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Response of the Benguela upwelling system to four decades of global warming
No full textThe Benguela upwelling system (BUS) stands out as one of the most productive marine systems in the world's oceans, providing significant ecological and economic value. This productivity primarily arises from the upwelling process, where equator-ward alongshore winds, coupled with Earth's rotation, drive the offshore movement of shallow coastal waters, causing the ascent of deep, cold, nutrient-rich waters, thereby fuelling primary production. Given the importance of the BUS, understanding the potential impacts of ongoing climate warming is crucial. Climate warming may alter atmospheric pressure gradients, potentially intensifying upwelling-favourable winds, a concept known as the "Bakun hypothesis". However, this hypothesis remains debated within the scientific community. The objectives of this dissertation were to determine whether there has been an intensification of the winds driving the BUS and, if so, to identify the principal physical and biogeochemical changes resulting from this intensification. Physical alterations examined include Ekman offshore transport, while biogeochemical changes encompass three major aspects: Chlorophyll-a concentrations as a proxy for algal blooming, food web structures, and dissolved oxygen dynamics within the system, focusing on hypoxic water masses. Previous studies addressing similar questions have faced limitations due to the system's complexity and the scarcity of observational data covering long periods to address long-term trends. To overcome these challenges, this dissertation investigates the BUS over four decades from 1980 to 2020, using a highly resolved coupled physical-biogeochemical model via the NEMO-BFM modeling suites, employing a nesting approach with a horizontal resolution of 1/16° over the BUS domain, nested from a global ocean domain with a resolution of 1/4°
New chemical modalities for leishmaniasis drug discovery
No full textLeishmaniasis is one of the major parasitic diseases among neglected tropical diseases with a high rate of morbidity and mortality. Human migration and climate change have spread the disease from limited endemic areas all over the world, also reaching regions in Southern Europe, and causing significant health and economic burden. The currently available treatments are far from ideal due to host toxicity, elevated cost, and increasing rates of drug resistance. Safer and more effective drugs are thus urgently required. Nevertheless, the identification of new chemical entities for leishmaniasis has proven to be incredibly hard and exacerbated by the scarcity of well-validated targets. Trypanothione reductase (TR) represents one robustly validated target in Leishmania that fulfils most of the requirements for a good drug target. However, due to the large and featureless active site, TR is considered extremely challenging and almost undruggable by small molecules. This scenario advocates the development of new chemical entities by unlocking new modalities for leishmaniasis drug discovery. The classical toolbox for drug discovery has enormously expanded in the last decade, and medicinal chemists can now strategize across a variety of new chemical modalities and a vast chemical space, to efficiently modulate challenging targets and provide effective treatments. Beyond others, Targeted p
Protein Degradation (TPD) is an emerging strategy that uses small molecules to hijack endogenous proteolysis systems to degrade disease-relevant proteins and thus reduce their abundance in the cell. Based on these considerations, this thesis aimed to develop new strategies for leishmaniasis drug discovery while embracing novel chemical modalities and navigating the chemical space by chasing unprecedented chemotypes. This has been achieved by four complementary projects. We believe that these next-generation chemical modalities for leishmaniasis will play an important role in what was previously thought to be a drug discovery landscape dominated by small molecules
Historic and modern alloys: atmospheric corrosion and development of accelerated ageing methodologies
No full textThe atmospheric corrosion of modern and historic alloys used in cultural heritage has been investigated by applying specific accelerated ageing methods. Three main research lines were carried out, involving different materials. In the first part, the atmospheric corrosion of a modern Cu-3Si-1Mn bronze was investigated through accelerated ageing tests simulating outdoor runoff conditions. The corrosion processes were evaluated through different analyses, and the results obtained were compared to those of a traditional quaternary bronze. The second line was carried out to characterise historic aluminium alloys used in aeronautics to develop and apply innovative protection strategies for their conservation. Historic wrecks were identified and characterised through micro and macroscale observations. Moreover, accelerated ageing tests were performed on both historic and modern alloys to compare their behaviour and select the best modern substrate to be used for the development of effective coatings. The third research line aimed to develop accelerate sampling and ageing methods to investigate the role of particulate matter (PM) in the atmospheric corrosion of bronzes and metals in general. The first approach consisted in the fine-tuning of an efficient accelerated method for ambient PM sampling on bronze specimens followed by their accelerated ageing, in order to establish a correlation between the PM and the substrate’s corrosion. After the accelerated ageing of the specimens, the corrosion was evaluated by surface characterisation and correlated to the PM features. The second approach consisted in the development of a synthetic PM formulation and of an artificial deposition method, which was performed by spraying mixtures containing the main PM inorganic fractions on a G-85 bronze with an airbrush. The deposition efficiency was assessed, and the effect of synthetic PM on the bronze corrosion was evaluated. The results were compared to those obtained by ambient PM deposition
Sealing practices in the Near East during the Late Bronze II period: administration and trade in the age of internationalism
No full textThis PhD research investigates sealing practices in the Near East during the Late Bronze II period (ca. 1375-1175 BCE). Sealings from archaeological contexts in the Southern Levant, North Syria, Upper and Lower Mesopotamia and South-Western Iran are taken under consideration and analyzed on multiple aspects at local, regional, and international levels. The contextual, functional, and iconographic analysis of these materials, in fact, allows to reconstruct the nature of the transactions and the agents involved in the sealing operations within local administrative systems, highlighting at the same time aspects of inter-regional interactions during the age of internationalism. Following a survey of the available evidence, a corpus consisting of 1845 records from 28 different sites across the ANE, has been filed using MS Access and MS Excel, including 740 unpublished sealing from Karkemish. Among this large evidence, the corpus of recently discovered sealings from Karkemish and the other scattered sealings from the North Syrian provinces, for instance, provide insights on the core-periphery relationships under the Hittite Empire; while the deposit from Building P at Tell Sheikh Hamad, that of the Middle Assyrian houses at Tell Fekheriye, and of the dunnu of Tell Sabi Abyad, significantly contributes to defining the administration of provinces within the Middle Assyrian state and the regional circulation of good. The less extensive evidence from South Mesopotamia under the Kassite rule and from Middle Elamite contexts in South-Western Iran somewhat contribute as well to the understanding of sealing practices in the LB II period. The South Levantine kingdoms, on the other hand, seems participates to the Egyptian regional network of exchanges and sealing practices
Innovative and sustainable strategies in asymmetric synthesis and waste recycling: towards a circular economy model
No full textThe research activity carried out during my PhD aimed to develop novel processes embracing a greener and more sustainable perspective, by following the 12 Principles of Green Chemistry. This work explored Switchable Solvents (SS), Polydiacetylenes (PDA), and stereoselective cycloadditions, and among these diverse areas of research, a common theme and guideline has been a focus on sustainability and the pursuit of simplification. For Switchable Solvents, I investigated their use as alternative, smart media for organocatalytic reactions, enabling catalyst recycling and reuse. Various asymmetric reactions catalyzed by aminocatalysts were tested, yielding promising results in terms of both efficiency and stereoselectivity. While the solvent was successfully recycled, catalyst recovery was partial but holds potential for improvement. SS were also applied to multilayered packaging waste, enabling the delamination and separation of aluminum and polymeric layers that were efficiently recovered with preserved properties. Regarding PDA, I explored the use of these innovative materials to develop recyclable heterogeneous organocatalysts. Their self-assembly and polymerization properties were exploited to create a robust and manageable supported organocatalyst which was tested in aldol reactions with good results and recyclability. Finally, during my visiting period in professor Jørgensen’s group, I cooperated in the development of two projects. The first concerned the synthesis of heterotropones derivatives, easily obtained through a nucleophilic aromatic substitution on triflated tropolone employing different nucleophiles. The reactivity of these new compounds in [4+2] cycloaddition reactions with dienophiles was also studied and efficiently demonstrated. The second project was targeted to the development of Brønsted-base catalysed (3+2) annulations between donor-acceptor cyclopropanes and nitrosoarenes, accessing chiral substituted isoxazolidines. High conversion and enantiomeric excesses were achieved, allowing for the extension to different substrates, with a broad scope and excellent results
Smart cities and transport: evaluating and leveraging big data to address and promote sustainable and accessible urban mobility
No full textThe advent of Big Data has profoundly altered the landscape of data science, particularly in the context of smart cities. As organisations increasingly rely on data-driven insights, the challenges associated with Big Data, such as data privacy, ethical implications and the need for sophisticated analytical tools, become more pronounced. This doctoral thesis examines the complex and far-reaching effects of Big Data on the transportation sector, a pivotal element of urban infrastructure. The objective of this research is to conduct a comprehensive evaluation of the current state of Big Data, with a particular emphasis on the necessity for innovative data management and analysis approaches. The thesis is structured in such a way as to first present a comprehensive discussion of the concepts of smart cities and big data, with particular emphasis on the interdependencies between the two and the inherent drawbacks of each.
The following chapters examine the applications of Big Data in transportation, demonstrating how integrated data sources can address existing research gaps and enhance urban mobility. A substantial emphasis is placed on the issues of accessibility and equity in public transportation, with a view to exploring how Big Data can inform the provision of equitable services and improve the experiences of users. By critically examining analytical validation processes and the integration of diverse data sources, this research contributes to the ongoing discourse on the role of Big Data in fostering sustainable urban development. The findings demonstrate the potential of Big Data to revolutionise transportation systems, optimise resource allocation, and enhance the quality of life for urban residents. Ultimately, this thesis aspires to provide actionable insights and frameworks that facilitate the effective utilisation of Big Data in creating responsive, resilient, and equitable transportation solutions within Smart Cities
Geochemical record and fe redox evolution of high-pressure serpentinization
No full textThe release of H₂ and CH₄ fluids from subduction-zone-related serpentinization has garnered significant interest for its implications on the deep biosphere, geochemical cycling of elements, and potential as a deep energy resource. However, identifying natural evidence of deep serpentinization in collisional settings remains challenging. This thesis presents new insights into deep serpentinization by studying two natural examples, with a focus on the Monte Maggiore massif in Alpine Corsica. It integrates field and petrographic analyses with high-resolution sampling and geochemical evaluations, including in-situ trace elements, bulk and in-situ boron isotopes (δ11B), and iron isotopes (δ56Fe). Results revealed the presence of multiple serpentine generations along a serpentinization front, indicating various fluid-rock interactions across a wide temperature range, or driven by silica-rich fluids. Geochemical data show a notable decrease in fluid-mobile elements, and a decrease in boron concentrations and δ11B from serpentinites at the basal tectonic contact to the less serpentinized core, reflecting upward migrations of fluids. High Fe3+/FeTot ratios indicate the potential to release reduced fluids. Additionally positive correlation of Fe3+/FeTot with δ56Fe values suggest for input of heavy δ56Fe fluids during serpentinization. The parallel case study Belvidere Mountain Complex (BMC) in Northern Vermont, a high-temperature serpentinized body, shows a decrease in δ56Fe values from partially to fully serpentinized samples, suggesting the influence of lighter iron isotope slab fluids during serpentinization. This thesis emphasizes the use of a cartographic approach and geochemical tracers to identify fluid sources and fluid-rock interaction mechanisms. This provides insights into serpentinization and redox conditions of previously overlooked dry portions of subducted oceanic mantle interacting with slab-derived fluids in subduction. Exploring these themes could enhance our understanding of the magnitude and conditions under which reduced fluids are released in subduction zones, their impact on the deep biosphere, the geochemical cycle of elements, and potential deep energy resources.Il rilascio di fluidi ricchi in H₂ e CH₄ dalla serpentinizzazione in zone di subduzione ha suscitato interesse per le implicazioni sulla biosfera profonda, il ciclo geochimico degli elementi e come potenziale risorsa energetica profonda. Tuttavia, identificare esempi naturali di tale processo in ambienti collisionali rappresenta ancora una sfida. Questa tesi fornisce nuove evidenze di serpentinizzazione profonda tramite due casi studio, con focus sul massiccio di Monte Maggiore in Corsica Alpina, integrando campionamento ad alta risoluzione, petrografia e analisi geochimiche, tra cui isotopi di boro (δ11B) e ferro (δ56Fe). I risultati mostrano più generazioni di serpentino lungo un fronte di serpentinizzazione, suggerendo interazioni fluido-roccia a diverse temperature, o eventualmente mediati da fluidi ricchi di silice. I dati geochimici evidenziano una diminuzione di concentrazione di elementi mobili nei fluidi e una riduzione delle concentrazioni di boro e δ11B dalle serpentiniti verso il nucleo meno serpentinizzato, indicando migrazioni verso l’alto dei fluidi. I rapporti Fe3+/FeTot suggeriscono il rilascio di fluidi ridotti, mentre la correlazione con δ56Fe suggerisce l’apporto di fluidi con valori elevati di δ56Fe durante la serpentinizzazione. Lo studio del Belvidere Mountain Complex nel Vermont, un corpo serpentinizzato ad alta temperatura, mostra una diminuzione di δ56Fe con il grado di serpentinizzazione, indicando l’influenza di fluidi con valori bassi di δ56Fe provenienti dallo slab. Questa ricerca enfatizza l’uso di approcci cartografici e traccianti geochimici per identificare fonti e meccanismi di interazione fluido-roccia. Fornisce nuove evidenze sulle condizioni redox di porzioni anidre del mantello oceanico subdotto che interagiscono con fluidi profondi, con l’obbiettivo di contribuire a migliorare la comprensione delle condizioni di rilascio dei fluidi ridotti nelle zone di subduzione e il loro impatto sulla biosfera profonda, sul ciclo geochimico e sul potenziale ruolo di risorsa energetica
Development of in vitro models for the assessment of drug transfer across the mammary epithelial barrier: from 2D to 3D porcine primary mammary epithelial cell culture
No full textThere is paucity of information about the safe use of drugs during lactation, as clinical studies present ethical and practical challenges. The European project ConcePTION has been working to narrow this huge gap by developing non-clinical in vivo, in vitro and in silico lactation models that can predict drug concentrations crossing the blood-milk barrier. The pig was selected as animal model to conduct lactating experimentation for the physiological affinity with humans, in particular the Göttingen minipigs breed has been preferred for the genetic stability and microbiological control. The present work aimed to develop a minipig mammary epithelial cell (mpMECs) in vitro model to determine the extent of drug transfer into milk. The results described the isolation and characterization of mpMECs. The cells were able to reproducibly form a tight barrier within the first week of culture, with a transepithelial electrical resistance (TEER) profile similar to that obtained with mammary epithelial cells of hybrid pigs. In addition, a human mammary epithelial cell model was developed to evaluate more closely the translatability of the pig/minipig model. The primary human mammary epithelial cells (hMECs) were able to form the epithelial barrier, although measurable TEER values were reached after about 30 days, unlike mpMECs. Furthermore, the mRNA drug transporters expression levels were analyzed and the energetic metabolic profile of both mpMECs and hMECs was also evaluated. Lastly, a 3D multicellular culture model was developed to faithfully recreate a fully blood-milk barrier, by co-culturing mpMECs with two vascular-wall cell populations: the aortic endothelial cells and the mesenchymal stromal cells. In conclusion, a minipig mammary epithelial cell in vitro model to study the medicine partitioning in milk has been defined; the 3D culture model will lay the foundation for a more complex and comprehensive blood-milk barrier model than 2D by improving the Replacement and Reduction
5G & beyond cellular networks for industrial IoT: a cross-layer perspective
No full text5G networks are transforming telecommunications by serving both human and machine communications, enabling new use cases across various industries. As a key enabler for Internet of Things (IoT), 5G provides connectivity to devices that collect and act on data. Within this context, Industrial IoT (IIoT) supports Industry 4.0, improving efficiency and safety of industries by enabling communication between industrial devices. However, this progress introduces significant challenges, as networks must meet the performance, reliability, and scalability requirements dictated by the served applications. To overcome these challenges, this thesis provides solutions based on the industrial applications, the cellular network, and their interplay, including cross-layer approaches. The arguments span the whole protocol stack and focus on the mutual dependence between applications and the supporting network. Novel solutions and methodologies are provided, addressing the challenges of industrial communications to advance future cellular IIoT systems. First, an analysis of cellular networks and IIoT is provided. Next, it is performed a joint analysis of a safety-critical industrial application and the 5G network serving it, highlighting their interplay, and how this affects scalability and reliability. Subsequently, we leverage application-layer data to optimize the Radio Access Network (RAN), enhancing the performance of the served industrial application. Following, to address the growing demand for throughput and reliability in IIoT, Orthogonal Chirp Division Multiplexing (OCDM), a promising waveform for beyond-5G communication, is evaluated. Additionally, Industrial Ethernet protocols and their integration with 5G networks are examined. The findings, derived mainly from simulations and experiments, provide valuable insights on cellular IIoT networks and show improvements over current solutions. These results highlight the importance of adopting a cross-layer approach to meet IIoT requirements and offer guidelines for designing future cellular networks, laying the groundwork for more efficient and reliable industrial systems
Artificial intelligence and advanced statistical methods for predictive modelling in lifestyle improvement and noncommunicable disease prevention
No full textNon-communicable diseases (NCDs), driven by aging populations and behavioral risk factors like poor diet and tobacco use, pose a major global health threat. Innovative prevention strategies are essential to reduce their rising impact on mortality and morbidity. AI and digital health technologies show great promise for NCD prevention, offering accurate risk prediction and personalized interventions. Advances in data-driven methods enhance health monitoring and can significantly support efforts to reduce the global NCD burden. This thesis demonstrates how the Food4HealthyLife (F4HL) project contributes to advancing personalized disease prevention. Led by the University of Bergen in collaboration with the University of Bologna and others, the project aims to develop predictive models for personalized risk estimation based on dietary habits. It also highlights how artificial intelligence, particularly natural language processing (NLP), can enhance these models. The project is structured in three parts: 1. Identification and synthesis of epidemiological evidence for expanding the F4HL suite. Key findings include links between food groups and mortality, diabetes outcomes, and identifying harmful dietary habits in Italians. 2. Validation and development of NLP-based tools to optimize the appraisal of scientific evidence. Key results include the development of TextAlchemy for extracting data from articles and the validation of ASReview’s effectiveness for screening in epidemiological umbrella reviews. 3. Investigation of the habits and attitudes of citizens regarding the use of digital health technologies (DHTs) and their impact on interactions between patients and healthcare professionals (HCPs). Findings reveal age and education influence DHT use and perceptions, with country-specific patterns. Citizen-HCP interactions remain limited but show potential for growth, as many users express interest in more frequent engagement. This work supports integrating AI into research and healthcare, aiming to build an evidence-based suite for personalized lifestyle recommendations. With professional support, its adoption could reduce the global burden of unhealthy habits and NCDs