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An in-silico investigation of Morita-Baylis-Hillman accessible heterocyclic analogues for applications as novel HIV-1 C protease inhibitors

  • Authors: Sigauke, Lester Takunda
  • Date: 2015
  • Subjects: Protease inhibitors , Heterocyclic compounds , HIV (Viruses) , HIV infections , Drug resistance , Cheminformatics
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4152 , http://hdl.handle.net/10962/d1017913
  • Description: Cheminformatic approaches have been employed to optimize the bis-coumarin scaffold identified by Onywera et al. (2012) as a potential hit against the protease HIV-1 protein. The Open Babel library of commands was used to access functions that were incorporated into a markov chain recursive program that generated 17750 analogues of the bis-coumarin scaffold. The Morita-Baylis-Hillman accessible heterocycles were used to introduce structural diversity within the virtual library. In silico high through-put virtual screening using AutoDock Vina was used to rapidly screen the virtual library ligand set against 61 protease models built by Onywera et al. (2012). CheS-Mapper computed a principle component analysis of the compounds based on 13 selected chemical descriptors. The compounds were plotted against the principle component analysis within a 3 dimensional chemical space in order to inspect the diversity of the virtual library. The physicochemical properties and binding affinities were used to identify the top 3 performing ligands. ACPYPE was used to inspect the constitutional properties and eliminated virtual compounds that possessed open valences. Chromene based ligand 805 and ligand 6610 were selected as the lead candidates from the high-throughput virtual screening procedure we employed. Molecular dynamic simulations of the lead candidates performed for 5 ns allowed the stability of the ligand protein complexes with protease model 305152. The free energy of binding of the leads with protease model 305152 was computed over the first 50 ps of simulation using the molecular mechanics Poisson-Boltzmann method. Analysis structural features and energy profiles from molecular dynamic simulations of the protein–ligand complexes indicated that although ligand 805 had a weaker binding affinity in terms of docking, it outperformed ligand 6610 in terms of complex stability and free energy of binding. Medicinal chemistry approaches will be used to optimize the lead candidates before their analogues will be synthesized and assayed for in vivo protease activity.
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  • Date Issued: 2015

An indirectly controlled high-speed servo valve using piezo actuators

  • Authors: Behre, Leander
  • Date: 2015
  • Subjects: Piezoelectric materials Piezoelectric devices -- Materials , Internal combustion engines Mechatronics Automation
  • Language: English
  • Type: Thesis , Masters , MEng
  • Identifier: http://hdl.handle.net/10948/50099 , vital:42040
  • Description: Since the exhaust emissions legislation for motor vehicles with combustion engines is complicating the manufacturing of environmental yet powerful engines more than ever, automobile manufacturers have approached this challenge by means of downsizing, hybridization of combustion and electric engines and variable valve opening times. In these cases conventional, mechanical valve trains are still used. The subject of this master thesis is the development of a mechatronic control unit as replacement for the camshaft driven valve train of common combustion engines. The system’s aim is a contribution to the progression of the development of modern combustion engines satisfying current demands in terms of economy and efficiency. The developed system is based on the “Full Variable Valve Train” project, founded at the “Institute of Vehicle Construction Wolfsburg” at the “Ostfalia University of Applied Sciences”. An indirectly controlled high speed servo valve that is actuated by a piezoelectric actuator and pressurized hydraulic fluid is being developed. The overall aim is to obtain advantages from a control engineering perspective, being able to reduce the size of the used piezo actuator and hence solve the packaging and regulation issues of the overall system. After manufacturing and improvement activities, a system could be developed that allows a variable control of the engine valve movement. The best results are achieved using a rectangular function for the engine valve actuator. The system allows engine valve operation independent from the crankshaft position and shows the potential to generate higher engine torque and power output while decreasing fuel consumption and emissions at the same time.
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  • Date Issued: 2015

An interevention strategy for improving reading comprehension in grade 9: a case study in one secondary school in East london education district

  • Authors: Fesi, Liziwe
  • Date: 2015
  • Subjects: English language -- Study and teaching -- South Africa -- Eastern Cape Reading comprehension -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , Degree
  • Identifier: http://hdl.handle.net/10353/5905 , vital:29417
  • Description: The study focused on strategies for improving reading comprehension skills at Grade 9 level through story writing in one secondary school in the East London Education District. Vygotskian theory formed the theoretical framework for this study, aligned with language theories as relevant literature for this particular research study. Data was generated from 15 Grade 9 learners who were selected from 3 Grade 9 classes using convenience sampling, comprising of five learners from Grade 9(a) intervention group, five learners from Grade 9(b) and five learners from Grade 9(c) non-intervention group who were selected for this study with the inclusion of two Grade 9 teachers and one Grade 8 teacher. Involvement of the grade 8 teacher is relevant to determine the voice from a Grade 8 teacher as an informed voice, which filtered into understanding how and why Grade 9 learners are unable to read and write with understanding in their present grade. The teachers were given three questions for semi-structured interviews. All the learners were given a specific activity as a pre-assessment without intervention strategy. The Grade 9(a), which is the intervention class, used story writing as an intervention strategy where they began a two week study using intensive intervention strategies, amounting to a total of 18 weeks study from pre-assessment to post-assessment. At the conclusion of the study the selected learners undertook a post-assessment using the same specific activity as in the pre-assessment. Subsequently, these selected Grade 9 learners’ reading comprehension pre-assessment and post-assessment was analysed. Five of the grade 9(a) learners demonstrated significant improvement in the intervention activities they were given. Grade 9(b) and Grade 9(c) showed difficulty in the post-assessment as they were the non-intervention group. It was concluded that Grade 9(a) learners performed better in the post-assessment. This could be attributed to the use of story writing as an intervention strategy to improve their English reading and reading comprehension skills. Keywords: intervention, reading, comprehension.
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  • Date Issued: 2015

An international study on the influence of intrinsic rewards on the intrinsic motivation, work engagement and retention of employees in non-profit organisations

  • Authors: Renard, Michelle
  • Date: 2015
  • Subjects: Employee motivation , Achievement motivation , Organisational behaviour
  • Language: English
  • Type: Thesis , Doctoral , DPhil
  • Identifier: http://hdl.handle.net/10948/5148 , vital:20815
  • Description: The primary objective of this thesis was to investigate whether intrinsic rewards play a role in the intrinsic motivation, work engagement and retention of employees working within non-profit organisations in Australia, Belgium, South Africa and the United States of America. It therefore served to form a cross-cultural comparison between employees from these four geographically dispersed yet culturally similar countries. A further aim was to determine whether demographic differences occurred across the four constructs studied. In order to achieve these objectives, a theoretical model was constructed to highlight the relationships between the constructs under study. The study made use of both qualitative and quantitative research to achieve the above-mentioned objectives. As a result of the data obtained from 15 qualitative interviews conducted with non-profit employees in Belgium and South Africa, two measuring instruments, namely the Intrinsic Work Rewards Scale and the Intrinsic Work Motivation Scale, were developed to assess intrinsic rewards and intrinsic motivation respectively. These measuring instruments were qualitatively piloted on a sample of academics and non-profit employees, and were translated from English into Dutch for use on the Belgian sample. Once these instruments had been refined, they were combined with instruments to measure work engagement and intention to quit to form a composite questionnaire. This questionnaire was completed electronically by 587 non-profit employees from the four countries under study. Data analysis was conducted in the form of descriptive and inferential statistics, including frequency tables, Cronbach’s alpha testing, exploratory and confirmatory factor analysis, Pearson’s Product Moment Correlations, chi-square tests, t-tests, analysis of variance and structural equation modelling. The quantitative findings showed that intrinsic rewards lead to higher levels of intrinsic motivation, which in turn causes higher levels of work engagement and lower levels of intention to quit. Intrinsic rewards were also found directly to predict a reduction in employees’ intentions to quit their non-profit organisations, and work engagement directly predicted an increase in intention to quit. From a cross-cultural perspective, practically significant inter-country differences were discovered across the intrinsic rewards of meaningful work and challenging work; across intrinsic motivation and its three dimensions (personal connection to one’s work, personal desire to make a difference, and personal desire to perform); and across work engagement and its three factors (absorption, dedication and vigour). In addition to these inter-country results, age and job level differences were discovered across the four constructs under study, together with significant correlations between the four constructs. The Intrinsic Work Rewards Scale and the Intrinsic Work Motivation Scale were successfully validated in both English and Dutch in this study, with a number of forms of validity being confirmed through factor analyses and correlations. Reliability was proven through satisfactory Cronbach’s alpha values being obtained for both language versions of the instruments. These results theoretically contribute to literature pertaining to intrinsic rewards and intrinsic motivation as a result of the development of two measuring instruments that were empirically validated to assess these constructs. Furthermore, the results make a valuable contribution to the field of rewards management globally. This study’s findings provide evidence for causal relationships between four constructs not previously tested empirically, specifically within Australia, Belgium, South Africa and the United States of America. Consequently, this study’s results hold important implications for the management of non-profit employees worldwide.
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  • Date Issued: 2015

An interrogation of the representation of the San and Tonga ethnic ‘minorities’ in the Zimbabwean state-owned Chronicle, and the privately owned Newsday Southern Edition/Southern Eye newspapers during 2013

  • Authors: Mlotshwa, Khanyile Joseph
  • Date: 2015
  • Subjects: The Chronicle (Zimbabwe) , Newsday Southern Edition/Southern Eye (Zimbabwe) , Mass media and ethnic relations -- Zimbabwe , Mass media -- Political aspects -- Zimbabwe , Mass media and nationalism -- Zimbabwe , Minorities and journalism -- Zimbabwe , Press and politics -- Zimbabwe , San (African people) -- Social conditions , Tonga (Zambezi people) -- Social conditions , Critical discourse analysis
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:3549 , http://hdl.handle.net/10962/d1018546
  • Description: This study critically interrogates representations of the San and Tonga in the Chronicle and the NewsDay Southern Edition/Southern Eye newspapers in 2013. It makes sense of how these representations and the journalistic practices that underwrite them position the ethnic groups as ‘minorities’ - in relation to other ethnic groups - within the discourses of Zimbabwean nationalism. Underpinned by a constructionist approach (Hall, 1997), the study makes sense of the San and Tonga identities otherwise silenced by the “bi-modal” (Ndlovu- Gatsheni, 2012: 536; Masunungure, 2006) Shona/Ndebele approach to Zimbabwean nationalism. In socio-historic terms, the study is located within the re-emergence of ‘ethnicity’ to contest Zimbabwean nationalism(s) during debates for the New Constitution leading to a Referendum in March 2013. The thesis draws on social theories that offer explanatory power in studying media representations, which include postcolonial (Bhabha, 1990, 1994; Spivak, 1995), hegemony (Gramsci, 1971), and discourse (Foucault, 1970, 1972; Laclau and Mouffe, 1985) theories. These theories speak to the ways in which discourses about identity, belonging, citizenship and democracy are constructed in situations in which unequal social power is contested. The thesis links journalism practice with the politics of representation drawing on normative theories of journalism (Christians et al, 2009), the professional ideology of journalism (Tuchman, 1972; Golding and Elliot, 1996; Hall et al., 1996), and the concept of journalists as an ‘interpretive community’ (Zelizer, 1993). These theories allow us to unmask the role of journalism’s social power in representation, and map ways in which the agency of the journalists has to be considered in relation to the structural features of the media industry in particular, and society in general. The study is qualitative and proceeds by way of combining a Critical Discourse Analysis (CDA) (Fairclough, 1992; Richardson, 2007) and ideological analysis (Thompson, 1990) of eight news texts taken from the two newspapers and in-depth interviews with 13 journalists from the two newspapers. This way we account for the media representations journalists produced: sometimes reproducing stereotypes, at other times, resisting them. Journalists not only regard themselves as belonging to the dominant ethnic groups of Shona or Ndebele, but as part of the middle class; they take Zimbabwean nationalism for granted, reproducing it as common-sense through sourcing patterns dominated by elites. This silences the San and Tonga constructing them as a ‘minority’ through a double play of invisibility and hyper visibility, where they either don’t appear in the news texts or are overly stereotyped.
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  • Date Issued: 2015

An investigation into an afterschool intervention programme aimed at improving learners' mental computation skills

  • Authors: Moyo, Kwethemba Michael
  • Date: 2015
  • Subjects: After-school programs -- Namibia , Mental arithmetic , Mental arithmetic -- Study and teaching (Secondary) , Mental arithmetic -- Study and teaching (Secondary) -- Activity programs , Mathematical ability
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:2041 , http://hdl.handle.net/10962/d1017352
  • Description: This case study centres round an afterschool intervention programme aimed at enhancing mental computation skills of Grade 8 learners at a secondary school in the Erongo educational region of Namibia. Nine research participants took part in the study, and the mental computational strategies exhibited by these participants constitutes the unit of analysis. The study is anchored within an interpretive paradigm and is theoretically underpinned by constructivist epistemology. Kilpatrick, Swafford and Findell’s (2001) model of mathematical proficiency provides the conceptual framework supporting the study. The research was carried out in four sequential phases – an initial pre-test, the intervention itself, a follow-up post-test, and a focus group discussion. The study highlights the underdevelopment of mental computation skills and the associated lack of appropriate mental computational strategies in secondary school learners. It is recommended that appropriate time within the school curriculum be allocated for the development of learners’ mental computation skills.
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  • Date Issued: 2015

An investigation into English second language competence and performance of Shona and Ndebele first lanuage learners

  • Authors: Nhongo, Raphael
  • Date: 2015
  • Subjects: Applied linguistics -- South Africa , Language and languages -- Study and teaching -- South Africa , Multilingual education -- South Africa
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10353/12216 , vital:39198
  • Description: The thrust of the study was to investigate the common ESL practices towards proficiency amongst O‟ level learners who are L1 speakers of either Shona or Ndebele and who are from either a rural or an urban setting. The aim of the study was to scrutinize how a learner‟s first language and the rural and urban environment influence ESL proficiency. The aim was to establish how rural and urban settings condition ESL proficiency and how ESL proficiency differs between these two settings. The other aim of the study was to establish the strategies that are used by teachers and learners in ESL teaching and learning and also to evaluate the effectiveness of such strategies. The study was qualitative in nature although a limited quantitative design was employed in the presentation of frequency tables. The study used a case study design. The information that was used in this study was gathered through the use of proficiency tests that were administered to forty O‟ level learners and through content analysis of learners‟ essays which were extracted from their essay exercise books. Sixteen O‟ level English language teachers, six English language examiners, one subject manager of English language and two curriculum developers were interviewed. The secondary data also played an important role in the study. The results of the study showed that teachers and learners use a number of strategies in the teaching and learning of ESL of which some of the strategies that they use have previously not been documented by other L2 researchers. It was also realized that learners in rural areas are at a disadvantage as compared to those in rural schools and such challenges include lack of exposure, inadequate reading materials, faulty instruction, unavailability of libraries and some other social issues. The major conclusion that was made in this study was that ESL learning and teaching strategies are of crucial importance to competence and performance in ESL proficiency.
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  • Date Issued: 2015

An investigation into how Grade 11 Biology teachers mediate learning through code-switching from English to Oshiwambo : a case study

  • Authors: Kanime, Justina Kashuupulwa
  • Date: 2015
  • Subjects: Biology -- Study and teaching (Secondary) -- Namibia -- Omusati , English language -- Namibia -- Omusati , Ndonga language -- Namibia -- Omusati , Code switching (Linguistics) -- Namibia -- Omusati , Pedagogical content knowledge , Native language and education -- Namibia -- Omusati
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:2034 , http://hdl.handle.net/10962/d1017345
  • Description: This study aimed to investigate how Grade 11 Biology teachers mediate learning through code-switching from English to Oshiwambo. It was triggered by my experience as a teacher when I came to observe that the majority of teachers still use the home language during their lessons though the language policy for schools in Namibia clearly states that English should be used as a medium of instruction from Grade Four onwards. The research was carried out at Happy Secondary School (pseudonym), a rural government school in Omusati Region, Namibia. It was a qualitative case study underpinned by an interpretive paradigm. The unit of analysis was the mediation of learning through codeswitching from English to Oshiwambo. Document analysis, questionnaires, interviews (semistructured, focus group, stimulated recall interviews) and lesson observations were used as data gathering techniques, to ensure adequate coverage, validity and trustworthiness of the data gathered. The study adopted Vygotsky’s social constructivism and the socio-cultural perspective in conjunction with Shulman’s Pedagogical Content Knowledge (PCK) as the theoretical frameworks. The data analysis process entailed organising data into themes from which four analytical statements were then derived in relation to the research questions. The study found that both Biology teachers and learners view code-switching as a useful tool in making learners understand the biological concepts. The study revealed that Biology teachers code-switch from English to Oshiwambo to make learners understand better, increase participation, explain concepts, elaborate, for disciplinary purposes, when giving examples of everyday knowledge events and when asking questions. The study also revealed that learners code-switch mainly for good communication, easier self-expression, due to loss of words, when unprepared to explain concepts and due to fear of making mistakes. It emerged, however, that both teachers and learners experience some challenges when codeswitching from English to Oshiwambo is used to mediate learning in Biology lessons. These include time constraints, lack of biological terms in Oshiwambo, different Oshiwambo dialects and the language policy. In addition, learners also lose the opportunity to learn English and find it difficult to answer questions in the examinations. The study revealed that Biology teachers and learners try to overcome these challenges by good lesson preparation, mini-teaching, using English/Oshindonga dictionaries or simply by adhering to the language policy.
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  • Date Issued: 2015

An investigation into how Grade 11 Physical Science teachers mediate learning of the topic stoichiometry : a case study

  • Authors: Kanime, Mwene Kashiiwandapo
  • Date: 2015
  • Subjects: Science -- Study and teaching (Secondary) -- Namibia -- Oshikoto , Stoichiometry -- Study and teaching (Secondary) -- Namibia -- Oshikoto , Pedagogical content knowledge , Learning -- Namibia -- Oshikoto , Teacher effectiveness -- Namibia -- Oshikoto
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:2035 , http://hdl.handle.net/10962/d1017346
  • Description: Stoichiometry is proven to be one of the difficult topics for learners in the NSSC Physical Science syllabus due to its abstract nature. Over the years the Examiner’s reports reveal that learners' performance is very poor in this topic. In addition, learners fear the topic and have developed a negative attitude toward it. It is against this background that I decided to carry out a qualitative case study; investigating how teachers mediate the learning of stoichiometry. The study was conducted at two schools in the Oshikoto Region, Namibia and it involved two grade 11 Physical Science teachers. The study is located within the interpretive paradigm and made use of interviews, document analysis and lesson observations (which were video-taped and transcribed) followed by stimulated recall interviews to generate data. The generated data were analyzed using the inductive approach whereby themes were identified. The themes were later used to develop analytical statements in relation to my research questions and these were used to interpret the data. Moreover, the study adopted the notion of pedagogical content knowledge (PCK) proposed by Shulman (1986, 1987) as well as Vygotsky's (1978) mediation of learning and social constructivism as the theoretical frameworks. The data were validated by triangulation, member checking as well as using the stimulated recall interviews while watching the videos with each participant. The findings of the study show that teachers use several tools to mediate the learning process and this includes the use of language, learners' prior knowledge and analogies. In addition, it emerged in this study that teachers are faced with a number of challenges when mediating learning of this topic. Hence, the study recommends that teachers should develop their pedagogical content knowledge for them to effectively eliminate the challenges faced as well as to come up with the best teaching strategies which they can use to mediate learning and help learners make sense of the topic stoichiometry.
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  • Date Issued: 2015

An investigation into how Grade 7 Natural Science teachers mediate learning through code-switching from English to Silozi in the Zambezi region of Namibia : a case study

  • Authors: Denuga, Hildred Malilo
  • Date: 2015
  • Subjects: Science -- Study and teaching (Elementary) -- Namibia -- Case studies , Code switching (Linguistics) , Language and education
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:2026 , http://hdl.handle.net/10962/d1017337
  • Description: The Namibian government’s language policy for schools has opted for English as the official language of education. But the use of English in Namibian schools has nevertheless presented certain challenges. Although the Ministry of Education has chosen English as the language of instruction from upper primary (Grade 4) up to the tertiary level, it has been found that English proficiency is poor among both learners and teachers. It is against this backdrop that this study sought to investigate how Grade 7 Natural Science teachers mediate learning through code-switching from English to Silozi in the Zambezi Region of Namibia. The study explored Natural Science teachers’ perceptions and experiences of code-switching, how they and their learners make sense of concepts in science classes when code-switching is applied, and lastly, how code-switching from English to Silozi enables or constrains learning in Natural Science classes. The main question is: How do Grade 7 Natural Science teachers mediate learning through code-switching from English to Silozi? A qualitative case study underpinned by an interpretive paradigm was carried out at Zebra School (pseudonym) in the Zambezi Region of Namibia with two participant teachers. My unit of analysis was mediation of learning through code-switching, and data were obtained from lesson observations, questionnaires, interviews and document analysis. A variety of data gathering technique was employed for triangulation purposes to enhance the validity and trustworthiness of the data. During the data analysis process, data were grouped into common themes and subsequently organized into analytical statements in relation to the research questions. It was found that code-switching was widely employed in Grade 7 Natural Science classes in the Zambezi Region. It was also found that teachers code-switch to help learners understand the subject content, to explain concepts, to emphasize points and to include learners’ participation in the subject. The findings also revealed that some few teachers were against code-switching because examinations are written in English and the language policy does not recommend code-switching. Notwithstanding this, since the majority of teachers do code-switch to support their learners’ understanding in science classes, I recommend that education curriculum planners should include code-switching in the curriculum guidelines, and that the practice should be officially acknowledged as a legitimate strategy for teachers.
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  • Date Issued: 2015

An investigation into how grade 9 girls participate during practical work in Physical Science lessons : a case study

  • Authors: Munyanyo, Johanna
  • Date: 2015
  • Subjects: Physical sciences -- Study and teaching (Secondary) -- Namibia , Teenage girls -- Education , Sex differences in education -- Namibia , Sex discrimination in education -- Namibia , Physical sciences -- Study and teaching (Secondary) -- Sex differences
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:2042 , http://hdl.handle.net/10962/d1017353
  • Description: This research report documented in this thesis focused mainly on the participation of grade 9 girls during practical work in the topic of ‘Electricity’ in Physical Science lessons at Mwatya (pseudonym) Junior Secondary School in Ohangwena region of Namibia. The study was triggered by the lack of participation of girls during practical work. Underpinned by an interpretive paradigm, the study took the form of a qualitative case study and my unit of analysis was girls’ participation during practical work on electricity in particular. The perceptions and experiences of girls about practical work in Physical Science were investigated using the administered questionnaires. The participation of girls during practical work was further explored using interviews (semi-structured and focus group interviews) and observations of selected girls. A thematic approach to data analysis was adopted. The qualitative data from the audio and video transcripts were analysed according to the categories developed and themes that emerged from the analysis process. The categories developed for presenting the data are: teaching methods preferred by girls; importance and roles of practical activities; things that girls enjoy during practical activities; problems experienced by girls during practical activities; preference for doing practical work in groups or as an individual task; if practical work given in groups should the sex of learners be considered or not; activities preferred by girls when they are in single sex and in mixed sex groups; factors that enable girls to participate; and factors that prevent girls from participating. The study found that girls’ perceptions about practical work affect their participation during practical work in the topic of Electricity. It also revealed different factors that contribute to either good or poor participation of girls, namely, factors such as mixed-sex group-work, limited science prior experience (knowledge), unequal treatment from teachers during lessons and home environment were identified as contributing to poor participation. Girls however suggested some factors that they think could enable them to participate freely and actively during practical work. In view of these findings, this study recommends that teacher training institutions should train teachers to plan practical work in a gender sensitive manner. Schools should be provided with enough materials as sharing materials can contribute to poor participation of girls during practical work especially when they are in mixed groups with boys. There is a need for science teachers to assess the learning taking place during practical work and, finally, textbook suppliers should be monitored in a way that enables the supply of gender sensitive printed materials.
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  • Date Issued: 2015

An investigation into how two Grade 11 Physical Science teachers mediate learning of the topic chemical equilibrium : a case study

  • Authors: Chani, Fungisisai M
  • Date: 2015
  • Subjects: Chemical equilibrium -- Study and teaching (Secondary) -- Namibia , Science -- Study and teaching (Secondary) -- Namibia
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:2023 , http://hdl.handle.net/10962/d1017334
  • Description: The Namibian Physical Science Higher Level Syllabus requires students to study the topic on chemical equilibrium. This section has proven to be one of the most difficult for Namibian learners as reflected by their poor responses to questions in the Grade 12 NSSC ‘H’ examinations. Triggered by these discoveries, I decided to conduct a research on how teachers mediate learning of the topic on chemical equilibrium in a Namibian context. Conducted at a private school in Windhoek, the study involved two experienced Grade 11 Physical Science teachers renowned for good results. I adopted a qualitative case study underpinned by an interpretive paradigm. Sense making of concepts on chemical equilibrium was my unit of analysis. To generate data, I used document analysis, semi-structured interviews, lesson observations, which were videotaped as well as stimulated recall interviews. Vygotsky’s mediation of learning and social constructivism blended with Shulman’s pedagogical content knowledge (PCK) were the theoretical frameworks adopted in the study. During the analysis process, there was grouping of data into categories. These included teacher-learner interactions as emphasized by Vygotsky’s mediation of learning and learners’ challenges according to PCK. I used an inductive approach to identify emerging themes from my data. The themes were colour coded and the developed into analytical statements. Data triangulation, member checking, and peer review ensured data validity and trustworthiness. Stimulated recall interviews conducted while watching the videos with the two teachers, complemented these approaches. My findings were that teachers extensively used various meditational tools such as prior knowledge, language, analogies and an equilibrium game to mediate learning. The teachers experienced numerous challenges during mediation of learning, including language difficulties and learners’ failure to comprehend complex chemical equilibrium concepts. Notwithstanding, the teachers in this study managed to some extent to overcome the challenges by exhibiting facets of advanced PCK.
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  • Date Issued: 2015

An investigation into how two Natural Science teachers in the Khomas region mediate learning of the topic of atoms and molecules in Grade 7 : a case study

  • Authors: Hoepfner, Narenda
  • Date: 2015
  • Subjects: Science -- Study and teaching (Elementary) -- Namibia -- Khomas , Life sciences -- Study and teaching (Elementary) -- Namibia -- Khomas , Pedagogical content knowledge , Cognitive learning , Teachers -- In-service training -- Namibia -- Khomas
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:2031 , http://hdl.handle.net/10962/d1017342
  • Description: The teaching of abstract concepts requires higher cognitive thinking skills and thus presents a challenge for most subjects in the curriculum, in particular, science subjects. Teachers often complain that they struggle to develop higher cognitive skills in learners in such topics. As a result, learners fail to understand science concepts and then complain that science is boring and hence lose interest in the subject. The main reason for this study was to investigate how Grade 7 Natural Science teachers mediate the learning of abstract topics, in particular, atoms and molecules which are regarded as the building blocks in chemistry. This study further sought to develop a teaching unit of work on atoms, molecules and the Periodic Table in partnership with the participating teachers, in order to help improve teaching and learning of the topic. The study is located within an interpretive paradigm. Within this paradigm, a qualitative case study approach was adopted whereby two Grade 7 Natural Science teachers in the Khomas Region were the research participants. This approach enabled me to seek for answers beyond the obvious classroom experiences by using document analysis, semi-structured interviews and classroom observation (which were video-taped and transcribed). The theoretical frameworks underpinning this study focused on mediation of learning and social constructivism as expounded by Vygotsky, in conjunction with Shulman’s pedagogical content knowledge. Hence, emphasis was placed on the teaching strategies used by teachers, such as elicitation of prior knowledge during the lessons, language used, interaction of learners and ways how teachers deal with the challenges faced by them in the mediation of learning. An inductive analysis to discover patterns and themes was applied during the data analysis process. The themes were further turned into analytical statements to interpret the data. The validation process was achieved by using a variety of data gathering techniques. I watched the videotaped lessons with the observed teachers and I made use of member checking in the form of stimulated recall interviews and transcripts of the interviews. Thus, a summary of discussions were given back to the respondents to verify their responses and check for any misinterpretations. Different chapters of my study were given to colleagues to read through as a means of the validation process. Herein lies the importance of a critical friend in qualitative research. The findings of the study revealed that concepts of high cognitive demand should not be oversimplified when introduced to learners, as learners might find it difficult to define and conceptualise concepts as they do not have proper insights into the concepts. The findings further illuminated that teachers should develop a strong subject content knowledge as well as pedagogical content knowledge to have the best strategies in place to mediate learning of this topic. The study concludes, with Phase 2, that the exposure of and cooperation between teachers plays an indispensable role in their professional development. Essentially, this enables teachers to make use of different teaching styles as they scaffold learners in the process of making sense of, in particular, abstract science concepts. Finally, this study recommends that teachers need to engage in on-going professional development opportunities and be equipped with suitable learning support and other necessary physical resources, as a way of motivation and to be in a position to deal with all the many challenges they have to face during the mediation of learning.
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  • Date Issued: 2015

An investigation into how Zimbabwe's Bulawayo viewers negotiate the gay storyline in Generations

  • Authors: Khumalo, Senziwani
  • Date: 2015
  • Subjects: Generations (Television program) , Homosexuality on television , Homosexuality -- Social aspects -- Zimbabwe -- Bulawayo , Homosexuality -- Law and legislation -- Zimbabwe , Homophobia -- Zimbabwe -- Bulawayo , Social psychology -- Zimbabwe -- Bulawayo
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:3543 , http://hdl.handle.net/10962/d1017784
  • Description: This study seeks to evaluate how aspects of religion, culture, political context, education and class, amongst others, impact on the manner with which Zimbabwe’s Bulawayo residents make sense of media messages which explore issues of homosexuality, as encountered in the soap opera Generations. This is against the backdrop of Zimbabwean legislation, such as the Sexual Deviancy Act, which criminalises homosexuality and the state victimisation of gays and lesbians in this country. The inclusion of homosexual liberties was rejected by all political parties and both public and private media in the recent drafting of a new rule of law. The legislation, including gay rights exclusion in the new constitution, and state action has perpetuated an impression that Zimbabwe is a deeply homophobic society. As a starting point the study examines the claims of the media imperialism thesis which supposes an all-consuming power of western media and next examines Straubhaar’s thesis of ‘cultural proximity’ which argues that there is often a preference for regional media, which is proximate to viewers’ local culture, language and identity. The study explores the prominence of South Africa as a regional media player and that proximate identities with some cultures in that country have played a role in drawing some Bulawayo viewers to South African television, as they feel slighted by Zimbabwean media. Utilising qualitative research methods, the study explores whether or not the representation of gay images on this South African soap opera provides viewers with opportunities for ‘symbolic distancing’. The concept highlights that when people have insight into lifestyles that are different from their own, they use that as a resource to critically analyse their own lives and cultural understandings. The study evaluates if Bulawayo viewers’ sentiments towards homosexuality has been challenged and changed through their interface with the soap opera, Generations.
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  • Date Issued: 2015

An investigation into literacy development in Grade 4 English and isiXhosa home language textbooks : a comparative study

  • Authors: Fulani, Ntombekhaya Cynthia
  • Date: 2015
  • Subjects: Progress in International Reading Literacy Study , Literacy -- South Africa , Textbooks -- South Africa -- Criticism, Textual , English language -- Study and teaching (Elementary) , Xhosa language -- Study and teaching (Elementary)
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:2055 , http://hdl.handle.net/10962/d1018914
  • Description: The 2006 Progress in International Reading Literacy Study (PIRLS) painted a gloomy picture of South African literacy when South Africa came last out of 40 countries. It was from this background that my study set out to investigate two English and two isiXhosa grade 4 home language textbooks with their accompanying teachers’ guides from two publishing houses, together with the home language curriculum documents for English and Xhosa because they are an important component in literacy development. It is important to emphasise that this study examined textbooks, not how teachers mediate such textbooks in their classrooms. In other words, my focus was on the textbooks themselves, and it was primarily through textual analysis of this stable, readily available data that I have been able to compare and analyse the potential they offer learners and teachers to achieve the literacy goals prescribed by the curriculum. The study also investigated the likelihood of differential attainment for learners as a result of using these textbooks. This was done by looking at whether the textbooks were in line with the literacy outcomes for English and isiXhosa home languages. It also looked at the kind of reader/writer envisaged in the selected textbooks and the level of challenge the selected textbooks offer and how, if at all, learners are encouraged to be critical readers and writers. The findings of the study were that the English and isiXhosa textbooks of each publishing house envisaged different learners. The English textbooks envisaged a cosmopolitan learner who has greater access to academic literacy. While the isiXhosa textbooks envisaged a parochial learner who has less access to academic literacy compared to the English learner
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  • Date Issued: 2015

An investigation into the feasibility of incorporating ketoconazole into solid lipid microparticles

  • Authors: Jhundoo, Henusha Devi
  • Date: 2015
  • Language: English
  • Type: text , Thesis , Masters , MPharm
  • Identifier: http://hdl.handle.net/10962/54701 , vital:26601
  • Description: One of the major challenges of the oral administration of ketoconazole (KTZ), an inhibitor of sterol 14α demethylase, used in the management of systemic and topical mycoses in immuno-compromised and paediatric patients is the lack of availability of liquid dosage forms. In order to overcome this challenge, extemporaneous preparations have been manufactured by care-givers and health care providers by crushing or breaking solid oral dosage forms of KTZ and mixing with a vehicle to produce a liquid dosage form that can be swallowed by patients. However, the use of extemporaneous preparations may lead to under or over-dosing if the care-givers are not guided accordingly. Furthermore, the dearth of information on the stability of these KTZ-containing extemporaneous preparations may lead to ineffective antifungal therapy and complicate the problems of resistance as it is difficult to estimate the shelf-lives of these extemporaneous products under varying storage conditions due to the susceptibility of KTZ to chemical degradation. Therefore, there is a need for formulation scientists to develop novel drug delivery systems that avoid the need for extemporaneous preparations, possess well-established limits of stability and minimize the risks of systemic adverse effects to facilitate KTZ therapy. The use of solid lipid microparticles (SLM) as potential carriers for the oral administration of KTZ was investigated since solid lipid carriers are known to exhibit the advantages of traditional colloidal carriers. The research undertaken in these studies aimed to investigate the feasibility of developing and manufacturing solid lipid microparticles (SLM), using a simple micro-emulsion technique, as a carrier for KTZ. Prior to pre-formulation, formulation development and optimization studies of KTZ-loaded SLM, it was necessary to develop and validate an analytical method for the in vitro quantitation and characterization of KTZ in aqueous dispersions of SLM during development and assessment studies. An accurate, precise, specific and sensitive reversed-phase high performance liquid chromatographic (RP-HPLC) method coupled with UV detection at 206 nm was developed, optimized and validated for the analysis of KTZ in formulations. Formulation development studies were preceded by solubility studies of KTZ in different lipids. Labrafil® M2130 CS was found to exhibit the best solubilising potential for KTZ. Pre-formulation studies were also designed to determine the polymorphic behavior and the crystallinity of KTZ and Labrafil® M2130 CS that was used for subsequent manufacture of the solid lipid carriers. DSC and FTIR studies revealed that there were no changes in the crystallinity of KTZ or Labrafil® M2130 CS following exposure to a temperature of 60°C for 1 hour. In addition the potential for physicochemical interaction of KTZ with the lipid Labrafil® M2130 CS was investigated using DSC and FTIR and the results revealed that KTZ was molecularly dispersed in Labrafil® M2130 CS and that it is unlikely that KTZ would interact with the lipid. It was therefore established that KTZ and Labrafil® M2130 CS were thermo-stable at a temperature of 60°C and thus a micro-emulsion technique could be used to manufacture the KTZ-loaded SLM. Drug-free and KTZ-loaded SLM were prepared using a modified micro-emulsion technique that required the use of an Ultra-Turrax® homogenizer set at 24 000 rpm for 5 minutes followed by the use of the Erweka GmbH homogenizer. SLM were characterized in terms of particle size (PS), zeta potential (ZP), shape and surface morphology using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). In addition drug loading capacity (DLC) and encapsulation efficiency (EE) of SLM for KTZ were assessed using RP-HPLC. Formulation development and optimization studies of KTZ-loaded SLM were initially aimed at selecting an emulsifying system that was able to stabilize the SLM in an aqueous dispersion. Successful formulations were selected based on their ability to remain physically stable on the day of manufacture. Pluronic® F68 used in combination with Lutrol® E40, Soluphor® P, Soluplus® produced unstable dispersions on the day of manufacture and these combinations were not investigated further. However, the formulation of a stable KTZ-loaded SLM dispersion was accomplished by use of a combination of Pluronic® F68, Tween 80 and sodium cholate as the surfactant system. Increasing amounts of Labrafil® M2130 CS resulted in the production of particles with low DLC and EE, a large PS and a relatively unchanged ZP. An optimum concentration of 10% w/v Labrafil® M2130 CS was selected to manufacture the KTZ-loaded SLM. Studies to determine the influence of KTZ loading on the quality of SLM revealed that concentrations of KTZ > 5% w/v led to a reduction in DLC and EE and an increase in PS with minimal impact on the ZP. Stability studies conducted at 25°C/65% RH and 40°C/75% RH for up to 30 days following manufacture revealed that batch SLM 15 manufactured using 10% w/v Labrafil® M2130 CS, 5% w/v KTZ and a combination of 4% w/v Pluronic® F-68, 2% w/v Tween 80 and 1% w/v sodium cholate produced the most stable dosage form when stored at 25°C/65% RH for up to 30 days. However, storage at 40°C/75% RH resulted in instability of the formulation. An aqueous dispersion of KTZ-loaded SLM has been developed and assessed and may offer an alternative to extemporaneous preparations used for KTZ therapy in paediatric and immuno-compromised patients.
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  • Date Issued: 2015

An investigation into the mathematics teaching practices of non-isiXhosa-speaking teachers teaching isiXhosa-speaking 3rd Graders through the medium of Afrikaans

  • Authors: Knoetze, Susanna
  • Date: 2015
  • Subjects: Mathematics -- Study and teaching (Elementary) -- South Africa -- Grahamstown , Language and education -- South Africa -- Grahamstown , Education, Elementary -- Evaluation -- South Africa -- Grahamstown , Mathematics teachers -- Rating -- South Africa -- Grahamstown , Language arts -- Correlation with content subjects -- South Africa -- Grahamstown , Native language and education -- South Africa -- Grahamstown , Second language acquisition , Xhosa language , Afrikaans language
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:2054 , http://hdl.handle.net/10962/d1018910
  • Description: There is a considerable body of literature on the challenges faced by learners who speak an African language at home but who are taught through the medium of English. Less research has focused, however, on contexts where isiXhosa-speaking learners have Afrikaans as their Language of Learning and Teaching (LoLT), especially in Foundation Phase classrooms where teachers may not speak their learners’ home language. Such learners face the triple challenge of simultaneously learning a second language, learning to read in that language, and also learning new content and concepts through it. Using a multiple case study design, this investigation explores the mathematics teaching practices of Afrikaans-speaking Grade 3 teachers teaching isiXhosa-speaking learners through the medium of Afrikaans. Separate contextual profiles of the teaching practices of the participating teachers at the three schools are presented. Data were derived from school, classroom, and lesson observations (at least five complete mathematics lessons of each teacher), plus interviews with the teachers and with their school principals. By drawing on Vygotskian sociocultural theory and the interactive model of second language acquisition, this study highlighted the teaching practices of the three teachers as they mediated their learners’ mathematical conceptual development. An inductive data analysis approach was used to isolate recurring themes and patterns. Four main themes were identified: structuring of teaching and learning, facilitating of interaction, language use and implementation of mediating strategies. Analysis of the data shows that all three teachers’ language use displayed high levels of modified input, and high levels of context-embedded support. The levels of scaffolded learner talk were, however, found to be much lower than the levels of teacher talk, especially as far as academic registers were concerned. The teachers’ mediation strategies also displayed high levels of teacher-directed input which, on the whole, did not provide optimal opportunities for learners to develop independent levels of academic discourse. The study highlights the need for further research to inform teacher education and development with regard to more effective support structures to assist teachers with the sorts of challenges outlined above.
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  • Date Issued: 2015

An investigation into the nature of mathematical connections selected grade 7 teachers make when teaching fractions : a Namibian case study.

  • Authors: Amupolo, Loide M
  • Date: 2015
  • Subjects: Mathematics -- Study and teaching -- Namibia , Fractions -- Study and teaching -- Namibia
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:2016 , http://hdl.handle.net/10962/d1016374
  • Description: The general understanding of mathematics as a subject and its implications is, in reality alarmingly low. Evidence of this is evident in learners’ performance and their reaction towards the subject. Fractions as a domain of Mathematics are no exception. The majority of the learners do not learn Fractions comfortably. The causes of this may be varied. However, it is believed that one way of ensuring meaningful teaching and learning is to make use of appropriate connections. The significance and the important role of the teacher in making mathematical connections in learning for understanding are well documented in the literature. This study focuses on the nature of mathematical connections selected Grade 7 teachers make when teaching Fractions, as well as their perceptions of the importance of making such connections. This qualitative case study was conducted in three schools in the Oshana region. The purpose was to investigate how mathematics teachers make connections in fractions. Underpinned by an interpretive paradigm, the study made use of observations and interviews to generate data. The framework borrowed from Businkas’ (2008) study was used in analysing and coding the nature of connections used in the lessons observed. An individual conversation on the nature and perceptions of the connections made in the observed lessons was undertaken with each teacher followed by a focus group discussion that aimed at analysing deeper perceptions on connections. The main findings of the study revealed that teachers made use of all the different types of connections as per Businkas’s framework. The frequency of occurrence showed that Instruction-Oriented Connection and Multiple Representation connections topped the list of connections used. Teachers pointed out that connections to prior knowledge and making multiple representations were most significant, as they related to learners’ existing knowledge and pointed to different ways of solving a problem. The teachers were, however, not familiar with the other connections identified as this was their first experience of interrogating connections. They, however, agreed on the importance of making those connections. The teachers agreed that meaningful connections indeed helped with their conceptual understanding of Mathematics. They believed that connections can increase learners’ interest in school and help reduce negative views of fractions, in particular, and mathematics in general. However, they felt that the limited number of resources, poor teaching approaches and the inability of creating fraction sense may hinder them from making appropriate connections.
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  • Date Issued: 2015

An investigation into the nature of mathematics connections used by selected Grade 11 teachers when teaching algebra : a case study

  • Authors: Kanyanda, Ester Ndahekomwenyo
  • Date: 2015
  • Subjects: Mathematics -- Study and teaching (Secondary) -- Namibia -- Tsumeb , Algebra -- Study and teaching (Secondary) -- Namibia -- Tsumeb , Connections (Mathematics) , Teacher effectiveness -- Namibia -- Tsumeb
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:2036 , http://hdl.handle.net/10962/d1017347
  • Description: The purpose of this study was to investigate the nature of mathematical connections used by selected teachers when teaching the topic of algebra and to investigate their perceptions of their use of connections. The participants were selected on the basis of teaching experience as well as their willingness to share their ideas. An interpretive paradigm was used to collect and analyse data. The data was collected from three participating teachers. These participants were selected from the three secondary schools in the town of Tsumeb in Namibia. I used video recordings of two lessons per teacher as well as semi-structured interviews as my tools to gather data. After the two lessons were video recorded, I conducted a workshop with the teachers to introduce them to the 5 types of mathematical connections pertinent to this study. We analysed the videos together using Businskas' framework as a basis for analysis. This then formed part of the stimulated recall interviews. It was found that, even though teachers were not aware of the concept of mathematical connections before our interactions, there was strong evidence of connections being made and used in their lessons. The two types of connections that were used most frequently (24.1 percent each) were procedural and instruction-oriented connections respectively. Part-whole relationships connections were used the least with a frequency of 12 percent. All three teachers agreed that they needed to make more connections when teaching and that they would think more about connections in future, particularly when preparing their lessons. The study makes recommendations to encourage the continuous use of connections in teaching mathematics.
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  • Date Issued: 2015

An investigation into the perceptions of female academics on their career development: a comparative study of South African and Zimbabwean universities

  • Authors: Chitsamatanga, Bellita Banda
  • Date: 2015
  • Subjects: Career development -- Education (Higher) -- Africa , College teachers -- Africa , Universities and colleges -- Africa
  • Language: English
  • Type: Thesis , Masters , M Ed
  • Identifier: vital:16223 , http://hdl.handle.net/10353/d1019735 , Career development -- Education (Higher) -- Africa , College teachers -- Africa , Universities and colleges -- Africa
  • Description: This study investigated the perceptions of female academics on their career development in South African and Zimbabwean universities. The study attempted to unravel the story of the female academics which must be heard but is seldom accorded the space within the academia. The interpretive paradigm was utilised in this study because it focuses on individual perceptions and experiences. In addition a qualititative approach was employed for the collection of data since it allowed for triangulation of data collection techniques so as to gain in-depth and rich information on the career trajectory of female academics in South African and Zimbabwean universities. Therefore, semi-structured interviews, focus group interviews and document analysis were employed. The participants were purposively selected for the sample of this study and comprised of 5 senior female academics from each university and 5 junior female academics also representing each university respectively. Thematic content analysis was used to analyse data and this was carried out in line with the research questions, aims and objectives of the study. Through the participants' answers from both universities under study, a transcript was formulated, coded and categorised in view of the career development of female academics in South African and Zimbabwean universities. It was discovered from the data that the female academics still encounter a number of challenges with regard to their career mobility both in and out of academia inter alia, (1) gender stereotyping and male domination (2) knowledge retention (3) lack of mentorship and organisational support especially through funding and professional staff development programmes (4) lack of female solidarity (5) under-representation of female academics (6) teaching workloads and research publications and (7) lack of family support, were illuminated by the participants as common fixtures that hinder their career development in academia. Moreover, there were variances in both universities under study especially with relations to funding, gender policies in place and male domination. Consequently, the above mentioned factors were more pronounced in Zimbabwean universities than in South African universities. As a result, emphasis was that both South African and Zimbabwean universities have to draw a line between theory and practice especially on the professional staff development programmes that are offered to the academics. A crucial observation was made by the researcher on how most of the participants from both universities under study had negotiated their roles as mothers, wifes, academic and sisters in a bid to realise career growth, such that striking a balance between work and family posed a continuous hindrance their career development. As a result, hard work, commitment, confidence, self-assertiveness and sacrifice cut across both universities as strategies used if the battle of career development of female academics had to be won. In sum, this study attempted to illuminate the perceptions and experiences of female academics and what it means to be a female academicin the 21st century universityn and why there is a need to create, cultivate and have a conducive and supportive working environment. Moreover, promotion of knowledge expansion and sharing, gender equity and equality needs to be employed by both universities under research. Additionally, the professtional staff development programmes offered need to be conducted by qualified and experienced personnel in a bid to avoid repetition of workshops and training programs. Furthermore, formalisation of mentoring and role modelling should also be employed by South African and Zimbabwean universities. Lastly, the study recommended that there is a need for universities source out resources for its academics if there are to produce well rounded scholars who will be able to experience career development.
  • Full Text:
  • Date Issued: 2015
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