1,721,009 research outputs found
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
Emotional information processing and visual evoked brain potentials
No full textVisual evoked potentials to emotional slides presented for 2 sec. were investigated in 13 subjects. 73 emotional slides (pleasant, unpleasant, and neutral) were selected from a standardized set of photographic slides, the 1988 International Affective Picture System of Lang, Ohman, and Vaitl. Visual evoked potentials were recorded from three head locations, frontal, central and parietal (Fz, Cz, and Pz). Analyses were performed in the two latency ranges: 300-400 msec. and 300-500 msec. Analyses showed an arousal effect, as indicated by a quadratic trend, indicating that emotional slides (both pleasant and unpleasant) gave higher cortical positivity than neutral ones, for all components. In addition, in the two latency epochs, larger positivities were found al Pz, compared to Fz and Cz, whereas Fz and Ct did not differ from each other
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
Decline and recovery of the Aptian carbonate factory in the Southern Apennine Carbonate Shelves (southern Italy): Climatic/oceanographic vs. local tectonic controls
No full textThe Cretaceous peri-Tethyan carbonate systems record alternating phases of vigourous development and rapid decay of the shallow-water carbonate factories. After reaching their maximum palaeogeographic extent during the early Bedoulian time, the carbonate factories underwent unhealt episodes in relation to well-known crisis events (OAE1). These events resulted in drowning episodes, as experienced in the northern Tethyan carbonate platforms, or in signals of water stress in the carbonate factories, evidenced by drastic changes in the floro-faunistic assemblages, as experienced in the carbonate platforms of the central-southern Tethyan belt. In interpreting the inception and decay of different carbonate depositional systems, climatic-oceanographic variations together with sea-level oscillations are commonly considered key elements. However, local tectonic controls cannot be ruled out.
In attempts to discriminate among the main factors controlling the evolution of the southern Apennine mid-Cretaceous carbonate system, detailed analyses have been performed on Aptian-Albiano carbonate successions in the Matese Group (southern Apennines). Since the middle Aptian, the analysed successions suggest a scenario characterised by a complex, tectonically driven topography, replacing the previous large tropical shallow-water domain. From the Bedulian-Gargasian transition onwards, the analysed area evolved into subdomains characterised by diversified sedimentological trends.
A tectonic control influenced the Gargasian evolution of the considered area with local evolution into small intraplatform basins bordered by channelised margins. Nevertheless, since the latest Bedulian onward, the studied successions register palaeoecological signals that cannot be linked exclusively with tectonic disturbance episodes because of the coeval appearance of analogous signals at a global scale, including a significant shift in the biological assemblages and an outbreak of organisms indicative of stress conditions in the water mass.
The analysed Gargasian strata show impoverished biota: caprinids totally disappear, both as in situ and storm-related layer components, and hermatypic corals are drastically reduced. Muddy lithofacies prevail in intertidal metric cycles in which cyanobacterial consortia, both in the form of dense laminae and coalescent oncoids, orbitolinids and small gastropods (cerithiids) suggest restricted, nutrient-rich water. Large oncoids of Bacinella irregularis/Lithocodium aggregatus and mollusk (mostly oyster and gastropod) shell fragments significantly contribute to storm-related coarse skeletal intercalations, in which oligotrophic condition-adapted forms are reduced or absent. This pattern suggests generalised conditions of stress in the water mass and in more marginal open areas.
Following the mid-Aptian unproductive episode, characterised by the flourishing of assemblages adapted to mesotrophic-eutrophic conditions, the studied southern Apennines shallow-water domain changed again, with a progressive reduction of the previous mainly aragonite-dominated chlorozoan assemblages and an increase of calcite-dominated skeletal components, including rudists with calcitic outer shell layers. Pioneer biota (e.g., cyanobacteria and polychetes) characteristically marked the first phases of recovery in the still-deteriorated shallow-water domains, rapidly evolving into more complex and differentiated assemblages. The outbreak of nerineid and acteonid gastropods seems to be related to a flourishing of cyanobacterial mats and related microphytae and also to the presence of polychetes. Moreover, the grazing activity of the nerineids favoured the flourishing of oysters and oyster-like condrodonta. Among the rudists, the persistence/radiation of rudist species adapted to a wide range of temperatures and that adopted functional strategies that allowed them to thrive in unstable, open, unsuitable sea bottoms such as Requieniidae and Monopleuridae as well as the first elevator Radiolitidae; this suggests some kind of oceanographic change (e.g., seawater chemistry and/or temperature changes). To date, the rudist ecological constraints have yet to be defined. Nevertheless, on the basis of the associated benthic floro-faunistic assemblage, we can infer the complex environmental parameters in which mesotrophic/eutrophic conditions, presumably coupled with cooler and locally oligophotic conditions, cooperatively modified carbonate factory characteristics
First finding of a fossil fern (Matoniaceae) in the paleontological site of Pietraroja (Benevento, Southern Italy).
No full textEffect of S-adenosyl-L-methionine on physical state of erythrocyte membrane in experimental atherosclerosis.
No full text- …
