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Street tree composition, distribution and urban residents’ perceptions within and between Eastern Cape towns

  • Authors: Gwedla, Nanamhla
  • Date: 2016
  • Subjects: Urbanization -- South Africa -- Eastern Cape , Urban ecology (Sociology) -- South Africa -- Eastern Cape , Tree planting -- South Africa -- Eastern Cape , Trees in cities -- Environmental aspects -- South Africa -- Eastern Cape , Urban forestry -- Law and legislation -- South Africa -- Eastern Cape , Low-income housing -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/4702 , vital:20714
  • Description: Promoting urban sustainability is vital in the face of rapid human and urban population growth. A core tenet of urban sustainability, urban forestry, is poised to “go global” with the intent of mitigating the negative environmental and social effects of urbanisation through green infrastructure, spaces and trees. Amongst these, the planting of street trees has become a major strategy. The public functions of street trees as demonstrated through the provision of ecosystem services are highly dependent on the structure, composition and diversity of tree species within the urban forest. The bulk of available literature on the composition, diversity and perceptions of residents regarding street trees has largely focused on the developed world, while the few in the developing world have been conducted at only one or two sites. The aim of this study was to investigate the composition, diversity and density of urban street trees in relation to the perceptions of local residents and horticulturists, across a range of ecological and social contexts. To do this, the species composition, diversity and dominance of street trees planted in 10 randomly selected Eastern Cape towns was assessed. Within each town ten replicate 200 m transects were located in three different suburbs. Perceptions and appreciation of street trees were assessed by 1 200 household questionnaires, as well as key informant interviews with personnel responsible for street tree planting and maintenance. Sixty-nine out of 300 sampled transects had street trees, with 888 trees enumerated, spanning ninety-seven species. Alien tree species accounted for 71 % of all the enumerated trees while indigenous trees species accounted for 12 %. The non-former homeland towns had a significantly higher (5.8±1.6 trees) mean street tree density per transect than the former homeland towns (0.6±03). There were no significant relationships between street tree density or richness to mean annual rainfall or the background biome in which the town was situated. However, density strongly was related to size of the town. RDP and township suburbs had fewer street trees and low species richness relative to the affluent suburbs. In selecting street trees, root system of the prospective tree, the eventual size or shape of the species, whether an alien or indigenous species, and the species’ adaptability to the climate of the respective town are considered before planting. The biggest identified threats to street trees were the deliberate vandalism of trees by people and animals, and lack of education and awareness regarding the importance of street trees among urban residents and municipal officials. More than half of the respondents prefer that trees be planted both on the street and in their yards while a few do not want trees at all. The majority of respondents with this preference do so because they want shade and abundant fruit, and to have beautiful yards and streets. Those who do not want trees at all do so because they just do not like trees, there is no space for trees, or they fear that criminals hide behind trees. The presence of trees in peoples’ yards correlated with a positive preference for trees in the street. The majority of respondents were neither satisfied with the general appearance of their street nor with the number of trees on their street. Residents from the RDP suburbs were the least satisfied with both the appearance and number of trees on their streets, while those from the affluent suburbs were the most satisfied. Street trees were seen as greatly important to have by the majority of people. The more educated people were more appreciative of the importance of street trees. Local municipalities were identified by the majority of respondents as the stakeholders responsible for the planting and maintenance of street trees, although a considerable proportion of respondents reported a willingness to volunteer to help plant and maintain trees on their streets. Municipalities were seen as doing very little to provide and maintain trees in the various suburbs by the majority of respondents. The majority of respondents also reported that they had never been consulted about tree planting activities in their suburbs before, and would like to have been consulted.
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  • Date Issued: 2016

Stripe & dusk: a weekend odyssey

  • Authors: Whitehorn, Daniel J
  • Date: 2016
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:6018 , http://hdl.handle.net/10962/d1021242
  • Description: I love to take in and create playful fantasy, tales set in wild and fantastic worlds peopled by wild and fantastic characters - dragons and dinosaurs, knights and robots, stars and penguins. My novella is the story of a quest set in a colourful and wondrous fantasy universe. Along the journey's tumultuous trajectory fantasy tropes and protocols are encountered, subverted, teased at, appropriated, and renovated, in order to create something both original and familiar all at once. I am happy to acknowledge and salute the influences of Terry Pratchett, Douglas Adams, Walter Moers and Manuela Draeger.
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  • Date Issued: 2016

Stromatolite microbial communities as a source of new bioactive secondary metabolites

  • Authors: Flatt, P M , Damarjanan, C , Isamonger, E , Kalinski, Jarmo-Charles J , Dorrington, Rosemary A , McPhail, Kerry L
  • Date: 2016
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/65871 , vital:28851 , https://doi.org/10.1055/s-0036-1596638
  • Description: publisher version , Stromatolites represent some of the earliest microbial communities on Earth. They are formed by accretion and precipitation of layered calcium carbonate structures that result from the metabolic activity of complex microbial communities and the geochemical conditions of their environment. Modern stromatolite communities include aerobic heterotrophs, sulphide-oxidizing bacteria, sulphate-reducing bacteria, fermentative bacteria and cyanobacteria. Phylogenetic analyses revealed the presence of new and known cyanobacterial taxa related to known producers of biologically active secondary metabolites in tufa stromatolites along the South African southeast coast [1]. Prompted us to investigate their potential for producing novel bioactive secondary metabolites. A series of three tide pools provided the opportunity to collect stromatolites along a vertical transect from pool A (highest elevation, low nitrogen input, fresh water), pool B (within high tide zone, brackish water) and pool C (within tidal zone). The microbial community in pool A is particularly distinct. Chemical extracts of stromatolites from different pools have been profiled by LC-MS/MS and the data subjected to molecular spectral networking using the GnPS platform [2] in order to establish the diversity and biological potential of the microbial metabolome that is being expressed within each of these microhabitats. Correlation of the phylogenetic and secondary metabolomic data is expected to guide the isolation of new natural products with biomedical relevance.
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  • Date Issued: 2016

Structural bioinformatics studies and tool development related to drug discovery

  • Authors: Hatherley, Rowan
  • Date: 2016
  • Subjects: Structural bioinformatics , Drug development , Natural products -- Databases , Natural products -- Biotechnology , Sequence alignment (Bioinformatics) , Malaria -- Chemotherapy , Heat shock proteins , Plasmodium falciparum
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:4164 , http://hdl.handle.net/10962/d1020021
  • Description: This thesis is divided into two distinct sections which can be combined under the broad umbrella of structural bioinformatics studies related to drug discovery. The first section involves the establishment of an online South African natural products database. Natural products (NPs) are chemical entities synthesised in nature and are unrivalled in their structural complexity, chemical diversity, and biological specificity, which has long made them crucial to the drug discovery process. South Africa is rich in both plant and marine biodiversity and a great deal of research has gone into isolating compounds from organisms found in this country. However, there is no official database containing this information, making it difficult to access for research purposes. This information was extracted manually from literature to create a database of South African natural products. In order to make the information accessible to the general research community, a website, named “SANCDB”, was built to enable compounds to be quickly and easily searched for and downloaded in a number of different chemical formats. The content of the database was assessed and compared to other established natural product databases. Currently, SANCDB is the only database of natural products in Africa with an online interface. The second section of the thesis was aimed at performing structural characterisation of proteins with the potential to be targeted for antimalarial drug therapy. This looked specifically at 1) The interactions between an exported heat shock protein (Hsp) from Plasmodium falciparum (P. falciparum), PfHsp70-x and various host and exported parasite J proteins, as well as 2) The interface between PfHsp90 and the heat shock organising protein (PfHop). The PfHsp70-x:J protein study provided additional insight into how these two proteins potentially interact. Analysis of the PfHsp90:PfHop also provided a structural insight into the interaction interface between these two proteins and identified residues that could be targeted due to their contribution to the stability of the Hsp90:Hop binding complex and differences between parasite and human proteins. These studies inspired the development of a homology modelling tool, which can be used to assist researchers with homology modelling, while providing them with step-by-step control over the entire process. This thesis presents the establishment of a South African NP database and the development of a homology modelling tool, inspired by protein structural studies. When combined, these two applications have the potential to contribute greatly towards in silico drug discovery research.
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  • Date Issued: 2016

Structure based docking and molecular dynamic studies of plasmodial cysteine proteases against a South African natural compound and its analogs:

  • Authors: Musyoka, Thommas M , Kanzi, Aquillah M , Lobb, Kevin A , Tastan Bishop, Özlem
  • Date: 2016
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/148027 , vital:38703 , DOI: 10.1038/srep23690
  • Description: Identification of potential drug targets as well as development of novel antimalarial chemotherapies with unique mode of actions due to drug resistance by Plasmodium parasites are inevitable. Falcipains (falcipain-2 and falcipain-3) of Plasmodium falciparum, which catalyse the haemoglobin degradation process, are validated drug targets. Previous attempts to develop peptide based drugs against these enzymes have been futile due to the poor pharmacological profiles and susceptibility to degradation by host enzymes. This study aimed to identify potential non-peptide inhibitors against falcipains and their homologs from other Plasmodium species.
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  • Date Issued: 2016

Student tasting traditional beer

  • Authors: Student
  • Date: 2016
  • Subjects: Keiskammahoek (South Africa)
  • Type: Image
  • Identifier: http://hdl.handle.net/10962/219839 , vital:48562 , KHP-193
  • Description: Photograph of student tasting traditional beer. , Use of this resource is governed by the terms and conditions of the Creative Commons "Attribution-NonCommercial-ShareAlike" License (http://creativecommons.org/licenses/by-nc-sa/2.0/)
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  • Date Issued: 2016

Students sitting outside with men

  • Authors: Men , Students
  • Date: 2016
  • Subjects: Keiskammahoek (South Africa)
  • Type: Image
  • Identifier: http://hdl.handle.net/10962/219774 , vital:48556 , KHP-186
  • Description: Photograph of Students sitting outside with the men. , Use of this resource is governed by the terms and conditions of the Creative Commons "Attribution-NonCommercial-ShareAlike" License (http://creativecommons.org/licenses/by-nc-sa/2.0/)
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  • Date Issued: 2016

Students’ reception of peer assessment of group-work contributions: problematics in terms of race and gender emerging from a South African case study

  • Authors: Thondhlana, Gladman , Belluigi, Dina Z
  • Date: 2016
  • Language: English
  • Type: article , text
  • Identifier: http://hdl.handle.net/10962/59784 , vital:27649 , https://doi.org/10.1080/02602938.2016.1235133
  • Description: Participatory assessment is increasingly employed in higher education worldwide as a formative mechanism to support students’ active learning. But do students in an increasingly relationally diverse environment perceive that peer assessment of individuals’ contributions to group-work tasks enhances their learning? Recognising the impact of students’ conceptions on the quality of their learning, this study considers students’ perspectives of peer assessment of group-work contributions at a South African university. Questionnaires elicited students’ perspectives of and general attitudes towards assessment of and by their peers. A growing measure of discontent with the process of assessing peer contributions to group tasks emerged, including actual and perceived racial and gender stereotyping, and related rejection-sensitivity. These initial findings were checked against the students’ experiences in a report-and-respond process that enabled probing discussions of the interpretations. This paper examines and explores the implications of such identifications and receptions for learning engagement and group-work curriculum development in the context of a rapidly transforming higher education sector.
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  • Date Issued: 2016

Studies on comparison of aluminium-pillared montmorillonite clay with silica gel on adsorption of methylene blue in waste water

  • Authors: Mselana, Sinazo
  • Date: 2016
  • Subjects: Clay Silica gel Montmorillonite
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10353/8011 , vital:31462
  • Description: Adsorption equilibrium and kinetics of methylene blue (MB) onto silica gel and aluminum pillared montmorillonite was studied in a batch system. Variables of the system include contact time, salt concentration and initial methylene blue concentration. Langmuir and Freundlich isotherm models were applied to experimental equilibrium data of methylene blue adsorption. Both models were suitable for the parameters. The advantage of silica gel as applied to water treatment is its high porosity when compared to aluminum pillared montmorillonite clay. Water molecules adhere to the silica gels surface because it exhibits a lower vapour pressure than the surrounding air. When equilibrium of equal pressure is reached, no more adsorption occurs. Thus the higher the humidity of the surrounding air, the greater the amount of water that is adsorbed before equilibrium is reached. The increase in pressure loss on the silica gel filters is 1.5 - 2.0 times smaller than in the case of sand filters, Lorenc (2007).
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  • Date Issued: 2016

Study into the synthesis, characterisation and applications of Vanadium-based metal organic frameworks, using 1, 2, 4, 5-benzenetetracarboxylic acid

  • Authors: Feldmann, Wesley
  • Date: 2016
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/55245 , vital:26680
  • Description: This study focussed on the synthesis, characterisation and catalytic application of synthesised vanadium-based Metal-Organic Frameworks using 1,2,4,5-benzenetetracarboxylic acid as a ligand. A number of synthetic methods were tested in multiple attempts to synthesise a V-MOF, these included; ambient, gel, reflux and solvothermal methods of synthesis. Two products of interest were identified, an ambient synthesis produced a vanadium-based complex with the empirical formula: V2O2(Na2H2B4C).6H2O (RU-V2) and a solvothermal synthesis produced a MOF with the empirical formula: V2O2(H2O)2(B4C) (RU-V1). Both products were characterised using elemental analysis, infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry and X-ray powder diffraction. The catalytic activity of these products was tested, alongside the activity of the solid decavanadate ion, for the conversion of cyclohexene to cyclohexene oxide. The decavanadate ion was included to determine if the ion was catalytically active in the solid state, to potentially be used in the construction of a future MOF or V-complex. The reaction for the conversion of cyclohexene to cyclohexene oxide was chosen, as it has been previously conducted using a V-MOF and was found to be successful. The product of the reaction, the epoxide: cyclohexene oxide, is a very useful precursor for a number of reactions involved in the pharmaceutical industry, so developing catalysts which are able to convert cyclohexene to the epoxide with high yields and selectivities are well sought after in industry. The results of the catalytic reactions were varied, as the materials exhibited high yields and selectivities to the epoxide, but these results were only obtained when water was present in the reaction mixture. Water was able to bring about the cleavage of the bonds between the metal and ligand in a highly coordinated framework, at a faster rate than other solvents, such as decane. This ultimately leads to the structural decomposition of the entire complex or framework, depending upon the reaction time. The use of water was a double edged sword in that it was required to initiate the catalytic reaction, but was also the reason that the catalytic materials were noted to decompose over time. The solid decavanadate ion was only noted to exhibit homogeneous activity by dissolving into the small volume of water present in the reaction mixture. The study proved that using a multidentate ligand such as 1,2,4,5-benzenetetracarboxylic acid yielded products which were highly coordinated in nature and would therefore not have large open spaces associated with them, which is commonly observed with other MOFs. Instead the closed nature of the synthesised complexes and frameworks offered a different environment for catalytic reactions, where the small pores/channels had a controlling and inhibiting effect on the reaction. The conversion of cyclohexene to the epoxide is accompanied with a number of undesired side products, so when using the synthesised closed-natured MOF, it was found that there was a greater selectivity for the epoxide over other potential products. This indicates that close natured MOFs may find application in catalytic reactions which require high selectivities for a particular product.
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  • Date Issued: 2016

Study South Africa

  • Authors: International Education Association of South Africa (IEASA) , Jooste, Nico
  • Date: 2016
  • Subjects: Education, Higher -- South Africa , Universities and colleges -- South Africa , Technical Institutes -- South Africa , Vocational guidance -- South Africa
  • Language: English
  • Type: text , book
  • Identifier: http://hdl.handle.net/10962/64838 , vital:28614 , ISBN 9780620733601
  • Description: [Editor's Letter]: Study South Africa over time provided an annual overview of the South African Higher Education landscape as well as a forecast of some of the issues that could influence higher education in general and higher education internationalization in particular in South Africa for the year ahead. The 2016/17 issue being the 16th edition of Study South Africa provides an overview of the sector and a short description of all South African Public Higher Education institutions. This year, the Study SA Guide provides information about the system as well as articles that begin to address critical issues influencing the sector. It is foreseen that this would become a general feature in editions to come. The article that introduces a fundamental change in operations of South African Universities, beginning in 2016 and continuing into 2016 is the issue of the student protests on high tuition fees in South Africa. The #FEESMUSFALL movement introduced a topic that is fundamental to the internationalization of South African Higher Education. This event that began as a reaction to the increase in student fees for the 2016 academic year mutated into a social movement on university campuses throughout South Africa that challenged the way Universities function. Although not a mass based movement, but rather a movement driven by a desire to change the current social order in South Africa by a radical fringe, its focus is to use the plight of insufficient funding within South African Higher Education and in particular, focusing on funding of the poor. For a large part the issues raised by students is not in the domain of Higher Education, but a competency of Government and broader society. The influence of the constant disruption of academic activities on all South African University campuses resulted in a tendency to be an inwardly focused system where most of the energy is spent on local issues. South African Higher Education is known for its international connectedness and the way the international world accepted it into their fold as a critical player in a variety of fields, bringing a different voice to global debates. The hosting of Going Global by the British Council in May 2016 in Cape Town and the hosting of the Global Conference in August 2016 by IEASA in the Kruger National Park clearly demonstrated that South African Higher Education is globally an important player. The current situation in South Africa should be seen by the outside world as a process of internal re-evaluation. It is also a struggle to bring together the global and the local. It is a process that is currently driven by South African Higher Education institutions. Although the issues that triggered the revolt is local, the roots are global and our solution to the problem could become a guide to global higher education. It is thus necessary that all the partners of the South African system believe in South Africa as the carrier of goodwill and a message that is worth listening to. It is also necessary to rather engage with South African Universities to understand the issues and not to abandon them at this critical stage. This issue of Study South Africa should remain the connector with the global higher education system and the information provided will hopefully assist all those interested in keeping and building on this connection. , 16th Edition
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  • Date Issued: 2016

Subcellular localisation of Theiler's murine encephalomyelitis virus (TMEV) capsid subunit VP1 vis-á-vis host protein Hsp90:

  • Authors: Ross, Caroline J , Upfold, Nicole , Luke, Garry A , Tastan Bishop, Özlem , Knox, Caroline M
  • Date: 2016
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/148016 , vital:38702 , DOI: 10.1016/j.virusres.2016.06.003
  • Description: The VP1 subunit of the picornavirus capsid is the major antigenic determinant and mediates host cell attachment and virus entry. To investigate the localisation of Theiler's murine encephalomyelitis virus (TMEV) VP1 during infection, a bioinformatics approach was used to predict a surface-exposed, linear epitope region of the protein for subsequent expression and purification. This region, comprising the N-terminal 112 amino acids of the protein, was then used for rabbit immunisation, and the resultant polyclonal antibodies were able to recognise full length VP1 in infected cell lysates by Western blot. Following optimisation, the antibodies were used to investigate the localisation of VP1 in relation to Hsp90 in infected cells by indirect immunofluorescence and confocal microscopy.
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  • Date Issued: 2016

Successes and challenges of women's income generating projects in Zimbabwe

  • Authors: Hamunakwadi, Purity
  • Date: 2016
  • Subjects: Women in development -- Zimbabwe , Women -- Employment -- Zimbabwe , Economic development projects -- Zimbabwe , Women in rural development -- Zimbabwe
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10948/6810 , vital:21145
  • Description: Women’s income-generating projects are regarded as a critical area in promoting sustainable livelihoods in the lives of the poor. This study centres on a cattle project in Sadomba village in Nyanga District, Zimbabwe. The purpose of this study is to investigate the role and contributions of income-generating projects with regard to women; the necessary conditions for a successful cattle production project; the major challenges in women’s income-generating projects, and how income-generating projects can be strengthened, all in relation to this cattle project.The study is underpinned by the sustainable livelihood approach and literature on micro-financing of women’s projects in various countries. The study is based on qualitative methodology using a case study design and methods of data collection included semi-structured interviews, focus group discussions and participant observation. The data was analysed using thematic analysis and sub-themes that arose in the study and thereafter all the data was grouped by a process of coding. The results indicated that the Sadomba cattle project has benefited the project members in terms of income generation by the selling of cattle and milk, for agricultural purposes (draught power) and also income they obtained from hiring their cattle to other community members in rainy seasons. The income generated has assisted them to send their children to school and attain higher education.In addition, it promotes community engagement when they share paddocks and dip tanks. However, despite these benefits, they face a number of challenges such as long distances to the market, a lack of microcredit and the unavailability of exotic breeds. Therefore, there is need to integrate the conditions that are necessary for successful income generating projects to the Sadomba cattle project.
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  • Date Issued: 2016

Supplementary Material Synthesis and biological evaluation of (E)-cinnamic acid,(E)-2-styrylthiazole and (E)-2-[2-(naphthalen-1-yl) vinyl] thiazole derivatives

  • Authors: Olawode, Emmanuel O , Tandlich, Roman , Prinsloo, Earl , Isaacs, Michelle , Hoppe, Heinrich C , Seldon, Ronnett , Warner, Digby F , Steenkamp, Vanessa , Kaye, Perry T
  • Date: 2016
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/431778 , vital:72803 , xlink:href=" https://www.arkat-usa.org/get-file/59868/"
  • Description: The screening was conducted using multi-well plates which are suited for HeLa cells in the log phase of growth with final cell density > 10 cells/cm. Each experiment normally includes a blank control, containing medium without the cells.28,45 Non-contaminated HeLa cells (6.57 x 105 cells per well) in media were allowed to grow in the incubator under an atmosphere of 5% CO2 at 37 0C for 24 h. To each well was dispensed 200 µL of HeLa culture, containing 6.57 x 105 cells under LabEAir laminar flow hood (Vivid Air, South Africa); 20 µL of resazurin dye (Sigma TOX-8) and test compound (50 µL) were added, which were then incubated in the presence of 5% CO2 at 37 0C for 24 hours in a shaker, to enhance the distribution of the dye. The absorbance of each well was measured with Bio-tek Power Wave X fluorometer (Beijing, China), and increases in fluorescence was monitored at a wavelength of 590 nm, using an excitation wavelength of 560 nm.
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  • Date Issued: 2016

Supra-maximal speed interval training effect on a 40m standing start sprint and timed 3000m running performance in moderately trained female runners: Alterg anti-gravity treadmill running

  • Authors: Ellerbeck, Tim
  • Date: 2016
  • Subjects: Interval training , Women runners , Running -- Training
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10948/6772 , vital:21140
  • Description: The purpose of this study was to explore what the supra-maximal speed interval training effect was on a 40m standing start sprint and timed 3000m running performance was for two separate study groups when using either the AlterG® anti-gravity treadmill, or downhill running as a training intervention, for moderately trained female runners. The level of delayed onset of muscle soreness (DOMS) after each supra-maximal speed interval session was also captured. Data from 20 women was collected during initial pre-intervention testing; involving the 40m standing start sprint and 3000m timed trial run. During a four week training intervention the level of DOMS experienced by participants at increments of 24 hours, 48 hours and 72 hours, in each respective training group was recorded. Post-intervention testing was performed to once again measure the participants 40m standing start sprint and 3000m timed trial run values, results were analysed and compared to pre-intervention data.
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  • Date Issued: 2016

Surface characteristics of rock glaciers in the Jutulsessen, Dronning Maud Land, Antarctica

  • Authors: Rudolph, Elizabeth Magdalena
  • Date: 2016
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/2667 , vital:20314
  • Description: Rock glaciers are landforms that present downslope movement of debris under the influence of ice and gravity. These landforms can be used as paleo-climate indicators as well as proxies for climate change. Rock glaciers have been investigated in a variety of climates and landscapes, however continental Antarctica, Dronning Maud Land specifically, remains understudied. This thesis aimed to investigate and classify five rock glaciers observed in the Jutulsessen, Dronning Maud Land. The surface characteristics and geomorphology were assessed and used as generic classifiers. Size, shape and landscape association was established by field surveying and GIS, whilst sediment and clast characteristics were determined from sampling. A surface temperature profile was created from short-term high frequency temperature measurements. All of the rock glaciers exhibit either undulating surfaces or patterned ground, or both, which suggests active-layer related processes. Sediment particle size analysis is inconclusive. The 137Cs-content and fabric analysis suggest movement regimes similar to other rock glaciers with higher activity at the head, and variable movement directions at the toe. Relative “activeness” is inferred from morphology: Grjotlia, Grjotøyra and Vassdalen were classified as lobate, spatulate and tongue-shaped respectively with Grjotlia the most stable. A new morphological classification of ‘crown-shaped’ is suggested for Brugdedalen and Jutuldalen, and they also appear most active. The control of local climate on rock glacier mechanics is emphasised by the findings, and thus climatic interpolation from a single weather stations is not useful. Increased spatial and temporal coverage of sediment profiles, surface topography and active-layer characteristics could be used to elucidate the processes and controls of these landforms in the Antarctic.
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  • Date Issued: 2016

Surfing the waves of learning: enacting a Semantics analysis of teaching in a first-year Law course

  • Authors: Clarence, Sherran
  • Date: 2016
  • Language: English
  • Type: article , text
  • Identifier: http://hdl.handle.net/10962/59816 , vital:27654 , https://doi.org/10.1080/07294360.2016.1263831
  • Description: Students’ ability to build knowledge, and transfer it within and between contexts is crucial to cumulative learning and to academic success. This has long been a concern of higher education research and practice. A central part of this concern for educators is creating the conditions that enable their students' deep learning, as this is an area of significant struggle for many students. Legitimation Code Theory, in particular the dimension of Semantics, is proving useful in examining the kinds of conditions that may be necessary for students to build disciplinary knowledge cumulatively over time. Using illustrative data from one case study, this paper suggests that the conceptual tools offered by Semantics can provide academic lecturers and academic development staff with a set of conceptual and analytical tools which can enable them to ‘see’ and understand the ways in which knowledge can be cumulatively acquired and used, as well as the possible gaps between what they are teaching and what their students may be learning. The hope is that these new insights will provide new directions for change in teaching and learning where these may be needed.
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  • Date Issued: 2016

Sustainble public bus transport services in the Nelson Mandela Bay

  • Authors: Mntwini, Mkhonto
  • Date: 2016
  • Subjects: Urban transportation -- Economic aspects Urban transportation -- Research Transportation -- Customer services
  • Language: English
  • Type: Thesis , Masters , MBA
  • Identifier: http://hdl.handle.net/10948/11875 , vital:27000
  • Description: Purpose - Transport is a common constant variable found in just about every aspect of our lives as well as commercial activities; this is so because transport enables accessibility to people, places and goods. The effective management of public passenger transport operations is a more complex and all-embracing concept than what it may appear at first glance. Wider dispersed work place locations and urban sprawl is on the rise driven by among other factors the increased rate of globalisation. A unique opportunity is then presented in a developing country like South Africa for effective planning and management of public passenger bus operations. In the main, the purpose of this case study research was to develop a more sustainable public passenger transport bus operation to better connect people, places and goods. The organisation that will be studied is Blunden Coach Tours a luxury and semi-lux coach Tour operator, operating from the Nelson Mandela Bay. Design / Methodology / Approach – This study employed the case study research approach which was based on the qualitative research paradigm as such allowed for in-depth description and analysis of the case as well as related phenomena in real world context. The researcher focused only on the public passenger bus transport operations in Nelson Mandela Bay thus assuming a single context focus with a single case namely the development of a more sustainable public passenger transport operations in Nelson Mandela Bay. An embedded multiple unit of analysis strategy was employed selecting a sample of key persons responsible for strategic operational areas at Blunden Coach tours, sub-contractors and suppliers. The case study employed an in-depth probing interview process in an effort to better comprehend occurrences within the actual context of the events observed. The secondary sources of information gathered were used to structure and backup the interview questions. Practical implications – The case study enabled thought provoking insight which by virtue of South Africa’s historical socio-economic landscape offered an unusual perspective of the South African bus transport scene with a particular focus on environmental, regulatory and socio-economic sustainability considerations. A limitation to the study – The lack of responses to the interview questions from some of the key role players in the bus industry who were contacted as well as some of the respondents interviewed. The lack of responses to some of the interview questions could be perceived as a limitation to validating the Summary drawn from the study.
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  • Date Issued: 2016

Synthesis and biological evaluation of novel thiazole-based compounds

  • Authors: Olawode, Emmanual Oladayo
  • Date: 2016
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/62955 , vital:28325
  • Description: Thesis embargoed for one-year period. Expected date of release: April 2019
  • Full Text:
  • Date Issued: 2016

Synthesis and characterisation of lanthanide complexes with nitrogen- and oxygen-donor ligands

  • Authors: Madanhire, Tatenda
  • Date: 2016
  • Subjects: Rare earth metals
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10948/13127 , vital:27154
  • Description: The reactions of Ln(NO3)3∙6H2O (Ln = Pr, Nd or Er) with the potentially tridentate O,N,O chelating ligand 2,6-pyridinedimethanol (H2pydm) were investigated, and complexes with the formula, [Ln(H2pydm)2(NO3)2](NO3) (Ln = Pr or Nd) and [Er(H2pydm)3](NO3)3 were isolated. The ten-coordinate Pr(III) and Nd(III) compounds crystallise in the triclinic space group P-1 while the nine-coordinate Er(III) complex crystallises in the monoclinic system (P21/n). The reaction of PrCl3∙6H2O with H2pydm yielded the compound, [Pr(H2pydm)3](Cl)3, that crystallises in the monoclinic system, space group P21/c with α = 90, β = 98.680(1) and γ = 90°. The nine-coordinate Pr(III) ion is bound to three H2pydm ligands, with bond distances Pr-O 2.455(2)-2.478(2) Å and Pr-N 2.6355(19)-2.64(2) Å. X-ray crystal structures of all the H2pydm complexes reveal that the ligand coordinates tridentately, via the pyridyl nitrogen atom and the two hydroxyl oxygen atoms. The electronic absorption spectra of complexes show 4f-4f transitions. Rare-earth complexes, [Ln(H2L1)2(NO3)3] [Ln = Gd, Ho or Nd], were also prepared from a Schiff base. The X-ray single-crystal diffraction studies and SHAPE analyses of the Gd(III) and Ho(III) complexes shows that the complexes are ten-coordinate and exhibit distorted tetradecahedron geometries. With proton migration occurring from the phenol group to the imine function, complexation of the lanthanides to the ligand gives the ligand a zwitterionic phenoxo-iminium form. A phenolate oxygen-bridged dinuclear complex, [Ce2(H2L1)(ovan)3(NO3)3], has been obtained by reacting Ce(NO3)3∙6H2O with an o-vanillin derived Schiff base ligand, 2-((E)-(1-hydroxy-2-methylpropan-2-ylimino)methyl)-6-methoxyphenol (H2L1). Hydrolysis of the Schiff base occurred to yield o-vanillin, which bridged two cerium atoms with the Ce∙∙∙Ce distance equal to 3.823 Å. The Ce(III) ions are both tencoordinate, but have different coordination environments, showing tetradecahedron and staggered dodecahedron geometries, respectively. The reaction of salicylaldehyde-N(4)-diethylthiosemicarbazone (H2L2) in the presence of hydrated Ln(III) nitrates led to the isolation of two novel compounds: (E)-2[(ortho-hydroxy)benzylidene]-2-(thiomethyl)-thionohydrazide (1) and bis[2,3-diaza4-(2-hydroxyphenyl)-1-thiomethyl-buta-1,3-diene]disulfide. The latter is a dimer of the former. For this asymmetric Schiff base, 1 and the symmetric disulfide, classical hydrogen bonds of the O–H∙∙∙N as well as N–H∙∙∙S (for 1) type are apparent next to C–H∙∙∙O contacts. 4-(4-Bromophenyl)-1-(propan-2-ylidene)thiosemicarbazide was also prepared upon reacting 4-(4-bromophenyl)-3-thiosemicarbazide with acetone in the presence of ethanol and La(NO3)3∙6H2O. The C=S bond length was found to be 1.6686(16) Å which is in good agreement with other thioketones whose metrical parameters have been deposited with the Cambridge Structural Database. Classical hydrogen bonds of the N–H∙∙∙N and the N–H∙∙∙Br type are observed next to C–H∙∙∙S contacts. All synthesised compounds were characterised by microanalyses, single-crystal X-ray diffraction (except for [Nd(H2L1)2(NO3)3]), 1H NMR and IR spectroscopy.
  • Full Text:
  • Date Issued: 2016
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