Repercusiones de la teoría de Piaget en los diseños curriculares

This paper contains part of the results obtained in a research study on the repercussions of Piaget�s theory on education. The general frame of the study is presented and the exposition is restricted to analysing its influence on preschool and early primary school curricular design. The results show that only the structural aspects of the theory are taken into account, and that there is a tendency towards the mechanical transposition of both principles and contents of Piaget�s theory to education. In the discussion it is shown that if the epistemological vocation of genetic psychology is taken into account and if a profound study of the nature of education is made, it is possible to conceive new fields of application of genetic theory, different from educational aims, and a more suitable methodology for carrying out this applicationrealizada acerca de las repercusiones de Piaget en los ambientes educativos. Se presenta el marco general de la investigación y se centra la exposición en el análisis de la influencia en los diseños curriculares. El texto seleccionado para dicho análisis fue el relativo a las Orientaciones y Programas para Parvulario y Ciclo Inicial editado por la Generalitat de Cataluña. Los resultados evidencian una centración en los aspectos estructurales de la teoría genética y una tendencia hacia la extrapolación de los principios y contenidos de la teoría genética a la situación educativa. En la discusión se demuestra como una toma de conciencia de la vocación epistemológica de los datos psicogenéticos, unida a una mayor profundización de la naturaleza de la educación, permite concebir nuevos campos de aplicación de la teoría genética, distintos al de la elección y organización de los objetivos educativos, así como la metodología más pertinente para llevar a cabo esa aplicació

Absorbing phase transition from a structured active particle phase

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Strigolactones: new players in the nitrogen‐phosphorus signalling interplay

Nitrogen (N) and phosphorus (P) are among the most important macronutrients for plant growth and development, and the most widely used as fertilizers. Understanding how plants sense and respond to N and P deficiency is essential to optimize and reduce the use of chemical fertilizers. Strigolactones (SLs) are phytohormones acting as modulators and sensors of plant responses to P deficiency. In the present work, we assess the potential role of SLs in N starvation and in the N-P signalling interplay. Physiological, transcriptional and metabolic responses were analysed in wild-type and SL-deficient tomato plants grown under different P and N regimes, and in plants treated with a short-term pulse of the synthetic SL analogue 2′-epi-GR24. The results evidence that plants prioritize N over P status by affecting SL biosynthesis. We also show that SLs modulate the expression of key regulatory genes of phosphate and nitrate signalling pathways, including the N-P integrators PHO2 and NIGT1/HHO. The results support a key role for SLs as sensors during early plant responses to both N and phosphate starvation and mediating the N-P signalling interplay, indicating that SLs are involved in more physiological processes than so far proposedFil: Marro, Nicolás Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina. Czech Academy of Sciences. Institute of Botany; República ChecaFil: Lidoy, Javier. Estación Experimental del Zaidín. Department of Soil Microbiology and Symbiotic Systems; EspañaFil: Chico, María Ángeles. Estación Experimental del Zaidín. Department of Soil Microbiology and Symbiotic Systems; EspañaFil: Rial, Carlos. Universidad de Cádiz; EspañaFil: García, Juan. Estación Experimental del Zaidín. Department of Soil Microbiology and Symbiotic Systems; EspañaFil: Varela, Rosa M.. Universidad de Cádiz; EspañaFil: Macías, Francisco A.. Universidad de Cádiz; EspañaFil: Pozo, María J.. Estación Experimental del Zaidín. Department of Soil Microbiology and Symbiotic Systems; EspañaFil: Janoušková, Martina. Institute of Botany of the Czech Academy of Sciences; República ChecaFil: López-Ráez, Juan A.. Estación Experimental del Zaidín. Department of Soil Microbiology and Symbiotic Systems; Españ