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Quinones and halogenated monoterpenes of algal origin show anti-proliferative effects against breast cancer cells in vitro:

  • Authors: de la Mare, Jo-Anne , Lawson, Jessica C , Chiwakata, Maynard T , Beukes, Denzil R , Blatch, Gregory L , Edkins, Adrienne L
  • Date: 2012
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/165165 , vital:41214 , DOI: 10.1007/s10637-011-9788-0
  • Description: Red and brown algae have been shown to produce a variety of compounds with chemotherapeutic potential. A recent report described the isolation of a range of novel polyhalogenated monoterpene compounds from the red algae Plocamium corallorhiza and Plocamium cornutum collected off the coast of South Africa, together with the previously described tetraprenylquinone, sargaquinoic acid (SQA), from the brown algae Sargassum heterophyllum. In our study, the algal compounds were screened for anti-proliferative activity against metastatic MDA-MB-231 breast cancer cells revealing that a number of compounds displayed anti-cancer activity with IC50 values in the micromolar range. A subset of the compounds was tested for differential toxicity in the MCF-7/MCF12A system and five of these, including sargaquinoic acid, were found to be at least three times more toxic to the breast cancer than the non-malignant cell line.
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  • Date Issued: 2012

Guidelines to establish an e-safety awareness in South Africa

  • Authors: De Lange, Mariska
  • Date: 2012
  • Subjects: Internet and children--Safety measures , Internet in education , Online etiquette
  • Language: English
  • Type: Thesis , Masters , MTech
  • Identifier: vital:9747 , http://hdl.handle.net/10948/d1007863 , Internet and children--Safety measures , Internet in education , Online etiquette
  • Description: Information and Communication Technology (ICT) has become an integral part of almost every individual’s life. Although ICT, particularly the Internet, might offer numerous opportunities, individuals should also be aware of the associated risks. Especially with the younger generations who can be seen as being the most vulnerable to online dangers as they are becoming more involved in online activities. Children are utilizing new technologies from an early age and should know how to keep themselves and others safe whilst accessing the Internet. However, most of them do not have the required knowledge and expertise to protect themselves. This is because, under most circumstances, the parents do not understand their children’s online behaviours and activities and are, therefore, unable to teach their children how to utilize it safe and responsibly. A school can be seen as the perfect place to teach children safe online behaviours. However, there is currently a definite lack of e-Safety in South African schools, because no e-Safety policies are in place and there is little or nothing in curricula with regards to e-Safety. This can lead to additional concerns. The primary objective of this research study is, therefore, to develop, motivate and verify a framework that might contribute towards the development of an e-Safety culture. This e-Safety culture should allow individuals to adapt their behavior towards the secure utilization of ICT. However, for the purpose of this research study, the focus will primarily be on learners from primary and secondary schools.
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  • Date Issued: 2012

The biota of the Swartkops Solar Saltworks and their potential for producing biofuels

  • Authors: De Lauwere, Monique Simone
  • Date: 2012
  • Subjects: Organisms , Biomass energy
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:10625 , http://hdl.handle.net/10948/d1011657 , Organisms , Biomass energy
  • Description: The Swartkops and Missionvale salinas in Port Elizabeth on the east coast of South Africa are surrounding by large informal settlements. The runoff from these settlements contributes largely to the eutrophication of the solar saltworks which in turn has an effect on the biotic functioning of the systems, ultimately affecting the quantity and quality of the salt produced. Inorganic nutrients and organic composition, as well as important biological groups were examined within the brine with the aim of comparing the current condition of the same salinas to their condition twelve years ago. Comparisons between inorganic nutrient concentrations and biological groups showed significantly higher inorganic nutrients, with chlorophyll a concentrations in the Swartkops salina in 2011 being significantly higher than in 2012 and the 1999 and 2011 chlorophyll a concentrations being significantly higher than 2012 in the Missionvale salina. Microalgae found in the salinas were cultured in four different growth media. Cells were stained with Nile Red fluorescent dye in order to estimate the extent of lipids production. Five of the most promising lipid producing species were isolated into a monoculture and grown at different salinities to establish the growth and lipid production in response to salinity. Halamphora coffeaeformis and Navicula sp. were found to be the best candidate species. They grew best at salinities between 50 and 70 psu and produced lipid vesicles consuming approximately 10 percent of the cell.
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  • Date Issued: 2012

Cultural interpretations of traumatic events and post traumatic stress disorder (PTSD) symptoms of IsiXhosa-speaking adults

  • Authors: De Villiers, Derika
  • Date: 2012
  • Subjects: Post-traumatic stress disorder , Emotions and cognition , Psychic trauma
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:9878 , http://hdl.handle.net/10948/d1008379 , Post-traumatic stress disorder , Emotions and cognition , Psychic trauma
  • Description: South Africa as a country is known for its high crime rate which produces an ongoing traumatising environment for its multicultural nation. Posttraumatic stress disorder in the general South African population is thought to be more prevalent than most international norms which make this topic both relevant and important. Cultural diversity is seen to play a role in the experience of PTSD which means that it has become important to gain an understanding of the potential effect of the individual’s cultural background on the processing of a traumatic experience and the symptoms related to the experience. The proposed research focused on appraisals of the traumatic event and symptoms (in schematic and cultural terms). An interpretive (with current cognitive conceptions of the disorder as guiding theory) phenomenological approach was used. The sample consisted of eight isiXhosa-speaking adults that qualified for a diagnosis of PTSD with no prior psychiatric diagnosis. Data was gathered using a semi-structured interview and analysed using the Interpretive Phenomenological Analysis. Results indicated that participants understood their PTSD symptoms in a functional manner but struggled to make sense of their traumatic event. Not understanding their traumatic event was the variable that maintained their PTSD diagnosis. Most of the interpretations made by these participants were fairly universal and there were very few links to content that can directly be attributed to a traditional African worldview. Practitioners may not need to completely reinvent the wheel as far as treatment strategies for PTSD for isiXhosa-speaking individuals in an urban setting go.
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  • Date Issued: 2012

Factors affecting survivorship of loggerhead (Caretta caretta) and leatherback (Dermochelys coriacea) sea turtles of South Africa

  • Authors: De Wet, Anje
  • Date: 2012
  • Subjects: Loggerhead turtle -- South Africa , Leatherback turtle -- South Africa , Sea turtles -- South Africa
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:10686 , http://hdl.handle.net/10948/d1007900 , Loggerhead turtle -- South Africa , Leatherback turtle -- South Africa , Sea turtles -- South Africa
  • Description: Loggerhead (Caretta caretta) and leatherback (Dermochelys coriacea) sea turtles as well as their eggs and hatchlings have been protected on their nesting beach in South Africa (SA) since 1963. Both nesting populations were expected to show similar trends in recovery following the application of identical protection and conservation measures. The loggerhead nesting population has responded favourably to these protection efforts. In contrast, the leatherback nesting population showed an initial increase but is currently stable. The reason for this difference in response is thought to be due to differential offshore mortality of these two species. This prompted an investigation into the different sources of sea turtle mortality in the South Western Indian Ocean (SWIO). Specific aims were to identify and quantify sources of loggerhead and leatherback mortality on nesting beaches as well as in the oceans. Reasonable survivorship at all age classes is important to ensure recruitment of new nesting individuals into sea turtle populations. Mortality of nests, eggs per nest and hatchlings were quantified over two seasons for the loggerheads and leatherbacks nesting in SA. The beach was patrolled on foot to encounter and record females emerging from the ocean and later, hatchlings from their nests. The nests were then monitored during the incubation period and excavated once hatched. The fates of 925 nests were determined during these two nesting seasons (2009/2010 and 2010/2011). The main source of loggerhead and leatherback nest destruction was predation (8.6 percent and 15.7 percent respectively) followed by nest erosion (2.2 percent and 6.3 percent respectively). Overall nest success was high but higher for loggerheads (89 percent) than for leatherbacks (78 percent). The main cause of egg mortality for both species was early developmental arrest, followed by predation by ants and ghost crabs. Hatchlings en route to the sea were almost exclusively predated by ghost crabs (4.2 percent of emerged loggerhead hatchlings and 3.2 percent of emerged leatherback hatchlings). It appears that both species benefit from the coastal conservation efforts. When sea turtles leave the nesting beach, either as hatchlings or adults, conservation and monitoring becomes more difficult and sea turtles are exposed to a multitude of threats, including anthropogenic threats. Age classes tend to be spatially separated due to different habitat and dietary requirements. The type of threat sea turtles are exposed to thus depends on the current age class. Offshore sources of mortality in the SWIO were identified and where possible loggerhead and leatherback mortality was quantified and mapped spatially. Loggerheads were mostly exposed to and had the highest mortality in the artisanal fisheries in the SWIO (> 1000 per annum), inshore trawling (ca. 41 per annum), shark nets (protective gill nets) (21.6 ± 6.7 per annum) and the pelagic longline fishery (5.0 ± 4.4 per annum). In contrast, leatherbacks with a pelagic lifestyle, were mostly exposed to pelagic longline fisheries (7.8 ± 7.8 per annum). A spatial analysis of fishing activities indicated that leatherback home ranges overlapped 41percent with pelagic longline fishing activity in the SA EEZ, whereas the overlap between pelagic longliners and loggerhead home ranges was 29 percent. The quantified sources of mortality provide some explanation for the trend in the loggerhead nesting population but not the trend in the leatherback nesting population. Hatchling survivorship to adulthood was estimated to determine the viability of the two nesting populations as well as to determine whether offshore mortality was responsible for the difference in recovery of the two populations. Loggerhead hatchling survivorship to adulthood was estimated at between 2 and 10 per 1000 hatchlings, the minimum requirement for an increasing population. The adopted sophisticated model shows that leatherbacks have a survival rate of 5 to 10 per 1 000 hatchlings. However, this suggests that the population is increasing, but the leatherback population is stable. Perhaps the age to maturity of SA leatherbacks is greater than 12 years, or fisheries-related mortality affects younger age classes than initially thought. It is therefore recommended that the turtle monitoring area is extended to include other potential nesting grounds. In addition, observer or monitoring programs for commercial as well as artisanal fisheries needs to be extended throughout the SWIO to quantify sea turtle mortality. Ultimately a comprehensive multi-regional approach is required for the conservation of these highly migratory species.
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  • Date Issued: 2012

Factors contributing to the dropout rate of learners at selected high schools in Kings William's Town

  • Authors: Dekeza-Tsomo, Ntombikazi Gloria
  • Date: 2012
  • Subjects: High school dropouts -- South Africa -- Kings William's Town , Problem children
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:8174 , http://hdl.handle.net/10948/1593 , High school dropouts -- South Africa -- Kings William's Town , Problem children
  • Description: Once learners reach high school, they seem to lose focus and become less interested in fulfilling their educational goals. This leads to learner dropout in schools. Yet, the government expects all children to attend school daily and receive the best education so that they can have a bright future. Education prepares the child for life, if the child drops out, he or she will struggle to succeed in life. There are real social reasons that make it difficult for some learners to succeed and lead to them dropping out of school. For example, many learners in South Africa are extremely poor and they dropout because their parents cannot provide for their families. Dropout learners from poor backgrounds also tend to be involved in crime. Young people are under a lot of pressure and consequently, they end up using drugs, smoking cigarettes and drinking alcohol instead of going to school. Teenage stress also contributes to learner dropout. The transition from childhood to adulthood brings challenges, thus making teenagers vulnerable to physical and emotional stress. Many learners do not get the support they need when they are experiencing stress. The high stress levels experienced by learners tend to result in high levels of absenteeism. Pregnancy seems to be another contributing factor to the dropout of learners from school. Thus, learner dropout is a significant problem within the South African context. Not only is learner dropout a problem, but it is linked to many other issues that negatively affect society. This study has examined factors influencing learners to dropout. It employed a qualitative research methodology, using interviews and questionnaires to elicit and investigate the causal factors of learner dropouts. The researcher made use of non-probability sampling because it can be regarded as the only sampling method that makes possible representative sampling design. Purposive sampling was used for the research, because it was convenient for the researcher in terms of time. By using purposive sampling the researcher was able to include participants according to the relevant criteria based on the emerging research questions. The principal, one educator and 18 learners in each of the two high schools were chosen as participants of the study. These participants were coming from two high schools, which are located in King William‟s Town District. Learners who participated in the iv study were chosen from grade 10, 11 and 12. There were six learners chosen per grade. The sampling method used to select learners from grade 10 to 12 and educators was purposive sampling. This type of sampling was used because the researcher wanted rich information from participants and individuals who can express themselves very well about the reasons of learners dropping out at school and also who met the sampling criterion of having had the experience of dropping out of school. The purpose of this study was to investigate factors contributing to the dropout rate of learners at selected high schools in King William‟s Town District. A purposive sampling technique was used to select the participants. The study population was confined to two public high schools in the King William‟s Town District. Using qualitative methodologies, involving a sample of 36 learners, two educators and two principals, the study found multiple motives, associated with individual characteristics of dropouts and social problems emanating from their family background and influence of the community, prompting the learners to dropout. It emerged from the empirical findings of this study that learner dropout is inter alia caused by social factors such as teenage pregnancy, drug abuse, HIV or AIDS infection, gangsterism and learning barriers. These factors are complex issues, which should be handled by skilled people. As learners spend a great deal of their time in the school environment, the educator has become an important role-player to assist learners to alleviate social problems. It is essential that learners with social problems should at an early stage get professional help. The educators who are, due to circumstances, are obliged to help these learners, are not necessarily equipped to give the required assistance. Suggestions and recommendations are espoused to alleviate the situation.
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  • Date Issued: 2012

Development of a hydraulic sub-model as part of a desktop environmental flow assessment method

  • Authors: Desai, Ahmed Yacoob
  • Date: 2012
  • Subjects: Hydrologic models -- Research -- South Africa Hydraulic engineering -- South Africa Rivers -- South Africa
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:6041 , http://hdl.handle.net/10962/d1006200
  • Description: Countries around the world have been developing ecological policies to protect their water resources and minimise the impacts of development on their river systems. The concept of ‘minimum flows’ was initially established as a solution but it did not provide sufficient protection as all elements of a flow regime were found to be important for the protection of the river ecosystem. “Environmental flows” were developed to determine these flow regimes to maintain a river in some defined ecological condition. Rapid, initial estimates of the quantity component of environmental flows may be determined using the Desktop Reserve Model in South Africa. However, the Desktop Reserve Model is dependent upon the characteristics of the reference natural hydrology used. The advancements in hydraulic and ecological relationships from the past decade have prompted the development of a Revised Desktop Reserve Model (RDRM) that would incorporate these relationships. The research in this thesis presents the development of the hydraulic sub-model for the RDRM. The hydraulic sub-model was designed to produce a realistic representation of the hydraulic conditions using hydraulic parameters/characteristics from readily available information for any part of South Africa. Hydraulic data from past EWR studies were used to estimate the hydraulic parameters. These estimated hydraulic parameters were used to develop hydraulic estimation relationships and these relationships were developed based on a combination of regression and rule-based procedures. The estimation relationships were incorporated into the hydraulic sub-model of the integrated RDRM and assessments of the hydraulic outputs and EWR results were undertaken to assess the ‘applicability’ of the hydraulic sub-model. The hydraulic sub-model was assessed to be at a stage where it can satisfactorily be incorporated in the RDRM and that it is adequately robust in many situations. Recommendations for future work include the refinement of estimation of the channel forming discharge or the use of spatial imagery to check the maximum channel width estimation. It is also proposed that a future version of the hydraulic sub-model could include flow regime change impacts on channel geomorphology and sedimentology so that flow management scenarios can be more effectively assessed.
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  • Date Issued: 2012

Knowledge retention strategies in selected Southern Africa public broadcasting corporations

  • Authors: Dewah, Peterson
  • Date: 2012
  • Subjects: Knowledge management , Intellectual capital -- Management , Employee retention , Broadcasting -- South Africa , Broadcasting -- Zimbabwe , Broadcasting -- Botswana
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:11572 , http://hdl.handle.net/10353/438 , Knowledge management , Intellectual capital -- Management , Employee retention , Broadcasting -- South Africa , Broadcasting -- Zimbabwe , Broadcasting -- Botswana
  • Description: Knowledge is now regarded as the most important resource surpassing other resources like land and capital. It is a foregone conclusion that knowledge flows out of organizations through various ways such as resignations, retirement and death yet, it does not seem as if organizations are employing strategies to retain such a vital component of production and service delivery. This study investigated the knowledge retention strategies in three Southern Africa Development Community (SADC) public broadcasting organizations of the South African Broadcasting Corporation in South African (SABC), the Department of Broadcasting Services (DBS) in Botswana and the Zimbabwe Broadcasting Corporation (ZBC) in Zimbabwe. The aim of this study was to establish how knowledge is captured and retained at such organizations. The objectives of the study were; to find out the types of strategies the three broadcasting organizations employ to capture and retain knowledge; establish how the three broadcasting organizational cultures enable knowledge acquisition, transfer, sharing and retention; establish the role of ICTs as tools and enablers of knowledge retention, creation, transfer and sharing in the three broadcasting organizations; and to propose recommendations on the best strategies for retention of knowledge in the three public broadcasting organizations as well as suggest areas for further and future research. v The study used the survey method and employed the triangulation design for data gathering. Data were collected from three SADC public broadcasting organizations. The population sample comprised 240 professional staff including 38 managers from different sections of the broadcasting organizations. The researcher collected data by administering a questionnaire to staff, interviews with managers and observations. Documentary analysis was also conducted in order to supplement data and fill in gaps. The researcher was mainly interested in gathering data that would give a comprehensive picture about knowledge retention methods in broadcasting organizations. There were four main findings. First, knowledge management as a relatively new concept and practice has not yet been properly embraced in the public broadcasting organization system in order to capture and retain knowledge that is acquired and generated in the organizations. There are no measures put in place in the organizations to retain the knowledge to ensure that once those who hold vital tacit knowledge are gone, the knowledge may still be available and accessible. Second, the study established that the respective organizational cultures impede on organizational knowledge retention. The study established that there was no culture of knowledge sharing. It also emerged that employees were not free to share their knowledge because of government regulations, prevailing political contexts, mistrust and general lack of incentive to share knowledge. Third, the study established that the organizations have no strategies or systems in place to capture the experts‟ knowledge or the knowledge of experienced staff and vi those approaching retiring age. The Human Resources Departments hold exit interviews that cover issues purely to do with why the person is leaving the organization instead of recording the work experiences and expertise of the departing employees. Fourth, the study revealed that the public broadcasting organizations still lag behind in collaborative and communicative technologies that facilitate knowledge transfer and sharing of tacit knowledge but retention of knowledge generally. The study also found that, some of the organizations studied did not have internet connectivity and websites were not yet functional, which hampered acquisition and sharing of knowledge for retention purposes. The importance of this study is that it has made a contribution and provided literature on knowledge retention strategies for public broadcasting corporations as part of knowledge management practice. On the basis of these findings the study recommended the following: appointment of knowledge management officers, establishment of Communities of Practice, encouraging knowledge sharing between employees, introduction of joint programmes with other broadcasting organizations by managers and their supervision of mentoring programmes; organizations to facilitate acquisition of information and communication technologies that enable knowledge management
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  • Date Issued: 2012

Mesozooplankton dynamics in a biogeographical transition zone estuary

  • Authors: Deyzel, (Shaun) Herklaas Phillipus
  • Date: 2012
  • Subjects: Marine zooplankton -- South Africa , Benthos -- South Africa , Estuarine ecology -- South Africa , Mangrove forests
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:10687 , http://hdl.handle.net/10948/d1007901 , Marine zooplankton -- South Africa , Benthos -- South Africa , Estuarine ecology -- South Africa , Mangrove forests
  • Description: This thesis presents the first intensive community-level investigation of the mesozooplankton from a biogeographical transition zone estuary. The Mgazana Estuary is located along a rural, semi-undeveloped part of South Africa’s east coast, believed to represent a transition zone between the subtropical and warm-temperate biogeographical zones. The research represented in this thesis involves data collected over a five year period between 2002 and 2006, with additional data collection made in 2008. The study focussed on five areas of investigation, the first of which investigated the physico-chemical dynamics of the Mgazana Estuary. The Mgazana Estuary exhibited marked vertical, horizontal and regional structures in the hydrological environment. Prominent vertical and horizontal stratification characterised summer months. A substantial turbidity front was observed in the lower estuary during summer and winter. The upper estuary was marked by considerable variation in multiple variables but especially salinity. These structures appeared to have shifted in position over the horizontal plane, which was attributed to variation in freshwater flow. The second study focused on the spatial dynamics of mesozooplankton in the Mgazana Estuary. The zooplankton was rich and in terms of composition typical of mangrove systems. The Copepoda were dominant, numerically and in terms of taxonomic representation. Calanoids Acartiella natalensis and Pseudodiaptomus hessei characterised middle and upper reaches in summer and mostly upper reaches in winter. On community level, a highly structured assemblage arrangement was observed during summer and winter months. These trends were further scrutinised under the theoretical framework of ecological boundaries. In so doing, an agreeable spatial association emerged between specific assemblages and their environments. These trends were concluded to reflect ecoclinal as well as ecotonal properties, the latter describing interactions over narrow spatial bands of marked changes in turbidity. The third study investigated flooding events as short-lived extreme meteorological events and the influence on zooplankton. Within this regard, second-stage multivariate statistics was used to assess year-to-year variability in assemblage structures on whole-system and regional scales. The impact of two major flooding events that flushed the estuary some days prior to sampling could clearly be elucidated. Flooding emerged as a significant source of inter-annual variability in the zooplankton of the Mgazana Estuary. Second-stage multivariate analysis proved to be an effective analytical strategy for investigating inter-annual variability in species assemblage structures. Results from the preceding study prompted a detailed investigation into the spatio-temporal dynamics of Acartiella natalensis, the most important zooplankton species of the system aimed at elucidating flood responses. Acartiella natalensis showed indication of temporal arrest in association with flooding events in a similar fashion as is observed in seasonal variation trends in estuaries towards its geographical distribution limit south of the study area. It was concluded that A. natalensis was severely affected by floods and the possibility exist for entrainment of entire populations from the estuary during flooding events. The final study tested the hypothesis of post-flood propagation from a resting egg bank in the sediments of the Mgazana Estuary. Preliminary data revealed that numerous eggs were present in the sediments. Nauplii hatched from eggs under laboratory conditions were identified as belonging to the family Acartiidae. The preliminary mode of diapause is presented as a schematic model, emphasising the role of freshwater flow and specific environmental variables. This was the first discovery of resting eggs from a subtropical estuary from South Africa. It is hoped that the findings of this study would give rise to new research initiatives investigating the importance of resting stages in estuarine and coastal Copepoda species and the role such reproductive strategies may play in estuarine functioning.
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  • Date Issued: 2012

Evaluation for harnessing low-enthalpy geothermal energy in South Africa based on a model pilot plant in the Limpopo Mobile Belt

  • Authors: Dhansay, Taufeeq
  • Date: 2012
  • Subjects: Geothermal resources -- South Africa -- Limpopo , Renewable energy sources -- South Africa -- Limpopo , Climatic changes -- South Africa -- Limpopo
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:10667 , http://hdl.handle.net/10948/d1019789
  • Description: South Africa generates more than 90 percent of its total energy capacity through non-renewable sources. With coal forming the predominant energy source, South Africa became the leading carbon emissive nation in Africa, emitting 450 million tonnes of CO2 in 2011. In an international effort to restrict global average temperature rise to 2° C above the average prior the industrial revolution, the Kyoto Protocol has been extended for another 8-year commitment period. This is complementary to an expected resolution of a new legally binding climate change policy in 2015. This policy will aim to introduce financial penalties for nations failing to meet ascribed GHG emission targets by 2020. In an attempt to meet these climate change resolutions South Africa will research and develop cleaner, alternative forms of energy, including hydro, wind, and biomass forms of renewable energy, in addition to designating stringent building regulations for the Incorporation of solar energy. These measures form part of an Integrated evelopment Plan that aims to generate a target of 10,000 GWh of renewable energy in 2013. South Africa is also investigating the possibilities of extracting its shale gas reserves and implementing it as a major energy source. This energy mix has given little attention to geothermal energy. The reasons for this omission appears to be the lack of active volcanism and previous research that suggests South Africa, largely underlain by the Kaapvaal Craton, has a relatively low heat Flow profile, deemed insufficient for harnessing geothermal energy.
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  • Date Issued: 2012

Enumeration of insect viruses using microscopic and molecular analyses: South African isolate of cryotophlebia leucotreta granulovirus as a case study

  • Authors: Dhladhla, Busisiwe I R
  • Date: 2012
  • Subjects: Baculoviruses , Insects -- Viruses , Molecular genetics , Microbial genomics
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:10318 , http://hdl.handle.net/10948/d1008395 , Baculoviruses , Insects -- Viruses , Molecular genetics , Microbial genomics
  • Description: Baculoviruses have been used as biocontrol agents to control insect pests in agriculture since the 1970s. Out of the fifteen virus families known to infect insects, baculoviruses offer the greatest potential as insect biopesticides, due to their high host specificity which makes them extremely safe to humans, other vertebrates, plants and non-target microorganisms. They comprise of two genera: nucleopolyhedroviruses (NPVs) and granuloviruses (GVs). The South African isolate of Cryptophlebia leucotreta granulovirus (CrleGV-SA) which is infectious for the false codling moth (FCM), Thaumatotibia leucotreta, (Meyrick) (Lepidoptera: Tortricidae), has been successfully developed into two commercial biopesticides; Cryptogran® and Cryptex®, for the control of FCM in citrus crops. The current method of enumeration used for CrleGV-SA virus particles in routine experiments during the production of the GV as biopesticides, is dark field microscopy. However, due to the small size of GVs (300-500 nm in length), the technique is not easy to perform on these viruses, and no systemic comparison has been made of potential alternative methods. Therefore, the main objective of this study was to develop a quantitative enumeration method for CrleGV-SA occlusion bodies (OBs) which is accurate, reliable, and feasible, and compare the developed methods of enumeration to the current method. Purified and semi-purified CrleGV-SA viral stocks were prepared for enumeration studies using spectrophotometry, dark field microscopy, scanning electron microscopy (SEM) and real time qPCR. Spectrophotometry was found to be an unreliable method for enumeration of GVs in the production, standardisation, and quality control of biopesticides. Dark field microscopy and SEM were found to be accurate, and statistically comparable (p = 0.064) enumeration techniques. qPCR is currently being optimised for the enumeration of GVs. This technique was demonstrated to generate accurate standard curves for absolute quantification of virus particles for pure and semi-pure virus preparations. qPCR offers the greatest potential as an accurate enumeration method because it is not affected by contamination with non-biological contaminating debris, nor by other biological material due to the specificity of PCR primers. Further work is required to fully develop qPCR as an enumeration method for GVs. However, dark field microscopy has been successfully validated as an enumeration method. SEM, which has a high resolution compared to light microscopy, has an added advantage over dark field microscopy, which is to distinguish virus particles in semi-pure viral stock preparations during counting. Therefore, SEM currently provides the most unambiguous and feasible enumeration method for GVs in both purified and semi-purified virus samples.
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  • Date Issued: 2012

Long-term catch and effort trends in Eastern Cape Angling Week competitions

  • Authors: Dicken, Matthew L , Smale, Malcolm J , Booth, Anthony J
  • Date: 2012
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/124931 , vital:35711 , https://doi.org/10.2989/1814232X.2012.709961
  • Description: Recreational shore-based angling is one of the most popular sport and outdoor activity pastimes in South Africa with an estimated 412 000 fishers (McGrath et al. 1997). It is a form of linefishing where fish are caught using a hook and line and comprises a social as well as a more formal organized competitive sector (van der Elst 1989). Similar to other components of the linefishery, which include the subsistence as well as boat-based commercial sectors, excessive shore-fishing effort along the Eastern Cape has resulted not only in declining catches (Bennett 1991, Griffiths 1997, Brouwer and Buxton 2002, Pradervand and Govender 2003) but also changes in the species composition of catches (Bennett et al. 1994, Brouwer et al. 1997, Attwood and Farquhar 1999). Stock assessments indicate that many important linefish species are severely overexploited (Griffiths 1997, Hutchings 2000, Mann 2000) and that continued fishing pressure threatens endemic linefish populations. In 1996, shore-anglers alone were responsible for an annual catch of approximately 4.5 million fish, weighing around 3 000 tonnes (Brouwer et al. 1997).
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  • Date Issued: 2012

Sustainability, viability and stability : the case of income generating projects in the Nelson Mandela Bay

  • Authors: Dikana, Zukisile Christopher
  • Date: 2012
  • Subjects: Sustainable development -- South Africa -- Port Elizabeth , Public investments -- South Africa -- Port Elizabeth , Economic development projects -- South Africa -- Port Elizabeth , Community development -- South Africa -- Port Elizabeth
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:9157 , http://hdl.handle.net/10948/d1019860
  • Description: This study explores issues of sustainability, viability and stability in the projects funded by the Department of Social Development, situated in the Nelson Mandela Bay. The researcher makes use of a combination of qualitative and quantitative research designs to gather data. The sample consisted of about three members from each of the four projects selected, as well as two officials of the Department of Social Development in the Nelson Mandela Bay. The respondents participated in structured and semi-structured interviews exploring their demographic information, information about the project and how it is managed, views and opinions about differences between a business venture and a project, their understanding of what constitutes a sustainable, viable and stable income-generating project as well as their opinions about what would contribute to ensuring sustainability, viability and stability in these projects. The results of the study reveal that it is important to structure and run the income generating projects using business principles which include vigorous marketing and proper costing. There is also a need to train the participants in business management so that they can run the ventures successfully. It has also become apparent that a clear leader or manager is lacking and thus decision making process is too long, meaning a meeting must take place involving all project members before a decision that affects the operations can be made. Almost all key factors contributing to a sustainable and viable income generating project, as defined by Mango (2004) and Madi (2007) were also found to be lacking in these projects.
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  • Date Issued: 2012

Enhancing the critical reading skills of student teachers in Namibia : An action research project

  • Authors: Dikuwa, Alexander
  • Date: 2012
  • Subjects: Reading (Higher education) Critical thinking , Teachers -- Training of -- Namibia
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1912 , http://hdl.handle.net/10962/d1007162
  • Description: This thesis reports on a responsive action research case study undertaken to teach student teachers to read critically. I undertook this research to gain a basic knowledge about critical reading as well as to form a knowledge base that would enable me to teach it effectively. First, I gave students a diagnostic assessment activity, analyzed the result and established the students’ ability to read a text critically. After I had established the students’ strengths, weaknesses, and the requirements to move students from their existing critical reading competency to an improved one, I reviewed the literature to provide me with a theory of teaching critical reading. The lessons were then planned and taught. The lessons; focus group interviews; researcher’s diary; students’ reflections and non-participant observer comments formed the data of the study. The data were analyzed using the framework of “what went well”, “what did not go well” and “what needs to be improved if the lessons were to be repeated”. The main purpose was to address the goals of the research, which were to find effective ways of teaching critical reading, appropriate critical reading materials, and to identify any pedagogic shortcomings. The 30 students who took part in this research were third-year students studying English Second language and Mother tongue pedagogies to become specialists in the teaching of both at Junior Secondary level (grades 8 – 10). The study was guided by constructivist theory, which underpins learner-centred education, which continues to inform and shape the development of curricula in Namibia.
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  • Date Issued: 2012

The recognition of victims rights of sexual offences

  • Authors: Dipa, Asanda
  • Date: 2012
  • Subjects: Sex crimes -- South Africa , Criminal justice, Administration of , Sex and law -- South Africa , Victims of crimes -- South Africa
  • Language: English
  • Type: Thesis , Masters , LLM
  • Identifier: vital:10181 , http://hdl.handle.net/10948/d1014361
  • Description: “Indeed in rape cases it is the victim who is most often placed on trial rather than the perpetrator, accused of having ulterior motives and subjected to degrading questions with often pornographic overtones. Prosecutors might fail to adequately address the victims needs and all too often, information is either intentionally or unintentionally withheld from victims.” The victims of sexual offences have to face not only the consequences of the sexual crime that was perpetrated upon them, but they also have to deal with the effects of the criminal justice system. Victims who take part in the criminal justice system should not be exposed to unnecessary distress and trauma. The victims of sexual offences must not be re-victimised by the criminal justice system. Re-victimisation has been coined to describe the experience where victims are subjected to further victimisation by the very state organs to whom they turn for assistance. This has the effect that the victim is victimised twice, first by the offender and then by the criminal justice system. It is therefore the duty of the law to protect this group of witnesses from such a traumatic and damaging experience. The question that needs to be answered in this research is whether the Sexual Offences and Related Matters Amendment has made any difference in respect of protection of victims sexual crimes. It was concluded that the Sexual Offences Act is indeed a step in the right direction to protect the rights of victims of sexual offences but that it could have afforded more protection.
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  • Date Issued: 2012

The exploration of sustainable and diversified livelihood options for residents of Enon-Bersheba

  • Authors: Dlamini, Tembile Daniel
  • Date: 2012
  • Subjects: Sustainable development -- South Africa -- Eastern Cape , Sustainable living -- South Africa -- Eastern Cape , Sustainable living
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:9115 , http://hdl.handle.net/10948/d1015643
  • Description: Enon-Bersheba (E&B) area has approximately 10 200 hectors of pristine communal land that is rare to find in the Cacadu region. This prime communal land is situated in the bank of the Sundays River Valley in the Eastern Cape Province. Enon-Bersheba falls under the jurisdiction of the Sundays River Local Municipality. The Municipal jurisdiction provides easy access to this pristine commonage that presents opportunities for economic development as well as residential opportunities. This study presents the diversity of sustainable livelihood alternatives from the community‟s perspective. This study finds that giving the beneficiaries of land restitution authority over decision-making on land usage is an important contributor to success. Land is a significant asset, and it becomes more valuable and development-worthy if legal institutions are in place to manage the planning and development processes, for its full utilisation. In addition to this, the study provides a community-driven development framework with which potential development partners can interact to enhance revenue generating activities and strengthen the institutional environment through the formation of community-private-public-partnerships. The participatory research process that was undertaken made essential findings. The study validates the use of livelihoods-based approach to poverty alleviation. A bottom-up participatory process was effective in determining how best Enon-Bersheba communal land can be put into effective and efficient use. Likewise, an integrated approach to development planning was proven to be important. This study proved an extra-ordinary belief that the stability and changed value systems within a community often derive from complex social problems that are inherently dynamic. The involvement of the Independent Electoral Commission in the referendum process for Enon-Bersheba‟s legal entity that will manage the land suggests the credibility of the process. The existing information around potential development options of Enon-Bersheba was consolidated and verified by the community. The awareness of community abilities and resources served to enhance community mobilization for social action. The study provides a framework for development policy imperatives and a new vision for Enon-Bersheba.
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  • Date Issued: 2012

The economics of converting a sheep farm into a springbuck (Antidorcas marsupialis) ranch in Graaff-Reinet: a simulation analysis

  • Authors: Dlamini, Thula Sizwe
  • Date: 2012
  • Subjects: Livestock projects -- South Africa -- Eastern Cape Livestock productivity -- South Africa -- Eastern Cape Livestock -- Economic aspects -- South Africa -- Eastern Cape Sheep -- Breeding -- South Africa -- Eastern Cape Springbok -- Breeding -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:1003 , http://hdl.handle.net/10962/d1002738
  • Description: In Graaff-Reinet, domestic livestock farming and springbuck ranching are similar in that they both rely on the rangeland for their sustainability. However, as a consequence of repeated monotonous domestic livestock farming, resulting in compromised biological productivity and diversity, the rangelands have disintegrated. This, unfortunately, has placed the future sustainability of these rangelands and the livelihoods of the local people in an indeterminate state. In recent years, there has been an increasing interest in springbuck ranching for meat production as an alternative to domestic livestock farming in the area following (a) fears of worsening environmental challenges; (b) declining profitability in commercial domestic livestock farming and; (c) growing calls for the sustainable use of these rangelands for the benefit of future generations. The springbuck has emerged as a credible alternative to utilising the rangelands - as opposed to sheep - because of its promise to addressing the above challenges. This is in an attempt to tap into the multitude of benefits that the springbuck possesses (by virtue of being part of the natural capital of the area) that have a potential towards restoring ecological integrity by extenuating some of the detrimental effects of sheep farming on the rangelands and presenting opportunities for diversifying incomes. Yet, despite the general increase in interest, a resistance towards the uptake of springbuck ranching for meat production exists. The main contention is that springbuck meat production cannot out-perform the economic returns of wool sheep farming. This study attempts to address these concerns by investigating the profitability and economic sustainability of converting a sheep farm into a springbuck ranch in Graaff-Reinet. The study uses stochastic simulation to estimate the probability distribution of some key output variables, namely: net cash income, ending cash balance, real net worth and the net present value (NPV) in evaluating the profitability of converting a 5 000ha sheep-dominated farm into a springbuck-dominated ranch under three alternative scenarios. The use of stochastic simulation allows for the incorporation of downside risk associated with the production and marketing of wool, mutton and springbuck meat. The study uses stochastic prices and yields to calculate net returns variability. Incorporating scenario analysis helped to evaluate how alternative wool sheep-dominated and springbuck-dominated combinations would perform based on the probable outcomes of different assumptions in the various scenarios. By applying stochastic efficiency with respect to a function (SERF) criterion to the simulated NPVs, this study compares the profitability of alternative scenarios based on various risk aversion coefficients. The study finds that converting a 5 000ha wool sheep dominated farm into a springbuck dominated ranch could potentially be a more profitable investment than wool sheep farming over a 15 year planning horizon, in Graaff-Reinet. The SERF results indicate that for all scenarios tested, the best strategy of converting a wool sheep dominated farm into a springbuck ranch would be one which comprise a combination of 70% springbuck, 20% mutton and 10% wool production as the likely profitable enterprise mix. Using economic sustainability analysis, the study reveals that because of low costs in springbuck ranching, springbuck meat production enterprises are most likely to be more financially sustainable than wool sheep-dominated enterprises. This suggests that rangeland owners may be better off converting their wool sheep-dominated farms into springbuck-dominated ranches. Thus, as the call for more environmentally benign rangeland utilising economic-ecological systems intensifies, rangeland owners in the Eastern Cape Karoo have a practicable option. At the very least, there exists an option to broaden their incomes whilst promoting ecological restoration with springbuck meat production.
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  • Date Issued: 2012

Teachers’ perceptions of the mentoring of novice teachers in the King William’s Town District

  • Authors: Dlani, Siyongwana Archibald
  • Date: 2012
  • Subjects: Teachers -- Training of -- South Africa -- Eastern Cape , Teachers -- In-service training -- South Africa -- Eastern Cape , Mentoring in education -- South Africa -- Eastern Cape , School management and organization -- South Africa -- Eastern Cape , Schools -- South Africa -- Eastern Cape , King William's Town (South Africa)
  • Language: English
  • Type: Thesis , Masters , M Ed
  • Identifier: vital:16184 , http://hdl.handle.net/10353/d1006244 , Teachers -- Training of -- South Africa -- Eastern Cape , Teachers -- In-service training -- South Africa -- Eastern Cape , Mentoring in education -- South Africa -- Eastern Cape , School management and organization -- South Africa -- Eastern Cape , Schools -- South Africa -- Eastern Cape , King William's Town (South Africa)
  • Description: The aim of the study was to investigate the teachers‟ perceptions of thementoring of novice teachers in the King William‟s Town District. Inorder to understand how the teachers viewed novice teacher mentoringthe study adopted a qualitative approach. Interviews anddocumentsanalysis were used as data collection instruments. The purpose of the study was to investigate the teachers‟ perceptions on mentoring of novice teachers in schools. The respondents provided their explanationsof mentoring and also said what they think is the importance of mentoring. The teachers also had to give their mentoring experiences at school and District levels. Two schools in the King William‟s Town District were purposivelyselected to form the context of the study. The respondents were 6 educators, three from a primary school and three from a high school. Principals of the two selected schools were also included asrespondents in the study. The results of the study revealed that mentoring was taking place informally in the schools through sharing ofthe teaching challenges. Mentoring was also taking place through theteachers mentoring each other as Subject and Phase teachers supervised by Heads of Department. Most teachers understoodmentoring as giving guidance and help.
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  • Date Issued: 2012

The integration of mental health care services into primary health care system at King Sabata Dalindyebo Municipality Clinics

  • Authors: Dlatu, Ntandazo
  • Date: 2012
  • Subjects: Community mental health services South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , MPH
  • Identifier: vital:18478 , http://hdl.handle.net/11260/d1008290
  • Description: Introduction: Primary Health care refers to care which is based on the needs of population. Mental health care provided within general primary care services is the first level of care within the formal health system. There is no research in King Sabata Dalindyebo, carried out on issues around integration of mental health with primary health care. The present study is initiated to overcome this gap. Aim of the study: The aim of the study was to investigate the level of knowledge, implementation and barriers of integrating mental health care services into primary health care system at King Sabata Dalindyebo clinics, in Mthatha region. Methods: This descriptive cross-sectional study was conducted at King Sabata Dalindyebo Clinics, between January 2010 and December 2011. A 10% random sample of all health professionals from King Sabata Dalindyebo was interviewed concerning their demographic characteristics, education/ qualifications, general and further training in psychiatry, awareness about Mental Health Care Act 17 of 2002 and mental health care services characteristic related to the integration of mental health care services into primary health care system. For data analysis, the means of continuous variables across 2 groups were compared using Student-t test. The proportions (%) of the categorical variable across 2 groups were compared using Chi-square test. Results: A total of 52 health professionals (40.4% males, 59.6 females, 59.6 married, 3 doctors, 49 nurses, mean age 36.9± 8 years range 23 years-52 years), were surveyed. The participants were characterized by low level of qualification in specialization, further training in psychiatry, and by very low awareness about Mental Health Care Act 17 of 2002. Furthermore, there was no implication of expects (Regional psychiatrist, psychologist, social worker) and co-ordination of mental health care services. Working in remote and disadvantaged area, health workers with lower education qualification, absence of a coordinator for mental health care services and absence of workshop on Mental Health Care Act 17 of 2002 were determinants of lower awareness about Mental Health Care Act 17 of 2002. However, there was a good to excellent framework for potential implementation of mental health care services into primary health care system. The government support in infrastructures, drugs availability, transport and equipment was evident. Patients were helped within abroad based ethical, human rights and psycho-social framework. Conclusion: There is a lack of improving human capacity for mental health in terms of continuous training in mental health issues, policies, organisation and development. Globally, the integration of mental health care service in King Sabata Dalindyebo is non-optimal.
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  • Date Issued: 2012

An investigation into constraints impacting on small micro and medium enterprises (SMMEs) access to finance in Buffalo City Metropolitan Municipality

  • Authors: Dlova, Mzwanele Roadwell
  • Date: 2012
  • Subjects: Small business -- South Africa -- East London Small business -- Finance -- South Africa -- East London
  • Language: English
  • Type: Thesis , Masters , MBA
  • Identifier: vital:783 , http://hdl.handle.net/10962/d1003904
  • Description: Internationally, in both developed and developing countries, it has been accepted that SMMEs are the backbone and the driving force of economic growth and job creation. In South Africa, SMMEs account for approximately 60 per cent of all employment in the economy and more than 35 per cent of South Africa's Gross Domestic Product (GDP) (Ntsika, 1999:38; Gumede, 2000:67 and Berry et ai, 2002 in Kongolo, 2010:235). SMMEs are often the vehicle by which the lowest income people in our society gain access to economic opportunities. The sector represents 97.5 per cent of the total number of business firms in South Africa and that it contributes 42 per cent of total remuneration. SMMEs account for some 3.5 million jobs and have between 500 000 and 700 000 businesses (Abor and Quartey, 2010:2337). Due to the above-mentioned contribution, the South African government initiated a number of SMME support programmes aimed at promoting, growing and developing the SMME sector. As a result, a number of national government agencies such as the National Youth Development Agency (NYDA), Khula Finance Limited, the National Development Agency (NDA), the Small Enterprise Development Agency (SEDA) and many other national , provincial and local government organizations were established post 1994. However, despite the concerted efforts by government to develop the sector, SMMEs are, after 17 years of democracy, still faced with enormous challenges such as access to markets, information, appropriate technology, finance, to mention but a few. Of the above-mentioned challenges, access to finance is on top of the list of these. This study, therefore, is aimed at investigating external, institutional and internal constraints impacting on SMME access to finance in the Buffalo City Metropolitan Municipal area. The study is also aimed at ascertaining which of the abovementioned constraints have the greatest influence to SMME access to finance. In developing the framework of the study, recent empirical research conducted around the country and internationally on constraints influencing SMME access to finance (Bbenkele, 2007:18; Ganbold, 2008:45; Mahadea and Pillay, 2008:99; Chenesai, 2009:135; Zindiye, 2009:78; Fatoki and Garwe, 2010:2765; Pandula, 2011 :257) was drawn upon. In order to meet the objectives of the study, a simple random sample survey of 50 SMMEs in the Buffalo City Metropolitan Municipality (BCMM) jurisdiction was conducted. The profile of the SMMEs was very similar to that of other studies that focused on constraints to SMME access to finance. A structured questionnaire was used to collect data from SMME owner-managers and a response rate of 60 percent was achieved . The results of the study indicated that the high cost of credit and interest rates and Value Added Tax (VAT) registration were the key external factors that impacted on SMME access to finance. Generally, SMMEs are viewed by lending institutions as high risk category. Therefore, even though interest rates have come down significantly, the cost of credit and interest rates still remain a constraint. The study also found that even though the South African Revenue Services (SARS) has increased the VAT threshold to R1 million (South African Revenue Service, 2007: 29), SMMEs still struggled to register for VAT. With regards to the institutional factors, the study revealed that ineffective support services provided by private and public SMME support agencies, the lack of communication of these services (access to information) and the lack of the subsequent follow-up services were the key constraints to SMME access to finance. The results of the study indicate that those firms with good track record, high annual turnover, sophistication and diverse skills, good credit record, good cash flow, proper financial records, bankable and viable business plans, collateral and registered for VAT were more likely to have access to finance than their counterparts. The main conclusion of the study is that the internal factors turned to have the greatest influence to SMME access to finance. However, there is more to be done by private and public SMME support agencies and lending institutions to address the above-mentioned institutional constraints which have a negative influence to SMME access to finance. It is recommended that more in-depth empirical research be conducted on the support services provided by private and public SMME support agencies in terms of the services that they offer the effectiveness of the services and how these are communicated to potential customers. It is also recommended that training workshops aimed at addressing the intemal constraints identified be conducted. Also recommended is the development and implementation of sector-specific mentoring programmes for the owner-managers. Strategies to improve the awareness of support services provided by SMME support agencies need to be developed. This would ensure the effective use of these services by SMMEs. It is also recommended that SMME support agencies and lending institutions staff be trained in order to better understand and be more responsive to the owner managers' needs. Linkages with tertiary institutions in planning and conducting the training needs to be made.
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  • Date Issued: 2012
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