The effects of buffer molarity, agitation rate and mesh size on verapamil release from modified release mini-tablets using USP Apparatus 3
- Authors: Khamanga, Sandile M , Walker, Roderick B
- Date: 2007
- Language: English
- Type: text , Article
- Identifier: vital:6386 , http://hdl.handle.net/10962/d1006307
- Description: The effects of agitation rate, buffer molarity,and mesh size on the dissolution rate of verapamil hydrochloride from sustained release matrix tablets were studied using USP Apparatus 3. Eudragit® and Carbopol® were used as rate-retarding polymers in tablets prepared by wet granulation.The study was conducted to determine whether the drugs exhibit similar release characteristics when tested under the same dissolution conditions. It was found that the dissolution rate of verapamil hydrochloride was affected by the variables assessed in these studies.
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- Date Issued: 2007
The effects of fire on post-fire seed germination of selected Savanna woody species
- Authors: Shackleton, Charlie M
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/183104 , vital:43912 , xlink:href=" https://doi.org/10.1111/j.1365-2028.2007.00766.x"
- Description: Although fire is recognized as an integral component of savanna dynamics, there is a dearth of understanding of its impacts on woody plant seeds. This study examined the impacts of fire in stimulating or constraining post-fire germination of seven common savanna woody species. Seeds of two species (Combretum hereroense and Euclea natalensis) failed to germinate irrespective of fire treatment. For the remaining five species, fire effects were dependent on seed location as either on the soil surface or buried. For surface seeds, fire effects reduced germination in four of the species, and stimulated it for one species (Acacia swazica). For buried seeds, fire had no effect. A significant proportion of surface seeds were destroyed by fire, and overall germination was higher for buried seed for most species other than A. swazica.
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- Date Issued: 2007
The Emerging Role of ubuntu-botho in Developing a Consensual South African Legal Culture
- Authors: Kruuse, Helen , Midgley, Rob
- Date: 2007
- Language: English
- Type: Article , text
- Identifier: http://hdl.handle.net/10962/54224 , vital:26413 , https://dspace.library.uu.nl/handle/1874/27652
- Description: Legal culture in apartheid South Africa has variously been described as conservative and positivist, with judicial deference to the executive and to parliamentary sovereignty; formalistic, technical and authoritarian; and ‘of reasoned argument’ and justification. Until 1994, law drew its legitimacy from the very fact that it was state sanctioned, and the material context or the social aftermath of the application of a rule was in many instances deemed irrelevant. However, the adoption, first, of the interim Constitution, and later the final Constitution, saw a desire to transform this legal culture. The Constitution is now more than a formal document regulating public power: it also embodies a normative value system in terms of which judges are called upon to interpret laws and their application.
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- Date Issued: 2007
The humanities, vocationalism and the public good: exploring 'the Hamlet factor'
- Authors: Wright, Laurence
- Date: 2007
- Language: English
- Type: text , article
- Identifier: vital:7028 , http://hdl.handle.net/10962/d1007214 , https://doi.org/10.1080/17535360712331393503
- Description: preprint , This paper argues that the social mission of the humanities is no longer well understood by the public, sometimes not even by the very institutions seeking to attract students to these disciplines, the universities. It becomes difficult to argue for the cogency of research in the humanities, let alone for a specific national research agenda, when the general relation between the humanities and society is widely mistaken. To address such misapprehensions, the discussion outlines as clearly as possible the characteristic procedures of the humanities, the manner in which they inform individual and social transformation, and the contemporary predicament which makes them more rather than less needed in society’s repertoire of educational resources. With this understanding in place, the paper then puts forward suggestions for strengthening research in the humanities as part of a broader programme to renovate the humanities in the South African education system.
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- Date Issued: 2007
The relevance of sustainable development principles and goals through a case study of Gold Fields and Living Gold
- Authors: Ferreira, Adrian
- Date: 2007
- Subjects: Uncatalogued
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/192977 , vital:45286
- Description: The conventional definition of sustainable development as proposed by the Brundtland Report (United Nations, 1987), involving the integration of economic, social and environmental components, is widely accepted. Presumed benefits of these current framework applications tend to perpetuate a business as usual status, with no real sustainable development occurring. The growing debate surrounding this topic makes the case for relevant and contextual inputs to be included into sustainable development objectives. A case study, of Gold Fields and Living Gold, attempts to create a deeper understanding of the components of this debate, and begins to contextualise sustainable development principles, goals and their outcomes. This is carried out though an enquiry of the use of cultural development as a fourth sustainable development category. The case study includes the opinions of a directly affected local community entity (Living Gold) in order to observe the difference between the two organisations (Gold Fields and Living Gold). During the study, the focus began to move away from purely unabated growth impacts and looked to the creation and fostering of resilience and flexibility by the use of adaptive management. In breeding states of resilience, it was recognised that cultural impacts played an important role in ensuring long term systemic resilience. The case study involved assessing the feedback and responses of strategically selected individuals at both organisations, with Gold Fields representing a more western centric entity and Living Gold a formal representation of a traditional/ indigenous community. Similarities and differences were assessed in order to understand how current sustainable development criteria might differ between organisations that have different end objectives in mind, yet are dependent on each other. The findings resulted in a perspective of how culture could be used to describe the qualities of a local community, and how to begin aligning development goals with affected communities. The result was the development of the Integrated Resilience Sustainability Method and the consequent development of the Balanced Bottom Line Framework, which seeks to promote sustainable development along the lines of economic, social, environmental and cultural development. , Thesis (MBA) -- Faculty of Commerce, Rhodes Investec Business School, 2007
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- Date Issued: 2007
The synthesis, fluorescence behaviour and singlet oxygen studies of new water-soluble cationic gallium (III) phthalocyanines
- Authors: Durmus, Mahmut , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/280207 , vital:55586 , xlink:href="https://doi.org/10.1016/j.inoche.2006.11.012"
- Description: The preparation of cationic water-soluble gallium phthalocyanine derivatives are described for the first time. Peripheral and non-peripheral 3-hydroxypyridine tetrasubstituted gallium(III)phthalocyanines (5a, 6a) and their quaternarized derivatives (5b and 6b) have been synthesized and characterized by elemental analysis, IR, 1H NMR spectroscopy, electronic spectroscopy and mass spectra. The quaternarized compounds (5b and 6b) are soluble in water and not aggregated (in water and in organic solvents) within a wide concentration range. General trends are described for singlet oxygen quantum yields, fluorescence quantum yields and fluorescence lifetimes of these compounds. These complexes showed better singlet oxygen quantum yields in water than the related quarternarized porphyrazine complexes.
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- Date Issued: 2007
The thirtieth anniversary of the Soweto uprisings: reading the shadow in Sam Nzima's iconic photograph of Hector Pieterson
- Authors: Simbao, Ruth K
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147536 , vital:38647 , https://doi.org/10.1162/afar.2007.40.2.52
- Description: This haunting photograph (Fig. 1) from the 1976 Soweto Uprisings in South Africa is often referred to as the single most important photograph to emerge from the struggle against apartheid (Purtilo 1999:22). According to South African film director Feizel Mamdoo, there are particular moments in history that are defined by photographic, celluloid, or television images, such as the world famous photograph of the Saigon girl, naked and burning from napalm (Worsdale 1998; see also Richards 2001). He argues that the iconic photograph by Sam Nzima depicting Hector Pieterson being carried in the arms of Mbuyisa Makhubu, with his distraught sister Antionette1 running alongside, is comparable in the way that “it marks history, both social and personal” (Worsdale 1998).
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- Date Issued: 2007
Think Piece : an opening dialogue with Think Pieces and feature articles on learning in a changing world in this journal
- Authors: Lotz-Sisitka, Heila
- Date: 2007
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/59602 , vital:27630 , https://www.ajol.info/index.php/sajee/article/view/122734
- Description: From Conclusion:This opening Think Piece invites you into such a dialogue, with this journal, its words and flows of meaning, and with the World Environmental Education Congress, its words and flows of meaning. Dialogue, as explained by Bohm, and as illustrated in the thought experiments in this paper, is a process of creatively and experimentally seeking out meaning and coherence through listening, and through deeper explorations of the tacit, implicate order. It is also a free process, where you as individual are invited to seek out the relations between your thoughts and the collective. Welcome to the process.
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- Date Issued: 2007
Thiol oxidation at 2-mercaptopyrimidine-appended cobalt phthalocyanine modified glassy carbon electrodes
- Authors: Obirai, Joseph C , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/281403 , vital:55722 , xlink:href="https://doi.org/10.1016/j.jelechem.2006.10.033"
- Description: The electrocatalytic activity of cobalt tetra-2-mercaptopyrimidylphthalocyanine-modified glassy carbon electrode (CoTMPyrPc-GCE) toward gluthathione, L-cysteine and 2-mercaptoethanol has been investigated. CoTMPyrPc-GCE provides a significant improvement on the reported oxidation potential of L-cysteine in pH 4.0 phosphate buffered solution. The oxidation peak potential (Ep), for L-cysteine, was 0.15 V – a relatively lowered oxidation potential compared to reported phthalocyanine complexes. The electrode prepared by drop-dry/thermal annealing method was very stable and sensitive over a long period of time. The stability has been attributed to the thermal annealing and the structure of the mercaptopyrimidine on the periphery of the CoPc.
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- Date Issued: 2007
Time-resolved luminescence of low sensitivity quartz from crystalline rocks
- Authors: Chithambo, Makaiko L , Preusser, F , Ramseyer, K , Ogundare, F O
- Date: 2007
- Language: English
- Type: text , article
- Identifier: vital:6801 , http://hdl.handle.net/10962/d1004164 , https://doi.org/10.1016/j.radmeas.2006.07.005
- Description: preprint , Time-resolved luminescence spectra of low sensitivity natural quartz from crystalline rocks are presented. The luminescence was pulse-stimulated at width using 470 nm blue light from quartz separated from plutonic, metamorphic, volcanic and hydrothermal samples. Measurements were made at 20 °C. All samples show evidence of a short lifetime component less than long although in several cases too weak in intensity to be evaluated accurately. On the other hand, the value of the principal lifetime component varies considerably being about in metamorphic quartz, in plutonic quartz, and in one example of hydrothermal quartz. The results illustrate a new feature of luminescence from quartz for which lifetimes less than or greater than have never been reported at room temperature before. It is argued that the thermal provenance of the quartz and so the annealing it will have experienced influences the size of the observed lifetime. In particular, the results are explained in terms of a model consisting of three luminescence centers with the dominant lifetime linked to preferential recombination at one center depending on the thermal history of the sample and hence the hole concentration of the center.
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- Date Issued: 2007
Towards continental transformation: understanding sustainable peace agreements in Africa
- Authors: Bischoff, Paul, 1954-
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/161409 , vital:40624 , https://0-hdl.handle.net.wam.seals.ac.za/10520/EJC15983
- Description: There are social and political questions to be asked about the new continent-wide institutions in and around what is still a young African Union (AU). These include questions such as whether the AU and its institutions can be built in ways that will allow this body to transform Africa's international relations, and how this is to be done. What are the norms and values that will inform this change and the African renewal promoted by the AU? Is the multilateral architecture of the AU able to encourage democracy and people-centredness, for instance? Will it, in the end, be able to deliver on the hoped-for "pan-African transnational democratic revolution"?.
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- Date Issued: 2007
Transforming the media: a cultural approach
- Authors: Steenveld, Lynette N
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147891 , vital:38682 , DOI: 10.1080/02560240485310061
- Description: The change from an Apartheid state to a liberal democratic one has wrought many changes at all levels of South African society: the economic, social, political, cultural. This paper explores the impacts of these changes on the South African print media industry, with a view to assessing their contribution to the development of a democratic citizenship. While acknowledging the constraining effects of economic structures of ownership, the paper locates these within the broader social and political context of post-apartheid South Africa. It thus attempts to synthesise elements of both a political economy and cultural approach to the analysis of cultural production.
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- Date Issued: 2007
Translation processes in the design of an education for sustainable development innovations course for universities in Africa
- Authors: Lotz-Sisitka, Heila , Lupele, Justin , Ogbuigwe, Akpezi
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/127213 , vital:35978 , https://10.1080/02607470701259440
- Description: This paper traces the translation processes associated with the mobilization of resources and human agency in the development of a United Nations Environment Programme (UNEP) Education for Sustainable Development (ESD) Innovations Course for universities in Africa. University teachers are often neglected in teacher education initiatives. There are few formal professional development opportunities available for university teachers given the traditionally established hierarchy in the higher education sector as university teachers are normally the ones offering professional development to others. The paper explores how a participatory, deliberative translation process has served to provide professional development and professional exchange opportunities for university teachers which are non‐traditional and responsive to diversity, history, context and risk. The emergence of the modern African university is essentially a post‐independence (post‐1960s) phenomenon, with a few earlier African universities being colonially structured, controlled and inspired. Through a short historical overview, we introduce the African university landscape and some of its contemporary contextual and educational challenges. We then describe the process of deliberation that took place amongst university teachers from 23 African countries to initiate and establish the ESD Innovations Course. The paper concludes by arguing for open and participatory approaches in ESD teacher education course design, if we are to support university teachers (including teacher educators) to engage in mainstreaming environment and sustainability questions in higher education. The paper draws on the translation model provided by Latour in his actor network theory to describe and explain the deliberative translation process in the UNEP ESD Innovations Course. In doing this, it illuminates the possibilities of such a deliberative translation process for university teacher education. It also points to limitations encountered in applying this framework to this analysis, opening new vantage points for research of this nature in teacher education.
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- Date Issued: 2007
Tuning the redox properties of metalloporphyrin-and metallophthalocyanine-based molecular electrodes for the highest electrocatalytic activity in the oxidation of thiols
- Authors: Bedioui, Fethi , Griveau, Sophie , Nyokong, Tebello , Appleby, A John , Caro, Claudia A , Gulppi, Miguel , Ochoa, Gonzalo , Zagal, José H
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/283988 , vital:56009 , xlink:href="https://doi.org/10.1039/B618767F"
- Description: In this work we discuss different approaches for achieving electrodes modified with N4 macrocyclic complexes for the catalysis of the electrochemical oxidation of thiols. These approaches involve adsorption, electropolymerization and molecular anchoring using self assembled monolayers. We also discuss the parameters that determine the reactivity of these complexes. Catalytic activity is associated with the nature of the central metal, redox potentials and Hammett parameters of substituents on the ligand. Correlations between catalytic activity (log i at constant E) and the redox potential of catalysts for complexes of Cr, Mn, Fe, Co, Ni and Cu are linear with an increase of activity for more positive redox potentials. For a great variety complexes bearing the same metal center (Co) correlations between log i and Eo′ of the Co(II)/Co(I) couple have the shape of an unsymmetric volcano. This indicates that the potential of the Co(II)/Co(I) couple can be tuned using the appropiate ligand to achieve maximum catalytic activity. Maximum activity probably corresponds to a ΔG of adsorption of the thiol on the Co center equal to zero, and to a coverage of active sites by the thiol equal to 0.5.
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- Date Issued: 2007
Two issues, two groups:
- Authors: du Toit, Jeanne
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/159299 , vital:40285 , https://hdl.handle.net/10520/EJC144677
- Description: One of the conference strategies that I found particularly valuable was that of the "syndicate teams" who met regularly to speak on focused topics. Delegates signed up for the topic they were interested in and stayed with that group for the duration of the conference. The list included topics such as the status of journalism education in the academy; the role of journalism in changing the media; adapting journalism education to a digital age, etc.
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- Date Issued: 2007
Using the tutorial system to improve the quality of feedback to students in large class teaching
- Authors: Snowball, Jeanette D , Sayigh, E
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/70848 , vital:29752
- Description: In many universities, economics teachers now face the challenge of dealing with large, diverse classes, especially at undergraduate level. A common concern is the non-attendance at lectures of unmotivated (conscript) students. This paper presents the results of a student assessment of a macroeconomics 1 course, coupled with a self-assessment of their own input into the course. The results obtained, using an econometric model, suggest that what students do outside of lectures is equally, or more, important than lecture attendance itself. The paper concludes by examining the possibility of using peer assessed group learning as a feasible way to encourage deep learning in large classes.
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- Date Issued: 2007
Vice Chancellor New staff welcome address, 2007
- Authors: Badat, Saleem
- Date: 2007
- Subjects: Rhodes University
- Type: text
- Identifier: vital:7646 , http://hdl.handle.net/10962/d1015774
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- Date Issued: 2007
Vice Chancellor's message to the Toronto Old Rhodian Reunion
- Authors: Badat, Saleem
- Date: 2007
- Subjects: Rhodes University
- Language: English
- Type: text
- Identifier: vital:7648 , http://hdl.handle.net/10962/d1015776
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- Date Issued: 2007
Vice Chancellor's Oppidan Newspaper message, 2007
- Authors: Badat, Saleem
- Date: 2007
- Subjects: Rhodes University
- Language: English
- Type: text
- Identifier: vital:7649 , http://hdl.handle.net/10962/d1015777
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- Date Issued: 2007
Voltammetric characterisation of the self-assembled monolayers (SAMs) of benzyl-and dodecyl-mercapto tetra substituted metallophthalocyanines complexes
- Authors: Agboola, Bolade , Westbroek, Philippe , Ozoemena, Kenneth I , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/281414 , vital:55723 , xlink:href="https://doi.org/10.1016/j.elecom.2006.08.047"
- Description: Voltammetric characterisations of cobalt, iron, manganese, nickel and zinc phthalocyanine complexes tetra substituted with benzyl- and dodecyl-mercapto ring substituents and immobilisation on gold electrodes via the self-assembling technique are presented. The self-assembled films are stable and showed blocking characteristics towards the following Faradaic processes; gold surface oxidation, under potential deposition of copper and solution redox chemistry of [Fe(H2O)6 3+ ]/[Fe(H2O)6 2+ ]. The solution chemistry of [Fe(CN)6]−3/[Fe(CN)6]−4 redox process was used to study the orientation of the CoPcs-SAMs and this revealed a possible deviation from flat orientation of the complexes on the gold electrodes when the SAM formation times were greater than 24 h. For SAM formation time at 24 and 48 h, CoTDMPc-SAM showed more inhibition of the [Fe(CN)6]−3/[Fe(CN)6]−4 redox process than the CoTBMPc-SAM counterpart, indicating more blocking characteristics of the dodecylmercapto ring substituents compared to the benzylmercapto counterpart. To avoid SAM desorption, the potential application should be limited to −0.2 to +0.8 V vs. Ag∣AgCl (NaCl, sat’d) in acidic and neutral pH.
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- Date Issued: 2007