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The xfn connection management and control protocol

  • Authors: Foss, Richard , Gurdan, Robby , Klinkradt, Bradley , Chigwamba, Nyasha
  • Date: 2011
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/427137 , vital:72417 , https://www.aes.org/e-lib/browse.cfm?elib=16143
  • Description: With the advent of digital networks that link audio devices, there is a need for a protocol that integrates control and connection management, enables the streaming of all media content such as audio and video between devices from different manufacturers, and that provides a common approach to the control of these devices. This paper describes such a protocol, named XFN, currently being standardized as part of the AES X170 project. XFN is an IP-based peer to peer network protocol, in which any device on the network may send or receive connection management, control, and monitoring messages. Essential to the XFN protocol is the fact that each parameter in a device can be addressed via a hierarchical structure that reflects the functional layout of the device.
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  • Date Issued: 2011

The zoogeography of the cetaceans in Algoa Bay

  • Authors: Melly, Brigitte Leigh
  • Date: 2011
  • Subjects: Cetacea -- South Africa -- Algoa Bay , Cetacea -- Behavior -- South Africa -- Algoa Bay , Cetacea -- South Africa -- Algoa Bay -- Geographical distribution , Cetacea -- Counting -- South Africa -- Algoa Bay
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4858 , http://hdl.handle.net/10962/d1005534 , Cetacea -- South Africa -- Algoa Bay , Cetacea -- Behavior -- South Africa -- Algoa Bay , Cetacea -- South Africa -- Algoa Bay -- Geographical distribution , Cetacea -- Counting -- South Africa -- Algoa Bay
  • Description: The most recent study on cetaceans in Algoa Bay, South Africa, was conducted over 14 years ago. Consequently, knowledge of the cetacean species visiting this bay is currently based on incidental observations and stranding data. A number of developments in recent years: a deepwater port, proposed oil refinery, increased boating and fishing (commercial and recreational), a proposed Marine Protected Area, and the release of a whale-watching permit, all of which may impact these animals in some way, highlight the need for a baseline study on cetaceans. Therefore, the aim of this study was to determine the spatial and temporal distribution, and habitat preference of cetaceans in Algoa Bay. Boat-based surveys were conducted monthly between March 2009 and July 2010. At each sighting the GPS location, species, group size and composition, and behaviour were recorded. Using GIS, the sighting data was related to data layers of geographical variables such as sea surface temperature, depth and sea-floor substrate. Approximately 365 hours of search effort were completed over 57 surveys, with a total of 346 sightings. Species observed were: southern right whales (Eubalaena australis), humpback whales (Megaptera novaeangliae), Bryde’s whales (Balaenoptera brydei), Indian Ocean bottlenose dolphins (Tursiops aduncus), Indo-Pacific humpback dolphins (Sousa chinensis), and longbeaked common dolphins (Delphinus capensis). Southern right whales were observed during austral winter, utilising the shallow, protected areas of the bay as a mating and nursery ground. Humpback whales were also recorded extensively during winter, in more offshore waters, with a significant number of mother-calf pairs sighted. Bryde’s whales were recorded in offshore waters during summer and autumn, where they were primarily observed travelling and foraging. Bottlenose dolphins were the most prolific species sighted. They were recorded year-round throughout the inshore waters of the bay, with large group sizes (up to 500 animals), and displayed a wide variety of behaviours. Humpback dolphins were observed in extremely shallow and inshore waters (mean bottom depth of 6.6 m) along the south-west corner of the bay, in small groups of approximately three individuals. Common dolphins were the least observed species, and were mainly observed foraging in large groups of up to 800 individuals. The results of this study indicate how cetaceans utilise the bay in significantly different ways. Geographical and anthropogenic factors have influenced the spatial and temporal distribution of these animals and have resulted in habitat preferences, as well as potential key habitats, in the bay. Thus, this study has provided baseline information for future research and for better informed conservation and management strategies in Algoa Bay.
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  • Date Issued: 2011

The ‘refeudalisation’ or the ‘return of the repressed’ of the public sphere?:

  • Authors: Garman, Anthea
  • Date: 2011
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/159857 , vital:40350 , DOI: 10.1080/02560054.2011.621293
  • Description: The prevalent depiction of the heyday of the public sphere and its fall from grace under present-day, publicity-ridden, highly commercialised media, with their individualised address of entertainment, is an inadequate conception of today's complex public spheres. The 18th-century bourgeois public sphere had a number of features – often repressed in practice and in theory – which were bound to have their outcomes and a/effects in the public spaces, practices and vehicles we experience today.
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  • Date Issued: 2011

Theiler’s murine encephalomyelitis virus infection induces a redistribution of heat shock proteins 70 and 90 in BHK-21 cells, and is inhibited by novobiocin and geldanamycin:

  • Authors: Mutsvunguma, Lorraine Z , Moetlhoa, Boitumelo , Edkins, Adrienne L , Luke, Garry A , Blatch, Gregory L , Knox, Caroline M
  • Date: 2011
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/165085 , vital:41207 , DOI: 10.1007/s12192-011-0262-x
  • Description: Theiler’s murine encephalomyelitis virus (TMEV) is a positive-sense RNA virus belonging to the Cardiovirus genus in the family Picornaviridae. In addition to other host cellular factors and pathways, picornaviruses utilise heat shock proteins (Hsps) to facilitate their propagation in cells. This study investigated the localisation of Hsps 70 and 90 in TMEV-infected BHK-21 cells by indirect immunofluorescence and confocal microscopy. The effect of Hsp90 inhibitors novobiocin (Nov) and geldanamycin (GA) on the development of cytopathic effect (CPE) induced by infection was also examined. Hsp90 staining was uniformly distributed in the cytoplasm of uninfected cells but was found concentrated in the perinuclear region during late infection where it overlapped with the signal for non-structural protein 2C within the viral replication complex.
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  • Date Issued: 2011

Thermal degradation of diamond compacts: a TEM investigation

  • Authors: Westraadt, Johan Ewald
  • Date: 2011
  • Subjects: Materials -- Thermal properties Chemical weathering
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10948/10829 , vital:26827
  • Description: Diamond compacts consist of fine diamond grains bonded together by using high pressure and high temperature. In this study transmission electron microscopy (TEM)was used to study thermal degradation of diamond compacts. Three different types of diamond compacts – namely cobalt polycrystalline diamond (PCD), calcium carbonate PCD, and diamond-SiC composites – were investigated with TEM to understand the processes that occur during synthesis. These compacts were then heated in inert atmospheres and the chemical changes studied with TEM. It was found that PCD, using cobalt as a bonding agent, will degrade after exposure to temperatures above 750ºC. The cobalt pools contain tungsten in solid solution. During heat treatment above 700ºC the solid solution tungsten combines with cobalt and dissolved carbon to form η-phase particles at the cobalt/diamond interface. At higher temperatures or insufficient tungsten levels the rate of dissolved carbon, into the cobalt pool, is too high and the excess carbon will form as graphite in the cobalt pool. Increased levels of solid solution tungsten, in the cobalt, is expected to delay the onset of graphitization in the diamond compact, thereby increasing the thermal stability of the diamond compact. Non-metallic PCD using calcium carbonate as a bonding agent was successfully sintered in this study. TEM revealed similar micro-structural features as in cobalt based PCD. No signs of thermal degradation were found after exposure to 1200ºC in vacuum for this PCD. Contaminants introduced during processing prevented a detailed study of the binder in this system. The effect of substitutional metal atoms and plastic deformation of diamond on the thermal stability of diamond-SiC composites were investigated. A piston cylinder press was developed and used to synthesize diamond-SiC composites with different levels of plastically deformed diamond. It was concluded that substitutional metal atoms and plastic deformation of diamond grains play no role in the thermal degradation of diamond compacts at 750ºC. The thermal degradation of cobalt PCD is therefore completely determined by the cobalt/diamond interaction at 750ºC.
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  • Date Issued: 2011

The design of a visitor education and research centre for Sutherland, Western Cape

  • Authors: Du Toit, David Jacob Johannes
  • Date: 2011
  • Subjects: Visitors' centers -- South Africa -- Western Cape -- Designs and plans Visitors' centers -- South Africa -- Western Cape
  • Language: English
  • Type: Thesis , Masters , MArch
  • Identifier: http://hdl.handle.net/10948/38934 , vital:35014
  • Description: The modern visitor centre evolved rapidly with the world wide growth in tourism and its significant contribution to local economies. This new building type has provided many new opportunities for architects to work on small to medium size building with a greater meaning attached to them. However, architects would now have to deal with the problems that tourists bring! How must architects incorporate local history, culture and memory? The visitor centre is the combination of the local tourism office and museum. This new type of building is a combination of those formerly distinct building types which had two separate and different functions. “gateway building” The contemporary visitor centre combines the distribution of tourist/visitor information with the interpretation of particular regions. This interpretation of cultural and natural history links the visitor centre to the local history museum, however whereas local history museums often struggle with expanding collections, limited resources and low visitation levels, visitor centres have been able to attract greater government funding. The media of interpretation also differs dramatically, with visitor’s centres often using multimedia technology to enliven cultural history or educational displays. However they can also suffer from static displays which having been viewed once, discourage repeat visits. What is a contemporary visitor centre? Figure 1: Guggenheim Museum, Bilbao. Showing centre as “icon” building. This interpretation role of visitor centres has resulted in them becoming a major focus for visitation. The must-see status of these buildings is often pursued through dramatic form. Briefs for visitor centres often demand an “icon” envisaging that the building will itself, become a marketable destination. Buildings that try and become destinations in themself often run the risk of not promoting the area or location but rather them self. Visitor centres can therefor contribute to the transformation of destinations in both positive and negative ways. They can either help with economic, environmental and cultural revival of regions or they can be involved in changing places and overshadowing the very features they are meant to enhance.
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  • Date Issued: 2011

Time series models for paired comparisons

  • Authors: Sjolander, Morne Rowan
  • Date: 2011
  • Subjects: Paired comparisons (Statistics)
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:10577 , http://hdl.handle.net/10948/d1012858
  • Description: The method of paired comparisons is seen as a technique used to rank a set of objects with respect to an abstract or immeasurable property. To do this, the objects get to be compared two at a time. The results are input into a model, resulting in numbers known as weights being assigned to the objects. The weights are then used to rank the objects. The method of paired comparisons was first used for psychometric investigations. Various other applications of the method are also present, for example economic applications, and applications in sports statistics. This study involves taking paired comparison models and making them time-dependent. Not much research has been done in this area. Three new time series models for paired comparisons are created. Simulations are done to support the evidence obtained, and theoretical as well as practical examples are given to illustrate the results and to verify the efficiency of the new models. A literature study is given on the method of paired comparisons, as well as on the areas in which we apply our models. Our first two time series models for paired comparisons are the Linear-Trend Bradley- Terry Model and the Sinusoidal Bradley-Terry Model. We use the maximum likelihood approach to solve these models. We test our models using exact and randomly simulated data for various time periods and various numbers of objects. We adapt the Linear-Trend Bradley-Terry Model and received our third time series model for paired comparisons, the Log Linear-Trend Bradley-Terry Model. The daily maximum and minimum temperatures were received for Port Elizabeth, Uitenhage and Coega for 2005 until 2009. To evaluate the performance of the Linear-Trend Bradley-Terry Model and the Sinusoidal Bradley-Terry Model on estimating missing temperature data, we artificially remove observations of temperature from Coega’s temperature dataset for 2006 until 2008, and use various forms of these models to estimate the missing data points. The exchange rates for 2005 until 2008 between the following currencies: the Rand, Dollar, Euro, Pound and Yen, were obtained and various forms of our Log Linear-Trend Bradley-Terry Model are used to forecast the exchange rate for one day ahead for each month in 2006 until 2008. One of the features of this study is that we apply our time series models for paired comparisons to areas which comprise non-standard paired comparisons; and we want to encourage the use of the method of paired comparisons in a broader sense than what it is traditionally used for. The results of this study can be used in various other areas, like for example, in sports statistics, to rank the strength of sports players and predict their future scores; in Physics, to calculate weather risks of electricity generation, particularly risks related to nuclear power plants, and so forth, as well as in many other areas. It is hoped that this research will open the door to much more research in combining time series analysis with the method of paired comparisons.
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  • Date Issued: 2011

Towards a critical understanding of media assistance for "new media" development

  • Authors: Mathurine, Jude
  • Date: 2011
  • Subjects: Mass media -- Technological innovations , Mass media -- Political aspects
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:3459 , http://hdl.handle.net/10962/d1002914 , Mass media -- Technological innovations , Mass media -- Political aspects
  • Description: The field of media assistance has grown ever more complex with the inclusion of ‘new media’ networks, channels, tools and practices (such as the Internet, satellite television, mobile devices, social media and citizen journalism) to the media development mix. Adding to the ferment is the increasing convergence between the formerly discrete terrains of ICT for development, media for development and (mass) media development. Much of the discussion regarding the utility and objectives of media development in general and ‘new media’ in particular has been viewed through a modernist and techno-determinist prism which offers a limited ideological view of media development and its objects and consequently, a limited set of communication approaches and strategies. This study contextualises the assumptions of media development historically and critically, with particular focus on new media’s roles and relationships with the media environment, and its objectives democratisation and development. Through the application of literature, theory and various research studies, this thesis establishes a broader view of new media’s role and diverse consequences for media development, democracy and development. The study recommends greater collaboration, contextual research and theorisation of media development and new media as part of mixed media systems and cognisant of the multi-dimensional natures of its objects of democracy and development. One implication is the need for professionalisation of the media development and media assistance sector. In relation to the influences of new media on media use and the media as an institution, it motivates the need to address digital divides and emphasise the sustainability of the practice of journalism.
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  • Date Issued: 2011

Towards a standard model for networked audio devices

  • Authors: Eales, Andrew , Foss, Richard
  • Date: 2011
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/427151 , vital:72418 , https://www.aes.org/e-lib/online/browse.cfm?elib=16144
  • Description: Different control protocols for networked audio devices typically emphasize particular aspects of a device, such as the representation of parameter data, or a representation of the functional structure of a device. A sophisticated device model must represent parameter data, device structure and the visual presentation of controls. Parameter data should be related to the device structure, while also being represented within a flexible, logical hierarchy. The development of a standard device model is proposed and discussed with reference to the OSC, IEC62379, ACN and X170 control protocols. This abstract model is independent of any specific control protocol, and provides support for interoperability between control protocols. The proposed model is also discussed within the context of an object-based approach to service enumeration and control using an associative, shared memory model.
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  • Date Issued: 2011

Towards a sustainable bioprocess for the remediation of acid mine drainage

  • Authors: Mambo, Mutsa Prudence
  • Date: 2011
  • Subjects: Acid mine drainage , Algae culture , Reduction (Chemistry) , Hydrolysis , ASPAM model (Acid mine drainage) , Water -- Purification
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5955 , http://hdl.handle.net/10962/d1006167 , Acid mine drainage , Algae culture , Reduction (Chemistry) , Hydrolysis , ASPAM model (Acid mine drainage) , Water -- Purification
  • Description: Acid mine drainage is of growing concern for both developing and developed economies. Thus there is increasing pressure to develop alternative remediation strategies. Biological sulphidogenic mechanisms have long since been studied but, very few have been implemented on a large scale. Limitations are due to the inability to acquire a suitable, low cost, environmentally friendly, renewable carbon source. The present study investigated the use of an algae biomass generated by the HRAOP of an IAPS as a carbon source for the EBRU 00AB/06 SRB consortium. The algae biomass and consortium were utilized together to remediate simulated AMD. Remediation involved decreasing the sulphate and metal concentrations in solution and decreasing the acidity of a simulated AMD. Experiments were carried out to investigate the capability of the EBRU 00AB/06 SRB consortium for sulphate reduction and sulphide generation. The consortium produced colonies when grown under anaerobic conditions in Petri dishes containing modified lactate SRB medium. The SRB consortium reduced the sulphate concentration of modified Postgates medium B and generated sulphide. Further analysis of the EBRU 00AB/06 SRB consortium revealed that the consortium was minimally impacted at pH 5 and by sulphate and iron at 3 g.L-1 and 0.5 g.L-1 respectively. The EBRU 00AB/06 SRB consortium was exposed to Actinomycin D and Ethidium Bromide to determine whether transcription and translation of proteins was required for sulphate reduction. Results indicated that sulphide generation and sulphate reduction were inducible. Analysis of the algae biomass used in this study revealed the empirical formula C1.0H1.91N0.084S0.003O0.36 indicating a carbon source rich in the nutrients required to sustain microbial development. Light microscopy revealed that algae cell walls and in particular those of Pediastrum were susceptible to acid hydrolysis. Dinitrosalicylic acid, Nile red, Bradford and Ninhydrin assays were used to determine the reducing sugar, lipid, protein and amino acid content respectively, of the mixed algae biomass. Results showed that upon exposure of the biomass to simulated AMD at pH 1 and pH 3, the concentration of reducing sugars and amino acids in solution increased. Whereas levels of lipids remained unchanged while the protein concentration decreased, indicating that, upon exposure of algae biomass to AMD, simulated or otherwise, cells ruptured, proteins were hydrolyzed and polysaccharides were broken down to sugars which are immediately available for SRB utilization. Exposure of biomass to simulated AMD revealed further that the presence of algae biomass increased the pH of simulated AMD (pH 3) to pH 7.67 after 4 d. Likewise, the pH of simulated AMD at 1 increased to 1.77 after 2 d while pH of the neutral control increased to 8.1 after 4 d. A direct comparison between lactate and algae biomass revealed 94 % sulphate removal after 23 d in the presence of algae biomass while 82 % sulphate removal was measured in the presence of lactate. Thus the EBRU 00AB/06 SRB consortium successfully utilized algae biomass for sulphate reduction and sulphide generation. In another experiment to establish if the consortium could remediate simulated AMD (pH 5) containing 0.5 g.L-1 iron and 3 g.L-1 sulphate while utilizing an algae biomass as the carbon source no residual iron was detected after 14 d and by day 23, an 89.07 % reduction in sulphate was measured. The results of this investigation are discussed in terms of utilizing a readily available and renewable biomass in the form of microalgae produced in HRAOPs as an effective carbon source in the SRB catalysed remediation of AMD.
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  • Date Issued: 2011

Towards community environmental education using current institutional resources, GIS and remote sensing, and local knowledge: a case of the Nandi Hills and Nandi Forests, Western Kenya

  • Authors: Tanui, Julius Gordon
  • Date: 2011
  • Subjects: Environmental education -- Kenya -- Western Province , Community-based conservation -- Kenya -- Western Province , Conservation of natural resources -- Kenya -- Western Province
  • Language: English
  • Type: Thesis , Doctoral , DPhil
  • Identifier: vital:9568 , http://hdl.handle.net/10948/d1016074
  • Description: The Nandi Hills and Nandi Forests in Nandi County, Kenya are major water catchments for Lake Victoria. However, these resources have faced significant decline and degradation in recent times, thereby impacting the hydrological quality and quantity in the Lake Victoria Basin. This study was informed by the observed degradation of the Nandi Hills and Nandi Forests, epitomized by the receding forest cover, drying up of previously permanent streams, instances of mudslides and rock falls, and downstream flooding. The study therefore sought to interrogate the current institutional environmental and educational arrangements and practices which are pertinent to the sustainable management of the Nandi Hills Forests, the perceptions and understandings of the local population in terms of forest resources and land use, and the information that can be provided by GIS and Remote Sensing data, in order to produce a heuristic for planning community environmental education in the Nandi County. To achieve this, a mixed methodological design which incorporated both qualitative and quantitative data was embraced. The mixed method approaches used in this study were the concurrent triangulation and nested/embedded designs. A four-tier analysis was carried out once all the data had been coded and grouped. The analysis covered three categories of the population in the study area; namely the households, institutions and community groups, and analysis of Landsat images for change detection. The study reveals that there are several state and non-state institutions that are involved in the management of the Nandi Hills Forests and that their efforts have seen an improvement in the perceptions of the local population in terms of the importance of environmental management of the forests. Analysis of the Landsat images has revealed receding natural forest cover. The contribution of informal, local and indigenous knowledge to sustainable management of the Nandi Hills Forest was notable (85 percent of the population attribute their knowledge on forests and forestry to informal knowledge sources). These results informed the development of a heuristic to enable the adoption of strategies using readily accessible, though loosely applicable, information for problem solving in developing and implementing community environmental education practices for effective forest management and conservation practices that are responsive to the needs of the Nandi Forest community.
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  • Date Issued: 2011

Towards monitoring that makes sense : action research design of a planning, learning and accountability system for a sustainable agriculture programme in Eastern Indonesia

  • Authors: Deprez, Stefan Gert Marie
  • Date: 2011
  • Subjects: Agricultural development projects -- Indonesia Agricultural administration -- Monitoring -- Indonesia Action research -- Case studies Action research in education
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1801 , http://hdl.handle.net/10962/d1003686
  • Description: This study is an account of an action research process to develop a planning, learning and accountability (PLA) system for the sustainable agriculture chain development programme of VECO (Vredeseilanden Country Office) Indonesia. Many monitoring and evaluation (M&E) processes in development programmes are largely carried out to provide information for funding agencies, to meet external accountability requirements and for symbolic protection. This study generates insights into an integrated, learning-oriented monitoring practice which fosters reflective practice, provides feedback to programme stakeholders about performance, progress and results achieved, facilitates improved accountability, and generates information and knowledge useful for the programme stakeholders to take decisions for improved action. It is argued that M&E systems have the potential, if developed well, to serve as a framework or ‘carrier’ for organisational and institutional learning – an essential requirement to respond to the complex nature of development processes. Outcome mapping is presented as a possible approach to be used as the basis for such a M&E system. This study was underpinned by a socially critical orientation to development (programmes) and by an action research method to guide the PLA system design process. The design process was organized around seven steps - which in themselves were a result of the action research process – including specific steps to ensure a learning-oriented M&E system. Based on the agreed purposes and intended uses of the monitoring and learning process, the resulting PLA system is focused around the organizational spaces and rhythms of VECO Indonesia which are central to sharing, debate, learning and decision-making. In this way, the PLA system becomes integral to the thinking and doing of the organization. It is built on the premise that monitoring does not end with gathering data; it also needs to include a process of understanding and deciding how data can best be used and analysed to strengthen concerted action and facilitate decision-making. It highlights the importance of sense-making – interpreting information to make it usable for action. Furthermore, it incorporates an approach to assess and consciously plan for the creation of the necessary organisational conditions to implement and maintain a learning-oriented M&E system. The study is completed by critical reflection on the relevance of VECO’s new PLA system for planning, learning and accountability, combined with the use of a future scenario technique to generate recommendations and identify critical future directions. Further exploration of ‘intelligent’ information-seeking methods and processes is called for; and a practice which moves beyond intra-organisational monitoring – focusing on VECO’s own monitoring needs – towards a monitoring process that facilitates change based on the viewpoints of, and in collaboration with local actors, i.e., institutional monitoring and learning, is recommended. VECO is encouraged to continue developing a mindset and practice whereby the programme team and partners have the ability to leave the safe zone of pre-determined outcomes and actions, and to make sense of the world as they engage in action.
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  • Date Issued: 2011

Towards the two-way symmetrical communication model: the use of social media to create dialogue around brands

  • Authors: Matthee, Christelle
  • Date: 2011
  • Subjects: Social media , Public relations
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:8385 , http://hdl.handle.net/10948/1370 , Social media , Public relations
  • Description: Social media has radically altered today's media landscape, and presents public relations practitioners with new possibilities and opportunities to promote their companies. Social media enables public relations to observe in order to find out what people need; what content they are looking for; and how your company can help them. However, will engaging in online conversations give an organisation‘s consumers a voice? Past PR models illustrate how methods of communication was established and used in the past. However, the Grunig and Hunt two-way symmetrical model creates the possibility of two-way communication (dialogue) between consumer and organisation in which the power relations are equal. By applying Web 2.0 (social media) to these models, one can explore new ways of two-way communication. Finally by applying these elements to each other, a case study can be created to prove if social media can be used to create a dialogue between consumer and organization.
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  • Date Issued: 2011

Traditional, complementary and alternative medicine use in HIV-positive patients

  • Authors: Lunat, Imran
  • Date: 2011
  • Subjects: HIV infections -- Alternative treatment -- South Africa -- Nelson Mandela Metropolitan Municipality
  • Language: English
  • Type: Thesis , Masters , MPharm
  • Identifier: vital:10137 , http://hdl.handle.net/10948/1388 , HIV infections -- Alternative treatment -- South Africa -- Nelson Mandela Metropolitan Municipality
  • Description: The standard anti-retroviral drugs (ARVs) used for the treatment of HIV/AIDS have significant side effects resulting in a lack of adherence and the emergence of multidrug resistant viral strains. These drugs are also expensive, making it essential to investigate all alternatives to classical HIV/AIDS treatment. A wide variety of nonconventional medicines are used by patients for the treatment HIV and for symptoms associated with HIV. So long as they are safe and effective, traditional, complementary and alternative medicines (TCAMs) may be considered more advantageous for developing countries as they are relatively cheap, more accessible and widely accepted by local populations. The aim of this study was to determine the prevalence of TCAM use in HIV-positive patients, prior to, and during ARV therapy. The study was exploratory, cross sectional and observational in nature. Participants were selected via convenience sampling from the Nelson Mandela Bay Municipality, and included 244 HIV-positive patients, 29 health care professionals (HCPs) and 30 traditional, complementary and alternative practitioners (TCAMPs). A wide variety of TCAMs were used by the sample population. These medicines were more commonly used by non-ARV patients (36 percent) compared with ARV patients (22 percent). A significant statistical difference in TCAM use between the ARV and non- ARV population was found in relation to education, employment, period of status awareness, patient opinion of personal health and the reasons for TCAM use. Amongst the HCPs, 24 percent recommended TCAM use prior to ARVs, and 55 percent were aware of patients self-prescribing before and during ARV treatment. Amongst the TCAMPs, 90 percent provided a wide range of TCAMs for HIV, with some giving consideration to conventional management. TCAMs are commonly used by HIV-positive patients on ARVs, as well as by those not on ARVs. These medicines are also the preferred form of treatment for those not seeking conventional treatment. TCAMs are widely available and recommended by TCAMPs as well as some HCPs. Due to public health concerns, clinical trials of the widely used TCAMs are crucial in order to establish the safety and efficacy of these medicines in HIV.
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  • Date Issued: 2011

Trials and triumphs in public office: the life and work of E J N Mabuza

  • Authors: Sarimana, Ashley
  • Date: 2011
  • Subjects: Mabuza, E J (Enos John), 1939- Public officers -- South Africa South Africa -- Politics and government -- 20th century South Africa -- History -- 20th century South Africa -- Social conditions -- 20th century Homelands (South Africa) -- Politics and government -- 20th century Homelands (South Africa) -- History -- 20th century Homelands (South Africa) -- Social conditions -- 20th century Apartheid -- South Africa South Africa -- Race relations Actor-network theory
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:3305 , http://hdl.handle.net/10962/d1003093
  • Description: Enos John Nganani Mabuza's life and work is used as a case study to highlight the conceptual and methodological theories and challenges in academic biographical writing regarding history, memory and legacies. This thesis answers the question: Who was Mabuza and what is his place or relevance in South Africa's history? We over-simplify and stereotype people because it is convenient. We judge others but there is no saint without a past or a sinner without a future. Mabuza reconciled with the main liberation movements and moved from a maligned position on the political fringes to a respectable one within the emerging black economic elite. History, like reference systems and values is not calcified or static. It is prone to interpretation, adaptation, modification, invention, manipulation, decomposition and re-composition. Bourdieu's habitus-field analysis, theory or logic of practice, notions of capital (symbolic, political, social, cultural and economic) is used together with Latour's actor-network theory as the basis of analysis of the social contracts and trust bonds that Mabuza was able to create and which enabled him to navigate South Africa's socio-political and economic milieus during apartheid and the transition in the early 1990s. As people or actors, we believe in the mantra, nothing ventured, nothing gained. We exercise agency and take risks every day. We make choices and those choices have consequences. Mabuza's choices in the fields of education, politics and business had implications for how he is perceived or has been written into history. His choices put notions of identity, citizenship, power, legitimacy, ambition, elite accommodation, class, personal and professional networks, popular struggles, agency and structure under the spotlight. Mabuza's involvement in Bantustan politics, for instance, is contextualised in terms of a historical overview of the unpopular role played by traditional authorities in South Africa before and during colonialism and apartheid. His later foray into the world of business, however, was facilitated in part, by the personal and professional contacts that he made whilst he was in politics and the opportunities which opened up during the country's political transition. Mabuza adapted to changing circumstances and demonstrated a level of versatility which other Bantustan functionaries did not or could not exercise.
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  • Date Issued: 2011

Triggers and barriers to youth entrepreneurship in the Eastern Cape South Africa

  • Authors: Chindoga, Lynety
  • Date: 2011
  • Subjects: Youth development -- South Africa , Entrepreneurship -- South Africa -- Eastern Cape , Young adults -- Employment -- South Africa
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10353/25948 , vital:64636
  • Description: To realise the dream of the African Renaissance and a better life for all South Africans, the entrepreneurial energies of all people, including children, should be harnessed to contribute towards economic development, job creation and poverty alleviation. Entrepreneurship creates wealth and results in economic prosperity for a country. However, in South Africa, entrepreneurship still remains a dream yet to be realised. This is supported by the findings of Maas and Herrington (2006), who identified entrepreneurial activity in South Africa to be very weak as evidenced by a low Total Entrepreneurial Activity (TEA) rate. Youths are not engaging in entrepreneurial activity and are making the bulk of the unemployed in South Africa. The primary objective of this study was to investigate the perceived triggers and barriers to youth entrepreneurship in South Africa. Two sets of questionnaires were self- administered to high school students and university students. The respondents which consisted of three hundred and twenty three university students and two hundred and fifty six high school students, were selected using simple random sampling method. Five point Likert scale was used to measure the responses. Descriptive as well as inferential statistics were used to analyse the data. The results indicated that youth entrepreneurial intention is low in South Africa. The results also indicated that students perceived mainly extrinsic rewards, market opportunities as well as intrinsic rewards as the three top triggers towards entrepreneurial intention. Independence/autonomy and capital were also regarded as triggers to entrepreneurial intentions. The barriers to youth entrepreneurship included lack of capital, skill and support as well as lack of market opportunities and risk. The study recommends that in order to encourage youth entrepreneurial intentions, government and all stakeholders should ensure that all the perceived triggers are made available. In addition, the barriers to youth entrepreneurship should be minimised. , Thesis (MCom) -- Faculty of Management and Commerce, 2011
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  • Date Issued: 2011

Trophic ecology of zooplankton at a frontal transition zone: fatty acid signatures at the subtropical convergence, Southern Ocean

  • Authors: Richoux, Nicole B
  • Date: 2011
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/458033 , vital:75711 , xlink:href="https://doi.org/10.1093/plankt/fbq132"
  • Description: Regional variations in fatty acid composition were assessed in zooplankton communities situated immediately north and south of the subtropical convergence (STC), where warm (maximum 21°C) nutrient-poor waters of the southwest Indian Ocean converge with cool (minimum 11°C) nutrient-rich subantarctic waters of the Southern Ocean. I hypothesized that food web structures differ from north to south based on average spatial differences in primary productivity, and that zooplankton in the more productive region show enhanced herbivorous feeding. Several taxonomic groups including euphausiids showed differences in their fatty acid signatures from north to south, indicating the existence of measurable within- and among-species differences in trophic relationships between the two communities, presumably stemming from variations in food quality and availability. The indices 22:6ω3/20:5ω3, 18:1ω9/18:1ω7 and Σω3/Σω6 indicated that carnivory was the dominant feeding mode in the north, whereas herbivory was more prevalent in the south, a pattern that was not detected in the same region using stable isotope ratios. Such conflicting results substantiate the importance of utilizing more than one method to investigate feeding relationships in aquatic systems. Fatty acid profiles of the amphipod Themisto gaudichaudii revealed some distinct herbivory markers, indicating more complex feeding habits by this important pelagic species than previously reported. My findings shed new light on the regional variations in zooplankton diet and food web dynamics in a poorly understood but critically important frontal zone bordering the Southern Ocean.
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  • Date Issued: 2011

Trophodynamics of the benthic and hyperbenthic communities inhabiting the Sub-Antarctic Prince Edward Islands : stable isotope and fatty acid signatures

  • Authors: Allan, Elizabeth Louise
  • Date: 2011
  • Subjects: Benthos -- Prince Edward Islands Benthos -- Feeding and feeds -- Prince Edward Islands Benthos -- Nutrition -- Prince Edward Islands Prince Edward Islands
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:5806 , http://hdl.handle.net/10962/d1006350
  • Description: The aim of this study was to investigate spatial changes in the trophic and energy pathways of the benthic community in the shallow shelf waters of the sub-Antarctic Prince Edward Islands (PEI). A combination of stable isotope and fatty acid analyses were used to provide a time-integrated view of the assimilated feeding history of selected components of the PEI benthic community. This study forms part of the larger project entitled “Variability in the Southern Ocean ecosystems” and is a contribution to the South African National Antarctic Programme (SANAP). During austral autumn 2009, benthic specimens were collected from 10 stations (from depths of 70 to 295 m) in different regions around the PEI: inter-island shelf (upstream, between and downstream of the islands) and nearshore. Historical data were combined with new data collected during 2009 to assess the long-term trends in the feeding ecology of the benthos in the region of the islands. The stable isotope and fatty acid signatures of the benthic suspension- and deposit-feeding organisms generated during this study suggested that these two communities incorporated both phytoplankton and kelp in their diets. Stable isotope, and to a lesser extent fatty acid signatures, indicated that kelp contributed more to the diets of those organisms in close proximity to the kelp beds (nearshore stations) than those from the inter-island region. Overall, however, pelagic phytoplankton was the dominant food source in the diets of all organisms, even for those living near the kelp beds. Notable exceptions were the sponges and bryozoans, in which kelp and phytoplankton contributed similar proportions to their diets, most likely resulting from a size restricted feeding mode. There were, therefore, no distinct spatial differences in the importance of the various food sources. However, fatty acid compositional data indicated increased food quality between and within the lee of the islands compared to upstream. The organisms collected upstream of the PEI had substantially lower quantities of total fatty acids (TFAs) than organisms of the same species collected from nearshore, open shelf or downstream stations. The increased food quality between and within the lee of the islands was likely a result of the “island mass effect”, which reflects increased phytoplankton concentrations at the PEI. The fatty acid profiles of hyperbenthic shrimp Nauticaris marionis, a key species in the PEI ecosystem, revealed no distinct ontogenetic or spatial patterns. This result is in contrast to the stable isotope analyses, which detected both spatial and ontogenetic differences in the diet of the shrimp. Nearshore shrimp were more ₁₃C-enriched than those from the inter-island region, suggesting increased kelp entering the food web within these regions. In addition, the shrimps demonstrated enrichment in δ₁₃C and δ₁₅N signatures with an increase in size, resulting in a relatively distinct separation of size classes, thus reflecting niche separation through their diets. The fatty acid profiles revealed that the shrimp all contained large proportions of polyunsaturated fatty acids (PUFAs) and essential fatty acids (EFAs), indicating that the quality of food consumed was similar among size class and region despite the niche separation and variation in carbon sources utilised. In addition, diatom and dinoflagellate fatty acids (20:5ω3 and 22:6ω3, respectively) occurred in the highest proportions in N. marionis, highlighting the importance of phytoplankton (indirectly) in their diet. These results represent strong evidence that phytoplankton is an importance food source in the PEI ecosystem. The temporal investigation of isotope signatures in the benthos at the PEI indicated that N. marionis demonstrated an overall depletion in δ₁₃C signatures over the period of 1984 to 2009 (nearshore: -2.55 ‰, inter-island: -2.32 ‰). Overall, the benthic community showed similar depletions in δ13C signatures (from -1.96 to -4.70 ‰), suggesting that shifts have occurred in the carbon signatures at the base of the food web. The depletion in δ₁₃C signatures of the benthos at the PEI most likely reflects increased contributions of smaller slow growing phytoplankton cells (more depleted signatures than large fast growing cells) in the diets of these organisms over time. These diet shifts, in turn, suggest a decrease in productivity has occurred at the islands, likely due to a decreased frequency and intensity of the “island mass effect”. Decreased phytoplankton productivity at the PEI likely results from the southward shift in the average position of the sub-Antarctic Front (SAF), most likely in response to climate change, which in turn promotes flow-through conditions rather than retention at the PEI.
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  • Date Issued: 2011

Trust building strategies to enhance collective bargaining processes in organisations

  • Authors: Ngalo, Osmond Tolo
  • Date: 2011
  • Subjects: Trust , Collective bargaining
  • Language: English
  • Type: Thesis , Doctoral , DTech
  • Identifier: vital:9398 , http://hdl.handle.net/10948/1312 , Trust , Collective bargaining
  • Description: The main research problem in this study was to identify what trust-building strategies can be utilised by organisations to enhance collective bargaining processes. To achieve this objective a theoretical Institutional Arrangements-Based Model of trust-building was conceptualised, developed and presented in Chapter 5. The presentation of this model was the culmination of the research design phases outlined below: -The first phase consisted of a literature survey undertaken to discover the nature and dynamics of the concept "trust". -The second phase consisted of surveying the literature attempting to understand the nature of the collective bargaining process, its elements and types and the environmental factors that tend to impinge on it. -The final phase of the literature survey focused on various trust-building strategies, theories and models that can be utilised by organisations to ii enhance collective bargaining processes. Trust is generally acknowledged as a necessary requirement for effective and successful workplace relationships. Because of this factor it is crucial that South African employer-employee relationships are improved in a conscious and sustainable way in order for our businesses to remain competitive in the face of global competition. With this reality in mind there is still much in the South African labour relations environment that fosters conflict. One of the primary factors that impinge on trust in employer-employee relations in South Africa is the previous government‘s divisive and racist apartheid policies. These policies have resulted in serious structural imbalances in the economy, the skewed distribution of wealth and the general scarcity of resources to address these attendant challenges. Finnemore and van Rensburg (2002, p. 36) surveys the current labour relations scenario and comments about the extent to which it has been severely affected by apartheid. Some of its appalling outcomes are: racial divisions between skilled and unskilled workers, apartheid wage gaps, poorly educated workers, dictatorial management styles and a lack of protection for the most vulnerable workers. As revealed in this research study there are still widely divergent views at the workplace regarding the nature and levels of trust that are prevalent. The overwhelming view, however, is that there is, generally, a lack of trust between managerial and employee collective bargaining teams. This lack of trust which is evident between employer and employee parties will tend to result in collective bargaining processes being embarked upon in a climate imbued with the negative spirit of distrust. The recommended Institutional Arrangements-Based Model of trust-building advocates for a process of trust-building prior to any collective bargaining initiatives. This process, as depicted in the elements of the recommended model, needs to begin with phases which will focus on frame-alignment and the identification of all sources of distrust between the parties. These prescribed sessions seek to culminate in a common understanding, between the contesting parties, of their real divergent issues and concerns as well as their existing commonalities. The next phases of the recommended model entail the parties, jointly, developing proposals and policies that in the short and long term will aim at the resolution of the identified sources of distrust and thereby reduce the psychological distance between them. The final phase of the model entails the implementation of joint problem–solving resolutions and the development of appropriate policies i.e. institutional arrangements, to deal with all conflict-prone areas of the business operations. Simultaneously, there needs to be continuous evaluation and monitoring of organisational trust and the "agreed to" trust-building strategies to ensure that distrust is reduced or eliminated in the long term, allowing the organisation and the individual employees to perform at their optimum in order to achieve their common goals.
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  • Date Issued: 2011

Unitarity constraints on the ratio of shear viscosity to entropy density in higher derivative gravity

  • Authors: Brustein, Ram , Medved, Allan J M
  • Date: 2011
  • Language: English
  • Type: text , Article
  • Identifier: vital:6815 , http://hdl.handle.net/10962/d1004325
  • Description: We discuss corrections to the ratio of shear viscosity to entropy density η/s in higher-derivative gravity theories. Generically, these theories contain ghost modes with Planck-scale masses. Motivated by general considerations about unitarity, we propose new boundary conditions for the equations of motion of the graviton perturbations that force the amplitude of the ghosts modes to vanish. We analyze explicitly four-derivative perturbative corrections to Einstein gravity which generically lead to four-derivative equations of motion, compare our choice of boundary conditions to previous proposals and show that, with our new prescription, the ratio η/s remains at the Einstein-gravity value of 1/4π to leading order in the corrections. It is argued that, when the new boundary conditions are imposed on six and higher-derivative equations of motion, η/s can only increase from the Einstein-gravity value. We also recall some general arguments that support the validity of our results to all orders in the strength of the corrections to Einstein gravity. We then discuss the particular case of Gauss-Bonnet gravity, for which the equations of motion are only of two-derivative order and the value of η/s can decrease below 1/4π when treated in a nonperturbative way. Our findings provide further evidence for the validity of the KSS bound for theories that can be viewed as perturbative corrections to Einstein gravity.
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  • Date Issued: 2011
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