Synthesis and biological evaluation of anti-HIV-I integrase agents
- Authors: Jesumoroti, Omobolanle Janet
- Date: 2017
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/59215 , vital:27479
- Description: Expected release date-April 2019
- Full Text:
- Date Issued: 2017
Synthesis and evaluation of arylpyrrole-chalcone hybrids as antiplasmodial and antitrypanosomal agents
- Authors: Zulu, Ayanda Ignatia
- Date: 2017
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/65268 , vital:28716
- Description: Expected release date-May 2019
- Full Text:
- Date Issued: 2017
Synthesis and photophysical studies of crown ether-bodipy dyes and the fabrication of bodipy embedded fluorescent nanofibers
- Authors: Stone, Justin
- Date: 2017
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/4953 , vital:20746
- Description: This study has three major objectives: 1) to synthesize a series of structurally related BODIPY dyes, 2) to fabricate BODIPY embedded electrospun nanofibers, and 3) to investigate and characterize the photophysical properties of all synthesized BODIPY dyes with a special focus on their ability to generate singlet oxygen. This thesis first explores the acid catalysed condensation reaction to produce two structurally analogous meso-substituted BODIPY dyes based on cuminaldehyde and 4-dimethylaminobenzaldehdye. In order to enhance the rate of ISC and promote the generation of reactive oxygen species bromine atoms were then attached to the BODIPY 2,6-positions. These BODIPY dyes were then embedded in a polystyrene solution and electrospun into nanofibers. The resulting nanofibers were found to be highly fluorescent, but were no longer able to generate singlet oxygen. Ion-sensitive BODIPYs were prepared from the dibrominated BODIPY dyes by employing a modified Knoevenagel condensation reaction to form a styryl bond with 4’-formylbenzo-15-crown-5 at the 3,5-position of the BODIPY core. Changes in the morphology and position of the absorption and emission spectra of these crown ether-styryl BODIPY dyes were observed in the presence of sodium ions. These results imply that crown ether-substituted BODIPY dyes could function as ion sensors.
- Full Text:
- Date Issued: 2017
Synthesis and physicochemical evaluation of a series of boron dipyrromethene dye derivatives for potential utility in antimicrobial photodynamic therapy and nonlinear optics
- Authors: Kubheka, Gugu Patience
- Date: 2017
- Subjects: Dyes and dyeing -- Chemistry , Photochemotherapy , Cancer -- Photochemotherapy , Anti-infective agents , Nonlinear optics , BODIPY
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/4776 , vital:20723
- Description: A series of new BODIPY dye derivatives have been synthesized and characterized using various characterization tools such as 1H-NMR, MALDI-TOF mass spectrometry, FT-IR, UV-visible spectrophotometry and elemental analysis. The aniline-substituted BODIPY derivative was further coordinated with gold nanorods and the characterization was achieved by transmission electron microscopy (TEM), X-ray diffractometry (XRD) and X-ray photoelectron spectroscopy (XPS).In addition to this dye, quaternized BODIPY dyes were also synthesized and investigated for their potential utility as photosentitizers in antimicrobial photodynamic therapy (APDT).BODIPY dyes with pyrene substituted styryl groups were embedded in polymer thin film using poly(bisphenol A carbonate) (PBC) to study their optical limiting properties. The optical limiting values of these BODIPY dyes once embedded in thin films were found to be greatly improved and the limiting intensityof each film was well below the maximum threshold which is set to be 0.95 J.cm-². The physicochemical properties and NLO parameters of all of the synthesized dyes were investigated.
- Full Text:
- Date Issued: 2017
Synthesis of indium and lead phthalocyanine as photocatalysts for photodynamic antimicrobial chemotherapy and photo-oxidation of pollutants
- Authors: Oluwole, Oluyinka David
- Date: 2017
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/5293 , vital:20805
- Full Text:
- Date Issued: 2017
Synthesis of indium and lead phthalocyanine as photocatalysts for photodynamic antimicrobial chemotherapy and photo-oxidation of pollutants
- Authors: Osifeko, Olawale L
- Date: 2017
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/5221 , vital:20790
- Description: This thesis explores the synthesis of metallophthalocyanines as potential photosensitizers for application in photodynamic antimicrobial chemotherapy and phototransformation of environmental pollutants. The metallophthalocyanines containing amino substituent were conjugated with magnetic nanoparticle and semiconductor quantum dots via an amide bond and by chemisorption onto gold nanoparticles surface. Techniques such as time-resolved fluorescence measurements, transmission electron microscopy, X-ray photoelectron spectroscopy (XPS), elemental analysis, fourier transform infrared (FTIR), nuclear magnetic resonance (¹H, ¹³C, and cozy of symmetrical phthalocyanine), electronic spectroscopy, as well as mass spectroscopy were employed to characterize all metallophthalocyanines. Quarternized pyridyloxy substituted phthalocyanine and asymmetric (AB3) metallophthalocyanines were embedded in electrospun polystyrene fiber. General trends are described for quantum yields of fluorescence, triplet, singlet oxygen and photodegradation as well as lifetimes of fluorescence and triplet state of the compounds. There is an increase in triplet quantum yield for Pcs in the presence of gold nanoparticles (AuNPs) and semiconductor quantum dots (QDs), but not in the presence of magnetic nanoparticles (MNPs). Photodynamic inactivation of Escherichia coli with the quarternized photosensitizers at low concentrations totally inactivate the bacteria compared to non-charged photosensitiser. Also, a similar trend was observed for the magnetic nanoparticles conjugates. Photooxidations of bisphenol A and 4-chlorophenol were carried out in this study using two asymmetric Indium(III) phthalocyanines photosensitizers. The photooxidation reactions were compared with those of a symmetrical indium(III) phthalocyanines containing four quaternized 4-pyridyloxy substituents. The complexes were embedded in electrospun polystyrene fiber for heterogeneous photocatalysis. The immobilized photosensitizers possess good singlet oxygen generation potentials in aqueous media. The asymmetrical phthalocyanine containing 4-pyridylsulfanyl and one aminophenoxy showed the best photocatalytic behavior.
- Full Text:
- Date Issued: 2017
Synthesis, characterisation and evaluation of novel ferrocene-thiazole derivatives as antiplasmodial agents
- Authors: Hakizimana, Emmanuel Victor
- Date: 2017
- Subjects: Plasmodium , Malaria -- Chemotherapy , Plasmodium falciparum , Plasmodium -- Inhibitors , Drug resistance in microorganisms , Thiaszoles
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/5304 , vital:20807
- Description: Malaria is mosquito-transmitted disease which continues to pose threat to humanity, despite the efforts undertaken by the scientific community, government entities and international organizations. The major problem is that Plasmodium species have developed resistance against available drugs. In order to counter this problem, antimalarial drugs that are efficacious and with novel mode of action are of great necessity. Thiazole derivatives, in particular aminomethylthiazole analogues, have been shown to exhibit promising antimalarial activity against Plasmodium falciparum strains. Previous studies reported the hit compound MMV010539, which showed good antimalarial activity against both K1 (CQ and multidrug resistant strains) and NF54 (CQ sensitive strain). In this study, MMV010539 was deemed to be as an attractive compound to generate novel analogues by addition of ferrocenyl organometallic unit. The ferrocene based compounds have shown biological activity; and with ferroquine currently in clinical trials there has been increasing research into identifying new ferrocenyl-containing molecules as potential antimalarial agents. Herein, thiazole ferrocene based molecules 3.22a-e were synthesised in low to good yields. Their structural identities were confirmed using conventional spectroscopic techniques (¹H and ¹³C NMR, FT-IR spectroscopy and mass spectrometry). The cell cytotoxicity assay of all final compounds confirmed that all ferrocene-thiazole blends 3.22a-e were non-toxic against HeLa cell lines. However, the in vitro biological assay revealed that despite the absence of cell cytotoxicity these compounds poorly inhibited the growth of Plasmodium falciparum parasite. As the aim was to expand further the structure-activity relationship (SAR) of MMV010539, this study confirmed the previous findings that there is a limited structural modification that could be accommodated as indicated in Figure 3.3 (Panel C). Moreover, the combination of ferrocenyl moiety and various alkylamines resulted in compounds with poor antiplasmodial potency, further suggesting that the free amine (Panel A, Figure 3.3) is important for activity.
- Full Text:
- Date Issued: 2017
Synthesis, characterisation and evaluation of novel ferrocene-thiazole derivatives as antiplasmodial agents
- Authors: Hakizimana, Emmanuel Victor
- Date: 2017
- Subjects: Plasmodium , Malaria -- Chemotherapy , Plasmodium falciparum , Plasmodium -- Inhibitors , Drug resistance in microorganisms , Thiaszoles
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/96068 , vital:31232
- Description: Malaria is mosquito-transmitted disease which continues to pose threat to humanity, despite the efforts undertaken by the scientific community, government entities and international organizations. The major problem is that Plasmodium species have developed resistance against available drugs. In order to counter this problem, antimalarial drugs that are efficacious and with novel mode of action are of great necessity. Thiazole derivatives, in particular aminomethylthiazole analogues, have been shown to exhibit promising antimalarial activity against Plasmodium falciparum strains. Previous studies reported the hit compound MMV010539, which showed good antimalarial activity against both K1 (CQ and multidrug resistant strains) and NF54 (CQ sensitive strain). In this study, MMV010539 was deemed to be as an attractive compound to generate novel analogues by addition of ferrocenyl organometallic unit. The ferrocene based compounds have shown biological activity; and with ferroquine currently in clinical trials there has been increasing research into identifying new ferrocenyl-containing molecules as potential antimalarial agents. Herein, thiazole ferrocene based molecules 3.22a-e were synthesised in low to good yields. Their structural identities were confirmed using conventional spectroscopic techniques (¹H and ¹³C NMR, FT-IR spectroscopy and mass spectrometry). The cell cytotoxicity assay of all final compounds confirmed that all ferrocene-thiazole blends 3.22a-e were non-toxic against HeLa cell lines. However, the in vitro biological assay revealed that despite the absence of cell cytotoxicity these compounds poorly inhibited the growth of Plasmodium falciparum parasite. As the aim was to expand further the structure-activity relationship (SAR) of MMV010539, this study confirmed the previous findings that there is a limited structural modification that could be accommodated as indicated in Figure 3.3 (Panel C). Moreover, the combination of ferrocenyl moiety and various alkylamines resulted in compounds with poor antiplasmodial potency, further suggesting that the free amine (Panel A, Figure 3.3) is important for activity.
- Full Text:
- Date Issued: 2017
Systematics and biogeography of forest snails, chondrocyclus (mollusca: gastropoda: caenogastropoda: cyclophoridae) in Southern Africa
- Authors: Cole, Mary Louise
- Date: 2017
- Subjects: Chondrocyclus , Mollusks -- South Africa , Cyclophoridae -- South Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/4356 , vital:20651
- Description: This study presents a molecular phylogeny and systematic revision of Chondrocyclus, the major South African group of the large family of operculate terrestrial molluscs, the Cyclophoridae. Chondrocyclus snails are small gastropods found in forest and moist thicket throughout South Africa. This is the first detailed systematic treatment of a group of Cyclophoridae in mainland Africa and the first to provide molecular data. This study complements regional studies on the systematics of the family in Asia and provides comparative data for studies of higher level relationships within the Cyclophoridae. Phylogenetic reconstruction by BI and ML methods of combined and single gene datasets of 16S and CO 1 all showed Chondrocyclus to be monophyletic and recovered five well-supported clades that corresponded to groups of populations identifiable on the basis of combinations of morphological characters. Species were diagnosed morphologically and were shown to be genetically distinct lineages. Informative morphological features include shell dimensions, protoconch, periostracum, operculum, radula and penis. Two species in Afromontane regions of Zimbabwe and Malawi respectively are excluded from Chondrocyclus based on morphology and tentatively placed in Cyathopoma. Diversity recognised within the genus more than doubled, from a previous seven South African species to seventeen. Re-descriptions of established species and descriptions of new species are provided, together with photographs of morphological characteristics. New taxon names and nomenclatural acts within it are disclaimed and are therefore not available in the sense of the International Code of Zoological Nomenclature until validly published elsewhere. Several cryptic species within previously widespread “species” and unrecorded narrowly endemic species were documented. The clade consisting of populations of “Chondrocyclus isipingoensis”, now considered to be a species complex, was sister to a group containing the other four clades. The “Isipingoensis” clade occurs widely in Afromontane regions, along the Great Escarpment, and on the south-east coast. The other four clades occur from Zululand to the Cape Peninsula with a pattern of east-west lineage turnover. The biogeography of Chondrocyclus is interpreted by comparison with concordant patterns in other terrestrial molluscs and unrelated taxa with poor dispersal ability. This study complements other research on composition, spatial distribution and phylogenetic diversity of low-vagility invertebrates and expands the data available for biodiversity conservation in South Africa.
- Full Text:
- Date Issued: 2017
Talent management: a case study of Namibia’s Directorate of Civil Aviation (DCA) in securing talent for aviation safety, 2008 to 2014
- Authors: Simataa, George
- Date: 2017
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/7131 , vital:21220
- Description: This study is about talent management, focusing on a case study of the initiatives undertaken by the Directorate of Civil Aviation (DCA) of Namibia over the period 2008 to 2014 in securing talent for aviation safety. The International Civil Aviation Organisation (ICAO) regularly assesses the extent to which member states comply with their safety oversight responsibilities. According to a 1996 report by the ICAO, under the auspices of its Universal Safety Oversight and Security Audit Programme (USOSAP), Namibia’s safety oversight was found to be weak, as indicative of the State’s inability to guarantee the safety of aircraft operations within the national airspace (ICAO, 1996). One of the significant audit findings was the critical shortage of qualified professionals at the Directorate Civil Aviation (DCA) to effectively perform the State’s regulatory and oversight function as contained in the Chicago Convention of 1944. The shortage of qualified professionals resulted in Namibia being unable to respond to its obligations and responsibilities under the Chicago Convention and Namibia’s subsequent blacklisting by the ICAO Audit Result Review Board (ARRB). Consequently, a corrective action plan was undertaken. This study examines one aspect of this plan, namely the initiatives that were undertaken to secure the talent required for aviation safety posts. The aim of the research is, from the perspective of talent management, to analyse the corrective action plan of the Directorate of Civil Aviation (DCA), as a process of securing talent for strategic positions in aviation safety in Namibia. This initiative was analysed from the perspective of the fourth stream of talent management, which emphasises securing talent for strategic positions (Collings and Mellahi, 2009; Huselid & Becker, 2011). Taking into account the fact that Namibia was a racially and culturally divided society until about 25 years ago, the study also deals with issues of diversity management as they impacted upon the talent management of the civil aviation industry nationally. Furthermore, the study is located against the background of the Bantu Education System that was provided by the apartheid South African government to Namibians before independence in 1990. The research design of this study involved conducting a case study that followed a deductive approach. Data were collected using multiple methods and sources such as documentation, interviews and archival records. Content analysis was used in the analysis of collected data. The findings of the study showed the talent management strategies that were adopted in managing strategic positions, the challenges encountered and the impact of the programme. The findings were initially discussed from the perspective of stream four of talent management, with its focus on strategic positions in organisations. Some of the findings of the study were in line with this approach to talent management, but certain challenges that were encountered in carrying out the talent management programme could not be addressed from this perspective, thereby exposing the limits of this approach to talent management in an emerging economy like Namibia. Consequently, a proposed model of sustainable talent management for the DCA was developed. From the perspective of this model of sustainable talent management, recommendations were made for practice and further research.
- Full Text:
- Date Issued: 2017
Taste masking of clarithromycin with ion exchange resins
- Authors: Ntemi, Pascal Vitalis
- Date: 2017
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/65178 , vital:28701
- Description: Expected release date-May 2019
- Full Text:
- Date Issued: 2017
Teachers’ use of situated learning approaches to teach environmental topics in Natural Science and Health Education: a multi-case study of two Namibian teachers
- Authors: Mamili, Joy Z
- Date: 2017
- Subjects: Environmental education -- Namibia , Science -- Study and teaching -- Namibia -- Cast studies , Health education -- Namibia -- Case studies
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/40901 , vital:25037
- Description: This study focuses on the use of situated learning approaches in the teaching of environmental topics in Natural Science and Health Education (NSHED) and is the first of its kind in Namibia. Although situated learning approaches, as examples of learner-centred pedagogy, are advocated in national education policies, little empirical research has been conducted in Namibia into how situated learning approaches play out in classroom practice. Therefore, the goal of this study was to find out how NSHED teachers use situated learning approaches when teaching environmental topics. The study reviews the characteristics of situated learning theory and clarifies situated learning approaches as a form of learner-centred pedagogy which is actively promoted in the Namibian schooling system. The study commences with a contextual profile of the communities around the two selected schools. This describes the socio-economic and social-ecological context in which learners are taught about environmental topics. The profile also describes the under-performance of the schools in recent national assessments, especially in relation to environmental topics in NSHED. Drawing on data generated through document analysis, semi-structured interviews and classroom observations, the study concluded that: 1. NSHED teachers both knew about and wished to create an authentic context to enhance situated learning approaches. However, their understandings and applications of situated learning tended to be basic. 2. Teachers dominated the scaffolding process and their scaffolding strategies did not enable learners to increase independence in performing. 3. Despite the use of situated learning approaches, learners’ engagement with lesson content was superficial, and the teachers did little to encourage deeper reflections or critical thinking. 4. The teachers appeared to use situated learning approaches to clarify subject content but not to encourage broader environmental understanding, action-taking and change. Based on the research findings, the study recommends that situated learning approaches be integrated into pre- and in-service teacher training with the aim of enhancing teachers’ understanding regarding the use of situated learning approaches in the teaching of environmental topics in NSHED.
- Full Text:
- Date Issued: 2017
The clinical utility of the Kinetic School Drawing (KSD)
- Authors: Mohammed, Raghshanda
- Date: 2017
- Subjects: Kinetic Family Drawing Test , Art therapy for children , Kinetic-House-Tree-Person Technique , Children's drawings -- Psychological aspects , Projective techniques for children , Psychological tests for children
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/4433 , vital:20669
- Description: This study aimed to establish the clinical utility of the Kinetic School Drawing (KSD) projective technique. It attempted to do so by using an existing self-report measure of children’s self-perceptions in the school environment (Harter’s Self-Perception Profile for Children) by which to corroborate the projections derived from the KSD’s. Following the development of this measure (in 1984) limited research has been undertaken to assess its validity, reliability and clinical utility despite promising initial findings. The KSD has therefore not received much attention and as a result, it has yet to be established as a useful psychological assessment tool. This study sought to revive interest and discussion around the KSD. Qualitative methods and specifically thematic analysis was employed to explore the usefulness of the KSD in an attempt to address the gap in the literature in a meaningful way. The sample consisted of 26 grade 5 learners from a private school in the Eastern Cape. The themes were presented under the following headings: scholastic competence, athletic competence, social competence, physical appearance and behavioural conduct.
- Full Text:
- Date Issued: 2017
The contribution of non-timber forest products to rural livelihoods and their price determination in different agro-ecological zones of South Africa
- Authors: Mugido, Worship
- Date: 2017
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/5176 , vital:20783
- Description: A large number of studies have been conducted on the contribution of different types of non-timber forest products (NTFPs) to rural livelihoods. However, not many of these have considered the context in which these contributions are made, especially agro-ecological potential. Similarly, there are few studies that focus on the price setting of NTFPs in different settings as most are based on a single or relatively few sites. Thus, there is no indication of the prevalence of the different factors within a uniform macro context, nor how they might vary between different types of NTFPs. Therefore, the aim of this thesis was to establish the contribution of NTFPs to rural livelihoods and their price determination in areas of varying agro-ecological potential of South Africa. The study used data from 1 200 randomly selected households across four agro-ecological zones of South Africa to quantify the contribution of NTFP income to total household income, the proportion of households selling at least a single NTFP and the nature and extent of use of NTFPs as safety nets in areas of varying agro-ecological potential. In addition, 300 sellers of NTFPs in 15 towns across South Africa were interviewed to assess the factors they take into account when setting prices. The findings of this study support the argument that the level of dependence on NFTPs varies with agro-ecological conditions. This was supported by the significant difference between the NTFP incomes of the following pairs of agro-ecological classes: very low and low, medium and high. About 6.4 % households reported selling one or more NTFPs for various reasons, with many (39 %) citing the need to earn cash income and limited employment opportunities (16.9 %). Income from trading NTFPs is undoubtedly an important source of cash income for many rural households. Thus, 300 sellers, selling either at home or in town, were interviewed and the majority (79.3 %) of the sellers reported that selling NTFPs was their main source of cash household income, with only 8 % and 5.7 % receiving their main cash household income from state child grants and state pension grants, respectively. The pricing factors considered by sellers when setting the prices of NTFPs tended to vary with the type of NTFP being sold, type of market (home markets or urban markets) and the method used by the seller to procure the stock. However, overall, transport costs (29 %), stock price (18.4 %), profit margin (12.7 %), time taken to collect or produce the product (7.3 %) and the market price (6.4 %) were the widely used factors to determine prices for NTFPs. The reported various pricing factors showed that there was no formal or certain price mechanism that was used by the sellers of NTFPs to establish the market prices of NTFPs. The study found that about 79 % of the total households interviewed experienced at least one shock of some magnitude in the previous 12 months. The most common shocks were illness (43 %), death (42 %), crop failure (29 %) and hunger (22 %). The households employed various coping strategies (21) in response to different types of shocks, with the three widely used strategies being assistance from friends and relatives (60.1 %), using cash savings (37.9%) and using NTFPs (35.6 %). Shocks, hunger or food shortage and crop failure were significantly and positively related to the usage of NTFPs as safety nets. Therefore, households who experienced hunger or food shortage and crop failure were likely to use NTFPs to cope with these shocks. The study concluded that NTFPs are an integral part of the rural livelihoods, especially for the households living close to the survival line.
- Full Text:
- Date Issued: 2017
The deductibility of damages and associated legal expenses for the purposes of determining taxable income in South Africa
- Authors: Madovi, Ezekiel
- Date: 2017
- Subjects: Income tax -- Law and legislation -- South Africa , Damages -- Taxation -- South Africa , South Africa. Income Tax Act, 1962
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/4344 , vital:20650
- Description: The deduction of damages and the associated legal costs must satisfy the requirements of the preamble to section 11 and section 11(a) of the Income Tax Act 58 of 1962, read with section 23(g) (referred to as the general deduction formula). This research examined under what circumstances a payer of damages and the associated legal costs would be able to claim a deduction from taxable income. This research also considered whether or not the issue of fault is a relevant consideration in determining whether a deduction should be allowed. In some cases the courts appear to have disallowed a deduction if the expenditure or loss was incurred as a result of a negligent or unlawful act. In other instances the courts have allowed the deduction of damages despite the expenditure or loss having been incurred as a result of a negligent or unlawful act. The research concludes that negligence is not a relevant consideration in the deduction of damages and the associated legal costs. In order to secure a claim for damages the taxpayer must prove that the expenditure was incurred in the production of income and it was expended for the purposes of trade. Associated legal costs are only deductible if the damages satisfy the requirements of section 11(c).
- Full Text:
- Date Issued: 2017
The determinants of credit default swap spreads in emerging market economies
- Authors: Matakane, Lwazi
- Date: 2017
- Subjects: Bank loans -- BRIC countries , Risk management -- BRIC countries , Swaps (Finance) -- BRIC countries , BRIC countries -- Economic conditions , Rating agencies (Finance)
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/7142 , vital:21221
- Description: Emerging markets have become a destination for international portfolio flows as a result of global financial integration. This has allowed exogenous factors like sentiment and developed country monetary policy to affect developing countries capital markets and macroeconomic fundamentals. This study analyses the impact of investor sentiment alongside US monetary policy, country specific risks, inflation and domestic stock returns on the BRICS credit default spreads. To investigate this relationship, the study uses panel data and a fixed effects model. The results of the panel regressions suggest that all variables had an impact on the variation of BRICS credit default spreads however the crisis may have distorted the relationship among the variables. Sovereign ratings had an inverse relationship depicting a rise in ratings decreasing the credit default premium. This was in line with a priori expectations. Domestic company earnings also had an inverse relationship with BRCIS credit default premia, the magnitude of which is dependent on the value of the index. This is to say the higher the index, the more significant the effect on the BRICS default premium. US monetary policy was significant and in line with expectations of a linear relationship between emerging market credit default spreads when controlling for the crisis. In the crisis period however, results depicted an inverse relationship going against a priori expectations. The inflation variable was found to have a greater impact on CDS spreads during the crisis period, while the VIX index had a linear relationship with the default premia albeit the impact was not highly significant. The study concludes that the financial crisis was an important event that affected the relationship of these variables with BRICS country default spreads and had read through to market participant’s behaviour at the time.
- Full Text:
- Date Issued: 2017
The development and institutionalisation of knowledge and knowledge-sharing practices relating to the management of healthcare risk waste in a home-based care setting
- Authors: Masilela, Mapula Priscilla
- Date: 2017
- Subjects: Medical wastes -- Management -- South Africa -- West Rand , Medical wastes -- Government policy -- South Africa -- West Rand , Environmental health -- South Africa -- West Rand , Environmental health -- Administration -- South Africa -- West Rand , Environmental health -- Government policy -- South Africa -- West Rand
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/13142 , vital:21807
- Description: Improperly managed healthcare risk waste is associated with environmental degradation due to its potential to pollute air, land and water; it also poses a public health threat due to risks to community members (adults and children) who may find themselves exposed to waste that has been disposed of improperly. Despite these obvious environmental health risks, there is little information or legislative guidance on how to effectively manage the healthcare risk waste generated by community health workers who move from house to house and do not operate out of a fixed clinic with formal waste management facilities. This poses a challenge for municipal environmental health practitioners who are mandated to ensure compliance and to monitor the management of healthcare risk waste by community home-based care facilities. This educational study looks at how the knowledge held by environmental health practitioners influences knowledge-sharing practices and management of healthcare risk waste by community health workers, and how these knowledge-sharing practices can be developed and institutionalised. The study takes an interventionist approach within the social constructionist tradition. Cultural- Historical Activity Theory (CHAT) and expansive learning provide the theoretical and methodological framework to surface systemic tensions and contradictions affecting knowledgesharing and healthcare risk waste management practices. A series of Change Laboratory Workshops using the Developmental Work Research methodology enabled a twenty-seven month expansive learning process with selected municipal employees and community health workers in a small South African city. The study found that employees (such as environmental health practitioners and waste inspectors) working in municipal activity systems knew very little about the forms and functions of community home-based care facilities in their municipality. As such, their knowledge-sharing practices about the management of healthcare risk waste were restricted and generally unsystematic, which in turn contributed to inappropriate and often haphazard healthcare risk waste management practices by community health workers. As an interventionist project, the study concluded that the participatory, expansive learning process it initiated had built knowledge-sharing networks, enabled professional boundary crossing and potentially institutionalised better knowledge-sharing practices relevant to the effective management of healthcare risk waste.
- Full Text:
- Date Issued: 2017
The development of biodegradable aerogel scaffolds for the generation of vascularised 3D adipose tissue models
- Authors: Makhene, Lebohang
- Date: 2017
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/59245 , vital:27492
- Description: Expected release date-April 2019
- Full Text:
- Date Issued: 2017
The development of techniques for the identification of novel viruses associated with acute infantile gastroenteritis in South Africa
- Authors: Jaquet, Brittany J
- Date: 2017
- Subjects: Gastroenteritis in children -- Treatment , Gastroenteritis in children -- Treatment -- South Africa , Antiviral agents , Viral vaccines , Rotaviruses , Virus diseases in children
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/38013 , vital:24725
- Description: Gastroenteritis is a serious disease affecting both children and adults globally, but is more predominant in children with over half a million deaths reported each year. The leading cause of this disease is rotavirus, which accounts for 38% of all hospitalised cases. There has, however, been a significant decrease in the number of deaths associated with rotavirus worldwide since the introduction of the two vaccines, Rotarix® and RotaTeq®. A large number of cases are therefore either associated with other viruses, such as norovirus, Aichi virus (AiV) or Saffold virus (SAFV), or are of unknown aetiology. This study thus aims to develop techniques for the identification of viruses associated with gastroenteritis. Theiler’s murine encephalomyelitis virus (TMEV) was used to develop the sample preparation, transmission electron microscopy and RT-PCR techniques used in this study. This virus was chosen as a replication system using baby hamster kidney cells can be used to create high concentrations of viral particles from which RNA can be extracted preventing the waste of the limited samples. The virus particles are also similar in size and morphology to the viruses to be identified in this study, as it belongs to the same family. After sample preparation, TEM analysis showed the presence of small, round, non-enveloped virus particles in the TMEV sample. Due to the low concentration of virus particles, PEG precipitation was performed using both 0.15 M and 0.25 M NaCl and 8% (w/v) PEG 6000. TEM analysis then showed an increase in viral particle concentration, with the highest concentration observed at 0.25 M NaCl and 8% PEG 6000. RNA was successfully extracted and RT-PCR assays were performed for both the VP1 and 2B coding regions of TMEV. A method for creating a positive control for the RT-PCR assay was developed by the in vitro transcription of RNA from pTMEV, which contains the cDNA of TMEV. The RNA was then used as the template for the 2B two-step RT-PCR assay. A product of 412 bp was successfully amplified from the in vitro transcribed RNA and the sensitivity of the RT-PCR assay was determined. Using a Norovirus GII positive stool sample provided by Maureen Taylor, a nested RT-PCR assay was developed for the NoV GII N/S domain using a previously-published primer set and cycling parameters. A 342 bp product was successfully amplified from the RNA extracted from the stool sample and cloned into pGEM®-T Easy to produce pNoVGII. Using the plasmid containing the AiV 5’UTR and the PCR amplicon for AiV 3CD, RT-PCR assays were developed for AiV 5’UTR and partial 3CD. The RT-PCR assays produced a 1008 bp product for AiV 5’UTR and 266 bp for AiV 3CD, which were cloned into pGEM®-T Easy to produce pAiV5’UTR and pAiV3CD, respectively. Using in vitro transcribed RNA from pNoVGII, pAiV5’UTR, pAiV3CD and pSAFV, which contains the SAFV cDNA, positive controls were developed for the RT-PCR assays for NoV GII, AiV 5’UTR, AiV 3CD and SAFV 2C. The sensitivity of these assays was determined. The samples chosen for this study include wastewater collected from the Belmont Valley water treatment plant, oysters suspected to be infected with viruses collected from Port Elizabeth, South Africa and 30 stool samples from symptomatic patients. With the methods developed using TMEV, the wastewater, oysters and 30 stool samples were filter-sterilised, concentrated and screened by TEM. All samples showed the presence of virus particles. RNA was successfully extracted and the wastewater, oyster and 30 stool samples were screened for NoV GII using the NoV GII RT-PCR assay. The wastewater, oysters and 11 of the stool samples produced the 342 bp NoV GII PCR product and BLAST analysis determined the nucleotide sequences to be NoV GII.4. This shows that this study was able to develop sample preparation techniques and TEM analysis for selected samples and RT-PCR assays for NoV GII, AiV and SAFV. The NoV GII RT-PCR assay was successfully used for the screening of the wastewater, oysters and 30 stool samples for NoV GII. Due to the high number of gastroenteritis cases with unknown aetiology in South Africa, the development of techniques for the identification of NoV, AiV, SAFV and other viruses is very important. The identification of these viruses will allow for better surveillance, treatment and prevention of gastroenteritis in South Africa.
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- Date Issued: 2017
The development, implementation and evaluation of a mental skills training programme for rowers at Rhodes University
- Authors: Wentworth, Tara E
- Date: 2017
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/5247 , vital:20797
- Description: In the ever increasingly competitive world of sport, there is a pressing need for training methods that have the potential to improve the performance of athletes. It is for this reason that practices associated with sport psychology (such as mental skills training) have increased in popularity. This desire for improved performance has seen a rising number of athletes seeking out the assistance of sport psychology methods. In this research, a mental skills training (MST) programme was developed and implemented into the training regime of Rhodes University rowers in Grahamstown, South Africa. The process of this research adhered to the Organisational Development Process Model’s format. Information collected from focus groups and performance profiling were utilised to design a MST programme tailored to the context of this group of athletes. This programme was implemented over one month and comprised of theoretical and practical sessions focussing on the topics of goalsetting, arousal regulation and imagery. After the programme had been completed, the participants evaluated the process in the form of individual interviews and were required to repeat the initial performance profile exercise. The results gathered from the various assessment and evaluation measures were used to compare and add to existing literature regarding MST and related disciplines. The benefits and effects of the programme have been detailed, and recommendations have been made which could possibly answer to the limitations of this research. These recommendations could provide insight into the manner in which MST programmes could possibly be more effectively implemented in future.
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- Date Issued: 2017