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Enhancing federated learning through distributed ledger technology integration
No full textIn today's data-driven world, vast amounts of information power Machine Learning (ML) models for a wide range of applications. However, this data flow raises significant privacy concerns, as individuals are often reluctant to share personal information, especially given increasing regulations on data protection. Federated Learning (FL) offers a solution by training ML models directly on users' devices and sending only model updates to a central server. This distributed approach enables collaboration without sharing personal data, but challenges remain. Centralization may lead to server bottlenecks, reduced resilience, and fairness concerns if updates from certain devices are prioritized. Additionally, the lack of transparency and accountability can erode trust, while security risks, such as data poisoning and model inversion attacks, further complicate FL. Deployment can be costly and time-consuming, and participants may also lack incentives. Regulatory compliance, such as ensuring the right to be forgotten, adds complexity, as removing data from FL models without full retraining is challenging. This dissertation proposes integrating Distributed Ledger Technologies (DLTs) with FL to address these challenges. DLT decentralizes the aggregation process, enhancing security, transparency, and fairness through immutable record-keeping and traceability. Two DLT-based architectures are presented: one blockchain-based and the other using a Directed Acyclic Graph (DAG) for scalability. These approaches utilize Decentralized Identifiers (DIDs) and Verifiable Credentials (VCs) to track contributions and verify participants. Furthermore, a DLT-based FL as a Service (FLaaS) is introduced to simplify deployment, incorporating model validation to mitigate poisoning attacks and token-based incentives to encourage participation. Additionally, this dissertation outlines design guidelines for Federated Unlearning (FU), covering key evaluation metrics, existing techniques, and future research. Finally, a new unlearning algorithm is proposed to address adversarial settings and protect model integrity. These contributions pave the way for more secure, transparent, and resilient FL systems that can meet the needs of next-generation data-driven applications
New insights into the complex biology of osteoporosis: energy metabolism of bone cells, chemical and structural bone matrix properties and gut microbiota are involved in the etiopathogenesis
No full textOsteoporosis (OP) is a systemic skeletal disease with a complex and multifactorial etiology, associated with aging and characterized by a low bone mass and microarchitectural deterioration of bone tissue. OP poses a significant health burden and notable economic issues due to its high incidence among the population. OP fragility fractures result in disability and even premature death. Preventing bone fragility is of great importance for both patient health and the sustainability of healthcare systems, therefore in-depth understanding of the complex etiology of this disease is urgent. Molecular and chemical modifications of bone tissue, together with other systemic factors are involved in the etiopathogenesis of OP, thus underlining its complex pathogenesis.
Herein, three main aspects are explored: (i) the impact of monocarboxylate transporter MCT1 on osteocytes, focusing on the intracellular accumulation of lactate and protons that may play a role in osteocyte apoptosis and bone tissue health, (ii) chemical alterations in the inorganic and organic matrix of bone tissue may be related to bone fragility, and (iii) the imbalanced composition of gut microbiota as a possible cause of altered bone health. Molecular analyses of the energetic metabolism of osteocytes, spectroscopic analyses on bone tissue, and the characterization of the entire gut microbiota were performed on osteoporotic patients compared to healthy patients to underline potential characteristic signatures of OP. Results showed that: (i) MCT1 has a pivotal role in osteocytes survival and apoptosis; (ii) the inorganic matrix of bone tissue shows chemical alterations due to aging, being potential risk factors for bone tissue weakness, and (iii) gut microbiota composition exhibited dysbiosis in aged patients, an important task to be addressed with specific treatments. The collected data underline the importance of both prevention and treatment paying attention synergically to all the different risk factors, using a multidisciplinary approach
Interference mitigation techniques for cloud-RAN deployments in 5G and beyond systems
No full textThe deployment of ultra-dense networks is one of the most promising solutions to manage the phenomenon of co-channel interference that affects the latest wireless communication systems, especially in hotspots. To meet the requirements of the use-cases and the immense amount of traffic generated in these scenarios, 5G ultra-dense networks are being deployed using various technologies, such as distributed antenna system (DAS) and cloud-radio access network (C-RAN). Through these centralized densification schemes, virtualized baseband processing units coordinate the distributed access points and manage the available network resources. In particular, link adaptation techniques are shown to be fundamental to overall system operation and performance enhancement. The core of this dissertation is the result of an analysis and a comparison of dynamic and adaptive methods for modulation and coding scheme (MCS) selection applied to the latest mobile telecommunications standards. A novel algorithm based on the proportional-integral-derivative (PID) controller principles and block error rate (BLER) target has been proposed. Tests were conducted in a 4G and 5G system level laboratory and, by means of a channel emulator, the performance was evaluated for different channel models and target BLERs. Furthermore, due to the intrinsic sectorization of the end-users distribution in the investigated scenario, a preliminary analysis on the joint application of users grouping algorithms with multi-antenna and multi-user techniques has been performed. In conclusion, the importance and impact of other fundamental physical layer operations, such as channel estimation and power control, on the overall end-to-end system behavior and performance were highlighted
Design and testing of innovative, artificial intelligence-based techniques to model and control the combustion process and to reduce the Co2 emissions in modern, high-performance, gasoline direct injection engines
No full textThis work deals with the development of calibration procedures and control systems to improve the performance and efficiency of modern spark ignition turbocharged engines. The algorithms developed are used to optimize and manage the spark advance and the air-to-fuel ratio to control the knock and the exhaust gas temperature at the turbine inlet.
The described work falls within the activity that the research group started in the previous years with the industrial partner Ferrari S.p.a. .
The first chapter deals with the development of a control-oriented engine simulator based on a neural network approach, with which the main combustion indexes can be simulated.
The second chapter deals with the development of a procedure to calibrate offline the spark advance and the air-to-fuel ratio to run the engine under knock-limited conditions and with the maximum admissible exhaust gas temperature at the turbine inlet. This procedure is then converted into a model-based control system and validated with a Software in the Loop approach using the engine simulator developed in the first chapter. Finally, it is implemented in a rapid control prototyping hardware to manage the combustion in steady-state and transient operating conditions at the test bench.
The third chapter deals with the study of an innovative and cheap sensor for the in-cylinder pressure measurement, which is a piezoelectric washer that can be installed between the spark plug and the engine head. The signal generated by this kind of sensor is studied, developing a specific algorithm to adjust the value of the knock index in real-time. Finally, with the engine simulator developed in the first chapter, it is demonstrated that the innovative sensor can be coupled with the control system described in the second chapter and that the performance obtained could be the same reachable with the standard in-cylinder pressure sensors
Evaluation of the transcriptomic response of an Alzheimer's disease murine model induced at different ages: searching for predictors
No full textAlzheimer’s disease (AD) is a chronic, progressive neurodegenerative disease, characterized by the impairment of mnesic and cognitive functions, that represents the most frequent type of dementia in older people worldwide. Aging is the most important risk factor for the sporadic form of the pathology and it is associated to the progressive impairment of the proteostasis network. The endoplasmic reticulum (ER), the main cellular actor involved in proteostasis, appears significantly compromised in AD due to the accumulation of β-amyloid (Aβ) protein and phosphorylated-tau protein. Increasing proteins misfolding activates a specific cellular response known as Unfolded Protein response (UPR) which orchestrates the recovery of ER function.
The aim of the present study was to investigate the role of UPR and aging process in a murine model of AD induced by intracerebroventricular (i.c.v.) injection of Aβ1-42 oligomers at 3 or 18 months. The oligomers injection in aged animals caused the increased of memory impairment, oxidative stress, and the depletion of glutathione reserve. Furthermore, the RNA-sequencing analysis was performed and the bioinformatic analysis showed the enrichment of several pathways involved in neurodegeneration and protein regulations. The following analysis highlighted the significant dysregulation of the three branches of the UPR, the protein kinase RNA-like ER kinase (PERK), inositol-requiring protein 1α (IRE1α) and activating transcription factor 6 (ATF-6). In turn, ER stress affected the PI3K/Akt/Gsk3β and MAPK/ERK pathways, highlighting Mapkapk5 as a potential marker of the neurodegenerative process, which regulation could lead to the definition of new pharmacological and neuroprotective strategies to counteract AD
Characterization and management of particular classes of waste at a regional level. case study: Marche region
No full textThere are various methods to analyse waste, which differ from each other according to the level of detail of the compositio. Waste composed by plastic and used for packaging, for example, can be classified by chemical composition of the polymer used for the specific product. At a more basal level, before dividing a waste according to the specific chemical material of which it is composed it is possible and also important to classify it according to the material category. So, if the secondary aim is to consider the particular polymer that constitutes a plastic waste, or what kind of natural polymer composes a specific waste made of wood, the first aim is to classify the product category of the material that makes up the waste, so, if it is wood made, or plastic, or glass made or metal, or organic. There are not specific instruments to make this subdivision, not specific chemical tests, but only a manual recognition of the material that makes up the product or waste.
The first steps of this study is a recognition of the materials of which the waste is composed, the second is a the quantification of differentiated and unsorted waste produced in the area under study, the third is a mass balance of the portions of waste sent for recovery in order to obtain information on quantities that can be effectively recovered and ready for new life cycle as raw material; the fourth and last step is an environmental assessment that provides information on the environmental cost of the recovery process.
This process scheme is applied to various specific kinds of waste from separate collection generated in a specific area with the aim to find a model analysis appliable to other portions of territory in order to improve knowledge of recovery technologies
Transition Matters. The role of the designer in the sustainable and circular transition of polymeric materials
No full textLa ricerca indaga il ruolo del designer nella transizione sostenibile e circolare all’uso di materiali polimerici. Nel contesto contemporaneo la plastica è utilizzata in quasi ogni settore merceologico ma la sua futura applicazione è messa in forte discussione a causa dei visibili impatti ambientali del suo uso irresponsabile. Un passaggio netto dalla totale dipendenza alla liberazione dei polimeri è difficile; è necessario un periodo di transizione che permetta di coesistere responsabilmente con i polimeri in attesa di trovare dei validi sostituti. L’obiettivo della ricerca è lavorare su questo periodo ponendo il designer e le sue competenze come soggetti chiave del movimento. La tesi di ricerca propone un approccio per calare le pratiche del Transition Design nella progettazione di sistemi-prodotto, nutrendosi degli attributi anticipatori dell’Advanced Design e puntando agli obiettivi del Circular Design, lavorando a partire dalle merci più critiche nel contesto contemporaneo: quelle in polimero fossile non riciclabile. Contributo della tesi è la figura del Transition Matter Designer, un progettista di transizioni dei materiali che prevede metamorfosi di sistemi-prodotto nel tempo grazie alle sue competenze a diverse scale del progetto: forma l’utente agli atteggiamenti circolari e sostenibili, caratterizza i materiali per individuarne nuovi usi, seleziona i processi produttivi adatti a prevenire scarti e ne anticipa i cicli di vita nei prodotti. I Knitted Fasteners sono il risultato della simulazione del lavoro del Transition Matter Designer nel tessile: un sistema di elementi di fissaggio, personalizzabili dallo stilista e integrati negli abiti a maglia, che permettono di eliminare l’uso di fashion fasteners in plastica e metallo, elementi che rendono difficile il riciclo dei capi. Dalla sperimentazione è emerso il modello concettuale della Transindustrial Production: un lavoro di collaborazione fra Transition Matter Designer e creativo per dare identità ai materiali polimerici circolari attraverso l’ibridazione fra artigianato e industria, tipico del Made in Italy.The research investigates the role of the designer in the sustainable and circular transition to the use of polymeric materials. In the contemporary context, plastics are used in almost every product sector but their future application is strongly questioned due to the visible environmental impacts of their irresponsible use. A clean transition from total dependence to polymer liberation is difficult; a transition period is needed to responsibly co-exist with polymers while waiting to find viable substitutes. The aim of the research is to work on this period by placing the designer and his skills as key players. The research thesis proposes an approach to apply Transition Design practices into the design of product-systems, feeding on the anticipatory attributes of Advanced Design and aiming at the objectives of Circular Design, working from the most critical commodities in the contemporary context: those made of non-recyclable fossil polymer. The thesis proposes the figure of the Transition Matter Designer, a designer of material transitions who envisages metamorphoses of product-systems over time thanks to his skills at different scales of design: he trains users in circular and sustainable attitudes, characterises materials to identify new uses, selects suitable production processes to prevent waste and anticipates materials life cycles in products. The Knitted Fasteners are the result of the simulation of the Transition Matter Designer's work in textiles: a system of fasteners, customisable by the designer and integrated into knitted garments, which make it possible to eliminate the use of plastic and metal fashion fasteners, elements that make it difficult to recycle garments. From the experimentation emerged the conceptual model of Transindustrial Production: a collaborative work between Transition Matter Designer and stylist to give identity to circular polymeric materials through the hybridisation of craftsmanship and industry, typical of Made in Italy
Positive Energy Districts model. Innovative approaches and operative tools for the transition towards climate-neutral cities
No full textAd oggi le città europee si configurano come i principali centri di cultura, innovazione e sviluppo economico. Tuttavia, ospitando circa il 75% della popolazione e consumando quasi l’80% dell’energia prodotta, a causa delle significative emissioni di gas serra esse contribuiscono in modo rilevante ai cambiamenti climatici e, allo stesso tempo, ne subiscono gli effetti più intensi.
La Comunità Europea ha preso atto della necessità di intraprendere un’azione sinergica che adotti strategie di mitigazione climatica e preveda misure di adattamento per far fronte agli impatti climatici ormai inevitabili. L'orientamento dei Programmi europei di Ricerca e Innovazione sul tema delle città smart e clima-neutrali sposta l'attenzione dalla dimensione urbana verso la scala di distretto. In questa prospettiva, i Positive Energy Districts (PEDs) si configurano come distretti di nuova edificazione, ma anche come soluzioni ambiziose per la riqualificazione di quartieri esistenti che gestiscono in modo attivo il fabbisogno energetico con un bilancio nullo di emissioni e un surplus di energia prodotta da rinnovabili.
La ricerca di dottorato focalizza l’indagine sul modello PEDs esplorandone il potenziale di applicabilità nel contesto urbano consolidato. Nello specifico, la tesi lavora allo sviluppo di due contributi di ricerca originali: il PED-Portfolio e il PED-Toolkit. Tali contributi propongono un approccio sistemico, attraverso il quale intraprendere un percorso di conoscenza e sperimentazione del modello PEDs in una prospettiva di riduzione del fabbisogno energetico, ma anche in un’ottica di migliore accessibilità, vivibilità e resilienza di questi distretti.
Al fine di verificare l’applicabilità dei risultati della ricerca, gli strumenti sviluppati vengono testati su un’area pilota e gli esiti di tale sperimentazione sono poi messi a confronto con il quadro dello stato dell’arte e con le principali linee di ricerca internazionali sul tema PEDs, affinando gli esiti del progetto di dottorato in un processo di ricerca-sperimentazione-ricerca.Nowadays European cities are considered the main centers of culture, innovation, and economic growth. However, hosting around 75% of the population and consuming almost 80% of the energy produced, due to the high greenhouse gas emissions they also significantly contribute to climate change, and, at the same time, they suffer the most intense effects of this phenomenon.
The European Community has taken note of the need to undertake a synergic action that, on the one hand, includes climate mitigation strategies, containing emissions, and, on the other hand, introduces adaptation measures to cope with inevitable climate impacts and their economic, social, and environmental costs. The orientation of European Research and Innovation (R&I) programs concerning smart and climate-neutral cities shifts the focus from the urban dimension towards the district scale. In this perspective, Positive Energy Districts (PEDs) are new construction settlements, but also ambitious solutions for neighbourhood renovation that actively manage the energy demand with a zero annual CO2 emissions balance and with an energy surplus produced from renewable sources.
The Ph.D. research focuses the investigation on the PEDs model by exploring its applicability potential in the urban consolidated environment. Specifically, the thesis works on the development of two original research contributions: the PED-Portfolio and the PED-Toolkit. These contributions propose a systemic approach through which it is possible to undertake a path of understanding and experimentation (of the PEDs model in a view of an energy demand reduction, but also in the perspective of an improved districts’ accessibility, liveability, and resilience.
To verify the concrete applicability of research results, the developed tools are tested on a pilot area and the outcomes are compared with the state-of-the-art framework and with the main international lines of research on the PEDs topic, implementing and refining Ph.D. project results in a circular process of research-experimentation-research
Developing a methodology for co-creation using extended reality technologies.
No full textAmid the remarkable growth of innovative technologies, particularly immersive technologies like Extended Reality (XR) (comprising of Virtual Reality (VR), Augmented Reality (AR) & Mixed Reality (MR)), a transformation is unfolding in the way we collaborate and interact. The current research takes the initiative to explore XR’s potential for co-creation activities and proposes XR as a future co-creation platform. It strives to develop a XR-based co-creation system, actively engage stakeholders in the co-creation process, with the goal of enhancing their creative businesses. The research leverages XR tools to investigate how they can enhance digital co-creation methods and determine if the system facilitates efficient and effective value creation during XR-based co-creation sessions.
In specific terms, the research probes into whether the XR-based co-creation method and environment enhances the quality and novelty of ideas, reduce communication challenges by providing better understanding of the product, problem or process and optimize the process in terms of reduction in time and costs. The research introduces a multi-user, multi-sensory collaborative and interactive XR platform that adapts to various use-case scenarios. This thesis also presents the user testing performed to collect both qualitative and quantitative data, which serves to substantiate the hypothesis. What sets this XR system apart is its incorporation of fully functional prototypes into a mixed reality environment, providing users with a unique dimension within an immersive digital landscape.
The outcomes derived from the experimental studies demonstrate that XR-based co-creation surpasses conventional desktop co-creation methods and remarkably, the results are even comparable to a full mock-up test. In conclusion, the research underscores that the utilization of XR as a tool for co-creation generates substantial value. It serves as a method that enhances the process, an environment that fosters interaction and collaboration, and a platform that equips stakeholders with the means to engage effectively
Decoding Agc1 deficiency: bioinformatics approaches to unveil the functional implications of Slc25a12 on the transcriptome and epigenome
No full textIn the brain, mutations in SLC25A12 gene encoding AGC1 cause an ultra-rare genetic disease reported as a developmental and epileptic encephalopathy associated with global cerebral hypomyelination. Symptoms of the disease include diffused hypomyelination, arrested psychomotor development, severe hypotonia, seizures and are common to other neurological and developmental disorders. Amongst the biological components believed to be most affected by AGC1 deficiency are oligodendrocytes, glial cells responsible for myelination. Recent studies (Poeta et al, 2022) have also shown how altered levels of transcription factors and epigenetic modifications greatly affect proliferation and differentiation in oligodendrocyte precursor cells (OPCs).
In this study we explore the transcriptomic landscape of Agc1 in two different system models: OPCs silenced for Agc1 and iPSCs from human patients differentiated to neural progenitors. Analyses range from differential expression analysis, alternative splicing, master regulator analysis. ATAC-seq results on OPCs were integrated with results from RNA-Seq to assess the activity of a TF based on the accessibility data from its putative targets, which allows to integrate RNA-Seq data to infer their role as either activators or repressors.
All the findings for this model were also integrated with early data from iPSCs RNA-seq results, looking for possible commonalities between the two different system models, among which we find a downregulation in genes encoding for SREBP, a transcription factor regulating fatty acids biosynthesis, a key process for myelination which could explain the hypomyelinated state of patients. We also find that in both systems cells tend to form more neurites, likely losing their ability to differentiate, considering their progenitor state. We also report several alterations in the chromatin state of cells lacking Agc1, which confirms the hypothesis for which Agc1 is not a disease restricted only to metabolic alterations in the cells, but there is a profound shift of the regulatory state of these cells