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em AMS Tesi di Laurea - Alm@DL - Università di Bologna


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Cloud services are becoming ever more important for everyone's life. Cloud storage? Web mails? Yes, we don't need to be working in big IT companies to be surrounded by cloud services. Another thing that's growing in importance, or at least that should be considered ever more important, is the concept of privacy. The more we rely on services of which we know close to nothing about, the more we should be worried about our privacy. In this work, I will analyze a prototype software based on a peer to peer architecture for the offering of cloud services, to see if it's possible to make it completely anonymous, meaning that not only the users using it will be anonymous, but also the Peers composing it will not know the real identity of each others. To make it possible, I will make use of anonymizing networks like Tor. I will start by studying the state of art of Cloud Computing, by looking at some real example, followed by analyzing the architecture of the prototype, trying to expose the differences between its distributed nature and the somehow centralized solutions offered by the famous vendors. After that, I will get as deep as possible into the working principle of the anonymizing networks, because they are not something that can just be 'applied' mindlessly. Some de-anonymizing techniques are very subtle so things must be studied carefully. I will then implement the required changes, and test the new anonymized prototype to see how its performances differ from those of the standard one. The prototype will be run on many machines, orchestrated by a tester script that will automatically start, stop and do all the required API calls. As to where to find all these machines, I will make use of Amazon EC2 cloud services and their on-demand instances.

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In questo lavoro di tesi sono state sviluppate reazioni domino, tandem e procedure one-pot per ottenere eterocicli enatioarricchiti. Lo sviluppo di queste metodologie sintetiche è molto importante perché permettono di ottenere molecole complesse partendo da prodotti semplici, senza effettuare ripetuti passaggi di purificazione (stop-and-go or step-by-step synthesis). Lo scopo di questo lavoro è di ottenere derivati tetraidrofuranici modificati e derivati ossoazzolinici enantioarrichiti tramite reazioni SN2-Michael o tramite reazioni aldolica-ciclizzazione-Michael usando la catalisi asimmetrica a trasferimento di fase (PTC). Come catalizzatori PTC per imprimere enantioselezione sono stati utilizzati sali di ammonio quaternario derivati dagli alcaloidi della Cinchona. Sono state ottimizzate le condizioni di reazione (base inorganica, temperatura, solvente, tempo di reazione) per i diversi substrati presi in considerazione. I prodotti target sono stati ottenuti con buone rese, ottime diastereoselezioni ma con bassa enantioselezione. I risultati ottenuti richiedono un’ulteriore ottimizzazione e dovranno essere valutate variazioni strutturali dei nucleofili utilizzati. In this thesis were developed domino, tandem reactions and one-pot procedures to obtained enantioenriched heterocycles. The development of these methodologies is very fundamental because they allow to obtain complex molecules starting from raw materials, without carrying out repeated purification steps (stop-and-go or step-by-step synthesis). The purpose of this work is to obtain enantioenriched tetrahydrofuran and oxazoline derivatives through a SN2-Michael reaction or a aldol- cyclization-Michael reaction using the phase-transfer asymmetric catalysis (PTC). For imprint enantioselection we used Cinchona alkaloids quaternary ammonium salts derivatives. The reaction conditions (inorganic base, temperature, solvent, reaction time) were optimised for the different substrates taken into account. The target products were obtained with good yields, excellent diastereoselections but with low enantioselections. The obtained results require further optimization and structural changes in the nucleophiles used must be evaluated.

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In this thesis, I have chosen to translate from Italian into Arabic Canto I of the Inferno, from Dante Alighieri’s epic poem the Divine Comedy (La Divina Commedia) because it’s a masterpiece in both Italian and world literature. Also I have selected it for its artistic value and the universal themes that it depicts. In fact, my purpose in translating this great work into Arabic is to extol the cultural and universal aspects that can be common to human beings everywhere. My paper is written in Arabic and has six sections: A brief introduction on Dante’s life, an introduction to the Divine Comedy, a summary of Canto 1 of the Inferno and its analysis, Canto I of the Inferno in Italian, its translation into Arabic and finally a comment on the translation. The first part -a summary of Dante’s life was presented. The second part of my paper is an introduction to the Divine Comedy, the allegorical epic poem, consisting of three parts: The Inferno (Hell), Purgatorio (Purgatory), and Paradiso (Paradise). The third part is a summary and analysis of Canto 1 of the Inferno, Dante’s most renowned verses. The analysis of Canto highlights the everlasting conflict of man– sinning and giving in to temptation but then trying to repent and search for his soul’s salvation. He reflects on sin, existence, truth, God, love and salvation in his struggle through the dark and gloomy forest which symbolizes conflict and temptations man may succumb to. The influence of Christianity and the Middle ages here shows his commitment to religion and faith. Moreover, his meeting of Virgil, who guides him to the mountain during his journey to salvation, reflects the positive impact of Virgil’s philosophy on Dante. The fourth part presents the Italian version of Canto 1 of the Inferno. The fifth section of my paper is the translation of Canto 1 of the Inferno from Italian to Arabic. Translating an excerpt of Dante’s masterpiece was not an easy task: I had to consult several critique texts besides the Italian source text with explanations, and also some English versions to overcome any translation difficulties. As a student of translation, my goal was to be faithful in relaying to the Arabic audience the authenticity of Dante’s work, his themes, passions and aesthetic style. Finally, I present a conclusion including a comment on the translation and the bibliography of the sources I have consulted.

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The LHCb experiment at the LHC, by exploiting the high production cross section for $c\overline{c}$ quark pairs, offers the possibility to investigate $\mathcal{CP}$ violation in the charm sector with a very high precision.\\ In this thesis a measurement of time-integrated \(\mathcal{CP}\) violation using $D^0\rightarrow~K^+K^-$ and $D^0\rightarrow \pi^+\pi^-$ decays at LHCb is presented. The measured quantity is the difference ($\Delta$) of \(\mathcal{CP}\) asymmetry ($\mathcal{A}_{\mathcal{CP}}$) between the decay rates of $D^0$ and $\overline{D}^0$ mesons into $K^+K^–$ and $\pi^+\pi^-$ pairs.\\ The analysis is performed on 2011 data, collected at \(\sqrt{s}=7\) TeV and corresponding to an integrated luminosity of 1 fb\(^{-1}\), and 2012 data, collected at \(\sqrt{s}=8\) TeV and corresponding to an integrated luminosity of 2 fb\(^{-1}\).\\ A complete study of systematic uncertainties is beyond the aim of this thesis. However the most important systematic of the previous analysis has been studied. We find that this systematic uncertainty was due to a statistical fluctuation and then we demonstrate that it is no longer necessary to take into account.\\ By combining the 2011 and 2012 results, the final statistical precision is 0.08\%. When this analysis will be completed and published, this will be the most precise single measurement in the search for $\mathcal{CP}$ violation in the charm sector.