This paper presents part of a study that aimed to make more explicit the pragmatic theories that inform the design of professional development programs with an emphasis on the integration of digital technologies in the practices of mathematics teachers. The analysis carried out was based on a set of projects considered representative and implemented in four countries – Colombia, Italy, Mexico and Portugal. Based on this analysis, we identify relevant elements (e.g., similarities and differences, barriers and opportunities) and develop recommendations to be taken into account in the design of future professional development programs. In this process, we identified a set of aspects and sub-aspects, as well as several interconnections between them, which emerged in relation to five main themes and allowed us to reveal our pragmatic theories. Thus, this work provides a framework to support the design of future projects for the professional development of mathematics teachers regarding the use of digital technology.

Due to the innovative possibilities of digital technologies, the issue of increasing automation is once again on the agenda – and not only in the industry, but also in other branches and sectors of contemporary societies. Although public and scientific discussions about automation seem to raise relevant questions of the “old” debate, such as the replacement of human labor by introducing new technologies, the authors focus here on the new contextual quality of these questions. The debate should rethink the relationship between technology and work with regard to quantitative and qualitative changes in work. In this article, our example will be the introduction of automation in industry, which has been reflected in the widely recognized study by Frey and Osborne in 2013. They estimated the expected impacts of future computerization on US labor market outcomes as very high, specifically regarding the number of jobs at risk. Surprisingly, this study was the starting point of an intensive international debate on the impact of technologies on the future of work and the role of technological change in working environments. Thus, according to the authors, “old” questions remain important, but they should be reinterpreted for “new” societal demands and expectations of future models of work.

This chapter aims to make more explicit the grounded or ‘pragmatic theories’ that inform the design of mathematics teachers’ professional development (PD) to exploit technological affordances. It uses aspects of some representative projects that took place in four countries (Colombia, Italy, Mexico, and Portugal) to illustrate lessons learned (e.g., similarities and differences, barriers and opportunities) and provide important insights to inform future PD implementations. To do this, we have identified a set of aspects (and sub-aspects) that emerged in relation to five major themes and reveal our ‘pragmatic theories’ alongside a consideration of the interconnections between these aspects. Our contribution offers a methodological frame to support future PD designs for teachers of mathematics concerning digital technology uses.

In this short note we construct an extension of the Vagner-Preston representation for block-groups and show that its kernel is the largest congruence that separates regular elements.

The Cellulosome is an intricate macromolecular protein complex that centralizes the cellulolytic efforts of many anaerobic microorganisms through the promotion of enzyme synergy and protein stability. The assembly of numerous carbohydrate processing enzymes into a macromolecular multiprotein structure results from the interaction of enzyme-borne dockerin modules with repeated cohesin modules present in noncatalytic scaffold proteins, termed scaffoldins. Cohesin–dockerin (Coh-Doc) modules are typically classified into different types, depending on structural conformation and cellulosome role. Thus, type I Coh-Doc complexes are usually responsible for enzyme integration into the cellulosome, while type II Coh-Doc complexes tether the cellulosome to the bacterial wall. In contrast to other known cellulosomes, cohesin types from Bacteroides cellulosolvens, a cellulosome-producing bacterium capable of utilizing cellulose and cellobiose as carbon sources, are reversed for all scaffoldins, i.e., the type II cohesins are located on the enzyme-integrating primary scaffoldin, whereas the type I cohesins are located on the anchoring scaffoldins. It has been previously shown that type I B. cellulosolvens interactions possess a dual-binding mode that adds flexibility to scaffoldin assembly. Herein, we report the structural mechanism of enzyme recruitment into B. cellulosolvens cellulosome and the identification of the molecular determinants of its type II cohesin–dockerin interactions. The results indicate that, unlike other type II complexes, these possess a dual-binding mode of interaction, akin to type I complexes. Therefore, the plasticity of dual-binding mode interactions seems to play a pivotal role in the assembly of B. cellulosolvens cellulosome, which is consistent with its unmatched complexity and size.

Carbon fibre reinforced polymer (CFRP) composite systems are widely used to strengthen reinforced concrete (RC) structures through bonding strips/sheets on the concrete surface – externally bonded reinforcement (EBR) technique, or through strips/rods bonded inside slits in the concrete cover – near-surface mounted (NSM) technique. Although both techniques provide high strength increases, it is usually not possible to use the CFRPs’ full strength due to premature debonding, especially with EBR. This limitation can be overcome when using CREatE (continuous reinforcement embedded at ends) technique (developed by the last three authors), which consists of (i) bonding the central part of the CFRP strip (as in EBR), or the CFRP rod (as in NSM), and (ii) anchoring both ends of the strip/rod inside the concrete section, after a transition curve, enhancing its anchorage capacity. However, all these techniques are susceptible to fire, due to the polymeric nature of CFRP materials and epoxy adhesives. This paper presents the results of an experimental study regarding the fire behaviour of RC slab strips strengthened with EBR, NSM and CREatE techniques, in which the influence of applying different fire protection systems was investigated. The specimens were strengthened with those systems and simultaneously subjected to a service load and the ISO 834 fire curve. The following main results were obtained: (i) without fire protection, the CREatE technique presented the highest fire resistance due to the better anchorage of the CFRP; (ii) when protected, the NSM technique presented higher fire resistance compared to EBR and CREatE techniques; and (iii) “critical” temperatures were proposed for each technique, 1.0Tg, 2.5Tg, and 3.0Tg for EBR, NSM and CREatE techniques, respectively. © Fédération Internationale du Béton (fib) – International Federation for Structural Concrete.

Microstructured transparent conductive oxides (TCOs) have shown great potential as photonic electrodes in photovoltaic (PV) applications, providing both optical and electrical improvements in the solar cells’ performance due to: (1) strong light trapping effects that enhance broadband light absorption in PV material and (2) the reduced sheet resistance of the front illuminated contact. This work developed a method for the fabrication and optimization of wavelength-sized indium zinc oxide (IZO) microstructures, which were soft-patterned on flexible indium tin oxide (ITO)-coated poly(ethylene terephthalate) (PET) substrates via a simple, low-cost, versatile, and highly scalable colloidal lithography process. Using this method, the ITO-coated PET substrates patterned with IZO micro-meshes provided improved transparent electrodes endowed with strong light interaction effects—namely, a pronounced light scattering performance (diffuse transmittance up to  50%). In addition, the photonic-structured IZO mesh allowed a higher volume of TCO material in the electrode while maintaining the desired transparency, which led to a sheet resistance reduction (by  30%), thereby providing further electrical benefits due to the improvement of the contact conductance. The results reported herein pave the way for a new class of photonic transparent electrodes endowed with mechanical flexibility that offer strong potential not only as advanced front contacts for thin-film bendable solar cells but also for a much broader range of optoelectronic applications.

Ion beam analysis of fluorine has applications in research on teeth and bones, materials science, geochemistry and archaeometry. A novel PIGE (particle induced gamma-ray emission) standard free methodology for fluorine content determination for in-depth heterogeneous samples based on the excitation function of the 19F(p,p’$\gamma$)19F nuclear reaction is presented. New precise cross section measurements of this reaction in the proton energy range 2.1 to 4.1 MeV have been performed. In addition, the ERYA-Profiling code, a computer program specially developed for PIGE analysis of in-depth heterogeneous samples, employed this new excitation function in a case study where different fluorine simulated depth profiles probed the capability of insight into fluorine distributions in a given sample, showing the potential of PIGE analysis.

The SOUL, or heme-binding protein HBP/SOUL, family represents a group of evolutionary conserved putative heme-binding proteins that contains a number of members in animal, plant andbacterial species. The structures of the murine form of HEBP1, or p22HBP, and the human form of HEBP2, or SOUL, have been determined in 2006 and 2011 respectively. In this work we discuss the structures of HEBP1 and HEBP2 in light of new X-ray data for heme bound murine HEBP1. The interaction between tetrapyrroles and HEBP1, initially proven to be hydrophobic in nature, was thought to also involve electrostatic interactions between heme propionate groups and positively charged amino acid side chains. However, the new X-ray structure, and results from murine HEBP1 variants and human HEBP1, confirm the hydrophobic nature of the heme-HEBP1 interaction, resulting in Kd values in the low nanomolar range, and rules out any electrostatic stabilization. Results from NMR relaxation time measurements for human HEBP1 describe a rigid globular protein with no change in motional regime upon heme binding. X-ray structures deposited in the PDB for human HEBP2 are very similar to each other and to the new heme-bound murine HEBP1 X-ray structure (backbone rmsd ca. 1 {\AA}). Results from a HSQC spectrum centred on the histidine side chain N$δ$-proton region for HEBP2 confirm that HEBP2 does not bind heme via H42 as no chemical shift differences were observed upon heme addition for backbone NH and N$δ$ protons. A survey of the functions attributed to HEBP1 and HEBP2 over the last 20 years span a wide range of cellular pathways. Interestingly, many of them are specific to higher eukaryotes, particularly mammals and a potential link between heme release under oxidative stress and human HEBP1 is also examined using recent data. However, at the present moment, trying to relate function to the involvement of heme or tetrapyrrole binding, specifically, makes little sense with our current biological knowledge and can only be applied to HEBP1, as HEBP2 does not interact with heme. We suggest that it may not be justified to call this very small family of proteins, heme-binding proteins. The family may be more correctly called “the SOUL family of proteins related to cellular fate” as, even though only HEBP1 binds heme tightly, both proteins may be involved in cell survival and/or proliferation.