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Theory of fluctuations in disordered systems
No full textThe thesis is devoted to the study of various aspects of disordered and glassy systems.
In the first part of the thesis, we have studied the problem of charachterizing the critical dynamical fluctuations of structural glasses at the dynamical transition point. A field theory approach has been developed combined with the replica method and it has been introduced an effective theory that is capable to describe the dynamical heterogeneities at the dynamical transition point. A Ginzburg criterion has been derived to understand the region of validity of the mean field approach.
These results are valid for the critical behavior of the dynamics in the beta regime.
To understand what happens in the alpha regime we have developed a Boltzmann Pseudodynamics approach to structural glasses that is able to cupture the quasi-equilibrium nature of the glassy dynamics in the long time regime.
The third part of the thesis is devoted to the study of the glass and jamming physics of hard spheres in the infinite dimension limit.
In this context we show that this model displays a Gardner transition that affects deeply the jamming part of the phase diagram. This means that to describe correctly the jamming properties of hard spheres we need to take into account the full replica symmetry breaking effects. The full replica symmetry breaking formalism for hard sphere systems is completely developed.
The last part of the thesis is devoted to study mode coupling dynamics around a quasi-continuous transition
Synthesis of IR-analogue of cyclopamine and enzymatic enantioselective synthesis of (S)-norcoclaurine
No full textThe huge biosynthetic potential of plants as a renewable source of fine chemicals and pharmaceuticals has long been recognized. Identification of biologically active compounds from plants and improvement of the isolation methods are of great interest for their therapeutic applications. Moreover, they are a huge source of inspiration for the design of new active compounds, not only for their structure, carrying the features responsible for drug’s biological activity, but also for the biosynthetic pathways that Nature has established for them, often a suggestion for an easier synthetic access to the targeted molecule. Therefore, the future demands for pharmaceuticals is dependent on a detailed understanding of the biologically active compounds, of their biosynthetic pathways as well as the complex mechanisms regulating the development of diseases. Thus in both sections of this work two biologically active compounds and their therapeutic properties are discussed in relation to their methods of synthesis.
The first part of this work deals with the synthesis of a potential inhibitor of the hedgehog signaling pathway, a key regulator of multiple developmental processes of embryogenesis as well as in adult tissue maintenance and repair. Since its aberrant activation has been linked to the development of severe malignancies, the hedgehog signaling inhibitors has emerged as a valuable tool for cancer treatment. Several modulators have been reported so far, including cyclopamine, the first known inhibitor identified in 1968. Since its discovery, only in 2009 the first synthetic route to cyclopamine was established by Giannis et al. using a biomimetic and diastereoselective approach. This flexible synthetic strategy provides access to several structural modifications leading to multiple potential analogues of cyclopamine that do not exist in nature. Exploiting this route, in order to have new insights into the biological activity of the natural compound, the first synthetic analogue of cyclopamine was designed and partially synthesized.
In the second part of this work the catalytic activity of (S)-norcoclaurine synthase was investigated and used to set up a method for an easy access to (S)-norcoclaurine, the first common intermediate of all benzylisoquinoline alkaloids. Recently (S)-norcoclaurine gained a widespread interest in both organic and medicinal chemistry for its well recognized rich pharmacological potential in the treatment of several diseases. So far, several synthetic strategies have been employed based on asymmetric catalytic approaches involving the use of a chiral metal catalyst. Even though these synthetic routes are highly efficient and guarantee a very good enantioselectivity, they entail extensive use of organic solvents and metal catalysts. In order to develop a clean and green synthetic process towards (S)-norcoclaurine without using organic solvents and metal catalysts, an efficient one pot-two steps synthesis was set up, starting from tyrosine and dopamine in the presence of (S)-norcoclaurine synthase providing the first attempt to exploit the potential of a “Pictet-Spengler” enzyme in the direct synthesis of chiral benzylisoquinolines
Specie e taxa critici del genere Romulea Maratti:indagini morfologiche e biosistematiche
No full textWe report some data concerning distribution, macro- / micromorphology and molecular biology of italian species belonging to Romulea Maratti genus, in order to present a contribution to the current systematic view which appears redundant, confused and misleading at specific and subspecific level
ANTONIO VALERI: ARCHITETTO DELL'ARCADIA NELLA FABBRICA DI SAN PIETRO (1648-1736)
No full textStudio monografico relativo alla vita ed alle opere di Antonio Valeri, personalità di rilievo nel panorama del Sei-Settecento romano, esponente dell'architettura dell'Arcadia
Donatori e istituzioni: antropologia del sistema sangue in Toscana
No full textIl lavoro descrive il sistema sangue toscano prendendo in considerazione tre differenti livelli: il sistema sanitario, l'indistria privata e soprattutto le associazioni di volontariato, AVIS toscana
Il paradosso del cliché
No full textLa mia ricerca sul Paradosso del cliché – il titolo non a caso fa eco al ben più noto Paradoxe sur le comedien – si è posta come oggetto di indagine le pratiche di codificazione del gesto nella tradizione del teatro occidentale. Queste pratiche sono spesso associate ad una negazione dell’atto creativo dell’attore, poiché prevedono l’uso di forme codificate o cliché . D’altra parte le strategie di codificazione hanno, in epoche diverse, implicato delle riflessioni sullo statuto dell’attore, sulle sue potenzialità e sulla sua efficacia. Nel Paradosso del cliché quello che preme far emergere è che esiste una strategia di lavoro comune che comporta l’uso di tecniche di codificazione a livelli diversi del processo compositivo
L'ESENZIONE DALL'IMPOSTA COMUNALE SUGLI IMMOBILI (I.C.I.) APPARTENENTI AD ENTI ECCLESIASTICI DESTINATI AD ATTIVITÀ DI RELIGIONE E DI CULTO SEPPUR SVOLTE IN FORMA COMMERCIALE
No full textTesi dottorale in materia di diritto canonico ed ecclesiastico con riferimento agli aspetti fiscali e tributari degli enti ecclesiastici
