Psychological elements explaining the consumer's adoption and use of a website recommendation system: A theoretical framework proposal

The purpose of this paper is to understand, with an emphasis on the psychological perspective of the research problem, the consumer's adoption and use of a certain web site recommendation system as well as the main psychological outcomes involved. The approach takes the form of theoretical modelling. Findings: A conceptual model is proposed and discussed. A total of 20 research propositions are theoretically analyzed and justified. Research limitations/implications: The theoretical discussion developed here is not empirically validated. This represents an opportunity for future research. Practical implications: The ideas extracted from the discussion of the conceptual model should be a help for recommendation systems designers and web site managers, so that they may be more aware, when working with such systems, of the psychological process consumers undergo when interacting with them. In this regard, numerous practical reflections and suggestions are presented

Effect of Bentonite Addition to Pedro Ximénez White Grape Musts before Their Fermentation with Selected Yeasts on the Major Volatile Compounds and Polyols of Wines and Tentative Relationships with the Sensorial Evaluation

In this work, we study the effect of bentonite addition to the grape must before alcoholic fermentation on the chemical composition and sensorial profile of the obtained wines. Fermentations were carried out with two Saccharomyces cerevisiae commercial active dry yeasts treated or not with bentonite and were compared with a control wine obtained by spontaneous fermentation (using the grape must microbiota). Several significant effects on the chemical and sensorial attributes were established by statistical treatments. The selection by multiple variable analysis of seven volatile molecules (ethyl acetate; methanol; 1-propanol; isobutanol; 2-methyl-1-butanol; 3-metyl-1-butanol and 2-phenylethanol) provided several footprints that provide an easy visualization of bentonite effects on wine volatile compounds. A Principal Component Analysis carried out with all the compounds quantified by Gas-Chromatography revealed that the first two Principal Components explain 60.15 and 25.91%, respectively, of the total variance and established five groups that match with the five wines analyzed. Lastly, predictive models at p ≤ 0.05 level for the attributes sight, smell and taste were obtained by Partial Least Squared regression analysis of selected chemical variables

Protected indications of origin as differentiation cue of food products: the Spanish .

The "country/region of origin" is a traditionally strategy used by food companies in order to differentiate their production from each other. In Spain, there are more than 140 EU recognised- Designations of Origin comprising several categories of food and drinks. From these, there are only six quality labels on Spanish dry-cured ham. In spite of this lower number of Designations, they suppose almost the 15% of the global economic value. From both a quantitative and a qualitative perspective -based on a SWOT analysis, this paper traits to analyse the role of origin as a marketing differentiation tool. In addition, interesting recommendations are offered in order to enhance the consumer's knowledge of Designations' main characteristics.Differentiation; Protected Designations of Origin, Protected Geographical Indications

Evaluating the impact of a novel message dissemination scheme for vehicular networks using real maps

[EN] In traffic safety applications for vehicular ad hoc networks (VANETs), some warning messages have to be urgently disseminated in order to increase the number of vehicles receiving the traffic warning information. In those cases, redundancy, contention, and packet collisions due to simultaneous forwarding (usually known as the broadcast storm problem) are prone to occur. In the past, several approaches have been proposed to solve the broadcast storm problem in multi-hop wireless networks such as Mobile ad hoc Networks (MANETs). Among them we can find counter-based, distance-based, locationbased, cluster-based, and probabilistic schemes, which have been mainly tested in non-realistic simulation environments. In this paper, we present the enhanced Message Dissemination based on Roadmaps (eMDR), a novel scheme specially designed to increase the percentage of informed vehicles and reduce the notification time; at the same time, it mitigates the broadcast storm problem in real urban scenarios. We evaluate the impact that our scheme has on performance when applied to VANET scenarios based on real city maps, and the results show that it outperforms previous schemes in all situations. 2012 Elsevier Ltd. All rights reserved.This work was partially supported by the Ministerio de Ciencia e Innovacion, Spain, under Grant TIN2011-27543-C03-01, and by the Diputacion General de Aragon, under Grant "subvenciones destinadas a la formacion y contratacion de personal investigador".Fogue, M.; Garrido, P.; Martínez, FJ.; Cano Escribá, JC.; Calafate, CT.; Manzoni, P. (2012). Evaluating the impact of a novel message dissemination scheme for vehicular networks using real maps. Transportation Research Part C: Emerging Technologies. 25(80):61-80. https://doi.org/10.1016/j.trc.2012.04.017S6180258

Accountability of the media as seen by Spanish citizens

This article analyses the opinions of citizens on the core values of the so-called Media accountability: truthfulness, independence, transparency, public participation and respect for peoples’ rights. It also analyses citizens’ perceptions of various deontological instruments to measure the effectiveness of compliance with these ethical values. The qualitative methodology used to carry out this analysis is part of the R+D+I research project “Accountability and Journalistic Cultures project in Spain. Impact and proposal of good practices in the Spanish media” (MediaACES), which has been achieved through six focus groups in different Spanish cities. The results of the analysis reflect the critical spirit of citizens towards the media due to the following factors: the absence of objectivity, the mixture of economic interests with their editorial line and an ambiguous participation of the public, which requires a better definition of their role within the information process. The conclusions derived from this analysis allow us to reflect on several aspects: among others, the competition in a deregulated market leads to infotainment and affects the quality of information, as well as the rights of people affected by the news. At the same time, the excess of information channels leads to greater disinformation, under the appearance of a spontaneous pluralism that is superfluous. Ethics, therefore, seems to be a necessary requirement to differentiate professional journalism from other inappropriate information channels and to guarantee the right to information of citizens.El presente artículo analiza las opiniones de los ciudadanos sobre los valores centrales de la denominada Media Accountability: veracidad, independencia, transparencia, participación del público y respeto a los derechos de las personas. Asimismo, se estudia la percepción de la ciudadanía hacia diversos instrumentos deontológicos para medir la eficacia del cumplimiento de dichos valores éticos. La metodología cualitativa empleada para realizar este análisis, enmarcado en el proyecto I+D+i “Accountability y Culturas Periodísticas en España. Impacto y propuesta de buenas prácticas en los medios de comunicación españoles” (MediaACES), se ha concretado mediante la realización de seis grupos de discusión (focus groups) en diversas ciudades del territorio español. Los resultados reflejan el espíritu crítico de la ciudadanía hacia los medios de comunicación por los siguientes factores: la ausencia de objetividad, la mezcla de intereses económicos con su línea editorial y una ambigua participación del público, que exige definir mejor su rol dentro del proceso informativo. Las conclusiones permiten reflexionar sobre diversos aspectos, entre otros, que la competencia en un mercado desregularizado conduce al infoespectáculo y afecta a la calidad informativa y los derechos de las personas afectadas por las noticias. Asimismo, el exceso de canales de información conduce a una mayor desinformación, bajo la apariencia de un pluralismo espontáneo que resulta superfluo. La ética, por tanto, se antoja como una exigencia necesaria para distinguir el periodismo profesional de otras opciones informativas impropias y garantizar el derecho a la información de los ciudadanos

Propiedades de transmisión de electrones de Dirac a través de superredes Cantor en grafenoTransmission properties of Dirac electrons through Cantor monolayer graphene superlattices

In this work we use the transfer matrix method to studythe tunneling of Dirac electrons through aperiodic monolayer graphene superlattices. We consider a graphene sheet deposited on top of slabs of Silicon-Oxide (SiO2) and Silicon-Carbide (SiC) substrates, in which we applied the Cantor’s series. We calculatethe transmittance for different fundamental parameters such as: starting width, incident energy, incident angle and generation number of the Cantor’s series. In this case, the transmittance as function of energy presents self-similar features as a function of the generation number. We also compute the angular distribution of the transmittance for fixed energies finding a self-similar patterns between generations. Finally, we calculate the scaling factor for some transmittance spectra, which effectively show scalability.En este trabajo usamos el método de la matriz de transferencia para estudiar el tunelamiento de los electrones de Dirac a través de superredes aperiodicas en grafeno. Consideramosuna hoja de grafeno depositada encima de bloques de sustratos de Óxido de Silicio (SiO2) y Carburo de Silicio (SiC), en los cuales aplicamos la serie de Cantor. Calculamos la transmitancia para diferentes parámetros fundamentales tales como: ancho de partida, energía de incidencia, ángulo de incidencia y número de generación de la serie de Cantor. En este caso, la transmitancia como función de la energía presenta rasgos autosimilares al variar el número de generación. También computamos la distribución angular de la transmitancia para energías fijas econtrando un patrón autosimilar entre generaciones. Por último, calculamos los factores de escala para algunos espectros de la transmitancia, los cuales efectivamente muestran escalabilida

Propiedades de transmisión de electrones de Dirac a través de superredes Cantor en grafeno

En este trabajo usamos el método de la matriz de transferencia para estudiar el tunelamiento de los electrones de Dirac a través de superredes aperiodicas en grafeno. Consideramos una hoja de grafeno depositada encima de bloques de sustratos de Óxido de Silicio (SiO2) y Carburo de Silicio (SiC), en los cuales aplicamos la serie de Cantor. Calculamos la transmitancia para diferentes parámetros fundamentales tales como: ancho de partida, energía de incidencia, ángulo de incidencia y número de generación de la serie de Cantor. En este caso, la transmitancia como función de la energía presenta rasgos autosimilares al variar el número de generación. También computamos la distribución angular de la transmitancia para energías fijas econtrando un patrón autosimilar entre generaciones. Por último, calculamos los factores de escala para algunos espectros de la transmitancia, los cuales efectivamente muestran escalabilidad.In this work we use the transfer matrix method to study the tunneling of Dirac electrons through aperiodic monolayer graphene superlattices. We consider a graphene sheet deposited on top of slabs of Silicon-Oxide (SiO2) and Silicon-Carbide (SiC) substrates, in which we applied the Cantor's series. We calculate the transmittance for different fundamental parameters such as: starting width, incident energy, incident angle and generation number of the Cantor's series. In this case, the transmittance as function of energy presents self-similar features as a function of the generation number. We also compute the angular distribution of the transmittance for fixed energies finding a self-similar patterns between generations. Finally, we calculate the scaling factor for some transmittance spectra, which effectively show scalability

Adaptación de los métodos de enseñanza a los métodos de aprendizaje de los alumnos

El actual proceso de adaptación al Espacio Europeo de Educación Superior (EEES) que estamos viviendo en la Universidad, y que tiene como objetivo favorecer la convergencia europea en materia de educación universitaria, ha destacado algunos aspectos que pueden ser cambiados por parte de los docentes en aras de mejorar el proceso de enseñanza/ aprendizaje. En el presente artículo, presentamos unas directrices que pueden ayudar a los docentes a adaptar los métodos de enseñanza, para que se adecúen al máximo a las capacidades de aprendizaje de los alumnos que cursan sus asignaturas.Peer Reviewe

Changes in nutrient balance, methane emissions, physiologic biomarkers, and production performance in goats fed different forage-to-concentrate ratios during lactation

[EN] The objective was to determine the effect forage-to-concentrate (F:C) ratio and stage of lactation on methane emissions, digestibility, nutrient balance, lactation performance, and metabolic responses in lactating goats. Twenty Murciano-Granadina dairy goats were used in an experiment divided into 3 periods: early (30 d), mid (100 d), and late (170 d) lactation. All goats were fed a diet with 35:65 F:C (FCL) during early-lactation. Then, 1 group (n = 10 goats) remained on FCL through mid- and late-lactation while the other group (n = 10 goats) was fed a diet with 50:50 F:C at mid-lactation (FCM) and 65:35 (FCH) at late lactation. A greater proportion of concentrate in the diet was associated with greater overall intake and digestibility (P < 0.05). Energy balance was negative in early-lactation (-77 kJ/kg of BW0.75, on average) and positive for FCL at mid- and late-lactation (13 and 35 kJ/kg of BW0.75, respectively). Goats fed FCM and FCH maintained negative energy balance throughout lactation. Plasma concentrations of non-esterified fatty acids at mid-lactation were greater for FCM than FCL (680 mEq/L), and at late-lactation concentrations were greater for FCH and FCL (856 mEq/L). A similar response was detected for plasma beta-hydroxybutyrate. Methane emission was greater (P < 0.05) for FCM than FCH (1.7 g CH4/d). This study demonstrated that differences in F:C across stages of lactation lead to distinct metabolic responses at the level of the rumen and tissues.This study was supported by LIFE Project, European Commission (ref. LIFE2016/CCM/ES/000088 LOW CARBON FEED).Fernández Martínez, CJ.; Hernández, A.; Gomis-Tena Dolz, J.; Loor, JJ. (2021). Changes in nutrient balance, methane emissions, physiologic biomarkers, and production performance in goats fed different forage-to-concentrate ratios during lactation. Journal of Animal Science. 99(7):1-13. https://doi.org/10.1093/jas/skab114S11399

Tracer test modeling for characterizing heterogeneity and local-scale residence time distribution in an artificial recharge site

Artificial recharge of aquifers is a technique for improving water quality and increasing groundwater resources. Understanding the fate of a potential contaminant requires knowledge of the residence time distribution (RTD) of the recharged water in the aquifer beneath. A simple way to obtain the RTDs is to perform a tracer test. We performed a pulse injection tracer test in an artificial recharge system through an infiltration basin to obtain the breakthrough curves, which directly yield the RTDs. The RTDs turned out to be very broad and we used a numerical model to interpret them, to characterize heterogeneity, and to extend the model to other flow conditions. The model comprised nine layers at the site scaled to emulate the layering of aquifer deposits. Two types of hypotheses were considered: homogeneous (all flow and transport parameters identical for every layer) and heterogeneous (diverse parameters for each layer). The parameters were calibrated against the head and concentration data in both model types, which were validated quite satisfactorily against 1,1,2-Trichloroethane and electrical conductivity data collected over a long period of time with highly varying flow conditions. We found that the broad RTDs can be attributed to the complex flow structure generated under the basin due to three-dimensionality and time fluctuations (the homogeneous model produced broad RTDs) and the heterogeneity of the media (the heterogeneous model yielded much better fits). We conclude that heterogeneity must be acknowledged to properly assess mixing and broad RTDs, which are required to explain the water quality improvement of artificial recharge basins.Peer ReviewedPostprint (published version