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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.
171

Parâmetros físico-químicos, polínicos e determinação de elementos-traço do mel de Meliponinae (Hymenoptera: Apidae) / Physico-chemical parameters, polinic and determination of trace elements in honey Meliponinae (Hymenoptera: Apidae)

Andreia Santos do Nascimento 11 April 2014 (has links)
O estudo teve como objetivo contribuir com a caracterização do mel das abelhas sem ferrão, especificamente a caracterização botânica e físico-química de maneira a fornecer subsídios para programas e medidas de incremento da atividade meliponícola. Foram definidos como locais de estudo municípios do Paraná (Bandeirantes, Cornélio Procópio e Guaraqueçaba), Santa Catarina (Saltinho do Canivete/Mafra) e São Paulo (Icém). As amostras, composta por 250 mL de mel, foram obtidas diretamente com os meliponicultores de acordo com o pico de produção melífera de cada região no período compreendido entre abril a dezembro de 2011 e abril a dezembro de 2012. Os parâmetros físico-químicos analisados foram: hidroximetilfurfural, pH, acidez, condutividade elétrica, cinzas, umidade, cor, açúcares redutores, sacarose e atividade diastásica. Para determinação dos elementos-traços foi utilizada a técnica de Voltametria de Redissolução Anódica de Pulso Diferencial. A análise polínica foi realizada seguindo o método padrão de acetólise e em seguida submetidas as análises quantitativas (contagem consecutiva de até 1.000 grãos de pólen/amostra) e qualitativas. Quanto aos parâmetros açúcares redutores, sacarose, hidroximetilfurfural e cinzas as amostras de mel de meliponíneos atendem aos pré-requisitos da legislação vigente. Já os parâmetros umidade e atividade diastásica divergiram. Este fato aponta a necessidade de criação de uma legislação especifica para mel das abelhas nativas levando em consideração o elevado número de espécies e suas características diferenciadas. A determinação dos elementos-traços (Cd, Cu, Pb e Zn) indica que as amostras de mel de abelhas sem ferrão apresentam concentrações não prejudiciais a saúde humana. Com análise polínica verificou-se diversidade de espécies vegetais utilizadas por essas abelhas sendo, a família Fabaceae (Caesalpinioideae, Faboideae e Mimosoideae) a que apresentou maior riqueza de tipos polínicos, seguida de por Asteraceae, Myrtaceae e Solanaceae. / The study aimed to contribute to the characterization of honey from stingless bees, specifically botany and physico-chemical characterization in order to provide support for programs and measures to increase the meliponícola activity. Were defined as study sites municipalities of Paraná (Bandeirantes, Cornélio Procópio e Guaraqueçaba), Santa Catarina (Saltinho do Canivete/Mafra) and São Paulo (Icém). The samples, consisting of 250 mL of honey, were obtained directly from the beekeepers in accordance with the peak honey production in each region for the period April to December 2011 and from April to December 2012. The physicochemical parameters analyzed were: hydroxymethylfurfural, pH, acidity, electrical conductivity, ash, moisture, color, reducing sugars, sucrose and diastase activity. For determination of trace elements technique anodic stripping voltammetry differential pulse was used. Pollen analysis was performed following the standard acetolysis method, and then subjected to quantitative analysis (row count to 1.000 pollen grains/sample) and qualitative. As for the parameters reducing sugars, sucrose, hydroxymethylfurfural and ash samples of honey from stingless bees meet the prerequisites of the current legislation. Have the parameters humidity and diastase activity diverged. This fact points out the need to create specific regulations for honey from native bees taking into account the high number of species and their different characteristics. The determination of trace elements (Cd, Cu, Pb and Zn) indicates that samples of honey from stingless bees exhibit concentrations not harmful to human health. With pollen analysis it was found diversity of plant species used by these bees being the family Fabaceae (Caesalpinioideae, Faboideae and Mimosoideae) presented the highest richness of pollen types, followed by Asteraceae, Myrtaceae and Solanaceae.
172

Imunoterapia especifica = efeitos sobre expressão de receptores de histamina, fator de liberação de histamina, GATA-3 e cadeia y do receptor de alta afinidade de IgE em celulas linfomononucleares de pacientes alergicos ao veneno de Apis mellifera / Specific immunotherapy : effects on the expression of histamine receptors, histamine releasing factors, GATA-3 and y chain of high affinity IgE receptor on lymphomononuclear cells from Apis mellifera allaergic patients

Trevizan, Giovanna 15 August 2018 (has links)
Orientador: Ricardo de Lima Zollner / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-15T13:48:19Z (GMT). No. of bitstreams: 1 Trevizan_Giovanna_M.pdf: 992041 bytes, checksum: 788bad7f2b885488c459d8cc22f66468 (MD5) Previous issue date: 2010 / Resumo: As reações alérgicas à ferroada de inseto resultam de resposta exacerbada do sistema imune, com produção de elevados níveis de anticorpos IgE alérgeno-específicos e padrão de citocinas Th2. A diferenciação de linfócitos Th2 e a secreção de citocinas por estas células são reguladas pelo fator de transcrição GATA-3. A ligação da IgE ao seu receptor de alta afinidade (Fc?RI) em mastócitos e basófilos, promove a liberação de mediadores inflamatórios. Muitos estudos demonstram a eficácia da imunoterapia específica na dessensibilização e no desenvolvimento de tolerância em indivíduos com quadros graves de hipersensibilidade à ferroada de insetos, sobretudo da classe Hymenoptera. A histamina é o principal mediador liberado durante a resposta alérgica; através da ativação de diferentes receptores (HR1, HR2, HR3 ou HR4) as células do sistema imune podem ser tanto inibidas como estimuladas. Via HR1, a histamina estimula principalmente linfócitos Th1, enquanto inibe linfócitos Th2 via HR2. O receptor 4 desempenha papel central na diferenciação de linfócitos Th2 e também é capaz de modular a produção de citocinas. A liberação de histamina é regulada por fatores de liberação de histamina (HRF), sendo que os HRF dependentes de IgE induzem a liberação de histamina na fase tardia das reações alérgicas. Considerando-se todas essas informações, o objetivo do presente trabalho foi avaliar os efeitos modulatórios da imunoterapia na expressão gênica dos receptores de histamina (HR1, HR2 e HR4), fatores de liberação de histamina (HRF) e cadeia ? do receptor de alta afinidade de IgE, além da expressão protéica do fator de transcrição GATA-3, em células linfomononucleares de pacientes alérgicos ao veneno de abelha. As células foram isoladas de pacientes submetidos à imunoterapia, em diferentes períodos do tratamento (Pré, 1, 3, 6, 12, 18 e 24 meses), após injeção subcutânea, e submetidas à cultura por 72 horas, com estimulo de veneno de abelha a 1 ng/ml. Indivíduos não alérgicos foram estudados como grupo controle. Com objetivo de avaliar a expressão gênica foram realizadas extração de RNA, seguida de síntese de cDNA e PCR, para avaliação da expressão protéica, utilizou-se a técnica de imunofluorescência. A expressão gênica de HR1 e HR4, assim como de HRF e da cadeia gama do Fc?RI foi significativamente reduzida ao final do período analisado. O receptor 2 de histamina não apresentou alterações bem definidas após 24 meses de imunoterapia. O fator de transcrição GATA-3 apresentou diminuição significativa na expressão a nível protéico. Nossos resultados demonstram que a imunoterapia específica ao veneno de abelha foi capaz de modular elementos envolvidos na resposta imune / Abstract: Allergic disease is an abnormal response from the immune system, with high levels of allergen specific IgE antibodies and Th2 pattern of cytokines. Development of Th2 cells and the production of cytokines are regulated by transcription factor GATA-3. Binding of IgE to its high affinity receptor (Fc?RI) in mast cells and basophils induces inflammatory mediators' release. Many studies have shown the efficacy of specific immunotherapy. Histamine is an important mediator in allergy, through activation of distinct histamine receptors (HR1, HR2, HR3 or HR4) in the immune system; cells can be either stimulated or inhibited. Histamine can stimulate, by HR1 receptor, especially Th1 response, and inhibit particularly Th2 cells through HR2 activation. HR4 plays a central role in Th2 polarization and also modulates cytokine profile production. IgE-dependent histamine releasing factors (IgE-HRF) induce histamine release in late phase reaction. In regard of this information, the aim of this study was to evaluate the modulating effects of specific immunotherapy in gene expression of histamine receptors (HR1, HR2 and HR4), histamine releasing factor (HRF), in patients with allergy and the gama chain of Fc?RI, and also GATA-3 protein levels. Bee venom allergic subjects underwent specific bee venom immunotherapy (VIT) in different stages of treatment (Pre, 3, 6, 12, 18 and 24 months) were studied. Peripheral blood mononuclear cells were isolated after subcutaneous venom injection and submitted to culture for 24, 48 and 72 hours stimulated with 1ng/ml of bee venom. In parallel healthy subjects were studied as well. Total RNA extraction, followed by cDNA synthesis and PCR were used to evaluate gene expression; GATA-3 protein expression was analyzed by immunofluorescence assay. Data from all time of cell culture - 24, 48 and 72 hours - were grouped and analyzed. Gene expression from HR1 and HR4 and also HRF and ? chain of Fc?RI were significantly reduced at the end of 24 months of immunotherapy. Histamine receptor 2 didn't show well established alterations. For transcription factor GATA-3 significant decrease at protein level was observed. Together, our results indicate that bee venom specific immunotherapy was able to modulate some of the elements involved in the immune response / Mestrado / Ciencias Basicas / Mestre em Clinica Medica
173

Filogenia molecular das abelhas Augochlorini (Hymenoptera, Apidae) / Molecular phylogeny of Augochlorini bees (Hymenoptera, Apidae)

Rodrigo Barbosa Gonçalves 23 May 2011 (has links)
Augochlorini (Halictinae) e um elemento comum na região Neotropical, e a historia natural das suas espécies e marcada pela plasticidade quando comparada a outras abelhas. A tribo e grupo-irmão de Halictini, e seus fosseis datam pelos menos do âmbar Dominicano (cerca de 20 milhões de anos). As relações entre os gêneros de Augochlorini foram reconstruídas de maneira insatisfatoria, sendo as hipóteses existentes em parte incongruentes, pouco robustas e baseadas apenas em dados morfológicos. Neste sentido, o presente estudo apresenta uma abordagem filogenética empregando dados moleculares. Para 76 terminais, foram obtidas sequências de DNA de quatro genes, 28S, Fator de Alongamento 1-alfa, Rodopsina Verde e wingless, somando 3043 pares de bases alinhadas. Análises de máxima parcimônia, máxima verossimilhança e inferência bayesiana foram conduzidas para os dados moleculares em conjunto, incluindo ou não regiões de alinhamento ambíguo (alças e íntrons). Os resultados, em consenso, apontam para a parafilia das duas subtribos de Augochlorini sensu Engel, com três grupos de gêneros, gr. Corynura, gr. Rhinocorynura e gr. Chlerogella formando uma politomia na base. Os demais gêneros formam um agrupamento que e dividido em três grandes clados, cujas relações não foram bem resolvidas. O primeiro e composto pelo grupo Megaloptidia e os gêneros Augochloropsis, Augochlorodes e Pseudaugochlora, o segundo pelo grupo Neocorynura mais Chlerogas, Paroxystoglossa e Temnosoma, e o terceiro pelo grupo Augochlora e Caenaugochlora, Megalopta e Thectochlora. As primeiras linhagens de Augochlorini se diversificaram entre 7060 milhões de anos atrás, sendo que desde 50 milhões de anos vem ocorrendo uma gradativa diversificação do grupo. A re-análise da morfologia externa do grupo não foi útil para entender melhor a evolução do grupo que em trabalhos anteriores, inclusive diminuindo o poder explicativo da hipótese gerada pela evidencia total. As hipóteses moleculares apresentaram novas evidencias que guiam futuros estudos para o grupo, para que se possa entender a evolução dentro de cada um dos seus clados. / Augochlorini (Halictinae) is a common element in the Neotropical region, and his natural history is known by their relatively plasticity when compared to other bees. Augochlorini is sister-group of Halictini, and its oldest fossils date from the Dominican amber (about 20 million years before present). The phylogenetic relationships among their genera were only superficially reconstructed, the competing hypothesis are not entirely congruent nor robust and were based only on morphological data. With this background, this study aims to present a molecular phylogeny to Augochlorini. It was obtained, for 76 terminals, DNA sequences of four genes, 28S, Elongation Factor 1-alpha, Green Rodopsin and Wingless, giving a 3043 base pair alignment. Maximum parsimony, maximum likelihood and Bayesian inference analyses were carried out for the molecular data, including or excluding regions of ambiguous alignment (loops and introns). The results, based on consensus trees, suggest the paraphyly of both Augochlorini subtribes (sensu Engel), with three groups of genera, gr. Corynura, gr. Rhinocorynura e gr. Chlerogella forming a basal polytomy with a clade containing the remaining genera. This clade has three subgroups, whose phylogenetic relationships were not well stabilized. The first group consists of gr. Megaloptidia and Augochloropsis, Augochlorodes, and Pseudaugochlora, the second group of gr. Neocorynura plus Chlerogas, Paroxystoglossa, and Temnosoma, and the third group consists of gr. Augochlora and Caenaugochlora, Megalopta, and Thectochlora. The first Augochlorini lineages diversified by 70 to 60 million years ago, and since 50 mya there has been a gradual diversification of the group. The reanalysis of augochlorines external morphology was not helpful for understanding the evolution of the group, and also reduced the explanatory power of the total evidence hypothesis. The molecular hypothesis brought new evidences to guide future studies for the group, and positively favored the conception about the evolution of Augochlorini main clades.
174

Visitantes florais de clones precoces do eucalipto urograndis (Eucalyptus grandis x Eucalyptus urophylla) e as características de néctar como indicativo de seu potencial apícola / Floral visitors of early clones of eucalyptus urograndis (Eucalyptus grandis x E. urophylla), and nectar characteristics as an indicative of beekeeping potential

José Wilson Pereira da Silva 16 April 2010 (has links)
A comunidade de insetos visitantes de flores de clones do eucalipto urograndis (Eucalyptus grandis x E. urophylla) foi estudada em um plantio localizado na Fazenda Areão, em Piracicaba, SP (22° 41 41 S e 47° 38 5 3 W ) por meio de levantamentos semanais com rede entomológica, durante os florescimentos de 2007 e de 2008 com a finalidade de caracterizar seu potencial apícola com a determinação de sua apifauna associada, e das características de néctar produzidos por suas flores. A comunidade antófila nos dois anos do levantamento foi representada por 29.492 indivíduos pertencentes a 6 ordens, 21 famílias, 43 gêneros e 52 espécies. A apidofauna foi representada por 24.882 indivíduos pertencentes a 11 gêneros e 10 espécies. A abelha africanizada Apis mellifera, o visitante mais efetivo em todo o levantamento (80,96%), seguida do sirfídeo Ornidia obesa (5,29%) e do mantispídeo Zeugomantispa virescens (4,26%). Os índices de diversidade (H) e equitabilidade (E); foram distintos nos dois levantamentos indicando distribuição de espécies mais uniforme na coleta de 2007 em relação à de 2008. Dentre as demais espécies predominantes, destacaram-se as abelhas Trigona spinipes (irapuá), Tetragonisca angustula (jataí), e Nannotrigona testaceicornis (iraí). As concentrações médias encontradas por clones foram inferiores ao relatado na literatura, sendo os valores máximos variando entre 13 e 14%. As diferenças encontradas entre alguns clones possivelmente foram influenciadas pela altura de algumas plantas. / The community of insect flower visitors of eucalyptus urograndis clones (Eucalyptus grandis x E. urophylla) was studied in an plantation located at Areão farm, in Piracicaba, São Paulo state, Brazil (22° 41 41 S e 47° 38 53 W ). Weekly collections were conducted using hand net during the bloom periods of 2007 and 2008 in order to characterize the potential for beekeeping by determining the associated apifauna and the nectar characteristics produced by the flowers.The anthophilous community in the two-year survey was represented by 29,492 individuals belonging to 6 orders, 21 families, 43 genera and 52 species. The apidofauna was represented by 24,882 individuals belonging to 11 genera and 10 species. The Africanized honey bee Apis mellifera. This species was the most effective visitor throughout the survey (80.96%) followed by the syrphid Ornidia obesa (5.29%) and the mantispid Zeugomantispa virescens (4.26%). The diversity (H\') and equitability (E) indices were different between the two surveys showing that species distribution was more uniform in the collecting of 2007 when compared to the 2008. Among the other dominant species, the bees Trigona spinipes (Irapuá bee), Tetragonisca angustula (jataí bee), and Nannotrigona testaceicornis (Iraí bee) were the main ones. The differences found between some clones were possibly influenced by the height of some plants.
175

Brood cycles in queenless colonies of Apis mellifera capensis

Crous, Kendall Lauren January 2010 (has links)
In a honeybee colony, the loss of a queen is considered to be a serious occurrence and, if a new queen is not produced, ultimately doomed. However, in colonies of Apis mellifera capensis (Cape honeybees), numerous pathways are available for a colony which unexpectedly losses a queen. At the onset of this experiment, four colonies of A. m. capensis were dequeened. Following this photographs of all brood frames in each colony were taken and the contents of the cells analysed. Cells were chosen at random but once selected were repeatedly analysed for the duration of the experiment. The contents of a total of 44 888 individual cells were analysed. Any queen cells constructed during the sampling period were removed, maintaining a queenless state. In each colony, as predicted, the removal of the queen evoked a variety of responses in an attempt to rectify the sudden loss. However, ultimately three of the four colonies absconded, leaving little by way of stores. Three of the four colonies initially attempted to rear a new queen while one colony was immediately invaded by a presumed foreign queen and hence any attempt at queen cell construction ceased. An increased number of queen cells in the swarm position were recorded in all colonies. The invasion of a colony by a foreign queen was considered to be a new pathway available for queenless colonies of A.m capensis. Worker policing and suspected brood cannibalism was prevalent in all sampled colonies yet in addition, the transfer of eggs and larvae from cell to cell was also observed which may have increased the suspected cases of policing and cannibalism. It was unclear whether an egg or larva had been consumed or simply moved to another cell on the brood frame. All colonies contained eggs from laying workers to varying degrees, based on the length of each individual sampling period which varied between colonies due to differences in absconding dates. A steady breakdown in the effectiveness of the division of labour amongst the worker bees was observed in each of the colonies highlighting the vital role of a queen. This breakdown was clearly seen in the reduction in general housekeeping within a colony. An increase in stores indicated a possible increase in the number of forager bees, thereby reducing the number of worker bees available for other duties. Pathways available to broodright colonies and strategies used following sudden queen loss are discussed.
176

Estrutura e diversidade genética de populações insulares e continentais de abelhas da Mata Atlântica / Genetic structure and diversity of island and mainland populations of bees from Atlantic forest

Flavio de Oliveira Francisco 22 October 2012 (has links)
Durante muito tempo as ilhas vêm sendo fundamentais para pesquisa em ecologia e biologia evolutiva. Esses estudos tornaram possível a elaboração de importantes teorias nesses campos e que puderam ser extrapoladas para diversos outros ambientes. O aumento dos desmatamentos e da fragmentação de habitats tem levado ao isolamento dos organismos em \"ilhas\" dentro do continente. A perda de diversidade em fragmentos é uma situação preocupante. Populações restritas a ilhas ou fragmentos possuem maior probabilidade de extinção. As abelhas possuem um papel fundamental nos ecossistemas e por isso a extinção de uma população terá impacto nos outros níveis tróficos. Em virtude disso, o objetivo desse trabalho foi testar a hipótese de que populações das abelhas Tetragonisca angustula e Bombus morio de ilhas com mais de 100 ha localizados nos estados de Santa Catarina (SC), Paraná (PR), São Paulo (SP) e Rio de Janeiro (RJ), e populações continentais em áreas próximas a remanescentes de Mata Atlântica nos estados de Minas Gerais (MG), PR, RJ, SC e SP possuem baixa diversidade genética e, por isso, estariam mais propensas à extinção. Nossos resultados mostraram que a espécie T. angustula apresenta alta filopatria de rainhas e baixa diversidade genética mitocondrial. Por outro lado, os microssatélites mostraram menor estruturação e alta/moderada diversidade genética, indicando que os machos são o sexo dispersor. Para a espécie B. morio, a diversidade genética observada para ambos os marcadores foi alta, com exceção de duas populações. As fêmeas também apresentaram maior estruturação populacional, enquanto que para os machos essa estruturação praticamente não existiu. Portanto, as populações das espécies T. angustula e B. morio não apresentam inclinação à extinção. A sobrevivência em ambientes urbanos e a grande capacidade de migração dos machos parecem ser fatores fundamentais para isso. Além disso, essas características parecem ser as responsáveis pelo não isolamento genético entre muitas das populações geograficamente isoladas / Islands have been key research fields on the ecology and evolutionary biology for a long time. The study of their biota has made possible the development of important theories that could be extrapolated to other environments. The increase in deforestation and habitat fragmentation has led to isolation of the organisms in \"islands\" within the continent. Loss of diversity in fragments is a concern, because nowadays many species only exist in fragments. Populations restricted to islands or fragments have higher probability of extinction. Bees have a key role in ecosystems and the extinction of their populations will impact other trophic levels. The aim of this study was to test the hypothesis that populations of two bee species, Tetragonisca angustula and Bombus morio, in islands with more than 100 ha located in the states of Santa Catarina (SC), Paraná (PR), São Paulo (SP) and Rio de Janeiro (RJ), and mainland populations in areas near the Atlantic Forest remnants in the states of Minas Gerais (MG), PR, RJ, SC and SP have low genetic diversity and therefore would be more prone to extinction. Our results to T. angustula showed low mitochondrial genetic diversity which can be associated to queen philopatry behavior. Moreover, microsatellites showed lower structure and moderate/high genetic diversity, indicating a greater dispersion by males. The genetic diversity observed for B. morio for both markers was high, excepting two populations. Females also had higher population structure than detected for males. Therefore, most of T. angustula and B. morio populations are not prone to extinction, mainly because of their capability to survive in urban environments and high male migration. Therefore, these characteristics seem to be responsible for allowing many of the geographically isolated populations do not present genetic isolation
177

Metody značení těla a potravy hmyzu a jejich využití u včel (Anthophila) / Methods of insect body and food marking and their utilization in bees (Anthophila)

Macháčková, Lenka January 2021 (has links)
Marking methods represent often an essential part of many studies which target on insect biology. These marking techniques sometimes represent the only possible way to obtain new and important informations. In the first part of the thesis I deal with individual insect labeling, which was used for marking of solitary bees and their nests as a tool of obtaining informations about nesting bee dynamics in aggregation. Our study show that nest owner replacements are very common in all four species. However, a large percentage of the nests were abandoned by the female owners before owner change. Only a part of all the nests were trully usurped on the nesting site. The true usurpations thus represent rather minor part of observed nest owner replacement situations. The bees surprisingly often abandon their nests and found the new ones. The frequent contacts of the females on a nesting site occur as a result of common nest owner replacements. High tolerance of bees to each other together with tolerance of usurpations and low level of aggression may thus represent one of the possible ways towards communality and other types of social behaviour. In the second part of the thesis I focus on the possibilities of food marking in bees. Effectivity of sugar and pollen utilization are not yet fully understood in...
178

Právní úprava včelařství / Legal regulation of beekeeping

Kotrba, Jiří January 2021 (has links)
1 Abstract This diploma thesis deals with legal issues related to beekeeping and bee protection. The beekeeping legislation in Czech Republic is not regulated in just one comprehensive legal act but consists of many partial provisions that can be found in a large number of various acts and decrees. The fragmentation of the beekeeping legislation is its biggest shortcoming and causes, that beekeepers are unable to get proper knowledge of the issue. It is necessary to ensure that all beekeepers are informed as best as possible of their rights and obligations, so that the legislation is followed in practice. Reader of this thesis is being presented with a detailed legal analysis of the most important provisions concerning beekeeping which is also here and there accompanied with ideas de lege ferenda. This diploma thesis is divided into five parts, which are further subdivided into chapters and also into subchapters and lower levels if needed. The first part is divided into two chapters and discusses the history of beekeeping and the beginnings of the development of its legal regulation in the world and in the territory of the Czech state. The second part of this diploma thesis is subdivided into three chapters and deals with the considerations about the possible future extension of the legal regulation which...
179

Immunological and Gene Regulatory Functions of the Protein Vitellogenin in Honey Bees (Apis mellifera)

January 2019 (has links)
abstract: Vitellogenin (Vg) is an ancient and highly conserved multifunctional protein. It is primarily known for its role in egg-yolk formation but also serves functions pertaining to immunity, longevity, nutrient storage, and oxidative stress relief. In the honey bee (Apis mellifera), Vg has evolved still further to include important social functions that are critical to the maintenance and proliferation of colonies. Here, Vg is used to synthesize royal jelly, a glandular secretion produced by a subset of the worker caste that is fed to the queen and young larvae and which is essential for caste development and social immunity. Moreover, Vg in the worker caste sets the pace of their behavioral development as they transition between different tasks throughout their life. In this dissertation, I make several new discoveries about Vg functionality. First, I uncover a colony-level immune pathway in bees that uses royal jelly as a vehicle to transfer pathogen fragments between nestmates. Second, I show that Vg is localized and expressed in the honey bee digestive tract and suggest possible immunological functions it may be performing there. Finally, I show that Vg enters to nucleus and binds to deoxyribonucleic acid (DNA), acting as a potential transcription factor to regulate expression of many genes pertaining to behavior, metabolism, and signal transduction pathways. These findings represent a significant advance in the understanding of Vg functionality and honey bee biology, and set the stage for many future avenues of research. / Dissertation/Thesis / Doctoral Dissertation Evolutionary Biology 2019
180

The History and Population Genomics of Managed and Feral Honey Bees (Apis mellifera L.) in the United States

Madeline Hansen Carpenter (12482184) 30 April 2022 (has links)
<p>    </p> <p>Domestication is the process by which a previously wild population is managed by humans, thereby being subjected to a different set of selective pressures than experienced in its natural setting. Its opposite, feralization, is therefore when a domesticate escapes or is released from a captive setting, reasserting natural selective pressures. The genomics underpinning both domesti- cation and feralization have not been studied in insects; the Western honey bee (<em>Apis mellifera </em>L.) is a good model for this system, as honey bees exist in both a managed and feral state, and have extensive historic and genomic resources to document population changes. My goal in this thesis was to 1) improve upon our understanding of honey bee importation and genetics to the United States to support demographic assertions, and 2) to sequence managed and feral stocks of honey bees to identify the population structure and 3) genetic differences underpinning domestication. Ultimately, I reconstructed 400 years of honey bee importation and management history, creating the most comprehensive understanding to date of importation dates and locations, historical man- agement practices, and genetic bottlenecks. Additionally, I summarized thirty years of honey bee genome sequencing to provide a road map for future studies. Then, I conducted whole genome pooled sequencing on six managed and three feral stocks of honey bees from the United States. The mitochondrial and whole genome ancestry of feral colonies holds relics from their importation history, while managed colonies show evidence of more recent importation events. The managed stocks in my sample set have higher overall genetic diversity, but exhibit little differentiation, but feral stocks exhibit varying levels of differentiation, indicating different levels of ferality likely dictated by the level of reproductive isolation from managed colonies. </p>

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