Publications SISSA
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PubblicazioneInterplay Among Synaptic Glutamate Release and Excitotoxicity: Neuronal Damage and Graphene-Based Materials Related Protection( 2025)Glutamate-related excitotoxicity represents a fundamental pathological process underlying both acute and chronic disorders of the central nervous system. Excessive stimulation of ionotropic and metabotropic glutamate receptors induces ionic dysregulation, mitochondrial dysfunction, and oxidative stress, which can activate necrotic and apoptotic pathways, processes further amplified by defective glutamate clearance and astrocytic impairment. These mechanisms are recognized as key contributors to neuronal damage in ischemic stroke, Alzheimer’s disease, Parkinson’s disease, and Huntington’s disease, identifying excitotoxicity as a convergent hallmark of neurodegeneration. Despite considerable progress in elucidating its molecular mechanisms, clinical translation of excitotoxicity-targeted interventions remains limited, largely due to the difficulty of selectively attenuating pathological glutamatergic activity while preserving physiological neurotransmission. Recent advances in nanotechnology, particularly the development of graphene-based materials (GBMs), have offered innovative approaches for neuroprotection. Owing to their unique physicochemical properties and compatibility with neural tissue, GBMs have been investigated as platforms for neural interfacing, regenerative scaffolds, drug delivery platforms, and direct modulators of glutamatergic transmission. In particular, small graphene oxide nanosheets exhibit the capacity to downregulate glutamate release and confer anti-inflammatory and neuroprotective effects. These findings suggest that GBMs may represent a promising class of neuromodulatory tools for mitigating excitotoxic injury, warranting further preclinical and translational investigations.
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PubblicazioneMultiscale phenomena in quantum and classical models(SISSA, 2025-12-10)In this thesis we present several works dealing with multiscale phenomena. First, we treat a model of pattern formation: the Ising model with competing short-range and long-range interactions. We compute the energy asymptotic of excitations above the periodic ground states. In a second work we study a model of Quantum Hall Effect with a single edge-mode and subject to quasi-periodic disorder: through a combination of rigorous Renormalization Group techniques and \textsc{kam}-like estimates we compute the long distance asymptotic of all the correlations and use this asymptotic to in turn compute Kubo transport coefficients, as the condutivity, which turns to be quantized as expected. In the last work we consider a one-dimensional fermionic system again subject to quasi-periodic disorder, as a first step to treat two-dimensional systems with multiple edge-modes. We develop a new Renormalization Group scheme and report on progress in its applications.
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PubblicazioneMany-body physics of cavity embedded quantum matter(SISSA, 2025-12-03)Controlling the properties of quantum matter is a central goal of condensed matter physics. In recent years, cavity embedding—that is, shaping the electromagnetic environment surrounding a material by placing it inside a cavity—has emerged as a new potential tuning knob. While such concepts were first successfully explored with ultracold atomic clouds, more recent experiments have demonstrated their feasibility in solid-state systems. Despite the differences between these platforms, they share a key feature: the coexistence of degrees of freedom with distinct levels of locality. On one hand, electrons or atoms exhibit local dynamics (hopping, interactions), while on the other, cavity modes are typically delocalized across the entire system. The study of this unconventional quantum many-body framework—investigated through aspects such as phase transitions, topology, and dynamical properties—constitutes the main focus of this thesis.
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PubblicazioneCooperative mixing through hydrodynamic interactions in Stylonychia lemnae( 2025)Aquatic microorganisms typically inhabit a heterogeneous resource landscape, composed of localized and transient patches. To effectively exploit these resources, they have evolved a wide range of feeding strategies that combine chemotactic motility with active feeding flows. However, there is a notable lack of experimental studies that examine how these active flows shape resource fields to optimize feeding. In particular, the suspected cooperative hydrodynamics provided by groups of cells remains largely unexplored due to the difficulties in visualizing these dynamic three-dimensional flows. Here, we experimentally investigate how Stylonychia lemnae ciliates form feeding clusters of independent cells around food patches. Individual feeding flows interact hydrodynamically to create a chaotic collective flow at the population scale. Using a combination of experimental and numerical techniques, we measure and predict the entire collective flow, enabling us to assess its remarkable mixing and dispersion properties. We show that the active spreading of the food patch accelerates its detection by starving cells. As many fitness advantages provided by collective flows can be envisioned, we propose that this feeding cluster represents a form of intraspecific by-product cooperative behavior.
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PubblicazioneContinuum limit for discrete NLS with memory effect( 2025)We consider a discrete nonlinear Schrödinger equation with longrange interactions and a memory effect on the infinite lattice hZ with mesh-size h > 0. Such models are common in the study of charge and energy transport in biomolecules. Because the distance between base pairs is small, we consider the continuum limit: a sharp approximation of the system as h → 0. In this limit, we prove that solutions to this discrete equation converge strongly in L2 to the solution to a continuous NLS-type equation with a memory effect, and we compute the precise rate of convergence. In order to obtain these results, we generalize some recent ideas proposed by Hong and Yang in L2based spaces to classical functional settings in dispersive PDEs involving the smoothing effect and maximal function estimates, as originally introduced in the pioneering works of Kenig, Ponce and Vega. We believe that our approach may therefore be adapted to tackle continuum limits of more general dispersive equations.