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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.
361

The tuck shop purchasing practices of grade 4 learners at selected primary schools in Pietermar[it]zburg, South Africa.

Wiles, Nicola Laurelle. 12 November 2013 (has links)
Aim: To determine whether the tuck shop purchasing habits of Grade 4 learners were contributing towards the development of childhood overweight and obesity. Objectives: To assess the nutritional quality of the food and beverages available for learners to purchase; items regularly purchased from the tuck shop as well as factors influencing the learner’s decision to purchase these items; the anthropometric and socio-demographic characteristics of grade 4 learners as well as their nutrition knowledge related to the tuck shop items purchased. Method: A survey administered to 11 tuck shop managers, a questionnaire administered to 311 Grade 4 learners and two single-sex focus groups of 5 learners each were conducted. Results: Fifty six percent of the sample were female (n=173) and 44% were male (n=138). Twenty seven percent of the study sample was overweight (n = 83) and 27% were obese (n = 85). Eighty six percent of learners (n = 266) claimed to buy from their school tuck shop. Twenty two percent of learners purchased from their tuck shop at least three times per week (n =58). Learners who purchased from the tuck shop had a significantly higher BMI than those who did not (p = 0.020). Learners who purchased from the tuck shop spent on average R8,38 per day with a minimum of R1 and a maximum of R40 (standard deviation R5.39). The most popular reasons for visiting the tuck shop included “this is my favourite thing to eat or drink” (66.5%, n = 177) and “I only have enough money to buy this item” (47.0%, n = 125). Savoury pies were the most popular "lunch" item for all learners for both food breaks (45%, n = 5 schools and 27.3%, n = 3 schools) selling the most number of units (43) per day at eight of the eleven schools (72.7%). Iced popsicles were sold at almost every school, ranked as the cheapest beverage and also sold the most number of units (40.7). Healthy beverages sold included canned fruit juice and water, while healthy snacks consisted of dried fruit, fruit salad, bananas, yoghurt and health muffins. The average healthy snack contained almost half the kilojoules of its unhealthy counterpart (465kJ vs 806kJ). Nutritional analyses of the healthy lunch options revealed total fat contents that exceeded the DRI and South African recommended limit. Perceived barriers to stocking healthy items included cost and refrigeration restrictions. The average score for the food groups was only 33% indicating that learners were not familiar with the Food Based Dietary Guidelines (FBDG). Further analyses showed that the total knowledge scores of those learners that reported to buy from the tuck shop frequently, was significantly lower when compared to the total knowledge scores of those learners who bought from the tuck shop less frequently (13.0 ± 3.9 and 11.6 ± 3.1, respectively; p < 0.05). Logistic regression analysis confirmed that the total knowledge of a learner could be used to predict whether he or she is more likely to make purchases from the tuck shop (significance = 0.017). Focus group results revealed that learners are aware of “healthy” and “unhealthy” tuck shop items. Most learners stated that they would continue to purchase items from their tuck shop if all “unhealthy” items were removed. Conclusion: Primary school tuck shops of well resourced schools in Pietermaritzburg are contributing to childhood overweight and obesity through a combination of factors. These include the poor nutritional quality of the items stocked at the tuck shop as well as the poor tuck shop purchasing practices. Much consultation is required amongst dieticians, school principals and privatised tuck shop managers to overcome barriers to stocking healthy items. School management and government have an important role to play in imposing restrictions on the sale of unhealthy items; along with improving the quality of the nutrition education curriculum to ensure that learners are able to translate their knowledge into healthier purchasing practices. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2011.
362

Management of fusarium wilt diseases using non-pathogenic Fusarium oxysporum, and silicon and Trichoderma harzianum (ECO-T®)

Kidane, Eyob Gebrezgiabher. January 2008 (has links)
In the genus Fusarium are many important plant pathogens. The diversity of hosts the genus attacks, the number of pathogenic taxa and the range of habitats in which they cause disease are the greatest in plant pathology. One important species complex within the genus Fusarium is Fusarium oxysporum Schlecht. This species complex consists more than 80 pathogenic forma specialis and is particularly difficult to control. The fungi can survive in soil for decades as specialized spores, known as chlamydospores. Interestingly, however, this species complex also contains beneficial non-pathogenic forms that can be exploited to manage Fusarium wilt diseases. In this study, the ability of non-pathogenic F. oxysporum strains, Trichoderma harzianum Rifai Eco-T®, soluble silicon, and their combination was evaluated on two important crops, banana (Musa sp. L.) and beans (Phaseolus vulgaris L.), for their potential to suppress pathogenic strains of F. oxysporum. The ability of these crops to take up and accumulate silicon in their organs, and its effect on low temperature stress was also investigated. Several endophytic fungi, mainly Fusarium spp. and bacteria, were isolated from healthy mature banana plants. After preliminary and secondary in vivo screening tests against F. oxysporum f.sp. phaseoli on beans (Phaseolus vulgaris L.) cv. Outeniqua, two non-pathogenic F. oxysporum strains were selected for further testing. These two non-pathogenic F. oxysporum strains were found to colonize banana (Musa sp.) cv. Cavendish Williams and bean plants, and to suppress Fusarium wilt of these crops. In order to improve the efficacy of these biocontrol fungi, soluble silicon was introduced. The relationship between plant mineral nutrition and plant diseases have been reported by several authors. Plants take up silicon equivalent to some macronutrients, although it is not widely recognized as an essential element. In this study, we established that roots, the target plant organ for soilborne plant pathogens, accumulated the greatest quantity of silicon of any plant organs when fertilized with high concentrations of silicon. On the other hand, the corm and stem accumulated the least silicon. Such observations contradict the concept of passive uptake of silicon via the transpiration stream in these plants as the only uptake mechanism. The prophylactic properties of silicon have been documented for many crops against a variety of diseases. In vitro bioassay tests of silicon against these wilt pathogens showed that silicon can be toxic to Fusarium wilt fungi at high concentrations (>7840 mg .-1), resulting in complete inhibition of hyphal growth, spore germination and sporulation. However, low concentrations of silicon (<490 mg .-1) encouraged hyphal growth. Silicon fertilization of banana and beans significantly reduced disease severity of these crops by reducing the impact of the Fusarium wilt pathogens on these crops. However, it could not prevent infection of plants from the wilt pathogens on its own. Synergistic responses were obtained from combined applications of silicon and non-pathogenic F. oxysporum strains against Fusarium wilt of banana. Combinations of silicon with the non-pathogenic F. oxysporum strains significantly suppressed disease severity of Fusarium wilt of banana, caused by F. oxysporum f.sp. cubense (E.F. Smith) Snyder & Hansen, better than applications of either control measure on their own. Banana production in the subtropical regions frequently suffer from chilling injury, and from extreme variations between night and day temperatures. Such stress predisposes banana plants to Fusarium wilt disease. Silicon, on the other hand, is emerging as important mineral in the physiology of many plants, ameliorating a variety of biotic and abiotic stress factors. We established that silicon fertilization of banana plants significantly reduced chilling injury of banana plants. Membrane permeability, lipid peroxidation (MDA level) and proline levels were higher in silicon-untreated plants than the treated ones, all of which demonstrated the stress alleviating effect of silicon. Low temperatures damage the cell membrane of susceptible plants and cause desiccation or dehydration of these cells. Levels of sucrose and raffinose, recognized as cryoprotectants, were significantly higher in silicon-amended banana plants than unamended plants. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2008.
363

Studies on the use of biocontrol agents and soluble silicon against powdery mildew of zucchini and zinnia.

Tesfagiorgis, Habtom Butsuamlak. January 2008 (has links)
Powdery mildew (PM) is an important foliar disease of many crops, occurring under both greenhouse and field conditions. The application of biological control and soluble silicon (Si) against PM has received increasing acceptance as a result of increased environmental and public concern over the use of fungicides for disease management, and because many key fungicides are no longer effective because of resistance problems. However, success with these control options depends on the development of effective antagonists and understanding how best to use Si in agriculture. Potential antagonists of PM were isolated from naturally infected leaves of different plants. A total of 2000 isolates were tested in a preliminary screening on detached leaves of zucchini. The best 30 isolates showing consistent results were further tested under greenhouse conditions for their efficacy against PM of zucchini. In a greenhouse trial, 23 isolates provided disease control to levels of 30 to 77%. Application of 29 isolates resulted in significant reductions in values of area under disease progress curve (AUDPC). The best five isolates were identified as Clonostachys rosea (Link) Schroers, Samuels, Seifert & Gams (syn. Gliocladium roseum) (Isolate EH), Trichothecium roseum (Pers.) Link (syn. Cephalothecium roseum) (Isolate H20) and Serratia marcescens (Bizio) (Isolates B15, Y15 and Y41). Three adjuvants (Break-ThruR (BK), PartnerR (PR) and Tween-80R (T-80)) were compared for their ability to improve efficacy of spray application of silicon (Si) and biocontrol agents (BCAs) against PM. Both BK and PR improved the efficacy of Si significantly (P < 0.05). Microscopic studies showed that BK affected PM fungi directly and enhanced the deposition of BCAs on the pathogen. Break-ThruR was only toxic to the pathogen mycelia when used at > 0.25 m. .-1, but phytotoxic to zucchini plants when used at > 0.45m. .-1. However, it did not affect the c.f.u. of bacterial BCAs. Use of BK at 0.2-0.4 m. .-1 can be recommended to assist spray application of Si (at 750 mg .-1) or BCAs for improved control of PM. The effect of concentration, frequency of application and runoff of Si sprays applied to the foliage was evaluated for control of PM of zucchini. Silicon (250-1000 mg .-1) + BK (0.25 m. .-1), was sprayed onto zucchini plants at frequencies of 1-3 wk-1. Spraying Si reduced the severity of PM significantly (P < 0.05). Regardless of the concentration of Si, the best results were obtained when the frequency of the treatment was increased, and when spray drift or spray runoff were allowed to reach the rhizosphere of the plants. When Si was applied onto leaves, direct contact between the spray and the pathogen resulted in mycelial death. Part of the spray (i.e., drift and runoff) was absorbed by plant roots, and subsequently played an important role in the health of the plants. If affordable, soluble Si should be included in nutrient solutions of hydroponics or supplied with overhead irrigation schemes when PM susceptible crops are grown. Under greenhouse conditions, application of BCAs, with or without Si, reduced the severity and development of PM significantly (P < 0.001). Application of Si significantly reduced the severity and AUDPC values of PM (P < 0.05 for both parameters). Silicon alone reduced the final disease level and AUDPC values of PM by 23-32%, and improved the efficacy of most BCAs. In the course of the investigation, antagonistic fungi consistently provided superior performances to bacterial isolates, providing disease control levels of up to 90%. Higher overall disease levels reduced the efficacy of Si against PM, but did not affect the efficacy of BCAs. Under field conditions, Si alone reduced disease by 32-70%, Isolate B15 reduced disease by 30-53% and Isolate B15 + Si reduced disease by 33-65%. Other BCAs applied alone or together with Si reduced the disease level by 9-68%. Most BCAs reduced AUDPC values of PM significantly. For most antagonists, better efficacy was obtained when Si was drenched into the rhizosphere of the plant. However, efficacy of some of the BCAs and Si were affected by environmental conditions in the field. Repeated trials and better understanding of how to use Si and the BCAs, in terms of their concentration and application frequency, and their interactions with the plant and the environment, are needed before they can be used for the commercial control of PM. Elemental analysis was conducted to determine the impact of differing application levels of silicon (Si) in a form of potassium silicate (KSi) in solution in terms of Si accumulation and selected elements in different tissues of zucchini and zinnia and growth of these plants, and to study the effect of PM on the levels of selected elements in these two plant species. Plants were grown in re-circulating nutrient solutions supplied with Si at different concentrations and elemental composition in different parts were analysed using EDX and ICP-OES. Increased levels of Si in the solution increased the levels of Si in leaves and roots of both plants without affecting its distribution to other plant parts. In zucchini, the roots accumulated the highest levels of Si, substantially more than in the shoots. In contrast with zinnia, accumulation of Si was highest in the leaves. Accumulation of potassium (K) in shoots of both plants increased with increased levels of KSi in the nutrient solution. However, K levels in flower of zinnia, fruits of zucchini and roots of both plants remained unaffected. Increased level of Si reduced accumulation of calcium (Ca) in both plants. Adding Si into the nutrient solution at 50 mg .-1 resulted in increased growth of zucchini and increased uptake of P, Ca, and Mg by both plant species. However, application of higher levels of Si did not result in any further biomass increase in zucchini. Levels of Si in the nutrient solution had no effects on elemental composition and characteristics of the fruits of zucchini. In both plant species, the presence of PM on the leaves of plants resulted in these leaves accumulating higher levels of Si and Ca, but less P, than leaves of uninfected plants exposed to the same levels of soluble Si. The highest concentrations of Si were observed in leaf areas infected with PM, and around the bases of trichomes. For optimum disease control and maximum accumulation of different elements in these two plants, hydroponic applications of Si at 50-150 mg .-1 is recommended. Five selected biocontrol agents and potassium silicate, used as source of soluble Si, were tested under hydroponic conditions at various concentrations against PM of zinnia (Glovinomyces cichoracearum (DC) Gelyuta, V.P.). Application of BCAs resulted in reductions in final disease level and AUDPC values of PM by 38-68% and 30-65%, respectively. Both severity and AUDPC values of PM were reduced by 87-95% when plants were supplied with Si (50-200 mg .-1). It is proposed that the provision of a continuous supply of Si and the ability of this plant species to accumulate high levels of Si in its leaves were the major reasons for the good response of zinnia to Si treatments against PM. Silicon played a protective role before infection and suppressed development of PM after infection. The combination of the best selected BCAs and Si can be used as an effective control option against PM of zinnia when grown in hydroponic system. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2008.
364

Impact assessment of the integrated nutrition programme on child malnutrition in South Africa.

Musvaire, Rufaro. January 2009 (has links)
The Integrated Nutrition Programme (INP) was implemented in 1995 to target child malnutrition in South Africa. This study assessed the impact of the INP on child malnutrition by province and age group using secondary data. Data from three national nutrition surveys, conducted in 1994, 1999 and 2005, were used to describe trends in child stunting, underweight, wasting, vitamin A deficiency and iron deficiency. The relationship between the prevalence of the human immunodeficiency virus (HIV) in prenatal women and child nutritional status; challenges and constraints to implementing the INP at provincial level; and government responses to nutrition recommendations by lead experts in the 1994 and 1999 surveys were also investigated. Child nutritional status varied across provinces. In some provinces such as the Northern Cape, stunting, underweight and wasting remained consistently high. Stunting decreased in the Eastern Cape, but rates of wasting increased between 1994 and 2005. On the other hand, Gauteng and the Western Cape generally had lower rates of malnutrition compared to the other provinces. This may be due to these provinces being the most economically active in the country thus more opportunities for employment and higher purchasing power of foods rich in micronutrients. By 2005, vitamin A deficiency had doubled in most provinces despite mandatory food fortification being implemented in 2003. KwaZulu-Natal had the highest rates of vitamin A deficiency, while Limpopo had the highest rates of iron deficiency. By 2005, malnutrition had decreased in children aged seven to nine years, but had increased in those aged one to three years. There was a significant positive correlation (p<0.01) between the prevalence of HIV in prenatal women and vitamin A deficiency nationally. The prevalence of HIV in prenatal women was positively correlated (p<0.05) with rates of wasting in children aged one to three years. Limited skills, inadequate monitoring and evaluation, and limited infrastructure were common challenges and constraints to implementing the INP at provincial level. The effect of HIV on human resources and the higher demands of HIV infected patients also posed a challenge to provinces as they implemented the INP. Government responded to most recommendations made by nutrition experts. Supplementation,food fortification, growth monitoring and nutrition promotion programmes were implemented. Based on the data, it would appear that INP activities targeted at school-going children were more effective than those targeting children under-five. Although food fortification was implemented in 2003, the vitamin A content of fortified products might not have met legislative requirements. Additionally, because vitamin A is unstable to heat and light, if vitamin A fortified foods are cooked or stored this may also influence the bioavailability of vitamin A. Maternal HIV status might have attenuated child nutrition outcomes due to the negative effect of HIV on related health conditions such as child caring and feeding practices. Some of the challenges and constraints at provincial level might have negatively affected the implementation of the INP and consequently its impact. Although government responded to most recommendations made by nutrition experts, ongoing monitoring and evaluation of child nutritional status were not adequately done, which might have also negatively affected INP outcomes. In addition, factors in the macro-environment such as food inflation and access to basic sanitation, could have lessened the impact of the INP on child malnutrition. Interventions directed at malnutrition in children under-five need to be prioritised. There needs to be rigorous monitoring of micronutrient content, especially vitamin A, of fortified foods. Future studies need to include assessment of nutritional status in HIV affected and infected children to help identify specific needs and develop appropriate policies. Frequent nutrition surveillance to assess key child malnutrition indicators is required. / Thesis (M.Sc.) - University of KwaZulu-Natal, Pietermaritzburg, 2009.
365

Knowledge, attitudes and practices related to lifestyle factors among childbearing women in the West Coast/Winelands health district.

Maart, Lana Catherine January 1990 (has links)
<p>Many of the known risk factors associated with low birth weight, such as socio-economic status, ethnicity, genetic makeup, and obstetric history, are not within a women's immediate control. However, there are many things that a woman can do to improve her chances of having a normal healthy child. Lifestyle behaviours, such as cigarette smoking, nutrition and the use of alcohol, play an important role in determining the growth of the fetus. The aim of this study was to establish the knowledge, attitudes and practices related to lifestyle factors such as alcohol use, smoking and nutrition among childbearing women and health care workers on the farms in Stellenbosch and Vredendal.</p>
366

The relationship between dietary factors, meat consumption, heterocyclic amines, Benzo[a]pyrene, meat-derived mutagenic activity and colorectal cancer in Western Australia

Tabatabaei, Seyed Mehdi January 2009 (has links)
The role of meat consumption in the development of cancer, including colorectal cancer (CRC), has been subject of much investigation in recent years. The observation of geographical variation in CRC incidence and increased CRC risks in populations consuming high levels of meat prompted researchers to hypothesise a link between meat and CRC. An area of particular interest in CRC pathogenesis is the meat-derived compounds such are heterocyclic amines (HCAs), polycyclic aromatic hydrocarbons (PAHs), and meatderived mutagenic activity. Australia is among the countries with high incidence of CRC and also high levels of per capita meat consumption. Hence, clarifying the possible link between meat consumption and the risk of CRC in order that this can be translated into preventive dietary recommendations for the public is important. The objective of this thesis was to examine whether meat consumption is related to risk of CRC in an Australian population. The term meat consumption in this thesis means meaures of consumption of red and white meat that incorporate frequency and cooking method. The following hypotheses were investigated: 1. Increasing intake of meat prepared by methods that involve higher cooking temperature and time is positively associated with the risk of CRC; 2. Increasing exposure to meat-derived heterocyclic amines (HCAs) is positively associated with the risk of CRC; 3. Higher levels of exposure to polycyclic aromatic hydrocarbons (PAHs) from meat consumption is a risk factor for CRC; 4. Exposure to meat-derived mutagens increases the risk of CRC.
367

Measurement of fish consumption in population-based studies of cancer

Mina, Kym Deanne January 2007 (has links)
[Truncated abstract] The role of fish consumption and omega-3 polyunsaturated fatty acids (PUFAs) in the prevention of disease has been the subject of much investigation in recent years. A clue that these factors might be of importance was the observation that populations consuming high levels of marine omega-3 PUFAs had lower rates of morbidity and mortality from cardiovascular disease. From there, research in this area has expanded to include a range of chronic diseases and their prevention. An area of particular interest is the role of fish consumption in the prevention of various cancers. In Australia, one in three men and one in four women are expected to be diagnosed with cancer by the age of 75. Identifying preventive factors that can be translated into constructive health promotional messages is of great importance in addressing this group of diseases that has such a large impact on the health and wellbeing of the population. ... Results and conclusions Analysis of the data from the population-based case-control study suggests a protective effect of preserved fish consumption, possibly due to the high oil content of these fish. The developed questionnaire is a valid and reliable tool for measuring fish and seafood consumption as determined by regression analysis with an independent biomarker and reliability analysis using intra-class correlation. Importantly, reliability can be maintained despite asking a high level of detail from participants. For ranking according to overall fish consumption, detailed questioning is probably not necessary, however inclusion of variables representing multiple categories of fish and seafood consumption in a regression model enables us to better account for variation in blood omega-3 PUFA levels than a single variable representing overall consumption. For the purpose of questionnaire validation, plasma phospholipid and erythrocyte membrane levels of EPA and DHA are equivalent biomarkers of fish and seafood consumption. The choice between them by future investigators will be based on more practical aspects such as convenience and the fasting state of subjects. The tangible product of this thesis is additional evidence to support a protective association between fish consumption and prostate and breast cancers, and a valid and reliable questionnaire v for measuring habitual consumption of fish and seafood in a West Australian population, that could also be applied to other populations after minor adjustment for local fish and seafood consumption patterns.
368

Estado nutricional e fatores de risco em mulheres adultas : um estudo comparativo com descendentes quilombolas e a população do estado de Alagoas, Brasil / Nutritional status and risk factors in adult women : a comparative study with quilombolas descendants and people of the state of Alagoas, Brazil

Silva, Wcleuton Oliveira 31 March 2010 (has links)
A obesidade vem crescendo gradativamente em locais anteriormente pouco prevalentes, inclusive naqueles de baixa renda. O presente estudo foi realizado em comunidades quilombolas com o objetivo de comparar a prevalência dos fatores de riscos para doenças cardiovasculares entre mulheres dessas comunidades e de dados retrospectivos de um grupo de mulheres adultas participantes do diagnóstico Materno-infantil do Estado de Alagoas, tido como grupo de referência. Participaram desse estudo, 1665 mulheres quilombolas de 41 comunidades cadastradas na Secretaria do Estado da Mulher, da Cidadania e dos Direitos Humanos e 1158 mulheres do grupo de referência. Analisou-se a massa corporal, a estatura, o índice de massa corporal (IMC), a circunferência da cintura (CC), a relação da cintura pelo quadril (RCQ) e o percentual de gordura como indicadores de risco a desenvolver doenças cardiovasculares. Para o tratamento dos dados, foi utilizada a estatística descritiva, medidas de prevalências, razão de prevalências (RP) ajustadas pelos quartis da idade e teste de diferença entre os grupos (p<0,05). Verificou-se uma maior prevalência de risco para os pontos de corte da CC e RCQ (CC 80 cm e RCQ 0,85) nas mulheres quilombolas do que nas mulheres de referência (CC:56,27% vs 34,45%; RCQ:51,3% vs 24,32%, respectivamente). Apesar das mulheres quilombolas apresentarem maior prevalência de sobrepeso (32,4% vs 30,29%) e obesidade (18,3% vs 13,77%) quando classificadas pelos valores de IMC, apenas o 4º quartil (sobrepeso) e 3º quartil (obesidade) apresentou razão de risco significativo quando ajustado pela idade (RP: 1,2; IC 95%: 1,04 a 1,39 para o 4º quartil; RP:1,43; IC95%: 1,01 a 2,0 para o 3º quartil). Não foram encontradas diferenças significativas entre os grupos para o percentual de gordura (p=0,98), e foi demonstrado fator de proteção para RP (0,29; 0,45; 0,67 e 0,96) com o ajustamento pela idade entre os grupos, respectivamente, no 1º, 2º, 3º e 4º quartil para este indicador. Observou-se também que a idade demonstrou ser um fator de risco associado com o aumento da idade quando comparada a RP entre o 4º e 1º quartis das mulheres quilombolas. Os resultados indicam que existem importantes evidências de que a população quilombola convive com uma considerável prevalência de indicadores de doenças cardiovasculares. Portanto, as prevalências encontradas apontam para a necessidade de iniciativas emergenciais para esse grupo, no sentido de reduzir as prevalências de sobrepeso/obesidade e, consequentemente, dos fatores de risco para desenvolvimento de doenças cardiovasculares.
369

Evaluation of Iron (Fe) and Zinc (Zn) concentration among selected potato (Solanum tuberosum) genotypes in South Africa

Managa, Lavheselani Rodney 10 1900 (has links)
Potato is an important source of energy to most micronutrient malnourished affected population in South Africa. Improvements through bio-fortification can therefore enhance access to essential micronutrients. The study was aimed at determining the level of variability of iron and zinc concentration among 20 potato genotypes as a preliminary step for future breeding program. The materials were evaluated using inductively coupled plasma optical emission spectrometry. Statistical analysis indicated significant (P<0.001) variation of Fe and Zn among the genotypes. The average concentration ranges from 34.67 to 76.67 mg kg-1 and 12.88 to 66.1 mg kg-1 for iron and zinc respectively. The best performing genotypes were cultivar Mnandi, Hertha, Buffelspoort and breeding lines-N105-1, 00-S100-33 and 03-627-50. Iron concentration was positively correlated with Zinc concentration. The study showed that enough variability of Fe and Zn concentration exist among the evaluated genotypes, which can be exploited for use in potato bio-fortification breeding programme. / Agriculture, Animal Health and Human Ecology / M.Sc. (Agriculture)
370

Análise da concordância entre o plano dietético Dietary Approaches to Stop Hypertension (DASH) e o padrão alimentar de pacientes hipertensos / Analysis of the concordance between the dietary approaches to stop hypertension (DASH) and the alimentary habit of hypertensive patients

Marcela de Abreu Casanova 05 February 2010 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A adoção do plano dietético Dietary Approaches to Stop Hypertension (DASH) tem sido enfatizado na população hipertensa como uma importante estratégia no controle dos níveis pressóricos elevados. O objetivo deste estudo foi analisar o consumo alimentar de macro e micronutrientes em pacientes hipertensos, em especial do sódio, cálcio, potássio e magnésio, e comparar com as recomendações dietéticas contidas no plano DASH. Estudo transversal envolvendo uma amostra de conveniência composta por 113 hipertensos entre 40 e 69 anos. A medida da pressão arterial (PA) foi determinada com aparelho eletrônico devidamente calibrado e a avaliação dietética obtida pelo questionário de freqüência do consumo alimentar. Os alimentos ingeridos foram convertidos em porções e distribuídos em diferentes grupos alimentares. A faixa de porções recomendadas pelo plano DASH foi determinada com base na média das necessidades energéticas desta amostra permitindo assim uma posterior comparação com o hábito alimentar dos hipertensos, utilizando um escore de pontos com pontuação máxima de 9 pontos. A amostra foi dividida em três grupos: grupo B que obteve 2,5 a 4,0 pontos (n=34; 30%), grupo M entre 4,5 a 5,0 pontos (n=43; 38%) e grupo A que obteve 5,5 a 8,0 pontos (n=36; 32%). Não foram observadas diferenças significativas na média da PA sistólica (14024 vs 13823 vs 13515 mmHg) e diastólica (8617 vs 8813 vs 8410 mmHg). Apesar do grupo A consumir mais proteínas e gordura monoinsaturada, foi detectado um excesso pronunciado na ingestão de gordura saturada, colesterol e das calorias totais, por este grupo de pacientes. No que tange a ingestão dos micronutrientes, o grupo A apresentou consumo significativamente maior de cálcio, potássio e magnésio, refletido pela maior ingestão de vegetais e frutas em comparação aos grupos B e M. A média de ingestão do sódio intrínseco foi significativamente maior no grupo A (4,12,0 vs 3,11,1 vs 2,71,1 g/dia). Foram detectadas, apenas no grupo A, correlações entre PA sistólica e o percentual de proteína (r = -0,5; p=0,002) e PA sistólica e o percentual de carboidrato (r = 0,4; p=0,02). Apenas um terço dos hipertensos avaliados apresentaram padrão alimentar mais concordante com o plano DASH e com maior ingestão de proteínas, gordura monoinsaturada, fibras, cálcio, potássio e magnésio. Entretanto, o consumo mais elevado de sódio, gordura saturada, colesterol e das calorias totais por este grupo de pacientes poderia restringir uma maior queda dos níveis pressóricos elevados. / The adoption of the Dietary Approaches to Stop Hypertension (DASH) plan has been emphasized in the hypertension population as an important strategy in the control of the raised blood pressure (BP). The objective of this study was to analyze the alimentary consumption of macro and micronutrients in hypertensive patients, especially of sodium, calcium, potassium and magnesium, and to compare with the dietary recommendations contained in DASH plan. Transversal study was conducted in a convenience sample of 113 hypertensive patients, between 40 and 69 years. The BP measurement was determined with calibrated electronic device and the dietary assessment was performed trough the semiquantitative food frequency questionnaire. For comparison with DASH plan, ingested foods were converted into portions and the magnitude of the portions recommended for DASH plan was determined on the basis of the mean energy requirements of this sample. Thereafter, cut-off points were established for food groups, the maximum number of points that a patient could reach was 9. The sample was divided in tertils: Group L with 2.5 4.0 points (n=34; 30%), Group I with 4.5 5.0 points (n=43; 38%) and Group H with 5.5 8.0 points (n=36; 32%). Systolic and diastolic BP were not significantly different among the groups (14024 vs 13823 vs 13515 mmHg/ 8617 vs 8813 vs 8410 mmHg). Group H consumed more proteins and monoinsaturated fat, a pronounced excess in the saturated fat, cholesterol and total calories intake was also detected in this group of patients. Regarding micronutrients intake, group H presented significantly higher consumption of calcium, potassium and magnesium, reflected for higher vegetable and fruits intake in comparison to the groups L and I. The average of intrinsic sodium intake was significantly higher in the group H (4.12.0 vs 3.11.1 vs 2.71.1 g/day). Negative correlation between the systolic BP and dietary protein percentage (r=-0.5, p=0.002) and a positive correlation between the systolic BP and the carbohydrate percentage (r=0.4, p=0.02) was verified only in group H. The present study showed that only one third of the hypertensive patients presented alimentary pattern more consistent with DASH plan, showing greater intake of protein, monounsaturated fat, fiber, calcium, potassium and magnesium. However, pronounced sodium, saturated fat and cholesterol intake and excess of total calories in these hypertensive patients could restrict a greater control of BP.

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