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Sustainability assessment using a unit-based sustainability assessment tool: The case of three teaching departments at Rhodes University, South Africa

  • Authors: Togo, Muchaiteyi
  • Date: 2008
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/386863 , vital:68182 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/122776"
  • Description: A sustainability assessment study was performed with three teaching departments at Rhodes University – Ichthyology and Fisheries Science, Anthropology, and Accounting. The assessment used a Unit-based Sustainability Assessment Tool (USAT) and was guided by systems thinking and the ontological framework provided by critical realism. Results of the study showed that the Department of Ichthyology and Fisheries Science had a higher integration of sustainability issues in its activities than the other departments sampled, with Accounting having the lowest integration. Interviews conducted with departmental heads and content analyses of documents revealed differences in sustainability issues addressed and in approaches used in tackling them among these departments. The study is intended to inform the Mainstreaming of Environment and Sustainability in African (MESA) Universities Partnership, which promotes mainstreaming environment and sustainability in universities during the United Nations Decade of Education for Sustainable Development. The study does not provide answers to mainstreaming activities, but opens up space to debate and deliberate how to deal with the mainstreaming of sustainability in universities. It identified some of the challenges to be addressed in university-wide mainstreaming work, and affirmed the need for systems thinking in bringing about change at institutional level to extend changes taking place in individual teaching contexts.
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  • Date Issued: 2008

Synthesis and electrochemical characterisation of a near infrared absorbing oxo vanadium (IV) octapentylthio-phthalocyanine

  • Authors: Mbambisa, Gcineka , Nyokong, Tebello
  • Date: 2008
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/266008 , vital:53909 , xlink:href="https://doi.org/10.1016/j.poly.2008.06.004"
  • Description: The synthesis of an α-substituted phthalocyanine oxo vanadium(IV) 1,4,8,11,15,18,22,25-octapentathiophthalocyanine (4) which absorbs at 850 nm in dichloromethane is reported. The complex is purple in colour and becomes green on reduction. The cyclic and square wave voltammetries of the complex show five redox couples. The spectroelectrochemical data showed only ring based processes. The ring reduced species is observed at wavelengths greater than 680 nm rather than the usual 500–600 nm range typical of ring reduced phthalocyanine complexes.
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  • Date Issued: 2008

Synthesis and photophysical properties of lead phthalocyanines

  • Authors: Modibane, D.K. , Nyokong, Tebello
  • Date: 2008
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/268636 , vital:54216 , xlink:href="https://doi.org/10.1016/j.poly.2007.12.004"
  • Description: This work reports on the synthesis and photophysical parameters of tetra-and octa-substituted new lead phthalocyanines. The complexes synthesized are: 1,4-(tetraphenoxyphthalocyaninato)lead (7a), 1,4-(tetra-tert-butylphenoxyphthalocyaninato)lead (7b), 2,3-(tetraphenoxyphthalocyaninato)lead (8a), 2,3-(tetra-tert-butylphenoxyphthalocyaninato)lead (8b), 2,3-octaphenoxyphthalocyaninatolead (9a) 2,3-[octakis(4-t-butylphenoxyphthalocyaninato)]lead (9b). Photophysical properties were studied for these complexes in a dimethylsulfoxide, dimethylformamide, toluene, tetrahydrofuran and chloroform. The fluorescence spectra were different from excitation spectra due to demetallation upon excitation. High triplet quantum yields ranging from 0.70 to 0.88 (in DMSO, DMF and toluene) and low triplet lifetimes (20–50 μs in DMSO, and more than 10 μs in the rest of the solvents) were observed due to the presence of heavy atom.
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  • Date Issued: 2008

Synthesis and solvent effects on the photophysicochemical properties of novel cadmium phenoxy phthalocyanines

  • Authors: Chidawanyika, Wadzanai J U , Antunes, Edith M , Nyokong, Tebello
  • Date: 2008
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/268649 , vital:54217 , xlink:href="https://doi.org/10.1016/j.jphotochem.2007.09.020"
  • Description: The syntheses of novel cadmium phenoxy complexes; tetrakis{1,(4)-tert-butylphenoxyphthalocyaninato}cadmium(II) (5a), tetrakis{1,(4)-phenoxyphthalocyaninato}cadmium(II) (5b), tetrakis{2,(3)-tert-butylphenoxyphthalocyaninato}cadmium(II) (6a) and tetrakis{2,(3)-phenoxyphthalocyaninato}cadmium(II) (6b) are presented herein. The spectroscopic and photophysicochemical properties have also been carried out and discussed together with the influence of various organic solvents on these properties. Spectroscopic properties, i.e. ground state electronic absorption and fluorescence spectra have been found to vary as a function of substituent position on the phthalocyanine macrocycle, i.e. α-substitution versus β-substitution. The photophysical parameters are reported as well as the photodegradation and singlet oxygen quantum yields, where the complexes were found to exhibit good photostability with the production of appreciable amounts of singlet oxygen.
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  • Date Issued: 2008

Synthesis, electrochemical characterization of tetra-and octa-substituted dodecyl-mercapto tin phthalocyanines in solution and as self-assembled monolayers

  • Authors: Khene, Samson M , Geraldo, Daniela A , Togo, Chamunorwa A , Limson, Janice , Nyokong, Tebello
  • Date: 2008
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/264541 , vital:53743 , xlink:href="https://doi.org/10.1016/j.electacta.2008.08.018"
  • Description: Non-peripherally (α) tetra- (9) and octa-(7) substituted dodecyl-mercapto tin(IV) phthalocyanines were synthesized and their electrochemical behavior studied. Cyclic voltammetry and spectroelectrochemistry show ring-based reductions for 7 and 9, the former shows two ring oxidations, while the latter shows only one ring-based oxidation. The adsorption kinetics of (7) and (9) on gold electrode were investigated by electrochemical impedance spectroscopy (EIS). The equilibrium constant (K) for the adsorption and the Gibbs free energy (ΔGads) of the SAMs were evaluated based on the Frumkin isotherm.
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  • Date Issued: 2008

Synthesis, photochemical and photophysical properties of gallium and indium phthalocyanine derivatives

  • Authors: Chauke, Vongani Portia
  • Date: 2008
  • Subjects: Phthalocyanines , Photochemotherapy , Electrochemistry , Gallium , Indium
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4375 , http://hdl.handle.net/10962/d1005040 , Phthalocyanines , Photochemotherapy , Electrochemistry , Gallium , Indium
  • Description: The syntheses of octasubstituted and unsusbstitituted Gallium(III) chloride and indium(III) chloride phthalocyanines (GaPc and InPc), their photophysical, photochemical and nonlinear optical parameters are hereby presented. The photocatalytic oxidation of 1-hexene using the synthesized GaPc and InPc complexes as well as electrochemical characterization is also presented in this thesis. Fluorescence quantum yields do not vary much among the four Ga complexes, except for complex 21c; therefore it was concluded that the effect of substituents is not significant among them. Solvents however, had an effect on the results. Lower Φ[subscript F] values were obtained in low viscosity solvents like toluene, relative to highly viscous solvents, such as DMSO. The triplet quantum yields were found to be lower in DMSO than in DMF and toluene. The rate constants for fluorescence, intersystem crossing and internal conversion as well as fluorescence and triplet lifetimes are reported. Photodegradation and singlet oxygen quantum yields have also been reported. There was no clear correlation between the latter parameters. It was however established that the four gallium MPcs were stable, within the allowed stability range for phthalocyanines. High quantum yields of triplet state (Φ[subscript T] ranging from 0.70 to 0.91 in dimethysulfoxide, DMSO) and singlet oxygen generation (Φ[subscript greek capital letter delta], ranging from 0.61 to 0.79 in DMSO) were obtained. Short triplet lifetimes 50 to 60 μs were obtained in DMSO). Calculated non-linear parameters of these complexes are compared with those of the corresponding GaPc derivatives and tetrasubstituted GaPc and InPc complexes. The optical limiting threshold intensity (I[subscript lim]) values for the InPc and GaPc derivatives were calculated and compared with those of corresponding tetrasubstituted InPc and GaPc complexes. The octasubstituted were found to be better optical limiters. Photocatalytic oxidation of 1-hexene by GaPc (21a-c) and InPc (22a-c) derivatives is also presented. The photocatalytic oxidation products for 1-hexene were 1,2- epoxyhexane and 1-hexen-3-ol. The % conversion values of 1-hexene and % selectivity of 1,2-epoxyhexane were generally higher for InPc derivatives. Even though InPc derivatives showed better photocatalytic results than GaPc derivatives, the former were less stable relative to the latter. Both type I and type II mechanism were implicated in the photocatalysis mechanism.
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  • Date Issued: 2008

Synthesis, photophysical and photochemical studies on long chain zinc phthalocyanine derivatives

  • Authors: Ogunsipe, Abimbola , Durmus, Mahmut , Atilla, Devrim , Gürek, Ayşe Gül , Ahsen, Vefa , Nyokong, Tebello
  • Date: 2008
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/266019 , vital:53910 , xlink:href="https://doi.org/10.1016/j.synthmet.2008.06.007"
  • Description: The synthesis and characterization of 2,9,16,23-chloro-3,10,17,24-triethyleneoxysulphanylphthalocyaninato zinc(II) (CTESZnPc) is described. The photophysics and photochemistry of CTESZnPc and those of tetrakis(triethyleneoxysulphanyl)zinc phthalocyanine (TTESZnPc) and octakis(triethyleneoxysulphanyl)zinc phthalocyanine (OTESZnPc), are presented and compared with those of unsubstituted zinc phthalocyanine (ZnPc). The presence of triethyleneoxysulphanyl substituents on the ZnPc ring gave rise to higher values of singlet oxygen (ΦΔ) and photodegradation (ΦPd) quantum yields in DMF. However, TTESZnPc, OTESZnPc and CTESZnPc are less fluorescent than ZnPc, judging from their fluorescence quantum yield (ΦF) values. Fluorescence was lower in toluene than in DMF due to aggregation in the former solvent. Triplet quantum yield (ΦT) values were found to increase with the presence of substituents on the ZnPc ring, while triplet lifetimes (τT) were found to vary linearly with the logarithms of solvent viscosities. The fluorescences of the substituted ZnPc complexes were effectively quenched by benzoquinone (BQ), and the quenching data analyzed by the Stern–Volmer equation. The Stern–Volmer constants and the diffusion-controlled bimolecular rate constants were calculated.
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  • Date Issued: 2008

Synthesis, photophysics and electrochemical study of tin macrocycles

  • Authors: Khene, Mielie Samson
  • Date: 2008
  • Subjects: Electrochemistry , Photochemistry , Phthalocyanines , Macrocyclic compounds , Spectrum analysis
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4376 , http://hdl.handle.net/10962/d1005041 , Electrochemistry , Photochemistry , Phthalocyanines , Macrocyclic compounds , Spectrum analysis
  • Description: Three non-peripherally substituted tin(IV) macrocylic compounds, octahexylphthalocyaninato dichlorotin(IV) (35a), octahexyltetrabenzo-5,10,15-triazaporphyrinato dichlorotin(IV) (35b) and octadecylphthalocyaninato dichlorotin(IV) (35c) were synthesized and their photophysical and electrochemical behaviour studied. Complex (35b), containing a CH group in place of one of the aza nitrogen atom of the phthalocyanine core, shows a split Q band due to its lower symmetry. The triplet state quantum yields were found to be lower than would be expected on the basis of the heavy atom effect of tin as the central metal for phthalocyanine derivatives (35a and 35c). In contrast, (35b) shows a triplet quantum yield ΦT = 0.78. The triplet state lifetimes were solvent dependent, and were higher in THF than in toluene. Cyclic voltammetry and spectroelectrochemistry of the complexes revealed only ring based redox processes. This thesis also reports on the microwave syntheses of tetrasulphonated tin phthalocyanine and tetrasulphonated tin α,β,γ-tetrabenzcorrole. The latter was only formed at low ratios (< 1:8) of 4-sulfophthalic acid to urea. Both complexes are aggregated in aqueous media, but can be partly or fully disaggregated by the addition of Triton X-100. The SnTSTBC complex has lower triplet life times and yields, while binding constant and quenching (of bovine serum albumin) constant are lower for SnTSTBC, compared to SnTSPc. Finally Non-peripherally (α) tetra- (40) and octa-(38a) substituted dodecyl-mercapto tin(IV) phthalocyanines where synthesized and the electrochemical behavior studied. Cyclic voltammetry and spectroelectrochemistry show ring-based reductions for (38a) and (40); the former shows two ring oxidations, while the latter shows only one ring based oxidation. The adsorption kinetics of (38a) and (40) on a gold electrode have been investigated by electrochemical impedance spectroscopy (EIS). The equilibrium constant (K) for the adsorption and the Gibbs free energy ΔG(ads) of the self-assembled monolayer (SAMs) were evaluated based on the Frumkin isotherm. The interaction factor between adsorbate –adsorbate molecules is also discussed.
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  • Date Issued: 2008

Synthetic, spectrometric and computer modelling studies of novel ATP analogues

  • Authors: Gxoyiya, Babalwa Siliziwe Blossom
  • Date: 2008
  • Subjects: Spectrum analysis Tuberculosis -- Treatment Chemotherapy Adenosine triphosphate Adenosine triphosphate -- Synthesis Adenosine triphosphate -- Computer simulation Adenosine triphosphate -- Spectrometric imaging Glutamine synthetase Tuberculosis -- Chemotherapy
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:4386 , http://hdl.handle.net/10962/d1005051
  • Description: This study has been concerned with the design and synthesis of A TP analogues with the potential to act as inhibitors of glutamine synthetase - a novel target for therapeutic intervention in the treatment of tuberculosis. Using a structural -analogy approach, various 3-indolylalkanoic acid, benzimidazole and pyrazolo[3,4-dJpyrimidine derivatives have been prepared and characterized. Alkylation of the heterocyclic bases using 4-(bromomethyl)-2,2-dimethyl-1 ,3-d ioxolane, 2-(bromomethoxy)ethyl acetate and 2-(chloroethoxy)ethanol in the presence of either NaH or BulOK afforded the corresponding N-alkylated derivatives of benzimidazole and 4-aminopyrazolo[3,4-dJpyrimidine (4-APP). Similar reactions with 3-indo lylalkanoic esters resulted in O-alkyl cleavage with the formation of new esters. Alkylation of benzimidazole with allyl bromide, 4-bromobutene and 2-methylbut-2-ene has also been shown to afford the corresponding l-alkenylbenzimidazoles in moderate to excellent yield (43-96%). Subsequent oxidation of these products using CTAP, gave the dihydroxy derivatives in poor to good yields (26-77%). Phosphorylation of various hydroxy derivatives of benzimidazole and 4-APP has been achieved using diethyl chlorophosphate to afford the corresponding monophosphate and 1,2-diphosphate esters. Glycosylation of each of the heterocyclic bases has been successfully achieved using 1,2,3,4,6-penta-O-acetyl-D-glucopyranose and SnCl4 in acetonitri le, while methanolysis of the resulting tetraacetates, using methanolic NaOMe, afforded the hydroxy derivatives in good yield (50-70%). Various 1- and 2-dimensional NMR spectroscopic methods (e.g., IH, 13C, lip, COSY, HSQC and HMBC) have been used to confirm the structures of the synthesized A IP analogues. The application of NMR prediction programmes has been explored, permitting assessment of their agreement with the experimental data and confirmation of assigned structures. High-resolution electron impact (EI) mass spectrometric data have been used to explore the mass fragmentation pathways exhibited by selected derivatives, and certain common fragmentations have been identified. Molecular modelling of selected products as potential glutamine synthetase ligands has been performed on the Accelrys Cerius2 platform, and interactive receptor-ligand docking studies have been conducted using the Ligand-Fit module. These studies have revealed possible hydrogen-boding interactions between the selected analogues and various amino acid residues in the glutamine synthetase active site.
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  • Date Issued: 2008

Taxation and electronic commerce

  • Authors: Stelloh, Marcus M , Stack, Elizabeth M
  • Date: 2008
  • Subjects: To be catalogued
  • Language: English
  • Type: Conference paper
  • Identifier: vital:6066 , http://hdl.handle.net/10962/d1004611
  • Description: Transactions conducted using the Internet have expanded dramatically in the past few years and countries and their governments have become concerned about the consequences that electronic commerce may have on their tax revenues. Because of this many organisations and inter-governmental agencies have met to try to design a solution that will be compatible with the systems of the various countries and achieve tax neutrality. A number of proposals were made and discussed to try to design a fair and efficient e-tax system. The proposed system that is ultimately adopted must consider different tax bases and systems in order to achieve this. In this research the impact of e-commerce on the imposition of income tax was briefly referred to and four different proposals for levying value-added tax or sales tax were analysed in order to compare the advantages and disadvantages of each and to determine which system would most adequately address the needs of e-commerce. Certain modifications and additions to the proposed systems have been suggested in order to satisfy the specific needs of the South African tax system, while still taking other countries’ tax systems into account. Using Amazon.com Inc. and Skype Technologies South Africa Limited as examples, it is demonstrated how the new amended system will work. It was found that the proposed systems and the system adapted to meet the South African needs would, with a few relatively minor changes to the Value-Added Tax legislation, be suitable for the purposes of imposing value-added tax on e-commerce transactions.
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  • Date Issued: 2008

Teachers' perceptions of participative management in a primary school in Namibia

  • Authors: Kambonde, Samuel Angaleni
  • Date: 2008
  • Subjects: Education, Elementary -- Namibia Teachers -- Namibia School management and organization -- Namibia Educational leadership -- Namibia
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1795 , http://hdl.handle.net/10962/d1003680
  • Description: Participative management, a key theme in contemporary management literature, is one of the central aims of the decentralization policy in Namibian education. Current perceptions of participative management on the part of teachers in Namibia are therefore of topical interest. This study set out to explore such perceptions among teachers in a Namibian primary school. The study is an interpretive case study focusing on six individual teachers’ understanding and experience of participative management within their place of work, a primary school in the Oshikoto region of Namibia. Semi-structured interviews, observation and document analysis were used to gather data. The study revealed a strong sense of commitment among the respondents to participative management and its accompanying practices, such as shared decision making and broad stakeholder involvement. Participative management was implemented chiefly through a committee structure for school organisation and government. Respondents also highlighted challenges facing participative management, such as the persistence of autocratic leadership, conflicts of interest in decision making, laziness and unwillingness among staff members, and a lack of understanding among parents concerning their role in the schooling of their children. HIV/AIDS was also seen to pose challenges to the free and frequent participation of stakeholders. The chief recommendation arising from these findings is that school leaders and managers’ understanding of tenets of participative management, such as site-based management and democratic management approaches, requires improvement and development.
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  • Date Issued: 2008

Teaching reading in grade 4 Namibian classrooms : a case study

  • Authors: Mutenda, Josephine
  • Date: 2008
  • Subjects: Literacy -- Study and teaching (Elementary) -- Namibia English language -- Study and teaching (Elementary) -- Namibia Reading (Elementary) -- Namibia Second language acquisition
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1797 , http://hdl.handle.net/10962/d1003682
  • Description: Literacy is currently a topic of great concern in Namibia. Learners in this country have difficulty in reading and writing, and are often functionally illiterate. This study focuses on the beliefs, experiences and practices of teachers of reading in English to second language learners in Grade 4. Grade 4 is the transitional grade from mother tongue to English as the medium of instruction. The switch to English makes teaching reading in that language especially challenging. The study is structured according to the case study mode of enquiry, with the target respondents comprising Grade 4 teachers. Classroom observation, interviews and document analysis were used as means of collecting data. The main findings revealed that beliefs and experience had an impact on the way in which reading was taught in this study. It emerged that the teachers’ childhood experiences of literacy and learning to read are perpetuated in their beliefs, their attitudes, their basic conceptualization of reading and their current practices, all of which directly affect the children in their classes. Although the teachers’ professional training also had some influence on their teaching methods, neither of the two teachers interviewed had received much in-service support on how to teach reading, and they depended to a large extent on their recall of how they had learned to read themselves. Both teachers were taught in a traditional, teacher-centered way, involving phonics, rote-learning and drilling. Because they see themselves as competent readers, they believe that these approaches were effective and worth sustaining. Tentative recommendations arising from analysis of the data indicate possible areas for improvement in the teaching of reading, and offer guidelines to help teachers cope with the challenge.
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  • Date Issued: 2008

Technical constraints to smallholder agriculture: case study of Nkonkobe Municipality, Eastern Cape, South Africa

  • Authors: Pote, Peter Paul Takawira
  • Date: 2008
  • Subjects: Farms, Small -- South Africa -- Eastern Cape , Farms -- South Africa -- Technology , Agricultural productivity -- South Africa -- Eastern Cape , Agriculture -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , MSc Agric (Agricultural Economics)
  • Identifier: vital:11193 , http://hdl.handle.net/10353/84 , Farms, Small -- South Africa -- Eastern Cape , Farms -- South Africa -- Technology , Agricultural productivity -- South Africa -- Eastern Cape , Agriculture -- South Africa -- Eastern Cape
  • Description: Using data drawn from a sample of 80 farmers in the Kat River valley, this thesis presents the results of an assessment of the technical constraints affecting smallholder development and their implications for market access. A review of the relevant literature on the smallholder farm sector, technical change and technical constraints affecting smallholder farmers along with an overview of the agricultural marketing environment in South Africa has been presented. A critical review of the theoretical framework for consideration of technical change in agricultural development, with particular attention to the induced innovation model was undertaken. General information on the institutional set up was obtained by open-ended interviews of community leaders and focus groups. These interviews supplemented information obtained through literature study and document analysis. The other method of data collection employed was the single-visit household survey using structured questionnaires. The demographic and socio-economic characteristics of the surveyed farmers are described in this study. The selection process of the variables influencing market access was done by employing correlation and logistic regression analyses. Correlation analysis was conducted to ascertain the relationship among variables to find out the extent to which they mirror theory or intuition regarding their causation to constraints influencing market access. The logistic model was employed in the step-wise manner using each of key production inputs as response variables sequentially. On the basis of a binary logistic model, it can be concluded that the farmers still operate under a number of technical constraints. The most influential constraints are information, asset ownership, value of agricultural production and extension assistance. The study reflects the previous findings in South Africa that the legacy of apartheid continues to negatively impact on its agricultural economy. Key words: Technical Constraints, Technical Change,Market Access, Smallholder Farmers, Agricultural Development, Induced Innovation Model, Kat River Valley, Correlation analysis, Theoretical framework and Binary Logistic Model
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  • Date Issued: 2008

Temperature dependence of the HartRAO pointing model

  • Authors: Copley, Charles Judd
  • Date: 2008
  • Subjects: Astronomical instruments , Observatories -- South Africa , Telescopes , Astronomical observatories , Astronomy -- Data processing , Antennas (Electronics)
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5491 , http://hdl.handle.net/10962/d1005277 , Astronomical instruments , Observatories -- South Africa , Telescopes , Astronomical observatories , Astronomy -- Data processing , Antennas (Electronics)
  • Description: This thesis investigates control aspects of the Hartebeeshoek Radio Astronomy Observatory (HartRAO) antenna. The installation of a new 22 GHz receiver has required the pointing accuracy to be improved to less than 4 mdeg. The effect of thermal conditions on the the HartRAO antenna pointing offset is investigated using a variety of modelling techniques including simple geometric modelling, neural networks and Principal Component Analysis (PCA). Convincing results were obtained for the Declination pointing offset, where applying certain model predictions to observations resulted in an improvement in Declination pointing offset from 5.5 mdeg to 3.2 mdeg (≈50%). The Right Ascension pointing model was considerably less convincing with an improvement of approximately from 5.5 mdeg to 4.5 mdeg (≈20%) in the Right Ascension pointing offset. The Declination pointing offset can be modelled sufficiently well to reduce the pointing offset to less than 4 mdeg, however further investigation of the underlying causes is required for the Right Ascension pointing offset.
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  • Date Issued: 2008

Temporal and spatial variability in stable isotope ratios of SPM link to local hydrography and longer term SPM averages suggest heavy dependence of mussels on nearshore production

  • Authors: Hill, Jaclyn M , McQuaid, Christopher D , Kaehler, Sven
  • Date: 2008
  • Language: English
  • Type: text , Article
  • Identifier: vital:6969 , http://hdl.handle.net/10962/d1012034
  • Description: Temporal changes in hydrography affect suspended particulate matter (SPM) composition and distribution in coastal systems, potentially influencing the diets of suspension feeders. Temporal variation in SPM and in the diet of the mussel Perna perna, were investigated using stable isotope analysis. The δ13C and δ15 N ratios of SPM, mussels and macroalgae were determined monthly, with SPM samples collected along a 10 km onshore–offshore transect, over 14 months at Kenton-on-Sea, on the south coast of South Africa. Clear nearshore (0 km) to offshore (10 km) carbon depletion gradients were seen in SPM during all months and extended for 50 km offshore on one occasion. Carbon enrichment of coastal SPM in winter (June–August 2004 and May 2005) indicated temporal changes in the nearshore detrital pool, presumably reflecting changes in macroalgal detritus, linked to local changes in coastal hydrography and algal seasonality. Nitrogen patterns were less clear, with SPM enrichment seen between July and October 2004 from 0 to 10 km. Nearshore SPM demonstrated cyclical patterns in carbon over 24-h periods that correlated closely with tidal cycles and mussel carbon signatures, sampled monthly, demonstrated fluctuations that could not be correlated to seasonal or monthly changes in SPM. Macroalgae showed extreme variability in isotopic signatures, with no discernable patterns. IsoSource mixing models indicated over 50% reliance of mussel tissue on nearshore carbon, highlighting the importance of nearshore SPM in mussel diet. Overall, carbon variation in SPM at both large and small temporal scales can be related to hydrographic processes, but is masked in mussels by long-term isotope integration.
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  • Date Issued: 2008

Texts, practices and student learning: a view from the South

  • Authors: Boughey, Chrissie
  • Date: 2008
  • Language: English
  • Type: Article
  • Identifier: vital:6085 , http://hdl.handle.net/10962/d1008482
  • Description: This article uses ‘close-up’ ethnographic research to provide an account of students’ engagement with learning in a South African university. Broadly based on Halliday’s (1973, 1978, 1994) understanding of texts resulting from contexts, the account challenges dominant constructions of the problems students encounter as stemming from the use of inappropriate ‘approaches’ to learning, the lack of ‘study’ and other skills or problems with proficiency in areas such as writing or language and shows how students’ unfamiliarity with the context of the university leads them to draw on ‘other’ contexts in order to engage with the texts they must read, write and listen to in the course of their studies. This drawing on ‘other’ contexts then results in the texts produced by students, and the practices which give rise to those texts, being inappropriate to the context of the university. Although the research on which the article is based took place in South Africa, it is argued that the theoretical perspective it provides has relevance across other contexts given the increasingly diverse student bodies which characterize higher education across the globe.
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  • Date Issued: 2008

That-has-been a discussion on the body cast as that which fixes a subject in time, in relation to notions surrounding the photograph

  • Authors: Maree, Christine Fae
  • Date: 2008
  • Subjects: Barthes, Roland. Camera Lucida Photography, Artistic Photography -- Philosophy Photographic criticism
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2412 , http://hdl.handle.net/10962/d1002208
  • Description: Much like a photograph, a casts creates a replica of its referent, thereby immobilising the subject in time. While the subject continues in time and hence ages and inevitably dies the replica does not. With this basic notion of fixing a subject, I have built an argument to contextualise my sculptures, which are made using casts of elderly people. In this discussion I have looked at my works through the ideas of different theorists. The main theorist I have cited is Roland Barthes, specifically with regards to his notion of the photograph as discussed in his book Camera Lucida. I have also referenced three particular artists: Rachel Whiteread, Diane Arbus and Churchill Madikida, as I have found each of their works relate to my work in various ways, creating a different reading from each viewpoint.
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  • Date Issued: 2008

The "other" Africans : re-examining representations of sexuality in the work of Nicholas Hlobo and Zanele Muholi

  • Authors: Makhubu, Nomusa
  • Date: 2008
  • Subjects: Hlobo, Nicholas Muholi, Zanele Women in art Photography, Artistic Homosexuality in art Sex in art Performance art Art, African
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2410 , http://hdl.handle.net/10962/d1002206
  • Description: Nicholas Hlobo, a sculptor and performance artist, and Zanele Muholi, a photographer and activist, explore different ways of representing sexuality, particularly homosexuality. It is extremely difficult to discuss African sexuality in light of the stain of colonial attitudes that have exoticised and ascribed hypersexuality to African bodies. Moreover, sexuality is often not discussed in the construction of so-called African traditions and this has contributed to rendering African-ness as an exclusive identity. Tensions within and between categories of African-ness are compounded by constituted regulations. For example, Hlobo investigates the obligation of circumcision which seems to contrast the lifestyle and contexts in which he works and resides, and Muholi represents the existence of homosexual and transgender relations, even within conservative categories. The visual imagery of these two artists investigates the boundaries set by different social constructs. These set boundaries have also affected crimes against bisexual, transgender and homosexual individuals, which are reaching an alarming rate. Hlobo questions the validity of structures that marginalise homosexual individuals through drawing attention to the ambivalence of certain statutes. Muholi seeks to publicise the injustices imposed upon homosexual individuals in order to demonstrate the weight of that crisis. Although the South African legal system condones liberated expressions of sexual identity, due to social prejudices homosexual individuals are still treated as if they are not entitled to basic human rights. As a result, hate-crimes are not reported, and when they are they are not taken seriously. Hlobo and Muholi not only bring these issues to light, but also point out the dilemma inscribed in the social and political history of (South) Africa with regards to collective and individual identities. This thesis seeks to provide an analysis of the visual language used by Hlobo and Muholi to subvert the notion that homosexuality is “un-African” and to complicate concepts of gender, sexuality and identity.
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  • Date Issued: 2008

The African Peer Review Mechanism : towards Africa's governance audit

  • Authors: Molete, Nathan Teboho
  • Date: 2008
  • Subjects: African Peer Review Mechanism New Partnership for Africa's Development Peer review -- Africa Auditing -- Africa Africa -- Politics and government -- 1960-
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2867 , http://hdl.handle.net/10962/d1007681
  • Description: The concept of accountability has grown to become an integral part of a broader political and socio-economic transformation. Closely associated to it is the concept of "auditing" which has established itself as a main driving force of accountability and a core means of delivering it. The extent of the rise and expansion of "auditing" has subsequently come to influence every aspect of modern life and this has led to a situation in which practices have had to adapt to the principles of "auditing" processes. Auditing has become prevalent in both the public and private spheres and this impact has far reaching consequences. The concept of "auditing" is evident in the African Peer Review Mechanism (APRM) and is central to its review process. This thesis focuses on the concept of "auditing" in order to illustrate how the APRM has borrowed and applied insights from other disciplinary practices so as to enhance an understanding of accountability and transparency as features of "good governance" and to explicate how these concepts are conceived within the framework of the New Partnership for Africa's Development (NEPAD). It also clarifies the relationship that exists between "peer review" and "auditing" and argues that rather than being considered as two poles marked by distance from each other "auditing" and "peer review" are closely related and mutually constitutive.
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  • Date Issued: 2008

The African reception of global media:

  • Authors: Strelitz, Larry N , Boshoff, Priscilla A
  • Date: 2008
  • Language: English
  • Type: text , book
  • Identifier: http://hdl.handle.net/10962/143527 , vital:38254 , ISBN 9781473971752 , https://books.google.co.za/books?id=pfRcCwAAQBAJanddq=The+African+Reception+of+Global+Mediaandlr=andsource=gbs_navlinks_s
  • Description: This chapter engages debates concerning the impact of global media on local youth audiences in Africa. Recognizing the profound rootedness of media consumption in everyday life, the chapter specifically examines the way selected South African youth audiences, differentially embedded in their particular economic and ideological formations, use local and global media texts as part of their ongoing attempts to make sense of their lives.
  • Full Text:
  • Date Issued: 2008
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