Cryoablation of para-Hisian and mid-septal accessory pathways: long-term outcome of a specific cryoablation protocol

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Advances in Quantum Nonlinear Optics: a nonclassical journey from the optimization of silicon photomultipliers for Quantum Optics to quantum second-harmonic generation

In this thesis, we present our experimental and theoretical work on modern and old topics of Nonlinear Quantum Optics. The thesis is structured as follows. In the first chapter, we provide a general introduction about the basis of this field, in particular about the main concepts and results that will be needed in the following. In the second and third chapters, we explain our research on the role of silicon photomultipliers in Quantum Optics experiments. After a specific characterization of the sensors, we used them to detect nonclassical states of light. Different strategies for the estimation of experimental quantities are suggested. In the fourth chapter, we propose our quantum description for the second-harmonic-generation process, based on well-known perturbative methods. After a general introduction on the state of the art, we immediately dive into the problem by explaining the employed methods and showing our analytical results. Finally, we resume the essence of our achievements and draw our conclusions

Ecological factors affecting the whale shark occurrence in Djibouti and presence of contaminants in the trophic web

Djibouti is an important site where the whale shark (Rhincodon typus Smith 1828) regularly aggregates. Sharks gathering off the Djibouti coast are mostly juvenile males and target dense concentrations of zooplankton. However, only few studies has been carried out, leaving a knowledge gap on the main aspects of the whale shark ecology. Therefore, the main outcome of this study is to determine the environmental factors influencing the presence and distribution of this species in Djibouti. A robust understanding of the spatiotemporal distribution is required for developing successful management strategies for the whale shark protection in this area. Moreover, whale sharks may be potentially exposed to relatively high levels of contaminants in Djibouti since they aggregate along one of the world busiest shipping route. Although the massive release of pollutants in African marine ecosystems and the deleterious effects on biota and humans, at present almost nothing is known about the contamination status of the Gulf of Aden, including Djibouti. The scarcity of studies includes all trophic levels, therefore, with a bottom-up approach, starting from zooplankton to get to predatory shark species, this study aims to characterize the trophic chain from an ecotoxicology point of view. With global decline in shark numbers, evaluating the extent of contaminant exposure is an urgent aspect since anthropogenic pollution may exasperate the current situation. Furthermore, since elasmobranchs are component of the artisanal fishery in Djibouti, and seafood consumption is as an important source of contamination for humans, this study aims to estimate for the first time the exposure health risks derived from shark consumption

Universae Gothorum gentes Romano sese imperio dediderunt. Profili dei rapporti romano-gotici nel IV sec. d.C.

The paper analyzes the particularly problematic political, juridical-legislative and cultural situation of the period between 350 A.D. and 410 AD about, coinciding with the great migrations of the barbarian populations (especially the Gothic ones) within the borders of the Roman Empire and placing as a thematic and temporal center of gravity, the Foedus Gothicum of 382 A.D. In this context, the scientific target pursued is to identify and distinguish, if it’s possible, which legislative provisions and which literary works, produced in conjunction with the aforementioned migrations of peoples, were in causal, direct or indirect relationship, with the same relocations; which imperial constitutions were the expression of the legislative, pro-barbaric or anti-barbaric, policy of the imperial chancelleries (especially under Valente, Theodosius and his direct successors) and which coeval philosophical-literary works, on the other hand, showed the social and cultural perception of this situation and of the consequent imperial Gothic politics

Structural, thermal and functional characterization of metal-organic frameworks containing poly(pyrazolates)-based ligands for carbon dioxide adsorption

The dissertation proposes a comprehensive and systematic study of five new families of bis(pyrazolate) metal-organic frameworks (MOFs) for post-combustion CO2 capture and sequestration (CCS). Chapter I introduces the reader to the renowned problem of global warming, with a special focus on the role of CO2 and the different technologies for post-combustion CCS. MOFs state of the art in CO2 adsorption and the essential properties they should possess to be efficient in this application conclude the Chapter. Chapter II, after an overview on the use of pyrazolate-based MOFs, collects the syntheses of the studied compounds. The structural and thermal characterizations are reported in Chapter III. Chapter IV discusses the textural and adsorption properties, focusing on the influence of the different ligand functionalization. A comparison between the studied MOFs and the literature ones is then reported. Finally, starting from the most performing bis(pyrazolates) in terms of CO2 capacity and affinity, a series of mixed-ligand MOFs (MIXMOFs) is presented to further elucidate the role of linker functionalization in CO2 adsorption. MIXMOFs syntheses and full solid-state characterization are collected in Chapter V together with their CO2 adsorption capacity, affinity and selectivity. MIXMOFs performances are then compared to those of state-of-the-art materials developed for CO2 capture

Characteristics and processes of SMEs internationalization: from opportunities and constraints towards the development of strategic networks

The current thesis aims to provide a comprehensive outlook on the small and medium-sized enterprises’ (SMEs) internationalization-related phenomena, by advancing a gradual approach, setting the state-of-the-art as a building block and then passing to the in-depth analysis of underlying issues through articulate empirical studies. In line with this overall approach, the three chapters composing the thesis address three main research objectives: RO1. to identify and discuss the opportunities and constrains apposite for SMEs internationalization process, laying emphasis on the EU context; RO2. to investigate in-depth the influence of the managerial mindset (i.e., the global mindset versus the psychic distance) on the international business performance of SMEs; RO3. to fathom the relational design and methodology of knowledge sharing within SMEs strategic networks as a prerequisite of innovative performance. Accordingly, Chapter 1 theoretically investigates the opportunities and vulnerabilities apposite for SMEs, insisting on the internationalization conditions, and then empirically exploring the European initiatives meant to support them. Chapter 2 discusses two different facets of the internationalization strategies of SMEs, that is, the roles of psychic distance and global mindset within managerial dyadic collaborations. Chapter 3 approaches the affiliation of SMEs to strategic networks which have emerged as a fruitful path towards knowledge sharing with a view to enhance their innovative performance

Statistical analysis of Dynamic Light Scattering data: from the Schätzel formulas to new approaches based on multi−tau Photon Counting Histogram and variance methods

Dynamic Light Scattering (DLS) is an optical technique aimed at the determination of the dimensions of small particles in a suspension in a range of diameters from about 1 nm to 1 μm. It consists in the measurement, at a fixed angle, of the scattered intensity radiation that, because of the Brownian motion of the particles, fluctuates stochastically with time. A DLS experiment provides the correlation function of the received intensity which is dependent from the coherence time of the fluctuations, that is related to the hydrodynamical radius of the particles that constitute the sample. In this thesis work, we analyzed the error bars associated to a correlation function and proposed a new approach for the analysis of Dynamic Light Scattering data based on multi-tau Photon Counting Histogram and variance methods. We obtained the following results and future perspectives. Statistical analysis of Dynamic Light Scattering data The first goal of this work consists in the analytical determination of the error bars associated to a correlation function. This problem has been analyzed by K. Schätzel in the 1990s. He provided two analytical expressions for the covariance matrix and the variance for the specific case of a Lorentzian spectrum where the correlation function is characterized by a single exponential decay. These formulas do not include the effects due to a triangular averaging and are consequently inaccurate for sampling times higher or similar than the coherence time. In this work, we analyzed these formulas and worked out two exact analytical expressions in which the effects due to the triangular averaging are corrected to all orders. By the use of extensive computer simulations and experimental test carried out on dilute dispersions of calibrated latex spheres, we have shown that the new formula for the variance works quite accurately for sampling times both higher and lower than the coherence time and can be applied well beyond the specific case of a single exponential decay auto-correlation function. We believe that these new covariance and variance formulas would turn out to be a fairly useful tool for the wide community of scientists working in the field of DLS. Nowadays, this technique is ubiquitously based on the use of multi-tau correlators, where, if not properly taken into account, the triangular averaging would introduce huge errors in the estimates of the uncertainties to be associated to the measured correlation function. Photon Counting Histogram applied for the analysis of Dy- namic Light Scattering data The second goal of this thesis work consists in the analysis of a second method for performing particle sizing. In this case the coherence time of the intensity fluctuations will not be recovered from a correlation, but from a series of histograms of the photon counts detected over different integration times. It represents, once normalized, the probability distribution to detect a discrete number of photon counts over a given sam- pling time. In my work we applied the Photon Counting Histogram (PCH) technique for the analysis of DLS data and we analyzed, for a monodisperse sample, the combined use of these two techniques and the advantages it gives with respect to a single one. This technique has been developed for the first time by E. Gratton for the analysis of fluorescent data. His theory works when the sampling time is much smaller than the coherence time. By using the PCH method for the analysis of DLS data, because of the raw data has been taken with the multi-tau method, we analyzed different histograms generated with different sampling times which are both higher and lower than the co- herence time. Moreover, we exploited an alternative method to perform particle sizing by recovering the hydrodynamical diameter by fitting not the histograms themselves, but the variances of the photon count distributions recovered stage by stage as a func- tion of the sampling time. We believe that both the PCH method and the variance analysis applied to DLS data may be useful because they provide a different technique to perform particle sizing, which can work independently from the auto- (or cross-) correlation functions. Both these three techniques can work in parallel and, if they provide the same result, it can be a further proof or cross-check for the correctness of the recovered hydrodynamical diameter of the considered sample

Mortars: a complex material in cultural heritage. A multi-analytical procedure to characterize historical mortars.

This thesis deals with the identification of mortars composition in a cultural and historical context. In detail, the main concern was to collect information for proposing an analytical procedure able to define the mortar typology, balancing advantages, drawbacks, time and costs. In addition, several new techniques have been recently introduced in conservation science and the aim of this research is also to consider these new competences too. To understand the interactions between components of mortars, in Chapter 1 a general overview of the subject is given with a description of the materials and of the historical background, based on the review of the large bibliography taken into account. In Chapter 2 the methods used for the preparation of the model samples and the final composition are explained. Moreover, the analytical techniques used in this research (optical microscopy and petrographic analysis, powder X-ray diffraction, infrared spectroscopy, Raman spectroscopy, environmental scanning electron microscopy, thermal analysis, mercury intrusion porosimetry and computed tomography) are described, specifying the setting of the instruments. In Chapter 3 the results of the characterization of the raw materials and of the model samples are shown, the most meaningful results are shown for each technique. The discussion of the experimental data is presented in Chapter 4, and some analytical protocols are proposed, described and explained. In the last chapter, Chapter 5, the conclusions and the future development of this research are underlined

Genetic abnormalities as diagnostic and prognostic markers in B cell lymphomas: role of new molecular technologies in personalized medicine for extranodal diffuse large B cell lymphoma (EN-DLBCL) and follicular lymphoma (FL)

A plethora of molecular biomarkers are available nowadays in the field of cancer research. However, it is crucial to understand when and how they can be integrated into the clinical setting, translating experimental results from bench to bedside, with the aim of improving patients’ care. We decided to investigate the role of some of these biomarkers in two subtypes of non-Hodgkin lymphoma which still represent a challenge for both researchers and clinicians. We started from diffuse large B cell lymphomas (DLBCLs), investigating a multicentric series of primary extranodal DLBCLs. Overall, data analysis provided strong evidence that the distribution of immunophenotypic, cytogenetic and survival characteristics is site-dependent. We next moved to follicular lymphoma (FL). The translocation (14;18), leading to BCL2 protein overexpression, is considered the genetic hallmark of FL. We tested the incidence of BCL2 negative FLs in a series of Italian patients from the Insubric region, concluding that BCL2 rearrangement in FL is not as frequent as generally reported and that the genetic landscape of FL is more complex than previously thought. What we learned is that even within an individual clinical entity, there is considerable heterogeneity with respect to genetic alterations, expression of commonly assayed markers and, most important, outcome. The personalized approach acknowledges this complexity and gives us tools for the continuous improvement of patients’ care

Health-related outcomes of educational mismatch: evidence from the Russian Federation

This PhD Dissertation aims at contributing to the existing literature on health outcomes of educational mismatch and contains a set of studies which raise the question whether different types of educational mismatch affect objective and subjective measures of health and adverse health behaviors represented by drinking habits. The analysis is applied to the context a LMIC country - the Russian Federation - and conducted on the basis of the Russia Longitudinal Monitoring Survey (RLMS-HSE). The first Chapter of this Dissertation investigates the impact of the vertical type of educational mismatch – overeducation and undereducation - on hypertension and self-reported health of the Russian labour force. The second Chapter considers the impact of overeducation and undereducation on the physical and psychological components of general health, proxied by pain and anxiety (EQ-5D metrics) and the health-related reporting styles of the Russian employees. Finally, the third Chapter investigates the impact of different types of educational mismatch - overeducation, undereducation and horizontal (field-of-study) mismatch - on alcohol use and alcohol consumption in Russia, along with defining potential channels for transmission of this effect by means of conducting a mediator analysis. Overall, the results of the studies included in this Dissertation provide evidence that educational mismatch affects the health outcomes, health-related reporting styles and drinking behaviors of the Russian employees. However, the direction and the magnitude of these effects are gender-specific and vary with the types of educational mismatch considered