1,720,957 research outputs found
A new species of Chiasmocleis Méhely, 1904 (Anura: Microhylidae) from the Peruvian Amazonia
No full textRojas-Padilla, Omar, Gagliardi-Urrutia, Giussepe, Rios-Alva, Ehiko J., Castroviejo-Fisher, Santiago (2022): A new species of Chiasmocleis Méhely, 1904 (Anura: Microhylidae) from the Peruvian Amazonia. Zootaxa 5195 (1): 24-50, DOI: https://doi.org/10.11646/zootaxa.5195.1.
Caracterización morfométrica y molecular de especies de anfibios y reptiles de la Estación Biológica José Álvarez Alonso, Loreto – Perú
Get PDFDuring the months of September and October 2021, we conducted sampling within the José Álvarez Alonso Biological Station using the technique of visual encounter surveys and molecular analysis in the installations of the Laboratory of Biology and Molecular Genetics, both belonging to the Peruvian Amazon Research Institute (Instituto de Investigaciones de la Amazonía Peruana). The main objective of this research was to characterize morphometrically and molecularly amphibian and reptile species of the EBJAA. We reported 153 individuals divided into 61 species between amphibians and reptiles, from which nucleotide sequences of the Cytochrome Oxidase - I gene were obtained from 81 individuals divided into 46 species. All individuals were measured at least with the snout-vent length, which helped us to determine which species would be used in the morphometric analysis. Preliminary Principal Component Analysis (PCA) only allowed us to perform morphometric characterization in three amphibian genera since the number of individuals per reptile species was not significant for statistical analysis. The analyses showed that snout-ventral length, head width and tibia length measurements could be used as morphometric characters for genus discrimination. Sequences of 20 species were added to the Genbank and the use of the combination of morphometric and molecular tools allowed us to correct the identification of the species Pristimantis brevicruz, Boana fasciata and B. tetete, which were misidentified. We conclude that the morphometric measurements used helped to find differential diagnostic characters, however, only using these characters does not ensure an adequate identification, so combining it with molecular analysis is necessary to obtain true and reliable data.Durante los meses de setiembre y octubre del 2021 se realizaron muestreos dentro de la Estación Biológica José Álvarez Alonso utilizando la técnica de relevamientos por encuentro visuales y análisis moleculares en las instalaciones del Laboratorio de Biología y Genética Molecular ambas pertenecientes al Instituto de Investigaciones de la Amazonía Peruana. El objetivo principal de esta investigación fue caracterizar morfométrica y molecularmente a especies de anfibios y reptiles de la EBJAA. Reportamos un total de 153 individuos divididos en 61 especies entre anfibios y reptiles, de los cuales se obtuvieron secuencias nucleotídicas del gen Citocromo Oxidasa - I de 81 individuos divididos en 46 especies entre anfibios y reptiles. Todos los individuos fueron medidos al menos con la longitud hocico cloaca la cual nos ayudó a determinar que especies se utilizarían en los análisis morfométricos. El análisis preliminar de componentes Principales (PCA por sus siglas en inglés) solo nos permitió realizar la caracterización morfométrica en tres géneros de anfibios ya que el número de individuos por especies de reptiles no fue significativo para realizar análisis estadísticos, con los análisis mostramos que las medidas longitud hocico-cloaca, ancho de cabeza y longitud de tibia pueden utilizarse como carácter morfométrico para la discriminación de géneros. Se incrementaron secuencias de 20 especies al Genbank y el uso de la combinación de las herramientas morfométricas y moleculares nos permitió corregir a la identificación de la especie Pristimantis brevicruz, Boana fasciata y B. tetete las cuales fueron identificadas de manera errónea. Concluimos que Las medidas morfométricas utilizadas ayudaron a encontrar caracteres diagnósticos diferenciales, sin embargo, solo utilizar estos caracteres no asegura una adecuada identificación por lo que combinarlo con análisis moleculares es necesario para obtener datos verídicos y confiables
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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