Rebellious uniform
- Authors: Farmer, Mark Ross
- Date: 2012
- Subjects: High school students -- South Africa -- Eastern Cape -- Discipline Teenagers -- South Africa -- Eastern Cape -- Conduct of life Teenagers -- Education (Secondary) -- South Africa School discipline
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: vital:2401 , http://hdl.handle.net/10962/d1002197
- Description: In this thesis, I focus on adolescent teens at Kingswood College High School, where I am currently employed as a student assistant in Grahamstown. I form part of a networked hierarchy at Kingswood College whereby I am expected to perform duties which require me to uphold discipline, forge respect and act as a mentor to students. Within this complex role I am mindful of the power dynamics within the school and my focus is on how the students at Kingswood College in some instances challenge them. Regulations in regard to uniforms and in regard to the arrangement of each learner’s belongings insist on the sublimation/sacrificing of an individual identity in favour of an institutional one. Thus tiny departures from those norms, slight transgressions, might be understood as small rebellions which the boarder stages against disciplinary structures and the conformity demanded of him or her. I am particularly interested in these transgressions. In this thesis I attempt to unravel the complexities associated with such idiosyncrasies and how they play out amongst adolescent teens.
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Research and development of a preliminary South African voluntary carbon standard for landscape restoration projects
- Authors: Curran, Patrick
- Date: 2012
- Subjects: Carbon -- Environmental aspects -- Research -- South Africa , Carbon -- Standards -- Research , Restoration ecology -- Research -- South Africa , Environmental sciences -- Research
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4748 , http://hdl.handle.net/10962/d1006968 , Carbon -- Environmental aspects -- Research -- South Africa , Carbon -- Standards -- Research , Restoration ecology -- Research -- South Africa , Environmental sciences -- Research
- Description: The mandatory and voluntary carbon markets have both developed around the increasing trade of carbon offsets. In order to add legitimacy to an otherwise intangible commodity there has been a rise in the development of third party carbon certification standards, particularly in the voluntary market. These standards aim to provide independent, third party certification to projects that are developed specifically to generate and sell carbon offsets. South Africa has the opportunity to engage with these markets, but current participation in and certification of projects is sluggish. These projects have not taken off mainly due to the high transaction costs and lag times surrounding the current certification of projects', complex baseline methodologies, accounting uncertainty and the often bureaucratic systems surrounding the current voluntary carbon certification standards and methodologies. In order to overcome these pitfalls this project aimed to address these challenges through initiating the development of a preliminary South African voluntary carbon standard. This was done by: a) undertaking a critical assessment of the development of current carbon markets, with a particular focus on voluntary markets and third party certification, b) critically analysing the current voluntary carbon certification standards for best practices, pitfalls and weaknesses. To provide a better understanding of the historical development of voluntary certification standards, various established certification standards were evaluated, including the Forestry Stewardship Council (FSC), Marine Stewardship Council (MSC) and ISO 14000 standards. This analysis focussed on the challenges they faced in acceptance and in particular how they have managed to operationalize sustainable development within the certification process. In order to explicitly ensure the incorporation of a sustainable development assessment of projects under the proposed standard, an expert workshop was held with 14 experts from a wide variety of disciplines. These experts identified the crucial sustainable development challenges facing South Africa. They identified 12 sub-themes and 44 indicators that could be used to measure and incorporate sustainable development indicators into the certification process. These were then further developed through using the 'Input – Output – Outcome – Impact' framework model which allowed the indicators to be organised and understood and thus practical. The analysis of the voluntary certification standards and the development of the sustainable development indicator framework were ultimately incorporated into the development of the proposed South African voluntary carbon standard. The key approach to this standard is the incorporation and focus of the proposed standard to ensuring the generation of net SD benefits and placing them at the same level as carbon within the project design and development, validation and verification process. The full and effective integration of these has been missing within current fully fledged voluntary carbon standards, as they often rely on a mixture of project design standards to achieve this. Offering the inclusion of all components into one standard, specifically designed for South Africa, will not only assure SD credentials but also increase transparency and understanding, and reduce costs. This thesis allowed for the development of innovative new ideas and process focussed specifically at including and mainstreaming South Africa’s developmental challenges into the certification process. This is the hoped that the standard will effectively certify South African based landscape restoration projects, but also decrease costs and increase efficiencies in order to encourage the development of these projects. This preliminary standard not only aims to incorporate and address all the issues identified but also has the end goal of acting as the basis for future debate and development surrounding a potential South African voluntary carbon certification standard.
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Ritualised discourse practices of feedback in a university foundation programme: a critical investigation
- Authors: Richardson, Amy
- Date: 2012
- Subjects: Uncatalogued
- Language: English
- Type: thesis , text , Masters , MA
- Identifier: http://hdl.handle.net/10962/164955 , vital:41187
- Description: In order for students to become true members of academic communities of practice they need epistemological access, including guidance on central institutional knowledge-producing processes and mastery of key academic literacy practices. A powerful source of guidance is marker feedback. Drawing on key insights from the New Literacy Studies and taking up the mandate of Critical Ethnography to improve the status quo, this thesis reports on the feedback practices in a university foundation programme. The findings are based on three micro-case studies compiled and analysed by means of methods drawn from Ethnography, Sociolinguistics and Critical Analysis in conjunction with an expanded, multimodal, APPRAISAL analysis, including adjusted categories and the author’s own feedback typologies. Two major arguments emerge: the feedback provided amounts to a set of ritualised discourse practices and its effects can be likened to the product of the children’s game of Head-body-tail. Consequently, feedback conventions are opaque and, potentially, impede epistemological access. They further entrench five sets of ideologies: (1) Students must master basic English literacy before they are coached in more complex issues such as argumentation; an assumption which leads to differential socialisation. (2) There is a single set of literacy practices that is rewarded. (3) Students have different levels of authorial authority depending on their language abilities. (4) ‘Middle students’ may benefit the most from feedback. (5) Specific comments are preferred over general ones. Analysis of feedback, furthermore, shows that markers’ frames of reference shape their pedagogy and that draft and final versions of work may be framed differently by markers. These findings require a response and, in order to facilitate epistemological access, suggestions are made for improved marker training based on the problematisation of the ritual involved in marking students’ work in this university foundation programme. , Thesis (MA)--Rhodes University, Faculty of Humanities, Linguistics, 2012
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Rivers as borders, dividing or uniting? : the effect of topography and implications for catchment management in South Africa
- Authors: Smedley, David Alan
- Date: 2012
- Subjects: Rivers -- South Africa , Water-supply -- Management -- South Africa , Water-supply -- Management -- Orange River Watershed , Watershed management -- South Africa , Watershed management -- Orange River Watershed , South Africa -- Boundaries , Water-supply -- Management -- Citizen participation , Water-supply -- Government policy -- South Africa , Water-supply -- Political aspects -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4851 , http://hdl.handle.net/10962/d1005527 , Rivers -- South Africa , Water-supply -- Management -- South Africa , Water-supply -- Management -- Orange River Watershed , Watershed management -- South Africa , Watershed management -- Orange River Watershed , South Africa -- Boundaries , Water-supply -- Management -- Citizen participation , Water-supply -- Government policy -- South Africa , Water-supply -- Political aspects -- South Africa
- Description: South Africa's water resources are unequally distributed over space and time to a high degree and our already stressed water resources situation will only be exacerbated by climate change if current predictions are correct. The potential for conflict over increasingly strained water resources in South Africa is thus very real. In order to deal with these complex problems national legislation is demanding that water resource management be decentralized to the local level where active participation can take place in an integrated manner in accordance with the principles of IWRM. However, administrative and political boundaries rarely match those of catchments as, throughout South Africa, rivers have been employed extensively to delineate administrative and political boundaries at a number of spatial scales. The aim of this research is to determine if rivers act as dividing or uniting features in a socio-political landscape and whether topography will influence their role in this context. By considering sections of the Orange-Senqu River, some of which are employed as political or administrative boundaries, this project furthermore aims to consider the implications of this for catchment management in South Africa. South Africa's proposed form of decentralized water management will have to contend with the effects of different topographies on the way in which rivers are perceived and utilized. The ability of a river to act as a dividing or uniting feature is dependent on a number of interrelated factors, the effects of which are either reduced or enhanced by the topography surrounding the river. Factors such as the state of the resource, levels of utilization, local histories and the employment of the river as a political or administrative border are all factors that determine the extent to which a river unites or divides the communities along its banks, and are all influenced by topography. The implications of this for the management of catchments in South Africa are significant. Local water management institutions will have to contend with a mismatch in borders and in many cases bridge social divides that are deeply entrenched along the banks of rivers. Importantly, the need for a context specific approach to catchment management is highlighted.
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Ruth First in Mozambique: portrait of a scholar
- Authors: Tebello, Letsekha
- Date: 2012
- Subjects: First, Ruth, 1925-1982 Universidade Eduardo Mondlane Women political activists -- South Africa Journalists -- South Africa Anti-apartheid movements -- South Africa Government, Resistance to -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3320 , http://hdl.handle.net/10962/d1003108
- Description: Ruth First was an activist, journalist and sociologist trained by experience and credentialed by her numerous publications. Having lived most of her adult life as an intellectual and activist, First died in August 1982 at the hands of a regime and its supporters who intensely detested all these pursuits. This research project sketches the intellectual contributions made by the South African sociologist during her time at the Centre of African Studies at Eduardo Mondlane University, Mozambique. Her life like the newspaper she edited in the early 1970s was a Fighting Talk and this research project is about celebrating that life and valorising some of the life’s work that she left behind. Making use of qualitative research methods such as archiving, semi-structured interviews and contents analysis, this thesis sought to document Ruth First’s intellectual interventions while at the Centre of African Studies. Engaging with her work while she was in Mozambique and inserting her intellectual contributions, which like those of many African scholars have given way to debates from the global North, into our curriculum would perhaps be the real refutation of the assassin's bomb. This engagement is also crucial as it extends much further than the striking accolades which take the form of buildings and lectures established in her honour.
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Silence, like breathing
- Authors: van der Nest, Megan
- Date: 2012
- Subjects: South African poetry (English) -- 21st century , Creative writing (Higher education) , Diaries -- Authorship , English language -- Writing
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:5980 , http://hdl.handle.net/10962/d1015246
- Description: In this collection of free verse lyric poems I have drawn inspiration from childhood memories, as well as from the natural world and encounters with the people around me. Each poem focuses on a small moment, presenting an emotive portrait of a memory or an experience. These small moments lead, cumulatively, to deeper insights into myself and the world around me. The collection is divided into four seasons, in part because the work is strongly influenced by the natural world, but also because the progression of the seasons mirrors something of the personal journey reflected in the poems.
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Small mammal communities at high altitude within the Sneeuberg Mountain complex, Eastern Cape Province, South Africa
- Authors: Kok, Armand du Preez
- Date: 2012
- Subjects: Mountain animals -- Research -- South Africa -- Eastern Cape , Mammal populations -- Research -- South Africa -- Eastern Cape , Mammals -- Research -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5766 , http://hdl.handle.net/10962/d1005454 , Mountain animals -- Research -- South Africa -- Eastern Cape , Mammal populations -- Research -- South Africa -- Eastern Cape , Mammals -- Research -- South Africa -- Eastern Cape
- Description: Due to their widespread and specious nature, small mammals are ideal for biogeographical studies. Small mammals also effectively connect various trophic levels by being both consumers and prey items for other animals. The Great Escarpment is the dominant mountain landscape in South Africa. Yet, very little small mammal research has been conducted on the Great Escarpment outside of the Main Drakensberg Mountains. This is surprising given the importance of mountains in shaping regional ecology. In this study, I assessed the diversity and community composition of small mammals at three high altitude (>1700m) sites within the Sneeuberg Mountain Complex (SMC) from June 2009 to May 2010. I also tested the effectiveness of five different bait types for measuring small mammal diversity (i.e. number of individuals caught, species richness, Shannon diversity index and Simpson index of diversity). Out of a total of 423 captures, 292 individuals of 12 small mammal species (one shrew, one elephant shrew and 10 rodents) were recorded over 5280 trap nights. The species richness and diversity of small mammals captured at the three sites were similar and this homogeneity was probably related to the regional processes (e.g. climate and latitude) that govern species richness and diversity. The most effective bait type in terms of capture success, species richness and diversity measurements was peanut butter and oats. In addition, the use of richness estimators revealed that peanut butter and oats was the most effective bait for sampling the species richness of small mammals. The effectiveness of peanut butter and oats was related to this bait having a more attractive scent, when compared to the other bait types. Future studies should focus on researching the range of local and regional processes that drive small mammal diversity at high altitudes in South Africa. I also recommend the use of more than one bait type when planning to survey small mammal communities.
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Smashing the crystal ball: post-structural insights associated with contemporary anarchism and the revision of blueprint utopianism
- Authors: Alexander, Tarryn Linda
- Date: 2012
- Subjects: Social change , Utopian socialism -- Philosophy , Utopias -- Philosophy , Anarchism
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3311 , http://hdl.handle.net/10962/d1003099 , Social change , Utopian socialism -- Philosophy , Utopias -- Philosophy , Anarchism
- Description: This thesis is an exploration of the images which define revolution's meaning. It suggests a possible shifting of emphasis from the scientific imaginary which centres on identifying the correct way to totalising revolution, towards a post-structuralist-anarchistic imaginary which privileges prefigurative radicalisations of social relations in the here and now. It looks specifically at how the field of post-structuralism intertwines with historically anarchist concepts to generate an horizon of social change animated by experimental and open-ended transformations. While the thesis offers positive characterisations of the types of contemporary movements, tactics and principles which embody the change from closed to open utopianism, it is chiefly a commentary on the role of theory in depicting the complexity of relations on the ground and the danger of proposing one totalising pathway from one state of society to another. It asks the reader to consider, given the achievements of movements and given the insights of post-structuralism, whether it is still worthwhile to proclaim certainty when sketching the possibilities for transcendence toward emancipation, an aim, which in itself, is always under construction. I engage this by firstly establishing a practical foundation for the critique of endpoints in theory by exploring the horizontal and prefigurative nature of a few autonomous movements today. Secondly I propose the contemporary theory of post-structuralist anarchism as concomitant with conclusions about transformation made in the first chapter. Finally I recommend a few initial concepts to start debate about the way forward from old objectivist models of transformation. The uncertainties of daily life, crumbling of economic powers and rapid pace of change in the twenty-first century have opened up fantastic spaces for innovative thought. Reconsidering old consensus around what constitutes a desirable image of revolution is of considerable importance given today's burgeoning bottom-up political energy and the global debate surrounding the possibilities for bottom-up revolutionisation of society. I submit that theories which portray stories of permanent, pure and natural end-points to revolution are deficient justifications for radical action.
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Social capital and fisheries co-management in South Africa: the East Coast Rock Lobster Fishery in Tshani Mankozi, Wild Coast, Eastern Cape
- Authors: Kaminsky, Alexander
- Date: 2012
- Subjects: Social capital (Sociology) -- Economic aspects Human capital -- South Africa Fishery management -- South Africa Natural resources -- Co-management -- South Africa Rural poor -- South Africa Sustainable development -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3322 , http://hdl.handle.net/10962/d1003110
- Description: It is evident that natural fish stocks are in rapid decline and that millions of people around the world rely on these resources for food and for securing a livelihood. This has brought many social scientists, biologists and fisheries experts to acknowledge that communities need to take more control in managing their natural resources. The paradigm shift in fisheries management from a top-down resource orientated control to a participatory people-centred control is now being advocated in many maritime nations in facilitating community-based natural resource management. At the heart of these projects is the establishment of institutions and social networks that allow for clear communication and information sharing, based on scientific data and traditional knowledge which ultimately allow empowered communities to collectively manage their resources in partnership with government, market actors and many other stakeholders. Central to the problem is the issue of access rights. In many situations where co-management of natural resources through community-government partnerships is advocated, the failure of coastal states to provide adequate legislature and regulatory frameworks has jeopardised such projects. A second issue is the failure of many states to provide adequate investments in social and human capital which will enable communities to become the primary stakeholder in the co-management of their natural resources. Whilst investments like capacity building, education, skills training and development, communications and institution building can initially require high financial investments, the regulatory costs for monitoring, controlling and surveying fish stocks along the coastline will go down as communities take ownership of their resources under sustainable awareness. The main unit of investment therefore is social capital which allows for the increase in trust, cooperativeness, assertiveness, collective action and general capabilities of natural resource governance. High levels of social capital require good social relations and interactions which ultimately create a social network of fishers, community members and leaders, government officials, market players, researchers and various other stakeholders. Co-management thus has an inherent network structure made up of social relations on a horizontal scale amongst community members as well as on a vertical scale with government and fisheries authorities. These bonding relations between people and the bridging relations with institutions provide the social capital currency that allows for a successful co-management solution to community-based natural resource governance. The South African coastline is home to thousands of people who harvest the marine resources for food security and securing a basic income. Fishing is a major cultural and historical component of the livelihoods of many people along the coastline, particularly along the Wild Coast of South Africa located on its South-eastern shoreline. Due to the geopolitical nature of South Africa’s apartheid past many people were located in former tribal lands called Bantustans. The Transkei, one of the biggest homelands, is home to some of South Africa’s poorest people, many of whom rely on the marine resources. By 1998 the government sought to acknowledge the previously unrecognised subsistence sector that lived along the South African coastline with the promulgation of the Marine Living Resources Act. The act sought to legalise access rights for fishers and provide opportunities for the development of commercial fisheries. The act and many subsequent policies largely called for co-management as a solution to the management of the subsistence sector. This thesis largely explains the administrative and legislative difficulties in transporting the participatory components of co-management to the ground level. As such co-management has largely remained in rhetoric whilst the government provides a contradictory policy regarding the management of subsistence and small-scale fishers. This thesis attempts to provide qualitative ethnographic research of the East Coast Rock Lobster fishery located in a small fishing village in the Transkei. The fishery falls somewhere on the spectrum between the small-scale and subsistence sector as there are a basket of high and low value resources being harvested. It will be argued that in order to economically and socially develop the fishery the social capital and social networks of the community and various stakeholders needs to be analysed in order to effectively create a co-management network that can create a successful collective management of natural resources thereby sustaining these communities in the future.
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Social networks in recently established human settlements in Grahamstown East/Rhini, South Africa
- Authors: Mukorombindo, Yeukai Chido
- Date: 2012
- Subjects: Social networks -- South Africa -- Grahamstown Human settlements -- South Africa -- Grahamstown Social capital (Sociology) Grahamstown (South Africa) -- Social life and customs Poor -- Social networks -- South Africa -- Grahamstown Grahamstown (South Africa) -- Social conditions Social change -- South Africa -- Grahamstown Informal sector (Economics) -- South Africa -- Grahamstown
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3310 , http://hdl.handle.net/10962/d1003098
- Description: This thesis attempts to understand the concepts of social capital and social networks within the South African government’s current policy on “human settlements”. It considers the association between social networks, social capital and social cohesion, community development and improved general quality of life. The thesis also explores the possibility and challenges of using social capital and social networks amongst low income urban communities as a viable strategy against poverty and for the development of sustainable human settlements. The thesis will examine the nature and form in which informal social networks function in a low income urban community in South Africa and the benefits that arise from these. The thesis particularly looked at informal social security networks in the form of savings clubs/stokvels and burial societies as well as other informal social networks such as religious associations and neighbourhood social support groups. The study discovered that in light of the high unemployment rate, high poverty levels and increasing urban economic pressures, most low income households cannot access or rely on social networks as a means of survival but on grants and wages. Social security networks are only accessible to those who can afford monthly membership contributions thereby excluding the poorest of the poor. For those who can afford to be members of social security networks, the benefits are limited and they do not adequately address household needs. The study also showed how those who cannot afford to be members of social security networks still have access to some sort of communal social support. Neighbours stand out as valuable in this regard. However, the casual neighbourhood support networks are not ‘resource rich’ mainly due to, the inability of people to donate and reciprocate. Religious networks are mainly identified with emotional, psychological and spiritual well-being, providing friendship, comfort and advice but these benefits are only provided to members only in their time of need. The theoretical understanding of social networks producing social capital which is seen as being beneficial to the poorest of the poor is questioned, as the results show the inequalities and divisions that exist within informal social networks themselves. On the other hand, all the social networks considered in this thesis have managed to contribute towards strengthening neighbourly relations, trust, building community identity and promoting values of ubuntu- sharing and caring for one another which in the long-run benefits the community, both members and non-members alike.
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Structural analysis of effects of mutations on HIV-1 subtype C protease active site
- Authors: Mathu, Alexander Muchugia Nganga
- Date: 2012
- Subjects: HIV (Viruses) -- Research , HIV infections -- Treatment -- Research , Protease inhibitors -- Research , Viruses -- Effect of drugs on -- Research
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4013 , http://hdl.handle.net/10962/d1004073 , HIV (Viruses) -- Research , HIV infections -- Treatment -- Research , Protease inhibitors -- Research , Viruses -- Effect of drugs on -- Research
- Description: HIV/AIDS is a global pandemic that poses a great threat especially in Sub-Saharan Africa where the highest population of those infected with the virus is found. It has far reaching medical, socio-economic and scientific implications. The HIV-1 protease enzyme is a prime therapeutic target that has been exploited in an effort to reduce morbidity and mortality. However problems arise from drug toxicity and drug-resistant mutations of the protease which is a motivation for research for new, safer and effective therapies. Evidence exists to show that there are significant genomic differences in Subtype B and C that have a negative effect on the intrinsic binding of inhibitors. It is imperative to look at all perspectives from epidemiological, molecular to the pharmacological ones so as to achieve rational design of therapeutic agents. This study involved the use of in silico structural analysis of the effects of mutations in the active site. The data was provided by the National Institute of Communicable Diseases consisting of HIV-1 Subtype C protease sequences of 29 infants exhibiting drug-resistance to ritonavir and lopinavir. The major active site mutations causing drug resistance identified in this study were M46I, I54V and V82A using the Stanford HIV database tool. Homology modeling without extra restraints produced models with improved quality in comparison to those with restraints. MetaMQAPII results differed when models were visualized as dimers giving erroneous modeled regions in comparison to monomers. A broader study with a larger dataset of HIV-1 subtype C protease sequences is required to increase statistical confidence and in order to identify the pattern of drug resistant mutations. Homology modeling without extra restraints is preferred for calculating homology models for the HIV-1 subtype C. Further investigations needs to be done to ascertain the accuracy of validation results for dimers from MetaMQAPII as it is designed for evaluation of monomers.
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Structural analysis of prodomain inhibition of cysteine proteases in plasmodium species
- Authors: Njuguna, Joyce Njoki
- Date: 2012
- Subjects: Plasmodium , Cysteine proteinases , Proteolytic enzymes , Malaria -- Chemotherapy , Antimalarials , Plasmodium falciparum
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4021 , http://hdl.handle.net/10962/d1004081 , Plasmodium , Cysteine proteinases , Proteolytic enzymes , Malaria -- Chemotherapy , Antimalarials , Plasmodium falciparum
- Description: Plasmodium is a genus of parasites causing malaria, a virulent protozoan infection in humans resulting in over a million deaths annually. Treatment of malaria is increasingly limited by parasite resistance to available drugs. Hence, there is a need to identify new drug targets and authenticate antimalarial compounds that act on these targets. A relatively new therapeutic approach targets proteolytic enzymes responsible for parasite‟s invasion, rupture and hemoglobin degradation at the erythrocytic stage of infection. Cysteine proteases (CPs) are essential for these crucial roles in the intraerythrocytic parasite. CPs are a diverse group of enzymes subdivided into clans and further subdivided into families. Our interest is in Clan CA, papain family C1 proteases, whose members play numerous roles in human and parasitic metabolism. These proteases are produced as zymogens having an N-terminal extension known as the prodomain which regulates the protease activity by selectively inhibiting its active site, preventing substrate access. A Clan CA protease Falcipain-2 (FP-2) of Plasmodium falciparum is a validated drug target but little is known of its orthologs in other malarial Plasmodium species. This study uses various structural bioinformatics approaches to characterise the prodomain‟s regulatory effect in FP-2 and its orthologs in Plasmodium species (P. vivax, P. berghei, P. knowlesi, P. ovale, P. chabaudi and P. yoelii). This was in an effort to discover short peptides with essential residues to mimic the prodomain‟s inhibition of these proteases, as potential peptidomimetic therapeutic agents. Residues in the prodomain region that spans over the active site are most likely to interact with the subsite residues inhibiting the protease. Sequence analysis revealed conservation of residues in this region of Plasmodium proteases that differed significantly in human proteases. Further prediction of the 3D structure of these proteases by homology modelling allowed visualisation of these interactions revealing differences between parasite and human proteases which will lead to significant contribution in structure based malarial inhibitor design.
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Teachers' leadership roles at a public rural school in the Ohangwena Region, Namibia
- Authors: Nauyoma-Hamupembe, Ladipaleni Ndadiinina
- Date: 2012
- Subjects: Educational leadership -- Namibia -- Ohangwena Rural schools -- Namibia -- Ohangwena School management and organization -- Namibia -- Ohangwena Teachers -- Namibia -- Ohangwena Teacher-principal relationships -- Namibia -- Ohangwena
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1794 , http://hdl.handle.net/10962/d1003679
- Description: The changing global and local circumstances and shift for democracy posed particular problems for school administration and leadership and made it difficult for principals to fulfil leadership responsibilities in schools alone. Hence principals require the assistance of all stakeholders in the school, and teachers in particular, to work together as a team and share the diverse leadership load for the improvement of schools. Thus, leadership in schools needs to be shared and distributed in a collaborative manner among teachers and principals working as a group to accomplish the primary objective of their schools, which is to improve learners’ achievement. For this idea to be embraced, I suggest it may require an urgent need for advanced knowledge and understanding of teacher leadership in schools, among teachers and principals, if schools are to thrive. This research studied the phenomenon of teacher leadership at a public rural school in the Ohangwena region of Namibia. It explored the teachers’ experiences of their leadership roles, and specifically the challenges inherent within the practice of teacher leadership in a school. A qualitative interpretive case study was conducted, employing document analysis, semi‐structured interviews and observations to produce data with regard to teachers’ experiences of their leadership roles, challenges inherent within its practice and possible strategies to promote teacher leadership. The analysis and the triangulation across the data sets suggested that teacher leadership existed in the case study school where it appeared in four different areas of leadership practice. These areas of leadership practices (Grant, 2008, p. 93) were, for example, in the classroom, outside the classroom in curricular and extra‐curricular activities, in school‐wide leadership development and between other neighbouring schools in the community. The school had a view of teacher leadership which was strongly located within the classroom and outside the classroom in curricular and extra‐curricular activities where teachers worked and interacted with their colleagues and learners. Teacher leadership was severely limited in the area of whole school development and almost non‐existent in the area outside the school between teachers across neighbouring schools, at circuit or district level and in the community. The study suggested that the nature of teacher leadership in the case study school was a restricted form of teacher leadership (Harris and Muijs, 2005) due to a range of factors which impeded its practice. The factors were, for example, a lack of involvement of all teachers in whole school leadership and school‐wide decision‐making. Other factors were limited time for teachers in the school, a lack of leadership development amongst the principal and teachers as well as resistance for teachers to leadership in the case study school.
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The analysis of the strain level and the predicted human error probability for critical hospital tasks
- Authors: Burford, Eva-Maria
- Date: 2012
- Subjects: Nursing errors -- South Africa -- Prevention , Nursing -- South Africa -- Psychological aspects , Hospitals -- Employees -- Health and hygiene -- South Africa , Nursing -- Job stress -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5104 , http://hdl.handle.net/10962/d1005182 , Nursing errors -- South Africa -- Prevention , Nursing -- South Africa -- Psychological aspects , Hospitals -- Employees -- Health and hygiene -- South Africa , Nursing -- Job stress -- South Africa
- Description: South African hospitals, as a result of numerous factors, have the problem of an increasing workload for nursing staff, which in turn may affect patient treatment quality. This project aimed at addressing patient treatment quality specifically from the perspective of worker capabilities by investigating the strain level and predicted human error probability associated with specific patient-centered tasks in the South African health care sector. This was achieved through two independent yet interlinked studies which focused on seven patient-centred tasks. The tasks analysed were the tasks of setting up and changing intravenous medication, administering injection and pill medication, measuring blood glucose, temperature and heart rate and blood pressure. In the first study, work environment and task characteristics, task structure and execution were analysed. In addition to the task execution, the resulting strain levels, in the form of heart rate measures and subjective ratings of workload, were studied. The second study determined the error protocols and predictive error probability within the healthcare environment for the seven pre-defined tasks. The results for the first study established that different organizational and environment factors could affect task complexity and workload. The individual task components and information processing requirements for each task was also established. For the strain analysis, significant results for the tasks were determined for heart rate frequency and the heart rate variability measures, but some of these were contradictory. For the second study, specific error protocols and error reporting data were determined for the hospital where this research was conducted. Additionally the predictive error probability for the pre-defined tasks was determined. This combined approach and collective results indicate that strain and predictive error probability as a result of task workload can be determined in the field as well as being able to identify which factors have an effect on task strain and error probability. The value of this research lies in the foundation that the gathered information provides and the numerous potential applications of this data. These applications include providing recommendations aimed at improving nursing work environment with regards to workload, improving patient treatment as a result of a reduction in errors and the potential foundation these results provide for future research
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The development of an orodispersible sildenafil citrate tablet intended for paediatric use
- Authors: Dagnolo, Bianca
- Date: 2012
- Subjects: Drug development -- Children -- Research -- South Africa , Pulmonary hypertension -- Children -- Research , Tablets (Medicine) -- Development , Pharmaceutical chemistry -- Research
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3751 , http://hdl.handle.net/10962/d1003229 , Drug development -- Children -- Research -- South Africa , Pulmonary hypertension -- Children -- Research , Tablets (Medicine) -- Development , Pharmaceutical chemistry -- Research
- Description: Sildenafil citrate (SC) is a phosphodiesterase-5 inhibitor that is used to treat pulmonary hypertension (PH) in paediatric patients. The purpose of these studies was to develop a formulation and manufacture an orodispersible tablet (ODT) that can be easily administered to neonates and children with PH. The advantages of ODT dosage forms include ease of administration, rapid dissolution of the API, SC. Furthermore the dosage form can be taken without water which is beneficial to patients without immediate access to potable fluids. A simple, rapid, accurate, precise and selective reversed-phase HPLC method was developed and validated in accordance with International Conference on Harmonization (ICH) guidelines and was successfully used for the analysis of SC as raw material and in SC containing pharmaceutical dosage forms. Preformulation studies were performed on SC, alone and in combination with potential excipients that could be used to make tablets. Investigations into potential interactions between SC and the excipients were performed using Differential Scanning Calorimetry (DSC) and Infrared Spectroscopy (IR). DSC results revealed that SC was compatible with all potential excipients except mannitol and magnesium stearate. However these interactions were not observed with IR and therefore it was concluded that the interactions were induced by the high temperatures that DSC operates at. Particle size and shape was also established by use of Scanning Electron Microscopy (SEM) and flow properties were monitored by calculating Carr’s Index (CI) and the Hausner Ratio (HR). Direct compression was used as the method of manufacture for SC tablets as this approach is simple and the most economic production approach. The powder blends were assessed for bulk and tapped density and the CI and HR were used to determine the flowability of the blends. The quality attributes of the resultant tablets that were monitored included uniformity of weight, friability, crushing strength, tensile strength, disintegration, wetting and in vitro dispersion times. Design of Experiments is an efficient statistical approach that has become a popular tool used in the pharmaceutical industry to optimize formulation compositions, as it allows for the investigation of several input factors at the same time whilst not using the tedious and traditional “ modification of one variable at a time” approach. A Central composite experimental design was chosen as the most appropriate means to optimize the formulation as it produces more accurate results as opposed to other experimental designs approaches as input factors are investigated at five different levels. Through the use of mathematical modelling, optimum concentrations of disintegrant(s) and an appropriate blending time were established. Analysis of the data from the experimental design and mathematical modelling studies reveal that no changes in disintegrant concentration or blending time altered the disintegration time of the formulation to any significant extent. This result is most likely due to the fact that the critical disintegrant concentration has been reached and increasing the disintegrant concentration further has no effect on disintegration time. It was also established that a change in the concentration of CMS and CRP altered the wetting time of the tablet significantly. Finally it was noted that there was a linear relationship between blending time and the uniformity of content of the tablets produced in these studies. The optimized product was a white tablet with a diameter of 7.31 mm with a thickness of 2.80mm.The dosage form had no visible cracks or evidence of picking or sticking. The tablet exhibits suitable friability and tensile strength while exhibiting a disintegration time of only 8s. Therefore an orodispersible tablet containing SC intended for paediatric use has been successfully developed, manufactured and optimized through the use of preformulation studies, appropriate quality control monitoring and mathematical modelling. These formulations require further optimization in respect of addition of flavours and or additional sweetening agents.
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The diet and ecological role of black-backed jackals, Canis Mesomelas, in two conservation areas in the Eastern Cape Province, South Africa
- Authors: Brassine, Mathilde Chloé
- Date: 2012
- Subjects: Black-backed jackal -- South Africa -- Eastern Cape , Jackals -- South Africa -- Eastern Cape , Jackals -- Food , Wildlife conservation
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5660 , http://hdl.handle.net/10962/d1005344 , Black-backed jackal -- South Africa -- Eastern Cape , Jackals -- South Africa -- Eastern Cape , Jackals -- Food , Wildlife conservation
- Description: Mammalian predators are keystone species and can have disproportionately large impacts, relative to their abundance, on the communities and ecosystems they inhabit. In addition, predator-prey interactions (including bottom-up and top-down effects) are the fundamental linkage among species in food webs. Thus, understanding the food requirements of predators is imperative. There have been no comprehensive studies on the diet of black-backed jackals (Canis mesomelas) across a full seasonal cycle in the Albany Thicket Biome of the Eastern Cape Province. This biome is rich in plant diversity, is highly nutritious for herbivores and supports a large number of mammalian species, yet it is poorly conserved. The aim of the present study was to establish the diet of black-backed jackals on two conservation areas where thicket vegetation dominates (Great Fish River Reserve and Kwandwe Private Game Reserve). The diet was assessed using scats collected monthly from June 2009 to May 2010 and a sample of 25 stomachs over the same period. At both sites and across all seasons, mammalian hair was encountered most often (93% of all scats) and a total of 23 mammal species were consumed. Of the mammals recorded in the scats, hair from several ungulate species was encountered most frequently and these were mostly hider species (offspring hidden in tall vegetation just after birth). On a seasonal basis, the proportion of mammalian hair was lowest in autumn. However, the contribution of fruits (Carissa haematocarpa, Diospyros lycioides and Grewia robusta) to the diet was significantly higher during this season. This suggests that black-backed jackals may employ diet switching in the Eastern Cape as a mechanism to capitalise on seasonally abundant food sources. Based on the stomach content analysis, invertebrates were consumed as frequently as mammalian prey throughout the year but mammalian prey was recorded in greater quantity (i.e. volume and mass). Thus, scat analysis may have overestimated mammalian prey and fruits and underestimated the importance of invertebrates, particularly highly digestible species (e.g. termites). In spite of these differences, scat analysis demonstrated similar general and seasonal trends as the stomach content analysis. Thus, scat analysis can provide an efficient and relatively accurate source of information on the diet of blackbacked jackals in the Eastern Cape. Both stomach content and scat collection methods depicted the black-backed jackal as a generalist and opportunistic predator, mainly relying on mammals and invertebrates. Although the results of my study suggest that black-backed jackal may be important predators of certain ungulate species, further study on their prey preferences, actual biomass ingested and the effects on the population viability of prey species is required in order to develop a robust management plan for the species in the protected areas of the Eastern Cape.
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The diet of black-backed jackal (Canis Mesomelas) on two contrasting land-use types in the Eastern Cape Province, South Africa and the validation of a new analytical method of mammalian hair identification
- Authors: Forbes, Ross William
- Date: 2012
- Subjects: Black-backed jackal -- South Africa -- Eastern Cape , Jackals -- South Africa -- Eastern Cape , Jackals -- Food , Mammals -- Identification
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5661 , http://hdl.handle.net/10962/d1005345 , Black-backed jackal -- South Africa -- Eastern Cape , Jackals -- South Africa -- Eastern Cape , Jackals -- Food , Mammals -- Identification
- Description: Diet assessments are critical for understanding the foraging behaviour, habitat use and trophic separation of mammalian predators and are vital for gaining insight into how predators influence prey populations. The aim of this research was to qualitatively describe the diet of black-backed jackals (Canis mesomelas, Schreber 1775) using scat analysis on two contrasting land-use types in the Eastern Cape Province, South Africa. Scats were collected on a monthly basis from November 2009 to October 2010 from two game reserves (Great Fish River Reserve and Shamwari Private Game Reserve) and two neighbouring livestock farms. The relative frequency of occurrence of mammal hair (33 – 47 %) and vegetation (32 – 45%)dominated jackal diet throughout the year across the four study sites. Other important prey items included invertebrates (8 – 21 %) and fruit and seeds (3 – 11 %). Birds and reptiles constituted ≤ 2 % of the diet and were only recorded on the game reserves. Significant seasonal dietary shifts were observed on the game reserves but not on the farms. Fruit and seeds were significantly more frequent in the diet during autumn at Great Fish River Reserve and invertebrates were significantly less common in the diet during winter on both reserves. In addition, vegetation was significantly more common in the diet during winter at Shamwari Private Game Reserve. The significant temporal variation of certain prey items is testament to black-backed jackals being opportunistic generalists, foraging on those food items which are most abundant, accessible and energetically beneficial. Land-use type also influenced the diet of black-backed jackals with significantly more invertebrates and, fruit and seeds being recorded on the game reserves than on the farms. By contrast, significantly more mammal hair and vegetation were present in the diet on the farms compared with the game reserves. The mammalian component of the diet was dominated by ruminants and rodents on the game reserves and by ruminants and livestock on the farms. The presence of livestock in the diet of black-backed jackals on the farms highlights their potential impact on the livestock industry in the region and may assist farmers in determining which predators are responsible for stock loss. Previous approaches for identifying mammalian hairs from predator scats have utilised dichotomous keys and reference collections but these are often time-consuming and require a trained individual to carry out the identification. Thus, I also tested the efficacy of an automated pattern recognition programme (HairSnap) for identifying mammalian hairs from black-backed jackal scats. The overall accuracy of the programme was 38 % with black-backed jackal, Greater kudu (Tragelaphus strepsiceros) and striped polecat (Ictonyx striatus) hairs being accurately identified more often (70 – 80 %) than any other species tested. It is likely that both the size and species composition of the sample resulted in the poor accuracy of the programme. However, with the implementation of several improvement measures (e.g. adjustment of the algorithm) the programme may offer a superior, bias-free method of mammalian hair identification. The dietary information gathered here furthers our knowledge of the biology of the blackbacked jackals, especially in the locally important thicket biome. Moreover, understanding their foraging habits allows for more effective management of the species on both game reserves and farmlands. I recommend that future research should focus on quantitatively assessing the diet of black-backed jackals in the Eastern Cape Province and elsewhere. This will compliment the dietary description provided in this study and may offer a biologically more meaningful indication of the relative importance of the prey items.
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The dionysian in performance reclaiming the female transgressive performing body
- Authors: Solomon, Zanne
- Date: 2012
- Subjects: Dionysia , Feminism and theater , Human body in literature , Performance art , Performing arts , Body image in women , Self-perception in women , Human body -- Social aspects
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2148 , http://hdl.handle.net/10962/d1002380
- Description: In this thesis I investigate the theoretical or philosophical notion/archetype of the Dionysian in relation to the transgressive female body in performance. I do so through 1) an investigation into the theories behind the Dionysian and the transgressive; 2) an examination of the performative practice of the transgressive female body; and 3) a personal exploration of the theatrical practice. 1) In the first chapter I introduce and thoroughly explore the archetypal concept of the Dionysian, and identify its significance because of its intrinsic association with the transgressive. I associate it with its oppositional force, the Apollonian, which is similarly significant because it is through the Dionysian disruption of the Apollonian from which the very notion of the transgressive springs. Through a review of Camille Paglia's seminal text on the subject of the Dionysian¹, this chapter provides a historical, mythological and theoretical context for the schism between the two archetypal aesthetics, starting from the description of the mythology of the ancient Greek gods, Dionysus and Apollo, and unpacks the transgressive nature of the Dionysian. Drawing on concurring theories of Friedrich Nietzsche and Julia Kristeva, as well as Hans Thies-Lehmann's writings on post-dramatic theatre², Chapter One attempts to firmly establish the inherent link between the Dionysian and theatre and performance, as well as the Dionysian and the transgressive, and provide a thorough theoretical framework for the rest of the thesis. 2) The second chapter investigates the work of two female performance artists³ who (re)present⁴ their bodies as transgressive in performance, namely Marina Abramovic and Karen Finley. It critically examines specific performance works of theirs, and through this examination it explores how they (re)present their bodies as transgressive in performance, and why they do so. This chapter furthermore establishes the connection between the transgressive female performing body, as (re)presented by Abramovic and Finley, and the Dionysian. In so doing it explores how they negotiate this ancient aesthetic or practice in a contemporary performance context. I believe that these performance artists are in fact striving to celebrate and reclaim the Dionysian within their work, and I attempt to establish this within this chapter. 3) The third chapter of this thesis analyses my own practical exploration of the transgressive female body in performance in a piece entitled Bleeding Mermaid (2008). It examines this exploration in the context of the theory of the Dionysian, as well as investigating how and why I (re)presented my body as transgressive in the performance. The analysis furthermore questions how I understand my work on the (re)presentation of the transgressive female body in relation to, and within the context of, Finley and Abramovic's work on the same subject. Through this investigation, I aim to establish a link between the Dionysian and the transgressive female performing body; and investigate the motivation(s) behind the (re)presentation of the transgressive female body in performance. I hope to open up a pathway to the reclamation of the Dionysian, both in performance practice and research. ¹Paglia, Camille. Sexual Personae: Art and Decadence from Nefertiti to Emily Dickinson. England: Penguin Books, 1990. ²Lehmann, Hans-Thies. Postdramatic Theatre. Trans. and Intro. Karen Jürs-Munby. London and New York: Routledge, 2006. ³Performance Art began around the 1960s in Europe and America. It is performance with a sense of immediacy – in that it is hard to replicate as it interacts with each unique audience – it is thus effectively a fresh/new experience each time. It breaks the boundaries of traditional theatre (form, structure, venue, time etc) and is often shocking or provocative in nature. It mixed the aesthetics of theatre and art, often taking place in installation settings. Performance Art has developed and morphed throughout the years, and is also referred to as Live Art in Britain. A performance artist is someone who produces performance art. It is possible that Performance Art no longer exists/is possible because it no longer shocks or affects the audience. ⁴My use of the brackets in (re)presented/(re)present throughout this thesis is because I would like to make simultaneous reference to the words/connotations of "presentation" and "representation", without being bound to the connotations of illusion/falseness/non-reality as is associated with the word "representation" (in opposition to the concept of the "real"), and thus be left only with the one-dimensional approach/meaning of "presentation".
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The dispersal of African wild dogs (Lycaon Pictus) from protected areas in the Northern KwaZulu‐Natal Province, South Africa.
- Authors: Whittington‐Jones, Brendan Mark
- Date: 2012
- Subjects: African wild dog , African wild dog -- Conservation -- South Africa -- KwazuluNatal , African wild dog -- Dispersal -- South Africa -- KwaZulu-Natal , African wild dog -- Effect of human beings on -- South Africa -- KwaZulu Natal
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5893 , http://hdl.handle.net/10962/d1013414
- Description: The number of African wild dogs Lycaon pictus in Northern KwaZulu‐Natal, South Africa has increased substantially over the last six years. This is largely due to a managed metapopulation approach of introductions onto protected areas and private game reserves since 1998. Because of the increasing wild dog population, the likelihood of rural communities surrounding protected areas encountering dispersing wild dogs in northern KwaZulu‐Natal has also increased. Resident wild dog populations currently occur in Hluhluwe‐iMfolozi Park (HiP), Mkhuze Game Reserve (MGR) of Isimangaliso Wetland Park and Thanda Private Game Reserve (TPGR) all of which are bordered by a matrix of natural habitats and human settlements. Thus, land outside these protected areas could be utilized to expand wild dog distribution and provide connectivity between existing resident populations of wild dogs within KwaZulu‐Natal. To investigate the viability of such an approach, Maximum Entropy Modelling (Maxent) was used to characterize habitat niche selection of dispersing wild dogs, and to identify potential dispersal linkages between current wild dog metapopulation reserves. The model was calibrated using 132 location points collected from 2006 until 2009. From 2008 to 2009 I also conducted a survey of 247 community members in tribal authorities bordering HiP and MGR, to understand factors influencing attitudes towards wild dogs. A habitat suitability model with seven predictor variables had an AUC of 0.96 (SD = 0.02) and indicated four variables which best predicted probability of presence for dispersing wild dogs: elevation, road density, land cover and human density. The results suggest that elevation and land cover may be of greater influence for dispersing wild dogs than human density or activity. Elevation was the single most effective variable indicating a higher probability of presence for dispersing wild dogs in lower lying locations; peaking at approximately 200 – 300m a.s.l. Wild dogs also showed a preference for Woodland and Bushland habitats which in KwaZulu‐Natal tend to be found on lower lying topography. A preference for areas of lower human density and a highest probability of presence at road densities of approximately 0.7km/km2 or less would suggest that while wild dogs may show a tendency to avoid areas of high human activity, they can coexist in close proximity to humans. Respondent’s attitudes, knowledge of wild dogs and livestock husbandry were interpreted by the development of a set of indices. Attitudes were positively related to formal education levels and wild dog‐specific education, but were not influenced by demographic factors such as gender, age and employment status. Eighty three percent of respondents believed efforts to protect wild dogs should continue. Respondents with higher numbers of livestock tended to have more positive attitudes towards wild dogs despite generally incurring higher losses to carnivore depredation than those with less livestock. This appears to be because the financial burden of livestock losses to those with fewer livestock is perceived to be a loss of a greater proportion of total financial wealth. The study highlighted the substantial scope for improvement in livestock management. Theft (34 percent), drought (30 percent) and disease (14 percent) were ranked as the greatest problems facing livestock owners while predators were ranked as the greatest problem by only 4 percent of respondents. My findings suggest that wild dogs are generally viewed positively or with ambivalence. Concerns over the potentially increasing threat to livestock, as natural prey numbers outside protected areas decline and wild dogs disperse from natal packs, are likely to be manageable. However, wild dog population expansion within KwaZulu‐Natal will continue to rely on managed core populations on perimeter‐fenced metapopulation reserves with tolerant communities and landowners contributing to the connectivity of isolated reserves. Generation of tolerance can be instilled through continued advocacy and education, supported by conflict mitigation initiatives and rapid response to conflict reports. The implementation of incentive schemes for adjoining private landowners to co‐manage wild dog populations will need to be addressed in conjunction with managed metapopulation practices and law enforcement, to promote range expansion, and reduce potentially lethal edge effects and wild dog‐human conflict.
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The effect of dietary fish oil replacement with soybean oil on growth and health of dusky kob, Argyrosomus japonicus (Pisces: Sciaenidae)
- Authors: Rossetti, Nani Adami
- Date: 2012
- Subjects: Sciaenidae , Fish culture , Argyrosomus -- Growth , Argyrosomus -- Feeding and feeds , Argyrosomus -- Health , Fish oils as feed , Soy oil , Lipids , Eicosapentaenoic acid , Docosahexaenoic acid
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5272 , http://hdl.handle.net/10962/d1005116 , Sciaenidae , Fish culture , Argyrosomus -- Growth , Argyrosomus -- Feeding and feeds , Argyrosomus -- Health , Fish oils as feed , Soy oil , Lipids , Eicosapentaenoic acid , Docosahexaenoic acid
- Description: Lipids are essential components for fish because they contain fatty acids that are vital for regular growth and health. Fish oil is rich in eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which are essential fatty acids for carnivorous fish, and therefore this product has traditionally been used as the main source of lipids in fish feeds. However, with declining fisheries resources worldwide and the rapid expansion of the aquaculture industry pressuring this finite resource, such ingredients are becoming less available and more expensive. It is therefore necessary to explore the utilization of ingredients that are sustainable and competitive alternatives to fish oil in marine finfish feeds. This work investigated the effects of the substitution of fish oil with soybean oil on the growth performance, feed efficiency, fatty acid composition of the liver tissue and some health parameters in juvenile dusky kob, Argyrosomus japonicus; an increasingly popular sciaenid marine aquaculture species in South Africa. Six diets (18 % total lipid and 46 % protein) with increasing percentage substitution of fish oil with soybean oil (1, 14, 28, 42, 56 and 70 %) were fed to juvenile kob. After 84 days of feeding these diets to the fish, no significant differences in fish length and weight between treatments were observed. However, there was a significant trend of a decrease in specific growth rate, ranging from (± standard error) 0.87 ± 0.06 to 0.72 ± 0.04 % body weight day⁻¹, and condition factor, ranging from 1.59 ± 0.03 to 1.54 ± 0.02, with increasing vegetable oil replacement in the diets between days 56 and 84. There were no differences in red blood cell count, haematocrit and haemoglobin concentration after 206 days of feeding. However, visceral fat index (VFI) increased significantly from 1.08 ± 0.17 % for fish fed diets with 28 % soybean oil, to 2.24 ± 0.15 % for fish fed diets with 70 % soybean oil. Similarly, hepatosomatic index (HSI) increased significantly from 0.84 ± 0.08 % to 1.80 ± 0.12 % in the control diet and the 56 % soybean oil diet, respectively. After 206 days of feeding, fish fed diets with 42 to 70 % soybean oil showed greater number of lipid vacuoles in the liver, which were also larger in size, and hepatocytes nuclei were displaced to the cell periphery. The fatty acid composition of the liver tissue strongly corresponded to the fatty acid composition of the diets. Linoleic acid accumulated in the liver of the fish fed increasing soybean oil in the diets. In contrast, EPA and DHA decreased from 13.63 to 1.97 %, and 14.34 to 3.28 %, respectively, in the liver tissue of fish fed diets with increasing soybean oil content; consequently the n-3/n-6 ratio was also significantly reduced with inclusion of vegetable oil in the diets. The trend of decreasing growth rate with increasing oil replacement towards the end of the trial corresponds with increases in VFI, HSI, as well as the fatty acid accumulation and lipid vacuoles in the liver. This suggests that dusky kob is less able to metabolise soybean oil at increased substitution levels which would account for the poorer growth at higher levels. The dependence of fish on dietary marine oil decreased significantly with each inclusion of soybean oil in the diets. Nonetheless, the calculations based on the nutrient ratio presented positive outcomes for all treatments, that is, values of marine oil dependency ratio were below one for all treatments. It is concluded that soybean oil can replace fish oil in formulated diets for dusky kob up to a level of 28 % of total dietary lipids, as evidenced by the good growth and feed efficiency, and no apparent negative health effects observed up to this level.
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