881 resultados para tegumento seminal


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A Tecnologia da Informação e Comunicação (TIC) permite que as empresas realizem suas operações de maneira mais eficiente, alavanquem suas estratégias de negócio e tragam assim as vantagens competitivas necessárias para o sucesso e perenidade do empreendimento. É constante nos meios acadêmicos e empresariais o questionamento sobre o valor que a TIC efetivamente traz ao negócio dados os altos investimentos necessários para sua aquisição, implementação e manutenção. A partir da proposição seminal de Markowitz sobre a Análise de Portfólio (que tratou especificamente dos investimentos financeiros), outros autores estenderam este conceito para realizar a avaliação, seleção e priorização de projetos, criando o que atualmente se denomina de Gestão de Portfólio de Projetos. A Gestão de Portfólio de Projetos, por sua vez, foi posteriormente estendida para os projetos de TIC e foi proposta então a abordagem de Gestão de Portfólio de Projetos de TIC. Além das questões meramente técnicas ou metodológicas, vários fatores organizacionais estão presentes na execução deste processo e podem influenciá-lo. Este trabalho identifica os fatores organizacionais que envolvem a Gestão de Portfólio de Projetos de TIC e analisa as influências que estes fatores trazem sobre o processo citado. A pesquisa é de natureza qualitativa, de caráter exploratório e descritivo e é operacionalizada através da realização de estudos de caso múltiplos em 3 (três) bancos médios comerciais brasileiros. A principal contribuição deste trabalho é a proposição de uma estrutura conceitual que representa os diversos fatores organizacionais que influenciam a Gestão de Portfólio de Projetos de TIC em uma organização. Há indícios de que os fatores organizacionais têm grande influência sobre este processo dadas as respostas obtidas nas entrevistas com os profissionais dos bancos analisados.

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Esta tese é composta por três ensaios sobre o mercado de crédito e as instituições que regem bancarrota corporativa. No capítulo um, trazemos evidências que questionam a ideia de que maiores níveis de proteção ao credor sempre promovem desenvolvimento do mercado de crédito. Desde a publicação dos artigos seminais de La Porta et al (1997,1998), a métrica de proteção ao credor que os autores propuseram -- o índice de proteção ao credor -- tem sido amplamente utilizada na literatura de Law and Finance como variável explicativa em modelos de regressão linear em forma reduzida para determinar a correlação entre proteção ao credor e desenvolvimento do mercado de crédito. Neste artigo, exploramos alguns problemas com essa abordagem. Do ponto de vista teórico, essa abordagem geralmente supõe uma relação monotônica entre proteção ao credor e expansão do crédito. Nós apresentamos um modelo teórico para um mercado de crédito com seleção adversa em que um nível intermediário de proteção ao credor é capaz de implementar equilíbrios first best. Este resultado está de acordo com diversos outros artigos teóricos, tanto em equilíbrio geral quanto em equilíbrio parcial. Do ponto de vista empírico, tiramos proveito das reformas realizadas por alguns países durante as décadas de 1990 e 2000 para implementar uma estratégia inspirada na literatura de treatment effects e estimar o efeito sobre o valor de mercado e sobre a dívida de: i) permitir automatic stay a firmas em recuperação; e ii) conceder aos credores o direito de afastar os administradores. Os resultados que obtivemos apontam para um impacto positivo de automatic stay sobre todas as variáveis que dependem do valor de mercado da firma. Não encontramos efeito sobre dívida, e não encontramos efeitos significativos do direito de afastar administradores sobre valor de mercado ou dívida. O capítulo dois avalia as consequências empíricas de uma reforma na lei de falências sobre um mercado de crédito pouco desenvolvido. No início de 2005, o Congresso Nacional brasileiro aprovou uma nova lei de falências, a lei 11.101/05. Usando dados de firmas brasileiras e não-brasileiras, nós estimamos, usando dois modelos diferentes, o efeito da reforma falimentar sobre variáveis contratuais e não-contratuais de dívida. Ambos os modelos produzem resultados similares. Encontramos um aumento no volume total de dívida e na dívida de longo prazo, e uma redução no custo de dívida. Não encontramos efeitos significativos sobre a estrutura de propriedade da dívida. No capítulo três, desenvolvemos um modelo estimável de equilíbrio em search direcionado aplicado ao mercado de crédito, modelo este que pode ser usado para realizar avaliações ex ante de mudanças institucionais que afetem o crédito (como reformas em leis de falência). A literatura em economia há muito reconhece uma relação causal entre instituições (como leis e regulações) e desenvolvimento dos mercados financeiros. Essa conclusão qualitativa é amplamente reconhecida, mas há pouca evidência de sua importância quantitativa. Com o nosso modelo, é possível estimar como contratos de dívida mudam em resposta a mudanças nos parâmetros que descrevem as instituições da economia. Também é possível estimar o impacto sobre investimentos realizados pelas firmas, bem como caracterizar a distribuição do tamanho, idade e produtividade das firmas antes e depois da mudança institucional. Como ilustração, realizamos um exercício empírico em que usamos dados de firmas brasileiras para simular o impacto de variações na taxa de recuperação de créditos sobre os valores médios e totais de dívida e capital das firmas. Encontramos dívida crescente e capital quase sempre também crescente na taxa de recuperação.

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Desde o início da história taxonômica de Relbunium, muitos foram os trabalhos que enfatizaram sua autonomia e posição taxonômica. Atualmente, alguns estudos sugerem que as espécies pertencentes a Relbunium devam ser incluídas em uma seção do gênero Galium. Porém, recentes estudos moleculares na tribo Rubieae, destacam Galium como um grupo parafilético, e Relbunium como um gênero independente e monofilético. O problema taxonômico referente a Galium e Relbunium é de difícil solução, devido à ausência de estudos que integrem caracteres morfológicos, ecológicos e moleculares. No presente trabalho objetivou-se adicionar informações para o conhecimento básico das espécies de Relbunium e Galium para o sul do Brasil, a partir de caracteres morfológicos e moleculares, buscando responder a seguinte questão: “Relbunium pode ser considerado um gênero ou apenas uma seção dentro de Galium?”. Para atingir os objetivos, foi analisada a morfologia das espécies, com ênfase nas folhas, flores e frutos para duas espécies de Galium e treze de Relbunium: G. latoramosum, G. uruguayense, R. equisetoides, R. gracillimum, R. hirtum, R. humile, R. humilioides, R. hypocarpium, R. longipedunculatum, R. mazocarpum, R. megapotamicum, R. nigro-ramosum, R. ostenianum, R. richardianum e R. valantioides. Chaves de identificação foram geradas a partir dos resultados das análises morfológicas. As folhas foram analisadas quanto à forma, ápice, padrão de venação, tricomas, estômatos, distribuição de idioblastos secretores e vascularização do hidatódio. Esses caracteres não evidenciaram a separação entre os gêneros, auxiliando apenas na individualização das espécies. A morfologia das flores e frutos auxiliou na diferenciação dos gêneros e espécies estudadas. As flores são comumente bispóricas, a exceção de G. latoramosum. Brácteas involucrais, ausentes em Galium, estão presentes nas espécies de Relbunium, de duas a quatro; nesse gênero há presença de antopódio, ausente em Galium. A corola possui tricomas glandulares unicelulares na face adaxial, e na face abaxial os tricomas, quando presentes, são simples e idioblastos secretores estão presentes apenas em R. gracillimum. O androceu tem quatro estames alternipétalos e exsertos, com anteras dorsifixas e tetrasporangiadas, de deiscência longitudinal. O ovário é ínfero, bicarpelar, bilocular, com um rudimento seminal anátropo e unitegumentado por lóculo. O desenvolvimento dos frutos, a estrutura do pericarpo e da testa foram descritos. Os frutos são do tipo baga, em R. gracillimum e R. hypocarpium, ou esquizocarpo, nas demais espécies. A consistência do pericarpo pode variar de carnosa, nos frutos do tipo baga, a levemente seca, nos frutos esquizocarpos. Entre as espécies, observou-se uma variação com relação ao exocarpo, que pode ser liso, piloso ou com idioblastos secretores. A testa é constituída por apenas uma camada de células, que em R. hypocarpium mostra-se descontínua. Além das descrições morfológicas, foram realizados estudos moleculares das espécies, através do seqüenciamento de fragmentos do DNA nuclear (ITS) e plastidial (trnL-F). A partir dos resultados obtidos formam elaborados cladogramas com base nos dados morfológicos e moleculares. O cladograma construído a partir dos dados morfológicos (vegetativos e reprodutivos) evidenciou a distinção dos dois gêneros, ou seja, sustenta Relbunium como táxon independente. Nesse cladograma observa-se que a VI presença ou ausência de brácteas foi determinante, e proporcionou a separação dos gêneros. A uniformidade dos caracteres morfológicos vegetativos entre as espécies auxiliou apenas na distinção das espécies de Relbunium. Com relação aos dados moleculares, os fragmentos de DNA utilizados mostraram-se pouco informativos. A análise do fragmento ITS, em especial, contribuiu para confirmação da relação entre algumas espécies (R. hirtum e R. ostenianum, e R. humile e R. mazocarpum). A análise combinada dos dados morfológicos e moleculares não caracterizou Relbunium como um clado monofilético, sendo sua manutenção não sustentada, isso, principalmente, devido à falta de diferenças moleculares entre as espécies. Conclui-se que para o grupo em questão as análises morfológicas, das folhas, flores e frutos, foram suficientes para destacar Relbunium como um gênero autônomo e monofilético na tribo Rubieae.

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This paper approaches the strategy in business management and aimed at identifying and outlining the interests and commitment of stakeholders in strategic resources management concerning production and implementation of wind turbine equipment of a Brazilian wind power company and also verifying if internal and external results deriving from such activities were sustainable, taking as main reference seminal publications and periodicals relevant to the research point that discuss the Resource Theory, Stakeholders and Sustainability. An analysis was carried out to assess how stakeholders, beyond the temporal context, intermediated the composition, development and management of the organization´s resources, as well as the social, environmental and economic results obtained from resources management in the production and supply of wind turbines to a Wind Power Plant located in the State of Ceara, in order to portray that Brazil sustainability can be an important competitive advantage source that creates value for shareholders and the community (Hart & Milstein, 2003). The strategy herein applied was the qualitative investigation using a single study case, which allowed for the thorough examination of an active organization operating in the Brazilian industry of wind power and also the resources used in the production and implementation of wind turbines supplied to the a Wind Power Plant in Ceara. Considering the content analysis and the triangulation principle, three qualitative data collection methods were applied to identify and characterize stakeholders’ interest and commitment in resource management of the organization operating in the Brazilian wind power industry, as follows, semistructured deep interview with managers of tactic-strategic level and analysts of organization´s value chain nine activities, analysis of public internal and external documents; and analysis of audio-visual material. Nonetheless, to identify the internal and external economic, social and environmental results of implementation and supply of wind turbines to the Wind Power Plant in Ceara, semistructured interviews were also carried out with the residents of the region. Results showed the BNDES (Brazilian Development Bank) and the organization head office were the stakeholders who exerted the strongest influence on resources related to production and implementation of the aerogenerator product at Trairi Wind Plant in Ceara. Concerning the organization resources, at the current stage of the Brazilian Wind Industry ,although the brand, reliability and reputation of the organization under study were valuable esources, rare, hard to imitate and exploited by the organization, it was noticed that opposed to RBV, they did not actually represent a source of competitive advantage . For the local community the social, economic and environmental results related to the wind turbines implementation were more positive than negative, despite the fact that the productive process caused negative environmental impacts such as the high emission of CO2 to transport wind turbines components to Trairi Wind Power Plant.

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In June 2014 Brazil hosted the FIFA World Cup and in August 2016 Rio de Janeiro hosts the Summer Olympics. These two seminal sporting events will draw tens of thousands of air travelers through Brazil’s airports, airports that are currently in the midst of a national modernization program to address years of infrastructure neglect and insufficient capacity. Raising Brazil’s major airports up to the standards air travelers experience at major airports elsewhere in the world is more than just a case of building or remodeling facilities, processes must also be examined and reworked to enhance traveler experience and satisfaction. This research paper examines the key interface between airports and airline passengers—airport check-in procedures—according to how much value and waste there is associated with them. In particular, the paper makes use of a value stream mapping construct for services proposed by Martins, Cantanhede, and Jardim (2010). The uniqueness of this construct is that it attributes each activity with a certain percentage and magnitude of value or waste which can then be ordered and prioritized for improvement. Working against a fairly commonly expressed notion in Brazil that Brazil’s airports are inferior to the airports of economically advanced countries, the paper examines Rio’s two major airports, Galeão International and Santos Dumont in comparison to Washington D.C.’s Washington National and Dulles International airports. The paper seeks to accomplish three goals: - Determine whether there are differences in airport passenger check-in procedures between U.S. and Brazilian airports in terms of passenger value - Present options for Brazilian government or private sector authorities to consider adopting or implementing at Brazilian airports to maximize passenger value - Validate the Martins et al. construct for use in evaluating the airport check-in procedures Observations and analysis proved surprising in that all airports and service providers follow essentially the same check-in processes but execute them differently yet still result in similar overall performance in terms of value and waste. Although only a few activities are categorized as completely wasteful (and therefore removed in the revised value stream map of check-in activities), the weighting and categorization of individual activities according to their value (or waste) presents decision-makers a means to prioritize possible corrective actions. Various overall recommendations are presented based on this analysis. Most importantly, this paper demonstrates the viability of using the construct developed by Martins et al to examine airport operations, as well as its applicability to the study of other service industry processes.

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This article proposes an alternative methodology for estimating the effects of non-tariff measures on trade flows, based on the recent literature on gravity models. A two-stage Heckman selection model is applied to the case of Brazilian exports, where the second stage gravity equation is theoretically grounded on the seminal Melitz model of heterogeneous firms. This extended gravity equation highlights the role played by zero trade flows as well as firm heterogeneity in explaining bilateral trade among countries, two factors usually omitted in traditional gravity specifications found in previous literature. Last, it also proposes a economic rationale for the effects of NTM on trade flows, helping to shed some light on its main operating channels under a rather simple Cournot’s duopolistic competition framework.

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This article proposes an alternative methodology for estimating the effects of non-tariff measures on trade flows, based on the recent literature on gravity models. A two-stage Heckman selection model is applied to the case of Brazilian exports, where the second stage gravity equation is theoretically grounded on the seminal Melitz model of heterogeneous firms. This extended gravity equation highlights the role played by zero trade flows as well as firm heterogeneity in explaining bilateral trade among countries, two factors usually omitted in traditional gravity specifications found in previous literature. Last, it also proposes a economic rationale for the effects of NTM on trade flows, helping to shed some light on its main operating channels under a rather simple Cournot’s duopolistic competition framework

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Alasdair Gray is now an established figure in the Scottish literary scene and has numerous claims to be considered an important voice writing in English. First Lanark: A Life in Four Books (1981) and then 1982 Janine (1984) contributed to the recognition of Gray as one of the founding fathers of the new Scottish writing and as a figure of importance in international contemporary fiction due to his innovative, experimental and postmodernist novels. As the title of this dissertation - “Alasdair Gray’s 1982 Janine (1984): A Postmodernist Scottish Novel” - suggests, it aims at analysing the author’s second novel, 1982 Janine (1984), in a thematic and formal perspective, in order to justify the choice of the terms - Postmodernist and Scottish - to classify this novel. 1982 Janine projects a world through Jock McLeish’s mind and is a powerful stream-of-consciousness narrative. Jock is an alcoholic who lives a personal crisis and, therefore, tries to escape from his depressing reality through sexual fantasies and political diatribes. During a single night in a Scottish hotel room, he drinks and dreams, and spends the whole night alone with his fantasies and fears, his memories and hopes. In Chapter 11, the most daring experimental section of the novel, Jock attempts to commit suicide by taking an overdose of tablets with alcohol but fails. Following this, he decides to review his life and make for a new beginning; the novel thus closing with an optimistic note. Also, the narrative is based on a constant interweaving of sex fantasy with political satire, that is, it is through his protagonist that Gray manages to convey the state of Scotland as well as the concerns and aspirations of the Scottish people and then, proceed to a political and social critique. This dissertation appears structured in three chapters. In Chapter I - “Alasdair Gray: A Postmodernist Scottish Writer” - I present Gray as a powerful postmodernist writer who also sees himself as a Scottish author, and more particularly as a Glaswegian, who concentrates on Scottish subject matter in his literary work. In a first section, I offer a brief survey of the Scottish literary scene from the fourteenth to the twentieth century, in order to understand Gray’s choice of setting and themes and to check his influence or indebtedness to previous Scottish authors. As 1982 Janine is also a good example of selfconscious experimental writing, in a second section, I present various seminal fictional works that introduced and developed experimentalism in British fiction, in order to evaluate the influence of modernist developments in form and technique on recent experimental writing. The third section consists of an introduction to Gray’s work for he is not only a novelist, but also an artist, a playwright, a poet, an activist and a scholar. Chapter II - “Postmodernist Features in 1982 Janine” - aims at listing and examining the postmodernist devices that the novel includes, in what content and form are concerned. On the one hand, the use of a developed type of the modernist stream of consciousness, the presence of a protagonist who feels entrapped in a specific system, the quest for freedom, the incoherence and fragmentation of time, the nonchronological order of the narrative, the blending of fantasy and “reality”, as well as the importance of the Scottish material are definitely current aspects within postmodernist literature that can be found in Gray’s novel. On the other hand, the handling of literary self-conscious devices, such as typographical experimentation, presence of metafiction and intertextuality, and inclusion of an Epilogue, are likewise among recurrent postmodernist features. As the title - “A Narratological Analysis of 1982 Janine” - evidences, Chapter III offers a description of the mechanics of the narrative and its functioning in order to better understand the narrative technique of postmodernist fiction. This study is based primarily on Gérard Genette’s theoretical framework and terminology, presented in Narrative Discourse: An Essay in Method, an analytical tool that allows me to provide a more objective and scientific analysis. Hence, I follow the Genettian division of narrative discourse in Time, Mood and Voice while examining the novel. Finally, I proceed to a description of the intertextual relationships 1982 Janine establishes with other texts.

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“A Narratological Analysis of D. M. Thomas’s The White Hotel (1981)” originated within a seminar on British Postmodernist Literature during the first Master’s Degree in “British and North-American Culture and Literature” (2001-04) at the Universidade da Madeira set up by the Department of English and German Studies. This dissertation seeks to present a narratological analysis of Thomas’s novel. The White Hotel stands as a paradigmatic example of the kind of literature that has dominated the British literary scene in the past three decades, commonly referred to as postmodernist fiction, owing to its formal craftsmanship (multiplicity of narrative voices and perspectives, mixing of differing genres and text types, inclusion of embedded narratives) alongside the handling of what are deemed as postmodernist topoi (the distinction between truth and lies, history and fantasy, fact and fiction, the questioning of the nature of aesthetic representation, the role the author and the reader hold in the narrative process, the instability of the linguistic sign, the notion of originality and the moral responsibility the author has towards his/her work), The narratological approach carried out in this research reveals that Thomas’s text constitutes an aesthetic endeavour to challenge the teleological drive that is inherent in any narrative, i. e., the inevitable progression towards a reassuring end. Hence, the subversion of narrative telling, which is a recurrent feature in Thomas’s remaining literary output, mirrors the contemporary distrust in totalising, hierarchised and allencompassing narratives. In its handling of historical events, namely of the Holocaust, The White Hotel invites us to reassess the most profound beliefs we were taught to take for granted: progress, reality and truth. In their place the novel proposes a more flexible conception of both the world and art, especially of literary fiction. In other terms, the world appears as a brutal chaotic place the subject is forced to adjust to. Accordingly, the literary work is deemed hybrid, fragmented and open. So as to put forth the above-mentioned issues, this research work is structured in three main chapters. The initial chapter – “What is Postmodernism?” – advances a scrutiny not only of the seminal but also of more recent studies on postmodernist literary criticism. Following this, in Chapter II – “Postmodernist British Fiction” – a brief overview of postmodernist British fiction is carried out, focusing on the fictional works that, in my opinion, are fundamental for the periodising of British postmodernism. In addition, I felt the need to include a section – “D. M. Thomas as a Postmodernist Novelist” – in which the author’s remaining literary output is briefly examined. Finally, Chapter III – “A Narratological Analysis of The White Hotel” – proposes a narratological analysis of the novel according to the particular Genettian analytical model. To conclude, my dissertation constitutes an approach to D. M. Thomas’s The White Hotel as a text whose very existence is substantiated in the foregrounding of the contingency of all discourses, meeting the postmodernist precepts of openness and subversion of any narrative that claims to be true, globalising and all-inclusive.

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The definition of the boundaries of the firms is subject that has occupied the organizational theorists long ago, being the seminal work of Coase (1937) indicated as the trigger for one theoretical evolution, with emphasis on governance structures, which led to a modern theory of incomplete contracts. The Transaction Cost Economics (TCE) and Agency Theory arise within this evolution, being widely used in studies related to the theme. Empirically, data envelopment analysis (DEA) has established itself as a suitable tool for analysis of efficiency. Although TCE argues that specific assets must be internalized, recent studies outside the mainstream of theory show that, often, firms may decide, for various reasons, hire them on the market. Researches on transaction costs face with the unavailability of information and methodological difficulties in measuring their critical variables. There`s still the need for further methodological deepening. The theoretical framework includes classic works of TCE and Agency Theory, but also more recent works, outside the mainstream of TCE, which warn about the existence of strategies in use of specific assets that aren`t necessarily aligned with the classical ideas of TCE. The Brazilian oil industry is the focus of this thesis, that aimed to evaluate the efficiency of contracts involving high specificity service outsourced by Petrobras. In order to this, we made the categorization of outsourced services in terms of specificity, as well the description of services with higher specificity. Then, we verified the existence of relationship between the specificity of services and a number of variables, being found divergent results than those that are preached by the mainstream of TCE. Then, we designed a DEA model to analyze the efficiency in the use of onshore drilling rigs, identified among the services of highest specificity. The next step was the application of the model to evaluate the performance of drilling rigs contracts. Finally, we verified the existence of relationship between the efficiency of contracts and a number of variables, being found, again, results not consistent with the theory mainstream. Regarding to analyze of efficiency of drilling rigs contracts, the model developed is compatible with what is found in academic productions in efficiency of drilling rigs. The results on efficiency show a wide range of scores, with efficiencies ranging from 31.79% to 100%, being low the sample efficiency average. There is consonance between the model results and the practices adopted by Petrobras. The results strengthen the DEA as an important tool in studies of efficiency with possibility to use for analysis other types of contracts. In terms of theoretical findings, the results reinforce the arguments that there are situations in which the strategies of the organizations, in terms of use of assets and services of high specificity, do not necessarily follow what is recommended by the mainstream of TCE

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This employment has the function the utilization of mango seeds Tommy Atkins, like starch source to obtain biopolymers and fibers source and nanowhiskers cellulose also, that will be use like reinforcing fillers in micro and nanobiocomposites polymeric. The fibers in natura removed from tegument mango seed were characterized, as weel as the treated fibers and nanowhiskers of cellulose extracted from them. The starch extracted from seed s almond showed a good performance (32%) and a high purity. The chemicals analyzes, of crystallinity and morphological of the fibers in natura, treated fibers and nanowhiskers of cellulose confirmed the efficacy of the chemical treatement performed to remove amorphous constituents (hemicellulose and lignina). The thermoplastic starch (TPS) obtained from two sources, corn starch and starchy material mango, was produced in a twin screw extruder with compositon mass of 62,5% of starch, 9,4% of water and 28,1% of glycerol. The starch material mango was the main objective of this work for the production of biodegradable materials, and the starch corn was utilized during the production stage to evaluate the processability of the starch and use as parameter for comparison, according of being a conventional source for obtaining conventional comercial starch. The incorporation of fibers (6% in mass) and nanowhiskers cellulose (1% in mass) in matrix of TPS to obtain composite and nanocomposite, respectively, it was performed in single screw extruder. The biocomposites and bionanocomposites polymeric were obtained and the TPS from starchy material mango presented better results of thermal and mechanicals properties when compared to TPS corn starch. Concludes that the sediment generated of the agroindustrial processing mango used presents potencial to producing of biodegradables materials

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Ucides cordatus is the most commercially, important mangrove crab in Brazil. In spite of its economic importance, there are few studies of its reproduction, in particular the female reproductive system. The present study describes the histology and histochemistry of the spermathecae of U. cordatus. Adult females were can lit monthly from July 2004 through June 2005, at Iguape, State of São Paulo. The crabs were anaesthetized, and their spermathecae removed and fixed in Davidson's fluid, following the histological routine for paraffin. The slides were stained with HE, xylidine Ponceau, PAS, alcian blue (pH 1.0 and 2.5), Sudan black B and picrosirius-haematoxylin. Histologically, the spermathecae possesses a capsule of conjunctive tissue, rich in collalgen fibres, which surrounds the secretory columnar epithelium. In the lumen, individual sperm packets are not observed; the spermatophores are intermixed with the seminal fluid and secretions of the spermathecae itself. A large proportion of the free spermatozoids and spermatophores are arranged in homogeneous masses in the proximal part of the spermathecae. The secretion produced by the columnar epithelium appears to promote the movement of the gametes to the fertilization chamber, in a ventral position, allowing fertilization of the oocytes. Histochemically, the secretion produced by the columnar epithelium was strongly positive for neutral polysaccharides, positive for acid polysaccharides, and weakly positive for proteins and lipids. Tills secretion forms a glycoprotein matrix which is associated with maintenance of the spermatophores, which can remain stored for long periods.

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Objetivou-se determinar a dose inseminante adequada para uso na fertilização artificial de ovócitos de dourado (Salminus brasiliensis). Os ovócitos foram distribuídos em delineamento inteiramente casualizado, e fertilizados com uma das relações espermatozoides/ovócito 6,0×10³; 6,0×10(4); 6,0×10(5); 6,0×10(6) ou 3,0×10(7), cada uma com quatro repetições. Considerou-se unidade experimental uma incubadora de volume útil de 2,5 L, contendo 2,0 mL de ovócitos não-hidratados. As taxas de fertilização foram mensuradas 8 horas após o início da fertilização. Com intuito de verificar possíveis efeitos da diluição seminal na movimentação dos espermatozoides, realizou-se a mensuração do tempo de duração da motilidade espermática dos espermatozoides de dourado, ativados por meio de diferentes relações de diluição: 6,8×10-5; 6,8×10-4; 6,8×10-3; 6,8×10-2; 3,4×10-1 e 1,0 mL de sêmen por mL de água. O tempo de duração da motilidade foi avaliado em delineamento inteiramente casualizado composto de seis tratamentos e três repetições. As taxas de fertilização apresentaram relação quadrática com o número de espermatozoides por ovócito. As relações de diluição do sêmen tiveram efeito inversamente proporcional sobre a duração da motilidade espermática. A relação que proporcionou melhores taxas de fertilização artificial de ovócitos de dourado (Salminus brasiliensis) foi de 30.722 espermatozoides por ovócio.

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Introdução: A obesidade e suas formas extremas como a forma mórbida, vem assumindo preocupação nos sistemas de saúde pública e é atualmente considerado um dos mais importantes agravos de saúde no mundo desenvolvido. Acarreta repercussões em várias partes do corpo, com potencial para interferir negativamente também na função reprodutiva, recentemente sendo mais estudado na população masculina. Objetivo: avaliar parâmetros hormonais e seminais da função reprodutiva em um grupo de homens obesos mórbidos, antes e após 6 meses da perda de peso induzida pela cirurgia bariátrica. Métodos: Inicialmente, de uma amostra de 36 pacientes com idade entre 18 e 40 anos e índice de massa corporal (IMC) ≥40 Kg/m2, apenas 1 caso foi excluído por ser portador de hiperprolactinoma e outros 24 pacientes não completaram todo o protocolo de avaliação laboratorial solicitada. Um total de apenas 11 pacientes completou o protocolo. Todos foram previamente avaliados por uma equipe multidisciplinar. O grupo selecionado foi submetido a avaliação seminal e dosagens hormonais de testosterona total(TT), FSH e LH. Os parâmetros foram reavaliados após 6 meses de realização da cirurgia pela técnica de Y-em-Roux, para análise dos efeitos da perda de peso sobre os parâmetros da função reprodutiva. Resultados: No grupo selecionado ao estudo, os exames pré-operatórios mostraram um grupo heterogêneo de resultados. Após seis meses do tratamento cirúrgico, a perda ponderal foi significativa no grupo analisado, com redução do IMC de mediana 46 Kg/m2para mediana de 36 Kg/m2(p=0,03). Em relação ao perfil hormonal, houve elevação significativa do nível sérico de TT com mediana de 187ng/ml no período pré-operatório para 457 ng/ml (p=0,02) no período pós-operatório. Entre os períodos pré e pós-operatório, não foram observadas alterações significantes do FSH (2,70 mIU/ml para 3,31 mIU/ml, p=0,79), LH (4,82 mIU/ml para 3,00mIU/ml, p=0,39), concentração espermática (38milhões/ml para 31milhões/ml, p=0,88) e motilidade A+B (50% para 50%, p=0,89).Conclusão: A redução ponderal decorrente da cirurgia em obesos mórbidos parece levar a uma elevação dos níveis de testosterona total, sem alterações nas demais provas de avaliação reprodutiva. Estudos adicionais com casuística maior e múltiplos parâmetros são necessários para esclarecimento definitivo do impacto da obesidade e da perda de peso induzida pela cirurgia sobre a função reprodutiva masculina

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A total of 58 Ucides cordatus (Linnaeus, 1763) ovigerous females in final embryonic stage were collected in mangrove forest at Iguape (São Paulo). Each female were kept in laboratory until the larvae hatching and had their carapace width (CW) measured with caliper (0.05 mm) and the larval number (LN) calculated by volumetric method. The hatching rates (HR) were calculated for each animal's size class (5 mm). The values of LN and CW obtained were subjected to regression analyses and the best fitting model was chosen by comparing the obtained determination coefficients (R²). The fertility varied from 71,200 to 220,800 larvae (147,169 ± 32,070 larvae), corresponding to 41.7 to 76.8 mm CW (63.7±7.9 mm), respectively. The relationship LNxCW was expressed by the equation LN = 284.1CW1.5º¹ (N = 58; R² = 0.74; p < 0.01), that showed a positive correlation between the variables. Most part of ovigerous females (89.7%) showed their hatching during the nightly period. A negative correlation between HR and CW was observed in these animals (p < 0.05), probably due to reduction of spermatophores in the seminal receptacle (multiparous females) or due to senility in the females with large size. The biological studies of U. cordatus are very important for practices adoption that preserve and make the rational use of this recourse in Brazilian's mangrove forests.