1,721,048 research outputs found
Advanced methods and techniques against the degradation of civil structures: Detection, evaluation and retrofitting
No full textTaxonomy and distribution of the genus Tavanicythere Bossio, 1980 (Ostracoda, Leptocytheridae)
No full textThe genus Tavanicythere was established in 1980 by Bossio on the basis of several valves recovered in the Lower Messinian brackish deposits of the Radicondoli area (Volterra Basin, Tuscany, central Italy). Three species were included in this genus: Tavanicythere lepida Bossio (the type species), Tavanicythere etrusca Bossio and Tavanicythere pulchra Bossio. Since then, many other specimens referable to Tavanicythere have been collected from several Neogene Tuscany basins (Volterra, Valdelsa, Cinigiano-Baccinello), but no specific identifications were carried out and they were generally reported in literature as Tavanicythere sp. In this paper we have revised all the collected material. Up to 15 different new taxa have been recognised, even if only 11 are formally established herein as new species, due, in some cases, to the scarcity of valves: Tavanicythere varieornata nov. sp., Tavanicythere persculpta nov. sp., Tavanicythere posteroalata nov. sp. Tavanicythere sulcata nov. sp., Tavanicythere magna nov. sp., Tavanicythere nodosa nov. sp., Tavanicythere armata nov. sp., Tavanicythere ioachinoi nov. sp., Tavanicythere julianii nov. sp., Tavanicythere parva nov. sp. and Tavanicythere irregularis nov. sp. Only few species of Tavanicythere appear to be distributed in different basins, the majority being confined to one basin only. This could be due to particular brackish environmental conditions that triggered basin endemisms. The recovery of new Tavanicythere species lead to enlarge the stratigraphical distribution of this genus, prior limited to the Early Messinian, to the time interval Late Tortonian-Messinian. Tavanicythere seems to be widespread only in the Mediterranean basin and, in particular, in Italy (Tuscany). At present, outside of Italy it has been collected only from the Late Messinian brackish deposits of the Sorbas basin (SE Spain)
New species of Mediocytherideis (Ostracoda, Mediocytherideisinae) in the brackish Messinian of Italy
No full textIn questo lavoro vengono studiati il genere Mediocytherideis Mandelstam, 1956 con i suoi sottogeneri Mediocytherideis s.s. e M. (Sylvestra) Doruk, 1973 e vengono fornite, per entrambi, le diagnosi emendate. Vengono istituite sei nuove specie: Mediocytherideis (Sylvestra) etrusca nov. sp., Mediocytherideis (Sylvestra) fossata nov. sp., Mediocytherideis (Sylvestra) ornata nov. sp., Mediocytherideis (Sylvestra) punctata nov. sp., Mediocytherideis (Sylvestra) sulcata nov. sp. e Mediocytherideis (Sylvestra) tetrafoveolata nov. sp., rinvenute nei sedimenti messiniani salmastri dei bacini di Volterra-Radicondoli e di Velona (Toscana, Italia centrale). Inoltre, a causa dello scarso materiale rinvenuto, sono state lasciate
in nomenclatura aperta tre forme di Mediocytherideis s.l. provenienti dai sedimenti salmastri messiniani del bacino di Velona, dalla sezione del cimitero di Taranta Peligna (Montagna della Majella, Italia centrale) e dalla sezione Trave (Ancona, Italia centrale). Viene effettuata, inoltre, una revisione delle specie di Mediocytherideis s.l. note fino ad oggi in letteratura, ponendo particolare attenzione alla loro distribuzione stratigrafica e, sulla base di questi dati, vengono discusse l’origine e la distribuzione stratigrafica e paleobiogeografica del genere. Il database mostra che sia Mediocytherideis s.s. sia M. (Sylvestra) appaiono più o meno contemporaneamente nell’area mediterranea
e in quella paratetidea durante il Serravalliano, quando i due paleodomini non erano ancora separati. Dopo la chiusura della connessione tra Mediterraneo e Paratetide, avvenuta durante il Serravalliano superiore, Mediocytherideis s.l. continuò ad evolversi, con differenti specie, nelle due paleobioprovince. Nella Paratetide le specie di Mediocytherideis s.l. furono sempre caratteristiche di ambienti salmastri o, nei primi momenti della storia evolutiva del genere, di ambienti marini poco profondi stressati; nel Mediterraneo, al contrario, fin dalla sua prima comparsa il genere diede origine a differenti specie adattate o ad ambienti marini poco profondi o ad ambienti salmastri. Sfortunatamente, le conoscenze troppo frammentarie sulle specie di Mediocytherideis s.l. rendono impossibile definire il centro di origine del genere. Allo stesso tempo, è impossibile stabilire se le specie salmastre mediterranee di Mediocytherideis s.l. si originarono da uno stock mediterraneo o da forme salmastre paratetidee migrate verso ovest attraverso la dispersione passiva.The genus Mediocytherideis Mandelstam, 1956 with its subgenera Mediocytherideis s.s. and M. (Sylvestra) Doruk, 1973 are here revised and the emended diagnosis of the two subgenera are given. Six new species have been introduced: Mediocytherideis (Sylvestra) etrusca nov. sp., Mediocytherideis (Sylvestra) fossata nov. sp., Mediocytherideis (Sylvestra) ornata nov. sp., Mediocytherideis (Sylvestra) punctata nov. sp., Mediocytherideis (Sylvestra) sulcata nov. sp. and Mediocytherideis (Sylvestra) tetrafoveolata nov. sp., coming from the Messinian brackish sediments of the Volterra-Radicondoli and Velona basins (Tuscany, central Italy). Three more taxa are described, left in open nomenclature, coming from the Messinian brackish sediments of the Velona Basin, the Taranta Peligna cemetery section (Majella Mt.,
central Italy) and the Trave Section (Ancona, central Italy).
An overview of the known Mediocytherideis s.l. species is given and the stratigraphic distribution and palaeobiogeography of this genus is discussed. The database shows that both Mediocytherideis s.s. and M. (Sylvestra) appear, more or less at the same time, either in the Mediterranean and in the Paratethys regions during Serravallian, a time interval in which these two palaeodomains were not yet divided. After the closure of the Mediterranean-Paratethys connection, occurred during the late Serravallian, Mediocytherideis s.l. continued to spread in each bioprovinces: in the Paratethys it is characteristic of brackish environments or, at least at the very beginning of its evolutive history, of shallow stressed marine environment; in the Mediterranean, on the contrary, since its appearance the genus gave rise to different species adapted to shallow marine environment or brackish environment. Unfortunately the too much-fragmented knowledge on Mediocytherideis s.l. species prevents the recognition of the centre of origin of the genus. Similarly, it is impossible to establish whether the brackish Mediterranean Mediocytherideis s.l. evolved from a Mediterranean stock or from Paratethyan brackish species migrated westwards by passive dispersal
Nuovi dati sull’evoluzione del Mare Tirreno Settentrionale: Stratigrafia dei sedimenti miocenici dell’Isola di Pianosa.
No full text
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
Il Quaternario della Toscana costiera
No full textAnalisi esaustiva dei depositi quaternari costieri marini e continentali del litorale toscano, con riferimenti all'antico popolamento umano dell'area
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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