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Core-modified rubyrins with phenanthrene-fused pyrrole rings

  • Authors: Yuan, Xuemei , Li, Minzhi , Meng, Ting , Mack, John , Soy, Rodah , Nyokong, Tebello , Zhu, Weihua , Xu, Haijun , Liang, Xu
  • Date: 2018
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/234568 , vital:50209 , xlink:href="https://doi.org/10.1016/j.dyepig.2018.05.045"
  • Description: Three fused-ring-expanded rubyrins with modified macrocyclic core have been synthesized and characterized. A series of spectroscopic, electrochemical measurements and a set of theoretical calculations demonstrate that the core-modification of the inner core of rubyrins has a large influence on the electronic structure. Colorimetric changes are observe that demonstrate that these core-modified rubyrins could be used as selective Hg2+ ion sensors. These properties can be fine-tuned by introducing lipophilic substituents on the meso-aryl rings.
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Cropland abandonment in South African smallholder communal lands: Land cover change (1950–2010) and farmer perceptions of contributing factors

  • Authors: Blair, Dale , Shackleton, Charlie M , Mograbi, Penelope J
  • Date: 2018
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/180297 , vital:43351 , xlink:href="https://doi.org/10.3390/land7040121"
  • Description: Despite agricultural land abandonment threatening the food security and the livelihoods of smallholder farmers, it is pervasive globally and in developing countries. Yet land abandonment is an understudied aspect of land use change in social–ecological systems. Here we provide more information on this phenomenon by exploring cropland abandonment during 1950–2010 in four former South African ‘homelands’—part of the ‘Apartheid’ era racially-based land allocation programs—characterized by rural, smallholder farmers. Cropland abandonment 1950–2010 was widespread in all surveyed sites (KwaZulu: 0.08% year−1, Transkei: 0.13% year−1, Lebowa: 0.23% year−1, Venda: 0.28% year−1), with rates peaking between 1970 and 1990, with concomitant increases (up to 0.16% year−1) of woody vegetation cover at the expense of grassland cover. Active and past farmers attributed cropland abandonment to a lack of draught power, rainfall variability and droughts, and a more modernized youth disinclined to living a marginal agrarian lifestyle. We discuss the potential social and ecological implications of abandoned croplands at the local and regional scales, as the deagrarianization trend is unlikely to abate considering the failure of current South African national agricultural incentives.
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Cultural De-colonization versus Liberal approaches to abortion in Africa: The politics of representation and voice

  • Authors: Chiweshe, Malvern T , Macleod, Catriona I
  • Date: 2018
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/443661 , vital:74142 , xlink:href="DOI/Handle/URL https://www.ajol.info/index.php/ajrh/article/view/175092"
  • Description: Political discussions on abortion in Africa take place in the context of most countries having restrictive abortion legislation and high levels of unsafe abortion. In this paper two major political positions regarding abortion in Africa: a de-colonisation approach based on a homogenized view of ―culture‖, and a liberal approach based on ―choice‖ and rights are outlined. Using the Questions and Answers sessions of a United Nations event on maternal health in Africa as an exemplar of these positions, the paper argues that neither approach is emancipatory in the African context. A de-colonisation approach that uses static and homogenized understanding of ''culture'' risks engaging in a politics of representation that potentially silences the ―Other‖ (in this case women who terminate their pregnancies) and glosses over complexities and multiple power relations that exist on the continent. A liberal approach, premised on choice and reproductive rights, risks foregrounding individual women‘s agency at the expense of contextual dynamics, including the conditions that create unsupportable pregnancies. The paper argues for a grounded reproductive justice perspective that draws on the insights of the reproductive justice movement, but grounds these notions within the African philosophy of Hunhu/Ubuntu.
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Current trend in synthesis, Post-Synthetic modifications and biological applications of Nanometal-Organic frameworks (NMOFs)

  • Authors: Baa, Ebenezer , Watkins, Gary M , Krause, Rui W M , Tantoh, Derek N
  • Date: 2018
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/127042 , vital:35946 , https://doi.org/10.1002/cjoc.201800407
  • Description: Since the early reports of MOFs and their interesting properties, research involving these materials has grown wide in scope and applications. Various synthetic approaches have ensued in view of obtaining materials with optimised properties, the extensive scope of application spanning from energy, gas sorption, catalysis biological applications has meant exponentially evolved over the years. The far‐reaching synthetic and PSM approaches and porosity control possibilities have continued to serve as a motivation for research on these materials. With respect to the biological applications, MOFs have shown promise as good candidates in applications involving drug delivery, BioMOFs, sensing, imaging amongst others. Despite being a while away from successful entry into the market, observed results in sensing, drug delivery, and imaging put these materials on the spot light as candidates poised to usher in a revolution in biology. In this regard, this review article focuses current approaches in synthesis, post functionalization and biological applications of these materials with particular attention on drug delivery, imaging, sensing and BioMOFs.
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Dangerous liaisons or critical alliances: student perceptions of community engagement at Rhodes University, South Africa

  • Authors: Levy, Simone Arielle
  • Date: 2018
  • Subjects: Rhodes University -- Students -- Public services , Community and college -- South Africa -- Eastern Cape , Education, Higher -- Social aspects -- South Africa
  • Language: English
  • Type: text , Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/57411 , vital:26907
  • Description: Community Engagement (CE) in South Africa is an increasingly important feature of the relationship between the university and a broader community, and may aid in bridging the entrenched social divisions of this nation. This will only be possible if CE succeeds in uniting the knowledge production interests of the university and the broader community. Through CE, knowledge production and dissemination from within the university should be made more relevant and applicable because it is based on a relationship or engagement with a community. Based on the perceptions of student volunteers in a CE programme at a South African university, this thesis set out to ask whether or not students are transformed through university-community collaboration. This research examines the perceptions and motivations of student volunteers entering community partnership programmes. More importantly, it asks whether these engagements are merely a “weekend special” consisting of shallow engagements, which last only a few hours a week that provide institutional window dressing; or well-intended engagements through which students build meaningful relationships and experience learning opportunities that prepare them for real world civic participation. As this thesis focuses on the student perspective, it explores whether or not CE has an impact, both personally and educationally or academically, on the lives of individual student volunteers. The literature on CE argues that students’ participation in CE opportunities should enhance academic learning, personal growth and promote a sense of citizenship or civic responsibility. Based on the perceptions of a small group of student volunteers at one university, this thesis identifies possible successes and limitations of CE volunteering programmes in order to see if what is promoted in the literature or institutional policies is being experienced or achieved in practice at universities. I argue that students are indeed transformed through processes of CE, often in unexpected ways, and despite many difficulties. Therefore, if CE provides students with more holistic learning opportunities while attending universities for academic ends, it is important to look at in what ways this is achieved.
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De-identification of personal information for use in software testing to ensure compliance with the Protection of Personal Information Act

  • Authors: Mark, Stephen John
  • Date: 2018
  • Subjects: Data processing , Information technology -- Security measures , Computer security -- South Africa , Data protection -- Law and legislation -- South Africa , Data encryption (Computer science) , Python (Computer program language) , SQL (Computer program language) , Protection of Personal Information Act (POPI)
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/63888 , vital:28503
  • Description: Encryption of Personally Identifiable Information stored in a Structured Query Language Database has been difficult for a long time. This is owing to block-cipher encryption algorithms changing the length and type of the input data when encrypted, which cannot subsequently be stored in the database without altering its structure. As the enactment of the South African Protection of Personal Information Act, No 4 of 2013 (POPI), was set in motion with the appointment of the Information Regulators Office in December 2016, South African companies are intensely focused on implementing compliance strategies and processes. The legislation, promulgated in 2013, encompasses the processing and storage of personally identifiable information (PII), ensuring that corporations act responsibly when collecting, storing and using individuals’ personal data. The Act comprises eight broad conditions that will become legislation once the new Information Regulator’s office is fully equipped to carry out their duties. POPI requires that individuals’ data should be kept confidential from all but those who specifically have permission to access the data. This means that not all members of IT teams should have access to the data unless it has been de-identified. This study tests an implementation of the Fixed Feistel 1 algorithm from the National Institute of Standards and Technology (NIST) “Special Publication 800-38G: Recommendation for Block Cipher Modes of Operation : Methods for Format-Preserving Encryption” using the LibFFX Python library. The Python scripting language was used for the experiments. The research shows that it is indeed possible to encrypt data in a Structured Query Language Database without changing the database schema using the new Format-Preserving encryption technique from NIST800-38G. Quality Assurance software testers can then run their full set of tests on the encrypted database. There is no reduction of encryption strength when using the FF1 encryption technique, compared to the underlying AES-128 encryption algorithm. It further shows that the utility of the data is not lost once it is encrypted.
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Decentralization and quality assurance in the Ugandan primary education sector

  • Authors: Abu-Baker, Mutaaya Sirajee
  • Date: 2018
  • Subjects: Schools -- Decentralization -- Uganda , Education, Primary -- Uganda , Educational change -- Uganda
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/57390 , vital:26897
  • Description: The study presented in this thesis is a case study analysis of decentralization and quality assurance in a decentralized set up of the Ugandan Primary Schooling. The research looked at how the monitoring and evaluation informed the policy formulation process to regulate quality assurance in a decentralized governance of primary education. The Study was positioned in the critical realist paradigm, interpretive in orientation and used both coding and thematic techniques to understand the teachers’, SMC members’, and officers’ (at district and ministry levels) experiences and perceptions of quality assurance in a decentralized set up. Data was gathered using interviews, document analysis and observation methods. The findings indicated that the study was affected by eleven themes: Management System and Leadership, Human Resource Management, Finance Administration and Management, Parenting and Nutrition, Politics, Motivation, Social Structures and Patterns, Legislative Process and Policies, Infrastructure Development and Management, Community Involvement in Education and Curriculum and Professionalism. The monitoring and evaluation system had a framework in which it operates, though there was no quality assurance policy to guide the provision of quality education. The study finally indicated that there are more threats in a decentralized set up that put Quality in danger. Secondly, there was absence of supervision/inspection in schools as there was no evidence to prove this due to absence of reports. However, document analysis indicated visits of officers to schools. Records management was a problem to schools. Decentralization was adopted at different levels by different countries to address specific problems identified in view of service delivery. Finally, though monitoring and evaluation results informed the policy and decision makers, there was no quality assurance policy to guide the provision of quality education in institutions.
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Demographic change in the Upper Tsitsa Catchment: the integration of census and land cover data for 2001 and 2011

  • Authors: Hodgson, Danuta Lorina
  • Date: 2018
  • Subjects: Land use -- South Africa -- Eastern Cape , Watersheds -- South Africa -- Eastern Cape , Thematic maps -- South Africa -- Eastern Cape , Population density -- South Africa -- Eastern Cape , Mzimvubu River Watershed (South Africa) -- Census , Upper Tsitsa Catchment (South Africa)
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/57296 , vital:26870
  • Description: The purpose of this research was to determine if the integration of census and land cover data could provide evidence of spatial patterns and temporal change for the Upper Tsitsa Catchment. This thesis contributed to academic literature with regards to dasymetric mapping and provided a database for the Ntabelanga and Laleni Ecological Infrastructure Project. The study took place in the Upper Tsitsa Catchment which is located in the north-eastern region of the Eastern Cape and falls within the uMzimvubu Catchment. South Africa National Population Censuses for 2001 and 2011 and the National Land Cover data sets for 2000 and 2013/14 were used to create dasymetric maps depicting demographic changes over time for the catchment area. Spatial statistics were performed on the dasymetric and choropleth map to determine the accuracy of the data that was created. From the results, it was found that although the statistics were skewed, the method was more accurate in displaying the population densities, which was noted during the sampling process of the spatial analysis. It was found that there had been a decrease in the population density within the catchment. This affected the density of several other variables such as population race group, language and employment status statistics as decreases in these values could be due to individuals migrating out of the catchment as well as socio-economic upliftment, such as having better access to services. The use of dasymetric mapping allowed an accurate representation of the population density from the census data to be created. The results of the dasymetric mapping were more accurate as they depicted where the population within the enumeration areas were located, and recognised that some areas were populated while some areas were not. To conclude, it was found that using dasymetric mapping provided reliable and useful data about population density and enables comparison over time.
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Designing and prototyping WebRTC and IMS integration using open source tools

  • Authors: Motsumi, Tebagano Valerie
  • Date: 2018
  • Subjects: Internet Protocol multimedia subsystem , Session Initiation Protocol (Computer network protocol) , Computer software -- Development , Web Real-time Communications (WebRTC)
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/63245 , vital:28386
  • Description: WebRTC, or Web Real-time Communications, is a collection of web standards that detail the mechanisms, architectures and protocols that work together to deliver real-time multimedia services to the web browser. It represents a significant shift from the historical approach of using browser plugins, which over time, have proven cumbersome and problematic. Furthermore, it adopts various Internet standards in areas such as identity management, peer-to-peer connectivity, data exchange and media encoding, to provide a system that is truly open and interoperable. Given that WebRTC enables the delivery of multimedia content to any Internet Protocol (IP)-enabled device capable of hosting a web browser, this technology could potentially be used and deployed over millions of smartphones, tablets and personal computers worldwide. This service and device convergence remains an important goal of telecommunication network operators who seek to enable it through a converged network that is based on the IP Multimedia Subsystem (IMS). IMS is an IP-based subsystem that sits at the core of a modern telecommunication network and acts as the main routing substrate for media services and applications such as those that WebRTC realises. The combination of WebRTC and IMS represents an attractive coupling, and as such, a protracted investigation could help to answer important questions around the technical challenges that are involved in their integration, and the merits of various design alternatives that present themselves. This thesis is the result of such an investigation and culminates in the presentation of a detailed architectural model that is validated with a prototypical implementation in an open source testbed. The model is built on six requirements which emerge from an analysis of the literature, including previous interventions in IMS networks and a key technical report on design alternatives. Furthermore, this thesis argues that the client architecture requires support for web-oriented signalling, identity and call handling techniques leading to a potential for IMS networks to natively support these techniques as operator networks continue to grow and develop. The proposed model advocates the use of SIP over WebSockets for signalling and DTLS-SRTP for media to enable one-to-one communication and can be extended through additional functions resulting in a modular architecture. The model was implemented using open source tools which were assembled to create an experimental network testbed, and tests were conducted demonstrating successful cross domain communications under various conditions. The thesis has a strong focus on enabling ordinary software developers to assemble a prototypical network such as the one that was assembled and aims to enable experimentation in application use cases for integrated environments.
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Designing writing groups to support postgraduate students’ academic writing: a case study from a South African university

  • Authors: Wilmot, Kirstin
  • Date: 2018
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/66267 , vital:28926 , https://doi.org/10.1080/14703297.2016.1238775
  • Description: publisher version , This paper reports on a writing group pilot programme implemented at a South African university. Drawing on literature, anonymous student evaluations and facilitator observations, it discusses the use of writing groups for supporting postgraduate academic writing practices. Developed within a broader postgraduate academic writing support programme, the paper discusses a case study of two pilot writing groups: a multidisciplinary long-term group and a disciplinary short-term ‘writing-intensive’ group. The findings indicate that the overall experience of the writing group was a positive one, with each group presenting varied ‘success’ aspects as well as challenges. Insights gleaned may contribute to our understanding of how these groups can be utilised to support postgraduate students and how different kinds of groups can be developed to serve particular student needs. The paper concludes with a discussion of the inclusion of a disciplinary expert, which proved particularly useful in this pilot.
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Developing a citizen technician based approach to suspended sediment monitoring in the Tsitsa River catchment, Eastern Cape, South Africa

  • Authors: Bannatyne, Laura Joan
  • Date: 2018
  • Subjects: Sediments (Geology) -- Management , Sediments (Geology) -- South Africa -- Eastern Cape , Watersheds -- South Africa -- Eastern Cape , Suspended sediments -- South Africa -- Eastern Cape , Suspended sediments -- Monitoring -- Citizen participation , Tsitsa River
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/62593 , vital:28211
  • Description: Suspended sediment (SS) in channels is spatiotemporally heterogeneous and, over the long term, is known to be moved predominantly by flood flows with return periods of ~1 - 1.5 years. Flood flows in the Tsitsa catchment (Eastern Cape Province, South Africa) are unpredictable, and display a wide range of discharges. Direct, flood-focused SS sampling at sub-catchment scale was required to provide a SS baseline against which to monitor the impact on SS of catchment rehabilitation interventions, to determine the relative contributions of sub-catchments to SS loads and yields at the site of the proposed Ntabelanga Dam wall, and to verify modelled SS baselines, loads and yields. Approaches to SS sampling relying on researcher presence and/or installed equipment to adequately monitor SS through flood flows were precluded by cost, and the physical and socioeconomic conditions in the project area. A citizen technician (CT)-based flood-focused approach to direct SS sampling was developed and implemented. It was assessed in terms of its efficiency and effectiveness, the proficiency of the laboratory analysis methods, and the accuracy of the resulting SS data. A basic laboratory protocol for SSC analysis was developed, but is not the focus of this thesis. Using basic sampling equipment and smartphone-based reporting protocols, local residents at eleven points on the Tsitsa River and its major tributaries were employed as CTs. They were paid to take water samples during daylight hours at sub-daily timestep, with the emphasis on sampling through flood flows. The method was innovative in that it opted for manual sampling against a global trend towards instrumentation. Whilst the management of CTs formed a significant project component, the CTs benefitted directly through remuneration and work experience opportunities. The sampling method was evaluated at four sites from December 2015 - May 2016. The CTs were found to have efficiently and effectively sampled SS through a range of water levels, particularly in the main Tsitsa channel. An acceptable level of proficiency and accuracy was achieved, and many flood events were successfully defined by multiple data points. The method was chiefly limited by the inability of CTs to sample overnight rises and peaks occurring as a result of afternoon thunderstorms, particularly in small tributaries. The laboratory process was responsible for some losses in proficiency and accuracy. Improved laboratory quality control was therefore recommended. The CT-based approach can be adapted to other spatial and temporal scales in other areas, and to other environmental monitoring applications.
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Developing a multi-sectoral integrative licensing and monitoring framework to align and integrate biodiversity and environmental water quality in the coal mining development life-cycle

  • Authors: Munnik, Victor , Humby, T , Van der Waals, J , Houdet, J , Thompson, Gareth , Keighley, Tia-Kristi , Cobbing, Ben , Palmer, Carolyn G
  • Date: 2018
  • Subjects: To be catalogued
  • Language: English
  • Type: text , report
  • Identifier: http://hdl.handle.net/10962/437825 , vital:73415 , ISBN 978-0-6392-0001-9 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/2355_final.pdf
  • Description: This research report emanates from a fine, which was paid and then transferred to the Water Research Commission for purposes of re-search. As a result of a plea bargain, an agreement was reached in the Ermelo regional court (Mpumalanga) in 2009 (Case no ESH 82/11: Ermelo CAS 462/07/2009), the summary outcome of which is described below.
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Developing an electromagnetic noise generator to protect a Raspberry Pi from side channel analysis

  • Authors: Frieslaar, I , Irwin, Barry V W
  • Date: 2018
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/429511 , vital:72618 , https://ieeexplore.ieee.org/abstract/document/8531950
  • Description: This research investigates the Electromagnetic (EM) side channel leakage of a Raspberry Pi 2 B+. An evaluation is performed on the EM leakage as the device executes the AES-128 cryptographic algorithm contained in the libcrypto++ library in a threaded environment. Four multi-threaded implementations are evaluated. These implementations are Portable Operating System Interface Threads, C++11 threads, Threading Building Blocks, and OpenMP threads. It is demonstrated that the various thread techniques have distinct variations in frequency and shape as EM emanations are leaked from the Raspberry Pi. It is demonstrated that the AES-128 cryptographic implementation within the libcrypto++ library on a Raspberry Pi is vulnerable to Side Channel Analysis (SCA) attacks. The cryptographic process was seen visibly within the EM spectrum and the data for this process was extracted where digital filtering techniques was applied to the signal. The resultant data was utilised in the Differential Electromagnetic Analysis (DEMA) attack and the results revealed 16 sub-keys that are required to recover the full AES-128 secret key. Based on this discovery, this research introduced a multi-threading approach with the utilisation of Secure Hash Algorithm (SHA) to serve as a software based countermeasure to mitigate SCA attacks. The proposed countermeasure known as the FRIES noise generator executed as a Daemon and generated EM noise that was able to hide the cryptographic implementations and prevent the DEMA attack and other statistical analysis.
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Developing and testing the congruency of selected biological indicators and an existing tool designed to assess wetland health in agricultural settings in the KZN Midlands

  • Authors: Kubheka, Patrick Skhumbuzo
  • Date: 2018
  • Subjects: Wetland conservation -- South Africa -- KwaZulu-Natal , Wetland management -- South Africa -- KwaZulu-Natal , Wetland ecology -- South Africa -- KwaZulu-Natal , Ecosystem services -- South Africa -- KwaZulu-Natal , Environmental monitoring -- South Africa -- KwaZulu-Natal , Water quality biological assessment -- South Africa -- KwaZulu-Natal
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/58310 , vital:27211
  • Description: Despite the fact that wetlands have been understood to be important for a wide range of ecosystem services, wetlands continue to be degraded globally. There has been a growing need to develop biomonitoring tools that reflect the present ecological state of wetlands, but very few attempts have been made in South Africa to achieve this, and those that have attempted this have generally achieved limited success. This study was conducted to develop and test the congruency of four selected biological indicators (dragonflies, frogs, macroinveterbrates and plants) in relation to the assessment of present ecological state using an existing method in South Africa, "WET-Health". WET-Health assessments rely primarily on transformations to a wetland that result from human impacts in both the catchment and the wetland itself. Using the tool, a health score is obtained that is consistent with the Department of Water Affairs (DWA) current "present ecological state” as applied to river health assessment. The study was conducted in agricultural settings of the Midlands of KwaZulu-Natal based on 13 wetlands. The selected wetlands were scored using WET - Health and grouped in four different ecological condition classes (A, B, C and D). Physical characteristics (wetland area, mean depth), biological characteristics (species cover/abundance, presence and species richness), and chemical characteristics (ammonia, pH, sulphate, nitrogen and phosphate) were also recorded in the selected wetlands. Nineteen different species of dragonfly were recorded in this study. The study demonstrated that dragonflies are a promising bioindicator of wetland present ecological state as the dragonfly index was found to be closely correlated with WET- Health scores. Open water bodies within the selected wetlands were the focus of dragonfly sampling, as male dragonflies are territorial and they will patrol or be found around this habitat. Emergent vegetation dominated by sedges formed the focus of macroinvertebrate sampling in this study because greater numbers of macroinvertebrate families were found in this biotope in comparison to open water areas with no emergent vegetation. A total of 47 macroinvertebrate families were recorded in this study, but SASS5 scores based on macroinvetebrates showed no correlation with WET-Health scores. A total of 10 different frog species were recorded in this study. All the species were common frog species found in most parts of the country. Frog species richness and occurrence showed no correlation with WET- Health scores. A total of twenty samples of two meter radius were measured per wetland and sampled for plant species and estimation of cover-abundance of each species per sample. Over 50 different plant species were recorded in this study, and both species accumulation and species richness showed a degree of correlation with WET-Health scores. All the wetlands in class A had generally higher species accumulation rate and species richness compared to the other wetland classes. In addition to testing the congruency of four selected biological indicators with WET- Health, water quality was measured in all the wetlands. Wetlands in class A were associated with improved water quality as the water passes through the wetland. However, wetlands in class C and D did not show consistently improved water quality between the apex and the toe of these wetlands. In some cases the water quality deteriorated as it passed through wetlands in these two classes.
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Developing leadership and learner voice: a formative intervention in a Learner Representative Council in a Namibian secondary school

  • Authors: Haipa, Vistorina
  • Date: 2018
  • Subjects: School management and organization -- Namibia , Educational leadership -- Namibia , Education, Secondary -- Namibia , Student government -- Namibia , Student participation in administration -- Namibia , Student participation in administration -- Law and legislation -- Namibia , Cultural Historical Activity Theory
  • Language: English
  • Type: text , Thesis , Masters , MEd
  • Identifier: http://hdl.handle.net/10962/62188 , vital:28136
  • Description: Learner participation in leadership in Namibian schools was legislated in 2001 through the Namibian Education Act, No. 16 of 2001. This has then become a requirement for all secondary schools to establish a Learner Representative Council (LRC). However, this legislation only gives mandates to schools with grade 8-12. Despite the impetus of having a LRC in secondary schools, learner leadership and voice remains limited, given that we are 26 years into our democracy. This awakened my interest to conduct a study aimed at developing leadership and voice within the LRC in a Namibian secondary school. Additionally, this study was conducted to contribute to filling the gap in literature of Cultural Historical Activity Theory (CHAT) studies in the field of Education Leadership and Management. In this critical case orientation, the LRC were the subjects and the object of the activity was voice and leadership development within the LRC. I investigated participants’ perspectives on LRC leadership opportunities that existed in the case study school as well as factors that enabled and constrained leadership and voice development within the LRC of Omukumo (pseudonym) Secondary School in the northern part of Namibia. My study adopted a formative intervention design, using qualitative methodologies such as document analysis, observation, interviews, questionnaires and Change Laboratory Workshops. This study was framed by the second generation of CHAT. CHAT in this study was used as a methodological and analytical tool to surface the contradictions. Additionally, data were analysed by means of constructing categories and themes. Five sets of findings emerged: (1) a lack of conceptual awareness of the construct ‘learner leadership’: learner leadership was understood in terms of the LRC, (2) LRC members were not really acknowledged as equal participants in the school decision-making due to unequal power relations between the teachers and the LRC members, (3) misinterpretation of LRC policy that speak about the establishment of learners club and inadequate LRC training hindered the development of voice and leadership within the LRC, (4) the overall leadership role assigned to the LRC was to oversee the adherence of the school rules, and last (5) learner leadership and voice was still developing in the case study school. My key recommendation based on the research findings is the need for on-going LRC training at regional level; a need for large scale comparative studies between two African countries (Namibia, & South Africa) on the topic of learner leadership development and last, a need for workshops to train teachers on the implementation of national policies in schools, in particular those that speak to issues of learner voice and leadership.
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Development and assessment of a smart thermosetting intranasal hydrogel for lamotrigine

  • Authors: Melamane, Siyabonga
  • Date: 2018
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/62975 , vital:28349
  • Description: Expected release date-April 2020
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Development and assessment of gastroretentive sustained release captopril micro-balloons

  • Authors: Oridota, Omoyosola Omolola
  • Date: 2018
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/63491 , vital:28419
  • Description: Expected release date-April 2020
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Development and evaluation of a web application employing artificial neural networks to facilitate the prediction of antiretroviral drug resistance in patients infected with HIV-1 subtype B

  • Authors: Nabatanzi, Margaret
  • Date: 2018
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/63396 , vital:28406
  • Description: Expected release date-April 2019
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Development and optimisation of a novel Plasmodium falciparum Hsp90-Hop interaction assay

  • Authors: Wambua, Lynn
  • Date: 2018
  • Subjects: Plasmodium falciparum , Molecular chaperones , Heat shock proteins , Protein-protein interactions , Antimalarials
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/62626 , vital:28216
  • Description: Protein-protein interactions are involved in a range of disease processes and thus have become the focus of many drug discovery programs. Widespread drug resistance to all currently used antimalarial drugs drives the search for alternative drug targets with novel mechanisms of action that offer new therapeutic options. Molecular chaperones such as heat shock proteins facilitate protein folding, play a role in protein trafficking and prevent protein misfolding in cells under stress. Heat shock protein 90 (Hsp90) is a well-studied chaperone that has been the focus of cancer drug development with moderate success. In Plasmodium falciparum (P. falciparum), heat shock proteins are thought to play a vital role in parasite survival of the physiologically diverse habitats of the parasite lifecycle and because Hsp90 is prominently expressed in P. falciparum, the chaperone is considered a potentially ideal drug target. Hsp90 function in cells is regulated by interactions with co-chaperones, which includes Heat shock protein 70-Heat shock protein 90 organising protein (Hop). As opposed to directly inhibiting Hsp90 activity, targeting Hsp90 interaction with Hop has recently been suggested as an alternative method of Hsp90 inhibition that has not been explored in P. falciparum. The aim of this research project was to demonstrate PfHsp90 and PfHop robustly interact in vitro and to facilitate high-throughput screening of PfHsp90-PfHop inhibitors by developing and optimising a novel plate capture Hsp90-Hop interaction assay. To establish the assay, the respective domains of the proteins that mediate Hsp90-Hop interaction were used (Hsp90 C- terminal domain and Hop TPR2A domain). The human Hsp90 C-terminal domain and glutathione-S-transferase (GST) coding sequences were cloned into pET-28a(+) and murine and P. falciparum TPR2A sequences into pGEX-4T-1 plasmids to enable expression of histidine-tagged and GST fusion proteins, respectively, in Escherichia coli. The P. falciparum Hsp90 C-terminal domain sequence cloned into pET-28a(+) was supplied by GenScript. The constructs were transformed into T7 Express lysYcompetent E. coli cells and subsequent small- scale expression studies showed the recombinant proteins were expressed in a soluble form allowing for subsequent protein purification. Purification of the recombinant proteins was achieved using nickel-NTA and glutathione affinity chromatography for the His-tagged (Hsp90 C-terminal domains and GST) and GST fusion proteins (TPR2A domains), respectively. The purified proteins were used to establish and optimise mammalian and P. falciparum Hsp90- Hop interaction assays on nickel-coated plates by immobilising the His-tagged C-terminal domains on the plates and detecting the binding of the GST-TPR2A domains using a colorimetric GST enzyme assay. Z’-factor values above 0.5 were observed for both assays indicating good separation between the protein interaction signals and negative control background signals, although relatively high background signals were observed for the mammalian interaction due to non-specific binding of murine TPR2A to the plate. Designed human and P. falciparum TPR peptides were observed to be effective inhibitors of the mammalian and P. falciparum interactions, demonstrating the assay’s ability to respond to inhibitor compounds. Comparison of assay performance using GST assay kit reagents and lab- prepared reagents showed the assay was more efficient using lab-prepared reagents, however, lower GST signals were observed when comparing assay performance using a custom prepared Ni-NTA plate to a purchased Ni-NTA plate. The Hsp90-Hop interaction assays were also performed using an alternative assay format in which the GST-TPR2A fusion proteins were immobilised on glutathione-coated plates and binding of the His-tagged C-terminal domains detected with a nickel-horseradish peroxidase (HRP) conjugate and a colorimetric HRP substrate. The assay showed higher interaction signals for the P. falciparum proteins but comparatively low signals for the mammalian proteins. Z’-factor values for the assay were above 0.8 for both protein sets, suggesting this assay format is superior to the GST assay. However, further optimisation of this assay format is required. This study demonstrated direct binding of PfHsp90-PfHop in vitro and established a novel and robust PfHsp90-PfHop interaction assay format that can be used in future screening campaigns.
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Development and validation of a health literacy measure for limited literacy public sector patients in South Africa

  • Authors: Marimwe, Chipiwa
  • Date: 2018
  • Subjects: Health literacy -- South Africa , Patient education -- South Africa , Communication in medicine -- South Africa , Health literacy -- Social aspects -- South Africa , Poor -- Medical care -- South Africa , Analysis of variance , Multidimensional Screener of Functional Health Literacy (MSFHL)
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/62661 , vital:28227
  • Description: The growing complexity of healthcare demands greater patient involvement and skills to navigate this complex system. It has therefore become increasingly important to identify individuals with inadequate health literacy, by using efficient, short and reliable measures for doing so. Most research on the development and validation of health literacy tests has been conducted in high-income countries, with very little reported from low-and middle-income countries (LMICs). Existing health literacy measures have come under scrutiny for their lack of cultural sensitivity, bias towards certain population groups and failure to acknowledge health literacy as a multidimensional concept. These measures usually have limited application in LMICs due to the significantly different structuring of healthcare systems, they overlook the extreme discrepancies in educational levels, and rely too heavily on the ability to read health information. No health literacy data for South Africa are available, and only a few health literacy-based research papers have been published in this country. The aim of the study was to develop and validate a health literacy measure that is contextually and culturally appropriate to measure health literacy in limited literacy public sector patients in South Africa. An Item Bank of 30 questions was developed with the input of a diverse expert consultant panel, and included skills-based and self-reported questions which ensured cultural, contextual and educational level appropriateness. The Information and Support for Health Actions Questionnaire (ISHA-Q) is a health literacy measure developed to assess health literacy for LMICs which includes 14 core scales. These were useful in ensuring coverage of a range of health literacy constructs within the Item Bank. The 30 questions were then allocated to one of three health literacy domains: Procedural knowledge, Factual knowledge and Access to healthcare, health services and social support. Ethical approval for the study was obtained. The questions were translated into isiXhosa and underwent pilot testing. Following pilot testing, 120 isiXhosa first-language speakers, at least 18 years old, who attended public sector facilities and had a maximum 12 years of education were recruited from a primary healthcare clinic in Grahamstown. An interpreter was trained and he participated in all interviews. A questionnaire was used to collect data on the 30-question Item Bank. The Multidimensional Screener of Functional Health Literacy (MSFHL) was used as the primary comparator.The second phase of the study involved the refinement of the 30 questions in the Item Bank, which involved a multi-stage process. Data were analysed statistically using t-test, correlations, chi-square and ANOVA tests at a 5% level of significance, in order to identify problematic questions. Item Response Theory was used to ascertain difficulty and discriminatory ability of the questions. Each question was further subjected to in-depth interrogation by a panel of healthcare professionals to ensure that questions were supported by the conceptual framework and the definitions of health literacy adopted for this study. The number of questions was reduced from 30 to 12, and formed the new Health Literacy Test - Limited Literacy (HELT-LL). To validate the HELT-LL, 210 patients with the same inclusion criteria as previously noted, were recruited from four primary healthcare clinics in the Eastern Cape Province. Individual interviews were conducted with the assistance of the interpreter to collect sociodemographic data as well as data from the HELT-LL, the primary comparator (MSFHL), and a secondary comparator which was a South African modified version of the Newest Vital Sign (NVS-SA). The HELT-LL was re-administered to 40 patients in a follow-up interview two weeks later. The HELT-LL categorised only 17.6% of the patients as having adequate health literacy, just over a third with inadequate health literacy, and the majority with marginal health literacy. Questions in the cognitively demanding Procedural knowledge domain were the most poorly answered, with a mean score of 48.6±24.9%. Patients had great difficulty performing the basic numeric tasks in this domain. The overall mean score for the HELT-LL was 52.8±18.4%, compared with the more cognitively demanding NVS-SA with a mean of 28.6±21.1%, and clearly illustrated the impact of the strategy to include in the HELT-LL a variety of questions with differing cognitive load. The MSFHL, which is based on demographic characteristics and perceived difficulties with reading and writing, had an overall mean score of 44.4±26.2%. Demographic characteristics including age, education and English literacy, were found to be good predictors of limited health literacy, with significant correlations being found between these variables and the mean HELT-LL score. An acceptable value for Cronbach’s alpha, excellent test-retest reliability and excellent concurrent validity show that the HELT-LL is a valid and reliable measure of health literacy in our target population. As there is a paucity of health literacy research emanating from developing countries, this study presents a significant contribution to literature. It is the first study to report the development and validation of a health literacy measure to address the dearth of available health literacy measures applicable for South Africa. If implemented for use in clinical settings and for research purposes, it could provide valuable South African health literacy data which could inform the development of interventions focusing on improving health literacy and health outcomes.
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