Motivaci??n y cambio conceptual : implicaciones para el aprendizaje y la ense??anza de las Ciencias Naturales, la Historia y la ??tica en la ESO

Evaluar la influencia del contenido de la tarea en el proceso de cambio conceptual, utiliz??ndose como estrategia la presentaci??n de datos an??malos o conflictivos; evaluar la influencia que el estilo epist??mico de los alumnos, concretamente su grado de relativismo, evaluado a trav??s de su capacidad para reconocer y reconciliar posturas diferentes, tiene en diferentes dominios de conocimiento en el proceos de cambio conceptual; estudiar la influencia variables motivacionales en el proceso de cambio conceptual; obtener las implicaciones instruccionales para el aprendizaje y la ense??anza de las Ciencias Sociales y Naturales que se derivan de los estudios llevados a cabo. Se plantearon las siguientes hip??tesis: se lograr?? menor nivel de cambio en la tarea en la que las creencias-explicaciones de los sujetos est??n m??s arraigadas, esto es, en las que los sujetos muestren un posicionamiento m??s fuerte hacia una u otra versi??n, independientemente del contenido de la tarea (cotidiano, ??tico, hist??rico o cient??fico); no habr?? diferencias significativas en el grado de cambio alcanzado en las tareas cotidianas y ??ticas frente a las hist??ricas o frente a las cient??ficas. 669 estudiantes de ESO, siendo 302 alumnos procedentes de diversos colegios e institutos p??blicos de Madrid de primero de ESO y un grupo de cuarto de ESO compuesto por 367 estudiantes. Se han realizado tres estudios. En el primero, se ha estudiado la influencia del contenido de la tarea y del grado de arraigo de las creencias de los alumnos en el grado de cambio que han logrado los estudiantes. Se estudiaron cuatro dominios: historia, ciencias naturales, ??tica y vida cotidiana. En el segundo estudio se ha evaluado el grado de relativismo cognitivo de los sujetos participantes en el estudio, teniendo en cuenta: reconocimiento de la contradicci??n en conflicto entre dos versiones alternativas, identificaci??n de versiones y capacidad de reconciliaci??n de versiones contrapuestas. En el tercer estudio se evalu?? el patr??n motivacional. Se tuvieron en cuenta variables motivacionales (inter??s por la tarea, inter??s en la materia y patr??n motivacional). Tablas, gr??ficos. Los resultados obtenidos indican que el posicionamiento inicial de los sujetos en las tareas determina en buena medida el grado de cambio. Si suposicionamiento es claro, el porcentaje de cambio es inferior. Las tareas en las que el posicionamiento de los sujetos ha sido mayor y por tanto, mayor tambi??n el grado de arraigo de sus creencias han sido las dos de Etica, seguida de las de Historia. El porcentaje medio de cambio entre la respuesta inicial y la final fue de un 19,32 por cien , lo que sugiere que la presentaci??n de versiones contradictorias puede ser una estrategia did??ctica que trabajada en el aula permitir??a identificar el posicionamiento inicial de los estudiantes y promover los primeros pasos del proceso de cambio conceptual, a la vez que mejorar su nivel de relativismo cognitivo. En cuanto a la evaluaci??n del grado de relativismo de los participantes, los resultados indican que los estudiantes, en general, son capaces de reconocer la contradicci??n e identificar las versiones, pero tienen m??s dificultades para reconciliar posiciones. Parece haber una mejora del nivel del relativismo en los alumnos de cuarto de ESO respecto a los de primero. Los estudiantes con menos nivel de relativismo logran un porcentaje medio de cambio entre sus respuestas iniciales y finales superior a la media, lo que parece indicar que son estos estudiantes los que parecen obtener mayor beneficio de esta estrategia did??ctica consistente en presentar versiones alternativas. El patr??n motivacional de los alumnos participantes y el nivel de inter??s en la tarea, al menos con los instrumentos que hemos utilizado, no parecen influir en el grado de cambio logrado por los sujetos. Es necesario realizar nuevas investigaciones que contribuyan a precisar el papel de las variables motivacionales en el proceso de cambio conceptual.

La enseñanza de la Filosofía en la enseñanza media.

Realizar una comparativa de la evolución histórica de la enseñanza de la asignatura de Filosofía en la Bachillerato en España durante los siglos XIX y XX y también observar una amplia muestra de los sistemas educativos del mundo en los mismos siglos. La muestra de la investigación se compone de los planes de estudio de la asignatura de Filosofía en Bachillerato en España y las principales naciones de Europa y América en los siglos XX y XIX. Se han utilizado tres métodos de estudio: 1) el método histórico, que incluye la definición y delimitación del problema y una síntesis histórica; 2) la metodología comparada que incluye la teoría de las corrientes educativas; 3) las técnicas de triangulación, que consisten en la tipología de Denzin que considera el tiempo, el espacio, los niveles combinados, la triangulación de teorías, de la investigación y la metodología. Las hipótesis principales de estudio son: 1) constatar la existencia de la asignatura de Filosofía, en el marco de la Segunda Enseñanza, en España a lo largo de los siglos XIX y XX. 2) Constatar la existencia de la asignatura de Filosofía, en el marco de la Segunda Enseñanza de ámbito mundial hasta el año 2000. Se realiza un análisis histórico de la Filosofía en el Bachillerato en España desde 1845 al 1990, que incluye: la década moderada 1843-1854; la Reforma de la enseñaza, el Plan 'PIDAL' de 1845; la etapa del 1845 a 1864 con el predominio de las Corrientes Filosóficas; el proyecto educativo del Sexenio Revolucionario; la Filosofía en la Restauración, en la República y la Guerra civil, en la época de Franco; la Reforma educativa de 1990 con la Ley Orgánica General del Sistema Educativo por Comunidades Autónomas. Para realizar el estudio se ha utilizado la triangulación de las siguientes fuentes: planes de estudio, los libros de texto de Filosofía y la bibliografía sobre esta temática. La segunda parte de la investigación se centra en la enseñanza de la filosofía en la segunda enseñanza de 49 países del mundo. Se estudian los planes de estudio de la asignatura de filosofía de finales de los siglos XIX y XX de los países principales de Europa, países Árabes, los países Americanos, países de Asia y África. Se han utilizado los datos del cuestionario de la encuesta internacional de la UNESCO sobre 'Filosofía y Democracia en el mundo' de 1995. Se ha utilizado la técnica de triangulación aplicada a una amplia muestra a escala mundial que demuestra que la Filosofía es una asignatura de Educación Secundaria integrada en la gran mayoría de los sistemas educativos del mundo. Se concluye que en España la asignatura de Filosofía en los planes de estudio del Bachillerato ha sido una constante a lo largo de los siglos XIX y XX. Por otra parte, a finales del siglo XX la Filosofía es una asignatura en la Enseñanza Secundaria en un elevado número de países. Se llega a la conclusión que la asignatura de Filosofía, en los sistemas educativos, es un valor en alza a nivel mundial. Resumen basado en el de la publicación. p. 1106-1145 .

Los comics : el niño y el educador.

Tratar cuestiones referentes a la lectura y literatura infantil con especial atención al tema de los comics. Realizar a través de una encuesta un pequeño comentario y análisis de los resultados. Se trata sobre la lectura de comics durante la infancia. El primer capítulo trata sobre el análisis evolutivo del niño en la segunda y en la tercera infancia, de cómo es su desarrollo intelectual y cognitivo, el desarrollo afectivo, social, moral y los intereses y actividades. En el segundo capítulo se explica la función de educador, cómo sería su tarea educativa, el proceso de valoración en educación y las pautas que hacen posible la vivencia de los valores. Por último, en el tercer capitulo se explica el comic, cómo es su lectura, la historia, la temática, los personajes y aparece el material utilizado para el estudio, la encuesta, la muestra y los resultados. 1) En la segunda infancia hay una preferencia de la lectura de cuentos frente a la lectura de comics. 2) En la tercera infancia, niñez media, hay una preferencia de la lectura de comics frente a la lectura de libros. 3) Existe una tendencia a leer los comics en casa, siendo los más leídos los de frecuente venta en los kioscos: Thor, Superman, Spiderman, Mortadelo y Filemón, Zipi y Zape... 4) Se leen comics en los colegios, siendo los mas leídos los considerados de 'aventuras': Tintín. Asterix, Lucky-Luke... 5) Los valores que predominan en la segunda infancia son los vitales (belleza) y los éticos (bondad y maldad). 6) En la niñez media predominan los valores vitales (fuerza física) frente a los espirituales. 7) La amistad no queda reflejada en las encuestas.

Conditioning the chinchilla to novel sounds

This paper is a review of a study on chinchillas to test discrimination of sounds and related factors such as novelty, habituation and same-different discrimination.

Mediatización de la política: el discurso audiovisual del gobierno ecuatoriano y sus signos

Este trabajo de investigación y análisis aborda el discurso político audiovisual del gobierno ecuatoriano y su mediatización; en este marco, el objetivo principal apunta a detectar y definir los signos o elementos claves a nivel discursivo y comunicacional de ese discurso político audiovisual, para lo cual el corpus de análisis son 13 spots de propaganda de gobierno, emitidos entre enero y julio de 2008. Como un objetivo complementario se busca ubicar, al discurso materia de análisis, en un contexto socio-histórico que permita determinar sus antecedentes y comprender su génesis y desarrollo. En la estructuración, la tesis tiene 4 momentos definidos claramente: un marco teórico, en el cual se definen los conceptos y categorías que acompañaran el desarrollo del trabajo de análisis (política, discurso, mediatización, signos, entre los más importantes); un marco metodológico, en el que se detallan las líneas metodológicas y herramientas de investigación usadas para la aproximación al corpus de estudio; un marco referencial, en el que se presenta el contexto socio-histórico que enmarca el discurso; y, finalmente, se integra un capítulo en el cual se desarrolla el análisis de discurso de los spots de propaganda política del gobierno ecuatoriano y se generan las conclusiones de dicho trabajo

A customizable multi-agent system for distributed data mining

We present a general Multi-Agent System framework for distributed data mining based on a Peer-to-Peer model. Agent protocols are implemented through message-based asynchronous communication. The framework adopts a dynamic load balancing policy that is particularly suitable for irregular search algorithms. A modular design allows a separation of the general-purpose system protocols and software components from the specific data mining algorithm. The experimental evaluation has been carried out on a parallel frequent subgraph mining algorithm, which has shown good scalability performances.

Simulating current global river runoff with a global hydrological model: model revisions, validation, and sensitivity analysis

Global hydrological models (GHMs) model the land surface hydrologic dynamics of continental-scale river basins. Here we describe one such GHM, the Macro-scale - Probability-Distributed Moisture model.09 (Mac-PDM.09). The model has undergone a number of revisions since it was last applied in the hydrological literature. This paper serves to provide a detailed description of the latest version of the model. The main revisions include the following: (1) the ability for the model to be run for n repetitions, which provides more robust estimates of extreme hydrological behaviour, (2) the ability of the model to use a gridded field of coefficient of variation (CV) of daily rainfall for the stochastic disaggregation of monthly precipitation to daily precipitation, and (3) the model can now be forced with daily input climate data as well as monthly input climate data. We demonstrate the effects that each of these three revisions has on simulated runoff relative to before the revisions were applied. Importantly, we show that when Mac-PDM.09 is forced with monthly input data, it results in a negative runoff bias relative to when daily forcings are applied, for regions of the globe where the day-to-day variability in relative humidity is high. The runoff bias can be up to - 80% for a small selection of catchments but the absolute magnitude of the bias may be small. As such, we recommend future applications of Mac-PDM.09 that use monthly climate forcings acknowledge the bias as a limitation of the model. The performance of Mac-PDM.09 is evaluated by validating simulated runoff against observed runoff for 50 catchments. We also present a sensitivity analysis that demonstrates that simulated runoff is considerably more sensitive to method of PE calculation than to perturbations in soil moisture and field capacity parameters.

Discriminative pattern mining in software fault detection

We present a method to enhance fault localization for software systems based on a frequent pattern mining algorithm. Our method is based on a large set of test cases for a given set of programs in which faults can be detected. The test executions are recorded as function call trees. Based on test oracles the tests can be classified into successful and failing tests. A frequent pattern mining algorithm is used to identify frequent subtrees in successful and failing test executions. This information is used to rank functions according to their likelihood of containing a fault. The ranking suggests an order in which to examine the functions during fault analysis. We validate our approach experimentally using a subset of Siemens benchmark programs.

Design for design: support for creative practice in computer-supported collaborative work (CSCW) in design

This paper describes a novel methodology for observing and analysing collaborative design by using the concepts of cognitive dimensions related to concept-based misfit analysis. The study aims at gaining an insight into support for creative practice of graphical communication in collaborative design processes of designers while sketching within a shared white board and audio conferencing environment. Empirical data on design processes have been obtained from observation of groups of student designers solving an interior space-planning problem of a lounge-diner in a shared virtual environment. The results of the study provide recommendations for the design and development of interactive systems to support such collaborative design activities.

GIS in the cloud: implementing a web map service on Google App Engine

Many producers of geographic information are now disseminating their data using open web service protocols, notably those published by the Open Geospatial Consortium. There are many challenges inherent in running robust and reliable services at reasonable cost. Cloud computing provides a new kind of scalable infrastructure that could address many of these challenges. In this study we implement a Web Map Service for raster imagery within the Google App Engine environment. We discuss the challenges of developing GIS applications within this framework and the performance characteristics of the implementation. Results show that the application scales well to multiple simultaneous users and performance will be adequate for many applications, although concerns remain over issues such as latency spikes. We discuss the feasibility of implementing services within the free usage quotas of Google App Engine and the possibility of extending the approaches in this paper to other GIS applications.

Prebiotic effects: metabolic and health benefits

The different compartments of the gastrointestinal tract are inhabited by populations of micro-organisms. By far the most important predominant populations are in the colon where a true symbiosis with the host exists that is a key for well-being and health. For such a microbiota, 'normobiosis' characterises a composition of the gut 'ecosystem' in which micro-organisms with potential health benefits predominate in number over potentially harmful ones, in contrast to 'dysbiosis', in which one or a few potentially harmful micro-organisms are dominant, thus creating a disease-prone situation. The present document has been written by a group of both academic and industry experts (in the ILSI Europe Prebiotic Expert Group and Prebiotic Task Force, respectively). It does not aim to propose a new definition of a prebiotic nor to identify which food products are classified as prebiotic but rather to validate and expand the original idea of the prebiotic concept (that can be translated in 'prebiotic effects'), defined as: 'The selective stimulation of growth and/or activity(ies) of one or a limited number of microbial genus(era)/species in the gut microbiota that confer(s) health benefits to the host.' Thanks to the methodological and fundamental research of microbiologists, immense progress has very recently been made in our understanding of the gut microbiota. A large number of human intervention studies have been performed that have demonstrated that dietary consumption of certain food products can result in statistically significant changes in the composition of the gut microbiota in line with the prebiotic concept. Thus the prebiotic effect is now a well-established scientific fact. The more data are accumulating, the more it will be recognised that such changes in the microbiota's composition, especially increase in bifidobacteria, can be regarded as a marker of intestinal health. The review is divided in chapters that cover the major areas of nutrition research where a prebiotic effect has tentatively been investigated for potential health benefits. The prebiotic effect has been shown to associate with modulation of biomarkers and activity(ies) of the immune system. Confirming the studies in adults, it has been demonstrated that, in infant nutrition, the prebiotic effect includes a significant change of gut microbiota composition, especially an increase of faecal concentrations of bifidobacteria. This concomitantly improves stool quality (pH, SCFA, frequency and consistency), reduces the risk of gastroenteritis and infections, improves general well-being and reduces the incidence of allergic symptoms such as atopic eczema. Changes in the gut microbiota composition are classically considered as one of the many factors involved in the pathogenesis of either inflammatory bowel disease or irritable bowel syndrome. The use of particular food products with a prebiotic effect has thus been tested in clinical trials with the objective to improve the clinical activity and well-being of patients with such disorders. Promising beneficial effects have been demonstrated in some preliminary studies, including changes in gut microbiota composition (especially increase in bifidobacteria concentration). Often associated with toxic load and/or miscellaneous risk factors, colon cancer is another pathology for which a possible role of gut microbiota composition has been hypothesised. Numerous experimental studies have reported reduction in incidence of tumours and cancers after feeding specific food products with a prebiotic effect. Some of these studies (including one human trial) have also reported that, in such conditions, gut microbiota composition was modified (especially due to increased concentration of bifidobacteria). Dietary intake of particular food products with a prebiotic effect has been shown, especially in adolescents, but also tentatively in postmenopausal women, to increase Ca absorption as well as bone Ca accretion and bone mineral density. Recent data, both from experimental models and from human studies, support the beneficial effects of particular food products with prebiotic properties on energy homaeostasis, satiety regulation and body weight gain. Together, with data in obese animals and patients, these studies support the hypothesis that gut microbiota composition (especially the number of bifidobacteria) may contribute to modulate metabolic processes associated with syndrome X, especially obesity and diabetes type 2. It is plausible, even though not exclusive, that these effects are linked to the microbiota-induced changes and it is feasible to conclude that their mechanisms fit into the prebiotic effect. However, the role of such changes in these health benefits remains to be definitively proven. As a result of the research activity that followed the publication of the prebiotic concept 15 years ago, it has become clear that products that cause a selective modification in the gut microbiota's composition and/or activity(ies) and thus strengthens normobiosis could either induce beneficial physiological effects in the colon and also in extra-intestinal compartments or contribute towards reducing the risk of dysbiosis and associated intestinal and systemic pathologies.

Incorporation of cis-9, trans-11 conjugated linoleic acid and vaccenic acid (trans-11 18 : 1) into plasma and leucocyte lipids in healthy men consuming dairy products naturally enriched in these fatty acids

The present study investigated whether consuming dairy products naturally enriched in cis-9, trans-11 (c9,t11) conjugated linoleic acid (CLA) by modification of cattle feed increases the concentration of this isomer in plasma and cellular lipids in healthy men. The study had a double-blind cross-over design. Subjects aged 34-60 years consumed dairy products available from food retailers for 1 week and then either control (0.17 g c9,t11 CLA/d; 0.31 g trans-vaccenic acid (tVA)/d) or CLA-enriched (1.43 g c9,t11 CLA/d; 4.71 g tVA/d) dairy products for 6 weeks. After 7 weeks washout, this was repeated with the alternate products. c9,t11 CLA concentration in plasma lipids was lower after consuming the control products, which may reflect the two-fold greater c9,t11 CLA content of the commercial products. Consuming the CLA-enriched dairy products increased the c9,t11 CLA concentration in plasma phosphatidylcholine (PC) (38 %; P=0.035), triacylglycerol (TAG) (22 %; P < 0.0001) and cholesteryl esters (205 %; P < 0.0001), and in peripheral blood mononuclear cells (PBMC) (238 %; P < 0.0001), while tVA concentration was greater in plasma PC (65 %; P=0.035), TAG (98 %; P=0.001) and PBMC (84 %; P=0.004). Overall, the present study shows that consumption of naturally enriched dairy products in amounts similar to habitual intakes of these foods increased the c9,t11 CLA content of plasma and cellular lipids.

Effect of type and timing of oil supplements to sows during pregnancy on the growth performance and endocrine profile of low and normal birth weight offspring

Eighty-eight multiparous sows were used to evaluate whether type and timing of oil supplementation during gestation influences the incidence of low birth weight (LBW). Sows were allocated (eight per treatment) commercial sow pellets (3 kg/d; control diet) or an experimental diet consisting of control diet plus 10 % extra energy in the form of excess pellets, palm oil, olive oil (OO), sunflower oil (SO) or fish oil; experimental diets were fed during either the first half (G1) or second half (G2) of gestation. Growth performance and endocrine profile of LBW ( < 1·09 kg) and normal birth weight (NBW; 1·46–1·64 kg) offspring were compared. Maternal dietary supplementation altered the distribution curve for piglet birth weight. SOG1 sows had a greater proportion of LBW piglets (P < 0·05), whilst it was reduced in the OOG1 group (P < 0·05). Growth rate of LBW piglets was lower compared with their NBW siblings (P < 0·05) when dietary supplementation was offered in G2 but were similar for G1. At birth, LBW offspring of supplemented animals possessed more fat compared with the control group (P < 0·05); LBW offspring of control animals exhibited a more rapid decline in fat free mass/kg prior to weaning. Plasma metabolites and insulin concentrations were influenced by maternal diet and birth weight. In conclusion, maternal dietary supplementation altered the distribution of piglet birth weights and improved the energy status of LBW piglets. Supplementation with MUFA during G1 reduced the incidence of LBW, whereas PUFA had the reverse effect.