University of Bologna

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    Investigation of organic semiconductor/water interfaces for optobioelectronic devices

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    The thesis investigates the potential of photoactive organic semiconductors as a new class of materials for developing bioelectronic devices that can convert light into biological signals. The materials can be either small molecules or polymers. When these materials interact with aqueous biological fluids, they give rise to various electrochemical phenomena, including photofaradaic or photocapacitive processes, depending on whether photogenerated charges participate in redox processes or accumulate at an interface. The thesis starts by studying the behavior of the H2Pc/PTCDI molecular p/n thin-film heterojunction in contact with aqueous electrolyte. An equivalent circuit model is developed, explaining the measurements and predicting behavior in wireless mode. A systematic study on p-type polymeric thin-films is presented, comparing rr-P3HT with two low bandgap conjugated polymers: PBDB-T and PTB7. The results demonstrate that PTB7 has superior photocurrent performance due to more effective electron-transfer onto acceptor states in solution. Furthermore, the thesis addresses the issue of photovoltage generation for wireless photoelectrodes. An analytical model based on photoactivated charge-transfer across the organic-semiconductor/water interface is developed, explaining the large photovoltages observed for polymeric p-type semiconductor electrodes in water. Then, flash-precipitated nanoparticles made of the same three photoactive polymers are investigated, assessing the influence of fabrication parameters on the stability, structure, and energetics of the nanoparticles. Photocathodic current generation and consequent positive charge accumulation is also investigated. Additionally, newly developed porous P3HT thin-films are tested, showing that porosity increases both the photocurrent and the semiconductor/water interfacial capacity. Finally, the thesis demonstrates the biocompatibility of the materials in in-vitro experiments and shows safe levels of photoinduced intracellular ROS production with p-type polymeric thin-films and nanoparticles. The findings highlight the potential of photoactive organic semiconductors in the development of optobioelectronic devices, demonstrating their ability to convert light into biological signals and interface with biological fluids

    The RAS-Lung project: implementing blood and tissue genotyping in KRAS-Positive non-small cell lung cancer treatment

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    Background: The frontline management of non-oncogene addicted non-small cell lung cancer (NSCLC) involves immunotherapy (ICI) alone or combined with chemotherapy (CT-ICI). As therapeutic options expand, refining NSCLC genotyping gains paramount importance. The dynamic landscape of KRAS-positive NSCLC presents a spectrum of treatment options, including ICI, targeted therapy, and combination strategies currently under investigation. Methods: The two-year RASLUNG project, featuring both retrospective and prospective cohorts, aimed to analyze the predictive and prognostic impact of KRAS mutations on tumor tissue and circulating DNA (ctDNA). Secondary objectives included assessing the roles of co-mutations and longitudinal changes in KRAS mutant copies concerning treatment response and survival outcomes. An external validation study confirmed the prognostic or predictive significance of co-mutations. Results: In the prospective cohort (n=24), patients with liver metastases exhibited significantly elevated ctDNA levels(p=0.01), while those with >3 metastatic sites showed increased Allele Frequency (AF) (P=0.002). Median overall survival (OS) was 7.5 months, progression-free survival (PFS) was 4.0 months, and the objective response rate (ORR) was 33.3%. Higher AF correlated with an increased risk of death (HR 1.04, p = 0.03), though not progression. Notably, a reduction in plasma DNA levels was significantly associated with objective response(p=0.01). In the retrospective cohort, KRAS and STK11 mutations co-occurred in 14/21 patients (p=0.053). STK11 mutations were independently detrimental to OS (HR 1.97, p=0.025) after adjusting for various factors. KRAS tissue AF did not correlate with OS or PFS. Within the validation dataset, STK11 mutations were significantly associated with an increased risk of death in univariate (HR 2.01, p<0.001) and multivariate models (HR 1.66, p=0.001) after adjustments. Conclusion: The RAS-Lung Project, employing innovative genotyping techniques, underscores the significance of comprehensive NSCLC genotyping. Tailored next-generation sequencing (NGS) and ctDNA monitoring may offer potential benefits in navigating the evolving landscape of KRAS-positive NSCLC treatment

    Analysis of efficacy and safety of CAR T-cell therapy in relapsed/refractory lymphomas: current indications and future perspectives

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    In the last few years, the introduction of chimeric antigen receptor (CAR) T-cell therapy into clinical practice has revolutionized the approach to patients with relapsed/refractory (R/R) large B-cell lymphoma (LBCL), whose outcome used to be dismal with median overall survival (OS) of approximately 6 months with standard salvage therapy. At our Institute, we started treating diffuse large B-cell lymphoma (DLBCL) patients with CAR T-cell products in August 2019 and they received either axicabtagene ciloleucel (axi-cel) and tisagenlecleucel (tisa-cel) as per regulatory indications. This research project presents the 2-year follow-up of the first 53 treated patients. Our first aim is to investigate the feasibility of this treatment strategy in a real-world setting, although the reimbursement criteria set by the Italian Medicines Agency (Agenzia Italiana del Farmaco, AIFA) are very similar to the inclusion criteria of clinical trials and stricter than those established by the regulatory authorities of many foreign countries. One month after infusion, the ORR was 66% with 19 patients already in CR (38%). Restaging at 3, 6 and 12 months post-infusion shows that early CRs tend to be maintained over time and, moreover, that a considerable number of PRs and a few SDs can improve into a CR. The safety data were consistent with what is reported in the literature; toxicity was generally manageable, largely due to the increasing expertise in handling the specific adverse events related to CAR T-cell therapy. Our results confirms that CAR T-cell therapy is both safe and effective in a real-life setting and that it represents a crucial weapon in a subset of patients who were previously doomed to an inevitably severe prognosis

    Language policies in a multilingual context: a comparative analysis between Italy and China

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    Questa ricerca ha l’obiettivo di confrontare le politiche linguistiche in Italia e in Cina, due Paesi multilingue, con particolare attenzione alla legislazione riguardante le lingue comuni. Nella prima parte della tesi viene descritta e confrontata la situazione sociolinguista dei due Paesi, dal punto di vista sia diacronico sia sincronico, permettendo così di tracciare un quadro generale della panoramica sociolinguistica, la quale costituisce il fondamento per analizzare le politiche linguistiche adottate. La seconda parte della tesi descrive e analizza rispettivamente la legislazione linguistica sulla lingua comune dei due Paesi, mostrando la diversità e le caratteristiche delle pratiche legislative di Cina e Italia su questo tema. L’ultima parte della tesi presenta un confronto tra le legislazioni linguistiche sulle lingue comuni da diverse prospettive, individuando e discutendo differenze e punti in comune. La tesi si conclude con un’analisi delle motivazioni che spingono la Cina e l’Italia ad adottare scelte differenti, mettendo in luce la diversità delle politiche linguistiche e la complessità dei fattori che le determinano.This research aims to compare language policies in Italy and China, two multilingual countries, with a particular focus on legislation concerning the common language. The first part of the thesis describes and compares the sociolinguistic situation in the two countries, from both a synchronic and a diachronic perspective, thus allowing for a general outline of the sociolinguistic overview, which is the foundation for analyzing the adopted language policies. The second part of the thesis describes and analyzes the language legislation concerning the common language in both countries, highlighting the diversity and characteristics of China's and Italy's legislative practices. The last part of the thesis presents a comparison of language legislations on common languages from various perspectives, identifying and discussing differences and commonalities. The thesis concludes with an analysis of the motivations driving China and Italy to make different choices, highlighting the diversity of language policies and the complexity of the factors that determine them

    Distributed and synchronized measurements for the wide-area observation of electric power systems in distorted and low-inertia conditions

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    With the aim of heading towards a more sustainable future, there has been a noticeable increase in the installation of Renewable Energy Sources (RES) in power systems in the latest years. Besides the evident environmental benefits, RES pose several technological challenges in terms of scheduling, operation, and control of transmission and distribution power networks. Therefore, it raised the necessity of developing smart grids, relying on suitable distributed measurement infrastructure, for instance, based on Phasor Measurement Units (PMUs). Not only are such devices able to estimate a phasor, but they can also provide time information which is essential for real-time monitoring. This Thesis falls within this context by analyzing the uncertainty requirements of PMUs in distribution and transmission applications. Concerning the latter, the reliability of PMU measurements during severe power system events is examined, whereas for the first, typical configurations of distribution networks are studied for the development of target uncertainties. The second part of the Thesis, instead, is dedicated to the application of PMUs in low-inertia power grids. The replacement of traditional synchronous machines with inertia-less RES is progressively reducing the overall system inertia, resulting in faster and more severe events. In this scenario, PMUs may play a vital role in spite of the fact that no standard requirements nor target uncertainties are yet available. This Thesis deeply investigates PMU-based applications, by proposing a new inertia index relying only on local measurements and evaluating their reliability in low-inertia scenarios. It also develops possible uncertainty intervals based on the electrical instrumentation currently used in power systems and assesses the interoperability with other devices before and after contingency events

    Diffusing alpha particles radiation treatment optimization in clinical settings

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    Alpha-particle emitters, notably used in 224Ra-DaRT, have emerged as effective in overcoming radiation resistance and providing targeted cancer therapy. These emitters cause DNA double-strand breaks, visualizable in human lymphocytes. The 224Ra DaRT technique, using a decay chain from seeds, extends alpha particle range, achieving complete tumor destruction while sparing healthy tissue. This thesis examines a biokinetic model, validated with patient data, and a feasibility study on skin squamous cell carcinomas are discussed. The study reports 75% tumor complete response rate and 48% patients experiencing acute grade 2 toxicity, resolving within a month. An observed abscopal effect (AE), where tumor regression occurs at non-irradiated sites, is examined, highlighting DaRT's potential in triggering anti-tumor immune responses. This effect, coupled with DaRT's high-linear energy transfer (LET), suggests its superiority over low-LET radiation in certain clinical scenarios. Improvements to DaRT, including the use of an external radio-opaque template for treatment planning, are explored. This advancement aids in determining source numbers for optimal tumor coverage, enhancing DaRT’s safety. The thesis outlines a typical DaRT procedure, from tumor measurements to source assessment and administration, emphasizing the importance of precise seed positioning. Furthermore, the thesis discusses DaRT's potential in treating prostate cancer, a prevalent global health issue, by offering an alternative to traditional salvage therapies. DaRT seeds, delivering alpha particle-based interstitial radiation, require precision in seed insertion due to their limited tissue range. In conclusion, the thesis advocates for DaRT's role in treating solid tumors, emphasizing its improved radiobiological potency and potential benefits over beta and gamma source-based therapies. Ongoing studies are assessing DaRT's feasibility in treating various solid tumors, including pancreatic, breast, prostate, and vulvar malignancies, suggesting a promising future in cancer treatment

    Directly training spiking neural networks for cyber-physical systems: from supervised to reinforcement learning

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    Spiking Neural Networks (SNNs) are bio-inspired Artificial Neural Networks (ANNs) utilizing discrete spiking signals, akin to neuron communication in the brain, making them ideal for real-time and energy-efficient Cyber-Physical Systems (CPSs). This thesis explores their potential in Structural Health Monitoring (SHM), leveraging low-cost MEMS accelerometers for early damage detection in motorway bridges. The study focuses on Long Short-Term SNNs (LSNNs), although their complex learning processes pose challenges. Comparing LSNNs with other ANN models and training algorithms for SHM, findings indicate LSNNs' effectiveness in damage identification, comparable to ANNs trained using traditional methods. Additionally, an optimized embedded LSNN implementation demonstrates a 54% reduction in execution time, but with longer pre-processing due to spike-based encoding. Furthermore, SNNs are applied in UAV obstacle avoidance, trained directly using a Reinforcement Learning (RL) algorithm with event-based input from a Dynamic Vision Sensor (DVS). Performance evaluation against Convolutional Neural Networks (CNNs) highlights SNNs' superior energy efficiency, showing a 6x decrease in energy consumption. The study also investigates embedded SNN implementations' latency and throughput in real-world deployments, emphasizing their potential for energy-efficient monitoring systems. This research contributes to advancing SHM and UAV obstacle avoidance through SNNs' efficient information processing and decision-making capabilities within CPS domains

    Prediction of the outcome of external cephalic version for breech presentation using the breech progression angle

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    Introduzione: La presentazione podalica complica il 3-4% delle gravidanze singole a termine. Sebbene il parto vaginale sia possibile, gli studi in letteratura hanno riportato un aumento del rischio di mortalità e morbilità fetale. Di conseguenza nel mondo il numero di tagli cesarei eseguiti per presentazione podalica è alto. Il rivolgimento per manovre esterne (RME) è una procedura ostetrica sicura che permette il passaggio del feto dalla presentazione podalica a quella cefalica, riducendo il numero dei tagli cesarei. L’angolo di progressione della parte presentata (AoP) è un parametro ecografico descritto in letteratura per la valutazione della progressione della parte presentata attraverso il canale del parto ed è stato recentemente studiato nelle gravidanze con presentazione podalica del feto. Obiettivi: L’obiettivo primario è valutare la correlazione tra l’AoP e il successo del RME. L’obiettivo secondario è verificare se esiste correlazione tra parametri anamnestici ed ecografici e la riuscita del RME. Materiali e metodi: È stato condotto uno studio osservazione prospettico monocentrico, sono state reclutate previo consenso informato 54 pazienti afferenti presso l’Ospedale Maggiore di Bologna con gravidanza singola dopo le 36 settimane e feto in presentazione podalica tra gennaio 2020 e giugno 2023. Risultati: La percentuale di RME riusciti è stata del 48,2%, il 53,7% delle donne ha partorito mediante taglio cesareo. Non abbiamo trovato una correlazione tra AoP e successo del rivolgimento. Tra le altre variabili analizzate l’unica correlata al successo del RME è la quantità di liquido amniotico Conclusioni: Non abbiamo trovato una correlazione tra AOP e successo del RME. Come descritto in letteratura l’unico parametro ecografico che è risultato associato al successo del RME è la quantità di liquido amniotico. Dato il disegno dello studio e la scarsa numerosità del campione sono necessari ulteriori studi per confermare i risultati.Introduction: Breech presentation complicates 3-4% of single term pregnancies. Although vaginal delivery is possible, some studies reported an increased risk of fetal mortality and morbidity. Consequently, the number of cesarean deliveries for breech presentation is high. External cephalic version (ECV) is a safe obstetric procedure that allows the conversion from breech to cephalic presentation, reducing the number of cesarean sections. The angle of progression (AOP) is an ultrasound parameter for the evaluation of the descent of the fetal head during labor and has recently been investigated in pregnancies with a breech presentation. Objectives: to evaluate the correlation between the AOP and the success of the ECV. The secondary objective is to verify if there is a correlation between anamnestic and ultrasound parameters and the success of ECV. Materials and methods: monocentric prospective observational study was performed including 54 patients with single pregnancy and fetal breech presentation at term who underwent to ECV at the Maggiore Hospital of Bologna between January 2020 and June 2023. Results: No correlation between AOP and success of the ECV was found. The only variable correlated to the success of the ECV was the amount of amniotic fluid. Conclusions: We have not found a correlation between AOP and success of the ECV. As previously stated in literature, the only ultrasound parameter associated with a successful ECV is the amount of amniotic fluid

    The european citizens' initiative: an analysis of its effectiveness as a tool for participatory democracy

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    Fin dalla sua attuazione nel 2012, l'Iniziativa dei cittadini europei (ICE) ha catturato l'attenzione di accademici e politici per il suo apparente potenziale come strumento di democrazia partecipativa in grado di promuovere il coinvolgimento diretto dei cittadini nel processo decisionale dell'UE. Tuttavia, dopo il suo lancio, questo strumento sembra aver deluso le speranze e le aspettative riposte in esso e, invece di fungere da ponte tra i cittadini e le istituzioni dell'UE, sembra essere diventato una chiara prova della leadership burocratica dell'UE a Bruxelles. Con la riforma della sua legislazione di attuazione, le istituzioni europee hanno voluto dare all'ICE un'altra possibilità di raggiungere il suo pieno potenziale di democratizzazione. A tre anni dall'entrata in vigore del nuovo Regolamento 2019/788 e a più di dieci anni dal suo inserimento nell'ordinamento giuridico europeo, riteniamo che sia il momento giusto per valutare il reale impatto dell'ICE nella promozione della democrazia partecipativa nell'UE. Per raggiungere questo obiettivo, la presente tesi di dottorato intraprende un'analisi completa di questa struttura di opportunità per la partecipazione dei cittadini, esplorando le sue origini, il suo quadro normativo, la sua applicazione pratica e le sue implicazioni per la democrazia europea attraverso un approccio interdisciplinare che combina l'uso di metodi sia qualitativi che quantitativi. Questa ricerca mira a fornire una comprensione più profonda e critica dell'ICE e del suo ruolo nella costruzione di un'Europa più partecipativa e più vicina ai cittadini.Since its implementation in 2012, the European Citizens' Initiative (ECI) has captured the attention of academics and politicians for its apparent potential as a participatory democracy tool that can promote direct citizen involvement in EU decision-making. However, since its launch, this tool seems to have dashed the hopes and expectations placed in it, and instead of serving as a bridge between citizens and EU institutions, it seems to have become a clear evidence of the EU's bureaucratic leadership in Brussels. By reforming its implementing legislation, the EU institutions wanted to give the ECI another chance to reach its full democratization potential. Three years after the entry into force of the new Regulation 2019/788 and more than a decade after its inclusion in the European legal system, we believe it is the right time to assess the real impact of the ECI in promoting participatory democracy in the EU. To achieve this goal, this dissertation undertakes a comprehensive analysis of this opportunity structure for citizen participation, exploring its origins, its regulatory framework, its practical application, and its implications for European democracy through an interdisciplinary approach that combines the use of both qualitative and quantitative methods. This research aims to provide a deeper and more critical understanding of the ECI and its role in building a more participatory and citizen-friendly Europe

    Retrospective assessment of fracture risk through opportunistic radiological screening in a large modern cohort of liver transplant recipients

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    Objective: Liver transplantation has been associated with a high prevalence of osteoporosis, although most data rely on single-center studies with limited sample size, with most of them dating back to late 1990s and early 2000s. The present thesis aims to assess the prevalence of fragility fractures and contributing factors in a large modern cohort of liver transplant recipients managed in a referral Italian Liver Transplant Center. Design and Methods: Paper and electronic medical records of 429 consecutive patients receiving liver transplantation from 1/1/2010 to 31/12/2015 were reviewed, and 366 patients were selected. Clinically obtained electronic radiological images within 6 months from the date of liver transplant surgery, such as lateral views of spine X-rays or CT abdominal scans, were opportunistically reviewed in a blinded fashion to screen for morphometric vertebral fractures. Clinical fragility fractures reported in the medical records, along with information on etiology of cirrhosis and biochemistries at the time of liver surgery were also recorded. Results: Prevalence of fragility fractures in the whole cohort was 155/366 (42.3%), with no significant differences between sexes. Of patients with fractures, most sustained vertebral fractures (145/155, 93.5%), the majority of which were mild or moderate wedges. Multiple vertebral fractures were common (41.3%). Fracture rates were similar across different etiologies of cirrhosis and were also comparable in patients with diabetes or exposed to glucocorticoids. Kidney function was significantly worse in women with fractures. Independent of age, sex, alcohol use, eGFR, etiology of liver disease, lower BMI was the only independent risk factor for fractures (adjusted OR 1,058, 95%CI 1,001-1,118, P=0.046) in this study population. Conclusions: A considerable fracture burden was shown in a large and modern cohort of liver transplant recipients. Given the remarkably high prevalence of fractures, a metabolic bone disease screening should be implemented in every patient awaiting liver transplantation

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