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Orientador: Edilberto Giannotti / Banca: Fabio Prezoto / Banca: Maria Santina de Castro Morini / Banca: Odair Correa Bueno / Banca: Claudio José Von Zuben / Resumo: Ectatomma opaciventre (Hymenoptera: Formicidae: Ectatomminae) apresenta características morfológicas e comportamentais plesiomórficas, como a presença de um ferrão funcional, monoginia, colônias pequenas e estratégia de forrageamento solitário. Vive tanto nos ambientes preservados quanto nos alterados pelo homem, como os agroecossistemas, estando constantemente em contato com os produtos destinados ao controle de formigas consideradas pragas, como as cortadeiras do gênero Atta. Pouco se conhece a respeito de sua biologia básica (como dieta, rotas de forrageamento, distribuição espacial dos ninhos, composição dos hidrocarbonetos cuticulares) e das conseqüências advindas de seu contato com as iscas formicidas usadas para o controle de formigas cortadeiras em pastagens. Dessa forma, foi determinado por meio do "Método do Vizinho Mais Próximo" o padrão de distribuição espacial de seus ninhos em uma área degradada de 1800m2 na cidade de Rio Claro/SP/Brasil. Como na maioria das espécies de formigas tropicais, os ninhos de E. opaciventre apresentaram distribuição espacial do tipo regular ou hiperdispersa, com densidade de 0,018 ninho/m2. A distância média encontrada para o vizinho mais próximo foi de 5,57m, variando de 1,93m a 12,96m. Em vista da dificuldade em encontrar a rainha desta espécie, foi utilizado o método da "Espectroscopia Fotoacústica no Infravermelho com Transformada de Fourier (FTIR)" para identificar os hidrocarbonetos cuticulares da única rainha encontrada e das operárias de 9 ninhos satélites. Também foi determinado o grau de similaridade entre elas. Com os resultados obtidos ficou evidenciada a condição polidômica nessa espécie devido à semelhança entre o perfil químico cuticular da rainha e das operárias de ninhos vizinhos. Além disso... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Ectatomma opaciventre belongs to the subfamily Ectatomminae, which presents morphological and behavioral characteristics typical of more basal groups, such as the presence of a functional sting, monogyny, small colonies, and individual foraging strategies while searching for food. This species lives both in preserved and modified environments, such as agroecosystems, and it is constantly in contact with products intended to control ants regarded as pests, such as leaf-cutting ants of the genus Atta. The patterns of spatial distribution of nests over a 1800m2 degraded area in the city of Rio Claro, SP, Brazil were determined using a nearest neighbor method. As in most tropical species, the nests of E. opaciventre presented a regular or hyperdispersed spatial distribution, with a density of 0.018 nests/m2. The average nearest neighbor distance was 5.57 m, ranging from 1.93 m to 12.96 m. Considering the difficulty in finding queens of this species, the Fourier Transform-Infrared Photoacoustic Spectroscopy (FTIR-PAS) was used to identify cuticular hydrocarbons of the only queen found and of workers from nine satellite nests. The degree of similarity between them was also determined. From the results, polydomy was evident in this species because of the similarity between the cuticular chemical profile of the queen and that of workers from neighboring nests. Moreover, it was observed that the colonies that were not collected disappeared one year after the removal of the queen from the study area. In another area in the city of Rio Claro, of 4,800 m2, the diet of this species was studied by identifying the prey collected during the period of highest foraging activity. Besides, the foraging routes of three nests were determined by following foragers during their excursions in the field. The maximum foraging distance was... (Complete abstract click electronic access below) / Doutor

Made available in DSpace on 2014-06-11T19:22:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-04-29Bitstream added on 2014-06-13T19:49:26Z : No. of bitstreams: 1 souza_rf_me_rcla.pdf: 986867 bytes, checksum: 7df8039bc4e9ac93936dfae1fd472b5f (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / As formigas da espécie Solenopsis invicta são nativas da América do Sul, mas elas foram introduzidas em novos ambientes e passaram a causar sérios danos à agricultura e pecuária bem como causar alguns transtornos ao ser humano. Muitos estudos sobre a biologia reprodutiva de S. invicta foram conduzidos com populações introduzidas; porém, poucos com as populações nativas. As ferramentas moleculares como microssatélties e mtDNA podem auxiliar na investigação sobre a biologia reprodutiva das espécies. Diferentes comportamentos sociais de S. invicta como a monoginia e a poliginia, podem interferir na biologia reprodutiva da espécie, e a utilização das ferramentas moleculares corretas pode evidenciar este comportamento. A expansão das populações nativas, assim como a introdução dessa formiga em outros ambientes, pode ter levado à interação com outros táxons de formigas e com outros tipos de organismos. Essa interação pode ter sido responsável pela aquisição da endobactéria Wolbachia. Ela é uma bactéria intracelular que pode causar distúrbios reprodutivos em seus hospedeiros. Este trabalho analisou 10 ninhos de S. invicta coletados em cinco cidades do Estado de São Paulo com o objetivo de inferir sobre a biologia reprodutiva de S. invicta, utilizando marcadores moleculares microssatélites e mtDNA e também verificar a presença de Wolbachia. A formação de quatro grupos filogeneticamente distintos para mtDNA sugerem linhagens divergentes de haplótipos dentro dos dez ninhos. Essa separação também pode indicar interferências na dispersão natural das fêmeas. A análise dos microssatélites revelou que alguns problemas moleculares podem interferir na investigação sobre a biologia reprodutiva. A análise específica de poliginia indica que todos os ninhos analisados são monogínicos, mas os resultados de microssatélites sugerem que ninhos de S. invicta... / The ants of Solenopsis invicta are native of South America, but they were introduced into new environments and began to cause serious damage to agriculture and livestock and cause some inconvenience to humans. Many studies on the reproductive biology of S. invicta were conducted with introduced populations, but few with the native populations. The molecular tools such as analysis of mtDNA and microsatellites can assist in research on the reproductive biology of the species.Different social behavior of S. invicta as monogyny and polygyny, can interfere in the reproductive biology of the species, and the use of the correct molecular tools may show this behavior.The expansion of the native populations, as well as the introduction of this ant in other environments may have led to the interaction with other taxa of ants and other types of organism. This interaction may have been responsible for the acquisition of endobacteria Wolbachia. This bacteria is intracellular and can cause reproductive disorders in their hosts. This study analyzed 10 nests of S. invicta collected in five cities of São Paulo aiming to infer the reproductive biology of S. invicta, using microsatellite markers and mtDNA and also verify the presence of Wolbachia. The formation of four groups phylogenetically distinct mtDNA suggests divergent lineages of haplotypes inside the ten nests. This separation can also indicate interference with the natural dispersal of females. Analysis of microsatellite revealed that some molecular problems may interfere in the research on the reproductive biology. The specific analysis of polygyny indicates that all nests that were analyzed are monogynous, but results of microsatellite suggest that nests of S. invicta have more than one reproductive queen. The Wolbachia presence analysis revealed two strains, the A from subgroup InvA of the S. invicta and the B strain characteristic of ... (Complete abstract click electronic access below)

Orientador: Flávio Henrique Caetano / Banca: Mary Anne Heidi Dolder / Banca: Vera Nisaka Solferini / Banca: Fernando José Zara / Banca: Daniela de Oliveira Pinheiro / Resumo: Foram realizados estudos comparados do proventrículo, ventrículo, íleo e túbulos de Malpighi de três espécies pertencentes ao gênero Cephalotes: C. atratus, C. pusillus e C. clypeatus, objetivando buscar relações entre elas, assim como, diferenças histoquímicas e ultra-estruturais tanto da parede como do conteúdo destas porções do trato digestivo, que pudessem ser utilizadas para a melhor compreensão da função intestinal, bem como esclarecer quais e como os recursos alimentares são aproveitados em cada parte do trato digestivo. As características ultra-estruturais do ventrículo de Cephalotes atratus, C. clypeatus e C. pusillus, mostram que o epitélio do ventrículo repousa sobre uma lâmina basal contínua e é formado basicamente por três tipos celulares, sendo estas as células digestivas, as células regenerativas e as goblet cells. Nestas formigas, o retículo endoplasmático rugoso além de atuar na produção de enzimas digestivas também está envolvido na estocagem de íons em vacúolos especializados presentes no ventrículo. Estas concreções são os esferocristais e podem estar contribuindo com a estabilização do pH e permanência das bactérias simbiontes presentes por entre as microvilosidades. Secções realizadas ao longo do íleo revelaram diferenças entre três principais regiões: proximal, mediana e distal. As especializações estruturais presentes no íleo destas três espécies de formigas resultam em implicações especialmente relacionadas com as bactérias simbiontes aí hospedadas. Também foram realizados testes para verificar a diversidade da microbiota intestinal das porções em questão, usando a técnica DGGE. Assim sendo, o perfil molecular dos simbiontes do ventrículo e íleo de Cephalotes atratus, C. clypeatus e C. pusillus foi obtido analisando a região variável V3 do gene 16S do rDNA bacteriano... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This study compared the proventriculus midgut, ileum, and Malpighian tubules of three ants of the genus Cephalotes: C. atratus, C. pusillus, and C. clypeatus, by examining histochemical and ultrastructural differences in the wall and the content of these portions that could be used to better understand the intestinal function, as well as clarify which and how food resources are used in each part of the digestive tract. The ultrastructural analysis of the midgut of Cephalotes atratus, C. clypeatus, and C. pusillus reveled that the epithelium of the midgut lays on a basal lamina and is composed basically of three cell types: digestive cells, generative cells, and goblet cells. In these ants, the rough endoplasmic reticulum, in addition to producing digestive enzymes, is involved in ion storage in specialized vacuoles present in the midgut. These concretions are spherocrystals and may contribute to stabilize the pH and to maintain symbiotic bacteria found in between microvilli. Sections along the ileum revealed differences among the three main regions: proximal, medial, and distal. The structural specializations present in the ileum of these three ants have implications especially to the symbiotic bacteria. The DGGE method was also performed to assess the diversity of the intestinal microbiota of the portions of the digestive tract. The molecular profile of the symbionts of the midgut and ileum of Cephalotes atratus, C. clypeatus, and C. pusillus was obtained using the variable region V3 of the bacterial 16S rDNA gene sequence. Two samples of C. atratus, three of C. clypeatus, and six of C. pusillus were analyzed. The results showed similarity indices from 80% to 94% between the samples of symbionts from C. atratus and C. clypeatus, despite being collected in sites geographically distant. The variability of symbionts found in the samples of C. pusillus ranged from 45%... (Complete abstract click electronic access below) / Doutor

Orientador: Odair Correa Bueno / Banca: Luiz Carlos Forti / Banca: Maria Santina de Castro Morini / Banca: Osmar Malaspina / Banca: Ana Eugênia de Carvalho Campos Farinha / Abstract: The present work aimed to evaluate the efficiency of crude oils of Carapa guianensis Aubl. (crabwood), Elaeis guineensis Jacq. (African oil palm), Sesamum indicum L. (sesame), Ricinus communis L. (castor beans), Azadirachta indica Juss (neem), Theobroma cacao L. (cocoa), Anacardium occidentale L. (cashew nut) and crude extracts of Anacardium occidentale on leafcutting ants control, using Atta sexdens rubropilosa as model. Toxicity bioassays with ant workers were done using: 1) treatments by incorporation of crude oils or extracts in artificial diet and 2) treatments by topic application of crude oils or extracts on the ants pronotum. According to obtained results in toxicity tests, some crude oils and extracts were select to be incorporated in baits or applied by nebulization and tested on laboratory colonies. The crude oils or extracts more efficient on laboratory colonies control were tested on field grown up colonies. The obtained results in all toxicity tests permitted to select crude oils of C. guianensis, E. guineensis, S. indicum, R. communis, A. indica, A. occidentale and hexane, dichloromethane, ethyl acetate and methanol extracts of A. occidentale to be applied by nebulization and crude oils of E. guineensis, A. indica and A. occidentale to be incorporated in baits and tested on laboratory colonies. On laboratory colonies, the nebulization with crude oils of C. guianensis, E. guineensis, S. indicum, R. communis and A. indica didn't cause any effect on colonies. Therefore, these crude oils don't must be used to leaf-cutting ants control. However, crude oil and hexane, dichloromethane, ethyl acetate and methanol extracts of A. occidentale propitiated the extinction of colonies. The E. guineensis, A. indica and A. occidentale baits didn't any cause effect on colonies hence it follows that these baits don't must be used to leaf-cutting ant's control / Doutor

Orientador: Odair Correa Bueno / Banca: Luiz Carlos Forti / Banca: Ana Paula Protti de Andrade Crusciol / Banca: Maria Santina de Castro Morini / Banca: Sulene Noriko Shima / Resumo: O presente trabalho teve como objetivo o estudo da evolução dos comportamentos de preparação do substrato, cuidado com a cria e cuidado com a rainha e alados em formigas cultivadoras de fungo. Estas formigas pertencem à tribo Attini, subfamília Myrmicinae, e ocorrem exclusivamente no continente americano. Esta tribo contém aproximadamente 230 espécies, porém pouco se conhece da biologia da maioria delas, graças ao fato de serem extremamente crípticas e de não apresentarem importância econômica, como as formigas cortadeiras, que são as mais estudadas. Foram utilizadas seis espécies, que representam bem os diversos níveis da filogenia da tribo: Acromyrmex disciger, Apterostigma pilosum, Mycetarotes parallelus, Myrmicocrypta sp., Trachymyrmex fuscus e Trachymyrmex sp. nov. Os comportamentos foram estudados em ninhos mantidos em laboratório, com o auxílio de micro-câmeras e um aparelho gravador de vídeo. Os comportamentos foram analisados, caracterizados e quantificados. Os resultados foram divididos em três capítulos de acordo com o tipo de comportamento. No capítulo sobre a evolução dos comportamentos de preparação do substrato foi observado que, basicamente, o processo evoluiu no sentido de aumentar a capacidade das operárias em decompor inicialmente o substrato. As espécies basais, A. pilosum, M. parallelus e Myrmicocrypta sp. apresentaram um processamento mais simples com um número menor de comportamentos e principalmente sem os comportamentos do tratamento químico, que é responsável pela fragmentação do substrato ao mesmo tempo em que ele é tratado com enzimas digestivas. As duas espécies do gênero Trachymyrmex apresentaram um processo mais complexo com grande participação do tratamento químico. Em A. disciger, que é uma cortadeira, há uma intensa especialização do sistema de castas para o aumento da eficiência... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This work aims to study the evolution of the behaviors of substrate preparation, brood, queen and winged forms care in fungus growing ants. These ants are included in the tribe Attini, subfamily Myrmicinae, and occur exclusively in the american continent. This tribe contains approximately 230 species, but little is known about the biology of most of them, tanks to the fact that they show very cryptic habits and are not economically important, like the leaf cutting ants, which are the most studied. Six species were used in this work, which represent well all the levels of the phylogeny of the tribe: Acromyrmex disciger, Apterostigma pilosum, Mycetarotes parallelus, Myrmicocrypta sp., Trachymyrmex fuscus and Trachymyrmex sp. Nov. The behaviors were studied in laboratory nests, with a set of micro cameras and a video recording device. The behaviors were analyzed, characterized and quantified. The results were summarized and discussed in tree chapters, arranged by type of behavior. In the chapter about the evolution of the substrate preparation behaviors, basically it is assumed that this process evolved in order to develop the capacity of previously decompose the substrate by the workers. In the basal species, A. pilosum, M. parallelus and Myrmicocrypta sp. this process is very simple with a small number of behaviors and principally without the behaviors of chemical treatment, which are responsible for the fragmentation of the substrate as it is treated by with digestive enzymes. In the two species of the genus Trachymyrmex, the process became more complex and showed a greater participation of these behaviors. A. disciger, witch is a leaf cutting ant, showed an extensive specialization of physical castes in all the phases of the process which elevated it's efficiency. In the chapter about the evolution of the behaviors of brood care... (Complete abstract click electronic access below) / Doutor

The aim of this study was to reveal mechanisms of pH change in wood ant nests. Contents of basic cations and glucose brought in ant food, i.e., honeydew and prey, into the nests were measured. Manipulation experiment was carried out to test effects of glucose and Ca2+ cations brought by ants into the nest on increase in pH.

CoordenaÃÃo de AperfeiÃoamento de NÃvel Superior / Animal toxins can be a source of molecular models for the design of new drugs. This study investigated the antimicrobial and trypanocidal potential from Dinoponera quadriceps ant venom (DqV) aiming to discover therapeutic value substances. We conducted the microdilution test, where it was determined the minimum inhibitory concentration (MIC) and Minimum Lethal Concentration (MLC) over Staphylococcus aureus ATCC 6538P , Escherichia coli ATCC 10536 , Pseudomonas aeruginosa ATCC 9027 , Salmonella subsp cholearaesuis choleraesuis serotype choleraesuis ATCC 10708 and Candida albicans ATCC 10231 strains and two microbial strains of Methicillin Resistant Staphylococcus aureus (MRSA), S. aureus ATCC 33591 and S. aureus CCBH 5330. MIC and MLC of DqV were respectively 6.25 Âg/mL and 12.5 Âg/mL for S. aureus ATCC 6538P, 3.12 Âg/mL and 3.12 Âg/mL for E. coli, 12.5 Âg/mL and 12.5 Âg/mL for P. aeruginosa, 12.5 Âg/mL and 25 Âg/mL for S. choleraesuis, 25 Âg/mL and 50 Âg/mL for C. albicans, 12.5 Âg/mL and 50 Âg/mL for S. aureus CCBH 5330 and 100 Âg/mL and 100 Âg/mL for S. aureus ATCC 33591. Mechanism of action experiments were performed for the strain of S. aureus ATCC 6538P methicillin-susceptible (MSSA), that changes in the permeability of the bacterial membrane of S. aureus treated with bacteriostatic and bactericidal concentrations of DqV was observed by the crystal violet assay and release of genetic material assay. A lowest MIC was observed when alkaline pH broth was used (7,5-9,0). Complete bacterial growth inhibition was observed after 4 h of incubation with the MLC of DqV. Bacterial morphology was analyzed by atomic force microscopy after exposure of bacteria to the CIM and CIM /2 of DqV for 4 hours, showing membrane damage. In antiparasitic assays, we determined the cytotoxic effects of the venom on epimastigote and trypomastigote forms of the Y strain of Trypanosoma cruzi. In epimastigotes, cytotoxicity was evaluated at 24 and 48 h, finding IC50 of 28.32 Âg/mL and 20.67 Âg/mL, respectively. The mechanism of cell death was assessed by flow cytometry and revealed the presence of necrotic and apoptotic involvement in the cytotoxic effect of DqV over epimastigote form, in addition, the appearance of double labeled cells with PI and Annexin V-FITC, indicating the occurrence of late apoptosis. Cytotoxicity was evaluated over trypomastigote finding an IC50 of 1.978 Âg/mL and over RAW 264.7 cells finding an IC50 of 32.44 Âg/mL. The venom showed antibacterial activity against S. aureus MSSA and MRSA, P. aeruginosa, S. choleraesuis, E. coli and C. albicans, suggesting membrane damage in S. aureus ATCC 6538P. Additionally, showed cytotoxic potential on epimastigote and tripomastigote forms of Y strain of T. cruzi. / As toxinas animais podem ser fonte de modelos moleculares para o desenho de novos fÃrmacos. Este trabalho objetivou estudar o potencial antimicrobiano e tripanocida do veneno da formiga Dinoponera quadriceps (VDq) visando à descoberta de substÃncia de valor terapÃutico. Foi realizado o ensaio de microdiluiÃÃo em caldo, onde foi determinado a ConcentraÃÃo InibitÃria MÃnima (CIM) e ConcentraÃÃo Letal MÃnima (CLM) das cepas Staphylococcus aureus ATCC 6538P, Escherichia coli ATCC 10536, Pseudomonas aeruginosa ATCC 9027, Salmonella cholearaesuis subsp. choleraesuis sorotipo choleraesuis ATCC 10708 e Candida albicans ATCC 10231 e duas cepas Staphylococcus aureus Meticilina Resistente (MRSA), S. aureus ATCC 33591 e S. aureus CCBH 5330. CIM e CLM de VDq foram respectivamente 6,25 Âg/mL e 12,5 Âg/mL para S. aureus ATCC 6538P, 3,12 Âg/mL e 3,12 Âg/mL para E. coli, 12,5 Âg/mL e 12,5 Âg/mL para P. aeruginosa, 12,5 Âg/mL e 25 Âg/mL para S. choleraesuis, 25 Âg/mL e 50 Âg/mL para C. albicans, 12,5 Âg/mL e 50 Âg/mL para S. aureus CCBH 5330 e 100 Âg/mL e 100 Âg/mL para S. aureus ATCC 33591. Em seguida foram realizados experimentos de mecanismo de aÃÃo para a cepa de S. aureus ATCC 6538P SensÃvel à Meticilina (MSSA), onde se verificou alteraÃÃo na permeabilidade da membrana bacteriana de S. aureus tratado com concentraÃÃes bacteriostÃticas e bactericidas de VDq atravÃs do ensaio do cristal violeta e do ensaio de liberaÃÃo de material genÃtico. Uma menor CIM foi encontrada quando pHs alcalinos foram utilizados no teste (7,5-9,0). Uma completa inibiÃÃo de crescimento foi observada apÃs 4 h de incubaÃÃo com CLM de VDq. A morfologia bacteriana foi avaliada por microscopia de forÃa atÃmica apÃs exposiÃÃo da bactÃria à CIM e CIM/2 de VDq durante 4 h, mostrando o dano de membrana. Nos ensaios antiparasitÃrios, foram observados os efeitos citotÃxicos do veneno sobre formas epimastigotas e tripomastigotas da cepa Y de Trypanosoma cruzi. Nas formas epimastigotas, a citotoxicidade foi avaliada em 24 e 48 h, com IC50 de 28,32 Âg/mL e IC50= 20,67 Âg/mL, respectivamente. O mecanismo de morte celular foi avaliado por citometria de fluxo e revelou envolvimento necrÃtico e apoptÃtico no efeito do VDq sobre formas epimastigotas, alÃm do aparecimento de cÃlulas marcadas duplamente com PI e anexina V-FITC, indicando a ocorrÃncia de apoptose tardia. A citotoxicidade foi avaliada sobre formas tripomastigotas encontrando uma IC50 de 1,978 Âg/mL e sobre cÃlulas RAW 264.7 uma IC50 de 32,44 Âg/mL. O veneno apresentou atividade antimicrobiana sobre S. aureus MSSA e MRSA, P. aeruginosa, S. choleraesuis, E. coli e C. albicans, sugerindo lise de membrana em S. aureus ATCC 6538P. Adicionalmente, apresentou potencial citotÃxico sobre as formas epimastigota e tripomastigorta de cepa Y de T. cruzi.

This study contributes to critical studies of information systems (CRIS) by addressing two limitations: the generally weak theorisation of technology and the limited focus of critique. Technology is weakly theorised because it is mainly seen in instrumentalist and constructivist ways. It is argued that these understandings of the technological limit the focus of critique to human plans, intentions and relations. The study joins the quest for specificity about technology and while it does not only focus on what is inscribed into it, the study also looks at the effects of the technological actant. The ANT conception of technology as an actant in heterogeneous networks opens various new avenues for critique. It is argued that the processes of technologising play a central role in socio-technical networks and that they have certain effects which contribute to both change and stability. The technological could not be limited to the “purely” technical, but has effects on the typical human functions such as communication, cognition, morality and ends. Although it is acknowledged that the social and the technical are closely intertwined, critique could still focus on the role of the technical. The particular effects of technology in the heterogeneous networks are of central concern to the critical researcher who wants to contribute towards the morality of the processes through which heterogeneous networks are built. The study investigates in some depth the conceptions of technology and of critique in information studies. This is contrasted with similar investigations from an ANT perspective. Case studies were used and reinterpreted to show how such a critique of the socio-technical networks might be done. Conclusions are drawn about the nature and functioning of technology and of critique; of the role of actants in networks and of the role of the critical researcher and of critical theories. The study contributes towards a deepening and broadening of critique. The deepening of critique refers to the need for a critical function within the very processes of assembling and not as something that could only happen afterwards. The broadening of critique refers to the participation of all entities (human and nonhuman) in the processes of critique. / Thesis (PhD)--University of Pretoria, 2010. / Informatics / unrestricted