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Analysis of calendar effects and market anomalies on the Johannesburg Stock Exchange

  • Authors: Atsin, Achiapo Jessica Lisette
  • Date: 2015
  • Subjects: Stock exchanges -- South Africa -- Johannesburg , Stocks -- South Africa
  • Language: English
  • Type: Thesis , Masters , MCom
  • Identifier: vital:9028 , http://hdl.handle.net/10948/d1020372
  • Description: This study sought to empirically investigate the existence of calendar effects and market anomalies on the JSE using monthly and daily closing prices of the ALSI, Top 40, Mid Cap and Small Cap index; as well as, daily closing prices on the Value, Growth and Dividend Plus index during the sample period 2002 – 2013. The anomalies analysed are the January effect, the weekend effect, the size effect, the value effect, and the dividend yield effect. The empirical analysis uses a number of MSAR with a different number of regimes and lag orders. The results from the investigation of the January effect show the non-existence of the January effect and the value effect on the JSE during the periods 2002 – 2013 and 2004 – 2013, respectively. However, the weekend effect was found significant in the Mid Cap and the Small Cap index, and the size effect was also found significant during the same period 2002 - 2013. Finally the results from a Granger causality test concluded that there is a relationship between the returns on the Dividend Plus index and the ALSI, effectively proving the existence of the dividend yield effect on the JSE between 2006 and 2013. Additionally, the anomalies found imply the opportunity for investors to make returns above buy-and-hold.
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  • Date Issued: 2015

Analysis of predictive power of binding affinity of PBM-derived sequences

  • Authors: Matereke, Lavious Tapiwa
  • Date: 2015
  • Subjects: Transcription factors , Protein binding , DNA-binding proteins , Chromatin , Protein microarrays
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4161 , http://hdl.handle.net/10962/d1018666
  • Description: A transcription factor (TF) is a protein that binds to specific DNA sequences as part of the initiation stage of transcription. Various methods of finding these transcription factor binding sites (TFBS) have been developed. In vivo technologies analyze DNA binding regions known to have bound to a TF in a living cell. Most widely used in vivo methods at the moment are chromatin immunoprecipitation followed by deep sequencing (ChIP-seq) and DNase I hypersensitive sites sequencing. In vitro methods derive TFBS based on experiments with TFs and DNA usually in artificial settings or computationally. An example is the Protein Binding Microarray which uses artificially constructed DNA sequences to determine the short sequences that are most likely to bind to a TF. The major drawback of this approach is that binding of TFs in vivo is also dependent on other factors such as chromatin accessibility and the presence of cofactors. Therefore TFBS derived from the PBM technique might not resemble the true DNA binding sequences. In this work, we use PBM data from the UniPROBE motif database, ChIP-seq data and DNase I hypersensitive sites data. Using the Spearman’s rank correlation and area under receiver operating characteristic curve, we compare the enrichment scores which the PBM approach assigns to its identified sequences and the frequency of these sequences in likely binding regions and the human genome as a whole. We also use central motif enrichment analysis (CentriMo) to compare the enrichment of UniPROBE motifs with in vivo derived motifs (from the JASPAR CORE database) in their respective TF ChIP-seq peak region. CentriMo is applied to 14 TF ChIP-seq peak regions from different cell lines. We aim to establish if there is a relationship between the occurrences of UniPROBE 8-mer patterns in likely binding regions and their enrichment score and how well the in vitro derived motifs match in vivo binding specificity. We did not come out with a particular trend showing failure of the PBM approach to predict in vivo binding specificity. Our results show Ets1, Hnf4a and Tcf3 show prediction failure by the PBM technique in terms of our Spearman’s rank correlation for ChIP-seq data and central motif enrichment analysis. However, the PBM technique also matched the in vivo binding specificities of FoxA2, Pou2f2 and Mafk. Failure of the PBM approach was found to be a result of variability in the TF’s binding specificity, the presence of cofactors, narrow binding specificity and the presence ubiquitous binding patterns.
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  • Date Issued: 2015

Androcentrism and misogyny in late twentieth century rock music

  • Authors: Berkland, Darren Gary
  • Date: 2015
  • Subjects: Music -- Social aspects , Gender identity in music , Music -- Performance -- Psychological aspects , Emotions in music , Rock musicians
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:8440 , http://hdl.handle.net/10948/d1021199
  • Description: Judith Butler’s writings on gender ostensibly changed the way gender is considered with regard to an individual’s subjectivity. Her writings expressed a discursive parameter that changed the theoretical standpoint of gender from that of performance, to that of performativity. In short, the notion of gender became understood as a power mechanism operating within society that compels individuals along the heteronormal binary tracts of male or female, man or woman. Within the strata of popular culture, this binarism is seemingly ritualized and repeated, incessantly. This treatise examines how rock music, as a popular and widespread mode of popular music, exemplifies gender binarism through a notable ndrocentrism. The research will examine how gender performativity operates within the taxonomy of rock music, and how the message communicated by rock music becomes translated into a listener’s subjectivity.
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  • Date Issued: 2015

Antibiotic stewardship: the role of clinical pharmacist

  • Authors: Ramkhalawon, Shabeerah
  • Date: 2015
  • Subjects: Hospital pharmacies -- South Africa Pharmacists -- South Africa
  • Language: English
  • Type: Thesis , Masters , MPharm
  • Identifier: http://hdl.handle.net/10948/10858 , vital:26830
  • Description: South Africa has a high prevalence of infectious diseases; the major ones being the Human Immunodeficiency Virus/Acquired Immune Deficiency Syndrome epidemic, and tuberculosis. South Africa’s burden of resistant bacteria is also increasing. Antibiotic resistance in hospitalised patients leads to an increase in morbidity and mortality, resulting in longer hospital stays, and an increase in hospital costs. In order to counteract the problem of antibiotic resistance in hospitals and other healthcare facilities and preserve the efficacy of currently available antibiotics, there is a need for serious antibiotic management. Antibiotic stewardship initiatives have thus been put in place to guide healthcare professionals on the correct use of antibiotics. Clinical pharmacists can intervene and contribute to antibiotic stewardship owing to comprehensive knowledge of antibiotics, including the properties, uses, safety and efficacy of individual agents. There is a paucity of research to support the role of the clinical pharmacist in antibiotic stewardship in public sector hospitals. The current pharmacist staffing system within public sector hospitals does not adequately support pharmacists, in particular clinical pharmacists, to participate actively in antibiotic stewardship. The primary aim of the study was to evaluate the role of the clinical pharmacist in antibiotic stewardship in a public hospital setting. A secondary aim was to contribute towards more rational inpatient use of antibiotics in the general medical ward. The hypothesis for the study was that clinical pharmacists can make a positive contribution to the correct use of antibiotics in a public hospital setting. The study showed that the introduction of a pharmacist-driven antibiotic stewardship in the ward, using a prospective audit and feedback strategy, had a positive effect on overall appropriateness of antibiotic prescribing (Chi2=7.89; df=3; p=0.04815, Cramer’s V=0.13). However, this finding did not show any reduction in the volume of antibiotic use. Positive patient outcomes were achieved and shown through a reduction in the length of hospital stay (p=0.00487; one-way ANOVA). Although patients were not followed up on discharge to assess re-admission rates, the results are relevant in order to inform the hospital staff about the implementation of antibiotic stewardship at the public hospital setting with the aims of reducing inappropriate antibiotic prescribing and improving patient outcomes. From the results of the study, it can be concluded that the hypothesis was achieved and that the clinical pharmacist did play an integral role in antibiotic prescribing at the public hospital setting. Thus, it can be concluded that the study, though limited in its scope, achieved its aims and objectives, and showed that the clinical pharmacist does play an integral role in the rational use of antibiotics in a public hospital setting.
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  • Date Issued: 2015

Antjie Krog and the post-apartheid public sphere: Speaking poetry to power

  • Authors: Garman, Anthea
  • Date: 2015
  • Language: English
  • Type: text , book
  • Identifier: http://hdl.handle.net/10962/159913 , vital:40355 , ISBN 978-1869142933
  • Description: Antjie Krog has been known in Afrikaans literary circles and the media for decades because of her poetry and her strong political convictions. Often known simply as 'Antjie,' she is also affectionately called 'our beloved poet' and our 'Joan of Arc' by Afrikaans commentators. It was through her work on the Truth and Reconciliation Commission as an SABC radio journalist and her subsequent book, Country of My Skull, that Antjie Krog then became known to English-speakers in South Africa and across the world. Her work catapulted her particular brand of poetics and politics, honed over many years of her opposition to apartheid, into the South African public sphere at a time when the country was not only looking for a humane and just resolution after the apartheid era, but was also establishing itself as a new democracy.
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  • Date Issued: 2015

Anton and Vale van der Merwe: reinterpreting Afro-Oriental studio ceramics traditions in South Africa

  • Authors: Steele, John
  • Date: 2015
  • Language: English
  • Type: text , Article
  • Identifier: http://hdl.handle.net/11260/968 , vital:30077
  • Description: Growing awareness of ancient Chinese Song and Yuan ceramics, amongst other Oriental traditions, by people with western connections such as Bernard Leach and Michael Cardew, in conjunction with influences from Japanese associates such as Soyetsu Yanagi, Kenkichi Tomimoto, and Shoji Hamada, (De Waal 1997, Harrod 2012, Kikuchi 1977, Leach 1976) has had many consequences. It spread a consciousness idealizing self-sufficient pottery studios where potters were in touch with all aspects of creating utilityware, largely from local materials for local use. Out of this emerged an Anglo-Oriental studio ceramic philosophy of form and practice, associated mainly with hand-made high temperature reduction fired ceramics. These ideas spread to South Africa in the late 1950s, and by the early 1960s local studios were being established along these lines. This studio ceramics movement grew exponentially in South Africa, initiating a phase of Afro-Oriental ceramics that remains a powerful way of life and visual arts influence. This paper seeks to explore aspects of Afro- Oriental studio ceramics in South Africa, with particular reference to the Leach/Hamada/Cardew to Rabinowitz, and Van der Merwe lineage.
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  • Date Issued: 2015

Application of bacteriocins in the preservation of fruit juice

  • Authors: Bodley, Mark David
  • Date: 2015
  • Subjects: Bacteriocins , Fruit juices -- Preservation
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:10345 , http://hdl.handle.net/10948/d1020188
  • Description: Bacteriocins (BCNs) are ribosomally synthesized polypeptides or proteins with antimicrobial activity, produced by different groups of bacteria. Many lactic acid bacteria (LAB) produce BCNs with broad spectra of inhibition. The antimicrobial activity of BCNs against spoilage organisms (SPOs) has raised considerable interest in their application in juice preservation. The objectives of the study were to: (i) isolate, identify and screen BCN producing bacteria for antimicrobial activity against spoilage bacteria and fungi, (ii) optimize production of BCN from selected producers and (iii) investigate the industrial application of the BCN as a preservative in fruit juice. Eleven LAB strains of BCN producers were screened for antimicrobial activity. BCNs from Lactobacillus plantarum and Pediococcus pentosaceus 34 were the most effective against juice spoilage bacteria and fungi. The effect of medium components on bacteriocin production in L. plantarum and P. pentosaceus 34 was also determined. Clementine:Valencia (1:1) juice was used for the first time as the growth medium for L. plantarum and P. pentosaceus 34. The BCN from L. plantarum showed the highest activity and was, therefore, chosen for juice fermentation studies. The identification of L. plantarum was confirmed by biochemical tests, polymerase chain reaction (PCR) and sequencing of the recA gene. The highest BCN activity was observed for L. plantarum grown in De Man-Rogosa-Sharpe (MRS) and a combination of all supplements (i.e. peptone, MnSO4.H2O, Tween 80, glucose and whey), followed by MRS and Tween 80, peptone, MnSO4.H2O and MRS alone. MRS was a better medium for BCN production than juice [Clementine:Valencia (1:1)]. Size exclusion chromatography (SEC) was used to isolate the active L. plantarum BCN fraction which corresponded to an approximate molecular weight of 3.2 kDa and was proteinaceous in nature. Plantaricin structural genes (plnEF, plnJ, plnK, plnN) were detected in the L. plantarum strain by PCR and sequenced, and were chromosomally encoded as no plasmids could be detected. This implies that the BCN from L. plantarum is most likely a type of class IIa plantaricin which is responsible for the broad inhibitory activity observed. For the industrial application studies, L. plantarum BCN-containing cell free supernatant (BCNsup) added to “Ready to Drink” (RTD) Clementine:Valencia (1:1) juice at concentrations of 3 600 - 500 000 ppm decreased growth of SPOs, Lactobacillus acidophilus and Streptococcus thermophilus. At 250 000 ppm, the L. plantarum BCNsup achieved 5.3 and 6.8 log reductions of the L. acidophilus, after 24 and 48 h, respectively, which is larger than the USFDA (2001) requirement of a 5 log reduction in SPO activity, for preservation of fruit juices. However, there was a decrease in the activity when the BCNsup was applied to industrial (Valor) RTD juice (mango-orange) at decreasing concentrations of 100 000, 50 000 and 25 000 ppm. Organoleptic tests showed that the BCN did not alter flavor or taste of the juice and did not cause toxicity or allergic reactions. A food safety risk assessment was conducted in order to determine the Critical Control Point(s) [CCP(s)] at which the BCN could be applied to control identified microbiological hazards, and a Hazard Analysis and Critical Control Point (HACCP) plan was developed. This is the first report on the optimisation of L. plantarum BCN production in juice [Clementine:Valencia (1:1)], followed by inoculation into RTD juice (mango-orange), including a HACCP plan for the application of the BCN as a preservative in juice.
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  • Date Issued: 2015

Application of Baylis-Hillman methodology in the synthesis of HIV-1 enzyme inhibitors

  • Authors: Manyeruke, Meloddy Hlatini
  • Date: 2015
  • Subjects: HIV infections , Enzyme inhibitors , AZT (Drug) , Bioconjugates
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4540 , http://hdl.handle.net/10962/d1017920
  • Description: The application of Baylis-Hillman methodology has afforded access to a range of β-hydroxypropionate ester-AZT conjugates as potential dual-action HIV-1 IN/RT inhibitors. Two families comprising a total of nine β-hydroxypropionate ester-AZT conjugates were synthesised. The first family was accessed using O-benzylated salicylaldehydes and methyl acrylate and the second from unprotected salicylaldehydes using tert-butyl acrylate as the activated alkene. Spectroscopic methods were employed to fully characterize the compounds. Propargylation of the respective Baylis-Hillman adducts was achieved via conjugate addition of propargylamine. The resulting products were then employed in Cu(I)-catalysed “click” reactions with azidothymidine (AZT) to yield the desired β-hydroxypropionate ester-AZT conjugates. Exploratory studies were also conducted to access 4-hydroxycoumarins from Baylis-Hillman derived adducts and to construct customized chiral Baylis-Hillman reaction sites. Many 4- hydroxycoumarins are known to exhibit a wide range of biological activities, and extending Baylis-Hillman methodology to access these systems is an important challenge. Two approaches were investigated. The first involved the formation of a 4-phthalimidocoumarin, aromatisation and hydrolysis of which was expected to lead to the 4-hydroxycoumarin target. The second, a variation of the first, involved the use of 4-(chrolomethyl)coumarin intermediates. Unfortunately, while various intermediates were prepared and characterised, neither approach led ultimately to the desired targets. N-substituted borneol-10-sulfonamides were constructed from camphor-10- sulfonyl chloride as chiral Baylis-Hillman reaction sites. In a preliminary study, however, none of the N-substituted borneol-10-sulfonamides exhibited Baylis-Hillman catalytic activity.
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  • Date Issued: 2015

Applications of social media and web 2.0 for research support in selected African academic institutions

  • Authors: Owusu-Ansah, Christopher M , Gontshi, Vuyokazi , Mutibwa, Lois , Ukwoma, Scholarstica
  • Date: 2015
  • Subjects: Social networks , Web 2.0. , Research -- Study and teaching
  • Language: English
  • Type: Article
  • Identifier: vital:6996 , http://hdl.handle.net/10962/d1018520
  • Description: This study examined the use of Social Media/Web 2.0 for research support and it is guided by three objectives namely: a) to ascertain the uses of social media in academic institutions; b) to identify the challenges associated with social media use for research purposes and c) to provide experiences of social media application in selected African academic institutions. The study makes use of literature analysis in combination with personal and professional work experiences on the use of social media from librarians in four different countries. Institutional experiences of the four librarians showed that it is only Rhodes University Library that uses social media in its library, which is as a result of a formal social media strategy. For the other three universities, University of Education, Winneba Library in Ghana, Makerere University Library in Uganda and the University of Nigeria Library, the use of social media is not encouraging. They use it mostly for communication and interaction with colleagues. It was also discovered that there is no social media strategy available in these university libraries. Based on these findings, the study recommended the implementation of a social media strategy, appointment of social media librarians in these libraries, and continuing professional development of librarians to keep abreast with current trends. Web 2.0/Social Media is a new technology offering new options for African academic librarians in their research support role
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  • Date Issued: 2015

Appraising the appraisal framework: evidence from Grahamstown property advertisements

  • Authors: Beangstrom, Tracy
  • Date: 2015
  • Language: English
  • Type: text , Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/54744 , vital:26608
  • Description: This thesis considers how interpersonal meaning choices in property advertisements are best reflected in a context of constraint in Grahamstown, South Africa, using and appraising Martin & White’s (2005) APPRAISAL Framework. The study is comparative in two senses since the data is analysed using Martin & White’s (2005) APPRAISAL Framework and a revision to it, and property advertisements from two competing estate agencies are analysed: Remax Frontier Properties and Pam Golding Properties. An initial strict application of Martin & White’s (2005) framework is followed by a second, based on analyst difficulties and framework limitations experienced in the first analysis, as well as those experienced by other researchers. Revisions to the original framework include added ‘local’, context-driven features and sub-categories: Exclusivity and Convenience in Attitude, a Scale of Intensity in Graduation, and a category ‘Invite’ in Engagement. These enable a richer, more detailed account of the alignment strategies and interpersonal micro-politics at play in the property advertisements than is possible using the original framework. Findings from the analyses reveal four facts of note. Firstly, that while the original Martin & White (2005) APPRAISAL Framework captures a general level of interpersonal meaning in the data, it does so more fully when it includes contextual and contextually-driven categories that are informed by local knowledge. Secondly, two levels of meaning are expressed in the data. One is aimed at an ‘external’ audience; the other, truer, fuller and more contentious, is aimed at what appears to be the intended audience only. Thirdly, and relatedly, specific contextual and cultural knowledge is needed by the intended audience to access the intended meaning. Fourthly, both estate agencies promote values of high prestige, exclusivity, elitism and wealth as their intended meaning to align a like-minded audience, although Remax Frontier Properties attribute these values to location and features of the home to a greater extent than Pam Golding Properties, who place greater emphasis on the size of the home. The thesis suggests further avenues for research into the discourse of property advertising, as well as into overcoming certain context-specific limitations of the APPRAISAL Framework.
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  • Date Issued: 2015

Approaches in the prioritisation of areas for biodiversity conservation: a case study from the Western Cape pf South Africa

  • Authors: Southey, Phillippa Kate
  • Date: 2015
  • Subjects: Biodiversity conservation -- South Africa -- Western Cape , Conservation of natural resources -- South Africa -- Western Cape
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10948/4122 , vital:20548
  • Description: Historical ad hoc allocations of land for biodiversity conservation have led to a biased representation of habitat within the Cape Floristic Region, with Protected Areas concentrated in upland areas at high altitudes and on steep slopes. The field of Conservation Planning developed to ensure that allocations of areas to Protected status no longer result in such bias and rather promotes the persistence of biodiversity. This study reviewed a recent allocation of land to biodiversity conservation within Western Cape of South Africa, using both a quantitative and qualitative approach, to determine their value to biodiversity conservation. The area was previously used for commercial forestry but now has been allocated to conservation land-uses. The allocation was based on the area’s value to the forestry industry. The qualitative approach in this study engaged with relevant stakeholder groups to map priority areas, while the quantitative approach used available data on biodiversity features to map priority areas. Neither approach determined that the area allocated is in its full extent a priority for biodiversity conservation. This indicated that in the current era of Conservation Planning, Protected Areas are still being allocated in an ad hoc manner, as a result of their limited perceived benefit to anthropocentric needs. The future allocation of land to biodiversity conservation should rather integrate expert knowledge and available quantifiable data to ensure that priority areas for biodiversity conservation are being protected.
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  • Date Issued: 2015

Aquatic invasions of the Nseleni River system: causes, consequences and control

  • Authors: Jones, Roy William
  • Date: 2015
  • Subjects: Gastropoda -- South Africa , Introduced snails -- South Africa , Introduced mollusks -- South Africa , Loricariidae , Introduced fishes -- South Africa , Water hyacinth , Alien plants -- South Africa
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:5928 , http://hdl.handle.net/10962/d1017806
  • Description: Globalization has seen an unprecedented dispersal of exotic and alien species worldwide resulting in worldwide homogenization and sometimes extinction of indigenous or endemic taxa. When an exotic species becomes established in a new habitat the invasive organisms are capable of having an impact on indigenous community dynamics and the overall structure and function of ecosystems. Furthermore, the impact of invasion is determined by the geographical range, abundance and the per-capita or per-biomass effect of the invader. However, the success of the introduced organisms is reliant on their ability to acclimate to the physiochemical conditions of the newly invaded environment.Freshwater ecosystems are especially vulnerable to invasions because there are numerous potential routes of introduction including intentional pathways such as stocking, and unintentional pathways such as the release of ballast water and aquarium releases. Efforts to limit the introduction of invasive species or to manage established exotic populations are often hindered by insufficient understanding of the natural history of problematic species. Relatively little is known regarding the physiological tolerances of many taxa. Knowledge about specific species ecophysiological constraints allows for the prediction of future patterns of invasion more accurately, including where an introduced organism would probably survive, thrive and disperse. Furthermore, data on the physiological tolerances of an introduced exotic organism may provide data necessary for effective management and control. This studyinvestigated three invasive species in the Nseleni River system in a protected area in KwaZulu-Natal. The species studied were, Tarebia granifera (Quilted melania – Lamarck, 1822), Pterygoplichthys disjunctivus (Suckermouth armoured catfish - Weber, 1991) and Eichhornia crassipes (water hyacinth – (Martius) Solms-Laubach,). The Nseleni River flows into Lake Nsezi which is responsible for providing potable water to the surrounding towns and industry, as well as the surrounding rural communities. The Enseleni Nature reserve has become the centre for biodiversity dispersal in the immediate area, due to the change in landscape surrounding the protected area.An important step in developing alien invasive species management strategies in protected areas is determining their extent and invasive traits. Tarebia granifera is a prosobranch gastropod originally from South-East Asia that has become invasive in several countries around the world including South Africa. Snail populations were sampled at nine sites throughout the Nseleni/Mposa river system every six weeks over a twelve month period. The snail was abundant throughout the system, especially in shallow waters of less than 1m in depth.The first positive identification the loricariid catfish Pterygoplichthys disjunctivus for the Nseleni River was in 2006. The original introduction is believed to have been via the aquarium trade. The aim of the study was to assess the usefulness of the unified framework with regard to management of fish invasions by assessing the invasion stage of the loricariid population and identifying appropriate management actions using the Blackburn et al. (2011) framework. The fish were sampled at nine different sites and three different depths over a period of twelve months, as well as when two ichthyological surveys were carried out on the Nseleni River system. This invasive fish has been located throughout the system and both male and female fish were collected. The smallest fish sampled was a fingerling of a day or two old and the smallest pregnant female was a mere 270mm TL. This is a clear indication that this fish is breeding in the river system.Although T. granifera and P. disjunctivus were abundant in the Nseleni/Mposa river system, it was not clear what their role in the system was, and in particular if they were competing with any of the indigenous species. Therefore, isotope samples were collected from numerous taxa over a two week period, with the exception of Pterygoplichthys disjunctivus samples, which were collected over 12 months. The δ13C and δ15N signatures of all samples were determined. The niche overlap between the invasive and indigenous snails was effectively zero (1.02E-13%), indicating no shared food resources. The medium ranges of dNRb (7.14) and dCRb (9.07) for the invasive fish indicate that it utilizes a wider range of food resources and trophic levels than the majority of indigenous fish. A medium CDb value (2.34) for the invasive fish species, P. disjunctivus, describes medium trophic diversity, with three indigenous species possessing higher diversity and three possessing lower diversity. Furtherresults indicated that there was no direct dietary competition between P. disjunctivus and indigenous species. Eichhornia crassipes was first recorded on the Nseleni River in 1978, and has been shown to have a significant negative impact on the biodiversity of the Nseleni/Mposa River system and therefore required a control intervention. Although biological control using the two weevil species Neochetina eichhornia (Warner) and N. bruchi (Hustache) has been credited with affecting a good level of control, the lack of a manipulated post-release evaluation experiments has undermined this statement. Five experimental plots of water hyacinth of 20m2 were sprayed with an insecticide to control weevils. After ten months the plants in the sprayed plots were significantly bigger and heavier than those in the control plots that had natural populations of the biological control agents. This study has shown unequivocally that biological control has contributed significantly to the control of water hyacinth on the Nseleni/Mposa River system.The management plan for the Enseleni Nature Reserve identifies the need to control invasive and/or exotic organisms within the boundary of the protected area. In addition, set guidelines have been implemented on how to control these organisms, so that indigenous organisms are least affected. Lack of control of exotic organisms can have serious consequences for indigenous species. It is therefore of utmost importance that the population dynamics of the invading organism be understood, what the potential impact could be and how to control them. Furthermore, it has also acknowledged the threat of possible exotic species invasions from outside of the protected area that might result in threats to the protected area and that these must be investigated, researched and managed.This thesis has identified Tarebia granifera, Pterygoplichthys disjunctivus and Eichhornia crassipes as being a threat to indigenous biodiversity within the protected area, as well as in adjacent areas to the protected area. The thesis will therefore investigate the hypothesis that both Tarebia granifera and Pterygoplichthys disjunctivus are having a direct negative effect on available food resources for indigenous species of organisms. In addition, this thesis will investigate if theNeochetina species that have previously been introduced onto E. crassipes are having any negative effect on this invasive alien aquatic plant.
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  • Date Issued: 2015

Art investment as a portfolio diversification strategy in South Africa

  • Authors: Botha, Ferdi , Scott, Brett , Snowball, Jeanette D
  • Date: 2015
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/67422 , vital:29086
  • Description: publisher version , Art has been suggested as a good way to diversify investment portfolios during times of financial uncertainty. The argument is that art exhibits different risk and return characteristics to conventional investments in other asset classes. The new Citadel Art Price index offered the opportunity to test this theory in the South African context. The Citadel index uses the hedonic regression method with observations drawn from the top 100, 50 and 20 artists by sales volume, giving approximately 29 503 total auction observations. The Index consists of quarterly data from the period 2000Q1 to 2013Q3. A VAR of the art price index, Johannesburg Stock Exchange all-share index, house price index, and South African government bond index were used. Flowing from the VAR results, additional analyses included variance decomposition, impulse response, and, to determine volatility, variance and standard deviation measures for each index. Results show that, when there are increased returns on the stock market in the previous period and wealth increases, there is a change in the Citadel Art Price Index in the same direction. This finding is consistent with Goetzmann et al. (2009), who reported that there is a strong relationship between art and equity markets and that art price changes are driven by capital gains and losses. No significant difference was found between the house price index and the art price index, and neither between the art and government bond price indices. Overall, the South African art market does not offer the opportunity to diversify portfolios dominated by either property, bonds, or shares.
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  • Date Issued: 2015

Articulating the nature of clinical nurse specialist practice

  • Authors: Bell, Janet Deanne
  • Date: 2015
  • Subjects: Nurse practitioners , Intensive care nursing
  • Language: English
  • Type: Thesis , Doctoral , DPhil
  • Identifier: vital:10057 , http://hdl.handle.net/10948/d1018623
  • Description: Critical care nursing is a clinical specialist nursing practice discipline. The critical care nurse provides a constant presence in the care of a critically ill patient. She/he creates a thread of continuity in care through the myriad of other health care professionals and activities that form part of a patient’s stay in the critical care environment (World Federation of Critical Care Nurses [WFCCN], 2007). During conversations with people who have had intimate experience of the critical care environment, they have offered anecdotes that describe their interaction with critical care nurses who they perceive to be different from and better than other critical care nurses they encountered. Despite having met common professional requirements to be registered as a clinical specialist nurse, these distinctive, unique abilities that seem to be influential in meeting the complex needs and expectations of critically ill patients, their significant others as well as nursing and medical colleagues, are not displayed by all critical care nurses. While students of accredited postgraduate nursing programmes are required to advance their nursing knowledge and skill competence, many students do not seem to develop other, perhaps more tacit, qualities that utilisers characterise in their anecdotes of ‘different and better’ nursing practice. The overarching research question guiding this study was how can ‘different and better’ critical care nursing practice as recognised by a utiliser be explained? The purpose of this study was to develop an understanding of the qualities that those people who use critical care nursing practice recognise as ‘different and better’ to the norm of nursing practice they encounter in this discipline. The participant sample included patients’ significant others, nursing colleagues and medical colleagues of critical care nurses, collectively identified as utilisers. The stated aim of this work was to construct a grounded theory to elucidate an understanding of the qualities that a utiliser of critical care nursing recognises as ‘different and better’ critical care nursing practice in order to enhance the teaching and learning encounters between nurse educators and postgraduate students in learning programmes aiming to develop clinical specialist nurses. The method processes of grounded theory are designed to reveal and confirm concepts from within the data as well as the connections between these concepts, supporting the researcher in crafting a substantive theory that is definitively grounded in the participants’ views and stories (Streubert & Carpenter, 2011: 123, 128-129). Two data collection tools were employed in this study, namely in-depth unstructured individual interviews and naïve sketch. Constant comparative analysis, memo-writing, theoretical sampling, theoretical sensitivity and theoretical saturation as fundamental methods of data generation in grounded theory were applied. The study unfolded through three broad parts, namely: Forming & shaping this grounded theory through exploration and co-creation; Assimilating & situating this grounded theory through understanding and enfolding; Reflecting on this grounded theory through contemplating and reconnecting. The outcome of the first part of the study was my initial proposition of a grounded theory co-created in the interactions between the participants and myself. This was then challenged, developed and assimilated through a focussed literature review through the second part of the study. Through these two parts of this study, an inductively derived explanation was formed and shaped to produce an assimilated and situated substantive grounded theory named Being at Ease. This grounded theory articulates how ‘better and different’ nursing is recognised from the point of view of those who use the nursing ability of critical care nurses through the core concern ‘being at ease’ and its four categories ‘knowing self’, ‘skilled being’, connecting with intention’ and’ anchoring’. The final part of this study unfolded in my reflections on what this grounded theory had revealed about nurses and elements of nursing practice that are important to a utiliser in recognising ‘different and better’ critical care nursing. I suggest that as nurses we need to develop a language that enables us to reveal with clarity these intangible and tacit elements recognised within the being and doing of ‘different and better’ nursing. I reflected on the pivotal space of influence a teacher has with a student, and on how the elements essential in being and doing ‘different and better’ nursing need to be evident in her/his own ways of being a teacher of nursing. Teaching and learning encounters may be enhanced through drawing what this theory has shown as necessary elements that shape ‘different and better’ nurses through the moments of influence a teacher has in each encounter with a student.
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  • Date Issued: 2015

Aspects of the biology and life history of largespot pompano, Trachinotus botla, in South Africa

  • Authors: Parker, Daniel M , Booth, Anthony J
  • Date: 2015
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/123798 , vital:35499 , https://doi.10.1071/MF14029
  • Description: Trachinotus botla is an important recreational surf zone-dependent fish species distributed in the Indo-west Pacific from South Africa to Australia. In South Africa it is restricted to the northern KwaZulu-Natal coast. Biological investigations revealed that it is a fast growing species that attains a maximum age of, 7 years. Males and females sexually matured in their third year. It has a protracted summer spawning season with evidence of serial spawning behaviour. T. botla is an opportunistic predator with a generalist diet, with fish feeding on a wide variety of prey items particularly those that are temporally ‘superabundant’. Small fish fed predominantly on copepods and terrestrial insects, whereas larger fish consumed bivalves and crabs. Teleosts, primarily engraulids, were important components to the diet of fish of all sizes. An ontogenetic dietary shift was observed just after sexual maturity (300-mm fork length) that is possibly linked to a change in habitat preference with larger fish foraging on deeper reefs.
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  • Date Issued: 2015

Aspects of the biology, thermal physiology and nutritional ecology of Pareuchaetes insulata (Walker) (Lepidoptera: Erebidae: Arctiinae), a specialist herbivore introduced into South Africa for the biological control of Chromolaena odorata (L.) King and Robinson (Asteraceae)

  • Authors: Uyi, Osariyekemwen
  • Date: 2015
  • Subjects: Chromolaena odorata , Chromolaena odorata -- Biological control -- South Africa , Arctiidae
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:5936 , http://hdl.handle.net/10962/d1017916
  • Description: Chromolaena odorata (L.) King and Robinson (Asteraceae) is an invasive weedy shrub native to the Americas that has proven to be a significant economic and ecological burden to many tropical and sub-tropical regions of the world where it impacts negatively on agriculture, biodiversity and livelihoods. A distinct biotype of C. odorata was first recognised as naturalized in KwaZulu-Natal (KZN) province, South Africa, in the 1940s and has since spread to other climatically suitable provinces. Pareuchaetes insulata (Walker) (Lepidoptera: Erebidae: Arctiinae) was released in KZN, South Africa, as a biological control agent against the weed between 2001 and 2009. Although the moth did establish at one out of some 30 release sites, its population level is generally low in the field. This thesis attempts to unravel the reasons for the poor performance of P. insulata in South Africa.Studies of life history traits of P. insulata in the laboratory indicated that the moth possess good biological attributes such as low mortality, high fecundity, egg hatchability and high female mating success. Overall, adult female moths eclosed before their male counterparts suggesting the presence of protogyny. Beyond the contribution of this study to our understanding of the life history traits of erebid moths, it hypothesized that the absence of protandry might have contributed to the low population levels of the moth in the field. To determine if a degree of agent-host plant incompatibility is culpable for the poor performance of P. insulata, insect performance metrics were compared on two distinct C. odorata plants (one from Florida and another from South Africa) in laboratory experiments. Pareuchaetes insulata performance metrics were similar on both plant forms; there were no significant differences in total leaf area consumed, egg and larval development, immature survival rates, feeding index (FI), host suitability index (HSI), growth index (GI), and fecundity between the Floridian and southern African C. odorata plants. In sum, there was no evidence to demonstrate that differences in plant forms in C. odorata are culpable for the poor performance of P. insulata in South Africa.The effects of temperature on the developmental and reproductive life history traits, locomotion performance and thermal tolerance range of P. insulata were studied in order to elucidate the possible role of temperature on the poor performance of the moth. The results showed that at temperatures below 25 °C, mortality increased and development time was prolonged. Fecundity and egg hatchability were negatively affected at a constant temperature of 15 °C. Results futher showed that third instar larvae were unable to initiate movement at 6 °C and locomotor abilities were significantly reduced at 11 °C. In sum, it is hypothesized that both direct and indirect negative impacts of low temperature may partly explain the poor performance of P. insulata in South Africa. Theeffects of seasonal and spatial variations in the leaf characteristics of C. odorata on the performance of P. insulata were investigated. Foliar nitrogen and magnesium concentrations were higher in shaded plants during winter due to low temperatures. Leaves of C. odorata plants growing in the shaded habitat (relative to full sun) and leaves of plants during autumn (relative to winter) were more nutritionally balanced and suitable for herbivore performance. Consequently, P. insulata developed faster, had heavier pupal mass and increased fecundity when reared on shaded leaves (relative to full sun) or when reared on autumn leaves compared to leaves growing in winter. This study demonstrates that low winter temperatures can indirectly affect insect herbivore performance by changing the phytochemistry of host plant and hypothesized that excess nitrogen and possibly magnesium may have detrimental effects on the insect herbivore performance.A cross-feeding experiment was conducted to determine P. insulata response to a change in the diet of offspring due to a shift in plant quality in shaded versus full sun habitats. The results showed that a ‘negative switch’ in herbivore diet (i.e. when progeny from parents reared on shaded leaves were fed on full sun leaves) resulted in high (40%) mortality, prolonged development time and reduced fecundity. Thus full sun foliage is an inferior diet for P. insulata offspring. In laboratory experiments, foliar nitrogen was positively correlated with the performance of P. insulata. From this study, it is demonstrably evident that the poor performance of P. insulata on C. odorata in South Africa is caused by multiple factors such as low temperatures as well as spatio-temporal variations in the leaf characteristic of C. odorata leaves. This study shows the complexity of determining the causes of low populations and apparent low impact of biological control agents and herbivorous insects generally, in the field. The implications of this research to the biological control programme against C. odorata and the direction of future research for the control of C. odorata are discussed.
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  • Date Issued: 2015

Assessing ecological intelligence and behaviours in organisations

  • Authors: Hill, Hayden Clee
  • Date: 2015
  • Subjects: Sustainable development -- Management , Social responsibility of business , Executive ability
  • Language: English
  • Type: Thesis , Masters , MBA
  • Identifier: http://hdl.handle.net/10948/8284 , vital:26319
  • Description: The earth has been undergoing a process of global warming and climate change for a period exceeding 100 years. These two occurrences have had many adverse effects on the sustainability of the environment as well as on humans and organisations. The direct cause of global warming and climate change, including the consequential negative ramifications, are due to humans use of natural resources mostly in the form of the consumption of products and services. Organisations are regarded as the largest consumers of products and services within society and as a result are responsible for the major contributions made to global warming and climate change. In order to rectify the negative impact made by organisations in terms of their ecological behaviour and ensure organisational sustainability theory, stipulates that a behavioural change within leadership is required. Ecologically intelligent leaders who hold an affirmation of an ecological worldview and enact pro-ecological behaviours are pivotal to the proliferation of ecological leadership and a subsequent rise in organisational pro-ecological behaviour, towards a sustainable future. On the basis of the above mentioned statements, gained from various literature, a conceptual model was formed and an exploratory research study undertaken to substantiate the presence of correlational or causal relationships between a leader’s ecological intelligence with the enactment of ecological leadership and organisational pro-ecological behaviour. The sample consisted of 42 respondents who occupied positions of leadership within organisations that were members of the Southern African Association for Energy Efficiency. The findings provide substantiating evidence of the presence of ecological intelligence within leadership, the enactment of ecological leadership as well as organisational pro-ecological behaviour. Furthermore significant correlational relationships exist between ecological leadership and organisational pro-ecological behaviour. There is also substantiating indication that the enablers of a leader’s ecological intelligence, an affirmation of an ecological worldview and pro-ecological behaviour, facilitate the outcome of organisational pro-ecological behaviour.
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  • Date Issued: 2015

Assessing law enforcement's ability to fight cybercrime in South Africa

  • Authors: Moleko, Tsepo
  • Date: 2015
  • Subjects: Computer crimes -- South Africa Law enforcement -- South Africa
  • Language: English
  • Type: Thesis , Masters , MBA
  • Identifier: http://hdl.handle.net/10948/11470 , vital:26929
  • Description: Cybercrime is the use of technology to support or directly facilitate a criminal activity, with logon credentials being the main information asset targeted during a cybercrime. The one time passwords used by banks to protect their clients from cybercrime are also under attack by cybercriminals. The Internet has made it easy to commit cybercrime, with perpetrators experiencing virtually no risk with huge returns. Individual cybercrime cases are sometimes small in nature, which means that the police can be reluctant to commit the resources necessary to investigate every incident. There is a distinct lack of resources, skills, knowledge and training in relation to identifying, understanding and responding to the growing threat of cybercrime. This research addresses how to solve these issues in South Africa in order for cybercrime to be tackled effectively and for perpetrators to be prosecuted.
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  • Date Issued: 2015

Assessing public administration implications of the use and disposal of agro-chemicals in A2 farms in Zimbabwe : a case study of Chirumhanzu District

  • Authors: Matunhu, Viola
  • Date: 2015
  • Subjects: Agricultural chemicals , Hazardous waste treatment facilities , Pesticide waste
  • Language: English
  • Type: Doctoral theses , text
  • Identifier: http://hdl.handle.net/10353/26481 , vital:65471
  • Description: This study is concerned with use and disposal of agro-chemical in A2 farms in Zimbabwe with specific reference to Chirumhanzu District. The study is located in the field of public administration. A transformational mixed research design was employed in the collection, analysis and interpretation of the field data. The study involved farm employees in 21 A2 farms that use agro-chemicals to enhance farm productivity. Non probability sampling techniques were employed to select the participating farms. Interviews, questionnaires, literature search, and observation where the main data collection instruments. A total of 150 purposively selected employees drawn from 21 participating farms participated in the study. The findings of this empirical study, which uses the terms I, the researcher, and the study interchangeably, were that there is poor use and management of agro-chemicals in the area. Most farm employees do not adhere to instructions on use and disposal of the chemicals and there is a weak monitoring and evaluation of the use and disposal of agro-chemicals on the farms. Yet, most of these chemicals are carcinogens. Farm employees need to be trained on personal and public health implications of poor management of agro-chemicals. Labels on containers that store chemicals need to be written in both English and vernacular, which is not the case in the district. Labels on most of the chemicals on the farms studied are written in English and technical terms are used. Although, most of the employees on the farms are literate, they find it difficult to understand the jargon on labels. , Thesis (PhD) -- Faculty of Management and Commerce, 2015
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  • Date Issued: 2015

Assessing symptoms of eutrophication in estuaries

  • Authors: Lemley, Daniel Alan
  • Date: 2015
  • Subjects: Estuarine eutrophication -- South Africa , Water quality -- South Africa , Ecological integrity -- South Africa
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10948/3427 , vital:20429
  • Description: Water quality and ecological integrity of estuaries reflect activities within the entire upstream catchment. Much emphasis has been placed on the response of estuaries to anthropogenic stressors through the use of monitoring programmes. Key to the success of these programmes is the use of indicators as they transform data into useful information. The ultimate aim of this study was to identify eutrophic symptoms in selected estuaries in the Gouritz Water Management Area (WMA) using a multi-metric classification method. The study sites included the permanently open Duiwenhoks, Goukou, Gouritz, and Kaaimans estuaries, as well as the temporarily open/closed Hartenbos, Klein Brak, Great Brak, Gwaing, and Goukamma estuaries. Initially, the “pressure” associated with all the estuaries in the Gouritz WMA was determined (e.g. total daily nutrient loads and changes in river inflow affecting flushing time) using long-term flow and water quality monitoring data provided by the Department of Water Affairs (DWA). Subsequently, the “state” of the selected estuaries was assessed using a variety of indicators, including: inorganic nutrients (~ N and P), phytoplankton, epiphytes and microphytobenthos. Estuaries with longer flushing time suggested greater vulnerability to eutrophication. For example, the Gwaing (281.11 kg DIN d-1; 78.85 kg DIP d-1) and Hartenbos (38.33 kg DIN d-1; 21.51 kg DIP d-1) estuaries generally received the highest daily inorganic nutrient loads. However, at the time of sampling, the Hartenbos Estuary had a longer flushing time (i.e. weeks) compared to the Gwaing Estuary (i.e. couple of days). Field data confirmed the greater vulnerability to eutrophication associated with longer flushing times, as the indicators measured in the Hartenbos Estuary exceeded all the proposed ‘thresholds’ of a eutrophic system (~ overall ‘Poor’ condition). The Great Brak Estuary (~ overall ‘Fair’ condition) provided an interesting example where eutrophic symptoms were only detected when assessing the microalgal primary producers (i.e. high biomass and low diversity). Furthermore, the need to distinguish between naturally and anthropogenically induced symptoms was highlighted. One such scenario was noted in the Kaaimans Estuary, where its natural hydro-morphological characteristics (i.e. steep banks, low river inflow, and deep/narrow channel) led to the possible exaggeration of its overall eutrophic condition, i.e. received a ‘Fair’ rather than ‘Good’ rating, arising from ‘Poor’ ratings for dissolved oxygen and benthic diatom diversity. Overall, this study demonstrated the importance of adopting a holistic approach when assessing the condition and trophic status of estuaries. Studies such as these allow for the detection of vulnerable and degraded systems, which can provide important information with regards to the identification of management priorities.
  • Full Text:
  • Date Issued: 2015
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