To a dynamic and efficient model of training of the teachers

The current context of education, characterized by major changes and innovations made lately, makes teachers as the key to educational change, have a role that will help prepare students to understand the society in which they operate. In this regard, we develop in this paper several approaches, why educate a person in childhood and compulsory education, how to teach content so that students learn significantly? or what kind of training of teachers should acquire to meet these needs. Issues such as the response will allow us to reflect on the experiences of training and innovation in non-university education

Entre mesura y coquetería: ilustración, prensa y maternidad en la Nueva España

Este artículo examina cómo la Gazeta de México (1784-1809) y el Diario de México (1805-1812) apoyaban la educación de la mujer y su participación en la esfera pública con el objetivo ulterior de que fuera la madre por excelencia. El papel de educadora estuvo, sin embargo, restringido física e intelectualmente por el escrutinio biológico y moral que se hacía de las mujeres en estas publicaciones. La mención de la mujer en estos medios impresos refleja el interés gubernamental de entenderla como la encargada de producir ciudadanos. Sin embargo, su centralidad como madre se contrapone con la forma en que su presencia en la esfera pública fue acogida por los mismos intelectuales que impulsaban su educación pero desdeñaban su desenvolvimiento social

Electrochemical Characterization of Mass Transport at Microelectrode Arrays.

Electrodes with dimensions in the micro- and nano-meter scale can be used as analytical probes in confi ned places such as cells and organelles. Arrays of microelectrodes, particularly disk-shaped electrodes, are now a platform to fabricate electrochemical sensors and multisensors. A useful characteristic of such arrays is that enhancement of the current signal is due to the fact that radial diffusion becomes important as the disk radius gets smaller and steady state currents are attainable in a relatively short time. Because there is no general analytical solution for the current response at MEAs, previous characterization of any micro electrode array at hand is still required. This paper discusses the electrochemical characterization of the mass transport of a reversible electrochemical probe at a commercially available micro-disk electrode array by two commonly used tools for electro analysis, namely: cyclic voltammetry and chronoamperometry. The questions to be addressed are whether clear radial diffusion control can be effectively achieved and the time required for the electrode system to reach steady state. For chronoamperometric experiments, the current response almost achieves steady state in the time range between 0.49 s and 1 s. This is precisely the time bracket in which analytical measurements should be made in order to achieve high sensitivity

Efectos de la implementación de una metodología de aprendizaje basado en proyectos incluyendo componentes de integración curricular en estudiantes de nivel secundario

This report shows how a research process was carried out to determine the perception of students from a private school in Sincelejo – Sucre about complementing their foreign language classes through a methodology based in projects execution. The inclusion of the methodology responds to the necessity of diversifying the regular and traditional classes that, despite the fact of being well directed and showing results, needed variations to make the language teaching process more effective. It was defined a cross sectional study to perform the process, due to the characteristics of the problem and the population. A sample of 28 students out of a total of 110 belonging to 8th, 9th and 10th grades of the school was selected to collect the data through a survey composed by ten agreement – disagreement (Likert scale) type questions. Results showed a positive impact of the application of the methodology and strategies in the students, inviting this way the school English team to continue implementing actions and methods pointing to work through projects.Este reporte muestra cómo un proceso de investigación fue llevado a cabo para determinar la percepción de los estudiantes de un colegio privado en Sincelejo – Sucre acerca de complementar sus clases de idioma extranjero a través de una metodología basada en la ejecución de proyectos. La inclusión de la metodología responde a la necesidad de diversificar las clases normales y tradicionales que, a pesar de ser bien orientadas y mostrar resultados, necesitaban variaciones para hacer del proceso de enseñanza del idioma más efectivo. Se definió un estudio de corte transversal para llevar a cabo el proceso, dadas las características del problema y la población. Se seleccionó una muestra de 28 de una población total de 110 estudiantes pertenecientes a los grados 8°, 9° y 10° del colegio para recolectar los datos a través de una encuesta con preguntas tipo Acuerdo – Desacuerdo (Escala Likert). Los resultados mostraron un impacto positivo de la aplicación de la metodología y las estrategias en los estudiantes, invitando de esta manera al equipo de inglés de la institución a continuar implementando acciones y métodos enfocados al trabajo en proyectos

Electrochemical Characterization of Mass Transport at Microelectrode Arrays

Electrodes with dimensions in the micro- and nano-meter scale can be used as analytical probes in confi ned places such as cells and organelles. Arrays of microelectrodes, particularly disk-shaped electrodes,  are  now  a  platform  to  fabricate  electrochemical  sensors  and  multisensors. A  useful characteristic of such arrays is that enhancement of the current signal is due to the fact that radial diffusion becomes important as the disk radius gets smaller and steady state currents are attainable in a relatively short time. Because there is no general analytical solution for the current response at MEAs, previous characterization of any micro electrode array at hand is still required. This paper discusses the electrochemical characterization of the mass transport of a reversible electrochemical probe at a commercially available micro-disk electrode array by two commonly used tools for electro analysis, namely: cyclic voltammetry and chronoamperometry. The questions to be addressed are whether clear radial diffusion control can be effectively achieved and the time required for the electrode system to reach steady state. For chronoamperometric experiments, the current response almost achieves steady state in the time range between 0.49 s and 1 s. This is precisely the time bracket in which analytical measurements should be made in order to achieve high sensitivity

Porous Titanium for Biomedical Applications: Evaluation of the Conventional Powder Metallurgy Frontier and Space-Holder Technique

Titanium and its alloys are reference materials in biomedical applications because of their desirable properties. However, one of the most important concerns in long-term prostheses is bone resorption as a result of the stress-shielding phenomena. Development of porous titanium for implants with a low Young’s modulus has accomplished increasing scientific and technological attention. The aim of this study is to evaluate the viability, industrial implementation and potential technology transfer of different powder-metallurgy techniques to obtain porous titanium with stiffness values similar to that exhibited by cortical bone. Porous samples of commercial pure titanium grade-4 were obtained by following both conventional powder metallurgy (PM) and space-holder technique. The conventional PM frontier (Loose-Sintering) was evaluated. Additionally, the technical feasibility of two different space holders (NH4HCO3 and NaCl) was investigated. The microstructural and mechanical properties were assessed. Furthermore, the mechanical properties of titanium porous structures with porosities of 40% were studied by Finite Element Method (FEM) and compared with the experimental results. Some important findings are: (i) the optimal parameters for processing routes used to obtain low Young’s modulus values, retaining suitable mechanical strength; (ii) better mechanical response was obtained by using NH4HCO3 as space holder; and (iii) Ti matrix hardening when the interconnected porosity was 36–45% of total porosity. Finally, the advantages and limitations of the PM techniques employed, towards an industrial implementation, were discussed.Ministry of Economy and Competitiveness of Spain Grant MAT2015-71284-PJunta de Andalucía Grant P12-TEP-1401Comisión Nacional de Investigación, Científica y Tecnológica (CONICYT) of the Chilean government project FONDECYT 1116086

La expresión oral y escrita como proceso clave en el aprendizaje de las ciencias

En este trabajo abordamos la influencia que para el aprendizaje eficiente de las ciencias en la Educación Primaria, puede tener el proceso de comunicación centrado en una correcta expresión oral y escrita por parte del alumnado, pues es un contenido básico para avanzar en el resto de contenidos de las ciencias. Para este fin, consideramos necesario una enseñanza integrada de las diversas áreas de conocimiento de Primaria y con estrategias metodológicas fundamentadas en un enfoque constructivista. Se describen los instrumentos de exploración utilizados y se da respuesta a cuestiones clave como ¿qué hemos encontrado?, ¿qué valoración hacemos? y, finalmente, qué conclusiones obtenemos y qué proponemos cómo líneas de actuación relacionadas con el aprendizaje de este proceso de comunicación

A Radial Velocity Study of the Intermediate Polar EX Hydrae

A study on the intermediate polar EX Hya is presented, based on simultaneous photometry and high dispersion spectroscopic observations, during four consecutive nights. The strong photometric modulation related to with the 67-min spin period of the primary star is clearly present, as well as the narrow eclipses associated to the orbital modulation. Since our eclipse timings have been obtained almost 91,000 cycles since the last reported observations, we present new linear ephemeris, although we cannot rule out a sinusoidal variation suggested by previous authors. The system mainly shows double-peaked H$\alpha$, H$\beta$ and HeI $\lambda$5876 \AA emission lines. From the profile of the H$\alpha$ line, we find two components; one with a steep rise and velocities not larger than $\sim$1000 km s$^{-1}$ and another broader component extending up to $\sim$2000 km s$^{-1}$, which we interpret as coming mainly from the inner disc. A strong and variable hotspot is found and a stream-like structure is seen at times. We show that the best solution correspond to $K_1 = 58 \pm 5$ km s$^{-1}$ from H$\alpha$, from the two emission components, which are both in phase with the orbital modulation. We remark on a peculiar effect in the radial velocity curve around phase zero, which could be interpreted as a Rositter-MacLaughlin-like effect, which has been taken into account before deriving $K_1$. This value is compatible with the values found in high-resolution both in the ultraviolet and X-ray. We find: $M_{1} = 0.78 \pm 0.03$ M$_{\odot}$, $M_{2} = 0.10 \pm 0.02$ M$_{\odot}$ and $a = 0.67 \pm 0.01$ R$_{\odot}$. Doppler Tomography has been applied, to construct six Doppler tomograms for single orbital cycles spanning the four days of observations to support our conclusions. Our results indicate that EX Hya has a well formed disc and that the magnetosphere should extend only to about $3.75\,R_{\rm{WD}}$.Comment: 16 pages, 14 figures, accepted for publication in MNRA