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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.
41

Internationalisering i den svenska förskolan : En studie om förskollärares syn på Läroplan för förskolans mål om internationalisering / Internationalisation in Swedish preschool : A study of preschool teachers´perspectives of the Swedish curriculum internationalisation goal

Al-Rufeye, Cecilia January 2022 (has links)
Syftet med studien är att undersöka och synliggöra förskollärares upfattning om Läroplan för förskolans (Skolverket, 2018) mål om internationalisering genom de diskurser som framträder utifrån deras texter. Syftet är vidare att genom deras texter och språkbruk analysera deras uppfattningar om hur de arbetar för att uppnå detta mål. Studien är en kvalitativ enkätundersökning som utgår från två forskningsfrågor som besvarats av 12 förskollärare från två olika skolområden i en mindre kommun i Mellansverige. Studien utgår från en diskursanalys där empirin analyseras genom att bearbeta informanternas texter.  Den teoretiska utgångspunkten i studien är Bronfenbrenner´s (1979) utvecklingsekologiska teori, som även används för att analysera resultatet tillsammans med det interkulturella och monokulturella perspektivet.  Förskollärarna beskriver en positiv bild av läroplansmålet där man tydligt kan se en vilja att arbeta kring det mångkulturella uppdraget. Flera av informanterna beskriver att de upplever en osäkerhet kring hur de ska uppnå det. Dock ser de arbetet som positivt och viktigt.  Resultatet ses utifrån Bronfenbrenners utvecklingsekologiska modell och lyfts av de diskurser som framkommit. Resultatet visar att majoriteten av informanterna lyfter Läroplanen som en utgångspunkt för deras arbete kring internationalisering. Det visar även att de flesta informanterna ser på arbetet kring internationalisering utifrån ett interkulturellt perspektiv. Dock synliggörs ett monokulturellt perspektiv hos vissa av informanterna vilket framgår av en viss positionering. Vissa förskollärare lyfter att det mångkulturella arbetet endast berör barngrupper med etnisk mångfald. / The purpose of this study is to explore and enlighten preschool teachers´perspectives of the Swedish curriculum internationalisation goal through the discourses that appear from their texts. The purpose is also to make it visible from their texts and language use of how they work to achieve the goal. The study is a qualitative survey that enlightens the two questions at issue. These questions are answered by 12 preschool teachers working in a preschool district in the middle of Sweden.  The study is based on a discourse analysis where the empirical data is analysed by processing the informants´texts.  The theoretical framework is Bronfenbrenner´s (1979)  developmental ecology theory. This theory, combined with the intercultural and the monocultural perspective are used in the analysis of the data.  Preschool teachers describe a positive viev on the goal of the Swedish curriculum as well as a strong will to work towards achieving the goal of internationalisation. Many informants admit to not being sure on how to achieve the goal. However, they view thistype of work as positive and important. The results are seen from Bronfenbrenners ecological model and from the discourses that appeared. The result show that most of the informants lifts the curriculum as a ground for their work with internationalisation. It also shows that most of the informants view their work of internationalisation from an intercultural perspective. There is also evidence of a monocultural perspective expressed by some of the informants which appears through some positioning discourse. Some teachers described multicultural work as something that only affects groups of children with ethnic diversity.
42

The Aesthetics of Unease: Telepresence Art and Hyper-Subjectivity

Haden, Heather Jean 13 May 2015 (has links)
No description available.
43

Soil Microbial Ecology Associated with Disease Control of Fusarium oxysporum f. sp.Cucumerinum in Cucumis sativus Cultivation

Kendall, Joshua Robert Allen 15 October 2015 (has links)
No description available.
44

Régulations microbiennes et rhizosphériques des cycles du carbone et de l'azote dans les systèmes de culture conventionnels et innovants / Microbial and rhizospheric regulations of carbon and nitrogen cycles in conventional and innovative cropping systems

Cros, Camille 15 February 2019 (has links)
La présence de plantes accélère la décomposition de la matière organique du sol (MOS) au travers de l’apport de composés riches en énergie (rhizodépôts et litières) stimulant les microorganismes ; un phénomène appelé « rhizosphere priming effect » (RPE). Une augmentation de la photosynthèse, activité pourvoyeuse d'énergie rhizodéposée, pourrait augmenter le RPE et l’offre du sol en nutriments. Récemment, le modèle SYMPHONY couplant activités photosynthétiques et microbiennes du sol suggère un ajustement de l'offre du sol en nutriments (delta minéralisation-immobilisation) à la demande des plantes. Cependant, le rôle clé de la photosynthèse sur cet ajustement offre-demande reste à étudier expérimentalement.L’objectif général de la thèse est d'étudier le rôle des interactions des activités photosynthétiques et microbiennes du sol dans les régulations des flux de carbone (C) et d'azote (N) des écosystèmes. Trois écosystèmes types ont été étudiés : la prairie, la monoculture de blé et un nouveau système de culture (NSC) associant blé et plantes pérennes de la prairie. Nous émettons l’hypothèse que les plantes pérennes, via une activité photosynthétique pourvoyant les microorganismes en énergie tout au long de l'année, sont essentielles à l'ajustement offre-demande en N. De nombreux défis techniques ont été relevés afin de construire une plateforme expérimentale de 40 mésocosmes sous éclairage et température naturels. Cette plateforme permet de coupler marquage 13C des plantes, mesures continues des échanges de CO2, du RPE, de la production végétale, du stockage de C du sol, le taux de minéralisation-immobilisation d'N et du lessivage d'N. Ce dispositif nous a permis de déterminer la contribution du RPE dans les flux de C des écosystèmes comprenant la production nette de l’écosystème (NEP), la production primaire brute (GPP) et la respiration de l’écosystème (RE) exprimées en g C m-2 24h-1. Nous avons montré une relation positive linéaire entre (1) RPE et GPP et (2) RPE et biomasse aérienne (AGB) (g C m-2). A partir de ces relations, le RPE peut être prédit en utilisant les équations suivantes : (...). Nous montrons un ajustement offre-demande de l’N au cours des saisons : une forte activité photosynthétique (printemps) est liée à un RPE et un delta minéralisation-immobilisation d’N élevés alors qu’une faible activité photosynthétique (automne) est liée à un RPE et un delta minéralisation-immobilisation d’N faibles. Cet ajustement était observé dans la prairie et dans le NSC mais pas en monoculture de blé. Logiquement, la lixiviation d’N était importante en monoculture de blé alors qu’elle était quasi nulle en prairie et dans le NSC. Après deux années de maintien des trois écosystèmes types, la production aérienne totale du NSC était équivalente à la prairie, tous deux étant supérieurs d’environ un facteur deux à la monoculture de blé. Ces résultats confirment l’importance des plantes pérennes dans la synchronisation offre-demande de l’N. L’ensemble de ces investigations souligne l’importance des activités des plantes et des processus rhizosphériques dans la régulation des cycles CN des écosystèmes. Ces régulations pourront être étudiées in situ et à l'échelle globale grâce aux proxys de ces processus rhizosphériques (RPE, ajustement offre-demande) déterminés dans la thèse. Des activités photosynthétiques et rhizosphériques tout au long de l'année sont essentielles à l'ajustement offre-demande en nutriments conduisant à une forte production primaire, à la fermeture des cycles des nutriments et au stockage de MOS. Ces découvertes offrent l'opportunité de construire de nouveaux systèmes de culture, à l'image de l’association blé-plantes pérennes étudiée, à hautes performances agro-environnementales. / The presence of plants accelerates the decomposition of soil organic matter (SOM) through the supply of energy-rich compounds (rhizodeposits and litter) stimulating microorganisms; a phenomenon called rhizosphere priming effect (RPE). An increase of photosynthesis, supplying soil with rhizodeposited energy, could increase the RPE and soil nutrients offer. Recently, the SYMPHONY model coupling photosynthesis and soil microbial activities suggested an adjustment of the soil nutrient offer (delta mineralization-immobilization) to plant demand. However, the key role of photosynthesis in this offer-demand adjustment needs to be investigated experimentally.The general objective of the thesis is to study the role of interactions between photosynthesis and soil microbial activities in the regulation of carbon (C) and nitrogen (N) fluxes of ecosystems. Three ecosystem types were studied: grassland, wheat monoculture and a new cropping system (NSC) where wheat and perennial grassland species were intercropped. We hypothesize that perennial species, through a continuous photosynthetic activity supplying microorganisms with energy over the year, are essential for offer-demand adjustment.Many technical challenges were overcame to build an experimental platform of 40 mesocosms under natural light and temperature. This platform allows to couple 13C labeling of plants, continuous CO2-exchange measurements, RPE, plant production, soil C storage, N mineralization-immobilization turnover and N leaching.This experimental platform allowed us to determine the contribution of RPE to C fluxes of ecosystems including net ecosystem production (NEP), gross primary production (GPP) and ecosystem respiration (ER) expressed in g C m-2 24h-1. We found positive linear relationships between (1) RPE and GPP and (2) RPE and aboveground biomass (AGB) (g C m-2). Using these relationships, the RPE can be predicted with the following equations: (...).We show an adjustment of soil N-offer to plant N-demand across seasons: a high photosynthetic activity (spring) is linked to high RPE and delta mineralization-immobilization of N whereas a low photosynthetic activity (autumn) is linked to low RPE and delta mineralization-immobilization of N. This adjustment was observed in grassland and NSC but not in wheat monoculture. Consistently, N leaching was high in wheat monoculture while it was almost null in grassland and NSC. After two years of establishment of the three ecosystems, the total aboveground production of the NSC was equivalent to the grassland, each being about twice as high as the wheat monoculture. These results confirm the importance of perennial species in the offer-demand adjustment of N.Our findings underline the importance of plant activities and rhizosphere processes in the regulation of ecosystems C N cycles. Using the proxies of rhizosphere processes (RPE, offer-demand adjustment) provided in the thesis, further studies could investigate these regulations in situ and at the global scale. The presence of photosynthetic and rhizospheric activities over the year are essential for offer-demand adjustment of nutrients leading to high primary production, closing nutrient cycles and SOM storage. These findings offer the opportunity to build new cropping systems such as the wheat-perennial species studied, with high agro-environmental performances.
45

Environment and health in Central Asia : quantifying the determinants of child survival

Franz, Jennifer Sue January 2007 (has links)
The impact of environmental degradation on well-being is largely ignored in terms of economic costs of development. Due in large part to measurement difficulties, the environment in the daily welfare of the world's poorest remains inadequately accounted for in development policies. The aim of this work is, therefore, to advance our understanding of the relationship between the environment and human health. Anthropogenic activities in Central Asia have severely disrupted the natural environment. The poorest, most vulnerable members of society are at an increased risk of mortality and a life-time of illness associated with worsening ecological conditions in the region. The work is by nature inter-disciplinary and pulls from many social sciences in an attempt to provide new insight into the role of long term environmental degradation and the impact on social welfare. There are three main original contributions of this work. Firstly, the research demonstrates the traditional emphasis in the literature on socioeconomic factors in explaining high rates of child mortality in Central Asia is inadequate. Secondly, for the first time in an international cross-section examining the determinants of child survival, the macro-level environment is put forth as a key determinant of excess child mortality in Central Asia. An improved measure of income is used for the first time in such a study to control for important distributional effects within and between countries. The results confirm the hypothesis that traditional determinants do not account for endemically high rates of mortality in the region. Secondly, using administrative (oblast) data from Uzbekistan, Chapter 6 presents the first study of its kind to incorporate important geographic as well as socioeconomic information in explaining variation in infant mortality due likely to ecological degradation. Ultimately, the findings demonstrate the environment must be adequately considered in all policy making aimed at improving health outcomes in the region.
46

Expanding Eco-Visualization: Sculpting Corn Production

Figg, Jennifer E 01 January 2015 (has links)
This dissertation expands upon the definition of eco-visualization artwork. EV was originally defined in 2006 by Tiffany Holmes as a way to display the real time consumption statistics of key environmental resources for the goal of promoting ecological literacy. I assert that the final forms of EV artworks are not necessarily dependent on technology, and can differ in terms of media used, in that they can be sculptural, video-based, or static two-dimensional forms that communicate interpreted environmental information. There are two main categories of EV: one that is predominantly screen-based and another that employs a variety of modes of representation to visualize environmental information. EVs are political acts, situated in a charged climate of rising awareness, operating within the context of environmentalism and sustainability. I discuss a variety of EV works within the frame of ecopsychology, including EcoArtTech’s Eclipse and Keith Deverell’s Building Run; Andrea Polli’s Cloud Car and Particle Falls; Nathalie Miebach’s series, The Sandy Rides; and Natalie Jeremijenko’s Mussel Choir. The range of EV works provided models for my creative project, Sculpting Corn Production, and a foundation from which I developed a creative methodology. Working to defeat my experience of solastalgia, Sculpting Corn Production is a series of discrete paper sculptures focusing on American industrial corn farming. This EV also functions as a way for me to understand our devastated monoculture landscapes and the politics, economics, and related areas of ecology of our food production.
47

Territorialização da monocultura de eucalipto e os impactos sobre a estrutura agrária no norte do Espírito Santo /

Lima, Adelso Rocha January 2016 (has links)
Orientador: Eduardo Paulon Girardi / Resumo: Este trabalho busca analisar a territorialização da monocultura de eucalipto e os impactos sobre a estrutura agrária no Norte do Espírito Santo. A partir da década de 1960, foi iniciado plantio de eucalipto em larga escala no Norte do Estado (ao norte do Rio Doce), principalmente em alguns municípios litorâneos, para abastecer a fábrica de papel e celulose instalada no município de Aracruz na década de 1970. Instalado inicialmente sobre as áreas de uso comunal de indígenas e quilombolas, nos municípios de Aracruz, São Mateus e Conceição da Barra, esse monocultivo foi sendo expandido para o conjunto dos municípios, dando uma nova configuração à estrutura agrária capixaba. Fibria, antiga Aracruz Celulose, e Suzano Papel e Celulose, duas empresas de grande influência no Espírito Santo e as maiores responsáveis pelos impactos na estrutura agrária capixaba, têm se utilizado da justificativa de demanda internacional de papel e celulose, mas também do Estado, enquanto financiador e legislador favorável a este projeto. Desterritorializando camponeses, provocando diversos conflitos e violência nesse período, em função dos impactos causados, como é o caso da concentração da terra e da produção, da formação do deserto verde, do bloqueio à reforma agrária, da questão ambiental, impactando o campo e a cidade. A análise documental, entre outras produções bibliográficas, foi a principal fonte de investigação, complementada a partir de pesquisa de campo, ouvindo lideranças de movimentos e do... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre
48

Influência do gado e da monocultura de eucalyptus sp. em florestas ripárias do sul do Brasil

De Marchi, Tiago Closs 11 January 2011 (has links)
Submitted by Silvana Teresinha Dornelles Studzinski (sstudzinski) on 2015-06-23T15:19:36Z No. of bitstreams: 1 TiagoClossDeMarchi.pdf: 3447572 bytes, checksum: 384491c29d57ca52c59ea0cda6879c8b (MD5) / Made available in DSpace on 2015-06-23T15:19:36Z (GMT). No. of bitstreams: 1 TiagoClossDeMarchi.pdf: 3447572 bytes, checksum: 384491c29d57ca52c59ea0cda6879c8b (MD5) Previous issue date: 2011 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A mudança do uso da terra decorrente de atividades agrícolas provoca uma modificação na paisagem que leva à criação de fragmentos florestais isolados que se mantém imersos em uma matriz que pode apresentar uma maior ou menor agressividade de acordo com o seu uso. Este estudo foi realizado em duas fazendas vizinhas localizadas no município de Eldorado do Sul, RS. A Fazenda Terra Dura, pertence à empresa Celulose Riograndense S/A e a maior parte da área é utilizada para a monocultura de eucalipto (Eucalyptus spp.). Os remanescentes de floresta nativa estão exclusivamente associados aos diversos cursos d’água que cruzam a área e cercados pelo plantio de eucalipto de diversas idades e estágios de produção. A área é utilizada para o plantio de eucalipto há cerca de 30 anos e há 20 foi isolada do gado. A Fazenda Eldorado destina-se à criação extensiva de gado e sua cobertura vegetal é caracterizada por um predomínio de campo com fragmentos de florestas ripárias que o gado utiliza como local de pastejo e desedentação. Em cada uma das dez áreas selecionadas foram alocados dois transectos paralelos ao curso d’água a 20 metros de distância um do outro nos quais foram aleatorizadas cinco unidades amostrais de 10 x 10m para amostragem do componente arbóreo dos fragmentos. Em cada unidade amostral foram registradas a circunferência de todos os indivíduos com diâmetro a altura do peito maior ou igual a 5 cm (DAP ≥ 5cm). O componente juvenil foi amostrado em unidades amostrais de 5 x 5m concêntricas em cada parcela de 10 x 10m, onde foram amostrados todos os indivíduos com mais de um metro de altura e com menos de 5 cm de diâmetro e estimou-se sua altura total e seu diâmetro à altura do solo (DAS). A densidade e composição do estrato herbáceo foi amostrada em parcelas de 1 x 1 m concêntricas às unidades amostrais de 5 x 5 m. Nestas unidades amostrais foi removida toda vegetação de até 1 m de altura e identificadas taxonômicamente as espécies e separadas em formas de vida (árvore, arbusto, erva, gramíneas, pteridófita, trepadeiras, epífitos). Para avaliação do sub-bosque nos plantios de eucalipto foram selecionados quatro talhões onde foram alocados três transectos de 100 m de comprimento em diferentes distâncias da borda (5, 25 e 50 m) e dois transectos (5 e 25 m) para o interior da mata ciliar. Em cada transecto foram sorteadas cinco unidades amostrais de 5 x 5 m e amostrados todos os indivíduos juvenis utilizando os mesmos critérios anteriormente citados para este estrato. Nos fragmentos adjacentes aos plantios de eucalipto, foram encontradas 61 espécies para os adultos e 77 para os juvenis e o estoque de carbono estimado foi de 106 Mg.ha-1 para os indivíduos adultos e de 4,3 Mg.ha-1 para os herbáceos. Nas áreas com presença de gado foram amostradas 62 espécies para os adultos e 48 para juvenis, com um estoque de carbono de 85,5 Mg.ha-1 para adultos e 0,9 Mg.ha-1 para herbáceo. No sub-bosque dos plantios de eucalipto foram amostradas 32 espécies, sendo 16 exclusivas e 71 no interior da floresta ripária, com 55 exclusivas. Os resultados mostraram que florestas em pequenos fragmentos incorporados em plantações de eucalipto parecem ser melhor preservadas do que aqueles expostos à pecuária. Além disso, áreas com presença de gado apresentaram uma redução no estoque de carbono de 23,8% para o estrato arbóreo e de 79,4% no estrato herbáceo em relação às áreas sem a presença de gado. A plantação de eucalipto possui um importante papel, embora restrito devido ao curto período de corte das árvores, para a manutenção da diversidade de espécies de florestas nativas adjacentes em seu sub-bosque e podem atuar como uma catalizadoras da regeneração da vegetação nativa e na manutenção da diversidade local. / The change in land use due to agricultural activities causes a landscape change that leads to the creation of isolated forest fragments that remain embedded in a matrix that may present a greater or lesser aggressiveness according to their use. The environmental quality of this matrix can affect species composition and forest structure through several factors that impact the surrounding environment, but on the other hand, depending on its type, the array can act as an important source of biodiversity conservation. This study was conducted in two neighboring farms located in Eldorado do Sul, RS. Terra Dura Farm, owned by Celulose Riograndense S/A and most of the area is used for the monoculture of eucalyptus (Eucalyptus spp.). The remnants of native forest are exclusively associated with the various streams that cross the area and surrounded by eucalyptus plantations of various ages and stages of production. The area is used for the planting of eucalyptus during 30 years. The cattle was isolated 20 years ago. Eldorado Farm is intended for extensive cattle ranching and its vegetation is characterized by a predominance of field with fragments of riparian forests that livestock use for grazing. We survey ten riparian fragments, five in each farm, were allocated two transects parallel to the stream to 20 m away from each other in which five were randomized plots of 10 x 10 m sampling of the tree component of the fragments. In each sampling unit circumference were recorded for all individuals with diameter at breast height greater than or equal to 5 cm (DBH ≥ 5 cm). The juvenile component was sampled in 5 x 5 m plots concentric in each plot of 10 x 10 m was sampled all individuals with more than one meter in height and less than 5 cm in diameter and estimated its total height, and its diameter at ground level (DAS). The density and composition of the herbaceous layer was sampled in plots of 1 x 1 m plots of concentric to 5 x 5 m. In these sample units of all vegetation was removed up to 1 m high, which were taxonomically identified and separated in life forms (tree, shrub, herb, grass, fern, lianes and epiphytes). To evaluate the understory in the eucalyptus plantations were selected four plots were allocated three transects of 100 m length at different distances from the edge (5, 25 and 50 m) and two transects (5 and 25 m) into the riparian vegetation. In each transect were randomly selected five samples of 5 x 5 m and sampled all juveniles using the same criteria previously cited for this stratum. In fragments adjacent to eucalyptus plantations, 61 species were found for adults and 77 for juveniles and the estimated carbon storage was 106 Mg.ha-1 for adults and 4.3 Mg.ha-1 for the herbs. In areas with presence of cattle were sampled for 62 adults and 48 for juveniles, with a carbon stock of 85.5 Mg.ha-1 for adults and 0.9 Mg.ha-1 for herbaceous. In the understory of the eucalyptus plantations were found 32 species, with 16 exclusive and 71 within the riparian forest, with 55 exclusive. Our results showed that in small forest fragments embedded in eucalypt plantations seem to be better preserved than those exposed to livestock. In addition, areas with the presence of cattle showed a reduction in carbon stock of 23.8% for the upper stratum and 79.4% in the herbaceous layer compared to areas without the presence of livestock and the planting of eucalyptus has an important role, although limited, due to shortcut the trees for the maintenance of species diversity of native forest adjacent to their understory and can act as a catalyst of the regeneration of native vegetation and maintenance of local diversity.
49

Tree transpiration inforest plantations: Effects of species, seasonality and diversity (Panama) / BAUMTRANSPIRATION IN FORSTLICHEN PLANTAGEN: EFFEKTE VON ARTEN, SAISONALITÄT UND DIVERSITÄT (PANAMA)

Kunert, Norbert 09 June 2010 (has links)
No description available.
50

Diversity of rice weeds vegetation and its potential as local forage resource in Java, Indonesia

Kumalasari, Nur 11 June 2014 (has links)
No description available.

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