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A Review of Arterial Stiffness and HIV Infection in Adult Africans

  • Authors: Awotedu, Kofoworola Olajire , Iputo, Jehu
  • Date: 09-06-2016
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/11260/3484 , vital:43615 , https://www.hilarispublisher.com/open-access/a-review-of-arterial-stiffness-and-hiv-infection-in-adult-africans-2167-1095-1000221.pdf
  • Description: Aim: To review the impact of the human immunodeficiency virus and antiretroviral therapy on the vasculature. Objectives: This review seeks to identify the burden which the human immunodeficiency virus and antiretroviral therapy have on the vasculature. Method: Medline/PubMed and Google scholar were searched. There were over 100 publications reviewed. Some people who worked in similar fields were also contacted. The present review summarized current understanding of Human immunodeficiency virus, antiretroviral therapy and effect on the vasculature such as arterial stiffness. Atherosclerosis, endothelial dysfunction, the strengths and weaknesses of current testing strategies, and their potential applications in clinical research and patient care. The association of inflammatory biomarkers, blood pressure and ageing with arterial stiffness were also reviewed. Conclusion: Available literature shows that HIV and antiretroviral agents have a great impact on the vasculature and its progression.
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  • Date Issued: 09-06-2016

Playing broken telephone with student feedback: the possibilities and issues of transformation within a South African case of a collegial rationality model of evaluation

  • Authors: Belluigi, Dina Z
  • Date: 2013
  • Language: English
  • Type: text , book
  • Identifier: http://hdl.handle.net/10962/66943 , vital:29003 , https://doi.org/10.1016/B978-1-84334-655-5.50001-5
  • Description: publisher version , Drawing on the case of a small South African university which espouses a social justice approach to transformation, this chapter considers the possibilities and challenges created for student feedback within an institutional context that gives the individual lecturer a large degree of autonomy in evaluation. The chapter looks at some of the dominant perceptions of student feedback in addition to how it is collected and utilised, by referring to the institution’s policies and guideline documents; institutional research conducted with course coordinators; responses elicited from 40 lecturers on the issues outlined in this chapter; the author’s own reflections as a staff developer in the institution; and specific examples of good practice from lecturers situated within social science disciplines. The emerging concerns which structured this discussion are: the impact of student feedback on improving quality; enabling student voice; increasing student ownership; and the educational value of evaluation processes.
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  • Date Issued: 2013

Utilizing gesture recognition and Ethernet AVB for distributed surround sound control

  • Authors: Hedges, Mitchell , Foss, Richard
  • Date: 2014
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/426816 , vital:72393 , https://www.aes.org/e-lib/online/browse.cfm?elib=17540
  • Description: Gesture recognition has become a preferred approach to the control of various systems. This allows users of the system to interact without having to use any controls or equipment. This paper investigates the use of gesture recognition in order to select and transport audio tracks over an Ethernet AVB network to speaker endpoints. The research uses equipment that is commercially available and relatively cost efficient. The endpoints receive audio samples that are encapsulated within network packets and processes them. The audio tracks are mixed at the endpoints according to gain ratios that will change and be different for each endpoint.
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  • Date Issued: 2014

'Meaningful engagement’: Towards a language rights paradigm for effective language policy implementation

  • Authors: Docrat, Zakeera , Kaschula, Russell H
  • Date: 2015
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/174812 , vital:42512 , https://doi.org/10.1080/02572117.2015.1056455
  • Description: This article aims to develop the concept of ‘meaningful engagement’ in terms of the contemporary language policy implementation framework in South Africa. By exploring the current language policies, implementation and the current lack of effectiveness, the authors offer a new implementation focus drawn from the legal concept of ‘meaningful engagement’. ‘Meaningful engagement’ is a concept within the socio-economic rights sphere. This article expands and advances the concept within a language policy framework. Against the enabling legislative environment created by the Use of Official Languages Act 12 of 2012 and the overarching Constitutional framework which embeds the rights of all official languages, ‘meaningful engagement’ is developed and applied to selected language policies and practices.
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  • Date Issued: 2015

"Let loose in the unthinkable unspeakable": waiting and alterity in Samuel Beckett's trilogy

  • Authors: Marais, Jessica
  • Date: 2016
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/3917 , vital:20557
  • Description: In this thesis, I examine the interrelated roles of waiting and alterity in Samuel Beckett's trilogy of novels: Molloy, Malone Dies and The Unnamable. The conventional understanding of waiting is as an intentional relationship between a waiting subject and an awaited object. This kind of waiting is end-directed, and, in order for it to be worthwhile, the awaited must, at some point, arrive. In the trilogy, however, the awaited never does arrive, and it is my contention that the novels are concerned with an unconventional kind of waiting, which, being without object or end, takes the form of a non-intentional relationship between waiter and awaited. Significantly, through the non-intentional wait, the subject awaits the unawaited. She or he thereby encounters the radically other, or that which cannot be rendered familiar or assimilated in any way – an unthinkable, unspeakable, ungraspable excess that overflows the limits of thought and language. The texts foreground the vexed question of response to such alterity: how can one approach the ungraspable as ungraspable, when it is in the nature of any approach to attempt to grasp? I argue that the texts explore a paradoxical form of "incurious seeking" as an avenue to accommodate the absolutely other.
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  • Date Issued: 2016

2010 FIFA World Cup stadium investment: Does the post-event usage justify the expenditure?

  • Authors: Humphrey, Luke , Fraser, Gavin C G
  • Date: 2016
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/470954 , vital:77403 , https://www.ajol.info/index.php/aref/article/view/162154
  • Description: This paper provides an ex-post analysis of the utilisation of the stadiums that were built for the 2010 FIFA World Cup. The South African government invested approximately US $1.57 billion and US $523 million into the development of new stadiums and upgrades to existing stadiums, respectively. This paper determines whether the substantial investments into the stadiums’ infrastructure are justified by the utilisation of the stadiums after the 2010 FIFA World Cup event. A utilisation rate and a stadium usage index were used to analyse the utilisation benefits derived from the stadiums. Generally, the results suggest that there has been a significant decline in the utilisation of stadiums following the 2010 FIFA World Cup. Furthermore, the results indicate that the exorbitant costs of the stadiums for the 2010 FIFA World Cup were significant in relation to the underutilisation of the stadiums in the wake of the event. The 2010 FIFA World Cup has left the country with an expenditure legacy of an oversupply of stadiums, thus making some of the stadiums unsustainable. The results of this study appear to be in line with existing empirical research, which suggests that stadiums tend be underutilised and pose a financial burden for a host nation, subsequent to a mega-event.
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  • Date Issued: 2016

2OS

  • Authors: Machanick, Philip
  • Date: 2016
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/439214 , vital:73556 , https://homes.cs.ru.ac.za/philip/Courses/CS2-OS/Cs2ToOS.pdf
  • Description: In this book I approach the problem of understanding an OS from the point of view of a C programmer who needs to understand enough of how an OS works to program efficiently and avoid traps and pitfalls arising from not understanding what is happening underneath you. If you have a deep understanding of the memory system, you will not program in a style that loses significant performance by breaking the assumptions of the OS designer. If you have an understanding of how IO works, you can make good use of OS services. As you work through this book you will see other examples.
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  • Date Issued: 2016

A bitcoin framework : an alternative payment system for marginalized areas of South Africa using low-end mobile phones

  • Authors: Dlamini, Nelisiwe Peaceness
  • Date: 2016
  • Subjects: Electronic funds transfers -- South Africa Bitcoin -- South Africa Mobile commerce -- South Africa
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10353/11884 , vital:39115
  • Description: The emergence of the cryptocurrency Bitcoin, has invoked the need for developing financial systems that can be used to transfer digital value. This would serve as a solution to developing countries especially the challenged ones, when it comes to accommodating the financial needs of the disadvantaged people. Moreover, it facilitates access to financial services to allow them to transact with ease. Numerous companies have taken advantage of the prevalence of mobile phones and introduced financial platforms to provide financial inclusion to disadvantaged people. Financial institutions and Mobile Network Operators (MNO) have developed platforms such as cell phone banking services, mobile money, mobile wallets, and electronic wallets that can be used to provide affordable financial services. Although this is the case, alternative platforms that are affordable and accessible through mobile phones are still required. Therefore, this study proposes a Bitcoin framework that can be used as an alternative platform through low-end mobile phones to provide access to financial services to the disadvantaged people in marginalized areas. To prove the concept of the proposed Bitcoin framework, a Mobile Bitcoin Wallet System (MBWS) prototype was developed, which allows a person using a low-end mobile phone with no intervening technology such as Internet or Bluetooth, to access a Bitcoin wallet by sending a Short Message Service (SMS). This enables Bitcoin to be accessed more easily and affordably by the people. Thus the developed prototype conceptualizes an alternative payment system or a payment method that can augment the existing payment methods. The MBWS is evaluated to assess if it can offer the services that other platforms offer by being compared to a cell-phone banking service. It was deployed on a computer connected to the Internet to enable a connection to the Bitcoin network and access to the blockchain which records all the transactions that take place in Bitcoin. Although this system provides access to the Bitcoin wallet, for it to be applied to areas where people require an alternative payment system, it still needs to be enhanced for such use. This includes scaling the system and adding more functions to it.
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  • Date Issued: 2016

A business intelligence framework for supporting strategic sustainability information management in higher education

  • Authors: Haupt, Ross
  • Date: 2016
  • Subjects: Business intelligence , Strategic planning -- Management
  • Language: English
  • Type: Thesis , Masters , MCom
  • Identifier: http://hdl.handle.net/10948/5319 , vital:20832
  • Description: In the higher education sector, a number of Higher Education Institutions (HEIs) are playing a leading role in promoting sustainable initiatives. Effectively managing these initiatives however can be a complex task and requires data and information from multiple aspects of operations. In an HEI, operating sustainably means ensuring financial sustainability, social sustainability, environmental sustainability and educational sustainability. In order to manage sustainability effectively, HEIs require an integrated tool that can provide information on all areas of sustainability. HEIs face a number of challenges in effectively managing sustainability information, such as siloed data and information, and poor sharing and communication of information. Business Intelligence (BI) can assist in overcoming many of the challenges faced by organisations in effectively managing strategic sustainability information. This study investigates both the constraints to effective sustainability information management and the challenges of BI. A BI framework to support effective strategic sustainability information management is proposed. Nelson Mandela Metropolitan University (NMMU) is one such HEI, which is affected by the challenges of managing strategic sustainability information. NMMU is therefore used as a case study in this research. A BI solution, Sustainable BI, was developed based on the proposed framework. The main goal of sustainable BI is to provide strategic management at NMMU with a tool that can provide integrated sustainability information that can assist in overcoming the challenges in effectively managing strategic sustainability information. Sustainable BI was evaluated by strategic management at NMMU who are responsible for managing sustainability at NMMU. The evaluation took place through a usability study. The study revealed to what extent Sustainable BI could effectively manage strategic sustainability information at NMMU. The BI framework was iteratively improved on based on the results of the evaluations. The contributions from this study are a model for sustainability management, a BI Framework to support strategic sustainability information management and a BI solution, Sustainable BI.
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  • Date Issued: 2016

A case for contemporary third literature: the black experience in the postmillennial fiction of three Kwela authors

  • Authors: Mthembu, Lumumba
  • Date: 2016
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/3322 , vital:20480
  • Description: This study seeks to uncover the manner in which the young black experience is constructed in three novels by Sifiso Mzobe, Kgebetli Moele and K. Sello Duiker. Young Blood, Untitled and Thirteen Cents all feature teenage narrators navigating the social milieu of South Africa in the twenty-first century. My analysis is informed by Frantz Fanon’s postcolonial theory because South Africa’s socio-economic landscape conforms to the divisions laid out in The Wretched of the Earth. I contend that post-apartheid South Africa is developing in a manner that is symptomatic of the Fanonian post-independence African state. My close reading of the novels teases out the conditions under which young black subjects must survive and express themselves. I look into the roles of the community, the government, the family, and the school in shaping this experience. Naturally, my discussion segues into questions of sexuality and gender as they intersect with race. I demonstrate how these texts fail and succeed as works of Third Literature, a genre derived from Third Cinema, which I have adapted due to its Fanonian ideological underpinning. Third Literature is a fundamentally revolutionary and activistic genre which seeks to pave the way for social change. In this regard, I concern myself with the recommendations these three authors may have for the readers of their texts. In conclusion, these texts demonstrate that racialized identities are social constructs with measurable experiential effects. However, there are ways of actively resisting or even
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  • Date Issued: 2016

A case study of democratic debate on People's Choice (PC) FM "Thahameso" and Harvest FM "Tsa Mabatooa" in Lesotho

  • Authors: Falatsa, Mamolise Martha , Thipa, Henry
  • Date: 2016
  • Subjects: Radio addresses, debates, etc. -- Lesotho , Radio broadcasting -- Lesotho , Mass media -- Political aspects -- Lesotho , Civil rights -- Lesotho
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10948/7281 , vital:21314
  • Description: The study investigates the role of media in promoting free debate in Lesotho: A case study of democratic debate on People’s Choice (PC) FM “Thahameso” and Harvest FM “Tsa Mabatooa in Lesotho. Firstly, the study looked at the democratic communication in the volatile democracy of Lesotho, by providing historical factors of pre-independence and authoritarian governments, democrocatic governments prevailing and the dependence on South Africa. Secondly, the study provided literature on the role of broadcast media in different forms of government globally. Thirdly, it provides the analysis and transcription of one month’s recordings of the two political talk shows in Sesotho and identifies the communicative strategies used in this live on-air political discussion by talk show hosts, guests and callers. In these talk shows the researcher identifies the caller, host and guest behaviour and attitudes in discussions that relate the current political situation to the historical development of democracy in Lesotho alongside the economic and political influences from South Africa. The researcher also identifies that the talk show, guests and callers in the challenging political climate use traditional figurative expressions and biblical quotations to express their views. This leads the researcher to conclude that the political talk shows indeed facilitate participatory communication.
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  • Date Issued: 2016

A case study of public service delivery in Cookhouse, Eastern Cape

  • Authors: Makrwalana, Nomlindo Lillian
  • Date: 2016
  • Subjects: Local government -- South Africa -- Eastern Cape , Municipal services -- South Africa -- Eastern Cape , Municipal services -- Management -- South Africa -- Eastern Cape , Sustainable development -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10948/6986 , vital:21188
  • Description: In South Africa the economic gaps imposed by the previous apartheid government aggravated economic inequalities and caused considerable disparities, which has resulted in high unemployment rates. Inequalities were also manifest in the neglect of infrastructural and service provision as well in the effective absence of independent governance among some race groups. This led to a call for pro-active initiatives by the post-1994 democratic government to remedy the living condition of the previously disadvantage people. As part of this poverty relief drive the South African government has embarked on a series of developmental initiatives in bringing infrastructure related service to the poor and to reduce the enormous prevailing backlog, with the aim of increasing community participation, improving service delivery and promoting the upliftment of the lives of poor people through the medium of local governance. This study investigated the integrated Development Planning, which has been undertaken in Cookhouse in Blue Crane Route Municipality in the Eastern Cape to respond to the prevailing poverty and underdevelopment among the poor communities.
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  • Date Issued: 2016

A case study of the opportunities and trade-offs associated with deproclamation of a protected area following a land claim in South Africa

  • Authors: Krüger, Ruth , Cundill, Georgina , Thondhlana, Gladman
  • Date: 2016
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/67791 , vital:29145 , https://doi.org/10.1080/13549839.2015.1065804
  • Description: Publisher version , Reconciling conservation and social justice imperatives is a major challenge facing many postcolonial states worldwide. Where historically disenfranchised communities have laid legal claim to protected areas, the typical resolution has been collaborative management agreements between the state and claimant communities. The real outcomes of such strategies for people and ecosystems have been seriously questioned, although alternative approaches are seldom explored. Here, we reflect on one such alternative that was pursued in a case in South Africa, where the land was handed back to the community and a replacement protected area created. Our objective was to explore the opportunities and trade-offs associated with this approach for communities and conservation agencies alike, and to compare these to typical collaborative management outcomes. Methods included key informant interviews, focus group discussions and household surveys. We find that, surprisingly, this approach created more benefits for the conservation agency than for claimant communities. Indeed, the community experiences bore a striking resemblance to those experienced in collaborative management settings: intra-community conflict, confusion over leadership and serious questions about the boundaries of the “community”. Processes aimed at redressing past injustice in disputes over conservation land, regardless of the approach adopted, must bring with them a strong commitment to building institutional and leadership capacities within communities, and pay serious attention to the ways in which equity and social justice can be fostered after the settlement of a land claim. Settlement agreements are frequently treated as the final step towards social justice, but are in fact just the beginning.
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  • Date Issued: 2016

A case study on the health risks related to flood disasters in South Africa

  • Authors: Tandlich, Roman , Ncube, Mbonisi , Khamanga, Sandile M , Zuma, Bongumusa M
  • Date: 2016
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/75917 , vital:30482 , DOI: 10.20965/jdr.2016.p0732
  • Description: Floods occurred in the Ndlambe Local Municipality in South Africa in October 2012. During various stages of the post-disaster recovery, bacterial concentrations were measured in water and soil samples from the flood zone. All drinking water concentrations of E. coli were below 1–3 colony forming units per 100 millilitres (CFUs/100 mL). The flood waters contained between 46500 to more than 100000 CFUs/100 mL of E. coli. {The concentrations of Salmonella spp. in the flood waters varied from 5000 to 250000 CFUs/100 mL. The presumptive Vibrio spp. concentrations in flood waters ranged from 1000 to over 150000 CFUs/100 mL. {The soil concentrations for E. coli ranged from 1 to above 330 colony-forming units per 1 g of soil dry weight (CFUs/g). The soil concentrations of Salmonella spp. varied from below 1 to 22 CFUs/g. The estimated airborne fungal concentrations ranged from 16820 to 28540 colony-forming units per 1 cubic meter. An outbreak of an infectious disease was recorded among the volunteers who assisted with the post-disaster recovery. The likely bacterial causative agents included strains of Aeromonas spp. and Vibrio cholerae. Any human contact with either the contaminated flood waters or of flooded dwellings should only occur, if the individuals in questions are equipped with the full-body personal protective gear. Non-governmental stakeholders performed majority of the post-disaster recovery operations, as the local government could only cover 11% of the required costs. Applying sanitation funds to disaster recovery and increased use of the low-cost flood defence products in high risk areas could provide a solution for the future.
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  • Date Issued: 2016

A change management model for the implementation of environmental sustainability principles at General Motors South Africa

  • Authors: Mzuzu, Ncedisa
  • Date: 2016
  • Subjects: General Motors Corporation Organizational change -- Management , Corporate culture Business ethics
  • Language: English
  • Type: Thesis , Masters , MBA
  • Identifier: http://hdl.handle.net/10948/48047 , vital:40466
  • Description: In this day and age, Environmental issues are considered to be very pertinent in a business environment. Lee (2010) argues that the natural environment is not only important for the general population, but the concern for the natural environment has become increasingly important within the accounting practice. Lee (2010) references (Porter & Van der Linde, 1995; Schaltegger & Wagner, 2006; Lee, 2009), in supporting his argument that there has been increasing interest in the relationship between environmental and economic performance, that is to say reducing costs while simultaneously improving environmental performance. Organisation in the past decades have either opted to disregard or embrace change as a result of this global phenomenon. Within organisations current leaders have had to manage operations in their local areas with a global mindset. Hill (2011:4) defines globalisation as a process whereby barriers to cross border trade and investment are declining, perceived trading distances are shrinking, material culture is starting to look similar and where national economies are merging to an interdependent, integrated economic system. With the increased hype and awareness of environmental and sustainability issues within the manufacturing environment, certain companies have adopted best practices that focus on firms' production processes (Hart, 1995; Stead & Stead, 1995) that can result in cost advantage. Within the South African context, the government has put in place a legislative framework laid down by the South African Constitution that enforces the responsibility of sustainable use of natural resources and responsible management of process outputs such as waste, effluent and gas emissions. General Motors adopted an Environmental Management System. The fundamental principles of EMS are based on continuous improvement where most of improvement opportunities and challenges exist within the implementation stages. The fundamental questions the study seeks to address are: As General Motors South Africa put in place this sustainability tool, how does the company ensure that in line with continuous improvement, the improvements are sustained? What interventions can the company implement to drive the change to ensure that it improves the implementation of its Environmental Management System so as to reap the benefits as outlined? This research effort discussed recommendations for achieving the objective of developing a change management model for improving implementation of sustainability principles at General Motors South Africa. Based on the outcome of the survey and the interview, the current senior managers at General Motors South Africa have embraced environmental issues, but there is no clear indication that the future leaders will also do the same. Based on the eight steps for transforming an organisation by Kotter (2006), the following are recommendations: A communication strategy to all employees (including leadership) that will continuously articulate connections between new behaviours and corporate success throughout the organisation, and not limit to manufacturing operations. Secondly, the company needs to ensure that there are programmes in place for leadership development and succession.
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  • Date Issued: 2016

A chiral hemiporphyrazine derivative

  • Authors: Wu, Yanping , Gai, Lizhi , Xiao, Xuqiong , Lu, Hua , Li, Zhifang , Mack, John , Harris, Jessica , Nyokong, Tebello , Shen, Zhen
  • Date: 2016
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/240404 , vital:50831 , xlink:href="https://doi.org/10.1002/asia.201600754"
  • Description: The synthesis of an optically active hemiporphyrazine with chiral binaphthyl substituents (1) is reported, providing the first example of the incorporation of an intrinsically chiral moiety into the macrocyclic core of a hemiporphyrazine analogue. A negative circular dichroism (CD) signal is observed in the 325–450 nm region of the CD spectrum of (S,S)-1, while mainly positive bands are observed in the 220–325 nm region. Mirror symmetry is observed across the entire wavelength range of the CD spectra of (R,R)-1 and (S,S)-1. An irreversible one-electron oxidation wave with an onset potential at 1.07 V is observed by cyclic voltammetry, along with a reversible one-electron reduction wave at −0.85 V. Density functional calculations reproduce the experimentally observed data and trends, and provide further insight into the nature of the electronic transitions.
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  • Date Issued: 2016

A combinatorial analysis of barred preferential arrangements

  • Authors: Nkonkobe, Sithembele
  • Date: 2016
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/36228 , vital:24530
  • Description: For a non-negative integer n an ordered partition of a set Xn with n distinct elements is called a preferential arrangement (PA). A barred preferential arrangement (BPA) is a preferential arrangement with bars in between the blocks of the partition. An integer sequence an associated with the counting PA's of Xn has been intensely studied over a century and a half in many different contexts. In this thesis we develop a unified combinatorial framework to study the enumeration of BPAs and a special subclass of BPAs. The results of the study lead to a positive settlement of an open problem and a conjecture by Nelsen. We derive few important identities pertaining to the number of BPAs and restricted BPAs of an n element set using generating- functionology. Later we show that the number of restricted BPAs of Xn are intricately related to well-known numbers such as Eulerian numbers, Bell numbers, Poly-Bernoulli numbers and the number of equivalence classes of fuzzy subsets of Xn under some equivalent relation.
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  • Date Issued: 2016

A comparative physicochemical study of unsymmetrical indium phthalocyanines in the presence of magnetic nanoparticles or quantum dots

  • Authors: Osifeko, Olawale L , Nyokong, Tebello
  • Date: 2016
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/188743 , vital:44781 , xlink:href="https://doi.org/10.1080/00958972.2016.1152628"
  • Description: Asymmetric indium phthalocyanine (3, containing an NH2 group) was conjugated (via an amide bond) to magnetic nanoparticle (MNP) functionalized with carboxylic acid or glutathione-capped CdTe/ZnSe/ZnO quantum dots to form 3-MNPs or 3-QDs. Techniques such as time-resolved fluorescence measurements, transmission electron microscopy, XPS, elemental analysis, FTIR, NMR (1H, 13C, and cozy), electronic spectroscopy, as well as mass spectroscopy were employed to characterize 3 and its nanoconjugates. The phthalocyanine conjugated to quantum dot (3-QDs) possesses the lowest Фpd higher Ф∆ and ФT as well as longer triplet lifetimes compares to 3-MNPs and free phthalocyanine.
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  • Date Issued: 2016

A comparative study of syllables and morphemes as literacy processing units in word recognition: IsiXhosa and SeTswana

  • Authors: Probert, Tracy Nicole
  • Date: 2016
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/3266 , vital:20415
  • Description: Word recognition is a core foundation of reading (Invenizzi and Hayes 2010) and involves interactions of language skills, metalinguistic skills and orthography. The extent of the interaction with one another in reading has yet to be fully explored, especially in the Southern-Bantu languages. This comparative study of isiXhosa and Setswana explores this three-way interaction between language skills (effect of Language of Learning and Teaching (LoLT)), metalinguistic skills (Phonological and Morphological Awareness) and orthography (conjunctivism vs. disjunctivism). This thesis is novel in three respects, (a) a set of linguistic-informed reading measures were developed in isiXhosa and Setswana for the first-time, (b) to my knowledge, the comparisons made and study of Morphological Awareness in the Southern-Bantu languages have never been done, and (c) the use of d-prime as a way of testing for grain size in reading is an innovative approach. Grade 3 and Grade 4 learners were tested on four independent linguistic tasks: an open-ended decomposition task, a Phonological Awareness task, a Morphological Awareness task and an independent reading measure. These tasks were administered to determine the grain size unit (Ziegler and Goswami 2005, Ziegler et al. 2001) which learners use in word recognition, with the grain sizes of syllables and morphemes being studied. Results showed that syllables were the dominant grain size in both isiXhosa and Setswana, with morphemes as secondary grains in isiXhosa. Grain size differed slightly between the two orthographies. These results are reflected in the scores on the metalinguistic tasks. LoLT was not shown to have a significant impact on word recognition in first-language reading. The Psycholinguistic Grain Size Theory (PGST) was found to be the most applicable model of word recognition to the Southern- Bantu languages, as opposed to the Dual-Route Cascade Model and Orthographic Depth Hypothesis. This thesis concludes with suggested adaptations to this theory in order to allow for morpheme grain size to be included. This study has implications for teaching practice and curriculum design, and contributes to a broader understanding of literacy in the foundation phase in the Southern-Bantu languages.
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  • Date Issued: 2016

A comparison of muscle fatigue responses between static and quasi-static exertions

  • Authors: Nel, Conrad
  • Date: 2016
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/3475 , vital:20502
  • Description: Background: This study examined localized muscle fatigue responses from sub-maximal quasi-static work protocols and additionally how it compares to purely static work. The goal was to produce research that enhances the understanding of the demands on muscles during manual work to aid in preventing injuries stemming from localized muscle fatigue. Injury rates remain a problem in manual labour sectors, particularly for the lower back and shoulder regions for the manufacturing, service and construction sectors, and for knee and elbow flexors in the sports sector. Few studies have looked at quasi-static work and what the resulting fatigue characteristics are, especially when compared to purely static or purely dynamic work. This comparison is particularly important due to the fact that risk assessment tools that are currently utilized to assess risk in the working environment are based on fatigue studies that focus on purely static or purely dynamic work. This requires attention as many working situations are neither static nor dynamic, but rather quasi-static in nature, with aspects of both dynamic and static muscle components. The scope of this study only encompasses the comparison between purely static and quasi-static work. Objectives: This study had two objectives, firstly, to determine what the fatigue characteristics of quasi-static work are and how it compares to fully static work. Secondly, to determine whether an underlying static component within an otherwise dynamic muscle force affects localized muscle fatigue compared to quasi-static work that has equal amounts of effort but with no underlying static component. Methods: Four experimental conditions were tested, each on four muscles, namely the medial deltoid, bicep brachii, bicep femoris and erector spinae muscles. To test the two objectives of this study, 16 volunteers performed a five minute fatigue protocol, that either entailed a fully static condition which involved: 1) producing a steady force at 25 percent of maximum voluntary force, 2) a quasi-static condition with fully dynamic muscle force that alternates the required force level between zero and 50 percent of maximum force, 3) a quasi-static condition with an underlying static component of five percent of maximum force, or 4) a quasi-static condition with a large underlying static component of 15 percent of maximum force. All the experimental conditions in this study had the same average workload of 25 percent of maximum voluntary force over time and thus total workload. The dependant variables of interest were ratings of perceived exertion, changes in muscle fibre recruitment (% of maximum EMG activity), maximum force and center frequency from a spectral analysis of the surface electromyography. These were measured throughout the protocols at one minute intervals to determine how muscle fatigue progressed, and how the fatigue responses differed between conditions. Results: The data from comparing fully static and quasi-static work showed that of the variables measured, the rating of perceived exertion (RPE) and maximum force data indicated that for bicep brachii and bicep femoris muscles, fully static work is more fatiguing than work that alternates between zero and 50 percent of maximum force. The results for the medial deltoid and erector spinae muscles were inconclusive. The findings regarding the comparison between quasi-static conditions with and without an underlying static component revealed that an underlying static component results in greater fatigue when compared to a quasi-static condition with no static component. The results may also suggest that a larger static component coupled with a smaller peak force results in less fatigue than a condition with a small underlying static component coupled with a higher peak force in some scenarios, provided total work is kept constant. All conditions had to have the same workload in order to be validly compared and thus the condition with a larger underlying static component had a lower peak force compared to the condition with no underlying static component or the condition with a small underlying static component. Conclusions: This study presented evidence that quasi-static work does not induce fatigue when measured by RPE and drop in maximum force in the same way as static work. Additionally, the results indicate that a larger underlying static component does not necessarily fatigue a muscle faster if the overall workload is kept constant. However, the results do suggest that any underlying static component will increase the demand on a muscle when compared to a muscle exertion with no static component. When considering the available literature on how muscles fatigue during low level static contractions, the current understanding is that the larger the force during a static contraction, the faster the onset of fatigue and decrements in performance occur. The results of this study suggest that this same relationship cannot be applied to quasi-static work where an underlying static component is part of an otherwise dynamic muscle force. Thus total workload or peak force may play a larger role than the static muscle exertion in some scenarios.
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  • Date Issued: 2016
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