La función ejecutiva de actualización y el rendimiento en comprensión lectora y resolución de problemas

In this investigation, the capacity of the working memory (WM) updating executive function to predict individual differences in reading comprehension and problem solving was analyzed in 5th-graders of Primary Education. In addition, we examined whether this relation is direct or mediated by domain-general or domain-specific variables. For this purpose, a series of tasks was administered to assess fluid intelligence, WM information updating, arithmetic abilities, arithmetic problem solving, lexical processing, and reading comprehension in 49 students aged between 10 and 11 years. The results support the idea that updating is an important predictor of reading comprehension, beyond the influence of domainspecific skills and fluid intelligence. In the case of problem solving, our findings confirm that updating plays an important role although, perhaps due to task content, the relation seems to be mediated by fluid intelligence at this developmental stageEsta investigación analizó, en niños de 5º curso de Educación Primaria, la capacidad predictora de la función ejecutiva de actualización de la Memoria Operativa (MO) en las diferencias individuales en comprensión lectora y resolución de problemas aritméticos. Además, se estudió si esta relación es directa o está mediada por variables de dominio general o específico. Con este fin se administró un conjunto de pruebas que evalúan la inteligencia fluida, la actualización de la información en la MO, la competencia aritmética, la resolución de problemas aritméticos, el procesamiento léxico y la comprensión lectora a 49 alumnos con edades comprendidas entre los 10 y 11 años. Los resultados apoyan la idea que la actualización de la MO es un importante predictor de la comprensión lectora, más allá de la influencia de las habilidades de dominio específico y de la inteligencia fluida. En el caso de la resolución de problemas, nuestros hallazgos confirman que la actualización juega un papel importante aunque, en este momento evolutivo, quizá por el propio contenido de la tarea, la relación parece mediada por la inteligencia fluid

Structure of Thermoreversible Poly(vinyl alcohol) Cryo-Hydrogels as studied by Proton Low Field NMR Spectroscopy

The network structure of Poly(vinyl alcohol) (PVA) hydrogels obtained by freezing-thawing cycles was investigated by solid state 1H low field NMR spectroscopy. By application of multiple-quantum NMR experiments, we obtain information about the segmental order parameter, which is directly related to the restrictions to chain motion (crosslinks) formed upon gelation. These measurements indicate that the network mesh size, as well as the relative amount of non-elastic defects (i.e. non-crosslinked chains, dangling chains, loops) decreases with the number of freezing-thawing cycles, but it is independent of the polymer concentration. The formation of the PVA network is accompanied by an increasing fraction of polymer with fast magnetization decay (∼20μs). The quantitative study of this rigid phase with a specific refocusing pulse sequence shows that it is composed of a primary crystalline polymer phase (around 5%), which constitutes the main support of the network structure and determines the mesh size, and a secondary population of more imperfect crystallites, which increase the number of elastic chain segments in the polymer gel but does not affect the average network mesh size appreciably. Correspondingly, progressive melting of the secondary crystallites with increasing temperature does not affect the network mesh size but only the amount of network defects, and melting of the main PVA crystallites at around 80 ºC leads to destruction of the network gel and formation of an isotropic PVA solution.Peer reviewe

Use of Natural Light vs. Cold LED Lighting in Installations for the Recovery of Victims of Gender Violence: Impact on Energy Consumption and Victims’ Recovery

The efficiency of lighting installations is a major challenge concerning Governments, productive sectors and individuals. However, the importance of accurate lighting in some areas, especially those related to Health and Wellbeing is so critical that the constraints of energy efficiency and sustainability are not always a priority. This situation has become more critical with the current boom in the application of non-visual effects of light to these areas. In this study, the effects oftwo different kinds of lighting on femalevictims of gender violence are compared and analyzed in terms of positive results and impact on energy consumption and sustainability. The lighting technologies used are integrated in facilities where these women carry out different activities aimed at their integration into daily life after their traumatic experiences. The results are expected to become a tool for professionals working with these collectives and for installation designers. In spite of the well-known effects of cold light, especially for tasks involving arousal, sleepiness and other critical variables, it is demonstrated that daylight, which is obviously cheaper from productive and environmental perspectives, is better for this application.This work was conducted under funding from CAPES (Coordination of Improvement of Higher Education Personnel—Brazil) which has granted scholarships Doctoral number BEX 0947/14-8

HispaVeg: a new online vegetation plot database for Spain

We describe a new online database, named HispaVeg, which currently holds data from 2663 vegetation plots of Spanish woodlands, scrublands and grasslands. Unlike other similar databases, a detailed description of the structure is stored with the floristic data of each plot (i.e., number and physiognomy of the vertical layers, cover values for each layer).Most of the vegetation plots are large rectangles (400 to 2000 square meters) with an average of 34 species per plot. The survey dates range from 1956 to present, with most of the records between 1964 and 1994. The elevation of the plots ranges from 0 to 2880, with most of the plots between 300 and 1500 m. HispaVeg is freely available to the scientific community. Users can query the online database, view printable reports for each plot and download spreadsheet-like raw data for subsets of vegetation plots

Investigating Piezochromic Properties of πconjugated Materials: a combined Raman and DFT Study

Π-conjugated materials have been studied for decades due to their great interest in organic electronics. Among them, piezochromic materials, which exhibit color changes resulting from external pressure or mechanical grinding, become very attractive from a scientific viewpoint owing to their potential applications as pressure-sensing and opticalrecording systems1. The main target of the present work is to develop a joint experimental and theoretical approach able to deliver crucial information for the understanding of the structural effects causing piezochromic changes. To this end, we will focus our attention on two families of -conjugated materials with potential application as sensors. The first one is a family of 9,10-Bis((E)-n(pyrid-2-yl)vinyl) anthracene, BPnVA (n=2 orto-,3 metha- and 4 para-) compounds, see Figure 1. Interestingly, these three compounds with varying position of the nitrogen on the external pyridyl group exhibit different molecular packing modes. Grinding and the application of external pressure on the powder also led to a strong change in their photoluminescence color.2 The second familiy is based on the N,N’-Bis-Boc-3,3’-di(pyren-1yl)-2,2’-biindole compound (compound 1c in Figure 1) which also shows photoluminescence under pressure application. However, the molecular packing induced by this phenomenon is still under study 3. In both cases, it will be also very interesting to determine how temperature affects the vibrational structure of these systems.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

The first example of an intramolecular westphal reaction. Synthesis of a new aza-quinolizinium type system

The first example of an intramolecular Westphal condensation is described. To test the utility of this reaction, new benz(f)azino[2,1-a]phthalazinium salts have been prepared from appropriate dicarbonyl precursors.The authors wish to thank the Comisión Interministerial de Ciencia y Tecnología (C.I.C.Y.T.) (Project SAF98-0093) for financial support and one studentship (V. M. B.

Dynamic Permittivity Measurement of Ground-Tire Rubber (GTR) during Microwave-Assisted Devulcanization

[EN] Many efforts are being made to find innovative ways of recycling rubber from end-of-life tires (ELTs), also called ground tire Rubber (GTR). Recycling through devulcanization allows the reintroduction of rubber back into the manufacturing industry. Such a process requires providing enough energy to break the sulfur links, while preventing damage to the polymeric chain. Microwave heating is controllable, efficient, and it does not rely on conventional heating mechanisms (conduction, convection) which may involve high heating losses, but rather on direct dielectric heating. However, to adequately control the microwave-assisted devulcanization performance, a thorough knowledge of the GTR permittivity versus temperature is required. In this work, GTR permittivity was monitored during its devulcanization. A resonant technique based on a dual-mode cylindrical cavity was used to simultaneously heat rubber and measure its permittivity at around 2 GHz. The results show sharp changes in the GTR permittivity at 160 and 190 degrees C. After the GTR cooled down, a shifted permittivity evidences a change in the GTR structure caused by the devulcanization process. Microwave-assisted devulcanization effectiveness is proven through time-domain nuclear magnetic resonance (NMR) measurements, by verifying the decrease in the cross-link density of processed GTR samples compared to the original sample.This research project has received funding from the European Union's Horizon 2020 research and innovation program under grant agreement number 870,000. More information at https://cordis.europa.eu/project/id/870000 (accessed on 27 August 2022) and https://valuerubber.eu/(accessed on 27 August 2022). JLV and FMS also thanks the funding from Ministerio de Ciencia e Innovacion (PID2020-119047RB-I00 y PLEC2021-007793), Gobierno de Aragon (EC-22-2021) and CSIC (201860E045).Pérez-Campos, R.; Fayos-Fernández, J.; Monzó-Cabrera, J.; Martín Salamanca, F.; López Valentín, J.; Catalá Civera, JM.; Plaza González, PJ.... (2022). Dynamic Permittivity Measurement of Ground-Tire Rubber (GTR) during Microwave-Assisted Devulcanization. Polymers. 14(17):1-21. https://doi.org/10.3390/polym14173543121141

Chromatic dispersion compensation using the negative pre-chirping technique through single and dual drive Mach-Zehnder modulators.

En el presente artículo se estudia el uso de moduladores externos Mach-Zehnder de tipo Single Drive y Dual Drive como elemento compensador de dispersión cromática en una red óptica a 10 Gbps a nivel de simulación en la herramienta Optsim™ de RSoft, mediante la técnica de pre-chirping negativo. Para comprobar la validez del estudio se realizó el análisis del comportamiento de la tasa de error de bit, el diagrama del ojo y la duración de los pulsos ópticos de forma comparativa. Los resultados obtenidos evidenciaron las mejoras que presenta el sistema mediante el manejo del chirp de los moduladores.In this paper, the use of Single and Dual Drive Mach-Zehnder external modulators as Chromatic Dispersion compensators in a 10 Gbps optical network at a simulation level in RSoft's Optsim™ tool, by negative pre-chirping technique is studied. To verify the validity of the study, a behavior analysis of the Bit Error Rate, the eye diagram and the duration of the optical pulses in a comparative way was carried out. The obtained results presented improvement in the system through the chirp management of the modulators. Key words: Chromatic dispersion, Mach-Zehnder modulator, negative pre-chirping, chirp, Optsim

Poly(acrylonitrile-co-butadiene) as polymeric crosslinking accelerator for sulphur network formation

The major controlling factors that determine the various mechanical properties of an elastomer system are type of chemical crosslinking and crosslink density of the polymer network. In this study, a catalytic amount of acrylonitrile butadiene copolymer (NBR) was used as a co-accelerator for the curing of polybutadiene (BR) elastomer. After the addition of this copolymer along with other conventional sulphur ingredients in polybutadiene compounds, a clear and distinct effect on the curing and other physical characteristics was noticed. The crosslinking density of BR was increased, as evidenced by rheometric properties, solid-state NMR and swelling studies. The vulcanization kinetics study revealed a substantial lowering of the activation energy of the sulphur crosslinking process when acrylonitrile butadiene copolymer was used in the formulation. The compounds were also prepared in the presence of carbon black and silica, and it was found that in the carbon black filled system the catalytic effect of the NBR was eminent. The effect was not only reflected in the mechanical performance but also the low-temperature crystallization behavior of BR systems was altered. © 2020 The AuthorsMaterials science; Materials chemistry; Crosslinking accelerator; Sulphur network; Solid state NMR; Curing kinetics; Activation energy; Acrylonitrile butadiene; Polybutadiene; Low-temperature; Crystallization. © 2020 The Author

A note on local bases and convergence in fuzzy metric spaces

In the context of fuzzy metrics in the sense of George and Veeramani, we study when certain families of open balls centered at a point are local bases at this point. This question is related to p-convergence and s-convergence. © 2013 Elsevier B.V. All rights reserved.Samuel Morillas acknowledges the support of Universitat Politenica de Valencia under Grant PAID-05-12 SP20120696.Gregori Gregori, V.; Miñana Prats, JJ.; Morillas Gómez, S. (2014). A note on local bases and convergence in fuzzy metric spaces. Topology and its Applications. 163:142-148. https://doi.org/10.1016/j.topol.2013.10.013S14214816