Localizing selected endocytosis protein candidates in Plasmodium falciparum using GFP-tagged fusion constructs
- Authors: Basson, Travis
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/2680 , vital:20316
- Description: Malaria is a mosquito-borne infectious disease caused by several obligate intracellular protozoan parasites in the Plasmodium genus, with Plasmodium falciparum causing the most widespread cases and malaria deaths. In 2013 there were approximately 190 million cases of the disease and between 584,000 and 855,000 deaths. It is essential to identify novel drug targets and develop novel drug candidates due to the increase in resistance of P. falciparum parasites to the current arsenal of antimalarial drugs. Endocytosis is an essential process in eukaryotic cells in which the external environment is internalized by the cell in order to obtain various particles from the extracellular space. This extracellular cytoplasm is internalized in membrane-bound invaginations at the plasma membrane. During the blood stage of malaria infection, the parasite requires nutrients from the host red blood cell. To obtain these nutrients, the parasite internalizes haemoglobin in large amounts and degrades it in an acidic, lysosome-like organelle, known as the digestive vacuole. Whilst the exact molecular mechanism of malaria parasite endocytosis is not yet fully understood, a number of proteins have been suggested to be involved. The most expedient approach in identifying candidate endocytosis proteins is to investigate parasite homologues of proteins known to be involved in endocytosis in mammalian cells. The three proteins selected for investigation in this study were the P. falciparum homologues of coronin, dynamin 2, and μ4. The coding sequences for the candidate endocytosis proteins were amplified by PCR and cloned into the pARL2-GFP expression vector. P. falciparum 3D7 parasites were transfected with these vectors and the episomal expression of full-length GFP-tagged fusion protein was confirmed by Western blot analysis using commercially available anti-GFP antibodies. Microscopic analysis of live parasites using fluorescence and confocal microscopy was used to determine the localization of the candidate endocytosis proteins. Coronin appeared to display diffuse cytoplasmic GFP localization during the trophozoite stage, arguing against a role in endocytosis. However, distinct localization during the schizont stage at what appears to be the inner membrane complex was observed. Coronin is thus likely required to coordinate the formation of the actin network between the merozoite IMC and the plasma membrane on which the glideosome is dependant for generating the motile forces required for the merozoite motility and invasion of RBCs. Dynamin 2 displayed localization at three potential locii: the parasite periphery (plasma membrane), punctuate regions within the cytoplasm (potentially at membrane bound organelles) and at the parasite food vacuole. The data suggested that dynamin 2 is involved in endocytosis and membrane trafficking in a similar manner to classical dynamins, potentially as a vesicle scission molecule at the plasma membrane, mediating vesicle formation at the food vacuole to recycle membrane to the plasma membrane, and possibly mitochondria organelle division. μ4 displayed transient localization, cycling between cytosolic localization, and localization to distinct regions at the plasma membrane and the food vacuole. Localization of Pfμ4 to the plasma membrane is indicative of a role for μ4 as a part of an adaptor protein (AP) complex which may be responsible for recruitment of clathrin to initiate endocytosis in a manner similar to mammalian AP-2. As was observed with PfDYN2, Pfμ4 localizes to the FV, which suggests that Pfμ4 forms part of a coat complex that mediates the formation of vesicles that recycle membrane from the FV to the parasite plasma membrane. This study showed that expressing proteins as full-length GFP-tagged fusion constructs is an effective approach in the early stages of determining the localization and function of P. falciparum proteins in vitro, and distinguishing between candidates that have a potential role in endocytosis and those that are unlikely to do so.
- Full Text:
- Date Issued: 2016
- Authors: Basson, Travis
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/2680 , vital:20316
- Description: Malaria is a mosquito-borne infectious disease caused by several obligate intracellular protozoan parasites in the Plasmodium genus, with Plasmodium falciparum causing the most widespread cases and malaria deaths. In 2013 there were approximately 190 million cases of the disease and between 584,000 and 855,000 deaths. It is essential to identify novel drug targets and develop novel drug candidates due to the increase in resistance of P. falciparum parasites to the current arsenal of antimalarial drugs. Endocytosis is an essential process in eukaryotic cells in which the external environment is internalized by the cell in order to obtain various particles from the extracellular space. This extracellular cytoplasm is internalized in membrane-bound invaginations at the plasma membrane. During the blood stage of malaria infection, the parasite requires nutrients from the host red blood cell. To obtain these nutrients, the parasite internalizes haemoglobin in large amounts and degrades it in an acidic, lysosome-like organelle, known as the digestive vacuole. Whilst the exact molecular mechanism of malaria parasite endocytosis is not yet fully understood, a number of proteins have been suggested to be involved. The most expedient approach in identifying candidate endocytosis proteins is to investigate parasite homologues of proteins known to be involved in endocytosis in mammalian cells. The three proteins selected for investigation in this study were the P. falciparum homologues of coronin, dynamin 2, and μ4. The coding sequences for the candidate endocytosis proteins were amplified by PCR and cloned into the pARL2-GFP expression vector. P. falciparum 3D7 parasites were transfected with these vectors and the episomal expression of full-length GFP-tagged fusion protein was confirmed by Western blot analysis using commercially available anti-GFP antibodies. Microscopic analysis of live parasites using fluorescence and confocal microscopy was used to determine the localization of the candidate endocytosis proteins. Coronin appeared to display diffuse cytoplasmic GFP localization during the trophozoite stage, arguing against a role in endocytosis. However, distinct localization during the schizont stage at what appears to be the inner membrane complex was observed. Coronin is thus likely required to coordinate the formation of the actin network between the merozoite IMC and the plasma membrane on which the glideosome is dependant for generating the motile forces required for the merozoite motility and invasion of RBCs. Dynamin 2 displayed localization at three potential locii: the parasite periphery (plasma membrane), punctuate regions within the cytoplasm (potentially at membrane bound organelles) and at the parasite food vacuole. The data suggested that dynamin 2 is involved in endocytosis and membrane trafficking in a similar manner to classical dynamins, potentially as a vesicle scission molecule at the plasma membrane, mediating vesicle formation at the food vacuole to recycle membrane to the plasma membrane, and possibly mitochondria organelle division. μ4 displayed transient localization, cycling between cytosolic localization, and localization to distinct regions at the plasma membrane and the food vacuole. Localization of Pfμ4 to the plasma membrane is indicative of a role for μ4 as a part of an adaptor protein (AP) complex which may be responsible for recruitment of clathrin to initiate endocytosis in a manner similar to mammalian AP-2. As was observed with PfDYN2, Pfμ4 localizes to the FV, which suggests that Pfμ4 forms part of a coat complex that mediates the formation of vesicles that recycle membrane from the FV to the parasite plasma membrane. This study showed that expressing proteins as full-length GFP-tagged fusion constructs is an effective approach in the early stages of determining the localization and function of P. falciparum proteins in vitro, and distinguishing between candidates that have a potential role in endocytosis and those that are unlikely to do so.
- Full Text:
- Date Issued: 2016
Cosmological structure formation using spectral methods
- Authors: Funcke, Michelle
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/2969 , vital:20348
- Description: Numerical simulations are becoming an increasingly important tool for understanding the growth and development of structure in the universe. Common practice is to discretize the space-time using physical variables. The discreteness is embodied by considering the dynamical variables as fields on a fixed spatial and time resolution, or by constructing the matter fields by a large number of particles which interact gravitationally (N-body methods). Recognizing that the physical quantities of interest are related to the spectrum of perturbations, we propose an alternate discretization in the frequency domain, using standard spectral methods. This approach is further aided by periodic boundary conditions which allows a straightforward decomposition of variables in a Fourier basis. Fixed resources require a high-frequency cut-off which lead to aliasing effects in non-linear equations, such as the ones considered here. This thesis describes the implementation of a 3D cosmological model based on Newtonian hydrodynamic equations in an expanding background. Initial data is constructed as a spectrum of perturbations, and evolved in the frequency domain using a pseudo-spectral evolution scheme and an explicit Runge-Kutta time integrator. The code is found to converge for both linear and non-linear evolutions, and the convergence rate is determined. The correct growth rates expected from analytical calculations are recovered in the linear case. In the non-linear model, we observe close correspondence with linear growth and are able to monitor the growth on features associated with the non-linearity. High-frequency aliasing effects were evident in the non-linear evolutions, leading to a study of two potential resolutions to this problem: a boxcar filter which adheres to“Orszag’s two thirds rule” and an exponential window function, the exponential filter suggested by Hou and Li [1], and a shifted version of the exponential filter suggested, which has the potential to alleviate high frequency- ripples resulting from the Gibbs’ phenomenon. We found that the filters were somewhat successful at reducing aliasing effects but that the Gibbs’ phenomenon could not be entirely removed by the choice of filters.
- Full Text:
- Date Issued: 2016
- Authors: Funcke, Michelle
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/2969 , vital:20348
- Description: Numerical simulations are becoming an increasingly important tool for understanding the growth and development of structure in the universe. Common practice is to discretize the space-time using physical variables. The discreteness is embodied by considering the dynamical variables as fields on a fixed spatial and time resolution, or by constructing the matter fields by a large number of particles which interact gravitationally (N-body methods). Recognizing that the physical quantities of interest are related to the spectrum of perturbations, we propose an alternate discretization in the frequency domain, using standard spectral methods. This approach is further aided by periodic boundary conditions which allows a straightforward decomposition of variables in a Fourier basis. Fixed resources require a high-frequency cut-off which lead to aliasing effects in non-linear equations, such as the ones considered here. This thesis describes the implementation of a 3D cosmological model based on Newtonian hydrodynamic equations in an expanding background. Initial data is constructed as a spectrum of perturbations, and evolved in the frequency domain using a pseudo-spectral evolution scheme and an explicit Runge-Kutta time integrator. The code is found to converge for both linear and non-linear evolutions, and the convergence rate is determined. The correct growth rates expected from analytical calculations are recovered in the linear case. In the non-linear model, we observe close correspondence with linear growth and are able to monitor the growth on features associated with the non-linearity. High-frequency aliasing effects were evident in the non-linear evolutions, leading to a study of two potential resolutions to this problem: a boxcar filter which adheres to“Orszag’s two thirds rule” and an exponential window function, the exponential filter suggested by Hou and Li [1], and a shifted version of the exponential filter suggested, which has the potential to alleviate high frequency- ripples resulting from the Gibbs’ phenomenon. We found that the filters were somewhat successful at reducing aliasing effects but that the Gibbs’ phenomenon could not be entirely removed by the choice of filters.
- Full Text:
- Date Issued: 2016
Reproductive biology of important invasive plants in the Eastern Cape Province of South Africa
- Authors: Thorne, Cara-Jayne
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/3683 , vital:20535
- Description: Baker’s rule predicts species capable of uniparental reproduction are more likely to establish after long distance dispersal (or introduction in the case of invasive plants), thus the ability to undergo autonomous self-pollination should promote colonization. An investigation into the reproductive biology of eleven invasive species in the Eastern Cape Province of South Africa between 2012 and 2014 showed strong support for Baker’s law. Breeding system results showed evidence of self-compatibility in eight species, ten species were capable of autonomous self-pollination, and only three species showed evidence of varying levels of self-incompatibility. These results provide evdence that autonomous self-pollination occurs more frequently among invasive species, self-compatible species more frequently become invasive compared with self-incompatible species and that autogamous species should have a larger invasive range. Co-opting suitable local pollinators may be problematic for invasive plants, especially those with highly specialized pollination systems. The species investigated appear to be largely independent of pollinators, mostly setting seed in the absence of pollinators. Despite this, all eleven invasive plant species are regularly visited by a variety of generalist pollinators including Apis mellifera, Xylocopa bees and Allodapini species. Pollinators all carried substantial pollen loads, even managing to extract pollen from more specialized plants, such as the poricidal anthers of Solanum species, and frequently came into contact with both anthers and stigmas. Considering most of theses species are capable of autonomous self-pollination, their reliance on pollinators may be low. Even the most self-incompatible species, Passiflora caerulea, appears to have successfully co-opted local pollinators (honeybees and carpenter bees), ensuring successful pollination and seed set. The ability for cross-pollination by local pollinators allows for some degree of genetic variation within invasive plant populations, especially for self-incompatible species. Inadequate pollen deposition by unreliable or inefficient pollinators, or reduced resource availability, can result in pollen limitation. Invasive plant species may be especially susceptible, with three of the plant species investiagted showing possible pollen limitation at the level of seed set, while the remaining nine invasive plant species showed no evidence of pollen limitation in South Africa. The ability to utilize uniparental reproduction (as Baker’s law predicted), and co-opt local pollinators has allowed invasive plants in the Eastern Cape to successfully establish and persist after introduction. Hence, the inclusion of reproductive traits of plants should therefore be included in risk assessments for future plant invaders.
- Full Text:
- Date Issued: 2016
- Authors: Thorne, Cara-Jayne
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/3683 , vital:20535
- Description: Baker’s rule predicts species capable of uniparental reproduction are more likely to establish after long distance dispersal (or introduction in the case of invasive plants), thus the ability to undergo autonomous self-pollination should promote colonization. An investigation into the reproductive biology of eleven invasive species in the Eastern Cape Province of South Africa between 2012 and 2014 showed strong support for Baker’s law. Breeding system results showed evidence of self-compatibility in eight species, ten species were capable of autonomous self-pollination, and only three species showed evidence of varying levels of self-incompatibility. These results provide evdence that autonomous self-pollination occurs more frequently among invasive species, self-compatible species more frequently become invasive compared with self-incompatible species and that autogamous species should have a larger invasive range. Co-opting suitable local pollinators may be problematic for invasive plants, especially those with highly specialized pollination systems. The species investigated appear to be largely independent of pollinators, mostly setting seed in the absence of pollinators. Despite this, all eleven invasive plant species are regularly visited by a variety of generalist pollinators including Apis mellifera, Xylocopa bees and Allodapini species. Pollinators all carried substantial pollen loads, even managing to extract pollen from more specialized plants, such as the poricidal anthers of Solanum species, and frequently came into contact with both anthers and stigmas. Considering most of theses species are capable of autonomous self-pollination, their reliance on pollinators may be low. Even the most self-incompatible species, Passiflora caerulea, appears to have successfully co-opted local pollinators (honeybees and carpenter bees), ensuring successful pollination and seed set. The ability for cross-pollination by local pollinators allows for some degree of genetic variation within invasive plant populations, especially for self-incompatible species. Inadequate pollen deposition by unreliable or inefficient pollinators, or reduced resource availability, can result in pollen limitation. Invasive plant species may be especially susceptible, with three of the plant species investiagted showing possible pollen limitation at the level of seed set, while the remaining nine invasive plant species showed no evidence of pollen limitation in South Africa. The ability to utilize uniparental reproduction (as Baker’s law predicted), and co-opt local pollinators has allowed invasive plants in the Eastern Cape to successfully establish and persist after introduction. Hence, the inclusion of reproductive traits of plants should therefore be included in risk assessments for future plant invaders.
- Full Text:
- Date Issued: 2016
Crop rotation and crop residue management effects under no till on the soil quality of two ecotopes in the Eastern Cape, South Africa
- Authors: Isaac, Gura
- Date: 2016
- Subjects: Crop rotation Crops and soils Soil fertility
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/2934 , vital:28144
- Description: The degradation of soil quality due to undesirable farming practices has reached alarming scales in the Eastern Cape and this has had negative repercussions on soil productivity and the environment in general. There is growing evidence that conservation agriculture (CA) practices involving minimal mechanical disturbance, maintaining permanent surface cover and embracing diverse crop rotations increase soil organic carbon (SOC) and therefore has potential to mitigate soil quality deterioration. A study was carried out at two sites located in two ecotopes to investigate the effects of crop residue retention and crop rotations in a no till system on overall soil quality using the Soil Management Assessment Framework (SMAF) as the soil quality assessment tool. The CA study trials were laid out in 2012 at two different locations, one at the Phandulwazi Agricultural High school within the Phandulwazi Jozini ecotope and the other one at University of Fort Hare Research Farm within the Alice Jozini ecotope. The experiment was laid out as a split-split plot arrangement in a randomized complete block design with three replicates. Tillage treatments were applied on the main plots while crop rotation treatments were applied as subplots. Crop residue retention treatments were applied as sub-sub plots. The rotational treatments were maize-fallow-maize (MFM), maize-fallow-soybean (MFS), maize-wheat-maize (MWM) and maize-wheat-soybean (MWS). The initial assessment of the overall soil quality of the two ecotopes using the SMAF soil quality index (SQI) revealed that the soils at the Alice site were functioning at 80% while the soils at the Phandulwazi site were functioning at 79 percent of their optimum capacity. The slight difference in the soil quality of the two ecotopes could be attributed to their different soil organic C contents where the Alice Jozini ecotope had significantly higher soil organic C contents than the Phandulwazi Jozini ecotope. After 3 years of continuous treatment application, crop residue retention significantly improved most of the measured soil quality parameters. Generally across the sites, more soil organic C, microbial biomass C (MBC), ß-glucosidase (BG) activity, mineral N, extractable P and K, Cu, Zn, Mn, Fe, and macro-aggregates were recorded in treatments where crop residues were retained. Crop rotations alone did not have a significant impact on most of the measured soil quality indicators. The crop rotations influenced significantly the availability of mineral N across the two sites, highlighting the importance of using a legume in rotations on available N for the subsequent crops. Most of the measured soil attributes were not significantly influenced after 3 years of continuously applying combined treatment of CA components. Mineral N (NO3 + NH4), K, Zn and Fe were significantly impacted on by the interactions of CA components at the Phandulwazi site, while N, Cu, Zn and Mn were significantly increased at the Alice site. Low response of SOC to combined CA treatments in the short-term prompted the need to examine treatment effects on individual soil carbon fractions. The interaction of crop rotation and residue management techniques were significant on the fine particulate organic matter – C fractions and microbially respired C. These soil C fractions were more sensitive to short-term treatments of combined CA components than SOC and MBC, therefore they can be used as short-term indicators of CA effects on SOM. Soil organic carbon, MBC, extractable P and K, soil pH, EC, b, AGS (aggregate stability) and BG activity were measured and the Soil Management Assessment Framework (SMAF) used to calculate soil quality index (SQI) values for each treatment. The combination of the crop rotations with crop residue retention showed the potential to significantly improve SQI values in the long term. The highest soil quality improvement at both sites was achieved by the maize-wheat-soybean (MWS) rotation with crop residue retention.
- Full Text:
- Date Issued: 2016
- Authors: Isaac, Gura
- Date: 2016
- Subjects: Crop rotation Crops and soils Soil fertility
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/2934 , vital:28144
- Description: The degradation of soil quality due to undesirable farming practices has reached alarming scales in the Eastern Cape and this has had negative repercussions on soil productivity and the environment in general. There is growing evidence that conservation agriculture (CA) practices involving minimal mechanical disturbance, maintaining permanent surface cover and embracing diverse crop rotations increase soil organic carbon (SOC) and therefore has potential to mitigate soil quality deterioration. A study was carried out at two sites located in two ecotopes to investigate the effects of crop residue retention and crop rotations in a no till system on overall soil quality using the Soil Management Assessment Framework (SMAF) as the soil quality assessment tool. The CA study trials were laid out in 2012 at two different locations, one at the Phandulwazi Agricultural High school within the Phandulwazi Jozini ecotope and the other one at University of Fort Hare Research Farm within the Alice Jozini ecotope. The experiment was laid out as a split-split plot arrangement in a randomized complete block design with three replicates. Tillage treatments were applied on the main plots while crop rotation treatments were applied as subplots. Crop residue retention treatments were applied as sub-sub plots. The rotational treatments were maize-fallow-maize (MFM), maize-fallow-soybean (MFS), maize-wheat-maize (MWM) and maize-wheat-soybean (MWS). The initial assessment of the overall soil quality of the two ecotopes using the SMAF soil quality index (SQI) revealed that the soils at the Alice site were functioning at 80% while the soils at the Phandulwazi site were functioning at 79 percent of their optimum capacity. The slight difference in the soil quality of the two ecotopes could be attributed to their different soil organic C contents where the Alice Jozini ecotope had significantly higher soil organic C contents than the Phandulwazi Jozini ecotope. After 3 years of continuous treatment application, crop residue retention significantly improved most of the measured soil quality parameters. Generally across the sites, more soil organic C, microbial biomass C (MBC), ß-glucosidase (BG) activity, mineral N, extractable P and K, Cu, Zn, Mn, Fe, and macro-aggregates were recorded in treatments where crop residues were retained. Crop rotations alone did not have a significant impact on most of the measured soil quality indicators. The crop rotations influenced significantly the availability of mineral N across the two sites, highlighting the importance of using a legume in rotations on available N for the subsequent crops. Most of the measured soil attributes were not significantly influenced after 3 years of continuously applying combined treatment of CA components. Mineral N (NO3 + NH4), K, Zn and Fe were significantly impacted on by the interactions of CA components at the Phandulwazi site, while N, Cu, Zn and Mn were significantly increased at the Alice site. Low response of SOC to combined CA treatments in the short-term prompted the need to examine treatment effects on individual soil carbon fractions. The interaction of crop rotation and residue management techniques were significant on the fine particulate organic matter – C fractions and microbially respired C. These soil C fractions were more sensitive to short-term treatments of combined CA components than SOC and MBC, therefore they can be used as short-term indicators of CA effects on SOM. Soil organic carbon, MBC, extractable P and K, soil pH, EC, b, AGS (aggregate stability) and BG activity were measured and the Soil Management Assessment Framework (SMAF) used to calculate soil quality index (SQI) values for each treatment. The combination of the crop rotations with crop residue retention showed the potential to significantly improve SQI values in the long term. The highest soil quality improvement at both sites was achieved by the maize-wheat-soybean (MWS) rotation with crop residue retention.
- Full Text:
- Date Issued: 2016
Factors that influence the sustainability of rural crop production community projects in the Umzimvubu District
- Authors: Majiki, Fezeka
- Date: 2016
- Subjects: Sustainable agriculture -- South Africa -- Eastern Cape , Economic development projects -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/8089 , vital:24991
- Description: Maize production is the main cropping activity in the Umzimvubu district. This cereal crop is the staple food for the Eastern Cape’s rural communities and accounts for nearly 95 per cent of the crops cultivated in dry-land cropping programmes. Food security in rural areas has been a major concern for the South African government. In attempts to mitigate hunger and poverty, the government has initiated rural development maize production projects. The primary objectives of the projects were to achieve sustainable livelihoods and rural development for the poor. The projects were expected to improve the quality of rural life and provide basic nutritional requirements of the community. Historically the rural poor have had to fend for themselves through subsistence farming in adverse environments. Input costs for farming have become increasingly expensive; this resulted in major challenges for subsistence farming. The crop production projects initiated in the Umzimvubu district have not been sustainable and have fallen short of addressing the needs of the various communities. The study aims to identify the factors that influence the sustainability of the crop production projects in the Umzimvubu district. A triangulation research method was used to provide multiple viewpoints to examine the data; this allows for greater accuracy of the research. The mixed method approach in which the researcher collects and analyses data integrates the findings and draws inferences using both qualitative and quantitative methodology. The quantitative research methodology provided the demographics and biographical data on the participants. The qualitative research methodology concentrated on the focus group discussions that gave an insight into the participants' views, perceptions and concerns. Focus groups were used to examine the factors influencing the sustain-ability of the projects and to explore how these projects are perceived and under-stood by the community and people working on the projects. The research interest is not only in what the project beneficiaries think, but also in why they think as they do. The main data collection was obtained from the focus groups and individual face-to-face interviews with the beneficiaries of the crop projects in the Umzimvubu district. It was found that the farming areas required rehabilitation, were susceptible to erosion and degradation, and lacked adequate land use practices. The beneficiaries of the cropping programmes had small amounts of other crops growing in their individual household gardens for household use in conjunction with the maize received from the maize programmes. The income made from selling maize from the programmes was insignificant and did not contribute substantially to the household needs, as the communities in these projects were still failing to secure adequate food requirements. The maize yields do not substantiate the monetary investment from the beneficiaries. Furthermore, the findings indicated that the beneficiaries do not receive consistent income from the programmes. The participants consisted of large households comprising mainly elderly people who depended on social grants as a regular source of income. These elderly were burdened with taking care of their grandchildren, whose parents were employed in either urban areas or unemployed and formed part of the household. The unemployed young adults also depended on child support grants for income. The maize harvested had to be shared between a large number of community members and the livestock. The findings also suggested that there was dependency on outside contractors for cultivation and other practices. The study found that most of the beneficiaries felt disempowered, as they had not been involved in the decision-making process. Furthermore, policy-makers failed to acknowledge existing indigenous knowledge and practices of the rural communities (i.e. inter-cropping and green mealie harvesting). Indigenous practices should be included into the programmes instead of compelling beneficiaries to adhere to new forms of cultivation. The communities introduction to new large-scale and challenging, highly technological methods resulted in most of the communities being fully dependent on government support and guidance. Training and the empowerment of beneficiaries are imperative. Rural people should be included in development of strategies and the role of the women should be given more recognition. It should be acknowledged that rural households are diverse and that the model cannot apply to each village or community.
- Full Text:
- Date Issued: 2016
- Authors: Majiki, Fezeka
- Date: 2016
- Subjects: Sustainable agriculture -- South Africa -- Eastern Cape , Economic development projects -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/8089 , vital:24991
- Description: Maize production is the main cropping activity in the Umzimvubu district. This cereal crop is the staple food for the Eastern Cape’s rural communities and accounts for nearly 95 per cent of the crops cultivated in dry-land cropping programmes. Food security in rural areas has been a major concern for the South African government. In attempts to mitigate hunger and poverty, the government has initiated rural development maize production projects. The primary objectives of the projects were to achieve sustainable livelihoods and rural development for the poor. The projects were expected to improve the quality of rural life and provide basic nutritional requirements of the community. Historically the rural poor have had to fend for themselves through subsistence farming in adverse environments. Input costs for farming have become increasingly expensive; this resulted in major challenges for subsistence farming. The crop production projects initiated in the Umzimvubu district have not been sustainable and have fallen short of addressing the needs of the various communities. The study aims to identify the factors that influence the sustainability of the crop production projects in the Umzimvubu district. A triangulation research method was used to provide multiple viewpoints to examine the data; this allows for greater accuracy of the research. The mixed method approach in which the researcher collects and analyses data integrates the findings and draws inferences using both qualitative and quantitative methodology. The quantitative research methodology provided the demographics and biographical data on the participants. The qualitative research methodology concentrated on the focus group discussions that gave an insight into the participants' views, perceptions and concerns. Focus groups were used to examine the factors influencing the sustain-ability of the projects and to explore how these projects are perceived and under-stood by the community and people working on the projects. The research interest is not only in what the project beneficiaries think, but also in why they think as they do. The main data collection was obtained from the focus groups and individual face-to-face interviews with the beneficiaries of the crop projects in the Umzimvubu district. It was found that the farming areas required rehabilitation, were susceptible to erosion and degradation, and lacked adequate land use practices. The beneficiaries of the cropping programmes had small amounts of other crops growing in their individual household gardens for household use in conjunction with the maize received from the maize programmes. The income made from selling maize from the programmes was insignificant and did not contribute substantially to the household needs, as the communities in these projects were still failing to secure adequate food requirements. The maize yields do not substantiate the monetary investment from the beneficiaries. Furthermore, the findings indicated that the beneficiaries do not receive consistent income from the programmes. The participants consisted of large households comprising mainly elderly people who depended on social grants as a regular source of income. These elderly were burdened with taking care of their grandchildren, whose parents were employed in either urban areas or unemployed and formed part of the household. The unemployed young adults also depended on child support grants for income. The maize harvested had to be shared between a large number of community members and the livestock. The findings also suggested that there was dependency on outside contractors for cultivation and other practices. The study found that most of the beneficiaries felt disempowered, as they had not been involved in the decision-making process. Furthermore, policy-makers failed to acknowledge existing indigenous knowledge and practices of the rural communities (i.e. inter-cropping and green mealie harvesting). Indigenous practices should be included into the programmes instead of compelling beneficiaries to adhere to new forms of cultivation. The communities introduction to new large-scale and challenging, highly technological methods resulted in most of the communities being fully dependent on government support and guidance. Training and the empowerment of beneficiaries are imperative. Rural people should be included in development of strategies and the role of the women should be given more recognition. It should be acknowledged that rural households are diverse and that the model cannot apply to each village or community.
- Full Text:
- Date Issued: 2016
Exploring how grade 12 Physical Sciences learners make sense of the concepts of work and energy
- Authors: Mapfumo, Alfred Khumbulani
- Date: 2016
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/1363 , vital:20050
- Description: Physical Sciences is one of the subjects in which students perform most poorly in the National Senior Certificate examinations. For example, in the Eastern Cape in 2013, a mere 29.9% of the candidates who sat for the Physical Sciences National Senior Certificate examination managed to achieve a mark of 40% or above (Department of Basic Education, 2014). According to the Chief Markers’ reports (ibid), questions on the topic of Work, Energy and Power are amongst the most poorly answered in the National Senior Certificate examinations. This fact triggered my interest to explore how grade 12 Physical Sciences learners make sense of the concepts of Work and Energy with particular emphasis on the work-energy theorem and its application in problem solving. I carried out the study in a village school in the Queenstown district. The study adopted an interpretive paradigm in which the case study approach was used. Data were generated using a diagnostic test, focus group interviews, video-recorded lessons, analysis of learner journals and a summative test. Analysis of the qualitative data involved identifying themes from the data and using analytical statements that answered the research questions. The study was informed by Vygotsky’s (1978) social constructivism theory, and in particular, the notions of the mediation of learning and the Zone of Proximal Development (ZPD). Learners were given tasks on the work-energy theorem and related concepts and these were designed in such a way that they were situated in the learners’ ZPD, since this is where most powerful learning takes place (Thompson, 2013). The findings of the study revealed that grade 12 Physical Sciences learners do not have sufficient prior knowledge on concepts related to the work-energy theory to successfully make sense of the work-energy theorem. The other finding is that learners construct knowledge of the work-energy theorem and its application collaboratively through group work. In the group discussions learners used isiXhosa and this enhanced their sense making. A number of challenges that make it difficult for learners to solve problems using the work-energy theorem were identified.
- Full Text:
- Date Issued: 2016
- Authors: Mapfumo, Alfred Khumbulani
- Date: 2016
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/1363 , vital:20050
- Description: Physical Sciences is one of the subjects in which students perform most poorly in the National Senior Certificate examinations. For example, in the Eastern Cape in 2013, a mere 29.9% of the candidates who sat for the Physical Sciences National Senior Certificate examination managed to achieve a mark of 40% or above (Department of Basic Education, 2014). According to the Chief Markers’ reports (ibid), questions on the topic of Work, Energy and Power are amongst the most poorly answered in the National Senior Certificate examinations. This fact triggered my interest to explore how grade 12 Physical Sciences learners make sense of the concepts of Work and Energy with particular emphasis on the work-energy theorem and its application in problem solving. I carried out the study in a village school in the Queenstown district. The study adopted an interpretive paradigm in which the case study approach was used. Data were generated using a diagnostic test, focus group interviews, video-recorded lessons, analysis of learner journals and a summative test. Analysis of the qualitative data involved identifying themes from the data and using analytical statements that answered the research questions. The study was informed by Vygotsky’s (1978) social constructivism theory, and in particular, the notions of the mediation of learning and the Zone of Proximal Development (ZPD). Learners were given tasks on the work-energy theorem and related concepts and these were designed in such a way that they were situated in the learners’ ZPD, since this is where most powerful learning takes place (Thompson, 2013). The findings of the study revealed that grade 12 Physical Sciences learners do not have sufficient prior knowledge on concepts related to the work-energy theory to successfully make sense of the work-energy theorem. The other finding is that learners construct knowledge of the work-energy theorem and its application collaboratively through group work. In the group discussions learners used isiXhosa and this enhanced their sense making. A number of challenges that make it difficult for learners to solve problems using the work-energy theorem were identified.
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- Date Issued: 2016
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