Hacia el desarrollo de una competencia sociocultural en aprendientes de francés

Al aprender una lengua extranjera, una competencia lingüística es indispensable para comprender y producir oraciones. Sin embargo, para lograr un desempeño óptimo en situaciones de la vida cotidiana ajenas a las de nuestra cultura materna no basta con conocer las reglas gramaticales sino también los patrones sociales y culturales únicos de cada cultura

The Non-Mesonic Weak Decay of Double-Lambda Hypernuclei: A Microscopic Approach

The non--mesonic weak decay of double--$\Lambda$ hypernuclei is studied within a microscopic diagrammatic approach. Besides the nucleon--induced mechanism, $\Lambda N\to nN$, widely studied in single--$\Lambda$ hypernuclei, additional hyperon--induced mechanisms, $\Lambda \Lambda\to \Lambda n$, $\Lambda \Lambda\to \Sigma^0 n$ and $\Lambda \Lambda\to \Sigma^-p$, are accessible in double--$\Lambda$ hypernuclei and are investigated here. As in previous works on single--$\Lambda$ hypernuclei, we adopt a nuclear matter formalism extended to finite nuclei via the local density approximation and a one--meson exchange weak transition potential (including the ground state pseudoscalar and vector octets mesons) supplemented by correlated and uncorrelated two--pion--exchange contributions. The weak decay rates are evaluated for hypernuclei in the region of the experimentally accessible light hypernuclei $^{10}_{\Lambda\Lambda}$Be and $^{13}_{\Lambda\Lambda}$B. Our predictions are compared with a few previous evaluations. The rate for the $\Lambda \Lambda\to \Lambda n$ decay is dominated by $K$--, $K^*$-- and $\eta$--exchange and turns out to be about 2.5\% of the free $\Lambda$ decay rate, $\Gamma_{\Lambda}^{\rm free}$, while the total rate for the $\Lambda \Lambda\to \Sigma^0 n$ and $\Lambda \Lambda\to \Sigma^- p$ decays, dominated by $\pi$--exchange, amounts to about 0.25\% of $\Gamma_{\Lambda}^{\rm free}$. The experimental measurement of these decays would be essential for the beginning of a systematic study of the non--mesonic decay of strangeness $-2$ hypernuclei. This field of research could also shed light on the possible existence and nature of the $H$--dibaryon.Comment: 17 pages, 2 figure

Optimal Control Realizations of Lagrangian Systems with Symmetry

A new relation among a class of optimal control systems and Lagrangian systems with symmetry is discussed. It will be shown that a family of solutions of optimal control systems whose control equation are obtained by means of a group action are in correspondence with the solutions of a mechanical Lagrangian system with symmetry. This result also explains the equivalence of the class of Lagrangian systems with symmetry and optimal control problems discussed in \cite{Bl98}, \cite{Bl00}. The explicit realization of this correspondence is obtained by a judicious use of Clebsch variables and Lin constraints, a technique originally developed to provide simple realizations of Lagrangian systems with symmetry. It is noteworthy to point out that this correspondence exchanges the role of state and control variables for control systems with the configuration and Clebsch variables for the corresponding Lagrangian system. These results are illustrated with various simple applications

Lesson study as a tool for rebuilding teachers' practical thinking: a bridge between espoused theories and theories-in-use

This Lesson Study forms part of the research work carried out by the Spanish team, in order to analyse the potential of this professional teacher development methodology for the reconstruction of teachers' practical thinking. It is a qualitative research process which involves the monitoring of seven infant school teachers during two school cycles. The teachers developed a Lesson Study over this period, with a practical thinking case study being carried out both before and after. This paper focuses on the Lesson Study case study. The Lesson Study was developed independently by the group of teachers, who were advised throughout by the undersigned researchers. At the same time, the researchers carried out a case study focusing on the Lesson Study being developed by the teachers. Findings/Conclusions: - From the start of the Lesson Study, we can find evidence of changes in the practical thinking of the teachers involved, which led to immediate changes in their classroom practice. - The development of the Lesson Study brought about significant reflection with regards to the Infant Education curriculum, in some cases resulting in substantial modification to the way it is implemented in their different classrooms. - The teachers pointed out the value of cooperative work on several different occasions. - They also emphasised the high level of learning they achieved by observing how their colleagues developed the lesson designed by the group using different strategies and data collection instruments, such as documentation inspired by the Reggio Emilia approach, when reflecting on their own practice. On the whole, we can state that the cooperative design work of this lesson showed the contrast between the espoused theories of the participants and their theories-in-use, conditioned fundamentally by their work contexts and previous experience. Lesson Study is a way to bring these two poles closer together, enriching teachers with strategies to help detect contradictions in their practice and to resolve them and feel more comfortable with what they do.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

Funciones que cumple el cuaderno resolutor al abordar una situación problema

Este artículo está especialmente elaborado para docentes y/o alumnos para profesores que deseen trabajar en la búsqueda de la solución de problemas a partir de la metodología del cuaderno resolutor, partiendo de la experiencia en el aula con un grupo de estudiantes donde se lleva a cabo una situación – problema (lugares geométricos), haciendo énfasis en la resolución de problemas que se plantea desde la teoría y contrastando con la experiencia propia que se tiene para llegar a la solución del problema.se formulen preguntas: ¿Qué es un cuaderno resolutor?, ¿Cómo lo manejan los estudiantes?, ¿Qué instrucciones se le daban para escribir en el cuaderno?, clarifique el objetivo, defina y ejecuta el plan de acción y finalmente se evalúe la solución

Perceveid Social Support in middle school students

Research on school climate has among its purposes to contribute to improving the quality of education, one of the main challenges of the Mexican educational system, particularly at the level of basic education. Our aim was to explore the relationships between the dimensions of school climate of perceived social the support teacher-student, support student-student and opportunities for autonomy and academic performance. The study was non-experimental and correlational. The sample consisted of 325 students from a middle school in northeastern Mexico, with a mean age of 13.4 years who responded to a scale of perceived school climate. The results show that students perceive great teacher support associated with student-student support and opportunities for autonomy. In addition, we found that academic achievement related to teacher support and opportunities for autonomy. These data are consistent with the country´s educational policy, which emphasizes the teacher´s role as facilitator of student learning to improve learning outcomes and the quality of education.Fil: Rodriguez, María Concepción. Universidad Autónoma de Nuevo León; MéxicoFil: Vivas, Jorge Ricardo. Universidad Nacional de Mar del Plata. Facultad de Psicología. Centro de Investigación en Procesos Básicos, Metodologías y Educación; ArgentinaFil: Comesaña, Ana. Universidad Nacional de Mar del Plata. Facultad de Psicología. Centro de Investigación en Procesos Básicos, Metodologías y Educación; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; ArgentinaFil: Ramirez, Laura Minerva. Universidad Autónoma de Nuevo León; MéxicoFil: Peña, José Armando. Universidad Autónoma de Nuevo León; Méxic

Constraints on stellar convection from multi-colour photometry of Delta Scuti stars

In Delta Scuti star models, the calculated amplitude ratios and phase differences for multi-colour photometry exhibit a strong dependence on convection. These observables are tools for determination of the spherical harmonic degree of the excited modes. The dependence on convection enters through the complex parameter f, which describes bolometric flux perturbation. We present a method of simultaneous determination of f and spherical harmonic degree from multi-colour data and apply it to three Delta Scuti stars. The method indeed works. Determination of the degree appears unique and the inferred f's are sufficiently accurate to yield a useful constraint on models of stellar convection. Furthermore, the method helps to refine stellar parameters, especially if the identified mode is radial.Comment: 9 pages, 12 figures, to appear in Astronomy and Astrophysic

Cytokines and Maternal Omega-3 LCPUFAs Supplementation

Daily supplementation of maternal diet during pregnancy and lactation with a fish oil-enriched dairy product increases the percentage of DHA and other omega-3 (ω-3) long-chain polyunsaturated fatty acids (LCPUFAs) in mothers (placenta, plasma, erythrocyte membranes, and breast milk) and children (plasma and erythrocyte membranes). This supplementation during critical periods such as pregnancy, lactation, and early development of a newborn may influence the levels of certain inflammatory cytokines, reducing pro-inflammatory cytokines and promoting an anti-inflammatory “environment”. In pregnant women who have not received any supplement of omega-3 LCPUFAs, IL-6 plasma levels are higher, while TNF-alpha plasma levels are also higher in their breastfed infant at birth and 2 months thereafter. There could be a relationship between docosahexaenoic acid (DHA) and the concentrations of different cytokines

Trend in statistical research productivity by journal publications over the period 1985-1997

This work presents a descriptive analysis of the dynamic evolution of statistical research productivity over the period 1985-1997. Research productivity is measured by using the volume of articles published in a set of journals with high impact index. We analyze the productivity trends in the thirty most productive countries and in the twenty top institutions of United States, Europe and the rest of the world