499 research outputs found

    MRI-guided focused ultrasound surgery in musculoskeletal diseases: the hot topics

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    MRI-guided focused ultrasound surgery (MRgFUS) is a minimally invasive treatment guided by the most sophisticated imaging tool available in today's clinical practice. Both the imaging and therapeutic sides of the equipment are based on non-ionizing energy. This technique is a very promising option as potential treatment for several pathologies, including musculoskeletal (MSK) disorders. Apart from clinical applications, MRgFUS technology is the result of long, heavy and cumulative efforts exploring the effects of ultrasound on biological tissues and function, the generation of focused ultrasound and treatment monitoring by MRI. The aim of this article is to give an updated overview on a "new" interventional technique and on its applications for MSK and allied sciences

    Dolori e trionfi di Rinaldo imperatore nel poema “Trabisonda” e nell’Opera dei Pupi siciliana

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    Rinaldo esule e imperatore in Oriente costituisce la materia del poema quattrocen-tesco intitolato Trabisonda. Queste vicende furono poi inserite da Giusto Lodico nella Storia dei Paladini di Francia, narrazione in prosa in cui egli riunì le trame di molti poemi carolingi che diventò la diretta fonte d’ispirazione per l’Opera dei Pupi. Le avventure di Rinaldo imperatore, comenarrate nel poema e come poi riplasmate nella Storia dei Paladini e dai pupari, costituiscono un esempio delle trasformazioni di significato che le vicende della letteratura cavalleresca hanno subito nel tempo in relazione ai contesti di fruizione. Nel Quattrocento, quando l’Occidente cristiano avvertiva la minaccia ottomana, si vedrà come le vicende di Rinaldo abbiano rivestito sia una funzione polemica che propagandistica. Molti secoli dopo, nella Sicilia dei secoli XIX e XX, vedremo invece come i fatti di Rinaldo imperatore rappresentassero l’acme di quell’aspirazione al ristabilirsi di un ordine del mondo più giusto che Antonino Buttitta e AntonioPasqualino hanno individuato come le ragioni profonde del successo delle storie paladinesche per i ceti subalterni siciliani in era preconsumistica. Rinaldo, in Occidente umiliato e disprezzato da Carlo Magno e Gano e glorificato in Oriente dai saraceni, diventava l’esempio tangibile del fatto che qualche volta al mondo le cose si rimettessero a posto e anche un modello di mobilità sociale che spingesse a considerare la stringente necessità di emigrare per lavoro come una reale possibilità di riscatto dalla miseria

    Full Scale Reinforced Concrete Beam-Column Joints Strengthened with Steel Reinforced Polymer Systems

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    This paper presents the results of an experimental campaign performed at the Laboratory of Materials and Structural Testing of the University of Salerno (Italy) in order to investigate the seismic performance of reinforced concrete (RC) beam-column joints strengthened with steel reinforced polymer (SRP) systems. With the aim to represent typical façade frames' beam-column subassemblies found in existing RC buildings, specimens were provided with two short beam stubs orthogonal to the main beam and were designed with inadequate seismic details. Five members were strengthened by using two different SRP layouts while the remaining ones were used as benchmarks. Once damaged, two specimens were also repaired, retrofitted with SRP, and subjected to cyclic test again. The results of cyclic tests performed on SRP strengthened joints are examined through a comparison with the outcomes of the previous experimental program including companion specimens not provided with transverse beam stubs and strengthened by carbon fiber-reinforced polymer (CFRP) systems. In particular, both qualitative and quantitative considerations about the influence of the confining effect provided by the secondary beams on the joint response, the suitability of all the adopted strengthening solutions (SRP/CFRP systems), the performances and the failure modes experienced in the several cases studied are provided

    Quantitative models of hydrothermal fluid–mineral reaction:The Ischia case

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    The intricate pathways of fluid–mineral reactions occurring underneath active hydrothermal systems are explored in this study by applying reaction path modelling to the Ischia case study. Ischia Island, in Southern Italy, hosts a well-developed and structurally complex hydrothermal system which, because of its heterogeneity in chemical and physical properties, is an ideal test sites for evaluating potentialities/limitations of quantitative geochemical models of hydrothermal reactions. We used the EQ3/6 software package, version 7.2b, to model reaction of infiltrating waters (mixtures of meteoric water and seawater in variable proportions) with Ischia’s reservoir rocks (the Mount Epomeo Green Tuff units; MEGT). The mineral assemblage and composition of such MEGT units were initially characterised by ad hoc designed optical microscopy and electron microprobe analysis, showing that phenocrysts (dominantly alkali–feldspars and plagioclase) are set in a pervasively altered (with abundant clay minerals and zeolites) groundmass. Reaction of infiltrating waters with MEGT minerals was simulated over a range of realistic (for Ischia) temperatures (95–260° C) and CO2 fugacities (10 ^-0.2 to 10^0.5) bar. During the model runs, a set of secondary minerals (selected based on independent information from alteration minerals’ studies) was allowed to precipitate from model solutions, when saturation was achieved. The compositional evolution of model solutions obtained in the 95–260°C runs were finally compared with compositions of Ischia’s thermal groundwaters, demonstrating an overall agreement. Our simulations, in particular, well reproduce the Mg-depleting maturation path of hydrothermal solutions, and have end-of-run model solutions whose Na–K–Mg compositions well reflect attainment of full-equilibrium conditions at run temperature. High-temperature (180–260° C) model runs are those best matching the Na–K–Mg compositions of Ischia’s most chemically mature water samples, supporting quenching of deep-reservoir conditions for these surface manifestations; whilst Fe, SiO2 and, to a lesser extent, SO4 contents of natural samples are better reproduced in low-temperature (95°C) runs, suggesting that these species reflect conditions of water–rock interaction in the shallow hydrothermal environment. The ability of model runs to reproduce the compositional features of Ischia’s thermal manifestations, demonstrated here, adds supplementary confidence on reaction path modelling as a realistic and insightful representation of mineral–fluid hydrothermal reactions. Our results, in particular, demonstrate the significant impact of host rock minerals’ assemblage in governing the paths and trends of hydrothermal fluids’ maturation

    Numerical modelling of gas-water-rock interactions in volcanic-hydrothermal environment: the Ischia Island (Southern Italy) case study.

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    Hydrothermal systems hosted within active volcanic systems represent an excellent opportunity to investigate the interactions between aquifer rocks, infiltrating waters and deep-rising magmatic fluids, and thus allow deriving information on the activity state of dormant volcanoes. From a thermodynamic perspective, gas-water-rock interaction processes are normally far from equilibrium, but can be represented by an array of chemical reactions, in which irreversible mass transfer occurs from host rock minerals to leaching solutions, and then to secondary hydrothermal minerals. While initially developed to investigate interactions in near-surface groundwater environments, the reaction path modeling approach of Helgeson and co-workers can also be applied to quantitative investigation of reactions in high T-P environments. Ischia volcano, being the site of diffuse hydrothermal circulation, is an ideal place where to test the application of reaction-path modeling. Since its last eruption in 1302 AD, Ischia has shown a variety of hydrothermal features, including fumarolic emissions, diffuse soil degassing and hot waters discharges. These are the superficial manifestation of an intense hydrothermal circulation at depth. A recent work has shown the existence of several superposed aquifers; the shallowest (near to boiling) feeds the numerous surface thermal discharges, and is recharged by both superficial waters and deeper and hotter (150-260° C) hydrothermal reservoir fluids. Here, we use reaction path modelling (performed by using the code EQ3/6) to quantitatively constrain the compositional evolution of Ischia thermal fluids during their hydrothermal flow. Simulations suggest that compositions of Ischia groundwaters are buffered by interactions between reservoir rocks and recharge waters (meteoric fluids variably mixed - from 2 to 80% - with seawater) at shallow aquifer conditions. A CO2 rich gaseous phase is also involved in the interaction processes (fCO2 = 0.4-0.6 bar). Overall, our model calculations satisfactorily reproduce the main chemical features of Ischia groundwaters. In the model runs, attainment of partial to complete equilibrium with albite and K-feldspar fixes the Na/K ratios of the model solutions at values closely matching those of natural samples. Precipitation of secondary phases, mainly clay minerals (smectite and saponite) and zeolites (clinoptilolite), during the reaction path is able to well explain the large Mg-depletions which characterise Ischia thermal groundwaters; while pyrite and troilite are shown to control sulphur abundance in aqueous solutions. SiO2(aq) contents in model simulations fit those measured in groundwaters and are being buffered by the formation of quartz polymorphs and Si-bearing minerals. Finally, our simulations are able to reproduce redox conditions and Fe-depletion trends of natural samples. We conclude that reaction path modelling is an useful tool for quantitative exploration of chemical process within volcano-hosted hydrothermal systems

    Structural Identification from Operational Modal Analysis: The Case of Steel Structures

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    In the case of old existing structures where the cultural value is very high, structural health analyses and investigations would be better performed without damages or service interruptions. Thus, modal analysis aimed at identifying eigenfrequencies and eigenmodes represents a very effective strategy to identify structural characteristics. In this paper, an innovative strategy to identify structural parameters exploiting the modal information obtained from operational modal analysis is proposed. The importance of the structural modeling in the problem formulation is highlighted. In the case of a simply supported beam, it was possible to assess the beam steel elastic modulus, while in the case of a cantilever beam, some constraint characteristics have been evaluated as well. In the steel frame case, the focus was on the constraint conditions of the structure determining the flexural stiffness of the springs representing the column base constraints. The method performances are promising for applications in larger structures such as bridges and buildings

    A spatial analysis model to assess the feasibility of short rotation forestry fertigated with urban wastewater: Basilicata region case study

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    The large-scale cultivation of energy crops irrigated with non-conventional water resources could reduce the negative impacts of fossil fuel use, while still saving potable supplies and decreasing pollution in surface water, particularly in water-deficient environments, like the Mediterranean region. Energy planning is a complex process involving multiple decision makers and criteria. Given the spatial nature of the problem, the research proposes a spatial analysis model to assess the agronomic and economic feasibility of vegetation filter systems in Basilicata region, southern Italy. The model chosen for land suitability analysis is the ordered weighted averaging (OWA) with the use of linguistic quantifiers. The suitability map obtained from the OWA model was used as input in the spatial analysis functions to quantify the productivity and irrigation needs of the species, the potential irrigable service area of the wastewater treatment plants (WWTPs), as well as the distances between them and SRF, which are all key elements in the economic evaluation. The results show that the distance is the main element that influences the feasibility: only 25 out of 163 WWTPs are cost-effective and can actually irrigate 864 ha of SRF. The research demonstrates that there is a great potential for bio-energy development in the region with significant economic advantages; in fact, there is a large number of sites with positive NPV up to 50,876.43 €/ha and payback period between 3 and 10 years. The implementation of vegetation filter systems could create chains with a high number of local actors (farmers, intermediaries, forest nurseries, etc.) and contribute to promoting territorial development and employment

    Healthcare Associated Infections. educational intervention by "Adult Learning" in an Italian teaching hospital

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    An educational intervention for HAI prevention based on a combination of training, motivation and subsequent application in the current clinical practice in an Italian teaching hospital

    A tool for evaluating geothermal power exploitability and its application to Ischia, Southern Italy

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    The paper proposes a method to evaluate the potential for electric power production at any site of possible geothermal interest. Accounting for geological data of the reservoirs, the method allows the computation of the available electrical power of the investigated site. Electrical energy production from geothermal sources is realized through different techniques, such as single flash and double flash, dry steam, and binary ORC plants. The technique chosen to be the most productive is determined by analyzing a specific range of geofluid properties, mainly temperature and pressure. Moreover, each plant typology has a global efficiency that may be correlated to geofluid enthalpy by empiric relations available in literature. The proposed evaluation method brings together all these correlations, yielding the power availability from a geosource, once its temperature and pressure are known. The method takes as input the geofluid available flow rate, its pressure, temperature and non-condensable gas content. It defines the best plant option from these parameters, calculates its global efficiency and finally returns the actual available power. For sites of geothermic interest, such as the volcanic island of Ischia in Southern Italy, the results of the application of this new method clearly highlight the most suitable zones for power plants installations
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