H2_2 dissociation over Au-nanowires and the fractional conductance quantum

The dissociation of H$_2$ molecules on stretched Au nanowires and its effect on the nanowire conductance are analyzed using a combination of Density Functional (DFT) total energy calculations and non-equilibrium Keldish-Green function methods. Our DFT simulations reproduce the characteristic formation of Au monoatomic chains with a conductance close to % the conductance quantum $G_0 = 2e^2/h$. These stretched Au nanowires are shown to be better catalysts for H$_2$ dissociation than Au surfaces. This is confirmed by the nanowire conductance evidence: while not affected practically by molecular hydrogen, atomic hydrogen induces the appearance of fractional conductances ($G \sim 0.5 G_0$) as observed experimentally.Comment: 4 pages, 3 figure

Graph Signal Processing: Overview, Challenges and Applications

Research in Graph Signal Processing (GSP) aims to develop tools for processing data defined on irregular graph domains. In this paper we first provide an overview of core ideas in GSP and their connection to conventional digital signal processing. We then summarize recent developments in developing basic GSP tools, including methods for sampling, filtering or graph learning. Next, we review progress in several application areas using GSP, including processing and analysis of sensor network data, biological data, and applications to image processing and machine learning. We finish by providing a brief historical perspective to highlight how concepts recently developed in GSP build on top of prior research in other areas.Comment: To appear, Proceedings of the IEE

Parental Supervision: Predictive Variables of Positive Involvement in Cyberbullying Prevention

From an increasingly early age, parents face the challenge of educating their sons and daughters to act in the world of offline and online relationships. If for professional educators it is not proving easy, the involvement and guidance of parents in their children′s use of the internet seems to be a complex and unexplored challenge. This work aims to analyse the variables that influence digital education and determine a predictive model of positive parental involvement. This study was done with a representative sample consisting of five hundred and ninety-six families (596), representing the parents of children from schools with similar socio-cultural indexes. To do this, and using self-report instruments convertible into independent scales, four predictor variables were analysed: (1) parental knowledge of cyberbullying; (2) perception of parental competence in this regard; (3) parental perception of online risks; and (4) the attribution of parental responsibility in digital education. A structural equations model (SEM) examined the predictive value of these variables with respect to positive parental involvement. The structural equations model confirmed direct and mediated relationships between the independent and mediating variables on the dependent variable: parental supervision. The results indicate that positive parental involvement can be predicted from higher scores in parental knowledge of cyberbullying, perception of parental competence, risk adjustment, and attribution of parental responsibility

Comparative analysis of load profile between small-sided games and official matches in youth soccer players

Los propósitos del presente estudio son: a) Caracterizar la carga externa (eTL) e interna (iTL) de los partidos oficiales y de los partidos de flanco pequeño (SSG) en relación con su objetivo, b) comparar las exigencias entre las SSG y c) analizar los requisitos de las SSG en relación con los partidos oficiales durante un período de competición de un mes. Se registraron 20 jugadores de fútbol de nivel nacional menores de 18 años utilizando dispositivos inerciales WIMUTM (RealTrack Systems, Almería, España) durante cuatro partidos oficiales y 12 sesiones de entrenamiento en los que se realizaron cuatro SSG con objetivos diferentes: (SSG1) manteniendo el balón; (SSG2) manteniendo el balón y progresando; (SSG3) manteniendo el balón, progresando y terminando en mini-goles; y (SSG4) manteniendo el balón, progresando y terminando en un gol oficial con un portero. El análisis estadístico incluyó la H de Kruskall-Wallis y la U de Mann-Whitney con el tamaño del efecto d de Cohen. Los SSG presentaron movimientos de intensidad de caminata y trote (0,7-7 a 7-14 km/h), con un 5 a 8 %HIA (actividad de alta intensidad, >16 km/h), donde predominaron las aceleraciones, desaceleraciones e impactos de baja intensidad (1-2,5 m/s2; 5-7 G), y el %HRMAX (porcentaje de frecuencia cardíaca máxima) se situó entre el 70-90%. Sólo el SSG4 presentó demandas similares a la competencia, encontrando diferencias entre los SSG (p 16 km/h), where low intensity accelerations, decelerations and impacts were predominant (1–2.5 m/s2; 5–7 G), and %HRMAX (maximum heart rate percentage) was between 70–90%. Only SSG4 presented similar demands to competition, finding differences between SSGs (p < 0.05; d = 1.40 − 0.36). In conclusion, the objective of the SSGs directly influenced the demands on the players in training sessions. For this reason, it is important to monitor demands for designing specific training sessions.• Ministerio de Educación, Cultura y Deportes. Beca FPU17/00407, para Carlos David Gómez Carmona • Junta de Extremadura y Fondo Social Europeo. Ayuda GR15122peerReviewe

Natural food ingredients from quince peel: Towards a "zero-waste" production system

The resources on our planet are finite and limited. Nonetheless, more and more waste is being produced worldwide. In this sense, it is essential to acquire circularity and "zero waste" approaches to move from the current environmentally unsustainable agri-food system to a more sustainable practice. Quince is the yellow fruit of the deciduous tree Cydonia oblonga Mill. This fruit has an intense aroma, flavor and acidity, but most varieties are too sour and astringent to be eaten raw, so it is usually processed into marmalade and many other food products, mostly sweets, through processes that discard the peel as a by-product. Therefore, this work was carried out to promote the upcycling of quince peel into valuable food ingredients following a "zero waste" approach. Thus, it was intended to optimize the extraction of compounds of interest to the food industry using the response surface methodology (RSM).The authors are grateful to the Foundation for Science and Technology (FCT) for financial support through national funds FCT/MCTES (PIDDAC) to CIMO (UIDB/00690/2020 and UIDP/00690/2020) and SusTEC (LA/P/0007/2021); to FCT for the contracts of J. Pinela (CEECIND/01011/2018) and L. Barros (CEEC Institutional). A. Pereira thanks his research grant to the project IntegraValor (POCI-01- 0247-FEDER-072241). This work was financially supported by the project IntegraValor, operation POCI-01-0247-FEDER-072241, co-financed by the European Regional Development Fund (FEDER), through the Operational Program for Competitiveness and Internationalization (POCI) of Portugal2020info:eu-repo/semantics/publishedVersio

Ordovician and Silurian igneous rocks and orthogeneisses in the Catalonian Coastel Ranges

These rocks exhibit calc-alkaline affinities and may have originated by partial melting of the crust in a post-collision, anorogenic setting. Orthogneisses derived from biotite-bearing leucogranites occur within aprobably cambrian heterogeneous series. Petrological and geochemical features suggest that they might be genetically related to the ordovician vulcanites. Basic sills and volcanoclastic rocks occur intercalated within a mainly pelitic formation in the lower part of the Silurian sequence. The silurian igneous rocks are alkali basalts and may reflect an extensional regime

Evaluation of radiography as a screening method for detection and characterisation of congenital vertebral malformations in dogs

Congenital vertebral malformations (CVM) are common in brachycephalic ‘screw-tailed’ dogs; they can be associated with neurological deficits and a genetic predisposition has been suggested. The purpose of this study was to evaluate radiography as a screening method for congenital thoracic vertebral malformations in brachycephalic ‘screw-tailed’ dogs by comparing it with CT. Forty-nine dogs that had both radiographic and CT evaluations of the thoracic vertebral column were included. Three observers retrospectively reviewed the images independently to detect CVMs. When identified, they were classified according to a previously published radiographic classification scheme. A CT consensus was then reached. All observers identified significantly more affected vertebrae when evaluating orthogonal radiographic views compared with lateral views alone; and more affected vertebrae with the CT consensus compared with orthogonal radiographic views. Given the high number of CVMs per dog, the number of dogs classified as being CVM free was not significantly different between CT and radiography. Significantly more midline closure defects were also identified with CT compared with radiography. Malformations classified as symmetrical or ventral hypoplasias on radiography were frequently classified as ventral and medial aplasias on CT images. Our results support that CT is better than radiography for the classification of CVMs and this will be important when further evidence of which are the most clinically relevant CVMs is identified. These findings are of particular importance for designing screening schemes of CVMs that could help selective breeding programmes based on phenotype and future studies

The nitrogen contribution of different plant parts to wheat grains: exploring genotype, water, and nitrogen effects

The flag leaf has been traditionally considered as the main contributor to grain nitrogen. However, during the reproductive stage, other organs besides the flag leaf may supply nitrogen to developing grains. Therefore, the contribution of the ear and other organs to the nitrogen supplied to the growing grains remains unclear. It is important to develop phenotypic tools to assess the relative contribution of different plant parts to the N accumulated in the grains of wheat which may helps to develop genotypes that use N more efficiently. We studied the effect of growing conditions (different levels of water and nitrogen in the field) on the nitrogen contribution of the spike and different vegetative organs of the plant to the grains. The natural abundance of 15 δ N and total N content in the flag blade, peduncle, whole spike, glumes and awns were compared to the 15 δ N and total N in mature grains to trace the origin of nitrogen redistribution to the grains. The 15 δ N and total N content of the different plant parts correlated positively with the 15 δ N and total N content of mature grains suggesting that all organs may contribute a portion of their N content to the grains. The potential contribution of the flag blade to grain N increased (by 46%) as the growing conditions improved, whereas the potential contribution of the glumes plus awns and the peduncle increased (46 and 31%, respectively) as water and nitrogen stress increased. In general, potential contribution of the ear providing N to growing grains was similar (42%) than that of the vegetative parts of the plants (30-40%), regardless of the growing conditions. Thus, the potential ear N content could be a positive trait for plant phenotyping, especially under water and nitrogen limiting conditions. In that sense, genotypic variability existed at least between old (tall) and modern (semidwarf) cultivars, with the ear from modern genotypes exhibiting less relative contribution to the total grain N. The combined use of 15 δ N and N content may be used as an affordable tool to assess the relative contribution of different plant parts to the grain N in wheat

Trust and Privacy Solutions Based on Holistic Service Requirements

The products and services designed for Smart Cities provide the necessary tools to improve the management of modern cities in a more efficient way. These tools need to gather citizens’ information about their activity, preferences, habits, etc. opening up the possibility of tracking them. Thus, privacy and security policies must be developed in order to satisfy and manage the legislative heterogeneity surrounding the services provided and comply with the laws of the country where they are provided. This paper presents one of the possible solutions to manage this heterogeneity, bearing in mind these types of networks, such as Wireless Sensor Networks, have important resource limitations. A knowledge and ontology management system is proposed to facilitate the collaboration between the business, legal and technological areas. This will ease the implementation of adequate specific security and privacy policies for a given service. All these security and privacy policies are based on the information provided by the deployed platforms and by expert system processing