919 resultados para Villa of Horace (Licenza, Italy)


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Liver transplantation is the only definitive treatment for transthyretin amyloidosis, with an excellent 5-year survival in endemic countries where the Met30 mutation is predominant. We report our experience of liver transplantation for transthyretin amyloidosis. We reviewed the clinical records of 17 transplanted patients (11 males, 6 females; age at liver transplant: 45.7±11.7 years). We had a wide spectrum of non-Met30 mutations (52.9%), with a predominance of Gln89 (23.5%). Five-year survival after transplantation was 43.8%; at multivariate analysis, both non-Met30 mutations (HR 17.3, 95% CI 1.03-291.7) and modified BMI (HR 0.50, 95% CI 0.29-0.87) showed significant and independent prognostic roles (P=0.048 and P=0.015, respectively). Five out of the 9 non-Met30 carriers received combined heart transplantation because of severe cardiomyopathy; they showed a trend towards a better prognosis vs. the 4 patients who did not receive combined heart transplantation (although not statistically significant; P=0.095). At follow-up, no significant improvement of transthyretin amyloidosis manifestations was observed. The results of liver transplantation for transthyretin amyloidosis in our population are poorer than those reported in the literature probably because of the high prevalence of non-Met30 mutations.

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The interactions between outdoor bronzes and the environment, which lead to bronze corrosion, require a better understanding in order to design effective conservation strategies in the Cultural Heritage field. In the present work, investigations on real patinas of the outdoor monument to Vittorio Bottego (Parma, Italy) and laboratory studies on accelerated corrosion testing of inhibited (by silane-based films, with and without ceria nanoparticles) and non-inhibited quaternary bronzes are reported and discussed. In particular, a wet&dry ageing method was used both for testing the efficiency of the inhibitor and for patinating bronze coupons before applying the inhibitor. A wide range of spectroscopic techniques has been used, for characterizing the core metal (SEM+EDS, XRF, AAS), the corroded surfaces (SEM+EDS, portable XRF, micro-Raman, ATR-IR, Py-GC-MS) and the ageing solutions (AAS). The main conclusions were: 1. The investigations on the Bottego monument confirmed the differentiation of the corrosion products as a function of the exposure geometry, already observed in previous works, further highlighting the need to take into account the different surface features when selecting conservation procedures such as the application of inhibitors (i.e. the relative Sn enrichment in unsheltered areas requires inhibitors which effectively interact not only with Cu but also with Sn). 2. The ageing (pre-patination) cycle on coupons was able to reproduce the relative Sn enrichment that actually happens in real patinated surfaces, making the bronze specimens representative of the real support for bronze inhibitors. 3. The non-toxic silane-based inhibitors display a good protective efficiency towards pre-patinated surfaces, differently from other widely used inhibitors such as benzotriazole (BTA) and its derivatives. 4. The 3-mercapto-propyl-trimethoxy-silane (PropS-SH) additivated with CeO2 nanoparticles generally offered a better corrosion protection than PropS-SH.

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The work undertaken in this PhD thesis is aimed at the development and testing of an innovative methodology for the assessment of the vulnerability of coastal areas to marine catastrophic inundation (tsunami). Different approaches are used at different spatial scales and are applied to three different study areas: 1. The entire western coast of Thailand 2. Two selected coastal suburbs of Sydney – Australia 3. The Aeolian Islands, in the South Tyrrhenian Sea – Italy I have discussed each of these cases study in at least one scientific paper: one paper about the Thailand case study (Dall’Osso et al., in review-b), three papers about the Sydney applications (Dall’Osso et al., 2009a; Dall’Osso et al., 2009b; Dall’Osso and Dominey-Howes, in review) and one last paper about the work at the Aeolian Islands (Dall’Osso et al., in review-a). These publications represent the core of the present PhD thesis. The main topics dealt with are outlined and discussed in a general introduction while the overall conclusions are outlined in the last section.

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Different tools have been used to set up and adopt the model for the fulfillment of the objective of this research. 1. The Model The base model that has been used is the Analytical Hierarchy Process (AHP) adapted with the aim to perform a Benefit Cost Analysis. The AHP developed by Thomas Saaty is a multicriteria decision - making technique which decomposes a complex problem into a hierarchy. It is used to derive ratio scales from both discreet and continuous paired comparisons in multilevel hierarchic structures. These comparisons may be taken from actual measurements or from a fundamental scale that reflects the relative strength of preferences and feelings. 2. Tools and methods 2.1. The Expert Choice Software The software Expert Choice is a tool that allows each operator to easily implement the AHP model in every stage of the problem. 2.2. Personal Interviews to the farms For this research, the farms of the region Emilia Romagna certified EMAS have been detected. Information has been given by EMAS center in Wien. Personal interviews have been carried out to each farm in order to have a complete and realistic judgment of each criteria of the hierarchy. 2.3. Questionnaire A supporting questionnaire has also been delivered and used for the interviews . 3. Elaboration of the data After data collection, the data elaboration has taken place. The software support Expert Choice has been used . 4. Results of the Analysis The result of the figures above (vedere altro documento) gives a series of numbers which are fractions of the unit. This has to be interpreted as the relative contribution of each element to the fulfillment of the relative objective. So calculating the Benefits/costs ratio for each alternative the following will be obtained: Alternative One: Implement EMAS Benefits ratio: 0, 877 Costs ratio: 0, 815 Benfit/Cost ratio: 0,877/0,815=1,08 Alternative Two: Not Implement EMAS Benefits ratio: 0,123 Costs ration: 0,185 Benefit/Cost ratio: 0,123/0,185=0,66 As stated above, the alternative with the highest ratio will be the best solution for the organization. This means that the research carried out and the model implemented suggests that EMAS adoption in the agricultural sector is the best alternative. It has to be noted that the ratio is 1,08 which is a relatively low positive value. This shows the fragility of this conclusion and suggests a careful exam of the benefits and costs for each farm before adopting the scheme. On the other part, the result needs to be taken in consideration by the policy makers in order to enhance their intervention regarding the scheme adoption on the agricultural sector. According to the AHP elaboration of judgments we have the following main considerations on Benefits: - Legal compliance seems to be the most important benefit for the agricultural sector since its rank is 0,471 - The next two most important benefits are Improved internal organization (ranking 0,230) followed by Competitive advantage (ranking 0, 221) mostly due to the sub-element Improved image (ranking 0,743) Finally, even though Incentives are not ranked among the most important elements, the financial ones seem to have been decisive on the decision making process. According to the AHP elaboration of judgments we have the following main considerations on Costs: - External costs seem to be largely more important than the internal ones (ranking 0, 857 over 0,143) suggesting that Emas costs over consultancy and verification remain the biggest obstacle. - The implementation of the EMS is the most challenging element regarding the internal costs (ranking 0,750).

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In this research work I analyzed the instrumental seismicity of Southern Italy in the area including the Lucanian Apennines and Bradano foredeep, making use of the most recent seismological database available so far. I examined the seismicity occurred during the period between 2001 and 2006, considering 514 events with magnitudes M ≥ 2.0. In the first part of the work, P- and S-wave arrival times, recorded by the Italian National Seismic Network (RSNC) operated by the Istituto Nazionale di Geofisica e Vulcanologia (INGV), were re-picked along with those of the SAPTEX temporary array (2001–2004). For some events located in the Upper Val d'Agri, I also used data from the Eni-Agip oil company seismic network. I computed the VP/VS ratio obtaining a value of 1.83 and I carried out an analysis for the one-dimensional (1D) velocity model that approximates the seismic structure of the study area. After this preliminary analysis, making use of the records obtained in the SeSCAL experiment, I incremented the database by handpicking new arrival times. My final dataset consists of 15,666 P- and 9228 S-arrival times associated to 1047 earthquakes with magnitude ML ≥ 1.5. I computed 162 fault-plane solutions and composite focal mechanisms for closely located events. I investigated stress field orientation inverting focal mechanism belonging to the Lucanian Apennine and the Pollino Range, both areas characterized by more concentrated background seismicity. Moreover, I applied the double difference technique (DD) to improve the earthquake locations. Considering these results and different datasets available in the literature, I carried out a detailed analysis of single sub-areas and of a swarm (November 2008) recorded by SeSCAL array. The relocated seismicity appears more concentrated within the upper crust and it is mostly clustered along the Lucanian Apennine chain. In particular, two well-defined clusters were located in the Potentino and in the Abriola-Pietrapertosa sector (central Lucanian region). Their hypocentral depths are slightly deeper than those observed beneath the chain. I suggest that these two seismic features are representative of the transition from the inner portion of the chain with NE-SW extension to the external margin characterized by dextral strike-slip kinematics. In the easternmost part of the study area, below the Bradano foredeep and the Apulia foreland, the seismicity is generally deeper and more scattered and is associated to the Murge uplift and to the small structures present in the area. I also observed a small structure NE-SW oriented in the Abriola-Pietrapertosa area (activated with a swarm in November 2008) that could be considered to act as a barrier to the propagation of a potential rupture of an active NW-SE striking faults system. Focal mechanisms computed in this study are in large part normal and strike-slip solutions and their tensional axes (T-axes) have a generalized NE-SW orientation. Thanks to denser coverage of seismic stations and the detailed analysis, this study is a further contribution to the comprehension of the seismogenesis and state of stress of the Southern Apennines region, giving important contributions to seismotectonic zoning and seismic hazard assessment.

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A finite-strain study in the Gran Paradiso massif of the Italian Western Alps has been carried out to elucidate whether ductile strain shows a relationship to nappe contacts and to shed light on the nature of the subhorizontal foliation typical of the gneiss nappes in the Alps. The Rf/_ and Fry methods used on feldspar porphyroclasts from 143 augengneiss and 11 conglomerate samples of the Gran Paradiso unit (upper tectonic unit of the Gran Paradiso massif), as well as, 9 augengneiss (Erfaulet granite) and 3 quartzite conglomerate samples from the underlying Erfaulet unit (lower unit of the Gran Paradiso massif), and 1 sample from mica schist. Microstructures and thermobarometric data show that feldspar ductility at temperatures >~450°C occurred only during high-pressure metamorphism, when the rocks were underplated beneath the overriding Adriatic plate. Therefore, the finite-strain data can be related to high-pressure metamorphism in the Alpine subduction zone. The augen gneiss was heterogeneously deformed and axial ratios of the strain ellipse in XZ sections range from 2.1 to 69.8. The long axes of the finite-strain ellipsoids trend W/WNW and the short axes are subvertical associated with a subhorizontal foliation. The strain magnitudes do not increase towards the nappe contacts. Geochemical work shows that the accumulation of finite strain was not associated with any significant volume strain. Hence, the data indicate flattening strain type in the Gran Paradiso unit and constrictional strain type in the Erfaulet unit and prove deviations from simple shear. In addition, electron microprobe work was undertaken to determine if the analysed fabrics formed during high-P metamorphism. The chemistry of phengites in the studied samples suggests that deformation and final structural juxtaposition of the Gran Paradiso unit against the Erfaulet took place during high-pressure metamorphism. On the other hand, nappe stacking occurred early during subduction probably by brittle imbrication and that ductile strain was superimposed on and modified the nappe structure during high-pressure underplating in the Alpine subduction zone. The accumulation of ductile strain during underplating was not by simple shear and involved a component of vertical shortening, which caused the subhorizontal foliation in the Gran Paradiso massif. It is concluded that this foliation formed during thrusting of the nappes onto each other suggesting that nappe stacking was associated with vertical shortening. The primary evidence for this interpretation is an attenuated metamorphic section with high-pressure metamorphic rocks of the Gran Paradiso unit juxtaposed against the Erfaulet unit. Therefore, the exhumation during high-pressure metamorphism in the Alpine subduction zone involved a component of vertical shortening, which is responsible for the subhorizontal foliation within the nappes.

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The topic of my Ph.D. thesis is the finite element modeling of coseismic deformation imaged by DInSAR and GPS data. I developed a method to calculate synthetic Green functions with finite element models (FEMs) and then use linear inversion methods to determine the slip distribution on the fault plane. The method is applied to the 2009 L’Aquila Earthquake (Italy) and to the 2008 Wenchuan earthquake (China). I focus on the influence of rheological features of the earth's crust by implementing seismic tomographic data and the influence of topography by implementing Digital Elevation Models (DEM) layers on the FEMs. Results for the L’Aquila earthquake highlight the non-negligible influence of the medium structure: homogeneous and heterogeneous models show discrepancies up to 20% in the fault slip distribution values. Furthermore, in the heterogeneous models a new area of slip appears above the hypocenter. Regarding the 2008 Wenchuan earthquake, the very steep topographic relief of Longmen Shan Range is implemented in my FE model. A large number of DEM layers corresponding to East China is used to achieve the complete coverage of the FE model. My objective was to explore the influence of the topography on the retrieved coseismic slip distribution. The inversion results reveals significant differences between the flat and topographic model. Thus, the flat models frequently adopted are inappropriate to represent the earth surface topographic features and especially in the case of the 2008 Wenchuan earthquake.

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Most basaltic volcanoes are affected by recurrent lateral instabilities during their evolution. Numerous factors have been shown to be involved in the process of flank destabilization occurring over long periods of time or by instantaneous failures. However, the role of these factors on the mechanical behaviour and stability of volcanic edifices is poorly-constrained as lateral failure usually results from the combined effects of several parameters. Our study focuses on the morphological and structural comparison of two end-member basaltic systems, La Reunion (Indian ocean, France) and Stromboli (southern Tyrrhenian sea, Italy). We showed that despite major differences on their volumes and geodynamic settings, both systems present some similarities as they are characterized by an intense intrusive activity along well-developed rift zones and recurrent phenomena of flank collapse during their evolution. Among the factors of instability, the examples of la Reunion and Stromboli evidence the major contribution of intrusive complexes to volcano growth and destruction as attested by field observations and the monitoring of these active volcanoes. Classical models consider the relationship between vertical intrusions of magma and flank movements along a preexisting sliding surface. A set of published and new field data from Piton des Neiges volcano (La Reunion) allowed us to recognize the role of subhorizontal intrusions in the process of flank instability and to characterize the geometry of both subvertical and subhorizontal intrusions within basaltic edifices. This study compares the results of numerical modelling of the displacements associated with high-angle and low-angle intrusions within basaltic volcanoes. We use a Mixed Boundary Element Method to investigate the mechanical response of an edifice to the injection of magmatic intrusions in different stress fields. Our results indicate that the anisotropy of the stress field favours the slip along the intrusions due to cointrusive shear stress, generating flank-scale displacements of the edifice, especially in the case of subhorizontal intrusions, capable of triggering large-scale flank collapses on basaltic volcanoes. Applications of our theoretical results to real cases of flank displacements on basaltic volcanoes (such as the 2007 eruptive crisis at La Reunion and Stromboli) revealed that the previous model of subvertical intrusions-related collapse is a likely mechanism affecting small-scale steeply-sloping basaltic volcanoes like Stromboli. Furthermore, our field study combined to modelling results confirms the importance of shallow-dipping intrusions in the morpho-structural evolution of large gently-sloping basaltic volcanoes like Piton de la Fournaise, Etna and Kilauea, with particular regards to flank instability, which can cause catastrophic tsunamis.

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The primary objective of this thesis is to obtain a better understanding of the 3D velocity structure of the lithosphere in central Italy. To this end, I adopted the Spectral-Element Method to perform accurate numerical simulations of the complex wavefields generated by the 2009 Mw 6.3 L’Aquila event and by its foreshocks and aftershocks together with some additional events within our target region. For the mainshock, the source was represented by a finite fault and different models for central Italy, both 1D and 3D, were tested. Surface topography, attenuation and Moho discontinuity were also accounted for. Three-component synthetic waveforms were compared to the corresponding recorded data. The results of these analyses show that 3D models, including all the known structural heterogeneities in the region, are essential to accurately reproduce waveform propagation. They allow to capture features of the seismograms, mainly related to topography or to low wavespeed areas, and, combined with a finite fault model, result into a favorable match between data and synthetics for frequencies up to ~0.5 Hz. We also obtained peak ground velocity maps, that provide valuable information for seismic hazard assessment. The remaining differences between data and synthetics led us to take advantage of SEM combined with an adjoint method to iteratively improve the available 3D structure model for central Italy. A total of 63 events and 52 stations in the region were considered. We performed five iterations of the tomographic inversion, by calculating the misfit function gradient - necessary for the model update - from adjoint sensitivity kernels, constructed using only two simulations for each event. Our last updated model features a reduced traveltime misfit function and improved agreement between data and synthetics, although further iterations, as well as refined source solutions, are necessary to obtain a new reference 3D model for central Italy tomography.

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The aim of this work was to show that refined analyses of background, low magnitude seismicity allow to delineate the main active faults and to accurately estimate the directions of the regional tectonic stress that characterize the Southern Apennines (Italy), a structurally complex area with high seismic potential. Thanks the presence in the area of an integrated dense and wide dynamic network, was possible to analyzed an high quality microearthquake data-set consisting of 1312 events that occurred from August 2005 to April 2011 by integrating the data recorded at 42 seismic stations of various networks. The refined seismicity location and focal mechanisms well delineate a system of NW-SE striking normal faults along the Apenninic chain and an approximately E-W oriented, strike-slip fault, transversely cutting the belt. The seismicity along the chain does not occur on a single fault but in a volume, delimited by the faults activated during the 1980 Irpinia M 6.9 earthquake, on sub-parallel predominant normal faults. Results show that the recent low magnitude earthquakes belongs to the background seismicity and they are likely generated along the major fault segments activated during the most recent earthquakes, suggesting that they are still active today thirty years after the mainshock occurrences. In this sense, this study gives a new perspective to the application of the high quality records of low magnitude background seismicity for the identification and characterization of active fault systems. The analysis of the stress tensor inversion provides two equivalent models to explain the microearthquake generation along both the NW-SE striking normal faults and the E- W oriented fault with a dominant dextral strike-slip motion, but having different geological interpretations. We suggest that the NW-SE-striking Africa-Eurasia convergence acts in the background of all these structures, playing a primary and unifying role in the seismotectonics of the whole region.