University admission marks in Catalonia: Some highlights from the empirical research

The results of the examinations taken by graduated high school students who want to enrol at a Catalan university are here studied. To do so, the authors address several issues related to the equity of the system: reliability of grading, difficulty and discrimination power of the exams. The general emphasis is put upon the concurrent research and empirical evidence about the properties of the examination items and scores. After a discussion about the limitations of the exams' format and appropriateness of the instruments used in the study, the article concludes with some suggestions to improve such examinations.Admissions process, reliability of grading, index of difficulty, discrimination power

On the classification of Togliatti systems

In [MeMR], Mezzetti and Mir\'{o}-Roig proved that the minimal number of generators μ(I) of a minimal (smooth) monomial Togliatti system I⊂k[x0,¿,xn] satisfies 2n+1≤μ(I)≤(n+d−1n−1) and they classify all smooth minimal monomial Togliatti systems I⊂k[x0,¿,xn] with 2n+1≤μ(I)≤2n+2. In this paper, we address the first open case. We classify all smooth monomial Togliatti systems I⊂k[x0,¿,xn] of forms of degree d≥4 with μ(I)=2n+3 and n≥2 and all monomial Togliatti systems I⊂k[x0,x1,x2] of forms of degree d≥6 with μ(I)=7

VLBI observations of SN2011dh: imaging of the youngest radio supernova

We report on the VLBI detection of supernova SN2011dh at 22GHz using a subset of the EVN array. The observations took place 14 days after the discovery of the supernova, thus resulting in a VLBI image of the youngest radio-loud supernova ever. We provide revised coordinates for the supernova with milli-arcsecond precision, linked to the ICRF. The recovered flux density is a factor 2 below the EVLA flux density reported by other authors at the same frequency and epoch of our observations. This discrepancy could be due to extended emission detected with the EVLA or to calibration problems in the VLBI and/or EVLA observations.Comment: Letter. Accepted in A&

El empleo de hogar: desigualdad y poder entre mujeres / Domestic service: inequality and power among women

RESUMEN: El tema escogido para este artículo es el análisis de la peculiar relación laboral que se establece entre mujeres en el caso del empleo de hogar; una relación que, para empleadas y empleadoras, se presenta como algo más que un trabajo, pero algo menos que un empleo. El empleo de hogar genera una situación de dependencia asimétrica entre mujeres que constituye un escenario óptimo para observar cómo las desigualdades derivadas de la división sexual del trabajo (desigualdades inter-géneros) se presentan atravesadas por las de clase y etnia (desigualdades intra-género) en un contexto de capitalismo global. ASBTRACT: The main topic of this article is the analysis of the particular work relationship that is established between women in the case of domestic paid work. This relationship between employees and employers is more than work, but less than employment. Domestic paid work generates a situation of asymmetrical dependence between women that represents a perfect scenario to observe how inequalities derived from sexual division of work (inter gender inequalities) are crossed by those of class and ethnic group (intra gender inequalities) in a context of global capitalism

Computer Networks Virtualization with GNS3: Evaluating a solution to optimize resources and achieve a distance learning

Designing educational resources allow students to modify their learning process. In particular, on-line and downloadable educational resources have been successfully used in engineering education the last years [1]. Usually, these resources are free and accessible from web. In addition, they are designed and developed by lecturers and used by their students. But, they are rarely developed by students in order to be used by other students. In this work-in-progress, lecturers and students are working together to implement educational resources, which can be used by students to improve the learning process of computer networks subject in engineering studies. In particular, network topologies to model LAN (Local Area Network) and MAN (Metropolitan Area Network) are virtualized in order to simulate the behavior of the links and nodes when they are interconnected with different physical and logical design.This work is supported by the “Computer Science Research Institute” of the University of Alicante through the aid “Internationalization and quality of the doctoral program”

Effects of red wine and different doses of polyphenols from dealcoholised red wine on endothelial function in subjects with metabolic syndrome

Podeu consultar el III Workshop anual INSA-UB complet a: http://hdl.handle.net/2445/118993Sessió 1. Pòster núm.

Metabolic fingerprint after acute and under sustained consumption of a functional beverage based on grape skin extract in healthy human subjects

Grape-derived polyphenols are considered to be one of the most promising ingredients for functional foods due to their health-promoting activities. We applied a HPLC-MS-based untargeted metabolomic approach in order to evaluate the impact of a functional food based on grape skin polyphenols on the urinary metabolome of healthy subjects. Thirty-one volunteers participated in two dietary crossover randomized intervention studies: with a single-dose intake (187 mL) and with a 15-day sustained consumption (twice per day, 187 mL per day in total) of a functional beverage (FB). Postprandial (4-hour) and 24-hour urine samples collected after acute consumption and on the last day of sustained FB consumption, respectively, were analysed using an untargeted HPLC-qTOF-MS approach. Multivariate modelling with subsequent application of an S-plot revealed differential mass features related to acute and prolonged consumption of FB. More than half of the mass features were shared between the two types of samples, among which several phase II metabolites of grape-derived polyphenols were identified at confidence level II. Prolonged consumption of FB was specifically reflected in urine metabolome by the presence of first-stage microbial metabolites of flavanols: hydroxyvaleric acid and hydroxyvalerolactone derivatives. Overall, several epicatechin and phenolic acid metabolites both of tissular and microbiota origin were the most representative markers of FB consumption. To our knowledge, this is one of the first studies where an untargeted LC-MS metabolomic approach has been applied in nutrition research on a grape-derived FB

Preparació d'un organocatalitzador dendrimèric

Els organocatalitzadors, en quantitats subestequiomètriques, són especies orgàniques que permeten accelerar reaccions químiques. Per tal d'aconseguir una química més sostenible, un dels reptes dels científics del nostre temps, és poder recuperar aquests catalitzadors de forma fàcil, tant per poder-los reutilitzar (sobre tot si són cars) com per simplificar els processos de purificació dels productes desitjats. En el treball que es presenta ens hem centrat en la preparació d'un organocatalitzador dendrimèric amb grups cinchonina a la seva superfície. Els derivats de cinchona són barats i comercialment assequibles i a més s'han emprat en moltes reaccions com organocatalitzadors. Els dendrímers, son unes molècules arborescents que poden ser emprades com a suports de catalitzadors. Concretament els dendrímers fosforats són solubles en solvents orgànics convencionals, però es poden precipitar i recuperar fàcilment, afegint grans quantitats de pentà a la mostra. Aquesta propietat els fa uns bons suports fàcilment recuperables per a catalitzadors, que poden actuar en condicions homogènies. Per portar a terme el nostre objectiu, hem hagut de modificat l'estructura de la cinchonina a través del seu grup vinil, utilitzant una reacció radicalària amb un tiol alifàtic. Aquest tiol a més aportava a la seva estructura un grup fenol que ens ha servit per ancorar aquesta molècula a un dendrímer fosforat de primera generació, com es pot veure a la figura. Per optimitzar les condicions de reacció, s'ha utilitzat inicialment una molècula model amb grups funcionals similars als de la superfície del dendrímer que ens interessava. Tots els compostos nous preparats en aquest treball que contenen l'estructura de cinchonina han estat assajats com a catalitzadors en una reacció de Michael. S'ha pogut veure que quan actuen en heterofase els temps de reacció són molt llargs comparats amb la cinchonina model, però quan ho fan en fase homogènia, són molt actius i es poden recuperar de forma pràcticament quantitativa