Les petites économies d'Amérique Latine et des Caraïbes: croissance, ouverture commerciale et relations inter-régionales

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Chromosome mapping of repetitive sequences in Anostomidae species: Implications for genomic and sex chromosome evolution

Background: Members of the Anostomidae family provide an interesting model system for the study of the influence of repetitive elements on genome composition, mainly because they possess numerous heterochromatic segments and a peculiar system of female heterogamety that is restricted to a few species of the Leporinus genus. The aim of this study was to isolate and identify important new repetitive DNA elements in Anostomidae through restriction enzyme digestion, followed by cloning, characterisation and chromosome mapping of this fragment. To identify repetitive elements in other Leporinus species and expand on studies of repetitive elements in Anostomidae, hybridisation experiments were also performed using previously described probes of LeSpeI repetitive elements. Results: The 628-base pair (bp) LeSpeII fragment was hybridised to metaphase cells of L. elongatus individuals as well as those of L. macrocephalus, L. obtusidens, L. striatus, L. lacustris, L. friderici, Schizodon borellii and S. isognathus. In L. elongatus, both male and female cells contained small clusters of LeSpeII repetitive elements dispersed on all of the chromosomes, with enrichment near most of the terminal portions of the chromosomes. In the female sex chromosomes of L. elongatus (Z2,Z2/W1W 2), however, this repeated element was absent. In the remaining species, a dispersed pattern of hybridisation was observed on all chromosomes irrespective of whether or not they were sex chromosomes. The repetitive element LeSpeI produced positive hybridisations signals only in L. elongatus, L. macrocephalus and L. obtusidens, i.e., species with differentiated sex chromosomes. In the remaining species, the LeSpeI element did not produce hybridisation signals. Conclusions: Results are discussed in terms of the effects of repetitive sequences on the differentiation of the Anostomidae genome, especially with respect to sex chromosome evolution. LeSpeII showed hybridisation patterns typical of Long Interspersed Elements (LINEs). The differential distribution of this element may be linked to sex chromosome differentiation in L. elongatus species. The relationship between sex chromosome specificity and the LeSpeI element is confirmed in the species L. elongatus, L. macrocephalus and L. obtusidens. © 2012 da Silva et al.; licensee BioMed Central Ltd.

Ultra-structural mapping of sugarcane bagasse after oxalic acid fiber expansion (OAFEX) and ethanol production by Candida shehatae and Saccharomyces cerevisiae

Background: Diminishing supplies of fossil fuels and oil spills are rousing to explore the alternative sources of energy that can be produced from non-food/feed-based substrates. Due to its abundance, sugarcane bagasse (SB) could be a model substrate for the second-generation biofuel cellulosic ethanol. However, the efficient bioconversion of SB remains a challenge for the commercial production of cellulosic ethanol. We hypothesized that oxalic-acid-mediated thermochemical pretreatment (OAFEX) would overcome the native recalcitrance of SB by enhancing the cellulase amenability toward the embedded cellulosic microfibrils. Results: OAFEX treatment revealed the solubilization of hemicellulose releasing sugars (12.56 g/l xylose and 1.85 g/l glucose), leaving cellulignin in an accessible form for enzymatic hydrolysis. The highest hydrolytic efficiency (66.51%) of cellulignin was achieved by enzymatic hydrolysis (Celluclast 1.5 L and Novozym 188). The ultrastructure characterization of SB using scanning electron microscopy (SEM), atomic force microscopy (AFM), Raman spectroscopy, Fourier transform-near infrared spectroscopy (FT-NIR), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) revealed structural differences before and after OAFEX treatment with enzymatic hydrolysis. Furthermore, fermentation mediated by C. shehatae UFMG HM52.2 and S. cerevisiae 174 showed fuel ethanol production from detoxified acid (3.2 g/l, yield 0.353 g/g; 0.52 g/l, yield, 0.246 g/g) and enzymatic hydrolysates (4.83 g/l, yield, 0.28 g/g; 6.6 g/l, yield 0.46 g/g). Conclusions: OAFEX treatment revealed marked hemicellulose degradation, improving the cellulases ability to access the cellulignin and release fermentable sugars from the pretreated substrate. The ultrastructure of SB after OAFEX and enzymatic hydrolysis of cellulignin established thorough insights at the molecular level. © 2013 Chandel et al; licensee BioMed Central Ltd.

Chromosomal Mapping of Repetitive DNAs in the Grasshopper Abracris flavolineata Reveal Possible Ancestry of the B Chromosome and H3 Histone Spreading

Supernumerary chromosomes (B chromosomes) occur in approximately 15% of eukaryote species. Although these chromosomes have been extensively studied, knowledge concerning their specific molecular composition is lacking in most cases. The accumulation of repetitive DNAs is one remarkable characteristic of B chromosomes, and the occurrence of distinct types of multigene families, satellite DNAs and some transposable elements have been reported. Here, we describe the organization of repetitive DNAs in the A complement and B chromosome system in the grasshopper species Abracris flavolineata using classical cytogenetic techniques and FISH analysis using probes for five multigene families, telomeric repeats and repetitive C0t-1 DNA fractions. The 18S rRNA and H3 histone multigene families are highly variable and well distributed in A. flavolineata chromosomes, which contrasts with the conservation of U snRNA genes and less variable distribution of 5S rDNA sequences. The H3 histone gene was an extensively distributed with clusters occurring in all chromosomes. Repetitive DNAs were concentrated in C-positive regions, including the pericentromeric region and small chromosomal arms, with some occurrence in C-negative regions, but abundance was low in the B chromosome. Finally, the first demonstration of the U2 snRNA gene in B chromosomes in A. flavolineata may shed light on its possible origin. These results provide new information regarding chromosomal variability for repetitive DNAs in grasshoppers and the specific molecular composition of B chromosomes. © 2013 Bueno et al.

Tracking the evolution of sex chromosome systems in Melanoplinae grasshoppers through chromosomal mapping of repetitive DNA sequences

Background: The accumulation of repetitive DNA during sex chromosome differentiation is a common feature of many eukaryotes and becomes more evident after recombination has been restricted or abolished. The accumulated repetitive sequences include multigene families, microsatellites, satellite DNAs and mobile elements, all of which are important for the structural remodeling of heterochromatin. In grasshoppers, derived sex chromosome systems, such as neo-XY♂/XX♀ and neo-X1X2Y♂/X 1X1X2X2♀, are frequently observed in the Melanoplinae subfamily. However, no studies concerning the evolution of sex chromosomes in Melanoplinae have addressed the role of the repetitive DNA sequences. To further investigate the evolution of sex chromosomes in grasshoppers, we used classical cytogenetic and FISH analyses to examine the repetitive DNA sequences in six phylogenetically related Melanoplinae species with X0♂/XX♀, neo-XY♂/XX♀ and neo-X1X2Y♂/X1X1X 2X2♀ sex chromosome systems. Results: Our data indicate a non-spreading of heterochromatic blocks and pool of repetitive DNAs (C 0 t-1 DNA) in the sex chromosomes; however, the spreading of multigene families among the neo-sex chromosomes of Eurotettix and Dichromatos was remarkable, particularly for 5S rDNA. In autosomes, FISH mapping of multigene families revealed distinct patterns of chromosomal organization at the intra- and intergenomic levels. Conclusions: These results suggest a common origin and subsequent differential accumulation of repetitive DNAs in the sex chromosomes of Dichromatos and an independent origin of the sex chromosomes of the neo-XY and neo-X1X2Y systems. Our data indicate a possible role for repetitive DNAs in the diversification of sex chromosome systems in grasshoppers. © 2013Palacios-Gimenez et al.; licensee BioMed Central Ltd.

Generalização da periodicidade: um estudo sobre Apostrophe et six réflexions de Henri Posseur

Pós-graduação em Música - IA

Diagnóstico da trombose venosa profunda dos membros inferiores, utilizando o modelo clínico de Wells et al. (2003), Dímero-D, Mapeamento Dúplex e avaliação da Proteina C Reativa

Pós-graduação em Bases Gerais da Cirurgia - FMB

Mulher e criança: ambivalência de dois mundos ditados por especialistas em artigos de revistas destinados ao grande público entre os anos de 1940 a 1950

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Educação ou castigo: um estudo sobre mulheres reeducandas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Os entre-lugares do sujeito e da escritura em Arnaldo Antunes

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

A organização para cooperação e desenvolvimento econômico (OCDE) e a política de formação docente no Brasil

A presente tese trata da Política de Formação Docente no Brasil. Tem como objeto de estudo as novas regulações da política de formação docente. O problema de pesquisa se refere à relação existente entre as orientações da Organização para Cooperação e Desenvolvimento Econômico (OCDE) e o processo de regulação das políticas de formação docente no Brasil no período de 2007 a 2010, apresentando as seguintes questões norteadoras: Quais são os interesses e as orientações da OCDE, na área da Educação, no Brasil? Qual é a concepção de educação da OCDE? Qual a concepção de educação que orienta o PDE e o Plano de Metas Compromisso Todos pela Educação? Quais as diretrizes do Plano de Metas Compromisso Todos pela Educação voltadas para a política de formação docente? Quais características das orientações da OCDE estão presentes, na política de formação docente brasileira, no período de 2007 a 2010? Quais são as ações do PDE que se referem à política de formação docente? A lógica de formação docente orientada pela OCDE está sendo seguida pelo governo brasileiro? A investigação partiu da hipótese de que a OCDE interfere e orienta a política de formação docente brasileira o que se manifesta por meio de orientações político-pedagógicas que imputam novas regulações para a condução e materialidade de tal política. Assim, o objetivo da pesquisa consistiu em identificar e analisar a regulação da política de formação docente no Brasil para a educação básica no período de 2007 a 2010 e suas relações com as orientações da OCDE. De modo mais específico buscou-se: analisar a política de formação docente da OCDE; estudar a legislação educacional brasileira relacionada à política de formação docente para os anos iniciais do ensino fundamental; identificar e analisar as relações existentes entre as orientações e perspectivas educacionais da OCDE e a política brasileira de formação docente. O percurso metodológico se deu por meio da pesquisa bibliográfica e documental, bem como realização de entrevistas. Os dados foram analisados por meio da técnica de análise de conteúdo. O estudo realizado sinaliza que a política de formação docente no Brasil vem enfatizando a agenda de desenvolvimento social, econômico e educacional da OCDE. Registra-se a preocupação do governo brasileiro com os professores “eficazes”, com escolas de “sucesso” e o conteúdo nelas transmitidos ocupa centralidade na agenda da política educacional por meio da “cultura dos resultados” via as avaliações internas e externas. Nesta perspectiva a política de formação docente no Brasil vem sendo formulada a partir do contexto de uma nova morfologia do trabalho, que dá maior ênfase à formação dos professores, tendo em vista o papel que estes profissionais podem desempenhar como agentes fundamentais na materialização e no sucesso dessas políticas. O estudo indica que a OCDE orienta as políticas educacionais brasileiras, o que indica que este é um fenômeno relevante de investigação no sentido de ir além da aparência da ideia de que a cooperação e a parceria da Organização com o governo brasileiro são tênues, uma vez que este não fez adesão como país-membro da OCDE.

Mitochondrial DNA mapping of social-biological interactions in Brazilian Amazonian African-descendant populations

ABSTRACT: The formation of the Brazilian Amazonian population has historically involved three main ethnic groups, Amerindian, African and European. This has resulted in genetic investigations having been carried out using classical polymorphisms and molecular markers. To better understand the genetic variability and the micro-evolutionary processes acting in human groups in the Brazilian Amazon region we used mitochondrial DNA to investigate 159 maternally unrelated individuals from five Amazonian African-descendant communities. The mitochondrial lineage distribution indicated a contribution of 50.2% from Africans (L0, L1, L2, and L3), 46.6% from Amerindians (haplogroups A, B, C and D) and a small European contribution of 1.3%. These results indicated high genetic diversity in the Amerindian and African lineage groups, suggesting that the Brazilian Amazonian African-descendant populations reflect a possible population amalgamation of Amerindian women from different Amazonian indigenous tribes and African women from different geographic regions of Africa who had been brought to Brazil as slaves. The present study partially mapped the historical biological and social interactions that had occurred during the formation and expansion of Amazonian African-descendant communities.

Environmental sensitivity index (ESI) mapping of oil spill in the amazon coastal zone: the PIATAM Mar project

A importância do monitoramento ambiental é medida pelos vários casos de derramamentos de óleo ocorridos no mundo durante as últimas três décadas. Isto tem incentivado as empresas e órgãos do governo envolvidos na prevenção e combate a estes acidentes a aperfeiçoarem cada vez mais os métodos, tanto preventivos como corretivos, para a minimização dos danos gerados por acidentes com derramamento de óleo. Este trabalho objetiva contextualizar de forma histórica como os acidentes com derramamento de óleo propiciaram o desenvolvimento de pesquisa tecnológica a partir de parcerias entre empresas de petróleo, agências de governo, universidades e institutos de pesquisa no Brasil, em especial na zona costeira Amazônica. Como resultado, índices de sensibilidade ambiental ao derramamento de óleo (ISA) foram definidos especialmente para a Amazônia costeira, onde processos fluviais e marinhos se encontram na foz do maior rio do mundo, o rio Amazonas. Perspectivas de pesquisa e respostas de emergência a acidentes são apresentadas, a fim de se conservar a diversidade socioambiental da mais importante região tropical do planeta.

Variation, synonymie et equivalence terminologique dans les dictionnaires de médecine monolingues et bilingues

L'existence de variantes et de quasi-synonymes terminologiques dans un même domaine est une réalité constatée par plusieurs études en terminologie descriptive. Les termes techniques/scientifiques coexistent avec les variantes populaires, régionales, orthographiques, syntaxiques et autres. En analysant certains dictionnaires terminologiques spécialisés en médecine, nous avons remarqué que les variantes et les quasi-synonymes ne font pas l'objet d'un traitement terminographique et ne participent donc pas de la nomenclature. Il est ainsi difficile à quelqu'un qui ne connaît que l'une de ces unités terminologiques d'entrer dans ces ouvrages et d'avoir accès à l'information désirée. Dans cet article nous faisons une analyse du traitement terminographique donné aux variantes et aux quasi-synonymes terminologiques dans certains dictionnaires de médecine, plus spécifiquement dans certains ouvrages de dermatologie, et présentons une proposition d'organisation du système de renvois qui prend en considération l'existence de plusieurs termes pour désigner un même concept.

A memória do mundo e a confiança em Yves Bonnefoy

Cette communication prétend parcourir quelques poèmes de Les planches courbes (2001) d’Yves Bonnefoy à partir de l’opposition entre mémoire et oubli. Cette réflexion se trouve esquissée dans l’essai “Sous l’horizon du langage” du livre homonyme, lorsqu’il affirme que la poésie est “ce qui, dans l’espace des mots, notre monde, a mémoire du surcroît de ce qui est sur ses représentations” (2002 : 8). Il s’agit d’une mémoire établie moins à partir d’un lieu perdu que retrouvé. Ce à elle que le moi se confie: dans le “oui”, dans la paix, ces deux mots qui apparaissent dans ses livres les plus récents. Le poète apporterait une confiance qui reprendrait, d’une certaine façon, ce que Paul Ricoeur a caractérisé comme le sens des inscriptions-affections: “elles seraient le dépositaire de la signification la plus dissimulée, mais la plus originaire du verbe “demeurer”, synonyme de “durer”. Dans Les planches courbes, il s’agit également d’une mémoire de l’enfance et des mythes. Ce sont des événements qui prennent place dans un temps primordial. Espoir/confiance, donc, de remonter à une force plus ancienne de la langue, de soi-même, de l’être, de ses rapports. Remonter à une unité dans le simple, en reliant une appréhension du monde et de soi-même dans un acte de suffisance, dans lequel celui-ci se conjugue avec une espèce de dépossession: de l’idée, du concept, de l’image.