Screening of the white margined sole, Synaptura marginata (Soleidae), as a candidate for aquaculture in South Africa
- Authors: Thompson, Ernst Frederick
- Date: 2004
- Subjects: Flatfishes -- South Africa , Aquaculture -- South Africa , Soleidae -- South Africa , Soleidae
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5207 , http://hdl.handle.net/10962/d1004523 , Flatfishes -- South Africa , Aquaculture -- South Africa , Soleidae -- South Africa , Soleidae
- Description: The white margined sole Synaptura marginata (Soleidae) was isolated as the most likely candidate for flatfish aquaculture in South Africa. The aim of the study was to screen the sole as a candidate aquaculture species by way of a comprehensive study of its biology and life history strategy and to identify possible "bottlenecks". The study was undertaken on the assumption that the biological data would provide valuable information for developing specific technologies that might be required for the farming of this species. Specimens were collected monthly by spearing along the Eastern Cape coast of South Africa between December 2000 and March 2002. Length-at-age data required for modeling the growth of S. marginata was obtained from sectioned otoliths. A Von Bertalanffy growth model with an absolute error structure best describes the growth for this species. The model parameters were: L∞ = 429.5 mm TL, K = 0.24 and t₀ = -1 .79 years. Analysis of gut contents showed that S. marginata feed exclusively on polychaete worms, mainly of the genus Morphysa. S. marginata shows a protracted summer spawning season of six months, from October to April. This was determined by the calculation of a monthly gonadosomatic index and a macroscopic maturity scale. Histological examination of the ovaries revealed five ovarian developmental stages. Size at 50% and 100% sexual maturity for females was calculated to be 235 mm TL and 300 mm TL (ca. 1.5 - 2.5 years of age) and all males> 154 mm TL were mature. S. marginata is a batch spawner, releasing a minimum of 3 batches of eggs per year. Relative fecundity is high (34000 eggs per year I kg) and this coupled with the protracted spawning season would make it possible to obtain adequate numbers of juveniles (for farming) for approximately five to six months of the year. Comparative analysis of the biological characteristics in relation to other soles farmed elsewhere in the world suggests that S. marginata is a suitable candidate for marine fish culture in South Africa.
- Full Text:
- Date Issued: 2004
- Authors: Thompson, Ernst Frederick
- Date: 2004
- Subjects: Flatfishes -- South Africa , Aquaculture -- South Africa , Soleidae -- South Africa , Soleidae
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5207 , http://hdl.handle.net/10962/d1004523 , Flatfishes -- South Africa , Aquaculture -- South Africa , Soleidae -- South Africa , Soleidae
- Description: The white margined sole Synaptura marginata (Soleidae) was isolated as the most likely candidate for flatfish aquaculture in South Africa. The aim of the study was to screen the sole as a candidate aquaculture species by way of a comprehensive study of its biology and life history strategy and to identify possible "bottlenecks". The study was undertaken on the assumption that the biological data would provide valuable information for developing specific technologies that might be required for the farming of this species. Specimens were collected monthly by spearing along the Eastern Cape coast of South Africa between December 2000 and March 2002. Length-at-age data required for modeling the growth of S. marginata was obtained from sectioned otoliths. A Von Bertalanffy growth model with an absolute error structure best describes the growth for this species. The model parameters were: L∞ = 429.5 mm TL, K = 0.24 and t₀ = -1 .79 years. Analysis of gut contents showed that S. marginata feed exclusively on polychaete worms, mainly of the genus Morphysa. S. marginata shows a protracted summer spawning season of six months, from October to April. This was determined by the calculation of a monthly gonadosomatic index and a macroscopic maturity scale. Histological examination of the ovaries revealed five ovarian developmental stages. Size at 50% and 100% sexual maturity for females was calculated to be 235 mm TL and 300 mm TL (ca. 1.5 - 2.5 years of age) and all males> 154 mm TL were mature. S. marginata is a batch spawner, releasing a minimum of 3 batches of eggs per year. Relative fecundity is high (34000 eggs per year I kg) and this coupled with the protracted spawning season would make it possible to obtain adequate numbers of juveniles (for farming) for approximately five to six months of the year. Comparative analysis of the biological characteristics in relation to other soles farmed elsewhere in the world suggests that S. marginata is a suitable candidate for marine fish culture in South Africa.
- Full Text:
- Date Issued: 2004
Service quality importance-performance analysis as a strategic tool for management : the exploration of key customer satisfaction drivers in a South African electricity utility
- Authors: MacColl, Barry
- Date: 2004
- Subjects: Eskom (Firm) Electric power distribution -- Customer services -- South Africa -- Eastern Cape Electric power distribution -- South Africa -- Eastern Cape -- Quality control Customer services -- Quality control Customer services -- Rating of -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:806 , http://hdl.handle.net/10962/d1006972
- Description: This research was initiated due to declining customer satisfaction indices in the Southern region of Eskom, an electricity utility in South Africa. Given the link between customer satisfaction and purchase intentions, the sustainability of the business is at stake. The validity of the current MaxiCare survey tool is questioned and explored, as is the congruence of management and customers' perceptions regarding the key service quality constructs in the industry. The study's objective was to provide management with a reliable and valid customer satisfaction survey instrument as an alternate to the existing tool and to use the knowledge gained through the research process to recommend improvement strategies aimed at closing specific satisfaction gaps identified. The research was performed in two stages; firstly, semistructured interviews with customers and management to gain an understanding of the most important satisfaction dimensions. These influenced the design of a survey instrument based largely on the SERVPERF tool with the inclusion of importance ratings per item in the second stage. The quantitative survey results were used to assess the reliability and validity of the research and to suggest areas for future work. The results show that communication, quality of supply, assurance and price are uppermost in the consumer's mind. Tangibles are not significant and the inclusion of empathy is inconclusive. Management and customer perceptions at a macro level are closely aligned, however the two populations are not in agreement as to the underlying micro considerations. Similarly, the MaxiCare instrument is found to be valid as a macro indicator but lacks sufficient detail to be useful as a strategic tool and needs to be supplemented with additional sources of market information. The survey instrument used in the second phase is both descriptive and reliable but the number of factors it measures, the mix of items and the inclusion of the 'importance' dimension need further refinement to improve its validity. Future revisions of the tool will provide management with specific information that allows them to focus improvement strategies on disgruntled customers and their key service issues.
- Full Text:
- Date Issued: 2004
- Authors: MacColl, Barry
- Date: 2004
- Subjects: Eskom (Firm) Electric power distribution -- Customer services -- South Africa -- Eastern Cape Electric power distribution -- South Africa -- Eastern Cape -- Quality control Customer services -- Quality control Customer services -- Rating of -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:806 , http://hdl.handle.net/10962/d1006972
- Description: This research was initiated due to declining customer satisfaction indices in the Southern region of Eskom, an electricity utility in South Africa. Given the link between customer satisfaction and purchase intentions, the sustainability of the business is at stake. The validity of the current MaxiCare survey tool is questioned and explored, as is the congruence of management and customers' perceptions regarding the key service quality constructs in the industry. The study's objective was to provide management with a reliable and valid customer satisfaction survey instrument as an alternate to the existing tool and to use the knowledge gained through the research process to recommend improvement strategies aimed at closing specific satisfaction gaps identified. The research was performed in two stages; firstly, semistructured interviews with customers and management to gain an understanding of the most important satisfaction dimensions. These influenced the design of a survey instrument based largely on the SERVPERF tool with the inclusion of importance ratings per item in the second stage. The quantitative survey results were used to assess the reliability and validity of the research and to suggest areas for future work. The results show that communication, quality of supply, assurance and price are uppermost in the consumer's mind. Tangibles are not significant and the inclusion of empathy is inconclusive. Management and customer perceptions at a macro level are closely aligned, however the two populations are not in agreement as to the underlying micro considerations. Similarly, the MaxiCare instrument is found to be valid as a macro indicator but lacks sufficient detail to be useful as a strategic tool and needs to be supplemented with additional sources of market information. The survey instrument used in the second phase is both descriptive and reliable but the number of factors it measures, the mix of items and the inclusion of the 'importance' dimension need further refinement to improve its validity. Future revisions of the tool will provide management with specific information that allows them to focus improvement strategies on disgruntled customers and their key service issues.
- Full Text:
- Date Issued: 2004
Small town South Africa: the historical geography of selected Eastern Cape towns and current development initiatives within them
- White, Richard Charles Crookes
- Authors: White, Richard Charles Crookes
- Date: 2004 , 2013-06-03
- Subjects: Cities and towns -- South Africa -- Eastern Cape -- Growth , Cities and towns -- South Africa -- Population -- Statistics , Economic development -- South Africa -- Eastern Cape , Community development -- South Africa -- Eastern Cape , Eastern Cape (South Africa) -- History , Eastern Cape (South Africa) -- Economic conditions , Eastern Cape (South Africa) -- Social conditions
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:4805 , http://hdl.handle.net/10962/d1003288 , Cities and towns -- South Africa -- Eastern Cape -- Growth , Cities and towns -- South Africa -- Population -- Statistics , Economic development -- South Africa -- Eastern Cape , Community development -- South Africa -- Eastern Cape , Eastern Cape (South Africa) -- History , Eastern Cape (South Africa) -- Economic conditions , Eastern Cape (South Africa) -- Social conditions
- Description: Small towns can be seen as the fundamental building blocks of tbe urban system. Through time, some of these towns have lost the primary reason for their existence. Some towns that have been declining or stagnating include old mining and industrial towns, such as Indwe in the Eastern Cape or Welkom in the Free State. Some towns have also changed the main focus of tbeir economy, for example, from that of mining to that of tourism, as in the case of Utrecht in Kwa-Zulu Natal (Nel, 2002). In light of the above, this thesis seeks to critically evaluate what has happened in selected small towns in the Eastern Cape. The research investigated a number of towns in the Eastern Cape, looking at the history and influence of colonisation, population dynamics, education levels, employment opportunities, migration and the influence of capitalism on the economic and social structure of the town, as well as tbe evolution of its economy. The research sample consisted of interviews witb local historians, community leaders, development agencies and individuals who were benefiting from tbe various development initiatives/project in the towns. These interviews, in conjunction with the literature identified, were conducted in the selected small towns, assessing whether development was succeeding and, in conclusion, identifying witb reference to the study sites, what was learnt. The research process generated a number of lessons that need to be taken into consideration when attempting social and economic upliftment in small towns. These include: the need for leadership, support from the local population and the need for financial assistance to support and uplift the community. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Date Issued: 2004
- Authors: White, Richard Charles Crookes
- Date: 2004 , 2013-06-03
- Subjects: Cities and towns -- South Africa -- Eastern Cape -- Growth , Cities and towns -- South Africa -- Population -- Statistics , Economic development -- South Africa -- Eastern Cape , Community development -- South Africa -- Eastern Cape , Eastern Cape (South Africa) -- History , Eastern Cape (South Africa) -- Economic conditions , Eastern Cape (South Africa) -- Social conditions
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:4805 , http://hdl.handle.net/10962/d1003288 , Cities and towns -- South Africa -- Eastern Cape -- Growth , Cities and towns -- South Africa -- Population -- Statistics , Economic development -- South Africa -- Eastern Cape , Community development -- South Africa -- Eastern Cape , Eastern Cape (South Africa) -- History , Eastern Cape (South Africa) -- Economic conditions , Eastern Cape (South Africa) -- Social conditions
- Description: Small towns can be seen as the fundamental building blocks of tbe urban system. Through time, some of these towns have lost the primary reason for their existence. Some towns that have been declining or stagnating include old mining and industrial towns, such as Indwe in the Eastern Cape or Welkom in the Free State. Some towns have also changed the main focus of tbeir economy, for example, from that of mining to that of tourism, as in the case of Utrecht in Kwa-Zulu Natal (Nel, 2002). In light of the above, this thesis seeks to critically evaluate what has happened in selected small towns in the Eastern Cape. The research investigated a number of towns in the Eastern Cape, looking at the history and influence of colonisation, population dynamics, education levels, employment opportunities, migration and the influence of capitalism on the economic and social structure of the town, as well as tbe evolution of its economy. The research sample consisted of interviews witb local historians, community leaders, development agencies and individuals who were benefiting from tbe various development initiatives/project in the towns. These interviews, in conjunction with the literature identified, were conducted in the selected small towns, assessing whether development was succeeding and, in conclusion, identifying witb reference to the study sites, what was learnt. The research process generated a number of lessons that need to be taken into consideration when attempting social and economic upliftment in small towns. These include: the need for leadership, support from the local population and the need for financial assistance to support and uplift the community. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Date Issued: 2004
Sobriety of crisp and fuzzy topological spaces
- Authors: Jacot-Guillarmod, Paul
- Date: 2004
- Subjects: Topological spaces , Fuzzy sets
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5414 , http://hdl.handle.net/10962/d1005228 , Topological spaces , Fuzzy sets
- Description: The objective of this thesis is a survey of crisp and fuzzy sober topological spaces. We begin by examining sobriety of crisp topological spaces. We then extend this to the L- topological case and obtain analogous results and characterizations to those of the crisp case. We then brie y examine semi-sobriety of (L;M)-topological spaces.
- Full Text:
- Date Issued: 2004
- Authors: Jacot-Guillarmod, Paul
- Date: 2004
- Subjects: Topological spaces , Fuzzy sets
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5414 , http://hdl.handle.net/10962/d1005228 , Topological spaces , Fuzzy sets
- Description: The objective of this thesis is a survey of crisp and fuzzy sober topological spaces. We begin by examining sobriety of crisp topological spaces. We then extend this to the L- topological case and obtain analogous results and characterizations to those of the crisp case. We then brie y examine semi-sobriety of (L;M)-topological spaces.
- Full Text:
- Date Issued: 2004
Spirituality in the fiction of Henry Rider Haggard
- Authors: Senior, John
- Date: 2004
- Subjects: Haggard, H. Rider (Henry Rider), 1856-1925 -- Religion Haggard, H. Rider (Henry Rider), 1856-1925 -- Criticism and interpretation Religion in literature Spirituality in literature
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2209 , http://hdl.handle.net/10962/d1002252
- Description: Neither an unquestioning support for British imperialism nor a personal pre-Jungian philosophy were the driving forces behind Rider Haggard’s beliefs or his literature. These two concerns were secondary to the author’s fascination with the supernatural, a theme prominent in his era, but less so in our own. A declining faith in European religion provided the dominant focal point in Haggard’s work. Although there are important overtones of imperial concern and indeed points of Jungian significance in the texts, these are generally subservient to an intensive wide-ranging spiritual discourse. The place of Haggard’s work in history and its literary merit are thus misunderstood when his spiritualism is not taken into account. No analysis of the author’s work can be complete without first coming to terms with his spiritual ideas and then with their impact on other topics of significance to both the author and audiences of his day. The spiritual or religious aspect of his writing has been largely ignored because of its subtle nature and its relative unfashionability throughout most of the twentieth century in the critical and intellectual climate of the Western world. However, in the Victorian era, under the materialist impact of Darwin, Marx and industrialization, Europe's Christian God was pushed from centre stage, creating widespread spiritual hunger and anguish. In the resulting religious vacuum Haggard's overtures were of particular significance to his audience. In fact, when considered in terms of his immense contemporary popularity, the pervasive presence of spirituality throughout Haggard's works and in his personal writing gives some indication of the subject's enormous importance not only to the author, but to late Victorian society as a whole. In light of this Victorian significance, the spiritual element rises, by its constant presence and persistent foregrounding, to subvert not only the imperial and the Jungian, but even Haggard's overt adventure text by dealing directly with the underlying metaphysical crisis in Western society.
- Full Text:
- Date Issued: 2004
- Authors: Senior, John
- Date: 2004
- Subjects: Haggard, H. Rider (Henry Rider), 1856-1925 -- Religion Haggard, H. Rider (Henry Rider), 1856-1925 -- Criticism and interpretation Religion in literature Spirituality in literature
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2209 , http://hdl.handle.net/10962/d1002252
- Description: Neither an unquestioning support for British imperialism nor a personal pre-Jungian philosophy were the driving forces behind Rider Haggard’s beliefs or his literature. These two concerns were secondary to the author’s fascination with the supernatural, a theme prominent in his era, but less so in our own. A declining faith in European religion provided the dominant focal point in Haggard’s work. Although there are important overtones of imperial concern and indeed points of Jungian significance in the texts, these are generally subservient to an intensive wide-ranging spiritual discourse. The place of Haggard’s work in history and its literary merit are thus misunderstood when his spiritualism is not taken into account. No analysis of the author’s work can be complete without first coming to terms with his spiritual ideas and then with their impact on other topics of significance to both the author and audiences of his day. The spiritual or religious aspect of his writing has been largely ignored because of its subtle nature and its relative unfashionability throughout most of the twentieth century in the critical and intellectual climate of the Western world. However, in the Victorian era, under the materialist impact of Darwin, Marx and industrialization, Europe's Christian God was pushed from centre stage, creating widespread spiritual hunger and anguish. In the resulting religious vacuum Haggard's overtures were of particular significance to his audience. In fact, when considered in terms of his immense contemporary popularity, the pervasive presence of spirituality throughout Haggard's works and in his personal writing gives some indication of the subject's enormous importance not only to the author, but to late Victorian society as a whole. In light of this Victorian significance, the spiritual element rises, by its constant presence and persistent foregrounding, to subvert not only the imperial and the Jungian, but even Haggard's overt adventure text by dealing directly with the underlying metaphysical crisis in Western society.
- Full Text:
- Date Issued: 2004
Studies on parasitoids of the diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), in South Africa
- Authors: Nofemela, Sicelo Robert
- Date: 2004
- Subjects: Plutellidae -- South Africa , Plutellidae -- Biological control , Plutellidae -- Parasites , Parasitoids
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5780 , http://hdl.handle.net/10962/d1005468 , Plutellidae -- South Africa , Plutellidae -- Biological control , Plutellidae -- Parasites , Parasitoids
- Description: The diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), is a major pest of Brassica crops in many parts of the world. Because of its ability to develop resistance to virtually all major groups of insecticides, including Bacillus thuringiensis Berliner (Bt), much attention has therefore been given to biological control using parasitoids. South Africa has an abundance of parasitoids attacking this pest. Cotesia plutellae (Kurdjumov) (Hymenoptera: Braconidae) is the most abundant larval parasitoid of P. xylostella in South Africa. In East Africa, its role in biological control of P. xylostella is insignificant, and the most abundant parasitoid there is Diadegma mollipla (Holmgren) (Hymenoptera: Ichneumonidae), a larvalpupal parasitoid. In South Africa, however, D. mollipla is out-competed by C. plutellae. Total parasitism of P. xylostella in East Africa rarely exceeds 15%, therefore there is a need to introduce more effective and heat-tolerant parasitoids of P. xylostella to that region. This study was therefore initiated to examine the potential of C. plutellae and D. mollipla as biological control agents by studying certain aspects of their biology in the laboratory, as well as the suitability of C. plutellae for introduction into East Africa. Biological aspects studied were: (i) host instar preference, fecundity, and searching efficiency of C. plutellae and D. mollipla at different host and parasitoid densities; (ii) effects of temperature on parasitism of P. xylostella by C. plutellae and D. mollipla, and on their rates of development and emergence. In addition, the role of parasitoids in controlling P. xylostella on unsprayed cabbage plots was investigated. Both C. plutellae and D. mollipla preferred to attack second and third instar hosts than fourth instars in choice and no-choice tests. However, D. mollipla attacked more fourth instar hosts than C. plutellae. Cotesia plutellae laid mainly female eggs in second and third instar hosts than in fourth instars, whereas D. mollipla laid more female eggs in fourth instar hosts than in second and third instar hosts. Diadegma mollipla was more fecund [82.57 ± 32.87, (mean ± s.d.) than C. plutellae (42.13 ± 12.2), and was long lived (7.13 ± 3.69 days) compared to the latter (5.23 ± 2.7 days). An increase in host density resulted in the reduction in the area of discovery (a) and the killing power (K) for both parasitoids. No significant differences were detected between the searching efficiency (t = -1.42NS, d.f. = 48, P < 0.001) of the two parasitoids. An increase in parasitoid density also resulted in a decline in searching efficiency, but not the killing power, of both parasitoids. Cotesia plutellae completed development at all temperatures tested (21-33°C), whereas D. mollipla completed development at temperatures from 18-30°C, and C. plutellae had a lower threshold for development (8.14°C) compared to D. mollipla (10.23°C). At all tested temperatures, the generation time for C. plutellae was shorter compared to D. mollipla. The possible reasons for the dominance of C. plutellae over D. mollipla in the field are: shorter generation time, high production of female progeny in younger hosts, low interference among searching females, and relatively wide thermal tolerance. The role of parasitoids in regulating diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), populations was studied for two years (February 2000-January 2002) on unsprayed cabbage fields at Brits, North West Province, South Africa. Cabbage seedlings were transplanted in three consecutive times each year. Cabbage infestations by P. xylostella larvae and pupae, and their parasitoids, were monitored at weekly intervals. The flight activity of P. xylostella male moths was monitored using sex-pheromone traps. Trap catches indicated that the moths were active throughout the year. The flight activity of the moths corresponded with infestations on the crop. Trap catches and infestation levels were generally low from December to August and high from September to November. Eight hymenopteran parasitoids were reared: the larval parasitoids Cotesia plutellae (Kurdjumov) (Braconidae) and Apanteles halfordi (Ullyett) (Braconidae); the larval-pupal parasitoids Oomyzus sokolowskii (Kurdjumov) (Eulophidae) and Diadegma mollipla (Holmgren)(Ichneumonidae); the pupal parasitoid Diadromus collaris (Gravenhorst) (Ichneumonidae); and the hyperparasitoids Eurytoma sp. (Eurytomidae), Mesochorus sp. (Ichneumonidae), and Pteromalus sp. (Pteromalidae). Cotesia plutellae was the most abundant parasitoid of P. xylostella followed by O. sokolowskii, D. collaris, A. halfordi and D. mollipla. Parasitism of P. xylostella larvae was high reaching 100% on several occasions during late spring to end of autumn (November-May) each year. Parasitism was lower (<50%) in winter and early spring (June-September). Apanteles halfordi was absent in winter but re-appeared in spring. Parasitism of P. xylostella pupae by D. collaris was high only during spring (September-October). Hyperparasitism was generally low except when primary parasitoids were abundant in spring (September-November) and summer (December-February) when up to 25% of P. xylostella larvae and C. plutellae cocoons yielded hyperparasitoids. The role of other biotic and abiotic mortality factors on the population dynamics of P. xylostella is discussed.
- Full Text:
- Date Issued: 2004
- Authors: Nofemela, Sicelo Robert
- Date: 2004
- Subjects: Plutellidae -- South Africa , Plutellidae -- Biological control , Plutellidae -- Parasites , Parasitoids
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5780 , http://hdl.handle.net/10962/d1005468 , Plutellidae -- South Africa , Plutellidae -- Biological control , Plutellidae -- Parasites , Parasitoids
- Description: The diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), is a major pest of Brassica crops in many parts of the world. Because of its ability to develop resistance to virtually all major groups of insecticides, including Bacillus thuringiensis Berliner (Bt), much attention has therefore been given to biological control using parasitoids. South Africa has an abundance of parasitoids attacking this pest. Cotesia plutellae (Kurdjumov) (Hymenoptera: Braconidae) is the most abundant larval parasitoid of P. xylostella in South Africa. In East Africa, its role in biological control of P. xylostella is insignificant, and the most abundant parasitoid there is Diadegma mollipla (Holmgren) (Hymenoptera: Ichneumonidae), a larvalpupal parasitoid. In South Africa, however, D. mollipla is out-competed by C. plutellae. Total parasitism of P. xylostella in East Africa rarely exceeds 15%, therefore there is a need to introduce more effective and heat-tolerant parasitoids of P. xylostella to that region. This study was therefore initiated to examine the potential of C. plutellae and D. mollipla as biological control agents by studying certain aspects of their biology in the laboratory, as well as the suitability of C. plutellae for introduction into East Africa. Biological aspects studied were: (i) host instar preference, fecundity, and searching efficiency of C. plutellae and D. mollipla at different host and parasitoid densities; (ii) effects of temperature on parasitism of P. xylostella by C. plutellae and D. mollipla, and on their rates of development and emergence. In addition, the role of parasitoids in controlling P. xylostella on unsprayed cabbage plots was investigated. Both C. plutellae and D. mollipla preferred to attack second and third instar hosts than fourth instars in choice and no-choice tests. However, D. mollipla attacked more fourth instar hosts than C. plutellae. Cotesia plutellae laid mainly female eggs in second and third instar hosts than in fourth instars, whereas D. mollipla laid more female eggs in fourth instar hosts than in second and third instar hosts. Diadegma mollipla was more fecund [82.57 ± 32.87, (mean ± s.d.) than C. plutellae (42.13 ± 12.2), and was long lived (7.13 ± 3.69 days) compared to the latter (5.23 ± 2.7 days). An increase in host density resulted in the reduction in the area of discovery (a) and the killing power (K) for both parasitoids. No significant differences were detected between the searching efficiency (t = -1.42NS, d.f. = 48, P < 0.001) of the two parasitoids. An increase in parasitoid density also resulted in a decline in searching efficiency, but not the killing power, of both parasitoids. Cotesia plutellae completed development at all temperatures tested (21-33°C), whereas D. mollipla completed development at temperatures from 18-30°C, and C. plutellae had a lower threshold for development (8.14°C) compared to D. mollipla (10.23°C). At all tested temperatures, the generation time for C. plutellae was shorter compared to D. mollipla. The possible reasons for the dominance of C. plutellae over D. mollipla in the field are: shorter generation time, high production of female progeny in younger hosts, low interference among searching females, and relatively wide thermal tolerance. The role of parasitoids in regulating diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), populations was studied for two years (February 2000-January 2002) on unsprayed cabbage fields at Brits, North West Province, South Africa. Cabbage seedlings were transplanted in three consecutive times each year. Cabbage infestations by P. xylostella larvae and pupae, and their parasitoids, were monitored at weekly intervals. The flight activity of P. xylostella male moths was monitored using sex-pheromone traps. Trap catches indicated that the moths were active throughout the year. The flight activity of the moths corresponded with infestations on the crop. Trap catches and infestation levels were generally low from December to August and high from September to November. Eight hymenopteran parasitoids were reared: the larval parasitoids Cotesia plutellae (Kurdjumov) (Braconidae) and Apanteles halfordi (Ullyett) (Braconidae); the larval-pupal parasitoids Oomyzus sokolowskii (Kurdjumov) (Eulophidae) and Diadegma mollipla (Holmgren)(Ichneumonidae); the pupal parasitoid Diadromus collaris (Gravenhorst) (Ichneumonidae); and the hyperparasitoids Eurytoma sp. (Eurytomidae), Mesochorus sp. (Ichneumonidae), and Pteromalus sp. (Pteromalidae). Cotesia plutellae was the most abundant parasitoid of P. xylostella followed by O. sokolowskii, D. collaris, A. halfordi and D. mollipla. Parasitism of P. xylostella larvae was high reaching 100% on several occasions during late spring to end of autumn (November-May) each year. Parasitism was lower (<50%) in winter and early spring (June-September). Apanteles halfordi was absent in winter but re-appeared in spring. Parasitism of P. xylostella pupae by D. collaris was high only during spring (September-October). Hyperparasitism was generally low except when primary parasitoids were abundant in spring (September-November) and summer (December-February) when up to 25% of P. xylostella larvae and C. plutellae cocoons yielded hyperparasitoids. The role of other biotic and abiotic mortality factors on the population dynamics of P. xylostella is discussed.
- Full Text:
- Date Issued: 2004
The adaptive development and use of learning support materials in response to the 1st principle of the revised national curriculum statement : the case of Hadeda Island
- Authors: Olvitt, Lausanne Laura
- Date: 2004
- Subjects: Environmental education -- South Africa -- Case studies Environmental education -- Curricula -- South Africa Teaching -- Aids and devices -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1938 , http://hdl.handle.net/10962/d1007719
- Description: This case study describes the development and trial use of the Hadeda Island Big Book. Developed within a transforming South African curriculum framework, the study recognises that current educational practices are shaped and steered by historical, cultural, political and economic realities. This perspective guides the research design, which considers each of the three participating schools as contextually unique. The Hadeda Island Big Book was developed in response to the 1st Principle of the Revised National Curriculum Statement (RNCS). This calls for all curriculum activities to develop learners' understandings of the relationship between social justice, a healthy environment, human rights and inclusivity. The study probes ways in which learning support materials might respond in line with the vision of the RNCS 1st Principle. Associated challenges, tensions and opportunities are discussed in relation to schools' interactions with the Hadeda Island Big Book. The diverse and creative responses to the book lead this study to foreground generative approaches to curriculum work. Emphasis is thus redirected from hierarchical, stipulative views of curriculum to more dynamic, responsive views of curriculum as a guiding framework. This is regarded as a valuable orientation to the development of future learning support materials. The study comments on the challenge of supporting teachers to develop curriculum activities that reflect a view of 'environment' as socially shaped and multi-dimensional. Tendencies to focus on either the 'ecological' or the 'social' dimensions of environmental issues rather than on the interacting socio-ecological dimensions are recognised as limiting the material's potential to strengthen environmental learning in schools. The study recommends that greater attention be paid to the environmentally-oriented Learning Outcomes and Assessment Standards of all Learning Areas in the RNCS. In so doing, socio-ecological learning processes may be strengthened through curriculum work.
- Full Text:
- Date Issued: 2004
- Authors: Olvitt, Lausanne Laura
- Date: 2004
- Subjects: Environmental education -- South Africa -- Case studies Environmental education -- Curricula -- South Africa Teaching -- Aids and devices -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1938 , http://hdl.handle.net/10962/d1007719
- Description: This case study describes the development and trial use of the Hadeda Island Big Book. Developed within a transforming South African curriculum framework, the study recognises that current educational practices are shaped and steered by historical, cultural, political and economic realities. This perspective guides the research design, which considers each of the three participating schools as contextually unique. The Hadeda Island Big Book was developed in response to the 1st Principle of the Revised National Curriculum Statement (RNCS). This calls for all curriculum activities to develop learners' understandings of the relationship between social justice, a healthy environment, human rights and inclusivity. The study probes ways in which learning support materials might respond in line with the vision of the RNCS 1st Principle. Associated challenges, tensions and opportunities are discussed in relation to schools' interactions with the Hadeda Island Big Book. The diverse and creative responses to the book lead this study to foreground generative approaches to curriculum work. Emphasis is thus redirected from hierarchical, stipulative views of curriculum to more dynamic, responsive views of curriculum as a guiding framework. This is regarded as a valuable orientation to the development of future learning support materials. The study comments on the challenge of supporting teachers to develop curriculum activities that reflect a view of 'environment' as socially shaped and multi-dimensional. Tendencies to focus on either the 'ecological' or the 'social' dimensions of environmental issues rather than on the interacting socio-ecological dimensions are recognised as limiting the material's potential to strengthen environmental learning in schools. The study recommends that greater attention be paid to the environmentally-oriented Learning Outcomes and Assessment Standards of all Learning Areas in the RNCS. In so doing, socio-ecological learning processes may be strengthened through curriculum work.
- Full Text:
- Date Issued: 2004
The development of a geographic information system (GIS) as a mariculture sector planning tool in South Africa
- Authors: Shiran-Klotz, Imran
- Date: 2004
- Subjects: Geographic information systems -- South Africa , Fishery management -- Geographic information systems -- South Africa , Mariculture -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5337 , http://hdl.handle.net/10962/d1005870 , Geographic information systems -- South Africa , Fishery management -- Geographic information systems -- South Africa , Mariculture -- South Africa
- Description: The South African coastline has a high potential for mariculture development, particularly in land-based systems, due to excellent water quality, good infrastructure, and relatively cheap land in certain areas. Development of mariculture however, has been slow primarily due to the absence of a national sector development plan to coordinate contribution to development by government, industry and academia. Recent mariculture development plans however, supported by government commitment to stimulate coastal development, offers new opportunity for the sector's growth. These new sector development plans require a multi-disciplinary intensive information base with a strong regional and national spatial component. Geographic Information System (GIS) is a spatial analytical tool, which is capable of handling such large coastal databases and analysing them. Nevertheless, many mariculture GIS planning applications, often developed in isolation and with limited practical use for decision makers, highlighted the need to develop GIS in relation to the mariculture sector development plan. Hence, the aim of this study was to develop and evaluate a GIS for the national and regional mariculture sector planning process in South Africa, in order to identify potentially suitable areas along the South African coastline for mariculture operations. The GIS development in this study was based on the mariculture planning approach developed by PAP/RAe (1996), which recognizes the variations of scales in mariculture planning. Three case studies, representing the diversity of the South African sector plan, were selected to develop the GIS. They included: a national suitability analysis for all land-based culture systems, a specific national analysis on abalone ranching, and a detailed regional analysis of land-based culture and abalone ranching along the Namaqualand coastline. The GIS was developed separately for each case study based on a strategy consisting of six main phases, including: identification of project requirements, developing analytical framework, selection and location of data sources, organization and manipulation of data, analysing data and verifying and evaluation of the outputs. Biophysical, coastal use, and infrastructure criteria were collected, sorted and analysed to identify development constraints. Based on a set of conditions, and Boolean logic and arithmetic operations, unsuitable areas were identified and eliminated. Main constraints for national land-based development included competition over space along KwaZuluNatal Province coastline and restricted access to the coast along the south region of the Northern Cape Province, Wild Coast along the Eastern Cape Province, and Maputaland along KwaZulu-Natal Province. Ten areas along the country coastline were therefore identified as potentially suitable for land-based mariculture. Furthermore, South African abalone ranching potential was found to be limited mostly along the Western and Northern Cape Province's coastline due to the high risk of Paralytic Shellfish Poison (PSP) occurrences, alternative resource use and activities such as commercial fishery, poaching, and conservation. Hence, a total of nine areas along the Northern Cape, Western Cape, and Eastern Cape coastlines were identified as premier areas for abalone ranching. The regional study along the Namaqualand coastline revealed potential conflict between mining activity and mariculture development due to security issues and restricted access to the coast. Land-based mariculture development was confined to the four main coastal urban areas. The highest potential for land-based mariculture was along Port Nolloth and Kleinsee coastlines, whereas marine-based (i.e. abalone ranching) potential was poor along the north part of the coast due to intense marine mining activities, restricted access to the coast, and low kelp bed density. High potential abalone ranching areas were identified south to Kleinsee, and around Port Nolloth. Potential conflict with marine mining activity was minimal since it was localised and not related to kelp bed locations. It was concluded that GIS is a relevant and compatible tool for South African mariculture sector planning. However, future development of GIS as integrated planning tool in mariculture and coastal planning, requires updated spatial data (e.g. recreational activity), and continued interaction among project planners, mariculture specialists and GIS analysts.
- Full Text:
- Date Issued: 2004
- Authors: Shiran-Klotz, Imran
- Date: 2004
- Subjects: Geographic information systems -- South Africa , Fishery management -- Geographic information systems -- South Africa , Mariculture -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5337 , http://hdl.handle.net/10962/d1005870 , Geographic information systems -- South Africa , Fishery management -- Geographic information systems -- South Africa , Mariculture -- South Africa
- Description: The South African coastline has a high potential for mariculture development, particularly in land-based systems, due to excellent water quality, good infrastructure, and relatively cheap land in certain areas. Development of mariculture however, has been slow primarily due to the absence of a national sector development plan to coordinate contribution to development by government, industry and academia. Recent mariculture development plans however, supported by government commitment to stimulate coastal development, offers new opportunity for the sector's growth. These new sector development plans require a multi-disciplinary intensive information base with a strong regional and national spatial component. Geographic Information System (GIS) is a spatial analytical tool, which is capable of handling such large coastal databases and analysing them. Nevertheless, many mariculture GIS planning applications, often developed in isolation and with limited practical use for decision makers, highlighted the need to develop GIS in relation to the mariculture sector development plan. Hence, the aim of this study was to develop and evaluate a GIS for the national and regional mariculture sector planning process in South Africa, in order to identify potentially suitable areas along the South African coastline for mariculture operations. The GIS development in this study was based on the mariculture planning approach developed by PAP/RAe (1996), which recognizes the variations of scales in mariculture planning. Three case studies, representing the diversity of the South African sector plan, were selected to develop the GIS. They included: a national suitability analysis for all land-based culture systems, a specific national analysis on abalone ranching, and a detailed regional analysis of land-based culture and abalone ranching along the Namaqualand coastline. The GIS was developed separately for each case study based on a strategy consisting of six main phases, including: identification of project requirements, developing analytical framework, selection and location of data sources, organization and manipulation of data, analysing data and verifying and evaluation of the outputs. Biophysical, coastal use, and infrastructure criteria were collected, sorted and analysed to identify development constraints. Based on a set of conditions, and Boolean logic and arithmetic operations, unsuitable areas were identified and eliminated. Main constraints for national land-based development included competition over space along KwaZuluNatal Province coastline and restricted access to the coast along the south region of the Northern Cape Province, Wild Coast along the Eastern Cape Province, and Maputaland along KwaZulu-Natal Province. Ten areas along the country coastline were therefore identified as potentially suitable for land-based mariculture. Furthermore, South African abalone ranching potential was found to be limited mostly along the Western and Northern Cape Province's coastline due to the high risk of Paralytic Shellfish Poison (PSP) occurrences, alternative resource use and activities such as commercial fishery, poaching, and conservation. Hence, a total of nine areas along the Northern Cape, Western Cape, and Eastern Cape coastlines were identified as premier areas for abalone ranching. The regional study along the Namaqualand coastline revealed potential conflict between mining activity and mariculture development due to security issues and restricted access to the coast. Land-based mariculture development was confined to the four main coastal urban areas. The highest potential for land-based mariculture was along Port Nolloth and Kleinsee coastlines, whereas marine-based (i.e. abalone ranching) potential was poor along the north part of the coast due to intense marine mining activities, restricted access to the coast, and low kelp bed density. High potential abalone ranching areas were identified south to Kleinsee, and around Port Nolloth. Potential conflict with marine mining activity was minimal since it was localised and not related to kelp bed locations. It was concluded that GIS is a relevant and compatible tool for South African mariculture sector planning. However, future development of GIS as integrated planning tool in mariculture and coastal planning, requires updated spatial data (e.g. recreational activity), and continued interaction among project planners, mariculture specialists and GIS analysts.
- Full Text:
- Date Issued: 2004
The doctrine of duress in the law of contract and unjustified enrichment in South Africa
- Authors: Glover, Graham Brian
- Date: 2004
- Subjects: Contracts -- South Africa , Duress (Law) -- South Africa , Remedies (Law) -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3672 , http://hdl.handle.net/10962/d1003187 , Contracts -- South Africa , Duress (Law) -- South Africa , Remedies (Law) -- South Africa
- Description: This thesis analyses the doctrine of duress and its application in the law of contract and unjustified enrichment in South Africa. Following an initial examination of the historical development of the doctrine from its roots in Roman and Roman-Dutch law, the study focuses on the current legal position in the two areas of law under review, identifies the substantive and formal deficiencies in the current approach, and suggests, using comparative authorities, how the law might be developed. As far as the law of contract is concerned, after exposing the difficulties inherent in the current approach, and placing the doctrine in its proper context in the South African law of contract generally, it is argued that the duress doctrine finds its juridical basis in the principle of good faith. A more modern and coherent test for duress is then proposed: one that concentrates on the question whether an illegitimate threat was made, which induced a contract in that it left the other person no reasonable choice but to succumb to the proposal. Additionally, the need for South African contract law to recognise and deal with cases of economic duress is emphasised. The study then shifts to an examination of the position in situations where non-contractual performances have occurred under duress: cases that are decided in terms of the principles of the law of unjustified enrichment. The current position is reviewed, and it is shown that the approach to duress cases is substantially different to the approach that applies in contract. An attempt is made to reconcile this problem. From a structural perspective, the nature and application of the relevant enrichment action where a non-contractual performance is made under duress (the condictio indebiti) is also investigated, in the light of approaches to enrichment adopted in both Germany and England, in an attempt to make better sense of this enrichment action in the South African context. The study closes with an analysis of the various contractual, delictual and enrichment remedies that are available once a case of duress has been proved.
- Full Text:
- Date Issued: 2004
- Authors: Glover, Graham Brian
- Date: 2004
- Subjects: Contracts -- South Africa , Duress (Law) -- South Africa , Remedies (Law) -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3672 , http://hdl.handle.net/10962/d1003187 , Contracts -- South Africa , Duress (Law) -- South Africa , Remedies (Law) -- South Africa
- Description: This thesis analyses the doctrine of duress and its application in the law of contract and unjustified enrichment in South Africa. Following an initial examination of the historical development of the doctrine from its roots in Roman and Roman-Dutch law, the study focuses on the current legal position in the two areas of law under review, identifies the substantive and formal deficiencies in the current approach, and suggests, using comparative authorities, how the law might be developed. As far as the law of contract is concerned, after exposing the difficulties inherent in the current approach, and placing the doctrine in its proper context in the South African law of contract generally, it is argued that the duress doctrine finds its juridical basis in the principle of good faith. A more modern and coherent test for duress is then proposed: one that concentrates on the question whether an illegitimate threat was made, which induced a contract in that it left the other person no reasonable choice but to succumb to the proposal. Additionally, the need for South African contract law to recognise and deal with cases of economic duress is emphasised. The study then shifts to an examination of the position in situations where non-contractual performances have occurred under duress: cases that are decided in terms of the principles of the law of unjustified enrichment. The current position is reviewed, and it is shown that the approach to duress cases is substantially different to the approach that applies in contract. An attempt is made to reconcile this problem. From a structural perspective, the nature and application of the relevant enrichment action where a non-contractual performance is made under duress (the condictio indebiti) is also investigated, in the light of approaches to enrichment adopted in both Germany and England, in an attempt to make better sense of this enrichment action in the South African context. The study closes with an analysis of the various contractual, delictual and enrichment remedies that are available once a case of duress has been proved.
- Full Text:
- Date Issued: 2004
The ecology and control of small hive beetles (Aethina tumida Murray)
- Authors: Ellis, James Douglas
- Date: 2004
- Subjects: Bee culture , Bee culture -- United States , Nitidulidae , Beetles -- Ecology , Beetles -- Control
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5917 , http://hdl.handle.net/10962/d1016253
- Description: The small hive beetle (Aethina tumida Murray) is an endemic scavenger in colonies of honey bee (Apis mellifera L.) subspecies inhabiting sub-Saharan Africa. The beetle only occasionally damages host colonies in its native range and such damage is usually restricted to weakened/diseased colonies or is associated with after absconding events due to behavioral resistance mechanisms of its host. The beetle has recently been introduced into North America and Australia where populations of managed subspecies of European honey bees have proven highly susceptible to beetle depredation. Beetles are able to reproduce in large numbers in European colonies and their larvae weaken colonies by eating honey, pollen, and bee brood. Further, adult and larval defecation is thought to promote the fermentation of honey and large populations of beetles can cause European colonies to abscond, both resulting in additional colony damage. The economic losses attributed to the beetle since its introduction into the United States have been estimated in millions of US dollars. Although beetles feed on foodstuffs found within colonies, experiments in vitro show that they can also complete entire life cycles on fruit. Regardless, they reproduce best on diets of honey, pollen, and bee brood. After feeding, beetle larvae exit the colony and burrow into the ground where they pupate. Neither soil type nor density affects a beetle’s ability to successfully pupate. Instead, successful pupation appears to be closely tied to soil moisture. African subspecies of honey bees employ a complicated scheme of confinement (aggressive behavior toward and guarding of beetles) to limit beetle reproduction in a colony. Despite being confined away from food, adult beetles are able to solicit food and feed from the mouths of their honey bee guards. Remarkably, beetle-naïve European honey bees also confine beetles and this behavior is quantitatively similar to that in African bees. If confinement efforts fail, beetles access the combs where they feed and reproduce. Two modes of beetle oviposition in sealed bee brood have been identified. In the first mode, beetles bite holes in the cappings of cells and oviposit on the pupa contained within. In the second mode, beetles enter empty cells, bite a hole in the wall of the cell, and oviposit on the brood in the adjacent cell. Despite this, African bees detect and remove all of the infected brood (hygienic behavior). Similarly, European bees can detect and remove brood that has been oviposited on by beetles. Enhancing the removal rate of infected brood in European colonies through selective breeding may achieve genetic control of beetles. Additional avenues of control were tested for efficacy against beetles. Reducing colony entrances slowed beetle ingress but the efficacy of this method probably depends on other factors. Further, the mortality of beetle pupae was higher when contacting species of the fungus Aspergillus than when not, making biological control an option. Regardless, no control tested to date proved efficacious at the level needed by beekeepers so an integrated approach to controlling beetles remains preferred. The amalgamation of the data presented in this dissertation contributed to a discussion on the beetle’s ecological niche, ability to impact honey bee colonies in ways never considered, and the ability to predict the beetle’s spread and impact globally.
- Full Text:
- Date Issued: 2004
- Authors: Ellis, James Douglas
- Date: 2004
- Subjects: Bee culture , Bee culture -- United States , Nitidulidae , Beetles -- Ecology , Beetles -- Control
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5917 , http://hdl.handle.net/10962/d1016253
- Description: The small hive beetle (Aethina tumida Murray) is an endemic scavenger in colonies of honey bee (Apis mellifera L.) subspecies inhabiting sub-Saharan Africa. The beetle only occasionally damages host colonies in its native range and such damage is usually restricted to weakened/diseased colonies or is associated with after absconding events due to behavioral resistance mechanisms of its host. The beetle has recently been introduced into North America and Australia where populations of managed subspecies of European honey bees have proven highly susceptible to beetle depredation. Beetles are able to reproduce in large numbers in European colonies and their larvae weaken colonies by eating honey, pollen, and bee brood. Further, adult and larval defecation is thought to promote the fermentation of honey and large populations of beetles can cause European colonies to abscond, both resulting in additional colony damage. The economic losses attributed to the beetle since its introduction into the United States have been estimated in millions of US dollars. Although beetles feed on foodstuffs found within colonies, experiments in vitro show that they can also complete entire life cycles on fruit. Regardless, they reproduce best on diets of honey, pollen, and bee brood. After feeding, beetle larvae exit the colony and burrow into the ground where they pupate. Neither soil type nor density affects a beetle’s ability to successfully pupate. Instead, successful pupation appears to be closely tied to soil moisture. African subspecies of honey bees employ a complicated scheme of confinement (aggressive behavior toward and guarding of beetles) to limit beetle reproduction in a colony. Despite being confined away from food, adult beetles are able to solicit food and feed from the mouths of their honey bee guards. Remarkably, beetle-naïve European honey bees also confine beetles and this behavior is quantitatively similar to that in African bees. If confinement efforts fail, beetles access the combs where they feed and reproduce. Two modes of beetle oviposition in sealed bee brood have been identified. In the first mode, beetles bite holes in the cappings of cells and oviposit on the pupa contained within. In the second mode, beetles enter empty cells, bite a hole in the wall of the cell, and oviposit on the brood in the adjacent cell. Despite this, African bees detect and remove all of the infected brood (hygienic behavior). Similarly, European bees can detect and remove brood that has been oviposited on by beetles. Enhancing the removal rate of infected brood in European colonies through selective breeding may achieve genetic control of beetles. Additional avenues of control were tested for efficacy against beetles. Reducing colony entrances slowed beetle ingress but the efficacy of this method probably depends on other factors. Further, the mortality of beetle pupae was higher when contacting species of the fungus Aspergillus than when not, making biological control an option. Regardless, no control tested to date proved efficacious at the level needed by beekeepers so an integrated approach to controlling beetles remains preferred. The amalgamation of the data presented in this dissertation contributed to a discussion on the beetle’s ecological niche, ability to impact honey bee colonies in ways never considered, and the ability to predict the beetle’s spread and impact globally.
- Full Text:
- Date Issued: 2004
The effect of commercialisation, privatisation and liberalisation on universal access in South Africa
- Gardner, Sean Patrick Newell
- Authors: Gardner, Sean Patrick Newell
- Date: 2004
- Subjects: Telkom (Firm : South Africa) , Telecommunication , Telecommunication -- South Africa , Privatization -- South Africa , Trade regulation -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3431 , http://hdl.handle.net/10962/d1002885 , Telkom (Firm : South Africa) , Telecommunication , Telecommunication -- South Africa , Privatization -- South Africa , Trade regulation -- South Africa
- Description: From the 1990s onwards, significant developments have occurred in the international telecommunications sector that have affected the South African telecommunications industry and peoples’ access to the network. Rapid developments in Information and Communication Technologies and the reorganisation of telecommunications operators through commercialisation, privatisation and the effects of market liberalisation have resulted in monopoly operators moving away from their public service mandates. Globalisation and adherence to World Trade Organisation rules are causing operators to rebalance their tariffs closer to cost. Long-distance rates are decreasing while the cost of local calls is increasing. High-end users of telecommunications services are benefiting while low-end, largely residential users are being priced off the network. The end result is a negative effect on universal access to telecommunications services. This study examines the extent to which commercialisation, privatisation and liberalization are affecting the provision of telecommunications services and the government’s goal of achieving universal access in South Africa. Qualitative research methods were utilised to establish that the state owned operator, Telkom, has transformed itself from a public service operator to one that is fully commercialised and prepared for an Initial Public Offering and competition. Telkom no longer attempts to ensure that its tariffs are affordable for all people. However, positive developments presented themselves in the form of an increasingly competent regulator, a reorganised and dedicated Universal Service Agency, and the popularity of cellular telephony. The primary discovery of this study is that the liberalisation of the South African telecommunications sector cannot be assumed to have a negative effect on the provision of service. This study finds that liberalisation will most likely benefit the country through the role out of new infrastructure, the provision of new services and ultimately the reduction of those services themselves. In order for universal access to be achieved in this country the study recommends that the resources of the Independent Communications Authority of South Africa be enhanced to enable the regulator oversee the industry effectively. Secondly, the Universal Service Agency must provide clear definitions of universal access and universal service as well as manage the Universal Service Fund with greater efficiency. Lastly, the two bodies mentioned above must ensure that services are affordable for all people of this country.
- Full Text:
- Date Issued: 2004
- Authors: Gardner, Sean Patrick Newell
- Date: 2004
- Subjects: Telkom (Firm : South Africa) , Telecommunication , Telecommunication -- South Africa , Privatization -- South Africa , Trade regulation -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3431 , http://hdl.handle.net/10962/d1002885 , Telkom (Firm : South Africa) , Telecommunication , Telecommunication -- South Africa , Privatization -- South Africa , Trade regulation -- South Africa
- Description: From the 1990s onwards, significant developments have occurred in the international telecommunications sector that have affected the South African telecommunications industry and peoples’ access to the network. Rapid developments in Information and Communication Technologies and the reorganisation of telecommunications operators through commercialisation, privatisation and the effects of market liberalisation have resulted in monopoly operators moving away from their public service mandates. Globalisation and adherence to World Trade Organisation rules are causing operators to rebalance their tariffs closer to cost. Long-distance rates are decreasing while the cost of local calls is increasing. High-end users of telecommunications services are benefiting while low-end, largely residential users are being priced off the network. The end result is a negative effect on universal access to telecommunications services. This study examines the extent to which commercialisation, privatisation and liberalization are affecting the provision of telecommunications services and the government’s goal of achieving universal access in South Africa. Qualitative research methods were utilised to establish that the state owned operator, Telkom, has transformed itself from a public service operator to one that is fully commercialised and prepared for an Initial Public Offering and competition. Telkom no longer attempts to ensure that its tariffs are affordable for all people. However, positive developments presented themselves in the form of an increasingly competent regulator, a reorganised and dedicated Universal Service Agency, and the popularity of cellular telephony. The primary discovery of this study is that the liberalisation of the South African telecommunications sector cannot be assumed to have a negative effect on the provision of service. This study finds that liberalisation will most likely benefit the country through the role out of new infrastructure, the provision of new services and ultimately the reduction of those services themselves. In order for universal access to be achieved in this country the study recommends that the resources of the Independent Communications Authority of South Africa be enhanced to enable the regulator oversee the industry effectively. Secondly, the Universal Service Agency must provide clear definitions of universal access and universal service as well as manage the Universal Service Fund with greater efficiency. Lastly, the two bodies mentioned above must ensure that services are affordable for all people of this country.
- Full Text:
- Date Issued: 2004
The effect of diet type and feeding rate on growth, morphological development and behaviour of larval and juvenile goldfish Carassius auratus (L.)
- Authors: Paulet, Timothy Guy
- Date: 2004
- Subjects: Goldfish -- Growth , Goldfish -- Nutrition , Goldfish -- Development , Goldfish -- Larvae
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5271 , http://hdl.handle.net/10962/d1005115 , Goldfish -- Growth , Goldfish -- Nutrition , Goldfish -- Development , Goldfish -- Larvae
- Description: Intensive grow-out of goldfish, Carassius auratus (L.), larvae and juveniles in closed recirculating systems requires the control of environmental conditions and feeding. This study investigated the effect of different diets, environmental condition and feeding level on growth, development and survival of goldfish larvae and juveniles. Prey preference for Artemia nauplii or decapsulated Artemia cysts as well as agonistic behaviour was recorded. The micrometer device used to measure mouth-gape was shown to produce accurate measurements which could be used to estimate the maximal particle size that can be ingested by goldfish larvae of a particular age. Goldfish completed metamorphosis earlier with an increased feeding level of Artemia cysts and by making the cysts more accessible to the fish using up-welling water movement. Morphometric plasticity in goldfish larvae was exhibited within two weeks of growth and it may be possible to induce changes in morphology by manipulating diet and rearing environment. Fish that fed on moving prey items had a significantly larger mouth-gape than those that browsed cysts from the tank bottom or dry food items. The development of mouth-gape was not affected by the feeding level of cysts. Condition factor increased with an increase in the number of cysts fed per fish per day. Goldfish larvae and juveniles grew faster and had a higher survival when fed on decapsulated Artemia cysts than on instar I Artemia nauplii or a mixed live/dry diet of Artemia nauplii and dry food. Feeding at least 155 cysts per fish per day, in tanks with upwelling water movement, gave the best growth and survival and the smallest size variation. In addition, cysts remained available to the fish for longer periods, and were easier to prepare and feed. Goldfish larvae preferred decapsulated Artemia cysts to nauplii and rejected fewer prey items as they grew older. The frequency of agonistic behaviour increased as fish grew but no cannibalism was recorded for cyst-fed fish. This study showed that decapsulated Artemia cysts are a good alternative to Artemia nauplii as a diet for larval goldfish. Good growth and high survival was achieved for cyst-fed goldfish larvae and juveniles at 23 ± 1.5°C and at an initial stocking density of 12 fish per litre. This research also contributes to an understanding of feeding behaviour and attempts to minimise under- or over-feeding of Artemia cysts in order to reduce grow-out costs due to the high value of the feed type.
- Full Text:
- Date Issued: 2004
- Authors: Paulet, Timothy Guy
- Date: 2004
- Subjects: Goldfish -- Growth , Goldfish -- Nutrition , Goldfish -- Development , Goldfish -- Larvae
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5271 , http://hdl.handle.net/10962/d1005115 , Goldfish -- Growth , Goldfish -- Nutrition , Goldfish -- Development , Goldfish -- Larvae
- Description: Intensive grow-out of goldfish, Carassius auratus (L.), larvae and juveniles in closed recirculating systems requires the control of environmental conditions and feeding. This study investigated the effect of different diets, environmental condition and feeding level on growth, development and survival of goldfish larvae and juveniles. Prey preference for Artemia nauplii or decapsulated Artemia cysts as well as agonistic behaviour was recorded. The micrometer device used to measure mouth-gape was shown to produce accurate measurements which could be used to estimate the maximal particle size that can be ingested by goldfish larvae of a particular age. Goldfish completed metamorphosis earlier with an increased feeding level of Artemia cysts and by making the cysts more accessible to the fish using up-welling water movement. Morphometric plasticity in goldfish larvae was exhibited within two weeks of growth and it may be possible to induce changes in morphology by manipulating diet and rearing environment. Fish that fed on moving prey items had a significantly larger mouth-gape than those that browsed cysts from the tank bottom or dry food items. The development of mouth-gape was not affected by the feeding level of cysts. Condition factor increased with an increase in the number of cysts fed per fish per day. Goldfish larvae and juveniles grew faster and had a higher survival when fed on decapsulated Artemia cysts than on instar I Artemia nauplii or a mixed live/dry diet of Artemia nauplii and dry food. Feeding at least 155 cysts per fish per day, in tanks with upwelling water movement, gave the best growth and survival and the smallest size variation. In addition, cysts remained available to the fish for longer periods, and were easier to prepare and feed. Goldfish larvae preferred decapsulated Artemia cysts to nauplii and rejected fewer prey items as they grew older. The frequency of agonistic behaviour increased as fish grew but no cannibalism was recorded for cyst-fed fish. This study showed that decapsulated Artemia cysts are a good alternative to Artemia nauplii as a diet for larval goldfish. Good growth and high survival was achieved for cyst-fed goldfish larvae and juveniles at 23 ± 1.5°C and at an initial stocking density of 12 fish per litre. This research also contributes to an understanding of feeding behaviour and attempts to minimise under- or over-feeding of Artemia cysts in order to reduce grow-out costs due to the high value of the feed type.
- Full Text:
- Date Issued: 2004
The enzymology of enhanced hydrolysis within the biosulphidogenic recycling sludge bed reactor (RSBR)
- Authors: Enongene, Godlove Nkwelle
- Date: 2004
- Subjects: Hydrolysis , Sewage sludge , Sewage -- Purification -- Anaerobic treatment , Water -- Purification -- Biological treatment
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4132 , http://hdl.handle.net/10962/d1015744
- Description: The hydrolysis of complex organic heteropolymers contained in municipal wastewater to simpler monomers by extracellular hydrolytic enzymes is generally considered the rate-limiting step of the biodegradation process. Previous studies of the Recycling Sludge Bed Reactor (RSBR) revealed that the hydrolysis of complex particulate organics, such as those contained in primary sludge (PS), was enhanced under anaerobic biosulphidogenic conditions. Although the mechanism was not fully understood, it appeared to involve the interaction of sulfide and sludge flocs. The current study was conducted using a 3500 ml laboratory-scale RSBR fed sieved PS at a loading rate of 0.5 kg COD/m³.day and an initial chemical oxygen demand (COD) to sulfate ratio (COD:SO₄) of 1:1. There was no significant accumulation of undigested sludge in the reactor over the 60-day experimental period and the quantity of SO₄ reduced indicated that the yield of soluble products from PS was at least as high as those reported previously for this system (> 50%). In the current study, the specific activities of a range of extracellular hydrolytic enzymes (L-alanine aminopeptidase, L-leucine aminopeptidase, arylsulphatase, α-glucosidase, β- glucosidase, protease and lipase) were monitored in a sulfide gradient within a biosulphidogenic RSBR. Data obtained indicated that the specific enzymatic activities increased with the depth of the RSBR and also correlated with a number of the physicochemical parameters including sulfide, alkalinity and sulfate. The activities of α- glucosidase and β-glucosidase were higher than that of the other enzymes studied. Lipase activity was relatively low and studies conducted on the enzyme-enzyme interaction using specific enzyme inhibitors indicated that lipases were probably being digested by the proteases. Further studies to determine the impact of sulfide on the enzymes, showed an increase in the enzyme activity with increasing sulfide concentration. Possible direct affects were investigated by looking for changes in the Michaelis constant (Km) and the maximal velocity (Vmax) of the crude enzymes with varying sulfide concentrations (250, 400 and 500 mg/l) using natural and synthetic substrates. The results showed no significant difference in both the Km and the Vmax for any of the hydrolytic enzymes except for the protease. The latter showed a statistically significant increase in the Km with increasing sulfide concentration. Although this indicated a direct interaction, this difference was not large enough to be of biochemical significance and was consequently not solely responsible for the enhanced hydrolysis observed in the RSBR. Investigation into the floc characteristics indicated that the biosulphidogenic RSBR flocs were generally small in size and became more dendritic with the depth of the RSBR. Based on the above data, the previously proposed descriptive models of enhanced hydrolysis of particulate organic matter in a biosulphidogenic RSBR has been revised. It is thought that the effect of sulfide on the hydrolysis step is primarily indirect and that the reduction in floc size and alteration of the floc shape to a more dendritic form is central to the success of the process.
- Full Text:
- Date Issued: 2004
- Authors: Enongene, Godlove Nkwelle
- Date: 2004
- Subjects: Hydrolysis , Sewage sludge , Sewage -- Purification -- Anaerobic treatment , Water -- Purification -- Biological treatment
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4132 , http://hdl.handle.net/10962/d1015744
- Description: The hydrolysis of complex organic heteropolymers contained in municipal wastewater to simpler monomers by extracellular hydrolytic enzymes is generally considered the rate-limiting step of the biodegradation process. Previous studies of the Recycling Sludge Bed Reactor (RSBR) revealed that the hydrolysis of complex particulate organics, such as those contained in primary sludge (PS), was enhanced under anaerobic biosulphidogenic conditions. Although the mechanism was not fully understood, it appeared to involve the interaction of sulfide and sludge flocs. The current study was conducted using a 3500 ml laboratory-scale RSBR fed sieved PS at a loading rate of 0.5 kg COD/m³.day and an initial chemical oxygen demand (COD) to sulfate ratio (COD:SO₄) of 1:1. There was no significant accumulation of undigested sludge in the reactor over the 60-day experimental period and the quantity of SO₄ reduced indicated that the yield of soluble products from PS was at least as high as those reported previously for this system (> 50%). In the current study, the specific activities of a range of extracellular hydrolytic enzymes (L-alanine aminopeptidase, L-leucine aminopeptidase, arylsulphatase, α-glucosidase, β- glucosidase, protease and lipase) were monitored in a sulfide gradient within a biosulphidogenic RSBR. Data obtained indicated that the specific enzymatic activities increased with the depth of the RSBR and also correlated with a number of the physicochemical parameters including sulfide, alkalinity and sulfate. The activities of α- glucosidase and β-glucosidase were higher than that of the other enzymes studied. Lipase activity was relatively low and studies conducted on the enzyme-enzyme interaction using specific enzyme inhibitors indicated that lipases were probably being digested by the proteases. Further studies to determine the impact of sulfide on the enzymes, showed an increase in the enzyme activity with increasing sulfide concentration. Possible direct affects were investigated by looking for changes in the Michaelis constant (Km) and the maximal velocity (Vmax) of the crude enzymes with varying sulfide concentrations (250, 400 and 500 mg/l) using natural and synthetic substrates. The results showed no significant difference in both the Km and the Vmax for any of the hydrolytic enzymes except for the protease. The latter showed a statistically significant increase in the Km with increasing sulfide concentration. Although this indicated a direct interaction, this difference was not large enough to be of biochemical significance and was consequently not solely responsible for the enhanced hydrolysis observed in the RSBR. Investigation into the floc characteristics indicated that the biosulphidogenic RSBR flocs were generally small in size and became more dendritic with the depth of the RSBR. Based on the above data, the previously proposed descriptive models of enhanced hydrolysis of particulate organic matter in a biosulphidogenic RSBR has been revised. It is thought that the effect of sulfide on the hydrolysis step is primarily indirect and that the reduction in floc size and alteration of the floc shape to a more dendritic form is central to the success of the process.
- Full Text:
- Date Issued: 2004
The enzymology of sludge solubilisation under biosulphidogenic conditions : isolation, characterisation and partial purification of endoglucanases
- Authors: Oyekola, Oluwaseun Oyekanmi
- Date: 2004
- Subjects: Sewage -- Purification -- Anaerobic treatment , Anaerobic bacteria , Sewage sludge , Hydrolysis
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3921 , http://hdl.handle.net/10962/d1003980 , Sewage -- Purification -- Anaerobic treatment , Anaerobic bacteria , Sewage sludge , Hydrolysis
- Description: Endoglucanases play an important function in cellulose hydrolysis and catalyse the initial attack on the polymer by randomly hydrolysing the β-1,4 glucosidic bonds within the amorphous regions of cellulose chains. Cellulolytic bacteria have been isolated and characterised from the sewage sludge and the activation of several hydrolytic enzymes under biosulphidogenic conditions of sewage hydrolysis has been reported. The aims of this study were to: identify, induce production, locate and isolate, characterise (physicochemical and kinetic) and purify endoglucanases from anaerobic biosulphidogenic sludge. The endoglucanase activities were shown to be associated with the pellet particulate matter and exhibited a pH optimum of 6 and temperature optimum of 50 °C. The enzymes were thermally more stable when immobilised to the floc matrix of the sludge than when they were released into the aqueous solution via sonication. For both immobilised and released enzymes, sulphate was slightly inhibitory; activity was reduced to 84 % and 77.5 % of the initial activity at sulphate concentrations between 200 and 1000 mg/l, respectively. Sulphite was stimulatory to the immobilised enzymes between 200 and 1000 mg/l. Sulphide stimulated the activities of the immobilised endoglucanases, but inhibited activities of the soluble enzymes above 200 mg/l. The enzyme fraction did not hydrolyse avicel (a crystalline substrate), indicating the absence of any exocellulase activity. For CMC (carboxymethylcellulose) and HEC (hydroxylethylcellulose) the enzyme had K_m,app_ values of 4 and 5.1 mg/ml respectively and V_max,app_ values of 0.297 and 0.185 μmol/min/ml respectively. Divalent ions (Cu²⁺, Ni²⁺ and Zn²⁺) proved to be inhibitory while Fe²⁺, Mg²⁺ and Ca²⁺ stimulated the enzyme at concentrations between 200 and 1000 mg/l. All the volatile fatty acids studied (acetic acid, butyric acid, propionic acid and valeric acid) inhibited the enzymes, with acetic acid eliciting the highest degree of inhibition. Sonication released ~74.9 % of the total enzyme activities into solution and this was partially purified by PEG 20 000 concentration followed by DEAE-Cellulose ion exchange chromatography, which resulted in an appreciable purity as measured by the purification factor, 25.4 fold.
- Full Text:
- Date Issued: 2004
- Authors: Oyekola, Oluwaseun Oyekanmi
- Date: 2004
- Subjects: Sewage -- Purification -- Anaerobic treatment , Anaerobic bacteria , Sewage sludge , Hydrolysis
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3921 , http://hdl.handle.net/10962/d1003980 , Sewage -- Purification -- Anaerobic treatment , Anaerobic bacteria , Sewage sludge , Hydrolysis
- Description: Endoglucanases play an important function in cellulose hydrolysis and catalyse the initial attack on the polymer by randomly hydrolysing the β-1,4 glucosidic bonds within the amorphous regions of cellulose chains. Cellulolytic bacteria have been isolated and characterised from the sewage sludge and the activation of several hydrolytic enzymes under biosulphidogenic conditions of sewage hydrolysis has been reported. The aims of this study were to: identify, induce production, locate and isolate, characterise (physicochemical and kinetic) and purify endoglucanases from anaerobic biosulphidogenic sludge. The endoglucanase activities were shown to be associated with the pellet particulate matter and exhibited a pH optimum of 6 and temperature optimum of 50 °C. The enzymes were thermally more stable when immobilised to the floc matrix of the sludge than when they were released into the aqueous solution via sonication. For both immobilised and released enzymes, sulphate was slightly inhibitory; activity was reduced to 84 % and 77.5 % of the initial activity at sulphate concentrations between 200 and 1000 mg/l, respectively. Sulphite was stimulatory to the immobilised enzymes between 200 and 1000 mg/l. Sulphide stimulated the activities of the immobilised endoglucanases, but inhibited activities of the soluble enzymes above 200 mg/l. The enzyme fraction did not hydrolyse avicel (a crystalline substrate), indicating the absence of any exocellulase activity. For CMC (carboxymethylcellulose) and HEC (hydroxylethylcellulose) the enzyme had K_m,app_ values of 4 and 5.1 mg/ml respectively and V_max,app_ values of 0.297 and 0.185 μmol/min/ml respectively. Divalent ions (Cu²⁺, Ni²⁺ and Zn²⁺) proved to be inhibitory while Fe²⁺, Mg²⁺ and Ca²⁺ stimulated the enzyme at concentrations between 200 and 1000 mg/l. All the volatile fatty acids studied (acetic acid, butyric acid, propionic acid and valeric acid) inhibited the enzymes, with acetic acid eliciting the highest degree of inhibition. Sonication released ~74.9 % of the total enzyme activities into solution and this was partially purified by PEG 20 000 concentration followed by DEAE-Cellulose ion exchange chromatography, which resulted in an appreciable purity as measured by the purification factor, 25.4 fold.
- Full Text:
- Date Issued: 2004
The experiences and needs of HIV/AIDS counsellors at Settlers Hospital, Grahamstown
- Authors: Nulty, Maria
- Date: 2004
- Subjects: AIDS (Disease) -- Patients -- Counseling of -- South Africa -- Eastern Cape HIV-positive persons -- Counseling of -- South Africa -- Eastern Cape Counselors -- South Africa -- Eastern Cape Counselors -- Supervision of -- South Africa -- Eastern Cape Counselors -- Training of -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3032 , http://hdl.handle.net/10962/d1002541
- Description: Cognisant of the fact that counselling has become an essential aspect of dealing with HIV/AIDS in South Africa, the researcher aimed to explore the stressors experienced by HIV/AIDS counsellors. It was envisioned that the results obtained would both help to improve the counselling services provided at Settlers Hospital, and assist other organisations to do so. The research focused on how the participants dealt with the dual roles of non-directive listening and the more prescriptive advice-giving, the stressors they experienced and the support structures they had, or needed, to assist them in being more effective HIV/AIDS counsellors. The sample consisted of four HIV/AIDS counsellors working at Settlers Hospital, Grahamstown. The co-ordinator of HIV/AIDS at the hospital was interviewed for collateral information. A qualitative, multiple case study was undertaken. In-depth, semi-structured interviews were used to collect the data which were recorded and transcribed and then constructed into coherently organised personal narratives of each participant’s experiences. A composite description of all the results was arrived at through the use of a reading guide which reduced the data into a thematic content analysis. The analysed data served to present an understanding of the counsellors’ experiences and to enable recommendations to be made which could assist them in pursuing their work more effectively. The findings of this study indicate that HIV/AIDS counselling is an emotionally stressful occupation. Contributory factors include the twofold role of promoting prevention and serving as empathic listeners. Other stressors derive from issues of confidentiality and stigma concerning HIV/AIDS, counsellors’ identification with clients’ experiences and the demographics of HIV/AIDS in South Africa. Situational stressors which arise from working as both nurses and counsellors in a public health institution were also identified. Recommendations are made to alleviate the counsellors’ stress in the form of facilitated emotional support groups, professional supervision, managerial support to improve the working environment, and ongoing in-service training.
- Full Text:
- Date Issued: 2004
- Authors: Nulty, Maria
- Date: 2004
- Subjects: AIDS (Disease) -- Patients -- Counseling of -- South Africa -- Eastern Cape HIV-positive persons -- Counseling of -- South Africa -- Eastern Cape Counselors -- South Africa -- Eastern Cape Counselors -- Supervision of -- South Africa -- Eastern Cape Counselors -- Training of -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3032 , http://hdl.handle.net/10962/d1002541
- Description: Cognisant of the fact that counselling has become an essential aspect of dealing with HIV/AIDS in South Africa, the researcher aimed to explore the stressors experienced by HIV/AIDS counsellors. It was envisioned that the results obtained would both help to improve the counselling services provided at Settlers Hospital, and assist other organisations to do so. The research focused on how the participants dealt with the dual roles of non-directive listening and the more prescriptive advice-giving, the stressors they experienced and the support structures they had, or needed, to assist them in being more effective HIV/AIDS counsellors. The sample consisted of four HIV/AIDS counsellors working at Settlers Hospital, Grahamstown. The co-ordinator of HIV/AIDS at the hospital was interviewed for collateral information. A qualitative, multiple case study was undertaken. In-depth, semi-structured interviews were used to collect the data which were recorded and transcribed and then constructed into coherently organised personal narratives of each participant’s experiences. A composite description of all the results was arrived at through the use of a reading guide which reduced the data into a thematic content analysis. The analysed data served to present an understanding of the counsellors’ experiences and to enable recommendations to be made which could assist them in pursuing their work more effectively. The findings of this study indicate that HIV/AIDS counselling is an emotionally stressful occupation. Contributory factors include the twofold role of promoting prevention and serving as empathic listeners. Other stressors derive from issues of confidentiality and stigma concerning HIV/AIDS, counsellors’ identification with clients’ experiences and the demographics of HIV/AIDS in South Africa. Situational stressors which arise from working as both nurses and counsellors in a public health institution were also identified. Recommendations are made to alleviate the counsellors’ stress in the form of facilitated emotional support groups, professional supervision, managerial support to improve the working environment, and ongoing in-service training.
- Full Text:
- Date Issued: 2004
The feeding biology and potential impact of introduced giraffe (Giraffa camelopardalis) in the Eastern Cape Province, South Africa
- Authors: Parker, Daniel Matthew
- Date: 2004
- Subjects: Giraffe -- South Africa -- Eastern Cape , Animal-plant relationships -- South Africa -- Eastern Cape , Giraffe -- Food -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5694 , http://hdl.handle.net/10962/d1005380
- Description: Giraffe (Giraffa camelopardalis) are extralimital (non-native) to the Eastern Cape Province, South Africa yet they have and continue to be introduced to the region. Financial gain has arguably been the driving force behind these introductions as foreign tourists associate giraffe with Africa and the African wildlife experience. This raises a number of ethical, ecological and philosophical questions especially when it is considered that the impact of these browsers on the indigenous vegetation has remained largely unquantified. In this study I assessed the diet and potential impact of three populations of giraffe in the Eastern Cape Province between January 2002 and October 2003. The diet was assessed by both direct observations and faecal analysis. There was no significant difference (P > 0.05) between the results of the two methods of analysis, although direct observations appeared to be a superior method for assessing the diet of giraffe. The diet of giraffe in the Eastern Cape Province was similar to that within their native range with a deciduous species from the genus Acacia (Acacia karroo) being the most important component of the diet. However, giraffe in the Eastern Cape Province consumed more evergreen plant species than those within their native range. The relative lack of deciduous species in the Eastern Cape Province provides a likely explanation for such a result. Seasonal variation in the consumption of the most important species in the diet was evident and this was attributed to the deciduous nature of A. karroo and the seasonal growth of new shoots which were more palatable. The vegetation of the areas most commonly utilised by giraffe at each site was sampled using the point-centred-quarter method and the results related to the frequency of each species in the diet to calculate preference indices. Giraffe preference was strongest for A. karroo and this was attributed to the highly favourable chemical composition of the species. The browse utilisation of giraffe at each site was determined using the twig-length method and intake rates for the three most important species in the diet calculated using a pre-existing regression equation. Male giraffe fed at a higher rate than females. This was probably due to males adopting a “time-minimising” strategy to their feeding in order to allow more time for reproductive pursuits. Giraffe browse utilisation was highest where giraffe density was highest. However, several species were more heavily browsed than others even when giraffe density was low, suggesting that giraffe are capable of negatively affecting the indigenous flora of the province. I conclude that giraffe numbers should be reduced relative to property size in the Eastern Cape Province and that research into the impact of not only giraffe but the combined effects of giraffe and other extralimital herbivores on the indigenous flora and fauna be continued.
- Full Text:
- Date Issued: 2004
- Authors: Parker, Daniel Matthew
- Date: 2004
- Subjects: Giraffe -- South Africa -- Eastern Cape , Animal-plant relationships -- South Africa -- Eastern Cape , Giraffe -- Food -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5694 , http://hdl.handle.net/10962/d1005380
- Description: Giraffe (Giraffa camelopardalis) are extralimital (non-native) to the Eastern Cape Province, South Africa yet they have and continue to be introduced to the region. Financial gain has arguably been the driving force behind these introductions as foreign tourists associate giraffe with Africa and the African wildlife experience. This raises a number of ethical, ecological and philosophical questions especially when it is considered that the impact of these browsers on the indigenous vegetation has remained largely unquantified. In this study I assessed the diet and potential impact of three populations of giraffe in the Eastern Cape Province between January 2002 and October 2003. The diet was assessed by both direct observations and faecal analysis. There was no significant difference (P > 0.05) between the results of the two methods of analysis, although direct observations appeared to be a superior method for assessing the diet of giraffe. The diet of giraffe in the Eastern Cape Province was similar to that within their native range with a deciduous species from the genus Acacia (Acacia karroo) being the most important component of the diet. However, giraffe in the Eastern Cape Province consumed more evergreen plant species than those within their native range. The relative lack of deciduous species in the Eastern Cape Province provides a likely explanation for such a result. Seasonal variation in the consumption of the most important species in the diet was evident and this was attributed to the deciduous nature of A. karroo and the seasonal growth of new shoots which were more palatable. The vegetation of the areas most commonly utilised by giraffe at each site was sampled using the point-centred-quarter method and the results related to the frequency of each species in the diet to calculate preference indices. Giraffe preference was strongest for A. karroo and this was attributed to the highly favourable chemical composition of the species. The browse utilisation of giraffe at each site was determined using the twig-length method and intake rates for the three most important species in the diet calculated using a pre-existing regression equation. Male giraffe fed at a higher rate than females. This was probably due to males adopting a “time-minimising” strategy to their feeding in order to allow more time for reproductive pursuits. Giraffe browse utilisation was highest where giraffe density was highest. However, several species were more heavily browsed than others even when giraffe density was low, suggesting that giraffe are capable of negatively affecting the indigenous flora of the province. I conclude that giraffe numbers should be reduced relative to property size in the Eastern Cape Province and that research into the impact of not only giraffe but the combined effects of giraffe and other extralimital herbivores on the indigenous flora and fauna be continued.
- Full Text:
- Date Issued: 2004
The geology of the Proterozoic Haveri Au-Cu deposit, Southern Finland
- Strauss, Toby Anthony Lavery
- Authors: Strauss, Toby Anthony Lavery
- Date: 2004
- Subjects: Geology, Stratigraphic -- Precambrian , Geology, Stratigraphic -- Proterozoic , Ore deposits -- Finland , Geology -- Finland
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5081 , http://hdl.handle.net/10962/d1015978
- Description: The Haveri Au-Cu deposit is located in southern Finland about 175 km north of Helsinki. It occurs on the northern edge of the continental island arc-type, volcano-sedimentary Tampere Schist Belt (TSB) within the Palaeoproterozoic Svecofennian Domain (2.0 – 1.75 Ga) of the Fennoscandian Shield. The 1.99 Ga Haveri Formation forms the base of the supracrustal stratigraphy consisting of metavolcanic pillow lavas and breccias passing upwards into intercalated metatuffs and metatuffites. There is a continuous gradation upwards from the predominantly volcaniclastic Haveri Formation into the overlying epiclastic meta-greywackes of the Osara Formation. The Haveri deposit is hosted in this contact zone. This supracrustal sequence has been intruded concordantly by quartz-feldspar porphyries. Approximately 1.89 Ga ago, high crustal heat flow led to the generation and emplacement of voluminous synkinematic, I-type, magnetite-series granitoids of the Central Finland Granitoid Complex (CFGC), resulting in coeval high-T/low-P metamorphism (hornfelsic textures), and D₁ deformation. During the crystallisation and cooling of the granitoids, a magmatic-dominated hydrothermal system caused extensive hydrothermal alteration and Cu-Au mineralisation through the late-D₁ to early-D₂ deformation. Initially, a pre-ore Na-Ca alteration phase caused albitisation of the host rock. This was closely followed by strong Ca-Fe alteration, responsible for widespread amphibolitisation and quartz veining and associated with abundant pyrrhotite, magnetite, chalcopyrite and gold mineralisation. More localised calcic-skarn alteration is also present as zoned garnetpyroxene- epidote skarn assemblages with associated pyrrhotite and minor sphalerite, centred on quartzcalcite± scapolite veinlets. Post-ore alteration includes an evolution to more K-rich alteration (biotitisation). Late D₂-retrograde chlorite began to replace the earlier high-T assemblage. Late emanations (post-D₂ and pre-D₃) from the cooling granitoids, under lower temperatures and oxidising conditions, are represented by carbonate-barite veins and epidote veinlets. Later, narrow dolerite dykes were emplaced followed by a weak D₃ deformation, resulting in shearing and structural reactivation along the carbonate-barite bands. This phase was accompanied by pyrite deposition. Both sulphides and oxides are common at Haveri, with ore types varying from massive sulphide and/or magnetite, to networks of veinlets and disseminations of oxides and/or sulphides. Cataclastites, consisting of deformed, brecciated bands of sulphide, with rounded and angular clasts of quartz vein material and altered host-rock are an economically important ore type. Ore minerals are principally pyrrhotite, magnetite and chalcopyrite with lesser amounts of pyrite, molybdenite and sphalerite. There is a general progression from early magnetite, through pyrrhotite to pyrite indicating increasing sulphidation with time. Gold is typically found as free gold within quartz veins and within intense zones of amphibolitisation. Considerable gold is also found in the cataclastite ore type either as invisible gold within the sulphides and/or as free gold within the breccia fragments. The unaltered amphibolites of the Haveri Formation can be classified as medium-K basalts of the tholeiitic trend. Trace and REE support an interpretation of formation in a back-arc basin setting. The unaltered porphyritic rocks are calc-alkaline dacites, and are interpreted, along with the granitoids as having an arc-type origin. This is consistent with the evolution from an initial back-arc basin, through a period of passive margin and/or fore-arc deposition represented by the Osara Formation greywackes and the basal stratigraphy of the TSB, prior to the onset of arc-related volcanic activity characteristic of the TSB and the Svecofennian proper. Using a combination of petrogenetic grids, mineral compositions (garnet-biotite and hornblendeplagioclase thermometers) and oxygen isotope thermometry, peak metamorphism can be constrained to a maximum of approximately 600 °C and 1.5 kbars pressure. Furthermore, the petrogenetic grids indicate that the REDOX conditions can be constrained at 600°C to log f(O₂) values of approximately - 21.0 to -26.0 and -14.5 to -17.5 for the metasedimentary rocks and mafic metavolcanic rocks respectively, thus indicating the presence of a significant REDOX boundary. Amphibole compositions from the Ca-Fe alteration phase (amphibolitisation) indicate iron enrichment with increasing alteration corresponding to higher temperatures of formation. Oxygen isotope studies combined with limited fluid inclusion studies indicate that the Ca-Fe alteration and associated quartz veins formed at high temperatures (530 – 610°C) from low CO₂, low- to moderately saline (<10 eq. wt% NaCl), magmatic-dominated fluids. Fluid inclusion decrepitation textures in the quartz veins suggest isobaric decompression. This is compatible with formation in high-T/low-P environments such as contact aureoles and island arcs. The calcic-skarn assemblage, combined with phase equilibria and sphalerite geothermometry, are indicative of formation at high temperatures (500 – 600 °C) from fluids with higher CO₂ contents and more saline compositions than those responsible for the Fe-Ca alteration. Limited fluid inclusion studies have identified hypersaline inclusions in secondary inclusion trails within quartz. The presence of calcite and scapolite also support formation from CO₂-rich saline fluids. It is suggested that the calcic-skarn alteration and the amphibolitisation evolved from the same fluids, and that P-T changes led to fluid unmixing resulting in two fluid types responsible for the observed alteration variations. Chlorite geothermometry on retrograde chlorite indicates temperatures of 309 – 368 °C. As chlorite represents the latest hydrothermal event, this can be taken as a lower temperature limit for hydrothermal alteration and mineralisation at Haveri.The gold mineralisation at Haveri is related primarily to the Ca-Fe alteration. Under such P-T-X conditions gold was transported as chloride complexes. Ore was localised by a combination of structural controls (shears and folds) and REDOX reactions along the boundary between the oxidised metavolcanics and the reduced metasediments. In addition, fluid unmixing caused an increase in pH, and thus further augmented the precipitation of Cu and Au. During the late D₂-event, temperatures fell below 400 °C, and fluids may have remobilised Au and Cu as bisulphide complexes into the shearcontrolled cataclastites and massive sulphides. The Haveri deposit has many similarities with ore deposit models that include orogenic lode-gold deposits, certain Au-skarn deposits and Fe-oxide Cu-Au deposits. However, many characteristics of the Haveri deposit, including tectonic setting, host lithologies, alteration types, proximity to I-type granitoids and P-T-X conditions of formation, compare favourably with other Early Proterozoic deposits within the TSB and Fennoscandia, as well as many of the deposits in the Cloncurry district of Australia. Consequently, the Haveri deposit can be seen to represent a high-T, Ca-rich member of the recently recognised Fe-oxide Cu-Au group of deposits.
- Full Text:
- Date Issued: 2004
- Authors: Strauss, Toby Anthony Lavery
- Date: 2004
- Subjects: Geology, Stratigraphic -- Precambrian , Geology, Stratigraphic -- Proterozoic , Ore deposits -- Finland , Geology -- Finland
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5081 , http://hdl.handle.net/10962/d1015978
- Description: The Haveri Au-Cu deposit is located in southern Finland about 175 km north of Helsinki. It occurs on the northern edge of the continental island arc-type, volcano-sedimentary Tampere Schist Belt (TSB) within the Palaeoproterozoic Svecofennian Domain (2.0 – 1.75 Ga) of the Fennoscandian Shield. The 1.99 Ga Haveri Formation forms the base of the supracrustal stratigraphy consisting of metavolcanic pillow lavas and breccias passing upwards into intercalated metatuffs and metatuffites. There is a continuous gradation upwards from the predominantly volcaniclastic Haveri Formation into the overlying epiclastic meta-greywackes of the Osara Formation. The Haveri deposit is hosted in this contact zone. This supracrustal sequence has been intruded concordantly by quartz-feldspar porphyries. Approximately 1.89 Ga ago, high crustal heat flow led to the generation and emplacement of voluminous synkinematic, I-type, magnetite-series granitoids of the Central Finland Granitoid Complex (CFGC), resulting in coeval high-T/low-P metamorphism (hornfelsic textures), and D₁ deformation. During the crystallisation and cooling of the granitoids, a magmatic-dominated hydrothermal system caused extensive hydrothermal alteration and Cu-Au mineralisation through the late-D₁ to early-D₂ deformation. Initially, a pre-ore Na-Ca alteration phase caused albitisation of the host rock. This was closely followed by strong Ca-Fe alteration, responsible for widespread amphibolitisation and quartz veining and associated with abundant pyrrhotite, magnetite, chalcopyrite and gold mineralisation. More localised calcic-skarn alteration is also present as zoned garnetpyroxene- epidote skarn assemblages with associated pyrrhotite and minor sphalerite, centred on quartzcalcite± scapolite veinlets. Post-ore alteration includes an evolution to more K-rich alteration (biotitisation). Late D₂-retrograde chlorite began to replace the earlier high-T assemblage. Late emanations (post-D₂ and pre-D₃) from the cooling granitoids, under lower temperatures and oxidising conditions, are represented by carbonate-barite veins and epidote veinlets. Later, narrow dolerite dykes were emplaced followed by a weak D₃ deformation, resulting in shearing and structural reactivation along the carbonate-barite bands. This phase was accompanied by pyrite deposition. Both sulphides and oxides are common at Haveri, with ore types varying from massive sulphide and/or magnetite, to networks of veinlets and disseminations of oxides and/or sulphides. Cataclastites, consisting of deformed, brecciated bands of sulphide, with rounded and angular clasts of quartz vein material and altered host-rock are an economically important ore type. Ore minerals are principally pyrrhotite, magnetite and chalcopyrite with lesser amounts of pyrite, molybdenite and sphalerite. There is a general progression from early magnetite, through pyrrhotite to pyrite indicating increasing sulphidation with time. Gold is typically found as free gold within quartz veins and within intense zones of amphibolitisation. Considerable gold is also found in the cataclastite ore type either as invisible gold within the sulphides and/or as free gold within the breccia fragments. The unaltered amphibolites of the Haveri Formation can be classified as medium-K basalts of the tholeiitic trend. Trace and REE support an interpretation of formation in a back-arc basin setting. The unaltered porphyritic rocks are calc-alkaline dacites, and are interpreted, along with the granitoids as having an arc-type origin. This is consistent with the evolution from an initial back-arc basin, through a period of passive margin and/or fore-arc deposition represented by the Osara Formation greywackes and the basal stratigraphy of the TSB, prior to the onset of arc-related volcanic activity characteristic of the TSB and the Svecofennian proper. Using a combination of petrogenetic grids, mineral compositions (garnet-biotite and hornblendeplagioclase thermometers) and oxygen isotope thermometry, peak metamorphism can be constrained to a maximum of approximately 600 °C and 1.5 kbars pressure. Furthermore, the petrogenetic grids indicate that the REDOX conditions can be constrained at 600°C to log f(O₂) values of approximately - 21.0 to -26.0 and -14.5 to -17.5 for the metasedimentary rocks and mafic metavolcanic rocks respectively, thus indicating the presence of a significant REDOX boundary. Amphibole compositions from the Ca-Fe alteration phase (amphibolitisation) indicate iron enrichment with increasing alteration corresponding to higher temperatures of formation. Oxygen isotope studies combined with limited fluid inclusion studies indicate that the Ca-Fe alteration and associated quartz veins formed at high temperatures (530 – 610°C) from low CO₂, low- to moderately saline (<10 eq. wt% NaCl), magmatic-dominated fluids. Fluid inclusion decrepitation textures in the quartz veins suggest isobaric decompression. This is compatible with formation in high-T/low-P environments such as contact aureoles and island arcs. The calcic-skarn assemblage, combined with phase equilibria and sphalerite geothermometry, are indicative of formation at high temperatures (500 – 600 °C) from fluids with higher CO₂ contents and more saline compositions than those responsible for the Fe-Ca alteration. Limited fluid inclusion studies have identified hypersaline inclusions in secondary inclusion trails within quartz. The presence of calcite and scapolite also support formation from CO₂-rich saline fluids. It is suggested that the calcic-skarn alteration and the amphibolitisation evolved from the same fluids, and that P-T changes led to fluid unmixing resulting in two fluid types responsible for the observed alteration variations. Chlorite geothermometry on retrograde chlorite indicates temperatures of 309 – 368 °C. As chlorite represents the latest hydrothermal event, this can be taken as a lower temperature limit for hydrothermal alteration and mineralisation at Haveri.The gold mineralisation at Haveri is related primarily to the Ca-Fe alteration. Under such P-T-X conditions gold was transported as chloride complexes. Ore was localised by a combination of structural controls (shears and folds) and REDOX reactions along the boundary between the oxidised metavolcanics and the reduced metasediments. In addition, fluid unmixing caused an increase in pH, and thus further augmented the precipitation of Cu and Au. During the late D₂-event, temperatures fell below 400 °C, and fluids may have remobilised Au and Cu as bisulphide complexes into the shearcontrolled cataclastites and massive sulphides. The Haveri deposit has many similarities with ore deposit models that include orogenic lode-gold deposits, certain Au-skarn deposits and Fe-oxide Cu-Au deposits. However, many characteristics of the Haveri deposit, including tectonic setting, host lithologies, alteration types, proximity to I-type granitoids and P-T-X conditions of formation, compare favourably with other Early Proterozoic deposits within the TSB and Fennoscandia, as well as many of the deposits in the Cloncurry district of Australia. Consequently, the Haveri deposit can be seen to represent a high-T, Ca-rich member of the recently recognised Fe-oxide Cu-Au group of deposits.
- Full Text:
- Date Issued: 2004
The Harry Potter phenomenon literary production, generic traditions, and the question of values
- Authors: Glover, Jayne Ashleigh
- Date: 2004
- Subjects: Rowling, J. K. Criticism and interpretation , Potter, Harry (Fictitious character) , Children's literature -- History and criticism , Fantasy fiction, English -- History and criticism , Wizards in literature
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2201 , http://hdl.handle.net/10962/d1002243 , Rowling, J. K. Criticism and interpretation , Potter, Harry (Fictitious character) , Children's literature -- History and criticism , Fantasy fiction, English -- History and criticism , Wizards in literature
- Description: This thesis is a study of the first four books of J. K. Rowling’s Harry Potter series. It accounts for the widespread success of the novels by examining their publication and marketing histories, and their literary achievement as narratives including a sophisticated mix of generic traditions. Chapter One looks at the popularity of the novels, comparing their material production and marketing by Rowling’s English language publishers: Bloomsbury in Britain and Scholastic in the United States of America. The publisher’s influence on the public perception of each book is demonstrated by comparative study of its mode of illustration and layout. Further, the design of the books is linked to their strategic marketing and branding within the literary world. The second chapter considers Rowling’s debt to the school story. It concentrates first on the history of this relatively short-lived genre, briefly discussing its stereotypical features and values. Traditional elements of setting and characterisation are then examined to show how the Harry Potter novels present a value system which, though apparently old-fashioned, still has an ethical standpoint designed to appeal to the modern reader. Chapter Three focuses on the characterisation of Harry as a hero-figure, especially on how the influence of classical and medieval texts infuses Rowling’s portrayal of Harry as a hero in the chivalric mode. The episodes of “quest” and “test” in each book illustrate specifically how he learns the values of selflessness, loyalty, mercy and fairness. Chapter Four surveys the contribution of modern fantasy writing to the series. It shows how Rowling creates a secondary world that allows us to perceive magic as a metaphorical representation of power. This focus on the relationship between magic and power in turn has a bearing on our assessment of the author’s moral stance. The thesis concludes by suggesting that Rowling’s unusual mix of genres is justified by the values they share, and which are inscribed in her work: the generic combination forms a workable, new and exciting mode of writing that helps to account for the phenomenal popularity of the series.
- Full Text:
- Date Issued: 2004
- Authors: Glover, Jayne Ashleigh
- Date: 2004
- Subjects: Rowling, J. K. Criticism and interpretation , Potter, Harry (Fictitious character) , Children's literature -- History and criticism , Fantasy fiction, English -- History and criticism , Wizards in literature
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2201 , http://hdl.handle.net/10962/d1002243 , Rowling, J. K. Criticism and interpretation , Potter, Harry (Fictitious character) , Children's literature -- History and criticism , Fantasy fiction, English -- History and criticism , Wizards in literature
- Description: This thesis is a study of the first four books of J. K. Rowling’s Harry Potter series. It accounts for the widespread success of the novels by examining their publication and marketing histories, and their literary achievement as narratives including a sophisticated mix of generic traditions. Chapter One looks at the popularity of the novels, comparing their material production and marketing by Rowling’s English language publishers: Bloomsbury in Britain and Scholastic in the United States of America. The publisher’s influence on the public perception of each book is demonstrated by comparative study of its mode of illustration and layout. Further, the design of the books is linked to their strategic marketing and branding within the literary world. The second chapter considers Rowling’s debt to the school story. It concentrates first on the history of this relatively short-lived genre, briefly discussing its stereotypical features and values. Traditional elements of setting and characterisation are then examined to show how the Harry Potter novels present a value system which, though apparently old-fashioned, still has an ethical standpoint designed to appeal to the modern reader. Chapter Three focuses on the characterisation of Harry as a hero-figure, especially on how the influence of classical and medieval texts infuses Rowling’s portrayal of Harry as a hero in the chivalric mode. The episodes of “quest” and “test” in each book illustrate specifically how he learns the values of selflessness, loyalty, mercy and fairness. Chapter Four surveys the contribution of modern fantasy writing to the series. It shows how Rowling creates a secondary world that allows us to perceive magic as a metaphorical representation of power. This focus on the relationship between magic and power in turn has a bearing on our assessment of the author’s moral stance. The thesis concludes by suggesting that Rowling’s unusual mix of genres is justified by the values they share, and which are inscribed in her work: the generic combination forms a workable, new and exciting mode of writing that helps to account for the phenomenal popularity of the series.
- Full Text:
- Date Issued: 2004
The impact of smart cards on South African rural pensioners' lives
- Authors: Nyoka, Zanele
- Date: 2004
- Subjects: Old age pensioners -- South Africa -- Management Smart cards South African Post Office
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:818 , http://hdl.handle.net/10962/d1008052
- Description: E-commerce technologies have many possible applications both in commercial and non-commercial operations. The development and implementation of these applications is on the increase especially by government and its agencies, for the delivery of services. Specific to this study is the distribution of old age pension benefits to recipients that reside in the rural areas of South Africa. Of importance to this study are the factors that promote and impinge on the development, implementation and acceptance of these applications. A specific project, the Pension Biometric Project was implemented by the South African Post Office in line with the government's initiatives of improving service delivery, and in response to the encroaching digital economy. The research problem is to investigate the pensioners' perception and their experience of three areas of this project, its implementation, its acceptance and its uses and impact. The research was conducted in the constructivist paradigm, using the case study research method. Three data collection methods were used, i.e. a document study of SAPO project documentation, on-site observations and interviews with pensioners. It was found that despite problems in implementation, the pensioners were accepting of the new system, although they were ignorant of the functionalities of the smart card. Consequently, few pensioners were making use of the banking facilities of the card, or had changed their economic behaviour. The study has also found that two themes are overriding all findings of the study. These two themes are ignorance and dignity. Ignorance has had a causal effect on adoption of the smart cards and dignity has been found to be a result of the project. The overriding implication of this study is that pensioners' ignorance around issues of service delivery by government and its agencies needs to be eradicated, otherwise there is no reliable way of measuring efforts against actual delivery. Also, the fact that dignity has emerged as an overriding theme needs to be deliberately strengthened, and maybe even driven as a specified objective of the Pension Biometric Project. Recommendations in this regard are provided as well as ideas for further research.
- Full Text:
- Date Issued: 2004
- Authors: Nyoka, Zanele
- Date: 2004
- Subjects: Old age pensioners -- South Africa -- Management Smart cards South African Post Office
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:818 , http://hdl.handle.net/10962/d1008052
- Description: E-commerce technologies have many possible applications both in commercial and non-commercial operations. The development and implementation of these applications is on the increase especially by government and its agencies, for the delivery of services. Specific to this study is the distribution of old age pension benefits to recipients that reside in the rural areas of South Africa. Of importance to this study are the factors that promote and impinge on the development, implementation and acceptance of these applications. A specific project, the Pension Biometric Project was implemented by the South African Post Office in line with the government's initiatives of improving service delivery, and in response to the encroaching digital economy. The research problem is to investigate the pensioners' perception and their experience of three areas of this project, its implementation, its acceptance and its uses and impact. The research was conducted in the constructivist paradigm, using the case study research method. Three data collection methods were used, i.e. a document study of SAPO project documentation, on-site observations and interviews with pensioners. It was found that despite problems in implementation, the pensioners were accepting of the new system, although they were ignorant of the functionalities of the smart card. Consequently, few pensioners were making use of the banking facilities of the card, or had changed their economic behaviour. The study has also found that two themes are overriding all findings of the study. These two themes are ignorance and dignity. Ignorance has had a causal effect on adoption of the smart cards and dignity has been found to be a result of the project. The overriding implication of this study is that pensioners' ignorance around issues of service delivery by government and its agencies needs to be eradicated, otherwise there is no reliable way of measuring efforts against actual delivery. Also, the fact that dignity has emerged as an overriding theme needs to be deliberately strengthened, and maybe even driven as a specified objective of the Pension Biometric Project. Recommendations in this regard are provided as well as ideas for further research.
- Full Text:
- Date Issued: 2004
The implementation of multigrade teaching in rural schools in the Keetmanshoop education region: leadership and management challenges
- Authors: Titus, David Petrus
- Date: 2004
- Subjects: Education -- Namibia Education, Rural -- Namibia Education and state -- Namibia Educational change -- Namibia School management and organization -- Namibia Rural schools -- Namibia Educational leadership -- Namibia School principals -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1566 , http://hdl.handle.net/10962/d1003448
- Description: Leadership has received much attention in both the business world and education. My thesis explores effective educational leadership through examining the management and leadership challenges that face principals in a multi-grade school. Schools in sparsely populated rural areas in Namibia have had to resort to multi-grade teaching to be able to be economically viable. Hard economic realities force people to move to bigger towns and cities. The constant demand for better schools, effective principals, qualified teachers and an improved service to the communities coupled with the demand for better working conditions and salaries for teachers drained the education budget even further. To keep in line with the four major policies of education namely equity, access, quality and democracy, the operation of smaller, rural multi-grade schools has become a necessity. The alternative – which is to close smaller schools and operate fewer, bigger schools at an affordable and reasonable cost - would deny rural communities access to schooling. This thesis is a case study of the leadership and management challenges of multigrade schooling in a single school. The goal was to understand how education managers and leaders perceived their role in making it possible for teachers and learners to cope with multi-grade teaching. I worked in the interpretive paradigm to be able to interpret the social and cultural context of a rural, multi-grade school in the Karas region. The methods included questionnaires, interviews and observation. One of the leadership models universally considered to be available to principals of multi-grade schools is instructional leadership. My study revealed that the concept was unknown to teaching staff, although there were indications that the model had been encountered. My findings also revealed that the communication between colleges of education and the regional education department staff was very limited. One of the major issues that arose was that principals were so occupied with teaching that important issues about training/evaluation and supervision of teachers, the ‘visibility’ of the principal, setting and implementation of the aims and goals of the school and regular communication with parents and community leaders were neglected. Probably the most significant finding was that head teachers are not trained in the management of a multi-grade school, hence most if not all of the head teachers run multi-grade schools like a single-graded school. The single most important problem was that the importance of multi-grade teaching had never been highlighted, particularly in light of new staffing norms, in spite of the fact that it was a phenomenon that was likely to be a permanent arrangement.
- Full Text:
- Date Issued: 2004
- Authors: Titus, David Petrus
- Date: 2004
- Subjects: Education -- Namibia Education, Rural -- Namibia Education and state -- Namibia Educational change -- Namibia School management and organization -- Namibia Rural schools -- Namibia Educational leadership -- Namibia School principals -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1566 , http://hdl.handle.net/10962/d1003448
- Description: Leadership has received much attention in both the business world and education. My thesis explores effective educational leadership through examining the management and leadership challenges that face principals in a multi-grade school. Schools in sparsely populated rural areas in Namibia have had to resort to multi-grade teaching to be able to be economically viable. Hard economic realities force people to move to bigger towns and cities. The constant demand for better schools, effective principals, qualified teachers and an improved service to the communities coupled with the demand for better working conditions and salaries for teachers drained the education budget even further. To keep in line with the four major policies of education namely equity, access, quality and democracy, the operation of smaller, rural multi-grade schools has become a necessity. The alternative – which is to close smaller schools and operate fewer, bigger schools at an affordable and reasonable cost - would deny rural communities access to schooling. This thesis is a case study of the leadership and management challenges of multigrade schooling in a single school. The goal was to understand how education managers and leaders perceived their role in making it possible for teachers and learners to cope with multi-grade teaching. I worked in the interpretive paradigm to be able to interpret the social and cultural context of a rural, multi-grade school in the Karas region. The methods included questionnaires, interviews and observation. One of the leadership models universally considered to be available to principals of multi-grade schools is instructional leadership. My study revealed that the concept was unknown to teaching staff, although there were indications that the model had been encountered. My findings also revealed that the communication between colleges of education and the regional education department staff was very limited. One of the major issues that arose was that principals were so occupied with teaching that important issues about training/evaluation and supervision of teachers, the ‘visibility’ of the principal, setting and implementation of the aims and goals of the school and regular communication with parents and community leaders were neglected. Probably the most significant finding was that head teachers are not trained in the management of a multi-grade school, hence most if not all of the head teachers run multi-grade schools like a single-graded school. The single most important problem was that the importance of multi-grade teaching had never been highlighted, particularly in light of new staffing norms, in spite of the fact that it was a phenomenon that was likely to be a permanent arrangement.
- Full Text:
- Date Issued: 2004