1,721,221 research outputs found
Lo studio degli isotopi del carbonio e dell'azoto per ricostruire cronologia, clima e agricoltura nell'Olocene medio ad Arslantepe (Anatolia) - Carbon and nitrogen isotope analysis reveals chronology, palaeoclimate and agricultural practices at Arslantepe (Turkey) during the mid-Holocene
Full text linkThis PhD project has been carried out on plant remains recovered at the site of Arslantepe (Malatya, Turkey), whose research team the candidate is member. Excavations have been carried out by Sapienza University of Rome since 1961. Chronologically, the site can be placed as early as 4700 BC, when the first settlement so far investigated has been dated. The occupation is exceptionally long-term and continues until historical times.
The archaeobotanical research at Arslantepe has been carried out for 35 years: several studies were focussed on huge amount of charcoal and seed/fruit remains. In the very last years complementary stable carbon isotope records from charred wood and cereal remains of 3400-2000 BC levels were established in order to describe climatic conditions and agricultural practices.
The present research project aims firstly for the improvement of chronological framing by new 14C-AMS dates on plant remains. Secondly, the extension of stable carbon isotope analysis to charcoal and cereal remains from 4700 BC and the establishment of new nitrogen isotope records from cereal grains have to be ensued. As a result, the first high-resolution isotope records from an archaeological site of the Near East for the mid-Holocene have been achieved, displaying more than 2500 years of unfailing climate changes and agronomic conditions behind cultural developments.
Specifically, the manuscript is a collection of several papers on archaeobotanical data from the study site, obtained by the candidate during his PhD. Formats are displayed as journal publications
AMS-11 Conference on Accelerator Mass Spectrometry
No full textPartecipazione al comitato organizzativo nazionale
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
Influence of the 12C(α,γ)16O reaction rate on the evolution of a 15 M⊙ star
No full textIn this paper we present the evolution of various 15M(circle dot) stellar models of solar and subsolar chemical composition, calculated using different values for the C-12(alpha, gamma)O-16 reaction rate. This process influences the evolution of a star because it directly operates during the helium burning and it determines the final abundances of (12)G and O-16 left by this burning. Since this reaction works in a convective environment an analysis of its influence on the evolution of a star cannot be disentangled by the behavior of the convective core. Indeed the final C-12 and O-16 abundances largely depend on a delicate balance between the efficiency of this rate and the treatment of the convective core. We will show some tests which indicate quantitavely this interplay
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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