Featuring simplicity: jargon and access in contemporary South African art
- Authors: Bereng, Lerato
- Date: 2018
- Language: English
- Type: text , Thesis , Masters , MFA
- Identifier: http://hdl.handle.net/10962/60479 , vital:27784
- Description: The focus of this paper is an exploration of curating and its various forms as understood in a South African art context. In order to understand this context I examine definitions of South African publics as well as different curatorial models. I raise questions around art and accessibility as well as the functions of language as a gate keeper within the visual arts. Through a practical exploration of curatorial methods of engagement, I assess the curator's role as disseminator of information. My final project Conversations at Morija that was held in Morija, Lesotho faces the challenge of curating within a space that has a strong creative platform, but lacks a visual art audience. The exhibition was held during the 2013 Morija Art and Culture festival which is dominated by its music component. Despite Morija being the country's creative centre and sole museum, there is little support for its programme both monetary and in terms of attendance. Through a series of conversations several issues pertaining to Morija, Lesotho and the diaspora were addressed. I look at the absence of creative platforms and alternative curatorial methods that engage the public in a participatory manner. Briefly exploring questions of migrant labour and definitions of what constitutes a diaspora. I look at relatable ways to engage the local audience whilst maintaining a creative core in which to spark dialogue around pertinent matters relating to the country.
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- Date Issued: 2018
Formulation of an enzyme cocktail, HoloMix, using cellulolytic and xylanolytic enzyme core-sets for effective degradation of various pre-treated hardwoods
- Authors: Malgas, Samkelo
- Date: 2018
- Subjects: Biomass , Cellulase , Hardwoods , Xylanases
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/62827 , vital:28297 , DOI https://doi.org/10.21504/10962/62827
- Description: Currently, there is a growing interest in utilising hardwoods as feedstocks for bioethanol production due to the vast advantages they have over other feedstocks for fermentable sugar production. In this study, two selected hardwoods, Acacia and Populus spp., were subjected to two pre-treatment processes (Sodium chlorite delignification and Steam explosion) and compared with respect to how these pre-treatments affect their enzymatic saccharification. Hardwoods were selected for this study, because hardwoods are easier to delignify when compared to softwoods, and therefore their polysaccharides are more easily accessible by enzymes for the purpose of producing fermentable sugars. Currently available commercial enzyme mixtures have been developed for optimal hydrolysis of acid-pre-treated corn stover and are therefore not optimal for saccharification of pre-treated hardwoods. In this work, we attempted the empirical design of a hardwood specific enzyme cocktail, HoloMix. Firstly, a cellulolytic core-set, CelMix (in a ratio of Egl 68%: Cel7A 17%: Cel6A 6%: Bgl1 9%), for the optimal release of glucose, and a xylanolytic core-set, XynMix (in a ratio of Xyn2A 60%: XT6 20%: AguA 11%: SXA 9%), for the optimal release of xylose, were formulated using an empirical enzyme ratio approach after biochemically characterising these enzymes. As it is well ̶ known that biomass pre-treatment may result in the generation of compounds that hamper enzymatic hydrolysis and microbial fermentation, the effects of these compounds on CelMix and XynMix were evaluated. Using the optimised CelMix and XynMix cocktails, a HoloMix cocktail was established for optimal reducing sugar, glucose and xylose release from the various pre-treated hardwoods. For delignified biomass, the optimized HoloMix consisted of CelMix to XynMix at 75% to 25% protein loading, while for the untreated and steam exploded biomass the HoloMix consisted of CelMix to XynMix at 93.75% to 6.25% protein loading. Sugar release by the HoloMix at a loading of 27.5 mg protein/g of biomass (or 55 mg protein/g of glucan) after 24 h gave 70-100% sugar yield. Treatment of the hardwoods with a laccase from Agaricus bisporus, especially wood biomass with a higher proportion of lignin, significantly improved saccharification by the formulated HoloMix enzyme cocktails. This study provided insights into the enzymatic hydrolysis of various pre-treated hardwood substrates and assessed whether the same lignocellulolytic cocktail can be used to efficiently hydrolyse different hardwood species. The present study also demonstrated that the hydrolysis efficiency of the optimised HoloMix was comparable to (if not better) than commercial enzyme preparations during hardwood biomass saccharification. , Thesis (PhD) -- Faculty of Science, Biochemistry and Microbiology, 2018
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- Date Issued: 2018
Formulation, characterisation and optimisation of self-nanoemulsifying drug delivery systems (SNEDDS) loaded with artemether and lumefantrine
- Authors: Mudyahoto, Tsitsi
- Date: 2018
- Subjects: Uncatalogued
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/63503 , vital:28422
- Description: Expected release date-April 2020
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- Date Issued: 2018
From deviant choice to feminist issue: An historical analysis of scholarship on voluntary childlessness (1920–2013)
- Authors: Lynch, Ingrid , Morison, Tracy , Macleod, Catriona I , Mijas, Magdalena , du Toit, Ryan , Shivakumar, Seemanthini T
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/434319 , vital:73048 , ISBN 978-1-78754-361-4 , https://www.emerald.com/insight/content/doi/10.1108/978-1-78754-361-420181002/full/html
- Description: Existing reviews of research on voluntary childlessness generally take the form of narrative summaries, focusing on main topics investigated over time. In this chapter, the authors extend previous literature reviews to conduct a systematic review and content analysis of socio-historical and geopolitical aspects of knowledge production about voluntary childlessness. The dataset comprised 195 peer-reviewed articles that were coded and analysed to explore, inter alia: the main topic under investigation; country location of authors; sample characteristics; theoretical framework and methodology. The findings are discussed in relation to the socio-historical contexts of knowledge production, drawing on theoretical insights concerned with the politics of location, representation and research practice. The shifts in the topics of research from the 1970s, when substantial research first emerged, uphold the view of voluntary childlessness as non-normative. With some regional variation, knowledge is dominated by quantitative, hard science methodologies and mostly generated about privileged, married women living in the global North. The implications of this for future research concerned with reproductive freedom are outlined.
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- Date Issued: 2018
From universal to local: perspectives on cultural landscape heritage in South Africa
- Authors: Cocks, Michelle L , Vetter, Susan M , Wiersum, K Freerk
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141150 , vital:37948 , https://doi.org/10.1080/13527258.2017.1362573
- Description: The concept of cultural landscapes relates to the multifaceted links between people, place and identity. From a professional perspective, the concept refers to a category of designated conservation areas with specific biocultural heritage values. From a local perspective, it may refer to a landscape that is associated with the provision of a culturally-specific sense of identity and belonging. We explore these two perspectives through a comparative analysis of three cultural landscapes in South Africa, the ‘expert’ designated Mapungubwe Cultural Landscape and the Richtersveld Cultural and Botanical Landscape, and the local associative landscape of emaXhoseni, which is not formally recognised. We propose that a biocultural diversity perspective of heritage not only recognises the inextricable relationship between nature and culture, but it also gives prominence to the beliefs, values and practices of local people, and to strengthening their agency to safeguard their heritage in ways and forms that are relevant to them.
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- Date Issued: 2018
Funding higher education and training in South Africa: a comparative study of tax incentive measures, in conjunction with a dedicated tax
- Authors: Holm, Darryn
- Date: 2018
- Subjects: Education, Higher -- Finance , Education, Higher -- South Africa , Tax incentives -- Law and legislation -- South Africa , Student aid -- South Africa , Universities and Colleges -- Taxation -- Law and legislation -- South Africa , South Africa. Income Tax Act, 1962
- Language: English
- Type: text , Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/59445 , vital:27606
- Description: Higher education and training in South Africa in the post-Apartheid era has never been more volatile than it is currently, some two decades into democracy. Despite the many advances and achievements of higher education, the student protests of 2015 and 2016 have given expression to underlying fault-lines, including increasing student expectations and frustrations with regard to access and funding. This research was undertaken to document the underlying historical issues and models pertaining to funding within the higher education and training sector as well as the existing higher education and training taxation policies and incentives enacted in South Africa and selected international jurisdictions. This was done with a view to providing a framework for higher education and training tax policy formation in South Africa to assist in meeting its higher education and training “access and affordability” targets as set out in the National Plan on Higher Education and the Higher Education White Paper, while at the same time not hindering economic growth. A doctrinal research methodology was adopted in this study as it mainly analysed and interpreted legislation and policy documents and therefore the approach was qualitative in nature. An extensive literature survey was done in order to document the various internationally selected legislated higher education and training tax policies and incentives. The literature indicated that there are widespread funding perspectives and initiates, and that international tax policies enacted with the aim of ensuring that higher education and training is more accessible and affordable to the public, is stable and effective in certain jurisdictions. It is submitted that while a higher education dedicated tax may not be sufficiently effective in South Africa, a combination of broad-based tax incentives will help to promote the change to a more affordable and stable higher education funding system, whilst not preventing growth through sustainable development.
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- Date Issued: 2018
FyaMoneka: exploring the erasure of women within Zambian history
- Authors: Kalichini, Gladys
- Date: 2018
- Subjects: Women -- Zambia -- Historiography , Women -- Zambia -- History , Women -- Political activity -- Zambia , Women -- Zambia -- Social conditions , Collective memory -- Zambia , Death in art , Feminism -- Zambia , Male domination (Social structure) -- Zambia , Sex discrimination against women -- Zambia
- Language: English
- Type: text , Thesis , Masters , MFA
- Identifier: http://hdl.handle.net/10962/63186 , vital:28371
- Description: This Master of Fine Art submission, comprising of an exhibition and mini-thesis, explores the erasure of women’s narratives from Zambian history and collective memory. As a point of entry into the broader conversation of narratives of women marginalised in certain historicised events, this research analyses the narratives of Julia Chikamoneka and Alice Lenshina that are held in the collective memory of Zambian history. It focuses on the representations of narratives of women during and beyond colonial times, while hinging particularly on these two characters’ encounters with and against British rule in Northern Rhodesia (Zambia). Titled FyaMoneka: Exploring the Erasure of Women Within Zambian History, the mini-thesis examines the representations and positioning of women’s political activities within the liberation narrative that is recorded in the National Archives of Zambia (NAZ) and the United National Independence Party (UNIP) Archives. This mini-thesis highlights the fact that women have been written out of Zambia’s liberation narrative in the NAZ and the UNIP Archives, and remains mindful of the inherent modifications and erasures of women’s accounts over time, including the obfuscation or the absence of certain archival materials. This mini-thesis prospectively reconstructs Chikamoneka’s and Lenshina’s narratives using traces of their histories within collective memory through re/visiting processes of re-archivisation. The exhibition, titled ChaMoneka (It Has Become Visible): UnCasting Shadows, explores death and representations of death, where death is conceptualised as a metaphor for the erasure of women’s historical narratives, whereas the body represents the narrative. Based on an exploration of the relationship and tensions between collective memory and history, death within this exhibition is thematised as the course of fading away and a continuous process in which women’s narratives are erased.
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- Date Issued: 2018
Gaining cyber security insight through an analysis of open source intelligence data: an East African case study
- Authors: Chindipha, Stones Dalitso
- Date: 2018
- Subjects: Open source intelligence -- Africa, East , Computer security -- Africa, East , Computer networks -- Security measures -- Africa, East , Denial of service attacks -- Africa, East , Sentient Hvper-Optimised Data Access Network (SHODAN) , Internet Background Radiation (IBR)
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/60618 , vital:27805
- Description: With each passing year the number of Internet users and connected devices grows, and this is particularly so in Africa. This growth brings with it an increase in the prevalence cyber-attacks. Looking at the current state of affairs, cybersecurity incidents are more likely to increase in African countries mainly due to the increased prevalence and affordability of broadband connectivity which is coupled with lack of online security awareness. The adoption of mobile banking has aggravated the situation making the continent more attractive to hackers who bank on the malpractices of users. Using Open Source Intelligence (OSINT) data sources like Sentient Hvper-Optimised Data Access Network (SHODAN) and Internet Background Radiation (IBR), this research explores the prevalence of vulnerabilities and their accessibility to evber threat actors. The research focuses on the East African Community (EAC) comprising of Tanzania, Kenya, Malawi, and Uganda, An IBR data set collected by a Rhodes University network telescope spanning over 72 months was used in this research, along with two snapshot period of data from the SHODAN project. The findings shows that there is a significant risk to systems within the EAC, particularly using the SHODAN data. The MITRE CVSS threat scoring system was applied to this research using FREAK and Heartbleed as sample vulnerabilities identified in EAC, When looking at IBR, the research has shown that attackers can use either destination ports or IP source addresses to perform an attack which if not attended to may be reused yearly until later on move to the allocated IP address space once it starts making random probes. The moment it finds one vulnerable client on the network it spreads throughout like a worm, DDoS is one the attacks that can be generated from IBR, Since the SHODAN dataset had two collection points, the study has shown the changes that have occurred in Malawi and Tanzania for a period of 14 months by using three variables i.e, device type, operating systems, and ports. The research has also identified vulnerable devices in all the four countries. Apart from that, the study identified operating systems, products, OpenSSL, ports and ISPs as some of the variables that can be used to identify vulnerabilities in systems. In the ease of OpenSSL and products, this research went further by identifying the type of attack that can occur and its associated CVE-ID.
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- Date Issued: 2018
Gender and popular imaginaries in Africa:
- Authors: Spencer, Lynda G , Ligaga, Dina , Musila, Grace
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/138860 , vital:37679 , DOI: 10.1080/10130950.2018.1526467
- Description: If we accept that many Africans’ social perceptions on a range of questions, including gender, are shaped by popular cultural productions which retain a keen pulse on the everyday, then it is important to reflect on the interface between gender and popular imaginaries. The debate on the definition of the ‘popular’ remains an open one with multiple interpretations and categories. This contestation in itself gestures towards popular culture’s inclination for ambiguity and slipperiness. As Karin Barber (2018:13) reminds us, the popular constitutes “expressive forms that are constantly emergent, ephemeral, embedded in daily life, given to extraordinary bursts of activity and rapid transformation”. For George Ogola, popular cultural forms “engage with and subject the polity to constant critique through informal but widely recognised forms of censure” (2017:2). In this special issue, we use popular imaginaries to mean the range of cultural productions, platforms, and interactions between consumers and producers - which are often interchangeable - that capture the material, the affective, as inflected and refracted in different texts, contexts and platforms.
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- Date Issued: 2018
General features and kinetic analysis of thermoluminescence from annealed natural quartz
- Authors: Thomas, Sunil , Chithambo, Makaiko L
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/112885 , vital:33670 , https://doi.org/10.1016/j.jlumin.2018.02.003
- Description: The aim of this study is to explore the thermoluminescence properties of beta irradiated natural quartz annealed at 900 °C, that is, beyond its second phase inversion temperature of 867 °C. The sample was annealed to improve its sensitivity and to deplete any residual charge from electron traps. The glow-curve corresponding to 10 Gy shows three peaks when measured at 1 °C/s; a dominant one at 71 °C, the subject of this report, and two other ones at 125 and 177 °C. The dose response of the main peak was studied in the range 1–300 Gy. The activation energy of the main glow-peak was evaluated as ~1 eV. Kinetic analyses using various methods show that the main glow-peak follows first order kinetics.
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- Date Issued: 2018
Generalized linear models, with applications in fisheries research
- Authors: Sidumo, Bonelwa
- Date: 2018
- Subjects: Western mosquitofish , Analysis of variance , Fisheries Catch effort South Africa Sundays River (Eastern Cape) , Linear models (Statistics) , Multilevel models (Statistics) , Experimental design
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/61102 , vital:27975
- Description: Gambusia affinis (G. affinis) is an invasive fish species found in the Sundays River Valley of the Eastern Cape, South Africa, The relative abundance and population dynamics of G. affinis were quantified in five interconnected impoundments within the Sundays River Valley, This study utilised a G. affinis data set to demonstrate various, classical ANOVA models. Generalized linear models were used to standardize catch per unit effort (CPUE) estimates and to determine environmental variables which influenced the CPUE, Based on the generalized linear model results dam age, mean temperature, Oreochromis mossambicus abundance and Glossogobius callidus abundance had a significant effect on the G. affinis CPUE. The Albany Angling Association collected data during fishing tag and release events. These data were utilized to demonstrate repeated measures designs. Mixed-effects models provided a powerful and flexible tool for analyzing clustered data such as repeated measures data and nested data, lienee it has become tremendously popular as a framework for the analysis of bio-behavioral experiments. The results show that the mixed-effects methods proposed in this study are more efficient than those based on generalized linear models. These data were better modeled with mixed-effects models due to their flexibility in handling missing data.
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- Date Issued: 2018
Genetic analysis reveals harvested Lethrinus nebulosus in the Southwest Indian Ocean comprise two cryptic species
- Authors: Healey, Amy J E , Gouws, Gavin , Fennessy, Sean T , Kuguru, Baraka , Sauer, Warwick H H , Shaw, Paul W , McKeown, Niall J
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124538 , vital:35626 , https://doi.10.1093/icesjms/fsx245
- Description: This study initially aimed to investigate the genetic population/stock structuring of Lethrinus nebulosus in the Southwest Indian Ocean (SWIO) to inform management practices in light of emerging evidence of overharvesting of this species throughout its distribution. Adult samples were genotyped for 14 nuclear microsatellites and by sequencing fragments of the mtDNA control region and COI gene. A salient feature of the data was the congruent cyto-nuclear partitioning of samples into two high divergent, reciprocally monophyletic groups. This indicates that despite no a priori evidence, hitherto described L. nebulosus in the SWIO comprises two cryptic species that co-occur among southern samples. This intermingling indicates that, at least in southern samples, both species are being indiscriminately harvested, which may severely compromise sustainability. Limited microsatellite differentiation was detected within both species, though there was some evidence of isolation in the Mauritian population. In contrast, mtDNA revealed a pattern consistent with chaotic genetic patchiness, likely promoted by stochastic recruitment, which may necessitate a spatial bet-hedging approach to management to satisfy fishery management and conservation goals.
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- Date Issued: 2018
Genomic analysis reveals multiple mismatches between biological and management units in yellowfin tuna (Thunnus albacares)
- Authors: Mullins, Rachel B , McKeown, Niall J , Sauer, Warwick H H , Shaw, Paul W
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124549 , vital:35627 , https://doi.10.1093/icesjms/fsy102
- Description: The South African (SAF) yellowfin tuna (Thunnus albacares) fishery represents a potential example of misalignment between management units and biological processes. The SAF fishery spans an operational stock with a boundary at 20_E, either side of which fish are considered part of Atlantic or Indian Ocean regional stocks. However, the actual recruitment of fish from Atlantic and Indian Ocean spawning populations into SAF waters is unknown. To address this knowledge gap, genomic analysis (11 101 SNPs) was performed on samples from Atlantic and Indian Ocean spawning sites, including SAF sites spanning the current stock boundary. Outlier loci conferred high discriminatory power to assignment tests and revealed that all SAF fish were assigned to the Indian Ocean population and that no Atlantic Ocean fish appeared in the SAF samples. Additionally, several Indian Ocean migrants were detected at the Atlantic spawning site demonstrating asymmetric dispersal and the occurrence of a mixed-stock fishery in Atlantic waters. This study highlights both the spatial inaccuracy of current stock designations and a misunderstanding of interactions between the underlying biological units, which must be addressed in light of local and global declines of the species. Specifically, the entire SAF fishery must be managed as part of the Indian Ocean stock.
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- Date Issued: 2018
Geometry of deformed special relativity
- Authors: Sixaba, Vuyile
- Date: 2018
- Subjects: Special relativity (Physics) , Quantum gravity , Quantum theory , Geometry , Heisenberg uncertainty principle
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/59478 , vital:27615
- Description: We undertake a study of the classical regime in which Planck's constant and Newton's gravitational constant are negligible, but not their ratio, the Planck mass, in hopes that this could possibly lead to testable quantum gravity (QG) effects in a classical regime. In this quest for QG phenomenology we consider modifications of the standard dispersion relation of a free particle known as deformed special relativity (DSR). We try to geometrize DSR to find the geometric origin of the spacetime and momentum space. In particular, we adopt the framework of Hamilton geometry which is set up on phase space, as the cotangent bundle of configuration space in order to derive a purely phase space formulation of DSR. This is necessary when one wants to understand potential links of DSR with modifications of quantum mechanics such as Generalised Uncertainty Principles. It is subsequently observed that space-time and momentum space emerge naturally as curved and intertwined spaces. In conclusion we mention examples and applications of this framework as well as potential future developments.
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- Date Issued: 2018
Global trends of local ecological knowledge and future implications
- Authors: Aswani, Shankar , Lemahieu, Anne , Sauer, Warwick H H
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/70504 , vital:29668 , https://doi.org/10.1371/journal.pone.0195440
- Description: Local and indigenous knowledge is being transformed globally, particularly being eroded when pertaining to ecology. In many parts of the world, rural and indigenous communities are facing tremendous cultural, economic and environmental changes, which contribute to weaken their local knowledge base. In the face of profound and ongoing environmental changes, both cultural and biological diversity are likely to be severely impacted as well as local resilience capacities from this loss. In this global literature review, we analyse the drivers of various types of local and indigenous ecological knowledge transformation and assess the directionality of the reported change. Results of this analysis show a global impoverishment of local and indigenous knowledge with 77% of papers reporting the loss of knowledge driven by globalization, modernization, and market integration. The recording of this loss, however, is not symmetrical, with losses being recorded more strongly in medicinal and ethnobotanical knowledge. Persistence of knowledge (15% of the studies) occurred in studies where traditional practices were being maintained consiously and where hybrid knowledge was being produced as a resut of certain types of incentives created by economic development. This review provides some insights into local and indigenous ecological knowledge change, its causes and implications, and recommends venues for the development of replicable and comparative research. The larger implication of these results is that because of the interconnection between cultural and biological diversity, the loss of local and indigenous knowledge is likely to critically threaten effective conservation of biodiversity, particularly in community-based conservation local efforts.
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- Date Issued: 2018
Glycosylated zinc phthalocyanine-gold nanoparticle conjugates for photodynamic therapy
- Authors: Dube, Edith , Oluwole, David O , Nwaji, Njemuwa , Nyokong, Tebello
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/234524 , vital:50205 , xlink:href="https://doi.org/10.1016/j.saa.2018.05.081"
- Description: In this work, we report on the synthesis of tris-[(2,2,7,7-tetramethyltetrahydro-3aH-bis([1,3]dioxolo)[4,5-b:4′,5′-d]pyran-5-yl)methoxy)-2-(4-benzo[d]thiazol-2-ylphenoxyphthalocyaninato] zinc(II) (complex 3) and its linkage to gold nanoparticles (AuNPs) of different shapes through S-Au/N-Au self-assembly. The conjugates of complex 3 (with both gold nanorods (AuNR) and nanospheres (AuNS)), displayed decreased fluorescence quantum yield with corresponding improved triplet and singlet quantum yields compared to complex 3 alone, however 3-AuNR showed improved properties than 3-AuNS. Complex 3 showed relatively low in vitro dark cytotoxicity against the epithelial breast cancer cells with cell survival ≥ 85% at concentration ≤ 160 μg/mL but afforded reduced photodynamic therapy activity which may be due to aggregation. 3-AuNR afforded superior PDT activity with more than 50% viable cells at concentration ≥ 40 μg/mL in comparison to 3-AuNS with more than 50% viable cells at concentration ≥ 80 μg/mL. The superior activity of 3-AuNR is attributed to the photothermal therapy effect since nanorods absorb more light at 680 nm than nanospheres.
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- Date Issued: 2018
Going to university: the Influence of higher education on the lives of young South Africans
- Authors: Case, Jennifer M , Marshall, Delia , McKenna, Sioux , Mogashana, Disaapele
- Date: 2018
- Subjects: Education, Higher -- Aims and objectives -- South Africa Education, Higher -- South Africa College students -- South Africa Education, Higher -- South Africa -- Social aspects Education, Higher -- South Africa -- Economic aspects
- Language: English
- Type: e-book , text
- Identifier: http://hdl.handle.net/10962/61134 , vital:27981 , https://books.google.co.za/books?id=T-RMDwAAQBAJ&printsec=frontcover&source=gbs_ge_summary_r&cad=0#v=onepage&q&f=false
- Full Text: false
- Date Issued: 2018
Graphene quantum dots and their metallophthalocyanines nanoconjugates as novel photoluminescent nanosensors
- Authors: Achadu, Ojodomo John
- Date: 2018
- Subjects: Quantum dots , Graphene , Phthalocyanines , Nanoconjugates , Novel photoluminescent nanosensors , Metallophthalocyanines
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/60719 , vital:27821
- Description: The fabrication and application of graphene quantum dots (GQDs)-based photoluminescent probes for the detection of analytes is presented. GQDs were functionalized with complexes such as metallophthalocyanines (MPcs), metal nanoparticles (Au@Ag NPs), 2,2,6,6-tetramethyl(piperidin-1-yl)oxyl (TEMPO), maleimide and thymine for the sensing of target analytes such as ascorbic acid (AA), biothiols (cysteine, homocysteine and glutathione) and mercury ion (Hg²+). The design strategy and approach was based on the quenching of the fluorescence of the GQDs upon functionalization with the above-mentioned complexes, which could be restored in the presence of the target analytes (due to their specific interaction affinity with the complexes). For the detection of AA, GQDs were covalently and/or non-covalently conjugated to TEMPO-bearing complexes to form GQDs-4A-TEMPO and GQDs-TEMPO-MPc systems with nanomolar limits of detection. For the detection of biothiols, Au@Ag NPs and maleimide-bearing complexes (MPc), which have specific affinity to interact with biothiols, were deployed. Hg²+ detection involved the use of GQDs and/or MPcs with thiol and thymine groups, respectively. In addition, a smart sensing platform was designed for the dual detection of biothiols and Hg²+ using supramolecular hybrid of polyethyleneimine functionalized-GQDs and MPc-Au@Ag conjugate. The probe could detect, in a sequential manner, Hg²+ and biothiols with high sensitivity. Results obtained from the LODs of the probes showed that GQDs sensing performances could be enhanced in the presence of MPcs. The probes designed in this work were successfully deployed in the assays of the target analytes in real samples and the recoveries obtained confirmed the analytical applicability of the probes.
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- Date Issued: 2018
Graphite: origin, deposits and economics : an exploration study of the Orom Graphite project
- Authors: Van den Berg, Jacobus Petrus
- Date: 2018
- Subjects: Graphite , Ore deposits , Geophysics , Graphite mines and mining Economic aspects Africa, East , Trenches , Project management
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/63786 , vital:28489
- Description: Developing exploration projects successfully requires that the Reasonable Prospects for Eventual Economic Extraction (RPEEE) be confirmed and based on the global market perception and trend. The exploration methods applied in the attempt to establish this RPEEE must be based on a key management framework that assures the results, and eventually the conclusion, are obtained with best practical and technical approaches whilst managing the risks and capitalizing on each result. The Orom Graphite project is located within the East African Orogenic belt, a suture zone between the Congo craton and the SLAMIN shield, formed during the formation of Gondwana during the late Proterozoic to early-Phanerozoic era. The closing of the Mozambique ocean, and the eventual collision between the craton and shield, occurred along the paleo-earths equator and migrated towards lower latitudes. This, along with the period’s biodiversity boom, provided the perfect deposition environment for carbonaceous sediments which were later metamorphosed to amphibolite and granulites grade metamorphism, resulting in the carbonization and the eventual graphitization of these carbonaceous sediments. The project is located within a poorly developed part of Uganda with the closest port situated some 1 500 km to the east in Kenya. The poorly developed infrastructure along with probable high logistical cost assigns a low competitivity index if compared to the economic costs of peer projects. However, the potential resources of the Orom Graphite project suggest that the Life of Mine (LOM) can rival the largest resource currently reported within the market. The current market conditions suggest that a possible oversupply of graphite concentrate will dominate the market within the next 4 to 10 years. This suggests that new graphite projects such as the Orom Graphite project are likely to develop into the production phase once the global supply and demand stabilize. This requires the Orom Graphite project to develop from its current scoping study level to a project development study level associated with a definitive feasibility study. To date, the project developed through mapping, reconnaissance drilling, geophysical survey and trenching programs increasing the Net Present Value (NPV) considerably based upon a Cost-Based Valuation approach using Prospectivity Enhancement Multiplier (PEM). The metallurgical studies could however not produce a graphite concentrate product within industrial grade standards. The risk associated with developing the project further into the Mineral Resource Estimation (MRE) phase was quantified and risk was evaluated by implementing a point decision tree and calculating the Expected Monetary Value (EMV). Due to the unfavourable metallurgical results obtained to date, the risk associated with undertaking an additional metallurgical test is considerable with a slight chance of producing a negative project value estimated at 65%. JP van den Berg Rhodes University Overall, the Orom Graphite project contains favourable geological formations with a potential large resource. Market trends indicate that a considerable resource is currently being developed and can supply the global market for the next 4 to 10 years. The project’s location within a landlocked country decreases its economic competitiveness with peer project and the unfavourable, but not conclusive, metallurgical results obtained during the scoping phase do not instil confidence that the project will develop into a productive mine soon. Managing the project development with future graphite demand in mind is the key to determining whether the project still has future value.
- Full Text:
- Date Issued: 2018
Green skills Transformative niches for greening work
- Authors: Ramsarup, Preesha , Rosenberg, Eureta , Lotz-Sisitka, Heila , Jenkin, Nicola
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/436882 , vital:73313 , ISBN 978-981-15-6370-6 , https://doi.org/10.1007/978-981-15-6370-6_8
- Description: Supporting green skills development is integral in the transition to a green economy. Green skills can be difficult to define and measure at an aggregate level because they are a socially constructed concept, intangible and are often unobservable. Further, a demand-led approach to green skills has not worked because employers are unable to effectively articulate their needs to skills delivery bodies. This advances the need for a transformative methodology that is able to provide a more nu-anced view of skills planning to support green work. Drawing on transition theorists, this chapter demonstrates that greening work transitions occur in “niches” at local levels, where nexus concerns arise around the impetus to green work. Furthermore, it is from these transformative niches that wider social changes and regime shifts are driven or emerge. Using experiences from the chemicals sector in South Africa, the chapter illus-trates the need to develop non-reductionist conceptualisations that illustrate the “regime lock-ins” as well as green skills oppor-tunities at multiple levels.
- Full Text:
- Date Issued: 2018