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11 Páginas ; 3 Figuras ; 3 Tablas ; 1 Apéndice ; The spread of non-indigenous species into new marine habitats represents an increasing threat to global diversity. Genetic techniques provide basic understanding of the invasion processes. The ascidian Microcosmus squamiger is considered to be native to Australia, having been spread worldwide via transoceanic vessels. It has successfully invaded artificial and natural habitats where it has become a pest. We studied phylogeography and genetic structure of 12 M. squamiger populations, including samples from its native range (Australia) and introduced populations from the Indian, Pacific, and Atlantic oceans, as well as the Mediterranean Sea. We amplified 574 bp of the mitochondrial COI gene in 258 individuals and found a total of 52 haplotypes. A haplotype tree revealed two main groups of haplotypes. The relative frequency of each group of haplotypes, multidimensional scaling, and analysis of molecular variance showed important differences between the western Australia localities and the remaining ones (eastern Australia and introduced populations). Furthermore, we found that the colonization of the different areas by M. squamiger has not occurred independently, as many introduced populations shared some low frequency alleles. A nested clade analysis showed a global pattern of restricted gene flow with isolation by distance, although we found episodes of long-distance dispersal in some clades. A contiguous range expansion was detected between Australian populations. We conclude that M. squamiger is native to Australia and has most likely expanded its range of distribution sequentially through worldwide shipping, especially from the harbours of the more populated eastern Australia. In introduced populations, we found a high genetic diversity which suggests enhanced invasive potential. Consequently, there is a need to control this species, as it outcompetes local biota and is an economic threat. ; This research was funded by projects CTM2004-05265, CGL2006-13423, and CTM2007-66635 of the Spanish Government and a FPU scholarship to M. R. from the Spanish 'Ministerio de Educación y Ciencia'. ; Peer reviewed

10 pages, 5 figures, 4 tables.-- Printed version published Aug 2008. ; The European spiny lobster (Palinurus elephas) is a suitable model organism to study the effects of past history and current oceanographic processes on the genetic diversity and population structure of marine species with a long-lived larval phase. A portion of the COI gene was sequenced in 227 individuals from 11 localities, covering most of the present distribution of the species. Divergence was found between Atlantic and Mediterranean regions, which could be explained by restricted gene flow between populations. Moreover, a principal component analysis detected differences within basins. The existence of genetic differentiation between Brittany and Ireland–Scotland populations could be accounted for by the large effect of the Gulf Stream, while mesoscale processes suffered by the incoming Atlantic waters could be responsible of genetic differentiation within the Mediterranean. Furthermore, historical processes could be responsible for a reduction on the overall genetic variability of P. elephas. The haplotypic distribution found in P. elephas, with the presence of one abundant haplotype and a large number of closely related haplotypes, is typical of species experiencing reduction in variability and subsequent expansions. Climatic fluctuations related to glacial cycles could explain the present level of variability and nucleotide diversity found. Interestingly, these glacial events do not seem to have the same impact in other species of the same genus. Our results indicate that recent glacial events could have had a lower impact on Palinurus mauritanicus, a congeneric species that presents an overlapping distribution area but is found in cooler waters than P. elephas. ; This work was supported by a pre-doctoral fellowship awarded by the Autonomous Government of Catalonia to F.P. (2006FIC-00082). Research was funded by projects CGL2006-13423, CTM2004-05625 and CTM2007-66635 from the Ministerio de Educación y Ciencia and 119/2003 from the Spanish Ministerio de Medio Ambiente. The authors are part of the research groups 2005SGR-00191, 2005SGR-00277 and 2005SGR-00995 of the Generalitat de Catalunya. ; Peer reviewed

13 pages, 4 figures, 3 tables ; Background Molecular tools may help to uncover closely related and still diverging species from a wide variety of taxa and provide insight into the mechanisms, pace and geography of marine speciation. There is a certain controversy on the phylogeography and speciation modes of species-groups with an Eastern Atlantic-Western Indian Ocean distribution, with previous studies suggesting that older events (Miocene) and/or more recent (Pleistocene) oceanographic processes could have influenced the phylogeny of marine taxa. The spiny lobster genus Palinurus allows for testing among speciation hypotheses, since it has a particular distribution with two groups of three species each in the Northeastern Atlantic (P. elephas, P. mauritanicus and P. charlestoni) and Southeastern Atlantic and Southwestern Indian Oceans (P. gilchristi, P. delagoae and P. barbarae). In the present study, we obtain a more complete understanding of the phylogenetic relationships among these species through a combined dataset with both nuclear and mitochondrial markers, by testing alternative hypotheses on both the mutation rate and tree topology under the recently developed approximate Bayesian computation (ABC) methods. Results Our analyses support a North-to-South speciation pattern in Palinurus with all the South-African species forming a monophyletic clade nested within the Northern Hemisphere species. Coalescent-based ABC methods allowed us to reject the previously proposed hypothesis of a Middle Miocene speciation event related with the closure of the Tethyan Seaway. Instead, divergence times obtained for Palinurus species using the combined mtDNA-microsatellite dataset and standard mutation rates for mtDNA agree with known glaciation-related processes occurring during the last 2 my. Conclusion The Palinurus speciation pattern is a typical example of a series of rapid speciation events occurring within a group, with very short branches separating different species. Our results support the hypothesis that recent climate change-related oceanographic processes have influenced the phylogeny of marine taxa, with most Palinurus species originating during the last two million years. The present study highlights the value of new coalescent-based statistical methods such as ABC for testing different speciation hypotheses using molecular data. ; This work was supported by a pre-doctoral fellowship awarded by the Autonomous Government of Catalonia to FP (2006FIC-00082). Joao Lopes is funded by EPSRC grant EP/C533550/1 awarded to MAB. Research was funded by projects CGL2006-13423 and CTM2007-66635 from the Ministerio de Educación y Ciencia. The authors are part of the research group 2009SGR-636, 2009SGR-655 and 2009SGR-1364 of the Generalitat de Catalunya. FP acknowledges EU-Synthesys grant (GB-TAF-4474). ; Peer reviewed

Rare-earth (RE) doped transparent glass-ceramics are presented as very promising materials for optical applications. In this work, Transmission Electron Microscopy techniques have been used to structurally characterize a glass of composition 55SiO2-20Al2O3-15Na 2O-10LaF3 (mol%), doped with 1 mol% Tm2O 3, and the corresponding glass-ceramic. The proposed crystallization mechanism for this glass has been modified from the results obtained through advanced STEM/EDXS techniques. The parent glass contains phase separated regions mainly enriched in F and La and also in Al, Si and Tm. After annealing, 10-20 nm LaF3 nano-crystals are formed from these phase separated droplets. The partial incorporation of the doping Tm3+ ions into the LaF 3 nano-crystals has been verified and the interphase crystal/glassy matrix has been more precisely characterized through EDXS. An Al enriched layer is formed around the crystals followed by a Si enriched shell, which greatly increase the viscosity in the periphery of the crystals, inhibiting further crystal growth and thus, keeping the nano size of the crystals. © 2013 The Royal Society of Chemistry. ; The authors acknowledge the financial support of the project MAT2010-20459 of Spanish Government and the FhG Internal Programs under Grant No. Attract 692 280. ; Peer Reviewed

Comunicación presentada en el XV Foro Internacional sobre la evaluación de la Calidad de la Investigación y de la Educación Superior (FECIES). Santander (España), 10-12 de mayo de 2018 ; El profesorado debe estar preparado para formar a personas que convivan en una sociedad democrática, en la que cada individuo tenga una alfabetización científica que le permita ser crítico, responsable, comprometido y conozca el mundo para poder transformarlo. Para ello el o la estudiante debe ser protagonista de su propio aprendizaje y éste debe producirse dentro y fuera del aula. Bajo esta concepción, un grupo de docentes de las áreas de Didáctica de las Ciencias Experimentales y de las Matemáticas, miembros del Grupo de Investigación GICE-DICEMA, ejerce su docencia en los Grados de Magisterio de Educación Infantil y Primaria e investiga en colaboración con profesorado y centros educativos de Infantil y Primaria. En esta comunicación se presentan actividades docentes (dramatizaciones para aprender y enseñar ciencias; actividades sobre la igualdad de género en la ciencia; proyectos para conocer y mejorar el entorno; retos y comunidades de aprendizaje para trabajar dentro y fuera del aula las matemáticas y las ciencias en la vida cotidiana con un enfoque crítico) e investigaciones realizadas en este ámbito, como el proyecto I+D EDU2014-56118-P. Los resultados evidencian la necesidad de formación docente para trabajar con recursos y actividades que persigan el cambio educativo y la Justicia Social ; Teachers must be prepared to train people who live together in a democratic society, in which each individual has a scientific literacy that allows him or her to be critical, responsible, committed and know the world to be able to transform it. So the student must be protagonist in his or her own learning and this must occur inside and outside the classroom. Based on this concept, a group of professors in experimental science and mathematics teaching, members of the research group GICE-DICEMA, teaches in early childhood and primary ...

Trabajo presentado al SPIE Photonic West: Optical Components and Materials XV, celebrado en San Francisco, California (USA) del 29 al 31 de enero de 2018. ; Transparent oxyfluoride glass-ceramics obtained by the adequate heat treatment of Nd3+-doped glass with composition SiO2-Al2O3-Na2O-LaF3 are investigated. X-ray diffraction (XRD) and high resolution transmission electron microscopy (HR-TEM) show that the precipitated nanocrystals are LaF3 with a crystal size between 9-12 nm. Furthermore, energy dispersive X-ray (EDX) analysis shows the incorporation of Nd3+ ions into the LaF3 nanocrystals. Site-selective and time-resolved emission and excitation spectra of the 4F3/2 and 4F5/2 states, allows to unambiguously isolate the emission of Nd3+ ions in LaF3 nanocrystals which shows well defined spectra, similar to those obtained for pure LaF3 crystal. ; This work was supported by the Spanish Government MEC under Projects No. MAT2013-48246-C2-1-P, MAT2013-48246-C2-2-P, and MAT2017-87035-C2-2-P and the University of the Basque Country PPG17/07. ; Peer Reviewed

This article belongs to the Special Issue Preparation and Application of Nanostructured Glass–Ceramics and Nanocomposites. ; Transparent oxyfluoride glass–ceramics containing NaGdF4 nanocrystals were prepared by melt-quenching and doped with Er3+ (0.5 mol%) and different amounts of Yb3+ (0–2 mol%). The selected dopant concentration the crystallization thermal treatments were chosen to obtain the most efficient visible up-conversion emissions, together with near infrared emissions. The crystal size increased with dopant content and treatment time. NaGdF4 NCs with a size ranging 9–30 nm were obtained after heat treatments at Tg + 20–80 °C as confirmed by X-ray diffraction and high-resolution transmission electron microscopy. Energy dispersive X-ray analysis shows the incorporation of rare earth ions into the NaGdF4 nanocrystals. Near-infrared emission spectra, together with the up-conversion emissions were measured. The optical characterization of the glass–ceramics clearly shows that Er3+ and Yb3+ ions are incorporated in the crystalline phase. Moreover, visible up-conversion emissions could be tuned by controlling the nanocrystals size through appropriated heat treatment, making possible a correlation between structural and optical properties. ; This research was funded by Spanish National projects MAT2017-87035-C2-1-P/2-P (AEI/FEDER, UE), Basque Country University PPG17/07 and GIU17/014 and Basque Government PIBA2018-24. This study is part of the dissemination activities of project FunGlass. This project has received funding from the European Union's Horizon 2020 research and innovation program under grant agreement No 739566. This study was also created in the frame of the project Centre for Functional and Surface Functionalized Glass (CEGLASS), ITMS code is 313011R453, operational program Research and innovation, co-funded from European Regional Development Fund. ; Peer reviewed

Transparent NaLuF4 glass-ceramics (GCs) doped with Tm3+ and Tm3+/Yb3+ have been prepared by melting-quenching followed by thermal treatment at temperatures near the glass transition temperature. The crystallization process has been studied using X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM). NaLuF4 nanocrystals (NCs) ranging 9–30 nm in size are the only crystalline phase, the crystal size increasing with the dopant concentration. Energy dispersive X-ray (EDX) measurements confirm the Tm3+ and Yb3+ incorporation in the NCs. Optical characterization included the analysis of up-conversion (UC) as well as the Near-infrared (NIR) luminescence. NIR emission spectra of Tm3+ and Yb3+ in co-doped samples confirmed an efficient energy transfer between both ions. No UC emissions are observed in Tm3+ single-doped glass and GCs. Yb3+ incorporation favors the Tm3+-Tm3+ UC processes resulting in Tm3+ blue, yellowish-red and NIR UC emissions after excitation at 975 nm. Blue UC emission is also observed in the codoped samples after Tm3+ excitation at 791 nm. These effects were more evident for the GCs compared to the base glasses, confirming the RE ions incorporation in the NCs. As a result, these GCs can be used to tune the UC emission from NIR to blue by selective excitation. ; This work was supported by MINECO under Projects MAT2017-87035-C2-1-P/-2-P (AEI/FEDER, UE), Basque Country Government PIBA2018-24 and Basque Country University GIU17/014. This article is part of the dissemination activities of project FunGlass. This project has received funding from the European Union´s Horizon 2020 research and innovation programme under grant agreement No 739566. This article was also created in the frame of the project Centre for Functional and Surface Functionalized Glass (CEGLASS), ITMS code is 313011R453, operational program Research and innovation, co-funded from European Regional Development Fund. This research work has been supported by the Research Agency of the Ministry of Education, Science, Research and Sport of the Slovak Republic, by the project: Advancement and support of R&D for "Centre for diagnostics and quality testing of materials" in the domains of the RIS3 SK specialization, Acronym: CEDITEK II., ITMS2014+ code 313011W442. ; Peer reviewed

[EN] Novel glass-ceramic optical fibers containing NaLuF nanocrystals doped with 0.5ErF and 2YbF (mol%) have been prepared by the rod-in-tube method and controlled crystallization. NaLuF nanocrystals with a size around 20 nm are obtained after heat treatment at 600 °C. Intense upconverted green and red emissions due to (H, S) → I and F → I transitions, respectively, together with a blue emission due to H → I transition have been observed under excitation at 980 nm. The intensity of the green and red upconversion bands shows a nearly linear dependence on the excitation power which can be explained by saturation effects in the intermediate energy states and proves that a sensitized energy transfer upconversion process is responsible for the population of the emitting levels of Er ions. The upconversion emission color changes from yellow to green by increasing the excitation power density which allows to manipulate the color output of the Er emission in the glass-ceramic fibers. The tunable emission color is easily detected with the naked eye. This interesting characteristic makes these glass-ceramic fibers promising materials for photonic applications. ; This work was supported by MINECO under the project MAT2017-87035-C2-1-P/-2-P (AEI/FEDER, UE) and Basque Country University PPG17/07 and GIU17/014, and Basque Government PIBA2018-24. Funding from MPNS Cost Action MP1401 is also acknowledged. This paper is a part of dissemination activities of project FunGlass. This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement no. 739566.