4,624 research outputs found

    Evolution and Maintenance of Plumage Polymorphism: the case of the Red-footed booby (Sula sula)

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    The red-footed booby (Sula sula) is considered one of the most polymorphic seabirds, with three recognized major adult plumage types: (1) white; (2) white-tailed brown; and (3) brown, and several degrees of intermediates. The ratio of these color morphs varies among populations, with the white morph typically predominating. However, there are a few populations that present an inversed ratio of color morphs, such as Isla Europa in the Indian Ocean and the Galapagos archipelago, with the white-tailed brown or brown morphs predominating. I studied natural populations of red-footed boobies from three geographic locations, namely, the Galapagos archipelago, Johnston Atoll in the Pacific Ocean, and the Fernando de Noronha archipelago in the South Atlantic Ocean, to investigate the genetic basis of plumage polymorphism as well as possible mechanisms maintaining the polymorphism and variation in the ratios of color morphs. To determine the genetic basis of the polymorphism, I investigated the role played by the candidate locus Melanocortin-1 receptor (MC1R). By examining alleles in the MC1R locus in the context of phylogeny of the Sulidae family, I investigate the scope of involvement of the MC1R locus in determining the different plumage colors and patterns among the ten species in this family. Several potential mechanisms maintaining the polymorphism and the differential ratio of color morphs among locations were evaluated; both selective and neutral mechanisms were explored, such as non-random mating and limited gene flow, as well as historical evolutionary events such as founder effect and bottleneck events

    Several biases in evaluation process of professors by undergraduate students

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    The evaluation of the teaching process uses questionnaires applied to the students, giving them the power of be anonymous in their responses. However, if at the end of the course some students get low grades, at the moment of their responses to the questionnaires they can have an attitud of revenge against the teacher, manifested by bad evaluation to the teachers. There are other situations that interfere with students responses leading to biases in evaluation process. We reviewed factors that interfere in the teacher evaluation through questionnaires causing biases and, we also tryed to find alternatives to diminish biases in evaluation. We search original articles and reviews in web sites databases about biases in professor evaluation process and comments about avoid these biases. We also conducted a manual search for relevant articles in the reference lists of articles. Several factors can be biases in teachig evaluation proccess as feeling of revenge, more difficult course, younger students and gender male students evaluators. Non-white teachers, female teachers, older teachers, non-charism teachers, non-good look teachers also get lower grades. Teacher evaluations through questionnaires must be viewed with caution due to several biases.  Since questionnaires are difficult to be replaced in the evaluation of teachers, we discuss alternatives in order to avoid injustice to the teachers

    Tradução comentada de contos de Desmond Hogan : Três Contos do Exílio

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    Dissertação (mestrado)—Universidade de Brasília, Instituto de Letras, Departamento de Línguas Estrangeiras e Tradução, Programa de Pós-Graduação em Estudos da Tradução, 2017.A presente dissertação de mestrado, partindo de uma visada literária que vê a tradução, simultaneamente, como parte do corpo maior da literatura mundial e como fazer textual e reescritura, tem como tema a tradução comentada de contos de Desmond Hogan, escritor irlandês contemporâneo ainda não traduzido no Brasil. Os três contos selecionados tratam da questão do exílio e da diáspora, de importância central na literatura irlandesa. O trabalho começa por apresentar o autor e passa em seguida ao exame do contexto irlandês que condicionou tanto a temática quanto a forma das obras de Hogan, que é em seguida situado na história do espaço literário irlandês moderno, desde as primeiras manifestações nacionalistas e o alto modernismo de Joyce e Beckett até os dias de hoje. Na segunda parte do trabalho, apresento minha tradução dos três contos, em formato bilíngue. Em meu comentário à tradução, tento entrelaçar as dimensões de fazer e reflexão, usando para tal as ideias colocadas por Henri Meschonnic em sua poética do traduzir, identificando aspectos da poética de Desmond Hogan - semântica, ritmo e pontuação - e apontando a maneira com que esses elementos foram ecoados na tradução. Em seguida, comento minha tradução de passagens selecionadas.This master's degree thesis takes a literary standpoint that places translation within the greater body of world literature, and views it as the rewriting of a literary work. Its theme is the commented translation of three short-stories by Desmond Hogan, a contemporary Irish writer still unpublished in Brazil. All three short-stories deal with the issues of exile and diaspora, of crucial importance in Irish literature. I start out by introducing the author, and proceed to describe the Irish context that conditioned both the themes and the formal aspects of Hogan's work. The author is then located within the history of the modern Irish literary space, from the early nationalistic manifestations and the high modernism of Joyce and Beckett until the present. In the second part I present my translation of the three short-stories in a bilingual format. In my commentaries, I try to interweave experience and reflection by using the ideas of Henri Meschonnic, as presented in his poetics of translation. I identify different aspects of Hogan's poetics - semantics, rhythm and punctuation - and indicate the manner in which these elements were echoed in the translated text. Lastly, I comment my translation of selected passages

    On the value of popular crystallographic databases for machine learning prediction of space groups

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    Predicting crystal structure information is a challenging problem in materials science that clearly benefits from artificial intelligence approaches. The leading strategies in machine learning are notoriously data-hungry and although a handful of large crystallographic databases are currently available, their predictive quality has never been assessed. In this article, we have employed composition-driven machine learning models, as well as deep learning, to predict space groups from well known experimental and theoretical databases. The results generated by comprehensive testing indicate that data-abundant repositories such as COD (Crystallography Open Database) and OQMD (Open Quantum Materials Database) do not provide the best models even for heavily populated space groups. Classification models trained on databases such as the Pearson Crystal Database and ICSD (Inorganic Crystal Structure Database), and to a lesser extent the Materials Project, generally outperform their data-richer counterparts due to more balanced distributions of the representative classes. Experimental validation with novel high entropy compounds was used to confirm the predictive value of the different databases and showcase the scope of the machine learning approaches employed.publishedVersio

    Estratégias de regulação territorial e uso de recursos comuns: desafios à gestão compartilhada na Reserva de Desenvolvimento Sustentável Amanã – AM

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    Partindo da observação participante desenvolvida em reuniões comunitárias com a presença de instituições de gestão que atuam na Reserva de Desenvolvimento Sustentável Amanã (RDSA), no Médio Solimões, Amazonas, este texto aborda os desafios da gestão compartilhada a partir de conflitos associados às situações de disputas entre moradores da Unidade de Conservação, indígenas e não indígenas, pelo controle ao acesso e uso de recursos pesqueiros em interface à demanda de demarcação de Terra Indígena. Nesse contexto, entrevistas livres foram conduzidas com lideranças e moradores do setor Joacaca e Boa União para compreender as motivações diversas do conflito, destacando-se aqui aquelas relacionadas aos interesses e estratégias para assegurar o controle exclusivo de recursos em um território já protegido e de uso concedido ao coletivo. O interesse da descrição e análise dos casos visa a conhecer de que formatais conflitos articulam-se aos modos diferenciados localmente de ordenar uso de recursos e regular territórios, identificando, com isso, efeitos e desafios gerados a instrumentos e práticas de gestão compartilhadas.Starting from the participant observation developed in community meetings with the presence of management institutions that work in the Amanã Sustainable Development Reserve (RDSA), in the Middle Solimões, Amazonas, this text addresses the challenges of shared management from conflicts associated with dispute situations between residents of the Conservation Unit, indigenous and non-indigenous, for the control of access and use of fishing resources in interface with the demand for demarcation of Indigenous Land. In this context, free interviews were conducted with leaders and residents of the Joacaca and Boa União sectors to understand the different motivations of the conflict, highlighting those related to interests and strategies to ensure exclusive control of resources, in an already protected and used territory given to the collective. The interest in the description and analysis of the cases aims to know how such conflicts are linked to locally differentiated ways of ordering resource use and regulating territories, thus identifying effects and challenges generated by shared management tools and practices

    Fósforo, nitrogênio, lignina, celulose e polifenóis em amostras de serrapilheira foliar de Neea macrophylla, Cecropia palmata e Casearia arborea no Nordeste do Estado do Pará.

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    A necessidade de se conhecer a dinâmica de decomposição da serrapilheira (liteira) foliar de espécies potencialmente acumuladoras de fósforo (P) como Neea macrophylla e Cecropia palmata ao longo do tempo, é fundamental na seleção de mulch para a tecnologia de preparo de área para plantio denominada slash and mulch adotada em alguns sistemas agrícolas a Nordeste do Estado do Pará. Com o intuito de caracterizar quantitativamente e temporalmente as Taxas de Incremento de P e N ao longo do processo inicial de decomposição da liteira foliar das espécies estudadas correlacionando com as concentrações iniciais de lignina, celulose e polifenóis, este experimento foi então desenvolvido alocando-se bolsas de decomposição sobre a serrapilheira de uma floresta secundária no Município de Igarapé-Açú, estado do Pará. Os resultados indicaram uma alta correlação (r=-0,82) entre a concentração de polifenóis iniciais no liteira e a perda de biomassa ao longo de 210 dias; a liberação de fósforo (P) durante o processo de decomposição foi determinada em parte pelas concentrações de lignina iniciais (r=-0,54) mas sobretudo de celulose (r=-0,73) e as concentrações de N-NH4 na liteira foliar ao final do período de observação mostraram dependência da concentração inicial de lignina. Neea macrophylla foi a espécie que perdeu mais rapidamente biomassa para o solo mostrando ser uma espécie importante no processo de ciclagem de fósforo em ambientes com deficiência

    Reabsorção de nutrientes por espécies arbóreas acumuladoras de fósforo na Amazônia: influência na qualidade da serrapilheira.

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    A importância de se conhecer as concentrações e os estoques de nutrientes como o fósforo (P) e o nitrogênio (N) na serrapilheira (liteira) produzida por espécies potencialmente acumuladoras de fósforo em florestas secundárias cujos solos são deficientes neste nutriente deve-se à necessidade de se identificar mulch de qualidade para a tecnologia de preparo de área do tipo chop and mulch recentemente praticada pela Agricultura Itinerante do Nordeste do Estado do Pará. Dessa forma, os teores e os estoques de fósforo e nitrogênio encontrados na serrapilheira foliar de Neea macrophylla foram superiores aos de Cecropia palmata e Casearia arborea, sugerindo que o melhor litter seria o produzido por Neea. Contudo, é Cecropia palmata a espécie com maior capacidade de retranslocação de fósforo das folhas senescentes para as folhas maduras, sugerindo uma estratégia de economia do nutriente em condição de estresse natural. Quanto ao nitrogênio, as retranslocações foram muito baixas para as três espécies, sinalizando que este nutriente parece não estar sendo limitante

    Fallopian tube origin of supposed ovarian high‐grade serous carcinomas

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    INTRODUCTION: Serous carcinomas are the most frequent histologic type of ovarian and peritoneal cancers, and can also be detected in the endometrium and fallopian tubes. Serous carcinomas are usually high-grade neoplasms when diagnosed, yet the identification of an associated precursor lesion remains challenging. Pathological examination of specimens obtained from prophylactic bilateral salpingo-oophorectomies that were performed for patients harboring BRCA1/2 mutations suggests that high-grade serous carcinomas may arise in the fallopian tubes rather than in the ovaries. OBJECTIVE: To investigate the presence and extent of fallopian tube involvement in cases of serous pelvic carcinomas. METHODS: Thirty-four cases of serous pelvic carcinoma with clinical presentations suggesting an ovarian origin were analyzed retrospectively. Histologic samples of fallopian tube tissues were available for these cases and were analyzed. Probable primary site, type of tubal involvement, tissues involved in the neoplasia and vascular involvement were evaluated. RESULTS: Fallopian tube involvement was observed in 24/34 (70.6%) cases. In 4 (11.8%) of these cases, an intraepithelial neoplasia was present, and therefore these cases were hypothesized to be primary from fallopian tubes. For an additional 7/34 (20.6%) cases, a fallopian tube origin was considered a possible primary. CONCLUSIONS: Fallopian tubes can be the primary site for a subset of pelvic high-grade serous carcinomas
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