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Hyperbolic Deep Learning System for Intelligent Gate-Driving and Health Monitoring of Silicon-Carbide Power MOSFETs
No full textAccurate monitoring of the gate–oxide health of Silicon-Carbide (SiC) MOSFET devices is pivotal for condition-based maintenance of electrified vehicles, high-frequency converters and consumer electronic applications. A MOSFET parameter closely related to the device oxide interface is the threshold voltage. The SiC MOSFETs threshold voltage (Vth) drifts with interface oxide–trap accumulation and it is therefore a direct early-marker of the device degradation. The Vth drift monitoring is then significantly relevant in the mentioned application fields. This work proposes a non-intrusive, single-shot intelligent pipeline that infers Vth solely from an input data-snapshot of the steady-state MOSFET static behavior based on current-to-voltage I − V family curves sampled during routine gate driving. We introduce HyperDeep, a novel Hyperbolic Möbius Deep architecture that embeds each I − V input snapshot in the hyperbolic Poincaré ball, processes it through ad-hoc designed residual Möbius layers followed by hyperbolic self-attention blocks. An adaptive exponential Lipschitz regularization block compensates process-spread-induced statistical drift in SiC devices, preserving mapping stability across SiC MOSFET's wide threshold-voltage window. The proposed HyperDeep system was trained on large dataset that includes both synthetic and real data obtained through Dynamic Gate Stress (DGS) methodology applied to SiC MOSFET GEN3 devices delivered by STMicroelectronics. The proposed deep pipeline attains in average of 0.015 MSE (Mean Squared Error) in retrieving actual Vth, outperforming compared state-of-the-art architectures
Cryptococcosis in Pediatric Renal Transplant Recipients: Comparative Insights from Adult Cases
No full textEditoriale. Caregivers and Autonomous Artificial Agents
No full textThe issue of care at a time when artificial intelligence and increasingly sophisticated technology aspire to take the place of humans raises a whole series of ethical questions that need to be addressed to ensure that change does not lead to a worrying lack of attention towards patients
Low-Energy Phonon Dynamics in Ordered-Disordered Systems: from Correlated Electron Materials to Perspectives for Thermoelectric Applications
No full textThe global energy demand continues to rise rapidly, driven by population growth, industrialization, and urbanization. Since the Industrial Revolution, fossil fuels have been the predominant energy source enabling electricity generation, trans-portation, and industrial processes. However, their extensive use poses critical environmental challenges such as pollution, atmospheric degradation, global warming, and ozone depletion. Addressing these issues requires urgent global efforts to transition toward clean, renewable, and sustainable energy technolo-gies.
In this context, the exploration of novel materials capable of efficient energy con-version and transport has gained significant attention. Complex ordered-disordered systems have emerged as promising candidates for next-generation green energy applications due to their unique charge and phonon transport phe-nomena. Yet, the fundamental origins of these strongly correlated behaviours remain insufficiently understood, especially the roles played by low-frequency phonons, which are central to lattice dynamics and charge transport processes.
This thesis aims to deepen the fundamental understanding of phonon localiza-tion and softening mechanisms, which are pivotal in controlling charge and heat transport behaviours in advanced functional materials. Phonon localization, of-ten arising from lattice disorder and anharmonicity, suppresses the propagation of heat-carrying lattice vibrations, significantly influencing thermal conductivity. Phonon softening, marked by decreased phonon frequencies, indicates lattice in-stabilities driven by electron-phonon coupling, magnetic interactions, or struc-tural phase transitions. These vibrational phenomena profoundly affect the in-terplay between lattice dynamics and electronic states, modulating phenomena such as charge density wave (CDW) formation and transport properties in quan-tum materials. Charge transport is strongly impacted by phonon softening and localization through enhanced electron-phonon scattering and altered carrier mobility, which can induce unconventional electronic phases. For example, in transition metal dichalcogenides (TMDs), CDWs emerge through the condensa-tion of soft phonon modes, reflecting a delicate coupling between lattice vibra-tions and electronic charge modulations. Similarly, metal halide perovskites (MHPs), a class of materials characterized by phonon glass electron crystal (PGEC) behaviour, manifest crystalline electronic conduction coexisting with glass-like phonon transport, the latter governing by phonon localization and mode softening arising from strong lattice anharmonicity and dynamic disorder.
To investigate these intricate phenomena, this work combines advanced experi-mental and theoretical techniques: temperature- and polarization-dependent Raman spectroscopy, density functional theory (DFT) vibrational calculations, low-temperature specific heat, and low-temperature thermal conductivity meas-urements. These approaches enable a direct connection between microscopic phonon dynamics and macroscopic charge and heat transport properties.
The thesis is organized into two main sections reflecting different material sys-tems and their phonon-charge transport behaviour.
The first part explores CDWs in the TMD family, focusing on a 1T-TaSe2 sample. Through detailed Raman spectroscopy and complementary DFT analyses, this study elucidates the lattice dynamics and atomic displacements driving CDW transitions, offering insights into the coupling of electronic correlations and lat-tice instabilities. This work was undertaken in collaboration with researchers at the University of Bath and Politecnico di Milano, contributing to the publica-tion titled “Identification of Soft-Modes Across the Incommensurate-to-Commensurate Charge Density Waves Transition in 1T-TaSe2” (Physical Review B).
The second part of this thesis focuses on thermoelectric materials (TMs), which convert waste heat into electricity without moving parts or harmful by-products. Improving thermoelectric efficiency requires a combination of both high electri-cal conductivity and ultra-low lattice thermal conductivity, which are hallmarks of PGEC materials. My work centres on investigate MHPs, whose unique struc-tural features – such as loosely bonded atoms, bonding hierarchies, and elas-tically soft lattices – effectively suppress phonon transport while preserving crys-talline pathways for charge conduction. Through low-temperature specific heat and thermal conductivity measurements, complemented by temperature depend-ent Raman spectroscopy and DFT calculations, this research provides direct in-sight into how these structural and chemical traits give rise to phonon-glass be-haviour and influence thermal transport.
This integrated methodology establishes a clear connection between microscopic lattice vibrations and macroscopic transport properties, highlighting the pivotal role of low-frequency phonons in mediating lattice instabilities and heat conduc-tion.
This work further uncovers the microscopic origins of phonon softening and lo-calization, drive by lattice anharmonicity and dynamic disorder. To disentangle the interplay of structural and chemical factors, perovskites of different dimen-sionalities and chemical compositions have been systematically investigated. By exploring systems that span from three-dimensional to zero-dimensional struc-tures, this thesis systematically addresses how lattice softness, local bonding in-stabilities, and stereo-chemically active lone pairs contribute to the emergence of glass-like phonon behaviour in otherwise crystalline materials.
Ultimately, the findings demonstrate that phonon softening and localization in MHPs emerge from the interplay of anharmonic bonding interactions and the in-herent softness of the perovskite network. By bridging atomic-scale vibrational instabilities with the suppression of thermal conductivity, this thesis advances the microscopic understanding of transport phenomena in complex materials and provides guidance for the design of next-generation TMs and energy-related functional compounds.
This second part was undertaken in collaboration with Institute of Low Tempera-ture and Structural Research in Wroclaw (Poland), with great support of Dr. Ing. Daria Szewczyk, East China Normal University, Shanghai (China), with valuable contributions of Prof. Chen Jiangang and his team. The work was conducted within the framework of PRIN PNRR project “StopHEAT: Glass-like phonon transport in eco-friendly perovskites for thermoelectric energy generation” under the supervision of Prof. Giovanna D’Angelo
Towards Innovative Study of Cyrillic Alphabet through Contemporary Information Technologies. Challenges and New Perspectives
No full textBioengineering and elastodontic treatment with oral bio-activators in young children
No full textBackground. Elastodontic therapy can correct bad oral habits and malocclusions in young patients by guiding jaw growth, eliminating functional disorders, and improving tooth position.
Aim. To assess the effects of Bio-activator therapy on the presence of atypical swallowing with tongue thrust in growing patients. Materials and Methods. A retrospective study was conducted. Data regarding the early orthodontic treatment of 40 consecutive patients with atypical swallowing and tongue thrust (23 males and 17 females) were assembled from January 2019 to January 2020. All patients (≥7 and ≤15 years of age) were monitored for 1 year in a private practice in Isernia, Italy.
Results. The mean age at commencement of orthodontic treatment was 8.5 years (range = 7.1–14.9 years), and the mean total duration of therapy was 1 year (range = 11 months–1 year). Final lateral radiographs demonstrated a mean of improvement of 8° for upper and lower incisor proclination (I/SN) and 3.5° for incisor mandibular plane angle (IMPA) in 36 patients, and 5° of I/SN and 2° of IMPA in the remaining 4 children after 1 year of treatment.
Conclusions. Bad oral habits in younger patients must not be ignored. The duration of treatment can differ depending on the severity of the open bite and the patient’s cooperation. This study demonstrates the short-term efficacy of these myofunctional appliances in the treatment of atypical swallowing. In order to quickly eliminate factors which endanger healthy development of dento-skeletal structure, it is important to closely monitor patients during their development phase
Bortezomib-melphalan-prednisone versus lenalidomide-dexamethasone in elderly patients with multiple myeloma: the Real MM phase IV trial
No full text: Not available
Immunohistochemical ERG positivity is associated with decreased PSMA expression and lower visibility in corresponding [68Ga] Ga‐PSMA‐11 PET scans of primary prostate cancer
No full textInformazioni commerciali dirette ai minori d’età tra divieti e rimedi
No full textIl saggio tratta della protezione on line dei minori riguardo le informazioni pubblicitarie diffuse attraverso i nuovi canali di comunicazione. Al fine di garantire un elevato livello di tutela della vita privata, di sicurezza e di protezione all’interno del mercato digitale, l’art 28 del Digital services act vieta la profilazione dei dati dei soggetti minori ponendosi in continuità con la direttiva UE sui servizi audiovisivi. Il divieto di profilazione è, tuttavia, subordinato alla conoscenza “da parte delle piattaforme, con ragionevole certezza, che il destinatario sia un minore” e, pertanto, l’analisi si concentra sulle criticità legate all’accertamento dell’effettiva età degli utenti
Iperprotezione, autolimitazioni e blocchi interiorizzati
No full textL’articolo esamina le dinamiche dell’iperprotezione e del controllo eccessivo in ambito educativo e familiare, evidenziando le principali implicazioni che ne possono derivare sullo sviluppo dell’autonomia, dell’identità e delle capacità decisionali degli studenti. Dopo una assegna della terminologia internazionale, vengono descritte le principali manifestazioni dell’iperprotezione, sia nel rapporto genitore-figlio sia nella relazione docente-studente. Il contributo si sofferma inoltre sul processo di trasformazione dei limiti esterni in autolimitazioni interiorizzate e sul ruolo centrale dell’errore e della frustrazione nei percorsi di crescita. L’obiettivo del lavoro è fornire una base per comprendere i rischi di pratiche educative e orientative eccessivamente direttive e limitanti, promuovendo riflessioni e strategie utili per ambienti di apprendimento equilibrati, stimolanti e
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