86 research outputs found
Gambe gonfie in età pediatrica: un caso di “linfedema primario precoce”
No full textRiportiamo il caso di un bambino di 3 anni giunto alla nostra osservazione per la comparsa di un “gonfiore”
localizzato all’arto inferiore destro. L’anamnesi familiare e personale è risultata negativa per patologie di
rilievo o episodi analoghi e non veniva riferito alcun trauma nei giorni precedenti. La monolateralità e le
caratteristiche dell’edema con il supporto delle indagini di laboratorio e strumentali ci hanno fatto formulare la
diagnosi di “linfedema primario precoce”, una patologia rara in età pediatrica di cui riportiamo una breve
descrizione
Oltrepassare le barriere linguistiche attraverso un’attenta anamnesi con mediatore culturale per arrivare alla diagnosi corretta: un caso di inalazione di corpo estraneo
No full textDescriviamo il caso di una bambina marocchina di 2 anni che viene condotta in PSP perché presenta da alcune ore tosse e difficoltà respiratoria
Papillary thyroid cancer in thalassaemia.
No full textThyroid cancer is the most frequent endocrine neoplasm in the general population. Its incidence is 5-10/100,000 per year, with an annual death rate of 0.2-1.2/100,000 in men and 0.4-2.8/100,000 in women. In thalassaemia patients the frequency of this disease is unknown. In this paper we describe five cases of papillary thyroid cancer in thalassaemia patients followed at the Day Hospital for Thalassaemia and Haemoglobinopathies, in Ferrara, Italy. We consider the possible key role of iron as a carcinogenic agent and we also discuss the practical implications of our clinical observations
A hybrid BEM-CFD virtual blade model to predict interactions between tidal stream turbines under wave conditions
No full textTidal turbine array optimization is crucial for the further development of the marine sector. It has already been observed that tidal turbines within an array can be heavily affected by excessive aerodynamic interference, thus leading to performance deterioration. Small-scale experimental tests aimed at understanding the physical mechanisms of interaction and identifying optimal distances between machines can be found in the literature. However, often, the relatively narrow channels of laboratories imply high blockage ratios, which could affect the results, making them unreliable if extrapolated to full-scale cases. The main aim of this numerical study was to analyze the effects of the blockage caused by the laboratory channel walls in cases of current and also current surface waves. For this purpose, the performance predictions achieved for two turbines arranged in line for different lateral offsets in case of a typical laboratory scale were compared to the predictions obtained for a full scale, unconfined environment. The methodology consisted in the adoption a hybrid Blade Element Momentum–Computational Fluid Dynamics (BEM-CFD) approach, which was based on the Virtual Blade Model of ANSYS-Fluent. The results indicate that (1) the performance of a downstream turbine can increase up to 5% when this has a lateral separation of 1.5D from an upstream device in a full-scale environment compared to a misleading 15% calculated for the laboratory set-up, and (2) the relative fluctuations of power and thrust generated by waves are not significantly affected by the domain dimensions
A Calcified Mass in the Spinal Canal of a Patient With β-thalassemia Major
No full textA thirty-nine-year-old patient with β-thalassemia major had complained for 3 months of weakness in both legs, more marked proximally, reduced thermo-dolorific sensitivity bilaterally, and oedema of the feet and ankles. The symptoms worsened rapidly and within a month the patient was unable to walk. Mean pretransfusional hemoglobin in the past year was 8,5 g/dL. Due to severe and frequent episodes of atrial fibrillation the patient was on therapy with oral anticoagulants. Two years prior to the present episode, the patient underwent the evacuation of an intracranial subdural hematoma in the left fronto-parietal area. An unenhanced thoraco-lumbar Computed Tomography (CT) scan showed a well-circumscribed, oval, homogeneously hyperdense extramedullary mass lesion within the vertebral canal at D4-D5 level associated with a spinal cord compression (Figure). Magnetic Resonance Imaging (MRI) could not be performed because the patient carried a cardiac pace-maker. A scintigraphy with Tc99 marked red blood cells did not demonstrate the presence of functioning extramedullary erythropoietic tissue. The rapid progression of symptoms required a therapeutic laminectomy that evidenced a brownish, crumbly extramedullary mass that was completely removed. The post operative course was uneventful and the patient’s neurological symptoms slowly regressed
La nuova disciplina europea della responsabilità per danno da prodotti difettosi (dir. 2024/2853/UE)
No full textDirective 2024/2853/EU is largely inspired by the previous regime. The main differences lie in the updating of the provisions on digital products and on the introduction of new evidentiary facilitations. Overall, the new provisions, which the Author reviews, are equipped with a more analytical approach
WHY A THEORY OF SOCIETY CANNOT BE FOUNDED ON A THEORY OF ACTION: ON THE LEGACY OF SCIENTIFIC PROGRAMME SIXTY YEARS AFTER "THE STRUCTURE"
No full textAfter an examination of Parsons's theory of social action, the author demonstrate that sociology need to pass over to a new paradigm. This because Parsons' theory of general system of action shows that a theory of society cannot be based on a theory of action. It is investigate the possibility of finding grounds for a theory of society not based on a concept of action, as has already been suggested by a theory of social autopoietic systems by Niklas Luhmann
Hybrid BEM-CFD Virtual Blade Model to investigate the interaction between two marine turbines under tidal current and wave conditions
No full textIl Virtual Blade Model (VBM) è un modello ibrido BEM-CFD per lo studio di turbine ad asse orizzontale, che permette l’implementazione della teoria dell’elemento di pala (BEM) nel software di calcolo numerico ANSYS Fluent, tramite il caricamento di una User-Defined-Function. L’effetto della turbina viene simulato introducendo termini di sorgente, calcolati secondo la teoria BEM, nel bilancio della quantità di moto nella sola zona interessata dalla rotazione delle pale. Questo metodo permette un notevole risparmio sui tempi di calcolo in paragone con il CFD tradizionale, assicurando comunque risultati affidabili. La prima parte del presente lavoro di tesi consiste nella validazione del Virtual Blade Model in termini di predizione della performance di una turbina marina ad asse orizzontale e della scia da essa generata, mediante il confronto con misurazioni sperimentali in scala di laboratorio. Nella seconda parte della tesi il modello è stato utilizzato per studiare l’interazione tra due turbine idrocinetiche ad asse orizzontale in scala di laboratorio; in particolare si sono analizzati gli effetti della scia generata da una turbina a monte su una turbina posizionata a valle di essa, in linea o con un certo offset laterale, in condizioni di sola corrente e in condizioni combinate di onde e corrente. Queste simulazioni sono state infine ripetute in scala reale, in condizioni naturali marine non confinate, per valutare gli effetti di scala e di bloccaggio.
The Virtual Blade Model (VBM) is a hybrid BEM-CFD model for the study of horizontal axis turbines, which allows the implementation of the Blade Element Momentum (BEM) theory in the numerical calculation software ANSYS Fluent, by loading an User-Defined-Function. The turbine effect is simulated by introducing source terms, calculated according to the BEM theory, in the momentum balance only in the area affected by the rotation of the blades. This method allows a significant saving on calculation times in comparison with the traditional CFD, still ensuring reliable results. The first part of this thesis work consists in the validation of the Virtual Blade Model in terms of predicting the performance of a horizontal axis tidal turbine and the wake generated by it, through comparison with laboratory scale experimental measurements. In the second part of the thesis, the model has been used to study the interaction between two horizontal axis hydrokinetic turbines on a laboratory scale; in particular have been analysed the effects of the wake generated by an upstream turbine on a turbine positioned downstream of it, in-line or with a certain lateral offset, in conditions of current only and in combined conditions of waves and current. These simulations were finally repeated in full-scale unconfined natural marine conditions, to evaluate the scale and blockage effects
THE STATUE OF SAINT JEROME BY NICOLO Dl GIOVANNI FROM FLORENCE IN TROGIR
No full textAnalizom morfoloških kvaliteta i ikonografske karakterizacije renesansnog kipa Sv. Jeronima u Trogiru, autor poriče dosadašnje atribucije A. Alešiju i pripisuje ga čvršće Nikoli Firentincu. Dokazuje da je u kapelu Bl. Ivana unesen naknadno uz manje preinake, te slijedom povijesnih zapisa otkriva mu nastanak pri uređenju stare crkve sv. Marije na gradskome trgu zauzimanjem istog umjetnika prije godine 1480.In the Renaissance chapel of the blessed John of Trogir dating from the last quarter of the fifteenth century the statue of Saint Jerome has been placed, along with the figures of the twelve apostles, in one of the niches of the middle zone. In numerous studies this figure has been attributed to Andrea Alexius, the sculptor who was commissioned to work on the decoration of the chapel with Nicolo di Giovanni in 1468. After a detailed analysis of the morphology and expressiveness of the statue of Saint Jerome, in this text attrubuted it is to Nicola. In the statue the author recognizes the work of an artist who learned his craft in Italy. Owing to its iconology the author relates it to other statues of holy hermits found in Trogir and attributes them to Nicolo, although former critics tended to attrlbute them to Alexius. He also points out that the size of the base and lower part of the statue was subsequently reduced in order to fit it into a narrower niche which was evidently not its first location. Studying historical documents the author discovers that the small church of the Assumption of Mary situated just across the cathedral had previously had an altar with a statue of Saint Jerome. In that very church Nicolo di Giovanni added in 1476 an altar of Saint Sebastian with a fine sculpture of this saint. Comparing these two statues the author concludes that they both belong to the first phase of Nicolo's activity in Trogir, also drawing attention to their painted models (sketches). This leads to an entirely new evaluation of a notable sculpture and throws new light on the relation of two famous artists of Renaissance Dalmatia
Intelligent Systems for the Exploration of Structured and Complex Environments
No full textL’attività di ricerca si è concentrata sullo studio, progettazione e realizzazione di sistemi di raccolta dati in ambienti strutturati e complessi. Si è iniziato studiando metodologie e sensori tipicamente utilizzati negli ambienti strutturati, in particolare quello industriale, per poi procedere sull’ambiente sottomarino (ambiente complesso).
Tre sistemi meccatronici innovativi sono stati realizzati. Partendo da un ambiente strutturato è stata sviluppata una stazione automatica per il collaudo dei boiler domestici installata al termine di una catena produttiva. In questo caso studio si è contribuito allo sviluppo e implementazione di tecniche di image processing per l’identificazione dei difetti. La macchina in questo momento lavora autonomamente presso un importante azienda italiana e nelle varie sessioni ha una percentuale di individuazione dei difetti superiore al 90\%, con solo il 3\% di falsi positivi: percentuali di gran lunga migliori a quelle ottenute dagli operatori esperti dell’azienda.
Considerando l’ambiente sottomarino è stato progettato e sviluppato un dispositivo capace di collezionare dati per subacquei al fine di aiutare gli archeologi nell’esplorazione di siti archeologici e ricostruzione 3D. La sfida più importante nello sviluppo è stata implementare l’Unscented Kalman Filter (UKF) risolvente il problema della localizzazione fondendo i dati forniti da Ultra Short Baseline (USBL), Unità di Misura Inerziale (IMU) e ricevitore GPS. Proseguendo nella tematica di raccolta dati in ambienti non strutturati è stato sviluppato un veicolo marino pesciforme autonomo a propulsione ibrida. È stato caratterizzato il sistema di visione del veicolo basato su action camera ed il sistema di controllo dell’orientamento. Il controllore realizzato (Backstepping con osservatore non lineare del disturbo) ha permesso, tramite due motori brushless, la cancellazione del comportamento oscillatorio introdotto dalla propulsione biomimetica.Robotics is related with the development of robotic systems able to move knowing the environment where they must act. The environments diversities have brought researchers developing indoor and outdoor robotic techniques and technologies able to perceive movements and effects at the time arise. This work investigated possible design and implementation of mechatronic structures, able to work in industrial or complex unstructured environments.
As first aspect structured environment and needed sensors has been investigated. The work has been then expanded adding complexity to the aims and reducing the structures faced. During the work, three innovative mechatronic systems have been investigated. The first one regarded the highly structured industrial environment in which an intelligent and semi-autonomous station for testing domestic boilers during the production has been studied.
Considering a more challenging, not structured environment, where optical data need to be gathered with poses information, the author concentrated then on the underwater seabed reconstruction by means of photo cameras carried by divers. The most important challenge in the development of the designed platforms was the Unscented Kalman Filter (UKF) implementation to solve the navigation problem that fuses the data provided by an Ultra Short Baseline (USBL), an Inertial Measurement Unit (IMU) and a receiver for global positioning (GPS).
The work, after considering structured environment reconstruction by means of vision advanced techniques and after facing the situations without positioning structures in the environment, closed with the study of a situation where the robot movement alter the pose but in a way that can be estimated and prevented. An innovative Backstepping controller with a non-linear disturbance observer (NDO) has been designed for the hybrid actuation of the underwater robot under analysis reducing the oscillatory behavior introduced by the biomimetic propulsion
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