Participatory mapping, learning and change in the context of biocultural diversity and resilience
- Authors: Ali, Million Belay
- Date: 2012
- Subjects: Biodiversity conservation -- Research -- Ethiopia Cultural pluralism -- Research -- Ethiopia Ethnopsychology -- Research -- Ethiopia Adult education -- Research -- Ethiopia
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1689 , http://hdl.handle.net/10962/d1003572
- Description: This study set out to investigate the learning and change that emerged in and through participatory mapping in the context of biocultural diversity and resilience in rural Ethiopia. It did this through examining the learning and agency emerging from three participatory mapping practices (Participatory 3 Dimensional Modelling, sketch mapping and eco-cultural calendars) using two case study sites, located in the Bale Mountains and the Foata Mountains in Ethiopia, and honing in on in-depth reflective processes in two community contexts located within the broader case study sites, namely Horo Soba, Dinsho wereda in Bale; and Telecho, in Wolmera wereda, in the Foata Mountain complex. This study tried to answer three research questions related to participatory mapping: its role in mobilizing knowledge related to biocultural landscape, its role in learning and change, and its value in building resilience. The study used qualitative case study research methodology underpinned by critical realist philosophy, and used photographic ‘cues’ to structure the reporting on the cases. It used four categories of analysis: biocultural diversity, educational processes, learning and agency, in the first instance to report on the interactions associated with the participatory mapping practices as they emerged in the two case study sites. This was followed by in-depth analysis and interpretation of participatory mapping and biocultural diversity, as well as participatory mapping and learning, with an emphasis on acquisition, meaning making and identity formation processes. The in-depth analysis drew on social and learning theory, and theory of biocultural diversity and social-ecological resilience. The study also included analysis of broader change processes that were related to and emerged from the social interactions in the mapping activities, and the resultant morphogenesis (change), showing that morphogenesis, while broadly temporal, is not linear, and involves ‘little iterative morphogenic cycles’. These insights were then used to interpret how participatory mapping may contribute to resilience building in a context where social-ecological resilience is increasingly required, such as the two case study sites, where socialecological degradation is highly visible and is occurring rapidly. The study’s contribution to new knowledge lies in relation to the role of participatory mapping in facilitating learning, agency and change which, to date, appears to be under-theorised and under-developed in the participatory mapping and environmental education literature. As such, the study findings provide in-depth insight into how participatory mapping methodologies may ‘work in the world’, in contexts such as those presented in the two cases under study. It has tried to demonstrate how participatory mapping has managed to mobilize knowledge related to biocultural diversity, facilitated the acquisition of knowledge and helped members of the community to engage in meaning making activities relevant to their biocultural landscape and renegotiate their identity within the wider community context. It has also shown that dissonance is an important dynamic in the learning process; and that morphogenesis (or change) occurs over time, but also in smaller cycles that interact at different levels; and that participatory mapping cannot, by itself mobilise significant structural change, at least in the short term. It has also shown, however, that learning and the desire for change can emerge from participatory mapping processes, and that this can be utilized to adapt to the changing socio-ecological environments, potentially contributing to longer term resilience of social-ecological systems.
- Full Text:
- Date Issued: 2012
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.
- Full Text:
- Date Issued: 2011
Commercial maritime higher education needs in South Africa
- Authors: Allison, Lee-Ann
- Date: 2020
- Subjects: Marine resources
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/47496 , vital:40117
- Description: Seaborne cargo trade accounts for over 80% of the physical volume of global trade. Maritime transport thus fulfills an integral function in the economy of the world. South Africa generates approximately 3.5% of the world’s seaborne trade by value and 1.61% by tonnage, but the business of shipping all that cargo is undertaken by foreign firms. Operation Phakisa, the Comprehensive Maritime Transport Policy, and the South African Maritime Road Map, in pursuance of the National Development Plan, aim to revive the commercial maritime sector. In order to meet the demand for the skills and innovative abilities sought at executive and managerial levels in the commercial maritime sector, higher education in the knowledge of maritime business is increasingly becoming a prerequisite. Investment in higher education of quality and relevance in the maritime field would contribute to achieving the goals of the government for harnessing the potential of South Africa’s blue economy. The literature is researched in order to establish an authoritative view that the knowledge and the inspiration for entrepreneurial activity in the maritime sector can be imparted through higher education; and for example, that a viable shipping sector can contribute to the growth of a country’s economy. The South African maritime sector is then described. The commercial maritime higher education available at universities and other institutions of higher learning in South Africa, as well as in other African countries and elsewhere in the world, is examined, in order to be able to identify the degree and diploma courses available. Maritime courses imply not only the content of the educational material, but also the method whereby the knowledge is instilled in learners, and which extends well beyond the classroom. A survey, by way of the personal interviews of leaders in maritime business, maritime government affairs, and academics teaching maritime topics, is then undertaken to ascertain their views on the education required to promote the maritime sector in South Africa, using the list of subjects available for study worldwide, to assist their choice. The literature research and the interview survey by design also enable the secondary aims of the study to be achieved. Those aims include determining how awareness of the maritime domain could be raised and how co-operation between academia, business, and government, known as the triple helix could be organized, to promote the growth of the maritime sector. The results of the survey are analyzed and tabulated, in order to illustrate the extent of the agreement between those interviewed and the conclusions reached. These conclusions establish: (i) that the commercial maritime education currently available in South Africa, is inadequate to meet the aim of the government to the sector; (ii) that a post-graduate degree iv in the specified maritime studies incorporating a period of internship, and following on the first degree in business subjects, is required; (iii) that a triple helix of co-operation between academia, business, and the government is essential to grow the commercial maritime sector in which South African entrepreneurs educated in such business will have the advantage; (iv) that greater awareness of the maritime domain is essential in South Africa if entrepreneurship in maritime business is to be cultivated; and (v)that such awareness can be cultivated in various ways; but it should start by including more maritime topics in the current school curricula.
- Full Text:
- Date Issued: 2020
A structural investigation of the sulphated polysaccharide from Aeodes ulvoidea Schmitz
- Authors: Allsobrook, Anthony John Robert
- Date: 1973
- Subjects: Red algae -- Composition Polysaccharides
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4437 , http://hdl.handle.net/10962/d1007482
- Description: Aeodes ulvoidea, a red seaweed of the Grateloupiaceae, yielded a highly sulphated polysaccharide which was shown to contain D- and L-galactose, 4-0-methy-L-galactose, 2-0-methyl - D- and L-galactose and 6-0-methyl-D-galactose, together with chromatographic traces of xylose and mannose. The sulphate was not labile to alkali, but it was largely removed with methanolic hydrogen chloride. Periodate oxidation of the polysaccharide, methylation of the de sulphated polysaccharide, and investigation of fifteen oligosaccharides from partial hydrolysis and acetolysis studies of the polysaccharide, indicate that (a) the polysaccharide is composed of a backbone of D-galactose residues which are 1,3- and 1,4-linked (b) at least some regions of alternating structure do occur (c) the 2-0-methylgalactose is linked through the 4-position (d) the 4-0-methyl-L-galactose is present as single unit side chains glycosidically linked to the galactose backbone at position 6, and (e) most of the 6-0-methyl-D-galactose is linked to the 4-position of 2-0-methyl-D-galactose.
- Full Text:
- Date Issued: 1973
Construction material logistics management: the case of North-Central Nigeria
- Authors: Alumbugu, Polycarp Olaku
- Date: 2019
- Subjects: Construction industry -- Nigeria
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/44556 , vital:38132
- Description: The Management of Construction Material Logistics Systems plays a significant role in meeting the goals of cost, quality and time to completion of a construction project. Fundamentally, it is accepted that any inefficiency in the delivery of construction material could lead to a time overrun and thus, a rise in construction costs. Therefore addressing the operational performance of logistics would have a positive impact on the goals of a construction project. The aim of this study was to investigate and evaluate the operational performance of material logistics in North-Central Nigeria as there is little specific research conducted on its effectiveness and efficiency. The methodology used included an extensive literature review and a field study conducted on ten quantitative approach that is rooted in the positivist paradigm, and purposive sampling techniques, was adopted. The descriptive method of data analysis was employed, and the findings and interpretations presented through graphs and images. Analysis of the findings led to the conclusion that material logistics did not operate as a system. There was almost no collaboration and integration of the logistics systems to create a synergistic interrelationship between functions in pursuit of higher overall effectiveness and efficiency. Improvement was needed in warehouse and transport operations and processes; technology and automation of logistics operations were absent, and delivery of material to customers was not effective. The implication was that the current materials logistics system did not meet the delivery goals of cost, quality and time of a construction project. The recommendations suggested included the adoption of the framework developed in this study. This would serve as a guide towards effective and efficient logistics management for material manufacturing firms, and for construction professionals.
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- Date Issued: 2019
A theoretical model for successful management of revenue for beneficiary communities of renewable energy companies in South Africa
- Authors: Amansure, Ricardo Julian
- Date: 2017
- Subjects: Strategic planning -- South Africa , Social responsibility of business -- South Africa , Renewable energy sources -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/7408 , vital:21351
- Description: The Renewable Energy (RE) sector is one of the fastest growing new industries in the Republic of South Africa (RSA). The Bloomberg New Energy Finance Climate Scope Report recently ranked RSA third globally, behind China and Brazil, and first among African countries for investment in clean energy (Glickman, 2014). However, one of the main benefits to be derived from the industry, that of socio-economic and enterprise development, is not being achieved owing to unsuccessful management of revenue for beneficiary communities in the renewable energy sector in RSA. Challenges relating to good governance and long-term planning are causing significant harm to communities that are already vulnerable, and are threatening to have a negative effect on the industry’s ability to fulfil its obligation to alleviate and, ultimately, eradicate poverty in some of the poorest communities in RSA.The primary objective of this study is to develop a model for the successful management of revenue for beneficiary communities in the renewable energy sector in South Africa. The model will provide guidance for enterprises, stakeholders, industry experts and community development practitioners within the renewable energy sector towards a pro-active, effective, and relevant decision-making process to achieve success in managing revenue for beneficiary communities. To address the primary objective, a number of secondary objectives were established by developing a conceptual model comprising variables identified in a comprehensive survey of the related literature. A path diagram, based on the formulation of appropriate hypotheses, was constructed between the independent variable and subsequent intervening and dependent variables. Primary data sourced from the identified national and international population of project management practitioners were collected by means of an electronic measuring instrument. The data were analysed and tested empirically by means of Structural Equation Modelling (SEM). The determinants that were identified through a review of the literature as influencing the success of managing revenue for beneficiary communities of renewable energy companies in South Africa included: the use of outside advice, strategic financial services, strategic planning, strategic partnerships, infrastructure development and project management. In order to achieve the objective, the following research questions were formulated: What is the influence of external factors such as outside advisers and support services on the perceived success of managing revenue for beneficiary communities of renewable energy companies in South Africa? The purpose of this research, therefore, was to evaluate and recommend new methodologies to the renewable energy sector by introducing a model of perceived success in managing revenue for beneficiary communities of renewable energy companies in South Africa. The study provided new insight into managing revenue for beneficiary communities in RSA. With the renewable energy sector being one of the fastest growing sectors in the RSA, and the RSA Government being determined to link the location of renewable energy facilities to economic development, this research has given new insight into managing revenue for SED and ED. The objectives of multi-sector participation, transformational change and sustainable initiatives for beneficiary communities could ensure greater consideration and care when managing beneficiary revenue. Thereby, the opportunity presented by the RE industry for beneficiary communities can change these communities dramatically for the better. The study makes a valuable contribution to the body of knowledge about managing revenue for beneficiary communities. The proposed model has led to a better understanding of the determinants that influence the success of managing revenue for beneficiary communities, namely: distinctive benefits (a combination of two variables: outside advice and support services), financial management, developmental benefits (a combination of two variables: infrastructure development and education), human development, project management and strategic planning. The study has also opened up new avenues of research into this subject.
- Full Text:
- Date Issued: 2017
Public procurement reforms in Ghana: impact on the growth of the local construction industry
- Authors: Amoah, Christopher
- Date: 2017
- Subjects: Government purchasing -- Ghana Construction industry -- Ghana
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/15862 , vital:28285
- Description: Public procurement reform has become a modern phenomenon where various countries are reforming their procurement systems either to make the systems more efficient, transparent, achieve value for money, reduce or eliminate corrupt activities, to meet the requirements of donor countries or to make the system meet the international standards. Some countries also use public procurement reform as a policy tool to address socio-economic issues including the promotion of local sectors and disadvantaged groups. Ghana has not remained stagnant in this regard but has followed suit in reforming its procurement systems to address the weaknesses of the past procurement practices. However, the effectiveness of these reforms in promoting the local construction firms has not been investigated. This research therefore, investigated how the various procurement reforms instituted by the government of Ghana have impacted on the growth of the Ghanaian construction sector. A comprehensive review of the related literature revealed that there is a relationship between public procurement reforms and the growth of the local sectors as various governments in the past have managed to use their procurements levers as policy tools to address the imbalances in the socio-economic development of their citizens. A phenomenological (qualitative) research approach was adopted for this study. Accra, the capital of Ghana was chosen based on its strategic position and also because of massive construction activities currently taking place in the city. Again, many construction firms are also registered and operating in this city. The research instrument used is the interview guide made of both tick box and open ended questions. Other sources of data included archival records such as contracts awarded, the current public procurement regulations, and manuals. It was concluded after the analysis of the findings that, even though public procurement reforms have brought about improved procurement practices, the reforms have failed to have a positive impact on the growth of the local construction industry. The implication is that, the construction industry in Ghana is still dominated by foreign firms executing major government projects to the detriment of the local construction firms thereby stifling their growth. The findings also revealed that local contractors only executive minor works devoid of complexities and mainly engaged as subcontractors by foreign firms on major government projects. The findings also revealed that government has so far not instituted any radical protective laws in the procurement systems to protect the local construction firms. The research has produced a tender evaluation template with protective mechanisms such as awarding points to bidders during the tender evaluation process. The research has also produced tender evaluation formulas for calculating points for bidders and how the successful bidder is arrived at. The study provides recommendations to all stakeholders in the Ghanaian construction industry and proposes that the evaluation criteria produced by this study be used in the public procurement system to help grow the indigenous construction industry.
- Full Text:
- Date Issued: 2017
Multivariate morphometric analysis and behaviour of honeybees (Apis Mellifera L.) in the southern regions of Ethiopia
- Authors: Amssalu, Argaw Bezabeh
- Date: 2003
- Subjects: Honeybee -- Ethiopia -- Behavior Honeybee -- Ethiopia
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5616 , http://hdl.handle.net/10962/d1003130
- Description: Morphometric and behavioural characteristics of honeybees, Apis mellifera were analysed using multivariate and bivariate statistical methods to characterise honeybees of southern Ethiopian region. A total of 33800 morphometric character measurements were taken from 2600 individual worker honeybees of 130 honeybee colonies collected at 26 sampling localities with an average inter-locality distance of 89km to determine the occurrence of morphoclusters. 117 experienced farmer beekeepers and beekeeping experts were interviewed on pre-tested questionnaire to investigate the behavioural characteristics of these honeybees in their respective areas. Morphometric characters associated with pigmentation and body size exhibited a higher discriminant power while forewing venation angles (B4, N23 and 026) lack discriminatory power to segregate honeybees in the southern Ethiopian region. Principal components and discriminant analyses using the most discriminatory morphological characters delineated four statistically distinct morphoclusters in the southern Ethiopian region: the smallest and yellow honeybees, A. m. woyi-gambella which are different from all African honeybees, occur in the western and southern lowlands; the small and yellowiest honeybees, Apis mellifera jemenitica in the eastern escarpment; the largest and darkest honeybees, Apis mellifera bandasii in the central and eastern highlands; and dark honeybees, Apis mellifera scutellata in the wet tropical forests. High intracolonial and intercolonial variances within and between the boundaries of the honeybee groups were detected. The former suggests areas of ecological instability, while the latter areas of transitional or natural hybridisation zones. These areas are characterised by transitional ecological zones having intermediate climate and physiography. Even though honeybees of the southern Ethiopian region are generally dark and small, they show a high tendency to reproductive swarming, migration and aggressiveness, great variation in pigmentation, size and behaviour were observed both within and between the groups. A. m. jemenitica honeybees have a high propensity to migration and less a tendency for reproductive swarming. A. m. bandasii and A. m. scutellata have a high inclination to reproductive swarming and the former has a lesser and the later intermediate propensity to migration. A. m. woyi-gambella honeybees have intermediate swarming and migration tendencies. These results revealed that reproductive swarming and migration are higher in resource-rich and resource-poor areas respectively. Honey plants of the central highlands of Ethiopia are predominantly herbaceous in nature and mainly grow on open and cultivated lands. The bulk of pollen collected came comparatively from few genera. Strong correlation was observed between the intensities of flowering and rainfall. Reproductive swarming and migration occur during high and low intensity of flowering respectively.
- Full Text:
- Date Issued: 2003
Structural studies on some capsular antigens from escherichia coli and klebsiella
- Authors: Anderson, Andrew Nixon
- Date: 1988
- Subjects: Escherichia , Klebsiella , Antigens
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3730 , http://hdl.handle.net/10962/d1001469
- Description: A review of the structural studies of bacterial capsular polysaccharides (K-antigens) from Escherichia coli and Klebsiella, and of the trends in modern chemical and instrumental techniques available for the analysis of carbohydrate material is presented. The structural elucidations of the capsular polysaccharides from E. coli K37 and K55, and Klebsiella K39 are reported with comments on the novelty and possible immunological significance of the structures. The usefulness of the bacteriophage degradation technique has been emphasized using the polysaccharides from E. coli K55, and Klebsiella K30 and K39 to demonstrate the scope of the reaction
- Full Text:
- Date Issued: 1988
The fishes of Tristan Da Cunha and Gough Island (South Atlantic), and the effects of environmental seasonality on the biology of selected species
- Authors: Andrew, Timothy Gilbert
- Date: 1993
- Subjects: Fishes -- Tristan da Cunha Fishes -- Gough Island Fishes -- Conservation
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5284 , http://hdl.handle.net/10962/d1005128
- Description: This study focuses on the taxonomy, biogeography and biological aspects of the fishes of Tristan da Cunha and Gough Island in the cental South Atlantic Ocean. Oceanographic measurements were undertaken to determine the position and nature of the Subtropical Convergence (STC) in the vicinity of the islands. The Tristan da Cunha group is thought to be situated on the northern edge of the STC while Gough Island is situated on the southern edge of the front. The seasonal environmental cycle at the islands is characterised by an annual sea surface temperature fluctuation of approximately 5 °C and an annual change in stratification of the water column. It is suggested that this increase in stratification at the STC, brought about in the summer by insolation warming the surface layers of the ocean, enhances primary production. The STC is identified as a unique habitat for fishes and as an important barrier to dispersal of species in the Southern Ocean. The present study has produced 18 new distributional records from the shelf waters of Tristan da Cunha and Gough Island. The fish fauna known from the shelf waters of these islands is reviewed, and a diagnosis, synonymy, and in some cases an illustration are provided. For certain species, brief notes on their biology, relative abundance and seasonal distribution are included. An analysis of the ichthyofaunal relationships between shallow water areas in the vicinity of the STC has resulted in the identification of a characteristic neritic STC ichthyofauna. The circumglobal distribution of many of these species is thought to be a consequence of a dispersive pelagic phase in their life-cycles. Biological processes in fishes at these islands are temporally and spatially affected by seasonal changes in oceanographic conditions. Seasonal sea temperature variation was identified as being an indicator of other oceanographic phenomena that may affect processes such as growth, reproduction and feeding in fishes at the islands. Most species have a summer spawning season and growth rate increased during the summer months. It was hypothesised that enhanced primary production and a related increase in food quality and availability during the summer were the major factors temporally regulating the growth and reproduction of fishes at the islands. Twenty families of neritic fishes have been recorded in the shelf waters of Tristan da Cunhaand Gough Island. Most families are represented by only one species. Because of this a wide range of life-history strategies are apparent in the fauna. Nevertheless, there are a number of common life-history characteristics shared by most of the neritic species. Firstly, the early lifehistory of many species included an extended pelagic phase which might have facilitated colonisation throughout the STC zone in the past, thereby regulating extant species diversity in this region. Secondly, the common occurrence of an extended summer breeding season and iteroparity suggested that these characters also contributed to survival in what is considered to be an unpredictable environment. It would appear that these common characteristics hold the key to the success of many fishes in the STC zone. This study has contributed to our understanding of oceanic island ecosystems and has revealed distributional patterns of fishes that were unknown previously. By focusing on the biological processes of selected species the regulatory role played by local environmental conditions became apparent. The results of this study are also relevant to proposed conservation measures for Tristan da Cunha and Gough Island.
- Full Text:
- Date Issued: 1993
Lead-radium dating of two deep-water fishes from the southern hemisphere, Patagonian toothfish (Dissostichus eleginoides) and Orange Roughy (Hoplostethus atlanticus)
- Authors: Andrews, Allen Hia
- Date: 2009
- Subjects: Fishes -- Age determination , Fishes -- Southern hemisphere -- Longevity , Fishes -- Growth , Radioactive dating , Patagonian toothfish , Patagonian toothfish -- Fisheries , Orange roughy , Orange roughy -- Fisheries , Deep-sea fishes -- Southern hemisphere , Deep-sea fisheries , Deep-sea fisheries -- Southern hemisphere
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5295 , http://hdl.handle.net/10962/d1005140
- Description: Patagonian toothfish (Dissostichus eleginoides) or "Chilean sea bass" support a valuable and controversial fishery, but the life history is little known and longevity estimates range from ~20 to more than 40 or 50 yr. In this study, lead-radium dating provided validated age estimates from juveniles to older adults, supporting the use of otoliths as accurate indicators of age. The oldest age groups were near 30 yr, which provided support for age estimates exceeding 40 or 50 yr from grow zone counts in otolith sections. Hence, scale reading, which rarely exceeds 20 years, has the potential for age underestimation. Lead-radium dating revealed what may be minor differences in age interpretation between two facilities and findings may provide an age-validated opportunity for the CCAMLR Otolith Network to reassess otolith interpretations. Orange roughy (Hoplostethus atlanticus) support a major deep-sea fishery and stock assessments often depend on age analyses, but lifespan estimates range from ~20 to over 100 yr and validation of growth zone counts remained unresolved. An early application of lead-radium dating supported centenarian ages, but the findings were met with disbelief and some studies have attempted to discredit the technique and the long lifespan. In this study, an improved lead-radium dating technique used smaller samples than previously possible and circumvented assumptions that were previously necessary. Lead-radium dating of otolith cores, the first few years of growth, provided ratios that correlated well with the ingrowth curve. This provided robust support for age estimates from otolith thin sections. Use of radiometric ages as independent age estimates indicated the fish in the oldest group were at least 93 yr. Lead-radium dating has validated a centenarian lifespan for orange roughy. To date, radium-226 has been measured in otoliths of 39 fish species ranging from the northern Pacific and Atlantic Oceans to the Southern Ocean. In total, 367 reliable radium-226 measurements were made in 36 studies since the first lead-radium dating study on fish in 1982. The activity of radium-226 measurements ranged over 3 orders of magnitude (<0.001 to >1.0 dpm.g⁻¹). An analysis revealed ontogenetic differences in radium-226 uptake that may be attributed to changes in habitat or diet. Radiometric age from otolith core studies was used to describe a radium-226 uptake time-series for some species, which revealed interesting patterns over long periods. This synopsis provides information on the uptake of radium-226 to otoliths from an environmental perspective, which can be used as a basis for future studies.
- Full Text:
- Date Issued: 2009
The evolution of the Lepilemuridae-Cheirogaleidae clade
- Authors: Andrews, Curswan Allan
- Date: 2019
- Subjects: Lemurs
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/40216 , vital:35989
- Description: The Lepilemuridae and the Cheirogaleidae, according to recent molecular reconstructions, share a more recent common ancestor than previously thought. Further phylogenetic reconstructions have indicated that body size evolution in this clade was marked by repeated dwarfing events that coincided with changes in the environment. I aimed to investigate the morphological implications of changes in body size within the Lepilemur-cheirogaleid clade, testing four predictions. Together with Dr. Couette, I collected data on the overall palate shape and predicted that shape is likely to be influenced by several factors including phylogeny, body size and diet. Geometric morphometric analyses revealed that, although a strong phylogenetic signal was detected, diet had the major effect on palate shape. In a similar vein, when examining the arterial circulation patterns in these taxa, I predicted that changes in body size would result in changes and possible reductions in arterial size, particularly the internal carotid artery (ICA) and stapedial artery (SA). Analyses with micro-computed tomography (CT) and 3D imaging indicated that changes in body size led to reduction of a functional stapedial artery in Lepilemur, making it an intermediate stage between the daubentoniid, lemurid and indriid species with large stapedial arteries, and the smaller bodied cheirogaleids with an alternative blood supply in the form of an enlarged ascending pharyngeal artery. Lepilemur is the smallest living folivorous primate, and likely to be at the threshold body size to be able to subsist on such a poor diet. To investigate shifts in dietary patterns that accompanied changes in body size, I chose to explore the reported behaviour of caecotrophy as a possible means for the sportive lemurs to derive additional nutrient from their food sources. I predicted that, if caecotrophy is a way to assist folivory at small body size, the energy contained in “caecotrophic” and latrine faecal samples should be different. Analyses showed significant iv differences between the two types of faeces and, combined with an analysis of faecal bacterial diversity, support the occurrence of caecotrophy. Finally, I compared the digestive efficiency of two small, distantly related gummivorous primates that evolved their diets convergently. I studied the digestion of gum in Microcebus griseorufus and compared this with gum digestion in Galago moholi. I predicted that an evolutionary disposition to fermentation inherited from a folivorous ancestor would aid in the digestion of gum in mouse lemurs. Results indicated that retention time was prolonged by the presence of secondary compounds in Microcebus fed with Commiphora gum but relatively shorter (< 24 hrs) when fed Alantsilodenron gum, a preferred food. Despite the fact that G. moholi has an ansa coli, which is missing in M. griseorufus species, both are highly efficient at digesting gum. These data provide some of the first indicators of how dietary changes from a larger-bodied folivorous ancestor to partially gummivorous, small-bodied descendants may have occurred in evolutionary time.
- Full Text:
- Date Issued: 2019
Biodiversity conservation and rural livelihoods across four nature reserves in the Eastern Cape Province, South Africa: Striving towards a balance between livelihoods and conservation
- Authors: Angwenyi, Daniel
- Date: 2020
- Subjects: National parks and reserves -- South Africa -- Eastern Cape , Nature conservation -- South Africa -- Eastern Cape , Biodiversity conservation -- South Africa -- Eastern Cape , Rural population -- South Africa -- Eastern Cape , Sustainable development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/138551 , vital:37649
- Description: The realisation that biodiversity is being lost at alarming rates, and that intact ecosystems are essential for ecological functioning and sustenance of human life, has led to biodiversity taking centre stage in national and international agencies’ environmental talks agendas. Protected areas are viable option to stem biodiversity loss. However, the establishment of protected areas might have negative impacts on communities living adjacent to them, leading to poor relations and frequent conflicts between these communities and the managers of protected areas. The Eastern Cape Province has twenty-one nature reserves and three national parks. Since the province is rural, the assumption was likelihood that households in the province depended on natural resources, specifically non-timber forest products for their day-to-day needs. Therefore, it was hypothesised that conserving natural resources, was likely to negatively impact on the livelihoods of most households adjacent to these areas, which in turn would influence their perceptions towards these resources and eventually the effectiveness of conservation efforts. This study aimed at examining the relationship between biodiversity conservation and rural livelihoods in the Eastern Cape Province, South Africa, focusing on four nature reserves – Tsolwana, Hluleka, Mkambati and Great Fish River. The objectives of the study were to: I I. Compare the vegetation productivity inside and outside, as well as land cover change in four nature reserves, as an indicator of conservation effectiveness. II II. Evaluate the relationship between biodiversity conservation and livelihoods in four nature reserves. III III. Evaluate how people’s expectations of nature reserves and perceptions towards nature reserve influence their support of conservation activities. Four hundred semi-structured questionnaires were administered to household heads of communities living at various distances from the four nature reserves, using a gradient design (based on distance). The motive of using distance was to assess whether livelihood status varied with distance from the nature reserves, since data on livelihood before the reserves’ establishment could not be obtained. Through a questionnaire survey, data on demographic information, livelihood assets, livelihood activities, livelihood strategies, livelihood trends, and impacts of the reserves on local communities were gathered. Focus group interviews were also conducted to complement the household surveys. A chi-square test was used to test if there was a relationship between distance from the reserves’ boundaries and local communities’ state of livelihoods. NVivo was used to analyse qualitative data Themes substantiated using literature. The study finds that the reserves did not have any impact on livelihood assets because most households in the study area did not directly depend on the resources found in the reserves. These households depended mostly on government grants and remittances from relatives working in other areas in the country. The reserves, however, supplied some goods and services to local communities, including meat, jobs, water, building materials, security from wild animals, education, skills development, and recreation. There were also a number of negative impacts associated with the reserves including resource use restrictions, harassment by reserves management, killing of domestic animals, and attacks on humans by wild animals escaping from the reserve. The majority (60%) of locals had substantive knowledge of the reserves’ role because of this awareness, 79% were supportive of reserves. However, there were mixed views by locals on the best way to manage these reserves. The most dominant view was that natural resources should be preserved for future generations, while meeting the current generation’s livelihood needs. Other lesser views included that the reserves’ management should involve locals in the management structures, either as active members or through consultation. Similarly, there were people feeling that the reserve is an obstacle to their livelihoods and should be closed and the land returned to the rightful owners. The vegetation productivity was better inside as compared to the outside the reserves. This activity also improved in the sixteen (16) years under assessment. This imply that the ecological functionality of the reserves is better than the surrounding areas and is improving with time. The research recommended that local communities could be an asset in conservation since most of them were in favour of the reserves. This, however, will need reserve managers to form workable partnerships with these communities, where the rights and responsibilities for both parties are defined. Besides these partnerships, lease agreements between local communities and reserves management to enhance benefits to the communities could encourage local communities to take pride in the natural resources within the reserves. This will ultimately becoming stewards to these resources. Development of tourism infrastructure such as curio shops and convenience stores to enhance livelihood opportunities could also help. For the local communities to be well represented it is important that the committees representing them in the various reserve matters be expanded and democratically elected. Where necessary, community awareness programmes on the importance of the reserves and the roles of local communities should be implemented.
- Full Text:
- Date Issued: 2020
An examination of practices and experiences of teacher educators in the supervision of a national early childhood home based programme
- Authors: Annatolia, Misi
- Date: 2020
- Subjects: Early childhood education -- Zimbabwe
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/49362 , vital:41695
- Description: Zimbabwean teacher educators are, by the nature of their job description, required to supervise student teachers doing teaching practicum for the 0-3 home based programme. However, analysis of supervision reports of the home based programme indicates some inconsistencies in comments made by different supervisors, whereby the descriptors and supervision overall scores do not tally. It seems the supervision of the home based teacher education programme is not being implemented as expected. Hence, the purpose of this qualitative case study was to examine practices and experiences of teacher educators in the supervision of a National Early Childhood Development Home Based Teacher Education Programme (NECDHBTEP). The objective of the study was to address the key question: ‘What are the practices and experiences of teacher educators in the supervision of a NECDHBTEP. In addressing the question, the researcher used supervision as a conceptual framework. The theoretical framework which informed the study was Contextual Supervision (CS) which has its philosophical foundations in constructivism, beneficence and justice. Purposive sampling was employed in the study where two primary teachers’ colleges were selected. From each college, ten teacher educators were selected for semi-structured interviews, two focus group discussions and document analysis on teacher educators’ supervision reports. Triangulation of the data was done so as to enhance its trustworthiness. Three major themes emerged from the study, namely, the influence of home context, experience of supervisors on NECDHBTEP and supervision approaches. The study discovered that the home context, to some extent, influences supervision of the NECDHBTEP. The study also established that teacher educators face multiple challenges when supervising student teachers on the ECD home based programme. The researcher made some recommendations from the findings. One of the recommendations was for colleges to develop a specific supervision instrument for the home based ECD supervision (0-3 years category). Furthermore, there is need for Zimbabwean primary teachers’ colleges to engage in rigorous in-service training for lecturers who are not knowledgeable about the NECDHBTEP.
- Full Text:
- Date Issued: 2020
South African farm wages and working conditions: with special reference to the Albany district, 1957 to 1977
- Authors: Antrobus, Geoffrey Gordon
- Date: 1984
- Subjects: Agricultural wages -- South Africa -- Eastern Cape , Agricultural laborers -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1028 , http://hdl.handle.net/10962/d1003722
- Description: The focus of the study is the wages and working conditions of farm labourers in commercial agriculture. After an outline examination of the broad trends in employment and wages in the agricultural industry as a whole, the emphasis falls on a micro-study of employment practices in the Eastern Cape magisterial district of Albany. The results of a survey of farmers was used to determine the level of wages, including payments in kind, the value of housing, cropping and grazing rights. It was found that cash wages made up only 25% of the total remuneration of R684 per annum, while purchased and farm produced rations made up a further 40% of the total. A survey conducted in the Albany district two decades previously was used to compare the real earnings in 1957 and 1977. Although real cash wages and rations increased over the twenty year period the restriction of cropping and grazing rights had the effect of keeping real earnings static. In the light of the improvement of other working conditions, such as the reduction in working hours, however, it is concluded that some increase in real wages did occur . It is evident that there are no clear-cut recipes for successful farm labour management and no unequivocal statements should be made about the most visible element, namely cash wages.
- Full Text:
- Date Issued: 1984
Removal and recovery of gold and platinum from aqueous solutions utilising the non-viable biomass Asolla filiculoides
- Authors: Antunes, Ana Paula Martins
- Date: 2002
- Subjects: Azolla filiculoides Metal wastes -- Recycling Gold -- Recycling Platinum -- Recycling
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3894 , http://hdl.handle.net/10962/d1003726
- Description: Waste water from the mining industry is generally extremely complex and contains numerous species which influence the adsorption of the metals to any biomass. A variety of factors need to be addressed before treatment is considered viable. It is also beneficial to establish the binding characteristics of the metal of interest to maximise its interaction with the biomass to be utilised. Azalia filiculaides was investigated in the adsorption of gold(III), lead(II), iron(ID), copper(II) and platinum (IV). In batch studies, the optimum biomass and initial gold(III) concentrations were found to be 5 gIL and 8 mgIL respectively. The adsorption of gold(ID) is principally pH-dependent with optimal removal at pH 2. Lead(II), iron(III) and copper(II) did not compete with gold(III) adsorption under equimolar and simulated effluent conditions. Halides, with increasing affinity for gold (chloride < bromide < iodide), can affect gold uptake with the soft base, iodide, exhibiting the most inhibition (25%) and the hard base, chloride, O%. Mercaptoethanol (soft base) showed no interference in gold(III) adsorption while the presence of sulphate (hard base) and sulphite (borderline base) showed that concentrations in excess of 1 0 mM may adversely affect gold(ill) uptake, most likely due to competition for cationic sites on the biomass. Column studies, better suited to high volume treatment, indicated that a flow-rate of 5 mL/min and an initial gold(ill) concentration of 5 mgIL was optimal. Competitive effects between lead, iron, copper and gold again showed little or no interference. The halides, chloride, bromide and iodide, affect gold(ill) uptake similarly to the batch studies, while the bases mercaptoethanol and sulphate minimally affect gold(III) binding with sulphite severely hampering adsorption (70% inhibition). To optimise gold desorption, preliminary batch studies indicated that a ratio of 1:1 of adsorbentdesorbent was optimal, whilst gas purging of thiourea with oxygen, air and nitrogen decreased gold elution in proportion to decreased amounts of oxygen. A series of desorbents were utilised, in column studies, to optimise and determine the speciation of bound gold. The presence of an oxidant with thiourea enhanced desorption greater than 3 fold when compared with thiourea alone. Thiourea desorption studies, aided by the oxidant, suggest that gold is present in the + I and 0 oxidation states. Ultimately thiourea, perchloric acid and hydrochloric acid was found to be the most optimal elutant for gold (J 00% recovery). For selective metal recovery oflead and copper, pre-washing the plant material with water, utilising an acid (0.3 M nitric acid), pumping in an up-flow mode, and recycling the desorbent six times was found to be optimal elutant for gold (J 00% recovery). Cost analysis of utilising elutant versus incinerating the biomass for gold recovery indicated the latter as the most economical. Over a 5 cycle adsorption and desorption series, acid desorption before each adsorption cycle was found to result in greater than 92% desorption for lead and 96% for copper. Gold recovery was 97% with incineration. A preliminary study with gold effluent (Mine C) indicated that nickel and sulphate was removed in batch and column studies. Gold removal was found to be 100% and 4% in batch and column studies respectively. Adsorption of gold in the effluent study was accompanied by the release ofHt. Modifying the plant material with various reagents failed to identify the primary binding sites and the role of polysaccharides, proteins and lipids in gold(ill) uptake. The mode of gold binding is suggested as being initially ionic, this is very rapid, with the interaction of the anionic complex, [AuCI₄]". with the cationic biomass (PH 2). This eventually leads to the displacement of the chloride ligand(s) initiating covalent binding. Spectral studies of the chemical interaction between gold and the representative tannins indicated the protonated hydroxy groups to be responsible. All evidence suggests that the binding mechanisms of gold are not simple. Preliminary adsorption studies of platinum by Azalia filiculaides were conducted. Batch studies indicated that J gIL biomass concentration, initial platinum concentration of 20 mgIL and pH 2 are optimal, while the column studies indicated a flow-rate of! 0 rnL/min and initial platinum concentration of 20 mgIL as optimal. In the platinum effluent study, platinum showed a removal of 23 % and 2 J % for the batch and column studies respectively. Again adsorption was accompanied by //' release. Azalia filiculaides demonstrated its feasibility in the removal of gold and platinum from simulated as well as waste water solutions. Its potential viability as a biosorbent was demonstrated by the high recovery from synthetic solutions of greater than 99% for gold (2-10 mgIL), and greater than 89% for platinum (20 mgIL).
- Full Text:
- Date Issued: 2002
Pyrroloiminoquinone metabolites from South African Latrunculid sponges
- Authors: Antunes, Edith Martins
- Date: 2003
- Subjects: Sponges -- South Africa PQQ (Biochemistry) Marine metabolites -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4340 , http://hdl.handle.net/10962/d1005001
- Description: An in depth chemical investigation of the major and minor pyrroloiminoquinone metabolites produced by four species of endemic South African Latrunculid sponges, collected from Algoa Bay and the Tsitsikamma Marine Reserve off the south eastern coast of South Africa, yielded eleven new and twelve known pyrroloiminoquinone metabolites. The structures of the new metabolites were determined using standard spectroscopic techniques. Tsitsikamma pedunculata was shown to contain 7,8-dehydro-3-dihydro-discorhabdin C (2.1), 14-bromo-7,8-dehydro-3-dihydro-discorhabdin C (2.2), discorhabdin S (2.3), 14-bromo-1-hydroxy-discorhabdin S (2.4), 1-bromo-2-hydroxy-4-debromo-discorhabdin S (2.5), and 2,4-debromo-3-dihydro-discorhabdin C (2.6), together with the known compounds 14-bromo-discorhabdin C (1.51), 14-bromo-3-dihydro-discorhabdin C (1.52) and 3-dihydro-discorhabdin C. The metabolites from T. pedunculata were characterised by the presence of a reduced C-3 carbonyl and bromination at C-14. Compounds isolated from a second Latrunculid sponge, Latrunculia lorii, ranged from a substituted bicyclic pyrrolecarboxylic acid, makaluvic acid A (1.47), to the simple tricyclic known pyrroloiminoquinones makaluvamine C (1.33) and damirone B (1.20) and the more complex discorhabdin D type metabolites, discorhabdin M (3.2), 1-amino discorhabdin D (3.3), 1-methoxy discorhabdin D (3.4) and 1-alanyl discorhabdin D (3.5). Discorhabdin G* (3.1) was also isolated and characterised. This is the first reported occurrence of the known compounds 1.20, 1.33 and 1.47 in a Latrunculia sponge. Discorhabdin and bis-pyrroloiminoquinone type compounds predominated in Tsitsikamma favus. Three known, tsitsikammamines A (1.71) and B (1.72), 1.52, and five new pyrroloiminoquinones, tsitsikammamine N-oxime (4.1), tsitsikammamine B N-oxime (4.2), 2.1, 2.4 and 2.6, were isolated from this sponge. A fourth Latrunculid sponge (Strongylodesma sp.) yielded three known compounds, discorhabdins A (1.57), D (1.61) and 1.53, and one new pyrroloiminoquinone 3.3. The dual role of these metabolites as cytotoxic agents and pigments resulted in an attempt to relate the photochemical properties of these metabolites to their cytotoxicity. The pyrroloiminoquinone metabolites studied exhibited moderate singlet oxygen quantum yields, while three compounds (1.57, 4.1 and 4.2) were shown to be capable of producing radicals at a wavelength of 532 nm. The possibility of a correlation between the electrochemical properties and anti-cancer (HCT-116) activity of selected pyrroloiminoquinones was explored. A study of the oesophageal and ovarian cytotoxicities of two pyrroloiminoquinones (1.57 and 1.72), together with an investigation into the intercalation and topoisomerase I inhibitory activity of the bis-pyrroloiminoquinones (1.71, 1.72, 4.1 and 4.2), are presented.
- Full Text:
- Date Issued: 2003
The sustainability of South African construction small, medium and micro enterprises
- Authors: Anugwo, Iruka Chijindu
- Date: 2017
- Subjects: Construction industry -- South Africa -- Port Elizabeth Sustainable development -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/15259 , vital:28194
- Description: The construction industry is one of the strategic sectors that drive the economic sustainability and competitiveness of any nation. However, the chronic business failure amongst the start-ups and Small, Medium and Micro Enterprises (SMMEs) in the construction industry globally is of great concern to economic prosperity for both developed and developing countries. This challenge is significantly high in the South African construction industry, where SMMEs account for 95% of the business entities, of which about 80% are most likely to exit from the market within their first five years of operation. Previous studies in this field centred on the factors that lead to construction-business failure. However, the actual operational elements of surviving SMMEs have rarely been addressed and are little understood. Thus, this research aimed to explore the strategic drivers that offer significant solutions to the challenges facing start-up contractors in the South African construction industry. The review of the related literature revealed the strategic drivers and business survival characteristics that foster SMME economic sustainability and competitiveness in the construction market. The qualitative research approach that is rooted in the phenomenological paradigm was adopted for this study. Port Elizabeth, located in the Eastern Cape Province of South Africa was the selected geographical scope for this research. Thirty-four (34) construction organisations were purposively selected from the Port Elizabeth construction industry development board (cidb) register of contractors in grades 4-6. The purposive sampling technique was adopted in selecting respondents based on the snowball approach. The research data were collected through in-depth interviewing. It was found that the SMME contractors who succeeded in their first 5 years of operation possessed the following qualities: “fundamental educational qualifications”; “experience and knowledge of construction works”; “a clear understanding of competitive business strategies and characteristics”; “critical skills and multi-skills (functional project teams)”; and “rely on strategic resources, competencies and capabilities”. Also, the significant factors contributing to the SMME contractors’ competitiveness were: “entrepreneurship skills”; “innovation and technological skills”; “leadership skills”; “education, skills training, and investment in Research and Development (R&D)”; as well as “strategic-alliance advantage”. Moreover, globalisation and internationalisation, and government support have significant potential to impact on the success and sustainability of SMME contractors. Unfortunately, these factors are under-utilised or un-strategically adopted by most of the South African SMME contractors. The research has also developed a conceptual model for sustainable performance of SMMEs based on the results and informed by the theoretical framework. The research has also developed a business-survival strategy and model for SMME contractors in the South African construction industry. The study has achieved its aim of identifying the strategic business practices, models and concepts that the surviving and active SMME contractors employed to thrive within and beyond the first five years in the industry. Based on these findings, the study recommends that the start-ups and SMME contractors should gain an insightful and strategic business knowledge on how to develop and grow a competitive and economically sustainable organisation in the industry. This should form part of their competitive business strategic models, their business review plans; and set the benchmark for performance evaluation.
- Full Text:
- Date Issued: 2017
The intersection between social development and the internationalisation of higher education in Colombia
- Authors: Anzola-Pardo, Giovanni
- Date: 2018
- Subjects: Education, Higher -- Colombia , Education and globalization International education -- Colombia Education, Higher -- International cooperation -- Colombia
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/23371 , vital:30536
- Description: The study addresses the nature of Colombian sustainable social development and the internationalisation of higher education (iHE). This intersection is analysed within various theoretical paradigms surrounding social sustainable development and the internationalisation of higher education. This study aims at reviewing the activities of Higher Education Institutions (HEIs) which focus on internationalisation. The analysis focuses on the manner in which HEIs in Colombia approach internationalisation vis-à-vis social sustainable development, and emphasis is made on knowledge transfer, research and community engagement. Using the theories of sustainable development, the iHE, in terms of practises and policies, are assessed. Within a mixed-methods approach, data gathered from Colombian university heads (16 presidents and vice-presidents) and 133 individuals responsible for internationalisation affairs is analysed. Concurrent triangulation is used to help introduce a series of themes and sub-themes derived from the qualitative and quantitative information. Within a social constructionist framework, this study has a twofold purpose. On the one hand, it is sought to identify and understand the challenges for Colombia’s academic internationalisation; on the other, an in-depth approach is presented in relation to the way different stakeholders perceive the society-HE internationalisation nexus. The major findings of the study indicate that there is a need to clarify and revise Colombia’s Higher Education policy to address both the education needs of the society and its social development requirements. It was also found that higher education internationalisation could act as an important agent of social change.
- Full Text:
- Date Issued: 2018
Evaluation of antidiarrhoeal and toxicological properties of Hermannia Incana cav.: a South African medicinal plant
- Authors: Appidi, Jaipal Reddy
- Date: 2010
- Subjects: Sterculiaceae , Medicinal plants -- South Africa -- Eastern Cape , Diarrhea , Botany, Medical
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:11304 , http://hdl.handle.net/10353/259 , Sterculiaceae , Medicinal plants -- South Africa -- Eastern Cape , Diarrhea , Botany, Medical
- Description: Hermannia incana Cav. (Sterculiaceae), known as sweet yellow bells, is a medicinal plant used by the people of the Eastern Cape for the treatment of stomach-ache and diarrhoea. It has purgative and diaphoretic effects. It is a prostrate herb with yellow flowers and sparsely hairy and slightly glandular leaves, occurring in grassland and marshes in the Eastern Cape Province of South Africa. Based on the ethnomedical uses of this plant, the research project was designed to evaluate its antidiarrhoeal and toxicological properties. An ethnobotanical study of plants used for the treatment of diarrhoea in the Eastern Cape Province was carried out, using a questionnaire which was administered to herbalists, traditional healers and rural dwellers. This survey indicated a total of 17 plant species from 14 families. Elephantorrhiza elephantine (Burch.) Skeels, Hermannia incana Cav., Pelargonium reniforme Curt., Alepidea amatymbica Eckl. & Zeyh. and Bulbine latifolia (L.f.) Roem. et Schult. were the most frequently mentioned and highly recommended plants for the treatment of diarrhoea by both the traditional healers and rural dwellers. The root, bark and leaves are the common parts of plants used, while decoctions and infusions are the main methods of preparation. The agar dilution method was used to study the antimicrobial activity. The methanol extracts of the plant showed appreciable activity against Gram-positive and Gram-negative bacteria at concentrations ranging from 0.5 to 7.0 mg/ml. The acetone and water extracts of both the leaves and the roots showed moderate activity against Gram positive bacteria and less activity against Gram negative bacteria. All the extracts inhibited the growth of the fungi Aspergillus flavus, Aspergillus niger, and Mucor hiemalis with growth inhibition ranging from 54.31 percent to 96.67 percent at 0.1-10 mg/ml. None of the extracts suppressed the growth of Candida albicans at the maximum concentration (10 mg/ml) tested. iii In the in vivo antidiarrhoeal evaluation using Wistar rats, the aqueous extract at all the doses tested, significantly prolonged the time of induction of diarrhoea and also reduced the frequency of diarrhoeal episodes and fecal parameters (total number, number of wet, fresh and dry weight and water content of the faeces). The percentage inhibition of defecation and intestinal content (enteropooling) were increased in dose dependent manner. The doses also reduced the intestinal transit time of charcoal, masses and volumes of intestinal fluid (gastrointestinal motility). These results are indications of antidiarrhoeal property of H. incana leaf extract with the 600 mg/kg body weight of the extract being the most effective. In the toxicological evaluation using Wistar rats, the oral administration of the extract did not produce any significant effect on the liver and kidney body weight ratios, RBC, HB, PCV, MCV MCH, MCHC, RCDW, WBC, neutrophils, monocytes and basophils cholesterol, triacylglycerol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol and atherogenic index. The extract also did not affect the levels of sodium, potassium, chloride, inorganic phosphorus, urea, creatinine, total protein, globulin, albumin, total and conjugated bilirubin. The activities of alkaline phosphatase, gamma glutamyl transferase and alanine aminotransaminase in the serum were increased by the extract whereas aspartate aminotransaminase was decreased. The levels of LUC, platelets, lymphocytes and eosinophils were significantly affected at 600 mg/kg body weight. The available evidence in this study suggests that the extract of H. incana leaf is mild, parameter and dose specific. The structure and distribution of foliar appendages on the leaves of this plant were investigated with the JEOL (JSM-6390LV) scanning electron microscope (SEM). Both glandular and non-glandular trichomes were observed. Long stalked glandular trichomes were present on both the abaxial and adaxial surfaces while short stalked glandular trichomes were present only on the adaxial surface. Glandular trichomes were capitate while nonglandular trichomes were stellate with many arms. Energy dispersive X-ray spectroscopyiv SEM showed that Al, Ca, K, Na, Ti and Si were the major constituents of the crystals analyzed from the leaf surfaces. The phytochemical screening of H. incana revealed the presence of bioactive antidiarrhoeal agents such as alkaloids, tannins, saponins, phenolics, triterpenes, cardiac glycosides, flavonoids, cardenolides and dienolides. Two flavonoids, epicatechin and 3, 5, 7, 2’ tetra-hydroxy flavone-3- O--D-glucopyranoside were isolated from the leaves of the plant through bio-active guided fractionation. Both these compounds were screened against diarrhoea causative organisms (Echerichia coli, Shigella flexneri, Bacillus cereus and Staphylococcus aureus) and exhibiting minimum inhibitory concentrations ranging from 12.5 to 100 μg/ml. The findings from this research have generally justified the traditional use of this plant for the treatment of diarrhoea in this province.
- Full Text:
- Date Issued: 2010