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Impatto dei nuclei galattici attivi sul gas molecolare: una prospettiva radiativa e cinetica
Get PDFThe molecular phase of the interstellar medium (ISM) is crucial for star formation (SF) and galaxy evolution, undergoing significant changes due to feedback processes from SF and active galactic nuclei (AGNs). Newly formed stars and AGNs emit high-energy radiation, creating photodissociation regions (PDRs) and X-ray dominated regions (XDRs) in the ISM, influencing its heating/cooling rates and chemistry. They also induce turbulence and molecular outflows, crucial for galaxy evolution. This thesis examines the impact of AGNs on molecular gas from radiative and kinematic perspectives, using observational and theoretical approaches. Carbon monoxide (CO) emission, its spectral line energy distribution (SLED), and spatially resolved kinematics are used to trace excitation conditions. A study on the relative contribution of SF and AGN in a new sample of local active galaxies is presented, along with a physically motivated model for estimating CO excitation and line emission in active galaxies. Finally, a detailed kinematical analysis is provided for the multiphase ISM in the nearby Seyfert NGC 5506. This thesis demonstrates that AGNs influence both the excitation and kinematics of molecular gas, primarily in central regions, potentially constraining SF efficiency and contributing to its quenching.La fase molecolare del mezzo interstellare (ISM) è essenziale per la formazione stellare (SF) e l'evoluzione galattica. Subisce cambiamenti significativi a causa dei processi di feedback da SF e nuclei galattici attivi (AGN). Le stelle di nuova formazione e gli AGN emettono radiazioni ad alta energia, creando regioni di fotodissociazione (PDRs) e regioni dominate dai raggi X (XDRs) nell'ISM, influenzandone i tassi di riscaldamento/raffreddamento e la chimica. Inoltre, inducono turbolenza e flussi molecolari, fondamentali per l'evoluzione galattica. Questa tesi analizza l'impatto degli AGN sul gas molecolare da prospettive radiative e cinematiche, utilizzando osservazioni e approcci teorici. Per tracciare le condizioni di eccitazione, si utilizza l'emissione di monossido di carbonio (CO), il suo spettro di distribuzione energetica delle righe (SLED) e la sua cinematica risolta spazialmente. Si studia il contributo relativo di SF e AGN in un nuovo campione di galassie attive locali, e si presenta un modello fisicamente motivato per stimare l'eccitazione del CO e la sua emissione in riga nelle galassie attive. Infine, si fornisce un'analisi cinematica dettagliata dell'ISM multifase nella Seyfert locale NGC 5506. Questa tesi dimostra che gli AGN influenzano sia l'eccitazione che la cinematica del gas molecolare, soprattutto nelle regioni centrali, e che questo può limitare l'efficienza della SF, contribuendo al suo spegnimento
Adorno and the aesthetic. Genesis and development of a theoretical problem
Get PDFLa presente ricerca intende indagare la categoria dell’estetico nel pensiero di Theodor W. Adorno, mettendone in luce una dimensione che eccede il mero orizzonte artistico. Stando al titolo del suo incompiuto, lo sforzo filosofico adorniano si configurerebbe infatti come il tentativo di dar vita a una teoria che si qualifica come estetica, ossia che procede esteticamente. In tal senso, l’estetico assumerebbe una valenza teoretica che non trova alcuna tematizzazione testualmente esplicita, ma che, al contrario, sarebbe da rintracciare nel modo in cui una teoria estetica opera. Di conseguenza, l’estetico non si tradurrebbe affatto in un irrazionale rifiuto del medium concettuale, quanto piuttosto in una sua modalità d’applicazione che differisce significativamente da quella della teoria tradizionale. Estetica è precipuamente quella logica, altra dalla logica totalizzante, che affonda le proprie radici in quel terreno esperienziale e materiale che sfugge costitutivamente al concetto, pur alimentandolo. Riconoscere un’istanza teoreticamente performativa dell’estetico significa, allora, saper cogliere nel tematismo della teoria estetica quel tessuto denso di nessi tanto logicamente stringente, quanto refrattario a ogni identificazione integrale e, pertanto, sempre aperto al possibile e al non-identico.This research intends to investigate the category of the aesthetic in the thought of Theodor W. Adorno, highlighting its dimension that goes beyond the mere artistic horizon.
According to the title of his unfinished work, Adorno’s philosophical effort can indeed be seen as an attempt to give shape to a theory that qualifies itself as aesthetic, that is, that proceeds aesthetically. In this sense, the aesthetic would take on a theoretical value that is not textually explicit, but detected in the way an aesthetic theory operates. Thereby, the aesthetic does not coincide with an irrational rejection of the conceptual medium, but rather with a mode of its application that differs significantly from that of traditional theory. Aesthetic is primarily that logic, other than a totalising logic, which is rooted in the experiential and material ground that constitutively eludes the concept, while nourishing it. Recognising a theoretically performative instance of the aesthetic means, then, being able to grasp in the thematism of aesthetic theory that dense thread of connections, which is as logically stringent as it is refractory to any all-encompassing identification and, therefore, always open to the possible and the non-identical
Prostate cancer: evaluation of outcomes and prognostic factors in adjuvant and salvage radiation treatment
Get PDFAdjuvant radiotherapy in prostate cancer: impact of older age and hypofractionated regimens on acute and late toxicity. A multicenter comprehensive analysis
Background: The objective of this study was to assess the impact of patient and treatment characteristics on toxicity in prostate cancer patients receiving adjuvant radiotherapy (RT).
Materials and methods: This observational study evaluated both acute and late toxicity. Patient- (age; Charlson’s comorbidity index) and treatment-related characteristics (nodal irradiation; previous TURP; use, type, and duration of ADT, RT fractionation and technique, image-guidance systems, EQD2 delivered to prostate bed and pelvic nodes) were recorded and analyzed.
Results: A total of 381 patients were enrolled. The median EQD2 to the prostate bed was 71.4 Gy. 75.4% of patients were treated with intensity-modulated radiation therapy (IMRT) or volumetric-modulated arc therapy (VMAT). Acute G3 gastrointestinal (GI) and genitourinary (GU) toxicity rates were 0.5% and 1.3%, respectively. No patients experienced >G3 acute toxicity. The multivariable analysis of acute toxicity showed a statistically significant association between older age (> 65) and decreased odds of G≥2 GI acute toxicity (OR: 0.569; 95%CI: 0.329-0.973; p: 0.040) and decreased odds of G≥2 GU acute toxicity (OR: 0.956; 95%CI: 0.918- 0.996; p: 0.031). The 5-year late toxicity-free survival rates for G≥3 GI and GU toxicity were 98.1% and 94.5%, respectively. The only significant correlation found (Cox’s regression model) was a reduced risk of late GI toxicity in patients undergoing hypofractionation (HR: 0.38; 95% CI: 0.18-0.78; p: 0.008).
Conclusions: The unexpected results of this analysis could be explained by a “response shift bias” concerning the protective effect of older age and by treatment in later periods (using IMRT/VMAT) concerning the favorable effect of hypofractionation. However, the study suggests that age should not be a reason to avoid adjuvant RT and that the latter is well-tolerated even with moderately hypofractionated regimens
The free parliamentary mandate, intra-group discipline, and forms of protection of the individual member of Parliament
Get PDFIl principio del divieto di mandato imperativo affonda le sue radici in tempi ormai lontani, ma ha sempre dimostrato di avere una grande duttilità, cambiando forma a seconda dei mutamenti che hanno riguardato le condizioni sociali, politiche e istituzionali degli ordinamenti costituzionali. Tutt’oggi, infatti, si afferma come elemento strutturale del sistema di rappresentanza politica, nonostante i connotati di quest’ultimo siano profondamente diversi rispetto a quelli che esistevano quando è stata concepita la Costituzione repubblicana. L’obiettivo di questa ricerca dottorale è di evidenziare, dunque, il rinnovato significato di questa garanzia alla luce dell’attuale complessità del sistema di rappresentanza politica, che si compone di una sequenza di attori e di comportamenti differenti, ma connessi, che, distribuiti nell’arco di distinte fasi, formano un insieme complesso e composito. A tal fine, il lavoro si struttura in quattro capitoli e si sviluppa su due linee di indagine diverse, ma collegate tra loro da un rapporto di dipendenza. La prima linea di ricerca attiene al più generale tema del divieto di mandato imperativo, e come esso si colloca nel rapporto che esiste tra singolo rappresentante e gruppo parlamentare di appartenenza. La seconda linea di indagine, invece, si concentra sul tema delle forme di tutela del singolo rappresentante, alla luce della considerazione preliminare che il divieto di mandato imperativo debba essere garantito anche all’interno delle dinamiche parlamentari. Ciascun capitolo rappresenta un tassello necessario a elaborare la tesi conclusiva per cui la ridefinizione del rapporto tra gruppo e singolo dovrebbe realizzarsi necessariamente all’interno del gruppo stesso, attraverso canali di espressione del dissenso, ovvero attraverso l’attuazione del “metodo democratico” anche nell’organizzazione e nel funzionamento della formazione politica. È proprio all’interno di tale spazio, infatti, che, nell’odierno complesso sistema di rappresentanza, devono trovare una prima sintesi gli interessi veicolati anche dai singoli rappresentanti nello svolgimento del loro mandato parlamentare.Despite its long-lasting origins, the principle of the free parliamentary mandate has always proved to have great pliability, as it has changed shape and consistency according to the transformations that have affected the social, political, and institutional conditions of constitutional legal orders. Even today, the principle asserts itself as a structural element of the system of political representation, despite the latter’s connotations are very different from the ones that existed when the Italian republican Constitution was conceived. The aim of this doctoral research is, therefore, to highlight the renewed meaning of this guarantee in light of the current complexity of the system of political representation, which is construed on the basis of a sequence of different but connected actors and behaviors which are distributed over distinct phases, and which form a composite whole. With this aim in mind, the thesis is structured in four chapters and is developed along two different but related lines of inquiry. The first one concerns the more general topic of the prohibition of the imperative mandate, and how it fits into the relationship between the individual representative and its parliamentary group; whereas the second line of inquiry focuses on the issue of the forms of protection that can assist the individual representative. Each chapter is a necessary building block that leads up to the final thesis according to which the redefinition of the relationship between the political group and the individual member of Parliament should necessarily take place within the group itself, through proper channels of expression of dissent, and through the implementation of the “democratic method” in the group’s organization and functioning. Indeed, in today’s complex system of representation, the interests that are conveyed by individual representatives as they exercise their mandate should be synthesized especially in this particular political space
Leopardi, Pascal and Galilei in Giuseppe Raimondi's work
No full textIn questo lavoro si analizza la presenza e la funzione di Leopardi, Pascal, Galileo e alcuni scienziati del Seicento nell’opera di Giuseppe Raimondi attraverso lo studio della sezione bibliografica e di quella manoscritta del suo Fondo archivistico conservato presso la Biblioteca Umanistica “Ezio Raimondi”, Sezione di Filologia classica e Italianistica dell’Università di Bologna. Innanzitutto si analizza il percorso apparentemente contraddittorio di Raimondi, che negli stessi anni si indirizzò sia verso le Avanguardie francesi che verso il classicismo del “ritorno all’ordine” italiano. Attraverso lo studio del ruolo assunto da Leopardi durante il suo apprendistato letterario si cerca di approfondire il carattere di questo particolare bifrontismo. In secondo luogo si prendono in considerazione gli studi compiuti da Raimondi intorno a Pascal, indagando i segni di attenzione presenti sui volumi di e sul filosofo conservati nel Fondo, i quaderni manoscritti e le opere edite. Infine, viene proposta una ricostruzione dei momenti che portarono Raimondi a interessarsi della prosa scientifica del Seicento e si cerca di individuare i risultati di queste letture sull’elaborazione del suo ideale stilistico. La ricerca tenta dunque di fornire un profilo dello scrittore ricavato, oltre che dai testi, anche dal suo laboratorio teorico e creativo, mettendo in luce, al di là dell’influenza rondista, i modi in cui Raimondi affrontò un tema centrale della sua esperienza di scrittore, quello del rapporto tra realismo e immaginazione.In this thesis, the presence and function of Leopardi, Pascal, Galileo and some scientists of the seventeenth century in the work of Giuseppe Raimondi are analyzed through the study of the bibliographic and manuscript sections of his archival collection preserved at the Humanistic Library "Ezio Raimondi", Section of Classical Philology and Italian Studies of the University of Bologna. First of all, Raimondi's apparently contradictory path is analyzed: in the same years he was interested both in the French Avant-gardes and the classicism of the Italian "ritorno all'ordine". Through the study of the role assumed by Leopardi during his literary apprenticeship, an attempt is made to deepen the understanding of this ambivalence. Secondly, Raimondi's studies about Pascal are considered, investigating the author's annotations in the volumes of and about the philosopher preserved in the Collection, the handwritten notebooks and the published works. Finally, a reconstruction of the moments that led Raimondi to be interested in seventeenth-century scientific prose is proposed in order to identify the results of these readings on the elaboration of his stylistic ideal. The research therefore endeavor to provide a profile of the writer derived, as well as from the texts, also from his theoretical and creative laboratory, highlighting, beyond the influence of classicism, the ways in which Raimondi addressed a central theme of his writer's experience: the relationship between realism and imagination
From farm to school: investigating the potential of school food environments to transform the food system
No full textSustainable transformations of the food system are today at the heart of the global debate. To comply with the widely agreed need for change, a large scientific interest has been dedicated to the potential of school food environments for transforming food production and consumption trajectories. Besides being responsible for the nutritional quality of children’s diets, school meals also shape behaviours of the next generation consumers. Given that the relationships between the dietary patterns, consumption habits of children, the canteen setting, and the selection of food products for school consumption are complex and multifactorial, enlarging the body of analyses is essential for understanding patterns on how food is served and consumed. To this scope, this thesis adopts multiple approaches to understand sustainability dynamics behind school food environments and offers science-based implications derived from rigorous and reproducible social-science research. In particular, three studies are conducted: 1) a systematic literature review to explore the role of short food supply chains in supporting advancements towards global sustainability goalsin view of sustainable public procurement practices in schools 2) an evaluation study with a randomized control trial design to assess if inverting the sequence of dishes served in school canteens is an effective intervention for reducing food waste in primary school 3) an indicator-based assessment tool to measure the sustainability of school food environments integrating nutritional, environmental and social
implications via an easy-to-understand scoring system. Results of this thesis provide food professionals and policymakers with quantitative insights on areas of improvement of the sustainability status of school food environments. On this basis, effective tailor-made strategies can be designed in schools to foster food system transformations and tackle the fundamental goals of the 2030 Agenda for Sustainable Development
Dynamical modelling of early-type galaxies: analytical multi-component systems, and application to spherical gas accretion
Get PDFDynamical models, even when simplified, are of great importance, because they can be used, for example, to understand the dynamics of more complicated (i.e., realistic) models, as well as to obtain first indications about sensible choices of parameters to be subsequently refined with more time-consuming numerical methods. In this Thesis we present the construction of galaxy models simple enough to provide some insight into the main structural and dynamical properties of real galaxies. The work focuses on axisymmetric Jeans modelling for galaxies, assumed to be stationary collisionless stellar systems.
In particular, we consider ellipsoidal galaxies characterized by weakly flattened shape: this allows for the application of a technique, known as homoeoidal expansion, representing the theoretical framework underlying the entire modelling procedure. We apply this technique to two families of two-component galaxy models, solving the two-integral Jeans equations also in presence of a central black hole. The expansion method is then reviewed, analyzing and applying its two different interpretations to the case of simple one-component models: here the effectiveness of the homoeoidal approximation is examined using both analytical and numerical techniques; this method is finally adopted for the phenomenological interpretation of a real globular cluster.
A part of the Thesis is devoted to the study of the polytropic accretion of gas onto the black hole at the centre of spherical galaxies, modelled as the spherical limit of one of the two families of axisymmetric models previously discussed. In order to study the motion of gas flows we generalize the classical Bondi problem by taking into account the effects of the gravitational field of the host galaxy, and the radiation pressure due to electron scattering. We also elucidate some important thermodynamical properties of accretion, determining the underlying cooling/heating function leading to the phenomenological value of the polytropic index
Searching for fossil fragments into the galactic bulge
Get PDFThe exact mechanism that drove the formation of the bulge in the Milky Way and in analogous galaxies is still largely debated. Two main formation channels are currently invoked to reproduce the observed chemo-dynamical properties of the MW inner region: a dynamical secular evolution of the disk, and the merging at high redshift of massive clumps formedfrom the fragmentation of the primordial gas-rich disk. The global picture emerging from the photometric and spectroscopic analyses presented in this Thesis is that two peculiar Bulge stellar clusters, Terzan 5 and Liller 1, at odds with their appearance, did not undergo the same formation and evolution path of globular clusters (GCs). Conversely, they experienced a prolonged, multi-episode star formation history fueled by iron-enriched gas that had been deposited in the central region of the clusters. This is more likely explainable by invoking a self-enrichment process. These evidences make them strong candidate present-day remnants of the massive clumps observed in high-redshift galaxies, opening a new line of investigation: these peculiar stellar systems could represent the first observational proof of the hierarchical assembling process predicted by the clump-origin scenario, shedding new light on the formation of our bulge and galaxies’ bulges in a more general cosmological picture
Integrative metagenomics: compositional analysis, network based methods and computational pipeline development
Get PDFThis PhD thesis delves into the utilization and analysis of metagenomic data, employing next-generation sequencing (NGS) technologies to unravel microbial biodiversity and functions across diverse ecosystems. Central to the research is network analysis, revealing intricate relationships within microbial communities. Addressing challenges of compositional data and spurious correlations, the study develops theoretical methodologies, explores spurious correlations through simulations, and applies these approaches to various environmental contexts. Methodologically, the thesis focuses on minimizing spurious correlations in network construction, employing Aitchison's theory and the centered log-ratio transformation. Synthetic data generation models are developed to mimic real data characteristics. Case studies on wastewater and gut bacterial ecology showcase the effectiveness of tailored network methodologies, offering insights into temporal patterns and community dynamics. Computationally, the research harnesses High-Performance Computing (HPC) infrastructures, utilizing tools like Snakemake and Conda for efficient workflow management. In summary, the thesis advances metagenomics by elucidating microbial community interactions, tackling methodological hurdles, and introducing innovative computational approaches to unravel microbial ecology intricacies
The origins of american institutionalism: institutions, order, and conflict in the political and social thought of Thorstein B. Veblen and John R. Commons (1880-1918)
Get PDFLa ricerca ricostruisce come dentro le scienze socioeconomiche statunitensi a cavallo tra Ottocento e Novecento le istituzioni sociali e politiche vengono ripensate nella loro connessione con le categorie di ordine e di stabilità, di persistenza, di permanenza. Attingendo a una serie di fonti diverse vengono individuati i tratti comuni di una prospettiva storico-istituzionalista che tra i due secoli si definisce come paradigma forte dentro quasi tutti gli ambiti disciplinari in via di specializzazione. La ricostruzione si sofferma in particolare sulla riflessione di Thorstein B. Veblen e John R. Commons, considerati i due fondatori della «old institutional economics». La tesi storicizza le letture dei due autori per comprendere come, a ridosso di diverse congiunture, viene pensato e ripensato il valore politico dell’istituzione, come risposta alle urgenze di governo di una società in movimento, frammentata e conflittuale. Lette congiuntamente, le due letture perimetrano un ambito intellettuale e di riflessione dentro il quale Commons e Veblen esplorano costantemente visioni alternative dell’ordine: da un lato, l’immagine di un ordine istituzionale inteso come ordito che riflette ed esprime i caratteri, le linee di frattura e la forza auto-normativa del sociale; dall’altra, l’immagine di un ordine istituzionale che opera come limite e stabilizzatore, con l’obiettivo di contenere una conflittualità e un caos esponenziali dentro lo spazio sociale ed economico. La ricerca ricostruisce la definizione di un vocabolario dell’istituzione in primo luogo a fronte del dirompente conflitto animato dal repubblicanesimo diffuso e altamente politicizzato del movimento dei lavoratori degli ultimi decenni del XIX secolo; indaga la sua rimodulazione a partire dalla momentanea convergenza di diversi settori sociali intorno agli obiettivi di arbitrato e conciliazione dell’inizio del Novecento; infine, ne osserva le torsioni a ridosso del conflitto industriale negli anni che vanno dal 1906 alla Prima Guerra Mondiale.The research investigates how, within American socio-economic sciences at the turn of the 19th and 20th centuries, social and political institutions were reconsidered in their connection with the categories of order and stability, persistence, and permanence. The dissertation particularly focuses on the political and social thought of Thorstein B. Veblen and John R. Commons, considered the founders of the "old institutional economics." The thesis historicizes the interpretations of these two authors to understand how, in the face of various conjunctures, the political value of the institution was conceived and reconceived as a response to the governance urgencies of a society in motion, fragmented, and conflictual. Read together, these interpretations delineate a complex intellectual terrain within which Commons and Veblen consistently explored alternative visions of order: on one hand, the image of an institutional order seen as a fabric reflecting and expressing the characters and the self-regulating forces of society; on the other, the image of an institutional order that acts as a limit and stabilizer, aiming to contain the exponential conflict and chaos within the social and economic space. The research reconstructs the definition of an institutional vocabulary primarily in response to the disruptive conflict animated by the widespread and highly politicized republicanism of the labor movement in the last decades of the 19th century; then, it investigates its reformulation beginning with the temporary convergence of various social sectors around the goals of arbitration and conciliation at the start of the 20th century; finally, it observes its twists in the face of industrial conflict from 1906 to World War I