Natalia López

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In this paper we introduce a new Stochastic Process Algebra: NMSPA. This new language presents the usual features of stochastic models but probability distributions are not restricted to be exponential. This fact increases the expressive power of the language in several ways. For example, we can specify actions that can be executed with probability 1 in a(More)
In order to describe probabilistic processes by means of a formal model, some considerations have to be taken into account. In this paper we present some of the ideas appeared in the literature that could help to define appropriate formal frameworks for the specification of probabilistic processes. First, we will explain the different interpretations of the(More)
In this paper we introduce WHAT, an intelligent tutor for learning the functional programming language Haskell. WHAT adapts its behavior not only individually for each student but also by considering the performance of similar students. The core of its adaptive part is based on the classification of students into classes (groups of students sharing some(More)
A sample of 2,086 university students in Valladolid (Spain) were surveyed in 1994 to assess their current use of illicit drugs. That information was used as a baseline to show the trends in the last decade in order to compare two other studies carried out on a similar target population in 1984 and 1990. Of those surveyed, 28.3% had taken some illicit drug(More)
Bisimulations are a broadly used formalism to deene the semantics of process algebras. In particular, by means of weak bisimulation most of the internal activity of processes may be abstracted. Unfortunately, this is not fully accomplished: for instance, the internal choice operator becomes non-associative since bisimulation can see the branching structure(More)
Little is known about how social media are used in cancer care. We conducted a systematic review of the use and taxonomy of social media in cancer-related studies, in PubMed, Web of Knowledge, CINAHL, and Google Scholar. We located 1350 articles published through October 2013; 69 met study inclusion criteria. Early research (1996-2007) was predominantly(More)
Cerebral palsy (CP) is a catastrophic acquired disease, occurring during development of the fetal or infant brain. It mainly affects the motor control centres of the developing brain, but can also affect cognitive functions, and is usually accompanied by a cohort of symptoms including lack of communication, epilepsy, and alterations in behavior. Most(More)
Many different types of auctions can be applied to determine selling prices, each of them fulfilling different properties. Among them, Vickrey auctions are specially interesting due to the fact that they disallow strategic behaviors of the bidders. In fact, the dominant strategy for each bidder consists in bidding his reserve price. However, somebody has to(More)
BACKGROUND To investigate the contribution of multidrug resistance 1 (MDR1) gene pharmacogenetics (G2677T/A and C3435T) to the efficacy of azathioprine in inducing remission in patients with Crohn's disease (CD). METHODS A cohort of 327 unrelated Spanish patients with CD recruited from a single center was studied. All patients were rigorously followed up(More)