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Publicity owned companies in the electricity market, competition and public service
Get PDFLa disciplina pubblicistica dell’energia elettrica presenta specificità rilevanti rispetto
ad altri settori della regolazione economica. Il settore energetico si caratterizza infatti
per una complessa regolazione, dovuta sia alle specificità dell’oggetto della disciplina,
cioè l’energia elettrica come bene immateriale, sia alla molteplicità degli interessi
pubblici coinvolti, che si innestano su fallimenti di mercato (i.e. il sistema a rete non
duplicabile), sia agli obiettivi di politica internazionale e di sicurezza nazionale, che
intercettano delicate interrelazioni con l’ambiente e il clima, come tutelati nel Green
Deal, nelle normative europee e nazionali e negli accordi internazionali sulla
decarbonizzazione e sullo sviluppo sostenibile. Inoltre, la filiera elettrica è
“verticalmente integrata”, cioè suddivisa in attività diverse, cioè la produzione, il
dispacciamento, la trasmissione, la distribuzione, la vendita all’ingrosso e al dettaglio
di energia. Queste sono esercitate in regimi di mercato differenti: monopolio naturale
(dovuto al carattere sub-additivo dei costi) per il dispacciamento, la trasmissione e la
distribuzione di energia; libera concorrenza per la produzione e la vendita. L’esigenza
di assicurare la concorrenza nel mercato energetico si contempera con la necessità di
rispettare gli obblighi di servizio pubblico, in un delicato bilanciamento tra esigenze
contrapposte. La Direttiva U.E. del 13 luglio 2009 n. 2009/72/Cee, all’art. 3, qualifica
infatti la fornitura di energia elettrica come un servizio universale, attribuendo agli
utenti il diritto di ricevere la fornitura e di mantenere prezzi ragionevoli, facilmente e
chiaramente comparabili, trasparenti e non discriminatori.The public regulation of electricity has significant specificities compared to other
sectors of economic regulation. In fact, the energy sector is characterised by a complex
regulation, due both to the specificity of the object of the discipline, i.e. electricity as
an intangible asset, and to the multiplicity of public interests involved, which are
grafted onto market failures (i.e. the non-duplicable grid system), and to international
policy and national security objectives, which intercept delicate interrelations with the
environment and climate, as protected in the Green Deal, in European and national
regulations and in international agreements on decarbonisation and sustainable
development. Moreover, the electricity supply chain is characterised by being
'vertically integrated', i.e. divided into different activities: production, dispatching,
transmission, distribution, wholesale and retail, carried out under different market
regimes: natural monopoly regime (given the sub-additive nature of the costs) for
dispatching, transmission and distribution; free competition for production and sale.
The need to ensure competition in the energy market is reconciled with the need to
respect public service obligations, in a delicate balancing between opposing
requirements. In fact, the Article 3 of EU Directive of 13 July 2009 No. 2009/72/EC
qualifies the supply of electricity as a universal service, giving users the right to receive
the supply and to maintain reasonable, easily and clearly comparable, transparent and
non-discriminatory prices
Supporting requirement elicitation and ontology testing in knowledge graph engineering
Get PDFKnowledge graphs and ontologies are closely related concepts in the field of knowledge representation. In recent years, knowledge graphs have gained increasing popularity and are serving as essential components in many knowledge engineering projects that view them as crucial to their success. The conceptual foundation of the knowledge graph is provided by ontologies. Ontology modeling is an iterative engineering process that consists of steps such as the elicitation and formalization of requirements, the development, testing, refactoring, and release of the ontology. The testing of the ontology is a crucial and occasionally overlooked step of the process due to the lack of integrated tools to support it. As a result of this gap in the state-of-the-art, the testing of the ontology is completed manually, which requires a considerable amount of time and effort from the ontology engineers. The lack of tool support is noticed in the requirement elicitation process as well. In this aspect, the rise in the adoption and accessibility of knowledge graphs allows for the development and use of automated tools to assist with the elicitation of requirements from such a complementary source of data. Therefore, this doctoral research is focused on developing methods and tools that support the requirement elicitation and testing steps of an ontology engineering process. To support the testing of the ontology, we have developed XDTesting, a web application that is integrated with the GitHub platform that serves as an ontology testing manager. Concurrently, to support the elicitation and documentation of competency questions, we have defined and implemented RevOnt, a method to extract competency questions from knowledge graphs. Both methods are evaluated through their implementation and the results are promising
Data analysis with merge trees
Get PDFToday’s data are increasingly complex and classical statistical techniques need growingly more refined mathematical tools to be able to model and investigate them. Paradigmatic situations are represented by data which need to be considered up to some kind of trans- formation and all those circumstances in which the analyst finds himself in the need of defining a general concept of shape. Topological Data Analysis (TDA) is a field which is fundamentally contributing to such challenges by extracting topological information from data with a plethora of interpretable and computationally accessible pipelines. We con- tribute to this field by developing a series of novel tools, techniques and applications to work with a particular topological summary called merge tree. To analyze sets of merge trees we introduce a novel metric structure along with an algorithm to compute it, define a framework to compare different functions defined on merge trees and investigate the metric space obtained with the aforementioned metric. Different geometric and topolog- ical properties of the space of merge trees are established, with the aim of obtaining a deeper understanding of such trees. To showcase the effectiveness of the proposed metric, we develop an application in the field of Functional Data Analysis, working with functions up to homeomorphic reparametrization, and in the field of radiomics, where each patient is represented via a clustering dendrogram
Applied deep learning and data science with a human-centric and data-centric approach
Get PDFThe term Artificial intelligence acquired a lot of baggage since its introduction and in its current incarnation is synonymous with Deep Learning. The sudden availability of data and computing resources has opened the gates to myriads of applications. Not all are created equal though, and problems might arise especially for fields not closely related to the tasks that pertain tech companies that spearheaded DL.
The perspective of practitioners seems to be changing, however. Human-Centric AI emerged in the last few years as a new way of thinking DL and AI applications from the ground up, with a special attention at their relationship with humans. The goal is designing a system that can gracefully integrate in already established workflows, as in many real-world scenarios AI may not be good enough to completely replace its humans. Often this replacement may even be unneeded or undesirable.
Another important perspective comes from, Andrew Ng, a DL pioneer, who recently started shifting the focus of development from “better models” towards better, and smaller, data. He defined his approach Data-Centric AI.
Without downplaying the importance of pushing the state of the art in DL, we must recognize that if the goal is creating a tool for humans to use, more raw performance may not align with more utility for the final user. A Human-Centric approach is compatible with a Data-Centric one, and we find that the two overlap nicely when human expertise is used as the driving force behind data quality.
This thesis documents a series of case-studies where these approaches were employed, to different extents, to guide the design and implementation of intelligent systems. We found human expertise proved crucial in improving datasets and models. The last chapter includes a slight deviation, with studies on the pandemic, still preserving the human and data centric perspective
Analytical approaches for the measurement of sulfide in biological and pharmaceutical fields
Get PDFHydrogen sulfide (H2S) is a widely recognized gasotransmitter, with key roles in physiological and pathological processes. The accurate quantification of H2S and reactive sulfur species (RSS) may hold important implications for the diagnosis and prognosis of various diseases. However, H2S species quantification in biological matrices is still a challenge. Among the sulfide detection methods, monobromobimane (MBB) derivatization coupled with reversed phase high-performance liquid chromatography (RP-HPLC) is one of the most reported. However, it is characterized by a complex preparation and time-consuming process, which may alter the actual H2S level. Moreover, quantitative validation has still not been described based on a survey of previously published works. In this study, we developed and validated an improved analytical protocol for the MBB RP-HPLC method. Main parameters like MBB concentration, temperature, reaction time, and sample handling were optimized, and the calibration method was further validated using leave-one-out cross-validation (CV) and tested in a clinical setting. The method shows high sensitivity and allows the quantification of H2S species, with a limit of detection (LOD) of 0.5 µM and a limit of quantification (LOQ) of 0.9 µM. Additionally, this model was successfully applied in measurements of H2S levels in the serum of patients subjected to inhalation with vapors rich in H2S.
In addition, a properly procedure was established for H2S release with the modified MBB HPLC-FLD method. The proposed analytical approach demonstrated the slow-release kinetics of H2S from the multilayer Silk-Fibroin scaffolds with the combination of different H2S donor’s concentration with respect to the weight of PLGA nanofiber.
In the end, some efforts were made on sulfide measurements by using size exclusion chromatography fluorescence/ultraviolet detection and inductively coupled plasma-mass spectrometry (SEC-FLD/UV-ICP/MS). It’s intended as a preliminary study in order to define the feasibility of a separation-detection-quantification platform to analyze biological samples and quantify sulfur species
Multi-functional electrocatalysts for CO2 reduction reaction: towards the modulation of selectivity
No full textThe electrocatalytic reduction of CO2 (CO2RR) is a captivating strategy for the conversion of CO2 into fuels, to realize a carbon neutral circular economy. In the recent years, research has focused on the development of new materials and technology capable of capturing and converting CO2 into useful products. The main problem of CO2RR is given by its poor selectivity, which can lead to the formation of numerous reaction products, to the detriment of efficiencies. For this reason, the design of new electrocatalysts that selectively and efficiently reduce CO2 is a fundamental step for the future exploitation of this technology. Here we present a new class of electrocatalysts, designed with a modular approach, namely, deriving from the combination of different building blocks in a single nanostructure. With this approach it is possible to obtain materials with an innovative design and new functionalities, where the interconnections between the various components are essential to obtain a highly selective and efficient reduction of CO2, thus opening up new possibilities in the design of optimized electrocatalytic materials.
By combining the unique physic-chemical properties of carbon nanostructures (CNS) with nanocrystalline metal oxides (MO), we were able to modulate the selectivity of CO2RR, with the production of formic acid and syngas at low overpotentials. The CNS have not only the task of stabilizing the MO nanoparticles, but the creation of an optimal interface between two nanostructures is able to improve the catalytic activity of the active phase of the material. While the presence of oxygen atoms in the MO creates defects that accelerate the reaction kinetics and stabilize certain reaction intermediates, selecting the reaction pathway.
Finally, a part was dedicated to the study of the experimental parameters influencing the CO2RR, with the aim of improving the experimental setup in order to obtain commercial catalytic performances
Characterization of an international tetraploid wheat germplasm including landraces and primitive wheat towards improved resilience to abiotic and biotic stresses and quality
Get PDFThis thesis aimed to characterise two large tetraploid germplasm collections. The Global Durum Panel, involving modern cultivars and landrances and the Tetraploid Global Collection which comprises all the tetraploid wheat subgroups. Two distinct parallel studies were carried out.
The first is focused on the characterisation of both collection for yield and quality related traits. The panel were phenotyped for two consecutive years each. In this phase the following traits were collected: the number of fertile spikelets per spike, the number of fertile florets of central spikelet for the spike-related traits. The following grain related traits were also phenotyped: the thousand kernel weight, the average grain area, average grain length, average grain width, grain brightness, grain redness, grain yellowness. GWAS analysis were performed for each collected trait and major QTLs were subjected to candidate gene analysis. Major QTLs emerging from GWA study were located on chromosome 2A with a strong bibliographic evidence for grain number-related traits such as the fertile spikelet number, the number of fertile florets per central spikelet. On the other hand two evident peaks were detected on chromosomes 6A and 7B for grain size and weight related traits.
The second work was focused on the characterisation of the Global Durum Panel for root system architecture components, namely the root growth angle. GWAS analysis was perfomed and three major QTLs were detected on chromosome 2A, 6A and 7A. These three QTLs all have a bibliographic evidence
Use of a polypropylene prosthetic mesh to support traditional perineal herniorrhaphy in dogs
Get PDFScopo del progetto di dottorato è stato quello di mettere a punto l’utilizzo di una tecnica alternativa, rispetto a quelle riportate in letteratura, per la risoluzione dell’ernia perineale nel cane.
Tale tecnica si propone di risolvere il difetto mediante l’ausilio di una rete protesica in polipropilene
in supporto all’erniorrafia perineale tradizionale, mediante sutura a punti staccati dei muscoli che costituiscono il diaframma pelvico.
Questa procedura risulta meno invasiva per l’animale rispetto alla tecnica che in letteratura viene definita il gold standard, ovvero la trasposizione del muscolo otturatore interno (Shaughnessy and Monnet, 2015), ed altre tecniche traspositive, quali la trasposizione del muscolo semitendinoso (Morello et al., 2015) e del gluteo superficiale (Bellenger & Canfield, 2002), con tempi di recupero postoperatori più rapidi e una gestione più semplice da parte del proprietario, pur mantenendo eccellenti outcomes.
La messa a punto di questa procedura nasce dalla necessità di trovare una tecnica semplice da
eseguire, che determini una chiusura del diaframma pelvico tale da evitare la comparsa di recidive e
minimizzare le complicazioni post-operatorie.
L’intento del progetto è stato di combinare l’erniorrafia perineale tradizionale con l’utilizzo di reti protesiche così da ricostruire il diaframma pelvico con i muscoli deputati a svolgere tale compito e fornire, tramite la rete, un maggiore supporto alla rafia, evitando le trasposizioni muscolari che comporterebbero un intervento più demolitivo e un recupero più lento da parte del paziente.
Sono stati inclusi nello studio 30 cani portatori di ernia perineale, per un totale di 50 ernie, trattati con l’intervento proposto dal progetto. Di ogni caso sono stati raccolti il segnalamento, l’anamnesi, le indagini diagnostiche e i successivi follow up post-operatori considerando le eventuali complicazioni o la comparsa di recidiva dell’ernia.The aim of the PhD's project was to develop the use of an alternative technique, compared to those reported in the literature, for the resolution of perineal hernia in dogs.
This technique aims to solve the defect with the help of a polypropylene prosthetic mesh in support of the traditional perineal herniorrhaphy, by suturing the muscles that make up the pelvic diaphragm with separate stitches.
This procedure is less invasive for the animal than the technique which in the literature is defined as the gold standard, i.e. the transposition of the obturator internus muscle (Shaughnessy and Monnet, 2015), and other transposition techniques, such as transposition of the semitendinosus muscle (Morello et al., 2015) and gluteus superficialis (Bellenger & Canfield, 2002), with faster postoperative recovery times and easier management by the owner, while maintaining excellent outcomes.
The development of this procedure stems from the need to find a simple technique to perform, which determines a closure of the pelvic diaphragm such as to avoid the appearance of recurrences and minimize post-operative complications.
The intent of the project was to combine traditional perineal herniorrhaphy with the use of prosthetic mesh so as to reconstruct the pelvic diaphragm with the muscles assigned to perform this task and provide, through the mesh, greater support to the raffia, avoiding the muscular transpositions which would involve a more demolitive intervention and a slower recovery by the patient.
Thirty dogs with perineal hernia were included in the study, for a total of 50 hernias, treated with the intervention proposed by the project. Reporting, anamnesis, diagnostic investigations and subsequent post-operative follow-ups were collected for each case, considering any complications or the appearance of recurrence of the hernia
Investigation of organic semiconductor/water interfaces for optobioelectronic devices
Get PDFThe thesis investigates the potential of photoactive organic semiconductors as a new class of materials for developing bioelectronic devices that can convert light into biological signals. The materials can be either small molecules or polymers. When these materials interact with aqueous biological fluids, they give rise to various electrochemical phenomena, including photofaradaic or photocapacitive processes, depending on whether photogenerated charges participate in redox processes or accumulate at an interface.
The thesis starts by studying the behavior of the H2Pc/PTCDI molecular p/n thin-film heterojunction in contact with aqueous electrolyte. An equivalent circuit model is developed, explaining the measurements and predicting behavior in wireless mode.
A systematic study on p-type polymeric thin-films is presented, comparing rr-P3HT with two low bandgap conjugated polymers: PBDB-T and PTB7. The results demonstrate that PTB7 has superior photocurrent performance due to more effective electron-transfer onto acceptor states in solution.
Furthermore, the thesis addresses the issue of photovoltage generation for wireless photoelectrodes. An analytical model based on photoactivated charge-transfer across the organic-semiconductor/water interface is developed, explaining the large photovoltages observed for polymeric p-type semiconductor electrodes in water.
Then, flash-precipitated nanoparticles made of the same three photoactive polymers are investigated, assessing the influence of fabrication parameters on the stability, structure, and energetics of the nanoparticles. Photocathodic current generation and consequent positive charge accumulation is also investigated.
Additionally, newly developed porous P3HT thin-films are tested, showing that porosity increases both the photocurrent and the semiconductor/water interfacial capacity.
Finally, the thesis demonstrates the biocompatibility of the materials in in-vitro experiments and shows safe levels of photoinduced intracellular ROS production with p-type polymeric thin-films and nanoparticles.
The findings highlight the potential of photoactive organic semiconductors in the development of optobioelectronic devices, demonstrating their ability to convert light into biological signals and interface with biological fluids
Polycythemia Vera: discovery of liquid biopsy assays aimed at identifying biomarkers related to thrombotic risk
Get PDFLa Policitemia Vera (PV) è una neoplasia mieloproliferativa con un aumentato rischio di trombosi e di progressione verso la Mielofibrosi. L'infiammazione cronica è comunemente osservata nelle neoplasie mieloproliferative, compresa la PV. La rete infiammatoria, tra le varie componenti, comprende le vescicole extracellulari (EVs), che svolgono un ruolo nella comunicazione cellula-cellula. Inoltre, le componenti microbiche circolanti sono state recentemente indicate come potenziali modificatori dell'infiammazione, della coagulazione e dell’emopoiesi in generale.
Qui abbiamo studiato il DNA microbico delle EVs circolanti attraverso.
Sangue periferico e feci sono stati raccolti da pazienti con PV (n=38) e da donatori sani (n=30). Le EVs circolanti derivate da megacariociti (MK) e piastrine (PLT) sono state analizzate mediante citometria a flusso. Dopo l'estrazione del DNA microbico dalle feci e dalle EV isolate, è stata sequenziata la regione V3-V4 del 16S rDNA.
La percentuale di EVs di MK era ridotta nei pazienti con PV rispetto ai donatori sani. Al contrario, la proporzione di EVs di PLT era aumentata. La PV è stata associata anche a una firma del DNA microbico delle EVs isolate con una maggiore diversità e una composizione microbica distinta rispetto alla controparte sana. Nei pazienti con PV c’è una maggiore proporzione di EVs associate al lipopolisaccaride. Il profilo del microbioma intestinale non differiva tra PV e doantori.
Inoltre, l'aumento della proporzione di EVs di MK e la riduzione di EVs di piastre identificavano i pazienti con pregressa trombosi. Le EVs dei pazienti con trombosi erano impoverite di DNA di Staphylococcus ma arricchite di DNA di Actinobacteria e Anaerococcus. Inoltre, questi pazienti avevano livelli più bassi di EVs associate al lipopolisaccaride.
I pazienti con fibrosi midollare avevano una maggiore proporzione di PE-EV ed erano arricchite in DNA di Collinsella e Flavobacterium.
Questi dati possono contribuire a perfezionare la prognosi della PV e a identificare nuovi bersagli farmacologici.Polycythemia Vera (PV) is a myeloproliferative neoplasm with an increased risk of thrombosis and progression to Myelofibrosis. Chronic inflammation is commonly observed in myeloproliferative neoplasms, including PV. The inflammatory network, among other components, includes extracellular vesicles (EVs), which play a role in cell-cell communication. In addition, circulating microbial components have recently been indicated as potential modifiers of inflammation, coagulation and hematopoiesis in general.
Here we studied the microbial DNA of circulating EVs through.
Peripheral blood and feces were collected from patients with PV (n=38) and from healthy donors (n=30). Circulating EVs derived from megakaryocytes (MK) and platelets (PLT) were analyzed by flow cytometry. After extraction of microbial DNA from feces and isolated EVs, the V3-V4 region of 16S rDNA was sequenced.
The proportion of EVs from MK was reduced in patients with PV compared with healthy donors. In contrast, the proportion of EVs from PLT was increased. PV was also associated with a microbial DNA signature of the isolated EVs with higher diversity and distinct microbial composition compared with the healthy counterpart. There is a higher proportion of lipopolysaccharide-associated EVs in patients with PV. The gut microbiome profile did not differ between PV and doantors.
In addition, increased proportion of EVs of MK and decreased EVs of plates identified patients with previous thrombosis. EVs of patients with thrombosis were depleted in Staphylococcus DNA but enriched in Actinobacteria and Anaerococcus DNA. In addition, these patients had lower levels of lipopolysaccharide-associated EVs.
Patients with spinal cord fibrosis had a higher proportion of PE-EVs and were enriched in Collinsella and Flavobacterium DNA.
These data may help refine the prognosis of PV and identify new drug targets