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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

Silício como mitigador de deficiência e toxicidade de boro na cultura do algodão cultivado em solução nutritiva / Silicon as a deficiency mitigator and boron toxicity in the culture of cotton cultivated in nutritive solution

Souza Junior, Jonas Pereira de [UNESP] 28 February 2018 (has links)
Submitted by Jonas Pereira de Souza Júnior (jonas.psj@hotmail.com) on 2018-04-23T20:57:44Z No. of bitstreams: 1 dissertação final.pdf: 1689877 bytes, checksum: db5dec7519f11508f805cbffc672e4fd (MD5) / Approved for entry into archive by Alexandra Maria Donadon Lusser Segali null (alexmar@fcav.unesp.br) on 2018-04-25T12:46:15Z (GMT) No. of bitstreams: 1 souzajunior_jps_me_jabo.pdf: 1689877 bytes, checksum: db5dec7519f11508f805cbffc672e4fd (MD5) / Made available in DSpace on 2018-04-25T12:46:15Z (GMT). No. of bitstreams: 1 souzajunior_jps_me_jabo.pdf: 1689877 bytes, checksum: db5dec7519f11508f805cbffc672e4fd (MD5) Previous issue date: 2018-02-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A deficiência de boro é um fator limitante na produção do algodoeiro, mas o excesso pode induzir à toxicidade. Nas duas desordens nutricionais de boro, o acréscimo de silício, via foliar ou radicular, pode aliviar esses efeitos, mas essas informações não são conhecidas nas plantas de algodão. Objetivou-se (a) inicialmente, verificar a fonte e a concentração de Si aplicada via foliar que resulta em maior acúmulo do elemento nas plantas de algodão; (b) definir a concentração crítica do boro na solução nutritiva que induz à deficiência e à toxicidade do micronutriente nas plantas de algodão, e (c) verificar o efeito do silício, aplicado via foliar e radicular, como agente mitigador dos efeitos deletérios da deficiência e da toxicidade de boro no algodoeiro. Foram desenvolvidos três experimentos em plantas de algodão transgênico cultivados em sistema semi-hidropônico em casa de vegetação. O primeiro experimento foi com concentrações de Si via foliar em diferentes fontes do elemento. O segundo experimento foi com concentrações de B na solução nutritiva. Com os resultados destes experimentos, obtiveram-se a concentração foliar de Si e a fonte mais adequada, e a concentração de B na solução nutritiva, que induz a suficiência, deficiência e toxicidade. Diante destes resultados, realizou-se o terceiro experimento, onde foram avaliados Si aplicado via foliar e radicular, e o controle (sem Si) em plantas de algodão sob deficiência, suficiência e toxicidade de B. A aplicação foliar de Si é viável agronomicamente para o algodoeiro, pois incrementou o acúmulo de Si, o teor de clorofila e a eficiência quântica do fosossistema II, favorecendo a produção de matéria seca, destacando-se o Si aplicado na forma de silicato de sódio e potássio estabilizado com sorbiol, na concentração de 0,8 g L-1 de Si. O nível crítico de B na solução nutritiva por deficiência e toxicidade, associado à diminuição de 25% da produção de massa seca de plantas de algodão, foi 33,7 e 130,5 µmol L-1 de B, respectivamente. O silício mitiga desordem nutricional de boro em algodoeiro, destacando aplicação foliar e radicular para aliviar os efeitos deletérios de deficiência e toxicidade de B, respectivamente. / Boron deficiency is a limiting factor for cotton production, but boron excess may induce toxicity. In the two nutritional disorders of boron, the addition of silicon by leaf or root application can alleviate these effects but this information is unknown in cotton plants. The objective of this study was to (a) initially verify the source and concentration of Si applied in the leaf that results in greater accumulation of the element in the cotton plants; (b) define the critical concentration of boron in the nutrient solution that induces the deficiency and toxicity of the micronutrient, and (c) to verify the effect of silicon, applied by leaf and root, as a mitigating agent of the deleterious effects of boron deficiency and toxicity in cotton. Three experiments were carried out on cotton plants cultivated in a soilless growing system. The first experiment was with concentrations of Si by leaf application with different sources of the element. The second experiment was with concentrations of B in the nutrient solution. With the results of these experiments, we got the more adequate Si foliar source and concentration; and the concentration of B in nutrition solution that induces to sufficiency, deficiency and toxicity. The third experiment was done to verify the effects of apply silicon by leaf and root and control (without Si) in cotton plants under deficiency, sufficiency and toxicity of B. The application of Si is viable for cotton, since it increased the accumulation of Si, the chlorophyll content and the quantum efficiency of the photosystem II, favoring the dry matter production, emphasizing Si applied in the form of sodium and potassium silicate stabilized with sorbitol at the concentration of 0,8 g L-1 of Si. The critical level of B in the nutrient solution due to deficiency and toxicity, associated with a 25% decrease in dry matter yield of cotton plants, was 33.7 and 130.5 µmol L-1 of B, respectively. Silicon mitigates nutritional disorder of boron in cotton highlighting leaf and root application to alleviate the deleterious effects of B deficiency and toxicity, respectively.
82

Efeito do B, Mo e Zn no conteúdo de proteínas, carboidratos e aminoácidos livres em grãos e sementes de ervilha (Pisum sativum L.) /

Nogueira, Débora Cristiane. January 2007 (has links)
Orientador: Kuniko Iwamoto Haga / Banca: Marco Eustáquio de Sá / Banca: Juliana Domingues Lima / Resumo: A região de cerrado tem como principais fatores limitantes da produção agrícola as condições climáticas e solos com baixa fertilidade natural. Neste sentido, são importantes estudos para entender os fatores que contribuem para o desempenho das culturas em condições de cerrado, como por exemplo a ervilha. O objetivo foi avaliar o efeito da aplicação foliar do boro, molibdênio e zinco na qualidade de grãos de ervilha e produtividade. A ervilha utilizada foi a variedade Utrillo, cujo cultivo foi realizado na área experimental da Fazenda de Ensino Pesquisa e Extensão-FE-UNESP-Campus de Ilha Solteira. Os tratamentos constaram das combinações entre aplicação de boro, molibdênio e zinco, (Testemunha, B, Mo, Zn, B+Mo, B+Zn, Mo+Zn, B+Mo+Zn). O Mo foi aplicado via foliar aos 20 dias após a emergência das plantas (DAE). O B e o Zn foram aplicados também via foliar aos 30 DAE. O delineamento experimental foi em blocos casualizados com quatro repetições, as médias comparadas pelo teste de Duncan a 5% de significância. Analisou-se produtividade e o conteúdo de nutrientes, de amido, de aminoácidos, de proteinas nos grãos e sementes e a qualidade fisiológica das sementes. Os resultados indicaram que os tratamentos alteram significativamente apenas o conteúdo de magnésio e de cobre nos grãos. Os demais fatores estudados não se alteraram devido ao tratamento imposto à cultura. / Abstract: Some times the crops yield in the cerrado area is limited by weather conditions and the soil with a low fertility. The studies in this direction are important to understand the factors that contribute for the performance of the cultures in the cerrado conditions, for example pea's crop. The objective was to evaluate the effect of the foliar application of boron, molybdenum and zinc on the quality of pea grains and grain yield. For experiment were used seeds of pea, cv. Utrillo, cultivated in the experimental area of the Farm of the Teach Research and Extension-FE-UNESP- Campus de Ilha Solteira". The eight treatments consisted of the combinations among application of boron, molybdenum and zinc, (Control, B, Mo, Zn, B+Mo, B+Zn, Mo+Zn, B+Mo+Zn). 20 days after emergency (DAE) was applied Mo by foliar. B and Zn were applied by foliar at 30 DAE. The experimental delineation used was the randomized blocks with four repetitions; the averages had been compared by Duncan test at 5% of significance. It was analyzed the grain nutrient content, grain yield, starch, aminoacids and proteins content in the grains and seeds and physiological seed quality. The results had indicated that the treatments modify significantly only to the copper and magnesium content in the grains. The other studied factors they didn't alter due to the treatment imposed to the culture. / Mestre
83

Bactérias diazotróficas e adubação molíbdica na contribuição da fixação biológica de N2 em cana planta

SILVA, Magda Aline da 29 February 2016 (has links)
Submitted by Mario BC (mario@bc.ufrpe.br) on 2016-06-28T13:18:04Z No. of bitstreams: 1 Magda Aline da Silva.pdf: 1179000 bytes, checksum: 387c2eca36fb2ddb9ef9a27616f0d867 (MD5) / Made available in DSpace on 2016-06-28T13:18:04Z (GMT). No. of bitstreams: 1 Magda Aline da Silva.pdf: 1179000 bytes, checksum: 387c2eca36fb2ddb9ef9a27616f0d867 (MD5) Previous issue date: 2016-02-29 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The Biological Nitrogen Fixation (BNF) realized by diazotrophics bacterias in sugarcane has variable and somewhat inconsistent results, which has limited the use of inoculants. The BNF is catalyzed by the enzyme nitrogenase, which has in its constitution the MoFe- protein component. Thus, the use of molybdenum (Mo) in plants inoculated with atmospheric nitrogen N2 fixing bacteria can be used as an alternative to elevate the increments of BNF in non-leguminous crops such as sugarcane. The method of the 15N isotope dilution currently employed to quantify the BNF sugarcane, used as reference plant species with growth physiology and running N distinct absorption, which increases the variation and reduces the reliability of the results. In the context, two studies were carried out, the first one was to evaluate the main specimens of reference plants in the quantification of FBN for sugarcane and the second study was to evaluate the contribution of molybdenum fertilizer in increasing BNF by bacteria diazotrophic inoculated in the plant cane. The interaction of Mo in FBN was evaluated by the nitrogenase enzyme activity and the method of isotopic dilution from soil enrichment with 2% of 15N atoms, using sugarcane fertilized with nitrogen as the reference plant. The experiment was conducted in pots with a sandy soil. In the first experiment, the species most commonly used as a reference plant was compared to sugarcane fertilized and non-fertilized with N, using a completely randomized design, with four repetitions. The second experiment evaluated the interaction between nitrogen fertilization, Mo and inoculants containing diazotrophs using factorial arrangement of 2 x 2 x 3, statistical design of randomized blocks with four repetitions. The sugarcane fertilized with N had the lowest dilution of 15N, indicating restriction of FBN and its recommendation as plant control. The guinea grass (Panicum maximum L.) and purple nutsedge (Cyperus rotundus L.) showed high FBN, which makes them not recommended as species control to quantify the N2 fixed by the method of isotopic dilution of 15N. The use of micronutrient Mo interacted positively with the diazotrophs inoculated in the growth and development of plant cane, as well as in the BNF. However, the increases were not found sufficient to meet the total requirement of N, showing the importance of nitrogen fertilizer to plant sugarcane. / A fixação biológica do nitrogênio (FBN) por bactérias diazotróficas na cana-de-açúcar apresenta resultados variáveis e pouco consistentes, o que tem limitado o uso dos inoculantes. A FBN é catalisada pela enzima nitrogenase, que possui na sua constituição o componente MoFe-proteína. Assim, a utilização do molibdênio (Mo) em plantas inoculadas com bactérias diazotróficas fixadoras do N2 atmosférico pode ser utilizado como alternativa para elevar os incrementos da FBN nas culturas não leguminosas como a cana-de-açúcar. O método da diluição isotópica do 15N atualmente empregado para quantificar a FBN na cana-de-açúcar, utiliza como planta referência espécies com fisiologia de crescimento e marcha de absorção do N distintas, o que aumenta a variação e reduz a confiabilidade dos resultados. Diante do contexto, realizaram-se dois estudos, o primeiro para avaliar os principais espécimes de plantas referência na quantificação da FBN para a cana-de-açúcar e o segundo estudo teve como objetivo avaliar a contribuição da adubação molíbdica no incremento da FBN por bactérias diazotróficas inoculadas na cana planta. A interação do Mo na FBN foi avaliada pela atividade da enzima nitrogenase e pelo método da diluição isotópica a partir do enriquecimento do solo com 2% de átomos de 15N, utilizando a cana-de-açúcar adubada com nitrogênio como planta referência. O experimento foi conduzido em vasos, com solo de textura arenosa. No primeiro experimento, as espécies mais utilizadas como planta referência foi comparada com a cana-de-açúcar adubada e não adubada com N, utilizando o delineamento inteiramente casualizado, com 4 repetições. No segundo experimento, avaliou-se a interação entre adubação nitrogenada, Mo e inoculantes contendo bactérias diazotróficas utilizando o arranjo fatorial de 2 x 2 x 3, em delineamento estatístico de blocos casualizados, com 4 repetições. A cana-de-açúcar adubada com N apresentou a menor diluição do 15N, indicando restrição da FBN e sua recomendação como planta controle. O capim colonião (Panicum maximum L.) e a tiririca (Cyperus rotundus L.) apresentaram elevada FBN, o que as torna não recomendáveis como espécies controle para quantificar o N2 fixado pelo método da diluição isotópica do 15N. O uso do micronutriente Mo interagiu positivamente com as bactérias diazotróficas inoculadas no crescimento e desenvolvimento da cana planta, bem como na FBN. Entretanto, os incrementos encontrados não foram suficientes para suprir a necessidade total do N, mostrando a importância da adubação nitrogenada para cana planta.
84

Tratamento de sementes de milho com zinco: avaliações do potencial fisiológico das sementes, do rendimento e do valor nutricional dos grãos / Treatment of corn seed with zinc: evaluations of the physiological potential of seeds, yield and nutritional value of the grains

Marcella Nunes de Freitas 06 February 2017 (has links)
O Zn é essencial para o metabolismo de plantas, animais e do ser humano. Existe a necessidade de buscar soluções para a baixa disponibilidade de Zn, frequente em solos do Brasil e do mundo, e de melhorar o valor nutricional dos grãos de cereais com este nutriente. O tratamento de sementes pode apresentar-se como uma importante técnica para o fornecimento de Zn na cultura do milho (Zea mays L.). Este estudo foi dividido em quatro capítulos, no primeiro, objetivou-se avaliar o potencial fisiológico de sementes de milho tratadas com Zn durante o armazenamento; no segundo, avaliou-se a distribuição do Zn em sementes tratadas durante o armazenamento das sementes por 6 e 12 meses, bem como a absorção do Zn por plântulas; no terceiro capítulo, foram avaliados os reflexos do tratamento de sementes com Zn sobre a produção de biomassa, rendimento e valor nutricional dos grãos e, por fim, no quarto capítulo, determinou-se, pelo uso da marcação do óxido de Zn com o nuclídeo 68Zn, a absorção do Zn pela planta, utilizando o método isotópico. Os resultados demonstram que o tratamento de sementes pode incrementar o vigor das plântulas provenientes de sementes com baixo potencial fisiológico; entretanto, em condições de armazenamento com temperatura e umidade relativa do ar não controladas, plântulas provenientes de sementes maiores tratadas, armazenadas por 12 meses nessas condições, podem apresentar fitotoxicidade, em função do tratamento. O Zn disponibilizado em revestimento, durante o armazenamento das sementes tratadas por 6 e 12 meses, sob condições não controladas, pode penetrar no pericarpo das sementes e encontrar-se acumulado em pontos específicos da semente. O ponto de maior acúmulo de Zn nas sementes é o embrião, acima da camada negra. Quanto à absorção do Zn disponibilizado via tratamento por plântulas, após horas 72 horas de as sementes terem sido colocadas para germinar, são visíveis os pontos de acúmulo do Zn na raiz primária, evidenciando que tecidos meristemáticos possuem alta demanda pelo elemento. O tratamento de sementes com Zn não propiciou aumento da biomassa da planta, rendimento dos grãos, acúmulo de Zn nas plantas e concentração de Zn nos grãos. Apesar desse resultado, o Zn disponibilizado via tratamento de sementes contribui de forma significativa para a nutrição das plantas de milho, conforme se avaliou por meio da marcação isotópica. / Zn is essential to the metabolism of plants, animals and human being. There is the need for solutions regarding the low availability of Zn, frequent on soils of Brazil and of the world, and for improving the nutritional value of grains with this nutrient. Treatment of seeds may present as an important technique for the provision of Zn in the corn culture (Zea mays L.). This study is organized in four chapters, in the first one, the objective is to determine the physiological potential of corn seeds treated with Zn during storage; in the second, the Zn distribution in seeds treated during storage for 6 and 12 months was analyzed, as well as the Zn absorption by plantules; in the third chapter, reflexes of the treatment of seeds with Zn over the production of biomass were evaluated and, lastly, the fourth chapter aims at determining the absorption of Zn by the plant, using the isotope method and marking zinc oxide with the 68Zn nuclide. Results showed that the treatment of the seeds may improve the vigor of plantules coming from seeds with low physiological potential; however, treated plantules coming from bigger seeds, stored for 12 months in uncontrolled conditions of temperature and relative humidity may present phytotoxicity because of the treatment. Zn made available in form of coating, during storage of seeds treated for 6 and 12 months, in uncontrolled conditions, may penetrate the pericarp of seeds and accumulate on specific spots. The biggest Zn accumulation spot Zn in seeds is the embryo, above the black layer. Regarding the absorption of Zn by the plantules made available via treatment, after 72 hours seeds germinated, accumulation spots of Zn in the primary root are visible, showing that the meristematic tissues have a high demand for the element. The treatment of seeds with Zn did not favor increase in the biomass of the plant, grain yield, accumulation of Zn in plants and concentration of Zn in grains. Despite this result, Zn made available via treatment of seeds contributes significantly for the nutrition of corn plants, as evaluated using isotope marking.
85

Translocação de molibdênio para plântulas de feijoeiro na aplicação de sementes / Translocation of molybdenum for bean seedlings in the application of seed

Carvalho, Ireni Leitzke 22 December 2010 (has links)
Made available in DSpace on 2014-08-20T13:44:47Z (GMT). No. of bitstreams: 1 dissertacao_ireni_leitzke_carvalho.pdf: 351642 bytes, checksum: 3da57c72c0a5bd61aaff28a3cf8654d0 (MD5) Previous issue date: 2010-12-22 / Molybdenum is essential for the bean crop, it influences the metabolism of fixing atmospheric nitrogen, it becomes an indispensable micronutrient for the development of culture. The aim of this study was to evaluate the effect of molybdenum seed treatment on physiological quality of bean seeds and translocation of this chemical element in different stages of seedling development. The treatments were a combination of seed molybdenum, equivalent to 0; 21,5; 43; 64,5 and 86 g.100kg-1. It was used seeds of bean cultivars Expedite and Valente. The physiological quality of seeds was evaluated by germination, first count germination, cold test, accelerated aging, field emergence, emergence rate index, length and dry weight of shoot and root. For the determination of molybdenum translocated, the seeds were sown in trays using washed sand as substrate. At 8, 10, 12 and 14 days after sowing was conducted on the sampling of seedlings. We determined the mass and the molybdenum content of the shoot, by UV-Visible spectrophotometer at 405 nm. The data revealed that there is possibility of applying molybdenum in bean, by seed treatment, in doses of up to 40 g ha-1, without causing damage to the quality and physiological translocated molybdenum content increases linearly with the applied doses. / O molibdênio, essencial para a cultura do feijoeiro, influencia o metabolismo de fixação do nitrogênio atmosférico, tornando-se um micronutriente indispensável ao desenvolvimento da cultura. O objetivo deste trabalho foi avaliar o efeito da aplicação de molibdênio via tratamento de sementes sobre qualidade fisiológica de sementes de feijão e a translocação desse elemento químico em diferentes estádios de desenvolvimento da plântula. Os tratamentos foram constituídos pela aplicação de molibdênio via sementes, equivalentes a 0; 21,5; 43; 64,5 e 86 g.100kg-1. Foram utilizadas sementes de feijão, cultivares Expedito e Valente. A qualidade fisiológica das sementes foi avaliada pelos testes de germinação, primeira contagem da germinação, frio, envelhecimento acelerado, emergência em campo, índice de velocidade de emergência, comprimento e massa de matéria seca de parte aérea e de raiz. Para a determinação do teor de molibdênio, realizou-se a semeadura em bandejas utilizando substrato areia lavada. Aos 8, 10, 12 e 14 dias após a semeadura realizou-se a coleta das plântulas. Determinaram-se a massa e o teor de molibdênio da parte aérea, em espectrofotômetro UV-Visivel a 405 nm. Os dados obtidos permitem afirmar que há possibilidade de aplicar molibdênio em feijão, via tratamento de sementes, em doses de até 86 g.100kg-1, sem causar prejuízos à qualidade fisiológica e o teor de molibdênio nas plântulas aumenta linearmente com as doses aplicadas.
86

Association between postnatal maternal nutritional status, maternal HIV disease progression and infant feeding practices in 4 clinics in Pretoria, South Africa

Matji, J.N. (Joan Nteboheleng) 08 March 2010 (has links)
Introduction A group of 317 HIV-1 infected pregnant women and 53 postpartum HIV-negative women were recruited for a two-year prospective descriptive study of psychosocial and other determinants of antenatally planned and actual postnatal feeding, associations between maternal status and infant feeding practices, and health outcomes. Methods The subjects were interviewed periodically for 2 years using structured research instruments. Anthropometric measurements, biomarkers of nutritional status and measurements of pysychosocial wellbeing were obtained from the mothers. Data was collected on infant feeding and outcomes for the babies. Results At recruitment, 74% of mothers planned to formula-feed. Significant differences between these women and those who planned to breastfeed emerged. After delivery, 25% of the women who antenatally planned to formula-feed changed their minds and actually breastfed. Conversely, half of the women who antenatally planned to breastfeed actually formula-fed. Some significant reasons emerged for these feeding changes. Most mothers were well-nourished or overweight. Breastfeeding mothers lost little weight between six weeks and six months after delivery. At the end of follow-up, 65% were obese. While there were differences between HIV-infected and uninfected women in respect of micronutrients, no deficiencies were observed. Vitamin A and selenium concentrations were higher in the HIV-infected women than uninfected women at six weeks. There were no significant micronutrient changes over time. Most mothers maintained an adequate immune status with only slow deterioration of CD4 counts. At two years postpartum, 60% had a CD4 cell count greater than 500cells/mm³, and only about 8% less than 200/mm3. HIV transmission was 15% by 24 months of follow-up. Among the 65 ever breastfed children, 16 (24.6%) were HIV-infected compared to 12.8% of never breastfed children. Most children were growing normally, suggesting that, overall, maternal HIV status did not interfere with feeding ability. Eight mothers (3%) and 33 children (11%) died. Only 12 of 33 children who had died had a positive HIV-PCR. By 2 years, 78% surviving HIV-infected children had been initiated onto ARV therapy. Maternal adherence to HAART was poor. Conclusion HIV and infant feeding counselling is inadequate in the routine PMTCT programme, with stigma and lack of disclosure continuing as major barriers to appropriate care. Whilst maternal obesity was common, most children were growing normally. Weaknesses in routine PMTCT services were identified, and compliance with HAART was poor. / Thesis (PhD)--University of Pretoria, 2010. / Paediatrics and Child Health / unrestricted
87

Adubação com micronutrientes no plantio da cultura da cana-de-açúcar /

Adorna, Jaqueline Cristiane, 1980- January 2011 (has links)
Orientador: Carlos Alexandre Costa Crusciol / Banca: Dirceu Maximino Fernandes / Banca: Rafaella Rossetto / Resumo: Com relação ao aumento da área cultivada, a cana-de-açúcar disseminou-se em vários estados brasileiros, tendo se estabelecido sobre os mais diferentes tipos de solos, muitas vezes com características bastante distintas dos padrões ideais para produção. A cana-de-açúcar, assim como as demais plantas superiores necessita para o seu desenvolvimento dos macro e micronutrientes. Apesar de a cana-de-açúcar ser uma das culturas mais pesquisadas no Brasil, ainda existe pouca informação relativa ao uso de micronutrientes. Diante da necessidade dessas informações, o objetivo deste trabalho foi avaliar a resposta da cana-de-açúcar à aplicação de micronutrientes em diferentes condições de cultivo. O projeto de pesquisa foi constituído de três experimentos conduzidos em condições de cana planta, em solos de textura argilosa (Latossolo Vermelho), arenosa (Neossolo Quartzarênico) e franco-arenosa (Argissolo Vermelho). Os experimentos foram instalados em áreas pertencentes à Usina da Barra localizada no município de Barra Bonita-SP, na safra 2008/2009 (Latossolo Vermelho e Neossolo Quartzarênico), e na Usina Cerradinho no município de Catanduva - SP conduzido na safra 2009/2010 (Argissolo Vermelho). O delineamento experimental foi em blocos casualizados, com quatro repetições, no esquema fatorial 8 x 2, sendo a combinação de micronutrientes (1 - sem aplicação/testemunha, 2 - adição de Zn, 3 - adição de Cu , 4 - adição de Mn, 5 - adição de Fe, 6 - adição de B, 7 - adição de Mo, 8 - adição de Zn, Cu, Mn, Fe, B e Mo) com torta de filtro (0 e 30 Mg ha-1 de torta de filtro) no sulco de plantio. Mediante os resultados constatou-se que a aplicação de Zn, B, Cu, Mn, Fe e Mo no sulco de plantio sem torta de filtro não alterou os teores foliares de macro e micronutrientes e as variáveis tecnológicas Pol, Fibra, Pureza e ATR nos três tipos de solos... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Concerning the increase in cultivated area, the sugarcane has spread in several Brazilian states, having settled on the most different types of soils, often with quite different characteristics of the ideal standards for production. The sugarcane, like other higher plants need for their development of macro and micronutrients. Although sugarcane is one of the most researched crops in Brazil, there is still little information concerning the use of micronutrients. Faced with the need for such information, the purpose of this study was to evaluate the response of sugarcane to the application of micronutrients in different culture conditions. The research project was conducted three experiments carried out in the sugarcane plant, in clayey soils (Oxisol), sandy (Entisol) and sandy loam (Ultisol). The experiments were conducted in areas belonging to the Da Barra located in Barra Bonita-SP, in the 2008/2009 harvest (Oxisol and Entisol), and the plant mill Cerradinho in Catanduva - SP conducted in the 2009/2010 harvest (Ultisol). The experimental design was randomized blocks with four replications and 8 x 2 factorial, with the combination of micronutrients (1 - no application / control, 2 - addition of Zn, 3 - addition of Cu, 4 - addition of Mn 5 - addition of Fe, 6 - B addition, 7 - addition of Mo, 8 - Addition of Zn, Cu, Mn, Fe, B and Mo) and filter cake (0 and 30 Mg ha-1 of filter cake) at planting. From the results it was found that application of Zn, B, Cu, Mn, Fe and Mo in the furrow without filter cake did not affect foliar concentrations of macro and micronutrients and technological parameters Pol, Fiber, Purity and ATR in three soil types evaluated. The application of filter cake increased the concentrations of B to the sufficiency range in Entisol. The filter cake increased the number of tillers and plant height in the Ultisol, and the number of tillers, number of stems and yield... (Complete abstract click electronic access below) / Mestre
88

Multi-Assay Nutritional Metabolomics Profiling of Low Vitamin A Status Versus Adequacy Is Characterized by Reduced Plasma Lipid Mediators Among Lactating Women in the Philippines: A Pilot Study

Johnson, Catherine M. 01 August 2021 (has links) (PDF)
Background: A significant portion of lactating women in less developed countries have vitamin A (VA) deficiency. Lactation has substantial effects on a mother’s metabolism and VA is known to be needed in multiple biological processes, including growth, vision, immunity, and reproduction. Objective: The objective of this pilot study was to utilize metabolomics profiling to conduct a broad, exploratory assessment of differences in plasma metabolites associated with low VA status versus adequacy in lactating women. Methods: Plasma samples from lactating women who participated in a survey in Samar, Philippines, were selected from a cross-sectional study based on plasma retinol concentrations indicating low (VA-; n=5) or adequate (VA+; n=5) VA status (plasma retinol <0.7 or >1.05 µmol/L). The plasma results collected from six metabolomics assays (oxylipins, endocannabinoids, bile acids, primary metabolomics, aminomics, and lipidomics) were compared by group, using liquid chromatography mass spectrometry. Results: Twenty-eight metabolites were significantly different in the VA- versus VA+ status, with 24 being lipid mediators (p<0.05). The lipid mediators demonstrated lower concentrations of the arachidonic acid- and eicosapentaenoic acid-derived oxylipins, as well as lysophospholipids and sphingolipids, in the VA- group (p<0.05). Chemical similarity enrichment analysis identified HETEs, HEPEs, and DiHETEs as significantly different oxylipin clusters (p<0.0001, false discovery rate (FDR) p<0.0001), as well as sphingomyelins, saturated lysophosphatidylcholines, phosphatidylcholines, and phosphatidylethanolamines (p<0.001, FDR p<0.01). Conclusions: The multi-assay nutritional metabolomics profiling of low VA status compared with adequacy in lactating women demonstrated reduced lipid mediator concentrations. Future studies with stronger study designs and a large and more diverse population are needed to validate these preliminary results.
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Essays in the Non-Separability between Environmental Resources and Human Nutrition, and the Role of Markets in Mitigating the Linkage: Evidence from Malawi and Nepal

Kim, Kichan January 2021 (has links)
No description available.
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Influences of Select Dietary Components on Bone Volumetric Density, Bone Geometry and Indices of Bone Strength in Young Girls

Laudermilk, Monica J. January 2011 (has links)
Osteoporosis, a major public health problem, likely has its origins in childhood. During periods of rapid skeletal growth, diet may influence accrual of bone mineral density (BMD) and adult bone health. This study used novel approaches in bone imaging to further characterize optimal skeletal development and enhance our understanding of key dietary components that influence attainment of peak bone mass (PBM) and contribute to determinants of peak bone strength in peri-pubertal females. The use of a validated food-frequency questionnaire (FFQ) enabled the influence of usual dietary intake on bone parameters to be examined.This study examined the relationship of dietary intake of micronutrients and bone macro-architectural structure in peri-pubertal girls. This study suggested that vitamin C and zinc intake are associated with objective measures of bone status in 4th, but not 6th grade girls. This indicates potential differences in micronutrient and bone associations at various age-associated stages of bone maturation.The impact of dietary fat on peri-pubertal skeletal growth is not well characterized. This study examined relationships of select dietary fatty acid (FA) intakes and measures of bone status in peri-pubertal girls. This study suggested that MUFA, total PUFA, n-6 and linoleic acid (LA) are inversely associated with bone status prior to menarche, but composition of dietary fat may be more important during the early-pubertal years. Decreased intakes of n-6 PUFA may benefit bone health in young girls.The impact of a dietary protein on volumetric bone mineral density (vBMD), bone mineral content (BMC) and bone strength throughout maturation remains controversial. Given evidence of both anabolic and catabolic affects of protein on bone health, this study examined relations of dietary protein from different sources with bone parameters in peri-pubertal girls. This study showed that dietary protein intake is related to higher trabecular but not cortical vBMD, BMC and BSI, and accounts for 2-4% of their variability in peri-pubertal girls. The relationship seems to vary by the source of dietary protein and calcium intake. However, a negative impact of animal protein on bone health is not supported. Large scale observational and intervention studies are needed to establish causality.

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