1,566 research outputs found

    Caracteres morfológicos y constitución química de variedades de almendra de Mallorca

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    Y-stent-assisted coil embolization of anterior circulation aneurysms using two solitaire AB devices: a single enter experience

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    Wide-neck intracranial aneurysms remain a challenge to endovascular treatment. We describe our experience in repairing wide-neck aneurysms of the anterior circulation located at arterial branch points using coil embolization assisted by Y-stenting using two Solitaire® stents. Six wide-neck intracranial aneurysms located on the middle cerebral artery bifurcation 3, pericallosal artery 1, and anterior communicating artery 2 were repaired by Y-stent-assisted coil embolization using two Solitaire® stents. Four cases were incidental findings of aneurysm and two cases were previously treated ruptured aneurysms that had undergone recanalization. All the cases were successfully treated without complications. Follow-up by digital subtraction angiography and magnetic resonance angiography at six months showed the stents to be patent with no recanalization of the aneurysm sacs. Repairing wide-neck aneurysms of the anterior circulation by Y-stent-assisted coil embolization using two Solitaire® stents is a simple and safe method of treating complex aneurysms. While the results are promising, larger series with longer term follow-ups are needed to corroborate that this treatment method is superior to other technique

    Prevalencia de la conducta prosocial según sexo y edad en una muestra de estudiantes colombianos

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    El presente estudio pretende analizar la conducta prosocial teniendo en cuenta las diferencias estadísticas según género y edad en población adolescente de estudiantes de tres colegios de la zona metropolitana de Bucaramanga, Colombia. La conducta prosocial fue codificada con el Teenage Inventory of Social Skills, que evalúa la conducta prosocial y agresiva de los adolescentes en las relaciones con sus iguales. El 50,4% de estudiantes de la investigación fueron identificados como prosociales. El análisis de proporciones reveló una prevalencia significativamente superior en conducta prosocial en las chicas que en los chicos. Con el paso de los años se produce un cambio de tendencia en la frecuencia de los estilos interpersonales, aunque la prosociabilidad es más frecuente a los 17 años.This study aims to analyze the prosocial behavior taking into account the statistical differences by gender and age in adolescent population of students from three schools in the metropolitan area of Bucaramanga, Colombia. Prosocial behavior was coded with the Teenage Inventory of Social Skills, which assesses prosocial and aggressive behavior in adolescent peer relationships. 50.4% of students in the research were identified as prosocial. The ratio analysis revealed a significantly higher prevalence in prosocial behavior in girls than in boys. Over the years, a shift in the frequency of interpersonal styles occurs, although prosociabili- dad is more common at age 17.peerReviewe

    Fuel loading and flammability in the Mediterranean Basin woody species with different post-fire regenerative strategies

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    12 páginas, 5 figuras, 3 tablas.The flammability and combustibility of plant communities are determined by species features related to growth-form, structure and physiology. In some ecosystems, such as the Mediterranean ones, these characteristics may contribute to the existence of fire-prone species. We measured several parameters associated with the flammability and fuel loading of dominant woody species with different post-fire regenerative strategies ( seeders and non-seeders) in shrublands in the western Mediterranean Basin. Overall, seeder species show lower fuel load but are more prone to burning owing to a higher dead-to-live fuel ratio, live fine-fuel proportion and dead fine-fuel proportion. Moreover, they burst into flame at lower temperatures than non-seeders. In the Mediterranean Basin, most seeder species emerged mainly during the Quaternary, under a highly fluctuating Mediterranean climate and during recurrent fires. We propose that properties related to the combustibility and flammability of seeders may be the result of selective pressures associated with both fire and climate. These results suggest that ecosystems dominated by seeder species are more susceptible to fire risk than those dominated by non-seeder species in the Mediterranean Basin. Therefore, the proportion of these types of species resulting from previous fire or management history is likely to determine the characteristics of future fire events.We thank M. Jané, E. Martí, A. Vilà-Cabrera, J. Garcia, B. Moreira, S. Ribeiro and C. Beseler for helping in the field and in the laboratory work. Also, special thanks are due to J. Piñol for his advice and suggestions, and to J. Peñuelas and G. Alessio for supporting the flammability tests. This study was funded by the Department of Universities, Research and Information Society of the Generalitat de Catalunya, the European social funds, and the Spanish Ministerio de Ciencia y Tecnología (MCYT) projects REN 2003–07198 and CGL2006–01293/BOS. It also contributes to the European research group (GDRE) ‘Mediterranean and mountain ecosystems in a changing world’ funded by the Generalitat de Catalunya and CNRS (Centre National de la Recherche Scientifique). CEAM (Fundación Centro de Estudios Ambientales del Mediterráneo) is supported by the Generalitat Valenciana and Bancaixa.Peer reviewe

    La vajilla campaniforme en las comarcas de L’Alcoià y El Comtat: aproximación a través del Estilo cerámico

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    En este artículo se presenta la vajilla campaniforme de las comarcas de L’Alcoià y El Comtat a través de un trabajo de recopilación bibliográfica y presentación de nuevos materiales procedentes de excavaciones, rebuscas y prospecciones, todos ellos depositados en el Museu Arqueològic Municipal Camil Visedo Moltó de Alcoy, el Centre d’Estudis Contestans y el Museu Arqueològic d’Ontinyent i la Vall d’Albaida. El estudio se ha elaborado desde de la perspectiva del Estilo cerámico con el objetivo de sistematizar el trabajo de análisis y comparación de las formas, técnicas y decoraciones

    Gene expression parallels synaptic excitability and plasticity changes in Alzheimer's disease

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    Altres ajuts: CIBERNED CB06/05/0042 i BrightFocus Foundation (A2014417S)Alzheimer's disease (AD) is a neurodegenerative disorder characterized by abnormal accumulation of β-amyloid and tau and synapse dysfunction in memory-related neural circuits. Pathological and functional changes in the medial temporal lobe, a region essential for explicit memory encoding, contribute to cognitive decline in AD. Surprisingly, functional imaging studies show increased activity of the hippocampus and associated cortical regions during memory tasks in presymptomatic and early AD stages, whereas brain activity declines as the disease progresses. These findings suggest an emerging scenario where early pathogenic events might increase neuronal excitability leading to enhanced brain activity before clinical manifestations of the disease, a stage that is followed by decreased brain activity as neurodegeneration progresses. The mechanisms linking pathology with synaptic excitability and plasticity changes leading to memory loss in AD remain largely unclear. Recent studies suggest that increased brain activity parallels enhanced expression of genes involved in synaptic transmission and plasticity in preclinical stages, whereas expression of synaptic and activity-dependent genes are reduced by the onset of pathological and cognitive symptoms. Here, we review recent evidences indicating a relationship between transcriptional deregulation of synaptic genes and neuronal activity and memory loss in AD and mouse models. These findings provide the basis for potential clinical applications of memory-related transcriptional programs and their regulatory mechanisms as novel biomarkers and therapeutic targets to restore brain function in AD and other cognitive disorders

    Analysis of the breakdown spot spatial distribution in Pt/HfO2/Pt capacitors using nearest neighbor statistics

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    The breakdown spot spatial distribution in Pt/HfO2/Pt capacitors is investigated using nearest neighbor statistics in combination with more conventional estimation methods such as the point-event and event-event distance distributions. The spots appear as a random point pattern over the top metal electrode and arise as a consequence of significant localized thermal effects caused by the application of high-voltage ramped stress to the devices. The reported study mainly involves the statistical characterization of the distances between each failure site and the nearest, second nearest,... kth nearest event and the comparison with the corresponding theoretical distributions for a complete spatial randomness (CSR) process. A method for detecting and correcting deviations from CSR based on a precise estimation of the average point intensity and the effective damaged device area is proposed. (C) 2013 AIP Publishing LLC

    Performance of NiCrAlY Coatings Deposited by Oxyfuel Thermal Spraying in High Temperature Chlorine Environment

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    A microcrystalline Ni-22Cr-10Al-1Y (wt.%) coating was deposited on AISI 304 stainless steel by the oxyfuel thermal spray technique. The deposited coating was subjected to heat treatment to improve the microstructure characteristics and its corresponding high-temperature properties. The isothermal high-temperature corrosion behavior at 650 and 700 °C in synthetic air and in the presence of 1% Cl2 was investigated using thermogravimetric analysis, x-ray diffraction, and scanning electron microscopy with energy-dispersive x-ray spectroscopy. The results indicated that the deposited NiCrAlY coating possessed acceptable oxidation-corrosion resistance at 650 °C owing to the formation of extensive amounts of the protective oxide of Cr2O3; NiO and a lesser amount of a Cr1.12 Ni2,88 metallic phase are also formed. At 700 °C, the coating lost its protective characteristic because of the excessive consumption of thermodynamically stable phases by oxidation-chlorination process. In this case, the steel base and the coating were attacked by chlorine during the exposure time; the mass gain of the NiCrAlY coating was slightly higher and provided only a limited protection up to 11 h; thereafter, breakdown of the layer of oxides occurred and this is attributed to the formation of non-protective oxides mainly β-Fe2O3 and Fe21.33O32 and the depletion of chromium
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