Lattice dynamics study of cubic Tb2O3

"This is the peer reviewed version of the following article: Ibáñez, Jordi, Oriol Blázquez, Sergi Hernández, Blas Garrido, Plácida Rodríguez-Hernández, Alfonso Muñoz, Matias Velázquez, Philippe Veber, and Francisco Javier Manjón. 2018. Lattice Dynamics Study of Cubic Tb 2 O 3. Journal of Raman Spectroscopy 49 (12). Wiley: 2021 27. doi:10.1002/jrs.5488, which has been published in final form at https://doi.org/10.1002/jrs.5488. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving."[EN] We report a joint experimental and theoretical study of the lattice dynamics of cubic Tb2O3. Up to 16 optical Raman-active modes have been observed with polarized and unpolarized Raman scattering measurements on a high-quality Tb2O3 single crystal. The measured wavenumbers have been compared with those of other rare-earth (RE) and related sesquioxides with cubic (C-type or bixbyite) structure. First-principles calculations have allowed us to assign the symmetry of the experimentally observed Raman-active modes. Additional lattice-dynamical calculations on the related cubic RE sesquioxides Dy2O3, Gd2O3, Eu2O3, and Sm2O3 indicate that the phonon wavenumbers of the Raman-active modes in these compounds are monotonically reduced with increasing the lattice parameter along the Dy2O3-Tb2O3-Gd2O3-Eu2O3-Sm2O3 series, thus prompting for a revision of the experimental Raman spectra of some of these compounds (mainly Eu2O3 but also Gd2O3).This study was supported by the Spanish Ministerio de Economía y Competitividad under Projects MAT2015-71070-REDC, MAT2015-71035-R, MAT2016-75586-C4-2-P/3-P, and FIS2017-2017-83295-P.Ibanez, J.; Blazquez, O.; Hernandez, S.; Garrido, B.; Rodríguez-Hernández, P.; Munoz, A.; Velazquez, M.... (2018). Lattice dynamics study of cubic Tb2O3. 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The value of scientific information on climate change: a choice experiment on Rokua esker, Finland

This article presents an application of the choice experiment method in order to provide estimates of economic values generated by water quantity improvements in the environment. More importantly, this is the first choice experiment study valuing scientific information and in particular scientific information on climate change. The case study of interest is Rokua in Northern Finland, a groundwater dependent ecosystem very sensitive to climate change and natural variability. The study deals with the uncertainty about the actual dynamics of the system and the effect of future climate change by exploring whether the public values sustained provision of resources for scientific research to better understand long-term environmental changes in Rokua. Data are analysed using a nested multinomial logit and an error component model. Evidence from this study suggests that individuals are willing to pay in order to assure scientific research so as to better understand long-term environmental changes. As a result, policy should consider investing in and supporting related research. Other aspects of water management policy valued by the public are water quantity, recreation, and total land income. We gratefully acknowledge the financial support from the European Union via the 7th Framework Program GENESIS: Groundwater and dependent ecosystems: New Scientific basis on climate change and land-use impact for the update of the EU Groundwater Directive; WP-6 Groundwater systems management: scenarios, risk assessment, cost-efficient measures and legal aspects. We finally thank two anonymous referees for constructive and insightful comments Koundouri, P.; Kougea, E.; Stithoua, M.; Ala-Ahob, P.; Eskelinenb, R.; Karjalainenc, T.; Klove, B.... (2012). The Value of Scientific Information on Climate Change: A Choice Experiment on Rokua esker, Finland. Journal of Environmental Economics and Policy. 1(1):85-102. doi:10.1080/21606544.2011.647450 Senia 85 102 1

Modelado conceptual de juegos serios: revisión sistemática de la literatura

Los Juegos Serios (Serious Games o SG) son todos aquellos cuyo objetivo no es, únicamente, promover un mero entretenimiento, sino también estimular el aprendizaje o la adquisición de un conocimiento o habilidad. Actualmente, hay una tendencia en el mercado a la generación de este tipo de juegos. Dada la importancia de la conceptualización del dominio de un problema y de su solución, en este trabajo se presenta el desarrollo de un mapeo sistemático de la literatura (en inglés, systematic mapping study o SMS) con el propósito de identificar el estado del arte y descubrir las contribuciones que existen en relación con el modelado conceptual de juegos serios. Se realizó una búsqueda en las librerías digitales Scopus, IEEE Xplore y ACM desde enero del año 2010 a junio del año 2021. De un total de 558 artículos encontrados, se analizaron 31 estudios primarios. Se evidenció que UML1 es el lenguaje de modelado predominante para el modelado de Juegos serios, aunque se utilizan otros lenguajes como UP4EG, DSML, Deterministic Finite Automaton (DFA), Discrete Event System Specification (DEVS) y Fuzzy Inference Systems (FIS). Dentro de los diagramas UML, los predominantes son los diagramas de clases y diagramas de actividad. El 30% de los estudios primarios proponen un framework y en el mismo porcentaje (30 %) de los artículos propone una metodología para el desarrollo de Juegos serios. De los frameworks encontrados, la mayoría no especifican la manera para realizar el modelado conceptual.Workshop: WIS - Ingeniería de SoftwareRed de Universidades con Carreras en Informátic

Combined fit to the spectrum and composition data measured by the Pierre Auger Observatory including magnetic horizon effects

The measurements by the Pierre Auger Observatory of the energy spectrum and mass composition of cosmic rays can be interpreted assuming the presence of two extragalactic source populations, one dominating the flux at energies above a few EeV and the other below. To fit the data ignoring magnetic field effects, the high-energy population needs to accelerate a mixture of nuclei with very hard spectra, at odds with the approximate E$^{-2}$ shape expected from diffusive shock acceleration. The presence of turbulent extragalactic magnetic fields in the region between the closest sources and the Earth can significantly modify the observed CR spectrum with respect to that emitted by the sources, reducing the flux of low-rigidity particles that reach the Earth. We here take into account this magnetic horizon effect in the combined fit of the spectrum and shower depth distributions, exploring the possibility that a spectrum for the high-energy population sources with a shape closer to E$^{-2}$ be able to explain the observations