Els models, organitzadors del currícul en biologia

Es presenta una proposta d'organització del currículum de biologia basada en determinats models teòrics. Hi justifiquem la seva idoneïtat i validesa i presentem alguns dels resultats de la seva aplicació a l'aula

Características de los ejercicios de prácticas de laboratorio incluidos en los libros de textos de Ciencias utilizados en Cataluña

The laboratory exercices in science textbooks used in grades 9 to 12 in Catalonian schools were content analyzed by three instruments: The Inquiry Leve1 Index (ILI), the Laboratory Assessment Inventory (LAI) and the Laboratory Dimenssions Inventory (LDI). The analysis was carried out by 24 teachers under the guidance of two science educators as an assignment in an in-service course on teaching and evaluation in the laboratory. It was found that the number of laboratory exercises offered in Catalonian science texbooks is rather small compared with texbooks in countries such as the U. K. and U.S.A. Most of the exercises are of low inquiry level featuring manipulation but missing high other inquiry skills such as formulating questions and hypotheses, designing experiments, etc. The relationship between practical work and theory is hardly indicated and the potential of the laboratory as a means to enhancing concept learning andlor developing social skills are hardly being considered. There is an urgent need to reform laboratory work in Catalonian schools

L'ús d'animacions-TIC a la classe de biologia

Les animacions que trobem a les webs són un nou recurs didàctic del que disposem els ensenyants per promoure l'aprenentatge dels nostres alumnes. Però la seva eficàcia passa per saber quins són els aspectes del seu disseny que poden afavorir l'aprenentatge i quines són les millors maneres d'utilitzar-les a l'aula. En aquest article es resumeix una recerca, disponible a la xarxa, en la que s'han analitzat aspectes com: a) Característiques del disseny de les "animacions" que millor poden afavorir l'aprenentatge, b) Ús que en fa el professorat, i c) Ús que en fa l'alumnat

L’ús d’animacions-TIC a la classe de biologia

Les animacions que trobem a les webs són un nou recurs didàctic del que disposem els ensenyants per promoure l’aprenentatge dels nostres alumnes. Però la seva eficàcia passa per saber quins són els aspectes del seu disseny que poden afavorir l’aprenentatge i quines són les millors maneres d’utilitzar-les a l’aula. En aquest article es resumeix una recerca, disponible a la xarxa, en la que s’han analitzat aspectes com: a) Característiques del disseny de les “animacions” que millor poden afavorir l’aprenentatge, b) Ús que en fa el professorat, i c) Ús que en fa l’alumnat

Un modelo didáctico para la Formación Inicial del Profesorado de Ciencias

En este artículo se discuten los componentes -epistemológico, psicológico y socio-pedagógico- de un modelo de formación inicial del profesorado de ciencias para la secundaria, que se ha venido desarrollando en el CAP de la Universitat Autónoma de Barcelona. A modo de ejemplo, se presenta una secuencia de aprendizaje que permite hacerse una idea de cómo se concreta este modelo en el aula de «Didáctica de las Ciencias Naturales».This article discusses the epistemological, psychological and socio - pedagogical components of a preservice secondary science teacher training model. The model is being developed at CAP of Universitat Autónoma de Barcelona. As an example, a learning sequence is presented for understanding how this model is applied at «Science Teaching» course

Estudios de cómic en la Universidad de Alicante. De Unicómic a una red de investigación

Con el fin de continuar con la labor de difusión de la historieta como arte, objeto de estudio académico y herramienta didáctica que desde 1999 realiza la asociación Unicómic, coordinadora de las Jornadas del Cómic de la Universidad de Alicante de idéntico nombre, y a partir de un curso sobre la relación del noveno arte con la Literatura y la Historia celebrado en noviembre de 2013, buena parte del profesorado de este último junto a otros investigadores con inquietudes similares acaban conformando una red de investigación centrada en las posibilidades del cómic como instrumento docente, de nombre Cómic como elemento didáctico. Posibilidades de la narración gráfica en disciplinas académicas y tramos de preparación a la universidad. Dicha red articula una serie de investigaciones que pasa por la realización y tutorización de Trabajos de Fin de Grado, la participación de sus miembros en cursos académicos de diversa índole y la labor continuista de coordinación de las propias jornadas de Unicómic

Multiphoton imaging of melanoma 3D models with plasmonic nanocapsules

We report the synthesis of plasmonic nanocapsules and the cellular responses they induce in 3D melanoma models for their perspective use as a photothermal therapeutic agent. The wall of the nanocapsules is composed of polyelectrolytes. The inner part is functionalized with discrete gold nanoislands. The cavity of the nanocapsules contains a fluorescent payload to show their ability for loading a cargo. The nanocapsules exhibit simultaneous two-photon luminescent, fluorescent properties and X-ray contrasting ability. The average fluorescence lifetime (τ) of the nanocapsules measured with FLIM (0.3 ns) is maintained regardless of the intracellular environment, thus proving their abilities for bioimaging of models such as 3D spheroids with a complex architecture. Their multimodal imaging properties are exploited for the first time to study tumorspheres cellular responses exposed to the nanocapsules. Specifically, we studied cellular uptake, toxicity, intracellular fate, generation of reactive oxygen species, and effect on the levels of hypoxia by using multi-photon and confocal laser scanning microscopy. Because of the high X-ray attenuation and atomic number of the gold nanostructure, we imaged the nanocapsule-cell interactions without processing the sample. We confirmed maintenance of the nanocapsules’ geometry in the intracellular milieu with no impairment of the cellular ultrastructure. Furthermore, we observed the lack of cellular toxicity and no alteration in oxygen or reactive oxygen species levels. These results in 3D melanoma models contribute to the development of these nanocapsules for their exploitation in future applications as agents for imaging-guided photothermal therapy. Statement of Significance: The novelty of the work is that our plasmonic nanocapsules are multimodal. They are responsive to X-ray and to multiphoton and single-photon excitation. This allowed us to study their interaction with 2D and 3D cellular structures and specifically to obtain information on tumor cell parameters such as hypoxia, reactive oxygen species, and toxicity. These nanocapsules will be further validated as imaging-guided photothermal probe

The effects of sildenafil citrate on the fetoplacental development and hemodynamics in a rabbit model of intrauterina growth restriction

The present study evaluated the effectiveness of sildenafil citrate (SC) to improve placental and fetal growth in a diet-induced rabbit model of intrauterine growth restriction (IUGR). Pregnant rabbits were fed either ad libitum (Group C) or restricted to 50% of dietary requirements (Group R) or restricted and treated with SC (Group SC). The treatment with SC improved placental development by increasing vascularity and vessel hypertrophy in the decidua. The assessment of feto–placental haemodynamics showed higher resistance and pulsatility indices at the middle cerebral artery (MCA) in fetuses treated with SC when compared with Group R, which had increased systolic peak and time-averaged mean velocities at the MCA. Furthermore, fetuses in the SC group had significantly higher biparietal and thoracic diameters and longer crown–rump lengths than fetuses in Group R. Hence, the SC group had a reduced IUGR rate and a higher kit size at birth compared with Group R. In conclusion, SC may provide potential benefits in pregnancies with placental insufficiency and IUGR, partially counteracting the negative effects of food restriction on placental development and fetal growth. However, the present study also found evidence of a possible blood overflow in the brain that warrants further investigation