1,721,353 research outputs found
Bioerosion on brachiopod shells - a Cenozoic perspective.
No full textIn this study we describe bioerosion traces ascribed to either predation or endo- and epibionts activity in twenty assemblages from the Mediterranean region and Paratethys, spanning in age from the Eocene to Recent. Statistical analysis of the distribution of bioerosion traces among genera and assemblages revealed that there is higher drilling predation intensity on smaller species. Larger species seem to be primarly affected by non-drilling predators. Most variance in type of bioerosion could be related to species’ ecology and body size. Both major categories of bioerosion (etchings and traces of predatory activity) vary considerably among samples. Different genera show sicgnificant differences in the frequency of different bioerosion types. Shell size seems a major factor contributing to these differences
BRYOZOANS AND MICROMORPHIC BRACHIOPODS (LOPHOPHORATA) FROM THE BARTONIAN-PRIABONIAN OF THE ALANO DI PIAVE SECTION (NE ITALY)
No full textThe Alano di Piave section (Veneto region, NE Italy) contains one of the best Tethyan hemipelagic records of the Middle-Late Eocene transition and has been recently proposed as candidate for the Global Stratotype Section and Point (GSSP) of the Priabonian (Agnini et al., 2011). It consists of ~130m of mid bathyal marls with intercalated several silty-sandy and ruditic layers of variable thickness and composition. During micropaleontological investigations, several specimens of bryozoans and brachiopods have been recovered, mostly in correspondence of two bioclastic beds located at +19 and +32m within the Bartonian portion of the section. Such beds include larger foraminifera (nummulitids and orthophragminids) and other bioclasts whose source area was the nearby Lessinian Shelf. Bryozoans commonly occur, but their moderate to poor preservation state often hampers confident taxonomic identification. The bryofaunal composition is identical in both the beds and arborescent cyclostomes dominate in abundance over cheilostomes. Cyclostomes and cheilostomes belong to erect rigid and flexible growth forms, indicating a source area in a quiet environment at about 150-200m of depths. The presence of the encrusting species Vibracella trapezoidea is compatible with such environment, because it frequently encrusted on nummulitids. The Bartonian assemblage from Alano, on the whole, is very similar to the rich Priabonian-Rupelian bryofaunas of the classical shallow-water sections of the Berici Hills and Lessini Mts., West of Alano di Piave (e.g. Braga, 2008).
The brachiopod fauna, mostly recovered from the upper bioclastic bed ("Canova bed", at +32m) consists of six, exclusively micromorphic, species belonging to five genera, i.e. Terebratulina tenuistriata, Orthothyris pectinoides, Lacazella mediterranea, Joania cf. cordata, Argyrotheca cf. cuneata, and Argyrotheca sp. cf. A. crassicostata. The former three species have been already reported from the Late Eocene of NE Italy (Bitner & Dieni, 2005) and are widely distributed throughout whole Europe. The occurrence in the studied assemblage of Joania extends the stratigraphical range of this genus from the Oligocene to the Middle Eocene (Bartonian).
Within the Priabonian portion of the Alano section, from ca. +100m upward, a bispecific, low-density bryozoan assemblage (Batopora rosula + B. stoliczkai) is present. The absence of bioclastic beds or other sedimentary disturbances indicate a genuine, in situ assemblage. Based on benthic foraminiferal assemblages and Recent monospecific or oligospecific assemblages of conescharelliniform (e.g. Moissette 1996), we interpret such Batopora assemblage as characteristic of soft sediments deposited in a full bathyal environment. Such finding probably represents the first record of a deep-water conescharelliniform assemblage in the Eocene of Italy
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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