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El impacto de las fake news en la investigación en Ciencias Sociales. Revisión bibliográfica sistematizada
No full textLas noticias falsas o fake news vienen ocupando un papel protagonista a nivel político, social, mediático y también, científico. En este trabajo se desarrolla una revisión sistematizada de los estudios realizados hasta la fecha sobre las noticias falsas, partiendo de las principales bases de datos (Web of Science, Dialnet Plus) y con el fin de verificar qué temas han atraído la atención de la comunidad científica al respecto, qué técnicas de investigación se han utilizado en estos estudios, dónde se concentran geográficamente y qué campos quedan aún por cubrir en torno a este fenómeno. El estudio realizado refleja que aún queda camino por recorrer, en especial, en el ámbito iberoamericano que aparece menos representado dentro de la producción científica sobre las noticias falsasFake news has begun to play a major role at the political, social, media, and even scientific level. In this work, a systematic review of the studies carried out to date on fake news has been developed starting from the main databases (Web of Science, Dialnet Plus), with the aim of verifying which topics have attracted the attention of the scientific community in this regard, what research techniques have been used in these studies, where these are geographically concentrated, and what fields still need to be investigated regarding this phenomenon. This study shows that there is still a long way to go, especially in the Ibero-American sphere that appears quantitatively less represented in the context of scientific production on fake news
Diseño de tareas en el marco de la teoría antropológica de lo didáctico
No full textEn la Teoría Antropológica de lo Didáctico (TAD), el diseño de tareas se integra dentro de su metodología experimental planteada en términos de ingeniería didáctica. La implementación de nuevas organizaciones de enseñanza y aprendizaje, basadas en nuevas formas de concebir las actividades matemáticas escolares, se inscribe en una problemática epistemológica e institucional. En este artículo, presentamos una reflexión sobre los objetivos, los principios, la metodología y el alcance que atribuimos a este trabajo experimental. La reflexión se complementa con la descripción de tres casos, que sirven para ejemplificar cómo estos objetivos, principios y metodología han sido implementados en procesos didácticos concretos. Concluimos con una reflexión sobre la necesaria dialéctica y articulación entre investigación, diseño y prácticas de aula a fin de profundizar en el análisis de la ecología de estas propuestas, es decir, de las condiciones que permiten que ciertas tareas puedan vivir en las instituciones docentes, así como las restricciones que impiden su desarrollo como actividades normalizadas en el aula, desde una visión no normativa de la investigación didácticaIn the Anthropological Theory of the Didactic (ATD), task design is integrated into its experimental methodology in terms of didactic engineering. The implementation of new teaching and learning organizations, based on new ways of conceiving school mathematical activities, is an integral component of the ATD epistemological and institutional analyses. In this article, we reflect on the objectives, principles, methodology and scope that we attribute to this experimental work. Three cases complement this reflection, to exemplify how these objectives, principles and methodology have been implemented in concrete didactic processes. We conclude with a reflection about the necessary dialectic between research, design and teaching practices, with the aim of deepening into the analysis of the ecology of our proposals, that is, the conditions that enable certain activities to exist in school institutions, as well as the constraints that hinder their development as normalised classroom activities, from a non-normative perspective of didactic researchNa Teoria Antropológica do Didático (TAD), o desenho de tarefas integra-se dentro da sua metodologia experimental formulada em termos de engenharia didática. A implementação de novas organizações de ensino e aprendizagem, baseadas em novas formas de conceber as atividades matemáticas escolares, faz parte de uma problemática epistemológica e institucional. Neste artigo, apresentamos uma reflexão sobre os objetivos, os princípios, a metodologia e o alcance que atribuímos a este trabalho experimental. Esta reflexão é complementada com a descrição de três casos, que servem para exemplificar como estes objetivos, princípios e metodologia foram implementados em processos didáticos concretos. Concluímos com uma reflexão sobre a necessária dialética e articulação entre investigação, desenho e práticas de aula, a fim de aprofundar a análise da ecologia destas propostas, ou seja, as condições que permitem que certas tarefas possam viver nas instituições de ensino, assim como as restrições que impedem o seu desenvolvimento como atividades normalizadas em sala de aula, a partir de uma visão não normativa da investigação didáticaDans la Théorie Anthropologique du Didactique (TAD), la conception de tâches d'enseignement est intégrée dans sa méthodologie expérimentale en termes d'ingénierie didactique. La mise en place de nouvelles organisations didactiques, basées sur de nouvelles façons de concevoir les activités mathématiques scolaires, s'inscrit dans une problématique épistémologique et institutionnelle. Dans cet article, nous présentons une réflexion sur les objectifs, principes, méthodologie et portée que nous attribuons à ce travail expérimental. Cette réflexion est complétée par la description de trois cas qui illustrent comment ces objectifs, principes et méthodes ont été mis en oeuvre dans des processus didactiques concrets. Nous concluons par une réflexion sur la dialectique et l'articulation nécessaires entre la recherche, le design et les pratiques en classe pour approfondir l'analyse de l'écologie des nouvelles organisations didactiques, c'est-à-dire des conditions qui permettent à certaines activités de vivre dans les institutions scolaires, ainsi que des contraintes qui empêchent leur développement comme activités normalisées en classe, dans une perspective non-normative de la recherche en didactiqu
Color tunable pressure sensors based on polymer nanostructured membranes for optofluidic applications
No full textWe demonstrate an integrated optical pressure sensing platform for multiplexed optofluidics applications. The sensing platform consists in an array of elastomeric on-side nanostructured membranes -effectively 2D photonic crystal- which present colour shifts in response to mechanical stress that alter their nanostructure characteristical dimensions, pitch or orientation. The photonic membranes are prepared by a simple and cost-effective method based on the infiltration of a 2D colloidal photonic crystal (CPC) with PDMS and their integration with a microfluidic system. We explore the changes in the white light diffraction produced by the nanostructured membranes when varying the pneumatic pressure in the microfluidics channels as a way to achieve a power-free array of pressure sensors that change their reflective colour depending on the bending produced on each sensor. The structural characterization of these membranes was performed by SEM, while the optical properties and the pressure-colour relation were evaluated via UV-Vis reflection spectrometry. Maximum sensitivities of 0.17 kPa is obtained when measuring at Littrow configuration (θ = −θ ), and close to the border of the membranes. The reflected colour change with pressure is as well monitorized by using a smartphone camera
Enhanced thermoelectric properties of lightly Nb doped SrTiO3 thin films
No full textNovel thermoelectric materials developed for operation at room temperature must have similar or better performance along with being as ecofriendly as those commercially used, e.g., BiTe, in terms of their toxicity and cost. In this work, we present an in-depth study of the thermoelectric properties of epitaxial Nb-doped strontium titanate (SrTiNbO) thin films as a function of (i) doping concentration, (ii) film thickness and (iii) substrate type. The excellent crystal quality was confirmed by high resolution transmission electron microscopy and X-ray diffraction analysis. The thermoelectric properties were measured by the three-omega method (thermal conductivity) and van der Pauw method (electrical resistivity), complemented by Seebeck coefficient measurements. A maximum power factor of 8.9 × 10 W m K and a thermoelectric figure of merit of 0.49 were measured at room temperature in 50 nm-thick films grown on lanthanum strontium aluminate. The mechanisms behind this high figure of merit are discussed in terms of a possible two-dimensional electron gas, increase of the effective mass of the electrons, electron filtering and change in strain due to different substrates. The overall enhancement of the thermoelectric properties suggests that SrTiNbO is a very promising n-type candidate for room- to high-temperature applications
Australian vegetated coastal ecosystems as global hotspots for climate change mitigation
No full textUnidad de excelencia María de Maeztu MdM-2015-0552Policies aiming to preserve vegetated coastal ecosystems (VCE; tidal marshes, mangroves and seagrasses) to mitigate greenhouse gas emissions require national assessments of blue carbon resources. Here, we present organic carbon (C) storage in VCE across Australian climate regions and estimate potential annual CO emission benefits of VCE conservation and restoration. Australia contributes 5-11% of the C stored in VCE globally (70-185 Tg C in aboveground biomass, and 1,055-1,540 Tg C in the upper 1 m of soils). Potential CO emissions from current VCE losses are estimated at 2.1-3.1 Tg CO-e yr, increasing annual CO emissions from land use change in Australia by 12-21%. This assessment, the most comprehensive for any nation to-date, demonstrates the potential of conservation and restoration of VCE to underpin national policy development for reducing greenhouse gas emissions
Efficient bioactive oligonucleotide-protein conjugation for cell-targeted cancer therapy
No full textOligonucleotide-protein conjugates have important applications in biomedicine. Simple and efficient methods are described for the preparation of these conjugates. Specifically, we describe a new method in which a bifunctional linker is attached to thiol-oligonucleotide to generate a reactive intermediate that is used to link to the protein. Having similar conjugation efficacy compared with the classical method in which the bifunctional linker is attached first to the protein, this new approach produces significantly more active conjugates with higher batch to batch reproducibility. In a second approach, direct conjugation is proposed using oligonucleotides carrying carboxyl groups. These methodologies have been applied to prepare nanoconjugates of an engineered nanoparticle protein carrying a T22 peptide with affinity for the CXCR4 chemokine receptor and oligomers of the antiproliferative nucleotide 2'-deoxy-5-fluorouridine in a very efficient way. The protocols have potential uses for the functionalization of proteins, amino-containing polymers or amino-lipids in order to produce complex therapeutic nucleic acid delivery system
Cr2Te3 Thin Films for Integration in Magnetic Topological Insulator Heterostructures
No full textChromium telluride compounds are promising ferromagnets for proximity coupling to magnetic topological insulators (MTIs) of the Cr-doped (Bi,Sb)(Se,Te) class of materials as they share the same elements, thus simplifying thin film growth, as well as due to their compatible crystal structure. Recently, it has been demonstrated that high quality (001)-oriented CrTe thin films with perpendicular magnetic anisotropy can be grown on c-plane sapphire substrate. Here, we present a magnetic and soft x-ray absorption spectroscopy study of the chemical and magnetic properties of CrTe thin films. X-ray magnetic circular dichroism (XMCD) measured at the Cr L edges gives information about the local electronic and magnetic structure of the Cr ions. We further demonstrate the overgrowth of CrTe (001) thin films by high-quality Cr-doped SbTe films. The magnetic properties of the layers have been characterized and our results provide a starting point for refining the physical models of the complex magnetic ordering in CrTe thin films, and their integration into advanced MTI heterostructures for quantum device applications
Innovation, Spatial Loyalty, and ICTs as Locational Determinants of Rural Development in the Catalan Pyrenees
No full textInnovació, lleialtat espacial i TICs com a determinants de la localització en el desenvolupament rural del Pirineu català. Les tecnologies de la informació i la comunicació (TIC) obren noves possibilitats de desenvolupament en zones ruralsi de muntanya. S'analitza les TIC com a factor d'atracció de negoci; i que facilita una dispersió de l'activitat econòmica, generalment concentrada en les àrees metropolitanes. Aquestes zones rurals i de muntanya s'han beneficiat de la incorporació creixent de les TIC a les empreses, atès que aquest procés promou estratègies de desenvolupament viables, portant els territoris locals als mercats globals i viceversa. La competitivitat i el valor afegit de les empreses de desenvolupament local s'incorporen al producte amb la valorització d'aquests factors d'identitat locals. Altres factors de localització competitius d'aquestes zones són uns costos de localització menor així com la lleialtat espacial entre les empreses del clúster. D'altra banda, pot haver-hi una escassetat de treballadors qualificats que difícilment estaran disponibles a priori en aquestes àrees específiques. Dèficit que es pot compensar per la petita dimensió de les empreses ubicades en aquestes zones. és pretén explicar alguns casos específics d'empreses del Pirineu català, on hi realitzen algunes parts del procés productiu amb més valor afegit (disseny, organització, etc.) mentre que la fabricació es troba en altres països amb salaris més baixos. També s'analitzen algunes activitats i serveis que generen explotacions agràries i territoris rurals intel·ligents. Llavors, les TIC són importants per al nivell educatiu i informatiu de la població i per a la instal·lació de noves empreses a les zones rurals i de muntanya.Information and communication technologies (ICTs) open up new possibilities for development in rural and mountain areas. ICTs a analysed as a factor attracting business and enabling a dispersion of economic activity that is usually concentrated in metropolitan areas. Rural and mountain areas have benefited from the increasing incorporation of ICT in companies because development strategies are now made viable, thus bringing local territories into global markets and vice versa. Competitiveness and the added value of local development companies are incorporated into the product through the value given to local identity factors. Other competitive localisation factors of these zones are lower localisation costs and spatial loyalty among companies in the cluster. On the other hand, there may be an a priori shortage of available skilled workers in these particular areas but this deficit could be balanced out by the small size of companies established in these zones. This paper describes several case studies of specific companies in the Catalan Pyrenees where parts of the productive process with the highest added value - like design, organisation, etc - are carried out, while manufacturing occurs in other countries. It also analyses activities and services offered by smart farms and in smart rural areas. ICTs are important for the educational and informative levels of the population and also for the establishment of new companies and services in rural and mountain areas
An alternative to market-oriented energy models : Nexus patterns across hierarchical levels
No full textUnidad de excelencia María de Maeztu MdM-2015-0552From a biophysical perspective, energy is central to the behaviour of social-ecological systems. Its ubiquity means that energy is entangled with nexus elements, including water, land, emissions and labour. At the science-policy interface, large market-oriented energy models dominate as the tool to inform decision-making. The outputs of these models are used to shape policies, but strongly depend on sets of assumptions that are not available for deliberation and gloss over uncertainties. Taking an approach from complexity, we propose an alternative to market-oriented energy models, describing the behaviour of energy systems in relation to patterns of nexus elements across hierarchical levels. Three characteristics are central to the approach: (i) the distinction of the model's building blocks into functional and structural elements; (ii) their hierarchical organisation and (iii) the description of nexus patterns at each level, through the tool of the processor. To illustrate the model, it is applied to Catalonia's energy sector, linking production and consumption patterns. The framework may help inform stakeholder deliberation on pressing energy and nexus issues
Biochar amendment improves degraded pasturelands in Brazil : environmental and cost-benefit analysis
No full textUnidad de excelencia María de Maeztu MdM-2015-0552Most deforested lands in Brazil are occupied by low-productivity cattle ranching. Brazil is the second biggest meat producer worldwide and is projected to increase its agricultural output more than any other country. Biochar has been shown to improve soil properties and agricultural productivity when added to degraded soils, but these effects are context-dependent. The impact of biochar, fertilizer and inoculant on the productivity of forage grasses in Brazil (Brachiaria spp. and Panicum spp.) was investigated from environmental and socio-economic perspectives. We showed a 27% average increase in Brachiaria production over two years but no significant effects of amendment on Panicum yield. Biochar addition also increased the contents of macronutrients, soil pH and CEC. Each hectare amended with biochar saved 91 tonnes of COeq through land sparing effect, 13 tonnes of COeq sequestered in the soil, equating to