The influence of indigenous languages on Ugandan English as used in the media
- Authors: Tukwasibwe, Constance
- Date: 2014
- Subjects: Mass media and language -- Uganda , Languages in contact -- Uganda , English language -- Uganda , Language transfer (Language learning) -- Uganda , Communication and culture -- Uganda , Bilingualism -- Uganda , Linguistic demography -- Uganda , Uganda -- Languages
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3646 , http://hdl.handle.net/10962/d1015637
- Description: When two or more languages come in contact, they influence each other in various ways, for example through word borrowing, transfer of sounds, morphology and syntax taken from one language system and imported to another. In this study, the primary concern is on the indigenous communities of Uganda learning the English language, plus the influence that this interaction brings into the linguistic space. Bringing the Ugandan multilingual situation into perspective, the study looks at how the English language has interacted with the local languages and the local speech habits, customs and traditions of the indigenous people, to the extent that it has been indigenized. Some word usage results in miscommunication due to the socio-cultural uniqueness of Ugandan cultural expressions. As an example, because of the practice of polygamy in most Ugandan cultures, words like co-wife are coined to mean 'a woman who shares a husband, or a husband's other wife', a word that is absent in both the language and culture of native English speakers. Furthermore some words are formed by calquing some indigenous language expressions, e.g. 'to eat money' or 'to eat cash', an expression that is calqued from the Luganda phrase, kulya sente. Such word coinages are meant to fill the 'shortfall' where the English language fails to provide adequate equivalents. Understanding the context of this kind of English usage and the influence from the indigenous languages is helpful in handling inter-cultural discourses, as the same expression may convey different senses to different people in different contexts. So then, this study deals with some peculiarities of Ugandan English, namely; the features of Ugandan English grammar which are influenced by the indigenous languages. Evidence from the Corpus of Ugandan English is explored to establish that indigenous languages in Uganda have a significant influence on the English language variety spoken in the country, and that a large part of English bilingual speakers cannot speak English without transferring the features from their mother tongue or indeed, switching and mixing codes. A British corpus was used for the purposes of comparison with Ugandan English. The research was conducted in Uganda, drawing data from English newspapers, radio and television talk -shows that were recorded to provide a structural analysis of the contact situations. The result of the study points to the fact that, indeed, the phonological, morpho-syntactic and semantic characteristics of Ugandan English have a considerable amount of influence from indigenous local languages. This study is hinged on the assumption that when indigenous languages and the target language come together in a linguistic contact situation, the resulting variety would exhibit distinct phonological, lexical, grammatical and semantic/pragmatic features ( cf. Sankoff, 2001; Thomason, 1995; Thomason & Kaufman, 1988; Winford, 2005). However, some of these innovations have attracted criticism from 'prescriptivists' such as Quirk (1985, 1988, 1990); Gaudio (2011); and Abbot (1991) who perceive them as 'nonstandard', 'incorrect English language usage' and a 'direct translation from the language user's mother tongue into English'. Yet, indigenous languages continue to play important roles in shaping the kind of English language usage in Uganda.
- Full Text:
- Date Issued: 2014
- Authors: Tukwasibwe, Constance
- Date: 2014
- Subjects: Mass media and language -- Uganda , Languages in contact -- Uganda , English language -- Uganda , Language transfer (Language learning) -- Uganda , Communication and culture -- Uganda , Bilingualism -- Uganda , Linguistic demography -- Uganda , Uganda -- Languages
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3646 , http://hdl.handle.net/10962/d1015637
- Description: When two or more languages come in contact, they influence each other in various ways, for example through word borrowing, transfer of sounds, morphology and syntax taken from one language system and imported to another. In this study, the primary concern is on the indigenous communities of Uganda learning the English language, plus the influence that this interaction brings into the linguistic space. Bringing the Ugandan multilingual situation into perspective, the study looks at how the English language has interacted with the local languages and the local speech habits, customs and traditions of the indigenous people, to the extent that it has been indigenized. Some word usage results in miscommunication due to the socio-cultural uniqueness of Ugandan cultural expressions. As an example, because of the practice of polygamy in most Ugandan cultures, words like co-wife are coined to mean 'a woman who shares a husband, or a husband's other wife', a word that is absent in both the language and culture of native English speakers. Furthermore some words are formed by calquing some indigenous language expressions, e.g. 'to eat money' or 'to eat cash', an expression that is calqued from the Luganda phrase, kulya sente. Such word coinages are meant to fill the 'shortfall' where the English language fails to provide adequate equivalents. Understanding the context of this kind of English usage and the influence from the indigenous languages is helpful in handling inter-cultural discourses, as the same expression may convey different senses to different people in different contexts. So then, this study deals with some peculiarities of Ugandan English, namely; the features of Ugandan English grammar which are influenced by the indigenous languages. Evidence from the Corpus of Ugandan English is explored to establish that indigenous languages in Uganda have a significant influence on the English language variety spoken in the country, and that a large part of English bilingual speakers cannot speak English without transferring the features from their mother tongue or indeed, switching and mixing codes. A British corpus was used for the purposes of comparison with Ugandan English. The research was conducted in Uganda, drawing data from English newspapers, radio and television talk -shows that were recorded to provide a structural analysis of the contact situations. The result of the study points to the fact that, indeed, the phonological, morpho-syntactic and semantic characteristics of Ugandan English have a considerable amount of influence from indigenous local languages. This study is hinged on the assumption that when indigenous languages and the target language come together in a linguistic contact situation, the resulting variety would exhibit distinct phonological, lexical, grammatical and semantic/pragmatic features ( cf. Sankoff, 2001; Thomason, 1995; Thomason & Kaufman, 1988; Winford, 2005). However, some of these innovations have attracted criticism from 'prescriptivists' such as Quirk (1985, 1988, 1990); Gaudio (2011); and Abbot (1991) who perceive them as 'nonstandard', 'incorrect English language usage' and a 'direct translation from the language user's mother tongue into English'. Yet, indigenous languages continue to play important roles in shaping the kind of English language usage in Uganda.
- Full Text:
- Date Issued: 2014
Curriculum outcomes, teaching practices and learner competencies in isiXhosa in three Grahamstown schools
- Authors: Fobe, Mila Pamella
- Date: 2014
- Subjects: Xhosa language -- Study and teaching (Primary) -- South Africa -- Grahamstown Xhosa language -- Study and teaching (Secondary) -- South Africa -- Grahamstown Language and education -- South Africa -- Grahamstown Curriculum planning Second language acquisition Public schools -- South Africa -- Grahamstown Language policy -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3630 , http://hdl.handle.net/10962/d1012072
- Description: This study looks at the curriculum outcomes, teaching practices and learner competencies in isiXhosa at three Eastern Cape schools and across three different grades, 7-9. It explores the link between language learning and teaching as well as the teaching strategies used within the classroom. In particular, the study seeks to analyse how isiXhosa is taught at three different levels of instruction, namely at Home Language (HL), First Additional Language (FAL) and Second Additional Language (SAL) levels. Qualitative methods were used, and the study took the form of interpretive case studies within the respective schools. The purpose of using multiple case studies was to investigate the reality within the three sites selected. The three schools had three extreme settings, in the sense that one of the schools is a rich isiXhosa environment and the other two schools are English environments. The tools used for data gathering were interviews, classroom observations, and an analysis of documents from the Department of Basic Education. Data was then presented and analysed in Chapter 4 and 5 against the backdrop of an extensive literature review in Chapter 2 as well as a detailed methodological approach as outlined in Chapter 3. One of the findings of this research indicates that in two of the schools the teaching culture is largely from a western perspective, whereas in one of the schools the learners are primarily isiXhosa speaking and teachers use a different linguistic approach to imparting knowledge. In the private and ex-Model C school it was found that a lack of exposure to isiXhosa is the primary cause of language problems for L2 learners. Secondly the L1 is not appropriately maintained or promoted in the school environment because it is presumed that learners are sufficiently exposed to their L1 at home. The research found therefore that in this particular schooling environment there is an inconsistency between the curricula that is taught in relation to the linguistic abilities of the learners, many of whom are mother tongue speakers of isiXhosa. Furthermore and more generally, it was found that teachers are still not well informed concerning South Africa’s Language-in-Education-Policy and there is a need for more inservice training that will focus on the nature of additional language acquisition in order to address the challenges of teaching these languages. The thesis concludes that extensive work needs to be done in order to reposition the teaching of isiXhosa at all three levels, but particularly at FAL level. This research shows that there is a disjuncture between the proposed curriculum/learning outcomes and the standards or levels achieved by the learners, more especially at FAL and SAL where oral proficiency in isiXhosa remains a challenge. Specific recommendations are contained in the final chapter of the thesis which also makes reference to the draft policy of the Ministry of Basic Education regarding the incremental introduction of the teaching of African languages from 2014 onwards. This thesis also makes takes as a point of departure the importance of multilingualism in a multicultural society such as South Africa where language is suggested as a strong factor in the fostering of social cohesion. It is for this reason that the thesis argues that the expert teaching of African languages, in this case isiXhosa, at both mother tongue and second language levels is of fundamental importance to the future of South African society.
- Full Text:
- Date Issued: 2014
- Authors: Fobe, Mila Pamella
- Date: 2014
- Subjects: Xhosa language -- Study and teaching (Primary) -- South Africa -- Grahamstown Xhosa language -- Study and teaching (Secondary) -- South Africa -- Grahamstown Language and education -- South Africa -- Grahamstown Curriculum planning Second language acquisition Public schools -- South Africa -- Grahamstown Language policy -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3630 , http://hdl.handle.net/10962/d1012072
- Description: This study looks at the curriculum outcomes, teaching practices and learner competencies in isiXhosa at three Eastern Cape schools and across three different grades, 7-9. It explores the link between language learning and teaching as well as the teaching strategies used within the classroom. In particular, the study seeks to analyse how isiXhosa is taught at three different levels of instruction, namely at Home Language (HL), First Additional Language (FAL) and Second Additional Language (SAL) levels. Qualitative methods were used, and the study took the form of interpretive case studies within the respective schools. The purpose of using multiple case studies was to investigate the reality within the three sites selected. The three schools had three extreme settings, in the sense that one of the schools is a rich isiXhosa environment and the other two schools are English environments. The tools used for data gathering were interviews, classroom observations, and an analysis of documents from the Department of Basic Education. Data was then presented and analysed in Chapter 4 and 5 against the backdrop of an extensive literature review in Chapter 2 as well as a detailed methodological approach as outlined in Chapter 3. One of the findings of this research indicates that in two of the schools the teaching culture is largely from a western perspective, whereas in one of the schools the learners are primarily isiXhosa speaking and teachers use a different linguistic approach to imparting knowledge. In the private and ex-Model C school it was found that a lack of exposure to isiXhosa is the primary cause of language problems for L2 learners. Secondly the L1 is not appropriately maintained or promoted in the school environment because it is presumed that learners are sufficiently exposed to their L1 at home. The research found therefore that in this particular schooling environment there is an inconsistency between the curricula that is taught in relation to the linguistic abilities of the learners, many of whom are mother tongue speakers of isiXhosa. Furthermore and more generally, it was found that teachers are still not well informed concerning South Africa’s Language-in-Education-Policy and there is a need for more inservice training that will focus on the nature of additional language acquisition in order to address the challenges of teaching these languages. The thesis concludes that extensive work needs to be done in order to reposition the teaching of isiXhosa at all three levels, but particularly at FAL level. This research shows that there is a disjuncture between the proposed curriculum/learning outcomes and the standards or levels achieved by the learners, more especially at FAL and SAL where oral proficiency in isiXhosa remains a challenge. Specific recommendations are contained in the final chapter of the thesis which also makes reference to the draft policy of the Ministry of Basic Education regarding the incremental introduction of the teaching of African languages from 2014 onwards. This thesis also makes takes as a point of departure the importance of multilingualism in a multicultural society such as South Africa where language is suggested as a strong factor in the fostering of social cohesion. It is for this reason that the thesis argues that the expert teaching of African languages, in this case isiXhosa, at both mother tongue and second language levels is of fundamental importance to the future of South African society.
- Full Text:
- Date Issued: 2014
Building Information Modelling as a catalyst for an Integrated Construction Project Delivery culture in South Africa
- Authors: Froise, Timothy
- Date: 2014
- Subjects: Construction industry -- South Africa , Construction projects -- South Africa , Acculturation -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:9716 , http://hdl.handle.net/10948/d1020872
- Description: The importance of technology in construction partnering agreements has been recognised as a vital part of integrated project delivery (IPD) philosophy. Building information modelling (BIM) is increasingly being used by consultants in South Africa during the design phase of construction projects. However, its use is generally not aimed at an integrated project delivery approach, but rather as a tool to generate documentation, as BIM is generally more efficient than traditional computer aided design (CAD) software. For the full benefits of BIM to be realised, a greater degree of acculturation is required between construction project organisations (CPOs). The current cultures of CPOs are separationist in nature and tend to inhibit acculturation within the industry. BIM provides a central source of information that can improve communications between CPOs and foster a collaborative culture. The research examines IPD and BIM in the South African context and investigates how BIM can contribute to IPD. A survey was conducted among registered contractors from the three top grades and architecture practices from two regions in South Africa. The survey was placed in context by a case study that analysed the use of BIM and the resulting communication network seen in a public works project using typical procurement methods. The associated problems with the current accepted paradigm are illuminated by the research.
- Full Text:
- Date Issued: 2014
- Authors: Froise, Timothy
- Date: 2014
- Subjects: Construction industry -- South Africa , Construction projects -- South Africa , Acculturation -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:9716 , http://hdl.handle.net/10948/d1020872
- Description: The importance of technology in construction partnering agreements has been recognised as a vital part of integrated project delivery (IPD) philosophy. Building information modelling (BIM) is increasingly being used by consultants in South Africa during the design phase of construction projects. However, its use is generally not aimed at an integrated project delivery approach, but rather as a tool to generate documentation, as BIM is generally more efficient than traditional computer aided design (CAD) software. For the full benefits of BIM to be realised, a greater degree of acculturation is required between construction project organisations (CPOs). The current cultures of CPOs are separationist in nature and tend to inhibit acculturation within the industry. BIM provides a central source of information that can improve communications between CPOs and foster a collaborative culture. The research examines IPD and BIM in the South African context and investigates how BIM can contribute to IPD. A survey was conducted among registered contractors from the three top grades and architecture practices from two regions in South Africa. The survey was placed in context by a case study that analysed the use of BIM and the resulting communication network seen in a public works project using typical procurement methods. The associated problems with the current accepted paradigm are illuminated by the research.
- Full Text:
- Date Issued: 2014
Separation of rhodium (III) and iridium (IV) using functional polymeric materials
- Authors: Majavu, Avela
- Date: 2014
- Subjects: Rhodium -- Separation , Iridium -- Separation
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/6576 , vital:21116
- Description: Poly(vinylbenzylchloride) (PVBC) nanofibers were fabricated by the electrospinning process. The Merrifield micropheres, silica microsparticles and PVBC nanofibers were functionalised with different quaternary diammonium groups derived from ethylenediamine (EDA), tetramethylenediamine (TMDA), hexamethylenediamine (HMDA), 1,8-diaminooctane (OMDA), 1,10-diaminodecane (DMDA) and 1,12-diaminododecane (DDMDA) and investigated for separation of [RhCl5(H2O)]2- and [IrCl6]2-. The sorbent materials were characterised by means of FTIR, XPS, SEM, BET surface area, thermogravimetric analysis and elemental analysis, and characterization results showed that the functionalization of the sorbent materials was successful. Batch equilibrium studies were carried out to assess the efficiency of these different anion exchangers using single metal aqueous solutions. The adsorption isotherms and kinetics of both [RhCl5(H2O)]2- and [IrCl6]2- adsorption onto the sorbent materials are presented. The isothermal batch adsorption studies fitted the Freundlich model indicating heterogeneous surface adsorption. The Freundlich isotherm confirmed multilayer adsorption and the Freundlich constant (kf) displayed the following ascending order for nanofibers (F-QUAT EDA, F-QUAT TMDA, F-QUAT HMDA, F-QUAT OMDA and F-QUAT DMDA), silica microparticles (Si-QUAT EDA, Si-QUAT TMDA, Si-QUAT HMDA, Si-QUAT OMDA and Si-QUAT DMDA) and microspheres (B-QUAT EDA, B-QUAT TMDA, B-QUAT HMDA, B-QUAT OMDA and B-QUAT DMDA) and a decrease in kf for F-QUAT DDMDA, Si-QUAT DDMDA and B-QUAT DDMDA has been observed. The pseudo second-order model was found to be the best fit to describe the adsorption kinetics of both metal ions complexes onto all the sorbent materials. K2 value in pseudo second-order kinetics showed that the rate constant for adsorption of [IrCl6]2- onto nanofibers was larger than for silica microparticles and Merrifield microspheres. Column sorption of [IrCl6]2- and [RhCl5(H2O)]2- was carried out and the loading capacities of [IrCl6]2- were obtained, and they showed dependence on the length of the methylene spacer between the two diammonium centres. [RhCl5(H2O)]2- was not adsorbed by the sorbent materials while [IrCl6]2- was loaded onto the column. The highest iridium loading capacities for all the sorbent materials for the diamines with decylene spacer, and were found to be 32.94 mg/g, 29.35 mg/g, and 27.09 mg/g for F-QUAT DMDA, Si-QUAT DMDA and B-QUAT DMDA respectively. It was also observed on the derivatives of DMDA supported on nanofibers that F-QUAT ethyl loading capacity for iridium (19.89 mg/g) reduced which may be due to the electron-donating nature of the ethyl group and the increase of hydrophobicity whereas F-QUAT benzyl loading capacity (244.64 mg/g) increased dramatically due to increase in the size of the cation which lowers the positive charge density of the quaternary diammonium center. The charge delocalizing ability of the benzyl group resulted in the best interaction of the diammonium group derived from this quaternizing agent, yielding the highest loading capacity for [IrCl6]2-. Reusability was conducted and the results showed that the all the sorbent materials can be used repeatedly without decreasing their adsorption capacity significantly. The neat diammonium salts were also synthesized and interacted with the chorido metal complex anions to form ion-pairs which were then studied for their solubility. The synthesis of the quaternary salts was rather challenging and resulted in some interesting species when impurities of the iodide form of the salts were present in the process of converting them to the iodide form. Some of these include I52+, which was confirmed preliminarily by X-ray structural analysis, potentiometry and cyclic voltammetry. Molecular modeling studies were also conducted to explain the interaction of the chlorido anions with the cationic diammonium centres, and to quantify these interactions by thermodynamic parameters, partial charge calculations, dipole moments and electrostatic potentials, and there was good agreement between theory and experiment. This thesis presents iridium-specific materials that could be applied in solutions of secondary PMGs sources containing rhodium and iridium as well as in feed solutions from ore processing.
- Full Text:
- Date Issued: 2014
- Authors: Majavu, Avela
- Date: 2014
- Subjects: Rhodium -- Separation , Iridium -- Separation
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/6576 , vital:21116
- Description: Poly(vinylbenzylchloride) (PVBC) nanofibers were fabricated by the electrospinning process. The Merrifield micropheres, silica microsparticles and PVBC nanofibers were functionalised with different quaternary diammonium groups derived from ethylenediamine (EDA), tetramethylenediamine (TMDA), hexamethylenediamine (HMDA), 1,8-diaminooctane (OMDA), 1,10-diaminodecane (DMDA) and 1,12-diaminododecane (DDMDA) and investigated for separation of [RhCl5(H2O)]2- and [IrCl6]2-. The sorbent materials were characterised by means of FTIR, XPS, SEM, BET surface area, thermogravimetric analysis and elemental analysis, and characterization results showed that the functionalization of the sorbent materials was successful. Batch equilibrium studies were carried out to assess the efficiency of these different anion exchangers using single metal aqueous solutions. The adsorption isotherms and kinetics of both [RhCl5(H2O)]2- and [IrCl6]2- adsorption onto the sorbent materials are presented. The isothermal batch adsorption studies fitted the Freundlich model indicating heterogeneous surface adsorption. The Freundlich isotherm confirmed multilayer adsorption and the Freundlich constant (kf) displayed the following ascending order for nanofibers (F-QUAT EDA, F-QUAT TMDA, F-QUAT HMDA, F-QUAT OMDA and F-QUAT DMDA), silica microparticles (Si-QUAT EDA, Si-QUAT TMDA, Si-QUAT HMDA, Si-QUAT OMDA and Si-QUAT DMDA) and microspheres (B-QUAT EDA, B-QUAT TMDA, B-QUAT HMDA, B-QUAT OMDA and B-QUAT DMDA) and a decrease in kf for F-QUAT DDMDA, Si-QUAT DDMDA and B-QUAT DDMDA has been observed. The pseudo second-order model was found to be the best fit to describe the adsorption kinetics of both metal ions complexes onto all the sorbent materials. K2 value in pseudo second-order kinetics showed that the rate constant for adsorption of [IrCl6]2- onto nanofibers was larger than for silica microparticles and Merrifield microspheres. Column sorption of [IrCl6]2- and [RhCl5(H2O)]2- was carried out and the loading capacities of [IrCl6]2- were obtained, and they showed dependence on the length of the methylene spacer between the two diammonium centres. [RhCl5(H2O)]2- was not adsorbed by the sorbent materials while [IrCl6]2- was loaded onto the column. The highest iridium loading capacities for all the sorbent materials for the diamines with decylene spacer, and were found to be 32.94 mg/g, 29.35 mg/g, and 27.09 mg/g for F-QUAT DMDA, Si-QUAT DMDA and B-QUAT DMDA respectively. It was also observed on the derivatives of DMDA supported on nanofibers that F-QUAT ethyl loading capacity for iridium (19.89 mg/g) reduced which may be due to the electron-donating nature of the ethyl group and the increase of hydrophobicity whereas F-QUAT benzyl loading capacity (244.64 mg/g) increased dramatically due to increase in the size of the cation which lowers the positive charge density of the quaternary diammonium center. The charge delocalizing ability of the benzyl group resulted in the best interaction of the diammonium group derived from this quaternizing agent, yielding the highest loading capacity for [IrCl6]2-. Reusability was conducted and the results showed that the all the sorbent materials can be used repeatedly without decreasing their adsorption capacity significantly. The neat diammonium salts were also synthesized and interacted with the chorido metal complex anions to form ion-pairs which were then studied for their solubility. The synthesis of the quaternary salts was rather challenging and resulted in some interesting species when impurities of the iodide form of the salts were present in the process of converting them to the iodide form. Some of these include I52+, which was confirmed preliminarily by X-ray structural analysis, potentiometry and cyclic voltammetry. Molecular modeling studies were also conducted to explain the interaction of the chlorido anions with the cationic diammonium centres, and to quantify these interactions by thermodynamic parameters, partial charge calculations, dipole moments and electrostatic potentials, and there was good agreement between theory and experiment. This thesis presents iridium-specific materials that could be applied in solutions of secondary PMGs sources containing rhodium and iridium as well as in feed solutions from ore processing.
- Full Text:
- Date Issued: 2014
Purification and characterization of TbHsp70.c, a novel Hsp70 from Trypanosoma brucei
- Authors: Burger, Adélle
- Date: 2014
- Subjects: African trypanosomiasis -- Research Heat shock proteins -- Research Trypanosoma brucei -- Research Mycobacterial diseases -- Research -- Africa Parasitic diseases -- Africa -- Prevention Parasites -- Physiology Developing countries -- Economic conditions
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4105 , http://hdl.handle.net/10962/d1011618
- Description: One of Africa’s neglected tropical diseases, African Trypanosomiasis, is not only fatal but also has a crippling impact on economic development. Heat shock proteins play a wide range of roles in the cell and they are required to assist the parasite as it moves from a cold blooded insect vector to a warm blooded mammalian host. The expression of heat shock proteins increases during these heat shock conditions, and this is considered to play a role in differentiation of these vector-borne parasites. Heat shock protein 70 (Hsp70) is an important molecular chaperone that is involved in protein homeostasis, Hsp40 acts as a co-chaperone and stimulates its intrinsically weak ATPase activity. In silico analysis of the T. brucei genome has revealed the existence of 12 Hsp70 proteins and 65 Hsp40 proteins to date. A novel Hsp70, TbHsp70.c, was recently identified in T. brucei. Different from the prototypical Hsp70, TbHsp70.c contains an acidic substrate binding domain and lacks the C-terminal EEVD motif. By implication the substrate range and mechanism by which the substrates are recognized may be novel. The ability of a Type I Hsp40, Tbj2, to function as a co-chaperone of TbHsp70.c was investigated. The main objective of this study was to biochemically characterize TbHsp70.c and its partnership with Tbj2 to further enhance our knowledge of parasite biology. TbHsp70.c and Tbj2 were heterologously expressed and purified and both proteins displayed chaperone activities in their ability to suppress aggregation of thermolabile MDH. TbHsp70.c also suppressed aggregation of rhodanese. ATPase assays revealed that the ATPase activity of TbHsp70.c was stimulated by Tbj2. The targeted inhibition of the function of heat shock proteins is emerging as a tool to combat disease. The small molecule modulators quercetin and methylene blue are known to inhibit the ATPase activity of Hsp70. However, methylene blue did not significantly inhibit the ATPase activity of TbHsp70.c; while quercetin, did inhibit the ATPase activity. In vivo heat stress experiments indicated an up-regulation of the expression levels of TbHsp70.c. RNA interference studies showed partial knockdown of TbHsp70.c with no detrimental effect on the parasite. Fluorescence microscopy studies of TbHsp70.c showed a probable cytoplasmic subcellular localization. In this study both TbHsp70.c and Tbj2 demonstrated chaperone activity and Tbj2 possibly functions as a co-chaperone of TbHsp70.c.
- Full Text:
- Date Issued: 2014
- Authors: Burger, Adélle
- Date: 2014
- Subjects: African trypanosomiasis -- Research Heat shock proteins -- Research Trypanosoma brucei -- Research Mycobacterial diseases -- Research -- Africa Parasitic diseases -- Africa -- Prevention Parasites -- Physiology Developing countries -- Economic conditions
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4105 , http://hdl.handle.net/10962/d1011618
- Description: One of Africa’s neglected tropical diseases, African Trypanosomiasis, is not only fatal but also has a crippling impact on economic development. Heat shock proteins play a wide range of roles in the cell and they are required to assist the parasite as it moves from a cold blooded insect vector to a warm blooded mammalian host. The expression of heat shock proteins increases during these heat shock conditions, and this is considered to play a role in differentiation of these vector-borne parasites. Heat shock protein 70 (Hsp70) is an important molecular chaperone that is involved in protein homeostasis, Hsp40 acts as a co-chaperone and stimulates its intrinsically weak ATPase activity. In silico analysis of the T. brucei genome has revealed the existence of 12 Hsp70 proteins and 65 Hsp40 proteins to date. A novel Hsp70, TbHsp70.c, was recently identified in T. brucei. Different from the prototypical Hsp70, TbHsp70.c contains an acidic substrate binding domain and lacks the C-terminal EEVD motif. By implication the substrate range and mechanism by which the substrates are recognized may be novel. The ability of a Type I Hsp40, Tbj2, to function as a co-chaperone of TbHsp70.c was investigated. The main objective of this study was to biochemically characterize TbHsp70.c and its partnership with Tbj2 to further enhance our knowledge of parasite biology. TbHsp70.c and Tbj2 were heterologously expressed and purified and both proteins displayed chaperone activities in their ability to suppress aggregation of thermolabile MDH. TbHsp70.c also suppressed aggregation of rhodanese. ATPase assays revealed that the ATPase activity of TbHsp70.c was stimulated by Tbj2. The targeted inhibition of the function of heat shock proteins is emerging as a tool to combat disease. The small molecule modulators quercetin and methylene blue are known to inhibit the ATPase activity of Hsp70. However, methylene blue did not significantly inhibit the ATPase activity of TbHsp70.c; while quercetin, did inhibit the ATPase activity. In vivo heat stress experiments indicated an up-regulation of the expression levels of TbHsp70.c. RNA interference studies showed partial knockdown of TbHsp70.c with no detrimental effect on the parasite. Fluorescence microscopy studies of TbHsp70.c showed a probable cytoplasmic subcellular localization. In this study both TbHsp70.c and Tbj2 demonstrated chaperone activity and Tbj2 possibly functions as a co-chaperone of TbHsp70.c.
- Full Text:
- Date Issued: 2014
Can expansive (social) learning processes strengthen organisational learning for improved wetland management in a plantation forestry company, and if so how? : a case study of Mondi
- Authors: Lindley, David Stewart
- Date: 2014
- Subjects: Mondi Group , Wetland management -- South Africa , Wetland conservation -- Study and teaching (Continuing education) , Employees -- Training of -- South Africa , Action theory , Critical realism , Social learning , Environmental education -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2003 , http://hdl.handle.net/10962/d1015661
- Description: Mondi is an international packaging and paper company that manages over 300 000 ha of land in South Africa. After over a decade of working with Mondi to improve its wetland management, wetland sustainability practices were still not integrated into the broader forestry operations, despite some significant cases of successful wetland rehabilitation. An interventionist research project was therefore conducted to explore the factors inhibiting improved wetland management, and determine if and how expansive social learning processes could strengthen organisational learning and development to overcome these factors. In doing so, the research has investigated how informal adult learning supports organisational change to strengthen wetland and environmental sustainability practices, within a corporate plantation forestry context. How individual and/or group-based learning interactions translate to the collective, at the level of organisational change was a key issue probed in this study. The following three research questions were used to guide the research: 1. What tensions and contradictions exist in wetland management in a plantation forestry company? 2. Can expansive learning begin to address the tensions and contradictions that exist in wetland management in a plantation forestry company, for improved sustainability practices? 3. Can expansive social learning strengthen organisational learning and development, enabling Mondi to improve its wetland sustainability practices, and if so how does it do this? Cultural historical activity theory (CHAT) and the theory of expansive learning provided an epistemological framework for the research. The philosophy of critical realism gave ontological depth to the research, and contributed to a deeper understanding of CHAT and expansive learning. Critical realism was therefore used as a philosophy to underlabour the theoretical framework of the research. However CHAT and expansive learning could not provide the depth of detail required to explain how the expansive learning, organisational social change, and boundary crossings that are necessary for assembling the collective were taking place. Realist social theory (developed out of critical realism by Margaret Archer as an ontologically located theory of how and why social change occurs, or does not) supported the research to do this. The morphogenetic framework was used as a methodology for applying realist social theory. The expansive learning cycle was used as a methodology for applying CHAT and the theory of expansive learning; guiding the development of new knowledge creation required by Mondi staff to identify contradictions and associated tensions inhibiting wetland management, understand their root causes, and develop solutions. Through the expansive learning process, the tensions and contradictions become generative as a tool supporting expansive social learning, rather than as a means to an end where universal consensus was reached on how to circumvent the contradictions. The research was conducted in five phases: • Phase 1: Contextual profiling to identify and describe three activity systems in Mondi responsible for wetland management: 1) siviculture foresters; 2) environmental specialists; 3) community engagement facilitators. The data was generated and analysed through through document analysis, 17 interviews, 2nd generation CHAT analysis, and Critical Realist generative mechanism analysis; • Phase 2: Analysis and identification of tensions and contradictions through a first interventionist workshop. Modelling new solutions to deal with contractions, and examining and testing new models in and after the second interventionist workshop; • Phase 3: Implementing new models as wetland management projects and involved project implementation. This included boundary crossing practices of staff in the three activity systems, reflection and re-view in a further five progress review/interventionist workshops, and a management meeting and seminar; • Phase 4: Reflecting on the expansive learning process, results, and consolidation of changed practices, through nine reflective interviews and field observations; • Phase 5: Morphogenic/stasis analysis of the organisational change and development catalysed via the expansive social learning process (or not). The research found that expansive social learning processes supported organisational learning and development for improved wetland management by: 1) strengthening the scope, depth, and sophistication of participant understanding; 2) expanding the ways staff interact and collaboratively work together; 3) democratising decision making; 4) improving social relations between staff, reducing power differentials, and creating stronger relationships; 5) enhancing participant reflexivity through deeper understanding of social structures and cultural systems, and changing them to support improved wetland and environmental practice of staff, and developing the organisational structures and processes to strengthen organisational learning and development; and 6) using the contradictions identified as generative mechanisms to stimulate and catalyse organisational learning and development for changed wetland/environmental management.
- Full Text:
- Date Issued: 2014
- Authors: Lindley, David Stewart
- Date: 2014
- Subjects: Mondi Group , Wetland management -- South Africa , Wetland conservation -- Study and teaching (Continuing education) , Employees -- Training of -- South Africa , Action theory , Critical realism , Social learning , Environmental education -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2003 , http://hdl.handle.net/10962/d1015661
- Description: Mondi is an international packaging and paper company that manages over 300 000 ha of land in South Africa. After over a decade of working with Mondi to improve its wetland management, wetland sustainability practices were still not integrated into the broader forestry operations, despite some significant cases of successful wetland rehabilitation. An interventionist research project was therefore conducted to explore the factors inhibiting improved wetland management, and determine if and how expansive social learning processes could strengthen organisational learning and development to overcome these factors. In doing so, the research has investigated how informal adult learning supports organisational change to strengthen wetland and environmental sustainability practices, within a corporate plantation forestry context. How individual and/or group-based learning interactions translate to the collective, at the level of organisational change was a key issue probed in this study. The following three research questions were used to guide the research: 1. What tensions and contradictions exist in wetland management in a plantation forestry company? 2. Can expansive learning begin to address the tensions and contradictions that exist in wetland management in a plantation forestry company, for improved sustainability practices? 3. Can expansive social learning strengthen organisational learning and development, enabling Mondi to improve its wetland sustainability practices, and if so how does it do this? Cultural historical activity theory (CHAT) and the theory of expansive learning provided an epistemological framework for the research. The philosophy of critical realism gave ontological depth to the research, and contributed to a deeper understanding of CHAT and expansive learning. Critical realism was therefore used as a philosophy to underlabour the theoretical framework of the research. However CHAT and expansive learning could not provide the depth of detail required to explain how the expansive learning, organisational social change, and boundary crossings that are necessary for assembling the collective were taking place. Realist social theory (developed out of critical realism by Margaret Archer as an ontologically located theory of how and why social change occurs, or does not) supported the research to do this. The morphogenetic framework was used as a methodology for applying realist social theory. The expansive learning cycle was used as a methodology for applying CHAT and the theory of expansive learning; guiding the development of new knowledge creation required by Mondi staff to identify contradictions and associated tensions inhibiting wetland management, understand their root causes, and develop solutions. Through the expansive learning process, the tensions and contradictions become generative as a tool supporting expansive social learning, rather than as a means to an end where universal consensus was reached on how to circumvent the contradictions. The research was conducted in five phases: • Phase 1: Contextual profiling to identify and describe three activity systems in Mondi responsible for wetland management: 1) siviculture foresters; 2) environmental specialists; 3) community engagement facilitators. The data was generated and analysed through through document analysis, 17 interviews, 2nd generation CHAT analysis, and Critical Realist generative mechanism analysis; • Phase 2: Analysis and identification of tensions and contradictions through a first interventionist workshop. Modelling new solutions to deal with contractions, and examining and testing new models in and after the second interventionist workshop; • Phase 3: Implementing new models as wetland management projects and involved project implementation. This included boundary crossing practices of staff in the three activity systems, reflection and re-view in a further five progress review/interventionist workshops, and a management meeting and seminar; • Phase 4: Reflecting on the expansive learning process, results, and consolidation of changed practices, through nine reflective interviews and field observations; • Phase 5: Morphogenic/stasis analysis of the organisational change and development catalysed via the expansive social learning process (or not). The research found that expansive social learning processes supported organisational learning and development for improved wetland management by: 1) strengthening the scope, depth, and sophistication of participant understanding; 2) expanding the ways staff interact and collaboratively work together; 3) democratising decision making; 4) improving social relations between staff, reducing power differentials, and creating stronger relationships; 5) enhancing participant reflexivity through deeper understanding of social structures and cultural systems, and changing them to support improved wetland and environmental practice of staff, and developing the organisational structures and processes to strengthen organisational learning and development; and 6) using the contradictions identified as generative mechanisms to stimulate and catalyse organisational learning and development for changed wetland/environmental management.
- Full Text:
- Date Issued: 2014
Establishing a formulation design space for a generic clobetasol 17- propionate cream using the principles of quality by design
- Fauzee, Ayeshah Fateemah Beebee
- Authors: Fauzee, Ayeshah Fateemah Beebee
- Date: 2014
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:20983 , http://hdl.handle.net/10962/5868
- Description: The pharmaceutical industry is global, is highly regulated and is able to achieve reasonable product quality but at high cost with maximum effort. Numerous challenges face the pharmaceutical industry and include a shrinking research pipeline, less innovation, outsourcing, investments, increasing research and development costs, long approval times, growth of the generic industry, failure to understand or analyze manufacturing failure and wastage as high at fifty percent for some pharmaceutical products. An efficient and flexible pharmaceutical sector should be able to consistently produce high quality pharmaceutical products at a reduced cost with minimal waste. As a result, Food and Drug Administration (FDA) and other agencies such as the International Conference on Harmonization (ICH) have embraced a “Quality by Design” (QbD) paradigm and this has become the “desired state” so as to shift manufacturing from being empirical to a science, engineering, and risk based approach. QbD is a systematic approach for the development of high quality pharmaceutical dosage forms that begins with predefined objectives based on the premise that quality must be built into and not tested into a product. QbD together with the establishment of a design space for dosage forms is a fairly new concept and there is limited published data on QbD concepts that report the entire process of identifying Critical Quality Attributes (CQA), design of a formulation and manufacturing process to meet product CQA, understanding the impact of material attributes and process parameters on product CQA, identification and controlling sources of variability in materials and processes that affect the CQA of a product and finally establishing, evaluating and testing a design space using both in vitro and in vivo approaches to assure that a product of consistent quality can always be produced. The objective of these studies was to implement a QbD approach to establish a design space for the development and manufacture of a safe, effective, stable generic formulation containing 0.05% w/w clobetasol 17-propionate (CP) that had similar in vitro and in vivo characteristics to an innovator product, Dermovate® (Sekpharma® Pty Ltd, Sandton, Gauteng, RSA). Such a product would pose a minimal risk of failure when treating severe skin disorders such as seborrhoeic dermatitis, extreme photodermatitis and/or severe psoriasis in HIV/AIDS patients in Southern Africa.
- Full Text:
- Date Issued: 2014
- Authors: Fauzee, Ayeshah Fateemah Beebee
- Date: 2014
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:20983 , http://hdl.handle.net/10962/5868
- Description: The pharmaceutical industry is global, is highly regulated and is able to achieve reasonable product quality but at high cost with maximum effort. Numerous challenges face the pharmaceutical industry and include a shrinking research pipeline, less innovation, outsourcing, investments, increasing research and development costs, long approval times, growth of the generic industry, failure to understand or analyze manufacturing failure and wastage as high at fifty percent for some pharmaceutical products. An efficient and flexible pharmaceutical sector should be able to consistently produce high quality pharmaceutical products at a reduced cost with minimal waste. As a result, Food and Drug Administration (FDA) and other agencies such as the International Conference on Harmonization (ICH) have embraced a “Quality by Design” (QbD) paradigm and this has become the “desired state” so as to shift manufacturing from being empirical to a science, engineering, and risk based approach. QbD is a systematic approach for the development of high quality pharmaceutical dosage forms that begins with predefined objectives based on the premise that quality must be built into and not tested into a product. QbD together with the establishment of a design space for dosage forms is a fairly new concept and there is limited published data on QbD concepts that report the entire process of identifying Critical Quality Attributes (CQA), design of a formulation and manufacturing process to meet product CQA, understanding the impact of material attributes and process parameters on product CQA, identification and controlling sources of variability in materials and processes that affect the CQA of a product and finally establishing, evaluating and testing a design space using both in vitro and in vivo approaches to assure that a product of consistent quality can always be produced. The objective of these studies was to implement a QbD approach to establish a design space for the development and manufacture of a safe, effective, stable generic formulation containing 0.05% w/w clobetasol 17-propionate (CP) that had similar in vitro and in vivo characteristics to an innovator product, Dermovate® (Sekpharma® Pty Ltd, Sandton, Gauteng, RSA). Such a product would pose a minimal risk of failure when treating severe skin disorders such as seborrhoeic dermatitis, extreme photodermatitis and/or severe psoriasis in HIV/AIDS patients in Southern Africa.
- Full Text:
- Date Issued: 2014
Perceived value creation in technology-based entrepreneurial businesses
- Van den Heever, Thomas Stanley
- Authors: Van den Heever, Thomas Stanley
- Date: 2014
- Subjects: New business enterprises , Entrepreneurship , Technological innovations -- Management
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:9329 , http://hdl.handle.net/10948/d1021047
- Description: Small entrepreneurial businesses are widely regarded as important contributors to the economic well-being of countries all over the world as they create value for both the entrepreneur and the economy in which they operate. The value creation process in these businesses often differs from what commonly happens in larger established businesses. Resources available to the entrepreneur are normally much more restricted and decisions are often based on limited information. This thesis focuses on the value that is created by technology-based entrepreneurial businesses, the leveraging of limited resources and the decision-making orientation they adopt during this process. Given the importance of technology-based entrepreneurial businesses in contributing to economic growth and job creation in most global economies, as well as the limited previous research conducted amongst these businesses, the purpose of this study was to identify the human and social capital factors influencing value creation in technology-based entrepreneurial businesses. With this purpose in mind, the primary objective was to identify, investigate and empirically test the relationships between the various identified factors and Perceived value creation in technology-based entrepreneurial businesses, taking into account their decision-making orientation, as well as the uncertain environment under which they operate. This study uses the Resource-Based View of the business as the basis of its theoretical orientation. The literature review revealed five main categories of constructs, namely Knowledge and skills, Experience, Networks, Decision-making orientation and Perceived environmental uncertainty influencing the dependent variable Perceived value creation in technology-based entrepreneurial businesses. Knowledge and skills, Experience and Networks were identified as independent variables while Decision-making orientation was identified as the mediating variable and Perceived environmental uncertainty as the moderating variable. Six demographic variables (type of industry, age of business, number of employees, age of entrepreneur, academic qualifications of entrepreneur and the number of previous businesses started by the entrepreneur) were also identified as potential influencing factors. Various hypotheses were formulated to be tested during the empirical investigation. Each construct was clearly defined and then operationalised. Operationalisation was done by using reliable and valid items sourced from tested measuring instruments used in previous studies, as well as a number of self-generated items based on secondary sources. A structured questionnaire was made available to respondents identified by means of the convenience snowball sampling technique, and the data collected from 313 usable questionnaires was subjected to various statistical analyses. An Exploratory Factor Analyses (EFA) was conducted which confirmed the different variables, and Cronbach-alpha coefficients were calculated to confirm the reliability of the measuring instrument. Structural Equation Modelling (SEM) was the main statistical procedure used to test the significance of the relationships hypothesised between the various independent, mediating, moderating and dependent variables. A number of different models were tested, and the results discussed and explained. The main finding of the study was that technology-based entrepreneurial business can create financial and non-financial value by adopting a decision-making orientation in the business of co-creating the future with other stakeholders. The most important human and social capital factors that influence the decision-making orientation of these businesses are Knowledge and skills, Unstructured networks and Structured networks. The main limitations of the study were firstly the convenience snowball sampling technique used to collect responses, secondly the dependence of reporting on organisation issues by individuals, and thirdly the limited number of influencing factors included in the models. Future research should address these limitations, and could include qualitative analyses. This study has added to the empirical body of knowledge on entrepreneurship research by investigating a particularly important segment of the literature, namely technology-based entrepreneurial businesses. By identifying and developing various models that outline the most significant factors that influence perceived value creation in technology-based entrepreneurial businesses, this study offers recommendations and suggestions for managing these businesses in such a way as to improve the creation of financial and non-financial value in them. It further provides recommendations for business teaching programmes to enhance curriculums by focusing on alternatives to the format of formal business planning.
- Full Text:
- Date Issued: 2014
- Authors: Van den Heever, Thomas Stanley
- Date: 2014
- Subjects: New business enterprises , Entrepreneurship , Technological innovations -- Management
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:9329 , http://hdl.handle.net/10948/d1021047
- Description: Small entrepreneurial businesses are widely regarded as important contributors to the economic well-being of countries all over the world as they create value for both the entrepreneur and the economy in which they operate. The value creation process in these businesses often differs from what commonly happens in larger established businesses. Resources available to the entrepreneur are normally much more restricted and decisions are often based on limited information. This thesis focuses on the value that is created by technology-based entrepreneurial businesses, the leveraging of limited resources and the decision-making orientation they adopt during this process. Given the importance of technology-based entrepreneurial businesses in contributing to economic growth and job creation in most global economies, as well as the limited previous research conducted amongst these businesses, the purpose of this study was to identify the human and social capital factors influencing value creation in technology-based entrepreneurial businesses. With this purpose in mind, the primary objective was to identify, investigate and empirically test the relationships between the various identified factors and Perceived value creation in technology-based entrepreneurial businesses, taking into account their decision-making orientation, as well as the uncertain environment under which they operate. This study uses the Resource-Based View of the business as the basis of its theoretical orientation. The literature review revealed five main categories of constructs, namely Knowledge and skills, Experience, Networks, Decision-making orientation and Perceived environmental uncertainty influencing the dependent variable Perceived value creation in technology-based entrepreneurial businesses. Knowledge and skills, Experience and Networks were identified as independent variables while Decision-making orientation was identified as the mediating variable and Perceived environmental uncertainty as the moderating variable. Six demographic variables (type of industry, age of business, number of employees, age of entrepreneur, academic qualifications of entrepreneur and the number of previous businesses started by the entrepreneur) were also identified as potential influencing factors. Various hypotheses were formulated to be tested during the empirical investigation. Each construct was clearly defined and then operationalised. Operationalisation was done by using reliable and valid items sourced from tested measuring instruments used in previous studies, as well as a number of self-generated items based on secondary sources. A structured questionnaire was made available to respondents identified by means of the convenience snowball sampling technique, and the data collected from 313 usable questionnaires was subjected to various statistical analyses. An Exploratory Factor Analyses (EFA) was conducted which confirmed the different variables, and Cronbach-alpha coefficients were calculated to confirm the reliability of the measuring instrument. Structural Equation Modelling (SEM) was the main statistical procedure used to test the significance of the relationships hypothesised between the various independent, mediating, moderating and dependent variables. A number of different models were tested, and the results discussed and explained. The main finding of the study was that technology-based entrepreneurial business can create financial and non-financial value by adopting a decision-making orientation in the business of co-creating the future with other stakeholders. The most important human and social capital factors that influence the decision-making orientation of these businesses are Knowledge and skills, Unstructured networks and Structured networks. The main limitations of the study were firstly the convenience snowball sampling technique used to collect responses, secondly the dependence of reporting on organisation issues by individuals, and thirdly the limited number of influencing factors included in the models. Future research should address these limitations, and could include qualitative analyses. This study has added to the empirical body of knowledge on entrepreneurship research by investigating a particularly important segment of the literature, namely technology-based entrepreneurial businesses. By identifying and developing various models that outline the most significant factors that influence perceived value creation in technology-based entrepreneurial businesses, this study offers recommendations and suggestions for managing these businesses in such a way as to improve the creation of financial and non-financial value in them. It further provides recommendations for business teaching programmes to enhance curriculums by focusing on alternatives to the format of formal business planning.
- Full Text:
- Date Issued: 2014
Mobilising processes of abstraction, experiential learning and representation of traditional ecological knowledge in participatory monitoring of mangroves and fisheries : an approach towards enhancing social learning processes on the eastern coast of Tanzania
- Authors: Sabai, Daniel
- Date: 2014
- Subjects: Traditional ecological knowledge , Environmental education -- Tanzania , Environmental education -- Study and teaching -- Tanzania , Coastal zone management -- Tanzania , Social learning -- Tanzania , Experiential learning -- Tanzania , Mangrove conservation -- Tanzania , Fishery management -- Tanzania
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1979 , http://hdl.handle.net/10962/d1013060
- Description: This study addresses a core problem that was uncovered in records from coastal management monitoring initiatives on the eastern coast of Tanzania associated with the application and use of coastal monitoring indicators developed by external development partners for the coastal zone. These records suggest that local communities, who are key actors in participatory monitoring of coastal and marine resources, face many challenges associated with adapting and applying the said frameworks of indicators and monitoring plans. These indicators tend to be scientifically abstracted and methodologically reified; given prevailing contextual and socio‐cultural realities amongst them. The research project addresses the following key research question: How can processes of abstraction, conceptualisation, and representation of TEK contribute to the development of coastal management indicators that are less reified, more contextually and culturally congruent, and which may potentially be used by resource users in the wider social learning process of detecting trends, threats, changes and conditions of mangrove and fisheries resources? In response to the contextual problem and the research question, the study employs processes of abstraction and experiential learning techniques to unlock knowledge that local communities have, as an input for underlabouring existing scientific indicators on the Eastern coast of Tanzania. The research is constituted as critical realist case study research, involving two communities on the eastern coast of Tanzania, namely the Moa and the Boma communities (in Mkinga coastal district). Overall, the study involved 37 participants in a series of interviews, focus group discussions, and experiential learning processes using visualised data, and an experiential learning intervention workshop, and follow‐ups over a period of 3 years. The study worked with mangroves and fisheries to provide focus to the case study research and to allow for in‐depth engagement with the assumptions and processes associated with indicators development and use. Through the above mentioned data generation processes, critical realist analysis, and experiential learning processes involving abstraction and representation of traditional ecological knowledge held by mangrove restorers and fishers in the study areas, the study uncovers possible challenges of adapting and applying scientific indicators in participatory monitoring of a mangrove ecosystem. Using ampliative modes of inference for data analysis (induction, abduction and retroduction) and a critical realist scientific explanatory framework known as DRRREI(C) (Resolution, Re‐description, Retrodiction, Elimination, Identification, & Correction) the study suggests a new approach that may lead to the development of a framework of indicators that are less reified, more congruent to users (coastal communities), and likely to attract a wider context‐based social learning which favours epistemological access between scientific institutions (universities inclusive), and local communities. It attempts to establish an interface between knowledge that scientific institutions produce and the potential knowledge that exists in local contexts (traditional ecological knowledge), and seeks to widen and improve knowledge sharing and experiential learning practices that may potentially benefit coastal and marine resources in the study area. As mentioned above, the knowledge and abstraction processes related to the indicators development focussed on the mangrove ecosystem and associated fisheries, as engaged in the two participating communities in the eastern coast of Tanzania. The specific findings are therefore limited by the case boundaries, but the methodological process could be replicated and used elsewhere. The study’s contributions are theoretical and methodological, but also social and practice‐centred. The study brings into view the need to consider the contextual relevance of adapted knowledge, the capacity or ability of beneficiaries to adapt and apply scientific models, frameworks or tools, and the potential of local knowledge as an input for enhancing or improving monitoring of mangroves and mangrove‐based fisheries. Finally, the study comes up with a framework of indicators which is regarded by the coastal communities involved in the study as being less reified, more contextually and culturally congruent, and which may potentially be used in detecting environmental trends, threats, changes and conditions of mangrove and fisheries resources, and attract wider social learning processes.
- Full Text:
- Date Issued: 2014
- Authors: Sabai, Daniel
- Date: 2014
- Subjects: Traditional ecological knowledge , Environmental education -- Tanzania , Environmental education -- Study and teaching -- Tanzania , Coastal zone management -- Tanzania , Social learning -- Tanzania , Experiential learning -- Tanzania , Mangrove conservation -- Tanzania , Fishery management -- Tanzania
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1979 , http://hdl.handle.net/10962/d1013060
- Description: This study addresses a core problem that was uncovered in records from coastal management monitoring initiatives on the eastern coast of Tanzania associated with the application and use of coastal monitoring indicators developed by external development partners for the coastal zone. These records suggest that local communities, who are key actors in participatory monitoring of coastal and marine resources, face many challenges associated with adapting and applying the said frameworks of indicators and monitoring plans. These indicators tend to be scientifically abstracted and methodologically reified; given prevailing contextual and socio‐cultural realities amongst them. The research project addresses the following key research question: How can processes of abstraction, conceptualisation, and representation of TEK contribute to the development of coastal management indicators that are less reified, more contextually and culturally congruent, and which may potentially be used by resource users in the wider social learning process of detecting trends, threats, changes and conditions of mangrove and fisheries resources? In response to the contextual problem and the research question, the study employs processes of abstraction and experiential learning techniques to unlock knowledge that local communities have, as an input for underlabouring existing scientific indicators on the Eastern coast of Tanzania. The research is constituted as critical realist case study research, involving two communities on the eastern coast of Tanzania, namely the Moa and the Boma communities (in Mkinga coastal district). Overall, the study involved 37 participants in a series of interviews, focus group discussions, and experiential learning processes using visualised data, and an experiential learning intervention workshop, and follow‐ups over a period of 3 years. The study worked with mangroves and fisheries to provide focus to the case study research and to allow for in‐depth engagement with the assumptions and processes associated with indicators development and use. Through the above mentioned data generation processes, critical realist analysis, and experiential learning processes involving abstraction and representation of traditional ecological knowledge held by mangrove restorers and fishers in the study areas, the study uncovers possible challenges of adapting and applying scientific indicators in participatory monitoring of a mangrove ecosystem. Using ampliative modes of inference for data analysis (induction, abduction and retroduction) and a critical realist scientific explanatory framework known as DRRREI(C) (Resolution, Re‐description, Retrodiction, Elimination, Identification, & Correction) the study suggests a new approach that may lead to the development of a framework of indicators that are less reified, more congruent to users (coastal communities), and likely to attract a wider context‐based social learning which favours epistemological access between scientific institutions (universities inclusive), and local communities. It attempts to establish an interface between knowledge that scientific institutions produce and the potential knowledge that exists in local contexts (traditional ecological knowledge), and seeks to widen and improve knowledge sharing and experiential learning practices that may potentially benefit coastal and marine resources in the study area. As mentioned above, the knowledge and abstraction processes related to the indicators development focussed on the mangrove ecosystem and associated fisheries, as engaged in the two participating communities in the eastern coast of Tanzania. The specific findings are therefore limited by the case boundaries, but the methodological process could be replicated and used elsewhere. The study’s contributions are theoretical and methodological, but also social and practice‐centred. The study brings into view the need to consider the contextual relevance of adapted knowledge, the capacity or ability of beneficiaries to adapt and apply scientific models, frameworks or tools, and the potential of local knowledge as an input for enhancing or improving monitoring of mangroves and mangrove‐based fisheries. Finally, the study comes up with a framework of indicators which is regarded by the coastal communities involved in the study as being less reified, more contextually and culturally congruent, and which may potentially be used in detecting environmental trends, threats, changes and conditions of mangrove and fisheries resources, and attract wider social learning processes.
- Full Text:
- Date Issued: 2014
Challenging desire : performing whiteness in post-apartheid South Africa
- Authors: Smit, Sonja
- Date: 2014
- Subjects: Performance art -- South Africa , Bailey, Brett, 1967- , Cohen, Steven, 1962- , Antwoord (Musical group) , MacGarry, Michael , Eurocentrism -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2164 , http://hdl.handle.net/10962/d1016358
- Description: The central argument of this thesis asserts that in the process of challenging dominant subject positions, such as whiteness, performance creates the possibilities for new or alternative arrangements of desire. It examines how the creative process of desire is forestalled (reified) by habitual representations of whiteness as a privileged position, and proposes that performance can be a valid form of resistance to static conceptions of race and subjectivity. The discussion takes into account how the privilege of whiteness finds representation through forms of neo-liberalism and neo-colonialism in the post apartheid context. The analysis focuses on the work of white South African artists whose work offers a critique from within the privileged “centre” of whiteness. The research is situated within the inter-disciplinary field of performance studies entailing a reading and application of critical texts to the analysis. Alongside this qualitative methodology surfaces a subjective dialogue with the information presented on whiteness. Part Two includes an analysis of Steven Cohen’s The Cradle of Humankind (2011), Brett Bailey’s Exhibit A (2011) and Michael MacGarry’s LHR-JNB (2010). Each section examines the way in which the respective works engage in a questioning of whiteness through performance. Part Three investigates South African rap-rave duo, Die Antwoord and how their appropriation of Zef interrogates desires for an essential authenticity. Part Four focuses on my own performance practice and the proposed value of engaging with a form of practice-led research. This is particularly relevant in relation to critical race studies that require a level of self-reflexivity from the researcher. It presents an analysis of the work entitled Villain (2012) as a disturbance of theatrical desire through a process of ‘becoming’. This notion of meaning and identity as ‘becoming’ is argued as a strategy to challenge prevailing modes of perception which can possibly restore the production of desire to the viewer. The thesis concludes with the notion that performance can offer a mode of immanent ethics which is significant in creating both vulnerable and critical forms of whiteness.
- Full Text:
- Date Issued: 2014
- Authors: Smit, Sonja
- Date: 2014
- Subjects: Performance art -- South Africa , Bailey, Brett, 1967- , Cohen, Steven, 1962- , Antwoord (Musical group) , MacGarry, Michael , Eurocentrism -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2164 , http://hdl.handle.net/10962/d1016358
- Description: The central argument of this thesis asserts that in the process of challenging dominant subject positions, such as whiteness, performance creates the possibilities for new or alternative arrangements of desire. It examines how the creative process of desire is forestalled (reified) by habitual representations of whiteness as a privileged position, and proposes that performance can be a valid form of resistance to static conceptions of race and subjectivity. The discussion takes into account how the privilege of whiteness finds representation through forms of neo-liberalism and neo-colonialism in the post apartheid context. The analysis focuses on the work of white South African artists whose work offers a critique from within the privileged “centre” of whiteness. The research is situated within the inter-disciplinary field of performance studies entailing a reading and application of critical texts to the analysis. Alongside this qualitative methodology surfaces a subjective dialogue with the information presented on whiteness. Part Two includes an analysis of Steven Cohen’s The Cradle of Humankind (2011), Brett Bailey’s Exhibit A (2011) and Michael MacGarry’s LHR-JNB (2010). Each section examines the way in which the respective works engage in a questioning of whiteness through performance. Part Three investigates South African rap-rave duo, Die Antwoord and how their appropriation of Zef interrogates desires for an essential authenticity. Part Four focuses on my own performance practice and the proposed value of engaging with a form of practice-led research. This is particularly relevant in relation to critical race studies that require a level of self-reflexivity from the researcher. It presents an analysis of the work entitled Villain (2012) as a disturbance of theatrical desire through a process of ‘becoming’. This notion of meaning and identity as ‘becoming’ is argued as a strategy to challenge prevailing modes of perception which can possibly restore the production of desire to the viewer. The thesis concludes with the notion that performance can offer a mode of immanent ethics which is significant in creating both vulnerable and critical forms of whiteness.
- Full Text:
- Date Issued: 2014
Direct and indirect effects of zooplanktivorous predators on the estuarine plankton community
- Authors: Wasserman, Ryan John
- Date: 2014
- Subjects: Zooplankton -- Effect of predation on , Predation (Biology) , Zooplankton -- Predators of , Copepoda
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5870 , http://hdl.handle.net/10962/d1012938
- Description: Although predation has been identified as a potentially important driver in terrestrial and freshwater ecosystems, estuarine planktonic research has focused largely on the so-called "bottom-up" drivers of community assemblages. As such, this thesis focuses on the direct and indirect effects of zooplanktivorous predators on the planktonic community in an estuarine environment. By using a suite of in situ mesocosm experiments, a number of hypotheses, pertaining to the major research themes associated with predator-prey interactions, are tested. These themes included trophic cascading, risk effects associated with predation events and the importance of predator diversity in maintaining prey communities. The first experiment assessed the significance of apex predation pressure for the planktonic community through trophic cascades. Various treatments using in situ mesocosms were established in a closed oligotrophic estuary to highlight the importance of predation in stabilising estuarine plankton abundances. Through either the removal (filtration) or addition of certain planktonic groups, varied trophic scenarios were established. The experimental treatment containing apex zooplanktivores had consequences for multiple trophic levels, exerting a stabilising pressure throughout the food web (Chapter 3). Furthermore, pyrosequencing of filtered water samples revealed that when compared to the remaining treatments, the treatment containing stable apex predatory pressure experienced limited temporal deviation-from-initial in bacterial community structure (Chapter 4). These findings are consistent with trophic cascade theory whereby predators mediate interactions at multiple lower trophic levels with consequent repercussions for diversity. To assess the non-consumptive effects of predators on prey, two experiments were conducted. Firstly, using egg numbers per clutch as a measure of potential reproductive output, the non-lethal effects of predatory pressure on reproductive success in a key planktonic copepod was investigated. In this study, the average clutch size of fecund female copepods was found to be consistently lower in the presence of predators when compared to females not exposed to predation threat (Chapter 5). The second study assessed the effects of conspecific chemical alarm cues associated with predation, on population dynamics of a copepod species. This study revealed that the copepods appear to detect the presence of chemical alarm cues associated with predation events, with repercussions for population demographics over time. Furthermore, it showed that in the absence of actual predation, copepod prey responses to alarm cues were adjusted over time, consistent with the threat sensitive predator avoidance hypothesis (Chapter 6). The final data chapter dealt with predator diversity and its implications for zooplankton community structure. By experimentally monitoring the effects of two alternate model predators on the metazoan community over time, dissimilarities in community level control emerged. Alternate key prey populations were regulated by the different model predators, highlighting the importance of predator and prey behaviour in mediating predator-prey interactions (Chapter 7). These results highlight the potential importance of predators in maintaining community dynamics in estuarine planktonic communities under certain conditions. This study represents some of the first work to address these various aspects of predator-prey dynamics within the context of planktonic estuarine ecology.
- Full Text:
- Date Issued: 2014
- Authors: Wasserman, Ryan John
- Date: 2014
- Subjects: Zooplankton -- Effect of predation on , Predation (Biology) , Zooplankton -- Predators of , Copepoda
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5870 , http://hdl.handle.net/10962/d1012938
- Description: Although predation has been identified as a potentially important driver in terrestrial and freshwater ecosystems, estuarine planktonic research has focused largely on the so-called "bottom-up" drivers of community assemblages. As such, this thesis focuses on the direct and indirect effects of zooplanktivorous predators on the planktonic community in an estuarine environment. By using a suite of in situ mesocosm experiments, a number of hypotheses, pertaining to the major research themes associated with predator-prey interactions, are tested. These themes included trophic cascading, risk effects associated with predation events and the importance of predator diversity in maintaining prey communities. The first experiment assessed the significance of apex predation pressure for the planktonic community through trophic cascades. Various treatments using in situ mesocosms were established in a closed oligotrophic estuary to highlight the importance of predation in stabilising estuarine plankton abundances. Through either the removal (filtration) or addition of certain planktonic groups, varied trophic scenarios were established. The experimental treatment containing apex zooplanktivores had consequences for multiple trophic levels, exerting a stabilising pressure throughout the food web (Chapter 3). Furthermore, pyrosequencing of filtered water samples revealed that when compared to the remaining treatments, the treatment containing stable apex predatory pressure experienced limited temporal deviation-from-initial in bacterial community structure (Chapter 4). These findings are consistent with trophic cascade theory whereby predators mediate interactions at multiple lower trophic levels with consequent repercussions for diversity. To assess the non-consumptive effects of predators on prey, two experiments were conducted. Firstly, using egg numbers per clutch as a measure of potential reproductive output, the non-lethal effects of predatory pressure on reproductive success in a key planktonic copepod was investigated. In this study, the average clutch size of fecund female copepods was found to be consistently lower in the presence of predators when compared to females not exposed to predation threat (Chapter 5). The second study assessed the effects of conspecific chemical alarm cues associated with predation, on population dynamics of a copepod species. This study revealed that the copepods appear to detect the presence of chemical alarm cues associated with predation events, with repercussions for population demographics over time. Furthermore, it showed that in the absence of actual predation, copepod prey responses to alarm cues were adjusted over time, consistent with the threat sensitive predator avoidance hypothesis (Chapter 6). The final data chapter dealt with predator diversity and its implications for zooplankton community structure. By experimentally monitoring the effects of two alternate model predators on the metazoan community over time, dissimilarities in community level control emerged. Alternate key prey populations were regulated by the different model predators, highlighting the importance of predator and prey behaviour in mediating predator-prey interactions (Chapter 7). These results highlight the potential importance of predators in maintaining community dynamics in estuarine planktonic communities under certain conditions. This study represents some of the first work to address these various aspects of predator-prey dynamics within the context of planktonic estuarine ecology.
- Full Text:
- Date Issued: 2014
A context-aware model to improve usability of information presented on mobile devices
- Authors: Ntawanga, Felix Fred
- Date: 2014
- Subjects: Context-aware computing , Online information services
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10495 , http://hdl.handle.net/10948/d1020768
- Description: Online information access on mobile devices is increasing as a result of the growth in the use of Internet-enabled handheld (or pocket-size) devices. The combined influence of recent enabling technologies such as Web 2.0, mobile app stores and improved wireless networks have driven the increase in online applications that allow users to access various types of information on mobile devices regardless of time and location. Examples of such applications (usually shortened to app) include: social media, such as FacebookTM App and TwitterTM App, banking applications such as (Standard Bank South Africa)TM Mobile Banking App and First National Bank (FNB) BankingTM App, and news application such as news 24TM App and BBCTM News App. Online businesses involved in buying, selling and business transaction processing activities via the Internet have exploited the opportunity to extend electronic commerce (e-commerce) initiatives into mobile commerce (m-commerce). Online businesses that interact with end user customers implement business to consumer (B2C) m-commerce applications that enable customers to access and browse product catalogue information on mobile devices, anytime, anywhere. Customers accessing electronic product catalogue information on a mobile device face a number of challenges such as a long list of products presented on a small screen and a longer information download time. These challenges mainly originate from the limiting and dynamic nature of the mobile apps operating environment, for example, dynamic location, bandwidth fluctuations and, diverse and limited device features, collectively referred to as context. The goal of this research was to design and implement a context-aware model that can be incorporated into an m-commerce application in order to improve the presentation of product catalogue information on m-commerce storefronts. The motivation for selecting product catalogue is prompted by literature which indicates that improved presentation of information in m-commerce (and e-commerce) applications has a positive impact on usability of the websites. Usable m-commerce (and e-commerce) websites improve efficiency in consumer behaviour that impacts sales, profits and business growth. The context-aware model aimed at collecting context information within the user environment and utilising it to determine optimal retrieval and presentation of product catalogue in m-commerce. An integrated logical context sensor and Mathematical algorithms were implemented in the context-aware model. The integrated logical context sensor was responsible for the collection of different types of predetermined context information such as device specification or capabilities, connection bandwidth, location and time of the day as well as the user profile. The algorithms transformed the collected context information into usable formats and enabled optimal retrieval and presentation of product catalogue data on a specific mobile device. Open-source implementation tools were utilised to implement components of the model including: HTML5, PhP, JavaScript and MySQL database. The context-aware model was incorporated into an existing m-commerce application. Two user evaluation studies were conducted during the course of the research. The first evaluation was to evaluate the accuracy of information collected by the context sensor component of the model. This survey was conducted with a sample of 30 users from different countries across the world. In-between the context sensor and main evaluation surveys, a pilot study was conducted with a sample of 19 users with great experience in mobile application development and use from SAP Next Business and Technology, Africa. Finally an overall user evaluation study was conducted with a sample of 30 users from a remote area called Kgautswane in Limpopo Province, South Africa. The results obtained indicate that the context-aware model was able to determine accurate context information in real-time and effectively determine how much product information should be retrieved and how the information should be presented on a mobile device interface. Two main contributions emerged from the research, first the research contributed to the field of mobile Human Computer Interaction. During the research, techniques of evaluating and improving usability of mobile applications were demonstrated. Secondly, the research made a significant contribution to the upcoming field of context-aware computing. The research brought clarity with regard to context-aware computing which is lacking in existing, current research despite the field’s proven impact of improving usability of applications. Researchers can utilise contributions made in this research to develop further techniques and usable context-aware solutions.
- Full Text:
- Date Issued: 2014
- Authors: Ntawanga, Felix Fred
- Date: 2014
- Subjects: Context-aware computing , Online information services
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10495 , http://hdl.handle.net/10948/d1020768
- Description: Online information access on mobile devices is increasing as a result of the growth in the use of Internet-enabled handheld (or pocket-size) devices. The combined influence of recent enabling technologies such as Web 2.0, mobile app stores and improved wireless networks have driven the increase in online applications that allow users to access various types of information on mobile devices regardless of time and location. Examples of such applications (usually shortened to app) include: social media, such as FacebookTM App and TwitterTM App, banking applications such as (Standard Bank South Africa)TM Mobile Banking App and First National Bank (FNB) BankingTM App, and news application such as news 24TM App and BBCTM News App. Online businesses involved in buying, selling and business transaction processing activities via the Internet have exploited the opportunity to extend electronic commerce (e-commerce) initiatives into mobile commerce (m-commerce). Online businesses that interact with end user customers implement business to consumer (B2C) m-commerce applications that enable customers to access and browse product catalogue information on mobile devices, anytime, anywhere. Customers accessing electronic product catalogue information on a mobile device face a number of challenges such as a long list of products presented on a small screen and a longer information download time. These challenges mainly originate from the limiting and dynamic nature of the mobile apps operating environment, for example, dynamic location, bandwidth fluctuations and, diverse and limited device features, collectively referred to as context. The goal of this research was to design and implement a context-aware model that can be incorporated into an m-commerce application in order to improve the presentation of product catalogue information on m-commerce storefronts. The motivation for selecting product catalogue is prompted by literature which indicates that improved presentation of information in m-commerce (and e-commerce) applications has a positive impact on usability of the websites. Usable m-commerce (and e-commerce) websites improve efficiency in consumer behaviour that impacts sales, profits and business growth. The context-aware model aimed at collecting context information within the user environment and utilising it to determine optimal retrieval and presentation of product catalogue in m-commerce. An integrated logical context sensor and Mathematical algorithms were implemented in the context-aware model. The integrated logical context sensor was responsible for the collection of different types of predetermined context information such as device specification or capabilities, connection bandwidth, location and time of the day as well as the user profile. The algorithms transformed the collected context information into usable formats and enabled optimal retrieval and presentation of product catalogue data on a specific mobile device. Open-source implementation tools were utilised to implement components of the model including: HTML5, PhP, JavaScript and MySQL database. The context-aware model was incorporated into an existing m-commerce application. Two user evaluation studies were conducted during the course of the research. The first evaluation was to evaluate the accuracy of information collected by the context sensor component of the model. This survey was conducted with a sample of 30 users from different countries across the world. In-between the context sensor and main evaluation surveys, a pilot study was conducted with a sample of 19 users with great experience in mobile application development and use from SAP Next Business and Technology, Africa. Finally an overall user evaluation study was conducted with a sample of 30 users from a remote area called Kgautswane in Limpopo Province, South Africa. The results obtained indicate that the context-aware model was able to determine accurate context information in real-time and effectively determine how much product information should be retrieved and how the information should be presented on a mobile device interface. Two main contributions emerged from the research, first the research contributed to the field of mobile Human Computer Interaction. During the research, techniques of evaluating and improving usability of mobile applications were demonstrated. Secondly, the research made a significant contribution to the upcoming field of context-aware computing. The research brought clarity with regard to context-aware computing which is lacking in existing, current research despite the field’s proven impact of improving usability of applications. Researchers can utilise contributions made in this research to develop further techniques and usable context-aware solutions.
- Full Text:
- Date Issued: 2014
Trophic relationships of hake (Merluccius capensis Castelnau, 1851 and M. paradoxus Franca 1960) from the Northern Benguela current ecosystem (Namibia) : inferences from stable isotopes and fatty acids
- Authors: Iitembu, Johannes Angala
- Date: 2014
- Subjects: Hake -- Benguela Current , Merlucciidae -- Benguela Current , Multitrophic interactions (Ecology) , Food chains (Ecology) , Biotic communities -- Benguela Current , Merlucciidae -- Food , Fishery management -- Namibia , Stable isotopes , Fatty acids
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5944 , http://hdl.handle.net/10962/d1020296
- Description: Two species of hake (Merluccius capensis and Merluccius paradoxus) account for most of Namibia’s fisheries catch, and they are important secondary consumers in the Benguela Current ecosystem. Inferences on their trophic relationships have been based mainly on stomach content analyses. However, such data are limited temporally because they represent only snapshots of recent feeding, and are quantitatively biased because of variation in the digestion rates of different prey. The principal aim of the thesis was to understand the trophic relationships of two hake species relative to each other, their known prey and top predators (demersal sharks) in the northern Benguela Current ecosystem (Namibia), using time-integrating trophic biomarkers. By using stable isotope (carbon and nitrogen) and fatty acid signatures of their muscle tissues, my overall objectives were to produce new knowledge about 1) hake ontogenic trophic relationships, 2) the contributions of different prey to hake diets, 3) hake dietary differences, and 4) some aspects of hake’s trophic relationships with demersal sharks. Tissues of hake (n=358), their potential prey (n=455), and demersal sharks (n=42) were collected between 2008 and 2012 during demersal bottom trawl surveys off Namibia, for stable isotope and fatty acid analyses. And more...
- Full Text:
- Date Issued: 2014
- Authors: Iitembu, Johannes Angala
- Date: 2014
- Subjects: Hake -- Benguela Current , Merlucciidae -- Benguela Current , Multitrophic interactions (Ecology) , Food chains (Ecology) , Biotic communities -- Benguela Current , Merlucciidae -- Food , Fishery management -- Namibia , Stable isotopes , Fatty acids
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5944 , http://hdl.handle.net/10962/d1020296
- Description: Two species of hake (Merluccius capensis and Merluccius paradoxus) account for most of Namibia’s fisheries catch, and they are important secondary consumers in the Benguela Current ecosystem. Inferences on their trophic relationships have been based mainly on stomach content analyses. However, such data are limited temporally because they represent only snapshots of recent feeding, and are quantitatively biased because of variation in the digestion rates of different prey. The principal aim of the thesis was to understand the trophic relationships of two hake species relative to each other, their known prey and top predators (demersal sharks) in the northern Benguela Current ecosystem (Namibia), using time-integrating trophic biomarkers. By using stable isotope (carbon and nitrogen) and fatty acid signatures of their muscle tissues, my overall objectives were to produce new knowledge about 1) hake ontogenic trophic relationships, 2) the contributions of different prey to hake diets, 3) hake dietary differences, and 4) some aspects of hake’s trophic relationships with demersal sharks. Tissues of hake (n=358), their potential prey (n=455), and demersal sharks (n=42) were collected between 2008 and 2012 during demersal bottom trawl surveys off Namibia, for stable isotope and fatty acid analyses. And more...
- Full Text:
- Date Issued: 2014
Nonlinear optical studies of metallophtalocyanines and hemiporphyrazines in solution
- Authors: Britton, Jonathan
- Date: 2014
- Subjects: Phthalocyanines Photochemistry Nanoparticles Nanostructured materials Polymers Quantum dots
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4464 , http://hdl.handle.net/10962/d1011608
- Description: This thesis presents the study of the effects of CdTe-TGA quantum dots (QDs) on optical limiting ability of different phthalocyanine (Pc) complexes (5-12) containing Zn, Ga, In central metals and substituted with benzyloxyphenoxy, phenoxy, tertbutylphenoxy and amino groups in solution and in poly (methyl methacrylate) (PMMA) films. The optical limiting parameters of Pcs were higher for tertbutylphenoxy when compared to benzyloxyphenoxy and phenoxy substituents, in DMSO. Non-peripheral substitution decreased the optical limiting parameters. Third-order susceptibility (Im[χ⁽³⁾]/α) values of Pcs in the absence and presence of CdTe QDs were in the 10⁻¹² to 10⁻¹° esu cm range. Hyperpolarizabilities (γ) ranged from 10⁻³¹ to 10⁻²⁹ esu L for Pc alone or in mixture with QDs. The effect on the optical limiting abilities of twelve embedded phthalocyanines containing In, Ga, Zn and Al as central metals in polymer thin films was also examined. The effect of forming a covalent link zinc tetraamino phthalocyanine (12) with poly (methyl acrylic acid) (PMAA) and Zn (13) and OHAl (14) octacarboxy phthalocyanines to polyethylenimine (PEI) was also studied. The hyperpolarizability of the twelve phthalocyanines in polymer was found to be in the range of 10⁻²⁶ to 10⁻²⁴ esu.L. This is significantly higher than the hyperpolarizabilities of these phthalocyanines in solution. Non-linear optical (NLO) parameters were determined for phthalocyanine complexes containing In, Ga and Zn as central metals when embedded in PMMA polymer in the presence of quantum dots (QDs). The QDs mainly employed were CdTe-TGA (TGA = thioglylcolic acid). Triplet lifetimes increased as k (excited state (σex) to ground state (σg) absorption cross section ratio) values decreased with the addition of the CdTe-TGA to the phthalocyanines. The saturation energy density (Fsat) values were smaller in the films when compared to the solutions. Complex 7 tetrasubstituted with tert-butylphenoxy groups at non-peripheral positions was also studied in the presence of CdS-TGA, CdSe-TGA, fullerenes and single walled carbon nanotubes. There is a general improvement in optical limiting ability of Pc complexes in the presence of nanomaterials (NMs). Degradation studies seem to indicate that placing a phthalocyanine within a polymer thin film may protect it slightly from photo- and thermal degradation. 3(4), 15(16)-Bis-(4 -tert-butyl-phenoxy)-10, 22-diaminohemiporphyrazinato chloroindium hemiporphyrazine was synthesized from 1, 3, 5-triaminobenzene and 4-tert-butyl-phenoxyisoindoline. The structure of the complex was confirmed using mass, nuclear magnetic resonance and infrared spectroscopies. The nonlinear parameters of the compound was also analyzed in dimethylformamide and found to be significantly greater than previously analyzed phthalocyanines.
- Full Text:
- Date Issued: 2014
- Authors: Britton, Jonathan
- Date: 2014
- Subjects: Phthalocyanines Photochemistry Nanoparticles Nanostructured materials Polymers Quantum dots
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4464 , http://hdl.handle.net/10962/d1011608
- Description: This thesis presents the study of the effects of CdTe-TGA quantum dots (QDs) on optical limiting ability of different phthalocyanine (Pc) complexes (5-12) containing Zn, Ga, In central metals and substituted with benzyloxyphenoxy, phenoxy, tertbutylphenoxy and amino groups in solution and in poly (methyl methacrylate) (PMMA) films. The optical limiting parameters of Pcs were higher for tertbutylphenoxy when compared to benzyloxyphenoxy and phenoxy substituents, in DMSO. Non-peripheral substitution decreased the optical limiting parameters. Third-order susceptibility (Im[χ⁽³⁾]/α) values of Pcs in the absence and presence of CdTe QDs were in the 10⁻¹² to 10⁻¹° esu cm range. Hyperpolarizabilities (γ) ranged from 10⁻³¹ to 10⁻²⁹ esu L for Pc alone or in mixture with QDs. The effect on the optical limiting abilities of twelve embedded phthalocyanines containing In, Ga, Zn and Al as central metals in polymer thin films was also examined. The effect of forming a covalent link zinc tetraamino phthalocyanine (12) with poly (methyl acrylic acid) (PMAA) and Zn (13) and OHAl (14) octacarboxy phthalocyanines to polyethylenimine (PEI) was also studied. The hyperpolarizability of the twelve phthalocyanines in polymer was found to be in the range of 10⁻²⁶ to 10⁻²⁴ esu.L. This is significantly higher than the hyperpolarizabilities of these phthalocyanines in solution. Non-linear optical (NLO) parameters were determined for phthalocyanine complexes containing In, Ga and Zn as central metals when embedded in PMMA polymer in the presence of quantum dots (QDs). The QDs mainly employed were CdTe-TGA (TGA = thioglylcolic acid). Triplet lifetimes increased as k (excited state (σex) to ground state (σg) absorption cross section ratio) values decreased with the addition of the CdTe-TGA to the phthalocyanines. The saturation energy density (Fsat) values were smaller in the films when compared to the solutions. Complex 7 tetrasubstituted with tert-butylphenoxy groups at non-peripheral positions was also studied in the presence of CdS-TGA, CdSe-TGA, fullerenes and single walled carbon nanotubes. There is a general improvement in optical limiting ability of Pc complexes in the presence of nanomaterials (NMs). Degradation studies seem to indicate that placing a phthalocyanine within a polymer thin film may protect it slightly from photo- and thermal degradation. 3(4), 15(16)-Bis-(4 -tert-butyl-phenoxy)-10, 22-diaminohemiporphyrazinato chloroindium hemiporphyrazine was synthesized from 1, 3, 5-triaminobenzene and 4-tert-butyl-phenoxyisoindoline. The structure of the complex was confirmed using mass, nuclear magnetic resonance and infrared spectroscopies. The nonlinear parameters of the compound was also analyzed in dimethylformamide and found to be significantly greater than previously analyzed phthalocyanines.
- Full Text:
- Date Issued: 2014
An investigation into the development of knowledge and strategies for the teaching of visual literacy in under-resourced Eastern Cape schools
- Authors: Mbelani, Madeyandile
- Date: 2014
- Subjects: Uncatalogued
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/64401 , vital:28540
- Description: This thesis reports on a multiple case study PhD project that aimed to investigate meaningful and critical development of knowledge and strategies to teach visual literacy, a component of English First Additional Language (FAL) in six under-resourced schools of the Eastern Cape of South Africa. The study begins by locating visual literacy within a broad framework of literacy as a social practice, and discusses its importance. Further, it discusses complexities of making sense of and teaching visual literacy, especially for the majority of in-service teachers who experienced visual literacy neither as learners nor as teacher trainees. The gap between the curriculum and teachers’ classroom practices is what triggered this study to adopt a transformative paradigm. The main research question is, “How can teacher professional development in English Language Teaching advance in-service teachers’ knowledge of and strategies for meaningful and critical teaching and learning of visual literacy?” To respond to this question, I drew on cultural historical activity theory (CHAT) and critical realism (CR) to design four phases of this study that incorporated the seven stages of an expansive learning cycle. These phases focussed on exploring and expanding teachers’ sense making and teaching of visual literacy. I collected data through interviews, document analysis, videoed lessons and change laboratory (CL) workshops. I designed a data analysis tool that brought together CHAT, CR, multimodal social semiotics, critical discourse analysis and pedagogical discourse to make sense of the data. Through a process of reflexivity, the study illuminated layers of factors that constrained meaningful and critical teaching of visual literacy in the empirical, the actual and the real domains of reality. These factors include teachers’ unconscious reproduction of discourses of domination, their intolerance of diverse cultural discourses, resistance to curriculum change, and the fact that they are comfortable with the status quo. I brought these factors to CL workshops for expansive learning. The study contributes in-depth insight into English FAL in-service teacher development in the area of visual literacy. By locating the study within meaning making and teaching of visual literacy, it was possible to interrogate access, diversity, domination and design in teachers’ classroom practices. As a result of this study participants were made aware of the extent to which these factors enabled or hindered meaningful and critical teaching. Participants repositioned themselves as subjects of the activity system, thereby mobilising their agency to take control of the structures and cultures that condition their teaching.
- Full Text:
- Date Issued: 2014
- Authors: Mbelani, Madeyandile
- Date: 2014
- Subjects: Uncatalogued
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/64401 , vital:28540
- Description: This thesis reports on a multiple case study PhD project that aimed to investigate meaningful and critical development of knowledge and strategies to teach visual literacy, a component of English First Additional Language (FAL) in six under-resourced schools of the Eastern Cape of South Africa. The study begins by locating visual literacy within a broad framework of literacy as a social practice, and discusses its importance. Further, it discusses complexities of making sense of and teaching visual literacy, especially for the majority of in-service teachers who experienced visual literacy neither as learners nor as teacher trainees. The gap between the curriculum and teachers’ classroom practices is what triggered this study to adopt a transformative paradigm. The main research question is, “How can teacher professional development in English Language Teaching advance in-service teachers’ knowledge of and strategies for meaningful and critical teaching and learning of visual literacy?” To respond to this question, I drew on cultural historical activity theory (CHAT) and critical realism (CR) to design four phases of this study that incorporated the seven stages of an expansive learning cycle. These phases focussed on exploring and expanding teachers’ sense making and teaching of visual literacy. I collected data through interviews, document analysis, videoed lessons and change laboratory (CL) workshops. I designed a data analysis tool that brought together CHAT, CR, multimodal social semiotics, critical discourse analysis and pedagogical discourse to make sense of the data. Through a process of reflexivity, the study illuminated layers of factors that constrained meaningful and critical teaching of visual literacy in the empirical, the actual and the real domains of reality. These factors include teachers’ unconscious reproduction of discourses of domination, their intolerance of diverse cultural discourses, resistance to curriculum change, and the fact that they are comfortable with the status quo. I brought these factors to CL workshops for expansive learning. The study contributes in-depth insight into English FAL in-service teacher development in the area of visual literacy. By locating the study within meaning making and teaching of visual literacy, it was possible to interrogate access, diversity, domination and design in teachers’ classroom practices. As a result of this study participants were made aware of the extent to which these factors enabled or hindered meaningful and critical teaching. Participants repositioned themselves as subjects of the activity system, thereby mobilising their agency to take control of the structures and cultures that condition their teaching.
- Full Text:
- Date Issued: 2014
Modelling the hydrological responses to changes in land use and cover in the Malaba River Catchment, Eastern Uganda
- Authors: Barasa, Bernard
- Date: 2014
- Subjects: Hydrologic models -- Uganda , Runoff -- Uganda
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10670 , http://hdl.handle.net/10948/d1020153
- Description: Hydrological responses vary from one catchment to another, depending on the nature of land use and cover changes. Modelling the hydrological responses to changes in land use and cover at different catchment spatial scales was the major focus of this study. This study assessed the hydrological responses attributed to changes in land use and extreme weather events resulting into increased sediment loading/concentration, rainfall-runoff generation/volume, streamflow fluctuation and modification of the river channel in the Malaba River Catchment, Eastern Uganda. The hydrological responses were assessed using hydrological models (IHACRES, SCS CN, and SHETRAN) to examine the effect of land use on soil physio-chemical properties susceptibility to rainfall-runoff generation and volume, frequency and severity of extreme weather events, changes in streamflow variations, sediment loading/concentration and river channel morphology. The preliminary study results showed that the frequency of extreme weather events reduced from 4-10 to 1-3 years over the catchment. The performance of the IHACRES model with a Nash-Sutcliffe Efficiency (NSE) of 0.89 showed that streamflow comparatively corresponded with the results obtained the drought indices in predicting the recorded events of severe drought (2005) and flood (1997). Changes in land use and cover types showed that the highest change in the gain of land was experienced from the agricultural land use (36.7 percent), and tropical forest (regeneration) (2.2 percent). The biggest losses in land were experienced in the wetlands (24.6 percent) and bushland and thickets (15.3 percent) land cover types. The SHETRAN model calibrated period had a NSE of 0.78 and 0.81 in the validation period showed satisfactory fits between the measured and simulated streamflow. The agricultural land use (crop growing) had a higher influence on the rainfall-runoff generation and increase in the streamflow than the tropical forest, and bushland cover types in the simulated period. Similarly, the curve number model estimated a comparatively higher surface rainfall-runoff volume generated from the agricultural land use (crop growing) (71,740 m3) than in the bushlands and thickets (42,872 m3) from a rainstorm followed by the tropical forest cover type. This was also reflected in the lower rates of saturated hydraulic conductivity from the agricultural land use (crop growing). The study also showed that human-induced sediment loading due to gold mining activities contributed a much higher impact on the concentration of suspended sediments and streamflow than sediments from rainfall-runoff from the sampled streams. The main contributor of human-induced sediments to the Malaba River were Nankuke River (130.6kg/annum), followed by Omanyi River (70.6kg/annum), and Nabewo River (66.8kg/annum). Human-induced sediment loading had a profound impact on the streamflow variations both in the dry and wet seasons from the sampled tributaries. Lastly, in regard to the effect of land use and cover types on the river channel morphology, tree plantation (cohesion=12, angle of internal friction=27) and bushland and thickets (cohesion=14, angle of internal friction=22) cover types had the most stable river banks compared to the wetland and agricultural land use and cover types that exhibited higher levels of sediment concentration.
- Full Text:
- Date Issued: 2014
- Authors: Barasa, Bernard
- Date: 2014
- Subjects: Hydrologic models -- Uganda , Runoff -- Uganda
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10670 , http://hdl.handle.net/10948/d1020153
- Description: Hydrological responses vary from one catchment to another, depending on the nature of land use and cover changes. Modelling the hydrological responses to changes in land use and cover at different catchment spatial scales was the major focus of this study. This study assessed the hydrological responses attributed to changes in land use and extreme weather events resulting into increased sediment loading/concentration, rainfall-runoff generation/volume, streamflow fluctuation and modification of the river channel in the Malaba River Catchment, Eastern Uganda. The hydrological responses were assessed using hydrological models (IHACRES, SCS CN, and SHETRAN) to examine the effect of land use on soil physio-chemical properties susceptibility to rainfall-runoff generation and volume, frequency and severity of extreme weather events, changes in streamflow variations, sediment loading/concentration and river channel morphology. The preliminary study results showed that the frequency of extreme weather events reduced from 4-10 to 1-3 years over the catchment. The performance of the IHACRES model with a Nash-Sutcliffe Efficiency (NSE) of 0.89 showed that streamflow comparatively corresponded with the results obtained the drought indices in predicting the recorded events of severe drought (2005) and flood (1997). Changes in land use and cover types showed that the highest change in the gain of land was experienced from the agricultural land use (36.7 percent), and tropical forest (regeneration) (2.2 percent). The biggest losses in land were experienced in the wetlands (24.6 percent) and bushland and thickets (15.3 percent) land cover types. The SHETRAN model calibrated period had a NSE of 0.78 and 0.81 in the validation period showed satisfactory fits between the measured and simulated streamflow. The agricultural land use (crop growing) had a higher influence on the rainfall-runoff generation and increase in the streamflow than the tropical forest, and bushland cover types in the simulated period. Similarly, the curve number model estimated a comparatively higher surface rainfall-runoff volume generated from the agricultural land use (crop growing) (71,740 m3) than in the bushlands and thickets (42,872 m3) from a rainstorm followed by the tropical forest cover type. This was also reflected in the lower rates of saturated hydraulic conductivity from the agricultural land use (crop growing). The study also showed that human-induced sediment loading due to gold mining activities contributed a much higher impact on the concentration of suspended sediments and streamflow than sediments from rainfall-runoff from the sampled streams. The main contributor of human-induced sediments to the Malaba River were Nankuke River (130.6kg/annum), followed by Omanyi River (70.6kg/annum), and Nabewo River (66.8kg/annum). Human-induced sediment loading had a profound impact on the streamflow variations both in the dry and wet seasons from the sampled tributaries. Lastly, in regard to the effect of land use and cover types on the river channel morphology, tree plantation (cohesion=12, angle of internal friction=27) and bushland and thickets (cohesion=14, angle of internal friction=22) cover types had the most stable river banks compared to the wetland and agricultural land use and cover types that exhibited higher levels of sediment concentration.
- Full Text:
- Date Issued: 2014
Customer relationship management in small to medium tourism enterprises (SMTEs) in the Eastern Cape Province
- Authors: Vallabh, Dinesh
- Date: 2014
- Subjects: Customer relations -- Management , Small business -- South Africa -- Eastern Cape , Tourism -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:9322 , http://hdl.handle.net/10948/d1020797
- Description: The role of entrepreneurship in small to medium tourism enterprises is well recognised and acknowledged as a significant contributor to economic development and employment opportunities. Worldwide, small to medium tourism enterprises play a dominant role in the tourism industry. These businesses are often vulnerable to external economic forces and find it increasingly difficult to transform their strategic and operational management to face the challenges placed upon them. This study focuses on small to medium tourism enterprises in the Eastern Cape Province, which is economically the poorest province of South Africa. To ensure the growth and sustainability of small to medium tourism enterprises, owners need to make efficient and effective business decisions regarding the challenges their businesses face. The study examines the factors impacting customer relationship management in the context of small to medium tourism enterprises in the Eastern Cape. Customer relationship management, that is, building relationships with customers, has become of pivotal importance to many organisations as businesses strive to be competitive and profitable. While large organisations practice customer relationship management to enable them to better target profitable customers, improve customer services, enhance customer retention and ultimately improve business performance, small businesses often need assistance in understanding and effecting this complex relationship. The factors that could impact customer relationship management in the organisations are the focus of this study. Three major factors were identified, namely, strategic, operational, and organisational factors. The study furthermore examined the extent to which these factors are present in the tourism and hospitality sector of the Eastern Cape and investigated the relationships between these factors. Quantitative research was deemed appropriate for this study. Systematic random sampling was employed to select a sample of 332 respondent organisations from the 2012 database of the Eastern Cape Parks and Tourism Agency consisting of formally registered small to medium tourism enterprises. A total of 310 usable questionnaires were finally obtained. Both descriptive and inferential statistics were used in the study. Descriptive statistics were computed to reflect the organisations‟ and respondent managers‟ general characteristics and to summarise their measurement scores. Using inferential statistics, the study further investigated relationships between customer relationship management factors, as well as demographic factors. Data were subjected to exploratory factor analysis and both the validity (refer to section 2.10.1) and reliability (refer to section 2.10.2) of the research instrument was assessed. The relationships between customer relationship management variables were also investigated (refer to section 2.11.4). The research results support an overall significant association between customer relationship management readiness and business strategy, customer strategy, touch points and competencies, skills and technology. Relationships were also explored among customer relationship management factors and demographic characteristics. Significant results were found between perceived business performance and the gender of managers, family businesses and gross annual turnover. The most salient contributions of this research can be summarised as follows. The overview of the importance of tourism and the role of small to medium enterprises in the tourism and hospitality industry of the Eastern Cape will benefit researchers and potential owners who have an interest in this sector. The study contributes to an improved understanding of the factors that should precede customer relationship management. The study established a profile of the small to medium tourism enterprises in the Eastern Cape which can serve as a basis for future research. A measuring instrument for assessing respondents‟ views on the existence of the strategic, operational and organisational factors in their organisations was developed. This instrument showed good internal validity and reliability and can serve as a basis for the same purpose in contexts other than the tourism and hospitality sector. This research has made a contribution toward a largely under-researched area concerning customer relationship management in small to medium enterprises. Recommendations for managers and consideration of future research included the following. Managers need to have a strategic vision and a strong customer-centric focus. Through understanding customers and their needs, offerings can be tailored to maximize the overall value of customers, thereby, improving business performance. Through efficient operational processes in place, enhanced customer service levels can be attained in the organisations. Managers need to effectively manage customer information through data warehousing and technology. Top management commitment is a crucial element for ensuring improved customer services. Managers need to train staff with respect to customer services, thus enhancing CRM. Future researchers can conduct a longitudinal study and investigate the same factors which could impact customer relationship management. A verification of the usefulness of the measuring instrument in examining the determinants of customer relationship management and the level of development regarding other small businesses is suggested. It is recommended that this study be replicated abroad in an effort to verify to what extent the determinants of customer relationship management are evident in small businesses of other countries.
- Full Text:
- Date Issued: 2014
- Authors: Vallabh, Dinesh
- Date: 2014
- Subjects: Customer relations -- Management , Small business -- South Africa -- Eastern Cape , Tourism -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:9322 , http://hdl.handle.net/10948/d1020797
- Description: The role of entrepreneurship in small to medium tourism enterprises is well recognised and acknowledged as a significant contributor to economic development and employment opportunities. Worldwide, small to medium tourism enterprises play a dominant role in the tourism industry. These businesses are often vulnerable to external economic forces and find it increasingly difficult to transform their strategic and operational management to face the challenges placed upon them. This study focuses on small to medium tourism enterprises in the Eastern Cape Province, which is economically the poorest province of South Africa. To ensure the growth and sustainability of small to medium tourism enterprises, owners need to make efficient and effective business decisions regarding the challenges their businesses face. The study examines the factors impacting customer relationship management in the context of small to medium tourism enterprises in the Eastern Cape. Customer relationship management, that is, building relationships with customers, has become of pivotal importance to many organisations as businesses strive to be competitive and profitable. While large organisations practice customer relationship management to enable them to better target profitable customers, improve customer services, enhance customer retention and ultimately improve business performance, small businesses often need assistance in understanding and effecting this complex relationship. The factors that could impact customer relationship management in the organisations are the focus of this study. Three major factors were identified, namely, strategic, operational, and organisational factors. The study furthermore examined the extent to which these factors are present in the tourism and hospitality sector of the Eastern Cape and investigated the relationships between these factors. Quantitative research was deemed appropriate for this study. Systematic random sampling was employed to select a sample of 332 respondent organisations from the 2012 database of the Eastern Cape Parks and Tourism Agency consisting of formally registered small to medium tourism enterprises. A total of 310 usable questionnaires were finally obtained. Both descriptive and inferential statistics were used in the study. Descriptive statistics were computed to reflect the organisations‟ and respondent managers‟ general characteristics and to summarise their measurement scores. Using inferential statistics, the study further investigated relationships between customer relationship management factors, as well as demographic factors. Data were subjected to exploratory factor analysis and both the validity (refer to section 2.10.1) and reliability (refer to section 2.10.2) of the research instrument was assessed. The relationships between customer relationship management variables were also investigated (refer to section 2.11.4). The research results support an overall significant association between customer relationship management readiness and business strategy, customer strategy, touch points and competencies, skills and technology. Relationships were also explored among customer relationship management factors and demographic characteristics. Significant results were found between perceived business performance and the gender of managers, family businesses and gross annual turnover. The most salient contributions of this research can be summarised as follows. The overview of the importance of tourism and the role of small to medium enterprises in the tourism and hospitality industry of the Eastern Cape will benefit researchers and potential owners who have an interest in this sector. The study contributes to an improved understanding of the factors that should precede customer relationship management. The study established a profile of the small to medium tourism enterprises in the Eastern Cape which can serve as a basis for future research. A measuring instrument for assessing respondents‟ views on the existence of the strategic, operational and organisational factors in their organisations was developed. This instrument showed good internal validity and reliability and can serve as a basis for the same purpose in contexts other than the tourism and hospitality sector. This research has made a contribution toward a largely under-researched area concerning customer relationship management in small to medium enterprises. Recommendations for managers and consideration of future research included the following. Managers need to have a strategic vision and a strong customer-centric focus. Through understanding customers and their needs, offerings can be tailored to maximize the overall value of customers, thereby, improving business performance. Through efficient operational processes in place, enhanced customer service levels can be attained in the organisations. Managers need to effectively manage customer information through data warehousing and technology. Top management commitment is a crucial element for ensuring improved customer services. Managers need to train staff with respect to customer services, thus enhancing CRM. Future researchers can conduct a longitudinal study and investigate the same factors which could impact customer relationship management. A verification of the usefulness of the measuring instrument in examining the determinants of customer relationship management and the level of development regarding other small businesses is suggested. It is recommended that this study be replicated abroad in an effort to verify to what extent the determinants of customer relationship management are evident in small businesses of other countries.
- Full Text:
- Date Issued: 2014
Swift heavy ion radiation damage in nanocrystalline ZrN
- Authors: Janse van Vuuren, Arno
- Date: 2014
- Subjects: Zirconium -- Effect of radiation on , Nanocrystals
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10550 , http://hdl.handle.net/10948/d1020147
- Description: ZrN has been identified as a candidate material for use as an inert matrix fuel host for the transmutation of plutonium and minor actinides. These materials will be subjected to large amounts of different types of radiation within the nuclear reactor core. The types of radiation include fission fragments and alpha-particles amongst others. Recent studies suggest that nanocrystalline material may have a higher radiation tolerance than their polycrystalline and bulk counterparts. Some studies have shown that swift heavy ion irradiation may also significantly modulate hydrogen and helium behaviour in materials. This phenomenon is also of considerable practical interest for inert matrix fuel hosts, since these materials accumulate helium via (n,) reactions and will also be subjected to irradiation by fission fragments. The aim of this investigation is therefore to study the effects of fission fragment and alpha particle irradiation on nanocrystalline ZrN. In an effort to simulate the effects of fission fragments on nanocrystalline zirconium nitride different layers (on a Si substrate) of various thicknesses (0.1, 3, 10 and 20 μm) were irradiated with 167 MeV Xe, 250 MeV Kr and 695 MeV Bi ions to fluences in the range from 31012 to 2.61015 cm-2 for Xe, 1×1013 to 7.06×1013 cm-2 for Kr and 1012 to 1013 cm-2 for Bi. The purpose of this irradiation is to simulate the effects of fission fragments on nanocrystalline ZrN. In order to simulate the effects of alpha particles and the combined effects of alpha particles and fission fragments on nanocrystalline ZrN it was irradiated with 30 keV He to fluences between 1016 and 5×1016 cm-2, 167 MeV Xe to fluences between 5×1013 and 1014 cm-2 and also 695 MeV Bi to a fluence of 1.5×1013 cm-2. He/Bi and He/Xe irradiated samples were annealed at temperatures between 600 and 1000 °C. The different irradiated layers were subsequently analysed via X-ray diffraction (XRD), μ-Raman, transmission electron microscopy (TEM) and nano indentation hardness testing (NIH) techniques. XRD, TEM, μ-Raman and NIH results indicate that ZrN has a very high tolerance to the effects of high energy irradiation. The microstructure of nanocrystalline ZrN remains unaffected by electronic excitation effects even at a very high stopping power. TEM and SEM results indicated that post irradiation heat treatment induces exfoliation at a depth that corresponds to the end-of-range of 30 keV He ions. Results from He/Xe irradiated samples revealed that electronic excitation effects, due to Xe ions, suppress helium blister formation and consequently the exfoliation processes. He/Bi samples however do not show the same effects, but this is possibly due to the lower fluence of Bi ions. This suggests that nanocrystalline ZrN is prone to the formation of He blisters which may ultimately lead material failure. These effects may however be mitigated by electronic excitation effects from certain SHIs.
- Full Text:
- Date Issued: 2014
- Authors: Janse van Vuuren, Arno
- Date: 2014
- Subjects: Zirconium -- Effect of radiation on , Nanocrystals
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10550 , http://hdl.handle.net/10948/d1020147
- Description: ZrN has been identified as a candidate material for use as an inert matrix fuel host for the transmutation of plutonium and minor actinides. These materials will be subjected to large amounts of different types of radiation within the nuclear reactor core. The types of radiation include fission fragments and alpha-particles amongst others. Recent studies suggest that nanocrystalline material may have a higher radiation tolerance than their polycrystalline and bulk counterparts. Some studies have shown that swift heavy ion irradiation may also significantly modulate hydrogen and helium behaviour in materials. This phenomenon is also of considerable practical interest for inert matrix fuel hosts, since these materials accumulate helium via (n,) reactions and will also be subjected to irradiation by fission fragments. The aim of this investigation is therefore to study the effects of fission fragment and alpha particle irradiation on nanocrystalline ZrN. In an effort to simulate the effects of fission fragments on nanocrystalline zirconium nitride different layers (on a Si substrate) of various thicknesses (0.1, 3, 10 and 20 μm) were irradiated with 167 MeV Xe, 250 MeV Kr and 695 MeV Bi ions to fluences in the range from 31012 to 2.61015 cm-2 for Xe, 1×1013 to 7.06×1013 cm-2 for Kr and 1012 to 1013 cm-2 for Bi. The purpose of this irradiation is to simulate the effects of fission fragments on nanocrystalline ZrN. In order to simulate the effects of alpha particles and the combined effects of alpha particles and fission fragments on nanocrystalline ZrN it was irradiated with 30 keV He to fluences between 1016 and 5×1016 cm-2, 167 MeV Xe to fluences between 5×1013 and 1014 cm-2 and also 695 MeV Bi to a fluence of 1.5×1013 cm-2. He/Bi and He/Xe irradiated samples were annealed at temperatures between 600 and 1000 °C. The different irradiated layers were subsequently analysed via X-ray diffraction (XRD), μ-Raman, transmission electron microscopy (TEM) and nano indentation hardness testing (NIH) techniques. XRD, TEM, μ-Raman and NIH results indicate that ZrN has a very high tolerance to the effects of high energy irradiation. The microstructure of nanocrystalline ZrN remains unaffected by electronic excitation effects even at a very high stopping power. TEM and SEM results indicated that post irradiation heat treatment induces exfoliation at a depth that corresponds to the end-of-range of 30 keV He ions. Results from He/Xe irradiated samples revealed that electronic excitation effects, due to Xe ions, suppress helium blister formation and consequently the exfoliation processes. He/Bi samples however do not show the same effects, but this is possibly due to the lower fluence of Bi ions. This suggests that nanocrystalline ZrN is prone to the formation of He blisters which may ultimately lead material failure. These effects may however be mitigated by electronic excitation effects from certain SHIs.
- Full Text:
- Date Issued: 2014
The development of functionalized electrospun nanofibers for the control of pathogenic microorganisms in water.
- Authors: Kleyi, Phumelele Eldridge
- Date: 2014
- Subjects: Electrospinning , Nanofibers , Pathogenic microorganisms , Pathogenic microorganisms -- Detection , Drinking water -- Microbiology , Water quality -- Measurement , Imidazoles , Spectrum analysis , Anti-infective agents , Polymerization
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4497 , http://hdl.handle.net/10962/d1013134
- Description: The thesis presents the development of functionalized electrospun nylon 6 nanofibers for the eradication of pathogenic microorganisms in drinking water. Imidazole derivatives were synthesized as the antimicrobial agents and were characterized by means of NMR spectroscopy, IR spectroscopy, elemental analysis and X-ray crystallography. The first set of compounds (2-substituted N-alkylimidazoles) consisted of imidazole derivatives substituted with different alkyl groups (methyl, ethyl, propyl, butyl, heptyl, octyl, decyl and benzyl) at the 1-position and various functional groups [carboxaldehyde (CHO), alcohol (CH2OH) and carboxylic acid (COOH)] at the 2-position. It was observed that the antimicrobial activity of the compounds increased with increasing alkyl chain length and decreasing pKa of the 2-substituent. It was also observed that the antimicrobial activity was predominantly against a Gram-positive bacterial strains [Staphylococcus aureus (MIC = 5-160 μg/mL) and Bacillus subtilis subsp. spizizenii (MIC = 5-20 μg/mL)], with the latter being the more susceptible. However, the compounds displayed poor antimicrobial activity against Gram-negative bacterial strain, E. coli (MIC = 150- >2500 μg/mL) and did not show any activity against the yeast, C. albicans. The second set of compounds consisted of the silver(I) complexes containing 2-hydroxymethyl-N-alkylimidazoles. The complexes displayed a broad spectrum antimicrobial activity towards the microorganisms that were tested and their activity [E. coli (MIC = 5-40 μg/mL), S. aureus (MIC = 20-80 μg/mL), Bacillus subtilis subsp. spizizenii (MIC = 5-40 μg/mL) and C. albicans (MIC = 40-80 μg/mL)] increased with the alkyl chain length of the 2-hydroxymethyl-N-alkylimidazole. The third set of compounds consisted of the vinylimidazoles containing the vinyl group either at the 1-position or at the 4- or 5- position. The imidazoles with the vinyl group at the 4- or 5-position contained the alkyl group (decyl) at the 1-position. For the fabrication of the antimicrobial nanofibers, the first two sets of imidazole derivatives (2-substituted N-alkylimidazoles and silver(I) complexes) were incorporated into electrospun nylon 6 nanofibers while the third set (2-substituted vinylimidazoles) was immobilized onto electrospun nylon 6 nanofibers employing the graft polymerization method. The antimicrobial nylon nanofibers were characterized by IR spectroscopy and SEM-EDAX (EDS). The electrospun nylon 6 nanofibers incorporated with 2-substituted N-alkylimidazoles displayed moderate to excellent levels of growth reduction against S. aureus (73.2-99.8 percent). For the electrospun nylon 6 nanofibers incorporated with silver(I) complexes, the levels of growth reduction were >99.99 percent, after the antimicrobial activity evaluation using the shake flask method. Furthermore, the grafted electrospun nylon 6 nanofibers showed excellent levels of growth reduction for E. coli (99.94-99.99 percent) and S. aureus (99.93-99.99 percent). The reusability results indicated that the grafted electrospun nylon 6 nanofibers maintained the antibacterial activity until the third cycle of useage. The cytotoxicity studies showed that grafted electrospun nylon 6 nanofibers possess lower cytotoxic effects on Chang liver cells with IC50 values in the range 23.48-26.81 μg/mL. The thesis demonstrated that the development of antimicrobial electrospun nanofibers, with potential for the eradication of pathogenic microoganisms in water, could be accomplished by incorporation as well as immobilization strategies.
- Full Text:
- Date Issued: 2014
- Authors: Kleyi, Phumelele Eldridge
- Date: 2014
- Subjects: Electrospinning , Nanofibers , Pathogenic microorganisms , Pathogenic microorganisms -- Detection , Drinking water -- Microbiology , Water quality -- Measurement , Imidazoles , Spectrum analysis , Anti-infective agents , Polymerization
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4497 , http://hdl.handle.net/10962/d1013134
- Description: The thesis presents the development of functionalized electrospun nylon 6 nanofibers for the eradication of pathogenic microorganisms in drinking water. Imidazole derivatives were synthesized as the antimicrobial agents and were characterized by means of NMR spectroscopy, IR spectroscopy, elemental analysis and X-ray crystallography. The first set of compounds (2-substituted N-alkylimidazoles) consisted of imidazole derivatives substituted with different alkyl groups (methyl, ethyl, propyl, butyl, heptyl, octyl, decyl and benzyl) at the 1-position and various functional groups [carboxaldehyde (CHO), alcohol (CH2OH) and carboxylic acid (COOH)] at the 2-position. It was observed that the antimicrobial activity of the compounds increased with increasing alkyl chain length and decreasing pKa of the 2-substituent. It was also observed that the antimicrobial activity was predominantly against a Gram-positive bacterial strains [Staphylococcus aureus (MIC = 5-160 μg/mL) and Bacillus subtilis subsp. spizizenii (MIC = 5-20 μg/mL)], with the latter being the more susceptible. However, the compounds displayed poor antimicrobial activity against Gram-negative bacterial strain, E. coli (MIC = 150- >2500 μg/mL) and did not show any activity against the yeast, C. albicans. The second set of compounds consisted of the silver(I) complexes containing 2-hydroxymethyl-N-alkylimidazoles. The complexes displayed a broad spectrum antimicrobial activity towards the microorganisms that were tested and their activity [E. coli (MIC = 5-40 μg/mL), S. aureus (MIC = 20-80 μg/mL), Bacillus subtilis subsp. spizizenii (MIC = 5-40 μg/mL) and C. albicans (MIC = 40-80 μg/mL)] increased with the alkyl chain length of the 2-hydroxymethyl-N-alkylimidazole. The third set of compounds consisted of the vinylimidazoles containing the vinyl group either at the 1-position or at the 4- or 5- position. The imidazoles with the vinyl group at the 4- or 5-position contained the alkyl group (decyl) at the 1-position. For the fabrication of the antimicrobial nanofibers, the first two sets of imidazole derivatives (2-substituted N-alkylimidazoles and silver(I) complexes) were incorporated into electrospun nylon 6 nanofibers while the third set (2-substituted vinylimidazoles) was immobilized onto electrospun nylon 6 nanofibers employing the graft polymerization method. The antimicrobial nylon nanofibers were characterized by IR spectroscopy and SEM-EDAX (EDS). The electrospun nylon 6 nanofibers incorporated with 2-substituted N-alkylimidazoles displayed moderate to excellent levels of growth reduction against S. aureus (73.2-99.8 percent). For the electrospun nylon 6 nanofibers incorporated with silver(I) complexes, the levels of growth reduction were >99.99 percent, after the antimicrobial activity evaluation using the shake flask method. Furthermore, the grafted electrospun nylon 6 nanofibers showed excellent levels of growth reduction for E. coli (99.94-99.99 percent) and S. aureus (99.93-99.99 percent). The reusability results indicated that the grafted electrospun nylon 6 nanofibers maintained the antibacterial activity until the third cycle of useage. The cytotoxicity studies showed that grafted electrospun nylon 6 nanofibers possess lower cytotoxic effects on Chang liver cells with IC50 values in the range 23.48-26.81 μg/mL. The thesis demonstrated that the development of antimicrobial electrospun nanofibers, with potential for the eradication of pathogenic microoganisms in water, could be accomplished by incorporation as well as immobilization strategies.
- Full Text:
- Date Issued: 2014
Synthetic analogues of marine bisindole alkaloids as potent selective inhibitors of MRSA pyruvate kinase
- Veale, Clinton Gareth Lancaster
- Authors: Veale, Clinton Gareth Lancaster
- Date: 2014 , 2014-04-02
- Subjects: Alkaloids , Pyruvate kinase , Staphylococcus aureus , Antibiotics , Sponges -- South Africa , Imidazoles , Biological assay , Antibacterial agents
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4563 , http://hdl.handle.net/10962/d1020893
- Description: Globally, methicillin resistant Staphylococcus aureus (MRSA) has become increasingly difficult to manage in the clinic and new antibiotics are required. The structure activity relationship (SAR) study presented in this thesis forms part of an international collaborative effort to identify potent and selective inhibitors of an MRSA pyruvate kinase (PK) enzyme target. In earlier work the known marine natural product bromodeoxytopsentin (1.6), isolated from a South African marine sponge Topsentia pachastrelloides, exhibited selective and significant inhibition of MRSA PK (IC₅₀ 60 nM). Accordingly bromodeoxytopsentin provided the initial chemical scaffold around which our SAR study was developed. Following a comprehensive introduction, providing the necessary background to the research described in subsequent Chapters, this thesis has been divided into three major parts. Part one (Chapter 2) documents the synthesis of two natural imidazole containing topsentin analogues 1.40, 1.46, five new synthetic analogues 1.58—1.61, 2.104. In the process we developed a new method for the synthesis of topsentin derivatives via selenium dioxide mediated oxidation of N-Boc protected 3-acetylindoles to yield glyoxal intermediates which were subsequently cyclized and deprotected to yield the desired products. Interestingly we were able to demonstrate a delicate relationship between the relative equivalents of selenium dioxide and water used during the oxidation step, careful manipulation of which was required to prevent the uncontrolled formation of side products. Synthetic compounds 1.40, 1.46, 1.58—1.61 were found to be potent inhibitors of MRSA PK (IC₅₀ 238, 2.1, 23, 1.4, 6.3 and 3.2 nM respectively) with 1000-10000 fold selectivity for MRSA PK over four human orthologs. In the second part of this thesis (Chapter 3) we report the successful synthesis of a cohort of previously unknown thiazole containing bisindole topsentin analogues 1.62—1.68 via a Hantzsch thiazole synthesis. Bioassay results revealed that these compounds were only moderate inhibitors of MRSA PK (IC₅₀ 5.1—20 μM) which suggested that inhibitory activity was significantly reduced upon substitution of the central imidazole ring of topsentin type analogues with a thiazole type ring. In addition in Chapter 3 we describe unsuccessful attempts to regiospecifically synthesize oxazole and imidazole topsentin analogues through a similar Hantzsch method. As a consequence of our efforts in this regard we investigated three key reactions in depth, namely the synthesis of 2.2, 3.38, 3.40, 3.41 via α-bromination of 3-acetylindole and the synthesis of indolyl-3-carbonylnitriles 2.13, 3.45—3.47 and α-oxo-1H-indole-3-thioacetamides 3.48—3.51. The investigation of the latter led to the isolation and elucidation of two anomalous N,N-dimethyl-1H-indole-3-carboxamides 3.52 and 3.53. Finally the third part of this thesis (Chapter 4) deals with in silico assessment of the binding of both the imidazole and thiazole containing bisindole alkaloids to the MRSA PK protein which initially guided our SAR studies. In this chapter we reveal that there appears to be no correlation between in silico binding predictions and in vitro MRSA PK inhibitory bioassay data. Superficially it seems that binding energy as determined by the docking program used for these studies correlated with the size of the indole substituents and did not reflect IC₅₀ MRSA PK inhibitory data. Although this led us to computationally explore possible alternative binding sites no clear alternative has been identified.
- Full Text:
- Date Issued: 2014
- Authors: Veale, Clinton Gareth Lancaster
- Date: 2014 , 2014-04-02
- Subjects: Alkaloids , Pyruvate kinase , Staphylococcus aureus , Antibiotics , Sponges -- South Africa , Imidazoles , Biological assay , Antibacterial agents
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4563 , http://hdl.handle.net/10962/d1020893
- Description: Globally, methicillin resistant Staphylococcus aureus (MRSA) has become increasingly difficult to manage in the clinic and new antibiotics are required. The structure activity relationship (SAR) study presented in this thesis forms part of an international collaborative effort to identify potent and selective inhibitors of an MRSA pyruvate kinase (PK) enzyme target. In earlier work the known marine natural product bromodeoxytopsentin (1.6), isolated from a South African marine sponge Topsentia pachastrelloides, exhibited selective and significant inhibition of MRSA PK (IC₅₀ 60 nM). Accordingly bromodeoxytopsentin provided the initial chemical scaffold around which our SAR study was developed. Following a comprehensive introduction, providing the necessary background to the research described in subsequent Chapters, this thesis has been divided into three major parts. Part one (Chapter 2) documents the synthesis of two natural imidazole containing topsentin analogues 1.40, 1.46, five new synthetic analogues 1.58—1.61, 2.104. In the process we developed a new method for the synthesis of topsentin derivatives via selenium dioxide mediated oxidation of N-Boc protected 3-acetylindoles to yield glyoxal intermediates which were subsequently cyclized and deprotected to yield the desired products. Interestingly we were able to demonstrate a delicate relationship between the relative equivalents of selenium dioxide and water used during the oxidation step, careful manipulation of which was required to prevent the uncontrolled formation of side products. Synthetic compounds 1.40, 1.46, 1.58—1.61 were found to be potent inhibitors of MRSA PK (IC₅₀ 238, 2.1, 23, 1.4, 6.3 and 3.2 nM respectively) with 1000-10000 fold selectivity for MRSA PK over four human orthologs. In the second part of this thesis (Chapter 3) we report the successful synthesis of a cohort of previously unknown thiazole containing bisindole topsentin analogues 1.62—1.68 via a Hantzsch thiazole synthesis. Bioassay results revealed that these compounds were only moderate inhibitors of MRSA PK (IC₅₀ 5.1—20 μM) which suggested that inhibitory activity was significantly reduced upon substitution of the central imidazole ring of topsentin type analogues with a thiazole type ring. In addition in Chapter 3 we describe unsuccessful attempts to regiospecifically synthesize oxazole and imidazole topsentin analogues through a similar Hantzsch method. As a consequence of our efforts in this regard we investigated three key reactions in depth, namely the synthesis of 2.2, 3.38, 3.40, 3.41 via α-bromination of 3-acetylindole and the synthesis of indolyl-3-carbonylnitriles 2.13, 3.45—3.47 and α-oxo-1H-indole-3-thioacetamides 3.48—3.51. The investigation of the latter led to the isolation and elucidation of two anomalous N,N-dimethyl-1H-indole-3-carboxamides 3.52 and 3.53. Finally the third part of this thesis (Chapter 4) deals with in silico assessment of the binding of both the imidazole and thiazole containing bisindole alkaloids to the MRSA PK protein which initially guided our SAR studies. In this chapter we reveal that there appears to be no correlation between in silico binding predictions and in vitro MRSA PK inhibitory bioassay data. Superficially it seems that binding energy as determined by the docking program used for these studies correlated with the size of the indole substituents and did not reflect IC₅₀ MRSA PK inhibitory data. Although this led us to computationally explore possible alternative binding sites no clear alternative has been identified.
- Full Text:
- Date Issued: 2014