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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.
  • Full Text:
  • 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.
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  • 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.
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  • 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.
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  • 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.
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  • 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.
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  • Date Issued: 2019

Environmental drivers of the composition and distribution of larval fish assemblages off the south coast of South Africa

  • Authors: Trassierra, Jaqueline Anne
  • Date: 2019
  • Subjects: Fishes -- Larvae -- South Africa -- Eastern Cape , Fishes -- Larvae -- Migration -- South Africa -- Eastern Cape , Fishes -- Larvae -- Dispersal -- South Africa -- Eastern Cape
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/68154 , vital:29207
  • Description: The species composition, distribution and patterns of vertical migration of larval fish assemblages were investigated in March and in September 2013 within two adjacent log spiral bays, Algoa Bay and St Francis Bay, on the south coast of South Africa. Fish larvae were collected by means of a boat towed bongo net (57 cm diameter; mesh aperture 500 μm). An onshore (2 km) and an offshore (3 km) station were each sampled twice during the daytime (06:00 – 18:00) with two horizontal tows: near the surface (0.5 m) and close to the bottom (12 m). Tows were repeated at night (18:00 – 23:00) for onshore sites. Larval catches included 16 fish families and 40 species. A multivariate analysis indicated that the species composition was significantly different between Algoa Bay and St Francis Bay, with Engraulidae, Blenniidae, Sparidae, Soleidae and Cynoglossidae making important contributions to the larval fish catch in Algoa Bay, while Blenniidae, Engraulidae, Tripterygiidae, Sparidae and Gobiesocidae contributed significantly in St Francis Bay. Differences in assemblage composition were noted between the Spring (September–October) and Autumn (March-April) months. The species composition of larval fish assemblages was related to wind speed, wave height, cloud cover, sea water temperature, depth, average current speed and direction. Wind speed, wave height, temperature and depth significantly contributed to the variation in larval fish densities. Abundances of larval fishes were greater offshore than onshore, larvae from pelagic eggs dominated catches offshore, while larvae from demersal eggs dominated onshore catches. Habitat structure strongly influenced the composition of larval fishes between the bays and abundances were significantly greater at night than during the day. Most larval fishes displayed a reverse diel vertical migration pattern and were most influenced by predators, wind speed and cloud cover. This study shows that larval fish assemblages are highly complex and patchy. Spawning mode, individual species behaviour, diel vertical migration, current structure, depth, temperature, wind speed, cloud cover and type of habitat substratum all influence larval fish composition and distribution in the nearshore waters of South Africa.
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  • Date Issued: 2019

Environmental niche patterns of native and non-native fishes within an invaded African river system

  • Authors: Kadye, Wilbert T , Booth, Anthony J
  • Date: 2019
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/124407 , vital:35605 , https://doi.10.1111/jfb.13988
  • Description: To test ecological niche theory, this study investigated the spatial patterns and the environmental niches of native and non-native fishes within the invaded Great Fish River system, South Africa. For the native fishes, there were contrasting environmental niche breadths that varied from being small to being large and overlapped for most species, except minnows that were restricted to headwater tributaries. In addition, there was high niche overlap in habitat association among fishes with similar distribution. It was therefore inferred that habitat filtering-driven spatial organization was important in explaining native species distribution patterns. In comparison, most non-native fishes were found to have broad environmental niches and these fishes showed high tolerance to environmental conditions, which generally supported the niche opportunity hypothesis. The proliferation of multiple non-native fishes in the mainstem section suggest that they form a functional assemblage that is probably facilitated by the anthropogenic modification of flow regimes through inter-basin water transfer. Based on the distribution patterns observed in the study, it was inferred that there was a likelihood of negative interactions between native and nonnative fishes. Such effects are likely to be exacerbated by altered flow regime that was likely to have negative implications for native ichthyofauna.
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  • Date Issued: 2019

Epibenthic biodiversity, habitat characterisation and anthropogenic pressure mapping of unconsolidated sediment habitats in Algoa Bay, South Africa

  • Authors: Truter, Hannah Jessie
  • Date: 2019
  • Subjects: Aquatic ecology , Marine sciences Conservation biology Ecology
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10948/43812 , vital:37049
  • Description: Implementation of an ecosystem-based management approach for marine systems requires a comprehensive understanding of the biophysical marine environment and the cumulative human impacts at different spatio-temporal scales. In Algoa Bay, South Africa, this study describes the epibenthic communities occurring in unconsolidated marine habitats. It further investigates the potential abiotic factors that influence their distribution and abundance, compares epibenthic communities with existing habitat information and evaluates the protection status of the marine environment in the Bay. Seabed imagery, covering a total area of 171.4m², and sediment samples were collected from 13 stations from which 106 epibenthic species were identified. Multivariate analyses revealed two statistically distinct communities that did not align with the Algoa Bay benthic habitat types defined in the current National Biodiversity Assessment (NBA, 2012). Further assessment indicated that community differences were driven by the presence of rock substrate. A range of abiotic factors were tested against the epibenthic communities to explore patterns and identify potential drivers. The combination of abiotic factors depth, mean grain size, mean bottom temperature and mean bottom current explained 55% fitted variation in epibenthic data. The degree of long-term variability in several of these parameters were likewise identified as explanatory variables, including bottom temperature, current speed and dissolved oxygen. The link between abiotic factors and the epibenthic communities observed indicate that these variables can act as surrogates for habitat mapping in the future. The existing and proposed Marine Protected Area (MPA) in conjunction with the NBA 2012 habitat types does well in protecting the majority of habitats in the Bay, however there remain habitats that lack protection. Utilising the benthic communities and potential drivers identified in this study, the proposed MPA boundary delineations should be somewhat altered to include missing habitat types.
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  • Date Issued: 2019

Equal pay for work of equal value

  • Authors: Leo, Aloshea Doreen
  • Date: 2019
  • Subjects: Equal pay for equal work -- Law and Legislation -- South Africa , Pay equity -- South Africa Labor laws and legislation -- South Africa
  • Language: English
  • Type: Thesis , Masters , LLM
  • Identifier: http://hdl.handle.net/10948/40445 , vital:36166
  • Description: Since the end of the Apartheid Regime, various labour legislation has been enacted over the years to eliminate discrimination and grant everyone in South Africa the right to fair labour practices, including the prohibition of unfair payment practices in terms of item 2(1)(a) of Schedule 7 of the Labour Relations Act.1 The above item was repealed and replaced with an express provision strictly prohibiting unfair discrimination in any employment practice or policy.2 However, even though this express provision strictly prohibited unfair discrimination in employment, the International Labour Organisation criticised South Africa for the failure to include an express provision dealing specifically with equal remuneration in terms of the Employment Equity Act.3 Because of this criticism, sections 6(4) and (5)4 were introduced. Section 6(4) amendments were obviously not been successful as intended, as numerous employees still are facing unfair discrimination based on the wages. Looking at Case law in the United Kingdom, there are clearly principles and successes that South Africa can learn from and incorporate in South African labour law. Some successes include the proactivity of employers who identify groups of employees, which are performing work that is of equal value, comparing their salaries, and by investigating and removing pay gap causes. Another success is the use of reports of independent experts who can assess the value of different occupations. If South Africa does this, it will alleviate the pressure placed upon courts that do not have the necessary expertise to decide on the value.
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  • Date Issued: 2019

Establishing baseline data of Cradock and Tarkastad’s communities’ disease profile ahead of hydraulic fracturing and shale gas development

  • Authors: Olivera, Shanene
  • Date: 2019
  • Subjects: Medical care -- South Africa -- Eastern Cape , Diseases -- South Africa -- Eastern Cape South Africa -- Eastern Cape -- Statistics, Medical Surveys
  • Language: English
  • Type: Thesis , Masters , MCur
  • Identifier: http://hdl.handle.net/10948/43088 , vital:36734
  • Description: The South African government is investigating alternative ways to address the electricity crisis and has identified fracking as an alternative energy source. Specific areas have been identified for the implementation of Shale Gas Development. Various research studies have connected fracking to the incidence of certain diseases. Since Cradock and Tarkastad have been identified as prospective areas for the implementation of fracking, the primary aim of this study was to determine the disease profile of the community members in Cradock and Tarkastad. This baseline data could be utilised at a later stage as a benchmark when similar studies are conducted after the implementation of Shale Gas Development in these communities. A quantitative approach utilising a comparative descriptive survey design was adopted to conduct this study. The research population comprised all community members in Cradock and Tarkastad. A multi-staged sampling process was applied namely, cluster, convenient and stratified random sampling process; 489 respondents were included in the research sample. Two structured questionnaires and checklists were developed and administered by Registered Nurses, who were recruited as fieldworkers, to collect the data for the study. One questionnaire and checklist were designed and used for the age groups five-year and under population (n=43), and the other questionnaire and checklist were used for the over five-year population group (n=446). This allowed for the establishment of a disease profile of all ages in both areas. Descriptive and inferential statistics were used to analyse the data, and a pilot study was conducted before the primary study. The results of the study revealed the current disease profile in Tarkastad and Cradock. One of the objectives of the study was to compare the prevalence of diseases and abnormalities found in Cradock and Tarkastad. Thereafter the disease profiles were combined in a single profile for both Cradock and Tarkastad. Statistical analysis among the five-year-old and under population group indicated significant associations between area and physiological status, birthweight and physical conditions identified and monthly household income and physiological status (p<0.05). The over five-year-old population group revealed a greater significance between the independent and dependent variable categories than in the age group five years and under. The study revealed that South Africa’s burden of disease is evident in these findings with HIV/AIDS topping the list. The prevalence rates of HIV/AIDS and Hypertention are higher than the national prevalence rates, in Cradock and Tarkastad. It was also worthwhile to mention that Tarkastad faces more socio-economic challenges compared to Cradock. Recommendations were made for nursing practice, nursing education and further development of nursing research based on the research findings.
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  • Date Issued: 2019

Establishing computational approaches towards identifying malarial allosteric modulators: a case study of plasmodium falciparum hsp70s

  • Authors: Amusengeri, Arnold , Astl, Lindy , Lobb, Kevin A , Verkhivker, Gennady M , Tastan Bishop, Özlem
  • Date: 2019
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/163000 , vital:41003 , https://doi.org/10.3390/ijms20225574
  • Description: Combating malaria is almost a never-ending battle, as Plasmodium parasites develop resistance to the drugs used against them, as observed recently in artemisinin-based combination therapies. The main concern now is if the resistant parasite strains spread from Southeast Asia to Africa, the continent hosting most malaria cases. To prevent catastrophic results, we need to find non-conventional approaches. Allosteric drug targeting sites and modulators might be a new hope for malarial treatments. Heat shock proteins (HSPs) are potential malarial drug targets and have complex allosteric control mechanisms. Yet, studies on designing allosteric modulators against them are limited. Here, we identified allosteric modulators (SANC190 and SANC651) against P. falciparum Hsp70-1 and Hsp70-x, affecting the conformational dynamics of the proteins, delicately balanced by the endogenous ligands. Previously, we established a pipeline to identify allosteric sites and modulators. This study also further investigated alternative approaches to speed up the process by comparing all atom molecular dynamics simulations and dynamic residue network analysis with the coarse-grained (CG) versions of the calculations. Betweenness centrality (BC) profiles for PfHsp70-1 and PfHsp70-x derived from CG simulations not only revealed similar trends but also pointed to the same functional regions and specific residues corresponding to BC profile peaks.
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  • Date Issued: 2019

Evaluating Livestock Development Programmes through the Production Risk Interface: Case of the Kaonafatso ya Dikgomo (KyD) Scheme in South Africa

  • Authors: Ngarava, Saul
  • Date: 2019
  • Subjects: Livestock projects
  • Language: English
  • Type: Thesis , Doctoral , Degree
  • Identifier: http://hdl.handle.net/10353/15730 , vital:40513
  • Description: Livestock is significant in the livelihoods of the rural poor, providing a plethora of benefits. Livestock Development Programmes (LDPs) can transform smallholder farmers’ production for increased production and poverty reduction. The Kaonafatso ya Dikgomo (KyD) Scheme is a LDP implemented in South Africa with the aim of assisting smallholder farmers to attain economic and sustainable beef production. The literature shows that most evaluations of LDPs have been quantitative based on measurable and quantifiable metrics. Furthermore, various socio-economic and institutional factors have a bearing on the decision to participate in LDPs and eventually adopting the practices. Impact assessments of LDPs have been devoid of risk consideration as well as ascertaining how risk introduced by participating in LDPs has impacted productivity. The overall objective of the study was therefore to evaluate LDPs, focussing on benefits, participation and risk. The specific objectives of the study entailed developing a conceptual tool for measuring the qualitative and secondary benefits. Secondly, it was to determine factors influencing participation decisions in the KyD Scheme. Thirdly, the study sought to measure and compare calving rate and off-take rate risk between KyD Scheme participants and non-participants. Lastly, the study highlighted the variability (risk) introduced by participating in a LDP and its impact on production. The study utilised a cross-sectional survey of KyD Scheme participants and nonparticipants in KwaZulu-Natal, Limpopo and Eastern Cape Provinces of South Africa. Non-probability convenience sampling method was utilised in selecting a sample of 164 KyD Scheme participants and 81 non-participants. A semi-structured questionnaire was the data collection tool utilised. A conceptual “Livelihood Effect Benefit Index”; Probit, Tobit and Ordered Probit models; Just and Pope Production function; Propensity Score Matching; and Monte Carlo Simulations were utilised to analyse data. Statistical Package for Social Scientists version 24, STATA 13 and @Risk Decision Tool were the analytical packages utilised in analysing the data. The study found that the Scheme provided low qualitative benefits, mainly through social capital. Furthermore, socio-economic and institutional factors have significant impact on the decision to participate in the Scheme, extent of participation and decision to continue practicing Scheme experiences. In comparing the two groups of Scheme and Scheme non-participants, calving and off-take risk for KyD Scheme participants was lower than that of Scheme non-participants. In comparing individuals with similar characteristics between the two groups, Scheme participants reduced calving risk whilst increasing the off-take risk. Page | vi The study concluded that the Scheme exhibited low qualitative benefits. Furthermore, the decisions to participate and the extent of participation in the KyD Scheme were influenced by various socio-economic and institutional factors, which were however more favourable to resource endowed smallholder farmers. In addition, the Scheme had significant impact on production risk. The risk reducing determinants appeared to also favour more resource endowed smallholder farmers who had more farming experience. The study’s recommendations were subdivided into short term, medium term and long term. The short term recommendations included targeting farmers within a distance of between 30km and 90km from a formal market, promoting dipping services-based training and extension, and providing information and training concerning calving i.e. animal health, husbandry and breed selection for herd maximization. Participation in the Scheme and the extent of participation can be improved through enhancing awareness of the Scheme at various points where stock feed are available to farmers. Furthermore, enhanced cooperation with extension workers provides a conduit in improving awareness of the Scheme and enhancing participation. The medium term recommendations pertained to initiatives such as promoting other livelihood options to enhance benefits of the programme, and promoting social capital enhancing initiatives such as mentoring and providing social capital objectives that can be integrated into the overall livestock sector strategy. The long-term recommendations include initiatives such as subsidizing increase in herd size to between 50 and 120 cattle, maintaining a monthly frequency of farmer-extension contact of between 2 and 5 times per month, as well as incorporating calving and off-take risk in policy formulation, implementation and evaluation
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  • Date Issued: 2019

Evaluating the benefits of the extended public works programme in the Buffalo City Metropolitan Municipality

  • Authors: Lindani-Beni, Bulelwa
  • Date: 2019
  • Subjects: Public service employment -- South Africa -- Eastern Cape , Community development -- South Africa -- Buffalo City Metropolitan Municipality Job creation -- South Africa -- Buffalo City Metropolitan Municipality Public works -- South Africa -- Buffalo City Metropolitan Municipality
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10948/40555 , vital:36182
  • Description: Public Works Programmes (PWPs) are interventions implemented by the government to overcome the high levels of unemployment and to provide the poor with salaries so that they can meet their basic needs. This was done in response to the United Nations (UN) call to meet the sustainable development goals adopted in 2015. The study defines PWPs and gives an overview of the categories of the intervention programmes. Different countries use the PWPs for different aims from poverty reduction, response to economic shocks and guaranteed employment. Most of the countries, like South Africa, use these programmes as a temporary relief. Unemployment remains a challenge in the Buffalo City Metropolitan Municipality (BCMM) and the municipality has always been unsuccessful in reaching the targets expected in job creation. The study compares the South African Extended Public Works Programme (EPWP) with the two other international programmes, India and Malawi. The analysis of the three phases of the South African EPWP since its inception in 2004 is done in this study. The paper analysed the BCMM’s EPWP projects in the Eastern Cape where there is a high level of unemployment and a high degree of rural-urban migration. An overview of the Malawi Social Action Fund (MASAF) and India’s National Rural Employment Guarantee Scheme (NREGA) is also presented in this study. The researcher analysed documents and desktop reviews for the study. The available information such as the programme strategic plans, logical frameworks, policy documents, implementation reports, academic journals and media reports were consulted for this study. The study highlighted challenges in the South African EPWP which contributes towards the inefficiency of the programme in reducing the high levels of unemployment in the BCMM. The researcher provided recommendations that may improve the effectiveness of the public works programme in South Africa. One recommendation is the development of a Management Information System for EPWP that can assist the government in monitoring and evaluating the whole programme in the different departments and municipalities.
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  • Date Issued: 2019

Evaluating the Prevention of Mother to Child Transmission (PMTCT) of HIV Services in the Eastern Cape: subtitle if needed. If no subtitle follow instructions in manual

  • Authors: Sigovana, Khuthala
  • Date: 2019
  • Language: English
  • Type: Masters theses , text
  • Identifier: http://hdl.handle.net/11260/3176 , vital:43182
  • Description: Abstract text To effectively reduce HIV transmission to newborns requires a reduction of HIV prevalence among pregnant women and a full understanding of its epidemiology. There is however, a literature gap: few recent HIV studies focus on women attending antenatal care in rural areas in South Africa. A Cross-sectional study of women attending antenatal care in four Primary Care facilities was conducted. An interviewer-administered questionnaire to collect information on socio-demographic characteristics and medical history was used. Binomial logistic regression analyses were used to determine factors associated with HIV and to estimate the prevalence ratio (PR). The 95% confidence interval (CI) is used for precision of estimates; p≤0.05 for statistical significance. A total of 343 participants were recruited. Most participants (n = 341 or 99.42%; CI: 97.91 – 99.93) knew their HIV status. The antenatal HIV prevalence was 38.19% (CI: 33.17 – 43.48). Participants older than 40 years were 3.99 and 3.81 times more likely to be HIV positive compared to teenagers (PR = 3.99; CI: 1.11 – 14.30; pstxvalue = 0.034) and those in the 20-29 age group (PR = 3.81; CI: 1.07 – 13.60; pstxvaluevalue = 0.039) respectively; and this was statistically significant. Unemployed participants were 34% (PR = 1.34; CI: 1.16 – 1.55; p-value less than 0.0001) and 41 percent (PR = 1.41; CI: 1.23 – 1.61; p-value less than 0.0001) more likely to be HIV positive when compared to tertiary students and self-employed individuals respectively. The antenatal HIV prevalence remains high and is increasing in this population. However, findings suggest a changing and maturing epidemic. , Thesis (MMED) -- Faculty of Health Sciences, 2019
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  • Date Issued: 2019

Evaluation of Crime Prevention through Environmental Design Principles at the University of Fort Hare, Alice Campus

  • Authors: Mditshwa, Abongile Sisanda
  • Date: 2019
  • Subjects: Crime prevention
  • Language: English
  • Type: Thesis , Masters , MSoc.Sci (Criminology)
  • Identifier: http://hdl.handle.net/10353/17695 , vital:41137
  • Description: The University of Fort Hare Alice campus experiences high crime rates. To address this problem, and add to the literature, this study applied the Crime Prevention through Environmental design (CPTED) model to measure the effectiveness of the crime prevention strategies at the University of Fort Hare (Alice campus). The aim of this study was to evaluate the sufficiency of surveillance and visibility, target hardening, maintenance and management at the University of Fort Hare, which contribute to the reduction of criminal activities around campus. The study further sought to evaluate the perceptions of students regarding their safety on campus by way of soliciting their experiences and observations. This study used the quantitative method, and questionnaires were distributed to the students in the Alice campus to collect data. The study found that whilst a marginal majority of students felt safe, a large proportion of students felt unsafe on campus. The study also found that students were dissatisfied with the service and found the security officers to be incompetent and un-trained. The study evaluated the sufficiency of crime prevention measures implemented within the university. One crucial aspect that emerged from the study is that CPTED principles were not sufficiently implemented to their fullest and the perception of the majority of students was that security personnel were not functioning in the way that they should, and measures such as adequate lighting were lacking. As a result, students felt unsafe on campus, especially during the night .The study concluded that there are clear increased feelings of vulnerability among students at the University of Fort Hare. The measures that are currently in place are not sufficient; therefore there is need for implementation of CPTED principles. It was recommended that the University increases number of CCTV surveillance cameras on campus, Social gathering places be surrounded by security guards for patrols, lighting recommendations that are modern and in proper design, keep up with repairs, make necessary replacements, paint, trim, current campus buildings e updated to meet recent CPTED practises etc.
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  • Date Issued: 2019

Evaluation of groundwater potential based on hybrid approach of geology, geophysics, and geoinformatics: Case study of Buffalo Catchment area, Eastern Cape, South Africa

  • Authors: Owolabi,Solomon T
  • Date: 2019
  • Subjects: Hydrogeology Geology
  • Language: English
  • Type: Thesis , Doctoral , PhD (Geology)
  • Identifier: http://hdl.handle.net/10353/12238 , vital:39218
  • Description: This study focuses on the feasibility of exploring potential groundwater zones through assessment of catchment geo-hydrodynamic processes, using hydro-statistic principles and geographic information system-based approaches. The research work integrated analysis of hydrologic variables, geologic structures, and geomorpho-tectonic processes that provide information on spatial variability of hydrologic units in a watershed. The study is aimed at improving conceptual knowledge and presenting the technical feasibility of exploring potential groundwater zones through geo-hydrodynamic perspectives in hydrogeologically challenged environments. The study adopted a case design approach at the Buffalo hydrologic basin headwater in Eastern Cape, South Africa. The methods used in this study include: field mapping of geologic units and structures, digital processing of aeromagnetic map, cross-section profiling of borehole logs, auto-extraction of lineament, streamflow variability and recession assessment, geomorpho-tectonic analysis of surficial drainage pattern, vertical electrical sounding for imaging shallow subsurface layers, and geospatial integration of thematic maps of groundwater multi-influencing factors. The results indicate that the hydrogeological settings of Buffalo watershed comprised of good, moderate, fair, poor and very poor groundwater potential zones which cover 187 km2 , 338 km2 , 406 km2 , 185 km2 , and 121 km2 respectively. The results report that the groundwater system of Buffalo watershed is mainly hosted by the well-drained fractured dolerite and the shallow unconfined sandstone aquifer. The aquifer is bounded by two parallel impermeable valley walls in the north and south. Also, the Buffalo drainage system constitutes a variable head boundary as a groundwater discharge zone. The groundwater discharge which mostly occurs at the Tshoxa upper course, Mgqakwebe, Quencwe, Yellowwoods upper course and the Buffalo River center influence the status of the Buffalo River as a perennial river system. vi The groundwater recharge occurs through the networks of surficial lineaments and fractures concentrated on the sandstone lithosome, mostly in the northern half of the watershed. The surficial tectonic features trend in a WNW-ESE and E-W direction. The groundwater flow system is controlled by the subsurface lineaments which are oriented in west-northwest – eastsoutheast direction. Most of the groundwater recharge is driven by rain which is extreme at the north. The hydro-climatic pattern of the region influences the dendritic drainage system of Buffalo watershed. The geologic characterization and geomorpho-tectonic analysis indicate that the geologic settings are made up of upward-fining lithologic material and siliciclastic materials that were deposited as fill in paleochannels by braided and meandering fluvial systems. The variability in dissection property and the fluvial system indicates that Buffalo hydrologic and geomorphic systems are heterogeneous and complex. The possible impact of these variabilities aligns with the report of geoelectric sections which revealed the heterogeneity of the aquifer intrinsic properties and variability in groundwater yield. The electric resistivity tomography revealed the existence of a fault system and variation in the thickness of the aquifer. Hydrologic characterization indicates the vulnerability status of the rivers within the watershed. In particular, the Ngqokweni River is vulnerable to diminution while Quencwe River has the potential for a flash flood. Buffalo station is an important surface water capture zone. Delineation of groundwater potential zone should incorporate geologic, hydrologic, geophysical, geomorphotectonic, and environmental perspectives due to the inherent relationship among influencing factors. The study therefore identifies groundwater capture zones which can be further explored for groundwater development and to mitigate the stake of water shortage. The study therefore recommends the approach here to the department of water affairs for adoption to map the zones of groundwater potential at a regional scale. The study also provides resourceful information on vii groundwater recharge zones and therefore recommends that the environment and water stakeholders work together to protect the recharge zones from groundwater contamination due to land use
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  • Date Issued: 2019

Evaluation of pre-treatment methods on production of bioethanol from bagasse and sugarcane trash

  • Authors: Dodo, Charlie Marembo
  • Date: 2019
  • Subjects: Lignocellulose
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10353/15387 , vital:40403
  • Description: A variety of methods have been researched on for bioethanol preparation from different feedstocks. Amongst the available feedstock, one such feedstock is the sugarcane plant. In most of the research on bioethanol preparation with sugarcane the sugary juice has been widely used, with the bagasse and trash having been discarded as waste. The “waste” bagasse and trash are usually removed and thrown away or burnt during harvesting or in sugar mills to supplement energy requirements. This research on lignocellulosic bagasse and trash was done so as not to discard them but to rather find ways in which to use this biomass constructively. Alternatives to burning that can potentially add value to this biomass need to be researched on by evaluating their hydrolysis content. The different lignocellulose pretreatment methods of concentrated and dilute acid pretreatment, with subsequent enzyme hydrolysis as well as alkali and oxidative alkali pretreatment with enzyme hydrolysis were experimented on the bagasse and trash for hydrolysis efficiency and effectiveness. There are two types of acid hydrolysis which were investigated on which are concentrated and dilute sulphuric acid pretreatments. Use of concentrated sulphuric acid yielded the highest amounts of reducing sugars but also resulted in the highest amounts of downstream process inhibitors formation. This resulted in the need for neutralisation steps which in turn increase the overall costs of using this method to obtain reducing sugars. It has however the advantage of occurring at a faster rate, within minutes or hours, than using biological enzymes which took days, up to 72 hours to obtain the highest reducing sugar amounts. Dilute sulphuric acid pretreatment offered the advantage of using fewer chemicals which are therefore less severe on equipment and result in fewer fermentation inhibitors being formed. Dilute sulphuric acid hydrolysis also takes a relatively shorter period than biological methods of pretreatment. A challenge of fermentation inhibitors formed during acid hydrolysis was countered by using the methods of overliming (calcium hydroxide) and comparing it to neutralization with sodium hydroxide. Alkali pretreatment with sodium hydroxide was researched on by applying different pretreatment concentrations during experiments on the lignocellulosic biomass. There was an increase in the available quantities of cellulose with a significant reduction in lignin with pretreatment. Alkali pretreatment proved effective in exposing the cellulose which made v more cellulose surface area available to cellulase enzymes for enzyme hydrolysis. The highest yield of reducing sugars was obtained from hydrolysates pretreated with 0.25 M sodium hydroxide for 60 min and a period of 72 h of enzyme hydrolysis. In general the longer the pretreatment time the more reducing sugars were produced from the enzyme hydrolysis. Alkali peroxide pretreatment also resulted in significant reductions in lignin quantities of lignocellulose material. In this method sodium hydroxide in combination with hydrogen peroxide were used in pretreating the biomass. Hydrolysates with even fewer fermentation inhibitors were produced as a result. The highest percentage concentration of cellulose of 63% (g/g) was achieved after pretreatment of bagasse with 5% alkali hydrogen peroxide and trash with 0,25M sodium hydroxide pretreatment. Pretreatment of biomass using alkali with subsequent enzymatic hydrolysis gave the highest yields of fermentable sugars of 38% (g/g) using 7% (v/v) alkali peroxide pre-treated trash than 36% (g/g) for 5% (v/v) with the least inhibitors. Reducing sugar yields of 25% (g/g) and 22% (g/g) were obtained after pretreatment with concentrated and dilute acid respectively. Neutralization of the acid hydrolysates was necessary to reduce inhibitors formed with neutralisation by sodium hydroxide resulting in low dilutions and loss of fermentable sugars as unlike in the case of overliming. Subsequent steps of fermenting the reducing sugars resulting from pretreatment into bioethanol were based on using the yeast Saccharomyces cerevisae. Pretreatment hydrolysates from alkali peroxide experiments produced higher bioethanol yields of 13.7 (g/l) after enzyme hydrolysates versus 6.9 (g/l) bioethanol from dilute acid hydrolyzates. A comparison of the effects of time showed there was more bioethanol yield of 13.7 (g/l) after 72 h of fermentation with the yeast versus 7.0 (g/l) bioethanol after pretreatment for 24 h. The only drawback is the longer fermentation period which thus reduces the process and so reduces the value of the increase in yield
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  • Date Issued: 2019

Evaluation of SNPs of G6PD, with regard to the 3D conformational, structural and stability alterations, in order to investigate the clinical implications and potential applications

  • Authors: Sanabria, Natasha Mary-Anne
  • Date: 2019
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/76500 , vital:30574
  • Description: Expected release date-April 2020
  • Full Text: false
  • Date Issued: 2019

Evaluation of some Eastern beach bacteria for high activity laccase production

  • Authors: Ntlatywa, Nonkolisi
  • Date: 2019
  • Subjects: Laccase
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/${Handle} , vital:40025
  • Description: Laccases are multi-copper oxidases endowed with huge applicability and versatility. They are found in nature, fungi, insects, archaea and bacteria; however, there is a dearth of information regarding bacterial laccases. Thus, the search for novel bacterial laccases becomes crucial. Therefore, the broad aim of the study was the assessment of some bacteria on marine water isolated from Eastern beach for the production of high activity laccases. In this study, marine water samples obtained from the Eastern beach in East London were investigated for bacterial laccase-producing isolates. The samples were analysed using different microbiological media and varied substrates via qualitative methods. The isolates were tested for laccase activity using ABTS (2, 2’- azinobis 3-ethyl-benzothiazoline-6-sulphonate), as a substrate. The present study also dealt with the optimization of culture conditions for laccase production and characterization of laccase. A total of forty-eight (48) bacterial isolates were obtained, which were identified based on their morphological and cultural characteristics. Many of the isolates (42) were categorized as Gram positive and a few (6) as Gram negative upon subjecting to microscopic examination. Result showed that on average, laccase activity ranged from 5.33 – 6.5 U/L as demonstrated by three bacterial isolates (Bacillus sp. NFN1, Bacillus sp. NLN and Escherichia coli LO). Laccase production was highly enhanced by the supplementation with vanillic acid by Bacillus sp. strain NLN with yield of 15.83 ± 0.7 U/L, Bacillus sp. strain NFN1, 12.72 ± 0.21 U/L. However, Escherichia coli LO demonstrated enhanced laccase production with guaiacol (12.84 ± 1.12 U/L) followed by ferrulic acid (12.8 ± 0.36 U/L). While optimization results revealed that the laccase yield was enhanced under the following conditions: 72 h of incubation, pH 5, 0.5mg/L lactose as a carbon source, 1. 5 mg/L yeast extract as a nitrogen source as well as in the presence of corn stover and mandarin peels as lignocellulosic substrates depending on the bacteria.The time course and stability of laccase against temperature, pH, metal ions and organic solvents were investigated using previously described methods. In the findings obtained for the time course, the laccase activity ranged from 22.2- 23.98 U/L. In general, the optimum parameters for the optimum laccase activities depended on the bacterial isolates and the time of incubation and included 80 °C and 70 °C, pH 3 and 9 while, the thermal stability was over 100%. Overall, NaCl, ZnSO4, NiCl and 20% acetone demonstrated positive effect on the residual activity of the laccases of all the bacterial isolates (Bacillus sp. NFN1, Bacillus v sp. NLN and Escherichia coli LO). In conclusion the findings of the study, suggest that marine water of the Eastern beach is a rich source for laccase producing bacteria with potential of high activity.
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  • Date Issued: 2019
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