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Strategies used by subject advisors and facilitators to support lesson planning with an environmental learning focus : a case study of the Eastern Cape Neep-Get cluster

  • Authors: Mbambisa, Nomaledi Peggy
  • Date: 2005
  • Subjects: Educational change -- South Africa Education and state -- South Africa Environmental education -- South Africa Competency-based education Curriculum change -- South Africa
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1926 , http://hdl.handle.net/10962/d1007586
  • Description: Over the past ten years, South Africa has undergone substantial changes, following the advent of democracy. Key amongst these changes being the transformation of educational policy. These policy changes have introduced new structural frameworks within which we operate (including myself as a subject advisor) and new roles for educators. These policy changes affect all the levels of the education system, and have an impact at school level, where teachers are now responsible for learning programme development (including a focus on lesson planning). Lesson planning in an outcomes-based education framework is a challenging aspect of policy implementation. South Africa is faced with the challenges associated with policy change and implementation. The role of the subject advisors and facilitators who support the teachers to make sense of the curriculum is crucial, as they provide the interface between policy and practice. They are the people who work most with teachers, and have a responsibility for curriculum implementation. This study aimed to explore the strategies which are used by subject advisors and facilitators to support teachers develop lesson plans with an environmental learning focus. A qualitative case study was conducted in which I looked at how the support processes were provided by the subject advisors and facilitators in the Eastern Cape in particular the NEEP-GET cluster in the Makana district. The study employed a range of data producing techniques such as questionnaires, interviews, document analysis and observation. The data was analysed to report the findings. The research indicates that some strategies are used to provide curriculum and pedagogical support and guidance, but that these are superficially treated and others have not been attempted at all. This therefore shows that further growth in this area is possible amongst the subject advisors. Recommendations relevant to both the subject advisors and the Department of Education so as to enhance the support processes and professional development of subject advisors have been made.
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  • Date Issued: 2005

Stress, coping resources and adjustment of married mothers in the teaching profession

  • Authors: Nell, Reinette Deidre
  • Date: 2005
  • Subjects: Women teachers -- Life skills assessment -- South Africa , Work and family -- South Africa -- Psychological aspects , Life skills , Stress (Psychology)
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:9851 , http://hdl.handle.net/10948/387 , Women teachers -- Life skills assessment -- South Africa , Work and family -- South Africa -- Psychological aspects , Life skills , Stress (Psychology)
  • Description: The changes that have taken place in the South African educational system over the past few years have placed teachers under increasing stress. While abundant overseas literature is available regarding teacher stress, limited studies have focused specifically on South African samples. Female teachers, and working mothers, often experience additional stressors to men. Studies on women’s health have received little attention in comparison with the magnitude of research conducted on men’s health. The aim of the current study was to explore and describe the stress, coping resources and adjustment of married mothers in the teaching profession, and to explore and describe the patterns of stress and coping resources of these women. A non-experimental, exploratory descriptive study was employed. A biographical questionnaire and three paper-and-pencil measures, namely the Experience of Work and Life Questionnaire, the Coping Resources Inventory and the Personal, Home, Social and Formal Relations Questionnaire, were administered to 31 full-time primary school teachers who are married mothers of dependent children under the age of 14 years. A non-probability convenience sampling technique was employed. Descriptive statistics and cluster analysis were used in the data analysis. The results of the WLQ for this sample indicated that the mean score for the total level of stress fell within the high range, but with regards to the mode, the majority of the participants had average scores. The results of the CRI indicated an average level of coping resources for the present sample. The sample scored slightly above average on seven of the eleven components of the adjustment areas of the PHSF and slightly below average on the other four components. The participants in cluster one had average levels of stress and an average level of coping resources. The participants in cluster two scored very high levels of stress and average levels of coping resources. The participants in cluster three had very high levels of stress and low levels of coping resources. Suggestions were made for future research involving the stress, coping resources and adjustment of married mothers in the teaching profession. Finally, the limitations as well as the value of the research were outlined.
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  • Date Issued: 2005

Stress-inducible protein 1: a bioinformatic analysis of the human, mouse and yeast STI1 gene structure

  • Authors: Aken, Bronwen Louise
  • Date: 2005
  • Subjects: Molecular chaperones , Proteins -- Analysis , Heat shock proteins , Bioinformatics , Genetics -- Data processing
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:3990 , http://hdl.handle.net/10962/d1004049 , Molecular chaperones , Proteins -- Analysis , Heat shock proteins , Bioinformatics , Genetics -- Data processing
  • Description: Stress-inducible protein 1 (Sti1) is a 60 kDa eukaryotic protein that is important under stress and non-stress conditions. Human Sti1 is also known as the Hsp70/Hsp90 organising protein (Hop) that coordinates the functional cooperation of heat shock protein 70 (Hsp70) and heat shock protein 90 (Hsp90) during the folding of various transcription factors and kinases, including certain oncogenic proteins and prion proteins. Limited studies have been conducted on the STI1 gene structure. Thus, the aim of this study was to develop a comprehensive description of human STI1 (hSTI1), mouse STI1 (mSTI1), and yeast STI1 (ySTI1) genes, using a bioinformatic approach. Genes encoded near the STI1 loci were identified for the three organisms using National Centre for Biotechnology Information (NCBI) MapViewer and the Saccharomyces Genome Database. Exon/intron boundaries were predicted using Hidden Markov model gene prediction software (HMMGene) and Genscan, and by alignment of the mRNA sequence with the genomic DNA sequence. Transcription factor binding sites (TFBS) were predicted by scanning the region 1000 base pairs (bp) upstream of the STI1 orthologues’ transcription start site (TSS) with Alibaba, Transcription element search software (TESS) and Transcription factor search (TFSearch). The promoter region was defined by comparing the number, type and position of TFBS across the orthologous STI1 genes. Additional putative TFBS were identified for ySTI1 by searching with software that aligns nucleic acid conserved elements (AlignACE) for over-represented motifs in the region upstream of the TSS of genes thought to be co-regulated with ySTI1. This study showed that hSTI1 and mSTI1 occur in a region of synteny with a number of genes of related function. Both hSTI1 and mSTI1 comprised 14 putative exons, while ySTI1 was encoded on a single exon. Human and mouse STI1 shared a perfectly conserved 55 bp region spanning their predicted TSS, although their TATA boxes were not conserved. A putative CpG island was identified in the region from -500 to +100 bp relative to the hSTI1 and mSTI1 TSS. This region overlapped with a region of high TFBS density, suggesting that the core promoter region was located in the region approximately 100 to 200 bp upstream of the TSS. Several conserved clusters of TFBS were also identified upstream of this promoter region, including binding sites for stimulatory protein 1 (Sp1), heat shock factor (HSF), nuclear factor kappa B (NF-kappaB), and the cAMP/enhancer binding protein (C/EBP). Microarray data suggested that ySTI1 was co-regulated with several heat shock proteins and substrates of the Hsp70/Hsp90 heterocomplex, and several putative regulatory elements were identified in the upstream region of these co-regulated genes, including a motif for HSF binding. The results of this research suggest several avenues of future experimental work, including the confirmation of the proposed core promoter, upstream regulatory elements, and CpG island, and the investigation into the co-regulation of mammalian STI1 with its surrounding genes. These results could also be used to inform STI1 gene knockout experiments in mice, to assess the biological importance of mammalian STI1.
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  • Date Issued: 2005

Students’ engagement with learning theory

  • Authors: Schudel, Ingrid J
  • Date: 2005
  • Language: English
  • Type: Article
  • Identifier: vital:6093 , http://hdl.handle.net/10962/d1008615
  • Description: This paper reflects on a module on ‘Teaching and Learning Interactions’, presented as part of the Rhodes University Advanced Certificate in Education (Environmental Education).The module is designed to help students use theoretical logic to enhance (not replace) their practical logic of how teaching and learning takes place. Data was analysed from three teaching and learning activities in the module. After the first participatory activity on water and sanitation, students narrated what teaching and learning had taken place using language available from their prior experiences. In a second activity students were introduced to explanations of learning, provided by learning theorists. In the third activity students analysed a case study, using a variety of questions relating to teaching and learning. They then had to consider these same questions in the light of a participatory on-course teaching and learning activity. The paper reflects on how students have used understandings of the nature of reality, the construction of knowledge, the use of language, situated learning, action competence and social change, in order to narrate their teaching and learning experiences on the ACE(EE) course. Through this, the paper trials a reflexive approach to the teaching of learning theory in environmental education.
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  • Date Issued: 2005

Study of the skincalm filling process at Aspen Pharmacare applying some six sigma principles

  • Authors: Marx, Johannes
  • Date: 2005
  • Subjects: Ointments -- Packaging , Six sigma (Quality control standard)
  • Language: English
  • Type: Thesis , Masters , MTech
  • Identifier: vital:10369 , http://hdl.handle.net/10948/184 , Ointments -- Packaging , Six sigma (Quality control standard)
  • Description: Aspen Pharmacare is listed on the Johannesburg Securities Exchange South Africa (JSE) and is Africa’s largest pharmaceutical manufacturer. The company is a major supplier of branded pharmaceutical and healthcare products to the local and selected international markets. For decades, Aspen has manufactured a basket of affordable, quality, and effective products for the ethical, generic over-the-counter (OTC) and personal care markets. Aspen is also the leading supplier of generic medicines to the public sector, providing comprehensive coverage of the products on the Essential Drug List. Aspen continues to deliver on its commitment toward playing a role in social responsibility diseases such as HIV/AIDS, tuberculosis and malaria. In August 2003 Aspen developed Africa’s first generic anti-retroviral drug, namely Aspen-Stavudine. Aspen’s manufacturing facilities are based in Port Elizabeth (PE) and East London. Aspen has recently completed an Oral Solid Dosage (OSD) manufacturing facility worth approximately R150 million in PE. The Group manufactures approximately 20 tons of product daily and in excess of 400 tons of solid dosage pharmaceuticals, which equates to more than 2 billion tablets. In addition, more than 3 million litres of liquid pharmaceuticals and over 200 tons of pharmaceutical creams and ointments are produced per year [1]. Aspen excels at delivering quality products and services, exceeding customer expectations, complying with international standards in an environment that cultivates technical expertise and innovation. Following this philosophy through to the shop floor areas mean that there are always initiatives in continuous production improvement. One of these improvement projects introduced is called Six Sigma. 8 Ten members of the staff, selected from different expertise fields in the company were trained in Six Sigma. Knowledge gained from the two week training course were applied to different areas in the factory using Six Sigma principles. This dissertation focuses on the study undertaken in one of production areas, namely the filling process of the ointments and creams at the Aspen Port Elizabeth facility.
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  • Date Issued: 2005

Study South Africa

  • Authors: International Education Association of South Africa (IEASA) , Kishun, Roshen
  • Date: 2005
  • Subjects: Education, Higher -- South Africa , Education and globalization -- South Africa Student mobility -- Africa International education -- South Africa Education, Higher -- International cooperation , Universities and colleges -- South Africa , Technical Institutes -- South Africa , Vocational guidance -- South Africa
  • Language: English
  • Type: text , book
  • Identifier: http://hdl.handle.net/10962/65344 , vital:28751 , ISBN 0123218931
  • Description: [Message from the President of IEASA, Dr Roshen Kishun]: We salute the thousands of South Africans From diverse racial backgrounds who 50 years ago put forward their vision, encapsulated in the Freedom Charter, to keep doors of education open. As we celebrate the 50th anniversary of this historic event we are aware of the Foundations laid then to allow us to reconnect to the world. In choosing “lessons in diversity' as the theme For the Sth edition of Study South Africa we support the need For South African higher education to keep its doors open in meeting the development challenges of Africa. The year 2005 has been described as critical For Africa because of a number of Factors that have come together. These include the New Partnership For Africa’s Development which spells out action plans to tackle some of the more intractable problems that Africa Faces, the Formation of the African Union with clear guidelines For governance and peace, and the Pan-African Parliament which promotes the concept of working together to solve the continent's problems. The launch of the Southern African Regional Universities Association in early 2005 by 45 of the region’s vice-chancellors recognised that the excellence and sustainability of university education, research and development will be a leading contributor to Future growth and poverty alleviation. Despite the tides of limited resources, external demands and internal policy challenges, the vice-chancellors were unequivocally committed to advancing the development agenda of higher education on the African continent. Critically, in recent years there has been acknowledgement of the ability of higher education to bring about economic and democratic reforms, as evidenced by the commitment and concerted efforts made by Foundations and funding agencies to support the improvement of higher education institutions in Africa. Most important from our perspective is the support for the ’’renewal’’ of higher education institutions as they are considered to be key vehicles For development on the continent. The Commission For Africa report, published in March 2005, endorses the Association of African Universities, Association of Commonwealth Universities and Higher Education South Africa’s joint 10-year partnership programme, Renewing the African University, The partnership programme calls, among other things, For constructive engagement between states and higher education institutions, increasing North-South and South-South collaboration, internationalisation of the curriculum and partnerships between universities and the corporate sector. The Commission makes clear its conviction that higher education's contribution to building professional skills and knowledge is key to achieving Fundamental development changes. The need for centres of excellence in science, technology and engineering is highlighted as key to Future development and growth. Higher education institutions need to be the “breeding ground For the skilled individuals whom the continent needs". The report stresses the need For urgent attention to be given to the management of natural resources, of Forests and water, improving sanitation and strengthening health systems to deal with pandemics such as malaria, tuberculosis and HIV-Aids. Other important developments needed are building the human and institutional capacity for good governance and strengthening leadership in public life, civil society and business. In Focusing on the theme “lessons in diversity’ the Guide captures the richness of the various “diversities ' in the South African higher education landscape. It describes the radical transformation of higher education in South Africa over more than a decade. It identifies South Africa's research system as being “by Far the biggest in Africa” and demonstrates the important role South African higher education can play in meeting the challenges of Africa. I hope that the information provided will allow those interested in South African education to make informed choices. , 5th Edition
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  • Date Issued: 2005

Supervision : a Foucaultian exploration of institutional and interpersonal power relations between postgraduate supervisors, their students and the university domain

  • Authors: Rau, Asta
  • Date: 2005
  • Subjects: Foucault, Michel, 1926-1984 -- Methodology Foucault, Michel, 1926-1984 -- Criticism and interpretation Graduate students -- Supervision of Dissertations, Academic
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:1786 , http://hdl.handle.net/10962/d1003671
  • Description: Supervision is widely acknowledged as influencing the quality of postgraduate theses, and by association, of postgraduates. Despite this, publications on conducting research offer far less guidance on managing the supervision relationship than on the practicalities of producing a thesis. In-depth, qualitative supervision studies are few and fewer still examine power in the supervision relationship. Michel Foucault’s insights are used to explore the question: How do postgraduate supervisors and their Master’s students experience the supervision relationship and how are the dynamics of interpersonal and institutional power implicated in these relationships? Foucault argues that power relations always involve resistances; these function primarily through institutionalized discourses to produce different forms of knowledge, one form of which is identity or subjectivity. Accordingly, power relations are explored in terms of thesis-as-product, person-as-product and the impact of both on the mediation of knowledge in the educational domain. Four institutionalized discourses in the university domain are examined: · Commercial educational management discourse: targets academics through issues of quality assurance, throughput, publication, research productivity and funding. · Anarchic educational leadership discourse: integrates quantum principles with commercial demands, change management strategies and meaningful participation. · Humanistic discourse: favours a pastoral ethic and is person-centered. · Holistic discourse: cultivates ecological sensibility and values the interconnectedness of all aspects of being-in-the-world. Data collected in sixteen semi-structured interviews with three matched supervisor-student pairs selected from the humanities and education faculties of one South African university, are presented as case studies. Data analysis combines grounded theory techniques with selected aspects of Foucault’s methods. A conceptual model is devised to analyse how participants use resistance strategies to interface their autonomy and dependency with their expectations, abilities, and professional and pastoral care. The research yields rich data in which several thematic correlations in interpersonal and institutional power dynamics are grounded. These include: the significance of supervisor-student matching; links between expectations, abilities, the way participants negotiate power and the quality of professional and pastoral care they experience; the benefit of personal affinity to thesis-as-product and person-as-product; and the impact of commercial demands on participants’ power relations. Participants tend to reproduce the discourses in which they are embedded and adopt or adapt aspects of contesting discourses to this end. Potential avenues are identified for improving supervision practice and for further research.
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  • Date Issued: 2005

Supply-side ecology of the brown mussel, Perna perna: an investigation of spatial and temporal variation in, and coupling between, gamete release and larval supply

  • Authors: McQuaid, Christopher D , Lawrie, S M
  • Date: 2005
  • Language: English
  • Type: Article
  • Identifier: vital:6954 , http://hdl.handle.net/10962/d1011987
  • Description: Sampling of recruitment-associated variables of Perna perna was done approximately monthly for 14 months at intertidal locations 500 m apart, nested within sites 25 km apart. Paired with intertidal locations were nearshore locations, 600 m to sea. Sampling assessed spawning, densities of larvae in the water column and densities of late plantigrades and juveniles on the shore. Major events in each variable were synchronous over larger scales (10s of kilometres) while subsidiary events were synchronised at smaller scales, varying within sites (100s of metres) or even within locations (metres). This suggests that the processes driving major events operated over large scales while processes operating at much more local scales drove less intense, more localised events. A major spawning event occurred at all locations in May–June 1998. Weaker spawning events occurred at different times in different locations. Larvae were found on 80% of sampling occasions, densities peaking in January–March 1998 and 1999 at all locations. Plantigrades and juveniles showed less clear patterns, with considerable residual variation. There was no sign of strong coupling among variables with few significant direct or cross correlations. The major sources of variability shifted from time to space as one progressed from spawning, to plantigrade density to juvenile density. For spawning, time was the most important source (58%) of heterogeneity and space accounted for little (8%) of the total variance. For larvae and late plantigrades, time was still the most important source of variability (41% and 33%, respectively), but space was a much more substantial component. For juveniles, small-scale (residual) spatial variability dominated total variability (75%). This strongly suggests the importance of hydrography and its effects on variation in delivery of larvae to the intertidal from offshore. These findings also indicate greater spatial heterogeneity as recruits age, reflecting small-scale variations in larval delivery and the increasing importance of post-settlement mortality.
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  • Date Issued: 2005

Surface electrochemistry of iron phthalocyanine axially ligated to 4-mercaptopyridine self-assembled monolayers at gold electrode

  • Authors: Ozoemena, Kenneth I , Nyokong, Tebello
  • Date: 2005
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/289282 , vital:56615 , xlink:href="https://doi.org/10.1016/j.jelechem.2005.02.018"
  • Description: Surface electrochemical behaviour of a self-immobilised iron phthalocyanine (FePc) ultrathin film, via axial ligation reaction, onto a preformed 4-mercaptopyridine self-assembled monolayer on gold electrode has been described. Electrochemical evidence for the sensor clearly suggested surface-confined, flat “umbrella”-oriented and densely-packed monolayer film structure. The proposed electrochemical sensor exhibited good catalytic activity towards the oxidation of thiocyanate in pH 4.0 medium over a linear range of three decades of concentration (ca. 10−6–10−3 mol dm−3) with a detection limit in the order of ∼10−7 mol dm−3. The sensor exhibited useful potential for the analysis of thiocyanate in human urine and saliva samples. The advantageous properties of this type of electrode as a sensor for thiocyanate lie in its ease of fabrication, excellent catalytic activity, stability, sensitivity and simplicity.
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  • Date Issued: 2005

Synthesis and electrocatalytic properties of polymerizable metallophthalocyanines

  • Authors: Obirai, Joseph Chinye
  • Date: 2005
  • Subjects: Phthalocyanines Electrochemistry
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:4447 , http://hdl.handle.net/10962/d1007733
  • Description: The syntheses, spectral and electrochemical characterization of new family electropolymerizable pyrrole, thiophene and mercaptopyrimidin substituted metallophthalocyanine (MPc) complexes are described. Tetraamino substituted chromium and manganese phthalocyanine complexes were also synthesized and characterized. The spectral and electrochemical results are comparable to literature reports. The complexes formed stable films when deposited on electrode surfaces. The MPc films were formed by electropolymerization, drop-dry method and self-assembling. Nickel hydroxide-like electrodes were formed by electrotransformation of nickel-tetra-4- (pyrrol-1-yl)phenoxy phthalocyanine polymer films to the corresponding PcNi-O-NiPc modified electrodes in alkaline solution. The thiophene, mercaptopyrimidine functionalized MPcs and amino group containing complexes formed good self-assembled monolayers (SAMs) on gold electrode. The electrode modification processes were reproducible. The conductivities of the electrode were dependent on the surface concentrations of the complexes as a function of electropolymerization scan numbers. The electrodes showed good catalytic responses toward L-cysteine, nitrite, nitric oxide (NO), glycine, phenol and its derivative and oxygen. The results also suggest that the presence of thio groups on the ring substituents lowers the oxidation potential of Lcysteine more compared to literature values. The stability of the amperometric responses toward the various analytes is used to diagnose the applicability of the materials for electroanalytical purposes. The limits of detection for L-cysteine, nitrite, NO and glycine were in the range of ~10⁻⁷ to 10⁻⁵ mol dm⁻³.
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  • Date Issued: 2005

Synthesis and photophysical properties of a covalently linked porphyrin-phthalocyanine conjugate

  • Authors: Zhao, Zhixin , Ogunsipe, Abimbola O , Maree, M David , Nyokong, Tebello
  • Date: 2005
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/300358 , vital:57922 , xlink:href="https://doi.org/10.1142/S1088424605000253"
  • Description: The synthesis of a phthalocyanine-porphyrin heteropentamer (zinc(II) tetra(5-phenoxy-10,15,20-triphenylporphyrin)) zinc(II) phthalocyanine, (ZnPc-(ZnTPP)4), containing four units of zinc tetraphenylporphyrin linked to a central zinc phthalocyanine macrocycle via an ether linkage is reported. The photophysical parameters of the pentamer are reported in toluene and dimethyl sulfoxide (DMSO). The observed differences in the fluorescence behavior of the pentamer in the two solvents is explained in terms of emission from different states; charge transfer state in DMSO and locally excited state in toluene. The rate constants for fluorescence, intersystem crossing, internal conversion, and of charge and energy transfer are reported for the pentamer. Quantum yields for fluorescence, internal conversion, triplet state and of charge and energy transfer are also reported for the pentamer, ZnPc-(ZnTPP)4 and the mixture of ZnPc and ZnTPP. The latter two parameters are higher in the pentamer compared to a mixture containing ZnPc and ZnTPP.
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  • Date Issued: 2005

Synthesis, electrochemical and electrocatalytic behaviour of thiophene-appended cobalt, manganese and zinc phthalocyanine complexes

  • Authors: Obirai, Joseph , Nyokong, Tebello
  • Date: 2005
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/286103 , vital:56238 , xlink:href="https://doi.org/10.1016/j.electacta.2005.03.024"
  • Description: This work reports on the syntheses of new thiophene tetra substituted cobalt, manganese and zinc phthalocyanine (CoTETPc, (Cl)MnTETPc and ZnTETPc) complexes. The redox processes due to the thiophene substituent on the ring of the metallophthalocyanines (MPcs) were observed, in addition to Pc ring and metal (for Co and Mn complexes) based redox activity. The electrocatalytic activity of the CoTETPc complex adsorbed on glassy carbon electrode (GCE) by drop/dry-thermal annealing was investigated using L-cysteine. The modified electrode was stable to repetitive use without any signs of deactivation by oxidation products and was used to determine L-cysteine at concentrations between 0.0015 and 1 mM in pH 4 aqueous conditions.
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  • Date Issued: 2005

Synthesis, photochemical and photophysical properties of phthalocyanine derivatives

  • Authors: Maqanda, Weziwe Theorine
  • Date: 2005 , 2013-06-18
  • Subjects: Photochemotherapy , Phthalocyanines , Zinc , Magnesium
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4436 , http://hdl.handle.net/10962/d1007472 , Photochemotherapy , Phthalocyanines , Zinc , Magnesium
  • Description: Substituted zinc and magnesium phthalocyanine and porphyrazine derivatives were synthesized according to the reported procedures. The magnesium and zinc phthalocyanine and porphyrazine derivatives were synthesized by ring enlargement of subphthalocyanine and statistical condensation of the two phthalonitrile derivatives. Characterization of the complexes involved the use of infrared spectroscopy, nuclear magnetic resonance spectroscopy, ultraviolet and visible spectroscopy, and Maldi-TOF spectroscopy (for selected compounds) and elemental analysis. Photochemical and photophysical properties of the complexes in non-aqueous solution was then investigated. Photobleaching quantum yields are in order of 10⁻⁵ indicating their relative photostability. Complexes containing more electron-donating substituents were more easily oxidized. For complexes 66 and 69 (as these complexes have the same number of substituents but differ in the metal center) photobleaching quantum yield for the ZincPc complex 69 was slightly less than that of the MgPc complex 66. Singlet oxygen quantum yields of the various complexes in DMSO using diphenylisobenzofuran (DPBF) as a quencher in organic solvents were determined. Singlet oxygen quantum yields of the complexes range from 0.23 to 0.67. High values of Φ[subscript]Δ ZnPc complexes was observed compared to the corresponding MgPc, complexes. This was evidenced by complexes 66 and 69 with Φ[subscript]Δ values of Φ[subscript]Δ = 0.26 and 0.40, respectively. Varying number of phenoxy substituents, complex 71 gave significantly large value of Φ[subscript]Δ compared to 70 (that is, the presence of more electron-donating substituted group, gave higher singlet oxygen quantum yields (0 .67 and 0.25 for 71 and 70 repectively). The triplet quantum yields and triplet lifetimes were determined by laser flash photolysis for selected compounds. The triplet quantum yields increase as the number of substituents increases e.g 68 > 67 > 66. Comparing porphyrazine complexes (63, 64 and 65), 63 with benzene attached to the ring, has higher triplet state lifetime (420 μs) compared to 64 and 65 containing long alkyl chain and tertbutyl substituents, 350 and 360 μs,respectively). The observed Φ[subscript]f values for 68 and 63 were quiet suprising, since low values are observed compared to the rest of the complexes (e.g 0.03 and 0.02 respectively). Although these values seem so low, they are sufficient for fluorescence imaging applications. The Φ[subscript]f values for the complexes under study are within the range reported for complexes currently used for PDT. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
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  • Date Issued: 2005

Synthesis, photophysicochemical studies of adjacently tetrasubstituted binaphthalo-phthalocyanines

  • Authors: Seotsanyana-Mokhosi, Itumeleng , Chen, Ji-Yao , Nyokong, Tebello
  • Date: 2005
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/289294 , vital:56616 , xlink:href="https://doi.org/10.1142/S108842460500040X"
  • Description: Adjacent binaphthalo-phthalocyanines tetra-substituted with phenoxy (4a), 4-carboxyphenoxy (4b) and 4-t-butylphenoxy (4c) groups, as well as the di-substituted 4-carboxyphenoxy (5b) have been synthesized and characterized. The photophysical and photochemical behavior of 4a-c, were compared with those of the corresponding di-substituted derivatives, (5a-c). The secondary substituents on the phenoxy ring have an influence on the aggregation of the molecules and hence on their photophysical properties. All of the complexes exhibit a relatively good conversion of energy from the triplet-excited state to the singlet oxygen. The less aggregated molecule (4c), has the highest singlet oxygen quantum yield. For all the molecules, fluorescence yields are low and they all have relatively shorter triplet lifetimes compared with the unsubstituted zinc phthalocyanine. Increasing the number of ring substituents on these rigid MPc complexes (from complexes 5 to 4) showed a general increase in the triplet state lifetimes and singlet oxygen quantum yields, and a decrease in stability.
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  • Date Issued: 2005

Talk radio and public debate : a case study of three Ugandan radio stations

  • Authors: Ogoso, Erich Opolot
  • Date: 2005
  • Subjects: Radio stations -- Uganda , Radio broadcasting -- Social aspects -- Uganda , Radio broadcasting -- Political aspects -- Uganda , Radio talk shows -- Uganda , Interviewing on radio -- Uganda
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:3514 , http://hdl.handle.net/10962/d1007723 , Radio stations -- Uganda , Radio broadcasting -- Social aspects -- Uganda , Radio broadcasting -- Political aspects -- Uganda , Radio talk shows -- Uganda , Interviewing on radio -- Uganda
  • Description: This study is a comparative examination of approaches to talk radio as a genre on three Ugandan radio stations. The aim is to draw conclusions, from observations made about these stations, about the potential of talk radio to encourage public debate around social issues and improve democratic participation despite pertinent challenges in Uganda. The study first outlines a theoretical framework, which is informed by Habermas's theory of the media as a 'public sphere'. This framework is applied to an exploration of traditions of talk radio that have emerged globally in order to assess the potential of these traditions to play a role in contributing to the establishment of such a 'public sphere'. The study then goes on to discuss the historical development of radio in Uganda and the establishment of the current broadcast landscape. The focus is on the way in which this history has been defined by a struggle around public expression, in which government has repeatedly sought ways to control media as a vehicle for public expression. It is proposed that Ugandan talk radio has the potential to play an important role in ensuring broad participation in public expression. It is against this background that the study then describes and analyses the development of the talk genre at three Ugandan radio stations (each one an example of, respectively, a commercial, community and public service station). It is explained that staff on all three stations emphasise the importance of talk radio in encouraging participation, by their audiences, in the public debate of social and political issues. It is argued that, because of limitations that exist within these stations, none of the talk show teams fully realize the potential of the genre for participation in such debate. The picture that emerges is one of unequal access, with those sections of radio audiences in positions of privilege being further empowered, while those on the margins remain excluded from public discussion. The study finally recommends ways to improve public participation on Ugandan talk radio, noting the need to review government support, the problems of organizational culture within the stations, the need for more guidelines on practical arrangements around talk show production and the question of contradictions that exist at policy level.
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  • Date Issued: 2005

Tanzaniops, replacement name for certain African Baetidae (Ephemeroptera)

  • Authors: McCafferty, W P , Barber-James, Helen M
  • Date: 2005
  • Language: English
  • Type: Article
  • Identifier: vital:7009 , http://hdl.handle.net/10962/d1008387
  • Description: The name Tanzaniella, proposed for an African baetid mayfly by Gillies (1991) was preoccupied. The name Tanzaniops is provided as a replacement for this homonym.
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  • Date Issued: 2005

Teacher adaptation of a curriculum during implementation

  • Authors: Childs, Margaret Mary
  • Date: 2005
  • Subjects: Curriculum change -- South Africa , Educational change -- South Africa
  • Language: English
  • Type: Thesis , Masters , MPhil
  • Identifier: vital:9486 , http://hdl.handle.net/10948/377 , Curriculum change -- South Africa , Educational change -- South Africa
  • Description: The purpose of this study is to investigate to what extent foundation phase teachers adapt Curriculum 2005. The study was guided by two research questions: (1) What are the critical components of Curriculum 2005 (foundation phase)? (2) What are the adaptations that teachers have made in teaching this curriculum? The specific focus of this study is foundation phase teachers’ initial implementation of the revised version of Curriculum 2005, the Revised National Curriculum Statement (RNCS). An Innovation Configuration Checklist was developed identifying the critical components of the RNCS and the variations of each. Using the checklist, foundation phase teachers were surveyed to establish the adaptations being made during implementation. The findings of this study indicate that there is less active learning and more teacher directed activity than is required by the RNCS. Assessment appears to be a problem area. Most teachers understand what is expected of them in terms of assessment and attempt to put it into practice. Assessment has however, proved to be burdensome and time consuming. Teachers’ planning demonstrates a sound understanding of the procedures to be followed. Teachers do however, need support in terms of deeper pedagogical content knowledge. Although teachers comply with the technical aspects of curriculum development they neglect the emancipatory aspects of the RNCS. The situation in foundation phase classrooms might be described as one where much change is taking place, but little transformation is happening at present. Teachers are nevertheless, reflecting on how to improve their teaching and continue to explore ways to adapt and improve the RNCS.
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  • Date Issued: 2005

Teacher receptivity of an integrated curriculum with special reference to the foundation phase of curriculum 2005

  • Authors: Nthulanyane, Malefa Regina
  • Date: 2005
  • Subjects: Interdisciplinary approach in education -- South Africa , Primary school teachers -- South Africa -- Eastern Cape , Education, Primary -- South Africa -- Curricula
  • Language: English
  • Type: Thesis , Masters , MPhil
  • Identifier: vital:11011 , http://hdl.handle.net/10948/378 , Interdisciplinary approach in education -- South Africa , Primary school teachers -- South Africa -- Eastern Cape , Education, Primary -- South Africa -- Curricula
  • Description: The purpose of the study was to investigate teacher receptivity of a new curriculum, in particular, the new integrated curriculum of South Africa. As the New Revised national curriculum Statement is starting to be operational this year, Curriculum 2005 was used as a model of an integrated curriculum in this study. The study focused on the following sub-problems: the meaning of an integrated curriculum; teacher receptivity of an integrated curriculum; and the extent to which teachers are receptive of the new integrated foundation phase curriculum. The review of relevant literature provided a conceptual framework for the study. Six dimensions of a curriculum that were regarded as critical in classroom practice for practicing teachers were identified and used to describe an integrated curriculum. These were: platform, learning outcomes, content, instructional materials, teaching and learning strategies and assessment. The conceptual framework for teacher receptivity was also identified by means of review of relevant literature. Teacher receptivity was conceptualised as comprising of attitudes and behavioral intentions. The empirical part of the study was undertaken to determine the attitudes of teachers towards an integrated foundation phase curriculum and the extent to which foundation phase teachers were receptive of the new curriculum. The sample for the empirical part of the study included 63 foundation phase teachers randomly selected from 21 schools in Herschel District. The schools were randomly selected from 3 zones which had been randomly selected from 7 zones that make up Hershel Educational District in the Eastern Cape, South Africa. Empirical data on teachers’ attitudes towards an integrated curriculum indicated that the majority of teachers were viewed the curriculum in an extremely positive light/somewhat positive light. There were responses which indicated that some teachers regarded the curriculum as complicated, restrictive, and idealistic. This situation is highlighted in their responses to the semantic differential on the attitude objects of the curriculum. Data on teacher receptivity indicated positive responses but vi there were some area of concern such as, for example, support from the district manager, school and the community. Data indicated that teachers were not so positive abut learning outcomes and assessment as a basis of teaching an integrated curriculum. Based on the empirical part of the study, conclusions and recommendations were made.
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  • Date Issued: 2005

Tertiary treatment in integrated algal ponding systems

  • Authors: Wells, Charles Digby
  • Date: 2005
  • Subjects: Sewage -- Purification -- Anaerobic treatment , Water -- Purification -- Biological treatment
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4068 , http://hdl.handle.net/10962/d1006162 , Sewage -- Purification -- Anaerobic treatment , Water -- Purification -- Biological treatment
  • Description: Inadequate sanitation is one of the leading causes of water pollution and consequently illness in many underdeveloped countries, including South Africa and, specifically, the Eastern Cape Province, where cholera has become endemic. As modern wastewater treatment processes are often energy intensive and expensive, they are not suitable for use in these areas. There is thus a need to develop more sustainable wastewater treatment technologies for application in smaller communities. The integrated algal ponding system (IAPS) was identified as a possible solution to this wastewater management problem and was investigated for adaptation to local conditions, at the Rhodes University Environmental Experimental Field Station in Grahamstown, South Africa. The system was monitored over a period of nine years, with various configuration adjustments of the high rate algal pond (HRAP) unit operation investigated. Under standard operating conditions, the system was able to achieve levels of nutrient and organic removal comparable with conventional wastewater treatment works. The mean nitrate level achieved in the effluent was below the 15mg.l-1 South African discharge standard, however, nitrate removal in the IAPS was found to be inconsistent. Although the system was unable to sustain chemical oxygen demand (COD) removal to below the 75mg.l-1 South African discharge standard, a removal rate of 87% was recorded, with the residual COD remaining in the form of algal biomass. Previous studies in the Eastern Cape Province have shown that few small wastewater treatment works produce effluent that meets the microbial count specification. Therefore, in addition to the collation of IAPS data from the entire nine year monitoring period, this study also investigated the use of the HRAP as an independent unit operation for disinfection of effluent from small sewage plants. It was demonstrated that the independent high rate algal pond (IHRAP) as a free standing unit operation could consistently produce water with Escherichia coli counts of 0cfu.100ml-1. The observed effect was related to a number of possible conditions prevailing in the system, including elevated pH, sunlight and dissolved oxygen. It was also found that the IHRAP greatly enhanced the nutrient removal capabilities of the conventional IAPS, making it possible to reliably and consistently maintain phosphate and ammonium levels in the final effluent to below 5mg.l-1 and 2mg.l-1 respectively (South African discharge standards are 10mg.l-1 and 3mg.l-1 in each case). The quality of the final effluent produced by the optimisation of the IAPS would allow it to be used for irrigation, thereby providing an alternative water source in water stressed areas. The system also proved to be exceptionally robust and data collected during periods of intensive and low management regimes were broadly comparable. Results of the 9 year study have demonstrated reliable performance of the IAPS and its use an appropriate, sustainable wastewater treatment option for small communities.
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  • Date Issued: 2005

The anatomy and distribution of the cyperaceae in the Eastern Cape region of South Africa

  • Authors: Sonnenberg, Bernd Jürgen
  • Date: 2005
  • Subjects: Cyperaceae Cyperaceae -- Anatomy Cyperaceae -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:4228 , http://hdl.handle.net/10962/d1003797
  • Description: The principal objective of this investigation, was to collect the family Cyperaceae and to study their leaf, bract and culm anatomy. The second was to examine the collection for unique structures or forms, whilst a third was to classify the Cyperaceae according to their photosynthetic structures and types. Distribution of the Cyperaceae within the broad region defined as the Eastern Cape would be influenced by rainfall pattern. It was expected that C₃ species would predominate in more mesic environments and habitats, whilst the C₄ species would be found in drier less favourable habitats. Collection within the region (November 1993 to late January 1997), yielded 106 species, totalling some 600 specimens. Both sub-families of the Cyperaceae (Caricoideae and Cyperoideae), eight tribes (Abildgaardieae, Cariceae, Cypereae, Hypotvtreae, Rhynchosporeae, Shoeneae, Sirpeae and Slerieae) and twenty five genera were found to be present. Sixty percent of the species were C₃ and forty percent were C₄. Sixteen new species, which had not been collected within the boundaries of the region previously were also found. Over 43 percent of the species collected had unique anatomical characteristics that appeared to be influenced by habitat and or climate influenced. These are the characters influenced by hydromorphic, mesomorphic and xeromorphic environments. These anatomical characters: Thickness of leaves and bracts; thickness of the adaxial and abaxial epidermis of the leaves and bracts; flush, sunken and raised stomata; presence or absence of bulliform cells; presence and distribution of sclerenchymatous structures; presence or absence of a hypodermis; presence or absence of cavities in the leaves, bracts and culms; mesophyll or ground tissue structure, and the presence or absence of secretary structures. A few noteworthy anatomical characters that are influenced by climate are present in Cladium mariscus subsp. jamaicense (Schoeneae), the Cariceae, the Cypereae and the Sclerieae. Within Cladium mariscus subsp. jamaicense the pseudo-dorsiventral leaves and bracts, as well as the large lamina cavities, containing trans-lamina girders are unique. Papillate epidermal cells are limited to the tribe Cariceae. In the Cypereae many of the species lack bulliform cells and hypodermal layers. In Pycreus cooperi (Cypereae) the vascular bundles of the leaves and bracts, appear to be stacked in rows, that are inter-spaced with lamina cavities. In the Sclerieae the mesophyll structure is specific to the species level. Unique anatomical characteristics were also present in the leaves, bracts and culms of the genus Carpha. In this genus distinctive lateral vascular bundles were present abutting the large bundles and/or midrib bundle. The most distinctive anatomical characteristics that could be used to separate the members of the Cyperaceae were the structures and associated structures related to the photosynthetic pathway. The Eastern Cape Cyperaceae could be divided into three distinct groups based on photosynthetic structure, namely one C₃, a C₄ and a potential C₃-C₄ intermediate group. The C₃ group was found to have non-radiate mesophyll and an outer parenchymatous sheath with small chloroplasts (Cariceae, Cyperaceae [in part], Hypolytreae (Chrysithrix capensis], Rhynchosporeae [R. brownii], Schoeneae, Scirpeae and Sclerieae). The C₄ group has radiate mesophyll and an inner parenchymatous sheath with enlarged chloroplasts (Kranz or PCR sheath). The C₄ species are present in tribes Abildgaardieae, Cypereae (in part) and Rhynchosporeae (R. barrosiana). In the Eastern Cape, a few species with C₃ anatomy have anatomical characteristics that are similar to the species with C₄ anatomy (Cyathocoma hexandra [bracts], Cyperus tennellus var. tennellus [leaves and bracts], Ficinia bulbosa [leaves], F. dura [leaves and bracts], F. lateralis coastal [leaves and bracts], F. oligantha [bracts], F. pingiour [bracts], F. stolonifera [leaves and bracts], F. tribracteata [leaves and bracts], F. zeyheri [leaves and bracts], Isolepis cernua [leaves and bracts], I. costata var. macra [bracts], Schoenus nigricans [leaves], Scirpus nodosus [bracts] and Tetraria cuspidata [leaves and bracts)). The vascular bundles within this intermediate group, fall within the Hattersleyand Watson (1975) minimal cell lateral count and maximal cell distal count criteria for C₄ grass species. However, no biochemical data exists to see whether they are C₃-C₄ intermediates or whether the Hattersley and Watson (1975) C₄ criteria for grasses applies to smaller, or scutiform Cyperaceae or not. Based on the results presented here, five distinct structural forms/types were found to be present in the C₃, C₄ and C₃-C₄ intermediate groups. The C₃ and the potential C₃-C₄ intermediate species may be divided into two types, based on the number of vascular sheaths present. In the first or A-type, vascular bundles are surrounded by two sheaths and in the more dominant B-type, by three. The A-type was found in the Cypereae (Cyperus denudatus and C. textilis) and most of the Scirpeae. B-type anatomy occurred in the Cariceae, Cypereae (c. difformis, C. pulcher, C. sphaerospermus, C. tennellus var. tennellus and P. mundii), Hypolytreae, Rhynchosporeae (R. brownii), Schoeneae, Scirpeae (Bolboschoenus maritimus, Ficinia cinnamomea, F. fascicularis, F. lateralis both, F. pingiour, the genus Fuirena, I. diabolica, I. fluitans, I. prolifera and Schoenoplectus paludicola) and Sclerieae tribes. Based on the vascular sheath structure, the C₄ species could be divided into three groups, namely bulbostyloid, chlorocyperoid and fimbristyloid, where the bulbostyloid structure occurred in Bulbostylis schoenoides. Cyperus (in part), Kyllinga, Mariscus and Pycreus (except P. mundii) had a chlorocyperoid structure. Genera with fimbristyloid structure were recorded in the genera Abildgaardia, Bulbostylis and Fimbristylis. The bulbostyloid type represents a potential a fifth C₄ anatomical type within the C₄ Cyperaceae. As a result of this observation, it is possible that the C₄ syndrome may have evolved five times in the Cyperaceae and not four as previously suggested by Bruhl and Perry (1995) and by Soros and Dengler (2001). The C₃ Cyperaceae species within the Eastern Cape are more dominant in higher elevation habitats the C₄ species, similar to the C₃ grasses. The only C₄ species that occur at high elevations are those with three sheaths. The C₃ and C₄ species within the region occur in similar low rainfall habitat ranges, where the C₄'s are more dominant in xeric habitats on drier soils than the C₃ species, similar to the grasses. Where more C₃ species occur in higher rainfall habitats than the C₄ species. With the exception of the Afromontane Bulbostylis schoenoides and R. barrosiana, the C₄ species similar to the grasses are dominant in high light and temperature habitats with low rainfall, unlike the C₄ Cyperaceae of Japan and America. Only five species occur in the desert like conditions of the Karoo-Namib biome (Cyperus laevigatus, C. rupestris var. rupestris, I. cernua, M. capensis and M. uitenhagensis), which have less than 250mm of rainfall per annum. Only three species are habitat-specific or may be endemic to a specific area within the Eastern Cape, namely A. capensis, Chrysithrix capensis and R. barrosiana. A. capensis in marshes on the Amatole mountains near Alice and Hogsback. C. capensis to the Tstsikamma mountains of the Wite Els Bosch forests. R. barrosiana to the marshlands of the Cape Morgan coastal Nature reserve at Kei Mouth. The anatomical types of the C₃ and more especially C₄ Cyperaceae are not specifically found in a particular rainfall regime or habitat type, which is contrary to the thesis hypothesis. However, the C₃ species are mostly correlated with hydrophytic to mesic habitats, with the exception of Ficinia and the two sheathed species. Ficinia is dominant in mesic grasslands and halophytic habitats. The two sheathed C₃ species are mostly present in halophytic habitats. The C₄ species are also more dominant in mesic to xerophytic grasslands, as expected in the hypothesis. Where only a few species occur in habitats correlated with increasing rainfall and temperature similar to the C₄ Cyperaceae of Japan and America. It may thus be that the development and evolution of the different C₄ anatomical forms (or phylogenetic forms) within the Cyperaceae may have enabled these species to establish themselves in habitats that were alien to their origins. It may be that the ability to regulate photoassimilate and water transport within the Cyperaceae enables their success in a dynamic and unpredictable climate, such as the Eastern Cape. Many of the anatomical characteristics reported in this thesis and its appendices are unique to the tribes, genera and/or species of the Eastern Cape Cyperaceae and thus may be valuable to future taxonomic classifications of the family. The research presented here should provide a good working platform for future, more detailed research on this often forgotten component of the vegetation.
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  • Date Issued: 2005
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