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Spectral asymptotic properties of semi-regular non-commutative harmonic oscillators
Get PDFThe study carried out in this thesis is devoted to spectral analysis of systems of PDEs related also with quantum physics models. Namely, the research deals with classes of systems that contain certain quantum optics models such as Jaynes-Cummings, Rabi and their generalizations that describe light-matter interaction.
First we investigate the spectral Weyl asymptotics for a class of semiregular systems, extending to the vector-valued case results of Helffer and Robert, and more recently of Doll, Gannot and Wunsch. Actually, the asymptotics by Doll, Gannot and Wunsch is more precise (that is why we call it refined) than the classical result by Helffer and Robert, but deals with a less general class of systems, since the authors make an hypothesis on the measure of the subset of the unit sphere on which the tangential derivatives of the X-Ray transform of the semiprincipal symbol vanish to infinity order.
Abstract Next, we give a meromorphic continuation of the spectral zeta function for semiregular differential systems with polynomial coefficients, generalizing the results by Ichinose and Wakayama and Parmeggiani.
Finally, we state and prove a quasi-clustering result for a class of systems including the aforementioned quantum optics models and we conclude the thesis by showing a Weyl law result for the Rabi model and its generalizations
Design and characterization of wideband Hall current sensors in BCD technology for smart power and metering applications
Get PDFPower electronic circuits are moving towards higher switching frequencies, exploiting the capabilities of novel devices to shrink the dimension of passive components. This trend demands sensors capable enough to operate at such high frequencies. This thesis aims to demonstrate through experimental characterization, the broadband capability of a fully integrated CMOS X-Hall current sensor in current mode interfaced with a transimpedance amplifier (TIA), chip CH09, realized in CMOS technology for power electronics applications such as power converters. The system exploits a common-mode control system to operate the dual supply system, 5-V for the X-Hall probe and 1.2-V for the readout. The developed prototype achieves a maximum acquisition bandwidth of 12 MHz, a power consumption of 11.46 mW, resolution of 39 mArms, a sensitivity of 8 % /T, and a FoM of 569-MHz/A2mW, significantly
higher than current state-of-the-art.
Further enhancements were proposed to CH09 as a new chip CH100, aiming for accuracy levels prerequisite for a real-time power electronic application. The TIA was optimized for a wider bandwidth of 26.7 MHz with nearly 30% reduction of the integrated input referred noise of 26.69 nArms at the probe-AFE interface in the frequency band of DC-30 MHz, and a 10% improvement in the dynamic range. The expected input range is 5-A. The chip incorporates a dual sensing chain for differential sensing to overcome common mode interferences. A novel offset cancellation technique is proposed that would require switching of polarity of bias currents. Thermal gain drift was improved by a factor of 8 and will be digitally calibrated utilizing a new built-in temperature sensor with a post calibration measurement accuracy greater than 1%. The estimated power consumption of the entire system is 55.6 mW. Both prototypes have been implemented through a 90-nm microelectronic process from STMicroelectronics and occupy a silicon area of 2.4 mm2
User scheduling for low earth orbit multi-user multiple-input-multiple-output non-terrestrial network systems
Get PDFIn rural and isolated areas without cellular coverage, Satellite Communication (SatCom) is the best candidate to complement terrestrial coverage. However, the main challenge for future generations of wireless networks will be to meet the growing demand for new services while dealing with the scarcity of frequency spectrum. As a result, it is critical to investigate more efficient methods of utilizing the limited bandwidth; and resource sharing is likely the only choice. The research community’s focus has recently shifted towards the interference management and exploitation paradigm to meet the increasing data traffic demands.
In the Downlink (DL) and Feedspace (FS), LEO satellites with an on-board antenna array can offer service to numerous User Terminals (UTs) (VSAT or Handhelds) on-ground in FFR schemes by using cutting-edge digital beamforming techniques. Considering this setup, the adoption of an effective user scheduling approach is a critical aspect given the unusually high density of User terminals on the ground as compared to the on-board available satellite antennas. In this context, one possibility is that of exploiting clustering algorithms for scheduling in LEO MU-MIMO systems in which several users within the same group are simultaneously served by the satellite via Space Division Multiplexing (SDM), and then these different user groups are served in different time slots via Time Division Multiplexing (TDM).
This thesis addresses this problem by defining a user scheduling problem as an optimization problem and discusses several algorithms to solve it. In particular, focusing on the FS and user service link (i.e., DL) of a single MB-LEO satellite operating below 6 GHz, the user scheduling problem in the Frequency Division Duplex (FDD) mode is addressed. The proposed State-of-the-Art scheduling approaches are based on graph theory. The proposed solution offers high performance in terms of per-user capacity, Sum-rate capacity, SINR, and Spectral Efficiency
Essays in political and gender economics
Get PDFIn the first chapter, “Political power and the influence of minorities: theory and evidence from Italy”, I analyze the relationship between minority and majority in politics, and how it can influence policy outcomes. I first present a theoretical model describing the possible consequences of an increase in a minority’s political power and show how it can increase difficulties in reaching a compromise on policy outcomes between parties. Furthermore, I empirically test these implications by exploiting the introduction in 2012 of a gender quota in Italian local elections: the increase in female politicians had heterogeneous effects on the level of funding for daycare, based on its differential effects on the share of women councillors.
The second chapter, “Marriage patterns and the gender gap in labor force participation: evidence from Italy”, presents evidence highlighting a new possible determinant of the large gender gap in the Italian labor force: endogamy intensity. I argue that endogamy helps preserve social norms stigmatizing working women and reduces the probability of divorce, which disincentivizes women’s participation in the labor force. Endogamy is proxied by the degree of concentration of its surnames’ distribution, and I provide evidence that a more intense custom of endogamy contributed to enlarging gender participation gaps across Italian municipalities in 2001.
The third chapter, “Information and quality of politicians: is transparency helping voters?”, studies how voting choices are affected by giving voters more personal information on candidates. I exploit the introduction of the “Spazzacorrotti” law in Italy in 2019, which imposed candidates at local elections to publish their CVs and criminal records before elections. I find no effects on elected candidates’ age, gender, educational level, or ideology. Moreover, I present anecdotal evidence that candidates with a criminal record received fewer votes on average, but only in the case of local media exposing it
Identification of molecular biomarkers in esophageal adenocarcinoma
Get PDFEsophageal adenocarcinoma (EAC) is a severe cancer that has been on the rise in Western nations over the past few decades. It has a high mortality rate and the 5-year survival rate is only 35%–45%. EAC has been included in a group of tumors with one of the highest rates of copy number alterations (CNAs), somatic structural rearrangements, high mutation frequency, with different mutational signatures, and with epigenetic mechanisms. The vast heterogeneity of EAC mutations makes it challenging to comprehend the biology that underlies tumor onset and development, identify prognostic biomarkers, and define a molecular classification to stratify patients. The only way to resolve the current disagreements is through an exhaustive molecular analysis of EAC. We examined the genetic profile of 164 patients' esophageal adenocarcinoma samples (without chemo-radiotherapy). The included patients did not receive neoadjuvant therapies, which can change the genetic and molecular composition of the tumor. Using next-generation sequencing technologies (NGS) at high coverage, we examined a custom panel of 26 cancer-related genes. Over the entire cohort, 337 variants were found, with the TP53 gene showing the most frequent alteration (67.27%). Poorer cancer-specific survival was associated with missense mutations in the TP53 gene (Log Rank P=0.0197). We discovered HNF1alpha gene disruptive mutations in 7 cases that were also affected by other gene changes. We started to investigate its role in EAC cell lines by silencing HNF1alpha to mimic our EAC cohort and we use Seahorse technique to analyze its role in the metabolism in esophageal cell. No significant changes were found in transfected cell lines. We conclude by finding that a particular class of TP53 mutations (missense changes) adversely impacted cancer-specific survival in EAC. HNF1alpha, a new EAC-mutated gene, was found, but more research is required to fully understand its function as a tumor suppressor gene
Biological age markers in Parkinson's disease : results from epigenomic and glycomic analyses
Get PDFLa malattia di Parkinson è una malattia neurodegenerativa caratterizzata da una progressiva disfunzione motoria e cognitiva. È noto che l'età avanzata è il principale fattore di rischio per la malattia di Parkinson e alcuni studi hanno dimostrato un'accelerazione dell'età biologica nelle fasi più avanzate della malattia.
Questo studio si propone di valutare se l'accelerazione dell'invecchiamento biologico descritta nelle fasi avanzate della malattia di Parkinson caratterizzi anche le prime fasi della malattia. A tal fine sono stati utilizzati due tipi di marcatori biologici di età, basati sull'analisi della metilazione del DNA del sangue (l'orologio epigenetico e sue varianti) e dei profili degli N-glicani nel plasma (GlycoAge Test). I biomarcatori sono stati valutati in campioni ottenuti da pazienti con malattia di Parkinson de novo, con diagnosi recente e non ancora in trattamento farmacologico, nonché da pazienti con stadi più avanzati della malattia e da controlli sani. I risultati ottenuti nelle prime fasi della malattia non mostrano segni di invecchiamento accelerato, che trovano conferma nelle fasi più avanzate.
Dai dati di metilazione è possibile prevedere le proporzioni delle diverse popolazioni di leucociti. Questa analisi nelle prime fasi della malattia ha già evidenziato significative alterazioni che seguono in parte quelle caratteristiche dell'invecchiamento del sistema immunitario, suggerendo un'immunosenescenza accelerata nella malattia di Parkinson.
Infine, i dati sulla metilazione del DNA sono stati analizzati per identificare le differenze nelle regioni metilate del genoma tra pazienti con malattia di Parkinson e controlli. I risultati suggeriscono l'esistenza di piccole ma significative alterazioni nella metilazione del DNA che caratterizzano lo stadio precoce e/o avanzato della malattia.
In conclusione, questo studio suggerisce che le prime fasi della malattia di Parkinson sono caratterizzate da specifiche alterazioni epigenetiche e invecchiamento precoce del sistema immunitario, che tuttavia non si traducono in un'alterazione dei biomarcatori di invecchiamento epigenetici e glicomici.Parkinson's disease is a neurodegenerative disease characterized by progressive motor and cognitive dysfunction. Advanced age is known to be the main risk factor for Parkinson's disease, and some studies have demonstrated an acceleration of biological age in the more advanced stages of the disease.
This study aims to evaluate whether the acceleration of biological aging described in the advanced stages of Parkinson's disease also characterizes the early stages of the disease. To this end, two types of biological age markers were used, based on the analysis of blood DNA methylation (the epigenetic clock and its variants) and of N-glycan profiles in plasma (GlycoAge Test). Biomarkers were evaluated in samples obtained from patients with de novo Parkinson's disease, with a recent diagnosis and not yet under drug treatment, as well as from patients with more advanced stages of the disease and from healthy controls. The results obtained at the early stages of the disease do not show signs of accelerated aging, which are confirmed in the more advanced stages.
From the methylation data it is possible to predict the proportions of different leukocyte populations. This analysis in the early stages of the disease has already highlighted significant alterations that partially follow those characteristics of the aging of the immune system, suggesting an accelerated immunosenescence in Parkinson's disease.
Finally, DNA methylation data were analyzed to identify differences in methylated regions of the genome between Parkinson's disease patients and controls. The results suggest the existence of small but significant alterations in DNA methylation that characterize the early and/or advanced stage of the disease.
In conclusion, this study suggests that the early stages of Parkinson's disease are characterized by specific epigenetic alterations and premature aging of the immune system, which however do not translate into an alteration of epigenetic and glycomic biomarkers of aging
European naturalism in the theatre: a study of the relationship between the novel and the stage
Get PDFLe travail de recherche se focalise sur l'étude de l'adaptation de romans naturalistes pour le théâtre. Phénomène largement répandu au XIXe siècle, les adaptations pour le théâtre promettaient la gloire aux romanciers qui tentaient une carrière littéraire. Par ailleurs, ils ont marqué une poussée vers un renouveau du théâtre lui-même sous toutes les formes possibles : interprétation, scénographie, thèmes. Pour cette raison, une étude comparative de plusieurs auteurs naturalistes européens (Zola, Goncourt, Capuana, Lemonnier, Galdós, Hardy) permet de construire un cadre général et d'identifier des pratiques communes. Par ailleurs, l'analyse effectuée au cours de la recherche met également en évidence des tendances socio-littéraires significatives, emblématiques de la construction d'une société capitaliste et démocratique en Europe ouvrant la voie au XXe siècle.This research work focuses on the study of the adaptation of naturalist novels for the theatre. A widespread phenomenon in the XIX century, adaptations for the theatre promised glory to novelists attempting a literary career. Moreover, they marked a shift towards a renewal of the theatre itself in all possible ways: acting, staging, and themes. For this reason, a comparative study of several European naturalist authors (Zola, Goncourt, Capuana, Lemonnier, Galdós, Hardy) makes it possible to build a wide general picture and identify common practices. Furthermore, the analysis carried out during the research also highlights significant socio-literary trends emblematic of the construction of a capitalist and democratic society opening the way to the XX century
Applying machine learning: a multi-role perspective
Get PDFMachine (and deep) learning technologies are more and more present in several fields. It is undeniable that many aspects of our society are empowered by such technologies: web searches, content filtering on social networks, recommendations on e-commerce websites, mobile applications, etc., in addition to academic research. Moreover, mobile devices and internet sites, e.g., social networks, support the collection and sharing of information in real time. The pervasive deployment of the aforementioned technological instruments, both hardware and software, has led to the production of huge amounts of data. Such data has become more and more unmanageable, posing challenges to conventional computing platforms, and paving the way to the development and widespread use of the machine and deep learning. Nevertheless, machine learning is not only a technology. Given a task, machine learning is a way of proceeding (a way of thinking), and as such can be approached from different perspectives (points of view). This, in particular, will be the focus of this research. The entire work concentrates on machine learning, starting from different sources of data, e.g., signals and images, applied to different domains, e.g., Sport Science and Social History, and analyzed from different perspectives: from a non-data scientist point of view through tools and platforms; setting a problem stage from scratch; implementing an effective application for classification tasks; improving user interface experience through Data Visualization and eXtended Reality. In essence, not only in a quantitative task, not only in a scientific environment, and not only from a data-scientist perspective, machine (and deep) learning can do the difference
The first Italian publishing house for feminist children's literature: the picture books of "Dalla parte delle bambine" by Adela Turin
Get PDFLa presente tesi di dottorato propone uno studio sulla casa editrice “Dalla parte delle bambine” di Adela Turin. Attiva dal 1975 al 1982 a Milano, si tratta della prima impresa editoriale femminista per l’infanzia in Italia. Nonostante l’originalità e il successo internazionale dei suoi libri, è stata riscontrata una sorprendente scarsità di studi sull’argomento. Questa ricerca interdisciplinare si propone quindi di colmare questa lacuna, inserendosi nel vivace ambito dello studio della letteratura per l’infanzia in prospettiva di genere.
La dissertazione è divisa in cinque capitoli, a cui si aggiunge un’appendice iconografica che raccoglie le copertine dell’intero catalogo di DPDB.
Nel primo capitolo viene introdotto il quadro teorico della ricerca, dalla complessità della letteratura per il giovane pubblico all’indagine in ottica di genere. Il secondo capitolo si concentra sulle pubblicazioni per bambine e bambini negli anni Settanta, passando in rassegna innovative esperienze editoriali nonché l’opera di scrittori e scrittrici sensibili alle questioni di genere.
La terza sezione si occupa di ricostruire il profilo biografico di Turin e il suo decennale impegno contro il sessismo veicolato dai libri per l’infanzia, per poi concentrarsi sulla storia, il catalogo, la diffusione e la ricezione di DPDB. Il quarto capitolo propone un’analisi qualitativa e quantitativa di un corpus di 20 albi illustrati scritti da Turin, oltre a un confronto fra questi libri e diverse ricerche sulla rappresentazione di genere, allo scopo di evidenziare la peculiarità delle proposte di DPDB.
La quinta sezione, infine, si occupa del rapporto con la contemporaneità. Dopo aver tracciato un quadro della complessa situazione dell’educazione di genere in Italia e aver proposto una panoramica di esperienze editoriali per il giovane pubblico attente alle questioni di genere, quest’ultima parte indagherà i contesti in cui gli albi di Turin vengono oggi letti e consigliati, offrendosi come narrazione alternativa e tutt’ora attuale.This doctoral dissertation investigates the history and production of "Dalla parte delle bambine” (Milan, 1975-1982) by Adela Turin, the first Italian feminist publishing house for children’s literature. Despite its originality and international success, there is a surprising dearth of studies on this subject. This interdisciplinary research, therefore, aims to fill this gap, engaging with the thriving field of the study of children's literature from a gender perspective.
The dissertation is divided into five chapters, plus an iconographic appendix collecting the covers of the entire catalog of "Dalla parte delle bambine."
The first chapter introduces the theoretical framework of the research, reflecting on both the complexity of literature for young people and the specific investigation of children's books from a gender perspective. The second chapter reconstructs the stimulating context of publications for girls and boys in the 1970s in Italy, reviewing innovative publishing experiences as well as the work of gender-sensitive writers.
The third part addresses the central topic of the project: after reconstructing the biographical profile of Turin and her decades-long commitment against sexism conveyed by children's books, this section focuses on the history, catalog, circulation, and reception of “Dalla parte delle bambine." The fourth chapter offers a qualitative and quantitative analysis of 20 picturebooks written by Turin, as well as a comparison between these books and various investigations on gender representation in children’s literature, with the aim of highlighting the distinctiveness of the publishing house's proposals.
Finally, the fifth section deals with the contemporary reception. After addressing the complicated situation of gender education in Italy and examining recent feminist, militant, or gender-positive publishing experiences for young readers, this last part will investigate the contexts in which Turin's books, particularly the re-editions of the 2000s, are now read, being recommended as still-relevant alternative narrations
Pathogenetic mechanisms of gastrointestinal symptoms in a mouse model of Fabry disease: insights on the microbiota-gut-brain axis
Get PDFFabry disease (FD), X-linked metabolic disorder caused by a deficiency in α-galactosidase A activity, leads to the accumulation of glycosphingolipids, mainly Gb3 and lyso-Gb3, in several organs. Gastrointestinal (GI) symptoms are among the earliest and most common, strongly impacting patients’ quality of life. However, the origin of these symptoms and the exact mechanisms of pathogenesis are still poorly understood, thus the pressing need to improve their knowledge. Here we aimed to evaluate whether a FD murine model (α-galactosidase A Knock-Out) captures the functional GI issues experienced by patients. In particular, the potential mechanisms involved in the development and maintenance of GI symptoms were explored by looking at the microbiota-gut-brain axis involvement. Moreover, we sought to examine the effects of lyso-Gb3 on colonic contractility and the intestinal epithelium and the enteric nervous system, which together play important roles in regulating intestinal ion transport and fluid and electrolyte homeostasis.
Fabry mice revealed visceral hypersensitivity and a diarrhea-like phenotype accompanied by anxious-like behavior and reduced locomotor activity. They reported also an imbalance of SCFAs and an early compositional and functional dysbiosis of the gut microbiota, which partly persisted with advancing age. Moreover, overexpression of TRPV1 was found in affected mice, and partial alteration of TRPV4 and TRPA1 as well, identifying them as possible therapeutic targets. The Ussing chamber results after treatment with lyso-Gb3 showed an increase in Isc (likely mediated by HCO3- ions movement) which affects neuron-mediated secretion, especially capsaicin- and partly veratridine-mediated. This first characterization of gut-brain axis dysfunction in FD mouse provides functional validation of the model, suggesting new targets and possible therapeutic approaches. Furthermore, lyso-Gb3 is confirmed to be not only a marker for the diagnosis and follow-up of FD but also a possible player in the alteration of the FD colonic ion transport process