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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Addressing the expectations gap between corporate environmental performance communication and an affected community’s needs : with reference to organisations situated in markman township and the residents of Bluewater Bay, Port Elizabeth

Williams, Brett January 2014 (has links)
The purpose of this study was to identify and address an expectations gap in the environmental-performance information between a community that believes it is being polluted and the organisations from a nearby industrial area. The study has consisted of a literature survey and a field study. The field study comprised a survey among the residents in Bluewater Bay, and a similar survey amongst the organisations in Markman Township. These areas were chosen because there is a history of community complaints on the pollution from the Markman Township organizations. The field study was designed to test the following:  The first aim of the study was to identify whether an expectations gap exists between the organisations and the community. This gap relates to environmentalperformance information to which the community believes it should rightfully have access, and the information that the organisations are willing to provide. The second aim of the study was to determine what type of information the community requires when it believes it is being polluted or affected negatively.  Thirdly, what methods of communication the community believe would be effective when organisations share environmental-performance information. In a review of the literature, the theoretical and legal drivers for assessing environmentalperformance reporting were identified. The questionnaires were designed to test the notion that communities are legitimate stakeholders of organizations. The field study also attempted to identify whether the Markman Industrial Township organisations had used symbolic or substantive legitimacy strategies to improve their legitimacy among the residents. The prior literature identifies various types of environmental information that organisations should report publicly. A list of the communication methods for disclosing the information was identified. The support for these methods was measured in the community and among the companies in Markman Industrial Township. The results indicated that there is an expectations gap between the community and the organisations, as there was a statistically significant difference in the responses between the two respondent groups on the types of information that the community requires. The five types of information needs that had the most community support were:  The amount and type of chemical spills emanating from each organization.  The amount and type of hazardous and non-hazardous waste generated.  The amount and type of air emissions from each organization.  The amount and type of liquid effluent discharged to the sewer.  Incidents of non-compliance with environmental laws and regulations. The above types of information relate to physical pollution and to regulatory compliance with the stipulated legal requirements. Furthermore, the companies did not regard the community as legitimate stakeholders; and they did not believe that their operations affected the environment in a significant manner. The five most favoured communication methods preferred by the community respondents, in descending order of preference, are:  Newsletters,  Formal environmental reports,  Newspaper feature articles,  Letters to residents, and  News releases. The community supported all the methods of communication that were presented and indicated a preference for non-verbal communication methods. The organisations likewise indicated a preference for non-verbal methods of communication. The study is important, as it provides companies with insight into the communications needs of local communities and specifically their preferred methods to receive environmentalperformance information. Secondly, South African legislation contains various rights that citizens have in terms of a healthy and safe environment, as well as access to information where their Constitutional rights may be infringed. The results of the study could assist companies to go beyond legal compliance in their environmental performance, by addressing local community concerns in a way that will positively impact their ability to maintain legitimacy. / Thesis (PhD)--University of Pretoria, 2014. / tm2015 / Zoology and Entomology / PhD / Unrestricted
72

The development of social behaviour in translocated juvenile African elephants Loxodonta africana (Biumenbach)

Garai, Marion Elizabeth January 1997 (has links)
Groups of translocated orphaned juvenile African elephants were studied in holding pens and following their release to assess how they re-organize and restructure socially by adopting roles, and if they show behavioural signs of stress. An adult female adopted a young individual. In all groups allomothering was observed to some degree. One 5 year old female prematurely assumed the role of leader and this role appears to be learned. Most groups established a linear dominance hierarchy. Placing the trunk tip into a partner's mouth correlated with play-fighting and aggression. This behaviour is suggested to be one of appeasement to reduce aggressive motivation and prevent escalation thereof, and that the behaviour is ritualised. Four possible evolutionary steps are presented. Nearest Neighbour analyses illustrated the changing social positions of some juveniles relative to other individuals. Tight grouping was assumed to indicate insecurity. There was a marked difference in behaviour pattern during resting times. Groups without adults were within touching distance of one another whilst resting. In a group containing an adult female some juveniles dispersed more and some juveniles formed a subgroup. It appears that dominance hierarchies, individual social relationships and caretaking of young were important factors which affected group cohesion and could influence a more central position within a group. Certain behaviour patterns were defined as being stress related and compared among the groups. There was a significant decrease in arousal behaviour after the introduction of an adult female. Aggressive behaviour was the most frequent behaviour in four groups whilst penned and following their release. Play behaviour was absent in three penned groups, and tended to gradually increase following the release. Temporal gland secretion occurred during excitement, anticipation and nervousness. Secretion occurred in all age and sex classes. Females tend to secrete more frequently than males and older individuals more than younger ones. Frustrated or stressed animals vocalized more frequently than relaxed ones, as did calves below 2 years of age who tended to use louder calls, than older juveniles. Acoustical analyses of four vocalizations are presented. Very young individuals appear to vocalize using marginally higher frequencies. / Dissertation (MSc)--University of Pretoria, 1997. / Zoology and Entomology / MSc / Unrestricted
73

Understanding barriers to entry into the vertically integrated oil industry and applying economic theories of entry into this industry

Sihlobo, Lwazi January 2017 (has links)
Barriers to entry are one of the critical forces that provide incumbent firms with competitive advantage over new entrants and contribute to an oligopoly market structure. The aim of this research was to determine barriers to entry into the vertically integrated oil industry and identify economic theories of entry into the market and apply them to the South African vertically integrated oil industry. A mixed method design was adopted to conduct this research. A 5-point Likert scale questionnaire with statement of barriers to entry obtained from literature was sent out to middle and senior managers of vertically integrated oil firms and non-refining oil wholesalers. Semi-structured interviews of middle and senior managers in the oil industry; regulatory body and industry associations were conducted to gain insights in the industry challenges and those challenges facing small firms. Emerging themes from interview results were analysed on the backdrop of research propositions. Similarly, quantitative results obtained from the survey were analysed based on the hypotheses and contrasted with qualitative results. The findings indicated that there are significant barriers to entry in the oil industry and affect both vertically integrated (refining and marketing) oil firms and non-refining oil wholesalers. However, non-refining oil wholesalers were impacted more negatively by the barriers to entry due to high capital requirements, lack of access to infrastructure, lack of access to capital and regulatory pricing model (RAS). Results also showed that oil firms put different emphasis of importance to different barriers of entry. / Mini Dissertation (MBA)--University of Pretoria, 2017. / zk2017 / Gordon Institute of Business Science (GIBS) / MBA / Unrestricted
74

The long-run performance of initial public offerings on the Johannesburg Stock Exchange

Snyman, Wynand January 2017 (has links)
This report examines the long-run performance of Initial Public Offerings on the Johannesburg Stock Exchange. The primary objective is to calculate the cumulative average abnormal returns using simpler models such as a market model or a single parameter CAPM and then to introduce a risk adjusted style model to determine whether the significant returns would disappear. These risk factors include the size of the firm, a value versus growth factor as well as an adjustment for the resource focussed Johannesburg Stock Exchange. The secondary objective of this report is to calculate the returns of event firms engaging either a prestigious underwriter or those that do not as well as the calculation of the returns of large firms and non-large firms. Event study methodology was used on the 48 Initial Public Offerings on the Johannesburg Stock exchange from 01 January 2006 to 31 May 2016 that formed part of the All Share Index. The study determined the cumulate average abnormal returns over a 36 month period after the event date and was tested at the 5% level of significance through the use of a Monte Carlo bootstrap simulation. The results show that the cumulative average abnormal returns found using simpler methods were in fact significant and that these significant returns disappear when a risk adjusted style model was introduced. Further, the results showed that using either a prestigious underwriter or a non-prestigious underwriter yields insignificant cumulative average abnormal returns and / Mini Dissertation (MBA)--University of Pretoria, 2017. / sn2017 / Gordon Institute of Business Science (GIBS) / MBA / Unrestricted
75

The equity market impact of SA's transition from STC to dividend withholding tax : an event study

Visser, Ernie January 2017 (has links)
For over 50 years academics have grappled with trying to understand and quantify the influence of dividend taxes on the behaviour of equity markets. As a shareholder, one should rationally be indifferent to receiving returns in the form of dividend payouts or value growth. Markets are, however, not perfectly efficient and investors are not completely rational. The purpose of this research project was to analyse and quantify the impact on the behaviour of South Africa's equity market, if any, resulting from the decision to replace the Secondary Tax on Companies system with the Dividend Withholding Tax regime at a higher effective tax rate. An events study methodology that was quantitative and causal in nature was used to test five hypotheses for three separate events that collaboratively indicate whether there was an impact from this change in dividend regulation or not. The results align with empirical evidence from international literature and indicate that there was indeed a significant, negative equity market impact resulting from the transition. The negative reaction is primarily attributable to the hike in the dividend tax rate rather than the reduction in regulatory complexity and was shown to be more significant for higher dividend yield firms. / Mini Dissertation (MBA)--University of Pretoria, 2017. / zk2017 / Gordon Institute of Business Science (GIBS) / MBA / Unrestricted
76

Characterization of efflux pumps genes involved in second-line drug resistance of tuberculosis

Malinga, Lesibana Anthony January 2017 (has links)
In this study, we used molecular and proteomic methods to detect novel changes within drug-resistant tuberculosis (TB) strains. Our goal was to detect changes within efflux pump (EP) genes of extensively drug resistant (XDR-TB) strains using genomic and transcriptomic methods. We firstly sequenced multiple genes in discordant samples that lacked molecular markers present on the GenoType® MTBDRsl assay. Further analysis by whole genome sequencing was done on XDR-TB strains. Transcriptomic changes of EP genes were detected by RNA sequencing strains. The minimum inhibitory concentration (MIC) of second-line drugs in the presence and absence of efflux pump inhibitors was also measured. Proteomic expression by cloning and expression of three efflux pump genes (Rv1258c, Rv1634 and Rv0194) was done and effect on MICs of second-line drugs measured in the presence and absence of efflux pump inhibitors. We analysed molecular markers responsible for resistance to second-line drugs of ofloxacin (OFX), amikacin (AMK), kanamycin (KAN) and capreomycin (CAP) in 636 drug-resistant strains using GenoType® MTBDRsl. We compared GenoType® MTBDRsl with phenotypic second-line drug susceptibility testing. After comparison, 102 (14.8%) strains were discordant between the two methods. In the discordant population, genetic regions of gyrA, gyrB, rrs, eis, tlyA and EP genes (Rv1634, Rv1258c and Rv0194) were sequenced and analysed in search of mutations. Combining sequencing and GenoType® MTBDRsl significantly improved the diagnosis of XDR-TB and second-line drugs. The Rv0194 belongs to the ATP (adenosine triphosphate) binding cassette (ABC) family while Rv1258c and Rv1634 belong to the major facilitator superfamily (MFS) transporters. Since these genes are implicated in multiple drug resistance, our hypothesis was that possible mutations in these genes could confer cross-resistance. Our analysis revealed the appearance of Rv1258c and Rv0194 mutations in strains with cross-resistance to second-line injectable drugs. Further analysis revealed rrs G878A mutation that was specific to EuroAmerican X3 lineage (P<0.001) and linked to CAP resistance. The inclusion of G878A in new rapid assays might be beneficial for rapid CAP resistance detection. Whole genome sequencing with increased resolution and depth was used to study two XDR-TB strains. Drug resistant mutations were detected for all other drugs except for OFX in one strain. We further analysed EP genes for mutations. Bioinformatic prediction tools detected protein changes related to EP gene mutations belonging to Rv0987, Rv2039 and Rv0402. Two of the efflux pump genes (Rv0987, Rv2039) belong to the ABC family, while Rv0402 is of resistance nodulation-cell division (RND) family. Mutations within lipid metabolism and secretion pathways were also detected. To fully understand the role of EP gene mechanisms at a transcriptional level, we sequenced RNA molecules of 11 XDR-TB, five MDR and two susceptible strains. The RNA signatures of EP and lipid metabolism genes detected in XDR-TB strains were characterized. Further analysis of four XDR strains with MIC data with or without efflux pump inhibitors (EPIs) was performed in relation to RNA sequenced data. The ABC Rv2686/87/88c operon was significantly over-expressed in the background on strains with gyrA mutations causing OFX resistance. The Rv1258c, Rv0194 and Rv1634 EP genes were consistently over-expressed in XDR TB strains. Efflux pump inhibitor of piperine was effective in reducing MICs to hydrophilic drugs of AMK and OFX whereas verapamil reduced MIC of hydrophobic CAP drug. Protein-protein interaction pathways revealed novel associations between ABC, RND and type VII secretion (T7S) proteins. Finally, we cloned and expressed Rv1258c, Rv0194 and Rv1634 EP genes in Mycobacterium vectors. These genes have the potential to cause multidrug resistance. We did not detect increased MIC levels of second-line drugs in the presence of the clones. However, a reduction of MICs in the presence of the EPI, piperine, was observed. Bioinformatic approaches also revealed transmembrane motifs, domains and loops. Since EP genes are implicated in transport of substrates across cell membrane, we used biofilm formation assays to determine the role of each clone. Both Rv1258c and Rv0194 clones showed biofilm formation. Such discovery highlights the secretion of lipid bodies on the cell wall of the bacteria through EP genes/proteins. This information will allow us to develop novel strategies to treat drug-resistant TB. Our study emphasises the importance of EP gene mechanisms in causing drug resistance. The combination of EP and target genes is important in the detection of second-line drugs. Furthermore, it is suggested that EPIs combined with second-line drugs might be effective in the treatment of XDR-TB. / Thesis (PhD)--University of Pretoria, 2017. / Internal Medicine / PhD / Unrestricted
77

Trichomonas vaginalis and bacterial co-infections identified in reproductive age women

Sethowa, Jonas Tshoene January 2017 (has links)
Sexually transmitted infections (STIs) continue to be a significant public health problem with an increased burden on women of reproductive age. These infections can be transmitted between humans by means of sexual activity including vaginal intercourse, oral sex and anal sex. Having a STI increases the risk of acquiring human immune-deficiency virus (HIV), hence the control of STIs is recommended for HIV prevention. The most common STI disease presentations to the public health setting in South Africa are male urethritis syndrome (MUS) and vaginal discharge syndrome (VDS). The main pathogens responsible for these two syndromes are: Chlamydia trachomatis, Neisseria gonorrhoeae and Trichomonas vaginalis. In the late 1990s the South African health department introduced the STI syndromic management approach into the primary health care setting. This approach aims to treat the common causes of STI syndromes through the use of specific treatment algorithms. It is cost effective because it allows treating the majority of STI patients without the need of laboratory diagnosis to determine the aetiological agent. People without any clear symptoms will remain untreated by the syndromic management approach. Little is known of the STI pathogens circulating in reproductive age women in the Tshwane region. The purpose of this study was to determine the prevalence of T. vaginalis and its co-infection in reproductive age women. This study included self-collected vaginal swabs obtained from 117 consenting reproductive age women visiting either a public health clinic or a sexual private health clinic. The swabs were cultured upon receipt in the laboratory on chocolate agar and in the InPouchTV for detection and diagnosis of N. gonorrhoeae and T. vaginalis respectively. The Nugent scoring system was used to diagnose bacterial vaginosis. The STI causing pathogens were detected on different molecular platforms which included Anyplex II STI-7 real-time PCR, GeneXpert CT/NG and GeneXpert TV. The overall prevalence for both clinics of STIs was 13.7% (16/117) and for T. vaginalis specifically, a 10.3% (12/117) rate was observed. A co-infection rate of 2.6% (3/117) was observed in this study. Trichomonas vaginalis occurred mostly with C. trachomatis (12.5%) followed by N. gonorrhoeae (6.3%). Most co-infections were observed in women of younger than 30 years old. Age was not significantly associated with the prevalent T. vaginalis infection in this study but being unmarried showed a significant association (p-value=0.038) with the prevalent infection in both clinics. The high rates of Trichomonas vaginalis and coinfections with C. trachomatis and N. gonorrhoeae observed in the asymptomatic women visiting the two clinics provide evidence that in certain key groups the simultaneous screening for all three pathogens should be performed. / Dissertation (MSc)--University of Pretoria, 2017. / Medical Microbiology / MSc / Unrestricted
78

The role of the academic library in supporting distance education through the use of information and communication technology : the Open University of Tanzania

Venance, Charles January 2016 (has links)
ABSTRACT This study focuses on the role of the academic library in supporting distance education through the use of information and communication technology, focusing on the Open University of Tanzania. The study entailed a number of objectives: To examine the information and computer mediated library services needed by the distant learners at the Open University of Tanzania Library, to find out the perceived quality of services offered by the Open University of Tanzania Library to support distance education through the use of ICT, to find out the extent to which the academic libraries embrace/apply ICT to offer library services, to examine the challenges encountered by the Open University of Tanzania Library to support distance education through the use of ICT and to suggest strategies that should be adopted to overcome the challenges at the Open University of Tanzania Library to support distance education through the use of ICT. As regards data collection, questionnaires and focus group interviews were used. The study used a sample of 100 out of 472 students from the faculty of education and 5 librarians out of 15 librarians. This included a total of 105 out of 487. The respondents to be selected included undergraduate and post graduate students. Data analysis involved a set of qualitative and quantitative methods. Qualitative data obtained from the study was coded and grouped into themes pertaining to the study questions, ideas, opinions and recommendations by the individuals. Findings indicate that there are issues that need to be addressed as regards the effective use of the internet in accessing information, the improvement of ICT related infrastructures, space in the library, and effective implementation of the policies in place to address the challenging issues. Moreover, findings suggest that there is a need to raise computer literacy among library users as well as encouraging inter-library loan among the academic libraries. / Mini Dissertation (MIT)--University of Pretoria, 2016. / CARNEGIE COOPERATION OF NEW YORK / Information Science / MIT / Unrestricted
79

The role of the University of Cape Town Libraries in support of researchers’ scholarly use of social media

Dunlop, Janine January 2015 (has links)
Social media tools are widely used by the public at large. In recent years, they have been employed by researchers and academics to connect with each other, discuss their research, gather data, and share resources. Mainstream tools such as Facebook, Twitter, and Google+ have been joined by tools custom-made for researchers, such as ResearchGate, Academia.edu and FigShare. This study sought to explore whether social media tools were being used by researchers at the University of Cape Town (UCT) and if so, how they were being employed within the research process. The overarching question that the study aimed to answer was whether the UCT Libraries could support the use of social media by researchers at the University and if so, how this should be done. The study adopted a mixed methods approach. Questionnaires gathered primarily quantitative data, while interviews gathered qualitative data and augmented the data gathered via the questionnaires. Respondents were asked to provide details of their use of social media during the research process, or lack thereof, and to offer their suggestions for how the Library could support this activity. It was found that social media is being used during the research process by the respondents to the study in a variety of ways. Respondents provided insight into drivers and hindrances to the use of social media for this purpose. The UCT Library has a part to play in supporting this activity, specifically through training, information, and consultation sessions, and by understanding the types of social media users at the University, their social media needs, and their perceptions of social media. / Mini Dissertation (MIT)--University of Pretoria, 2015. / Information Science / MIT / Unrestricted
80

Development-induced displacement in Africa : striking a balance between the imperative of development and the rights of persons likely to be displaced

Adeola, Romola January 2015 (has links)
Recognising the need to tackle the root causes of internal displacement, African leaders in 2009 adopted the first binding treaty on internal displacement, the African Union Convention for the Protection and Assistance of Internally Displaced Persons in Africa (the Convention). The Convention entered into force on 6 December 2012. As at January 2015, 39 states have signed the Convention, 23 of which have ratified. One of the root causes of internal displacement recognised in the Convention is development-induced displacement (DID). This root cause of internal displacement is the focus of this thesis. Under article 10(1) of the Convention, states are obligated as much as possible? to prevent displacement caused by development projects. This thesis argues that this obligation must necessarily be construed in light of the Convention?s overall emphasis on the prevention of arbitrary displacement. The prevention of arbitrary DID necessarily implies that a balance has to be struck between the imperative of development and the rights of persons likely to be displaced. In striking this balance, this thesis applies the means-end test of proportionality arguing that a development project must be suitable and be the least instrusive of rights. Further, the obligation on states to prevent DID as it relates to private actors, specifically corporations, is discussed. This thesis argues that in regulating corporations, state parties to the Convention should adopt a common regulatory standard detailing the corporate duty to respect human rights within the context of article 10 of the Convention. On an institutional level, national institutional mechanisms can be utilised in striking the balance between the imperative of development and the rights of persons likely to be displaced. While acknowledging that each state party has the primary obligation to realise the Convention?s obligations, mechanisms beyond the state such as the Conference of State Parties and the African Commission on Human and Peoples? Rights (the African Commission) have crucial roles to play in furthering compliance with the obligation in the Convention. This thesis recommends that the Conference of State Parties should adopt a Model Law specifically dealing with article 10 of the Convention; and that the African Commission should: (a) develop a General Comment on article 10; (b) revise its guidelines on state reporting to ensure that states report on the obligation in the Convention; and (c) conduct missions to states where development projects, likely to result in displacement, are to be implemented. / Thesis (LLD)--University of Pretoria, 2015. / tm2016 / Centre for Human Rights / LLD / Unrestricted

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