1,721,078 research outputs found
A new species of Dugesia (Platyhelminthes, Tricladida, Dugesiidae) from the Afromontane forest in South Africa, with an overview of freshwater planarians from the African continent
No full textA new species of the genus Dugesia from the Amatola Mountains in the Eastern Province of South Africa is described,
including a karyological account and notes on its life cycle and reproductive modes. The new species differs from its
congeners in a unique combination of morphological characters of the copulatory apparatus, in particular the central
course of the ejaculatory duct with its terminal opening at the tip of the penis papilla, the elongated seminal vesicle, the
asymmetrical openings of the oviducts into the bursal canal, and the openings of vasa deferentia at about halfway along
the seminal vesicle. In addition, an overview is provided of all freshwater triclads reported from the African continent
including karyological information and notes on reproductive modes
Subterranean aquatic planarians of Sardinia, with a discussion on the penial flagellum and the bursal canal sphincter in the genus Dendrocoelum (Platyhelminthes, Tricladida, Dendrocoelidae)
No full textThe paper provides the first detailed account on the taxonomic richness of the
subterranean freshwater triclads from Sardinia, including the description of four new
species for the genera Dendrocoelum and Phagocata. New records for Dugesia benazzii,
Dugesia sp., Crenobia alpina, and Phagocata sp. are also reported. The three new species
of Dendrocoelum are the first reported for the island of Sardinia. These species display a
bursal canal sphincter and a large adenodactyl with a characteristic anatomy with a zone
of fine circular muscle fibers running through the mesenchyme of its papilla. A detailed
analysis of the structure of the penial flagellum in the genus Dendrocoelum highlighted six
main conditions, some of which have not been previously reported, in regard to the
histology of the tip of the penis papilla and the extent of its inversion. The new species of
Phagocata represents the first species recorded from Italy and the first anophtalmous
species reported from Europe
Integrative taxonomy of a new species of planarian from the Lake Ohrid basin, including an analysis of biogeographical patterns in freshwater triclads from the Ohrid region (Platyhelminthes, Tricladida, Dugesiidae)
No full textA new species of the genus Dugesia is described from the Lake Ohrid region in the western part of the
Balkan Peninsula, forming the first fully documented species description for this genus in the Ohrid
area. The morphological species delimitation is supported by complementary molecular, karyological,
and cytogenetic data available from the literature. Therefore, species delineation is based on a truly
integrative approach. Further, a short account on the degree of freshwater planarian endemicity in the
Ohrid region is provided
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
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