Describe and draw in science. The importance of drawing in students' mental representations

El presente trabajo pretende valorar los resultados obtenidos mediante la utilización del dibujo y de las descripciones a lo largo de una actividad basada en la observación de la morfología de las hormigas. Se plantea un trabajo individual y autónomo donde los participantes, en 3 etapas diferentes, deben tratar de dibujar o describir su observación de muestras vivas de hormigas. Los resultados de la investigación son muy significativos, puesto que encontramos diferencias estadísticas entre la utilización de las dos estrategias, así como entre las producciones de cada etapa, pudiendo ver cómo evolucionan sus representaciones mentales. Evidenciamos, de esta manera, que la estrategia de dibujar mejora los resultados en procesos observacionales respecto a la tarea de describir, especialmente en la adquisición de información y en su comunicación.The following investigation pretends to compare the results obtained by using drawing and writing descriptions along an activity based on ants' morphology observation. The activity is based on students' autonomous work, where students have to draw/describe in 3 different times after the visualization of live ants samples. The results of the investigation are strongly significatives, we found statistical differences between both strategies productions along the activity, allowing us to study the evolution of the mental representations. After the investigation, we can show that the drawing strategy improves the results involving observational processes, specially by improving information acquisition and communication

Describir y dibujar en ciencias. La importancia del dibujo en las representaciones mentales del alumnado

El presente trabajo pretende valorar los resultados obtenidos mediante la utilización del dibujo y de las descripciones a lo largo de una actividad basada en la observación de la morfología de las hormigas. Se plantea un trabajo individual y autónomo donde los participantes, en 3 etapas diferentes, deben tratar de dibujar o describir su observación de muestras vivas de hormigas. Los resultados de la investigación son muy significativos, puesto que encontramos diferencias estadísticas entre la utilización de las dos estrategias, así como entre las producciones de cada etapa, pudiendo ver cómo evolucionan sus representaciones mentales. Evidenciamos, de esta manera, que la estrategia de dibujar mejora los resultados en procesos observacionales respecto a la tarea de describir, especialmente en la adquisición de información y en su comunicació

Cardioembolic Stroke Diagnosis Using Blood Biomarkers

Stroke is one of the main causes of death and disability in the world. Cardioembolic etiology accounts for approximately one fifth of all ischemic strokes whereas 25-30% remains undetermined even after an advanced diagnostic workup. Despite there is not any biomarker currently approved to distinguish cardioembolic stroke among other etiologies in clinical practice the use of biomarkers represents a promising valuable complement to determine stroke etiology reducing the number of cryptogenic strokes and aiding in the prescription of the most appropriated primary and secondary treatments in order to minimize therapeutic risks and to avoid recurrences. In this review we present an update about specific cardioembolic stroke-related biomarkers at a protein, transcriptomic and genetic level. Finally, we also focused on reported biomarkers associated with atrial fibrillation (a cardiac illness strongly related with cardioembolic stroke subtype) thus with a potential to become biomarkers to detect cardioembolic stroke in the future

Terahertz epsilon-near-zero graded-index lens

An epsilon-near-zero graded-index converging lens with planar faces is proposed and analyzed. Each perfectly-electric conducting (PEC) waveguide comprising the lens operates slightly above its cut-off frequency and has the same length but different cross-sectional dimensions. This allows controlling individually the propagation constant and the normalized characteristic impedance of each waveguide for the desired phase front at the lens output while Fresnel reflection losses are minimized. A complete theoretical analysis based on the waveguide theory and Fermat’s principle is provided. This is complemented with numerical simulation results of two-dimensional and three-dimensional lenses, made of PEC and aluminum, respectively, and working in the terahertz regime, which show good agreement with the analytical work.Effort sponsored by Spanish Government under contracts Consolider “Engineering Metamaterials” CSD2008-00066 and TEC2011-28664-C02-01. P.R.-U. is sponsored by the Government of Navarra under funding program “Formación de tecnólogos” 055/01/11. M.N.- C. is supported by the Imperial College Junior Research Fellowship. M. B. acknowledges funding by the Spanish Government under the research contract program Ramon y Cajal RYC-2011-08221. N.E. acknowledges the support from the US Office of Naval Research (ONR) Multidisciplinary University Research Initiatives (MURI) grant number N00014-10-1- 0942

Conserved bacterial-binding peptides of the scavenger-like lymphocyte receptor CD6 protect from mouse experimental sepsis

Sepsis is an unmet clinical need constituting one of the most important causes of death worldwide, a fact aggravated by the appearance of multidrug resistant strains due to indiscriminate use of antibiotics. Host innate immune receptors involved in pathogen-associated molecular patterns (PAMPs) recognition represent a source of broad-spectrum therapies alternative or adjunctive to antibiotics. Among the few members of the ancient and highly conserved scavenger receptor cysteine-rich superfamily (SRCR-SF) sharing bacterial-binding properties there is CD6, a lymphocyte-specific surface receptor. Here, we analyze the bacterial-binding properties of three conserved short peptides (11-mer) mapping at extracellular SRCR domains of human CD6 (CD6.PD1, GTVEVRLEASW; CD6.PD2 GRVEMLEHGEW; and CD6.PD3, GQVEVHFRGVW). All peptides show high binding affinity for PAMPs from Gram-negative (lipopolysaccharide; Kd from 3.5 to 3,000 nM) and Gram-positive (lipoteichoic acid; Kd from 36 to 680 nM) bacteria. The CD6.PD3 peptide possesses broad bacterial-agglutination properties and improved survival of mice undergoing polymicrobial sepsis in a dose- and time-dependent manner. Accordingly, CD6.PD3 triggers a decrease in serum levels of both pro-inflammatory cytokines and bacterial load. Interestingly, CD6.PD3 shows additive survival effects on septic mice when combined with Imipenem/Cilastatin. These results illustrate the therapeutic potential of peptides retaining the bacterial-binding properties of native CD6

Integrative Multi-omics Analysis to Characterize Human Brain Ischemia

Stroke is a major cause of death and disability. A better comprehension of stroke pathophysiology is fundamental to reduce its dramatic outcome. The use of high-throughput unbiased omics approaches and the integration of these data might deepen the knowledge of stroke at the molecular level, depicting the interaction between different molecular units. We aimed to identify protein and gene expression changes in the human brain after ischemia through an integrative approach to join the information of both omics analyses. The translational potential of our results was explored in a pilot study with blood samples from ischemic stroke patients. Proteomics and transcriptomics discovery studies were performed in human brain samples from six deceased stroke patients, comparing the infarct core with the corresponding contralateral brain region, unveiling 128 proteins and 2716 genes significantly dysregulated after stroke. Integrative bioinformatics analyses joining both datasets exposed canonical pathways altered in the ischemic area, highlighting the most influential molecules. Among the molecules with the highest fold-change, 28 genes and 9 proteins were selected to be validated in five independent human brain samples using orthogonal techniques. Our results were confirmed for NCDN, RAB3C, ST4A1, DNM1L, A1AG1, A1AT, JAM3, VTDB, ANXA1, ANXA2, and IL8. Finally, circulating levels of the validated proteins were explored in ischemic stroke patients. Fluctuations of A1AG1 and A1AT, both up-regulated in the ischemic brain, were detected in blood along the first week after onset. In summary, our results expand the knowledge of ischemic stroke pathology, revealing key molecules to be further explored as biomarkers and/or therapeutic targets

Integrative Multi-omics Analysis to Characterize Human Brain Ischemia

Stroke is a major cause of death and disability. A better comprehension of stroke pathophysiology is fundamental to reduce its dramatic outcome. The use of high-throughput unbiased omics approaches and the integration of these data might deepen the knowledge of stroke at the molecular level, depicting the interaction between different molecular units. We aimed to identify protein and gene expression changes in the human brain after ischemia through an integrative approach to join the information of both omics analyses. The translational potential of our results was explored in a pilot study with blood samples from ischemic stroke patients. Proteomics and transcriptomics discovery studies were performed in human brain samples from six deceased stroke patients, comparing the infarct core with the corresponding contralateral brain region, unveiling 128 proteins and 2716 genes significantly dysregulated after stroke. Integrative bioinformatics analyses joining both datasets exposed canonical pathways altered in the ischemic area, highlighting the most influential molecules. Among the molecules with the highest fold-change, 28 genes and 9 proteins were selected to be validated in five independent human brain samples using orthogonal techniques. Our results were confirmed for NCDN, RAB3C, ST4A1, DNM1L, A1AG1, A1AT, JAM3, VTDB, ANXA1, ANXA2, and IL8. Finally, circulating levels of the validated proteins were explored in ischemic stroke patients. Fluctuations of A1AG1 and A1AT, both up-regulated in the ischemic brain, were detected in blood along the first week after onset. In summary, our results expand the knowledge of ischemic stroke pathology, revealing key molecules to be further explored as biomarkers and/or therapeutic targets. Graphical abstract: [Figure not available: see fulltext.].This work has been funded by Instituto de Salud Carlos III (PI15/00354, PI18/00804), MINECO (MTM2015-64465-C2-1R) and GRBIO (2014-SGR-464) and co-financed by the European Regional Development Fund (FEDER). Neurovascular Research Laboratory takes part in the Spanish stroke research network INVICTUS + (RD16/0019/0021). L.R is supported by a pre-doctoral fellowship from the Instituto de Salud Carlos III (IFI17/00012).Peer reviewe

Recursos i estratègies per una visió de l'art des de les ciències experimentals : la ciència de l'art

Resumen basado en el del autor. Se acompaña de tres anexos, uno con la procedencia de las imágenes del trabajo, otro con un listado de artistas y el tercero con un listado de museos de todo el mundo, estos dos últimos con enlaces a páginas web de referencia. También incluye una extensa bibliografíaSe presenta la relación que tienen los avances técnicos y científicos en las diferentes épocas con la historia del arte. Por ejemplo se demuestra como la paleta de colores va ampliándose a medida que los pigmentos y colorantes van apareciendo. Las obras de arte, además del mensaje del artista, hablan de la época en la que fueron realizadas. Un estudio más profundo de la obra indicará cómo estaba la ciencia en aquel tiempo, qué tecnología aplicaban y como relacionaban todos los conocimientos del momento. Para desarrollar este trabajo se incluyen nueve prácticas que se pueden realizar con los materiales que ya existen en los centros docentes.Generalitat de Catalunya. Departament d'EnsenyamentCataluñaGeneralitat de Catalunya. Departament d'Ensenyament. Biblioteca; Via Augusta 202-226; 08021 Barcelona; Tel. +34934006900; Fax +34934006903ES

Aplicaciones proteómicas para el descubrimiento de biomarcadores diagnósticos en ictus

El ictus representa uno de los trastornos neurológicos más severos. En nuestro entorno, esta patología cerebrovascular revela una elevada prevalencia y se sitúa como segunda causa de muerte y primera causa de invalidez y discapacidad, lo que se traduce en un extraordinario impacto a nivel económico, sanitario y social. El diagnóstico del ictus se basa en la evaluación del paciente a través de técnicas de neuroimagen, identificando si la lesión cerebral es de naturaleza isquémica, hemorrágica o se trata de una patología mimetizante. El tratamiento específico del ictus isquémico agudo incluye la trombolisis o los tratamientos recanalizadores intraarteriales, ambos dirigidos a lograr la recanalización de la arteria ocluida. En cambio, en el ictus hemorrágico, las estrategias de reducción de la presión arterial presentan resultados prometedores pero actualmente se encuentran aún bajo evaluación. Para asegurar la administración del tratamiento agudo adecuado resulta esencial la diferenciación entre los distintos subtipos de ictus así como su distinción de otras patologías mimetizantes de forma rápida y precisa. El uso de biomarcadores para el diagnóstico del ictus representa una herramienta alternativa especialmente aplicable en entornos donde la accesibilidad a la neuroimagen resulta limitada, como el escenario pre-hospitalario, centros sanitarios de primer y segundo nivel, zonas con baja densidad de población o países en vías de desarrollo; y que permitiría agilizar la evaluación del paciente en la fase hiperaguda tras el evento vascular. Actualmente, ningún biomarcador está siendo aplicado en el manejo de los pacientes que han sufrido un ictus, pero algunos candidatos ya han evidenciado su potencial en estudios multicéntricos y diversos meta-análisis. Buenos ejemplos de ello son el péptido natriurétio de tipo B (BNP) para identificar la etiología cardioembólica del ictus isquémico, o la medición de copeptina en la predicción del pronóstico de los pacientes. El objetivo que persiguen los trabajos incluidos en esta tesis doctoral es identificar nuevos biomarcadores candidatos para el diagnóstico del ictus a través de técnicas proteómicas aplicadas en modelos in-vivo e in-vitro, así como en muestras humanas. Por un lado, mediante técnicas de cuantificación SILAC y label-free, junto con el empleo de MALDI imaging, hemos podido identificar proteínas involucradas en la isquemia cerebral para su evaluación como biomarcadores específicos de esta patología. Por otro lado, hemos logrado describir distintas proteínas capaces de discriminar los ictus isquémicos de aquellos de naturaleza hemorrágica mediante su cuantificación en plasma. Además, hemos sido capaces de evaluar el valor añadido de algunos de los candidatos identificados aportando información sobre su capacidad predictiva y de discriminación. Los resultados de esta tesis doctoral han permitido avanzar un paso más en el conocimiento de la fisiopatología de la isquemia cerebral y suponen la apertura de nuevas vías de investigación en futuros estudios. Además hemos podido examinar nuevos candidatos para la diferenciación de los subtipos isquémico y hemorrágico. Explorar el valor real de los candidatos descritos como biomarcadores diagnósticos en cohortes multicéntricas representa el siguiente paso derivado de los resultados presentados en esta tesis doctoral. La implementación del uso de biomarcadores diagnósticos de ictus en la práctica clínica diaria parece un excelente escenario de futuro que podría traducirse en una clara mejoría en el manejo de los pacientes en fase aguda y en una mejor administración de los recursos socio-sanitarios.Stroke is one of the most severe neurological disorders. In our society, this cerebrovascular disease reveals a high prevalence and represents the second cause of dead and the first cause of disability, with a dramatic impact at the economic, social and health systems. The evaluation of patients for stroke diagnostic is based on neuroimaging, classifying the lesions of ischemic and hemorrhagic nature or identifying mimicking pathologies. The specific treatment for acute ischemic stroke includes thrombolysis or intraarterial recanalization, aiming to achieve the opening of the occluded artery. In contrast, in hemorrhagic stroke, blood-pressure lowering strategies are currently under evaluation, although promising results have been reported. In order to ensure the most suitable acute treatment, it is absolutely essential an accurate differentiation of ischemic and hemorrhagic stroke and the identification of stroke mimicking conditions. The use of biomarkers for stroke diagnosis represents an alternative tool especially applicable in those contexts with limited neuroimaging availability, such as pre-hospital settings, primary health centers, low population density areas or developing countries. Currently, although no biomarker is still being clinically applied in the management of stoke patients, some candidates have evidenced a great potential in multi-centric studies and different meta-analyses. Some examples are B-type natriuretic peptide (BNP) for the identification of cardioembolic strokes, or copeptin for the prediction of patients’ prognosis. The main aim of the studies included in this doctoral dissertation is the identification of new putative biomarkers for stroke diagnosis using diverse proteomic approaches in in-vivo and in-vitro models, as well as in human samples. On the one hand, we describe different proteins involved in cerebral ischemia for their evaluation as specific biomarkers. On the other hand, we identified different bloodstream proteins with discerning ability between acute ischemic and hemorrhagic strokes. The added value of some of these markers has been statistically evaluated, raising new information about their predictive and discriminative capability. The results of this doctoral dissertation represent an additional step in the knowledge of cerebral ischemia pathophysiology and opens new paths for future research. Besides, we could examine new candidates for the differentiation of the ischemic and hemorrhagic stroke subtypes. The evaluation of the described biomarker candidates and their real diagnostic value will be assessed in future multi-centric analyses as a next step derived from the results reported. The daily clinical implementation of diagnostic biomarkers of stroke might be translated in a dramatic improvement in the management of acute stroke patients and in a better administration of the social and healthcare resources