1,721,096 research outputs found
Newly discovered fossils provide novel insights on the biology of the South American Miocene snake Colombophis Hoffstetter & Rage, 1977
No full textAlfonso-Rojas, Andrés, Vanegas, Rubén D., Mariño-Morejón, Elizabeth, Cadena, Edwin-Alberto (2023): Newly discovered fossils provide novel insights on the biology of the South American Miocene snake Colombophis Hoffstetter & Rage, 1977. Geodiversitas 45 (13): 377-399, DOI: 10.5252/geodiversitas2023v45a1
FIG. 3. — Podocnemis tatacoensis n in A new fossil turtle ends the controversy on the occurrence of the extant genus Podocnemis Wagler, 1830 at the Miocene fauna of La Venta, Colombia
No full textFIG. 3. — Podocnemis tatacoensis n. sp. details of its anatomy: A, B, close-up of the keeled neurals 2-4; C, D, left costal 1 in ventral view, sowing the shape of the axillary scar; E, left posterior margin of the carapace showing the bone predation trauma occurred to the peripherals; F, left peripherals 10-11 where the bone healed from the injury increasing the thickness and smoothing the surface; G, H, view of the right pelvic girdle; I, J, close-up of the three lateral musk foramina of the left hyoplastron-peripherals region. Abbreviations: axs, axillary scar; co, costal; hyo, hyoplastron; ili, ilium; isc, ischium; ker, keel rigde; M, marginal scute; mfo, musk foramina; ne, neural; sp, suprapygal; P, pleural scute; pe, peripheral; pub, pubis; py, pygal; res, resin; V, vertebral scute; xip, xiphiplastron. Scale bars: A, B, E, G, H, 2 cm; C, D, 1 cm; F, I, J, 5 mm.Published as part of Cadena, Edwin-Alberto & Vanegas, Rubén Dario, 2023, A new fossil turtle ends the controversy on the occurrence of the extant genus Podocnemis Wagler, 1830 at the Miocene fauna of La Venta, Colombia, pp. 127-138 in Geodiversitas 45 (3) on page 133, DOI: 10.5252/geodiversitas2023v45a3, http://zenodo.org/record/768229
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
FIG. 5. — Phylogenetic hypotheses including Podocnemis tatacoensis n in A new fossil turtle ends the controversy on the occurrence of the extant genus Podocnemis Wagler, 1830 at the Miocene fauna of La Venta, Colombia
No full textFIG. 5. — Phylogenetic hypotheses including Podocnemis tatacoensis n. sp.: A, strict consensus of 192 most parsimonious trees (MPTs), obtained from the first analysis (all taxa, all morphological characters), tree length (TL) = 1318, consistency index (CI) = 0.275, retention index (RI) = 0.741, see the full tree in Supplementary Data S3 (Appendix 3); B, close up of the Podocnemis clade shown in (A). C, close up of the Podocnemis clade obtained in the strict consensus from the second analysis excluding all fossil Podocnemis except P. tatacoensis n. sp., see the full tree in Supplementary Data S4 (Appendix 4), MPTs = 48, TL = 1310, CI = 0.277, and RI = 0.744. Bootstrap (upper) and Bremer support (lower) indices are shown for some clades in (B) and (C); D, close up of the Podocnemis clade obtained from the total evidence analysis that produced a single MPT, TL = 4225, CI = 0.699, and RI = 0.794, as in the morphology only analyses, P. tatacoensis n. sp. is found to be part of Podocnemis and closer to the extant P. unifilis and the fossil P. negrii. Symbol: *, fossil taxa.Published as part of Cadena, Edwin-Alberto & Vanegas, Rubén Dario, 2023, A new fossil turtle ends the controversy on the occurrence of the extant genus Podocnemis Wagler, 1830 at the Miocene fauna of La Venta, Colombia, pp. 127-138 in Geodiversitas 45 (3) on page 135, DOI: 10.5252/geodiversitas2023v45a3, http://zenodo.org/record/768229
FIG. 10 in Newly discovered fossils provide novel insights on the biology of the South American Miocene snake Colombophis Hoffstetter & Rage, 1977
No full textFIG. 10. — Phylogenetic relationships of Colombophis Hoffstetter & Rage, 1977. Strict consensus tree from 79 most parsimonious trees, bootstrap percentages> 50% are shown below the branches. Major clades: A, Scolecophidia; B, Alethinophidia; C, Uropeltoidea; D, Caenophidia; E, Pythonoidea; F, Booidea.Published as part of Alfonso-Rojas, Andrés, Vanegas, Rubén D., Mariño-Morejón, Elizabeth & Cadena, Edwin-Alberto, 2023, Newly discovered fossils provide novel insights on the biology of the South American Miocene snake Colombophis Hoffstetter & Rage, 1977, pp. 377-399 in Geodiversitas 45 (13) on page 390, DOI: 10.5252/geodiversitas2023v45a13, http://zenodo.org/record/815717
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
- …
