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Evaluating the effect of microalgae biomass on the combustion of coal

  • Authors: Ejesieme, Obialo Vitus
  • Date: 2013
  • Subjects: Co-combustion , Coal -- Combustion , Biomass -- Combustion
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:10435 , http://hdl.handle.net/10948/d1020641
  • Description: In this work the combustion characteristics of coal, charcoal, microalgae biomass and blends between these three components were evaluated by means of non-isothermal thermogravimetry. Blends between coal, charcoal and microalgae biomass were made according to the specifications of a D-optimal mixture design so as to be able to model interactions between the three components with maximum precision despite multiple constraints built into the design. These constraints specified that coal can have a minimum value of 70 mass percent in any blend, while microalgae can have a maximum value of 20 mass percent. While coal and charcoal were blended by mixing the two respective dry components, microalgae biomass was incorporated into the blends by first absorbing microalgae onto fine coal from concentrated slurry of the microalgae in water. The microalgae in these blends were therefore intimately associated with the coal. This approach differed substantially from the normal practice of preparing coal – biomass blends (which are usually dry-mixed as for coal – charcoal blends). Proximate analyses of the starting materials showed that the microalgae biomass has a significantly higher volatile matter: fixed carbon content than both coal and charcoal, which should improve the combustion of these materials by providing a more stable combustion flame. Analyses of the thermogravimetric data obtained showed that coal and charcoal have much simpler combustion profiles than microalgae biomass for which five different thermal events could be observed in the DTG combustion profile. Qualitative kinetic analyses showed that the combustion of coal and charcoal follows first-order kinetics, but for microalgae biomass combustion, the first two combustion stages appear to follow first-order kinetics. The TG and DTG profiles for coal, charcoal, microalgae and blends of these three components were used to derive values for the so-called comprehensive combustion property index (S-value), which provides a combined measure of the ease of ignition, rate of combustion, and burn-out temperature. The S-values so obtained were used as response variable for the construction of a response surface model in the experimental domain investigated. Following statistical validation of the response surface model, the model was used to predict an optimum S-value or a blend that would display optimum combustion behaviour. Two optimum blends were obtained from the optimisation process, one in which only charcoal is added to coal, and one in which only microalgae is added to coal. Adding both charcoal and microalgae produced an antagonistic effect compared to when only one of these are used. Qualitative kinetic analyses of the combustion data of blends indicate that blends of coal and charcoal combust in a manner similar to the individual components (hence following first-order kinetics), but blends of coal and microalgae follow more complex kinetics despite the fact that the combustion profile is visibly more simple compared to the combustion profile for microalgae alone.
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  • Date Issued: 2013

Students' perceptions of service quality levels of students housing at the large metropolitan university

  • Authors: Elie, Sammy Abraham
  • Date: 2013
  • Subjects: SERVQUAL (Service quality framework) , Student housing -- Resident satisfaction -- South Africa , Consumer satisfaction -- South Africa , Nelson Mandela Metropolitan University -- Student housing
  • Language: English
  • Type: Thesis , Masters , MBA
  • Identifier: vital:8869 , http://hdl.handle.net/10948/d1020297
  • Description: The increasing attention to the provision of accessible, decent, safe and academically appropriate student housing in South Africa has led to a closer investigation of the nature and levels of quality in both on-campus and off-campus student accommodation. Nationwide, student housing management recognises that quality student housing is of great importance to both the quality of the higher education system and the success of students. In recent years, many studies in the field of service quality have been conducted within higher education. However, fewer studies have focused specifically on service quality in student housing. The purpose of this study was to evaluate the perceptions of students with regard to service quality levels in on-campus and off-campus student housing at NMMU, and to identify those service quality dimensions that need attention. A literature review was conducted to explore the meaning and nature of service and quality in student housing. It was concluded that from the different facets of service that quality, customer expectations, customer perception and customer satisfaction are important constructs in evaluating fully the levels of service quality. An amended SERVQUAL instrument comprising 41 items was used for students, in order to evaluate the service quality at on-campus and accredited off-campus student housing at NMMU. The results showed that there are significant differences in the service quality dimensions of on-campus student housing and off-campus student housing. Oncampus student housing gleaned a positive assessment for the dimensions of reliability, responsiveness, empathy and assurance. However, negative perceptions prevail with regard to on-campus infrastructural/tangible issues. The off-campus student housing fell short in a number of service-quality dimensions, including reliability, empathy, responsiveness and infrastructural/tangible issues. The assurance dimension received positive assessments for both on-campus and off-campus student housing. The study proposes that the NMMU student housing management pay attention to the shortcomings and make the desired improvements. The findings of this treatise have practical implications for student-housing managers, as they could direct their resources to improving poor service dimensions, and similarly refine marketing strategies, so that students’ needs are met in an exceptional and satisfactory manner.
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  • Date Issued: 2013

Morphology, patterns and processes in the Oyster Bay headland bypass dunefield, South Africa

  • Authors: Elkington, Lauren
  • Date: 2013
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:20984 , http://hdl.handle.net/10962/5879
  • Description: Studies of the dunefield systems crossing the Cape St. Francis headland in the Eastern Cape have focused on the role that wind plays in sediment transfer in coastal dunefield systems, with limited consideration of the role of water. The aim of this study was to improve understanding of the morphology, processes and patterns within the Oyster Bay HBD system, focussing particularly on surface water and groundwater interactions and the role of surface water in sediment transfer across the dunefield system. An extensive field survey was conducted, to collect related data, complimented by spatial and temporal analysis of the study area using GIS. The key findings from this research were the apparent differences between the western and eastern regions of the dunefield with regard to specific drivers and the respective processes and responses. Wind is the major driver of change up to and across the crest of the dunefield. In the eastern region water (ground water, surface water and the Sand River System) is the primary agent of sediment flux through processes of aggregation and slumping as well as episodic events including debris flows. This study has highlighted a need for further quantitative studies that investigate the movement of sediment through dunefield systems such as this (where water is at or near the land surface). The paradigm that sediment flux is entirely due to wind is almost certainly simplistic, and deeper understanding of these systems is needed.
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  • Date Issued: 2013

Revision of Aloiampelos Klopper & Gideon F.Sm. (xanthorrhoeaceae subfam. asphodeloideae)

  • Authors: Ellis, Kristen
  • Date: 2013
  • Subjects: Xanthorrhoeaceae , Asparagales
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:10642 , http://hdl.handle.net/10948/d1020955
  • Description: The genus Aloiampelos Klopper & Gideon F.Sm., previously treated as Aloe L. Ser. Macrifoliae (Sect. Prolongatae), comprises seven species with barely succulent leaves that are popularly known as rambling, scrambling or climbing aloes, because they make use of surrounding trees and shrubs for support. The rambling aloes are centered in the Eastern Cape but some species have disjunct distributions in the Western Cape and KwaZulu-Natal. Many are widely used in gardens and landscaping. With their rambling habit and weakly succulent leaves, the genus is widely considered to be an old lineage among alooid genera. Species concepts within the genus remain contentious, with disagreement amongst taxonomists with respect to the recognition of some taxa at the rank of variety. Morphology, historical taxonomy, palynology and phylogenetics of the genus were investigated. The occasional presence of minute cilia on the sheathing leaf bases and distinct lineation of the leaf sheaths of Aloiampelos tenuior var. decidua and Aloiampelos tenuior var. rubriflora were the most important outcomes of the morphological study. The pollen grains of all species studied were very similar in grain shape and exine surface pattern, with only minor differences in grain size. Ordination analyses showed that grain length and muri length were useful at the infraspecific level, with Aloiampelos tenuior “orange” separating clearly from the other varieties. Pollen morphology was therefore not informative as a taxonomic character at species level when used in isolation, but may be useful when used in conjunction with other characteristics. Preliminary analyses of two plastid barcoding regions (matK and rbcL) and nuclear ITS have confirmed that Aloiampelos is monophyletic. These barcoding markers were not informative in assessing the species boundaries among the closely related taxa in the genus and morphological assessments were therefore used to elucidate relationships at the species rank. A key is given for the genus, integrating the findings of the study.
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  • Date Issued: 2013

The limitations and possiblilites of identity and form in selected recent memoirs and novels by white, female Zimbabwean writers : Alexandra Fuller, Lauren Liebenberg

  • Authors: Eppel, Ruth
  • Date: 2013
  • Subjects: Women, White -- Zimbabwe -- Biography Women, White -- Zimbabwe -- Fiction Zimbabwean fiction (English) -- 21st century Women, White -- Zimbabwe -- Autobiography Fuller, Alexandra, 1969- Liebenberg, Lauren St. John, Lauren,1966- Rheam, Bryony
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2185 , http://hdl.handle.net/10962/d1001985
  • Description: This study examines selected works by four white female Zimbabwean writers: Alexandra Fuller, Lauren Liebenberg, Bryony Rheam and Lauren St John, in light of the controversy over the spate of white memoirs which followed the violent confiscation of white farms in Zimbabwe from 2000 onwards. The controversy hinges on the notion that white memoir writers exploit the perceived victimhood of white Zimbabweans in the international sphere, and nostalgically recall a time of belonging – as children in Rhodesia – which fails to address the fraught colonial history which is directly related to the current political climate of the country. I argue that such critiques are too generalised, and I regard the selected texts as primarily critical of the values and lifestyles of white Rhodesians/Zimbabweans. The texts I have selected include a range of autobiographical and fictional writing, or memoirs and pseudo-memoirs, and I focus on form as a medium enabling an exploration of identity. The ways in which these authors conform to and adapt particular narratives of becoming is examined in each chapter, with a particular focus on the transition from innocence to experience, the autobiography, and the Bildungsroman. Gender is a recurring point of interest: in each case the female selves/protagonists are situated in terms of the family, which, in reflecting social values, is a key site of conflict. In regard to trends in white African writing, I explore the white African (farm) childhood memoir and the confessional mode. Ultimately I maintain that while the texts may be classified as white writing, as they are fundamentally concerned with white identity, and therefore evince certain limitations of perspective and form, including clichéd tendencies, all the writers interrogate white identity and the fictional texts more self-reflexively deconstruct tropes of white writing.
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  • Date Issued: 2013

Livelihood and coping strategy changes along rural-urban continua with an emphasis on natural resources

  • Authors: Evans, Michelle Leigh
  • Date: 2013
  • Subjects: Natural resources -- South Africa -- Queenstown Natural resources -- South Africa -- Phalaborwa Rural-urban divide -- South Africa -- Queenstown Rural-urban divide -- South Africa -- Phalaborwa Income -- South Africa -- Queenstown Income -- South Africa -- Phalaborwa Women heads of households -- South Africa -- Queenstown Women heads of households -- South Africa -- Phalaborwa Adjustment (Psychology)
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4731 , http://hdl.handle.net/10962/d1001958
  • Description: Rapid urbanisation is one of the greatest challenges facing both developed and developing countries. Sub-Saharan Africa has historically been one of the least developed and least urbanised areas of the world. However, urbanisation is now occurring much more rapidly in countries that have lower levels of per capita income. Therefore, in the coming decades, urban population growth is expected to be more widespread in the developing countries of the world. Most research on the role of natural resources focuses on rural communities and little is known about the contribution these resources make along the rural-urban continuum in small and medium sized towns as well as the contribution to total livelihoods. This is because researchers and policy makers have often treated rural and urban areas and their residents as distinct entities that should be studied in isolation. This, however, is not a true reflection of household livelihoods which often include both rural and urban elements. This study therefore analysed the impact of urbanisation on livelihoods along a rural-urban continuum with an emphasis on natural resources in South Africa. The main characteristics as well as the livelihood portfolios of respondent households were investigated. Secondly, the coping strategies used by households along the rural-urban continuum were explored, and disaggregated according to the gender of the household head. Data were collected along the rural-urban continuum of two small towns, namely Queenstown, located in the Eastern Cape province and Phalaborwa, located in the Limpopo Province of South Africa. Sampling covered the town, peri-urban areas, townships and adjacent rural households. A standardised survey instrument was used to capture household details and livelihood activities and a total of 272 interviews were conducted. The rural areas near both towns were poorer than the township and urban areas with regards to assets, access to employment and annual household income across all cash and non-cash income streams. The engagement in land-based activities increased towards the rural areas. The use of natural resources, as well as the number of resources collected, increased along the continuum towards the rural areas, with 12.0% to 49.0% of urban households, 30.0% to 88.0% of township households and between 80.0% and 100.0% of rural households engaging in the use and collection of natural resources. While natural resource use and collection was lowest in the urban areas, a significant amount of resources were still collected by urban households. Income portfolios for all households were calculated to determine the direct-use value of wild natural capital to livelihoods as well as the contribution made from land (arable and livestock farming), welfare grants and employment. Employment, barring one exception in the rural areas of Phalaborwa, was the largest contributor in terms of mean annual income along the continuum in both towns, followed by grants and pensions in the township and rural areas. In Phalaborwa, however, wild natural capital was found to be the largest contributor to local livelihoods, contributing 48.0% of the mean annual income. Household portfolios become more diversified in the poorer, rural areas as well as in households headed by females. The main shocks reported along the continuum in both Queenstown and Phalaborwa were death in the family, followed by a loss of employment, which was concentrated in male-headed households. Coping strategies resulting in the attainment of cash income fast, such as borrowing money from friends/relatives and cashing in retirements savings were favoured over longer term strategies such as finding local wage employment. Female-headed households were found to rely significantly on social groups or clubs as a coping strategy, highlighting the importance of social capital and social relations in female-headed households
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  • Date Issued: 2013

Evolution of the UG2 unit, Bushveld Complex, South Africa : mineral composition and petrological evidence

  • Authors: Everitt, Simon James
  • Date: 2013
  • Subjects: Textures -- South Africa -- Bushveld Complex Petrology -- South Africa -- Bushveld Complex Chromite -- South Africa -- Bushveld Complex Mineralogy -- South Africa -- Bushveld Complex
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4913 , http://hdl.handle.net/10962/d1001573
  • Description: Several disequilibrium textures are found to occur within the hanging wall and footwall of the UG2 chromitite layer of the Bushveld Complex, South Africa. These textures include plagioclase chadacrysts found included within orthopyroxene and clinopyroxene as well as the orthopyroxenes exhibiting round crystal boundaries that appear to be resorbed. Textures found within the UG2 stratigraphy such as linear boundaries and 120° triple junctions at interfaces of adjacent plagioclase or pyroxene grains also suggest that recrystallization has taken place. The presence of both disequilibrium textures and recrystallization textures would suggest that a complex emplacement history has occurred. Ideally, this would be expected to be manifested by minerals of the same type but which are texturally distinct showing different composition. However this has been found not to be the case; minerals that suggest disequilibrium textures show similar compositions to the minerals which appear to have formed in equilibrium. This is also the same for recrystallized crystals which show the same compositions as crystals that have not been recrystallized. For example tabular clinopyroxene, which has a compositional range of En 44.6 to En 50.5, is indistinguishable from clinopyroxene occuring as discontinuous rims, En 44.3-48.2, and as intergranular necking connecting primocrysts of orthopyroxene ( En 44.3-50.4). Similarly, plagioclase occurring as inclusions with An 66.3-76.0 is indistinguishable from plagioclase occurring as zoned or recrystallized interstitial grains ( An 69.0- An 77.4). Compositional variation has however, been found to be controlled to an extent by stratigraphy in that minerals show different compositions within one layer to the same minerals within another layer, consistent with an evolving magma composition. It is concluded therefore that while composition is not texturally controlled it is to an extent stratigraphy controlled and that the evidence collected within the study supports two models for the formation of chromite within the Bushveld complex. The evidence is consistent with a combination of the magma mixing model and magma injection model to account for the textures and compositional variations found within the study. The evidence may also show support for models involving late modification of minerals by magmatic fluids but not as prominently as for the models mentioned above , Microsoft� Word 2010 , Adobe Acrobat 9.53 Paper Capture Plug-in
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  • Date Issued: 2013

The isolation and characterisation of secondary metabolites from selected South African marine red algae (Rhodophyta)

  • Authors: Fakee, Jameel
  • Date: 2013
  • Subjects: Metabolites Marine algae -- South Africa Marine algae -- Therapeutic use Metabolites -- Therapeutic use Marine metabolites Plocamocera Red algae Laurencia Delisea flaccida
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:3733 , http://hdl.handle.net/10962/d1001472
  • Description: Secondary metabolites from natural sources are fast growing as popular drug leads. The structural novelty and favourable biological activity that these compounds display contribute to their popularity as drugs of the future. Examples of such compounds include the potent anticancer drug paclitaxel isolated from the bark of a yew tree as well as the more commonly known analgesic aspirin which stems from the bark of the willow tree. The biological activities exhibited by these secondary metabolites are vast and range from antimicrobial to anticancer activity to mention but a few. As a result, the isolation of novel compounds from natural sources is on the rise. The South African seaboard is home to a wealth of various marine algal species which produce fascinating secondary metabolites. For example, Portierria hornemanii was shown to produce halomon, a halogenated monoterpene which has displayed promising cytotoxic activity. This study thus focused primarily on pursuing novel compounds from three endemic South African marine algal species which have never been analysed previously from a chemical perspective. These are Plocamium rigidum (Bory de Saint-Vincent), Laurencia natalensis (Kylin) and Delisea flaccida (Suhr) Papenfuss. Four known compounds and one new halogenated monoterpene, (2E,5E,7Z)-8-chloro- 7-(dichloromethyl)-4-hydroxy-3-methylocta-2,5,7-trienal, were isolated from Plocamium rigidum. The breast cancer (MCF-7 cell line) inhibitory activity for these compounds was assessed and it was observed that an increase in the lipophilic nature of the compounds produced more favourable IC50 values. A pre-cursor to bromofucin type compounds, cis-laurencenyne, was isolated from Laurencia natalensis, as well as a new acetoxy chamigrane type compound, 4-bromo- 3,10-dichloro-7-hydroxy-3,7,11,11-tetramethylspiro [6.6] undec-1-yl acetate. Delisea flaccida was seen to contain two known bromofuranone type compounds isolated as an isomeric mixture, 1-[(5Z)-4-bromo-5-(bromomethylidene)-2-oxo-2,5- dihydrofuran-3-yl] butyl acetate and 1-[(5E)-4-bromo-5-(bromomethylidene)-2- oxo-2,5-dihydrofuran-3-yl]butyl acetate. These compounds are famous for their ability to inhibit bacterial biofilm production and they have been isolated before from an Australian Delisea spp , Adobe Acrobat 9.53 Paper Capture Plug-in
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  • Date Issued: 2013

Assessment of drug resistant Tuberculosis and Human Immunodeficiency Virus and Acquired Immunodeficiency Syndrome: knowledge levels among community members in Nelson Mandela Metropolitan Municipality

  • Authors: Fana, Thanduxolo
  • Date: 2013
  • Subjects: Multidrug-resistant tuberculosis -- South Africa -- Port Elizabeth , Tuberculosis -- South Africa -- Port Elizabeth -- Prevention
  • Language: English
  • Type: Thesis , Masters , MPA
  • Identifier: vital:8276 , http://hdl.handle.net/10948/d1016076
  • Description: The aim of this study was to assess community members’ knowledge levels regarding Drug Resistant TB and HIV and AIDS. The study was conducted at ward 40 in Green bushes area in Nelson Mandela Metropolitan Municipality (NMMM). A quantitative research method was used in this study. Random sampling is the type of probability sampling method that was used in this study. The sample consisted of 100 respondents above 18 years who were randomly selected from the beneficiary list of for the RDP houses in Green bushes area in the Nelson Mandela Metropolitan Municipality. Data for this study were collected using close ended questions which were administered by the researcher to the selected participants. Data was analysed using bivariate and descriptive statistics according to the identified themes. The study revealed that community members had high knowledge levels regarding Drug Resistant TB and HIV and AIDS prevention, transmission modes and diagnosis and treatment methods. The findings revealed that community members were highly knowledgeable and aware of the fact that abstaining and practising safe sex were means of preventing the spread of HIV and AIDS as it was spread through unprotected sex, while opening of windows and minimisation of close contact with HIV positive people and children with people infected with Drug Resistant TB are infection control measures or methods of preventing the spread of the disease. Additionally, the study indicated that female respondents were more aware and knowledgeable about prevention, transmission modes and diagnosis and treatment of Drug Resistant TB and HIV and AIDS than male respondents. Furthermore, the findings revealed that the respondents were highly knowledgeable and aware about transmission of Drug Resistant TB and HIV and AIDS; knowledgeable about prevention and less knowledgeable about diagnosis and treatment. A high percentage of female respondents knew that there was no vaccine to neither prevent nor cure HIV and AIDS and that antiretroviral drug were used to manage it. The study also showed that female respondents knew that all people irrespective of race and economic class can be infected with Drug Resistant TB and HIV and AIDS. It is important to note that the respondents between 41-60 years possessed more knowledge regarding Drug Resistant TB and HIV and AIDS than the respondents who were between 18-40 years. Lastly, the study showed that there were significant differences in gender and knowledge and no significant differences in age and knowledge of the respondents regarding Drug Resistant TB and HIV and AIDS. It is recommended that in future, research regarding knowledge levels about Drug Resistant TB and HIV and AIDS be extended to other wards in the Nelson Mandela Metropolitan Municipality (NMMM). Accurate knowledge should be provided by ensuring that educational materials that are developed, are appropriate for the various levels of literacy, and that more appropriate and relevant information regarding these diseases is made more accessible to community members in their home languages. The researcher further recommends that during training interventions and educational campaigns more emphasis should be put on prevention, diagnosis and treatment of Drug Resistant TB and HIV and AIDS.
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  • Date Issued: 2013

Endotracheal tube verification in the mechanically ventilated patient in a critical care unit

  • Authors: Fataar, Danielle
  • Date: 2013
  • Subjects: Respirators (Medical equipment) , Critical care medicine , Intensive care units
  • Language: English
  • Type: Thesis , Masters , MCur
  • Identifier: vital:10020 , http://hdl.handle.net/10948/d1008057 , Respirators (Medical equipment) , Critical care medicine , Intensive care units
  • Description: Critically ill patients often require assistance by means of intubation and mechanical ventilation to support their spontaneous breathing if they are unable to maintain it. Mechanical ventilation is one of the most commonly used treatment modalities in the care of the critically ill patient and up to 90% of patients world-wide require mechanical ventilation during some or most parts of their stay in critical care units Management of a patient’s airway is a critical part of patient care both in and out of hospital. Although there are many methods used in verifying the correct placement of the endotracheal tube, the need and ability to verify placement of an endotracheal tube correctly is of utmost importance, because many complications can occur should the tube be incorrectly placed. Since unrecognized oesophageal intubation can have many disastrous effects on patients, various methods for verifying correct endotracheal tube placement have been developed and considered. Some of these methods include direct visualization, end-tidal carbon dioxide measurement and oesophageal detector devices. This research study aimed to explore and describe the existing literature on the verification of endotracheal tubes in the mechanically ventilated patient in the critical- care unit. A systematic review was done in order to operationalize the primary objective. Furthermore, based on the literature collected from the systematic review, recommendations for the verification of the endotracheal tube in the mechanically ventilated patient in the critical care unit were made. Ethical considerations were maintained throughout the study and the quality of the systematic review was ensured by performing a critical appraisal of the evidence found.
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  • Date Issued: 2013

Propagating some commonly-used South African medicinal plants with compost and vermitea

  • Authors: Faulconbridge, Steven Craig
  • Date: 2013
  • Subjects: Medicinal plants -- Propagation -- South Africa , Compost -- South Africa
  • Language: English
  • Type: Thesis , Masters , MTech
  • Identifier: vital:10736 , http://hdl.handle.net/10948/d1020316
  • Description: The use of many of South Africa’s medicinal plants has shown marked increase with over 27 million users in South Africa alone. Most plants are still being unsustainably wild-harvested, a major concern for biodiversity conservation. Commercial interest in certain more commonly-used species has increased, with potential to cultivate medicinal plants on a more sustainable basis. Focus has shifted from conventional use of synthetic fertilisers, pesticides and fungicides to more organic methods of plant propagation. Aqueous extract derived from earthworm composted food waste (vermitea) was used to study the germination and rooting success of selected species. Also survival and growth performance of selected plants grown in a medium amended with commercial NPK fertiliser was compared to those grown in the same medium amended with compost and to those grown in the same medium amended with compost with weekly applications of vermitea. No change in germination success was noted. Vermitea showed promising results on the rooting of cuttings. The application of NPK improved growth performance (biomass) significantly for all species tested. However, they had lower root:shoot ratios as well as lower survival rates compared to plants under the compost and compost/vermitea treatments. The improved survival of these plants highlights the potential of these organic treatments on the propagation of selected medicinal plants.
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  • Date Issued: 2013

The development of platinum and palladium-selective polymeric materials

  • Authors: Fayemi, Omolola Esther
  • Date: 2013 , 2013-05-03
  • Subjects: Polymers , Platinum , Palladium , Adsorption , Sorbents , Nanofibers , Amines , Nanoparticles
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4287 , http://hdl.handle.net/10962/d1002964 , Polymers , Platinum , Palladium , Adsorption , Sorbents , Nanofibers , Amines , Nanoparticles
  • Description: The adsorption and separation of platinum(IV) and palladium(II) chlorido species (PtCl₆²⁻ and PdCl₄²⁻) on polystyrene-based beads and nanofibers as well as silica microparticles functionalized with polyamine centres derived from ethylenediamine (EDA), diethylenetriamine (DETA), triethylenetriamine (TETA) and tris-(2-aminoethyl)amine (TAEA) is described. The functionalized sorbent materials were characterized by using microanalysis, SEM, XPS, BET and FTIR. The nanofiber sorbent material functionalized with ethylenediamine (F-EDA) had the highest loading capacity which was attributed to its high nitrogen content (10.83%) and larger surface area (241.3m²/g). The adsorption and loading capacities of the sorption materials were investigated using both the batch and column studies in 1 M HCI. The adsorption studies for both PtCl₆²⁻ and PdCl₄²⁻ on the polystyrene-based sorbent materials fit the Langmuir isotherm while the silica-based sorbents fitted the Freundlich isotherm with R² values > 0.99. In the column experiment the highest loading capacity of Pt and Pd were 7.4 mg/g and 4.3 mg/g respectively on the nanofiber sorbent material based on ethylenediamine (EDA). The polystyrene and silica-based resins with triethylenetetramine (TETA) functionality (M-TETA and S-TETA) showed selectivity for platinum and palladium, respectively. Metal chlorido complexes loaded on the sorbent materials were recovered by using 3% m/v thiourea solution as teh eluting agent with quantitative desorption efficiency under the selected experimental conditions. The separation of platinum from palladium was partially achieved by selective stripping of PtCl₆²⁻ with 0.5 M of NaClO₄ in 1.0 M HCI with PdCl₄²⁻ was eluted with 0.5 M thiourea in 1.0 M HCI. The selectivity of the M-TETA and S-TETA sorbent materials was proved by column separation of platinum(IV) and palladium(II), respectively, from synthetic solutions containing iridium(IV) and rhodium(III). The loading capacity for platinum on M-TETA was 0.09 mg/g while it was 0.27 mg/g for palladium on S-TETA. , Acrobat PDFMaker 10.1 for Word , Adobe Acrobat 9.54 Paper Capture Plug-in
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  • Date Issued: 2013

Perceptions on ante-mortem welfare, quantitation of pain and pregnancy biomarkers, muscular fibre architecture and quality of Dohne Merino offal

  • Authors: Fayemi, Peter Olutope
  • Date: 2013
  • Subjects: Merino sheep , Slaughtering and slaughter-houses -- By-products , Biochemical markers , Meat -- Quality , Consumers' preferences , Cooking (Variety meats) , Livestock -- Transportation
  • Language: English
  • Type: Thesis , Doctoral , PhD (Animal Science)
  • Identifier: vital:11824 , http://hdl.handle.net/10353/d1007573 , Merino sheep , Slaughtering and slaughter-houses -- By-products , Biochemical markers , Meat -- Quality , Consumers' preferences , Cooking (Variety meats) , Livestock -- Transportation
  • Description: Sheep farming is practiced extensively in South Africa for its significant contributions to the livestock, wool and meat industries. The sheep farming sector in the country has approximately 13,800 farmers with commercial and communal sheep farmers making up 58 percent and 42 percent of the entire work force (Directorate of Agricultural Information Services, 2008). An estimate of 28.8 million sheep and flock size ranging between ≤ 50 and ≥ 1800 exist in various South African provinces. Although the national herd size is unevenly distributed provincially most of the herds are found in the Eastern Cape (30 percent) followed by the Northern Cape (25 percent), Free State (20 percent) and the Western Cape (11 percent) respectively (Agriculture, Forestry and Fisheries, 2011). Over twenty indigenous and locally developed sheep breeds are managed where about 69 percent of the land area is available for their grazing nation-wide (Campher et al., 1998; Palmer and Ainslie, 2006). Common among the indigenous breeds are the Afrikaner, Blackhead Persian, Blackhead Speckled Persian, Blinkhaar Ronderib, Damara, Karakul, Namaqua Afrikaner, Pedi, Redhead Persian, Redhead Speckled, Swazi and Zulu. The locally developed breeds include Dorper, Van Rooy and Merinos. The local breeds developed from Merinos consist of the Afrino, Dormer, Dohne Merino and South African mutton Merino (Hammond, 2000; Pranisha, 2004; Hinton, 2006; Sorma et al., 2012). All these sheep breeds are best suited for providing by-products such as wool, meat, hide, milk or a combination of products (Dave and Meadowcroft, 1996; Jensen, 2009). The indigenous and locally developed sheep were bred to meet the growing demand for its by-products (Peters et al., 2010). Expectedly, sheep farmers therefore, make use of the products from these sheep as a means of livelihood and sustenance of a viable local society (Cloete and Olivier, 2010).
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  • Date Issued: 2013

The effect of the Nelson Mandela Bay Stadium on surrounding house prices: a hedonic analysis

  • Authors: Fernandes, Gladys Nicola
  • Date: 2013
  • Subjects: Housing -- Prices -- South Africa -- Port Elizabeth , Stadiums -- Economic aspects -- South Africa -- Port Elizabeth
  • Language: English
  • Type: Thesis , Masters , MCom
  • Identifier: vital:9026 , http://hdl.handle.net/10948/d1020216
  • Description: Sports facilities increasingly feature amongst the most expensive development projects world-wide. One such facility includes world-class stadia. Such facilities tend to commit a considerably large amount of a country's public funds to the project. This public expenditure on new stadia, and the required public taxation, may be economically justified if the benefits from the new stadia outweigh the costs. 15 May 2004 saw South Africa winning the bid to host the FIFA 2010 Soccer World Cup tournament. This mega-event was played in 10 stadia across nine chosen host cities. Five of these stadia were newly constructed, while the other five needed upgrading. Both South Africa's national government and local governments of host cities bore the expenses of the new stadia construction and the upgrading to the existing stadia. This amounted to a total public expenditure of R13.5295 billion on the stadia alone. The Nelson Mandela Bay Stadium on the banks of the North End Lake in Port Elizabeth was amongst the five newly constructed stadia costing R1.7 billion. Many international studies have been conducted to assess the impact of new stadia on the economies of host cities. One particular aspect which has received a lot of attention as far as empirical research is concerned is the impact of stadia on residential property prices (Carlino & Couslon, 2004; Davies, 2005; Tu, 2005; Coates & Humphreys, 2006; Ahlfeldt & Maennig, 2007, 2010; Dehring, Depken & Ward, 2007; Feng & Humphreys, 2008, 2012; Kavetsos, 2010; Ahlfeldt, Maennig & Scholz, 2010; Kiel, Matheson & Sullivan, 2010; Ahlfeldt & Kavetsos, 2011; Coates & Matheson, 2011). The majority of the studies conducted have indicated that the presence of a new stadium in an area has a significantly positive effect on surrounding house values that decays with distance from the facility. As no study has yet been done in South Africa to investigate the impact of the announcement of the construction of new stadia on nearby residential property values, this study examines, by means of the hedonic pricing model, the effect of the announcement to construct the Nelson Mandela Bay Stadium on the banks of North End Lake on adjacent residential property values. The study period for this study was 2004 - 2006. This time period captured the stadium announcement effect. The residential properties in North End that were traded at least once during the period 2004 to 2006 made up the target population. According to the South African Property Transfer Guide (SAPTG), a total of 417 property transactions (excluding repeat sales) took place over the study period (2004 - 2006). The 417 transactions were deemed to be the size of the target population and a list of 100 property transactions were used as the sampling frame. As the study period was from 2004 - 2006, it was necessary to adjust the market prices to constant 2006 prices. For this purpose, data from the Port Elizabeth and Uitenhage section of the ABSA house price indices were used so as to eliminate any inflationary effects on the property values over the study period. The results of the study revealed that the stadium has a statistically significant positive effect on adjacent residential properties situated within a 1 200 metres radius from the stadium. The average owner of a residential property in North End would be willing-to-pay between R10 7898 and R11 704.6 to be situated 435 metres closer to the stadium.
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  • Date Issued: 2013

Development and validation of in-process control test kits for biodiesel production

  • Authors: Fibi, Pumza Oscarine
  • Date: 2013
  • Subjects: Biodiesel fuels -- South Africa , Biomass energy -- South Africa
  • Language: English
  • Type: Thesis , Masters , MTech
  • Identifier: vital:10416 , http://hdl.handle.net/10948/d1012645 , Biodiesel fuels -- South Africa , Biomass energy -- South Africa
  • Description: The production of biodiesel from vegetable oils is not a new technology; it has been around since the 1950’s and both the research in terms of the different feedstock that can be used and the production of biodiesel has since been gaining momentum as there needs to be a new, sustainable and domestic alternative to petroleum fuels. These petroleum fuels pose enormous threats to the environment and therefore need to be replaced as they are mostly contributing to climate change and global warming not to mention the frequent price hikes which are crippling the South African economy. Biodiesel production using vegetable oils seems to be and is the future and a law has recently been passed which sanctions the production of biofuel locally.[1] South African fuel producers will instigate obligatory blending of fossil fuel with biofuel as the country moves to encourage investment in its biofuels sector. The production of biodiesel locally and the blending of biodiesel with other petroleum products will reduce the country’s dependence on imported fuel. The already established petrochemical companies like BP, Sasol and Engine are therefore mandated to purchase these biofuels if and when the biofuels meet the required South African National Standard (SANS) 1935 requirements. This is then where the challenge comes as most of these growing biofuel companies cannot afford to purchase testing equipment.The growing companiesthen discover upon completion of the biofuel manufacturing process that their product does not meet the required standard specification. The failure translates to a financial loss as the final product can possibly not be reworked. The aim of the project is then to assist these companies who are manufacturing biofuel, by providing them with in-house biofuel process methods which will allow for early detection, should there be a need to redo a step in the process and not wait until the completion of the production process. These in-house process-testing methods will range from pH determination, titration tests which will determine the soap content and the percentage free fatty acid content, water determination, density and visual testing. It is not cost-effective for these biodiesel manufacturers to send their samples for outsource testing as evidently the results obtained would be out of specification hence the need to provide these biodiesel manufacturers with in-house analytical testing techniques that will aid in monitoring of the biodiesel production.
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  • Date Issued: 2013

The effectiveness in the administration of the national school nutrition programme in King Williams Town in the Eastern Cape

  • Authors: Fili, Linda Phinx
  • Date: 2013
  • Subjects: School children -- Food -- South Africa -- King William's Town -- Administration , Children -- Nutrition
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:9224 , http://hdl.handle.net/10948/d1020965
  • Description: Health and education are two important aspects of human capital and form the basis of an individual’s economic productivity in any country. In South Africa, hunger and malnutrition continue to hamper the health, quality of life and survival of school going children such that some children drop- out of school due to these socio-economic problems (Tomlinson,2007:2). The introduction of previous School Feeding Schemes to address the question of hunger and poverty within schools was mostly left in the 1980’s and 1990’s to charitable and Non-Governmental Organizations such as Operation Hunger and ITHUBA (Swartz, 2009:38). According to Perlman (1993:14) South Africa’s track record of child deaths was more than double that of any other country of similar income levels worldwide, due to the apartheid government deserting its responsibility of feeding the nation. The White Paper for the Transformation of Health System (1997: 125) had also stated that improving nutrition within the rural schools is an imperative and a sound economic investment which is politically rewarding. Nelson Mandela (1996:8) once said “Our children are our nation’s future. Prospects for development are seriously undermined by the kind of large scale deprivation of children that South Africa has experienced. On the other hand investing in their health, nutrition and education not only improves our children’s quality of life – the gains reverberate into the future generations. ” From April 1994, through the Reconstruction and Development Programme (RDP) the Government of National Unity under the leadership of Dr. Nelson Mandela identified the area of school feeding as a policy prime concern in redressing the imbalances and inequities of the past governments. Another initiative to redress the inequities of the past, was through the programme of Poverty Reduction which manifested itself in lack of income, lack of education and skills, lack of access to services and amenities and lack of ownership of land and housing (Public Service Commission, 2007.
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  • Date Issued: 2013

Exploring the challenges of income generating projects funded by the Department of Social Development at Kwa-Nobuhle, Uitenhage, in the Eastern Cape

  • Authors: Filita, Unathi Samora
  • Date: 2013
  • Subjects: Public investments -- South Africa -- Port Elizabeth , Economic development projects -- South Africa -- Port Elizabeth , Poverty -- South Africa -- Port Elizabeth -- Economic conditions
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:9191 , http://hdl.handle.net/10948/d1020323
  • Description: Income generating projects represent one strategy adopted by the Department of Social Development to alleviate poverty. The purpose of this study is to explore challenges of an income generating project funded by the Department of Social Development in Kwa-Nobuhle, Uitenhage of the Eastern Cape Province of South Africa., A sample of thirty respondents was drawn from ten income generating projects funded by the Department of Social Development. The sampling method of this study was purposive sampling. Data was gathered through semi-structured questionnaires. Related literature has been reviewed that focuses on income generating projects for poverty alleviation. Various recommendations have been made on the findings of the study. The findings of the study indicated the need for regular visits from the officials of the Department, to conduct monitoring and evaluation. Project members also need training on financial management so they cannot mismanage their finances. The research findings indicated clearly that strategies that were used by the Department were not effective enough to achieve desired goals of poverty alleviation.
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  • Date Issued: 2013

The criterion of justifiability as a ground for review following Sidumo v Rustenburg Platinum Mines (2007) 12 BLLR 1097 (CC)

  • Authors: Fischat, Herbert Robert James Falconer
  • Date: 2013
  • Subjects: Arbitration, Industrial -- South Africa , udicial review -- South Africa , Dispute resolution (Law) -- South Africa , Mineral industries -- South Africa -- Employees , Conflict of laws -- Labor laws and legislation -- South Africa
  • Language: English
  • Type: Thesis , Masters , LLM
  • Identifier: vital:10246 , http://hdl.handle.net/10948/d1019792
  • Description: This treatise will focus on the review of labour arbitration awards provided for under the oversight of the Commission for Conciliation, Mediation and Arbitration (CCMA), bargaining councils, statutory councils, accredited private agencies and approved private arbitration tribunals. The general grounds of review applicable to the arbitration awards of the different bodies are set out. Thereafter the case of Carephone (Pty) Limited v Marcus NO & others (1998) 19 ILJ 1452 (LAC) is analysed and the core principles pertaining to the justifiability test are clarified for the first time in the forum of the Labour Appeal Court. The judicial rationale for the relevance and applicability of the test to CCMA arbitration proceedings and criticisms of the test are examined. The justifiability tests are only applicable to review proceedings in CCMA matters and not available to private arbitration review matters. There are however three approaches which are being suggested for the application of the justifiability tests to private arbitration review. Firstly, it is suggested that the Arbitration Act could be interpreted to include the justifiability test under the statutory review grounds. Secondly, the arbitration agreements could be interpreted to include an implied term that the arbitrator is under a duty to give justifiable awards. Finally, it can be submitted that the law should be developed by reading into all arbitration agreements the ability to arbitrators to give justifiable awards. Since the judgment of Sidumo v Rustenburg Platinum Mines [2007] 12 BLLR 1097 (CC) various critical questions arose in relation to the interpretation and application for the purpose of dealing with subsequent review applications. Firstly, this research paper will seek to establish whether the courts in subsequent matters to the Sidumo judgment have interpreted reasonableness as a test or ground for review. Secondly the research paper will scrutinise case law whether the reviewing court is entitled to rely on and consider reasons other than those provided for by the commissioner in his award to determine inter alia, the reasonableness of his decision arrived at. The Constitutional Court in the Sidumo case rejected the so-called employer’s test, stating that ultimately the commissioner’s sense of fairness is what must prevail and not the employer’s view. Consequently an impartial determination whether or not a dismissal was fair is likely to promote labour peace amongst the labour force. The test arrived at by the Constitutional Court in the Sidumo case for determining whether a decision or arbitration award of a CCMA commissioner is reasonable, is a stringent test that will ensure that such awards are not easily interfered with. The question to be asked in determining whether there has been compliance with the standard is whether the decision of the commissioner is one which a reasonable decision maker could have reached. This approach will underpin the primary objectives of the Labour Relations Act which is the effective resolution of disputes. This finding will be apparent from important cases decided and discussed after the Sidumo landmark ruling.
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  • Date Issued: 2013

The medicinal plant Sutherlandia Frutescens regulates gene expression to reverse insulin resistace in rats

  • Authors: Fortuin, Melissa
  • Date: 2013
  • Subjects: Insulin resistance , Medicinal plants , Genetic regulation , Insulin resistance -- Animal models
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:10349 , http://hdl.handle.net/10948/d1020823
  • Description: Obesity can lead to Type 2 Diabetes, both conditions increase in association with physical inactivity and high-energy diets, resulting in elevated blood glucose, decreased insulin sensitivity and increased insulin resistance. Sutherlandia frutescens (S.frutescens), an anti-diabetic plant, reverses and prevents insulin resistance in a rat model and human cell culture model. Gene expression analysis in hepatocyte cultures, identified genes down regulated in insulin resistance and up regulated by S.frutescens. These included genes encoding vesicle transporter proteins, hypothesised to be linked to hepatic lipid accumulation and lipid droplet formation during insulin resistance. The aim of this study was to investigate critical genes involved in lipid droplet formation, vesicle assembly and transport in high fat diet (HFD)-induced insulin resistant rat liver tissue during the development of insulin resistance and the reversal of these changes by S.frutescens. Rats were fed a low fat diet (LFD) or HFD supplemented with S.frutescens for 2, 4 and 8 weeks. Rats fed a HFD for 12 weeks developed insulin resistance, confirmed by plasma glucose and insulin levels (compared to normal controls). Groups of these rats were gavaged with S. frutescens (50mg/kg BW), Metformin (13mg/kg BW) or water for a further 4 weeks and starved for 12 hours, anaesthetized and blood removed by heart puncture. Liver was stored in RNA-Later™ for qRT-PCR and snap-frozen in liquid nitrogen for western blotting and confocal microscopy analysis. Changes in expression of vesicle transporter genes VAMP3 and NSF were analysed by qRT-PCR and changes in the protein expression by western blotting analysis. Proteins were localised within the liver by confocal immunohistochemistry using ZEN lite™ software. Statistical analysis was performed using One-Way ANOVA and unpaired t-test. mRNA gene expression of vesicle transport components VAMP3, NSF and SNAP25 showed relatively moderate changes with considerable individual variation within control or experimental groups. Uncorrelated changes in mRNA and protein products were found and may be due to differential regulation by siRNA. Proteins also showed altered staining patterns in high fat diet rats that reverted towards normal on S. frutescens treatment, potentially reflecting functional changes associated with transport of lipid-filled vesicles.
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  • Date Issued: 2013

Single-end reflectometric measurements of polarization-mode dispersion in single-mode optical fibres

  • Authors: Fosuhene, Samuel Kofi
  • Date: 2013
  • Subjects: Fiber optics , Polarization (Light) , Optical measurements
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10948/6280 , vital:21069
  • Description: In this thesis two novel single-end methods are applied to measure and characterize polarization mode dispersion in single mode optical fibres. Polarization mode dispersion (PMD) is an important factor negatively affecting the successful implementation of high speed long haul optical fibre networks operating at bit rates of 10Gb/s and above. PMD measurements are thus important for quality control during manufacturing and cabling processes. It is also useful for network operators planning to upgrade bitrates in existing networks to 10Gb/s and beyond. In an optical fibre link, sections with particularly high PMD may act to increase the entire PMD of the link. Identifying and replacing such sections can greatly reduce the PMD of the link. PMD measurements can be forward or single-end. In forward measurements, both ends of the fibre are used for input and detection. In single-end configuration, only one end of the fibre is used. For this reason, single-end measurements are more practical for the field where fibre ends are situated several kilometres apart. Single-end techniques can be implemented with a continuous wave for non-local PMD measurements (by Fresnel reflection). If a pulsed wave is used, local measurements can be achieved (by total power due to Rayleigh scattering). Two single-end schemes, one based on Fresnel reflection and the other due to Rayleigh scattering have been applied to measure non-local and local PMD of standard single mode optical fibres. For the non-local PMD measurements, the general interferometric technique (GINTY) was modified to operate in a round-trip configuration. In this configuration, the fibre was treated as a concatenation of two identical fibre segments. Three different sets of fibres were investigated, each set representing a particular mode coupling regime. For polarization maintaining fibres, (PMFs), with no mode coupling, a factor of two was found between forward and single-end measurements. For long single mode fibres in the long length regime, the factor was 1.4. For a combination of PMF and single mode fibres, a factor of 1.6 was obtained. The method which is accurate, repeatable, low cost and robust is very suitable for field applications. The second method is the polarization optical time domain reflectometric (P-OTDR) technique. This technique performs local birefringence measurements by measuring the evolution of the states of polarization (SOP). The birefringence information from such measurements was extracted and analysed to characterise four different fibres. Beat lengths and correlation lengths extracted from the P-OTDR were used to calculate the differential group delay (DGD) of the fibres. Next an expression for the root-mean-square differential group delay was derived and applied to the birefringence measurements to calculate the DGDs at a single wavelength. This method which operates at a single wavelength has a huge advantage. Firstly it is able to measure completely all the fibre characteristic parameters. Secondly it can measure mean DGD, root mean square DGD and instantaneous DGD. A plot of instantaneous DGD vs. length enables one to identify and eliminate sections with particularly high DGD. Finally since the P-OTDR system operates with a single wavelength, real time monitoring of PMD is possible via multiplexing. The results obtained are repeatable, accurate and are in good agreement with the standard Jones Matrix Eigenanalysis (JME) technique.
  • Full Text:
  • Date Issued: 2013
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