-The growth and nutritional status of newly established Eucalyptus globulus plantations, located in NW Spain, were studied in relation to soil properties and site preparation techniques. Most of the plantations are growing on chemically poorly fertile soils of intermediate depth. Despite being fertilized at establishment, most of the plantations showed low foliar levels of P and Ca, and some showed deficiencies of Mg and K. Growth depended mainly on the altitude, length of the drought period and on concentrations of Ca in soils. Productivity is reflected by the concentrations of Ca in leaves. Preparation of the soil by windrowing reduced levels of Ca, Mg and P in the soil, negatively affecting nutrition and growth and causing an increase in tree mortality. The results suggest subsoiling to be the most suitable site preparation technique for shallow soils, and also indicate the need for repeated fertilization and the adoption of silviculture management practices that enhance the natural turnover of nutrients.Eucalyptus globulus / forest nutrition / forest soils / silviculture / forest growth Résumé -Nutrition et croissance dans les nouvelles plantations d'Eucalyptus globulus du nord ouest de l'Espagne. La croissance et l'état nutritionnel des plantations d'Eucalyptus globulus du nord-ouest de l'Espagne ont été étudiés en fonction des caractéristiques édaphiques et des techniques de préparation du site. La plupart des plantations sont installées sur des sols pauvres de profondeur moyenne. Bien que fertilisées à la plantation, la plupart des plantations révèlent des concentrations foliaires limites en P et Ca, et certaines révèlent des carences en Mg et K. La croissance dépend principalement de l'altitude, de la durée de la période sèche et aussi de la concentration de Ca au sol. La concentration de Ca en feuilles est très représentative de la croissance. L'extraction de litière et les rémanents d'exploitation lors de la préparation du site, réduisent la teneur en Ca, Mg et P du sol, affectant de manière négative la nutrition et la croissance, et aboutissant à une hausse de la mortalité. Ces résultats suggèrent l'idoneité du subsolage comme méthode de préparation du site, la nécessité de fertiliser plusieurs fois et d'adopter une sylviculture qui favorise le renouvellement naturel des nutriments.Eucalyptus globulus / nutrition forestière / sols forestiers / silviculture / croissance forestière

Teaching chemistry in the first years of university education is key in the training of future professionals since, in addition to providing the knowledge of the basic sciences, it contributes to the development of scientific skills that lead to the student to solve real problems, starting from the appropriate search of information in reliable sources and its reading with the purpose of developing analytical, critical and creative skills. Therefore, as a pedagogical innovation strategy, the formulation of a research project in chemistry courses has been implemented since 2016 by the Department of Basic Sciences of the Universidad de La Salle. Within the framework of this strategy, from II-2018 the authors focused on the reflection and implementation of the didactic strategy that depends on the development of scientific competences in the courses of General Chemistry, Organic Chemistry and Biochemistry from tasks, research and learning of current problems in Colombia or in the world.

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The recent literature has shown the importance of Preservice Elementary Science Teachers (PESTs) having a deep understanding of argumentation, as this factor may affect the nature of the class activities that are taught and what students learn. A lack of understanding of this factor may represent an obstacle in the development of science education programmes in line with the development of scientific competences. This paper presents the results of the design and implementation of a training programme of 6 sessions (12 hours of class participation plus 8 hours of personal homework) on argumentation. The programme was carried out by 57 Spanish PESTs from Malaga, Spain. The training programme incorporates the innovative use of certain strategies to improve competence in argumentation, such as teaching PESTs to identify the elements of arguments in order to design assessment rubrics or by including peer assessment during evaluation with and without rubrics. The results obtained on implementing the training programme were evaluated based on the development of PESTs" argumentation competence using Toulmin"s argumentative model. Data collection methods involved two tasks carried out at thebeginning and the end of the programme, i.e., pre-test and post-test, respectively. The conclusion of the study is that students made significant progress in their argumentation competence on completing the course. In addition, PESTs who followed the training programme achieved statistically better results at the end than those in the control group (n = 41), who followed a traditional teaching programme. A 6-month transfer task showed a slight improvement for the PESTs of the experimental group in relation to the control group in their ability to transfer argumentation to practice, especially to the extent to which they mentioned argumentation in their practice portfolios.

eprints@whiterose.ac.uk https://eprints.whiterose.ac.uk/ Reuse Unless indicated otherwise, fulltext items are protected by copyright with all rights reserved. The copyright exception in section 29 of the Copyright, Designs and Patents Act 1988 allows the making of a single copy solely for the purpose of non-commercial research or private study within the limits of fair dealing. The publisher or other rights-holder may allow further reproduction and re-use of this version -refer to the White Rose Research Online record for this item. Where records identify the publisher as the copyright holder, users can verify any specific terms of use on the publisher's website. TakedownIf you consider content in White Rose Research Online to be in breach of UK law, please notify us by emailing eprints@whiterose.ac.uk including the URL of the record and the reason for the withdrawal request. Model-Based Specification of Safety Compliance Needs for CriticalSystems: A Holistic Generic Metamodel! Abstract!Context: Many critical systems must comply with safety standards as a way of providing assurance that they do not pose undue risks to people, property, or the environment. Safety compliance is a very demanding activity, as the standards can consist of hundreds of pages and practitioners typically have to show the fulfilment of thousands of safety-related criteria. Furthermore, the text of the standards can be ambiguous, inconsistent, and hard to understand, making it difficult to determine how to effectively structure and manage safety compliance information. These issues become even more challenging when a system is intended to be reused in another application domain with different applicable standards.Objective: This paper aims to resolve these issues by providing a metamodel for the specification of safety compliance needs for critical systems. Method: The metamodel is holistic and generic, and abstracts common concepts for demonstrating safety compliance from different standards and application domains. Its application results in the specification of Òreference assurance frameworksÓ for safety-critical systems, which correspond to a model of the safety criteria of a given standard. For validating the metamodel with safety standards, parts of several standards have been modelled by both academic and industry personnel, and other standards have been analysed. We further augment this with feedback from practitioners, including feedback during a workshop. Results:The results from the validation show that the metamodel can be used to specify safety compliance needs for aerospace, automotive, avionics, defence, healthcare, machinery, maritime, oil and gas, process industry, railway, and robotics. Practitioners consider that the metamodel can meet their needs and find benefits in its use. Conclusion:The metamodel supports the specification of safety compliance needs for most critical computer-based and software-intensive systems. The resulting models can provide an effective means of structuring and managing safety compliance infor...

En este artículo se presenta un marco teórico de referencia para desarrollar la competencia en alimentación en la educación obligatoria. Los planteamientos seguidos para su elaboración implican salir inicialmente del contexto escolar y situarse en la vida diaria para conocer cuál es la situación actual en nuestra sociedad. De esta forma se puede resaltar qué aspectos son los más necesarios y en cuáles se detectan mayores carencias, para incidir especialmente en ellos. A partir de la definición y delimitación del contexto se caracteriza la competencia en alimentación que un ciudadano debería poseer. Como resultado se describe el marco de referencia para su desarrollo en la educación obligatoria, organizado en torno a siete dimensiones: los alimentos, el funcionamiento del cuerpo con respecto a la nutrición, cocinar, cultivar y elaborar los alimentos, comprar alimentos, comer en compañía, la actividad física y el descanso.

The translation and adaptation of an assessment instrument into another language can be problematic, due, among other reasons, to sociocultural differences. This proved to be the case with the Spanish adaptation of the Students' Understanding of Models in Science (SUMS) questionnaire, a Likert‐type scale developed originally in English. In light of this, and with the additional aim of improving upon certain aspects of the original instrument, we report the development of a new questionnaire for assessing Spanish‐speaking students' understanding of the nature of models and their uses in science, providing validity evidence for the internal structure of the construct measured. The tool was developed by considering various dimensions of this concept that have been described in the literature, as well as the results of studies that piloted the SUMS questionnaire. For each dimension we drew up a set of items that could be rated using a Likert‐type scale; half of these items were positively worded with respect to an adequate understanding of models, and half were reverse worded. The adequacy of the proposed items was first assessed by a panel of experts, following which we examined the score structure obtained with the resulting instrument by administering it to a sample of 1272 students aged between 14 and 55 years. After purifying the instrument based on the results of these analyses, we obtained a final version of the questionnaire comprising 20 items distributed equally across four subscales: Beyond exact replicas, Purpose of models, Multiple models, and Changing models. The results obtained through factor analysis and structural equation modeling provide validity evidence for the internal structure of the construct measured. The questionnaire is quick to administer and is applicable to students across a wide range of ages and levels of education, including prospective science teachers.