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Evaluation of alterations of milk microbiota during medical treatment in the lactation period: application of a Göttingen Minipigs sows animal model
No full textEarly gut microbiota (GM) dysbiosis can affect infant’s health and it has been associated to the onset of several pathologies. Breastfeeding is one of the major factors influencing the structure and composition of the infant’s GM. Breast milk provides the infant not only nutrients, bacteriostatic compounds and prebiotic molecules, but it also harbours its own microbiota. The milk microbiota is a dynamic entity shaped by several factors, including maternal medical treatments. A dysbiosis of the milk microbiota could affect the infant’s GM composition. However, the impact of pharmacological treatments on the milk microbiota remains largely unknown. The IMI ConcePTION project aims to produce and disseminate knowledge on the effects of drugs taken during breastfeeding. This thesis contributed to this goal by developing a methodology to investigate the impact on the milk microbiota of amoxicillin, an antibiotic, and metformin, a common treatment for type 2 diabetes. The Göttingen Minipigs® was chosen as animal model because of its physiological and metabolic similarities to humans. Göttingen Minipigs® sows were administered daily either amoxicillin or metformin for three weeks starting from the second week of lactation. Bacterial populations in sows’ milk, sows’ feces and piglets’ rectal swabs were analyzed through sequencing of the V3-V4 hypervariable regions of the 16S rRNA bacterial gene. The Göttingen Minipigs® was revealed to be a suitable translational model for microbiota studies. Sows' milk microbiota composition showed similarities with humans, and we were able to identify changes of taxa relative abundance in both gut and milk. Drug-related changes in milk microbiota did not seem to have detrimental effects. Overall, these results suggest that continuing breastfeeding during maternal treatment with the analyzed drugs should not have any milk microbiota-mediated effect on the infant health. However, further studies are needed to determine the effect of maternal treatment on the piglets’ GM
Development of a novel computational framework to gain mechanistic insights of atrial fibrillation and optimize therapeutic strategies
No full textAtrial fibrillation (AF) is associated with a fivefold increase in stroke risk and accounts for 15–18% of all strokes. Stroke prevention relies on the CHA₂DS₂-VASc score, which, based on general clinical factors, lacks patient-specific predictive accuracy. To overcome this limitation, computational fluid dynamics (CFD) simulations have emerged as a valuable tool, enabling detailed analysis of left atrial appendage (LAA) blood flow and identifying stasis-prone regions with high thrombotic risk.
This research focuses on developing a digital twin model of the left atrium (LA), integrated with an advanced CFD framework to quantify patient-specific hemodynamic parameters in different AF types, including paroxysmal and persistent AF. Special attention is given to LAA flow dynamics, crucial for stroke risk assessment. The model incorporates contrast-enhanced CT and Doppler imaging to personalize LA simulations, enhancing clinical decision-making and guiding therapeutic strategies.
Beyond CFD-based stroke risk assessment, this thesis explores AF-related mechanisms and interventions, particularly the role of pulmonary vein (PV) contractions in AF progression and left atrial appendage occlusion (LAAO) as an alternative stroke prevention strategy. Additionally, it investigates the use of 3D-printed models to simulate LAAO device placement, improving procedural outcomes.
Findings highlight the potential of computational modeling in refining risk stratification, thromboembolic predictions, and treatment optimization. This comprehensive approach underscores the role of digital twin and CFD models in transforming AF management, offering personalized stroke prevention strategies, improved device testing, and patient-centered care
Analysis of lexical errors in the written production of Chinese-speaking learners of L3 Italian
No full textCon lo sviluppo dell'economia mondiale e l'integrazione politica, il multilinguismo e l'acquisizione di più lingue assumono un'importanza crescente. In Cina, sempre più persone studiano lingue straniere, tra cui l'italiano. Questa ricerca, basata sul concetto di "terza lingua" e sulla linguistica dei corpora, analizza gli errori lessicali nella produzione scritta di apprendenti cinesi di italiano. Gli obiettivi principali sono: 1) esaminare l'influenza del cinese (lingua madre) e dell'inglese (prima lingua straniera) sugli errori lessicali in italiano; 2) identificare le cause di tali errori; 3) suggerire metodi per migliorare l'acquisizione del lessico italiano.
L'approccio è interdisciplinare, integrando l'acquisizione della terza lingua, la linguistica dei corpora e l'analisi degli errori. È stato analizzato un corpus di testi scritti da studenti cinesi di sette istituzioni accademiche, seguendo la classificazione degli errori lessicali proposta da James (2013): errori di selezione delle forme (ES), errori di formazione (EF), errori di distorsione (ED), errori di confusione delle relazioni di senso (ER) ed errori di collocazione (EC). L'analisi è stata condotta con strumenti digitali per l’annotazione, la classificazione, l’analisi e la verifica degli errori.
I risultati principali mostrano che: 1) gli errori più frequenti riguardano la confusione delle relazioni di senso, mentre quelli di distorsione e formazione sono i meno comuni; 2) il cinese influenza maggiormente gli errori lessicali, seguito dalla confusione tra parole simili in italiano, con minore influenza dell'inglese; 3) la quantità di errori diminuisce con l'aumentare della competenza linguistica, con differenze significative negli errori di formazione tra principianti e avanzati.
I risultati rivelano le difficoltà degli apprendenti cinesi nell'acquisizione del lessico italiano, proponendo metodologie didattiche in linea con l'insegnamento dell'italiano in Cina, offrendo nuove prospettive per migliorare l'efficacia nell'apprendimento del lessico.With the development of the global economy and political integration, multilingualism and the acquisition of multiple languages are becoming increasingly important. In China, more and more people are studying foreign languages, including Italian. This research, based on the concept of "third language acquisition" and corpus linguistics, analyzes lexical errors in the written production of Chinese learners of Italian. The main objectives are: 1) to examine the influence of Chinese (native language) and English (first foreign language) on lexical errors in Italian; 2) to identify the causes of these errors; 3) to suggest methods to improve Italian vocabulary acquisition.
The approach is interdisciplinary, integrating third language acquisition, corpus linguistics, and error analysis. A corpus of texts written by Chinese students from seven academic institutions was analyzed, following the classification of lexical errors proposed by James (2013): selection errors (ES), formation errors (EF), distortion errors (ED), confusion of sense relations errors (ER), and collocation errors (EC). The analysis was conducted using digital tools for annotation, classification, analysis, and verification of errors.
The main results show that: 1) the most frequent errors involve the confusion of sense relations, while distortion and formation errors are the least common; 2) Chinese has the greatest influence on lexical errors, followed by confusion between similar Italian words, with English having a lesser influence; 3) the number of errors decreases as language competence increases, with significant differences in formation errors between beginners and advanced learners.
The findings reveal the difficulties Chinese learners face in acquiring Italian vocabulary, proposing teaching methodologies aligned with Italian language education in China and offering new perspectives to improve vocabulary learning effectiveness
Synthesis, structural investigation and biological applications of novel Carbonyl Ruthenium (II) complexes
No full textThis work presents the synthesis with moderate to good yields, structural elucidation, and biological studies of novel Ru(II) complexes with potential anticancer and antimicrobial applications. The description emphasizes the reactivity of [Ru(H)₂(CO)(PPh₃)₃] with a plethora of organic ligands, exploring their dynamic coordination behavior, physical-chemical properties, and biological activity. Overall, this work highlights the versatility of Ru(II) complexes in coordinating diverse kinds of ligands, yielding species with tunable properties for medicinal applications. The utilized methods sustain the potential of these complexes as anticancer and antimicrobial agents, provide insight into their biological targets and mechanisms of action, pointing the way to future therapeutic developments with minor drawbacks
Multi-organ support device for combined extracorporeal carbon dioxide removal and hemofiltration treatments with pump-free solution for ultrafiltration
No full textThe use of extracorporeal organ support (ECOS) devices is increasingly widespread, to temporarily sustain or replace the functions of impaired organs in critically ill patients. Among ECOS, respiratory functions are supplied by extracorporeal life support (ECLS) therapies like extracorporeal membrane oxygenation (ECMO) and extracorporeal carbon dioxide removal (ECCO2R), and renal replacement therapies (RRT) are used to support kidney functions. However, the leading cause of mortality in critically ill patients is multi-organ dysfunction syndrome (MODS), which requires a complex therapeutic strategy where extracorporeal treatments are often integrated to pharmacological approach. Recently, the concept of multi-organ support therapy (MOST) has been introduced, and several forms of isolated ECOS devices are sequentially connected to provide simultaneous support to different organ systems. The future of critical illness goes towards the development of extracorporeal devices offering multiple organ support therapies on demand by a single hardware platform, where treatment lines can be used alternately or in conjunction. The aim of this industrial PhD project is to design and validate a device for multi-organ support, developing an auxiliary line for renal replacement therapy (hemofiltration) to be integrated on a platform for ECCO2R. The intended purpose of the ancillary line, which can be connected on demand, is to remove excess fluids by ultrafiltration and achieve volume control by the infusion of a replacement solution, as patients undergoing respiratory support are particularly prone to develop fluid overload. Furthermore, an ultrafiltration regulation system shall be developed using a powered and software-modulated pinch-valve on the effluent line of the hemofilter, proposed as an alternative to the state-of-the-art solution with peristaltic pump
The ritual performance of the Nava Durgā: music and dance among the Banmālās in Bhaktapur, Nepal
No full textIl presente lavoro è il risultato di cinque anni di ricerca sulla performance rituale delle Nava Durgā del popolo newar a Bhaktapur (Nepal). Dal 1512, per circa nove mesi all'anno, gli uomini della casta inferiore Banmālā reincarnano le nove manifestazioni femminili della dea Durgā ed eseguono le danze in maschera. La performance della Nava Durgā è una pratica culturale molto complessa, composta da suoni, danze, processioni, momenti di venerazione (pūjā), rituali tantrici e momenti sacrificali.
Gli aspetti musicali e teatrali della performance costituiscono il focus dell’indagine di questo studio. Dopo una descrizione analitica degli strumenti musicali utilizzati nella performance, alcuni elementi sonori vengono trascritti e analizzati mettendo in luce le caratteristiche tipiche della musica newar.
I contenuti narrativi delle danze e il ciclo vitale delle Nava Durgā rispecchiano la vita hindu. La loro interpretazione viene realizzata in base alle osservazioni etnografiche; alcuni temi che costituiscono gli obiettivi dei devoti hindu (puruṣārtha) vengono esaminati attraverso l’approccio storico e quello etnografico, anche al fine di sottolineare il ruolo didascalico e formativo della performance.
Un altro argomento discusso in questo lavoro consiste nell'identità dei danzatori Banmālā e quella del popolo newar in generale; questo aspetto è emerso in modo rilevante anche durante le fasi di mediatizzazione della performance delle Nava Durgā avvenute nel periodo del COVID-19. Da questo punto di vista, il presente lavoro costituisce un contributo alla diffusione della conoscenza della tradizione delle Nava Durgā; questo converge con l'obiettivo dei Banmālā di aumentare la visibilità della performance al fine di affermare la propria identità sia nel contesto nazionale che in quello internazionale.This dissertation presents the results of five years of research on the Hindu ritual performance by the Nava Durgā of the Newar people in Bhaktapur, Nepal. Since 1512, groups of men from the lower Banmālā caste have been reincarnating the nine female manifestations of the goddess Durgā, performing mask dances for almost nine months per year. The performance of the Nava Durgā is a highly complex musical tradition composed of sounds, dances, processions, venerations (pūjā) and tantric rituals such as sacrifices.
The musical and theatrical aspects of the performance form the principal focus of this study. The musical instruments used in the rituals are described, and some of the sonic elements have been transcribed and their sound spectra analysed, bringing to light some typical characteristics of Newar music. The narrative contents of the dances and the life cycle of the Nava Durgā both mirror Hindu life. This interpretation of the performance is based on ethnographic observations; certain themes which constitute the objects of human pursuit (puruṣārtha) of the Hindu tradition are examined using both historical and ethnographic approaches to underline the instructive role of the performance.
A further consideration is the identity issue facing the Banmālā community and the Newar people in general. This became clearer to the outside world following the mediatization of the performances which occurred during the Covid-19 pandemic. Presenting results of this study is also a way to disseminate the tradition of the Nava Durgā; this converges with the objective of the community to increase the visibility of their performances, in order to affirm their identity in a national and international context. From this perspective, this dissertation also represents a contribution to the community’s effort
Volumetric growth of uterine myomas: analysis of risk factors
No full textI miomi uterini sono la neoplasia uterina più comune e colpiscono fino al 30% delle donne in età fertile. Nonostante l’elevata prevalenza, pochi studi in Letteratura hanno analizzato i fattori di rischio per la crescita dei miomi uterini, mostrando spesso dei risultati contrastanti. Nel nostro studio osservazionale prospettico sono state arruolate pazienti che rispettassero i criteri di inclusione e di esclusione, con diagnosi di miomi uterini evidenziati mediante ecografia eseguita presso i nostri ambulatori, a partire da giugno 2017. A partire da gennaio 2019, sono state ricercate mensilmente le pazienti precedentemente arruolate che erano tornate presso i nostri ambulatori per esecuzione di ulteriore ecografia, a distanza di 24 ± 5 mesi, fino a raggiungere il campione designato, cioè 450 pazienti totali. È stato, quindi, valutato il tasso di crescita annuo del mioma di maggiori dimensioni ed è stato utilizzato l'approccio polinomiale frazionario multivariabile per selezionare i fattori di rischio anamnestici ed ecografici legati all’incremento volumetrico. Circa la metà dei miomi uterini analizzati ha mostrato stabilità dimensionale nel corso del follow-up (crescita ≤10%), mentre la restante metà ha mostrato una crescita > 10%. Il solo fattore di rischio associato alla crescita volumetrica dei miomi uterini è risultato essere il volume del mioma durante l’ecografia di arruolamento (P = 0.001), quindi miomi di piccole dimensioni presentano un tasso di crescita maggiore rispetto ai miomi di grandi dimensioni. Lo studio ha raccolto la più ampia casistica in Letteratura nella valutazione del naturale andamento di modifica dimensionale dei miomi uterini. Sebbene siano necessari ulteriori studi con campione più ampio, questi dati possono fornire un utile supporto per eseguire un adeguato counselling con le pazienti nella pratica clinica quotidiana.Uterine myomas are the most common uterine neoplasm, affecting up to 30% of women of childbearing age. Despite the high prevalence, in Literature few studies have analysed the risk factors for the growth of uterine myomas, showing often conflicting results. In our prospective observational study, we enrolled patients who met the inclusion and exclusion criteria, with uterine myomas diagnosed by ultrasound performed in our outpatient clinic, starting from June 2017. From January 2019, we evaluated all the previously enrolled patients who had returned to our clinics for further ultrasound, until reaching the designated sample of 450 patients. Therefore, the annual growth rate of the largest myoma was evaluated and the multivariable fractional polynomial approach was used to select anamnestic and/or ultrasonographic risk factors associated to the volumetric growth. About half of the uterine myomas analysed showed dimensional stability during the follow-up (growth ≤10%), while the remaining half showed growth > 10%. The only risk factor associated with the volumetric growth of uterine myomas was the volume of the myoma during the first ultrasound (P = 0.001): small myomas have a higher growth rate than large myomas. Our study collected the largest case series in Literature for the evaluation of the natural course of dimensional modification of uterine myomas. Although further studies with larger sample sizes are needed, these data could provide useful support for adequate patient counselling during daily clinical practice
Innovation in conceptual design of chemical processes
No full textNowadays, the chemical industry has reached significant goals to produce essential components for human being. The growing competitiveness of the market caused an important acceleration in R&D activities, introducing new opportunities and procedures for the definition of process improvement and optimization. In this dynamicity, sustainability is becoming one of the key aspects for the technological progress encompassing economic, environmental protection and safety aspects.
With respect to the conceptual definition of sustainability, literature reports an extensive discussion of the strategies, as well as sets of specific principles and guidelines. However, literature procedures are not completely suitable and applicable to process design activities. Therefore, the development and introduction of sustainability-oriented methodologies is a necessary step to enhance process and plant design. The definition of key drivers as support system is a focal point for early process design decisions or implementation of process modifications. In this context, three different methodologies are developed to support design activities providing criteria and guidelines in a sustainable perspective. In this framework, a set of key Performance Indicators is selected and adopted to characterize the environmental, safety, economic and energetic aspects of a reference process. The methodologies are based on heat and material balances and the level of detailed for input data are compatible with available information of the specific application.
Multiple case-studies are defined to prove the effectiveness of the methodologies. The principal application is the polyolefin productive lifecycle chain with particular focus on polymerization technologies. In this context, different design phases are investigated spanning from early process feasibility study to operative and improvements assessment. This flexibility allows to apply the methodologies at any level of design, providing supporting guidelines for design activities, compare alternative solutions, monitor operating process and identify potential for improvements
Analysis and improvements of four-wire power converters for electric vehicle chargers
No full textA robust and well-distributed backbone charging network is the priority to ensure widespread electrification of road transport, providing a driving experience similar to that of internal combustion engine vehicles. International standards set multiple technical targets for on-board and off-board electric vehicle chargers; output voltage levels, harmonic emissions, and isolation requirements strongly influence the design of power converters. Additionally, smart-grid services such as vehicle-to-grid and vehicle-to-vehicle require the implementation of bi-directional stages that inevitably increase system complexity and component count. To face these design challenges, the present thesis provides a rigorous analysis of four-leg and split-capacitor three-phase four-wire active front-end topologies focusing on the harmonic description under different modulation techniques and conditions. The resulting analytical formulation paves the way for converter performance improvements while maintaining regulatory constraints and technical requirements under control. Specifically, split-capacitor inverter current ripple was characterized as providing closed-form formulations valid for every sub-case ranging from synchronous to interleaved PWM. Outcomes are the base for a novel variable switching PWM technique capable of mediating harmonic content limitation and switching loss reduction. A similar analysis is proposed for four-leg inverters with a broad range of continuous and discontinuous PWM modulations. The general superiority of discontinuous PWM modulation in reducing switching losses and limiting harmonic emission was demonstrated. Developments are realized through a parametric description of the neutral wire inductor. Finally, a novel class of integrated isolated converter topologies is proposed aiming at the neutral wire delivery without employing extra switching components rather than the one already available in typical three-phase inverter and dual-active-bridge back-to-back configurations. The fourth leg was integrated inside the dual-active-bridge input bridge providing relevant component count savings. A novel modified single-phase-shift modulation technique was developed to ensure a seamless transition between working conditions like voltage level and power factor. Several simulations and experiments validate the outcomes
Electrospinning of polymeric composites with GRMs for different industrial applications
No full textElectrospinning is the most common and industrially scalable technique for the production of polymeric nanofibers.
Currently, nanocomposites are drawing much interest for their excellent properties in terms of flexibility, electrical conductivity and high surface area, which enhances the interaction with the surrounding environment.
The objective of this thesis was the optimization of different electrospinning setups for the production of nanostructured polymeric composites using graphene-related materials as nanofillers. Such composites were obtained using different polymers as matrix (polyamide 6, polyinylidene fluoride and polylactic acid) that were selected and combined with the appropriate reinforcements based on their properties and their interest for specific applications.
Moreover, this study highlighted the possibility to tune the morphology and size of the produced nanofibers by the addition of appropriate nanofillers even in low amounts. The addition of only 0.5% of GO allowed the production of smooth nanofibers with diameters up to 75% thinner (in the case of PLA) than the ones obtained from the pristine polymer.
PVdF was charged with GO to produce triboelectric materials that can be exploited in a wearable nanogenerator for the conversion of human motion energy in electrical energy. The addition of GO improved the open-circuit voltage and power-output of a generator prototype by 3.5 times.
Electrospun PA6 membranes were coated with rGO using a simple two-step technique to produce conductive textiles for wearable electronic applications. The sheet resistance of the produced materials was measured in approximately 500 Ω/sq and their resistance to washing and bending was successfully tested. These materials could be exploited as strain sensors or heating elements in smart textiles.
PLA was co-electrospun with GO and cellulose nanofibers to produce high-surface area and porosity mats that could be exploited for the production of functionalized highly selective adsorption membranes with low pressure drops