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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.
1

An investigation into the effects of micronutrients on mood and behaviour in children with attention-deficit/hyperactivity disorder (ADHD) : a pilot study using a single case ABABA design with six-month follow-up.

Gordon, Heather Ann January 2015 (has links)
Attention Deficit Hyperactivity Disorder (ADHD) is one of the most common childhood psychiatric disorders characterised by impairments in attention, hyperactivity and impulsivity. Pharmacological and behavioural treatments have been shown to be effective in treating ADHD. However, with 30% of the population that do not respond or respond poorly to pharmacological treatments, and the growing concerns over the long-term impact stimulants may have on the developing brain, investigation into alternative treatments for ADHD is necessary. More recently research has investigated the effectiveness of EMPowerplus (EMP+), a formula containing a wide range of vitamins and minerals in treating ADHD in adults. The current research examined the effect of EMP+ in treating ADHD in children, following a single-case ABABA design, with a six-month follow-up. Fourteen children between 8 and 12 years of age diagnosed with DSM-IV ADHD took part in the study. Following the baseline assessment, participants took part in an open-label trial of EMP+ for eight weeks, after which EMP+ was withdrawn for four weeks, and then had a final eight weeks on EMP+ and a final four weeks off the micronutrients. A follow-up was conducted approximately six-months after the end of the study. Modified Brinley plots revealed decreased ADHD behaviours, improved mood and improvements in overall functioning during the intervention phases and a reversal in symptoms, decrease in mood and overall functioning during the withdrawal phases. Cohen’s d effect sizes, 95% confidence intervals and t-tests confirmed statistically significant change between the intervention and withdrawal phases. The current study provides further evidence for the potential of micronutrient interventions as a treatment option for children with ADHD. Further research utilising double-blind placebo-controlled studies is warranted.
2

Zinc deficiency in cereals

Imtiaz, Muhammad January 1999 (has links)
No description available.
3

The water-soluble vitamin nutrition of the gilthead seabream (Sparus aurata L.)

Morris, Paul Christopher January 1994 (has links)
Given the paucity of information with regards the micronutrient requirements of the currently expanding number of cultured marine species, a series of investigations was undertaken to examine the water-soluble vitamin nutrition of the gilthead seabream (Sparus aurata L.). A preliminary study identified the qualitative requirement of this species for ascorbic acid, the B complex vitamins and choline for the maintenance of health and optimum productivity. Based on the observations of the preliminary experiment, a study was designed which allowed the development of a semi-purified diet and illustrated the qualitative requirement of the gilthead seabream for thiamin, niacin, riboflavin, pyridoxine and pantothenic acid. Using the semi-purified diet, the requirement for niacin and biotin were also established. As one of the vitamins for which the seabream exhibited a strong requirement, pyridoxine was chosen as the focus for an experiment which evaluated the benefit of the incorporation of this vitamin within a practical diet at levels which exceeded the minimum requirement. Thiamin is a vitamin which is known to exhibit a distinct relationship with carbohydrate metabolism, hence this vitamin was chosen as the focus of an investigation of the potential for the modification of vitamin requirements in response to major nutrient supply. Finally, having illustrated the requirement of gilthead seabream growers for ascorbic acid, an experiment was carried out to evaluate the efficacy of a series of vitamin C derivatives as feed supplements for this species. The current series of investigations has not only served to expand the present knowledge of the vitamin nutrition of the target species but has highlighted the potential for novel and applied research which remains within the field of micronutrients.
4

Micro feeding machines in the dairy industry

Kass, Carl January 1900 (has links)
Master of Agribusiness / Department of Agricultural Economics / Allen M. Featherstone / Micronutrient machines have been used successfully in the beef industry, however, their use was mostly for the addition of antibiotics into the rations. Their use in the dairy industry has been very limited. Feed cost is over 50% of the total cost on a typical dairy farm, thereby creating an area where minor changes in cost per cow can impact the bottom line. Because of the high feed cost on dairy farms, income over feed cost (IOFC) is one of the bench marks as to the overall farm financial health. The feed rations also impact animal health incidences and reproduction efficiencies. Micro machines can add small amounts of a desired nutrient or product, generally less than 56 grams (± 2 oz) into the cattle's daily total mixed rations (TMR). These micronutrients are generally expensive, and their inclusion into the rations of only cows that need that particular micronutrient is one benefit of a micro machine. Micro machines also take out the human error of mixing small accurate amounts and can easily track inventories. Benefits also include the control of on-farm shrink through dust control, and environmental stewardship of resources. Lastly, by creating options to accurately add micronutrients, milk production may be increased and health incidences reduced. The dairy industry is a virtually an untapped field for this technology and this research will explore if there is a benefit from their use. As feeding systems have evolved and milk production has continued to climb, innovative technologies will continue to be implemented. Increased financial pressures will also continue to cause producers to become more efficient with their resources. As production increases in any field, fine tuning of inputs becomes more exact. The rumen inner workings and how feedstuff blends affect rumen micros and the pH levels is an area in which there is much research completed, however, much more is still needed. The addition of micro machines to fine tune rations for dairy farms TMR rations can be a profitable way to manage income over feed cost, not only by saving money spent on micronutrients but by increasing production and reducing herd health incidences.
5

Efeito da modulaÃÃo da glutamina, alanil-glutamina, Ã-caroteno, zinco e do leite de cabra transgÃnico contendo lisozima humana, em cÃlulas epiteliais intestinais sob aÃÃo da Escherichia coli enteroagregativa / Effect of modulation of glutamine, alanyl- glutamine, beta-carotene, zinc, and the milk of transgenic goats containning human lysozyme in intestinal epithelial cells in reponse to infection caused by enteroaggregative Escherichia coli

Eunice Bobà de Carvalho 29 July 2011 (has links)
nÃo hà / As infecÃÃes entÃricas causam cerca de 2,5 milhÃes de mortes ao ano. A EAEC està associada à causa de doenÃas diarrÃicas persistentes. Este estudo analisou in vitro (IEC-6, Caco-2 e HEp-2), o papel dos micronutrientes glutamina, alanil-glutamina, Ã-caroteno, zinco, e dos leites de cabra transgÃnico com lisozima humana e controle nos ensaios de proliferaÃÃo, migraÃÃo, viabilidade, apoptose, necrose celular, adesÃo bacteriana em resposta à infecÃÃo causada pela cepa de EAEC-042 na concentraÃÃo de 2,5 x 105 UFC/mL. A cepa bacteriana de EAEC-042 mostrou reduÃÃo significativa na migraÃÃo (p<0,001) e na viabilidade celular (p<0,001) e esta aumentou a apoptose (p<0,001) e necrose (p<0,001) em resposta a lesÃo ao epitÃlio intestinal. Foi observado que os micronutrientes na presenÃa da bactÃria reduziram significativamente a apoptose e necrose ocasionados por esta, bem como reduziram significativamente a adesÃo bacteriana, alÃm de aumentar a migraÃÃo celular. Os leites controle e transgÃnico apresentaram reduÃÃo significativa da adesÃo bacteriana (p<0,001), independente da presenÃa da camada de gordura, alÃm de reduzirem significativamente a apoptose (p<0,001) e a necrose (p<0,001) ocasionadas pela EAEC-042. A anÃlise qualitativa de aderÃncia celular, considerada padrÃo ouro, mostrou reduÃÃo na aderÃncia bacteriana quando associados aos micronutrientes, comparados ao controle com EAEC-042. Nota-se a quase ausÃncia de aderÃncia em ambos os leites. Este estudo mostra a importÃncia dos micronutrientes e leite de cabra transgÃnico ou nÃo, sobre a proteÃÃo epitelial intestinal nas agressÃes bacterianas. / The enteric infections cause 2.5 million deaths each year. The Enteroaggregative Escherichia coli (EAEC) is associated with persistent cause of diarrheal diseases. This study examined in vitro (IEC-6, Caco-2 and HEp-2 cells) the role of the micronutrients glutamine (Glu), alanyl-glutamine (Ala-Glu), beta-carotene (Ã-Carot), zinc (Zn), and the milk of transgenic goats containning human lysozyme (M-Lyso) and their respective controls (Ctrle) in the following assays: proliferation, migration, viability, apoptosis, cell necrosis, and bacterial adhesion in response to infection caused by the EAEC-042 bacterial strain at a concentration of 2.5 x 105 CFU/mL. The effect of infection by EAEC-042 bacterial strain was evidenced by significant reduction in migration (p <0.001) and cellular viability (p <0.001); also increased apoptosis (p <0.001) and necrosis (p <0.001) in response to damage to the intestinal epithelium. It was observed that the micronutrients in the presence of bacteria significantly reduced apoptosis and necrosis caused by EAEC-042, as well as significantly reduced bacterial adhesion and increases cell migration. The control and transgenic milk abolished bacterial adhesion (p <0.001), independent of milk fat, and significantly reduce apoptosis (p <0.001) and necrosis (p <0.001) caused by EAEC-042. The qualitative analysis of EAEC adherence, considered as gold standard method, showed a reduction in bacterial adherence associated with intervention with micronutrients when compared with the EAEC-042 infection control. In conclusion, our study demonstrates the importance of intervention with micronutrients and milk (transgenic or not) in protecting the intestinal epithelial challenged by bacterial aggression.
6

Interactions between vesicular-arbuscular mycorrhizal fungi, phosphorus, zinc and copper in some crops of semi-arid regions

Natheer, Adel Mohsin January 1991 (has links)
No description available.
7

Wheat response to soil-applied micronutrients and relationships among soil and tissue tests

Majrashi, Mosaed Abdullah January 1900 (has links)
Master of Science / Department of Agronomy / Dorivar A. Ruiz Diaz Suarez / Optimum plant growth under field conditions requires adequate levels of essential nutrients. The objectives of this study were; i) to determine the effect of micronutrient fertilizer application on the concentration of macro and micronutrients in winter wheat plant tissue, and ii) investigate the relationship between soil test parameters and concentration of macro and micronutrients in plant tissue. The study was conducted at six locations in 2012 and 2013 in Kansas. The experimental design consisted of two treatments in a randomized complete block design with three replications. The treatments were applied in field-long strips approximately 364 meters (1,200 feet) long and a minimum of 12 meters (40 feet) wide. The treatments included a fertilized strip and a control strip. The study was initially established to evaluate micronutrients with no P, and K fertilizer applied. The fertilized strips included N, Zn, Mn, Cu (11.2 kgha⁻¹), and B (2.8 kgha⁻¹). Soil samples were collected at planting from points marked with flags located every 30 meters along each strip. Soil samples were collected at the 0 to 15-centimeter depth with 15-20 cores per sample from around each flag in about a five-meter radius. Tissue samples were also collected in a five-meter radius of each flag. Wheat flag leaves were collected at flowering with at least 30 leaves per sample. Soil samples were analyzed for pH, organic matter, soil test phosphorus, potassium, boron, copper, iron, manganese, and zinc. Tissue samples were also analyzed for nitrogen, phosphorus, potassium, sulfur, copper, iron, manganese, and zinc. A complete analysis was done for each location as well as across all study locations using the Proc Mixed procedure in SAS. The micronutrient fertilizer application did not significantly (at P-value level <0.05) influenced tissue N, P, and K but increased S, Zn and Cu tissue concentration across all locations. Manganese tissue concentration was not affected by the application of Mn fertilizer application. Soil test Cu, Fe, and Mn showed good correlation with soil pH and soil test Zn with soil OM. However, only Cu and Mn in the wheat tissue show correlation to soil test for these nutrients. These results suggest that micronutrient concentration in the tissue is governed by multiple soil factors and only partially by DTPA extractable micronutrients. Results from this study also showed that tissue analysis could reflect fertilizer application and availability of micronutrients to the plant. However, there was significant variability in tissue analysis, likely affected by abiotic factors influencing plant nutrient uptake and concentration. While tissue analysis can help as diagnostic tool, producers should be aware of the limitations, and decisions on fertilizer recommendations cannot be based exclusively on tissue test.
8

Dietary micronutrient intake and its relationship with arsenic metabolism in Mexican women.

López-Carrillo, Lizbeth, Gamboa-Loira, Brenda, Becerra, Wendy, Hernández-Alcaraz, César, Hernández-Ramírez, Raúl Ulises, Gandolfi, A Jay, Franco-Marina, Francisco, Cebrián, Mariano E 11 1900 (has links)
Concentrations of inorganic arsenic (iAs) metabolites in urine present intra- and interindividual variations, which are determined not only by the magnitude of exposure to iAs, but also by differences in genetic, environmental and dietary factors.
9

Evaluation of long-term phosphorus fertilizer placement, rate, and source, and research in the U.S. Midwest

Edwards, Cristie LeAnne January 1900 (has links)
Doctor of Philosophy / Department of Agronomy / Dorivar Ruiz Diaz / The appropriate management for phosphorus (P) fertilizer can have significant agronomic, economic, as well as environmental impact. Studies in Kansas have evaluated different management systems to determine best management practices (BMP). The first component of this dissertation is a comprehensive review of tillage system and P fertilizer placement interaction. This review included studies completed in the U.S. Midwest. Results of this review showed greater corn yields with conventional tillage and broadcast applications when soil test P levels (STP) were below 20 mg P kg⁻¹. However, soybean yield was highest in no-till systems with broadcast P fertilizer applications. The second component if this dissertation was a long-term study conducted in Kansas to evaluate the effect of P fertilizer placement on corn and soybean production. Results showed that under strip-tillage, P fertilizer placement significantly affected corn growth, but, seldom resulted in yield response difference among placement methods. Phosphorus application as starter fertilizer at planting showed the most consistent yield response. In addition to the agronomic aspect of this study, the third component of this dissertation consisted of an economic analysis using partial budgets calculated using both fixed and varying prices and costs to compare management practices. With decreased application costs associated with deep banding in strip-tillage system, net returns are greater than broadcast applications. The highest net responses were observed with starter P fertilizer applications. The fourth component of this dissertation included a study evaluating the effects of chelated fertilizer on nutrients, such as P, Fe, Mn, and Zn in soybean. Results from our study showed that both ethylenediamine tetraacetic acid (EDTA)+P and hydroxyethyl ethylenediamine tetraacetic acid (HEDTA)+P resulted in greater concentrations and uptake of Fe and lower Mn uptake in soybean. However, the application of glucoheptonate (GCH)+P had no negative effect on Mn uptake compared to EDTA+P and HEDTA+P. Across locations, EDTA+P and HEDTA+P showed higher yield than GCH+P. The use of long-term studies and comprehensive reviews can provide a unique perspective and better understanding of the most appropriate BMPs for P fertilizer management. Many agronomic and environmental implications of P fertilizer management and the interactions with tillage systems and soils may only become noticeable after multiple years or in a variety of conditions.
10

Manejo fisiológico com base em tratamento de sementes e aplicação de organominerais via foliar para sistemas de alto potencial produtivo de soja / Physiological management based on the seed treatment and organominerals leaf application for the high potential soybean yield system

Soares, Luís Henrique 20 January 2014 (has links)
A produtividade de uma lavoura de soja representa apenas, aproximadamente, 20% do potencial genético. Dessa forma, a exploração das características genéticas tem sido alvo dos pesquisadores para incrementar a produtividade da cultura. Dentro disso, a potencialização fisiológica pela aplicação de estimulantes biológicos, desde a germinação das sementes até a fase reprodutiva da cultura, tem sido uma das principais estratégias adotadas. Visando um aporte à pesquisa nas respostas fisiológicas da cultura, objetivou-se avaliar os efeitos fisiológicos do tratamento de sementes e aplicações foliares de micronutrientes, hormônios e aminoácidos e o quanto estes representam na produção em sistemas de alta produtividade. Foram realizados dois experimentos, sendo um em casa de vegetação (condições parcialmente controladas) (Experimento I) e outro a campo (Experimento II) no Centro Universitário de Patos de Minas (UNIPAM), Patos de Minas-MG, durante o período de janeiro a maio de 2013. Foram realizadas avaliações bioquímicas (atividade das enzimas nitrato redutase, urease, catalase, peroxidase e superóxido dismutase, peroxidação de lipídios e teor de prolina), fisiológicas (fotossíntese liquida) e fenométricas (emergência, índice de velocidade emergência, valor SPAD, taxa de crescimento de raiz, caule e folha, massa de matéria seca total e área foliar), além do número de vagens e da produtividade. Para o primeiro experimento, foram utilizados quatro tratamentos de sementes (controle; micronutrientes - Zn, Mn, B, Mo, Ni e Co; hormônios - ácido indol butírico, ácido giberélico e cinetina; e aminoácidos - ácido glutâmico, arginina, glicina, metionina e cisteína) com seis repetições em delineamento inteiramente casualizado. No segundo experimento, foram utilizados seis tratamentos de semente (controle; micronutrientes; hormônios; aminoácidos; micronutrientes e hormônios; e micronutrientes e aminoácidos) em dois sistemas de manejo: sistema convencional e sistema para produtividade potencial, com utilização de redutor de crescimento e aplicações periódicas de organominerais via foliar (doze tratamentos com quatro repetições em delineamento em blocos ao acaso). Com base nos resultados obtidos, conclui-se que: (i) o tratamento de sementes com micronutrientes potencializa a assimilação de nitrogênio e a fotossíntese líquida, e incrementa o teor de clorofila (valor Spad) e taxa de crescimento de plantas de soja; (ii) a utilização de aminoácidos ou hormônios reduz o nível de estresse das plantas durante o período inicial de crescimento e aumenta a produção de massa de matéria seca; (iii) o tratamento de sementes com micronutrientes, hormônios ou aminoácidos incrementa o teor de clorofila (valor Spad), (iv) o sistema para produtividade potencial potencializa a atividade fisiológica das plantas e, consequentemente, aumenta o número de vagens por planta e a produtividade em relação ao sistema convencional; (v) em sistema para produtividade potencial, o tratamento de sementes com micronutrientes é o mais responsivo (aumento de produtividade em 18,5%), e (vi) no sistema convencional, o tratamento com micronutrientes e aminoácidos aumenta a produtividade em 80%. / The actual soybean productivity represents about 20% of genetic potential. Thus, the exploitation of genetic characteristics has been targeted by researchers to increase crop yield. In addition, the physiological potentiation by applying biological stimulants, from seed germination to the reproductive stage of the crop, has been one of the main strategies adopted. Seeking a contribution to research on the physiological responses of soybean crop, aimed to evaluate the physiological effects of seed treatment and foliar applications of micronutrients, amino acids and hormones and how they represent in the production of the high productivity systems. Two experiments were carried out, one in the greenhouse (partially controlled conditions) (Experiment I) and other in the field (Experiment II) at the University Center of \"Patos de Minas\" (UNIPAM), \"Patos de Minas\", \"Minas Gerais\" State, Brazil, during the period of January to May 2013. Biochemical assessments (nitrate reductase, urease, catalase, peroxidase and superoxide dismutase activities, lipid peroxidation and proline content), physiological (net photosynthesis) and fenometric evaluations (emergency, emergency speed index, Spad value, leaf area, growth rate of root, stem, leaf, total dry matter and leaf area), beyond of the number of pods per plant and productivity. For the first experiment, four seed treatments (control; micronutrients - Zn, Mn, B, Mo, Ni and Co; hormones - indol butyric acid, gibberellic acid and kinetin; and amino acids - glutamic acid, arginine, glycine, methionine and cysteine) with six replications were carried out in a completely randomized design. For the second experiment, six seed treatments (control; micronutrients; hormones; amino acids; micronutrients and hormones; and micronutrients and amino acids) were used in two management systems: conventional system and system for potential productivity, using growth reducer and periodic leaf applications of biological stimulants (twelve treatments with four replications in a randomized blocks design). Based on obtained results, it is concluded that: (i) the seed treatment with micronutrients potentiates the nitrogen assimilation and net photosynthesis, and increases the chlorophyll content (Spad value) and soybean plant growth rate; (ii) the use of amino acids or hormones reduces plant stress level during the initial period of plant growth and increase the dry matter production; (iii) the seed treatment with micronutrients, hormones or amino acids increases chlorophyll content (Spad value); (iv) the system for potential productivity potentiates the physiological activity of plants and, consequently, increases the number of pods per plant and productivity when compared to conventional system; (v) under system for potential productivity, the seed treatment with micronutrients is the most responsive (increases productivity in 18.5%); and (vi) under conventional system, the treatment with micronutrients and amino acids increases the productivity in 80%.

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