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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

Disglass — el vidrio como material estructurante del mobiliario en Chile

Maass Aguilera, Flavia January 2009 (has links)
No description available.
82

Veranderinge in vrye en gebonde aminosuurkonsentrasies in verouderende angelierkroonblare

Van der Westhuizen, Abraham Jozua 25 September 2014 (has links)
M.Sc. (Botany) / Please refer to full text to view abstract
83

An economic analysis of production and trade of selected ornamental nursery stock in British Columbia

Stodola, Bernard James January 1976 (has links)
The primary purpose of this thesis was to examine short run supply aspects of British Columbian (EB.CC..)) ornamental nursery stock propagation and trade. To this end, spatial equilibrium analysis was utilized in studying the influences of Canadian plant protection regulations, transportation costs, and costs of production on United States (U.S.) import levels into the province as well as domestic production levels. ;The basic constructs of the spatial equilibrium analysis were the transportation model and the production-distribution model. These models were used in establishing interregional and international production and trade patterns with respect to B.C. They relate to selected ornamental varieties under specified efficiency criteria and various parameters, with reference to the 1973 calendar year. In addition, sensitivity analysis was conducted within the spatial equilibrium framework. This indicated the strength of the competitive position of domestic propagators vis-a-vis U.S. propagators and provided an insight into the future state of health of the B.C. industry. Finally, an examination of domestic propagation levels was undertaken via quantitative and qualitative analyses in an attempt to explain the residual U.S. import quantities into B.C. For the purpose of this study eight distinct geographical regions were identified. Each region contained a representative point of origin or destination. Seven of these regions were specified as production or supply regions, comprised of four domestic production regions and three U.S. production regions. Five of the eight regions were identified as consumption or demand regions, comprised of four B.C. consumption regions and one Prairie consumption region. Three nursery conifers, Juniperus chinensis 'Pfitzeriana Aurea, ' Thuja occidentalis Pyrdmidalis' and Pinus mugho mughus were selected as being representative ornamental plant materials for the purpose of this study. The results of this study show that in 1973, B.C. propagators of the specified nursery materials had a competitive advantage in supplying domestic consumption regions. But this competitive advantage was reduced to some extent by the existence of Canadian plant protection regulations. This had the effect of both directly and indirectly inducing movement of materials from the U.S. in greater quantities than would have been the case without regulations. This study further shows that the competitive advantage of domestic propagators over U.S. growers was tenuous. Assuming 1975 transportation rates, a 10 percent increase in domestic costs of production, and constant U.S. procurement costs, would lead to the competitive advantage being shifted to U.S. suppliers for some ornamental materials. In addition the study discovers nothing to indicate that domestic propagation levels were unduly constrained by resource limitations. The results suggest that rapid domestic consumption increases coupled with grower uncertainty regarding legislative constraints and certain 'externalities' enjoyed by U.S. propagators, accounted for greater import levels than would have been expected a priori. It is believed that the findings of this analysis can be extended to other ornamental plant materials involved in B.C. propagation, insofar as they are produced and sold in part or entirely under similar conditions to those dealt with in the study. / Land and Food Systems, Faculty of / Graduate
84

Effects of trinexapac-ethyl on ornamental grass species

May, Alvin Scott 07 August 2010 (has links)
Studies were conducted to evaluate the effects of trinexapac-ethyl (TE) on height reduction, tillering, chlorophyll content, color, flowering, and root development of three ornamental grasses: Calamagrostis ×acutiflora 'Karl Foerster', Miscanthus sinensis 'Variegatus', and Pennisetum ×advena 'Rubrum'. Two applications of TE reduced height in all grasses and improved chlorophyll content in C. 'Karl Foerster' while delaying flowering in M. 'Variegatus' and P. 'Rubrum'. Tillering was slightly increased in M. 'Variegatus' with two TE applications. Shoot dry weight (SDW) and root dry weight (RDW) were reduced in C. 'Karl Foerster', SDW was reduced in P. 'Rubrum' and SDW and RDW were unaffected by applications of TE in M. 'Variegatus'. TE is effective for growth control in ornamental grass production systems; however, the results are species specific and should be tested further before widespread use on other ornamental grass species.
85

Controlling Growth in Echinacea Hybrids

Grossman, Mara Celeste 02 May 2017 (has links)
New hybrid Echinacea cultivars, based on crosses of Echinacea purpurea (L.) Moench with several other Echinacea species, have generated interest and excitement in the marketplace due to novel flower colors and forms. However, these cultivars vary significantly in their growth habits and requirements from the species. We examined factors in the production of Echinacea hybrid cultivars to provide guidance to growers. Foliar sprays 600 mg·L⁻¹ benzyladenine (BA) increased numbers of branches between 19% and 83% in Echinacea cultivars while 400 mg·L⁻¹ dikegulac sodium or 500 mg·L⁻¹ ethephon did not improve branching. Of several height control PGRs applied to E. ‘Marmalade,’ only plants treated with two applications of 5000 mg·L⁻¹ daminozide were shorter (24%) compared to untreated controls although flowering was also reduced by 70%. Echinacea ‘Harvest Moon’ plants were shorter in response to all of the PGRs applied, with the best results seen in plants treated with foliar sprays of uniconazole (one application of 30 mg·L⁻¹ or two applications of 15 mg·L⁻¹ ), two applications of 5000 mg·L⁻¹ daminozide, or 4 mg·L⁻¹ paclobutrazol applied once as a drench. Supplying N at 150 mg·L -1 during the growing season provided Echinacea cultivars adequate nutrition and maximized numbers of branches and flowers and shoot dry weight. In overwintering, fertilization treatments that resulted in low substrate electrical conductivity going into dormancy, 5.0 kg·m controlled release fertilizer 15N-3.9P-10K or 150 mg·L⁻¹ N using 15N-2.2P-12.5K applied using constant liquid feed, resulted in the highest survival rates of Echinacea cultivars. As a monitoring tool, SPAD measurements were not successful in predicting tissue N levels in Echinacea hybrids. Twenty-one hybrid cultivars acquired as stage 3 tissue culture plantlets were grown under one of three photoperiods (10-hour, 16-hour, or 24-hour) for 10 weeks before being transplanted to larger containers and grown under natural daylength until flowering. Providing Echinacea hybrid cultivars with a 16-hour photoperiod during liner production resulted in plants which flowered soonest without negative effects on growth. The need for height control PGRs varied by cultivar; however, overall height control PGRs controlled flower stalk height and increased market rating. / Ph. D.
86

Ecology and niche characterization of the invasive ornamental grass Miscanthus sinensis

Dougherty, Ryan Fitzgerald 12 June 2013 (has links)
The recent trend in bioenergy feedstock development focuses on the use of large-statured perennial grasses that pose a relatively high risk of becoming invasive species due to the similarity in desirable agronomic traits with those of many of our worst invaders. Thus, it would be prudent to evaluate the potential ecological benefits and consequences of widespread cultivation of potentially invasive species. Miscanthus sinensis and its sterile daughter species, Miscanthus × giganteus, are two prominent bioenergy feedstock candidates due to their low input requirements and significant biomass production in a broad range of growing conditions. Despite being an extremely popular ornamental grass, and naturalizing in over half of US states, little is actually known about the biology, ecology and niche requirements of M. sinensis. Thus, the objective of our research is to characterize extant M. sinensis populations, and evaluate the niche requirements, especially in terms of the commonly limiting resources of light and soil moisture. In order to better assess the risk of M. sinensis (and subsequently M. × giganteus) cultivation, we surveyed 18 naturalized populations across the east coast to characterize habitat preferences, population structure, and plant performance across a latitudinal gradient. We found the vast majority of M. sinensis populations occurred in areas of high and low resource availability (e.g. soil nutrients and light) along roadsides and forest edges, with outlier individuals found in forest understories. We conducted a greenhouse study to compare shade and soil moisture tolerance among common ornamental cultivars and naturalized populations, where we found enhanced plant growth and vigor in naturalized biotypes compared to ornamentals across varying levels of shade. We also found that both naturalized and ornamental biotypes were not significantly affected by soil moisture stress, and thus express significant drought tolerance. Finally, we investigated the temperature and moisture requirements of M. sinensis seeds and determined a base temperature of approximately 8"C, as well as variable moisture and time to germination requirements between varieties and seed sources. These basic ecological studies will help refine and support future evaluations and weed risk assessments of both Miscanthus sinensis and M. × giganteus, which is critical in prevention of major ecological invasions. / Master of Science in Life Sciences
87

Ornamental Plants Impact Insect Pollinator Abundance and Diversity in Gardens

Palmersheim, Michala Christine 02 February 2022 (has links)
As pollinator populations decline globally, public interest in creating pollinator gardens to help sustain bee abundance and diversity is rising, and there are many lists of recommended pollinator plantings and suggestions for bee-friendly flowers. However, these suggestions often lack grounding in empirical data. While anecdotal and expert suggestions are not without merit, it is crucial that we have clear, replicable, evidence-based planting recommendations to help boost the abundance and diversity of pollinators that will visit the plants. To fill this gap, we created a pollinator garden containing 25 pollinator plantings, some on previous recommendation lists, some not, and that were either native or non-native and perennial or annual. We surveyed the number and taxonomy of pollinator visitors to these plants through non-destructive methods. These data were analyzed to determine which plants are most effective at attracting abundant and diverse flower-visiting insects. We analyzed preference between native and non-native plants, perennials and annuals, and among different plant species. Our data revealed significant variation in the total abundance and diversity of flower-visiting attracted insects among plant species. Brown-eyed Susans attracted the highest abundance of insect visitors (average number of visitors per day = 53) and were 26-fold more attractive than Begonias, which attracted the lowest abundance of insect visitors (average number of visitors per day = 2). Lavender attracted the highest diversity of insect visitors (Simpson's Reciprocal Diversity Score: 3.5) compared to Pineapple Sage (Simpson's Reciprocal Diversity Score: 1.6), which attracted the lowest diversity of insect visitors. Additionally, we found that native perennials significantly attracted the greatest abundance of visitors compared to either non-native annuals or non-native perennials (p < 0.001). We conclude that ornamental landscape plants can support an abundance and diversity of pollinator visitors, and planting schemes should take into consideration the effects of plant species, plant lifespan, and plant origin. We can use these data to better inform the regional community how to attract and support abundant and diverse pollinator populations within urban and sub-urban ornamental landscape gardens. / Master of Science in Life Sciences / Many people want to build gardens with flowers that are attractive to pollinators, which can be bees, flies, butterflies, moths, and other insects. How, though, do we know what should be planted in that garden? Anyone with access to a computer can find lists of recommended plants for a pollinator garden, and they are provided by a variety of sources. However, the plants included on these lists are often not the same. Some lists may claim a handful of plants are the most attractive to pollinators, while another list will suggest different plants as the most attractive. In addition, these lists often are not based on scientific evidence. Our goal was to use these recommendations to build a pollinator garden so that we can collect data on the plants and determine which plants are best in our garden at attracting insect pollinators. We created a pollinator garden that includes 25 of popular landscape plants, many of which are found on lists of current plant recommendation lists. Then we let the plants grow and bloom, and during the summer, we counted and identified the different species of insects found on each plant. We then ranked plants, from best to worst, at their ability to attract insects and pollinators in numbers and in diversity. Additionally, we found that insects are generally more likely to visit plants that are native to the region. Using this information, we can share our results with the public so that anyone can build their own pollinator garden that will be the most attractive to pollinators.
88

Caracterização de áreas favoráveis à extração de blocos graníticos de grade porte com o uso da eletrorresistividade, Cabo de Santo Agostinho, PE / not available

Silva, Diego Daniel 24 October 2014 (has links)
Os métodos geoelétricos, principalmente a eletrorresistividade, estão sendo cada vez mais requisitados na área da mineração, indicando espessura de capeamento de solo, zonas fraturadas e heterogeneidades do material, viabilizando economicamente, ou não, um projeto minerário. Este trabalho, realizado no município do Cabo de Santo Agostinho -PE, apresenta e discute resultados de aplicações do método geofísico, da eletrorresistividade, como instrumento de auxílio na abertura de uma nova frente de lavra para extração de blocos graníticos de grande porte. Foi investigada a espessura do capeamento de solo, bem como as principais zonas locais de falhas e fraturas. Para isso foram realizadas 32 SEVs (03 SEVs por perfil, à exceção da Linha 11, com 02) com arranjo Schlumberger de AB/2 máximo de 60metros, e 11 caminhamentos elétricos com arranjo dipolo-dipolo de AB=MN=20 metros,com aproximadamente 1000m de extensão cada perfil. As SEVs foram dispostas nas linhas de modo a cobrir adequadamente a área do terreno, possibilitando a confecção de um mapa de contorno da profundidade do topo rochoso e a caracterização do perfil de alteração pedológico. Os caminhamentos elétricos foram dispostos paralelamente entre si e espaçados de 60 metros, podendo ser observadas as possíveis configurações do topo rochoso, como rocha não fraturada e zonas fraturadas. A partir dos dados dos caminhamentos elétricos foram elaboradas simulações 3D de resistividade e para a estimativa de volume de rocha não fraturada na área de estudo (com base nas resistividades mais elevadas).Os resultados obtidos mostraram a eficiência da eletrorresistividade na determinação do topo da rocha sã e detecção das zonas fraturadas no maciço granítico. / The geoeletric methods, especially electroresistivity, are being progressively more required on mining, for identifying soil thickness, fractured zones and geological heterogeneities, to check economical viability of mining projects. This work, held in Cabo de Santo Agostinho-PE city, presents and discusses geophysics application results of electroresistivity as a tool for helping the opening of a new granitic blocks exploitation front. The soil thickness was investigated, as well as the main local fault zones and fractures. A total of 32 VESs (03 VESs per section, exception made to line 11, with 02 VESs) using Schlumberger array with AB/2 maximum of 60 m, and 11 geoelectrical profilings using dipole-dipole array (AB=MN=20 m), with section lengths close to 1000 m. The VESs lines were organized in order to cover the studied area properly, allowing mapping the top of the rock massif and characterizing the soil profile. The geoelectrical profilings were disposed parallel with 60 m gap among each other, enabling the observation of the massif top configurations, such as fractured and non fractured zones. 3D resistivity simulations were performed using the geoelectrical profilings data in order to estimate the total volume of non fractured rock in the studied area (based on the highest resistivities). The obtained data showed the efficiency of electroresistivity for fractured zones detection and for mapping the top of the fresh rock massif.
89

CURVAS DE CRESCIMENTO MORFOMÉTRICO DE GUPPY (Poecilia reticulata) DO NASCIMENTO À MATURIDADE SEXUAL.

Paiva, Sérgio Côrtes 07 February 2012 (has links)
Made available in DSpace on 2016-08-10T10:31:03Z (GMT). No. of bitstreams: 1 SERGIO CORTES PAIVA.pdf: 795523 bytes, checksum: 516cf579af289fb7d528d54feea3847d (MD5) Previous issue date: 2012-02-07 / The ornamental aquaculture in the world is an activity of economic and social importance since it can be conducted under family, generating income and serving as an option to keep the population in the rural areas. The cultivation of ornamental fish is considered one of the most profitable sectors of Brazilian fish. The Guppy is an omnivore and teleost ornamental fish originating in Central America. This is one of the best-selling fish in the world followed by Kinguios. One of the characteristics of the Guppy sexual dimorphism is present. The Guppies born with about 6mm long. There are several factors that affect the growth rate of fish, such as temperature, pH, ammonia levels, dissolved oxygen in water, power, density, and genetics. This work aims to establish morphometric growth curves based on age for the Guppy, using - if different nonlinear models. The study was conducted in the Research Lab and Production of Aquatic Organisms (LAPO), located at Campus II of the Pontifical Catholic University of Goiás (PUC - GO) in the period from February 11 to June 21, 2011. We used 128 fish species Poecilia reticulata. Were made during the trial period 64 randomized trials, with a total of 128 fish Guppy, and 2 individuals / sample of each box. For morphometric measurements were made of the head length (CCAB), standard length (CP), Height (AND) and width (NLD). For each measure and reason morphometric growth curves were estimated using the roles of Von Bertalanffy, Richards, Brody, Gompertz and Logistics. The correlation between standard length, head length, width and height taken on the dorsal fin is high and Meaningful. The models of Gompertz, Brody and Bertalanffy were the ones that best described the growth of morphometric Guppies. / A aquicultura ornamental no mundo é uma atividade de importância econômica e social uma vez que pode ser conduzida em regime familiar, gerando renda e servindo como opção para manter a população rural no campo. O cultivo de peixes ornamentais é considerado hoje um dos setores mais lucrativos da piscicultura brasileira. O Guppy é um peixe ornamental teleósteo e onívoro originário da América Central. Este é um dos peixes mais vendidos no mundo seguido pelos kinguios. Uma das características do Guppy é apresentar dimorfismo sexual. Os Guppys nascem com aproximadamente 6mm de comprimento. Existem vários fatores que interferem na taxa de crescimento de peixes, tais como temperatura, pH, níveis de amônia, oxigênio dissolvido na água , alimentação, densidade e genética. O presente trabalho tem o objetivo de estabelecer curvas de crescimento morfométrico em função da idade para o Guppy, utilizando - se diferentes modelos não lineares. O estudo foi realizado no Laboratório de Pesquisa e Produção de Organismos Aquáticos (LAPOA), localizado no Campus II da Pontifícia Católica de Goiás (PUC GO), no período de 11 de fevereiro a 21 de junho de 2011. Foram utilizados 128 peixes da espécie Poecilia reticulata. Foram realizados durante o período experimental 64 amostragens aleatórias, com o total de 128 peixes Guppy, sendo 2 indivíduos/ amostragem de cada caixa. Para a avaliação morfométrica foram feitos medidas do comprimento da cabeça (CCAB), comprimento padrão (CP), Altura (AND) e Largura (LND). Para cada medida e razão morfométrica foram estimadas curvas de crescimento utilizando-se as funções de Von Bertalanffy, Richards, Brody, Gompertz e Logística. A correlação entre Comprimento Padrão, Comprimento da Cabeça, Largura e Altura tomadas à frente da nadadeira dorsal são altas e significativas. Os modelos de Gompertz, Brody e Bertalanffy foram os que melhor descreveram o crescimento morfométrico dos Guppies.
90

Análise prospectiva para o setor atacadista de flores e plantas ornamentais no Brasil e suas tecnologias da informação e comunicação

Torres, Daniel Felipe Uribe January 2015 (has links)
O agronegócio das Flores e Plantas Ornamentais (FPO) no Brasil movimenta mais de R$ 5 bilhões ao ano com uma taxa de crescimento anual entre o 8% e 16%, gerando mais de 206.000 empregos diretos. Em 2012, a balança comercial da floricultura brasileira mostrou saldo negativo de US$ 13,468 milhões, devido ao incremento em suas importações por parte de seus maiores concorrentes do grupo MERCOSUL, Equador e Colômbia. A falta de implementação de sistemas de informação e as deficiências do controle nos gargalos de todos os processos, fazem que a maioria das perdas que se produz no elo atacadista sejam originadas da falta de cuidados no transporte, a não conservação da cadeia de frio e as demoras logísticas. Este trabalho tem como objetivo lançar um olhar prospectivo nesse complexo. A prospecção do futuro sempre foi e será apreciada pelos tomadores de decisões. Ao longo das últimas décadas, organizações internacionais, governos, empresas e organizações não governamentais têm realizado estudos sobre panoramas futuros, com o objetivo de ganhar tempo em preparar-se para superar seus concorrentes e ser competitivos em cada área de atuação. Por meio de uma revisão bibliográfica atual, focada na análise de toda a cadeia de suprimento de FPO, somado a uma serie de entrevistas com experts da floricultura nacional e internacional, analisaram-se atividades e ferramentas tecnológicas usadas em cada um dos processos envolvidos no atacado, como as condições do transporte, planejamento das entregas e os registros dos controles que garantem a qualidade do produto final. Com esse aporte construíram-se quatro possíveis cenários futuros para o setor atacadista de FPO brasileiro, baseados na utilização e implementação da Tecnologia de Informação. (1) Cenário Lirio, que apresenta a situação em que as CEASAS serão os maiores aglomerados do negócio de FPO sempre, enquanto eles realizarem uma reestruturação do complexo físico, assim com um plano de capacitação para o pessoal encarregado de manipular e ofertar as FPO. (2) Cenário Tulipa, que propõe um agrupamento por parte dos atacadistas com maior representatividade, com o fim de gerar e compartilhar informações sobre tendências, safras e formação de preços. (3) Cenário Girassol, que sugere que seja analisado o futuro dos métodos de compra de FPO por parte do consumidor final, para assim entender as diferentes ferramentas e estratégias de mercado que devem ser usadas pelas empresas atacadista para conservar e atrair novos clientes. (4) Cenário Agapantho, que mostra como a situação atual em relação a investimento e adoção de Tecnologia (TIC) do setor não muda, o que acarretaria uma série de consequências para o mercado interno e externo, facilitando ainda mais o ingresso de concorrentes internacionais ao Brasil. / Agribusiness of Flowers and Ornamental Plants (FPO) in Brazil handles more than $ 5 billion a year with an annual growth rate between 8% and 16%, generating more than 206,000 direct jobs. In 2012, the trade balance of the Brazilian floriculture showed a deficit of US $ 13.468 million, due to the increase in its imports by their larger competitors MERCOSUR group, Ecuador and Colombia. The lack of implementation of information systems and control deficiencies in bottlenecks of the process, make the most of the loss that occurs in the wholesale link to originate from a lack of care during transport, the failure to keep the cold chain and logistical delays. This paper aims to launch a prospective look at this complex. The prospect of the future has always been and will be greatly appreciated by decision makers. Over the past decades, international organizations, governments, companies and nongovernmental organizations have conducted studies on future panoramas, in order to gain time to prepare to overcome your competitors and be competitive in each area. Through a current literature review focused on the analysis of the entire FPO supply chain, plus a series of interviews with experts of national and international floriculture, analyzed activities and technological tools used in each of the processes involved in wholesale such as transport conditions, planning of deliveries and the records of the controls that guarantee the quality of the final product. With this supply were built four possible future scenarios for the wholesale sector of Brazilian FPO, based on the use and implementation of Information Technology. (1) Lirio Scenario, which shows the situation where the WM will be the largest OPF business of always crowded, as they carry out a restructuring of the physical complex, so with a training plan for staff handling and offer the FPO. (2) Scenario Tulip, which proposes a grouping by wholesalers with greater representation in order to generate and share information on trends, harvests and pricing. (3) Scenario Sunflower, which suggests it is analyzed the future of OPF purchase methods by the final consumer, so as to understand the different tools and market strategies that should be used by wholesale companies to retain and attract new customers. (4) Agapantho scenario that shows how the current situation in relation to investment and adoption of technology (ICT) in full sector does not change, what would entail a number of consequences for the domestic and foreign markets, further facilitating the entry international competitors to Brazil.

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