1,721,043 research outputs found
Gyrodactylus poeciliae Harris & Cable 2000
No full textGyrodactylus poeciliae Harris & Cable, 2000 (Figure 21; Tables 4 and 7) Type host: Poecilia caucana Steindachner (“Cauca molly”, “piponcita”). Site of infection: Body surface. Type locality: La Concepción, Venezuela. Type material examined: Holotype (BMNH 1999.4.12.1). Comments: The marginal hook sickles of G. poeciliae are arguably most similar to those of G. costaricensis in having a large, deep, approximately triangular shaped base, a proportionately narrow, slightly forward angled shaft and a short tip. Thus, the discrimination of G. poeciliae, based on marginal hook morphology, follows the comments provided for G. costaricensis.Published as part of Rubio-Godoy, Miguel, Paladini, Giuseppe & García-Vásquez, Adriana, 2010, Gyrodactylus jarocho sp. nov. and Gyrodactylus xalapensis sp. nov. (Platyhelminthes: Monogenea) from Mexican poeciliids (Teleostei: Cyprinodontiformes), with comments on the known gyrodactylid fauna infecting poeciliid fish, pp. 1-29 in Zootaxa 2509 on page 22, DOI: 10.5281/zenodo.19603
Gyrodactylus gambusiae Rogers & Wellborn 1965
No full textGyrodactylus gambusiae Rogers & Wellborn, 1965 (Figure 12; Tables 4 and 7) Type host: Gambusia affinis Baird & Girard (“mosquitofish”, “guayacón mosquito”). Site of infection: Fins and body. Type locality: Welaka Lake, Putnam Co., Florida, USA. Type material examined: One paratype (USNPC 908 – 19 / 20). Comments: Ventral bar not visible in paratype. The large open faced, angular marginal hook sickles of G. gambusiae are readily differentiated from those of both G. j a ro c h o sp. nov. and G. xalapensis sp. nov. (Figures 13, 14). The marginal hook sickles of G. gambusiae are morphologically similar to those of Gyrodactylus milleri Harris & Cable, 2000 (all three marginal hook types - see the full description below) and G. turnbulli. The sickle point of G. gambusiae, which quickly narrows abruptly to give a short tip, however, most readily discriminates this species from the latter two, which have longer, more slender sickle points.Published as part of Rubio-Godoy, Miguel, Paladini, Giuseppe & García-Vásquez, Adriana, 2010, Gyrodactylus jarocho sp. nov. and Gyrodactylus xalapensis sp. nov. (Platyhelminthes: Monogenea) from Mexican poeciliids (Teleostei: Cyprinodontiformes), with comments on the known gyrodactylid fauna infecting poeciliid fish, pp. 1-29 in Zootaxa 2509 on page 20, DOI: 10.5281/zenodo.19603
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
Gyrodactylus pictae Cable
No full textGyrodactylus pictae Cable, van Oosterhout, Barson & Harris, 2005 (Figure 18; Tables 4 and 7) Type host: Micropoecilia (= Poecilia) picta Regan (“swamp guppy”). Site of infection: Skin and fins. Type locality: Lower Marianne River, Northern drainage of the Northern Mountain Range, Trinidad. Type material examined: One paratype (BMNH 2004.7.27.2– 5). Comments: The marginal hook sickles of G. p i c t a e have a straight shaft which makes two noticeable deflections in angle towards the point. The point is level with the sickle base giving the sickle a wide aperture which is more open than that of both G. j a ro c h o sp. nov. and G. xalapensis sp. nov. (Figures 19, 20). Although the sickle is of a similar length to that of G. j a ro c h o sp. nov., the sickle base of G. pictae is approximately two thirds the depth of that of G. j a ro c h o sp. nov. The heel of G. pictae is rectangular, the toe drops below the lower level of the heel and the toe bridge is twice the length of that seen in G. j a ro c h o sp. nov. but similar in length to that of G. xalapensis sp. nov. (Figures 19, 20).Published as part of Rubio-Godoy, Miguel, Paladini, Giuseppe & García-Vásquez, Adriana, 2010, Gyrodactylus jarocho sp. nov. and Gyrodactylus xalapensis sp. nov. (Platyhelminthes: Monogenea) from Mexican poeciliids (Teleostei: Cyprinodontiformes), with comments on the known gyrodactylid fauna infecting poeciliid fish, pp. 1-29 in Zootaxa 2509 on page 22, DOI: 10.5281/zenodo.19603
FIGURE 30 in Gyrodactylus jarocho sp. nov. and Gyrodactylus xalapensis sp. nov. (Platyhelminthes: Monogenea) from Mexican poeciliids (Teleostei: Cyprinodontiformes), with comments on the known gyrodactylid fauna infecting poeciliid fish
No full textFIGURE 30. Principal Components Analysis plot (Factor1 vs Factor2) of the 13 point-to-point measurements made on 45 gyrodactylids collected from a range of poeciliid hosts. Separation of the specimens is principally influenced by the hamulus total length (HTL), shaft length (HSL), point length (HPL) and aperture distance (HA) acting along Factor1 in a negative direction, and the inner (CosIHAA) and outer (CosHAA) hamulus angles acting along Factor1 in a positive direction. The total length (MHTL) and the shaft length (MHSL) of the marginal hook are key variables in the separation of specimens along Factor2. The raw ellipses highlight the specimens of Gyrodactylus xalapensis sp. nov. from Heterandria bimaculata Heckel (1), and Gyrodactylus jarocho sp. nov. from Xiphophorus hellerii Heckel (2). Plot codes: a. Gyrodactylus bullatarudis Turnbull, 1956 from Poecilia mexicana Steindachner; b. G. bullatarudis from X. hellerii; c. G. j a ro c h o sp. nov. from X. hellerii; d. G. xalapensis from H. bimaculata; e. G. bullatarudis paratype from Poecilia sphenops Valenciennes; f. Gyrodactylus costaricensis Kritsky & Fritts, 1970 from P. sphenops; g. Gyrodactylus gambusiae Rogers & Wellborn, 1965 from Gambusia affinis Baird & Girard; h. Gyrodactylus pictae Cable, van Oosterhout, Barson & Harris, 2005 from Micropoecilia (=Poecilia) picta Regan; i. Gyrodactylus turnbulli Harris, 1986 from Poecilia reticulata Peters; j. Gyrodactylus poeciliae Harris & Cable, 2000 from Poecilia caucana Steindachner; k. Gyrodactylus milleri Harris & Cable, 2000 from P. caucana; l. Gyrodactylus cytophagus Paperna, 1968 from Aplocheilichthys pumilus Boulenger; m. Gyrodactylus rasini Lucký, 1973 from X. hellerii.Published as part of Rubio-Godoy, Miguel, Paladini, Giuseppe & García-Vásquez, Adriana, 2010, Gyrodactylus jarocho sp. nov. and Gyrodactylus xalapensis sp. nov. (Platyhelminthes: Monogenea) from Mexican poeciliids (Teleostei: Cyprinodontiformes), with comments on the known gyrodactylid fauna infecting poeciliid fish, pp. 1-29 in Zootaxa 2509 on page 12, DOI: 10.5281/zenodo.19603
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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