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Improving job performance by using non-monetary reward systems to motivate low-skilled workers in the automotive component industry

  • Authors: Taljaard, Jacob Johannes
  • Date: 2002
  • Subjects: Employee motivation -- South Africa , Performance awards
  • Language: English
  • Type: Thesis , Masters , MBA
  • Identifier: vital:10910 , http://hdl.handle.net/10948/131 , Employee motivation -- South Africa , Performance awards
  • Description: Automotive component manufacturing companies where the labour is low skilled and the processes are labour intensive, are being challenged on a more regular basis to find methods to satisfy needs to motivate employees to improve performance. Automotive companies are becoming more under pressure to motivate employees through non-monetary rewards, due to collective bargaining which has made pay for performance very inflexible. It is because of this fact that employers have to assess non-monetary reward methods to motivate employees to improve performance. To be motivators, rewards must be aligned with the needs of people and the things that they value. If these rewards are aligned with employees needs, this could lead to increase in employee motivation, which will in turn lead to improvement in performance, and therefore lead to companies becoming more competitive. This research paper aims to assess what would be the motivators when establishing a non-monetary reward system. To this end the various motivational theories are presented which clearly identifies what needs people have and how they can be satisfied to change behaviour and therefore improve performance. Secondly, reward systems are discussed with various types of rewards being considered and more specifically non-monetary rewards. Applied research was undertaken to determine non-monetary rewards that will motivate low-skilled employees to improve performance. A survey, with the aid of a structured questionnaire, was used to gain information from 60 employees. The research was conducted in three companies that manufacture components for the auto industry. The majority of the respondents indicated that: 1. basic needs must be satisfied with monetary rewards; 2. non-monetary rewards, if linked to higher hierarchical needs, will then motivate employees; 3. non-monetary rewards should preferably be of a physical nature such as certificates, caps and t-shirts; 4. satisfaction of these higher level needs motivate employees and improve their performance; 5. employees prefer feedback and recognition as a non-monetary reward on a regular basis, and 6. the needs of employees should be identified through a survey to establish which rewards will satisfy these needs.
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  • Date Issued: 2002

Synthesis, properties and reactions of Novel Quinone Methides

  • Authors: Taljaard, Jana Heloïse
  • Date: 2007
  • Subjects: Quinone , Chemistry, Organic
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:10408 , http://hdl.handle.net/10948/616 , Quinone , Chemistry, Organic
  • Description: Novel p-quinone methides have been synthesized by the dealkylation of 5-(p-alkyloxyaryl)- 10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5-ols and related compounds. Aspects of the dealkylation reaction were investigated using computational methods in order to identify possible intermediates and postulate reasons for the observed reactivity patterns. This included studying the effect of varying the size of the central B-ring, changing the alkyloxy group, and altering the substitution pattern on the parent alcohols. We have assessed the relative energies of reaction intermediates and have also evaluated the influence of factors such as charge delocalisation, LUMO properties of the carbocations and thermodynamic factors on the dealkylation reaction. The use of different dealkylating reagents was also briefly investigated. Demethylation of 1,3- dimethyl-11-(4-methoxyphenyl)-6,11-dihydrodibenzo[b,e]oxepin-11-ol with pyridine hydrochloride led to acid-catalyzed ring-contraction of the parent alcohol to form a novel substituted anthraquinone, 9-(4-hydroxyphenyl)-1,3-dimethyl-anthracen-10-(9H)-one, in good yield. The general reactivity of the p-quinone methides of interest to us was explored by subjecting these compounds to reaction with a range of nucleophiles (bases, Grignard reagents and alcohols). A range of aryl Grignard reagents were reacted with the p-quinone methides, with the main product isolated in almost all cases being the aryl-coupled 1,2-addition product. The nucleophilic addition reactions of alcohols were supported by a computational study and a probable reaction mechanism has been postulated. A base-catalyzed rearrangement is proposed to account for the formation of products in which dehydrogenation of the ethane bridge was observed. These studies showed that in these p-quinone methides, chemical reactivity is strongly influenced by steric crowding, resulting in reversal of the normal 1,2- vs. 1,6- selectivities expected for nucleophilic addition. The ketalization process was explored further using diols and thiols. Products analogous to those obtained with the monohydric alcohols resulted from the diols, along with a series of novel bis-ethers. A range of miscellaneous reactions of 4-(dibenzo[a,d]cycloheptan-5-ylidene)cyclohexa-2,5,- dienone and related systems were investigated. Functionalization by epoxidation, dichlorocarbenation and Diels-Alder reactions, photochemical and [2+2] cycloaddition were attempted and reduction and oxidation reactions were also explored. Photochemical demethylation of an ortho-methoxyl substituent on the p-quinone methide system was observed to occur in good yield. The p-quinone methides underwent reductive coupling in the presence of Zn/AlCl3. The electronic spectra of highly conjugated carbocations were obtained and their potential as novel dyes evaluated. A low-temperature Grignard exchange reaction followed by spontaneous cyclization upon workup, was successful in synthesizing the lactone, spiro[10,11- dihydro-5H-dibenzo[a,d]cyclohepten-(3’,4’H)-phenyl-5,2’(5’H)-furan-5’-one], in one step from the starting ketone. A novel seven-membered Malachite Green dye analogue, 11-(4- dimethylamino-phenyl)-3-morpholin-4-yl-6,11-dihydro-dibenzo[b,e]oxepin-11-ol, was also synthesized and its electronic spectra compared to that of the unannulated Malachite Green dye series. All novel compounds synthesized were characterized using NMR, IR and HRMS-analysis.
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  • Date Issued: 2007

Using E-learning to support IT education in a university environment a case study approach

  • Authors: Taljaard, Marinda
  • Date: 2003
  • Subjects: Education, Higher -- South Africa -- Port Elizabeth -- Computer-assisted instruction , Internet in education , Information technology -- Study and teaching (Higher) -- South Africa -- Port Elizabeth , College teaching -- South Africa -- Port Elizabeth -- Computer network resources , University of Port Elizabeth
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:11091 , http://hdl.handle.net/10948/d1015740 , Education, Higher -- South Africa -- Port Elizabeth -- Computer-assisted instruction , Internet in education , Information technology -- Study and teaching (Higher) -- South Africa -- Port Elizabeth , College teaching -- South Africa -- Port Elizabeth -- Computer network resources , University of Port Elizabeth
  • Description: At the University of Port Elizabeth (UPE), the End User Computing course (EUC) acts as a service course for many departments. This implies that many students are forced by their curricula to register for this course. The ever-increasing numbers in EUC place a considerable load on existing human and physical resources. In lecture groups of 120 –160, students rarely get the attention they need, and the pace at which the content is delivered (too slow or too fast) may also inhibit the learning process. During an initial investigation into E-learning at UPE in 1999, a prototype virtual classroom was developed. There were, however, a number of problems with this prototype. Firstly, it was implemented using a number of different technologies, which made it difficult to extend and maintain. Secondly, it only addressed some aspects of an E-learning environment, which proved insufficient for the EUC course. In the existing EUC course at UPE, the students are already exposed to some E-learning concepts, as a section of their skills training component is handled by using multimedia software in a simulated environment. The objective of this project was to extend the E-learning component further to determine the advantages and disadvantages of using E-learning to support information technology (IT) education in a contact-university environment. This project included a literature search and survey of existing E-learning environments at other universities. This research was used to develop a draft framework for an E-learning environment. The framework was used to select a tool to create an E-learning environment at UPE. An experiment was designed using this E-learning environment to support two IT courses at different year levels. The results of the experiment were analysed using qualitative and quantitative methods to determine the impact of using E-learning to support IT education at UPE. The results of this research show that E-learning can be used to support IT education at UPE. More success, however, was achieved at postgraduate level than at first-year level. Making use of Elearning increased student satisfaction and promoted active learning, while providing benefits like convenience, communication, flexibility and scaffolding. We conclude, therefore, that E-learning can provide a flexible approach to IT education in a university environment in the future.
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  • Date Issued: 2003

An investigation into the development of environmental education as a field of practice in South African National Parks

  • Authors: Taljaard, Sandra
  • Date: 2009
  • Subjects: Environmental education -- South Africa National parks and reserves -- South Africa Environmental education -- Study and teaching -- South Africa
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1603 , http://hdl.handle.net/10962/d1003485
  • Description: This study looks at aspects of the development of environmental education in South African National Parks (SANParks), in relation to the emergence of national and organisational policy frameworks. In order to put current environmental education practices into context, the study firstly looks at the historical development line of environmental education in SANParks, as well as in the broader national context. This provides a framework within which the processes of change and development can be traced in terms of social, political and economic influences on an international and national front. The study finds that the promulgation of legislation, including the Constitution, National Acts and various other policies, reflected the trends of thinking and set the pace in a democratic South Africa, which led to the emergence of more explicit processes and refined policies. Popkewitz’s finding, that education emerged in modernity, is used in the study to illustrate this tendency. It finds that these changes in South Africa resulted in the establishment of more structured environmental education processes within SANParks, and led to the expansion, diversification and strengthening of environmental education as a field of practice over time. The study traces significant processes of recontextualisation of international and national environmental education related policies according to the framework established by Bernstein (1980). These processes of recontextualisation were followed in the formulation processes of SANParks policy and strategy documents in the period from 1999 to 2005, and resulted in an official pedagogic discourse for environmental education in SANParks. The study establishes a second level of recontextualisation, that is, the official pedagogic discourse of environmental education in SANParks is recontextualised to a pedagogic discourse of reproduction. The pedagogic discourse of reproduction relates to park practices, where contextualisation within park-based programmes appears to be strong. The park-based programmes resemble a ‘curriculum in practice’, which brings us to Cornbleth’s critical curriculum approach. The study utilises this approach to explore and explain the meaning of the critical perspective taken on curriculum construction and change efforts at park implementation level (Cornbleth, 1990). The study finds that the contextualisation of park programmes and practices lead to variety in park programmes, which adds richness to environmental education programmes and activities, and further highlights the fact that environmental education practices are prolific in national parks. The study also finds that historical and contextual processes associated with specific parks strongly characterise environmental education programmes and practices in those parks, and that partnership programmes, such as the Kids in Parks programme, contribute towards, and enhance the growth of environmental education as a specialised field of practice in SANParks. The study comments on the need for environmental education practices in SANParks to be reviewed and expanded in line with the contemporary approach towards the environment as a social construct of interacting components. These components include the biophysical, social, economic and political dimensions. The study also highlights the need for the recognition and acknowledgement of the long, historical development line of environmental education in SANParks in order to build on established structures in a holistic way. The study further determines a need for strong leadership to successfully expand this specialised field of practice and encourages a participatory approach in the review and further development of this field of practice in SANParks. The study ultimately finds that environmental education in SANParks has a long and rich development profile, which has placed it in a strong position for further development. However, it concludes that there is a great need for a rejuvenated approach, which requires expert knowledge, professionalism and broad based networking approach to enable meaningful expansion within this specialised field of practice.
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  • Date Issued: 2009

Block copolymer templates for metal oxide nanostructures

  • Authors: Talla, Assane
  • Date: 2019
  • Subjects: Nanotechnology , Nanostructured materials Metal oxide semiconductors
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10948/43889 , vital:37075
  • Description: Recent advances in technology have increased the need for fabrication of devices with feature sizes of tens of nanometers, such as ultra-fine filters or membranes, and high density data storage media, to name a few. For this reason, research is now focused on block copolymer nanolithographic processes, particularly the fabrication of nanoscale templates with domains well below 100 nm. Block copolymers have the tendency to self-organise into various structures, such as lamellae, spheres or cylinders on a nanometer scale. Among these possible configurations, the perpendicular cylindrical structure is most desirable, because it can be used for templates or masks for feature development, in particular, oriented wires or rods. In this work, the aim is to create a nano-mask from a di-block copolymer thin film, for zinc oxide nanorods growth. For this purpose poly (styrene-block-methylmethacrylate) (PS-b-PMMA) was investigated as a potential nano-mask. Samples were characterized using X-ray reflectometry to determine the thicknesses of the PS-b-PMMA thin films, while scanning probe microscopy and scanning electron microscopy was used to investigate the surface morphology of the samples. PS-b-PMMA thin films were produced on a random copolymer (poly (styrene-random-methylmethacrylate) (PS-r-PMMA) coated onto a silicon substrate. The PS-r-PMMA permits a non-preferential interaction between the di-block constituents and the substrate. Thermal annealing in vacuum of PS-b-PMMA on PS-r-PMMA led to perpendicular cylinders of PMMA within a PS matrix in the di-block. The typical thicknesses measured for the di-block copolymer films ranged between 33 nm and 37 nm. During this study, a perpendicular orientation of the di-block components was also produced when PS-b-PMMA was spun onto a layer of zinc oxide nanoparticles and thermally annealed in vacuum. It was shown that the ZnO nanoparticles created a corrugated surface on silicon which induced perpendicular cylinders of PMMA within the PS matrix. This was possible for a specific surface roughness parameter and film thickness. In this case, the typical thickness determined for the di-block copolymer ranged between 33 and 35 nm and the surface roughness parameter was 0.07. For the fabrication of a di-block template or PS nano-mask, the vertically oriented PMMA cylindrical nanodomains in the PS matrix were removed by exposing the film to ultraviolet radiation at an adequate dose, followed successively by washing in acetic acid and de-ionized water. It was shown that ultraviolet exposure is necessary to ensure the degradation of PMMA. A subsequent rinse in glacial acetic acid and DI water of the film exposed to ultraviolet, left an array of ordered nanoscopic pores with sizes ranging between 10 nm and 20 nm. Finally, the growth of ZnO nanorods on the di-block template produced on zinc oxide nanoparticles, was attempted using an aqueous solution based-method, namely chemical bath deposition. The rods did not grow inside the nanopores, probably due to poor capillary action. In additional experiments, the di-block template was removed by toluene (a selective solvent for PS) followed by the growth of ZnO rods on the exposed nanoparticle surface. Vertical and well separated ZnO rods formed on this surface, in places where the underlying seed layer had been attacked by the acetic acid treatment during removal of the PMMA. The observed ZnO rod morphology can be used in applications such as solar cell.
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  • Date Issued: 2019

Development of MgZnO-grown MOCVD for UV Photonic applications

  • Authors: Talla, Kharouna
  • Date: 2011
  • Subjects: Photoluminescence , Photonics , Zinc oxide
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:10537 , http://hdl.handle.net/10948/d1012585 , Photoluminescence , Photonics , Zinc oxide
  • Description: MgxZn1-xO has emerged as a material of great technological importance. Having a direct energy band gap that is tunable throughout much of the ultraviolet (UV) region of the spectrum from the near-UV (~370 nm) to the deep-UV (~176 nm), this compound is of interest for a variety of optoelectronic devices operating in this part of the electromagnetic spectrum. MgxZn1-xO offers advantages over the more mature compound semiconductor AlGaN which stem mainly from the unusually high exciton binding energy (60 meV in ZnO). In this study the growth of ZnO and MgxZn1-xO thin films using metal organic chemical vapour deposition (MOCVD) is systematically investigated. The films are mainly grown on c-Al2O3 and Si (100) and characterized using various techniques, such as photoluminescence (PL), x-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and auger electron spectroscopy (AES). The optical and the structural properties are essentially inspected in order to improve their quality. In this thesis the optimisation of ZnO grown using oxygen gas as a new oxidant in our reactor is investigated. The growth temperature and VI/II ratio are varied in order to find optimum parameters giving high quality layers. The effects of Si (100), Si (111), c- and r-sapphire, glass, GaAs and ZnO substrates on the optical, structural and morphological properties of ZnO thin films grown with tert-butanol (TBOH) is examined. Similar morphologies are observed for all substrates, with the films comprising hexagonal columns having cone shaped ends. The photoluminescence spectra are similar, but the various transitions have different relative intensities. It is clear that the different substrates influence neither the orientation of the films, nor the surface morphology, significantly. The photoluminescence hints at larger stacking fault densities in films grown on silicon and glass, however, as evidenced by stronger basal plane stacking fault-related luminescence at ~3.319 eV in the relevant low temperature photoluminescence spectra. The morphology changes with Mg incorporation, from hexagonal columnar structures to cubic faceted columns. From PL, the full with at half maximum is found to gradually increase with Mg content due to alloy broadening. The deep level emission (DLE) is observed to shift with Mg content. By changing the Mg content, the band gap of MgxZn1-xO film is tuned by ~450 meV, which provides an excellent opportunity for band gap engineering for optoelectronic applications. The c-lattice constant of ZnO (5.205 Å) decreases by only 0.6% when the Mg content reaches x=0.39. The introduction of Mg into ZnO is shown to increase the relative PL intensity of stacking fault-related transitions (at 3.314 eV for ZnO). This becomes the dominant near band edge emission. Using TEM a thin Mg rich layer is observed at the interface between the film and the Si or Al2O3. Temperature dependent PL measurements on layers with low Mg concentration (x=0.05 and 0.1) show that the main bound exciton peak exhibits an “s-shaped” temperature dependence, characteristic of localization in a disordered alloy. The origin of the PL line broadening of MgxZn1-xO (x≤0.04) is also analyzed with respect to alloy broadening, taking into account a random cation distribution and alloy clustering. The influence of various MOCVD growth parameters such as growth temperature and VI/II ratio is studied. Varying the temperature from 280 ˚C to 580 ˚C reveals strong morphological changes and optical degradation of the films. Low (<280 ˚C) and high (>580 ˚C) growth temperatures reduce the Mg incorporation. High VI/II ratios also decrease the Mg incorporation, as evidenced by the red-shift of the donor bound exciton (D°X) line. This is ascribed to a stronger premature reaction between (MeCp)2Mg and the oxidant or a preferential heterogeneous interaction between the Mg and oxygen species on the growth front. For both oxidizing agents (O2 and TBOH), the growth at 420 ˚C and a VI-II ratio of 60 on c-Al2O3 gave optimal quality layers in terms of their optical and structural quality. A comparison of films grown using TBOH and O2 gas as oxidizing agent shows no major difference in terms of Mg incorporation. The effect of annealing, the inclusion of a buffer layer and the influence of growth rate on the properties MgxZn1-xO thin films are also reported.
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  • Date Issued: 2011

Genetic connectivity of the roundjaw bonefish (Albula glossodonta) in the Southwest Indian Ocean

  • Authors: Talma, Sheena Claudia Aisa Lydie
  • Date: 2021-10-29
  • Subjects: Bonefish Mauritius , Bonefish Seychelles , Bonefish Genetics , Bonefish Habitat , Bonefish Geographical distribution , Bonefish Larvae Dispersal , Genetic markers , Cytochrome b , Fish populations Mauritius , Fish populations Seychelles , Marine ecotourism , Saltwater fly fishing , Bonefish fisheries Catch effort
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10962/192174 , vital:45202
  • Description: The Southwest Indian Ocean (SWIO) islands of Mauritius and Seychelles are both highly dependent on tourism and fisheries for their economies. One of the growing ecotourism sectors is saltwater fly fishing, an industry based on catch-and-release fishing for a host of species, including bonefishes. Bonefishes (Albula spp.) have received significant research attention in the Pacific and Atlantic Oceans, with only sporadic research conducted in the Indian Ocean. My project aimed to investigate the genetic connectivity of the roundjaw bonefish (Albula glossodonta) in two island states (Seychelles and Mauritius) within the SWIO using a mitochondrial genetic marker (cyt-b) and next generation sequencing (ddRADseq). Samples collected were grouped based on their spatial distribution. The Seychelles consisted of four island groups (Inner Island Group, Aldabra Group, Amirantes and Alphonse Group, and Farquhar Group) whereas Mauritius was represented by one island group (Saint Brandon). Genetic analyses were undertaken between and within each of these groups. Mitochondrial cytochrome-b identified two species of bonefish: Albula glossodonta and Albula oligolepis; the latter was only genetically identified from the Inner Island Group. I hypothesise that this is due to habitat partitioning, with A. oligolepis being a deeper dwelling bonefish species compared to A. glossodonta, which occupies shallow water habitats such as sand flats, atoll lagoons and reef flats. Neutral SNP loci revealed a panmictic pattern of distribution for A. glossodonta throughout the Seychelles Island groups but showed a pattern of weak structure between Seychelles and Mauritius. Genetic diversity indices such as allelic richness, showed low diversity across the sampling sites (AR range: 1.761-1.889). Population structure tests such as pairwise FST showed low but significant population structure. The highest FST indices were recorded between the Aldabra and Farquhar Groups, as well as the Aldabra and Saint Brandon Groups (0.044 ± 0.000 and 0.040 ± 0.000, respectively). Descriptive tests such as PCA and DAPC showed similar trends, whereby Saint Brandon clustered separately from the other samples from the Seychelles Island groups. However, these trends were Abstract seen at very low variations (PCA axes 1 and 2 accounted for only 2.0 and 1.9 % of the total variation, respectively). A population assignment test grouped the individuals as one ancestral population. A spatial principal component analysis showed that Saint Brandon was dissimilar to the Seychelles Island groups. Like other Elopomorph species, bonefishes have leptocephalus larvae capable of long-distance dispersal which may explain the well-mixed genetic population observed within the Seychelles islands. Although currents within the Indian Ocean, especially on a mesoscale, are not well understood, the South Equatorial Current likely facilitates connectivity between the Seychelles islands while also limiting gene flow between Seychelles and Mauritius. Understanding population structure is important for informing the appropriate management and conservation strategies, especially in oceanic nations where data informing important industries like tourism and fisheries are often limited. The bonefish fly fishing industry is well-known to be a lucrative sector, generating, for example US$ 1.4 million a year in the Bahamas. This study recognised that there are numerous knowledge gaps relevant to the bonefish industry that need to be addressed, including: 1) understanding the socio-economic importance of fly fishing to island states like Seychelles, 2) estimating the abundance and species distribution of bonefishes within Seychelles, 3) understanding effectiveness of MPAs for recreational fishery species like bonefish and, lastly, 4) generating more fishery-relevant biological information on the heavily targeted fly fishing species within Seychelles. These needs must be met to inform management plans and to better manage the fly fishing ventures that target species like bonefish. , Thesis (MSc) -- Faculty of Science, Ichthyology and Fisheries Science, 2021
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  • Date Issued: 2021-10-29

The principle of inclusion-exclusion and möbius function as counting techniques in finite fuzzy subsets

  • Authors: Talwanga, Matiki
  • Date: 2009
  • Subjects: Fuzzy logic , Fuzzy sets , Fuzzy systems , Möbius function
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5413 , http://hdl.handle.net/10962/d1005227 , Fuzzy logic , Fuzzy sets , Fuzzy systems , Möbius function
  • Description: The broad goal in this thesis is to enumerate elements and fuzzy subsets of a finite set enjoying some useful properties through the well-known counting technique of the principle of inclusion-exclusion. We consider the set of membership values to be finite and uniformly spaced in the real unit interval. Further we define an equivalence relation with regards to the cardinalities of fuzzy subsets providing the Möbius function and Möbius inversion in that context.
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  • Date Issued: 2009

Counting of finite fuzzy subsets with applications to fuzzy recognition and selection strategies

  • Authors: Talwanga, Matiki
  • Date: 2015
  • Subjects: Möbius transformations , Fuzzy sets , Functions, Zeta , Partitions (Mathematics)
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:5431 , http://hdl.handle.net/10962/d1018186
  • Description: The counting of fuzzy subsets of a finite set is of great interest in both practical and theoretical contexts in Mathematics. We have used some counting techniques such as the principle of Inclusion-Exclusion and the Mõbius Inversion to enumerate the fuzzy subsets of a finite set satisfying different conditions. These two techniques are interdependent with the M¨obius inversion generalizing the principle of Inclusion-Exclusion. The enumeration is carried out each time we redefine new conditions on the set. In this study one of our aims is the recognition and identification of fuzzy subsets with same features, characteristics or conditions. To facilitate such a study, we use some ideas such as the Hamming distance, mid-point between two fuzzy subsets and cardinality of fuzzy subsets. Finally we introduce the fuzzy scanner of elements of a finite set. This is used to identify elements and fuzzy subsets of a set. The scanning process of identification and recognition facilitates the choice of entities with specified properties. We develop a procedure of selection under the fuzzy environment. This allows us a framework to resolve conflicting issues in the market place.
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  • Date Issued: 2015

Women and co-operatives

  • Authors: Tame, Faith Jabulile Nomfundiso
  • Date: 2017
  • Subjects: Cooperative societies -- Women -- South Africa -- Eastern Cape Women in agriculture -- South Africa -- Eastern Cape , Agriculture -- Social aspects -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10948/20615 , vital:29358
  • Description: In this study, “Women and Cooperatives”, the researcher was interested in finding out whether women cooperatives contributed towards development of women and poverty reduction in Sarah Baartman District Municipality between 2004 and 2014. The study was conducted with three cooperatives situated in Makana Local Municipality, Sarah Baartman District Municipality and Eastern Cape Province. The cooperatives studied focused on sewing, poultry and agriculture. The study was explorative in nature as it was aimed at assessing the effectiveness of women cooperatives in empowering women, the effectiveness of women cooperatives in reducing poverty and to make recommendations regarding what can be done to address the challenges identified in the study. The qualitative research method was applied when conducting this study. Eight respondents from each cooperative were willing to take part and this led to a total of twenty-four respondents who participated. The questions asked were based on the interview schedule developed by the researcher. The results of the study and the recommendations indicated that more commitment from the government is required and the following key aspects should be taken into account when considering a development program: Infrastructure, Availability of funding, Access to resources, Skills development, Provision of basic services.
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  • Date Issued: 2017

High school teachers' experiences of dealing with learners made vulnerable by HIV and AIDS

  • Authors: Tame-Gwaxula, Sindiswa Ruby , De Lange, Naydene
  • Date: 2014
  • Subjects: Educational counseling , High school teachers , HIV-positive persons -- Care , Communicable diseases in children
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: http://hdl.handle.net/10948/2959 , vital:20377
  • Description: The HIV and AIDS pandemic have become not only a health concern but educational and social concern as well. According to Beyers and Hay (2011, p. 99) many school-going children are not only affected by HIV but a large number of adolescents are also either HIV positive or have AIDS. Other researchers argue that education should act as a vaccine against new HIV infections (Kendall and O’Gara, 2007, p. 6). This argument comes with the expectation that all teachers are willing and ready to work with learners made vulnerable by HIV and AIDS; without considering the lived realities of the teachers in relation to HIV and AIDS. While many teachers make a difference in the lives of affected and infected learners through the way in which they deal with the learners concerned, some may not take up the challenge to assist the learners, while others might unknowingly and unintentionally do harm. This study, therefore, aimed at exploring high school teachers’ experiences of working with learners made vulnerable by HIV and AIDS in order to generate guidelines to assist teachers to effectively deal with vulnerable learners in their classrooms.
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  • Date Issued: 2014

Cooperative wasp-killing by mixed-species colonies of honeybees, Apis cerana and Apis mellifera

  • Authors: Tan, K , Yang, M-Y , Li, H , Zhang, Z-L , Radloff, Sarah E , Hepburn, H Randall
  • Date: 2012
  • Language: English
  • Type: text , Article
  • Identifier: vital:6838 , http://hdl.handle.net/10962/d1010979 , http://dx.doi.org/10.1007/s13592-011-0098-5
  • Description: The cooperative defensive behaviour of mixed-species colonies of honeybees, Apis cerana and Apis mellifera, were tested against a predatory wasp, Vespa velutina. When vespine wasps hawk honeybees at their nest entrances, the difference in the numbers of bees involved in heat-balling among pure species and mixed-species colonies was not significantly different. However, in the mixed colonies, the numbers of A. cerana and A. mellifera workers involved in heat-balling were significantly different. The duration of heat-balling among these three groups was significantly different. During heat-balling, guard bees of both species in mixed colonies raised their thoracic temperatures and the core temperatures of the heat-balls were about 45°C, which is not significantly different from that of the pure species. These results suggest that the two species of honeybees can cooperate in joint heat-balling against the wasps, but A. cerana was more assertive in such defence.
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  • Date Issued: 2012

Intra- and interspecific brood recognition in pure and mixed-species honeybee colonies, Apis cerana and A. mellifera

  • Authors: Tan, K , Yang, M-X , Radloff, Sarah E , Yu, Y , Pirk, C W W , Hepburn, H Randall
  • Date: 2009
  • Subjects: Apis mellifera Apis cerana
  • Language: English
  • Type: text , Article
  • Identifier: vital:6837 , http://hdl.handle.net/10962/d1010962 , http://dx.doi.org/10.1051/apido/2009003
  • Description: We studied the effects of mixed honeybee colonies of Apis mellifera and Apis cerana on the intraspecific and interspecific recognition of female brood stages in the honeybees A. cerana and A. mellifera by transferring brood combs between queenright colonies. In the intraspecific tests, significantly more larvae were removed in A. cerana than in A. mellifera, whilst significantly fewer eggs and pupae were removed in A. cerana than in A. mellifera. In the interspecific tests, A. cerana colonies removed significantly more larvae and pupae of A. mellifera than the same brood stages of A. cerana were removed by A. mellifera. We show there are highly significant differences in both intraspecific and interspecific brood recognition between A. cerana and A. mellifera and that brood recognition operates with decreasing intensity with increasing developmental age within species. This suggests that worker policing in egg removal is a first line of defense against heterospecific social parasites.
  • Full Text: false
  • Date Issued: 2009

Bee-hawking by the wasp, Vespa velutina, on the honeybees Apis cerana and A. mellifera

  • Authors: Tan, K , Radloff, Sarah E , Li, J J , Hepburn, H Randall , Yang, Ming-Xian , Zhang, L J , Neumann, Peter
  • Date: 2007
  • Language: English
  • Type: text , Article
  • Identifier: vital:6941 , http://hdl.handle.net/10962/d1011965
  • Description: The vespine wasps, Vespa velutina, specialise in hawking honeybee foragers returning to their nests. We studied their behaviour in China using native Apis cerana and introduced A. mellifera colonies. When the wasps are hawking, A. cerana recruits threefold more guard bees to stave off predation than A. mellifera. The former also utilises wing shimmering as a visual pattern disruption mechanism, which is not shown by A. mellifera. A. cerana foragers halve the time of normal flight needed to dart into the nest entrance, while A. mellifera actually slows down in sashaying flight manoeuvres. V. velutina preferentially hawks A. mellifera foragers when both A. mellifera and A. cerana occur in the same apiary. The pace of wasp-hawking was highest in mid-summer but the frequency of hawking wasps was three times higher at A. mellifera colonies than at the A. cerana colonies. The wasps were taking A. mellifera foragers at a frequency eightfold greater than A. cerana foragers. The final hawking success rates of the wasps were about three times higher for A. mellifera foragers than for A. cerana. The relative success of native A. cerana over European A. mellifera in thwarting predation by the wasp V. velutina is interpreted as the result of co-evolution between the Asian wasp and honeybee, respectively.
  • Full Text:
  • Date Issued: 2007

Electrospun nanofibers as solid phase extraction sorbents and support for alkylphenols colorimetric probes

  • Authors: Tancu, Yolanda
  • Date: 2014
  • Subjects: Nanofibers , Electrospinning , Extraction (Chemistry) , Sorbents , Phenols , Colorimetry , Transmission electron microscopy , High resolution spectroscopy
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:4486 , http://hdl.handle.net/10962/d1012997
  • Description: The thesis reports on fabricating alternative solid phase extraction (SPE) sorbents and colorimetric probes based on electrospun nanofibers for alkylphenols (APs). Hydroxyl methylated styrene [poly(co-styrene-CH₃OH)] and 3-oxobutanoate styrene [poly(co-styrene-OCOCH₃COCH₃)] copolymers were synthesized and fabricated into sorbent materials by electro-spinning/spraying. The fabricated morphologies consisting of bead free fibers, beaded fibers and particles were evaluated as SPE sorbents using batch experiments. Electropun fibers proved to be better sorbents as they exhibited extraction efficiency that exceeded 95% compared to 60% for beaded fibers and 40% for particles. In view to reduce sample and solvent volumes, smooth fibers were packed into pipette tips as SPE devices that yielded quantitative recoveries of APs from spiked wastewater samples. Recoveries ranged from 70% to 125% with LOD of 0.008, 0.01 and 0.1 μg mL⁻¹ for 4-tert octylphenol (4-t-OP), 4-octylphenol (4-OP) and 4-nonylphenol (4-NP) respectively, when using high performance liquid chromatography-fluorescence detector (HPLC-FLD). Furthermore, amino functionalised polydiacetylene polymers (PDAs), citrate capped gold (AuNPs) and silver nanoparticles (AgNPs) were evaluated as colorimetric probes for visual detection of APs. In colloidal studies, AuNPs probe showed a colour change from wine red to green upon introduction of analyte. UV-vis spectroscopy revealed the shifting of the surface plasmon resonance (SPR) peak from 525 nm to 729 nm induced by aggregation of AuNPs. For AgNPs probe, a colour change was observed from yellowish green to brown. Transmission electron microscopy (TEM) studies showed growth of AgNPs. A presumed oxidation of the analyte, forming an absorbing compound at 279 nm in both AgNPs and PDAs probes was also observed. For PDAs probe the colour change was from purple to pink. Concentrations as low as 30 μg mL⁻¹ were detectable in all colloidal based probes. Further colorimetric investigations were conducted with electrospun AuNPs-nylon 6 fiber mat. A colour change from purplish red to navy blue at concentrations of 1000 μg mL⁻¹ was observed. Electrospun AgNPs –nylon 6 fiber mat did not show a distinct colour change. High resolution scanning electron microscopy (HRSEM) revealed the analyte inducing the assembly of AuNPs and AgNPs as they covered the surface of the nanofiber mat. Electrospun nanofibers are a platform for analysis and thus tuning their chemistry will lead to sensitive and selective methods
  • Full Text:
  • Date Issued: 2014

The effect of 6-Methoxy-2-Benzoxazolinone (6-MBOA) on indoleamine regulation and its possible role in depression

  • Authors: Tanda, Sindiswa Eunice
  • Date: 2000
  • Subjects: Tryptophan -- Physiological effect , Tryptophan -- Therapeutic use , Antidepressants
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:3912 , http://hdl.handle.net/10962/d1003971 , Tryptophan -- Physiological effect , Tryptophan -- Therapeutic use , Antidepressants
  • Description: Tryptophan is an essential amino acid that is obtained from the diet. Approximately 98 % of ingested tryptophan is metabolized by the enzyme tryptophan 2,3-dioxygenase (TDO). The metabolism of tryptophan by TDO is an important determinant of tryptophan bioavailability to the brain for serotonin (5-HT) biosynthesis, an essential amine in affective disorders such as depression. Studies done on circadian rhythmicity of the enzyme activity have shown that, TDO activity is high during the scoto-phase (dark-phase), which is attributable to the de novo enzyme synthesis that occurs during this phase. 6-Methoxy-2-benzoxazolinontr-(6-MBOA), a structural analogue of melatonin (aMT) was shown to inhibit TDO activity in both the photo-phase (light-phase) and the scoto-phase with greater potency during the light-phase. Further studies were directed at demonstrating the effects of 6-MBOA on the brain tryptophan hydroxylase (TH) activity, which is a rate limiting enzyme in 5-HT biosynthesis and subsequently on 5-HT levels. The findings showed that, 6-MBOA induces TH activity with a concomitant rise in brain 5-HT levels. The blockade of 5-HT re-uptake into the presynaptic neuron leads to an increase in 5-HT available for the stimulatory action of 5-HT receptors. An attempt to establish whether the administration of 6-MBOA would block the binding of 5-HT to receptors on the synaptosomal membrane showed that 6-MBO A only inhibits the binding of 5 -HT at specific concentrations. In view of the positive effects imposed by 6-MBOA on brain 5-HT levels, urinary 5-hydroxyindole acetic acid (5-HIAA) excretion was measured before and after treatment with 6-MBOA. 5-HIAA excretion was found to be significantly increased after 6-MBOA treatment. Extensive research on the biosynthesis of pineal metabolites has been conducted in the past two decades. The pineal metabolites are synthesized from the precursor tryptophan. In order to obtain an overall picture of the effect of6-MBOA on pineal indole metabolism, an organ culture technique was employed. The results obtained showed that although 6-MBOA administration to rats caused a significant increase in aMT production, there was an insignificant increase in NAS production. This is an immediate precursor of aMT. Other pineal indoles were not affected at all by 6-MBOA administration. Furthermore, the production of pineal NAS and aMT showed an inter-individual variation with some animals producing very high, some very low and some produced average levels of these two metabolites in both photo and scoto-phase experiments. A study undertaken to investigate the circadian rhythm in endogenous aMT production using the competitive ELISA technique showed a clear pattern with high levels of aMT produced during the dark-phase and low levels ofaMT produced during the light-phase. Furthermore, the administration of6-MBOA to rats lead to a significant rise in endogenous aMT production.
  • Full Text:
  • Date Issued: 2000

The Influence of Clientelism on the Informal Sector in Zimbabwe : a Case Study of Glen View 8 Complex, Harare

  • Authors: Tandire, Justin
  • Date: 2021-04
  • Subjects: Patron and client -- Zimbabwe -- Harare , Informal sector (Economics) -- Zimbabwe -- Harare , Informal sector (Economics) -- Political aspects -- Zimbabwe -- Harare , Patronage, Political -- Zimbabwe -- Harare , ZANU-PF (Organization : Zimbabwe) , Zimbabwe -- Social conditions , Glen View Complex 8 (Zimbabwe)
  • Language: English
  • Type: thesis , text , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/177986 , vital:42896 , 10.21504/10962/177986
  • Description: This study focuses on the influence of clientelism in the informal sector of Zimbabwe in Glen View 8 (Complex). The study used the case of Glen view 8 (complex) in Harare Province. The study focused on political dynamics in the informal sector; livelihood strategies employed by informal sector operators; manifestation of “Big Men”, social networks in the informal sector; and different strategies employed by operators to overcome the problems of political manipulation, clientelism and patronage. It employs a qualitative research methodology to enable a nuanced comprehension of the clientelistic relationships that take place in the informal sector of Zimbabwe. Through in-depth interviews, focus group discussions, narratives and in-depth interviews with key informants, the study explored the clientelistic nature of the informal sector. The major findings of the study are that the informal sector in Zimbabwe is influenced by political patronage. It was established that patronage influences the informal sector in Zimbabwe in general and at Glen View Complex 8 in particular. Some of the operators revealed that patronage negatively affects their business as they are sometimes forced to attend political party meetings either at the complex or at ZANU-PF star rallies in town. The operators experience a plethora of problems such as lack of security, poor sanitation, stiff competition, poor infrastructure, lack of insurance and fire outbreaks. It has been revealed that most of the problems experienced at the complex are a result of the politicisation of the informal sector particularly by the ZANU-PF party. Operators at the complex have described the politicisation of the informal sector as a major drawback to their efforts of realising maximum benefits from their work. Therefore, the thrust of this thesis is premised on the de-politicisation of the informal sector as the starting point in the transformation of the activities of the operators. , Thesis (PhD) -- Faculty of Humanities, Sociology, 2021
  • Full Text:
  • Date Issued: 2021-04

Challenges and curriculum transformation in the higher education sector in South Africa: a case study in WASH to improve the training of pharmacists

  • Authors: Tandlich, Roman , Ngqwala, Nosiphiwe P , Boshoff, Aileen , Madikizela, Phindile , Srinivas, Sunitha C , Pyle, Desmond M , Oosthuizen, Rene
  • Date: 2018
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/76858 , vital:30631 , https://doi.org/10.2478/atd-2018-0001
  • Description: South Africa is a member state of the “BRICS” bloc (BRICS2017.org, 2017) and the G20 group of the 20 nations/economic blocs, which between them account for the majority of the world’s trade and economic activity. It faces many developmental challenges which are mirrored in its higher education sector. In this article, the authors seek to provide an overview of the challenges that South African higher education faces in the achievement of the developmental goals of the country. The focus of this paper is a case study in WASH (water, sanitation and hygiene) to improve context-specific responses that trains pharmacists on knowledge and skills.
  • Full Text:
  • Date Issued: 2018

A case study on the health risks related to flood disasters in South Africa

  • Authors: Tandlich, Roman , Ncube, Mbonisi , Khamanga, Sandile M , Zuma, Bongumusa M
  • Date: 2016
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/75917 , vital:30482 , DOI: 10.20965/jdr.2016.p0732
  • Description: Floods occurred in the Ndlambe Local Municipality in South Africa in October 2012. During various stages of the post-disaster recovery, bacterial concentrations were measured in water and soil samples from the flood zone. All drinking water concentrations of E. coli were below 1–3 colony forming units per 100 millilitres (CFUs/100 mL). The flood waters contained between 46500 to more than 100000 CFUs/100 mL of E. coli. {The concentrations of Salmonella spp. in the flood waters varied from 5000 to 250000 CFUs/100 mL. The presumptive Vibrio spp. concentrations in flood waters ranged from 1000 to over 150000 CFUs/100 mL. {The soil concentrations for E. coli ranged from 1 to above 330 colony-forming units per 1 g of soil dry weight (CFUs/g). The soil concentrations of Salmonella spp. varied from below 1 to 22 CFUs/g. The estimated airborne fungal concentrations ranged from 16820 to 28540 colony-forming units per 1 cubic meter. An outbreak of an infectious disease was recorded among the volunteers who assisted with the post-disaster recovery. The likely bacterial causative agents included strains of Aeromonas spp. and Vibrio cholerae. Any human contact with either the contaminated flood waters or of flooded dwellings should only occur, if the individuals in questions are equipped with the full-body personal protective gear. Non-governmental stakeholders performed majority of the post-disaster recovery operations, as the local government could only cover 11% of the required costs. Applying sanitation funds to disaster recovery and increased use of the low-cost flood defence products in high risk areas could provide a solution for the future.
  • Full Text: false
  • Date Issued: 2016

Biphenyl sorption to different soil clay minerals

  • Authors: Tandlich, Roman , Baláž, Štefan
  • Date: 2011
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/76869 , vital:30632 , https://doi.org/10.5897/AJAR10.1012
  • Description: Only limited information is available in the literature on the role of soil mineral surfaces in the sorption of hydrophobic organic pollutants. This knowledge gap is addressed through the assessment of biphenyl sorption to kaolinite, illite and bentonite; using the batch equilibration technique with incubations lasting 6 or 21 days at 28 ± 2°C in the dark [RT1]. Sorption of biphenyl onto kaolinite followed the Freundlich sorption isotherm, whereas linear sorption isotherms were observed on illite and bentonite [RT2]. The biphenyl sorption partition coefficient on kaolinite ranged from 0.1 to 9.1 cm3.g-1 after 6 days and no sorption was observed after 21 days. This could have been caused by a completely reversible sorption or a loss of binding capacity after 21 days [RT3]. The respective values of the biphenyl sorption partition coefficient on illite and bentonite ranged from 20.3 ± 0.3 to 120 ± 8 cm3.g-1.Sorption equilibrium on the internal clay surfaces was reached after 6 days, as indicated by the sorption data for illite and bentonite [RT4]. Access of biphenyl molecules to the internal clay surfaces is a function of the ionic strength of soil solution and the soil organic matter is the dominant site for biphenyl sorption after 6 to 21 days.
  • Full Text:
  • Date Issued: 2011
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