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South Africa’s mohair value chain: institutional framework, governance and the perceptions of management and labour

  • Authors: Heald, Arisa Oka
  • Date: 2020
  • Subjects: Management -- Employee participation , Management -- Employee participation -- South Africa , Agriculture -- South Africa -- History , Mohair industry -- South Africa , Mohair industry -- South Africa -- Employees
  • Language: English
  • Type: text , Thesis , Masters , MSocSci
  • Identifier: http://hdl.handle.net/10962/164669 , vital:41153
  • Description: The primary objective of this research is to understand the ways in which the (working and living) conditions confronting employers and employees on mohair farms are the complex outcome of their position in the global mohair value chain, the nature of the labour process, and the ‘contours of voice’ (i.e., how and why employees voice). These three bodies of literature represent different levels of analysis: at the broadest level, the political economy of the mohair value chain is explained by drawing on the chain literature. This literature has been supplemented, at the level of the production process, by deploying the concepts of labour process theory (LPT), which focus on the control of work processes by management as well as workers’responses to this control. These responses were analysed by incorporating insights from the burgeoning research on employee voice (EV) in an effort to understand the practical ways in which workers on mohair farms articulate their needs and interests. The cross-collination of these three bodies of literature is, to my knowledge, a novel feature of this research on the mohair industry in South Africa, which, in turn, has itself been woefully under-researched. The research design consisted of a qualitative approach in which I used in-depth, semi-structured interviews and focus-group discussions as the primary sources of data collection. The secondary source of data was available publications and documents from the agriculture industry and mohair sector. A qualitative approach acknowledges and gives great insight and meaning into the research topic. Twenty participants were interviewed for my research: six from key organisations within the mohair industry, ten farmers, two mohair farm workers and two mohair shearers. The main findings of the research include the following: first, institutions in South Africa’s mohair industry not only determine (in part) the structure of the mohair value chain but also play a vital role in governing the chain. Each institution and actor plays a significant role in adding value to the mohair product that leads to economic upgrading. Second, understanding the actions of farmers (as employers) by drawing on LPT allows me to show how the systemic pressures of capitalist accumulation compel employers to continuously enhance their control over production – and, by extension, over workers – who, in turn, resist and/or accommodate to these impositions by management. Lastly, the research shows that employee voice at the farm level is complex and contested – not surprisingly, given South Africa’s troubled history – yet, it is increasingly exercised by farm workers and accepted by mohair farmers as a necessary and inescapable means of resolving issues that arise in the employment relationship at the workplace and remaining competitive in a global market.
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  • Date Issued: 2020

Statutory mergers as contemplated in the Companies Act, 2008: the applicability of the corporate rules contained in section 44 of the Income Tax Act, 1962

  • Authors: Shama, Natalie Anne
  • Date: 2020
  • Subjects: South Africa. Companies Act, 2008 , South Africa. Income Tax Act, 1962 , Consolidation and merger of corporations -- South Africa , Corporation law -- South Africa
  • Language: English
  • Type: text , Thesis , Masters , MCom
  • Identifier: http://hdl.handle.net/10962/144767 , vital:38377
  • Description: The purpose of this research is to determine the extent to which a statutory merger in terms of the Companies Act, 2008, may be accommodated by the provisions of an amalgamation transaction in terms of section 44 of the Income Tax Act, 1962. The research method adopted is a legal interpretative research approach. South African company law underwent significant reform with the introduction of the Companies Act, 2008. One of the fundamental areas for reform was the need for a mechanism to appropriately accommodate a corporate merger, and thus, what is referred to as a statutory merger was introduced into South African company law. What is notable is that the statutory merger has been crafted to apply across a variety of circumstances that may arise in commerce, thus offering wide versatility. On the other hand, the tax relief afforded in terms of the corporate roll-over provisions in the Income Tax Act is designed to facilitate corporate transactions on a tax neutral basis, whilst balancing the concessions these measures introduce and the potential for tax avoidance. Consequently, the tax relief applicable to an amalgamation transaction will only apply within strictly prescribed parameters. The research shows an ongoing effort by National Treasury to amend the provisions of the amalgamation transaction to better accommodate a statutory merger, but highlights that there are nevertheless certain conflicting purposes (policy) for each piece of legislation. For these reasons, the focus and parameters of a statutory merger and amalgamation transaction do not align perfectly. The key areas of inconsistency identified in this research are threefold, namely (i) the creation of a new company as a consequence of a statutory merger is not accommodated in an amalgamation transaction; (ii) the process of compensating the shareholders of the amalgamated company in an amalgamation transaction is not clearly contemplated in the statutory merger provisions; and (iii) mergers between a company and its shareholder currently present numerous complexities from both a company law and taxation perspective. The research concludes that the flexibility afforded under the statutory merger is largely minimised for parties who wish to simultaneously enjoy the tax relief afforded under an amalgamation transaction.
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  • Date Issued: 2020

Structure and interaction studies of beta-amyloid in the search for new lead compounds for the treatment of Alzheimer’s disease

  • Authors: Mtini, Onke
  • Date: 2020
  • Subjects: Alzheimer's disease -- Chemotherapy , Alzheimer's disease -- Treatment , Amyloid beta-protein , Oxidative stress , Protein binding , South African Natural Compounds Database
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/167574 , vital:41493
  • Description: Alzheimer’s disease (AD) is the most devastating neurodegenerative disorder that effects the aging population worldwide. In this study three hypotheses of AD are explored, the β-amyloid cascade hypothesis, the β-amyloid metal binding hypothesis and the oxidative stress hypothesis are explored. In the first case compounds from the South African Natural Compounds Database (SANCDB) are docked to models of β-amyloid fibrils and the properties of these fibrils under pulling simulations are compared to a known small molecule disruptor of β-amyloid, wgx-50. In these simulations SANCDB compounds are identified that disrupt β-amyloid in a similar manner to wgx-50. In these simulations the disruption to the free energy of binding of chains to the fibrils is quantified. For metal binding and oxidative stress hypotheses, problems in simulation arise due to only fragments of β-amyloid being present in the Research Collaboratory for Structural Bioinformatics protein data bank (RCSB PDB), as determined from NMR experiments. In this work, β-amyloid is set up under periodic boundary conditions to simulate a fibril under reasonable computational time. Within these periodic boundary conditions, β-amyloid has been solvated in copper and zinc rich environments and diffusion of these metals around the fibrils has been explored. The localization of these metals (in simulation only using van der Waal’s and electrostatic terms) around the fibril has led us to explore other possible metal binding sites. Metal bound to the infinite fibril has been optimized at the QM/MM level and some of the reactive oxygen species in the presence of the fibril are quantified.
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  • Date Issued: 2020

Symmetry and asymmetry in electrocatalysis: enhancing the electrocatalytic activity of phthalocyanines through synergy with doped graphene quantum dots

  • Authors: Nkhahle, Reitumetse Precious
  • Date: 2020
  • Subjects: Phthalocyanines , Quantum dots , Graphene
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/117585 , vital:34529
  • Description: An exploration on the enhancement of the electrocatalytic activity of phthalocyanines (Pcs) through coupling with a series of graphene quantum dots (GQDs) is undertaken. The preliminary studies using symmetrical Pcs, a cobalt and an iron chloride tetra substituted diethylaminophenoxy Pc (complexes 1 and 2), for the electro-oxidation of nitrite revealed through the various sequential modifications that doped GQDs fare better than their pristine counterparts with respect to improving the electrocatalytic behaviour of Pcs, in particular, the nitrogen-doped GQDs (NGQDs). Following up on this, a series of asymmetric Pc complexes; 2,9,16-tris-(4-tert-butylphenoxy) mono carboxyphenoxy phthalocyanato cobalt (II) (3), 2,9,16-tris-(4-tert-butylphenoxy) mono aminophenoxy phthalocyanato cobalt (II) (4), 2,9,16-tris-(3-diethylamino)phenoxy) mono carboxyphenoxy phthalocyanato cobalt (II) (5) and 2,9,16-tris-(3-diethylamino)phenoxy) mono aminophenoxy phthalocyanato cobalt (II) (6) was prepared in which push-pull systems were compared to other asymmetric complexes that lack this effect towards the electrocatalytic sensing of hydrazine. All asymmetric complexes (3-6) were π-stacked to the NGQDs while those with an NH2 group (4 and 6), were also covalently linked to the NGQDs. These complexes and their corresponding conjugates were characterized accordingly and applied as electrocatalysts in the oxidation of hydrazine. The electrochemical studies revealed that π π stacking yields better responses (higher sensitivities and lower limits of detection) than covalent linking because there are less forces acting on the graphene network. Covalent linking introduces both tensile and compressive forces which in turn results in an increase in the ID/IG ratio and that is unfavourable for electrocatalysis. In comparing the electrodes composed of the π-stacked conjugates to those altered through sequential modifications, despite the conditions not being the same, it can be inferred that the magnitude of the electrostatic forces between the Pcs and the GQDs also plays a significant role in electrocatalysis. The π-stacked conjugates, owing to the manner in which they were prepared, have stronger electrostatic forces acting between the Pc and GQDs hence they were able to elicit a better electrochemical response than the sequentially modified electrodes. In addition to that, it appears that asymmetric Pcs are better electrocatalysts in comparison to the symmetric Pcs.
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  • Date Issued: 2020

Synthesis and in vitro biological evaluation of 2,3-substituted quinoline derivatives

  • Authors: Bokosi, Fostino Raphael Bentry
  • Date: 2020
  • Subjects: Quinoline , Malaria Chemotherapy , Tuberculosis Chemotherapy , African trypanosomiasis Chemotherapy
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10962/163193 , vital:41017
  • Description: The urgent need for new systemic pharmacological entities prompted us to report a library of 2,3-substituted quinoline derivatives. Considering the ubiquity of quinoline-containing compounds in pharmacologically active small molecules, synthesized 2,3-substituted quinoline derivatives were in vitro biologically evaluated for their potential antitubercular, antimalarial and antitrypanosomal activities. Quinoline scaffold was achieved by the Vilsmeier-Haack methodology, affording synthetically useful chloro and formyl substituents on C-2 and C-3 respectively. These two substituents acted as handles in expanding the chemical space around the quinoline ring. Target compounds were synthesized in six to seven steps, employing conventional synthetic organic protocols adapted from various literature. The final compounds were accessed in moderate to good yields. The structural identity of each compound was confirmed by common spectroscopic techniques. Aryl quinoline carboxamide derivatives 3.113 – 3.126 were isolated as rotamers, hence, Variable-Temperature Nuclear Magnetic Resonance (VT-NMR) was employed in resolving 1H splitting. At elevated temperature (~328 K); N-methylene carbons were not visible on 13C NMR due to signal line broadening effects. The presence of these nuclei in such cases was, however, supported by 2-dimensional NMR and high-resolution MS data. Most of the compounds achieved in this study displayed promising antimalarial activity against chloroquine-sensitive 3D7 strain of Plasmodium falciparum compared to antitrypanosomal activity against Trypanosoma brucei brucei 427 strain. In particular, compounds 3.80 and 3.108 showed superior activity against chloroquine-sensitive 3D7 P. falciparum strain with IC50 values < 1 μM. More importantly, most of the compounds were non-toxic as determined by HeLa cells, indicating their selectivity towards the parasites. Exploring the space provided on the quinoline scaffold revealed that methoxy incorporation on C-2 is very critical in enhancing antimalarial activity of this class of quinoline compounds. The preliminary SAR of compounds 3.57 – 3.72 showed that compounds containing the 3-cinnamate exhibited enhanced antimalarial activity compared to 2 and 4-cinnamates. Finally, benzamide compounds 3.113 − 3.126 showed poor activity against Mycobacterium tuberculosis H37Rv strain with only compounds 3.113, 3.117 – 3.120 and 3.126 showing appreciable MIC90 values in the range of 40 – 85 μM. , Thesis (MSc) -- Faculty of Science, Chemistry, 2020
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  • Date Issued: 2020

Synthesis of novel heterocyclic systems as potential inhibitors of HIV-1 enzymes

  • Authors: Sekgota, Khethobole Cassius
  • Date: 2020
  • Subjects: Protease inhibitors , Heterocyclic compounds , HIV (Viruses) , Quinoline , Amides , Nuclear magnetic resonance , Antiretroviral agents , AIDS vaccines , Nitrobenzaldehyde , Propylphosphonic acid anhydride
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/146502 , vital:38531
  • Description: This study has focussed on the application of Baylis-Hillman methodology in the development of efficient synthetic pathways to libraries of novel 3-[(N-cycloalkylbenzamido)methyl]-2-quinolones and indolizine-2-carboxamides and on an exploration of their medicinal potential. The approach to 3-[(N-cycloalkylbenzamido)methyl]-2(1H)-quinolones involved a six-step pathway comprising: Baylis-Hillman reaction of 2-nitrobenzaldehyde derivatives and methyl acrylate to afford nitro-Baylis-Hillman adducts; thermal cyclisation of the adducts to give a range of 3-(acetoxymethyl)-2(1H)-quinolones in good to excellent yields; hydrolysis of the acetates; conversion of the resulting alcohols to the 3-chloromethyl analogues; amination; and, finally, acylation to afford the target amides. Variable temperature NMR methods were used to facilitate analysis of the ¹H and ¹³C NMR spectra which were complicated by internal rotation and cycloalkyl ring-flipping effects. On the other hand, the indolizine-2-carboxamides were obtained in several steps commencing with the Baylis-Hillman reaction of pyridine-2-carboxaldehyde and methyl acrylate. Thermal cyclisation of the Baylis-Hillman adduct afforded indolizine esters, hydrolysis of which gave the corresponding acids which served as precursors to the target indolizine-2-carboxamides. The final amidation step, however, proved to be particularly challenging. Various coupling strategies were explored to access indolizine-2-carboxamides. These included the use of 2,2,2-trifluoroethyl borate which showed limited promise, but propylphosphonic acid anhydride (T3P) proved to be the most effective coupling agent, permitting the formation of 24 novel indolizine-2-carboxamides from hydrazines, aliphatic amines and a range of heterocyclic amines. A high-field NMR-based kinetic study of the mechanism of the Baylis-Hillman reaction of pyridine-4-carboxaldehyde and methyl acrylate in the presence of 3-hydroxyquinuclidine in deuterated chloroform was initiated, reaction progress being followed by the automated collection of ¹H and DEPT 135 NMR spectra over ca. 24 hours using a high-field (600 MHz) NMR instrument. The results have provided critical new insights into the mechanism. NMR analysis has also been used to elucidate the multiplicity of signals associated with rotameric equilibria observed at ambient probe temperature. Variable temperature 1D- and 2D-NMR spectra were used to facilitate the unambiguous characterisation of the 2-quinolone benzamides and some of the indolizine-2-carboxamides. The 3-[(N-cycloalkylbenzamido)methyl]-2(1H)-quinolones, together with selected precursors, and a number of the indolizine-2-carboxamides have been screened in vitro as potential HIV-1 enzyme inhibitors. A survey of the activity of the 2-quinolones against HIV-1 integrase, protease and reverse transcriptase revealed selective inhibition of HIV-1 integrase with the most active IN inhibitor, 3-[(cyclopentylamino)methyl-6-methoxy-2(1H)-quinolone 115e, producing residual enzyme activity of 40% at a concentration of 20 μM. Many of the 2-quinolones exhibited no significant cytotoxicity against HEK 293 cells at 20 μM concentrations. 3-[(N-Cyclohexylamino)methyl]-6-methoxy-2(1H)-quinolone 114e was the only compound to exhibit ant-plasmodial activity (55% pfLDH activity). The survey of indolizine-2-carboxamides also revealed encouraging inhibition against HIV-1 integrase. None of these compounds exhibited cytotoxicity at 20 μM against HEK 293 cells, while a number of them exhibited some activity against Plasmodium falciparum (3D7 strain) and Trypanosoma brucei. Selected indolizine-2-carboxamides exhibited significant anti-tubercular activity in the 7H9 CAS GLU Tx and 7H9 ADC GLU Tw media. In view of the inherent fluorescent character and biological potential of the synthesised indolizine-2-carboxamides, their photophysical properties were explored to establish their possible dual use as bio-imaging and therapeutic agents. The major absorption and corresponding emission bands, and the associated molar absorption coefficients (Ɛ) expressed in the form of log Ɛ were determined. Their high extinction coefficients, large Stokes shift and red-shifted emissions in the visible region indicate their potential for use as fluorophores.
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  • Date Issued: 2020

Synthesis of peptidomimetic compounds as HIV-1 protease inhibitors

  • Authors: Kayembe, Jean-Pierre
  • Date: 2020
  • Subjects: Protease inhibitors , HIV (Viruses) , HIV infections Treatment , Peptidomimetics‎
  • Language: English
  • Type: Doctoral theses , text
  • Identifier: http://hdl.handle.net/10962/124397 , vital:35604 , DOI https://dx.doi.org/10.21504/10962/124397
  • Description: This research project has involved the design, synthesis and evaluation of novel peptidomimetics compounds as HIV-1 protease inhibitors. Here is presented one-step, two-step and three-step syntheses and the in vitro bio-assay studies of a series of fully characterized peptidomimetics as HIV-1 protease inhibitors candidate using the shortest and most cost effective synthetic routes. The first series of compounds were accessed via a synthetic elaboration of Morita-Baylis-Hillman adducts by a Michael addition with benzylamine, proline or glycine esters to afford a series of β-amino-β’-hydroxycarboxylate esters in moderate to good yields. Base-catalyzed cyclization of non-benzylated aza-Michael adducts afforded a series of coumarin-3-hydroxy-2-methylenepropanoate esters in moderate yields. The uncatalyzed direct amidation of diethyl tartrate/tartaric acid and tartaric acid osazone with selected amines/amino acids afforded a series of C2-symmetrical and unsymmetrical 1,2-dihydroxycarboxylates in moderate to very high yields. All the synthesized compounds were fully characterized using spectroscopic techniques. These conjugates, designed as potential HIV-1 inhibitors, were tested against the HIV-1 protease enzyme. A number of these ligands have exhibited inhibition levels and IC50 values comparable to ritonavir, permitting, therefore, their identification as lead compounds for the development of novel inhibitors. , Thesis (PhD) -- Faculty of Science, Chemistry, 2020
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  • Date Issued: 2020

Synthesis, characterisation and electrocatalytic behaviour of three series of Metal Organic Frameworks

  • Authors: Murinzi, Tafadzwa Wendy
  • Date: 2020
  • Subjects: Electrochemistry , Metal-organic frameworks , Polyoxometalates , Fourier transform infrared spectroscopy , Electrocatalysis , Cysteine
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/167598 , vital:41495
  • Description: Metal organic frameworks (MOFs) have received a lot of attention over the past few years due to their vast range of interesting properties and applications, such as catalysis, environmental sensing and storage. This wide range of potential applications is afforded by careful selection and manipulation of the components chosen in assembling of MOFs. In this study, three series of MOFs were synthesized from Co(II), Cu(II) and Mo(VI) polyoxometallates with either 1,3,5-benzenetricarboxylic acid, 1,2,4,5-benzenetetracarboxylic acid or 2,6- pyridinedicarboxylic acid as the ligands. In series 1, the common 1,3,5- benzenetricarboxylic acid MOF, HKUST-1, and POM modified HKUST-1 compounds involving encapsulation and encorporation of the POM were utilised. In series 2, flexible cobalt(II) benzenepolycarboxylate MOFs which investigated the effect of varying the degree of carboxylate substituent were utilised. In series 3, flexibly reduced heterocyclic polycarboxylate MOFs using 2,6-pyridine dicarboxylate were utilised. Solvothermal and slow evaporation synthesis conditions were employed. Where single crystals of good quality were produced, single crystal X-ray diffraction (SC-XRD) was employed for structural elucidation. In the absence of such crystals, a combination of elemental analysis, inductively coupled plasma optical emission spectrometry (ICP-OES) and powder X-ray diffraction (PXRD) was used. Characterization of the MOFs was done by Fourier transform infrared spectrometry (FTIR) and thermal methods, namely thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The electrocatalytic potential of the compounds in the oxidation of L-cysteine was then investigated using a variety of techniques. Cyclic voltammetry was used for L-cysteine detection whilst chronoamperometry and differential pulse voltammetry were used to determine the nanoprobes’ sensitivity, rate constants and detection limits. Electrochemical impedence spectroscopy was used to investigate the charge transfer resistance (RCT) and electron transfer kinetics. Of the three, series 3 gave the best signals and sensitivities for electrocatalysis of L-cysteine followed by series 2 and lastly series 1. Series 2 showed the highest stability and series 1 required the least overpotential. The results highlight the effects of different metal centres and ligands on electrocatalysis. The application of MOFs in electrochemistry is a relatively new field making the findings of this study a significant addition to the body of knowledge.
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  • Date Issued: 2020

Synthesis, photophysicochemical properties and photodynamic therapy activities of indium and zinc phthalocyanines when incorporated into Pluronic polymer micelles

  • Authors: Motloung, Banele Mike
  • Date: 2020
  • Subjects: Indium , Zinc , Phthalocyanines , Polymers , Photochemotherapy , Micelles
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/167529 , vital:41489
  • Description: This thesis reports on the syntheses, photophysicochemical properties and photodynamic therapy activities of symmetrical metallophthalocyanines (MPcs) when alone or when incorporated into Pluronic polymer micelles. The Pcs contain either zinc or indium as central metals and have phenyldiazenylphenoxy, pyridine-2-yloxy and benzo[d]thiazol-2-ylthio as ring substituents. Spectroscopic and microscopic techniques were used to confirm the formation MPcs with micelles. The photophysics and photochemistry of the Pcs were assessed when alone and with micelles. All the studied Pcs showed good photophysicochemical behavior with relatively high triplet and singlet oxygen quantum yields corresponding to their low fluorescence quantum yields. The Pcs with indium in their central cavity exhibited higher triplet and singlet oxygen quantum yields in comparison to their zinc counterparts due to the heavy atom effect obtained from the former. The in vitro dark cytotoxicity and photodynamic therapy of the Pc complexes and conjugates against MCF7 cells was tested. All studied Pc complexes alone and with micelles showed minimum dark toxicity making them applicable for PDT. All complexes displayed good phototoxicity < 50% cell viability (except for complex 2 > 50% cell viability) at concentrations ≤100 μg/mL, however the conjugates showed < 45% cell viability at concentrations ≤ 100 μg/mL, probably due to the small micellar size and EPR effect. The findings from this work show the importance of incorporating photosensitizers such as phthalocyanines into Pluronic polymers micelles and making them water soluble and ultimately improving their photodynamic effect.
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  • Date Issued: 2020

System analysis of fatigue in pilots and co-pilots executing short-hall flight operations

  • Authors: Bennett, Cleo Taylor
  • Date: 2020
  • Subjects: Air pilots -- Health and hygiene , Fatigue , Work environment -- Psychological aspects , Work environment -- Physiological aspects
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/146622 , vital:38543
  • Description: Background: This study was conducted as part of Denel’s South African Regional Aircraft (SARA) development project. Regional aircraft have a maximum flight time of 60 minutes. Hence, the study focuses on matters pertaining to the short-haul flight context. Pilot fatigue has been recognised as a safety concern in the aviation industry. It impacts on pilot performance across the board, not least in the short-haul context. However, the specific factors that lead to pilot fatigue in short-haul operations have not been well researched. Research Aim: To identify and examine the factors which influence pilot/co-pilot fatigue in short-haul aviation contexts. Method: Fatigue is multifaceted, and has multiple definitions and descriptions. It is acknowledged as a complex phenomenon, the development of which is dynamically influenced by various factors. Thus, a systems approach based on the work system model by Smith and Carayon-Sainfort (1989) was adopted for this study. A systems analysis was conducted in two parts: 1) a literature analysis, and 2) expert interviews. Results: Both the literature analysis and the interviews indicated that pilot fatigue in short-haul flight operations represent composite system outcomes influenced by various factors. The factors identified were structured (systematised) into categories, namely organizational factors, task-related factors, environmental factors, factors linked to technology and tools, and non-work-related factors specific to the individual pilot. An example of a task-related factor would be the performance by pilots of multiple take-offs and landings; organizational factors include work time arrangements and duty scheduling (e.g. unpredictable schedule, early starts/late finishes, number of flight sectors in a shift, extended working hours, numerous consecutive work days, standby duties, flight, duty and rest limitations (regulations and guidelines); and short turnaround periods); environmental factors might include the small pressurised cockpit environment, movement restriction, very low humidity, low air pressure, vibrations, high noise levels, low light intensity light, and inclement weather); there are many examples of how tools and technology utilized by pilots might affect their fatigue levels; and finally, pilot-specific non-work-related factors would include things like the pilot’s age, health (lifestyle), family stress, work experience and sleep environment. All of these factors were identified during the literature analysis and have a significant bearing on how fatigue could present in short-haul pilots/co-pilots. Other important fatigue-related factors revealed during the expert interviews included, organizational culture, time management, health implications of fatigue, and management of fatigue. Conclusions: Pilot fatigue is a complex and multi-factorial physiological condition. There are many interacting components which contribute to pilot fatigue in short-haul operations. These should be viewed from an integrated perspective and holistic, systems-based approaches should be taken to manage these issues, particularly in the context of short-haul operations. This would optimize pilot performance and well-being and, most importantly, improve the safety of the work environment to enhance overall operation safety. Limitations: The study does not quantify the contributions made to pilot fatigue by the various factors explored. Therefore, care needs to be taken when designing and implementing interventions based on this research.
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  • Date Issued: 2020

Tax revolts: an international perspective

  • Authors: Tinotenda, Tariro Chizanga
  • Date: 2020
  • Subjects: Taxation -- Public opinion , Taxation -- Law and legislation -- South Africa , Income tax -- South Africa , South Africa -- Economic conditions , Fiscal policy -- South Africa
  • Language: English
  • Type: text , Thesis , Masters , MComm
  • Identifier: http://hdl.handle.net/10962/166116 , vital:41330
  • Description: The main goal of this study is to investigate whether tax revolts currently taking place and apparently threatening to take place in South Africa follow patterns shown in past international tax revolts or follow a unique pattern of their own. Tax revolts or tax rebellions are not a new phenomenon; they can be traced back to the beginning of time. Renowned tax revolts of the past include the Magna Carta and the Peasants’ Revolt in England, the Boston Tea Party, the Whiskey Rebellion, the Zimbabwean poll tax revolt, the Bambatha rebellion, the Tigre Rebellion, Proposition 13 and Margaret Thatcher’s poll tax revolt. These tax revolts were usually caused by the high burden of taxation, excessive government expenditure, corruption of government officials, declining tax morale of taxpayers and taxpayers’ perceptions of unfairness. In South Africa, elements of tax revolts have been on the rise. There has been a tax revolt against the e-tolling system in Gauteng since 2013. Non-payment of municipal rates is another form of tax revolt that has been and is happening in South Africa. Trade unions have also threatened strikes and mass action against various tax changes, including the value-added tax increase. Taxpayers, through media reporting, have been witnessing an increase in the use of taxpayers’ money for non-governmental agendas or overstated budgets. An increasing number of South Africans have been emigrating financially from South Africa to avoid a high taxation burden. The study falls within a post-positivist paradigm and an interpretive methodology is applied in the present research. The methodology is based on the fact that the social reality of tax revolts is not singular or objective, instead it is influenced by human experiences and social contexts. The study finds that tax revolts are currently occurring and threatening to occur in South Africa. The patterns of South African tax revolts are to a great extent similar to the patterns of international tax revolts, indicating the universalism of tax revolts. The study also confirms that South African tax revolts are, to a certain extent, unique.
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  • Date Issued: 2020

Taxonomic revision of the Natal mountain catfish, Amphilius natalensis (Siluriformes, Amphiliidae) in southern Africa

  • Authors: Mazungula, Daniel Nkosinathi
  • Date: 2020
  • Subjects: Uncatalogued
  • Language: English
  • Type: thesis , text , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/164490 , vital:41123
  • Description: Thesis (MSc)--Rhodes University, Department of Ichthyology and Fisheries Science, 2020
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  • Date Issued: 2020

Teachers’ perceptions, experiences and challenges related to using ICTs in teaching Social Sciences in marginalised classrooms in the Eastern Cape Province, South Africa

  • Authors: Gunzo, Fortunate Takawira
  • Date: 2020
  • Subjects: Educational technology -- South Africa -- Eastern Cape , Teachers -- In-service training -- South Africa -- Eastern Cape , Social sciences -- Study and teaching -- South Africa -- Eastern Cape , Information technology -- South Africa -- Eastern Cape , Technological innovations -- Employee participation -- South Africa -- Eastern Cape , Teachers -- Attitudes , Technological innovations -- Economic aspects -- South Africa -- Eastern Cape , Technology Acceptance Model , Teacher Cognitions theory
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/146964 , vital:38581
  • Description: This study seeks to examine teachers’ perceptions and experiences of using Information and Communication Technology (ICT) in teaching as the basis for actual use in the classroom. I conducted an eclectic study with a multidisciplinary theoretical viewpoint combining theories from Information Technology (IT) and education to examine how perceptions and prior experiences with ICT influence cross-curriculum ICT integration. Specific aspects of five theories and models were used in different phases of this study. I drew on the Technology Acceptance Model (TAM) and Teacher Cognitions theory to understand teachers’ perceptions towards ICT in general and towards ICT in the classroom. The classroom observations were conducted using an observation guide informed by Activity theory. I then utilised the Adoption of Innovation and the Diffusion of Innovation theories to explain why and how ICT was utilised in the classrooms. A mixed methods research approach located within a pragmatic paradigm was chosen. Three data sets were collected. First, a questionnaire of attitudes and perceptions towards ICT was conducted with 183 teachers (mainly working at marginalised schools in the Eastern Cape Province of South Africa). Questionnaire data was analysed using descriptive statistics and a chi-square correlations test. Second, teachers enrolled in an in-service Advanced Certificate in Education specializing in ICT (ACE-ICT) at Rhodes University were supported in planning and implementing an intervention involving the use of a mobile computer lab in rural and peri-urban schools. Three key participants were observed while teaching in class using ICT for the first time and they were subsequently interviewed. Third, drawing from lessons learnt from this experience, students in the in-service education bachelor’s degree in ICT (BEd-ICT) – which replaced the in-service ACE-ICT – were supported and encouraged to experiment with cross-curriculum integration using ICT already at their disposal. Planning and reflections by three in-service BEd-ICT teachers were subjected to theory-based document thematic analysis. Findings indicate that the vast majority of the teachers had positive attitudes towards ICT and perceived ICT as useful, mainly as a productivity tool in teaching. ICT was used mostly for administration, planning and preparation of lessons and not for teaching or as a cognitive tool. Despite all key participants having access to similar ICTs and support, their experiences of teaching with ICT were different based on their personal commitment, access to and frequency of use of ICTs in their personal lives. Teachers who were self-motivated to use ICT in their teaching made efforts to do so regardless of infrastructure and resource challenges they faced at their schools. The main barriers to the use of ICT in the classroom appear to be lack of technical support and time constraints.
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  • Date Issued: 2020

Technology in conservation: towards a system for in-field drone detection of invasive vegetation

  • Authors: James, Katherine Margaret Frances
  • Date: 2020
  • Subjects: Drone aircraft in remote sensing , Neural networks (Computer science) , Drone aircraft in remote sensing -- Case studies , Machine learning , Computer vision , Environmental monitoring -- Remote sensing , Invasive plants -- Monitoring
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/143408 , vital:38244
  • Description: Remote sensing can assist in monitoring the spread of invasive vegetation. The adoption of camera-carrying unmanned aerial vehicles, commonly referred to as drones, as remote sensing tools has yielded images of higher spatial resolution than traditional techniques. Drones also have the potential to interact with the environment through the delivery of bio-control or herbicide, as seen with their adoption in precision agriculture. Unlike in agricultural applications, however, invasive plants do not have a predictable position relative to each other within the environment. To facilitate the adoption of drones as an environmental monitoring and management tool, drones need to be able to intelligently distinguish between invasive and non-invasive vegetation on the fly. In this thesis, we present the augmentation of a commercially available drone with a deep machine learning model to investigate the viability of differentiating between an invasive shrub and other vegetation. As a case study, this was applied to the shrub genus Hakea, originating in Australia and invasive in several countries including South Africa. However, for this research, the methodology is important, rather than the chosen target plant. A dataset was collected using the available drone and manually annotated to facilitate the supervised training of the model. Two approaches were explored, namely, classification and semantic segmentation. For each of these, several models were trained and evaluated to find the optimal one. The chosen model was then interfaced with the drone via an Android application on a mobile device and its performance was preliminarily evaluated in the field. Based on these findings, refinements were made and thereafter a thorough field evaluation was performed to determine the best conditions for model operation. Results from the classification task show that deep learning models are capable of distinguishing between target and other shrubs in ideal candidate windows. However, classification in this manner is restricted by the proposal of such candidate windows. End-to-end image segmentation using deep learning overcomes this problem, classifying the image in a pixel-wise manner. Furthermore, the use of appropriate loss functions was found to improve model performance. Field tests show that illumination and shadow pose challenges to the model, but that good recall can be achieved when the conditions are ideal. False positive detection remains an issue that could be improved. This approach shows the potential for drones as an environmental monitoring and management tool when coupled with deep machine learning techniques and outlines potential problems that may be encountered.
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  • Date Issued: 2020

Temporal patterns and seasonal variation in microplastic loads in the water column and in the tissues of consumers along the southern and south-eastern coasts of South Africa

The archival turn: rereading the Guy Butler Collection in the National English Literary Museum

  • Authors: Wyrill, Beth
  • Date: 2020
  • Subjects: National English Literary Museum (South Africa) , Butler, Guy, 1918-2001 , Archives -- South Africa , Archives -- Philosophy , Memory (Philosophy)
  • Language: English
  • Type: Thesis , Doctoral , PHD
  • Identifier: http://hdl.handle.net/10962/145746 , vital:38463
  • Description: This thesis takes as its theoretical springboard the ‘archival turn’ in South African historical studies, a moment that arguably reached its culmination in 2002 with the publication of Refiguring the Archive. The archival turn posits that, rather than using it as an unproblematic source of original material, scholars might begin to investigate the archive itself, including its processes of construction and organisation. This theoretical model also proposes that the archive might reflect the cultural beliefs and epistemologies common to the era in which it was set up. It seems that the time is ripe for a reconsideration of the insights gleaned from this academic moment in South Africa, given the recent contestation over the meanings of history and our cultural markers of heritage in the public domain, largely grouped under the term ‘Fallism.’ As such, a fresh look at South African museums, which in this country are often rooted in colonial practices of knowledge production, seems apt. This work uses the case of Guy Butler, founder of many South African English cultural institutes and arts bodies, as a conduit and lens for thinking through these problematics. One of Butler’s institutional ‘offspring,’ born from his overarching work on behalf of the English cultural and literary cause in South Africa in the twentieth century, is the National English Literary Museum (NELM). Investigating the founding context and practices of NELM is a useful way of exploring the impact of Butler’s life’s work on literary heritage in South Africa. Issues such as the way in which NELM and Grahamstown continue to signify as loci of thought and practice in the contemporary South African literary landscape will be addressed. The study draws extensively on the Butler collection at NELM, and spends much time investigating Butler’s positioning in a South African literary historical context in the twentieth century, to better understand the forces at work during the time of NELM’s coming-into-being. Derrida’s seminal work on the function of archives, in Archive Fever, is mined for a theoretical basis for the study, as is Deleuze and Guattari’s thought on how bodies (taking the NELM institution here to represent a ‘body’) form, change, and interact, explicated in the work A Thousand Plateaus. The study offers some insights into how the NELM archive was formed, and which forces continue to shape its work in the South African spheres of English literature and heritage.
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  • Date Issued: 2020

The benefits and challenges of implementing the Equator Principles: the case of four large banks in South Africa, through the eyes of project finance teams

  • Authors: Baloyi, Glenda
  • Date: 2020
  • Subjects: Financial institutions -- South Africa -- Moral and ethical aspects , Sustainable development -- South Africa , Project management -- South Africa -- Finance
  • Language: English
  • Type: text , Thesis , Masters , MBA
  • Identifier: http://hdl.handle.net/10962/126165 , vital:35855
  • Description: The purpose of this research was to investigate the benefits and challenges of implementing the Equator Principles (EPs) by the four large banks in South Africa who are signatories to the framework. This was investigated through the eyes of the project finance teams. The research focused on the perceptions of the project finance team. The EPs are voluntary standards, to date they have been adopted by 94 financial institutions. Financial institutions that have adopted the EPs, benefit by having a competitive advantage of getting involved with high risk projects / developments. The Equator Principles resulted in having environmental and social risk policies and structures to manage these risks. This research was conducted using mixed methods and followed the post-positivist paradigm. The research found that the project finance teams were aware of the environmental, social and governance risks associated with project finance transactions. Furthermore, they understood the need to have the Environmental, Social and Governance (ESG) risk assessment during the credit process. This research found out that the benefits of the EPs outweigh the challenges, as they promote responsible investment, thus promoting the reputation of the investor. The EPs requires the client / borrower to conduct an environmental and social impact assessment and commit to covenants that are binding in the financial legal agreements. By having processes and strategies that promote responsible investment in the financed projects / development, this gives the Equator Principles Financial Institution (EPFI) the advantage of competing in the international market. EPs may indirectly influence the financial institutions that have not adopted the EPs, to promote responsible investment by applying ESG risk assessment processes as required by the banks that have adopted the EPs. EPs lack of capacity such as human resources, policies, funds and structures is the reason why companies do not adopt responsible investment is their operation and not incorporating them in the decision-making process. Some EPFI are not committed the EPs and become free riders. Other EPFI are not complying with the EPs and this causes uncertainties with regards to the legitimacy of the ES standards. EPs are ambiguous, subjective and voluntarism can make it difficult to be achieved by the EPFI. EPs increases the approval process for the financial institution to conclude the transaction, thus delaying the start of a needed project / development. And that EPFI may be forced to have fewer clients as a result of the funding requirements required by EPs.
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  • Date Issued: 2020

The catchup games: a novella

  • Authors: Nstumpa, Siya
  • Date: 2020
  • Subjects: South African fiction (English)
  • Language: English
  • Type: text , Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/167222 , vital:41448
  • Description: Creative work portfolio.
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  • Date Issued: 2020

The current nature of intra-regional trade in the proposed tripartite free trade area

  • Authors: Chibuta, Chisengele
  • Date: 2020
  • Subjects: Customs unions -- Africa, Southern -- Economic integration , Africa, Southern -- Economic policy , Africa, Southern -- Economic integration , Africa, Southern -- Economic conditions , Tripartite Free Trade Area , Free trade -- Africa, Southern
  • Language: English
  • Type: Thesis , Masters , MCom
  • Identifier: http://hdl.handle.net/10962/146744 , vital:38553
  • Description: This thesis examines and analyses the current nature of intra-regional trade between member states of the proposed Tripartite Free Trade Area in order to contribute to an understanding of the potential for intra-regional trade within the region to increase. Trade Complementarity Indexes were used to determine how well the structures of the three founding blocs’ major imports and exports match. The results show that there is a high degree of trade complementarity in the trade of the top 5 major products traded between the regional groups. With the proposed TFTA in place, high trade complementarity could lead to increased trade between the regional groups. Trade Intensity Indexes were used to determine how intensively the three founding blocs trade with one another. Results from the indexes help determine the extent to which the blocs currently view each other as important trading partners and the implications of this for the proposed TFTA. Results show that EAC and SADC as well as EAC and COMESA viewed each other as significant trading partners while SADC and COMESA did not for the majority of the years from 2001 to 2018. With the TFTA in place, intra-regional trade could be strengthened among the members who currently trade intensively because tariffs between them would be progressively eliminated as required by the TFTA Agreement. Revealed Comparative Advantage Indexes were used to gain insights on whether member states have any comparative advantage in their top 5 exports. Results from the indexes were used to determine whether member states have comparative advantage in similar or dissimilar major exports and the implications of this for the proposed TFTA. Results show that member states have revealed comparative advantage in similar products and these products present opportunities for joint-production among member states as well as sectors for product development once the proposed TFTA is in place. Revealed Trade Barrier Indexes were used to gain insights into the extent of ease of market access into each regional bloc’s market. Results from the indexes indicate whether major products imported from each other receive possibly discriminatory or preferential treatment. The results indicate that the majority of the top 5 imports sourced from each region receive preferential treatment. This indicates that there is ease of market access for the top 5 imports sourced from each other and this could promote increased intra-regional trade among member states in these product categories because tariff and non-tariff barriers to trade will be progressively eliminated once the TFTA is in place.
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  • Date Issued: 2020

The current role of palm species Hyphaene Coriacea and Phoenix Reclanata in local livelihoods in the Zitundo area, southern Mozambique

  • Authors: Martins, Angelina R O
  • Date: 2020
  • Subjects: Ilala palm -- Economic aspects -- Mozambique , Palms -- Economic aspects -- Mozambique , Non-timber forest products industry -- Mozambique , Sustainable development -- Mozambique , Conservation of natural resources -- Mozambique
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/150613 , vital:38989
  • Description: The majority of rural households in developing countries are heavily dependent on non-timber forest products (NTFPs) to fulfill much of their basic daily needs. In Mozambique more than 64% of the population lives in rural areas and depends heavily in the extraction of NTFPs to complement agricultural production. One substantial source of NTFPs are palm species. Palms are sources of food, building materials, cloth, ornaments, medicines, and are also used for cultural purposes. In southern Mozambique two important palms species used as NTFPs are Hyphaene coriacea and Phoenix reclinata. These two species provide an array of subsistence and commercial products. The sap, leaves and stems of these two palms are harvested by local people as sources of traditional beverages, weaving, roofing, fencing and furniture material as well as other household utensils. The effects (if any) of harvesting of these palm products on palm distribution, population structure, dynamics and viability have never been examined, and thus the sustainability of the practices and benefits flows to local livelihoods are unknow-n. Any effects harvesting effects may also be exacerbated by predicted climate change for the area. The present study aims to investigate the role of the palm species Hyphaene coriacea and Phoenix reclinata in the livelihoods of households in the Zitundo area, Matutuine district, southern Mozambique and under future climate scenarios. Specifically, this study: i) evaluates the abundance, population structure and harvesting selection of these species; ii) characterizes the ethnobotanical knowledge and use of the two species; iii) examines the local production and trade of palm wine in the area; iv) examines the contribution of palm income to livelihoods and income diversification in area; v) describes the local management practices and perceptions on palm productivity and abundance; and vi) models the current and future distribution of the these palm species in the area. To evaluate the abundance, population structure and stability of these two palm species a population census was carried out, and the size class distribution, Simpson index of dominance, permutation index and the quotient between successive size classes were calculated. I further calculated the preference ratio for specific size classes. Additionally a questionnaire survey was conducted with 179 randomly selected households from the 16 villages in the study area to characterize the ethnobotanical knowledge and use of these two species, as well as to examine the contribution of palm income to livelihoods and diversification. Standard ethnobotanical indices were used as measures of each palm species use and knowledge while principal component analysis and cluster analysis were applied to highlight the livelihood patterns and the role of diversification and of palm income in local livelihoods. Structured interviews with 37 palm tappers were additionally used to examine the local production and trade of palm wine in the area, while both the household survey and palm tappers interviews, were employed to investigate the local management practices and perceptions on palms productivity and abundance. Maxent Software was used to model the current and future under climate change distribution of the two palm species. Hyphaene coriacea was more abundant than Phoenix reclinata. Both species exhibited steep negative slopes in the regression analyses of size class distribution, indicating the presence of more individuals in shorter size classes. Although there was a dominance of shorter over taller size classes, limited recruitment was observed through low stem densities of seedlings and juveniles compared to the 1-50 cm size class The Simpson index of dominance, the permutation index, and the fluctuating quotients between the consecutive size classes showed a level of instability in both populations. Hyphaene coriacea appeared to be more resilient to tapping than Phoenix reclinata as showed by the higher rate of stem survival after tapping. Hyphaene coriacea was favored for tapping compared to Phoenix reclinata. The most preferred size class to tap for both species was between 101cm and 150 cm. Currently the distribution of Hyphaene coriacea and Phoenix reclinata was mostly confined to the eastern side of the study area. Most of the area was predicted as unsuitable for both palm species, with less than six percent predicted to be suitable or higher. The occurrence of both species appeared to be influenced mostly by water related variables, such as precipitation, and distance to rivers and distance to water bodies. The habitat suitability for Hyphaene coriacea was predicted to increase under future climate conditions scenarios, while little variation was predicted for Phoenix reclinata distribution. The knowledge about the uses of these two palm species was widespread in the area, although only 32% of respondents were engaged in palm exploitation. Thirteen palm products were exploited, with palm wine production from the sap of both palms being the dominant activity, followed by broom production from Phoenix reclinata stems and basket production from Hyphaene coriacea leaves. The cultural importance of these species included the production of anklets and skirts used during traditional dances and the use of palm wine in the traditional ritual of libation. Palm tapping was practiced year round in five of the sixteen villages in the area. Palm tapping was an important livelihood activity, contributing over 80% of tappers’ total annual income, and tappers earned up to three times more than the national minimum wage for the agricultural and forestry sector. Palm wine was also a highly commercial commodity in Zitundo area, with an average commercialization index above 60%. The income from palm wine sales showed an important role in mitigating the level of poverty in the area. Palm income accounted for over 60% reduction on poverty incidence among palm tappers. Households in Zitundo further engaged in some level of livelihood diversification. The majority of households adopted a wage-based strategy, although this strategy was among the less remunerative in terms of per capita cash income. A palm-based livelihood strategy, although adopted only by 11% of households, was one of the most remunerative strategies. Palm income played a vital role in enhancing household livelihoods and mitigating poverty in the area as shown by the lower poverty incidences among households engaged in the palm-based livelihood strategy than alternatives strategies. The village of household residency, along with household demographic and socio-economic characteristics appeared to determine the knowledge and exploitation level of palms as well as a households’ choice of livelihood strategy, level of palm wine returns, commercialization index and palm income dependency. The importance of palms in local livelihoods and poverty alleviation needs greater acknowledgement by government and development agencies in the area. Palm wine, broom and basket production have a high potential for income generation, and therefore should be included in future local development policies and poverty reduction strategies. Although palms are an open access resource in Zitundo area, the perception is that they are abundant and that tapping does not have many detrimental effects. However, this study found some negative impacts of tapping on the recruitment of both palms species. The inclusion of palm products in future development programs and poverty reduction strategies will require the design of participatory conservation and management strategies that involve all palm users groups and others stakeholders and include long-term participatory monitoring of the effect of palm use on the populations.
  • Full Text:
  • Date Issued: 2020
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