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A Single-center comparative analysis of sternotomy and minimally-invasive approach to mitral valve surgery: evaluating outcomes and healthcare resource implications
Get PDFThis thesis presents a single-center comparative analysis of sternotomy (STER) and minimally invasive minithoracotomy (MTH) approaches in mitral valve surgery. The study included 1,184 patients who underwent mitral valve surgery between January 2004 and December 2022. The primary objective was to assess differences in mortality, morbidity, and long-term survival between the two approaches. Secondary objectives included evaluating the impact on operative time, blood loss, and length of hospital stay. The study found that MTH was associated with a lower incidence of in-hospital mortality and a shorter intensive care unit stay. However, there was no significant difference in the overall length of hospital stay between the two groups. Long-term follow-up revealed a lower mortality rate and a reduced need for reoperation in the MTH group. The thesis concludes that MTH offers several advantages over STER, including reduced mortality, morbidity, and reoperation rates. However, the study acknowledges limitations due to its single-center retrospective design and the relatively small number of MTH cases. Despite these limitations, the findings suggest that MTH is a safe and effective alternative to STER for selected patients undergoing mitral valve surgery
Towards a sustainable and healthy use of fishery resources: processes, technologies, nutritional quality and contaminants
Get PDFWith a direct impact on global food security and public health and providing essential nutrients to billions of people, seafood safety is a major concern in today's world. Contaminants such as microplastics, heavy metals, other chemicals and even preservation issues are increasingly jeopardizing the quality of seafood, posing a risk to both marine ecosystems and human consumers. Ensuring safe and sustainable seafood is the key to protecting both the environment and human well-being in the face of these growing challenges.
This dissertation explores sustainable approaches to the use of seafood, focusing on seafood safety, nutritional quality and environmental impact.
In the context of environmental challenges, the study highlights the increasing presence of microplastics and chemical contaminants in some seafood products, identifying their physiological effects on key species and the associated health risks to human consumers. Additionally, the study assesses the efficacy of technological advancements in seafood preservation, with particular emphasis on modified atmosphere packaging (MAP) and rapid freezing techniques as means for reducing the use of chemical additives while maintaining high product quality. These post-harvest technologies play a key role in preserving nutritional composition and ensuring safety along the supply chain.
This work addresses the sustainable use of fisheries and aquaculture resources from a holistic point of view, using seafood valorisation as a lever to compensate for the decline in fishery resources (and fishermen's profits). It provides ideas and explores innovative strategies for better preserving seafood products within the context of a growing global demand for safe and sustainable seafood
Biomechanical and biological prognostic factors influencing clinical and functional outcomes in patients with knee instability and anterior cruciate ligament lesion
Get PDFObiettivo: La lesione del legamento crociato anteriore (LCA) è una delle più comuni negli sportivi, e la sua ricostruzione rappresenta una delle procedure ortopediche più frequente. Tuttavia, il tasso di successo non è ancora del 100%. Questo progetto di ricerca mira a identificare i fattori biomeccanici e biologici che influenzano gli esiti clinici e funzionali nei pazienti con lesione del LCA. Metodi: Sono stati valutati in un primo studio biomeccanico 326 pazienti con lesione del LCA. Prima dell'intervento chirurgico, i test di Lachman e pivot shift sono stati eseguiti utilizzando un accelerometro assiale per quantificare l'impatto delle lesioni meniscali sulla lassità del ginocchio. In un secondo studio, 30 pazienti asintomatici, precedentemente sottoposti a ricostruzione del LCA, sono stati valutati mediante termografia a infrarossi per confrontare la temperatura del ginocchio operato con quello controlaterale sano. Risultati: Nello studio biomeccanico, la traslazione tibiale anteriore (test di Lachman) è risultata significativamente maggiore nei pazienti con lesioni meniscali mediali (7,3±1,7 mm, p=0,049) o con lesioni meniscali mediali e laterali (7,7±1,6 mm, p=0,001) rispetto ai pazienti senza lesioni meniscali (6,7±1,3 mm). Nello studio sulla termografia, la temperatura media era più alta (p=0,010) per il ginocchio operato (31,4±1,4 °C) rispetto a quello sano (31,1±1,6 °C), con differenze accentuate nei pazienti sottoposti a trattamento meniscale concomitante. Conclusione: Questo progetto ha dimostrato che le lesioni meniscali contribuiscono significativamente alla lassità del ginocchio nei pazienti con lesione del LCA. Inoltre, la termografia ha rivelato uno stato infiammatorio persistente anni dopo l'intervento, suggerendo un potenziale rischio di degenerazione articolare precoce.Objective: Anterior cruciate ligament (ACL) injury is one of the most common injuries among athletes, and its reconstruction is one of the most frequently performed orthopedic procedures. However, the success rate is not yet 100%. This research project aims to identify the biomechanical and biological factors influencing clinical and functional outcomes in patients with ACL injury. Methods: In a first biomechanical study, 326 patients with ACL injury were evaluated. Before surgery, Lachman and Pivot Shift tests were performed using an axial accelerometer to quantify the impact of concomitant meniscal injuries on knee laxity. In a second study, 30 asymptomatic patients who had previously undergone ACL reconstruction were assessed using infrared thermography to compare the temperature of the operated knee with the contralateral healthy knee. Results: In the biomechanical study, anterior tibial translation (Lachman test) was significantly higher in patients with medial meniscal injuries (7.3 ± 1.7 mm, p = 0.049) or both medial and lateral meniscal injuries (7.7 ± 1.6 mm, p = 0.001) compared to those without meniscal injuries (6.7 ± 1.3 mm). In the thermography study, the mean temperature was significantly higher (p = 0.010) in the operated knee (31.4 ± 1.4 °C) compared to the healthy knee (31.1 ± 1.6 °C), with greater differences in patients who had undergone concomitant meniscal treatment. Conclusion: This project demonstrated that concomitant meniscal injuries significantly contribute to knee laxity in patients with ACL injury. Additionally, thermography revealed a persistent inflammatory state years after surgery, suggesting a potential risk for early joint degeneration
Additive manufacturing technology in the production of joint prosthetic implants: long-term outcome of porous cups produced from titanium powders
Get PDFIntroduzione: Questa tesi indaga l'applicazione della tecnologia Additive Manufacturing nella produzione di impianti protesici articolari, focalizzandosi sugli esiti a lungo termine dei cotili porosi di ultima generazione realizzati con polveri di titanio. La prima parte del lavoro analizza la tecnologia Additive Manufacturing, evidenziando i suoi vantaggi e svantaggi. Nella seconda parte, si propone un excursus storico sulle coppe acetabolari impiegate nella chirurgia protesica primaria dell’anca. Infine, la terza parte presenta un'analisi basata su dati di registro, che valuta la sopravvivenza degli impianti protesici in un ampio campione di pazienti a lungo termine. Questa tesi contribuisce ad una maggiore comprensione dell'Additive Manufacturing nel contesto ortopedico e pone le basi per future ricerche orientate al miglioramento e alla personalizzazione degli impianti protesici. Materiali e Metodi: Sono stati analizzati solo i cotili non cementati più frequentemente impiantati (>200 impianti), suddividendoli in tre gruppi in base al materiale e al rivestimento superficiale: cotili ultraporosi in titanio stampati in 3D (I), cotili ultraporosi rivestiti in tantalio o titanio di terza generazione (II) e cotili di seconda generazione (III). Sono stati inclusi un totale di 15.737 cotili: 9.862 (62,7%) nel gruppo I, 2.067 (13,1%) nel gruppo II e 3.808 (24,2%) nel gruppo III. Risultati: I tre gruppi hanno mostrato tassi di sopravvivenza complessivi a 10 anni comparabili (p = 0,62). All'interno dei gruppi I e II, i tassi di sopravvivenza dei diversi modelli protesici sono sovrapponibili (p = 0,86 e p = 0,31), mentre il gruppo III ha mostrato differenze statisticamente significative al suo interno (p = 0,004. Conclusioni: I cotili ultraporosi stampati in 3D mediante tecnologia Additive Manufacturing hanno dimostrato risultati a 10 anni equivalenti a quelli dei cotili ultraporosi di terza generazione prodotti con tecniche convenzionali e quelli di seconda generazione, senza un aumento del rischio di mobilizzazione asettica ed infezione.Introduction: This thesis investigates the application of Additive Manufacturing (AM) technology in the production of joint prostheses, focusing on the long-term outcomes of next-generation porous acetabular cups made from titanium powders. The first part of the work analyzes AM technology, highlighting its advantages and disadvantages. The second part provides a historical overview of acetabular cups used in primary hip arthroplasty. Finally, the third part presents an analysis based on registry data, assessing the long-term survival of prosthetic implants in a large patient sample. This thesis contributes to a better understanding of Additive Manufacturing in the orthopedic field and lays the groundwork for future research aimed at improving and customizing prosthetic implants. Materials and Methods: Only the most frequently implanted uncemented acetabular cups (>200 implants) were analyzed, dividing them into three groups based on the material and surface coating: 3D-printed titanium ultraporous acetabular cups (Group I), third-generation titanium or tantalum-coated ultraporous acetabular cups (Group II), and second-generation acetabular cups (Group III). A total of 15,737 acetabular cups were included: 9,862 (62.7%) in Group I, 2,067 (13.1%) in Group II, and 3,808 (24.2%) in Group III. Results: The three groups showed comparable overall 10-year survival rates (p = 0.62). Within Groups I and II, the survival rates of different prosthetic models were similar (p = 0.86 and p = 0.31), while Group III showed statistically significant differences within itself (p = 0.004). Conclusions: 3D-printed ultraporous acetabular cups made with Additive Manufacturing technology demonstrated 10-year results equivalent to those of third-generation ultraporous cups produced with conventional techniques and second-generation cups, with no increased risk of aseptic loosening or infection
The educational space
Get PDFQuesta ricerca esplora il ruolo dell'educazione motoria e del gioco tradizionale nello sviluppo socio-culturale e fisico dei bambini. Lo studio si basa sull’applicazione della Prasseologia motoria, un quadro teorico che analizza il comportamento motorio sia attraverso la logica interna dell'attività sia attraverso le influenze socioculturali esterne. Seguendo il modello di Pierre Parlebas, la ricerca evidenzia come le attività motorie modellino il comportamento individuale, le interazioni e l’espressione personale.
La ricerca empirica è stata condotta attraverso un approccio misto (Mixed Methods), combinando metodologie quantitative (questionari) e qualitative (focus group). Il campione di studio ha coinvolto tre scuole primarie e 15 classi, in cui gli studenti hanno partecipato a dieci sessioni strutturate di educazione motoria. Le attività includevano esercizi psicomotori, giochi cooperativi, competizioni individuali e attività miste, svolte sia in ambienti indoor che outdoor.
I risultati evidenziano come le attività all’aperto favoriscano una maggiore interazione sociale, coinvolgimento emotivo e adattabilità rispetto ai giochi strutturati in ambienti chiusi. L’analisi dei dati, condotta attraverso il Differenziale Semantico di Osgood, ha rivelato che gli studenti attribuiscono un valore sociale più alto e una maggiore percezione di empowerment alle attività cooperative e psicomotorie rispetto alle competizioni individuali. Inoltre, gli ambienti esterni risultano più stimolanti e migliorano il benessere psicofisico, confermando il valore educativo del gioco motorio oltre le strutture sportive tradizionali.
Questi risultati supportano l’integrazione dei principi della Prasseologia motoria nei curricoli scolastici, promuovendo un approccio olistico all’apprendimento basato sul movimento. Favorire esperienze motorie diversificate consente di sviluppare autonomia, espressione di sé e coesione sociale, contribuendo alla crescita personale e cognitiva degli studenti.
Questa ricerca sottolinea l'importanza di ripensare l’educazione motoria oltre lo sport, adottando un modello più inclusivo, partecipativo e centrato sul bambino, in cui il gioco e il movimento siano valorizzati come strumenti fondamentali per l’apprendimento e lo sviluppoThis dissertation explores the role of motor education and traditional play in fostering children's socio-cultural and physical development. The research focuses on the application of Motor Praxeology, a theoretical framework that examines motor conduct through both intrinsic activity logic and external socio-cultural influences. Drawing upon the works of Pierre Parlebas, the study highlights how movement-based activities shape individual behavior, interaction, and personal expression.
The empirical research was conducted through a Mixed Methods approach, integrating both quantitative (questionnaires) and qualitative (focus groups) methodologies. The study involved three primary schools and 15 classes, where students participated in ten structured physical education sessions. The activities included psychomotor exercises, cooperative games, individual competitions, and mixed activities, all performed in both indoor and outdoor settings.
Key findings indicate that outdoor activities enhance social interaction, emotional engagement, and adaptability in comparison to structured indoor games. The data, analyzed through the Semantic Differential of Osgood, reveal that students perceive greater social value and personal empowerment in cooperative and psychomotor activities rather than competitive individual challenges. Furthermore, outdoor settings appear to foster higher engagement and well-being, reinforcing the educational value of motor play beyond traditional sports structures.
These results support the integration of Motor Praxeology principles into educational curricula to foster a more holistic approach to movement-based learning. By emphasizing diverse movement experiences, educators can cultivate self-expression, autonomy, and social cohesion, ultimately contributing to students' personal and cognitive development.
This research underscores the importance of rethinking physical education beyond sport, advocating for a broader, inclusive, and child-centered approach that values traditional play and movement-based learning in contemporary educational contexts
Assessment of bias and uncertainty of species occurrence data: metrics and methods
Get PDFThe increasing availability of large quantities of data on species occurrence (i.e., presence and/or presence and absence of species) to support biodiversity studies and conservation actions is not always coupled with the data quality. Indeed, species occurrence data can present forms of bias (i.e., systematic deviation from the true value) and uncertainty (i.e., dispersion of values or lack of knowledge). In the PhD thesis, I evaluated different metrics and methods to address uncertainty and bias of species occurrence data.
In the first chapter, the effect of the sampling method of the presences and absences and the effect of their ratio (i.e., sample prevalence) were tested on different Species Distribution Models: Favourability and Probability-based SDMs. In the second and third chapters, I employed various metrics to evaluate the quality of species occurrence data stored in a case study database, namely the sPlotOpen database. The taxonomic, spatial and temporal bias were measured at European and habitat levels respectively with i) the completeness of the species richness, ii) the Nearest Neighbor Index, iii) the Pielou's index. Besides, the temporal uncertainty—defined as the information decay of the species occurrence over time—was quantified using a negative exponential function.
Among the main results, I found that the sampling methods (i.e., random and stratified sampling) of the species occurrences had no effect on the performance of the Favourability and Probability models. The Favourability model, in contrast, exhibited lower variability and only slightly higher accuracy than Probability in the predictions of species distribution. Moreover, the metrics used to assess the dimensions of bias in species occurrence data proved to be effective, revealing heterogeneous patterns. Additionally, the analysis of temporal uncertainty identified hotspot areas across Europe. Results that highlighted the necessity of assessing data quality prior to its use in biodiversity inferences
Characterization of a cold atmospheric plasma generated by a custom-design dielectric barrier discharge reactor for bioaerosol decontamination
Get PDFCold Atmospheric Plasma (CAP) based technology represents a promising approach for bioaerosols decontamination. CAPs generates a mixture of ions, electrons, and reactive species at room temperature, which in contact with the bioaerosols lead to the inactivation of microorganisms through cell membrane disruption and oxidative stress. Studies have shown that CAPs are effective in reducing airborne bacteria, viruses, and fungal spores. Nevertheless, few studies focus on plasma reactors optimization. In this context, the development of a new CAP reactor, named GAPS - Grid-like Air Plasma Sanitizer, could represents a promising advancement in these field. This study presents the design, development, and characterization of GAPS, specifically engineered for continuous bioaerosol treatment. The research aimed to enhance the interaction between GAPS and bioaerosols to maximize inactivation efficiency. Computational Fluid Dynamics (CFD) simulations provided essential insights into airflow patterns, ensuring uniform bioaerosol distribution within the reactor chamber and effective plasma interaction with the airflow. At full capacity, the operating specific power was found to be 0.014 W/cm^{2}. Chemical analysis of the plasma environment, conducted using Fourier-transform infrared (FTIR) spectroscopy, identified the generation of reactive oxygen and nitrogen species (RONS). Specifically, GAPS produced approximately 9 ppb of and less than 2 ppm for when the system reached steady-state conditions. The CAP DBD reactor's biological efficacy was validated through the CFU counting method, which determined a 4-log reduction of aerosolized non-pathogenic Escherichia Coli, a well-known representative gram-negative bacteria. Notably, the reactor's Electrical Energy per Order (EEO) was measured to be of 2x10^{-4} kWh/m^{3} per order, two order of magnitude lower than other plasma-based air sanitization devices found in literature. While these results are promising, several challenges remain. Variability in bioaerosol composition and environmental conditions may affect disinfection efficacy, highlighting the need for further research to optimize reactor performance across different scenarios
Digital 3D reconstruction as a research environment in art and architecture history. Infrastructure for documentation and publication.
Get PDFThis dissertation addresses the still unsolved challenges concerning digital 3D reconstruction, particularly its documentation, publication, and representation in archaeology, art, and architectural history. An effort is being made to create an open-access 3D model repository that meets modern documentation and publication requirements. The practical usability of this platform will be examined in the context of higher education, as well as in scientific and cultural fields. The digital turn in the sciences and humanities has enabled the reclamation of lost Cultural Heritage and the visualisation of never-built architectural and urban projects through digital 3D models. Source-based hypothetical 3D reconstructions offer a way to investigate historical buildings and present research results visually. However, this shift has also introduced challenges related to the management of vast amounts of heterogeneous digital data. The lack of standards for documenting and publishing 3D reconstructions has led to knowledge loss, outdated and unreadable data, and difficulties in long-term preservation. Existing guidelines have attempted to establish principles for documentation, accessibility, and readability. However, the community still struggles to enforce these due to the absence of well-established solutions. Limited funding and the need for advanced digital documentation methods based on information technology further complicate compliance with these recommendations.
This research examines documentation methods at different stages of a digital asset’s life cycle, focusing on model creation, publication, and reuse. The study aims to systematise modelling techniques, metadata schemas, and publication strategies to ensure sustainable access to digital heritage models. The ultimate goal is to create a structured infrastructure that supports documentation and publication based on widely accepted standards while facilitating accessibility for a broad audience
Anomaly detection challenges in monitoring applications
Get PDFMonitoring physical systems has become pervasive, particularly in critical applications where ensuring operational integrity is paramount. A fundamental task in this context is identifying anomalous behaviors, commonly referred to as anomaly detection. Over the past years, significant attention has been devoted to anomaly detection, leading to the development of more accurate and robust algorithms capable of processing complex data. However, several fundamental challenges remain. Firstly, anomaly detection is inherently unsupervised, making it difficult to exploit prior knowledge about possible anomalies during the design phase. Secondly, despite advances in related fields, anomaly detection has not been thoroughly analyzed from an information-theoretic perspective. This lack of exploration complicates its integration with other well-established tasks, such as signal compression. This dissertation aims to address these challenges by presenting both practical and information-theoretic frameworks for anomaly detection. In the first part, we design a tool designed to mitigate the challenge of evaluating anomaly detection performance in the absence of real anomalies. To this end, we develop robust mathematical models that emulate possible anomalies in time series data and propose a procedure for generating synthetic anomalies. Furthermore, we establish a theoretical framework for performance assessment based on a novel concept of distinguishability. In the second part, we employ these assessment tools to study the interaction between compression and anomaly detection from an information-theoretic standpoint. We demonstrate that common lossy compression algorithms can compromise the effectiveness of anomaly detection performed on compressed data. We then study how these tasks can be jointly optimized and offer insights for developing practical systems that integrate both functions. In a similar spirit, we design an autoencoder-based compression scheme that not only minimizes distortion but also preserves information critical for anomaly detection
Event reconstruction and analysis in the MUonE experiment
Get PDFThe MUonE experiment aims to measure the leading hadronic contribution to the muon anomaly , due to vacuum polarization, with precision better than 1\%. The proposed method is innovative, based on the measurement of the hadronic contribution to the running of the electromagnetic coupling in the space-like region of momentum transfer. The relevant process is the elastic scattering of 160\,\unit{\giga\electronvolt} muons off the atomic electrons of a low-Z target. The M2 beamline at CERN provides the necessary intensity to reach the statistical goal in few years of data taking. This thesis presents a study of the performance of reconstruction and new developments. One of the main objectives has been the optimization of the tracking algorithm to improve the reconstruction efficiency and the angular resolution, which are the most important figures in the detector design. With the optimal configuration, first results are presented from the 2023 Test Run data, and final considerations are made on the future developments for the experiment