The natural history of hypertrophic cardiomyopathy

In the early years of the disease recognition, hypertrophic cardiomyopathy (HCM) was viewed as an ominous disease with unfavourable prognosis and with an annual mortality between 4% and 6%. At that time, 73% of the patients reported in the literature came from only two referral centres. With the introduction of echocardiography, our understanding of HCM has improved and non-selected patient populations were assembled in several centres. A more benign prognostic profile was documented with an annual mortality rate of 1.5% or less. In the 2000s, important therapeutic interventions further improved the prognosis of patients with HCM: implantable-cardioverter defibrillator for prevention of sudden death, heart transplantation for treatment of severe refractory heart failure, and an extensive treatment with myectomy for relief of left ventricular outflow tract gradient. The natural history of HCM has changed substantially with contemporary treatment achieving an annual mortality rate less than 1% with extended longevity and a greatly improved quality of life

Pliocene crustal shortening on the Tyrrhenian side of the northern Apennines: evidence from the Gavorrano antiform (southern Tuscany, Italy)

The northern Tyrrhenian Sea and the inner northern Apennines are classically regarded as a late Miocene–Pleistocene back-arc system developed as a consequence of slab rollback along active subduction zones. We present new geological and structural data on the Gavorrano antiform, a key sector of the inner northern Apennines. Lying close to the northern Tyrrhenian Sea, it provides clear evidence of Pliocene shortening deformation and magma emplacement. The orientation of 1 (N50°E–N80°E) derived by fault slip data inversion is consistent with a general ENE–WSW shortening direction. Furthermore, this ENE–WSW-trending orientation of 1 is compatible with the compressive deformation recorded in coeval sedimentary basins. On this basis we suggest that the inner northern Apennines were affected by crustal shortening during the Pliocene. This scenario matches well geophysical data suggesting that since the Late Messinian (6–5 Ma) subduction rollback and back-arc extension strongly decreased in the northern Tyrrhenian Sea, whereas they continued as active processes in the southern Tyrrhenian Sea

Dead Time Management in GaN Based Three-Phase Motor Drives

This paper deals with the dead time selection in Gallium Nitride (GaN) FET based three-phase brushless DC motor drives. The GaN wide-bandgap (WBG) technology enables the increase of the switching frequency compared with silicon MOSFET. In inverter applications, it is necessary to insert a dead time in the switching signals, to avoid cross conduction in the inverter leg. The dead time selection is a compromise between the switching time and the quality of the inverter output waveforms. GaN FETs can operate with dead times in the range of tens of ns. In this paper the advantages of the GaN technology in the reduction of dead time in terms of output waveforms distortion and speed ripple compared with silicon MOSFET are carried out. Furthermore, an evaluation on the dead time compensation technique compared with the hardware technology reduction is investigated demonstrating the effectiveness and the saving of software and hardware resources obtained by GaN FET devices

Pliocene crustal shorthening on the Tyrrhenian side of the northern Apennones: evidence from the Gavorrano antiform (southern Tuscany, Italy)

The northern Tyrrhenian Sea and the inner northern Apennines are classically regarded as a late Miocene-Pleistocene back-arc system developed as a consequence of slab roll-back along active subduction zones. We present new geological and structural data on the Gavorrano antiform, a key sector of the inner northern Apennines. Lying close to the northern Tyrrhenian Sea, it provides clear evidence of Pliocene shortening deformation and magma emplacement. The orientation of σ1 (N50°E - N80°E) derived by fault slip data inversion is consistent with a general ENE –WSW shortening direction. Furthermore, this ENE-trending orientation of σ1 is compatible with the compressive deformation recorded in coeval sedimentary basins. On this basis we suggest that the inner northern Apennines were affected by crustal shortening during the Pliocene. This scenario matches well geophysical data suggesting that since the Late Messinian (6 – 5 Ma) subduction rollback and back-arc extension strongly decreased in the northern Tyrrhenian Sea, while they continued as active processes in the southern Tyrrhenian Sea

Geomorphological and geochemical characterization of the 11 August 2008 mud volcano eruption at S. Barbara village (Sicily, Italy) and its possible relationship with seismic activity

On 11 August 2008 a paroxysmal eruption occurred at Santa Barbara mud volcano (MV), located close to Caltanissetta, one of the most densely populated cities of Sicily (Italy). An associated minor event took place on August 2009. Both the events caused severe damage to civil infrastructures located within a range of about 2 km from the eruptive vent. Geomorphological, geochemical, and seismological investigations were carried out for framing the events in the appropriate geodynamic context. Geomorphological surveys recognized, in the immediate surrounding of the main emission point, two different families of processes and landforms: (i) ground deformations and (ii) changes in morphology and number of the fluid emitting vents. These processes were associated to a wider network of fractures, seemingly generated by the shock wave produced by the gas blast that occurred at the main paroxysm. Geochemical characterization allowed an estimation of the source of the fluids, or at least their last standing, at about 3 km depth. Finally, the close time relationships observed between anomalous increments of seismic activity and the two main paroxysmal events accounted for a possible common trigger for both the phenomena, even with different timing due to the very different initial conditions and characteristics of the two processes, i.e. seismogenesis and gas overloading

Monolithic Bidirectional Switch Based on GaN Gate Injection Transistors

The paper deals with a bi-directional switch based on N-channel enhancement-mode GaN FET. The proposed device is a Gate Injection Transistor monolithic solution to reduce the volume of the switch with high current density and blocking voltage of 600V. It features a dual-gate control pin and two power terminal. In the paper, the main characteristics of the bi-directional switch and the performance in the four-quadrant of operation are examined and discussed. The device characteristics are compared with the traditional MOSFET and IGBT solutions. The gate driver design issues are considered to optimize the switching transient of the GaN-based switch. Finally, an experimental evaluation of the GaN FET as the bidirectional circuit breaker is carried out in an AC power supply system to validate the effectiveness of the proposed monolithic new device

ARTIFICIAL INTELLIGENCE APPLIED TO THE STUDY OF CONSCIOUS PERCEPTIVE STATES

My PhD research consists of the processing of signals from a 14-electrode EEG system, connected to immersive glasses that allow for a realistic visual experience and for the investigation of the brain network in order to identify signal features corresponding to different perceptive and cognitive stimuli. The aim of the research is to implement a procedure that identifies correspondences among EEG signals and chaotic attractors. The chaotic attractors can be defined as a trajectory of a dynamical system, contained in a defined volume of phase space. A dynamical system can have chaotic behavior, i.e. an organized (but not periodic) behavior sensitive to the initial conditions. EEG signals can be considered dynamical systems. In this work a custom Artificial Neural Network (ITSOM) processes individual signals or many signals simultaneously. The sequence of the ITSOM winning nodes tends to repeat itself creating a time series of chaotic attractors. The ITSOM attributes similar codes to attractors emerging from similar brain states, perceptions and emotions. These attractors are isomorphic to the attractors in which the corresponding dynamical system (the signal time series) is evolving and univocally characterize the input element that produces them. If the attractors are chaotic, this means that the signals are individually self-organized or, by examining more signals together, there is a form of coherence among signals. The ITSOM network memorizes the time series of the winning nodes. The cumulative scores for each input are normalized following the z standardized variable distribution. Attractors are labeled with a binary code that univocally identifies them, and the flexibility of the Artificial Neural Network allows attributing the same codes to similar dynamical events. During the experiment, the subject is looking at the screen while different shades of colors, yellow, red and blue are displayed. Each stimulation lasts five seconds, between stimuli there is a black screen, used to reset the previous color stimuli. The collected results show, as forecast, many correspondences among binary codes coming from similar stimuli. The thesis provides a detailed description of these results