An investigation into the interaction effects of simultaneous physical and cognitive task execution on performance, perceptual and physical responses
- Authors: Ross, Natalie
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/3562 , vital:20525
- Description: Many modern day work environments require some degree of dual tasking, particularly the simultaneous performance of cognitive jobs alongside physical activity. The nature of such tasks is often job dependent and may require cognitive functions such as perception, decision making, memory, or response selection/execution in conjunction to task specific physical requirements. Previous research has indicated a possible relationship between concurrent physical and cognitive demands and task performance, safety and efficiency. However, this research is limited and inconsistent. The current study aimed to identify the interaction, if any, between concurrent physical and mental demands, and determine the impact of sensory modality and stage of information processing on this interaction, with specific focus on the performance, perceptual and physical responses during different types of cognitive tasks performed concurrently with a lifting task. 20 (10 male, 10 female) Rhodes University students participated in this study. Each participant performed 9 test conditions - a physical lifting task, a visual and an auditory memory task, and a visual and an auditory decision making task in isolation, as well as the lifting task concurrently with each of these cognitive tasks. Performance was recorded via accuracy and work output of cognitive tasks and the number of lifts for each condition. Perceptual measures were obtained via the Borg RPE and Subjective Workload Assessment Technique. Spinal kinematics were measured using the Lumbar Motion Monitor, while muscle activity of the Erector Spinae, Rectus Abdominis, Rectus Femoris and Biceps Femoris muscles were recorded using the Biometrix Data Logger surface EMG equipment. Mean results were analysed using a dependent T-test to observe any general interaction, and a Two-way ANOVA for the impact of sensory modality and stage of processing. Individual responses were also considered to gain better understanding of both intra and inter-human variability under the various test conditions. Results showed a significant decrease in cognitive performance, increased perception of physical effort, time pressure, mental effort and psychological stress under simultaneous physical and mental demands, while no significant differences in physical responses were observed. Further observations included increased dual-task interference during visual and decision-making tasks when combined with physical demands compared to that of auditory and memory tasks respectively. Individual responses showed large variability between individuals indicating the presence of positive, negative and non-responders to concurrent physical and mental demands. Results therefore imply an individual specific interaction between concurrent physical and mental demands that may or may not be detrimental to worker productivity, job error, injury rates and worker well-being, and that the type of cognitive task performed may impact this interaction.
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Landscapes of division: social movements and the politics of urban and rural space in the Grahamstown region of the Eastern Cape
- Authors: O’Halloran, Paddy
- Date: 2016
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/3950 , vital:20572
- Description: This thesis investigates the politics of two grassroots social movements, the Unemployed People’s Movement (UPM), based in Grahamstown, and the Rural People’s Movement (RPM), based in the rural areas near Peddie, forty miles east. Observing that urban and rural are political designations, the primary question of this thesis is: Do the politics of these social movements challenge the conception of urban and rural as discrete political spaces? To some extent, it responds to and complicates Mamdani’s theory of a bifurcated state in post-apartheid South Africa in which urban zones are the site of civil society and rural zones the site of traditional authorities, and only the former a democratised space (1996). Three themes—race, space, and citizenship—are employed and interrogated in the process of answering the principal question. Broadly historical in nature, and understanding the present political context to be a product of historical processes, the thesis begins with an historical study of the Grahamstown region from the time of the town’s founding in 1812 until the end of apartheid in 1994, keeping the three key themes in focus. Then the politics of UPM and RPM are explored through a series of interviews aimed at understanding the context and experience of movement members and seeking their insight into the question of urban and rural space. Their responses are presented as a dialogue employing a theoretical strategy from Aguilar (2014) that distinguishes between and provides a framework to measure the ‘practical scope’ and the ‘interior horizon’ of movements. The thesis concludes with a discussion of important themes arising in the interviews: citizenship, NGOs, and political parties, and, of course, space. The backdrop to this concluding discussion is the xenophobic violence which occurred in Grahamstown in October 2015, helping situate the research and themes within the broader context of South African politics.
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Female identity in the post-millennial Nigerian novel: a study of Adichie, Atta, and Unigwe
- Authors: Wambui, Mary Theru
- Date: 2015
- Subjects: Adichie, Chimamanda Ngozi, 1977- -- Criticism and interpretation , Adichie, Chimamanda Ngozi, 1977-. Purple hibiscus , Atta, Sefi -- Criticism and interpretation , Atta, Sefi -- Everything good will come , Unigwe, Chika. Criticism and interpretation , Unigwe, Chika. Fata Morgana -- English , Nigerian fiction -- History and criticism , Women -- Identity , Women in literature , Feminism in literature
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2330 , http://hdl.handle.net/10962/d1020013
- Description: This thesis project examines the work of three female Nigerian authors: Chimamanda Ngozi Adichie, Sefi Atta and Chika Unigwe. They are part of a growing number of young African writers who are receiving international acclaim and challenging narratives that have long defined the continent in pejorative terms. They question what it means to be female and African in a transcultural, global world but counter discourses that are both restrictive and prescriptive. Their female characters are not imaged in binary terms as either victims or villains. For all three writers, the African story has to be told in its entirety incorporating what some may argue are negative stereotypes but doing so in a manner that examines and undermines those same stereotypes. For the purposes of the thesis, I focus on their first novels: Adichie’s Purple Hibiscus, Atta’s Everything Good Will Come and Unigwe’s On Black Sisters’ Street. Chapter One examines Purple Hibiscus and argues that the novel is much more than a coming of age story or, as some critics have posited, an allegory of the postcolonial state. Chapter Two highlights Atta’s use of fairly familiar feminist theories but grounds them in the lived realities of the African city. All three authors are concerned with issues of violence and death. Unigwe’s novel, which forms the focus of Chapter Three, offers a critical perspective on how both of those themes intersect with the increasing commercialisation of global culture. Her characters are female sex workers whose lives are irrevocably altered by the murder of one of their colleagues. I conclude by arguing that the three novels offer a nuanced if not necessarily new understanding of the various social, economic and political forces that continue to shape the lives of women on the continent.
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Understanding how students' relationships with their cellphones inform their experience of social participation online and offline
- Authors: Oosthuizen, Jess
- Date: 2015
- Subjects: Cell phones -- South Africa -- Psychological aspects , Social participation , Cell phones -- South Africa -- Social aspects , College students -- South Africa , Social media addiction
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3264 , http://hdl.handle.net/10962/d1017887
- Description: The pervasive presence of cellphones in the lives of urban young people around the globe has led to widespread research to evaluate the impact that this device has on young people’s overall psychosocial development. This relationship is often characterised as “addictive”. This research study presents a unique South African youth perspective in a field of research that is predominantly conducted in the United States, Europe and Asia. It explores the relationship that students (ages 18–21) at Rhodes University have with their cellphones in order to understand how this device informs their experience of social participation online and offline. Central to the design of this study is a “social media detox” which involved the research participants volunteering to restrict their social media and cellphone use for an agreed-upon period of time. The study employs interpretative phenomenological analysis (IPA) to uncover key themes from in-depth interviews before and after the detox. Eight respondents were interviewed twice; once before and once after their detox. This study provides insights into the integral role of a cellphone as reported from a young adult’s perspective. Communicating on social media platforms using a cellphone has become normalised among this age-group and the respondents described how the cellphone feels like “a part of you”. Unlike interacting face-to-face which is potentially awkward and involves effort, socialising on a cellphone offers the respondents a sense of companionship, control and instant access to their peer groups. The respondents in this study seemed unaware of their own agency in social situations until their participation in the social media detox. By participating in this study, the participants became more aware of how their cellphone use influences social behaviour, both online and offline. The study proposes that the term “addiction” undermines the positive association young people have with their cellphones. Instead, this study suggests that “social fitness” would be a more relevant construct through which to encourage and support young people to exercise agency in their social lives. This exploratory study raises new questions for researchers, programme developers and educators to take up in future studies and programme development
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Understanding how trainee teachers engage with prior everyday knowledge and experience associated with biological concepts during integrated natural science education 5-7 : a case study
- Authors: Enghono, Albertina Magano
- Date: 2014
- Subjects: Biology teachers -- Training of -- Namibia -- Case studies Teacher educators -- Training of -- Case studies Teachers -- Training of -- Namibia -- Case studies Education -- Namibia -- Case studies Prior learning -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1970 , http://hdl.handle.net/10962/d1011972
- Description: Since the Namibian independence in 1990, the education system has undergone some major revamping which involved the adoption of social constructivist perspectives in the teaching and learning of sciences. This learning theory acknowledges learners’ background prior knowledge as valuable tools in the effective construction of science concepts during lessons. A corollary is that the socio-cultural circumstances of learners might negatively influence the way learners construct new knowledge in the science classroom if they are not taken into consideration. This study was thus prompted by the need to understand how trainee science teachers engage with prior everyday knowledge and experiences, so as to enhance the conceptual development of biological concepts. The study was qualitative and it was underpinned by an interpretive paradigm with some elements of action research. Science trainee teachers at Katima Mulilo, Unam Campus were used as research participants. The techniques used to gather data included document analysis, brainstorming, observation, audio-visual, microteaching and semi-structured interviews. The results of this study showed that the changes that occurred during microteaching practices of the four trainee teachers involved in the study reflected their professional development in this approach. However, it emerged that prior everyday knowledge can be both a barrier and enabler to the construction of meaningful teaching and learning; hence its oversight may lead to instructional failures. The findings also indicated that selected platforms are essential to enable trainee teachers to incorporate prior everyday knowledge and experiences into the teaching of Western science. However, larger scale study should be conducted in order to deepen the understanding of the topic.
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Integrating spirituality and psychotherapy : experiences of a sample of terminally ill patients
- Authors: Chemane, Bonginkosi Reginald
- Date: 2013-07-15
- Subjects: Psychotherapy Terminal care -- South Africa -- Grahamstown Hospices (Terminal care) Terminally ill -- Psychology Spiritual care (Medical care)
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3183 , http://hdl.handle.net/10962/d1008217
- Description: The general aim of this study was to determine the experiences of a sample of terminally ill patients in using spiritually focused psychotherapy. This was a qualitative study conducted to a sample of 2 terminally ill patients from hospice in Grahamstown, South Africa. The research was conducted in 3 phases: an initial in-depth interview conducted to determine the participants' level of spirituality as well as the extent to which their terminal illnesses had affected their functioning. This was followed by a minimum of 6 spiritually focused therapy (SFT) sessions as a second phase of the research. To determine the participants' experiences of SFT, 2-3 in-depth interviews were conducted during the 3m phase of the research study. The research revealed that a belief in a higher power helps terminally ill patients cope better with their illness and that social disconnectedness is related to HIV / AIDS stigma. It also revealed that terminal illness is co-morbid with other psychiatric symptoms such as depression, evokes existential concerns, results in a change in the level of spirituality and affects the whole family. Participants blamed themselves for their illness, but found that engaging in the process of forgiveness of self and others brought about psychological healing for them. They experienced SFT as a coping resource that assisted them to deal with the fear of death as well as increased insight into the development of psychopathology and spiritual blockages. It is recommended that a comprehensive and holistic assessment during intake be undertaken so that where spiritual needs are available, therapy can be spiritually augmented to ensure that such needs/ struggles are addressed. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
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'I want to tell the story again': re-telling in selected novels by Jeanette Winterson and Alan Warner
- Authors: Collett, Jenna Lara
- Date: 2011
- Subjects: Warner, Alan Criticism and interpretation Winterson, Jeanette, 1959- -- Criticism and interpretation English fiction -- 20th century -- History and criticism
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2248 , http://hdl.handle.net/10962/d1002291
- Description: This thesis investigates acts of ‘re-telling’ in four selected novels by Jeanette Winterson and Alan Warner.Re-telling, as I have defined it, refers to the re-imagining and re-writing of existing narratives from mythology, fairy tale, and folktale, as well as the re-visioning of scientific discourses and historiography. I argue that this re-telling is representative of a contemporary cultural phenomenon, and is evidence of a postmodern genre that some literary theorists have termed re-visionary fiction. Despite the prevalent re-telling of canonical stories throughout literary history, there is much evidence for the emergence of a specifically contemporary trend of re-visionary literature. Part One of this thesis comprises two chapters which deal with Winterson’s Sexing the Cherry (1989) and Weight (2005) respectively. In these chapters, I argue that, although the feminist and historiographic elements of her work are significant, there exist further motivations for Winterson’s acts of re-telling in both Sexing the Cherry and Weight. In Chapter One, I analyse Winterson’s subversion and re-imagining of historiography, as well as her re-telling of fairy tale, in Sexing the Cherry. Chapter Two provides a discussion of Winterson’s re-telling of the myth of Atlas from Greek mythology, in which she draws on the discourses of science, technology, and autobiography, in Weight. Part Two focuses on Warner’s first two novels, Morvern Callar (1995) and These Demented Lands (1997). In both novels, Warner re-imagines aspects of Christian, Celtic and pagan mythology in order to debunk the validity of biblical archetypes and narratives in a contemporary working-class setting, as well as to endow his protagonist with goddess-like or mythical sensibilities. Chapter Three deals predominantly with Warner’s use of language, which I argue is central to his blending of mythological and contemporary content, while Chapter Four analyses his use of myth in these two novels. This thesis argues that while both Winterson and Warner share many of the aims associated with contemporary re-visionary fiction, their novels also exceed the boundaries of the genre in various ways. Winterson and Warner may, therefore, represent a new class of re-visionary writers, whose aim is not solely to subvert the pre-text but to draw on its generic discourses and thematic conventions in order to demonstrate the generic and discursive possibilities inherent in the act of re-telling.
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Biological control of Pereskia aculeata Miller (Cactaceae)
- Authors: Paterson, Iain Douglas
- Date: 2011
- Subjects: Pereskia -- Biological control -- South Africa Cactus -- Biological control -- South Africa Invasive plants -- Biological control -- South Africa Curculionidae -- South Africa Pyralidae -- South Africa Insects as biological pest control agents -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5825 , http://hdl.handle.net/10962/d1007653
- Description: Pereskia aculeata Miller (Cactaceae) is an environmental weed that is damaging to natural ecosystems in South Africa. The plant is native to Central and South America and was first recorded in South Africa in a botanical garden in 1858. In this thesis, research into the biological control of P. aculeata was conducted with the intention of improving the control of the weed. A pre-release study of the relationship between P. aculeata density and native plant biodiversity indicated that P. aculeata has a negative impact on native biodiversity. The native plant biodiversity associated with different P. aculeata densities was used to determine threshold values and goals for the control of the weed. A threshold value of 50% P. aculeata density was calculated, indicating that P. aculeata density must be maintained below 50% in order to conserve native plant biodiversity. The ultimate goal of the control programme should be to maintain P. aculeata densities below 30%. At these densities there was no significant difference in native plant biodiversity from if the weed were absent from the ecosystem. The biological control agent, Phenrica guérini Bechyne (Chrysomelidae), has been released in South Africa but the potential of the agent to impact P. aculeata is not known and no post release evaluation has been conducted. Impact assessment studies indicate that P. guérini does not impact P. aculeata, even at high densities, but the results of greenhouse experiments should be interpreted with caution because of problems with extrapolation into the field. Although observations in the field suggest that P. guérini has reduced P. aculeata densities at one site, it is clear that new biological control agents are needed to reduce the weed to acceptable levels. Identifying the origin of the South African P. aculeata population was believed to be important to the biological control programme due to the disjunct native distribution and intraspecific variation of the species. Natural enemies associated with plant genotypes in different parts of the native distribution may have developed specialised relationships with certain intraspecific variants of the plant, resulting in differences in agent efficacy on certain host plant genotypes. A molecular study indicated that the closest relatives to the South African weed population found in the native distribution were in Rio de Janeiro Province, Brazil. A bioassay experiment in which fitness related traits of the biological control agent, P. guérini, were measured on various P. aculeata genotypes was conducted to determine the importance of host plant intraspecific variation. There was little variation in fitness traits between genotypes and no evidence of intraspecific host plant specialization. Although intraspecific variation had no effect on agent efficacy in the case of P. guérini, it is possible that other natural enemies may be more specialized. Genotype matching is expected to be more important when natural enemies likely to be specialised to individual genotypes are considered for biological control. Potential biological control agents were prioritized from data collected on surveys in the native distribution. The most promising of these, based on the presence of feeding, incidence, predicted host range, climatic matching, genotype matching and mode of damage, are two species of Curculionidae, the current biological control agent P. guérini and the stem boring moth, Maracayia chiorisalis Walker (Crambidae). The two curculionid species and M. chlorisalis should be considered priorities for host specificity studies. Releases of P. guérini and any new biological control agents should be made at sites where the pre-release study was conducted so that post-release evaluation data can be compared with the pre-release data and the impact of biological control can be evaluated. Retrospective analyses of biological control programmes provide important ways of improving aspects of biological control programmes, such as methods of agent selection. The evaluation of success in biological control programmes is essential for retrospective analyses because factors that have lead to successes or failures can be analysed. Retrospective analyses of biological control programmes, such as this thesis, may improve weed management, thereby contributing to the conservation of natural resources.
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Creating a relationship: a discourse analysis focusing on the construction of identities and relationships in distance education materials for a teacher upgrade programme
- Authors: Van der Mescht, Caroline
- Date: 2005
- Subjects: Distance education -- South Africa Teachers -- Training of -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1467 , http://hdl.handle.net/10962/d1003348
- Description: Distance education, and therefore the writing of distance materials, is a growing field in South Africa. This makes it potentially a site of innovation and change as writers experiment with ways of creating effective teaching situations at long range. The Fort Hare Distance Education Project materials seem to be a response to both the increased need for teacher upgrade programmes and the need for innovation to tailor those programmes to the needs of local teachers in a changing society. This innovative attempt to communicate with tertiary distance students has unusual features which suggest that they are worth investigation. Using discourse analysis, including the work of Scollon and Scollon on politeness theory, and an analysis of visual elements using categories developed by Kress and van Leeuwen, this study focuses on 18 pages of a sample text, booklet 9, “A Whole Language Approach,” to investigate how the writer-reader relationship and the identity of the reader are constructed. The analysis reveals a complex, interlocking construction of identity and relationship, producing and resolving apparent contradictions as writers move from one position to another while they negotiate their ongoing and evolving relationship with the readers. Features of identity and relationship operating through the text include issues of authority, changing roles of teachers and learners, trust, what constitutes appropriate language and materials, acknowledging prior learning in under-qualified professionals, ownership of the text, hierarchy and egalitarianism, and stereotyping. The study suggests that the Fort Hare Distance Project materials offer an example of strategies suited to local students which should benefit those who design such courses. It further suggests that visual analysis together with discourse analysis provides insights which seem not to be accessible through a study of the verbal text, and that an analysis of visual elements may widen a researcher’s options. It reveals ways in which writers can negotiate conflicting positions and consciously or unconsciously attempt to resolve contradictions and ambivalence. It suggests issues which need to be negotiated in any text written in South Africa for a similar audience.
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Equity in the South African legal system a critical ethnography
- Authors: Leiper, Jonathan
- Date: 2004
- Subjects: Court interpreting and translating -- South Africa , Language and languages -- Law and legislation -- South Africa , Translators -- Training of -- South Africa , Translators -- Legal status, laws, etc. -- South Africa , Law -- Translating -- South Africa , Law -- South Africa -- Language
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2355 , http://hdl.handle.net/10962/d1002637 , Court interpreting and translating -- South Africa , Language and languages -- Law and legislation -- South Africa , Translators -- Training of -- South Africa , Translators -- Legal status, laws, etc. -- South Africa , Law -- Translating -- South Africa , Law -- South Africa -- Language
- Description: This thesis focuses on the process of interpreting and the difficulties faced by interpreters in the Magistrates' Court in Grahamstown, South Africa. More particularly, the thesis seeks to establish whether the constitutional guarantee of language equity can be applied to the courts - given the numerous problems with interpreting. Respondents from different spheres of the legal profession were interviewed in order to ascertain their perspectives on the state of interpreting, problems that are encountered by interpreters and attitudes displayed by other members of the legal profession towards interpreters. The methodology used in the thesis is that of a critical ethnography. As such, the research also has a critical focus, seeking to determine the ideologies and interests of different ):articipants in the legal process. On the basis of the data collected, a number of conclusions are drawn. The first is that interpreting in South Africa is in trouble. The system of interpreting is beset by a number of different problems. This study describes four different types of problems that are faced by interpreters: linguistic problems, environmental problems, training and administrative issues, and poor status in the eyes of the other participants in the legal process. Together the cumulative effect of these problems is the undermining of the principle of equity in the justice system. Finally, the thesis provides various practical and achievable solutions to the problems outlined above, specifically those faced by interpreters. The researcher also critically evaluates the efforts and motives of the Department of Justice and Constitutional Development.
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Law and culture in the new constitutional dispensation with specific reference to the custom of circumcision as practiced in the Eastern Cape
- Authors: Momoti, Ndyebo Kingsworth
- Date: 2004
- Subjects: Xhosa (African people) -- Social life and customs Xhosa (African people) -- Rites and ceremonies Circumcision -- Law and legislation -- South Africa -- Eastern Cape Initiation rites -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:3685 , http://hdl.handle.net/10962/d1003200
- Description: This study examines the custom of circumcision in the context of culture, law and the Constitution. In Chapter 1 the writer considers the pervasive role of culture in the context of the current debate in relation to equality versus culture. In Chapter 2 the writer considers the origin, development and the legal significance of the custom of circumcision in the Eastern Cape. In Chapter 3 the writer traces the circumstances leading to the enactment of the Provincial statute governing circumcision of children. In this chapter the writer also poses the question whether an aspect of morality can effectively be regulated by law. Chapter 4 looks at the question of cultural rights in terms of the Constitution and the possible effect of the promulgation of the Commission for the Promotion and Protection of the Rights of Cultural, Religious and Linguistic Communities Act 19 of 2000 on the approach of the courts in respect of constitutional challenges directed at some aspects of customary law. Chapter 5 looks at the custom of circumcision and the need for the protection of children. The writer raises the issue of the role of traditional leaders in the eradication of abuses associated with circumcision. The last Chapter comments on the reasons for the failure of the new Act governing circumcision in the Province.
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An economic analysis of eradicating alien vegetation as an alternative to conventional water supply schemes: a case study of the Krom and Kouga
- Authors: Carpenter, Robert Charles
- Date: 1999
- Subjects: Alien plants -- South Africa , Water-supply -- South Africa , Kouga River (South Africa)
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1000 , http://hdl.handle.net/10962/d1002735 , Alien plants -- South Africa , Water-supply -- South Africa , Kouga River (South Africa)
- Description: South Africa is classified as an arid to semi-arid region and water scarcity in South Africa has been identified as a key factor limiting socioeconomic development in the next century. In the Algoa region, the total urban plus agricultural water demand is expected to exceed the supply by the year 2005. The Kouga Working for Water Project aims to increase the base flow to the existing dams which supply the Port Elizabeth metropolitan area through the eradication of invasive alien trees in the riparian areas of the Krom and Kouga catchments. This thesis analyses the economic efficiency of optimal catchment management as a water supply scheme. A cost-benefit analysis is conducted for the Kouga eradication programme, and its desirability is evaluated in terms of the net present value (NPV) and the internal rate of return (IRR) criteria. In order to compare the cost-e~i.ciency of the eradication programme to alternative water supply augmentation schemes the Unit Reference Value (URV) is calculated for the project. The NPV for the project is calculated using a discount rate of 7% and amounts to nearly R24 million. This positive NPV indicates that the project is economically desirable in that it results in the improvement of human welfare. The IRR decision rule supports this finding. The URV of the eradication scheme is found to be competitive to that generated by more conventional schemes. Considered in the evaluation of the project are a host of environmental benefits that accompany the eradication of alien vegetation. This is in contrast to alternative schemes which result in several detrimental impacts to the environment. The economic analysis concludes that the eradication of alien vegetation is an efficient and desirable alternative water supply augmentation scheme. The conclusions drawn from the analysis of the eradication programme in this catchment area can be extended to other catchment areas, with the aim of promoting the most efficient supply of water.
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Isolation and identification of Beta-Lactam Producing Microorganisms using PCR based methodologies
- Authors: Krallis, Myrsini
- Date: 1997
- Subjects: Polymerase chain reaction , Bacterial genetics , Fungi -- Genetics , Beta lactam antibiotics , Microbial enzymes
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4155 , http://hdl.handle.net/10962/d1018237
- Description: The polymerase chain reaction (PCR) was investigated as a potential tool in microbial screening for 13-lactam. producing organisms. Optimization of PCR conditions and the addition of acetamide to the PCR reaction allowed for the successful amplification of the isopenicillin N synthetase (lPNS) gene in S. clavuligerus, S. tanashiensis, S. griseus, S. olivaceus, S. lipmanii, and S. chartreusis. PCR was used to produce a radiolabelled probe from S. clavuligerus that was used to detect analogous genes in bacteria and fungi. Southern blot and dot blot analysis using the lPNS probe revealed the presence of IPNS-like sequences in seventeen organisms. Fourteen of these sequences belonged to known 13-lactam. producing organisms; one unidentified soil isolate; and two non-/3-lactam. producing organisms viz. S. venezuelae ATCC 10712 and S. hygroscopicus ATCC 21703. The lPNS gene was also detected in a 13-lactam producer (S. chartreusis) that had lost its ability to produce antibiotic. It would therefore have been overlooked in a conventional antibiotic screening program. The use of PCR, coupled with Southern hybridization and dot blot analysis, increased the sensitivity and specificity of the antibiotic screening procedures and allowed for the investigation of evolutionary relationships between the eukaryotes and the prokaryotes. A preliminary investigation into the potential use of RAPD PCR and protein fmgerprinting as tools for solving discrepancies in streptomycete identification was conducted. A variety of streptomycete species that were chosen as being representative of a number of numerical taxonomic classes were amplified using various RAPD primers. Streptomycetes appear to be genetically diverse organisms as was reflected by their RAPD and protein profiles. The application of PCR in an antibiotic screening program showed great potential as a specific and sensitive tool in the detection of /3-lactam producers and in the elimination of duplicate strains.
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An examination of the suitability of some contemporary South African fiction for readers in the post-developmental reading stage
- Authors: Cole, Lorna
- Date: 1992
- Subjects: Children's literature, South African -- History and criticism Children -- Books and reading -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1530 , http://hdl.handle.net/10962/d1003412
- Description: Adverse criticism regarding the quantity and quality of children's books in South Africa appear in such respected sources as The Oxford Companion to Children's Literature and The Companion to South African English Literature, the authors of which are of the opinion that South African children are dependent solely upon Eurocentric literature for their reading material. In recent years however, local publishers have attempted to redress this imbalance by offering prizes for unpublished works. These prizes have acted as incentives for aspiring writers, many of whom have had novels published specifically for children in the post-developmental reading stage. This study critically examines some of these prizewinning works of fantasy and contemporary realism, in an effort to gauge their literary worth within the context of accepted criteria for judging children's literature. Accolades from adults are not however a guarantee that the prizewinning books will be received with equal acclaim by the children for whom they are written. For this reason, five children in the post-developmental reading stage were asked to pass their opinions and non-literary judgments on the books. Although the critical evaluation of the indigenous works proves them to be eminently worthy of the prizes which they received on publication, the children did not rate them as highly as certain imported works. The works of fantasy by Marguerite Poland rated poorly in terms of their popularity despite the fact that the children said that in a non-circumscribed context, they choose fantasy in preference to contemporary realism. Within the context of the indigenous literature which they read for this study though, they preferred the works of contemporary realism as they were able to identify with particular aspects of the novels. Indigenous literature for children in the post-developmental reading stage is a comparatively new phenomenon which needs to be nurtured if it is to attain any lasting status. The onus rests upon the teachers of literature and librarians to introduce the literature and make the books more accessible to young readers. Publishers need perhaps to engage the views and opinions of the audience for whom the books are written in an effort to publish books which, without in any way detracting from their literary worth, will deal with subjects favoured by young readers.
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The taxonomy and life history of the blue stingray, Dasyatis marmorata capensis (Batoidea : Dasyatidae) from Southern Africa
- Authors: Cowley, Paul D (Paul Denfer), 1964-
- Date: 1990
- Subjects: Stingrays -- Africa, Southern Dasyatidae
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5183 , http://hdl.handle.net/10962/d1001959
- Description: The blue stingray, Dasyatis marmorata capensis is an important recreational shore angling species, especially amongst tournament anglers, in South Africa. The taxonomy and aspects of the biology of this species were investigated from specimens collected between March 1987 and May 1989, from various localities along the southern African coastline. Morphological comparisons were made between Dasyatis pastinaca, Dasyatis marmorata and the local variety. The results indicated that the local variety is different to D. pastinaca in colouration, disc length size, and vertebral and radial counts. The proposed new sub-species Dasyatis marmorata capensis is closest to Dasyatis marmorata of the north-eastern Atlantic coast, but differs in snout angle, disc length and snout to vent length. Analysis of catch per unit of effort data revealed that the blue stingray exhibits distinct seasonality. Adult and sub-adult fish undertake an annual onshore/offshore migration and invade the inshore region between spring and summer, while juveniles remain offshore and utilize this zone as a nursery area. Length-at-age and growth rates for both sexes were estimated from bands formed seasonally in the vertebral centra. The derived von Bertalanffy growth parameters indicated that females reach a greater asymptotic size (913.8 mm DW) and have a slower growth rate (K = -0.07) than males (531.8 mm DW, K = -0.17). Growth rates of juvenile captive specimens compared favourably with back calculated values, at approximately 65 mm/year, for the first year of growth. Dasyatis marmorata capensis is an aplacental viviparous elasmobranch with a well defined annual breeding cycle. Young are released , at a size of 170-200 mm DW, from October to December after a gestation period of approximately nine months. An average fecundity of 3.07 was calculated . Examination of gonadal development indicated that sexual maturity is first attained at a size of 408 and 500 mm DW in males and females, respectively, corresponding to ages 4.5 and 7 years. Size-related food habits were determined independently from three depth zones. The major prey items for each size class were directly related to the abundance of the infauna of the different depth zones. Polychaeta, amphipoda and stomatopoda were the major prey items in the offshore zone. In the nearshore zone, the dominant prey species were Balanoglossus capensis and Callianassa spp .. The high incidence of empty stomachs and the presence of prey items which occur in greatest abundance beyond the surf zone indicated that this zone is not utilized for the purposes of feeding.
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Some aspects of the reproductive endocrinology of the catfish, Clarias Gariepinus (Burchell, 1822)
- Authors: Rennie, Susan Elizabeth
- Date: 1981
- Subjects: Catfishes Clarias gariepinus
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5339 , http://hdl.handle.net/10962/d1005924
- Description: A description is given of the location, anatomy and morphology of the endocrine glands likely to be involved in controlling the reproductive cycle of C. gariepinus. Methods of identifying the secretory tissues in the light and electron microscopes are outlined. A review of the published results on homologous tissues from other teleosts is included and directions for further research on the endocrinology of C. gariepinus are discussed.
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Some properties of magnetospheric electrons observed west of Sanae
- Authors: Greener, James G
- Date: 1973
- Subjects: Magnetosphere
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5523 , http://hdl.handle.net/10962/d1012091 , Magnetosphere
- Description: The southern hemisphere has always been the neglected twin in the field ot geophysical research. The reasons for this are certainly not in the realm of science but in the history of man and his development in the northern half of the globe. Geophysically, however, our southern half provides a wealth of interesting problems and anomalies. Roederer (1966) explains the use of this word 'anomaly' by showing what some of the oddities of the southern hemisphere are, and by contrasting them with the corresponding regions of the earth across the equator. The principal feature is of course the geomagnetic surface field strength minimum at a point in the South Atlantic ocean very near the coast of Brazil. Intro., p. 1.
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A comparison of attitudes toward intensive competition among high school pupils
- Authors: Potgieter, Justus R
- Date: 1971
- Subjects: Competition (Psychology) in adolescence Competition (Psychology) Interpersonal relations Motivation (Psychology)
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1930 , http://hdl.handle.net/10962/d1007604
- Description: From Preface: As a teacher with experience in competitive sport, the author became interested in the topic of athletic competition when joining the staff of an all-boys' school. The competitive aspect of sport at such a school can make quite an impression on an inexperienced teacher. The question then arose; Is this competitive atmosphere universal? Is this type of competition acceptable and desirable in our schools? Being a teacher of Physical Education as well as other subjects and also being actively involved in the coaching of senior sports teams the author regarded himself suitably qualified to investigate the matter of athletic competition in our schools.
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The anatomy of human misery and its therapy : a study of miracles and healing in the life of our Lord and in the early church, until the Council of Nicaea
- Authors: Hawkridge, John Bernard
- Date: 1959
- Subjects: Jesus Christ -- Miracles , Spiritual healing -- Psychological aspects , Healing in the Bible , Church history
- Language: English
- Type: Thesis , Bachelor , BDiv
- Identifier: vital:1257 , http://hdl.handle.net/10962/d1012229 , Jesus Christ -- Miracles , Spiritual healing -- Psychological aspects , Healing in the Bible , Church history
- Description: This thesis seeks to show that miracles and healing are inseparable from the Messianic task of Jesus Christ; and that in so far as He commissioned His Church to continue that Messianic task, it is reasonable to expect that miracles and healing would continue. The early history of the Church is examined for evidence confirming this expectation, and a question is asked of the contemporary Church.
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The atonement : a brief discussion
- Authors: Hay, Thomas Alexander
- Date: 1958
- Subjects: Atonement , Satisfaction for sin
- Language: English
- Type: Thesis , Bachelor , BDiv
- Identifier: vital:1258 , http://hdl.handle.net/10962/d1012233 , Atonement , Satisfaction for sin
- Description: This first section endeavours briefly to set out the problem, seeing it ln its proper context against the need it fulfils and its historical setting. It attempts to show something of the nature of sin and the need which sin creates; and asks the question Why Atonement? This question can only be answered by an appreciation of the meaning and power of sinfulness. Atonement is necessarily from God's side, and it is costly to God. An important factor in this section is the attempt to see the wholeness of Christ's work; to set the atonement in its true context within the life of Christ. An attempt is made to relate the atonement to the incarnation, The Word made flesh and dwelling among us; to the resurrection, which is not to be misunderstood as a mere evidential appendage to the cross, but to be seen as an essential factor in the salvation of men; and also to the ascension, to the problem of time and eternity, in that while Christ's work was once-for-all, it is nevertheless continued - it was in history, but is not bound within history. When this conception of the unity of Christ's work is grasped then we can turn to a consideration of the cross, always regarded by Faith as the very centre of the atonement. A brief survey is made of the Biblical teaching concerning salvation and the cross; and the centrality of the cross is interpreted sacrificially. Summary, p. x-xi.
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