578 research outputs found

    Il Museo Geofisico di Rocca di Papa: tra divulgazione e ricerca scientifica

    Get PDF
    The Geophysical Museum of Rocca di Papa is located in an historical, three floor building, of the small town Rocca di Papa, twentyfive kilometres from Rome. The edifice was, until 1931, the place of the Geodynamic Observatory, created in 1889 by the famous seismologist Michele Stefano De Rossi. The museum is due to an agreement between the Town Council of Rocca di Papa and the Istituto Nazionale di Geofisica (INGV, one of the most important European Research Institutions operating in geophysics) signed in 2000. After bureaucratic passages and two years of important restoration the museum was open to the public at 26th February 2005. The main aim of the Geophysical Museum is to illustrate how experimental data and information, accumulated by science in the course of time, led to new hypotheses on the internal structure of the Earth. The target of the educational and of the scientific disciplines of the Museum is mainly school students of all ages, but also local residents, and tourists: since its opening, approximately two years ago, the Museum has been visited by more than eight-thousand people. Posters, movie presentations, plastics, games and interactive experiments explain to visitors the main topics of geophysics and the stages of scientific research which led to the modern concept of the Earth internal model. Seismic instruments and games are easily accessible so that the visitor can interact with them: experimental data are recorded in real time and displayed through different monitors placed throughout the rooms. The museum has also a small cinema for three dimensional projections which allow visitors to experience a virtual tour on the Alban Hills, the seismic zone where the museum is located, and also on some other Italian tectonic belts where earthquakes occurred in past. The article introduces the museum and the seismological characteristics of the area, and describes the activities, the exhibits of the Museum and their methodology

    On the use of R-PET strips for the reinforcement of cement mortars

    Get PDF
    We study the alkali resistance and the flexural response of a cement-based mortar reinforced through polyethylene terephthalate (PET) strips obtained through hand cutting of ordinary post-consumer bottles. On considering 1% fiber volume ratio and different strip geometries, we show that the analyzed reinforcing strips owe remarkable alkali resistance and are able to markedly improve the toughness of the base material. Comparisons are established with the outcomes of a recent study on a similar reinforcement technique of a cement-lime mortar

    LA RETE SISMICA DELLA PIANA DI GUIDONIA (LAZIO): DATI PRELIMINARI

    Get PDF
    After the seismic period during 2001-2002 that has interested the Plain of Guidonia, situated about fifteen kilometres NE of Rome, which events greatest resentment reached the V-VI MCS, have been installed a local seismic purchased by Comune of Guidonia-Montecelio (Rm). The seismic network (RLG) consists of three digital seismic stations with distances of each other about 2 kilometers, activated to leave from the June 2004 and equipped with three components 1 Hz sismometer. Subsequently, the RLG has enriched of other four digital stations equipped with three components 5 Hz sismometer This network has like main objective the high quality data that agree a better definition of the seismic local activity. These data, that integrate those of the Seismographic Centralized National Network (SCNN), agreed a better ipocentre location. Network geometriy was chosen so as to give back the RLG an independent structure to carry out reliable seismicity locations that characterizes the plain of Guidonia. Unfortunately, industrial and human activity, increases in considerable manner the seismic noise, giving back difficult the record of small events. For this motive the location of the sites was more times changed, and lately, after a seismic crisis in the northern side of the Mountains Cornicolani, that has presented with the same features of that of 2001 of Guidonia, some stations were moved in the neighboring village of Palombara Sabina (Rm)

    Recent seismicity of the «Acque Albule» travertine basin

    Get PDF
    The seismic period which occurred in a portion of Guidonia Montecelio and Tivoli territory, two towns situated about twenty kilometres NE of Rome, affected four areas with a high density of population: Guidonia, Collefiorito, Villalba and Bagni di Tivoli. Even though the events had a very low magnitude (less than 3.0), local phenomena, like rumbles and strong vibrations of the ground, frightened inhabitants also because some months before (January 26, 2001) in a village named Marcellina situated a few kilometres away from Guidonia, a large sinkhole (600 m) had appeared without fore signals. The «Istituto Nazionale di Geofisica e Vulcanologia» (INGV) installed some digital stations that monitored the seismic phenomena. This paper has the aim to process all the information acquired during the period, both from the micro and macro seismic point of view, in order to explain the phenomenology that involved the area. The synergy of the two methodologies lead us to the conclusion that two different seismotectonic structures originated the events, one in an anti-apenninic direction, the other in a N-S direction

    Occurrence of mycotoxins in extruded commercial dog food

    Get PDF
    The aim of this study was to determine the presence and the level of contamination of the most important mycotoxins (deoxynivalenol, fumonisin B1 and B2, aflatoxin B1, B2, G1 and G2, ochratoxin A and zearalenone) in 48 samples of extruded dry dog food found in the Italian market (24 samples from standard economy lines, 24 of premium lines). Analyses were performed using ultra-performance liquid chromatography coupled to tandem mass spectrometry. Although the concentrations of the mycotoxins in all samples proved to respect the European legislation with regards to animal feed, the analyses revealed a substantial presence of deoxynivalenol, fumonisins and ochratoxin A, with values above the limit of quantification (5 \ub5g/kg) in 100%, 88% and 81% of the samples, respectively. In contrast, aflatoxins and zearalenone contamination proved to be very modest, with 88% and 75% of the samples, respectively, showing concentrations below the corresponding limit of quantification (5 \ub5g/kg for aflatoxins and 10 \ub5g/kg for zearalenone). Moreover, despite a very heterogeneous contamination, the concentration of fumonisins and ochratoxin A was significantly higher in standard foods than in premium ones (491 vs. 80.2 \ub5g/kg dry matter for fumonisin B1; 113 vs. 38.5 \ub5g/kg dry matter for fumonisin B2; 599 vs. 103 \ub5g/kg dry matter for total fumonisins; 23.8 vs. 13.0 \ub5g/kg dry matter for ochratoxin A; P < 0.001). Furthermore, a simultaneous presence of different mycotoxins (at concentrations higher than their limit of quantification) was observed in most of the pet foods analyzed; in particular, 19% of the samples were contaminated by no fewer than two different types of mycotoxins, 52% by three, 25% by four and 2% by all the mycotoxins evaluated. These results revealed the need for further investigation into the potential risk deriving from chronic exposure to low doses of the different types of mycotoxins that pet species are subject to today

    RECENT SEISMICITY (2000-2007) IN THE TIBURTINI-PRENESTINI MOUNTAINS REGION (LATIUM, ITALY)

    Get PDF
    A detailed knowledge of the seismicity distribution enables us to gain a better understanding of the recent tectonic evolution and the present-day state of stress of the Tiburtini and Prenestini Mountains region, whose seismic importance is related with the nearness to the town of Rome. It has been carried out an analysis of the seismicity of the region using the data recorded by the permanent stations belonging to the Italian National Seismic Network (RSNC) from 2000, and subsequently integrated with data of local seismic network from 2003 to 2007. The increase of the number of stations in the last years allow us to obtain better quality earthquake localization as before done. We have produced a large database of re-picked events collecting arrival times of P and S waves of local earthquakes with magnitude larger than 2.0, belonging to the 2000-2007 period. The work is subdivided into three step. The first one consists in the determination of the VP/VS ratio using the modified Wadati method. In the second step we perform the analysis of the 1D velocity model that better approximates the structure of the crust in the studied area using the VELEST code (Kissling et al., 1995). Finally, we have the step with earthquake locations and focal mechanisms computation using the first motion polarities method. Fault plane solutions are selected following the two quality factors defined by the FPFIT code (Reasenberg and Oppenheimer, 1985). For the determination of the regional stress field it is used the focal mechanism inversion method elaborated by Gephart and Forsyth (1984). These results are compared with those available from the historical seismicity that struck the region under study

    Seismicity and seismogenic structures in Central Italy: new insigths from the SLAM passive experiment

    Get PDF
    We investigate the background seismicity of Central Italy in the area including southern Latium, Abruzzi and Molise (SLAM project). Within this region, the central Apenninic chain has been historically affected by many strong earthquakes, some of them very destructive such as the 1349 event (Mw Ëś6.7) located at the border between southern Latium and western Molise, the 1654 event (Mw Ëś6.4) in the southern Latium-Abruzzi area, and the 1805 Boiano earthquake in the northern Matese range (Mw 6.7). The last important seismic sequence occurred in May 1984 in the Comino Valley, southestern Latium (Mw 5.8). The recent activity is characterized by diffuse low-magnitude seismicity, punctuated by localised small sequences during 2009-2012. Our study focuses on the analysis of seismicity recorded in the period 2009-2013. We present earthquake locations and focal mechanism solutions obtained by standard procedures and an optimized regional 1D velocity model based on the Velest algorithm. The waveform data set was collected from the digital recordings of the permanent stations of the Italian national seismic network, the Abruzzi and Molise regional seismic networks, and from a dense seismic survey carried out in the region between November 2011 and May 2013. The temporary network consisted of 17 three-component seismic stations all equipped with Reftek RT130 digitizers and Lennartz 3D/5s sensors. The deployment of this array improved significantly the detection and location of background seismicity. We relocated more than 4300 events with magnitude ML ranging from about 0.5 to 4.2. Earthquakes distribution shows hypocentral depths concentrated within the upper crust, between 2 and 20 km of depth, and is mostly clustered along the Apenninic chain axis. The computed fault-plane solutions generally display normal fault mechanisms, confirming the extensional NE-SW processes active since Pleistocene in the study region

    Educational Game about Drugs for Visually Impaired People: A Comparison between Brazil and Portugal

    Get PDF
    Objective: To validate the educational board game “Drugs: playing fair” for visually impaired people in Brazil and Portugal. Methods: Study of apparent validation carried out in two associations for visually impaired people in Fortaleza, Brazil, and in Porto, Portugal. Thirty-six visually impaired people, 18 from each country, participated in the study. An evaluation tool with 23 items on specifications, content and motivation of the game was applied. Results: The scores awarded in both countries were excellent, with means varying in Brazil from 9.0 to 9.6 and in Portugal, from 8.4 to 9.2. As for the categories and subcategories, the best means in Brazil were: content (9.5); theoretical and methodological consistency (9.6) and concepts/information (9.5). In Portugal, the best means were concepts/information (9.2) and curiosity (9.2). Only two items showed a significant difference: “it allows interaction” (p = 0.024) and “compatible degree of difficulty” (p = 0.012). Conclusion: The educational game on drugs was validated in Brazil and Portugal.info:eu-repo/semantics/publishedVersio

    Seismicity and seismogenic structures of Central Apennines (Italy): constraints on the present-day stress field from focal mechanisms – The SLAM (Seismicity of Lazio-Abruzzo and Molise) project

    Get PDF
    The aim of the SLAM (Seismicity of Lazio, Abruzzo and Molise region) project is to provide new insight on the seismotectonic and seismogenesis of a wide portion of central Italy situated between areas affected by recent destructive events such as the 2009, Mw = 6.3, L’Aquila earthquake to the north and the 2002, Mw = 5.8, Molise earthquake to the east. We present new results for the microseismic activity in the Central Apennines, occurred in the period 2009 – 2013, by analyzing seismogram recordings from two temporary networks of up to 17 stations in combination with data from three networks of permanent stations
    • …
    corecore