Thesis (M. Tech. (Biomedical Technology)) -- Central University of Technology, Free State, [2014] / Pica is the habitual eating of non-food substances by humans and animals. It has different subgroups and these are defined by the ingested substance. Moreover, geophagia is a type of pica that refers to the consistent eating of mostly earth and earth-like substances such as clay and soil. It is observed in both sexes, all age groups and in different ethnic groups around the world. There are many reasons people give for the practice of geophagia, such as culture, hunger and health being the most prominent. Geophagic materials differ in texture, colour and taste. Soil colour classification according to the Munsell soil classification, which uses hues, values and chroma, sometimes differ with the soil colour being noticeable with the naked eye. However, geophagic clays from Qwa-Qwa are white and contain kaoline. Geophagic materials are believed to augment mineral deficiency, especially magnesium, calcium and iron. Geophagia is practised mainly by females, especially during their child bearing years. Females are more prone to iron deficiency anaemia due to their monthly menstruation cycle. Iron deficiency is the most common cause of anaemia and is classified as hypochromic microcytic anaemia (HMA). This study focused on the health aspect of geophagia. The research question seeks to explore whether there is an association between geophagia and the haematological parameters of iron deficiency anaemia. Geophagia seems to be linked with the occurrence of anaemia, but not iron deficiency anaemia, although it is implied. It is not known if the practice of geophagia causes iron deficiency anaemia or if it is because of iron deficiency anaemia that people practise geophagia. A pilot study was done in 2007, and the results of that study prompted that this study be performed on a bigger scale. The lack of information regarding the quantity, frequency and type of geophagic material consumed the impact of geophagia on haematological parameters and the iron status of the geophagists made it important that the primary existence of the iii relationship be investigated. In addition, research to establish whether there is a relationship between geophagia and haematological parameters of iron deficiency anaemia, has not been undertaken in South Africa, especially on non-pregnant women. Geophagia seems to always be accompanied by the subject of iron deficiency anaemia and especially its prevalence in females. The bigger geophagia project was therefore an ideal opportunity to do a specific survey on geophagic women. This was a cross-sectional study, consisting of 36 control women and 47 geophagic women, aged between 18-45 years. The participants completed a questionnaire to determine the geophagic practices, which included the colour of the clay, how frequent the clay was consumed, how much was consumed and for how long it has been consumed. Nutritional status was assessed using a food frequency questionnaire. Blood was drawn to assess the haematological and iron status of the participants. The participants of the study were within the required age range, with no significant difference between the groups (p-value=0.7914). The most consumed colour of clay was white and white clay contains kaoline, which has the ability to absorb iron in the duodenum. The majority of the participants consumed 40 grams of clay on a daily basis, with most of the participants having done so for 5 years. Diet was ruled out as the cause of iron deficiency. The haematological parameters indicated that the geophagic group (43%) were inclined to have hypochromic microcytic anaemia, while a small percentage of control groups (8%) had HMA; this was revealed by the red cell parameters and red cell indices. In addition, the odds ratio for the haematological results revealed that the probability of a geophagic person developing anaemia was two times greater than that of a non-geophagic person. Platelet results partially ruled out bleeding as a cause of anaemia. The median red cell distribution width indicated that the iv geophagic group was inclined to have anisocytosis. The geophagic group was found to have iron deficiency (75%), whilst the control group had a small percentage with iron deficiency (22%), which was validated by the serum ferritin, serum iron and saturated transferrin (chemical analysis). The odds ratio revealed that the probability of a geophagic person being iron deficient is 3 times greater than that of a non-geophagic person. The strongest association is seen with iron study findings, because being iron deficient showed the highest odd ratio than the association with red cell morphology and even haemoglobin. Thus, participants were more iron deficient than suffering from iron deficiency anaemia. Inflammatory and parasitic indicators proved that inflammation and infection was uncommon in both groups, and therefore did not compromise the credibility of the iron study results. Inflammatory indicators (white blood cells, erythrocyte sedimentation rate and C-reactive protein) ruled out inflammation, whilst eosinophil count showed no indication of parasitic infection for both geophagic and control groups. To conclude, the study found that an association exists between geophagia and haematological parameters of iron deficiency anaemia amongst geophagic women in Qwa-Qwa, in that geophagic material contributes to iron deficiency anaemia.

Introdução: O estado nutricional da gestante constitui importante fator para o desenvolvimento do feto e da gravidez saudável. Mulheres que apresentam ingestão inadequada de nutrientes têm maior probabilidade de desenvolver gestação de risco. Essa problemática é especialmente intensa quando a mulher apresenta quadro de transtorno alimentar (TA). Este trabalho abordou aspectos históricos, etiologia e epidemiologia dos TA, contemplou os critérios diagnósticos, concebeu os TA no período gravídico puerperal e dissertou sobre TA, sintomatologia ansiosa e depressiva. Os objetivos deste estudo foram determinar a prevalência de TA em gestantes com intercorrências clínicas e verificar a associação com sintomatologia ansiosa, depressiva e atitudes alimentares. Método: Estudo prospectivo transversal foi realizado com 913 gestantes com intercorrências clínicas que estavam no 2° ou 3° trimestre gestacional no ambulatório da Divisão de Clínica Obstétrica do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. Foi utilizada entrevista dirigida, para avaliação de picacismo; o EAT-26, para avaliar as atitudes alimentares; Structured Clinical Interview for DSM Disorders, para diagnóstico clínico de TA e a escala Hospital Anxiety and Depression, para análise da sintomatologia ansiosa e depressiva. Os dados deste estudo foram submetidos à análise quantitativa e avaliados por meio do programa IBM SPSS for Windows versão 20.0. Resultados: constatou-se prevalência de transtorno alimentar em 7,6% (n=69) (IC 95%: 5,84%-9,28%), sendo 0,1% (n=1), anorexia nervosa; 0,7% (n=6), bulimia nervosa; 1,1% (n=10), transtorno da compulsão alimentar e 5,7% (n=52), picacismo. Encontrou-se significância estatística quando associado TA com as variáveis: religião (p=0,02), abortamento provocado anterior (p < 0,01), tempo de relacionamento (p=0,01), renda per capita (p=0,04), número de gestações (p < 0,01) e número de filhos vivos (p < 0,01). Quanto às atitudes alimentares, observou-se significância estatística com \"sentir-se mal após comer doces\" (p=0,02) e \"passar muito tempo pensando em comida\" (p < 0,01). Constatou-se ainda associação positiva com sintomatologia ansiosa (p < 0,01) e com sintomatologia depressiva (p < 0,01). Conclusão: a prevalência de TA encontrada (7,6%) e sua associação com sintomatologia ansiosa e depressiva, durante a gestação, apontam para a necessidade de cuidados especializados no que diz respeito à prevenção, diagnóstico e tratamento. Dada a importância da alimentação adequada no período gestacional, tanto no que diz respeito à saúde materna, quanto ao desenvolvimento fetal, torna-se necessário implementar, pelos profissionais de saúde, avaliação específica com protocolo predeterminado para diagnóstico de TA no período gestacional / Introduction: The nutritional status of the pregnant woman represents an important factor for the development of the fetus and for a healthy pregnancy. Women who have inadequate nutrient intake are more likely to develop a risky pregnancy. This problem is particularly severe when the woman presents an eating disorder (ED). This paper discusses the historical aspects, etiology and epidemiology of ED, considers the diagnostic criteria, delineates ED in the puerperal pregnancy period and addresses ED, anxiety and depression symptoms. The aims of this study were to estimate the prevalence of ED in pregnant women with clinical complications and to assess the relationship between anxiety and depression symptoms and eating attitudes. Methods: A transversal and prospective study was conducted with 913 women between 2nd and 3rd trimester with high-risk pregnancies in the Obstetrics Clinic Division of Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. We conducted structured interviews for the assessment of pica, Structured Clinical Interview for DSM Disorders for diagnostic of ED and Hospital Anxiety and Depression Scale for anxiety and depression symptoms, and applied the EAT-26 questionnaire for eating attitudes. The data analysis was quantitative and conducted with the IBM SPSS for Windows, version 20.0. Results: Lifetime prevalence of ED was 7.6% (n=69) (95% CI: 5.84%-9.28%), 0.1% (n=1) for anorexia nervosa; 0.7% (n=6) for bulimia nervosa; 1.1% (n=10) for binge eating disorder, and 5.7% (n=52) for pica. ED was statistically significant with respect to the following variables: religion (p=0.02), previous induced abortion (p < 0.01), being in a relationship (p=0.01), per capita income (p=0,04), number of previous pregnancies (p<0.01) and number of children (p < 0.01). For the eating attitudes, statistical significance was found with \"feeling ill after eating sweets\" (p < 0.02) and \"spend too much time thinking about food\" (p=0.05), as well as between ED and anxiety (p < 0.01) and depressive symptoms (p < 0.01). Conclusion: The prevalence of ED (7.6%) and its association with anxiety and depression symptoms during pregnancy highlights the need for specialist care for prevention, diagnosis and treatment. Given the importance of proper nutrition during pregnancy, both with regard to maternal health and fetal development, it is necessary to have specific predetermined evaluation protocols implemented by health care professionals for the diagnosis of ED during pregnancy

Introdução: O estado nutricional da gestante constitui importante fator para o desenvolvimento do feto e da gravidez saudável. Mulheres que apresentam ingestão inadequada de nutrientes têm maior probabilidade de desenvolver gestação de risco. Essa problemática é especialmente intensa quando a mulher apresenta quadro de transtorno alimentar (TA). Este trabalho abordou aspectos históricos, etiologia e epidemiologia dos TA, contemplou os critérios diagnósticos, concebeu os TA no período gravídico puerperal e dissertou sobre TA, sintomatologia ansiosa e depressiva. Os objetivos deste estudo foram determinar a prevalência de TA em gestantes com intercorrências clínicas e verificar a associação com sintomatologia ansiosa, depressiva e atitudes alimentares. Método: Estudo prospectivo transversal foi realizado com 913 gestantes com intercorrências clínicas que estavam no 2° ou 3° trimestre gestacional no ambulatório da Divisão de Clínica Obstétrica do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. Foi utilizada entrevista dirigida, para avaliação de picacismo; o EAT-26, para avaliar as atitudes alimentares; Structured Clinical Interview for DSM Disorders, para diagnóstico clínico de TA e a escala Hospital Anxiety and Depression, para análise da sintomatologia ansiosa e depressiva. Os dados deste estudo foram submetidos à análise quantitativa e avaliados por meio do programa IBM SPSS for Windows versão 20.0. Resultados: constatou-se prevalência de transtorno alimentar em 7,6% (n=69) (IC 95%: 5,84%-9,28%), sendo 0,1% (n=1), anorexia nervosa; 0,7% (n=6), bulimia nervosa; 1,1% (n=10), transtorno da compulsão alimentar e 5,7% (n=52), picacismo. Encontrou-se significância estatística quando associado TA com as variáveis: religião (p=0,02), abortamento provocado anterior (p < 0,01), tempo de relacionamento (p=0,01), renda per capita (p=0,04), número de gestações (p < 0,01) e número de filhos vivos (p < 0,01). Quanto às atitudes alimentares, observou-se significância estatística com \"sentir-se mal após comer doces\" (p=0,02) e \"passar muito tempo pensando em comida\" (p < 0,01). Constatou-se ainda associação positiva com sintomatologia ansiosa (p < 0,01) e com sintomatologia depressiva (p < 0,01). Conclusão: a prevalência de TA encontrada (7,6%) e sua associação com sintomatologia ansiosa e depressiva, durante a gestação, apontam para a necessidade de cuidados especializados no que diz respeito à prevenção, diagnóstico e tratamento. Dada a importância da alimentação adequada no período gestacional, tanto no que diz respeito à saúde materna, quanto ao desenvolvimento fetal, torna-se necessário implementar, pelos profissionais de saúde, avaliação específica com protocolo predeterminado para diagnóstico de TA no período gestacional / Introduction: The nutritional status of the pregnant woman represents an important factor for the development of the fetus and for a healthy pregnancy. Women who have inadequate nutrient intake are more likely to develop a risky pregnancy. This problem is particularly severe when the woman presents an eating disorder (ED). This paper discusses the historical aspects, etiology and epidemiology of ED, considers the diagnostic criteria, delineates ED in the puerperal pregnancy period and addresses ED, anxiety and depression symptoms. The aims of this study were to estimate the prevalence of ED in pregnant women with clinical complications and to assess the relationship between anxiety and depression symptoms and eating attitudes. Methods: A transversal and prospective study was conducted with 913 women between 2nd and 3rd trimester with high-risk pregnancies in the Obstetrics Clinic Division of Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. We conducted structured interviews for the assessment of pica, Structured Clinical Interview for DSM Disorders for diagnostic of ED and Hospital Anxiety and Depression Scale for anxiety and depression symptoms, and applied the EAT-26 questionnaire for eating attitudes. The data analysis was quantitative and conducted with the IBM SPSS for Windows, version 20.0. Results: Lifetime prevalence of ED was 7.6% (n=69) (95% CI: 5.84%-9.28%), 0.1% (n=1) for anorexia nervosa; 0.7% (n=6) for bulimia nervosa; 1.1% (n=10) for binge eating disorder, and 5.7% (n=52) for pica. ED was statistically significant with respect to the following variables: religion (p=0.02), previous induced abortion (p < 0.01), being in a relationship (p=0.01), per capita income (p=0,04), number of previous pregnancies (p<0.01) and number of children (p < 0.01). For the eating attitudes, statistical significance was found with \"feeling ill after eating sweets\" (p < 0.02) and \"spend too much time thinking about food\" (p=0.05), as well as between ED and anxiety (p < 0.01) and depressive symptoms (p < 0.01). Conclusion: The prevalence of ED (7.6%) and its association with anxiety and depression symptoms during pregnancy highlights the need for specialist care for prevention, diagnosis and treatment. Given the importance of proper nutrition during pregnancy, both with regard to maternal health and fetal development, it is necessary to have specific predetermined evaluation protocols implemented by health care professionals for the diagnosis of ED during pregnancy

Estudio de caso para optar al grado de magíster en Estrategia Internacional y Política Comercial. / Las Indicaciones Geográficas son activos intangibles que otorgan valor a un producto con características únicas derivadas de su lugar de origen. Estos productos son altamente cotizados en mercados internacionales, ya que actualmente, consumidores adquieren productos que certifiquen su calidad, reputación y origen. En el caso de Chile, no existe una sensibilización acerca de la importancia de estos Derechos de Propiedad Intelectual, sólo existen 12 productos registrados. El Limón de Pica fue el primer producto en obtener esta certificación en el año 2010. Este estudio da a conocer los principales motivos de un grupo de productores para obtener la Indicación Geográfica del Limón de Pica, y determinar los efectos que esta obtención trajo al desarrollo de la localidad de Pica. Se entrega información acerca del trabajo que realizaron productores, el sector público y privado para obtener el registro y, posteriormente, para posicionar al Limón de Pica en el mercado nacional e internacional. Siete años después de obtener el registro, factores cómo el desconocimiento acerca del tema, la falta de asociatividad entre productores y los proyectos a corto plazo, han impedido su utilización. El sector público les ha dado un gran apoyo para sacar adelante su Indicación Geográfica, pero parecen no responder a las verdaderas necesidades de los actores. / Geographical Indications are intangible assets that add value to a product with unique characteristics deriving from their geographical origin. These products are highly valued in international markets and, nowadays, consumers mainly acquire certified products that protect their quality, reputation and origin. In the Chilean case, there is a need to increase awareness about the importance of Intellectual Property Rights, specially about Geographical Indications. There are only 12 products registered in Chile and Limón de Pica was the first product that obtained this certification in 2010. This investigation shows the main reasons why a group of people obtained Limón de Pica Geographical Indication, and it determines its effects on the local development of Pica. This investigation also gives information regarding how farmers, and the public and private sector worked to obtain this certification and to promote Limón de Pica in both national and international markets. Seven years have passed since they received the certification, but elements such as lack of knowledge, lack of cooperative work and short-time projects, have hindered its use. The public sector has provided them with a great support to develop their Geographical Indication, but it seems that they have not been able to fulfill farmers’ true needs.

Made available in DSpace on 2014-12-17T14:55:47Z (GMT). No. of bitstreams: 1 JoseSBL_DISSERT.pdf: 1769944 bytes, checksum: 43863b3b32771c922314a0fa73be8bf8 (MD5) Previous issue date: 2011-02-14 / This work deals with an on-line control strategy based on Robust Model Predictive Control (RMPC) technique applied in a real coupled tanks system. This process consists of two coupled tanks and a pump to feed the liquid to the system. The control objective (regulator problem) is to keep the tanks levels in the considered operation point even in the presence of disturbance. The RMPC is a technique that allows explicit incorporation of the plant uncertainty in the problem formulation. The goal is to design, at each time step, a state-feedback control law that minimizes a 'worst-case' infinite horizon objective function, subject to constraint in the control. The existence of a feedback control law satisfying the input constraints is reduced to a convex optimization over linear matrix inequalities (LMIs) problem. It is shown in this work that for the plant uncertainty described by the polytope, the feasible receding horizon state feedback control design is robustly stabilizing. The software implementation of the RMPC is made using Scilab, and its communication with Coupled Tanks Systems is done through the OLE for Process Control (OPC) industrial protocol / Este trabalho tem como objetivo desenvolver uma estrat?gia de controle on-line baseado no Controlador Preditivo Robusto (RMPC, acr?nimo do ingl?s Robust Model Predictive Control) aplicado a um sistema real de tanques acoplados. Este processo consiste em sistema de dois tanques conectados, cujo liquido ? enviado aos mesmos por uma bomba. O objetivo do controle (problema regulat?rio) ? deixar os n?veis dos tanques no ponto de opera??o considerado, mesmo na presen?a de perturba??es. A s?ntese da t?cnica RMPC consiste em incorporar de forma explicita as incertezas da planta na formula??o do problema. O objetivo do projeto, a cada per?odo de amostragem, ? encontrar uma realimenta??o de estados que minimiza o pior caso de uma fun??o objetivo com horizonte infinito, sujeita a restri??es no sinal de controle. O problema original, do tipo Min-max, ? reduzido em a problema de otimiza??o convexa expresso em desigualdades matriciais lineares (LMI, Linear Matriz Inequalities). Mostram-se, neste trabalho, a descri??o da incerteza da planta na forma polit?pica e as condi??es de factibilidade do problema de otimiza??o. A implementa??o do algoritmo RMPC foi feita utilizando o software Scilab e a sua comunica??o com o sistema de tanques acoplados foi feita atrav?s do protocolo OPC (do ingl?s OLE for Process Control)

No description available.

MENVSC / Department of Ecology and Resource Management / Certain communities in Sekhukhune area are known to be practicing geophagia. Existing standard questionnaires as adopted to generate data on human geophagia included aspects on demography, socio-economics, cultural, ecological, physico-chemical aspects, indigenous knowledge and health effects of geophagic consumers. These data were gathered through distribution of questionnaires to 200 geophagic participants, of which 135 were from Ga-Nchabeleng Village and 65 from Mphanama Village. Both the Villages were based in the rural settlements in Sekhukhune area. In this study the behaviour of geophagic individuals was investigated and cytotoxicity of plant remains consumed in geophagic soils was evaluated for any toxicity. A total of 17 different geophagic sites were identified. Six geophagic sites each were from Ga-Nchabeleng Village and six from Mphanama Village. Five other sites were selected from sites where geophagia was not practiced and were recorded as the control sites. All the 17 soil samples were analysed using Munsell Soil Color charts for soil colour classification. Samples of plant remains were collected from the same geophagic sites where soil samples were collected. Due to similar plants and vegetation type from 17 different geophagic sites, a composite study was adopted. Geophagic consumers in Ga-Nchabeleng Village identified four plant species of plant remains consumed in the soil in the area and Mphanama village identified five species different from Ga-Nchabeleng plants. Samples of plant remains were grouped according to comparable features or characteristics. Sample 1 of plant remains was composed mainly of grasses; Cynodon dactylon, Aristida congesta and Eragrostis rigidior whereas sample 2 of plant remains was composed of Acacia plant; Vachellia tortilis. The two samples of plant remains were collected from Ga-Nchabeleng Village. Sample 3 of plant remains was composed of creeping, perennial weed herbs; Alternanthera pungens Kunth and Alternanthera lorentzii. Sample 4 of plant remains was composed of prominent woody plants; Combretum apiculutum, Kirkia wilmsii and Boscia albitrunca. Samples of plant remains 3 and 4 were collected from Mphanama Village study sites. Sample 5 of plant remains was the control site and composed mainly of Acacia plants; Vachellia nilotica, Acacia vii mearnsii and Vachellia tortilis and were collected from sites not used for geophagic practices. The plant remains parts mostly consumed were roots (50%) in Ga-Nchabeleng, whereas in Mphanama Village they were stems (54.5%) and the control site had leaves at 62.5%. The five samples of plant remains were recovered using physical separation method. The plant remains were washed and dried. Retch Muhle grinding machine was used to ground the samples. Methanol was used in the extraction of all the samples of plant remains. The result from the administration of the questionnaire revealed that geophagia in this area was practiced by both male and female Sepedi-speaking individuals. Ga-Nchabeleng Village had more female geophagic participants, whereas Mphanama Village had more males who have almost undergone secondary school. However, in general for the study there were more female geophagic consumers. Geophagic consumers ingest soil known locally as Mobu, Letsopa or Leraga collected mostly from the riverbanks, mountains/hills and valleys with only a few that indicated termite mounds. Geophagic consumers in the study used colour, among other things, to describe their soil of preference. The study consisted of 200 participants of whom 172 represented the geophagic group and 28 were the control group, aged between 18-65 years analysed using chi-square crosstabulation. There was no significant difference in human health effects associated with geophagia between the geophagic group and the control group. There was also no association established between soil consumption and other non-food substances between geophagic group and control group. Chi-square (χ2) analyses revealed a significant association of gender with geophagic habits (p<0.05), while there was no association of age, educational level, income source and marital status (p>0.05) with geophagic habits. Findings of the survey when two villages are combined revealed that more females (75.60%) practice geophagia compared to males (24.40%). The respondents from both study sites preferred digging technique when collecting the soil. It was established that craving was mainly the reason behind the practice in the study area. Hygiene and environmental conditions were not considered when mining viii geophagic soil as the majority of them used dirty utensils, hands for collection and non-sterile bags and tins for packaging. Some of the soils were collected close to waste dumping sites as seen whilst visiting geophagic mining sites. Majority of the consumers had little or no knowledge that the soil could be harmful or if it contained any contaminants. This sample of interviewees provided valuable information on human geophagic practices in Sekhukhune area. It became clear that this practice was entrenched in the cultural behaviour of people in the area and a need for educating them on health related aspects. The cytotoxicity of methanolic extracts of plant remains on HEK-293T cell line was evaluated using MTT (3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide) assay for cell viability. The 50% cytotoxic concentration (CC50) was defined as the compound’s concentration (500, 250, 125, 62.5, 31.25, 15.625 and 7.8125 μg/ml) required for the reduction of cell viability by 50%. Evaluation of cell viability showed the methanolic extracts of plant remains on HEK-293T cell line ranged in the order of plant remains extract=3>1>4>2>5 according to their cytotoxicity activities. Plant remains extract 3 from Mphanama Village showed high cytotoxicity with a CC50 of 13.75 μg/ml, followed by plant remains extract 1 at 16.68 μg/ml, plant remains extract 4 at 58.95 μg/ml, plant remains extract 2 at 92.75 μg/ml and the control at 251.4 μg/ml, respectively. In the study only the methanolic extract was investigated for cytotoxicity using HEK-293T cell line. Further research need to be conducted on the individual plants of each plant remains to be able to have conclusive results on the cytotoxicity profile. This will indicate which specific plant part is toxic or whether they exhibit a higher CC50 only when in combination.

MESHWR / Department of Hydrology and Water Resources / Communities in South Africa have been noted to consume earthy materials such a soil among others. Geophagy is largely practised in the rural areas as opposed to urban places, and in these places the level of sanitation is low and people usual practice open defecation. The practice of Geophagia has been associated with cultural, medicinal, psychological, religious and nutritional deficiency among others. The aim of the study was to investigate the effects of open defecation on geophagic soils and water resources in Siloam village. The study also aimed to understand the reasons why people practice geophagia in Siloam village and the health effect associated with consumption of geophagic soils. To carry out the aim of the study, a questionnaire survey was conducted among women who practice geophagia between the ages of 18 and above in Siloam village. Two hundred and eighty-three (283) women were selected using snowball sampling method to take part in the study. From the (283) women, (200) women represent the geophagic group and (83) women represent the control group. The existing standard questionnaire adopted to generate data on human geophagia included aspects on demography, socio-economic, cultural, ecological, physicochemical aspects, indigenous knowledge and health effects of geophagic consumers. Participants were asked basic questions on why they practice geophagy, their geophagic material preferences, where they collect the geophagic material and other related questions. A total of twelve soil samples were collected from Siloam village, from the twelve soil samples collected eight were collected from sites known for geophagic practice and another four soil samples were collected from sites where geophagia is not practiced and the samples were used as control soil samples. All the twelve soil samples were analysed for the presence of geohelminths ova using Ammonium Bicarbonate Protocol (AMBIC protocol). The AMBIC protocol consists of four analytical procedures, namely, sample preparation, sample washing with AMBIC solution, geohelminths ova recovery through a modified zinc flotation method and microscopic analysis. vi Furthermore, a total of twelve water samples were collected from Nzhelele River and ponds water in Siloam village. From the twelve water samples, eight samples were collected close to where geophagic materials were collected and where open defecation is reported to be taking place and the remaining four water samples were collected randomly from Nzhelele river and water ponds in Siloam village and was recorded as a control group. A total of 12 water samples were analysed for total coliform and faecal coliform Escherichia Coli (E.coli) indicator using the membrane filter technique. The results from the administration of the questionnaire revealed there was prevalence in the practice of geophagia in the area. The study found that most of the villagers in Siloam consumed soil nearly on daily basis. According to the results, only women were involved in the geophagic practices in the area. Additionally, the study revealed that geophagic consumers were mainly in the age of child bearing age group and reddish and yellowish soils were the most preferred. Furthermore, the results showed that geophagic consumers in the area generally consumed soil commonly because of cravings and pregnancy, however, those who were not pregnant also consumed soil. The respondents reported that they mostly consumed clay and this material was consumed in its dry state and mostly unprocessed, if processed, it would be baked. This geophagic material was mainly found in the wild (riverbed, valley etc.); it was also found that most of the soil consumers did not know that the substances they consumed could be harmful to them. Among those who knew the consequences of consuming the material stated that soil consumption causes constipation, tooth decay, body poisoning, and abdominal pains. The results from the control group, 83 women who do not practice geophagia, aged between 18 and above, analysed using chi-square revealed a significant association of age with consuming soils (p<0.05), while there was no association of income source (p>0.05) and educational level (p>0.05) with consuming soils. Chi-square (χ2) analyses further revealed that there was no association of knowledge on the harmful nature of the substance (p>0.05), frequency of getting infections (p>0.05) and experiencing chronic illnesses (p>0.05) with frequency of consuming soils. vii The results of geophagic soils revealed the absence of geohelminths ova in the entire geophagic sample. Meaning geophagic consumers in Siloam village are not at risk of acquiring geohelminths infection which may be of potential risk to human health. However, geophagic consumers may be exposed to various other potentially hazardous biological and non-biological soil contents. The results of the water samples revealed that most of the water samples in the areas where open defection is reported to be practised had higher composition of faecal and total coliform bacteria. The composition was above the South African recommended standard for negligible risk of microbial infection. This has caused a great threat to those who consume soil collected near water resources, especially from riverbed and those who also use these water sources on their daily basis. The study recommends that geophagic consumers should continue to bake their materials before consumption as it might reduce the bacteria and toxic substances found in soils. The study also recommends that the residents of Siloam be made aware of the potential health hazards that might be posed to soil consumers and the effects of practicing open defecation near community water resources as high level of faecal coliform (E. coli) were found in the water. / NRF

MESMEG / Department of Mining and Environmental Geology / Literature indicated that several mineralogical identification studies have been carried out on clays but few have focused on the characterisation of geophagic materials from South Africa. Large quantities of earth materials are consumed daily in Mashau Village, however, their mineral content and geochemical compositions had not been determined. Moreover, though the consumption of geophagic materials is very common in the village, the associated health implications had not been addressed. Thus, the main aim of the research was to mineralogically and geochemically characterise geophagic materials commonly ingested in Mashau Village and infer on possible health implications that could result from their consumption. Questionnaires were administered to geophagists in the study area with the aim of generating data on the prevalence of geophagia and the motivations for the practice. Geophagic soils and their parent rocks (for determination of provenance) were sampled and analysed for mineralogical and geochemical content. Geophagic soil samples were subjected to the following physicochemical analyses: colour, particle size distribution, pH, cation exchange capacity (CEC) and electrical conductivity (EC). An x-ray diffractometer (XRD) was used for mineralogical analysis while major oxides and trace elements abundances were determined using x-ray fluorescence (XRF) spectrometry and laser ablation inductively coupled mass spectrometry (LA-ICP-MS), respectively. Furthermore, provenance of the geophagic materials was determined using data obtained from mineralogical and geochemical analysis. Inferred health implications were based on the physico-chemical, mineralogical and geochemical data obtained. Outcomes of the questionnaire survey revealed craving to be the motivation for geophagia in Mashau Village. Although the practice seemed to be prevalent in females of certain ages, it was certainly not limited to gender, age, educational level or socio-economic status. Out of the 20 geophagic samples, 3 samples were brown, 2 had a strong brown colour and another 2 had a light olive brown colour. Other soil colours were less common, as each colour was only observed in one sample. The sand fraction dominated the samples; the clay content was low, giving the samples a sandy clay loamy texture. The pH of the soil ranged from being slightly acidic (5.4) to being slightly alkaline. The CEC values were very high ranging from 17 t0 109 meq/100 g. vii The EC values were also high (ranging from 11.2 to 245 μS/cm) indicating a high amount of soluble salts. Mineralogical analysis of geophagic soils identified quartz, microcline, plagioclase, hornblende, dolomite, muscovite, kaolinite, smectite, talc, anatase, hematite, ilmenite, chlorite and epidote with quartz and kaolinite being the dominant minerals. Actinolite, augite, chlorite, epidote, forsterite, magnetite, muscovite, plagioclase, quartz, sepiolite and microcline were the minerals identified in rock samples. Geochemical analysis for major oxides content (SiO2, TiO2, Al2O3, Fe2O3, MnO, MgO, CaO, Na2O, K2O, P2O5 and Cr2O3) indicated that both geophagic soils and parent rocks were mainly composed of silica and alumina. Trace elements geochemistry showed a depletion of LREEs and an enrichment of HREEs in geophagic soils. The results also revealed that the REEs were enriched in the bulk fraction than in the clay fraction. Relative to the Upper Continental Crust (UCC) compositions, the concentrations of trace elements in geophagic soils were generally low. Provenance determination results showed that geophagic soils in Mashau were derived from basalts and sandstones. Majority of the samples were formed as a result of intense weathering while some were as a result of intermediate weathering. The negative health implications of the studied materials could include perforation of the colon, damage of the dental enamel and anaemia. However, geophagic materials could also be a good source of mineral nutrients and beneficial for reduction of nausea during pregnancy. / NRF

This thesis presents various integrated antenna solutions for different types of systems and applications, e.g. wireless sensors, broadband handsets, advanced base stations, MEMS-based reconfigurable front-ends, automotive anti-collision radars, and large area electronics. For wireless sensor applications, a T-matched dipole is proposed and integrated in an electrically small body-worn sensor node. Measurement techniques are developed to characterize the port impedance and radiation properties. Possibilities and limitations of the planar inverted cone antenna (PICA) for small handsets are studied experimentally. Printed slot-type and folded PICAs are demonstrated for UWB handheld terminals. Both monolithic and hybrid integration are applied for electrically steerable array antennas. Compact phase shifters within a traveling wave array antenna architecture, on single layer substrate, is investigated for the first time. Radio frequency MEMS switches are utilized to improve the performance of reconfigurable antennas at higher frequencies. Using monolithic integration, a 20 GHz switched beam antenna based on MEMS switches is implemented and evaluated. Compared to similar work published previously, complete experimental results are here for the first time reported. Moreover, a hybrid approach is used for a 24 GHz switched beam traveling wave array antenna. A MEMS router is fabricated on silicon substrate for switching two array antennas on a LTCC chip. A concept of nano-wire based substrate integrated waveguides (SIW) is proposed for millimeter-wave applications. Antenna prototypes based on this concept are successfully demonstrated for automotive radar applications. W-band body-worn nonlinear harmonic radar reflectors are proposed as a means to improve automotive radar functionality. Passive, semi-passive and active nonlinear reflectors consisting of array antennas and nonlinear circuitry on flex foils are investigated. A new stretchable RF electronics concept for large area electronics is demonstrated. It incorporates liquid metal into microstructured elastic channels. The prototypes exhibit high stretchability, foldability, and twistability, with maintained electrical properties. / wisenet