List of Titles

Exploring integration for the topic of stoichiometry in South African natural sciences and physical sciences school curricula

- Mgolozeli, Kwanele

Authors: Mgolozeli, Kwanele
Date: 2022-10-14
Subjects: Uncatalogued
Language: English
Type: Academic theses , Master's theses , text
Identifier: http://hdl.handle.net/10962/405330 , vital:70162
Description: Many developing countries, including South Africa, have identified the provision and implementation of strong science curricula as central to their developmental needs. Stoichiometry is a fundamental chemistry topic because the concepts involved form the basis of later topics such as chemical equilibrium, rates of reactions, redox reactions, and acid-base reactions. School students consistently demonstrate lack of understanding of stoichiometry-related concepts and skills such as the particulate nature of matter and related mathematical problem-solving. The poor performance of high school students in central science topics such as stoichiometry is problematic for their further study of chemistry and for the country meeting its need for science graduates. Successive examiner reports pointed to the lack of integration of stoichiometry concepts across the grades being the main problem. However, no study could be found which explores how stoichiometry is integrated in the South African Natural Sciences and Physical Sciences curriculum across the grades. This provided the rationale for the current study. The case study reported in this thesis thus aimed to explore integration of stoichiometry concepts in South African Natural Sciences and Physical Sciences school curricula. It involved document analysis as the method of collecting data. The research adopted the social realist paradigm, with its realist ontology and relativist epistemology. Legitimation Code Theory provided the theoretical framing. Chemistry concepts that are foundational to the understanding of stoichiometry according to literature, were chosen as root concepts for the concept mapping undertaken to identify types of integration. The concept maps revealed four stoichiometry integration themes: integration of stoichiometry concepts with symbols, integration of stoichiometry concepts with explanations, integration with applications in a chemistry context, and integration with an everyday context. These themes provided integration categories. A semantic gravity translation device was then developed for characterising the types of integration in terms of the degree of contextualisation. The results of this study show that stoichiometry integration of weaker semantic gravity is legitimated more strongly over other semantic gravity codes in the Natural Sciences and Physical Sciences curricula across all grade levels. While this has advantages in terms of knowledge-building potential, the consequence is that the integration occurs at very abstract levels that are far removed from learners’ everyday lives. The practical implication for curriculum developers involves increasing the instances of integration of stoichiometry concepts at stronger levels of semantic gravity, for a more even semantic gravity range of integration types. Natural Sciences and Physical Sciences teachers also need to source and include real-life examples for explanations and applications of stoichiometry concepts when teaching, in light of current curriculum documents focusing more on abstract forms of integration. Methodologically, this study contributes to the increased utility of semantic gravity through its exploration of integration in relation to knowledge-building potential of curriculum for hierarchical knowledge structures such as chemistry. , Thesis (MEd) -- Faculty of Education, Education, 2022
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Date Issued: 2022-10-14

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Composition portfolio

- Moss, Keith

Authors: Moss, Keith
Date: 2007
Subjects: Uncatalogued
Language: English
Type: Master's theses , text
Identifier: http://hdl.handle.net/10962/193724 , vital:45390
Description: Whitacre's music is primarily diatonic with subtle modulations, where the new key is always preserved diatonicaliy as well. I refer to this style as expanded diatonicism. Examples in my work of expanded diatonicism within this portfolio are to be found in navem ad somnium, Wynken, Blynken and Nod, as well as Hymn for Brass. My applications of expanded diatonic practices within each of these works are discussed in a separate appendix within the body of this portfolio. That these works are vocal or have a vocal inspiration (Hymn for Brass) reveals the extent of my initial reaction to Whitacre's music during a choral rehearsal. Furthermore, in my vocal compositions especially I chose texts which frequently gravitate towards ideas related to water, the ocean and ships. Whilst water has a soothing and inspiring influence upon me, presumably evidenced in my expanded diatonicism, it also represents my journey and investigation into the sound work of Whitacre in particular. It may be noticed that many of my works in this portfolio have religious orientated themes. I am a Christian, and belong to a Berean 2 Congregational Church. Whilst I am not Catholic or Anglican, I nonetheless have made use of texts from the liturgy of these denominations, as they emphasise the basis of my Christian faith. Why I chose Hymn for Brass as a title could possibly be construed as a religious reference, however it was named after the piece was written, and had no theological connotations in its inception save for the hymnody style of the orchestration. Providence and The Eventide both have a Christian philosophical foundation which is explored in depth in the accompanying appendix. The latter work explores an extension of my expanded diatonic style through incorporating aspects of chromaticism. The rationale for this is dealt with in my discussion of this work. This portfolio represents an overview of my compositional activities to date and displays my growing confidence with the technical aspects of composition as well as my yearning for experimentation with new ideas and manners of expression. , Thesis (MMus) -- Faculty of Humanities, Music and Musicology, 2007
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Date Issued: 2007

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A comparison of the self-esteem of black and white high school pupils

- Morrow, Brian Robert

Authors: Morrow, Brian Robert
Date: 1988
Subjects: Uncatalogued
Language: English
Type: Master's theses , text
Identifier: http://hdl.handle.net/10962/193033 , vital:45292
Description: This study investigated the level of self-esteem of black and white high-school students using the Rosenberg self-esteem scale. One hundred and eighty six subjects were used, 63 of them being white while 118 were black. A validation of the Rosenberg scale for the black sample was attempted using a correlation between the scale score and a rating of the subjects by teachers. The results of the study showed no significant difference between the self-esteem levels, while the validation study failed to confirm the validity of the test for black subjects in South Africa. However, the validation study v/as rejected as inconclusive and the results of the comparison accepted as confirmatory of previous research. An incidental positive finding revealed that white males have higher self-esteem than white females,. The theory and past research of self-esteem comparisons between racial groups is reviewed. The conclusion is reached in this study that the concept of self-esteem has outlasted its usefulness in the field of comparisons between racial groups and research of a qualitative nature .can provide further data for the understanding of differences between racial groups. , Thesis (MA) -- Faculty of Humanities, Psychology, 1988
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Date Issued: 1988

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An investigation into the biological treatment of platinum refinery effluent using the plant Azolla Filiculoides

- Marran, Vernon Edward

Authors: Marran, Vernon Edward
Date: 2003
Subjects: Uncatalogued
Language: English
Type: Master's theses , text
Identifier: http://hdl.handle.net/10962/193453 , vital:45333
Description: In order to understand the effects of metals contained in effluent and to define effluent quality suitable for safe discharge to natural water streams, it is essential to understand the effects of the interaction of metal ions with plants. The availability of metal ions and their ability to bind to plants are dependent on the chemical speciation of metals and on the biological factors governing the availability of metals within the plant cells. This thesis will address both aspects and thereby propose a combination of an appropriate chemical and biological approach to the investigation of bioaccumulation of the plant Azolla Filiculoides. Laboratory studies have shown that varying concentrations of free metal ions in solution determine efficiency of metal uptake and that metal toxicity can also be detrimental to plant life and efficiency of metal recovery from solution. Many questions however, remain unanswered with regard to the application of a biological treatment for effluent discharge. This thesis includes the determination of metal speciation combined with the study of bioaccumulation of metals in plants and their effects from test- work utilising effluent generated from a Precious Metals Refinery (PMR). Plant species are known to differ widely in their tolerance to metals, however despite an abundant knowledge on molecular, biochemical and physiological effects of metals to plants, only a few general principles have been proposed to guide the prediction of tolerance differences. The properties of protective cellular responses as well as of the molecular target sites are important components in determining the intrinsic tolerance of a particular species to a metal. The role of the whole assembly of cellular ligands in buffering metal ions within the cells will be evaluated. Standard preparation methods combined with use of Inductively Coupled Plasma Emission Spectrophotometer (1CP) used for analytical analysis will be included to reflect analytical data in providing evidence to support a conclusion. The outcome of the test work utilising the aquatic plant Azoila has proven that it can be used as a process step to re-mediate effluent generated from Precious Metal Refining operations. This process offers an alternative to the classical chemical methods widely used in the Precious Metals Refining industry proving economically viable and ensuring environmental sustainability in comparison to the current known methods of effluent treatment. , Thesis (MSc) -- Faculty of Science, Biochemistry, Microbiology and Biotechnology, 2003
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Date Issued: 2003

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The reform of world order?: BRICS in an Interpolar world

- Phyllis, Yvonne

Authors: Phyllis, Yvonne
Date: 2015
Subjects: Uncatalogued
Language: English
Type: Master's theses , text
Identifier: http://hdl.handle.net/10962/193520 , vital:45339
Description: International relations has recently seen new developments which are unpredictable and in their infant stage. The causes of these developments are plentiful, the consequences stemming from waning unipolarity to the emergence of new fora creating their own spaces. Whatever the case, international relations is not as it was in the period just after the Cold War. As a result, the terms of global governance established after 1990 have come under serious scrutiny. This transition has the makings of a new world order, an interpolar world order. This study asserts that we no longer live in a unipolar world, nor do we live in a world which can only be described as multipolar. It makes the argument that although multipolarity is a crucial element of the world, it only offers a partial description of today’s order. The study asserts that it is interpolarity which is closest in accounting for today’s world. Not only does it describe the world as multipolar, it also describes it as interdependent. To this end, the study provides a detailed account of what is meant by an interpolar world order and how differently it explains international events. It also provides an account of factors which can develop in an interpolar world. One of these includes allowing room for emerging powers to create their own spaces in efforts of avoiding co-option while continuing to realise the importance of operating within a context of continuity. This means that emerging countries create their own spaces but they also realise the importance of working with already established regimes such as the G20. BRICS (Brazil, Russia, India, China and South Africa) is used as a case study to indicate one of the new developments afforded by an interpolar order-the emergence of new fora. The study asserts that although BRICS is rife with internal dissimilarities, it has indicated some degree of political will in one aspect; that is; advocating for the reform of the terms of global governance, advocating for more representative forms of global governance. The study thus explores factors of a world whose contours are gradually changing but which are unpredictable and in flux. , Thesis (MA) -- Faculty of Humanities, Political and International Studies, 2015
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Date Issued: 2015

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Repurposing a polymer precursor scaffold for medicinal application: Synthesis, characterization and biological evaluation of ferrocenyl 1,3-benzoxazine derivatives as potential antiprotozoal and anticancer agents

- Mbaba, Mziyanda

Authors: Mbaba, Mziyanda
Date: 2020
Subjects: Uncatalogued
Language: English
Type: Doctoral theses , text
Identifier: http://hdl.handle.net/10962/164502 , vital:41124 , DOI 10.21504/10962/164502
Description: The benzoxazines are a prominent class of heterocyclic compounds that possess a multitude of properties. To this end, benzoxazine derivatives have been used as versatile compounds for various utilities ranging from biological applications to the fabrication of polymers. Particularly, the 1,3-benzoxazine scaffold has featured in several bioactive compounds showing antimalarial, anticancer and antibacterial activities. Traditionally, it has been employed as a substrate in the synthesis of polymers with appealing physical and chemical properties. Due to the increasing interest in the polymer application of 1,3-benzoxazines, research of the 1,3-benzoxazine motif for polymer synthesis has been prioritized over other applications including its medicinal potential. The continuous development of resistance to clinical anticancer and antimalarial drugs has necessitated the need for the search of innovative bioactive compounds as potential alternative medicinal agents. To address this, the field of medicinal chemistry is adapting new approaches to counter resistance by incorporating nonconventional chemical moieties such as organometallic complexes, like ferrocene, into bioactive chemical motifs to serve as novel compounds with medicinal benefits. Incorporation of ferrocene into known bioactive chemical moieties has been shown to impart beneficial biological effects into the resultant compounds, which include the introduction of novel, and sometimes varied, mechanistic modalities and enhanced potency. Presented with the benefits of this strategy, the current work aims to design and evaluate the pharmaceutical capacity of novel derivatives containing 1,3-benzoxazine scaffold (traditionally applied in polymer synthesis) hybridized with the organometallic ferrocene unit as bioactive agents. Using a combination of expedient synthetic procedures such as the Burke three-component Mannich-type condensation, Vilsmeier-Haack formylation and reductive amination, four series of ferrocenyl 1,3-benzoxazine derivatives were synthesized and their structures confirmed by common spectroscopic techniques: nuclear magnetic resonance (NMR), infrared spectroscopy (IR) and high-resolution mass spectrometry (HRMS). The target compounds were evaluated in vitro for potential antimalarial and anticancer activities against strains of the malaria parasite (Plasmodium falciparum 3D7 and Dd2) and the triple-negative breast cancer cell line HCC70. Compounds exhibited higher potency towards the Plasmodium falciparum strains with IC50 values in the low and sub-micromolar range in comparison to the breast cancer cell line against for which mid-molar activities were observed. To gain insight into the possible mode of action of ferrocenyl 1,3-benzoxazines, representative compounds showing most efficacy from each series were assessed for DNA binding affinity by employing UV-Vis and fluorescence DNA titration experiments. The selected compounds were found to interact with the DNA by binding to the minor groove, and these findings were confirmed by in silico ligand docking studies using a B-DNA structure as the receptor. Compound 3.16c (IC50: 0.261 μM [3D7], 0.599 μM [Dd2], 11.0 μM [HCC70]), which emerged as the most promising compound, was found to induce DNA damage in HCC70 cancer cells when investigated for effects of DNA interaction. Additionally, compound 3.16c displayed a higher binding constant (Kb) against DNA isolated from 3D7 Plasmodium falciparum trophozoites (Kb = 1.88×106 M-1) than the mammalian DNA (Kb = 6.33×104 M-1) from calf thymus, thus explaining the preferred selectivity of the compounds for the malaria parasite. Moreover, the investigated compounds demonstrated binding affinity for synthetic hemozoin, β-hematin. Collectively, these data suggest that the compounds possess a dual mode of action for antimalarial activity involving DNA interaction and hemozoin inhibition. , Thesis (PhD) -- Faculty of Science, Chemistry, 2020
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Date Issued: 2020

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Self-reports on the effectiveness of psychotherapy with therapists-in-training: an 18-month follow-up study at a psychology training clinic

- Angus, Catherine Clare

Authors: Angus, Catherine Clare
Date: 1993
Subjects: Uncatalogued
Language: English
Type: Master's theses , text
Identifier: http://hdl.handle.net/10962/193069 , vital:45295
Description: The purpose of this study is to ascertain whether the clients who make use of the services of the Psychology Clinic at Rhodes University perceive the masters students being trained at the Clinic as providing adequate psychotherapy. Using a sample of 18 clients, who underwent psychotherapy at the Rhodes Psychology Clinic during 1990, a follow-up study was conducted to ascertain the perceived success of that psychotherapy. Those variables most pertinent to the outcome of psychotherapy are examined. The study uses both qualitative and quantitative methodology and shows that, overall, 89% of the clients who participated in this study perceived the psychotherapy at the Rhodes Psychology Clinic to be satisfactory. The study also highlights those factors which were perceived to be negative in the psychotherapeutic equation and it is hoped that the findings can be beneficial in planning more efficient services for the Clinic in the future. , Thesis (MA) -- Faculty of Humanities, Psychology, 1993
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Date Issued: 1993

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