1,720,960 research outputs found
Mariposas de alta montaña. un caso de estudio en el Macizo de Bijagual, Boyacá
No full textSpa: El departamento de Boyacá es una de las regiones geográficas de Colombia con mayores vacíos de información sobre la diversidad de mariposas diurnas y en especial la alta montaña debido a varios factores como la ausencia de inventarios sistematizados y la extrapolación de información con otras regiones del país. Con lo expuesto se intenta conocer y describir las comunidades de mariposas con criterios de diversidad, presentes en 3 coberturas vegetales en el macizo de Bijagual en Boyacá. En estas áreas del macizo, las coberturas fueron bosque secundario temprano (8-12 años), tardío (16-20 años) y un rastrojal de aproximadamente de 10 años; estas se encuentran en una franja altitudinal de 2800 a 3100 msnm. Los muestreos se realizaron en dos épocas climáticas durante el segundo semestre del 2011 y parte del primero del 2012 (septiembre/octubre - húmeda- y diciembre/enero -seca-). Se colectaron 1465 ejemplares de mariposas distribuidas en cuatro familias, 8 subfamilias, 33 especies y 11 subespecies para un total de 44 taxones a nivel específico y subespecífico de mariposas. De otra parte las curvas de acumulación de especies por cobertura vegetal presentan una alta representatividad del esfuerzo de muestreo según la estimadores de riqueza utilizados (Chao1, Jack1, ACE).Como respuesta al régimen climático se observaron cambios significativos en las abundancias, la diversidad y la dominancia mientras que la riqueza se mantuvo relativamente constante. La única cobertura que mostró diferencias en el ensamblaje fue el rastrojal. Palabras clave: Andes, diversidad, mariposas, alta montaña
A new species of Scybalocanthon Martínez 1948 (Coleoptera: Scarabaeinae) of the colombian Andes
No full textSe describe una nueva especie del género Scybalocanthon (Martínez 1948), Scybalocanthon magnus sp. nov., de los bosques de alta montaña en los Andes orientales de Colombia. La morfología externa, así como el órgano genital masculino y femenino de especímenes adultos son ilustrados y comparados con la especie cercanamente relacionada: Scybalocanthon arcabuquensis Molano & Medina 2010.A new species of the genus Scybalocanthon Martínez 1948, Scybalocanthon magnus sp. nov. is described from high elevation forest in the Eastern Andes of Colombia. The external morphology as well as male and female genitalia of adult specimens are illustrated and compared with the most closely related species: Scybalocanthon arcabuquensis Molano & Medina 2010
A new species of Scybalocanthon Martínez 1948 (Coleoptera: Scarabaeinae) of the colombian Andes
Full text linkSe describe una nueva especie del género Scybalocanthon (Martínez 1948), Scybalocanthon magnus sp. nov., de los bosques de alta montaña en los Andes orientales de Colombia. La morfología externa, así como el órgano genital masculino y femenino de especímenes adultos son ilustrados y comparados con la especie cercanamente relacionada: Scybalocanthon arcabuquensis Molano & Medina 2010.A new species of the genus Scybalocanthon Martínez 1948, Scybalocanthon magnus sp. nov. is described from high elevation forest in the Eastern Andes of Colombia. The external morphology as well as male and female genitalia of adult specimens are illustrated and compared with the most closely related species: Scybalocanthon arcabuquensis Molano & Medina 2010
Mariposas-polilla gigantes (Lepidoptera: Castniidae: Castniinae) en la Colección Entomológica del Instituto de Investigación de Recursos Biológicos Alexander von Humboldt
No full textA revision of the giant butterfly-moths (Castniidae: Castniinae) of deposited specimens in the entomological collection of the Alexander von Humboldt Institute was made. 13 specimens belonging to 7 species within 4 genera were found. General comments of the biology and presence in Colombia of the specimens are presented. Also, a brief history of the entomological collection of the Alexander von Humboldt Institute is included.Se realizó la revisión de los ejemplares de mariposa-polilla gigantes (Castniidae: Castniinae) depositados enla colección entomológica del Instituto de Investigación de Recursos Biológicos Alexander von Humboldt,Colombia. Se encontraron 13 ejemplares pertenecientes a 7 especies en 4 géneros. Se presentan comentariosgenerales acerca de la biología y presencia en Colombia de los ejemplares examinados. Se incluye una brevehistoria de la colección entomológica del Instituto Alexander von Humboldt
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
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