Contextual novelty changes reward representations in the striatum

Reward representation in ventral striatum is boosted by perceptual novelty, although the mechanism of this effect remains elusive. Animal studies indicate a functional loop (Lisman and Grace, 2005) that includes hippocampus, ventral striatum, and midbrain as being important in regulating salience attribution within the context of novel stimuli. According to this model, reward responses in ventral striatum or midbrain should be enhanced in the context of novelty even if reward and novelty constitute unrelated, independent events. Using fMRI, we show that trials with reward-predictive cues and subsequent outcomes elicit higher responses in the striatum if preceded by an unrelated novel picture, indicating that reward representation is enhanced in the context of novelty. Notably, this effect was observed solely when reward occurrence, and hence reward-related salience, was low. These findings support a view that contextual novelty enhances neural responses underlying reward representation in the striatum and concur with the effects of novelty processing as predicted by the model of Lisman and Grace (2005)

Resección del conducto auditivo vertical en un hurón con adenocarcinoma de glándulas ceruminosas

Un hurón con adenocarcinoma de glándulas ceruminosas, neoplasia pobremente descrita en esta especia, fue tratado mediante la técnica de resección del conducto auditivo vertical. Se describe la adaptación del procedimiento a este caso. El resultado fue satisfactorio, mostrando la viabilidad de esta técnica quirúrgica en hurones

Effects of maceration on the amino acid content of Chardonnay musts and wines

Chardonnay musts were macerated for 0, 6, 12, and 18 h and wines analyzed immediately after fermentation and at 6 months of bottle ageing. Maceration implies an increase of the amino acid content in the must immediately after fermentation and in the final wine. Wines from macerated musts have significantly higher levels of gamma-amino butiric acid, serine, glycine, histidine and alanine than wines from non-macerated musts. The content of these amino acids could help to examine whether there has been a maceration process or not. Must macerated for 6 h is characterized by higher contents of almost all amino acids. The only exceptions were glycine and glutamine. It is concluded that the optimum maceration time for Chardonnay must is 6 h when a maximum amino acid content is reached. After 6 months the amino acid concentrations in bottled wines were higher than in wines shortly after fermentation. Obviously the final equilibrium of amino acids had not been reached and during bottle ageing amino acids continued to be set free into the medium from yeast cells or their autolysis. During this time wines tend to reach a similar amino acid concentration independent of the maceration time of their respective musts

Fractura diafisaria del antebrazo : tratamiento por fijación externa. Bases mecánico-anatómicas

Intentamos explicar en este trabajo las bases teórico-prácticas que seguimos en las fracturas diafisarias del antebrazo en su tratamiento mediante fijación externa según nuestros conocimientos anatómico-mecánicos.We try to explain in ihis paper the theoreticpractical basis that we follow in the dyaphiseal fractures of the forearm by skeletal fixation treatment according to our mechanical and anatomical knowledge

¿Hacia la adquisición de competencias con actividades MBL?

La distribución a los centros de Cataluña de los equipamientos necesarios ha contribuido a un cierto desarrollo en la utilización de sistemas de captación de datos (MBL) en las aulas de secundaria. Los datos de los que se dispone sugieren que la utilización del equipamiento por parte del profesorado de secundaria es baja a pesar de haberse proporcionado ocasiones para la formación. Una de las posibles causas de esta situación puede ser la falta de reflexión sobre como deberían ser diseñadas las actividades con MBL para favorecer la adquisición de competencias científicas, así como cuál debería ser la gestión del aula para conseguir un aprendizaje más eficaz. En esta comunicación presentaremos los aspectos que, a partir de nuestra experiencia como formadoras y como participantes en el proyecto Comenius The effective use of ICT in science education, creemos tendrían que ser tenidos en cuenta a la hora de planificar actividades con MBL

Advertising non-premium products as if they were premium: The impact of advertising up on advertising elasticity and brand equity

Non-premium brands occasionally emulate their premium counterparts by using ads that emphasize premium characteristics such as superior performance and exclusivity. We define this practice as “advertising up” and develop hypotheses about its short- and long-term impact on advertising elasticity and brand equity respectively. We test the hypotheses in two large-scale empirical studies using a comprehensive dataset from the automotive industry that includes, among others, the content of 2317 television ads broadcast over a period of 45 months. The results indicate that advertising up increases (decreases) short-term advertising elasticity for non-premium products with a low (high) market share. The results also show that an intensive use of advertising up over time leads to long-term improvements (reductions) in brand equity for expensive (cheap) non-premium products. Furthermore, an inconsistent use of advertising up leads to reductions in brand equity. The results imply that managers of non-premium products with a low market share can use advertising up to increase advertising effectiveness in the short run. However, advertising up will only generate long-term improvements in brand equity for expensive non-premium products. Finally, to avoid long-term reductions in brand equity, advertising up should be consistently used over time

Strict upper and lower boundswith adaptive remeshing in limit state analysis

By writing the limit state analysis as an optimisation problem, and after resorting to suitable discretisations of the stress and velocity field, we compute strict bounds of the load factor. The optimisation problem is posed as a Second Order Conic Program (SOCP), which can be solved very efficiently using specific algorithms for conic programming. Eventually, the optimum stress and velocity fields of the lower and upper bound problem are used to construct an error measure (elemental gap) employed in an adaptive remeshing strategy. This technique is combined with an additional adaptive nodal remeshing that is able to reproduce fan-type mesh patterns around points with discontinuous surface loads. We paticularise the resulting formulation for twodimensional problems in plane strain, with VonMises andMohr-Coulomb plasticity. We demonstrate the effetiveness of the method with a set of numerical examples extracted from the literature

Bounds and adaptivity for 3D limit analysis

In the present paper we compute upper and lower bounds for limit analysis in two and three dimensions. From the solution of the discretised upper and lower bound problems, and from the optimum displacement rate and stress fields, we compute an error estimate defined at the body elements and at their boundaries, which are applied in an adaptive remeshing strategy. In order to reduce the computational cost in 3D limit analysis, the tightness of the upper bound is relaxed and its computation avoided. Instead, the results of the lower bound are used to estimate elemental and edge errors. The theory has been implemented for Von Mises materials, and applied to two- and three-dimensions examples.Peer Reviewe

PaaS-IaaS Inter-Layer Adaptation in an Energy-Aware Cloud Environment

Cloud computing providers resort to a variety of techniques to improve energy consumption at each level of the cloud computing stack. Most of these techniques consider resource-level energy optimization at IaaS layer. This paper argues energy gains can be obtained by creating a cooperation between the PaaS layer (in charge of hosting the application/service) and the IaaS layer (in charge of handling the computing resources). It presents a novel method based on steering information and decision taking to trigger the PaaS and IaaS layers to adapt their energy mode in service operation, therefore enabling the Cloud stack to actively adapt to changing situations. Experimental results demonstrate such adaptation achieves dynamic energy management in each of the PaaS and IaaS cloud layers