22 research outputs found
O ensino das Ciências Sociais nas escolas primárias. Análise dos gestos profissionais, em classe, com o uso das Aulas Digitais Móveis
The general problem that guides the work is related to the use of Information Technology and Educational Communication (TICE) that teachers do in Social Sciences classes in primary schools. The methodology used was to make a cut of the reality, to focus on three different moments of a didactic situation. First of all, an interview with the teacher focused on the planning of the didactic sequence to be implemented, a second moment of observation and recording of the didactic activity through the videocopy technique, and for the last time a self-confrontation interview. The analysis aims to show, in a general way, how teachers in social science classes make use of the Digital Mobile Classrooms (ADM). La problemática general que orienta el presente trabajo está relacionada con el uso de las Tecnologías de la Información y Comunicación Educativas (TICE) que hacen los maestros en las clases de Ciencias Sociales en escuelas de nivel primario. La metodología utilizada consistió en realizar un recorte de la realidad, focalizando tres diferentes momentos de una situación didáctica. En primer lugar, una entrevista al maestro centrada en la planificación de la secuencia didáctica a implementar, un segundo momento de observación y registro de la actividad didáctica mediante la técnica de videoscopía, y por último una entrevista de autoconfrontación. En el análisis se pretende mostrar, de manera general como los maestros en las clases de ciencias sociales hacen uso de las Aulas Digitales Móviles (ADM). A problemática geral que orienta o presente trabalho está relacionada com o uso das Tecnologias da Informação e Comunicação Educativas (TICE) que realizam os professores nas classes de ciências sociais, nas escolas de nível primário. A metodologia utilizada focaliza em três momentos diferentes da situação didática. Em primeiro lugar, uma entrevista ao professor centrada na planificação da sequência didática a implementar; um segundo momento de observação e registro da atividade didática através da técnica de videoscopia y, por último, uma entrevista de autoconfrontação. Na análise, pretende-se demonstrar, de maneira geral como os professores nas classes de ciências sociais usam Aulas Digitais Móveis (ADM).
Seismic performance evaluation of traditional timber Hımış frames: capacity spectrum method based assessment
Timber constructions have been widely suggested to be seismically resistant based on post-disaster reconnaissance studies. This observation has, however, remained to a large extent anecdotal due to the lack of experimental work supporting it, especially for certain timber architectural forms, including traditional timber frame “hımış” structures. To fill this gap, the authors carried out an extensive full-scale testing scheme using frames of various geometrical configurations, tested under reverse-cyclic lateral loading with/without infill (brick and adobe) or cladding (bağdadi and şamdolma) (Aktas et al. in Earthq Spectra 30(4):1711–1732, 2014a, b). The tests concluded that hımış frames had high energy dissipation capabilities due mostly to nailed connections. Infill/cladding significantly helped improve stiffness and lateral load strength of the frames, and timber type did not seem to make a remarkable impact on the overall behaviour. The current paper, on the other hand, uses test data to calculate capacity/demand ratios based on capacity spectrum method and Eurocode 8 to elaborate more on the performance of “hımış” structures under seismic loading. The obtained results are discussed to draw important conclusions with regards to how frame geometry and infill/cladding techniques affect the overall performance
La enseñanza de las Ciencias Sociales en escuelas primarias. Análisis de los gestos profesionales en clases con el uso de las Aulas Digitales Móviles
A problemática geral que orienta o presente trabalho está relacionada com o uso das Tecnologias da Informação e Comunicação Educativas (TICE) que realizam os professores nas classes de ciências sociais, nas escolas de nível primário. A metodologia utilizada focaliza em três momentos diferentes da situação didática. Em primeiro lugar, uma entrevista ao professor centrada na planificação da sequência didática a implementar; um segundo momento de observação e registro da atividade didática através da técnica de videoscopia y, por último, uma entrevista de autoconfrontação. Na análise, pretende-se demonstrar, de maneira geral como os professores nas classes de ciências sociais usam Aulas Digitais Móveis (ADM). The general problem that guides the work is related to the use of Information Technology and Educational Communication (TICE) that teachers do in Social Sciences classes in primary schools. The methodology used was to make a cut of the reality, to focus on three different moments of a didactic situation. First of all, an interview with the teacher focused on the planning of the didactic sequence to be implemented, a second moment of observation and recording of the didactic activity through the videocopy technique, and for the last time a self-confrontation interview. The analysis aims to show, in a general way, how teachers in social science classes make use of the Digital Mobile Classrooms (ADM). ResumenLa problemática general que orienta el presente trabajo está relacionada con el uso de las Tecnologías de la Información y Comunicación Educativas (TICE) que hacen los maestros en las clases de Ciencias Sociales en escuelas de nivel primario. La metodología utilizada consistió en realizar un recorte de la realidad, focalizando tres diferentes momentos de una situación didáctica. En primer lugar, una entrevista al maestro centrada en la planificación de la secuencia didáctica a implementar, un segundo momento de observación y registro de la actividad didáctica mediante la técnica de videoscopía, y por último una entrevista de autoconfrontación. En el análisis se pretende mostrar, de manera general como los maestros en las clases de ciencias sociales hacen uso de las Aulas Digitales Móviles (ADM).
Facile preparation of nanoparticle based SERS substrates for trace molecule detection
In this work, we demonstrate that a polished Si wafer surface can be converted to possess strong surface-enhanced Raman scattering (SERS) activity by spray coating of polyol synthesized colloidal silver nanoparticles (AgNPs) at as low as 1% surface coverage. The SERS activity assays of substrate surfaces prepared with different production procedures (spray and spin coating) at different surface coverages are realized using population statistics. The resulting Raman enhancement factors (EFs) are discussed with the help of distance-dependent electromagnetic simulations for single particles and dimers. Statistics on the SERS effect and the corresponding EF calculations show that polyol synthesized AgNPs exhibit extremely strong SERS activity with EFs up to 10(8)at as low as 1% surface coverage. We discuss in this work that this is possible due to the distinct properties of polyol synthesized AgNPs such as atomically flat surfaces, sharp edges and corners naturally occurring in this synthesis method, which favor strong plasmonic activity. The method can be generalized to convert virtually any surface into a SERS substrate
Instability of a Noncrystalline NaO2 Film in Na-O2 Batteries: The Controversial Effect of the RuO2 Catalyst
The unique electrochemical and chemical features of
sodium 12oxygen (Na 12O2) batteries distinguish them from the lithium 12
oxygen (Li 12O2) batteries. NaO2 as the main discharge product is unstable
in the cell environment and chemically degrades, which triggers side
products\u2019 formation and charging potential increment. In this study, RuO2
nanoparticles dispersed on carbon nanotubes (CNTs) are used as the
catalyst for Na 12O2 batteries to elucidate the effect of the catalyst on these
complex electrochemical systems. The RuO2/CNT contributes to the
formation of a poorly crystalline and coating-like NaO2 structure during
oxygen reduction reaction, which is drastically different from the
conventional micron-sized cubic NaO2 crystals deposited on the CNT.
Our findings demonstrate a competition between NaO2 and side products\u2019
decompositions for RuO2/CNT during oxygen evolution reaction (OER).
We believe that this is due to the lower stability of a coating-like NaO2
because of its noncrystalline nature and high electrode/electrolyte contact area. Although RuO2/CNT catalyzes the decomposition of side products at a lower potential (3.66 V) compared to CNT (4.03 V), it cannot actively contribute to the main electrochemical reaction of the cell during OER (NaO2 \u2192 Na+ + O2 + e 12) because of the fast chemical degradation of the film NaO2 to the side products. Therefore, tuning the morphology and crystallinity of NaO2 by a catalyst is detrimental for the Na 12O2 cell performance and it should be taken into account for the future applications
Iron Overload in the Liver of 2 Children: Nonalcoholic Steatohepatitis and Juvenile Hemochromatosis
Background: Iron overload disorders are hereditary hemochromatosis and secondary etiologies other than hereditary hemochromatosis. We describe 2 boys presenting with iron overload. Juvenile hemochromatosis and nonalcoholic steatohepatitis (NASH) related iron overload are the genetic and secondary causes, respectively. Observations: Both patients benefited from phlebotomy even if they had different etiologies. Conclusions: In childhood, the diagnosis of iron overload syndromes is crucial because they do not confront us with obvious symptoms and findings. Early initiation of a phlebotomy program can prevent mortality. NASH might lead to iron overload and iron overload might aggravate the clinical course of NASH