List of Titles

Bioinformatics tool development with a focus on structural bioinformatics and the analysis of genetic variation in humans

- Brown, David K

Authors: Brown, David K
Date: 2018
Subjects: Bioinformatics , Human genetics -- Variation , High performance computing , Workflow management systems , Molecular dynamics , Next generation sequencing , Human Mutation Analysis (HUMA)
Language: English
Type: text , Thesis , Doctoral , PhD
Identifier: http://hdl.handle.net/10962/60708 , vital:27820
Description: This thesis is divided into three parts, united under the general theme of bioinformatics tool development and variation analysis. Part 1 describes the design and development of the Job Management System (JMS), a workflow management system for high performance computing (HPC). HPC has become an integral part of bioinformatics. Computational methods for molecular dynamics and next generation sequencing (NGS) analysis, which require complex calculations on large datasets, are not yet feasible on desktop computers. As such, powerful computer clusters have been employed to perform these calculations. However, making use of these HPC clusters requires familiarity with command line interfaces. This excludes a large number of researchers from taking advantage of these resources. JMS was developed as a tool to make it easier for researchers without a computer science background to make use of HPC. Additionally, JMS can be used to host computational tools and pipelines and generates both web-based interfaces and RESTful APIs for those tools. The web-based interfaces can be used to quickly and easily submit jobs to the underlying cluster. The RESTful web API, on the other hand, allows JMS to provided backend functionality for external tools and web servers that want to run jobs on the cluster. Numerous tools and workflows have already been added to JMS, several of which have been incorporated into external web servers. One such web server is the Human Mutation Analysis (HUMA) web server and database. HUMA, the topic of part 2 of this thesis, is a platform for the analysis of genetic variation in humans. HUMA aggregates data from various existing databases into a single, connected and related database. The advantages of this are realized in the powerful querying abilities that it provides. HUMA includes protein, gene, disease, and variation data and can be searched from the angle of any one of these categories. For example, searching for a protein will return the protein data (e.g. protein sequences, structures, domains and families, and other meta-data). However, the related nature of the database means that genes, diseases, variation, and literature related to the protein will also be returned, giving users a powerful and holistic view of all data associated with the protein. HUMA also provides links to the original sources of the data, allowing users to follow the links to find additional details. HUMA aims to be a platform for the analysis of genetic variation. As such, it also provides tools to visualize and analyse the data (several of which run on the underlying cluster, via JMS). These tools include alignment and 3D structure visualization, homology modeling, variant analysis, and the ability to upload custom variation datasets and map them to proteins, genes and diseases. HUMA also provides collaboration features, allowing users to share and discuss datasets and job results. Finally, part 3 of this thesis focused on the development of a suite of tools, MD-TASK, to analyse genetic variation at the protein structure level via network analysis of molecular dynamics simulations. The use of MD-TASK in combination with the tools developed in the previous parts of this thesis is showcased via the analysis of variation in the renin-angiotensinogen complex, a vital part of the renin-angiotensin system.
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Biological activities of plant extracts from Ficus elastica and Selaginella vogelli: an antimalarial, antitrypanosomal and cytotoxity evaluation

- Meyer, Franck, Isaacs, Michelle, Noundou, Xavier S, Krause, Rui W M, Teinkela, J E M, Hoppe, Heinrich C, Mpondo, Albert E M, Azebaze, Anatole G B, Nguemfo, Edwige L, Wintjens, Rene

Authors: Meyer, Franck , Isaacs, Michelle , Noundou, Xavier S , Krause, Rui W M , Teinkela, J E M , Hoppe, Heinrich C , Mpondo, Albert E M , Azebaze, Anatole G B , Nguemfo, Edwige L , Wintjens, Rene
Date: 2018
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/126142 , vital:35853 , https://doi.org/10.1016/j.sjbs.2017.07.002
Description: The cytotoxic, antiplasmodial, and antitrypanosomal activities of two medicinal plants traditionally used in Cameroon were evaluated. Wood of Ficus elastica Roxb. ex Hornem. aerial roots (Moraceae) and Selaginella vogelii Spring (Selaginellaceae) leaves were collected from two different sites in Cameroon. In vitro cell-growth inhibition activities were assessed on methanol extract of plant materials against Plasmodium falciparum strain 3D7 and Trypanosoma brucei brucei, as well as against HeLa human cervical carcinoma cells. Criteria for activity were an IC50 value 10 μg/mL. The extract of S. vogelii did not significantly reduce the viability of P. falciparum at a concentration of 25 μg/mL but dramatically affected the trypanosome growth with an IC50 of 2.4 μg/mL. In contrast, at the same concentration, the extract of F. elastica exhibited plasmodiacidal activity (IC50 value of 9.5 μg/mL) and trypanocidal (IC50 value of 0.9 μg/mL) activity. Both extracts presented low cytotoxic effects on HeLa cancer cell line. These results indicate that the selected medicinal plants could be further investigated for identifying compounds that may be responsible for the observed activities and that may represent new leads in parasitical drug discovery.
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Biological activity of plant extracts and isolated compounds from Alchornea laxiflora: Anti-HIV, antibacterial and cytotoxicity evaluation

- Ndinteh, Derek T, Olivier, Denise K, Noundou, Xavier S, Krause, Rui W M, Mnkandhla, D, Isaacs, Michelle, Hoppe, Heinrich C, Muganza, F M, Mbafor, J T, Van Vuuren, S F, Patnala, S

Authors: Ndinteh, Derek T , Olivier, Denise K , Noundou, Xavier S , Krause, Rui W M , Mnkandhla, D , Isaacs, Michelle , Hoppe, Heinrich C , Muganza, F M , Mbafor, J T , Van Vuuren, S F , Patnala, S
Date: 2018
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/126634 , vital:35907 , https://doi.org/10.1016/j.sajb.2018.08.010
Description: This study was designed to assess the cytotoxicity, anti-HIV and antibacterial efficacy of various solvent extracts of roots, stem and leaves of Alchornea laxiflora, as well as five compounds isolated from its methanolic stem extract viz.; ellagic acid (1); 3-O-methyl-ellagic acid (2), 3-O-β-d-glucopyranosyl-β-sitosterol (3), 3-O-acetyl-oleanolic acid (4) and 3-O-acetyl-ursolic acid (5). The tested crude extracts were prepared from several solvent polarities including: hexane (Hex), chloroform (CHCl3), ethyl acetate (EtOAc), ethanol (EtOH), methanol (MeOH) and water (H2O). The anti-HIV properties were assessed on HIV-1 subtype C integrase while the cytotoxicity was tested against Hela cells. The antibacterial activity was studied on a panel of pathogens including gastrointestinal, skin, respiratory and urinary-tract infection causing Gram positive bacteria viz.; Bacillus cereus (ATCC 11778), Enterococcus faecalis (ATCC 29212), Staphylococcus aureus (ATCC 25923) and Staphylococcus saprophyticus (ATCC 15305)] and Gram-negative bacteria, i.e., Escherichia coli (ATCC 25922), Klebsiella pneumoniae (ATCC 13883), Moraxella catarrhalis (ATCC 23246). All the tested samples were determined to be non-toxic due to the low inhibitions observed. The most potent anti-HIV activity was observed for the methanolic extract of A. laxiflora root (ALR4) with an IC50 value of 0.21 ng/ml, which was more active than chicoric acid used as reference drug (6.82 nM). Roots, stem and leaves of A. laxiflora extracts exhibited antibacterial activities against most of the Gram-positive bacteria with the minimum inhibitory concentrations (MIC) ranging between 50 and 63 μg/ml. Compounds 1–5 displayed antibacterial activities against S. saprophyticus with MIC values as low as 4 μg/ml. The results inferred from this study demonstrate the potential of A. laxiflora root as a source for new anti-HIV drugs and scientifically validate the traditional use of A. laxiflora in the treatment of gastrointestinal, skin, respiratory and urinary tract related infections. These results reaffirm the ethnopharmacological significance of African traditional medicines.
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Biological control of Salvinia molesta in South Africa revisited

- Martin, Grant D, Coetzee, Julie A, Weyl, Philip S R, Parkinson, Matthew C, Hill, Martin P

Authors: Martin, Grant D , Coetzee, Julie A , Weyl, Philip S R , Parkinson, Matthew C , Hill, Martin P
Date: 2018
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/103878 , vital:32318 , https://doi.org/10.1016/j.biocontrol.2018.06.011
Description: The aquatic weed Salvinia molesta D.S. Mitch. (Salviniaceae) was first recorded in South Africa in the early 1900s, and by the 1960s was regarded as one of South Africa’s worst aquatic weeds. Following the release of the weevil, Cyrtobagous salviniae Calder and Sands (Coleoptera: Curculionidae) in 1985, the weed is now considered under successful biological control. However, the post-release evaluation of this biological control programme has been ad hoc, therefore, to assess the efficacy of the agent, annual quantitative surveys of South African freshwater systems have been undertaken since 2008. Over the last ten years, of the 57 S. molesta sites visited annually in South Africa, the weevil has established at all of them. Eighteen sites are under successful biological control, where the weed no longer poses a threat to the system and 19 are under substantial biological control, where biological control has reduced the impact of the weed. Since 2008, the average percentage weed cover at sites has declined significantly from 51–100% cover to 0–5% cover in 2017 (R2 = 0.78; P < 0.05). Observations of site-specific characteristics suggest that biological control is most effective at small sites and more difficult at larger and shaded sites. Our findings show that S. molesta remains under good biological control in South Africa, however, some sites require intermittent strategic management, such as augmentative releases of C. salviniae.
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Bioprospecting for amylases, cellulases and xylanases from ericoid associated fungi, their production and characterisation for the bio-economy

- Adeoyo, Olusegun Richard

Authors: Adeoyo, Olusegun Richard
Date: 2018
Subjects: Mycorrhizal fungi , Hydrolases , Ericaceae South Africa , Ericaceae Molecular aspects
Language: English
Type: Doctoral theses , text
Identifier: http://hdl.handle.net/10962/64327 , vital:28533
Description: South Africa is one of the most productive areas for ericaceous plants with about 850 identified species in the Cape Floral Region. The Albany Centre of Endemism where all fungi used in this study were isolated from, falls within this region. Ericaceous plants interact with some fungi via an association called the ericoid mycorrhizal (ERM) association. All fungi used in this study were isolated from roots of six ericaceous plants; Erica cerinthoides, Erica demissa, Erica chamissonis, Erica glumiflora, Erica caffra and Erica nemorosa. Fungal enzymes are known to play a significant role in the food, brewing, detergent, pharmaceutical and biofuel industries. The enzyme industry is among the major sectors of the world, and additional novel sources are being explored from time to time. This study focussed on amylases (amyloglucosidase, AMG), cellulases (endoglucanase) and xylanases (endo-1,4-P-xylanase) production from ERM fungal isolates. Out of the fifty-one (51), fungal isolates screened, ChemRU330 (Leohumicola sp.), EdRU083 and EdRU002 were among the fungi that had the highest activities of all the enzymes. They were tested for the ability to produce amylases and cellulases under different pH and nutritional conditions that included: carbon sources, nitrogen sources and metal ions, at an optimum temperature of 28°C in a modified Melin-Norkrans (MMN) liquid medium. Cellulase specific activity of 3.99, 2.18 and 4.31 (U/mg protein) for isolates EdRU083, EdRU002 and ChemRU330, respectively, was produced at an optimal pH of 5.0. For amylase, ChemRU330 had the highest specific activity of 1.11 U/mg protein while EdRU083 and EdRU02 had a specific activity of 0.80 and 0.92 U/mg protein, respectively, at the same pH with corresponding biomass yield of 113, 125 and 97 mg/50 ml, respectively. Increased enzyme activities and improved mycelial biomass production were obtained in the presence of supplements such as potassium, sodium, glucose, maltose, cellobiose, tryptone and peptone, while NaFe-EDTA and cobalt inhibited enzyme activity. ChemRU330 was selected to determine the consistency and amount of amylase, cellulase and xylanase formed after several in vitro subculturing events. AMG and endo-1,4-P-xylanase were found to have the most consistent production throughout the study period. The AMG was stable at 45oC (pH 5.0), retaining approximately 65% activity over a period of 24 h. The molecular mass of AMG and endo-1,4-P-xylanase were estimated to be 101 kDa and 72 kDa, respectively. The Km and kcat were 0.38 mg/ml and 70 s-1, respectively, using soluble starch (AMG). For endo-1,4-P-xylanase, the Km and Vmax were 0.93 mg/ml and 8.54 U/ml, respectively, using beechwood xylan (endo-1,4-P-xylanase) as substrate. Additionally, crude extracts of five root endophytes with unique morphological characteristics were screened for antibacterial properties and was followed by determination of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). L. incrustata (ChemRU330) and Chaetomium sp. extracts exhibited varying degrees of inhibition against two Gram-positive and Gram-negative bacteria. The crude extract of L. incrustata was the most effective which was found to inhibit Staphylococcus aureus (MIC: 1 mg/ml), Bacillus subtilis (MIC: 2 mg/ml) and Proteus vulgaris (MIC: 16 mg/ml). The L. incrustata displayed potential for antibacterial production and could be considered as an additional source of new antimicrobial agents in drug and food preservation. Also, the three isolates used for enzyme production were identified to genus and species levels, i.e., Leohumicola incrustata (ChemRU330), Leohumicola sp. (EdRU083) and Oidiodendron sp. (EdRU002) using both ITS and Cox1 DNA regions. The molecular analysis results indicated that these ERM mycorrhizal fungi were similar to those successfully described by some researchers in South Africa and Australia. Therefore, this study opens new opportunities for exploring ERM fungal biomolecules for the bio-economy. The promising physicochemical properties, starch and xylan hydrolysis end- products, and being non-pathogenic make AMG and endo-1,4-P-xylanase potential candidates for future applications as additives in the food industry for the production of glucose, glucose syrups, high-fructose corn syrups, and as well as the production of bioethanol. Finally, the findings of this study revealed that it is possible to produce hydrolytic enzymes from ERM fungi in vitro using chemically defined media. , Thesis (PhD) -- Faculty of Science, Biochemistry and Microbiology, 2018
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Biotic and abiotic drivers of macroinvertebrate assemblages in a South African river

- Bellingan, Terence Andrew

Authors: Bellingan, Terence Andrew
Date: 2018
Subjects: Aquatic insects -- South Africa -- Eastern Cape , Stream ecology -- South Africa -- Eastern Cape , Freshwater ecology -- South Africa -- Eastern Cape , Riparian areas -- Management , Ecosystem management -- South Africa -- Eastern Cape , Mayflies -- South Africa -- Eastern Cape , Stoneflies -- South Africa -- Eastern Cape , Keiskamma River
Language: English
Type: text , Thesis , Doctoral , PhD
Identifier: http://hdl.handle.net/10962/61839 , vital:28067
Description: Aquatic insects are the most numerically abundant and diverse group of organisms found in lotic ecosystems in South Africa and the world over. They play vital roles in freshwater ecosystem functioning, processing nutrients and in turn forming integral links in stream food-webs. This thesis focussed on examining the macroinvertebrate fauna within three reaches of headwater streams of the Keiskamma River system: reaches that were considered to be fishless; reaches that were invaded by non-native salmonid species; and reaches that were dominated by native fish. I described the effects of predatory fish presence through detailed examination of macroinvertebrate assemblage composition; macroinvertebrate drift timing and density; and through niche utilisation determined from stable isotope data. Patterns in the macroinvertebrate assemblages of the headwaters of the Keiskamma River appear to be driven more strongly by flow rate and seasonal influences, but fish presence and biotope availability were also significant drivers. Niche shifts due to predator presence were not easy to detect and, while patterns of influence may have been evident, they were not found to be significant. However, I demonstrated that salmonids selectively feed on native fish species when the opportunity is presented, occupying significantly higher trophic levels when co-occurring with native fish than in invaded reaches where native fish are absent. Drift timing and density were demonstrated to be significantly different between reach for specific macroinvertebrate species from the Ephemeroptera and Plecoptera, under differing fish predation regimes, in agreement with what has been observed from studies in rivers elsewhere. In freshwater ecosystems of South Africa and worldwide, mitigation of negative effects of alien fishes through their removal using piscicides may also affect non-target organisms. To better understand the effects of just such a removal operation, employed for the first time in the history of freshwater conservation in South Africa, macroinvertebrate communities were assessed for non-target effects of rotenone. The fish eradication operations were demonstrated to have a short-term negative effect on the macroinvertebrate assemblage, through water quality index measurements and alteration of densities of macroinvertebrate taxa collected from stone surfaces. However, no long-term detrimental impact was observed as macroinvertebrate faunas returned to a comparable pre-treatment state within a year of each rotenone application.
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Bird responses to land use change: Guild diversity in a Kenyan coastal forest and adjoining habitats

- Chiawo, David O, Kombe, Wellington N, Craig, Adrian J F K

Authors: Chiawo, David O , Kombe, Wellington N , Craig, Adrian J F K
Date: 2018
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/448820 , vital:74763 , https://doi.org/10.1080/01584197.2018.1431052
Description: Land use change can have profound effects on forest ecology, particularly on the avian community. Arabuko-Sokoke Forest, one of the Important Bird Areas (IBAs) in Kenya, is under threat due to ongoing land use change in the surroundings that could affect species composition of many bird guilds. However, information on the response of different guilds in tropical land use systems is sparse in Africa. We examined the effects of land use on bird guilds in primary forest (Arabuko-Sokoke Forest), adjoining plantations, and neighbouring farmland. Point counts were distributed equally in the three land use systems to survey bird populations. A total of 2600 bird observations was recorded, representing 97 species in five main feeding guilds (frugivores, nectarivores, insectivores, carnivores, and granivores). Granivores were most abundant and diverse in farmland, while carnivores (primarily raptors) utilised all habitats. Insectivores were most diverse in primary forest where vertical heterogeneity of the vegetation and the presence of large fruiting trees significantly influenced their occurrence. Specialist nectarivores were most frequent in primary forest, whereas occasional nectarivores were less abundant there. Contrary to expectation, frugivore diversity showed no significant effect of land use.
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Black university students’ experiences of negotiating their social identity in a historically white university

- Mogotsi, Opelo Petunia

Authors: Mogotsi, Opelo Petunia
Date: 2018
Subjects: Corporate culture -- South Africa , Social integration -- South Africa , Race discrimination -- South Africa , Segregation in higher education -- South Africa , Group identity -- South Africa , College students, Black -- South Africa , Biko, Steve, 1946-1977 , Fanon, Frantz, 1925-1961
Language: English
Type: text , Thesis , Masters , MA
Identifier: http://hdl.handle.net/10962/62416 , vital:28174
Description: This thesis seeks to explore the social identity of black students in a historically white university. Since 1994, South African government has been promulgating pieces of legislation aimed at ensuring racial integration, and indirectly enforcing acculturation in historically white universities. Studies have proven that institutional cultures in historically white universities alienate and exclude black students’ identities. These students’ sense of social identity, which includes amongst others; culture, heritage, language and traditions, and consequently self-esteem and self-concept is altered in these institutions. Research has been scant regarding the shape and form that black students’ identity assume when they get to these spaces. Face to face interviews were used to collect data and thematic analysis was used for data analysis. The Social Identity and the Acculturation models were used to explore the experiences of black students in negotiating their social identities in a historically white university. Evoking Steve Biko’s analysis of ‘artificial integration’, it was illustrated how the ‘integration’ narrative sought to discard the identity of black students and psychologically enforce a simulation of black students into white established identities. The main themes discussed indicated that black students in this study had social identity and identity challenges in a historically white university. This study has implications for policy development as I hope to theoretically sensitize historically white universities to (apart from mere opening of spaces of learning) understand the social identity challenges of black students.
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Black, white and everything in-between: Unravelling the times with Zoë Wicomb

- Phiri, Aretha

Authors: Phiri, Aretha
Date: 2018
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/458474 , vital:75747 , https://hdl.handle.net/10520/EJC-1061dd5e30
Description: Born in Namaqualand in the Western Cape in 1948, Zoë Wicomb is one of South Africa’s most accomplished and celebrated writers. With five published works of fiction, including two short story collections, and a body of critical scholarly essays to her name to date, she is an indisputable part of the South African English literary canon. Her fiction, which is typically taught in secondary and tertiary educational institutions and is the focus of considerable academic study, forms an intricate, if provocative, part of the South African literary landscape.
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Blending problem-based learning and peer-led team learning, in an open ended ‘home-grown’pharmaceutical chemistry case study

- Sewry, Joyce D, Veale, Clinton G L, Krause, Rui W M

Authors: Sewry, Joyce D , Veale, Clinton G L , Krause, Rui W M
Date: 2018
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/125691 , vital:35809 , https://doi.org/10.1039/C7RP00180K
Description: Pharmaceutical chemistry, medicinal chemistry and the drug discovery process require experienced practitioners to employ reasoned speculation in generating creative ideas, which can be used to evolve promising molecules into drugs. The ever-evolving world of pharmaceutical chemistry requires university curricula that prepare graduates for their role as designers with the capability of applying complex concepts in pharmaceutical chemistry, thereby improving the decision-making process. Common methods of teaching drug discovery, including the linear nature of the traditional case study model, do not provide a realistic picture of the underlying complexity of the process, nor do they equip students with the appropriate tools for personal sense making and abstraction. In this work, we discuss the creation of an open-ended, nonlinear case study for 3rd year pharmaceutical chemistry students, developed from drug discovery research conducted at Rhodes University. Furthermore, we discuss blending problem based learning (PBL) with peer-led team learning (PLTL) in the context of curriculum transformation, underpinned by the theory of semantic waves, to assist students in the early attainment of abstract concepts and answer questions of contextualisation, personal sense making, relatability, relevance and ultimately the skills for lifelong learning.
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Blue ring of fire

- O’Flaherty, Craig

Authors: O’Flaherty, Craig
Date: 2018
Subjects: Creative writing (Higher education) -- South Africa , South African poetry (English) -- 21st century
Language: English
Type: text , Thesis , Masters , MA
Identifier: http://hdl.handle.net/10962/63615 , vital:28448
Description: My poems are reflections of shape, colour and emotions expressed through imagery. Their unsentimental landscape-realism echo my own feelings as well as broader human dimensions of contradiction and uncertainty, without trying to resolve them. In the same way that photography is the art of 'painting with light', my poems seek a language that evokes light and darkness. They aspire to what Keats said when writing about ‘negative capability’: “Poetical character has no self, it is anything and nothing, it has no character and enjoys light and shade”. My poems explore what I have learned about form – how line-length, syntax and musicality can add grace and energy to language. Poets that have influenced me include the classical Chinese poets such as Du Fu and Li Po, and the Generation of 27 Spanish poets, such as Antonio Machado and Leon Felipe.
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Bodies, buildings, and borders: navigating the divided nation through contemporary South African and Palestinian art practice

- Baasch, Rachel M

Authors: Baasch, Rachel M
Date: 2018
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/145897 , vital:38476 , https://0-doi.org.wam.seals.ac.za/10.1162/afar_a_00401
Description: This paper navigates the phenomenon of the divided nation through the work of contemporary South African artists Th¬ando Mama, Sikhumbuzo Makandula, and Ndikhumbule Ngqinambi. I position the work of these artists practicing in a post-apartheid nation-state alongside the work of contemporary Palestinian artists Larissa Sansour and Khaled Jarrar, who respond to the ongoing struggle of the stateless Palestinian nation divided by colonialism and Israeli apartheid. Each of these artists critiques the construction of the modern nation-state using symbols such as the national flag, the national anthem, the passport and postage stamp, and physical walls and buildings.
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BODIPY dyes for singlet oxygen and optical limiting applications

- Harris, Jessica

Authors: Harris, Jessica
Date: 2018
Subjects: Photosensitizing compounds , Active oxygen -- Physiological effect , Photochemotherapy , Cancer -- Treatment , Nonlinear optics , BODIPY (Boron-dipyrromethene)
Language: English
Type: text , Thesis , Masters , MSc
Identifier: http://hdl.handle.net/10962/58002 , vital:27014
Description: A series of structurally related BODIPY dyes were synthesised and characterised. Their photophysical properties were studied in order to determine whether they would be suitable candidates for use as photosensitisers in the photodynamic therapy (PDT) treatment of cancer. The synthesis of two highly fluorescent BODIPY cores was achieved via the acid-catalysed condensation of a pyrrole and a functionalised aldehyde. In order to promote intersystem crossing, and hence improve the singlet oxygen generation of these dyes, bromine atoms were added at the 2,6-positions of the BODIPY core. These dibrominated analogues showed good singlet oxygen quantum yields, and excellent photostability in ethanol. In order to red-shift the main spectral bands of the BODIPY dyes towards the therapeutic window, vinyl/ styryl groups were introduced at the 3-, 5-, and 7-positions via a modified Knoevengal condensation reaction. The addition of vinyl/ styryl groups to the BODIPY core caused an increase in fluorescence quantum yield as well as a decrease in singlet oxygen quantum yield with respect to the dibrominated analogues. However, two of the red-shifted BODIPY dyes still showed moderate singlet oxygen quantum yields. The use of BODIPY dyes in nonlinear optics (NLO) was explored. The nonlinear optical characterisations and optical limiting properties of a series of 3,5-dithienylenevinylene BODIPY dyes were studied, both in dimethylformamide (DMF) solution and when embedded in poly(bisphenol A carbonate) (PBC) as thin films. The 3,5-dithienylenevinylene BODIPY dyes showed typical nonlinear absorption behaviour, with reverse saturable absorption (RSA) profiles, indicating that they have potential as optical limiters. The second-order hyperpolarizability (Y), and third-order nonlinear susceptibility (/m[/(3)]) values are also reported for these dyes. The optical limiting values of one of the BODIPY dyes in solution, and two of the BODIPY-embedded PBC films, were below the maximum threshold of 0.95 J-cm-2. The effect of addition of substituents on the electronic structure of the BODIPY dyes was investigated using TD-DFT calculations. The calculated trends closely followed those determined experimentally.
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Bollywood Nights: Indian youth and the creation of diasporic identity in South Africa

- Boshoff, Priscilla A

Authors: Boshoff, Priscilla A
Date: 2018
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/143494 , vital:38251 , DOI: 10.3138/topia.26.29
Description: Bollywood’s popularity as a global cultural form has occurred at the same time as the valorization of difference in the South African political landscape. As the youngest members of the 19th-century labour diaspora, South African Indian youths are the inheritors of a conservative—yet adaptable—home culture amidst the marginalized identities of (post-)apartheid South Africa. Their desire to create an identity for themselves that encompasses their self-perception both as modern South African subjects and as guardians of their traditional home cultures is achieved through Bollywood, which speaks to its diasporic audiences through images of an idealized traditional yet modern India. While India is not a place of return for these youth, their reactivation of a diasporic identity through Bollywood’s representations of a successful Indian diasporic culture and their participation in South African Bollywood concerts and award ceremonies has provided an opportunity for young South African Indians to reimagine their diasporic Indian identity in ways that (re-)connect them to India and to an imagined global diaspora.
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Bringing us back

- Dhliwayo, Mercy

Authors: Dhliwayo, Mercy
Date: 2018
Subjects: South African fiction (English) -- 21st century , Short stories, South African (English) -- 21st century
Language: English
Type: text , Thesis , Masters , MA
Identifier: http://hdl.handle.net/10962/63077 , vital:28361
Description: My thesis takes the form of a collection of short stories set mostly in Zimbabwe and South Africa under the current political, social and economic climate. The themes I explore include forced migrations, identity, family disintegration and destitution. I use non-linear narration inspired by my reading of Dambudzo Marechera and Lidia Yuknavitch’s use of photographic imagery, in Black Sunlight and The Small Backs of Children respectively, to heighten my thematic concerns. The poetry in their language also serves as a source of inspiration, as does the graphic imagery used by Ayi Kwei Armah. In addition, I draw on the fragmented form used by Deepak Unnikrishnan to explore migration in his collection, Temporary People and Miljenko Jergovic’s investigation of violence and displacement in Sarajevo Marlboro.
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Building IKhwezi, a digital platform to capture everyday Indigenous Knowledge for improving educational outcomes in marginalised communities

- Ntšekhe, Mathe V K

Authors: Ntšekhe, Mathe V K
Date: 2018
Subjects: Information technology , Knowledge management , Traditional ecological knowledge , Pedagogical content knowledge , Traditional ecological knowledge -- Technological innovations , IKhwezi , ICT4D , Indigenous Technological Pedagogical Content Knowledge (I-TPACK) , Siyakhula Living Lab
Language: English
Type: text , Thesis , Doctoral , PhD
Identifier: http://hdl.handle.net/10962/62505 , vital:28200
Description: Aptly captured in the name, the broad mandate of Information and Communications Technologies for Development (ICT4D) is to facilitate the use of Information and Communication Technologies (ICTs) in society to support development. Education, as often stated, is the cornerstone for development, imparting knowledge for conceiving and realising development. In this thesis, we explore how everyday Indigenous Knowledge (IK) can be collected digitally, to enhance the educational outcomes of learners from marginalised backgrounds, by stimulating the production of teaching and learning materials that include the local imagery to have resonance with the learners. As part of the exploration, we reviewed a framework known as Technological Pedagogical Content Knowledge (TPACK), which spells out the different kinds of knowledge needed by teachers to teach effectively with ICTs. In this framework, IK is not present explicitly, but through the concept of context(s). Using Afrocentric and Pan-African scholarship, we argue that this logic is linked to colonialism and a critical decolonising pedagogy necessarily demands explication of IK: to make visible the cultures of the learners in the margins (e.g. Black rural learners). On the strength of this argument, we have proposed that TPACK be augumented to become Indigenous Technological Pedagogical Content Knowledge (I-TPACK). Through this augumentation, I-TPACK becomes an Afrocentric framework for a multicultural education in the digital era. The design of the digital platform for capturing IK relevant for formal education, was done in the Siyakhula Living Lab (SLL). The core idea of a Living Lab (LL) is that users must be understood in the context of their lived everyday reality. Further, they must be involved as co-creators in the design and innovation processes. On a methodological level, the LL environment allowed for the fusing together of multiple methods that can help to create a fitting solution. In this thesis, we followed an iterative user-centred methodology rooted in ethnography and phenomenology. Specifically, through long term conversations and interaction with teachers and ethnographic observations, we conceptualized a platform, IKhwezi, that facilitates the collection of context-sensitive content, collaboratively, and with cost and convenience in mind. We implemented this platform using MediaWiki, based on a number of considerations. From the ICT4D disciplinary point of view, a major consideration was being open to the possibility that other forms of innovation—and, not just ‘technovelty’ (i.e. technological/- technical innovation)—can provide a breakthrough or ingenious solution to the problem at hand. In a sense, we were reinforcing the growing sentiment within the discipline that technology is not the goal, but the means to foregrounding the commonality of the human experience in working towards development. Testing confirmed that there is some value in the platform. This is despite the challenges to onboard users, in pursuit of more content that could bolster the value of everyday IK in improving the educational outcomes of all learners.
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