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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
Non hai volta atrás: cambios nas interaccións bióticas promovidas por plantas exóticas invasoras
No full textPlant invasions are one of the main direct drivers of species loss in nature, seriously altering the habitat structure and leading to substantial effects on ecosystem functioning. Globalization, habitat fragmentation, and climate change facilitates the migration and colonization of these exotic species, that induce changes on native communities through disruption of biotic interactions. These changes are currently taking place at rates unprecedented in the period newly defined as the Anthropocene. Many questions related to plant invasions have been answered in the last decades. However, directions of most recent studies tend to be very global or only focus in a particular assemblage of species, with few considering the many functional and trophic roles of entire groups. It is widely known that environmental disturbances clearly facilitate the spread of invasive plants. Nevertheless, the changes in the plant-herbivore interactions and the alteration of the invertebrate species composition have received little attention, as well as which environmental factors may favour the invasion success of unaltered ecosystems. To carry out this doctoral dissertation, a greenhouse experiment and several fieldwork studies were developed on vulnerable native ecosystems in the northwestern Iberian Peninsula. This region presents some of the most problematic plant species worldwide: three invasive woody Acacia spp. (Acacia dealbata Link, Acacia longifolia (Andr.) Willd. and Acacia melanoxylon R. Br.) and the invasive Carpobrotus edulis (L.) N.E. Br. The main objective of this doctoral dissertation is to elucidate whether the impact generated by the plant invasions on the native plant communities alter the biotic interactions, especially affecting the plant-herbivore interactions, and changing the invertebrate species composition due to the presence of these invasive plants. The results showed that A. dealbata can emerge and growth in unaltered plant communities, favouring their expansion under natural conditions and adjusting the growth to the ecosystem characteristics. Besides, the microhabitat conditions of areas invaded by A. dealbata play an important role for the establishment of native species, even being the main factor affecting seedling establishment rather than changes in soil properties or allelopathy. Moreover, the results obtained indicate that A. dealbata and C. edulis can accumulate new natural enemies in the introduced range, but damages found did not seem enough to exert an effective natural control. Carpobrotus edulis may also alter the associated herbivore community structure by changing the plant-herbivore interactions and influencing the occurrence of herbivore assemblages. Finally, it is noted that the invasive plants studied alter the biodiversity and ecosystem functioning by reducing the invertebrate assemblages and functional diversity. Overall, the results presented here provide evidence that invasive plants alter the biotic interactions, especially affecting the plant-herbivore interactions and changing the invertebrate species composition. It is important to explore the direct and indirect effects produced by plant invasions on the taxonomic and functional diversity to detect alterations of the associated organisms at ecosystem scale. Predicting such changes poses a serious challenge to conserve the ecosystems in a time of rapid environmental disturbance. This information is vital to define long-term management strategies for reducing the spread of these invasive plants.Las invasiones de plantas son uno de los principales impulsores de la pérdida de especies en la naturaleza, alterando seriamente la estructura del hábitat y produciendo efectos negativos en el funcionamiento de los ecosistemas. La globalización, la fragmentación del hábitat y el cambio climático facilitan la migración y la colonización de estas especies exóticas, que inducen cambios en las comunidades nativas a través de la interrupción de las interacciones bióticas. Estos cambios están ocurriendo actualmente a tasas sin precedentes en el período recientemente definido como el Antropoceno. Muchas preguntas relacionadas con las invasiones de plantas han sido respondidas en las últimas décadas. Sin embargo, las direcciones de los estudios más recientes tienden a ser muy globales o solo se centran en un conjunto particular de especies, y pocos consideran los muchos roles funcionales y tróficos de grupos enteros. Es ampliamente conocido que las perturbaciones ambientales facilitan claramente la propagación de plantas invasoras. Sin embargo, los cambios en las interacciones planta-herbívoro y la alteración de la composición de especies de invertebrados han recibido poca atención, así como qué factores ambientales pueden favorecer el éxito de la invasión de ecosistemas inalterados. Para llevar a cabo esta tesis doctoral, se desarrolló un experimento de invernadero y varios estudios de campo en ecosistemas nativos vulnerables en el noroeste de la península ibérica. Esta región presenta algunas de las especies de plantas más problemáticas a nivel mundial: tres Acacia spp leñosas invasoras. (Acacia dealbata Link, Acacia longifolia (Andr.) Willd. y Acacia melanoxylon R. Br.) y la invasora Carpobrotus edulis (L.) N.E. Br. El objetivo principal de esta tesis es dilucidar si el impacto generado por las invasiones de plantas en las comunidades de plantas nativas altera las interacciones bióticas, especialmente afectando las interacciones planta-herbívoro, y cambiando la composición de especies de invertebrados debido a la presencia de estas plantas invasoras. Los resultados mostraron que A. dealbata puede emerger y crecer en comunidades de plantas inalteradas, favoreciendo su expansión en condiciones naturales y ajustando el crecimiento a las características del ecosistema. Además, las condiciones de microhábitat de las áreas invadidas por A. dealbata juegan un papel importante para el establecimiento de especies nativas, incluso siendo el factor principal que afecta el establecimiento de las plántulas en lugar de los cambios en las propiedades del suelo o la alelopatía. Además, los resultados obtenidos indican que A. dealbata y C. edulis pueden acumular nuevos enemigos naturales en el rango introducido, pero los daños encontrados no parecen ser suficientes para ejercer un control natural efectivo. Carpobrotus edulis también puede alterar la estructura de la comunidad de herbívoros asociada al cambiar las interacciones planta-herbívoro e influir en la aparición de grupos de herbívoros. Finalmente, se observa que las plantas invasoras estudiadas alteran la biodiversidad y el funcionamiento del ecosistema al reducir los grupos de invertebrados y la diversidad funcional. En general, los resultados presentados aquí proporcionan evidencia de que las plantas invasoras alteran las interacciones bióticas, especialmente afectando las interacciones planta-herbívoro y cambiando la composición de las especies de invertebrados. Es importante explorar los efectos directos e indirectos producidos por las invasiones de plantas en la diversidad taxonómica y funcional para detectar alteraciones de los organismos asociados a escala de ecosistema. Predecir tales cambios plantea un serio desafío para conservar los ecosistemas en un momento de perturbación ambiental rápida. Esta información es vital para definir estrategias de manejo a largo plazo para reducir la propagación de estas plantas invasoras.As invasións de plantas son un dos principais motores da perda de especies na natureza, alterando seriamente a estrutura do hábitat e producindo efectos negativos no funcionamento dos ecosistemas. A globalización, a fragmentación do hábitat e o cambio climático facilitan a migración e colonización destas especies exóticas, o que induce cambios nas comunidades nativas mediante a interrupción das interaccións bióticas. Estes cambios están producíndose actualmente a taxas sen precedentes no período definido recentemente como o Antropoceno. Nas últimas décadas respondéronse moitas preguntas relacionadas coas invasións de plantas. Non obstante, as direccións dos estudos máis recentes adoitan ser moi globais ou só se centran nun determinado conxunto de especies, e poucos consideran os moitos roles funcionais e tróficos de grupos enteiros. É moi coñecido que as perturbacións ambientais facilitan claramente a propagación de plantas invasoras. Non obstante, os cambios nas interaccións planta-herbívoro e a alteración da composición de especies invertebradas recibiron pouca atención, así como o que os factores ambientais poden favorecer o éxito da invasión de ecosistemas non alterados. Para realizar esta tese doutoral, elaborouse un experimento de invernadoiro e varios estudos de campo en ecosistemas nativos vulnerables do noroeste da Península Ibérica. Esta rexión presenta algunhas das especies vexetais máis problemáticas a nivel mundial: tres leñosas invasivas Acacia spp. (Acacia dealbata Link, Acacia longifolia (Andr.) Willd. e Acacia melanoxylon R. Br.) e a invasora Carpobrotus edulis (L.) N.E. Br. O obxectivo principal desta tese é dilucidar se o impacto xerado polas invasións de plantas en comunidades vexetais nativas altera interaccións bióticas, especialmente afectando as interaccións planta-herbívoro e cambiar a composición de especies invertebradas debido á presenza destas plantas invasoras. Os resultados demostraron que A. dealbata pode xurdir e crecer en comunidades de plantas non alteradas, favorecendo a súa expansión en condicións naturais e axustando o crecemento ás características do ecosistema. Ademais, as condicións de microhabitat das zonas invadidas por A. dealbata xogan un papel importante no establecemento de especies autóctonas, incluso sendo o principal factor que afecta o establecemento de mudas máis que os cambios nas propiedades do solo ou a alelopatía. Ademais, os resultados obtidos indican que A. dealbata e C. edulis poden acumular novos inimigos naturais no rango introducido, pero os danos atopados non parecen ser suficientes para exercer un control natural eficaz. O Carpobrotus edulis tamén pode alterar a estrutura da comunidade herbívora asociada ao cambio das interaccións planta-herbívoros e influír na aparición de conxuntos herbívoros. Finalmente, obsérvase que as plantas invasoras estudadas alteran a biodiversidade e o funcionamento do ecosistema reducindo os conxuntos de invertebrados e a diversidade funcional. En xeral, os resultados aquí presentados evidencian que as plantas invasoras alteran as interaccións bióticas, afectando especialmente ás interaccións planta-herbívoro e cambiando a composición de especies de invertebrados. É importante explorar os efectos directos e indirectos producidos polas invasións de plantas en diversidade taxonómica e funcional para detectar alteracións dos organismos asociados a escala do ecosistema. Prever estes cambios supón un desafío para conservar os ecosistemas nun momento de rápida perturbación ambiental. Esta información é vital para definir estratexias de xestión a longo prazo para reducir a propagación destas plantas invasoras.Xunta de Galicia FEDER|Ref. GRC2015/012Xunta de Galicia|Ref. ED431E 2018/07Ministerio de Economía y Competitividad|Ref.CGL2013- 48885-C2-1-
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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