Discurso educativo letrado de professoras alfabetizadoras de diferente perfil pedagógico / Literate educational discourse in the literacy classroom: different teaching styles

RESUMO: A presente pesquisa tem por objetivo qualificar o discurso educativo letrado de professoras alfabetizadoras de diferentes perfis pedagógicos durante as atividades de leitura e comentário de um livro de literatura infantil. No estudo, participaram quatro professoras: duas com perfil educativo interativo/construtivo e duas com perfil diretivo/transmissivo. A análise do discurso educativo colocou em evidência que as professoras de perfil interativo/construtivo fizeram significativamente mais referências às atividades de ensino e aprendizagem desenvolvidas em torno do texto, aos processos cognitivos e linguísticos dos alunos em torno da compreensão e da produção de linguagem a partir do texto e à forma e aos conteúdos do próprio texto. Além disso, formularam maior número de perguntas aos alunos, utilizaram com maior frequência diversos verbos de cognição e linguagem e dedicaram mais tempo à realização das atividades.

ABSTRACT: This research compares the literate discourse used by four early grade teachers with distinct instructional styles during an in-class reading activity with a children's literature book. Four teachers took part in the study, two of them with an interactive/constructive teaching style and the other two with a directive/transmissive style. The results show that the two teachers who follow an interactive/constructive approach more frequently referenced teaching and learning activities around the text, as well as the students' cognitive and linguistic processes, and the form and content of the text itself. Besides that, these two teachers formulated a greater quantity of questions for students, they have used a variety of cognitive and linguistic verbs, and have devoted more time to developing the proposed activities.

Are Prorocentrum hoffmannianum and Prorocentrum belizeanum (DINOPHYCEAE, PROROCENTRALES), the same species? An integration of morphological and molecular data.

The taxonomic assignment of Prorocentrum species is based on morphological characteristics; however, morphological variability has been found for several taxa isolated from different geographical regions. In this study, we evaluated species boundaries of Prorocentrum hoffmannianum and Prorocentrum belizeanum based on morphological and molecular data. A detailed morphological analysis was done, concentrating on the periflagellar architecture. Molecular analyses were performed on partial Small Sub-Unit (SSU) rDNA, partial Large Sub-Unit (LSU) rDNA, complete Internal Transcribed Spacer Regions (ITS1-5.8S-ITS2), and partial cytochrome b (cob) sequences. We concatenated the SSU-ITS-LSU fragments and constructed a phylogenetic tree using Bayesian Inference (BI) and maximum likelihood (ML) methods. Morphological analyses indicated that the main characters, such as cell size and number of depressions per valve, normally used to distinguish P. hoffmannianum from P. belizeanum, overlapped. No clear differences were found in the periflagellar area architecture. Prorocentrum hoffmannianum and P. belizeanum were a highly supported monophyletic clade separated into three subclades, which broadly corresponded to the sample collection regions. Subtle morphological overlaps found in cell shape, size, and ornamentation lead us to conclude that P. hoffmanianum and P. belizeanum might be considered conspecific. The molecular data analyses did not separate P. hoffmannianum and P. belizeanum into two morphospecies, and thus, we considered them to be the P. hoffmannianum species complex because their clades are separated by their geographic origin. These geographic and genetically distinct clades could be referred to as ribotypes: (A) Belize, (B) Florida-Cuba, (C1) India, and (C2) Australia.

Capillary electrophoresis finger print technique (CE-SSCP): an alternative tool for the monitoring activities of HAB species in Baja California Sur Costal.

In Mexican waters, there is no a formal and well-established monitoring program of harmful algal blooms (HAB) events. Until now, most of the work has been focused on the characterization of organisms present in certain communities. Therefore, the development of new techniques for the rapid detection of HAB species is necessary. Capillary electrophoresis finger print technique (CE-SSCP) is a fingerprinting technique based on the identification of different conformers dependent of its base composition. This technique, coupled with capillary electrophoresis, has been used to compare and identify different conformers. The aim of this study was to determine if CE-SSCP analysis of ribosomal RNA (rRNA) gene fragments could be used for a rapid identification of toxic and harmful HAB species to improve monitoring activities along the coasts of Baja California Sur, Mexico.Three different highly variable regions of the 18S and 28S rRNA genes were chosen and their suitability for the discrimination of different dinoflagellate species was assessed by CE-SSCP.The CE-SSCP results obtained for the LSU D7 fragment has demonstrated that this technique with this gene region could be useful for the identification of the ten dinoflagellates species of different genera.We have shown that this method can be used to discriminate species and the next step will be to apply it to natural samples to achieve our goal of molecular monitoring for toxic algae in Mexican waters. This strategy will offer an option to improve an early warning system of HAB events for coastal BCS, allowing the possible implementation of mitigation strategies. A monitoring program of HAB species using molecular methods will permit the analysis of several samples in a short period of time, without the pressure of counting with a taxonomic expert in phytoplankton taxonomy.

Adenosine A(2B) receptor-mediated VEGF induction promotes diabetic glomerulopathy.

Diabetic nephropathy ranks as the most devastating kidney disease worldwide. It characterizes in the early onset by glomerular hypertrophy, hyperfiltration and mesangial expansion. Experimental models show that overproduction of vascular endothelial growth factor (VEGF) is a pathogenic condition for podocytopathy; however the mechanisms that regulate this growth factor induction are not clearly identified. We determined that the adenosine A(2B) receptor (A(2B)AR) mediates VEGF overproduction in ex vivo glomeruli exposed to high glucose concentration, requiring PKCα and Erk1/2 activation. The glomerular content of A(2B)AR was concomitantly increased with VEGF at early stages of renal disease in streptozotocin-induced diabetic rats. Further, in vivo administration of an antagonist of A(2B)AR in diabetic rats blocked the glomerular overexpression of VEGF, mesangial cells activation and proteinuria. In addition, we also determined that the accumulation of extracellular adenosine occurs in glomeruli of diabetic rats. Correspondingly, raised urinary adenosine levels were found in diabetic rats. In conclusion, we evidenced that adenosine signaling at the onset of diabetic kidney disease is a pathogenic event that promotes VEGF induction.

El aprendizaje de los usos expositivos del lenguaje / The acquisition of expository uses of language / A aprendizagem dos usos expositivos da linguagem

Objetivo: Este estudio presenta una descripción del tipo de ayuda lingüística que los adultos les ofrecen a los niños mientras dan explicaciones sobre diversas cuestiones. Metodología: Se analizó una muestra de once minutos de interacción entre un niño pequeño y sus abuelos maternos, pues en el transcurso de estas conversaciones los niños tienen muchas oportunidades para aprender no sólo de los objetos y eventos del mundo sino también del lenguaje que se utiliza para referirse a ellos, para aprender cómo se nombran las realidades y, en algunos casos, cómo se participa en ellas. Resultados: Los adultos ofrecen al niño diferentes recursos discursivos con los que promueven que éste utilice términos que especifiquen las características que diferencian los objetos a los que se está refiriendo, adicione información, organice y clarifique lo que está diciendo. Conclusiones: La descripción de la ayuda que le ofrecen los adultos al niño permitió identificar diferentes recursos discursivos (elicitaciones y reformulaciones) que promueven el desarrollo de explicaciones cada vez más complejas.

Objective: This study offers a description of the kinds of linguistic aids offered by adults while giving explanations to young children about different issues. During the midst of these conversations children have several opportunities to learn, not only from objects and events, but also from the utterances used to refer to them, learning how realities are named after, and in many cases, how to participate in them. Methodology: Through the analysis of eleven minutes of inte-raction between young child and his maternal grandparents. Results: Adults offers young child different discursive ways for helping him to add information, organize and clarify the topic that he is talking about. Conclusions: The results allow to identify different ways that the adults use for helping young child to improve his explanations.

Objetivo: Este estudo apresenta uma descrição do tipo de ajuda lingüística que os adultos lhes oferecem às crianças enquanto dão explicações sobre diversas questões. Metodologia: Se analisou uma amostra de onze minutos de interação entre uma pequena criança e seus avôs maternos, pois no transcurso destas conversações, as crianças têm muitas oportunidades de aprender não só dos objetos e eventos do mundo senão também da linguagem que é utilizado para se referir a eles, para aprender como se nomeiam as realidades, e em alguns casos como se participa delas. Resultados: Os adultos oferecem à criança diferentes recursos discursivos com os que promovem que este utilize termos que especifiquem as características que diferenciam os objetos aos que se esta referindo, adicione informação, organize e clarifique o que esta dizendo. Conclusões: a descrição da ajuda que lhe oferecem os adultos à criança permitiu identificar diferentes recursos discursivos (incitamento e reformulações), que promovem o desenvolvimento de explicações cada vez mais complexas.