333 research outputs found

    Empirical Ground-Motion Prediction Equations for Northern Italy Using Weak- and Strong-Motion Amplitudes, Frequency Content, and Duration Parameters

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    The goals of this work are to review the Northern-Italy ground-motion prediction equations (GMPEs) for amplitude parameters and to propose new GMPEs for frequency content and duration parameters. Approximately 10,000 weak and strong waveforms have been collected merging information from different neighboring regional seismic networks operating in the last 30 yr throughout Northern Italy. New ground-motion models, calibrated for epicentral distances ≤100 km and for both local (ML) and moment magnitude (Mw), have been developed starting from a high quality dataset (624 waveforms) that consists of 82 selected earthquakes with ML and Mw up to 6.3 and 6.5, respectively. The vertical component and the maximum of the two horizontal components of motion have been considered, for both acceleration (peak ground horizontal acceleration [PGHA] and peak ground vertical acceleration [PGVA]) and velocity (peak ground horizontal velocity [PGHV] and peak ground vertical velocity [PGVV]) data. In order to make comparisons with the most commonly used prediction equations for the Italian territory (Sabetta and Pugliese, 1996 [hereafter, SP96] and Ambraseys et al. 2005a,b [hereafter, AM05]) the coefficients for acceleration response spectra (spectral horizontal acceleration [SHA] and spectral vertical acceleration [SVA]) and for pseudovelocity response spectra (pseudospectral horizontal velocity [PSHV] and pseudospectral vertical velocity [PSVV]) have been calculated for 12 periods ranging between 0.04 and 2 sec and for 14 periods ranging between 0.04 and 4 sec, respectively. Finally, empirical relations for Arias intensities (IA), Housner intensities (IH), and strong motion duration (DV) have also been calibrated. The site classification based on Eurocode (hereafter, EC8) classes has been used (ENV, 1998, 2002). The coefficients of the models have been determined using functional forms with an independent magnitude decay rate and applying the random effects model (Abrahamson and Youngs, 1992; Joyner and Boore, 1993) that allow the determination of the interevent, interstation, and record-to-record components of variance. The goodness of fit between observed and predicted values has been evaluated using the maximum likelihood approach as in Spudich et al. (1999). Comparing the proposed GMPEs with SP96 and AM05, it is possible to observe a faster decay of predicted ground motion, in particular for distances greater than 25 km and magnitudes higher than 5.0. The result is an improvement in fit of about one order of size for magnitudes spanning from 3.5 to 4.5

    Empirical ground motion prediction equations for northern italy using weak and strong motion amplitudes, frequency content and duration parameters

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    The aims of this work are to review the Northern-Italy ground motion prediction equations (hereinafter GMPEs) for amplitude parameters and to propose new GMPEs for frequency content and duration parameters. Approximately 10.000 weak and strong waveforms have been collected merging information from different neighbouring regional seismic networks operating in the last 30 years throughout Northern Italy. New ground motion models, calibrated for epicentral distances ≤ 100 km and for both local (Ml) and moment magnitude (Mw), have been developed starting from a high quality dataset (624 waveforms) which consists of 82 selected earthquakes with Ml and Mw up to 6.3 and 6.5 respectively. The vertical component and the maximum of the two horizontal components of motion have been considered, for both acceleration (PGHA and PGVA) and velocity (PGHV and PGVV) data. In order to make comparisons with the most commonly used prediction equations for the Italian territory (Sabetta and Pugliese, 1996 and Ambraseys et al. 2005a,b hereinafter named SP96 and AM05) the coefficients for acceleration response spectra (SHA and SVA) and for pseudo velocity response spectra (PSHV and PSVV) have been calculated for 12 periods ranging between 0.04 s and 2 s and for 14 periods ranging between 0.04 s and 4 s respectively. Finally, empirical relations for Arias and Housner Intensities (IA, IH) and strong motion duration (DV) have also been calibrated. The site classification based on Eurocode (hereinafter EC8) classes has been used (ENV, 1998). The coefficients of the models have been determined using functional forms with an independent magnitude decay rate and applying the random effects model (Abrahamson and Youngs, 1992; Joyner and Boore, 1993) that allow the determination of the inter-event, inter-station and record-to-record components of variance. The goodness of fit between observed and predicted values has been evaluated using the maximum likelihood approach as in Spudich et al. (1999). Comparing the proposed GMPEs both with SP96 and AM05 it is possible to observe a faster decay of predicted ground motion, in particular for distances greater than 25 km and magnitudes higher than 5.0. The result is a fit improvement of about one order of size for magnitudes spanning from 3.5 to 4.5

    A microseismic study in a low seismicityarea: the 2001 site-response experimentin the CittĂ  di Castello Basin (Italy)

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    A site response experiment was performed in the basin of CittĂ  di Castello (a small town in Central Italy) in May 2001. This study is part of a project on the evaluation of seismic hazard in seismogenic areas funded by the Gruppo Nazionale Difesa dai Terremoti (GNDT). The experiment consisted of a dense fixed transect configuration with most of the stations recording in continuous mode, and several ambient noise measurements both in single station and in array configuration spread over the investigated area. The dense transect was composed of 26 seismic stations in a crosswise configuration with a maximum inter-station distance of 250 m. The stations were deployed in the southern part of the basin, from the eastern bedrock outcrop to the western edge, across the town. About 70 earthquakes were recorded during 10 days of deployment, generally low magnitude or regional events. We located 23 earthquakes and 17 of them were located using the waveform similarity approach at 4 stations outside the target area. These 4 stations were part of a dense temporary seismic network involved in a previous experiment of the same project, aimed at performing a high-resolution picture of the local seismicity. Delay analysis on the recorded waveforms allowed us to infer the basin geometry at depth and estimate the S-wave velocity of sediments. Moreover, we evaluated relative site response along the E-W transect by performing a standard spectral ratio. Amplification factors up to 9 are found inside the basin; at frequencies above 5 Hz stations closer to the edges show higher amplification, whereas stations located in the middle of the basin, where the alluvial sediments are thicker (CD11-CD14), show higher amplification below 5 Hz. We considered the average amplification in two frequency bands (1-5 Hz and 5-10 Hz), representative of the resonance frequency for 2-3 storey buildings and 1 storey houses,respectively. Our results suggest that the potential hazard for 2-3 storey buildings is higher in the center of the basin (amplification factor up to 6), and for 1 storey houses is higher at the edges (amplification factor up to 5)

    Ground motion models for Molise region (Southern Italy)

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    On October 31st and November 1st, 2002 two moderate earthquakes of moment magnitude Mw=5.7 (INGV-Harvard European-Mediterranean Regional Centroid-Moment tensor project) occurred in southern Italy. After the mainshocks, felt in many municipalities of the Molise and Puglia region, a strong motion and a seismic temporary network were installed in the epicentral area and surrounding regions. The strong motion network was composed by 9 stations, integrating the accelerometers of the permanent Rete Accelerometrica Nazionale (RAN network), and operated until December 2003. The strong motion data set is composed by 195 recordings from 51 earthquakes (2.5<Ml<5.4) recorded by 29 accelerometers (Dipartimento della Protezione Civile et al., 2004). In addition to the strong motion network, several Italian research institutions (Istituto Nazionale di Geofisica e Vulcanologia, INGV; Istituto Nazionale di Oceanografia e Geofisica, INOGS; Dipartimento per lo studio del Territorio e delle sue Risorse, University of Genoa, Dip.Te.Ris) installed a temporary regional network, composed by 35 seismic stations. This network aimed at monitoring and studying the evolution in time and space of the seismic sequence. More than 1900 aftershocks were recorded in the period November 1st - December 5th, 2002 (Chiarabba et al., 2005). The unified velocity-acceleration data set has been considered to derive ground motion models for peak ground acceleration and peak ground velocity for both maximum horizontal and vertical components. The results obtained for the Molise area have been compared with the attenuation pattern of the Umbria-Marche region (central Italy), that was recently investigated by Bindi et al. (2006). The remarkable differences observed indicate the need of a regional attenuation relation for the area and the need of further investigations, to better identify the role of source characteristics, anelastic and geometric attenuation and site effects in the evaluation of peak ground motion values

    Lipoprotein (a) is increased in acute coronary syndromes (unstable angina pectoris and myocardial infarction), but it is not predictive of the severity of coronary lesions

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    Lipoprotein (a) [Lp(a)] concentrations were determined in 365 patients undergoing coronary angiography for stable angina (n = 159), unstable angina (n = 99), recent myocardial infarction (n = 45), and nonischemic heart disease (cardiomyopathy or valvular disease, n = 62, non-IHD). Mean +/- SD and median Lp(a) concentrations in stable angina (29.9 +/- 29.2;22 mg/dl) did not differ from those in non-IHD (26.9 +/- 26.3; 17), but were significantly lower than in patients with unstable angina (52.7 +/- 36.6; 58) and myocardial infarction (44.8 +/- 36.4; 34) (p0.01). Coronary angiography revealed that 261 patients, including 4 patients in the non-IHD group, had significant (or = 50%) coronary lesions. Lp(a) was higher in patients with (41 +/- 35; 32) than in those without (28 +/- 27; 19) angiographic evidence of significant coronary stenosis (p0.05) and showed a weak univariate correlation with the angiographic index (Total Score) of the severity of the disease (r = 0.106;p0.05). However, in the subgroup of 303 patients with stable/unstable angina or myocardial infarction, Lp(a) was predictive neither of angiographic presence nor of severity of coronary disease. Patients were then ranked according to the Total Score values. Among patients with comparable angiographic severity of coronary artery disease, Lp(a) appeared to be remarkably higher in patients with acute ischemic syndromes (unstable angina, myocardial infarction) than in patients with stable angina. In conclusion, Lp(a) was roughly twice as high in acute (unstable angina, myocardial infarction) than in chronic (stable angina) ischemic syndromes, but there was no difference between chronic stable angina and non-IHD.(ABSTRACT TRUNCATED AT 250 WORDS

    p38 MAPK and JNK Antagonistically Control Senescence and Cytoplasmic p16INK4A Expression in Doxorubicin-Treated Endothelial Progenitor Cells

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    Patients treated with low-dose anthracyclines often show late onset cardiotoxicity. Recent studies suggest that this form of cardiotoxicity is the result of a progenitor cell disease. In this study we demonstrate that Cord Blood Endothelial Progenitor Cells (EPCs) exposed to low, sub-apoptotic doses of doxorubicin show a senescence phenotype characterized by increased SA-b-gal activity, decreased TRF2 and chromosomal abnormalities, enlarged cell shape, and disarrangement of F-actin stress fibers accompanied by impaired migratory ability. P16 INK4A localizes in the cytoplasm of doxorubicin-induced senescent EPCs and not in the nucleus as is the case in EPCs rendered senescent by different stimuli. This localization together with the presence of an arrest in G2, and not at the G1 phase boundary, which is what usually occurs in response to the cell cycle regulatory activity of p16INK4A, suggests that doxorubicin-induced p16 INK4A does not regulate the cell cycle, even though its increase is closely associated with senescence. The effects of doxorubicin are the result of the activation of MAPKs p38 and JNK which act antagonistically. JNK attenuates the senescence, p16 INK4A expression and cytoskeleton remodeling that are induced by activated p38. We also found that conditioned medium from doxorubicin-induced senescent cardiomyocytes does not attract untreated EPCs, unlike conditioned medium from apoptotic cardiomyocytes which has a strong chemoattractant capacity. In conclusion, this study provides a better understanding of the senescence of doxorubicin-treated EPCs, which may be helpful in preventing and treating late onset cardiotoxicity

    A microseismic study in a low seismicity area of Italy: the CittĂ  di Castello 2000-2001 experiment

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    Recent seismological studies contribute to better understand the first order characteristics of earthquake occurrence in Italy, identifying the potential sites for moderate to large size earthquakes. Ad hoc passive seismic experiments performed in these areas provide information to focus on the location and geometry of the active faults more closely. This information is relevant for assessing seismic hazard and for accurately constraining possible ground shaking scenarios. The area around the CittĂ  di Castello Basin, in the Northern Apennines (Central Italy), is characterized by the absence of instrumental seismicity (M > 2.5), it is adjacent to faults ruptured by recent and historical earthquakes. To better understand the tectonics of the area, we installed a dense network of seismic stations equipped with broadband and short period seismometers collecting data continuously for 8 months (October 2000-May 2001). The processing of ~ 900 Gbyte of data revealed a consistent background seismicity consisting of very low magnitude earthquakes (ML < 3.2). Preliminary locations of about 2200 local earthquakes show that the area can be divided into two regions with different seismic behaviour: an area to the NW, in between Sansepolcro and CittĂ  di Castello, where seismicity is not present. An area toward the SE, in between CittĂ  di Castello, Umbertide and Gubbio, where we detected a high microseismicity activity. These findings suggest a probable different mechanical behaviour of the two regions. In the latter area, the seismicity is confined between 0 and 8 km of depth revealing a rather well defined east-dipping, low angle fault 35 km wide that cuts through the entire upper crust down to 12-15 km depth. Beside an apparent structural complexity, fault plane solutions of background seismicity reveal a homogeneous pattern of deformation with a clear NE-SW extension

    Diversity of Cardiologic Issues in a Contemporary Cohort of Women With Breast Cancer

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    Background: Women with breast cancer (BC) represent a special population particularly exposed to cardiovascular disease (CVD) risk. However, cardiologic assessment in BC is mostly limited to detection of left ventricular dysfunction cardiotoxicity (LVD-CTX) due to anticancer treatments. Our aim was to comprehensively investigate CV profile and events in a contemporary BC cohort. Methods and Results: Records of BC patients referred for a Cardio-Oncologic evaluation before starting anticancer treatments, between 2016 and 2019, were retrospectively reviewed (n = 508). Information regarding prevalence and control of CV risk factors, and novel CVD diagnoses were extracted. Occurrence of LVD-CTX, CV events other than LVD-CTX and mortality was assessed. Mean age of study population was 64 ± 13 years; 287 patients were scheduled to receive anthracycline and 165 anti-HER2 therapy. Overall, 53% of BC women had ≥2 CV risk factors, and 67% had at least one of arterial hypertension, dyslipidaemia or diabetes mellitus not adequately controlled. Eighteen (4%) patients were diagnosed a previously unknown CVD. Over a mean follow-up of 2.5 ± 1 years, 3% of BC patients developed LVD-CTX, 2% suffered from other CV events and 11% died. CV risk factors were not associated with LVD-CTX, except for family history of CAD. On the contrary, patients with other CV events exhibited a worse CV profile. Those who died more commonly experienced CV events other than LVD-CTX (p = 0.02). Conclusions: BC women show a suboptimal CV risk profile and are at risk of CV events not limited to LVD-CTX. A baseline Cardio-Oncologic evaluation was instrumental to implement CV prevention and to optimize CV therapies

    A microseismic study in a low seismicity area of Italy: the CittĂ  di Castello 2000-2001 experiment

    Get PDF
    Recent seismological studies contribute to better understand the first order characteristics of earthquake occurrence in Italy, identifying the potential sites for moderate to large size earthquakes. Ad hoc passive seismic experiments performed in these areas provide information to focus on the location and geometry of the active faults more closely. This information is relevant for assessing seismic hazard and for accurately constraining possible ground shaking scenarios. The area around the CittĂ  di Castello Basin, in the Northern Apennines (Central Italy), is characterized by the absence of instrumental seismicity (M > 2.5), it is adjacent to faults ruptured by recent and historical earthquakes. To better understand the tectonics of the area, we installed a dense network of seismic stations equipped with broadband and short period seismometers collecting data continuously for 8 months (October 2000-May 2001). The processing of ~ 900 Gbyte of data revealed a consistent background seismicity consisting of very low magnitude earthquakes (ML < 3.2). Preliminary locations of about 2200 local earthquakes show that the area can be divided into two regions with different seismic behaviour: an area to the NW, in between Sansepolcro and CittĂ  di Castello, where seismicity is not present. An area toward the SE, in between CittĂ  di Castello, Umbertide and Gubbio, where we detected a high microseismicity activity. These findings suggest a probable different mechanical behaviour of the two regions. In the latter area, the seismicity is confined between 0 and 8 km of depth revealing a rather well defined east-dipping, low angle fault 35 km wide that cuts through the entire upper crust down to 12-15 km depth. Beside an apparent structural complexity, fault plane solutions of background seismicity reveal a homogeneous pattern of deformation with a clear NE-SW extension

    Il terremoto del 21 giugno 2013 in Lunigiana. Le attivitĂ  del coordinamento Sismiko

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    Il 21 giugno 2013 alle ore 10.33 UTC è stato registrato dalla Rete Sismica Nazionale (RSN) [Amato e Mele, 2008; Delladio, 2011] dell’Istituto Nazionale di Geofisica e Vulcanologia (INGV) un terremoto di magnitudo (ML) 5.2 nel distretto sismico1 denominato “Alpi Apuane” tra i comuni di Minucciano in provincia di Lucca e Fivizzano e Casola in provincia di Massa e Carrara, zona conosciuta come “Lunigiana”. L’evento sismico, localizzato dai sismologi in turno presso la sala di sorveglianza sismica di Roma [Basili, 2011] con coordinate 44.153°N e 10.135° E e una profondità di circa 5 km è stato ben risentito in tutta la penisola centro-settentrionale ed è stato seguito in poche ore da numerosi eventi anche di ML ≥ 3.0 (16 nelle prime 72 ore). Storicamente l’area oggetto della sequenza sismica è stata interessata da numerosi terremoti di magnitudo superiore a 5.0 il più grande dei quali quello avvenuto nel 1920 nella zona della Garfagnana (fonte dati: Catalogo Parametrico dei Terremoti Italiani - CPTI11 [Rovida et al., 2011]), ad una distanza di circa 12 km dal mainshock odierno, interessata anch’essa da una piccola sequenza sismica a gennaio del 2013. In considerazione dell’entità dell’evento e seguendo le procedure definite per le situazioni di emergenza internamente all’INGV anche in accordo con l’Allegato A2 della Convenzione vigente 2012- 20203 fra l’ente e il Dipartimento di Protezione Civile (DPC), è stata attivata la Rete Sismica Mobile della sede INGV di Roma (Re.Mo. [Moretti et al., 2010]). Nell’arco di tempo di poco più un’ora dall’accadimento del mainshock è stata disposta l’installazione di una rete sismica temporanea costituita da sei stazioni a integrazione delle reti sismiche permanenti già presenti in area epicentrale (RSN e Regional Seismic network of North-Western Italy – RSNI [Ferretti et al., 2008; 2010; Eva et al., 2010; Pasta et al., 2011]). Nel contempo sono stati consultati tramite e-mail i referenti delle unità di rete sismica mobile delle altre sedi INGV che nell’ambito del coordinamento “Sismiko” [Moretti et al., 2012] negli ultimi due anni hanno dato la propria disponibilità, in termini di personale e strumentazione, ad intervenire in caso di emergenza sismica; sono stati inoltre contattati i colleghi del Dipartimento di Scienze della Terra, dell’Ambiente e della Vita, dell’Università degli Studi di Genova (DISTAV) i più vicini all’area epicentrale e gestori della RSNI che hanno comunicato loro stessi l’intenzione di installare due stazioni temporanee, una in real-time e una in configurazione stand-alone. In questo lavoro viene descritta l’attività compiuta dalla Rete Sismica Mobile INGV, la tempistica dell’intervento effettuato in sinergia con i colleghi dell’Università di Genova, i dettagli circa l'installazione e la gestione delle stazioni sismiche temporanee nel primo mese di attività e una valutazione del dataset acquisito
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