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The role of the church in an urban African society

- Dubb, Allie A

Authors: Dubb, Allie A
Date: 1961
Subjects: Bhengu, Nicholas B H, 1909- , Pentecostal churches -- South Africa -- East London
Language: English
Type: Thesis , Masters , MA
Identifier: vital:3361 , http://hdl.handle.net/10962/d1011563 , Bhengu, Nicholas B H, 1909- , Pentecostal churches -- South Africa -- East London
Description: This study is based on research carried out in East London, South Africa during the period September 1957 to August 1959 as an Assistant Research Officer of the Institute for Social and Economic Research, Rhodes University. The study is presented in three parts and its theme, broadly speaking, is the role of the church in an urban African society. In Part I, some aspects of the African Church in East London are discussed in general terms and an attempt was made to relate our own material with the findings of other researchers. Emerging from this discussion we have concluded that the Church could potentially play an important part in combating the social disorganization characteristic of urban locations in South Africa, but that on the whole this potential has not been fully exploited.
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Date Issued: 1961

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Discussing the evidence : small group work in the history class

- Robinson, Andrew Meredith Lewin

Authors: Robinson, Andrew Meredith Lewin
Date: 1988
Subjects: History -- Study and teaching (Secondary) Group work in education
Language: English
Type: Thesis , Masters , MEd
Identifier: vital:1863 , http://hdl.handle.net/10962/d1004588
Description: This is a small-scale research study on the discovery method of teaching history through the medium of small-group discussion. The study begins with a brief outline of the theoretical background to these topics, as well as of some of the extant research in the field. The class selected for the study is the standard seven class of a boys' high school. After the researcher has instructed the whole standard in an historical area which is unfamiliar to the pupils, twelve groups of three each are selected and withdrawn from the rest of the class, one group at a time. These thirty-six pupils become the "experimental" group; the rest of the pupils become the "control" group . The groups are selected according to different intellectual criteria and presented with stimulus material of one of three kinds, which is intended to aid them in their discourse. Each group is given the same set of three questions to discuss and, without further assistance by the researcher, the discussion takes place. This is recorded on audio-tape. After all the group discussions have been recorded, an assessment test is given to the whole standard, both experimental and control pupils. At the end of the school term a compulsory examination question is inserted in the history examination. The statistical data forthcoming from these assessments are correlated and the results analysed. Meanwhile, transcripts of all the group discussions have been made and these are analysed on a qualitative basis in terms of the groups' intellectual composition and according to the type of stimulus material used, and the results are recorded. The concept of "leaderless" groups is briefly discussed in the light of the dealings of the various groups in the study. The researcher finally feels justified in concluding that small groups are an ideal medium for the handling of evidence- based learning in history. He also has certain observations to make on the performance of groups of mixed (as opposed to homogeneous) ability as well as on the success of certain types of stimulus material towards initiating profitable discussion.
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Date Issued: 1988

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Contesting masculinities: a study of selected texts of resistance to conscription into the South African Defence Force (SADF) in the 1980s

- Mason, Paul

Authors: Mason, Paul
Date: 2016
Language: English
Type: Thesis , Doctoral , PhD
Identifier: vital:2332 , http://hdl.handle.net/10962/d1020842
Description: The theoretical framework for this thesis and analysis of primary texts revolves around the problem of conscription into the South African Defence Force (SADF) in the 1980s. The ideology of masculinity that underpinned and sustained the practice of conscription is referred to throughout as the hegemonic version. This term is interchangeable with others, namely masculinism and ‗the real man.‘ The aim is to interpret the selected texts for strains of resistance to the practice of conscription and its assumptions as to what to what constitutes the natural or real man. In the Introduction to this thesis I begin by explaining the personal dimension of my role as researcher, after which I motivate my research project and explain its theoretical and methodological orientation, focusing on the concepts that play a significant role in analysis of the primary texts. The Introduction concludes with an outline of the content of Chapters 1–5. Chapter 1 begins with a brief discussion, on the general level, of the practice of conscription and resistance to it, and proceeds to a concern with conscription in 1980s South Africa. Attention is paid to prevailing attitudes towards gender and sexuality within both the SADF and the End Conscription Campaign (ECC). Discussion of gender and sexuality as constructs of identity proceeds to a focus on the conceptual tools for textual analysis provided by theories of masculinity. The final section of this chapter pays attention to specific post-structuralist notions of identity that serve analysis of the primary texts, that is, the notions of the subject, agency and the author. Having engaged mainly with secondary texts in Chapter 1, Chapter 2 presents the first sustained critical engagement with primary texts in which resistance was expressed against the institution of conscription and the hegemonic version of masculinity that underpinned it. These expressions of resistance occurred within a rock music counter-culture of the period, known as the Voëlvry movement. Attention is given to overlaps or links between this counter-culture and that of America in the 1960s, as well echoes between the Vietnam and Border Wars. Analysis of these links is applied to a memoir selected for its appropriateness. Threaded through the chapter is a concern with expressions of masculine identity within the Voëlvry counter-culture, the SADF and the ECC. Chapter 3 focuses on three novels and one collection of short stories, each narrated in the first person and written by gay authors who performed their National Service. Attention is paid to the protagonists‘ perceptions of themselves, their troubled relationships with their fathers, and the struggle to come out within a context that prohibited them from doing so. Chapter 4 concerns three wartime memoirs and two written by men who refused to perform their National Service. Underlying concerns in this chapter are the question of fact versus fiction in the genre of the memoir, authors‘ perceptions of and relationships with women, and expressions of vulnerability. Chapter 5 concentrates on the interviews that comprise the Appendix. The chapter establishes its theoretical ground by focusing on principles of narrative structure and the relation of personal to narrative identity. The chapter pays attention to the displays of power and the vulnerabilities of both veteran soldiers and resisters. Theory deployed in analysis of the primary texts serves the principal concerns articulated in the title to the thesis.
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Date Issued: 2016

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A study of factors enhancing truck driver retention at Tanker Services, Imperial Logistics, South Africa

- Goss, Cayley Amy

Authors: Goss, Cayley Amy
Date: 2016
Language: English
Type: Thesis , Masters , MBA
Identifier: vital:868 , http://hdl.handle.net/10962/d1021250
Description: The aim of this qualitative study was to gain an understanding of the factors that enhance truck driver retention at Tanker Services, Imperial Logistics, South Africa. The specific objectives of the study were to (1) explore factors which influence the retention of truck drivers from the perspectives of immediate supervisors of these drivers at Tanker Services Branches in Durban, Johannesburg, and Cape Town; (2) to identify the means Tanker Services adopts in meeting factors influential to truck driver retention; and (3) to provide recommendations on how to successfully retain truck drivers in this logistics organisation in South Africa. The research methodology of this study involved interviewing ten immediate managers of truck drivers at Tanker Services, Imperial Logistics. Specifically, data was collected through the use of individual, in-depth and semi-structured interviews to investigate the most influential factors affecting truck driver retention. The results of this research outline factors important to the truck drivers at Tanker Services from the perspectives of their immediate supervisors - most of whom were previously truck drivers themselves. The findings of this research identified the general factors that affect Tanker Services Truck drivers as follows: formal and informal rewards, competitive compensation, a work environment of quality equipment, high safety standards and recreational facilities. Furthermore, interpersonal relations and company reputation were found most influential to truck drivers in this South African logistics context.
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Date Issued: 2016

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Implementing performance management at local government level in South Africa : a case study on the impact of organisational culture

- Williams, Quinton Walter

Authors: Williams, Quinton Walter
Date: 2006
Subjects: Buffalo City (South Africa) Local government -- South Africa Municipal government -- South Africa Performance -- Management -- South Africa Corporate culture -- South Africa
Language: English
Type: Thesis , Masters , MBA
Identifier: vital:749 , http://hdl.handle.net/10962/d1003870
Description: Local Government in South Africa has undergone much transformation since 2000. Although much of the change has been to correct imbalances, inequities and disparities within our local communities as a result of Apartheid, change has also been motivated by National Government’s realisation that, as with governments throughout the world, there is a need to modernise all spheres of Government. Part of this transformation process at a local government level in South Africa has been to ensure that municipalities become more responsive to the communities’ needs. The guiding principles for this transformation are contained in the White Paper on the Transformation of the Public Service (1995) and the Batho Pele White Paper (1997). This has informed the Municipal Systems Act: Act 32 of 2000 of which Chapter 6 determines that municipalities will have a performance management system to promote a culture of performance management amongst the political structures, political office bearers, councillors and administration. The performance management system must ensure that the municipality administers its affairs in an economical, effective, efficient and accountable manner. A literature review contained in this research, indicates that internationally, implementing performance management systems at a local government level is impact upon by a number of factors such as the organizational culture of an institution. This research, which has been grounded within a constructivist paradigm, describes the impact organizational culture has had on the implementation process of the performance management system at Buffalo City Municipality. Interviews were conducted amongst the Section 57 employees (i.e. the Directors) and those employees directly responsible for implementing performance management. The four Directors, two General Managers and the portfolio councilor were interviewed. Semi-structured interviews were conducted with the interviewees and this culminated in a total of 10 hours of interviewing. The protocols were analyzed using the guidelines suggested by Boyatzis (1998) and the findings are detailed in two chapters. The findings of the research were that the implementation of the performance management system at Buffalo City Municipality has been impacted on by the dichotomy between the political and administrative leadership, resulting in non-implementation of council resolutions, the lack of an organizational strategy, poor institutional arrangements and inadequate resource allocation, are reported. However, the most important finding was the impact that a culture of fear has had on the implementation process. This culture of fear and its impact on the implementation of performance management system is described as the most pervasive and insidious of all the findings to have negatively impacted on the implementation process. This research ends with recommendations for further research and it is argued that each organization has its own unique organizational culture. The conclusion is that no single typology, as contained in the literature, which can account for the specific impact organizational culture will have on the implementation process of a performance management system at local government level in South Africa. Consequently, implementers of performance management systems must assess the unique characteristics of each organization’s culture prior to implementation, in order to evaluate its impact that the organizational culture can have on the process.
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Date Issued: 2006

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An investigation of how newly appointed team leaders in an automotive manufacturing organisation experience the role transition from specialists to team leaders

- Mzelemu, Patrick Sbusiso

Authors: Mzelemu, Patrick Sbusiso
Date: 2022-10-14
Subjects: Leadership , Automobile industry executives , Role expectation , Identity (Psychology) , Personnel management , Organizational behavior
Language: English
Type: Academic theses , Master's theses , text
Identifier: http://hdl.handle.net/10962/403036 , vital:69916
Description: The purpose of this study is to investigate and understand how specialists who are newly appointed team leaders in an automotive manufacturing organisation experience the transition from specialists to team leaders. The role of leading others in an organisation is linked to human resource leadership. The human resource is highlighted as a valuable resource as it is the only thinking resource in an organisation. It also influences cost and quality and it is central to the organisation's competitive advantage. Consequently, any interruptions or lack of effective management of the human resource will result in a loss of value that the human resource brings into the organisation since they maximise the use of all other resources. The role transitioning process takes place in three phases. These are the separation, transitioning and incorporation phases. In the separation phase, the transitioning individuals have difficulty detaching from their previous role; the individuals still having the urge to do the work for their subordinates instead of delegating illustrate this. In the transition phase, the individuals in the study experienced the anxiety of wanting to make the new role a success whilst experiencing a sense of lack of belonging due to not being in the familiar old role and not entrenched in the new role. In the incorporation phase, the transitioning individuals experience a sense of stability where they are comfortable acting in the new role. Problem: This study aims to answer the question of how newly appointed team leaders in an automotive manufacturing organisation experience role transition from specialists to team leaders Method: The study will be employing the qualitative thematic deductive method. The target population consists of team leaders who have transitioned into the team leader position in the past two years in different departments. The data was collected by way of face-to-face semistructured interviews with a sample size of seven participants. Data analysis was conducted with a method that is consistent with thematic analysis. 3 Key Findings: Individuals transitioning have urgencies to perform their previous roles in the early phase; during the transition phase, they have anxiety because they are not yet successful in the new role, and in the final phase, they have become comfortable with their new roles and their new identities. Implications: The study's outcome is to identify insights and resultant recommendations for non-leading specialists transitioning into roles where they have to lead others. The study will add to the research in the field of leadership behaviour and organisational behaviour. , Thesis (MBA) -- Faculty of Commerce, Rhodes Business School, 2022
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Date Issued: 2022-10-14

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Reading William Blake and T.S. Eliot: contrary poets, progressive vision

- Rayneard, Max James Anthony

Authors: Rayneard, Max James Anthony
Date: 2002
Subjects: Blake, William, 1757-1827 -- Criticism and interpretation , Eliot, T. S. (Thomas Stearns), 1888-1965 -- Criticism and interpretation
Language: English
Type: Thesis , Masters , MA
Identifier: vital:2279 , http://hdl.handle.net/10962/d1007545 , Blake, William, 1757-1827 -- Criticism and interpretation , Eliot, T. S. (Thomas Stearns), 1888-1965 -- Criticism and interpretation
Description: Many critics resort to explaining readers' experiences of poems like William Blake's Jerusalem and T.S. Eliot's Four Quartets in terms of "spirituality" or "religion". These experiences are broadly defined in this thesis as jouissance (after Roland Barthes' essay The Pleasure of the Text) or "experience qua experience". Critical attempts at the reduction of jouissance into abstract constructs serve merely as stopgap measures by which critics might avoid having to account for the limits of their own rational discourse. These poems, in particular, are deliberately structured to preserve the reader's experience of the poem from reduction to any particular meta-discursive construct, including "the spiritual". Through a broad application of Rezeption-Asthetik principles, this thesis demonstrates how the poems are structured to direct readers' faculties to engage with the hypothetical realm within which jouissance occurs, beyond the rationally abstractable. T.S. Eliot's poetic oeuvre appears to chart his growing confidence in non-rational, pre-critical faculties. Through "The Love Song of J. Alfred Prufrock", The Waste Land, and Four Quartets, Eliot's poetry becomes gradually less prescriptive of the terms to which the experience of his poetry might be reduced. In Four Quartets he finally entrusts readers with a great deal of responsibility for "co-creating" the poem's significance. Like T.S . Eliot, although more consistently throughout his oeuvre, William Blake is similarly concerned with the validation of the reader's subjective interpretative/creative faculties. Blake's Jerusalem is carefully structured on various intertwined levels to rouse and exercise in the reader what the poet calls the "All Glorious Imagination" (Keynes 1972: 679). The jouissance of Jerusalem or Four Quartets is located in the reader's efforts to co-create the significance of the poems. It is only during a direct engagement with this process, rather than in subsequent attempts to abstract it, that the "experience qua experience" may be understood.
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Date Issued: 2002

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A critical investigation of a planned organisation change initiative within an educational institution in the Eastern Cape Province

- Irvine, Margaret Hillian

Authors: Irvine, Margaret Hillian
Date: 2000
Subjects: School management and organization -- South Africa -- Evaluation Education and state Educational change -- South Africa -- Eastern Cape Education -- Economic aspects Organizational change -- South Africa -- Management Non-governmental organizations -- South Africa -- Eastern Cape School management and organization -- South Africa -- Eastern Cape
Language: English
Type: Thesis , Masters , MEd
Identifier: vital:1479 , http://hdl.handle.net/10962/d1003360
Description: South Africa is living is turbulent times at present. Non-government educational organisations are challenged by changes in education policy and by scarcity of donor funding for their work. This study focuses on the management of organisation change in a non-government organisation (NGO) working in rural areas of the Eastern Cape Province. I undertook the research to gain a clearer understanding of the management of organisational change. I used a third-wave change management approach, the future search conference, to conduct the process of change with the NGO. It focuses on the positive aspects of the organisation, its potential and its desired future. I conducted both the study and the future search conference as participatory action research, which involved the participants in the cycles of planning, action, observation and reflection and thus built ownership of the solutions they generated. I used the accounts of the activities arising from the future search conference, minutes of meetings, semistructured interviews and observation of behaviour to gather data. I analysed the data using triangulation, and in particular, space triangulation, to minimise the impact of the differences in culture and language use in the facilitator and participants. Analysis of the data collected revealed in the NGO that change and transformation are slow processes requiring ongoing support from the OD consultant. The staff defined organisational effectiveness, the goal of organisational change initiatives, in terms of fundraising ability. This ability embraces many of the qualities of a learning organisation and open systems thinking, two requirements for successful organisational change. In the NGO both organisation development and transformation were processes as well as products, and changes could not easily be measured until after the processes were completed. Organisational culture, and in particular the juxtaposition of the values of the organisation and staff and those of its partners and clients, played an important role in transformation. The differences lay in a ‘being’ and a ‘task’ orientation and the staff’s responsibility lay in building connections between the two. The staff received the approach of the future search conference well and there was an equally good fit between the future search conference and participatory action research. This needs to be investigated further with regard to change management in South African organisations.
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Date Issued: 2000

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Interaction and transaction: a study of conciliar behaviour in a Black South African township

- De Jongh, Michael

Authors: De Jongh, Michael
Date: 1979
Subjects: Social interaction , Conciliary behaviour , Black people , Townships , Port Elizabeth , Eastern Cape (South Africa) , Government , Local government
Language: English
Type: Thesis , Doctoral , PhD
Identifier: vital:2086 , http://hdl.handle.net/10962/d1001603
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Date Issued: 1979

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Photodynamic antimicrobial chemotherapy activities of porphyrin- and phthalocyanine-platinum nanoparticle conjugates

- Managa, Muthumuni Elizabeth

Authors: Managa, Muthumuni Elizabeth
Date: 2015
Subjects: Photochemotherapy , Anti-infective agents , Porphyrins , Phthalocyanines , Platinum , Nanoparticles , Bioconjugates , Electrospinning
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:4539 , http://hdl.handle.net/10962/d1017919
Description: This work reports on the conjugation of differently shaped Pt nanoparticles (PtNPs) with ClGa(III) 5,10,15,20-tetrakis-(4-carboxyphenyl) porphyrin (1) as well as chloro - (5,10,15,20-tetrakis (4- (4- carboxy phenycarbonoimidoyl) phenyl) porphyrinato) gallium(III) (2) The work also reports on platination of dihydroxosilicon octacarboxyphthalocyanine (OH)₂SiOCPc (3) to give dihydroxosilicontris(diaquaplatinum)octacarboxyphthalocyanine (OH)₂SiOCPc(Pt)₃ (4). The resulting conjugates were used for photodynamic antimicrobial chemotherapy against S. aureus, E. coli and C. albicans. The degree of photo-inactivation is dependent on concentration of the conjugates, light dose (fluence) and illumination time. The log reduction obtained for 1 when conjugated to cubic PtNPs was 4.64 log (which indicate 99.99 percent of the bacteria have been killed), which is much higher than 3.94 log unit for 1-hexagonal PtNPs and 3.31 log units for 1-unshaped PtNPs. Complex 2 conjugated to hexagonal PtNPs showed 18 nm red shift in the Soret band when compared to 2 alone. Complex 2 and 2-hexagonal PtNPs as well showed promising photodynamic antimicrobial chemotherapy (PACT) activity against S. aureus, E. coli and C. albicans in solution where the log reduction obtained was 4.92, 3.76, and 3.95 respectively for 2-hexagonal PtNPs. The singlet oxygen quantum yields obtained were higher at 0.56 for 2-hexagonl PtNPs in DMF while that of 2 was 0.52 in the same solvent. This resulted in improved PACT activity for 2-hexagonal PtNPs compared to 2. Complex 4 showed slight blue shifting of the absorption spectrum when compared to complex 3 The antimicrobial activity of 4 were promising as the highest log reduction value was observed when compared to the porphyrin conjugates.
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Date Issued: 2015

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Interactions between three biological control agents of water hyacinth, Eichhornia crassipes (Mart.) Solms (Pontederiaceae) in South Africa

- Petela, Nomvume

Authors: Petela, Nomvume
Date: 2018
Subjects: Water hyacinth -- South Africa , Water hyacinth -- Biological control -- South Africa , Aquatic weeds -- Biological control -- South Africa , Curculionidae , Delphacidae , Miridae , Neochetina eichhorniae Warner , Megamelus scutellaris Berg , Eccritotarsus eichhorniae Henry
Language: English
Type: text , Thesis , Masters , MSc
Identifier: http://hdl.handle.net/10962/60676 , vital:27814
Description: Water hyacinth, Eichhomia crassipes (Mart.) Solms (Pontederiaceae) is a free-floating perennial weed that is regarded as the worst aquatic weed in the world because of its negative impacts on aquatic ecosystems. It is native to the Amazon Basin of South America, but since the late 1800s has spread throughout the world. The first record of the weed in South Africa was noted in 1908 on the Cape Flats and in KwaZulu-Natal, but it is now dispersed throughout the country. Mechanical and chemical control methods have been used against the weed, but biological control is considered the most cost-effective, sustainable and environmentally friendly intervention. Currently, nine biological control agents have been released against water hyacinth in South Africa, and Neochetina eichhorniae Warner (Coleoptera: Curculionidae) is used most widely to control it. However, in some sites, water hyacinth mats have still not been brought under control because of eutrophic waters and cool temperatures. It was therefore necessary to release new biological control agents to complement the impact of N. eichhorniae. Megamelus scutellaris Berg (Hemiptera: Delphacidae) was released in 2013, but little is known about how it interacts with other agents already present in South Africa. It is likely to compete with the established biological control agent, Eccritotarsus eichhorniae Henry (Heteroptera: Miridae), because they are both sap suckers. On the other hand, N. eichhorniae is the most widespread and thus the most important biological control agent for water hyacinth. The aim of this study, then, was to determine the interactions between the two sap-sucking agents in South Africa that presumably occupy similar niches on the plant, and the interaction between M. scutellerais and N. eichhorniae, the most widely distributed and abundant agent in South Africa. Three experiments were conducted at the Waainek Research Facility at Rhodes University, Grahamstown, Eastern Cape, South Africa. Plants were grown for two weeks and insect species were inoculated singly or in combination. Water hyacinth, plant growth parameters and insect parameters were measured every 14 days for a period of 12 weeks. The results of the study showed that feeding by either E. eichhorniae or M. scutellaris had no effect on the feeding of the other agent. Both agents reduced all the measured plant growth parameters equally, either singly or in combination (i.e. E. eichhorniae or M. scutellaris alone or together). The interaction between the two agents appears neutral and agents are likely to complement each other in the field. Prior feeding by E. eichhorniae or M. scutellaris on water hyacinth did not affect the subsequent feeding by either agent. Megamelus scutellaris prefers healthy fresh water hyacinth plants. In addition, planthoppers performed best in combination with the weevil, especially on plants with new weevil feeding scars. The results of the study showed that M. scutellaris is compatible with other biological control agents of water hyacinth that are already established in South Africa. Therefore, the introduction of M. scutellaris may enhance the biological control of water hyacinth in South Africa.
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Date Issued: 2018

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Synthesis and characterisation of novel platinum (II) complexes potential chemotherapeutic drugs

- Datt, Michael Steven

Authors: Datt, Michael Steven
Date: 2001
Subjects: Chemotherapy Platinum
Language: English
Type: Thesis , Doctoral , PhD
Identifier: vital:4366 , http://hdl.handle.net/10962/d1005031
Description: The present study involves the preparation of novel mixed-ligand platinum(II) complexes in the hope of expanding the range of platinum(II) complexes that exhibit anticancer activity and which are less toxic and have a broader spectrum of activity than cisplatin and its analogues. To this end, N-(3-R-benzoyl)-N’,N’-diethylthiourea, N-(3-R-benzoyl)-N’-morpholinothiourea, N-(3-Rbenzoyl)-N’,N’-di(2-hydroxyethyl)thiourea (R = NO2, Cl, H, CH3, OCH3), N,N-diethyl-N’-menthyloxycarbonylthiourea and N-menthyloxycarbonyl-N’-morpholinothiourea ligands, and their corresponding mixed-ligand platinum(II) complexes of the type [PtCl(L)(RR’SO)], were synthesised and characterised by elemental analyses, IR, 1H and 195Pt NMR spectroscopy and, in some cases, X-ray crystallography. Dimethylsulfoxide complexes were prepared using all the ligands, while complexes containing unsymmetrically substituted sulfoxides were prepared using the N-benzoyl-N’,N’-diethylthiourea and ,N-diethyl-’-(-)-(3R)-menthyloxycarbonylthiourea ligands only. The molecular structures of cis-(S,S)-[PtCl(DMSO)(L)] (where L = N-benzoyl-N’,N’-diethylthioureato, N-(+)-(3S)-menthyloxycarbonyl-N’-morpholinothioureato), cis-(S,S)-[Pt(N-benzoyl-N’,N’-diethylthioureato)Cl(MPSO)] and cis-[Pt(N-benzoyl-N’,N’-diethylthioureato)2] were determined by X-ray crystallography. The X-ray crystal structure of N,N-diethyl-N’- (-)-(3R)-menthyloxycarbonylthiourea was also determined. The spectroscopic and crystallographic data are consistent with complexes containing a (S,O)-chelated ligand and a sulfur-bonded sulfoxide ligand. However, the 1H and 195Pt NMR studies showed that the alkoxycarbonylthioureato complexes exist as geometric isomers with the sulfoxide coordinated either in a cis-(S,S) or trans-(S,S) arrangement with respect to the sulfur donor atom of the chelated ligand, whereas the acylthioureato complexes yielded only cis-(S,S)-[PtCl(L)(RR’SO)] complexes. The difference in the coordination chemistry of the acylthiourea and alkoxycarbonylthiourea ligands was examined further by treatment of the [PtCl(DMSO)(L)] complexes, where L = Nbenzoyl-N’,N’-diethylthioureato, N-benzoyl-N’-morpholinothioureato, N,N-diethyl-N’-(-)-(3R)- menthyloxycarbonylthioureato and N-(+)-(3S)-menthyloxycarbonyl-N’-morpholinothioureato, with PPh3 to give the corresponding [PtCl(L)(PPh3)] and [Pt(L)(PPh3)2]+ complexes. 31P NMR studies of these complexes reveal that the alkoxycarbonylthioureato ligands bind less strongly than the acylthioureato ligands, which is consistent with the crystallographic studies. The morpholine derivatives of the acylthioureato and alkoxycarbonylthioureato ligand systems also appear to bind less tightly than the diethyl derivatives. The weaker binding properties of the alkoxycarbonylthioureato ligands might be a possible explanation for the observed geometric isomerisation of these complexes, with the mechanism of isomerisation involving a chelate ringiv opening step. Furthermore, crystallographic and 31P NMR studies suggest that the acylthioureato carbonyl oxygen donor atom is relatively softer and therefore has a greater trans-influence than the carbonyl oxygen donor atom of the alkoxycarbonylthioureato ligand. The substitution kinetics of the chloride and sulfoxide leaving groups by azide, iodide, thiocyanate, triphenylphosphine, 2-mercaptobenzimidazole, 4-(dimethylamino)pyridine and thiourea, from selected cis-(S,S)-[PtCl(N,N-dialkyl-N’-(3-R-benzoyl)thioureato)(RR’SO)] complexes, in methanol, were evaluated to determine if variation of the electronic properties of the chelated ligand and variation of the sulfoxide have a significant influence on the reactivity of these complexes. Two consecutive reactions were observed. It was found that neutral nucleophiles initially substitute the dimethylsulfoxide, while anionic nucleophiles substituted the chloride ligand. For all the nucleophiles studied, the first substitution step was evaluated, except for triphenylphosphine and 4-(dimethylamino)pyridine, where the second step was also evaluated. The overall order of reactivity for the first substitution step was; N3 - < DMAP < I- < SCN- < MBI < thiourea < PPh3, with the rate varying three orders of magnitude. The substitution of the dimethylsulfoxide ligand by PPh3 from cis-(S,S)-[Pt(N-benzoyl-N’,N’-diethylthioureato)Cl-(DMSO)] to form cis-(S,P)-[Pt(N-benzoyl-N’,N’-diethylthioureato)Cl(PPh3)] was confirmed by X-ray crystallography. In general, manipulation of the chelating moiety, as well as interchanging the sulfoxide did not alter the reactivity of these complexes to a great extent. The anticancer activity of all the platinum(II) sulfoxide complexes were evaluated against a HeLa cell line, of which three complexes, cis-(S,S)-[PtCl(DMSO)(N,N-diethyl-N’-(3-nitrobenzoyl)- thioureato)], cis-(S,S)-[PtCl(DMSO)(N-morpholino-N’-(3-nitrorobenzoyl)thioureato)] and cis-(S,S)-[PtCl(DMSO)(N-(3-methoxybenzoyl)-N’-morpholinothioureato)] exhibited a concentration dependent anti-proliferative effect, but were less potent than cisplatin. These three complexes displayed a similar dose response in a MCF-7 cell line. Preliminary morphology studies with the three biologically active complexes in a HeLa cell line suggest that they induce cell death by apoptosis. Preliminary pBR322 plasmid DNA binding studies of selected [Pt(acylthioureato)Cl(RR’SO)]complexes clearly indicate that these complexes have a different mode of binding to DNA than cisplatin.
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Date Issued: 2001

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Phylogenetics and historical biogeography of the Teloganodidae (Ephemeroptera)

- Pereira da Conceicoa, Lyndall Louise

Authors: Pereira da Conceicoa, Lyndall Louise
Date: 2016
Language: English
Type: text , Thesis , Doctoral , PhD
Identifier: http://hdl.handle.net/10962/64900 , vital:28629
Description: The Teloganodidae are a mayfly family endemic to the southwestern Cape (South Africa), with relatives in Madagascar and Asia. Like many other aquatic invertebrates in Africa, they have been considerably understudied. Research into biodiversity and biogeography allows an understanding of the earth’s biota, producing knowledge which can be used to develop strategies to preserve and monitor this biota. Mismanagement of water systems places biodiversity of river fauna under an ever-increasing extinction threat. This investigation explores rivers in under-collected areas to determine how well teloganodids have been represented in the literature, with four genera and five species described at the onset of this study. A lectotype for Lestagella penicillata Barnard (1940) has been elected and described in detail, setting “benchmark” characters for future descriptions. Standard DNA sequencing methods provide portions of three mitochondrial genes; cytochrome oxidase subunit I (COI), small subunit ribosomal 16S RNA (16S), 12S ribosomal DNA (12S) and two nuclear genes, Histone 3 (H3) and 28S ribosomal DNA (28S) for up to 255 specimens. Fore and hind wings of 79 teloganodid adults were used to examine phylogenetic signal and evolutionary divergence using geometric morphometrics. A multi-faceted approach is used to investigate relationships between clades and the effects of deep-time climatic and landform changes which have influenced the diversity and distribution seen today. Tree (Bayesian Inference and Maximum Likelihood) and network (parsimony) phylogenies, ancestral reconstruction, historical biogeography and wingevolution of the Teloganodidae are investigated. Species tree analyses discovered 27 species and six genera. Distinct lineages are restricted to catchments, and strong phylogeographic structure was found within most genera. Southern African Teloganodidae are shown to have originated in the Cretaceous, with divergence and dispersal of lineages depended on their established locality at the time of tectonic events (uplift) and climatic changes (sea level regressions and transgressions). Geographic clines in wing-shape of Lestagella across its range imply evolutionary adaptations to specific catchment landscape and environment. A detailed analysis of biodiversity has many valuable contributions, from directing future research, understanding adaptive processes, fine-tuning phylogeographical and evolutionary hypotheses, to improving management and conservation decisions in order to preserve endemic biodiversity hotspots.
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Date Issued: 2016

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The social construction of "sexual knowledge": exploring the narratives of southern African youth of Indian descent in the context of HIV/AIDS

- Esat, Fazila

Authors: Esat, Fazila
Date: 2003
Subjects: East Indians -- South Africa -- Attitudes , Youth -- South Africa -- Attitudes , East Indians -- South Africa -- Sexual behavior , Youth -- South Africa -- Sexual behavior , AIDS (Disease) -- Social aspects -- South Africa , HIV infections -- Social aspects -- South Africa
Language: English
Type: Thesis , Masters , MA
Identifier: vital:2970 , http://hdl.handle.net/10962/d1002479 , East Indians -- South Africa -- Attitudes , Youth -- South Africa -- Attitudes , East Indians -- South Africa -- Sexual behavior , Youth -- South Africa -- Sexual behavior , AIDS (Disease) -- Social aspects -- South Africa , HIV infections -- Social aspects -- South Africa
Description: This study pays attention to youth of Indian-descent within the context of sexuality and identity and their role in HIV/AIDS. By gaining an understanding of this interaction between identity and sexuality, it adds to our knowledge of the social dynamics that contribute to the prevalence or lack of prevalence of HIV/AIDS within population groups. This study uses a social constructionist discourse analytic framework and aims to explore the construction of sexual knowledge by Southern African youth of Indian-descent. The findings indicate that the construction of sex is primarily one of risk and ambiguity. Additionally, the construction of sexual knowledge highlights the significance of gender differentials and the importance of agency and responsibility for sexual education. These constructions reinforce traditional educational roles that contribute to the construction of sex as risky and ambiguous. In addition, a social identity of Indian-ness and othering is used as a strategy to give meaning to the lack of parental responsibility with regard to sexual education. The use of social identity is seen as highlighting the importance of acknowledging the sexual values within which youth are embedded. This study concludes with possible ways to shift these constructions. For example, one of the conclusions suggests the implementation of an alternative school-based sexual education that acknowledges the sexual values in which youth are embedded. Furthermore, this acknowledgement of sexual values should take place within a holistic sex education programme that is positive about sexuality. Additionally, a reframing of youth as capable and active decision-makers in their sexual education is necessitated in order to see youth as a potential resource in HIV/AIDS prevention.
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Date Issued: 2003

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