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A small L-shaped short-period seismic array was set up at Etna Volcano to measure the wave velocity and the incoming azimuth of the volcanic tremor generated by the volcanic activity at Etna in non eruptive-conditions. Cross-correlation techniques were used to measure the phase-shifts between the array stations. An approximately N-S direction of the propagation direction was estimated, coincident with the azimuth of the crater area of Etna. An apparent velocity of less than 500 m/s was estimated, suggesting a surface propagation of the tremor waves. Spectral analysis, confirming previous results, shows velocity spectra peaked at approximately 2 Hz. A localized source, coincident with the crater area, agrees with our data and could generate the volcanic tremor at Etna in non-eruptive stages.

A geophysical survey was performed at the Roman Amphitheatre of Catania with the aim to study the lithological features of the foundation subsoil of the Amphitheatre and to identify possible underground voids, buried crypts and other heterogeneities. The survey consisted of a number of georadar prospections and of three mechanical drillings. In addition it was experimented a non-invasive technique (passive seismic stratigraphy), which allows to retrieve information on subsoil stratigraphy and on possible seismic site effects. The survey allowed to establish 1) the presence of clays below superficial lava layers in the foundation soil of the Amphitheatre, 2) the presence of 2-D structures below the external ambulatory and 3) the natural resonance frequencies of the structure and of the subsoil in the area of investigation.

Advances in volcano monitoring and forecasting need a multidisciplinary collaborative framework. In light of this, a Bayesian Event Tree (BET) approach was performed by the application of the BET for Eruption Forecasting (BET_EF) code to analyze the space-time distribution of the volcanic activity of Mount Etna from 2001-2005. First, a reliable monitoring dataset was set up after some sessions to elicit geophysical, volcanological and geochemical 'precursor' parameters. A constant unrest probability of 100%, with a magma involvement usually greater than 95%, was computed throughout the time period analyzed. Eruption probabilities higher than 90% were estimated a few days before the onsets of the 2001 and 2002-2003 flank eruptions. Values slightly higher than 75% were observed during the lava fountaining period in June-July 2001. However, the probabilities flattened to around 30% for the 2004-2005 flank eruption. With suitable data, a good depiction of the actual location of the eruptive scenario for the 2001 and 2002-2003 events was provided. Conversely, the size of the eruptions was not indicated. © 2011 by the Istituto Nazionale di Geofisica e Vulcanologia. All rights reserved.

Six studies (N = 491) investigated the inductive potential of nouns versus adjectives in person perception. In the first 5 studies, targets were either described by an adjective (e.g., Mark is homosexual) or by the corresponding noun (e.g., Mark is a homosexual) or by both (Study 3). The authors predicted and found that nouns, more so than adjectives, (a) facilitate descriptor-congruent inferences but inhibit incongruent inferences (Studies 1-3), (b) inhibit alternative classifications (Study 4), and (c) imply essentialism of congruent but not of incongruent preferences (Study 5). This was supported for different group memberships and inclinations (athletics, arts, religion, sexual preference, drinking behavior, etc.), languages (Italian and German), and response formats, suggesting that despite the surface similarity of nouns and adjectives, nouns have a more powerful impact on person perception. Study 6 investigated the inverse relationship, showing that more essentialist beliefs (in terms of a genetic predisposition rather than training) lead speakers to use more nouns and fewer adjectives. Possible extensions of G. R. Semin and K. Fiedler's (1988) linguistic category model and potential applications for language use in intergroup contexts are discussed.

The correlation between destructive shallow local earthquakes (Io≧IX) and the largest eruptions (volume ≧ 107 m3), has been tested at Mount Etna volcano for the period 1600 to the present. These seismic events are found to be linked at a statistically significant level lower than 0.01 to the end of eruptions confirming previous results by Nercessian, Hirn & Sapin (1991). Copyright © 1994, Wiley Blackwell. All rights reserved