The potential of juniperus thurifera to sequester carbon in semi-arid forest soil in Spain

Producción CientíficaThe main purpose of this work is to show the influence of vegetation in the storage and stabilisation of organic carbon in semi-arid Juniperus thurifera (J. thurifera) forest soil in central Spain. The variability of the organic matter storage with factors such as sex, trunk diameter and the protection of the canopy of the tree has been analysed. The distribution of the soil organic carbon (SOC) into different fractions has also been determined, in order to estimate the stability of the organic matter. The results show that the SOC concentration has no dependence on the sex of the tree, but it increases with the diameter of the trunk and under the protection of the tree canopy. This study found that the organic matter of the J. thurifera forest soil has a high proportion of recalcitrant organic fraction, humin, which suggests that, given its organic matter stability, J. thurifera forest soils could be a real carbon sink. Consequently, the conservation of this type of old forest ecosystem is important for promoting carbon sequestration.Junta de Castilla y León (projects VA094A06 and VA014A07)Ministerio de Educación y Formación Profesional (MEC) (project CTM2006-02249/TECNO

Dirac Green function for δ potentials

Física Teórica. Atómica y Óptic

Application of chemometrics on Raman spectra from Mars: Recent advances and future perspectives

Producción CientíficaThe SuperCam and SHERLOC instruments onboard the NASA/Perseverancerover are returning the first Raman spectra to be ever collected from anotherplanet. Similarly, the RLS instrument onboard the ESA/Rosalind Franklinrover will collect Raman spectra from powdered rocks sampled from thesubsurface of Mars. To optimize the scientific exploitation of Raman spectrareturned from planetary exploration missions, tailored chemometric tools arebeing developed that take into account the analytical capability of the men-tioned Raman spectrometers. In this framework, the ERICA research groupis using laboratory simulators of SuperCam and RLS to perform representa-tive laboratory studies that will enhance the scientific outcome of bothMars2020 and ExoMars missions. On one hand, preliminary studies provedthe chemometric analysis of RLS datasets could be used to obtain a reliablesemi-quantitative estimation of the main mineral phases composing Martiangeological samples. On the other hand, it was proved the data fusion ofRaman and LIBS spectra gathered by SuperCam could be used to enhancethe discrimination of mineral phases from remote geological targets. Besidesdescribing the models developed by the ERICA group, this work presents anoverview of the complementary chemometric approaches so far tested in thisfield of study and propose further improvements to be addressed in thefuture.Ministerio de Economía y Competitividad, Beca/Concesión Número:PID2019-107442RBC31European Union’s Horizon 2020 research and innovation program. grant agreement no. 68730

Semi‐quantification of binary saline solutions by Raman spectroscopy: Implications for Europa

Producción CientíficaThe Europa lander is a concept for a potential future planetary exploration mission which purpose is to characterize the icy shell of Europa and to search for organics. To achieve this objective, the current concept of the lander includes a Raman spectrometer, such as RLS instrument, that could be able to analyze (sub) surface targets in their solid and liquid form. Knowing that ice and brines of Europa are potentially enriched by sulfate and chlorides, this work seeks to evaluate if Raman spectroscopy could be used to semi quantify the saline content of water solutions using space-like instrumentation. To do so, MgSO4 and MgCl2 were used to prepare three sets of water solutions. Raman analyses were then performed by the laboratory simulator of the ExoMars Raman Laser Spectrometer (RLS), which has been defined as the threshold system for the Europa Lander. After data analysis, two different semi-quantification approaches were tested, and their results compared. Although univariate calibration curves proved to successfully quantify the content of SO42− and Cl− anions dissolved in mono-analyte water solutions, this strategy provided very poor results when applied to binary saline mixtures. Overcoming this issue, the non-linearity prediction ability of Artificial Neural Networks (ANNs) in combination with bandfitting allows to successfully resolve the complexity of the vibrational perturbation suffered by the OH region, which is caused by the cross interaction of H2O molecules with different anions.Ministerio de Economía y Competitividad, Grant/Award Number: PID2019-107442RBC31

Machine learning methods applied to combined Raman and LIBS spectra: Implications for mineral discrimination in planetary missions

Producción CientíficaThe combined analysis of geological targets by complementary spectroscopic techniques could enhance the characterization of the mineral phases found on Mars. This is indeed the case with the SuperCam instrument onboard the Perseverance rover. In this framework, the present study seeks to evaluate and compare multiple machine learning techniques for the characterization of carbonate minerals based on Raman-LIBS (Laser-Induced Breakdown Spectroscopy) spectroscopic data. To do so, a Ca-Mg prediction curve was created by mixing hydromagnesite and calcite at different concentration ratios. After their characterization by Raman and LIBS spectroscopy, different multivariable machine learning (Gaussian process regression, support vector machines, ensembles of trees, and artificial neural networks) were used to predict the concentration ratio of each sample from their respective datasets. The results obtained by separately analyzing Raman and LIBS data were then compared to those obtained by combining them. By comparing their performance, this work demonstrates that mineral discrimination based on Gaussian and ensemble methods optimized the combine of Raman-LIBS dataset outperformed those ensured by Raman and LIBS data alone. This demonstrated that the fusion of data combination and machine learning is a promising approach to optimize the analysis of spectroscopic data returned from Mars.Agencia Estatal de Investigación, grant (PID2022-142490OB-C32)Ministerio de Economía y Competitividad (MINECO),Grant/Award Number (RDE2018-102600-T

The Raman laser spectrometer ExoMars simulator (RLS Sim): A heavy‐duty Raman tool for ground testing on ExoMars

Producción CientíficaThe Raman laser spectrometer (RLS) instrument onboard the Rosalind Franklin rover of the ExoMars 2022 mission will analyze powdered samples on Mars to search for traces of life. To prepare for the mission, the RLS scientific team has developed the RLS ExoMars Simulator (RLS Sim), a flexible model of RLS that operates similarly to the actual instrument, both in laboratory and field conditions, while also emulating the rover operational constraints in terms of sample distribution that are relevant to the Raman analysis. This system can operate autonomously to perform RLS-representative analysis in one or several samples, making it very useful to perform heavy experimental tasks that would otherwise be impossible using a flight-representative model of the instrument. In this work, we introduce the current configuration of the RLS Sim that has incorporated new hardware elements such as the RAman Demonstrator 1 (RAD1) spectrometer with the objective of approaching its performance to that of the actual RLS instrument. To evaluate the scientific capability of the RLS Sim, we have compared it with a replica model of RLS, the RLS Flight Spare (FS). Several acquisition aspects have been evaluated based on the analysis of select samples, assessing the performance in terms of spectral range and resolution and also studying several issues related to the evolution of signal-to-noise ratio (SNR) with different acquisition parameters, especially the number of accumulations. This performance analysis has shown that the RLS Sim in its updated configuration will be a key model to perform support science for the ExoMars mission and the RLS instrument on the Rosalind Franklin rover. Designed to work intensively, the use of the RLS Sim in combination with the RLS FS will facilitate maximizing the scientific return of the RLS spectrometer during Martian operations.Secretaría de Estado de Investigación, Desarrollo e Innovación (grant PID2019-107442RBC31)European Union’s Horizon 2020 research and innovation program (grant 687302

Congreso Internacional sobre Investigación en Didáctica de las Ciencias (9º. 2013. Girona)

En este trabajo se quiere poner de manifiesto la importancia que conlleva una adecuada formación del futuro profesor de educación primaria en los contenidos del ámbito de la salud. Se analiza cómo tiene lugar la enseñanza de estos contenidos dentro del ámbito universitario en la Universidad de Valladolid, en relación a los planes de estudio actuales así como a la legislación existente del currículum de educación primaria. Dentro de las competencias que ha de adquirir el futuro docente se contemplan aquellas que se adquieren a través de experiencias motivadoras en su paso por las aulas universitarias. Con este enfoque es con el que se ha planteado la impartición de las enseñanzas que se contemplan en la asignatura de educación para la salud en Educación Primaria. Se propone para este tipo de enseñanza una metodología indagatoria para que los futuros maestros adquieran las competencias necesarias en el ámbito de la salud. El uso del material didáctico que ofrece el proyecto europeo PROFILES («Professional Reflection-OrientedFocusonInquiry-basedLearning and EducationthroughScience», así como su filosofía de la enseñanza-aprendizaje basada en la indagación hace posible llevar la estrategia al aula

Congreso Internacional sobre Investigación en Didáctica de las Ciencias (9º. 2013. Girona)

El presente trabajo aborda la problemática entorno a la enseñanza-aprendizaje de las ciencias en el ámbito de las enseñanzas no-universitarias como resultado de los últimos estudios PISA en relación a nuestros estudiantes españoles. Con el propósito de desentrañar los aspectos que fallan en la práctica docente así como tratar de mejorar e intensificar los que pueden contribuir a mejorar la cultura científica, se lleva a cabo un estudio utilizando la técnica Delphi. La técnica es adecuada para llevar a cabo una investigación en el área de la didáctica de las ciencias, pues una de las fortalezas que tiene es no requerir de la presencia de los expertos ya que se puede realizar por e-mail. El método busca encontrar el consenso entre los expertos encuestados. A través de sucesivas encuestas a más de 100 personas elegidas de entre diferentes estamentos relacionados con el ámbito de las ciencias tratamos de encontrar las claves para mejorar las clases de ciencias y enfatizar la necesidad de mejorar la cultura científica de nuestros estudiantes

Congreso de Docentes de Ciencias (2º. 2012. Madrid)

En este trabajo tratamos de identificar los puntos clave en los distintos campos de las ciencias que pueden mejorar la cultura científica en la sociedad actual. Numerosos autores están de acuerdo en la importancia de mejorar e intensificar la cultura científica en la sociedad en general, y más en particular en los alumnos durante la enseñanza preuniversitaria. Sin embargo, resulta difícil desentrañar qué aspectos fallan en la práctica educativa, así como cuáles se consideran los tópicos de una buena cultura y educación científica. A través del empleo de la técnica Delphi recogemos las opiniones de más de un centenar de individuos pertenecientes a los distintos colectivos relacionados con el ámbito de las ciencias y su enseñanza. En este trabajo presentamos los resultados preliminares de lo que será un estudio más extenso.In this work we try to identify the key points in the various fields of science that can improve the scientific culture in today’s society. Numerous authors have agreed on the importance of improving and intensifying scientific culture in society in general, and more particularly among the students before university. However, it is difficult to unravel what fails in educational practice as well as what are the topics of a good culture and science education. Through the use of the Delphi technique we collect the views of more than one hundred individuals belonging to the different groups related to the field of science and teaching. In this paper we present preliminary results of what will be a more extensive study

Spectroscopic study of terrestrial analogues to support rover missions to Mars – a Raman-centred review

Producción CientíficaThe 2020s could be called, with little doubt, the "Mars decade". No other period in space exploration history has experienced such interest in placing orbiters, rovers and landers on the Red Planet. In 2021 alone, the Emirates' first Mars Mission (the Hope orbiter), the Chinese Tianwen-1 mission (orbiter, lander and rover), and NASA's Mars 2020 Perseverance rover reached Mars. The ExoMars mission Rosalind Franklin rover is scheduled for launch in 2022. Beyond that, several other missions are proposed or under development. Among these, MMX to Phobos and the very important Mars Sample Return can be cited. One of the key mission objectives of the Mars 2020 and ExoMars 2022 missions is the detection of traces of potential past or present life. This detection relies to a great extent on the analytical results provided by complementary spectroscopic techniques. The development of these novel instruments has been carried out in step with the analytical study of terrestrial analogue sites and materials, which serve to test the scientific capabilities of spectroscopic prototypes while providing crucial information to better understand the geological processes that could have occurred on Mars. Being directly involved in the development of three of the first Raman spectrometers to be validated for space exploration missions (Mars 2020/SuperCam, ExoMars/RLS and RAX/MMX), the present review summarizes some of the most relevant spectroscopy-based analyses of terrestrial analogues carried out over the past two decades. Therefore, the present work describes the analytical results gathered from the study of some of the most distinctive terrestrial analogues of Martian geological contexts, as well as the lessons learned mainly from ExoMars mission simulations conducted at representative analogue sites. Learning from the experience gained in the described studies, a general overview of the scientific outcome expected from the spectroscopic system developed for current and forthcoming planetary missions is provided.Ministerio de Economía, Industria y Competitividad (grants PID2019-107442RB-C31 and RDE2018-102600-T)Consejo Europeo de Investigación (grant 687302