1,720,957 research outputs found
Parathethyan ostracod immigrants in Italy during Late Miocene
No full textIn this paper the ostracod assemblages recovered from several brackish Late Miocene Italian deposits have been analysed from a
palaeobiogeographical perspective. During late Tortonian-early Messinian it is possible to recognize in Italy rich ostracod assemblages
characterized by a wide contingent of taxa with central European or Mediterranean affinity, while only few brackish and freshwater ostracods
show Paratethyan affinity. The recognized composition of the ostracod assemblages matches the palaeogeographic setting of the palaeo-
Mediterranean/Paratethys at that moment. In fact during late Tortonian-early Messinian the palaeo-Mediterranean and Paratethysian domains were
divided and, even if the connection via the present Marmara Sea-Strimon Basin was still open, the different salinity between them represented an
ecological barrier, preventing faunal exchanges. Since normal aquatic migration was impossible, it must be assumed that the Paratethyan-like taxa
entered the palaeo-Mediterranean area via passive dispersal by aquatic birds. On the contrary, the ostracod assemblages from the Italian Lago-Mare
deposits show the absolute predominance of Paratethyan taxa, which, according to the known palaeogeographic setting during the late Messinian
Lago-Mare event, could actively migrate from the Paratethys domain, colonizing the palaeo-Mediterranean, whose endemic fauna was severely
impoverished by the Messinian salinity crisis and the following water dilution
Parathethyan ostracod immigrants in Italy during Late Miocene.
No full textDuring Serravallian, the emersion of the Carpathians and of the Alpine foreland domain closed the northern connection between the western and the eastern Tethys. In the late Miocene this latter became subdivided into several basins (Vienna Basin, Pannonian Basin, Dacic Basin, Ponto-Euxinic Basin and Caspian-Aral Basin) which, due to the freshwater input from several important rivers, were progressively characterised by brackish waters. The connection via the present Dardanelli straight was still open but the different salinity between western and eastern Tethys represented an ecological barrier, preventing the faunistic exchanges and causing the onset of two different Late Miocene bioprovinces: the Paleomediterranean bioprovince to the west and the Paratethyan bioprovince to the east.Notwithstanding the Late Miocene isolation of Paleomediterranean from Paratethys, during Late Tortonian-early Messinian it is possible to recognise in Italy few brackish and freshwater ostracods with Paratethyan affinity. The palaeogeography of the area prevents to suppose a normal aquatic migration, and, indeed, the distribution of several Paratethyan genera seems disjuncted. In this case, only a passive dispersal by aquatic birds can be claimed. Paratethyan genera transported in Italy are Camptocypria (Sirmiella), Bakunella, Propontoniella, Labiatocandona, Zalanyiella (all included in the Subfamily Candoninae), Loxoconchissa s.s. and Loxoconchissa (Loxocaspia), included in Family Loxoconchidae and Amnicythere (and may be Chartocythere and Mediocytherideis) included in Family Leptocytheridae.During the latest Messinian lago-mare event, the closure of the Atlantic-Mediterranean connection and the subsequent humid global climate phase caused a salinity lowering of the Paleomediterranean waters. The ecological barrier between Paleomediterranean and Paratethys was disrupted and an important contingent of Paratethyan ostracods migrated westwards colonising the Paleomediterranean, whose endemic fauna was severely impoverished by the Messinian salinity crisis and the following water dilution. The Italian (and Paleomediterranean) latest Messinian lago-mare deposits are characterised by Paratethyan species such as Caspiocypris pontica, Lineocypris cf. L. fossulata, Lineocypris cf. L. hodonensis, Pontoniella pontica, Zalanyiella venusta, Amnicythere accicularia, Amnicythere anormalis, Amnicythere cellula, Amnicythere costata, Amnicythere idonea, Amnicythere pontica, Amnicythere lata, Amnicythere litica, Amnicythere multituberculata, Amnicythere palimpsesta, Amnicythere propinqua, Amnicythere cf. A. rosalinae, Amnicythere subcaspia, Euxinocythere (Maeotocythere) praebaquana, Euxinocythere (Maeotocythere) bosqueti, Loxoconcha (Loxoconcha) eichwaldi, Loxoconcha (Loxoconcha) muelleri, Loxoconcha rhombovalis, Loxoconcha cf. L. schweyeri, Loxocorniculina djafarovi, Pseudocythere limata, Cytherura pyrama, Tyrrhenocythere ruggierii, Tyrrhenocythere pontica
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
The end of the “Lago-mare” time in the SE Valdelsa Basin (Central Italy) between local tectonism and regional sea-level rise.
No full textA multi-disciplinary study has been carried out on a Late Neogene succession
exposed in the SE portion of the Valdelsa Basin (Strolla Creek, Central Italy).
Th e succession consists of upper Tortonian-Messinian sediments, unconformably
overlain by uppermost Messinian-Pliocene deposits, accumulated in alluvial,
lacustrine and marine environments. Previous studies on this succession
hypothesized a sudden marine fl ooding of the upper Messinian Lago-Mare realm
in the earliest Zanclean in apparent agreement with the Mio-Pliocene transitionrecorded elsewhere in the Mediterrranean Basin. Data from this study suggest
a more complex stratigraphy recording a local depositional evolution possibly
driven by interference between uplift, relief denudation and eustacy. Th e sediments
encompassing the Mio-Pliocene transition have been included into the
Borro Strolla synthem, furtherly subdivided into three sub-synthems. Th e Borro
Strolla synthem has been dated as uppermost Messinian-earliest Zanclean based
on the integration of physical stratigraphy, facies analysis and biochronology of
non-marine fossil assemblages in part documented for the fi rst time
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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