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Microbiome-based applications for sustainable food production and waste-streams valorization
Get PDFNatural microbiomes represent an untapped source of functionalities to be used as eco-friendly biofertilizers/pesticides, as well as for the biotransformation of biomasses into platform chemicals and bioactive compounds. In this view, we focused on two main research topics. First, we used Next Generation Sequencing and metagenomics to characterize the microbiome of Vitis vinifera roots – and surrounding soil – across two worldwide famous Italian viticultural sites. We focused on microbial communities at the soil-root interface as a determinant of the wine terroir, with particular emphasis on microbial Plant Growth-Promoting (PGP) functions, as decades of research have demonstrated the role of microbial communities in providing beneficial functions for plant nutrition, growth, and stress tolerance, making them a strategic player for the transition to sustainable agriculture. PGP functions include drought resistance, nitrogen fixation, phosphorus solubilization, exudation of bacterial siderophores, production of antimicrobials, phytohormones, and competition with pathogens and pests. Our results shed light on PGP microorganisms in Italian wine-producing sites, paving the way for implementing new microbiome-based inoculants for wine production aimed to increase product quality and sustainability. The second part of the thesis investigates microbiome-based biotransformation of lignocellulose (LC) into useful molecules. Lignocellulose is the most abundant polymer on Earth and is composed of carbohydrates (cellulose, hemicellulose, and pectin) and aromatic compounds (lignin), holding the potential to be deconstructed for several biotechnological applications, but recalcitrant to hydrolysis. We structurally and functionally explored the gut microbiome (GM) of the Alpine ibex (Capra ibex L.), a wild herbivore from Stelvio National Park, for the metagenomic biodiscovery of microbial species, hubs, and pathways involved in LC biotransformation. We provided glimpses of fecal bacterial strains as a possible solution for the bioconversion of lignocellulose to high-value compounds, such as volatile fatty acids and alcohols, with also a preliminary investigation of their biosynthetic potential
Mathematical models and numerical methods for environmental applications of fast field cycling nuclear magnetic resonance
Get PDFFast Field-Cycling (FFC) Nuclear Magnetic Resonance (NMR) relaxometry is a non-destructive technique operating at low magnetic fields to investigate molecular dynamics and structures in environmental, biological, and food systems, exploring slow dynamics and revealing motion across diverse timescales. Despite its broad applicability, accurately identifying parameters from NMR Dispersion (NMRD) profiles remains a significant computational challenge. This thesis introduces and evaluates advanced inverse methods based on regularization and machine-learning approaches to enhance NMRD analysis. Within the Model-Free framework, NMRD profiles are represented as a linear combination of Lorentzian functions. To tackle the ill-conditioned inverse problem, three regularization methods are validated: (1) MF-UPen, a locally adaptive L₂ regularization; (2) MF-L1, an L₁-penalized approach; and (3) MF-MUPen, a hybrid of local L₂ and global L₁ penalties. Automated selection of regularization parameters via the Balancing and Uniform Penalty principles improves robustness and reproducibility. To model quadrupolar relaxation enhancement (QRE) arising from electric interactions of spin > ½ nuclei, a constrained L₁-regularized non-linear least squares framework is proposed. It decomposes relaxation profiles into dipole-dipole and quadrupolar contributions. The regularization parameter is iteratively computed with the Balancing Principle, and parameters are optimized using a non-linear Gauss–Seidel algorithm. Tests on synthetic and real datasets confirm convergence and effectiveness. A MATLAB tool implementing this method is freely available.
Finally, a machine-learning framework based on Plug-and-Play (PnP) integrates a pre-trained feed-forward neural network into a coordinate-descent optimizer to extract QRE parameters and fit NMRD profiles. Its custom loss balances L₁ loss with quadrupolar prediction accuracy, yielding precise parameter extraction. Experimental validation against traditional inverse methods demonstrates accuracy and efficiency, particularly for large-scale industrial datasets. This work advances the computational toolkit for FFC-NMR relaxometry, offering robust algorithms and machine-learning solutions that deepen understanding of molecular dynamics across diverse systems
NOZZLE and MULSTREG: numerical optimization tools for energy industry - black-box optimization for clean energy technologies
Get PDFIn this work, we study how to exploit Derivative-Free Optimization and Black-Box Optimization in the design and validation phases of a cooling system in a gas turbine. Firstly, we define NOZZLE, a numerical model of a section of the cooling system, and we use an optimization method to obtain an efficient design; secondly, we develop MUℓSTREG: an optimization method to enhance the validation procedures of an entire cooling system. NOZZLE is a Black-Box function that simulates an impingement cooling system for a turbine nozzle starting from a well-known model that correlates the design features of the cooling system with efficiency parameters. The optimization model is defined as a mixed-variable constrained BBO problem and we numerically illustrate how to use DFO algorithms to find a reference solution that is useful for practitioners. MULSTREG is a new multilevel stochastic framework for the solution of optimization problems where the value of the objective function is noisy. We focus on data-fitting problems with random uncertainty as in the validation phase of a complete cooling system in a turbine. The proposed approach uses random regularized first-order models that exploit a hierarchical description of the problem, being either in the variable space or in the function space, allowing different levels of accuracy for the objective function. The convergence analysis of the method is conducted and its numerical behavior is tested on finite-sum minimization problems. The multilevel framework is tailored to the solution of such problems resulting in fact in a nontrivial variance reduction technique with adaptive step-size that outperforms standard approaches when solving nonconvex problems. Our stochastic method does not require the finest approximation to coincide with the original objective function. This allows us to avoid the evaluation of the full sum in finite-sum minimization problems, opening to the solution of large classification problems
Measuring, hedging, and mitigating climate risk in financial markets and environmental resources
Get PDFThis thesis investigates the interaction between climate risk and financial markets, focusing on transition risk, physical risk, and their implications for asset pricing and hedging. Transition risk, stemming from the economic adjustments required to address climate change, is inherently challenging to quantify due to its reliance on regulatory and market dynamics. The study examines potential proxies, including European carbon allowance returns and a transition risk index, to measure transition risk in stock and bond markets. However, both proxies were found statistically insignificant, indicating limited sensitivity of financial markets to these variables or their inadequacy as measures of transition risk. Physical risk, caused by climate-related extreme events, demonstrated a more substantial influence on bond market pricing. A novel pricing model incorporating climate variables into the stochastic hazard rate framework was proposed, allowing for the assessment of physical risk exposure. This approach provided actionable insights for ranking corporate issuers based on their sensitivity to physical risk factors. The thesis also explores weather derivatives as hedging instruments for climate risk. For temperature-based derivatives, a market-aligned pricing model was introduced by defining a tradable "forward temperature" asset, addressing inefficiencies in existing methods. Despite these advances, the market for temperature derivatives remains underdeveloped, with significant underpricing. Additionally, innovative derivative contracts, such as Rainfall Quanto Options and Basin Level Cash-or-Nothing Options, were proposed to hedge water scarcity risks. These tools demonstrated effectiveness in addressing geographic and market limitations, offering flexibility beyond traditional insurance mechanisms. By analyzing the integration of climate risks into financial markets and proposing novel hedging instruments, this work provides valuable insights for policymakers, asset managers, and financial institutions to better assess, manage, and mitigate the financial impacts of climate change
Analysis and optimization of low-emission technologies: the cases of chemical looping dry reforming and adsorptive vapor recovery
Get PDFHydrogen and syngas demand has seen a dramatic rise in the last years, but their conventional fossil-based production processes are associated with high CO2 emissions. As such, new approaches are needed to achieve greater process sustainability. Current and novel production technologies are here extensively reviewed, with greater focus on the chemical looping reforming technology using CeO2 based carriers. The experimental evaluation of four different oxygen carriers for methane reforming is here presented: a natural chromite mineral, pure CeO2, a 50% mol CeO2-CuO mixture and 30% w Al2O3-CeO2 mixture. The Al2O3-CeO2 carrier showed enhanced performance compared to the pure CeO2 carrier when regenerated in either 3%vol O2 or 15%vol CO2 flows, with H2 and CO yields of 2.9±0.5 and 1.5±0.3 mmol/gCeO₂ and 41±6% CH4 conversion in the former condition, and H2 and CO yields of 2.80±0.01 and 1.35±0.04 mmol/gCeO₂, and 31.6±0.3% CH4 conversion in the latter. A first attempt at modeling the process for CeO2 carrier was carried out using Aspen AdsorptionTM software. Toxic emissions are also a critical concern for process sustainability, with volatile organic compounds being persistent and highly toxic environmental pollutants. Fugitive emissions from storage tanks are a severe source of risk for the workers, the population and the environment around such plants, as well as a significant loss of valuable products. In the second part of the present elaborate, the main technologies available for abatement of volatile organic compounds are discussed, with a greater focus on adsorption. An extensive review of data for adsorption of hydrocarbons is performed for zeolite, activated carbon and silica adsorbents. An Aspen AdsorptionTM simulation is performed to assess the behavior of activated carbon multicomponent adsorption columns. Bed height and diameter play the greatest role in determining column performance (power law relationship) while regeneration pressure and purge flowrate have a more limited effect
The KM3NeT experiment: methods for time, position and pointing calibration of the detector
Get PDFNeutrino astronomy is an emerging field in astroparticle physics, focused on measuring astrophysical neutrino fluxes and identifying their sources to better understand cosmic ray origins and acceleration mechanisms. Neutrinos, due to their lack of electric charge and since they interact solely via the Weak interaction, can travel vast distances across the Universe without being absorbed or deflected by magnetic fields, making them ideal probes of high-energy astrophysical phenomena. Their detection is achieved by neutrino telescopes, placed deep underwater or under ice. Since the early precursors, started in the 1970s, significant progresses have been made and the second generation of detectors is now being deployed. The development of this thesis has been carried out within the KM3NeT experiment, which consists in two underwater detectors, KM3NeT/ARCA and KM3NeT/ORCA, under installation and taking data in the depths of the Mediterranean Sea. Recently, the KM3NeT Collaboration has announced the detection with KM3NeT/ARCA of KM3- 230213A, the most energetic cosmic neutrino observed so far, demonstrating the capabilities of the detector even in a partial configuration. At completion, the two detectors are going to reach an overall volume greater than 1 km3 of sea water instrumented with thousands of optical sensors arranged in vertical strings. To reach the desired performances in terms of angular resolution on the reconstructed direction of neutrinos, the calibration of the detector plays a crucial role. The key parameters to optimize in order to improve the angular resolution are the time synchronization of the optical sensors and the precise determination of their position. Moreover, the correct pointing of the detector and the evaluation of its accuracy is pivotal in order to search for point-like neutrino sources. This thesis presents methods for timing, position, and pointing calibration of the detector, crucial to achieve the scientific goals of the KM3NeT experiment
Rhetorical-argumentative strategies in the renewable energy debate: theoretical aspects and applications
Get PDFL’elaborato proposto ha il duplice obiettivo di descrivere il dibattito sulle energie rinnovabili nei giornali e nelle riviste italiani tra il 2021 e il 2022 e di fornire riflessioni per migliorare l’efficacia comunicativa e persuasiva sull’argomento. Per giungere a tali scopi analitici e applicativi si è adottato un metodo misto, di tipo quali-quantitativo. Lo studio combina elementi propri della corpus linguistics ad ana-lisi linguistico-discorsive, focalizzandosi su dispositivi linguistici impiegabili nel campo retorico-argomentativo quali i frame, le strutture concessive, le dissociazioni, le scelte lessicali e le figure retoriche, presenti all’interno di un corpus di 1000 artico-li. Dall’analisi emergono sia le specifiche modalità retorico-argomentative associate alle strutture, sia gli usi di queste ultime da parte dei partecipanti al dibattito.The objective of this paper is twofold: to analyze the debate on renewable energies in Italian newspapers and magazines between 2021 and 2022 and to propose reflections for enhancing communicative and persuasive effectiveness on the topic. To pursue these analytical and practical goals, a mixed-method approach was adopted, integrating qualitative and quantitative methodologies. The study combines elements of corpus linguistics with linguistic and discursive analyses, focusing on rhetorical-argumentative linguistic devices such as frames, concessive structures, dissociations, lexical choices and rhetorical figures, examined within a corpus of 1000 articles. The analysis highlights both the specific rhetorical-argumentative patterns associated with these structures and their use by participants in the debate
Bridging the global-local divide: navigating cultural sustainability in urban heritage management
No full textCultural sustainability is increasingly recognized as a key dimension of global sustainability, particularly in the context of preserving cultural heritage amid urbanization, political shifts, and environmental change. Although integrated into international agendas such as the UN Sustainable Development Goals (SDGs), cultural sustainability often remains fragmented and less developed compared to its social, economic, and environmental counterparts. This research explores how cultural sustainability is interpreted and implemented in two UNESCO World Heritage cities: Venice and Amsterdam. These cases offer distinct yet comparable insights into the tensions and strategies involved in managing urban heritage today. The study addresses a key gap between high-level cultural sustainability frameworks, such as those promoted by UNESCO, and their on-the-ground application in heritage governance. While international discourse emphasizes the importance of cultural heritage, the actual translation of these ideals into urban policies remains inconsistent and contested. Through a qualitative, interpretive approach, this study investigates local decision-making processes and policy implementation, with particular attention to how cities balance heritage preservation with broader urban challenges, such as affordable housing, mass tourism, and climate adaptation. Venice, analyzed through the Horizon 2020 UNCHARTED project, exemplifies the risks of inaction, as it faces possible inclusion on the UNESCO List of World Heritage in Danger. In contrast, Amsterdam serves as a comparative case to examine how global norms “travel” and adapt locally, providing an example of more proactive integration of heritage into urban planning. By comparing these two cases, the research highlights both shared challenges and divergent approaches to cultural sustainability. Ultimately, the findings underscore the importance of context-sensitive strategies and institutional flexibility in implementing cultural sustainability, offering practical insights for policymakers, heritage professionals, and urban planners navigating the complexities of heritage in dynamic urban environments
Yshir-chamacoco feather art in Guido Boggiani's collection at the “Museo delle Civiltà” in Rome: a story of wonder and oblivion
No full textL’intenzione dell’elaborato è quella di indagare il collezionismo etnografico di Guido Boggiani, inquadrandolo nel contesto della nascita della cosiddetta antropologia italiana nelle ultime decadi dell’Ottocento. Osservando alcune figure chiave della temperie culturale e scientifica che suscitò la nascita delle discipline demoetnoantropologiche, ci si focalizza poi sulla specifica figura di Guido Boggiani: pittore, esploratore, fotografo ed etnografo. Leggendo la letteratura da lui prodotta, si entra nel vivo delle sue esperienze etnografiche, introducendo poi il gruppo indigeno yshir-chamacoco da cui gli artefatti di arte plumaria provengono. La seconda parte del testo esplora la geografia, l’etnostoria e parte della cosmovisione indigena per passare poi all’analisi di alcuni esemplificativi artefatti di plumaria.Il testo è corredato di un catalogo di alcuni oggetti esaminati.The aim of this paper is to investigate Guido Boggiani's ethnographic collecting, placing it in the context of the emergence of so-called Italian anthropology in the last decades of the 19th century. After observing some key figures in the cultural and scientific climate that gave rise to the disciplines of demo-ethno-anthropology, we then focus on the specific figure of Guido Boggiani: painter, explorer, photographer, and ethnographer. Reading the literature he produced, we delve into his ethnographic experiences, then introduce the indigenous Yshir-Chamacoco group from which the feather art artifacts originate. The second part of the text explores the geography, ethnohistory, and part of the indigenous worldview, before moving on to the analysis of some exemplary feather art artifacts. The text is accompanied by a catalog of some of the objects examined
Théorie des ensembles de foncteurs dérivés
No full textThis thesis investigates how set theory interacts with the study of derived functors, algebraic tools used to measure how far a functor is from being exact. It focuses on the derived functors of the inverse limit and Ext, both expressible as quotients from certain cohomological complexes. Set theory contributes in two main areas: infinite combinatorics and descriptive set theory. In the combinatorial part, cocycles in derived limits of inverse systems of abelian groups correspond to “coherent” families of functions exhibiting local behavior, while coboundaries express that this behavior holds globally. Thus, derived functors capture a form of incompactness, the gap between local and global properties. The thesis establishes several consistency results about such incompactness for systems indexed by various ideals of sets. The methods include forcing, combinatorial principles of the Constructible Universe (such as Diamond and Square), and properties of cardinal invariants of the continuum. The second line of work connects set theory to descriptive set theory and the theory of Polish modules and modules with a Polish cover. The thesis studies injective and projective objects in the category of pro-Lie Polish abelian groups and analyzes the Borel complexity of the trivial submodule of Ext(C,A), viewed as a module with a Polish cover when A and C are countable flat modules over a countable Dedekind domain. This corresponds to the potential Borel complexity of isomorphism among short exact sequences with fixed end terms. Using a hierarchy of subfunctors indexed by countable ordinals, the thesis defines higher analogues of injective and projective modules and shows that a countable flat module over a countable Dedekind domain that is not injective remains non-injective for all higher analogues