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Efficient market hypothesis with structural breaks: evidence from BRICS stock markets

  • Authors: Guduza, Sinazo
  • Date: 2019
  • Subjects: Stock exchanges , Investment analysis Developing countries -- Economic conditions
  • Language: English
  • Type: Thesis , Masters , MCom
  • Identifier: http://hdl.handle.net/10948/42342 , vital:36647
  • Description: The study is an examination of weak form market efficiency (EMH) in BRICS equity markets using weekly data spanning from 2005 to 2018. The study makes use linear as well as nonlinear unit rot tests, that is, the ADF and KSS tests respectively. For more robust results, the study uses the Integer Flexible Fourier Function (IFFF) and the Fractional Frequency Flexible Fourier Function (FFFFF) to account for smooth structural breaks. The study investigates the full sample period and splits the empirical data into three sub-samples corresponding to the period succeeding the global financial crisis, the BRICS summits and the BRICS Development Bank (BDB). This study, to the best of our knowledge, is the first to investigate the efficiency in the BRICS stock markets using a combination of the specified series of unit root tests. Moreover, there are no prior studies that have examined these markets for the sub-samples mentioned above. Our empirical results point us to convincing evidence of weak form inefficiency as the majority of the results reject the null hypothesis of a unit root.
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  • Date Issued: 2019

Eight decades of invasion by Chromolaena odorata (Asteraceae) and its biological control in West Africa: the story so far

  • Authors: Aigbedion-Atalor, Pascal O , Adom, Medetissi , Day, Michael D , Uyi, Osariyekemwen O , Egbon, Ikponmwosa N , Idemudia, I , Igbinosa, Igho B , Paterson, Iain D , Braimah, Haruna , Wilson, David D , Zachariades, Costas
  • Date: 2019
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/417450 , vital:71454 , xlink:href="https://doi.org/10.1080/09583157.2019.1670782"
  • Description: Chromolaena odorata (L.) R.M. King and H. Robinson (Asteraceae) is a perennial weedy shrub of neotropical origin and a serious biotic threat in its invasive range. The Asian-West Africa (AWA) biotype of C. odorata present in West Africa is both morphologically and genetically different from the southern African (SA) biotype. The AWA biotype was first introduced into Nigeria in the late 1930s and rapidly spread across West Africa. Currently, 12 of the 16 countries in West Africa have been invaded, with significant negative effects on indigenous flora and fauna. However, locals in West Africa have found several uses for the weed. As chemical, physical and other conventional methods were unsustainable, costly and largely ineffective, three biological control agents, Apion brunneonigrum (Coleoptera: Brentidae), Pareuchaetes pseudoinsulata (Lepidoptera: Erebidae) and Cecidochares connexa (Diptera: Tephritidae), have been released in West Africa between the 1970s and the early 2000s. However, only C. connexa and P. pseudoinsulata established, contributing to the control of the weed, in six and four countries in West Africa respectively. Limited research funding, the absence of post-release evaluations of the established agents, and the ‘conflict of interest’ status of C. odorata (i.e. being beneficial for local use but damaging to ecosystem services and agriculture), are serious factors deterring the overall biological control effort. Here, using historical records and field surveys, we examine the invasion history, spread, impacts, and management of C. odorata in West Africa and make recommendations for the sustainable management of C. odorata in the region.
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  • Date Issued: 2019

Ekhakhamela

  • Authors: Machi, Nolwazi Fortunate
  • Date: 2019
  • Subjects: Xhosa poetry
  • Language: English
  • Type: text , Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/76332 , vital:30549
  • Description: My collection of isiZulu poems is based on my rural and traditional upbringing. It draws on language and customs which have shaped and defined me as a woman born in the South of KwaZulu-Natal. I write about how I have to conform to both a rural life and an urban one that forms my second world. I find myself having to switch between these lives, which benefits me a lot, and I feel a responsibility to bring hope to young people especially from the rural side, that nothing is wrong with being who and where they are. My writing is influenced by authors such as Nazim Hikmet, Mafika Gwala, and Mazisi Kunene who encourages black writers to write about their own customs and stories rather than embracing ‘western civilization’ and foreign languages. I also like the contemporary subjects and the humour in Dr Nakanjani Sibiya’s work.
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  • Date Issued: 2019

Elasticity of the South African economy towards portfolio investments in BRICS countries

  • Authors: Taonezvi, Lovemore
  • Date: 2019
  • Subjects: Economic development -- South Africa
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10948/44537 , vital:38141
  • Description: The emerging economies of Brazil, Russia, India, and China (BRIC) have been experiencing high growth rates since the turn of the millennium, whereas economic growth has been elusive in South Africa. As the newest member of BRICS, South Africa is expected to economically benefit through, amongst others, increases in capital flows, foreign investments by local firms, and increases in trade. Such benefits are anticipated to propel the country’s economic growth, thereby helping it to tackle its chronic problems of high unemployment, poverty, and economic inequality. The inclusion of South Africa in BRICS has, however, been viewed by critics as erroneous, since the country has, inter alia, poor economic growth; a small economy and population; and political instability. While foreign portfolio investment (FPI) inflows to South Africa have surged in recent years, economic growth has remained lacklustre. These flows have also faced sudden reversals, especially during the financial crisis of 2007-2009. With the potential to leverage its growth from intra-BRICS FPI inflows, it becomes of paramount significance for policymakers to have knowledge of the South African economy’s responsiveness to such inflows. With a theoretical framework based on the endogenous growth model, an augmented Cobb-Douglas production function was extended in this thesis in order to study the relationship between BRICS growth and intra-BRICS FPI in a dynamic panel data generalised method of moments (GMM) context. Similarly, the South African economy’s elasticity towards intraBRICS FPI was estimated. Vector autoregressive (VAR) analysis was used to evaluate the responsiveness of South Africa’s economy to an innovative shock to intra-BRICS FPI. Annual and quarterly data for the period 2000-2016 were used in panel data and VAR analysis, respectively. It was found that intra-BRICS FPI flows have a positive and statistically significant relationship with BRICS growth, while the elasticity of the South African economy to these flows is estimated at 0.007. Additionally, the efficiency and accessibility dimensions of financial market development do not assist FPI in promoting growth in BRICS, while financial market depth does. South Africa’s BRICS membership has a positive effect on its own growth, while for other BRICS nations, this membership is negative and insignificant. Credit rating downgrades have a negative and insignificant impact on economic growth, while the negative impact for inflation, government expenditure, and total labour employment is significant. Conversely, gross capital formation and trade openness have a positive and significant relationship with BRICS growth. The study also determined that a unit shock on intra-BRICS FPI resulted in negative fluctuations of South Africa’s economy within the first eight quarters before being positive and mostly constant thereafter. By supplementing domestic savings and facilitating the international integration of domestic financial markets, FPI promotes growth in BRICS. The short-term, ease of reversibility, and speculative nature of FPI are amongst some of the reasons for its destabilising effect on South Africa’s economy. Furthermore, inflation is a key determinant of FPI inflows to South Africa. Additional BRIC cooperation in FPI and trade; increased investments in domestic capital; reductions of inflation and corruption; investments in education and skills development; and stock market reforms are some of the recommendations for BRIC, and South Africa in particular. South Africa can consider prudential use of a mix of capital account controls, as well as fiscal and monetary policies to cushion its economy from FPI shocks in the short- to medium-term.
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  • Date Issued: 2019

Elections as Drivers of Political Instability in Africa: A Case Study of Lesotho

  • Authors: Moorosi, Mantsoaki
  • Date: 2019
  • Subjects: Elections Political parties -- Lesotho
  • Language: English
  • Type: Thesis , Masters , MSoc (Political Science)
  • Identifier: http://hdl.handle.net/10353/16462 , vital:40722
  • Description: The study sets out to investigate elections as drivers to political instability in Africa, using Lesotho as a case study from 2012 to 2017. It employs primary and secondary sources of data. The period is of interest for two reasons. Firstly, the continuing instability post three successive free and fair elections, and secondly, the advent of Coalition Governments. The structure adheres to two theoretical frameworks namely, a) Huntington’s two turn-over test and, b) Karl’s Fallacy of Electoralism. In order to investigate how elections could or could not be drivers to political instability, the researcher looked at the different forms of political instability in Lesotho. These include attempted coup d’état, assassinations and violation of territorial sovereignty. The later form being peculiar to the period under study as the other forms had occurred at some stage through the political history of this country. It further asserts uncertainty of hung Parliament and politicised institutions as attributes to the recurrence of political instability. It concludes that Lesotho is a deviant case from the two turn over test. The scope of the study supports the fallacy of electoralism. Several recommendations have been presented. These include that Government of Lesotho should amend the Constitution on the functions and powers of the King, Politicians should implement the promises they made to the electorates during campaigns, and regulate or abolish floor crossing in Parliament amongst others.
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  • Date Issued: 2019

Electric cars: their carbon implications and adoption in South Africa

  • Authors: Moeletsi, Mokhele Edmond
  • Date: 2019
  • Subjects: Electric vehicles -- Economic aspects , Electric vehicles -- South Africa Power resources -- South Africa Sustainable development -- South Africa Energy policy -- South Africa
  • Language: English
  • Type: Thesis , Masters , MBA
  • Identifier: http://hdl.handle.net/10948/41886 , vital:36606
  • Description: Climate change is a reality that is starting to have an impact on society through decreased agricultural production and increased extreme weather events, resulting to worldwide disasters. It is caused by human activities that release greenhouse gas emissions into the atmosphere. One of the key areas of concern is the mobility sector which accounts for around 20% of the total energy use, with a GHG footprint of close to 14% of the global emissions. International organisations are concerned about the elevating GHG emissions resulting from the increasing internal combustion engine vehicles, leading to the recent wave in electrifying the vehicles which presents many of advantages as well as major constraints. This study used the quantitative research approach to investigate the possible benefits of electric vehicles to our environment in the future. The projections of vehicle population size were estimated using three cases, and the electric vehicle penetration into the market by 2030 was investigated with four different scenarios. Further research was done to investigate the possible barriers present in the South African market that impede the adoption of electric vehicles. The results showed that the projection of the business-as-usual case, coupled with mitigation scenarios, present a better option for mitigation. The worst case of exponential increases in vehicle population does not present any GHG emissions moderation hope for any of the mitigation scenarios used in the study. The other case shows high mitigation potential, but it leads to a case of economic decline where the numbers of vehicles are decreasing with time. The findings of the study on barriers to adoption of electric vehicles in the market highlighted the high purchase price, high battery price and high likelihood for owning a secondary vehicle based on the current circumstances, as the main barriers that the respondents in the Gauteng Province found to be unattractive. But generally the willingness to buy electric vehicles was high for the majority of the factors that were presented. With these perceived positive opinions by the respondents, it is down to government and private companies to provide an environment conducive to changed opinions conducive for the consumers. This relates to advancing the technology and providing policy support for the accelerated adoption of electric vehicles.
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  • Date Issued: 2019

Electrical, photo-thermal and mechanical degradation analysis of degraded single junction amorphous silicon solar modules

  • Authors: Osayemwenre, Gilbert Omorodion
  • Date: 2019
  • Subjects: Solar cells Amorphous semiconductors Silicon
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10353/15211 , vital:40204
  • Description: In this present era of sustainable energy development, photovoltaic modules which are based on amorphous silicon cells have immeasurable prospects of contributing meaningfully to the energy demand of the world at large. The global consciousness of environmental safety issues has birthed the rapid demand for the photovoltaic system. However, the production increase is mainly in bulk-type crystalline (c-Si) solar cells. Thus, to meet the high demand of the market, single junction amorphous silicon (a-Si:H) solar cells production must be encouraged through active research in that regard. This could also help to improve its efficiency and reliability. There has recently been a sharp decrease in the production cost of the bulk Si solar cell, but the a-Si:H solar cell still remains the most economically viable in comparison to the other PV technologies. Companies such as Sharp are currently developing large-scale a-Si:H solar modules that can produce an efficiency of 10.5% after the long-term degradation process. To date, a-Si:H is believed to be one of the most promising thin-film PV technologies (Saito et al., 1993; Hamakawa et al., 1994). The cost of a solar PV manufacturing fell by 6% in 2014 (Santa, 2014), this is in accordance with the 2008 cost production forecast; thus, the cost record stands at 0.20 per watt, as reported by the NPD Solar publisher. Amorphous silicon (a-Si) solar modules generate more kilowatt-hour (kWh) of electricity per kilowatt (kW) than crystalline silicon or other technologies of the same capacity of installation. Furthermore, a-Si:H modules have more functional hours per day. Single junction amorphous silicon (a-Si:H) modules can function beyond the peak sun hours, and they also have a better performance on a cloudy day. vii In other words, a 1kW PV system of a-Si:H is expected to generate more electricity per year in comparison to 1kW PV from other technologies, hence there is a low energy payback time. In this study, commercially available single junction amorphous silicon modules were bought from a local market and they were immediately deployed outdoors. The initial reading of the modules, which served as baseline reading, showed an average of 25% decrease in the modules performance, therefore, there is a need for a long term monitoring process to obtain the best and worst performing modules. Measuring the performance parameters of these PV modules under real sun light (IV) provides a better degradation assessment. This conventional assessment cannot provide an in-depth insight responsible for the variation and degradation of the performance parameters. More obscured parameters like recombination current and ideality factor were obtained from the dark IV measurements. However, this is still superficial in a way. The intrinsic parameters were obtained from scanning probe microscopy (SPM) and CV measurements. The study focuses on the degradation analysis of a-Si:H due to an increase in defect density. A rise in the defect concentration is a huge problem because it causes long-term solar cell degradation, which increases the recombination current and decreases the conversion efficiency. Furthermore, it decreases the photo-generating current and reduces the effective efficiency of the solar device. In other words, the electrical output decreases. This research investigates the reduction in a-Si:H modules’ maximum power, and correlates these with a hot spot formation. A PVPM IV tracer was used for the outdoor characterisation of the module’s temperature profile, while the IR camera was used to analyse the hot spot centre. A four probe IV/CV from NMU was used for the indoor assessment of smaller samples cleaved from both the affected and non-affected regions to characterise the electrical variations across the module viii samples. To be precise, in this study, a naturally degraded single junction amorphous silicon module was delaminated and its mechanical properties were analysed and correlated with the contact potential from a Kelvin probe force microscopy (KPFM).
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  • Date Issued: 2019

Electrocatalytic activity of a push pull Co (II) phthalocyanine in the presence of graphitic carbon nitride quantum dots

  • Authors: Nxele, Siphesihle R , Oluwole, David O , Nyokong, Tebello
  • Date: 2019
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/186746 , vital:44530 , xlink:href="https://doi.org/10.1016/j.electacta.2019.134978"
  • Description: This work reports for the first time on the use of a conjugate of graphitic carbon nitride quantum dots (gCNQDs) with a push-pull asymmetrical cobalt phthalocyanine (CoPc) for electrochemical sensing. The nanocomposite is immobilized on a glassy carbon electrode (GCE) surface for the use in l-cysteine electrocatalysis. The nanocomposites were characterized using techniques such as X-ray diffractometry (XRD), Fourier transform infrared (FTIR) spectroscopy, UV-vis spectroscopy, transmission electron microscopy (TEM), energy dispersive X-ray (EDX) analysis, Raman spectroscopy and electrochemical methods. The nanocomposites were immobilized by the drop-dry method, sequentially or when premixed in solution. Good electrocatalytic oxidation of l-cysteine was observed, especially by the sequentially modified electrode surface, with the CoPc on top of gCNQDs. The sensitivity was determined as 3.5 μA.mM-1 and the limit of detection (LoD) as 101.3 μM for GCE-gCNQDs, 0.65 μA.mM-1 and 0.96 μM for GCE-CoPc, 23.41 μA.mM-1 and 0.41 μM for gCNQDs-CoPc (premixed) and 100.5 μA.mM-1 and 0.02 μM for gCNQDs-CoPc (sequential). The electrode surfaces also showed high stability by continuous cyclization.
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  • Date Issued: 2019

Electrocatalytic Activity of Asymmetrical Cobalt Phthalocyanines in the Presence of N Doped Graphene Quantum Dots: The Push-pull Effects of Substituents

  • Authors: Nkhahle, Reitumetse , Sekhosana, Kutloano E , Centane, Sixolile , Nyokong, Tebello
  • Date: 2019
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/186904 , vital:44546 , xlink:href="https://doi.org/10.1002/elan.201800837"
  • Description: A series of Co phthalocyanine (CoPc) derivatives and their respective nitrogen doped graphene quantum dot conjugates were used as catalysts towards the electrooxidation of hydrazine. Using a glassy carbon electrode as a support for the electrocatalysts, through cyclic voltammetry and chronoamperometry, the effects of combining the CoPcs with the nitrogen doped graphene quantum dots (NGQDs) were studied. The general observations made were that the NGQDs improve the catalytic activity of the CoPcs in both the p-p stacked and covalently linked conjugates by increasing the sensitivities and lowering the limits of detection with values as low as 0.43 mM being recorded.
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  • Date Issued: 2019

Electrocatalytic activity of ethynylbenzyl phthalocyanines when linked to quantum dots via click chemistry: Towards efficient oxygen reduction reaction and H2O2 oxidation

  • Authors: Mpeta, Lekhetho S , Nyokong, Tebello
  • Date: 2019
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/187037 , vital:44558 , xlink:href="https://doi.org/10.1016/j.jelechem.2019.03.064"
  • Description: This work describes the conjugation of Co, Mn and Fe tetra ethynyl benzyl phthalocyanines to CdTe/ZnS quantum dots via click chemistry. The synthesized conjugates were then immobilised on glassy carbon electrode and their electrocatalytic activity towards hydrogen peroxide oxidation and oxygen reduction investigated. CoPc (1)-QDs showed superior electrocatalytic behaviour towards hydrogen peroxide catalysis with sensitivity of 2.8 × 105 μA/mM and limit of detection of 0.023 μM. On the other hand, FePc(3)-QDs showed the best oxygen reduction activity involving a direct 4-electron mechanism.
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  • Date Issued: 2019

Elucidating the Molecular Basis of the Interaction between the β2-integrin, αXβ2, and the low-affinity IgE Receptor, CD23

  • Authors: Clarke, Stephen
  • Date: 2019
  • Subjects: CD23 antigen , Immune response Cellular immunity Molecular immunology
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10948/37990 , vital:34277
  • Description: The low affinity IgE receptor, CD23, is involved in a myriad of immune reactions. It is not only a receptor for IgE, but also functions in the regulation of IgE synthesis, isotype switching in B cells, and induction of the inflammatory response. These effector functions of CD23 arise through its interaction with another leukocyte-specific cell surface receptor – the β2 integrin subfamily. However, this interaction has not been fully described. It has been shown that CD23 is capable of interacting with the β3 and β5 integrin β-subunit of integrins via a basic RKC motif in a metal cation-independent fashion. The currently proposed mechanism for the interaction between CD23 and the integrin superfamily was applied to the β2 integrin subfamily. In this study the interaction was probed for whether or not the RKC motif governs the interaction as well. This was done by performing bioinformatics docking predictions between the CD23 and αXβ2 integrin proteins. This revealed that in the absence of cations, the RKC motif is involved in interaction with the integrin αI domain. However, since physiologically integrin activity has been shown to be regulated by metal cations, docking predictions were also performed in the presence of such cations. This showed the interaction to involve novel acidic motifs within the CD23 protein, GEF and LDL. This same pattern of interaction was seen in docking predictions between CD23 and the β2- and β3I-like domains. To further investigate, recombinant proteins of sCD23 and the αXI domain were produced using E. coli expression systems. The DNA sequence was mutated to produce mutant versions of the CD23 RKC and GEF motifs as well as a high-affinity locked αXI domain. These proteins were used in subsequent SPR spectroscopy analysis of the binding affinity between immobilised integrin and CD23 analyte. It was shown that the mutation within the RKC motif reduced the binding affinity under cation-independence, especially when the Arg172 residue was substituted. However binding was not completely lost. This result was supported by synthetic peptides containing the same RKC motif and substitutions. These showed complete loss in binding in the double RKΔAA substitution, suggesting the involvement of other residues in the RKC-dependent interaction. In contrast, under cation dependence, the RKC motif substitutions showed no effect on binding affinity, while the GEF motif substitution exhibited near complete loss in binding. This same effect on binding was validated by U937 cell-based ELISA using live cells. This showed decreased capture of differentiated U937 cells, expressing the αXβ2 integrin, by immobilised recombinant sCD23 protein. In this study it was noted that, 2 contrary to the SPR analysis, metal cations allowed for a higher titre of cells to be captured in comparison to the cation-free binding.
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  • Date Issued: 2019

Empire in Lusaka: hip-hop, young men and masculinity in an African city

  • Authors: Mulolani, Happy
  • Date: 2019
  • Subjects: Empire (Television program : 2015) -- Influence , Hip-hop -- Zambia -- Lusaka , Young men -- Zambia -- Lusaka , Young men -- Psychology -- Zambia -- Lusaka , Young men -- Social conditions -- Zambia -- Lusaka , Rap musicians -- Zambia -- Lusaka , Masculinity -- Zambia -- Lusaka
  • Language: English
  • Type: text , Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/92650 , vital:30736
  • Description: This study examines young Zambian men who are aspiring hip hop artists in Lusaka and the meanings they make of the representations of masculinity in Empire, a popular US television drama. Broadcast locally via satellite on the South African cable network, DStv, Empire narrates the story of a family of powerful men as they battle for the control of Empire, a successful hip-hop label. Of significance is how the programme’s representations of masculinity resonate with the young men’s own ideas of masculinity within a highly patriarchal and conservative urban African space. The young male hip-hop artists encounter their everyday experiences in a context of a range of socio-economic challenges within the urban space of Lusaka which presents them with very limited economic opportunities and resources. Underpinned by a constructivist approach, this reception study explores how these young male artists encounter their everyday experiences in the city and how its structural constraints are navigated through hip-hop, a highly popular local cultural form. The male artists’ reactions to the programme are dependent on their socio-economic location and the types of skills and resources they draw on in order to traverse their everyday experience of city life which concurrently is perceived as exclusionary and as impacting on their livelihoods and aspirations.
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  • Date Issued: 2019

Employee happiness at ARMSCOR

  • Authors: Rakgabyane, Michael Tsie
  • Date: 2019
  • Subjects: Employee morale
  • Language: English
  • Type: Thesis , Masters , MBA
  • Identifier: http://hdl.handle.net/10948/43018 , vital:36732
  • Description: The subject of happiness has captured many across the world. There is an increasing debate on whether there is a link between improving the national happiness levels and country’s Gross Domestic Product (GDP). Happiness has become an area of interest for both organisations and individuals because of the consequential benefits. Research affirmed the importance of happiness in improving the function of both society and organisations. The benefit thereof includes but is not limited to increased productivity and longevity. Having unhappy employees could have dire effects on the organisations due to the direct impact on the organisation’s financial and social conditions. The arms industry is generally seen as a highly secretive industry due to the strategic position and importance that it occupies in various countries. Happiness in the arms industry has never been explored. This makes this study new in this particular industry. The arms industry as a whole can also benefit by focusing on improving employees’ happiness levels. This makes the study in Armscor important as it would help to provide some insight on the happiness levels in this industry. The focus of this study is to establish happiness levels of Armscor employees. For the purpose of this study, the primary data for the study were collected from a representative sample of 170 Armscor employees which included 161 permanent and 9 non-permanent employees. The questionnaire designed from the literature was used to collect the data. The in-depth literature review that was conducted in carrying out this study included exploring the different perspectives from which happiness is defined. This included three seemingly dominant perspectives: philosophic, economic and psychological perspectives. Furthermore, the review of literature included examining happiness theories and explored three main theories: Comparison, Folklore and Livability. The literature review provided a basis for a proposed conceptual model, which suggested the following factors as influencing happiness in the workplace: workplace influence, workplace relationships, work-life balance, purpose, optimism, work satisfaction, leisure, SA pride and trust. Exploratory factor analysis was used to test the proposed conceptual model and the results indicate that workplace influence, workplace vi relationships and work satisfaction load onto the factor work; while trust and SA pride load onto the factor trust pride; and purpose, work-life balance and optimism load onto the factor purpose work-life optimism. The treatise concludes with recommendations that management can consider implementing to improve the happiness levels of employees at Armscor. This study contributes to understanding the happiness levels of employees in the arms industry.
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  • Date Issued: 2019

Employee talent management in the Uganda health sector: a public institutions perspective

  • Authors: Nakato, Jamidah
  • Date: 2019
  • Subjects: Employee retention -- Uganda , Leadership -- Uganda Executives -- Training of Executive ability
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10948/41751 , vital:36578
  • Description: Globally, talent management has been acknowledged as a prime source of employee attraction and retention as well as organisational performance and commitment. Although the health sector plays an important role in the economic development of any country, in Uganda, the management of talented employees still remains a challenge. In this country, many institutions have not incorporated and adopted suitable talent management strategies, thus compromising access to and quality of care. A hypothetical model and measuring instruments were developed to investigate the factors contributing to and the benefits of effective employee talent management in the Ugandan health sector. The following ten independent variables that have the prospect of influencing effective talent management (intervening variable) were identified on the basis of organisational, management and personal factors: talent pool, organisational support, work conditions, social and work environment, reward system, leadership styles, career development, supervisor support, employee engagement and employee personality. In this study, it was also postulated that talent management has potential to effect the dependent variables, namely, talent attraction, employee retention, organisational performance and organisational commitment. In total, fourteen hypotheses were formulated to test relationships between independent, intervening and dependent variables. The study utilised the quantitative research paradigm in order to seek employee perceptions regarding public institutions within the health sector, in Uganda’s Central region. Using stratified random sampling, a sample of 910 participants was drawn from the identified population. A survey was conducted with the aid of a structured, selfadministered questionnaire that was distributed to the seven categories of hospitals and health centres in Central Uganda; 910 questionnaires were distributed to doctors, consultants, dentists, dispensers, nurses, pharmacists, clinical officers, laboratory staff, occupational therapists, allied health staff, environmental health officers, general administrative cadres, cold chain technicians and support staff. Of these, 655 were useable, which indicates a 71% response rate. The data collected was captured and analysed using various statistical analysis techniques. The study findings reveal that organisational support, employee satisfaction, an enabling work environment, a stable working environment and career development effectively influence talent management. However, management in health sector institutions need to realise the importance of facilitating and monitoring job autonomy and personal values in order to effectively enhance talent management. The study results further reveal that talent management has a positive influence on employee retention and holistic development for organisational performance. For optimal talent management, the study recommends that organisations pay attention to cultivating an enabling and stable work environment that is suitable for motivating employees towards improved performance and work commitment. Therefore, health sector management should focus on potential, and not only on performance, by matching individuals with the right positions that can expose their capabilities and potential. It was further recommended that organisations need to accept and show confidence in their employees by allowing them freedom in carrying out their tasks. In addition, it was highlighted that ascertaining and utilising information about the values and principles that employees hold can help explain their behaviours and attitudes at work. This would increase the chances of talented employees realising their full potential and competencies in their jobs. Therefore, this study found that there is a need for public institutions within the health sector to focus on supporting employees by offering a well-defined career development programme, which caters for the needs of individuals and which acts as an incentive for the recruitment of qualified employees. Thus, management will succeed in retaining, attracting and maintaining talented individuals who can perform well. In order to uphold the expected ethical behaviour of conducting research, the researcher obtained approval and ethics clearance from Nelson Mandela University, permission to conduct the study from the Ugandan Ministry of Health, and communicated all the information relevant to the study to the participants.
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  • Date Issued: 2019

Employing the Processing Capability of Mixing Consoles and Audio Interfaces to Spatialize Sound:

  • Authors: Foss, Richard
  • Date: 2019
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/426758 , vital:72389 , https://www.aes.org/e-lib/browse.cfm?elib=22211
  • Description: Many audio interfaces and all mixing consoles have signal mixing capabilities. This paper describes an immersive sound system that employs these capabilities in order to spatialise sound sources, where these sources could be any of the inputs to these mix-capable devices. Graphic spatialisation control is provided on client devices, and 3D coordinates are sent to a server. The server uses these coordinates and speaker positions to render mix level and reverb parameter values. These values are sent to the mixer device using a control protocol. Advantages of this approach are that all inputs can be spatialised, and low-level processing is offloaded from the computer.
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  • Date Issued: 2019

Encapsulation of isoniazid-conjugated phthalocyanine-In-cyclodextrin-in-liposomes using heating method

  • Authors: Nkanga, Christian I , Krause, Rui W M
  • Date: 2019
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/193999 , vital:45414 , xlink:href="https://doi.org/10.1038/s41598-019-47991-y"
  • Description: Liposomes are reputed colloidal vehicles that hold the promise for targeted delivery of anti-tubercular drugs (ATBDs) to alveolar macrophages that host Mycobacterium tuberculosis. However, the costly status of liposome technology, particularly due to the use of special manufacture equipment and expensive lipid materials, may preclude wider developments of therapeutic liposomes. In this study, we report efficient encapsulation of a complex system, consisting of isoniazid-hydrazone-phthalocyanine conjugate (Pc-INH) in gamma-cyclodextrin (γ-CD), in liposomes using crude soybean lecithin by means of a simple organic solvent-free method, heating method (HM). Inclusion complexation was performed in solution and solid-state, and evaluated using UV-Vis, magnetic circular dichroism, 1H NMR, diffusion ordered spectroscopy and FT-IR. The HM-liposomes afforded good encapsulation efficiency (71%) for such a large Pc-INH/γ-CD complex (PCD) system. The stability and properties of the PCD-HM-liposomes look encouraging; with particle size 240 nm and Zeta potential −57 mV that remained unchanged upon storage at 4 °C for 5 weeks. The release study performed in different pH media revealed controlled release profiles that went up to 100% at pH 4.4, from about 40% at pH 7.4. This makes PCD-liposomes a promising system for site-specific ATBD delivery, and a good example of simple liposomal encapsulation of large hydrophobic compounds.
  • Full Text:
  • Date Issued: 2019

Energy yield modelling and analysis of photovoltaic systems in Namibia

  • Authors: Dobreva, Petja
  • Date: 2019
  • Subjects: Photovoltaic power systems , Photovoltaic power generation Photovoltaic power generation -- Mathematical models
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10948/39523 , vital:35287
  • Description: Generation of electricity from solar energy by photovoltaic systems has the potential to reduce dependence on non-renewable sources for electrical energy production. It can also reduce the cost of electricity for consumers by moving away from the traditional models of centralised generation combined with extensive transmission. The prices of photovoltaic system components have decreased so dramatically in recent years that nowadays a large portion of the cost of electricity produced by photovoltaic systems is due to the cost of investment capital rather than the cost of the physical parts of the system. The cost of capital is determined by the perceived risk of the investment and is contingent on predictive models whose aim is to project outputs reasonably achievable by the system. The output of a photovoltaic system depends strongly on external factors, like solar radiation and temperature, as well as internal, system specific factors. Models that can accurately predict the output of a photovoltaic system have direct impact on investment cost. Several measures, like root-mean-square-error or coincident of determination, have been used in the past to assess accuracy of models but they appear to be inadequate for the task. I suggest a new method, comprising qualitative and quantitative measures, for model evaluation and introduce two new quantities to assess the predictive capabilities of the models. Models of several photovoltaic systems in Namibia were created, the new evaluation approach was applied to them and the results were compared to the conclusions that would have been drawn if the old measures were used. Outdoor current-voltage measurements are used to assess the power output and general state of the solar generator of a photovoltaic system, but the measured values strongly depend on irradiance and temperature. The prevailing approach has been to transform the current-voltage characteristics to standard-test-conditions with the so-called translation equations and then compare the translated power to the nominal value. The translated value of the power, however, depends on the translation equations used and is not necessarily an accurate reaction of the state of the solar generator. I have proposed a new method for assessment of the state of the solar generator that relies only on the measured quantities and does not require translations to standard-test-conditions. This alternative method has been used in the assessment of the condition of the solar generators in the systems included in this study.
  • Full Text:
  • Date Issued: 2019

Engagement in local social-ecological knowledge practices in a seasonal cycles approach for transitioning to future sustainability

  • Authors: O'Donoghue, Rob B
  • Date: 2019
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/387971 , vital:68294 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/186419"
  • Description: This paper explores climate as variable natural forces driving seasonal cycles1 that many African cultures had adjusted themselves to within intergenerational knowledge practices of longue durée. The study points to the need to re-orientate and expand climate science education so that it is centred on the seasonal cycles and intergenerational learning to better align transitioning to future sustainability with these in our southern African contexts of climate change today. The narrative touches upon historical accounts of knowledge practices amongst the Krobo, Bemba, Shona, Zulu and Xhosa, briefly pointing to how each, as an African culture, is situated as a social-ecological entity within the climatic tapestries of our African landscapes. It takes note of how cultural articulation within the seasonal cycles of regional climate have a long history with adaptive change in some contexts in more recent times. The review suggests that our learning in relation to emerging climate change should be informed by these histories of intergenerational knowledge practice. It notes how a better grasp of these could be important drivers of a widening cultural response to the changing dynamics in our climatic surroundings today. The brief study suggests that southern Africa is a special place with many unique and interesting climatic processes and associated socio-ecological systems and practices. These can provide engaging perspectives for informing education to mitigate or adapt to climate change. Here, a situated exploration of seasonal cycles can draw on both the latest in modern climate science and the rich social-ecological heritage of Africa briefly touched upon in the study. A model of process is offered for how both can be used in a seasonal cycles approach climate change education. This better situated and more inclusive approach can enable us to contemplate how we might best adjust our social-ecological dispositions and practices in the changing world that we all share.
  • Full Text:
  • Date Issued: 2019

Entrepreneurial intention in the public service of South Africa

  • Authors: Mhlanga, Unathi
  • Date: 2019
  • Subjects: Entrepreneurship , New business enterprises -- South Africa Small business -- Management
  • Language: English
  • Type: Thesis , Masters , MBA
  • Identifier: http://hdl.handle.net/10948/41106 , vital:36357
  • Description: Entrepreneurship is a phenomenon that has been studied across the world by scholars, practitioners and governments. All these different researchers believe that it is a critical tool for economic growth, job creation and enhancing innovation. However, some researchers have conceded that there has been limited research in entrepreneurship and the public service. Thus, this treatise is one of the few studies that have been conducted in entrepreneurial intention in the public service and the examination of entrepreneurial intention of public servants and the factors that influence individuals to opt for employment in the public service. A literature review examining the current knowledge on entrepreneurship, entrepreneurial intention in various contexts was conducted. The reviewed literature allowed for the formation of the base for a conceptual model to be developed. The proposed model claimed that there was a positive influence of culture, family obligations, job security, role modelling, entrepreneurial self – efficacy, access to financial resources and locus of control on the entrepreneurial intentions of public servants in South Africa. Furthermore, the theory of planned behaviour and social learning theory also known as social cognitive theory were explored. There were various statistical analysis tests that were conducted on the quantitative data collected. The mono – method quantitative was used with 280 respondents. Descriptive and inferential statistical tests and exploratory factor analysis were conducted to test the proposed conceptual model. The conceptual model tested consisted of the independent variables; culture, family obligations, job security, role modelling, entrepreneurial self – efficacy, access to financial resources and locus of control with entrepreneurial intention being the dependent variable for assessing the entrepreneurial intention of public servants in the public service of South Africa. The study found that the South African public servants have high entrepreneurial intentions and are very optimistic about creating and running their own business someday. The various statistical analyses split the independent variables from seven to eighteen variables: Family Commitments, Career, Job Purpose, Risk, Access to Knowledge, Entrepreneurship Exposure, Influence, Access to Finance, Financial Support, Business Financing, Entrepreneurial Self-Efficacy, Cultural Perceptions, Societal Standards, Cultural Dedication, Service, Self-Belief and Reward. However, after further analysis of the relationships between the independent variables and the dependent variable, some factors were rejected. A model comprising of factors useful for assessing the entrepreneurial intentions in the public service is recommended with the following factors: Family Commitments, Career, Entrepreneurship Exposure, Entrepreneurial Self-Efficacy, Cultural Perceptions, Societal Standards and Reward. Entrepreneurial Self-Efficacy was found to explain approximately 75% of the movement in the entrepreneurial intentions of public servants. Significant differences on the entrepreneurial intentions of individuals from different races and those who varied according to years of experience were found. The study also found that Culture and Job Security influenced the decision to pursue public service employment. To conclude, the study makes managerial recommendations implementable for government and other stakeholders. Some of the recommendations include incentivising public servants with tax breaks, entrepreneurship courses and easier access to funding to enable them to exit the public service to start their own businesses. Additionally, entrepreneurship education is recommended to become compulsory in schools and for public servants through the National School of Government (NSG). Entrepreneurial ecosystems that encourage pay-it-forward type of interactions were also recommended. Seasoned entrepreneurs can be used as mentors to those public servants who wish to pursue entrepreneurship instead of remaining in the public service.
  • Full Text:
  • Date Issued: 2019

Enumeration, conformation sampling and population of libraries of peptide macrocycles for the search of chemotherapeutic cardioprotection agents

  • Authors: Sigauke, Lester Takunda
  • Date: 2019
  • Subjects: Peptides -- Synthesis , Macrocyclic compounds , Drug development , Drug discovery , Cardiovascular system -- Diseases -- Prevention , Proteins -- Synthesis
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/116056 , vital:34293
  • Description: Peptides are uniquely endowed with features that allow them to perturb previously difficult to drug biomolecular targets. Peptide macrocycles in particular have seen a flurry of recent interest due to their enhanced bioavailability, tunability and specificity. Although these properties make them attractive hit-candidates in early stage drug discovery, knowing which peptides to pursue is non‐trivial due to the magnitude of the peptide sequence space. Computational screening approaches show promise in their ability to address the size of this search space but suffer from their inability to accurately interrogate the conformational landscape of peptide macrocycles. We developed an in‐silico compound enumerator that was tasked with populating a conformationally laden peptide virtual library. This library was then used in the search for cardio‐protective agents (that may be administered, reducing tissue damage during reperfusion after ischemia (heart attacks)). Our enumerator successfully generated a library of 15.2 billion compounds, requiring the use of compression algorithms, conformational sampling protocols and management of aggregated compute resources in the context of a local cluster. In the absence of experimental biophysical data, we performed biased sampling during alchemical molecular dynamics simulations in order to observe cyclophilin‐D perturbation by cyclosporine A and its mitochondrial targeted analogue. Reliable intermediate state averaging through a WHAM analysis of the biased dynamic pulling simulations confirmed that the cardio‐protective activity of cyclosporine A was due to its mitochondrial targeting. Paralleltempered solution molecular dynamics in combination with efficient clustering isolated the essential dynamics of a cyclic peptide scaffold. The rapid enumeration of skeletons from these essential dynamics gave rise to a conformation laden virtual library of all the 15.2 Billion unique cyclic peptides (given the limits on peptide sequence imposed). Analysis of this library showed the exact extent of physicochemical properties covered, relative to the bare scaffold precursor. Molecular docking of a subset of the virtual library against cyclophilin‐D showed significant improvements in affinity to the target (relative to cyclosporine A). The conformation laden virtual library, accessed by our methodology, provided derivatives that were able to make many interactions per peptide with the cyclophilin‐D target. Machine learning methods showed promise in the training of Support Vector Machines for synthetic feasibility prediction for this library. The synergy between enumeration and conformational sampling greatly improves the performance of this library during virtual screening, even when only a subset is used.
  • Full Text:
  • Date Issued: 2019
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