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Este estudo tem como objetivo analisar as concepções de licenciandos em Química e em Física sobre a prática profissional e as marcas deixadas pelas disciplinas pedagógicas na sua formação, assim como identificar sinais de mudanças em suas concepções durante a realização do curso de Licenciatura. Para tanto, textos foram produzidos por 54 alunos matriculados em cursos de Licenciatura de duas universidades públicas do estado de São Paulo, nos quais os licenciandos expressaram suas experiências de formação e apontaram elementos que consideram que terão alguma influência em sua atuação profissional. Os textos revelaram que as ideias que os licenciandos carregam são consistentes com muitas das visões e objetivos apresentados em cursos de formação de professores. Nas produções dos estudantes faz-se presente o desejo de compartilhar e promover em seus futuros alunos o interesse pela Química e a Física. Os seus comentários refletiram visões de professores que tiveram no passado, os quais gostariam de imitar, e de outros que não gostariam de ser. Os comentários também tornaram evidente a vontade dos licenciandos em se estabelecerem como professores que se preocupam com seus alunos. Os textos foram analisados segundo a Análise do Discurso de linha francesa, como tem sido divulgada por Eni Orlandi, especialmente a noção de formação discursiva.

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A new species of Trichomycterus is described for the rio Iguaçu drainage in Southern Brazil. Trichomycterus igobi, new species, is readily distinguishable from all other species currently in the genus by its extremely large head (23.8-26.8 % SL), which is proportionally the largest head in any Trichomycteridae. That characteristic plus the relatively deep body result in a very short-bodied overall aspect, the most extremely such case in the genus Trichomycterus. Other diagnostic features that distinguish the new species from most or all of its congeners include a short caudal peduncle (15.4-19.7 % SL); an almost entirely cartilaginous second hypobranchial (with only vestigial ossification); a mesial expanded palatine ossification; a narrow cleithrum, falciform in shape; and the lack of a proximal posterior concavity on the third ceratobranchial. The new species seems to form a monophyletic group with T. stawiarski and other undescribed species (T. sp. C), also endemic to the rio Iguaçu. As putative synapomorphies, the three species share a rigid spine-like morphology of individual procurrent caudal-fin rays, an extended area of dorsal caudal-fin procurrent rays, and numerous branchiostegal rays (ten or eleven).

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This paper describes a new food classification which assigns foodstuffs according to the extent and purpose of the industrial processing applied to them. Three main groups are defined: unprocessed or minimally processed foods (group 1), processed culinary and food industry ingredients (group 2), and ultra-processed food products (group 3). The use of this classification is illustrated by applying it to data collected in the Brazilian Household Budget Survey which was conducted in 2002/2003 through a probabilistic sample of 48,470 Brazilian households. The average daily food availability was 1,792 kcal/person being 42.5% from group 1 (mostly rice and beans and meat and milk), 37.5% from group 2 (mostly vegetable oils, sugar, and flours), and 20% from group 3 (mostly breads, biscuits, sweets, soft drinks, and sausages). The share of group 3 foods increased with income, and represented almost one third of all calories in higher income households. The impact of the replacement of group 1 foods and group 2 ingredients by group 3 products on the overall quality of the diet, eating patterns and health is discussed.

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Avaliou-se a influência exercida pela aquisição de calorias de açúcar sobre a participação calórica dos demais macronutrientes da dieta. As estimativas deste estudo são baseadas em dados da Pesquisa de Orçamentos Familiares realizada no Brasil pelo Instituto Brasileiro de Geografia e Estatística entre julho de 2002 e junho de 2003. Modelos de regressão linear múltiplos foram utilizados para estudar a influência das calorias de açúcar sobre a participação calórica de cada um dos macronutrientes na aquisição domiciliar de alimentos com o controle do valor calórico total da aquisição de alimentos e variáveis sócio-demográficas. Cada caloria adquirida de açúcar eleva em 0,3 caloria a participação de gorduras na aquisição domiciliar de alimentos e diminui em 0,07 a participação de proteínas. Cada caloria de açúcar procedente de alimentos processados aumenta em 1,6 caloria a participação de gorduras e em 0,4 caloria de ácidos graxos saturados e diminui em 0,8 caloria a participação de outros carboidratos que não o açúcar. Os resultados encontrados trazem novas evidências sobre o papel prejudicial do açúcar à saúde humana.

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O financiamento do SUS é regido pelo modelo de federalismo fiscal, pelas regras de partilha do Orçamento da Seguridade Social (OSS), por normas do Ministério da Saúde, e pela Emenda Constitucional nº. 29 (EC-29), que vincula à saúde recursos dos entes federados brasileiros. Discute-se aqui a sustentabilidade do gasto público com saúde no nível municipal. Foram estudados 21 municípios, utilizando-se dados dos balanços municipais. De 1996 a 2006 as receitas correntes gerais per capita subiram 280% acima da inflação acumulada e do Produto Interno Bruto (PIB) nacional, variando conforme o porte do município, o qual também definiu a composição dos orçamentos municipais. Já o orçamento que conforma a base da EC-29 elevou-se bem menos (178%), impondo limitações ao incremento da contrapartida municipal em saúde. Acredita-se que o observado nesses municípios se reproduza em milhares de municípios brasileiros e comprometa a capacidade de investimento municipal em saúde, principalmente a partir de 2008. A situação ainda pode se agravar tendo em vista a extinção da Contribuição Provisória sobre a Movimentação ou Transmissão de Valores e de Créditos e Direitos de Natureza Financeira (CPMF), a tramitação dos Projetos de Lei nº. 306/08 e nº. 233/08, e a recessão mundial, a partir da crise do sistema financeiro norte-americano.

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Objetivou-se descrever e avaliar a influência da renda sobre a participação da alimentação fora do domicílio no Brasil. Utilizaram-se dados coletados pela Pesquisa de Orçamentos Familiares realizada em 2002/2003 (POF 2002/2003), pelo Instituto Brasileiro de Geografia e Estatística. Analisaram-se os registros dos gastos com aquisições de alimentos e bebidas consumidos fora do domicílio. A associação entre a participação da alimentação fora do domicílio e a renda, ajustada para atributos sócio-demográficos, foi estudada por meio de modelos de regressão utilizados para estimação de coeficientes de elasticidade-renda. A alimentação fora do domicílio representou 21% do total dos gastos com alimentação; destaque-se que o incremento de 10% na renda aumentaria em 3% a participação da alimentação fora do domicílio. O efeito da renda sobre a participação da alimentação fora, ainda que sempre positivo, diminui conforme elevação da renda, sendo alto nos domicílios com renda inferior a R$68,70 per capita/mês. Há influência da renda nos gastos com alimentação fora do domicílio, assim a evolução favorável da renda resultará em aumento dessa forma de se alimentar.

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Este artigo descreve uma nova classificação de alimentos baseada na extensão e propósito do processamento industrial usado na sua produção. Três grupos são definidos: alimentos não processados ou minimamente processados (grupo 1), alimentos processados utilizados como ingredientes de preparações culinárias ou pela indústria de alimentos (grupo 2), e produtos alimentícios ultra-processados (grupo 3). O uso da classificação é ilustrado aplicando-a a dados coletados por Pesquisa de Orçamentos Familiares conduzida em 2002/2003 em uma amostra probabilística de 48.470 domicílios brasileiros. A disponibilidade diária foi de 1.792kcal/capita, sendo 42,5por cento de alimentos do grupo 1, 37,5por cento do grupo 2 e 20por cento do grupo 3. A contribuição do grupo 3 aumentou com a renda familiar, correspondendo a um terço do total calórico nos domicílios mais afluentes. Discute-se o impacto sobre a qualidade geral da dieta, padrões de alimentação e condições de saúde que poderia ocorrer com a substituição de alimentos do grupo 1 e ingredientes do grupo 2 por produtos alimentícios do grupo 3

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Background: Polypodium hydriforme is a parasite with an unusual life cycle and peculiar morphology, both of which have made its systematic position uncertain. Polypodium has traditionally been considered a cnidarian because it possesses nematocysts, the stinging structures characteristic of this phylum. However, recent molecular phylogenetic studies using 18S rDNA sequence data have challenged this interpretation, and have shown that Polypodium is a close relative to myxozoans and together they share a closer affinity to bilaterians than cnidarians. Due to the variable rates of 18S rDNA sequences, these results have been suggested to be an artifact of long-branch attraction ( LBA). A recent study, using multiple protein coding markers, shows that the myxozoan Buddenbrockia, is nested within cnidarians. Polypodium was not included in this study. To further investigate the phylogenetic placement of Polypodium, we have performed phylogenetic analyses of metazoans with 18S and partial 28S rDNA sequences in a large dataset that includes Polypodium and a comprehensive sampling of cnidarian taxa. Results: Analyses of a combined dataset of 18S and partial 28S sequences, and partial 28S alone, support the placement of Polypodium within Cnidaria. Removal of the long-branched myxozoans from the 18S dataset also results in Polypodium being nested within Cnidaria. These results suggest that previous reports showing that Polypodium and Myxozoa form a sister group to Bilateria were an artifact of long-branch attraction. Conclusion: By including 28S rDNA sequences and a comprehensive sampling of cnidarian taxa, we demonstrate that previously conflicting hypotheses concerning the phylogenetic placement of Polypodium can be reconciled. Specifically, the data presented provide evidence that Polypodium is indeed a cnidarian and is either the sister taxon to Hydrozoa, or part of the hydrozoan clade, Leptothecata. The former hypothesis is consistent with the traditional view that Polypodium should be placed in its own cnidarian class, Polypodiozoa.

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This article is an introduction to the special issue of Sexuality Research & Social Policy, where we share some of the research of our project, ""Relations among 'race,' sexuality and gender in different local and national contexts."" The goal of this project was to develop broad comparative research on race, sexuality, and gender in Brazil, South Africa, and the USA. New signs of identity and contestation were noted during our research. Given the numerous and important changes which are currently in progress in these interlinked fields, we identified important connections between transformations in the symbolic order and social gains, which cannot necessarily be converted into more widespread decreases in social inequality or which can break apart forms of hierarchization and exclusion. The results of our studies in South Africa and Brazil are the focus of this special issue, given that these two contexts are less well known by the American public.

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Background: High-density tiling arrays and new sequencing technologies are generating rapidly increasing volumes of transcriptome and protein-DNA interaction data. Visualization and exploration of this data is critical to understanding the regulatory logic encoded in the genome by which the cell dynamically affects its physiology and interacts with its environment. Results: The Gaggle Genome Browser is a cross-platform desktop program for interactively visualizing high-throughput data in the context of the genome. Important features include dynamic panning and zooming, keyword search and open interoperability through the Gaggle framework. Users may bookmark locations on the genome with descriptive annotations and share these bookmarks with other users. The program handles large sets of user-generated data using an in-process database and leverages the facilities of SQL and the R environment for importing and manipulating data. A key aspect of the Gaggle Genome Browser is interoperability. By connecting to the Gaggle framework, the genome browser joins a suite of interconnected bioinformatics tools for analysis and visualization with connectivity to major public repositories of sequences, interactions and pathways. To this flexible environment for exploring and combining data, the Gaggle Genome Browser adds the ability to visualize diverse types of data in relation to its coordinates on the genome. Conclusions: Genomic coordinates function as a common key by which disparate biological data types can be related to one another. In the Gaggle Genome Browser, heterogeneous data are joined by their location on the genome to create information-rich visualizations yielding insight into genome organization, transcription and its regulation and, ultimately, a better understanding of the mechanisms that enable the cell to dynamically respond to its environment.

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Background: The cattle tick, Rhipicephalus (Boophilus) microplus, economically impact cattle industry in tropical and subtropical regions of the world. The morphological and genetic differences among R. microplus strains have been documented in the literature, suggesting that biogeographical and ecological separation may have resulted in boophilid ticks from America/Africa and those from Australia being different species. To test the hypothesis of the presence of different boophilid species, herein we performed a series of experiments to characterize the reproductive performance of crosses between R. microplus from Australia, Africa and America and the genetic diversity of strains from Australia, Asia, Africa and America. Results: The results showed that the crosses between Australian and Argentinean or Mozambican strains of boophilid ticks are infertile while crosses between Argentinean and Mozambican strains are fertile. These results showed that tick strains from Africa (Mozambique) and America (Argentina) are the same species, while ticks from Australia may actually represent a separate species. The genetic analysis of mitochondrial 12S and 16S rDNA and microsatellite loci were not conclusive when taken separately, but provided evidence that Australian tick strains were genetically different from Asian, African and American strains. Conclusion: The results reported herein support the hypothesis that at least two different species share the name R. microplus. These species could be redefined as R. microplus (Canestrini, 1887) (for American and African strains) and probably the old R. australis Fuller, 1899 (for Australian strains), which needs to be redescribed. However, experiments with a larger number of tick strains from different geographic locations are needed to corroborate these results.

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We discuss the properties of homogeneous and isotropic flat cosmologies in which the present accelerating stage is powered only by the gravitationally induced creation of cold dark matter (CCDM) particles (Omega(m) = 1). For some matter creation rates proposed in the literature, we show that the main cosmological functions such as the scale factor of the universe, the Hubble expansion rate, the growth factor, and the cluster formation rate are analytically defined. The best CCDM scenario has only one free parameter and our joint analysis involving baryonic acoustic oscillations + cosmic microwave background (CMB) + SNe Ia data yields (Omega) over tilde = 0.28 +/- 0.01 (1 sigma), where (Omega) over tilde (m) is the observed matter density parameter. In particular, this implies that the model has no dark energy but the part of the matter that is effectively clustering is in good agreement with the latest determinations from the large- scale structure. The growth of perturbation and the formation of galaxy clusters in such scenarios are also investigated. Despite the fact that both scenarios may share the same Hubble expansion, we find that matter creation cosmologies predict stronger small scale dynamics which implies a faster growth rate of perturbations with respect to the usual Lambda CDM cosmology. Such results point to the possibility of a crucial observational test confronting CCDM with Lambda CDM scenarios through a more detailed analysis involving CMB, weak lensing, as well as the large-scale structure.

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A large sample of Herbig Ae/Be (HAeBe) candidates, distributed in different Galactic regions south to declination +30 degrees, were identified by the Pico dos Dias Survey (a search for young stellar objects based on IRAS colors). Most of the candidates are nearby or associated with star-forming clouds, but several others are considered isolated objects. Aiming to verify the young nature of 93 HAeBe candidates, we searched for additional information that could be useful to confirm if they are pre-main-sequence (PMS) stars or evolved objects, which coincidentally show similar IRAS colors. By adopting a spectral index that is related to the amount of infrared excess and the shape of the spectral energy distribution, we have classified the sample according to three groups, which are analyzed on the basis of (1) circumstellar luminosity; (2) spatial distribution; (3) optical polarization; (4) near-infrared colors; (5) stellar parameters (mass, age, effective temperature); and (5) intensity of emission lines. Our analysis indicates that only 76% of the studied sample, mainly the group with intermediate to low levels of circumstellar emission, can be more confidently considered PMS stars. The nature of the remaining stars, which are in the other group that contains the highest levels of infrared excess, remains to be confirmed. They share the same characteristics of evolved objects, requiring complementary studies in order to correctly classify them. At least seven objects show characteristics typical of post-asymptotic giant branch or proto-planetary nebulae.

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Context. The formation and evolution of the Galactic bulge and its relationship with the other Galactic populations is still poorly understood. Aims. To establish the chemical differences and similarities between the bulge and other stellar populations, we performed an elemental abundance analysis of alpha- (O, Mg, Si, Ca, and Ti) and Z-odd (Na and Al) elements of red giant stars in the bulge as well as of local thin disk, thick disk and halo giants. Methods. We use high-resolution optical spectra of 25 bulge giants in Baade's window and 55 comparison giants (4 halo, 29 thin disk and 22 thick disk giants) in the solar neighborhood. All stars have similar stellar parameters but cover a broad range in metallicity (-1.5 < [Fe/H] < +0.5). A standard 1D local thermodynamic equilibrium analysis using both Kurucz and MARCS models yielded the abundances of O, Na, Mg, Al, Si, Ca, Ti and Fe. Our homogeneous and differential analysis of the Galactic stellar populations ensured that systematic errors were minimized. Results. We confirm the well-established differences for [alpha/Fe] at a given metallicity between the local thin and thick disks. For all the elements investigated, we find no chemical distinction between the bulge and the local thick disk, in agreement with our previous study of C, N and O but in contrast to other groups relying on literature values for nearby disk dwarf stars. For -1.5 < [Fe/H] < -0.3 exactly the same trend is followed by both the bulge and thick disk stars, with a star-to-star scatter of only 0.03 dex. Furthermore, both populations share the location of the knee in the [alpha/Fe] vs. [Fe/H] diagram. It still remains to be confirmed that the local thick disk extends to super-solar metallicities as is the case for the bulge. These are the most stringent constraints to date on the chemical similarity of these stellar populations. Conclusions. Our findings suggest that the bulge and local thick disk stars experienced similar formation timescales, star formation rates and initial mass functions, confirming thus the main outcomes of our previous homogeneous analysis of [O/Fe] from infrared spectra for nearly the same sample. The identical a-enhancements of thick disk and bulge stars may reflect a rapid chemical evolution taking place before the bulge and thick disk structures we see today were formed, or it may reflect Galactic orbital migration of inner disk/bulge stars resulting in stars in the solar neighborhood with thick-disk kinematics.

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Haplodiploidy results in relatedness asymmetries between colony members of highly eusocial Hymenoptera. As a consequence, queen and reproductive workers are more related to their own sons than to each other's male offspring. Kin selection theory predicts multiple optima in male parentage: either the queen or the workers should produce all the males. Nevertheless, shared male parentage is common in highly eusocial hymenopterans. An inclusive fitness model was used to analyze the effect of the number of reproductive workers on male parentage shared by the queen and laying workers by isolating the male component from an inclusive fitness equation using the equal fitness through male condition for each pairwise combination of the three female classes comprised of the queen, laying workers and non-laying workers. The main result of the theoretical analyses showed that the fraction of males produced by workers increases asymptotically with the number of laying workers at an increasingly diminishing rate, tending to an asymptotic value of 0.67. In addition, as the number of laying workers increases, the share of male parentage converges to that of non-laying workers. The diminishing return effect on male parentage share depending on the number of reproductive workers leads us to expect the number of reproductive workers to be relatively small in a stingless bee colony, even in the absence of productivity costs. The available data confirms this hypothesis, as there is an unusually small number of reproductive workers in stingless bee colonies.