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Fluorescence behavior of nanoconjugates of graphene quantum dots and zinc phthalocyanines

  • Authors: Achadu, Ojodomo John , Uddin, Imran , Nyokong, Tebello
  • Date: 2016
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/188777 , vital:44784 , xlink:href="https://doi.org/10.1016/j.jphotochem.2015.11.006"
  • Description: Graphene quantum dots (GQDs) and zinc phthalocyanines interactions in different modes (covalent and non-covalent) are reported in this study. GQDs were covalently attached to the following complexes: zinc tetraamino phthalocyanine (ZnTAPc) via amide coupling, zinc tetracarboxyphenoxy Pc (ZnTCPPc) (π–π interaction) and cationic zinc tetrapyridiloxy Pc (ZnTmPyPc) (ionic interaction). GQDs fluorescence was quenched in the presence of the ZnPc derivatives. The nanoensembles of GQDs–ZnPcs showed stimulated emissions of the ZnPcs. The suggested quenching mechanism is through Förster resonance energy transfer (FRET). These novel nanoensembles hold promise for various optical and luminescence based applications.
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  • Date Issued: 2016

Fluorescence properties of alloyed ZnSeS quantum dots overcoated with ZnTe and ZnTe/ZnS shells

  • Authors: Adegoke, Oluwasesan , Mashazi, Philani N , Nyokong, Tebello , Forbes, Patricia B C
  • Date: 2016
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/240754 , vital:50868 , xlink:href="https://doi.org/10.1016/j.optmat.2016.02.024"
  • Description: Fluorescent alloyed ternary ZnSeS quantum dots (QDs) have been synthesized via the pyrolysis of organometallic precursors. The effects of passivation of ZnTe and ZnTe/ZnS shells on the optical properties of the ternary alloyed ZnSeS core have been studied. A ligand exchange reaction using L-cysteine as a capping ligand was used to obtain water-soluble nanocrystals. The nanocrystals were each characterized by UV/vis absorption and fluorescence spectroscopy, transmission electron microscopy, X-ray diffractometry (XRD) and X-ray photoelectron spectroscopy (XPS). The photoluminescence (PL) quantum yield (QY) of alloyed ZnSeS QDs was 14% and this value increased to 27% when ZnTe was overcoated around the surface but further coating with a ZnS shell decreased the PL QY slightly to 24%. This implies that ZnTe shell suppressed non-radiative recombination exciton states in the alloyed core while further layering with a ZnS shell offered no further improvement in suppressing the defect states. XPS analysis confirmed the presence of the first shell layering but showed a weakened intensity signal of S (2p) and Se (3d) for the ZnSeS/ZnTe/ZnS QDs. Our work demonstrates for the first time that shell passivation of alloyed Zn-based QDs can offer improved optical properties. We hope the optical information presented in this work will be useful in the selection of alloyed Zn-based QDs appropriate for the intended application.
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  • Date Issued: 2016

Focus on 'the family'?: how South African family policy could fail us

  • Authors: Morison, Tracy , Lynch, Ingrid , Macleod, Catriona I
  • Date: 2016
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/446244 , vital:74484 , xlink:href="https://hsrc.ac.za/uploads/pageContent/7505/HSRC%20POLICY%20BRIEF%2011%20-%20MORISON%20Family%20policy_PRESS%20(2).pdf"
  • Description: In the past decade South African policymakers have increasingly focused on families as sites of state intervention. To date, several family policies have been developed to support societal well-being and cohesion. The most recent policy document is the White Paper on Families in South Africa (DSD 2012), which aims to facilitate the mainstreaming of a family perspective into all government policy-making. Family policies are intended to provide support, enhance family members’ wellbeing, strengthen family relationships, and help families address social challenges, such as economic instability. Their ultimate aim is to ensure a safe and socially cohesive society (Robila 2014). A core concern, therefore, is with promoting ‘stable, healthy families’. This concern is valid in South Africa since many families experienced a profound lack of stability under apartheid and today instability is brought about by various socio-economic changes, especially the HIV and AIDS epidemic.
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  • Date Issued: 2016

Food waste generation and potential interventions at Rhodes University, South Africa

  • Authors: Painter, Kathleen , Thondhlana, Gladman , Kua, Harn W
  • Date: 2016
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/67733 , vital:29135 , https://doi.org/10.1016/j.wasman.2016.07.013
  • Description: Publisher version , Estimation of food waste generation represents the first step when considering efforts to reduce waste generation and monitor food waste reduction against set targets. This study reports on an estimation of food waste generated in university dining halls at Rhodes University, South Africa. Daily food waste generation was estimated at about 555 g per student or 2 tonnes across all sample dining halls, translating to about 450 tonnes per year. The results show that food waste is influenced by an array of contextual factors, including distance to dining hall, gender composition of hall and meal times and meal options. It is estimated that the university could save up to US$ 80 000 annually for every 10% reduction in the current rate of food waste generation. Possible educational, technical and administrative interventions for food waste reduction are discussed.
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  • Date Issued: 2016

Foraging ecology of the gentoo penguin, pygoscelis papua, at Marion Island

  • Authors: Carpenter-Kling, Tegan
  • Date: 2016
  • Subjects: Gentoo penguin -- Food
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10948/4912 , vital:20766
  • Description: The distribution and subsequent availability of marine predators’ prey is highly variable and is linked to fluctuating oceanographic parameters. It is well documented that annual breeding success of seabirds is related to the temporal availability of prey. Knowledge of a seabird’s diet and at sea distribution is therefore critical in deducing the effect of a fluctuating environment on a seabirds’ population and, furthermore, to understand seabirds role in the environment. The gentoo penguin population at sub-Antarctic Marion Island experienced a decline of 52% between 1994 and 2012. It has been speculated that long term changes in the local marine environment, due to a southward shift of the sub-Antarctic Front (SAF), and subsequent changes in prey availability is the ultimate causal factor. Therefore, this thesis investigates the temporal variation in the diet these birds over three years, through the use of stomach content samples. It then investigates whether the composition of the diet has changed over the long term (approximately 18 years). Additionally, the at sea distribution of these birds was investigated using temperature-depth recorders (TDRs) and global positioning system (GPS) devices. This study represents the first to investigate variation in the diet over three years and over the long term. It is also the first study to track these birds fine scale movement. Over three years, the diet exhibited a high degree of variability. The birds primarily foraged on the fish, Lepidonotothen larseni and the crustaceans, Nauticaris marionis and Euphausia vallentiniy. Over three years, L. larseni became increasingly more important during the breeding season. This was attributed to an increase in availability of these fish during this time, as this time corresponded to the transition of these fish from the larval pelagic phase to the benthic adult phase. Furthermore, the proportions of N. marionis and E. vallentini in the diet varied significantly among years. This variation is possibly a result of the highly variable latitudinal position of the SAF. The diet changed over the long term. There was significantly less N. marionis and more E. vallentini in the diet during more recent years. The long term southward shift of the SAF is considered to be a leading cause of these significant changes in the diet. The shallow inter-island shelf between Marion and Prince Edward Island was an important foraging area possibly due to predictable prey resources. In addition, these birds exhibited an important and possibly unique foraging strategy. They performed short self-maintenance trips where after they return to land to roost for the night. The following day these trips were followed by a longer foraging trip that was followed by chick provisioning. This strategy is unique among seabirds longer trips are associated with self-maintenance and not chick provisioning. This study has provided important knowledge of the foraging ecology of the gentoo penguin at sub-Antarctic Marion Island. It highlights the necessity for continuation of diet and tracking studies of these birds if we are to fully understand the ultimate factors that are causing the decline in their breeding success and population numbers.
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  • Date Issued: 2016

Formulation development and thermorheological properties of crumb rubber/eva modified bitumen

  • Authors: Nare, Keith Dumisani
  • Date: 2016
  • Subjects: Crumb rubber Bitumen , Vinyl acetate
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10948/11974 , vital:27015
  • Description: The study deals with the formulation development and thermorheological properties of crumb rubber/ethylene vinyl acetate (EVA) modified bitumen with the aim of optimizing the amount of crumb rubber and EVA loadings in bitumen based on thermorheological parameters complex shear modulus, phase angle and rutting parameter. In the modified binders EVA offers plastomer properties whereas the crumb rubber confers elasticity to the bitumen. 13.75% crumb rubber and 2.5% EVA loadings based on aging indices gave the best optimized mixture. The thermorheological behaviour of the best optimized mixture was compared to industrial grade EVA (AP-1) and crumb rubber (AR-1) modified bitumen. Improving aging behaviour of the bitumen was evaluated using four antioxidants: carbon black, hydrated lime, Irganox 1010 and Irgafos 168. The least aging indices at 58˚C and 64˚C were obtained from a 1:1:1 Irganox 1010/hydrated lime/carbon black mixture. SARA (saturates, aromatics, resins and asphaltene) analysis gave the chemical background for application of antioxidants to reduce the propensity of short term aging. To further improve the EVA/crumb rubber optimized mixture for workability FT wax (Sasobit®) was assayed at loadings from 0-2.5%. This was done to match the EVA content and maintain the original maximum loading of 2.5% in the optimized mixture. The phase change abilities of FT wax owing to the high latent heat enabled co-crystallization with the EVA with the elastomeric backbone of crumb rubber acting as support material. The energy-sustainability nexus was found to have worked at less than 1% loading of FT wax in the EVA/crumb rubber modified bitumen. Response surface methodology approach to all the sections of work was used to come up with the optimized mixtures based on rheological parameters complex shear modulus, phase angle and rutting parameter at test temperature 64˚C. The interaction chemistry of bitumen, crumb rubber, EVA and FT wax was found to be first and second order in all cases involving individual contributions and co-interaction amongst the factors. Project costing for each section of work (optimizing section, antioxidant section and FT wax section) was conducted involving the raw materials used, equipment used, labour involved and other costs incurred for all the project work.
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  • Date Issued: 2016

Formulation of an optimal non-targeted liposome preparation for fusion with tumour cell line membranes

  • Authors: Motala, Ismail Mohammed , Roux, Saartjie
  • Date: 2016
  • Subjects: Liposomes Cancer -- Adjuvant treatment Nanotechnology -- Cancer
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10948/12220 , vital:27045
  • Description: The most common treatment used for cancer is chemotherapy. Chemotherapeutic agents have a greater affinity for rapidly dividing cells which is a characteristic of tumour cells. Although anti-cancer agents have their advantages in providing anti-cancer effects, they can be seen as highly toxic molecules posing a threat to normal healthy tissue within the human body. However, these toxic therapies need to be delivered to tumour sites without damaging healthy tissue. Liposomes can serve as a delivery system for these toxic molecules and be delivered to the tumour site via the EPR effect. Hence, liposomes that fuse with tumour cell line membranes are advantageous in delivering payloads of drugs directly into the tumour cell without damaging normal healthy tissue. The aim of the study was to formulate an optimised liposome preparation in order to enhance cellular uptake by MCF-7, Caco-2 and C3A cancer cell lines via membrane fusion. The optimal liposome formulation was aimed to be prepared utilising a statistical design approach in order to determine the ranges of the parameters that were furthermost optimal in formulating an ideal liposome preparation. The primary screening design was conducted using a 24-1 fractional factorial design that took into account the four parameters that were used to determine the optimisation of the liposomal preparation. The four variables used in the liposome preparation were the phospholipid type (PS or DOPE), the concentration of cholesteryl hemisuccinate (CHEMS) (10 – 40 %), the concentration of PEG2000-PE (0.5 – 4 %) and liposome size (100 or 200 nm). Liposomes were prepared using thin film hydration method and characterisation for size and zeta potential was carried out using photon correlation spectroscopy (PCS). Visual characterisation of liposome size was carried out using atomic force microscopy (AFM). Liposomes were exposed the cancer cell lines with visualisation and uptake being measured using fluorescent microscopy and flow cytometry, respectively. An optimal liposome preparation was prepared following the statistical design method. The optimal liposome preparation consisted of phospholipid type PS, 22.91 % of CHEMS, 4 % of PEG2000-PE and a liposome size of 200 nm. AFM analysis has shown that optimal liposome sizes ranged between 130 and 170 nm. Flow cytometry analysis indicated high level of liposome uptake with actual values falling below the predicted values set out by the statistical design. Fluorescence microscopy captured images of the fluorescent liposomes concentrated on the membrane of cells. The objective of the study was to determine from literature which variables would be desirable in preparing an optimal non-targeted liposome preparation. This was achieved by identifying four such variables and utilising them in a statistical design approach which was screened in order to determine the ideal parameters in preparing the optimised liposome batch. Therefore, from the results obtained it can be concluded that the aim of the study were met by preparing an optimal liposome preparation that has the ability to fuse with the tumour cell line membranes.
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  • Date Issued: 2016

Foundation Phase male student-teachers’ experiences during Teaching Practice: Implications for Initial Teacher Training

  • Authors: Makeleni, Sive
  • Date: 2016
  • Subjects: Student teaching -- South Africa Teachers -- Training of -- South Africa Teaching -- South Africa
  • Language: English
  • Type: Thesis , Masters , Degree
  • Identifier: http://hdl.handle.net/10353/5171 , vital:29095
  • Description: The aim of this study was to explore experiences of Foundation Phase male studentteachers during teaching practice. Four Bachelor of Education Foundation Phase male student-teachers were selected for the purpose of this study. Venturing of males in Foundation Phase specialisation is phenomenon. Foundation Phase has been viewed as a female territory for many years. As a result, there are few males teaching in FP. The study employed the qualitative approach as a suitable approach. As the study sought to explore experiences, a phenomenological design was followed. In a true phenomenological design, unstructured interviews and personal diaries are used for data collection. In this study data were collected through unstructured interviews and personal diaries of the participants. I employed interpretivism as a research paradigm. The study found that despite South Africa being a democratic country Foundation Phase is still viewed as a female space. Findings reveal that male student-teachers feel that in a democratic country, gender equality should be exercised. The study revealed that teaching profession is undermined. As much as participants reported about insecurities, they also reported about the benefits of being a male studentteacher in Foundation Phase specialisation. One of the benefits reported is knowledge and understanding of child development theories. The participants reported that during TP, they were seen as role-models, as father figures and resources. The research recommends that Initial Teacher Education Programme should do more in preparing male student-teachers venturing in Foundation Phase. The research also suggests that all stakeholders involved in education should have a programme focusing on developing teaching profession to be a prestigious profession. The government and all education stakeholders should also focus on gender equality within FP specialisation, both in Initial Teacher Education institutions and in schools.
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  • Date Issued: 2016

Foundation phase male student-teacher’s experiences during teaching practice: implications for initial teacher training

  • Authors: Makeleni, Sive
  • Date: 2016
  • Subjects: Student teaching -- South Africa Teachers -- Training of -- South Africa Teaching -- South Africa
  • Language: English
  • Type: Thesis , Masters , Degree
  • Identifier: http://hdl.handle.net/10353/4780 , vital:28519
  • Description: The aim of this study was to explore experiences of Foundation Phase male student teachers during teaching practice. Four Bachelor of Education Foundation Phase male student-teachers were selected for the purpose of this study. Venturing of males in Foundation Phase specialisation is phenomenon. Foundation Phase has been viewed as a female territory for many years. As a result, there are few males teaching in FP. The study employed the qualitative approach as a suitable approach. As the study sought to explore experiences, a phenomenological design was followed. In a true phenomenological design, unstructured interviews and personal diaries are used for data collection. In this study data were collected through unstructured interviews and personal diaries of the participants. I employed interpretivism as a research paradigm.
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  • Date Issued: 2016

Four husbands for Ma Lindi: an exploration of the interaction between theatrical performance, gender, and sexuality in a South African urban context

  • Authors: Vaughan, Clara
  • Date: 2016
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/4610 , vital:20700
  • Description: The thesis investigates the possibilities and limitations of theatre-making in providing a space for young people to collectively create, share, and interrogate understandings about sex, sexuality and gender. I use as a case study a theatremaking process I facilitated with a group of first year drama students at the Market Theatre Laboratory, in which we created a play called Four Husbands for Ma Lindi. The research analyses how this process interacted with the identities-in-becoming of the individual creators, and their engagement with the world, through a methodology that views them as experts on their own lives. There are three main arguments that I put forward in this thesis: the first is based on the experiences of healing, increased confidence and self-knowledge described by the participants as a result of sharing their personal stories in making the play. I argue that exploring autobiographical narratives through the aesthetic of theatre creates a group story that re-situates the narratives, the tellers and the witnesses in ways that can be productive for sexual and personal wellbeing, while also providing a counter-narrative that problematises the idea that sharing personal stories is always and necessarily a positive act. My second argument is that theatre-making, because it is an embodied performance pedagogy, is a constructive site in which to interrogate, deconstruct and subvert embedded gender norms and values, which are learnt and reiterated in the body. My third argument considers the relationship between theatre and change that is suggested by the findings of the research. In an analysis of the responses of the participants, I contend that theatre's potential for creating change in the socio-cultural domain lies in its ability to carve out spaces for improvisation, rather than to serve as a rehearsal for the real world. This is the position from which I then consider my ethics of practice and the role and responsibility of the facilitator in processes that view theatre-making as a critical performance pedagogy.
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  • Date Issued: 2016

FRAME: frame routing and manipulation engine

  • Authors: Pennefather, Sean Niel
  • Date: 2016
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/3608 , vital:20529
  • Description: This research reports on the design and implementation of FRAME: an embedded hardware network processing platform designed to perform network frame manipulation and monitoring. This is possible at line speeds compliant with the IEEE 802.3 Ethernet standard. The system provides frame manipulation functionality to aid in the development and implementation of network testing environments. Platform cost and ease of use are both considered during design resulting in fabrication of hardware and the development of Link, a Domain Specific Language used to create custom applications that are compatible with the platform. Functionality of the resulting platform is shown through conformance testing of designed modules and application examples. Throughput testing showed that the peak throughput achievable by the platform is limited to 86.4 Mbit/s, comparable to commodity 100 Mbit hardware and the total cost of the prototype platform ranged between $220 and $254.
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  • Date Issued: 2016

From global to regional and back again: common climate stressors of marine ecosystems relevant for adaptation across five ocean warming hotspots

  • Authors: Popova, Ekaterina , Yool, Andrew , Byfield, Valborg , Cochrane, Kevern , Coward, Andrew C , Salim, Shyam S , Gasalla, Maria A , Henson, S.A , Hobday, Alistair J , Pecl, Gretta T , Sauer, Warwick H H , Roberts, Michael J
  • Date: 2016
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/124514 , vital:35623 , https://doi.10.1111/gcb.13247
  • Description: Ocean warming ‘hotspots’ are regions characterized by above-average temperature increases over recent years, for which there are significant consequences for both living marine resources and the societies that depend on them. As such, they represent early warning systems for understanding the impacts of marine climate change, and test-beds for developing adaptation options for coping with those impacts. Here, we examine five hotspots off the coasts of eastern Australia, South Africa, Madagascar, India and Brazil. These particular hotspots have underpinned a large international partnership that is working towards improving community adaptation by characterizing, assessing and projecting the likely future of coastal-marine food resources through the provision and sharing of knowledge. To inform this effort, we employ a high-resolution global ocean model forced by Representative Concentration Pathway 8.5 and simulated to year 2099. In addition to the sea surface temperature, we analyse projected stratification, nutrient supply, primary production, anthropogenic CO2-driven ocean acidification, deoxygenation and ocean circulation. Our simulation finds that the temperature-defined hotspots studied here will continue to experience warming but, with the exception of eastern Australia, may not remain the fastest warming ocean areas over the next century as the strongest warming is projected to occur in the subpolar and polar areas of the Northern Hemisphere. Additionally, we find that recent rapid change in SST is not necessarily an indicator that these areas are also hotspots of the other climatic stressors examined. However, a consistent facet of the hotspots studied here is that they are all strongly influenced by ocean circulation, which has already shown changes in the recent past and is projected to undergo further strong change into the future. In addition to the fast warming, change in local ocean circulation represents a distinct feature of present and future climate change impacting marine ecosystems in these areas.
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  • Date Issued: 2016

Fundisa for Change teacher professional development programme

  • Authors: Tshiningayamwe, Sirkka A
  • Date: 2016
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/432999 , vital:72922 , xlink:href="https://eeasa.org.za/wp-content/uploads/2017/05/EEASA-Bullitin-vol-43.pdf"
  • Description: Environment and sustainability content has been integrated into the South African curricula documents, including the past ones. This integration was followed by initiatives which aimed at supporting teachers to implement environmental knowledge and action in the curriculum. For example, the Learning for Sustainability project was piloted in Gauteng and Mpumalanga province between the year 1997 and 2000. The project followed a three pillar approach of integrating environmental education in the curriculum: teacher development, curriculum development and materials development. As part of the project, a spiral model approach to teacher professional development was introduced.
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  • Date Issued: 2016

Fusing fact and fiction: biography and autobiography in the novels of Virginia Woolf

  • Authors: White, Joshua Craig
  • Date: 2016
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/4005 , vital:20580
  • Description: Virginia Woolf was noted for a preoccupation with the genre of life-writing throughout her career. Her aims when it came to reshaping the nature of biographical and autobiographical literature were numerous. She veered away from the aggrandising and patriarchal methods with which Victorian biographers tended to depict their subjects. She increased the focus on women in life-writing, examining and subverting traditionally prescribed gender roles prevalent in both her society and the literature that reflected it, and advocating a balance between male and female patterns of thinking. She also devised a method of incorporating both basic biographical fact and aspects of fiction into life-writing in order to approach a more truthful depiction of a subject’s personality or character. This method is linked to the aforementioned balance of gendered thought patterns, since Woolf often aligns factuality with male thinking and the contrasting qualities of fiction, such as intuition, ambivalence and perspicacity, with female thinking. This thesis examines three novels which demonstrate Woolf’s constant preoccupation with combining fact and fiction in order to capture the essence of personality. In her debut novel, The Voyage Out, she presents Rachel Vinrace, who must achieve a balance of male-oriented fact with female-oriented insight in order to fashion a sufficient identity for herself and to identify others in a selective and judicious manner, thus being simultaneously autobiographical and biographical. In Orlando, Woolf explicitly subverts the traditional Victorian biography by depicting Vita Sackville-West as a man who transforms into a woman and remains living for over 400 years. In presenting such a character, Woolf posits that personality consists of and is influenced by myriad aspects of a person’s life that cannot be documented in the restrictive manner employed by Victorian biographers. Orlando’s essence being obfuscated by manifold “selves” attests to Woolf problematizing attempts to attain such an essence. The same challenge is particularly important in her autobiographical novel, To the Lighthouse, in which she transposes the traumas of her own life into a fictitious narrative in order to achieve catharsis for her and her readers, and to present the difficulty in capturing the essence of character. The conclusion that Woolf eventually posits is that personality cannot be reduced to an essence, but rather that it consists of idiosyncrasies that are various, intertwining, and capricious.
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  • Date Issued: 2016

Gender equality in the provision and utilisation of women administrative personnel : a comparative study of the Camdeboo Local Municipality and Inxuba Yethemba Local Municipality

  • Authors: Dywili, Mhlobo Douglas
  • Date: 2016
  • Subjects: Women -- Government policy -- South Africa -- Eastern Cape Sex discrimination against women -- South Africa -- Eastern Cape Women's rights -- South Africa -- Eastern Cape , Equality -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Doctoral , DPhil
  • Identifier: http://hdl.handle.net/10353/2414 , vital:27817
  • Description: In 2000, cabinet adopted the South African Policy framework for women’s empowerment and gender equality, 2000 (Policy framework) which provided for the establishment of the National Gender Machinery (NGM). The NGM is a network of coordinated structures within and outside government which operate cooperatively in facilitating political, social, economic and other forms of transformation to dismantle systemic gender inequality and promote equality between women and men. The implementation of gender equality policy as a function area has constitutionally been given to the national and provincial legislatures in South Africa. The constitution allocated this function to the local sphere of government. Camdeboo and Inxuba Yethemba local municipal authorities are the facilitators of sustainable gender equality policies to citizens on behalf of the national and provincial spheres of government. The study was thus conducted within the Camdeboo local municipality and Inxuba Yethemba local municipality. Camdeboo locoal municipality is one of nine local municipalities in Sarah Baartman district municipality. Inxuba Yethemba local municipality is in Chris Hani district municipality. The purpose of the study was to evaluate the implementation of gender equality in the Provision and Utilisation of Women administration Personnel a comparative study of the Camdeboo local municipality and the Inxuba Yethemba local municipality and to determine the impact of the existing policy on the gender equality policy on the needs of women of both municipalities. For this purpose the fundamental and overall study problem was found to be that the gender equality at the Camdeboo and Inxuba Yethemba is hampered by the implementation of an inadequate municipality gender equality policy and by incompetent municipal personnel in particular and in general by the municipality itself. These action do not satisfy the main purpose of the Employment Equity Act no 55 of 1998 to achieve in the workplace by promoting equal opportunity and fair treatment in all forms of employment through elimination of unfair discrimination as well as the implementation of affirmative action measures. The hypothesis was furthermore based on the fact that the existing gender policy of Camdeboo local municipality and Inxuba Yethemba local municipality gender equality policy are inadequate to satisfy women and impacts negatively if not harmfully on human being of women. The study revealed that besides the implementation of gender equality policy by these incompetent municipal personnel, there are economic, social, political and physical effects on women. In case of applications for senior management position, preference is always given to their male counterparts at the expense of equally qualified female applications. Secondly, Gender equality in human resource determination forms part of the processing phase in the system theory. These two municipalities should be made to commit themselves by appending their signatures to all control measures put in place to evaluate the level and the extent of gender equality across all the departments/ sections in the municipality. Any section/ department that implements gender equality more effectively should be identified applauded and given recognition. This would motivate and eliminate gender inequality. Personnel provision and utilization is of paramount importance to every organization. It then becomes extremely necessary to examine the gender equality on human resource determination.
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  • Date Issued: 2016

Gender possibilities in the African context as explored by Mariama Ba's So long a letter, Neshani Andrea's The purple violet of Oshaantu and Sindiwe Magona's Beauty gift

  • Authors: Goremusandu, Tania
  • Date: 2016
  • Subjects: Women and literature Feminist fiction -- History and criticism Women authors, African
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10353/6469 , vital:29739
  • Description: Gender oppression has been a significant discussion to the development of gender, cultural and feminist theories. The primary focus of this study is to investigate how patriarchal traditions, colonialism, and religious oppression force women to struggle under constrictions oppositional to empowerment. Thus, the project provides a comparative analysis of three texts from different African postcolonial societies by three African female writers: Mariama Bâ, Neshani Andreas and Sindiwe Magona. The author‟s biographies and historical context of their novels will be analyzed, as well as a summary of their stories will be included in order to provide the context for gender criticism. These writer‟s work; So Long a Letter, The Purple Violet of Oshaantu and Beauty‟s Gift depict patriarchal, cultural and religious laws which exist in Senegal, Namibia and South Africa, respectively, that limit the position of women. Therefore, this study will interrogate the experience of African women as inscribed in these selected texts, uncovering the literary expressions of gender oppression as well as the possibilities of empowerment. The selected texts will be analyzed through the lens of Gender studies, African feminism and Cultural studies. From these theories, the focus of the study is on the struggles of the female characters living in patriarchal societies as well as on the idea that gender is constructed socially and culturally in the African context. In conclusion, the emergence of these renowned female African writers together with the emancipation of African countries from colonial supremacy has opened a space for women to compensate and correct the stereotyped female images in African literature and post- colonial societies. Most contemporary African writers like Buchi Emecheta, Tsitsi Dangarembga, Sindiwe Magona, Mariama Bâ and Neshani Andreas have shown that women are seeking to attain empowerment. As a result, this study can be viewed as an opportunity to highlight such experiences by continuing to interrogate the writings of African women writers and to explore their gender-based themes so as to inform and or inspire the implementation of women empowerment. It will broaden and encourage further academic discussion in the field of Cultural studies and gender criticism of women‟s literature within the African context.
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  • Date Issued: 2016

Generation of New Ecotoxicity Data for Salts Using Indigenous South African Freshwater Macroinvertebrate: Updating the National Salts Toxicity Database

  • Authors: Mensah, Paul K , Mgaba, Ntombekhaya , Griffin, Neil J , Odume, Oghenekaro N , Palmer, Carolyn G
  • Date: 2016
  • Subjects: To be catalogued
  • Language: English
  • Type: text , report
  • Identifier: http://hdl.handle.net/10962/437854 , vital:73417 , ISBN 978-1-4312-0747-3 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/KV%20353.pdf
  • Description: Scherman and Palmer (2013) reviewed the historical and current trends of Environmental Water Quality (EWQ) in South Africa. Based on the review, they identified research gaps for which they proposed a co-ordinated set of projects that need to be commissioned and executed to fill these gaps. These co-ordinated set of projects include update of TEACHA (Tool for Ecological Aquatic Chemical Habitat Assessment); update of the national salt toxicity database; integration of Resource Directed Measures (RDM) components (ie Ecological Reserve, Re-source Quality Objectives (RQOs) and Classification); integrating water quality and quantity; evaluation of the RDM participatory process based on research and current understandings of complex social-ecological systems and ecosystem services; and integrating RDM and SDC (Source Direct Control) to ensure coherent link between the two. The overarching aim of the above set of projects is to support implementa-tion of the National Water Resource Strategy 2 (NWRS2). Therefore, the main objective of this project to contribute to addressing the second research gap listed above (ie updating the national salt toxicity data-base). Noting that the database contains only data on single salts with nothing on salt mixtures, the project also generated binary salt mixtures data for the database, in addition to generating data for single salts.
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  • Date Issued: 2016

Genetic and biological characterisation of a novel South African Cydia pomonella granulovirus (CpGV-SA) isolate

  • Authors: Motsoeneng, Boitumelo Madika
  • Date: 2016
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:20503 , http://hdl.handle.net/10962/d1021266
  • Description: The codling moth, Cydia pomonella (L.) (Lepidoptera: Tortricidae), is the primary pest of pome fruit cultivated worldwide. The control of this insect pest has been dependent on the frequent use of broad-spectrum chemical pesticides, which has led to the development of resistance in pest populations and negative effects on human health and the environment. The Betabaculovirus of C. pomonella has successfully been applied as a biological control agent in integrated pest management (IPM) programmes for the suppression of pest populations worldwide. Previously, all Cydia pomonella granulovirus (CpGV) biopesticides were based on a Mexican isolate (CpGV-M) and although these products are highly efficient at controlling C. pomonella, resistance cases have been reported across Europe. The identification of novel CpGV isolates as additional or alternative control agents to manage resistance is therefore necessary. This study aimed to genetically and biologically characterise a novel South African C. pomonella granulovirus isolate and to test its virulence against neonate larvae. Based on the morphology of the occlusion bodies observed using transmission electron microscopy, granuloviruses were recovered from diseased and dead larvae collected from an orchard in South Africa where no virus applications had been made. DNA was extracted and the identification of the isolated granulovirus was achieved through the PCR amplification and sequencing of the lef-8, lef-9, granulin and egt genes. Submission of the gene sequences to BLAST revealed high percentage identities to sequences from various CpGV isolates, resulting in the naming of the isolate in this study as the South African Cydia pomonella granulovirus (CpGV-SA) isolate. Phylogenetic analysis based on the single nucleotide polymorphisms (SNPs) detected in the lef-8, lef-9 and granulin nucleotide sequences grouped the South African isolate with CpGV-E2 (genome type B) and CpGV-S (genome type E). The CpGV-SA isolate was further genetically characterised by restriction endonuclease analysis and complete sequencing of the genomic DNA. Differences were observed for the BamHI, EcoRI, PstI and XhoI profiles of CpGV-SA in comparison to the respective profiles generated for CpGV-M extracted from a biopesticide, Carpovirusine® (Arysta Lifescience, France). Several genetic variations between the complete genome sequence of CpGV-SA and the reference isolate, CpGV-M1, as well as a recent genome submission of CpGV-M, both representing genome type A were observed. The complete genome analysis confirmed that CpGV-SA is genetically different from the Mexican CpGV isolate, used in thedevelopment of most biopesticides. In silico restriction profiles of the genome sequence obtained for CpGV-SA and genome sequences of genetically different CpGV isolates originating from Mexico (M1 and M), England (E2), Canada (S) and Iran (I12 and I07), available on the NCBI’s GenBank database confirmed that CpGV-SA is of mixed genotypes. Furthermore, the South African isolate shared the single common difference found in the pe38 gene of resistance overcoming isolates, which was the absence of an internal 24 nucleotide repeat present in CpGV-M1. In addition to the common difference, SNPs detected in the pe38 gene grouped the isolate with the CpGV-S isolate, suggesting that the CpGV-SA isolate is predominantly of genome type E. To determine the biological activity of CpGV-SA against neonate C. pomonella larvae, surface bioassays were conducted alongside CpGV-M (Carpovirusine®) bioassays. The LC50 and LC90 values for the South African isolate were 1.6 × 103 and 1.2 × 105 OBs/ml respectively. The LT50 was determined to be 135 hours. These values were similar to the values obtained for CpGV-M (Carpovirusine®). The results in this study suggest that a novel South African CpGV isolate of mixed genotypes, potentially able to overcome resistance in C. pomonella, with biological activity similar to CpGV-M (Carpovirusine®) and important for the control of C. pomonella was recovered. The CpGV-SA isolate could therefore potentially be developed into a biopesticide for use in resistance management strategies against C. pomonella populations in South Africa.
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  • Date Issued: 2016

Genetic structure and biogeography of three wrasse species (Labridae) within the Western Indian Ocean

  • Authors: Mayekiso, Sisanda
  • Date: 2016
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/1114 , vital:20021
  • Description: The biogeography of wrasses within the Western Indian Ocean (WIO) is poorly understood, with regard to origins and genetic differentiation or connectivity among the regions of the WIO. This region is a good model for studying the influence of physical complexities and biogeographic breaks in shaping patterns of differentiation in wrasses. Three reef-associated fish species, Cheilio inermis, Thalassoma hebraicum and T. lunare, were selected to examine the factors that have influenced patterns of differentiation across the WIO. Each species was sampled from various localities of the WIO, the Red Sea and Indo-West Pacific Islands. Sequence data were generated from two mitochondrial gene fragments (cytochrome b and ATPase 6) and one nuclear locus (the first intron of the ribosomal protein S7 gene). Genetic analyses were used to calculate genetic diversity indices within species, which were then compared among species. The relationships among haplotypes and alleles were constructed using median-joining networks. Where necessary, neighbour-joining trees (NJ) were constructed to examine relationships among haplotypes and alleles for the Thalassoma species. Population structure was analysed using AMOVA and pairwise ФST to compare and calculate differentiation between the WIO localities. Mismatch distributions were used to examine population growth and decline or stability, and demographic parameters were used to calculate time of population expansion. There was high haplotype (h = 0.88 to 0.98) and low nucleotide diversities (π = 0.003 to 0.008) among all species for mitochondrial markers. For S7 intron I, high allelic (A = 0.95 to 0.98) and low nucleotide diversities (π = 0.002 to 0.014) were observed for all species. The pairwise ФST values revealed little to great (ФST = -0.02 to 0.67) genetic differentiation between localities, across all species for the three gene regions. The pairwise comparisons indicated the differentiation in C. inermis of Tanzania and Kenya from Mozambique and Nosy Be (Madagascar). The widespread C. inermis also revealed the differentiation of Kenya and Tanzania. For C. inermis, the AMOVAs of ATPase 6 and cytochrome b data indicated high differentiation among defined locality groups. The groups were defined according to geographic proximity. However, the AMOVA of the nuclear gene (S7 intron I) did not find variation among defined locality groups. Cheilio inermis revealed a sequence divergence of 0.4%. The divergence that was found in C. inermis was not enough to suggest a cryptic species within the WIO. Overall, the widespread and monotypic C. inermis revealed genetic differentiation within the WIO. Thalassoma hebraicum generally revealed little genetic differentiation across the WIO. The AMOVAs of the three gene regions showed no variation among specimens of the defined locality groups. However, some differentiation was found between localities. The pairwise comparisons of T. hebraicum revealed the differentiation of Seychelles from the African mainland and Madagascar. Southern Africa was observed to be differentiated from Nosy Be and Zanzibar. The observed differentiation could be caused by oceanic barriers such as the South Equatorial Current (SEQC), East African Coastal Current (EACC), and the Comoros Gyres and eddies in the Mozambique Channel, and Agulhas Current. Thalassoma lunare revealed genetic isolation between the WIO and the Red Sea as well as within the WIO. The genetic isolation between the WIO and the Red Sea is probably due to the historical isolation by the Bab al Mandab and contemporary barriers such as the cold upwelling cells in Somalia. The differentiation of Maldives from the African mainland and Seychelles could be due to distance and the upwelling cells created by monsoon winds. Mismatch distributions suggested that C. inermis and T. hebraicum had undergone demographic expansion during the Pleistocene (92 678 to 40 219 years ago). The results of the current study are similar to those from previous studies of WIO reef fish species, and the results of the present study could have potential implications for conservation and fisheries management. Single genetic markers and single species studies do not detect all barriers to dispersal in the WIO, thus they are insufficient to inform conservation management. Thus, the use of multispecies and genetic markers in the current study can be adopted by other studies of the marine taxa of the WIO.
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  • Date Issued: 2016

Genetics, physiology, proteomics of quality protein maize inbred lines under drought and heat stress

  • Authors: Pfunde, Cleopatra Nyaradzo
  • Date: 2016
  • Subjects: Corn Drought-tolerant plants Proteomics
  • Language: English
  • Type: Thesis , Masters/Doctoral , Crop Science
  • Identifier: http://hdl.handle.net/10353/11696 , vital:39098
  • Description: When plants perceive heat stress alone or in combination with drought, they activate several responses to synchronize development and molecular activities to ensure survival. In this study, a multidiscipline approach was adopted to investigate the plant genetics, proteomics and physiology for understanding the mechanisms underlying the adaptive response to combined drought and heat stress. The quality protein maize (QPM) inbred lines used had varied degrees of tolerance to both heat stress alone and in combination with drought. The overall objective of this study was to identify drought and heat tolerant germplasm that combine well under drought and heat stress for use in breeding programs to develop new QPM varieties. Initially, the genetic diversity among available inbred lines was estimated using two molecular markers, simple sequence repeats (SSRs) and single nucleotide polymorphisms (SNPs). The results indicated that moderate diversity exists among the QPM inbred lines which can be exploited to generate high performing hybrids. Cross combinations between QS26 and CIM2 and those between QS6 and CIM14 were selected as crosses likely to give substantial heterosis in the field because of the high genetic distances that were found between them using SNPs. Screening of inbred lines for drought and heat tolerance was done at the early germination and seedling stages. Differences in heat tolerance at both stages of growth were observed. Heat tolerant inbred lines at early germination stage had longer coleoptiles and radicles after recovery. The following inbred lines exhibited acquired thermo-tolerance, QS6, CIM7, QS17 and QS19, while CIM12, QS1, CIM21 and QS32 showed basal thermo-tolerance. At the early seedling stage inbred lines with significant differences (P< 0.001) in morpho-physiological traits were noted under heat stress alone and under combined drought and heat stress. However, no significant differences were noted for morpho-physiological measurements in the control treatment. Electron transport rate, sub-stomatal CO2, and stomatal conductance were significantly (P<0.001) reduced in response to combined drought and heat stress. Thus, drought coupled with heat stress resulted in stomatal closure, decreased photosynthetic rate, enhanced respiration and increased leaf temperature for susceptible inbred lines. The combined effects of drought and heat stress were more deleterious than the individual effect of heat stress alone as indicated by the reduction in dry weight. Based on the physiological parameters, biomass and tolerance indices, inbred lines QS22, CIM18 and QS6 showed tolerance to combined drought and heat stress, while CIM18, QS14 and QS30 exhibited thermo-tolerance. Inbred line CIM18 showed cross tolerance to combined drought and heat stress, and to heat stress alone. Further investigations into the comparative proteomic analysis of CIM18 (tolerant) with QS21 (susceptible) under combined drought and heat stress at seedling stage revealed that photosynthetic and stress related proteins were upregulated in CIM18. In addition, the abundance of heat shock proteins such as HSP70 and sHSP 17.8 kDa meant that CIM18 was better able to maintain cellular homeostasis and metabolism. The presence of metabolism related proteins meant that the energy needs of photosynthesis and other activities were met under drought and heat stress. Anti-oxidant enzymes such as glutathione s transferase were responsible for detoxification of reactive oxygen species induced by oxidative stress. These proteins mediated tolerance to combined stress in CIM18. The proteins that were micro-sequenced have previously been identified in individual drought and heat stress studies. The expression of these proteins under combined stress indicated that mechanisms from both stresses were pooled to confer tolerance in CIM18. Accordingly, the study proposes that CIM18 is a drought and heat tolerant QPM inbred line and is recommended for inclusion in breeding programs aimed at the development of drought and heat tolerant varieties. QPM has the potential to improve human nutrition in several rural households. The combining ability analysis of inbred lines revealed that GCA effects under combined drought and heat stress were significant for ears per plant, chlorophyll content, canopy temperature, anthesis silking interval, days to 50percent silking and ear length. Specific combining ability effects were significant for grain yield, days to 50percent anthesis, chlorophyll content and senescence. The study revealed that non-additive gene action was more important in determining grain yield under combined drought and heat stress. Inbred lines L2, L3, L7 and L3, L7 and L11 were good sources of genes for high grain yield under well-watered and combined drought and heat stress respectively. Cross combinations L3 x L13 (3.05 t/ha) and L5 x L9 (2.95 t/ha) were the best performing single cross hybrids for grain yield while cross combination L2 x L10 (1.33t/ha) was the least performing hybrid under combined stress conditions. Under well-watered conditions, the highest yielding crosses were between L2 x L13 (6.51t/ha) and L2 x L8 (6.46 t/ha). The inbred lines identified as sources of drought and heat tolerance and the high yielding cross combinations maybe useful for improving tolerance by generating hybrids or synthetic QPM maize varieties. The inbred lines which exhibited tolerance to both drought and heat stress were genetically diverse and were able to maintain photosynthesis and hence growth during stressful conditions. The ability of these genotypes to accumulate biomass or produce yield under stressful conditions highlights underlying mechanisms which need to be further exploited. While partial proteomic work was done in this study, a more comprehensive study looking into greater depth at the genes responsible for these mechanisms is paramount to fully utilize and/or transfer these genes to other desirable genotypes.
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  • Date Issued: 2016
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