El aprendizaje de la función cuadrática con tabletas a través del proceso de modelización

Analizamos cualitativamente la implementación de un modelo de enseñanza y aprendizaje diseñado para trabajar la función cuadrática con tabletas a través de la modelización matemática de un fenómeno de la vida real en un grupo de 1º de bachillerato. El fenómeno estudiado es la relación entre el tiempo y la altura de una pelota dejada caer desde una cierta altura considerando solo el primer salto. El análisis de los datos revela que la realización de un estudio previo de las propiedades cualitativas del fenómeno y los conocimientos previos de los estudiantes, son clave en la elección de la función usada como modelo así como también en la interpretación de los resultados en términos del fenómeno. También se observa que los estudiantes presentan concepciones arraigadas sobre el concepto de altura

Ordovician and Silurian igneous rocks and orthogeneisses in the Catalonian Coastel Ranges

These rocks exhibit calc-alkaline affinities and may have originated by partial melting of the crust in a post-collision, anorogenic setting. Orthogneisses derived from biotite-bearing leucogranites occur within aprobably cambrian heterogeneous series. Petrological and geochemical features suggest that they might be genetically related to the ordovician vulcanites. Basic sills and volcanoclastic rocks occur intercalated within a mainly pelitic formation in the lower part of the Silurian sequence. The silurian igneous rocks are alkali basalts and may reflect an extensional regime

Ordovician and Silurian igneous rocks and orthogeneisses in the Catalonian Coastel Ranges

These rocks exhibit calc-alkaline affinities and may have originated by partial melting of the crust in a post-collision, anorogenic setting. Orthogneisses derived from biotite-bearing leucogranites occur within aprobably cambrian heterogeneous series. Petrological and geochemical features suggest that they might be genetically related to the ordovician vulcanites. Basic sills and volcanoclastic rocks occur intercalated within a mainly pelitic formation in the lower part of the Silurian sequence. The silurian igneous rocks are alkali basalts and may reflect an extensional regime

Simulation and comparative analysis of waste in concrete slabs

Construction sector generates significant amounts of waste that affects the environment and obstructs a sustainable development. The horizontal structure (slabs and roofs) is one of the building elements, by its functional requirement (geometry and layout) and volume, who uses more raw material for its constitution (potential generators of waste) On the other hand, the choice of the system to use, is typically based on criteria such as the ease of construction, the economy availability or the technological feasibility; so, from a sustainable perspective, the generation of waste has not been considered or evaluated. This work compares and analyzes four different common elements used in slabs and the possible generation of waste produced for the construction and eventual demolition of them, in order to provide a new weighting criterion in the choice.Peer ReviewedPostprint (published version

A qualitative methodology to reduce features in classification problems

In this paper, a preliminary methodology which quantifies the dependence between features in a data set by using the Ameva discretization algo rithm and the advantages of a qualitative model is developed. Thus, different matrices of inter dependence are built providing a grade of depen dence between two features. This methodology is applied to a well-known data set, obtaining promis ing results for the carried out system.Ministerio de Ciencia e Innovacion TIN2009-14378-C02-01 (ARTEMISA

Lucilia sericata strain from Colombia: Experimental Colonization, Life Tables and Evaluation of Two Artifcial Diets of the Blowfy Lucilia sericata (Meigen) (Diptera: Calliphoridae), Bogotá, Colombia Strain

The objective of this work was to establish, under experimental laboratory conditions, a colony of Lucilia sericata, Bogotá-Colombia strain, to build life tables and evaluate two artifcial diets. This blowfy is frequently used in postmortem interval studies and in injury treatment. The parental adult insects collected in Bogotá were maintained in cages at 22°C±1 average temperature, 60%±5 relative humidity and 12 h photoperiodicity. The blowfies were fed on two artifcial diets that were evaluated over seven continuous generations. Reproductive and population parameters were assessed. The life cycle of the species was expressed in the number of days of the different stages: egg = 0.8±0.1, larvae I = 1.1±0.02, larvae II = 1.94±0.16, larvae III = 3.5±0.54, pupae = 6.55±0.47, male adult = 28.7±0.83 and female adult = 33.5±1.0. Total survival from egg stage to adult stage was 91.2% for diet 1, while for diet 2 this parameter was 40.5%. The lifetime reproductive output was 184.51±11.2 eggs per female. The population parameters, as well as the reproductive output of the blowfies that were assessed, showed relatively high values, giving evidence of the continuous increase of the strain over the different generations and making possible its maintenance as a stable colony that has lasted for more than two years

The nitrogen contribution of different plant parts to wheat grains: exploring genotype, water, and nitrogen effects

The flag leaf has been traditionally considered as the main contributor to grain nitrogen. However, during the reproductive stage, other organs besides the flag leaf may supply nitrogen to developing grains. Therefore, the contribution of the ear and other organs to the nitrogen supplied to the growing grains remains unclear. It is important to develop phenotypic tools to assess the relative contribution of different plant parts to the N accumulated in the grains of wheat which may helps to develop genotypes that use N more efficiently. We studied the effect of growing conditions (different levels of water and nitrogen in the field) on the nitrogen contribution of the spike and different vegetative organs of the plant to the grains. The natural abundance of 15 δ N and total N content in the flag blade, peduncle, whole spike, glumes and awns were compared to the 15 δ N and total N in mature grains to trace the origin of nitrogen redistribution to the grains. The 15 δ N and total N content of the different plant parts correlated positively with the 15 δ N and total N content of mature grains suggesting that all organs may contribute a portion of their N content to the grains. The potential contribution of the flag blade to grain N increased (by 46%) as the growing conditions improved, whereas the potential contribution of the glumes plus awns and the peduncle increased (46 and 31%, respectively) as water and nitrogen stress increased. In general, potential contribution of the ear providing N to growing grains was similar (42%) than that of the vegetative parts of the plants (30-40%), regardless of the growing conditions. Thus, the potential ear N content could be a positive trait for plant phenotyping, especially under water and nitrogen limiting conditions. In that sense, genotypic variability existed at least between old (tall) and modern (semidwarf) cultivars, with the ear from modern genotypes exhibiting less relative contribution to the total grain N. The combined use of 15 δ N and N content may be used as an affordable tool to assess the relative contribution of different plant parts to the grain N in wheat