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2D-hybrid perovskite thin films for high energy radiation detection
Get PDFThe physics of interaction between matter and radiation constitutes the basis of dosimetry and related devices. Analyses on materials, architectures and electronic readout systems are mandatory for precise and accurate detection of the absorbed dose. Hybrid metal-halide perovskites have emerged as promising for radiation detection due to their unique chemical and optoelectronic properties. This class of materials, consisting of alternating organic and inorganic layers, exhibits semiconducting features with tuneable bandgaps, excellent charge-transport and scintillation properties and high radiation hardness, making them suitable as active layers for dosimetry devices. Furthermore, the high atomic number facilitates detection of high-energy photons and particles, allowing for specific medical and space-related applications to be targeted directly. Recent research has highlighted two-dimensional (2D) perovskites as valid alternative to the well-established 3D counterpart: reasons are to be found in higher stability and remarkably lower dark current, that lead to long-term performance and durability. Moreover, perovskite-based radiation detectors are fabricated from solution-processing techniques, which are cost-effective and scalable to large-area devices. Here, we chose PEA2PbBr4 2D-perovskite as active material in the form of polycrystalline thin films for direct detection of high energy ionizing radiation. We investigated physical and chemical properties of the material including charge-carriers mobility, lifetime, response time, photovoltage with specific techniques and designed and fabricated devices to be employed for medical and space-related applications. We tested these devices response under X- and γ-rays, under high energy protons and alpha particles. We realized the first flexible dosimeter for real-time monitoring of clinically relevant proton beam and radiotracer extravasation. We demonstrated alpha particles spectroscopy power of thin films, that is of interest for medical applications as it directly conveys towards neutron detection. Lasty, space-related
applications are targeted as a perovskite-based dosimeter is implemented to be sent to the ISS for dedicated tests with the crew onboard
A comprehensive galaxy and AGN mock catalogue for the next generation of surveys
Get PDFCurrent and future large-sky surveys will produce unprecedented amounts of photometric and spectroscopic data for billions of sources. To fully exploit the scientific potential of these surveys, realistic simulations of astrophysical sources such as galaxies and Active Galactic Nuclei (AGN) have become essential tools. In this context, we introduce a new, flexible, and efficient computational model designed to simulate mock catalogues of galaxies and AGN that accurately replicate the statistical properties and observational features of these astrophysical sources. To achieve this, we followed a completely empirical approach, that is, we calibrated the model based on observed scaling relations. Specifically, we started with simulated dark matter (DM) haloes from an N-body simulation, to preserve the link with the cosmic web, and we populated them with galaxies and AGN using abundance matching techniques. To achieve this, we used several observational inputs, such as
stellar mass functions, host galaxy AGN mass functions, and AGN accretion rate distribution functions studied at different redshifts to assign, among other properties, stellar masses, the fraction of quenched galaxies, or the AGN activity (demography, obscuration, multiwavelength emission, etc.). As a proof test, we applied the method to a Millennium DM lightcone of 3.14 deg2 up to a redshift of z = 10. We show that the AGN population from the mock lightcone presented here reproduces with good accuracy various observables, such as state-of-the-art luminosity functions in the X-ray and in the ultraviolet, near-infrared colour-colour diagrams, and narrow emission line diagnostic diagrams. Finally, we demonstrate several applications of this catalogue. We computed several forecasts of Euclid observations, and we tested a pipeline for retrieving photometric redshifts on simulated AGN with Euclid-like photometry and a spectroscopic analysis pipeline on Euclid-like AGN spectral energy distributions. Finally, we show an application of this model for the preparation of an X-ray observational campaign
Thresholds and folds of the digital apparatus. Towards a unified semiotics for digital media
Get PDFLa ricerca si pone come riflessione sui fenomeni della digitalizzazione all’interno del campo della semiotica dei media. Se la semiotica si è infatti interessata all’analisi di specifici linguaggi legati all’uso e al consumo di tecnologie digitali, il fenomeno culturale della digitalizzazione è stato fino ad ora poco problematizzato in maniera specifica da parte della scienza della significazione. Per questo motivo, lo studio si occupa da un lato di investigare il rapporto materiale, tecnico ed estetico con l’oggetto tecnologico mediale, e dall’altro di delineare i modelli interpretativi – e quindi socialmente, culturalmente e storicamente determinati – che guidano l’approccio a diversi media, evitando i determinismi tecnologico e sociale ma prendendo in considerazione la relazione materiale con il supporto come costitutiva dei processi di significazione. Il lavoro parte da una disamina degli approcci semiotici, filosofici ed estetici alle mediazioni, sia dal punto di vista tecnico che da quello semiolinguistico, per interrogare la relazione che si pone in apparenza come quella tra un soggetto-utente e un oggetto-supporto; prosegue poi nell’identificazione della digitalizzazione come campo di studi che permette l’emersione e l’individuazione di problemi squisitamente semiotici quali l’enunciazione attraverso la tecnologia, la comparsa di nuove intermediazioni e la costruzione di percorsi interpretativi all’interno del disordine informativo.The research presents itself as a reflection on the phenomena of digitalization within the field of media semiotics. While semiotics has indeed been concerned with analyzing specific languages related to the use and consumption of digital technologies, the cultural phenomenon of digitalization has so far been little problematized in a specific way within the science of signification. For this reason, the study focuses on investigating, on one hand, the material, technical, and aesthetic relationship with the technological media object, and on the other, on outlining the interpretative models—thus socially, culturally, and historically determined—that guide the approach to different media. It aims to avoid both technological and social determinisms while considering the material relationship with the medium as constitutive of signification processes. The work begins with an examination of semiotic, philosophical, and aesthetic approaches to mediations, both from a technical perspective and from a semiolinguistic one, in order to question the relationship that seemingly appears as one between a subject-user and an object-medium. It then proceeds to identify digitalization as a field of study that allows for the emergence and identification of strictly semiotic issues, such as enunciation through technology, the appearance of new intermediation forms, and the construction of interpretative paths within informational disorder
Learning and optimal control of uncertain systems via data-driven methods with stability guarantees
Get PDFWith the advent of largely available computational power and datasets, a broad number of new algorithms for learning and control of dynamical systems has been proposed; however, the complexity of the considered frameworks has outpaced the theoretical analysis of these new techniques. To reduce this gap, this thesis focuses on the development of theoretical tools and control algorithms for the learning and optimal control of uncertain systems. The main challenges in these frameworks regard the problems of i) guaranteeing informative systems trajectories, ii) extracting the information from measurable quantities and iii) designing stabilizing and optimal control laws from gathered data. We start by addressing the problem of giving Persistency of Excitation (PE) guarantees in the context of Linear Time-Invariant (LTI) systems, finding necessary and sufficient conditions to obtain this property via an input signal. Our results are developed within a notation which underlines the perfect analogies between the continuous- and discrete-time frameworks. Next, we study data-driven approaches for the stabilization of LTI systems. We start by addressing the design of model-free observers that extract full-state information from output data, and we proceed with the design of controllers via LMIs when state measurements and derivatives are unavailable. Next, we consider the Linear Quadratic Regulator (LQR) problem, and we propose a nonlinear on-policy controller which globally converges to the optimal feedback preserving the stability of the interconnection during the transient. Finally, leaving the linear framework, we design a model-free optimal control algorithm which, differently from other techniques, takes into account the problem of safety whilst performing the necessary exploration. A distinctive feature of this thesis is its retrospective look at classical techniques and concepts from the adaptive and linear multivariable control field, which we repropose in combination with more recent approaches and which we believe hold the answers to many current questions
Assessment of SARS-CoV-2 in workplace and community settings: an innovative environmental surveillance approach to prevent COVID-19 infection
Get PDFThis project arises from the need to respond to the uncontrolled spread of future infectious diseases by applying the lessons learned from the COVID-19 pandemic. These include the numerous lives lost, the stress conditions experienced by the healthcare workers and the economic impact on nations. In particular, the project aims to highlight how an interdisciplinary approach can make the difference in managing large-scale health emergencies. It underscores the importance of studying a pathogen's environmental behavior to anticipate and react to outbreaks before they escalate into full- blown health crises. From these premises, the first phase of the study aims to assess the presence of SARS-CoV-2 in healthcare and community settings through surface sampling and analysis. The collected samples were analyzed using three molecular biology techniques: RT-qPCR, ddPCR, and RT-LAMP method. With the exception for RT-LAMP, this phase of the project involved clinical assays to perform molecular biology analysis. The second phase was focused on performing RT-qPCR of the same samples, using an assay specifically developed for surface samples. The comparison among techniques allowed the identification of the most suitable approach for surface monitoring. By building on the foundation laid in these aims, the following research will contribute to a greater understanding of how environmental monitoring can be optimized and implemented as part of a comprehensive strategy against not just COVID-19, but also for other infectious diseases. The GVM Care & Research Group has contributed to the study by allowing access to its facilities to support environmental sampling campaign. In particular, the sampling campaign was carried out mainly at the Maria Cecilia Hospital in Cotignola (RA), which was designated as the partner company for this PhD project
Calvino, Bassani, and hyperobjects: literature beyond Nature
Get PDFQuesto studio esamina le opere di Giorgio Bassani e Italo Calvino attraverso un approccio ecocritico, basandosi sulla teoria degli Iperoggetti di Timothy Morton. Queste entità—vasto estese, non locali e temporalmente diffuse—sfidano le tradizionali modalità di percezione e rappresentazione, ridefinendo il rapporto tra esseri umani e ambiente. Applicando questo concetto, la ricerca esplora come Bassani e Calvino affrontino questioni ecologiche, rivelando l’intricata interconnessione tra il mondo umano e quello non umano. La scrittura di Bassani riflette una profonda sensibilità nei confronti dei paesaggi, intesi non solo come spazi fisici, ma anche come luoghi di significato storico ed esistenziale. La sua attenzione agli elementi naturali suggerisce una consapevolezza di strutture ecologiche più ampie, che trascendono l’esperienza individuale. Il lavoro di Calvino, invece, interroga spesso i limiti della percezione umana nei confronti della natura, adottando forme narrative sperimentali per rappresentare la complessità dell’interconnessione ambientale. Entrambi gli autori, seppur con approcci diversi, anticipano il discorso ecologico contemporaneo, mettendo in discussione la prospettiva antropocentrica e ponendo la natura come forza attiva piuttosto che come semplice sfondo. Integrando gli strumenti teorici di Morton con l’analisi letteraria, questa ricerca dimostra come questi testi esprimano la presenza degli iperoggetti—fenomeni troppo vasti per essere pienamente compresi, ma profondamente radicati nell’esistenza umana. Il loro confronto con le tematiche ecologiche evidenzia la necessità di nuovi paradigmi interpretativi, che superino le rappresentazioni convenzionali della natura.This study examines the works of Giorgio Bassani and Italo Calvino through an ecocritical framework, drawing on Timothy Morton’s theory of Hyperobjects. These entities—massive, nonlocal, and temporally dispersed—challenge traditional modes of perception and representation, reshaping human interactions with the environment. By applying this concept, the research explores how Bassani and Calvino engage with ecological concerns, revealing the intricate entanglement between human and nonhuman worlds. Bassani’s writing reflects a deep sensitivity to landscapes as both physical spaces and sites of historical and existential significance. His attention to environmental elements suggests an awareness of broader ecological structures that transcend individual experience. Calvino’s work, in contrast, often interrogates the limits of human perception in relation to nature, employing experimental forms to depict the complexities of environmental interconnectivity. Both authors, in different ways, anticipate contemporary ecological discourse by challenging anthropocentric perspectives and foregrounding nature as an active force rather than a passive backdrop. By integrating Morton’s theoretical insights with literary analysis, this research demonstrates how these texts articulate the presence of hyperobjects—phenomena too vast to be fully grasped yet deeply embedded in human existence. Their engagement with ecological themes highlights the necessity of new interpretative paradigms that move beyond conventional representations of nature
Supergeometry, noncommutative geometry and invariant theory
Get PDFThis thesis covers various questions in supergeometry, noncommutative geometry and invariant theory. A brief summary is given below. The fundamental theorems of invariant theory characterize the ring of invariants in C[Mr×p] under a canonical action of special linear group SLr(C). In this case, the generators correspond to the r × r minors and satisfy Pl¨ucker relations. We present here a super version of this question. We prove the first fundamental theorem for the case of special linear supergroup SL(r|s). By employing an approach based on the Jacobi’s identity, we establish certain relations, what we refer to as super Pl¨ucker relations. For the case of SL(1|1), we prove that these super Pl¨ucker relations completely characterize the ring of invariants. In a recent work by Buachalla and Somberg, Lusztig’s positive root vectors, with respect to a distinguished choice of reduced decomposition of the longest element of the Weyl group, were shown to give a quantum tangent space for every A-series full quantum flag manifold Oq(Fn). Moreover, the associated differential calculus Ω(0,•)q(Fn) was shown to have classical dimension. Here we examine in detail the rank two case, namely the full quantum flag manifold of Oq(SU3). In particular, we examine the ∗-differential calculus associated to Ω(0,•)q(F3) and its non-commutative complex geometry. A quantization of the complex Minkowski space due to R. Fioresi and others, is well-known. We extend this approach to the case of N = 2 Minkowski superspace. We give the superalgebra of N = 2 antichiral quantum superfields realized as a subalgebra of the quantum supergroup Cq[SL(4|2)]. The multiplication law in the quantum supergroup induces a coaction on the set of antichiral superfields. We also realize the quantum deformation of the Minkowski superspace as a quantum principal bundle
Towards the scenic gender. Recycling the actor's gender through the Naghsh-poosh imitation technique [dressing the figure]
Get PDFLa presente investigación tiene como objetivo aplicar las teorías feministas y de género, junto con los métodos y prácticas teatrales, para proponer una guía de interpretación de carácter no binaria e inclusiva, que explore el papel del género en el trabajo del intérprete. Para ello, a través de la contextualización del reciclaje en el teatro, estudiamos las estrategias de deconstrucción y reformulación del género, su performatividad y sus comportamientos corporales en la interpretación de los personajes teatrales: Clitemnestra en La Orestea (Esquilo, 2021), del teatro griego; Isabella de Valois en Ricardo II (Shakespeare, 1997 y 2008), del teatro isabelino; y Sayyidah Zaynab en el Sermón de la señora Zaynab en Damasco (2024 [En línea]), de la práctica teatral Ta’ziyeh. El objetivo final es alcanzar un género escénico: un cuerpo vivo, con apariencia y comportamientos ambiguos; un agente actuante que abandone los valores patriarcales y sea capaz de interpretar cualquier personaje teatral, más allá de los límites de género/sexo, edad, raza, color, etc. Un género/cuerpo reciclado que, a su vez, provocará el reciclaje de los demás elementos escénicos, es decir, espacio, texto, tiempo y público, generando un efecto dominó en el que la deconstrucción y/o el cambio de uno de los componentes afecta a todos los demás.This research applies feminist and gender theories, along with theatre acting methods and practices, to propose a non-binary inclusive interpretative approach that explores the role of gender in the work of the actor/performer. Through the contextualization of the term “recycling” in a theatrical context, the aim is to define strategies for deconstructing and reformulating gender narratives, performativity, and bodily behaviors in theatre. To achieve this objective, the focus is on the acting process of the following characters: Clytemnestra (Aeschylus, 2021), Isabella of Valois (Shakespeare, 1997 & 2008), and Sayyidah Zaynab (2024 [Online]). The goal is to define 'Scenic Gender': an alive body with ambiguous appearances and behaviors; a doer-actor-performer agent who rejects patriarchal values and is capable of playing any role, beyond the limits of gender/sex, age, race or ethnicity. This concept of a recycled gender-body, in turn, provokes the recycling of other theatre elements—space, text, time and audience—creating a domino effect in which the deconstruction and/or alteration of one component influences all others
BRAFV600E-mutated colorectal cancer: primary and acquired resistance to targeted treatment (MASCARA study)
Get PDFBRAF-mutant metastatic colorectal cancer (mCRC) is a clinically aggressive subtype with limited treatment options and poor prognosis. The BRAFV600E mutation, found in approximately 10% of CRC cases, is associated with rapid disease progression and resistance to standard therapies. Although combination treatments such as Encorafenib and Cetuximab have shown clinical benefit, predictive biomarkers for response remain largely undefined. The MASCARA study investigates the clinical and molecular characteristics of BRAF-mutant mCRC, aiming to identify biomarkers predictive of treatment response. A cohort of 50 patients, with 30 evaluated for clinical and genomic data, was analyzed using whole-exome sequencing (WES), circulating tumor DNA (ctDNA) profiling, and spatial transcriptomics. Preliminary results show a median age of 69 years, a predominance of female patients (70%), and tumors primarily located in the right colon (80%). Liver (40%) and lung (30%) were the most common metastatic sites. RECIST-based assessment revealed that 20% of patients achieved complete or partial response, while 80% were non-responders.
Genomic profiling confirmed BRAFV600E in all cases and identified frequent alterations in TP53, BRINP3, NOTCH3, LRP2, and FBXW7. Most tumors were microsatellite stable (80%) with high tumor mutational burden (TMB-H, 87%). Resistance-associated mutations (e.g., RAS, PIK3CA, SMAD4) were detected via ctDNA, suggesting clonal evolution during treatment. Spatial transcriptomics highlighted immune-related differences between responders and non-responders. Responders exhibited upregulation of antigen presentation genes (CD74, HLA-DRA, HLA-DRB), indicating a more immune-permissive tumor microenvironment (TME). In contrast, non-responders showed enrichment of immune evasion markers (SSX1, CCL15) and downregulation of tumor suppressors (ACTB, EPCAM).
Pathway analysis revealed enrichment of immune activation in responders and survival/immune evasion pathways (e.g., FGFR2, GPCR signaling) in non-responders. These findings underscore the combined impact of genetic alterations and TME composition in modulating therapy response and support the development of personalized therapeutic strategies
Technological, sensory, and nutritional assessment of ecofriendly food lipids
Get PDFThe food industry relies heavily on fats and oils of both animal and vegetable origin, with global consumption reaching 416 million tons in 2023 and expected to double in the next 30 years. Regulatory changes, notably European Regulation 2019/649 amending Regulation 1925/2006, have prompted a shift away from trans fats and hydrogenated oils, leading to increased palm oil usage. Italy’s palm oil imports for food grew significantly, reaching 77,000 tons in 2011, and positioning Italy as the seventh largest importer globally in 2022, with imports valued at $1.65 billion. Although palm oil offers high productivity and technical advantages, it faces scrutiny due to nutritional and environmental concerns. Advances in production and RSPO-certified sustainable palm oil have addressed some issues, but challenges remain due to cost, limited availability, and consumer skepticism. This research explores the valorization of by-products from the wine, cereal, and tomato industries to recover valuable fatty substances, emphasizing their bioactive components such as tocopherols and sterols. The development of oil and fat mixtures incorporating these by-products aims to improve formulation safety, extend shelf life, and prevent lipid oxidation. Italian cereal by-products, including rice germ and wheat germ—by-products of rice husking and durum wheat processing respectively—are rich in extractable fats, particularly linoleic acid and MUFAs. In 2020, Italy produced 4 million tons of durum wheat, with its germ containing 15% fat. Grape seeds from winemaking and tomato seeds from canning also provide unsaturated fatty acids and antioxidants, which enhance thermal stability and frying performance. The thesis focuses on developing industrially viable oil mixtures using sustainable extraction, co-extraction, and refining techniques. Additionally, it proposes the implementation of rapid, non-destructive methods to assess fat quality, minimizing chemical use and supporting environmentally responsible practices across the supply chain