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Marcel Duchamp precursore della curatela indipendente? Elementi per un'influenza duchampiana nella concezione dello spazio espositivo in Gene R. Swenson e Brian O'Doherty
Get PDFL'introduzione della tesi mette a confronto l'eredità dell'invezione del ready-made con l'affermarsi di happening e environment, attraverso il confronto con testi critici della prima metà degli anni Sessanta (per es. Susan Sontag).
Soggetto della prima parte della tesi sono le cinque mostre surrealiste a cui Marcel Duchamp ha collaborato, tra il 1938 e il 1961, in veste di organizzatore e allestitore. Si procede a riepilogare e analizzare i diversi punti di vista in cui questa collaborazione è stata descritta in ambito storico-artistico, con particolare attenzione alla letteratura critica su Duchamp. Particolare attenzione è data all'inclusione (o meno) delle mostre surrealiste nel corpus di opere dell'artista.
Le conclusioni critiche sulla impossibilità di giungere a una definizione di questa collaborazione (sia essa una definizione che la riconduca alla sfera artistica oppure ad una pre-curatoriale) vengono messe a confronto con i due case studies. Di Gene R. Swenson, critico principalmente legato alla Pop art, viene analizzata con particolare attenzione la posizione anti-formalista espressa dal progetto espositivo e critico "The Other Tradition", 1966. Di Brian O'Doherty sono stati studiati gli elementi di contiguità e prese di distanza dall'eredità duchampiana, rintracciabili tanto nella produzione artistica tanto in quella critica
Multimodal Distributional Semantics
No full textAlthough being one very simple statement, the distributional hypothesis - namely, words that occur in similar contexts are semantically similar - has been granted the role of main assumption in many computational linguistic techniques. This is mostly due to the fact that it allows to easily and automatically construct a representation of word meaning from a large textual input.
Among the computational linguistic techniques that are corpus-based and adopt the distributional hypothesis, Distributional semantic models (DSMs) have been shown to be a very effective method in many semantic-related tasks. DSMs approximate word meaning by vectors that keep track of the patterns of co-occurrence of words in the processed corpora. In addition, DSMs have been shown to be a very plausible computational model for human concept cognition, since they are able to simulate several psychological phenomena.
Despite their success, one of their strongest limitations is that they entirely represent word meaning in terms of connections with other words. Cognitive scientists have argued that, in this way, DSMs neglect that humans rely also on non-verbal experiences and have access to rich sources of perceptual knowledge when they learn the meaning of words.
In this work, the lack of perceptual grounding of distributional models is addressed by exploiting computer vision techniques that automatically identify discrete "visual words" in images, so that the distributional representation of a word can be extended to also encompass its co-occurrence with the visual words of images it is associated with.
A flexible architecture to integrate text- and image-based distributional information is introduced and tested on a set of empirical evaluations, showing that an integrated model is superior to a purely text-based approach, and it provides somewhat complementary semantic information with respect to the latter
The Ontogenesis of Counterfactual Emotions: Regret and Relief
No full textThe aim of the present work is to investigate the development of counterfactual emotions in children aged 3 to 10. More specifically, this work deals with the development of the emotions of regret and relief. Five studies were conducted to determine at which age children start to understand, to feel and to attribute to others counterfactual emotions, as well as to experience the comparison with others during a choice. Study 1 aims to replicate Weisberg and Beck’s paradigm, developed in 2010; and its results point out that children are able to feel regret at 5 years of age and relief at 7. Study 2 introduces some methodological changes and shows that children are able to report regret and relief starting at 6. The importance of the responsibility for the choice in the experience of regret is supported by the results concerning the manipulation of sense of agency (Study 3), with an effect on the experience of counterfactual emotions starting at 6 years old. To investigate the relationship between the ability to attribute to others emotions and to feel an emotion, study 4 aims to test whether children attribute to others regret and relief before experiencing them. The last study (Study 5: participants aged 3-11) concerns the development of social comparison and the experience of envy or gloating compared with the experience of regret and relief. The results reveal an effect of social comparison that precedes the effects of the two counterfactual emotions
The neuronal RNA binding protein HuB as a potential tumor suppressor in glioblastoma
No full textPost-transcriptional regulation is emerging as a fundamental step in gene expression that, when altered, can contribute to carcinogenesis. To identify potentially altered translational networks in glioblastoma multiforme (GBM), the worst of brain tumors, we correlated genomic alterations and mRNA levels of RNA-binding proteins (RBPs) in 372 publicly available GBM samples and identified 56 RBPs whose copy number alterations correlate with their altered expression levels in at least 15% of the samples. Among the genes identified using our parameters, HuB (ELAVL2) was deleted in 48% of the samples and down-regulated in more than 90% of these. Given the evidence for HuB activity as a differentiation factor in neuronal cells, we hypothesized that it may act as an oncosuppressor. However, ELAVL2 maps to the same chromosomal band (9p21.3) as CDKN2A, the most frequently inactivated oncosuppressor in gliomas, giving the possibility that ELAVL2 loss is simply a consequence to the CDKN2A deletion and therefore a passenger, albeit very frequent, mutation. To test this possibility, we analyzed the structure of the deletion spanning the two loci by qPCR analysis of 233 GBM samples, testing for the presence of the intervening region, and we obtained evidence that two independent focal deletions occurred in about 20% of the GBM samples bearing homo- and/or heterozygous deletion at CDKN2A and ELAVL2. This result highlights that, in rare but recurrent cases, ELAVL2 deletion occurs independently from CDKN2A deletion, supporting the hypothesis that loss of HuB activity is a condition contributing to tumor progression. This hypothesis was tested using U87MG cells, a commonly used glioma cell line homozygously deleted for CDKN2A and heterozygously deleted for ELAVL2 and primary glioma initiating cells (GICs) homozygously deleted for both genes. Migration, invasion and capacity to form nuerospheres were determined in U87MG cells upon HuB silencing and overexpression, and in GICs upon HuB expression. HuB expression in both cell models resulted in a decreased in migration, invasivity and the capacity to form neurospheres, supporting the hypothesis that HuB act as a tumor suppressor. We finally showed that HuB is able to determine an increase of p21 protein in normal murine neuroblast cells, providing a possible mechanism for HuB-mediated suppression of glioma cell clonality
Studies in Endogenous Macroeconomic Dynamics
No full textThis thesis focuses on endogenous approaches to studying macroeconomic dynamics and evaluates this tradition from different perspectives. It traces the origins and development of non-linear, endogenous theories of business cycles from its early beginnings up to its present frontiers. It argues that these theories emerged out of an attempt to reconcile the then existing corpus of (essentially static) economic theory with empirically observed fluctuations. It offers a re-reading of Harrod's `The Trade Cycle' and demonstrates that the accelerator in his theory to be non-linear and consequently claims that Harrod's text contains essential elements that constitute an endogenous theory.
On the mathematical front, it examines the role of existence and uniqueness theorems (in particular, the Poincare--Bendixson Theorem in planar endogenous models of economic dynamics. Their underpinnings, their use and influence on the mathematical models of aggregate macroeconomic fluctuations are critically evaluated. In this context, it considers Goodwin(1951)'s nonlinear model of business cycles and shows how existence and uniqueness of limit cycles can be established even for the case of an asymmetric, nonlinear, accelerator with only one nonlinearity. This is achieved using a result by de Figueiredo(1960). It argues that an excessive reliance on proving 'existence' and 'uniqueness' hampered the enlargement of scope of nonlinear, endogenous theories. It outlines the non-constructive aspects of these theorems and discusses the issue of computability for limit cycles in these planar models.
Furthermore, some methodological issues related to computational economic dynamics are analyzed. From an algorithmic point of view, it contends that there are inherent undecidabilities associated with many important properties of these dynamic models. These include characterizing attractors, determining their number, the domains of attraction and the possibility of exhibiting chaos, all of which have been important for dynamic economic theories. It makes a case for resorting to algorithmic economic dynamics in the future in order to overcome some of the limitations faced by the endogenous tradition
Security Testing of Web and Smartphone Applications
No full textWeb applications have become integral part of everyday life, as they are used by a huge number of customers on regular basis, for daily operations in business, leisure, government or academia, and so correctness of these applications is fundamental. In particular, security is a crucial concern especially for these applications that are constantly exposed to potentially malicious environments.
Cross-site scripting (XSS for short) is considered one of the major threats to the security of web applications. Missing input validation can be exploited by attackers to inject malicious code into the application under attack. Static analysis supports manual security review
in mitigating the impact of XSS-related issues, by suggesting a set of potential problems, expressed in terms of candidate vulnerabilities. A security problem spotted by static analysis, however, only consists of a list of (possibly complicated) conditions that should be satisfied
to concretely exploit a vulnerability. Static analysis does not provide examples of what input values must be used to make the application execute the sometimes complex execution path that causes a XSS vulnerability. Executable test cases, on the contrary, consist of a runnable and reproducible evidence of the vulnerability mechanics. Then, test cases represent a valuable support for developers who should concretely understand security problems in detail before fixing them.
The urge for reliable and secure web applications motivates the development of automatic, inexpensive, thus effective security testing methods, whose aim is to verify the presence of security-related defects. Security tests consist of two major parts, input values that need to be generated to run the application in the hope of exposing the vulnerabilities, and the decision if the obtained output
actually exposes the vulnerabilities, the latter is known as the “oracle”. However, current approaches to either generate security tests and to define security oracles have limitations.
To address the shortcomings of approaches for input value generation for security, this dissertation proposes a structured approach, inspired by software testing, based on the combination of genetic algorithms and concrete symbolic execution. This combined strategy is compared with genetic algorithms and with concrete symbolic execution in their atomic forms, in terms of coverage and efficiency on
four case study web applications, showing to be effective for security testing. In fact, genetic algorithms resulted to be able to generate input values only for few and simple vulnerabilities when not combined with other approaches. However, their contribution is fundamental to improve the coverage of those input values generated by concrete
symbolic execution.
The dissertation also explores the possibility to define oracle components that can be integrated with input generation strategies to perform security testing of web applications, so to expose security-related faults. A security oracle can be seen as a classifier able to detect when a vulnerability is exploited by a test case, i.e. verifying if a test case is an instance of a successful attack. This dissertation presents two distinct approaches to define security oracles, either (1) by applying tree kernel methods, and (2) by resorting to a model of
the application under analysis when run in harmless situations. In the former approach, the classifier is trained on a set of test cases containing both safe executions and successful attacks, in the aim of
learning important structural properties of web pages. In the latter, the learning phase is devoted to analyze web pages generated only in safe conditions, in order to build a “safe” model of their syntactic structure. Then, in the actual testing phase, both oracles are used
to classify new output pages either as “safe tests” or as “successful attacks”.
Furthermore, the dissertation moves few steps onto the world of applications for smartphone, in the attempt of breaking the barriers of our research and bringing the lesson learned from the experience in the domain of web applications towards a new domain. To motivate our work, we noticed that an important reason behind the popularity of
smartphones and tablets is the huge amount of available applications to download, to expand functionalities of the devices with brand new features. Official stores provide a plethora of applications developed by third parties, for entertainment and business, mostly for free.
Again, security represents a fundamental requirement: for example, confidential data (e.g., phone contacts, global GPS position, banking data and emails) might be disclosed by vulnerable applications and so, sensitive applications should carefully be tested to avoid security
problems. The dissertation proposes a novel approach to perform security testing with respect to the communication among applications on mobile devices with the objective of spotting errors in the routines that validate incoming messages
Statistical Relational Learning for Proteomics: Function, Interactions and Evolution
No full textIn recent years, the field of Statistical Relational Learning (SRL) [1, 2] has
produced new, powerful learning methods that are explicitly designed to solve
complex problems, such as collective classification, multi-task learning and
structured output prediction, which natively handle relational data, noise,
and partial information. Statistical-relational methods rely on some First-
Order Logic as a general, expressive formal language to encode both the data
instances and the relations or constraints between them. The latter encode
background knowledge on the problem domain, and are use to restrict or bias
the model search space according to the instructions of domain experts. The
new tools developed within SRL allow to revisit old computational biology
problems in a less ad hoc fashion, and to tackle novel, more complex ones.
Motivated by these developments, in this thesis we describe and discuss the
application of SRL to three important biological problems, highlighting the
advantages, discussing the trade-offs, and pointing out the open problems.
In particular, in Chapter 3 we show how to jointly improve the outputs
of multiple correlated predictors of protein features by means of a very gen-
eral probabilistic-logical consistency layer. The logical layer — based on
grounding-specific Markov Logic networks [3] — enforces a set of weighted
first-order rules encoding biologically motivated constraints between the pre-
dictions. The refiner then improves the raw predictions so that they least
violate the constraints. Contrary to canonical methods for the prediction
of protein features, which typically take predicted correlated features as in-
puts to improve the output post facto, our method can jointly refine all
predictions together, with potential gains in overall consistency. In order
to showcase our method, we integrate three stand-alone predictors of corre-
lated features, namely subcellular localization (Loctree[4]), disulfide bonding
state (Disulfind[5]), and metal bonding state (MetalDetector[6]), in a way
that takes into account the respective strengths and weaknesses. The ex-
perimental results show that the refiner can improve the performance of the
underlying predictors by removing rule violations. In addition, the proposed
method is fully general, and could in principle be applied to an array of
heterogeneous predictions without requiring any change to the underlying
software.
In Chapter 4 we consider the multi-level protein–protein interaction (PPI)
prediction problem. In general, PPIs can be seen as a hierarchical process
occurring at three related levels: proteins bind by means of specific domains,
which in turn form interfaces through patches of residues. Detailed knowl-
edge about which domains and residues are involved in a given interaction has
extensive applications to biology, including better understanding of the bind-
ing process and more efficient drug/enzyme design. We cast the prediction
problem in terms of multi-task learning, with one task per level (proteins,
domains and residues), and propose a machine learning method that collec-
tively infers the binding state of all object pairs, at all levels, concurrently.
Our method is based on Semantic Based Regularization (SBR) [7], a flexible
and theoretically sound SRL framework that employs First-Order Logic con-
straints to tie the learning tasks together. Contrarily to most current PPI
prediction methods, which neither identify which regions of a protein actu-
ally instantiate an interaction nor leverage the hierarchy of predictions, our
method resolves the prediction problem up to residue level, enforcing con-
sistent predictions between the hierarchy levels, and fruitfully exploits the
hierarchical nature of the problem. We present numerical results showing
that our method substantially outperforms the baseline in several experi-
mental settings, indicating that our multi-level formulation can indeed lead
to better predictions.
Finally, in Chapter 5 we consider the problem of predicting drug-resistant
protein mutations through a combination of Inductive Logic Programming [8,
9] and Statistical Relational Learning. In particular, we focus on viral pro-
teins: viruses are typically characterized by high mutation rates, which allow
them to quickly develop drug-resistant mutations. Mining relevant rules from
mutation data can be extremely useful to understand the virus adaptation
mechanism and to design drugs that effectively counter potentially resistant
mutants. We propose a simple approach for mutant prediction where the in-
put consists of mutation data with drug-resistance information, either as sets
of mutations conferring resistance to a certain drug, or as sets of mutants with
information on their susceptibility to the drug. The algorithm learns a set
of relational rules characterizing drug-resistance, and uses them to generate
a set of potentially resistant mutants. Learning a weighted combination of
rules allows to attach generated mutants with a resistance score as predicted
by the statistical relational model and select only the highest scoring ones.
Promising results were obtained in generating resistant mutations for both
nucleoside and non-nucleoside HIV reverse transcriptase inhibitors. The ap-
proach can be generalized quite easily to learning mutants characterized by
more complex rules correlating multiple mutations
Europa im Bild. Imaginationen Europas in Wochenschauen in Deutschland, Frankreich, Großbritannien und Österreich 1948-1959
No full textLe "immagini dell'Europa" di cui è fatta menzione nel titolo rappresentano costrutti mentali o luoghi comuni (topoi) connessi, appunto, all'idea di Europa e veicolati dai cinegiornali analizzati. Tali immagini possono essere considerate delle proposte di definizione di Europa, quali furono offerte al pubblico negli anni Cinquanta. Un tema che, considerata la discussione attuale sull'identità europea si rivela di notevole attualità. I cinegiornali offrono inoltre agli storici la possibilità unica e fino ad ora non sfruttata, di analizzare le fonti filmiche relative ai primi anni d'integrazione europea. Oggetto di indagine sono, in primo luogo, gli atti di fondazione dell'integrazione europea, come ad esempio la firma dei Trattati di Roma, i dibattiti parlamentari o la presentazione del Piano Schuman, ovvero atti politici di ordine simbolico e rituale. Le riprese dei cinegiornali tradussero tali conferenze e cerimonie di sottoscrizione dei contratti in fatti comunicati; nella prospettiva della ricerca storico-politica tali avvenimenti acquisirono significato proprio attraverso la loro comunicazione. Infine, uno degli obiettivi della presente ricerca è il confronto tra la politica "reale" e quella "simbolica"
Analisi economica del diritto penale negli Stati Uniti d'America
No full textIn questa tesi si sono voluti esaminare i pregi e gli inconvenienti che derivano dall’applicazione della teoria microeconomica neoclassica ad ambiti che travalicano quelli tradizionali, attinenti principalmente alle teorie della produzione e del consumo.
L’elaborato si propone di ricostruire la storia e gli sviluppi dell’analisi economica del diritto e la sua più recente applicazione al diritto penale.
Dopo aver analizzato le origini di tale fenomeno, l’attenzione si focalizza sulle problematiche attinenti al rapporto tra economia e diritto, un binomio che spesso fa emergere aspetti conflittuali e divergenti ma che, nel tempo, ha visto affievolirsi l’astio e la competizione e che potrebbe raggiungere, gradualmente e cautamente, un rapporto di collaborazione reciproca.
Si delinea, dunque, una panoramica degli apporti che l’economia sostiene di poter offrire al diritto in generale ed un’approfondita analisi di quella che viene definita l’essenza dell’analisi economica del diritto: la teoria della scelta razionale applicata al diritto penale.
Una volta descritte le maggiori teorie sull’applicazione dei principi economici nella costituzione, nell’implementazione e nel miglioramento di un ordinamento giuridico, vengono presentate le specifiche applicazioni dei criteri descritti ed elaborati dai principali autori al sistema penale e se ne evidenziano le potenzialità e le deficienze.
Alla luce delle ricerche svolte, è possibile affermare che l’analisi economica del diritto possa offrire al legislatore un fondamentale apporto: essa ricorda ed approfondisce i problema dell’allocazione delle risorse e della loro scarsità che non possono essere sottovalutati nell’amministrazione di un ordinamento giuridico.
Il nucleo centrale di tale tesi riguarda la concreta applicazione dei modelli e degli strumenti economici nell’analisi di alcune tra le più importanti ed eclatanti scelte legislative fatte negli Stati Uniti d’America.
Attraverso l’analisi dei dati e delle statistiche disponibili in tema di criminalità, è possibile, infatti, sottolineare i punti di forza e di debolezza delle strategie politico-criminali attuate per combattere i fenomeni della recidiva (si analizzano in tal senso il livello di efficienza della pena detentiva in generale e della cosiddetta legge dei “Tre Strikes”), della criminalità connessa allo spaccio di sostanze stupefacenti, dei reati violenti e le problematiche connesse alle norme sulla detenzione di armi da fuoco.
Nonostante la naturale ritrosia del giurista europeo, a seguito di tale analisi, si sono riscontrati risultati sorprendenti che, se prudentemente trattati, potrebbero dare degli utili spunti di riflessione per il miglioramento dell’attuale sistema giuridico penale
Le vitae medievali di Romedio
No full textRomedio e il dibattito storiografico: Il presente lavoro nasce dal desiderio di affrontare la questione romediana in un’ottica nuova, che unisca l’approfondimento della tradizione ad uno studio dei racconti agiografici di Romedio secondo un approccio culturale più vasto. Nello specifico, in una prima parte ci si propone di inquadrare la questione romediana attraverso il dibattito storiografico che nelle diverse epoche ha permesso di delineare come estremamente problematico e assolutamente non univoco il profilo dell’eremita anaune, a rischio di ideologizzazioni e strumentalizzazioni politiche della sua figura.
Le agiografie medievali di Romedio: Lo sviluppo della tesi parte dall’analisi della tradizione medievale delle leggende romediane. Dopo aver presentato ciascuna Vita, sia dal punto di vista dei manoscritti che delle edizioni a stampa, si riconosce quale obiettivo principale l’opportunità di approfondire lo studio dell’ultima agiografia dell’eremita anaune, denominata in questa sede come versione K, in virtù della scoperta che la leggenda romediana riportata dal manoscritto sangiorgiano della biblioteca di Karlsruhe (K = Karlsruhe, Badische Landesbibliothek, St. Georgen 14, ff. 1r -10r) ci consegna la più recente e la più interessante agiografia, frutto della contaminazione di due versioni precedenti, corrispondenti alle Vitae BHL 7144 e 7145.
L’edizione della vita K: L’allestimento dell’edizione della vita K verte attorno a due questioni fondamentali: si unisce infatti la problematica di un’agiografia attestata da un codex unicus allo studio del codice illustrato. Dopo aver riconosciuto la stretta corrispondenza che l’agiografia K intesse con le 10 illustrazioni che la accompagnano, si individua un rapporto biunivoco tra il testo e le immagini, tale però da superare, nelle suggestioni visuali introdotte, il contenuto veicolato dal solo testo scritto.
Le icone biografiche: Per questa ragione si è scelto di connettere lo studio storico –letterario delle leggende romediane al contributo di ulteriori discipline quali la paleografia, ma soprattutto agli studi iconografici e storico –artistici. Si è rilevato molto proficuo il confronto con la tradizione iconica di matrice orientale. Nello specifico si è proposta una connessione tra le illustrazioni del codice K e le tradizionali celebrazioni in occasioni delle feste dei santi: si è potuto stabilire un netto parallelismo tra l’esposizione delle icone biografiche dei santi durante la pubblica lettura delle loro agiografie, affinché il fedele, immerso nella contemplazione del ritratto venerabile, potesse trovare conferma e motivo di riflessione nella corrispondenza dei fatti narrati dall’agiografia con gli episodi più significativi rappresentati iconograficamente. Considerato quindi l’allestimento codicologico della Vita di Romedio riportata dal manoscritto di Karlsruhe, pare di assistere alla proposta, all’interno di un manoscritto illustrato, dell’usanza delle icone biografiche.
Suggestioni fantastiche e meravigliose: Terminato lo studio di K è parso opportuno un ulteriore raffronto con l’intera tradizione medievale delle leggende agiografiche romediane, dal quale è emerso come le suggestioni fantastiche e meravigliose appaiano come elemento prioritario. Le 5 agiografie propongono un ritratto di Romedio tracciato sulla base di nuclei narrativi comuni: il rapporto con Vigilio, il nascere della vocazione, la santità della vita eremitica, l’eccezionalità della sua esistenza. Pur nella specificità di ciascuna Vita, le 5 leggende romediane trovano così nell’elemento narrativo l’elemento unificante. Il gusto del narrare si riconosce infatti nella costante e crescente proposta di suggestioni fantastiche e meravigliose. Le peculiarità individuate all’interno della versione K apparivano infatti in nuce già nella versione più antica della Vita di Romedio, contenuta nel Liber epilogorum in gesta sanctorum di Bartolomeo da Trento, dove l’autore trecentesco dichiarava esplicitamente come l’intento di delectatio accompagnasse il proposito dell’edificatio fidelium. Partendo così dall’identificazione, secondo la classificazione di Le Goff, di scenari fantastici e corrispondenti al sentire medievale, le suggestioni meravigliose all’interno delle agiografie romediane individuano un motivo estremamente interessante e produttivo