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Post-larval growth in the lateral white muscle of the eel, Anguilla anguilla
No full textThe post-larval growth of lateral white muscle was studied in eels at different stages of post-larval development (glass, yellow and silver eels) by means of histochemical methods for myosin-ATPase (mATPase) activity, immunohistochemistry (for myosin isoforms) and electron microscopy.
Morphological, histo- and immunohistochemical data reveal a uniform appearance of white muscle in glass eels, whereas in following stages the typical mosaic appearance is present. Small-diameter fibres show a more acid-labile mATPase activity than large fibres and react with anti-F, anti-FHC and anti-S sera, but not with anti-SHC serum. In the silver stage, the small fibres tend to decrease in number as the size of the eels increases.
Electron microscopy reveals the presence of satellite cells at every stage: in glass eels there are also ‘activated’ elements showing scarce myofilaments in their cytoplasm; in yellow eels very small fibres are present, enveloped within the basal lamina of well-differentiated muscle fibres; in silver eels there are no fibres showing signs of immaturity.
Presumably the post-larval development of white muscle involves in juvenile eels a substantial recruitment of fibres from the satellite cell population; later the hyperplasia decreases or ceases and hypertrophy remains the only mechanism for muscle growth
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
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
Developmental transitions of myosin isoforms and organisation of the lateral muscle in the teleostDicentrarchus labrax (L.)
No full textInDicentrarchus labrax (the sea bass) the differentiation of lateral muscle fibres occurs at different stages and in different ways in the superficial (red), intermediate (pink) and deep (white) regions of the myotome.
At hatching the myotomes are composed of presumptive white and red fibres, the latter forming a superficial monolayer present only near the transverse septum. At this stage, differences between the fibre types are mainly ultrastructural.
From their different reactions with isoform-specific antibodies to mullet myosin, and the appearance of histochemical mATPase activity, it appears that in both red and white muscle fibres there is a transition in myosin composition from an early larval form (L1R and L1W respectively) to a late larval form (L2R and L2W) and then to the isoforms typical of adult red and white muscle.
The transition from L1W to L2W in the deep muscle occurs very rapidly and early in larval life (between 10 and 28 days), whereas the equivalent transition in the superficial muscle (from L1R to L2R) is a gradual process beginning in fibres near the trasverse septum and spreading hypo- and epi-axially as this layer grows around the deep muscle. The definitive adult forms (AR and AW), distinguishable by the appearance of characteristic histochemical myosin ATPase activity, are present in the superficial red muscle by 80 days, but later in the deep white muscle (by 20 months), respectively.
Compared to the superficial red and deep white muscle, the intermediate (pink) muscle layer first appears relatively late (80 days), but then acquires the histo- and immunohistochemical profile characteristic of the adult form much more rapidly.
The mosaic appearance of the deep white muscle is first seen during larval life. However, at this stage the smaller fibres of the mosaic have a different histo- and immunohistochemical profile from that seen in the adult small white fibres, which may indicate different mechanisms of histogenesis of new fibres in the deep muscle layer in the early and adult stages.
Key words Fish - Muscle development - Myosin - Immunohistochemistry - Histochemistr
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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