Assessing invasive alien aquatic plant species, phytoremediation effects using biological indicators in the Swartkops River system
- Authors: Tshithukhe, Getrude
- Date: 2020
- Subjects: Aquatic weeds -- Biological control -- South Africa -- Eastern Cape , Alien plants -- Biological control -- South Africa -- Eastern Cape , Phytoremediation -- South Africa
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/167665 , vital:41501
- Description: Pollution effluents in freshwater ecosystems are becoming increasingly ubiquitous as a result of cumulative anthropogenic activities, such as wastewater treatments works, and industrial, agricultural and mining activities. These activities are more noticeable in urban river atchments where there is greater human population densities and industrial developments. The ecological effects of anthropogenic activities on freshwater ecosystems include: excessive deposition of contaminants such as nutrients, pharmaceuticals, microplastics and other chemicals, which change physicochemical properties, causing a decline in aquatic biodiversity. These effects, impact negatively on the resilience of freshwater, making the systems vulnerable to invasion by alien aquatic plants. Ultimately, the loss of local biodiversity associated with the invasive alien aquatic plants (IAAP) results in a loss of some ecosystem goods and services. The Swartkops River system, Eastern Cape Province, drains most of the neighbouring formal and informal settlements, agricultural lands and industries, and hence is exposed to water pollution from human activities along the river catchment. Various water quality assessments are needed to evaluate the extent of pollutants and their impacts on the river ecosystem. Phytoremediation is one approach employed internationally for removing harmful nutrients and chemicals in freshwater ecosystems. Most studies measure the success of phytoremediation through measuring the reduction of contaminants in water or soil chemistry in mesocosm settings, which may not take into account all the important environmental factors that exist in the field. The present study assesses the phytoremediation potential of Pontederia (Eichhornia) crassipes and Salvinia molesta by evaluating water and sediment chemistry, periphyton and aquatic macroinvertebrate community recovery along seven field sites (excluding IAAP species mats sites) located upstream and downstream IAAP species mats on the Swartkops River between April and September 2018. Water and sediment samples were collected once monthly on ten seven field sites, including the IAAP species mat sites. Periphyton and aquatic macroinvertebrates were collected on seven sites, excluding the IAAP mat sites. Pontederia crassipes and S. molesta infestation in Swartkops River showed positive phytoremediation results and improved some water and sediment chemistry in the downstream treatments as compared to upstream treatments. Although there were some fluctuations with some variables, important water and sediment chemistry were reduced downstream. By contrast, biological assessment results did not show any response to the presence of IAAP species and phytoremediation. Periphyton and aquatic macroinvertebrates diversity and community assemblages were more influenced by water quality. Although IAAP species did provide improvement in water and sediments chemistry, multiple effluent point and non-point sources in Swartkops outpaced phytoremediation. Taxa evenness and relative taxa abundance showed significant differences between the upstream and downstream sites, however taxa richness and Shannon’s diversity showed no significant differences, indicating no relative recovery in biodiversity for either periphyton or aquatic macroinvertebrates. Similarly, the upstream and downstream sites showed similar periphyton and aquatic macroinvertebrates assemblages structure, all dominated by pollution tolerant taxa, thus indicating no functional diversity improvement down river; because of improvement in water chemistry downstream sites, it was expected that periphyton and aquatic macroinvertebrates assemblage structure would also improve at these downstream sites.It is possible that the phytoremediation process is outpaced by effluent discharges, given the multiple sources and distance between upstream and downstream mat sites. The study showed phytoremediation potential but the results were not indicated by biological indicators. A replica study conducted on a moderately disturbed river system is recommended to measure the success and recovery of biological indicators and assemblage composition following IAAP species phytoremediation; a moderately disturbed river compared to a largely disturbed river will broaden findings and look at differences for a wider application of phytoremediation.
- Full Text:
- Authors: Tshithukhe, Getrude
- Date: 2020
- Subjects: Aquatic weeds -- Biological control -- South Africa -- Eastern Cape , Alien plants -- Biological control -- South Africa -- Eastern Cape , Phytoremediation -- South Africa
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/167665 , vital:41501
- Description: Pollution effluents in freshwater ecosystems are becoming increasingly ubiquitous as a result of cumulative anthropogenic activities, such as wastewater treatments works, and industrial, agricultural and mining activities. These activities are more noticeable in urban river atchments where there is greater human population densities and industrial developments. The ecological effects of anthropogenic activities on freshwater ecosystems include: excessive deposition of contaminants such as nutrients, pharmaceuticals, microplastics and other chemicals, which change physicochemical properties, causing a decline in aquatic biodiversity. These effects, impact negatively on the resilience of freshwater, making the systems vulnerable to invasion by alien aquatic plants. Ultimately, the loss of local biodiversity associated with the invasive alien aquatic plants (IAAP) results in a loss of some ecosystem goods and services. The Swartkops River system, Eastern Cape Province, drains most of the neighbouring formal and informal settlements, agricultural lands and industries, and hence is exposed to water pollution from human activities along the river catchment. Various water quality assessments are needed to evaluate the extent of pollutants and their impacts on the river ecosystem. Phytoremediation is one approach employed internationally for removing harmful nutrients and chemicals in freshwater ecosystems. Most studies measure the success of phytoremediation through measuring the reduction of contaminants in water or soil chemistry in mesocosm settings, which may not take into account all the important environmental factors that exist in the field. The present study assesses the phytoremediation potential of Pontederia (Eichhornia) crassipes and Salvinia molesta by evaluating water and sediment chemistry, periphyton and aquatic macroinvertebrate community recovery along seven field sites (excluding IAAP species mats sites) located upstream and downstream IAAP species mats on the Swartkops River between April and September 2018. Water and sediment samples were collected once monthly on ten seven field sites, including the IAAP species mat sites. Periphyton and aquatic macroinvertebrates were collected on seven sites, excluding the IAAP mat sites. Pontederia crassipes and S. molesta infestation in Swartkops River showed positive phytoremediation results and improved some water and sediment chemistry in the downstream treatments as compared to upstream treatments. Although there were some fluctuations with some variables, important water and sediment chemistry were reduced downstream. By contrast, biological assessment results did not show any response to the presence of IAAP species and phytoremediation. Periphyton and aquatic macroinvertebrates diversity and community assemblages were more influenced by water quality. Although IAAP species did provide improvement in water and sediments chemistry, multiple effluent point and non-point sources in Swartkops outpaced phytoremediation. Taxa evenness and relative taxa abundance showed significant differences between the upstream and downstream sites, however taxa richness and Shannon’s diversity showed no significant differences, indicating no relative recovery in biodiversity for either periphyton or aquatic macroinvertebrates. Similarly, the upstream and downstream sites showed similar periphyton and aquatic macroinvertebrates assemblages structure, all dominated by pollution tolerant taxa, thus indicating no functional diversity improvement down river; because of improvement in water chemistry downstream sites, it was expected that periphyton and aquatic macroinvertebrates assemblage structure would also improve at these downstream sites.It is possible that the phytoremediation process is outpaced by effluent discharges, given the multiple sources and distance between upstream and downstream mat sites. The study showed phytoremediation potential but the results were not indicated by biological indicators. A replica study conducted on a moderately disturbed river system is recommended to measure the success and recovery of biological indicators and assemblage composition following IAAP species phytoremediation; a moderately disturbed river compared to a largely disturbed river will broaden findings and look at differences for a wider application of phytoremediation.
- Full Text:
Assessing sediment particle-size effects on benthic algal colonisation and total carbohydrate production
- Dalu, Tatenda, Cuthbert, Ross N, Chavalala, Tiyisani L, Froneman, P William, Wasserman, Ryan J
- Authors: Dalu, Tatenda , Cuthbert, Ross N , Chavalala, Tiyisani L , Froneman, P William , Wasserman, Ryan J
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/466815 , vital:76789 , https://doi.org/10.1016/j.scitotenv.2019.136348
- Description: Increased sedimentation and siltation associated with anthropogenic environmental change may alter microbial biofilms and the carbohydrates they produce, with potential bottom-up effects in these ecosystems. The present study aimed to examine to what extent carbohydrate (associated with biofilm exopolymer) concentration and benthic algal biomass vary among different sediment types (size-structure categories) using a microcosm experiment conducted over a period of 28 days. Substrate treatment and time had a significant effect on the total chlorophyll-a concentrations, whilst a significant interaction was present in the case of total sediment carbohydrates. Total sediment carbohydrates did not relate significantly to chlorophyll-a concentrations overall, nor for any substrate treatments owing to a non-significant ‘chlorophyll-a × substrate’ interaction term. The diatom community characteristics across sediment sizes were unique for each treatment in our study, with unique dominant diatom taxa compositions within each sediment size class. The finest sediment particle-size (greater than 63 μm) may be the least stable, most likely due to lower binding. We anticipate that the current study findings will lead to a better understanding of how different sediment types due to sedimentation and siltation will impact on primary productivity and the composition of diatom communities in aquatic systems.
- Full Text:
- Authors: Dalu, Tatenda , Cuthbert, Ross N , Chavalala, Tiyisani L , Froneman, P William , Wasserman, Ryan J
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/466815 , vital:76789 , https://doi.org/10.1016/j.scitotenv.2019.136348
- Description: Increased sedimentation and siltation associated with anthropogenic environmental change may alter microbial biofilms and the carbohydrates they produce, with potential bottom-up effects in these ecosystems. The present study aimed to examine to what extent carbohydrate (associated with biofilm exopolymer) concentration and benthic algal biomass vary among different sediment types (size-structure categories) using a microcosm experiment conducted over a period of 28 days. Substrate treatment and time had a significant effect on the total chlorophyll-a concentrations, whilst a significant interaction was present in the case of total sediment carbohydrates. Total sediment carbohydrates did not relate significantly to chlorophyll-a concentrations overall, nor for any substrate treatments owing to a non-significant ‘chlorophyll-a × substrate’ interaction term. The diatom community characteristics across sediment sizes were unique for each treatment in our study, with unique dominant diatom taxa compositions within each sediment size class. The finest sediment particle-size (greater than 63 μm) may be the least stable, most likely due to lower binding. We anticipate that the current study findings will lead to a better understanding of how different sediment types due to sedimentation and siltation will impact on primary productivity and the composition of diatom communities in aquatic systems.
- Full Text:
Assessment of taste masking of captopril by ion-exchange resins using electronic gustatory system
- Chikukwa, Mellisa T R, Wesoly, Malgorzata, Korzeniowska, Aleksandra B, Ciosek-Skibinska, Patrycja, Walker, Roderick B, Khamanga, Sandile M M
- Authors: Chikukwa, Mellisa T R , Wesoly, Malgorzata , Korzeniowska, Aleksandra B , Ciosek-Skibinska, Patrycja , Walker, Roderick B , Khamanga, Sandile M M
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/184710 , vital:44265 , xlink:href="https://doi.org/10.1080/10837450.2019.1687520"
- Description: The objective of the study was to mask the unpleasant taste of captopril (CPT). Taste masking was achieved by complexation of CPT with a basic ion exchange resin, Dowex® 66, using the batch method. Dowex® 66 was used for the adsorption of CPT, and physical and chemical parameters of the CPT resinates complex were evaluated. A central composite design was used to generate the experiments for the manufacture of resinates using different process and formulation variables. In vitro dissolution studies were performed for 2 h in 0.01N HCl (pH 1.6) using USP Apparatus I. The compatibility of CPT and the resin was evaluated by Fourier transform infrared (FTIR), differential scanning calorimetry (DSC), and powder X-ray diffraction (PXRD). The resinates were evaluated for micromeritic properties and further characterised using FTIR, DSC, and PXRD. Response surface methodology was used to determine the significance of input variables on the CPT content and release. The CPT resin ratio was found to have a significant impact on content of the resinates and on CPT release. The formulations were also studied for taste masking ability by means of an electronic gustatory system – electronic tongue.
- Full Text:
- Authors: Chikukwa, Mellisa T R , Wesoly, Malgorzata , Korzeniowska, Aleksandra B , Ciosek-Skibinska, Patrycja , Walker, Roderick B , Khamanga, Sandile M M
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/184710 , vital:44265 , xlink:href="https://doi.org/10.1080/10837450.2019.1687520"
- Description: The objective of the study was to mask the unpleasant taste of captopril (CPT). Taste masking was achieved by complexation of CPT with a basic ion exchange resin, Dowex® 66, using the batch method. Dowex® 66 was used for the adsorption of CPT, and physical and chemical parameters of the CPT resinates complex were evaluated. A central composite design was used to generate the experiments for the manufacture of resinates using different process and formulation variables. In vitro dissolution studies were performed for 2 h in 0.01N HCl (pH 1.6) using USP Apparatus I. The compatibility of CPT and the resin was evaluated by Fourier transform infrared (FTIR), differential scanning calorimetry (DSC), and powder X-ray diffraction (PXRD). The resinates were evaluated for micromeritic properties and further characterised using FTIR, DSC, and PXRD. Response surface methodology was used to determine the significance of input variables on the CPT content and release. The CPT resin ratio was found to have a significant impact on content of the resinates and on CPT release. The formulations were also studied for taste masking ability by means of an electronic gustatory system – electronic tongue.
- Full Text:
Assessment of the microbial quality of various domestic rainwater harvesting systems and the suitability of a nano based treatment method
- Authors: Malema, Mokaba Shirley
- Date: 2020
- Language: English
- Type: thesis , text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/110218 , vital:33249 , https://dx.doi.org/10.21504/10962/110218
- Description: Thesis (PhD)--Rhodes University, Faculty of Science, Chemistry, 2020. , In most developing countries, people from rural and peri-urban settlements depend on harvested rainwater (HRW) as an alternative water source for drinking and other household purposes. Despite this reliance, there is little monitoring of the microbial quality of HRW in these areas. The most important issue in relation to using untreated harvested rainwater for drinking and other domestic purposes is the potential public health risks associated with microbial pathogens. Unlike chemical contamination, microbial contamination my lead to disease occurring rapidly, hence the need for frequent monitoring. Thus, the current study investigated the microbial quality of various domestic rainwater harvesting systems and the suitability of a nano based treatment method. The first experiments involved determining the microbial (Escherichia coli) and physicochemical quality (pH, turbidity, nitrate and chemical oxygen demand (COD)) of HRW in the Eastern Cape Province, South Africa. Samples were collected from 11 tanks situated at the Rhodes University, Kenton-on-sea (coastal) and in homes in the Grahamstown area on a weekly basis between June and September 2016. The Colilert-18®/Quanti-tray® 2000 system was used for enumeration of E. coli while physicochemical parameters were measured using commercial kits. Results showed that all samples were contaminated with varying concentrations of E. coli ranging from 7 to 1055 MPN/100 mL. Physicochemical analysis revealed that pH ranged from 5.6 to 7.6 and Turbidity values obtained for all tanks were below 5 NTU except for tank 4 (5.12 ± 4.96 NTU) and 7 (5.58 ± 8.19 NTU). Nitrate levels (range: 5.95 to 28.12 mg L-1) and COD (range: 66.53 to 191.12 mg L-1) were higher than the recommended South African drinking water quality guidelines in most of the tanks. In the second experiments, the objective was to determine whether a modified hydrogen sulphide (H2S) test kit with an improved detection rate is an effective preliminary screening qualitative test that can be used for rainwater quality monitoring. The hydrogen sulphide method is a low-cost microbiological field-based test which can be used in areas where water testing facilities are limited. Harvested rainwater samples were collected from various tanks in the Eastern Cape and tested for contaminants of faecal origin using the modified hydrogen sulphide test kit, Colilert-18/Quanti-tray®/2000 and membrane filtration technique. Faecal coliforms were measured using membrane filtration, E. coli was measured using Colilert and correspondence rates were calculated with results of the improved hydrogen sulphide test kit. E. coli results ranged from <1 – >2419.6 MPN/100 mL while the faecal coliforms ranged from 0 – >300 CFU/mL. The agreement rate with hydrogen sulphide test and membrane filtration was 88% while the agreement rate for the Colilert and hydrogen sulphide test was 76%. The third experiments investigated the prevalence of pathogenic E. coli strains and their antimicrobial resistance patterns in HRW tanks in the Eastern Cape, South Africa. E. coli isolates obtained in the first experiments were further screened for their virulence potentials using polymerase chain reaction (PCR) and subsequently tested for antibiotic resistance using the disc-diffusion method against 11 antibiotics. The pathotype most detected was the neonatal meningitis E. coli (NMEC) (ibeA 28%) while pathotype enteroaggregative E. coli (EAEC) was not detected. The highest resistance of the E. coli isolates was observed against Cephalothin (76%). All tested pathotypes were susceptible to Gentamicin, and 52% demonstrated multiple-antibiotic resistance (MAR). The fourth experiments shed light on the occurrence of Legionella, zoonotic and fungal pathogens in the rainwater harvesting systems (RWHS) situated in different regions of South Africa. Rainwater samples were collected in urban and semi-urban areas from tanks situated in various areas in South Africa (Johannesburg, Pretoria and Grahamstown). Pathogenic organisms investigated were Salmonella, Shigella, Vibrio cholerae, Legionella and fungal isolates. Pure isolates were obtained and screened using PCR. Results revealed the presence of pathogenic bacteria and fungi in all the tested RWHS. In Grahamstown the most detected pathogen was Salmonella (73%) while Vibrio Cholerae was not detected. All the tested pathogens were present from the RWHS situated in Pretoria. Shigella was not detected from the RWHS in Johannesburg while others were detected. Identification of fungal isolates from HRW showed the presence of pathogenic fungi such as Aspergillus fumigatus, Cryptococcus laurentii, Aureobasidium pullulans and Mucor circinelloides. The last experiments, focussed on exploring a suitable treatment method for HRW where a nano compound quaternary imidazolium modified montmorillonite (MMT) was used as a potential household rainwater treatment option. Harvested rainwater samples were collected from the RWHS situated at the Council for Scientific and Industrial Research (CSIR), Pretoria South Africa. River and borehole water samples were included in the study to check the efficiency of the treatment method on various water sources. River water samples were collected from Olifants River, Witbank, South Africa while borehole water was collected from a privately-owned borehole in Pretoria. For inoculation studies, all the water sources were sterilised in batches of 1 and 2 L and inoculated with approximately 107 CFU/mL of overnight E. coli. Approximately 200 mg of the quaternary imidazolium modified MMT was added to the inoculated water and samples collected immediately after inoculation (time 0) and thereafter every hour for 5 hrs. The analyses were further conducted using unsterilised water samples (total bacterial count) and 500 mg of the treatment material. Complete inactivation of E. coli in sterilised HRW was achieved in 2 hrs for the 2 L water samples and 3 hrs for the 1 L water samples. Sterilised river water achieved complete E. coli inactivation in 4 hrs for the 1 L and 5 hrs for the 2 L samples while borehole water samples achieved complete E. coli inactivation in 5 hrs (2 L) and 6 hrs for the 1 L samples. In the unsterilised water sources (total bacteria), complete bacterial inactivation was observed in 5 hrs for both the 1 and 2 L harvested rainwater samples, 6 hrs in river water samples (both 1 and 2 L) and 8 hrs for borehole water samples (1 and 2 L). The results suggest that the treatment option was more efficient in harvested rainwater (required less time for bacterial inactivation compared to river and borehole water). The results of the current study are of public health concern since the use of untreated HRW for potable purposes may pose a risk of transmission of pathogenic and antimicrobial-resistant E. coli and other pathogenic organisms such as Salmonella, Shigella and Vibrio cholerae. It is therefore recommended that in cases where the tested harvested rainwater is used for potable purposes, simple treatment methods such as boiling and SODIS be applied so the harvested rainwater is fit for human consumption.
- Full Text: false
- Authors: Malema, Mokaba Shirley
- Date: 2020
- Language: English
- Type: thesis , text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/110218 , vital:33249 , https://dx.doi.org/10.21504/10962/110218
- Description: Thesis (PhD)--Rhodes University, Faculty of Science, Chemistry, 2020. , In most developing countries, people from rural and peri-urban settlements depend on harvested rainwater (HRW) as an alternative water source for drinking and other household purposes. Despite this reliance, there is little monitoring of the microbial quality of HRW in these areas. The most important issue in relation to using untreated harvested rainwater for drinking and other domestic purposes is the potential public health risks associated with microbial pathogens. Unlike chemical contamination, microbial contamination my lead to disease occurring rapidly, hence the need for frequent monitoring. Thus, the current study investigated the microbial quality of various domestic rainwater harvesting systems and the suitability of a nano based treatment method. The first experiments involved determining the microbial (Escherichia coli) and physicochemical quality (pH, turbidity, nitrate and chemical oxygen demand (COD)) of HRW in the Eastern Cape Province, South Africa. Samples were collected from 11 tanks situated at the Rhodes University, Kenton-on-sea (coastal) and in homes in the Grahamstown area on a weekly basis between June and September 2016. The Colilert-18®/Quanti-tray® 2000 system was used for enumeration of E. coli while physicochemical parameters were measured using commercial kits. Results showed that all samples were contaminated with varying concentrations of E. coli ranging from 7 to 1055 MPN/100 mL. Physicochemical analysis revealed that pH ranged from 5.6 to 7.6 and Turbidity values obtained for all tanks were below 5 NTU except for tank 4 (5.12 ± 4.96 NTU) and 7 (5.58 ± 8.19 NTU). Nitrate levels (range: 5.95 to 28.12 mg L-1) and COD (range: 66.53 to 191.12 mg L-1) were higher than the recommended South African drinking water quality guidelines in most of the tanks. In the second experiments, the objective was to determine whether a modified hydrogen sulphide (H2S) test kit with an improved detection rate is an effective preliminary screening qualitative test that can be used for rainwater quality monitoring. The hydrogen sulphide method is a low-cost microbiological field-based test which can be used in areas where water testing facilities are limited. Harvested rainwater samples were collected from various tanks in the Eastern Cape and tested for contaminants of faecal origin using the modified hydrogen sulphide test kit, Colilert-18/Quanti-tray®/2000 and membrane filtration technique. Faecal coliforms were measured using membrane filtration, E. coli was measured using Colilert and correspondence rates were calculated with results of the improved hydrogen sulphide test kit. E. coli results ranged from <1 – >2419.6 MPN/100 mL while the faecal coliforms ranged from 0 – >300 CFU/mL. The agreement rate with hydrogen sulphide test and membrane filtration was 88% while the agreement rate for the Colilert and hydrogen sulphide test was 76%. The third experiments investigated the prevalence of pathogenic E. coli strains and their antimicrobial resistance patterns in HRW tanks in the Eastern Cape, South Africa. E. coli isolates obtained in the first experiments were further screened for their virulence potentials using polymerase chain reaction (PCR) and subsequently tested for antibiotic resistance using the disc-diffusion method against 11 antibiotics. The pathotype most detected was the neonatal meningitis E. coli (NMEC) (ibeA 28%) while pathotype enteroaggregative E. coli (EAEC) was not detected. The highest resistance of the E. coli isolates was observed against Cephalothin (76%). All tested pathotypes were susceptible to Gentamicin, and 52% demonstrated multiple-antibiotic resistance (MAR). The fourth experiments shed light on the occurrence of Legionella, zoonotic and fungal pathogens in the rainwater harvesting systems (RWHS) situated in different regions of South Africa. Rainwater samples were collected in urban and semi-urban areas from tanks situated in various areas in South Africa (Johannesburg, Pretoria and Grahamstown). Pathogenic organisms investigated were Salmonella, Shigella, Vibrio cholerae, Legionella and fungal isolates. Pure isolates were obtained and screened using PCR. Results revealed the presence of pathogenic bacteria and fungi in all the tested RWHS. In Grahamstown the most detected pathogen was Salmonella (73%) while Vibrio Cholerae was not detected. All the tested pathogens were present from the RWHS situated in Pretoria. Shigella was not detected from the RWHS in Johannesburg while others were detected. Identification of fungal isolates from HRW showed the presence of pathogenic fungi such as Aspergillus fumigatus, Cryptococcus laurentii, Aureobasidium pullulans and Mucor circinelloides. The last experiments, focussed on exploring a suitable treatment method for HRW where a nano compound quaternary imidazolium modified montmorillonite (MMT) was used as a potential household rainwater treatment option. Harvested rainwater samples were collected from the RWHS situated at the Council for Scientific and Industrial Research (CSIR), Pretoria South Africa. River and borehole water samples were included in the study to check the efficiency of the treatment method on various water sources. River water samples were collected from Olifants River, Witbank, South Africa while borehole water was collected from a privately-owned borehole in Pretoria. For inoculation studies, all the water sources were sterilised in batches of 1 and 2 L and inoculated with approximately 107 CFU/mL of overnight E. coli. Approximately 200 mg of the quaternary imidazolium modified MMT was added to the inoculated water and samples collected immediately after inoculation (time 0) and thereafter every hour for 5 hrs. The analyses were further conducted using unsterilised water samples (total bacterial count) and 500 mg of the treatment material. Complete inactivation of E. coli in sterilised HRW was achieved in 2 hrs for the 2 L water samples and 3 hrs for the 1 L water samples. Sterilised river water achieved complete E. coli inactivation in 4 hrs for the 1 L and 5 hrs for the 2 L samples while borehole water samples achieved complete E. coli inactivation in 5 hrs (2 L) and 6 hrs for the 1 L samples. In the unsterilised water sources (total bacteria), complete bacterial inactivation was observed in 5 hrs for both the 1 and 2 L harvested rainwater samples, 6 hrs in river water samples (both 1 and 2 L) and 8 hrs for borehole water samples (1 and 2 L). The results suggest that the treatment option was more efficient in harvested rainwater (required less time for bacterial inactivation compared to river and borehole water). The results of the current study are of public health concern since the use of untreated HRW for potable purposes may pose a risk of transmission of pathogenic and antimicrobial-resistant E. coli and other pathogenic organisms such as Salmonella, Shigella and Vibrio cholerae. It is therefore recommended that in cases where the tested harvested rainwater is used for potable purposes, simple treatment methods such as boiling and SODIS be applied so the harvested rainwater is fit for human consumption.
- Full Text: false
Attentive amelioration: developing and evaluating an applied mindfulness programme for psychologists
- Authors: McGarvie, Susan
- Date: 2020
- Subjects: Attentive Amelioration Programme , Mindfulness (Psychology) , Psychotherapy -- Practice , Counseling -- Practice , Medical professionals -- Mental health
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/166186 , vital:41336
- Description: It is readily accepted that healthcare in many third world countries is in crisis, but interestingly, even in wealthy first world countries, many healthcare systems are stretched to their limits, as fewer people choose to follow a career in healthcare and more staff members struggle under the pressures of an overextended system (Krasner, et al., 2009). Ways to improve healthcare practitioner wellbeing is thus a relevant and widely investigated topic (McCann et al., 2013), which has, until recently, been aimed at reducing the negative symptoms associated with poor wellbeing, such as stress and burnout. More recently, there has been burgeoning interest in the effects and potential benefits of mindfulness practice to wellbeing, especially in developed English-speaking countries like the UK, Canada, USA, Australia, as well as in Europe. The aim of this study was to contribute to this body of literature by proposing a more personalised and person-centred means to support and improve wellbeing. It was guided by an overarching research question, about the benefits of a mindfulness-based wellness course for practicing psychologists. This study is a mixed-methods narrative inquiry which employs both Action Research (AR) and Programme Evaluation methods. It involved the design, implementation and evaluation of a mindful-wellness programme, subsequently named the Attentive Amelioration programme. Ten participants were purposively recruited and enrolled in the programme, which ran over eight weeks and included coaching and blended learning facilitation methods, including: an introductory workshop (with a pedagogical mix of lecture, group discussion, practical activities, learners manual and YouTube clips), individual and group coaching sessions, and an online learning programme. The findings suggest that psychologists do experience a great deal of stress and perceived levels of burnout are high, even if the scores on the pre- and post- intervention self-assessment scales do not entirely support this perception. This study found that participants were open to and engaged with mindfulness training and practice and sustained that practice for several months post-intervention. Finally, overall findings suggest that while the Attentive Amelioration programme was effective as a means to cultivate and develop mindfulness, self-compassion and overall wellbeing in the short-term, further investigation is required to determine the sustainability of the effects over the long-term. The findings of this study support the overall aims of the study in that it has found that the participating psychologists found the Attentive Amelioration programme to be beneficial, supportive and even therapeutic. By contributing to and supporting findings of existing research, that suggest that a mindfulness-based coaching programme would be beneficial to psychologist wellbeing and therapeutic proficiency, it serves to advocate for mindfulness as a means to improve and sustain psychologist wellbeing..
- Full Text:
Attentive amelioration: developing and evaluating an applied mindfulness programme for psychologists
- Authors: McGarvie, Susan
- Date: 2020
- Subjects: Attentive Amelioration Programme , Mindfulness (Psychology) , Psychotherapy -- Practice , Counseling -- Practice , Medical professionals -- Mental health
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/166186 , vital:41336
- Description: It is readily accepted that healthcare in many third world countries is in crisis, but interestingly, even in wealthy first world countries, many healthcare systems are stretched to their limits, as fewer people choose to follow a career in healthcare and more staff members struggle under the pressures of an overextended system (Krasner, et al., 2009). Ways to improve healthcare practitioner wellbeing is thus a relevant and widely investigated topic (McCann et al., 2013), which has, until recently, been aimed at reducing the negative symptoms associated with poor wellbeing, such as stress and burnout. More recently, there has been burgeoning interest in the effects and potential benefits of mindfulness practice to wellbeing, especially in developed English-speaking countries like the UK, Canada, USA, Australia, as well as in Europe. The aim of this study was to contribute to this body of literature by proposing a more personalised and person-centred means to support and improve wellbeing. It was guided by an overarching research question, about the benefits of a mindfulness-based wellness course for practicing psychologists. This study is a mixed-methods narrative inquiry which employs both Action Research (AR) and Programme Evaluation methods. It involved the design, implementation and evaluation of a mindful-wellness programme, subsequently named the Attentive Amelioration programme. Ten participants were purposively recruited and enrolled in the programme, which ran over eight weeks and included coaching and blended learning facilitation methods, including: an introductory workshop (with a pedagogical mix of lecture, group discussion, practical activities, learners manual and YouTube clips), individual and group coaching sessions, and an online learning programme. The findings suggest that psychologists do experience a great deal of stress and perceived levels of burnout are high, even if the scores on the pre- and post- intervention self-assessment scales do not entirely support this perception. This study found that participants were open to and engaged with mindfulness training and practice and sustained that practice for several months post-intervention. Finally, overall findings suggest that while the Attentive Amelioration programme was effective as a means to cultivate and develop mindfulness, self-compassion and overall wellbeing in the short-term, further investigation is required to determine the sustainability of the effects over the long-term. The findings of this study support the overall aims of the study in that it has found that the participating psychologists found the Attentive Amelioration programme to be beneficial, supportive and even therapeutic. By contributing to and supporting findings of existing research, that suggest that a mindfulness-based coaching programme would be beneficial to psychologist wellbeing and therapeutic proficiency, it serves to advocate for mindfulness as a means to improve and sustain psychologist wellbeing..
- Full Text:
Attitudinal difference surveys perpetuate harmful tropes: A comment on Nattrass
- Rosenberg, Eureta, Le Grange, Lesley
- Authors: Rosenberg, Eureta , Le Grange, Lesley
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/370129 , vital:66300 , xlink:href="https://doi.org/10.17159/sajs.2020/8469"
- Description: We reply to the article, ‘Why are black South African students less likely to consider studying biological sciences?’, authored by University of Cape Town (UCT) researcher Nicoli Nattrass1 and published in the South African Journal of Science on 27 May 2020. At the time of writing our reply the article had already received sharp criticism from the Black Academic Caucus at UCT and in a statement released on 5 June 2020, the UCT executive distanced itself from the content of the paper, inviting rigorous, respectful review of the published research. Nattrass’ article1 follows two papers published in 2019 by scholars associated with South African universities, both of which were widely denounced for the racist undertones of their content. The first article was authored by Stellenbosch University researchers who reported on low cognitive functioning of coloured women linked to education levels and lifestyles2 ; see comment by Le Grange3 . The second article was co-authored by an adjunct professor at UCT and examined the role of cognitive ability or intelligence on slave exports from Africa4 . These publications gave rise to a broader debate on enduring racism in science and the re-ascendency of race science internationally. In this reply, we focus on the methodology of attitudinal survey used for the study reported by Nattrass (and by many other scientists). There are two lines of argument that we weave together: the quality of the research as reported, and problems inherent to comparative attitudinal survey research (regardless of how well it is executed). It should be noted that the Black Academic Caucus at UCT has also critiqued the research design, identifying many of the points we make here, and they have additionally included a discourse analysis of the paper (circulated via e-mail). To demonstrate how problematic a survey design can be, particularly when it is not rigorously executed, we share data and observations that counter the apparent findings of Nattrass’ study. We then argue that the publication of this research, in this manner, is detrimental to the biodiversity sector in which the tropes being perpetuated, can cause enormous harm. In the process we hope to encourage scientists to be more reflexive about their methodology, and we encourage the South African Journal of Science to publish works that are worthy of the young people of this country - research in which they can recognise themselves, rather than being forced to look at reductionist portrayals, legitimised under the banner of science.
- Full Text:
- Authors: Rosenberg, Eureta , Le Grange, Lesley
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/370129 , vital:66300 , xlink:href="https://doi.org/10.17159/sajs.2020/8469"
- Description: We reply to the article, ‘Why are black South African students less likely to consider studying biological sciences?’, authored by University of Cape Town (UCT) researcher Nicoli Nattrass1 and published in the South African Journal of Science on 27 May 2020. At the time of writing our reply the article had already received sharp criticism from the Black Academic Caucus at UCT and in a statement released on 5 June 2020, the UCT executive distanced itself from the content of the paper, inviting rigorous, respectful review of the published research. Nattrass’ article1 follows two papers published in 2019 by scholars associated with South African universities, both of which were widely denounced for the racist undertones of their content. The first article was authored by Stellenbosch University researchers who reported on low cognitive functioning of coloured women linked to education levels and lifestyles2 ; see comment by Le Grange3 . The second article was co-authored by an adjunct professor at UCT and examined the role of cognitive ability or intelligence on slave exports from Africa4 . These publications gave rise to a broader debate on enduring racism in science and the re-ascendency of race science internationally. In this reply, we focus on the methodology of attitudinal survey used for the study reported by Nattrass (and by many other scientists). There are two lines of argument that we weave together: the quality of the research as reported, and problems inherent to comparative attitudinal survey research (regardless of how well it is executed). It should be noted that the Black Academic Caucus at UCT has also critiqued the research design, identifying many of the points we make here, and they have additionally included a discourse analysis of the paper (circulated via e-mail). To demonstrate how problematic a survey design can be, particularly when it is not rigorously executed, we share data and observations that counter the apparent findings of Nattrass’ study. We then argue that the publication of this research, in this manner, is detrimental to the biodiversity sector in which the tropes being perpetuated, can cause enormous harm. In the process we hope to encourage scientists to be more reflexive about their methodology, and we encourage the South African Journal of Science to publish works that are worthy of the young people of this country - research in which they can recognise themselves, rather than being forced to look at reductionist portrayals, legitimised under the banner of science.
- Full Text:
Azadipyrromethenes for applications in photodynamic antimicrobial chemotherapy, photodynamic therapy and optical limiting
- Authors: Dubazana, Nadine
- Date: 2020
- Subjects: Dyes and dyeing -- Chemistry , Photochemotherapy , Cancer -- Photochemotherapy , Anti-infective agents , Staphylococcus aureus , Nonlinear optics , Azadipyrromethenes , BODIPY
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/166150 , vital:41333
- Description: Azadipyrromethenes, azaBODIPYs and zinc azadipyrromethene complexes were prepared and characterised to examine the effect on their photophysical properties of incorporating phenyl groups at the 1,3,5,7-positions with electron-donating and withdrawing groups at the para-positions. To enhance their ability to generate singlet oxygen, appropriate structural modifications were made through the addition of a Zn(II) ion or halogenation at the 2,6 positions. In vitro photodynamic therapy (PDT) studies targeting MCF-7 human breast cancer cells were carried out. To evaluate and understand the effectiveness of the dyes as photosensitisers, cellular uptake, phototoxicity and the half-maximal inhibitory concentration (IC50) values were analysed. Photodynamic antimicrobial chemotherapy (PACT) studies were also carried out to study the effectiveness of the dyes against Staphylococcus aureus (S. aureus). Dyes with donor-π-acceptor (D-π-A) properties were synthesised and tested against the second harmonic of the Nd:YAG laser in optical limiting (OL) studies. The second-order hyperpolarisability, third-order susceptibility and nonlinear absorption coefficient values were determined. The results suggest that 1,3,5,7-azaBODIPY dyes may be less suitable for use in this context than analogous D-π-A 3,5-distyrylBODIPY dyes. Molecular modelling was carried out to identify the structure-property relationships of the synthesised dyes by analysing trends in the energies of the frontier molecular orbitals (MOs) and spectroscopic properties.
- Full Text:
- Authors: Dubazana, Nadine
- Date: 2020
- Subjects: Dyes and dyeing -- Chemistry , Photochemotherapy , Cancer -- Photochemotherapy , Anti-infective agents , Staphylococcus aureus , Nonlinear optics , Azadipyrromethenes , BODIPY
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/166150 , vital:41333
- Description: Azadipyrromethenes, azaBODIPYs and zinc azadipyrromethene complexes were prepared and characterised to examine the effect on their photophysical properties of incorporating phenyl groups at the 1,3,5,7-positions with electron-donating and withdrawing groups at the para-positions. To enhance their ability to generate singlet oxygen, appropriate structural modifications were made through the addition of a Zn(II) ion or halogenation at the 2,6 positions. In vitro photodynamic therapy (PDT) studies targeting MCF-7 human breast cancer cells were carried out. To evaluate and understand the effectiveness of the dyes as photosensitisers, cellular uptake, phototoxicity and the half-maximal inhibitory concentration (IC50) values were analysed. Photodynamic antimicrobial chemotherapy (PACT) studies were also carried out to study the effectiveness of the dyes against Staphylococcus aureus (S. aureus). Dyes with donor-π-acceptor (D-π-A) properties were synthesised and tested against the second harmonic of the Nd:YAG laser in optical limiting (OL) studies. The second-order hyperpolarisability, third-order susceptibility and nonlinear absorption coefficient values were determined. The results suggest that 1,3,5,7-azaBODIPY dyes may be less suitable for use in this context than analogous D-π-A 3,5-distyrylBODIPY dyes. Molecular modelling was carried out to identify the structure-property relationships of the synthesised dyes by analysing trends in the energies of the frontier molecular orbitals (MOs) and spectroscopic properties.
- Full Text:
Bacterial degradation of coal discard and geologically weathered coal:
- Olawale, Jacob T, Edeki, Oghenekume G, Cowan, Keith A
- Authors: Olawale, Jacob T , Edeki, Oghenekume G , Cowan, Keith A
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/178694 , vital:40097 , https://doi.org/10.1007/s40789-020-00306-3
- Description: The biodegradation of coal discard is being intensively studied in South Africa in an effort to develop passive methods for the successful revegetation and rehabilitation of waste dumps, to mitigate pollution, and facilitate mine closure. Bacteria were isolated from slurries of coal tailings and diesel-contaminated soil, screened for coal biodegradation competence, characterized, and the colonization and degradation of coal discard and geologically weathered coal investigated using individual isolates and consortia. Ten novel coal-degrading bacterial strains were isolated and characterized, the gene sequences deposited with GenBank, and the (wild-type) strains deposited at Microbial Culture Collection, India.
- Full Text:
- Authors: Olawale, Jacob T , Edeki, Oghenekume G , Cowan, Keith A
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/178694 , vital:40097 , https://doi.org/10.1007/s40789-020-00306-3
- Description: The biodegradation of coal discard is being intensively studied in South Africa in an effort to develop passive methods for the successful revegetation and rehabilitation of waste dumps, to mitigate pollution, and facilitate mine closure. Bacteria were isolated from slurries of coal tailings and diesel-contaminated soil, screened for coal biodegradation competence, characterized, and the colonization and degradation of coal discard and geologically weathered coal investigated using individual isolates and consortia. Ten novel coal-degrading bacterial strains were isolated and characterized, the gene sequences deposited with GenBank, and the (wild-type) strains deposited at Microbial Culture Collection, India.
- Full Text:
Barriers to, and enablers of urban tree planting in low-cost housing areas: lessons from participatory learning processes in South Africa
- Authors: Gwedla, Nanamhla
- Date: 2020
- Subjects: Urban ecology (Sociology) -- South Africa -- Eastern Cape , Tree planting -- South Africa -- Eastern Cape , Trees in cities -- South Africa -- Eastern Cape , Urban forestry -- Law and legislation -- South Africa -- Eastern Cape , Low-income housing -- South Africa -- Eastern Cape , Cultural Historical Activity Theory (CHAT)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/167065 , vital:41434
- Description: The recent pronouncement of low-cost housing areas as sustainable human settlements came with an expectation for their development in line with Sustainable Development Goal (SDG) 11. Unfortunately, the historical legacy and various socio-economic, socio-political, and socio-cultural dynamics characteristic of these areas have proven it challenging for them to conform to all requirements of urban sustainability, as evidenced in part by the virtual lack of greenspaces and urban trees. Through a three-tier inquiry of urban tree planting in low-cost housing areas using inductive and deductive mixed methods approaches, the aim of this research was to investigate the barriers to, and enablers of, tree planting in low-cost housing areas, and explore participatory learning opportunities to address the challenges and enhance the enablers. In the first segment, a participatory urban forest governance conceptual framing lens was used to situate the various actors in the development of the low-cost housing area urban forest and the dynamics of their involvement in that regard. Inquiry focused on an overview of tree planting across South Africa using key informant interviews, observations and document analysis. Secondly, distribution of trees, and barriers and enablers of tree planting in selected low-cost housing areas in the Eastern Cape province using household surveys, observations, key informant interviews and document analysis were investigated. Finally, drawing on interventionist methodology and adoption of Cultural-Historical Activity Theory (CHAT), the third segment tested scenarios of tree planting in three different small towns through focus group discussions and knowledge-sharing awareness events about trees and tree planting using an activity systems approach. Findings from the first segment ascertain the national Department of Environment, Forestry and Fisheries (DEFF) as the custodian of forestry, and by extension urban forestry in South Africa. Municipalities are tasked with implementing greening plans and strategies for public space planting, while private businesses collaborate with entities to contribute to tree-planting as part of their Corporate Social Responsibility (CSR). Civil society, including residents and Non-Governmental Organizations (NGOs) also contribute, especially for private space planting. However, there are currently very few initiatives implemented in low-cost housing areas. An assessment of ten tree planting initiatives revealed that the DEFF is the most common partner and stakeholder, and normally provides resources such as funding and trees. Most programs reported having undertaken community engagement before and during the tree planting. The general outcomes of these initiatives were centred on the survival rate of trees, job creation, and development of parks and gardens. Findings from the first part of the second segment, conducted in eight small-medium sized towns in the Eastern Cape, revealed a general lack of trees along streets of both the newly developed and old low-cost housing areas. In the private spaces, most households (52 %) reported having at least one tree in their yard, with households in the older suburbs (60 %) reporting more trees than the newer ones (44 %). Most of these trees (66 %) had been planted as opposed to natural regeneration. Previous participation in urban tree planting programs was low, but 75 % of residents expressed willingness to participate in the future. Municipal officials from these towns corroborated that they do not host tree planting events or initiatives, which was demonstrated by the limited incorporation of urban forestry and urban greening in municipal Integrated Development Plans (IDP). In the second part of the second segment, three groupings of barriers and enablers into biophysical, social, and resources revealed that the most mentioned barriers for the private space were resource barriers. The most prominent barriers were limited space in people’s yards, insufficient funds for tree purchases and associated resources, the lack of equipment, and damage to planted trees. Private space enablers of tree planting suggested include the availability of funds, allocation of space, and changes in attitudes towards trees. According to residents, the most prominent barriers to public space planting include the perceived incompetence of municipalities, limited space on the street, insufficient funds for tree planting programmes, damage to trees in public spaces, crime associated with street trees, and politics. Additionally, municipal officials reported that their efforts to plant trees were hindered by lack of communication and coordination between municipal departments. Residents suggested that enlisting the skills of residents for tree planting, engaging in education and awareness initiatives about trees and tree planting, and changing attitudes towards trees could enable tree planting. Municipal officials opined that education and awareness, revisions to and implementation of Environmental Management Plans, and inter-departmental collaborations and partnerships could improve the prospects for public space planting. Drawing on key findings from the second segment, an intervention to involve communities in tree planting using a case study approach in three towns ensued. Here an activity systems analysis of participatory tree planting initiatives was used. Findings revealed an array of multi-activity systems with multiple and partially overlapping objectives related to tree planting. Residents demonstrated that, with support, they can champion urban tree planting for their suburbs. However, contradictions and tensions within and between various activity systems emerged, creating opportunities for the expansive transformation of an activity that was previously not a priority. This study highlights the current distribution of power and resources in the governance system of the urban forest, ascertains the spatial heterogeneity of urban trees in areas of a similar socio-economic context, and provides lessons for best-practice in tree planting that involves multiple actors. It provides in-depth insights into what constrains tree planting, and highlights the importance of residents in the governance system of urban forests and how this can constrain or advance tree planting. Further research in participatory urban forest governance for a developing country, low-income context could utilize an expansive learning platform as this will provide first-hand experiences into learning what is not yet there, and provide communities with the opportunities to explore and devise localized solutions to the lack of trees in their residential areas.
- Full Text:
- Authors: Gwedla, Nanamhla
- Date: 2020
- Subjects: Urban ecology (Sociology) -- South Africa -- Eastern Cape , Tree planting -- South Africa -- Eastern Cape , Trees in cities -- South Africa -- Eastern Cape , Urban forestry -- Law and legislation -- South Africa -- Eastern Cape , Low-income housing -- South Africa -- Eastern Cape , Cultural Historical Activity Theory (CHAT)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/167065 , vital:41434
- Description: The recent pronouncement of low-cost housing areas as sustainable human settlements came with an expectation for their development in line with Sustainable Development Goal (SDG) 11. Unfortunately, the historical legacy and various socio-economic, socio-political, and socio-cultural dynamics characteristic of these areas have proven it challenging for them to conform to all requirements of urban sustainability, as evidenced in part by the virtual lack of greenspaces and urban trees. Through a three-tier inquiry of urban tree planting in low-cost housing areas using inductive and deductive mixed methods approaches, the aim of this research was to investigate the barriers to, and enablers of, tree planting in low-cost housing areas, and explore participatory learning opportunities to address the challenges and enhance the enablers. In the first segment, a participatory urban forest governance conceptual framing lens was used to situate the various actors in the development of the low-cost housing area urban forest and the dynamics of their involvement in that regard. Inquiry focused on an overview of tree planting across South Africa using key informant interviews, observations and document analysis. Secondly, distribution of trees, and barriers and enablers of tree planting in selected low-cost housing areas in the Eastern Cape province using household surveys, observations, key informant interviews and document analysis were investigated. Finally, drawing on interventionist methodology and adoption of Cultural-Historical Activity Theory (CHAT), the third segment tested scenarios of tree planting in three different small towns through focus group discussions and knowledge-sharing awareness events about trees and tree planting using an activity systems approach. Findings from the first segment ascertain the national Department of Environment, Forestry and Fisheries (DEFF) as the custodian of forestry, and by extension urban forestry in South Africa. Municipalities are tasked with implementing greening plans and strategies for public space planting, while private businesses collaborate with entities to contribute to tree-planting as part of their Corporate Social Responsibility (CSR). Civil society, including residents and Non-Governmental Organizations (NGOs) also contribute, especially for private space planting. However, there are currently very few initiatives implemented in low-cost housing areas. An assessment of ten tree planting initiatives revealed that the DEFF is the most common partner and stakeholder, and normally provides resources such as funding and trees. Most programs reported having undertaken community engagement before and during the tree planting. The general outcomes of these initiatives were centred on the survival rate of trees, job creation, and development of parks and gardens. Findings from the first part of the second segment, conducted in eight small-medium sized towns in the Eastern Cape, revealed a general lack of trees along streets of both the newly developed and old low-cost housing areas. In the private spaces, most households (52 %) reported having at least one tree in their yard, with households in the older suburbs (60 %) reporting more trees than the newer ones (44 %). Most of these trees (66 %) had been planted as opposed to natural regeneration. Previous participation in urban tree planting programs was low, but 75 % of residents expressed willingness to participate in the future. Municipal officials from these towns corroborated that they do not host tree planting events or initiatives, which was demonstrated by the limited incorporation of urban forestry and urban greening in municipal Integrated Development Plans (IDP). In the second part of the second segment, three groupings of barriers and enablers into biophysical, social, and resources revealed that the most mentioned barriers for the private space were resource barriers. The most prominent barriers were limited space in people’s yards, insufficient funds for tree purchases and associated resources, the lack of equipment, and damage to planted trees. Private space enablers of tree planting suggested include the availability of funds, allocation of space, and changes in attitudes towards trees. According to residents, the most prominent barriers to public space planting include the perceived incompetence of municipalities, limited space on the street, insufficient funds for tree planting programmes, damage to trees in public spaces, crime associated with street trees, and politics. Additionally, municipal officials reported that their efforts to plant trees were hindered by lack of communication and coordination between municipal departments. Residents suggested that enlisting the skills of residents for tree planting, engaging in education and awareness initiatives about trees and tree planting, and changing attitudes towards trees could enable tree planting. Municipal officials opined that education and awareness, revisions to and implementation of Environmental Management Plans, and inter-departmental collaborations and partnerships could improve the prospects for public space planting. Drawing on key findings from the second segment, an intervention to involve communities in tree planting using a case study approach in three towns ensued. Here an activity systems analysis of participatory tree planting initiatives was used. Findings revealed an array of multi-activity systems with multiple and partially overlapping objectives related to tree planting. Residents demonstrated that, with support, they can champion urban tree planting for their suburbs. However, contradictions and tensions within and between various activity systems emerged, creating opportunities for the expansive transformation of an activity that was previously not a priority. This study highlights the current distribution of power and resources in the governance system of the urban forest, ascertains the spatial heterogeneity of urban trees in areas of a similar socio-economic context, and provides lessons for best-practice in tree planting that involves multiple actors. It provides in-depth insights into what constrains tree planting, and highlights the importance of residents in the governance system of urban forests and how this can constrain or advance tree planting. Further research in participatory urban forest governance for a developing country, low-income context could utilize an expansive learning platform as this will provide first-hand experiences into learning what is not yet there, and provide communities with the opportunities to explore and devise localized solutions to the lack of trees in their residential areas.
- Full Text:
Bat species richness and community composition along a mega-transect in the Okavango river basin:
- Weier, Sina M, Keith, Mark, Neef, Götz-Georg, Parker, Daniel M, Taylor, Peter J
- Authors: Weier, Sina M , Keith, Mark , Neef, Götz-Georg , Parker, Daniel M , Taylor, Peter J
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/149264 , vital:38820 , https://doi.org/10.3390/d12050188
- Description: The Okavango River Basin is a hotspot of bat diversity that requires urgent and adequate protection. To advise future conservation strategies, we investigated the relative importance of a range of potential environmental drivers of bat species richness and functional community composition in the Okavango River Basin. During annual canoe transects along the major rivers, originating in the central Angolan highlands, we recorded more than 25,000 bat echolocation calls from 2015 to 2018. We corrected for possible biases in sampling design and effort.
- Full Text:
- Authors: Weier, Sina M , Keith, Mark , Neef, Götz-Georg , Parker, Daniel M , Taylor, Peter J
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/149264 , vital:38820 , https://doi.org/10.3390/d12050188
- Description: The Okavango River Basin is a hotspot of bat diversity that requires urgent and adequate protection. To advise future conservation strategies, we investigated the relative importance of a range of potential environmental drivers of bat species richness and functional community composition in the Okavango River Basin. During annual canoe transects along the major rivers, originating in the central Angolan highlands, we recorded more than 25,000 bat echolocation calls from 2015 to 2018. We corrected for possible biases in sampling design and effort.
- Full Text:
Battle of the large carnivores: spatial partitioning in a small, enclosed reserve?
- Comley, Jessica, Joubert, Christoffel J, Mgqatsa, Nokubonga, Parker, Daniel M
- Authors: Comley, Jessica , Joubert, Christoffel J , Mgqatsa, Nokubonga , Parker, Daniel M
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/462581 , vital:76316 , xlink:href="https://hdl.handle.net/10520/EJC-2037326828"
- Description: Interspecific competition among terrestrial carnivores can have widespread impacts on community structure and can ultimately determine which species are able to coexist. Within the carnivore guild, coexistence can be achieved through either spatial, temporal or dietary partitioning. The most effective method of avoiding competition may be spatial partitioning, as it removes the potential for negative interactions. The ways in which large carnivore species utilize and partition space in small, enclosed reserves in South Africa is currently poorly understood. This knowledge gap weakens our understanding of which mechanisms structure large carnivore communities in these systems. Thus, our aim was to use Global Positioning System (GPS) collars to investigate the spatial dynamics of large carnivores [four lions (Panthera leo), three leopards (Panthera pardus) and three spotted hyaenas (Crocuta crocuta)] on a small, enclosed reserve (Selati Game Reserve). Regarding home ranges, lions had considerable overlap among themselves (especially the females), leopards had minimal overlap, while spotted hyaenas had no home range overlap. Although we found no evidence for spatial partitioning amongst the collared large carnivores, differences in the habitat use patterns of the three large carnivore species is evident. The high prey abundance of Selati, carnivore predation strategies, behavioural adaptations and ecological separation could be facilitating the coexistence of lions, spotted hyaenas and leopards in Selati. We encourage future research to be aimed at investigating the interactions of multiple sympatric carnivores in an attempt to bridge the knowledge gap on which mechanisms structure carnivore communities.
- Full Text:
- Authors: Comley, Jessica , Joubert, Christoffel J , Mgqatsa, Nokubonga , Parker, Daniel M
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/462581 , vital:76316 , xlink:href="https://hdl.handle.net/10520/EJC-2037326828"
- Description: Interspecific competition among terrestrial carnivores can have widespread impacts on community structure and can ultimately determine which species are able to coexist. Within the carnivore guild, coexistence can be achieved through either spatial, temporal or dietary partitioning. The most effective method of avoiding competition may be spatial partitioning, as it removes the potential for negative interactions. The ways in which large carnivore species utilize and partition space in small, enclosed reserves in South Africa is currently poorly understood. This knowledge gap weakens our understanding of which mechanisms structure large carnivore communities in these systems. Thus, our aim was to use Global Positioning System (GPS) collars to investigate the spatial dynamics of large carnivores [four lions (Panthera leo), three leopards (Panthera pardus) and three spotted hyaenas (Crocuta crocuta)] on a small, enclosed reserve (Selati Game Reserve). Regarding home ranges, lions had considerable overlap among themselves (especially the females), leopards had minimal overlap, while spotted hyaenas had no home range overlap. Although we found no evidence for spatial partitioning amongst the collared large carnivores, differences in the habitat use patterns of the three large carnivore species is evident. The high prey abundance of Selati, carnivore predation strategies, behavioural adaptations and ecological separation could be facilitating the coexistence of lions, spotted hyaenas and leopards in Selati. We encourage future research to be aimed at investigating the interactions of multiple sympatric carnivores in an attempt to bridge the knowledge gap on which mechanisms structure carnivore communities.
- Full Text:
Bayesian accelerated life tests for the Weibull distribution under non-informative priors
- Authors: Mostert, Philip
- Date: 2020
- Subjects: Accelerated life testing -- Statistical methods , Accelerated life testing -- Mathematical models , Failure time data analysis , Bayesian statistical decision theory , Monte Carlo method , Weibull distribution
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/172181 , vital:42173
- Description: In a competitive world where products are designed to last for long periods of time, obtaining time-to-failure data is both difficult and costly. Hence for products with high reliability, accelerated life testing is required to obtain relevant life-data quickly. This is done by placing the products under higher-than-use stress levels, thereby causing the products to fail prematurely. Part of the analysis of accelerated life-data requires a life distribution that describes the lifetime of a product at a given stress level and a life-stress relationship – which is some function that describes the way in which the life distribution changes across different stress levels. In this thesis it is assumed that the underlying life distribution is the wellknown Weibull distribution, with shape parameter constant over all stress levels and scale parameter as a log-linear function of stress. The primary objective of this thesis is to obtain estimates from Bayesian analysis, and this thesis considers five types of non-informative prior distributions: Jeffreys’ prior, reference priors, maximal data information prior, uniform prior and probability matching priors. Since the associated posterior distribution under all the derived non-informative priors are of an unknown form, the propriety of the posterior distributions is assessed to ensure admissible results. For comparison purposes, estimates obtained via the method of maximum likelihood are also considered. Finding these estimates requires solving non-linear equations, hence the Newton-Raphson algorithm is used to obtain estimates. A simulation study based on the time-to-failure of accelerated data is conducted to compare results between maximum likelihood and Bayesian estimates. As a result of the Bayesian posterior distributions being analytically intractable, two methods to obtain Bayesian estimates are considered: Markov chain Monte Carlo methods and Lindley’s approximation technique. In the simulation study the posterior means and the root mean squared error values of the estimates under the symmetric squared error loss function and the two asymmetric loss functions: the LINEX loss function and general entropy loss function, are considered. Furthermore the coverage rates for the Bayesian Markov chain Monte Carlo and maximum likelihood estimates are found, and are compared by their average interval lengths. A case study using a dataset based on accelerated time-to-failure of an insulating fluid is considered. The fit of these data for the Weibull distribution is studied and is compared to that of other popular life distributions. A full simulation study is conducted to illustrate convergence of the proper posterior distributions. Both maximum likelihood and Bayesian estimates are found for these data. The deviance information criterion is used to compare Bayesian estimates between the prior distributions. The case study is concluded by finding reliability estimates of the data at use-stress levels.
- Full Text:
- Authors: Mostert, Philip
- Date: 2020
- Subjects: Accelerated life testing -- Statistical methods , Accelerated life testing -- Mathematical models , Failure time data analysis , Bayesian statistical decision theory , Monte Carlo method , Weibull distribution
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/172181 , vital:42173
- Description: In a competitive world where products are designed to last for long periods of time, obtaining time-to-failure data is both difficult and costly. Hence for products with high reliability, accelerated life testing is required to obtain relevant life-data quickly. This is done by placing the products under higher-than-use stress levels, thereby causing the products to fail prematurely. Part of the analysis of accelerated life-data requires a life distribution that describes the lifetime of a product at a given stress level and a life-stress relationship – which is some function that describes the way in which the life distribution changes across different stress levels. In this thesis it is assumed that the underlying life distribution is the wellknown Weibull distribution, with shape parameter constant over all stress levels and scale parameter as a log-linear function of stress. The primary objective of this thesis is to obtain estimates from Bayesian analysis, and this thesis considers five types of non-informative prior distributions: Jeffreys’ prior, reference priors, maximal data information prior, uniform prior and probability matching priors. Since the associated posterior distribution under all the derived non-informative priors are of an unknown form, the propriety of the posterior distributions is assessed to ensure admissible results. For comparison purposes, estimates obtained via the method of maximum likelihood are also considered. Finding these estimates requires solving non-linear equations, hence the Newton-Raphson algorithm is used to obtain estimates. A simulation study based on the time-to-failure of accelerated data is conducted to compare results between maximum likelihood and Bayesian estimates. As a result of the Bayesian posterior distributions being analytically intractable, two methods to obtain Bayesian estimates are considered: Markov chain Monte Carlo methods and Lindley’s approximation technique. In the simulation study the posterior means and the root mean squared error values of the estimates under the symmetric squared error loss function and the two asymmetric loss functions: the LINEX loss function and general entropy loss function, are considered. Furthermore the coverage rates for the Bayesian Markov chain Monte Carlo and maximum likelihood estimates are found, and are compared by their average interval lengths. A case study using a dataset based on accelerated time-to-failure of an insulating fluid is considered. The fit of these data for the Weibull distribution is studied and is compared to that of other popular life distributions. A full simulation study is conducted to illustrate convergence of the proper posterior distributions. Both maximum likelihood and Bayesian estimates are found for these data. The deviance information criterion is used to compare Bayesian estimates between the prior distributions. The case study is concluded by finding reliability estimates of the data at use-stress levels.
- Full Text:
BEd foundation phase fourth year student teachers’ self-efficacy beliefs towards teaching mathematics and the self-reported factors that influence these self-efficacy beliefs
- Authors: Harrison, Chloe
- Date: 2020
- Subjects: Mathematics -- Study and teaching (Elementary) -- South Africa , Mathematics teachers -- Training of -- South Africa , Educational evaluation -- South Africa , Student teachers -- Training of -- South Africa , Student teachers -- Rating of -- South Africa , Social cognitive theory , Self-efficacy
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/147004 , vital:38584
- Description: The underperformance of mathematics teaching and learning is a pressing concern in South Africa. Many foundation phase in-service teachers show inadequate mathematics content knowledge which creates barriers to their learners acquiring adequate mathematics skills. Teacher training programmes offer a key opportunity to improve the instructional practices of teachers at foundation phase level. In order to improve the teaching skills of in-service teachers, one focus must be on teacher training programmes. Unfortunately, there are many foundation phase student teachers who are leaving the profession within the first few years of teaching reportedly due to low levels of motivation. This research investigates the self-efficacy beliefs of pre-service student teachers. It also focuses on foundation phase student teachers as they experience significant challenges to their self-efficacy beliefs in mathematics and mathematics teaching. Self-efficacy is the key theory of the study. It stems from Bandura’s social cognitive theory and is an individual’s judgments about their capabilities, skills and perceived performance. This qualitative research adopts an interpretivist approach which seeks to identify Bed foundation phase fourth year student teachers’ self-efficacy beliefs towards teaching mathematics and the self-reported factors influencing such beliefs. This research found that BEd foundation phase fourth year student teachers have low self-efficacy beliefs towards teaching mathematics. The purpose of this research is to raise awareness of the BEd student teachers’ low self-efficacy beliefs towards teaching mathematics. The results from this research will provide a platform for future intervention research, as well as potentially influencing student teacher training programmes.
- Full Text:
- Authors: Harrison, Chloe
- Date: 2020
- Subjects: Mathematics -- Study and teaching (Elementary) -- South Africa , Mathematics teachers -- Training of -- South Africa , Educational evaluation -- South Africa , Student teachers -- Training of -- South Africa , Student teachers -- Rating of -- South Africa , Social cognitive theory , Self-efficacy
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/147004 , vital:38584
- Description: The underperformance of mathematics teaching and learning is a pressing concern in South Africa. Many foundation phase in-service teachers show inadequate mathematics content knowledge which creates barriers to their learners acquiring adequate mathematics skills. Teacher training programmes offer a key opportunity to improve the instructional practices of teachers at foundation phase level. In order to improve the teaching skills of in-service teachers, one focus must be on teacher training programmes. Unfortunately, there are many foundation phase student teachers who are leaving the profession within the first few years of teaching reportedly due to low levels of motivation. This research investigates the self-efficacy beliefs of pre-service student teachers. It also focuses on foundation phase student teachers as they experience significant challenges to their self-efficacy beliefs in mathematics and mathematics teaching. Self-efficacy is the key theory of the study. It stems from Bandura’s social cognitive theory and is an individual’s judgments about their capabilities, skills and perceived performance. This qualitative research adopts an interpretivist approach which seeks to identify Bed foundation phase fourth year student teachers’ self-efficacy beliefs towards teaching mathematics and the self-reported factors influencing such beliefs. This research found that BEd foundation phase fourth year student teachers have low self-efficacy beliefs towards teaching mathematics. The purpose of this research is to raise awareness of the BEd student teachers’ low self-efficacy beliefs towards teaching mathematics. The results from this research will provide a platform for future intervention research, as well as potentially influencing student teacher training programmes.
- Full Text:
Benthic diatom-based indices and isotopic biomonitoring of nitrogen pollution in a warm temperate Austral river system
- Dalu, Tatenda, Cuthbert, Ross N, Taylor, Jonathan C, Magoro, Mandla L, Weyl, Olaf L F, Froneman, P William, Wasserman, Ryan J
- Authors: Dalu, Tatenda , Cuthbert, Ross N , Taylor, Jonathan C , Magoro, Mandla L , Weyl, Olaf L F , Froneman, P William , Wasserman, Ryan J
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/466917 , vital:76798 , https://doi.org/10.1016/j.scitotenv.2020.142452
- Description: Rivers are impacted by pollutants from anthropogenic activities such as urbanisation and agricultural practices. Whilst point source pollution has been widely studied and in some cases remediated, non-point pollutant sources remain pervasive, particularly in developing countries that lack economic and human specialist capacity. Monitoring of pollution levels in many regions is additionally challenged by a lack of robust indicators for nitrogen inputs, however, diatom community indices and analysis of variation in microphytobenthos (MBP) stable isotope analysis variations have potential. The present study investigates variations and utilities in benthic diatom indices and MPB δ15N along different river sections (n = 31) of an austral river between two seasons (wet and dry), testing for relationships with key environmental variables (physical, water and sediment), in the context of N monitoring. One hundred and eighteen diatom taxa belonging to 36 genera were identified, with physical (water flow), water (nitrate, P and total dissolved solids) and sediment (B, Ca, Cr, Na, N, P, SOM, Pb and Zn) variables correlating to one or more of the 12 diatom indices presented. In particular, Biological Diatom Index, Biological Index of Water Quality, Central Economic Community, Index of Artois-Picardie Diatom (IDAP) and Sládeček's Index were strongly explained by sediment variables, whilst Descy's Pollution Index and Schiefele and Schreiner's Index were explained by water and physical variables.
- Full Text:
- Authors: Dalu, Tatenda , Cuthbert, Ross N , Taylor, Jonathan C , Magoro, Mandla L , Weyl, Olaf L F , Froneman, P William , Wasserman, Ryan J
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/466917 , vital:76798 , https://doi.org/10.1016/j.scitotenv.2020.142452
- Description: Rivers are impacted by pollutants from anthropogenic activities such as urbanisation and agricultural practices. Whilst point source pollution has been widely studied and in some cases remediated, non-point pollutant sources remain pervasive, particularly in developing countries that lack economic and human specialist capacity. Monitoring of pollution levels in many regions is additionally challenged by a lack of robust indicators for nitrogen inputs, however, diatom community indices and analysis of variation in microphytobenthos (MBP) stable isotope analysis variations have potential. The present study investigates variations and utilities in benthic diatom indices and MPB δ15N along different river sections (n = 31) of an austral river between two seasons (wet and dry), testing for relationships with key environmental variables (physical, water and sediment), in the context of N monitoring. One hundred and eighteen diatom taxa belonging to 36 genera were identified, with physical (water flow), water (nitrate, P and total dissolved solids) and sediment (B, Ca, Cr, Na, N, P, SOM, Pb and Zn) variables correlating to one or more of the 12 diatom indices presented. In particular, Biological Diatom Index, Biological Index of Water Quality, Central Economic Community, Index of Artois-Picardie Diatom (IDAP) and Sládeček's Index were strongly explained by sediment variables, whilst Descy's Pollution Index and Schiefele and Schreiner's Index were explained by water and physical variables.
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Between nationalism and transnationalism: entanglements of history, individual narrative, and memory in diaspora spaces in selected transnational fiction
- Authors: Bosman, Sean James
- Date: 2020
- Subjects: Literature and transnationalism , Gurnah, Abdulrazak, 1948- , Gurnah, Abdulrazak, 1948- -- By the sea , Gurnah, Abdulrazak, 1948- -- Gravel heart , Nguyen, Viet Thanh, 1971- , Nguyen, Viet Thanh, 1971- -- The sympathizer , Nguyen, Viet Thanh, 1971- -- The refugees , Urrea, Luis Alberto , Urrea, Luis Alberto -- The house of broken angels , Urrea, Luis Alberto -- The water museum
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/140932 , vital:37930
- Description: This thesis offers close readings and a comparative analysis of selected works by Abdulrazak Gurnah, Viet Thanh Nguyen, and Luis Alberto Urrea. The selected primary texts used are Gurnah’s By the Sea (2000) and Gravel Heart (2017), Nguyen’s The Sympathizer (2015) and The Refugees (2017), and Urrea’s The Water Museum (2015) and The House of Broken Angels (2018). Analyses are informed by a conceptual framework that draws on critical works by Avtar Brah, J. U. Jacobs, Sarah Nuttall, Homi K. Bhabha, Judith Butler, Stuart Hall, Paul Ricoeur, Viet Thanh Nguyen, and Christopher B. Patterson. These theories are deployed to analyse how the selected works engage with the entanglements of history, individual narratives, and memory in the diaspora spaces they articulate. The thesis argues that the selected works indicate an emerging subgenre within the broader category of transnational literature. This subgenre rejects disempowering interpolations of transnational identities. Instead, it prioritises ethical forms of memory. These acknowledge that transnational subjects share at least partial accountability for the precarity they experience in diaspora spaces. The selected literature limns how this may be accomplished by rejecting the label of victim. In so doing, the selected literature also suggests that the elevation of transnationals to full ethical agency would enable them to exercise power in their diaspora spaces. All three authorial projects studied here also give rise to uncomfortable juxtapositions that suggest a mounting fear that, as nationalisms become more pronounced in the UK and the USA, transnationals may have to re-experience conditions from which they have already fled. The thesis concludes by identifying four additional areas of confluence amongst the selected literature worthy of future study.
- Full Text:
- Authors: Bosman, Sean James
- Date: 2020
- Subjects: Literature and transnationalism , Gurnah, Abdulrazak, 1948- , Gurnah, Abdulrazak, 1948- -- By the sea , Gurnah, Abdulrazak, 1948- -- Gravel heart , Nguyen, Viet Thanh, 1971- , Nguyen, Viet Thanh, 1971- -- The sympathizer , Nguyen, Viet Thanh, 1971- -- The refugees , Urrea, Luis Alberto , Urrea, Luis Alberto -- The house of broken angels , Urrea, Luis Alberto -- The water museum
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/140932 , vital:37930
- Description: This thesis offers close readings and a comparative analysis of selected works by Abdulrazak Gurnah, Viet Thanh Nguyen, and Luis Alberto Urrea. The selected primary texts used are Gurnah’s By the Sea (2000) and Gravel Heart (2017), Nguyen’s The Sympathizer (2015) and The Refugees (2017), and Urrea’s The Water Museum (2015) and The House of Broken Angels (2018). Analyses are informed by a conceptual framework that draws on critical works by Avtar Brah, J. U. Jacobs, Sarah Nuttall, Homi K. Bhabha, Judith Butler, Stuart Hall, Paul Ricoeur, Viet Thanh Nguyen, and Christopher B. Patterson. These theories are deployed to analyse how the selected works engage with the entanglements of history, individual narratives, and memory in the diaspora spaces they articulate. The thesis argues that the selected works indicate an emerging subgenre within the broader category of transnational literature. This subgenre rejects disempowering interpolations of transnational identities. Instead, it prioritises ethical forms of memory. These acknowledge that transnational subjects share at least partial accountability for the precarity they experience in diaspora spaces. The selected literature limns how this may be accomplished by rejecting the label of victim. In so doing, the selected literature also suggests that the elevation of transnationals to full ethical agency would enable them to exercise power in their diaspora spaces. All three authorial projects studied here also give rise to uncomfortable juxtapositions that suggest a mounting fear that, as nationalisms become more pronounced in the UK and the USA, transnationals may have to re-experience conditions from which they have already fled. The thesis concludes by identifying four additional areas of confluence amongst the selected literature worthy of future study.
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Between past and future: memory and mourning in the stories of Okwiri Oduor and Ndinda Kioko
- Authors: Awuor, Nicholas Amol
- Date: 2020
- Subjects: Oduor, Okwiri -- Criticism and interpretation , Oduor, Okwiri -- The plea bargain , Oduor, Okwiri -- My father's head , Oduor, Okwiri -- Rag doll , Kioko, Ndinda -- Criticism and interpretation , Kioko, Ndinda -- Sometime Before Maulidi , Kioko, Ndinda -- Some Freedom Dreams , Authors, Kenyan -- Criticism and interpretation , Kenyan fiction (English) -- History and criticism , Kenyan literature (English) -- History and criticism
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/163168 , vital:41015
- Description: This study investigates the literary activities of two emerging female Kenyan writers, Claudette Okwiri Oduor and Jacqueline Ndinda Kioko, both of whom are award-winning authors. Oduor won the 2014 Caine Prize for African Writing while Kioko bagged the Wasafiri New Writing Fiction Award 2017. It examines specifically how the writers deal with memory and mourning in negotiating between the past and future. I explore how their fictional and non-fictional narratives assist individuals and groups to confront loss, reconstruct new identities, and renegotiate belonging amidst personal and social upheaval. The fictional narratives at the centre of this research are Oduor’s “The Plea Bargain” (2011), “My Father’s Head” (2013) and “Rag Doll” (2014), and Kioko’s “Sometime Before Maulidi” (2014) and “Some Freedom Dreams” (2017). The study explores the themes of mental illness, existential crisis, and fragmentation, and considers bereavement, queer relationships, cultural freedom, and social recognition. The research further considers the active participation of these two writers in Kenya’s contemporary literary-cultural conversations, which span different genres and various media platforms, including blogs, YouTube clips, online magazines, and social media networks in dialogue with other writers. I trace the significance of the literary-cultural link these authors have with their local, continental, and global counterparts in countries like Uganda, Nigeria, and South Africa. The link finds expression through their (in)direct association with some of the new online publishing outlets in Kenya like Jalada Africa, Enkare Review, and Kikwetu. More importantly, their shared participation in and association with such international awards and scholarships as the Commonwealth Short Story Prize, Kwani Trust Manuscript Project, and Miles Morland Foundation is integral in apprehending contemporary literary exchanges and multidirectional flows of publishing in Africa and beyond. I equally illustrate how mentorship of younger writers through local writers’ organisations and collectives like AMKA and Writivism help in the formation of an alternative canon other than the mainstream. The study affirms that the authors seem to transcend the boundaries of production and circulation by fluidly moving between electronic and non-electronic platforms, thus mimicking the memory production of remembering, repeating, and working through.
- Full Text:
- Authors: Awuor, Nicholas Amol
- Date: 2020
- Subjects: Oduor, Okwiri -- Criticism and interpretation , Oduor, Okwiri -- The plea bargain , Oduor, Okwiri -- My father's head , Oduor, Okwiri -- Rag doll , Kioko, Ndinda -- Criticism and interpretation , Kioko, Ndinda -- Sometime Before Maulidi , Kioko, Ndinda -- Some Freedom Dreams , Authors, Kenyan -- Criticism and interpretation , Kenyan fiction (English) -- History and criticism , Kenyan literature (English) -- History and criticism
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/163168 , vital:41015
- Description: This study investigates the literary activities of two emerging female Kenyan writers, Claudette Okwiri Oduor and Jacqueline Ndinda Kioko, both of whom are award-winning authors. Oduor won the 2014 Caine Prize for African Writing while Kioko bagged the Wasafiri New Writing Fiction Award 2017. It examines specifically how the writers deal with memory and mourning in negotiating between the past and future. I explore how their fictional and non-fictional narratives assist individuals and groups to confront loss, reconstruct new identities, and renegotiate belonging amidst personal and social upheaval. The fictional narratives at the centre of this research are Oduor’s “The Plea Bargain” (2011), “My Father’s Head” (2013) and “Rag Doll” (2014), and Kioko’s “Sometime Before Maulidi” (2014) and “Some Freedom Dreams” (2017). The study explores the themes of mental illness, existential crisis, and fragmentation, and considers bereavement, queer relationships, cultural freedom, and social recognition. The research further considers the active participation of these two writers in Kenya’s contemporary literary-cultural conversations, which span different genres and various media platforms, including blogs, YouTube clips, online magazines, and social media networks in dialogue with other writers. I trace the significance of the literary-cultural link these authors have with their local, continental, and global counterparts in countries like Uganda, Nigeria, and South Africa. The link finds expression through their (in)direct association with some of the new online publishing outlets in Kenya like Jalada Africa, Enkare Review, and Kikwetu. More importantly, their shared participation in and association with such international awards and scholarships as the Commonwealth Short Story Prize, Kwani Trust Manuscript Project, and Miles Morland Foundation is integral in apprehending contemporary literary exchanges and multidirectional flows of publishing in Africa and beyond. I equally illustrate how mentorship of younger writers through local writers’ organisations and collectives like AMKA and Writivism help in the formation of an alternative canon other than the mainstream. The study affirms that the authors seem to transcend the boundaries of production and circulation by fluidly moving between electronic and non-electronic platforms, thus mimicking the memory production of remembering, repeating, and working through.
- Full Text:
Between past and future: memory and mourning in the stories of Okwiri Oduor and Ndinda Kioko
- Authors: Awuor, Nicholas Amol
- Date: 2020
- Subjects: Women authors, Kenyan , Oduor, Okwiri -- The plea bargain , Oduor, Okwiri -- My father's head , Oduor, Okwiri -- Rag doll , Kioko, Ndinda -- Sometime before Maulidi , Kioko, Ndinda -- Some freedom dreams , Women and literature -- Africa , Bereavement -- Fiction , Culture in literature , Liberty in literature
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/161229 , vital:40608
- Description: This study investigates the literary activities of two emerging female Kenyan writers, Claudette Okwiri Oduor and Jacqueline Ndinda Kioko, both of whom are award-winning authors. Oduor won the 2014 Caine Prize for African Writing while Kioko bagged the Wasafiri New Writing Fiction Award 2017. It examines specifically how the writers deal with memory and mourning in negotiating between the past and future. I explore how their fictional and non-fictional narratives assist individuals and groups to confront loss, reconstruct new identities, and renegotiate belonging amidst personal and social upheaval. The fictional narratives at the centre of this research are Oduor’s “The Plea Bargain” (2011), “My Father’s Head” (2013) and “Rag Doll” (2014), and Kioko’s “Sometime Before Maulidi” (2014) and “Some Freedom Dreams” (2017). The study explores the themes of mental illness, existential crisis, and fragmentation, and considers bereavement, queer relationships, cultural freedom, and social recognition. The research further considers the active participation of these two writers in Kenya’s contemporary literary-cultural conversations, which span different genres and various media platforms, including blogs, YouTube clips, online magazines, and social media networks in dialogue with other writers. . I trace the significance of the literary-cultural link these authors have with their local, continental, and global counterparts in countries like Uganda, Nigeria, and South Africa. The link finds expression through their (in)direct association with some of the new online publishing outlets in Kenya like Jalada Africa, Enkare Review, and Kikwetu. More importantly, their shared participation in and association with such international awards and scholarships as the Commonwealth Short Story Prize, Kwani Trust Manuscript Project, and Miles Morland Foundation is integral in apprehending contemporary literary exchanges and multidirectional flows of publishing in Africa and beyond. I equally illustrate how mentorship of younger writers through local writers’ organisations and collectives like AMKA and Writivism help in the formation of an alternative canon other than the mainstream. The study affirms that the authors seem to transcend the boundaries of production and circulation by fluidly moving between electronic and non-electronic platforms, thus mimicking the memory production of remembering, repeating, and working through.
- Full Text:
- Authors: Awuor, Nicholas Amol
- Date: 2020
- Subjects: Women authors, Kenyan , Oduor, Okwiri -- The plea bargain , Oduor, Okwiri -- My father's head , Oduor, Okwiri -- Rag doll , Kioko, Ndinda -- Sometime before Maulidi , Kioko, Ndinda -- Some freedom dreams , Women and literature -- Africa , Bereavement -- Fiction , Culture in literature , Liberty in literature
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/161229 , vital:40608
- Description: This study investigates the literary activities of two emerging female Kenyan writers, Claudette Okwiri Oduor and Jacqueline Ndinda Kioko, both of whom are award-winning authors. Oduor won the 2014 Caine Prize for African Writing while Kioko bagged the Wasafiri New Writing Fiction Award 2017. It examines specifically how the writers deal with memory and mourning in negotiating between the past and future. I explore how their fictional and non-fictional narratives assist individuals and groups to confront loss, reconstruct new identities, and renegotiate belonging amidst personal and social upheaval. The fictional narratives at the centre of this research are Oduor’s “The Plea Bargain” (2011), “My Father’s Head” (2013) and “Rag Doll” (2014), and Kioko’s “Sometime Before Maulidi” (2014) and “Some Freedom Dreams” (2017). The study explores the themes of mental illness, existential crisis, and fragmentation, and considers bereavement, queer relationships, cultural freedom, and social recognition. The research further considers the active participation of these two writers in Kenya’s contemporary literary-cultural conversations, which span different genres and various media platforms, including blogs, YouTube clips, online magazines, and social media networks in dialogue with other writers. . I trace the significance of the literary-cultural link these authors have with their local, continental, and global counterparts in countries like Uganda, Nigeria, and South Africa. The link finds expression through their (in)direct association with some of the new online publishing outlets in Kenya like Jalada Africa, Enkare Review, and Kikwetu. More importantly, their shared participation in and association with such international awards and scholarships as the Commonwealth Short Story Prize, Kwani Trust Manuscript Project, and Miles Morland Foundation is integral in apprehending contemporary literary exchanges and multidirectional flows of publishing in Africa and beyond. I equally illustrate how mentorship of younger writers through local writers’ organisations and collectives like AMKA and Writivism help in the formation of an alternative canon other than the mainstream. The study affirms that the authors seem to transcend the boundaries of production and circulation by fluidly moving between electronic and non-electronic platforms, thus mimicking the memory production of remembering, repeating, and working through.
- Full Text:
Biocompatibility of biomaterials for nanoencapsulation: Current approaches
- Witika, Bwalya A, Makoni, Pedzisai A, Matafwali, Scott K, Chabalenge, Billy, Mwila, Chiluba, Kalungia, Aubrey C, Nkanga, Christian I, Bapolisi, Alain M, Walker, Roderick B
- Authors: Witika, Bwalya A , Makoni, Pedzisai A , Matafwali, Scott K , Chabalenge, Billy , Mwila, Chiluba , Kalungia, Aubrey C , Nkanga, Christian I , Bapolisi, Alain M , Walker, Roderick B
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/183289 , vital:43939 , xlink:href="https://doi.org/10.3390/nano10091649"
- Description: Nanoencapsulation is an approach to circumvent shortcomings such as reduced bioavailability, undesirable side effects, frequent dosing and unpleasant organoleptic properties of conventional drug delivery systems. The process of nanoencapsulation involves the use of biomaterials such as surfactants and/or polymers, often in combination with charge inducers and/or ligands for targeting. The biomaterials selected for nanoencapsulation processes must be as biocompatible as possible. The type(s) of biomaterials used for different nanoencapsulation approaches are highlighted and their use and applicability with regard to haemo- and, histocompatibility, cytotoxicity, genotoxicity and carcinogenesis are discussed.
- Full Text:
- Authors: Witika, Bwalya A , Makoni, Pedzisai A , Matafwali, Scott K , Chabalenge, Billy , Mwila, Chiluba , Kalungia, Aubrey C , Nkanga, Christian I , Bapolisi, Alain M , Walker, Roderick B
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/183289 , vital:43939 , xlink:href="https://doi.org/10.3390/nano10091649"
- Description: Nanoencapsulation is an approach to circumvent shortcomings such as reduced bioavailability, undesirable side effects, frequent dosing and unpleasant organoleptic properties of conventional drug delivery systems. The process of nanoencapsulation involves the use of biomaterials such as surfactants and/or polymers, often in combination with charge inducers and/or ligands for targeting. The biomaterials selected for nanoencapsulation processes must be as biocompatible as possible. The type(s) of biomaterials used for different nanoencapsulation approaches are highlighted and their use and applicability with regard to haemo- and, histocompatibility, cytotoxicity, genotoxicity and carcinogenesis are discussed.
- Full Text:
Biodiversity conservation and rural livelihoods across four nature reserves in the Eastern Cape Province, South Africa: Striving towards a balance between livelihoods and conservation
- Authors: Angwenyi, Daniel
- Date: 2020
- Subjects: National parks and reserves -- South Africa -- Eastern Cape , Nature conservation -- South Africa -- Eastern Cape , Biodiversity conservation -- South Africa -- Eastern Cape , Rural population -- South Africa -- Eastern Cape , Sustainable development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/138551 , vital:37649
- Description: The realisation that biodiversity is being lost at alarming rates, and that intact ecosystems are essential for ecological functioning and sustenance of human life, has led to biodiversity taking centre stage in national and international agencies’ environmental talks agendas. Protected areas are viable option to stem biodiversity loss. However, the establishment of protected areas might have negative impacts on communities living adjacent to them, leading to poor relations and frequent conflicts between these communities and the managers of protected areas. The Eastern Cape Province has twenty-one nature reserves and three national parks. Since the province is rural, the assumption was likelihood that households in the province depended on natural resources, specifically non-timber forest products for their day-to-day needs. Therefore, it was hypothesised that conserving natural resources, was likely to negatively impact on the livelihoods of most households adjacent to these areas, which in turn would influence their perceptions towards these resources and eventually the effectiveness of conservation efforts. This study aimed at examining the relationship between biodiversity conservation and rural livelihoods in the Eastern Cape Province, South Africa, focusing on four nature reserves – Tsolwana, Hluleka, Mkambati and Great Fish River. The objectives of the study were to: I I. Compare the vegetation productivity inside and outside, as well as land cover change in four nature reserves, as an indicator of conservation effectiveness. II II. Evaluate the relationship between biodiversity conservation and livelihoods in four nature reserves. III III. Evaluate how people’s expectations of nature reserves and perceptions towards nature reserve influence their support of conservation activities. Four hundred semi-structured questionnaires were administered to household heads of communities living at various distances from the four nature reserves, using a gradient design (based on distance). The motive of using distance was to assess whether livelihood status varied with distance from the nature reserves, since data on livelihood before the reserves’ establishment could not be obtained. Through a questionnaire survey, data on demographic information, livelihood assets, livelihood activities, livelihood strategies, livelihood trends, and impacts of the reserves on local communities were gathered. Focus group interviews were also conducted to complement the household surveys. A chi-square test was used to test if there was a relationship between distance from the reserves’ boundaries and local communities’ state of livelihoods. NVivo was used to analyse qualitative data Themes substantiated using literature. The study finds that the reserves did not have any impact on livelihood assets because most households in the study area did not directly depend on the resources found in the reserves. These households depended mostly on government grants and remittances from relatives working in other areas in the country. The reserves, however, supplied some goods and services to local communities, including meat, jobs, water, building materials, security from wild animals, education, skills development, and recreation. There were also a number of negative impacts associated with the reserves including resource use restrictions, harassment by reserves management, killing of domestic animals, and attacks on humans by wild animals escaping from the reserve. The majority (60%) of locals had substantive knowledge of the reserves’ role because of this awareness, 79% were supportive of reserves. However, there were mixed views by locals on the best way to manage these reserves. The most dominant view was that natural resources should be preserved for future generations, while meeting the current generation’s livelihood needs. Other lesser views included that the reserves’ management should involve locals in the management structures, either as active members or through consultation. Similarly, there were people feeling that the reserve is an obstacle to their livelihoods and should be closed and the land returned to the rightful owners. The vegetation productivity was better inside as compared to the outside the reserves. This activity also improved in the sixteen (16) years under assessment. This imply that the ecological functionality of the reserves is better than the surrounding areas and is improving with time. The research recommended that local communities could be an asset in conservation since most of them were in favour of the reserves. This, however, will need reserve managers to form workable partnerships with these communities, where the rights and responsibilities for both parties are defined. Besides these partnerships, lease agreements between local communities and reserves management to enhance benefits to the communities could encourage local communities to take pride in the natural resources within the reserves. This will ultimately becoming stewards to these resources. Development of tourism infrastructure such as curio shops and convenience stores to enhance livelihood opportunities could also help. For the local communities to be well represented it is important that the committees representing them in the various reserve matters be expanded and democratically elected. Where necessary, community awareness programmes on the importance of the reserves and the roles of local communities should be implemented.
- Full Text:
- Authors: Angwenyi, Daniel
- Date: 2020
- Subjects: National parks and reserves -- South Africa -- Eastern Cape , Nature conservation -- South Africa -- Eastern Cape , Biodiversity conservation -- South Africa -- Eastern Cape , Rural population -- South Africa -- Eastern Cape , Sustainable development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/138551 , vital:37649
- Description: The realisation that biodiversity is being lost at alarming rates, and that intact ecosystems are essential for ecological functioning and sustenance of human life, has led to biodiversity taking centre stage in national and international agencies’ environmental talks agendas. Protected areas are viable option to stem biodiversity loss. However, the establishment of protected areas might have negative impacts on communities living adjacent to them, leading to poor relations and frequent conflicts between these communities and the managers of protected areas. The Eastern Cape Province has twenty-one nature reserves and three national parks. Since the province is rural, the assumption was likelihood that households in the province depended on natural resources, specifically non-timber forest products for their day-to-day needs. Therefore, it was hypothesised that conserving natural resources, was likely to negatively impact on the livelihoods of most households adjacent to these areas, which in turn would influence their perceptions towards these resources and eventually the effectiveness of conservation efforts. This study aimed at examining the relationship between biodiversity conservation and rural livelihoods in the Eastern Cape Province, South Africa, focusing on four nature reserves – Tsolwana, Hluleka, Mkambati and Great Fish River. The objectives of the study were to: I I. Compare the vegetation productivity inside and outside, as well as land cover change in four nature reserves, as an indicator of conservation effectiveness. II II. Evaluate the relationship between biodiversity conservation and livelihoods in four nature reserves. III III. Evaluate how people’s expectations of nature reserves and perceptions towards nature reserve influence their support of conservation activities. Four hundred semi-structured questionnaires were administered to household heads of communities living at various distances from the four nature reserves, using a gradient design (based on distance). The motive of using distance was to assess whether livelihood status varied with distance from the nature reserves, since data on livelihood before the reserves’ establishment could not be obtained. Through a questionnaire survey, data on demographic information, livelihood assets, livelihood activities, livelihood strategies, livelihood trends, and impacts of the reserves on local communities were gathered. Focus group interviews were also conducted to complement the household surveys. A chi-square test was used to test if there was a relationship between distance from the reserves’ boundaries and local communities’ state of livelihoods. NVivo was used to analyse qualitative data Themes substantiated using literature. The study finds that the reserves did not have any impact on livelihood assets because most households in the study area did not directly depend on the resources found in the reserves. These households depended mostly on government grants and remittances from relatives working in other areas in the country. The reserves, however, supplied some goods and services to local communities, including meat, jobs, water, building materials, security from wild animals, education, skills development, and recreation. There were also a number of negative impacts associated with the reserves including resource use restrictions, harassment by reserves management, killing of domestic animals, and attacks on humans by wild animals escaping from the reserve. The majority (60%) of locals had substantive knowledge of the reserves’ role because of this awareness, 79% were supportive of reserves. However, there were mixed views by locals on the best way to manage these reserves. The most dominant view was that natural resources should be preserved for future generations, while meeting the current generation’s livelihood needs. Other lesser views included that the reserves’ management should involve locals in the management structures, either as active members or through consultation. Similarly, there were people feeling that the reserve is an obstacle to their livelihoods and should be closed and the land returned to the rightful owners. The vegetation productivity was better inside as compared to the outside the reserves. This activity also improved in the sixteen (16) years under assessment. This imply that the ecological functionality of the reserves is better than the surrounding areas and is improving with time. The research recommended that local communities could be an asset in conservation since most of them were in favour of the reserves. This, however, will need reserve managers to form workable partnerships with these communities, where the rights and responsibilities for both parties are defined. Besides these partnerships, lease agreements between local communities and reserves management to enhance benefits to the communities could encourage local communities to take pride in the natural resources within the reserves. This will ultimately becoming stewards to these resources. Development of tourism infrastructure such as curio shops and convenience stores to enhance livelihood opportunities could also help. For the local communities to be well represented it is important that the committees representing them in the various reserve matters be expanded and democratically elected. Where necessary, community awareness programmes on the importance of the reserves and the roles of local communities should be implemented.
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Bioelectrocatalysis and surface analysis of gold coated with nickel oxide/hydroxide and glucose oxidase towards detection of glucose:
- Njoko, Nqobile, Louzada, Marcel, Britton, Jonathan, Khene, Samson M, Nyokong, Tebello, Mashazi, Philani N
- Authors: Njoko, Nqobile , Louzada, Marcel , Britton, Jonathan , Khene, Samson M , Nyokong, Tebello , Mashazi, Philani N
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/150071 , vital:38937 , https://doi.org/10.1016/j.colsurfb.2020.110981
- Description: The fabricating of metal oxide thin films onto conducting surfaces continues to grow and their potential applications as surfaces for biosensor applications is of paramount importance. The correct orientation of glucose oxidase redox enzymes yields very important biointerfaces capable of selectively detecting D-glucose as a measure of blood sugar for healthy and diabetic sick patients. The electrodeposition of redox enzymes, such as glucose oxidase enzymes, onto gold electrode surfaces pre-modified with nickel oxide was investigated in this work.
- Full Text:
- Authors: Njoko, Nqobile , Louzada, Marcel , Britton, Jonathan , Khene, Samson M , Nyokong, Tebello , Mashazi, Philani N
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/150071 , vital:38937 , https://doi.org/10.1016/j.colsurfb.2020.110981
- Description: The fabricating of metal oxide thin films onto conducting surfaces continues to grow and their potential applications as surfaces for biosensor applications is of paramount importance. The correct orientation of glucose oxidase redox enzymes yields very important biointerfaces capable of selectively detecting D-glucose as a measure of blood sugar for healthy and diabetic sick patients. The electrodeposition of redox enzymes, such as glucose oxidase enzymes, onto gold electrode surfaces pre-modified with nickel oxide was investigated in this work.
- Full Text: