Höhe oder damit korrelierten Umweltvariablen, sondern mit starken lokalen Unterschieden in den Umweltbedingungen in den alpinen Lebensräumen zusammenhing.
Ich untersuchte die molekulargenetische Vielfalt und Differenzierung der A. vulneraria Populationen anhand von Mikrosatelliten, die als neutrale Marker gelten, die von der natürlichen Selektion unbeeinflusst sind. Die genetische Vielfalt von Populationen nahm mit dem Breitengrad stark ab und die Differenzierung zwischen ihnen nahm zu. Diese Muster sind wahrscheinlich das Ergebnis von seriellen Gründereffekten während der Ausbreitung nach Norden infolge des Gletscherrückgangs nach der letzten Eiszeit. Die genetische Vielfalt und Differenzierung zwischen den Populationen von A. vulneraria hing nicht mit der Höhenlage zusammen. Diese Beobachtung könnte auf einen höheren Genfluss zurückzuführen sein, der durch den viel kürzeren Höhengradienten begünstigt wird. Ich fand jedoch Belege für eine Isolierung durch Entfernung entlang beider Gradienten, was auf einen eingeschränkten Genfluss zwischen den Populationen entlang beider Gradienten hindeutet. Die subarktischen Populationen unterschieden sich genetisch von den alpinen Populationen, was darauf hindeutet, dass die nördlichen Populationen nicht aus den hochgelegenen alpinen Populationen hervorgegangen sind.
Pflanzen, die aus Samen der untersuchten Populationen angezogen wurden, wurden in einem gemeinsamen Garten untersucht, um die quantitative genetische Differenzierung und phänotypische Plastizität dieser Populationen entlang von Höhen- und Breitengradienten zu bewerten und ihr evolutionäres Potenzial zu untersuchen. Die im Gemeinschaftsgarten gemessenen Merkmale wiesen eine klinale Variation mit der Höhe und dem Breitengrad des Herkunftsortes auf, was auf eine adaptive Differenzierung der Merkmale entlang der Gradienten hindeutet. Divergente Selektion wurde durch höhere QST-Werte (Messung der quantitativen genetischen Differenzierung) als FST-Werte (Messung der neutralen molekulargenetischen Differenzierung) bei einigen Merkmalen angezeigt. Außerdem stellte ich fest, dass die Unterschiede in der Größe zwischen Müttern und ihren Nachkommen bei Populationen aus höheren Lagen und Breitengraden geringer waren, was auf eine geringere Plastizität in diesen Populationen schließen lässt. Die quantitative genetische Variation der meisten Merkmale nahm jedoch nicht entlang der beiden Gradienten ab, was darauf hindeutet, dass das Evolutionspotenzial in peripheren Populationen nicht verringert ist.
Zusammenfassend hat diese Arbeit deutlich gemacht, wie wichtig es ist, Felderhebungen, populationsgenetische Untersuchungen und ökologische Experimente zu kombinieren, um die Plastizität und genetische Variation als Reaktion von Arten auf unterschiedliche Umweltbedingungen zu untersuchen. Ein tieferes Verständnis dafür, wie sich Pflanzenpopulationen an veränderte Umweltbedingungen anpassen, ist entscheidend für die Vorhersage ihrer künftigen Reaktion auf den Klimawandel. Die Ergebnisse deuten darauf hin, dass das „abundant centre model“ (ACM) die beobachteten Unterschiede in den Merkmalen der Populationen und die genetischen Muster bei A. vulneraria nicht vollständig erklären kann. Andere Faktoren wie historische Migration und lokale Anpassung, die durch einen unterschiedlichen Selektionsdruck entlang der Höhen- und Breitengradienten angetrieben werden, könnten eine bedeutendere Rolle bei der Verbreitung der Art und der Ausbildung der Merkmale der Art in verschiedenen Umwelten gespielt haben und ihre künftigen Reaktionen auf den Klimawandel beeinflussen. Während die geringere phänotypische Plastizität der arktischen und alpinen Populationen von A. vulneraria möglicherweise nicht ausreicht für ihr Überleben, könnte ihre genetische Variabilität in fitnessrelevanten Merkmalen ihre Anpassung an sich veränderte Umweltbedingungen ermöglichen
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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