953 resultados para Didactic sequences


Relevância:

20.00% 20.00%

Publicador:

Resumo:

AIRES, Kelson R. T. ; ARAÚJO, Hélder J. ; MEDEIROS, Adelardo A. D. . Plane Detection from Monocular Image Sequences. In: VISUALIZATION, IMAGING AND IMAGE PROCESSING, 2008, Palma de Mallorca, Spain. Proceedings..., Palma de Mallorca: VIIP, 2008

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Hebb proposed that synapses between neurons that fire synchronously are strengthened, forming cell assemblies and phase sequences. The former, on a shorter scale, are ensembles of synchronized cells that function transiently as a closed processing system; the latter, on a larger scale, correspond to the sequential activation of cell assemblies able to represent percepts and behaviors. Nowadays, the recording of large neuronal populations allows for the detection of multiple cell assemblies. Within Hebb's theory, the next logical step is the analysis of phase sequences. Here we detected phase sequences as consecutive assembly activation patterns, and then analyzed their graph attributes in relation to behavior. We investigated action potentials recorded from the adult rat hippocampus and neocortex before, during and after novel object exploration (experimental periods). Within assembly graphs, each assembly corresponded to a node, and each edge corresponded to the temporal sequence of consecutive node activations. The sum of all assembly activations was proportional to firing rates, but the activity of individual assemblies was not. Assembly repertoire was stable across experimental periods, suggesting that novel experience does not create new assemblies in the adult rat. Assembly graph attributes, on the other hand, varied significantly across behavioral states and experimental periods, and were separable enough to correctly classify experimental periods (Naïve Bayes classifier; maximum AUROCs ranging from 0.55 to 0.99) and behavioral states (waking, slow wave sleep, and rapid eye movement sleep; maximum AUROCs ranging from 0.64 to 0.98). Our findings agree with Hebb's view that assemblies correspond to primitive building blocks of representation, nearly unchanged in the adult, while phase sequences are labile across behavioral states and change after novel experience. The results are compatible with a role for phase sequences in behavior and cognition.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The Asian subterranean termite, Coptotermes gestroi, originally from northeast India through Burma, Thailand, Malaysia, and the Indonesian archipelago, is a major termite pest introduced in several countries around the world, including Brazil. We sequenced the mitochondrial COII gene from individuals representing 23 populations. Phylogenetic analysis of COII gene sequences from this and other studies resulted in two main groups: (1) populations of Cleveland (USA) and four populations of Malaysia and (2) populations of Brazil, four populations of Malaysia, and one population from each of Thailand, Puerto Rico, and Key West (USA). Three new localities are reported here, considerably enlarging the distribution of C. gestroi in Brazil: Campo Grande (state of Mato Grosso do Sul), Itajai (state of Santa Catarina), and Porto Alegre (state of Rio Grande do Sul).

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The most recent data of the Brazilian Test (BRAZIL, 2005) and of the SAEB (BRAZIL, 2007) have reaffirmed the serious situation of the Brazilian public school, where great part of the students, after to conclude 4º year of basic education, does not present minimum knowledge of reading and writing. In this picture, the situation of the state of Rio Grande do Norte, whose students had presented, in the last evaluation is particularly difficult, the worse performances of the country, in this area. The data also discloses that the failure pertaining to school, closely tied with the failure in the literacy, not only remains, as takes other aspects. In consequence of this picture, the literacy, even so widely argued in the last few decades, still instigates inquiries, as it is the case of this work. Our study got shaped due to reflections, as much to the theorizations to which we had access, as of the emergent questions of ours pedagogical practice. Through the past three decades, the studies in the area of literacy with the purpose to understand the constituent nature of the process, its aspects and its determinative ones has been intensified. The produced knowledge has contributed for the overcoming of the reductionist form as if it thought/thinks, in some contexts - this process. Such statements impel them to reflect concerning what is happening in the school, limiting or making possible the pertaining to school success. With these concerns, we delimit, as focus of study, the teaching action, having the following stunning question: What to make professors, in the context of the public school, to propitiate or hinder the process of literacy of the children? In this direction, our object of study is to make them professors who can propitiate or hinder the process of literacy of the children, in the context of the public school. The objective work to investigate, from practical of professors the teachers, that to make professors related to the literacy process - they can propitiate or hinder the learning of the written language, for the pupils of the public school, at the beginning of the school process. The work if inscribes in the qualitative boarding of research and if it configures as a case study, with characteristics of Research-Action, inspired by the following principles: authenticity and commitment and systematic restitution. For the retraction of the data, they had been used: half-structuralized interview; participant comment; meeting of studies and reflection; register in daily of field. We define as locus of study, a school of public net and, more specifically, a group of the initial years of school process that integrates the cycle of literacy . Of the five invited teachers, only one demonstrated interest in participating of the work. Its group of first year of the First Cycle of basic education is composed for 34 children, with ages between six the nine years. The data constructed by means of the described procedures, as well as its analysis, make possible to identify, between the many aspects and to make that they compose the pedagogical dynamics in the context of classroom, the following categories to make articulated with the literacy process: 1. To make of practical the relative ones to the planning, understood as To make relative: 1,1 distribution of the time-space/routine; 1.2 to the didactic activities and/or sequences and teaching interventions; 1.3 to the organization/election of the contents; 1.4 to the materials/didactic resources and 1.5 to the evaluation. 2. To make relative to the interaction professor-pupil, systemize in: 2.1 attention to the diversity; 2.2 to the affectivity. These to make, in the form as if materialized in the practical one observed, had been reflected, jointly with the teacher, as constituting parts of obstacles to a perspective of literacy. By means of the sharing of the reflections, anchored in theoretical conceptions concerning the practical one of teach-learning and, more specifically, of literacy, we register indications of new meanings of these to make on the part of the teacher in conducting them as providers of learning of its pupils, first purpose of its teaching performance. This finishing, possible synthesis at this moment is, therefore, point of fond and departure for new studies

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Os resíduos vegetais das culturas, ao se decomporem, alteram os atributos químicos do solo e, como consequência, influenciam a produtividade das culturas em sucessão. O objetivo deste trabalho foi avaliar os atributos químicos do solo e a produtividade das culturas de soja, milho e arroz, cultivadas no verão, em sucessão a culturas de inverno em semeadura direta. O experimento foi realizado em Jaboticabal-SP (48 ° 18 ' 58 '' W e 21 ° 15 ' 22 '' S), em um Latossolo Vermelho eutrófico. O delineamento experimental foi em blocos ao acaso, no esquema em faixas, com três repetições. Os tratamentos foram constituídos pela combinação de quatro sequências de culturas de verão (monoculturas de milho e soja e rotações soja/milho e arroz/feijão/algodão) com sete culturas de inverno (milho, girassol, nabo forrageiro, milheto, guandu, sorgo e crotalária). Os cultivos iniciaram-se em 2002. Após o manejo das culturas de inverno e antes da semeadura das culturas de verão do ano agrícola 2006/2007, foram coletadas amostras de solo nas camadas de 0-2,5; 2,5-5,0; 5-10; 10-20; e 20-30 cm. Nas amostras de solo, foram determinados: teores de matéria orgânica, pH, teores de P (resina), K, Ca e Mg trocáveis e acidez potencial (H + Al). As sequências de verão rotação soja/milho e milho em monocultura proporcionaram no solo menores teores de matéria orgânica na camada de 0-10 cm e de P do solo na camada de 0-20 cm. Na sequência de verão arroz/feijão/algodão, maiores teores de K foram proporcionados pelas culturas de inverno crotalária e nabo forrageiro, na camada de 0-10 cm, e milheto, na de 0-2,5 cm. Crotalária, milheto, nabo forrageiro e sorgo, cultivados no inverno, proporcionaram maiores teores de matéria orgânica no solo na camada de 0-30 cm. Maiores teores de P no solo foram proporcionados pela crotalária, na camada de 0-2,5 cm, e pelo nabo forrageiro, na de 0-5 cm. Maiores produtividades de soja, como monocultura de verão, foram obtidas após nabo forrageiro e crotalária e, quando em rotação com milho no verão, após nabo forrageiro, crotalária e milheto. Maiores produtividades de milho foram obtidas após nabo forrageiro, milheto e guandu, e menor produtividade de arroz foi obtida após sorgo.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In this work we present the results of a research that aims to study the chronicle gender produced in a class of native language. The texts were written by students of a high-school class, under the orientation of the teacher who conducted a didactic sequence in order to explore this gender. In our analysis we observed aspect such as the structure of the general structure of the texts, types of speech and linguistic sequences, some mechanisms of textualization and the characteristics of the gender. In order to attain that, we adopted the theoretical presuppositions of Textual Linguistics and of the Socio-discursive Interactionism, grounding the study of texts and gender in Bronckart (2003; 2006) and Koch (2002; 2004). As a background of the Chronicle Gender we used the studies of Coutinho (1987); Moisés (2003); Sá (2005); Bender; Laurito (1993); Melo (1994); Cândido et al. (1992) among others. The corpus, made up of 15 texts, showed that the narrative is the most used linguistic sequence in the producing of the texts, the discursive world prevailing in the narrative and some instances of the world of exposing. As for the gender characteristics, the daily life was used in order to amuse the reader and make him to reflect upon the daily life. Humor, irony, social criticism and colloquial language were also observed in the texts produced by the students. Although some texts presented the characteristics of the gender, explored in the classroom, some were typically school narratives. That make us believe that a work with textual production under the approach of a text gender is viable, but it is not consolidated yet in many schools as the main object of the central teaching of the Portuguese language. This make us defend a better systematization of the teaching contents having as the main point the reading practice and text production in order to contribute for the growing of the students´ discursive potentialities and, therefore, their effective participation in the language social practices

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Paracoccidioides brasiliensis isolates from 10 nine-banded armadillos (Dasypus novemcinctus) were comparable with 19 clinical isolates by sequence analysis of the PbGP43 gene and ribosomal internal transcribed spacer 1 (ITS1) and ITS2 and by random amplified polymorphic DNA. In this original ITS study, eight isolates differed by one or three sites among five total substitution sites.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We examined the types of Epstein-Barr virus-associated nuclear antigen-1 (EBNA-1) gene carboxy (C)-terminal mutations occurring in Hodgkin's disease (HD) and reactive tissues from two different geographic regions. Previously reported EBNA-1 C-terminal region amino acid sequence variants, based on the amino acid at codon 487, include Prototype (P)-ala, which is found in the B95.8-derived prototype virus, P-thr, Variant (V)-leu, V-val, and V-pro. Using polymerase chain reaction (PCR) to amplify portions of the EBNA-1 gene, followed by DNA sequencing, we found a single EBNA-1 gene sequence variant in each tissue, whether reactive or neoplastic and whether from Brazil or the United States. Variant EBNA-1 gene sequences were more common in both neoplastic and non-neoplastic tissues from different geographic areas than the so-called prototype sequence. In the 17 Brazilian HD cases, 4 cases had P-thr variants and 13 had V-leu variants. In the six reactive tissues from Brazil, one had a P-ala variant, two had P-thr variants, and three had V-leu variants. In the 12 American HD cases, 2 had P-ala variants, 6 had P-thr variants, and 4 had V-leu variants. The 11 American reactive tissues included 2 P ala variants, 5 P-thr variants, and 4 V-leu variants. In both countries, there were similar variant EBNA-1 sequences present in normal tissues and HD cases. Compared with the P ala and P-thr cases, the V-leu cases were more likely to have the 30-bp latent membrane protein 1 (LMP1) gene deletion (P = 0.0075). In addition, cases of HD with the V-leu were statistically associated with a substitution of asparagine for glutamine at codon 322 of the C-terminal portion of the LMP1 gene. Our results suggest that any variation in EBNA-1 gene sequence is caused by a polymorphism present in pre-existing viral strains in the underlying population, and not a mutation occurring during oncogenesis. (C) 1999 by the American Society of Hematology.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The nuclear import of simian-virus-40 large T-antigen (tumour antigen) is enhanced via phosphorylation by the protein kinase CK2 at Ser(112) in the vicinity of the NLS (nuclear localization sequence). To determine the structural basis of the effect of the sequences flanking the basic cluster KKKRK, and the effect of phosphorylation on the recognition of the NLS by the nuclear import factor importin-alpha (Impalpha), we co-crystallized non-autoinhibited Impalpha with peptides corresponding to the phosphorylated and non-phosphorylated forms of the NLS, and determined the crystal structures of the complexes. The structures show that the amino acids N-terminally flanking the basic cluster make specific contacts with the receptor that are distinct from the interactions between bipartite NLSs and Impalpha. We confirm the important role of flanking sequences using binding assays. Unexpectedly, the regions of the peptides containing the phosphorylation site do not make specific contacts with the receptor. Binding assays confirm that phosphorylation does not increase the affinity of the T-antigen NLS to Impalpha. We conclude that the sequences flanking the basic clusters in NLSs play a crucial role in nuclear import by modulating the recognition of the NLS by Impalpha, whereas phosphorylation of the T-antigen enhances nuclear import by a mechanism that does not involve a direct interaction of the phosphorylated residue with Impalpha.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Transcribed sequences in the human genome can be identified with confidence only by alignment with sequences derived from cDNAs synthesized from naturally occurring mRNAs. We constructed a set of 250,000 cDNAs that represent partial expressed gene sequences and that are biased toward the central coding regions of the resulting transcripts. They are termed ORF expressed sequence tags (ORESTES). The 250,000 ORESTEs were assembled into 81,429 contigs. of these, 1,181 (1.45%) were found to match sequences in chromosome 22 with at least one ORESTES contig for 162 (65.6%) of the 247 known genes, for 67 (44.6%) of the 150 related genes, and for 45 of the 148 (30.4%) EST-predicted genes on this chromosome. Using a set of stringent criteria to validate our sequences, we identified a further 219 previously unannotated transcribed sequences on chromosome 22. of these, 171 were in fact also defined by EST or full length cDNA sequences available in GenBank but not utilized in the initial annotation of the first human chromosome sequence. Thus despite representing less than 15% of all expressed human sequences in the public databases at the time of the present analysis, ORESTEs sequences defined 48 transcribed sequences on chromosome 22 not defined by other sequences. All of the transcribed sequences defined by ORESTEs coincided with DNA regions predicted as encoding exons by GENSCAN.