Evaluación de la competencia científica del alumnado de 4º de ESO según los ítems del Pisa

En el estudio se muestran los resultados de la evaluación de la competencia científica en 10 grupos de 4º de ESO a lo largo de 3 años (2006-08). En la evaluación se han aplicado 4 cuestiones de las liberadas del proyecto PISA. El grupo en el que la misma profesora impartió los 4 cursos de secundaria profundizando en el desarrollo de la capacidad comunicativa y autorregulación metacognitiva del alumnado, obtuvo los mejores resultados el primer año. Después de este diagnóstico se estableció un plan de formación permanente del profesorado de ciencias implicado centrado en la reflexión didáctica, la planificación de actividades menos memorísticas y la revisión de las preguntas de los exámenes comunes realizados a lo largo de los cursos. Los resultados obtenidos por los estudiantes a lo largo de los 3 años mejoraron significativamente

Activation of Type 1 Cannabinoid Receptor (CB1R) promotes neurogenesis in murine subventricular zone cell cultures

The endocannabinoid system has been implicated in the modulation of adult neurogenesis. Here, we describe the effect of type 1 cannabinoid receptor (CB1R) activation on self-renewal, proliferation and neuronal differentiation in mouse neonatal subventricular zone (SVZ) stem/progenitor cell cultures. Expression of CB1R was detected in SVZ-derived immature cells (Nestin-positive), neurons and astrocytes. Stimulation of the CB1R by (R)-(+)-Methanandamide (R-m-AEA) increased self-renewal of SVZ cells, as assessed by counting the number of secondary neurospheres and the number of Sox2+/+ cell pairs, an effect blocked by Notch pathway inhibition. Moreover, R-m-AEA treatment for 48 h, increased proliferation as assessed by BrdU incorporation assay, an effect mediated by activation of MAPK-ERK and AKT pathways. Surprisingly, stimulation of CB1R by R-m-AEA also promoted neuronal differentiation (without affecting glial differentiation), at 7 days, as shown by counting the number of NeuN-positive neurons in the cultures. Moreover, by monitoring intracellular calcium concentrations ([Ca2+](i)) in single cells following KCl and histamine stimuli, a method that allows the functional evaluation of neuronal differentiation, we observed an increase in neuronal-like cells. This proneurogenic effect was blocked when SVZ cells were co-incubated with R-m-AEA and the CB1R antagonist AM 251, for 7 days, thus indicating that this effect involves CB1R activation. In accordance with an effect on neuronal differentiation and maturation, R-m-AEA also increased neurite growth, as evaluated by quantifying and measuring the number of MAP2-positive processes. Taken together, these results demonstrate that CB1R activation induces proliferation, self-renewal and neuronal differentiation from mouse neonatal SVZ cell cultures.Fundacao para a Ciencia e a Tecnologia - Portugal [POCTI/SAU-NEU/68465/2006, PTDC/SAU-NEU/104415/2008, PTDC/SAU-NEU/101783/2008, POCTI/SAU-NEU/110838/2009]; Fundacao Calouste Gulbenkian [96542]; Fundacao para a Ciencia e Tecnologiainfo:eu-repo/semantics/publishedVersio

Global assessment of marine plastic exposure risk for oceanic birds

Plastic pollution is distributed patchily around the world’s oceans. Likewise, marine organisms that are vulnerable to plastic ingestion or entanglement have uneven distributions. Understanding where wildlife encounters plastic is crucial for targeting research and mitigation. Oceanic seabirds, particularly petrels, frequently ingest plastic, are highly threatened, and cover vast distances during foraging and migration. However, the spatial overlap between petrels and plastics is poorly understood. Here we combine marine plastic density estimates with individual movement data for 7137 birds of 77 petrel species to estimate relative exposure risk. We identify high exposure risk areas in the Mediterranean and Black seas, and the northeast Pacific, northwest Pacific, South Atlantic and southwest Indian oceans. Plastic exposure risk varies greatly among species and populations, and between breeding and non-breeding seasons. Exposure risk is disproportionately high for Threatened species. Outside the Mediterranean and Black seas, exposure risk is highest in the high seas and Exclusive Economic Zones (EEZs) of the USA, Japan, and the UK. Birds generally had higher plastic exposure risk outside the EEZ of the country where they breed. We identify conservation and research priorities, and highlight that international collaboration is key to addressing the impacts of marine plastic on wide-ranging species

Global assessment of marine plastic exposure risk for oceanic birds

Plastic pollution is distributed patchily around the world's oceans. Likewise, marine organisms that are vulnerable to plastic ingestion or entanglement have uneven distributions. Understanding where wildlife encounters plastic is crucial for targeting research and mitigation. Oceanic seabirds, particularly petrels, frequently ingest plastic, are highly threatened, and cover vast distances during foraging and migration. However, the spatial overlap between petrels and plastics is poorly understood. Here we combine marine plastic density estimates with individual movement data for 7137 birds of 77 petrel species to estimate relative exposure risk. We identify high exposure risk areas in the Mediterranean and Black seas, and the northeast Pacific, northwest Pacific, South Atlantic and southwest Indian oceans. Plastic exposure risk varies greatly among species and populations, and between breeding and non-breeding seasons. Exposure risk is disproportionately high for Threatened species. Outside the Mediterranean and Black seas, exposure risk is highest in the high seas and Exclusive Economic Zones (EEZs) of the USA, Japan, and the UK. Birds generally had higher plastic exposure risk outside the EEZ of the country where they breed. We identify conservation and research priorities, and highlight that international collaboration is key to addressing the impacts of marine plastic on wide-ranging species.B.L.C., C.H., and A.M. were funded by the Cambridge Conservation Initiative’s Collaborative Fund sponsored by the Prince Albert II of Monaco Foundation. E.J.P. was supported by the Natural Environment Research Council C-CLEAR doctoral training programme (Grant no. NE/S007164/1). We are grateful to all those who assisted with the collection and curation of tracking data. Further details are provided in the Supplementary Acknowledgements. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.Peer reviewe

Global assessment of marine plastic exposure risk for oceanic birds

Plastic pollution is distributed patchily around the world’s oceans. Likewise, marine organisms that are vulnerable to plastic ingestion or entanglement have uneven distributions. Understanding where wildlife encounters plastic is crucial for targeting research and mitigation. Oceanic seabirds, particularly petrels, frequently ingest plastic, are highly threatened, and cover vast distances during foraging and migration. However, the spatial overlap between petrels and plastics is poorly understood. Here we combine marine plastic density estimates with individual movement data for 7137 birds of 77 petrel species to estimate relative exposure risk. We identify high exposure risk areas in the Mediterranean and Black seas, and the northeast Pacific, northwest Pacific, South Atlantic and southwest Indian oceans. Plastic exposure risk varies greatly among species and populations, and between breeding and non-breeding seasons. Exposure risk is disproportionately high for Threatened species. Outside the Mediterranean and Black seas, exposure risk is highest in the high seas and Exclusive Economic Zones (EEZs) of the USA, Japan, and the UK. Birds generally had higher plastic exposure risk outside the EEZ of the country where they breed. We identify conservation and research priorities, and highlight that international collaboration is key to addressing the impacts of marine plastic on wide-ranging species

Investigación en la escuela

Aborda la importancia de las preguntas formuladas por los alumnos en el aula dentro de la construcción del conocimiento científico. Se plantea promover la evolución de los modelos explicativos iniciales del alumnado hacia otros modelos que incorporen la complejidad, a partir de lo que se han denominado preguntas mediadoras que se caracterizan por ser dinámicas, focalizadoras y escalares. Estas preguntas deben ser respondidas a través de un proceso no-lineal que conlleva la formulación de una red de sub-preguntas. Por último, se ponen dos ejemplos de los resultados alcanzados con alumnos en los que se ha aplicado la técnica de la pregunta mediadora.AndalucíaES

Primary antibodies used for immunocytochemistry.

<p>Primary antibodies used for immunocytochemistry.</p

(R)-(+)-Methanandamide induces the differentiation of GABAergic neurons and neuritogenesis.

<p><b>A:</b> Schematic representation of the protocol. <b>B:</b> Bar graph depicts the numbers of either VGAT- or TH/βIII tubulin-positive cells, expressed as percentage of total cells. The data are expressed as percentage ± SEM. N = 3. *<i>P</i><0.05 using unpaired Student’s t test for comparison with control. <b>C:</b> Schematic representation of the protocol used for studying neuritogenesis. <b>D:</b> Representative confocal digital images of the GFP (green), MAP2 (red), Hoechst staining (blue), in control cultures and in cultures exposed to R-m-AEA. Scale bar = 20 µm. <b>E:</b> Bar graphs depict (from left to right): total length (µm), number of primary and number of secondary ramifications of MAP2 neurites per cell. N = 3. **P<0.01 using unpaired student’s t test for comparison with control. MAP2: Microtubule-associated protein 2; TH: tyrosine hydroxylase; βIII tubulin: Neuron-specific class III beta-tubulin; VGAT: vesicular GABA transporter.</p

SVZ cells express CB1R.

<p><b>A:</b> Detection of CB1R by Western blotting in SVZ. Lane 1 corresponds to SVZ proliferating cells, lane 2 to SVZ extract from adult C57Bl6 mice and lane 3 to the negative control (total proteins from CB1R-KO mice). <b>B–F:</b> Representative confocal digital images depicting CB1R immunoreactivity in SVZ cells after 7 days of differentiation [CB1R (in red); nestin (in green), GFAP (in green), PSA-NCAM (in green), DCX (in green), βIII tubulin (in green), MAP2 (in green) and Hoechst 33342 (used to visualize cell nuclei, in blue)]. c1, e1 and f1 are magnifications of squares in C, E and F, respectively. Scale bars = 20 µm. SVZ: subventricular zone; GFAP: Glial fibrillary acidic protein; PSA-NCAM: Polysialylated neural cell adhesion; βIII tubulin: Neuron-specific class III beta-tubulin; MAP2: Microtubule-associated protein 2; CB1R: CB1 receptor.</p

(R)-(+)-Methanandamide does not induce glial differentiation in SVZ cultures through CB1R activation.

<p><b>A:</b> Protocol used for studying glial differentiation. <b>B:</b> Western blot analysis of GFAP and Olig2 protein levels in SVZ. Data are expressed as mean ± SEM. N = 4. <b>C:</b> Bar graph depicts the number of GFAP and Olig2-positive cells, expressed as the percentage of total cells <i>per</i> culture. Data are expressed as mean ± SEM. N = 3. <b>D:</b> Representative fluorescent digital images of GFAP-positive cells (green), Olig2-positive cells (red) and Hoechst staining (blue nuclei). Scale bar = 50 µm.</p