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The increasing presence and relevance of Information and Communications Technology (ICT) in learning scenarios has imposed new demands on teachers, who must be able to design new learning situations while relying on the growing supply of available digital resources. One of the fields that more urgently needs to utilize the potential benefits of ICT to transform learning is sustainability, and more precisely the development of sustainability competences (SCs). Indeed, wider societal changes are needed that ensure a balance between economic growth, respect for the environment, and social justice, and these changes must start with individual action, knowledge, and the capacity and willingness to act (i.e., the definition of “competence”). However, although there is a wide consensus on the fact that education should ensure the acquisition of competences for life, making this a reality may be more problematic. This difficulty stems, partly, from a lack of a definition of the intervening elements (knowledge, skills, values, attitudes) that enables the integration of competences into specific learning sequences and activities. Taking into account all the above and the difficulties that teachers face in choosing relevant resources and incorporating competences into their planning, we propose a series of indicators that serve to characterize the four dimensions of scientific competence: contents of science, contents about science, the value of science, and the utility of science in educational materials. Although primarily intended for filtering multimedia resources in an educational platform, this instrument (as well as the indicators therein) can be extrapolated to the selection and management of a variety of resources and activities, eventually selecting those that are more useful for the acquisition of the scientific competence. They can also provide learning-managers with a common ground to work on by sharing the objectives and indicators related to the acquisition of competences.

Digital competence is one of the eight key competences for life-long learning developed by the European Commission, and is a requisite for personal fulfilment and development, active citizenship, social inclusion, and employment in a knowledge society. To accompany young learners in the development of competence, and to guarantee optimal implementation of information and communication technologies (ICTs), it is necessary that teachers are, in turn, literate. We had 43 secondary school teachers in initial training to assess their own level of competence in 21 sub-competences in five areas identified by the DIGCOMP project, using the rubrics provided in the Common Digital Competence Framework for Teachers (Spanish Ministry of Education). Overall, pre-service teachers’ conceptions about their level of digital competence was low (Initial). Students scored highest in information, which refers mostly to the operations they performed while being students. Secondly, in safety and communication, excluding protection of digital data and preservation of digital identity. Lowest values were achieved in content creation and problem solving, the dimensions most closely related with the inclusion of ICTs to transform teaching-learning processes. The knowledge or skills they exhibit are largely self-taught and, so, we perceive an urgent need to purposefully incorporate relational and didactic aspects of ICT integration.

Bechstein's bat (Myotis bechsteinii) is one of the rarest European bat species. In oceanic climates, they appear to be restricted to woodlands, with preference for mature deciduous forests in lowlands. We investigated habitat selection by 20 lactating females belonging to 13 maternity colonies in Mediterranean landscapes. Deciduous forests (particularly Quercus pyrenaica) were positively selected, and coniferous forests were opportunistically used, whereas no foraging bouts occurred in evergreen broadleaved woodlands or in non-forested areas. Bats preferred to forage inside the forest rather than in edges or clearings. Stands of high canopy cover were also preferred. The preference for deciduous over evergreen broadleaved woodlands suggests that other variables such as prey availability, rather than structural constraints, drive habitat selection. M. bechsteinii might be abundant in well preserved deciduous forests within its Mediterranean range, in which the species' distribution might be limited by habitat loss and degradation related to agricultural practices and deforestation.

In a Geoffroy's bat Myotis emarginatus colony in central Iberia, we investigated the foraging behaviour of six lactating females by means of radio-tracking and the diet of 23 individuals by faecal analysis. The bats preferred to forage mainly in pine plantations, riparian woodland, and scrubland, whereas native dehesa (a loose semi-natural oak Quercus rotundifolia and Q. suber woodland) was not exploited as expected. By far the most important prey type for this bat in the Mediterranean were spiders. We conclude that Geoffroy's bat prefers to forage in multistratified dense habitats, even if these include nonnative plantations. The vertical structuring and especially high cover, along with the combination of both parameters are important for this highly manoeuvrable, clutter-tolerant bat. This is valid even when the vertical component is much reduced as occurs in scrubland, in the first succession steps to woodland creation, and in degraded conditions. Under such circumstances, aerial weaving spiders might be detected and captured when lying in their webs. It is likely that dehesa is too loosely wooded to offer suitable characteristics for orb-weaving aerial spiders to build webs, and thus it may not be as attractive for M. emarginatus as more dense habitats.

The antibacterial and cytotoxic effects of metabolites isolated from an antibacterial extract of Flourensia oolepis were evaluated. Bioguided fractionation led to five flavonoids, identified as 2′,4′-dihydroxychalcone (1), isoliquiritigenin (2), pinocembrin (3), 7-hydroxyflavanone (4), and 7,4′-dihydroxy-3′-methoxyflavanone (5). Compound 1 showed the highest antibacterial effect, with minimum inhibitory concentration (MIC) values ranging from 31 to 62 and 62 to 250 μg/mL, against Gram-positive and Gram-negative bacteria, respectively. On further assays, the cytotoxic effect of compounds 1–5 was determined by MTT assay on acute lymphoblastic leukemia (ALL) and chronic myeloid leukemia (CML) cell lines including their multidrug resistant (MDR) phenotypes. Compound 1 induced a remarkable cytotoxic activity toward ALL cells (IC50 = 6.6–9.9 μM) and a lower effect against CML cells (IC50 = 27.5–30.0 μM). Flow cytometry was used to analyze cell cycle distribution and cell death by PI-labeled cells and by Annexin V/PI staining, respectively. Upon treatment, 1 induced cell cycle arrest in the G2/M phase accompanied by a strong induction of apoptosis. These results describe for the first time the antibacterial metabolites of F. oolepis extract, with 1 being the most effective. This chalcone also emerges as a selective cytotoxic agent against sensitive and resistant leukemic cells, highlighting its potential as a lead compound.

We examined the effects of the flavonoids pinocembrin and quercetin on the feeding behavior, survival, and development of the Cucurbitaceae pest Epilachna paenulata (Coleoptera: Coccinellidae). In no-choice experiments, 48 hr-consumption of Cucurbita maxima Duch. leaves treated with pinocembrin at 1, 5, and 50 μg/cm² was less than one third of that for leaves treated with 0.1 μg/cm² of pinocembrin or untreated leaves. Larvae stopped feeding after 9 days of high doses of pinocembrin (5 and 50 μg/cm²), and larval weight and survival were negatively affected by pinocembrin at 1-50 μg/cm². Delayed mortality in comparison to food-deprived larvae suggests that the mechanism of action for pinocembrin is chronic intoxication, rather than simple starvation from antifeedant effects. In contrast, leaf consumption and larval weight were not significantly affected by quercetin (at 0.1, 1, 5, and 50 μg/cm²) while mortality rates were only slightly increased. The response of E. paenulata larvae in a choice-test to combinations of pinocembrin at antifeedant doses (5 and 50 μg/cm²) and quercetin at phagostimulant doses (0.01 and 0.1 μg/cm²) indicated that the feeding deterrent activity of the former completely overshadowed the stimulant activity of the latter. These results demonstrate the different responses of one insect species to two widely distributed plant flavonoids. Pinocembrin strongly affected survival of E. paenulata while quercetin had only a weak effect without major consequences on the insect life-cycle.

Bioassay-guided fractionation of an ethanolic extract of the aerial parts of Dolichandra cynanchoides Cham. (Bignoniaceae) led to the isolation of a natural wax with anti-insect activity against Spodoptera frugiperda (Noctuidae) and Epilachna paenulata (Coleptera). The compound was identified spectroscopically as an ester of a C27 fatty acid and a C25 alcohol, pentacosyl heptacosanoate (1). The effective doses of 1 for 50% feeding inhibition (ED50) of S. frugiperda and E. paenulata were 0.82 and 8.53 µg/cm2, respectively, in a choice test, while azadirachtin showed ED50 of 0.10 and 0.59 µg/cm2, respectively. In a no-choice test, both insects refused to feed on leaves treated with 1 at doses of 0.1 µg/cm2 or greater inhibiting larval growth and dramatically reducing survival. The lethal doses 50 (LD50) of 1 were 0.39 and 0.68 µg/cm2 for S. frugiperda and E. paenulata, respectively. These results indicate that 1 has potential for development as botanical insecticides. Similar esters might be obtainable in large quantities as many edible crops produce wax esters that are discarded during food processing. Research on these materials could lead to the detection of similar waxes with insecticidal activity.

Creating biofunctional artificial scaffolds could potentially meet the demand of patients suffering from bone defects without having to rely on donors or autologous transplantation. Three-dimensional (3D) printing has emerged as a promising tool to fabricate, by computer design, biodegradable polymeric scaffolds with high precision and accuracy, using patient-specific anatomical data. Achieving controlled degradation profiles of 3D printed polymeric scaffolds is an essential feature to consider to match them with the tissue regeneration rate. Thus, achieving a thorough characterization of the biomaterial degradation kinetics in physiological conditions is needed. Here, 50:50 blends made of poly(ε-caprolactone)–Poly(D,L-lactic-co-glycolic acid (PCL-PLGA) were used to fabricate cylindrical scaffolds by 3D printing (⌀ 7 × 2 mm). Their hydrolytic degradation under static and dynamic conditions was characterized and quantified. For this purpose, we designed and in-house fabricated a customized bioreactor. Several techniques were used to characterize the degradation of the parent polymers: X-ray Photoelectron Spectroscopy (XPS), Gel Permeation Chromatography (GPC), Scanning Electron Microscopy (SEM), evaluation of the mechanical properties, weigh loss measurements as well as the monitoring of the degradation media pH. Our results showed that flow perfusion is critical in the degradation process of PCL-PLGA based scaffolds implying an accelerated hydrolysis compared to the ones studied under static conditions, and up to 4 weeks are needed to observe significant degradation in polyester scaffolds of this size and chemical composition. Our degradation study and characterization methodology are relevant for an accurate design and to tailor the physicochemical properties of polyester-based scaffolds for bone tissue engineering.

Fe−N−C catalysts are an interesting option for polymer electrolyte fuel cells due to their low cost and high activity towards the oxygen reduction reaction (ORR). Since Fe−N−C active sites are preferentially formed in the micropores of the carbon matrix, increasing the microporosity is highly appealing. In this work, carbon xerogels (CXG) were activated by physical and chemical methods to favor the formation of micropores, used as carbon matrices for Fe−N−C catalysts, and investigated for the ORR. The catalysts were characterized by solid‐state techniques to determine chemical composition and pore structure. Physical activation increased microporosity up to 2‐fold leading to catalysts with a larger density of active sites (more than twice iron and nitrogen uptake, pyridinic N and Nx−Fe). This entailed a higher ORR intrinsic activity determined in a 3‐electrode cell (80 mV better half‐wave potential). At the cathode of a fuel cell, the catalysts based on activated carbon materials showed 26 % lower power density ascribed to a more hydrophilic surface, causing a larger extent of flooding of the electrode that counterbalances the higher intrinsic activity. Interestingly, a more stable behavior was observed for the activated catalysts, with up to 2‐fold better relative power density retention after 20‐hour operation. Activated carbon xerogels were studied as matrix for Fe−N−C catalysts. The increased microporosity lead to catalysts with a larger density of active sites, achieving up to more than twice iron and nitrogen uptake, and consequently, a higher ORR intrinsic activity. Whereas, fuel cell power density is negatively affected by a more hydrophilic character, but stability enhances with activation.

Atomically dispersed Fe-N-C catalysts for the oxygen reduction reaction (ORR) have been synthesized with a template-free method using carbon xerogels (CXG) as a porous matrix. The porosity of the CXGs is easily tunable through slight variations in the synthesis procedure. In this work, CXGs are prepared by formaldehyde and resorcinol polymerization, modifying the pH during the process. Materials with a broad range of porous structures are obtained: from non-porous to micro-/meso-/macroporous materials. The porous properties of CXG have a direct effect on Fe-N-CXG activity against ORR in an acidic medium (0.5 M H2SO4). Macropores and wide mesopores are vital to favor the mass transport of reagents to the active sites available in the micropores, while narrower mesopores can generate additional tortuosity. The role of microporosity is investigated by comparing two Fe-N-C catalysts using the same CXG as the matrix but following a different Fe and N doping procedure. In one case, the carbonization of CXG occurs rapidly and simultaneously with Fe and N doping, whereas in the other case it proceeds slowly, under controlled conditions and before the doping process, resulting in the formation of more micropores and active sites and achieving higher activity in a three-electrode cell and a better durability during fuel cell measurements. This work proves the feasibility of the template-free method using CXG as a carbon matrix for Fe-N-C catalysts, with the novelty of the controlled porous properties of the carbon material and its effect on the catalytic activity of the Fe-N-C catalyst. Moreover, the results obtained highlight the importance of the carbon matrix’s porous structure in influencing the activity of Fe-N-C catalysts against ORR.