Scattered organization of the histone multigene family and transposable elements in Synbranchus

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Chromosomal organization and evolutionary history of Mariner transposable elements in Scarabaeinae coleopterans

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Transcriptional Activity, Chromosomal Distribution and Expression Effects of Transposable Elements in Coffea Genomes

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

Chromosomal mapping of two Mariner-like elements in the grasshopper Abracris flavolineata (Orthoptera: Acrididae) reveals enrichment in euchromatin

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

Correlations among antiangiogenic factors and trace elements in hypertensive disorders of pregnancy

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Transposition burst of mariner-like elements in the sequenced genome of Rhodnius prolixus

Transposable elements (TEs) are widespread in insect´s genomes. However, there are wide differences in the proportion of the total DNA content occupied by these repetitive sequences in different species. We have analyzed the TEs present in R. prolixus (vector of the Chagas disease) and showed that 3.0% of this genome is occupied by Class II TEs, belonging mainly to the Tc1-mariner superfamily (1.65%) and MITEs (1.84%). Interestingly, most of this genomic content is due to the expansion of two subfamilies belonging to: irritans himar, a well characterized subfamily of mariners, and prolixus1, one of the two novel subfamilies here described. The high amount of sequences in these subfamilies suggests that bursts of transposition occurred during the life cycle of this family. In an attempt to characterize these elements, we performed an in silico analysis of the sequences corresponding to the DDD/E domain of the transposase gene. We performed an evolutionary analysis including network and Bayesian coalescent-based methods in order to infer the dynamics of the amplification, as well as to estimate the time of the bursts identified in these subfamilies. Given our data, we hypothesized that the TE expansions occurred around the time of speciation of R. prolixus around 1.4 mya. This suggestion lays on the Transposon Model of TE evolution, in which the members of a TE population that are replicative active are present at multiple loci in the genome, but their replicative potential varies, and of the Life Cycle Model that states that when present-day TEs have been involved in amplification bursts, they share an ancestral copy that dates back to this initial amplification.

Husserl's two notions of completeness: husserl and hilbert on completeness and imaginary elements in mathematics

In this paper I discuss Husserl's solution of the problem of imaginary elements in mathematics as presented in the drafts for two lectures he gave in Göttingen in 1901 and other related texts of the same period, a problem that had occupied Husserl since the beginning of 1890, when he was planning a never published sequel to Philosophie der Arithmetik (1891). In order to solve the problem of imaginary entities Husserl introduced, independently of Hilbert, two notions of completeness (definiteness in Husserl's terminology) for a formal axiomatic system. I present and discuss these notions here, establishing also parallels between Husserl's and Hilbert's notions of completeness. © 2000 Kluwer Academic Publishers.

Correlations of trace elements in breast human tissues: Evaluation of spatial distribution using μ-XRF

The aim of this work is to investigate microscopic correlations between trace elements in breast human tissues. A synchrotron X-ray fluorescence microprobe system (μ-XRF) was used to obtain two-dimensional distribution of trace element Ca, Fe, Cu and Zn in normal (6 samples) and malignant (14 samples) breast tissues. The experiment was performed in X-ray Fluorescence beam line at Laboratório Nacional de Luz Síncrotron (LNLS), Campinas, Brazil. The white microbeam was generated with a fine conical capillary with a 20 μm output diameter. The samples were supported on a XYZ table. An optical microscope with motorized zoom was used for sample positioning and choice the area to be scanned. Automatic two-dimensional scans were programmed and performed with steps of 30 μm in each direction (x, y) on the selected area. The fluorescence signals were recorded using a Si(Li) detector, positioned at 90 degrees with respect to the incident beam, with a collection time of 10 s per point. The elemental maps obtained from each sample were overlap to observe correlation between trace elements. Qualitative results showed that the pairs of elements Ca-Zn and Fe-Cu could to be correlated in malignant breast tissues. Quantitative results, achieved by Spearman correlation tests, indicate that there is a spatial correlation between these pairs of elements (p < 0.001) suggesting the importance of these elements in metabolic processes associated with the development of the tumor.

Aprendendo línguas estrangeiras in-tandem: histórias de identidades

A Pesquisa Narrativa de Clandinin & Connelly (2000) compreende a experiência humana como histórias vividas e contadas. Nesta abordagem qualitativa de pesquisa, os participantes contam histórias e os pesquisadores as recontam e as reconstroem por meio de narrativas acerca das experiências. Tendo este arcabouço metodológico como orientador de nossos procedimentos de pesquisa, neste artigo investigamos nossa experiência compartilhada de aprendizagem in-tandem do português e do italiano - no caso, uma experiência de oito meses por meio de um tandem face-a-face. Neste período, vivenciamos e coletamos dados acerca de nosso processo de aprender a língua um do outro: anotações de campo, mensagens reflexivas de e-mail trocadas durante o período e o conteúdo anotado durante as aulas. Ao reviver nossas histórias vividas durante aquele período, por meio da narrativa aqui apresentada, ressaltamos os elementos de identidade no nosso tandem que acreditamos estarem relacionados à aprendizagem. Também individuamos os elementos desencadeadores de identidade específicos deste contexto de aprendizagem.

Language policy in Brazil: Monolingualism and linguistic prejudice

The purpose of this article is to analyse the linguistic situation in Brazil and to discuss the relationship between Portuguese and the 200 other languages, about 170 indigenous, spoken in the country. It focuses on three points: the historical process of language unification, recent official language policy initiatives, and linguistic prejudice. I examine two manifestations of linguistic prejudice, one against external elements, and the other against supposedly inferior internal elements, pointing out to a common origin: the myth that the Portuguese language in Brazil is characterised by an astonishing unity. © 2004 Kluwer Academic Publishers.

Copy number of P elements, KP/full-sized P element ratio and their relationships with environmental factors in Brazilian Drosophila melanogaster populations

The P transposable element copy numbers and the KP/full-sized P element ratios were determined in eight Brazilian strains of Drosophila melanogaster. Strains from tropical regions showed lower overall P element copy numbers than did strains from temperate regions. Variable numbers of full-sized and defective elements were detected, but the full-sized P and KP elements were the predominant classes of elements in all strains. The full-sized P and KP element ratios were calculated and compared with latitude. The northernmost and southernmost Brazilian strains showed fewer full-sized elements than KP elements per genome, and the strains from less extreme latitudes had many more full-sized P than KP elements. However, no clinal variation was observed. Strains from different localities, previously classified as having P cytotype, displayed a higher or a lower proportion of KP elements than of full-sized P elements, as well as an equal number of the two element types, showing that the same phenotype may be produced by different underlying genomic components of the P-M system.

Losing identity: structural diversity of transposable elements belonging to different classes in the genome of Anopheles gambiae

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Reflexão e identidade profissional do professor de LE: que histórias contam os futuros professores?

Este artigo relata os resultados de um estudo realizado com alunas de graduação em Letras, Português - Língua Estrangeira (Inglês, Espanhol, Italiano, Japonês, Francês e Alemão). Objetivou verificar as metáforas, regras da prática e princípios que as alunas identificaram durante um processo de reflexão sobre suas formações profissionais. Foi possível identificar o impacto desses elementos em seus processos individuais de desenvolvimento de identidades como professoras. O resultado foi um conjunto de histórias biográficas escritas (fontes de experiências) nas quais as participantes se baseavam para constituir suas identidades profissionais como professoras de línguas estrangeiras. Nesses processos, elas puderam construir ligações significativas entre os aspectos teóricos evidenciados nas leituras que realizaram durante o período da pesquisa e os vários eventos marcantes de suas narrativas orais acerca da carreira profissional. A associação dos vários aspectos de suas histórias pessoais às questões teóricas que foram discutidas durante a pesquisa revela processos de construções de identidades profissionais como professoras de línguas estrangeiras.

Evolutionary dynamics of retrotransposable elements Rex1, Rex3 and Rex6 in neotropical cichlid genomes

Background: Transposable elements (TEs) have the potential to produce broad changes in the genomes of their hosts, acting as a type of evolutionary toolbox and generating a collection of new regulatory and coding sequences. Several TE classes have been studied in Neotropical cichlids; however, the information gained from these studies is restricted to the physical chromosome mapping, whereas the genetic diversity of the TEs remains unknown. Therefore, the genomic organization of the non-LTR retrotransposons Rex1, Rex3, and Rex6 in five Amazonian cichlid species was evaluated using physical chromosome mapping and DNA sequencing to provide information about the role of TEs in the evolution of cichlid genomes. Results: Physical mapping revealed abundant TE clusters dispersed throughout the chromosomes. Furthermore, several species showed conspicuous clusters accumulation in the centromeric and terminal portions of the chromosomes. These TE chromosomal sites are associated with both heterochromatic and euchromatic regions. A higher number of Rex1 clusters were observed among the derived species. The Rex1 and Rex3 nucleotide sequences were more conserved in the basal species than in the derived species; however, this pattern was not observed in Rex6. In addition, it was possible to observe conserved blocks corresponding to the reverse transcriptase fragment of the Rex1 and Rex3 clones and to the endonuclease of Rex6. Conclusion: Our data showed no congruence between the Bayesian trees generated for Rex1, Rex3 and Rex6 of cichlid species and phylogenetic hypothesis described for the group. Rex1 and Rex3 nucleotide sequences were more conserved in the basal species whereas Rex6 exhibited high substitution rates in both basal and derived species. The distribution of Rex elements in cichlid genomes suggests that such elements are under the action of evolutionary mechanisms that lead to their accumulation in particular chromosome regions, mostly in heterochromatins. © 2013 Schneider et al.; licensee BioMed Central Ltd.

Investigando o processo ensino-aprendizagem de LE in-tandem: aprendizagem da língua francesa em contexto digital

Pós-graduação em Estudos Linguísticos - IBILCE