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El conocimiento florístico de la Península de Yucatán, México, actualización y colecciones botánicas
No full textLa Península de Yucatán como provincia biogeográfica está conformada de los estados mexicanos de Campeche, Quintana Roo, Yucatán y de las regiones septentrionales de Belice y Guatemala. Esta provincia posee una geología cárstica, hidrografía superficial escasa, elevaciones menores de 350 metros y un gradiente de precipitación que permite la formación de diferentes asociaciones vegetales, siendo las selvas caducifolias, subcaducifolias y perennifolias las más predominantes. La información florística de esta región se actualiza constantemente y en el presente trabajo, se incluye una actualización para la flora endémica vascular partiendo del último listado de la PBPY mexicana (Carnevali et al., 2010). Se ha propuesto la aplicación de un índice de densidad de colección botánica (IDCB, número de colecciones botánicas/área km2), como herramienta para evaluar el estado de conocimiento florístico. Por ejemplo, una estimación previa muestra un índice de 159 muestras/km2 para el estado de Yucatán, pero debido a un intenso esfuerzo de recolecta botánica en últimos 20 años posiblemente éste estado cuente con un índice cercano a 200 muestras/km2. Además se incluyen cambios en el listado de especies endémicas de la Provincia Biótica Península de Yucatán a partir de una revisión bibliográfica y se calculó el IDCB a nivel de municipio para Campeche y Quintana Roo. En estos estados se requieren intensas colecciones botánicas generales en especial fuera del área de influencia de carreteras y centros poblados
LA FAMILIA ICACINACEAE MIERS EN VENEZUELA
No full textRESUMENSe presenta el tratamiento de la familia Icacinaceae para la flora de Venezuela. La familia incluye nueve géneros y 21 especies en el país. El género más diverso es Emmotum con siete especies, todas restringidas a la Guayana. Se proporciona una clave para la identifica- ción de los taxones, descripciones morfológicas, notas taxonómicas e información sobre la distribución geográfica, así como ilustraciones de algunas de ellas. Tres especies pueden ser consideradas como endemismos locales: Emmotum celiae, E. fulvum y E. yapacanum.ABSTRACTA treatment of the family Icacinaceae for the flora of Venezuela is presented. The family includes nine genera and 21 species for the country. Emmotum is the most diverse genus with seven species restricted to the Guayana. Keys for taxon identification, morpho- logical description, taxonomic notes, and information about the geographic distribution are provided, as well as some illustrations for some Venezuelan species. Three species can be considered as local endemic: Emmotum celiae, E. fulvum y E. yapacanum
Dos especies nuevas del g\ue9nero Drosera (Droseraceae) in Venezuela y otros comentarios taxon\uf3micos
No full textVolume: 5Start Page: 241End Page: 24
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
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
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