Una función de producción subjetiva para trigo en la Región Pampeana (Argentina)

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Caracterización de montes del centro norte de Entre Ríos y propuesta de manejo silvopastoril

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Transmisión por semilla, epidemiología y control de la mancha en red de la cebada (Dreschslera teres)

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Comunidad virtual de discurso profasional geométrico: contribuciones de un proceso interactivo docente por internet

La naturaleza del pensamiento de los profesores es una área de considerable interés y la atención hacia la relevancia de la geometría como un importante componente formativo es un hecho en los planteamientos interesados en la formación inicial y continuada del profesorado. En el ámbito de la investigación cualitativa, presentaremos las contribuciones de un entorno virtual para el desarrollo crítico del contenido del conocimiento profesional del profesor de matemática. Específicamente, analizar un proceso teleinteractivo docente a partir de situaciones de enseñanza-aprendizaje en geometría (para alumnos con 11-14 años). La importancia del proceso teleinteractivo para el desarrollo de habilidades metacognitivas en los profesores es un hecho destacable en las conclusiones de la investigación.

Investigação em formação conceitual: o conhecimento de alunos do ensino médio sobre polígonos

This study is part of the area of research in Psychology of Mathematics Education that investigates, among other things, knowledge relating to the formation of mathematical concepts. The objective was to investigate the conceptual knowledge of polygons of 76 high school students in terms of defining attributes and examples and non-examples. The instruments for collecting data was a test with two questions about polygons, defining attributes of a test and a test of examples and non-examples, based on the theory of Klausmeier and Goodwin (1977) on formation of concepts. The results showed that participants of the survey had difficulties in identifying defining attributes of polygons and non-discriminating examples of examples, showing the formation of this concept to the level of identity.

Humans-with-Media en la producción de conocimiento matemático. El caso de Geogebra

Este documento se usa el constructo teórico Humans-with-Media para analizar una situación construida con el software Geogebra. La situación muestra un posible entendimiento de la función derivada a partir del reconocimiento de la “función tasa de variación”.

Representaciones sociales acerca del concepto matemática

La presente investigación centra la atención en el contexto de la Teoría de Representaciones Sociales propuesta por Moscovici en 1961. Apoyándonos en esta teoría, realizamos un estudio y análisis de las Representaciones Sociales acerca del concepto “Matemática”, trabajo que tiene por objetivo identificar, analizar e interpretar algunos de los elementos que forman parte del sistema central, mediante un cuestionario aplicado a 29 estudiantes de preparatoria que forman parte del Instituto de Ciencia y Tecnología del Distrito Federal.

El método de Descartes para trazar normales a curvas

El trabajo que hemos desarrollado en este artículo es un estudio de un método histórico desarrollado por Descartes para calcular la recta normal a una curva, y que puede ser aprovechado para calcular derivadas puntuales y generales de funciones. El método, requiere de la resolución de ecuaciones algebraicas y transcendentes, que en principio pueden ser complicadas (por eso ha caído en el olvido), pero que permite introducir en el aula una gran cantidad de aspectos docentes. Además, la idea en la que se fundamenta el método de Descartes puede ser aprovechada para calcular la distancia de un punto a una recta o un plano.

The in-service teacher trainer: profile, career path and duties

This article is the result of a doctoral thesis that aims to understand the reality of teacher trainers at a given moment, when their professional role changes from being a managing training advisor to a role that is more centred on process counselling. Using in-depth interviews, we defined the personal and professional profile of training counsellors in the Balearic Islands, their career path, the process for their inclusion in Teacher Centres (CEP) and, finally, the duties and skills that they perform as teacher trainers. The data that has been collected shows the coexistence of different professional roles in the group of education advisors. Moreover, it also indicates a lack of definition of the profile needed to access an advisor's position. There are indeed some coincidences determining the access route to such a position when it comes to the teaching profession since their leadership qualities and group dynamics expertise are a common indicator in most cases. The research also shows that they are subjected not only to a wide range of roles and tasks but also to a vast array of competences required to tackle the education advisor's tasks.

Instrumentos de evaluación utilizados en la formación inicial del profesorado y su coherencia para el desarrollo de competencias profesionales en los estudiantes: visión del alumnado, egresados y profesorado

El objetivo de este trabajo es analizar la frecuencia con que se utilizan diferentes instrumentos y procedimientos de evaluación desde el punto de vista del profesorado, del alumnado y de los egresados en la formación inicial de maestros y profesores especialistas en Educación Física, así como el grado de coherencia –relación- percibido por cada uno de esos grupos implicados entre dichos instrumentos y procedimientos de evaluación y el desarrollo de las competencias profesionales que se pretende adquieran los estudiantes. La muestra objeto de estudio está compuesta por 199 alumnos, 67 egresados y 53 profesores de las titulaciones de Magisterio (especialidad de Educación Física) y Ciencias de la Actividad Física y el Deporte de las universidades de Valladolid, Salamanca y León. Los resultados muestran una clara discrepancia entre los distintos grupos analizados, tanto en lo referido al tipo de instrumentos de evaluación utilizados, como en la valoración del grado de coherencia entre estos y el desarrollo de las competencias profesionales de los futuros maestros.

Incidence of glaucoma in patients with uveitis

Purpose: To evaluate the incidence of glaucoma and elevation of intraocular pressure (IOP) in patients with inflammatory eye disease. Methods: Retrospective review of medical records of 391 consecutive patients with uveitis attending a uveitis clinic of an academic Department of Ophthalmology from January 1999 to August 2002. Demographic, ocular and systemic variables were recorded. The diagnosis and treatment of uveitis were recorded. Uveitis was classified according to standard anatomic, etiological and clinical criteria. "Glaucoma" was defined as elevated IOP (>21 mm Hg) or glaucomatous optic nerve damage requiring medical and/or surgical anti-glaucoma treatment. Kaplan-Maier analysis and log-rank tests were used to evaluate and compare the incidence of glaucoma. Results: The incidence of glaucoma as defined above at 3 and 12 months after acute uveitis was 7.6%. In patients with chronic uveitis (n = 337), the incidence of glaucoma at 1 and 5 years was 6.5% and 11.1%, respectively. There was no statistically significant difference in the incidence of glaucoma between different types of uveitis, idiopathic versus non-idiopathic, and among anterior, intermediate, posterior and panuveitis. Visual loss occurred more frequently in patients with glaucoma than in patients without glaucoma. Conclusion: In patients with chronic inflammatory eye disease, the presence of glaucoma was associated with an increasing risk of visual loss. The incidence of glaucoma increased with time and was similar among the different types of uveitis.

The PREDICTS database: a global database of how local terrestrial biodiversity responds to human impacts

Biodiversity continues to decline in the face of increasing anthropogenic pressures such as habitat destruction, exploitation, pollution and introduction of alien species. Existing global databases of species' threat status or population time series are dominated by charismatic species. The collation of datasets with broad taxonomic and biogeographic extents, and that support computation of a range of biodiversity indicators, is necessary to enable better understanding of historical declines and to project - and avert - future declines. We describe and assess a new database of more than 1.6 million samples from 78 countries representing over 28,000 species, collated from existing spatial comparisons of local-scale biodiversity exposed to different intensities and types of anthropogenic pressures, from terrestrial sites around the world. The database contains measurements taken in 208 (of 814) ecoregions, 13 (of 14) biomes, 25 (of 35) biodiversity hotspots and 16 (of 17) megadiverse countries. The database contains more than 1% of the total number of all species described, and more than 1% of the described species within many taxonomic groups - including flowering plants, gymnosperms, birds, mammals, reptiles, amphibians, beetles, lepidopterans and hymenopterans. The dataset, which is still being added to, is therefore already considerably larger and more representative than those used by previous quantitative models of biodiversity trends and responses. The database is being assembled as part of the PREDICTS project (Projecting Responses of Ecological Diversity In Changing Terrestrial Systems - http://www.predicts.org.uk). We make site-level summary data available alongside this article. The full database will be publicly available in 2015.

Institutional Frameworks and Structural Factors Relating to Educational Access Across Europe

In this article institutional and structural factors relating to access to education are assessed. First, the macro frameworks of institutional regulation that exert influence on the educational trajectories of young Europeans are demonstrated. Based on different aspects of these frameworks and drawing from extant research, the article presents a typology of education systems that provide varying levels of access to and accessibility of education in Finland, France, Germany, Italy, Poland, the Netherlands, Slovenia, and the United Kingdom. Second, using survey data (N = 6,366) it analyzes the impact of gender and parental education on young people’s educational aspirations and early labor-market entry across the countries.

CSI 2264: Simultaneous Optical and Infrared Light Curves of Young Disk-bearing Stars in NGC 2264 with CoRoT and Spitzer—Evidence for Multiple Origins of Variability

We present the Coordinated Synoptic Investigation of NGC 2264, a continuous 30 day multi-wavelength photometric monitoring campaign on more than 1000 young cluster members using 16 telescopes. The unprecedented combination of multi-wavelength, high-precision, high-cadence, and long-duration data opens a new window into the time domain behavior of young stellar objects. Here we provide an overview of the observations, focusing on results from Spitzer and CoRoT. The highlight of this work is detailed analysis of 162 classical T Tauri stars for which we can probe optical and mid-infrared flux variations to 1% amplitudes and sub-hour timescales. We present a morphological variability census and then use metrics of periodicity, stochasticity, and symmetry to statistically separate the light curves into seven distinct classes, which we suggest represent different physical processes and geometric effects. We provide distributions of the characteristic timescales and amplitudes and assess the fractional representation within each class. The largest category (>20%) are optical "dippers" with discrete fading events lasting ~1-5 days. The degree of correlation between the optical and infrared light curves is positive but weak; notably, the independently assigned optical and infrared morphology classes tend to be different for the same object. Assessment of flux variation behavior with respect to (circum)stellar properties reveals correlations of variability parameters with Hα emission and with effective temperature. Overall, our results point to multiple origins of young star variability, including circumstellar obscuration events, hot spots on the star and/or disk, accretion bursts, and rapid structural changes in the inner disk. Based on data from the Spitzer and CoRoT missions. The CoRoT space mission was developed and is operated by the French space agency CNES, with participation of ESA's RSSD and Science Programmes, Austria, Belgium, Brazil, Germany, and Spain.