Photosensitizing properties of non-transition metal porphyrazines towards the generation of singlet oxygen
- Authors: Seotsanyana-Mokhosi, Itumeleng
- Date: 2001 , 2013-05-02
- Subjects: Phthalocyanines , Photosensitization, Biological , Active oxygen -- Physiological effect , Photosensitizing compounds
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4395 , http://hdl.handle.net/10962/d1006086 , Phthalocyanines , Photosensitization, Biological , Active oxygen -- Physiological effect , Photosensitizing compounds
- Description: Metallophthalocyanine complexes containing non-transition metals are very useful as sensitizers for photodynamic therapy, a cure for cancer that is based on visible light activation of tumour localized photo sensitizers. Excited sensitizers generate singlet oxygen as the main hyperactive species that destroy the tumour. Water soluble sensitizers are sought after for the convenience of delivery into the body. Thus, phthalocyanine (pc), tetrapyridinoporphyrazines (tppa) and tetramethyltetrapyridinoporphyrazines (tmtppa) with non-transition central metal atoms of Ge, Si, Sn and Zn were studied. First was the synthesis of these complexes, followed by their characterisation. The characterisation involved the use of ultraviolet and visible absorption spectroscopy, infrared spectroscopy, nuclear magnetic resonance spectroscopy, electrochemical properties and elemental analysis. Photochemical properties of the complexes were then investigated. Photolysis of these macrocycles showed two processes; -reduction of the dye and photobleaching, which leads to the disintegration of the conjugated chromophore structure of the dye. Photobleaching is the reductive quenching of the excited state of the sensitizers. The intensity of the quenching decreased progressively from tmtppa, tppa to pc metal complexes with photobleaching quantum yields, 6.6 x 10.5⁻¹, 1.8 x 10.5⁻¹ and 5.4 x 10⁻⁶ for Zntmtppa, Zntppa and Znpc, respectively. Efficiency of singlet oxygen sensitization is solvent dependent with very different values obtained for the same compound in different solvents, for example, 0.25 and 0.38 were observed as singlet oxygen quantum yields for Gepc complex in DMSO and DMF respectively. In DMSO the efficiency of ¹O₂ generation decrease considerably from pc to tppa and finally tmtppa. In water Getmtppa exhibits much higher singlet oxygen quantum yield, hence promising to be effective as a sensitizer for photodynamic therapy.
- Full Text:
- Date Issued: 2001
Plaatje's African romance: the translation of tragedy in Mhudi and other writings
- Authors: Walter, Brian Ernest
- Date: 2001
- Subjects: Plaatje, Sol. T. (Solomon Tshekisho), 1876-1932. Mhudi Race in literature Politics in literature
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2188 , http://hdl.handle.net/10962/d1002230
- Description: This study brings together Plaatje’s politicaland literary visions, arguing that the one informs the other. Plaatje’s literary work is used as a starting point for the discussion, and the first chapter explores the relationship of his political and artistic visions. Mhudi is his definitive romance text, and it is argued that Plaatje’s romance visionin this text is reflected in his political thinking, and in turn reflected by it. His romance work was part of a literary romance tradition which Plaatje both drew upon and transformed, and thus the basic features of romance are explored in Chapter Two. Plaatje’s work is situated between two influential romance models, therefore Chapter Two also discusses the romances of Shakespeare, whomPlaatje read as reflectinga non-racial humanism that was translatable into the African context, in terms of political vision and of literary text. His other models were the colonial romances of Haggard. It is argued that, while Plaatje could glean many elements fromHaggardthat suited his purposes as an African, specifically a SouthAfrican, writer, he nevertheless—despite his own pro-British leanings, qualified though they might have been by the complexities of his colonial context—would not have represented Africa and Africans in terms of the exotic other in the way Haggard clearly did. Thus Plaatje, in terms of his romance vision, may have usedmanyofthe themesand techniques of Haggardianromance, but consistently qualified these colonial works by using the more classically shaped Shakespearean romance structure at the deep level of his work. The third chapter examines Haggard’s romance, but differentiates between two Haggardian types, the completed or resolved romance, whichis more classical in its form, and evokes an image of a completed quest, as well as the necessity of the quester entering the world again. Haggard’s “completed” African romance, it is argued, is resolved only in terms of a colonial vision. Chapter Four, by contrast, examines examples of his unresolved African romance, in which African ideals implode, and show themselves to be inneed of foreign intervention. It is argued that Haggard’s image of Africa was based on the unresolved or incomplete romance. His vision of Africa was such that it could not in itself provide the materialfor completed romance. This vision saw intervention as the only option for South Africa. While Plaatje uses elements of Haggard’s “incomplete” romance models when writing Mhudi, he handles both his narrative and politicalcommentaryin this text in terms of his own politicalthought. This non-racial politicalvisionis guided by his belief that virtue and vice are not the monopoly of any colour, a non-racialism he associates with Shakespeare. However, within the context of the South Africa of his fictionand of his life, this non-racial ideal is constantly under threat. It is partly threatened by political forces, but also challenged by moral changes within individuals and societies. In Chapter Five the examination of Plaatje’s work begins withhis Boer War Diary, inwhicha romance structure is sought beneath his diurnal observations and political optimismduring a time of warfare and siege. The discussion of this text is followed by a reading of Native Life in South Africa in which it is argued that Plaatje looks, in the midst of personal and social suffering, for that which can translate a tragic situation into romance resolution. “Translation” is used in a broad sense, echoing Plaatje’s view of the importance of translation for cross-cultural understanding and harmony. The arguments of Chapter Five are extended into Chapter Six, where a reading of Mhudi places emphasis on the possibilities of change implied in romance. Plaatje’s non-racial humanism recognizes the great potential for injustice and human suffering within the context of South African racism, but constantly seeks to translate such suffering into the triumph of romance. While the narrative of Mhudi concludes on a romance peak, tensions between the tragic and romance possibilities alert the reader to the sense that, despite its romance resolution, something has been lost in the translation of the potential tragedy into romance.
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- Date Issued: 2001
Population structure of Apis mellifera scutellata (Hymenoptera: Apidae) filling the Uganda gap
- Authors: Radloff, Sarah E , Hepburn, H Randall
- Date: 2001
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/452017 , vital:75095 , https://hdl.handle.net/10520/EJC32956
- Description: Apis mellifera scutellata Lepeletier (Hymenoptera: Apidae) extends from South Africa to Ethiopia but includes local populations of varying morphology. The honeybees of Uganda previously represented an important biogeographical gap in defining the population structure of A. m. scutellata, but have now been resolved by morphometric analyses of worker honeybees analysed with multivariate techniques. Honeybees of lower altitudes (less than 2000 m) formed one distinct morphocluster typical of A. m. scutellata throughout the continent, while those at higher altitudes (less than 2000 m) formed a separate distinct cluster of large, dark bees. The latter occur as an archipelago of mountain ecotypes of A. m. scutellata..
- Full Text:
- Date Issued: 2001
Population structure of Apis mellifera scutellata (Hymenoptera: Apidae) filling the Uganda gap
- Authors: Radloff, Sarah E , Hepburn, H Randall
- Date: 2001
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/452021 , vital:75096 , https://hdl.handle.net/10520/EJC32956
- Description: Apis mellifera scutellata Lepeletier (Hymenoptera: Apidae) extends from South Africa to Ethiopia but includes local populations of varying morphology. The honeybees of Uganda previously represented an important biogeographical gap in defining the population structure of A. m. scutellata, but have now been resolved by morphometric analyses of worker honeybees analysed with multivariate techniques. Honeybees of lower altitudes (less than 2000 m) formed one distinct morphocluster typical of A. m. scutellata throughout the continent, while those at higher altitudes (less than 2000 m) formed a separate distinct cluster of large, dark bees. The latter occur as an archipelago of mountain ecotypes of A. m. scutellata..
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- Date Issued: 2001
Preliminary observations on the effects of hydrocortisone and sodium methohexital on development of Sarcophaga (Curranea) tibialis Macquart (Diptera: Sarcophagidae), and implications for estimating post mortem interval
- Authors: Musvasva, E , Williams, Kirstin A , Muller, Nikite W J , Villet, Martin H
- Date: 2001
- Language: English
- Type: text , Article
- Identifier: vital:7075 , http://hdl.handle.net/10962/d1009532
- Description: Larvae of Sarcophaga (Curranea) tibialis (S. tibialis) were reared at constant temperature on chicken liver treated with a steroid or a barbiturate at concentrations that would be lethal, half-lethal and twice-lethal doses for humans. Trends to greater mortality at higher drug concentrations were not statistically significant. Larvae exposed to either drug took significantly longer to reach pupation compared to those in the control, while larvae exposed to sodium methohexital passed through pupation significantly faster than those in the control. No systematic relationship was found between drug concentration and development time of larvae or pupae. The total developmental period from hatching to eclosion did not differ between treatments, implying that estimates of post mortem intervals- (PMI) based on the emergence of adult flies will not be affected by the involvement of these drugs in a case. On the other hand, anomalous pupation spans may indicate the presence of barbiturates. These findings are compared with patterns found in another fly fed other contaminants.
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- Date Issued: 2001
Processes and products in the kimberlitic crater facies of the south lobe, Jwaneng Mine, Botswana
- Authors: Machin, Kimberley
- Date: 2001
- Subjects: Kimberlite -- Jwaneng (Botswana)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4995 , http://hdl.handle.net/10962/d1005607 , Kimberlite -- Jwaneng (Botswana)
- Description: The Pennian (~ 245 Ma) Jwaneng kimberlite, situated in southern Botswana, comprises three steep-sided pipes that coalesce approximately 100m below the present day surface to fonn a 54ha body. These pipes have been labelled the South, Centre and North Lobes. The kimberlites intruded a thick sequence of Proterozoic shales, dolomites and sandstones and a thin veneer of consolidated to poorly consolidated mudstones and siltstones of the Karoo Supergroup. Although the shapes of these pipes are comparable to other southern African pipes, they are filled predominantly with crater facies volcaniclastic kimberlite. No tuffisitic kimberlite breccia, the characteristic rock type of the diatremes of other southern African pipes, has yet been identified. The Jwaneng kimberlite thus represents an exception to the standard model for southern African kimberlites, implying that different processes need to be invoked to explain its fonnation. The present study involves a detailed volcanological and sedimentological analysis of the volcaniclastic fill of the Jwaneng South Lobe. Two principal and distinct lithofacies have been identified: the quartz-free RVK facies and the quartz-bearing QRVK facies. Both facies include fine to coarse grained, predominantly massive and subordinate chaotically bedded deposits. The volcaniclastic rocks have been classified as resedimented volcaniclastic kimberlite (RVK) , since their deposition is ascribed to mechanisms dominated by mass flow processes. Based on certain characteristics and differences between the two principal facies, and their spatial distribution within the pipe, they are interpreted as being the products of at least two separate eruption episodes. Certain characteristics (e.g. }hape, granularity~ of the juvenile· magma clasts III the volcaniclastic kimberlite suggest complete crystallisation and devolatilisation of the magma at depth prior to explosive fragmentation. A scenario in which this might have occurred, and which led to catastrophic explosive eruption and pipe excavation is proposed. Explosive eruption and associated tuff cone formation is followed by resedimentation of the material back into the pipe by mass flow processes. Mass flow processes are dominated by debris flow, with lesser grain flow, hyperconcentrated flow and subaqueous mud flow and suspension settling of muddy kimberlitic sediments. Geochemical analyses of the latter indicate a high degree of contamination and weathering, and mixing between pristine kimberlite and silicic shale/mud compositions. Failure and collapse of parts of the underlying pipe walls yielded megablocks of poorly consolidated Permian Karoo mudstone in the peripheral zone of the pipe. This source of the megablocks is supported by their bulk chemical composition. Minor phreatic/phreatomagmatic eruptions are suggested by the presence of rare accretionary and armoured lapilli within both the QRVK and RVK facies. Subsidence of the volcaniclastic pipe fill, inferred mainly from the oversteepened dips of the bedded QRVK and RVK facies, may be related to gravity-induced compaction, late-stage phreatomagmatic eruptions or eruption ofthe adjacent Centre Lobe.
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- Date Issued: 2001
Project 1 - Student teachers' exploration of beadwork : cultural heritage as a resource for mathematical concepts
- Authors: Dabula, Nomonde Patience
- Date: 2001
- Subjects: Ethnomathematics , Beadwork -- South Africa -- Eastern Cape , Beadwork , Mathematics -- Study and teaching , Culture -- Study and teaching
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:1415 , http://hdl.handle.net/10962/d1003292
- Description: This portfolio consists of three research projects that predominantly lie within the socio-cultural strand. The first project is a qualitative ethnomathematical study that links students' knowledge of mathematics to their cultural heritage. The study was conducted with a group of final year student teachers at a College of Education in Umtata, Eastern Cape. These students visited a city museum where mathematics concepts were identified from beadwork artifacts. Mathematics concepts that were identified consisted of symmetry, tessellation and number patterns. Students' views about the nature of mathematics shifted radically after their own explorations. Initially students did not perceive mathematics as relating to socio-cultural practices. But now, they have reviewed their position and see mathematics as inextricably interwoven in everyday activities and as such, a product of all cultures. They also pride themselves of their own cultural heritage to have mathematical connections. A more positive attitude towards studying mathematics in this approach was noticed. Data was collected by means of interviews, reflective journal entries and photographs. The second project is a survey with a group of practising teachers who have already implemented Curriculum 2005, and a group which is about to implement it in 2001. The study sought teachers' understanding of connections between mathematics and socio-cultural issues. The new mathematics curriculum in South Africa calls for teachers to grapple well with these issues. About a third of the articulated specific outcomes specifically relate to socio-cultural issues. If teachers' understanding of these issues is poor, implementation of the new curriculum will remain a mere dream. The findings of the survey revealed that the majority of teachers could not identify the culture related specific outcomes in the new mathematics curriculum. Complicated language used in the OBE policy documents was found to inhibit meaning to these teachers. Although, all teachers showed a positive attitude towards the inclusion of socio-cultural issues in the mathematics classroom, the implementation of these outcomes was found to be very problematic. In this survey data was collected by means of questionnaires. The third project is a literature review on the need to popularise mathematics to students in particular, and to the broader public in general. The 21 st century places great technological demands. Mathematics underpins most thinking behind technological development. The role played by mathematics in advancing other fields is largely hidden to the majority of people. There is, therefore, a need to bring forth the vital role that mathematics plays in these fields. The number of students participating in mathematics is decreasing. Mathematics, as a field, is experiencing competition from other science fields. There is a need to bring some incentives to attract more students into this field and retain those mathematicians already involved. Also important, is the need to change the negative image that the public often holds about mathematics. Many people are mathematically illiterate and do not see mathematics as an everyday activity that relates to their needs. There is, therefore, a need to change the face of mathematics.
- Full Text:
- Date Issued: 2001
Pseudocloeon cataractae (Crass)(Ephemeroptera: Baetidae): new combination and lectotype designation
- Authors: Lugo-Ortis, C R , de Moor, Ferdy C
- Date: 2001
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/452189 , vital:75110 , https://hdl.handle.net/10520/EJC32950
- Description: Considerable clarification of taxonomic concepts and phylogenetic relationships within small minnow mayflies (Ephemeroptera: Baetidae) has resulted from recent studies involving Afro-tropical genera and species (Lugo-Ortiz and McCafferty 1996a, b, 1997a, b, 1998a-c; Barber-James and McCafferty 1997; McCafferty et al. 1997; Lugo-Ortiz et al. 1999; Lugo-Ortiz et al. 2001).
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- Date Issued: 2001
Re-examining local and market-orientated use of wild species for the conservation of biodiversity
- Authors: Shackleton, Charlie M
- Date: 2001
- Language: English
- Type: Article
- Identifier: vital:6655 , http://hdl.handle.net/10962/d1007071
- Description: The hypothesis of attaching and realising market values as one means of conserving biodiversity has gained ground over the last decade. This has been challenged recently after examination of a number of case studies, largely from tropical Amazonia, on high value logging, marketing of non-timber forest products, and bioprospecting. The conclusion was that market-orientated conservation has seldom generated the financial returns envisaged, and as such cannot be used as an incentive to prevent land transformation. This paper reviews the basis of the challenge to market-orientated conservation on a number of grounds, drawing on examples largely from southern Africa. It concludes that generalizations from tropical Amazonia regarding the failure of market-orientated conservation are probably premature, and that it should remain an option, amongst a number of options, for conservation of biodiversity. Additionally, the prerequisite criteria identified as necessary to create an enabling framework for the success of market-orientated conservation are insufficient. Case studies are presented where the prerequisites do not apply, yet current extraction for market purposes is sustainable. Other potential prerequisites are also considered. There is a need for multivariate analysis, based on a large sample size drawn from across a range of environments and resources, of which factors are important prerequisites for successful market-orientated conservation, and under which circumstances.
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- Date Issued: 2001
Recruiters Guidelines
- Authors: COSATU
- Date: 2001
- Subjects: COSATU
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/109753 , vital:33186
- Description: The purpose of this booklet is to touch in number of areas, which are important at this point for the recruitment campaign of the federation. It is not meant even by implication to provide details of how to handle the campaign what it does is to highlight issues and areas that we must think in the preparation for this campaign. More importantly is the fact that COSATU remains the biggest federation in South Africa and fastest growing international. Beside a loss of membership from + 2 million to + 1.8 million members. The decrease in membership is mostly because of retrenchments. The well known fact is that only about 40% of the workforce that is unionized. The aim of the recruitment drive is to access this 60% that is not unionized. The mistake must not be committed to think that the 40%, which is unionized, belong to COSATU. There are two other federations plus number of non-affiliated unions. Our commitment to One Country One Federation does not stop us to recruit from other unions as long as we remain under different bodies. This October campaign coincides with Red October campaign of the SACP and Health and Safety month of the federation this must be seen as strength than lack of co-ordination. One area that is link to recruitment is the servicing of membership. It is useless to recruit and fail to service membership because every campaign that we will take around recruitment we may find ourselves had to fight with disgruntled members and obviously it will be difficult to attract new members. This must say to us that members come first.
- Full Text:
- Date Issued: 2001
Recruiters Guidelines
- Authors: COSATU
- Date: 2001
- Subjects: COSATU
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/137210 , vital:37498
- Description: The purpose of this booklet is to touch in number of areas, which are important at this point for the recruitment campaign of the federation. It is not meant even by implication to provide details of how to handle the campaign what it does is to highlight issues and areas that we must think in the preparation for this campaign. More importantly is the fact that COSATU remains the biggest federation in South Africa and fastest growing international. Beside a loss of membership from + 2 million to + 1.8 million members. The decrease in membership is mostly because of retrenchments. The well known fact is that only about 40% of the workforce that is unionized. The aim of the recruitment drive is to access this 60% that is not unionized. The mistake must not be committed to think that the 40%, which is unionized, belong to COSATU. There are two other federations plus number of non-affiliated unions. Our commitment to One Country One Federation does not stop us to recruit from other unions as long as we remain under different bodies. This October campaign coincides with Red October campaign of the SACP and Health and Safety month of the federation this must be seen as strength than lack of co-ordination. One area that is link to recruitment is the servicing of membership. It is useless to recruit and fail to service membership because every campaign that we will take around recruitment we may find ourselves had to fight with disgruntled members and obviously it will be difficult to attract new members. This must say to us that members come first.
- Full Text:
- Date Issued: 2001
Regulation within the supracellular highway - plasmodesma are the key
- Authors: Botha, Christiaan E J , Cross, Robin H M
- Date: 2001
- Language: English
- Type: Article
- Identifier: vital:6500 , http://hdl.handle.net/10962/d1005918
- Description: Plasmodesmal connections are unique, highly dynamic intercellular structures that are lined by the plasmamembrane. They are believed to be a vital intercellular communication channel between living cells, linking numbers of living cells into interconnected, highly specialised cellular domains, thus enabling the plant to act as an integrated organism. Their evolution in the higher plant was inevitable. It is accepted that cell heterogeneity rather than cell divergence pressurised developing plant systems along a route that led to the development of intercellular passages and connections. With time these connections have evolved to allow some degree of regulation and traffic control. This paper explores some of the structure/function relationships in plasmodesmata. Attention is focused on the potential role of the neck region of these remarkable structures and discusses models which may explain the processes involved in regulating the movement of substances from cell to cell.
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- Date Issued: 2001
Removal of copper and nickel from solution by the non-viable biomass of the water fern Azolla filiculoides in an upscaled fixed-bed column system
- Authors: Thompson, Denis Alan
- Date: 2001
- Subjects: Copper , Nickel , Azolla , Heavy metals -- Absorption and adsorption
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3914 , http://hdl.handle.net/10962/d1003973 , Copper , Nickel , Azolla , Heavy metals -- Absorption and adsorption
- Description: The potential of non-viable Azalia filiculaides for the removal of Cu and Ni from aqueous solutions and the possibility of scaling up existing lab scale Azalia column systems was investigated. The effects of factors such as metal starting concentration, pH and two metals in solution on the removal of Ni and Cu from aqueous solution by dried and crushed Azalia biomass were studied in batch systems. Aqueous solutions of Ni with starting concentrations between 1000 and 2000J.lmolll gave the most efficient Ni removal by Azalla biomass. For Cu the optimum starting concentration for adsorption was 50J.lmol/l. The adsorption capacity of both eu and Ni increased as the starting pH of the sorption media increased. The optimum pH for Ni adsorption was found at pH 7 and for Cu, at pH 5. - Awlla biomass had a higher. maximum binding capacity (qrnax) for Cu than for Ni at pH 5. The removal of both Cu allct Ni showed little or no variation with the presence another metal in solution. Kinetic studies show that both Cu and Ni adsorbed rapidly onto the Azalia biomass. The removal of Cu and Ni from aqueous solutions using non-viable Azalia biomass was investigated in a lab scale fixed-bed column and an upscaled 4L column system. The nonviable Azalla filiculaides biomass when dried and used in a column for adsorption of Cu and Ni showed good physical stability under many different conditions. Preparation of the biomass before it could be used in the columns was very simple and did not involve any significant pretreatment steps. Prolonged exposure to UV light decreases Azalia biomass capacity for Ni and Cu adsorption. Column adsorption of Cu and Ni from aqueous solutions was successfully upscaled approximately 100 times. Relative to the lab scale column, the 4L column performed better for the uptake of Cu and Ni per gram of biomass. The larger column was also able to operate at relatively higher flow rates. The biomass showed good reusability with little change in the amount of Ni adsorbed in 10 consecutive cycles. Electron micrographs showecf little or no change in the physical structure and integrity of the Azolla biomass after exposure to mineral acids, Ni solution and high flow rates over 10 consecutive adsorption and desorption cycles. As much as 80% Ni and 70 % Cu was recovered when desorption profiles were generated using O.lMHCI as a desorption agent. The 4L column system was also tested using a highly concen~rat:~ Ni plating bath solution.(Nicrolyte 1). Only 18 % of the Ni could be removed from the expended Nicrolyte 1 pla~Jng solution after treating only 25L, indicating that Azolla biomass is more suited for removal of metals from more dilute industrial effluents.
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- Date Issued: 2001
Rendering Primitives for a Virtual Holodeck
- Authors: Morkel, Chantelle , Bangay, Shaun D
- Date: 2001
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/432795 , vital:72901 , https://www.cs.ru.ac.za/research/groups/vrsig/pastprojects/039virtualholodeck/paper02.pdf
- Description: The main objective of this research is to implement a “Star Trek”-like holodeck in a computer environment. An experiment to create graphical primitives and images solely out of spheres is being conducted. We investigate several approaches of creating primitives using spheres, and then using these primitives to create images. Initial results of this experiment are presented and we conclude that using spheres to create primitives and images is a viable approach to creating realistic-looking three-dimensional (3D) images.
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- Date Issued: 2001
Research for health and life: life giving light
- Authors: Burnett, Mary
- Date: 2001
- Subjects: Nyokong, Tebello
- Language: English
- Type: Article , text
- Identifier: vital:7179 , http://hdl.handle.net/10962/d1006185 , Nyokong, Tebello
- Description: The elimination of certain cancers with light, known as photodynamic therapy, is a relatively new technique that has mainly been used in Russia, the USA and some parts of Europe, but with remarkable effectiveness. Professor Tebello Nyokong of the Department of Chemistry , at Rhodes University, Grahamstown, is collaborating with Professor David Phillips of the Imperial College, London, as part of the AtlantIC Alliance which also involves Emory University, Atlanta and the Georgia Institute of Technology, both in Atlanta, SA.
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- Date Issued: 2001
Research portfolio
- Authors: Daphney, Robert
- Date: 2001
- Subjects: Teachers colleges -- South Africa -- Eastern Cape Competency-based education -- South Africa -- Eastern Cape Geography -- Curricula Geography -- Fieldwork -- Study and teaching Geography -- Study and teaching
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1828 , http://hdl.handle.net/10962/d1003714
- Description: This portfolio of work represents three research projects on issues related to teacher education. The research was undertaken at Dr. W.B. Rubusana College of Education over a period of three years. The first project is a situational analysis that attempts to determine whether the college is capable of meeting the challenges placed on it by the evolving South African Educational System. The key finding is that the college is not ready to embark on the changes required by the Ministry of Education chiefly because its educators and learners are seemingly not ready to embrace change. The second project is a case study that attempts to determine whether a group of 12 Senior Primary students at the college are able to interpret photographs of the local environment and as such provide evidence of their ability to be environmental educators through the medium of geography. The findings indicate that they are only able to read the photographs at a very superficial level. Their poor communication skills and their disadvantaged backgrounds seem to prevent them from achieving the level of thinking required for them to be effective environmental educators. The third project describes, analyses and evaluates a fieldwork study done with a class of Senior Primary students at the college. While the students did not achieve the necessary progression from 'look and see' to 'enquiry based' fieldwork the project was valuable in that it was an educative experience for both teacher and learner and provides evidence of the value of action research and reflective teaching.
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- Date Issued: 2001
Research projects
- Authors: Adusei-Owusu, James
- Date: 2001
- Subjects: Constructivism (Education) , Review literature , College students -- Study and teaching , Teaching -- Methods , Competency based education -- Eastern Cape (South Africa)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:1740 , http://hdl.handle.net/10962/d1003624 , Constructivism (Education) , Review literature , College students -- Study and teaching , Teaching -- Methods , Competency based education -- Eastern Cape (South Africa)
- Description: RESEARCH PROJECTS: 1 RESEARCH PROJECT ONE: A literature review: Constructivism: An alternate approach to teaching and learning. Abstract The constructivist perspectives on learning have helped enhance science educators' understanding of how students make sense of their lived experiences. Constructivism purports to be a transformation of the traditional curriculum. As such this article starts with a brief overview of behaviorism: the scientific approach to education. The main tenets underlying constructivism, how constructivism guides educators to change their classroom practice, and the implications to science teaching have been reviewed. 2 RESEARCH PROJECT TWO (Empirical study): Being Constructive: College students' learning of work and heat as aspects of the energy concept based a constructivist approach. Abstract This study is an extension of a literature review on constructivism as an alternate teaching and learning approach discussed in research project one. It is an empirical study concerning the use of a learning module based on a constructivist approach to develop pre-service student teachers' understanding of work and heat as aspects of the energy concept. The data consisted mainly of transcripts of students' interviews, written responses to questionnaires designed in the form of a worksheet, and comments from non-participant observers and students. The results seem to suggest that a carefully designed learning module based on a constructivist teaching and learning approach may be a valuable tool in developing pre-service student teachers' understanding of work and heat. 3 RESEARCH PROJECT THREE (Empirical study): A College in transition: A case study of the readiness of a college in the Eastern Cape province to implement Outcomes-Based Education in an Education Development centre. Abstract Curriculum 2005 premised on Outcomes-Based Education is the new curriculum framework for South Africa. It signifies a paradigm shift in education from the traditional 'telling-listening' relationship between the teacher and the learner to one that emphasises leamer-centred approach to the teaching process. Teachers, though recognized as crucial to the educational transformation process in the country have also being identified as ill-equipped to meet the challenges posed by Outcomes-Based Education. This study starts with a brief overview of the South African curriculum and the main tenets underlying Outcomes-Based Education. The institutional conditions and whether the lecturers at a college in the Eastern Cape province perceive the need for a change in their classroom practice were also investigated. Bearing in mind the need for further research to validate the findings of this study, positive indicators that emerged from the study suggest the readiness of the college to implement Outcomes-Based Education at the proposed Education Development Centre.
- Full Text:
- Date Issued: 2001
Review of the deep-sea anglerfishes (Lophiiformes: Ceratioidei) of southern Africa
- Authors: Anderson, M Eric , Leslie, Robin W
- Date: 2001
- Language: English
- Type: Text
- Identifier: vital:15029 , http://hdl.handle.net/10962/d1019903 , ISSN 0073-4381 , Ichthyological Bulletin of the J.L.B. Smith Institute of Ichthyology; No. 70
- Description: Deep-sea anglerfishes (Lophiiformes, Ceratioidei) of the familes Caulophrynidae, Melanocetidae, Himantolophidae, Diceratiidae, Oneirodidae, Thaumatichthyidae, Centrophrynidae, Ceratiidae, Gigantactinidae and Linophrynidae from southern Africa are reviewed since the publication of the book Smiths’ Sea Fishes (1986, 1991). Twenty-three new records of ceratioid anglerfishes are reported for the region, bringing the total to 32. No new taxa are described. The faunal area for southern African deep-sea fishes is expanded from that of Smiths’ Sea Fishes in order to include several literature records and recognize the broad distributions of these fishes through the deep-pelagic Atlantic/Indo-Pacific transit zone. Keys to all families, genera and species, as well as descriptions of all southern African specimens, are provided. The bulk of this material was collected during research cruises of South Africa’s RS AFRICANA and MEIRING NAUDE. , Rhodes University Libraries (Digitisation)
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- Date Issued: 2001
Revisiting nomenclature: 'Early Iron Age', 'First-Millennium Agriculturist', or what?
- Authors: Steele, John
- Date: 2001
- Language: English
- Type: text , Article
- Identifier: http://hdl.handle.net/11260/934 , vital:30067
- Description: As an art historian who has recently become fascinated by First-Millennium Agriculturist ceramics, I have come across several attempts at dealing with an issue of appropriate nomenclature for desigrrating this era. Conceptual frameworks are articulated using words, yet an apparent discomfort with the term Early Iron Age has seemingly not led to a consistently used altemative. I have been wondering about this and, with respect, offer my thoughts on the matter in a hope that debate will be furthered. Hereunder I utilise aspects of the KwaZulu-Natal and Eastem Cape first millennium ceramic sequence to address some significances associated with such artefacts in interpretations of the past, and then discuss some ways in which ideas of particular social contexts are embedded in language. Thereafter introduction of the term Iron Age into South African archaeology is referred to with reference to past and current usage, and advantages/disadvantages of alternatives are suggested.
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- Date Issued: 2001
Rhodes University Graduation Ceremony 2001
- Authors: Rhodes University
- Date: 2001
- Language: English
- Type: text
- Identifier: vital:8146 , http://hdl.handle.net/10962/d1007296
- Description: Rhodes University Graduation Ceremonies 1820 Settlers National Monument Friday, 6 April 2001 at 10:30; 18:00 [and] Saturday, 7 April 2001 at 10:30 , Graduation Ceremony Christian Centre, Wyse Street, East London Friday, 1 May 2001 at 18:00
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- Date Issued: 2001