Genetic and biological characterisation of a novel South African Plutella xylostella granulovirus (PlxyGV) isolate
- Authors: Abdulkadir, Fatima
- Date: 2014
- Subjects: Diamondback moth , Diamondback moth -- Control -- South Africa , Plutellidae -- Control -- South Africa , Baculoviruses , Cruciferae -- Diseases and pests -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4113 , http://hdl.handle.net/10962/d1013059
- Description: The diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), is an important pest of cruciferous crops worldwide. The prolonged use of synthetic chemical insecticides as a primary means of control has resulted in the development of resistance in pest populations. In addition, the pest has also evolved resistance to the bacterial insecticidal protein of Bacillus thuringiensis which is also widely used as a method of control. Baculoviruses are considered as effective alternatives to conventional methods of control when incorporated into integrated pest management (IPM) programmes. These viruses target the larval stages of insects, are generally host-specific and are safe for use in the environment. This study aimed to isolate a baculovirus from a laboratory-reared P. xylostella colony, characterise it genetically and then evaluate its virulence against neonate and fourth instar larvae. A laboratory colony of P. xylostella was established using pupae and asymptomatic larvae collected from a cabbage plantation outside Grahamstown in the Eastern Cape province of South Africa. The colony flourished in the laboratory due to prime conditions and availability of food. The duration of development from egg to adult was determined by observation and imaging of the various life stages. The mean developmental time from egg to adult was observed to be 14.59 ± 0.21 days. The population of the insects increased rapidly in number leading to overcrowding of the insect colony, and hence appearance of larvae with viral symptoms. Occlusion bodies (OBs) were extracted from symptomatic larval cadavers and purified by glycerol gradient centrifugation. Analysis of the purified OBs by transmission electron microscopy revealed the presence of a granulovirus which was named PlxyGV-SA. The virus isolate was genetically characterised by restriction endonuclease analysis of the genomic DNA, and PCR amplification and sequencing of selected viral genes. The complete genome sequence of a Japanese P. xylostella granulovirus isolate, PlxyGV-Japan, has been deposited on the GenBank database providing a reference strain for comparison with DNA profiles and selected gene sequences of PlxyGV-SA. BLAST analysis of the granulin gene confirmed the isolation of a novel South African PlxyGV isolate. Comparison of the restriction profiles of PlxyGV-SA with profiles of PlxyGV-Japan and other documented PlxyGV profiles obtained by agarose gel electrophoresis revealed that PlxyGV-SA is a genetically distinct isolate. The data obtained from the sequencing and alignment of ecdysteroid UDP-glucosyltransferase (egt), late expression factor 8 (lef-8) and late expression factor 9 (lef-9) genes with those of PlxyGV-Japan also showed that PlxyGV-SA is a genetically different isolate. In order to determine the biological activity of PlxyGV-SA against neonate and fourth instar P. xylostella larvae, surface dose bioassays were conducted. The median lethal concentration of the virus required to kill 50% (LC₅₀) and 90% (LC₉₀) of the larvae was estimated by feeding insects with a range of doses. In addition, the time to kill 50% of the larvae (LT₅₀) was determined by feeding insects with the LC₉₀ concentration. Larval mortality was monitored daily until pupation. The data obtained from the dose response assays were subjected to probit analysis using Proban statistical software. The time response was determined using GraphPad Prism software (version 6.0). The LC₅₀ and LC₉₀ values for the neonate larvae were 3.56 × 10⁵ and 1.14 × 10⁷ OBs/ml respectively. The LT₅₀ was determined to be 104 hours. The neonate larvae were found to be more susceptible to infection than the fourth instar larvae with the same virus concentration. The concentrations used for the neonate larvae assay did not have a significant effect on the fourth instar as no mortality was recorded. This is the first study to describe a novel South African PlxyGV isolate and the results suggest that PlxyGV-SA has significant potential for development as an effective biopesticide for the control of P. xylostella in the field.
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Relative contribution of wild foods to individual and household food security in the context of increasing vulnerability due to HIV/AIDS and climate variability
- Authors: Abu-Basutu, Keitometsi Ngulube
- Date: 2014
- Subjects: Wild foods -- South Africa -- Eastern Cape , Food security -- South Africa , Food supply -- South Africa , AIDS (Disease) -- Social aspects -- South Africa , HIV infections -- Social aspects -- South Africa , Chronically ill -- South Africa -- Economic conditions , Chronically ill -- South Africa -- Social conditions , Food -- Social aspects -- South Africa , Food -- Economic aspects -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4774 , http://hdl.handle.net/10962/d1010864 , Wild foods -- South Africa -- Eastern Cape , Food security -- South Africa , Food supply -- South Africa , AIDS (Disease) -- Social aspects -- South Africa , HIV infections -- Social aspects -- South Africa , Chronically ill -- South Africa -- Economic conditions , Chronically ill -- South Africa -- Social conditions , Food -- Social aspects -- South Africa , Food -- Economic aspects -- South Africa
- Description: Wild foods are an integral component of the household food basket, yet their quantified contribution to food security relative to other sources in the context of HIV/AIDS, climate change and variability remains underexplored. This study was carried out in Willowvale and Lesseyton which are rural communities in the Eastern Cape province of South Africa. Willowvale is a relatively remote, medium-rainfall coastal community, while Lesseyton is a peri-urban low rainfall inland community. Qualitative and quantitative methods were used to collect data from 78 HIV/AIDS afflicted households with 329 individuals and 87 non-afflicted households with 365 individuals in the two study sites. Households were visited quarterly over 12 months to assess food acquisition methods, dietary intake and quality, and levels of food security, and to determine strategies employed by households to cope with droughts. The wild foods investigated were wild meat, wild birds, wild fish, wild mushrooms, wild leafy vegetables and wild fruits. Diets were moderately well-balanced and limited in variety, with cereal items contributing 52 % to total calorie intake. Mid-upper arm circumference measurements showed that all respondents were adequately nourished. The bulk of the food consumed by households was purchased, with supplementation from own production, wild vegetables and wild fruits. In Willowvale, wild vegetables comprised 46 % of overall vegetable consumption for afflicted households and 32 % for non-afflicted households, while own fruit production comprised 100 % of fruit consumption. In Lesseyton, wild vegetables comprised only 6 % and 4 % of vegetable consumption for afflicted and non-afflicted households, while wild fruit comprised 63 % and 41 % for afflicted and non-afflicted households. More than 80 % of respondents from both afflicted and non-afflicted households had sufficient daily kilocalories, although the majority of afflicted households felt they were food insecure and sometimes collected wild foods as one of their multiple coping strategies. Hunting and gathering of wild foods was associated with site, household affliction status, gender, age and season. More than 80 % of respondents ate wild vegetables and said they were more drought tolerant than conventional vegetables, making them the most consumed wild food and approximately 16 % of respondents ate wild birds, making them the least consumed wild food. Approximately 14 % of respondents from afflicted households in Willowvale sold wild fish, whilst 34 % of respondents from afflicted households and 7 % from non-afflicted households sold wild fruits in Lesseyton. Strategies adopted by households to cope with droughts were different between the two study sites, and households in Willowvale used a wider range of strategies. Given the devastating effects of HIV/AIDS coupled with the drawbacks of climate change and variability on food security, wild foods represent a free and easy way for vulnerable households to obtain food.
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Structural bioinformatics analysis of the Hsp40 and Hsp70 molecular chaperones from humans
- Authors: Adeyemi, Samson Adebowale
- Date: 2014
- Subjects: Structural bioinformatics , Molecular chaperones , Heat shock proteins , Protein-protein interactions , Biomolecules
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4171 , http://hdl.handle.net/10962/d1020962
- Description: HSP70 is one of the most important families of molecular chaperone that regulate the folding and transport of client proteins in an ATP dependent manner. The ATPase activity of HSP70 is stimulated through an interaction with its family of HSP40 co-chaperones. There is evidence to suggest that specific partnerships occur between the different HSP40 and HSP70 isoforms. While some of the residues involved in the interaction are known, many of the residues governing the specificity of HSP40-HSP70 partnerships are not precisely defined. It is not currently possible to predict which HSP40 and HSP70 isoforms will interact. We attempted to use bioinformatics to identify residues involved in the specificity of the interaction between the J domain from HSP40 and the ATPase domain from the HSP70 isoforms from humans. A total of 49 HSP40 and 13 HSP70 sequences from humans were retrieved and used for subsequent analyses. The HSP40 J domains and HSP70 ATPase domains were extracted using python scripts and classified according to the subcellular localization of the proteins using localization prediction programs. Motif analysis was carried out using the full length HSP40 proteins and Multiple Sequence Alignment (MSA) was performed to identify conserved residues that may contribute to the J domain – ATPase domain interactions. Phylogenetic inference of the proteins was also performed in order to study their evolutionary relationship. Homology models of the J domains and ATPase domains were generated. The corresponding models were docked using HADDOCK server in order to analyze possible putative interactions between the partner proteins using the Protein Interactions Calculator (PIC). The level of residue conservation was found to be higher in Type I and II HSP40 than in Type III J proteins. While highly conserved residues on helixes II and III could play critical roles in J domain interactions with corresponding HSP70s, conserved residues on helixes I and IV seemed to be significant in keeping the J domain in its right orientation for functional interactions with HSP70s. Our results also showed that helixes II and III formed the interaction interface for binding to HSP70 ATPase domain as well as the linker residues. Finally, data based docking procedures, such as applied in this study, could be an effective method to investigate protein-protein interactions complex of biomolecules.
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Teachers' perceptions of behavioural problems manifested by Grade 11 and 12 learners in three Namibian schools
- Authors: Akawa, Ester Anna Nelago
- Date: 2014
- Subjects: Education, Secondary -- Namibia School children -- Namibia -- Attitudes Learning disabilities -- Social aspects Behavior disorders in children -- Education (Secondary) -- Namibia Children with social disabilities -- Education (Secondary) -- Namibia Emotional problems of children -- Education (Secondary) -- Namibia Teachers -- Job stress -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1962 , http://hdl.handle.net/10962/d1010868
- Description: In Namibia today few learners with behavioural and learning problems are within special schools as most are placed within the mainstream school system. Placing these learners within the mainstream system is part of the policy of Inclusive Education (IE) because it argues that this would benefit these learners and also save resources. IE is concerned with addressing barriers to learning and behavioural problems are regarded as one of these barriers. IE argues for a series of new approaches to the diagnosis and response to learners with behavioural problems. This poses challenges for teachers in mainstream schools. Teachers are at the forefront of this situation as they are usually the first to observe and experience the behavioural problems in the schools and are expected to respond appropriately. They find this situation both challenging and problematic. This research explores a sample of teachers’ perceptions of learners’ behavioural problems. To collect in-depth information, this study followed a qualitative approach with a case study design. The data were collected through semi-structured interviews, supplemented with observation and document analysis. The study consisted of fifteen respondents: three principals, three teacher counsellors and nine teachers from the three selected schools. This study illuminates the types of behaviour that teachers encounter, the impact of these behaviours, the factors seen as contributing to these behaviours, and how teachers and the school system deal with these behaviours. In addition the study applies Bronfenbrenner’s bioecological model (1992) to explain how the behaviours manifested by Grade 11 and 12 learners, and identified as problematic by teachers, are part of an interconnected nested social system. The results from the study indicate the manifestation of behavioural problems to be common occurrences in secondary schools are evident, amongst others, through fighting, bullying, substance abuse, truancy, and disrespect of teachers and authority. The teachers pointed to the prevalence of these problems as well as the serious impact such problems have on these learners, their fellow learners, and on the teachers. The teachers identified a complex array of what they saw as contributing factors located within the school, peer groups, family and home circumstances, the local community, as well within the national education policy, the economy and society. The study points to some specific, as well as broader, lessons and opportunities for action both for those managing the education system at the national level and for schools and teachers.
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Toward a culture of engagement: leveraging the enterprise social network
- Authors: Alistoun, Garth
- Date: 2014
- Subjects: Communication in organizations -- South Africa Business communication -- South Africa Social media -- South Africa -- Case studies Leadership -- South Africa -- Case studies Human capital -- Management Personnel management Organizational effectiveness
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1154 , http://hdl.handle.net/10962/d1010869
- Description: This research aims to provide a theory of enterprise social networking that generates and/or sustains a culture of employee engagement within a chosen South African private sector company. Based on an extensive review of interesting literature and the application of a grounded theory process in a chosen case, this research work provides a theory of enterprise social networking sustaining and growing employee engagement together with an explanatory theoretical framework that makes the theory more practical. Employee engagement is defined as “the harnessing of organisation member’s selves to their work roles; in engagement people employ and express themselves physically, cognitively, and emotionally during role performances.” This research regards employee engagement as a three part concept composed of a trait (personality/cognitive) aspect, a state (emotional) aspect, and a behavioural aspect. Research has shown that employee engagement has an unequivocal positive impact on business outcomes, such as profitability, business performance, employee retention and productivity. Employee engagement can be regarded as a culture if it is abundant within the organization’s employee population. Gatenby et al. (2009) propose that employee engagement is fostered by creating the desire and opportunity for employees to connect with colleagues, managers and the wider organisation. This standpoint is supported by Kular et al. (2008) who state that the “key drivers of employee engagement identified include communication, opportunities for employees to feed their views upward and thinking that their managers are committed to the organisation.” Further indicators of employee engagement include strong leadership (particularly in the form of servant leadership), accountability, a positive and open organisational culture, autonomy, and opportunities for development. One of the key facets of employee engagement is connection. A complementary definition of social media, an umbrella under which enterprise social networks fall, is that “(it) is more of a relationship channel, a connection channel. Each and every tweet, update, video, post, is a connection point to another human being. And it’s the other human being who will determine your worth to them.” Social media provides participants with access to a larger pool of resources and relationships than they would normally have access to. This enlarged relationship/resource pool is a result of expanding human and social capital enabled through social media tools. In order to produce a theory of enterprise social networking sustaining and growing a culture of employee engagement a rigorous grounded theory methodology coupled with a case study methodology was applied. The case study methodology was used to identify a suitable research site and interesting participants within the site while the grounded theory process was used to produce both qualitative and quantitative data sets in a suitability rigorous fashion. The corroborative data was then used to discover and define the emergent theory.
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The origin of endorheic pans on the African erosion surface North of Grahamstown, South Africa
- Authors: Alistoun, Judith Robyn
- Date: 2014
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4775 , http://hdl.handle.net/10962/d1011048
- Description: Pans on the African Erosion Surface near Grahamstown are small features, which, perhaps due to their small size have been neglected by researchers. From the outset the striking difference of these pans relative to other pans in southern Africa, is that the host rock is silcrete, a highly resistant rock well known as being associated with deeply weathered plateaus. The dominant origin theory for pans in southern Africa was developed by Goudie and Thomas (1985), and focuses on mechanisms relating to erosion and deflation. This model does not fit in well with the pans that have formed on substrate that has largely been unaffected by erosion in recent geological history (thousands to 10 000 years). As such this study examined the role of prolonged chemical weathering of Dwyka Tillite, that has led to the formation of silcrete. The hypothesis was that such deep weathering is responsible for local scale volume changes, which have in turn led to the formation of a depression. The centre of the pan indicated the highest concentration of Al₂O₃ and kaolinite at mid depths, and their concentrations decreased vertically away from these depths, and laterally towards the margins of the pan. Similar results were noted for SiO₂, while CaO and MgO (and calcite and dolomite) were highest at mid depths along the margins of the pan, and decreased laterally toward the centre of the pan. Results indicated that there was a positive relationship in the centre of the pan between: - the degree of chemical weathering and volume losses, - relative elevation of the pan and volume changes. Geochemically and mineralogically, there was a link between the high concentrations of Ca and Mg carbonates and volume gains in the margin of the pans. It is proposed that transpiration of vegetation along the margin of the pan caused the lateral movement of solutes, and the selective exclusion of these solutes by plants was associated with carbonate precipitation, leading to the creation of local relief. These results provide evidence to suggest that weathering and precipitation processes occurring over geological time scales are responsible for minor scale relief features, whose origin has been mistakenly attributed to deflation processes occurring over hundreds to thousands of years.
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An investigation of the intention to leave or stay of health care professionals at St. Andrews Hospital
- Authors: Amanambu, Rochelle Aneeta
- Date: 2014
- Subjects: Medical personnel -- Job satisfaction -- South Africa -- Eastern Cape -- Case studies Medical personnel -- Job stress -- South Africa -- Eastern Cape -- Case studies Hospitals -- South Africa -- Eastern Cape -- Administration Hospitals -- Medical staff -- South Africa -- Eastern Cape Hospitals -- Officials and employees -- South Africa -- Eastern Cape -- Turnover Health services administration -- South Africa -- Eastern Cape Health planning -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:823 , http://hdl.handle.net/10962/d1011091
- Description: Background: The demand for and retention of talent worldwide is aggravated by revolutionary trends that include global competition, demographic changes and technological advances. In South Africa this phenomenon according to Frost (2002) is further challenged by the emigration of skilled people; the relative scarcity of specialist and managerial employees; employment equity and affirmative action procedures. But the development of strategies first requires an understanding of the factors which influence decisions to leave or stay particularly in rural and remote areas. St. Andrews Hospital is a rural district hospital in Ugu District, KZN. Its remoteness from urban areas and the lack of resources contributes towards challenges of attracting and retaining health care professionals to the area. It is the aim of this study to identify the ten most prevalent turnover and retention factors in a rural district hospital with the intention of making recommendations towards strategies to mitigate turnover and improve retention of health care professionals. This study will not only serve the local Human Resource Department but may also be used to inform district and provincial policies as well as departments’ decisions in the design or the review of current retention strategies aimed at reducing turnover. Method: The survey method was used to collect the primary data by distribution of self-administered questionnaires to Health Care Professionals at St. Andrews Hospital. Of the one hundred and fifty questionnaires distributed, one hundred and seven were returned (71% response rate) and formed the basis of the study. Results: Based on the impact scores, the top three turnover factors identified were, the way the organisation is led by top management (0.934); the size of the workload (0.862); and the way problems are dealt with by managers in the organisation (0.817). No statistically significant relationships were found between turnover factors and biographical variable. Availability of quality health services was ranked as the external factor that had the highest influence (78%) on turnover, while geographical location was ranked the lowest. The main reason given by respondents for leaving their previous employment was promotion, followed by distance and personal/family reasons. The top three retention factors identified from the impact scores were the quality of relationships with colleagues (1.698); the amount of support received from managers and colleagues (1.484); and the level of engagement and involvement with the job (1.390). This demonstrates that the salary package often thought to be a first priority factor Mobley, Horner and Hollingsworth (1978); Mobley (1982) and Herzberg (2003) is far less of a determining factor at St. Andrews Hospital than management support, job involvement and person-organisation fit as well as the social relationships formed in the workplace. A positive relationship was found between leadership and job dimension factors at the 1% level of significance. This supports the strong social bond (person-organisation fit) formed in the work environment between management and colleagues that supports retention and increases level of commitment. An important result of the study was that 46% of the respondents were thinking of leaving the town within the year while 29% were considering resigning from St. Andrews Hospital within the year. Conclusion: The results reveal a complex interaction of factors impacting on turnover and retention. The Human Resource Management function has a pivotal role to play in improving its ability to attract and retain professionals through developing comprehensive strategies based on external and internal and environmental factors. The study conveys to the St. Andrews Hospital management that turnover and retention factors are unique to the location and the working environment and differs amongst Health Care Professionals – this should be deliberated on when formulating Hospital Human Resource retention policies.
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Voting and meaning in Hooggenoeg, Grahamstown : an audience's reception of Grocott's Mail's 2011 municipal election coverage
- Authors: Amzat, Ajibola Taofeek
- Date: 2014
- Subjects: Grocott's Mail (Grahamstown, South Africa) Local elections -- South Africa -- Grahamstown Elections -- South Africa Press and politics -- South Africa -- Grahamstown Journalism -- Objectivity -- South Africa -- Grahamstown Newspapers -- Objectivity Journalism -- Political aspects
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:5970 , http://hdl.handle.net/10962/d1011729
- Description: This thesis examines the meanings that residents of the township of Hooggenoeg (in Grahamstown, in the Eastern Cape province of South Africa) made of the election coverage in the Grocott’s Mail newspaper during 2011 municipal elections in South Africa. In addition, this study also sought to understand the particular set of ‘normative roles’ played by the paper, both with reference to the well-established body of theory about the normative roles of journalism in a democracy, and in terms of the paper’s own conceptualisation of its role in the functioning of local democracy. Grocott’s Mail, the oldest independent newspaper in South Africa, provided extensive pre-election coverage, which included producing and distributing an unprecedented free edition of the paper. The paper also facilitated a town hall debate in order to encourage residents to vote, and empower them to make a more informed choice about their vote. Three qualitative research methods, namely qualitative content analysis, focus group interviews, and individual interviews were used to examine the relationship between the content provided by the paper and the audience’s process of ‘making sense’ and deriving meaning from the content provided. The study concludes that Grocott’s attempt to encourage democratic culture in Grahamstown, in keeping with the more ‘facilitative’ normative roles that the local media can play, was only partially successful. Much of the election reporting subordinated the voices of the ordinary people, and privileged reporting that focussed narrowly on the voting process, and which foregrounded the views of political parties. Overall this coverage largely failed to resonate with the Grocott’s readers who live in Hooggenoeg (a largely ‘coloured’ area of Grahamstown), whose key concerns in terms of their daily life – such as poverty, unemployment, crime, lack of services – seemed, to them, unaddressed by this election coverage and, consequently, was not as engaging or convincing as the publishers/editors had hoped it would be. It can be also argued that Grocott’s narrow conceptualisation of democracy as entailing only public participation in electoral processes failed to cater for how audiences can be made aware of how they can participate in governance beyond the election period.
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Distribution of heavy minerals sand in Namalope deposit, Moma district, Mozambique
- Authors: Assane, Ali Ossufo
- Date: 2014
- Subjects: Heavy minerals -- Mozambique -- Moma District , Prospecting -- Mozambique -- Moma District , Mines and mineral resources -- Mozambique -- Moma District , Ilmenite -- Research , Zircon -- Research , Rutile -- Research
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5056 , http://hdl.handle.net/10962/d1012169 , Heavy minerals -- Mozambique -- Moma District , Prospecting -- Mozambique -- Moma District , Mines and mineral resources -- Mozambique -- Moma District , Ilmenite -- Research , Zircon -- Research , Rutile -- Research
- Description: The spatial distribution of heavy minerals along the mine paths 2014 and 2015 at the wet concentrate plant B shows an increase of heavy minerals sand concentration northwards and slime contents southwards, and it is commonly associated with depth and grain sorting; the increase of heavy minerals concentration with depth is considered to be from the surface formed by Unit 6 to the bottom of Unit 7. The Unit 82 is characterized by low heavy minerals concentrations and high slime contents declining northwards. The mineral proportion estimation suggests that ilmenite is the most abundant heavy mineral in the entire area followed by zircon, rutile and mozanite, and some accessory minerals such as chromite, kyanite, staurolite, tourmaline, epidote, spinel and quartz. The ilmenite occurrence is divided into ilmenite low (< 53% TiO₂) and high (> 53% TiO₂); the ilmenite high with zircon and rutile shows tendency to increase northwards while ilmenite low increase southwards. Zircon, monazite, rutile, chromite, kyanite and staurolite show low variability, which is probably associated with high resistance of minerals for abrasion during transportation and diagenesis. The depositional model of the Namalope deposit, in the flat area and wet concentrate plant B in particular, suggests deposition in a shallow marine environment associated with regression for deposition of Unit 6, 7 and 9 and transgression during deposition of Unit 82. The spatial distribution of heavy minerals in the Namalope deposit and its environment of deposition are the key points for discovery of new deposits around the Namalope with the same characteristic of mineral assemblage and they are used for mine strategic plans such as update block model and mine design.
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Effect of diet and sex-sorting on growth and gonad development in farmed South African abalone, Haliotis midae
- Authors: Ayres, Devin William Philip
- Date: 2014
- Subjects: Haliotis midae -- South Africa , Haliotis midae fisheries -- South Africa , Abalone culture -- South Africa , Abalones -- Physiology -- South Africa , Abalones -- South Africa -- Growth , Abalones -- Feeding and feeds -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5357 , http://hdl.handle.net/10962/d1010856 , Haliotis midae -- South Africa , Haliotis midae fisheries -- South Africa , Abalone culture -- South Africa , Abalones -- Physiology -- South Africa , Abalones -- South Africa -- Growth , Abalones -- Feeding and feeds -- South Africa
- Description: Abalone, Haliotis midae, farmers in South Africa that feed formulated diets reported a periodic drop in abalone growth during periods of increased gonad development. A large drop in abalone biomass was noticed after presumed spawning events. This study was aimed to determine the effect of diet and sex-sorting on gonad development in abalone. Experiments were conducted on a commercial abalone farm from July 2012 to the end of June 2013. Isonitrogenous and isoenergetic diets were formulated with two protein sources. A fishmeal and soybean meal (S-diet) diet and a fishmeal only (F-diet) diet were fed to abalone (50 - 70 g abalone⁻¹) over 12 months. Weight and length gain, gonad bulk index (GBI), visceral index (%) and meat mass index (%) were determined monthly and seasonally. A histological study on the female gonads was conducted. This study also included an experiment to test the effect of sex-sorting (70 - 80 g abalone⁻¹) on growth and body composition with treatments including males (M), females (F) and equal numbers of males and females (MF). Weight gain and length gain were faster in S-diet-fed abalone (RM-ANOVA, F ₍₁, ₁₆₎ = 7.77, p = 0.01; F ₍₁, ₆₉₎ = 49.9, p < 0.001, respectively). Gonad development was significantly affected by the inclusion of soybean meal with S-diet-fed abalone showing higher GBI-values than F-diet-fed abalone (RM-ANOVA, F ₍₁, ₃₃)= 16.22, p = 0.0003). Male abalone had higher GBI-values than females (RM-ANOVA, F ₍₁, ₃₃₎ = 39.87, p < 0.0001). There was no significant difference in average feed conversion ratio (FCR) between diets over time (RM-ANOVA, F ₍₁, ₂₁₎ = 0.008, p = 0.97). However, average FCR-values were significantly highest between November 2012 and March 2013, the presumed spawning season. The visceral mass (gut and gonad) as a proportion of whole mass (visceral index, %) was significantly higher in abalone fed the S-diet (RM-ANOVA; F ₍₁, ₆₉₎ = 68.06, p < 0.0001). There was no difference in meat mass index (%) between diets for both male and female abalone (RM-ANOVA; F ₍₇, ₂₄₈₎ = 0.80, p = 0.60; F ₍₇, ₂₄₁₎ = 1.7, p = 0.11,respectively). Meat mass index significantly decreased from September 2012 to February 2013 coinciding with the period of high GBI-values. The distribution of oocyte maturity stages differed between diets. The majority of oocytes within S-diet-fed abalone were fully mature stage 8 oocytes compared to a majority of stage 7 oocytes in F-diet-fed abalone. Histology corroborated peaks in GBI-values for abalone fed both diets. There was no significant difference in growth, GBI, visceral index (%) and meat mass index (%) between abalone sorted into monosex and mixed-sex populations. Thus, the presence of the opposite sex did not have an effect on growth and gonad mass in H. midae. The phytoestrogens daidzin, glycitin, genistin, daidzein, glycitein and genistein were present in soybean meal and only traceable amounts were found in the F-diet. This study provided evidence that soybean meal present in formulated feed affected growth and gonad development in H.midae. The difference in the distribution of the maturity stages of oocytes was affected by diet. Sex-sorting abalone into monosex and mixed-sex populations had no influence on weight and length gain and gonad development.
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A needs-ICTD strategy alignment framework foundation for the measurement of ICTD impact
- Authors: Baduza, Gugulethu Qhawekazi
- Date: 2014
- Subjects: Siyakhula Living Lab SAP Research Needs assessment -- Information technology -- Social aspects -- South Africa -- Case studies Information technology -- South Africa -- Management -- Case studies Information technology -- Social aspects -- South Africa Rural development -- Economic aspects -- South Africa Rural development -- South Africa -- Sociological aspects Rural development projects -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1155 , http://hdl.handle.net/10962/d1011116
- Description: Many Information and Communication Technologies for Development (ICTD) projects are established with the overall aim of positively developing the communities they are implemented in. However, the solutions that are provided are often commonly developed without the needs of these communities being sufficiently investigated beforehand. As a result the ICTD strategy of the project ends up not well aligned with the aims and targets of the needs of the community. As a result of this, an appropriate programme theory for the project and relevant impact indicators fail to be adequately developed. Consequently, when an impact assessment is conducted it is often found that the intended effects are not directly linked to the needs of the community or what the community had hoped to gain from the ICTD initiative. The purpose of this research serves to develop a needs-ICTD strategy alignment foundation that supports the identification and formulation of impact assessment indicators. Through this research, a framework is developed to support the alignment of ICTD strategy, the development and the promotion of contextual needs of rural communities and other frequently marginalized areas. The Needs-ICTD strategy alignment framework is composed of eight main components that describe the process that can be used to align ICTD strategy with community needs. These components include: collaboration between the internal and external stakeholders, the development of the community, conducting baseline studies, the needs assessment, the ICTD strategy, linking of the needs-ICTD strategy, and lastly the identification of impact indicators. An interpretive research approach is used to explore and inform the framework through a multi-case study investigation of the Siyakhula Living Lab and two projects in the Systems Application Products (SAP) Living Lab. Two main case study questions drive the exploration of the framework, that being: 1) How are the needs of the community elicited and how is the ICTD strategy aligned to the needs of the community? 2) And, why were the selected approaches chosen for aligning the needs of the community and ICTD strategy? Data for this research was collected qualitatively through interviews, document analysis and participant observation. Key findings indicate that the involvement of internal (local) stakeholders in the development and alignment of ICTD strategy to the needs of the community is still lacking. As a consequence, many community members end up not fully understanding the project objectives and how these objectives aims are to be achieved. The research also finds that ‘solution specific’ projects also fail communities as they focus specifically on one target group and repeatedly fail to assist the community holistically in supporting their information and their community development needs.
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My grandmother breaks her hip
- Authors: Bamjee, Saaleha
- Date: 2014
- Subjects: Creative writing (Higher education) -- Research -- South Africa , Creative writing -- Poetry , South African poetry (English) -- Study and teaching (Higher) , South African poetry (English) -- 21st century , English language -- Writing
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:5998 , http://hdl.handle.net/10962/d1020881
- Description: A collection of narrative and confessional poems. The poems are mostly short, cinematic, physical, imagistic: moments in time. They explore the poet’s own life, body, memories, and family relationships, and the tensions between power, duty, love and faith. Several poems concern the navigation of meaning and belonging in a time when international urban culture often clashes with tradition.
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An exploration of the way in which values and valuing processes might strengthen social learning in water stewardship practices in South Africa
- Authors: Barnes, Garth
- Date: 2014
- Subjects: Integrated water development -- South Africa -- Case studies , Water conservation -- South Africa -- Case studies , Water-supply -- Moral and ethical aspects -- South Africa , Environmental education -- South Africa , Social learning -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1975 , http://hdl.handle.net/10962/d1012940
- Description: This qualitative study, focussing on the way in which values and valuing processes might strengthen social learning in water stewardship practices in South Africa, is located within the broader global narrative that describes the scale of human impact on our Earth systems and that is setting humanity on a trajectory that threatens to place us beyond the safe operating spaces called planetary boundaries. For humanity to live within planetary boundaries – one of which is global freshwater use –will take a new way of relating to the environment called Earth stewardship, which calls for a new ethic of responsibility towards Earth systems. It is at the local level of stewardship within a global approach to water resources management called integrated water resources management that this qualitative study is contextually bound. Two case studies, located in the catchment management forums (CMFs) of the Upper Vaal catchment of Gauteng, South Africa, are used in an exploration of the way in which values and valuing processes might strengthen social learning in water stewardship practices in South Africa. The meta-theory of critical realism is used to help explore this relationship between values, practice and social learning. The study uses document analysis, interviews and observation of selected water stewardship practices to identify held and assigned values, and valuing processes and their influence on social learning, and the framing and de-framing processes that occur in social learning oriented towards water stewardship practices. The study differentiates between held and assigned values and identifies a strong altruistic-held values tendency that characterises forum participants who practice water stewardship in the two case study sites. Most water stewardship practice, identified in the case study sites, manifests as compliance activities in the public – or forum – space, while private-sphere environmentalism is mostly left to the confines of the individual’s private household. Lastly, the CMFs seem to have the potential to provide a space for social learning that is not yet maximised. Drawing from these key findings, the study’s major recommendation is that forums that facilitate learning, either using the current CMF structure or creating new opportunities, need to be provided as a conduit for social learning and reflexivity to make the existing boundaries between private and public forms of water stewardship more porous. This social learning may expand social practice and thus strengthen social change processes that expand water stewardship practices.
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Invariant optimal control on the three-dimensional semi-Euclidean group: control affine and quadratic Hamilton-Poisson systems
- Authors: Barrett, Dennis Ian
- Date: 2014
- Subjects: Automorphisms , Symmetry (Mathematics) , Lyapunov stability , Geometry, Riemannian , Geometry, Affine , Elliptic functions
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/64805 , vital:28605
- Description: In this thesis we consider invariant control systems and Hamilton-Poisson systems on the three dimensional semi-Euclidean group SE(1,1). We first classify the left-invariant control affine systems (under detached feedback equivalence). We provide a complete list of normal forms, as well as classifying conditions. As a corollary to this classification, we derive controllability criteria for control affine systems on SE(1,1). Secondly, we consider quadratic Hamilton-Poisson systems on the (minus) Lie-Poisson space se(1,1)*. These systems are classified up to an affine isomorphism. Six normal forms are identified for the homogeneous case, whereas sixteen representatives (including several infinite families) are obtained for the inhomogeneous systems. Thereafter we consider the stability and integration of the normal forms obtained. For all homogeneous systems, and a subclass of inhomogeneous systems, we perform a complete stability analysis and derive explicit expressions for all integral curves. (The extremal controls of a large class of optimal control problems on SE(1,1) are linearly related to these integral curves.) Lastly, we discuss the Riemannian and sub-Riemannian problems. The (left-invariant) Riemannian and sub-Riemannian structures on SE(1,1) are classified, up to isometric group automorphisms and scaling. Explicit expressions for the geodesics of the normalised structures are found.
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The epibiotic relationship between mussels and barnacles
- Authors: Bell, Caroline Margaret
- Date: 2014
- Subjects: Epibiosis , Mussels -- Ecology -- South Africa , Mussels -- Behavior -- South Africa , Mussels -- Habitat -- South Africa , Barnacles -- Ecology -- South Africa , Barnacles -- Behavior -- South Africa , Barnacles -- Habitat -- South Africa , Perna -- Behavior -- South Africa , Mytilus galloprovincialis -- Behavior -- South Africa , Marine biodiversity -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5847 , http://hdl.handle.net/10962/d1011460 , Epibiosis , Mussels -- Ecology -- South Africa , Mussels -- Behavior -- South Africa , Mussels -- Habitat -- South Africa , Barnacles -- Ecology -- South Africa , Barnacles -- Behavior -- South Africa , Barnacles -- Habitat -- South Africa , Perna -- Behavior -- South Africa , Mytilus galloprovincialis -- Behavior -- South Africa , Marine biodiversity -- South Africa
- Description: Epibiosis is an ecological relationship that has been described as one of the closest possible associations in marine ecosystems. In the space limited rocky intertidal, mussel beds provide important secondary space for barnacles. The epibiotic relationship between mussels and barnacles on the south-east coast of South Africa was considered at different scales, from large-scale, natural patterns of epibiosis on the rocky shore, to fine-scale settlement choices of barnacles and the effects on the condition and growth rates of individual mussels. Mussel and barnacle assemblages were generally stable over a 12-month period. The tracking of individual mussels with and without barnacle epibionts resulted in a significant increase in mortality rate of mussels with epibionts over 12 months (two-way ANOVA, p = 0.028). Barnacles on rocks, as well as on mussels, were also tracked with no significant effect of substratum on mortality of barnacles (two-way ANOVA, p = 0.119). Prevalence and intensity of barnacle infestations was also examined in relation to coastline topography on two co-occurring mussel species, the indigenous Perna perna and invasive Mytilus galloprovincialis. The results were complex, but bay status had significant effects on prevalence and intensity for both mussel species, depending on the time and zone. The effect of bay in relation to time was particularly relevant for M. galloprovincialis (four-way nested ANOVA, Season X Site(Bay): p = 0.0002), where summer prevalence was higher than that of winter in bays, regardless of zone, while in open coast sites, the effect of season was only significant in the mid zone. Patterns of intensity generally showed higher values in summer. Substratum preference by barnacles was investigated by recording settlement, survival and mortality of Chthamalus dentatus barnacles on various treatments. There was a strong preference for the rock-like plastic substratum by primary settlers (pair-wise tests of PERMANOVA: Dead < Rock mimic (p = 0.0001); Replica < Rock mimic (p = 0.019) and Live < Rock mimic (p = 0.0001)). This indicates that barnacles settle on mussel shells only as a secondary choice and that micro-topography is an important variable in barnacle settlement. The effect of barnacle epibiosis on condition index and growth of P. perna and M. galloprovincialis was also examined as a direct indication of the health of mussels subjected to the biological stress of epibiosis. Although not significant (PERMANOVA: P. perna: p(perm) = 0.890; M. galloprovincialis: p(perm) = 0.395), growth for both mussel species was slower for barnacle-infested individuals in summer, which is the main growing season for mussels in the region. Results from condition index calculations, however, showed no negative impacts of epibiotic barnacles (three-way ANCOVA: P. perna: p = 0.372; M. galloprovincialis: p = 0.762). Barnacle epibionts create a new interface between the mussel and its environment and this interaction can affect other members of the community. The possibility of the barnacle epibiont causing increased drag also needs further investigation. Biological processes operating within a wide range of physical stressors drive the interactions on the rocky shore, such as epibiosis. Overall, the results of this study suggest that the epibiotic relationship between mussels and barnacles on the south-east coast of South Africa does not significantly affect the mussel species present and that barnacles only use mussel shells as a secondary choice of substratum.
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How to open the door
- Authors: Beyers, Marike
- Date: 2014
- Subjects: Creative writing (Higher education) -- Research -- South Africa Creative writing -- Poetry South African poetry (English) -- Study and teaching (Higher) South African poetry (English) -- 21st century English language -- Writing
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:5969 , http://hdl.handle.net/10962/d1011502
- Description: A collection of mostly lyrical poems. The poems explore moments of experience and thought relating to longing and belonging, in terms of relations, memory and place. The poems are mostly short and intense. Silence and implied meanings are often as important as what is said; shadows are evoked to recall substance. Though short, the poems are not tightly closed – on the contrary, meanings proliferate in the process of exploration
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The effects of age on the worker capacity and mechanisation on the task demands in a South African manufacturing industry
- Authors: Bezuidenhout, Samantha Catherine
- Date: 2014
- Subjects: Age and employment -- South Africa , Labor -- Social aspects -- South Africa , Brickmaking -- South Africa -- Automation , Brickmaking -- Social aspects -- South Africa , Brick trade -- South Africa , Aging -- Social aspects -- South Africa , Aging -- Research
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5151 , http://hdl.handle.net/10962/d1013167
- Description: The focus of the study was two-fold, firstly to determine the effect of age on the capacity of manual materials handling workers and secondly to determine the effect of increasing task mechanisation on the workers’ responses to task demands. The first component of this study, namely Part I, 101 male and 12 female ‘unskilled’ manual workers – of various ages – from a brick manufacturing industry were assessed. Anthropometric, health and strength factors were measured to improve the understanding of the South African manual worker capacity and more specifically, the effect of age on this capacity. Data collection was done between 7.30am and 9.30am in a laboratory-type setting on-site. Anthropometric characteristics (including body mass index, waist to hip ratio, waist circumference and body fat percentage) provided information on the state of obesity and the impact of age in the South African context. Linked to this, the health factors (including blood pressure, resting heart rate and a self-reported questionnaire) provide an extra snapshot of the disease profile in South Africa, and could potentially influence other capacity factors. Isometric strength capacities (of eight different areas, namely: back, leg, bicep, shoulder, pinch, pinch and pull) demonstrated whether South African manual workers show the same decline in strength with aging as seen in industrially advanced countries. The second component of the study, Part II, was performed in situ and measured the workers’ responses to task demands of three brick palletising tasks, one manual (n=21) and two with increasing mechanisation (n=12 each). Spinal kinematics, joint forces and working heart rate were assessed on normal work days during a 30-lift duration and body discomfort measures were taken at the start, middle and end of the work-shift. Spinal kinematics were measured dynamically using a lumbar motion monitor, whereas the spinal forces were estimated using the three dimensional static strength prediction program. The worker capacity results showed that waist to hip ratio, waist circumference and body fat percentage increased significantly with aging, whereas body mass index was not affected by age. All body morphology values were within ‘normal’ ranges. Although diastolic blood pressure increased significantly with age, systolic was not affected significantly by age. Both groups, however, showed an increasing prevalence of hypertension with aging. There were no significant changes in resting heart rate with aging, with a range of 66 bt.min⁻¹ to 74.86 bt.min⁻¹, therefore within normal ranges. Of the strength factors, age only affected shoulder and push strength significantly: Showing a decrease in shoulder strength from 49.89 kgF to 39.91 kgF in the men aged 20-29 to the 50-59 respectively and an increase in push strength from men aged 30-39 and 40-49 to those aged 50-59. Part II results revealed highly frequent lift rates and large degrees of sagittal flexion and lateral bending in all three tasks. These postures adopted for long durations are likely to lead to the development of musculoskeletal disorders. Heart rates of workers from the three tasks were significantly different and heart rates for two tasks were above the recommended 110 bt.min⁻¹. Similarly the body discomfort ratings of the three tasks differed, although a common trend was seen in that lower back pain was the most commonly reported area of discomfort in all tasks. South African manual materials handling males did not show the same responses to aging as men from industrially advanced countries, calling for further research into these differences. Due to the high risks of the three tasks assessed, future research and interventions are required to reduce the risk of injury in the assessed tasks.
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Grieving forests
- Authors: Bila, Freddy Vonani
- Date: 2014
- Subjects: Creative writing (Higher education) -- Research -- South Africa , Creative writing -- Poetry , South African poetry (English) -- Study and teaching (Higher) , South African poetry (English) -- 21st century , English language -- Writing
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:5997 , http://hdl.handle.net/10962/d1020880
- Description: This is a collection of village narrative poems mainly set in rural Limpopo that searches into the complexity of the past and how historical events impact on the present. Although the poems are imagined along the Marxist dialectic, they’re fresh imaginative creations featuring a strong element of surprise, spiritual mysticism, experimenting with form, delving into unknown poetic avenues, creating new music, exploring new sounds and taking risks. The long and intense poem, Ancestral wealth, which is a tribute to the poet’s father, reflects on death and its impact through the effective application of various stylistic elements and poetic devices, thus immortalising the life of a rural South African. Overall the poems, including retrospective and experimental ones, condemn the free market economic system and all that it seems to necessitate: the degradation of ecology, indifference to human suffering and the alienation of vulnerable social groups.
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Age, growth, reproduction and sexual dimorphism of the striped dolphin, Stenella coeruleoalba, off the south-east coast of southern Africa
- Authors: Bishop, Amy Ruth
- Date: 2014
- Subjects: Striped dolphin -- Conservation -- Africa, Southern , Striped dolphin -- Development -- Africa, Southern , Striped dolphin -- Africa, Southern -- Reproduction , Striped dolphin -- Age determination -- Africa, Southern , Dolphins -- Conservation -- Africa, Southern , Dolphins -- Development -- Africa, Southern , Dolphins -- Africa, Southern -- Reproduction , Dolphins -- Age determination -- Africa, Southern , Dimorphism (Animals)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5848 , http://hdl.handle.net/10962/d1011600 , Striped dolphin -- Conservation -- Africa, Southern , Striped dolphin -- Development -- Africa, Southern , Striped dolphin -- Africa, Southern -- Reproduction , Striped dolphin -- Age determination -- Africa, Southern , Dolphins -- Conservation -- Africa, Southern , Dolphins -- Development -- Africa, Southern , Dolphins -- Africa, Southern -- Reproduction , Dolphins -- Age determination -- Africa, Southern , Dimorphism (Animals)
- Description: The striped dolphin, Stenella coeruleoalba, is an oceanic dolphin found worldwide in tropical to warm temperate waters. Globally populations are threatened through direct fishing, bycatch and pollution. Little is known about the life history of this species in South African waters and it is currently listed as ‘Data Deficient’ by the International Union for Conservation of Nature (IUCN). Critical to the conservation and management of this species is an understanding of basic life history parameters. For the present study, metadata and tissues from 101 stranded S. coeruleoalba along the south-east coast of southern Africa between 1969 and 2012 were analyzed to examine age and growth, male and female reproduction and sexual dimorphism. Age and growth were determined by counting the number of growth layer groups (GLG’s) present in their teeth. A von Bertalanffy growth curve gave the best fit to the data and indicated that physical maturity was reached around 21 years in males and 18 years in females. Additionally, asymptotic lengths were reached at 231cm and 224cm in males and females, respectively. The maximum ages obtained were 21 years for males and 20 years for females. Length at birth was estimated to be between 116cm and 119cm for males and between 112cm and 114cm for females. The reproductive status of the adult dolphins was assessed by histological and macroscopic analyses of gonadal tissue. Sexual maturity was attained before physical maturity in both sexes. The males reached sexual maturity between 8 and 12 years of age and between 209 and 224cm in total body length. The maximum combined testis weight comprised about 0.24% of the total body weight and sexual maturity was reached between a combined testis weight of 16 and 41g, a mean testis length of 8 and 10cm, and a mean seminiferous tubule diameter of 44 and 70μm. Females attained sexual maturity between 7 and 8 years of age and between 213 and 216 cm in total body length. The ovulation rate was 0.32 per year and the majority of ovulations occurred in the left ovary, with ovulations occurring in the right ovary only in individuals older than 10 years of age. The annual pregnancy rate was calculated to be 26%. Reproductive seasonality could not be established due to the small sample size and the absence of samples throughout the year. However, both conceptions and births appear to occur in both August and December/January. Additionally, testis weight and seminiferous tubule diameters appear to fluctuate throughout the year, which could suggest reproductive seasonality in this species. Sexual size dimorphism in mature adults was evident for a number of external measurements, however, sexual shape dimorphism was not present in this species. Mature males had significantly longer and wider pectoral fins, dorsal fins and flukes than females (p<0.05 in all cases). It was suggested that the larger appendages are required for male on male combat during intraspecific competition for females. Additionally, larger appendages aid in thermoregulation, propulsion and maneuverability. Females had a significantly greater distance between the tip upper jaw and the genital aperture and anus, which was expected due to differences in anatomy between male and female genital openings. Overall, S. coeruleoalba did not exhibit distinct sexual dimorphism and together with the relatively small testes in relation to the total body weight (0.24%) it was proposed that this species demonstrates a less extreme form of polygyny. Additionaly, the results of this study are important to the understanding of the basic biology of the species.
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Gold mineralization in a high grade metamorphic terrane in the Handeni District, Eastern Tanzania
- Authors: Bitesigirwe, Godfrey Stephen
- Date: 2014
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/54756 , vital:26609
- Description: Most orogenic type gold deposits are formed under low greenschist facies to mid amphibolite facies metamorphic conditions and deposition is either structurally or lithologically controlled. A few known gold deposits found in high grade metamorphic terranes include those in the Yilgarn craton in Australia, Renco in Zimbabwe, Hemlo in Canada and the recently discovered Handeni deposit in Tanzania. Within Tanzania, gold deposits are mainly hosted in Archaean low grade metamorphic rocks commonly known as the Lake Victoria greenstone belt. The greenstone belts of Tanzania are of Nyanzian age (> 2.5Ga) and are located to the south and east of Lake Victoria on the Tanzania craton. The Tanzania Craton is surrounded by Usagaran 1.9 Ga rocks (the east African orogenic belt (EAO) better known as the Mozambique belt) to the east and the Ubendian belt to the south and west. Published reports show that the eastern part of the Tanzania Craton is dominated by the fragments of Archaean rocks. Metamorphism along East Africa and the Tanzania Craton is due to several geological events. These geological events include the intrusion of granites in the Archaean Tanzania Craton (3 Ga), subduction of ocean plate resulted to the formation of Usagaran belt (1.9 Ga), opening and closure of Mozambique Ocean, which resulted in the formation of the Mozambique belt between 700 – 800 Ma and the Pan African orogeny at 640 – 620 Ma, which is associated with the formation of Gondwana. It is believed that fragments from the Archaean Tanzania craton were re - metamorphosed during these events. The Handeni project (the focus of this thesis) is located in the northern portion of the eastern part of the Usagaran belt (1.9 Ga) comprising the eastern part of Archaean Tanzania Craton. The area is characterized by Proterozic rocks of basaltic composition. The documented 2.7 Ga rocks at the Kilindi Handeni Superterrane at the northern part of the Usagaran belt correlate well with 2.7 Ga of Nyanzian rocks of Archaean Tanzania craton. The Handeni project area is geologically dominated by metamorphosed and deformed units of quartzofeldspathic gneisses, migmatitic gneiss, garnet silicified rock, garnetiferous amphibolite, garnetiferous granulite, graphitic schist and hornblende pyroxenite. Intensive deformation features that were developed include folds (sheath folds, micro and macro scales), faults, shears and regional thrusts. This thesis focuses on identifying the protolith of the rocks, alteration minerals, and metamorphic assemblages in the project area in order to understand the timing of gold mineralization. Geological investigation of core, ore petrology and mineralogy, mineral composition by using JEOL microprobe analysis and XRF analysis of bulk rocks were utilized. All the analytical work was done at the Geology laboratory, Rhodes University. Petrographic analysis shows that the rocks sampled in the study area are characterized by alteration minerals such as calcite, dolomite and sericite. Sulphide minerals including chalcopyrite, pyrrhotite, pyrite, pentlandite and gersdorffite were identified. Gold mineralization is associated with disseminated sulphides in association with trace amounts of base metals. Four rock types were proposed as host rocks for the mineralization, namely garnet silicified rock with superimposed quartz veins, garnetiferous amphibolite, garnetiferous granulite and hornblende pyroxenite. Fold troughs, filled fractures associated with episodes of folding, quartz veins and shear zones are suggested as gold precipitation sites. The presence of high grade metamorphic rocks containing gold, intermediate to low grade assemblages with sulphides and associated hydrothermal alteration as well as a complex deformation history suggests that the Handeni mineralization took place over an extended time period stretching from a ductile to a brittle environment.
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