Evaluation of antidiarrhoeal and toxicological properties of Hermannia Incana cav.: a South African medicinal plant
- Authors: Appidi, Jaipal Reddy
- Date: 2010
- Subjects: Sterculiaceae , Medicinal plants -- South Africa -- Eastern Cape , Diarrhea , Botany, Medical
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:11304 , http://hdl.handle.net/10353/259 , Sterculiaceae , Medicinal plants -- South Africa -- Eastern Cape , Diarrhea , Botany, Medical
- Description: Hermannia incana Cav. (Sterculiaceae), known as sweet yellow bells, is a medicinal plant used by the people of the Eastern Cape for the treatment of stomach-ache and diarrhoea. It has purgative and diaphoretic effects. It is a prostrate herb with yellow flowers and sparsely hairy and slightly glandular leaves, occurring in grassland and marshes in the Eastern Cape Province of South Africa. Based on the ethnomedical uses of this plant, the research project was designed to evaluate its antidiarrhoeal and toxicological properties. An ethnobotanical study of plants used for the treatment of diarrhoea in the Eastern Cape Province was carried out, using a questionnaire which was administered to herbalists, traditional healers and rural dwellers. This survey indicated a total of 17 plant species from 14 families. Elephantorrhiza elephantine (Burch.) Skeels, Hermannia incana Cav., Pelargonium reniforme Curt., Alepidea amatymbica Eckl. & Zeyh. and Bulbine latifolia (L.f.) Roem. et Schult. were the most frequently mentioned and highly recommended plants for the treatment of diarrhoea by both the traditional healers and rural dwellers. The root, bark and leaves are the common parts of plants used, while decoctions and infusions are the main methods of preparation. The agar dilution method was used to study the antimicrobial activity. The methanol extracts of the plant showed appreciable activity against Gram-positive and Gram-negative bacteria at concentrations ranging from 0.5 to 7.0 mg/ml. The acetone and water extracts of both the leaves and the roots showed moderate activity against Gram positive bacteria and less activity against Gram negative bacteria. All the extracts inhibited the growth of the fungi Aspergillus flavus, Aspergillus niger, and Mucor hiemalis with growth inhibition ranging from 54.31 percent to 96.67 percent at 0.1-10 mg/ml. None of the extracts suppressed the growth of Candida albicans at the maximum concentration (10 mg/ml) tested. iii In the in vivo antidiarrhoeal evaluation using Wistar rats, the aqueous extract at all the doses tested, significantly prolonged the time of induction of diarrhoea and also reduced the frequency of diarrhoeal episodes and fecal parameters (total number, number of wet, fresh and dry weight and water content of the faeces). The percentage inhibition of defecation and intestinal content (enteropooling) were increased in dose dependent manner. The doses also reduced the intestinal transit time of charcoal, masses and volumes of intestinal fluid (gastrointestinal motility). These results are indications of antidiarrhoeal property of H. incana leaf extract with the 600 mg/kg body weight of the extract being the most effective. In the toxicological evaluation using Wistar rats, the oral administration of the extract did not produce any significant effect on the liver and kidney body weight ratios, RBC, HB, PCV, MCV MCH, MCHC, RCDW, WBC, neutrophils, monocytes and basophils cholesterol, triacylglycerol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol and atherogenic index. The extract also did not affect the levels of sodium, potassium, chloride, inorganic phosphorus, urea, creatinine, total protein, globulin, albumin, total and conjugated bilirubin. The activities of alkaline phosphatase, gamma glutamyl transferase and alanine aminotransaminase in the serum were increased by the extract whereas aspartate aminotransaminase was decreased. The levels of LUC, platelets, lymphocytes and eosinophils were significantly affected at 600 mg/kg body weight. The available evidence in this study suggests that the extract of H. incana leaf is mild, parameter and dose specific. The structure and distribution of foliar appendages on the leaves of this plant were investigated with the JEOL (JSM-6390LV) scanning electron microscope (SEM). Both glandular and non-glandular trichomes were observed. Long stalked glandular trichomes were present on both the abaxial and adaxial surfaces while short stalked glandular trichomes were present only on the adaxial surface. Glandular trichomes were capitate while nonglandular trichomes were stellate with many arms. Energy dispersive X-ray spectroscopyiv SEM showed that Al, Ca, K, Na, Ti and Si were the major constituents of the crystals analyzed from the leaf surfaces. The phytochemical screening of H. incana revealed the presence of bioactive antidiarrhoeal agents such as alkaloids, tannins, saponins, phenolics, triterpenes, cardiac glycosides, flavonoids, cardenolides and dienolides. Two flavonoids, epicatechin and 3, 5, 7, 2’ tetra-hydroxy flavone-3- O--D-glucopyranoside were isolated from the leaves of the plant through bio-active guided fractionation. Both these compounds were screened against diarrhoea causative organisms (Echerichia coli, Shigella flexneri, Bacillus cereus and Staphylococcus aureus) and exhibiting minimum inhibitory concentrations ranging from 12.5 to 100 μg/ml. The findings from this research have generally justified the traditional use of this plant for the treatment of diarrhoea in this province.
- Full Text:
- Authors: Appidi, Jaipal Reddy
- Date: 2010
- Subjects: Sterculiaceae , Medicinal plants -- South Africa -- Eastern Cape , Diarrhea , Botany, Medical
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:11304 , http://hdl.handle.net/10353/259 , Sterculiaceae , Medicinal plants -- South Africa -- Eastern Cape , Diarrhea , Botany, Medical
- Description: Hermannia incana Cav. (Sterculiaceae), known as sweet yellow bells, is a medicinal plant used by the people of the Eastern Cape for the treatment of stomach-ache and diarrhoea. It has purgative and diaphoretic effects. It is a prostrate herb with yellow flowers and sparsely hairy and slightly glandular leaves, occurring in grassland and marshes in the Eastern Cape Province of South Africa. Based on the ethnomedical uses of this plant, the research project was designed to evaluate its antidiarrhoeal and toxicological properties. An ethnobotanical study of plants used for the treatment of diarrhoea in the Eastern Cape Province was carried out, using a questionnaire which was administered to herbalists, traditional healers and rural dwellers. This survey indicated a total of 17 plant species from 14 families. Elephantorrhiza elephantine (Burch.) Skeels, Hermannia incana Cav., Pelargonium reniforme Curt., Alepidea amatymbica Eckl. & Zeyh. and Bulbine latifolia (L.f.) Roem. et Schult. were the most frequently mentioned and highly recommended plants for the treatment of diarrhoea by both the traditional healers and rural dwellers. The root, bark and leaves are the common parts of plants used, while decoctions and infusions are the main methods of preparation. The agar dilution method was used to study the antimicrobial activity. The methanol extracts of the plant showed appreciable activity against Gram-positive and Gram-negative bacteria at concentrations ranging from 0.5 to 7.0 mg/ml. The acetone and water extracts of both the leaves and the roots showed moderate activity against Gram positive bacteria and less activity against Gram negative bacteria. All the extracts inhibited the growth of the fungi Aspergillus flavus, Aspergillus niger, and Mucor hiemalis with growth inhibition ranging from 54.31 percent to 96.67 percent at 0.1-10 mg/ml. None of the extracts suppressed the growth of Candida albicans at the maximum concentration (10 mg/ml) tested. iii In the in vivo antidiarrhoeal evaluation using Wistar rats, the aqueous extract at all the doses tested, significantly prolonged the time of induction of diarrhoea and also reduced the frequency of diarrhoeal episodes and fecal parameters (total number, number of wet, fresh and dry weight and water content of the faeces). The percentage inhibition of defecation and intestinal content (enteropooling) were increased in dose dependent manner. The doses also reduced the intestinal transit time of charcoal, masses and volumes of intestinal fluid (gastrointestinal motility). These results are indications of antidiarrhoeal property of H. incana leaf extract with the 600 mg/kg body weight of the extract being the most effective. In the toxicological evaluation using Wistar rats, the oral administration of the extract did not produce any significant effect on the liver and kidney body weight ratios, RBC, HB, PCV, MCV MCH, MCHC, RCDW, WBC, neutrophils, monocytes and basophils cholesterol, triacylglycerol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol and atherogenic index. The extract also did not affect the levels of sodium, potassium, chloride, inorganic phosphorus, urea, creatinine, total protein, globulin, albumin, total and conjugated bilirubin. The activities of alkaline phosphatase, gamma glutamyl transferase and alanine aminotransaminase in the serum were increased by the extract whereas aspartate aminotransaminase was decreased. The levels of LUC, platelets, lymphocytes and eosinophils were significantly affected at 600 mg/kg body weight. The available evidence in this study suggests that the extract of H. incana leaf is mild, parameter and dose specific. The structure and distribution of foliar appendages on the leaves of this plant were investigated with the JEOL (JSM-6390LV) scanning electron microscope (SEM). Both glandular and non-glandular trichomes were observed. Long stalked glandular trichomes were present on both the abaxial and adaxial surfaces while short stalked glandular trichomes were present only on the adaxial surface. Glandular trichomes were capitate while nonglandular trichomes were stellate with many arms. Energy dispersive X-ray spectroscopyiv SEM showed that Al, Ca, K, Na, Ti and Si were the major constituents of the crystals analyzed from the leaf surfaces. The phytochemical screening of H. incana revealed the presence of bioactive antidiarrhoeal agents such as alkaloids, tannins, saponins, phenolics, triterpenes, cardiac glycosides, flavonoids, cardenolides and dienolides. Two flavonoids, epicatechin and 3, 5, 7, 2’ tetra-hydroxy flavone-3- O--D-glucopyranoside were isolated from the leaves of the plant through bio-active guided fractionation. Both these compounds were screened against diarrhoea causative organisms (Echerichia coli, Shigella flexneri, Bacillus cereus and Staphylococcus aureus) and exhibiting minimum inhibitory concentrations ranging from 12.5 to 100 μg/ml. The findings from this research have generally justified the traditional use of this plant for the treatment of diarrhoea in this province.
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Evaluation of cover crop species for biomass production, weed suppression and maize yields under irrigation in the Eastern Cape Province, South Africa
- Authors: Musunda, Bothwell Zvidzai
- Date: 2010
- Subjects: Cover crops , Biomass energy -- South Africa -- Eastern Cape , No-tillage , Conservation of natural resources -- South Africa -- Eastern Cape , Agriculture -- South Africa -- Eastern Cape , Agricultural systems -- South Africa -- Eastern Cape , Weeds
- Language: English
- Type: Thesis , Masters , MSc Agric (Crop Science)
- Identifier: vital:11867 , http://hdl.handle.net/10353/347 , Cover crops , Biomass energy -- South Africa -- Eastern Cape , No-tillage , Conservation of natural resources -- South Africa -- Eastern Cape , Agriculture -- South Africa -- Eastern Cape , Agricultural systems -- South Africa -- Eastern Cape , Weeds
- Description: Achieving high biomass yields of cover crops has been a challenge to the success of Conservation Agriculture (CA) practices in the Eastern Cape (EC). A study was conducted to evaluate strategies for optimizing cover crop biomass production. Trials were carried out to screen summer and winter cover crops, as well as evaluate intercropping patterns and planting dates for biomass, weed suppression and subsequent maize yield under irrigation. Four summer legume cover crop species were evaluated under a Randomised Complete Block Design (RCBD) design. The cover crops were fertilized with 13.34 kg ha-1 of N, 20 kg ha-1 P and 26.66 kg ha-1 K. In the 2008/09 summer season a maize crop was superimposed on the 2007/08 screening trial under no-till. The crop was fertilized with 60 kg ha-1 of N. An intercropping trial was conducted over two seasons as a way of investigating the best way of incorporating cover crops into farmers cropping systems. This was done bearing in mind the limitation of resources such as land. The trial evaluated 3 factors laid as a 2 x 2 x 3 factorial arranged in a split-plot design. The main factor was cover crop planting date (planting at maize planting or 2 weeks after maize planting). The sub plot factor was intercropping pattern (strip intercropping and between row intercropping). A trial was also conducted to evaluate the effect of planting date (End of April and mid May) and four winter legume cover crop species on cover crop biomass, weed suppression and maize grain yield. The experiment was laid out as a Randomised Complete Block Design (RCBD) replicated 3 times. In the subsequent summer season a maize crop was superimposed on the winter trial to test the residual effects of the cover crop species. Another study was conducted to evaluate winter cereal cover crop species for biomass accumulation, weed suppression and subsequent maize grain yield. The cover crops as well as a weedy fallow control plot treatments were laid out as a Randomised Complete Block Design replicated 3 times. In the subsequent summer season a maize crop was superimposed on the site under no-till to evaluate the residual effect of the cover crops on maize. The results showed sunhemp, cowpea and lablab as the best cover crops with high biomass and weed suppression whilst mucuna was the least. Sunhemp consistently yielded higher cover biomass averaging 11200 kg ha-1 over the two seasons whilst mucuna had a consistently lowest average biomass yield of 4050 kg ha-1. These cover crops were above the critical 6 t ha-1 for effective weed suppression. There was a significant (p<0.01) relationship of cover crop dry weight and weed dry weight in both seasons. Subsequent maize grain yield was significantly higher in the sunhemp plots (64.2 %) than the weedy fallow plot. Mucuna, lablab and cowpea had maize grain yield increases of 16.6%, 33% and 43.2% respectively. Intercropping cover crops at maize planting yielded higher cover crop dry weights than a delay in intercropping cover crops. A delay in intercropping resulted in significantly higher average maize grain yield of 4700 kg ha-1 compared to intercropping at maize planting (3800 kg ha-1) and sole maize (4300 kg ha-1) over the two seasons. Strip intercropping also yielded higher (5000 kg ha- 1) average maize grain yield compared to row intercropping (3600 kg ha-1) and sole maize (4300 kg ha-1). There was a significant (p<0.05) relationship between cover crop dry weight in the 2007/08 season and maize grain yield in the 2008/09 season. Early planting grazing vetch gave the highest biomass yield of 8100 kg ha-1 whilst early planted red clover had the lowest biomass of 635 kg ha-1. Low weed dry weights were also obtained from the early planted grazing vetch as opposed to the other treatments. There was a significant (p<0.001) relationship of cover crop dry weight and weed dry weight. In the subsequent 2008/09 summer season early planted grazing vetch had the highest maize yield of 7500 kg ha-1 which was 56.3 % more than the weedy fallow plot had 4800 kg ha-1. The weedy fallow plot also had high weed infestation than the cover crop plots. There were significant (p<0.01) relationships between cover crop dry weight and maize grain yield, winter weed dry weight and maize grain yield and summer weed dry weight and maize grain yield. The results also showed triticale (13900 kg ha-1) as the best winter cover crop for biomass production. Italian ryegrass (6500 kg ha-1) produced the least amount of biomass. In The subsequent maize crop white oats gave highest maize grain yield (6369 kg ha-1) which was 33 % more than the weedy fallow plot (4784 kg ha- 1). There were also significant (p< 0.01) relationships of maize grain yield and winter weed dry weight, maize grain yield and summer growing weeds. The various studies demonstrated that there is opportunity for high biomass production under small scale farmers irrigated conditions using cover crops both in winter and summer. Best bet cover crops were sunhemp, cowpea and lablab for summer and triticale, white oats, barley, Italian ryegrass and grazing vetch for winter. Cover crops can also be incorporated into farmers cropping systems as sole crops or intercrops within the maize based cropping systems. Strip intercropping can be used by farmers as a way of introducing cover crops. Critical to achievement of high biomass is the time of planting cover crops with high biomass when planting is done early. A 2 week delay in strip intercropping cover crop into maize can be used as a way of incorporating cover crops into farmers cropping systems with minimal maize yield reduction.
- Full Text:
- Authors: Musunda, Bothwell Zvidzai
- Date: 2010
- Subjects: Cover crops , Biomass energy -- South Africa -- Eastern Cape , No-tillage , Conservation of natural resources -- South Africa -- Eastern Cape , Agriculture -- South Africa -- Eastern Cape , Agricultural systems -- South Africa -- Eastern Cape , Weeds
- Language: English
- Type: Thesis , Masters , MSc Agric (Crop Science)
- Identifier: vital:11867 , http://hdl.handle.net/10353/347 , Cover crops , Biomass energy -- South Africa -- Eastern Cape , No-tillage , Conservation of natural resources -- South Africa -- Eastern Cape , Agriculture -- South Africa -- Eastern Cape , Agricultural systems -- South Africa -- Eastern Cape , Weeds
- Description: Achieving high biomass yields of cover crops has been a challenge to the success of Conservation Agriculture (CA) practices in the Eastern Cape (EC). A study was conducted to evaluate strategies for optimizing cover crop biomass production. Trials were carried out to screen summer and winter cover crops, as well as evaluate intercropping patterns and planting dates for biomass, weed suppression and subsequent maize yield under irrigation. Four summer legume cover crop species were evaluated under a Randomised Complete Block Design (RCBD) design. The cover crops were fertilized with 13.34 kg ha-1 of N, 20 kg ha-1 P and 26.66 kg ha-1 K. In the 2008/09 summer season a maize crop was superimposed on the 2007/08 screening trial under no-till. The crop was fertilized with 60 kg ha-1 of N. An intercropping trial was conducted over two seasons as a way of investigating the best way of incorporating cover crops into farmers cropping systems. This was done bearing in mind the limitation of resources such as land. The trial evaluated 3 factors laid as a 2 x 2 x 3 factorial arranged in a split-plot design. The main factor was cover crop planting date (planting at maize planting or 2 weeks after maize planting). The sub plot factor was intercropping pattern (strip intercropping and between row intercropping). A trial was also conducted to evaluate the effect of planting date (End of April and mid May) and four winter legume cover crop species on cover crop biomass, weed suppression and maize grain yield. The experiment was laid out as a Randomised Complete Block Design (RCBD) replicated 3 times. In the subsequent summer season a maize crop was superimposed on the winter trial to test the residual effects of the cover crop species. Another study was conducted to evaluate winter cereal cover crop species for biomass accumulation, weed suppression and subsequent maize grain yield. The cover crops as well as a weedy fallow control plot treatments were laid out as a Randomised Complete Block Design replicated 3 times. In the subsequent summer season a maize crop was superimposed on the site under no-till to evaluate the residual effect of the cover crops on maize. The results showed sunhemp, cowpea and lablab as the best cover crops with high biomass and weed suppression whilst mucuna was the least. Sunhemp consistently yielded higher cover biomass averaging 11200 kg ha-1 over the two seasons whilst mucuna had a consistently lowest average biomass yield of 4050 kg ha-1. These cover crops were above the critical 6 t ha-1 for effective weed suppression. There was a significant (p<0.01) relationship of cover crop dry weight and weed dry weight in both seasons. Subsequent maize grain yield was significantly higher in the sunhemp plots (64.2 %) than the weedy fallow plot. Mucuna, lablab and cowpea had maize grain yield increases of 16.6%, 33% and 43.2% respectively. Intercropping cover crops at maize planting yielded higher cover crop dry weights than a delay in intercropping cover crops. A delay in intercropping resulted in significantly higher average maize grain yield of 4700 kg ha-1 compared to intercropping at maize planting (3800 kg ha-1) and sole maize (4300 kg ha-1) over the two seasons. Strip intercropping also yielded higher (5000 kg ha- 1) average maize grain yield compared to row intercropping (3600 kg ha-1) and sole maize (4300 kg ha-1). There was a significant (p<0.05) relationship between cover crop dry weight in the 2007/08 season and maize grain yield in the 2008/09 season. Early planting grazing vetch gave the highest biomass yield of 8100 kg ha-1 whilst early planted red clover had the lowest biomass of 635 kg ha-1. Low weed dry weights were also obtained from the early planted grazing vetch as opposed to the other treatments. There was a significant (p<0.001) relationship of cover crop dry weight and weed dry weight. In the subsequent 2008/09 summer season early planted grazing vetch had the highest maize yield of 7500 kg ha-1 which was 56.3 % more than the weedy fallow plot had 4800 kg ha-1. The weedy fallow plot also had high weed infestation than the cover crop plots. There were significant (p<0.01) relationships between cover crop dry weight and maize grain yield, winter weed dry weight and maize grain yield and summer weed dry weight and maize grain yield. The results also showed triticale (13900 kg ha-1) as the best winter cover crop for biomass production. Italian ryegrass (6500 kg ha-1) produced the least amount of biomass. In The subsequent maize crop white oats gave highest maize grain yield (6369 kg ha-1) which was 33 % more than the weedy fallow plot (4784 kg ha- 1). There were also significant (p< 0.01) relationships of maize grain yield and winter weed dry weight, maize grain yield and summer growing weeds. The various studies demonstrated that there is opportunity for high biomass production under small scale farmers irrigated conditions using cover crops both in winter and summer. Best bet cover crops were sunhemp, cowpea and lablab for summer and triticale, white oats, barley, Italian ryegrass and grazing vetch for winter. Cover crops can also be incorporated into farmers cropping systems as sole crops or intercrops within the maize based cropping systems. Strip intercropping can be used by farmers as a way of introducing cover crops. Critical to achievement of high biomass is the time of planting cover crops with high biomass when planting is done early. A 2 week delay in strip intercropping cover crop into maize can be used as a way of incorporating cover crops into farmers cropping systems with minimal maize yield reduction.
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Evaluation of plant extracts used in ethno-veterinary control of gastro-intestinal parasites in village chickens in the Eastern Cape Province of South Africa
- Authors: Mwale, Marizvikuru
- Date: 2010
- Subjects: Chickens -- Diseases -- South Africa -- Eastern Cape , Parasites -- South Africa -- Eastern Cape , Traditional medicine -- South Africa -- Eastern Cape , Chickens -- Parasites -- Control , Sustainable agriculture -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , PhD (Animal Science)
- Identifier: vital:11177 , http://hdl.handle.net/10353/d1001021 , Chickens -- Diseases -- South Africa -- Eastern Cape , Parasites -- South Africa -- Eastern Cape , Traditional medicine -- South Africa -- Eastern Cape , Chickens -- Parasites -- Control , Sustainable agriculture -- South Africa -- Eastern Cape
- Full Text: false
- Authors: Mwale, Marizvikuru
- Date: 2010
- Subjects: Chickens -- Diseases -- South Africa -- Eastern Cape , Parasites -- South Africa -- Eastern Cape , Traditional medicine -- South Africa -- Eastern Cape , Chickens -- Parasites -- Control , Sustainable agriculture -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , PhD (Animal Science)
- Identifier: vital:11177 , http://hdl.handle.net/10353/d1001021 , Chickens -- Diseases -- South Africa -- Eastern Cape , Parasites -- South Africa -- Eastern Cape , Traditional medicine -- South Africa -- Eastern Cape , Chickens -- Parasites -- Control , Sustainable agriculture -- South Africa -- Eastern Cape
- Full Text: false
Evaluation of water service rendering in the Amathole District Municipality
- Authors: Mqolo, Abner Zamindawo
- Date: 2010
- Subjects: Municipal government -- South Africa -- Eastern Cape , Municipal services -- South Africa -- Eastern Cape , Water-supply -- South Africa -- Eastern Cape , Municipal water supply -- South Africa -- Eastern Cape , Water-supply, Rural -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MPA
- Identifier: vital:11639 , http://hdl.handle.net/10353/d1001248 , Municipal government -- South Africa -- Eastern Cape , Municipal services -- South Africa -- Eastern Cape , Water-supply -- South Africa -- Eastern Cape , Municipal water supply -- South Africa -- Eastern Cape , Water-supply, Rural -- South Africa -- Eastern Cape
- Description: The rural areas of Amathole district municipality continue to experience difficulty in accessing water services. The people experience problems despite the fact that the Amathole district municipality, since 2003 has been made a water service authority in its municipal area, which consists of eight local municipalities, namely; Mnquma, Mbashe, Nkonkobe, Amahlathi, Great Kei, Ngqushwa, Nxuba, and Buffalo City. With the water service authority powers devolved from national government to the district municipalities the intention was to speed service delivery. This study investigates the causes of the delays in water service delivery experienced in rural areas of this district municipality. The Buffalo City local municipality is excluded in the study because Buffalo City has as well been given the responsibility of being the water service authority in its municipal area. This study used the questionnaires as data collection tool, and it was distributed to these respondents; chief officials, councilors, and citizens. Due to vastness of the target population sampling was used to reduce the bulkiness of the data. The questionnaire content is based on the phases of the systems theory to see if the policy making processes of the Amathole district municipality are carried out in accordance with the systems theory. The study has found that the citizens are not adequately involved in all the policy processes including the policy analysis and evaluation. This has been found to be a contributory factor in the ineffectiveness of the municipality water service delivery.The spheres of government that operate in silos compromised policy analysis and evaluation of the municipality, and disjuncture of the delivery programs of the spheres and state enterprises caused a huge service delivery challenges for this municipality. The study has confirmed that the Amathole district municipality is experiencing problems, delays, and challenges that make it to be ineffective as a water service authority.
- Full Text:
- Authors: Mqolo, Abner Zamindawo
- Date: 2010
- Subjects: Municipal government -- South Africa -- Eastern Cape , Municipal services -- South Africa -- Eastern Cape , Water-supply -- South Africa -- Eastern Cape , Municipal water supply -- South Africa -- Eastern Cape , Water-supply, Rural -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MPA
- Identifier: vital:11639 , http://hdl.handle.net/10353/d1001248 , Municipal government -- South Africa -- Eastern Cape , Municipal services -- South Africa -- Eastern Cape , Water-supply -- South Africa -- Eastern Cape , Municipal water supply -- South Africa -- Eastern Cape , Water-supply, Rural -- South Africa -- Eastern Cape
- Description: The rural areas of Amathole district municipality continue to experience difficulty in accessing water services. The people experience problems despite the fact that the Amathole district municipality, since 2003 has been made a water service authority in its municipal area, which consists of eight local municipalities, namely; Mnquma, Mbashe, Nkonkobe, Amahlathi, Great Kei, Ngqushwa, Nxuba, and Buffalo City. With the water service authority powers devolved from national government to the district municipalities the intention was to speed service delivery. This study investigates the causes of the delays in water service delivery experienced in rural areas of this district municipality. The Buffalo City local municipality is excluded in the study because Buffalo City has as well been given the responsibility of being the water service authority in its municipal area. This study used the questionnaires as data collection tool, and it was distributed to these respondents; chief officials, councilors, and citizens. Due to vastness of the target population sampling was used to reduce the bulkiness of the data. The questionnaire content is based on the phases of the systems theory to see if the policy making processes of the Amathole district municipality are carried out in accordance with the systems theory. The study has found that the citizens are not adequately involved in all the policy processes including the policy analysis and evaluation. This has been found to be a contributory factor in the ineffectiveness of the municipality water service delivery.The spheres of government that operate in silos compromised policy analysis and evaluation of the municipality, and disjuncture of the delivery programs of the spheres and state enterprises caused a huge service delivery challenges for this municipality. The study has confirmed that the Amathole district municipality is experiencing problems, delays, and challenges that make it to be ineffective as a water service authority.
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Geographies of juvenile crime: a study of crime in selected high schools in East London, South Africa
- Authors: Ladokun, Ayodele Olanrewaju
- Date: 2010
- Subjects: Juvenile delinquency -- South Africa -- East London , School violence -- South Africa -- East London , Education, Secondary -- South Africa -- East London , High schools -- South Africa -- East London , School management and organization -- South Africa -- East London , Crime--South Africa -- East London
- Language: English
- Type: Thesis , Masters , MSc (Geography)
- Identifier: vital:11507 , http://hdl.handle.net/10353/345 , Juvenile delinquency -- South Africa -- East London , School violence -- South Africa -- East London , Education, Secondary -- South Africa -- East London , High schools -- South Africa -- East London , School management and organization -- South Africa -- East London , Crime--South Africa -- East London
- Description: Youth crime has been and still is a social problem in South Africa. It is a problem that shakes the very fabric of the society. The problem with the youth in modern society is both a national concern and an important subject for academic study. High school environments are where youths converge for learning purposes, but they have also turned to hotspots for crime. Different theories on explanations for high school crime have been developed over time. This particular study, conducted in 2008, adopts the criminal opportunity theory to study the social, economic and the demographic characteristics of selected environments in which high schools are located to determine significant factors that are conducive for high schools to be crime hotspots. Three schools were selected in different neighbourhoods in East London for the study. The study used an intensive case design technique to conduct the research. Different characteristics of the communities in which the schools that were studied were located showed different crime pattern. The Law enforcement agencies also realize these differences and they try to address crime issues in various communities in the study areas individually
- Full Text:
- Authors: Ladokun, Ayodele Olanrewaju
- Date: 2010
- Subjects: Juvenile delinquency -- South Africa -- East London , School violence -- South Africa -- East London , Education, Secondary -- South Africa -- East London , High schools -- South Africa -- East London , School management and organization -- South Africa -- East London , Crime--South Africa -- East London
- Language: English
- Type: Thesis , Masters , MSc (Geography)
- Identifier: vital:11507 , http://hdl.handle.net/10353/345 , Juvenile delinquency -- South Africa -- East London , School violence -- South Africa -- East London , Education, Secondary -- South Africa -- East London , High schools -- South Africa -- East London , School management and organization -- South Africa -- East London , Crime--South Africa -- East London
- Description: Youth crime has been and still is a social problem in South Africa. It is a problem that shakes the very fabric of the society. The problem with the youth in modern society is both a national concern and an important subject for academic study. High school environments are where youths converge for learning purposes, but they have also turned to hotspots for crime. Different theories on explanations for high school crime have been developed over time. This particular study, conducted in 2008, adopts the criminal opportunity theory to study the social, economic and the demographic characteristics of selected environments in which high schools are located to determine significant factors that are conducive for high schools to be crime hotspots. Three schools were selected in different neighbourhoods in East London for the study. The study used an intensive case design technique to conduct the research. Different characteristics of the communities in which the schools that were studied were located showed different crime pattern. The Law enforcement agencies also realize these differences and they try to address crime issues in various communities in the study areas individually
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Immunological and molecular characterization of Cryptosporidium species in HIV-Positive and HIV-Negative diarrhoea patients in the Nkonkobe Municipality of the Eastern Cape Province of South Africa: a pilot study
- Authors: Etinosa, Omoruyi Beauty
- Date: 2010
- Subjects: Protozoa, Pathogenic , Pathogenic microorganisms -- Detection , Medical microbiology , HIV-positive persons , Cryptosporidium , Diarrhea , HIV-infections
- Language: English
- Type: Thesis , Masters , MSc (Biochemistry)
- Identifier: vital:11252 , http://hdl.handle.net/10353/392 , Protozoa, Pathogenic , Pathogenic microorganisms -- Detection , Medical microbiology , HIV-positive persons , Cryptosporidium , Diarrhea , HIV-infections
- Description: Cryptosporidiosis is an infection caused by Cryptosporidium; a protozoan parasite that infects the gastrointestinal tract. The infection is of major public health concern in both developed and developing countries. Faecal samples were collected from 160 in-patient adults, with complaint of diarrhoea, admitted at Victoria hospital in Alice, Nkonkobe Municipality. Twenty apparently healthy subjects were included as controls. All diarrhoea positive patients were interviewed to record socio-demographic information, water supply and animal contact. Initial screening was carried out by microscopy and ELISA to detect positive Cryptosporidium. Genomic DNA was extracted from microscopically positive samples and a PCR reaction was perform to amplify the (18S) SSUrRNA gene for further identification and epidemiology of Cryptosporidium. Data were analysed using Pearson‘s χ2 and Fisher‘s exact test to assess the univariate association between Cryptosporidium infection and the possible risk factors. Of the 180 subjects screened for cryptosporidial infection, Cryptosporidium antigen was detected in 122 giving an overall prevalence of 67.8 percent. In HIV-positive diarrhoea patients, prevalence increased with ages; between 31-43 (mean age 36.5 yr) and 70-82 (mean age 75.8 yr) had a higher prevalence (100 percent) of the antigen than 18-30 (mean age 23.2 yr) and 83-95 (mean age 88.8 yr) (50.0 percent) in HIV-positive diarrhoea patients (P > 0.05). In HIV-negative diarrhoea patients, prevalence was highest in the 18-30 (mean age 23.2 yr) (87.5 percent) and least (35.7 percent) in those aged 83-95 (mean age 88.8 yr) (P > 0.05). Cryptosporidium antigen was higher in females than in males. Of 115 females (mean age 46.7yr) who participated in the study, antigen was detected in 90 (78.2 percent) against 32 (71.1 percent) of 45 males (mean age 42.6yr). None of the 20 apparently healthy control subjects was found to be infected with Cryptosporidium. Cryptosporidium was detected in 27 HIV-positive and 97 HIV-negative diarrhoea patients by any one of the techniques. Antigen detection by ELISA 14 showed the highest positivity 96 (76.8 percent) in HIV- negative and 26 (74.3 percent) in HIV- positive diarrhoea patients. PCR detected eighty-nine (71.2 percent) cases in HIV-negative and 23 (65.7 percent) in HIV-positive patients with diarrhoea. Only 13 (37.1 percent) HIV-positive and 34 (27.2 percent) HIV-negative diarrhoea patients were found positive for Cryptosporidium by modified ZN. No significant difference was observed in sensitivity of antigen detection by ELISA and PCR (96.9 percent) in HIV-negative diarrhoea patients, respectively. Specificity of the staining technique was 88.9 percent in HIV-positive and 96.6 percent in HIV-negative diarrhoea patients. No significant difference was found in specificity of antigen detection by ELISA and PCR in HIV-positive and HIV-negative diarrhoea patients, respectively. Positive predictive value of ZN staining in both HIV-positive and HIV-negative diarrhoea patients (92.3 and 96.9 percent) was statistically higher than ELISA and PCR. No significant difference was observed in negative predictive value of ZN technique for detection of Cryptosporidium between HIV-positive and HIV- negative diarrhoea patients. Differences found in prevalence rates due to water source, suggest that the high infection rates of specific groups are associated with their exposure to the contaminated water supply. The results indicate that Cryptosporidium infection is highly prevalent in adult faecal specimens in the Nkonkobe Municipality, an indication of active infection that is likely to emerge as major human pathogen in this location due to socioeconomic changes which favour transmission. However, sequencing analysis is required to differentiate between Cryptosporidium genotypes in the various outbreaks
- Full Text:
- Authors: Etinosa, Omoruyi Beauty
- Date: 2010
- Subjects: Protozoa, Pathogenic , Pathogenic microorganisms -- Detection , Medical microbiology , HIV-positive persons , Cryptosporidium , Diarrhea , HIV-infections
- Language: English
- Type: Thesis , Masters , MSc (Biochemistry)
- Identifier: vital:11252 , http://hdl.handle.net/10353/392 , Protozoa, Pathogenic , Pathogenic microorganisms -- Detection , Medical microbiology , HIV-positive persons , Cryptosporidium , Diarrhea , HIV-infections
- Description: Cryptosporidiosis is an infection caused by Cryptosporidium; a protozoan parasite that infects the gastrointestinal tract. The infection is of major public health concern in both developed and developing countries. Faecal samples were collected from 160 in-patient adults, with complaint of diarrhoea, admitted at Victoria hospital in Alice, Nkonkobe Municipality. Twenty apparently healthy subjects were included as controls. All diarrhoea positive patients were interviewed to record socio-demographic information, water supply and animal contact. Initial screening was carried out by microscopy and ELISA to detect positive Cryptosporidium. Genomic DNA was extracted from microscopically positive samples and a PCR reaction was perform to amplify the (18S) SSUrRNA gene for further identification and epidemiology of Cryptosporidium. Data were analysed using Pearson‘s χ2 and Fisher‘s exact test to assess the univariate association between Cryptosporidium infection and the possible risk factors. Of the 180 subjects screened for cryptosporidial infection, Cryptosporidium antigen was detected in 122 giving an overall prevalence of 67.8 percent. In HIV-positive diarrhoea patients, prevalence increased with ages; between 31-43 (mean age 36.5 yr) and 70-82 (mean age 75.8 yr) had a higher prevalence (100 percent) of the antigen than 18-30 (mean age 23.2 yr) and 83-95 (mean age 88.8 yr) (50.0 percent) in HIV-positive diarrhoea patients (P > 0.05). In HIV-negative diarrhoea patients, prevalence was highest in the 18-30 (mean age 23.2 yr) (87.5 percent) and least (35.7 percent) in those aged 83-95 (mean age 88.8 yr) (P > 0.05). Cryptosporidium antigen was higher in females than in males. Of 115 females (mean age 46.7yr) who participated in the study, antigen was detected in 90 (78.2 percent) against 32 (71.1 percent) of 45 males (mean age 42.6yr). None of the 20 apparently healthy control subjects was found to be infected with Cryptosporidium. Cryptosporidium was detected in 27 HIV-positive and 97 HIV-negative diarrhoea patients by any one of the techniques. Antigen detection by ELISA 14 showed the highest positivity 96 (76.8 percent) in HIV- negative and 26 (74.3 percent) in HIV- positive diarrhoea patients. PCR detected eighty-nine (71.2 percent) cases in HIV-negative and 23 (65.7 percent) in HIV-positive patients with diarrhoea. Only 13 (37.1 percent) HIV-positive and 34 (27.2 percent) HIV-negative diarrhoea patients were found positive for Cryptosporidium by modified ZN. No significant difference was observed in sensitivity of antigen detection by ELISA and PCR (96.9 percent) in HIV-negative diarrhoea patients, respectively. Specificity of the staining technique was 88.9 percent in HIV-positive and 96.6 percent in HIV-negative diarrhoea patients. No significant difference was found in specificity of antigen detection by ELISA and PCR in HIV-positive and HIV-negative diarrhoea patients, respectively. Positive predictive value of ZN staining in both HIV-positive and HIV-negative diarrhoea patients (92.3 and 96.9 percent) was statistically higher than ELISA and PCR. No significant difference was observed in negative predictive value of ZN technique for detection of Cryptosporidium between HIV-positive and HIV- negative diarrhoea patients. Differences found in prevalence rates due to water source, suggest that the high infection rates of specific groups are associated with their exposure to the contaminated water supply. The results indicate that Cryptosporidium infection is highly prevalent in adult faecal specimens in the Nkonkobe Municipality, an indication of active infection that is likely to emerge as major human pathogen in this location due to socioeconomic changes which favour transmission. However, sequencing analysis is required to differentiate between Cryptosporidium genotypes in the various outbreaks
- Full Text:
Impact of access to free basic electricity on households' poverty in Buffalo City Municipality in the Eastern Cape
- Authors: Mvondo, Jephthe M
- Date: 2010
- Subjects: Household surveys -- South Africa -- Eastern Cape , Poverty -- South Africa -- Eastern Cape , Quality of life -- South Africa -- Eastern Cape , Electric utilities -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , M Soc Sc (Dev)
- Identifier: vital:11419 , http://hdl.handle.net/10353/280 , Household surveys -- South Africa -- Eastern Cape , Poverty -- South Africa -- Eastern Cape , Quality of life -- South Africa -- Eastern Cape , Electric utilities -- South Africa -- Eastern Cape
- Description: The study was premised on the truism that men have historically served in higher echelons of organizational management structures and women are under-represented. The principal objective was to explore the constraints faced by women in accessing higher leadership and senior management positions in public, private and non-governmental organisations in Zimbabwe. This study adopted the triangulation method, that is, qualitative and quantitative approaches. These mixed research methods, were upgraded by the feminist research methodologies, thereby making a contribution in the field of research. The study found out that the constraints that mostly hinder women from accessing leadership and senior management positions in public, private and NGOs were cultural practices, which represent levels of power and control that in turn hinder reforms; and women's socialisation into feminised roles. The study also found out that in most organisations, most females work under male leadership, and this traditional organisational culture, needs to be deconstructed and reversed in order to achieve gender equality. The study recommended for a human centric and integrated organizational management strategy for public, private and NGOs in Zimbabwe. The adoption of a human centric and integrated management approach should aim at gender equity and reduce women's under-representation. A human centred organizational culture has to be practiced, that would create organisational ethos that guide organizational management. An integrated organizational management approach should integrate all systems and processes into one complete framework, enabling people to work as a single unit, unified by organizational goals, shared vision and common values. The system should depend on a balanced mix of the masculine and feminine attributes. The approach should put its weight towards adoption of measures to attract, advance and empower women so as to benefit from their qualifications, experience and talent in a highly competitive environment.
- Full Text:
- Authors: Mvondo, Jephthe M
- Date: 2010
- Subjects: Household surveys -- South Africa -- Eastern Cape , Poverty -- South Africa -- Eastern Cape , Quality of life -- South Africa -- Eastern Cape , Electric utilities -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , M Soc Sc (Dev)
- Identifier: vital:11419 , http://hdl.handle.net/10353/280 , Household surveys -- South Africa -- Eastern Cape , Poverty -- South Africa -- Eastern Cape , Quality of life -- South Africa -- Eastern Cape , Electric utilities -- South Africa -- Eastern Cape
- Description: The study was premised on the truism that men have historically served in higher echelons of organizational management structures and women are under-represented. The principal objective was to explore the constraints faced by women in accessing higher leadership and senior management positions in public, private and non-governmental organisations in Zimbabwe. This study adopted the triangulation method, that is, qualitative and quantitative approaches. These mixed research methods, were upgraded by the feminist research methodologies, thereby making a contribution in the field of research. The study found out that the constraints that mostly hinder women from accessing leadership and senior management positions in public, private and NGOs were cultural practices, which represent levels of power and control that in turn hinder reforms; and women's socialisation into feminised roles. The study also found out that in most organisations, most females work under male leadership, and this traditional organisational culture, needs to be deconstructed and reversed in order to achieve gender equality. The study recommended for a human centric and integrated organizational management strategy for public, private and NGOs in Zimbabwe. The adoption of a human centric and integrated management approach should aim at gender equity and reduce women's under-representation. A human centred organizational culture has to be practiced, that would create organisational ethos that guide organizational management. An integrated organizational management approach should integrate all systems and processes into one complete framework, enabling people to work as a single unit, unified by organizational goals, shared vision and common values. The system should depend on a balanced mix of the masculine and feminine attributes. The approach should put its weight towards adoption of measures to attract, advance and empower women so as to benefit from their qualifications, experience and talent in a highly competitive environment.
- Full Text:
Impact of in-field rainwater harvesting technology on household food security: a case of Guquka and Khayalethu villages in Central Eastern Cape Province
- Hlanganise, Yoliswa Happiness
- Authors: Hlanganise, Yoliswa Happiness
- Date: 2010
- Subjects: Water consumption -- South Africa -- Eastern Cape , Poverty -- South Africa -- Eastern Cape , Water harvesting -- South Africa -- Eastern Cape , Food supply -- South Africa -- Eastern Cape , Sustainable agriculture -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11179 , http://hdl.handle.net/10353/352 , Water consumption -- South Africa -- Eastern Cape , Poverty -- South Africa -- Eastern Cape , Water harvesting -- South Africa -- Eastern Cape , Food supply -- South Africa -- Eastern Cape , Sustainable agriculture -- South Africa -- Eastern Cape
- Description: The aim of this investigation was to assess the impact of the In-Field Rainwater Harvesting technology on household food security in the study area. The study was conducted in Nkonkobe Local Municipality of the Amathole District Municipality in central Eastern Cape Province. The areas under investigation are Guquka and Khayaletu villages of the Thyume Valley, which is located about 30 kilometres north of Alice. The method used to assess the impact of the IRWH on household food security was a pair wise comparison method. During September 2009, there were 60 (34 in Guquka and 26 in Khayaletu) households who adopted the technology in home gardens. In order to get a clear picture of the impact of the technology on food security, a decision was taken to assess both the project members and non-project members, hence the pairwise comparison method. The non-project members (also 60 households) were selected randomly from those who were interviewed during the situation analysis in 2004. Five indicators were used to assess household food security. These were household income, expenditure on food, diet diversity, energy-protein intakes, and micro-nutrient intakes (Vitamin A, C and Iron). The income and expenditure data were collected from the 120 households. However, the detailed food data were collected from selected cases from both groups at different times (seasons) of the year. A case study approach was employed in data collection. A total of 12 cases (six households per village) were selected for this investigation. These were selected mainly according to the degree of poverty. The total of six households from each village comprised three project members and three non-members i.e. one from each poverty class (non- poor, poor and ultra-poor) in both categories. The data on the kinds of food products consumed by households was gathered using the food account method (FAM). The food consumed was then analysed for nutrient adequacy. The main findings of this investigation show the IRWH technology to have a positive impact on food security and nutrition of the project members. The technology made significant contributions to the amount of energy and vitamins A and C consumed by households especially during wet seasons. Substantial contributions of garden produce were noted among the project members. However, these contributions were not enough to ensure household food security. The results indicate that there are nutritional problems in the study area. Firstly, there is protein- v energy malnutrition mainly affecting the poor and the ultra-poor households. Secondly, there is hidden hunger affecting all poverty categories, even the non-poor households. This is mainly demonstrated by poor diet quality i.e. diet that lacks essential nutrients identified
- Full Text:
- Authors: Hlanganise, Yoliswa Happiness
- Date: 2010
- Subjects: Water consumption -- South Africa -- Eastern Cape , Poverty -- South Africa -- Eastern Cape , Water harvesting -- South Africa -- Eastern Cape , Food supply -- South Africa -- Eastern Cape , Sustainable agriculture -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11179 , http://hdl.handle.net/10353/352 , Water consumption -- South Africa -- Eastern Cape , Poverty -- South Africa -- Eastern Cape , Water harvesting -- South Africa -- Eastern Cape , Food supply -- South Africa -- Eastern Cape , Sustainable agriculture -- South Africa -- Eastern Cape
- Description: The aim of this investigation was to assess the impact of the In-Field Rainwater Harvesting technology on household food security in the study area. The study was conducted in Nkonkobe Local Municipality of the Amathole District Municipality in central Eastern Cape Province. The areas under investigation are Guquka and Khayaletu villages of the Thyume Valley, which is located about 30 kilometres north of Alice. The method used to assess the impact of the IRWH on household food security was a pair wise comparison method. During September 2009, there were 60 (34 in Guquka and 26 in Khayaletu) households who adopted the technology in home gardens. In order to get a clear picture of the impact of the technology on food security, a decision was taken to assess both the project members and non-project members, hence the pairwise comparison method. The non-project members (also 60 households) were selected randomly from those who were interviewed during the situation analysis in 2004. Five indicators were used to assess household food security. These were household income, expenditure on food, diet diversity, energy-protein intakes, and micro-nutrient intakes (Vitamin A, C and Iron). The income and expenditure data were collected from the 120 households. However, the detailed food data were collected from selected cases from both groups at different times (seasons) of the year. A case study approach was employed in data collection. A total of 12 cases (six households per village) were selected for this investigation. These were selected mainly according to the degree of poverty. The total of six households from each village comprised three project members and three non-members i.e. one from each poverty class (non- poor, poor and ultra-poor) in both categories. The data on the kinds of food products consumed by households was gathered using the food account method (FAM). The food consumed was then analysed for nutrient adequacy. The main findings of this investigation show the IRWH technology to have a positive impact on food security and nutrition of the project members. The technology made significant contributions to the amount of energy and vitamins A and C consumed by households especially during wet seasons. Substantial contributions of garden produce were noted among the project members. However, these contributions were not enough to ensure household food security. The results indicate that there are nutritional problems in the study area. Firstly, there is protein- v energy malnutrition mainly affecting the poor and the ultra-poor households. Secondly, there is hidden hunger affecting all poverty categories, even the non-poor households. This is mainly demonstrated by poor diet quality i.e. diet that lacks essential nutrients identified
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Implications of a currency board arrangement for the Zimbabwean economy: the lessons of experience
- Authors: Ndlovu, Edwin
- Date: 2010
- Subjects: Economic indicators , Inflation targeting , Foreign exchange
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/26492 , vital:65480
- Description: Inflation is one of the most important factors for gauging the health of the economy. For production, employment and trade to take place, it is crucial that inflation be low and stable. This study analyses the implications of a currency board system in a hyperinflationary economy, using quarterly Zimbabwean data covering the period 1995 to 2008.An empirical model linking inflation to its identified theoretical determinants is specified. The study employs a cointegration and a vector error correction (VEC) modeling, to provide robust long run and short run dynamic effects of hyper inflation on the economy. The empirical findings reveal a strong significant relationship between inflation and government deficit, expected inflation, money supply growth and the exchange rate. These results corroborate the theoretical predictions and the previous findings that most hyperinflations are deficit-induced. The study thus suggests an implementation of a currency board arrangement for Zimbabwe to eradicate hyperinflation based on its link with exchange rate, money supply and government deficit. A currency board restrains the tendency by most central banks to create money to finance government deficits, and reduces expectations of rising inflation through its instantaneous credibility in reducing inflation. , Thesis (MCom) -- Faculty of Management and Commerce, 2010
- Full Text:
- Authors: Ndlovu, Edwin
- Date: 2010
- Subjects: Economic indicators , Inflation targeting , Foreign exchange
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/26492 , vital:65480
- Description: Inflation is one of the most important factors for gauging the health of the economy. For production, employment and trade to take place, it is crucial that inflation be low and stable. This study analyses the implications of a currency board system in a hyperinflationary economy, using quarterly Zimbabwean data covering the period 1995 to 2008.An empirical model linking inflation to its identified theoretical determinants is specified. The study employs a cointegration and a vector error correction (VEC) modeling, to provide robust long run and short run dynamic effects of hyper inflation on the economy. The empirical findings reveal a strong significant relationship between inflation and government deficit, expected inflation, money supply growth and the exchange rate. These results corroborate the theoretical predictions and the previous findings that most hyperinflations are deficit-induced. The study thus suggests an implementation of a currency board arrangement for Zimbabwe to eradicate hyperinflation based on its link with exchange rate, money supply and government deficit. A currency board restrains the tendency by most central banks to create money to finance government deficits, and reduces expectations of rising inflation through its instantaneous credibility in reducing inflation. , Thesis (MCom) -- Faculty of Management and Commerce, 2010
- Full Text:
Improving Productivity of Maize-based Smallholder Irrigated Cropping Systems: A Case Study of Zanyokwe Irrigation Scheme, Eastern Cape, South Africa
- Authors: Fanadzo, Morris
- Date: 2010
- Subjects: Farms, Small -- South Africa -- Eastern Cape Crop yields -- South Africa -- Eastern Cape Agricultural productivity -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/11009 , vital:36450
- Description: Smallholder irrigation schemes (SIS) in South Africa have performed poorly and failed to achieve the development objectives of sustaining rural livelihoods by increasing crop production and income. Limited knowledge of crop production among farmers is one constraint to improved crop productivity and, yet little research has been carried out to relate agronomic practices to productivity. This study was aimed at identifying strategies to improve the productivity of maize-based smallholder irrigated cropping systems in South Africa, using Zanyokwe irrigation scheme (ZIS) in the Eastern Cape Province as a case study. The research design was emergent, developed progressively as influenced by the progressive analyses that were made. The research work involved two main phases: exploratory studies and refinement on-farm experiments for testing technologies as informed by the exploratory studies. Exploratory studies were aimed at describing farmer crop production practices in major crop enterprises and identifying and prioritizing major agronomic yield constraints. Findings indicated that the overall performance of the cropping systems was poor as evidenced by low overall yields of < 25% of the potential in maize and butternut. Poor management of weeds, soil fertility, plant populations and water, late planting and poor cultivar choice were the most important yield constraints. The average cropping intensity achieved by farmers was only 48%. New hybrids yielded 50 - 65% higher grain than the cultivars commonly grown by farmers. However, farmers favoured their traditional cultivars, as they preferred green maize production as opposed to dry grains. As a result of these findings, focused research was designed on options for iii improving green maize production, soil fertility, crop stand and weed management in crop production. On-farm trials were, therefore, designed to (1) compare the response to nitrogen (N) rate of direct seeded and transplanted maize; (2) evaluate comparative performance of direct seeded and transplanted green maize under farmer management, and to work out the economics of transplanting; (3) investigate the effects of row spacing and atrazine dosage on weed dynamics maize yield; (4) determine the effects of inter-row spacing and plant population on weed dynamics and maize yield; and (5) investigate the effects of pre-plant weed control, N rate and plant population on weed dynamics and butternut yield. Maize transplanting improved crop stand, had earlier maturity and yielded higher at lower N rates compared to direct seeding for both green and grain maize. Total costs that varied were higher by R3 565 ha-1 for transplanted maize compared to direct-seeded maize, but the net benefits from transplanting were also much higher by R8 773 ha-1. Farmers favoured transplanting, citing bigger cobs, early maturity and the absence of seedling damage by birds, when maize was transplanted. However, a follow-up survey conducted during the subsequent year indicated that five of the six farmers abandoned transplanting, citing shortage of labour and high cost of commercially produced seedlings. It was concluded that transplanting is unlikely to be adopted unless the labour intensiveness of manual transplanting can be solved. Increasing atrazine dosage from a third of the label recommended dosage (LRD) and reducing row spacing from 90 to 45 cm resulted in an increase in weed mortality. A 100% kill of annual broadleaf weeds was possible while iv perennial grasses and the annual broadleaf weed, Oxalis latifolia, could not be controlled even at the LRD. However, improved weed mortality with increase in atrazine dosage and/or narrow rows did not translate into improved maize productivity. In butternut, pre-plant weed control resulted in a six-fold decrease in weed biomass and a 100% increase in fruit yield. These findings demonstrated the possibility of incorporation of reduced herbicide dosages and narrow rows to achieve adequate weed control and optimise on maize yields in smallholder farming systems. The results also suggested that pre-plant weed control is one of the pre-requisite to successful butternut production in SIS in South Africa. Increasing maize population from 40 000 to 60 000 plants ha-1 resulted in a 30% grain yield increase, but decreased length of cobs. Row spacing had no effect on maize yield at 40 000 plants ha-1, but at 60 000 plants ha-1 45 cm rows resulted in 11% higher grain yield (12 547 kg ha-1) than 90 cm rows (11 288 kg ha-1). Butternut yield increased significantly (p < 0.01) with increase in plant population and N rate. The optimum butternut population and N rate were estimated at 25 000 plants ha-1 and 120 kg N ha-1, respectively. Pre-plant weed control in butternut resulted in a six-fold decrease in weed biomass. Increasing butternut planting density from 10 000 to 30 000 plants ha-1 decreased weed biomass by 47%. No marketable fruits were obtained when planting was done without prior weed control. This result suggest that application of non-selective herbicide before planting is one technique that can be used by farmers as part of integrated weed management to give the crop a competitive advantage in the early growth stages before the plants start to produce vines. Yield increased significantly (p < 0.01) with increase in plant density and N rate. The optimum plant density and N rate were estimated at 25 000 plants ha-1 and 120 kg N ha-1, respectively. These findings emphasise the need to take into consideration production practices by farmers as a basis to build up skills in the management of crop enterprises and the farm as a viable business in any efforts to improve on the performance of SIS in South Africa. Future research should concentrate on labour-saving sustainable production technologies for SIS in South Africa.
- Full Text:
- Authors: Fanadzo, Morris
- Date: 2010
- Subjects: Farms, Small -- South Africa -- Eastern Cape Crop yields -- South Africa -- Eastern Cape Agricultural productivity -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/11009 , vital:36450
- Description: Smallholder irrigation schemes (SIS) in South Africa have performed poorly and failed to achieve the development objectives of sustaining rural livelihoods by increasing crop production and income. Limited knowledge of crop production among farmers is one constraint to improved crop productivity and, yet little research has been carried out to relate agronomic practices to productivity. This study was aimed at identifying strategies to improve the productivity of maize-based smallholder irrigated cropping systems in South Africa, using Zanyokwe irrigation scheme (ZIS) in the Eastern Cape Province as a case study. The research design was emergent, developed progressively as influenced by the progressive analyses that were made. The research work involved two main phases: exploratory studies and refinement on-farm experiments for testing technologies as informed by the exploratory studies. Exploratory studies were aimed at describing farmer crop production practices in major crop enterprises and identifying and prioritizing major agronomic yield constraints. Findings indicated that the overall performance of the cropping systems was poor as evidenced by low overall yields of < 25% of the potential in maize and butternut. Poor management of weeds, soil fertility, plant populations and water, late planting and poor cultivar choice were the most important yield constraints. The average cropping intensity achieved by farmers was only 48%. New hybrids yielded 50 - 65% higher grain than the cultivars commonly grown by farmers. However, farmers favoured their traditional cultivars, as they preferred green maize production as opposed to dry grains. As a result of these findings, focused research was designed on options for iii improving green maize production, soil fertility, crop stand and weed management in crop production. On-farm trials were, therefore, designed to (1) compare the response to nitrogen (N) rate of direct seeded and transplanted maize; (2) evaluate comparative performance of direct seeded and transplanted green maize under farmer management, and to work out the economics of transplanting; (3) investigate the effects of row spacing and atrazine dosage on weed dynamics maize yield; (4) determine the effects of inter-row spacing and plant population on weed dynamics and maize yield; and (5) investigate the effects of pre-plant weed control, N rate and plant population on weed dynamics and butternut yield. Maize transplanting improved crop stand, had earlier maturity and yielded higher at lower N rates compared to direct seeding for both green and grain maize. Total costs that varied were higher by R3 565 ha-1 for transplanted maize compared to direct-seeded maize, but the net benefits from transplanting were also much higher by R8 773 ha-1. Farmers favoured transplanting, citing bigger cobs, early maturity and the absence of seedling damage by birds, when maize was transplanted. However, a follow-up survey conducted during the subsequent year indicated that five of the six farmers abandoned transplanting, citing shortage of labour and high cost of commercially produced seedlings. It was concluded that transplanting is unlikely to be adopted unless the labour intensiveness of manual transplanting can be solved. Increasing atrazine dosage from a third of the label recommended dosage (LRD) and reducing row spacing from 90 to 45 cm resulted in an increase in weed mortality. A 100% kill of annual broadleaf weeds was possible while iv perennial grasses and the annual broadleaf weed, Oxalis latifolia, could not be controlled even at the LRD. However, improved weed mortality with increase in atrazine dosage and/or narrow rows did not translate into improved maize productivity. In butternut, pre-plant weed control resulted in a six-fold decrease in weed biomass and a 100% increase in fruit yield. These findings demonstrated the possibility of incorporation of reduced herbicide dosages and narrow rows to achieve adequate weed control and optimise on maize yields in smallholder farming systems. The results also suggested that pre-plant weed control is one of the pre-requisite to successful butternut production in SIS in South Africa. Increasing maize population from 40 000 to 60 000 plants ha-1 resulted in a 30% grain yield increase, but decreased length of cobs. Row spacing had no effect on maize yield at 40 000 plants ha-1, but at 60 000 plants ha-1 45 cm rows resulted in 11% higher grain yield (12 547 kg ha-1) than 90 cm rows (11 288 kg ha-1). Butternut yield increased significantly (p < 0.01) with increase in plant population and N rate. The optimum butternut population and N rate were estimated at 25 000 plants ha-1 and 120 kg N ha-1, respectively. Pre-plant weed control in butternut resulted in a six-fold decrease in weed biomass. Increasing butternut planting density from 10 000 to 30 000 plants ha-1 decreased weed biomass by 47%. No marketable fruits were obtained when planting was done without prior weed control. This result suggest that application of non-selective herbicide before planting is one technique that can be used by farmers as part of integrated weed management to give the crop a competitive advantage in the early growth stages before the plants start to produce vines. Yield increased significantly (p < 0.01) with increase in plant density and N rate. The optimum plant density and N rate were estimated at 25 000 plants ha-1 and 120 kg N ha-1, respectively. These findings emphasise the need to take into consideration production practices by farmers as a basis to build up skills in the management of crop enterprises and the farm as a viable business in any efforts to improve on the performance of SIS in South Africa. Future research should concentrate on labour-saving sustainable production technologies for SIS in South Africa.
- Full Text:
Improving sanitization and fertiliser value of dairy manure and waste paper mixtures enriched with rock phosphate through combined thermophilic composting and vermicomposting
- Authors: Mupondi, Lushian Tapiwa
- Date: 2010
- Subjects: Compost , Vermicomposting , Manures , Biodegradation , Waste paper -- South Africa -- Eastern Cape , Thermophilic bacteria , Fertilizers
- Language: English
- Type: Thesis , Doctoral , PhD (Soil Science)
- Identifier: vital:11961 , http://hdl.handle.net/10353/411 , Compost , Vermicomposting , Manures , Biodegradation , Waste paper -- South Africa -- Eastern Cape , Thermophilic bacteria , Fertilizers
- Description: Thermophilic composting (TC) and vermicomposting (V) are the two most common methods used for biological stabilization of solid organic wastes. Both have their advantages and disadvantages but the proposed method of combining composting and vermicomposting (CV) borrows pertinent attributes from each of the two methods and combines them to enhance overall process and product qualities. Dairy manure and waste paper are two wastes produced in large quantities at the University of Fort Hare. The study was carried out to address the following specific objectives, to determine (i) the effectiveness of combined thermophilic composting and vermicomposting on the biodegradation and sanitization of mixtures of dairy manure and paper waste, (ii) an optimum precomposting period for dairy manure paper waste mixtures that results in vermicomposts of good nutritional quality and whose use will not jeopardize human health, (iii) the effectiveness of phosphate rock (PR) in increasing available P and degradation and nutrient content of dairy manure-paper vermicomposts, (iv) the physicochemical properties of vermicompost substituted pine bark compost and performance of resultant growing medium on plant growth and nutrient uptake. Results of this study revealed that wastes with a C: N ratio of 30 were more suitable for both V and CV as their composts were more stabilized and with higher nutrient contents than composts made from wastes with a C: N ratio of 45. Both V and CV were effective methods for the biodegradation of dairy manure and paper waste mixtures with C: N ratio of 30 but the latter was more effective in the biodegradation of waste mixtures with a C: N ratio of 45. The combinination of composting and vermicomposting eliminated the indicator pathogen E. coli 0157 from the final composts whereas V only managed to reduce the pathogen population. iv A follow up study was done to determine the effects of precomposting on pathogen numbers so as to come up with a suitable precomposting period to use when combine composting dairy manure-waste paper mixtures. Results of this study showed that over 95% of fecal coliforms, E. coli and of E. coli 0157 were eliminated from the wastes within one week of precomposting and total elimination of these and protozoan (oo)cysts achieved after 3 weeks of precomposting. The vermicomposts pathogen content was related to the waste’s precomposting period. Final vermicomposts pathogen content was reduced and varied according to precomposting period. Vermicomposts from wastes precomposted for over two weeks were less stabilized, less humified and had less nutrient contents compared to vermicomposts from wastes that were precomposted for one week or less. The findings suggest that a precomposting period of one week is ideal for the effective vermicomposting of dairy manure-waste paper mixtures. Results of the P enrichment study indicated an increase in the inorganic phosphate and a reduction in the organic phosphate fractions of dairy manure-waste paper vermicompost that were enriched with PR. This implied an increase in mineralization of organic matter and or solubilization of PR with vermicomposting time. Applying PR to dairy manure-waste paper mixtures also enhanced degradation and had increased N and P contents of dairy manure-waste paper vermicomposts. Earthworms accumulated heavy metals in their bodies and reduced heavy metal contents of vermicomposts. A study to determine the physicochemical properties of vermicompost substituted pine bark compost and performance of resultant growing medium on plant growth and nutrient uptake was done. Results obtained revealed that increasing proportions of dairy manure vermicomposts in pine bark compost improved tomato plant height, stem girth, shoot and root dry weights. v Tomatoes grew best in the 40 to 60% CV substituted pine bark and application of Horticote (7:2:1 (22)) fertilizer significantly increased plant growth in all media. Progressive substitution pine bark with dairy manure vermicomposts resulted in a decrease in the percentage total porosity, percentage air space whilst bulk density, water holding capacity, particle density, pH, electrical conductivity and N and P levels increased. Precomposting wastes not only reduced and or eliminated pathogens but also improved the stabilisation and nutrient content of dairy manure waste paper mixtures. The application of PR to dairy manure waste paper mixtures improved the chemical and physical properties of vermicomposts. Earthworms bio-accumulated the heavy metals Cd, Cr, Cu, Pb and Zn whilst the contents of these in the vermicomposts declined. It is, therefore, recommended that dairy manure waste paper mixtures be precomposted for one week for sanitization followed by PR application and vermicomposting for stabilization and improved nutrients contents of resultant vermicomposts. Substitution of pine bark compost with 40 to 60 % PR-enriched vermicompost produced a growing medium with superior physical and chemical properties which supported good seedling growth. However, for optimum seedling growth, supplementation with mineral fertilizer was found to be necessary.
- Full Text:
- Authors: Mupondi, Lushian Tapiwa
- Date: 2010
- Subjects: Compost , Vermicomposting , Manures , Biodegradation , Waste paper -- South Africa -- Eastern Cape , Thermophilic bacteria , Fertilizers
- Language: English
- Type: Thesis , Doctoral , PhD (Soil Science)
- Identifier: vital:11961 , http://hdl.handle.net/10353/411 , Compost , Vermicomposting , Manures , Biodegradation , Waste paper -- South Africa -- Eastern Cape , Thermophilic bacteria , Fertilizers
- Description: Thermophilic composting (TC) and vermicomposting (V) are the two most common methods used for biological stabilization of solid organic wastes. Both have their advantages and disadvantages but the proposed method of combining composting and vermicomposting (CV) borrows pertinent attributes from each of the two methods and combines them to enhance overall process and product qualities. Dairy manure and waste paper are two wastes produced in large quantities at the University of Fort Hare. The study was carried out to address the following specific objectives, to determine (i) the effectiveness of combined thermophilic composting and vermicomposting on the biodegradation and sanitization of mixtures of dairy manure and paper waste, (ii) an optimum precomposting period for dairy manure paper waste mixtures that results in vermicomposts of good nutritional quality and whose use will not jeopardize human health, (iii) the effectiveness of phosphate rock (PR) in increasing available P and degradation and nutrient content of dairy manure-paper vermicomposts, (iv) the physicochemical properties of vermicompost substituted pine bark compost and performance of resultant growing medium on plant growth and nutrient uptake. Results of this study revealed that wastes with a C: N ratio of 30 were more suitable for both V and CV as their composts were more stabilized and with higher nutrient contents than composts made from wastes with a C: N ratio of 45. Both V and CV were effective methods for the biodegradation of dairy manure and paper waste mixtures with C: N ratio of 30 but the latter was more effective in the biodegradation of waste mixtures with a C: N ratio of 45. The combinination of composting and vermicomposting eliminated the indicator pathogen E. coli 0157 from the final composts whereas V only managed to reduce the pathogen population. iv A follow up study was done to determine the effects of precomposting on pathogen numbers so as to come up with a suitable precomposting period to use when combine composting dairy manure-waste paper mixtures. Results of this study showed that over 95% of fecal coliforms, E. coli and of E. coli 0157 were eliminated from the wastes within one week of precomposting and total elimination of these and protozoan (oo)cysts achieved after 3 weeks of precomposting. The vermicomposts pathogen content was related to the waste’s precomposting period. Final vermicomposts pathogen content was reduced and varied according to precomposting period. Vermicomposts from wastes precomposted for over two weeks were less stabilized, less humified and had less nutrient contents compared to vermicomposts from wastes that were precomposted for one week or less. The findings suggest that a precomposting period of one week is ideal for the effective vermicomposting of dairy manure-waste paper mixtures. Results of the P enrichment study indicated an increase in the inorganic phosphate and a reduction in the organic phosphate fractions of dairy manure-waste paper vermicompost that were enriched with PR. This implied an increase in mineralization of organic matter and or solubilization of PR with vermicomposting time. Applying PR to dairy manure-waste paper mixtures also enhanced degradation and had increased N and P contents of dairy manure-waste paper vermicomposts. Earthworms accumulated heavy metals in their bodies and reduced heavy metal contents of vermicomposts. A study to determine the physicochemical properties of vermicompost substituted pine bark compost and performance of resultant growing medium on plant growth and nutrient uptake was done. Results obtained revealed that increasing proportions of dairy manure vermicomposts in pine bark compost improved tomato plant height, stem girth, shoot and root dry weights. v Tomatoes grew best in the 40 to 60% CV substituted pine bark and application of Horticote (7:2:1 (22)) fertilizer significantly increased plant growth in all media. Progressive substitution pine bark with dairy manure vermicomposts resulted in a decrease in the percentage total porosity, percentage air space whilst bulk density, water holding capacity, particle density, pH, electrical conductivity and N and P levels increased. Precomposting wastes not only reduced and or eliminated pathogens but also improved the stabilisation and nutrient content of dairy manure waste paper mixtures. The application of PR to dairy manure waste paper mixtures improved the chemical and physical properties of vermicomposts. Earthworms bio-accumulated the heavy metals Cd, Cr, Cu, Pb and Zn whilst the contents of these in the vermicomposts declined. It is, therefore, recommended that dairy manure waste paper mixtures be precomposted for one week for sanitization followed by PR application and vermicomposting for stabilization and improved nutrients contents of resultant vermicomposts. Substitution of pine bark compost with 40 to 60 % PR-enriched vermicompost produced a growing medium with superior physical and chemical properties which supported good seedling growth. However, for optimum seedling growth, supplementation with mineral fertilizer was found to be necessary.
- Full Text:
In vitro bioactivity of crude extracts of Lippia javanica on clinical isolates of Helicobacter pylori: preliminary phytochemical screening
- Authors: Nkomo, Lindelwa Precious
- Date: 2010
- Subjects: Extracts , Helicobacter pylori , Antibiotics , Drug resistance in microorganisms , Materia medica, Vegetable
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: vital:11257 , http://hdl.handle.net/10353/508 , Extracts , Helicobacter pylori , Antibiotics , Drug resistance in microorganisms , Materia medica, Vegetable
- Description: Helicobacter pylori classified as a class 1 carcinogen is a common human pathogen implicated in certain gastrointestinal diseases. Helicobacter pylori infection is acquired mainly in childhood, especially in developing countries. H. pylori infection causes peptic ulcer, duodenitis, gastritis and cancer. The growing resistance of H. pylori to antibiotics used in its treatment as well as other innate limitations of the triple therapy has necessitated a search for alternative treatment from natural sources which could be readily available, less cost effective. The antimicrobial activity of solvents (acetone, ethanol, methanol, chloroform and water) crude extracts of Lippia javanica were investigated against 31 H. pylori strains by the agar well diffusion technique. The minimum inhibitory concentration (MIC) was determined by spectrophotometric analysis at 620 nm using the broth micro dilution method and the rate of kill by broth dilution method. Phytochemical analysis was also performed. H. pylori standard strain NCTC 11638 was included as a positive control. Metronidazole and amoxicillin were used as positive control antibiotics. The ANOVA test was used to analyze the results using SPSS version 17.0. The strains were inhibited by all the extracts with inhibition zones of diameter ranging from 0-36 mm and 0-35 mm for the control antibiotic, clarithromycin. The MIC90 ranged from 0.039- 0.625 mg/mL for acetone; 0.039-1.25mg/mL for methanol, 0.00195-0.313 mg/mL for ethanol; 0.01975-2.5 mg/mL for metronidazole and 0.0048-2.5 mg/mL for amoxicillin. Acetone extract completely inhibited strain PE369C at MIC (0.1 mg/mL) and 2× MIC (0.2 mg/mL) in 18h and at ½× MIC (0.05 mg/mL) in 36h. Strain PE466C was completely inhibited at 4× MIC in 72h. Phytochemical analysis revealed the presence of flavonoids, saponins, tannins, steroids and alkaloids. The results indicate that the extracts of the leaves of L. javanica may contain compounds with anti-H. pylori activity and merits further study to identify the compounds.
- Full Text:
- Authors: Nkomo, Lindelwa Precious
- Date: 2010
- Subjects: Extracts , Helicobacter pylori , Antibiotics , Drug resistance in microorganisms , Materia medica, Vegetable
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: vital:11257 , http://hdl.handle.net/10353/508 , Extracts , Helicobacter pylori , Antibiotics , Drug resistance in microorganisms , Materia medica, Vegetable
- Description: Helicobacter pylori classified as a class 1 carcinogen is a common human pathogen implicated in certain gastrointestinal diseases. Helicobacter pylori infection is acquired mainly in childhood, especially in developing countries. H. pylori infection causes peptic ulcer, duodenitis, gastritis and cancer. The growing resistance of H. pylori to antibiotics used in its treatment as well as other innate limitations of the triple therapy has necessitated a search for alternative treatment from natural sources which could be readily available, less cost effective. The antimicrobial activity of solvents (acetone, ethanol, methanol, chloroform and water) crude extracts of Lippia javanica were investigated against 31 H. pylori strains by the agar well diffusion technique. The minimum inhibitory concentration (MIC) was determined by spectrophotometric analysis at 620 nm using the broth micro dilution method and the rate of kill by broth dilution method. Phytochemical analysis was also performed. H. pylori standard strain NCTC 11638 was included as a positive control. Metronidazole and amoxicillin were used as positive control antibiotics. The ANOVA test was used to analyze the results using SPSS version 17.0. The strains were inhibited by all the extracts with inhibition zones of diameter ranging from 0-36 mm and 0-35 mm for the control antibiotic, clarithromycin. The MIC90 ranged from 0.039- 0.625 mg/mL for acetone; 0.039-1.25mg/mL for methanol, 0.00195-0.313 mg/mL for ethanol; 0.01975-2.5 mg/mL for metronidazole and 0.0048-2.5 mg/mL for amoxicillin. Acetone extract completely inhibited strain PE369C at MIC (0.1 mg/mL) and 2× MIC (0.2 mg/mL) in 18h and at ½× MIC (0.05 mg/mL) in 36h. Strain PE466C was completely inhibited at 4× MIC in 72h. Phytochemical analysis revealed the presence of flavonoids, saponins, tannins, steroids and alkaloids. The results indicate that the extracts of the leaves of L. javanica may contain compounds with anti-H. pylori activity and merits further study to identify the compounds.
- Full Text:
Influence of mite predation on the efficacy of the gall midge Dasineura sp. as a biocontrol agent of Australian myrtle Leptospermum laevigatum (Myrtaceae) in South Africa
- Mdlangu, Thabisa Lynette Honey
- Authors: Mdlangu, Thabisa Lynette Honey
- Date: 2010
- Subjects: Dasyneura leguminicola , Myrtaceae -- South Africa , Mites as biological pest control agents , Pests -- Biological control , Biological pest control agents , Predation (Biology)
- Language: English
- Type: Thesis , Masters , MSc (Zoology)
- Identifier: vital:11789 , http://hdl.handle.net/10353/272 , Dasyneura leguminicola , Myrtaceae -- South Africa , Mites as biological pest control agents , Pests -- Biological control , Biological pest control agents , Predation (Biology)
- Description: Dasineura sp. is a gall forming midge that was introduced into South Africa for the biocontrol of the Australian myrtle, Leptospermum laevigatum. It causes galls on both the vegetative and reproductive buds of the plant. Although Dasineura sp. was initially regarded as a potentially successful agent, galling up to 99 percent of the buds of the host plant, it has been preyed on by native opportunistic mites, which caused a decline in the performance of the midge as a biocontrol agent of L. laevigatum. This raised a concern about whether this fly will be able to perform effectively in the presence of its new natural enemies. Therefore, the objectives of this study were to: 1) ascertain whether mite abundance has seasonal variations; 2) determine if plant density and plant size have an effect on midge predation by the mites; and 3) determine if midge predation varies in different locations. The study was conducted at three sites in the Hermanus area, Western Cape Province. Every three weeks for thirteen months, galls were collected and dissected so as to count and record the numbers of midge larvae, pupae, adults and mites that were found. Data collected showed that predation varied with season, and the mites were scarce during the flowering season. Predation also varied among the study sites and plant density had an effect on midge predation. Midges in smaller plants (saplings) were more vulnerable to predation than those in the bigger plants (plants from isolates and thickets). It was concluded that although mites have an effect on midge populations, they do not prevent their establishment on the plant. Therefore, a survey should be done in two to three years time to check if the midges are still persisting on the plant, vi and recommendations are that a new agent should be released to supplement the midges.
- Full Text:
- Authors: Mdlangu, Thabisa Lynette Honey
- Date: 2010
- Subjects: Dasyneura leguminicola , Myrtaceae -- South Africa , Mites as biological pest control agents , Pests -- Biological control , Biological pest control agents , Predation (Biology)
- Language: English
- Type: Thesis , Masters , MSc (Zoology)
- Identifier: vital:11789 , http://hdl.handle.net/10353/272 , Dasyneura leguminicola , Myrtaceae -- South Africa , Mites as biological pest control agents , Pests -- Biological control , Biological pest control agents , Predation (Biology)
- Description: Dasineura sp. is a gall forming midge that was introduced into South Africa for the biocontrol of the Australian myrtle, Leptospermum laevigatum. It causes galls on both the vegetative and reproductive buds of the plant. Although Dasineura sp. was initially regarded as a potentially successful agent, galling up to 99 percent of the buds of the host plant, it has been preyed on by native opportunistic mites, which caused a decline in the performance of the midge as a biocontrol agent of L. laevigatum. This raised a concern about whether this fly will be able to perform effectively in the presence of its new natural enemies. Therefore, the objectives of this study were to: 1) ascertain whether mite abundance has seasonal variations; 2) determine if plant density and plant size have an effect on midge predation by the mites; and 3) determine if midge predation varies in different locations. The study was conducted at three sites in the Hermanus area, Western Cape Province. Every three weeks for thirteen months, galls were collected and dissected so as to count and record the numbers of midge larvae, pupae, adults and mites that were found. Data collected showed that predation varied with season, and the mites were scarce during the flowering season. Predation also varied among the study sites and plant density had an effect on midge predation. Midges in smaller plants (saplings) were more vulnerable to predation than those in the bigger plants (plants from isolates and thickets). It was concluded that although mites have an effect on midge populations, they do not prevent their establishment on the plant. Therefore, a survey should be done in two to three years time to check if the midges are still persisting on the plant, vi and recommendations are that a new agent should be released to supplement the midges.
- Full Text:
Investigation and development of an e judiciary service for a citizen oriented judiciary system for rural communities
- Authors: Scott, Mfundo Shakes
- Date: 2010
- Subjects: Digital divide -- South Africa -- Eastern Cape , Rural development projects -- South Africa -- Eastern Cape , Community development -- South Africa -- Eastern Cape , User interfaces (Computer systems)
- Language: English
- Type: Thesis , Masters , MSc (Computer Science)
- Identifier: vital:11390 , http://hdl.handle.net/10353/275 , Digital divide -- South Africa -- Eastern Cape , Rural development projects -- South Africa -- Eastern Cape , Community development -- South Africa -- Eastern Cape , User interfaces (Computer systems)
- Description: One of the factors that contribute towards slow rural development is the presence of the digital divide. An area where the digital divide is still prevalent is the administration of justice within traditional contexts. One of the areas affected by this problem is the Dwesa rural community, situated on the Wild Coast of the former homeland of Transkei, in the Eastern Cape Province of South Africa. To address this problem for the Dwesa community, a research project on developing and implementing an e-Judiciary service was undertaken. The primary objective of this project was to develop a web application to support traditional justice administration in the Dwesa community. Due to the lack of a proper legal environment in this community, the e-Judiciary service acts as a portal for safe-keeping of judicial information. Such a system also serves as a platform for the administration of minor offences that are solved by the traditional courts. Furthermore, it provides a better working environment for traditional judicial leaders and eliminates the difficulty of accessing legal information by the rest of the community. Through the availability and use of the service, community members are provided with understanding and knowledge about judiciary operations and services in their community.
- Full Text:
- Authors: Scott, Mfundo Shakes
- Date: 2010
- Subjects: Digital divide -- South Africa -- Eastern Cape , Rural development projects -- South Africa -- Eastern Cape , Community development -- South Africa -- Eastern Cape , User interfaces (Computer systems)
- Language: English
- Type: Thesis , Masters , MSc (Computer Science)
- Identifier: vital:11390 , http://hdl.handle.net/10353/275 , Digital divide -- South Africa -- Eastern Cape , Rural development projects -- South Africa -- Eastern Cape , Community development -- South Africa -- Eastern Cape , User interfaces (Computer systems)
- Description: One of the factors that contribute towards slow rural development is the presence of the digital divide. An area where the digital divide is still prevalent is the administration of justice within traditional contexts. One of the areas affected by this problem is the Dwesa rural community, situated on the Wild Coast of the former homeland of Transkei, in the Eastern Cape Province of South Africa. To address this problem for the Dwesa community, a research project on developing and implementing an e-Judiciary service was undertaken. The primary objective of this project was to develop a web application to support traditional justice administration in the Dwesa community. Due to the lack of a proper legal environment in this community, the e-Judiciary service acts as a portal for safe-keeping of judicial information. Such a system also serves as a platform for the administration of minor offences that are solved by the traditional courts. Furthermore, it provides a better working environment for traditional judicial leaders and eliminates the difficulty of accessing legal information by the rest of the community. Through the availability and use of the service, community members are provided with understanding and knowledge about judiciary operations and services in their community.
- Full Text:
Land use, compensational justice and energy resource extraction in Nigeria: a socio-historical study of petroleum and coal mining communities
- Authors: Umejesi, Ikechukwu
- Date: 2010
- Subjects: Compensation (Law) -- Nigeria , Right of property -- Nigeria , Mines and mineral resources -- Nigeria , Coal mines and mining -- Nigeria
- Language: English
- Type: Thesis , Doctoral , PhD (Sociology)
- Identifier: vital:11950 , http://hdl.handle.net/10353/344 , Compensation (Law) -- Nigeria , Right of property -- Nigeria , Mines and mineral resources -- Nigeria , Coal mines and mining -- Nigeria
- Description: Scholarly and public analyses of state-community conflict in resource-rich communities, especially in Nigeria, often portray the compensational practices of the state and extractive enterprises as unjust and unsustainable. According to this view, at least three issues foreground the “unjustness”, namely: a) Inadequate compensation of land owners when land is expropriated or degraded in the process of natural resource exploration and production; b) inadequate periodic rents paid by extractive firms to land owners; and c) lack of, or inadequate socio-economic infrastructure in the host communities of extractive operations. Most analysts have therefore argued for a revamp of the compensation system and have presented the inadequacy of compensation as the underlying cause of conflict in Nigeria‟s mining communities (see Frynas, 2000b:208; Okoji, 2002:205). This thesis subjects the compensation discourse to a closer examination, especially against the backdrop of underdevelopment, pervasive poverty, environmental damage and continuing corporate-community conflict in Nigeria‟s resource-rich rural communities. The main argument is that, because of some of its underlying neoliberal assumptions, much of the compensation discourse is flawed – which is why the discourse obscures the true character of state-community and corporate-community conflict. This more so, because the discourse relies mainly on post-colonial (that is, post-1960) experiences and contemporary advocacy literature, ignores the interplay between history and contemporary developments in state-community relations, and treats compensation as an independent variable. Drawing on the concept of collective memory, and utilising historical, ethnographic and survey data from two of Nigeria‟s oldest petroleum and coal-mining communities, the thesis examines how the evolution of the Nigerian state and collective memory about aspects of that evolution have shaped state-community relations in the extractive sector. It situates state- iii community resource-related conflict within the wider socio-historical matrix of state and community contestations for ecological and natural resource sovereignty. The key finding of the thesis is that within the context of socio-ecological rights, compensation demands by local communities are textured. In the case of the communities selected for the study, such demands are often made outside, rather than within, local ethnographic ideas of “justness” and “fairness”. Hence, land-related grievances associated with natural resource extraction persist, regardless of whether or not local demands for compensation are “adequately” met by the state and extractive corporations. The thesis enriches and extends our understanding of natural resource conflict by privileging both the sociological and historical contexts of the conflict and raising questions about the dominance the state enjoys over local communities and indigenous ecological spaces.
- Full Text:
- Authors: Umejesi, Ikechukwu
- Date: 2010
- Subjects: Compensation (Law) -- Nigeria , Right of property -- Nigeria , Mines and mineral resources -- Nigeria , Coal mines and mining -- Nigeria
- Language: English
- Type: Thesis , Doctoral , PhD (Sociology)
- Identifier: vital:11950 , http://hdl.handle.net/10353/344 , Compensation (Law) -- Nigeria , Right of property -- Nigeria , Mines and mineral resources -- Nigeria , Coal mines and mining -- Nigeria
- Description: Scholarly and public analyses of state-community conflict in resource-rich communities, especially in Nigeria, often portray the compensational practices of the state and extractive enterprises as unjust and unsustainable. According to this view, at least three issues foreground the “unjustness”, namely: a) Inadequate compensation of land owners when land is expropriated or degraded in the process of natural resource exploration and production; b) inadequate periodic rents paid by extractive firms to land owners; and c) lack of, or inadequate socio-economic infrastructure in the host communities of extractive operations. Most analysts have therefore argued for a revamp of the compensation system and have presented the inadequacy of compensation as the underlying cause of conflict in Nigeria‟s mining communities (see Frynas, 2000b:208; Okoji, 2002:205). This thesis subjects the compensation discourse to a closer examination, especially against the backdrop of underdevelopment, pervasive poverty, environmental damage and continuing corporate-community conflict in Nigeria‟s resource-rich rural communities. The main argument is that, because of some of its underlying neoliberal assumptions, much of the compensation discourse is flawed – which is why the discourse obscures the true character of state-community and corporate-community conflict. This more so, because the discourse relies mainly on post-colonial (that is, post-1960) experiences and contemporary advocacy literature, ignores the interplay between history and contemporary developments in state-community relations, and treats compensation as an independent variable. Drawing on the concept of collective memory, and utilising historical, ethnographic and survey data from two of Nigeria‟s oldest petroleum and coal-mining communities, the thesis examines how the evolution of the Nigerian state and collective memory about aspects of that evolution have shaped state-community relations in the extractive sector. It situates state- iii community resource-related conflict within the wider socio-historical matrix of state and community contestations for ecological and natural resource sovereignty. The key finding of the thesis is that within the context of socio-ecological rights, compensation demands by local communities are textured. In the case of the communities selected for the study, such demands are often made outside, rather than within, local ethnographic ideas of “justness” and “fairness”. Hence, land-related grievances associated with natural resource extraction persist, regardless of whether or not local demands for compensation are “adequately” met by the state and extractive corporations. The thesis enriches and extends our understanding of natural resource conflict by privileging both the sociological and historical contexts of the conflict and raising questions about the dominance the state enjoys over local communities and indigenous ecological spaces.
- Full Text:
Local economic development: a case study of the Blue Crane Route Municipality, Eastern Cape, South Africa
- Authors: Boose, Refuoe
- Date: 2010
- Subjects: Local government -- South Africa -- Eastern Cape , Sustainable development -- South Africa -- Eastern Cape , Rural-urban relations -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD (Geography)
- Identifier: vital:11509 , http://hdl.handle.net/10353/248 , Local government -- South Africa -- Eastern Cape , Sustainable development -- South Africa -- Eastern Cape , Rural-urban relations -- South Africa -- Eastern Cape
- Description: Local economic development (LED) in the countries of the North is a voluntary activity of local government, in South Africa it is a mandatory activity. The purpose of LED is to build the capacity of a local area to improve its economic future and the quality of life for all. While local governments in South Africa are currently engaged with the concept of LED which is seen as a tool through which to achieve sustainable development, it is now recognized that there exists economic, social and environmental interdependence between rural and urban areas and a need for a balanced and mutually supportive approach to development of the rural and urban areas. Adopting the Rural-Urban, Economic and Enterprise Development (RUEED) concept, this study highlights the challenges and development problems experienced by the deep rural and urban communities in the implementation of LED activities within the Blue Crane Route Municipality (BCRM) due to the lack of social, economic and environmental sustainability and rural-urban linkages. This study located in the Blue Crane Route Municipality in the Eastern Cape, seeks to investigate and recommend a map or strategies linking together the urban communities with the poorer neighbourhoods in LED activities. The intensive research design that incorporates the case study method was used to achieve the objectives of this study. The empirical findings of the research indicate that the concept of rural-urban linkages is not an adopted strategy in implementing development programmes resulting in deep rural communities being excluded in LED activities initiated within the Blue Crane Route Municipality. The findings also reveal that the creation of employment opportunities and improvement in the standard of living are important dimensions of LED and rural-urban linkages. This study therefore recommends the adoption of a new perspective referred to as the rural-urban linkages for LED and the consideration of economic, social and environmental complementaries that exist between rural and urban areas in the Blue Crane Route Municipality. The study further indicates that it is critical that the LED policy and interventions reflect the existing patterns of interactions between the rural and urban areas of the Municipality.
- Full Text:
- Authors: Boose, Refuoe
- Date: 2010
- Subjects: Local government -- South Africa -- Eastern Cape , Sustainable development -- South Africa -- Eastern Cape , Rural-urban relations -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD (Geography)
- Identifier: vital:11509 , http://hdl.handle.net/10353/248 , Local government -- South Africa -- Eastern Cape , Sustainable development -- South Africa -- Eastern Cape , Rural-urban relations -- South Africa -- Eastern Cape
- Description: Local economic development (LED) in the countries of the North is a voluntary activity of local government, in South Africa it is a mandatory activity. The purpose of LED is to build the capacity of a local area to improve its economic future and the quality of life for all. While local governments in South Africa are currently engaged with the concept of LED which is seen as a tool through which to achieve sustainable development, it is now recognized that there exists economic, social and environmental interdependence between rural and urban areas and a need for a balanced and mutually supportive approach to development of the rural and urban areas. Adopting the Rural-Urban, Economic and Enterprise Development (RUEED) concept, this study highlights the challenges and development problems experienced by the deep rural and urban communities in the implementation of LED activities within the Blue Crane Route Municipality (BCRM) due to the lack of social, economic and environmental sustainability and rural-urban linkages. This study located in the Blue Crane Route Municipality in the Eastern Cape, seeks to investigate and recommend a map or strategies linking together the urban communities with the poorer neighbourhoods in LED activities. The intensive research design that incorporates the case study method was used to achieve the objectives of this study. The empirical findings of the research indicate that the concept of rural-urban linkages is not an adopted strategy in implementing development programmes resulting in deep rural communities being excluded in LED activities initiated within the Blue Crane Route Municipality. The findings also reveal that the creation of employment opportunities and improvement in the standard of living are important dimensions of LED and rural-urban linkages. This study therefore recommends the adoption of a new perspective referred to as the rural-urban linkages for LED and the consideration of economic, social and environmental complementaries that exist between rural and urban areas in the Blue Crane Route Municipality. The study further indicates that it is critical that the LED policy and interventions reflect the existing patterns of interactions between the rural and urban areas of the Municipality.
- Full Text:
Manure production and nutrient management in pasture-based dairy production systems
- Authors: Svinurai, Walter
- Date: 2010
- Subjects: Manures , Nitrogen -- Metabolism , Aloe -- South Africa , Pine bark , Pastures , Dairy cattle -- Nutrition , Dairy cattle -- Management , Dairy cattle -- Feeding and feeds
- Language: English
- Type: Thesis , Masters , MSc Agric (Animal Science)
- Identifier: vital:11812 , http://hdl.handle.net/10353/475 , Manures , Nitrogen -- Metabolism , Aloe -- South Africa , Pine bark , Pastures , Dairy cattle -- Nutrition , Dairy cattle -- Management , Dairy cattle -- Feeding and feeds
- Description: Manure production and nutrient management in pasture-based dairy production systems by Walter Svinurai The effect of dietary treatments on nutrient excretion was determined and an attempt to improving the retention of excreted nitrogen in stored manure using Aloe ferox leaf gel (AFLG) and pine bark was conducted at a pasture-based dairy farm. The animal mass-balance method was used to determine nutrient excretion by cows fed on three dietary treatments, Lolium perrene-based treatment (LP), Lolium multiforium-based treatment (LM) and Lolium perenne- Trifolium repens -based treatment (LTF). In separate experiments, slurry from dairy cows fed LM was amended with AFLG and pine bark at concentrations of 25, 50, 75 and 100 g/l and stored under anaerobic conditions for 16 days. The highest and lowest excretions of N, P and K were observed in LM and LP treatments, respectively. Increasing dietary N improved K and N retention in milk and, consequently increased milk urea nitrogen (MUN) and N excretion (P < 0.05). The concentrations of AFLG affected N and P retention in manure (P < 0.05). The highest retention in total Kjeldahl nitrogen (TKN) of the initial was 42% AFLG at 25g/l inclusion rate. Ammonium nitrogen (AMN) concentration increased significantly due to the interactive effect of AFLG inclusion rate and time. Pine bark powder significantly improved N and P retention in manure at all concentrations. The retention in TKN was higher (P < 0.05) at 25g/l pine bark powder than other concentrations. The interaction effect of inclusion rate and time increased iii AMN (P < 0.05). Dietary treatments significantly affected nutrient excretion, and AFLG and pine bark considerably improved N retention in stored slurry. Findings from the filed trial suggest the need for more attention on managing dietary nutrients in the post-rainy and cool-dry season when growth of pasture influenced choice of dietary treatments that led to high nutrient excretion. Field simulation of the additives to determine their efficacy and environmental hazards was recommended.
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- Authors: Svinurai, Walter
- Date: 2010
- Subjects: Manures , Nitrogen -- Metabolism , Aloe -- South Africa , Pine bark , Pastures , Dairy cattle -- Nutrition , Dairy cattle -- Management , Dairy cattle -- Feeding and feeds
- Language: English
- Type: Thesis , Masters , MSc Agric (Animal Science)
- Identifier: vital:11812 , http://hdl.handle.net/10353/475 , Manures , Nitrogen -- Metabolism , Aloe -- South Africa , Pine bark , Pastures , Dairy cattle -- Nutrition , Dairy cattle -- Management , Dairy cattle -- Feeding and feeds
- Description: Manure production and nutrient management in pasture-based dairy production systems by Walter Svinurai The effect of dietary treatments on nutrient excretion was determined and an attempt to improving the retention of excreted nitrogen in stored manure using Aloe ferox leaf gel (AFLG) and pine bark was conducted at a pasture-based dairy farm. The animal mass-balance method was used to determine nutrient excretion by cows fed on three dietary treatments, Lolium perrene-based treatment (LP), Lolium multiforium-based treatment (LM) and Lolium perenne- Trifolium repens -based treatment (LTF). In separate experiments, slurry from dairy cows fed LM was amended with AFLG and pine bark at concentrations of 25, 50, 75 and 100 g/l and stored under anaerobic conditions for 16 days. The highest and lowest excretions of N, P and K were observed in LM and LP treatments, respectively. Increasing dietary N improved K and N retention in milk and, consequently increased milk urea nitrogen (MUN) and N excretion (P < 0.05). The concentrations of AFLG affected N and P retention in manure (P < 0.05). The highest retention in total Kjeldahl nitrogen (TKN) of the initial was 42% AFLG at 25g/l inclusion rate. Ammonium nitrogen (AMN) concentration increased significantly due to the interactive effect of AFLG inclusion rate and time. Pine bark powder significantly improved N and P retention in manure at all concentrations. The retention in TKN was higher (P < 0.05) at 25g/l pine bark powder than other concentrations. The interaction effect of inclusion rate and time increased iii AMN (P < 0.05). Dietary treatments significantly affected nutrient excretion, and AFLG and pine bark considerably improved N retention in stored slurry. Findings from the filed trial suggest the need for more attention on managing dietary nutrients in the post-rainy and cool-dry season when growth of pasture influenced choice of dietary treatments that led to high nutrient excretion. Field simulation of the additives to determine their efficacy and environmental hazards was recommended.
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Maximization of power in randomized clinical trials using the minimization treatment allocation technique
- Authors: Marange, Chioneso Show
- Date: 2010
- Subjects: Clinical trials -- Statistical methods , Statistical hypothesis testing , Regression analysis , Logistic distribution , Estimation theory
- Language: English
- Type: Thesis , Masters , MSc (Biostatistics and Epidemiology)
- Identifier: vital:11777 , http://hdl.handle.net/10353/399 , Clinical trials -- Statistical methods , Statistical hypothesis testing , Regression analysis , Logistic distribution , Estimation theory
- Description: Generally the primary goal of randomized clinical trials (RCT) is to make comparisons among two or more treatments hence clinical investigators require the most appropriate treatment allocation procedure to yield reliable results regardless of whether the ultimate data suggest a clinically important difference between the treatments being studied. Although recommended by many researchers, the utilization of minimization has been seldom reported in randomized trials mainly because of the controversy surrounding the statistical efficiency in detecting treatment effect and its complexity in implementation. Methods: A SAS simulation code was designed for allocating patients into two different treatment groups. Categorical prognostic factors were used together with multi-level response variables and demonstration of how simulation of data can help to determine the power of the minimization technique was carried out using ordinal logistic regression models. Results: Several scenarios were simulated in this study. Within the selected scenarios, increasing the sample size significantly increased the power of detecting the treatment effect. This was contrary to the case when the probability of allocation was decreased. Power did not change when the probability of allocation given that the treatment groups are balanced was increased. The probability of allocation { } k P was seen to be the only one with a significant effect on treatment balance. Conclusion: Maximum power can be achieved with a sample of size 300 although a small sample of size 200 can be adequate to attain at least 80% power. In order to have maximum power, the probability of allocation should be fixed at 0.75 and set to 0.5 if the treatment groups are equally balanced.
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- Authors: Marange, Chioneso Show
- Date: 2010
- Subjects: Clinical trials -- Statistical methods , Statistical hypothesis testing , Regression analysis , Logistic distribution , Estimation theory
- Language: English
- Type: Thesis , Masters , MSc (Biostatistics and Epidemiology)
- Identifier: vital:11777 , http://hdl.handle.net/10353/399 , Clinical trials -- Statistical methods , Statistical hypothesis testing , Regression analysis , Logistic distribution , Estimation theory
- Description: Generally the primary goal of randomized clinical trials (RCT) is to make comparisons among two or more treatments hence clinical investigators require the most appropriate treatment allocation procedure to yield reliable results regardless of whether the ultimate data suggest a clinically important difference between the treatments being studied. Although recommended by many researchers, the utilization of minimization has been seldom reported in randomized trials mainly because of the controversy surrounding the statistical efficiency in detecting treatment effect and its complexity in implementation. Methods: A SAS simulation code was designed for allocating patients into two different treatment groups. Categorical prognostic factors were used together with multi-level response variables and demonstration of how simulation of data can help to determine the power of the minimization technique was carried out using ordinal logistic regression models. Results: Several scenarios were simulated in this study. Within the selected scenarios, increasing the sample size significantly increased the power of detecting the treatment effect. This was contrary to the case when the probability of allocation was decreased. Power did not change when the probability of allocation given that the treatment groups are balanced was increased. The probability of allocation { } k P was seen to be the only one with a significant effect on treatment balance. Conclusion: Maximum power can be achieved with a sample of size 300 although a small sample of size 200 can be adequate to attain at least 80% power. In order to have maximum power, the probability of allocation should be fixed at 0.75 and set to 0.5 if the treatment groups are equally balanced.
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Mobile phones interaction techniques for second economy people
- Authors: Edim, Azom Emmanuel
- Date: 2010
- Subjects: Rural development projects -- South Africa -- Eastern Cape , Poverty -- South Africa -- Eastern Cape , Cell phone systems -- South Africa -- Eastern Cape , User interfaces (Computer systems) , Human-computer interaction , Community development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD (Computer Science)
- Identifier: vital:11392 , http://hdl.handle.net/10353/519 , Rural development projects -- South Africa -- Eastern Cape , Poverty -- South Africa -- Eastern Cape , Cell phone systems -- South Africa -- Eastern Cape , User interfaces (Computer systems) , Human-computer interaction , Community development -- South Africa -- Eastern Cape
- Description: Second economy people in developing countries are people living in communities that are underserved in terms of basic amenities and social services. Due to literacy challenges and user accessibility problems in rural communities, it is often difficult to design user interfaces that conform to the capabilities and cultural experiences of low-literacy rural community users. Rural community users are technologically illiterate and lack the knowledge of the potential of information and communication technologies. In order to embrace new technology, users will need to perceive the user interface and application as useful and easy to interact with. This requires proper understanding of the users and their socio-cultural environment. This will enable the interfaces and interactions to conform to their behaviours, motivations as well as cultural experiences and preferences and thus enhance usability and user experience. Mobile phones have the potential to increase access to information and provide a platform for economic development in rural communities. Rural communities have economic potential in terms of agriculture and micro-enterprises. Information technology can be used to enhance socio-economic activities and improve rural livelihood. We conducted a study to design user interfaces for a mobile commerce application for micro-entrepreneurs in a rural community in South Africa. The aim of the study was to design mobile interfaces and interaction techniques that are easy to use and meet the cultural preferences and experiences of users who have little to no previous experience of mobile commerce technology. And also to explore the potentials of information technologies rural community users, and bring mobile added value services to rural micro-entrepreneurs. We applied a user-centred design approach in Dwesa community and used qualitative and quantitative research methods to collect data for the design of the user interfaces (graphic user interface and voice user interface) and mobile commerce application. We identified and used several interface elements to design and finally evaluate the graphical user interface. The statistics analysis of the evaluation results show that the users in the community have positive perception of the usefulness of the application, the ease of use and intention to use the application. Community users with no prior experience with this technology were able to learn and understand the interface, recorded minimum errors and a high level of v precision during task performance when they interacted with the shop-owner graphic user interface. The voice user interface designed in this study consists of two flavours (dual tone multi-frequency input and voice input) for rural users. The evaluation results show that community users recorded higher tasks successes and minimum errors with the dual tone multi-frequency input interface than the voice only input interface. Also, a higher percentage of users prefer the dual tone multi-frequency input interface. The t-Test statistical analysis performed on the tasks completion times and error rate show that there was significant statistical difference between the dual tone multi-frequency input interface and the voice input interface. The interfaces were easy to learn, understand and use. Properly designed user interfaces that meet the experience and capabilities of low-literacy users in rural areas will improve usability and users‟ experiences. Adaptation of interfaces to users‟ culture and preferences will enhance information services accessibility among different user groups in different regions. This will promote technology acceptance in rural communities for socio-economic benefits. The user interfaces presented in this study can be adapted to different cultures to provide similar services for marginalised communities in developing countries
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- Authors: Edim, Azom Emmanuel
- Date: 2010
- Subjects: Rural development projects -- South Africa -- Eastern Cape , Poverty -- South Africa -- Eastern Cape , Cell phone systems -- South Africa -- Eastern Cape , User interfaces (Computer systems) , Human-computer interaction , Community development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD (Computer Science)
- Identifier: vital:11392 , http://hdl.handle.net/10353/519 , Rural development projects -- South Africa -- Eastern Cape , Poverty -- South Africa -- Eastern Cape , Cell phone systems -- South Africa -- Eastern Cape , User interfaces (Computer systems) , Human-computer interaction , Community development -- South Africa -- Eastern Cape
- Description: Second economy people in developing countries are people living in communities that are underserved in terms of basic amenities and social services. Due to literacy challenges and user accessibility problems in rural communities, it is often difficult to design user interfaces that conform to the capabilities and cultural experiences of low-literacy rural community users. Rural community users are technologically illiterate and lack the knowledge of the potential of information and communication technologies. In order to embrace new technology, users will need to perceive the user interface and application as useful and easy to interact with. This requires proper understanding of the users and their socio-cultural environment. This will enable the interfaces and interactions to conform to their behaviours, motivations as well as cultural experiences and preferences and thus enhance usability and user experience. Mobile phones have the potential to increase access to information and provide a platform for economic development in rural communities. Rural communities have economic potential in terms of agriculture and micro-enterprises. Information technology can be used to enhance socio-economic activities and improve rural livelihood. We conducted a study to design user interfaces for a mobile commerce application for micro-entrepreneurs in a rural community in South Africa. The aim of the study was to design mobile interfaces and interaction techniques that are easy to use and meet the cultural preferences and experiences of users who have little to no previous experience of mobile commerce technology. And also to explore the potentials of information technologies rural community users, and bring mobile added value services to rural micro-entrepreneurs. We applied a user-centred design approach in Dwesa community and used qualitative and quantitative research methods to collect data for the design of the user interfaces (graphic user interface and voice user interface) and mobile commerce application. We identified and used several interface elements to design and finally evaluate the graphical user interface. The statistics analysis of the evaluation results show that the users in the community have positive perception of the usefulness of the application, the ease of use and intention to use the application. Community users with no prior experience with this technology were able to learn and understand the interface, recorded minimum errors and a high level of v precision during task performance when they interacted with the shop-owner graphic user interface. The voice user interface designed in this study consists of two flavours (dual tone multi-frequency input and voice input) for rural users. The evaluation results show that community users recorded higher tasks successes and minimum errors with the dual tone multi-frequency input interface than the voice only input interface. Also, a higher percentage of users prefer the dual tone multi-frequency input interface. The t-Test statistical analysis performed on the tasks completion times and error rate show that there was significant statistical difference between the dual tone multi-frequency input interface and the voice input interface. The interfaces were easy to learn, understand and use. Properly designed user interfaces that meet the experience and capabilities of low-literacy users in rural areas will improve usability and users‟ experiences. Adaptation of interfaces to users‟ culture and preferences will enhance information services accessibility among different user groups in different regions. This will promote technology acceptance in rural communities for socio-economic benefits. The user interfaces presented in this study can be adapted to different cultures to provide similar services for marginalised communities in developing countries
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Narrative play therapy and the journey of a boy diagnosed with a learning disability: a case study
- Authors: Topper, Kegan
- Date: 2010
- Subjects: Play therapy -- Case studies , Narrative therapy -- Case studies , Children with disabilities , Learning disabilities , Cognitive therapy for children , Play -- Psychological aspects
- Language: English
- Type: Thesis , Masters , M Soc Sc (C Psy)
- Identifier: vital:11854 , http://hdl.handle.net/10353/313 , Play therapy -- Case studies , Narrative therapy -- Case studies , Children with disabilities , Learning disabilities , Cognitive therapy for children , Play -- Psychological aspects
- Description: This study offers a detailed exploration of the personal narrative of a nine year old boy diagnosed with a learning disability, and explains how the nature of the therapeutic relationship facilitated shifts in his personal understandings of himself, others and the world. Children diagnosed with learning disabilities experience a range of challenges in their different life contexts, and particularly within the school context. This is often because of constant evaluation and surveillance from teachers, family members and peers, who define the child within rigid and limiting frameworks. Soon enough children diagnosed with learning disabilities develop problem-saturated narratives that can significantly influence their relationship with themselves and others. This is because the individualising effects of having a disability cause them to feel different or isolated from their peers. This study illustrates an eight session case study, facilitated by a narrative play therapy approach, between a counsellor, a child and his parents. The therapeutic encounters were intended to assist the child in moving away from problem-saturated narratives of incompetence and inferiority towards more preferred narratives that would positively influence his self esteem. Key words: learning disability, dyslexia, narrative, narrative therapy, identity, self esteem. Children Diagnosed with a Learning Disability Children who have been diagnosed with a learning disability often experience themselves and their world very differently from other children (Rodis, Garrod, & Boscardin, 2001). Within the educational system a considerable amount of pressure is placed on children to succeed. The educational discourse of achievement that professes itself to be the only direction from which a successful future can be attained, marginalizes and rejects those children whose knowledge and skills exist outside this rigid and oftentimes insensitive system of evaluation. As a result, children soon create problem saturated narratives, believing themselves to be the problem. However, in the last two decades there has been a move from reductionism to constructivism and as a result research in the field of learning disabilities has started to focus on children’s non-traditional strengths and talents, which are often misunderstood and ignored by schools. Armstrong (1987) sums it up as follows: The schools allow millions of imaginative kids to go unrecognised
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- Authors: Topper, Kegan
- Date: 2010
- Subjects: Play therapy -- Case studies , Narrative therapy -- Case studies , Children with disabilities , Learning disabilities , Cognitive therapy for children , Play -- Psychological aspects
- Language: English
- Type: Thesis , Masters , M Soc Sc (C Psy)
- Identifier: vital:11854 , http://hdl.handle.net/10353/313 , Play therapy -- Case studies , Narrative therapy -- Case studies , Children with disabilities , Learning disabilities , Cognitive therapy for children , Play -- Psychological aspects
- Description: This study offers a detailed exploration of the personal narrative of a nine year old boy diagnosed with a learning disability, and explains how the nature of the therapeutic relationship facilitated shifts in his personal understandings of himself, others and the world. Children diagnosed with learning disabilities experience a range of challenges in their different life contexts, and particularly within the school context. This is often because of constant evaluation and surveillance from teachers, family members and peers, who define the child within rigid and limiting frameworks. Soon enough children diagnosed with learning disabilities develop problem-saturated narratives that can significantly influence their relationship with themselves and others. This is because the individualising effects of having a disability cause them to feel different or isolated from their peers. This study illustrates an eight session case study, facilitated by a narrative play therapy approach, between a counsellor, a child and his parents. The therapeutic encounters were intended to assist the child in moving away from problem-saturated narratives of incompetence and inferiority towards more preferred narratives that would positively influence his self esteem. Key words: learning disability, dyslexia, narrative, narrative therapy, identity, self esteem. Children Diagnosed with a Learning Disability Children who have been diagnosed with a learning disability often experience themselves and their world very differently from other children (Rodis, Garrod, & Boscardin, 2001). Within the educational system a considerable amount of pressure is placed on children to succeed. The educational discourse of achievement that professes itself to be the only direction from which a successful future can be attained, marginalizes and rejects those children whose knowledge and skills exist outside this rigid and oftentimes insensitive system of evaluation. As a result, children soon create problem saturated narratives, believing themselves to be the problem. However, in the last two decades there has been a move from reductionism to constructivism and as a result research in the field of learning disabilities has started to focus on children’s non-traditional strengths and talents, which are often misunderstood and ignored by schools. Armstrong (1987) sums it up as follows: The schools allow millions of imaginative kids to go unrecognised
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