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la normalizzazione dell'inciviltà
No full textPerché la politica contemporanea sembra essere sempre più uno scontro senza esclusione di colpi? Perché la volgarità, l’aggressività verbale, la delegittimazione dell’avversario e la discriminazione dell’altro sono diventate pratiche comuni nella cronaca politica fino ad arrivare, talvolta, a premiare chi vi ricorre?
In un’epoca in cui la democrazia appare sotto pressione, La politica dello scontro indaga come e perché l’inciviltà sia diventata non un’eccezione, ma una componente strutturale del dibattito pubblico. A partire da una ricerca comparata in Italia, Germania e Regno Unito, il volume esamina l’inciviltà come attributo della politica attuale, analizzandone le molteplici manifestazioni e le diverse cornici interpretative: dalla percezione dei cittadini alla rappresentazione mediatica, dalle pratiche giornalistiche alle strategie comunicative dei politici, fino al ruolo delle piattaforme digitali e alla crescente mediatizzazione della sfera pubblica
Modelling phase change in multiphase flows
No full textSince childhood, we’ve been taught that at standard atmospheric pressure water boils at 100°C, but is that really the whole story? The formation of bubbles, as well as droplets, are phenomena we commonly observe in everyday life, think of raindrops falling from the sky or the bubbles rising to the surface of a boiling kettle. The ubiquity of these phenomena has led us to develop an overly simplistic view of the underlying processes.
The most frequent mechanisms driving the liquid–vapor phase transition is nucleation: when a liquid or vapor is under suitable thermodynamic conditions, corresponding to a metastable state, thermal fluctuations can induce the formation of clusters which, as they grow, lead to the formation of the new phase. Various factors can accelerate or hinder cluster formation, thereby influencing the boiling and condensation temperatures of a fluid. These factors include the fluid’s
thermodynamic properties, the presence of dissolved species and impurities, surface characteristics of solid walls such as wettability and nanoscale roughness, and the presence of heat and mass fluxes. Experiments have shown that pure water, in the absence of container effects, can boil at 302°C under atmospheric pressure, highlighting the gap between our common understanding of the phenomenon and the physics governing the process.
The purpose of this study is to investigate some open questions related to the nucleation mechanism: under which thermodynamic conditions does nucleation become likely? What is the most probable sequence of events leading to bubble or droplet formation? How do dynamical effects influence the nucleation pathway and its probability? Can simplified models capture the key features? Do solid walls or heat/mass fluxes enhance or suppress the phenomenon?
To shed some light on these questions, a continuum model that bridges atomistic simulations and continuum mechanics, seeking to combine the predictive power of the former with the computational efficiency of the latter, will be presented in this work. Nucleation is an inherently multiscale phenomenon: bubbles and droplets form at nanoscales within nanoseconds, but are observed experimentally across micrometer to millimeter scales and over time windows of seconds.
For this reason, the choice of a mesoscale model is the most natural one. Specifically, it will be shown how a diffuse interface model, combined with multiparametric equations of state, is able to
provide a qualitative and quantitative description of the liquid-vapor phase transition. To identify the most probable nucleation pathway and provide a method to efficiently compute it, the mathematical framework of large deviation theory, together with rare event techniques, has been employed. This study will reveal how dynamical effects, often neglected in classical models, play a fundamental role by altering both the nucleation pathway and the transition probability. Nevertheless, we will demonstrate how simplified models that capture the salient features of the process can be constructed through an effective description of the system. Finally, coupling this diffuse interface model with fluctuating hydrodynamics enables the investigation of intrinsically out-of-equilibrium systems, where thermal and mass fluxes, together with the wettability of solid walls, critically influence the onset and pathway of nucleation
Enhancing copper processability via carbon nanotubes reinforcement in Powder Bed Fusion - Laser Based. Dragon Copper
No full textPowder Bed Fusion - Laser Based (PBF-LB) is a widely used additive manufacturing technology for metallic materials, but its application to pure copper remains challenging due to its high reflectivity in the near-infrared (NIR) wavelength range, commonly employed in commercial laser systems. This paper proposes a strategy to overcome this limitation by incorporating carbon nanotubes (CNTs) into the powder bed, enabling the PBF-LB manufacturing of pure copper while simultaneously enhancing its functional properties, as demonstrated through multiscale characterization performed at both powder and manufactured level. The work led to the development of a nanocomposite material, patented by the National Institute for Nuclear Physics (INFN) and Sapienza University of Rome, known as Dragon Copper, consisting of a pure copper matrix reinforced with CNTs. NIR spectroscopy revealed that the addition of a small amount of CNTs (0.1 wt%) into the copper powder efficiently reduces its reflectivity across all investigated wavelengths, including 1064 nm, the operating wavelength of the PBF-LB laser employed in this study. Thanks to the role of CNTs as efficient laser absorbers, Dragon Copper showed higher densification, enhanced microstructural stability and significant improvements in both tensile strength and ductility compared to pure copper, as confirmed by SEM analysis and tensile tests. Raman spectroscopy demonstrated the preservation of CNTs structural integrity after the PBF-LB process, suggesting their active contribution in mechanical reinforcement. Although moderate reductions in thermal and electrical conductivities, the overall performance of Dragon Copper demonstrates the potential of this approach for advancing PBF-LB manufacturing of high-performance copper components
Migraine treatment. What have we learned from neurophysiology?
No full textWhile several medications for treating migraine are widely utilized in clinical practice, their mechanisms of action at the brain level remain unknown. Several studies have employed different electrophysiological techniques to examine the neurological impacts of various preventive therapies and immediate interventions.
Overall, data analysis in patients with episodic migraine indicates that different preventive treatments can lead to a restoration of normal physiological function in a specific electrophysiological test after the clinical improvement caused by the investigated treatment. Therapies for chronic migraine can cause an electrical desensitization, resulting in a pattern similar to that found in episodic interictal migraine. Specific electrical characteristics of the brain in individuals with migraine can be utilized to predict whether therapy will result in a positive or negative change in their clinical condition.
Employing various methodologies to investigate distinct brain areas in a single patient and repeated measurements over time can enhance our comprehension of the precise location and timing of changes generated by therapy
Perceived Social Exclusion during the COVID-19 Pandemic: a European Perspective
No full textThis paper aims to study the self-perceived social exclusion of EU citizens during the COVID-19 emergency, taking into account their socio-demographic characteristics and the specific contexts of their countries of residence. To this end, we draw on data from the third round of the electronic Eurofund Living, working and COVID-19 survey, conducted between February and March 2021, when countries were still grappling with various levels of lockdown and individuals had been living with COVID-19 restrictions for almost a year. We also rely on data from the Oxford COVID-19 Government Response Tracker (OxCGRT), which collected real-time information on government responses to COVID-19 in several countries during the pandemic crisis. We assume that during the pandemic, government accountability and responsiveness were important determinants of social inclusion and well-being. To test our hypothesis, we use multilevel logistic regression. Our dependent variable is a binary indicator of social exclusion. At the country level, we consider two different sets of explanatory variables concerning, respectively, subjective (i.e., citizens' perceptions) and objective (i.e., measures taken) aspects of governments' responses to COVID-19. Our results document a different gradient of social vulnerability across population groups. Our findings also indicate that social exclusion strongly depended on the country context, in addition to individual characteristics and circumstances. Collective perceptions of the efficiency of government responses and levels of trust in government had a positive association with the decrease in the feelings of social exclusion during the first year of the pandemic. Conversely, the objective measures implemented by national governments to mitigate socio-economic and health consequences were not associated with self-reported experiences of social exclusion
A Numerical Framework for Analyzing the Multidimensional Effects of Inhomogeneous Heating in Nuclear Thermal Propulsion Reactors
No full textNuclear thermal propulsion is a promising technology for interplanetary missions thanks to its higher specific impulse and increased payload capacity relative to chemical propulsion. Earlier designs relied on highly enriched uranium, but proliferation concerns have shifted interest toward reactors fueled with high-assay low-enriched uranium. To maintain compact reactor configurations under these reduced enrichment levels, moderator elements are introduced in the reactor core to enhance neutron thermalization. This design choice alters the neutronic behavior of the system, changing how power is distributed across the core. Whereas earlier nuclear thermal propulsion reactors exhibited nearly uniform power generation across the fuel-element cross section, modern low-enrichment concepts show significant power peaking near moderator regions. This non-uniformity challenges traditional designs based on evenly spaced propellant channels, potentially leading to localized hot spots and steep thermal gradients. Since overall engine performance is constrained by material temperature limits, achieving a uniform propellant temperature at the reactor outlet becomes a central design requirement. In this work, we present a numerical framework for the steady-state design and analysis of nuclear thermal propulsion reactors, integrating system-level requirements with neutronic calculations and detailed three-dimensional thermodynamic simulations. The methodology captures the strong physical coupling among these domains, which is essential for predicting realistic reactor-core behavior. To demonstrate its capabilities, the framework is applied to a representative low-enrichment reactor concept. The results highlight the importance of a multiphysics approach for designing next-generation nuclear thermal propulsion systems and explicitly reveal the inter-dependencies between individual solvers, providing insights into the approximations and limitations inherent to single-physics analyses
Catalogazione e studio di una raccolta romana di incisioni (XVIII-XIX sec.). Il fondo di matrici Monte di Pietà-Ministero del Tesoro (Istituto Centrale per la Grafica)
No full textLa ricerca nasce dalla constatazione che nulla si sapeva finora sulle dinamiche di costituzione del fondo di matrici calcografiche entrate alla Calcografia Regia nel 1913 e provenienti dal Monte di Pietà di Roma. A partire da questa lacuna storiografica, la tesi si propone di indagare le modalità di deposito presso il Monte di Pietà di matrici incise appartenenti a serie molto note e a incisori ed editori di primo piano, al fine di ricostruirne la provenienza, le circostanze di impegno e le successive dinamiche di acquisizione pubblica.
L’indagine, fondata su un’ampia base documentaria inedita conservata presso l’Archivio storico della Fondazione Roma e l’Archivio di Stato di Roma, analizza le pratiche di credito su pegno applicate a beni artistici e tecnici, con particolare riferimento alle matrici calcografiche, collocando tali operazioni nel più ampio contesto del mercato editoriale e della produzione incisoria romana dell’Ottocento. Attraverso lo studio di fascicoli, perizie e corrispondenze - tra cui i casi di Carlo Losi, Giuseppe Antonio Monaldini e Giovanni Pietro Campana - la tesi ricostruisce i meccanismi istituzionali e i criteri di valutazione economico-artistica adottati dal Monte di Pietà, evidenziando come il ricorso al credito rappresentasse per incisori ed editori una strategia di sopravvivenza economica in una fase di progressiva contrazione del settore.
La seconda parte del lavoro è dedicata al fondo “Monte di Pietà – Ministero del Tesoro”, oggi conservato presso l’Istituto Centrale per la Grafica, che raccoglie 1.979 matrici incise di straordinario valore storico e documentario. La ricerca ne fornisce una descrizione approfondita, con particolare attenzione agli aspetti di conservazione e restauro, e documenta la campagna di interventi avviata in collaborazione con l’Istituto: 168 matrici sono state restaurate secondo i nuovi protocolli tecnici definiti dal Laboratorio Diagnostico per le Matrici dell’Istituto Centrale per la Grafica e documentati all’interno della tesi. Gli interventi, volti al ripristino della leggibilità e alla tutela del supporto metallico, hanno permesso di identificare numerose matrici finora anonime e di chiarirne le relazioni con i documenti dell’istituzione di provenienza.
Completano la tesi un catalogo ragionato delle matrici identificate - articolato in incisioni di traduzione e incisioni in serie - e due appendici documentarie che riportano in trascrizione integrale le fonti d’archivio utilizzate.
Nel loro insieme, i risultati restituiscono per la prima volta un quadro organico delle interazioni tra credito, arte e istituzioni nella Roma ottocentesca, rivelando come il Monte di Pietà sia stato un luogo di mediazione economica e culturale fondamentale per la storia della calcografia. Le matrici, da strumenti tecnici della produzione, diventano così documenti storici e beni patrimoniali, testimoniando la trasformazione del valore dell’immagine e il passaggio dall’economia dell’incisione alla costruzione della memoria grafica di Roma, poi confluita nelle raccolte pubbliche del nuovo Stato unitario
Visual Politics at the Time of Platform Society
No full textVisual Politics has its roots in the history of political communication, and it takes on particular relevance in the contemporary media scenario, together with the assumption of centrality of social media. The chapter begins with a brief history of the role of image in electoral campaigns. The contribution of Visual Politics properly so-called is presented through the evolution of the theoretical framework and exemplary research conducted over time, first in the television field then in the social media field. The social media environment is then identified as an exemplary place where Visual Politics can express its potential in the hybridization of research methods belonging to the sociology of communication and computer sciences. Some first evidence on the contribution of Computer Vision to the study of the 2024 European Elections, provided by two joint research programs in which the authors are involved, are presented
The Aniene Valley and the Sacred: A Reading in Motion
No full textThis contribution analyzes the Aniene Valley as a historical and cultural construct in which the sacred acts as the organizing principle of the landscape. Through an interdisciplinary perspective—historical, archaeological, morphological, and symbolic—it identifies the stratification of rock sanctuaries, necropolises, churches, hermitages, and monasteries, from pre-Roman cults to Benedictine monasticism, highlighting the relationships between devotional settlements, natural resources, and travel networks. The territorial organization along four geographical lines allows us to read the progressive transformation of sacred forms in relation to topography and settlement processes. What emerges is an interpretation of the valley as a coherent system of material and immaterial permanence, in which architecture, nature, and collective memory contribute to the definition of a landscape and cultural identity
Exploiting the Potential of Multi-Frequency Satellite Synthetic Aperture Radar Data for Ground Deformation and Soil Moisture Monitoring of Unstable Ground
No full textMonitoring slow-moving landslides is challenging because the principal precursors—sub-canopy soil-moisture fluctuations and millimeter-scale ground motion—occur at mismatched spatial and temporal scales. Multi-frequency satellite synthetic aperture radar (SAR) datasets were employed to monitor both processes across the Petacciato landslide in the Molise region of Italy, linking soil-moisture dynamics with deformation patterns within a spatially and temporally consistent, physically interpretable framework.
This research advances by applying radiative transfer models, which are widely used for soil moisture retrieval; however, their application to L-band SAR data remains comparatively limited. This study presents a comprehensive retrieval framework based on SAOCOM L-band dual-polarization observations (VV–VH) and the bistatic first-order radiative-transfer model (RT1), previously validated with ASCAT scatterometer and Sentinel-1 C-band SAR. The RT1 model was applied to SAOCOM acquisitions over the Petacciato landslide spanning January 2021 to December 2023. Soil-moisture estimates derived from L-band measurements (λ ≈ 23 cm) were statistically evaluated against regional reference products (ASCAT, ERA5-Land, and SMAP) using time-series comparisons and standard performance metrics. The analysis additionally incorporated the Antecedent Precipitation Index (API) to represent soil wetness carry-over from preceding rainfall. The RT1-based retrievals demonstrated strong consistency with reference datasets, achieving correlations of up to r ≥ 0.67 (e.g., relative to ASCAT). To evaluate high-resolution performance, in-situ soil-moisture sensors will be deployed on 23 March 2025, with data acquired between 25 March and 25 September 2025 using multi-frequency SAR observations from SAOCOM L-band, Sentinel-1 C-band, and CosmoSkyMed X-band. RT1 parameterization incorporated leaf-area-index (LAI) inputs at two spatial resolutions: a 50 m product and a 300 m Copernicus product, with parameter settings optimized independently for the L-, C-, and X-bands. Relative to in-situ observations, SAOCOM L-band data exhibited the strongest agreement at both 50 m and 300 m resolutions, yielding a maximum Pearson correlation of r = 0.76 and an RMSE = 0.23m3 m−3. At 300 m spatial resolution, SAOCOM L-band soil moisture estimates exhibited the consistent correlation with in-situ measurements, outperforming both Sentinel-1 C-band and CosmoSkyMed X-band retrievals. The Bayesian dual-frequency fusion (L + C) further enhanced accuracy r = 0.63 and generated uncertainty-aware soil-moisture estimates. The resulting soil-moisture fields provide reliable inputs for shallow-landslide numerical modelling of a representative test slope, enabling enhanced spatial and temporal analysis in landslide-prone terrain, including agricultural and other heterogeneous land covers.
Monitoring slow-moving landslides is essential for effective risk prevention and mitigation. Persistent Scatterer Interferometric Synthetic Aperture Radar (PS-InSAR) provides precise measurements of ground deformation in landslide-prone terrain. In this study, PS-InSAR line-of-sight displacement time series from CosmoSkyMed (ascending and descending orbits) were analysed for the Petacciato slow-moving landslide over the period 2011–2022. API derived from cumulative rainfall, was used as a proxy for antecedent wetness to evaluate its relationship with landslide reactivation. Sequential Turning Point Detection (STPD) was applied to the PS-InSAR time series to identify statistically significant trend reversals, and their co-occurrence with API threshold exceedances was assessed within a two-month window. A correspondence of 38% was observed for the ascending track and 52% for the descending track. Consistency between satellite- and ground-based precipitation estimates was confirmed using Global Precipitation Measurement (GPM) data and local rain-gauge records, yielding strong correlations (r ≥ 0.85). Notably, prominent API peaks preceded major STPD-identified reversals during 2015–2019; in March 2015, a pronounced reversal coincided with the highest API values (≥ 90 mm). Independent soil-moisture retrievals from Sentinel-1 using the RT1 algorithm showed a maximum on 25 March 2015, aligning with the detected turning point. Integrating PS-InSAR deformation metrics with antecedent wetness indicators enhances the identification of time windows conducive to landslide reactivation and supports the development of operational risk-management strategies in unstable terrain. Ground deformation was further examined using Sentinel-1 C-band and SAOCOM L-band data. In the heavily vegetated study area, coherence at X- and C-band was often reduced, limiting the spatial density of persistent scatterers and distributed scatterers outside urban settings or sites with corner reflectors. By contrast, the longer wavelength of SAOCOM L-band provided improved canopy penetration and a higher PS density; ascending and descending acquisitions collected between 2021–2025 were processed accordingly. The L-band phase-to-displacement conversion factor was approximately 0.94 cm per radian, indicating centimetre-scale sensitivity in the line of sight. The LOS velocity observed ranging from -10 mm/year to -40 mm/year in a active landslide zones. Overall, SAOCOM L-band demonstrated superior sensitivity to ground deformation beneath vegetation canopies, capturing centimetre-scale displacements, whereas CosmoSkyMed X-band performed best in built-up areas, resolving millimetre-scale motion.
The research further advances through the development of the state-of-the-art PS–SMaRT (Persistent Scatterer–Soil Moisture Analysis for Risk and Triggering), an automated processing pipeline that integrates PS–InSAR deformation data with hydro-geomorphic indicators to detect unstable slopes and derive corresponding hazard indices. Line-of-sight (LOS) velocities and displacement time series are projected onto the local downslope direction using slope, aspect, and sensor geometry, and subsequently filtered by slope and displacement-magnitude thresholds. Spatially coherent instabilities are delineated using the DBSCAN density-based clustering algorithm, vectorized into polygons, and characterized through descriptive statistics. Optional analytical modules quantify correspondence with wet-anomaly rasters using Pearson’s χ2 and the Matthews correlation coefficient, and compare topographic wetness index (TWI) values inside versus outside unstable polygons using Welch’s t-test. A normalized composite of available layers (e.g., slope, wet anomaly, TWI) is used to derive a hazard index and generate a categorical hazard map, with polygon-level zonal summaries and tabular outputs. The system ensures full provenance tracking and logging, exports outputs in raster, vector, and spreadsheet formats, and incorporates a Streamlit-based user interface for interactive execution and rapid visualization of products. The methodological advances in this thesis demonstrate how open-source, reproducible workflows can transform multi-frequency satellite data into actionable insights for landslide monitoring, and infrastructure resilience. These approaches provide a scalable foundation for future SAR missions such as NASA–ISRO’s NISAR and ESA’s ROSE-L, enabling long-term, high-resolution assessment of soil–vegetation–slope interactions