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DESIGN AND STUDY OF THE IRIS 10 T ENERGY SAVING DIPOLE MAGNET FOR ACCELERATORS: ESMA
No full textThe research and development of new superconducting materials is progressively refining the manufacturing of a new class of conductors: REBCO tapes. Although REBCO was discovered in 1987, tape manufacturing suitable for magnet windings has only recently been optimized. REBCO tapes belong to the class of High Temperature Superconductors (HTS), a class of materials which remain superconducting at temperatures higher than liquid nitrogen, in contrast to classical Low Temperature Superconductors (LTS) that require liquid helium refrigeration. This capability has the potential to transform superconducting magnet technology by enabling a wide range of applications in medical, energy, and societal domains beyond particle accelerators. The possibility of operating at higher temperatures simplifies infrastructure and improves thermal efficiency, yielding substantial energy savings and making the technology more sustainable. However, manufacturing challenges as sudden localized performance drops and unforeseen defects occurrences as well as the early stage of understanding of these conductors make a reliable application a challenging quest.\\
The objective of this thesis is to set an initial milestone toward a new generation of superconducting dipole magnets by exploiting REBCO tapes to realize a complete HTS technological demonstrator. Within the IRIS project, funded by the NextGeneration EU (PNRR), the Energy Saving Magnet for Accelerators (ESMA) was conceived to reach a peak central field of 10 T and to operate cryogen-free at 20 K, thus yielding more than competitive conductor performance with respect to classical LTS while delivering an estimated energy saving relative to operation at 4.2 K of roughly a factor five. The project is a collaboration with industry, ASG Superconductors, for magnet construction and co-design.\\
This thesis addresses the challenges of designing an HTS dipole magnet, beginning with the electromagnetic configuration while accounting for the mechanical constraints of using tape rather than round wire or cable. The procured tape was extensively characterized through electrical and mechanical measurements to provide insight for the design phase and to build in-house expertise at the LASA laboratory.
After completing the integrated electromagnetic, mechanical, and thermal design, the operation of the magnet was studied with dedicated analyses aimed at optimizing charging procedures while respecting thermal limits, critical since ESMA will also serve as a variable field user facility at INFN Genova.
Quench dynamics and AC losses were investigated in collaboration with Little Beast Engineering, to prepare an intervention or mitigation strategy in case of quench and to confirm a reliable operation. Lastly, an experimental campaign was carried out to design, manufacture, and test small HTS windings to validate handling and winding procedures, to study tape behavior under realistic processing, and to confirm the design assumptions used for ESMA
LPS-Stressed bovine endometrial cells upon morulae in a transwell model of embryo—maternal talk
No full textDuring the preimplantation period, the nutrition of the embryo is dependent on luminal secretions of the uterus, which can be modified by the health status of the animal. The aim of this study was to mimic the paracrine communication between healthy or LPS-stressed epithelial endometrial cells (EECs) and embryos using aa transwell plate. The rate of in vitro embryo production, size, and concentration of extracellular vesicles (EVs), and level of secretion of Galectin-9 (Gal-9) and leukaemia inhibitory factor (LIF) were detected. Embryos were produced with an established protocol of oocyte in vitro maturation (IVM), in vitro fertilization (IVF), and in vitro embryo culture (IVC). On day 55 of IVC, one hour before the transfer of morulae in the basolateral compartment of the transwell, EECs were treated with 10 ng/mL of LPS, and IVC was continued until the eleventh day. Extracellular vesicles (EVs) were obtained from IVC medium by ultracentrifugation. Levels of Gal-9 and LIF were evaluated by ELISA. On day 7, the results did not show statistically different blastocyst rates between EECs+Embryo and EECs+LPS+Embryo (34.94 ± 1.95% and 33.06 ± 3.08%, respectively). On day 11, the rate of hatched blastocysts was 23.03 ± 3.18% in EECs+Embryo, while in EECs+LPS+Embryo, no hatching was observed. Nanosight revealed higher values in EV size and concentration in EECs+LPS+Embryo medium compared to EECs+Embryo (p < 0.05). In LPS-treated samples, there was a significant decrease in Gal-9 levels and a significant increase in LIF secretions compared with non-non-LPS-treated samples (p < 0.05). These results highlight how bidirectional secretions between EECs and embryos, crucial for embryo development, can be affected by endometritis
Active interrogation of underground piezoelectric fabrics using high energy muon beams propagating across seismogenic faults
No full textAMPHOTERIC POLYAMIDOAMINES AS FUNCTIONAL SPECIALTY POLYMERS
No full textThis doctoral research centered on the synthesis and characterization of amphoteric polyamidoamines in both linear and cross-linked forms. The study is organized into two main thematic lines, each comprising multiple projects. The first one was to evaluate the potential environmental impact of amphoteric water-soluble PAAs, which may accidentally be released into ecosystems during or after their useful life. The ecotoxicity of PAAs was evaluated on the early stages of plant development using Lepidium sativum (watercress) seeds. In this study, the effectiveness and robustness of the seed germination test for assessing the phytotoxicity of water-soluble polymers has been investigated. Several parameters have been considered to assess the response of seeds exposed to PAA water solutions at different concentrations, including germination percentage, root and bud elongation. To extend the environmental toxicity assessment, the effects of PAAs were evaluated on aquatic ecosystems using zebrafish (Danio rerio) embryos, a vertebrate model organism sharing several features with mammals. Embryos development was monitored by performing the standard fish embryo acute toxicity test, evaluating the survival rate, morphological defects, organ deformities, and developmental delay compared to the control.
The second thematic line aimed at exploring PAAs versatility in diverse applications, as water solutions and as hydrogels. Linear α-amino acid-derived PAAs with varying UV-absorption characteristics were investigated as functional coatings to enhance cotton photostability in accelerated photoaging tests under UVA-UVB irradiation. To gain deeper insight into this phenomenon, the photodegradation mechanism both in solution and in the solid state was investigated during the research period at the Université Clermont Auvergne. Photodegradation was evaluated under different experimental conditions, UVA and UVC irradiation, as well as in the presence of hydrogen peroxide as an oxidative agent. PAAs were investigated also in their cross-linked form through the development of biofunctional hydrogels. Cell-adhesive PAA-based composite hydrogels reinforced with electrospun poly-L-lactic acid mats, were studied as novel biomaterials with neuroregenerative and neuroprotective properties on preneuronal and immune cell lines
EVALUATION, DEVELOPMENT, AND EXTENSION OF FLEXIBLE PARAMETRIC MODELS FOR THE DISTRIBUTIONAL ANALYSIS OF CENSORED AND NON-CENSORED DATA: A FRAMEWORK FOR MODELING AND COMMUNICATING THE FULL DISTRIBUTION OF HEALTH OUTCOMES.
No full textBackground: Time-to-event analysis is a cornerstone of medical research, yet standard methods often rely on restrictive assumptions that limit their clinical utility and causal interpretability. The Hazard Ratio (HR), while popular, suffers from non-collapsibility and lacks a straightforward causal interpretation, particularly when proportional hazards (PH) assumptions are violated. Furthermore, single-number summaries often obscure the temporal dynamics of risk, failing to communicate when a treatment is most effective.
Objective: This thesis aims to evaluate, develop, and extend flexible parametric models to improve the estimation and communication of causal effects in survival analysis. It specifically targets the robust estimation of cumulative quantities (e.g., Risk Difference, Relative Risk) and the distributional analysis of health outcomes beyond simple summary statistics.
Methods: The work explores two primary modeling pathways: (1) indirect estimation via flexible hazard-based models (Discrete-Time Hazard and Piece-wise Exponential models) and
(2) direct estimation using pseudo-observations.
• Simulation Studies: Extensive Monte Carlo simulations are conducted to determine the sample size requirements (Events Per Parameter) for these flexible models and to assess their performance under complex data-generating mechanisms (non-proportional hazards, time-varying effects).
• Model Selection: A novel statistical learning workflow is proposed, integrating bootstrap perturbation and time-dependent predictive metrics (e.g., Net Reclassification Improvement) to robustly select model complexity for the Cumulative Incidence Function
(CIF) in competing risks settings.
• New Estimators: The thesis introduces an imputation-based Piece-wise Exponential model for the direct estimation of the sub-distribution hazard.
• New Measures: To improve risk communication, two novel estimands are defined: the Highest Risk Density Region (HRDR) and the Highest Net Risk Difference Region (HNRDR). These measures identify the specific time intervals where absolute risk is most concentrated or where the treatment effect is maximal.
Results: Simulation results indicate that flexible parametric models require approximately 20 events per parameter to achieve stable estimates of causal effects on the cumulative scale. The proposed imputation-based PWE model for competing risks demonstrates negligible bias and competitive performance against established methods. The HRDR and HNRDR frameworks successfully characterize the temporal distribution of risk, distinguishing between treatments that delay event onset versus those that reduce overall event magnitude. Finally, the distributional regression framework is successfully generalized to non-censored continuous outcomes, offering a unified approach to dose-response analysis.
Conclusion: This thesis provides a comprehensive framework for the rigorous application of flexible survival models. By shifting the analytical focus from conditional rates (hazard ratios) to marginal cumulative effects and full probability distributions, it offers researchers tools to generate more causally sound, robust, and clinically interpretable evidence
New Permutationally Invariant Polynomial Potential Energy Surfaces for H5O2+ with Fast Analytical Gradients Calculated Using Reverse Differentiation
No full textGiven the central importance of the protonated water dimer to the study of the hydrated proton, we report new fits to the previous CCSD(T) data set of Huang, Braams, and Bowman (HBB) that are more precise and, unlike HBB, provide fast gradients. The new fits, like the HBB one, are based on linear regression with permutationally invariant polynomials (PIPs). The fast gradients are provided via reverse differentiation. They cost roughly just three times the cost for an energy call and are roughly 20 times faster than the HBB numerical gradients. The two new PESs are fits to the original HBB data sets up to roughly 60,000 and to 110,000 cm–1. Comparisons to the CCSD(T) benchmarks and to the HBB results for stationary points and Diffusion Monte Carlo ZPEs are reported and show good agreement
MUSICA, INDUSTRIA E POLITICA NELLA RETE PRODUTTIVA DI CASA RICORDI (1919¿1940)
No full textLa tesi ricostruisce la storia e la rete produttiva di Casa Ricordi, principale editore musicale italiano tra Otto e Novecento, nel periodo compreso tra le due guerre mondiali. L’indagine si basa sullo studio e la mappatura digitale del fondo dei copialettere aziendali dell’Archivio Storico Ricordi, relativo alla gerenza di Renzo Valcarenghi e Carlo Clausetti (1919–1940), che consente di osservare da una prospettiva ravvicinata la comunicazione quotidiana dell’editore e le interazioni con una pluralità di attori artistici, economici e politici. Adottando un metodo di narrazione microstorica, la tesi analizza le trasformazioni dell’editoria musicale nel primo Novecento attraverso quattro casi di studio, organizzati in “storie” costruite lungo il filo cronologico della corrispondenza epistolare. Queste approfondiscono: la causa tra Giacomo Puccini e Casa Ricordi del 1923 originata dalla pubblicazione non autorizzata negli Stati Uniti di fox-trot sui temi di "Tosca" e "Madama Butterfly"; la produzione nel 1930–31 del primo film sonoro a soggetto operistico, "La Wally" della Cines-Pittaluga, e i complessi rapporti con la coeva industria cinematografica; l’espansione del mercato musicale sudamericano e la penetrazione del comparto produttivo italiano attraverso l’apertura della succursale di Buenos Aires nel 1924; infine, l’evoluzione dell’ecosistema operistico sullo sfondo delle sanzioni internazionali all’Italia fascista del 1935. Ad aprire la tesi è posto uno “sfondo” teorico-analitico che rilegge la storia di Casa Ricordi alla luce di teorie sociologiche relazionali, in particolare actor-network theory e teoria della mediazione, fornendo il quadro concettuale entro cui si collocano le quattro storie.The dissertation reconstructs the history and production network of Casa Ricordi, Italy’s leading music publisher between the nineteenth and twentieth centuries, with a focus on the interwar period. It is based on the analysis and digital mapping of the company’s copy-letter books preserved at the Archivio Storico Ricordi, covering the management of Renzo Valcarenghi and Carlo Clausetti (1919–1940). These archival sources allow to examine the publisher’s day-to-day communication and its interactions with a wide range of artistic, economic, and political actors from a close, process-oriented perspective. Adopting a micro-historical approach, the dissertation explores the transformations of music publishing in the early twentieth century through four case studies, presented as “stories” unfolding along the chronological thread of the epistolary exchange. These include: the 1923 lawsuit between Giacomo Puccini and Casa Ricordi following the unauthorized publication in the United States of fox-trots based on themes from "Tosca" and "Madama Butterfly"; the production in 1930–31 of "La Wally" (Cines-Pittaluga), the first sound film with an operatic subject, and the complex relations with the contemporary film industry; the growth of the South American music market and the expansion of the Italian industry through the opening of Ricordi’s Buenos Aires branch in 1924; and the reconfiguration of the operatic ecosystem in response to the international sanctions imposed on Fascist Italy in 1935. The dissertation opens with a theoretical and analytical framework that reads Casa Ricordi’s history through relational sociological approaches, particularly actor-network theory and mediation theory, providing the conceptual lens through which the four stories are interpreted
THE MANY FACES OF REGENERATION: ENGINEERING MULTIFUNCTIONAL SCAFFOLDS FOR CRANIOMAXILLOFACIAL APPLICATIONS
No full textA mandibular bone defect is a part of the lower jaw where bone is missing. People affected by large mandibular defects face consequences that go far beyond esthetics. For example, they often struggle to chew or speak, and this can affect daily life and overall well-being. Mandibular defects can arise from congenital conditions, accidents or, in most cases, from surgical removal of tumors in the mouth. Oral cancers continue to increase worldwide and so does the number of patients who require jaw reconstruction.
To date, the gold-standard treatment has been to replace the missing bone with a piece of the patient’s own fibula, taken from the leg. However, the procedure is extremely complex. It requires long surgeries, advanced microsurgical skills, and two surgical interventions, exposing patients to pain and high-risk potential complications. In addition, the fibula does not naturally match the shape, size, or mechanical properties of the jaw. This mismatch can make it difficult to restore facial appearance or place dental implants correctly.
These limitations have motivated researchers to explore new solutions based on bone tissue engineering, a field that aims to help the body regenerate its own bone. Instead of taking bone tissue from another part of the body, scientists design 3D porous structures (i.e. scaffolds), made from biodegradable materials that temporarily support cells as they grow new bone tissue. The scaffolds can be made of different materials and can be customized to fit the shape of a patient’s defect. The use of additive manufacturing technologies to fabricate these constructs gives great freedom in terms of shape and materials. Despite many promising results, engineered scaffolds still struggle to break into clinical use, mainly due to failure in repairing large defects and ensuring vascularization.
The work described in this thesis focuses on developing new strategies to design scaffolds that can better support both bone formation and the growth of blood vessels, which are essential for the survival of newly formed tissue. We started by an analysis of the state of art (Chapter 2) to understand the main approaches that are currently being investigated and their limitations. We then explored several aspects involved in the design of a scaffold, presenting alternative or complementary solutions.
One strategy focused on the shape of the scaffold pores (Chapter 3). Inspired by natural bone structures, we developed two different pore geometries (star and diamond) and showed their influence on stem cells differentiation into bone-forming cells. We found that diamond pores enhanced expression of osteogenic genes, while the star pores promoted stronger mineral deposition. These results highlighted how geometry can guide different aspects of bone formation.
Another approach focused on the materials used to fabricate the scaffolds (Chapter 3 & 4). We proposed mixing polymers with bioactive materials containing ceramics or bioactive glasses. These materials resemble the chemical composition of natural bone and can release ions that stimulate cells to differentiate into bone-forming cells and encourage blood vessel growth. Our results showed that these composite scaffolds improved osteogenic and angiogenic marker expression in stem cells and the ability of endothelial cells to form vessel-like structures.
To accelerate biological effects even further, we also developed surface coatings to release pro-angiogenic molecules from the scaffold surface (Chapter 5). These molecules not only induced hypoxic response, pushing cells to activate formation of blood vessels, but also enhanced the differentiation of stem cells into bone-forming cells. We demonstrated that this coating triggered activation of both angiogenic and osteogenic pathways, confirming the strong interplay between these two processes.
Finally, we explored the possibility of pre-vascularizing scaffolds before implantation (Chapter 6). We created a hybrid scaffold by combining a hard scaffold with a soft hydrogel and were able to grow micro-capillary-like structures in vitro before implantation. This showed that a pre-vascularized construct could support early blood vessel organization, a critical step for improving implant integration in large bone defects.
Together, these strategies provided new insights into the design of next-generation mandibular implants. Although challenges remain before such scaffolds can fully replace current surgical approaches, the work of this thesis pushes a step closer to less invasive and more effective treatments for patients who need jaw reconstruction
Design Comparison of Four-Layer Full-NbSn and Hybrid NbSn/NbTi Cos-Theta Dipoles for the CERN High Field Magnet R&D Programme
No full textThe High Field Magnet (HFM) R&D programme at CERN aims to find technological solutions for the construction of accelerator magnets to be installed in future post-LHC colliders. The Italian Institute for Nuclear Physics (INFN) and CERN are collaborating to design and fabricate a new four-layer cos-theta dipole able to achieve a bore field of 14T with at least 20% margin on the load-line. Two design options are under evaluation: a four-layer dipole entirely made of Nb3Sn, and a hybrid configuration combining inner Nb3Sn layers with outer NbTi layers. Both options are being assessed for feasibility as short models, with scalable design choices for longer magnet prototypes suitable for accelerator integration. This paper presents a comparative study of the performance of the two design options. The results provide insights into the trade-offs between performance, complexity, and protection constraints in the development of next-generation high-field dipole magnets. The Full-Nb3Sn solution satisfies the HFM requirements, but the Hybrid solution is a promising, cost-effective alternative that can be considered for next-generation colliders
Diagnostic Accuracy of the Triglyceride-Glucose Derived Indices in Detecting Metabolic Syndrome in Pediatric Patients
No full textBackground: Given the challenges associated with direct insulin measurements, several surrogate markers combining both anthropometric data and laboratory tests (such as glucose and lipid levels) have been developed. This study aims to assess the diagnostic accuracy of the following indices: triglyceride-glucose (TyG) index, TyG index adjusted for body mass index (TyG-BMI), TyG index adjusted for waist circumference (TyG-WC), and TyG index adjusted for waist-to-height ratio (TyG-WHtR), for detecting metabolic syndrome (MetS) in the pediatric population, in comparison with conventional parameters. Methods: We retrospectively analyzed data from 746 children and adolescents (372 female/374 male) categorized into groups based on BMI z-score. Insulin resistance (IR) surrogates were calculated as: homeostasis model assessment of insulin resistance (HOMA-IR), TyG, TyG-BMI, TyG-WC, and TyG-WHtR. MetS was defined by the presence of at least three of the following components: BMI z-score ≥2 standard deviation and/or WC/height ratio ≥0.5; fasting blood glucose >100 mg/dL and/or pathological HOMA-IR; dyslipidemia; and hypertension. Results: The overall prevalence of MetS was 15.01% (112/746), occurring exclusively in children with obesity or overweight (P=0.004). The third quartile (Q3) was identified as the optimal cut-off point for the TyG indices (TyG, 8.1; TyG-BMI, 231.54; TyG-WC, 734.03; and TyG-WHtR, 4.73). The areas under the receiver operating characteristic curves (AUCs) of TyG, TyG-BMI, TyG-WC, and TyG-WHtR were 0.801 (P<0.001), 0.840 (P<0.001), 0.832 (P<0.001), and 0.816 (P<0.001) respectively, comparable to the AUC of HOMA-IR, which was 0.866 (P<0.001). Conclusion: The TyG, TyG-BMI, TyG-WC, and TyG-WHtR indices demonstrated promising predictive value for MetS in children with overweight or obesity. These markers can effectively identify high-risk individuals and offer a cost-effective alternative to direct assessment of insulin sensitivity