Performance of Surgical Risk Scores to Predict Mortality after Transcatheter Aortic Valve Implantation

AbstractBackground:Predicting mortality in patients undergoing transcatheter aortic valve implantation (TAVI) remains a challenge.Objectives:To evaluate the performance of 5 risk scores for cardiac surgery in predicting the 30-day mortality among patients of the Brazilian Registry of TAVI.Methods:The Brazilian Multicenter Registry prospectively enrolled 418 patients undergoing TAVI in 18 centers between 2008 and 2013. The 30-day mortality risk was calculated using the following surgical scores: the logistic EuroSCORE I (ESI), EuroSCORE II (ESII), Society of Thoracic Surgeons (STS) score, Ambler score (AS) and Guaragna score (GS). The performance of the risk scores was evaluated in terms of their calibration (Hosmer–Lemeshow test) and discrimination [area under the receiver–operating characteristic curve (AUC)].Results:The mean age was 81.5 ± 7.7 years. The CoreValve (Medtronic) was used in 86.1% of the cohort, and the transfemoral approach was used in 96.2%. The observed 30-day mortality was 9.1%. The 30-day mortality predicted by the scores was as follows: ESI, 20.2 ± 13.8%; ESII, 6.5 ± 13.8%; STS score, 14.7 ± 4.4%; AS, 7.0 ± 3.8%; GS, 17.3 ± 10.8%. Using AUC, none of the tested scores could accurately predict the 30-day mortality. AUC for the scores was as follows: 0.58 [95% confidence interval (CI): 0.49 to 0.68, p = 0.09] for ESI; 0.54 (95% CI: 0.44 to 0.64, p = 0.42) for ESII; 0.57 (95% CI: 0.47 to 0.67, p = 0.16) for AS; 0.48 (95% IC: 0.38 to 0.57, p = 0.68) for STS score; and 0.52 (95% CI: 0.42 to 0.62, p = 0.64) for GS. The Hosmer–Lemeshow test indicated acceptable calibration for all scores (p > 0.05).Conclusions:In this real world Brazilian registry, the surgical risk scores were inaccurate in predicting mortality after TAVI. Risk models specifically developed for TAVI are required.

Energy policies for rural electrification: a social multi-criteria evaluation approach

In this article, a real-world case- study is presented with two general objectives: to give a clear and simple illustrative example of application of social multi-criteria evaluation (SMCE) in the field of rural renewable energy policies, and to help in understanding to what extent and under which circumstances solar energy is suitable for electrifying isolated farmhouses. In this sense, this study might offer public decision- makers some insight on the conditions that favour the diffusion of renewable energy, in order to help them to design more effective energy policies for rural communities.

Quality control and conduct of genome-wide association meta-analyses.

Rigorous organization and quality control (QC) are necessary to facilitate successful genome-wide association meta-analyses (GWAMAs) of statistics aggregated across multiple genome-wide association studies. This protocol provides guidelines for (i) organizational aspects of GWAMAs, and for (ii) QC at the study file level, the meta-level across studies and the meta-analysis output level. Real-world examples highlight issues experienced and solutions developed by the GIANT Consortium that has conducted meta-analyses including data from 125 studies comprising more than 330,000 individuals. We provide a general protocol for conducting GWAMAs and carrying out QC to minimize errors and to guarantee maximum use of the data. We also include details for the use of a powerful and flexible software package called EasyQC. Precise timings will be greatly influenced by consortium size. For consortia of comparable size to the GIANT Consortium, this protocol takes a minimum of about 10 months to complete.

Extensió de l'entorn SMARD per permetre la depuració d'aplicacions basades en agents mòbils

Un dels principals obstacles per l’adopció dels agents mòbils, fins i tot per tasques per les quals s’ha demostrat la seva idoneïtat, és la dificultat de desenvolupar-los. Aquest projecte aporta solucions per ajudar en aquest procés. Més concretament, per provar agents i observar-ne el seu comportament en un entorn de simulació, abans d’executar-los en un escenari real. Hem afegit un depurador i un constructor d’agents mòbils a la interfície gràfica de disseny d’itineraris de l’entorn SMARD. Fent servir afegit aquests nous components, el programador pot dissenyar, construir i fer proves d’un agent mòbil des d’aquesta aplicació.

Creation of a carrier-grade telco based on a voice over IP backbone

En aquesta memòria l'autor, fent servir un enfoc modern, redissenya i implementa la plataforma que una empresa de telecomunicacions del segle 21 necessita per poder donar serveis de telefonia i comunicacions als seus usuaris i clients. Al llarg d'aquesta exposició es condueix al lector des d'una fase inicial de disseny fins a la implementació i posada en producció del sistema final desenvolupat, centrant-nos en solucionar les necessitats actuals que això implica. Aquesta memòria cubreix el software, hardware i els processos de negoci associats al repte de fer realitat aquest objectiu, i presenta al lector les múltiples tecnologies emprades per aconseguir-ho, fent emfàsi en la convergència actual de xarxes cap al concepte de xarxes IP i basant-se en aquesta tendència i utilitzant aquesta tecnologia de veu sobre IP per donar forma a la plataforma que finalment, de forma pràctica, es posa en producció.

Competing with Asking Prices

In many markets, sellers advertise their good with an asking price. This is a price at which the seller will take his good off the market and trade immediately, though it is understood that a buyer can submit an offer below the asking price and that this offer may be accepted if the seller receives no better offers. Despite their prevalence in a variety of real world markets, asking prices have received little attention in the academic literature. We construct an environment with a few simple, realistic ingredients and demonstrate that using an asking price is optimal: it is the pricing mechanism that maximizes sellers’ revenues and it implements the efficient outcome in equilibrium. We provide a complete characterization of this equilibrium and use it to explore the positive implications of this pricing mechanism for transaction prices and allocations.

Competing with Asking Prices

In many markets, sellers advertise their good with an asking price. This is a price at which the seller will take his good off the market and trade immediately, though it is understood that a buyer can submit an offer below the asking price and that this offer may be accepted if the seller receives no better offers. Despite their prevalence in a variety of real world markets, asking prices have received little attention in the academic literature. We construct an environment with a few simple, realistic ingredients and demonstrate that using an asking price is optimal: it is the pricing mechanism that maximizes sellers' revenues and it implements the efficient outcome in equilibrium. We provide a complete characterization of this equilibrium and use it to explore the implications of this pricing mechanism for transaction prices and allocations.

Binding under Conflict Conditions: State-Space Analysis of Multivariate EEG Synchronization.

Real-world objects are often endowed with features that violate Gestalt principles. In our experiment, we examined the neural correlates of binding under conflict conditions in terms of the binding-by-synchronization hypothesis. We presented an ambiguous stimulus ("diamond illusion") to 12 observers. The display consisted of four oblique gratings drifting within circular apertures. Its interpretation fluctuates between bound ("diamond") and unbound (component gratings) percepts. To model a situation in which Gestalt-driven analysis contradicts the perceptually explicit bound interpretation, we modified the original diamond (OD) stimulus by speeding up one grating. Using OD and modified diamond (MD) stimuli, we managed to dissociate the neural correlates of Gestalt-related (OD vs. MD) and perception-related (bound vs. unbound) factors. Their interaction was expected to reveal the neural networks synchronized specifically in the conflict situation. The synchronization topography of EEG was analyzed with the multivariate S-estimator technique. We found that good Gestalt (OD vs. MD) was associated with a higher posterior synchronization in the beta-gamma band. The effect of perception manifested itself as reciprocal modulations over the posterior and anterior regions (theta/beta-gamma bands). Specifically, higher posterior and lower anterior synchronization supported the bound percept, and the opposite was true for the unbound percept. The interaction showed that binding under challenging perceptual conditions is sustained by enhanced parietal synchronization. We argue that this distributed pattern of synchronization relates to the processes of multistage integration ranging from early grouping operations in the visual areas to maintaining representations in the frontal networks of sensory memory.

The Role of supply constraints in multiplier analysis

Multiplier analysis based upon the information contained in Leontief's inverse is undoubtedly part of the core of the input-output methodology and numerous applications an extensions have been developed that exploit its informational content. Nonetheless there are some implicit theoretical assumptions whose implications have perhaps not been fully assessed. This is the case of the 'excess capacity' assumption. Because of this assumption resources are available as needed to adjust production to new equilibrium states. In real world applications, however, new resources are scarce and costly. Supply constraints kick in and hence resource allocation needs to take them into account to really assess the effect of government policies. Using a closed general equilibrium model that incorporates supply constraints, we perform some simple numerical exercises and proceed to derive a 'constrained' multiplier matrix that can be compared with the standard 'unrestricted' multiplier matrix. Results show that the effectiveness of expenditure policies hinges critically on whether or not supply constraints are considered.

Sistema integral d’anàlisi i avaluació d’un format general d’assignatura específic dels estudis de les arts

En el període 2006-2008, l'equip investigador de l'Observatori sobre la Didàctica de les Arts (ODAS) s'ha concentrat en la innovació i la investigació en el camp de la didàctica aplicada als estudis universitaris de les arts. Des del punt de vista propi de la investigació-acció, la finalitat ha estat la de plantejar i explorar una revisió integral de l'organització del treball a peu d'aula que fos extensible a d'altres assignatures i matèries. Així, prenent com a eix l'aprenentatge dels estudiants, les accions escomeses es fonamentaren en sis premisses: integració —de sessions de treball i activitats d'aprenentatge—, diversitat —d'escenaris, recursos i materials didàctics—, equilibri —entre coneixements i habilitats específiques i transversals—, modularitat —de les parts constitutives de la innovació proposada—, aplicabilitat —a d'altres assignatures i matèries— i progressió en la seva posada en marxa. I sobre aquestes bases, hom va establir cinc línies de treball: l'organització del treball a l'aula i del treball guiat de l'estudiant en diferents tipus de sessions, l'organització del treball autònom de l'alumne des dels pressupòsits d'una avaluació continuada, la incorporació de les TIC com autèntics recursos d'ensenyament-aprenentatge, la col·laboració amb d'altres unitats de la Universitat de Barcelona que tinguessin entre els seus objectius l'impuls de l'aprenentatge, i el seguiment del procés d'implantació de la iniciativa didàctica i l'anàlisi regular dels seus resultats. Pel que fa a aquest darrer punt, en aquest primer període, hom ha prioritzat l'estudi de les dades quantitatives i quasi-quantitatives derivades del judici dels alumnes que participaren en la nova proposta didàctica. En conseqüència, la investigació va acomplir una primera funció diagnòstica de la innovació docent duta a terme, i es va enquadrar en la categoria dels estudis descriptius transversals a través d'enquestes amb mostres probabilístiques.

The de facto independence of regulatory agencies and its consequences for policy making and regulatory outcomes

This dissertation focuses on the practice of regulatory governance, throughout the study of the functioning of formally independent regulatory agencies (IRAs), with special attention to their de facto independence. The research goals are grounded on a "neo-positivist" (or "reconstructed positivist") position (Hawkesworth 1992; Radaelli 2000b; Sabatier 2000). This perspective starts from the ontological assumption that even if subjective perceptions are constitutive elements of political phenomena, a real world exists beyond any social construction and can, however imperfectly, become the object of scientific inquiry. Epistemologically, it follows that hypothetical-deductive theories with explanatory aims can be tested by employing a proper methodology and set of analytical techniques. It is thus possible to make scientific inferences and general conclusions to a certain extent, according to a Bayesian conception of knowledge, in order to update the prior scientific beliefs in the truth of the related hypotheses (Howson 1998), while acknowledging the fact that the conditions of truth are at least partially subjective and historically determined (Foucault 1988; Kuhn 1970). At the same time, a sceptical position is adopted towards the supposed disjunction between facts and values and the possibility of discovering abstract universal laws in social science. It has been observed that the current version of capitalism corresponds to the golden age of regulation, and that since the 1980s no government activity in OECD countries has grown faster than regulatory functions (Jacobs 1999). Following an apparent paradox, the ongoing dynamics of liberalisation, privatisation, decartelisation, internationalisation, and regional integration hardly led to the crumbling of the state, but instead promoted a wave of regulatory growth in the face of new risks and new opportunities (Vogel 1996). Accordingly, a new order of regulatory capitalism is rising, implying a new division of labour between state and society and entailing the expansion and intensification of regulation (Levi-Faur 2005). The previous order, relying on public ownership and public intervention and/or on sectoral self-regulation by private actors, is being replaced by a more formalised, expert-based, open, and independently regulated model of governance. Independent regulation agencies (IRAs), that is, formally independent administrative agencies with regulatory powers that benefit from public authority delegated from political decision makers, represent the main institutional feature of regulatory governance (Gilardi 2008). IRAs constitute a relatively new technology of regulation in western Europe, at least for certain domains, but they are increasingly widespread across countries and sectors. For instance, independent regulators have been set up for regulating very diverse issues, such as general competition, banking and finance, telecommunications, civil aviation, railway services, food safety, the pharmaceutical industry, electricity, environmental protection, and personal data privacy. Two attributes of IRAs deserve a special mention. On the one hand, they are formally separated from democratic institutions and elected politicians, thus raising normative and empirical concerns about their accountability and legitimacy. On the other hand, some hard questions about their role as political actors are still unaddressed, though, together with regulatory competencies, IRAs often accumulate executive, (quasi-)legislative, and adjudicatory functions, as well as about their performance.

Development of allocentric spatial memory abilities in children from 18 months to 5 years of age.

Episodic memories for autobiographical events that happen in unique spatiotemporal contexts are central to defining who we are. Yet, before 2 years of age, children are unable to form or store episodic memories for recall later in life, a phenomenon known as infantile amnesia. Here, we studied the development of allocentric spatial memory, a fundamental component of episodic memory, in two versions of a real-world memory task requiring 18 month- to 5-year-old children to search for rewards hidden beneath cups distributed in an open-field arena. Whereas children 25-42-months-old were not capable of discriminating three reward locations among 18 possible locations in absence of local cues marking these locations, children older than 43 months found the reward locations reliably. These results support previous findings suggesting that allocentric spatial memory, if present, is only rudimentary in children under 3.5 years of age. However, when tested with only one reward location among four possible locations, children 25-39-months-old found the reward reliably in absence of local cues, whereas 18-23-month-olds did not. Our findings thus show that the ability to form a basic allocentric representation of the environment is present by 2 years of age, and its emergence coincides temporally with the offset of infantile amnesia. However, the ability of children to distinguish and remember closely related spatial locations improves from 2 to 3.5 years of age, a developmental period marked by persistent deficits in long-term episodic memory known as childhood amnesia. These findings support the hypothesis that the differential maturation of distinct hippocampal circuits contributes to the emergence of specific memory processes during early childhood.

Creació d'un entorn web de treball per a una biblioteca : Fent ús de Struts, Tiles i Hibernate

El següent projecte final de carrera vol assolir assolir la creació d'un entorn web de treball per a una Biblioteca. L'aplicació al món real es base en un mòdul administratiu, que podrà ser utilitzat pels treballadors de la pròpia Biblioteca i un mòdul que servirà de consulta als socis.

Bases de dades multimedia

La part del treball de recerca inclou un estudi que recull l'evolució de les bases de dades des del seu començament fins a l'actualitat, incloent-hi una previsió del futur de les bases de dades; finalment, com a aprofundiment, s'hi estudien les bases de dades multimèdia. D'altra banda, la part pràctica mira d'aplicar tots el coneixements adquirits durant l'estudi de recerca i durant les diferents assignatures de la carrera, i intenta obtenir una aplicació que es pugui fer servir en el món real.

Compression-based Image Registration

Image registration is an important component of image analysis used to align two or more images. In this paper, we present a new framework for image registration based on compression. The basic idea underlying our approach is the conjecture that two images are correctly registered when we can maximally compress one image given the information in the other. The contribution of this paper is twofold. First, we show that the image registration process can be dealt with from the perspective of a compression problem. Second, we demonstrate that the similarity metric, introduced by Li et al., performs well in image registration. Two different versions of the similarity metric have been used: the Kolmogorov version, computed using standard real-world compressors, and the Shannon version, calculated from an estimation of the entropy rate of the images