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The ecology and culture of the rock catlet Chiloglanis pretoriae (Pisces : mochokidae)

  • Authors: De Villiers, Pierre
  • Date: 1991
  • Subjects: Catfishes -- Africa , Catfishes -- Breeding -- Africa , Catfishes -- Ecology -- Africa , Fishes -- Cultural control -- Africa , Fishes -- Cultural control
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5267 , http://hdl.handle.net/10962/d1005111 , Catfishes -- Africa , Catfishes -- Breeding -- Africa , Catfishes -- Ecology -- Africa , Fishes -- Cultural control -- Africa , Fishes -- Cultural control
  • Description: Chiloglanis pretoriae is a rock catlet, indigenous to southern Africa. The aim of the study was to develop a technique to culture C. pretoriae as an alternative to harvesting and selling wild caught fish on the international aquarium trade. As nothing was known about the culture of African rock catlets an investigation into the biology and ecology of the species was necessary to develop the culture protocol. Chiloglanis pretoriae inhabits fast flowing rapids (current speeds over 0.6 metres per second). It is a serial interstitial gravel spawner, that spawns during the summer months. Chiloglanis pretoriae is a carnivorous fish species, feeding on aquatic insects. The natural growth rate is relatively fast in the first two years where after it levels off. Sexual maturity (50%) is attained within the first year (44mm total length). From the four cell stage, embryos took seven days to hatch, 16 days to first feeding and 75 days to reach the juvenile phase. The free embryos were well developed and readily accepted artificial feed at first feeding. The fish spawned readily, without hormone induction, in a continuous raceway. Spawning in the 801 retangular glass aquaria was irregular. The substrate within the raceway consisted of gravel and large rocks. The current was maintained at 0.6m/sec, temperature at 26± 0.6⁰C, dissolved oxygen concentrations at 7.1± 0.3mg/l, pH at 6.9± 0.2 and photoperiod at 16L:8D. Conductivity was monitored and remained within the acceptable range of C. pretoriae (84± 10uS/m).
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  • Date Issued: 1991

A qualitative investigation of schizophrenic dreams

  • Authors: Kumarapaapillai, Niranjula
  • Date: 1998
  • Subjects: Schizophrenia , Dreams -- Psychological aspects
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:3005 , http://hdl.handle.net/10962/d1002514 , Schizophrenia , Dreams -- Psychological aspects
  • Description: This project attempts to articulate an understanding of the worlds of selected subjects suffering from schizophrenia, through their dreams. It proceeds from the implicit question of whether or not schizophrenic dreams reflect the schizophrenic worlds as literature defines, and tries to address some of the dream features which reflect the schizophrenic world. Five psychiatric inpatients suffering from schizophrenia were selected. The data gathered included the subjects' dreams and subsequent interviews for the purpose of clarification of the dreams. A phenomenological-hermeneutic methodology was deemed to be appropriate as it gave access to the richness of the dream experiences as well as the following dialogue between the data and literature. The results indicate that the subjects' dream worlds bear evidence to a fragmented state of ego which is to be expected to be found in schizophrenia. On the other hand some of these subjects' dreams also point to evolving health that is present in their world, at least on an intrapsychic level.
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  • Date Issued: 1998

An evaluation of synergistic interactions between feruloyl esterases and xylanases during the hydrolysis of various pre-treated agricultural residues

  • Authors: Mkabayi, Lithalethu
  • Date: 2021-04
  • Subjects: Esterases , Xylanases , Hydrolysis , Agricultural wastes -- Recycling , Enzymes , Lignocellulose -- Biodegradation , Escherichia coli , Oligosaccharides , Hydroxycinnamic acids
  • Language: English
  • Type: thesis , text , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/178224 , vital:42922 , 10.21504/10962/178224
  • Description: Agricultural residues are readily available and inexpensive renewable resources that can be used as raw materials for the production of value-added chemicals. The application of enzymes to facilitate the degradation of agricultural residues has long been considered the most environmentally friendly strategy for converting this material into good quality value-added chemicals. However, agricultural residues are typically lignocellulosic in composition and recalcitrant to enzymatic hydrolysis. Due to this recalcitrant nature, the complete degradation of biomass residues requires the synergistic action of a broad range of enzymes. The development and optimisation of synergistic enzyme cocktails is an effective approach for achieving high hydrolysis efficiency of lignocellulosic biomass. The aim of the current study was to evaluate the synergistic interactions between two termite metagenome-derived feruloyl esterases (FAE6 and FAE5) and endo-xylanases for the production of hydroxycinnamic acids and xylo-oligosaccharides (XOS) from model substrates, and untreated and pre-treated agricultural residues. Firstly, the two fae genes were heterologously expressed in Escherichia coli, and the recombinant enzymes were purified to homogeneity. The biochemical properties of the purified recombinant FAEs and xylanases (XT6 and Xyn11) were then assessed to determine the factors which influenced their activities and to select suitable operating conditions for synergy studies. An optimal protein loading ratio of xylanases to FAEs required to maximise the release of both reducing sugar and ferulic acid (FA) was established using 0.5% (w/v) insoluble wheat arabinoxylan (a model substrate). The enzyme combination of 66% xylanase and 33% FAE (on a protein loading basis) produced the highest amounts of reducing sugars and FA. The enzyme combination of XT6 (GH10 xylanase) and FAE5 or FAE6 liberated the highest amount of FA while a combination of Xyn11 (GH11 xylanase) and FAE5 or FAE6 produced the highest reducing sugar content. The synergistic interactions which were established between the xylanases and FAEs were further investigated using agricultural residues (corn cobs, rice straw and sugarcane bagasse). The three substrates were subjected to hydrothermal and dilute acid pre-treatment prior to synergy studies. It is generally known that, during pre-treatment, many compounds can be produced which may influence enzymatic hydrolysis. The effects of these by-products were assessed and it was found that lignin and its degradation products were the most inhibitory to the FAEs. The optimised enzyme cocktail was then applied to 1% (w/v) of untreated and pre-treated substrates for the efficient production of XOS and hydroxycinnamic acids. A significant improvement in xylanase substrate degradation was observed, especially with the combination of 66% Xyn11 and 33% FAE6 which displayed an improvement in reducing sugars of approximately 1.9-fold and 3.4-fold for hydrothermal and acid pre-treated corn cobs (compared to when Xyn11 was used alone), respectively. The study demonstrated that pre-treatment substantially enhanced the enzymatic hydrolysis of corn cobs and rice straw. Analysis of the hydrolysate product profiles revealed that the optimised enzyme cocktail displayed great potential for releasing XOS with a low degree of polymerisation. In conclusion, this study provided significant insights into the mechanism of synergistic interactions between xylanases and metagenome-derived FAEs during the hydrolysis of various substrates. The study also demonstrated that optimised enzyme cocktails combined with low severity pre-treatment can facilitate the potential use of xylan-rich lignocellulosic biomass for the production of valuable products in the future. , Thesis (PhD) -- Faculty of Science, Biochemistry and Microbiology, 2021
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  • Date Issued: 2021-04

The naive moral as a possible mental attitude behind the outlaw-motif in English medieval narratives and its influence upon the structure of Thomas Lodge's "Rosalynde" and Shakespeare's "As you like it"

The constituents of the resin of Euryops floribundus. N.E.Br.

  • Authors: Woolard, Graham Robert
  • Date: 1966
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4510 , http://hdl.handle.net/10962/d1013449
  • Description: The aerial portions of the plant Euryops floribundus were extracted and shown to contain Euryopsonol and another sesquiterpenoid for which the name Euryopsol is proposed. An extraction of Euryops tenuissimus contained Euryopsol only. Euryopsonol, of empirical formula C₁₅ H₂₀ O₃, was previously shown to contain a hydroxyl group and a keto-group and to be doubly unsaturated. The hydroxyl group has been shown to be secondary, while the keto-group is ⋉, β, γ, δ-unsaturated, Spectroscopic and Mass spectrosmetric measurements showed euryopsonol to possess a furan ring and to be member of the eremophilane -9 of sesquiterpenoids . These proposals were confirmed by the conversion of euryopsonol to furanoeremophilone -9, thus establishing the stereochemistry at C₄, C₅ and C₁₀. This free hydroxyl group has been placed at C₃, but its stereochemistry is still unknown. Euryopsol, of empirical formula C₁₅ H₂₂ O₄, possesses an unstable furan ring and readily undergoes autoxidation, probably to a more stable ¥-lactone. It contains two vicinal hydroxyl groups, one of which was placed by Mass spectrometry at C₉. If euryopsol possesses the eremophilane skeleton the other hydroxyl group must be at C₁₀.
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  • Date Issued: 1966

Working inside Bank 4.0: analysing the impact of the 4IR on the organization of work in the banking sector of South Africa

  • Authors: Moshime, Kabelo Katlego
  • Date: 2021-10-29
  • Subjects: Industry 4.0 South Africa , Banks and banking South Africa , Banks and banking Technological innovations South Africa , Organizational change South Africa , Bank employees South Africa , Job security , Labour process theory
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10962/192386 , vital:45221
  • Description: The main objective of the study is to analyse the impact of the 4IR on the organization of work processes in the banking sector of Pretoria, South Africa. The Fourth Industrial Revolution (4IR) is an extension of the digital revolution based on the interconnectedness of machinery and cyber- physical systems that intelligently produce and control production. The South African banking sector has not been immune to the changes brought on by the 4IR in other sectors, as many financial institutions in the country have digitized the bulk of their services, in order to make banking quicker and more efficient. Additionally, the latest COVID-19 pandemic has accelerated the emergence of digital solutions and e-commerce across different sectors worldwide, thus showing that 4IR is here to stay. On the surface, the adoption of various technological innovations within the banking sector seems like a logical step towards building a more efficient banking system, with minimal deficiencies and upskilling opportunities for banking employees, thus providing an improved and convenient banking experience for customers. On the other side, however, one can see general trends that may not be in the best interest for people employed within the banking sector. For example: the introduction of new technologies has reduced the number of employees in banks; the skills upgrade that some bankers have experienced as a result of new technologies, have come at the cost of the many job losses in the sector; also, the control methods in the banks have become more centralised, thus ensuring extreme monitoring of staff. Additionally, new technologies have eliminated the spaces for deficiencies, and have given consumers a greater role in their banking experiences, instead of being assisted from a-z in their local branches. In light of these changes, one has to question the real impact of these changes on the people that have chosen banking as a career, as ‘machines’ have taken over their banking institutions. Using the Labour Process Theory (LPT), this study examined the impact of the 4IR processes on the organization of work and the general employment experiences of employees in the banking sector of Tshwane, in the Gauteng province, of South Africa. This study found the following outcomes: technologies facilitate greater monitoring of the workplace, enable flexible specialisation for workers, reduces foot-flow in bank branches, and shifts the bankers’ work into the hands of the customers. , Thesis (MSocSci) -- Faculty of Humanities, Sociology, 2021
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  • Date Issued: 2021-10-29

Energetic and kinematic responses to morphology-normalised speeds of walking and running

  • Authors: Williams, Martin Andrew
  • Date: 1989
  • Subjects: Running -- Physiological aspects , Walking -- Physiological aspects
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5166 , http://hdl.handle.net/10962/d1016240
  • Description: This study investigated the influence of human morphology upon selected physiological, biomechanical and psychological responses to horizontal locomotion. In so doing, it was possible to evaluate the effectiveness with which morphology-normalised speeds of walking and running reduced the between-subject variability that is inherent in human locomotor responses. Twenty caucasian males were divided into two groups on the basis of stature - ten subjects in each of a "short" category (<170cm) and a "tall" category (>185cm). All subjects were habituated to treadmill locomotion prior to exposure to three walking treatments (0.83, 1.39 and 1.94m.s⁻¹) and three running treatments (2.50, 3.06 and 3.61m.s⁻¹). During each of these five-minute locomotor conditions, energetic (V02), kinematic (cadence and stride length) and psychophysical (central and local RPE) data were captured. From these data, lines of best fit were calculated for each subject, allowing for a prediction of the abovementioned locomotor variables from known absolute rates of progression. Using suitable regression equations, subject responses to morphology-normalised speeds of walking and running were effectively extrapolated. When the rate of progression was expressed in absolute terms (m.s⁻¹), significant differences (P <0.05) were found between the stature-related groups with respect to both energetic and kinematic locomotor responses. Such differences were successfully eliminated when use was made of locomotor speeds relativised on the basis of morphology. This study concludes that the use of appropriately prescribed morphology-normalised rates of progression are effective in reducing the variability in locomotor responses between subjects differing significantly in stature.
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  • Date Issued: 1989

Exploring the need for Academic Support Programmes (ASPs) for returning undergraduates at Rhodes University

  • Authors: Matabane, Ramathetse Belinda
  • Date: 2017
  • Subjects: Compensatory education -- South Africa -- Makhanda , Rhodes University. Department of Sociology
  • Language: English
  • Type: Thesis , Masters , MSocSc
  • Identifier: http://hdl.handle.net/10962/35094 , vital:24326
  • Description: The overarching purpose of this thesis is to explore the need for Academic Support Programmes (ASPs) in higher education with specific reference to returning undergraduates in the Sociology Department at Rhodes University. The transformational agenda in higher education in post-apartheid South Africa in terms of expanding access to education, the promotion of accountability and efficiency in higher education, massification, the articulation gap between school and university, institutional culture, unpreparedness of universities and underpreparedness of students comprise the conceptual core of this study. I undertake to investigate the necessity and relevance of academic support offered to returning undergraduates at Rhodes University. I do this by exploring two main issues theoretically and in my fieldwork. The two main issues that form the basis of this research are students’ perceptions regarding availability and accessibility of academic support programmes in the Sociology Department and students’ perceived academic needs. Students’ perceptions and attitudes towards Academic Support Programmes have been uncovered through both quantitative and qualitative fieldwork to gauge the extent to which literature is applicable when it comes to the above-mentioned conceptual frameworks. The study illustrated that academic support is not exclusive to first year students. It is also clear that improved, systematic academic support gives rise to improved student academic performance. Throughout the study, students perceive availability and accessibility of ASPs as a challenge.
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  • Date Issued: 2017

Gold fineness in hydrothermal ores : an investigation into the distribution of gold and silver in Southern Rhodesian gold ores

  • Authors: Eales, Hugh V
  • Date: 1961
  • Subjects: Hydrothermal deposits -- Zimbabwe , Gold ores -- Zimbabwe , Silver ores -- Zimbabwe , Silver mines and mining -- Zimbabwe
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:5077 , http://hdl.handle.net/10962/d1014887
  • Description: This investigation is concerned with primary variations in the silver content of gold which occurs in hydrothermal deposits, particularly those of hypothermal character which are found in Basement rocks in Southern Rhodesia. The nature of the gold produced by a number of different mines has been studied by reference to production data, and microscope techniques as well as gold and silver assays have been used to determine and to explain the variations in gold fineness. The literature does not contain a great deal of information which is relevant to this topic, but an attempt has been made here to summarize the more important contributions by different writers. From this it emerges that the interpretations given by different investigators are in conflict and that paradoxes may arise when efforts are made to explain observed variations in fineness in terms of certain generalizations which have become entrenched in the literaure. In particular, it is shown that falling temperature alone cannot account for the occurrence of silver-rich gold in certain deposits. The Gwanda district of Southern Rhodesia has been selected as a typical gold belt, and the variation in fineness in 150 producers is described. The deposits are hypothermal in character, and the average fineness of the gold is high but variable, but in a small proportion the fineness is low. It is shown that the nature of the host rock and the distance of a deposit from the granite contact appear to have no influence on the fineness of the gold and that there is no zonal arrangement of fineness values. There is a suggestion that diversity of mineral species in any particular area may be accompanied by rather wide fluctuations in the gold fineness. The variations of fineness in eight typical Southern Rhodesian deposits are studied in detail, by analysis of production data, by assaying specimens of the ore and by the examination of polished specimens of gold-bearing ore. Briefer reference is made to two other deposits in the territory, and to deposits in other countries which appear to bear out the conclusions reached in this section. It emerges that there are two factors which can commonly be correlated with variations in fineness. The first of these is the grade of the ore: high-grade ore generally contains purer gold than low-grade ore. Secondly, the textural evidence indicates that gold which separates relatively early in the paragenesis contains more silver than that which is deposited in the final stages of metallization. A general survey which draws on the literature as well as on the writer's examinations of deposits in the territory indicates that, in general, gold which is associated with late-stage minerals such as tellurides, antimony, bismuth and bismuthinite is silver-poor. Gold associated with galena may be either silver-rich or silver-poor, whereas gold which is of the same age as chalcopyrite or sphalerite is very frequently rich in silver. The difficulty which is encountered in establishing the age of gold which is intimately associated with pyrite and arsenopyrite renders uncertain the correlation between fineness and age of gold in these latter cases. There are, however, indications that gold which is truly contemporaneous with either pyrite or arsenopyrite is silver-rich. In the discussion, the objections to the common practice of singling out temperature as the most potent factor controlling gold fineness are listed. Chief amongst these objections is the fact that gold does not in all deposits increase in fineness with increasing depth: examples are quoted where fineness was found to decrease as deeper levels of the ore body were exploited. It is shown that there is no consistent relationship between the size of gold grains and their silver content. It is the writer's conclusion that in hydrothermal deposits in this territory the high fineness of the gold is due to increasing solubility of silver in the ore fluids in the late states, and that where hydrothermal deposits are characterized by gold with low average fineness, an unusually large proportion of the gold has been deposited early in the paragenotic sequence. In the majority of hypothermal deposits, however, the bulk of tho gold separates late in the sequence and the fineness is accordingly high. It is believed that the relationship which exists between fineness and tenor in many deposits is due to protracted crystallization of gold in those portions of the ore body which remained permeable to the latest stages. These portions of the ore body, which represent either valuable ore shoots or ore shoots in miniature, are likely to contain gold of variable character, but the average silver content will be low because a large proportion of the gold is "late" gold. The factors which might cause epithermal gold to have a lower fineness than mesothermal or hypothermal gold are briefly discussed. Some possible applications of this study are indicated in the final chapter. It is claimed that records of gold fineness might constitute a valuable addition to mill records. Tentative suggestions are made regarding a method whereby the approaching exhaustion of a deposit might in some cases be predicted. With regard to the origin of the gold in the Witwatersrand sediments, it is pointed out that the modified placer hypothesis is not fully equipped to explain certain of the variations in the composition of the gold.
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  • Date Issued: 1961

Binding and transcriptional activation by Uga3p, a zinc binuclear cluster protein of Saccharomyces cerevisiae redefining the UAS [subscript GABA] and the Uga3p binding site

  • Authors: Idicula, Anu Mary
  • Date: 2003
  • Subjects: Saccharomyces cerevisiae GABA
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:3933 , http://hdl.handle.net/10962/d1003992
  • Description: Uga3p, a member of the zinc binuclear cluster transcription factor family, is required for [gamma]-aminobutyric acid-dependent transcription of the UGA genes in Saccharomyces cerevisiae. Crystallographic data of some of the protein-DNA complexes of this family reveal that members of this family bind to CGG triplets. A conserved 19-nucleotide activation element in certain UGA gene promoter regions contains a CCG-N4-CGG everted repeat, proposed to be the binding site of Uga3p, UAS[subscript GABA]. The spacer region (N4) between the CGG triplets has been suggested to be the specificity determinant for binding to UAS[subscript GABA]. The data available from the Saccharomyces genome database indicates that there are multiple repeats of -CCG-N4-CGG- regions within the genome. These transcription factors are involved in the activation of specific pathways and the question arises as to how their specificity of binding is determined. The aim of this study was to understand the binding characteristics of Uga3p to UAS[subscript GABA] and to determine the affinity and specificity of this interaction. In this study, full-length (tagged and untagged) and truncated (1-124 a.a.) Uga3p was produced in a heterologous expression system (E. coli). The interaction of Uga3p with UAS[subscript GABA] in Saccharomyces cerevisiae was characterized in terms of binding in vitro and the transcriptional activation of lacZ reporter genes in vivo. The Uga3p was capable of binding to these sites in vitro independent of exogenous GABA. Electrophoretic mobility shift assays (EMSA) of the full-length Uga3p with the wild type UAS[subscript GABA] sequences produced two distinct mobility complexes. The complexes formed in the EMSA of the full-length Uga3p were those specific to the interaction of the Uga3p to UAS[subscript GABA]. The truncated Uga3p(1-124 a.a.), which has the DNA-binding zinc cluster domain, the linker region and the putative coiled-coil domain was not functionally equivalent to the full-length protein with respect to binding in vitro because the EMSAs of the UAS[subscript GABA] with the truncated Uga3p produced indistinct complexes. EMSAs using mutant UAS[subscript GABA] sequences and heterologously-produced full-length Uga3p, demonstrated that UAS[subscript GABA] consists of two, independent Uga3p-binding sites. This work presents evidence that the two Uga3p molecules bound to UAS[subscript GABA] most likely interact with each other. Unlike other zinc cluster binding sites the Uga3p-binding site is an asymmetric site of 5’-SGCGGNWWT-3’ (S= G or C, W = A or T and N = no nucleotide or G or C). UAS[subscript GABA] is a palindrome containing the two asymmetric Uga3p-binding sites. The two-site consensus sequence required for the binding of Uga3p to the UAS[subscript GABA] is present upstream of UGA1 (region -387 to -370) and UGA4 (region -403 to -387). Furthermore, a single Uga3p-binding site was identified in the 5’ untranslated regions of UGA2 (region -219 to -211). GABA-dependent transcriptional activation by UAS[subscript GABA] in vivo could be directly correlated to a high affinity, specific interaction of two Uga3p molecules to this UAS. Binding with high affinity required the conserved sequences flanking the everted repeat. This study provided evidence that the binding pattern of Uga3p is novel compared to other zinc cluster motifs investigated, as the sequences flanking the everted repeat are important regions for recognition by Uga3p. The studies with the truncated Uga3p (1 –124 a.a.), also suggested that the regions C-terminal to the DNA-binding motif and putative coiled-coil area of this protein are important for Uga3p-specific interactions with UAS[subscript GABA]. Investigation of regions C-terminal to the zinc cluster, linker and putative coiledcoil revealed an eight-motif regulatory region similar to that in other zinc cluster proteins. This indicated that the regions C-terminal to these domains are important for the regulation and activity of these proteins. A putative seven repeat WD40-like motif was identified within this region. This putative domain has been speculated to be important for protein-protein interactions. Phosphorylation and dephosphorylation in other proteins of this class have been indicated to be important for the regulation of the activity of these proteins. The bioinformatic analysis of Uga3p revealed two possible cAMP/cGMP-dependent protein kinase phosphorylation sites, four putative protein kinase C phosphorylation motifs and four putative casein kinase II phosphorylation motifs. This study has contributed to the understanding of the nature of interactions between Uga3p and its specific UAS [subscript GABA] and how the regions flanking the everted repeat determine its specificity. The comparison of the nature of the binding of truncated and full-length Uga3p in vitro provided evidence for the role played by the full-length protein in determining this specific interaction. This evidence suggested that the in vitro binding evidence for other proteins of this family, using truncated peptides that carry the DNA-binding domain, might not reflect the true nature of interactions between the proteins of this class and their specific UASs in vivo.
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  • Date Issued: 2003

Address of welcome by VC at the 1985 Annual Conference of Teachers of African Government and Development Administration

  • Authors: Henderson, Derek Scott
  • Date: 1985-09-13
  • Language: English
  • Type: Text
  • Identifier: vital:7501 , http://hdl.handle.net/10962/d1018378
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  • Date Issued: 1985-09-13

Understanding how trainee teachers engage with prior everyday knowledge and experience associated with biological concepts during integrated natural science education 5-7 : a case study

  • Authors: Enghono, Albertina Magano
  • Date: 2014
  • Subjects: Biology teachers -- Training of -- Namibia -- Case studies Teacher educators -- Training of -- Case studies Teachers -- Training of -- Namibia -- Case studies Education -- Namibia -- Case studies Prior learning -- Namibia
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1970 , http://hdl.handle.net/10962/d1011972
  • Description: Since the Namibian independence in 1990, the education system has undergone some major revamping which involved the adoption of social constructivist perspectives in the teaching and learning of sciences. This learning theory acknowledges learners’ background prior knowledge as valuable tools in the effective construction of science concepts during lessons. A corollary is that the socio-cultural circumstances of learners might negatively influence the way learners construct new knowledge in the science classroom if they are not taken into consideration. This study was thus prompted by the need to understand how trainee science teachers engage with prior everyday knowledge and experiences, so as to enhance the conceptual development of biological concepts. The study was qualitative and it was underpinned by an interpretive paradigm with some elements of action research. Science trainee teachers at Katima Mulilo, Unam Campus were used as research participants. The techniques used to gather data included document analysis, brainstorming, observation, audio-visual, microteaching and semi-structured interviews. The results of this study showed that the changes that occurred during microteaching practices of the four trainee teachers involved in the study reflected their professional development in this approach. However, it emerged that prior everyday knowledge can be both a barrier and enabler to the construction of meaningful teaching and learning; hence its oversight may lead to instructional failures. The findings also indicated that selected platforms are essential to enable trainee teachers to incorporate prior everyday knowledge and experiences into the teaching of Western science. However, larger scale study should be conducted in order to deepen the understanding of the topic.
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  • Date Issued: 2014

The rising popularity of Pidgin English radio stations in Nigeria: an audience study of Wazobia FM, Lagos

  • Authors: Durodola, Olufunke Treasure Anike
  • Date: 2014
  • Subjects: Wazobia FM (Nigeria) , Radio audiences -- Nigeria -- Lagos , Pidgin English -- Nigeria -- Lagos , Radio stations -- Nigeria -- Lagos , Mass media and culture -- Nigeria -- Lagos , Language and languages -- Variation , Popular culture -- Nigeria , Postcolonialism -- Nigeria
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:3550 , http://hdl.handle.net/10962/d1020886
  • Description: This research is located within media studies and draws on the Cultural Studies approach. It is an audience study, which uses the mixed methods of focus group discussions and an online survey to examine the importance of the use of Nigerian Pidgin as a broadcast language in investigating the rising popularity of Pidgin English radio in a multi-ethnic and multi-lingual Nigeria. The study focuses on Wazobia FM, a radio station in Lagos, and the first pidgin station in Nigeria. It seeks to determine whether the station’s audience engaged with the station’s programming based on its prioritisation of NigP and the linguistic identity it offers them. The study foregrounds the marginalised status of NigP within the politics of language in Nigeria. It traces the language’s evolution through popular and oppositional expressions in broadcasting and in music. It also seeks to establish the place of Pidgin English within the role that language plays in the formation of the Nigerian identity. This study thus adopts the ‘emic’ perspective, which underpins qualitative methodology, and views social life in terms of processes as opposed to static terms. The theoretical framework of this research revolves around culture, language and identity. Pertinent concepts in post-colonial studies, together with conceptual frameworks in Cultural Studies, such as popular culture, representation, hegemony and counter-culture have been used to make sense of the popularity of NigP radio stations.
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  • Date Issued: 2014

Enabling social learning as a response to environmental issues through teaching of localised curriculum in Zambian schools

  • Authors: Sinyama, Imakando
  • Date: 2012
  • Subjects: Social learning -- Zambia -- Keembe (Central Province) Environmental education -- Zambia -- Keembe (Central Province) Environmental education -- Study and teaching -- Zambia -- Keembe (Central Province) Sustainable development -- Study and teaching -- Zambia -- Keembe (Central Province) Curriculum change -- Zambia -- Keembe (Central Province) Educational evaluation -- Zambia -- Keembe (Central Province)
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1508 , http://hdl.handle.net/10962/d1003390
  • Description: Schools are traditionally established as the main meeting platforms for awareness, education, training and capacity building in the local communities, and as such, are highly regarded and respected. They are situated and integrated in nearly all local communities. They are thus perfectly suited to reach, draw on and provide capacity building to the communities. Zambia recently introduced a new curriculum aspect named localised curriculum, which makes up 20% of the curriculum. This curriculum area encourages schools to address issues of sustainable development that are locally relevant through this curriculum component, but it is not clear what kind of learning emerges from this curriculum aspect. The study looked at the shift in pedagogical discourse since the introduction of the localised curriculum. Using case study methodology and observation of a number of classroom activities in the Keemba District near Monze in Zambia, I observed social learning interactions taking place in the implementation of the localised curriculum. In particular, I was interested in how the different aspects of the localised curriculum enabled social learning, at different levels. What is important in this research is that it focused not so much on what people should know, or be able to do, but rather, drawing on some of the questions raised by Wals (2007), I considered questions of how people learn, and how social learning emerges in school-community interactions in the localised curriculum. The main research question was to investigate: How does localised curriculum enable social learning in response to environmental issues in Zambian schools? This research drew on a number of associated research projects that were carried out in southern Africa and beyond. In his research, Namafe (2008) states that he saw a great need to institutionalise increased participation of Zambian Basic Schools and their local communities in sustainable development of the country in order to alleviate poverty and achieve equitable development. Hogan (2008, p. 122 ) researching in a different context, argues that contextualisation of the curriculum allowed for indigenous knowledge to come in to the classroom, stating that ‘Weakening of the frames provided the opportunity of closer relationships to give space for knowledge other than teacher selected knowledge or book knowledge to enter the classroom.’ In this study I found that: - Teaching localised curriculum allowed for contextualisation and integration of environment and natural resource management issues - Localising the curriculum contributed to curriculum relevancy: teaching localised curriculum helped learners, teachers and community to develop concern for quality of life and contributed to an understanding of sustainable development - Localised curriculum allowed for frame awareness, frame deconstruction and reframing to take place: this allowed teachers to use methods which promoted active pupil participation and interaction, encouraging learners to be reflexive thinkers rather than just using rote memory - Participation of teachers, community and learners in the implementation of the localised curriculum: The involvement of community members to teach topics of the localised curriculum was useful and articulated processes of inter–epistemological dialogue between traditional or every day and scientific or institutional knowledge - The localised curriculum implementation involved various roles and was influenced by various factors. Of key interest to this study was the fact that neither parents, learners nor teachers saw the localised curriculum as an opportunity for problem solving, but rather emphasised the learning of practical life skills relevant to the community. This differed from the curriculum manuals, and reduced the environmental education potential and also social learning opportunities.
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  • Date Issued: 2012

Applications of camphor-derived chiral auxiliaries in the asymmetric synthesis of α-amino acids and other systems

  • Authors: Matjila, Joseph Moemise
  • Date: 1998-04
  • Subjects: Uncatalogued
  • Language: English
  • Type: Doctoral theses , text
  • Identifier: http://hdl.handle.net/10962/191501 , vital:45106
  • Description: A viable synthetic route to camphor-derived imino lactones as precursors for the asymmetric synthesis of a-amino acids has been established. Several synthetic strategies have been investigated and the required regioisomeric imino lactones were finally obtained via the step-wise condensation of JV-(carbobenzyloxy)glycine with the a-ketols, 3-exo-hydroxycamphor and 2-exo- hydroxy-3-bomanone. Enolates of the camphor imino lactones, generated using potassium tert- butoxide, were reacted with a range of alkyl halides. Dialkylation was observed using the 2-imino lactone, while the regioisomeric 3-imino lactone derivative gave monoalkylated products with diastereoselectivities, shown by NMR spectroscopy, to range from 43% d.e. for the methylated product to > 99% d.e. for larger alkyl groups. The expected preference for endo-alkylation is supported by NMR (chemical shift, coupling constant and NOE) data and was confirmed by acidic hydrolysis of the pentylated 3-imino lactone to afford the known acid. Computer modelling, with the software package HYPERCHEM®, was used to explore the conformational properties of the alkylated products and their enolate precursors. Exploratory work on the enantiomeric beneficiation of racemic amino acids, using alkylated imino lactone derivatives, revealed preferential exo-protonation of the enolate intermediates. Asymmetric Baylis-Hillman reactions between a novel camphor-derived acrylic ester and a range of aldehydes afforded the corresponding 2-(hydroxyalkyl)acrylates in up to 59% d.e., the observed stereoselectivities being sensitive to both steric and electronic factors. Attempts to prepare imino lactone derivatives from ketopinic acid, although unsuccessful, led to the isolation of two novel W-(carbobenzyloxy)glycinates, whose structures were established by 1- and 2-D NMR spectroscopy. Attempts to prepare "BINAP" analogues from dibomyl ether's also proved unsuccessful, but the investigation led to the discovery of a third, novel dibomyl ether. , Thesis (PhD) -- Faculty of Science, Chemistry, 1998
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  • Date Issued: 1998-04

Launch of the Rhini/Grahamstown Schools Partnership

  • Authors: Badat, Saleem
  • Date: 2014-12-04
  • Language: English
  • Type: Text
  • Identifier: vital:7723 , http://hdl.handle.net/10962/d1015870
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Characterisation of Human Hsj1a : an HSP40 molecular chaperone similar to Malarial Pfj4

  • Authors: McNamara, Caryn
  • Date: 2007
  • Subjects: Heat shock proteins , Protein folding , Proteins -- Analysis , Proteins -- Structure , Plasmodium , Malaria , Molecular chaperones
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4083 , http://hdl.handle.net/10962/d1007603
  • Description: Protein folding, translocation, oligomeric rearrangement and degradation are vital functions to obtain correctly folded proteins in any cell. The constitutive or stress-induced members of each of the heat shock protein (Hsp) families, namely Hsp70 and Hsp40, make up the Hsp70/Hsp40 chaperone system. The Hsp40 J-domain is important for the Hsp70-Hsp40 interaction and hence function. The type-II Hsp40 proteins, Homo sapiens DnaJ 1a (Hsj1a) and Plasmodium falciparum DnaJ 4 (Pfj4), are structurally similar suggesting possible similar roles during malarial infection. This thesis has focussed on identifying whether Hsj1a and Pfj4 are functionally similar in their interaction with potential partner Hsp70 chaperones. Analysis in silico also showed Pfj4 to have a potential chaperone domain, a region resembling a ubiquitin-interacting motif (UIM) corresponding to UIM1 of HsjIa, and another highly conserved region was noted between residues 232-241. The highly conserved regions within the Hsp40 J-domains, and those amino acids therein, are suggested to be responsible for mediating this Hsp70-Hsp40 partner interaction. The thermosensitive dnaJ cbpA Escherichia coli OD259 mutant strain producing type-I Agrobacterium tumefaciens DnaJ (AgtDnaJ) was used as a model heterologous expression system in this study. AgtDnaJ was able to replace the lack of two E coli Hsp40s in vivo, DnaJ and CbpA, whereas AgtDnaJ(H33Q) was unable to. AgtDnaJ-based chimeras containing the swapped J-domains of similar type-II Hsp40 proteins, namely Hsj1Agt and Pfj4Agt, were also able to replace these in E. coli OD259. Conserved J-domain amino acids were identified and were substituted in these chimeras. Of these mutant proteins, Hsj IAgt(L8A), Hsj1Agt(R24A), Hsj1Agt(H31Q), Pfj4Agt(L 11A) and Pfj4Agt(H34Q) were not able to replace the E. coli Hsp40s, whilst Pfj4Agt(Y8A) and Pfj4Agt(R27A) were only able to partially replace them. This shows the leucine of helix I and the histidine of the loop region are key in the in vivo function of both proteins and that the arginine of helix II is key for Hsj1a. The histidine-tagged Hsj1a protein was also successfully purified from the heterologous system. The in vitro stimulated ATPase activity of human Hsp70 by Hsj1a was found to be approximately 14 nmol Pí[subscript]/min/mg, and yet not stimulated by Pfj4, suggesting a possible species-specific interaction is occurring.
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  • Date Issued: 2007

Conceptualising community radio: from global histories to the Kenyan example

  • Authors: Korir, Geoffrey Kiplimo
  • Date: 2020
  • Subjects: Community radio , Community radio -- Kenya , Community development -- Kenya , Social change -- Kenya , Radio broadcasting -- Kenya
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/165766 , vital:41279
  • Description: This study sets out to gain insight into the way that the establishment of community radio in Kenya is located within the global history of ideas about such radio. The first four chapters in this study provide terms of reference for this examination through a series of literature reviews. It sets out, firstly, to locate the internationally shared conceptualisaiton of community radio within an existing spectrum of approaches to social analysis. It proposes that community radio can be located at the critical, emancipatory end of this spectrum. It then maps out the global circulation of ideas about community radio and proposes that such circulation was informed by the broader history of critical, emancipatory social analysis. The final literature review then deals with community radio in Kenya and examines the way in which the establishment of this sector was shaped by the social and political history of this country. It is argued that the establishment of a community radio sector became possible only when support for emancipatory approaches to media became acceptable in Kenya, in context of the establishment of multiparty democracy. It is proposed, further, that the articulation of a vision for community radio in Kenya depended in part on the existence of international support for such radio and in part on the efforts of local actors in civil society. The empirical component then focuses on the way global ideas about community radio have become realised in Kenya. The study achieves this purpose by drawing on qualitative interviews with individuals from within civil society who have participated in the history of the establishment and growth of community radio in Kenya. These individuals demonstrate consciousness of the internationally shared set of principles that can facilitate a successful establishment of community radio. However, they are also sceptical of the assumption that guidelines for community radio are universally applicable. They point, in particular, to the challenges involved in the realisation of these guidelines in an environment in which economic resources are limited, and which is characterised by extreme social inequality and conflict. The study concludes that it is individuals such as these participants, who are embedded within the local context, who are best placed to articulate locally appropriate alternatives to these guidelines.
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  • Date Issued: 2020

A mineralogical study of phosphate mineralisation in the Nkombwa Hill Carbonatite

  • Authors: Mapholi, Thendo
  • Date: 2021-10-29
  • Subjects: To be added
  • Language: English
  • Type: thesis , text , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/294797 , vital:57256
  • Description: Thesis embargoed. Release date October 2023. , Thesis (MSc) -- Faculty of Science, Geology, 2021
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  • Date Issued: 2021-10-29

The notion of physicality in vocal training for the performer in South African theatre, with particular reference to the Alexander technique

  • Authors: Cox, Frances Jayne
  • Date: 1991
  • Subjects: Voice culture , Alexander technique , Drama -- Study and teaching
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2134 , http://hdl.handle.net/10962/d1002366 , Voice culture , Alexander technique , Drama -- Study and teaching
  • Description: Voice training has been influenced by separatist attitudes which have allowed for classes which train the body to be separate from those which train the voice. This study acknowledges that to train an actor in separate compartments and then expect the completeness of human expression in performance, is to train under false pretences. There is a need to address the imbalance of separatism and this is examined within the context of voice training. An holistic approach to voice training forms the basis of the argument, which focuses on the need to re-educate the notion of physicality in voice training. Chapter one proposes an understanding of the notion of physicality by drawing on the attitudes of selected theatre practitioners towards the physical nature of the theatre encounter. The expressive energies of the actor's body are responsible for the physicalisation of a play; for this reason the movement of voice and speech is not only examined as source movement, but also as the movement of an actor's response and communication. Chapter two examines some practices which led to attitudes of separatism in voice training, and introduces prevalent practices which are attempting to involve the energy of the physical experience. Chapter three proposes that the Alexander technique be used as the foundation for an awareness of individual physicality. Where chapter one examines the theory of this notion, chapter three proposes an experiential understanding of the same. The Alexander technique is a training in effective body use and it's principles are fundamental to an awareness of body use and functioning. It is argued that these principles should underlie a re-education of physicality. The final chapter of the thesis argues for physicality in South African voice training programmes which would complement the physicality of contemporary theatre forms. It is hoped that this study will provide further incentive for the continued review and adjustment of drama training in South Africa.
  • Full Text:
  • Date Issued: 1991
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