1,720,964 research outputs found
Reproduction and minimal sizes for commercial sponges catches: aims for incrementing Cuban’s sponges culture.
No full textEl desconocimiento de los procesos reproductivos y la talla de madurez sexual de las esponjas comerciales de baño (familia Spongiidae) en Cuba constituye, actualmente, una limitante para el adecuado manejo de la pesquería de estas especies. El objetivo de esta revisión fue compilar la información existente sobre reproducción de esponjas comerciales, experiencias de repoblación basados en sistemas de cultivo, y el establecimiento de tallas mínimas de captura. La información acumulada posibilitó identificar vacíos en el conocimiento regional, inferir tallas límite para regular la actividad extractiva en Cuba y elaborar una propuesta de medidas coyunturales que minimicen el riesgo del colapso en la pesquería cubana de esponjas. Se comprobó que urge la realización de estudios histológicos, citológicos y de supervivencia larval en las especies cubanas. Además, se corroboró que una talla mínima legal de 15 cm de diámetro mayor se corresponde con los estándares internacionales actualmente establecidos para esponjas comerciales de otras regiones y, por tanto, contribuiría a mejorar el rendimiento pesquero sin mayores afectaciones al potencial reproductivo de las poblaciones en explotación. Sin embargo, la extracción de esponjas menores (a 15 cm de diámetro mayor) podría hacer colapsar la población por generar fallas en el reclutamiento y afectaciones desconocidas en los procesos reproductivos poblacionales. La implementación definitiva del cultivo de esponjas a escala nacional es la solución más plausible y biológicamente aceptable para la obtención de las esponjas de pequeña talla, que satisfacen de mejor manera las actuales demandas del mercado internacional.The lack of knowledge about the reproductive processes and the size of sexual maturity of commercial bath sponges (Family Spongiidae) in Cuba, currently constitutes a limitation to develop adequate management and conservation plans in the fishery of these species. This review aimed to summarize the existing information on the reproduction of commercial sponges, repopulation experiences based on farming systems, and the establishment of minimum capture sizes. These data helped to identify the main gaps in regional knowledge, to infer size limit to regulate extractive activity in Cuba, and to prepare conjunctural measures that minimize the risk of collapse in the Cuban sponge’s fishery. It was concluded that it is urgent the need of histological, cytological, and larval survival studies in Cuban species. In addition, it was confirmed that a legal minimum size of 15 cm in largest diameter corresponds to the international standards currently established for commercial sponges from other regions and, therefore, would contribute to improving fishing yield without further affecting the reproductive potential of populations in exploitation. However, the extraction of smaller individuals (with a largest diameter of 15 cm or smaller) could cause the population to collapse due to recruitment failures and unknown effects on population reproductive processes. The definitive implementation of sponge culture on a national scale is the most plausible and biologically acceptable solution for obtaining small-sized sponges, which better satisfy the current demands of the international market.PublishedReferee
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
Tasa de depredación de Panulirus argus (Decapoda: Palinuridae) sobre moluscos gastrópodos en dos zonas pesqueras al sur de Cuba
Full text linkLa langosta espinosa Panulirus argus es un mesodepredador que tiene un impacto en las poblaciones de moluscos bentónicos que constituyen su alimento. En el presente estudio, se determinó la composición de la dieta de P. argus y la presión de depredación que ejerce sobre los gastrópodos de las regiones pesqueras Santa Cruz del Sur (SCrso) y golfo de Batabanó (GB), Cuba. Mediante arrastres se cuantificó la densidad y diversidad de gastrópodos, que, basado en la abundancia de langostas, sirvió para estimar el impacto de la depredación. Se capturaron 250 langostas: 62 en SCrso octubre 2012, 136 en el GB febrero 2014 y 52 en el GB julio 2018. La vacuidad fue similar en SCrso (38,7%) y en el GB (38,0%). Se registraron 13 categorías tróficas, las más frecuentes: opérculos (48,8%) y restos de crustáceos (48,0%), de conchas (47,2%) y vegetales (35,0%), demostrando que la dieta se compone principalmente de moluscos y crustáceos. La frecuencia de ocurrencia de vegetales sugiere consumo no accidental. Se identificaron 17 especies de moluscos, siendo Tegula fasciata, Phrontis antillarum, Aliger gigas, Turbo castanea y Chione cancellata las más frecuentes. La mayor tasa de depredación fue sobre las especies T. fasciata (3,36), P. antillarum (0,54) y A. gigas (0,45). La presión de depredación fue 0,92 gastrópodos langosta-1 en SCrso y 3,31 gastrópodos langosta-1 en el GB, lo que según las respectivas densidades de langostas (3.546 langostas km-2 y 3.837 langostas km-2) y gastrópodos (3,76 ind. m-2 y 1,45 ind. m-2), demostró que P. argus consume 0,087% de los gastrópodos en SCrso y 0,887% en el GB. Se encontraron además evidencias de canibalismo
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
El inglés en las revistas de impacto ¿un alentador intento de unificar o una excusa para marginar?
Full text linkActually, there is a current trend to unify criteria of form making understandable and comparable the scientific results at an international level. Nevertheless, it is true that the desire to impose a single language on scientific publications could constitute a limiting dogma. This manuscript aimed to present criteria favoring all researchers who do not produce science in English language. The lists of journals indexed in the Journal Citation Report 2022, which include 12,828 scientific journals, 6,691 social science journals, 3,092 arts and humanities journals, and 5,300 open access journals, were analyzed. It was found that less than 1% of the reviewed lists correspond to journals that publish works in Spanish. Although the importance of English for the development, teaching and dissemination of science is generally recognized, most of the consulted bibliography exposes the dictatorial nature of English in science, where 95% of the articles are published in that language, and only less than 1% in Spanish or Portuguese. Specifically on marine biology, which constituted the aim of this text, the number of "high impact" scientific journals that accept papers in Spanish, or any other language that is not English, is fewer than ever. Publishing only in English implicitly grants the right of universalization to only one language, which could be wrong.Aunque es cierto que no está desacertada la tendencia de unificar criterios de forma con vistas a hacer comprensibles y comparables los resultados científicos a nivel internacional, es también cierto que constituye un dogma limitante el deseo de imponer un solo idioma a las publicaciones científicas. El objetivo de este texto es exponer criterios en favor de todos aquellos investigadores que no producen ciencia en idioma inglés. Se analizaron las listas de revistas indexadas en el Journal Citation Report 2022, que incluyen 12.828 revistas científicas, 6.691 revistas de ciencias sociales, 3.092 revistas de arte y humanidades, y 5.300 revistas de acceso abierto. Se encontró que menos del 1% de las listas revisadas corresponde a revistas que publican trabajos en lengua española. Aunque de manera general se reconoce la importancia del inglés para el desarrollo, la enseñanza y la difusión de la ciencia, la mayoría de la bibliografía consultada expone el carácter dictatorial del inglés en la ciencia, donde el 95% de los artículos se publica en esa lengua y solo menos del 1% en español o portugués. Específicamente en la temática de la biología marina, que constituyó el objeto fundamental de este texto, cada vez son menos las revistas científicas “de alto impacto” que aceptan trabajos en idioma español, o cualquier otro idioma que no sea inglés. Publicar sólo en inglés implícitamente le confiere el derecho de la universalización sólo a un idioma, lo cual puede ser errado
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
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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