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Aspectos metabólicos del comportamiento depredador de hembras y machos de la araña Phoneutria boliviensis
No full textLas arañas (Aranae) se ubican en la séptima posición, como el grupo de organismos más diverso en el planeta, además son un orden principalmente de depredadores terrestres . De este modo tienen gran importancia en los ecosistemas donde se encuentran ya que establecen regulación poblacional de otros artrópodos teniendo un efecto de equilibrio ecológico. Phoneutria boliviensis es considerada una de las especies de arañas de mayor importancia médica en Colombia , esto se ve reflejado en los estudios realizados acerca de biología y toxicología de esta especie, es por esto que en este trabajo se propone estudiar la tasa metabólica estándar y durante la depredación en P. boliviensis. Para lograr este objetivo se utilizaron las presas preferidas encontradas en un trabajo realizado anteriormente por Valenzuela-Rojas . Las presas seleccionadas para el experimento fueron: Hemidactylus frenatus (vertebrado) y Spinoctenus sp. (invertebrado). Para determinar la posible diferencia en costos energéticos en el momento de depredación sobre presas de diferente tipo, se realizaron mediciones de metabolismo en tiempo real con el fin de estimar la TME (Tasa Metabólica Estándar) y la tasa metabólica durante la depredación. Los datos fueron analizados mediante un ANCOVA utilizando la herramienta digital InfoStat. Se encontró que la tasa metabólica entre machos y hembras de Phoneutria boliviensis no posee diferencias significativas que permita caracterizar un hábito particular de caza dependiente del sexo. Se evidenció en cuanto a la tasa metabólica de depredación un aumento considerable entre las etapas de reposo y activación de los especímenes evaluados. También se encontró que el tamaño de la presa afecta el gasto energético que P. boliviensis emplea para el sometimiento mediante la mordida.
Los resultados sugieren que el metabolismo estándar de P. boliviensis poseen valores bajos con respecto a otros artrópodos, la TME no difiere entre sexos, sin embargo P. boliviensis mostró diferencia en el metabolismo durante el comportamiento depredador sobre diferentes presas, en donde los machos presentaron mayor metabolismo cuando depredaron sobre Hemidactylus frenatus
Comportamiento depredador en machos y hembras de Phoneutria boliviensis (F. O. PICKARD CAMBRIDGE, 1897), bajo condiciones de laboratorio
No full textPhoneutria es uno de los géneros de arañas más peligrosos del mundo y su distribución va desde la selva de Costa Rica hacia el norte de Argentina, donde son responsables de accidentes humanos dado su comportamiento agresivo defensivo y la toxicidad del veneno. Diferentes estudios han analizado las toxinas del veneno de estas arañas pero aspectos como su biología y comportamiento han sido poco explorados. En las arañas, el comportamiento depredador se encuentra estrechamente ligado a la toxicidad, teniendo en cuenta que el veneno junto con la seda, son principalmente los mecanismos empleados al capturar presas. Se ha demostrado que la presencia de ciertas toxinas especificas en algunas arañas del genero Latrodectus obedecen a la captura de vertebrados. Sin embargo, pocos trabajos han abordado la toxicidad en las arañas en función de la dieta, desconociéndose la acción del veneno en presas naturales. El presente trabajo tuvo como objetivo analizar el comportamiento depredador de Phoneutria boliviensis. La araña con más amplia distribución del género en Colombia. Considerando que la toxicidad y el comportamiento depredador puede variar según el sexo. Se emplearon 20 machos y 20 hembras a los que se les suministraron distintos tipos de presa (invertebrados/vertebrados) de manera aleatoria. Se compararon tasa de aceptación, tiempos de inmovilización y comportamiento de captura entre los sexos y a nivel de distintas presas. Encontramos que P. boliviensis es una araña generalista que consume tanto invertebrados como vertebrados en condiciones de laboratorio. Además, su comportamiento depredador parece ser no estereotipado y diferente entre sexos.Phoneutria genus is among of the most dangerous spider in the world and its distribution from the Costa Rican jungle to northern Argentina, where those responsible for human accidents are its aggressive behavior and poison toxicity. Different studies have analyzed poison toxins from these areas. In spiders, predator behavior is closely linked to toxicity, taking into account that poison along with silk are mainly the mechanisms used to capture prey. Recently it was shown that the presence of certain specific toxins in some spiders of the genus Latrodectus obey to the capture of prey as vertebrates. However, few works have addressed spider toxicity in diet function, ignoring the action of venom in natural prey. The present work aimed to analyze the predatory behavior of Phoneutria boliviensis. The great distribution of the genus in Colombia. Considering that, the toxicity can vary according to sex. 20 males and 20 females will be used to which different types of prey (invertebrates / vertebrates) will be supplied randomly. Acceptance prey, immobilization times and capture behavior between the sexes and the level of the different dams were compared. We found that P. boliviensis is a generalist spider that consumes both invertebrates and vertebrates in laboratory conditions. In addition, their predatory behavior seems not to be stereotyped and different between sexes
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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