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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.
121

Barns tankar om växande och icke-växande : Semi-strukturerade intervjuer med förskolebarn för att synliggöra vad de tänkte om det som växer och vad som behövs för att växa. / Children’s thoughts about growing and non-growing : Semi-structured interviews with preschool children in order to make their thoughts about what grows and what is needed to create growth visible

Storm, Angelica January 2016 (has links)
This thesis is about children´s thoughts on what is capable of growth and what does not, as well as what is needed for these things to grow. My survey has been carried out in three different preschools with children who are four and five years old. My purpose is to create more knowledge about children's perceptions of what differentiates growing from not growing. My aspiration is to make it visible what the children's thoughts is about what it means that something is growing and about what is needed for anything to grow, in order to provide preschool teachers with an increased understanding of the thoughts and experiences children may have. In my research I have used semi-structured interviews. During the interviews I showed the children a toy-car, seeds, leaves, twigs, balloons, rocks, ants and pictures of fire, the sun and the earth. My interview questions emanated from these things. The children used their previous experience and past knowledge to determine if these things were growing or not, this led to the fact that their opinions often parted. The children agreed with each other that humans, seeds, leaf and twigs could grow. They explained that they had memories of themselves as shorter before and that they had also planted seeds. The children also agreed upon that the earth and toy car wasn’t able to grow. None of the children had seen a toy car or the earth growing and they explained it by saying these objects were unable to. When it came to the sun, fire, ants, rocks and balloons they had different experiences and therefore different opinions. One child remembered a large rock which it had climbed upon and draws the conclusions that it must have grown. Another child had observed the sun as bigger in the sky and therefore thought the sun could grow. To have awareness of what knowledge children already have and in which ways children can interpret their own knowledge is important for preschool teachers in order to be able to meet children where they are and help them gain greater knowledge and understanding in the area. / Det här examensarbetet handlar om barns tankar om vad som växer och vad som inte växer samt vad som behövs för att något ska växa. Min undersökning har utförts på tre olika förskolor med barn som är fyra och fem år gamla. Mitt syfte är att skapa mer kunskap om barns uppfattningar kring vad som skiljer det som växer från det som inte växer. Mitt mål är att med denna studie  kunna synliggöra barnens tankar om vad det innebär att något växer och vad som behövs för att något ska kunna växa för att ge förskollärare ökad förståelse för vilka tankar och erfarenheter barnen kan ha med sig. I min undersökning har jag använt semi-strukturerade intervjuer. Vid intervjutillfället hade jag med mig en leksaksbil, frön, blad, kvistar, ballonger, stenar, myror och bilder på eld, solen och jorden och mina intervjufrågor utgick ifrån dessa. Barnen använde sina tidigare erfarenheter och kunskaper för att bestämma om någonting växte eller inte, detta medförde att deras åsikter oftast gick isär. Barnen var överrens om att de själva, frön, blad och kvistar kunde växa. De berättade att de hade minnen av att de själva varit kortare förut och de hade även planterat frön. Barnen var också överrens om att jorden och leksaksbilen inter kunde växa. Inget barn hade sett en leksaksbil eller jorden växa och detta förklarade de genom att svara att de inte kunde växa. När det kom till solen, eld, myror, stenar och ballonger så hade barnen olika erfarenheter och därför också olika åsikter. Ett barn mindes en stor sten som barnet klättrat på, och drog slutsatsen att den stenen måste ha växt. Ett annat barn hade sett solen se stor ut på himlen och ansåg därför att solen kunde växa. Att ha kännedom om vilka kunskaper barnen har med sig och hur barnen kan tolka dessa kunskaper är viktigt när förskollärare ska möta barnen där de är och hjälpa dem att få ökad kunskap och förståelse på området.
122

Growing neural gas for intelligent robot vision with range imaging camera

Sasaki, Hironobu, Fukuda, Toshio, Satomi, Masashi, Kubota, Naoyuki 09 August 2009 (has links)
No description available.
123

The effect of physical and hydraulic properties of peat moss and pumice on Douglas-fir bark based soil-less substrates /

Zazirska Gabriel, Magdalena. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaves 48-50). Also available on the World Wide Web.
124

Ecology of Fungus-Farming by Termites : Fungal Population Genetics and Defensive Mechanism of Termites against the Parasitic Fungus Pseudoxylaria

Katariya, Lakshya January 2017 (has links) (PDF)
All living organisms require food for growth and survival. Heterotrophs depend on autotrophs such as green plants which can synthesize their own food unlike heterotrophic animals. Among heterotrophs, only humans and some insects have the remarkable ability to cultivate crops for food. While humans cultivate plants, three insect lineages—ants, termites, and beetles—cultivate fungi inside their nests in obligate mutualistic exo-symbioses. Interestingly, just like human agriculture, insect fungus farms are also threatened by weeds and pests, e.g. the farms of fungus-growing termites which cultivate Termitomyces fungi can be overgrown by weeds such as the parasitic fungus Pseudoxylaria. Studies on ant and beetle fungus-farming systems have uncovered the important role of chemicals and behaviour in helping these insects to protect their crops from parasitic fungi. On the other hand, studies on the termite system till now, have only revealed the presence of antifungal compounds and actinobacteria which are largely non-specific and inhibitory to the mutualistic crop fungi. Antifungal behavioural mechanisms, if present, are yet to be discovered. Therefore, this thesis focuses on different anti-Pseudoxylaria mechanisms employed by fungus-growing termites, viz. role of nest abiotic factors, mechanism of fungal recognition by termite hosts, behavioural response of termite to Pseudoxylaria presence and coupling of this behaviour to anti-Pseudoxylaria activity. The present thesis has been divided into six chapters. CHAPTER 1 gives a brief literature review on fungus-farming insects and the different mechanisms which insects employ in order to keep their fungal farms safe from growth of parasitic fungi with specific reference to fungus-growing termites. The obligate mutualistic interaction between termites and the Termitomyces fungus is 19–49 My-old and is, therefore, a very ancient agriculture system. The mutualistic fungus is cultivated on partially digested plant matter called fungus comb inside the nest and harvested by termites for nutrition. At the same time, the weedy fungal parasite Pseudoxylaria can compete with the mutualistic fungus for nutrition leading to negative effects on the fungal farms. Termite hosts are believed to use abiotic factors, antibiotics and hygienic behaviours to keep their fungal gardens free from parasitic fungi such as Pseudoxylaria. However, the actual mechanisms used by termites against parasitic fungi are unclear. Unravelling the proximate mechanisms used in fungal cultivar protection is central to understanding the evolutionary stability of these farming mutualisms. CHAPTER 2 examines the diversity and population genetic structure of Termitomyces and Pseudoxylaria strains associated with the fungus-growing termite Odontotermes obesus. Genetic diversity of cultivar and parasite could have important implications for the stability of the mutualistic interaction, e.g. genetic clonality arising from monoculture is generally thought to make populations more prone to infection by parasites. Using molecular phylogenetic tools, within-nest genetic homogeneity was found in Termitomyces species but not in Pseudoxylaria species. Lower OTU but higher genotypic diversity (within the most abundant OTU) was found in the genus Termitomyces compared to Pseudoxylaria. Additionally, population genetics methods suggested a sexual population structure for Termitomyces and clonal propagation for Pseudoxylaria species. This is the first study to investigate the population genetics of the symbiotic fungi associated with the termite genus Odontotermes or any other termite species from India. In CHAPTER 3, the effect of nest micro-environment alone on the growth of the parasitic fungus Pseudoxylaria was examined. For this, seasonal changes in nest xiii temperature and CO2 were recorded and in situ and ex situ growth experiments were performed on Pseudoxylaria. The monthly pattern of mound temperatures was found to be similar to the outside—cycling from highs in summer to lows in winter—but characterised by dampened variation compared to high daily fluctuations outside. Moreover, the mound CO2 levels were found to be orders of magnitude above atmospheric levels and, unlike the outside, were characterised by daily and monthly fluctuations. With in situ experiments during summer and winter, the effect of these dissimilar conditions—inside and outside mounds—was examined on Pseudoxylaria growth. The growth of the parasite was found to be greater inside than outside the mound. Following this, the growth of different parasite isolates under controlled ex situ conditions was examined—spanning the variation in environmental conditions that mounds exhibit daily and seasonally. High CO2 levels decreased parasitic fungal growth in general but temperature had an isolate-dependent effect. Taken together, these results suggested that the parasite is adapted to survive in the mound. However, mound environmental conditions still seemed to exert a negative effect on parasite growth, even if they cannot inhibit Pseudoxylaria completely. These results shed light on the possible new role of termite-engineered structures in impacting parasitic fungus ecology, independent of any direct role of termites in suppressing parasite growth. This is the first study to investigate the effect of abiotic factors on Pseudoxylaria growth. In CHAPTER 4, whether termites can differentiate between Termitomyces and Pseudoxylaria was investigated. In a novel, laboratory-based choice assay, termites displayed a differential response towards the two fungi by burying the Pseudoxylaria with agar. Also, termites were found to be able to differentiate between the fungi using olfactory cues, i.e. smell, alone, for this task. The mutualistic and parasitic fungi were found to emit unique volatile bouquets which could help termites to distinguish between them. This is important because, whether termites use antifungal compounds or hygienic behaviours, it is crucial that they are able to differentiate between the parasitic and mutualistic fungi so that they can selectively use antifungal mechanisms—whether chemical or behavioural—against Pseudoxylaria. This is of special significance because, many actinobacteria and anti-Pseudoxylaria compounds isolated from this system till now, lack specificity and inhibit the mutualistic Termitomyces as well. Also, fungal grooming and weeding behaviours as displayed by fungus-growing ants have not yet been reported in termites. This is the first study to show that termites have the behavioural capacity to differentiate between the mutualistic and parasitic fungi in an ecologically relevant setting. In CHAPTER 5, whether the burying of Pseudoxylaria could affect its growth was investigated. It was found that termites can utilise agar, glass beads and soil for deposition over the offered fungal plugs but the use of agar and glass beads did not inhibit Pseudoxylaria growth effectively. On the other hand, soil deposition was found to decrease growth of both Pseudoxylaria and Termitomyces fungi post-burial. However, Pseudoxylaria was found to be affected more strongly than Termitomyces. Further, hypoxia acting alone seemed to decrease only Pseudoxylaria survival without any apparent effect on Termitomyces. Therefore, hypoxia induced by soil deposition may be the reason behind the decrease in Pseudoxylaria survival. However, presence of antifungal compounds can not be ruled out and they may be selectively applied in larger quantities on Pseudoxylaria with soil deposition. This study demonstrates an anti-Pseudoxylaria activity of this insect behaviour, unique to termites among fungus-farming insects, to the presence of the parasitic fungus. CHAPTER 6 concludes the findings of this thesis and suggests a working model for the mechanism of growth suppression of Pseudoxylaria inside a termite nest. In particular, focus is on the important role of abiotic factors when combined with termite behaviour in the apparent absence of Pseudoxylaria from termite nests. These results not only shed new light on how the ecology of these fungi is affected by their termite host but also reveal the mechanistic bases that may contribute fundamentally to the evolutionary stability of this ancient mutualism.
125

Megalomania in Dubai? : Assessing a Large-scale Public Entrepreneurship

Sagerklint, Sinsupa, Porntepcharoen, Patima January 2009 (has links)
No description available.
126

EFFECT OF LITTER TYPE ON GROWTH AND NUTRIENT CONTENT OF PERENNIAL GRASSES.

NGETHE, JOHN CHEGE. January 1984 (has links)
Biomass, cover, density, height and concentrations of N, P, C, Fe, Mn, Cu and Zn were evaluated in Sporobolus cryptandrus and Eragrostis lehmanniana at flowering and at seed ripening stage to determine whether these attributes are affected by the type of litter used or by litter treatment. Annual rye, California poppy and rye-poppy mixture were the sources of litter while litter treatments included removing organic residue, leaving organic residue standing or roto-tilling organic residue into the surface soil. The effect of litter type and litter treatment on the soil was evaluated. A parallel greenhouse experiment was carried out. Results indicate that California poppy contained a higher level of all nutrients studied compared to annual rye and contained about twice the concentrations of N, Mn, Zn and Fe. For both annuals and perennials, the nutrient content generally decreased between flowering and seed ripening with annuals indicating more decline than perennial grasses. The greatest decline was observed for N in California poppy. Field observation confirmed that the non-lignified California poppy shoots broke down faster than culms of annual rye. Biomass production in Sporobolus and Eragrostis was unaffected by litter type. However, for both species the highest biomass was obtained in the tilled treatment. Litter tilling produced more vigorous and healthier plants compared to other treatments. Except for P, nutrient concentrations were largely unaffected by litter type. The highest P concentrations were consistently obtained from perennial plants grown in annual rye plots. Fe and Cu concentrations were consistently higher in the tilled treatment. C and P appeared unaffected by litter treatment. N, Mn and Zn concentrations were more variable and more difficult to categorize. In soil samples, all nutrient concentrations were higher at the end of the study than at the beginning. Litter source appeared to have minimum effect on nutrient concentration while tilled treatment was superior to standing which was superior to the removed treatment.
127

CLINOPTILOLITE ZEOLITE: EFFECT ON AMMONIUM EXCHANGE REACTIONS, NITRIFICATION AND PLANT NITROGEN-USE EFFICIENCY.

Ferguson, Gregory Alexander January 1984 (has links)
Clinoptilolite zeolite has a theoretical cation exchange capacity of 2.25 moles of charge kg⁻¹, and a rigid three-dimensional lattice riddled with angstrom-sized tunnels, and interconnected voids, in which water and exchangable cations are held. The hypothesis was that clinoptilolite had the facility to preferentially and internally sorb NH₄⁺, where it would be physically protected from microbial nitrification. Hence nitrification rates would be decreased and plant N-fertilizer use efficiency increased. Exchange capacities of clinoptilolite determined at 30°C by saturation/desorption for NH₄⁺, K⁺ and Na⁺ were approximately 2.00 moles of charge kg⁻¹, while capacities for Ca²⁺ and Mg²⁺ were 1.53 and 0.97 respectively. On this basis three site groups were identified: those accessible to all cations studied, sites accessible to all cations but Mg²⁺ and sites only accessible to NH₄⁺, K⁺ and Na⁺. Equilibrium isotherms were used to determine selectivity of site groups at 30°C. Consideration of site accessibilities and selectivities indicate an overall preference of clinoptilolite of: K⁺ > NH₄⁺ > Na⁺ = Ca²⁺ > Mg²⁺. Notably, the plant macronutrient cations, K⁺ and NH₄⁺, are preferentially sorbed. Nitrification of NH₄⁺ on clinoptilolite amended sands incubated at 20% volumetric moisture capacities, was studied in the laboratory. Treatments were washed mortar sand amended with 0, 5 and 10% clinoptilolite by volume and 2.38 and 3.57 moles of NH₄⁺ m⁻³ of sand-clinoptilolite mix. Nitrification was evaluated by monitoring NH₄⁺ loss. Rates of nitrification decreased with increasing clinoptilolite amendment and decreased with N-fertilizer initially applied. The effect of clinoptilolite in slowing nitrification was more pronounced at higher initial NH₄⁺-fertilizer application. The hypothesis that internally sorbed NH₄⁺ in clinoptilolite is physically protected from microbes resulting in decreased nitrification rates was confirmed. The effect of clinoptilolite on N-use efficiency of creeping bentgrass was studied in a field trial. Factorial treatments included washed mortar sand amended with 0, 5 and 10% clinoptilolite by volume and 25, 50 and 75 kg of N ha⁻¹ growing month⁻¹. Approximately 45% of applied N was harvested in clippings from 10% clinoptilolite amended sand in contrast to 36% N recovery on 100 % sand. This supports the hypothesis of improved plant N-fertilizer use efficiency on clinoptilolite amended sand.
128

On the Determination of Building Footprints from LIDAR Data

George, Henry C. 15 December 2007 (has links)
A new approach to improve the determination of building boundaries through automatic processing of light detection and ranging (LIDAR) data is presented. The LIDAR data is processed and interpolated into a grayscale image of intensity values corresponding to height measurements. Ground measurements are separated from non-ground measurements by using a progressive morphological filter. With these measurements now distinct, further separation of non-ground measurements into building and non-building measurements is performed by growing regions with similar characteristics. These building areas are then refined, resulting in a ground plan representation of building boundaries, known as building footprints. Several algorithms are then implemented to clean these footprints. A new method is developed to analyze actual known satellite imagery in order to confirm identified building footprints.
129

Adaptabilidade e estabilidade de clones de cana-de-açúcar no Estado de São Paulo /

Fernandes Júnior, Antonio Ribeiro. January 2013 (has links)
Orientador: Joao Antonio da Costa Andrade / Coorientador: Pedro César dos Santos / Banca: Antonio César Bolonhezi / Banca: Hermann Paulo Hoffmann / Resumo: A interação genótipos com ambientes (GxA) representa uma das principais dificuldades para a seleção nos programas de melhoramento genético de qualquer espécie, seja na fase de seleção ou na recomendação de cultivares, onde os pesquisadores buscam alternativas para minimizar seus efeitos. Entre as alternativas está a escolha de cultivares com ampla adaptação e boa estabilidade. Os resultados de vários ambientes podem ser sintetizados por estudos de adaptabilidade e estabilidade fenotípica, permitindo conhecer melhor a capacidade produtiva e adaptação frente às variações ambientais de novos genótipos. O objetivo deste trabalho foi verificar a adaptabilidade e estabilidade de clones de cana-de- açúcar, além da estabilidade dos ambientes, quanto à produtividade em toneladas de colmos por ha (TCH) e toneladas de pol por ha (TPH) no Estado de São Paulo. Foram avaliados 10 clones e duas testemunhas comerciais de maturação média- tardia em primeira soca em 10 experimentos colhidos em agosto de 2008, utilizando o método de regressão bissegmentada e o método AMMI (Additive Main Effects and Multiplicative Interaction Analysis). A interação GxA para o caráter Pol%cana (PC) não foi significativa e TCH e TPH foram altamente correlacionados (r=0,97), apresentando resultados similares para todas as análises realizadas. Por isso, apenas os resultados de TCH foram apresentados e discutidos. Os resultados dos dois métodos foram comparados e evidenciaram que os clones RB975201, RB975157, RB975932, RB975242 e RB975162 são os mais promissores devido à produtividade acima das testemunhas, a alta estabilidade verificada em um ou nos dois métodos e adaptabilidade ampla ou específica. Os ambientes Tarumã, Guariba e Piracicaba, foram os mais estáveis, podendo servir de referência para recomendações em outras áreas / Abstract: The genotype x environment interaction (GE) is one of the main difficulties for selection in breeding programs of any species, either at the stage of selection or recommendation of cultivars, where researchers seek alternatives to minimize their effects. Between the alternatives is the choice of cultivars with wide adaptability and good stability. The results of various environments can be synthesized by studies of phenotypic adaptability and stability allowing better understand the production capacity and adaptation to environmental variations ahead of new genotypes. The objective of this study was to verify the adaptability and stability of sugar cane clones, in addition the stability of environments, for productivity in tons of cane per hectare (TCH) and tons pol per hectare (TPH) in São Paulo State, Brazil. Were evaluated 10 clones and two commercial checks of medium-late maturation in first-ratoon of experiments harvested in August 2008, utilizing bissegmented regression method and analysis AMMI (Additive Main Effects and Multiplicative Interaction Analysis). The interaction for the character Pol%cane (PC) was not significant and TCH and TPH were highly correlated (r = 0.97), with similar results for all analyzes. Therefore, only the results of TCH were presented and discussed. The results of two methods were compared and evidenced that clones RB975201, RB975157, RB975932, RB975242 and RB975162 are the most promising due to yield above checks, high stability observed in one or both methods and broad or specific adaptability. The environments Tarumã, Guariba and Piracicaba, are the most stable and may use as reference for recommendations in other areas / Mestre
130

O lazer e sua articulação com a educação: concepções de alunos e professores de um curso de extensão universitária sobre educação e envelhecimento / Leiusure and its articulation with the education: students and professors conception in a college course about growing old and education

Araújo, Mônica Ferreira de 10 April 2008 (has links)
Made available in DSpace on 2016-04-27T14:32:12Z (GMT). No. of bitstreams: 1 Monica Ferreira de Araujo.pdf: 403893 bytes, checksum: d4a408b351ce111149edf4edcb559e98 (MD5) Previous issue date: 2008-04-10 / Servico Nacional de Aprendizagem Comercial / The present research is aimed to investigate leisure and its articulation with the education, through the students and professors conceptions, in a college extension course about growing old and education, in a teaching institution located in the city of São Paulo. I highlight as presumptive, the ignorance, considering the extension of the themes, leisure and education associated to the process of growing old. This term was developed, based on theoretical aspects observing leisure concepts indicated by researchers of the area. Its relations to questions such as time, attitude, lived culture, activities, space; and the articulation which exists, with the possibility of permanent education, as well as the search for improvement of life quality, inserted in the process of growing old, from the students and professors conceptions in a college extension course about education and the growing old period / A presente pesquisa tem por objetivo investigar o lazer e a sua articulação com a educação, através das concepções de alunos e professores de um curso de extensão universitária sobre Educação e Envelhecimento , de uma instituição de ensino, localizada no município de São Paulo. Destaco como pressuposto, o desconhecimento quanto à amplitude das temáticas Lazer e Educação associados ao processo de envelhecimento. O trabalho é desenvolvido com base nos aspectos teóricos, observando as concepções de lazer indicadas por pesquisadores da área; suas relações com questões como o tempo, a atitude, a cultura vivida, as atividades, os espaços; e a articulação existente com a possibilidade de educação permanente assim como a busca pela melhoria da qualidade de vida em meio ao processo de envelhecimento, a partir das concepções de alunos e professores de um curso de extensão universitária sobre Educação e Envelhecimento

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