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Towards a sustainable approach for Cultural Heritage Conservation: developing micro-structured green materials and analytical protocols for their performance assessment
No full textCleaning is one of the most important and delicate procedures that are part of the restoration process. When developing new systems, it is fundamental to consider its selectivity towards the layer to-be-removed, non-invasiveness towards the one to-be-preserved, its sustainability and non-toxicity. Besides assessing its efficacy, it is important to understand its mechanism by analytical protocols that strike a balance between cost, practicality, and reliable interpretation of results.
In this thesis, the development of cleaning systems based on the coupling of electrospun fabrics (ES) and greener organic solvents is proposed.
Electrospinning is a versatile technique that allows the production of micro/nanostructured non-woven mats, which have already been used as absorbents in various scientific fields, but to date, not in the restoration field.
The systems produced proved to be effective for the removal of dammar varnish from paintings, where the ES not only act as solvent-binding agents but also as adsorbents towards the partially solubilised varnish due to capillary rise, thus enabling a one-step procedure.
They have also been successfully applied for the removal of spray varnish from marble substrates and wall paintings. Due to the materials' complexity, the procedure had to be adapted case-by-case and mechanical action was still necessary.
According to the spinning solution, three types of ES mats have been produced: polyamide 6,6, pullulan and pullulan with melanin nanoparticles. The latter, under irradiation, allows for a localised temperature increase accelerating and facilitating the removal of less soluble layers (e.g. reticulated alkyd-based paints).
All the systems produced, and the mock-ups used were extensively characterised using multi-analytical protocols.
Finally, a monitoring protocol and image treatment based on photoluminescence macro-imaging is proposed. This set-up allowed the study of the removal mechanism of dammar varnish and semi-quantify its residues. These initial results form the basis for optimising the acquisition set-up and data processing
Diazene photoswitches in artificial molecular machines and light-effected materials
No full textThe research developed in this thesis focused on the spectroscopic and photochemical characterization of molecular diazene photoswitches, both as individual species and as functional components of mechanically interlocked molecules, molecular-based materials and artificial molecular machines and motors.
Among the plethora of photochromes reported so far, azobenzene is the most versatile photoswitch due to its reproducible and well-established photochemical properties. Part I of this thesis work focuses on the characterization of light-responsive supramolecular systems based on azobenzene: a photochemically-driven rotary motor, a light-responsive supramolecular polymeric material and a supramolecular system capable of photoinduced entantiodiscrimination.
Despite the wide success of azobenzene photoswitches, the tunability of their photochemical properties as a function of the diversified substitution pattern on its aryl ring presents intrinsic limitations. To overcome this issue, in the last decade heteroaryl azoswitches (i.e., azobenzene having heterocyclic rings in place of one or both phenyl groups) have attracted a great deal of attention. Hence, Part II of this thesis work treats the photochemical characterization of two different families of azoheteroarenes embedding imidazolium and thienyl functionalities in their structures. Their potential implementation in water-soluble artificial molecular machines and light-effected semiconductor materials is also assessed
Ex ante contracts to arbitrate tort claims - A law and economics perspective
No full textThis research addresses the use of ex ante contracts to arbitrate tort claims in domestic settings using law and economics research methodologies. Potential economic benefits from using arbitration, particularly between informed and knowledgeable parties and in international business transactions, are not guaranteed in domestic disputes. Arbitration can potentially be used to manipulate the adjudication process. This research has several findings. There is a lack of information available concerning the use of arbitration to adjudicate tort claims. Proxy measurements concerning the demand for third party adjudication and other legal indicators are a poor substitute for the information hidden behind the veil of arbitration. There is the potential for the strategic use of ex ante contracts to arbitrate tort claims by repeat player tortfeasors to domestic tort claims, both individually and in concert with other repeat player firms. These strategic efforts aim to: manipulate enforcement errors for tort claims, avoid procedural rules which have the effect of lowering enforcement errors, enable a unique type of domestic forum arbitrage, shirk from taking due care, capture the economic benefit of using arbitration, manipulate the stock of precedents and production of public goods from courts, collude in these underlying efforts, restrain competition, indirectly fix prices, and other aims which increase the repeat player tortfeasor’s or their industries economic gains related to their underlying contracts and tort disputes. This research also demonstrates how this subject is appropriate for further academic research and why states should be cautious of giving carte blanche to arbitrate all domestic tort claims
AAGL 2021 classification system and risk of surgical complications in women submitted to surgery for endometriosis
No full textIntroduction: Recently, the American Association of Gynecologic Laparoscopists proposed a new classification and scoring system with the specific aim to assess surgical complexity. This study sought to assess if a higher AAGL score correlates with an increased risk of peri-operative complications in women submitted to surgery for endometriosis.
Methods: This is a retrospective cohort study conducted in a third level referral center. We collected data from women with endometriosis submitted to complete surgical removal of endometriosis from January 2019 to December 2021. ENZIAN, r-ASRM classifications and AAGL total score was calculated for each patient. Population was divided in two groups according to the occurrence or not of at least one peri-operative complication. Our primary outcome was to evaluate the correlation between AAGL score and occurrence of complications.
Results: During the study period we analyzed data from 282 eligible patients. Among them, 80 (28.4%) experienced peri-operative complications. No statistically significant difference was found between the two groups in terms of baseline characteristics, except for pre-operative hemoglobin (Hb), which was lower in patients with complications (p=0.001). Surgical variables associated with the occurrence of complications were recto-sigmoid surgery (p=0.003), ileocecal resection (0.034), and longer operative time (p=0.007). Furthermore, a higher ENZIAN B score (p=0.006), AAGL score (p=0.045) and stage (p=0.022) were found in the group of patients with complications. The multivariate analysis only confirmed the significant association between the occurrence of peri-operative complications and lower pre-operative Hb level (OR 0.74; 95% CI, 0.59 - 0.94; p=0.014), longer operative time (OR 1.00; 95% CI, 1.00 – 1.01; p=0.013), recto-sigmoid surgery - especially discoid resection (OR 8.73; 95% CI, 2.18 – 35; p=0.016) and ENZIAN B3 (OR 3.62; 95% CI, 1.46 – 8.99; p= 0.006).
Conclusion: According to our findings, high AAGL scores or stages do not seem to increase the risk of peri-operative complications
Different approaches in regenerative medicine: modulation of biological properties of human mesenchymal stem cells and induction of cardiomyocyte proliferation
No full textThe term “regeneration” defines a process which aims at the re-establishment of the morphological and physiological functions of damaged tissues and organs. The human body uses its own tissue-resident stem cells to repair adult tissues and organs, and to counteract senescence-related processes. Human mesenchymal stem cells show many useful and promising properties, such as self-renewal, multilinear differentiation, and isolation from almost all organs, in the regenerative medicine and cell therapy fields. Unfortunately, the human heart regeneration after injury is almost absent, and scars occurs. Several approaches have been used to improve the regenerative process, such as the use of satellite cells, cardiac stem cells, or other adult stem cells, but the results have been poor. In heart regeneration, the most promising strategy appears to promote the dedifferentiation and re-entry into cell cycle of cardiomyocytes.
The aim of the study was to find new cellular strategies that could be useful in regenerative medicine.
On the one hand, several “well-being” molecules (Leu-enkephalin, Met-enkephalin, β-endorphin, Oxytocin and Cannabidiol) have been tested to evaluate their effects on stem cells isolated from human adipose tissue, trying to reduce their senescence process, and promoting their differential ability. The results obtained indicate that Oxytocin and Cannabidiol were able to modulate the differentiative ability of stem cells (osteogenic and adipogenic, respectively), thus being interesting for the application of stem cells in regenerative medicine.
On the other hand, we tested pro-inflammatory cytokines and growth factors alone or in association to assess the best combination that allowed the de-differentiation and re-enter in cell cycle of neonatal mice cardiomyocytes. Preliminary results showed that the administration of pro-inflammatory cytokines prior the administration of growth factors resulted the best condition to promote cardiomyocyte proliferation. Further investigations need to be assessed to deeply understand the molecular pathways behind our results
Development of innovative systems and indicators fpr sustainable shellfish farming
No full textShellfish farming plays an important role in world aquaculture, with total production being over 25%. It is threatened by climate change. In particular, predictive models show there will be more frequent, intense and lasting heat waves. In this thesis, three shellfish species, the Pacific oyster Magallana gigas, the striped venus clam Chamelea gallina and the Mediterranean mussel Mytilus galloprovincialis, were exposed to a heat wave of 28°C± 0.5°C for 30 days, as predicted for the northern Adriatic in the coming years. Biometric, physiological and hemolymphatic parameters were assessed during the prolonged thermal stress, including heat shock proteins (HSP) 70, 72, 90 and factor p53 gene expression for M. gigas; ability to survive at aerial exposure and the synthesis of HSP70 for C. gallina; performances of the byssus for M. galloprovincialis. During 10 days of high temperature, the M. gigas metabolism is affected by loss in weight, in energy resources, reduction of nutrient absorption and pulp yield, an over-expression of HSPs. This thermal effect could lead to reduced productivity and salable products.
C. gallina, remains slightly affected, using the energy resources of hepatopancreas but increasing the ability to survive at air and inhibiting the synthesis of HSP70. Their remarkable thermal resistance highlights their suitability for shellfish aquaculture. M. galloprovincialis showed an intermediate response compared to the two molluscs mentioned above: no reduction in pulp yield but in the energy resources, air survival, number and strength of byssus with altered structure. These changes could increase the risk of loss of the farmed product, by breaking the byssus that keeps the mussels tied to the nets.
With these studies an attempt has been made to provide tools to understand what to expect about the trend of the shellfish aquaculture in the future in a changing and warming climate
Methodologies for the analysis and interpretation of environmental datasets from areas interested by offshore activities
No full textThe exploitation of hydrocarbon reservoirs by the oil and gas industries represents one of the most relevant and concerning anthropic stressor in various marine areas worldwide and the presence of extractive structures can have severe consequences on the marine environment. Environmental monitoring surveys are carried out to monitor the effects and impacts of offshore energy facilities. Macrobenthic communities, inhabiting the soft-bottom, represent a key component of these surveys given their great responsiveness to natural and anthropic changes. A comprehensive collection of monitoring data from four Italian seas was used to investigate distributional pattern of macrozoobenthos assemblages confirming a high spatial variability in relation to the environmental variables analyzed. Since these datasets could represent a powerful tool for the industrial and scientific research, the steps and standardized procedures needed to obtain robust and comparable high-quality data were investigated and outlined. Over recent years, decommissioning of old platforms is a growing topic in this sector, involving many actors in the various decision-making processes. A Multi-Criteria Decision Analysis, specific for the Adriatic Sea, was developed to investigate the impacts of decommissioning of a gas platform on environmental and socio-economic aspects, to select the best decommissioning scenario. From the scenarios studied, the most impacting one has resulted to be total removal, affecting all the faunal component considered in the study. Currently, the European nations are increasing the production of energy from offshore wind farms with an exponential expansion. A comparative study of methodologies used five countries of the North Sea countries was carried out to investigate the best approaches to monitor the effects of wind farms on the benthic communities. In the foreseeable future, collaboration between industry, scientific communities, national and international policies are needed to gain knowledge concerning the effects of these industrial activities on the ecological status of the ecosystems
Distribuzione tradizionale e online: la duplice distribuzione
No full textEl 10 de mayo de 2022 se publicó el Reglamento (UE) 720/2022 relativo a la aplicación del apartado 3 del artículo 101 del TFUE a determinadas categorías de acuerdos verticales y prácticas concertadas. Entre las novedades más significativas introducidas por el Reglamento se encuentra la regulación de la distribución dual.
La distribución dual es una situación en la que un fabricante decide distribuir sus productos directamente (utilizando sus propios distribuidores) y, al mismo tiempo, contratar a distribuidores independientes (que no tienen ninguna relación de propiedad con el fabricante). En efecto, en la distribución dual, el fabricante compite a dos niveles: por un lado, a nivel de fabricante -compite con otras empresas que fabrican productos potencialmente sustitutivos- y, por otro, a nivel de distribución -compite con distribuidores independientes en la venta de sus productos-. Es en este último nivel donde existe el riesgo de restringir la competencia cuando el fabricante impone restricciones (por ejemplo, precios mínimos u otras condiciones de venta) a sus distribuidores independientes.
En consecuencia, en el presente trabajo se estudia, en primer lugar, la naturaleza del contrato de distribución tanto en el derecho español como en el derecho comparado. En segundo lugar, se analizan las principales cuestiones relacionadas con el modelo de distribución online, en primer lugar, se realiza un estudio exhaustivo de las plataformas digitales o marketplaces, analizando sus características, sus tipos y las partes que intervienen en ellas, en segundo lugar, se examina la posibilidad de calificar el contrato entre las plataformas digitales y el vendedor o prestador de servicios como contrato de distribución, analizando su contenido contractual y su encaje en el Reglamento (UE) 2019/1150. Finalmente, se concluye con una profundización en el sistema de distribución dual, así como un estudio de los intercambios de información que tienen lugar en un sistema de distribución dual.On 10 May 2022, Regulation (EU) 720/2022 on the application of Article 101(3) TFEU to categories of vertical agreements and concerted practices was published. Among the most significant innovations introduced by the regulation is the regulation of dual distribution.
Dual distribution is a situation where a manufacturer decides to distribute its products directly (using its own distributors) and, at the same time, to contract with independent distributors (who have no ownership relationship with the manufacturer). In effect, in dual distribution, the manufacturer competes at two levels: on the one hand, at the manufacturer level - it competes with other companies manufacturing potentially substitute products - and, on the other hand, at the distribution level - it competes with independent distributors in selling its products. It is at the latter level that there is a risk of restricting competition when the manufacturer imposes restrictions (e.g. minimum prices or other sales conditions) on its independent distributors.
Consequently, this work firstly studies the nature of the distribution contract in both Spanish and comparative law. Secondly, the main issues related to the online distribution model are analysed, firstly, an exhaustive study of digital platforms or marketplaces is carried out, analysing their characteristics, their types and the parties involved in them, secondly, the possibility of classifying the contract between digital platforms and the seller or service provider as a distribution contract is examined, analysing its contractual content and how it fits into Regulation (EU) 2019/1150. Finally, it concludes with an in-depth look at the dual distribution system, as well as a study of the information exchanges that take place within a dual distribution system.Il 10 maggio 2022 è stato pubblicato il Regolamento (UE) 720/2022 relativo all'applicazione dell'articolo 101.3, del TFUE a categorie di accordi verticali e pratiche concordate. Tra le novità più significative introdotte dal regolamento vi è quella relativa alla regolamentazione della duplice distribuzione.
La duplice distribuzione è una situazione in cui un produttore decide di distribuire i propri prodotti direttamente (utilizzando i propri distributori) e, allo stesso tempo, di stipulare contratti con distributori indipendenti (che non hanno alcun rapporto di proprietà con il produttore). In effetti, nella distribuzione duale, il produttore compete a due livelli: da un lato, a livello di produttore - compete con altre aziende che fabbricano prodotti potenzialmente sostitutivi - e, dall'altro, a livello di distribuzione - compete con distributori indipendenti nella vendita dei propri prodotti. È a quest'ultimo livello che si corre il rischio di limitare la concorrenza quando il produttore impone restrizioni (ad esempio, prezzi minimi o altre condizioni di vendita) ai suoi distributori indipendenti.
Di conseguenza, il presente lavoro studia innanzitutto la natura del contratto di distribuzione sia nel diritto spagnolo che nel diritto comparato. In secondo luogo, si analizzano le principali questioni relative al modello di distribuzione online, in primo luogo, si effettua uno studio esaustivo delle piattaforme digitali o dei marketplace, analizzando le loro caratteristiche, le loro tipologie e le parti in esse coinvolte, in secondo luogo, si esamina la possibilità di classificare il contratto tra le piattaforme digitali e il venditore o il fornitore del servizio come un contratto di distribuzione, analizzando il suo contenuto contrattuale e come si inserisce nel Regolamento (UE) 2019/1150. Infine, si conclude con un approfondimento sul sistema di duplice distribuzione, nonché con uno studio degli scambi di informazioni che avvengono all'interno di un sistema di duplice distribuzione
New catalysts and strategies for the transformation of bioethanol into fuels and chemicals
No full textThe exploitation of fossil resources has led to a massive release of greenhouse gases and the increase of the earth’s temperature. Additionally, the contention of fossil reservoirs has triggered international conflicts and wars. Bioethanol refinery was identified as a valuable approach to develop a circular economy and fragment fuels and chemicals production, thus reducing global warming and alleviating international tension. In this work, three strategies are presented to upgrade the properties of bioethanol and broaden the domain of biorefinery products.
The Guerbet reaction provides an ideal mechanism for ethanol homologation to butanol and higher alcohols with excellent properties. The catalytic activity of ruthenium-based complexes in the liquid-phase Guerbet reaction is reported. The employment of p-benzoquinones as co-catalysts led to ethanol conversions up to 88%, with a selectivity of 97% for higher alcohols. The catalytic systems can be recycled and show comparable efficiency on real matrices of waste bioethanol.
The gas-phase, continuous flow catalytic upgrading of ethanol is tackled. A simple and cheap catalytic system consisting of copper nanoparticles supported on zirconium (and lanthanum) oxides was found to promote a one-pot cascade reaction scheme leading to the production of a blend of adducts in the C6-C14 range with promising jet fuel properties. By tailoring the features of the non-innocent support and the reaction conditions, up to 40% selectivity for the jet fuel range fraction, with ethanol conversion above 85%, was achieved.
Acetaldehyde is an important commodity and its manufacture currently relies almost exclusively on fossil ethylene. A selection of W-V-O mixed oxide catalysts with hexagonal tungsten bronze structure incorporating alkali and alkaline earth metals was synthesized, characterized, and tested in the gas-phase, continuous flow catalytic aerobic oxidation of ethanol to acetaldehyde. The introduction of Cs in the bronze backbone allowed for the achievement of 33% EtOH conversion and 97% acetaldehyde selectivity
Enhancing autonomous driving vision: deep learning approaches to data synthesis, 3D representation and model efficiency
No full textIn the autonomous driving domain, effectively perceiving and interpreting the environment is crucial for safe and efficient navigation. The field has been revolutionized by deep learning models that enable the vehicle to detect, recognize and segment objects in the surrounding environment. However, several challenges persist, including the time-consuming process of data collection and labeling, inconsistencies in the quality of input data, and the constraint of real-time processing. To address these issues, we present three approaches: the augmentation of training datasets, the refinement of input data during the inference stage, and the transfer of knowledge from complex to lightweight models via a process known as knowledge distillation. We show that generative adversarial networks and attention-based architectures can be leveraged, respectively, to generate realistic samples from a learned data distribution and to increase the input resolution. These methods can improve the generalization capabilities of detection, segmentation, and reconstruction algorithms. Furthermore, a significant contribution of our research is the integration of knowledge distillation, aligning the performance of simpler models with their more complex counterparts. This ensures the perception systems are not only accurate but also versatile in real-time scenarios, a critical aspect for the successful deployment of safe autonomous vehicles