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Dinamiche formative di due siti di riferimento del Paleolitico nella Penisola Iberica sud-orientale. Analisi micromorfologica dei depositi di Cueva Antón e Cueva Negra (Spagna, Murcia).
No full textIl presente lavoro consiste nello studio delle stratificazioni archeologiche di due siti del Paleolitico della Penisola Iberica di recente esplorazione, Cueva Antón e Cueva Negra del Estrecho del Río Quípar (Murcia, Spagna). Finalità della ricerca è di chiarire la genesi dei depositi e l’ambiente in cui è avvenuto la frequentazione umana. L’analisi delle stratificazioni di entrambi i siti si è avvalsa della descrizione e del rilievo eseguito sul terreno e dello studio microscopico del sedimento, in particolare dello studio micromorfologico di sezioni sottili.
L’accumulo della stratificazione pleistocenica di Cueva Antón, sito del Paleolitico Medio composto in prevalenza da sedimento alluvionale fine, è dovuto alla periodica tracimazione del fiume Mula e registra più cicli sedimentari ben riconoscibili che descrivono lo sviluppo diacronico della pianura alluvionale del fiume Mula. La presente ricerca illustra come il fiume Mula ai tempi della frequentazione dei gruppi del Paleolitico Medio avesse una configurazione a multicanale e un regime costante ad indicare delle precipitazioni piovose varia distribuite sull’intero anno e non concentrate stagionalmente come accade oggi in un clima tipicamente Mediterraneo. L’attività fluviale è documentata da depositi fluvio-palustri, di rotta/crevasse, di riempimento di canale abbandonato, di esondazioni fini a seguito di eventi di piena. Gli apporti autoctoni nella forma di breccia sono minoritari, ma assumono maggiore importanza nella parte superiore del deposito datata al MIS 3 dove derivano dall’azione discontinua del gelo. Il deterioramento climatico ambientale è indicato micromorfologicamente dalla presenza di pedorelitti provenienti dall’erosione del suolo tipo terra rossa che ricopriva i dintorni del sito a seguito della diminuzione della copertura forestale e di una microstruttura lenticolare e frammenti angolosi di roccia locale, entrambi prodotti dal gelo superficiale. La frequentazione antropica è attestata in una varietà di ambienti sedimentari in stretta relazione con lo scorrere del fiume, dalla pianura alluvionale prossimale ad una pianura alluvionale distale interessata nelle ultime fasi di frequentazione da crioclastismo e/o crioturbazione. La microstratigrafia dell’unità archeologica III-i/j individua un’unica fase di utilizzo dei focolari riconosciuti su campo, i quali, in parte, rappresentano superfici prodotte da una singola frequentazione. Le dinamiche fluviali sono responsabili dell’alterazione delle strutture di combustione determinando il dilavamento dei materiali combusti distribuendoli presso la superficie di occupazione; l’alterazione ha visto inoltre la compartecipazione dell’alterazione microbiale dei materiali organici-limosi. Le dinamiche sedimentarie di bassa energia, l’alterazione postdeposizionale di limitata entità principalmente connessa all’idromorfia temporanea dell’ambiente alluvionale, la conformazione stessa del riparo sottoroccia hanno garantito un’ottima conservazione del record sedimentario ed archeologico rendendo il sito di Cueva Antón un archivio ad alta risoluzione. La presente ricerca riconosce che il deposito di Cueva Negra, inquadrabile nel Paleolitico Inferiore e di cui non era stata studiata né le genesi né la stratigrafia, si compone di sedimento limo sabbioso laminato di natura alluvionale. La presenza di una superficie erosiva riempita da una lente di ghiaia permette di identificare due complessi geoarcheologici riferibili al Pleistocene: inferiormente si osserva un deposito con granulometria fine che culmina al tetto in un suolo incipiente, troncato dalla suddetta superficie, al di sopra della quale si trova un deposito laminato ed uno superiore con granulometria più sabbiosa. A livello micromorfologico il sedimento si compone di materiali provenienti dalle formazioni del Pliocene affioranti poco a monte del sito presso Rambla de Tarragoya e di materiali archeologici e biologici giacenti sulla superficie del riparo stesso in parte rielaborati dal mezzo idrico a cui si aggiunge una componente autoctona derivante dalla disgregazione della volta rocciosa. L’analisi micromorfologica evidenzia come la sequenza sedimentaria colorata rilevata alla base del deposito, da cui provengono frammenti di selce e di fauna/microfauna termoalterati ritenuti testimoniare la combustione antropica, si componga di sedimento laminato derivante da un accumulo alluvionale di bassa energia, di guano, in parte rielaborato ed alterato, di carbonato di calcio pedogenetico connesso allo sviluppo di microrganismi e radici in corrispondenza di una stabilizzazione superficiale. L’analisi micromorfologica indica che tale sequenza derivi dalla termoalterazione intenzionale in situ
La Bibbia nei primi trovatori
Get PDFLa tesi idaga la presenza di riferimenti biblici all'interno dei testi di due fra i più antichi, e importanti, poeti occitani: Guglielmo IX e Jaufre Rudel. Alcuni testi del primo – Ben vueill que sapchon li pluzor, Companho, tant ai agutz d’avols conres e Companho, farai un vers … covinen – hanno rivelato una tale densità di allusioni bibliche, utilizzate per lo più in chiave polemica e dissacrante, da richiedere analisi minuziose e approfondite. Nel caso di Jaufre Rudel la presenza di espressioni e temi biblici, o più generalmente religiosi, era già stata messa in luce da diversi interpreti; ma un più accurato esame del suo breve e compatto canzoniere ha portato a scoprire altri riferimenti, a correggerne alcuni già proposti, a proporre alla luce di queste indagini nuove interpretazioni di passi oscuri o controversi. I capitoli dedicati a questi due trovatori sono preceduti da un’introduzione nella quale è discusso un problema di grande rilevanza metodologica: quello che riguarda i testi, i canali e le mediazioni attraverso i quali era conosciuta la Bibbia nel medioevo, in particolare nel Sud della Francia
Il Mausoleo Martinengo nella Brescia del Rinascimento. Forma, storia e materiali
Get PDFLa tesi prende in esame il Mausoleo Martinengo un’opera scultorea in marmo e bronzo collocata a Brescia e realizzata tra il 1503 e il 1518. Lo studio esamina l’opera dal punto di vista materico e riguardo la fortuna critica. Sono proposti spunti di attribuzione e modelli architettonici di derivazione
Technologies for Supporting Social Participation with a focus on intergeneretional Interactions
No full textLoneliness increases mortality risk by 50% and is one of the main causes of depression. Several factors like living far away from the family, not being able to move much due to physical problems, or being unable to use communication technologies favor the likeliness of feeling lonely, especially in later life. We propose Lifehsare, a system for intergenerational communications that facilitates connecting people, enabling them to participate in the life of each other either in an active (synchronous interactions) or passive (asynchronous interactions) way. Current proposals for intergenerational communication do not address the problems related to the lack of time to share and lack of topic to talk that young usually have when interacting with their older relatives. Our proposal addresses these problems by implementing a method that requires no effort to share on the side of the young and by automatically enhancing the shared information. Furthermore, our experience with the evaluation of our proposal was translated into design recommendations that extend the current literature on design guidelines for applications for older adults
Expert Finding for Requirements Engineering
No full textRequirements Engineering (RE) revolves around requirements, from their discovery to their satisfaction, passing through their formalisation, modification, and traceability with other project artefacts, like preliminary interviews or resulting source codes. Although it is clear for many that involving knowledgeable people is an important aspect of many RE tasks, no proper focus has been given to Expert Finding (EF) systems, leading to have only few related works in the field. Our work attempts to fill this gap by investigating several dimensions of EF: conceptual by analysing the literature about expertise and its evaluation, formal by revising the usual representation of expert rankings, and practical by designing an EF system. As a result, we provide (i) a metamodel grounded in literature from Psychology to identify requirements for EF systems, (ii) a novel formalisation of experts rankings which solves limitations observed in usual EF measures, (iii) two variants of an EF system which builds on usual RE indicators (accessible knowledge and social recognition), and (iv) an enriched evaluation process which investigates deeper the consistency and correctness of an EF system
Il dio "ipoumano". Storia delle teologie degli atomisti antichi.
Get PDFIl lavoro compie una ricostruzione sistematica delle teologie degli atomisti antichi (Democrito, Epicuro, i tardi Epicurei), delineando le somiglianze e le differenze che esse intrattengono. La dissertazione si compone di cinque capitoli. I primi quattro ricostruiscono le teologie degli atomisti, mentre il quinto evidenzia le ricadute etiche delle stesse. L'idea principale che viene argomentata è che, pur nelle loro differenze a volte molto marcate, questi autori costituiscono una tradizione di pensiero unitaria, che propone che una divinità esista ma non sia provvidente, senza con ciò scadere in una posizione ateistica. Infatti, gli atomisti comunque rileggono in chiave dialettica il modo di intendere usuale della pietà religiosa, arrivando così ad esempio a rileggere in chiave innovativa l'uso della preghiera. Da richiesta di assistenza diretta dell'essere umano a Dio, questa diventa un modo per conoscere e percepire la natura divina
Contributions to Semantic Textual Similarity Algorithms
No full textSimilarity plays a central role in language understanding process. However, it is always difficult to precisely define on which type of data and what similarity metrics we can apply in order to assess the similarity of two texts.
According to this spirit, the task Semantic Textual Similarity (STS) was introduced as a pilot task at the Semantic Evaluation (SemEval) workshop in year 2012.
This thesis seeks to investigate the variances of performance of STS systems with respect to the heterogeneous data sources, and find solutions to alleviate these variances to improve the system performance. We carry a series of works focusing on addressing different aspects of measuring semantic similarity for texts under the umbrella of the Semantic Textual Similarity task. Firstly, we analyze the variance of system performance on dierent corpora with preliminary experiments and propose the hypothesis
that system performance depends heavily on the type of train and test corpora coming from heterogeneous sources. We analyze a standard textual similarity model built on vectorial representation and we derive a couple
of modalities which help significantly alleviating the negative in influence of vectorial mapping model. In particular, we study how structural information and the most advanced word alignment models in Machine Translation
improve the accuracy of systems. Our analysis also leads us to carry out, for the first time, an analysis between Semantic Relatedness and Textual Entailment, then we propose a co-learning model to improve the accuracy on both tasks by exploiting their mutual relationship.
As a result, all these steps lead to a consistent improvement over the standard model which is manifested across corpora. The evaluation shows that our system systematically achieves and goes beyond the former state of the art, whereas it also reduces the variation of the accuracy on various types of corpora
New states challenged: education, peacebuilding and statebuilding in post-conflict Kosovo and East Timor
No full textThe provision of education has been a core function legitimizing the modern nation-state. Behind education one finds the building of citizenship, between demands for social cohesion and national identification, as well as the preparation of the labour force for the national economy. The moulding of a working education system remains a key challenge for new states and states emerging from armed conflict. Qualitative and quantitative scholarly literature exploring the causal relationship between education and civil war leaves no doubt about the salience of education systems in conflict-affected states. While a vast body of studies exists on education and violent conflict, less attention has been devoted to the role of education in peacebuilding and statebuilding. Above all, little research has been conducted into how externally promoted efforts at rebuilding education systems may affect (or fail to affect) the consolidation of peace. This study focuses on the ways in which a variety of international actors shape national education systems in states that have emerged out of armed conflict, and how these systems reflect and affect peacebuilding and statebuilding. From these premises, I have conducted fieldwork in Kosovo and East Timor, two recent cases where major statebuilding and peacebuilding interventions have been launched. The research first has mapped education programming and reform by identifying the main actors that have been part of the process. Second, I have conceptualized the ‘how’ and ‘why’ of these reforms by analysing primary source documents and interviewing key local and international stakeholders. Finally, after identifying the emerging forms of education systems, I have critically analysed the ways in which externally assisted education have reflected and affected processes of building the state and consolidating peace. The research has found that post-war reconstruction in both cases has led to the emergence of externally-driven and hybrid education systems whereby priorities are set in the intersection between local and international actors, often lacking coordination. Presenting features of extra-territoriality and denationalization, such education systems are a combination of global education policies and contextual local agendas. Rather than bringing the education system out of fragility, international interventions have determined and perpetuated a condition of dependency on international assistance. Humanitarian and stability imperatives have determined educational choices and priorities and education has neither addressed nor transformed root causes of the conflicts, missing the opportunity to contribute to social cohesion, change and justice. Overall, education has been a marginal sector within the broader political economy of peacebuilding and statebuilding, and a mere reflection of the principles and practices that underpin them. Rather than impacting on such processes, interventions in education in Kosovo and East Timor have reflected, legitimised and enhanced the prevailing models of peacebuilding and statebuilding, and in doing so, have incorporated their dilemmas, pitfalls and shortcomings
READY, STEADY, AND GO. A Transcranial Magnetic Stimulation Study of Set-Related Inhibitory Activity in the Human Dorsal Precentral Region
No full textSuccessfully acting largely depends on moving at the right time. Consider a member of an orchestra just few instants before starting to play her piece. She should be ready not only to launch the planned movements when appropriate, but also to stop them if required. Action initiation and control are characteristic features of many of our daily life actions. There is a large amount of evidence in monkeys and humans suggesting that the dorsal premotor cortex (PMD) and the supplementary motor areas (SMA) might be critically involved in these features. However, the distinctive role of these areas is still matter of controversy. The aim of the present thesis is to provide some preliminary steps toward a comprehension of whether and how the human dorsal precentral areas may selectively contribute to action initiation and control. In doing this we shall introduce and discuss a series of transcranial magnetic stimulation (TMS) experiments carried out with two different paradigms, namely dual-coil TMS and single pulse TMS paradigm. These experiments were primarily devoted to explore the structural and functional properties of PMD. They also allowed us to assess whether PMD and SMA may be differentially and selectively involved in action control. In more detail, we first investigated the structural connectivity between PMD and the ipsilateral orofacial M1, introducing a novel dual-coil TMS approach. Results displayed the existence of short-latency influences of the left PMD on the ipsilateral orofacial M1, measured by recording motor evoked potentials (MEPs) in the orofacial muscles. Then, taking advantage of this novel approach, we started to explore the functional PMD-M1 connectivity. We tested the short-latency effects of TMS, as measured by changes in orofacial MEPs, during a delayed motor task. The results showed an inhibitory activity in the PMD-M1 module during the SET-period. We also manipulated the duration of the SET-period, to establish whether the effects were time-locked to the start of the delay period or rather time-locked to the predicted GO-signal. Hence, the investigation of the PMD-M1 connectivity paved us the way to explore, first, the role of PMD in initiating action and, then, the differential role of PMD and SMA in controlling and inhibiting action. Indeed, we run a further study, in which we carried out two single pulse TMS experiments. We first stimulated PMD during a stop-signal task, then we contrasted the PMD stimulation with SMA stimulation when participants underwent the same stop-signal task. There are five chapters to come. In Chapter 1 we shall review some key studies exploring anatomical and functional properties of PMD and SMA in both monkeys and humans, with particular emphasis on their putative role in action initiation and control. In Chapter 2 we shall focus on the methodological aspects of our experimental studies. In particular, we shall introduce the so-called twin- or dual-coil TMS paradigm, discuss its main approaches present in the literature and propose a variant of them. In Chapter 3 we shall present and discuss our first dual-coil TMS study exploring, for the first time, the ipsilateral PMD-corticofacial system connectivity. In Chapter 4 we shall examine three dual-coil TMS studies investigating the functional connectivity between PMD and ipsilateral M1 during a motor delayed task. Finally, in Chapter 5 we shall scrutinize two single pulse TMS studies capitalizing on a stop-signal task in order to assess the role of PMD and SMA in action control. Results and future lines of research will be sketched in the Concluding remarks
Inference with Distributional Semantic Models
No full textDistributional Semantic Models have emerged as a strong theoretical and practical approach to model the meaning of words. Indeed, an increasing body of work has proved their value in accounting for a wide range of semantic phenomena. Yet, it is still unclear how we can use the semantic information contained in these representations to support the natural inferences that we produce in our every day usage of natural language. In this thesis, I explore a selection of challenging relations that exemplify these inferential processes. To this end, on one hand, I present new publicly available datasets to allow for their empirical treatment. On the other, I introduce computational models that can account for these relations using distributional representations as their conceptual knowledge repository. The performance of these models demonstrate the feasibility of this approach while leaving room for improvement in future work