Non-standard signatures from Cosmic Microwave Background polarisation

In this Thesis we focus on non-standard signatures from CMB polarisation, which might hint at the existence of new phenomena beyond the standard models for Cosmology and Particle physics. With the Planck ESA mission, CMB temperature anisotropies have been observed at the cosmic variance limit, but polarisation remains to be further investigated. CMB polarisation data are important not only because they contribute to provide tighter constraints of cosmological parameters but also because they allow the investigation of physical processes that would be precluded if just the CMB temperature maps were considered. We take polarisation data into account to assess the statistical significance of the anomalies currently observed only in the CMB temperature map and to constrain the Cosmic Birefringence (CB) effect, which is expected in parity-violating extensions of the standard electromagnetism. In particular, we propose a new one-dimensional estimator for the lack of power anomaly capable of taking both temperature and polarisation into account jointly. With the aim of studying the anisotropic CB we develop and perform two different and complementary methods able to evaluate the power spectrum of the CB. Finally, by employing these estimators and methodologies on Planck data we provide new constraints beyond what already known in literature. The measure of CMB polarisation represents a technological challenge and to make accurate estimates, one has to keep an exquisite control of the systematic effects. In order to investigate the impact of spurious signal in forthcoming CMB polarisation experiments, we study the interplay between half-wave plates (HWP) non-idealities and the beams. Our analysis suggests that certain HWP configurations, depending on the complexity of Galactic foregrounds and the beam models, significantly impacts the B-mode reconstruction fidelity and could limit the capabilities of next-generation CMB experiments. We provide also a first study of the impact of non-ideal HWPs on CB.

Caratterizzazione di membrane inorganiche per la separazione di idrogeno da gas di reforming

The work of this thesis has been focused on the characterisation of inorganic membranes for the hydrogen purification from steam reforming gas. Composite membranes based on porous inorganic supports coated with palladium silver alloys and ceramic membranes have been analysed. A brief resume of theoretical laws governing transport of gases through dense and porous inorganic membranes and an overview on different methods to prepare inorganic membranes has been also reported. A description of the experimental apparatus used for the characterisation of gas permeability properties has been reported. The device used permits to evaluate transport properties in a wide range of temperatures (till 500°C) and pressures (till 15 bar). Data obtained from experimental campaigns reveal a good agreement with Sievert law for hydrogen transport through dense palladium based membranes while different transport mechanisms, such as Knudsen diffusion and Hagen-Poiseuille flow, have been observed for porous membranes and for palladium silver alloy ones with pinholes in the metal layer. Mixtures permeation experiments reveal also concentration polarisation phenomena and hydrogen permeability reduction due to carbon monoxide adsorption on metal surface.

On land management: landowners' attitudes to land and farming in Valdera, Tuscany

This thesis aims at explaining the intersecting dynamics of structural changes in agriculture and urbanisation, which involves changes in urban-rural relationships. The research questions are: how and why do landowners differ in their attitudes to land and farming? what are the main implications on rural landscapes and the policy implications? Relationships between urbanisation and agriculture are firstly analysed through a critical literature review; the analysis focuses on the 'landowner' as the key actor who actively takes decisions on the rural landscape From the empirical study – which is based on a Tuscan area (Valdera), and addressed through qualitative methods – a great diversity of landowners' attitudes to land and farming emerge, thus contributing to the agricultural restructuring, such as: 1) the emphasis on recreational function of the countryside for urban people 2) contracting out of land management, especially when landowners live or/and have 'urban' employment 3) the active role of hobby farmers in land management 4) agricultural operations simplification and lack of investments (especially in case of property rights expropriation). The thesis is framed in three papers, with the same methods and research questions. It seems evident that rural landscapes is subjected to functional changes (e.g. residential) and structural changes (landscape polarisation), which requires the need 1) to consider that rural landscape management is increasingly less connected to agricultural production as economic activity; 2) to give a coherence to the range of policy interventions (physical planning, landscape, sectoral).

Consumismo virtuoso? Il rapporto tra politica e consumi in Italia negli anni Settanta

Attraverso l’analisi di riviste femminili, d’attualità e di intrattenimento, fonti raccolte in archivi d’impresa (Eni e Fiat) e fonti legate al mondo pubblicitario, questa tesi vuole indagare il rapporto tra politica e consumo in Italia durante gli anni Settanta. L’analisi è partita dallo studio della crisi petrolifera del 1973, le politiche di austerità e le loro conseguenze sui costumi e i consumi, per poi estendere lo sguardo fino agli anni Ottanta, il decennio definito della “svolta edonistica”. L’analisi delle fonti ha fatto emergere come la sfera del consumo fosse un campo di confronto politico per diverse componenti della società italiana, che appoggiarono o misero in discussione, con modalità e gradi di radicalità differenti, le valutazioni sull’accesso ai consumi proprie della classe politica. I casi studio hanno fatto emergere come sui temi dell’educazione al consumo e l’accesso all’informazione ci sia stato un confronto risultato in una formalizzazione istituzionale, diventata dominante, dell’azione e dei diritti di consumatori e consumatrici. Analizzare questi meccanismi ci permette di complicare la lettura evitando una polarizzazione che veda il consumatore o come totalmente passivo e senza autonomia di pensiero o come investito di un’eccessiva possibilità di azione e di una idealizzata carica progressista. Nel corso degli anni Settanta, infatti, le visioni e prospettive sulla sfera del consumo erano molteplici e complesse e si intrecciavano con l’attualità politica, sia per quel che riguardava gli scandali e le polemiche legate alla élite politica ed economica, sia per quel che concerneva dibattiti come quello sul ruolo della donna nella società e sulla questione ambientale. L’analisi di alcune di queste narrazioni sia problematizza il rapporto tra democrazia e benessere, sia mostra alcune tappe del percorso che ha portato alle definizioni odierne di consumo e consumatore, che sono ancora oggi centrali nel rapporto tra sfera politica e sfera del consumo.

The EU’s foreign policy towards the Western Balkans during the Juncker Commission. The cases of Bosnia Herzegovina and Serbia.

In February 2018, four years after the President of the Commission Jean Claude Juncker explicitly deprioritised the enlargement dossier, the European Commission relaunched the enlargement strategy to the region of the Western Balkans. This occurred despite the persistent polarisation around the topic among the EU Member States and the still-present struggles, when not outright regression, of some of the countries in pursuing the demanded reforms. This thesis carries out a multilevel foreign policy analysis of EU foreign policy toward the region of the Western Balkans during the period of the Juncker Commission, through the cases of Bosnia Herzegovina and Serbia. Drawing from Actorness theory (Bretherton and Vogler 2006), combined with perspectives from new institutional leadership (Smeets and Beach 2020), and new intergovernmentalism (Moravcsik 2018; Bickerton et al. 2015), this study seeks to explain the relaunch of enlargement by examining three dimensions: the international context and the role of non-EU actors such as China, Russia, and Turkey; the EU context, through the interaction of the significant EU Member States and Institutions; finally, the local context, through the analysis of the changes in the local perception of the EU and the considered non-EU actors. This study posits two interconnected points: first, that the changes in the international context, specifically the increased presence of non-EU actors such as China, Russia, and Turkey in the region, acted as triggering factors for the relaunch of the strategy. In addition, it argues that this relaunch was successful due to the peculiar combination of Germany’s interests and leadership within the Council, coupled with the Commission’s priorities.