Showing items 181 - 200 of 483

Your selections:

Geography of African development : an alternative curriculum

  • Authors: Fox, Roddy C
  • Date: 2005
  • Language: English
  • Type: Article
  • Identifier: vital:6679 , http://hdl.handle.net/10962/d1006666
  • Description: The Geography of African Development module is part of a year-long Third Year level geography course on Africa that has been offered at Rhodes University since 2002. The course is an exception to the dominant trend, both locally and internationally, which has witnessed a major decline in the teaching of regional geography and area studies. This paper examines how adopting a constructivist approach to the module's curriculum enabled learners to develop geographical skills at the same time as Africanising the curriculum.
  • Full Text:
  • Date Issued: 2005

Geology, structure and mineralization of the Onguati area, Karibib district, central Namibia

  • Authors: Viljoen, Wayne
  • Date: 2005
  • Subjects: Geology -- Namibia -- Karibib , Geology, Structural -- Namibia -- Karibib , Mines and mineral resources -- Namibia -- Karibib
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4964 , http://hdl.handle.net/10962/d1005576 , Geology -- Namibia -- Karibib , Geology, Structural -- Namibia -- Karibib , Mines and mineral resources -- Namibia -- Karibib
  • Description: The study area is situated in the Southern Central Zone of the intracontinental Pan-African Damara Orogen, approximately 20km NNE of Navachab Gold Mine in the Karibib district of Namibia. Mesothermal vein systems with Cu-Fe±Au mineralization are hosted by amphibolite facies calcitic and dolomitic marbles belonging to the Navachab Member of the Karibib Formation, and are best developed around the defunct Onguati Copper Mine, Brown Mountain and Western Workings areas. The Onguati study area is located in the saddle region of a moderately-to-gently inclined anticlinorium that experienced significant flattening during NNW-SSE-directed compression. The parallelogram arrangement of ENE- and NNE-trending thrusts and reverse faults that surround the Onguati study area may have developed when the direction of greatest principle subregional stress was oriented WSW-ESE. These structures define part of a Riedel shear system and later faults may have developed in the position of R and P shears respectively. Significant strain partitioning occurred between the ductile calcitic marbles which host the best developed, shear-related vein systems and the more competent dolomitic marbles. The thickness distributions of veins in the marbles of the Onguati Mine, Brown Mountain and Western Workings areas conform to a fractal or power-law distribution, The most intensely mineralized vein systems in the Onguati Mine and Western Workings calcitic marbles share similar low fractal dimensions (D-values) of 0.41 and 0.37 respectively. Veins In the calcitic and dolomitic marbles of the Brown Mountain area and in the dolomitic marbles of Western Workings have elevated D-values (>0.60) and are poorly mineralized. The low D-values «0.40) of the well mineralized vein systems reflect the higher degree of fracture connectivity. These vein systems were capable of efficiently draining and localizing large volumes of mineralizing fluids from crustal-scale structures. A metamorphic devolatization model is proposed where the entire Damaran metasedimentary and meta-volcanic package is seen as a large source area of very low concentrations of Cu, Au and other metals. Localization of deformation into crustal-scale faults and shear zones led to regional-scale hydrothermal fluid flow and focussing into the upstream fracture networks of the Onguati study area. Strong mineralization resulted when fluids encountered the reactive marble lithologies
  • Full Text:
  • Date Issued: 2005

Glasbury muscle men

  • Authors: Lewis, Colin A
  • Date: 2005
  • Language: English
  • Type: Article
  • Identifier: vital:6175 , http://hdl.handle.net/10962/d1012368
  • Description: Colin Lewis was Professor of Geography at Rhodes University, Grahamstown, South Africa from 1989 until his retirement at the end of 2007. In 1990, with the strong support of the incumbent Vice-Chancellor, Dr Derek Henderson, he instigated the Certificate in Change Ringing (Church Bell Ringing) in the Rhodes University Department of Music and Musicology - the first such course to be offered in Africa. Since that date he has lectured in the basic theory, and taught the practice of change ringing. He is the Ringing Master of the Cathedral of St Michael and St George, Grahamstown, South Africa.
  • Full Text: false
  • Date Issued: 2005

Growth, feeding and sex change in the sequential protandric shrimp Nauticaris marionis Bate 1888 at the Prince Edward Islands (Southern Ocean)

  • Authors: Vumazonke, Lukhanyiso Unam
  • Date: 2005
  • Subjects: Shrimps -- Prince Edward Islands , Shrimps -- Feeding and feeds , Shrimps -- Nutrition , Shrimps -- Growth
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5704 , http://hdl.handle.net/10962/d1005390 , Shrimps -- Prince Edward Islands , Shrimps -- Feeding and feeds , Shrimps -- Nutrition , Shrimps -- Growth
  • Description: Demographic parameters and the general biology of the subantarctic shrimp Nauticaris marionis from the Prince Edward Islands were investigated. The carapace length is the most accurate indicator of body size and it was confirmed that N. marionis is a partially protandric hermaphrodite. Gravid females of N. marionis observed mainly in March with negligible hatching persisting until April/May. The majority of juveniles develop into males. Juveniles are characterised by an appendage on the endopodite of the first pleopod called the appendix interna or a.i.1. Juveniles that develop into males do so by growing a further appendage on the endopodite of the second pleopod. This appendage characterises males and is called the appendix masculina (or a.m.). Juveniles may develop directly into primary females through the development of an ovary and the loss of the a.i.1. The sequence differs among individuals, with some developing the ovary before losing the a.i.1 and others losing the a.i.1 first. Loss of the a.i.1 appears to be by shedding during a single moult, rather than by atrophy. Females can also develop by an alternative route as secondary females. Such animals first become males with an a.m. and then develop an ovary, thus forming an intermediate form called a tertium quid, or “third thing”. Again, there are two forms of tertium quid. Tertia quae a have the a.m. as well as the a.i.1. Tertia quae b have the a.m. in combination with an ovary but no a.i.1. Either form of tertium quid can develop into a secondary female through loss of the a.m., and in the case of the tertium quid a, loss of the a.i.1. It is unclear whether sexual differentiation occurs in the plankton or just after N. marionis settles on the benthos. The results of gut content analysis suggest that N. marionis is an opportunistic feeder, preying on a variety of prey with a preference for detritus, benthic amphipods and gastropods. Cannibalism of conspecific pleopods by large individuals of N. marionis occurred mostly in females, particularly in incubation containers. Cannibalism also occurs in males, and its occurrence depends on individual size, not gender. No diel patterns were observed in the feeding activity of N. marionis. In situ daily rations of males (carapace length <7mm) and females (>7mm) were equivalent to ≈10% and ≈5% of body dry weight, respectively. The von Bertalanffy growth curve parameters were empirically identified, by cohort analysis of data collected during 4 years, as K = 0.22239/year, L[subscript]∞ = 14.05789mm, t₀ = -0.05174, L₀ = 0.16083mm. N. marionis can survive up to seven years under natural conditions.
  • Full Text:
  • Date Issued: 2005

Habitat suitability and behaviour of springbok (Antidorcas marsupialis) at Augrabies Falls National Park, South Africa

  • Authors: Reid, Caroline
  • Date: 2005
  • Subjects: Springbok -- Habitat suitability index models -- South Africa -- Augrabies Falls National Park , Springbok -- Behavior -- South Africa -- Augrabies Falls National Park
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:11079 , http://hdl.handle.net/10948/362 , Springbok -- Habitat suitability index models -- South Africa -- Augrabies Falls National Park , Springbok -- Behavior -- South Africa -- Augrabies Falls National Park
  • Description: Habitat selection may be considered a behavioural consequence of an individual actively selecting where it lives or passively persisting in a certain habitat. There are a variety of approaches to assessing habitat selection, including relating densities to predefined habitats and the characteristics of these habitats, measuring the behaviour of animals within predefined habitats in order to assess the relative benefits to the animal and comparing these between habitats, and using optimality theory to allow the animal to provide measures of its preference for particular habitats or patches. Each approach provides different perspectives on an animal’s choice and use of habitat, with some approaches working more effectively with certain species or habitats than others. There have, however, been no attempts to apply all these approaches to a single species at a single site. The objective of this study was therefore to apply the three above-mentioned approaches to assess habitat use and quality to a single species, the springbok (Antidorcas marsupialis) at the Augrabies Falls National Park (AFNP), on the northern bank of the Orange River, in order to provide the basis for further work on comparing and integrating these approaches. The relative abundance of springbok in Augrabies Falls National park was used to develop a habitat suitability model for the park, and thus determine the habitat variables that influenced habitat suitability. Isodar analysis revealed information on the mechanisms underlying habitat preference. Behavioural models were developed to improve our understanding of how springbok behaviour changes in relation to the habitat, and incorporated the variables identified in the habitat suitability model. The different spatial and temporal scales influencing springbok habitat selection were determined using optimal foraging theory and giving-up densities. Springbok preferred open habitats providing high food quality. Springbok behaviour was related to the foraging and predation risk characteristics of the habitat, and springbok varied their temporal and spatial utilisation so as to minimise their risk of predation and maximise their food intake. The habitat suitability model, behaviour models and giving-up densities were compared for ease of use and applicability. Using giving-up densities to reveal habitat suitability had greater applicability and was both efficient and objective.
  • Full Text:
  • Date Issued: 2005

Haleluya

Harnessing newsroom knowledge:

  • Authors: Berger, Guy
  • Date: 2005
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/159244 , vital:40280 , https://hdl.handle.net/10520/EJC146387
  • Description: Nairobi's Nation newspaper has a sophisticated content management system (CMS); Grahamstown's Grocott's Mail has a patchwork of paper and computer tech. In Harare, the Mirror and the Independent newspapers fall somewhere in between. But what all of them lack is a way to use information communication technologies for knowledge management.
  • Full Text:
  • Date Issued: 2005

Hijacking feminism: representations of the new woman in South African television advertising practice

  • Authors: Klokow, Nicole Ann
  • Date: 2005
  • Subjects: Feminism and mass media -- South Africa , Television advertising -- South Africa
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:8372 , http://hdl.handle.net/10948/381 , Feminism and mass media -- South Africa , Television advertising -- South Africa
  • Description: This study examines the extent to which feminism has been appropriated by the consumer culture. As the relationship between consumerism and patriarchy continues to dominate global economic and social practices, this appropriation points to a denial of the social and political importance of the feminist movement. An acknowledgement of our own complicity in the perpetuation of a sexist, racist and classist ideology – along with an understanding of the complicity of the media – is crucial in explaining relations of domination within our society (Thompson 1990). A study of television advertising practice allows us to “explore meaning as a social product, enmeshed in webs of power” (Jordan and Wheedon 1995:543). Consumer ‘freedom’ is the compulsory freedom (Slater 1997), as we buy as many symbols as products. This study shows that for all the ‘strides’ feminism has made, media images of women are largely traditional, prescriptive (although an ironic distance is often implied) or overtly sexualised. Feminism is never mentioned, as women’s gains are presented as ahistorical in a ‘post-feminist’ world. Third wave feminism is an attempt to embrace all feminisms and feminists, working to inject some substance and truth behind advertising’s feminist veneer.
  • Full Text:
  • Date Issued: 2005

How policy discourses and contextual realities influence environmental teaching and learning processes in early childhood development: a case study of the Raglan Road child care centre

  • Authors: Vallabh, Priya
  • Date: 2005
  • Subjects: Early childhood education -- South Africa , Health education -- South Africa , Environmental education -- Study and teaching -- South Africa , Day care centers -- South Africa , Child development
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1559 , http://hdl.handle.net/10962/d1003441 , Early childhood education -- South Africa , Health education -- South Africa , Environmental education -- Study and teaching -- South Africa , Day care centers -- South Africa , Child development
  • Description: This case study considers the relationship between context, school policy and environmental teaching and learning processes at a community-based early childhood development centre in South Africa. The study recognises that educational practices in the early childhood development field are shaped by historical, cultural, economic and political realities at both local and national levels. It is from the understanding that each school is a unique composition of these shaping factors that the research was designed to consider the community-based school participating in this study. By compiling a contextual profile, this study attempts to consider dominant contextual factors affecting the school. Through the critical discourse analysis of a school policy document, this study considers local level policy, and through the literature chapter, national policy. Teacher interviews provide insight into teacher understanding of school policy in response to contextual issues, as well as providing insight into how teachers perceive their translation of policy into teaching practice. Observations of lessons in the centre provided an. opportunity to see how context and policy translated into and influenced environmental teaching and learning processes. This study looks at how environmental education is addressed in the Raglan Road Child Care Centre, and provides insight into how environmental education within the context of the school and in relation to school policy may be strengthened. It comments on the tensions and ambivalences arising from the relationships between context, policy and environmental teaching and learning processes and makes recommendations to address these ambivalences in ways that are contextually relevant. The main recommendations were designed to be practically useful for the school involved in the study and are focused around engaging the ambivalences emerging from this study to open up 'spaces' for deliberating environmental teaching and learning processes and other tensions arising out of the study at an ECD level. Recommendations included: 1) engaging with the strong development focus in school policy and the educational focus in national policy and teacher discourse; 2) deliberating the ways in which school policy and national policy respond to risk; 3) engaging with the ambivalence in the school-parent relationship; 4) the re-alignment of the explicit curriculum and broadening the contextually-based view of whole child development; and 5) engaging the ambivalence in approaches to education at the centre.
  • Full Text:
  • Date Issued: 2005

Hydrogen peroxide oxidation of 2-chlorophenol and 2, 4, 5-trichlorophenol catalyzed by monomeric and aggregated cobalt tetrasulfophthalocyanine

  • Authors: Agboola, Bolade , Ozoemena, Kenneth I , Nyokong, Tebello
  • Date: 2005
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/289249 , vital:56612 , xlink:href="https://doi.org/10.1016/j.molcata.2004.10.041"
  • Description: Cobalt tetrasulfophthalocyanine (CoTSPc) was used to catalyze the oxidation of 2-chlorophenol (2-CP) and 2,4,5-trichlorophenol (TCP) using hydrogen peroxide (H2O2) as the oxidant. This CoTSPc catalyzed hydrogen peroxide oxidation of chlorophenols resulted in the formation of different types of oxidation products depending on the solvent conditions. In water/methanol conditions (where CoTSPc is mainly monomeric, and unionized forms of the phenols), phenol and hydroquinone were the main oxidation products, while in phosphate buffer solutions (pH 7 and 10 for TCP and 2-CP, respectively, where CoTSPc is mainly aggregated, and ionized forms of the phenols), benzoquinone was the main product. In contrast to CoTSPc, other MTSPc complexes studied (AlTSPc, CuTSPc and NiTSPc) exhibited no detectable catalytic effect on the oxidation of chlorophenols under the experimental conditions employed, thus proving the effect of the central metal ions on efficient catalysis of chlorophenol. Reaction pathways are proposed based on the relative time of oxidation products formation.
  • Full Text:
  • Date Issued: 2005

Identification of cis-elements and transacting factors involved in the abiotic stress responses of plants

  • Authors: Maclear, Athlee
  • Date: 2005 , 2013-06-10
  • Subjects: Plants -- Effect of stress on , Proteins -- Analysis , Bioinformatics , DNA , Plant genetics
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4074 , http://hdl.handle.net/10962/d1007236 , Plants -- Effect of stress on , Proteins -- Analysis , Bioinformatics , DNA , Plant genetics
  • Description: Many stress situations limit plant growth, resulting in crop production difficulties. Population growth, limited availability and over-utilization of arable land, and intolerant crop species have resulted in tremendous strain being placed on agriculturalists to produce enough to sustain the world's population. An understanding of the principles involved in plant resistance to environmental stress will enable scientists to harness these mechanisms to create stress-tolerant crop species, thus increasing crop production, and enabling the farming of previously unproductive land. This research project uses computational and bioinformatics techniques to explore the promoter regions of genes, encoding proteins that are up- or down-regulated in response to specific abiotic stresses, with the aim of identifying common patterns in the cis-elements governing the regulation of these abiotic stress responsive genes. An initial dataset of fifty known genes encoding for proteins reported to be up- or down-regulated in response to plant stresses that result in water-deficit at the cellular level viz. drought, low temperature, and salinity, were identified, and a postgreSQL database created to store relevant information pertaining to these genes and the proteins encoded by them. The genomic DNA was obtained where possible, and the promoter and intron regions identified. The Neural Network Promoter Prediction (NNPP) software package was used to predict the transcription start signal (TSS) and the promoter searching software tool, TESS (Transcription Element Search Software) used to identify known and user-defined cis-elements within the promoter regions of these genes. Currently available promoter prediction software analysis tools are reported to predict one promoter per kilobase of DNA, whilst functional promoters are thought to only occur one in 30-40 kilobases, which indicates that a large perccntage of predictions are likely to be false positives (pedersen et. al., 1999). NNPP was chosen as it was rated as the highest performing promoter prediction software tool by Fickett and Hatzigeorgiou (1997) in a thorough review of eukaryotic promoter prediction algorithms, however results were less than promising as very few predicted TSS were identified in the area 50 bps up- and downstream of the gene start site, where biologically functional TSSs are known to occur (Reese, 2000; Fickett and Hatzigeorgiou, 1997). TESS results seemed to support the hypothesis that drought, low-temperature and high salinity plant stress response proteins have similar as-elements in their promoter regions, and suggested links to various other gene regulation mechanisms viz. gibberellin-, light-, auxin- and development-regulated gene expression, highlighting the vast complexity of plant stress response processes. Although far from conclusive, results provide a valuable basis for future comparative promoter studies that will attempt to deduce possible common transcriptional initiation of abiotic stress response genes. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
  • Full Text:
  • Date Issued: 2005

Imbhola yesiXhosa traditional Xhosa cosmetics:

  • Authors: Cocks, Michelle L , Dold, Anthony P
  • Date: 2005
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/141370 , vital:37966 , http://pza.sanbi.org/sites/default/files/info_library/imbhola_yesixhosa_pdf.pdf
  • Description: Plants have been used for cosmetic purposes since time immemorial. The earliest known cosmetics come from the First Dynasty of Egypt, about 3100-2907 BC. Since the ancient Egyptians who used olive oil perfumed with aromatic plants to keep their skin supple, humans have been using plant extracts for cleansing and beautifying purposes.
  • Full Text:
  • Date Issued: 2005

Immobilized cobalt (II) phthalocyanine–cobalt (II) porphyrin pentamer at a glassy carbon electrode

  • Authors: Ozoemena, Kenneth I , Zhao, Zhixin , Nyokong, Tebello
  • Date: 2005
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/300322 , vital:57916 , xlink:href="https://doi.org/10.1016/j.elecom.2005.04.019"
  • Description: This communication describes the electrochemistry of a novel cobalt phthalocyanine–cobalt porphyrin (cobalt(II)phthalocyanine–cobalt(II)tetra(5-phenoxy-10,15,20-triphenylporphyrin)) (CoPc-(CoTPP)4) immobilised onto a glassy carbon electrode (GCE). The GCE-CoPc-(CoTPP)4 displayed high efficiency as a potential amperometric sensor for hydrogen peroxide (H2O2) in neutral and alkaline pH conditions. Electrochemical and electrocatalytic properties of the pentamer seem to depend mostly on the central CoPc, and partly, on the synergistic effect of the CoPc/CoPP units. The GCE-CoPc-(CoTPP)4 showed very fast amperometric response (∼1 s), with linearities up to ⩾1.50 mM, low detection limits (μM range) and stability (8 weeks) towards the amperometric determination of laboratory and medical solutions of H2O2.
  • Full Text:
  • Date Issued: 2005

Impacts of wildlife and cattle grazing on spider (araneae) biodiversity in a highland savanna ecosystem, in Laikipia, Central Kenya

  • Authors: Warui, Charles Mwaura
  • Date: 2005
  • Subjects: Spiders -- Kenya Environmental monitoring -- Kenya Savanna ecology -- Kenya Biodiversity -- Kenya Species diversity -- Kenya Wildlife management -- Kenya Herbivores -- Ecology -- Kenya
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:5712 , http://hdl.handle.net/10962/d1005398
  • Description: Spiders were sampled at Mpala Research Centre, Laikipia, Kenya by pitfall-trapping and sweep-netting from May 2001 to July 2002, at a Kenyan Long-term Exclosure Experiment. The aim was to establish species composition, checklist and examine spider responses to disturbances caused by cattle, megaherbivores (giraffe and elephants) and mesoherbivores (other ungulates) by looking at three levels of resolution, namely the overall community, guilds and individual species. This is the first controlled replicated experimental study on the effects on invertebrates (spiders) by different land uses (access by large herbivores). A total of 10,487 individuals from 132 species belonging to 30 families were recorded. The family Salticidae had the highest number of species (24), followed by Gnaphosidae (20), Araneidae and Lycosidae (15 each), Theridiidae and Thomisidae (8 each) and Zodariidae (4). Most of the other families had fewer than 4 species. Throughout the study period, species not previously sampled emerged after rainfall peaks. Exclosure treatments affected plant cover, spider diversity and total species mainly through the effects of cattle, whose presence significantly reduced relative vegetation cover. An increase in vegetation cover significantly increased the diversity, total species and species evenness of the overall spider community (total samples data set). Megaherbivores and mesoherbivores had no effects on overall spider diversity. Relative vegetation cover explained approximately 20-30% of variation in community diversity, species richness and species evenness. At the guild level of resolution, the exclosure treatments had no significant effects on diversity, species richness and species evenness of web builders, plant wanderers and ground wanderers. Plant wanderers were significantly and positively correlated with relative vegetation cover, which explained 17% of variation in their diversity. Six individual species responded strongly and in contrasting ways to the same environmental variables, indicating that this level was more sensitive to environmental changes than guilds or the overall spider community. Spider diversity, relative vegetation cover and rainfall varied at a temporal scale of months and not at a spatial scale of hundreds of metres. Only species diversity and species richness from sweep-netting samples and total species from pitfall-trapping varied significantly at a spatial scale of hundreds of metres. Ordination analysis revealed that sweep-netting samples were a better indicator of grazing impacts than pitfalltrapping or combined samples and grouped to reflect cattle grazing, non-cattle grazing and to a small extent the control treatments. Other ordination analyses showed that only samples from sweep-netting and not from pitfall-trapping, were spatially partitioned at a scale of hundreds of metres. This study concludes that the spider fauna of black cotton soil habitats is rich and useful for environmental monitoring and that monitoring of several individual species as indicator of grazing impacts in savanna could be useful and relatively easy.
  • Full Text:
  • Date Issued: 2005

Implementing an EPrints repository system at a small South African university

  • Authors: Vermaak, Irene
  • Date: 2005
  • Language: English
  • Type: Text
  • Identifier: vital:6980 , http://hdl.handle.net/10962/d1012408
  • Description: This presentation gives a descriptive and analytical overview of the implementation of the Rhodes eResearch Repository system at Rhodes University, building on an ETD programme started in 1998. This project involves staff from Rhodes University Library and the Information Technology Division, with the approval of the Dean of Research. With the support of Management and a strong university IT culture of using open source software, Rhodes University Library planned the implementation of the system without major bureaucratic obstacles. We did, however, experience limited budgetary support and severe staff constraints. This poster aims to encourage institutions with limited resources to start IR programmes and emphasizes the short space of time required “to get up and go”.
  • Full Text:
  • Date Issued: 2005

Implementing the CoSaWoE models in a commercial workflow product

  • Authors: Erwee, Carmen
  • Date: 2005
  • Subjects: Computers -- Access control , Workflow , Computer security , Data protection
  • Language: English
  • Type: Thesis , Masters , MTech
  • Identifier: vital:9732 , http://hdl.handle.net/10948/169 , Computers -- Access control , Workflow , Computer security , Data protection
  • Description: Workflow systems have gained popularity not only as a research topic, but also as a key component of Enterprize Resource Planning packages and e- business. Comprehensive workflow products that automate intra- as well inter-organizational information flow are now available for commercial use. Standardization efforts have centered mostly around the interoperability of these systems, however a standard access control model have yet to be adopted. The research community has developed several models for access control to be included as part of workflow functionality. Commercial systems, however, are still implementing access control functionality in a proprietary manner. This dissertation investigates whether a comprehensive model for gain- ing context-sensitive access control, namely CoSAWoE, can be purposefully implemented in a commercial workflow product. Using methods such as an exploratory prototype, various aspects of the model was implemented to gain an understanding of the di±culties developers face when attempting to map the model to existing proprietary software. Oracle Workflow was chosen as an example of a commercial workflow product. An investigtion of the features of this product, together with the prototype, revealed the ability to affect access control in a similar manner to the model: by specifying access control constraints during administration and design, and then enforcing those constraints dynamically during run-time. However, only certain components within these two aspects of the model directly effected the commercial workflow product. It was argued that the first two requirements of context-sensitive access control, order of events and strict least privilege, addressed by the object design, role engineering and session control components of the model, can be simulated if such capabilities are not pertinently available as part of the product. As such, guidelines were provided for how this can be achieved in Oracle Workflow. However, most of the implementation effort focussed on the last requirement of context-sensitive access control, namely separation of duties. The CoSAWoE model proposes SoD administration steps that includes expressing various business rules through a set of conflicting entities which are maintained outside the scope of the workflow system. This component was implemented easily enough through tables which were created with a relational database. Evaluating these conflicts during run-time to control worklist generation proved more di±cult. First, a thorough understanding of the way in which workflow history is maintained was necessary. A re-usable function was developed to prune user lists according to user involvement in previous tasks in the workflow and the conflicts specified for those users and tasks. However, due to the lack of a central access control service, this re- usable function must be included in the appropriate places in the workflow process model. Furthermore, the dissertation utilized a practical example to develop a prototype. This prototype served a dual purpose: firstly, to aid the author's understanding of the features and principles involved, and secondly, to illustrate and explore the implementation of the model as described in the previous paragraphs. In conclusion the dissertation summarized the CoSAWoE model's compo- nents which were found to be product agnostic, directly or indirectly imple- mentable, or not implemented in the chosen workflow product. The lessons learnt and issues surrounding the implementation effort were also discussed before further research in terms of XML documents as data containers for the workfow process were suggested.
  • Full Text:
  • Date Issued: 2005

In vitro release of ketoprofen from proprietary and extemporaneously manufactured gels

  • Authors: Tettey-Amlalo, Ralph Nii Okai
  • Date: 2005
  • Subjects: Transdermal medication , Drug delivery systems , High performance liquid chromatography , Nonsteroidal anti-inflammatory agents , Rheumatoid arthritis -- Treatment
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:3797 , http://hdl.handle.net/10962/d1003275 , Transdermal medication , Drug delivery systems , High performance liquid chromatography , Nonsteroidal anti-inflammatory agents , Rheumatoid arthritis -- Treatment
  • Description: Ketoprofen is a potent non-steroidal anti-inflammatory drug which is used for the treatment of rheumatoid arthritis. The oral administration of ketoprofen can cause gastric irritation and adverse renal effects. Transdermal delivery of the drug can bypass gastrointestinal disturbances and provide relatively consistent drug concentrations at the site of administration. The release of ketoprofen from proprietary gel products from three different countries was evaluated by comparing the in vitro release profiles. Twenty extemporaneously prepared ketoprofen gel formulations using Carbopol® polymers were manufactured. The effect of polymer, drug concentration, pH and solvent systems on the in vitro release of ketoprofen from these formulations were investigated. The gels were evaluated for drug content and pH. The release of the drug from all the formulations obeyed the Higuchi principle. Two static FDA approved diffusion cells, namely the modified Franz diffusion cell and the European Pharmacopoeia diffusion cell, were compared by measuring the in vitro release rate of ketoprofen from all the gel formulations through a synthetic silicone membrane. High-performance liquid chromatography and ultraviolet spectrophotometric analytical techniques were both used for the analysis of ketoprofen. The validated methods were employed for the determination of ketoprofen in the sample solutions taken from the receptor fluid. Two of the three proprietary products registered under the same manufacturing license exhibited similar results whereas the third product differed significantly. Among the variables investigated, the vehicle pH and solvent composition were found have the most significant effect on the in vitro release of ketoprofen from Carbopol® polymers. The different grades of Carbopol® polymers showed statistically significantly different release kinetics with respect to lag time. When evaluating the proprietary products, both the modified Franz diffusion cell and the European Pharmacopoeia diffusion cell were deemed adequate although higher profiles were generally obtained from the European Pharmacopoeia diffusion cells. Smoother diffusion profiles were obtained from samples analysed by high-performance liquid chromatography than by ultraviolet spectrophotometry in both diffusion cells. Sample solutions taken from Franz diffusion cells and analysed by ultraviolet spectrophotometry also produced smooth diffusion profiles. Erratic and higher diffusion profiles were observed with samples taken from the European Pharmacopoeia diffusion cell and analysed by ultraviolet spectrophotometry. The choice of diffusion cells and analytical procedure in product development must be weighed against the relatively poor reproducibility as observed with the European Pharmacopoeia diffusion cell.
  • Full Text:
  • Date Issued: 2005

In-kernel cryptographic executable verification

  • Authors: Motara, Yusuf, M , Irwin, Barry V W
  • Date: 2005
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/429049 , vital:72556 , https://doi.org/10.1007/0-387-31163-7_25
  • Description: This paper discusses the problems posed by Trojan horses and unauthorized code, and reviews existing solutions for dealing with them. A technique involving the in-kernel verification of executables is proposed. Its advantages include simplicity, transparency, ease of use and minimal setup time. In addition, the technique has several applications, including assisting with honeypot implementations, incident response and forensic investigations.
  • Full Text:
  • Date Issued: 2005

In-kernel cryptographic executable verification

  • Authors: Motara, Yusuf, M , Irwin, Barry V W
  • Date: 2005
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/429937 , vital:72653 , https://doi.org/10.1007/0-387-31163-7_25
  • Description: This paper discusses the problems posed by Trojan horses and unau-thorized code, and reviews existing solutions for dealing with them. A technique involving the in-kernel verification of executables is pro-posed. Its advantages include simplicity, transparency, ease of use and minimal setup time. In addition, the technique has several applications, including assisting with honeypot implementations, incident response and forensic investigations.
  • Full Text:
  • Date Issued: 2005

Incorporating indigenous management in rock art sites in KwaZulu-Natal

  • Authors: Ndlovu, Ndukuyakhe
  • Date: 2005
  • Subjects: Rock paintings -- Drakenberg Mountains , Cave paintings -- Drakensberg Mountains , San (African people) -- Art , Art, Prehistoric -- Drakensberg Mountains , Art, Prehistoric -- South Africa , Heritage tourism -- South Africa
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2089 , http://hdl.handle.net/10962/d1002652 , Rock paintings -- Drakenberg Mountains , Cave paintings -- Drakensberg Mountains , San (African people) -- Art , Art, Prehistoric -- Drakensberg Mountains , Art, Prehistoric -- South Africa , Heritage tourism -- South Africa
  • Description: The majestic mountains of the uKhahlamba Drakensberg, formed many millennia ago were home to the Bushmen[footnote 1] or San people. They lived at these mountains for thousands of years before they were colonised by the Bantu speakers and the Europeans. Academic writings for many years have perpetuated the thinking that Bushman people were largely extinct. The dominance of this view in the academic writings was encouraged by historical evidence that Europeans and Bantu speakers hunted and killed Bushmen over the last several centuries. Researchers argue that the extermination of the Bushmen was because they were less human in the eyes of the foreigners, due to cattle raiding. There is still some element of this thinking amongst today’s academics, although research in the last decade is questioning this thinking. The question of whether descendants do exist is relevant to issues of rights of access to ancestral sacred sites, in particular rock art sites. At present, access to rock art sites is granted on qualification as an authentic fee-paying tourist (or affordability) rather than on group rights to a cultural heritage resource (cultural rights). Based on this, I argue that access to rock art sites is based on qualification rather than by right. This is largely driven by an approach that emphasises the physical conservation and financial sustainability of a site, rather than its spiritual maintenance. It has become clear that the interests in rock art by tourists and Bushman descendants are distinct from each other. Tourists have an aesthetic significance for rock art while Bushmen descendants have a spiritual significance for the paintings. Beyond any doubt, the physically based and financially driven approach has brought new challenges to today’s Bushmen descendants, whom in reaffirming their identities now have a new challenge to overcome. Not only are the rock art sites physically threatened but also they have lost much of their spiritual powers. Their fate lies in the hands of heritage officers who must determine access rights to the painted shelters. Both the National Heritage Resources Act and the KwaZulu-Natal Heritage Act acknowledge living heritage. However, the existence of this heritage is judged against the physical approach to rock art management. If the practises of descendants are perceived to be a threat to the rock art, they will not be approved. The case of the Duma is a classic example. Prior to the ritual ceremony at Game Pass Shelter, Kamberg, they were informed of the minimum standards for opening a rock art site to public and rules of how people should behave while visiting painted shelters. While it was evident that there are problems with the two approaches, the spiritual and physical approach, discussed in the thesis, it is important that solutions are identified. I do not believe that one approach on its own will be good enough, for reasons discussed in the thesis. Instead, the two approaches should be implemented together to compliment each other by identifying common grounds. I provide strategies as to how I believe that such a common ground can be reached. In addition, I provide my own analytical thinking as to how these strategies can be achieved. There is no general consensus over which term is appropriate. Both terms are considered by some academics to be derogatory or pejorative (Chennels 2003). San means vagabond and was given to the Bushmen by Khoi-Khoi people, because they considered themselves of a better social class, as they had domesticated animals and were more sedentary than Bushmen. However, according to WIMSA (Thoma 2003) the word San is derived from the Hai||om language meaning “people who gather”. It is normally written Saan but it has been accepted to write San. In 1993 the San requested to be called San when referred to as an entire group. If one refers to individual people/groups they like to be called by their language and cultural name i.e. Khwe, !Kung, !Xun, Ju|’hoansi, ‡Khomani, N|u, |’Auni, Hai||om, etc In this thesis, Bushmen is a preferred term, because it is a better-known term among the people who are central to this study. It is used without any insulting connotations attached to the term.
  • Full Text:
  • Date Issued: 2005
  • Disclaimer
  • Privacy
  • Copyright
  • Contact