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Nutrient supplementation and secondary metaolites in melanoma cells

  • Authors: Stoll, Karin Elisabeth
  • Date: 1994
  • Subjects: Vitamin C -- Therapeutic use Cancer -- Research
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:4049 , http://hdl.handle.net/10962/d1004110
  • Description: Considerable interest exists with regard to the putative therapeutic role of ascorbic acid in various conditions. A condition which has received much attention is cancer, as it is reported that ascorbic acid may be a prophylactic against cancer development. However, the actual involvement of ascorbic acid, an oxidizing/reducing agent, in the development and progression of tumours is presently a subject of much speculation. This study initially addressed the effect of ascorbic acid supplementation over a nutritional concentration range (0 - 100 μg/ml) on the in vitro growth of non-malignant LLCMK and malignant B16 cells. Ascorbic acid supplementation of these two cell types resulted in an overall decrease in the growth of both types of cells. The actual inhibitory mechanism of ascorbic acid on cell growth was not clear. Further study attempted to define and explain a mechanism responsible for this effect. Ascorbic acid has a role in the maintenance of tissue integrity and host defences, thus providing a rational basis for examining its relationship to cancer. Ascorbic acid is lcnown to be essential for the structural integrity of the intercellular matrix of the cells, the latter being a complex aqueous gel containing, amongst other compounds, fats and prostaglandins. Fats and prostaglandins have diverse effects on. membrane stability, enzyme activity and secondary messengers within cells. Hence, this study investigated the effect of ascorbic acid supplementation on certain enzymes and secondary metabolites within the cells, which had the potential to be involved in the control of cell growth. Throughout this study, emphasis was placed on the Bl6 melanoma cells as ascorbic acid supplementation did not significantly affect levels of secondary metabolites within the non-malignant LLCMK cells. Ascorbic acid supplementation of the B16 cells resulted in significant increases in adenylate cyclase activity and cyclic adenosine monophosphate levels, witb a significant decrease in Bl6 cell growth in that particular experiment. As cyclic adenosine monophosphate has a regulatory role in the cell cycle, this study suggested that the inhibitory effect of ascorbic acid supplementation on cell growth was mediated tbrough a final effect provided by the second messenger, cyclic adenosine monophosphate. However, clarification of tbe mechanism of tbe effect of ascorbic acid on adenylate cyclase activity was required. Hence, a further study investigated prostaglandin E₂ levels, as tbese affect adenylate cyclase activity. Prostaglandin E₂ levels were also found to be inversely related to Bl6 cell growth with ascorbic acid supplementation. It thus appeared tbat adenylate cyclase activity was dependent on prostaglandin E₂ levels in the B16 cells, and further study showed that tbis was indeed the case. Here, higher levels of prostaglandin E₂ supplementation of the Bl6 cells inhibited cell growth significantly and also significantly increased adenylate cyclase activity. Arachidonic acid is the precursor of prostaglandin E₂. In the presence of ascorbic acid supplementation, the percentage arachidonic acid composition of the Bl6 cells was inversely correlated with cell growth. Hence, prostaglandin E₂ levels in ascorbic acid supplemented B16 cells appeared dependent on tbe amount of precursor present. This was confirmed when Bl6 cells were supplemented with arachidonic acid. The latter had an inhibitory effect on Bl6 cell growth and also stimulated prostaglandin E₂ production. The cause of tbe inverse relationship between B16 cell growth and arachidonic acid composition with ascorbic acid supplementation was furtber investigated and found to be dependent on tbe uptake of arachidonic acid and other essential fatty acids from tbe medium. The enzymes phospholipase A₂ delta-5 and delta-6-desaturase, and elongase which could influence arachidonic acid levels were not affected to any extent by ascorbic acid supplementation and therefore did not influence the inverse relationship between B16 cell growth and arachidonic acid. Hence, it can be concluded that the effect of ascorbic acid supplementation on the BI6 cells is mediated, in part at least, by cyclic adenosine monophosphate. However, this is not the result of a direct effect of ascorbic acid supplementation. The initial effect of ascorbic acid supplementation concerns fatty acid - in particular arachidonic acid - uptake from the medium, with subsequent cascade effects On secondary metabolites, ultimately affecting the cellular levels of cyclic adenosine monophosphate.
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  • Date Issued: 1994

Exploring user-driven telephony services in an information and communication technology for development context

  • Authors: Kunjuzwa, Dumani Tau
  • Date: 2011
  • Subjects: Digital divide -- South Africa -- Eastern Cape , Information technology -- Social aspects -- South Africa -- Eastern Cape , Information technology -- Government policy -- South Africa -- Eastern Cape , Information society -- South Africa -- Eastern Cape , Telecommunication -- Social aspects -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , MSc (Computer Science)
  • Identifier: vital:11383 , http://hdl.handle.net/10353/546 , Digital divide -- South Africa -- Eastern Cape , Information technology -- Social aspects -- South Africa -- Eastern Cape , Information technology -- Government policy -- South Africa -- Eastern Cape , Information society -- South Africa -- Eastern Cape , Telecommunication -- Social aspects -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape
  • Description: There is a great difference that exists between people who have access to Information and Communication Technologies (ICTs) and those who do not. As a developing nation, South Africa is badly affected by the so-called Digital Divide. Information and Communication Technology for Development (ICTD) interventions are rapidly increasing in marginalized and rural communities in striving to bridge this digital divide. This research project is undertaken within the context of the Siyakhula Living Lab (SLL) which is an ICTD intervention at Dwesa rural community. This research investigates how audio-based services can be applied locally for communication and information sharing. This research aims to develop a user-driven telephony framework which will enable users to construct customized audio-based services. This aims to empower the Dwesa community for skill development and supports the user-driven innovation. The Internet and Telephones are the most popular technologies that are widely used in our daily life for purposes of communication and information access. Voice over Internet Protocol (VoIP) integrates these two separate technologies (Internet and Telephones) to produce real-time multimedia communication services such as Interactive Voice Response (IVR) systems. In addition, the ability of VoIP presenting information through voice plays a crucial role, more especially to those who do not have web visual access or those who are computer illiterate.
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  • Date Issued: 2011

A strategy to motivate continued instructor usage of learning management systems (LMSS) in higher learning institutions of Zimbabwe

  • Authors: Siwela, Ndukuyenkosi
  • Date: 2020
  • Subjects: Web-based instruction , Computer systems Organizational learning -- Zimbabwe Internet in education
  • Language: English
  • Type: Thesis , Masters , MPhil
  • Identifier: http://hdl.handle.net/10948/47259 , vital:39837
  • Description: The purpose of this study was to develop a strategy to motivate continued usage of Learning Management Systems in higher learning institutions of Zimbabwe. A related goal was to identify unique challenges experienced by instructors in their use of LMSs. The use of LMSs is now global and has been fairly successful in developed countries even though past research shows that instructors tend to discontinue usage over a period of time. Whereas most LMSs research is carried in the context of the developed world, the candidate demonstrates that Vantankesh's IS Success Model and Davis' Technology Acceptance Model can be successfully replicated into the developing world on condition that local environment is taken into context. The results showed that LMSs in Zimbabwe higher learning institutions hold a promise of success even though challenges exist. The findings have wider implications on the need to invest in neccessary infrustructure and future predictions on learner interests. The study demonstrates that shared success can be achieved if the local conditions are taken into context when developing a strategy to motivate instructor continued LMS usage. The study holds the practical implication that institutions can motivate instructors to continue with usage of LMSs to deliver quality output in their daily duties.
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  • Date Issued: 2020

Material Chemistry 1: PAC 227

  • Authors: Zulu, N H , Ajibade, P A
  • Date: 2012-01
  • Language: English
  • Type: Examination paper
  • Identifier: vital:17821 , http://hdl.handle.net/10353/d1010374
  • Description: Material Chemistry 1: PAC 227, supplementary examination January 2012.
  • Full Text: false
  • Date Issued: 2012-01

Fluorescence “turn on” probe for bromide ion using nanoconjugates of glutathione-capped CdTe@ ZnS quantum dots with nickel tetraamino-phthalocyanine

  • Authors: Adegoke, Oluwasesan , Nyokong, Tebello
  • Date: 2013
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/190479 , vital:44998 , xlink:href="https://doi.org/10.1016/j.jphotochem.2013.05.013"
  • Description: In this paper, three differently sized glutathione (GSH)-capped CdTe@ZnS quantum dots (QDs) have been successfully conjugated to nickel tetraamino-phthalocyanine (NiTAPc) to form different QDs-NiTAPc nanocomplexes. Several techniques such as TEM, FT-IR, time-resolved fluorescence measurement and electronic spectroscopy were employed to characterize the nanocomplex. Bromide ion was chosen as a model anion to test the efficacy of the nanoprobe. The fluorescence of the nanoconjugate was “turned off” upon binding but was progressively “turned on” upon interaction with varying concentrations of bromide ion. Experimental results showed that the quantum size effect of nanocrystal QD determined the overall sensitivity and selectivity of the nanoprobe and followed the order QD563-NiTAPc > QD605-NiTAPc > QD621-NiTAPc. The mechanism of reaction is proposed.
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  • Date Issued: 2013

Quantifying crop damage by Grey crowned crane balearica regulorum regulorum and evaluating changes in crane distribution in the North Eastern Cape, South Africa

  • Authors: Van Niekerk, Mark Harry
  • Date: 2011
  • Subjects: Cranes (Birds) -- South Africa -- Eastern Cape , Cranes (Birds) -- Geographical distribution -- South Africa -- Eastern Cape , Cranes (Birds) -- Behavior -- South Africa -- Eastern Cape , Cranes (Birds) -- Food -- South Africa -- Eastern Cape , Corn -- Effect of grazing on -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5749 , http://hdl.handle.net/10962/d1005436 , Cranes (Birds) -- South Africa -- Eastern Cape , Cranes (Birds) -- Geographical distribution -- South Africa -- Eastern Cape , Cranes (Birds) -- Behavior -- South Africa -- Eastern Cape , Cranes (Birds) -- Food -- South Africa -- Eastern Cape , Corn -- Effect of grazing on -- South Africa -- Eastern Cape
  • Description: Complaints of crop damage by cranes on planted maize in the North Eastern Cape, South Africa, have been increasing since the mid-1990‘s, and in some instances severe losses have been reported. Crop damage by the Grey Crowned Crane Balearica regulorum regulorum near the town of Maclear (31º04´S 28º22´E), has been quantified over two growing seasons, and assessed relative to losses caused by foraging Cape Crows Corvus capensis and other feeding damage assumed to be caused by insects. Twelve fields were selected based on previous patterns of crop depredation. Maize seed in seven of the fields was treated with the chemical ‗Gaucho‘ and five fields were planted with untreated maize. In order to determine the source of losses, twenty quadrats (4 m x 4 m) randomly distributed within each field were visited on average every second day, for a period of up to twenty eight days. Results indicate that seed treatments do act as a deterrent to feeding by both cranes and crows, however crane damage is generally insignificant compared to other sources of damage. My study also reviewed past sightings data of the Grey Crowned Crane in an effort to determine if the conversion of former grassland to plantations in this region may have increased foraging activity in maize fields. The data did not allow for clear-cut conclusions regarding changes in distribution or population trends. Conclusions provide direct input into the management of agricultural areas by enabling landowners to take steps to mitigate crop damage. These mitigation measures may either involve the application of seed treatments, or the planting of low risk crops in high risk areas. Future studies should consider the ppossible detrimental effects of chemical seed treatments on crane biology.
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  • Date Issued: 2011

Negotiating identity in an online virtual environment

  • Authors: Dube, Nompumelelo
  • Date: 2011-11
  • Subjects: Online Identities , Internet , Personal Information Managenment
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10353/23883 , vital:61284
  • Description: This study investigates ways in which people in an online anonymous virtual environment use language to negotiate and manage their identities. The study is informed by the tenets of social constructionism, a theory that explores the problematic manner in which the self is taken for granted as unchanging (Burr, 1998). One point made by alternative theorists other than social constructionist theorists is the notion of the “essential self”; one tenet of social constructionist theory suggests that the “essential self” of a person remains fluid. The implication is that one ultimately changes as each day passes, for example at the core of one’s personality is an “essential self” that changes with experiences, conflicts and/or age (Tuffin, 2005). From a social constructionist perspective, the self is more fractured and contingent on life’s circumstances. This theory was found to be an appropriate paradigm from which to study anonymous online identities, where individuals were found to create and negotiate certain identities outside of those identities that people often find important to portray to outsiders in the general public. Sixty-seven (67) students from different races participated in this study and online discussions from a course discussion forum, “blackboard”, were monitored. This study found that one’s identity is negotiated in an anonymous virtual environment. Data was collected from these discussions and was analysed using Potter and Wetherell’s (1987) method of discourse analysis. Research findings ultimately found that people use discursive strategies in negotiating and maintaining their identity online, but that distinct racial characteristics were noticeable despite some attempts to mask one’s background. , Thesis (MA) -- Faculty of Social Sciences and Humanities, 2011
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  • Date Issued: 2011-11

The relationship between employee value proposition, organisational commitment and intention-to-serve among provincial traffic officers

  • Authors: Macpherson, Wayne Elvison
  • Date: 2017
  • Subjects: Organizational commitment -- South Africa -- Eastern Cape Organizational behavior -- South Africa -- Eastern Cape , Employee motivation -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10948/18036 , vital:28567
  • Description: Traffic officers are employed to protect and serve the community, but various sources including annual reports and newspaper articles cast doubt on whether these goals are attained in the Eastern Cape. These sources further allege that the failure to serve can be attributed to dissatisfaction and poor employee commitment. Therefore, the main objective of this study was to explore the relationship between the Employee Value Proposition, organisational commitment and intention-to-serve among provincial traffic officers. A literature study was conducted on the three above-mentioned variables to achieve this objective. The empirical study consisted of a survey with a self-administered questionnaire. Five components of the Employee Value Proposition, as established by the Corporate Leadership Council (CLC) (2006), were measured. These included career opportunities, organisation itself, relationships, remuneration/reward and work itself. The Three Component Model (TCM) developed by Meyer and Allen (1991) was used to measure affective, continuance and normative commitment. The Intention-to-Serve Scale was adapted from the Employee Work Passion Appraisal (EWPA) Model (Zigarmi, Nimon, Houson, Witt and Diehl, 2011) and was used to measure intent-to-perform and intent-to-use discretion. The questionnaire was completed by 357 provincial traffic officers across the six districts of the Eastern Cape, which represented a 95 percent response rate. The results from the empirical study indicated that the majority of respondents had less positive perceptions of the Employee Value Proposition offered to them. Affective commitment, regarded as the desired type of organisational commitment, was scored the lowest. However, positive scores were obtained for intention-to-serve. A statistical and practical significant relationship was found between the Employee Value Proposition and organisational commitment, and between the Employee Value Proposition and intention-to-serve as well as between organizational commitment and intention-to-serve. The results suggest that a more appealing Employee Value Proposition could result in improved organisational commitment as well as improved intention-to-serve. It is therefore recommended that the Eastern Cape Department of Transport reconsider the Employee Value Proposition offered to traffic officers and use it as a tool to improve commitment and service delivery.
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  • Date Issued: 2017

Exploring the suitability of the evaluation criteria used in the MPT projects, by looking at hard and soft components of development programmes

  • Authors: Ncapai, Wandile
  • Date: 2002
  • Subjects: Community development -- South Africa -- Eastern Cape , Community development , Economic development -- South Africa -- Eastern Cape , Economic development projects -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , MSocSc
  • Identifier: vital:3397 , http://hdl.handle.net/10962/d1018255
  • Description: The study explores the suitability of the evaluation criteria used in Microprojects Programme Trust (MPT), by looking at hard and soft components of the development programme. In this sense hard components of development refer to those components of projects that are tangible and can be physically observed and can bring material changes to the life of the community. Soft components of development refer to those components of projects that bring qualitative transformation to the life of the community, i.e. increased levels of awareness, human well-being and the empowerment process that addresses the community's abstract needs, these are not tangible and often cannot be physically observed. Midway through its contract periods MPT evaluate all projects. The purpose of these mid term evaluations is to make recommendations to MPT on future approaches and methodology for community development and operations. The mid-term evaluation also influences the distribution and allocation of resources and funding. It was therefore vital that the criteria used are subject to tests and critical analysis so as to assess their validity. The assessment of the mid-term evaluation criteria used in MPT projects has been to further determine the appropriateness or suitability of the evaluation criteria as an instrument to measure and guide the MPT community development approach in the Eastern Cape. The method used was to conduct focus group discussions so as to get an insight into the local community situation as well as to assess non-tangible improvements and changes that have occurred in the life of the community as a result of the project. The information generated was used to compare what the community believe they achieved with what the official mid-term evaluation reports indicate was assessed and achieved and that was contrasted with what the literature recommends should have been assessed. The study found that the mid-term evaluations conducted on MPT projects have no social context in which the evaluations themselves were conducted. The terms of reference and criteria were based on the programme design which was formulated and compiled by the European Union without the participation of the local South African community. The findings also indicated that projects become unsuccessful or partly successful if the "soft" components which have a bearing on social and economic realities are neglected. The thesis ends with recommendations on how the mid-term evaluations as well as MPT programme can be developed to be more responsive to the needs as identified by the communities themselves. It is strongly believed that this study will provide a valuable contribution towards increasing the ability of MPT programme to bring about both material and qualitative transformation to the I ives of the disadvantaged community of the Eastern Cape whilst ensuring that the mid-term evaluations are developed and shaped to become an appropriate instrument to measure and guide MPT programme approach to community development.
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  • Date Issued: 2002

The WTO agreement on technical barriers to trade : a critical appraisal of its implementation within the Southern African Development Community

  • Authors: Chimeri, Vongai
  • Date: 2017
  • Subjects: Tariff -- Law and legislation Non-tariff trade barriers -- Law and legislation Foreign trade regulation
  • Language: English
  • Type: Thesis , Masters , LLM
  • Identifier: http://hdl.handle.net/10353/2855 , vital:28108
  • Description: The World Trade Organisation Agreement on Technical Barriers to Trade (TBT Agreement) was crafted with the aim of ensuring that technical regulations, standards and conformity assessment procedure do not constitute unnecessary obstacles to international trade. Southern African Development Community (SADC) countries have since ratified this Agreement and took a step further to incorporate its principles into the Technical Barriers to Trade Annex to the SADC Protocol on Trade. Despite this effort, SADC countries are still grappling with implementing the TBT Agreement in their domestic frameworks. Consequently, technical barriers to trade have become impediments to both regional and international trade. It is in this context that this study aims to examine the implementation of the TBT Agreement within the SADC. The study answers the question what are the challenges facing SADC Member states to fully implement the TBT Agreement? The study demonstrates that SADC Member face challenges which include of lack adequate resources, technical expertise and enforcement mechanisms to effectively implement the TBT Agreement. In the finality, the study recommends SADC Member states to deepen regional integration in order to collaborate on matters relating to technical barriers to trade within the region. Member states should also share information and learn from the experiences of other countries on how to effectively implement the TBT Agreement. Further, government officials should be educated on trade-friendly regulations that do not compromise on the principles of the TBT Agreement. To this end, regulatory impact assessments should be established in order to assess the trade effects of both new and old regulations. Effective enforcement mechanisms should also be introduced in order to coerce Member states to comply with their regional obligations. By effecting these recommendations, SADC states have the opportunity to eradicate technical barriers to trade thereby increasing both regional and international trade.
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  • Date Issued: 2017

A study of the Presbyterian Church mission in the Transvaal from 1903-1960

  • Authors: Boyd, Barry Graeme
  • Date: 1981 , 2013-03-22
  • Subjects: Presbyterian Church -- South Africa -- Transvaal , Missions -- South Africa -- Transvaal
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:1226 , http://hdl.handle.net/10962/d1006110 , Presbyterian Church -- South Africa -- Transvaal , Missions -- South Africa -- Transvaal
  • Description: The aim of ·this study is to present a picture of the circumstances and the manner in which the mission was undertaken. With this in mind reference has been made to individual men and their particular importance and also to the decislons of the Church Assembly as they affected Mission. In part, the thesis is fuller for the earlier years, for the writer holds that these were the most formative as they established the pattern. Furthormore the writer wishes to make clear that the Mission become the work of black men with the white Mission Secretary of the 1950's filling an administrative role. This does not mean he was unimportant but for the nature of this study and its desire to ·emphasise the role of the black man, the work of these individual administrators has been largely omitted. In the concluding chapters the writer has shown the effects of political changes and African Nationalism on the Mission with a further chapter on the Mission's educational work. , KMBT_363 , Adobe Acrobat 9.53 Paper Capture Plug-in
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  • Date Issued: 1981

Zoology: ZOO 222

  • Authors: Okeyo, D O , Vumazonke, L , Madikiza, Z
  • Date: 2010-11
  • Language: English
  • Type: Examination paper
  • Identifier: vital:17790 , http://hdl.handle.net/10353/d1010330
  • Description: Zoology: ZOO 222, semester examination November 2010.
  • Full Text: false
  • Date Issued: 2010-11

Technology in conservation: towards a system for in-field drone detection of invasive vegetation

  • Authors: James, Katherine Margaret Frances
  • Date: 2020
  • Subjects: Drone aircraft in remote sensing , Neural networks (Computer science) , Drone aircraft in remote sensing -- Case studies , Machine learning , Computer vision , Environmental monitoring -- Remote sensing , Invasive plants -- Monitoring
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/143408 , vital:38244
  • Description: Remote sensing can assist in monitoring the spread of invasive vegetation. The adoption of camera-carrying unmanned aerial vehicles, commonly referred to as drones, as remote sensing tools has yielded images of higher spatial resolution than traditional techniques. Drones also have the potential to interact with the environment through the delivery of bio-control or herbicide, as seen with their adoption in precision agriculture. Unlike in agricultural applications, however, invasive plants do not have a predictable position relative to each other within the environment. To facilitate the adoption of drones as an environmental monitoring and management tool, drones need to be able to intelligently distinguish between invasive and non-invasive vegetation on the fly. In this thesis, we present the augmentation of a commercially available drone with a deep machine learning model to investigate the viability of differentiating between an invasive shrub and other vegetation. As a case study, this was applied to the shrub genus Hakea, originating in Australia and invasive in several countries including South Africa. However, for this research, the methodology is important, rather than the chosen target plant. A dataset was collected using the available drone and manually annotated to facilitate the supervised training of the model. Two approaches were explored, namely, classification and semantic segmentation. For each of these, several models were trained and evaluated to find the optimal one. The chosen model was then interfaced with the drone via an Android application on a mobile device and its performance was preliminarily evaluated in the field. Based on these findings, refinements were made and thereafter a thorough field evaluation was performed to determine the best conditions for model operation. Results from the classification task show that deep learning models are capable of distinguishing between target and other shrubs in ideal candidate windows. However, classification in this manner is restricted by the proposal of such candidate windows. End-to-end image segmentation using deep learning overcomes this problem, classifying the image in a pixel-wise manner. Furthermore, the use of appropriate loss functions was found to improve model performance. Field tests show that illumination and shadow pose challenges to the model, but that good recall can be achieved when the conditions are ideal. False positive detection remains an issue that could be improved. This approach shows the potential for drones as an environmental monitoring and management tool when coupled with deep machine learning techniques and outlines potential problems that may be encountered.
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  • Date Issued: 2020

Reactivity of Rhenium (iii) and Rhenium (V) with multidentate NN-and no-donor ligands

  • Authors: Yumata, Nonzaliseko Christine
  • Date: 2010
  • Subjects: Rhenium , Ligands
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:10373 , http://hdl.handle.net/10948/1085 , Rhenium , Ligands
  • Description: The reaction of the potentially tridentate Schiff-base chelate Hhaep [Haep = N’-(1- (2-hydroxyphenyl)ethylidene)benzohydrazide] with [ReCl3(benzil)(PPh3)] and trans-[ReOCl3(PPh3)2] produced the neutral oxorhenium(V) complexes cis- [ReOCl2(mep)] [Hmep = 2-(1-iminoethyl)phenol] and cis-[ReOCI2(meb)(PPh3)] [Hmeb = N’-(propan-2-ylidene)benzohydrazide] in ethanol and acetone respectively. In both reactions the Hhaep molecule cleaves to give different coordinated bidentate NO-donor chelates coordinated to the rhenium(V) centers. The X-ray studies reveal that mep is present as a bidentate, monoanionic Schiffbase coordinating through the neutral imino nitrogen and the deprotonated phenolate oxygen in cis-[ReOCl2(mep)]. The bond distances and angles in cis- [ReOCI2(meb)(PPh3)] confirm that meb coordinates to the metal in the enolate form. The distorted octahedral complex fac-[ReCl3(dpa)(PPh3)] was prepared by the reaction of trans-[ReCl3(MeCN)(PPh3)2] with a twofold molar excess of dpa in acetonitrile under a nitrogen atmosphere. The compound dpa.HCl.2H2O was obtained as a by-product in the reaction of dpa with trans-[ReCI3(MeCN)(PPh3)2] in acetonitrile. The reaction of trans-[ReCl3(MeCN)(PPh3)2] with a twofold molar excess of 6- amino-3-methyl-1-phenyl-4-azahept-2-ene-1-one (Hamp) in acetonitrile led to the isolation of cis-[ReCl2(bat)(PPh3)2]. On complexation to the metal center Hamp decomposed to give the coordinated benzoylacetone (bat). Bat is present as a monoanionic bidentate chelate. The complexes [ReVOCI(had)] and [ReIVCl(had)(PPh3)](ReO4) were prepared from the reaction of trans-[ReCl3(MeCN)(PPh3)2] with N,N-bis((2-hydroxybenzyl)-2- aminoethyl)dimethylamine (H2had) in ethanol under various reaction conditions. The treatment of [ReCl3(benzil)(PPh3)] with 2-[((2- pyridinylmethyl)amino)methyl]phenol (Hham) in a 2:1 molar ratio in acetonitrile led to the isolation of the hydrogen-bonded dimer [ReOCl2(ham)]2. The distorted octahedral complex [ReOCl(hap)] [H2hap = N,N-bis(2- hydroxybenzyl)aminomethylpyridine] was prepared from the reaction of trans- [ReCl3(MeCN)(PPh3)2] with a twofold molar excess of H2hap in acetonitrile. The X-ray crystal structure analysis shows that the chloride is coordinated trans to the tripodal tertiary amino nitrogen, with a phenolate oxygen trans to the oxo oxygen.
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  • Date Issued: 2010

Rhodeo, Vol. 19, No. 19

  • Subjects: Grahamstown -- Newspapers , Journalism, Students -- South Africa , Rhodes University -- Activate , Rhodes University -- Students , Student newspapers and periodicals -- South Africa
  • Language: English
  • Type: Text
  • Identifier: vital:14534 , http://hdl.handle.net/10962/d1019406
  • Description: Rhodeo is the Independent Student Newspaper of Rhodes University. Located in Grahamstown, Rhodeo was established in 1947, and renamed in 1994 as Activate. During apartheid Rhodeo became an active part of the struggle for freedom of expression as part of the now defunct South African Student Press Union. Currently Activate is committed to informing Rhodes University students, staff and community members about relevant issues, mainly on campus. These issues range from hard news to more creative journalism. While Activate acts as a news source, one of its main objectives it to be accessible as a training ground for student journalists. The newspaper is run entirely by the students and is published twice a term. Activate is a free newspaper which receives an annual grant from the Rhodes University Student Representative Council, however, majority of its revenue is generated through advertising.
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A framework proposal for algorithm animation systems

  • Authors: Yeh, Chih Lung
  • Date: 2006
  • Subjects: Computer programming , Computer algorithms , Computer graphics
  • Language: English
  • Type: Thesis , Masters , MCom
  • Identifier: vital:10488 , http://hdl.handle.net/10948/d1019680
  • Description: The learning and analysis of algorithms and algorithm concepts are challenging to students due to the abstract and conceptual nature of algorithms. Algorithm animation is a form of technological support tool which encourages algorithm comprehension by visualising algorithms in execution. Algorithm animation can potentially be utilised to support students while learning algorithms. Despite widespread acknowledgement for the usefulness of algorithm animation in algorithm courses at tertiary institutions, no recognised framework exists upon which algorithm animation systems can be effectively modelled. This dissertation consequently focuses on the design of an extensible algorithm animation framework to support the generation of interactive algorithm animations. A literature and extant system review forms the basis for the framework design process. The result of the review is a list of requirements for a pedagogically effective algorithm animation system. The proposed framework supports the pedagogic requirements by utilising an independent layer structure to support the generation and display of algorithm animations. The effectiveness of the framework is evaluated through the implementation of a prototype algorithm animation system using sorting algorithms as a case study. This dissertation is successful in proposing a framework to support the development of algorithm animations. The prototype developed will enable the integration of algorithm animations into the Nelson Mandela Metropolitan University’s teaching model, thereby permitting the university to conduct future research relating to the usefulness of algorithm animation in algorithm courses.
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  • Date Issued: 2006

Adherence and non-adherence to antiretroviral treatment in HIV people in Port Elizabeth

  • Authors: Masokoane, Kgomotso Quentinne
  • Date: 2009
  • Subjects: Antiretroviral agents -- South Africa -- Port Elizabeth , HIV infections -- Treatment -- South Africa -- Port Elizabeth , AIDS (Disease) -- Treatment -- South Africa -- Port Elizabeth
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:9886 , http://hdl.handle.net/10948/1185 , Antiretroviral agents -- South Africa -- Port Elizabeth , HIV infections -- Treatment -- South Africa -- Port Elizabeth , AIDS (Disease) -- Treatment -- South Africa -- Port Elizabeth
  • Description: The introduction of antiretroviral drugs (ARVs) in 1996 transformed the treatment of HIV and AIDS, improving the quality and greatly prolonging the lives of many infected people. HIV (Human Immunodeficiency Virus) is the virus that is believed to cause AIDS. AIDS (Acquired Immune Deficiency Syndrome) is the collection of illnesses or symptoms that ultimately results in death. Antiretroviral (ARVs) drugs or Highly Active Antiretroviral Therapy (HAART) is the treatment that has been applied to combat the HI virus in a bid to slow down the progression of AIDS and ultimately prolong the life of the infected individual. The study aimed to explore and describe the factors contributing to adherence and non-adherence to ARVs in individuals on treatment. A sample of 81 individuals who have been on ARV and HAART treatment for six months or more was used. The methodology used was exploratory-descriptive and the data obtained was quantitative in nature. A biographical questionnaire and questionnaire with questions aimed at ascertaining the possible factors that contribute to individuals either adhering to or defaulting on their treatment, such as side effects and cost of treatment, was administered. The data obtained was analysed by means of descriptive statistics and frequency counts. The results of the study showed that the sample had a fairly high level of adherence. The factors that could undermine adherence were identified as lack of support, as familial and health provider support acts as a motivator to adhere; substance abuse as it can lead to forgetting to take treatment; unemployment and poverty, as these can lead to an inability to return for follow up clinic visits or failure to have food to take with the pills; and the type of treatment regimen whereby the more complex the treatment is the more likely it is that adherence will be difficult to maintain. Suggestions were made as to future research involving antiretroviral therapy (ART). Finally the limitations as well as the value of the research were outlined.
  • Full Text:
  • Date Issued: 2009

An exploration of spirit possession and psychological praxis in South Africa: implications for a culturally competent psychological practice

  • Authors: Yew-Siong, Lauren Cindy
  • Date: 2021-04
  • Subjects: Spirit possession -- South Africa -- Psychological aspects , Cultural competence -- South Africa -- Psychological aspects
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10948/52394 , vital:43635
  • Description: Spirit possession has been documented in human history and evidence of it, still exists globally. In South Africa, spirit possession experiences are not uncommon; in some instances, culturally, they can be expressed as ‘amafufunyana’, while religiously, the term demonic/spirit possession holds true. The symptoms of a spirit possession state, should be of interest to psychology, given the similarity of its symptoms with those that are often typical of a psychological diagnosis, such as dissociation, hallucinations and delusions. While much attention has been given to patient experiences of spirit possession, little attention has been focused on the cultural competence required in working with patients with diverse worldviews. This study explores psychologists perceived cultural competence in working with patients who present with the experience of being possessed by a spirit. This exploration becomes more interesting, given that little to no attention in the literature has focused on the role and influence of psychologists religious and cultural belief systems and how these may influence (if at all), the understanding, diagnosis and treatment of a patient who believes that they are possessed. The researcher employed a qualitative method and design. Participants were recruited through use of a purposive sampling technique. Twelve psychologists agreed to participate in the study and thematic analysis was used to analyze the data, by following a data analysis method by Braun and Clarke (2006). Four themes were identified namely, 1) Psychologists’ understanding and treatment of dissociative disorders/states, 2) Psychologists’ understanding of spirit possession; 3) Spirit possession experiences versus psychological disturbances; and 4) Cultural acknowledgement versus cultural considerations-implications for cultural competence. Findings from the study suggest that it is not only cultural considerations that is Running Head: An Exploration of Spirit Possession and Psychological Praxis in South Africa: Implications for a Culturally Competent Psychological Practice. xv needed within psychological practice, but that a sense of cultural acknowledgement is needed in order to bring about potential holistic healing, and more specifically, aid cultural competence within psychological practice. This, according to the findings of the study, can be done through collaboration between various professionals or practitioners- furthermore creating a platform for the inclusion of pluralism within mental healthcare services. , Thesis (MA) -- Faculty of Health Sciences, 2021
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  • Date Issued: 2021-04

An investigation of how enquiry-based fieldwork develops action competence in Grade 12 Geography: a Namibian case study

  • Authors: Simasiku, Frederick
  • Date: 2012
  • Subjects: Competency-based education -- Namibia -- Hardap Geography -- Study and teaching (Secondary) -- Namibia -- Hardap Student-centered learning -- Namibia -- Hardap Active learning -- Namibia -- Hardap Environmental education -- Namibia -- Hardap Environmental education -- Activity programs -- Namibia -- Hardap
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1629 , http://hdl.handle.net/10962/d1003511
  • Description: The goal of the study was twofold: firstly to investigate and describe how senior secondary school geography teachers were implementing enquiry-based learning through fieldwork. Secondly, to investigate and document how enquiry-based learning through fieldwork facilitated the development of action competence amongst learners in a geography classroom. In order to address the first goal, a survey questionnaire was utilised to generate descriptive data from a sample of seven geography teachers in the Hardap region of Namibia. Although teachers engaged learners with enquiry-based fieldwork learning activities it is suggested, based on the findings of data of this goal, that teachers face severe limitations in terms of integrating environmental learning into the geography curriculum. The main limitations of the teachers include: limited practical knowledge of and training in how to teach fieldwork skills; a lack of teaching resource materials; time constraints; heavy personal loads; and lack of school support for environmental education. In addressing the second goal an enquiry-based fieldwork learning unit was planned and implemented in the researcher’s classroom. Observation, focus group interviews, and audio records of learning interactions, were used as data generation methods for this cycle of the study. An indicator framework for identifying action competence in learners was constructed as a data analysis tool. In terms of the findings of goal two it is evident that enquiry-based learning through fieldwork facilitated the development of action competence amongst learners. Six overarching benefits of this type of learning were identified in this study, namely: - It empowered learners to develop contextual knowledge and understanding of issues that they investigated. - It facilitated commitment thus motivated learners to take indirect action. - It promoted social interaction and group cohesion amongst learners thus enhanced their decision-making ability for problem-solving and action taking. - It elicited emotional responses and a greater understanding of learners’ own and others’ attitudes and values towards issues. - It fostered critical thinking thus permitted learners to envisage a future based on their learning experiences. - It enabled learners to plan and take indirect action during the learning process. Based on the research findings, some lessons learned are presented in an attempt to contribute to the effective implementation of enquiry-based fieldwork at the classroom level.
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  • Date Issued: 2012

Analysis of the existence of the Phillips curve, Okun’s law and Taylor rule in the Zambian economy

  • Authors: Chella, Siame Nampasa
  • Date: 2020
  • Subjects: Unemployment -- Effect of inflation -- Mathematical models --Zambia
  • Language: English
  • Type: Thesis , Masters , MCom
  • Identifier: http://hdl.handle.net/10948/49783 , vital:41800
  • Description: The objective for this study was to explore the relationship between inflation and growth with an understanding of the effects of unemployment on growth. The primary objective of this paper was to investigate the existence of Phillips Curve, Okun’s Law, and Taylor Rule in Zambia on the basis that Zambia is a youthful economy, with a growing population, which is expected to temper with unemployment rates, as an increase in the supply of labour might be too high for the demand for jobs available. To be specific, the study aims at determining the relationship between inflation and growth and seeks to understand what policy measures have been undertaken to curb inflation and reduce unemployment in Zambia. To achieve this, a quantitative research was undertaken using the ARDL cointegration model in conjunction with sensitivity tests to cater for structural changes in the economy with 2007 standing as the break point, as well as paying attention to the fact that different policy regimes employed during the course of the data covered, that being, 1996 to 2017, would affect that rates of unemployment, inflation and growth of the country, across period under review. The study revealed that Zambia faces a Hybrid New Keynesian Phillips Curve during the period under study which is dominated by a mixture of both back-ward and forward-looking aspects of inflation. This specifically, paints the effects of inflation persistence as well future expectations of inflation on growth. Further, a cointegration relationship was established between unemployment and output, while Taylor principles were found not to apply to the Zambian economy, which have proved in other economies to be foundation blocks for good economic growth and as such significant to both fiscal and monetary policy authorities of the economy. The researcher therefore recommends that Zambian policy makers, that is, both the fiscal and the monetary authorities, work together in order to attain minimal and optimal levels of inflation to help achieve a conducive economic environment for the country.
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  • Date Issued: 2020
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