Aumentar competencias y motivación mediante la participación en competiciones matemáticas

Cabe prestar atención a la desmotivación que los alumnos manifiestan ante el aprendizaje de las Matemáticas por razones como la desconexión manifiesta entre lo que aprenden y el entorno real (Fernández y Pérez, 2011), la dificultad al realizar los distintos problemas surgidos, la falta de metodologías de trabajo donde se intensifique el trabajo en equipo y cooperativo (Hidalgo et al, 2004). Así como la heterogeneidad mostrada en el alumnado actual siendo muchos los niveles presentes en un aula. Las competiciones matemáticas, como Olimpiadas o Pruebas Cangur, y, sobre todo, las sesiones de preparación a éstas, aúnan muchas de las características que adolecen en las actividades de enseñanza-aprendizaje presentadas en el aula de Matemáticas

Combined Effects of the North Atlantic Oscillation and the Arctic Oscillation on Sea Surface Temperature in the Alborán Sea

We explored the possible effects of the North Atlantic Oscillation (NAO) and Arctic Oscillation (AO) on interannual sea surface temperature (SST) variations in the Albora´n Sea, both separately and combined. The probability of observing mean annual SST values higher than average was related to NAO and AO values of the previous year. The effect of NAO on SST was negative, while that of AO was positive. The pure effects of NAO and AO on SST are obscuring each other, due to the positive correlation between them. When decomposing SST, NAO and AO in seasonal values, we found that variation in mean annual SST and mean winter SST was significantly related to the mean autumn NAO of the previous year, while mean summer SST was related to mean autumn AO of the previous year. The one year delay in the effect of the NAO and AO on the SST could be partially related to the amount of accumulated snow, as we found a significant correlation between the total snow in the North Albora´n watershed for a year with the annual average SST of the subsequent year. A positive AO implies a colder atmosphere in the Polar Regions, which could favour occasional cold waves over the Iberian Peninsula which, when coupled with precipitations favoured by a negative NAO, may result in snow precipitation. This snow may be accumulated in the high peaks and melt down in spring-summer of the following year, which consequently increases the runoff of freshwater to the sea, which in turn causes a diminution of sea surface salinity and density, and blocks the local upwelling of colder water, resulting in a higher SST.CGL2009-11316 (Ministerio de Ciencia e Innovación, Spain, and FEDER

School leadership. A review of current research perspectives

Ante el fracaso –o los efectos muy limitados- de muchas de las reformas externas intentadas en las últimas décadas, el liderazgo educativo es percibido como un elemento clave para generar mejora desde abajo, creando condiciones institucionales que hagan más eficaces las organizaciones escolares. A partir de una revisión de la literatura internacional actual, este artículo se propone delimitar algunos de los enfoques relevantes de la investigación sobre liderazgo educativo. Particularmente, nos centramos en tres grandes dimensiones actuales de la investigación sobre el liderazgo: el liderazgo pedagógico o para el aprendizaje, el liderazgo distribuido y el liderazgo para la justicia social. A su vez, estas dimensiones constituyen el interés principal de cada uno de los tres proyectos “vivos” del Plan Nacional de I+D+i que dirigen respectivamente los autores del artículo. La comprensión actual del liderazgo se aleja de la visión del director como único agente con poder, para adoptar una perspectiva distribuida o compartida. A su vez, se busca un liderazgo pedagógico capaz de incidir en la mejora de los aprendizajes, creando condiciones para que el profesorado pueda hacerlo mejor. Y también, por último, un liderazgo para la justicia social, que asegure una buena educación a todos los alumnos, desde una perspectiva inclusiva y equitativa. Con el propósito de mantener conectadas dichas perspectivas, los autores del artículo han formado recientemente la “Red de Investigación sobre Liderazgo y Mejora Educativa (RILME)”.As most of top-bottom educational reforms have proved very limited impact on school improvement, educational leadership is increasingly perceived as the key factor to promote such improvement, facilitating the conditions that can lead us towards more successful schools. Departing from a review of the current international literature, this paper suggests and discusses three of the relevant focus of the research about educational leadership, including: leadership for learning, distributed leadership, and leadership for social justice. Such dimensions are respectively the core interest of each of the three current research projects (funded by the National R&D&I Plan) led by the authors of the paper. On the one hand, the current understanding of leadership is far from the vision of the principal as the only agent that exerts power and influence in the school and close to a shared o distributed perspective. On the other hand, only instructional leadership will be capable to improve learning, building conditions for teachers to improve their teaching. Finally, schools need a leadership for social justice in order to ensure a good education to all students, from an inclusive and equitable perspective. Bearing in mind the purpose of getting connected such perspectives, the authors of the article have recently launched the “Network of Research on Leadership and School Improvement”

Optimization Of Temperature Field Evolution Simulation During Wet Flat Grinding

We have considered the analytical solutions for heat transfer in wet flat grinding, assuming a linear and a constant heat flux profile, entering into the workpiece. We assume as well a constant heat transfer coefficient for the coolant acting on the workpiece surface. In order to avoid thermal damage, we provide a very fast method for the computation of the maximum temperature, which occurs on the workpiece surface in the stationary regime. We also provide a very rapid method for the numerical evaluation of the transient regime duration (relaxation time). By knowing the location of the maximum temperature and the relaxation time, we have performed an analysis for the computation optimization of the temperature evolution on the workpiece surface. This kind of analysis offers a very interesting simulation tool to avoid thermal damage during the transient regime.Ciencias Experimentale

Freeze desalination by the integration of falling film and block freeze concentration techniques

Block and falling film freeze concentration are two technologies that separate water by freezing,with the potential to desalinate seawater. In this study, the integration of two freeze concentration techniques as an alternative to obtain potable water was analysed. Water with 0.5%–8% NaCl was freeze-concentrated by the falling film technique. The ice from each stage was fractionally thawed to recover the solids retained inPostprint (updated version

cis-Regulatory Requirements for Tissue-Specific Programs of the Circadian Clock

SummaryBackgroundBroadly expressed transcriptions factors (TFs) control tissue-specific programs of gene expression through interactions with local TF networks. A prime example is the circadian clock: although the conserved TFs CLOCK (CLK) and CYCLE (CYC) control a transcriptional circuit throughout animal bodies, rhythms in behavior and physiology are generated tissue specifically. Yet, how CLK and CYC determine tissue-specific clock programs has remained unclear.ResultsHere, we use a functional genomics approach to determine the cis-regulatory requirements for clock specificity. We first determine CLK and CYC genome-wide binding targets in heads and bodies by ChIP-seq and show that they have distinct DNA targets in the two tissue contexts. Computational dissection of CLK/CYC context-specific binding sites reveals sequence motifs for putative partner factors, which are predictive for individual binding sites. Among them, we show that the opa and GATA motifs, differentially enriched in head and body binding sites respectively, can be bound by OPA and SERPENT (SRP). They act synergistically with CLK/CYC in the Drosophila feedback loop, suggesting that they help to determine their direct targets and therefore orchestrate tissue-specific clock outputs. In addition, using in vivo transgenic assays, we validate that GATA motifs are required for proper tissue-specific gene expression in the adult fat body, midgut, and Malpighian tubules, revealing a cis-regulatory signature for enhancers of the peripheral circadian clock.ConclusionsOur results reveal how universal clock circuits can regulate tissue-specific rhythms and, more generally, provide insights into the mechanism by which universal TFs can be modulated to drive tissue-specific programs of gene expression

Updating temperature and salinity mean values and trends in the Western Mediterranean: the RADMED project

Postprin

Relativistic Klein-Gordon charge effects by information-theoretic measures

The charge spreading of ground and excited states of Klein-Gordon particles moving in a Coulomb potential is quantitatively analyzed by means of the ordinary moments and the Heisenberg measure as well as by use of the most relevant information-theoretic measures of global (Shannon entropic power) and local (Fisher's information) types. The dependence of these complementary quantities on the nuclear charge Z and the quantum numbers characterizing the physical states is carefully discussed. The comparison of the relativistic Klein-Gordon and non-relativistic Schrodinger values is made. The non-relativistic limits at large principal quantum number n and for small values of Z are also reached.Comment: Accepted in New Journal of Physic