859 resultados para melhoramento genético


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With: O novo argonauta / por José Agostinho de Macedo. Lisboa : Na typografia de Bulhões, 1825. -- Elogio historico do illustrissimo e excellentissimo Ricardo Raymundo Nogueira, conselheiro d'estado / por José Agostinho de Macedo. Lisboa : Impressão Regia, 1827. -- Refutação do monstruoso e revolucionario escripto impresso em Londres, intitulado, Quem he o legitimo rei de Portugal? / José Agostinho de Macedo. Lisboa : Impressão Regia, 1828.

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The objective of the present thesis was to use the manipulation of oocytes enclosed in preantral follicles (MOEPF) as a tool for the female gametes rescue and optimization, from wild species of Caatinga biome. The thesis was divided into 4 experiments. At first experiment, it was performed the estimative and description of the agouti (Dasyprocta leporina) preantral follicles (PF) histologic and ultrastructural features, in which it was estimated 4419.8 ± 532.26 and 5397.52 ± 574.91 follicles for the right and left ovary, respectively, and the majority (86,63%) belonged to the primordial follicles category (P<0.05). Most of the population consists of morphologically normal follicles (70.78%), presenting a large and central nuclei and uniform cytoplasm. At ultrastructural evaluation it was verified the presence of a great number of round mitochondrias associated to lipid droplets. In the second experiment, it was performed the estimative and description of yellow-toothed cavies (Galea spixii) PF characteristics, also, the evaluation of the effect of solid surface vitrification (SSV) on the in situ PF morphology. The total of 416.0 ± 342.8 PF was estimated for the ovary pair and the presence of a large quantity of primary follicles (P<0.05) was evidenced. Most of the PF was morphologically normal (94.6%), in which the oocyte nuclei presented condensed granules of heterochromatin. Round or elongated shaped mitochondria constituted the most abundant organelles. In regard of the SSV, the protocol using the dimethylsulfoxide (DMSO) 3M possibility the preservation of 69.5% of morphologically normal PF, which was evidenced by the light and transmission electronic microscopy. At third experiment, the evaluation of the SSV procedure on the morphology and viability in situ PF form collared peccaries (Pecari tajacu) was performed. No differences were observed among treatments, in which the use of DMSO, ethylene glycol (EG) and dimethylformamide (DMF) as cryoprotectants, regardless its concentration, promoted the morphology preservation of much than 70% of PF. Concerning the PF viability, the DMSO and EG promoted the best preservation. The fourth experiment aimed to evaluate the effect of α MEM+ or TCM199 associated or not to 50 ng of FSHr on the morphology, activation and growth of collared peccaries PF, in vitro cultured (IVC) during 1 or 7 days and the effect on the extracellular matrix (ECM). After 7 days of IVC only the use of TCM199/FSH maintained the proportion of intact PF, similar to day 1(63.2%), however, no differences were observed among treatments (P>0.05). Also, an improvement of the proportion of intact growing PF was verified (P>0.05). By the Ag-NOR analysis it was observed that only the treatment using TCM199/FSH promoted the maintenance of cell proliferation similar to day 1 (P>0.05). The picrosirius red stain revealed that ECM remained intact in all treatments (P>0.05). Thus, as the general conclusion, the use of MOEPF in the refereed species allowed the knowledge of aspects related to its reproductive morphology and physiology, enabling the germplasm conservation, with the possibility of germplasm bank formation, as the elucidation of mechanisms related to the PF survive and in vitro development.

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Through the nineteenth century, it was constant in the discourse of the local norte-rio-grandenses (Natal city, Brazil) administrators, the appeal for subsidy to the central government for the works of the port of Natal upgrade. The port in the capital, the main route of the Rio Grande do Norte communication, because of the limitations attached to it, as the dunes surrounding the city spreading sand in the riverbed, and several reefs located along the coast, did not allow the entry in his berth larger ships. These difficulties brought major problems the province, who could not hold the flow of production coming from the inside, resulting in the north of Rio Grande political scene, questioning the centrality of Christmas position in the province. Only Republican scheme had been approved credit by the federal government for the improvement works of the port. The port became the Republican political discourse Potiguar one of the main promises to bring "progress" the Potiguar land, being placed as a central issue of which depend on the "future" of the state. The objective of this study is to analyse the emergence of a new port concept in speeches and interventions of the local ruling groups in the early twentieth century. We analyse the emergence of a modern notion of port, marked by the organizing effort, rationalization and regulation of port activities by the state, and the new relationship assumed by the harbour front to the city resulting from this new perception. The port has become for local leaders to groups of capital "waiting room", requiring change of the composition of urban space for integrating the port to the city. The Port of Natal became endowed with a pedagogical function, incorporating the urban fabric, codes, values and practices considered by local managers as modern and civilized. This new city space, considered a "waiting room", caused conflicts between the local ruling groups and influential figures in the Potiguar political field, which sought to encourage with the process of organizing the harbour front undesirable regarded figures in the city views as an impediment to the image of progress and modernity that the dominant groups intended to expose the port.

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This work proposes a new autonomous navigation strategy assisted by genetic algorithm with dynamic planning for terrestrial mobile robots, called DPNA-GA (Dynamic Planning Navigation Algorithm optimized with Genetic Algorithm). The strategy was applied in environments - both static and dynamic - in which the location and shape of the obstacles is not known in advance. In each shift event, a control algorithm minimizes the distance between the robot and the object and maximizes the distance from the obstacles, rescheduling the route. Using a spatial location sensor and a set of distance sensors, the proposed navigation strategy is able to dynamically plan optimal collision-free paths. Simulations performed in different environments demonstrated that the technique provides a high degree of flexibility and robustness. For this, there were applied several variations of genetic parameters such as: crossing rate, population size, among others. Finally, the simulation results successfully demonstrate the effectiveness and robustness of DPNA-GA technique, validating it for real applications in terrestrial mobile robots.

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This work proposes a new autonomous navigation strategy assisted by genetic algorithm with dynamic planning for terrestrial mobile robots, called DPNA-GA (Dynamic Planning Navigation Algorithm optimized with Genetic Algorithm). The strategy was applied in environments - both static and dynamic - in which the location and shape of the obstacles is not known in advance. In each shift event, a control algorithm minimizes the distance between the robot and the object and maximizes the distance from the obstacles, rescheduling the route. Using a spatial location sensor and a set of distance sensors, the proposed navigation strategy is able to dynamically plan optimal collision-free paths. Simulations performed in different environments demonstrated that the technique provides a high degree of flexibility and robustness. For this, there were applied several variations of genetic parameters such as: crossing rate, population size, among others. Finally, the simulation results successfully demonstrate the effectiveness and robustness of DPNA-GA technique, validating it for real applications in terrestrial mobile robots.

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The HLA system is the most polymorphic genetic system described in humans. It consists of several closely linked loci encoding cell surface glycoproteins whose best known function is activating immune system response through antigenic presentation. New loci and new alleles have been described since the discovery of this genetic system and the presently available DNA typing and sequencing of these new alleles have increased the variety of HLA allelism. Due to the fact that HLA gene frequencies have a large degree of variability and a remarkable geographical correlation, HLA genes are an important and useful tool to infer genetic background and ethnical composition of modern human populations and also for tracing migration of ancient ones. In addition, certain combinations of contiguous alleles due to the strong linkage disequilibrium between HLA neighbouring loci show a characteristic frequency or are distinctive in many present day populations. Thus, HLA genetic system is a unique tool for studying the origin of relatively isolated groups, like Turkmen, Azeri and Kurd people, the populations under study, living in North Iran, in the surrounding area of Caspian Sea. Finally, HLA polymorphism is crucial for the compatibility between donor and receptor in organ transplantation and several HLA alleles have been linked to diseases and to response to drug treatments, which accomplishes relationships of certain variants with different pathologies treatment including AIDS. This is important in personalized treatments design. Turkmen could be descendants of Oghuz tribes from Seljuq branch coming from Transoxiana region (Central Asia) contemporarily to the foundation of the Seljuk Empire in 10th century AD. Conversely, this people could belong to another group within the Oghuz, arriving to Iran five centuries later. Migrations of this people were initially developed peacefully, being vassals of the Safavid Empire, and later by violent raids. They speak a language belonging to the Turkish-Oghuz group. In Iran, Turkmen live in Golestan province, mainly in Türkmensähra (“Turkmen plain”) area and amount 1.5 million people (2% of Iranian population). Most of this people are Sunni Muslims...

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El impacto que tienen los defectos congénitos sobre la salud de las personas afectadas, sus familias y sobre la sociedad en su conjunto es muy considerable. En España se estima que existe una prevalencia de anomalías cromosómicas hasta 2010 de 1,49% de los recién nacidos vivos. El Síndrome de Down (SD) es la tercera causa de defecto congénito y la primera de cromosomopatía, con una prevalencia de 23 por cada 10000 nacidos vivos. La importante morbilidad asociada en los individuos con síndrome de Down se acompaña de un alto coste económico, estimándose en 329750,63 euros por cada nuevo caso, constituyendo un cargo a lo largo de la vida de 1316 millones de euros. Por todo ello, la detección de esta alteración es la indicación más frecuente de diagnóstico prenatal invasivo. Las pruebas invasivas, como amniocentesis, biopsia de vellosidades coriales y cordocentesis, se asocian con un aumento del 1% del riesgo de aborto y, por tanto, sólo se realizan cuando se considera que hay una probabilidad elevada de que el feto tenga un defecto cromosómico, siendo por tanto fundamental una buena selección del grupo de gestantes de alto riesgo...

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[EN] Los análisis genéticos de las estrategias reproductivas (paternidad múltiple y almacenamiento de esperma) están abriendo una vía de investigación novedosa además de promover informaciones importantes para definir los criterios y las medidas de conservación de muchas especies de reptiles. La población de tortuga común, Caretta caretta del Archipiélago de Cabo Verde es una de las poblaciones nidificantes más grandes del Atlántico, pero que actualmente sufre la pesca selectiva de machos por parte de la comunidad local de Cabo Verde. En este estudio se pretende testar la hipótesis de que una disminución significativa en el número de machos podría afectar la eficacia biológica de las crías, disminuyendo la variabilidad genética de la población.

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Este trabalho apresenta um estudo de caso das heurísticas Simulated Annealing e Algoritmo Genético para um problema de grande relevância encontrado no sistema portuário, o Problema de Alocação em Berços. Esse problema aborda a programação e a alocação de navios às áreas de atracação ao longo de um cais. A modelagem utilizada nesta pesquisa é apresentada por Mauri (2008) [28] que trata do problema como uma Problema de Roteamento de Veículos com Múltiplas Garagens e sem Janelas de Tempo. Foi desenvolvido um ambiente apropriado para testes de simulação, onde o cenário de análise foi constituido a partir de situações reais encontradas na programação de navios de um terminal de contêineres. Os testes computacionais realizados mostram a performance das heurísticas em relação a função objetivo e o tempo computacional, a m de avaliar qual das técnicas apresenta melhores resultados.