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

A simulation model for the colonial development of Paravespula vulgaris (Linnaeus) and Dolichovespula sylvestris (Scopoli) (Hymenoptera:Vespidae)

Archer, M. A. January 1979 (has links)
No description available.
2

Signalizace při vývoji bakteriálních kolonií / Signalization in the ontogeny of bacterial colonies

Čepl, Jaroslav January 2010 (has links)
Bacterial bodies (colonies) can develop complex patterns of color and structure. These patterns may arise as a result of both colony-autonomous processes (self-patterning) and environmental influences, including those generated by neighbor bodies. We have studied the interplay of intra-colony signaling (self-patterning) and inter-colony influences in related clones of Serratia rubidaea on rich media. We show that the mutual influencing of colonies, present in a common morphospace, is communicated by at least two putative signals. A model accounting for some aspects of colony morphogenesis and inter-colony interactions is proposed. Key words bacteria; Serratia sp.; airborne signals; colony morphogenesis
3

Produkce amoniaku koloniemi mutantů a stárnutí strukturovaných kolonií Saccharomyces cerevisiae / Ammonia production by colonies of mutants and aging of wrinkled colonies of Saccharomyces cerevisiae

Nedbálková, Jana January 2010 (has links)
Production of ammonia by the colonies of mutants and aging of wrinkled colonies of Saccharomyces cerevisiae The aim of this diploma thesis is to observe the development, respectively the aging of cells in yeast colonies Saccharomyces cerevisiae. Yeast cells S. cerevisiea form multicellular organized structures on a solid substrate, i.e. colonies, which the intercellular interactions occur in. These interactions influence forming, morphology and aging of yeast colonies. This diploma thesis is focused partly on the changes in ammonia production by giant colonies of deletion mutants and partly on the aging of colonies with the wrinkled morphology. I characterized mutant strains of S. cerevisiae with the deletion in RTG1, RTG2, RTG3, FIS1, CIT2 genes. Their products play an important role in the colony development. The transcription of these genes changes during the transition from the acidic to alkali phase during developmental process of the colonies. I have found out that the ammonium production rate was in accordance with the results of the alkalization in giant colonies surroundings and mentioned mutants derived from the BY strain has been producing ammonia since the 15th day. The rate of the ammonia production by rtg3∆ strain was comparable to the parental strain. Compared to parental strain, lower...
4

Morfogeneze a vzájemné ovlivňování bakteriálních kolonií / Morphogenesis of the bacterial colonies and their mutually influencing

Rieger, Tomáš January 2017 (has links)
This thesis follows previous works of our group (Rieger T. et al., 2008; Cepl J. et al., 2010 and Patkova I. et al., 2012), where we focused on the morphology of the bacterial colonies Serratia marcescens and its variety caused by changing of the inoculation conditions on nutrient agar. When bacterial colonies S. marcescens are grown on nutrient agar enriched with glucose isolated enough from other colonies in its living space, it can form coloured structured colonies, which we named morphotype "fountain" (F). This morpotype becomes ideal for following studies of mutual influencing of the bacterial colonies, because of its ability of pigmentation change or structure loss caused by altering surrounding inoculation conditions. We noticed in normal sowed agar plates, that bacterial colonies, which grows in the close distance with other colonies develop their pigmentation sooner, than colonies, that grows more isolated. We studied how is this influencing happening and what are the necessary conditions for it. We proved, that different species of bacterial macrocolonies (S. marcescens - morphotype (M), S. rubidea and E. coli) emits into the nutrient agar informative signal, which makes the recipient colonies S. marcescens reacts on this signal with the same manner (X structure). It looks, that this is...
5

MICROSPECTROPHOTOMETRIC ANALYSIS OF MITOSIS AND DNA SNYTHESIS ASSOCIATED WITH COLONY FORMATION IN PEDIASTRUM BORYANUM (CHLOROPHYCEAE)

Millington, William F., Rasch, Ellen M. 01 January 1980 (has links)
Patterns of DNA synthesis and mitosis in the coenobial alga Pediastrum boryanum (Turp.) Meneghini were analyzed by cytophotometric measurements of individual, Feulgen‐stained nuclei from swarming zoospores aggregating into colonies, and cells in colonies varying in age from 12 to 96 h after their initial transfer to fresh culture medium. A haploid genome size of 0.2 pg DNA (corresponding to roughly 11 × 1012 daltons, or 1.64 × 105 kb) was estimated by comparative measurements of nuclei from zoospores or young colonies and chicken erythrocyte (RBC) nuclei which were included with each set of Pediastrum slides as an internal reference standard of 2.5 pg DNA/cell. Although nuclear morphology and extent of chromatin condensation vary with different stages of colony development, nuclear division in P. boryanum appears to follow each cycle of DNA replication with no accumulation of DNA beyond the 2C level. Cytoplasmic cleavage resulting in the formation of individual zoospores is delayed until completion of mitosis, as is the demise of the pyrenoid. After 96 h of culture, 40% of all colonies have cells that are 8‐ or 16‐nucleate and some colonies have 32 nuclei/cell. Release of zoospores within vesicles occurs at this time to complete a cycle of asexual reproduction.
6

O pontecial da mamoneira (Ricinus Communis L.) para a exploraÃÃo apÃcola: produÃÃo, toxidez e qualidade de mel e pÃlen / The pontecial of mamoneira (Ricinus Communis L.) for holding apÃcola: production, toxidez and quality of honey and pÃlen.

Marcelo de Oliveira Milfont 28 February 2007 (has links)
FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / A pesquisa de campo foi conduzida no NÃcleo de ProduÃÃo ComunitÃria Santa Clara, pertencente a empresa Brasil Ecodiesel, no municÃpio de Canto do Buriti â PI, entre maio e julho de 2006. As anÃlises laboratoriais foram realizadas nos LaboratÃrios da Universidade Federal do CearÃ, Universidade de Fortaleza, Grupo Edson Queiroz e Instituto Centro de Ensino TecnolÃgico (CENTEC) do Cariri. Os experimentos foram realizados com o objetivo de investigar a possibilidade de agregar valor a cultura da mamona (Ricinus communis) por meio da apicultura. Os seguintes aspectos foram investigados: desenvolvimento de colÃnias de Apis mellifera em meio a plantio de mamoneira; potencial da mamoneira para a produÃÃo de mel por abelhas A. mellifera; possÃvel toxidez do pÃlen e/ou nÃctar da mamoneira para abelhas melÃferas e humanos; caracterÃsticas fÃsico-quÃmicas e organolÃpticas do mel de mamona e potencial comercial deste mel. Os resultados mostraram que a cultura da mamoneira oferece boas condiÃÃes de desenvolvimento para colÃnias de A. mellifera uma vez que oferece pÃlen e nÃctar, e que estes sÃo prontamente utilizados pelas abelhas; a mamoneira mostrou-se uma importante fonte de nÃctar para a exploraÃÃo apÃcola, tendo sido produzido em apenas 49 dias medias entre 18,82 kg (apiÃrio em Ãrea de cultivo limpo de mamona) e 23,52 kg (apiÃrio em Ãrea de mamona com ervas silvestres) de mel, semelhantes à mÃdia anual do paÃs. O pÃlen e o mel da mamoneira nÃo sÃo tÃxicos para abelhas melÃferas e para roedores, indicando que, provavelmente, seja prÃprio para o consumo humano. O mel da mamoneira apresenta caracterÃsticas fÃsico-quÃmicas dentro da legislaÃÃo brasileira e caracterÃsticas organolÃpticas bem aceitas pela populaÃÃo, demonstrando que o mesmo possui potencial comercial. Conclui-se que a exploraÃÃo apÃcola da cultura da mamona pode aumentar a rentabilidade das Ãreas de cultivo e minimizar os impactos ecolÃgicos da agricultura, alÃm de gerar um produto natural, nutritivo e bem aceito pela populaÃÃo em geral. / The research was carried out in the NÃcleo de ProduÃÃo ComunitÃria Santa Clara, belonging to the company Brasil Ecodiesel, in the county of Canto do Buriti, state of PiauÃ, Brazil, from May to July 2006. Laboratorial analyses were carried out in the laboratories of Universidade Federal do CearÃ, Universidade de Fortaleza, Grupo Edson Queiroz and Instituto Centro de Ensino TecnolÃgico (CENTEC). The experiments aimed to assess the possibility of aggregating value to castor bean (Ricinus communis) plantations placing honey bee (Apis mellifera) colonies in the area. The following aspects were investigated: colony development in castor bean plantations; potential of castor bean plantations for honey production; possible toxicity of castor bean pollen and/or nectar to honey bees and humans; physical-chemical and organoleptic characteristics of castor bean honey and its commercial potential. Results showed that castor bean plantations offer good conditions for development of A. mellifera colonies because it provides pollen and nectar which are readily used by honey bees; castor bean showed to be an important nectar source for beekeeping leading in only 49 days to an average production between 18.82 (apiary in area of castor bean clean cultivation) and 23.52 kg (apiary in area of castor bean with wild weeds), similar to the annual national mean production; castor bean pollen and nectar are not toxic to honey bees or mammals, suggesting that, probably, are also adequate for human consumption. Castor bean honey presents physical-chemical characteristics within the Brazilian regulations for honey, and its organoleptic characteristics were well rated by population in test trials suggesting commercial potential. It was concluded that beekeeping in castor bean plantations can improve the area profitability, contribute to mitigate ecological impacts caused by agriculture, besides generating a natural, nutritive and well accepted product by the population.
7

O pontecial da mamoneira (Ricinus Communis L.) para a exploração apícola: produção, toxidez e qualidade de mel e pólen / The pontecial of mamoneira (Ricinus Communis L.) for holding apícola: production, toxidez and quality of honey and pólen.

Milfont, Marcelo de Oliveira January 2007 (has links)
MILFONT, Marcelo de Oliveira. O pontecial da mamoneira (Ricinus Communis L.) para a exploração apícola: produção, toxidez e qualidade de mel e pólen. 2007. 91 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Zootecnia, Fortaleza-CE, 2007 / Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-08-04T15:13:17Z No. of bitstreams: 1 2007_dis_momilfont.pdf: 738781 bytes, checksum: e58f207fefae85dec997524d68c2c300 (MD5) / Approved for entry into archive by Nádja Goes (nmoraissoares@gmail.com) on 2016-08-04T15:13:37Z (GMT) No. of bitstreams: 1 2007_dis_momilfont.pdf: 738781 bytes, checksum: e58f207fefae85dec997524d68c2c300 (MD5) / Made available in DSpace on 2016-08-04T15:13:37Z (GMT). No. of bitstreams: 1 2007_dis_momilfont.pdf: 738781 bytes, checksum: e58f207fefae85dec997524d68c2c300 (MD5) Previous issue date: 2007 / The research was carried out in the Núcleo de Produção Comunitária Santa Clara, belonging to the company Brasil Ecodiesel, in the county of Canto do Buriti, state of Piauí, Brazil, from May to July 2006. Laboratorial analyses were carried out in the laboratories of Universidade Federal do Ceará, Universidade de Fortaleza, Grupo Edson Queiroz and Instituto Centro de Ensino Tecnológico (CENTEC). The experiments aimed to assess the possibility of aggregating value to castor bean (Ricinus communis) plantations placing honey bee (Apis mellifera) colonies in the area. The following aspects were investigated: colony development in castor bean plantations; potential of castor bean plantations for honey production; possible toxicity of castor bean pollen and/or nectar to honey bees and humans; physical-chemical and organoleptic characteristics of castor bean honey and its commercial potential. Results showed that castor bean plantations offer good conditions for development of A. mellifera colonies because it provides pollen and nectar which are readily used by honey bees; castor bean showed to be an important nectar source for beekeeping leading in only 49 days to an average production between 18.82 (apiary in area of castor bean clean cultivation) and 23.52 kg (apiary in area of castor bean with wild weeds), similar to the annual national mean production; castor bean pollen and nectar are not toxic to honey bees or mammals, suggesting that, probably, are also adequate for human consumption. Castor bean honey presents physical-chemical characteristics within the Brazilian regulations for honey, and its organoleptic characteristics were well rated by population in test trials suggesting commercial potential. It was concluded that beekeeping in castor bean plantations can improve the area profitability, contribute to mitigate ecological impacts caused by agriculture, besides generating a natural, nutritive and well accepted product by the population. / A pesquisa de campo foi conduzida no Núcleo de Produção Comunitária Santa Clara, pertencente a empresa Brasil Ecodiesel, no município de Canto do Buriti – PI, entre maio e julho de 2006. As análises laboratoriais foram realizadas nos Laboratórios da Universidade Federal do Ceará, Universidade de Fortaleza, Grupo Edson Queiroz e Instituto Centro de Ensino Tecnológico (CENTEC) do Cariri. Os experimentos foram realizados com o objetivo de investigar a possibilidade de agregar valor a cultura da mamona (Ricinus communis) por meio da apicultura. Os seguintes aspectos foram investigados: desenvolvimento de colônias de Apis mellifera em meio a plantio de mamoneira; potencial da mamoneira para a produção de mel por abelhas A. mellifera; possível toxidez do pólen e/ou néctar da mamoneira para abelhas melíferas e humanos; características físico-químicas e organolépticas do mel de mamona e potencial comercial deste mel. Os resultados mostraram que a cultura da mamoneira oferece boas condições de desenvolvimento para colônias de A. mellifera uma vez que oferece pólen e néctar, e que estes são prontamente utilizados pelas abelhas; a mamoneira mostrou-se uma importante fonte de néctar para a exploração apícola, tendo sido produzido em apenas 49 dias medias entre 18,82 kg (apiário em área de cultivo limpo de mamona) e 23,52 kg (apiário em área de mamona com ervas silvestres) de mel, semelhantes à média anual do país. O pólen e o mel da mamoneira não são tóxicos para abelhas melíferas e para roedores, indicando que, provavelmente, seja próprio para o consumo humano. O mel da mamoneira apresenta características físico-químicas dentro da legislação brasileira e características organolépticas bem aceitas pela população, demonstrando que o mesmo possui potencial comercial. Conclui-se que a exploração apícola da cultura da mamona pode aumentar a rentabilidade das áreas de cultivo e minimizar os impactos ecológicos da agricultura, além de gerar um produto natural, nutritivo e bem aceito pela população em geral.

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