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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.
11

Biomineralization in cement based materials : inoculation of vegetative cells

Basaran, Zeynep 06 September 2013 (has links)
Recently, self-healing applications of cement-based materials have received a lot of interest. One major area of interest with respect to self-healing applications in cement-based systems focuses on using biomineralization processes. Biomineralization is biochemical process in which microorganisms stimulate the formation of minerals. The existing research on biomineralization in cement-based systems has showed promising results and the studies suggest that biomineralization could be a useful approach for remediation of cracks on the surface of concrete. This dissertation presents the results of an intensive study undertaken to understand the influence of vegetative bacteria, specifically Sporosarcina pasteurii (S. pasteurii), when it is incorporated within cement paste. Vegetative S. pasteurii cells were suspended in a urea-yeast extract medium and this medium was mixed with cement. The influence of the vegetative S. pasteurii cells on Portland cement paste properties, such as compressive strength, hydration kinetics, and setting time was evaluated. It was determined that the hydration kinetics was highly influenced when the bacterial medium was used to prepare cement paste, and severe retardation was observed. It was also observed that an increase in calcium carbonate precipitation, particularly calcite, occurred within cement paste when the bacterial medium was used. Furthermore, use of the bacterial medium resulted in reducing the porosity and increasing the compressive strength of the hardened paste. Ex-situ culture experiments were conducted to determine the impact of pH and calcium concentration on the morphology of calcium carbonate precipitate; the results indicated that the morphology of the precipitate was more influenced by calcium concentration. A key focus of this dissertation was to examine the viability of the vegetative cells that were inoculated in cement paste. Viable S. pasteurii cells were found to be present in hardened cement paste samples that were as old as 330-days, and 50% of the viable cells detected were defined as vegetative cells. At last, the use of including internal nutrient reservoirs as a means to extend the viability of the bacterial cells within hardened cement paste was explored. The results showed that the percentage of vegetative cells remaining was affected when internal nutrient reservoirs was incorporated into the system. / text
12

Sumedėjusių augalų vegetatyvinis dauginimas / Vegetative reproduction of woody plants

Žemgulytė, Vaida 02 September 2010 (has links)
Norint sėkmingai padauginti augalus gyvašakėmis, susiduriama su daugeliu problemų. Tačiau atlikus išsamią dauginamų augalų analizę galima gauti gerų vegetatyvinio dauginimo rezultatų. Vegetatyvinis augalų dauginimas yra aktualus dėl to, kad nesuteikia galimybių paveldimam kintamumui. Didelė ir reikšminga vegetatyvinio augalų dauginimo metodų įvairovė leidžia pasirinkti optimaliausią dauginimo būdą. Vegetatyviniu būdu dauginami augalai greičiau užima želdinamą teritoriją. Tai naudinga norint turėti daugiau tos pačios rūšies dauginamų augalų. Gyvašakių šaknydinimas lieka vienintelis dauginimo būdas sėklų neišauginantiems augalams, arba kai dauginimas sėklomis nepriimtinas dėl veislės skilimo. Daugelis dekoratyvinių augalų dauginami tik vegetatyviniu būdu. Šiuo būdu dauginti augalai išlaiko F1 kartos savybes. / To successfully multiply plants slips, we can face with many problems. However, after a detailed analysis of reproduction of these plants we can get good vegetative reproduction results. Vegetative reproduction of plants is relevant, because there is no opportunity for hereditary variability. A large and significant vegetative reproduction of plant diversity of approaches allows us to choose the optimum method of reproduction. Vegetative reproducted plants dominate the territory. It is useful if you want to have more of the same species reproducted plants. The naturalize by slips is the only way to seed multiplication not grown plants, or reproduction of seeds is unacceptable for a variety of degradation. Many decorative plants are reproducted only vegetative. This method keeps the plants F1-generation features.
13

Anatomia dos órgãos vegetativos de representantes brasileiros de Zygopetalinae (Orchidaceae) e sua relação com a taxonomia da subtribo /

Moraes, Cristiano Pedroso de. January 2011 (has links)
Resumo: As Orchidaceae, facilmente reconhecíveis pelo aspecto modificado de suas flores, compreendem mais de 20.000 espécies cosmopolitas distribuídas em cinco sub-famílias. A subtribo Zygopetalinae é um grupo tipicamente neotropical incluído na subfamília Epidendroideae e compreende cerca de 30 gêneros e 418 espécies de hábito vegetativo variado. Visando complementar as informações sobre a estrutura dos órgãos vegetativos dos representantes dessa subtribo, estudou-se a anatomia das raízes, caules e folhas de alguns táxons brasileiros, muitos deles de posição taxonômica incerta e pouco conhecidos, sob o ponto de vista anatômico. Comparando os resultados obtidos com os descritos para outros representantes da mesma subtribo, observou-se uma uniformidade anatômica entre os órgãos das espécies brasileiras e das anteriormente estudadas, corroborando a inclusão de Zygopetalinae na tribo monofilética Cymbidieae. Observou-se, também, uma uniformidade nas características anatômicas, dentro dos gêneros, indicando que muitos aspectos podem ser úteis na análise sistemática da subtribo / Abstract: The Orchidaceae, easily recognized by the modified aspect of their flowers, comprises more than 20,000 cosmopolitan species distributed in five subfamilies. The Zygopetalinae subtribe is a typically neotropical group included in the Epidendroideae subfamily and comprises around 30 genera and 418 species of varied vegetative habit. Aiming to complement the information about the structure of the vegetative organs of the representatives of this subtribe, the anatomy of roots, stems and leaves of some Brazilian taxa, may of them of uncertain and little known taxonomic position under the anatomical point of view, were studied. Comparing the results obtained with the ones described for the other representatives of the same subtribe, an anatomical uniformity among the organs of the Brazilian species and the ones previously studied was observed corroborating the inclusion of Zygopetalinae in the Cymbidieae monofiletic tribe. It was also observed an uniformity in the anatomical characteristics, within the genera, indicating that many aspects can be useful in the systematic analysis of the subtribe / Orientador: Maria das Graças Sajo / Coorientador: Fábio de Barros / Banca: Neuza Maria de Castro / Banca: Tatiane Maria Rodrigues / Banca: Adelita Aparecida Sartori Paoli / Banca: Sandra Maria Carmello Guerreiro / Doutor
14

A revision of the genus Centella L. (Apiaceae)

Schubert, Mahalia Theresia Reina 02 June 2014 (has links)
D.Phil. (Botany) / A taxonomic revision of the genus Centella is presented that is based on vegetative and reproductive characters. Genetic data was included in the extensive research ofpossible hybridisation. Hybridization as a possible mechanism of evolution may account for the lack of conguence between taxonomic characters in Centella. Phylogenetic and phenetic methods of analysis were used to explore the relationships among species. The results show that Centella is a particularly difficult genus, with many ofthe problems experienced at species level being a reflection ofthe problematic nature of the Apiaceae. The taxonomic treatment includes nomenclature, synonymy, typification, diagnostic characters, detailed illustrations and geographical distribution of all 45 species that are recognized. Keys to the subgenera, sections and species are provided. The revision includes several taxonomic and nomenclatural changes. The genus is subdivided as follows: Subgenus Trisanthus Subgenus Solandra Subgenus Centella 1 species 4 species Section Erianthae Section Tri/obae Section Centella Section Virgatae 9 species 3 species 16 species 12 species The following 13 new species were described: C. annua, C. calcaria, C. rotundifolia, C. umbellata, C. ternata, C. crenata, C. cryptocarpa, C. gymnocarpa, C. pi/osa, C. brachycarpa, C. dolichocarpa, C. thesioides and C. glauca. One ofthese species C. cryptocarpa, has been collected for the first time. Centalla rotundifolia, C. cordata and C. longifolia were elevated to species rank and C. rigescens was reinstated as a species of Centella. The number of varieties was significantly reduced and variation within the species is mostly described informally. Varieties were retained for only two species. New varieties are: C. tridentata var. tridentata, C. tridentata var. littoralis, C. tridentata var. hermanniifolia, C. tridentata var. dregeana, C. graminifolia var. graminifolia, C.graminifolia var. natalensis and C. graminifolia var. stipitata.
15

A reverse genetics approach to investigate the role of CRY1 and CRY2 in mediating floral initiation in the long day plant nicotiana sylvestries and the short day plant N. tabacum CV. Maryland Mammoth

Yendrek, Craig R. 13 September 2006 (has links)
No description available.
16

Regulated Expression Of OsMADS1, A MADS Domain Containing Transcription Factor, Involved In Rice Floret Development

Kartha, Reena V 03 1900 (has links) (PDF)
No description available.
17

Vegetative propagation of honeybush (Cyclopia subternata) from stem cuttings.

Mabizela, Gugu Shila January 2014 (has links)
M. Tech. Horticulture / Honeybush tea is the herbal tea made from the leaves, stems and flowers of Cyclopia spp., indigenous to the Eastern and Western Cape Provinces of South Africa. Due to the health benefits of honeybush, the demand for this tea has increased worldwide. To meet the demand, it is required to cultivate honeybush as a commercial crop. The shortage of plant material and variation in the quality of honeybush has prompted the need to propagate plants vegetatively through rooted cuttings in order to improve the planting material by achieving homogeneity, and to meet the demand and thus relieve pressure on wild populations. A study was conducted to evaluate the vegetative propagation of honeybush (Cyclopia subternata) from stem cuttings to optimize the adventitious rooting protocols.
18

Análise espectral de variedades de Vitis vinifera a partir de dados radiométricos de dossel em vinhedos de Pinto Bandeira, RS / Spectral analysis of varieties of vitis vinifera from canopy radiometric data vineyards of Pinto Bandeira, RS

Bombassaro, Magno Gonzatti January 2016 (has links)
A crescente demanda do mercado mundial em aumentar a produção agrícola e minimizar danos ambientais confere crescente relevância à agricultura de precisão, para a qual a Geoinformação é uma importante ferramenta. Diferentes dados provenientes de imagem de sensores orbitais e terrestres têm sido utilizados para o monitoramento agrícola em escalas local, regional e global. Neste contexto, e focalizando esta percepção à viticultura, o objetivo deste estudo é avaliar o comportamento espectral de diferentes cultivares de videiras ao longo do ciclo fenológico, dando suporte para realização da discriminação espectral das variedades e o mapeamento da variação espacial do vigor vegetativo dentro da parcela. Para o desenvolvimento da pesquisa proposta o trabalho foi dividido em duas etapas. A primeira investigação consistiu em um estudo realizado em vinhedos da região de Borgonha na França, onde foram estudadas as variedades de uva Chardonnay e Pinot Noir. O trabalho teve como pressuposto verificar se as categorias de qualidade que definem os vinhedos e são transmitidas a partir do solo ao vinho são igualmente transmitidas às folhas das videiras, e se estas podem ser detectadas na informação espectral de imagens de satélites ASTER. Os resultados obtidos mostraram ser possível esta discriminação e instigaram novos estudos mais detalhados que foram conduzidos em vinhedos da Vinícola Geisse, localizada na Serra Gaúcha, realizados a partir de dados de radiometria de campo e imagens orbitais. Novamente foram investigadas as variedades viníferas Chardonnay e Pinot Noir, monitoradas ao longo de duas safras. As medições de campo foram realizadas com um radiômetro FieldSpec Pro. Também foram usados dados orbitais provenientes do sensor WorldView-2. Dados de campo e orbitais apresentaram relações consistentes, e mostraram ser possível discriminar as variedades através de suas características espectrais. A alta relação sinal/ruído dos dados de campo permitiu detectar diferenças consistentes e sistemáticas nos comprimentos de onda do verde e vermelho, atribuídas à presença de pigmentos como as antocianinas. O monitoramento da dinâmica espectral do ciclo fenológico revelou feições espectrais consistentes nos comprimentos de onda do infravermelho atribuídas ao período de senescência da videira. A espacialização dos dados de vigor vegetativo, obtidos através de índices de vegetação (NDVI) permitiu a setorização de áreas com diferentes potenciais enológicos. / The growing demand of world markets to increase agricultural production and to minimize environmental impacts puts the Geoinformation as an important tool of precision agriculture. Several sets of data of images from orbital and ground sensors have been used for agricultural monitoring at local, regional and global scales. In this context, focusing this perception to viticulture, the aim of this study was to evaluate the spectral comportment of different grapevine cultivars along of phenological cycle, giving support to realization of spectral discrimination of varieties and the mapping of the spatial variation of vegetative vigor within the plot. For the development of this project, our research was divided into two stages. The first research consisted in a study of vineyards of the Burgundy region in France, where the studied grape varieties were Chardonnay and Pinot Noir. The work was to verify the assumption that the quality categories that define the vineyards and are transmitted from the soil to wine are also transmitted to the leaves of the vines, and these can be detected in the spectral information contained in ASTER satellite images. Results showed that this discrimination is indeed possible, and lead to the second part of the project, with new and more detailed studies, which were performed in the vineyards of Geisse Winery, located in the Serra Gaúcha region, Brazil, based on field radiometry and orbital images. The same grape varieties Chardonnay and Pinot Noir grapes were again investigated. Field measurements were performed with a radiometer FieldSpec Pro. The investigation was made on two vine plots, based on a selection of plants of the Chardonnay and Pinot Noir, which were monitored over two growing seasons. Orbital data were from the WorldView-2 sensor. Field and orbital data showed consistent relations and showed that it is possible to distinguish the varieties by their spectral characteristics. The high relation signal/noise of field data allowed detecting consistent and systematic spectral features at red and green wavelengths, thought to be linked to the presence of pigments such as anthocyanins. The monitoring of spectral dynamics during the phenological cycle revealed consistent spectral features in infrared wavelengths assigned to the vine senescence period. The spatial distribution of vegetative vigor data obtained from the vegetation index (NDVI) allowed the sectorization of areas with different enological potentials.
19

Anatomia dos órgãos vegetativos de representantes brasileiros de Zygopetalinae (Orchidaceae) e sua relação com a taxonomia da subtribo

Moraes, Cristiano Pedroso de [UNESP] 15 February 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-15Bitstream added on 2014-06-13T21:01:39Z : No. of bitstreams: 1 moraes_cp_dr_rcla.pdf: 1437388 bytes, checksum: e066c411adea82f23bca10e7e585f5c6 (MD5) / As Orchidaceae, facilmente reconhecíveis pelo aspecto modificado de suas flores, compreendem mais de 20.000 espécies cosmopolitas distribuídas em cinco sub-famílias. A subtribo Zygopetalinae é um grupo tipicamente neotropical incluído na subfamília Epidendroideae e compreende cerca de 30 gêneros e 418 espécies de hábito vegetativo variado. Visando complementar as informações sobre a estrutura dos órgãos vegetativos dos representantes dessa subtribo, estudou-se a anatomia das raízes, caules e folhas de alguns táxons brasileiros, muitos deles de posição taxonômica incerta e pouco conhecidos, sob o ponto de vista anatômico. Comparando os resultados obtidos com os descritos para outros representantes da mesma subtribo, observou-se uma uniformidade anatômica entre os órgãos das espécies brasileiras e das anteriormente estudadas, corroborando a inclusão de Zygopetalinae na tribo monofilética Cymbidieae. Observou-se, também, uma uniformidade nas características anatômicas, dentro dos gêneros, indicando que muitos aspectos podem ser úteis na análise sistemática da subtribo / The Orchidaceae, easily recognized by the modified aspect of their flowers, comprises more than 20,000 cosmopolitan species distributed in five subfamilies. The Zygopetalinae subtribe is a typically neotropical group included in the Epidendroideae subfamily and comprises around 30 genera and 418 species of varied vegetative habit. Aiming to complement the information about the structure of the vegetative organs of the representatives of this subtribe, the anatomy of roots, stems and leaves of some Brazilian taxa, may of them of uncertain and little known taxonomic position under the anatomical point of view, were studied. Comparing the results obtained with the ones described for the other representatives of the same subtribe, an anatomical uniformity among the organs of the Brazilian species and the ones previously studied was observed corroborating the inclusion of Zygopetalinae in the Cymbidieae monofiletic tribe. It was also observed an uniformity in the anatomical characteristics, within the genera, indicating that many aspects can be useful in the systematic analysis of the subtribe
20

Comparative Vegetative Anatomy Of The Tribe Triticeae Dumortier (poaceae) In Turkey

Mavi, Dudu Ozlem 01 September 2012 (has links) (PDF)
Triticeae Dumort. is a tribe within the Pooideae subfamily of Poaceae. Major crop genera found in this tribe include barley (Hordeum), wheat (Triticum) and rye (Secale) all of which are closely related to each other. In Turkey, with the several subgroups, this tribe is represented by 16 genera and 75 species, many of which have great economic values. The main objective of this research work is to determine the taxa of this tribe on the basis of their diagnostic anatomical characters of vegetative organs for the recognision of genera, sections, species, and infraspecific categories. By using both fresh and herbarium specimens, transverse sections of vegetative organs were obtained by using two different sectioning methods. This study covers both qualitative anatomical characters, such as sclerenchyma position, hair density and intercellular cavities of roots, shapes of leaves, presence of midrib, occurrence of leaf hairs, shapes of girders or strands, arrangement of sclerenchyma around vascular bundles and arrangement of epidermal cells, cell wall undulations, appearance of silica bodies, type of bulliform cells, arrangement of culm vascular bundles and their connections to the epidermis, hollowness of culms, as well as quantitative characters, such as sclerenchyma line number of roots, vascular bundle line numbers and diameters of culms, sclerenchyma line number of leaf margins, line numbers and sizes of all types of costal leaf hairs, stomata and interstomatal cell lines. In conclusion, all these properties are useful to understand both systematics and evolutionary relationships of the taxa. Moreover, the leaves of the tribe have the most numerous diagnostic characters. The roots do not have central metaxylem. The metaxylem elements are scattered in the vascular cylinder. The internodular parts of the culms may be hollowed or solid. However, the nodular parts of the culms generally have the same structure. Furthermore, there are two species which can be assigned as a subtribe.

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