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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Uma ferramenta automatizada para gerenciamento da configuração de software

Koblitz, Leonardo Falcão, Instituto de Engenharia Nuclear 04 1900 (has links)
Submitted by Marcele Costal de Castro (costalcastro@gmail.com) on 2017-10-10T16:47:10Z No. of bitstreams: 1 LEONARDO FALCÃO KOBLITZ M.pdf: 2798440 bytes, checksum: e6bbe4d0c09a231a9612c35acb27e46b (MD5) / Made available in DSpace on 2017-10-10T16:47:10Z (GMT). No. of bitstreams: 1 LEONARDO FALCÃO KOBLITZ M.pdf: 2798440 bytes, checksum: e6bbe4d0c09a231a9612c35acb27e46b (MD5) Previous issue date: 1991-04 / Este trabalho apresenta o SAGCS, uma ferramenta automatizada para gerenciamento da configuração de software para ambientes DOS. Além de controlar o acesso aos arquivos sob seu controle, fornece vários relatórios, que permitem o usuário acompanhar precisamente a evolução do sistema. Em conjunto com esta ferramenta, são sugeridos um modelo e procedimentos para a elaboração e implantação de um plano de gerenciamento da configuração de software que melhor atenda as características de cada projeto de software.
2

Evolutionary history of clathrin-mediated endocytosis and the eisosome

Cibrario, Luigi January 2011 (has links)
Endocytosis is both an ancient and a diverse feature of the eukaryotic cell. Studying how it evolved can provide insight into the nature of the last common eukaryotic ancestor, and the diversification of eukaryotes into the known extant lineages. In this thesis, I present two studies on the evolution of endocytosis. In the first part of the thesis I report results from a large-scale, phylogenetic and comparative genomic study of clathrin-mediated endocytosis (CME). The CME pathway has been studied to a great level of detail in yeast to mammal model organisms. Several protein families have now been identified as part of the complex set of protein-protein and protein-lipid interactions which mediate endocytosis. To investigate how such complexity evolved, first, I defined the modular nature of the CME interactome (CME-I) by literature review, and then I carried out a systematic phylogenetic and protein domain architecture analysis of the proteins involved. These data were used to construct a model of the evolution of the CME-I network, and to map the expansion of the network's complexity to the eukaryotic tree of life. In the second part of the thesis, I present results from evolutionary and functional studies of the eisosome, a protein complex which has been proposed to regulate the spatial distribution of endocytosis in S. cerevisiae. The phylogeny of eisosomes components Pil1 and Lsp1 reported here, suggests that eisosomes are likely to have originated at the base of the fungi, and then diversified significantly via multiple gene duplications. I thus studied the localisation and function of Pil1 and Lsp1 homologues in Magnaporthe oryzae to investigate the role of eisosomes in filamentous fungi. Results suggests that eisosomes are linked with septal formation and integrity in M. oryzae, and that the septal specific Pil2 paralogue was lost in budding yeasts. Together, the data presented in this thesis describe the evolutionary history of a complex biological system, but also highlights the problem of asymmetry in the understanding of endocytic diversity in the eukaryotes.
3

Developmental architecture of human lymphopoiesis / Architecture développementale de la lymphopoïèse humaine

Alhaj Hussen, Kutaiba 20 September 2016 (has links)
Selon le modèle standard de l'hématopoïèse, la différenciation des cellules souches hématopoïétiques est un processus graduel de type arborescent. La première séparation a lieu au niveau de cellules multipotentes qui se scindent en progéniteurs lymphoïdes et myéloïdes communs. Bien que l'architecture de l'hématopoïèse humaine reste encore mal connue, de nombreux travaux suggèrent qu'elle ne suit pas le modèle standard. À ce jour encore, la question de l'existence d'un équivalent humain du CLP murin, n'a pas été tranchée. L'étude de l'hématopoïèse humaine soulève des problèmes méthodologiques. Ceci est lié au difficile accès au; prélèvements de moelle primaire et les études sur le sang placentaire ne reflètent pas complétement le développement médullaire. Dans ce travail, nous avons utilisé un modèle in vivo d'hématopoïèse foetale humaine chez la souris NSG par xénogreffe de progéniteurs du sang placentaire. La caractérisation faite sur les populations générées dans la moelle osseuse de souris a révélé que ce modèle reproduit l'hématopoïèse foetale humaine. Nous montrons que la lymphopoïèse foetale humaine présente une organisation originale caractérisée par une duplication des axes développementaux. Nos travaux mettent en évidence l'émergence indépendante de deux type de progéniteurs lymphoïdes à partir d'un intermédiaire multipotent: une population ancestrale CD127+générant principalement des lymphocytes B folliculaires, ainsi que des cellules ILC3 ; une population CD127- générant des lymphocytes T, des lymphocytes B de la zone marginale, et des cellules NK/ILC1. Ces résultats montrent que l'hématopoïèse humaine ne suit pas le modèle standard établi chez la souris. / The standard model of hematopoiesis proposes that hematopoietic differentiation is a stepwise bifurcation process. The first separation downstream of hematopoietic stem cells will segregate mutipotent progenitors into common lymphoid and myeloid progenitors. In human many evidences support the idea that human hematopoietic organization doesn't follow the classical model, but the question was not concluded and need for further investigation. Due to limited access to primary bone marrow samples and lack of appropriate in vivo model human studies face many difficulties. In this work, we used a xenogeneic model of human fetal hematopoiesis in immune-deficient mice to dissect the early stages of lymphoid development. This model relies on the injection of UCB CD34+ cells into NSG mice. Flow cytometry analysis and gene expression profiling of humanized mice BM populations revealed that this model faithfully reproduces human fetal hematopoiesis. Combining in vitro differentiation assays to molecular studies and genetic approaches, we show that fetal human lymphopoiesis displays a dual organization, split into an ancestral CD127+ CLP-like population devoid o myeloid potential that differentiate preferentially into follicular B cells and ILC3s, and into a previously undescribed CD127- population mainly dedicated to the generation of T, marginal zone B, NK, and ILC1s We also provide evidence that Early Lymphoid Progenitors emerge independently from multipotent developmental intermediates referred to as lympho-mono'dendritic progenitors. These results confirm that human hematopoiesis doesn't follow the standard model of hematopoietic differentiation established in the mouse.
4

Stroj času jako kulečník / Billiard time machine

Dolanský, Jindřich January 2011 (has links)
Title: Billiard time machine Author: Jindřich Dolanský Department: Institute of Theoretical Physics Supervisor: doc. RNDr. Jiří Langer, CSc. Supervisor's e-mail address: Jiri.Langer@mff.cuni.cz Abstract: In this work we investigate a simple interacting system of an elastic particle in the non-relativistic spacetime with a nontrivial causal structure realized by a worm- hole with a time shift. We require that standard local physical laws hold, and search for their globally consistent solutions, i.e, we assume the validity of the principle of self-consistency. If there were nontrivial set of initial conditions which would violate this principle, the system would be logically inconsistent. We show that the investigated system is not inconsistent in this sense, i.e., that all standard initial conditions have a globally consistent evolution. Even for the so called dangerous initial conditions which threaten to result into the paradoxical situation a consistent solution exists. In this case, the paradoxical collision-free trajectory is superseded by a special consistent self-colliding trajectory. Moreover, we demonstrate that more than one globally consistent evolution exists for a wide class of initial conditions. Thus, the evolution of the described system is not unique due to the nontrivial causal structure...
5

The evolution of social behaviour : the effect of mating system and social structure in the European badger Meles meles

Dugdale, Hannah L. January 2007 (has links)
Studies of mating systems and social organisation have been central to understanding of the evolution of social behaviour. The European badger Meles meles is a good species in which to study these processes, as its complex social system provides an opportunity to investigate how both natural and kin selection shape the evolution of mating systems and social structure. In this thesis, I use behavioural and genetic data to describe the mating system and social organisation of a high-density badger population and examine the occurrence of cooperative breeding. I genotyped 915 (85%) badgers trapped in Wytham Woods (1987–2005), 630 of which were cubs, and assigned both parents to 331 cubs with 95% confidence. This revealed a polygynandrous mating system, with up to five mothers and five fathers per social group. Mounting behaviour was also polygynandrous and I show the strongest evidence to date for multiple-paternity litters. I demonstrate, for the first time, that groups consisted of close and distant kin: approximately one third of group members were first-order kin, and overall group members had slightly lower relatedness levels than half-siblings. Within groups, adult and yearling females had higher pairwise relatedness than males, and neighbouring groups contained relatives. These findings result from the high level (42%) of extra-group paternities, 86% of which were assigned to neighbouring males. For the first time I show that females avoided inbreeding by mating with extra-group males; however, incestuous matings did occur. Promiscuous and repeated mountings were observed, which may reduce male–male aggression and infanticide, but may also promote sperm competition, genetic diversity, and / or genetic compatibility. Just under a third of adult males and females were assigned parentage each year and I quantify, for the first time, reproductive skew within badger groups. Correlations between relatedness, group productivity, and reproductive skew were not consistent with the predictions of incomplete-control models; rather, resource availability may play a role. Older and younger badgers displayed reduced annual breeding success, with male success increasing initially with experience. The Restraint, Constraint, and Selection Hypotheses did not explain the age-related breeding pattern in females. Variance in lifetime breeding success (LBS) was greater for males. Males that only bred within or only outside of their groups had half the LBS of males that did both. Females that were assigned maternity probably bred cooperatively and allonursed non-offspring, which has not been demonstrated previously. No benefit was established, however, in terms of litter size, probability of offspring breeding, or offspring lifetime breeding success, with more mothers in a group. In conclusion, badger social groups are fostered through kinship ties. Polygynandry and repeated mounting may have evolved originally to reduce male–male aggression and infanticide by males, through paternity masking. Although plural breeding occurs, group living appears to be costly. Motivation to disperse may be reduced through high-levels of extra-group paternities, which may also reduce inbreeding. Cooperative breeding among mothers may represent a low-cost behaviour with indirect benefits due to high levels of relatedness between female group-members. Badger sociality therefore represents an early stage in the evolution of social behaviour.

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