1,720,961 research outputs found
Pycnogonida
No full textCheck-list online dei Picnogonidi italiani nell'ambito del seguente progetto.
Bologna M.A., Zapparoli M., Oliverio M., Minelli A., Bonato L., Cianferoni F., Stoch F. (eds.), Checklist of the Italian Fauna. Version 1.0. Last update: 2021-05-31. Available at: https://www.lifewatchitaly.eu/en/initiatives/checklist-fauna-italia-en/checklist
The Pycnogonids (Arthropoda, Pycnogonida) of Torrevaldaliga (Tyrrhenian Sea), Italy, with data on Endeis biseriata, new record for the Mediterranean Sea
No full textNew data about the Mediterranean pycnogonids are given. For this contribution, we analysed 315 samples that until now had remained unidentified, collected in 1979–1980 in the Tyrrhenian Sea close to Torrevaldaliga, Italy. We found six species: Ammothella appendiculata, Anoplodactylus californicus, Endeis biseriata, Endeis spinosa, Nymphon gracile and Tanystylum conirostre. Two of them are the subject of taxonomical and faunal remarks: morphological features of Anoplodactylus californicus specimens are reported and discussed, and the first record of Endeis biseriata for the Mediterranean Sea is reported
Is Acerentomon italicum Nosek, 1969 (Protura: Acerentomidae) a species complex?
No full textAcerentomon italicum Nosek, 1969 is the most abundant Protura species in Italy. Two groups of populations
characterized by the different position of a pore on tergite VII were analyzed. Specimens from Austria and from the Italian
provinces of Brescia and Bolzano (Lombardy and Alto Adige, respectively) possess a postero-sub-medial pore (psm);
in specimens from Trento (Trentino), Veneto, Friuli-Venezia Giulia and Liguria the pore is in an antero-sub-lateral (asl)
position. An integrative approach was applied to assess other characters distinguishing these populations. The lengths
of body, head, foretarsus, claw of anterior leg, foretarsal sensilla a and b were measured; in addition some ratios were
calculated: TR (length of foretarsus/length of its claw), BS (distance of sensillum t1 from base of foretarsus/distance of
t1 from foretarsus tip), length of a/foretarsus length, length of b/foretarsus length and length of a/length of b. A geometric
morphometric analysis was performed on the position of setae on tergite VII, selecting as landmarks the bases of setae
A1, A2, A3, P1, P1a, P2, P2a and P3. Nucleotide sequences COI-5P and 28S-D2-D3 of both groups were compared.
Signifi cant differences in the foretarsus and anterior claw length, in the arrangement of setae on tergite VII and in the
barcode sequences COI-5P between the “psm and asl populations” are shown to exist. Based on the results obtained, the
two groups are different, but there is not enough support to differentiate them at the species level
Pycnogonids (Arthropoda: Pycnogonida) of Portofino, Ligurian Sea (North-Western Mediterranean Sea)
No full textPycnogonida collected monthly from September 2017 to August 2018 in the Portofino Marine Protected Area at
0–5 m depth were studied. A total of 499 specimens were collected, 457 of which were identified to species level. These
were classified as belonging to 10 species: Achelia echinata*, Ascorhynchus castelli, Neotrygaeus communis*, Tanystylum
conirostre*, Anoplodactylus angulatus, A. petiolatus, A. pygmaeus*, A. virescens, Callipallene phantoma and C. tiberi*. For
five dominant species (those marked with an asterisk) the annual phenology was outlined. Four hundred and seventeen
additional specimens, collected from the same area and depth range mainly during the 1970s and 1980s were identified to
species level for completeness of information, leading to the addition of Pycnogonum pusillum and Endeis spinosa
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
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