105,824 research outputs found
Iustitia generalis nel secolo XIII. Apporti alla tradizione etica medievale
No full textL'articolo analizza le distinzioni tra i possibili significati di "iustitia" in testi precedenti la traduzione dell'Etica nicomachea ad opera di Roberto Grossatesta e in opere di poco posteriori. Intende mostrare che la ricezione del pensiero aristotelico in questo ambito è stata influenzata da una pre-comprensione del problema forgiatasi nelle discussioni anteriori alla traduzione. In questo modo, l'incontro tra la teoria aristotelica della giustizia e la tradizione precedente si configura come un complesso gioco di influenze reciproche.
G. d'Onofrio è il curatore del volume
Effect of seasonality on the dynamics of an imitation-based vaccination model with public intervention
No full textWe extend here the game-theoretic investigation made by d'Onofrio et al (2012) on the interplay between private vaccination choices and actions of the public health system (PHS) to favor vaccine propensity in SIR-type diseases. We focus here on three important features. First, we consider a SEIR-type disease. Second, we focus on the role of seasonal fluctuations of the transmission rate. Third, by a simple population-biology approach we derive -with a didactic aim -the game theoretic equation ruling the dynamics of vaccine propensity, without employing 'economy-related' concepts such as the payoff. By means of analytical and analytical-approximate methods, we investigate the global stability of the of disease-free equilibria. We show that in the general case the stability critically depends on the 'shape' of the periodically varying transmission rate. In other words, the knowledge of the average transmission rate (ATR) is not enough to make inferences on the stability of the elimination equilibria, due to the presence of the class of latent subjects. In particular, we obtain that the amplitude of the oscillations favors the possible elimination of the disease by the action of the PHS, through a threshold condition. Indeed, for a given average value of the transmission rate, in absence of oscillations as well as for moderate oscillations, there is no disease elimination. On the contrary, if the amplitude exceeds a threshold value, the elimination of the disease is induced. We heuristically explain this apparently paradoxical phenomenon as a beneficial effect of the phase when the transmission rate is under its average value: the reduction of transmission rate (for example during holidays) under its annual average over-compensates its increase during periods of intense contacts. We also investigate the conditions for the persistence of the disease. Numerical simulations support the theoretical predictions. Finally, we briefly investigate the qualitative behavior of the non-autonomous system for SIR-type disease, by showing that the stability of the elimination equilibria are, in such a case, determined by the ATR
Service design lab : esperienze di ricerca didattica del service design per la sostenibilità e l'inclusione sociale : ediz. italiana e inglese
No full textNel contesto socio-economico contemporaneo, segnato da sfide ecologiche e disuguaglianze sociali, il Service Design assume un ruolo centrale nello sviluppo di soluzioni orientate all’inclusione sociale e sostenibilità ambientale. Attraverso metodi partecipativi, approcci sistemici e multidisciplinari, definisce relazioni e processi volti a migliorare l’esperienza dell’utente e generare valore per le organizzazioni coinvolte. Il volume esplora le basi teoriche, le metodologie partecipative e gli strumenti del Service Design, attraverso una lettura critica dei risultati progettuali ottenuti dalle attività di ricerca didattica svolte nel Laboratorio di Service Design, parte del corso di laurea magistrale in Eco Inclusive Design del Dipartimento di Architettura dell'Università G. d'Annunzio di Chieti-Pescara
Deterministic Control of SDEs with Stochastic Drift and Multiplicative Noise: A Variational Approach
No full textWe consider a linear stochastic differential equation with stochastic drift and multi-plicative noise. We study the problem of approximating its solution with the process that solves the equation where the possibly stochastic drift is replaced by a determinis-tic function. To do this, we use a combination of deterministic Pontryagin's maximum principle approach and direct methods of calculus of variations. We find necessary and sufficient conditions for a function u ? L-1(0, T) to be a minimizer of a certain cost functional. To overcome the problem of the existence of such minimizer, we also consider suitable families of penalized coercive cost functionals. Finally, we consider the important example of the quadratic cost functional, showing that the expected value of the drift component is not always the best choice in the mean squared error approximation
The beautiful monument: the aristocracy of images in Athenian funerary sculpture (c. 530–480 BCE)
No full textThe discoveries that have occurred over the last sixty years, together with chronological considerations and the appropriate evaluation of the epigraphic corpus, testify overall to the duration of the system of monumental funerary dedications well beyond the advent of democracy by Kleisthenes (508/7 BCE) and probably up to the end of the Persian Wars. This ‘longue durée’ will require the revision of the interpretation that mechanically links Archaic funerary monuments and the ruling “aristocracy” during pre-democratic political regimes in turn paving the way for a more detailed analysis of patronage. The monument is built according to precise rules of a visual rhetoric, aimed at enhancing its beauty, to match and reflect the excellence of the recipients – largely male and including impressive monuments for non-Athenians (xenoi) – and to define their social position through the joint devices of word and image. The evidence is discussed in detail, and the Author accepts the proposal that the grave statue of Aristodikos, one of the latest examples of the kouros type, wore a helmet. The head of a youth, found in the Kerameikos and likewise once equipped with a helmet, might attest to the next “step”: a grave statue in ponderation. The monuments recovered from Piraeus Gate are discussed, as well as Jeffery’s so-called Samian plot. A political interpreation of the bases with athletic scenes is proposed, connected with Sparta and the Athenian pro-Lacedemonian party (sphairomachia) or with Eretria and eastern Attica (the chariot scenes with hoplites), alluding to the Amarysia or to the Attic version of the event. Concluding, funerary monuments reflect the changes in Athenian society, which in turn are largely influenced by the international situation
Transcatheter valve-in-valve implantation for degenerated aortic bioprostheses: Still not ready for prime-time
No full textThe progressively increasing experience with transcatheter aortic valve implantation (TAVI) together with the publication of new prospective randomized studies showing the non-inferiority and sometimes the superiority of this technique when compared to surgical aortic valve replacement (SAVR) also in low risk patients [1,2] has led to the expansion of the indications for TAVI. Consequently, there has also been a growing interest towards transcatheter bioprostheses implantation in the setting of structural deterioration of previously implanted aortic xenografts in order to avoid surgical reintervention. Valve-in-valve (ViV) procedure represents a micro-invasive approach [3] for patients with degenerated aortic bioprostheses since it enables to implant a new valve inside the malfunctioning one, on the beating heart, with no need for cardiopulmonary bypass, with no skin incision and with local anesthesia if performed through a transfemoral access. All these aspects make ViV particularly interesting as an alternative therapeutic option in patients with failing bioprostheses. In this issue of the IJC, Dr. Woitek and his colleagues from Leipzig, evaluate their results with conventional redo surgery (Re-SAVR) and with valve-invalve transfemoral TAVI (VinV-TFAVI) in 258 consecutive patients [4]. As authors have correctly pointed out, this study should not be considered a true comparison of these techniques since baseline characteristics are different in the two cohorts, but rather a “hypothesi
- …
