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PubblicazioneA Variational Approach to the Stability in the Homogenization of Some Hamilton–Jacobi Equations( 2026)We investigate the stability with respect to homogenization of classes of integrals arising in the control-theoretic interpretation of some Hamilton--Jacobi equations. The prototypical case is the homogenization of energies with a Lagrangian consisting of the sum of a kinetic term and a highly oscillatory potential V = Vper + W, where Vper is periodic and W is a nonnegative perturbation thereof. We assume that W has zero average in tubular domains oriented along a dense set of directions. Stability then holds true; that is, the resulting homogenized functional is identical to that for W = 0. We consider various extensions of this case. As a consequence of our results, we obtain stability for the homogenization of some steady-state and time-dependent, first-order Hamilton--Jacobi equations with convex Hamiltonians and perturbed periodic potentials. Finally, we show with an example that, for negative W, stability may not hold. Our study revisits and, depending on the different assumptions, complements results obtained by P.-L. Lions, P. Souganidis, and their collaborators using PDE techniques.
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PubblicazioneMany-body perturbation theory calculations using the yambo code( 2019)yambo is an open source project aimed at studying excited state properties of condensed matter systems from first principles using many-body methods. As input, yambo requires ground state electronic structure data as computed by density functional theory codes such as Quantum ESPRESSO and Abinit. yambo's capabilities include the calculation of linear response quantities (both independent-particle and including electron-hole interactions), quasi-particle corrections based on the GW formalism, optical absorption, and other spectroscopic quantities. Here we describe recent developments ranging from the inclusion of important but oft-neglected physical effects such as electron-phonon interactions to the implementation of a real-time propagation scheme for simulating linear and non-linear optical properties. Improvements to numerical algorithms and the user interface are outlined. Particular emphasis is given to the new and efficient parallel structure that makes it possible to exploit modern high performance computing architectures. Finally, we demonstrate the possibility to automate workflows by interfacing with the yambopy and AiiDA software tools.
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PubblicazioneA hybrid reduced-order model for segregated fluid-structure interaction solvers in an ALE approach at high Reynolds number( 2025)This study introduces a first step for constructing a hybrid reduced-order models (ROMs) for segregated fluid-structure interaction in an Arbitrary Lagrangian-Eulerian (ALE) approach at a high Reynolds number using the Finite Volume Method (FVM). The ROM is driven by proper orthogonal decomposition (POD) with hybrid techniques that combines the classical Galerkin projection and two data-driven methods (radial basis networks, and neural networks/ long short term memory). Results demonstrate the ROM's ability to accurately capture the physics of fluid-structure interaction phenomena. This approach is validated through a case study focusing on flow-induced vibration (FIV) of a pitch-plunge airfoil at a high Reynolds number (Re=107).
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PubblicazioneThe Influence of AHDC1 on the Output of Transcriptional Programs(SISSA, 2026-05-22)Xia-Gibbs syndrome (XGS) is a rare neurodevelopmental disorder caused by pathogenic variants in AHDC1. However, the cellular and molecular functions of AHDC1 remain poorly defined. In this thesis, I investigated AHDC1 function by combining RNA silencing in a controlled steady-state neuronal-like model with reanalysis of AHDC1-mutant differentiation datasets. In SH-SY5Y cells, AHDC1 silencing activated ribosome-related transcriptional programs, increased MYCN expression, and was associated with a global increase in protein abundance. Chromatin analysis using the T2T-CHM13 human reference genome showed no evidence of HP1 redistribution after AHDC1 silencing across canonical constitutive heterochromatin. Instead, the strongest differences were detected in the Input signal, indicating that AHDC1 silencing affects chromatin-associated signals without causing a change in HP1 targeting. Increased signals over ribosomal protein genes and rDNA clusters further pointed to ribosome-linked chromatin compartments as sensitive to AHDC1 silencing. To assess whether the same pattern emerges during differentiation, I reanalyzed a published AHDC1-mutant differentiation dataset. Reanalysis of ATAC-seq at day 7 after induction of differentiation revealed an increase in chromatin accessibility at rDNA clusters in mutant cell lines. Crucially, single-cell RNA sequencing demonstrated an altered lineage composition and a temporal uncoupling of biosynthetic programs: early progenitor stages exhibited MYC upregulation without a coordinated induction of ribosomal genes, whereas later committed stages displayed lineage-dependent persistence of MYC and increase in ribosome-related programs. Together, these findings support a model in which AHDC1 influences biosynthetic transcriptional programs. Rather than acting as a canonical locus-specific repressor, AHDC1 appears to influence broader genome regulation, with impact at ribosome-linked and nucleolus-associated compartments.
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PubblicazioneThe quantum Mpemba effect in closed systems: from theory to experiment( 2026)The Mpemba effect refers to a counterintuitive phenomenon whereby a system initially prepared further from equilibrium may relax faster than one prepared closer to equilibrium. While extensively studied in classical nonequilibrium physics, its extension to isolated quantum systems only started in the last few years. In this contribution we review recent progress on the quantum Mpemba effect in closed many-body systems, emphasizing the role of reduced density matrix, entanglement and symmetry restoration. We discuss why and how the entanglement asymmetry provides a natural and experimentally accessible framework to characterize Mpemba-like behavior in unitary quantum evolution.