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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.
581

Characterisation in isiXhosa drama with specific reference to two isiXhosa dramas

Nweba, Lena 04 1900 (has links)
Thesis (MA)--Stellenbosch University, 2004. / ENGLISH ABSTRACT: The main aim of study is to investigate characterisation in two of Ngewu's dramas. Ngewu's dramas are contemporary and many scholars have not yet had time to research them. The story in the drama Amadada la afunani ezintsaneni ?( 1998), is about the sexual abuse of children. This is new because the abuse of small children is not seen to indicate culture especially now that even fathers abuse their children. In the olden days children used to look to grown -ups for protection of every kind. The story in the second drama Yeha Mfazi Obulala Indada (1997) , is about a wife who hires assassins to kill her husband. In the past wives were submissive to their husbands. It was unheard of a wife challenging the husband's authority, let alone hiring assassins to kill him. Chapter 1 introduces the aim, the scope, the theories and the methods of the study. Chapter 2 deals with the plot structure of the dramas Amadada la afunani ezintsaneni? (1998) and Yeha Mfazi Obulala Indada (1997) Chapter 3 deals with characterisation in isiXhosa dramas, Amadada la afunani ezintsaneni(1998) and Yeha Mfazi Obulala lndoda (1997) Chapter 4 deals with language and the pattern of stylistic devices Chapter 5 concludes the findings of the study. / AFRIKAANSE OPSOMMING: Die hoofdoel van hierdie studie is om die karakterisering in twee van Ngewu se dramas te ondersoek. Ngewu se dramas is hedendaagse daarom is daar nog veel navorsing daaroor ezintsaneni (1998) gedoen nie. Die storie in die drama Amadoda la afunani handel hoofsaaklik oor die seksuele molestering van kinders. Seksuele kindemolestering is In relatiewe nuwe versknser want dit is taboe in kultuur veral nou dat die bekend is dat kinders deur hulle vaders gemolesteer word. In vroeer jare was kinders van volwassens afhanklik vir beskermering en welvaart. Die tweede drama Yeha Mfazi Obulala lndoda (1997) handeloor I vrou wat sluipmoordenaars huur om haar man om die lewe te bring. In vroeer jare was vroue aan hul mans onderdaning. Dit was ongewoon dat I vrou haar man se gesag sou ondermyn, en nog meer ondenkbaar die huur van sluipmoordenaars om hom om die lewe te bring. In hoofstuk 1 vind ons die doel van die studie, die omvang ,teoretiese raamwerk en metode van die studie. Hoofstuk 2 handeloor die struktuur van die twee Amadoda la afunani ezintsaneni (1998) en Yeha Mfazi Obulala Indoda ( 1997) Hoofstuk 3 handeloor die karakterisering in die isiXhosa dramas, Amadoda la afunani ezintsaneni (1998) en Yeha Mfazi Obulala Indoda (1997) Hoofstuk 4 handeloor die taal en skryfstyl van die skrywer. Hoofstuk 5 bevat die samevatting van die studie.
582

Procédé novateur d'extraction de jus de fruits par micro-onde : viabilité de fabrication et qualité nutritionnelle des jus / Extraction of fruit juices by microwave hydrodiffusion : tests and nutritional juice quality

Cendres, Aurélie 29 September 2010 (has links)
Le procédé innovant d’hydrodiffusion par micro-onde a été testé et validé pour la fabrication de jus de fruit sur des raisins, abricots et prunes. Ce procédé présente des avantages au niveau technique : rapidité d’extraction, pas de préparation de l’échantillon, aucun auxiliaire de fabrication. Il permet l’obtention de jus à partir de fruits difficiles à presser, avec une pasteurisation « in line » et des produits se différenciant nettement des jus commerciaux par leur couleur et texture.Le jus est expulsé du fruit sous l’effet de la vapeur produite in situ. A partir du fruit congelé, la déstructuration liée à la croissance des cristaux de glace facilite l’extraction. Les rendements le plus élevés sont obtenus à partir de fruits congelés, et à basse puissance. Une partie de l’eau des fruits est convertie en vapeur, mais peut être récupérée en utilisant un réfrigérant, ce qui permet d’atteindre des rendements proches des rendements de jus obtenus avec un prétraitement enzymatique et pressurage. Globalement, le jus a une composition proche de celle du jus présent dans le fruit ou obtenus par pressurage. La composition du jus expulsé des fruits change au cours de l’extraction. La concentration des composés présents dans la chair et hydrosolubles (sucres, acides, acides phénoliques) baisse nettement en fin d’extraction, tandis que les anthocyanes, présentes dans l’épiderme des raisins ou des prunes, montrent un pic de concentration lors de la phase d’expulsion rapide des jus. La teneur en procyanidines est nettement plus élevée que pour des jus obtenus par pressurage / The hydrodiffusion process was tested and validated for production of juices from grapes, apricots and plums. Its major advantages are speed, no sample preparation, no processing aid. It allows production of juices from hard-to-press fruits with an in line pasteurisation. The juices present original characteristics notable bright colours, texture, and a fresh fruit aroma.The juice is expulsed from the fruit by the pressure due to in situ vapour generation. The destructuration occuring in frozen fruits due to growth of ice crystals facilitate the juice expulsion. The highest yields are obtained from frozen fruits and at low power densities. Part of the water from the fruits is vaporised, and can be collected by use of a cooler, allowing to reach yields comparable to those obtained by pressing after an enzymatic pre-treatment. Juice composition is close to that of juice extracted by pressing, though with slightly lower concentrations of most soluble solids. The composition of juice changes along the extraction. The highly soluble compounds present in the fruit flesh mostly show a clear exhaustion at the end ofextraction. Anthocyans, present exclusively in the peel of the test fruits, present a maximum during the fast juice extraction phase. Procyanidin concentrations is much higher in juices obtained by hydrodiffusion than in conventional juices
583

Interactions plante - pollinisateur : caractérisation de la qualité du pollen de deux cucurbitacées durant son ontogenèse, sa présentation et son transport sur le corps de l'abeille domestique / Plant – pollinator interactions : characterisation of pollen quality during its ontogenesis, its presentation and its transport on honey bee body in two cucurbitaceae

Dibos, Chloé 14 December 2010 (has links)
Chez de nombreuses Angiospermes, la pollinisation croisée est nécessaire pour le succès de la reproduction. La plupart de ces plantes ont évolué afin de favoriser la pollinisation entomophile, principalement assurée par les abeilles. C’est le cas des Cucurbitacées, dont le melon (Cucumis melo L.), importante culture du sud de la France et le concombre d’âne (Ecballium elaterium (L.) A. Rich.) plante spontanée endémique du bassin méditerranéen, les deux modèles de cette étude. Afin de mieux comprendre les relations plante-pollinisateur,nous avons choisi de caractériser le couple pollen de Cucurbitacées/abeille domestique (Apis mellifera L.) à travers la production de pollen, sa présentation sur la fleur et son transport sur l’abeille. Nous avons montré que, chez ces plantes, l’ontogenèse du pollen s’accompagne d’erreurs développementales conduisant à la formation de près de 3% de grains de pollen vides. De plus, nous avons mis en évidence que chez E. elaterium, des erreurs méiotiques entraînaient la formation de grains de pollen génétiquement anormaux qui pourraient être source d’autopolyploïdie. Chez C. melo, nos résultats ont révélé que la mise en contact du pollen avec le milieu environnant entraîne une baisse de 30% de sa viabilité, mais que celle-ci reste stable jusqu’à la fin de l’anthèse. L’aptitude à germer, quant à elle, finit d’être acquise juste avant anthèse et décroît de 12% en fin de période d’anthèse. Nous avons montré que le pollen de C. melo transporté sur le corps de l’abeille pouvait soit avoir une viabilité et une aptitude à germer préservée, probablement par protection contre la déshydratation, soit perdre quasi-totalement sa viabilité et son aptitude à germer. Enfin, nous avons détecté des composés biochimiques spécifiques des abeilles protégeant ou diminuant la qualité reproductrice du pollen / For many flowering plant species cross pollination is necessary to ensure reproductive success. Most of these plants have evolved to encourage insect pollination which is mainly carried out by bees. Such is the case of plants in the Cucurbitaceae family, including the cantaloupe (Cucumis melo L.), an important crop of the South of France, and squirting cucumber (Ecballium elaterium (L.) A. Rich.), a wild plant restricted to the Mediterranean Basin, the two vegetal models used in this study. To better understand plant-pollinator relations, we proposed to characterise the interaction between Cucurbitaceae pollen and the honey bee (Apis mellifera L.) through pollen production, its presentation and its transport on the honey bee body. Our results showed that developmental anomalies took place during pollen ontogenesis in these species leading to 3% of the pollen grains produced to be empty. Moreover, we demonstrated that meiotic abnormalities in E. elaterium leading to the production of genetically abnormal pollen grains could be a source of autopolyploidy. At anthesis in C. melo, our results showed that pollen viability decreased to 30% when pollen was exposed to environmental conditions, then remained stable during the period of anthesis.The ability for pollen to germinate was completed just before anthesis then decreased to 12% at the end of anthesis. We determined that viability and germinability of cantaloupe pollen carried on the honey bee body can be enhanced or decreased according to which specific honey bee biochemical compounds were detected
584

Efeito residual do lodo de esgoto na produtividade e na ciclagem de nutrientes em plantios de Eucalyptus grandis e no cultivo de plantas alimentícias (simulando alteração do uso agrícola do solo) / Long term effect of the sewage sludge on productivity and nutrient cycling in Eucalyptus grandis stands and in food plants cultivation (simulating change in the agricultural use of the soil)

Ferraz, Alexandre de Vicente 22 January 2014 (has links)
Nas ultimas décadas, a elevação do consumo e do custo dos fertilizantes minerais tem preocupado o setor agrícola mundial. Portanto, o uso do lodo de esgoto tratado (biossólido) como adubo está sendo incentivado em diversos países, visto que aumenta a produtividade e gera benefícios pela reciclagem da matéria orgânica e nutrientes contidos em sua composição. Ainda assim, a presença de elementos potencialmente tóxicos (ex. metais pesados) no lodo e a falta de conhecimento sobre o seu efeito residual no ambiente, principalmente, em casos onde há a alteração do uso agrícola do solo, têm contribuído para a sua disposição final em aterros sanitários. Esta pesquisa pressupõe que o uso agrícola do lodo de esgoto, mesmo algum tempo após a sua aplicação ao solo, continua exercendo efeito residual favorável sobre a produtividade (biomassa) e a ciclagem de nutrientes em plantios de eucalipto, bem como em culturas de plantas alimentícias. No município de Itatinga-SP, foram instalados três experimentos com povoamentos de Eucalyptus grandis, sendo: (1) Prática de desbaste em dois talhões de eucalipto plantados em 1998, sobre Latossolo Vermelho-Amarelo (LVA) e Latossolo Vermelho Escuro (LVE), e adubados com 20 t ha-1 lodo de esgoto; (2) Prática da talhadia (condução de rebrota) em parcelas cultivadas com eucalipto e adubadas (em 2003) com 10, 20 e 30 t ha-1 de lodo de esgoto, aplicadas na forma úmida (torta) e seca (granulado) e (3) Prática de reforma em parcelas de eucalipto adubadas (em 2005) com 15 t ha-1 dos lodos produzidos pelas estações de tratamento de esgoto de Barueri, São Miguel e Parque Novo Mundo. Um quarto experimento procurou simular a alteração do uso agrícola do solo, pela substituição de povoamentos de eucaliptos adubados com lodo de esgoto (há catorze anos) por áreas de cultivo das espécies: Lactuca sativa L. (alface), Raphanus sativus L. e Oryza sativa L. (arroz de sequeiro). Neste experimento, as plantas foram cultivadas em vasos preenchidos com dois tipos de latossolo (LVA e LVE), ambos coletados em talhões de E. grandis adubados há catorze anos com lodo de esgoto. De modo geral, a adubação dos plantios de eucalipto com os lodos de esgoto elevou o teor de fósforo, cálcio e zinco no solo. Nas áreas de desbaste, as concentrações foliares de nutrientes foram mais elevadas nas árvores cultivadas sob efeito residual do lodo de esgoto; todavia, este efeito não foi suficiente para alterar o crescimento do tronco (em circunferência) das árvores. Na área de talhadia, a adubação com 10 t ha-1 de lodo de esgoto aplicado seco exerceu efeito residual positivo sobre a produção de biomassa aérea. Na área de reforma, a biomassa acumulada pelas árvores cultivadas sob efeito residual do lodo foi superior (até 150%) em relação à testemunha; além disso, este efeito residual do lodo trouxe reflexos positivos também na ciclagem de nutrientes, devido à maior deposição de folhedo. Sob o efeito residual do lodo de esgoto, as plantas alimentícias acumularam 2 a 5 vezes mais biomassa em relação ás respectivas testemunhas, principalmente ao serem cultivadas no LVA. Essas plantas apresentaram, também, concentrações mais elevadas de cádmio nas folhas, bem como de cromo e níquel nas raízes; todavia, em nenhum dos cultivos, foram excedidos os limites de metais pesados preconizados pela Agência de Vigilância Sanitária (ANVISA) do Brasil. / Over the last few decades, the increase in consumption and in the cost of mineral fertilizers has concerned overall agriculture. Therefore, the use of treated sewage sludge (biosolids) as fertilizer has being encouraged in many countries, inasmuch as it increases productivity and generates benefits by the recycling of organic matter and nutrients in its composition. Nevertheless, the presence of potentially toxic elements (e.g. heavy metals) in the sludge and the lack of knowledge about its long term effect on the environment, especially in cases where there is a change in agricultural use, have contributed to its final disposal in landfills. This research assumes that the agricultural use of sewage sludge, even some time after its application to the soil, have a favorable long term effect on productivity (biomass) and nutrient cycling in eucalypt stands, as well as in cultures of food plants. For this study, three experiments with Eucalyptus grandis were installed in Itatinga/SP: (1) Thinning practice in two eucalyptus stands planted in 1998, on sandy and clayey ferralsol (LVA and LVE, by its acronym in Portuguese), both fertilized with 20 t ha-1 of sewage sludge; (2) Coppicing practice (sprouting conduct) in eucalyptus plots fertilized (in 2003) with 10, 20 and 30 t ha-1 of wet and dry sewage sludge; and (3) Reform techniques in eucalyptus plots fertilized (in 2005) with 15 t ha-1 of sludge produced by Barueri\'s, São Miguel\'s and Parque Novo Mundo\'s wastewater treatment plants. A fourth experiment simulated the change of use of agricultural soil, by replacing eucalyptus stands fertilized with sewage sludge (fourteen years ago) for vegetable species: Lactuca sativa L. (lettuce), Raphanus sativus L. (radish) and Oryza sativa L. (upland rice). In this experiment, plants were grown in pots filled with two types of ferralsol (LVA and LVE), both collected in E. grandis stands fertilized with sewage sludge (14 years ago). In general, the eucalyptus stands fertilization with sewage sludge increased the phosphorus, calcium and zinc content in the soil. In thinning stands, the leaf nutrient concentrations were greater in trees grown under long term effect of sewage sludge; however, this effect was not sufficient to alter the growth of the trunk (in circumference). In coppice stands, the fertilization with 10 t ha-1 of dry sewage sludge had positive long term effect on the biomass production. In areas undergoing stand reform, the biomass accumulated by trees grown on long term effect of the sewage sludge was greater (150%) than the control. Furthermore, this effect of the sludge also brought positive impacts on nutrient cycling, due to an increasing in the leaf fall production. Under the long term effect of sewage sludge, the food plants accumulated 2 to 5 times more biomass than respective control treatments, especially if they are grown on the LVA. These plants also showed greater cadmium concentrations in the leaves, as well as greater chromium and nickel concentration in the roots. However, the concentrations of heavy metals didn\'t exceed the limits recommended by the Brazilian Health Surveillance Agency (ANVISA, by its acronym in Portuguese) in any of the crops.
585

Impact de l'administration des probiotiques sur les infections respiratoires / Impact of probiotic administration on respiratory tract infections

Belkacem, Nouria 06 June 2017 (has links)
Les probiotiques font partie du microbiote commensal. Ils ont le potentiel de stimuler la réponse immunitaire intestinale et systémique. Le virus de la grippe est à l’origine de morbidité importante. De plus, il favorise les infections bactériennes secondaires telles que Neisseria meningitidis. Nous nous sommes intéressés à l’étude des mécanismes de protections conférées par la souche Lactobacillus paracasei CNCM I-1518 sur une infection par le virus de la grippe dans un modèle de souris. Nos résultats ont montré que le gavage des souris avec la souche L. paracasei pendant 7 jours avant l’infection grippale a permis une activation des cytokines pro-inflammatoires et un recrutement massif des cellules immunitaires dans les poumons. Cette activation du système immunitaire est responsable après infection grippale d’une meilleure clairance du virus de la grippe et d’une réponse inflammatoire moins importante comparée aux souris témoins. L’administration orale à des souris du peptidoglycane de la souche L. paracasei a permis de retrouver partiellement le phénotype protecteur observé avec la bactérie entière. Les effets protecteurs induits par L. paracasei CNCM I-1518 lui sont spécifiques car l’utilisation de 2 souches L. rhamnosus CNCM I-3690 et L. paracasei CNCM I-3689 n’ont pas conférées aux souris une protection contre la grippe. L’étude de l’impact de la souche L. paracasei CNCM I-1518 sur une infection secondaire par N. meningitidis après infection grippale a montré que le gavage des souris par la souche L. paracasei permet un meilleur état clinique associé à une modulation de la réponse immunitaire et une clairance de l’infection bactérienne secondaire plus efficace / Probiotics are part of the commensal microbiota. They play a potential role in stimulating the intestinal and systemic immune response. Several clinical studies addressed beneficial effect of probiotics against respiratory infections in particular on influenza infections. These infections are responsible for significant morbidity. The burden of flu is also worsened by secondary bacterial infections such as Neisseria meningitidis. In this work, we investigated the mechanisms of protection against influenza infection conferred by Lactobacillus paracasei CNCM I-1518 strain in mice. Our results showed that, L. paracasei consumption allow an early activation of pro-inflammatory cytokines and a massive recruitment of immune cells in the lungs prior to influenza infection. This activation of immune system was associated with a faster clearance of influenza virus after infection. We able to show that feeding mice with purified peptidoglycan from L. paracasei reproduced partially the above mentioned effects observed with L. paracasei bacteria feeding.The protective effects induced by L. paracasei CNCM I-1518 against the flu infection are strain specific as L. rhamnosus CNCM I-3690 and L. paracasei CNCM I-3689, tested under the same conditions did not confer to mice protection against influenza infection. Subsequently, we investigated the impact of L. paracasei CNCM I-1518 on secondary bacterial infection with N. meningitidis following influenza infection. Our results showed that consumption of L. paracasei CNCM I-1518 strain was associated with a better clinical status and a modulation of the immune response with a better clearance of secondary bacterial infection
586

L'interface etre humain/technologie dans la Litterature Europeenne des Annees 60 a aujord'hui

Fenga, Valentina <1978> 07 June 2010 (has links)
No description available.
587

Variabilidade produtiva, tamanho de parcela e uso de bordaduras em experimentos com culturas olerícolas em ambiente protegido / Productive variability,plot size and borders use in experiments with cultures oleraceous environmental protected

Santos, Daniel 22 July 2016 (has links)
The work aimed to study the variability in protected environments cultivated with zucchini, lettuce, green bean, peppers and cherry tomatoes and test the use of borders and the handling of the plot size is effective in minimizing the variability in these experiments . In the study we used uniformity of test data in plastic greenhouse, which were as follows: two experiments with zucchini five with lettuce, three with green bean, two with chili and one with cherry tomatoes. In the analysis considered the existence of parallel rows of growing the lateral openings of the oven and columns perpendicular to these openings. Different settings were created by deleting lines and columns for generating the borders and also with the use of different sizes portion. For each setting performed a variance homogeneity test between the remaining lines and columns, and to calculate a general coefficient of variation. There is variability between rows and between columns in experiments with zucchini, lettuce, green bean and pepper in plastic greenhouse. The use of the lateral borders of plastic greenhouse is no benefit in terms of reduced coefficient of variation or reduction of the cases of variability between rows or columns. The use of a plot size equal to or more than two plants in experiments with zucchini, lettuce, green bean, and a plot size equal to or greater than ten plants for sweet pepper, provides homogeneity of variance between lines and columns. / O trabalho teve por objetivo estudar a variabilidade em ambientes protegidos cultivados com abobrinha italiana, alface, feijão-de-vagem, pimentão e tomate cereja e testar se o uso de bordaduras e a manipulação do tamanho de parcela é eficaz na minimização da variabilidade nesses experimentos. No estudo utilizou-se dados de ensaios de uniformidade em estufa plástica, que foram os seguintes: dois experimentos com abobrinha, cinco com alface, três com feijão-de-vagem, dois com pimentão e um com tomate cereja. Nas análises considerou-se a existência de linhas de cultivo paralelas as aberturas laterais da estufa e de colunas perpendiculares a essas aberturas. Diferentes cenários foram criados através da exclusão de linhas e de colunas para gerar as bordaduras e também com o uso de diferentes tamanhos de parcela. Para cada cenário realizou-se um teste de homogeneidade de variâncias entre as linhas e colunas remanescentes, além de ser calculado um coeficiente de variação geral. Existe variabilidade entre linhas e entre colunas em experimentos com abobrinha italiana, alface, feijão-de-vagem e pimentão em estufa plástica. O uso de bordaduras nas laterais da estufa plástica não traz benefícios em termos de redução do coeficiente de variação ou de diminuição dos casos de variabilidade entre linhas ou colunas. O uso de um tamanho de parcela igual ou superior a duas plantas em experimentos com abobrinha italiana, alface, feijão-de-vagem e um tamanho de parcela igual ou superior a dez plantas para a cultura do pimentão, proporciona homogeneidade de variâncias entre linhas e colunas.
588

SIMULAÇÃO DINÂMICA DA SOJA, MILHO E FEIJÃO, CULTIVADO SOB DIFERENTES REGIMES HÍDRICOS / DYNAMIC SIMULATION OF SOYBEANS, CORN AND BEAN, GROWN UNDER DIFFERENT WATER REGIMES

Vivan, Gisele Aparecida 15 January 2014 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / Agribusiness has high importance in the state of Rio Grande do Sul, with the incorporation of fundamental importance to maintain its competitiveness and attractiveness factor technologies. Irrigation has become among the leading technologies available, featuring as main advantages to increase productivity and reduce risks associated with droughts. The determination of productive crop responses via simulation models has elevated in recent years, combining the agricultural sector the possibility of predictions about various scenarios, among these, water availability, reducing time and costs. In the same way, performing historical analyzes of production and profitability are essential for decision making related to incorporeal technologies in agricultural practice. This study aims to determine, via simulation models, productive responses of soybean, maize and beans, grown under different water regimes by performing temporal and risk analysis of the results obtained for the region of Santiago, RS. The study was conducted in the municipality of Santiago (29° 09 'S and 54 ° 51 ' O), with crops of soybeans, corn and beans, calibration and validation of models for these cultures in the DSSat system being performed, and subsequent evaluation and compared to the available models for soybean and beans in RSAP system. In the models considered fit after evaluation, sequences of climatic data (1961-2010) and certain productive responses related to growing conditions in rainfed and under great water conditions being held temporal and annual profitability analysis were included. The Cropgro - Soybean, Ceres-Maize - and Cropgro Drybean, framed models obtained performance as very good, very good and good for simulation of the production of grain (PG) of soybean, corn and beans, respectively, and great for simulation maximum production of dry matter (MSM) for all cultures. In comparison to the productive field responses versus models available in the DSSat system and RSAP, it was observed that for soybean and bean, the simulations obtained with the DSSat minor variations for soybeans, and RSAP for beans, however, both systems showed variations considered satisfactory. For historical simulations, the upland, the three studied crops (soybean, maize and beans), showed significant reductions in production and consequent income due to the drought. In both conditions of crops (dryland and irrigated) the higher costs, income and income were associated with maize, followed by soy beans. Comparing irrigated with dryland, the bean crop showed the greatest increases in profit complementation function of water, followed by corn and soybeans. Conclude that the simulation models were presented as useful tools for determining the yield response of crops under study, and compared with rainfed crops irrigated, the last were more interesting technically and economically. / O agronegócio apresenta elevada importância no Estado do Rio Grande do Sul, sendo a incorporação de tecnologias fator fundamental para manter a sua competitividade e atratividade. A irrigação apresenta-se dentre as principais tecnologias disponíveis, apresentando como principais vantagens a elevação da produtividade e a redução de riscos associados as estiagens. A determinação das respostas produtivas das culturas via modelos de simulação tem elevado-se nos últimos anos, aliando ao setor agropecuário a possibilidade de previsões sobre diversos cenários, dentre estes, os de disponibilidade hídrica, com redução de tempo e custos. Neste mesmo sentido, a realização de análises históricas de produções e rentabilidades são essenciais para tomadas de decisão relacionadas a incorpação de tecnologias na prática agrícola. O presente trabalho tem como objetivo determinar, via modelos de simulação, as respostas produtivas das culturas da soja, milho e feijão, cultivadas sob diferentes regimes hídricos, realizando análise temporal e de risco dos resultados obtidos, para a região de Santiago, RS. O trabalho foi realizado para o município de Santiago (29°09 S e 54º51 O), com as culturas da soja, milho e feijão, sendo realizada a calibração e validação dos modelos relativos a estas culturas presentes no sistema DSSat; e posterior avaliação e comparação com os modelos disponíveis para as culturas da soja e feijão no sistema RSAP. Nos modelos considerados aptos após a avaliação, foram inseridas sequencias de dados climáticos (1961-2010) e determinadas as respostas produtivas referentes às condições de cultivo em sequeiro e sob ótima disponibilidade hídrica, sendo realizada análise temporal e de rentabilidade anual. Os modelos Cropgro-Soybean, Ceres-Maize e Cropgro-Drybean, obtiveram desempenho enquadrado como muito bom, muito bom e bom, para simulação da produção de grão (PG) das culturas da soja, milho e feijão, respectivamente e ótimo para simulação da produção de matéria seca máxima (MSM) de todas as culturas. Na comparação entre respostas produtivas à campo versus modelos disponíveis no sistema DSSat e no RSAP, observou-se que para as culturas da soja e feijão, as simulações realizadas com o DSSat obtiveram menores variações para a soja, e o RSAP para o feijão, porém, ambos os sistemas apresentaram variações consideradas satisfatórias. Para as simulações históricas, na condição de sequeiro, as três culturas estudadas (soja, milho e feijão), apresentaram significativas reduções de produção e consequente lucro em função do déficit hídrico. Em ambas as condições de cultivos (sequeiro e irrigado) os maiores custos; renda e lucro estiveram associado a cultura do milho, seguidos pelo feijão e soja. Comparando cultivo irrigado com o de sequeiro, a cultura do feijão foi a que apresentou maiores elevações de lucro em função da complementação hídrica, seguidas pelas culturas do milho e soja . Conclui-se que os modelos de simulação apresentaram-se como ferramentas úteis para a determinação das respostas produtivas das culturas em estudo, sendo que comparado cultivos de sequeiro com irrigados, os últimos apresentaram-se mais interessantes técnica e economicamente.
589

Variabilidade espacial e tamanho de parcela em experimentos com culturas olerícolas / Spatial variability and size of plot in experiments with vegetable crops

Santos, Daniel 20 February 2013 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / The study aimed to test the efficiency of the method Papadakis on increasing the quality of experiments with snap beans, zucchini, peppers and lettuce, and having efficiency, determine how to estimate the covariate and plot size for use in experiments where apply the method. The definition of the form of estimated covariate that provides greater efficiency and calculation method Papadakis plot size adjusted for use in this method were made from the following blank experiments: two experiments with zucchini, lettuce with eight, five-bean pod and two peppers. In experiments with zucchini, pole beans and peppers, the variable was the weight of fruits and lettuce in experiments with variable mass was fresh shoot. The effectiveness of the use of analysis of covariance (ANCOVA) with the covariate estimated by Papadakis was tested from treatment experiments: one with the bell pepper crop, where the variable was the weight of fruit and one with lettuce crop where the variable was the fresh weight of shoots. The use of ANCOVA with the covariate estimated by Papadakis increases the quality of experiments with vegetable crops. The covariate that provides the highest efficiency ANCOVA is that which is determined considering a portion neighboring each side of the reference portion towards the row of plants. The plot size in the crop row, adjusted for method, is 10 plants (2.0 m) for snap beans, five plants (4.5 m) to zucchini, five plants (1.5 m ) for chili, and four plants (1.2 m) for lettuce. / O trabalho teve por objetivo testar a eficiência do método Papadakis no aumento da qualidade de experimentos com feijão-vagem, abobrinha italiana, pimentão e alface e, havendo eficiência, determinar a forma de estimativa da covariável e o tamanho de parcela para uso em experimentos onde se aplicará o método. A definição da forma de estimativa da covariável que proporciona maior eficiência do método Papadakis e o cálculo do tamanho de parcela ajustado para uso no mesmo foram realizados a partir dos seguintes experimentos em branco: dois experimentos com abobrinha italiana, oito com alface, cinco com feijão-vagem e dois com pimentão. Nos experimentos com abobrinha italiana, feijão-vagem e pimentão, a variável foi o peso de frutos e nos experimentos com alface a variável foi massa fresca da parte aérea. A eficácia do uso da análise de covariância (ANCOVA) com a covariável estimada pelo método Papadakis foi testada a partir de experimentos com tratamentos: um com a cultura do pimentão, onde a variável foi o peso de frutos e, um com a cultura da alface, onde a variável foi a massa fresca da parte aérea. O uso de ANCOVA com a covariável estimada pelo método Papadakis aumenta a qualidade de experimentos com culturas olerícolas. A covariável que proporciona a maior eficiência da ANCOVA é aquela que é estimada considerando uma parcela vizinha de cada lado da parcela de referência no sentido da linha de cultivo. O tamanho de parcela na linha de cultivo, ajustado para uso do método, é de 10 plantas (2,0 m) para feijão-vagem, de cinco plantas (4,5 m) para abobrinha italiana, cinco plantas (1,5 m) para pimentão, e de quatro plantas (1,2 m) para alface.
590

Algebraic semantics for Nelson?s logic S

Silva, Thiago Nascimento da 25 January 2018 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2018-03-02T23:39:14Z No. of bitstreams: 1 ThiagoNascimentoDaSilva_DISSERT.pdf: 675458 bytes, checksum: 9123812e69a846020d3cd6346e530e1e (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2018-03-13T18:55:45Z (GMT) No. of bitstreams: 1 ThiagoNascimentoDaSilva_DISSERT.pdf: 675458 bytes, checksum: 9123812e69a846020d3cd6346e530e1e (MD5) / Made available in DSpace on 2018-03-13T18:55:45Z (GMT). No. of bitstreams: 1 ThiagoNascimentoDaSilva_DISSERT.pdf: 675458 bytes, checksum: 9123812e69a846020d3cd6346e530e1e (MD5) Previous issue date: 2018-01-25 / Al?m da mais conhecida l?gica de Nelson (?3) e da l?gica paraconsistente de Nelson (?4), David Nelson introduziu no artigo de 1959 "Negation and separation of concepts in constructive systems", com motiva??es de aritm?tica e construtividade, a l?gica que ele chamou de "?". Naquele trabalho, a l?gica ? definida por meio de um c?lculo (que carece crucialmente da regra de contra??o) tendo infinitos esquemas de regras, e nenhuma sem?ntica ? fornecida. Neste trabalho n?s tomamos o fragmento proposicional de ?, mostrando que ele ? algebriz?vel (de fato, implicativo) no sentido de Blok & Pigozzi com respeito a uma classe de reticulados residuados involutivos. Assim, fornecemos a primeira sem?ntica para ? (que chamamos de ?-?lgebras), bem como um c?lculo estilo Hilbert finito equivalente ? apresenta??o de Nelson. Fornecemos um algoritmo para construir ?-?lgebras a partir de ?-?lgebras ou reticulados implicativos e demonstramos alguns resultados sobre a classe de ?lgebras que introduzimos. N?s tamb?m comparamos ? com outras l?gicas da fam?lia de Nelson, a saber, ?3 e ?4. / Besides the better-known Nelson logic (?3) and paraconsistent Nelson logic (?4), in Negation and separation of concepts in constructive systems (1959) David Nelson introduced a logic that he called ?, with motivations of arithmetic and constructibility. The logic was defined by means of a calculus (crucially lacking the contraction rule) having infinitely many rule schemata, and no semantics was provided for it. We look in the present dissertation at the propositional fragment of ?, showing that it is algebraizable (in fact, implicative) in the sense of Blok and Pigozzi with respect to a class of involutive residuated lattices. We thus provide the first known algebraic semantics for ?(we call them of ?-algebras) as well as a finite Hilbert-style calculus equivalent to Nelson?s presentation. We provide an algorithm to make ?-algebras from ?-algebras or implicative lattices and we prove some results about the class of algebras which we have introduced. We also compare ? with other logics of the Nelson family, that is, ?3 and ?4.

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