Segregation-induced grain boundary electrical potential in ionic oxide materials: A first principles model

A first principles continuum analytical model for cationic segregation to the grain boundaries in complex ceramic oxides is presented. The model permits one to determine the electric charge density and the segregation-induced electric potential profiles through the grain and can be extrapolated to the range of nanostructured grain sizes. The theoretical predictions are compared with existing data for yttria-stabilized tetragonal zirconia polycrystals. The implications for physical properties (mainly high temperature plasticity and hardening behaviour) are then discussed.Gobierno de España MAT2009-14351-C02-01, MAT2009-14351-C02-0

Cosmological Bianchi Class A models in S\'aez-Ballester theory

We use the S\'aez-Ballester (SB) theory on anisotropic Bianchi Class A cosmological model, with barotropic fluid and cosmological constant, using the Hamilton or Hamilton-Jacobi approach. Contrary to claims in the specialized literature, it is shown that the S\'aez-Ballester theory cannot provide a realistic solution to the dark matter problem of Cosmology for the dust epoch, without a fine tunning because the contribution of the scalar field in this theory is equivalent to a stiff fluid (as can be seen from the energy--momentum tensor for the scalar field), that evolves in a different way as the dust component. To have similar contributions of the scalar component and the dust component implies that their past values were fine tunned. So, we reinterpreting this null result as an indication that dark matter plays a central role in the formation of structures and galaxy evolution, having measureable effects in the cosmic microwave bound radiation, and than this formalism yield to this epoch as primigenius results. We do the mention that this formalism was used recently in the so called K-essence theory applied to dark energy problem, in place to the dark matter problem. Also, we include a quantization procedure of the theory which can be simplified by reinterpreting the theory in the Einstein frame, where the scalar field can be interpreted as part of the matter content of the theory, and exact solutions to the Wheeler-DeWitt equation are found, employing the Bianchi Class A cosmological models.Comment: 24 pages; ISBN: 978-953-307-626-3, InTec

Deployment of Digital Video and Audio Over Electrical SCADA Networks

With the arrival of new hardware and software technologies, supervisory control and data acquisition human-machine interfaces (SCADA/HMI), usually text-based, can now benefit from the advantages the inclusion of multimedia information brings. However, due to the special requirements imposed by such systems, integrating audio and video data into the SCADA interfaces is not a trivial task. In this document we analyze those special characteristics and propose solutions so this integration is possible in power systems communication.Ministerio de Ciencia y Tecnología TIC2000-0367-P4-0

Levels of Physical Activity during School Hours in Children and Adolescents: A Systematic Review

Background: This systematic reviewdetermines the levels of physical activity (PA) during school hours in children and adolescents.Methods: Studies carried out fromJanuary 1987 toDecember 2019were retrieved from four databases (Web of Science, Pubmed, Scopus and SportDiscus). Results: Twenty-nine studies were included in this systematic review. Most of them used accelerometers and showed that male and female children accumulated a mean of between 14 and 68 min of moderate-to-vigorous PA (MVPA) during school hours (3–22% of this daily segment), andmale and female adolescents accumulated amean of between 13 and 28min ofMVPA during this daily segment (3–8% of the school hours). Less than a quarter of children and adolescents reached the recommended 30 min of MVPA during school hours, with notable differences between sexes. Conclusions: These results suggest that the levels of PA during school hours are not enough, and consequently, schools should develop strategies for helping children and adolescents reach the school PA recommendation

Maturity model based on CMMI for governance and management of Green IT

Sustainability is a problem that is increasingly worrying organisations around the world, which has led them to adopt sustainable practices in their processes. From the point of view of one of the areas that have had the greatest impact in recent times in organisations, the area of information technology (IT), different sustainable practices have arisen in isolation, known as Green IT practices. So, a framework that organises and establishes these practices (until now isolated) is necessary in order to implement, assess, and improve the Green IT in organisations in an efficient, gradual, and integrated way. In this study, the authors propose a maturity model based on capability maturity model integration (CMMI), through which it is intended to help organisations gradually implement and improve through different levels of maturity, the governance and management of Green IT. The validations of this proposal carried out through experts and practical cases demonstrate the usefulness of this proposal when implementing, assessing, and improving the Green IT in organisations

EFFECTS OF LEVELS OF INSOLUBLE AND SOLUBLE FIBRE IN DIETS FOR GROWING RABBITS ON FAECAL DIGESTIBILITY, NITROGEN RECYCLING AND IN VITRO FERMENTATION

[EN] The effect of neutral detergent fibre (NDF) and neutral detergent soluble fibre (NDSF) on in vivo faecal digestibility and caecal fermentation pattern was studied in growing rabbits, in four diets formulated according to two levels of NDF, 370 (LI) and 450 (HI) g/kg, and two levels of NDSF, 150 (LS) and 180 (HS) g/kg in substitution of starch, in a 2x2 factorial structure. Twenty four New Zealand White rabbits weaned at 28 d (630 ± 80.2 g weight) were allocated to digestibility cages from 42 to 49 d of age to determine apparent faecal digestibility of each diet (n=6). Urine was collected for determination of purine derivatives (PD). Once the digestibility trial finished, rabbits were fitted with PVC neck collars for 24 h total caecotrophe collection. After one day of recovery, animals were slaughtered and caecal contents were used as inocula for 18 h in vitro gas production and caecal degradation (ivDMcD) study, using an HCl-pepsin and pancreatin pre-digested substrate. Diet digestibility was also determined by the in vitro three-step enzymatic procedure. There were no effects of the NDF x NDSF interaction for any digestibility parameter (P>0.10). Both dry matter and organic matter digestibility (DMD and OMD) decreased from 0.518 to 0.442 and from 0.526 to 0.447, respectively, with the inclusion of NDF (P0.10). In contrast, NDF digestibility (NDFD) and ivDMcD did not respond to NDF (P>0.10) but increased from 0.156 to 0.200 and 0.141 to 0.210 with a ratio of NDSF (P<0.01). Weight of caecal contents increased with both NDF (P<0.001) and NDSF (P<0.01). However, total production of caecotrophes increased from 20.1 to 25.5 g DM/d with NDF (P<0.05), but was not affected by NDSF. The crude protein (CP) proportion in caecotrophes decreased with NDF (P<0.001) and increased with NDSF (P<0.01), and total CP recycled as caecotrophes tended (P=0.093) to be higher in HS diets, being unaffected by the dietary level of NDF. Diets rich in NDSF rendered higher gas volumes (P<0.001) than those with LS from 2 to 18 h incubation, whereas inclusion of high proportions of NDF reduced gas volume (P<0.01). Results indicate that NDF reduces faecal digestibility, whereas NDSF promotes better conditions for caecal fermentation.This work was financed through the Project AGL2006-07596, from the Ministry of Education and Science (Spanish Government). Ms. Norelys Rodríguez-Romero’s stage at in the University of Zaragoza was financed though a Doctoral fellowship from the Universidad Nacional Experimental del Táchira (Venezuela)Rodríguez-Romero, N.; Abecia, L.; Fondevila, M.; Balcells, J. (2011). EFFECTS OF LEVELS OF INSOLUBLE AND SOLUBLE FIBRE IN DIETS FOR GROWING RABBITS ON FAECAL DIGESTIBILITY, NITROGEN RECYCLING AND IN VITRO FERMENTATION. World Rabbit Science. 19(2):85-94. https://doi.org/10.4995/wrs.2011.828SWORD859419