University of Modena and Reggio Emilia
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Romanian DOM and Loss of Analyzability
No full textThis paper revisits the diachronic changes to Romanian DOM by focusing on the emergence of the DOM particle pe: the prenominal preposition pe is shown to undergo loss of analyzability when (i) the adjacent noun phrase is the direct object of the verb; and (ii) pe-DP falls under a certain pragmatic treatment. In other contexts, pe continues as a preposition. Loss of analyzability entails modification of the feature bundle associated with pe, as well as chunking and sensitivity of pe-noun phrases to discourse related priming factors. Briefly, the chunk consisting of two segments (i.e., prepositional phrase and nominal phrase: PP > DP) is gradually reduced to one segment (i.e., DP). This transition is context dependent; that is, it intensifies when the DPs receive a reading that involves discourse salience and animacy. The loss of analyzability regarding the properties of pe and the structural consequences it implied provide the basis for assessing the advent of animacy and definiteness/specificity as priming factors for DOM in Modern Romanian
Synergistic Action of Short and Continuous Fibres in Mineral-Bonded Hybrid Protective Composites
No full textThe development of novel, cost-effective and highly-optimised construction materials to protect existing infrastructure against extreme loads in a sustainable and affordable way is crucial for the transformation of the construction sector. In this context, fibre and textile reinforced cement-based composites offer attractive solutions. Although Textile Reinforced Concrete (TRC) is emerging as a promising technology, the use of a brittle matrix still raises major concerns, particularly in terms of impact resistance in combination with fire. This paper investigates the mechanical behaviour of hybrid cementitious composites, in which high-tenacity textile plies are embedded in fibre-reinforced matrices with additional ductility resources. The tensile properties of such hybrid solutions are assessed by quasi-static testing. It is shown that short fibres lead to damage smearing by multiple cracking and optimal exploitation of the strength of the textile. More remarkably, this damage smearing plays a critical role under impact and blast scenarios by dissipating considerable amounts of mechanical energy and favouring the strengthening action of the textile, which underlies a promising application potential as an externally bonded protection for critical concrete members to enhance robustness and resilience. Some examples from recent research are presented to illustrate how fibres and textiles work synergistically in hybrid composites for structural protection
Comparison of Biometric Measurements Between IOL Master 700 and MS-39 in Post-LASIK Myopic Eyes: Implications for IOL Selection in Cataract Surgery
No full textStrutturazione del fascio elettronico con un piatto di fase regolabile
No full textLa strutturazione del fascio elettronico consente di controllare il fronte d’onda — in fase e ampiezza — per generare fasci strutturati e migliorare imaging, spettroscopia e correzione delle aberrazioni nella microscopia elettronica a trasmissione (TEM). Ciò è ottenuto tramite piatti di fase, che modulano la fase degli elettroni in piani specifici del microscopio. Tra le varie implementazioni (a film sottile, magnetiche, fotoniche e olografiche), i piatti di fase elettrostatici risultano particolarmente promettenti, poiché offrono un controllo di fase regolabile in tensione, a bassa perdita e con minimo materiale diffusivo nel cammino del fascio. Il loro funzionamento si basa sull’effetto Aharonov–Bohm: un elettrone acquisisce una fase proporzionale al potenziale elettrostatico attraversato, consentendo di modellare il fronte d’onda attraverso una distribuzione di potenziale progettata.
Le moderne piastre di fase elettrostatiche sono dispositivi MEMS su chip di silicio montati su portacampioni con contatti elettrici per TEM. Tuttavia, la progettazione è limitata da (i) pochi canali di biasing nei portacampioni commerciali, che riducono i profili di potenziale realizzabili, e (ii) difficoltà di fabbricazione di elettrodi complessi vicino alla regione attiva. Per superare questi limiti, questo lavoro introduce i Piatti di Fase Elettrostatici a Potenziale Controllato da Corrente, un concetto innovativo che genera gradienti di potenziale continui con architetture semplici e pochi canali. Gli elettrodi di bordo, in silicio drogato resistivo e collegati tramite strati d’oro ad alta conducibilità, creano una caduta di potenziale lineare applicando una corrente controllata, riproducendo gradienti complessi con un numero minimo di potenziali variabili indipendenti.
Questo approccio consente dispositivi compatti, sintonizzabili e riconfigurabili. Attraverso ottimizzazione basata su gradiente, sono stati progettati generatori di fasci a vortice, sorter di momento angolare orbitale (OAM) e multipoli elettrostatici (quadrupolo ed esapolo) per la compensazione delle aberrazioni. I piatti di fase esapolari mostrano rotazione di fase dipendente dal potenziale, consentendo l’allineamento di A3 a qualunque orientazione con un singolo dispositivo, un vantaggio rispetto ai correttori multipolari convenzionali che richiedono riallineamenti meccanici complessi. Le simulazioni elettrostatiche FEM e la propagazione ottica d’onda confermano i profili di fase desiderati, e il primi prototipi di chip MEMS sono stati fabbricati e caratterizzati con successo.
Parallelamente, è stata sviluppata una pipeline di ottimizzazione e controllo assistita da IA. Una rete neurale profonda (DNN) analizza un’unica immagine STEM focalizzata per stimare in millisecondi l’orientamento degli astigmatismi al secondo (A2) e terzo (A3). Integrata in un’interfaccia Python, la rete guida un ciclo di retroazione che regola i potenziali del piatto di fase tramite un controller PCB dedicato, consentendo la correzione automatica delle aberrazioni senza ricorrere a procedure Ronchigram o Zemlin.
In sintesi, questo lavoro dimostra che i piatti di fase elettrostatici controllati in corrente costituiscono una piattaforma compatta e a bassa perdita per il controllo programmabile del fronte d’onda in TEM. Combinando progettazione elettrostatica, ottimizzazione basata su IA e controllo mediante apprendimento automatico, apre la strada alla strutturazione del fascio elettronico e alla correzione in tempo reale delle aberrazioni nella microscopia elettronica di nuova generazione.Electron beam shaping enables control over the electron wavefront—its phase and amplitude—to generate structured beams and enhance imaging, spectroscopy, and aberration correction in transmission electron microscopy (TEM). This is achieved using phase plates, which modulate the phase of electrons at specific planes of the microscope. Among various implementations (thin-film, magnetic, photonic, and holographic), electrostatic phase plates are especially promising because they offer voltage-tunable, low-loss phase control with minimal scattering material in the beam path. Their operation relies on the Aharonov–Bohm effect: an electron acquires a phase proportional to the electrostatic potential it experiences, allowing a designed potential distribution to sculpt the beam wavefront.
Modern electrostatic phase plates are MEMS-based devices fabricated on silicon chips and mounted on biasing TEM holders. However, their design faces two main challenges: (i) limited numbers of biasing channels in commercial holders restrict the achievable potential profiles, and (ii) complex electrode geometries are difficult to fabricate near the active region. To overcome these limits, this work introduces Current-Controlled Electrostatic Potential Phase Plates, a novel concept that achieves continuous potential gradients using simple, low-channel architectures. In this design, boundary electrodes are fabricated from resistive doped silicon and connected through high-conductivity gold layers. By driving a controlled current along these electrodes, a linear potential drop is established, reproducing complex boundary gradients with minimal independent biases.
This approach enables compact, tunable, and reconfigurable devices. Using gradient-based optimization, we designed current-controlled vortex beam generators, orbital angular momentum (OAM) sorters, and electrostatic multipoles (quadrupole and hexapole) for aberration compensation. The hexapole phase plate demonstrates bias-driven phase rotation, allowing alignment to any A3 orientation with a single device—an advantage over conventional multipole correctors that require complex mechanical realignment. Finite-element electrostatic simulations and wave-optical propagation confirm the desired phase profiles, and prototype MEMS chips have been successfully fabricated and characterized.
To complement hardware development, we implemented an AI-assisted optimization and control pipeline. A deep neural network (DNN) analyzes a single focused STEM probe image to estimate the orientation of twofold (A2) and threefold (A3) astigmatism within milliseconds. Integrated into a Python-based graphical interface, the DNN drives a feedback loop that adjusts the phase-plate biases via a custom PCB controller, enabling automatic aberration correction without switching to conventional Ronchigram or Zemlin procedures.
The project’s main contributions include:
• Definition and demonstration of Current-Controlled Electrostatic Potential Phase Plates, reducing required bias channels while increasing design flexibility.
• Gradient-based optimization linking target phase maps to boundary potentials.
• MEMS fabrication and characterization of vortex, OAM-sorter, and hexapole phase plates.
• A DNN-based probe-shape method for real-time A2/A3 orientation estimation and automated feedback control.
In summary, this work establishes current-controlled electrostatic phase plates as a compact, low-loss platform for programmable wavefront control in TEM. Combining electrostatic design, AI-assisted optimization, and machine learning–based feedback, it opens a path toward adaptive beam shaping and real-time aberration correction for next-generation electron microscopy
Human Capital for the Knowledge Economy: Upskill Journeys in Advanced Capitalist Democracies
No full text
Numerical Assessment of Alternating Projection Methods for Matrix Completion with Application to Sparse Image Reconstruction
No full textIn this paper, we evaluate the numerical performance of the alternating projection method (APM) and a regularized variant of the same method (RAPM) for matrix completion. Both methods are based on the reformulation of matrix completion as a nonconvex feasibility problem. However, the regularized method shares global convergence guarantees even in the nonconvex setting, unlike its standard counterpart. Numerical experiments on randomly generated Gaussian matrices show that RAPM is much more robust with respect to the choice of the initial guess than APM is, as well as being insensitive to the regularization effect for a wide range of regularization parameters. Preliminary numerical results showing the effectiveness of RAPM on some sparse image reconstruction test problems are also presented
