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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.
21

Growth of Clonal Red Maples on Varying Site Conditions in Mississippi and Response to Pneumatic Fracturing and Liquid Injection

Fulgham, David Tildon 03 May 2019 (has links)
Trunk height, diameter, and stomatal conductance measurements were taken over a three-year time frame on clonal red maple cultivars [Acer rubrum ‘Frank Jr’] on two sites with varying conditions. Physiological and morphological effects on tree growth were measured on both sites in response to Pneumatic Fracturing (PF) and Liquid Injection (LI) treatments. The primary questions asked in study one were: (1) Does stomatal conductance differ among the two sites during mid-summer? and (2) Do height and diameter measures differ among the two sites? In study two, I asked: (1) Do height, diameter and stomatal conductance differ between site modification treatments within each site? Control samples on the Site 2 had significantly more growth than the controls on the Site 1. PF and LI treatments showed significantly more diameter growth on the Site 1 while a significant difference was also seen in stomatal conductance following treatments on Site 1.
22

The Behavioral Dynamics of Shooter Bias in Virtual Reality: The Role of Race, Armed Status, and Distance on Threat Perception and Shooting Dynamics

Eiler, Brian A. January 2017 (has links)
No description available.
23

Microarray Analysis of Differential Expression of Genes in Shoot Apex and Young Leaf of English Ivy (<i>Hedera helix</i> L. cv. Goldheart)

Shin, Seung-Geuk 15 July 2010 (has links)
No description available.
24

Analýza Individuální herní činnosti jednotlivce u mladších žáků / Analysis of an individual playing perfomance for younger pupils

Frolík, Lukáš January 2016 (has links)
Name: Analysis of an individual playing perfomance for younger pupils Objective: The aim of this study is to determine the technical level of the younger pupils AC Sparta Praha and SK Slavia Praha against Bohemans 1905. It is specifically the percentage success collecting of the ball, pass and shot. Further, as I will be interested in the failing collecting, shooting and passing the ball skills. Methods: The method that I used for processing work is called indirect observation of previously recorded video. Data were processed mainly quantitative method. Results: Using the results, we found that a skill that is among hard according to the literature, and handling of the ball had the highest success rate of all monitored. Furthermore, what I found is that the players have many more attempts each game activities played under pressure than no pressure on the players. Keywords: Football, pass, shoot, ball collecting
25

Aspectos relacionados à competência organogenética de meristemas caulinares de Dendrobium Second Love (Orchidaceae) / Aspects of Dendrobium second love shoot meristems (Orchidaceae) related to organogenetic competence

Cruz, Aline Bertinatto 11 August 2009 (has links)
O emprego da cultura de tecidos, órgãos ou plantas In vitro tem sido largamente utilizado como técnica de micropropagação com finalidade de estudar os vários fatores envolvidos no crescimento e desenvolvimento vegetal. O objetivo do presente trabalho foi estudar as condições fisiológicas relacionadas a diferentes respostas organogenéticas de natureza vegetativa e reprodutiva em plantas de Dendrobium Second Love (Orchidaceae) cultivadas in vitro. Foi possível analisar através da técnica de micropropagação de incubação de tais plantas no escuro as variações no potencial organogenético de seus segmentos caulinares apical e subapical em formar explantes para a regeneração de novas plantas in vitro e as decorrente variações morfológicas das plantas assim regeneradas. A referida técnica foi também empregada com a incubação dessas plantas no claro para gerar material suficiente ao estudo do envolvimento do TDZ, Z, ZR, iP, iPR na indução de seu brotamento e de sua floração. Foi possível assim a análise das variações tanto dos teores endógenos de açúcares solúveis quanto de etileno decorrentes da aplicação dessas citocininas, bem como aferir a influência da duração do tratamento e da idade da planta. Os resultados mostraram que a idade de incubação das plantas no escuro e no claro é importante não apenas para gerar novas plantas como também para induzir o seu brotamento e o florescimento. Sucessivas etapas de padronização evidenciaram que a causa principal da variação no potencial organogenético dos explantes utilizados derivou da região de origem da planta estiolada, bem como da idade do próprio tecido, sendo que um menor tempo de incubação no escuro levou a um aumento na porcentagem de regeneração das plantas, da mesma forma que um menor período de escuro tornou as plantas mais homogêneas em relação ao tamanho. Dentre as condições estudadas, todas as citocininas induziram brotamento, porém em relação ao florescimento apenas o TDZ mostrou-se eficaz. Pôde-se ainda verificar que um período de exposição de 10 dias no TDZ induziu as plantas à floração. Os níveis de açúcares solúveis dos brotos submetidos aos tratamentos com Z, ZR, iP, iPR e TDZ mostrou-se mais elevado naqueles tratados com TDZ sugerindo uma maior utilização de açúcares nas plantas induzidas a floração. Em relação ao acúmulo de etileno dentro dos frascos verificou-se, por fim, que as plantas tratadas com TDZ induziram maior acúmulo de etileno em relação às plantas controle. / In vitro tissues, organs or plants culture has been widely used as a micropropagation technique aiming to study a number of factors involved in vegetable growth and development. In the present study, we evaluated the physiological conditions related to different vegetative or reproductive organogenetic responses in in vitro Dendrobium Second Love (Orchidaceae) plants. We evaluated the organogenetic potential of the shoot segments in inducing explants for the regeneration of new in vitro plants and their morphological changes. This technique was also micropropagated with light incubation of the plants in order to provide enough material for the study of the participation of TDZ, Z, ZR, iP, iPR in the induction of their budding and its flowering. Thus, it was possible to analyze the endogenous levels of soluble sugars, ethylene concentration, following the application of these cytokinins, as well as evaluated the effect of treatment duration and the plant age. The results showed that the plant incubation age is not only important to generate new plants, but also to induce its budding and flowering, irrespective of the dark/light condition. Successives tests showed that the main reason for changes in the organogenetic potential of the explants was due to the etiolated plant region, as well the tissue age. In this sense, lower dark incubation length led to an increase in the percentage of plants regeneration, and to more homogeneous plant sizes. Among the studied conditions, all cytokinins induced budding, however concerning flowering only TDZ was effective. It was also verified that a 10-day exposure to TDZ can induce plants to flowering. The level of soluble sugars in the buds submitted to the treatment with Z, ZR, iP, iPR and TDZ was higher in the ones treated with TDZ, suggesting a higher sugar use in the plants induced flowering. Regarding the ethylene accumulation in the flasks, it was observed that plants treated with TDZ induced higher ethylene accumulation when compared to control plants.
26

PropagaÃÃo in vitro de Moringa oleifera L. / Propagation in vitro of moringa oleifera l.

JÃnior RÃgis Batista Cysne 25 August 2006 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / A moringa, Moringa oleifera L., Ã uma Ãrvore da famÃlia Moringaceae, destacando-se pelo uso intensivo das propriedades quÃmicas de suas sementes. O presente trabalho objetivou estabelecer um protocolo bÃsico para a micropropagaÃÃo da moringa. Os Ãpices caulinares utilizados na micropropagaÃÃo foram retirados de plÃntulas germinadas in vitro cultivadas em meio MS. Ãpices caulinares de plantas adultas tambÃm foram isolados e cultivados em meio WPM. A desinfestaÃÃo das sementes e dos Ãpices caulinares de plantas adultas foi realizada com diferentes concentraÃÃes de hipoclorito de sÃdio (NaOCl) sendo que a 0,25 % por 10 minutos, proporcionou os melhores resultados para o estabelecimento das culturas. Os Ãpices caulinares, excisados de plantas cultivadas em meio MS apÃs, 12 dias da germinaÃÃo, foram submetidos a diferentes combinaÃÃes de 6-benzilaminopurina (BAP) (0,0; 0,05; 0,25; 1,25 e 6,25 &#956;M). No meio com 1,25 &#956;M de BAP verificou-se uma taxa de multiplicaÃÃo de 8,9. A fim de maximizar a regeneraÃÃo de plantas in vitro, foram realizados experimentos para avaliar as concentraÃÃes de BAP e de Ãcido indol-3-butÃrico (AIB) no meio de cultivo com diferentes concentraÃÃes e combinaÃÃes. A melhor taxa de regeneraÃÃo e alongamento de brotaÃÃes foi obtida com o meio MS contendo 0,25 &#956;M de BAP e 0,25 &#956;M de AIB. Contudo apÃs o subcultivo neste mesmo meio, observou-se uma reduÃÃo na taxa de multiplicaÃÃo de 8,95 para 5,08. Para os Ãpices provindos de plantas adultas foi realizado um ensaio testandose diferentes meios de cultura. O meio com os sais WPM promoveu um melhor estabelecimento para os Ãpices, visto que os mesmos se apresentavam menos vitrificados se comparados aos demais meios. Definido o meio WPM realizou-se um ensaio com diferentes combinaÃÃes de BAP (0,0; 0,05; 0,25; 1,25 e 6,25 &#956;M). O meio com 6,25 &#956;M promoveu a formaÃÃo de calo seguida da formaÃÃo de brotaÃÃes. Estas foram subcultivadas em meio contendo 0,25 &#956;M de BAP onde se desenvolveram sem a formaÃÃo de brotaÃÃes laterais. / Moringa Moringa oleifera Lam is a tree plant belonging to the family Moringaceae widely used for the chemical properties its seeds. In this work, we attempted to develop a basic protocol for the micropropagation of the plant. Shoot apexes originating from in vitro germinated seedlings on Murashige and Skoog (MS) medium were used as primary explants. Adventitious shoots obtained from field growing trees were also isolated and inoculated on Wood Plant Medium (WPM) for the same purpose. Subjecting the seeds to various regimes and sequences of surface sterilization using sodium hypochlorite (NaOCl) showed that the best regime is the use of 0.25% NaOCl for 10 minutes. In an attempt to micropropagate Moringa, excised adventitious shoots were cultured on MS medium for 12 days, following which they were transferred to MS medium supplemented with varying concentrations (0.0,0.05,1.25 and 6.25uM) of 6-Benzylaminopurine (BAP). Explants subjected to the medium containing 1.25uM BAP demonstrated the highest rate of multiplication of 89%. In order to optimize the regeneration of plants from the primary explants, they were subjected to combinations of BAP and Indol-3-butyric acid at various concentrations. Although the highest rate of regeneration and shoot elongation was obtained when equimolar concentrations of BAP and IBA of 0.25uM was supplemented in an MS medium, there was a sharp decrease in the rate of multiplication from 89.5% to 50.8% when the shoots were sub cultured onto the same medium after 28 days. Subjecting shoot apexes obtained from field growing plants to WPM and MS based medium formulations, it was discovered that WPM promoted better proliferation of the explant compared to all other medium. Using WPM supplemented with different concentrations of BAP (0.0,0.05,0.25,1.25), the medium containing 6.25uM BAP was found to result in formation of callus followed by shoot formation. Transferring the proliferating shoots to a medium containing 0.25uM BAP led to their development without formation of adventitious shoots.
27

Effects of environment and genetics on western pine shoot borer, Eucosma sonomana, infestation levels in ponderosa pine plantations of central Oregon /

Prueitt, Sara C. January 1997 (has links)
Thesis (M.S.)--Oregon State University, 1998. / Typescript (photocopy). Includes bibliographical references (leaves 40-43). Also available on the World Wide Web.
28

Aspectos relacionados à competência organogenética de meristemas caulinares de Dendrobium Second Love (Orchidaceae) / Aspects of Dendrobium second love shoot meristems (Orchidaceae) related to organogenetic competence

Aline Bertinatto Cruz 11 August 2009 (has links)
O emprego da cultura de tecidos, órgãos ou plantas In vitro tem sido largamente utilizado como técnica de micropropagação com finalidade de estudar os vários fatores envolvidos no crescimento e desenvolvimento vegetal. O objetivo do presente trabalho foi estudar as condições fisiológicas relacionadas a diferentes respostas organogenéticas de natureza vegetativa e reprodutiva em plantas de Dendrobium Second Love (Orchidaceae) cultivadas in vitro. Foi possível analisar através da técnica de micropropagação de incubação de tais plantas no escuro as variações no potencial organogenético de seus segmentos caulinares apical e subapical em formar explantes para a regeneração de novas plantas in vitro e as decorrente variações morfológicas das plantas assim regeneradas. A referida técnica foi também empregada com a incubação dessas plantas no claro para gerar material suficiente ao estudo do envolvimento do TDZ, Z, ZR, iP, iPR na indução de seu brotamento e de sua floração. Foi possível assim a análise das variações tanto dos teores endógenos de açúcares solúveis quanto de etileno decorrentes da aplicação dessas citocininas, bem como aferir a influência da duração do tratamento e da idade da planta. Os resultados mostraram que a idade de incubação das plantas no escuro e no claro é importante não apenas para gerar novas plantas como também para induzir o seu brotamento e o florescimento. Sucessivas etapas de padronização evidenciaram que a causa principal da variação no potencial organogenético dos explantes utilizados derivou da região de origem da planta estiolada, bem como da idade do próprio tecido, sendo que um menor tempo de incubação no escuro levou a um aumento na porcentagem de regeneração das plantas, da mesma forma que um menor período de escuro tornou as plantas mais homogêneas em relação ao tamanho. Dentre as condições estudadas, todas as citocininas induziram brotamento, porém em relação ao florescimento apenas o TDZ mostrou-se eficaz. Pôde-se ainda verificar que um período de exposição de 10 dias no TDZ induziu as plantas à floração. Os níveis de açúcares solúveis dos brotos submetidos aos tratamentos com Z, ZR, iP, iPR e TDZ mostrou-se mais elevado naqueles tratados com TDZ sugerindo uma maior utilização de açúcares nas plantas induzidas a floração. Em relação ao acúmulo de etileno dentro dos frascos verificou-se, por fim, que as plantas tratadas com TDZ induziram maior acúmulo de etileno em relação às plantas controle. / In vitro tissues, organs or plants culture has been widely used as a micropropagation technique aiming to study a number of factors involved in vegetable growth and development. In the present study, we evaluated the physiological conditions related to different vegetative or reproductive organogenetic responses in in vitro Dendrobium Second Love (Orchidaceae) plants. We evaluated the organogenetic potential of the shoot segments in inducing explants for the regeneration of new in vitro plants and their morphological changes. This technique was also micropropagated with light incubation of the plants in order to provide enough material for the study of the participation of TDZ, Z, ZR, iP, iPR in the induction of their budding and its flowering. Thus, it was possible to analyze the endogenous levels of soluble sugars, ethylene concentration, following the application of these cytokinins, as well as evaluated the effect of treatment duration and the plant age. The results showed that the plant incubation age is not only important to generate new plants, but also to induce its budding and flowering, irrespective of the dark/light condition. Successives tests showed that the main reason for changes in the organogenetic potential of the explants was due to the etiolated plant region, as well the tissue age. In this sense, lower dark incubation length led to an increase in the percentage of plants regeneration, and to more homogeneous plant sizes. Among the studied conditions, all cytokinins induced budding, however concerning flowering only TDZ was effective. It was also verified that a 10-day exposure to TDZ can induce plants to flowering. The level of soluble sugars in the buds submitted to the treatment with Z, ZR, iP, iPR and TDZ was higher in the ones treated with TDZ, suggesting a higher sugar use in the plants induced flowering. Regarding the ethylene accumulation in the flasks, it was observed that plants treated with TDZ induced higher ethylene accumulation when compared to control plants.
29

Weed management in sugar cane : critical periods of weed competition and mechanisms of interference from Paspalum paniculatum and P. urvillei

Seeruttun, Sumantlall 10 June 2009 (has links)
The aim of this project was to provide sound scientific underpinning for the development of new weed management strategies in sugar cane by exploring competition from the major weeds, and explaining the different mechanisms of weed interference from Paspalum paniculatum and P. urvillei. Critical periods of weed control (CPWC) were studied in six field trials. In ratoon cane, CPWC with natural weed infestations started between 228 and 916 growing degree days (GDD), and ended between 648 and 1311 GDD, depending on the site and cane variety. These results represented a maximum CPWC of 12 to 28 weeks after harvest (WAH). In plant cane, the CPWC started earlier (6 WAP) and was longer than those in ratoon cane. Relative competitiveness ‘q’ values of eight common weed species showed that sugar cane was a stronger competitor than most of the weeds tested. The adverse effect of weed competition in sugar cane is not experienced before several weeks following weed emergence. Weeds transplanted 10 WAP caused no significant change in cane yield response as compared to those transplanted 4 WAP. Paspalum paniculatum was often found to be more competitive than P. urvillei, although the latter produced more leaf area and grew taller to intercept more light within the canopy. This indicated that other mechanisms of weed interference were involved and competition for light was more important during the earlier (tillering) growth stages. Root competition was shown to be as important as shoot competition. Root competition effects were observed several weeks after imposing competition, suggesting that it was more important than competition for light in the post-tillering phase. Application of root exudates from the two grasses to sugar cane confirmed an allelopathic effect on the root biomass of sugar cane. One chemical identified in the leachates from both Paspalum species for the allelopathic effects was 2-propenoic acid, 3-(4-methoxyphenyl). The main implications of the above findings for the Mauritian sugar industry would involve a change in the timing of application of herbicides. A new tank-mix consisting of trifloxysulfuron + ametryn and amicarbazone has been found to meet this objective. This strategy will enable a saving of at least one herbicide treatment per season. / Thesis (PhD)--University of Pretoria, 2011. / Plant Production and Soil Science / unrestricted
30

Invading Monotypic Stands of Phalaris Arundinacea: A Test of Fire, Herbicide, and Woody and Herbaceous Native Plant Groups

Foster, Richard D., Wetzel, Paul R. 01 June 2005 (has links)
Phalaris arundinacea L. is an aggressive species that can dominate wetlands by producing monotypic stands that suppress native vegetation. In this study invasion windows were created for native species in monotypic stands of P. arundinacea with either fire or herbicide. Three native species groups, herbaceous plants, herbaceous seeds, and woody shrubs, were planted into plots burned or treated with herbicide in the early spring. Fire did not create an effective invasion window for native species; there was no difference in P. arundinacea root and shoot biomass or cover between burned and control plots (p ≥ 0.998). Herbicide treatment created an invasion window for native species by reducing P. arundinacea root and shoot biomass for two growing seasons, but that invasion window was fast closing by the end of the second growing season because P. arundinacea shoot biomass had nearly reached the shoot biomass levels in the control plots (p = 0.053). Transplant mortality, frost, and animal herbivory prevented the herbaceous species and woody seedlings from becoming fully established in the plots treated with herbicide during the first year of the experiment. Transplanted monocots had a greater survival than dicots. By the second growing season the herbaceous group had the greatest mean areal cover (5%), compared to the woody seedlings (3%) and seed group (0%). Long-term monitoring of the plots will determine whether the herbaceous transplants will compete effectively with P. arundinacea and whether the woody species will survive, shade the P. arundinacea, and accelerate forest succession.

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