Made available in DSpace on 2016-04-27T19:30:31Z (GMT). No. of bitstreams: 1 Cristina Toledo de Carvalho.pdf: 630679 bytes, checksum: a815690ecb27d9bdb6d8d27efd773892 (MD5) Previous issue date: 2012-05-17 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This research analyses the performance of the Brasil Unido Beneficent Society, in the context of the correlation of strengths and historical conjunctures presented in São Caetano do Sul, between 1950 and 1965. Founded in 1950, by a group consisting most of socially and economically stable people from the Northeast part of Brazil, this society had as its main goal to give support to migrants from this part of the country. Such initiatives were concretized by mutualist and philanthropic ways. The mutualist initiatives were featured by practices such as monetary assistance to its members, in case of illness, financial issues and unemployment. The philanthropy was directed to not members and provided shelter, feeding, employment and health treatment. Craving the strengthening of the group, its directors embrace a strategy to enlarge the work, starting to benefit not only people from the Northeast. This way, the Brasil Unido would have more conditions to stand out among the acting forces in the city, giving its projects visibility and fundraising increase alternatives. The search for resources made its directors developed a relationship with the municipal, state and federal political system. Speachs to propagate the society work, guided and fortified by these relations, disseminated the group concept about the people benefited by its actions. This concept was close to the preconception presented in the social imaginary in those times, that conceived migrants as a violent, without culture and rough people. This preconception induced the Brasil Unido to propose an adaptation of those people to the habits and costumes of the city, seeking for their social inclusion in a scenario defined by an increasing urbanization and industrialization, such as São Caetano do Sul / A presente pesquisa analisa a atuação da Sociedade Beneficente Brasil Unido, no contexto da correlação de forças e das conjunturas históricas de São Caetano do Sul, no período compreendido entre 1950 e 1965. Fundada em 1950, por um grupo constituído predominantemente por nordestinos que possuíam certa projeção socioeconômica, a referida entidade tinha como finalidade precípua a promoção de iniciativas de amparo junto a migrantes provenientes do Nordeste. Tais iniciativas concretizavam-se a partir de duas vias: a mutualista e a filantrópica. Enquanto a primeira era caracterizada por práticas representadas, basicamente, pela concessão de auxílios monetários a sócios da instituição em casos de doença, dificuldades financeiras e desemprego, a segunda estava voltada para os não associados e consistia, principalmente, na disponibilização de abrigo, alimentação e providências para a obtenção de emprego, documentos e tratamentos médicos para os migrantes. Almejando o fortalecimento da entidade, a sua direção adotou a estratégia de expandir a política de amparo, que, assim, passou a beneficiar não somente nordestinos. Com uma proposta mais abrangente, a Brasil Unido teria maiores condições de se colocar, mais efetivamente, entre as forças atuantes no município sul-sancaetanense, o que poderia lhe render uma maior visibilidade e o aumento de suas possibilidades de arrecadação de recursos para os seus projetos e empreendimentos. A busca por recursos moveu, aliás, os seus dirigentes em suas articulações e relações com o sistema político da época, tanto em níveis municipal e estadual, quanto na esfera federal. Pautavam e legitimavam tais relações discursos que, ao divulgarem as propostas e trabalhos da entidade, veicularam a sua concepção acerca do migrante nordestino amparado por suas ações. Tal concepção estava em sintonia com as representações preconceituosas recorrentes no imaginário social daquele momento histórico, as quais concebiam o nordestino como um ser sem cultura, violento, rude e marcado pelo flagelo da seca. A existência desse preconceito motivou a Brasil Unido a propor, entre as beneficências previstas por seus estatutos, a adaptação do migrante aos usos e costumes da localidade, vislumbrando, assim, a sua inserção social em um cenário como o de São Caetano do Sul, marcado por uma crescente urbanização e industrialização

Les signaux d'avertissement que portent les proies toxiques (ou autrement défendues) offrent une opportunité unique de développer une vision intégrative de la diversification biologique. Ces signaux sont soumis à une forte sélection naturelle et sexuelle. D'une part, la stratégie d'échantillonnage utilisée par les prédateurs, caractérisée par l'apprentissage des signaux associés à la toxicité, protège les signaux en forte fréquence dans la communauté de proies. Cette sélection fréquence-dépendante positive favorise l'uniformité des phénotypes et la convergence de signaux entre espèces toxiques (mimétisme mutualiste dit "Müllerien") dans de nombreux taxons. D'autre part, les signaux d'avertissement sont utilisés comme critères de choix entre partenaires sexuels et sont donc soumis à de la sélection sexuelle avec des conséquences importantes pour l'émergence de l'isolement reproducteur et la spéciation. Paradoxalement, malgré une forte sélection naturelle favorisant la convergence, les signaux d'avertissement sont incroyablement diversifiés, à la fois au sein de la même espèce et entre espèces. Cette diversification morphologique est souvent associée à une importante diversification des espèces à l'échelle des clades. Dans cette thèse, j'apporte quelques explications à ce paradoxe et j'affine ainsi notre compréhension de l'effet de la sélection fréquence-dépendante positive et du mutualisme sur la diversification à l'échelle micro- et macro-évolutive. Premièrement, je montre que la stratégie d'échantillonnage des prédateurs peut favoriser la diversification des signaux d'avertissement malgré une sélection fréquence-dépendante positive. Deuxièmement, je dissèque les conditions permettant l'évolution d'un isolement reproducteur stable, nécessaire à la spéciation, dans certaines situations écologiques où les signaux mimétiques sont sous sélection naturelle et sexuelle. Troisièmement, je décris des effets indirect de la sélection fréquence-dépendante sur la diversification à l'échelle macro-évolutive par le biais de contraintes spatiales et de convergences écologiques secondaires. / The display of warning signals by unpalatable (or otherwise defended) prey provides a wonderful opportunity for establishing an integrative view of biological diversification. Warning signals are known to be under strong natural and sexual selection. On the one hand, the sampling strategy of predators, characterized by a learned avoidance of signals associated with unpalatability, generates natural selection in favour of warning signals in high frequency in the prey community. Such positive frequency-dependent selection favours phenotypic uniformity and causes unpalatable species to converge on common warning signals (mutualistic "Müllerian" mimicry), as seen in a large panel of taxa. On the other hand, warning signals are used as a phenotypic cue for mate choice, generating sexual selection with important consequences for reproductive isolation and speciation. Paradoxically, despite powerful selection favouring phenotypic convergence, warning signals are fantastically diverse, both within and between species, and this morphological diversification is often associated with extensive species diversification at the clade level. In this thesis, I tackle this apparent paradox from the ground up and I thereby refine our understanding of the role of positive frequency-dependent selection and mutualistic interactions for evolutionary diversification at micro- and macroevolutionary scales. First, I show that the predator sampling strategy can favour the emergence of diversity of warning signals despite positive frequency-dependent selection. Second, I dissect the conditions allowing the evolution of strong and stable reproductive isolation, necessary for speciation to occur, in a number of ecological situations where warning signals are under natural and sexual selection. Third, I highlight important indirect effects of frequency-dependent selection on diversification at macro-evolutionary scale via spatial constraints and by-product ecological convergence.

Frente ao intenso processo de fragmentação florestal sofrido no Brasil, este trabalho avaliou o efeito da fragmentação de Florestas Estacionais Semideciduais no Estado de São Paulo sobre a interação Ficus eximia e vespas (polinizadoras e não-polinizadoras). A abordagem foi realizada em duas escalas, (1) Na paisagem, com comparações entre os dados encontrados nas regiões de Teodoro Sampaio (menos fragmentada); Gália (intermediária) e Ribeirão Preto (mais fragmentada); e (2) Na escala local, considerando as características da paisagem no entorno das plantas amostradas. As questões investigadas foram: (a) Existe limitação de pólen em paisagens muito degradadas? (b) A estrutura da comunidade de vespas varia de acordo com o nível de fragmentação e distúrbio dos hábitats? (c) Possíveis limitações de pólen ou parasitismo por vespas não-polinizadoras comprometem os componentes primários de fecundidade das figueiras nas paisagens mais fragmentadas? Para responder tais questões, coletamos figos na fase interfloral (após a entrada da polinizadora e antes da maturação das sementes e prole) e figos em fase próxima à emergência das vespas. Os resultados mostraram que não houve indícios de limitação de vespas polinizadoras em nenhuma das paisagens estudadas. As comunidades apresentaram padrão aninhado, ou seja, a comunidade mais pobre em espécies Teodoro Sampaio representou uma subamostra das comunidades mais ricas Ribeirão Preto e Gália. A disponibilidade de vespas polinizadoras parece ser maior na paisagem mais fragmentada. As vespas parasitas inquilinas afetaram negativamente as produções de sementes e polinizadores em Ribeirão Preto; as vespas galhadoras também afetaram negativamente a produção de sementes em Gália e a produção de sementes e polinizadores em Teodoro Sampaio. No entanto, não foram detectadas, em geral, relações significativas entre as variáveis relacionadas ao potencial reprodutivo das figueiras e as características das paisagens estudadas. O presente estudo mostrou que o mutualismo Ficus-vespas de figo parece ser robusto às alterações da paisagem em escala subcontinental. O sistema reprodutivo alógamo das figueiras, com polinização biótica aprimorada pelo vento torna esse sistema biológico bastante insensível às modificações ambientais em pequena escala. / Brazilian forests, especially in the central and southeast regions, have been subject to intense habitat fragmentation. This study evaluated the fragmentation effects of semideciduous seasonal forests in São Paulo on the interaction between Ficus eximia and associated wasps (pollinating and non-pollinating). Our approach comprised two scales: (1) landscape scale, for which we compared data from the studied regions, namely Teodoro Sampaio (less fragmented), Gália (intermediate) and Ribeirão Preto (more fragmented) and (2) local scale, for which we considered the characteristics of the surrounding landscape of the sampled plant. The investigated issues were the following: (a) Is there pollen limitation in greatly degraded landscapes? (b) Does wasp community structure vary with fragmentation level and habitat disturbance? (c) Is it possible that limitations of pollen or parasitism by nonpollinating wasps compromise the primary fertility components of fig trees in the more fragmented landscape? To answer these questions, we collected figs at interfloral phase (after the pollinator had entered the fig and before offspring and seeds had completed their development) and figs close to wasp emergence phase. The results showed no evidence of pollination limitation in any studied landscape. The communities had a nested pattern, i.e., the species-poorest community Teodoro Sampaio is a subsample of the richer communities Ribeirão Preto and Gália. The availability of pollinating wasps appears to be greater in more fragmented landscapes. Inquiline fig wasps negatively affected seed and pollinator production in Ribeirão Preto; galler wasps also negatively affected seed production in Gália and seed and pollinator production in Teodoro Sampaio. However, significant relationships between variables related to fig reproductive potential and landscape characteristics were generally not detected. This study showed that Ficus-fig wasp mutualism appears to be resistant to landscape changes on a subcontinental scale. The reproductive system of fig biotic pollination enhanced by the wind makes this biological system rather insensitive to small-scale environmental changes.

Plant-based defence mutualisms involve aspects of plant morphology that influence the performance of plant parasites, their natural enemies and trophic interactions. Leaf domatia, small indentations on the underside of leaves, can be structurally complex, and are often inhabited by potentially beneficial mites and other arthropods. Plant morphological traits such as domatia that enhance mutualistic relationships may result in increased plant growth rates, and reproductive success. New Zealand supports ~60 plant species that have domatia, the most speciose genus being Coprosma. The aim of this thesis was to examine factors that affect the production of leaf domatia and their relationship with foliar mite assemblages. The three main objectives of this thesis are: First, to investigate the production of foliar domatia and their susceptibility to limited resources, particularly to carbon availability. Second, to test if domatia are inducible structures during leaf ontogeny in the presence of foliar mites and/or fungi. Finally, to explore the effect of domatia availability on foliar mite assemblages on leaves with and without resident mites. This thesis tested the stated objectives using C. lucida, C. ciliata, C. foetidissima and C. rotundifolia, with a combination of field investigations and controlled manipulative experiments. The cost of domatia production was investigated using two field surveys and two controlled experiments. Under natural conditions the relationship between leaf morphology and domatia were measured in situ and across an altitudinal gradient. The experimental manipulations used carbon and nutrient stress, induced by temperature, light and fertilizer application. The second objective was experimentally tested under field conditions by manipulating foliar mites and fungal densities on C. rotundifolia. The third objective was investigated by manipulating domatia availability on C. lucida shrubs across three different vegetation types. Under field conditions, the number of domatia per leaf was associated with leaf morphology in C. lucida and C. foetidissima, but not C. rotundifolia. Foliar carbon showed a positive, but weak association with domatia production in C. foetidissima and C. ciliata. Altitudinal induced-carbon stress on domatia production was ambiguous. Domatia production in C. foetidissima was positively associated to altitude in field survey (1), and negatively associated in the second survey, with no correlation found between carbon and altitude. Experimental C. rotundifolia shrubs held under elevated night-time temperatures showed a 2.5 fold increase in respiration, a 34% to 91% decrease in daily carbon gain, and 38% decrease in domatia per leaf mass. Domatia production showed no significant differences under nutrient stress. The results showed little evidence to support a role for induction of domatia. Domatia production in new leaves was similar across all experimental treatments. Diverse vegetation types supported 60% higher mite species. Leaves with domatia supported ~22 to 66% higher mite densities, greater colonisation success and more diverse mite assemblages, than those without domatia. In the pastoral vegetation, the absence of predatory mites on experimental shrubs resulted in no differences in fungivorous mite densities regardless of domatia availability. Plant investment in foliar domatia appears associated with the number of available sites on the leaf under field conditions. The role of carbon availability during leaf ontogeny suggests a complex and highly variable association with domatia production. Domatia are constitutive defence structures that influence mite assemblages, mediating both beneficial and antagonistic relationships. This thesis concludes that domatia are in part, carbon-based non-inducible structures that influence mite assemblages, plant-mite and mite-mite interactions, and increase the probability of successful colonisation.

Symbiosis is the close and protracted interaction between organisms. The molecular interactions that occur during symbiosis are complex with multiple barriers that must be overcome. Many Gram-negative, host-associated bacteria use a type III secretion system to mediate associations with their eukaryotic hosts. This secretion system is a specialized apparatus for the injection of type III effector proteins directly into host cells, which in the case of plant pathogens, are collectively necessary to modulate host defense. The type III secretion system is not a mechanism exclusive to pathogens, however, as many strains of commensal Pseudomonas fluorescens and mutualistic rhizobia demonstrably require a type III secretion system to interact with their host plants. The work presented in this thesis describes genome-enabled approaches for characterizing type III effector genes across the range of plant symbiosis. Using high-throughput sequencing technology, draft genome sequences were generated for the plant pathogen, Xanthomonas hortorum pv. carotae M081, the plant commensal, Pseudomonas fluorescens WH6, and six strains from the plant mutualists Sinorhizobium fredii and Bradyrhizobium japonicum. Analyses of the draft genome sequences and publicly available finished sequences contributed insights into mechanisms of host-association and to increasing the inventory of type III effector sequences as well as developing methods directly applicable for agriculture. Finally, characterization of the genetic diversity of type III effectors from rhizobia shows that collections of type III effectors of mutualists are static, with little diversity in content and sequence variation. This represents the first comprehensive cataloging of type III effector from species of mutualistic bacteria and the first to provide evidence for purifying selection of this important class of genes. / Graduation date: 2012

The primary objectives of this research were to demonstrate that: 1.) antibiotic resistant bacteria can promote the survival of antibiotic sensitive organisms when grown simultaneously as biofilms in antibiotics, 2.) community-level multiple antibiotic resistance of polymicrobial consortia can lead to biofilm formation despite the presence of multiple antibiotics, and 3.) biofilms may benefit plasmid retention and heterologous protein production in the absence of selective pressure. Quantitative analyses of confocal data showed that ampicillin resistant organisms supported populations of ampicillin sensitive organisms in steady state ampicillin concentrations 13 times greater than that which would inhibit sensitive cells inoculated alone. The rate of reaction of the resistance mechanism influenced the degree of protection. Spectinomycin resistant organisms did not support their sensitive counterparts, although flow cytometry indicated that GFP production by the sensitive strain was improved. When both organisms were grown in both antibiotics, larger numbers of substratum-attached pairs at 2 hours resulted in greater biofilm formation at 48 hours. For biofilms grown in both antibiotics, a benefit to spectinomycin resistant organism’s population size was detectable, but the only benefit to ampicillin resistant organisms was in terms of GFP production. Additionally, an initial attachment ratio of 5 spectinomycin resistant organisms to 1 ampicillin resistant organism resulted in optimal biofilm formation at 48 hours. Biofilms also enhanced the stability of high-copy number plasmids and heterologous protein production. In the absence of antibiotic selective pressure, plasmid DNA was not detected after 48 hours in chemostats, where the faster growth rate of plasmid-free cells contributed to the washout of plasmid retaining cells. The plasmid copy number per cell in biofilms grown without antibiotic selective pressure steadily increased over a six day period. Flow cytometric monitoring of bacteria grown in biofilms indicated that 95 percent of the population was producing GFP at 48 hours. This research supports the idea that ecological interactions between bacteria contribute to biofilm development in the presence of antibiotics, and demonstrates that community-level multiple antibiotic resistance is a factor in biofilm recalcitrance against antibiotics. Additionally, biofilms may provide an additional tool for stabilizing high copy number plasmids used for heterologous protein production.

The fungus-growing ants have long provided a spectacular example of co-evolutionary integration between distantly related taxa. Their ecological success has been thought to depend largely on the evolutionary alignment of reproductive interests between ants and fungi, following vertical transmission and the ancient suppression of fungal sexuality. In my dissertation I explored the role of lateral cultivar switching on the evolution of the fungus-gardening ant mutualism. First, I provided the first evidence for sexual reproduction in the attine cultivars, together with evidence of extensive independent long-distance horizontal transmission of fungal genes. In fact, fungi have greater gene flow relative to their host ants, crossing the Gulf of Mexico between Latin America and Cuba, over which the ants cannot readily disperse. Second, for the special case of leaf-cutting ants, I show that the cultivar population was largely unstructured with respect to host ant species, and leaf-cutting ants interact largely with a single species of fungus. Finally, I examined the effect of post-glacial expansion on the population structure of the northern fungus-gardening ant Trachymyrmex septentrionalis and compared it with that of its two microbial mutualists: a community of lepiotaceous fungal cultivars and associated antibiotic-producing Pseudonocardia bacteria. This comparison allowed me to examine the effect of historical biogeographic forces, such as climate-driven range shifts, on the population structure of the ants and their microbial symbionts. While neither the cultivar nor the Pseudonocardia genetic structure was correlated with that of the ants, they were significantly, though weakly, correlated with each other. These results suggest that biogeographic forces may act differently on macro- and microscopic organisms, even in the extreme case where some microbial mutualists may be vertically transmitted from generation to generation and share the same joint ecological niche. Thus, binding forces that appear to enforce host fidelity are relatively weak and pairwise associations between cultivar lineages and ant species have little opportunity for evolutionary persistence. Taken together, my studies suggest that mechanisms other than long-term pairwise interactions between ants and fungi (so-called partner fidelity feedback) govern the evolution of the mutualism over evolutionary time. / text

Thesis (Ph. D.)--St. Mary's University, San Antonio, Texas, 2007. / "December 2007." Includes bibliographical references (p. 120-132) and appendices.

The symbiosis between plants of the legume family and nitrogen-fixing rhizobia underpins global food security. Legume crops are a major source of protein in human diets, either directly or indirectly as feed for livestock. Application of inoculant rhizobial strains is common practice in many areas, as plant growth is often nitrogen limited and the symbiosis can significantly enhance yields. However, rhizobial strains and outcomes of the symbiosis vary widely. This variation has also been studied by evolutionary biologists interested in the stability of mutualisms. They proposed that plants may prevent establishing symbioses with ineffective strains (partner choice), or provide them with fewer resources (sanctioning). I studied both mechanisms, combining modelling and experimental approaches. Mathematical modelling was used to predict how plants should allocate resources to maximise growth rates, depending on rhizobial nitrogen provision and carbon requirements and on soil nitrogen conditions. The use of marked mutant strains – easily distinguishable and differing in a single rhizobial characteristic – overcame previous experimental difficulties. It was found that pea (Pisum sativum L.) plants are not able to exert partner choice, but do sanction in a more complex way than was previously established. In line with model predictions, resources were preferentially allocated to the single – best available – strain, so that resources allocated to an intermediate-fixing strain depended on whether or not a strain providing more nitrogen was available. Contrary to model predictions, there was no indication of discrimination based on rhizobial carbon requirements. The results cannot be explained by resource allocation in proportion to nitrogen received, and indicate systemic integration of information from different nodules. I formulate a hypothesis about the underlying plant regulatory mechanisms, and discuss implications of the results for selecting inoculant strains and enhancing yields in the field. Future work will rely on further integration of theoretical and applied methods and perspectives.

Nous en savons encore peu sur la manière dont les organisations gèrent la complexité de l’environnement dans lequel elles évoluent, et en particulier sur les moyens qu’elles mettent en œuvre pour rester « elles-mêmes » tout en répondant aux pressions, parfois contradictoires, qui s’exercent sur elles. Cette question apparaît particulièrement prégnante pour les organisations qui se revendiquent d’un modèle alternatif au modèle dominant issu du système capitaliste, et qui présentent un caractère hybride, c’est-à-dire qui poursuivent une mission sociale en exerçant une activité commerciale. Dans cette thèse, nous nous intéressons au cas d’une mutuelle d’assurance française, la Ma, et du dispositif de planification stratégique qu’elle a mis en place entre 2007 et 2009. Nous appuyant sur une étude qualitative aux niveaux macro, meso et micro et sur une approche « par l’outil », nos résultats nous permettent de mettre en évidence les dynamiques divergentes et les tensions qui traversent la Ma et qu’elle doit parvenir à concilier, à intégrer, si elle ne veut pas disparaître ou perdre de vue sa mission sociale. Nous montrons que cette conciliation repose à la fois sur la forme complexe du dispositif qu’elle met en œuvre, dont la principale caractéristique est de revendiquer un caractère participatif et démocratique ; et sur le travail des acteurs à l’intérieur de l’organisation, qui démontrent une capacité à se saisir des enjeux stratégiques qui se posent à la Ma et à s’impliquer dans les réponses à y apporter. Cette recherche entend contribuer à la littérature institutionnelle relative à la gestion de la complexité au niveau organisationnel et à la « maintenance » des organisations hybrides en particulier. Elle s’adresse également à la littérature sur la pratique de la stratégie, en se saisissant de la question du rôle de la planification stratégique dans l’« intégration » des tensions organisationnelles. Enfin, elle prétend éclairer sous un angle rarement employé et pourtant riche, celui de l’outil, la question de la démocratie et de la participation dans les organisations. / How organizations cope with institutional complexity remains largely unexplored. Little is known, in particular, on how organizations manage to preserve their identity while responding to the often- conflicting demands of their environment. This issue is even more salient within hybrid organizations, ie. organizations which pursue a social mission through commercial activities, because they have to deal with intrinsic tensions between divergent logics. This dissertation focuses on the case of a French mutual insurance company, the Ma, and on the process of strategic planning it has implemented from 2007 to 2009 to elaborate its orientations. Based on an ethnographic observation of this process and a qualitative analysis at the macro, meso and micro levels, my results show that the Ma is indeed a hybrid and that to evolve and avoid mission drift, it had to overcome its internal tensions and integrate divergent dynamics of “maintenance” and “compliance”. The dissertation further explores the role played by the strategic planning process in this integration. In this case, it was achieved through both the complex shape of the apparatus of strategic planning, which main features were participation and democracy; and the work of internal actors, who demonstrated an ability to seize the strategic issues facing the Ma and to get involved in the drafting of relevant responses. This research aims to contribute to the institutional literature on the organizational responses to institutional complexity and to the "maintenance" of hybrid organizations in particular. It also addresses the literature on the practice of strategy by referring to the role of strategic planning in the integration of organizational tensions. Finally, it sheds light on the issue of democracy and participation in organizations through a tools-based approach, which is rarely used yet highly instructive.