List of Titles

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The impact of total productive maintenance (TPM) on manufacturing performance at the Colt Section of DaimlerChrysler in the Eastern Cape

- Ncube, Mfowabo

Authors: Ncube, Mfowabo
Date: 2006
Subjects: Total productive maintenance , Plant maintenance -- Management , Automobile industry and trade -- South Africa -- Eastern Cape
Language: English
Type: Thesis , Masters , MBA
Identifier: vital:8560 , http://hdl.handle.net/10948/579 , Total productive maintenance , Plant maintenance -- Management , Automobile industry and trade -- South Africa -- Eastern Cape
Description: Today's successful manufacturing organisations require a significant competitive advantage, hence the need to implement and develop a Total Productive Maintenance (TPM) strategy. This research paper addresses the impact of TPM on manufacturing performance at the Colt production facility (DCSA). A literature survey was undertaken into the elements and benefits of TPM. Questionaires were also sent to all levels of people at the Colt production facility for their views on TPM and the impact, they believe, it has had on manufacturing performance. In conclusion, this research paper has also led to the development of recommendations to improve TPM activities at the Colt production facility. From the research, it was shown that top management support for TPM activities is needed and that training is an essential factor for TPM's success in improving manufacturing performance.
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Hsp40 Co-chaperones as drug targets: towards the development of specific inhibitors

- Pesce, Eva-Rachele, Blatch, G L, Edkins, Adrienne Lesley

Authors: Pesce, Eva-Rachele , Blatch, G L , Edkins, Adrienne Lesley
Date: 2016
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/66335 , vital:28937 , https://doi.org/10.1007/7355_2015_92
Description: publisher version , The heat shock protein 40 (Hsp40/DNAJ) family of co-chaperones modulates the activity of the major molecular chaperone heat shock protein 70 (Hsp70) protein group. Hsp40 stimulates the basal ATPase activity of Hsp70 and hence regulates the affinity of Hsp70 for substrate proteins. The number of Hsp40 genes in most organisms is substantially greater than the number of Hsp70 genes. Therefore, different Hsp40 family members may regulate different activities of the same Hsp70. This fact, along with increasing knowledge of the function of Hsp40 in diseases, has led to certain Hsp40 isoforms being considered promising drug targets. Here we review the role of Hsp40 in human disease and recent developments towards the creation of Hsp40-specific inhibitors.
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Rural students' local knowledge of learning in formal and informal contexts

- Visser, Alvin-Jon

Authors: Visser, Alvin-Jon
Date: 2000
Subjects: Non-formal education -- South Africa , Education and state -- South Africa , Rural children -- Education -- South Africa , Blacks -- Education -- South Africa , Community and school -- South Africa , Education, Rural -- Social Aspects -- South Africa , Rural schools -- South Africa
Language: English
Type: Thesis , Masters , MA
Identifier: vital:3079 , http://hdl.handle.net/10962/d1002588 , Non-formal education -- South Africa , Education and state -- South Africa , Rural children -- Education -- South Africa , Blacks -- Education -- South Africa , Community and school -- South Africa , Education, Rural -- Social Aspects -- South Africa , Rural schools -- South Africa
Description: The general aim of this thesis is to illuminate the process of learning as it occurs in formal and informal contexts. The study focuses on South African scholars attending school in rural areas where the contrast between learning in formal and informal learning contexts is more pronounced than that in urban areas. The research draws on rural scholars' local knowledge of formal and informal learning contexts in order to gain a rich insight into how cognition is situated in different learning contexts. This is accomplished through investigating the structure of the respective learning tasks, the mediators involved, the task objectives and the means for achieving these objectives in the different learning contexts. The thesis draws on a socio-cultural approach to the study of cognitive development to probe the activity of learning in a formal and informal learning context. Through the use of a context sensitive methodological methods especially Participatory Rural Appraisal (PRA) tools and techniques, it was possible to illuminate tacit local knowledge structures and to get participants to actively explicate their understandings related to learning in different contexts The research results illustrate the assertion that the activity of learning is fundamentally situated in the learning context from which it arises. Learning is framed by the community of practice which structures affordances for situated learning, through mediation, within zones of proximal development. Learning in a formal context such as the school is often abstract, rule-based, standardised and theory related. Learners also find it difficult to reflect on the learning tasks and the mediational means used in a formal learning context. In contrast, the learning which takes place in an informal setting is often practical, individualised, flexible and environment based. This learning is structured around everyday activities and is dynamically defined and supported. In a situation where a learner is exposed to dislocated learning contexts, the essential goal of educational initiatives is to bridge the gap between the two. This can be achieved through mediators creating effective zones of proximal development which facilitate the individuals adaptation between learning contexts. Exposing rural scholars' local knowledge of learning in formal and informal contexts allows for a fuller understanding of the cognitive development structured within formal and informal communities of practice. It is this understanding that is necessary to address the situation where learning contexts, drawing on different knowledge bases find ways of thinking, prove challenging and/or conflicting to the scholar.
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A Cost-Efficient Energy Management Model for ICT4D Platforms in Low Resource Communities

- Mbotoloshi, Dumisani

Authors: Mbotoloshi, Dumisani
Date: 2018
Subjects: Information technology , Communication in community development|
Language: English
Type: Thesis , Masters , MSc (Computer Science )
Identifier: http://hdl.handle.net/10353/14538 , vital:39999
Description: A couple of Information and Communication Technology (ICT) researches have been conducted in the rural communities of South Africa (SA). This has encouraged the development of ICT services such as e-government, e-commerce, e-judiciary, e-health, e-agriculture and many others. Proper ICT implementation has led to societal development, economic empowerment and sustainable communities. However, this is achieved after intensive planning and stakeholders‟ involvement. It is clear that ICTs require energy to function. Most significantly is the fact that a bulk of ICTs in low resource communities (LRC) are mainly donations and less consideration if any is made on their energy consumption. LRC are regions with minimum access to energy, clean water, educational facilities, health facilities, government facilities, technology etc. There have been debates on whether in LRC ICTs are consuming energy. Most ICTs have been deployed without much consideration on the required energy consumption. On the other hand, less research has been done on the sustainability of ICTs, especially considering that all ICT devices and related platforms rely on the availability of energy. There are a lot of possible low cost energy solutions that are available, which could be used to support ICTs in LRC. However, there are so many ICT services, devices and platforms that are lying idle and not been fully utilized in such areas due to the energy related issues. In most cases, ICT solutions in LRC are introduced mainly with Computer Science and Information Systems researchers, without including other key stakeholders like energy experts. The research presents a Cost Effecient Energy Management Model that could be used to assist ICT for Development (ICT4D) platforms or projects in LRC. Both qualitative and quantitative research methods were used within the Siyakhula Living Lab (SLL) in Eastern Cape (EC) Province of SA. Design Science theory is considered for the designing of the model. The SLL is an ICT project which is undertaken within the Dwesa, Bulembu and Alice rural communities. In this dissertation, Dwesa rural community is the chosen case. The surrounding schools in the communities have been used as the ICT point of contact. Interviews, questionnaires, literature v review, action research, focus group, experiments, formulas and evaluation were the specific methods used to conduct this research. Results show that ICTs deployed in the SLLs are mainly donations which consume much energy. The main source of energy use within the SLLs is electricity. From the three schools that were selected where ICTs have been deployed it was found that the electricity bill has increased enormously. This has caused some schools not to open the computer laboratories, which are supposed to be used by the community members. It was also found that there is no energy management plan or solution in place for the SLL resources. The findings show that ICTs within the SLL are been affected by energy related subjects, though the community has been willing to pay for electricity. The Cost Efficient Energy Management Model is proposed at the end of the dissertation. The model is targeted for ICT service providers and has five (5) main pillars i.e stakeholders‟ engagement, energy and ICT infrastructure, new business models, monitoring and evaluation, and finally awareness and training. The dissertation identified all the ICT resources and services at three selected schools within the SLL and drew up the energy consumption for each school. All schools indicated that there has been an increase in the electricity bill after the introduction of the SLL project. There was a clear indication that no energy expert was involved in the establishment of the SLLs. The dissertation indicates that there is a need for renewable source of energy for ICTs to improve service delivery in LRC. ICT service providers should consider energy subjects when planning for development of such solutions in LRC. This research focuses on designing a low cost ICT energy model to inform on ICTs energy consumption in LRC. It further outlines the possible ICT energy solutions that could be used to benefit targeted communities.
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The constitutional rights of 'benefactor children' and 'saviour siblings' to bodily intergrity and autonomy

- Du Plessis, Emma Kate

Authors: Du Plessis, Emma Kate
Date: 2011
Subjects: Children's rights , Civil rights , Genetic engineering
Language: English
Type: Thesis , Masters , LLM
Identifier: vital:10283 , http://hdl.handle.net/10948/d1010420 , Children's rights , Civil rights , Genetic engineering
Description: In modern society, children are acknowledged as bearers of both children‟s rights and all other rights in the Bill of Rights which generally apply to children. One important right, outside of section 28, is that of bodily integrity or the right to control and decide what happens to their body. Therefore, children theoretically have the right to consent to medical treatment and surgery. However, children are generally deemed to lack the necessary maturity to make decisions of this nature and require parental consent before any medical procedure may be performed. Following the enactment of the Children‟s Act 38 of 2005, the age of consent for medical intervention was lowered to the uniform age of twelve. Children above the age of twelve are recognised as having the capacity to make their own decisions in respect of bodily integrity, whereas those under twelve still require parental consent. While this may be a positive evelopment, it is potentially problematic for two groups of children, known as „benefactor children‟ and „saviour siblings‟. In the last 50 years, there has been a noticeable advancement in the field of genetic research. One such development is the possibility of creating one child to save the life of another through tissue or organ donation. This has provided options to parents of children with life threatening conditions where before, there was little hope of a cure. Now, at the request of these parents, children can be specifically “genetically engineered” as an embryo, to become a tissue or organ match to a sick sibling. These children are known as „saviour siblings‟. Another group of children has emerged. While not the result of “genetic engineering”, they serve a similar purpose in being potential life-saving donors to an ill sibling and are known as „benefactor children‟. Both categories of children enjoy the protection of fundamental rights. For those who are under twelve years of age however, the right to bodily integrity can be infringed upon by the proposed surgical removal of organs or tissue for the benefit of a sick sibling, based purely on a parent‟s consent. At stake too, is the right to reproductive autonomy. Parents bear children for a number of different reasons, which can include raising a child to save the life of another. As they have the right to reproductive autonomy, adults are able to decide when they want children and for what reason they want children, which can include the various techniques used to bring about „saviour siblings‟. However, as rights are mutually interrelated and nterdependent, they cannot be viewed in isolation. Therefore, it must be asked: does a person‟s right to reproductive autonomy, as guaranteed by the Constitution, justify interference with an embryo? As an embryo is not recognised in South African law as a legal subject, it will be difficult to justify interference with this right on this basis. The right to consent to medical intervention only from age twelve was described as potentially problematic for „benefactor children‟ and „saviour siblings‟, as parents with seriously ill children may become so emotionally burdened, that they place the welfare of the sick child over that of the healthy child. Thus, it is possible that parents will consent to any and all procedures on the „benefactor child‟ or „saviour sibling‟, regardless of the implications to the health and suffering of the healthy child. Section 28(2) of the Constitution states that the child‟s best interests are of paramount importance but, it must be asked, whose best interests are more important when more than one child is involved? As this is a decision parents are incapable of making at that time, the decision should be made by a neutral, impartial and unemotional third party such as the Court, which can be assisted by the Family Advocate and an ombudsman, who are experts in assisting children and promoting their best interests. Presently, South African law does not expressly address „saviour siblings‟. However, with few changes to the National Health Act and other Regulations, this is an area which could be regulated in time. These changes could include finalising the draft regulations as well as providing a list of the medical and dental purposes for which blood and tissue can be removed and should make specific reference to the removal of tissue, blood or blood products to treat a sick sibling. It is also imperative that South Africa regulates these matters now, as „saviour siblings‟ are no longer simply a matter for the future. Furthermore, legislation needs to be amended and enacted to prevent the law from becoming out-dated and redundant, leaving „benefactor children‟ and „saviour siblings‟ vulnerable while law is being drafted. In that international law is silent on the matter, South Africa would be well advised to consider foreign law such as the United Kingdom, in developing its law. As the United Kingdom has developed a National Board, so too should South Africa, as this would assist in regulating „saviour siblings‟ by allowing members to review each proposed case of „saviour siblings‟. This is merely one recommendation of several which could facilitate a smooth, controlled regulation of a highly emotional topic. Children remain one of the most vulnerable groups in society and their rights are often susceptible to infringement or abuse. It is incumbent on the law to ensure that, wherever possible, these rights are protected, especially as science continues to advance and it becomes more difficult to determine what is morally correct.
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Investigating the effects of performance appraisal in the department of water and sanitation: a study of southern operations regional office

- Adonis Phelisa

Authors: Adonis Phelisa
Date: 2019
Subjects: Employees -- Rating of
Language: English
Type: Thesis , Masters , MA
Identifier: http://hdl.handle.net/10948/40226 , vital:35983
Description: This research examined the use of a personnel performance appraisal, a component of performance management system to evaluate employees at the Southern Operation Region Office of the Department of Water and Sanitation, Port Elizabeth and how this affects their performance. Writers in the available literature, contend that the objective of performance appraisal policy is to review work performance and provide feedback to facilitate measures and programmes to improve employee performance. Cascio and Aginis (2011:73) write that performance appraisal is a systematic description of individual or group job-relevant strengths and weaknesses as an important part of a performance management system. The study firstly analyses the effectiveness of performance appraisal in evaluating the management of the utilisation of resources. Secondly, the appropriateness of the tool in assessing the capacity of employees and contributing towards facilitating programmes and training to develop employee effectiveness. Thirdly, the study also examined the perception of employees on the use of performance appraisal as a management tool in the Department of Water and Sanitation Regional Operation Office. The study adopted a mainly qualitative methodological approach and purposively selected a sample of 30 employees at the Southern Operation Region Office of the Department of Water and Sanitation in Port Elizabeth who completed the questionnaire for the study. The choice of the qualitative research methodology is due to the fact that the approach is well suited to the collection of in-depth and perceptual information and for discovering underlying motivations and perceptions of the employees as respondents. The general employees at the area chosen for the study is one of a relatively young employee profile. The average age of the employees is about 28. The findings revealed that competence, assessment and development, communication and the adequate training which employees received based on the performance appraisal all had an impact on employee performance in Department of Water and Sanitation. Furthermore, factors, such as employee training, competence and communication could not be ignored since they were rated to a moderate extent v by the employees and it also contributed to employee performance. The study findings specifically highlight the importance of effective communication between the employer and the employees in order to improve employee performance appraisal processes. The study recommends a set of guidelines which could be used in improving the current performance appraisal policy and further boost employee performance.
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Title not specified

- Performer not specified, Tracey, Andrew T N

Authors: Performer not specified , Tracey, Andrew T N
Date: 1987
Subjects: Music--European influences , Dance music , Bass guitar , Drum , Organ music , Brass instrument music , Sub-Saharan African music
Language: English
Type: sound recordings , field recordings , sound recording-musical
Identifier: http://hdl.handle.net/10962/107185 , vital:32772
Description: Small dance band song
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The E.coli RNA degradosome analysis of molecular chaperones and enolase

- Burger, Adélle

Authors: Burger, Adélle
Date: 2010
Subjects: Molecular chaperones , Escherichia coli -- Biotechnology , Polyphosphates , Polyphosphates -- Biotechnology , RNA-protein interactions
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:3950 , http://hdl.handle.net/10962/d1004009 , Molecular chaperones , Escherichia coli -- Biotechnology , Polyphosphates , Polyphosphates -- Biotechnology , RNA-protein interactions
Description: Normal mRNA turnover is essential for genetic regulation within cells. The E. coli RNA degradosome, a large multi-component protein complex which originates through specific protein interactions, has been referred to as the “RNA decay machine” and is responsible for mRNA turnover. The degradosome functions to process RNA and its key components have been identified. The scaffold protein is RNase E and it tethers the degradosome to the cytoplasmic membrane. Polynucleotide phosphorylase (PNPase), ATP-dependent RNA helicase (RhlB helicase) and the glycolytic enzyme enolase associate with RNase E to form the degradosome. Polyphosphate kinase associates with the degradosome in substoichiometric amounts, as do the molecular chaperones DnaK and GroEL. The role of DnaK as well as that of enolase in the RNA degradosome is unknown. Very limited research has been conducted on the components of the RNA degradosome under conditions of stress. The aim of this study was to understand the role played by enolase in the assembly of the degradosome under conditions of stress, as well as investigating the protein levels of molecular chaperones under these conditions. The RNA degradosome was successfully purified through its scaffold protein using nickel-affinity chromatography. In vivo studies were performed to investigate the protein levels of DnaK and GroEL present in the degradosome under conditions of heat stress, and whether GroEL could functionally replace DnaK in the degradosome. To investigate the recruitment of enolase to the degradosome under heat stress, a subcellular fractionation was performed to determine the localization of enolase upon heat shock in vivo. The elevated temperature resulted in an increased concentration of enolase in the membrane fraction. To determine whether there is an interaction between enolase and DnaK, enolase activity assays were conducted in vitro. The effect of DnaK on enolase activity was measured upon quantifying DnaK and adding it to the enolase assays. For the first time it was observed that the activity of enolase increased with the addition of substoichiometric amounts of DnaK. This indicates that DnaK may be interacting with the RNA degradosome via enolase.
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Photocatalytic activity and antibacterial properties of Ag/N-doped TiO2 nanoparticles on PVAE-CS nanofibre support

- Ocwelwang, Atsile Rosy

Authors: Ocwelwang, Atsile Rosy
Date: 2012
Subjects: Nanocomposites (Materials) , Nanofibers , Electrospinning
Language: English
Type: Thesis , Masters , MSc (Chemistry)
Identifier: vital:11337 , http://hdl.handle.net/10353/d1006794 , Nanocomposites (Materials) , Nanofibers , Electrospinning
Description: Lack of potable water is one of the major challenges that the world faces currently and the effects of this are mainly experienced by people in developing countries. This has therefore propelled research in advanced oxidation technologies AOTs to improve the current water treatment methods using cost effective, non toxic and efficient treatment methods. Hence, in this study the sol-gel synthesis method was used to prepare TiO2 nanoparticles that were photocatalytically active under UV and visible solar light as well as possessing antibacterial properties. Silver and nitrogen doping was carried out to extend the optical absorption of TiO2. For easy removal and reuse of the photocatalyst the nanoparticles were immobilized on chitosan and poly (vinyl-alcohol-co-ethylene) using the electrospining technique. The synthesized nanomaterials were characterized by FTIR, XRD, SEM/EDS, TEM, DRS, and TGA. FTIR and EDS analysis confirmed the formation and composition of TiO2 nanopowders for the doped and undoped nanoparticles. XRD analysis showed that the anatase phase was the dominant crystalline phase of the synthesized nanopowders. SEM and TEM respectively illustrated the distribution and size of the electrospun nanofibers and the nanoparticles of TiO2. DRS results showed that there was a significant shift in the absorption band edge and wavelength of Ag-TiO2 to 397 nm, followed by N-TiO2 at 396 nm compared to the commercial titania which was at 359 nm. The photocatalytic activities and antibacterial properties of these materials were tested on methylene blue dye and E.coli microorganism respectively. Ag-TiO2 immobilized on nanofibers of chitosan and PVAE had the highest photocatalytic activity compared to N-TiO2. Similar results were observed when the biocide properties of these materials were tested on E. coli.
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The isolation and partial characterization of a2-antiplasmin and plasminogen from ostrich plasma

- Thomas, Adele René

Authors: Thomas, Adele René
Date: 2000
Subjects: Serpins , Ostriches , Antifibrinolytic agents , Plasminogen , Plasmin
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:11080 , http://hdl.handle.net/10948/274 , http://hdl.handle.net/10948/d1005751 , Serpins , Ostriches , Antifibrinolytic agents , Plasminogen , Plasmin
Description: This study reports the isolation, purification and partial characterisation of the ostrich serpin, a2AP, as well as its target enzyme, ostrich plasmin, in its active and inactive proenzyme, viz. plasminogen, forms. Three different procedures were undertaken to isolate and purify ostrich a2AP. The first one involved L-lysine-Sepharose chromatography, ammonium sulfate fractionation, ion-exchange chromatography on Toyopearl Super-Q 650S, and ostrich plasminogen-Sepharose affinity chromatography. The second procedure replaced the latter chromatographic step with gel filtration on Sephadex G-200 and hydroxylapatite chromatography, while the third one employed instead the theoretically more efficient LBSI-Sepharose chromatographic step. The third procedure yielded purified ostrich a2AP, but the degree of purity and yield were relatively low. Ostrich plasminogen was highly purified after L-lysine-Sepharose chromatography and ostrich plasmin was obtained by the urokinase-activation of the purified ostrich plasminogen Ostrich a2AP revealed an Mr of 77-84 K and two isoelectric forms of pI 3.85 and 6.18. Nterminal sequence analysis showed ostrich a2AP to have only 2 out of 11 residues in common with both those of human and bovine a2AP. Ostrich a2AP showed the largest inhibitory effects on ostrich plasmin, followed by comm. bovine chymotrypsin, trypsin and plasmin, in that order, and it appeared to be a much less potent plasmin inhibitor than bovine aprotinin, but a much more potent one than the synthetic inhibitors, DFP and EACA. Ostrich plasminogen showed an Mr of 92 K and multiple isoelectric forms (~7) in the pI range 6.01-9.18, with a major one of pI 6.01. It showed a total of 775 amino acid residues and its N-terminal sequence showed ~53 percent identity with those of human, rabbit, cat, and ox plasminogens. Ostrich plasmin revealed an Mr of 78 K, two isoelectric forms of pI 4.07 and 6.01, and a total of 638 amino acid residues. N-terminal sequence analysis showed that 2-4 residues are identical to the 5 of human, cat, dog, rabbit, and ox plasmins. The pH and temperature optima of ostrich plasmin were determined as 8.0 and 40 oC, respectively. The thermodynamic and kinetic parameters of ostrich plasmin were computed, and plasmin was shown to prefer Lys to Arg residues in the S1 position. In conclusion, ostrich a2AP, plasminogen and plasmin showed definite similarities to their mammalian counterparts, but there were also significant differences.
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Investigations to determine the long-term sustainable yield of the Karoo aquifer and the sustained availability of groundwater for small-scale irrigation projects, in Dendera area, Kwekwe District - Zimbabwe

- Njanike, Joseph Tendayi

Authors: Njanike, Joseph Tendayi
Date: 2001
Subjects: Groundwater , Irrigation -- Equipement and supplies , Irrigation -- Kwekwe (Zimbabwe)
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:5093 , http://hdl.handle.net/10962/d1020853
Description: In this thesis the long-term sustainable yield of the Karoo sediment aquifer unit occurring in Dendera area of Kwekwe District is investigated, with the object of providing quantitative data on the sustained availability of groundwater for small-scale irrigation projects. Archaean Basement Schists and Pre-Cambrian gneissic granites, the Basement Complex rocks, underlie the entire study area. Overlying these are Upper Karoo sediments. Aeolian Kalahari sands unconformably mantle higher interfluves, while redistributed sands occur along valleys of major rivers and streams. The Karoo sediments, which predominantly consist of loosely cemented, fine- to medium-grained sandstone alternating with red siltstone and mudstone, constitute the main aquifer. The thickness of the Karoo sediment unit ranges from 30m to 80m. The hydraulic parameters of the Karoo sediment aquifer were characterised in the field by constant discharge pumping tests and slug tests. Pumping tests indicated unconfined conditions and thus the Neuman's method of analysis has been used. Transmissivities from pumping tests are within the range 4.7 m²/d to 13.6 m²/d with an average of 8.9m²/d. The low transmissivities seem to be a major limiting factor in the exploitation of the groundwater resources. Thus the sustainable borehole yields tend to be small, mean values ranging from 33 m²/d to 253 m²/d. Specific yield could not be determined from the pumping tests due to the lack of observation boreholes. Low chemical concentrations render the water suitable for irrigation of all crops, while neither total nor any individual concentrations present health hazards to human or livestock. An average recharge value of 47.7 mm/y was inferred from water table fluctuation method. Chloride mass balance technique in the same area indicates recharge value in the order of 67.4 mm/y. Because the chloride mass balance gives a long-term mean annual recharge, the recharge figure of 67.4 mm/y was adopted for the study area. Based on the abstractable proportion of recharge, the sustainably exploitable volume of groundwater of the order of 2.68 x 10⁷ m³/y was established. This volume is more than 100 times the estimated current demand for groundwater (1.35 x 10⁵ m³/d), implying that there are large volumes of surplus water, which can be utilised for irrigation.
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Petrogenesis of the upper critical zone in the Western Bushveld Complex with emphasis on the UG1 Footwall and Bastard units

- De Klerk, William Johan

Authors: De Klerk, William Johan
Date: 1992
Subjects: Petrogenesis -- South Africa , Formations (Geology) -- South Africa , Mineralogy -- South Africa , Geochemistry -- South Africa , Petrology -- Africa, Southern , Rustenburg Platinum Mines
Language: English
Type: Thesis , Doctoral , PhD
Identifier: vital:4986 , http://hdl.handle.net/10962/d1005598
Description: This study is an account of the stratigraphic sequence, the petrography, mineralogy (microprobe investigations of orthopyroxene, clinopyroxene, olivine and plagioclase feldspar), and whole-rock major- and traceelement geochemistry of the silicate cumulates of the Upper Critical Zone in the western Bushveld Complex. Two parts of the study - an investigation of a 350m column incorporating the MG3 and UGI Footwall Units, and a comparison of two additional Upper Critical Zone profiles with a previously compiled profile between the UGI and Bastard Units - are focused on RPM Union Section in the northwestern sector of the Complex. The third part is a detailed vertical and lateral investigation of the Bastard Unit at the top of the Critical Zone, which draws on sampling and data compilation from seventeen profiles in the western limb of the Complex. The MG3 Unit (45m) is made up of a lower chromitite layer overlain by a norite-pyroxenite-anorthosite sequence while the UGlFW Unit (295m) is composed of a related series of lower chromitite layers (MG4) overlain by a pyroxenite-norite-anorthosite sequence capped by the UGI chromitite layer. These mafic cumulates display a distinctive pattern of oscillating cryptic variation in whole-rock Mg/(Mg+Fe), FeO/Ti0₂, Cr/Co and Ni/V ratios through the sequence. Sympathetic oscillations are recorded for compositions of orthopyroxene and plagioclase feldspar and eight subcycles are recognised through the UGlFW Unit. The entire sequence is characterised by the presence of small, spheroidal, embayed and irregularly shaped plagioclase grains which are poikilitically enclosed in cumulus orthopyroxene grains of both pyroxenites and norites. This texture is indicative of partial resorption of pre-existing feldspar primocrysts within the melt prior to their being incorporated into the host orthopyroxene grains. Textural, geochemical and isotopic data suggest that this sequence was built up by periodic additions of fresh, relatively primitive liquid into fractionated resident liquid, and subsequent mixing within the magma chamber. The Bastard Unit sequence, described in Chapter 4, is the last and most complete cyclic unit (c. 60m) of the Critical Zone, and its upper contact defines the boundary between the Critical and Main Zones of the Complex. This Unit can conveniently be sub-divided into a lower part, where orthopyroxene occurs as a cumulus phase, and the upper part which is composed entirely of anorthosite (Giant Mottled Anorthosite). The basal part of the Unit (≤ 18m) comprises a thin chromitite layer < O.5cm) overlain by a pyroxenite-melanorite-norite-leuconorite sequence. The basal pyroxenite is orthocumulate in character and rapidly gives way to norites and leuconorites. A distinct threefold subdivision emerges within the Giant Mottled Anorthosite which is predominantly an adcumulate which becomes orthocumulate in character at its top. Apart from minor deviations in thicknesses these lithologies are recorded over the entire strike-length covered in this study. Profiles of cryptic variation are compiled for orthopyroxene, plagioclase and whole-rock data and show that the Bastard Unit displays a characteristic pattern which is maintained throughout the western Bushveld Complex. A minor yet distinctive reversal in cryptic variation is revealed at a level which is stratigraphically variable within the lower Giant Mottled Anorthosite, and results in a double cuspate pattern. A remarkable feature of the basal Bastard pyroxenites is that although the modal proportion of mafic to felsic constituents varies systematically away from the northwestern sector, the Mg/(Mg+Fe) ratio of orthopyroxenes remains constant at 0.804 over a lateral strike distance of 171km. Within the upper part of the Unit the orthopyroxene is markedly Fe-rich and it is here that inverted primary pigeonite appears for the first time as a cumulus phase. In addition, K-feldspar, oscillatory zoned plagioclase grains and high levels of incompatible trace elements are noted at this level. On the basis of the data presented it is concluded that the Bastard Unit represents the crystallisation of a final, relatively large influx of hotter primitive liquid, with upper Critical Zone affinities, and subsequent mixing with a column of cooler (less dense) supernatant liquid which had in part hybridized with the overlying Main Zone magma. It is hypothesised that this new liquid was emplaced as a basal flow beneath supernatant liquid and that it initiated the deposition of mafic cumulates at its base. The supernatant liquid is interpreted as representing the fractionated residuum produced by crystallisation of earlier cyclic units, with plagioclase on the liquidus, and that it contained an abundance of small plagioclase primocrysts in suspension. Development of the Unit can be viewed as a two-stage process. In the lower half of the unit, chemical and physical parameters typical of the new magma dominated the crystallisation process, and resulted in cumulates very similar to other relatively complete Upper Critical Zone units. In the upper, leucocratic sequence, above a minor reversal, crystallisation was from a liquid which was the product of mixing of a minor pulse of primitive liquid with the reservoir of hybridized supernatant liquid. Although the Bastard Unit is not continuous around the entire Western limb of the Complex, it is concluded that it developed in a single, or connected, magma chamber and that its irruptive feeder zone was located in the proximal northwestern facies of the Complex.
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Expanded Public Works Programme as a poverty alleviation strategy in Nyandeni local municipality in South Africa : an experiential study

- Xhongo, Khanya

Authors: Xhongo, Khanya
Date: 2017
Subjects: Public works -- South Africa -- Eastern Cape , Poverty -- South Africa -- Eastern Cape
Language: English
Type: Thesis , Masters , MSoc
Identifier: http://hdl.handle.net/10353/13587 , vital:39682
Description: South Africa is faced by huge societal problem of poverty and unemployment, twenty one years after the dawn of democracy. These societal problems have been addressed by policy interventions such as Expanded Public Works Programme. The programme targets Youth, women and people with disabilities. However it appears that the mainstream of the programme the employment creation through infrastructure does not accommodate all the targets especially the disabled. The study sought to investigate the role played by EPWP in alleviating poverty in Nyandeni Municipality and to find out to what extent it really alleviate poverty. The study took a triangulated research paradigm which used both qualitative and quantitative research approaches to collect data from forty eight respondents, by way of in-depth interviews, focus group discussion and questionnaire survey. The study found out that, inter alia, poverty remains high in Nyandeni Local Municipality, there is rampant empowerment exclusion in the area, the wage rate paid to beneficiaries is too little to pull them out of poverty and the effects of poor exiting strategy are unbearable to beneficiaries as they find it hard to find other means of employment once they exit the programme. Some of the recommendations which the study made in line with improved mainstream empowerment security in relation to EPWP are that ,the government needs to improve the information dissemination about proposed interventions to alleviate poverty and that communities should partner with them to alert them about their needs and what best interventions could impact real change. The government should be mobile and take services to people and there should be consideration to review wage rate. The researcher is quite optimistic that the study will play a part in improving policy implementation.
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