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Se plantea la necesidad de mejorar el libro de texto y realizar determinadas modificaciones que se resultan beneficiosas. Se proponen algunas consideraciones a tener en cuenta para mejorar el libro de texto, tales como: la presentación, es decir, que las fotografías estén bien escogidas y bien reproducidas; las redacciones de los vocabularios deben ser más interesantes y más divertidas; y que las narraciones, historias o cuentos despierten el interés de los alumnos.

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Se analiza el concepto de la magnitud escalar. Se parte de una definición general de magnitud como una cantidad que puede aumentar y disminuir. Esta definición apoya el concepto de magnitud en el de cantidad. Define la cantidad como todo aquello que se puede medir, con lo que se hace necesario el concepto de medida para definir el de magnitud. Se señala que así lo que se consigue es caer en un círculo vicioso, que conlleva que toda definición deba ser completada con otra. Pero aún así se profundiza aún más en las anteriores definiciones para, a continuación, fundamentar matemáticamente una definición de magnitud escalar. Se toman en consideración relaciones matemáticas como la relación de igualdad en un conjunto, la definición de la suma en un conjunto cualquiera, la definición de un semigrupo aditivo, o de los conjuntos totalmente ordenados, aquellos en los que entre elementos existe una relación, con unas propiedades determinadas. Posteriormente se da una definición de magnitud como un semigrupo aditivo abeliano con una ordenación arquimediana. También se señala que los elementos de una magnitud se llaman cantidades. Por último se trata la cuestión de la medida de una magnitud escalar.

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Convocatoria de Premios Nacionales de Investigación e Innovación Educativa 2006, modalidad innovación educativa, mención honorífica

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Analizar desde una perspectiva dinámica la evolución de los alumnos que acceden a las Escuelas Universitarias de Magisterio a lo largo de la década de 1980, así como las diversas salidas profesionales en que se embarcan una vez finalizados sus estudios. Reconstruir el pasado social y académico de estos ex-alumnos a partir de su actual situación en los mercados laborales. Conocer las fluctuaciones habidas en las clientelas de las Escuelas de Magisterio en un periodo de tiempo significativo, y poner en relación la socialización profesional que llevan a cabo con las diversas oportunidades sociolaborales. 357 ex-alumnos que estudiaron Magisterio en Madrid, Toledo, Valencia y Oviedo. Se subdivide en tres estratos cronológicos consecutivos que comprenden a 3 cohortes (promociones) situadas al principio, a mitad y a finales de la década de los 80: 1979-82, 1983-86 y 1987-90. La investigación se centra en 3 grandes bloques temáticos: 1. Una revisión de la literatura sociológica sobre el Magisterio. 2. Un análisis, a partir de los datos empíricos obtenidos mediante una encuesta y unas entrevistas, de la evolución del alumnado que ha ido accediendo a las Escuelas Universitarias de Magisterio a lo largo de la década de los ochenta. Los resultados obtenidos se cruzan con las variables promoción y sexo. 3. Una vez dispuesto el marco global de reclutamiento, se estudia el tránsito desde la socialización académica a la vida laboral. 1. A lo largo de la década de los 80, las diversas cohortes se caracterizan por unos orígenes sociales de estratos medios bajos y bajos, así como por unas trayectorias académicas modestas. No obstante, la promoción intermedia (1983-87) presenta índices algo más altos en ambos aspectos. Asimismo la tendencia a la feminización se acentúa en la última promoción. 2. Las credenciales académicas juegan un papel significativo en el destino de los flujos que salen del sistema educativo y en la clasificación del mercado laboral. A un mejor rendimiento en la formación inicial le corresponden mayores posibilidades de acceso a la docencia. 3. En la obtención de empleo, mientras en la enseñanza pública operan los criterios universalistas, en la privada lo hacen los particularistas. 4. A la enseñanza, se dedican titulados de extracción social más elevada y más religiosos. A otras actividades laborales, van titulados de procedencia más urbana y más laicos. 5. Los titulados en paro se nutren básicamente de jóvenes que buscan su primer empleo y de mujeres casadas mayores de 35 años. 6. La enseñanza privada sirve de formación profesional a la enseñanza pública..

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Aproximación a los hábitos de consumo de la población infantil escolarizada de 0-6 años, con atención preferente sobre los productos de baja calidad nutricional (BACAN), más conocidos como golosinas.Elaborar un programa de intervención dirigido a los distintos sectores de la comunidad educativa: centros, familias y niños, cuyo objetivo es reducir el consumo abusivo de productos de baja calidad nutricional. Muestra de 492 padres de niños matriculados en primer ciclo de los Centros de Educación Infantil, dependientes de la CARM y de segundo ciclo de EI de centros dependientes del MEC. Recogida de información mediante la aplicación de un cuestionario a los padres-madres. Análisis de datos. Elaboración de un programa de intervención en centros escolares. Cuestionario sobre consumo, de elaboración propia. Correlación entre variables. Estadísticos: Chi cuadrado de Pearson y de Likelihood Ratio. El consumo de productos BACAN no es homogéneo. Se diversifica y aumenta con la edad, excepción hecha con los fritos industriales cuyo consumo aparece a las edades más tempranas. La mayoría de las familias sitúan el consumo de sus hijos entre una y tres unidades de estos productos. Se ha constatado que los padres proporcionan estos productos a los hijos a pesar de estar informados de su perjuicio sobre la salud.

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Resumen basado en el de la publicaci??n

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The mortality (7 and 14 d), weight change (7 and 14 d), and metal uptake of Eisenia fetida (Savigny, 1826) kept in Pb(NO3)(2)-treated Kettering loam soil in single- and multiple-occupancy (10 earthworms) test containers were determined. The number of earthworms to dry mass (g) ratio of soil was 1:50 in both sets of test containers. Lead concentrations were in the nominal range of 0 to 10,000 mg Pb/kg soil (mg/kg hereafter). Levels of mortality at a given concentration were statistically identical between the single- and multiple-occupancy tests, except at 1,800 mg/kg, at which significantly (p less than or equal to 0.05) more mortality occurred in the multiple-occupancy tests. Death of individual earthworms in the multiple-occupancy tests did not trigger death of the other earthworms in that soil. The LC50 values (concentration statistically likely to kill 50% of the population) were identical between the multiple- and single-occupancy soils: 2,662 mg/kg (2,598-2,984, 7 d) and 2,589 mg/kg (2,251-3,013, 14 d) for the multiple-occupancy soils and 2,827 mg/kg (2,443-3,168, both 7 and 14 d) for the single-occupancy soils (values in brackets represent the 95% confidence intervals). Data were insufficient to calculate the concentration statistically likely to reduce individual earthworm mass by 50% (EC50), but after 14 d, the decrease in earthworm weight in the 1,800 and 3,000 mg/kg tests was significantly greater in the multiple- than in the single-occupancy soils. At 1,000, 1,800, and 3,000 mg/kg tests, earthworm Pb tissue concentration was significantly (p less than or equal to 0.05) greater in earthworms from the multiple-occupancy soils. The presence of earthworms increased the NH3 content of the soil; earthworm mortality increased NH3 concentrations further but not to toxic levels.

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To examine the basis of emotional changes to the voice, physiological and electroglottal measures were combined with acoustic speech analysis of 30 men performing a computer task in which they lost or gained points under two levels of difficulty. Predictions of the main effects of difficulty and reward on the voice were not borne out by the data. Instead, vocal changes depended largely on interactions between gain versus loss and difficulty. The rate at which the vocal folds open and close (fundamental frequency; f0) was higher for loss than for gain when difficulty was high, but not when difficulty was low. Electroglottal measures revealed that f0 changes corresponded to shorter glottal open times for the loss conditions. Longer closed and shorter open phases were consistent with raised laryngeal tension in difficult loss conditions. Similarly, skin conductance indicated higher sympathetic arousal in loss than gain conditions, particularly when difficulty was high. The results provide evidence of the physiological basis of affective vocal responses, confirming the utility of measuring physiology and voice in the study of emotion.

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We study ordinary nonlinear singular differential equations which arise from steady conservation laws with source terms. An example of steady conservation laws which leads to those scalar equations is the Saint–Venant equations. The numerical solution of these scalar equations is sought by using the ideas of upwinding and discretisation of source terms. Both the Engquist–Osher scheme and the Roe scheme are used with different strategies for discretising the source terms.

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An annually laminated, uranium-series dated, Holocene stalagmite from southeast Ethiopia has been analysed for growth rate and δ13C and δ18O variations at annual to biennial resolution, in order to provide the first long duration proxy record of decadal-scale rainfall variability in this climatically sensitive region. Our study site (10°N) is climatically influenced by both summer (June—August) and spring (March—May) rainfall caused by the annual movement of the Inter-Tropical Convergence Zone (ITCZ) and modulated by large-scale anomalies in the atmospheric circulation and in ocean temperatures. Here we show that stalagmite growth, episodic throughout the last 7800 years, demonstrates decadal-scale (8—25 yr) variability in both growth rate and δ 18O. A hydrological model was employed and indicates that this decadal variability is due to variations in the relative amounts of rainfall in the two rain seasons. Our record, unique in its combination of length (a total of ~1000 years), annual chronology and high resolution δ18O, shows for the first time that such decadal-scale variability in rainfall in this region has occurred through the Holocene, which implies persistent decadal-scale variability for the large-scale atmospheric and oceanic driving factors.

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This chapter describes the present status and future prospects for transgenic (genetically modified) crops. It concentrates on the most recent data obtained from patent databases and field trial applications, as well as the usual scientific literature. By these means, it is possible to obtain a useful perspective into future commercial products and international trends. The various research areas are subdivided on the basis of those associated with input (agronomic) traits and those concerned with output (e.g., food quality) characteristics. Among the former group are new methods of improving stress resistance, and among the latter are many examples of producing pharmaceutical compounds in plants.

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Toll-like receptors (TLR) recognize microbial and viral patterns and activate dendritic cells (DC). TLR distribution among human DC subsets is heterogeneous: plasmacytoid DC (PDC) express TLR1, 7 and 9, while other DC types do not express TLR9 but express other TLR. Here, we report that mRNA for most TLR is expressed at similar levels by murine splenic DC sub-types, including PDC, but that TLR3 is preferentially expressed by CD8α+ DC while TLR5 and TLR7 are selectively absent from the same subset. Consistent with the latter, TLR7 ligand activates CD8α– DC and PDC, but not CD8α+ DC as measured by survival ex vivo, up-regulation of surface markers and production of IL-12p40. These data suggest that the dichotomy in TLR expression between plasmacytoid and non-plasmacytoid DC is not conserved between species. However, lack of TLR7 expression could restrict the involvement of CD8α+ DC in recognition of certain mouse pathogens.

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A study was conducted to estimate variation among laboratories and between manual and automated techniques of measuring pressure on the resulting gas production profiles (GPP). Eight feeds (molassed sugarbeet feed, grass silage, maize silage, soyabean hulls, maize gluten feed, whole crop wheat silage, wheat, glucose) were milled to pass a I mm screen and sent to three laboratories (ADAS Nutritional Sciences Research Unit, UK; Institute of Grassland and Environmental Research (IGER), UK; Wageningen University, The Netherlands). Each laboratory measured GPP over 144 h using standardised procedures with manual pressure transducers (MPT) and automated pressure systems (APS). The APS at ADAS used a pressure transducer and bottles in a shaking water bath, while the APS at Wageningen and IGER used a pressure sensor and bottles held in a stationary rack. Apparent dry matter degradability (ADDM) was estimated at the end of the incubation. GPP were fitted to a modified Michaelis-Menten model assuming a single phase of gas production, and GPP were described in terms of the asymptotic volume of gas produced (A), the time to half A (B), the time of maximum gas production rate (t(RM) (gas)) and maximum gas production rate (R-M (gas)). There were effects (P<0.001) of substrate on all parameters. However, MPT produced more (P<0.001) gas, but with longer (P<0.001) B and t(RM gas) (P<0.05) and lower (P<0.001) R-M gas compared to APS. There was no difference between apparatus in ADDM estimates. Interactions occurred between substrate and apparatus, substrate and laboratory, and laboratory and apparatus. However, when mean values for MPT were regressed from the individual laboratories, relationships were good (i.e., adjusted R-2 = 0.827 or higher). Good relationships were also observed with APS, although they were weaker than for MPT (i.e., adjusted R-2 = 0.723 or higher). The relationships between mean MPT and mean APS data were also good (i.e., adjusted R 2 = 0. 844 or higher). Data suggest that, although laboratory and method of measuring pressure are sources of variation in GPP estimation, it should be possible using appropriate mathematical models to standardise data among laboratories so that data from one laboratory could be extrapolated to others. This would allow development of a database of GPP data from many diverse feeds. (c) 2005 Published by Elsevier B.V.