1,720,961 research outputs found
Analisi della variabilità di M1 in popolazioni fossili e attuali di Terricola savii (de Sélys-Longchamps 1838) (Arvicolidae, Rodentia)
No full textA late Middle Pleistocene vertebrate assemblage from a fluvial terrace of Fiora river (Northern Latium, Central Italy)
No full textPreliminary analysis of M1 of Late Pleistocene and Recent populations of Terricola savii from Italy (Arvicolidae, Rodentia)
No full textThe main object of this research is the study of the variability degree of the first lower molar in Late Pleistocene and living populations of Terricola savii in Italy (whose conspecificity has been proved by genetic analyses) and its comparison with that of fossil populations (assigned to T. savii on a morphological basis) in order to find a way to attribute isolated fossil remains to specific systematic groups. On this basis, we attempted to establish, through different analyses and direct observations on the occlusal dental surface morphology, the relationships that exists between fossil and living populations, and to verify the existence of a temporal and/or geographic cline
A Late Pleistocene vertebrate assemblage from a fluvial terrace of the Fiora River (Northern Latium, Central Italy)
No full textA fauna of fossil vertebrates collected in an alluvial deposit in the Fiora River, in the Vulsini Volcanic District (locality Ponte San Pietro, Northern Latium, Central Italy) is described. Eighteen species have been collected: four amphibians (Triturus cf. T. vulgaris, Bufo bufo, Bufo viridis and Rana sp.), three reptiles (Testudinata indet., Lacerta gr. L. viridis and Hierophis viridiflavus) and eleven species of mammals (Talpa sp., Crocidura leucodon, Felis silvestris, Capreolus capreolus, ?Dama sp., Cricetus sp., Arvicola sp., Clethrionomys glareolus, Apodemus sylvaticus, Glis glis and Muscardinus avellanarius). The fossil assemblage lived, very probably, in a riparian forested area as indicated by the predominance of C. Glareolus and A. sylvaticus and the presence of glirids, wild cat, roe deer and many amphibians. The evolutionary stage of Arvicola combined to the presence of Cricetus point to an attribution to MIS4 or MIS5b (Late Pleistocene). This biochronological datum fit very well with the radiometric data
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
Testing evolutionary stasis and trends in first lower molar shape of extinct Italian populations of Terricola savii (Arvicolidae, Rodentia) by means of Geometric Morphometrics
No full textExtinct populations of Terricola savii have been investigated in order to analyze evolutionary stasis and correlation of first lower molar shape with climatic proxies by means of geometric morphometrics. Evolutionary stasis, its recognition and explanation are central topics in evolutionary paleobiology. In this study, tooth shape variation of the arvicolid T. savii has been analyzed through time. In addition to explicit multivariate tests of stasis based on landmark and semi-landmark geometric morphometrics, first lower molar M1 shape has been decomposed in orthogonal axes of variation and tested for correlation with climate changes. Multivariate tests were consistent with evolutionary stasis. Yet, according to univariate tests, the dominant dimension of shape variation shows a temporal trend well correlated with a climatic proxy, i.e. δ18O. The remaining variation does not show any trend. Adaptation to current climatic condition might occur even without affecting shape as a whole. Phenotypic plasticity of this species could be invoked to explain evolutionary stasis, as a long time pattern
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
- …
