A comparison of Grade 10 Mathematics classroom-based test items and the end-of-year national examinations, using Stein's framework of cognitive demands : a Namibian case study
- Authors: Ihonya, Saima Namupa
- Date: 2015
- Subjects: Mathematics -- Study and teaching (Secondary) -- Namibia -- Ohangwena , Educational tests and measurements -- Namibia -- Ohangwena , Cognitive learning , Critical thinking , Examinations -- Namibia -- Ohangwena
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:2032 , http://hdl.handle.net/10962/d1017343
- Description: This study researched the nature of tasks used in Grade 10 mathematics tests and end-of-year national examinations. The study was carried out in three, purposively selected, Grade 10 schools in the Ohangwena region in Northern Namibia. For the purpose of this study, a mixed method approach was employed to analyse a combination of both quantitative and qualitative data. A sample of three tests per mathematics teacher from the three participating schools and national examinations question papers for the past three consecutive years (2011-2013) were analysed using Stein, Smith, Henningsen, & Silver’s (2000) framework of cognitive demand. The study was divided into two phases. Phase 1 was the analysis of teacher test items and national examination items in terms of their cognitive demand. Phase 2 involved semi-structured interviews with three selected teachers to probe their views and find out their basis for selecting test items. The findings of this study revealed that there was no substantial difference in the distribution of the levels of cognitive demand in both tests and national examinations items. The study, however, showed that mainly tasks requiring only procedures without connections dominated the tests and the examinations. The number of higher level tasks in both tests and examinations analysed was low. There was no single task coded at level 4 in any of the teachers’ tests. Only 2% of tasks could be classified at level 4 in the examination items. The study also revealed that since tests and examinations assess the same learning objectives from the syllabus, most of the test items set by teachers were extracted from the national examinations question papers. The paper recommends that more tasks at a higher level category need to be included in assessment tasks to promote critical thinking amongst learners.
- Full Text:
- Date Issued: 2015
- Authors: Ihonya, Saima Namupa
- Date: 2015
- Subjects: Mathematics -- Study and teaching (Secondary) -- Namibia -- Ohangwena , Educational tests and measurements -- Namibia -- Ohangwena , Cognitive learning , Critical thinking , Examinations -- Namibia -- Ohangwena
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:2032 , http://hdl.handle.net/10962/d1017343
- Description: This study researched the nature of tasks used in Grade 10 mathematics tests and end-of-year national examinations. The study was carried out in three, purposively selected, Grade 10 schools in the Ohangwena region in Northern Namibia. For the purpose of this study, a mixed method approach was employed to analyse a combination of both quantitative and qualitative data. A sample of three tests per mathematics teacher from the three participating schools and national examinations question papers for the past three consecutive years (2011-2013) were analysed using Stein, Smith, Henningsen, & Silver’s (2000) framework of cognitive demand. The study was divided into two phases. Phase 1 was the analysis of teacher test items and national examination items in terms of their cognitive demand. Phase 2 involved semi-structured interviews with three selected teachers to probe their views and find out their basis for selecting test items. The findings of this study revealed that there was no substantial difference in the distribution of the levels of cognitive demand in both tests and national examinations items. The study, however, showed that mainly tasks requiring only procedures without connections dominated the tests and the examinations. The number of higher level tasks in both tests and examinations analysed was low. There was no single task coded at level 4 in any of the teachers’ tests. Only 2% of tasks could be classified at level 4 in the examination items. The study also revealed that since tests and examinations assess the same learning objectives from the syllabus, most of the test items set by teachers were extracted from the national examinations question papers. The paper recommends that more tasks at a higher level category need to be included in assessment tasks to promote critical thinking amongst learners.
- Full Text:
- Date Issued: 2015
Nanomaterial modified electrodes : optimization of voltammetric sensors for pharmaceutical and industrial application
- Authors: Brimecombe, Rory Dennis
- Date: 2011
- Subjects: Voltammetry , Electrochemistry , Nanotubes , Nanostructured materials
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4101 , http://hdl.handle.net/10962/d1009721
- Description: Nanomaterials, in particular carbon nanotubes have been shown to exhibit favourable properties for the enhancement of electrochemical detection of target analytes in complex matrices. There is however scope for improvement in terms of the optimization thereof in electrochemical sensors surface modification. The aim of this thesis was to examine methods that would result in increased current response, lowered passivation and application of such modified surfaces with application to pharmaceutically and industrially relevant analytes. Current methods for enhancing the performance of carbon nanotubes include acid functionalization which not only increases the hydrophilicity of the nanotubes, and consequently their ability to provide stable (aqueous) suspensions, but also introduces electrochemically active sites. This particular approach is however not normalized in the literature. Over-exposure to acid treatment results in loss of structural integrity of the carbon nanotubes, and as such a fine balance exists between achieving these dual outcomes. Guided by high resolution scanning electron microscopy, atomic force microscopy, voltammetric and impedance studies, this thesis examined the role of the length of time of the acid functionalization process as well as the impact of activation of carbon nanotubes and fullerenes on electrochemical sensor performance. Based on desired charge transfer resistances, rate transfer coefficients and sensitivity towards redox probes the optimal length of acid functionalization for multiwalled carbon nanotubes was 9 hours and 4 hours for single-walled carbon nanotubes. Further improvements in the desired outcomes were achieved through electrochemical activation of the modified electrode surface by cycling in the presence of catechol, in a novel approach. By employing electrochemical impedance spectroscopy it was observed that catechol activation resulted in lowered charge transfer resistance, before and after activation, with functionalized multi-walled carbon nanotubes (9 hours) exhibiting the greatest decrease of 90 % and functionalized single-walled carbon nanotubes (4 hours), a 50 % decrease. Corresponding increases in the heterologous rate transfer coefficient showed a 770 % increase for functionalized multi-walled carbon nanotubes (9 hours), following catechol activation. Comparative observations for fullerenes following partial reduction in potassium hydroxide yielded a 30 % decrease in charge transfer resistance, with an increased heterologous rate transfer coefficient at a fullerene modified surface The performance of the nanomaterial modified electrodes was applied to the detection of wortmannin with applications in bioprocess control and in the pharmaceutical sector as well as to the detection and monitoring of the industrial dye Reactive red. Of particular relevance to these analytes was the assessment of the nanomaterial modified electrodes for enhanced stability, reproducibility, sensitivity and decreased passivation effects. In this study the first known account of wortmannin detection through electrochemical methods is reported. Voltammetric characterization of wortmannin revealed an irreversible cathodic process with a total number of 4 electrons and a diffusion coefficient of 1.19 x 10-7 cm².s⁻¹. At a functionalized multiwalled carbon nanotubes modified glassy carbon electrode a limit of detection of 0.128 nmol.cm⁻³ was obtained, and with limited surface passivation the detection scheme afforded pertinent analyses in biological media representing a substantial improvement over chromatographic detection methods. This study also provided the first account of the voltammetric detection of reactive red, competing favourably with traditional spectroscopic methods for monitoring biodegradation of this compound in real time.
- Full Text:
- Date Issued: 2011
- Authors: Brimecombe, Rory Dennis
- Date: 2011
- Subjects: Voltammetry , Electrochemistry , Nanotubes , Nanostructured materials
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4101 , http://hdl.handle.net/10962/d1009721
- Description: Nanomaterials, in particular carbon nanotubes have been shown to exhibit favourable properties for the enhancement of electrochemical detection of target analytes in complex matrices. There is however scope for improvement in terms of the optimization thereof in electrochemical sensors surface modification. The aim of this thesis was to examine methods that would result in increased current response, lowered passivation and application of such modified surfaces with application to pharmaceutically and industrially relevant analytes. Current methods for enhancing the performance of carbon nanotubes include acid functionalization which not only increases the hydrophilicity of the nanotubes, and consequently their ability to provide stable (aqueous) suspensions, but also introduces electrochemically active sites. This particular approach is however not normalized in the literature. Over-exposure to acid treatment results in loss of structural integrity of the carbon nanotubes, and as such a fine balance exists between achieving these dual outcomes. Guided by high resolution scanning electron microscopy, atomic force microscopy, voltammetric and impedance studies, this thesis examined the role of the length of time of the acid functionalization process as well as the impact of activation of carbon nanotubes and fullerenes on electrochemical sensor performance. Based on desired charge transfer resistances, rate transfer coefficients and sensitivity towards redox probes the optimal length of acid functionalization for multiwalled carbon nanotubes was 9 hours and 4 hours for single-walled carbon nanotubes. Further improvements in the desired outcomes were achieved through electrochemical activation of the modified electrode surface by cycling in the presence of catechol, in a novel approach. By employing electrochemical impedance spectroscopy it was observed that catechol activation resulted in lowered charge transfer resistance, before and after activation, with functionalized multi-walled carbon nanotubes (9 hours) exhibiting the greatest decrease of 90 % and functionalized single-walled carbon nanotubes (4 hours), a 50 % decrease. Corresponding increases in the heterologous rate transfer coefficient showed a 770 % increase for functionalized multi-walled carbon nanotubes (9 hours), following catechol activation. Comparative observations for fullerenes following partial reduction in potassium hydroxide yielded a 30 % decrease in charge transfer resistance, with an increased heterologous rate transfer coefficient at a fullerene modified surface The performance of the nanomaterial modified electrodes was applied to the detection of wortmannin with applications in bioprocess control and in the pharmaceutical sector as well as to the detection and monitoring of the industrial dye Reactive red. Of particular relevance to these analytes was the assessment of the nanomaterial modified electrodes for enhanced stability, reproducibility, sensitivity and decreased passivation effects. In this study the first known account of wortmannin detection through electrochemical methods is reported. Voltammetric characterization of wortmannin revealed an irreversible cathodic process with a total number of 4 electrons and a diffusion coefficient of 1.19 x 10-7 cm².s⁻¹. At a functionalized multiwalled carbon nanotubes modified glassy carbon electrode a limit of detection of 0.128 nmol.cm⁻³ was obtained, and with limited surface passivation the detection scheme afforded pertinent analyses in biological media representing a substantial improvement over chromatographic detection methods. This study also provided the first account of the voltammetric detection of reactive red, competing favourably with traditional spectroscopic methods for monitoring biodegradation of this compound in real time.
- Full Text:
- Date Issued: 2011
Exploration of Nahoon beach milieu for lignocellulose degrading bacteria and optimizing fermentation conditions for holocellulase production by selected strains
- Authors: Fatokun, Evelyn
- Date: 2016
- Subjects: Lignocellulose Lignocellulose -- Biodegradation Water -- Purification -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10353/1529 , vital:27413
- Description: A significant trend in the modern day industrial biotechnology is the utilization and application of renewable resources, and ecofriendly approach to industrial processes and waste management. As a consequence thereof, the biotechnology of holocellulases: cellulase and xylanase and, enzymatic hydrolysis of renewable and abundant lignocellulosic biomass to energy and value added products are rapidly increasing; hence, cost effective enzyme system is imperative. In that context, exploration of microbiota for strains and enzymes with novel industrial properties is vital for efficient and commercially viable enzyme biotechnology. Consequent on the complex characteristics of high salinity, variable pressure, temperature and nutritional conditions, bacterial strains from the marine environment are equipped with enzyme machinery of industrial importance for adaptation and survival. In this study, bacterial strains were isolated form Nahoon beach and optimized for holocellulase production. Three isolates selected for lignocellulolytic potential were identified by 16S ribosomal deoxyribonucleic acid (rDNA) sequence analysis. Isolate FS1k had 98 percent similarity with Streptomyces albidoflavus strain AIH12, was designated as Streptomyces albidoflavus strain SAMRC-UFH5 and deposited in the GenBank with accession number KU171373. Similarly, isolates CS14b and CS22d with respective percentage similarity of 98 and 99 (percent) with Bacillus cereus strains and Streptomyces sp. strain WMMB251 were named Bacillus cereus strain SAMRC-UFH9 and Streptomyces sp. strain SAMRC-UFH6; and were deposited in the GenBank with accession number KX524510 and KU171374 respectively. Optimal pH, temperature and agitation speed for cellulase production by S. albidoflavus strain SAMRC-UFH5, and B. cereus strain SAMRC-UFH9 were 6 and 7; 40 and 30 (°C); and 100 and 150 (rpm) respectively; while xylanase production was optimal at pH, temperature and agitation speed of 8 and 7; 40 and 30 (°C); and 150 and 50 (rpm) respectively. Maximum cellulase activity of 0.26 and 0.061(U/mL) by S. albidoflavus strain SAMRC-UFH5 and B. cereus strain SAMRC-UFH9 were attained at 60 h respectively, while maximal xylanase activity of 18.54 and 16.6 (U/mL) was produced by S. albidoflavus strain SAMRC-UFH5 and B. cereus strain SAMRC-UFH9 at 48 h and 60 h respectively. Furthermore, xylanase production by S. albidoflavus strain SAMRC-UFH5 and B. cereus strain SAMRC-UFH9 was maximally induced by wheat straw and xylan respectively, while cellulase production was best induced by mannose and carboxymethyl cellulose respectively. On the other hand, cellulase and xylanase production by Streptomyces sp. strain SAMRC-UFH6 was optimal at pH, temperature and agitation speed of 7 and 8, 40 °C and 100 rpm, respectively. Highest production of cellulase and xylanase was attained at 84 and 60 h with respective activity of 0.065 and 6.34 (U/mL). In addition, cellulase and xylanase production by the strain was best induced by beechwood xylan. Moreover, xylanase produced by Streptomyces sp. strain SAMRC-UFH6 at optimal conditions was characterized by optimal pH and temperature of 8 and 80-90 °C respectively; retaining over 70 percent activity at pH 5-10 after 1 h and 60 percent of initial activity at 90 °C after 90 min of incubation. In all, optimization improved cellulase and xylanase production yields, being 40 and 95.5, 10.89 and 72.17, and 10 and 115- fold increase by S. albidoflavus strain SAMRC-UFH5, B. cereus strain SAMRC-UFH9 and Streptomyces sp. SAMRC-UFH6 respectively. The results of this study suggest that the marine bacterial strains are resource for holocellulase with industrial applications.
- Full Text:
- Date Issued: 2016
- Authors: Fatokun, Evelyn
- Date: 2016
- Subjects: Lignocellulose Lignocellulose -- Biodegradation Water -- Purification -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10353/1529 , vital:27413
- Description: A significant trend in the modern day industrial biotechnology is the utilization and application of renewable resources, and ecofriendly approach to industrial processes and waste management. As a consequence thereof, the biotechnology of holocellulases: cellulase and xylanase and, enzymatic hydrolysis of renewable and abundant lignocellulosic biomass to energy and value added products are rapidly increasing; hence, cost effective enzyme system is imperative. In that context, exploration of microbiota for strains and enzymes with novel industrial properties is vital for efficient and commercially viable enzyme biotechnology. Consequent on the complex characteristics of high salinity, variable pressure, temperature and nutritional conditions, bacterial strains from the marine environment are equipped with enzyme machinery of industrial importance for adaptation and survival. In this study, bacterial strains were isolated form Nahoon beach and optimized for holocellulase production. Three isolates selected for lignocellulolytic potential were identified by 16S ribosomal deoxyribonucleic acid (rDNA) sequence analysis. Isolate FS1k had 98 percent similarity with Streptomyces albidoflavus strain AIH12, was designated as Streptomyces albidoflavus strain SAMRC-UFH5 and deposited in the GenBank with accession number KU171373. Similarly, isolates CS14b and CS22d with respective percentage similarity of 98 and 99 (percent) with Bacillus cereus strains and Streptomyces sp. strain WMMB251 were named Bacillus cereus strain SAMRC-UFH9 and Streptomyces sp. strain SAMRC-UFH6; and were deposited in the GenBank with accession number KX524510 and KU171374 respectively. Optimal pH, temperature and agitation speed for cellulase production by S. albidoflavus strain SAMRC-UFH5, and B. cereus strain SAMRC-UFH9 were 6 and 7; 40 and 30 (°C); and 100 and 150 (rpm) respectively; while xylanase production was optimal at pH, temperature and agitation speed of 8 and 7; 40 and 30 (°C); and 150 and 50 (rpm) respectively. Maximum cellulase activity of 0.26 and 0.061(U/mL) by S. albidoflavus strain SAMRC-UFH5 and B. cereus strain SAMRC-UFH9 were attained at 60 h respectively, while maximal xylanase activity of 18.54 and 16.6 (U/mL) was produced by S. albidoflavus strain SAMRC-UFH5 and B. cereus strain SAMRC-UFH9 at 48 h and 60 h respectively. Furthermore, xylanase production by S. albidoflavus strain SAMRC-UFH5 and B. cereus strain SAMRC-UFH9 was maximally induced by wheat straw and xylan respectively, while cellulase production was best induced by mannose and carboxymethyl cellulose respectively. On the other hand, cellulase and xylanase production by Streptomyces sp. strain SAMRC-UFH6 was optimal at pH, temperature and agitation speed of 7 and 8, 40 °C and 100 rpm, respectively. Highest production of cellulase and xylanase was attained at 84 and 60 h with respective activity of 0.065 and 6.34 (U/mL). In addition, cellulase and xylanase production by the strain was best induced by beechwood xylan. Moreover, xylanase produced by Streptomyces sp. strain SAMRC-UFH6 at optimal conditions was characterized by optimal pH and temperature of 8 and 80-90 °C respectively; retaining over 70 percent activity at pH 5-10 after 1 h and 60 percent of initial activity at 90 °C after 90 min of incubation. In all, optimization improved cellulase and xylanase production yields, being 40 and 95.5, 10.89 and 72.17, and 10 and 115- fold increase by S. albidoflavus strain SAMRC-UFH5, B. cereus strain SAMRC-UFH9 and Streptomyces sp. SAMRC-UFH6 respectively. The results of this study suggest that the marine bacterial strains are resource for holocellulase with industrial applications.
- Full Text:
- Date Issued: 2016
“The stranger at home” : representations of home and hospitality in three South African post-transitional novels
- Authors: Dass, Minesh
- Date: 2014
- Subjects: South African fiction (English) -- History and criticism , Wicomb, Zoë -- Criticism and interpretation , Shukri, Ishtiyaq, 1968- -- Criticism and interpretation , Vladislavić, Ivan, 1957- -- Criticism and interpretation , Home in literature , Hospitality in literature
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2325 , http://hdl.handle.net/10962/d1016355
- Description: This thesis examines the representation of home and hospitality in Zoë Wicomb’s Playing in the Light, Ishtiyaq Shukri’s The Silent Minaret, and Ivan Vladislavić’s Double Negative. It attempts to trace the un-homeliness of the central characters and to account for their feelings of discomfort. As such, it argues that the home is incapable of being inviolable because the invasion of the public is always a possibility. The implication is that master narratives such as race, history and politics are always entering the space one constructs as private. That said, this study also argues that the home and those things with which it is most closely associated, such as belonging, comfort and safety, may actually hide a form of violence. By this I mean that in the desire for homeliness, one may exclude others from one’s home. Consequently, this argument draws on Jacques Derrida’s writings on the aporia of conditional and unconditional hospitality to investigate what ethical possibilities might, somewhat unexpectedly, be created by the un-homely home. The study is therefore an exploration of the potentials that inhere in a certain kind of un-homeliness, the most important of which is the chance to respond ethically to the alterity of the other. In sum, there is a necessity to extend hospitality beyond condition and beyond limit, and this ethical imperative is at odds with the desire for comfort and safety. The way in which post-transitional novels explore these issues of hospitality and home is the primary focus of this study.
- Full Text:
- Date Issued: 2014
- Authors: Dass, Minesh
- Date: 2014
- Subjects: South African fiction (English) -- History and criticism , Wicomb, Zoë -- Criticism and interpretation , Shukri, Ishtiyaq, 1968- -- Criticism and interpretation , Vladislavić, Ivan, 1957- -- Criticism and interpretation , Home in literature , Hospitality in literature
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2325 , http://hdl.handle.net/10962/d1016355
- Description: This thesis examines the representation of home and hospitality in Zoë Wicomb’s Playing in the Light, Ishtiyaq Shukri’s The Silent Minaret, and Ivan Vladislavić’s Double Negative. It attempts to trace the un-homeliness of the central characters and to account for their feelings of discomfort. As such, it argues that the home is incapable of being inviolable because the invasion of the public is always a possibility. The implication is that master narratives such as race, history and politics are always entering the space one constructs as private. That said, this study also argues that the home and those things with which it is most closely associated, such as belonging, comfort and safety, may actually hide a form of violence. By this I mean that in the desire for homeliness, one may exclude others from one’s home. Consequently, this argument draws on Jacques Derrida’s writings on the aporia of conditional and unconditional hospitality to investigate what ethical possibilities might, somewhat unexpectedly, be created by the un-homely home. The study is therefore an exploration of the potentials that inhere in a certain kind of un-homeliness, the most important of which is the chance to respond ethically to the alterity of the other. In sum, there is a necessity to extend hospitality beyond condition and beyond limit, and this ethical imperative is at odds with the desire for comfort and safety. The way in which post-transitional novels explore these issues of hospitality and home is the primary focus of this study.
- Full Text:
- Date Issued: 2014
Towards a holistic view of land and water management in the Gamtoos River catchment: applying a political geoecology approach
- Authors: Robb, Breanne Nicola
- Date: 2017
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/7914 , vital:21323
- Description: The Eastern Cape of South Africa is characterised by water scarcity, constraint on usage, and inter-basin transfers. Water from the Gamtoos River catchment supplies water users both within the catchment and outside the catchment boundaries. This requires careful management of water and land to prevent overexploitation. However, management is complex as it is divided among various stakeholders with differing interests. Political geoecology is an approach that has the potential to provide holistic insight into the catchment’s water context. It was proposed to account for spatial patterns underlying interrelationships between resource distribution, human productive activity, and power relations by integrating the fields of political ecology and geoecology. This research was undertaken to further develop political geoecology as an approach for examining human-environment relations in geography through a case study of land and water management in the Gamtoos River catchment and its subcatchments. Distribution of resources and human influences were elucidated through generation of maps. To facilitate spatial analysis, the study area was delineated into catchment zones. Additionally, stakeholders were identified and classified at local, regional, national, and international levels. Power relations between stakeholders were investigated through qualitative content analysis of transcribed semi-structured interviews and survey questionnaires that were administered to 34 research participants (selected through purposive and snowball sampling) directly involved in resource management in the catchment. Findings were spatially interpreted for each of the zones. The source zone was characterised by natural vegetation, steep, rugged topography, limited access ability, and power relations around restoration and conservation interests, which arose most significantly in the Baviaanskloof. The natural recapture zone was characterised by irrigated cultivation in areas of less harsh terrain in the upstream (Baviaanskloof and Kouga) sub-catchments. In the marginal Baviaanskloof, localised power relations over water distribution primarily arose. In the thriving commercial farming context of the Kouga, power relations included a local upstream-downstream legal conflict, competing levels of governance, issues with establishing water users’ associations (WUAs), and lack of adequate implementation of processes by government. Regional power relations are most prominent in the thriving commercial farming context of the overlapping regulated recapture and final use zones in the downstream Gamtoos sub-catchment. The reliance on upstream sub-catchments and tensions with the city of Port Elizabeth over water use are mediated through decisions made at the national level. Non-location specific power relations included indirect influence through energy, markets, and standards organisations, barriers in government preventing successful process implementation, and equity issues (particularly limiting the success of emerging farmers). These results illustrated that resource distribution, human productive activity, and power relations combine to produce unique characteristics in each of the zones in the Gamtoos catchment. The application of political geoecology in this case study situated the approach as useful for examining human- environment relations in geography.
- Full Text:
- Date Issued: 2017
- Authors: Robb, Breanne Nicola
- Date: 2017
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/7914 , vital:21323
- Description: The Eastern Cape of South Africa is characterised by water scarcity, constraint on usage, and inter-basin transfers. Water from the Gamtoos River catchment supplies water users both within the catchment and outside the catchment boundaries. This requires careful management of water and land to prevent overexploitation. However, management is complex as it is divided among various stakeholders with differing interests. Political geoecology is an approach that has the potential to provide holistic insight into the catchment’s water context. It was proposed to account for spatial patterns underlying interrelationships between resource distribution, human productive activity, and power relations by integrating the fields of political ecology and geoecology. This research was undertaken to further develop political geoecology as an approach for examining human-environment relations in geography through a case study of land and water management in the Gamtoos River catchment and its subcatchments. Distribution of resources and human influences were elucidated through generation of maps. To facilitate spatial analysis, the study area was delineated into catchment zones. Additionally, stakeholders were identified and classified at local, regional, national, and international levels. Power relations between stakeholders were investigated through qualitative content analysis of transcribed semi-structured interviews and survey questionnaires that were administered to 34 research participants (selected through purposive and snowball sampling) directly involved in resource management in the catchment. Findings were spatially interpreted for each of the zones. The source zone was characterised by natural vegetation, steep, rugged topography, limited access ability, and power relations around restoration and conservation interests, which arose most significantly in the Baviaanskloof. The natural recapture zone was characterised by irrigated cultivation in areas of less harsh terrain in the upstream (Baviaanskloof and Kouga) sub-catchments. In the marginal Baviaanskloof, localised power relations over water distribution primarily arose. In the thriving commercial farming context of the Kouga, power relations included a local upstream-downstream legal conflict, competing levels of governance, issues with establishing water users’ associations (WUAs), and lack of adequate implementation of processes by government. Regional power relations are most prominent in the thriving commercial farming context of the overlapping regulated recapture and final use zones in the downstream Gamtoos sub-catchment. The reliance on upstream sub-catchments and tensions with the city of Port Elizabeth over water use are mediated through decisions made at the national level. Non-location specific power relations included indirect influence through energy, markets, and standards organisations, barriers in government preventing successful process implementation, and equity issues (particularly limiting the success of emerging farmers). These results illustrated that resource distribution, human productive activity, and power relations combine to produce unique characteristics in each of the zones in the Gamtoos catchment. The application of political geoecology in this case study situated the approach as useful for examining human- environment relations in geography.
- Full Text:
- Date Issued: 2017
Employee motivation, workplace surveillance and employee engagement among selected Zimbabwe revenue authority employees
- Tsvangirai, Fidelis Pedzisai
- Authors: Tsvangirai, Fidelis Pedzisai
- Date: 2018
- Subjects: Employee motivation Employee motivation--Zimbabwe Organizational effectiveness--Zimbabwe
- Language: English
- Type: Thesis , Doctoral , Industrial Psychology
- Identifier: http://hdl.handle.net/10353/17384 , vital:40961
- Description: Orientation: The study is located in the micro environmental circumstances in Zimbabwe where the size of the informal sector is overtaking that of the formal sector. The country is experiencing a high labour turnover averaging at 19percent per year due to an unstable economic setting. The Zimbabwe Revenue Authority (ZIMRA) is experiencing an employee engagement score as low as 2.1 out of 5. This low employee engagement level and high labour turnover call for employers to find strategies not only to keep their employees motivated and engaged but also to monitor how they work. Research purpose: The study sought to examine how employee motivation mediates between workplace surveillance and employee engagement among selected employees at the Zimbabwe Revenue Authority (ZIMRA). Motivation of the study: Public organisations often face the criticism that they do not deliver the quality of service expected and one in every five of their employees is disengaged from their work. ZIMRA’s mandate has a significant impact on the country’s gross domestic product (GDP) and the organisation needs to deliver against all odds. Currently no research exists which provides information on the mediating effect of employee motivation on the relationship between workplace surveillance and employee engagement in Zimbabwe. Research philosophy, design and method: This study adopted the positivism research philosophy and a survey research design, which is quantitative and descriptive in nature. The study utilised the principles of structural equation modelling (SEM) in formulating the research hypotheses and in data analysis. Main findings: The findings of the study, through utilising SEM, were that a negative relationship exists between workplace surveillance and employee engagement and that employee motivation has a positive significant relationship with employee engagement. The study also found that workplace surveillance positively relates to employee motivation. The study also found that employee motivation partially mediates the relationship between workplace surveillance and employee engagement. Practical/Managerial implications: A negative relationship between workplace surveillance and employee engagement calls for ZIMRA management to seek employee buy-in when implementing workplace surveillance measures. A positive relationship between employee motivation and employee engagement calls for ZIMRA management to invest much in these two variables. A positive relationship between workplace surveillance and employee motivation calls for ZIMRA management to put in place policies that ensure employees do not abuse work time by doing their own business. Contribution or value-add: The study contributes to the body of knowledge on the debate around the impact of employee motivation as a mediator of the relationship between workplace surveillance and employee engagement. This study agree with the vast amount of literature that the relationship between workplace surveillance and employee motivation is not always negative.
- Full Text:
- Date Issued: 2018
- Authors: Tsvangirai, Fidelis Pedzisai
- Date: 2018
- Subjects: Employee motivation Employee motivation--Zimbabwe Organizational effectiveness--Zimbabwe
- Language: English
- Type: Thesis , Doctoral , Industrial Psychology
- Identifier: http://hdl.handle.net/10353/17384 , vital:40961
- Description: Orientation: The study is located in the micro environmental circumstances in Zimbabwe where the size of the informal sector is overtaking that of the formal sector. The country is experiencing a high labour turnover averaging at 19percent per year due to an unstable economic setting. The Zimbabwe Revenue Authority (ZIMRA) is experiencing an employee engagement score as low as 2.1 out of 5. This low employee engagement level and high labour turnover call for employers to find strategies not only to keep their employees motivated and engaged but also to monitor how they work. Research purpose: The study sought to examine how employee motivation mediates between workplace surveillance and employee engagement among selected employees at the Zimbabwe Revenue Authority (ZIMRA). Motivation of the study: Public organisations often face the criticism that they do not deliver the quality of service expected and one in every five of their employees is disengaged from their work. ZIMRA’s mandate has a significant impact on the country’s gross domestic product (GDP) and the organisation needs to deliver against all odds. Currently no research exists which provides information on the mediating effect of employee motivation on the relationship between workplace surveillance and employee engagement in Zimbabwe. Research philosophy, design and method: This study adopted the positivism research philosophy and a survey research design, which is quantitative and descriptive in nature. The study utilised the principles of structural equation modelling (SEM) in formulating the research hypotheses and in data analysis. Main findings: The findings of the study, through utilising SEM, were that a negative relationship exists between workplace surveillance and employee engagement and that employee motivation has a positive significant relationship with employee engagement. The study also found that workplace surveillance positively relates to employee motivation. The study also found that employee motivation partially mediates the relationship between workplace surveillance and employee engagement. Practical/Managerial implications: A negative relationship between workplace surveillance and employee engagement calls for ZIMRA management to seek employee buy-in when implementing workplace surveillance measures. A positive relationship between employee motivation and employee engagement calls for ZIMRA management to invest much in these two variables. A positive relationship between workplace surveillance and employee motivation calls for ZIMRA management to put in place policies that ensure employees do not abuse work time by doing their own business. Contribution or value-add: The study contributes to the body of knowledge on the debate around the impact of employee motivation as a mediator of the relationship between workplace surveillance and employee engagement. This study agree with the vast amount of literature that the relationship between workplace surveillance and employee motivation is not always negative.
- Full Text:
- Date Issued: 2018
Constraints in attainment of sustainable human settlements at Kwamaphumulo Local Municipality
- Authors: Sikhosana, Phindokuhle
- Date: 2020
- Subjects: Human settlements -- South Africa -- KwaZulu-Natal , Low-income housing -- South Africa -- KwaZulu-Natal City planning Land use, Urban
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/47198 , vital:39826
- Description: This study sought to investigate the constraints in the attainment of sustainable human settlement in KwaMaphumulo Local Municipality at iLembe District in KwaZulu-Natal, South Africa. The aim of this study was to investigate the constraints that limit the achievement of the ideal of sustainable human settlement development in the KwaMaphumulo Local Municipality. Furthermore, the study sought to determine the impact of these constraints on sustainable development and to proffer measures that can be taken to combat stagnant or underdevelopment in the area. A mixed-method approach is followed in this study, which considers a triangulation of quantitative and qualitative data collection, analysis and interpretation techniques. It is important to note that in the past years since South Africa became a democratic country, there have been countless efforts with regard to overcoming the problems created during the apartheid era. These problems stemmed from a distorted spatial, social, economic and political background that was advocated by both segregationist public policies and the planning systems of the Apartheid Regime. In recent years, South African cities have also been faced with environmental issues, which are imperative to the future development of the country. With all these issues in mind, we see that the many efforts that are put in place by government always fall short of solving the problems. This research report looked at the constraints that affect the KwaMaphumulo Local Municipality in attaining sustainable human settlements and whether the efforts of redistribution and equality have been enough to overcome the problems. The key findings of the study were that constraints in attaining sustainable human settlements in the KwaMaphumulo Local Municipality negatively impacts on the development in the area. The level of services being provided is poor. There is an apparent disconnect between traditional leaders and the municipality councillor as development management and vision are concerned. Furthermore, the development programmes and projects do not seem to address the critical needs of the community. Housing development is narrow minded with a focus on the top structure and a failure to include basic services and infrastructure. Houses built that are 6 financed by subsidies are of poor quality. The latter situation results in more able‐ bodied, skilled and capable people emigrating to developed areas.
- Full Text:
- Date Issued: 2020
- Authors: Sikhosana, Phindokuhle
- Date: 2020
- Subjects: Human settlements -- South Africa -- KwaZulu-Natal , Low-income housing -- South Africa -- KwaZulu-Natal City planning Land use, Urban
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/47198 , vital:39826
- Description: This study sought to investigate the constraints in the attainment of sustainable human settlement in KwaMaphumulo Local Municipality at iLembe District in KwaZulu-Natal, South Africa. The aim of this study was to investigate the constraints that limit the achievement of the ideal of sustainable human settlement development in the KwaMaphumulo Local Municipality. Furthermore, the study sought to determine the impact of these constraints on sustainable development and to proffer measures that can be taken to combat stagnant or underdevelopment in the area. A mixed-method approach is followed in this study, which considers a triangulation of quantitative and qualitative data collection, analysis and interpretation techniques. It is important to note that in the past years since South Africa became a democratic country, there have been countless efforts with regard to overcoming the problems created during the apartheid era. These problems stemmed from a distorted spatial, social, economic and political background that was advocated by both segregationist public policies and the planning systems of the Apartheid Regime. In recent years, South African cities have also been faced with environmental issues, which are imperative to the future development of the country. With all these issues in mind, we see that the many efforts that are put in place by government always fall short of solving the problems. This research report looked at the constraints that affect the KwaMaphumulo Local Municipality in attaining sustainable human settlements and whether the efforts of redistribution and equality have been enough to overcome the problems. The key findings of the study were that constraints in attaining sustainable human settlements in the KwaMaphumulo Local Municipality negatively impacts on the development in the area. The level of services being provided is poor. There is an apparent disconnect between traditional leaders and the municipality councillor as development management and vision are concerned. Furthermore, the development programmes and projects do not seem to address the critical needs of the community. Housing development is narrow minded with a focus on the top structure and a failure to include basic services and infrastructure. Houses built that are 6 financed by subsidies are of poor quality. The latter situation results in more able‐ bodied, skilled and capable people emigrating to developed areas.
- Full Text:
- Date Issued: 2020
Genetics, physiology, proteomics of quality protein maize inbred lines under drought and heat stress
- Authors: Pfunde, Cleopatra Nyaradzo
- Date: 2016
- Subjects: Corn Drought-tolerant plants Proteomics
- Language: English
- Type: Thesis , Masters/Doctoral , Crop Science
- Identifier: http://hdl.handle.net/10353/11696 , vital:39098
- Description: When plants perceive heat stress alone or in combination with drought, they activate several responses to synchronize development and molecular activities to ensure survival. In this study, a multidiscipline approach was adopted to investigate the plant genetics, proteomics and physiology for understanding the mechanisms underlying the adaptive response to combined drought and heat stress. The quality protein maize (QPM) inbred lines used had varied degrees of tolerance to both heat stress alone and in combination with drought. The overall objective of this study was to identify drought and heat tolerant germplasm that combine well under drought and heat stress for use in breeding programs to develop new QPM varieties. Initially, the genetic diversity among available inbred lines was estimated using two molecular markers, simple sequence repeats (SSRs) and single nucleotide polymorphisms (SNPs). The results indicated that moderate diversity exists among the QPM inbred lines which can be exploited to generate high performing hybrids. Cross combinations between QS26 and CIM2 and those between QS6 and CIM14 were selected as crosses likely to give substantial heterosis in the field because of the high genetic distances that were found between them using SNPs. Screening of inbred lines for drought and heat tolerance was done at the early germination and seedling stages. Differences in heat tolerance at both stages of growth were observed. Heat tolerant inbred lines at early germination stage had longer coleoptiles and radicles after recovery. The following inbred lines exhibited acquired thermo-tolerance, QS6, CIM7, QS17 and QS19, while CIM12, QS1, CIM21 and QS32 showed basal thermo-tolerance. At the early seedling stage inbred lines with significant differences (P< 0.001) in morpho-physiological traits were noted under heat stress alone and under combined drought and heat stress. However, no significant differences were noted for morpho-physiological measurements in the control treatment. Electron transport rate, sub-stomatal CO2, and stomatal conductance were significantly (P<0.001) reduced in response to combined drought and heat stress. Thus, drought coupled with heat stress resulted in stomatal closure, decreased photosynthetic rate, enhanced respiration and increased leaf temperature for susceptible inbred lines. The combined effects of drought and heat stress were more deleterious than the individual effect of heat stress alone as indicated by the reduction in dry weight. Based on the physiological parameters, biomass and tolerance indices, inbred lines QS22, CIM18 and QS6 showed tolerance to combined drought and heat stress, while CIM18, QS14 and QS30 exhibited thermo-tolerance. Inbred line CIM18 showed cross tolerance to combined drought and heat stress, and to heat stress alone. Further investigations into the comparative proteomic analysis of CIM18 (tolerant) with QS21 (susceptible) under combined drought and heat stress at seedling stage revealed that photosynthetic and stress related proteins were upregulated in CIM18. In addition, the abundance of heat shock proteins such as HSP70 and sHSP 17.8 kDa meant that CIM18 was better able to maintain cellular homeostasis and metabolism. The presence of metabolism related proteins meant that the energy needs of photosynthesis and other activities were met under drought and heat stress. Anti-oxidant enzymes such as glutathione s transferase were responsible for detoxification of reactive oxygen species induced by oxidative stress. These proteins mediated tolerance to combined stress in CIM18. The proteins that were micro-sequenced have previously been identified in individual drought and heat stress studies. The expression of these proteins under combined stress indicated that mechanisms from both stresses were pooled to confer tolerance in CIM18. Accordingly, the study proposes that CIM18 is a drought and heat tolerant QPM inbred line and is recommended for inclusion in breeding programs aimed at the development of drought and heat tolerant varieties. QPM has the potential to improve human nutrition in several rural households. The combining ability analysis of inbred lines revealed that GCA effects under combined drought and heat stress were significant for ears per plant, chlorophyll content, canopy temperature, anthesis silking interval, days to 50percent silking and ear length. Specific combining ability effects were significant for grain yield, days to 50percent anthesis, chlorophyll content and senescence. The study revealed that non-additive gene action was more important in determining grain yield under combined drought and heat stress. Inbred lines L2, L3, L7 and L3, L7 and L11 were good sources of genes for high grain yield under well-watered and combined drought and heat stress respectively. Cross combinations L3 x L13 (3.05 t/ha) and L5 x L9 (2.95 t/ha) were the best performing single cross hybrids for grain yield while cross combination L2 x L10 (1.33t/ha) was the least performing hybrid under combined stress conditions. Under well-watered conditions, the highest yielding crosses were between L2 x L13 (6.51t/ha) and L2 x L8 (6.46 t/ha). The inbred lines identified as sources of drought and heat tolerance and the high yielding cross combinations maybe useful for improving tolerance by generating hybrids or synthetic QPM maize varieties. The inbred lines which exhibited tolerance to both drought and heat stress were genetically diverse and were able to maintain photosynthesis and hence growth during stressful conditions. The ability of these genotypes to accumulate biomass or produce yield under stressful conditions highlights underlying mechanisms which need to be further exploited. While partial proteomic work was done in this study, a more comprehensive study looking into greater depth at the genes responsible for these mechanisms is paramount to fully utilize and/or transfer these genes to other desirable genotypes.
- Full Text:
- Date Issued: 2016
Genetics, physiology, proteomics of quality protein maize inbred lines under drought and heat stress
- Authors: Pfunde, Cleopatra Nyaradzo
- Date: 2016
- Subjects: Corn Drought-tolerant plants Proteomics
- Language: English
- Type: Thesis , Masters/Doctoral , Crop Science
- Identifier: http://hdl.handle.net/10353/11696 , vital:39098
- Description: When plants perceive heat stress alone or in combination with drought, they activate several responses to synchronize development and molecular activities to ensure survival. In this study, a multidiscipline approach was adopted to investigate the plant genetics, proteomics and physiology for understanding the mechanisms underlying the adaptive response to combined drought and heat stress. The quality protein maize (QPM) inbred lines used had varied degrees of tolerance to both heat stress alone and in combination with drought. The overall objective of this study was to identify drought and heat tolerant germplasm that combine well under drought and heat stress for use in breeding programs to develop new QPM varieties. Initially, the genetic diversity among available inbred lines was estimated using two molecular markers, simple sequence repeats (SSRs) and single nucleotide polymorphisms (SNPs). The results indicated that moderate diversity exists among the QPM inbred lines which can be exploited to generate high performing hybrids. Cross combinations between QS26 and CIM2 and those between QS6 and CIM14 were selected as crosses likely to give substantial heterosis in the field because of the high genetic distances that were found between them using SNPs. Screening of inbred lines for drought and heat tolerance was done at the early germination and seedling stages. Differences in heat tolerance at both stages of growth were observed. Heat tolerant inbred lines at early germination stage had longer coleoptiles and radicles after recovery. The following inbred lines exhibited acquired thermo-tolerance, QS6, CIM7, QS17 and QS19, while CIM12, QS1, CIM21 and QS32 showed basal thermo-tolerance. At the early seedling stage inbred lines with significant differences (P< 0.001) in morpho-physiological traits were noted under heat stress alone and under combined drought and heat stress. However, no significant differences were noted for morpho-physiological measurements in the control treatment. Electron transport rate, sub-stomatal CO2, and stomatal conductance were significantly (P<0.001) reduced in response to combined drought and heat stress. Thus, drought coupled with heat stress resulted in stomatal closure, decreased photosynthetic rate, enhanced respiration and increased leaf temperature for susceptible inbred lines. The combined effects of drought and heat stress were more deleterious than the individual effect of heat stress alone as indicated by the reduction in dry weight. Based on the physiological parameters, biomass and tolerance indices, inbred lines QS22, CIM18 and QS6 showed tolerance to combined drought and heat stress, while CIM18, QS14 and QS30 exhibited thermo-tolerance. Inbred line CIM18 showed cross tolerance to combined drought and heat stress, and to heat stress alone. Further investigations into the comparative proteomic analysis of CIM18 (tolerant) with QS21 (susceptible) under combined drought and heat stress at seedling stage revealed that photosynthetic and stress related proteins were upregulated in CIM18. In addition, the abundance of heat shock proteins such as HSP70 and sHSP 17.8 kDa meant that CIM18 was better able to maintain cellular homeostasis and metabolism. The presence of metabolism related proteins meant that the energy needs of photosynthesis and other activities were met under drought and heat stress. Anti-oxidant enzymes such as glutathione s transferase were responsible for detoxification of reactive oxygen species induced by oxidative stress. These proteins mediated tolerance to combined stress in CIM18. The proteins that were micro-sequenced have previously been identified in individual drought and heat stress studies. The expression of these proteins under combined stress indicated that mechanisms from both stresses were pooled to confer tolerance in CIM18. Accordingly, the study proposes that CIM18 is a drought and heat tolerant QPM inbred line and is recommended for inclusion in breeding programs aimed at the development of drought and heat tolerant varieties. QPM has the potential to improve human nutrition in several rural households. The combining ability analysis of inbred lines revealed that GCA effects under combined drought and heat stress were significant for ears per plant, chlorophyll content, canopy temperature, anthesis silking interval, days to 50percent silking and ear length. Specific combining ability effects were significant for grain yield, days to 50percent anthesis, chlorophyll content and senescence. The study revealed that non-additive gene action was more important in determining grain yield under combined drought and heat stress. Inbred lines L2, L3, L7 and L3, L7 and L11 were good sources of genes for high grain yield under well-watered and combined drought and heat stress respectively. Cross combinations L3 x L13 (3.05 t/ha) and L5 x L9 (2.95 t/ha) were the best performing single cross hybrids for grain yield while cross combination L2 x L10 (1.33t/ha) was the least performing hybrid under combined stress conditions. Under well-watered conditions, the highest yielding crosses were between L2 x L13 (6.51t/ha) and L2 x L8 (6.46 t/ha). The inbred lines identified as sources of drought and heat tolerance and the high yielding cross combinations maybe useful for improving tolerance by generating hybrids or synthetic QPM maize varieties. The inbred lines which exhibited tolerance to both drought and heat stress were genetically diverse and were able to maintain photosynthesis and hence growth during stressful conditions. The ability of these genotypes to accumulate biomass or produce yield under stressful conditions highlights underlying mechanisms which need to be further exploited. While partial proteomic work was done in this study, a more comprehensive study looking into greater depth at the genes responsible for these mechanisms is paramount to fully utilize and/or transfer these genes to other desirable genotypes.
- Full Text:
- Date Issued: 2016
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