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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.
81

Obtenção artificial de rainhas e estabelecimento de novas colônias de Tetragona clavipes (Hymenoptera, Apidae, Meliponini) / Artificial obtainment of queens and establishment of new colonies of Tetragona clavipes (Hymenoptera, Apidae, Meliponini)

Castro, Ivan de 22 June 2012 (has links)
A criação racional de abelhas sem ferrão, conhecida como meliponicultura, é uma atividade crescente no Brasil e sua demanda abriu o campo para pesquisas que favorecem esse mercado. Além disso, o papel essencial desempenhado por esses insetos na polinização tem chamado atenção para o seu uso sustentável na prática agrícola. Nesses aspectos, alguns trabalhos são direcionados à aquisição de conhecimento básico sobre a biologia dessas abelhas que embasem técnicas de manejo e aprimoramento da sua criação. Um fator crucial é a multiplicação de colmeias em um intervalo de tempo menor a partir da obtenção artificial de rainhas, que foi o foco deste trabalho. A espécie aqui envolvida, Tetragona clavipes, tem distribuição ampla em território brasileiro e um potencial relevante no fornecimento de produtos como mel, pólen, cera e resinas, apesar dos poucos dados sobre seu manejo na literatura afim. Sua diferenciação de castas depende da quantidade de alimento ingerido durante a fase larval. A primeira parte da pesquisa envolveu a criação de larvas in vitro, onde foi caracterizada a quantidade limiar de alimento larval para diferenciação de castas: entre 45 e 50 µL. Nessas condições emergiram operárias e rainhas; entre 20 e 40 µL, apenas operárias e a partir de 60 até 110 µL, apenas rainhas. Houve mortalidade alta das larvas, com média de 40%, sendo o controle de umidade relativa o ponto crítico. A segunda parte do trabalho envolveu a formação de minicolônias, em que grupos de operárias jovens (aproximadamente 50) foram mantidos com rainhas virgens em caixas pequenas. 26 minicolônias foram montadas, dentre estas, 5 com rainhas naturais. Somente duas rainhas naturais foram fecundadas e tiveram sucesso na fundação dos ninhos. Nesses dois casos o número de operárias utilizado foi maior (em torno de 200) e com idades diferentes. O principal fator que limitou essa etapa foi a agressividade das operárias durante a fase para aceitação das rainhas virgens. Nesse ponto, a estratégia mais eficiente foi a introdução de rainhas, ainda em fase de pupa, dentro de cápsulas de cerume da própria minicolônia, apesar de não terem permanecido nas caixas mesmo depois de terem sido aceitas. Uma análise por morfometria geométrica, com os programas de computador tpsDig e MorphoJ, mostrou a diferença no padrão de venação entre as asas de operárias e rainhas obtidas em laboratório. Em todas as colônias observadas foi constatada a presença de um fungo que se desenvolve naturalmente no interior das células de cria, cujas hifas são ingeridas pela larva. Entretanto, não foi possível o seu isolamento em meio de cultivo. Apesar do número pequeno de ninhos novos formados, o estudo desta espécie possibilitou a aquisição de dados importantes para a continuidade das pesquisas e também para conduzir seu manejo mais eficiente, acrescentando informações até então desconhecidas sobre sua biologia e seu comportamento. / The rational creation of stingless bees, known as meliponiculture in Brazil, is a growing activity and its demand opened the field for research and many works that favor this market. Moreover, the essential role played by these insects as pollinators has drawn attention for its sustainable use in crop pollination. In these respects, some studies are directed to the acquisition of basic knowledge about the biology of these bees which to base management techniques and improvement on its creation. A crucial factor is the multiplication of hives in a shorter interval of time by the artificial obtainment of queens, which is the focus of present work. The species involved here was Tetragona clavipes, which has a wide distribution in Brazil and a significant potential to supply products such as honey, pollen, wax and resins, despite the few data about its management in the related literature. Its caste differentiation depends only on the amount of larval food ingested at the larval stage. The first step of the research involved the development of larvae in vitro, when was characterized the amount of larval food that is the threshold for its caste differentiation: between 45 and 50 µL. In these conditions workers and queens emerge; between 20 and 40 µL, only workers and from 60 to 110 µL, only queens. There was a high mortality of larvae with an average of 40%, where the control of relative humidity was the critical point. The second part of the work involved the attempted to form mini colonies, where groups of young workers (aroud 50) with virgin queens were kept in small boxes. 26 mini colonies were assembled, among these, five with virgins natural queens. Only two natural queens were fertilized and founded nests with success. In these cases the number of workers put inside box was higher (around 200) and with different ages. The main factor that had limited this step was the aggressiveness of the workers during the acceptance of the virgin queens. At this point, the most effective strategy was the introduction of queens still in the pupal stage, inside capsules of cerumen from the own mini colonies, despite not having stayed in the boxes probably by other reasons, even when already were accepted. Additional analysis using geometric morphometrics, with the computer programs tpsDig and MorphoJ, showed a difference in the pattern of wing venation between workers and queens obtained in laboratory. In all colonies observed also was found the presence of a fungus that grows naturally inside of brood cells, whose hyphae are ingested by the larvae. However, it could not be isolated in culture medium. Despite the small number of new nests acquired, the study of this species allowed the acquisition of important data for further research and also to conduct its management more efficient, adding previously unknown details about its biology and behavior.
82

Technical Verification and Validation of TIS-B using VDL Mode 4

Fredriksson, Daniel, Schweitz, Anders January 2004 (has links)
<p>This report is a technical verification and validation of Traffic Information Service Broadcast (TIS-B) using the data link VDL Mode 4. </p><p>The main objective of the report is to examine the usefulness of TIS-B considering the results from tests performed in the Stockholm Terminal Area and for the Advanced Surface Movement Guidance and Control System (A-SMGCS) at Arlanda airport. The results are compared with the requirements that have been set by the standardisation organisations ICAO, RTCA, Eurocontrol and Eurocae. TIS-B is however such a new concept, so most of the operational requirements have not yet been defined.</p><p>The process for performing the evaluation of TIS-B involves three stages: </p><p>· Study the requirements on TIS-B, ADS-B, radar and A-SMGCS. </p><p>· Verify TIS-B by performing tests at Arlanda airport. </p><p>· Validate the test results through analysis. </p><p>A theoretical study of slot allocation optimisation is performed to decide how the slot allocation is to be implemented. </p><p>The report includes a Functional Hazard Analysis (FHA). The FHA is done to see if the applications for TIS-B are ready for implementation or if more hazard preventing actions has to be taken, before any operational actions can be performed. </p><p>The report also involves a theoretical introduction to Air Traffic Management (ATM), Surveillance techniques and TIS-B. </p><p>All parts included in the report results in conclusions and recommendations regarding the TIS-B service.</p>
83

Technical Verification and Validation of TIS-B using VDL Mode 4

Fredriksson, Daniel, Schweitz, Anders January 2004 (has links)
This report is a technical verification and validation of Traffic Information Service Broadcast (TIS-B) using the data link VDL Mode 4. The main objective of the report is to examine the usefulness of TIS-B considering the results from tests performed in the Stockholm Terminal Area and for the Advanced Surface Movement Guidance and Control System (A-SMGCS) at Arlanda airport. The results are compared with the requirements that have been set by the standardisation organisations ICAO, RTCA, Eurocontrol and Eurocae. TIS-B is however such a new concept, so most of the operational requirements have not yet been defined. The process for performing the evaluation of TIS-B involves three stages: · Study the requirements on TIS-B, ADS-B, radar and A-SMGCS. · Verify TIS-B by performing tests at Arlanda airport. · Validate the test results through analysis. A theoretical study of slot allocation optimisation is performed to decide how the slot allocation is to be implemented. The report includes a Functional Hazard Analysis (FHA). The FHA is done to see if the applications for TIS-B are ready for implementation or if more hazard preventing actions has to be taken, before any operational actions can be performed. The report also involves a theoretical introduction to Air Traffic Management (ATM), Surveillance techniques and TIS-B. All parts included in the report results in conclusions and recommendations regarding the TIS-B service.
84

Obtenção artificial de rainhas e estabelecimento de novas colônias de Tetragona clavipes (Hymenoptera, Apidae, Meliponini) / Artificial obtainment of queens and establishment of new colonies of Tetragona clavipes (Hymenoptera, Apidae, Meliponini)

Ivan de Castro 22 June 2012 (has links)
A criação racional de abelhas sem ferrão, conhecida como meliponicultura, é uma atividade crescente no Brasil e sua demanda abriu o campo para pesquisas que favorecem esse mercado. Além disso, o papel essencial desempenhado por esses insetos na polinização tem chamado atenção para o seu uso sustentável na prática agrícola. Nesses aspectos, alguns trabalhos são direcionados à aquisição de conhecimento básico sobre a biologia dessas abelhas que embasem técnicas de manejo e aprimoramento da sua criação. Um fator crucial é a multiplicação de colmeias em um intervalo de tempo menor a partir da obtenção artificial de rainhas, que foi o foco deste trabalho. A espécie aqui envolvida, Tetragona clavipes, tem distribuição ampla em território brasileiro e um potencial relevante no fornecimento de produtos como mel, pólen, cera e resinas, apesar dos poucos dados sobre seu manejo na literatura afim. Sua diferenciação de castas depende da quantidade de alimento ingerido durante a fase larval. A primeira parte da pesquisa envolveu a criação de larvas in vitro, onde foi caracterizada a quantidade limiar de alimento larval para diferenciação de castas: entre 45 e 50 µL. Nessas condições emergiram operárias e rainhas; entre 20 e 40 µL, apenas operárias e a partir de 60 até 110 µL, apenas rainhas. Houve mortalidade alta das larvas, com média de 40%, sendo o controle de umidade relativa o ponto crítico. A segunda parte do trabalho envolveu a formação de minicolônias, em que grupos de operárias jovens (aproximadamente 50) foram mantidos com rainhas virgens em caixas pequenas. 26 minicolônias foram montadas, dentre estas, 5 com rainhas naturais. Somente duas rainhas naturais foram fecundadas e tiveram sucesso na fundação dos ninhos. Nesses dois casos o número de operárias utilizado foi maior (em torno de 200) e com idades diferentes. O principal fator que limitou essa etapa foi a agressividade das operárias durante a fase para aceitação das rainhas virgens. Nesse ponto, a estratégia mais eficiente foi a introdução de rainhas, ainda em fase de pupa, dentro de cápsulas de cerume da própria minicolônia, apesar de não terem permanecido nas caixas mesmo depois de terem sido aceitas. Uma análise por morfometria geométrica, com os programas de computador tpsDig e MorphoJ, mostrou a diferença no padrão de venação entre as asas de operárias e rainhas obtidas em laboratório. Em todas as colônias observadas foi constatada a presença de um fungo que se desenvolve naturalmente no interior das células de cria, cujas hifas são ingeridas pela larva. Entretanto, não foi possível o seu isolamento em meio de cultivo. Apesar do número pequeno de ninhos novos formados, o estudo desta espécie possibilitou a aquisição de dados importantes para a continuidade das pesquisas e também para conduzir seu manejo mais eficiente, acrescentando informações até então desconhecidas sobre sua biologia e seu comportamento. / The rational creation of stingless bees, known as meliponiculture in Brazil, is a growing activity and its demand opened the field for research and many works that favor this market. Moreover, the essential role played by these insects as pollinators has drawn attention for its sustainable use in crop pollination. In these respects, some studies are directed to the acquisition of basic knowledge about the biology of these bees which to base management techniques and improvement on its creation. A crucial factor is the multiplication of hives in a shorter interval of time by the artificial obtainment of queens, which is the focus of present work. The species involved here was Tetragona clavipes, which has a wide distribution in Brazil and a significant potential to supply products such as honey, pollen, wax and resins, despite the few data about its management in the related literature. Its caste differentiation depends only on the amount of larval food ingested at the larval stage. The first step of the research involved the development of larvae in vitro, when was characterized the amount of larval food that is the threshold for its caste differentiation: between 45 and 50 µL. In these conditions workers and queens emerge; between 20 and 40 µL, only workers and from 60 to 110 µL, only queens. There was a high mortality of larvae with an average of 40%, where the control of relative humidity was the critical point. The second part of the work involved the attempted to form mini colonies, where groups of young workers (aroud 50) with virgin queens were kept in small boxes. 26 mini colonies were assembled, among these, five with virgins natural queens. Only two natural queens were fertilized and founded nests with success. In these cases the number of workers put inside box was higher (around 200) and with different ages. The main factor that had limited this step was the aggressiveness of the workers during the acceptance of the virgin queens. At this point, the most effective strategy was the introduction of queens still in the pupal stage, inside capsules of cerumen from the own mini colonies, despite not having stayed in the boxes probably by other reasons, even when already were accepted. Additional analysis using geometric morphometrics, with the computer programs tpsDig and MorphoJ, showed a difference in the pattern of wing venation between workers and queens obtained in laboratory. In all colonies observed also was found the presence of a fungus that grows naturally inside of brood cells, whose hyphae are ingested by the larvae. However, it could not be isolated in culture medium. Despite the small number of new nests acquired, the study of this species allowed the acquisition of important data for further research and also to conduct its management more efficient, adding previously unknown details about its biology and behavior.

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