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International audience ; Graphene is the enabling material of the 21st century andthere are high expectations for its potential applications. Aclear and consistent system describing the various derivativesof graphene promotes a precise vocabulary for the family ofgraphene-based materials. This will be a prerequisite, forexample, to understand structure–activity relationships in thecontext of human health and safety and to avoid generalizationsabout the capabilities and limitations of graphenebasedmaterials. Within the European Union's GRAPHENEFlagship project, three physical-chemical descriptors specificfor graphene were defined to assist in the classification ofgraphene-based materials.

The intended new context-based curriculum for four science subjects (AS-MaT1, biology, chemistry, and physics) in senior general secondary education and pre-university education has been the subject of numerous research and teacher professionalisation efforts in the Netherlands for the last seven years. Following international forerunners, the context-based approach was chosen to counter falling interest in future education in science among students. The governmentally instituted innovation committees were committed to have input from teachers as well as university experts as to what the various curricula should contain. In the discussions on context-based education the focus has mainly been placed on the details on what a context-based approach should entail for each science subject. The committees were prepared to test the new curriculum in years 10-12 in secondary education, including the national exams, for which they needed new context-based cur- riculum materials. These context-based curriculum modules were made by teams of teachers and academic experts, although the actual line-up of the teams varied, from one teacher working alone and testing the material in the own classroom, to several teachers and experts working together with the final product being edited by a professional editor. The teachers working in these design teams for context-based curriculum material are expected to have learned more about the context-based approach than their peers without this experience. The learning of teachers in design teams for context-based materials was the topic of this thesis. The aim was to construct an optimal professional development programme for science teachers based on the experiences of these designers. First a definition of context-based education that would do justice to the national and international literature needed to be constructed. Then a translation from this definition to the teaching practice was made, by defining five teaching competences important for teaching context-based education. These competences were context handling, regulation, emphasis, design, and school innovation. The general research question in this thesis was: How does the participation of teachers in context-based design teams (ASMaT, biology, chemistry, and physics) contribute to their professional development towards contextbased teaching, and which factors concerning the design experience hinder or facilitate this development? A composite instrument able to measure the five context-based teaching competences was constructed and tested in a pilot study. Quantitative parts of the composite instrument were evaluated further in two national studies. The composite instrument was found to be valid and reliable for measuring the context-based competence of teachers. The validated instrument was used in a larger study amongst teachers who designed curriculum materials for the context-based innovation and teachers who were not involved in designing. Designers were found to have acquired more context-based competence than non-designers. An influence of the material used in class on context-based competence was also dis- covered. Using a combination of context-based curriculum modules and a standard textbook in class resulted in more context-based competence. The designers were interviewed on their design experience. The answers were analysed to find that some kind of structure should be used when de- signing curriculum materials. This structure could be a learning continuity pathway, a project planning and task division, or rules of thumb to ensure the designed curriculum material contained everything it should. The context-based teaching competence of the designers was also correlated with characteristics of their design experience. Influencing factors were participants in the team, time spent on designing materials, and use of context-based materials in the own class. A professional development programme was designed and executed with six teachers using these factors and factors identified from literature on teacher professional development. The programme was successful in changing teachers context-based competences. The general conclusions include the confirmation of the five teaching competences in demand in context-based education as well as suggestions for additions to these competences. As stated above, not only has designing curriculum materials been found to influence context-based teaching competency, but also the use of a combination of standard textbook with context-based curriculum modules has a positive influence. For a professional development programme success factors have been identified, both general and specific to context-based education. These findings can be useful to the teaching practice, textbook publishers, institutions for teacher professional development and teacher training.

Two-dimensional (2D) materials exhibit a number of improved mechanical, optical, and electronic properties compared to their bulk counterparts. The absence of dangling bonds in the cleaved surfaces of these materials allows combining different 2D materials into van der Waals heterostructures to fabricate p-n junctions, photodetectors, and 2D-2D ohmic contacts that show unexpected performances. These intriguing results are regularly summarized in comprehensive reviews. A strategy to tailor their properties even further and to observe novel quantum phenomena consists in the fabrication of superlattices whose unit cell is formed either by two dissimilar 2D materials or by a 2D material subjected to a periodic perturbation, each component contributing with different characteristics. Furthermore, in a 2D material-based superlattice, the interlayer interaction between the layers mediated by van der Waals forces constitutes a key parameter to tune the global properties of the superlattice. The above-mentioned factors reflect the potential to devise countless combinations of van der Waals 2D material-based superlattices. In the present feature article, we explain in detail the state-of-the-art of 2D material-based superlattices and describe the different methods to fabricate them, classified as vertical stacking, intercalation with atoms or molecules, moiré patterning, strain engineering and lithographic design. We also aim to highlight some of the specific applications of each type of superlattices. ; This project has received funding from the European Research Council (ERC) under European Union's Horizon 2020 research and innovation programme (grant agreement no 755655, ERC-StG 2017 project 2D-TOPSENSE). R. F. acknowledges the support from the Spanish Ministry of Economy, Industry and Competitiveness through a Juan de la Cierva-formación fellowship 2017 FJCI-2017-32919. We acknowledge support of the publication fee by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI).

Ionic liquids (ILs) have been extensively explored and implemented in different areas, ranging from sensors and actuators to the biomedical field. The increasing attention devoted to ILs centers on their unique properties and possible combination of different cations and anions, allowing the development of materials with specific functionalities and requirements for applications. Particularly for biomedical applications, ILs have been used for biomaterials preparation, improving dissolution and processability, and have been combined with natural and synthetic polymer matrixes to develop IL-polymer hybrid materials to be employed in different fields of the biomedical area. This review focus on recent advances concerning the role of ILs in the development of biomaterials and their combination with natural and synthetic polymers for different biomedical areas, including drug delivery, cancer therapy, tissue engineering, antimicrobial and antifungal agents, and biosensing. ; The authors thank the FCT (Fundacao para a Ciencia e Tecnologia) for financial support under the framework of the Strategic Funding UID/FIS/04650/2019 and pro-jects PTDC/BTM-MAT/28237/2017, PTDC/EMD-EMD/28159/2017, and PTDC/FIS-MAC/28157/2017. Funds provided by FCT in the framework of EuroNano-Med 2016 call, Project LungChek ENMed/0049/2016 are also gratefully acknowledged. D.M.C., L.C.F., R.M.M., and M.M.F. also thank the FCT for the grants SFRH/BPD/121526/2016, SFRH/BD/145345/2019, and FRH/BD/148655/2019, SFRH/BPD/121464/2016, respectively and CR thanks the FCT for the contract under the Stimulus of Scientific Employment (2020.04163.CEECIND). S.L.M. and J.R. acknowledge the funding support from the Spanish State Research Agency (AEI) through the project PID2019-106099RB-C43/AEI/10.13039/501100011033 and from the Basque Government Industry Department under the ELKARTEK program. ...

9 14 1 ; OJS ; [EN] In recent years, light-transmitting cement-based materials (LTCM) have become important in the construction of green buildings because these reduce energy consumption for lighting. LTCMs were prepared by adding polymeric optical fibers (POFs) in a high strength self-compacting mortar (SCM). SCM was formulated from Portland cement, fine sand and water reducing admixture following the EFNARC criteria. LTCMs with a constant fiber content (5%) and three fiber diameter (0.75, 1 and 1.5 mm) were prepared by casting fresh SCM into a formwork designed ad hoc to keep the fibers fixed and aligned. Light transmitting performance of LTCM was tested by optical power measures. The effects of fiber diameter and distance between sample and detector on the optical power were evaluated. The compressive strength of hardened SCM reached a value of 69 MPa at an age of 28 days, while the LTCMs maintained sufficient strength for structural purposes. LTCMs are suitable to produce precast blocks and wall panels for application in building facades, signage and decorative art. This work was supported by the Agencia Nacional de Promoción Científica y Tecnológica (ANPCyT) under Grant PICT 2016 0445; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) Argentina. Special thanks to Ing. Juan Belmonte and Lic Andres Torres for their assistance in mechanical tests. Robles, A.; Arenas, GF.; Stefani, PM. (2020). Light transmitting cement-based material (LTCM) as a green material for building. Journal of Applied Research in Technology & Engineering. 1(1):9-14. https://doi.org/10.4995/jarte.2020.13832

This is the peer reviewed version of the following article: Bernardos, A., Piacenza, E., Sancenón, F., Hamidi, M., Maleki, A., Turner, R. J., Martínez-Máñez, R., Mesoporous Silica-Based Materials with Bactericidal Properties. Small 2019, 15, 1900669. https://doi.org/10.1002/smll.201900669 , which has been published in final form at https://doi.org/10.1002/smll.201900669. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. ; [EN] Bacterial infections are the main cause of chronic infections and even mortality. In fact, due to extensive use of antibiotics and, then, emergence of antibiotic resistance, treatment of such infections by conventional antibiotics has become a major concern worldwide. One of the promising strategies to treat infection diseases is the use of nanomaterials. Among them, mesoporous silica materials (MSMs) have attracted burgeoning attention due to high surface area, tunable pore/particle size, and easy surface functionalization. This review discusses how one can exploit capacities of MSMs to design and fabricate multifunctional/controllable drug delivery systems (DDSs) to combat bacterial infections. At first, the emergency of bacterial and biofilm resistance toward conventional antimicrobials is described and then how nanoparticles exert their toxic effects upon pathogenic cells is discussed. Next, the main aspects of MSMs (e.g., physicochemical properties, multifunctionality, and biosafety) which one should consider in the design of MSM-based DDSs against bacterial infections are introduced. Finally, a comprehensive analysis of all the papers published dealing with the use of MSMs for delivery of antibacterial chemicals (antimicrobial agents functionalized/adsorbed on mesoporous silica (MS), MS-loaded with antimicrobial agents, gated MS-loaded with antimicrobial agents, MS with metal-based nanoparticles, and MS-loaded with metal ions) is provided. ; The authors thank the Spanish Government (projects MAT2015-64139-C4-1-R and ...

The production of liquid biofuels to blend with gasoline is of worldwide importance to secure the energy supply while reducing the use of fossil fuels, supporting the development of rural technology with knowledge‐based jobs and mitigating greenhouse gas emissions. Today, engineering for plant construction is accessible and new processes using agricultural residues and municipal solid wastes have reached a good degree of maturity and high conversion yields (almost 90% of polysaccharides are converted into monosaccharides ready for fermentation). For the complete success of the 2G technology, it is still necessary to overcome a number of limitations that prevent a first‐of‐a‐kind plant from operating at nominal capacity. We also claim that the triumph of 2G technology requires the development of favourable logistics to guarantee biomass supply and make all actors (farmers, investors, industrial entrepreneurs, government, others) aware that success relies on agreement advances. The growth of ethanol production for 2020 seems to be secured with a number of 2G plants, but public/private investments are still necessary to enable 2G technology to move on ahead from its very early stages to a more mature consolidated technology.