List of Titles

Adoption and sustained use of M-Commerce to improve efficacy of construction SMMEs

Authors: Williams, Zenande
Date: 2011
Subjects: Construction industry , Mobile commerce , Small business , Computer-assisted instruction , Interactive videos
Language: English
Type: Thesis , Masters , MCom (Information Systems)
Identifier: vital:11125 , http://hdl.handle.net/10353/528 , Construction industry , Mobile commerce , Small business , Computer-assisted instruction , Interactive videos
Description: E-commerce has been said to bring value to businesses by improving business efficiency and effectiveness and thus providing business with a competitive advantage through the potential benefits that it offers (Cloete, Courtney & Fintz, 2002). However, despite the potential benefits that e-commerce can offer, the adoption of B2C e-commerce in South African construction SMMEs is low and this is due to the challenges associated with e-commerce (Vaithanathan, 2010; Uzoka, Shemi & Seleka, 2007; Love & Irani, 2004; Anumba & Ruikar, 2002). These e-commerce challenges include: high implementation costs, lack or poor infrastructure, inadequate resources, low use of e-commerce by suppliers and consumers, lack of access to e-commerce, computer illiteracy, deficiency in understanding the potential benefits of e-commerce and security concerns (Vaithanathan, 2010; Uzoka, Shemi, & Seleka, 2007; Mensah, Bahta, & Mhlanga, 2005; Cloete, Courtney, & Fintz, 2002). Therefore, due to these e-commerce challenges, construction SMMEs do not exploit the business advantages that e-commerce offers. In order to assist South African construction SMMEs in their efforts to improve their business effectiveness and efficiency through commercial technologies.
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Adoption, use and perception of Australian acacias around the world

- Kull, Christian A, Shackleton, Charlie M, Cunningham, Peter J, Ducatillon, Catherine, Dufour-Dror, Jean-Mark, Esler, Karen J, Friday, James B, Gouveia, António C, Griffin, A R, Marchante, Elizabete, Midgley, Steven J, Pauchard, Aníbal, Rangan, Haripriya, Richardson, David M, Rinaudo, Tony, Tassin, Jacques, Urgenson, Lauren S, van Maltitz, Graham P, Zenni, Rafael D, Zylstra, Matthew J

Authors: Kull, Christian A , Shackleton, Charlie M , Cunningham, Peter J , Ducatillon, Catherine , Dufour-Dror, Jean-Mark , Esler, Karen J , Friday, James B , Gouveia, António C , Griffin, A R , Marchante, Elizabete , Midgley, Steven J , Pauchard, Aníbal , Rangan, Haripriya , Richardson, David M , Rinaudo, Tony , Tassin, Jacques , Urgenson, Lauren S , van Maltitz, Graham P , Zenni, Rafael D , Zylstra, Matthew J
Date: 2011
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/182149 , vital:43804 , xlink:href="https://doi.org/10.1111/j.1472-4642.2011.00783.x"
Description: To examine the different uses and perceptions of introduced Australian acacias (wattles; Acacia subgenus Phyllodineae) by rural households and communities. Eighteen landscape-scale case studies around the world, in Vietnam, India, Réunion, Madagascar, South Africa, Congo, Niger, Ethiopia, Israel, France, Portugal, Brazil, Chile, Dominican Republic and Hawai‘i. Qualitative comparison of case studies, based on questionnaire sent to network of acacia researchers. Information based on individual knowledge of local experts, published and unpublished sources. We propose a conceptual model to explain current uses and perceptions of introduced acacias. It highlights historically and geographically contingent processes, including economic development, environmental discourses, political context, and local or regional needs. Four main groupings of case studies were united by similar patterns: (1) poor communities benefiting from targeted agroforestry projects; (2) places where residents, generally poor, take advantage of a valuable resource already present in their landscape via plantation and/or invasion; (3) regions of small and mid-scale tree farmers participating in the forestry industry; and (4) a number of high-income communities dealing with the legacies of former or niche use of introduced acacia in a context of increased concern over biodiversity and ecosystem services. Economic conditions play a key role shaping acacia use. Poorer communities rely strongly on acacias (often in, or escaped from, formal plantations) for household needs and, sometimes, for income. Middle-income regions more typically host private farm investments in acacia woodlots for commercialization. Efforts at control of invasive acacias must take care to not adversely impact poor dependent communities.
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Date Issued: 2011

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Advances in entomological methods for death time estimation

- Villet, Martin H, Amendt, Jens

Authors: Villet, Martin H , Amendt, Jens
Date: 2011
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/441722 , vital:73910 , https://doi.org/10.1007/978-1-61779-249-6_11
Description: The development of entomological methods for estimating the time of death has been rapid in the last decade, and new methods are on the horizon. These developments are reviewed with specific reference to experimental design, established and new techniques, and mathematical modelling for forensic retrodiction. The techniques include the use of electron microscopy, magnetic resonance imaging, computed tomography, cuticular hydrocarbon profiles, and real-time PCR to estimate the age of immature insects found on corpses, based on their stage of development. Near-infrared spectrograph and pteridine fluorescence techniques can be applied to this task on adult insects. The use of ecological succession in the carrion insect community is also introduced briefly. Finally, the creation and uses of standard techniques in forensic entomology is discussed. We recommend that two steps in this standardisation process are that physiological and ecological studies should be reported in physiological time wherever this is appropriate, and that the type of post-mortem interval being estimated should be stipulated more explicitly than is currently common.
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Date Issued: 2011

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Africa: unity, sovereignty and sorrow A book review

- Matthews, Sally

Authors: Matthews, Sally
Date: 2011
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/142387 , vital:38075 , DOI: 10.1080/02589001.2011.562007
Description: This ambitious book begins with the statement ‘By and large, the states of sub-Saharan Africa are failures’ (p. 1) and then sets out to explain state failure in Africa and to provide some ‘rational policy fantasies’ in response to this failure. The book builds on the work of scholars like Robert Jackson, William Reno and Jeffrey Herbst, with the particular focus of Englebert's book being on the domestic implications of the unconditional recognition of the sovereignty of African states. African states are internationally recognised despite lacking the features and not being able to perform the functions typically associated with statehood. Englebert's interest is to examine some of the domestic effects of this unconditional international recognition.
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Date Issued: 2011

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African carrion ecosystems and their insect communities in relation to forensic entomology

- Villet, Martin H

Authors: Villet, Martin H
Date: 2011
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/442439 , vital:73984 , http://www.globalsciencebooks.info/Online/GSBOnline/OnlinePT_5_1.html
Description: African carrion communities contain representatives of the same families that occur in carrion communities on other continents. Checklists and identification guides are tabulated, and the natural histories of core members of the terrestrial community are outlined. Because of strong phylogenetic trends in the biology of the families, the species are effectively ecological surrogates of their relatives elsewhere. These phylogenetic trends also allow the definition of a set of guilds of functionally equivalent species that unify the study of carrion communities world-wide, and a revised suite of guilds is described with both synecological and forensic purposes in mind. Although the decomposition process has been arbitrarily subdivided into stages, they have little direct relation to the dynamics of the carrion community, and should be treated as landmarks rather than phases. Community turnover follows a qualitatively predictable succession, with the greatest species richness and diversity around the ecotone-like transition from ‘wet-phase’ to ‘dry-phase’ carrion habitats. These habitats are differentiated along interacting ecological gradients of dietary quality, competition, and risk of predation, which are important to the core guilds. Competition and predation have strong effects on population dynamics of community members, but link particular species only weakly, so that the succession pattern largely reflects the autecology of the individual species. Discrete waves of species are absent, which increases the temporal resolution, and therefore the forensic value, of the succession as a ‘clock’. The forensic significance of various aspects of community and trophic dynamics are discussed, and means of applying ecological theory to investigations are reviewed.
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Date Issued: 2011

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African Languages And ICT Education

- Dalvit, Lorenzo, Murray, Sarah, Terzoli, Alfredo

Authors: Dalvit, Lorenzo , Murray, Sarah , Terzoli, Alfredo
Date: 2011
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/431166 , vital:72750 , https://www.scitepress.org/Papers/2011/33507/33507.pdf
Description: In South Africa, English plays a dominant role compared to African lan-guages in empowering domain. Better access to Education through the use of African languages is an object of heated debate. This paper shows that an intervention involving the use of an African language in the domain of ICT Education can change the attitudes of Black universi-ty students. The methodology used included a survey with preliminary and follow-up questionnaires and interviews and an intervention involv-ing the use of localised software and of an on-line glossary of computer terms translated, explained and exemplified in an African language (isiXhosa). This experience increased the support for the use of African languages as additional LoLT, even in the English-dominated field of study of Computer Science. This is an initial step towards promoting linguistic equality between English and African languages and social equality between their speakers.
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Date Issued: 2011

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African traditional medicine-antiretroviral interactions : effects of Sutherlandia frutescens on the pharmacokinetics of Atazanavir

- Müller, Adrienne Carmel

Authors: Müller, Adrienne Carmel
Date: 2011 , 2011-03-28
Subjects: Antiretroviral agents , Medicinal plants , Traditional medicine , AIDS (Disease) -- Treatment , HIV infections -- Drug therapy , Drug interactions , Pharmacokinetics
Language: English
Type: Thesis , Doctoral , PhD
Identifier: vital:3859 , http://hdl.handle.net/10962/d1013373
Description: In response to the urgent call for investigations into antiretroviral (ARV)-African traditional medicine (ATM) interactions, this research was undertaken to ascertain whether chronic administration of the ATM, Sutherlandia frutescens (SF) may alter the bioavailability of the protease inhibitor (PI), atazanavir (ATV), which may impact on the safety or efficacy of the ARV. Prior to investigating a potential interaction between ATV and SF in vitro and in vivo, a high performance liquid chromatography method with ultraviolet detection (HPLC-UV) was developed and validated for the bioanalysis of ATV in human plasma and liver microsomes. An improved and efficient analytical method with minimal use of solvents and short run time was achieved in comparison to methods published in the literature. In addition, the method was selective, linear, accurate and precise for quantitative analysis of ATV in these studies. Molecular docking studies were conducted to compare the binding modes and affinities of ATV and two major SF constituents, Sutherlandioside B and Sutherlandin C, with the efflux transporter, P-glycoprotein (P-gp) and the CYP450 isoenzyme, CYP3A4 to determine the potential for these phytochemicals to competitively inhibit the binding of ATV to these two proteins, which are mediators of absorption and metabolism. These studies revealed that modulation of P-gp transport of ATV by Sutherlandioside B and Sutherlandin C was not likely to occur via competitive inhibition. The results further indicated that weak competitive inhibition of CYP3A4 may possibly occur in the presence of either of these two SF constituents. The Caco-2 cell line was used as an in vitro model of human intestinal absorption. Accumulation studies in these cells were conducted to ascertain whether extracts and constituents of SF have the ability to alter the absorption of ATV. The results showed that the aqueous extract of SF significantly reduced ATV accumulation, suggesting decreased ATV absorption, whilst a triterpenoid glycoside fraction isolated from SF exhibited an opposing effect. Analogous responses were elicited by the aqueous extract and a triterpenoid glycoside fraction in similar accumulation studies in P-gp overexpressing Madin–Darby Canine Kidney Strain II cells (MDCKII-MDR1), which signified that the effects of this extract and component on ATV transport in the Caco-2 cells were P-gp-mediated. The quantitative analysis of ATV in human liver microsomes after co-incubation with extracts and components of SF was conducted to determine the effects of SF on the metabolism of ATV. The aqueous and methanolic extracts of SF inhibited ATV metabolism, whilst the triterpenoid glycoside fraction had a converse effect. Analogous effects by the extracts were demonstrated in experiments conducted in CYP3A4-transfected microsomes, suggesting that the inhibition of ATV metabolism in the liver microsomes by these SF extracts was CYP3A4-mediated. A combination of Sutherlandiosides C and D also inhibited CYP3A4-mediated ATV metabolism, which was in contrast to the response elicited by the triterpenoid fraction in the liver microsomes, where other unidentified compounds, shown to be present therein, may have contributed to the activation of ATV metabolism. The in vitro studies revealed the potential for SF to alter the bioavailability of ATV, therefore a clinical study in which the effect of a multiple dose regimen of SF on the pharmacokinetics (PK) of a single dose of ATV was conducted in healthy male volunteers. The statistical analysis showed that the 90 % confidence intervals around the geometric mean ratios (ATV + SF/ATV alone) for both Cmax and AUC0-24 hours, fell well below the lower limit of the "no-effect" boundary of 0.8 – 1.25, implying that the bioavailability of ATV was significantly reduced in this cohort of subjects. It may thus be concluded that if the reduction in bioavailability observed in this clinical study is found to be clinically relevant, co-administration of SF commercial dosage forms and ATV in HIV/AIDS patients may potentially result in subtherapeutic ATV levels, which may in turn contribute to ATV resistance and/or treatment failure. This research has therefore highlighted the potential risk for toxicity or lack of efficacy of ARV regimens which may result when ATMs and PIs are used concurrently and that patients and health care practitioners alike should be aware of these perils.
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Date Issued: 2011

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After Baines

- Walters, John Attwood Vereker

Authors: Walters, John Attwood Vereker
Date: 2011
Subjects: Baines, Thomas, 1820-1875 Baines, Thomas, 1820-1875 -- Biography Painting, South African -- Exhibitions Painters -- South Africa -- Biography
Language: English
Type: Thesis , Masters , MFA
Identifier: vital:2432 , http://hdl.handle.net/10962/d1004368
Description: By researching the life and work of Thomas Baines (1820 - 1875) in relation to a broader discourse of painting and the lived experience of being a 'white' male in a post-apartheid South Africa, I explore the ways in which this figure from the past has provoked the three series of artworks I have produced for my Master of Fine Art exhibition. This study has been divided into two parts, represented by the two chapters contained herein. Chapter One includes a critical retelling of Baines' biography and a discussion of the primary ways in which I have engaged with both the life and the working practice of this artist. I also address my own personal complicity in the constructions of 'the figure of Baines' as I have framed him both visually and textually during my work for this degree. Chapter Two describes some of the practicalities of my working process as a visual artist, including how I understand the theoretical and conceptual concerns which I raise in Chapter One to be visually manifest in my work. In this chapter, I also discuss my work in relation to the work of the contemporary South African artists William Kentridge and Johannes Phokela. The artistic practice of one artist imitating another artist's work is also explored as a central conceptual thread which could be seen to weave my verbal and visual production together.
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Date Issued: 2011

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Age validation, growth, mortality, and demographic modeling of spotted gully shark (Triakis megalopterus) from the southeast coast of South Africa

- Booth, Anthony J, Foulis, Alan J, Smale, Malcolm J

Authors: Booth, Anthony J , Foulis, Alan J , Smale, Malcolm J
Date: 2011
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/123630 , vital:35466 , https://spo.nmfs.noaa.gov/sites/default/files/pdf-content/2011/1091/booth.pdf
Description: This study documents validation of vertebral band-pair formation in spotted gully shark (Triakis megalopterus) with the use of f luorochrome injection and tagging of captive and wild sharks over a 21-year period. Growth and mortality rates of T. megalopterus were also estimated and a demographic analysis of the species was conducted. Of the 23 OTC (oxytetracycline) -marked vertebrae examined (12 from captive and 11 from wild sharks), seven vertebrae (three from captive and four from wild sharks) exhibited chelation of the OTC and f luoresced under ultraviolet light. It was concluded that a single opaque and translucent band pair was deposited annually up to at least 25 years of age, the maximum age recorded. Reader precision was assessed by using an index of average percent error calculated at 5%. No significant differences were found between male and female growth patterns (P>0.05), and von Bertalanffy growth model parameters for combined sexes were estimated to be L∞=1711.07 mm TL, k=0.11/yr and t0= –2.43 yr (n=86). Natural mortality was estimated at 0.17/yr. Age at maturity was estimated at 11 years for males and 15 years for females. Results of the demographic analysis showed that the population, in the absence of fishing mortality, was stable and not significantly different from zero and particularly sensitive to overfishing. At the current age at first capture and natural mortality rate, the fishing mortality rate required to result in negative population growth was low at F>0.004/ yr. Elasticity analysis revealed that juvenile survival was the principal factor in explaining variability in population growth rate.
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Date Issued: 2011

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Alleviating poverty and promoting sustainable livelihoods through implementing skills development programmes

- Mandavha, Ndovhatshinyani

Authors: Mandavha, Ndovhatshinyani
Date: 2011
Subjects: Poverty -- South Africa , Economic assistance, Domestic -- South Africa , Economic development projects -- South Africa , Poor -- Services for
Language: English
Type: Thesis , Masters , MA
Identifier: vital:9046 , http://hdl.handle.net/10948/1620 , Poverty -- South Africa , Economic assistance, Domestic -- South Africa , Economic development projects -- South Africa , Poor -- Services for
Description: Poverty alleviation projects are interventions designed to assist the socio-economic conditions of poor communities. This is a case study on a skills development project that has been implemented with the aim of alleviating poverty through equipping people with productive skills. The study was conducted in Lephalale, Limpopo province. It was conducted during July and August 2011. The study focuses on skills development as a poverty alleviation strategy because developing skills is essential for building human capacity. The study evaluates the effectiveness of skills development within a community that is characterised by lack of education and skills. Many rural communities fail to apprehend education and skills as a result of their location and poverty. They are isolated from cities and towns and this has an impact on their surrounding conditions including the level of skills and education. The study found that the skills development project in Lephalale played a vital role of developing skills through training community members with the skills necessary to obtain jobs and be able to create self-employment. Creating self-employment is one way to address the challenges of unemployment and the lack of income. There research found that there are various job opportunities being created in the area, however the local community cannot participate due to lack of skills required in the labour market. The study revealed the majority of the people who joined the skills development project did not complete grade 12 and have never worked.
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Date Issued: 2011

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An analysis of business skills and training needs in the plastic manufacturing industry in the Eastern Cape Province

- Macheke, Richard

Authors: Macheke, Richard
Date: 2011
Subjects: Plastics industry and trade -- South Africa -- Eastern Cape , Employees -- Training of -- South Africa -- Eastern Cape , Industrial management -- South Africa -- Eastern Cape , Success in business -- South Africa -- Eastern Cape , Vocational guidance -- South Africa -- Eastern Cape , Skilled labor -- South Africa -- Eastern Cape , Unskilled labor -- South Africa -- Eastern Cape , Labor turnover -- South Africa -- Eastern Cape
Language: English
Type: Thesis , Masters , M Com (Business Management)
Identifier: vital:11322 , http://hdl.handle.net/10353/d1007118 , Plastics industry and trade -- South Africa -- Eastern Cape , Employees -- Training of -- South Africa -- Eastern Cape , Industrial management -- South Africa -- Eastern Cape , Success in business -- South Africa -- Eastern Cape , Vocational guidance -- South Africa -- Eastern Cape , Skilled labor -- South Africa -- Eastern Cape , Unskilled labor -- South Africa -- Eastern Cape , Labor turnover -- South Africa -- Eastern Cape
Description: Skills development is one of the major challenges faced by South Africans, with more than 60 percent of the labour force being unskilled. This affects many industries around the country as are they forced to employ unskilled employees a development which has a negative bearing on the quality of products having a negative bearing on the quality of products. The Plastic Manufacturing Industry in the Eastern Cape Province is a prime example of firms that are affected by the short supply of skilled personnel on the labour market. Required skills range from business skills that are essential for the operating of a business, to technical skills that are essential for the employees who are involved in the production of goods and services. Training in skills has been proven to be a key to success. The primary objective of this study was to undertake an analysis concerning the significance of business skills and training needs for business success. Secondary objectives were to determine whether training in business skills as well as technical skills for the employees, could bring on success to the business. The study further went on to investigate the importance of training programmes for businesses. Research methodology included literature review and an empirical study, making use of the survey method through self-administered questionnaires. The statistical analyses included descriptive statistics, frequencies, Chi-square tests and linear regression and ANOVA. The Cronbach’s alpha was used to measure reliability of the research results. The research findings established that training in business skills and related types of skills was essential for the success of a business. The findings further showed that, due to training, there was improvement in sales, annual turnover, and product quality and employee skills. Recommendations included advice to invest in human capital through training which then should improve the quality of products. Further studies in other regions other than the Eastern Cape Province were recommended.
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Date Issued: 2011

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An analysis of Samuel P. Huntington's theories

- Kirkby, Daniela M

Authors: Kirkby, Daniela M
Date: 2011
Subjects: Liberalism , Politics and literature , Political science -- History
Language: English
Type: Thesis , Masters , MA
Identifier: vital:8271 , http://hdl.handle.net/10948/d1015964
Description: The traditional notion of Western liberal democracy has in recent years been met with a barrage of negative criticism. Liberal democracy from both a minimalist and substantive position appears to be backsliding, and once more falling into what Samuel P. Huntington (1991) termed a reverse wave. The analysis which Huntington (1991) presented ended in an era in which liberal democracy once more dominated the political landscape for a third consecutive wave, without any indication that it was going to relapse. In light of Huntington’s (1991) closure, this study has attempted to continue with his analysis and point to the possible existence of a third wave reversal. In order to do so, this study has meticulously used the same methodological approach as Huntington (1991) did to highlight previous wave reversals. This has been done by critically discussing, with examples, the existence of those factors that lead to a global decline in liberal democratic practice as prescribed by Huntington (1991). This study attempts not only to point to the possible existence of a third wave reversal, but also to explain the contextual reasons behind such an increase in anti-democratic rhetoric. The application of Huntington’s (1991) wave theory does not explain the subjective reasoning behind the contemporary deterioration of liberal democracy, as his factors leading to wave reversals may be too pragmatic for this study. It is in this light that a second argument as brought forward by Huntington in 1996, serves as the contextual layer for the decrease in democratic support as it provides the basis for the application of a critical discourse analysis. Therefore, this study serves not only as an investigation of the possible existence of a current third wave reversal, but also as an analysis into the discursive nature of liberal democracy’s historical and future trajectory.
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Date Issued: 2011

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An analysis of selected cartoons published during Zimbabwe's 2008 elections

- Mushohwe, Knowledge

Authors: Mushohwe, Knowledge
Date: 2011
Subjects: Zimbabwe. Parliament -- Elections, 2008 , World politics Caricatures and cartoons , Editorial cartoons -- Zimbabwe , Zimbabwe -- Politics and government -- 20th century , Mass media -- Law and legislation -- Zimbabwe , Freedom of speech -- Zimbabwe
Language: English
Type: Thesis , Masters , MTech
Identifier: vital:8493 , http://hdl.handle.net/10948/1609 , Zimbabwe. Parliament -- Elections, 2008 , World politics Caricatures and cartoons , Editorial cartoons -- Zimbabwe , Zimbabwe -- Politics and government -- 20th century , Mass media -- Law and legislation -- Zimbabwe , Freedom of speech -- Zimbabwe
Description: During Zimbabwe’s 2008 harmonised elections the country’s media laws had a direct impact on the way editorial cartoonists expressed themselves. Although the online newspapers were unregulated and the print media published under Zimbabwe’s media laws, Public Order and Security Act and Access to Information and Protection of Privacy act - the editorial cartoons from both sources show deliberate bias towards one candidate and contempt towards the main rival. The study contextualises the understanding of the editorial cartoon, as practised in an environment of freedom of speech and defined by the four categories identified by Press (1981) and Manning and Phiddian (2004), and delineates the effect of media laws on the newspaper industry in Zimbabwe. The four categories of editorial cartoons identified are descriptive editorial cartoons, laughing satirical editorial cartoons, destructive satirical editorial cartoons, and savage indignation editorial cartoons. The study reviews eight editorial cartoons, read using a semiotic framework investigating non-verbal communication, as defined and suggested by Du Plooy (1996), and a text and language grid, as suggested by Leech (1974), according to the criteria of symbols/metaphors, exaggeration/distortion, stereotypes, caricature, irony, captions, and background knowledge, as developed by Fetsko (2001). A comparative analysis of the cartoons reveals that objectives and functions of the unregulated zimonline.co.za and the regulated the Herald newspapers are the same. They constitute propagandistic representations of Zimbabwean politics that are more an extension of political ideology than they are a reflection of the country’s sociopolitical landscape.
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Date Issued: 2011

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An analysis of sources and predictability of geomagnetic storms

- Uwamahoro, Jean

Authors: Uwamahoro, Jean
Date: 2011
Subjects: Ionospheric storms Solar flares Interplanetary magnetic fields Magnetospheric substorms Coronal mass ejections Space environment Neural networks (Computer science)
Language: English
Type: Thesis , Doctoral , PhD
Identifier: vital:5451 , http://hdl.handle.net/10962/d1005236
Description: Solar transient eruptions are the main cause of interplanetary-magnetospheric disturbances leading to the phenomena known as geomagnetic storms. Eruptive solar events such as coronal mass ejections (CMEs) are currently considered the main cause of geomagnetic storms (GMS). GMS are strong perturbations of the Earth’s magnetic field that can affect space-borne and ground-based technological systems. The solar-terrestrial impact on modern technological systems is commonly known as Space Weather. Part of the research study described in this thesis was to investigate and establish a relationship between GMS (periods with Dst ≤ −50 nT) and their associated solar and interplanetary (IP) properties during solar cycle (SC) 23. Solar and IP geoeffective properties associated with or without CMEs were investigated and used to qualitatively characterise both intense and moderate storms. The results of this analysis specifically provide an estimate of the main sources of GMS during an average 11-year solar activity period. This study indicates that during SC 23, the majority of intense GMS (83%) were associated with CMEs, while the non-associated CME storms were dominant among moderate storms. GMS phenomena are the result of a complex and non-linear chaotic system involving the Sun, the IP medium, the magnetosphere and ionosphere, which make the prediction of these phenomena challenging. This thesis also explored the predictability of both the occurrence and strength of GMS. Due to their nonlinear driving mechanisms, the prediction of GMS was attempted by the use of neural network (NN) techniques, known for their non-linear modelling capabilities. To predict the occurrence of storms, a combination of solar and IP parameters were used as inputs in the NN model that proved to predict the occurrence of GMS with a probability of 87%. Using the solar wind (SW) and IP magnetic field (IMF) parameters, a separate NN-based model was developed to predict the storm-time strength as measured by the global Dst and ap geomagnetic indices, as well as by the locally measured K-index. The performance of the models was tested on data sets which were not part of the NN training process. The results obtained indicate that NN models provide a reliable alternative method for empirically predicting the occurrence and strength of GMS on the basis of solar and IP parameters. The demonstrated ability to predict the geoeffectiveness of solar and IP transient events is a key step in the goal towards improving space weather modelling and prediction.
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Date Issued: 2011

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An analysis of the elements of genocide with reference to the South African farmer's case

- Du Toit, Johanna Helena

Authors: Du Toit, Johanna Helena
Date: 2011
Subjects: Genocide -- South Africa , Human rights -- South Africa , Farmers -- South Africa
Language: English
Type: Thesis , Masters , LLM
Identifier: vital:10168 , http://hdl.handle.net/10948/1568 , Genocide -- South Africa , Human rights -- South Africa , Farmers -- South Africa
Description: The definition of genocide encompasses not only the killing of a protected group as is so often erroneously believed, but also inter alia the causing of serious bodily and mental harm to a group and deliberately inflicting conditions of life on a group calculated to bring about its destruction in whole or in part. Eight stages have been identified through which conventional genocide goes. There is a closed list of four groups named in the Genocide Convention in respect of which genocide can be perpetrated. Problems have been experienced with the classification and the determination whether a group should qualify or not. In answer to this problem, the definition of the groups should be seen cohesively and attempts should preferably not be made to compartmentalise any group suspected of being targeted for genocide. The special intent required for genocide sets it apart from other crimes against humanity. The intention that needs to be proven is the desire to exterminate a group as such in whole or in part. The mention of “in part” opens the door for genocide to be perpetrated against a small sub-group which conforms to the definition of a group. The white Afrikaner farmer forms part of the larger white Afrikaner group residing in South Africa. Incitement to genocide is an inchoate crime and is regarded as a lesser crime reflected in lower sentences being passed for incitement than for genocide itself. The requirements are that the incitement must be direct and public. The required intention to incite must also be proven for a conviction to follow. The farmer who laid the complaint with the International Criminal Court, did so in the hope that the Prosecutor would utilise his or her proprio motu powers to instigate an investigation in South Africa regarding white Afrikaner farmers. The complaint and petition as well as the statistics used by the farmer paint the picture of incitement to genocide and possible genocide. The allegations are not specific and will have to be proven in a court of law for any such finding to follow. , Abstract
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Date Issued: 2011

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An analysis of the factors influencing the provision of water in the Buffalo City Municipality, province of the Eastern Cape

- Zwelibanzi, Mantombi Elizabeth

Authors: Zwelibanzi, Mantombi Elizabeth
Date: 2011
Subjects: Water-supply -- South Africa -- Buffalo City , Municipal services -- South Africa -- Eastern Cape
Language: English
Type: Thesis , Masters , MA
Identifier: vital:8260 , http://hdl.handle.net/10948/d1013011
Description: Factors affecting the provision of water constitute a great challenge to water officials not only in Buffalo City Municipality but also globally. Interviews form the basic data collection instrument used to provide empirical evidence to the objectives of the study. The objectives of the study are: To evaluate the underlying challenges encountered by water sector Engineers; To evaluate the role of municipal water sector officials in the provision of clean water; To analyse the factors influencing the provision of water in Buffllo City Municipality. Recommendations are provided which could assist Buffalo City Municipality in addressing the challenges affecting the provision of water as follows: The involvement of national and provincial governments in order to improve the Buffalo City Municipal infrastructure and capacity building is highly recommended. Power failure and water interruptions caused by mechanical problems and natural disasters, are further municipal challenges that need to be addressed irrespective of financial constraints. Public and private sector sponsors can be approached to join the initiative. Informal settlements should be formalised and limited to a certain number of people per site or household, depending on the infrastructure. If the infrastructure is not conducive they should be relocated elsewhere. Public and private sector sponsors should offer assistance to Buffalo City Municipality to develop the required water skills, by financing water officials who are interested in furthering their education at tertiary level. Public consultation, through meetings and public forums, and public participation, by the street committees and police forums, are recommended. Coupon systems for basic services like water and electricity for all residents is highly recommended. A generator for the municipal water sector is needed. This will overcome the power failure problem. The provision of water is affected by power outages as water equipment needs electricity to be able to operate. Installation of a water plant in Buffalo City Municipality‟s main dam, the Maden dam, that is supposed to supply King Williams town and the surrounding areas directly.
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Date Issued: 2011

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An analysis of the influence of domestic macroeconomic variables on the performance of the South African stock market sectoral indices

- Hancocks, Ryan Lee

Authors: Hancocks, Ryan Lee
Date: 2011
Subjects: Johannesburg Stock Exchange , Stock price indexes -- South Africa , Interest rates -- South Africa , Macroeconomics -- Econometric models
Language: English
Type: text , Thesis , Masters , MCom
Identifier: vital:954
Description: An econometric study was undertaken to determine the extent to which selected macroeconomic variables influenced stock market prices on the All-Share, Financial, Mining and Retail Indices of the Johannesburg Stock Exchange in South Africa from 1996:7 to 2008:12. The Johansen cointegration method was used to determine whether cointegrating relationships existed between the macroeconomic variables and the stock market indices. A Vector Error Correction model was estimated and found significant results that money supply, inflation, long and short- run interest rates, and the exchange rate all had an influence on stock market prices. Further, the VECM results for each sector indicated that certain macroeconomic variables had differing influences on each sector of the stock market. Impulse Response tests indicated that the selected macroeconomic variables caused shock to the sectoral indices in the short-run but that the effect was lagged. The Variance Decomposition tests conducted supported earlier evidence that the macroeconomic variables had a strong level of sectoral index determinacy in the long run. The results found that the All-Share and Financial Indices were negatively influenced by inflation and short term interest rates in the long run, while the Financial Index also had a negative relationship with long-run interest rates. Money supply was found to have a positive effect on all the indices. A weakening of the exchange rate was found to have a positive influence on both the Retail and Mining Indices, while it negatively affected the All-Share and Financial Indices. The long-run interest rate had a positive influence on both the Retail and Mining Indices. Overall the study finds that macroeconomic variables are important determinants of stock market prices in South Africa and that it is important to examine each sector of the stock market separately to capture what are different effects. The limitations of the study are that a different measure for exchange rates from the nominal rand/dollar exchange rate used here may yield more decisive results and provide insight into the link between exchange rate behaviour and performance of especially the retail sector.
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Date Issued: 2011

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