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    Taxonomía de Holothuroidea (Echinodermata) del mar del Perú

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    Al Consejo Nacional de Ciencia y Tecnología (CONCYTEC), por su apoyo económico para mi estadía en México, y al Consejo Superior de Investigaciones (CSI), de la Universidad Nacional Mayor de San Marcos por el apoyo económico brindado.Se presentan 22 especies de holoturoideos habitantes del mar del Perú, distribuidas sistemáticamente en tres órdenes, ocho familias y trece géneros. Se incluye el catálogo para cada especie: morfología externa, microscopía electrónica de barrido (MEB) de los osículos y mapa de distribución; así como información sobre la distribución batimétrica y localidad tipo, entre otros aspectos; además una clave de identificación taxonómica para las especies del mar del Perú.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte

    Taxonomía de Holothuroidea (Echinodermata) del mar del Perú

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    Se presentan 22 especies de holoturoideos habitantes del mar del Perú, distribuidas sistemáticamente en tres órdenes, ocho familias y trece géneros. Se incluye el catálogo para cada especie: morfología externa, microscopía electrónica de barrido (MEB) de los osículos y mapa de distribución; así como información sobre la distribución batimétrica y localidad tipo, entre otros aspectos; además una clave de identificación taxonómica para las especies del mar del Perú. Los ámbitos de distribución batimétrica varían de 0 a 1,412 m. Se aportan ocho nuevos registros para el mar del Perú: Pentamera chierchia, Neocucumis veleronis, Holothuria (Cystipus) inhabilis, Holothuria (Selenkothuria) lubrica, Holothuria (Semperothuria) imitans, Holothuria (Vaneyothuria) zacae, Molpadia intermedia y Caudina californica. Se amplía el ámbito de distribución geográfica, a su límite más sureño, de las siguientes especies: Neocucumis veleronis, Holothuria (Cystipus) inhabilis, Holothuria (Selenkothuria) lubrica, Holothuria (Semperothuria) imitans, Holothuria (Vaneyothuria) zacae, Molpadia intermedia y Caudina californica. Se amplía el ámbito de distribución batimétrica de las siguientes especies: Pentamera chiloensis, Holothuria (Selenkothuria) lubrica y Holothuria (Vaneyothuria) zacae. Las especies de pepinos de mar más características del Perú son: Pattalus mollis y Athyonidium chilensis. Palabras clave: Taxonomía, Echinodermata, Holothuroidea, pepinos de mar, Perú, nuevos registros.--- Twenty-two species of sea cucumbers inhabiting Peruvian waters are reported. They are included in three orders eight families and thirteen genera. Each species is illustrated in a catalogue: information about external morphology, electronic scanning microscopy of the spicules and distribution maps is included; also information about bathymetric distribution and type locality of each species, as well as a taxonomic key for the Peruvian species are also presented. Bathymetric ranges vary between 0 and 1412 m. Eight new records for Peru are remarkable: Pentamera chierchia, Neocucumis veleronis, Holothuria (Cystipus) inhabilis, Holothuria (Selenkothuria) lubrica, Holothuria (Semperothuria) imitans, Holothuria (Vaneyothuria) zacae, Molpadia intermedia and Caudina califórnica. The geographic range of Neocucumis veleronis, Holothuria (Cystipus) inhabilis, Holothuria (Selenkothuria) lubrica, Holothuria (Semperothuria) imitans, Holothuria (Vaneyothuria) zacae, Molpadia intermedia y Caudina califórnica is widened to southward. The bathymetric range of Pentamera chiloensis, Holothuria (Selenkothuria) lubrica and Holothuria (Vaneyothuria) zacae is widened. The sea cucumbers more characteristic of Peruvian sear are Pattalus mollis and Athyonidium chilensis. Keywords: Taxonomy, Echinodermata, Holothuroidea, sea cucumber, Peru, new records.Tesi

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The 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

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    “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

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    We 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

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    We 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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