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There is a need worldwide to develop materials for advanced power plants with steam temperatures of 700°C and above that will achieve long-term creep-rupture strength and low CO2 emissions. The creep resistance of actual 9-12Cr steels is not enough to fulfil the engineering requirements above 600°C. In this paper, the authors report their advances in the improvement of creep properties of this type of steels by the microstructural optimization through nano-precipitation using two methodologies. 1) Applying a high temperature austenitization cycle followed by an ausforming step (thermomechanical treatment, TMT) to G91 steel, to increase the martensite dislocation density and, thus, the number density of MX precipitates (M = V,Nb; X = C,N) but at the expense of deteriorating the ductility. 2) Compositional adjustments, guided by computational thermodynamics, combined with a conventional heat treatment (no TMT), to design novel steels with a good ductility while still possessing a high number density of MX precipitates, similar to the one obtained after the TMT in G91. The microstructures have been characterized by optical, scanning and transmission electron microscopy, EBSD and atom probe tomography. The creep behaviour at 700°C has been evaluated under a load of 200 N using small punch creep tests.

In order to increase scientific competence within the general population, it is important that teachers and educators have a realistic image of science and scientists, leaving aside superstitions and pseudoscientific claims that could be transmitted to their students. A starting point in this strategy is to make a good diagnosis of the future teachers' perceptions of science and technology. To this end, in this paper, we present a survey conducted with 383 Spanish university students, training to become schoolteachers. We focused on their interest in science and technology and their degree of trust in false beliefs and pseudoscience. The results are analysed and compared with those of a group of similar age and educational background that have answered a general population survey. It was found that, although the interest in science and technology and the trust in scientists is higher in pre-service teachers than in the general population, their level of belief in pseudoscientific issues is comparable, or even higher in some cases to those of the general population. The results show that these false beliefs are independent of the interest that future teachers show in science and technology. The presence of such beliefs among pre-service teachers should be a source of reflection, since these may be part of the hidden curriculum that they will transmit to their students.

Background: Diarrhoea remains one of the leading causes of childhood mortality globally. Recent epidemiological studies conducted in low-middle income countries (LMICs) identified Shigella spp. as the first and second most predominant agent of dysentery and moderate diarrhoea, respectively. Antimicrobial therapy is often necessary for Shigella infections; however, we are reaching a crisis point with efficacious antimicrobials. The rapid emergence of resistance against existing antimicrobials in Shigella spp. poses a serious global health problem. Methods: Aiming to identify alternative antimicrobial chemicals with activity against antimicrobial resistant Shigella, we initiated a collaborative academia-industry drug discovery project, applying high-throughput phenotypic screening across broad chemical diversity and followed a lead compound through in vitro and in vivo characterisation. Results: We identified several known antimicrobial compound classes with antibacterial activity against Shigella. These compounds included the oral carbapenem Tebipenem, which was found to be highly potent against broadly susceptible Shigella and contemporary MDR variants for which we perform detailed pre-clinical testing. Additional in vitro screening demonstrated that Tebipenem had activity against a wide range of other non-Shigella enteric bacteria. Cognisant of the risk for the development of resistance against monotherapy, we identified synergistic behaviour of two different drug combinations incorporating Tebipenem. We found the orally bioavailable prodrug (Tebipenem pivoxil) had ideal pharmacokinetic properties for treating enteric pathogens and was effective in clearing the gut of infecting organisms when administered to Shigella-infected mice and gnotobiotic piglets. Conclusions: Our data highlight the emerging antimicrobial resistance crisis and shows that Tebipenem pivoxil (licenced for paediatric respiratory tract infections in Japan) should be accelerated into human trials and could be repurposed as an effective treatment for severe diarrhoea caused by MDR Shigella and other enteric pathogens in LMICs. Funding: Tres Cantos Open Lab Foundation (projects TC239 and TC246), the Bill and Melinda Gates Foundation (grant OPP1172483) and Wellcome (215515/Z/19/Z).

The emergence of drug-resistant strains of Mycobacterium tuberculosis (Mtb) ensures that drug discovery efforts remain at the forefront of TB research. There are multiple different experimental approaches that can be employed in the discovery of anti-TB agents. Notably, inhibitors of MmpL3 are numerous and structurally diverse in Mtb and have been discovered through the generation of spontaneous resistant mutants and subsequent whole genome sequencing studies. However, this approach is not always reliable and can lead to incorrect target assignment and requires orthogonal confirmatory approaches. In fact, many of these inhibitors have also been shown to act as multi-target agents, with secondary targets in Mtb, as well as in other non-MmpL3-containing pathogens. Herein, we have investigated further the cellular targets of the MmpL3-inhibitor BM212 and a number of BM212 analogues. To determine the alternative targets of BM212, which may have been masked by MmpL3 mutations, we have applied a combination of chemo-proteomic profiling using bead-immobilised BM212 derivatives and protein extracts, along with whole-cell and biochemical assays. The study identified EthR2 (Rv0078) as a protein that binds BM212 analogues. We further demonstrated binding of BM212 to EthR2 through an in vitro tryptophan fluorescence assay, which showed significant quenching of tryptophan fluorescence upon addition of BM212. Our studies have demonstrated the value of revisiting drugs with ambiguous targets, such as MmpL3, in an attempt to find alternative targets and the study of off-target effects to understand more precisely target engagement of new hits emerging from drug screening campaigns.

Introduction: This article explores the scientific ideas and alternative conceptions that pre-service teachers have regarding animal classification and spiders in particular. Method: The study involved 40 pre-service teachers of elementary education in Spain and the data was collected by means of questionnaires, descriptions and drawings. The students completed all the tests proposed in this research at the beginning of class sessions. Results: We found several misconceptions, some of them consistent with children's interpretations. The results show that the majority had great difficulty distinguishing between vertebrates and invertebrates, and although all the participants said they were familiar with spiders the results indicate that the majority have scarce knowledge of them. Discussion and conclusions: These prospective teachers may begin teaching at school without really having a good understanding of living things. These results should serve to reformulate the current development of the curriculum on invertebrates in Spain and foster practical instruction about living organisms for future teachers. (Contains 5 tables, 12 figures and 6 online resources.)

Se describen y analizan los resultados de un estudio sobre las plantas en los libros de texto de Conocimiento del Medio de tercer y cuarto curso de educación primaria (escolares de 8-10 años). Concretamente: ¿qué deben conocer los niños sobre las plantas?; ¿qué características generales siguen los libros en el planteamiento del tema?; ¿cómo es el tratamiento de los contenidos de conceptos, procedimientos y actitudes sobre plantas?; y ¿cuáles son los objetivos de las actividades de aprendizaje que presentan? Los resultados mostraron que las plantas son muy importantes en la educación primaria; sin embargo, los libros examinados no enseñan a los escolares a analizar la realidad vegetal, y muy poco a aplicar los conocimientos en su vida cotidiana; y presentan algunos conceptos confusos (por ej., nutrición, alimentación, respiración y reproducción sexual). Este estudio proporciona indicadores que pueden ayudar a los docentes para analizar y discutir la adecuación de los libros de texto al currículum vigente.

Este artículo surgió a partir del interés de las autoras en incorporar en las asignaturas de la materia de Psicología de los grados de Magisterio y Educación Social las aportaciones que se están realizando desde la Psicología Positiva y la Educación Positiva. A lo largo del texto las autoras justifican, en primer lugar, la importancia de incorporar estas aportaciones, en segundo lugar exponen las variables que favorecen la optimización del desarrollo en los niños, niñas y jóvenes, basándose en las propuestas de varias instituciones internacionales. Por último, dado que sería imposible reflexionar sobre todas las variables descritas, se reflexiona sobre dos de ellas: la necesidad de establecer con el educando vínculos sociales seguros y confiados y la necesidad de proporcionarle situaciones en las que pueda experimentar éxito con el objetivo de poner de relieve la importancia de que los educadores/as las tengan presentes en su trabajo diario.

An efficient synthesis of ent-halimanolide 2 (15,16-epoxy-12-oxo-ent-halima- 5(10),13(16),14-trien-18,2β-olide), from ent-halimic acid has been achieved, corroborating the structure of the natural compound and establishing its absolute configuration.

The rearrangement under oxidative conditions of 3-(benzyloxy)-tetrahydro- 2,6,6-trimethyl-2H-pyran-2-carbaldehydes to afford a chiral protected tetrahydrofuran lactol is described.

For the first time ent-labdanes have been synthetised starting from ent-halimic acid, following a route that is the reverse of the biosynthetic one leading to the former compounds.

We report the asymmetric synthesis of di-3-pentyl (3S,αS,7E)-3-N-benzyl-N- α-methylbenzylamino-dec-7-enedioate (9), which contains the correct functionalization to produce δ-amino acid derivatives to be used as monomers for Peptide Nucleic Acid (PNA) formation With this aim, thymine-pentanoic acid 15 and some of its ester derivatives were obtained, their reactivity was studied and the noteworthy ethyl ester 12 was quantitatively produced by transesterification of methyl ester 11, thus paving the way for the synthesis of the thymine-containing amino ester IV, which has been designed as a building block for a Nucleic-Acid analog with a chiral, flexible peptide backbone

Incubation of sclareol with Rhizopus stolonifer affords in high yield a mixture of triols with 18-hydroxy-sclareol as the main component.

A method to synthesize chiral 2,3,4-trisusbtituted tetrahydrothiophenes in both enantiomerically pure forms starting from 1-hydroxymethyl-4-phenylsulfonylbutadiene is described.

The asymmetric synthesis of the orthogonally funtionalised compounds tert-butyl 2-N-benzyl-N-α-methylbenzylamino-5-methoxycarbonylmethylcyclopentane- 1-carboxylate and methyl 2-N-benzyl-N-α-methylbenzylamino-5–carboxymethylcyclo- pentane-1-carboxylate by a domino reaction of tert-butyl methyl (E,E)-octa-2,6- diendioate with lithium N-α-methylbenzyl-N-benzylamide initiated by a Michael addition, subsequent 5-exo-trig intramolecular cyclisation and posterior selective hydrolysis with trifluoroacetic acid is reported.

A new route for the degradation of the saturated side chain of dihydrozamoranic acid has been devised, giving an advanced intermediate, compound 14, useful for the synthesis of insect antifeedants such as warburganal and polygodial.

The goal of this paper is to analyse the effect of adding Al on the non-steady pearlite growth occurring in a Fe–C–Mn system. The results are discussed in terms of the partitioning of elements across the austenite/ferrite and austenite/cementite interfaces, and the modification of the pearlite driving force related to the change in carbon activity in austenite.

El catálogo incluye las cuatro especies de Anyphaenidae (Araneae) conocidas en la Península Ibérica y Baleares. Para cada especie se recogen, ordenadas por provincias, todas las citas bibliográficas y se incluyen nuevas localidades correspondientes al material de la colección del Museo Nacional de Ciencias Naturales de Madrid, así como ejemplares procedentes de la colección de la autora, que amplían considerablemente el área de distribución conocida para cada una de ellas. Se da el atlas provisional de distribución de las especies de Anyphaenidae para el territorio de estudio sobre mapas de cuadrícula U.T.M. de 50 km de lado. Y se aportan, además, datos sobre su hábitat y ciclos de vida.

En este artículo se da el listado de las 38 especies de Philodromidae (Araneae) conocidas en la Península Ibérica y Baleares. La lista ordenada alfabéticamente, se presenta indicando las localidades por provincias y referencias bibliográficas donde se ha citado cada especie. Se incluye el material existente en la colección del Museo Nacional de Ciencias Naturales de Madrid, así como ejemplares de Philodromidae de otras procedencias. Se da el atlas provisional de distribución de las especies de Philodromidae para España peninsular e islas Baleares, y para Portugal y Andorra. La distribución de cada especie se indica sobre mapas de cuadrícula U.T.M. de 50 km de lado. Y se aportan además datos sobre su hábitat y ciclos de vida.

RESUMEN: En este trabajo ponemos de manifiesto la importancia que para la formación inicial de los maestros tiene incluir en sus curricula contenidos de Historia de la Ciencia. Nosotros proponemos incluir, en los programas de las asignaturas de Didáctica de Ciencias Experimentales de todas las especialidades de Magisterio, un tema teóricopráctico que trate algunas de las grandes controversias que a lo largo de los siglos han marcado el pensamiento científico, agrupándolas en tres apartados: el método de hacer Ciencia, la naturaleza de los seres vivos y la constitución del Universo.ABSTRACT: In this paper we try to show the great importance attached to the fact of including contents concerning History of Science in initial teacher education. We propose to include under the subjects related to Didactics of Experimental Sciences (whatever the speciality branch of teachers education) some of the most controversial topics which have been historical milestones in scientific thought. It will be possible to gather them into the following groups: the methodology to do Sciences, the nature of living organisms and the constitution of Universe.