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Sperm ultrastructure in two species of Gyraulus (Gastropoda: Pulmonata: Planorbidae)
No full textSoldatenko, E.V., Shatrov, A.B., Petrov, A.A. (2016): Sperm ultrastructure in two species of Gyraulus (Gastropoda: Pulmonata: Planorbidae). Journal of Natural History 50: 2985-3002, DOI: 10.1080/00222933.2016.1219781, URL: http://dx.doi.org/10.1080/00222933.2016.121978
Figure 4 in Morphology of tube-like threads related to Limnochares aquatica (L., 1758) (Acariformes: Hydrachnidia: Limnocharidae) in the laboratory
No full textFigure 4. (a) Transmission (TEM) and (b) scanning (SEM) electron microscopy of threads of the water mites Limnochares aquatica (L.) from the thread balls. (a) Transverse section of the thread showing a dense core (arrowhead) at some distance from a thick wall (arrow). Scale bar = 1 µm; (b) bunch of the threads possessing a core (arrowheads) enclosed within the thread wall (arrows). Scale bar = 10 µm.Published as part of Shatrov, A.B., Soldatenko, E.V. & Gavrilova, O.V., 2016, Morphology of tube-like threads related to Limnochares aquatica (L., 1758) (Acariformes: Hydrachnidia: Limnocharidae) in the laboratory, pp. 2199-2214 in Journal of Natural History 50 on page 2208, DOI: 10.1080/00222933.2016.1193643, http://zenodo.org/record/399296
Figure 4 in Sperm ultrastructure in two species of Gyraulus (Gastropoda: Pulmonata: Planorbidae)
No full textFigure 4. Longitudinal (LS) and transverse (TS) transmission electron micrograph sections of spermatozoa of Gyraulus (Gyraulus) albus. (a) LS, sperm head at the final stage of maturation. (b, c) LS, internal structure of the acrosomal complex. (d) TS, acrosomal pedestal. (e) TS, basal portion of the nucleus with trapezoid coarse fibres. (f) TS, neck region with trapezoid coarse fibres and a single glycogen mass surrounded by a thin band of mitochondrial derivative. (g) TS, anterior midpiece with triangular coarse fibres and four glycogen helices enclosed within a mitochondrial derivative. (h) LS, posterior portion of the nucleus, neck region and anterior portion of the midpiece. (i) LS, middle portion of the midpiece showing four glycogen helices, mitochondrial derivative and axial complex. (j) TS, middle portion of the midpiece showing three glycogen helices, mitochondrial derivatives and axial complex. (k) TS, middle portion of the midpiece with two glycogen helices, mitochondrial derivative and axoneme. (l) TS, posterior midpiece with a single glycogen helix. (m) TS, posteriorPublished as part of Soldatenko, E.V., Shatrov, A.B. & Petrov, A.A., 2016, Sperm ultrastructure in two species of Gyraulus (Gastropoda: Pulmonata: Planorbidae), pp. 2985-3002 in Journal of Natural History 50 on page 2994, DOI: 10.1080/00222933.2016.1219781, http://zenodo.org/record/518985
Figure 3 in Sperm ultrastructure in two species of Gyraulus (Gastropoda: Pulmonata: Planorbidae)
No full textFigure 3. Longitudinal (LS) and transverse (TS) transmission electron micrograph sections of spermatozoa of Gyraulus (Armiger) crista. (a, b) LS, head of a spermatozoon at the final stage of maturation. (c) LS, internal structure of the acrosomal complex. (d) TS, middle portion of the nucleus. (e) TS, basal portion of the nucleus with trapezoid coarse fibres and a single glycogen mass surrounded by a thin band of mitochondrial derivative. (f) TS, neck region with triangular coarse fibres and four glycogen helices enclosed within the mitochondrial derivative. (g) LS, middle portion of the midpiece with three glycogen helices, mitochondrial derivative and axoneme. (h) TS, middle portion of the midpiece with two glycogen helices, mitochondrial derivative and axoneme. (i) TS, posterior portion of the midpiece with a single glycogen helix. (j) TS, portion of the midpiece without glycogen helices. (k, l) LS, annulus region showing a ring at the tip of the mitochondrial derivative (black arrows) and a cylinder at the anterior end of the glycogen piece (white arrows). (m) TS, glycogen region with the axoneme. (n) TS, axoneme in the tail region with a complete 9 + 2Published as part of Soldatenko, E.V., Shatrov, A.B. & Petrov, A.A., 2016, Sperm ultrastructure in two species of Gyraulus (Gastropoda: Pulmonata: Planorbidae), pp. 2985-3002 in Journal of Natural History 50 on page 2992, DOI: 10.1080/00222933.2016.1219781, http://zenodo.org/record/518985
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
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