Evaluation and management of cover crop species and their effects on weed dynamics, soil fertility and maize (Zea mays L.) productivity under irrigation in the Eastern Cape Province, South Africa
- Authors: Murungu, Farayi Solomon
- Date: 2010
- Subjects: Crops -- South Africa , Conservation of natural resources -- South Africa -- Eastern Cape , Agriculture -- South Africa -- Eastern Cape , Soil percolation -- South Africa -- Eastern Cape , Soil permeability -- South Africa -- Eastern Cape , Irrigation farming -- South Africa -- Eastern Cape , Corn -- South Africa -- Eastern Cape , Soil fertility -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD (Crop Science)
- Identifier: vital:11866 , http://hdl.handle.net/10353/335 , Crops -- South Africa , Conservation of natural resources -- South Africa -- Eastern Cape , Agriculture -- South Africa -- Eastern Cape , Soil percolation -- South Africa -- Eastern Cape , Soil permeability -- South Africa -- Eastern Cape , Irrigation farming -- South Africa -- Eastern Cape , Corn -- South Africa -- Eastern Cape , Soil fertility -- South Africa -- Eastern Cape
- Description: The current interest in conservation agriculture (CA) technologies is a result of the need to reduce excessive land degradation in most crop producing areas as well as to enhance sustainable food production. Cover crops that are usually grown under CA to provide soil cover, may offer secondary benefits, depending on the farming system. The concept of growing cover crops is a relatively new phenomenon to smallholder farmers. Production of large biomass yields and weed suppression from cover crops were major challenges affecting success and uptake of CA technologies by smallholder irrigation farmers. Coupled with this, low soil fertility limit maize productivity and reduce water use efficiency on smallholder irrigation schemes in what is largely a water strained agro-ecology in South Africa. While cover cropping can increase maize productivity, benefits of different types of mulch are not well understood, leading to challenges in selecting the most appropriate cover crop species to grow in the Eastern Cape Province (EC) of South Africa (SA) which has a warm temperate climate. With respect to any new technology, smallholder farmers are more interested in the economic benefits. Cover crops have been defined as leguminous or non-leguminous plants used for ground cover in various temporal and special configurations used in crop or animal production systems. The purpose of these cover crops is to improve on or more of the following: soil erosion, availability and cycling of N, P, K, Ca and other nutrients, soil moisture and water infiltration, and weed or pest control (Eilitta et al., 2004).. Improvement of animal or human diet may be additional goals. This definition accommodates diverse systems which may include intercrop and sole-cropping systems. In the Eastern Cape Province of South Africa, a government initiative has promoted the growing of winter cover crops in smallholder irrigation schemes (Allwood, 2006). In other parts of Africa, legume food crops have been simultaneously grown with cereal staples to improve both soil cover and human diet (Eilitta et al., 2004). Winter experiments were undertaken in 2007 and 2008 to evaluate biomass accumulation, C and N uptake, weed suppression and response to fertilization. Winter cover crops planted included; oats (Avena sativa), grazing vetch (Vicia dasycarpa), faba bean (Vicia faba), forage peas (Pisum sativum) and lupin (Lupinus angustifolius). After cover crops were terminated, the effects of residues on weeds, fertility, moisture conservation and maize productivity were undertaken in the 2007/08 and 2008/09 summer seasons. Field studies were also done in the 2007/08 and 2008/09 summer seasons to investigate effects of strip intercropping patterns (3:2; 4:2; and 6:2 patterns) of maize (cv. PAN 6479) with mucuna (Mucuna pruriens) or sunnhemp (Crotalaria juncea) on maize productivity and summer cover crop biomass production. In a separate experiment effects of relay intercropping sunnhemp, mucuna and sorghum (Sorghum bicolor) on biomass accumulation and maize productivity were investigated. Decomposition, N and P release from both winter cover crops and summer cover crops were also assessed in laboratory incubation experiments. Oats, grazing vetch and forage peas cover crops produced mean dry mass of 13873 kg/ha, 8945.5 kg/ha and 11073 kg/ha, respectively, while lupin had the lowest dry mass of 1226 kg/ha over the two seasons. Oats responded to fertilization while, there was little or no response from the other winter cover crops. Oats and grazing vetch also reduced weed density by 90 % and 80 % respectively while lupin only reduced weed density by 23 % in relation to the control plots. Nitrogen uptake was 254 kg N/ha for oats while it was 346 kg N /ha for grazing vetch. In the subsequent summer season, grazing vetch and forage pea residues significantly (P < 0.01) improved soil inorganic N. Oat and grazing vetch residues significantly (P < 0.05) reduced weed dry masss and weed species diversity compared to plots with lupin residues and the control. Lack of maize fertilization tended to reduce maize yields but not for maize grown on grazing vetch residues. From an economic perspective, grazing vetch resulted in the highest returns. Decomposition of winter cover crops was much faster for grazing vetch followed by forage peas and lastly oats. Oats had 40 % ash free dry mass remaining after 124 days while grazing vetch and forage peas had 7 % and 16 % respectively. Maximum net mineralized N and P were greater for grazing vetch (84.8 mg N/kg; 3.6 mg P/kg) compared to forage peas (66.3 mg N/kg; 2.7 mg P/ha) and oats (13.7 mg N/kg; 2.8 mg P/kg). In the strip intercropping trials, sunnhemp achieved the highest biomass yield of 4576 kg/ha in the 3:2 pattern while mucuna achieved 1897 kg/ha for the same strip pattern. The 3:2 strip intercropping pattern slightly depressed yields, however, yield reduction was more pronounced in the first season where water stress was experienced. Growing maize on previous cover crop strips failed to increase maize productivity probably due to weed growth during the fallow reducing mineral N in these strips. Decomposition was faster in sunnhemp leaves and mucuna compared to sunnhemp stems. Sunnhemp stems had about 65 % of ash free dry mass remaining after the end of the experiment at 132 days while just over 10 % of mucuna and sunnhemp leaves still remained. Mucuna mineralized 60 mg N/kg and 3.2 mg P/kg and sunnhemp mineralized 45 mg N/kg and 3.5 mg P/kg. Relay intercropping did not significantly (P > 0.05) affect maize biomass and grain yield. Sorghum experienced the largest drop in biomass when relay-intercropped with maize. Mucuna resulted in the highest N uptake (271 kg N/ha) in sole cropping while sorghum had the lowest (88 kg N/ha). Grazing vetch results in high biomass yields with minimal fertilizer application in a warm-temperate climate. Grazing vetch mulch is also the most cost effective mulch for better early weed control, improving soil mineral N status, water conservation and ultimately enhanced maize productivity in smallholder irrigation maize-based systems. The 3:2 pattern maximizes summer cover crop biomass yields compared to the 6:2 and 4:2 patterns. However, the 3:2 pattern may slightly depress yields in a water stressed environment. Relay intercropping mucuna, sunnhemp and sorghum into a maize crop at 42 days after maize sowing has no effect on maize productivity while cover crop biomass yields are low. Having a long winter fallow period after maize harvesting, a common practice in the study area, reduces the positive impact of legume cover crops on soil mineral N. Results suggest that winter cover crops may result in weed control, soil fertility and maize yield improvement benefits while a long fallow period may cancel-out these benefits for summer cover crops. Grazing vetch is a cost effective cover crop that produces high maize yields with minimal fertilizer input. Maize growing on oat mulch requires more fertilizer application than crops growing on grazing vetch mulch. Conservation agriculture systems in which summer cover crops are grown alongside the maize crop with a long winter fallow period do not produce the intended CA benefits.
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- Date Issued: 2010
Evaluation and mapping of the spatial variability of soil fertility at Zanyokwe Irrigation Scheme in the Eastern Cape, South Africa
- Authors: Manyevere, Alen
- Date: 2010
- Subjects: Soil surveys -- South Africa -- Eastern Cape , Irrigation farming -- South Africa , Soil fertility -- South Africa -- Eastern Cape , Soils -- Analysis , Soils -- Testing , Crop yields , Soils Classification
- Language: English
- Type: Thesis , Masters , MSc Agric (Soil Science)
- Identifier: vital:11176 , http://hdl.handle.net/10353/d1001019 , Soil surveys -- South Africa -- Eastern Cape , Irrigation farming -- South Africa , Soil fertility -- South Africa -- Eastern Cape , Soils -- Analysis , Soils -- Testing , Crop yields , Soils Classification
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- Date Issued: 2010
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.
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- Date Issued: 2010
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.
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- Date Issued: 2010
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
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- Date Issued: 2010
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
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- Date Issued: 2010
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
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- Date Issued: 2010
Impact of in-field rainwater harvesting technology on household food security: a case of Guquka and Khayalethu villages in Central Eastern Cape Province
- 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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- Date Issued: 2010
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.
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- Date Issued: 2010
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.
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- Date Issued: 2010
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
- 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.
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- Date Issued: 2010
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.
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- Date Issued: 2010
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.
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- Date Issued: 2010
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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- Date Issued: 2010
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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- Date Issued: 2010
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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- Date Issued: 2010
Neotectonics and its applications for the exploration of groundwater in the fractured Karoo aquifers in the Eastern Cape,South Africa
- Authors: Madi, Kakaba
- Date: 2010
- Subjects: Water well drilling -- South Africa -- Eastern Cape , Aquifers -- South Africa -- Eastern Cape , Water -- supply engineering -- South Africa -- Eastern Cape , Prospecting -- Geophysical methods , Groundwater -- Research -- Methodology
- Language: English
- Type: Thesis , Masters , MSc (Geology)
- Identifier: vital:11523 , http://hdl.handle.net/10353/362 , Water well drilling -- South Africa -- Eastern Cape , Aquifers -- South Africa -- Eastern Cape , Water -- supply engineering -- South Africa -- Eastern Cape , Prospecting -- Geophysical methods , Groundwater -- Research -- Methodology
- Description: This study is part of an NRF sponsored research project entitled “Neotectonics and its applications for the exploration of groundwater in the fractured Karoo aquifers in the Eastern Cape” under the NRF Niche area of Water Resources Management and Sustainable Development in the Eastern Cape Province. The identification of relatively highly productive wells in the Karoo fractured aquifers is extremely difficult. This study aims to identify neotectonic zones and lower stress fields, and apply the results to groundwater exploration in the Eastern Cape Province. The methodologies adopted in this study include: a comprehensive literature review, extensive field mapping and investigation such as road cuts, sampling for laboratory studies, examination of seismic data, study of hot and ordinary springs, and interpretation of aerial photography and satellite images. Three main neotectonic belts were identified in the Eastern Cape (southern neotectonic belt, northern neotectonic belt and eastern neotectonic belt) based on literature review and field interpretations. The southern neotectonic belt (from the Cape Fold Belt to the lower Beaufort Group boundary) is characterized by the reactivation of the Coega-Bavianskloof and Sauer faults, the presence of a hot spring near Fort Beaufort, the slickenlines and discrete slickenlines and specifically the seismic events that were recorded in the Eastern Cape from 1850 to 2007. In this southern neotectonic belt the remote sensing has also revealed the presence of the Fort Beaufort fracture, the quartz veins seen in some dolerites and the different vegetation types along it may indicate that this fracture is possibly a fault; moreover the Quaternary sediments and weathered dolerites indicate that the Fort iii Beaufort fracture is characterized by groundwater circulation and accordingly is a good target for groundwater exploration, this fracture is a post-Karoo structure and possibly a neotectonic feature. In addition, the kaolin deposit, chiefly developed in the Dwyka tillite near Grahamstown is clearly controlled by neotectonic fracture zones. The northern neotectonic belt near the country of Lesotho is marked by the presence of the Senqu seismotectonic regime and hot springs. The Quaternary Amatole-Swaziland (formerly Ciskei-Swaziland) axis of uplift makes the eastern part of the province the third neotectonic zone, the asymmetric meanders of the Mbashe river in the vicinity of Qunu near Mthatha derived possibly from this Quaternary uplift; this asymmetric feature of meanders implies that the river has tried to maintain stability of its valley where tilting occurred. Within these neotectonic belts the central part of the Eastern Cape may be considered a static and inactive belt. A northwesterly trend for the maximum principal compresssional stress predominates in the Eastern Cape and is correlated with the present major structural control of the province. The current stress regime determination was derived from faults, joints and quartz veins only on kaolin deposits. Systematic joints reflect regional tectonic stress trajectories at the time of fracturing. Discharge rates of groundwater from boreholes as provided by the Department of Water and Forestry were used to confirm and predict water exploration targets. The region of Tabankulu (near Kwazulu Natal) in the northern neotectonic belt has remarkable discharge rates of groundwater (11.1 l/s, 4.65 l/s, 6.49 l/s, 42 l/s). The region of Mthatha, nearly surrounding the Amatole-Swaziland axis (former Ciskei-Swaziland iv axis) of uplift which might have generated some new faults, has a number of springs. These two regions should serve as case studies for future research. Apart from these two regions, two others regions can be considered as case studies for future groundwater exploration targets: the Bath Farm hot spring near the Fort Beaufort neotectonic fault and the vicinity of what is known as the Fort Beaufort fracture near Teba and Cimezile villages 20km north west of Fort Beaufort. It is concluded that the study of neotectonics and stress fields may be a useful tool for groundwater exploration in the Karoo fractured aquifers in the Eastern Cape, and in similar regions elsewhere in South Africa and in Africa.
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- Date Issued: 2010
Population biology and aspects of the socio-spatial organisation of the woodland dormouse Graphiurus Murinus (Desmaret, 1822) in the Great Fish River Reserve, South Africa
- Authors: Madikiza, Zimkitha Josephine Kimberly
- Date: 2010
- Subjects: Dormice , Mice , Muridae , Spatial behavior , Territoriality (Zoology) , Crowding stress
- Language: English
- Type: Thesis , Masters , MSc (Zoology)
- Identifier: vital:11788 , http://hdl.handle.net/10353/443 , Dormice , Mice , Muridae , Spatial behavior , Territoriality (Zoology) , Crowding stress
- Description: The population biology and socio-spatial organisation of the woodland dormouse, Graphiurus murinus (Desmarest, 1822), was investigated in a riverine forest at the Great Fish River Reserve (GFRR), South Africa. Data were collected by means of a monthly live trapping and nestbox monitoring programme. Between February 2006 and June 2007, 75 woodland dormice were trapped and/or found in nestboxes and marked: these were 39 adults (13 males, 21 females, five undetermined) and 36 juveniles (five males, 14 females, 17 undetermined). The population showed a steady increase from June 2006–November 2006 and a peak in December 2006–January 2007 as a result of the influx of juveniles. The minimum number of dormice known to be alive (MNA) varied between 40 in December 2006– January 2007 (summer), and a low of three in June 2007 (winter). The range in population density was therefore between 1.2 and 16 dormice per ha. Winter mortality and/or spring dispersal accounted for the disappearance of 55 percent of juveniles. The overall annual adult:juvenile ratio was 1.08. The overall sex ratio was 1.94 female per one male. In females, reproductive activity was observed from September 2006 to end January 2007. The pattern observed in males was similar, as dormice with descended testes were exclusively found from October to end January. Females gave birth during the second half of October to beginning of February. Litters (n = 11) consisted of an average (± SD) 3.73 ± 0.47 young. Over the study period, 27 dormice were trapped or found in nestboxes more than eight times, thus allowing me to estimate their home range size and the spatial overlap between these individuals. On average, dormouse home range size was 2,514 m2 (range: 319 – 4,863 m2). No difference was recorded between one-year old adults and older adults, or between all adults and juveniles. However, adult male dormice (3,989 m2, n = 5) had home ranges almost twice as large as females (2,091 m2, n = 9). No similar trend was found in juveniles. Intrasexual home range overlap was on average 62 percent in adult males, and 26 percent in adult females. However, females overlapped with more neighbouring female home ranges than did males with neighbouring male home ranges, so that, as for males, only small parts of female home ranges were really exclusive. On average, males overlapped a larger Abstract Ecology of woodland dormice M.Sc. Thesis 16 proportion (48 percent) of female home ranges than did females with neighbouring male home ranges (27 percent). In addition, males overlapped with significantly more female home ranges (7.8) than did females with male home ranges (4.9). Trapping success and nestbox data agree with the socio-ecological model. Females showed increased mobility during summer, more likely to find suitable nesting sites, and food for milk production during the reproductive season. The use of nestboxes, however, was constant throughout the year. In males, both the trapping success and nestbox use were higher during the mating season (spring), when an increased mobility and occupation of nestboxes probably increased the chances to locate and mate with (a) receptive female(s). Hence, food and (artificial) nest sites may constitute an important resource for females, whereas females seem to represent the main resource for males. Although food availability was not determined, a comparison of female and male distribution patterns provided interesting information on the mating system of woodland dormice. In GFRR, the dispersion pattern of female woodland dormice was “rather” clumped, i.e. females were non-territorial. As some females showed a dyadic intrasexual overlap of up to 90 percent, and population density was very high at the study site, this may indicate that food was very abundant and/or renewed rapidly. Based on the wide range of birth dates observed during the study period, females clearly come into oestrus at different times. In such circumstances (asynchronous sexual receptivity in females), the Female in Space and Time Hypothesis (Ims 1987a) predicts that males will be non-territorial and promiscuous. Live-trapping, nestbox use and home range data indeed suggested that male woodland dormice do not defend territories, but search for and aggregate around receptive females during the mating season.
- Full Text:
- Date Issued: 2010
Prevalence and risk factors for Helicobacter pylori transmission in the Eastern Cape Province application of immunological molecular and demographic methods
- Authors: Dube, Callote
- Date: 2010
- Subjects: Helicobacter pylori , Bacterial diseases , Gastritis -- Risk factors , Bacterial diseases -- Risk factors , Gram-negative bacteria , Gram-negative bacterial infections , Helicobacter , Helicobacter infections , Helicobacter pylori -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: vital:11262 , http://hdl.handle.net/10353/265 , Helicobacter pylori , Bacterial diseases , Gastritis -- Risk factors , Bacterial diseases -- Risk factors , Gram-negative bacteria , Gram-negative bacterial infections , Helicobacter , Helicobacter infections , Helicobacter pylori -- South Africa -- Eastern Cape
- Description: Helicobacter pylori (H. pylori) is a microaerophilic, Gram-negative motile curved rod that inhabits the gastric mucosa of the human stomach. The organism chronically infects billions of people worldwide and is one of the most genetically diverse of bacterial species. Infection with the organism potentially induces chronic gastritis and peptic ulcer disease. In addition, H. pylori plays a role in the etiology of gastric cancer and gastric MALT lymphoma. The risk of infection is increased in those living in the developing world, which has been ascribed to precarious hygiene standards, crowded households, and deficient sanitation common in this part of the world. Thus, the aim of this study was to identify the risk factors in the transmission of H. pylori in our environment, i.e. in Nkonkobe Municipality in the Eastern Cape Province, South Africa. Faecal samples were collected from 356 apparently healthy subjects, consisting of 168 males and 188 females aged from 3 months to 60 years (Mean = 31 years). A standardized questionnaire was applied, it described demographic characteristics including age, sex, household hygiene, socioeconomic status, area of residence, duration of stay in the area, sharing bath water, sharing tooth brush, habit of sucking thumb, medication currently being taken or medication taken within the past three months, source of water, type of toilet used, education and occupation. A sandwich-type enzyme immunoassay amplification technology (Amplified IDEIA TM Hp StAR TM , Oxoid, UK) was used to analyze the faecal samples for the detection of H. pylori antigens using monoclonal antibodies specific for H. pylori antigens. To assess the possibility of faecal oral route with tap water as an intermediary link, PCR targeting the ureC (glmM), a highly conserved gene in H. pylori ii was carried out to detect H. pylori DNA in faecal samples of already positive samples by HpSA test as well as in direct tap water used by the H. pylori positive subjects. QIAamp DNA stool mini kit was used to extract DNA from faecal samples. Tap water samples were then obtained using sterile bottles from areas inhabited by H. pylori positive subjects as determined by HpSA test and PCR. DNA extraction from water samples was done using UltraCleanTM Water DNA Isolation Kit (0.22μm) according to the manufacturer’s instructions. PCR with primers specific for H. pylori glmM gene was carried out with both positive and negative controls incorporated. Fisher’s exact test was used to assess the univariate association between H. pylori infection and the possible risk factors. Odds ratio (OR) and the corresponding 95 percent confidence interval (CI) were calculated to measure the strength of association using EPI INFO 3.41 package. P values of < .05 were required for significance. The precision rate of the diagnostic tests used was also determined. H. pylori antigen was detected in 316 of the 356 subjects giving an overall prevalence of 88.8 percent. Prevalence increased with age from 75.9 percent in children < 12 years age to 100 percent in the age group from 13 years to 24 years, also 100 percent prevalence of H. pylori was recorded in young adults aged 25-47 years and subjects aged 60 years (P < .05). H. pylori prevalence was higher in females than in males. Of 188 females who participated in the study, H. pylori antigen was detected in 172 (91.5 percent) versus 144 (85.7 percent) of 168 males (P > .05). Interestingly, H pylori antigen was detected more often (100 percent) in the high socioeconomic group than in those of low socioeconomic group (85.9 percent). Sixteen (66.7 percent) of twenty four faecal samples that had previously tested positive for the organism by HpSA test were confirmed positive by PCR. However none of the treated tap water samples tested positive for the organism by PCR. The present iii study revealed a high prevalence of H. pylori in faecal samples of asymptomatic individuals in the Nkonkobe Municipality, an indication of active infection. The obtained results also revealed that direct treated tap water might not be playing a crucial role in the oral transmission of H. pylori in the studied population.
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- Date Issued: 2010
Prevalence of listeria pathogens in effluents of some wastewater treatment facilities in the Eastern Cape province of South Africa
- Authors: Odjadjare, Emmanuel Erufuare Onogwuwhenya
- Date: 2010
- Subjects: Listeria -- South Africa -- Eastern Cape , Sewage -- Purification -- South Africa -- Eastern Cape , Effluent quality -- South Africa -- Eastern Cape , Water -- Pollution -- South Africa -- Eastern Cape , Water -- Purification -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD (Microbiology)
- Identifier: vital:11264 , http://hdl.handle.net/10353/246 , Listeria -- South Africa -- Eastern Cape , Sewage -- Purification -- South Africa -- Eastern Cape , Effluent quality -- South Africa -- Eastern Cape , Water -- Pollution -- South Africa -- Eastern Cape , Water -- Purification -- South Africa -- Eastern Cape
- Description: Wastewater discharges may contain health compromising pathogens and carcinogenic and/or chemical substances that could compromise the public health and impact negatively on the environment. The present study was conducted between August 2007 and July 2008 to evaluate the Listeria abundance (as free-living and plankton associated species) and physicochemical qualities of the final effluents of three wastewater treatment facilities in the Eastern Cape Province of South Africa selected to represent typical urban, peri-urban and rural communities and the impact of the discharged final effluents on their respective receiving watershed, as well as to elucidated the in vitro antibiotic susceptibilities and resistance genes profile of Listeria species isolated from the final effluents. The suitability of the secondary effluent of the urban treatment facility (as a case study) for use in agriculture and aquaculture with reference to recommended standards was also determined. Wastewater samples were collected from the raw sewage, secondary effluent, final treated effluent, discharge point, 500 m upstream discharge point, and 500 m downstream discharge point from all three locations on a monthly basis throughout the study period. Listeria abundance in the final effluents and the receiving watersheds varied between 2.9× 100 and 3.52 × 105cfu/ml across the sampled locations. Free-living listerial density across the sampled locations ranged between 0 and 3.2 × 103cfu/ml while counts of Listeria species attached to large (180 μm) planktons varied from 0 to 1.58 × 105 cfu/ml and those of the 60 and 20 μm categories were in the range of 0 to 1.32 × 103 cfu/ml and 0 to 2.82 × 105 cfu/ml respectively. Listeria abundance did not vary significantly with location and season; there was however, significant (P < 0.05; P < 0.01) variance in Listeria abundance with plankton sizes across the locations. Free-living Listeria species were more abundant in the rural and urban xii communities than plankton attached Listeria species; whereas the reverse was the case in the peri-urban community. Prevalence of Listeria in terms of total counts was 100 percent across all sampled locations. Free-living Listeria species showed prevalence ranging from 84-96 percent across the sampling locations; while Listeria species attached to large (180 μm) planktons exhibited prevalence ranging from 75 percent to 90 percent. The prevalence of medium-sized (60 μm) plankton associated Listeria species varied between 58 percent and 92.5 percent; whereas those of Listeria species attached to small (20 μm) planktons ranged from 65-100 percent across all three communities. Listeria prevalence was generally a reflection of the turbidity of the water system, with free-living Listeria species being more prevalent than plankton associated cells in the relatively less turbid rural and urban waters compared to the more turbid peri-urban waters where plankton attached cells were more prevalent in comparison with their free living counterparts The final treated effluent quality fell short of recommended standards for turbidity, chemical oxygen demand and phosphate across all three communities. In addition, the final effluent of the rural treatment plant also fell short of recommended standard for NO3, while that of the urban treatment plant did not comply with acceptable limits for dissolved oxygen and nitrite. Other physicochemical parameters were compliant with set standards after treatment. An inverse relationship was observed between chlorine residual and listerial density across the sampled facilities; the effect of chlorine was however not enough to eliminate the pathogen from the water systems. At the urban treatment plant and its receiving watershed, pH, temperature, EC, turbidity, TDS, DO, and nitrate varied significantly with season and sampling point (P < 0.05; P < 0.01). Salinity also varied significantly with sampling point (P < 0.01), while COD and nitrite varied significantly with season (P < 0.05). Although, the treated effluent fell within recommended water quality standard for pH, TDS, nitrate and nitrite, it fell short of stipulated standards for other parameters. Whereas the microbial quality of the secondary treated effluent at this (urban) facility fell short of recommended standard after secondary treatment, its physicochemical quality were generally compliant with recommended standards for reuse wastewater in agriculture and aquaculture. Listeria pathogens isolated from effluents of the rural wastewater facility were sensitive to 11 (55 percent) of the 20 test antibiotics, and showed varying (7-71 percent) levels of resistance to 8 antibiotics; whereas those isolated from the peri-urban community showed sensitivity to 6 (30 percent) of the 20 test antibiotics, and varying (6-94 percent) levels of resistance to 12 antibiotics; while the urban effluent isolates were sensitive to 3 (15 percent) of the 20 test antibiotics, and showed varying (4.5-91 percent) levels of resistance to 17 antibiotics. Multiple antibiotic resistances involving 78.5-100 percent of isolates and antibiotics combination ranging from 2-10 antibiotics was observed across the sampled locations. Penicillin G and ampicillin showed remarkably high (64-91 percent) phenotypic resistance across the three sampled facilities. Other antibiotics, to which isolates showed significant resistance, were linezolid (22-88 percent); erythromycin (43-94 percent) and sulphamethoxazole (7-94 percent). Two of the 14 Listeria strains isolated from the rural effluents were positive for ereA and sul1 antibiotic resistance genes; while sulII genes were detected in five of the 23 Listeria isolates from the urban effluent and none was detected in isolates from the peri-urban community. The presence of antimicrobial resistance genes in the isolates did not correlate with phenotypic antibiotic resistance. The current study demonstrated that Listeria pathogens easily survived the activated sludge treatment process as free-living and plankton attached entities and suggests that municipal wastewater treatment plants are a significant source of multiple resistant Listeria pathogens in the South African aquatic milieu. While the physicochemical quality of the urban final effluent suggests that it is a major source of pollution to the receiving watershed, the secondary effluent quality demonstrated a great potential for use in agriculture and aquaculture.
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- Date Issued: 2010