12 research outputs found

    Metals and the conformation of fibrin

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    The carboxy terminal of the γ-chain of human fibrinogen contains at least three biologically. important functional domains: (i) the fibrinogen γ-chain polymerisation centre, (ii) the platelet receptor domain and (iii) the site for staphyloccocal clumping. The nature of the site specificity of these interactions necessitates the existence of a preferred conformation for this region, the nature of which has yet to be clearly established. A novel zinc metalloproteinase isolated from puff adder venom (PAV protease) capable of specifically cleaving the di-γ-chain of transglutaminase (Factor XIIIa) catalysed crosslinked plasmin derived D-dimer into apparently symmetrical monomers has been described. The activity is fibrin specific and displays an unusual site specificity for the γ-carboxy terminal domains within the crosslink region. The activity was reported to be potentiated by zinc. The effect of zinc on the digestion of D-dimer by PAV protease was evaluated by SDS-PAGE and by a fluorimetric technique utilising a fluorescent dansylcadaverine conjugate of the substrate (f-D-dimer). A differential zinc binding study determined that the potentiation of activity by zinc was due to a zinc-substrate rather than a zinc-enzyme interaction. The binding constant for zinc to D-dimer was determined by Scatchard analysis of zinc titration data. The interaction of zinc and f-D-dimer was confirmed by fluorescence anisotropy determinations. The nature of the coordination capsule around the metal cation was determined by examining a cobalt-fibrin-D-dimer complex and characterising the difference visible absorption spectrum thereof. The donor ligands from the D-dimer fragment for the metal ion were determined as histidines by examining zinc(II) and cobalt(II) binding to diethylpyrocarbonate modified fibrin-D-dimer and hydroxylamine treated DEPC-fibrin-D-dimer. Through this study it has been established that the PAV protease cleavage of the di-γ-chain of the plasmin derived D-dimer fragment is potentiated by zinc(II) ions through the formation of a novel zinc determined conformation of fibrin-D-dimer. This presents the possibility of a fibrinspecific neo-epitope being manifested in the presence of zinc ions that could provide a means to determine fibrin degradation products more specifically. A model for the neo-epitope has been proposed

    A scientometric examination of the performance of water research in South Africa

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    Regular assessment of the state of water research and development (R&D) in South Africa is a necessary component of science policy and successful R&D implementation. Among others, effective R&D has a direct impact on water resource management and promotes training and capacity building initiatives. Much of the country’s water research is carried out under the auspices of the Water Research Commission (WRC), a national public entity established by the Water Research Act (Act No. 34 of 1971). Water R&D is carried out by universities, public research institutions and science councils as well as the private sector. A scientometric examination of South Africa’s research and development performance indicates that while the water research and development community is small, it is highly productive. The analysis indicates that the South African contribution to the global share of water-related papers in journals indexed by the ISI (now Thomson Reuters Web of Science) is more than 3 times the average for all disciplines in the country, and that South Africa ranks 19th in the world in the domain of ‘Water Resources’. A study of the patent data further indicates a much higher than average conversion of knowledge to products as indicated by the water-related patent/total patent ratios.http://www.wrc.org.zaam201

    Migration under Climate Change in Southern Africa: A Nexus Planning Perspective

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    Population increase is exacerbating resource insecurities due to increased demand for already depleted resources. Coupled with climate change, they are the main drivers of both intra-(rural-urban and urban-urban) and inter-migration (from one country to the other). We carried out a systematic review of literature, focusing on available options to ensure water and food security, as well as improve the socio-economic environment, highlighting the drivers of migration in southern Africa. The aim was to develop informed adaptation strategies and build resilience in the advent of accelerated migration. We developed a migration conceptual framework based on the nexus between water, food and socio-economic interlinkages. Urban areas in southern Africa are under immense pressure to accommodate climate refugees from resource stressed rural areas, a situation that is impacting on agricultural production. Most urban areas are exceeding their ecological thresholds to support the built environment, causing some socio-ecological challenges. Nexus planning can inform adaptation planning on permissible migration that are aligned with regional goals such as regional integration, poverty reduction and improved livelihoods. This would also contribute to the region's achievements of the Sustainable Development Goals. Furthermore, through the identification of synergies and trade-offs, nexus planning can inform regional adaptation strategies for positively managing migration leading to sustainable outcomes

    Climate Change Adaptation through the Water-Energy-Food Nexus in Southern Africa.

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    Climate change is a complex and cross-cutting problem that needs an integrated and transformative systems approach to respond to the challenge. Current sectoral approaches to climate change adaptation initiatives often create imbalances and retard sustainable development. Regional and international literature on climate change adaptation opportunities and challenges applicable to southern Africa from a water-energy-food (WEF) nexus perspective was reviewed. Specifically, this review highlights climate change impacts on water, energy, and food resources in southern Africa, while exploring mitigation and adaptation opportunities. The review further recommends strategies to develop cross-sectoral sustainable measures aimed at building resilient communities. Regional WEF nexus related institutions and legal frameworks were also reviewed to relate the WEF nexus to policy. Southern Africa is witnessing an increased frequency and intensity in climate change-associated extreme weather events, causing water, food, and energy insecurity. A projected reduction of 20% in annual rainfall by 2080 in southern Africa will only increase the regional socio-economic challenges. This is exacerbating regional resource scarcities and vulnerabilities. It will also have direct and indirect impacts on nutrition, human well-being, and health. Reduced agricultural production, lack of access to clean water, sanitation, and clean, sustainable energy are the major areas of concern. The region is already experiencing an upsurge of vector borne diseases (malaria and dengue fever), and water and food-borne diseases (cholera and diarrhoea). What is clear is that climate change impacts are cross-sectoral and multidimensional, and therefore require cross-sectoral mitigation and adaptation approaches. In this regard, a well-coordinated and integrated WEF nexus approach offers opportunities to build resilient systems, harmonise interventions, and mitigate trade-offs and hence improve sustainability. This would be achieved through greater resource mobilisation and coordination, policy convergence across sectors, and targeting nexus points in the landscape. The WEF nexus approach has potential to increase the resilience of marginalised communities in southern Africa by contributing towards attaining the Sustainable Development Goals (SDGs 1, 2, 3, 6, 7, and 13)

    Assessing Progress towards Sustainable Development Goals through Nexus Planning

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    Sustainable Development Goals (SDGs) acknowledge the inter-linkages between human wellbeing, economic prosperity, and a healthy environment and, hence, are associated with a wide range of topical issues that include the securities of water, energy and food resources, poverty eradication, economic development, climate change, health, among others. As SDGs are assessed through targets to be achieved by 2030 and monitored through measurable indicators, this study applied the nexus planning model to monitor and evaluate progress towards SDGs using South Africa as a case study. The study highlighted pathways to ensure socio-ecological sustainability and environmental health by establishing the connectivity between SDGs and nexus approaches. The linkages between SDGs and nexus planning facilitated the sustainable management of resources in an integrated manner. They addressed the cross-sectoral synergies, value-addition, and trade-offs within interlinked sectors. The connectedness of current challenges facing humankind (climate change, rapid urbanisation, migration, and the emergence of novel infectious diseases) require transformative approaches that address these cross-cutting challenges holistically. Managing the intricate relationships between distinct but interconnected sectors through nexus planning has provided decision support tools to formulate coherent strategies that drive resilience and sustainability. The established linkages between nexus planning and SDGs have strengthened cross-sectoral collaboration and unpacked measures for cooperative governance and management through evidence-based interventions. As food production, water provision, and energy accessibility are the major socio-economic and environmental issues currently attracting global attention; the methodology promotes attaining sustainability by 2030

    Urban nexus and transformative pathways towards resilient cities: A case of the Gauteng City-Region, South Africa.

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    Challenges emanating from rapid urbanisation require innovative strategies to transform cities into global climate action and adaptation centres. We provide an analysis of the impacts of rapid urbanisation in the Gauteng City-Region, South Africa, highlighting major challenges related to (i) land use management, (ii) service delivery (water, energy, food, and waste and sanitation), and (iii) social cohesion. Geospatial techniques were used to assess spatio-temporal changes in the urban landscapes, including variations in land surface temperatures. Massive impervious surfaces, rising temperatures, flooding and heatwaves are exacerbating the challenges associated with rapid urbanisation. An outline of the response pathways towards sustainable and resilient cities is given as a lens to formulate informed and coherent adaptation urban planning strategies. The assessment facilitated developing a contextualised conceptual framework, focusing on demographic, climatic, and environmental changes, and the risks associated with rapid urbanisation. If not well managed in an integrated manner, rapid urbanisation poses a huge environmental and human health risk and could retard progress towards sustainable cities by 2030. Nexus planning provides the lens and basis to achieve urban resilience, by integrating complex, but interlinked sectors, by considering both ecological and built infrastructures, in a balanced manner, as key to resilience and adaptation strategies

    The Water-Energy-Food Nexus as a Tool to Transform Rural Livelihoods and Well-Being in Southern Africa.

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    About 60% of southern Africa's population lives in rural areas with limited access to basic services and amenities such as clean and safe water, affordable and clean energy, and balanced and nutritious diets. Resource scarcity has direct and indirect impacts on nutrition, human health, and well-being of mostly poor rural communities. Climate change impacts in the region are manifesting through low crop yields, upsurge of vector borne diseases (malaria and dengue fever), and water and food-borne diseases (cholera and diarrhoea). This study applied a water-energy-food (WEF) nexus analytical livelihoods model with complex systems understanding to assess rural livelihoods, health, and well-being in southern Africa, recommending tailor-made adaptation strategies for the region aimed at building resilient rural communities. The WEF nexus is a decision support tool that improves rural livelihoods through integrated resource distribution, planning, and management, and ensures inclusive socio-economic transformation and development, and addresses related sustainable development goals, particularly goals 2, 3, 6 and 7. The integrated WEF nexus index for the region was calculated at 0.145, which is marginally sustainable, and indicating the region's exposure to vulnerabilities, and reveals a major reason why the region fails to meet its developmental targets. The integrated relationship among WEF resources in southern Africa shows an imbalance and uneven resource allocation, utilisation and distribution, which normally results from a 'siloed' approach in resource management. The WEF nexus provides better adaptation options, as it guides decision making processes by identifying priority areas needing intervention, enhancing synergies, and minimising trade-offs necessary for resilient rural communities. Our results identified (i) the trade-offs and unintended negative consequences for poor rural households' livelihoods of current silo approaches, (ii) mechanisms for sustainably enhancing household water, energy and food security, whilst (iii) providing direction for achieving SDGs 2, 3, 6 and 7

    The Technology Innovation Agency (TIA) : A public support mechanism for technological innovation in a developing country

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    South Africa has since the dawn of democracy progressively built the science and research support components of the National System of Innovation (SANSI) with consistency. At national government level, science and technology developed from being a branch in the Ministry of Arts, Culture, Science and Technology in 1994, to a fully fledged Ministry ten years later. Investments were initially heavier in developing a sustainable research support system with encouraging results. A more recent set of reviews of progress with the development of the SANSI, including a comprehensive OEeD review, has catalyzed the development of a public sector irulOvation support system, the core of which is a new agency - the Technology Innovation Agency (TIA). The TIA has been established through the Technology Innovation Agency Act, as a public entity that will function as a key structural intervention to support government in stimulating and intensifying technological innovation and thereby enhance the country's capacity for local innovation and lessen dependence on imported know-how

    Africa's STI Multilateral Platforms and the Impact on National Science and Innovation Policy

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    Atlanta Conference on Science and Innovation Policy 2009This presentation was part of the session : Achieving National and Global GoalsExamining the impact of the development of continental and regional multilateral S&T platforms on the development of national systems of innovation and bilateral collaboration

    Migration under Climate Change in Southern Africa: A Nexus Planning Perspective

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    Population increase is exacerbating resource insecurities due to increased demand for already depleted resources. Coupled with climate change, they are the main drivers of both intra- (rural-urban and urban-urban) and inter-migration (from one country to the other). We carried out a systematic review of literature, focusing on available options to ensure water and food security, as well as improve the socio-economic environment, highlighting the drivers of migration in southern Africa. The aim was to develop informed adaptation strategies and build resilience in the advent of accelerated migration. We developed a migration conceptual framework based on the nexus between water, food and socio-economic interlinkages. Urban areas in southern Africa are under immense pressure to accommodate climate refugees from resource stressed rural areas, a situation that is impacting on agricultural production. Most urban areas are exceeding their ecological thresholds to support the built environment, causing some socio-ecological challenges. Nexus planning can inform adaptation planning on permissible migration that are aligned with regional goals such as regional integration, poverty reduction and improved livelihoods. This would also contribute to the region’s achievements of the Sustainable Development Goals. Furthermore, through the identification of synergies and trade-offs, nexus planning can inform regional adaptation strategies for positively managing migration leading to sustainable outcomes
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