1,720,965 research outputs found
The late-Antiquity environmental crisis in Emilia Region (Po river plain, Northern Italy): geoarchaeological evidence and paleoclimatic considerations
No full textFor about four decades in Italy local, scientific literature has occasionally dealt with fluvial avulsions, suggesting they should be considered as genetically linked to a peculiar climatic worsening that occurred in the late-6th century AD (the so-called “Paul the Deacon Deluge”). Research performed by the Soprintendenza per i Beni Archeologici dell’Emilia-Romagna over the last few years has allowed us to better define the timing of a more articulated alluvial history, mainly concerning the Roman Imperial age and Late-Antiquity (1st-6th century AD). The main stratigraphic details of fourteen selected archaeological excavation sites (eleven recently surveyed and three reviewed from the literature) performed in the cities of Modena, Bologna and related surroundings have been summarized. Eleven 14C datings, ranging between the years 130 AD and 810 AD, allowed us to chronologically delimit a first frame for the riverbed network behaviour during ancient times in the central part of the region. The alluvial process appeared to be continuous throughout the time span examined. The fan trench was the most sensitive reach of the river system. It started to aggrade during the 4th century AD, during the 5th century AD and probably after the end of the 6th century AD, a number of avulsions occurred. This indicates that the fluvial system was in a metastable equilibrium whose behavioural threshold was finally overcome. Hence, the importance of the supposed year 589 AD crisis (the “Deluge”) appears to be less than that previously supposed. The riverbed aggradation became evident immediately after the Roman empire’s economic and demographic crisis of the 3rd century AD, and it was probably due to the loss of the land preservation systems once created in the mountain catchment areas. The long duration of the aggradation phase suggests that more than one human settlement phase in the minor catchment areas and/or a minor climatic worsening pulse probably occurred during the 5th century AD. The starting of the aggradation also coincided with the end of the Petit Maclu 1 high level phase of the European lakes. Notwithstanding this, the climate’s role as a forcing co-factor can still be hard to evaluate positively due to the lack of local climatic proxy data
Human-landscape interactions in the Bologna area (northern Italy) during the mid-late Holocene, with focus on the Roman period
No full textIntegrated sedimentological and archaeological investigations of mid-late Holocene deposits from the subsurface of Bologna elucidate the complex relationship among urban settlement, human society, geomorphology and climate change at the southern margin of the Po Plain. Above the Pleistocene-Holocene unconformity, the Holocene succession forms an intricate mosaic of alluvial deposits. Two palaeosols, spanning between about 8000-5000 cal. yr BP and 3200-1500 cal. yr BP, respectively, represent the most prominent stratigraphic markers across the study units. A huge amount of archaeological remains from the younger palaeosol enables the identification of an uninterrupted sequence of settlements from the Early Iron Age to the Late Roman period. The first permanent settlements of Iron Age took place in a topographically elevated region protected from flooding. The onset of paedogenesis during this period reflects the radical transformation of the environment by human settlements through widespread control of the river network and setting of regular patterns of irrigation channels. A period of exceptional climate stability characterized the expansion of the Roman Empire. This phase is testified by a wealth of exceptionally preserved archaeological material, including buildings, cemetery sites, streets and irrigation channels. Subsurface correlations of the Roman palaeosol enable detailed reconstruction of the Roman topography, with special focus on fluvial paths and communication routes. The decline of the Roman Empire, hit by a devastating epidemic and the barbarian invasions, was paralleled by a phase of climatic deterioration, resulting in the abandonment of rural lands and degradation of the river network, which ultimately favoured the burial of Roman settlement
A micro-Raman archaeometric approach to Roman wall paintings
No full textInfrared and Raman spectra have been recorded on the surface of plasters from Regium Lepidi (Reggio Emilia, Italy). A palette has been identified, that can be compared with the ones from the nearby towns of the Roman Empire, but some peculiarities can be outlined. Some of the pigments could come from the territory, even though the techniques could be ascribed to those usually present in the 1st century a.c
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
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