An investigation into improved ionospheric F1 layer predictions over Grahamstown, South Africa
- Authors: Jacobs, Linda
- Date: 2005
- Subjects: Ionosphere , Ionospheric electron density -- South Africa -- Grahamstown , Neural networks (Computer Science)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5511 , http://hdl.handle.net/10962/d1008094 , Ionosphere , Ionospheric electron density -- South Africa -- Grahamstown , Neural networks (Computer Science)
- Description: This thesis describes an analysis of the F1 layer data obtained from the Grahamstown (33.32°S, 26.500 E), South Africa ionospheric station and the use of this data in improving a Neural Network (NN) based model of the F1 layer of the ionosphere. An application for real-time ray tracing through the South African ionosphere was identified, and for this application real-time evaluation of the electron density profile is essential. Raw real-time virtual height data are provided by a Lowell Digisonde (DPS), which employs the automatic scaling software, ARTIST whose output includes the virtual-toreal height data conversion. Experience has shown that there are times when the ray tracing performance is degraded because of difficulties surrounding the real-time characterization of the F1 region by ARTIST. Therefore available DPS data from the archives of the Grahamstown station were re-scaled manually in order to establish the extent of the problem and the times and conditions under which most inaccuracies occur. The re-scaled data were used to update the F1 contribution of an existing NN based ionospheric model, the LAM model, which predicts the values of the parameters required to produce an electron density profile. This thesis describes the development of three separate NNs required to predict the ionospheric characteristics and coefficients that are required to describe the F1 layer profile. Inputs to the NNs include day number, hour and measures of solar and magnetic activity. Outputs include the value of the critical frequency of the F1 layer, foF1, the real height of reflection at the peak, hmFl, as well as information on the state of the F1 layer. All data from the Grahamstown station from 1973 to 2003 was used to train these NNs. Tests show that the predictive ability of the LAM model has been improved by incorporating the re-scaled data.
- Full Text:
- Date Issued: 2005
- Authors: Jacobs, Linda
- Date: 2005
- Subjects: Ionosphere , Ionospheric electron density -- South Africa -- Grahamstown , Neural networks (Computer Science)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5511 , http://hdl.handle.net/10962/d1008094 , Ionosphere , Ionospheric electron density -- South Africa -- Grahamstown , Neural networks (Computer Science)
- Description: This thesis describes an analysis of the F1 layer data obtained from the Grahamstown (33.32°S, 26.500 E), South Africa ionospheric station and the use of this data in improving a Neural Network (NN) based model of the F1 layer of the ionosphere. An application for real-time ray tracing through the South African ionosphere was identified, and for this application real-time evaluation of the electron density profile is essential. Raw real-time virtual height data are provided by a Lowell Digisonde (DPS), which employs the automatic scaling software, ARTIST whose output includes the virtual-toreal height data conversion. Experience has shown that there are times when the ray tracing performance is degraded because of difficulties surrounding the real-time characterization of the F1 region by ARTIST. Therefore available DPS data from the archives of the Grahamstown station were re-scaled manually in order to establish the extent of the problem and the times and conditions under which most inaccuracies occur. The re-scaled data were used to update the F1 contribution of an existing NN based ionospheric model, the LAM model, which predicts the values of the parameters required to produce an electron density profile. This thesis describes the development of three separate NNs required to predict the ionospheric characteristics and coefficients that are required to describe the F1 layer profile. Inputs to the NNs include day number, hour and measures of solar and magnetic activity. Outputs include the value of the critical frequency of the F1 layer, foF1, the real height of reflection at the peak, hmFl, as well as information on the state of the F1 layer. All data from the Grahamstown station from 1973 to 2003 was used to train these NNs. Tests show that the predictive ability of the LAM model has been improved by incorporating the re-scaled data.
- Full Text:
- Date Issued: 2005
The effect of personalised adjustments to computer workstations on the efficiency and physical comfort of computer operators
- Authors: James, Genevieve
- Date: 2005
- Subjects: Human engineering , Engineering design , Work environment , Microcomputer workstations -- Health aspects , Occupational diseases -- Prevention
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5112 , http://hdl.handle.net/10962/d1005190 , Human engineering , Engineering design , Work environment , Microcomputer workstations -- Health aspects , Occupational diseases -- Prevention
- Description: The present study sought to investigate the effects of a Standard workstation, designed for “average” users, on an anthropometrically diverse sample of computer operators, and to assess whether physical and perceptual responses, as well as performance efficiency were dependent on stature. Further investigation assessed the influence of personalised adjustments to the Standard workstation, based on the anthropometric characteristics of the subjects, as well as the introduction of a custom-designed ‘floating’ wrist support, on subject responses. All subjects (n=30) were tested in each of the three workstations: Standard, Personalised and Wrist Support. For analysis of responses in the Standard workstation, subjects were divided into three groups depending on their stature: Short (<1650mm), Medium (1650mm to 1800mm), Tall (>1800mm). The musculoskeletal responses indicated that Tall subjects were forced to adopt the most awkward general body postures as a result of the low computer screen. However, the low screen allowed for the Short subjects to adopt the most natural general body postures, although levels of muscular activity in the upper trapezius suggest that the muscular load imposed on both Short and Tall subjects was significantly greater than that imposed on the Medium subjects. In addition, the Medium subjects’ perceptions of the Standard workstation dimensions support the fact that this workstation was better suited to users with “average” morphologies. The responses elicited in the Personalised and Wrist Support workstations were improved significantly when compared to the Standard workstation. Joint angles were more natural, upper trapezius EMG was reduced, standard of performance improved and perceptual responses indicated a diminished incidence of body and visual discomfort, as well as greater perceived satisfaction with these workstation dimensions. The improved physical responses suggest a decrease in the risk of developing cumulative trauma disorders. Although subjects were unaccustomed to the wrist support device, this workstation demonstrated a further reduction in the range of wrist angles, as well as a general positive attitude towards the concept.
- Full Text:
- Date Issued: 2005
- Authors: James, Genevieve
- Date: 2005
- Subjects: Human engineering , Engineering design , Work environment , Microcomputer workstations -- Health aspects , Occupational diseases -- Prevention
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5112 , http://hdl.handle.net/10962/d1005190 , Human engineering , Engineering design , Work environment , Microcomputer workstations -- Health aspects , Occupational diseases -- Prevention
- Description: The present study sought to investigate the effects of a Standard workstation, designed for “average” users, on an anthropometrically diverse sample of computer operators, and to assess whether physical and perceptual responses, as well as performance efficiency were dependent on stature. Further investigation assessed the influence of personalised adjustments to the Standard workstation, based on the anthropometric characteristics of the subjects, as well as the introduction of a custom-designed ‘floating’ wrist support, on subject responses. All subjects (n=30) were tested in each of the three workstations: Standard, Personalised and Wrist Support. For analysis of responses in the Standard workstation, subjects were divided into three groups depending on their stature: Short (<1650mm), Medium (1650mm to 1800mm), Tall (>1800mm). The musculoskeletal responses indicated that Tall subjects were forced to adopt the most awkward general body postures as a result of the low computer screen. However, the low screen allowed for the Short subjects to adopt the most natural general body postures, although levels of muscular activity in the upper trapezius suggest that the muscular load imposed on both Short and Tall subjects was significantly greater than that imposed on the Medium subjects. In addition, the Medium subjects’ perceptions of the Standard workstation dimensions support the fact that this workstation was better suited to users with “average” morphologies. The responses elicited in the Personalised and Wrist Support workstations were improved significantly when compared to the Standard workstation. Joint angles were more natural, upper trapezius EMG was reduced, standard of performance improved and perceptual responses indicated a diminished incidence of body and visual discomfort, as well as greater perceived satisfaction with these workstation dimensions. The improved physical responses suggest a decrease in the risk of developing cumulative trauma disorders. Although subjects were unaccustomed to the wrist support device, this workstation demonstrated a further reduction in the range of wrist angles, as well as a general positive attitude towards the concept.
- Full Text:
- Date Issued: 2005
On the growth and characterisation of AIGaN alloys for optoelectronic applications
- Authors: James, Grant Robert
- Date: 2005
- Subjects: Gallium nitride -- Electric properties , Photoluminescence
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/8824 , vital:26433
- Description: In this study the growth and characterisation of undoped and Si-doped AlxGa1-xN has been performed. The layers were grown using low-pressure metalorganic vapour phase deposition (MOCVD) on sapphire substrates. The optical and electrical properties of the AlxGa1-xN layers were studied using variable temperature Hall effect and photoluminescence measurements. AlxGa1-xN layers were grown over the entire composition range. Room temperature ultraviolet (UV) transmission measurements showed that the material quality was very good for layers with an Al content, x, of 0 _ x _ 0.5. However, the quality of layers of higher composition was seen to rapidly decrease with increasing x. The electrical and optical properties of AlxGa1-xN with x < 0.5 were also good, comparable to those reported on in literature. The study of the Si-doping of AlxGa1-xN was performed in two parts; firstly a series of Al0.23Ga0.77N samples was grown in which the doping level was increased from zero to n _ 3 × 1018 cm-3. A similar, albeit a less rigorous, study was performed for Al0.41Ga0.59N and Al0.5Ga0.5N. A second series of samples was then grown in which the doping level was kept constant, while the Al content was incrementally increased. Room temperature Hall effect measurements performed on Si-doped Al0.23Ga0.77N showed that the electron concentration did not scale linearly with the silane flow, as was the case in GaN. It was also seen that the electron mobility of the layers increased with slight Si-doping, possibly due to an improvement in the crystalline quality and/or a change in the conduction mechanism. It was also found that at higher compositions (x = 0.41 and 0.50) an increase in the doping level resulted in an increase in the mobility. Variable temperature Hall effect and photoluminescence measurements, performed on the Al0.23Ga0.77N samples, revealed a good correlation between the first PL activation energy E1 and the donor activation energy ED, prompting the conclusion that the first PL recombination channel in AlxGa1-xN is due to the delocalisation of excitons bound at neutral Si donors. Furthermore, E1 and ED were seen to decrease with n1/3, as is the case for GaN and other semiconductor materials. It was also observed that strong exciton localisation occurs in slightly Si-doped material, with the amount of localization becoming less at higher doping levels. Possible mechanisms responsible for the second PL recombination channel of activation energy E2 were also proposed. The electrical and optical properties of the second set of AlxGa1-xN samples was then studied. The PL properties of undoped AlxGa1-xN were typical of a homogeneous alloy system, with the increase in the PL FWHM and exciton localisation energies with x following the trend predicted by alloy disorder theory. The variation of the band gap energy with the Al content could not, however, be fitted over the entire composition range using a single bowing parameter. It was proposed that this was due either to an effect of the 9 7 valence band crossover, or due to exciton localisation at alloy disorder and/or impurities. As was the case for GaN and Al0.23Ga0.77N, all undoped material was highly resistive. As was mentioned earlier, the exciton localisation energies increased according to alloy disorder theory in undoped AlxGa1-xN. In the doped samples, however, a large increase in the donor localisation energy was measured for x > 0.3. The possibility that Si could become a DX-centre in AlxGa1-xN was then investigated. However, Hall effect measurements showed that the Si activation energy increased in good agreement with the model of a shallow effective mass state donor, with no sudden increase in ED being observed up to x = 0.4. It was then suggested that the increase in the E1 and E2 activation energies, as well as the exciton localisation energies, could be due to the 9 7 valence band crossover, which occurs at roughly the same composition. However, due to the scarcity of reports on the valence band structure in AlxGa1-xN no conclusions could be made at this stage as to the effect of the 9 7 valence band crossover on the PL properties of AlxGa1-xN.
- Full Text:
- Date Issued: 2005
- Authors: James, Grant Robert
- Date: 2005
- Subjects: Gallium nitride -- Electric properties , Photoluminescence
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/8824 , vital:26433
- Description: In this study the growth and characterisation of undoped and Si-doped AlxGa1-xN has been performed. The layers were grown using low-pressure metalorganic vapour phase deposition (MOCVD) on sapphire substrates. The optical and electrical properties of the AlxGa1-xN layers were studied using variable temperature Hall effect and photoluminescence measurements. AlxGa1-xN layers were grown over the entire composition range. Room temperature ultraviolet (UV) transmission measurements showed that the material quality was very good for layers with an Al content, x, of 0 _ x _ 0.5. However, the quality of layers of higher composition was seen to rapidly decrease with increasing x. The electrical and optical properties of AlxGa1-xN with x < 0.5 were also good, comparable to those reported on in literature. The study of the Si-doping of AlxGa1-xN was performed in two parts; firstly a series of Al0.23Ga0.77N samples was grown in which the doping level was increased from zero to n _ 3 × 1018 cm-3. A similar, albeit a less rigorous, study was performed for Al0.41Ga0.59N and Al0.5Ga0.5N. A second series of samples was then grown in which the doping level was kept constant, while the Al content was incrementally increased. Room temperature Hall effect measurements performed on Si-doped Al0.23Ga0.77N showed that the electron concentration did not scale linearly with the silane flow, as was the case in GaN. It was also seen that the electron mobility of the layers increased with slight Si-doping, possibly due to an improvement in the crystalline quality and/or a change in the conduction mechanism. It was also found that at higher compositions (x = 0.41 and 0.50) an increase in the doping level resulted in an increase in the mobility. Variable temperature Hall effect and photoluminescence measurements, performed on the Al0.23Ga0.77N samples, revealed a good correlation between the first PL activation energy E1 and the donor activation energy ED, prompting the conclusion that the first PL recombination channel in AlxGa1-xN is due to the delocalisation of excitons bound at neutral Si donors. Furthermore, E1 and ED were seen to decrease with n1/3, as is the case for GaN and other semiconductor materials. It was also observed that strong exciton localisation occurs in slightly Si-doped material, with the amount of localization becoming less at higher doping levels. Possible mechanisms responsible for the second PL recombination channel of activation energy E2 were also proposed. The electrical and optical properties of the second set of AlxGa1-xN samples was then studied. The PL properties of undoped AlxGa1-xN were typical of a homogeneous alloy system, with the increase in the PL FWHM and exciton localisation energies with x following the trend predicted by alloy disorder theory. The variation of the band gap energy with the Al content could not, however, be fitted over the entire composition range using a single bowing parameter. It was proposed that this was due either to an effect of the 9 7 valence band crossover, or due to exciton localisation at alloy disorder and/or impurities. As was the case for GaN and Al0.23Ga0.77N, all undoped material was highly resistive. As was mentioned earlier, the exciton localisation energies increased according to alloy disorder theory in undoped AlxGa1-xN. In the doped samples, however, a large increase in the donor localisation energy was measured for x > 0.3. The possibility that Si could become a DX-centre in AlxGa1-xN was then investigated. However, Hall effect measurements showed that the Si activation energy increased in good agreement with the model of a shallow effective mass state donor, with no sudden increase in ED being observed up to x = 0.4. It was then suggested that the increase in the E1 and E2 activation energies, as well as the exciton localisation energies, could be due to the 9 7 valence band crossover, which occurs at roughly the same composition. However, due to the scarcity of reports on the valence band structure in AlxGa1-xN no conclusions could be made at this stage as to the effect of the 9 7 valence band crossover on the PL properties of AlxGa1-xN.
- Full Text:
- Date Issued: 2005
An investigation of female leaders' perceptions of organisational culture and leadership in a Catholic High School
- Jean-Louis, Lily-Claire Virginie
- Authors: Jean-Louis, Lily-Claire Virginie
- Date: 2005
- Subjects: Catholic schools -- South Africa -- Administration School management and organization -- South Africa Educational leadership -- South Africa Corporate culture -- South Africa Women school administrators -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1625 , http://hdl.handle.net/10962/d1003507
- Description: For the past thirty years, leadership theories have focused on the importance of the individual within the school organisation. The shared assumptions and beliefs of the individuals working in the same organisation shape the school’s organisational culture, and organisational culture is a salient factor which should be considered when understanding educational leadership. The focus of my study is to explore the relationship between organisational culture and leadership. In the same context, new approaches to the study of leadership have explored the issue of gender in leadership. Female leadership studies - the second focus of this study - seek not only to restore the place of the individual but also argue a place for women in educational leadership. Based in the interpretive paradigm, this is a case study of a Catholic all-girl secondary school called the Loreto Convent School of Pretoria. Historically, the Loreto schools have aimed at promoting and empowering girls’ education and female leadership. It was therefore an appropriate site in which to explore organisational culture and its relationship with leadership, particularly female leadership. I purposefully chose three of the school’s female leaders - the school’s principal, the High school Head of Department and the High school head girl - focusing on their perceptions and experiences of their leadership and the school’s culture. My research findings show that an understanding of the relationship between organisational culture and leadership cannot be complete without acknowledging the importance of the leader as an individual, with his/her personal background and values, taking into account gender as well as the multiple roles that the individual has in society. Furthermore, the ‘humane’ characteristic of educational leadership leads to an understanding that the leader is often confronted with conflicting situations where he/she is caught between personal/organisational values and the need to achieve the task. Finally, my findings show that contemporary leaders are now called upon to work and participate in the promotion of social justice in order to fight against society’s socio-economic inequality and improve the quality of education and life.
- Full Text:
- Date Issued: 2005
- Authors: Jean-Louis, Lily-Claire Virginie
- Date: 2005
- Subjects: Catholic schools -- South Africa -- Administration School management and organization -- South Africa Educational leadership -- South Africa Corporate culture -- South Africa Women school administrators -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1625 , http://hdl.handle.net/10962/d1003507
- Description: For the past thirty years, leadership theories have focused on the importance of the individual within the school organisation. The shared assumptions and beliefs of the individuals working in the same organisation shape the school’s organisational culture, and organisational culture is a salient factor which should be considered when understanding educational leadership. The focus of my study is to explore the relationship between organisational culture and leadership. In the same context, new approaches to the study of leadership have explored the issue of gender in leadership. Female leadership studies - the second focus of this study - seek not only to restore the place of the individual but also argue a place for women in educational leadership. Based in the interpretive paradigm, this is a case study of a Catholic all-girl secondary school called the Loreto Convent School of Pretoria. Historically, the Loreto schools have aimed at promoting and empowering girls’ education and female leadership. It was therefore an appropriate site in which to explore organisational culture and its relationship with leadership, particularly female leadership. I purposefully chose three of the school’s female leaders - the school’s principal, the High school Head of Department and the High school head girl - focusing on their perceptions and experiences of their leadership and the school’s culture. My research findings show that an understanding of the relationship between organisational culture and leadership cannot be complete without acknowledging the importance of the leader as an individual, with his/her personal background and values, taking into account gender as well as the multiple roles that the individual has in society. Furthermore, the ‘humane’ characteristic of educational leadership leads to an understanding that the leader is often confronted with conflicting situations where he/she is caught between personal/organisational values and the need to achieve the task. Finally, my findings show that contemporary leaders are now called upon to work and participate in the promotion of social justice in order to fight against society’s socio-economic inequality and improve the quality of education and life.
- Full Text:
- Date Issued: 2005
Understanding editorial independence and public accountability issues in public broadcasting service: a study of the editorial policies at the South African Broadcasting Corporation (SABC)
- Authors: Jjuuko, Denis Charles
- Date: 2005
- Subjects: South African Broadcasting Corporation , South African Broadcasting Corporation -- Law and legislation , Broadcasting -- Social aspects -- South Africa , Mass media -- Social aspects -- South Africa , Broadcasting policy -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3437 , http://hdl.handle.net/10962/d1002891 , South African Broadcasting Corporation , South African Broadcasting Corporation -- Law and legislation , Broadcasting -- Social aspects -- South Africa , Mass media -- Social aspects -- South Africa , Broadcasting policy -- South Africa
- Description: The concepts of editorial independence and public accountability are necessary in public broadcasting service as they help make a distinction between a public service broadcaster, a government and a commercial service broadcaster. This is because public service broadcasters are tasked with the responsibility of serving the interests of the general public. To do this, the above mentioned concepts have to be in place. This study examines these issues (editorial independence and public accountability) with reference to a case study of the editorial policies of the South African Broadcasting Corporation (SABC). Using public broadcasting theory, policy theory and qualitative research methods, the study examines the genesis of these editorial policies in 2003/2004 and how they provide the SABC with a means of balancing the tensions of editorial independence and public accountability. In analysing the SABC’s editorial policies, the study deals only with those policies whose principles are directly related to editorial independence and public accountability. Although some of these policies are found to be in line with public broadcasting service trends, others are found lacking. Various recommendations are made. The case study demonstrates the importance of an integrated and elaborated policy perspective in setting out how a public service broadcaster can manage editorial independence and public accountability. It also highlights the importance of using international ‘role models’ in ways that are appropriately adapted for the specific country concerned.
- Full Text:
- Date Issued: 2005
- Authors: Jjuuko, Denis Charles
- Date: 2005
- Subjects: South African Broadcasting Corporation , South African Broadcasting Corporation -- Law and legislation , Broadcasting -- Social aspects -- South Africa , Mass media -- Social aspects -- South Africa , Broadcasting policy -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3437 , http://hdl.handle.net/10962/d1002891 , South African Broadcasting Corporation , South African Broadcasting Corporation -- Law and legislation , Broadcasting -- Social aspects -- South Africa , Mass media -- Social aspects -- South Africa , Broadcasting policy -- South Africa
- Description: The concepts of editorial independence and public accountability are necessary in public broadcasting service as they help make a distinction between a public service broadcaster, a government and a commercial service broadcaster. This is because public service broadcasters are tasked with the responsibility of serving the interests of the general public. To do this, the above mentioned concepts have to be in place. This study examines these issues (editorial independence and public accountability) with reference to a case study of the editorial policies of the South African Broadcasting Corporation (SABC). Using public broadcasting theory, policy theory and qualitative research methods, the study examines the genesis of these editorial policies in 2003/2004 and how they provide the SABC with a means of balancing the tensions of editorial independence and public accountability. In analysing the SABC’s editorial policies, the study deals only with those policies whose principles are directly related to editorial independence and public accountability. Although some of these policies are found to be in line with public broadcasting service trends, others are found lacking. Various recommendations are made. The case study demonstrates the importance of an integrated and elaborated policy perspective in setting out how a public service broadcaster can manage editorial independence and public accountability. It also highlights the importance of using international ‘role models’ in ways that are appropriately adapted for the specific country concerned.
- Full Text:
- Date Issued: 2005
The market overview and strategy development for selected components of a marketing plan for a cellular provider
- Authors: Jones, Frank Harold
- Date: 2005
- Subjects: Cell phone services industry -- South Africa -- Marketing , Marketing -- Planning
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:10924 , http://hdl.handle.net/10948/175 , Cell phone services industry -- South Africa -- Marketing , Marketing -- Planning
- Description: The research problem addressed in this study was to develop a marketing plan consisting of selected elements that would give a cellular company like Vodacom a competitive advantage over competitors and to capture a significant market share when marketing mobile data services like 3G. To achieve this object, a literature study to determine the key components of a marketing plan was undertaken and a theoretical model was selected to develop a marketing plan of selected components In addition to the literature study, an empirical study was conducted to identify core concepts critical to the development of a selected element marketing plan to market 3G and re-launch mobile data services. The results of the literature study were combined with the empirical study and a marketing plan based on McDonald was developed. Michael Porter’s five forces model was used as a reference to discuss the competitor analysis, a marketing strategy was compiled with specific referencing to the four P’s of marketing and marketing controls formed the basis of this research. This study concludes with recommendations applicable for the implementation of the marketing plan and options for further research.
- Full Text:
- Date Issued: 2005
- Authors: Jones, Frank Harold
- Date: 2005
- Subjects: Cell phone services industry -- South Africa -- Marketing , Marketing -- Planning
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:10924 , http://hdl.handle.net/10948/175 , Cell phone services industry -- South Africa -- Marketing , Marketing -- Planning
- Description: The research problem addressed in this study was to develop a marketing plan consisting of selected elements that would give a cellular company like Vodacom a competitive advantage over competitors and to capture a significant market share when marketing mobile data services like 3G. To achieve this object, a literature study to determine the key components of a marketing plan was undertaken and a theoretical model was selected to develop a marketing plan of selected components In addition to the literature study, an empirical study was conducted to identify core concepts critical to the development of a selected element marketing plan to market 3G and re-launch mobile data services. The results of the literature study were combined with the empirical study and a marketing plan based on McDonald was developed. Michael Porter’s five forces model was used as a reference to discuss the competitor analysis, a marketing strategy was compiled with specific referencing to the four P’s of marketing and marketing controls formed the basis of this research. This study concludes with recommendations applicable for the implementation of the marketing plan and options for further research.
- Full Text:
- Date Issued: 2005
Isolation and characterization of a novel thermostable and catalytically efficient laccase from Peniophora sp. strain UD4
- Authors: Jordaan, Justin
- Date: 2005
- Subjects: Enzymes Enzymes -- Industrial applications Peniophora Laccase
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3970 , http://hdl.handle.net/10962/d1004029
- Description: Enzymes are becoming an effective tool in industrial processes, from crude applications such as bioremediation to fine processes such as chirally selective biocatalysis. The ligninolytic enzymes have recently received considerable attention for industrial application due to both their broad substrate range and their ability to degrade the most recalcitrant natural polymer, lignin. This group of enzymes was therefore identified as the target group for this study. Improved enzyme properties are constantly being sought to enhance the range of applications for enzymes. Biodiversity provides a wide variety of enzymes. Several researchers have concentrated on extremophiles as their primary source of superior enzymes, consequently neglecting temperate environments in their search for these enzymes. The relatively neglected fungal biodiversity of South Africa provided an opportunity to test the hypothesis that potentially important industrial enzymes with unusual properties could be isolated from mesophilic basidiomycetous fungi. Subsequent screening of Eastern Cape biodiversity for thermostable ligninolytic enzymes from basidiomycetes resulted in the isolation of a novel laccase enzyme from a basidiomycetous species. This fungus was identified as Peniophora sp. UD4 by phylogenetic analysis of rDNA ITS sequences. Initial studies indicated a superior optimum temperature of 70°C and thermostability, indicated by no loss in activity at 60°C over nine hours. Further characterization of the laccase revealed a broader than usual substrate range through its unusual ability to oxidatively couple DMAB and MBTH. The laccase also exhibited a broad pH oxidation range for ABTS (pH 2 – 6.8), and a relatively high affinity (K_m_ = 0.0123 mM) and catalytic efficiency (63 252 mM^(-1)^s^(-1)^) for ABTS as a substrate. The laccase activity from Peniophora sp. UD4 was shown to be comprised of three isozymes with a molecular weight of 62 kDa and pI’s of 6.33, 6.45 and 6.50. Investigation of the nutrient and physical factors affecting ligninolytic enzyme production and growth of Peniophora sp. UD4 indicated that the wild-type organism was unsuitable for large scale production of the thermostable laccase due to the low levels of laccase production. The thermostable laccase was applied to defouling of ultrafiltration membranes, bioremediation of industrial waste streams, biocatalysis, and biosensor technology as potential applications. Application of the Peniophora sp. UD4 laccase to defouling of membranes used for ultrafiltration of brown water showed large flux recoveries of 31, 21 and 21% after the first three defouling recycles respectively, compared to 3% for the control without immobilized enzyme. The novel laccase showed potential for the bioremediation of industrial waste streams, the most successful being that of bleach plant effluent, where a reduction of 66% of the phenolic load was achieved. Application of the novel laccase to biocatalytic oxidation of ferulic acid and (±)-α-pinene showed higher product yield as compared to oxidation of these compounds by Trametes versicolor laccase in mediated and non-mediated systems. The major products of (±)-α-pinene oxidation were identified as verbenol and trans-sorberol. The Peniophora sp. UD4 laccase was successfully applied to biosensor technology, which benchmarked significantly better than Trametes versicolor laccase for the detection of 4-chlorophenol. The biosensor developed with laccase from UD4 by covalent binding to a glassy carbon electrode exhibited the best combination of sensitivity and stability. This thesis shows that a laccase with superior properties was obtained from a mesophilic South African basidiomycete. The catalytic properties displayed by the novel laccase from Peniophora sp. UD4 all contribute to the increased industrial applicability of laccases, and may be the most industrially feasible enzyme of its class isolated to date.
- Full Text:
- Date Issued: 2005
- Authors: Jordaan, Justin
- Date: 2005
- Subjects: Enzymes Enzymes -- Industrial applications Peniophora Laccase
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3970 , http://hdl.handle.net/10962/d1004029
- Description: Enzymes are becoming an effective tool in industrial processes, from crude applications such as bioremediation to fine processes such as chirally selective biocatalysis. The ligninolytic enzymes have recently received considerable attention for industrial application due to both their broad substrate range and their ability to degrade the most recalcitrant natural polymer, lignin. This group of enzymes was therefore identified as the target group for this study. Improved enzyme properties are constantly being sought to enhance the range of applications for enzymes. Biodiversity provides a wide variety of enzymes. Several researchers have concentrated on extremophiles as their primary source of superior enzymes, consequently neglecting temperate environments in their search for these enzymes. The relatively neglected fungal biodiversity of South Africa provided an opportunity to test the hypothesis that potentially important industrial enzymes with unusual properties could be isolated from mesophilic basidiomycetous fungi. Subsequent screening of Eastern Cape biodiversity for thermostable ligninolytic enzymes from basidiomycetes resulted in the isolation of a novel laccase enzyme from a basidiomycetous species. This fungus was identified as Peniophora sp. UD4 by phylogenetic analysis of rDNA ITS sequences. Initial studies indicated a superior optimum temperature of 70°C and thermostability, indicated by no loss in activity at 60°C over nine hours. Further characterization of the laccase revealed a broader than usual substrate range through its unusual ability to oxidatively couple DMAB and MBTH. The laccase also exhibited a broad pH oxidation range for ABTS (pH 2 – 6.8), and a relatively high affinity (K_m_ = 0.0123 mM) and catalytic efficiency (63 252 mM^(-1)^s^(-1)^) for ABTS as a substrate. The laccase activity from Peniophora sp. UD4 was shown to be comprised of three isozymes with a molecular weight of 62 kDa and pI’s of 6.33, 6.45 and 6.50. Investigation of the nutrient and physical factors affecting ligninolytic enzyme production and growth of Peniophora sp. UD4 indicated that the wild-type organism was unsuitable for large scale production of the thermostable laccase due to the low levels of laccase production. The thermostable laccase was applied to defouling of ultrafiltration membranes, bioremediation of industrial waste streams, biocatalysis, and biosensor technology as potential applications. Application of the Peniophora sp. UD4 laccase to defouling of membranes used for ultrafiltration of brown water showed large flux recoveries of 31, 21 and 21% after the first three defouling recycles respectively, compared to 3% for the control without immobilized enzyme. The novel laccase showed potential for the bioremediation of industrial waste streams, the most successful being that of bleach plant effluent, where a reduction of 66% of the phenolic load was achieved. Application of the novel laccase to biocatalytic oxidation of ferulic acid and (±)-α-pinene showed higher product yield as compared to oxidation of these compounds by Trametes versicolor laccase in mediated and non-mediated systems. The major products of (±)-α-pinene oxidation were identified as verbenol and trans-sorberol. The Peniophora sp. UD4 laccase was successfully applied to biosensor technology, which benchmarked significantly better than Trametes versicolor laccase for the detection of 4-chlorophenol. The biosensor developed with laccase from UD4 by covalent binding to a glassy carbon electrode exhibited the best combination of sensitivity and stability. This thesis shows that a laccase with superior properties was obtained from a mesophilic South African basidiomycete. The catalytic properties displayed by the novel laccase from Peniophora sp. UD4 all contribute to the increased industrial applicability of laccases, and may be the most industrially feasible enzyme of its class isolated to date.
- Full Text:
- Date Issued: 2005
An investigation of specific contributing factors affecting quality assurance in the diagnosis of conventional cervical smears
- Authors: Jordaan, Suzette Mirietta
- Date: 2005
- Subjects: Cervix uteri -- Cancer -- Cytodiagnosis -- Quality control , Vaginal smears -- Quality control , Pap test -- Quality control
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10117 , http://hdl.handle.net/10948/173 , Cervix uteri -- Cancer -- Cytodiagnosis -- Quality control , Vaginal smears -- Quality control , Pap test -- Quality control
- Description: The purpose of this study is to investigate specific contributing factors affecting quality assurance in the diagnosis of conventional cervical smears. More than half of South- African women fail to have one cervical smear in their lifetime and +/- 50 percent of those who do have cervical smears taken, are lost to follow-up. Since cervical cancer is the most common malignancy amongst women in developing countries, the medical profession will have to endeavor to screen a higher rate of women and ensure a 100 percent quality assurance with every patient treated in order to reduce the unacceptable high incidence of cervical carcinoma. At this stage it seems like an impossible task to screen all women in South Africa, due to far-off rural areas, shortage of medical professionals and the lack of knowledge of some women of the necessity of cervical smears. Many newly qualified South-African doctors leave the country to go and work elsewhere. South Africa then in turn has to recruit doctors from other countries to staff the State hospitals and clinics. Some areas have one doctor to thousands of patients, insufficient nursing personnel and inadequate equipment. Doctors in some areas cannot cope with the volume of work and the long hours. One has to accept that the quality of the management of some patients is affected negatively. There are a number of medico-legal issues (world wide) in relation to aspects of cervical cancer prevention practices which are controversial and are of particular concern to all of those involved in cervical cancer prevention. Various countries have therefore formed different national organizations to address the medico-legal issues in screening for the prevention of cancer. These organizations monitors procedures, internal quality control as well as external quality control. In South Africa, medico-legal cases are not so prevalent, but may become so shortly. The South-African medical professionals therefore have to ensure that their quality of work conforms to accepted good practice in all circumstances. State hospitals serve thousands of patients per month and it is an every day occurrence to see long queues of patients sitting waiting for doctors and who often have to come back the following day. The situation appears to be much improved in private practice and since patients have medical cover and accessible medical facilities. Since cervical cancer is the most common malignancy amongst women in developing countries, the medical profession will have to endeavor to screen a higher rate of women and ensure a 100 percent quality assurance with every patient treated in order to reduce the unacceptable high incidence of cervical carcinoma. At this stage it seems like an impossible task to screen 100 percent of women in South Africa, due to far-off rural areas, the shortage of medical professionals and ignorance of patients. Quality assurance is therefore of paramount importance to every medical professional for every patient treated. Laboratories all worldwide have been, or are in the process of being accredited by their specific accreditation authorities. The main reason for this is improvement of quality control and therefore quality assurance. The South African National Accreditation Society (SANAS) now accredits various laboratories in South Africa with the view of accreditting all laboratories within a certain time limit. The Ampath laboratory Port Elizabeth was successfully accredited during 2001. Accredited laboratories have to uphold a very high degree of quality to remain accredited. A team of professionals inspects the laboratory every 2 years and other quality assurance staff inspects the laboratories every few months. All aspects of the laboratory are checked, e.g. the qualification of staff, their registration with the Health Professions Council of South Africa (HPCSA), their curriculum vitaes, equipment, safety of the laboratory etc. Since the laboratory chosen for this study, is accredited, the author evaluated every cervical smear that was received in the laboratory since the year 2000, with the following objectives in mind: · Whether the presence or absence of an endocervical component has an effect on the adequacy of cervical smears · To determine the effect of using smaller coverslips on quality assurance in the cytology laboratory · Evaluate the effect that manual re-screening of smears has on quality assurance in the cytology laboratory. As there is a shortage of cytotechnologists and pathologists worldwide, several countries make use of automated screening devices as primary screening or secondary screening for quality assurance. These devices were tested in some laboratories in South Africa but were found to be very expensive and sensitivity and specificity were not up to standard. Sensitivity is a measure of the ability of a test to detect the abnormal - Sensitivity is the ratio of true positives to true positives + false negatives. Specificity is a measure of the ability of a test to correctly identify the negative - Specificity is the ratio of true negative to true negatives + false positives. The automated screening machines failed to identify abnormal cells amongst inflammatory cells, as well as in very blood stained smears. Several other problems also occurred and an increasing number of smears had to be manually rescreened, thus making this exercise costly and not helpful as a quality assurance instrument. The slides used for this thesis, have been retrieved from the archives of the Ampath laboratory in Port Elizabeth. Fourteen specific contributing factors affecting quality assurance in the diagnosis of cervical smears are also discussed and conclusions and recommendations given.
- Full Text:
- Date Issued: 2005
- Authors: Jordaan, Suzette Mirietta
- Date: 2005
- Subjects: Cervix uteri -- Cancer -- Cytodiagnosis -- Quality control , Vaginal smears -- Quality control , Pap test -- Quality control
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10117 , http://hdl.handle.net/10948/173 , Cervix uteri -- Cancer -- Cytodiagnosis -- Quality control , Vaginal smears -- Quality control , Pap test -- Quality control
- Description: The purpose of this study is to investigate specific contributing factors affecting quality assurance in the diagnosis of conventional cervical smears. More than half of South- African women fail to have one cervical smear in their lifetime and +/- 50 percent of those who do have cervical smears taken, are lost to follow-up. Since cervical cancer is the most common malignancy amongst women in developing countries, the medical profession will have to endeavor to screen a higher rate of women and ensure a 100 percent quality assurance with every patient treated in order to reduce the unacceptable high incidence of cervical carcinoma. At this stage it seems like an impossible task to screen all women in South Africa, due to far-off rural areas, shortage of medical professionals and the lack of knowledge of some women of the necessity of cervical smears. Many newly qualified South-African doctors leave the country to go and work elsewhere. South Africa then in turn has to recruit doctors from other countries to staff the State hospitals and clinics. Some areas have one doctor to thousands of patients, insufficient nursing personnel and inadequate equipment. Doctors in some areas cannot cope with the volume of work and the long hours. One has to accept that the quality of the management of some patients is affected negatively. There are a number of medico-legal issues (world wide) in relation to aspects of cervical cancer prevention practices which are controversial and are of particular concern to all of those involved in cervical cancer prevention. Various countries have therefore formed different national organizations to address the medico-legal issues in screening for the prevention of cancer. These organizations monitors procedures, internal quality control as well as external quality control. In South Africa, medico-legal cases are not so prevalent, but may become so shortly. The South-African medical professionals therefore have to ensure that their quality of work conforms to accepted good practice in all circumstances. State hospitals serve thousands of patients per month and it is an every day occurrence to see long queues of patients sitting waiting for doctors and who often have to come back the following day. The situation appears to be much improved in private practice and since patients have medical cover and accessible medical facilities. Since cervical cancer is the most common malignancy amongst women in developing countries, the medical profession will have to endeavor to screen a higher rate of women and ensure a 100 percent quality assurance with every patient treated in order to reduce the unacceptable high incidence of cervical carcinoma. At this stage it seems like an impossible task to screen 100 percent of women in South Africa, due to far-off rural areas, the shortage of medical professionals and ignorance of patients. Quality assurance is therefore of paramount importance to every medical professional for every patient treated. Laboratories all worldwide have been, or are in the process of being accredited by their specific accreditation authorities. The main reason for this is improvement of quality control and therefore quality assurance. The South African National Accreditation Society (SANAS) now accredits various laboratories in South Africa with the view of accreditting all laboratories within a certain time limit. The Ampath laboratory Port Elizabeth was successfully accredited during 2001. Accredited laboratories have to uphold a very high degree of quality to remain accredited. A team of professionals inspects the laboratory every 2 years and other quality assurance staff inspects the laboratories every few months. All aspects of the laboratory are checked, e.g. the qualification of staff, their registration with the Health Professions Council of South Africa (HPCSA), their curriculum vitaes, equipment, safety of the laboratory etc. Since the laboratory chosen for this study, is accredited, the author evaluated every cervical smear that was received in the laboratory since the year 2000, with the following objectives in mind: · Whether the presence or absence of an endocervical component has an effect on the adequacy of cervical smears · To determine the effect of using smaller coverslips on quality assurance in the cytology laboratory · Evaluate the effect that manual re-screening of smears has on quality assurance in the cytology laboratory. As there is a shortage of cytotechnologists and pathologists worldwide, several countries make use of automated screening devices as primary screening or secondary screening for quality assurance. These devices were tested in some laboratories in South Africa but were found to be very expensive and sensitivity and specificity were not up to standard. Sensitivity is a measure of the ability of a test to detect the abnormal - Sensitivity is the ratio of true positives to true positives + false negatives. Specificity is a measure of the ability of a test to correctly identify the negative - Specificity is the ratio of true negative to true negatives + false positives. The automated screening machines failed to identify abnormal cells amongst inflammatory cells, as well as in very blood stained smears. Several other problems also occurred and an increasing number of smears had to be manually rescreened, thus making this exercise costly and not helpful as a quality assurance instrument. The slides used for this thesis, have been retrieved from the archives of the Ampath laboratory in Port Elizabeth. Fourteen specific contributing factors affecting quality assurance in the diagnosis of cervical smears are also discussed and conclusions and recommendations given.
- Full Text:
- Date Issued: 2005
Consolidating democracy, building civil society : the South African Council of Churches in post-apartheid South Africa and its policy of critical solidarity with the state
- Authors: Joseph, Stacey-Leigh
- Date: 2005
- Subjects: South African Council of Churches Church and state -- South Africa Christianity and politics -- South Africa Apartheid -- Religious aspects -- South Africa AIDS (Disease) -- Government policy -- South Africa Debts, External -- South Africa South Africa -- Foreign relations -- Zimbabwe South Africa -- Politics and government -- 1994
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:2874 , http://hdl.handle.net/10962/d1007957
- Description: The South African Council of Churches (SACC) played an extremely crucial role during the struggle against apartheid. The role of the SACC was first and foremost to provide a voice for the voiceless. It managed, among other tasks, to actively fill the void left by movements banned by the illegitimate apartheid government. As a result of its fight against the inequalities that existed in South Africa, its work adopted a political character. In the aftermath of post-apartheid South Africa, the SACC was left with the task of redefining its role within South African society and civil society, specifically. The euphoric sentiment in the mid-1990s was in part reflected in the SACC. However, the conclusion reached by the Council in 1995 was that it would also play a role of 'critical solidarity' which essentially meant that it would not shy away from attacking the government when the need arose. Since 1994, the South African government has implemented a number of policies that do not appear to be in the immediate interest of the majority of South African citizens atld have brought church and state into conflict. This thesis attempts to tackle three issues which are pertinent to the South African situation and which shed light on state-civil society interactions. These issues are HIV I Aids, the question of odious debt and the Zimbabwe crisis. By using both primary and secondary sources, the SACC's responses to government's handling of these matters will be compared with the responses of the South African Catholic Bishops Conference in order to determine their relationships with government. The conclusion of this investigation is that the SACC has in fact managed to maintain a position of critical solidarity. It has been faced with numerous challenges with regard to maintaining the fragile boundary of alliance with government on the one hand, and becoming anti-government on the other. However, by forming alliances with other civil society actors as well as fostering a relationship with government in order to facilitate mediation this dissertation argues that the SACC has become an essential member of South Africa's vibrant civil society.
- Full Text:
- Date Issued: 2005
- Authors: Joseph, Stacey-Leigh
- Date: 2005
- Subjects: South African Council of Churches Church and state -- South Africa Christianity and politics -- South Africa Apartheid -- Religious aspects -- South Africa AIDS (Disease) -- Government policy -- South Africa Debts, External -- South Africa South Africa -- Foreign relations -- Zimbabwe South Africa -- Politics and government -- 1994
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:2874 , http://hdl.handle.net/10962/d1007957
- Description: The South African Council of Churches (SACC) played an extremely crucial role during the struggle against apartheid. The role of the SACC was first and foremost to provide a voice for the voiceless. It managed, among other tasks, to actively fill the void left by movements banned by the illegitimate apartheid government. As a result of its fight against the inequalities that existed in South Africa, its work adopted a political character. In the aftermath of post-apartheid South Africa, the SACC was left with the task of redefining its role within South African society and civil society, specifically. The euphoric sentiment in the mid-1990s was in part reflected in the SACC. However, the conclusion reached by the Council in 1995 was that it would also play a role of 'critical solidarity' which essentially meant that it would not shy away from attacking the government when the need arose. Since 1994, the South African government has implemented a number of policies that do not appear to be in the immediate interest of the majority of South African citizens atld have brought church and state into conflict. This thesis attempts to tackle three issues which are pertinent to the South African situation and which shed light on state-civil society interactions. These issues are HIV I Aids, the question of odious debt and the Zimbabwe crisis. By using both primary and secondary sources, the SACC's responses to government's handling of these matters will be compared with the responses of the South African Catholic Bishops Conference in order to determine their relationships with government. The conclusion of this investigation is that the SACC has in fact managed to maintain a position of critical solidarity. It has been faced with numerous challenges with regard to maintaining the fragile boundary of alliance with government on the one hand, and becoming anti-government on the other. However, by forming alliances with other civil society actors as well as fostering a relationship with government in order to facilitate mediation this dissertation argues that the SACC has become an essential member of South Africa's vibrant civil society.
- Full Text:
- Date Issued: 2005
An investigation of local community contributions to the Malawi College of Fisheries curriculum: a case study focussing on the Chambo fishery
- Kachilonda, Dick Daffu Kachanga
- Authors: Kachilonda, Dick Daffu Kachanga
- Date: 2005
- Subjects: Malawi College of Fisheries -- Curricula Fishery management -- Study and teaching Fishery management -- Malawi Fisheries -- Malawi Fishes -- Nyasa, Lake
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1857 , http://hdl.handle.net/10962/d1004537
- Description: The aim of the study was to investigate local community contributions to the existing Malawi College of Fisheries curriculum with a focus on Chambo fishery. Chambo fish (Oreochromis species) is the most favoured fish in Lake Malawi. Chambo catches have declined over the years. Responding to the declining catches, the Fisheries Department is engaged in a number of management options to address the issues. Most of these management options are governed by scientific recommendations and do not consider the socio-economic situation of the people who are dependent on fishery. This approach to fishery has influenced the Malawi College of Fisheries curriculum. The existing curriculum is product-centred, developed by a consultant. During the development of the curriculum, there was little consultation with the lecturers and no consultation with the local communities who are using the resource. The fishing communities have been fishing for a long time and have acquired knowledge, skills and experience worth investigating for its potential role in improving the existing curriculum. Through the use of interviews, focus group discussions and workshops with local communities local knowledge was identified for inclusion into the curriculum. A review of the existing curriculum revealed that it has primarily technical focus, grounded in the protection, control and management of the fish stocks, while the local knowledge has a practical focus based on existing practices and requiring an understanding of the sources of the issues. There is also more emphasis on a historical perspective and the context in which fishing practices take place at the moment. It was evident from the study that local communities have much of knowledge, skills and experience gained over the years of fishing , and if properly utilised, it can improve the MCF curriculum. I therefore recommend in this study that the curriculum be reviewed in order to integrate and draw on the local knowledge through a deliberative and participatory process between the local communities and the government so that it addresses the needs of the local communities and improves the training of the extension workers.
- Full Text:
- Date Issued: 2005
- Authors: Kachilonda, Dick Daffu Kachanga
- Date: 2005
- Subjects: Malawi College of Fisheries -- Curricula Fishery management -- Study and teaching Fishery management -- Malawi Fisheries -- Malawi Fishes -- Nyasa, Lake
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1857 , http://hdl.handle.net/10962/d1004537
- Description: The aim of the study was to investigate local community contributions to the existing Malawi College of Fisheries curriculum with a focus on Chambo fishery. Chambo fish (Oreochromis species) is the most favoured fish in Lake Malawi. Chambo catches have declined over the years. Responding to the declining catches, the Fisheries Department is engaged in a number of management options to address the issues. Most of these management options are governed by scientific recommendations and do not consider the socio-economic situation of the people who are dependent on fishery. This approach to fishery has influenced the Malawi College of Fisheries curriculum. The existing curriculum is product-centred, developed by a consultant. During the development of the curriculum, there was little consultation with the lecturers and no consultation with the local communities who are using the resource. The fishing communities have been fishing for a long time and have acquired knowledge, skills and experience worth investigating for its potential role in improving the existing curriculum. Through the use of interviews, focus group discussions and workshops with local communities local knowledge was identified for inclusion into the curriculum. A review of the existing curriculum revealed that it has primarily technical focus, grounded in the protection, control and management of the fish stocks, while the local knowledge has a practical focus based on existing practices and requiring an understanding of the sources of the issues. There is also more emphasis on a historical perspective and the context in which fishing practices take place at the moment. It was evident from the study that local communities have much of knowledge, skills and experience gained over the years of fishing , and if properly utilised, it can improve the MCF curriculum. I therefore recommend in this study that the curriculum be reviewed in order to integrate and draw on the local knowledge through a deliberative and participatory process between the local communities and the government so that it addresses the needs of the local communities and improves the training of the extension workers.
- Full Text:
- Date Issued: 2005
An analysis of the views of journalists and government officials regarding the impact of new vision's coverage of the Nakivubo Channel Rehabilitation Project
- Authors: Kaheru, Hamis
- Date: 2005
- Subjects: Nakivubo Urban Wetland (Uganda) , Nakivubo Channel Rehabilitation Project , New Vision (Uganda) , Environmental protection -- Press coverage -- Uganda , Government and the press -- Uganda
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3439 , http://hdl.handle.net/10962/d1002893 , Nakivubo Urban Wetland (Uganda) , Nakivubo Channel Rehabilitation Project , New Vision (Uganda) , Environmental protection -- Press coverage -- Uganda , Government and the press -- Uganda
- Full Text:
- Date Issued: 2005
- Authors: Kaheru, Hamis
- Date: 2005
- Subjects: Nakivubo Urban Wetland (Uganda) , Nakivubo Channel Rehabilitation Project , New Vision (Uganda) , Environmental protection -- Press coverage -- Uganda , Government and the press -- Uganda
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3439 , http://hdl.handle.net/10962/d1002893 , Nakivubo Urban Wetland (Uganda) , Nakivubo Channel Rehabilitation Project , New Vision (Uganda) , Environmental protection -- Press coverage -- Uganda , Government and the press -- Uganda
- Full Text:
- Date Issued: 2005
An investigation of how Kampala teenagers who read Straight talk negotiate HIV/AIDS messages
- Kaija, Barbara Night Mbabazi
- Authors: Kaija, Barbara Night Mbabazi
- Date: 2005
- Subjects: AIDS (Disease) -- Uganda -- Kampala Straight talk AIDS (Disease) -- Social aspects -- Uganda -- Kampala AIDS (Disease) in adolescence -- Uganda -- Kampala Teenagers -- Diseases -- Uganda -- Kampala AIDS (Disease) -- Study and teaching AIDS (Disease) in mass media Teenagers -- Sexual behavior -- Uganda -- Kampala AIDS (Disease) -- Prevention -- Uganda -- Kampala
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3440 , http://hdl.handle.net/10962/d1002894
- Description: This study is a qualitative ethnographic investigation of how teenagers in Kampala, Uganda, who read the HIV/AIDS publication aimed at adolescents, Straight Talk, negotiate HIV/AIDS messages. It seeks to establish to what extent these secondary school teenagers accept the key messages (known as ABC; Abstain, Be faithful or use a Condom) and understand the factual aspects of the messages about HIV/AIDS, its process of transmission and prevention. It also seeks to probe how the lived realities of the teenagers affect their particular negotiations of the HIV/AIDS messages. It includes a focus on how proximity to HIV/AIDS, gender and family economic disposition might affect teenagers, negotiation of the HIV/AIDS meanings. To investigate the respondents’ reception of HIV/AIDS messages, the study employed focus groups that consisted of two stages, namely the ‘news game’ and group discussions. In the ‘news game’ stage (Philo, 1990; Kitzinger, 1993) the teenage participants were required to produce a version of a one-page copy of an HIV/AIDS newspaper targeting teenagers. In the second stage of the focus group a structured discussion probed the teenagers’ negotiation of the HIV/AIDS media messages. In the news game, the teenagers on the whole reproduced the key Straight Talk HIV/AIDS messages ‘Abstain, Be faithful or use a Condom’ and also images showing the effects of HIV/AIDS but featured fewer images depicting the factual aspects of HIV/AIDS process of transmission and risky behaviour. In the structured discussion that followed the news game, it was evident that not all the teenagers necessarily believed the messages they produced. In spite of producing the ABC Straight Talk messages, some of them were uncertain and confused about the absolute safety of the condom because of fears that they were either porous, expired or would interfere with sexual pleasure. Secondly, though many of the teenagers in the study reproduced images that showed that they consider marriage as desirable and talked about their desire to abstain from sex till marriage, a considerable number think abstinence is not achievable due to competing values. Thirdly, the participant teenagers could differentiate between HIV and AIDS but many did not realise that with the advent of anti-retroviral drugs even people who have AIDS can look normal. In spite of repeating the Straight Talk message that “no one was safe” and being aware of the risky behaviour that their fellow teenagers get involved in, the teenagers seemed to think that their age cohort is safe from HIV and it is the adults who are likely to infect them. The study findings further indicate that the teenagers’ lived experience at times influence their negotiation of HIV/AIDS media messages. This was probed in terms of economic standing, gender and proximity to HIV/AIDS. In relation to gender one surprising discovery was that certain girls in the study feared getting pregnant more than getting HIV/AIDS. The study finally suggests that these findings are of significance for designing future media initiatives in relation to HIV/AIDS.
- Full Text:
- Date Issued: 2005
- Authors: Kaija, Barbara Night Mbabazi
- Date: 2005
- Subjects: AIDS (Disease) -- Uganda -- Kampala Straight talk AIDS (Disease) -- Social aspects -- Uganda -- Kampala AIDS (Disease) in adolescence -- Uganda -- Kampala Teenagers -- Diseases -- Uganda -- Kampala AIDS (Disease) -- Study and teaching AIDS (Disease) in mass media Teenagers -- Sexual behavior -- Uganda -- Kampala AIDS (Disease) -- Prevention -- Uganda -- Kampala
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3440 , http://hdl.handle.net/10962/d1002894
- Description: This study is a qualitative ethnographic investigation of how teenagers in Kampala, Uganda, who read the HIV/AIDS publication aimed at adolescents, Straight Talk, negotiate HIV/AIDS messages. It seeks to establish to what extent these secondary school teenagers accept the key messages (known as ABC; Abstain, Be faithful or use a Condom) and understand the factual aspects of the messages about HIV/AIDS, its process of transmission and prevention. It also seeks to probe how the lived realities of the teenagers affect their particular negotiations of the HIV/AIDS messages. It includes a focus on how proximity to HIV/AIDS, gender and family economic disposition might affect teenagers, negotiation of the HIV/AIDS meanings. To investigate the respondents’ reception of HIV/AIDS messages, the study employed focus groups that consisted of two stages, namely the ‘news game’ and group discussions. In the ‘news game’ stage (Philo, 1990; Kitzinger, 1993) the teenage participants were required to produce a version of a one-page copy of an HIV/AIDS newspaper targeting teenagers. In the second stage of the focus group a structured discussion probed the teenagers’ negotiation of the HIV/AIDS media messages. In the news game, the teenagers on the whole reproduced the key Straight Talk HIV/AIDS messages ‘Abstain, Be faithful or use a Condom’ and also images showing the effects of HIV/AIDS but featured fewer images depicting the factual aspects of HIV/AIDS process of transmission and risky behaviour. In the structured discussion that followed the news game, it was evident that not all the teenagers necessarily believed the messages they produced. In spite of producing the ABC Straight Talk messages, some of them were uncertain and confused about the absolute safety of the condom because of fears that they were either porous, expired or would interfere with sexual pleasure. Secondly, though many of the teenagers in the study reproduced images that showed that they consider marriage as desirable and talked about their desire to abstain from sex till marriage, a considerable number think abstinence is not achievable due to competing values. Thirdly, the participant teenagers could differentiate between HIV and AIDS but many did not realise that with the advent of anti-retroviral drugs even people who have AIDS can look normal. In spite of repeating the Straight Talk message that “no one was safe” and being aware of the risky behaviour that their fellow teenagers get involved in, the teenagers seemed to think that their age cohort is safe from HIV and it is the adults who are likely to infect them. The study findings further indicate that the teenagers’ lived experience at times influence their negotiation of HIV/AIDS media messages. This was probed in terms of economic standing, gender and proximity to HIV/AIDS. In relation to gender one surprising discovery was that certain girls in the study feared getting pregnant more than getting HIV/AIDS. The study finally suggests that these findings are of significance for designing future media initiatives in relation to HIV/AIDS.
- Full Text:
- Date Issued: 2005
Trauma, imagery and the therapeutic relationship : Langu's story
- Karpelowsky, B, Edwards, D J A
- Authors: Karpelowsky, B , Edwards, D J A
- Date: 2005
- Language: English
- Type: Article
- Identifier: vital:6268 , http://hdl.handle.net/10962/d1008267
- Description: This paper, a phenomenological case study, describes the psychotherapy of Langu (pseudonym), a 21-year-old student, who presented with Acute Stress Disorder following a series of motor accidents that affected him and his family. Langu's most distressing experience was having to identify his brother's mutilated and severely burned body. Because of the intensity of the intrusive re-experiencing of traumatic imagery and the degree of dissociative numbing, Langu participated in four intensive guided imagery sessions, which involved reliving the incident, and imaginal dialogues with his dead brother. Session records and supervision notes from the therapy process that unfolded over 22 sessions served as the basis for a thematically selective case narrative. Additional material was obtained from several research interviews with Langu over the following months. The narrative highlights the impact of the imagery work as well as relational aspects of the therapy. The case narrative provides a source for examining many aspects of the psychological impact of trauma and the path to healing, as well as the dilemmas and challenges faced by therapists working with traumatised individuals.
- Full Text:
- Date Issued: 2005
- Authors: Karpelowsky, B , Edwards, D J A
- Date: 2005
- Language: English
- Type: Article
- Identifier: vital:6268 , http://hdl.handle.net/10962/d1008267
- Description: This paper, a phenomenological case study, describes the psychotherapy of Langu (pseudonym), a 21-year-old student, who presented with Acute Stress Disorder following a series of motor accidents that affected him and his family. Langu's most distressing experience was having to identify his brother's mutilated and severely burned body. Because of the intensity of the intrusive re-experiencing of traumatic imagery and the degree of dissociative numbing, Langu participated in four intensive guided imagery sessions, which involved reliving the incident, and imaginal dialogues with his dead brother. Session records and supervision notes from the therapy process that unfolded over 22 sessions served as the basis for a thematically selective case narrative. Additional material was obtained from several research interviews with Langu over the following months. The narrative highlights the impact of the imagery work as well as relational aspects of the therapy. The case narrative provides a source for examining many aspects of the psychological impact of trauma and the path to healing, as well as the dilemmas and challenges faced by therapists working with traumatised individuals.
- Full Text:
- Date Issued: 2005
The Dassie and the Hunter: A South African Meeting
- Authors: Kaschula, Russell H
- Date: 2005
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/175147 , vital:42547 , https://doi.org/10.4314/tvl.v43i1.29727
- Description: This book does not resemble any of Jeff Opland’s previous academic works. There is no similarity in style, and to some extent content. His previous books, namely, Xhosa oral poetry: Aspects of a black South African tradition (Cambridge University Press, 1983), and Xhosa poets and poetry (David Philip, 1998), were written as purely scientific, academic works. The Dassie and the Hunter amounts to a subtle snub of academia and its restrictive rules. Though written by Opland, it is as if he and his research subject, Manisi, have colluded to make this work different and special, in a personal mystical way, disregarding academic etiquette, weaving a more creative, poetic tapestry. This makes the book an interesting read. In style and content, it is neither rigorously academic, solely biographical, nor purely creative. It evades classification. It is individualistic.
- Full Text:
- Date Issued: 2005
- Authors: Kaschula, Russell H
- Date: 2005
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/175147 , vital:42547 , https://doi.org/10.4314/tvl.v43i1.29727
- Description: This book does not resemble any of Jeff Opland’s previous academic works. There is no similarity in style, and to some extent content. His previous books, namely, Xhosa oral poetry: Aspects of a black South African tradition (Cambridge University Press, 1983), and Xhosa poets and poetry (David Philip, 1998), were written as purely scientific, academic works. The Dassie and the Hunter amounts to a subtle snub of academia and its restrictive rules. Though written by Opland, it is as if he and his research subject, Manisi, have colluded to make this work different and special, in a personal mystical way, disregarding academic etiquette, weaving a more creative, poetic tapestry. This makes the book an interesting read. In style and content, it is neither rigorously academic, solely biographical, nor purely creative. It evades classification. It is individualistic.
- Full Text:
- Date Issued: 2005
Biological removal of nitrogen species from metal-processing wastewater
- Kasia, J M, Duncan, J R, Burgess, Jo E
- Authors: Kasia, J M , Duncan, J R , Burgess, Jo E
- Date: 2005
- Language: English
- Type: Article
- Identifier: vital:6482 , http://hdl.handle.net/10962/d1006256
- Description: Although several nitrification/denitrification processes are established for the removal of ammonia and nitrate from municipal and industrial wastewaters, there are few reported results on the removal of these ions from metal-processing and finishing wastewaters. Unlike municipal wastewater, there is very little organic content in metal-processing wastewaters. Sources of ammonia and nitrate in the wastewater include the use of ammonium-nitrate-fuel oil as a blasting agent, and the use of other nitrogen-containing reagents during processing. The objective of this work was to investigate a biological process for the removal of nitrogenous compounds from real metal-processing wastewater. The system comprised an aerobic continuously stirred tank reactor (CSTR) followed by an anaerobic packed column and was run using real wastewater from a metal-processing operation. The system was inoculated using humus sludge from a municipal trickling filter and a period of approximately four weeks was required for a denitrifying biofilm to develop. Results showed that ammonia removal occurred readily in the CSTR while nitrite oxidation was slower to develop. The CSTR was found to be suitable for ammonia oxidation; up to 89% ammonia removal was achieved. By employing an integrated process comprising nitrification and denitrification, high ammonia removal efficiencies can be obtained. An effluent that is low in ammonia can be obtained with this system with additional carbon introduced after the CSTR. The gravel-packed column reactor was found to be unsuitable for the removal of nitrate in the configuration used (maximum 15% removal efficiency). The critical parameters for denitrification are nitrate concentration, temperature, influent flow rate and mean cell retention time. Nitrate removal did not meet the expectations projected by previous authors' work using synthetic wastewater.
- Full Text:
- Date Issued: 2005
- Authors: Kasia, J M , Duncan, J R , Burgess, Jo E
- Date: 2005
- Language: English
- Type: Article
- Identifier: vital:6482 , http://hdl.handle.net/10962/d1006256
- Description: Although several nitrification/denitrification processes are established for the removal of ammonia and nitrate from municipal and industrial wastewaters, there are few reported results on the removal of these ions from metal-processing and finishing wastewaters. Unlike municipal wastewater, there is very little organic content in metal-processing wastewaters. Sources of ammonia and nitrate in the wastewater include the use of ammonium-nitrate-fuel oil as a blasting agent, and the use of other nitrogen-containing reagents during processing. The objective of this work was to investigate a biological process for the removal of nitrogenous compounds from real metal-processing wastewater. The system comprised an aerobic continuously stirred tank reactor (CSTR) followed by an anaerobic packed column and was run using real wastewater from a metal-processing operation. The system was inoculated using humus sludge from a municipal trickling filter and a period of approximately four weeks was required for a denitrifying biofilm to develop. Results showed that ammonia removal occurred readily in the CSTR while nitrite oxidation was slower to develop. The CSTR was found to be suitable for ammonia oxidation; up to 89% ammonia removal was achieved. By employing an integrated process comprising nitrification and denitrification, high ammonia removal efficiencies can be obtained. An effluent that is low in ammonia can be obtained with this system with additional carbon introduced after the CSTR. The gravel-packed column reactor was found to be unsuitable for the removal of nitrate in the configuration used (maximum 15% removal efficiency). The critical parameters for denitrification are nitrate concentration, temperature, influent flow rate and mean cell retention time. Nitrate removal did not meet the expectations projected by previous authors' work using synthetic wastewater.
- Full Text:
- Date Issued: 2005
The role of communication in the management and leadership of a secondary school in Namibia
- Authors: Kaura, Unjee M
- Date: 2005
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1862 , http://hdl.handle.net/10962/d1004559
- Description: Communication is a complex phenomenon, widely regarded as the lifeblood of every organisation, and ironically one of the least researched areas, at least in the field of leadership and management in an educational context. The paucity of literature in this field is evidence of this. This study is an attempt to explore and gain understanding of teachers' experiences and perceptions of the role and functions of communication within an educational organisation, in this case a secondary school in Namibia. The study is an interpretive case study, and employed questionnaires and interviews to gather data from selected participants at the site of research. The findings of the study highlight the dual role of communication as a functioning mechanism as well as a social or binding factor. The role of communication emerges as an essential element in the democratic functioning of the school. It is through communication that democratic practice is achieved as a vehicle for involvement in decision-making, sharing, teamwork, and as a medium for leadership leading to empowerment, human development and organisational development, bringing about change through the sharing of vision. Both formal and informal communication are shown to be functional to the institution. Some of the challenges that have emerged are the dangers of careless and malicious 'badmouthing' in informal communication, the persistence of some degree of top-down communication, and the challenges of communication in multi-cultural settings. The study highlights the need for strategies to improve communication, such as workshops on interpersonal communication.
- Full Text:
- Date Issued: 2005
- Authors: Kaura, Unjee M
- Date: 2005
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1862 , http://hdl.handle.net/10962/d1004559
- Description: Communication is a complex phenomenon, widely regarded as the lifeblood of every organisation, and ironically one of the least researched areas, at least in the field of leadership and management in an educational context. The paucity of literature in this field is evidence of this. This study is an attempt to explore and gain understanding of teachers' experiences and perceptions of the role and functions of communication within an educational organisation, in this case a secondary school in Namibia. The study is an interpretive case study, and employed questionnaires and interviews to gather data from selected participants at the site of research. The findings of the study highlight the dual role of communication as a functioning mechanism as well as a social or binding factor. The role of communication emerges as an essential element in the democratic functioning of the school. It is through communication that democratic practice is achieved as a vehicle for involvement in decision-making, sharing, teamwork, and as a medium for leadership leading to empowerment, human development and organisational development, bringing about change through the sharing of vision. Both formal and informal communication are shown to be functional to the institution. Some of the challenges that have emerged are the dangers of careless and malicious 'badmouthing' in informal communication, the persistence of some degree of top-down communication, and the challenges of communication in multi-cultural settings. The study highlights the need for strategies to improve communication, such as workshops on interpersonal communication.
- Full Text:
- Date Issued: 2005
Inspectors of education's perceptions of female principalship in the Rundu region of Namibia
- Authors: Kawana, Irene
- Date: 2005
- Subjects: Women school principals -- Namibia -- Rundu , Educational leadership -- Namibia -- Rundu , Sex discrimination in employment -- Namibia , School supervisors -- Namibia -- Attitudes
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:2006 , http://hdl.handle.net/10962/d1015746
- Description: While women constitute more than 51% of the population and far outnumber men in teaching positions in Namibia, very few occupy positions of leadership. Male candidates are still favoured for top positions, thereby denying women the chance to gain entrance to these positions. One of the reasons for this imbalance seems to be that, in spite of conscious political effort and legislation, women may still be perceived as less effective leaders than men. This research focused on leadership in education, in particular school principals, and explored the perceptions of female principalship held by school inspectors. Three school inspectors from the Rundu Education Region were purposefully selected and interviewed. Inspectors were selected on the grounds of their considerable influence in the selection and appointment of school principals. The study found that these inspectors favour school principals who show commitment to their work, have good interpersonal working relationships, are caring, good listeners, visionary and produce good results. The inspectors attribute female principals’ success to their traditionally perceived characteristics, such as caring leadership and ability to develop good human relations. Instead of perceiving these qualities as professionally negative (as is sometimes argued in the literature) the inspectors see them as indisputable assets to leadership. The respondents acknowledge the cultural stereotyping that may have influenced male attitudes to women in the past, but argue that good leadership is not specific to gender, but part of the qualities a person possesses, regardless of sex. This study concludes that, contrary to what has been reported in many studies, these inspectors perceive women principals as effective – equal to their male counterparts or sometimes even more effective - because they are caring, well organized and good at communicating and establishing relations with others. Though these qualities are different from the traditional masculine qualities which include independence and emotional strength, the respondents recognize and legitimize them as preferred qualities in current effective leadership practice.
- Full Text:
- Date Issued: 2005
- Authors: Kawana, Irene
- Date: 2005
- Subjects: Women school principals -- Namibia -- Rundu , Educational leadership -- Namibia -- Rundu , Sex discrimination in employment -- Namibia , School supervisors -- Namibia -- Attitudes
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:2006 , http://hdl.handle.net/10962/d1015746
- Description: While women constitute more than 51% of the population and far outnumber men in teaching positions in Namibia, very few occupy positions of leadership. Male candidates are still favoured for top positions, thereby denying women the chance to gain entrance to these positions. One of the reasons for this imbalance seems to be that, in spite of conscious political effort and legislation, women may still be perceived as less effective leaders than men. This research focused on leadership in education, in particular school principals, and explored the perceptions of female principalship held by school inspectors. Three school inspectors from the Rundu Education Region were purposefully selected and interviewed. Inspectors were selected on the grounds of their considerable influence in the selection and appointment of school principals. The study found that these inspectors favour school principals who show commitment to their work, have good interpersonal working relationships, are caring, good listeners, visionary and produce good results. The inspectors attribute female principals’ success to their traditionally perceived characteristics, such as caring leadership and ability to develop good human relations. Instead of perceiving these qualities as professionally negative (as is sometimes argued in the literature) the inspectors see them as indisputable assets to leadership. The respondents acknowledge the cultural stereotyping that may have influenced male attitudes to women in the past, but argue that good leadership is not specific to gender, but part of the qualities a person possesses, regardless of sex. This study concludes that, contrary to what has been reported in many studies, these inspectors perceive women principals as effective – equal to their male counterparts or sometimes even more effective - because they are caring, well organized and good at communicating and establishing relations with others. Though these qualities are different from the traditional masculine qualities which include independence and emotional strength, the respondents recognize and legitimize them as preferred qualities in current effective leadership practice.
- Full Text:
- Date Issued: 2005
Selecting medicinal plants for cultivation at Nqabara on the Eastern Cape Wild Coast, South Africa
- Keirungi, J, Fabricius, Christo
- Authors: Keirungi, J , Fabricius, Christo
- Date: 2005
- Language: English
- Type: Article
- Identifier: vital:6637 , http://hdl.handle.net/10962/d1006862
- Description: [From introduction:] The intensive harvesting of medicinal plants for commercial trade in South Africa poses a threat to many species. Cultivation has therefore been considered as an alternative to collection in the wild. This paper aims to assess the feasibility of cultivating medicinal plants in the Nqabara Administrative Area on South Africa's Wild Coast. A combination of participatory and formal research methods was used to collect data on the importance of medicinal plants, collection localities, market prices, the time spent collecting plants and their ease of cultivation. The values attached to medicinal plants were mainly dependent on their market prices. Four of the five Nqabara traditional healers interviewed cultivated these plants in their home gardens, but many medicinal products were obtained in indigenous forests from the bark of large trees, which were unsuitable for cultivation. Collectors said that the proximity of forests to their homesteads and the richness of forests in medicinal plants influenced their selection of harvesting localities. There was no correlation between time spent collecting species and their market prices. These prices were, however, positively correlated with the species' perceived healing properties. Users acknowledged that harvesting had an adverse effect on large trees, are eager to cultivate them and are taking action to conserve indigenous forests. Community-based enterprises should focus on species that are easy to cultivate and have a high demand, such as Stangeria eriopus, Acalypha glabrata and Behnia reticulata but not Araujia sericifera, which is exotic and abundant. The main barriers to commercial cultivation are availability of suitable land, water, lack of start-up capital, and access to markets and to seeds. Cultivation of medicinal plants could contribute to the economic empowerment of women in rural areas.
- Full Text:
- Date Issued: 2005
- Authors: Keirungi, J , Fabricius, Christo
- Date: 2005
- Language: English
- Type: Article
- Identifier: vital:6637 , http://hdl.handle.net/10962/d1006862
- Description: [From introduction:] The intensive harvesting of medicinal plants for commercial trade in South Africa poses a threat to many species. Cultivation has therefore been considered as an alternative to collection in the wild. This paper aims to assess the feasibility of cultivating medicinal plants in the Nqabara Administrative Area on South Africa's Wild Coast. A combination of participatory and formal research methods was used to collect data on the importance of medicinal plants, collection localities, market prices, the time spent collecting plants and their ease of cultivation. The values attached to medicinal plants were mainly dependent on their market prices. Four of the five Nqabara traditional healers interviewed cultivated these plants in their home gardens, but many medicinal products were obtained in indigenous forests from the bark of large trees, which were unsuitable for cultivation. Collectors said that the proximity of forests to their homesteads and the richness of forests in medicinal plants influenced their selection of harvesting localities. There was no correlation between time spent collecting species and their market prices. These prices were, however, positively correlated with the species' perceived healing properties. Users acknowledged that harvesting had an adverse effect on large trees, are eager to cultivate them and are taking action to conserve indigenous forests. Community-based enterprises should focus on species that are easy to cultivate and have a high demand, such as Stangeria eriopus, Acalypha glabrata and Behnia reticulata but not Araujia sericifera, which is exotic and abundant. The main barriers to commercial cultivation are availability of suitable land, water, lack of start-up capital, and access to markets and to seeds. Cultivation of medicinal plants could contribute to the economic empowerment of women in rural areas.
- Full Text:
- Date Issued: 2005
Puerulus and early juvenile recruitment of the rock lobster jasus lalandii in relation to the environment at Lüderitz Bay, Namibia
- Authors: Keulder, Felicia Juanita
- Date: 2005
- Subjects: Jasus lalandii , Lobster fisheries -- Namibia , Lobster culture -- Namibia
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5315 , http://hdl.handle.net/10962/d1005160 , Jasus lalandii , Lobster fisheries -- Namibia , Lobster culture -- Namibia
- Description: A global decline in the lobster fishery has necessitated the growout of wild-caught postlarvae (pueruli) on farms to meet the worlds lobster demand. A limited knowledge on puerulus settlement in the West Coast rock lobster (Jasus lalandii) constitutes a major barrier for J. lalandii culture development in Southern Africa. As an extension of an existing long-term puerulus monitoring program of the Ministry of Fisheries and Marine Resources of Namibia, the present study monitored puerulus recruitment (supply), puerulus condition and juvenile growth of J. lalandii and their relationship with environmental variables on an oyster farm at Lüderitz Bay, Namibia. Implications for lobster aquaculture and fisheries management are discussed. Oyster bags, crates and collectors were sampled daily, weekly and bimonthly, for pueruli and juveniles, respectively, between August 2001 and July 2003 to establish spatialtemporal patterns in their distribution. Animals were transported to the laboratory for morphometric analyses where they were staged as puerulus (Pt = transparent; Pp = pigmented) and juvenile lobsters. The carapace lengths (0.1mm CL) and wet weights (0.01gram) of animals were recorded. Carapace length frequencies were subjected to Modal Progression analysis to identify early juvenile cohorts and calculate their growths. The weight-length ratios calculated and percentage fat content were used as indices of nutritional condition. Seasonal peaks in puerulus and juvenile abundance were estimated using Periodic Regression analysis. The relationships of puerulus and juvenile abundance with respect to sea surface temperature (SST), wind speed-direction, moon phase, swell and tidal range were established using time lag analysis (ADL). Transparent pueruli were randomly distributed on oyster bags and crates, and also between collector sites, suggesting that they have no particular settlement preference for certain areas on these structures (p>0.05; n=150). Pigmented puerulus (p<0.05; n=566) and juveniles (p<0.05; n=3528) preferred structurally complex structures that provided better shelter such as crates, which were more sheltered from sea swells, compared to oyster bags. Among oyster rafts, pigmented puerulus and juveniles preferred occupying the sheltered and centred raft areas, which provided better protection from wave action, compared to exposed raft areas, which were exposed to the incoming swell. Puerulus and juvenile lobster appeared to recolonise adjacent bags and crates, and possibly migrate to the substrate and off the farm due to the disturbance of the habitat during harvesting. The booth crevice collector was more efficient in collecting puerulus possibly due to the high structurally complex habitat and the better shelter they provided compared to the hogshair collector. The occupation of structurally complex habitats by early benthic stages may be related to morphological changes associated with metamorphosis. Puerulus settlement peaked during early spring (August-September) and was related to low sea surface temperatures (12.3°C), strong south winds, and moderate swells in the week preceding settlement. These conditions are synonymous with the “spring upwelling” season of the Lüderitz upwelling cell in the central Benguela current region. Puerulus nutritional condition peaked during this period possibly due to high levels of planktonic food (due to high nutrients from upwelling) that was available to the late stage phyllosoma larvae further offshore. A “good” puerulus settlement year during 2000 was associated with lower than average SST (11.6°C) and strong south winds and was followed by “poor” puerulus settlement years during 2001 and 2002 when higher than average SST were experienced with below average wind speeds experienced during 2001 only. Puerulus of J. lalandii recruited in high numbers into Lüderitz Bay during the new moon, full moon and last quarter moon phases by making use of the increased tides during these phases of the lunar cycle. Peak juvenile abundance during early summer (November-December) lagged by 8 weeks was significantly correlated with peak puerulus abundance. Puerulus size was similar (8.5–9.7mm CL) over the study period. Juvenile cohorts, 9.9-20.6mm CL in size recruited in 2 distinct waves in August 2001-June 2002 and July 2002-February 2003. The 2001/2002 recruits had higher monthly growth increments and better nutritional condition compared to 2002/2003 recruits. Peak frequencies of 2nd moult juveniles (9.9- 10.8mm CL) occurred in September of both recruitment events with nutritional condition being poorest during the 2002/2003 event. The nutritional condition of the settling puerulus did not appear to be related to the subsequent growth of juvenile lobster. These preliminary results suggest that pueruli recruit once a year mainly during late winter/ early spring under conditions typical of coastal upwelling in the Benguela current near Lüderitz. It appears that puerulus settlement is driven by favourable shoreward currents, which help in transporting puerulus to their settlement grounds. Puerulus supply is highly variable between years, which appears to be consistent with a highly variable Benguela environment. The oyster farm supported a substantial standing stock averaging 123 800 lobster per day (range: 22 600-325 300 lobster per day) of which 26 600 were puerulus and 97 200 were juveniles, that may have been harvested once off on any given day during the sample period. Monthly harvesting of the total lobster standing stock during the one and a half year sampling period was just over 2 million lobsters (505 700 pueruli and 1.85 million juveniles) and would potentially have been sufficient seed for a 200 ton lobster production in puerulus lobster growout facilities. In the light of high inter-annual variation in puerulus settlement observed at Lüderitz, the seed supply at the Lüderitz oyster farm is clearly limited and therefore it is prudent that other sites of high puerulus settlement is established before large commercial scale lobster growout can commence. The migration of lobster off the farm suggested that these lobsters potentially recruit to the fishery and therefore harvesting the entire standing stock on the farm may have adverse negative effects on the wild fishery. A policy decision will be required as to whether more efficient harvesting of lobster from the farm should be allowed. If puerulus removal in J. lalandii for aquaculture is allowed in the near future, it should be conducted on an experimental scale or small commercial scale until the potential effects on recruitment into the fishery are clearer.
- Full Text:
- Date Issued: 2005
- Authors: Keulder, Felicia Juanita
- Date: 2005
- Subjects: Jasus lalandii , Lobster fisheries -- Namibia , Lobster culture -- Namibia
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5315 , http://hdl.handle.net/10962/d1005160 , Jasus lalandii , Lobster fisheries -- Namibia , Lobster culture -- Namibia
- Description: A global decline in the lobster fishery has necessitated the growout of wild-caught postlarvae (pueruli) on farms to meet the worlds lobster demand. A limited knowledge on puerulus settlement in the West Coast rock lobster (Jasus lalandii) constitutes a major barrier for J. lalandii culture development in Southern Africa. As an extension of an existing long-term puerulus monitoring program of the Ministry of Fisheries and Marine Resources of Namibia, the present study monitored puerulus recruitment (supply), puerulus condition and juvenile growth of J. lalandii and their relationship with environmental variables on an oyster farm at Lüderitz Bay, Namibia. Implications for lobster aquaculture and fisheries management are discussed. Oyster bags, crates and collectors were sampled daily, weekly and bimonthly, for pueruli and juveniles, respectively, between August 2001 and July 2003 to establish spatialtemporal patterns in their distribution. Animals were transported to the laboratory for morphometric analyses where they were staged as puerulus (Pt = transparent; Pp = pigmented) and juvenile lobsters. The carapace lengths (0.1mm CL) and wet weights (0.01gram) of animals were recorded. Carapace length frequencies were subjected to Modal Progression analysis to identify early juvenile cohorts and calculate their growths. The weight-length ratios calculated and percentage fat content were used as indices of nutritional condition. Seasonal peaks in puerulus and juvenile abundance were estimated using Periodic Regression analysis. The relationships of puerulus and juvenile abundance with respect to sea surface temperature (SST), wind speed-direction, moon phase, swell and tidal range were established using time lag analysis (ADL). Transparent pueruli were randomly distributed on oyster bags and crates, and also between collector sites, suggesting that they have no particular settlement preference for certain areas on these structures (p>0.05; n=150). Pigmented puerulus (p<0.05; n=566) and juveniles (p<0.05; n=3528) preferred structurally complex structures that provided better shelter such as crates, which were more sheltered from sea swells, compared to oyster bags. Among oyster rafts, pigmented puerulus and juveniles preferred occupying the sheltered and centred raft areas, which provided better protection from wave action, compared to exposed raft areas, which were exposed to the incoming swell. Puerulus and juvenile lobster appeared to recolonise adjacent bags and crates, and possibly migrate to the substrate and off the farm due to the disturbance of the habitat during harvesting. The booth crevice collector was more efficient in collecting puerulus possibly due to the high structurally complex habitat and the better shelter they provided compared to the hogshair collector. The occupation of structurally complex habitats by early benthic stages may be related to morphological changes associated with metamorphosis. Puerulus settlement peaked during early spring (August-September) and was related to low sea surface temperatures (12.3°C), strong south winds, and moderate swells in the week preceding settlement. These conditions are synonymous with the “spring upwelling” season of the Lüderitz upwelling cell in the central Benguela current region. Puerulus nutritional condition peaked during this period possibly due to high levels of planktonic food (due to high nutrients from upwelling) that was available to the late stage phyllosoma larvae further offshore. A “good” puerulus settlement year during 2000 was associated with lower than average SST (11.6°C) and strong south winds and was followed by “poor” puerulus settlement years during 2001 and 2002 when higher than average SST were experienced with below average wind speeds experienced during 2001 only. Puerulus of J. lalandii recruited in high numbers into Lüderitz Bay during the new moon, full moon and last quarter moon phases by making use of the increased tides during these phases of the lunar cycle. Peak juvenile abundance during early summer (November-December) lagged by 8 weeks was significantly correlated with peak puerulus abundance. Puerulus size was similar (8.5–9.7mm CL) over the study period. Juvenile cohorts, 9.9-20.6mm CL in size recruited in 2 distinct waves in August 2001-June 2002 and July 2002-February 2003. The 2001/2002 recruits had higher monthly growth increments and better nutritional condition compared to 2002/2003 recruits. Peak frequencies of 2nd moult juveniles (9.9- 10.8mm CL) occurred in September of both recruitment events with nutritional condition being poorest during the 2002/2003 event. The nutritional condition of the settling puerulus did not appear to be related to the subsequent growth of juvenile lobster. These preliminary results suggest that pueruli recruit once a year mainly during late winter/ early spring under conditions typical of coastal upwelling in the Benguela current near Lüderitz. It appears that puerulus settlement is driven by favourable shoreward currents, which help in transporting puerulus to their settlement grounds. Puerulus supply is highly variable between years, which appears to be consistent with a highly variable Benguela environment. The oyster farm supported a substantial standing stock averaging 123 800 lobster per day (range: 22 600-325 300 lobster per day) of which 26 600 were puerulus and 97 200 were juveniles, that may have been harvested once off on any given day during the sample period. Monthly harvesting of the total lobster standing stock during the one and a half year sampling period was just over 2 million lobsters (505 700 pueruli and 1.85 million juveniles) and would potentially have been sufficient seed for a 200 ton lobster production in puerulus lobster growout facilities. In the light of high inter-annual variation in puerulus settlement observed at Lüderitz, the seed supply at the Lüderitz oyster farm is clearly limited and therefore it is prudent that other sites of high puerulus settlement is established before large commercial scale lobster growout can commence. The migration of lobster off the farm suggested that these lobsters potentially recruit to the fishery and therefore harvesting the entire standing stock on the farm may have adverse negative effects on the wild fishery. A policy decision will be required as to whether more efficient harvesting of lobster from the farm should be allowed. If puerulus removal in J. lalandii for aquaculture is allowed in the near future, it should be conducted on an experimental scale or small commercial scale until the potential effects on recruitment into the fishery are clearer.
- Full Text:
- Date Issued: 2005
Betwixt and between: exploring the passage of liminal space
- Authors: Key, Michelle
- Date: 2005
- Subjects: Bourgeois, Louis, 1911- Spider , Art and anthropology , Art criticism , Liminality
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2406 , http://hdl.handle.net/10962/d1002202 , Bourgeois, Louis, 1911- Spider , Art and anthropology , Art criticism , Liminality
- Description: The focus of this thesis is on the liminal space, limen being Latin for threshold. The liminal space is used as a means of figuring and reading artworks that appear to be in a process of becoming and disappearing. A dialectical and reciprocal reading is made of Bourgeois’ “neo-Baroque” artwork Spider (1997) and Michelle Key’s Betwixt-in-Between (2004). Liminality here is discussed within the theoretical framework of several key conceptual concerns, including abjection (as examined principally by Julia Kristeva), Baroque thought (as discussed by Mieke Bal, Gilles Deleuze, Jacques Lacan and Slavoj Žižek) and allegory (as figured primarily by Walter Benjamin and commentators on Benjamin’s writings). What links these concerns are their focus on indeterminacy, instability, and process as opposed to certitude and finitude. The exploration of the inscription of time in space; that is the temporal process, which gives rise to, which produces, the spatial dimension, is attempted in order to make meaning, however provisionally, of what may be argued to destabilise meaning and to consider possibilities for both art-making and interpretation that would engage critically with this instability.
- Full Text:
- Date Issued: 2005
- Authors: Key, Michelle
- Date: 2005
- Subjects: Bourgeois, Louis, 1911- Spider , Art and anthropology , Art criticism , Liminality
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2406 , http://hdl.handle.net/10962/d1002202 , Bourgeois, Louis, 1911- Spider , Art and anthropology , Art criticism , Liminality
- Description: The focus of this thesis is on the liminal space, limen being Latin for threshold. The liminal space is used as a means of figuring and reading artworks that appear to be in a process of becoming and disappearing. A dialectical and reciprocal reading is made of Bourgeois’ “neo-Baroque” artwork Spider (1997) and Michelle Key’s Betwixt-in-Between (2004). Liminality here is discussed within the theoretical framework of several key conceptual concerns, including abjection (as examined principally by Julia Kristeva), Baroque thought (as discussed by Mieke Bal, Gilles Deleuze, Jacques Lacan and Slavoj Žižek) and allegory (as figured primarily by Walter Benjamin and commentators on Benjamin’s writings). What links these concerns are their focus on indeterminacy, instability, and process as opposed to certitude and finitude. The exploration of the inscription of time in space; that is the temporal process, which gives rise to, which produces, the spatial dimension, is attempted in order to make meaning, however provisionally, of what may be argued to destabilise meaning and to consider possibilities for both art-making and interpretation that would engage critically with this instability.
- Full Text:
- Date Issued: 2005