The response of taxonomic and functional diversity of the seed bank to agricultural intensification and soil properties in two Mediterranean cereal areas

Weed seed bank diversity has been severely impacted by agriculture intensifi cation. However, the functional consequences have been poorly studied in highly intensifi ed agro-ecosystems.Postprint (published version

The attractiveness of five common mediterranean weeds to pollinators

Concerns about a global decline in pollinators have called for more knowledge about the factors influencing wild pollinator abundance and diversity in agroecosystems. Agricultural intensification has been identified as the main cause of this “global pollinator crisis”, particularly due to reductions in natural areas holding critical floral and nesting resources. Maintaining native wild plants in agricultural landscapes (e.g., in field margins) is often recommended as a cost-effective and efficient method for pollinator conservation. In this study, the role of common wild flowers, often considered weeds, in supporting pollinators in a Mediterranean agroecosystem was investigated.Postprint (published version

Modification of the optical and structural properties of ZnO nanowires by low-energy Ar+ ion sputtering

The electronic version of this article is the complete one and can be found online at: http://link.springer.com/article/10.1186/1556-276X-8-162The effects of low-energy (≤2 kV) Ar+ irradiation on the optical and structural properties of zinc oxide (ZnO) nanowires (NWs) grown by a simple and cost-effective low-temperature technique were investigated. Both photoluminescence spectra from ZnO NW-coated films and cathodoluminescence analysis of individual ZnO NWs demonstrated obvious evidences of ultraviolet/visible luminescent enhancement with respect to irradiation fluence. Annihilation of the thinner ZnO NWs after the ion bombardment was appreciated by means of high-resolution scanning electron microscopy and transmission electron microscopy (TEM), which results in an increasing NW mean diameter for increasing irradiation fluences. Corresponding structural analysis by TEM pointed out not only significant changes in the morphology but also in the microstructure of these NWs, revealing certain radiation-sensitive behavior. The possible mechanisms accounting for the decrease of the deep-level emissions in the NWs with the increasing irradiation fluences are discussed according to their structural modificationsThis work has been supported by the MICINN (project no. MAT2010-15206) and the EU (COST Action MP0805

Solución de la ecuación de cauchy - euler por medio de la transformada de mellin

En el presente trabajo se da una solución de una ecuación diferencial lineal ordinaria no homogénea con coeficientes variables, caso Cauchy – Euler, haciendo uso de la técnica de las transformadas integrales. La técnica mas apropiada para la solución de la ecuación en mención es la Transformada de Mellin

Solución de la ecuación de cauchy - euler por medio de la transformada de mellin

En el presente trabajo se da una solución de una ecuación diferencial lineal ordinaria no homogénea con coeficientes variables, caso Cauchy – Euler, haciendo uso de la técnica de las transformadas integrales. La técnica mas apropiada para la solución de la ecuación en mención es la Transformada de Mellin

La violencia en los centros escolares de educación secundaria: un estudio multicasos

This paper reports a research project based on case-studies related to bullying practices in Spanish high schools. Our objective was to identify different cultural patterns having influence on the emergence of violent behaviors in centers located in economically deprived areas. ëLack of motivationí, ëlazinessí, ëdisruptionsí, and so on, are key terms and expressions that acquire different meanings depending on who uses them. We found two major groups of teachers: those who blame students for what they regard as studentsí failure, and those who believe that a different teaching approach should be employed with those students. Two different concepts of punishment- in the case of bullying incidents- were also clear: punitive or preventive. In the end, we concluded that exclusive concentration on curricular contents could turn high schools in part of the violence problem. As a contrast, identifying social and cultural problems could be part of the solution. Este artículo refiere un proyecto de investigación realizado mediante estudios de caso sobre la violencia en los centros de Educación Secundaria en España. Nuestro objetivo era identificar aquellas pautas culturales que influyan en la aparición de los comportamientos violentos ubicados en zonas conómicamente desfavorecidas. Términos como “falta de motivación”, “vagancia”, o “interrupciones” son términos y expresiones con diferentes significados según quién los use. Así, encontramos dos grupos de profesores: quienes culpabilizan al estudiante de lo que aquéllos perciben como el fracaso de éste, y un segundo grupo que cree que es necesario emplear diferentes estrategias de enseñanza con este alumnado. Igualmente se perciben dos diferentes conceptos de la sanción académica: la punitiva y la preventiva. Al final zoncluimos que centrarse exclusiva o fundamentalmente en los contenidos del currículo oficial puede llevar a los centros escolares a convertirse en parte del problema de la violencia. Por contra, reconocer los problemas culturales y sociales del alumnado pueden convertir a esos mismos centros en parte de la solución.

La heterogeneidad local y del paisaje no influye en la diversidad funcional de la flora arvense en cultivos cerealistas en clima mediterráneo

Farming intensification and landscape homogenization have been the main cause of plant diversity decline in agro-ecosystems. However, the functional consequences are poorly documented. In this study we analyzed the effects of local and landscape heterogeneity on three functional diversity indices: Functional richness, Functional dispersion and Functional evenness of the emerged weed flora and the seed bank in dryland cereal fields located in Andalusia (Spain)Postprint (published version

Conocimiento didáctico de maestros en formación sobre objetivos de aprendizaje

El proceso de formación de los maestros incluye la familiarización con objetivos específicos de aprendizaje, puesto que su empleo forma parte de la futura labor profesional. Identificar qué objetivos se pueden planificar con una tarea matemática escolar pertenece al ámbito del conocimiento didáctico. En esta comunicación describimos cómo expresan los estudiantes del grado de Educación Primaria de último curso objetivos a partir de una tarea matemática escolar. Los resultados muestran diferencias en las capacidades identificadas, el nivel cognitivo de los contenidos mencionados y la ausencia de consideración de contextos

Weed seed bank diversity in dryland cereal fields: does it differ along the field and between fields with different landscape structure?

n this work, we aimed to test whether taxonomic diversity and functional diversity andthe values of functional traits of the weed seed bank varied across the field, from margins to thecore, and between fields embedded in distinct landscape structures. We sampled the seed bank of 47 conventionally managed cereal fields from two Mediterranean regions in SpainThis work was funded by FEDER (European Regional Development Funds) and the Spanish Ministry of Economy and Competitiveness grants (projects AGL2012-33736 and AGL2015-64130-R). Y.P. was supported by an FPI scholarship (Spanish Ministry of Economy and CompetitivenessPostprint (published version