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An investigation into the potential immunogenicity of various extracts of the South African bont tick Amblyomma hebraeum

  • Authors: Adamson, Deborah Jane
  • Date: 1993
  • Subjects: Amblyomma -- South Africa , Ticks -- South Africa , Ticks -- Control -- South Africa
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4127 , http://hdl.handle.net/10962/d1015640
  • Description: Rabbits and goats were inoculated with crude, membrane-associated and soluble components extracted from unengorged adult females and nymphs of the bont tick Amblyomma hebraeum. Inoculation provided some protection against nymphal infestation, however it had little effect on adult feeding. Histological examination of adults fed on inoculated hosts showed evidence of gut damage. Skin provocation testing with tick extracts elicited a Type I immediate hypersensitivity which was influenced by antihistamine. A delayed skin reaction was also evident. Whether this was attributable to Type III Arthus reaction or Type IV cell-mediated hypersensitivity was not determined. A comparative histological study of sites of tick extract injection, on inoculated and naive hosts, demonstrated the role of eosinophils in the hosts response to tick feeding. Serological examination revealed elevated anti-A hebraeum lgG titres following inoculation. These titres were found to decrease in the ten weeks after inoculation, despite the hosts being repeatedly infested with A hebraeum. Although the IgG titres of naive control hosts increased after each tick infestation, they failed to reach the titres achieved through inoculation. Western blot analysis of serum from inoculated hosts recognized most of the A. hebraeum proteins against which it was screened.
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  • Date Issued: 1993

An investigation of the intention to leave or stay of health care professionals at St. Andrews Hospital

  • Authors: Amanambu, Rochelle Aneeta
  • Date: 2014
  • Subjects: Medical personnel -- Job satisfaction -- South Africa -- Eastern Cape -- Case studies Medical personnel -- Job stress -- South Africa -- Eastern Cape -- Case studies Hospitals -- South Africa -- Eastern Cape -- Administration Hospitals -- Medical staff -- South Africa -- Eastern Cape Hospitals -- Officials and employees -- South Africa -- Eastern Cape -- Turnover Health services administration -- South Africa -- Eastern Cape Health planning -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , MBA
  • Identifier: vital:823 , http://hdl.handle.net/10962/d1011091
  • Description: Background: The demand for and retention of talent worldwide is aggravated by revolutionary trends that include global competition, demographic changes and technological advances. In South Africa this phenomenon according to Frost (2002) is further challenged by the emigration of skilled people; the relative scarcity of specialist and managerial employees; employment equity and affirmative action procedures. But the development of strategies first requires an understanding of the factors which influence decisions to leave or stay particularly in rural and remote areas. St. Andrews Hospital is a rural district hospital in Ugu District, KZN. Its remoteness from urban areas and the lack of resources contributes towards challenges of attracting and retaining health care professionals to the area. It is the aim of this study to identify the ten most prevalent turnover and retention factors in a rural district hospital with the intention of making recommendations towards strategies to mitigate turnover and improve retention of health care professionals. This study will not only serve the local Human Resource Department but may also be used to inform district and provincial policies as well as departments’ decisions in the design or the review of current retention strategies aimed at reducing turnover. Method: The survey method was used to collect the primary data by distribution of self-administered questionnaires to Health Care Professionals at St. Andrews Hospital. Of the one hundred and fifty questionnaires distributed, one hundred and seven were returned (71% response rate) and formed the basis of the study. Results: Based on the impact scores, the top three turnover factors identified were, the way the organisation is led by top management (0.934); the size of the workload (0.862); and the way problems are dealt with by managers in the organisation (0.817). No statistically significant relationships were found between turnover factors and biographical variable. Availability of quality health services was ranked as the external factor that had the highest influence (78%) on turnover, while geographical location was ranked the lowest. The main reason given by respondents for leaving their previous employment was promotion, followed by distance and personal/family reasons. The top three retention factors identified from the impact scores were the quality of relationships with colleagues (1.698); the amount of support received from managers and colleagues (1.484); and the level of engagement and involvement with the job (1.390). This demonstrates that the salary package often thought to be a first priority factor Mobley, Horner and Hollingsworth (1978); Mobley (1982) and Herzberg (2003) is far less of a determining factor at St. Andrews Hospital than management support, job involvement and person-organisation fit as well as the social relationships formed in the workplace. A positive relationship was found between leadership and job dimension factors at the 1% level of significance. This supports the strong social bond (person-organisation fit) formed in the work environment between management and colleagues that supports retention and increases level of commitment. An important result of the study was that 46% of the respondents were thinking of leaving the town within the year while 29% were considering resigning from St. Andrews Hospital within the year. Conclusion: The results reveal a complex interaction of factors impacting on turnover and retention. The Human Resource Management function has a pivotal role to play in improving its ability to attract and retain professionals through developing comprehensive strategies based on external and internal and environmental factors. The study conveys to the St. Andrews Hospital management that turnover and retention factors are unique to the location and the working environment and differs amongst Health Care Professionals – this should be deliberated on when formulating Hospital Human Resource retention policies.
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  • Date Issued: 2014

A review of the geology of primary tin deposits with emphasis on the factors that control grade and tonnage

  • Authors: Archer, Paul D
  • Date: 1981
  • Subjects: Tin ores , Granite , Geology , Tonnage
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4912 , http://hdl.handle.net/10962/d1001572
  • Description: "The purpose of this dissertation is ... to review the economic geology of primary tin deposits and the geological factors that control grade and tonnage . The work concludes with a discussian of the implications of these geological controls on evaluation"-- Introd., p. 1
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  • Date Issued: 1981

Hippocampus: seahorse; brain-structure; spatial map; concept

  • Authors: Armstrong, Beth Diane
  • Date: 2010
  • Subjects: Hippocampus (Brain) Sea horses -- Symbolic representation Meaning (Philosophy) Deleuze, Gilles, 1925-1995 Escher, M C (Maurits Cornelis), 1898-1972 Visual perception Space perception Optical art Art -- Themes, motives
  • Language: English
  • Type: Thesis , Masters , MFA
  • Identifier: vital:2427 , http://hdl.handle.net/10962/d1002224
  • Description: Through an exploration of both sculptural and thought processes undertaken in making my Masters exhibition, ‘Hippocampus’, I unpack some possibilities, instabilities, and limitations inherent in representation and visual perception. This thesis explores the Hippocampus as image (seahorse) and concept (brain-structure involved in cognitive mapping of space). Looking at Gilles Deleuze’s writings on representation, I will expand on the notion of the map as being that which does not define and fix a structure or meaning, but rather is open, extendable and experimental. I explore the becoming, rather than the being, of image and concept. The emphasis here is on process, non-representation, and fluidity of meaning. This is supportive of my personal affirmation of the practice and process of art-making as research. I will refer to the graphic prints of Maurits Cornelis Escher as a means to elucidate a visual contextualization of my practical work, particularly with regard to the play with two- and three-dimensional space perception. Through precisely calculated ‘experiments’ that show up the partiality of our visual perception of space, Escher alludes to things that either cannot actually exist as spatial objects or do exist, but resist representation. Similarly I will explore how my own sculptures, although existing in space resist a fixed representation and suggest ideas of other spaces, non-spaces; an in-between space that does not pin itself down and become fixed to any particular image, idea, objector representation.
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  • Date Issued: 2010

Social Media usage in low-income communities: Opportunities and constraints in Buffalo City Metropolitan Municipality, Eastern Cape

  • Authors: Botchway, Stanley Aubyn
  • Date: 2019
  • Subjects: Social media
  • Language: English
  • Type: Thesis , Masters , MSoc. Sci
  • Identifier: http://hdl.handle.net/10353/17717 , vital:41150
  • Description: Social media is 21st century phenomenon has captured the attention of millions of people across the globe and has hitherto, permeated through all facet of our contemporary life. It has become the important conduit through which people far and near interact. Sharing of information, communicating, collaborating, engaging are some of the visible highlights of Social Media. Social media usage cut across different demographics. This is due to the unique characteristics of social media which includes openness, participation and sharing. The purpose of this study is to investigate the impact such usage have on less advantaged communities and how it can be used to further their cause in achieving socioeconomic parity. This study is qualitative in nature and it relied on semi-structured interviews and observations to collect data. Purposive and convenience sampling was used to select respondents. The findings of the study indicate that utilizing social media for the utmost gain is imperative in that the presence of new technologies has revolutionised the way people socialise beyond real time and boundaries. It was also noted that social media is the new norm as such societies far and beyond need to harness the potential not only for the social media generation but for the communities within its reach. Thus, researching into the impact this phenomenon has on the poorest communities is of great importance for both the public and policy makers. This study however recommends regulation of social media in order to contain security risks that it poses. It is therefore important to enhance internet security to protect the privacy threats. It is also important to invest more on issues of information and communication technology on low-income communities
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  • Date Issued: 2019

Assessing the vulnerability of resource-poor households to disasters associated with climate variability using remote sensing and GIS techniques in the Nkonkobe Local Municipality, Eastern Cape Province, South Africa

  • Authors: Chari, Martin Munashe
  • Date: 2016
  • Subjects: Climatic changes -- Forecasting Natural resources -- Remote sensing Droughts -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10353/2425 , vital:27837
  • Description: The main objective of the study was to assess the extent to which resource-poor households in selected villages of Nkonkobe Local Municipality in the Eastern Cape Province of South Africa are vulnerable to drought by using an improvised remote sensing and Geographic Information System (GIS)-based mapping approach. The research methodology was comprised of 1) assessment of vulnerability levels and 2) the calculation of established drought assessment indices comprising the Normalized Difference Vegetation Index (NDVI) and the Normalized Difference Water Index (NDWI) from wet-season Landsat images covering a period of 29 years from 1985 to 2014 in order to objectively determine the temporal recurrence of drought in Nkonkobe Local Municipality. Vulnerability of households to drought was determined by using a multi-step GIS-based mapping approach in which 3 components comprising exposure, sensitivity and adaptive capacity were simultaneously analysed and averaged to determine the magnitude of vulnerability. Thereafter, the Analytical Hierarchy Process (AHP) was used to establish weighted contributions of these components to vulnerability. The weights applied to the AHP were obtained from the 2012 - 2017 Nkonkobe Integrated Development Plan (IDP) and perceptions that were solicited from key informants who were judged to be knowledgeable about the subject. A Kruskal-Wallis H test on demographic data for water access revealed that the demographic results are independent of choice of data acquired from different data providers (χ2(2) = 1.26, p = 0.533, with a mean ranked population scores of 7.4 for ECSECC, 6.8 for Quantec and 9.8 for StatsSA). Simple linear regression analysis revealed strong positive correlations between NDWI and NDVI ((r = 0.99609375, R2 = 1, for 1985), 1995 (r = 0.99609375, R2 = 1 for 1995), (r = 0.99609375, R2 = 1 for 2005) and (r = 0.99609375, R2 = 1 for 2014). The regression analysis proved that vegetation condition depends on surface water arising from rainfall. The results indicate that the whole of Nkonkobe Local Municipality is susceptible to drought with villages in south eastern part being most vulnerable to droughts due to high sensitivity and low adaptive capacity.
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  • Date Issued: 2016

The development of an improved coded-pulse, vertical-incidence ionosonde

  • Authors: Cretchley, Brian Brind
  • Date: 1979
  • Subjects: Ionosondes Ionospheric sounds Computer simulation
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5436 , http://hdl.handle.net/10962/d1001989
  • Description: This thesis describes the theoretical development of a new ionospheric sounding system. The different types of ionosonde, their prime objectives, and their relative merits and demerits are discussed. The various types of code and their correlation functions are described. The essential requirements of the new system are listed, and suitable codes are found for it. Computer calculations and mathematical derivations demonstrate the (theoretical) suitability of these codes under all conditions. Essentials of the mode of operation of the system and details of its design are specified, and computer simulations are used to examine relevant aspects of its operation. Finally, since the construction of the system is not complete and results cannot therefore be presented, the present state of construction of the system is described
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  • Date Issued: 1979

Audience observations of art, identity and schizophrenia : possibilities for identity movement

  • Authors: Farquharson, Kirsten Leigh
  • Date: 2014
  • Subjects: Mental illness -- Social aspects , Stigma (Social psychology) , Identity (Psychology) , Schizophrenia -- Treatment , Art therapy -- Research , Art, South African -- 21st century -- Exhibitions
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:3223 , http://hdl.handle.net/10962/d1012992
  • Description: This research situates itself in the study of stigma in mental illness. In particular, the aim is to explore the potential that art making and exhibiting has in reducing stigma for those with a diagnosis of schizophrenia. The research explores one aspect (the exhibition stage) of an "art as therapy" project. The exhibiting of one’s artwork aims to counter limiting "patient" identities by allowing those labelled as psychiatric patients to extend their self-identity to an alternative identity of the "artist". However, this idea only stands strong if the artwork created is not discriminated against as "naïve art" and is accepted or at least considered for acceptance as legitimate nonprofessional artwork. This research explores the ways in which art created by inpatients with a diagnosis of schizophrenia is received by the general art-viewing public at the National Arts Festival in Grahamstown, South Africa. The study uses a discourse analytic framework to analyse the interviews of members of the public who attended the art exhibition of patient artwork. It will examine the ways in which the public construct the artworks and how they position the makers of this art across a continuum, from patient to artist. The results of this thesis have implications for rehabilitation practices for people with a diagnosis of schizophrenia particularly with regard to opportunities to "perform" alternative identities in public spaces.
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  • Date Issued: 2014

Research portfolio

Karen Horney : a psychobiographical study

  • Authors: Green, Sarah-Jane
  • Date: 2007
  • Subjects: Horney, Karen, 1885-1952 Women psychologists Levinson, Daniel J., d.1994 Levinson, Daniel J., d.1994 -- The seasons of a woman's life
  • Language: English
  • Type: Thesis , Masters , MSocSc
  • Identifier: vital:3186 , http://hdl.handle.net/10962/d1008374
  • Description: This psychobiography on the life of Karen Horney is an exploratory-descriptive study that aims to explore and describe Horney's life structure development according to Daniel Levinson's (1996) theory of adult development. The method of research uses a qualitative single-case research design that studies her life over her entire lifespan and highlights the individual characteristics of Horney in a holistic manner within her socio-historical context. A purposive sampling procedure was used to select Karen Horney as the subject of the research and only published data was analyzed in the research. Multiple sources of data are used to obtain the information in this research, including an autobiography and three biographies written by three different authors. This data is organized according to the temporal sequence of her lifespan and the developmental periods and time frame of Levinson's theory. Horney's life is described and explored to highlight those areas of her life that conform to the developmental theory and those aspects of her life that are not included in the theoretical constructs of Levinson 's theory. By exploring the significant relationships that Horney developed throughout her life with family, friends, work colleagues, community and religious affiliations, and the important issues in her development, this study verifies Levinson's theory by corroborating his conceptualisation of adult development as a process of sequential stages divided into four main eras of development, linked by three periods of transition. A shortcoming of Levinson's theory relates to his omission of self-esteem issues and religious concerns as relevant factors experienced during the era of pre-adulthood and spiritual concerns during the era of late adulthood.
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  • Date Issued: 2007

Contributions to the theory of group rings

  • Authors: Groenewald, Nicolas Johannes
  • Date: 1979
  • Subjects: Group rings Group theory -- Mathematics
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:5391 , http://hdl.handle.net/10962/d1001980
  • Description: Chapter 1 is a short review of the main results in some areas of the theory of group rings. In the first half of Chapter 2 we determine the ideal theoretic structure of the group ring RG where G is the direct product of a finite Abelian group and an ordered group with R a completely primary ring. Our choice of rings and groups entails that the study centres mainly on zero divisor ideals of group rings and hence it contributes in a small way to the zero divisor problem. We show that if R is a completely primary ring, then there exists a one-one correspondence of the prime zero divisor ideals in RG and RG¯, G finite cyclic of order n. If R is a ring with the property α, β € R, then αβ = 0 implies βα = 0, and S is an ordered semigroup, we show that if ∑α¡s¡ ∈ RS is a divisor of zero, then the coefficients α¡ belong to a zero divisor ideal in R. The converse is proved in the case where R is a commutative Noetherian ring. These results are applied to give an account of the zero divisors in the group ring over the direct product of a finite Abelian group and an ordered group with coefficients in a completely primary ring. In the second half of Chapter 2 we determine the units of the group ring RG where R is not necessarily commutative and G is an ordered group. If R is a ring such that if α, β € R and αβ = 0, then βα = 0, and if G is an ordered group, then we show that ∑αg(subscript)g is a unit in RG if and only if there exists ∑βh(subscript)h in RG such that∑αg(subscript)βg(subscript)-1 = 1 and αg(subscriptβh is nilpotent whenever GH≠1. We also show that if R is a ring with no nilpotent elements ≠0 and no idempotents ≠0,1, then RG has only trivial units. In this chapter we also consider strongly prime rings. We prove that RG is strongly prime if R is strongly prime and G is an unique product (u.p.) group. If H ⊲ G such that G/H is right ordered, then it is shown that RG is strongly prime if RH is strongly prime. In Chapter 3 results are derived to indicate the relations between certain classes of ideals in R and RG. If δ is a property of ideals defined for ideals in R and RG, then the "going up" condition holds for δ-ideals if Q being a δ-ideal in R implies that QG is a δ-ideal in RG. The "going down" condition is satisfied if P being a δ-ideal in RG implies that P∩ R is a δ-ideal in R. We proved that the "going up" and "going down" conditions are satisfied for prime ideals, ℓ-prime ideals, q-semiprime ideals and strongly prime ideals. These results are then applied to obtain certain relations between different radicals of the ring R and the group ring (semigroup ring) RG (RS). Similarly, results about the relation between the ideals and the radicals of the group rings RH and RG, where H is a central subgroup of G, are obtained. For the upper nil radical we prove that ⋃(RG) (RH) ⊆ RG, H a central subgroup of G, if G/H is an ordered group . If S is an ordered semigroup, however, then ⋃(RS) ⊆ ⋃(R)S for any ring R. In Chapter 4 we determine relations between various radicals in certain classes of group rings. In Section 4.3, as an extension of a result of Tan, we prove that P(R)G = P(RG) , R a ring with identity , if and only if the order of no finite normal subgroup of G is a zero divisor in R/P(R). If R is any ring with identity and H a normal subgroup of G such that G/H is an ordered group, we show that ⊓(RH)·RG = ⋃(RG) = ⊓(RG) , if ⋃(RH) is nilpotent. Similar results are obtained for the semigroup ring RS, S ordered. It is also shown if R is commutative and G finite of order n, then J(R)G = J(RG) if and only if n is not a zero divisor in R/J(R), J(R) being the Jacobson radical of R. For the Brown HcCoy radical we determine the following: If R is Brown McCoy semisimple or if R is a simple ring with identity, then B(RG) = (0), where G is a finitely generated torsion free Abelian group. In the last section we determine further relations between some of the previously defined radicals, in particular between P(R), U(R) and J(R). Among other results, the following relations between the abovementioned radicals are obtained: U(RS) = U(R)S = P(RS) = J(RS) where R is a left Goldie ring and S an ordered semigroup with unity
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  • Date Issued: 1979

The strategic impact of HIV/AIDS on first level component suppliers to the motor industry, located in the Nelson Mandela Metropole

  • Authors: Hughes, Edward Peter Clive
  • Date: 2001
  • Subjects: Automobile industry and trade -- Management , Labor productivity , Production management , AIDS (Disease) -- Economic aspects -- South Africa
  • Language: English
  • Type: Thesis , Masters , MTech
  • Identifier: vital:10943 , http://hdl.handle.net/10948/d1006722 , Automobile industry and trade -- Management , Labor productivity , Production management , AIDS (Disease) -- Economic aspects -- South Africa
  • Description: HIV/AIDS is undoubtedly the single most important and daunting health problem facing Africa. Globally too, this is one of the most serious health, medical and social preoccupations of our time (Chinery-Hesse, 2000: 1). The aim of this research study is to evaluate the strategic impact of HIV/AIDS on first level component suppliers to the motor industry located in the Nelson Mandela Metropole. To achieve this aim a literature study was undertaken to determine the patterns of development, the infection statistics and to explore strategic options and actions for dealing with the effects of the disease. An empirical study has been conducted to assess the opinions of senior management within first level component suppliers. The results from the study indicate that most companies in the selected group believe that HIV/AIDS will have a serious impact on their organisations. In conclusion, various recommendations have been made with regards to the findings ascertained in the literature review and empirical study.
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  • Date Issued: 2001

Leaders' and participants' perceptions of the management of the Life Science Project in Namibia

  • Authors: Kirkegaard, Niels Hugo
  • Date: 2002
  • Subjects: Life Science Project (Namibia) Educational leadership Educational leadership -- Namibia School management and organization School management and organization -- Namibia
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1662 , http://hdl.handle.net/10962/d1003545
  • Description: After Independence in 1991, Namibia embarked on implementing a new and different educational system. This system was seen as a radical departure from the old apartheid system. The Namibian government approached Ibis, a Danish NGO, to support the change process by establishing and developing a new subject, life science, in Junior Secondary schools in Namibia through the Life Science Project (LSP). In a project of this nature, where a foreign (Danish) educational intervention in a relatively young and new democracy is the issue, cross-cultural aspects are likely to emerge, and these are the focus of this study. This half-thesis is an attempt to illuminate, not to evaluate, managerial as well as cross-cultural features of the project based on perceptions of selected Danish managers and Namibian advisory teachers from the former LSP expressed in the goal of the research: - To explore selected leaders’ and participants’ perception of the management of the Life Science Project. In line with this goal, I elected to conduct the research in the interpretive paradigm, using unstructured interviews as my chief source of data. The findings illuminate what would appear to be an inconsistency in the management of the project. The project seemed to be able to accommodate regional and even personal differences and to be flexible to internal changes. At the same time it appears that in its relationship to the external or task environment it did not show the same openness and flexibility to accommodate diversity. It is suggested that this could be a result of the apparent failure on the part of the project to clarify its own underlying values. The study also reveals interesting and unexpected perceptions of leadership, which may also be interpreted in terms of cultural values and beliefs. These two features of managerial issues could lead one to reflect upon the importance of recognising values in organisations which work across cultures.
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  • Date Issued: 2002

An investigation into fan identity among supporters of the English soccer premier league in Lusaka, Zambia

  • Authors: Komakoma, Leah
  • Date: 2006
  • Subjects: Soccer -- Zambia -- Lusaka Soccer fans -- Zambia -- Lusaka Soccer -- Social aspects -- Zambia -- Lusaka Mass media and sports -- Zambia -- Lusaka , Sports journalism -- Zambia -- Lusaka , Sports -- Sociological aspects -- Zambia -- Lusaka
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:3448 , http://hdl.handle.net/10962/d1002902
  • Description: This study investigates Zambians’ construction of identities based on their following of the English soccer premier league. The study seeks to understand how Zambian supporters of this league construct their identities based on their encounter with foreign teams/players and how they appropriate the meanings obtained through such viewing in their daily lives. The study is informed by the theories of fandom. Using an ethnographic critique of the media imperialism thesis, the study attempts to explore the meanings that the fans of the English soccer league in urban Lusaka make of the mediated soccer games, while in and outside the viewing spaces – the bars – where the games are ritually watched in groups. Based on the qualitative methods of focus group discussions, individual in-depth interviews and observations, the study probes the phenomenon of the consumption of English premier league football in countries abroad, focusing specifically on the experiences of fans in Lusaka, Zambia. Observation of this phenomenon in Lusaka reveals that fans find pleasure in the tactics that the teams in the league display, the professionalism of the players, goal scoring and self-empowerment for the few women supporters. This study probes these issues in greater depth. The foremost conclusion of the research is that it neither completely rejects nor accepts the media imperialism thesis. Instead, meanings should be understood within the context of the lived experience and reality of the fans.
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  • Date Issued: 2006

Electrochemical studies of gold bioaccumulation by yeast cell wall components

  • Authors: Lack, Barbara Anne
  • Date: 1999
  • Subjects: Hydrometallurgy , Electrochemical analysis , Gold ores , Gold
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4311 , http://hdl.handle.net/10962/d1004969 , Hydrometallurgy , Electrochemical analysis , Gold ores , Gold
  • Description: Gold, amongst other group 11 metals, was almost certainly one of the first three metals known to man. In addition to the economic importance of the metal, gold has a wide variety of applications in the medical, electrocatalytical and micro-electronics fields. However, the determination of gold ions in solution, with accuracy, precision, sensitivity and selectivity is still an interesting and much debated topic in analytical chemistry. A system whereby gold ions have been successfully detected employing an electrochemical technique, known as stripping voltammetry, has been developed. The electrochemical method was chosen over other available techniques for the sensitivity, particularly at low concentrations, and selectivity properties; notably in the presence of other metal ions. Under acidic conditions, the electrochemical technique was applied and the presence of gold(III), at a concentration of 2.53 x 10⁻⁵ mol dm⁻³ in a mine waste water sample, was detected. Biomass, in particular yeast and algal types, have been successfully employed in extracting low concentrations of gold ions from industrial effluents. The manipulation of the biological facility for mineral interaction, biohydrometallurgy, may yield numerous potential new technologies. South Africa in particular would benefit from this area of research, since the country is a major ore and metal refining country and if the output and the efficiency of the mines could be improved, even by a small percentage, the financial rewards would be vast. In this study, the application of adsorptive cathodic stripping voltammetry (AdCSV) of gold(III) in the presence of various Saccharomyces cerevisiae cell wall components, was investigated to determine which, if any, were involved specifically in the chemical binding of the gold ions. The chitin and mannan extracts showed the most promise with detection limits of 1.10 x 10⁻⁶ mol dm⁻³ and 9 x 10⁻⁹ mol dm⁻³, respectively; employing the AdCSV technique. A modification of the stripping voltammetry technique, Osteryoung square wave stripping voltammetry (OSWSV), provided the lowest detection limit, for gold(IIl) in the presence of mannan, of 1.70 x 10⁻¹¹ mol dm⁻³ ; utilising a modified carbon paste electrode. The detection of gold(III) has been shown to be dependent on the type of electrode employed, the electrolyte solution and the presence of interfering agents. The effect of copper(II) and silver(I) on the detection of the gold(III) in solution was investigated; whilst the silver(I) has shown no detrimental effects on gold (III) detection systems, copper(II) has indicated the possibility of forming an inter-metallic compound with the gold(III). However, mannan has shown to selectively and preferentially bind the gold(III) in the presence of a ten-fold excess of copper(II). Nuclear magnetic resonance (NMR) and infrared (IR) spectroscopy, as well as computer modelling techniques were employed to further investIgate the mannan-gold(III) interaction and proposed complex formed. The NMR, IR and computer modelling data are in agreement with the electrochemical data on proposing a mannan-gold(III) complex. The co-ordination site was established to be in the vicinity of the H-I and H-2 protons and the gold(III) adopts a square-planar geometry upon co-ordination. The benefits of the research are useful from a biological perspective (i. e. as more is known about the binding sites, microbiologists/biochemists may work on the optimisation of parameters for these sites or work could be furthered into the enhanced expression of the sites) and an industrial one. In addition to the' two major benefits, an improved understanding of gold and its chemistry would be achieved, which is advantageous for other fields of research as well.
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  • Date Issued: 1999

Sensory dominance : an experiment across cultures

  • Authors: Locke, Hester W
  • Date: 1977
  • Subjects: Perception -- Testing , Senses and sensation -- Testing , Dominance (Psychology)
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:3214 , http://hdl.handle.net/10962/d1012744
  • Description: Physical and intellectual differences in the home environment of Xhosa and White children suggested that the interaction of touch and vision in situations of sensory conflict and the development of dominance may be different in children from these homes. Children aged 5-13 years were tested on apparatus which created a conflict of tactual and visual judgement about the perceived size of the stimulus. Xhosa and White subjects performed similarly except when only tactual judgement was allowed and the Xhosa group were less influenced by touch. The study concludes that for children touch and vision contribute equally to the resolution of sensory conflict when both senses are active in size-judgements and when only one mode is allowed for judging then the resolution is biased towards this mode. This outcome is different from that of experiments with adults and has implications for theories derived from them.
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  • Date Issued: 1977

Evaluating support service co-operation in the Netcare-Settlers public private partnership, Grahamstown, South Africa

  • Authors: Mahote, Tulisa
  • Date: 2015
  • Subjects: Settlers Hospital , Netcare 911 , Public-private sector cooperation -- South Africa -- Grahamstown , Privatization -- South Africa , Medical care -- Privatization -- South Africa , Health services accessibility -- South Africa , Contracting out -- South Africa
  • Language: English
  • Type: Thesis , Masters , MSocSc
  • Identifier: vital:3408 , http://hdl.handle.net/10962/d1020834
  • Description: The neo-liberal restructuring of state assets and facilities, which has taken place internationally over the past three decades, as well as in South Africa, has been a matter of great controversy. Privatisation, in particular, has been a polarising issue, especially when applied to fields like healthcare. Supporters of privatisation view it as cutting costs, mobilising funding, expertise and innovation, resulting in improved delivery, and opening possibilities for a spread of ownership. Critics claim the process involves retrenchments, declining services for the (poorer) majority of people, and a focus on the elites as citizens become transformed into customers, and with any economic empowerment going to the already prosperous. This thesis examines these issues by looking at the privatisation of hospitals in South Africa, with a case study of the Netcare-Settlers Public Private Partnership (PPP) (also known as the Settlers Private Hospital) in Grahamstown, South Africa. Netcare is South Africa’s largest private hospital company, and also has substantial operations in the United Kingdom. The thesis sets out the context: a highly inequitable healthcare system in the country, the rise of privatisation in the apartheid and post-apartheid eras, and healthcare privatisation. In terms of the Netcare-Settlers PPP, the thesis examines how the PPP was structured and developed, focusing on the impact of the PPP on non-clinical operations. The thesis argues that the results of the PPP are mixed, that it has greatly improved areas like facilities, maintenance, cleaning and catering, performed less well in increasing the doctor/ patient ratio or in attracting specialists, and is associated with the widespread and problematic use of outsourcing of service workers like cleaners and security. Overall, the PPP has improved healthcare, with some effective sharing of resources between the public and private parts of the hospital, but also relies on a pool of relatively low waged, under-unionised, labour. In terms of the general debate over privatisation, the Netcare-Settlers PPP shows that both supporters and critics have some valid points, and that privatisation in practice is not an either/ or, black/ white, good/ bad proposition, but something more complex. The success and failure of PPPs depend on the details of the contracts, and these can be used to maximise the performance of both the public and private partners. Better contracts may help avoid the uneven results seen at institutions like the Netcare-Settlers PPP.
  • Full Text:
  • Date Issued: 2015

An investigation into the use of traditional Xhosa dance to teach mathematics: a case study in a Grade 7 class

  • Authors: Mbusi, Nokwanda Princess
  • Date: 2012
  • Subjects: Mathematics -- Study and teaching (Primary) Teaching -- Aids and devices -- Research Xhosa (African people) -- Music Education, Primary -- South Africa -- Eastern Cape , Music in mathematics education
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1617 , http://hdl.handle.net/10962/d1003499
  • Description: This study seeks to explore mathematical concepts embedded in traditional Xhosa dance and how these concepts can be incorporated into a learning programme for the teaching and learning of mathematics. The study seeks to gain insight into whether learners could benefit from the implementation of such a learning programme. Learners from a Grade 7 class in a rural school performed traditional Xhosa dances and their performances were captured through video recording. The video recordings were then observed and analysed to determine the mathematical concepts embedded in the dances. These concepts were then linked to those found in the Grade 7 mathematics curriculum. A learning programme integrating mathematical concepts from the dance activities with mathematical concepts from the Grade 7 curriculum was then designed. The learning programme contained mathematical problem solving activities that required learners to re-enact the dance performances in order to find the required solutions. The learning programme was then implemented with the learners over a period of three weeks. During the implementation, learners’ behaviour towards the learning experience was observed, their engagement with the problem solving activities as well as their strategies for solving the problems, were carefully observed. Also, their interactions with each other were noted. After the implementation of the learning programme, focus group interviews were held with learners to determine their opinions, attitudes and feelings about their experience of learning mathematics through traditional Xhosa dance. Key findings indicated that traditional Xhosa dance can be used as a medium for learning many concepts in the mathematics curriculum; the use of the dance gave learners an opportunity to learn mathematics from a familiar context and to participate actively and collaboratively in their learning. Also, it emerged that the use of dance to teach mathematics had potential to help improve learners’ attitudes towards mathematics. Conclusions were reached that the dance had potential for use as a means for the meaningful learning of mathematics. However, limitations and challenges with the study were identified, such as its limited replicability in other mathematics classrooms.
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  • Date Issued: 2012

A phenomenological study of leadership in the Rhodes Unversity Mathematics Education Project (RUMEP)

  • Authors: Michael, Vanessa Jane
  • Date: 2001
  • Subjects: Rhodes University -- Mathematics education project Educational leadership
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1701 , http://hdl.handle.net/10962/d1003584
  • Description: Few terms in organisational studies inspire less agreement than leadership. It is a slippery concept and much that is written on the subject is confusing and contradictory. Early theories of leadership have, generally, reduced leadership behaviour to a concern for task balanced against a concern for the well-being of employees. This two-dimensional approach has proved to be a limited conceptualisation of leadership. In response, over the past thirty years, researchers have tried to highlight the less rationalistic, more intangible, aspects of leadership. However, there is still very little in leadership research that conveys a sense of the leader as a person. I have argued, in this study, that the reason for this lies in the fact that most leadership research has been conducted along positivistic lines and, therefore, cannot take into account the values, feelings, morals and life experiences of the human beings being studied. Thus, for the human being to take centre-stage in leadership enquiry, a different research paradigm needs to be explored. I have chosen to use phenomenological enquiry as an avenue for examining how John Stoker, the leader of the Rhodes University Mathematics Education Project (RUMEP), experiences being a leader. This is because phenomenology, in both theory and practice, privileges the nature of the meanings that people construct in their lives and that guide their actions. In adopting such a methodology my research findings have examined a number of issues that are of interest to current leadership researchers, however they have also highlighted a number of concerns that have not been explored thoroughly in the leadership literature. These include the importance of the individual leader’s action, intention and will in shaping an organisation, the complex nature of a leader’s creativity within the organisation and possible differences between educational leaders and business leaders. In adopting a phenomenological perspective the eccentricity and fulness of an individual leader’s action is expressed through the research, however, the research also focusses on how the researcher translates and evolving philosophical understanding into sound methodology. Therefore, interwoven into the discussions on leadership there are reflections on how I applied phenomenological theory. The purpose of these reflections is to deliberate on the appropriateness of applying such a methodology to the eclectic field of leadership and to show how my own developing philosophical attitude has transformed into practice.
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  • Date Issued: 2001

An analysis of how geogebra can be used as a visualisation tool by selected teachers to develop conceptual understanding of the properties of geometric shapes in grade 9 learners: a case study in Namibia

  • Authors: Mwiikeni, Eramus
  • Date: 2017
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: http://hdl.handle.net/10962/6989 , vital:21207
  • Description: According to Rosken & Rolka (2006), learning mathematics through visualisations can be a powerful tool to explore mathematical problems and give meaning to mathematical concepts and relationships between them. “Visualisation can reduce the complexity of mathematical problems when dealing with a multitude of information” (p.458). This case study focused on using GeoGebra as a visualisation tool to teach angle properties in Grade 9 geometry. This study set out to analyse how GeoGebra visualisations can be used by selected teachers to teach for conceptual understanding. The research is based on a constructivist view of learning and is oriented within an interpretive paradigm. The methodology used is a qualitative case study. The study was conducted in one school and involved 3 mathematics teachers who were purposefully selected because they showed willingness to use technology in their teaching. I used classroom observations and interviews to collect the data. The study identified a number of factors from the participants that related to using GeoGebra in teaching for conceptual understanding. These include the effective use of dynamic visuals to build on prior knowledge, using multiple representations through image generation and image transformation to make connections and using visuals to justify mathematics ideas. The results from this study indicated that GeoGebra can indeed be used effectively as a teaching tool to teach for conceptual understanding in mathematics.
  • Full Text:
  • Date Issued: 2017
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