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Stability of highly hydrogenated monolayer graphene in ultra-high vacuum and in air
No full textThe stability of hydrogenated monolayer graphene was investigated via X-ray photoemission spectroscopy (XPS) for two different environmental conditions: ultra-high vacuum (UHV) and ambient pressure. The study is carried out by measuring the C 1s line shape evolution for two hydrogenated samples one kept in the UHV chamber and the other progressively exposed to air. In particular, the sp3 relative intensity in the C 1s core-level spectrum, represented by the area ratio [Formula presented], was used as a marker for the hydrogenation-level. After four months in UHV, it resulted almost unchanged within the experimental uncertainty. Thus, a long-term stability of hydrogenated monolayer graphene was found, that indicates this material as a good candidate for hydrogen (or tritium) storage as long as it is kept in vacuum. On the other hand, the C 1s spectrum of the sample exposed to air shows a significant oxidation. A rapid growth up to saturation of the carbon oxides was observed with a time constant τ = 2.8 ± 1.2 h. Finally, the re-exposure of the oxidised sample to atomic hydrogen was found to be an effective method for the recovery of hydrogenated graphene. The CH stretching mode was measured via electron energy loss spectroscopy as direct footprint of hydrogenated graphene recovery
Seismic cycle-controlled hydrocarbon vertical migration through carbonates in the Ragusa Oil Field (SE Sicily, Italy)
No full textHydrocarbon seepage at the Earth’s surface provides crucial insights into subsurface petroleum systems. This study investigates the role of seismic cycle dynamics in controlling vertical hydrocarbon migration by studying the Ragusa Oil Field, a long-exploited petroleum district in the Hyblean foreland domain of south-eastern Sicily (Italy). Inspired by oil spilling in the area that followed a seismic sequence in February 2016, a multiscale structural analysis was undertaken to explore the relationship between fault activity and oil mobilization. This study integrates mesoscale structural measurements, microstructural analysis of bitumen-bearing fault breccias, and 3D Dilation Tendency modelling under paleo- and present-day stress conditions to build a dynamic model of upward hydrocarbon migration and seepage at the Earth’s surface during the seismic cycle in carbonate-hosted normal faults in a foreland setting. Evidence from abandoned asphalt mines and active seep sites reveals both stratigraphic layer-impregnation and localized fault/fracture-controlled oil pathways. Field observation and Dilation Tendency analysis indicate that vertical hydrocarbon migration may predominantly occur by fractures instability during seismic rupture allowing overpressured fluids to migrate vertically, mainly at fault in- tersections. These findings highlight the role of seismic deformation in controlling fractures instability and transient permeability changes which, in turn, facilitate hydrocarbon mobilization and leakage. Calcite clast aggregates within hydrocarbon-filled voids observed during microstructural investigations confirm episodic, pressure-driven fluidization consistent with co-seismic mobilization. Stratigraphic evidence of repeated seepage events in Quaternary alluvial deposits supports a model of cyclic hydrocarbon migration linked to stress vari- ations during the seismic cycle. The novelty of this paper is that we document an hydrocarbon seepage process associated with modern seismicity, filling the gap of previous observations of hydrocarbon seepage speculatively associated with fossil earthquakes without a direct cause-effect link
Claudiléia Lemes Dias y la representación de personas trans latinoamericanas en Italia
No full textLa condición interseccional de las personas migrantes LGBTQIA+ ha sido objeto de interés creciente en los últimos años, entre otras cosas, porque estas subjetividades encarnan un cuestionamiento de la Modernidad occidental protagonizada, en sus relatos oficiales, por hombres cis heterosexuales. En Italia siguen existiendo estereotipos exotizantes que llevan a la sexualización de personas migrantes procedentes de algunos países de América Latina. El texto propone, como caso de estudio, las narraciones de Claudiléia Lemes Dias, autora brasileña residente en Italia, quien, en algunas de sus narraciones, representa los estereotipos que se encuentran en la sociedad italiana con respecto a las mujeres trans
A green strategy for resveratrol nanodelivery: A multidisciplinary approach for the physicochemical characterization of Thymus-based liposomes with anti-biofilm activity against Listeria monocytogenes
No full textNanocarrier-based drug delivery systems (DDS) offer promising strategies to enhance therapeutic efficacy, stability, and targeted delivery of bioactive compounds while reducing side effects. In this study, a multidisciplinary approach was employed to develop and characterize bioactive liposomes incorporating resveratrol (RV), a polyphenol with known therapeutic potential but limited bioavailability, and Thymus vulgaris essential oil (TEO), recognized for its antimicrobial and antioxidant properties. To obtain stable nanocarriers, liposomes were formulated using soy lecithin and prepared by thin layer evaporation technique followed by sonication process. To assess the preservation of TEO's chemical profile during formulation, Headspace Solid Phase Microextraction coupled with Gas Chromatography–Mass Spectrometry (HS-SPME/GC-MS) was performed. Quantitative analysis of thymol and carvacrol, the two main active components, was performed by HPLC-UV experiments. Physicochemical characterization of DDS was carried out employing Dynamic Light Scattering (DLS), UV–Vis spectrophotometer and Transmission electron microscopy. Antimicrobial activity was assessed by broth microdilution method, while biofilm inhibition ability was evaluated using crystal violet staining. The obtained nanocarriers exhibited appropriate physicochemical characteristics, including optimal particle size and stability. They can efficiently load both oil and RV. These features enhanced the antibacterial activity of LT-RV compared to free RV, and improved its inhibitory effect, at sub-MIC concentrations, against the sessile form of Listeria monocytogenes strains.
This study highlights the importance of integrating chemical, physical, and biological evaluations to develop effective nanocarrier-based formulations with the aim to identify a suitable strategy to combat infections associated with resistant, biofilm-producing pathogens, and offer a versatile and effective delivery platform
Bridging the ESG Asymmetry: Lessons from Climate risk for the Integration of Social and Governance Risks in Banking Supervision
No full textThis study analyses the integration of Environmental, Social and Governance (ESG) risks into banking regulation and supervision, focusing on the persistent imbalance between the advanced treatment of environmental risks and the limited development of social and governance frameworks. While climate-related risks have rapidly been incorporated into supervisory tools and disclosure requirements, social and governance risks remain affected by definitional ambiguity, data constraints and methodological shortcomings.
The research identifies regulatory, informational and methodological gaps that hinder the effective incorporation of these risks into prudential frameworks. It reviews recent European and international regulatory developments, examines the potential contribution of ESG rating agencies, and proposes a stress-testing approach tailored to social and governance risk factors. An empirical application based on existing environmental data illustrates the feasibility of the framework and supports its future extension.
The study contributes to the literature by highlighting the need for a more comprehensive prudential approach to ESG risks in order to ensure banking stability in the medium to long term
Deciphering the impact of a diagnostic/prognostic miR-1, miR-26a-1 and miR-487 signature in the response to treatment in human glioblastomas
No full textGlioblastomas (GBMs) are aggressive brain tumors and challenging cancers for diagnosis and treatment. Therapeutic options include surgery followed by chemotherapy with the DNA alkylator temozolomide (TMZ) and radiotherapy. However, the patient prognosis remains poor due to tumor heterogeneity, cell infiltration and intrinsic or acquired resistance to therapy. Understanding the resistance mechanisms together with identifying new biomarkers are crucial for developing novel therapeutic strategies.
MicroRNAs (MiRNAs) play an important role in the biology of gliomas, modulating tumorigenesis and therapy response. We recently identified the diagnostic/prognostic miR-1-3p, miR-26a-1-3p and miR-487b-3p signature that displays an oncosuppressive role on several glioma biological functions. In this thesis work, we investigated the effects of the therapeutic potential of this three-miRNA signature as regulator of response to TMZ. We found that ectopic expression of the miRNA signature in patient-derived GBM-neurospheres treated with TMZ impaired cell proliferation and viability by necroptosis induction. Moreover, we identified WT1 and FOXA1, two transcription factors specifically involved in TMZ resistance, as novel direct targets of the miRNA signature. Of note, the repression of WT1 and FOXA1, elicited by the signature, caused a downregulation of the Androgen Receptor (AR) expression, an impairment of tumor-spheroid formation and reversed cancer cell stemness. These results were recapitulated using the AR inhibitor Enzalutamide, confirming the involvement of the AR pathway.
Our data indicate that the miR-1-3p/miR-26a-1-3p/miR-487b-3p signature, which has an impact on treatment response and cell stemness, may pave the way for miRNA-based complementary therapies in GBM patients
Innate immune reprogramming in the tumor microenvironment
No full textInnate immune cells within the tumor microenvironment (TME) sense danger, drive inflammation and, depending on their activation state and local cues, can either suppress or support tumor growth. This thesis investigates phenotypic and functional reprogramming of two innate populations—natural killer (NK) cells and mast cells (MCs)—during tumor progression, and defines mechanisms by which the TME shapes their activity.
We demonstrated that, during tumor progression, chronic stimulation of the activating NK receptor NKG2D induces an hypofunctional state characterized not only by NKG2D downregulation but also by impairment of DNAM 1, a receptor critical for tumor cell clearance. By using primary human NK cells exposed overnight to MICA presented by transfectants, or plate bound MICA, we showed increased expression of a checkpoint receptor able to counteract DNAM-1 activation. Stimulation with an agonist antibody directly inhibits DNAM-1-mediated signal transduction and cytotoxic function with a mechanism that required NKG2D endocytosis.
Moreover, by focusing on colorectal cancer (CRC), analysis of fresh biopsies and matched healthy mucosa revealed that tumors are enriched in soluble mediators that sustain MC survival and reprogramming and show an overall increase in MC numbers accompanied by a clear phenotypic shift between healthy mucosa and tumor lesions. Finally, stratification by microsatellite status revealed a subtype-specific polarization of MCs depending on the tumor’s molecular background.
Overall, our findings clarify the molecular mechanisms behind the often controversial roles of innate immune components in tumor progression and pave the way for new therapeutic strategies
From waste to wealth: Can fluidized-bed gasification transform industrial practices?
No full textGasification is emerging as a key technology for producing energy and useful products from waste, while
reducing landfill impact. Among the various gasification technologies, fluidized bed systems have emerged as
particularly suitable for sustainable waste processing, owing to their superior thermal uniformity and ability to
operate at industrial scales. However, the widespread deployment of fluidized bed gasification still faces major
technical, economic, and environmental challenges. Continuous operation is hindered by tar formation and
equipment fouling, a persistent challenge that has remained the primary technological barrier for decades,
driving the need for integrated and advanced mitigation strategies, and bed material agglomeration induced by
ash melting. Additionally, syngas quality can significantly deteriorate when heterogeneous feedstocks are used
without advanced control strategies. The need for complex downstream tar removal systems also undermines the
cost-competitiveness of this technology compared to alternatives for biofuel production. This vision paper does
not aim to provide a comprehensive review of the relevant literature, but rather to synthesize the current state of
the art and project it into the future, with a strong forward-looking perspective intended to guide technological
innovation, industrial development, and policymaking with reference to the European and Chinese perspectives.
Therefore, promising approaches to overcome current limitations are explored, including the development of
energy efficient and economically competitive in situ and ex situ tar mitigation solutions, the implementation of
advanced multivariable control strategies, and the application of machine learning for real-time process optimization. Furthermore, novel reactor designs and schemes are assessed with the goal of intensifying hydrogen
concentration in the syngas and intrinsically minimizing pollutant and tar formation, such as in chemical looping
gasification, sorption-enhanced gasification, and supercritical water gasification. Finally, by integrating recent
experimental results and techno-economic assessments, this work offers a holistic perspective on how fluidized
bed gasification of waste can be scaled up to industrial applications and reach syngas-based synthetic natural gas
costs of below 50 €/MWh
Gli effetti degli inibitori delle 5 alfareduttasi sul metabolismo del glucosio in pazienti affetti da ipertrofia prostatica benigna e diabete mellito di tipo II
No full textIntroduzione: i glucocorticoidi (GC) influenzano significativamente l’omeostasi glucidica. La 5-alfa reduttasi svolge un ruolo chiave nel metabolismo dei GC, facilitandone la clearance. Pertanto, i farmaci inibitori della 5-alfa reduttasi (5ARi), utilizzati comunemente nel trattamento dell’iperplasia prostatica benigna (IPB), potrebbero influenzare negativamente l’omeostasi glucidica.
Obiettivo dello studio: esplorare le correlazioni tra profilo circadiano dei glucocorticoidi e metabolismo glucidico, fornendo un’analisi preliminare sugli effetti metabolici dell’inibizione della 5-alfa reduttasi.
Materiali e metodi: lo studio è osservazionale, prospettico, proof-of-concept, caso-controllo e ha valutato pazienti affetti da IPB in due fasi successive, la prima nel periodo di arruolamento, la seconda dopo circa 3 mesi dall’inizio della terapia con 5ARi o dalla prosecuzione della terapia antecedente. Sono state realizzate le seguenti procedure di studio: analisi del cortisolo salivare (da campioni salivari raccolti in 5 momenti della giornata) mediante tecnica di cromatografia liquida - spettrometria di massa tandem (LC-MS/MS) e cosinor-based analysis, monitoraggio continuo della glicemia interstiziale (CGM) per una durata di 14 giorni, prelievi di sangue venoso per analisi glico-metaboliche e ormonali.
Risultati: tra ottobre 2024 e maggio 2025 sono stati arruolati 22 pazienti. Alla valutazione basale, i parametri del ritmo circadiano del cortisolo hanno mostrato una correlazione significativa con il metabolismo glucidico. Nello specifico, una maggiore ampiezza delle fluttuazioni giornaliere di cortisolo è risultata associata a valori migliori di emoglobina glicata (r= 0.494; P= 0.044) e di glicemia a digiuno (r = 0.502; P = 0.040), oltre che a un miglior pattern CGM in termini di variabilità glicemica (r = 0.900; P <0.001), tempo nel range 70-140 mg/dL (r = 0.598; P = 0.009) e glicemia media (r = 0.431; P = 0.074). È interessante notare come l’esposizione globale al cortisolo, stimata mediante calcolo dell’area sotto la curva (AUC24h) del profilo circadiano del cortisolo salivare, non abbia mostrato correlazioni significative con i parametri di controllo glicemico.
13 pazienti hanno completato la valutazione longitudinale. Un’analisi preliminare ha mostrato un’evoluzione peggiore nel gruppo trattato con 5ARi in termini di ampiezza delle oscillazioni circadiane e di controllo glicemico, sebbene la bassa numerosità campionaria non abbia permesso di raggiungere la significatività statistica.
Conclusioni: lo studio del profilo circadiano del cortisolo mediante LC-MS/MS e l’analisi dei parametri del CGM hanno permesso di realizzare una fine indagine delle correlazioni tra l’attività dei glucocorticoidi e l’omeostasi glucidica. L’associazione tra ridotta pulsatilità della secrezione dei glucocorticoidi e peggiore profilo glicemico, analizzata insieme all’assenza di correlazioni tra l’esposizione globale ai glucocorticoidi e i parametri di controllo glicemico, ha confermato il ruolo centrale della pulsatilità circadiana dei glucocorticoidi nella determinazione del rischio cardiometabolico. Il proseguimento dello studio permetterà di ottenere dati più robusti per la valutazione dell’effetto dei 5ARi su tali correlazioni
Povertà e salario minimo. Il lavoro tramite piattaforma
No full textLa ricerca indaga il fenomeno della povertà nonostante il lavoro e il ruolo del diritto nella regolazione delle dinamiche occupazionali, alla luce delle trasformazioni economiche e sociali che hanno inciso sulla sostenibilità del modello costituzionale del lavoro nella nostra esperienza giuridica. Adottando la prospettiva del diritto privato comparato, la tesi analizza il rapporto tra struttura economica e sovrastruttura giuridica, evidenziando come il diritto, pur incidendo sui comportamenti individuali, non sia sufficiente a modificare i rapporti di forza generati dalle scelte economiche e dalle politiche del mercato del lavoro. Il primo capitolo affronta il tema del “lavoro povero” e la possibile frattura tra Costituzione formale e Costituzione materiale in Italia. Il secondo approfondisce la questione del salario minimo — nelle sue declinazioni legale, giurisprudenziale e contrattuale — con un confronto tra esperienze nazionali ed europee, in particolare quella tedesca. Il terzo capitolo è dedicato al lavoro mediante piattaforma, quale paradigma di un capitalismo flessibile che ridefinisce le categorie tradizionali di subordinazione. L’analisi evidenzia il progressivo indebolimento delle tutele lavoristiche e la necessità di ripensare il ruolo del diritto come strumento di riequilibrio sociale e democratico.The research investigates the phenomenon of in-work poverty and the role of law in regulating employment dynamics, in light of the economic and social transformations that have affected the sustainability of the constitutional model of labour in the Italian legal system. Adopting a comparative private law perspective, the dissertation analyses the relationship between economic structure and legal superstructure, highlighting how law, while influencing individual behaviour, is insufficient on its own to modify the power relations generated by economic choices and labour market policies. The first chapter addresses the issue of “working poverty” and the possible fracture between the formal and material Constitution in Italy. The second chapter examines the question of the minimum wage — in its statutory, judicial, and collectively negotiated forms — through a comparison of national and European experiences, with particular attention to the German case. The third chapter focuses on platform work as a paradigm of flexible capitalism that redefines the traditional categories of subordination. The analysis underscores the progressive weakening of labour protections and the need to reconsider the role of law as a tool for restoring social and democratic balance