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The critical inquiry in humanities knowledge graphs: challenges, methods and innovations
Get PDFThis dissertation explores the challenges of representing humanities critical inquiries in Knowledge Graphs (KGs). Current KGs and online catalogues seem to flatten such an interpretative approach in the humanities. Additionally, they typically omit superseded theories rather than representing them with a weaker logical status (WLS). After defining the domain and its theoretical framework, the dissertation surveys existing methods for introducing claims in RDF (reification methods), examines how reification can convey a weaker logical status (expressing without asserting), and explores how existing ontologies formalise interpretations. Additionally, CH items in Wikidata have been systematically surveyed to determine annotators' habits and requirements, revealing poor usage of WLS claims and difficulty retrieving claims related to critical inquiry. Considering the strengths and weaknesses of existing reification methods, a new method, called Conjectures, which extends the RDF 1.1 syntax of Named Graphs, is proposed as a potential solution to include critical inquiries in CH KGs. The effectiveness and efficiency of Conjectures is assessed, demonstrating that it is competitive with existing reification methods. The representation is applied to a case study focusing on scholarly investigations into document authenticity. Specifically, the study examines the "Index of Medieval Documents Concerning the Upper Austrian Region that are Damaged, Tampered with, or Altered" by Siegfried Haider, which indexes the critical assessment of 153 historical documents. A data model and KG are produced and evaluated through a web application that integrates the claims into a prototypical online catalogue. The dissertation concludes by addressing the main research questions of the work and proposing some further developments on the work
Observations of fast radio bursts at low frequencies with the northern cross radio telescope
Get PDFThis thesis presents recent advancements in the study of fast radio bursts (FRBs)—short, energetic radio flashes of extragalactic origin with typical durations of a millisecond—through low-frequency observations primarily conducted with the Northern Cross radio telescope. A key focus is the investigation of the FRB–magnetar connection via long-term radio monitoring of a sample of nearby galaxies. While magnetars are among the most compelling progenitor candidates for FRBs, the fraction of the FRB population that can be attributed to magnetars similar to those observed in our Galaxy remains uncertain. The FRB population is generally classified into one-off events, which are detected only once, and repeating sources, which constitute approximately 7% of the known FRBs. However, it is still unclear whether these two categories represent distinct physical classes of sources. To address this question, this work includes observations at 408 MHz and 1.4 GHz of FRB 20220912A, one of the most active repeating FRBs known. These observations aim to characterize its energy distribution and spectro-temporal properties, providing insights into both the underlying FRB emission mechanism and the nature of the repeaters–one-off dichotomy. Furthermore, repeating FRBs offer the unique opportunity to achieve precise localizations with angular resolutions on the order of tens of milliarcseconds. This level of precision enables the association of an FRB with a specific environment within its host galaxy—such as a star-forming region, a galactic nucleus, or a stellar cluster—potentially revealing a persistent counterpart, a feature identified in only a few repeating FRBs to date. Finally, this thesis investigates how systematic uncertainties in the data calibration process of VLBI observations can impact the accuracy of FRB localizations, ultimately influencing their association with specific local environments
Neural compressed sensing for MRI and ECG data acquisition and compression
Get PDFBiomedical signal acquisition often occurs in resource-constrained environments, necessitating advanced encoding or acquisition algorithms. In such contexts, Compressed Sensing (CS) offers a promising solution but faces performance challenges, especially in practical implementations. This dissertation explores the integration of Neural Network and Compressed Sensing techniques for the efficient acquisition and compression of biomedical signals, specifically focusing on Electrocardiogram (ECG) and Magnetic Resonance Imaging (MRI) data. For ECG, two innovative approaches are presented. The first approach introduces a data-driven binary encoding to develop a lightweight encoding mechanism. The second approach introduces an adaptive, incremental compression scheme that uses a performance predictor to dynamically adjust the number of transmitted measurements. For MRI data acquisition, the work delves into advanced undersampling techniques. The first part builds on the state-of-the-art LOUPE architecture, incorporating CS-derived constraints into the training framework to improve the quality of reconstructed MRI images. The second part, introduces the concept of incremental acquisition, where the number of acquired k-space samples is dynamically adjusted based on real-time quality assessments. This dissertation demonstrates how combining model-based CS with data-driven DNN holds the potential to revolutionize acquisition methodologies for biomedical signals, making advanced diagnostics efficient even in resource-hungry settings
Pencil Beam Scanning Proton Therapy reirradiation for locally recurrent rectal cancer: clinical outcome, toxicity and dosimetric comparison from a single center experience
Get PDFPurpose: Treatment for locally recurrence rectal cancer is challenging. Reirradiation can be a curative or palliative treatment, and part of multi modality treatment. However, it presents risk of late complications given the radiation sensitivity of nearby organs and tissues of the abdomen and pelvis. The aim of the present study is to report the outcome and toxicity of reirradiation with Pencil Beam Scanning Proton Therapy (PBS-PT) for patients with locally recurrent rectal cancer. Methods and materials: a single-institution, retrospective analysis of 15 patients with history of pelvic radiotherapy for rectal cancer receiving PBS-PT for local recurrence was performed. Data on patient, treatment characteristics, outcomes and acute and late toxicity were collected. Dosimetrical comparison between Photon and Proton for challenging plans was done. Univariate analyses (UVA) of several factors for outcomes including FDG-PET/CT median maximum standardized uptake value (SUVmax), changes in Neutrophil/Lymphocytes ratio after PT was performed. Results: The median reirradiation dose was: 50 GyRBE (range 50,4-39,6 GyRBE). Two patients received concurrent chemotherapy. The 1-year local control, progression-free survival, and overall survival rates were 66.7%, 33,3%, 93,3% respectively. Acute grade >3 toxicity rate was 6,6%, while late grade >3 toxicity was 13,3%. At UVA Cox proportional hazards model analyses no one of the variables showed a significant difference in all outcomes. Dosimetrical comparison showed a substantial advantage in favor of PT for pre-sacral and sacral region of relapse. Conclusions: in our study PBS-PTfor locally recurrent rectal cancer demonstrated low acute toxicity rates and acceptable late toxicity supporting the use of PBS-PT as an option for this patient population
Treatment of Pectus Excavatum with taulinoplasty: a pilot study
Get PDFABSTRACT Introduzione: Questo studio ha l’obiettivo di introdurre la Taulinoplastica come tecnica chirurgica mini-invasiva per il trattamento del pectus excavatum, offrendo un’alternativa alle tecniche di Ravitch e Nuss. Gli obiettivi secondari includono la valutazione delle complicanze intra e postoperatorie e la soddisfazione dei pazienti in termini di dolore, risultato estetico e qualità della vita. Materiali e Metodi: Studio pilota prospettico monocentrico su 12 pazienti affetti da pectus excavatum. I criteri di inclusione erano un Indice di Haller >2,5 e un’età compresa tra 11 e 35 anni, con adeguata flessibilità toracica. Sono stati esclusi pazienti con gravi deformità spinali, malattie croniche, deficit cognitivi, gravidanza o allattamento. Lo studio si è articolato in una fase di selezione (HRTC con ricostruzione 3D della gabbia toracica, spirometria, ecocardiogramma), trattamento chirurgico e follow-up con TAC 3D a 12 mesi, RX a 24 e 36 mesi, intervista al paziente e rimozione del dispositivo dopo massimo 36 mesi. Risultati: Le complicanze postoperatorie includevano due deiscenze di ferita, una delle quali ha richiesto la rimozione del mezzo di sintesi. La degenza media è stata di 1,8 giorni. Il dolore postoperatorio, valutato tramite scala VAS e consumo di analgesici, è risultato ben controllato con paracetamolo orale per tre giorni. I questionari hanno confermato un’elevata soddisfazione dei pazienti in termini di qualità della vita e miglioramento delle attività quotidiane. Conclusioni: Nonostante il numero limitato di pazienti, la Taulinoplastica si è dimostrata una tecnica affidabile ed efficace, con risultati soddisfacenti dal punto di vista estetico e della gestione del dolore. Sono necessari studi con una casistica più ampia per una validazione definitiva.ABSTRACT Introduction: This study aims to introduce Taulinoplasty as a minimally invasive surgical option for pectus excavatum, offering an alternative to the Ravitch and Nuss techniques. Secondary objectives include evaluating intra- and postoperative complications and assessing patient satisfaction in terms of pain, aesthetics, and quality of life. Materials and Methods: A prospective, single-center pilot study was conducted on 12 patients with pectus excavatum. Inclusion criteria were a Haller index >2.5 and age between 11–35 years, provided sufficient thoracic flexibility. Exclusion criteria included severe spinal deformities, chronic diseases, cognitive impairments, and pregnancy or breastfeeding. The study included a selection phase (HRTC with 3D chest reconstruction, spirometry, echocardiography), surgical treatment, and follow-up with a 3D CT at 12 months, X-rays at 24 and 36 months, patient interviews, and device removal after a maximum of 36 months. Results: Postoperative complications included two cases of wound dehiscence, one requiring fixation device removal. The average hospital stay was 1.8 days. Pain, assessed via VAS and analgesic consumption, was well controlled with oral acetaminophen for three days. Patient questionnaires indicated high satisfaction in terms of quality of life and improved daily activities. Conclusions: Despite the limited sample size, Taulinoplasty appears to be a reliable and effective technique, providing satisfactory aesthetic and pain management outcomes. Further validation with a larger cohort is required
Drug and probiotics-based intervention strategies for the restoration of gut microbiome dysbiosis
Get PDFThe gut microbiota is a highly complex and intrinsically dynamic ecosystem that undergoes significant changes throughout an individual’s lifetime, influenced by various factors such as diet and lifestyle. Despite its adaptability, the microbiota's balance can be disrupted, leading to a dysbiotic state frequently associated with chronic non-communicable diseases (NCDs) such as obesity, diabetes and cancer. Addressing this imbalance is critical, and interventions such as novel bioactive compounds and next-generation probiotics offer promising avenues for restoring microbial homeostasis. This thesis presents two studies focusing on drug- and probiotics-based strategies aimed at re-establishing eubiosis within the gut microbiota. The first study evaluated the efficacy of four novel compounds in vitro using the Batch Gut Model Cultures assay, specifically targeting antibiotic-resistant Clostridioides difficile. Results demonstrated that certain compounds effectively reduced the target pathogen while enhancing gut microbial diversity. Moreover, the Batch Gut Model Cultures assay proved to be both time- and resource- efficient, retaining robust methodological effectiveness. The second study investigated the impact of an ad hoc microbial consortium as next- generation probiotics on mitigating early weaning effects using an in vivo murine model. Early weaning, increasingly common in Western countries, is recognized as a contributing factor to the onset of numerous NCDs. Findings revealed that this microbial intervention reduced local and systemic inflammation while promoting beneficial bacterial taxa (e.g., Lactobacillus) in the murine gut. Furthermore, the study underscores the utility of this approach as a mouse model for early weaning, addressing the current lack of research linking gut microbiota dynamics to early weaning outcomes. In conclusion, these studies provided foundational insights into the potential of in vitro and in vivo approaches to assess the restoration of gut eubiosis. They could pave the way for future research to further explore innovative strategies to address the dysbiotic layout and its associated health challenges
Three essays in empirical macroeconomics
Get PDFThis thesis presents three empirical contributions on relevant topics for monetary policy in the Euro Area. In the first chapter, I study macroeconomic tail risks in the EA by constructing conditional distributions of expected GDP growth and inflation and estimating the GDP-at-risk and the Inflation-at-risk. The time variance of the tails differs considerably, and asymmetries in the balance of risks are accompanied by a weak synchrony of GDP-at-risk estimates between member states, especially during crises; upside risks to inflation appear more synchronous. Results have mixed implications for monetary policy, as the weak synchrony of business cycles during crises indicates a possible failure of a criterion for optimal currency areas; on the contrary, the coordination of upside risks to prices is an enhancing factor for a common monetary policy. In the second chapter, I investigate the evolution of the natural rate (r*) in the EA in the last twenty-five years. The estimation of r* is performed by extracting the trend component of real rates from the risk-free yield curve, finding a marked drop around the Great Financial Crisis and a partial recovery after 2021. The r* trend is decomposed into two components, capturing “quantity” imbalances between savings and investments and “quality” effects concerning the availability of safe assets, finding the former to be main driver of r*. In the third chapter, I study the heterogeneity of monetary policy transmission to financial markets, focusing on the reaction of high-ESG stocks in the EA. The analysis combines a study at stock level and one on portfolios constructed by assuming different degrees of ESG-awareness. Results hint at a stronger sensitivity of high-ESG stocks and portfolios to MP shocks, particularly for securities issued by financial companies, and suggest that the price of these assets can be particularly sensitive to unexpected events in the financial markets
Pediatric pulmonary arterial hypertension: characteristics and efficacy of specific therapy on clinical, echocardiographic and hemodynamic parameters
Get PDFPulmonary arterial hypertension (PAH) in children has peculiar features and require a unique approach. This study describes the epidemiological features of pediatric PAH patients followed in a referral center and investigates the effects of PAH-targeted drugs. Data from consecutive pediatric PAH patients referred to our center from 1980 to 2024 were collected. Of 137 patients, 60 (44%) had idiopathic/hereditary PAH (I/HPAH) and 60 (44%) had PAH associated with congenital heart disease (PAH-CHD). PAH-CHD patients were slightly younger than I/HPAH at diagnosis and there was not a female predominance. When considering treatment strategy, among IPAH, 14 (23%) patients showed a positive response to acute vasoreactivity test at diagnosis and were treated with calcium-channel blocker, but only 3 (5%) were long-term responders. Excluding acute responders, compared to PAH-CHD, I/H PAH patients were usually treated with a more aggressive strategy. Treatment strategy efficacy was confirmed by a significant improvement in symptoms, in exercise capacity, in echocardiographic parameters and in hemodynamics with a significant increase in cardiac index, in values of pulmonary artery oxygen saturation and reduction in pulmonary vascular resistance index. In conclusion, this series confirms a different distribution of pediatric PAH etiologies compared to adults, with children having a greater predominance of I/HPAH and PAH-CHD. In children with I/HPAH, treatment strategy is similar to adults with rapid sequential or upfront oral combination therapy if lower risk and initial parenteral combination therapy if high risk. In PAH-CHD, treatment strategy is characterized by a more prudential approach with first-line monotherapy and combination therapy in case of inadequate response. Beyond hemodynamics, PAH-targeted drugs’ effects are demonstrated by a significant improvement in symptoms, exercise capacity and right ventricle echocardiographic parameters suggesting a role of this non-invasive and easily available tools in monitoring disease progression and treatment response
The impact of environmental contaminants on human DNA methylation variability: the Italian case of Bussi sul Tirino
Get PDFDNA methylation (DNAm) is an epigenetic mechanism that regulates gene expression and contributes to biological plasticity. An extensive scientific literature has demonstrated the potential of contaminants to alter DNAm profiles, resulting in impacts on human biology and health, especially in terms of reproductive health, biological ageing and neurological diseases. This thesis focuses on a case study of national relevance: the Site of National Interest (SIN) of Bussi sul Tirino (Abruzzo, Italy), an area contaminated by the illegal disposal of industrial waste in soil and groundwater. The central hypothesis is that long-term exposure to pollutants may influence DNAm variability and the health of local residents. To test this hypothesis, buccal swabs were collected from 61 individuals, divided into two groups according to level of exposure. In a subgroup of 33 individuals, DNAm and genetic variation were assessed using Illumina MethylationEPIC (850k) and HumanOmniExpress (720k) arrays, respectively. In addition, DNAm levels of three repetitive elements (LINE-1, Alu, rDNA) were measured in all 61 samples by bisulfite sequencing. Two age- and sex-adjusted linear models revealed 622 CpGs with differential DNAm levels (DMPs) between the two groups associated with different biological pathways and 1,138 CpGs with differential variability and convergence to similar DNAm values in the high-exposure group. The meQTL analysis conducted on the 622 DMPs indicated that these differences were not genetically driven, implicating environmental exposure as the main factor. There were no significant differences between the two groups in the number of epimutations, epigenetic lesions, and epigenetic aging. However, the hypomethylation of LINE-1 found in the high-exposure group suggested a possible role of pollutants in conferring genomic instability and contributing to the onset of certain diseases. Finally, the thesis presents two preliminary studies on DNA for tracking contaminants in groundwater and the role of genetic variability in detoxification from atmospheric contaminants, respectively
Luminescence-based techniques for water quality monitoring
No full textWater quality monitoring is a key aspect for providing and maintaining clean water supplies for the whole world. Water pollutants are many and heterogeneous in chemical nature so numerous sensing techniques and platforms are needed to provide a comprehensive analysis of water samples. In this context, sensors with an optical signal transduction mechanism can provide numerous advantages such as cost-effectiveness, ease of use, and rapid outputs. This PhD thesis describes three different approaches for the sensing of polluting chemical species relevant to water quality, employing luminescent based techniques. Detection of nonsteroidal anti-inflammatory drugs (NSAIDs), representing the category of “emerging pollutants”, was performed employing supramolecular fluorescent sensors capable of binging NSAIDs via hydrogen bonds and hydrophobic interactions in organic medium. Two different sets of sensors were developed, characterized and tested against common NSAIDs. Luminescent Eu(III) metal complexes were used to sense inorganic anionic species relevant to water quality monitoring. The peculiar photophysical properties of Eu(III) allowed us to obtain different outputs to different analytes; moreover, the high Lewis acidity of Eu(III) made the complexes able to bind anions in aqueous environment. An electrochemiluminescence-based immunosensor for the detection of Listeria was developed - in collaboration with Diatheva s.r.l. - as proof of concept, employing the architecture of an already existing immunoassay, to see how the assay’s performances could be enhanced, with minimal changes to the design. The architecture of the assay was adapted from a commercial ELISA developed by Diatheva and modified to be used in ECL, with the aid of magnetic micro-beads technology, obtaining promising results. Overall, this thesis presented valid optical-based sensing techniques applicable to environmental water quality monitoring. Moreover, this work represents a promising advancement in the field of sensing techniques development