2OS
- Authors: Machanick, Philip
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/439214 , vital:73556 , https://homes.cs.ru.ac.za/philip/Courses/CS2-OS/Cs2ToOS.pdf
- Description: In this book I approach the problem of understanding an OS from the point of view of a C programmer who needs to understand enough of how an OS works to program efficiently and avoid traps and pitfalls arising from not understanding what is happening underneath you. If you have a deep understanding of the memory system, you will not program in a style that loses significant performance by breaking the assumptions of the OS designer. If you have an understanding of how IO works, you can make good use of OS services. As you work through this book you will see other examples.
- Full Text:
- Authors: Machanick, Philip
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/439214 , vital:73556 , https://homes.cs.ru.ac.za/philip/Courses/CS2-OS/Cs2ToOS.pdf
- Description: In this book I approach the problem of understanding an OS from the point of view of a C programmer who needs to understand enough of how an OS works to program efficiently and avoid traps and pitfalls arising from not understanding what is happening underneath you. If you have a deep understanding of the memory system, you will not program in a style that loses significant performance by breaking the assumptions of the OS designer. If you have an understanding of how IO works, you can make good use of OS services. As you work through this book you will see other examples.
- Full Text:
A chiral hemiporphyrazine derivative
- Wu, Yanping, Gai, Lizhi, Xiao, Xuqiong, Lu, Hua, Li, Zhifang, Mack, John, Harris, Jessica, Nyokong, Tebello, Shen, Zhen
- Authors: Wu, Yanping , Gai, Lizhi , Xiao, Xuqiong , Lu, Hua , Li, Zhifang , Mack, John , Harris, Jessica , Nyokong, Tebello , Shen, Zhen
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/240404 , vital:50831 , xlink:href="https://doi.org/10.1002/asia.201600754"
- Description: The synthesis of an optically active hemiporphyrazine with chiral binaphthyl substituents (1) is reported, providing the first example of the incorporation of an intrinsically chiral moiety into the macrocyclic core of a hemiporphyrazine analogue. A negative circular dichroism (CD) signal is observed in the 325–450 nm region of the CD spectrum of (S,S)-1, while mainly positive bands are observed in the 220–325 nm region. Mirror symmetry is observed across the entire wavelength range of the CD spectra of (R,R)-1 and (S,S)-1. An irreversible one-electron oxidation wave with an onset potential at 1.07 V is observed by cyclic voltammetry, along with a reversible one-electron reduction wave at −0.85 V. Density functional calculations reproduce the experimentally observed data and trends, and provide further insight into the nature of the electronic transitions.
- Full Text:
- Authors: Wu, Yanping , Gai, Lizhi , Xiao, Xuqiong , Lu, Hua , Li, Zhifang , Mack, John , Harris, Jessica , Nyokong, Tebello , Shen, Zhen
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/240404 , vital:50831 , xlink:href="https://doi.org/10.1002/asia.201600754"
- Description: The synthesis of an optically active hemiporphyrazine with chiral binaphthyl substituents (1) is reported, providing the first example of the incorporation of an intrinsically chiral moiety into the macrocyclic core of a hemiporphyrazine analogue. A negative circular dichroism (CD) signal is observed in the 325–450 nm region of the CD spectrum of (S,S)-1, while mainly positive bands are observed in the 220–325 nm region. Mirror symmetry is observed across the entire wavelength range of the CD spectra of (R,R)-1 and (S,S)-1. An irreversible one-electron oxidation wave with an onset potential at 1.07 V is observed by cyclic voltammetry, along with a reversible one-electron reduction wave at −0.85 V. Density functional calculations reproduce the experimentally observed data and trends, and provide further insight into the nature of the electronic transitions.
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A comparative physicochemical study of unsymmetrical indium phthalocyanines in the presence of magnetic nanoparticles or quantum dots
- Osifeko, Olawale L, Nyokong, Tebello
- Authors: Osifeko, Olawale L , Nyokong, Tebello
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/188743 , vital:44781 , xlink:href="https://doi.org/10.1080/00958972.2016.1152628"
- Description: Asymmetric indium phthalocyanine (3, containing an NH2 group) was conjugated (via an amide bond) to magnetic nanoparticle (MNP) functionalized with carboxylic acid or glutathione-capped CdTe/ZnSe/ZnO quantum dots to form 3-MNPs or 3-QDs. Techniques such as time-resolved fluorescence measurements, transmission electron microscopy, XPS, elemental analysis, FTIR, NMR (1H, 13C, and cozy), electronic spectroscopy, as well as mass spectroscopy were employed to characterize 3 and its nanoconjugates. The phthalocyanine conjugated to quantum dot (3-QDs) possesses the lowest Фpd higher Ф∆ and ФT as well as longer triplet lifetimes compares to 3-MNPs and free phthalocyanine.
- Full Text:
- Authors: Osifeko, Olawale L , Nyokong, Tebello
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/188743 , vital:44781 , xlink:href="https://doi.org/10.1080/00958972.2016.1152628"
- Description: Asymmetric indium phthalocyanine (3, containing an NH2 group) was conjugated (via an amide bond) to magnetic nanoparticle (MNP) functionalized with carboxylic acid or glutathione-capped CdTe/ZnSe/ZnO quantum dots to form 3-MNPs or 3-QDs. Techniques such as time-resolved fluorescence measurements, transmission electron microscopy, XPS, elemental analysis, FTIR, NMR (1H, 13C, and cozy), electronic spectroscopy, as well as mass spectroscopy were employed to characterize 3 and its nanoconjugates. The phthalocyanine conjugated to quantum dot (3-QDs) possesses the lowest Фpd higher Ф∆ and ФT as well as longer triplet lifetimes compares to 3-MNPs and free phthalocyanine.
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A critical appraisal of the ideology of monogamys influence on HIV epidemiology
- Kenyon, Chris R, Colebunders, Robert, Dlamini, Sipho S, Meulemans, Herman, Zondo, Sizwe
- Authors: Kenyon, Chris R , Colebunders, Robert , Dlamini, Sipho S , Meulemans, Herman , Zondo, Sizwe
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/450541 , vital:74959 , xlink:href="10.12688/f1000research.14951.2"
- Description: The linked ideas that all members of society should only engage in monogamous relationships and that these should all be based on romantic love are decided outliers from a historical perspective. Despite this, there is a widespread contemporary belief that monogamy based on love is the most ethical and natural form of partnering for humans mononormativism. It has long been accepted that our values influence how we frame and interpret scientific questions. In the article we ask, using the example of mononormativism, how does an individual s sexual ethics influence how they pursue HIV epidemiology? Using a Social Intuitionalist theoretical framework, we argue that a be-lief in monogamy-as-normative has contributed to certain researchers dismissing the evidence that the generalized HIV epidemics in parts of Africa are due to higher rates of non-monogamy.
- Full Text:
- Authors: Kenyon, Chris R , Colebunders, Robert , Dlamini, Sipho S , Meulemans, Herman , Zondo, Sizwe
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/450541 , vital:74959 , xlink:href="10.12688/f1000research.14951.2"
- Description: The linked ideas that all members of society should only engage in monogamous relationships and that these should all be based on romantic love are decided outliers from a historical perspective. Despite this, there is a widespread contemporary belief that monogamy based on love is the most ethical and natural form of partnering for humans mononormativism. It has long been accepted that our values influence how we frame and interpret scientific questions. In the article we ask, using the example of mononormativism, how does an individual s sexual ethics influence how they pursue HIV epidemiology? Using a Social Intuitionalist theoretical framework, we argue that a be-lief in monogamy-as-normative has contributed to certain researchers dismissing the evidence that the generalized HIV epidemics in parts of Africa are due to higher rates of non-monogamy.
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Acoustic biosensors
- Fogel, Ronen, Limson, Janice L, Seshia, Ashwin A
- Authors: Fogel, Ronen , Limson, Janice L , Seshia, Ashwin A
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/431648 , vital:72793 , xlink:href="https://doi.org/10.1042/EBC20150011"
- Description: Resonant and acoustic wave devices have been researched for several decades for application in the gravimetric sensing of a variety of biological and chemical analytes. These devices operate by coupling the measurand (e.g. analyte adsorption) as a modulation in the physical properties of the acoustic wave (e.g. resonant frequency, acoustic velocity, dissipation) that can then be correlated with the amount of adsorbed analyte. These devices can also be miniaturized with advantages in terms of cost, size and scalability, as well as potential additional features including integration with microfluidics and electronics, scaled sensitivities associated with smaller dimensions and higher operational frequencies, the ability to multiplex detection across arrays of hundreds of devices embedded in a single chip, increased throughput and the ability to interrogate a wider range of modes including within the same device. Additionally, device fabrication is often compatible with semiconductor volume batch manufacturing techniques enabling cost scalability and a high degree of precision and reproducibility in the manufacturing process. Integration with microfluidics handling also enables suitable sample pre-processing/separation/purification/amplification steps that could improve selectivity and the overall signal-to-noise ratio. Three device types are reviewed here: (i) bulk acoustic wave sensors, (ii) surface acoustic wave sensors, and (iii) micro/nano-electromechanical system (MEMS/NEMS) sensors.
- Full Text:
- Authors: Fogel, Ronen , Limson, Janice L , Seshia, Ashwin A
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/431648 , vital:72793 , xlink:href="https://doi.org/10.1042/EBC20150011"
- Description: Resonant and acoustic wave devices have been researched for several decades for application in the gravimetric sensing of a variety of biological and chemical analytes. These devices operate by coupling the measurand (e.g. analyte adsorption) as a modulation in the physical properties of the acoustic wave (e.g. resonant frequency, acoustic velocity, dissipation) that can then be correlated with the amount of adsorbed analyte. These devices can also be miniaturized with advantages in terms of cost, size and scalability, as well as potential additional features including integration with microfluidics and electronics, scaled sensitivities associated with smaller dimensions and higher operational frequencies, the ability to multiplex detection across arrays of hundreds of devices embedded in a single chip, increased throughput and the ability to interrogate a wider range of modes including within the same device. Additionally, device fabrication is often compatible with semiconductor volume batch manufacturing techniques enabling cost scalability and a high degree of precision and reproducibility in the manufacturing process. Integration with microfluidics handling also enables suitable sample pre-processing/separation/purification/amplification steps that could improve selectivity and the overall signal-to-noise ratio. Three device types are reviewed here: (i) bulk acoustic wave sensors, (ii) surface acoustic wave sensors, and (iii) micro/nano-electromechanical system (MEMS/NEMS) sensors.
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Agentive learning for sustainability and equity: Communities, cooperatives and social movements as emerging foci of the learning sciences
- Engeström, Yrjö, Sannino, Annalisa, Bal, Aydin, Lotz-Sisitka, Heila, Pesanayi, Tichaona, Chikunda, Charles, Lesama, Manoel F, Picinatto, Antonio C, Querol, Marco P, Lee, Yew J
- Authors: Engeström, Yrjö , Sannino, Annalisa , Bal, Aydin , Lotz-Sisitka, Heila , Pesanayi, Tichaona , Chikunda, Charles , Lesama, Manoel F , Picinatto, Antonio C , Querol, Marco P , Lee, Yew J
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , symposium
- Identifier: http://hdl.handle.net/10962/436670 , vital:73292 , ISBN 978-1-4312-0852-4 , https://repository.isls.org//handle/1/372
- Description: This symposium expands the object and scope of the learning sciences by introducing communities, cooperatives and social movements as crucially important sites of learning. The sym-posium papers employ and critically interrogate cultural-historical activity theory, specifically the theory of expansive learning, and the emerging methodology of formative interven-tions as a potential framework for dealing with learning in communities, cooperatives and social movements. Expansive learning emerges as a process of revitalizing the commons, or commoning. The contributions of the symposium point toward the importance of analyzing and fostering transformative agency as a quality of learning.
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- Authors: Engeström, Yrjö , Sannino, Annalisa , Bal, Aydin , Lotz-Sisitka, Heila , Pesanayi, Tichaona , Chikunda, Charles , Lesama, Manoel F , Picinatto, Antonio C , Querol, Marco P , Lee, Yew J
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , symposium
- Identifier: http://hdl.handle.net/10962/436670 , vital:73292 , ISBN 978-1-4312-0852-4 , https://repository.isls.org//handle/1/372
- Description: This symposium expands the object and scope of the learning sciences by introducing communities, cooperatives and social movements as crucially important sites of learning. The sym-posium papers employ and critically interrogate cultural-historical activity theory, specifically the theory of expansive learning, and the emerging methodology of formative interven-tions as a potential framework for dealing with learning in communities, cooperatives and social movements. Expansive learning emerges as a process of revitalizing the commons, or commoning. The contributions of the symposium point toward the importance of analyzing and fostering transformative agency as a quality of learning.
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Aggregation control of robust water-soluble zinc (II) phthalocyanine-based photosensitizers
- Ikeuchi, Takuro, Mack, John, Nyokong, Tebello, Kobayashi, Nagao, Kimura, Mutsumi
- Authors: Ikeuchi, Takuro , Mack, John , Nyokong, Tebello , Kobayashi, Nagao , Kimura, Mutsumi
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/239709 , vital:50757 , xlink:href="https://doi.org/10.1021/acs.langmuir.6b03552"
- Description: A water-soluble zinc phthalocyanine (ZnPc) complex with four negatively charged electron-withdrawing sulfonic acid substituents at the nonperipheral positions (α-ZnTSPc) is found to have a high singlet oxygen (1O2) quantum yield and exhibits high photostability. The formation of aggregates is hindered and the highest occupied molecular orbital is significantly stabilized, making α-ZnTSPc potentially suitable for its use as a photosensitizer for photodynamic therapy and photoimmunotherapy. Atomic force microscopy (AFM) reveals that mixtures of the negatively charged α-ZnTSPc complex with a similar positively charged ZnPc were found to result in the self-assembly of one-dimensional accordion-like fibers. Supramolecular fibers can be formed in aqueous solutions through intermolecular electrostatic and donor–acceptor interactions between the two water-soluble ZnPcs.
- Full Text:
- Authors: Ikeuchi, Takuro , Mack, John , Nyokong, Tebello , Kobayashi, Nagao , Kimura, Mutsumi
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/239709 , vital:50757 , xlink:href="https://doi.org/10.1021/acs.langmuir.6b03552"
- Description: A water-soluble zinc phthalocyanine (ZnPc) complex with four negatively charged electron-withdrawing sulfonic acid substituents at the nonperipheral positions (α-ZnTSPc) is found to have a high singlet oxygen (1O2) quantum yield and exhibits high photostability. The formation of aggregates is hindered and the highest occupied molecular orbital is significantly stabilized, making α-ZnTSPc potentially suitable for its use as a photosensitizer for photodynamic therapy and photoimmunotherapy. Atomic force microscopy (AFM) reveals that mixtures of the negatively charged α-ZnTSPc complex with a similar positively charged ZnPc were found to result in the self-assembly of one-dimensional accordion-like fibers. Supramolecular fibers can be formed in aqueous solutions through intermolecular electrostatic and donor–acceptor interactions between the two water-soluble ZnPcs.
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Allelopathic effects of Lantana camara on indigenous forest species in South Africa
- Ruwanza, Sheunesu, Shackleton, Charlie M
- Authors: Ruwanza, Sheunesu , Shackleton, Charlie M
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182296 , vital:43818 , xlink:href="http://www.allelopathyjournal.org/?"
- Description: Lantana camara, is an invasive plant in South Africa and greatly influences the forest spp. In greenhouse, we evaluated the allelopathic effects of aqueous extracts of L. camara leaf, stem and root on 5-test species, (3-forest species viz., Acacia natalitia, Kiggalaria africana and Searsia crenata and 2-crops: Solanum lycopersicum and Lactuca sativa). Potential allelopathic compounds present in L. camara leaf, stem and root aqueous extracts were identified using gas chromatography mass spectrometry (GC-MS). The leaf, stem and root aqueous extracts of L. camara reduced the seed germination and seedling growth of all test species showing that L. camara aqueous extracts were deleterious to all test species. We identified 92 major volatile organic components in L. camara aqueous extracts. These compounds had the potential to inhibit the germination and seedling growth of test crops. The leaf, stem and root aqueous extracts of L. camara contained the allelopathic compounds that inhibited the germination and seedling growth of indigenous forest species and crop species.
- Full Text:
- Authors: Ruwanza, Sheunesu , Shackleton, Charlie M
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182296 , vital:43818 , xlink:href="http://www.allelopathyjournal.org/?"
- Description: Lantana camara, is an invasive plant in South Africa and greatly influences the forest spp. In greenhouse, we evaluated the allelopathic effects of aqueous extracts of L. camara leaf, stem and root on 5-test species, (3-forest species viz., Acacia natalitia, Kiggalaria africana and Searsia crenata and 2-crops: Solanum lycopersicum and Lactuca sativa). Potential allelopathic compounds present in L. camara leaf, stem and root aqueous extracts were identified using gas chromatography mass spectrometry (GC-MS). The leaf, stem and root aqueous extracts of L. camara reduced the seed germination and seedling growth of all test species showing that L. camara aqueous extracts were deleterious to all test species. We identified 92 major volatile organic components in L. camara aqueous extracts. These compounds had the potential to inhibit the germination and seedling growth of test crops. The leaf, stem and root aqueous extracts of L. camara contained the allelopathic compounds that inhibited the germination and seedling growth of indigenous forest species and crop species.
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Allopatric speciation in the flightless Phoberus capensis (Coleoptera: Trogidae) group, with description of two new species
- Strümpher, Werner P, Sole, Catherine L, Villet, Martin H, Scholtz, Clarke H
- Authors: Strümpher, Werner P , Sole, Catherine L , Villet, Martin H , Scholtz, Clarke H
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/442730 , vital:74028 , ISBN , https://brill.com/view/journals/ise/47/2/article-p149_4.xml
- Description: The name Phoberus capensis (Scholtz) is applied to a small flightless, keratinophagous beetle endemic to the Cape Floristic Region of South Africa. Its gross distribution stretches from roughly 1000 km from the Cederberg (32°24’22” S, 19°04’50” E) to Grahamstown (33°20’07” S, 26°32’50” E). The populations are spatially discrete, restricted to relict forests of the southern Cape and disjunct high montane refugia of the Cape Fold Mountains. We test the hypothesis that there is more than one distinct species nested within the name P . capensis . Phylogenetic relationships among populations were inferred using molecular sequence data. The results support three distinct evolutionary lineages, which were also supported by morphological characters. Divergence time estimates suggest Pliocene-Pleistocene diversification. Based on these results, it is suggested that the P. capensis lineage experienced climatically-driven allopatric speciation with sheltered Afrotemperate forests and high mountain peaks serving as important refugia in response to climatic ameliorations. The P. capensis complex thus represents a speciation process in which flight-restricted populations evolved in close allopatry, possibly as recently as the Pleistocene. Two divergent and geographically distinct lineages are described as novel species: The new species, P . disjunctus sp. n. and P . herminae sp. n., are illustrated by photographs of habitus and male aedeagi.
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- Authors: Strümpher, Werner P , Sole, Catherine L , Villet, Martin H , Scholtz, Clarke H
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/442730 , vital:74028 , ISBN , https://brill.com/view/journals/ise/47/2/article-p149_4.xml
- Description: The name Phoberus capensis (Scholtz) is applied to a small flightless, keratinophagous beetle endemic to the Cape Floristic Region of South Africa. Its gross distribution stretches from roughly 1000 km from the Cederberg (32°24’22” S, 19°04’50” E) to Grahamstown (33°20’07” S, 26°32’50” E). The populations are spatially discrete, restricted to relict forests of the southern Cape and disjunct high montane refugia of the Cape Fold Mountains. We test the hypothesis that there is more than one distinct species nested within the name P . capensis . Phylogenetic relationships among populations were inferred using molecular sequence data. The results support three distinct evolutionary lineages, which were also supported by morphological characters. Divergence time estimates suggest Pliocene-Pleistocene diversification. Based on these results, it is suggested that the P. capensis lineage experienced climatically-driven allopatric speciation with sheltered Afrotemperate forests and high mountain peaks serving as important refugia in response to climatic ameliorations. The P. capensis complex thus represents a speciation process in which flight-restricted populations evolved in close allopatry, possibly as recently as the Pleistocene. Two divergent and geographically distinct lineages are described as novel species: The new species, P . disjunctus sp. n. and P . herminae sp. n., are illustrated by photographs of habitus and male aedeagi.
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An overview of linux container based network emulation
- Peach, Schalk, Irwin, Barry V W, van Heerden, Renier
- Authors: Peach, Schalk , Irwin, Barry V W , van Heerden, Renier
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430095 , vital:72665 , https://www.proceedings.com/30838.html
- Description: The objective of this paper is to assess the current state of Container-Based Emulator implementations on the Linux platform. Through a nar-rative overview, a selection of open source Container-Based emulators are analysed to collect information regarding the technologies used to construct them to assess the current state of this emerging technology. Container-Based Emulators allows the creation of small emulated net-works on commodity hardware through the use of kernel level virtualiza-tion techniques, also referred to as containerisation. Container-Based Emulators act as a management tool to control containers and the ap-plications that execute within them. The ability of Container Based Emu-lators to create repeatable and controllable test networks makes it ideal for use as training and experimentation tools in the information security and network management fields. Due to the ease of use and low hard-ware requirements, the tools present a low cost alternative to other forms of network experimentation platforms. Through a review of cur-rent literature and source code, the current state of Container-Based Emulators is assessed.
- Full Text:
- Authors: Peach, Schalk , Irwin, Barry V W , van Heerden, Renier
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430095 , vital:72665 , https://www.proceedings.com/30838.html
- Description: The objective of this paper is to assess the current state of Container-Based Emulator implementations on the Linux platform. Through a nar-rative overview, a selection of open source Container-Based emulators are analysed to collect information regarding the technologies used to construct them to assess the current state of this emerging technology. Container-Based Emulators allows the creation of small emulated net-works on commodity hardware through the use of kernel level virtualiza-tion techniques, also referred to as containerisation. Container-Based Emulators act as a management tool to control containers and the ap-plications that execute within them. The ability of Container Based Emu-lators to create repeatable and controllable test networks makes it ideal for use as training and experimentation tools in the information security and network management fields. Due to the ease of use and low hard-ware requirements, the tools present a low cost alternative to other forms of network experimentation platforms. Through a review of cur-rent literature and source code, the current state of Container-Based Emulators is assessed.
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Antibacterial effects of Alchornea cordifolia (Schumach. and Thonn.) Müll. Arg extracts and compounds on gastrointestinal, skin, respiratory and urinary tract pathogens
- Siwe-Noundou, Xavier, Krause, Rui W M, van Vuuren, Sandy, Tantoh Ndinteh, Derek, Olivier, D K
- Authors: Siwe-Noundou, Xavier , Krause, Rui W M , van Vuuren, Sandy , Tantoh Ndinteh, Derek , Olivier, D K
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/195418 , vital:45563 , xlink:href="https://doi.org/10.1016/j.jep.2015.12.043"
- Description: Ethnopharmacological relevance:The leaves, stems and roots ofAlchornea cordifolia(Schumach. andThonn.) Müll. Arg. are used as traditional medicine in many African countries for the management ofgastrointestinal, respiratory and urinary tract infections as well as for the treatment of wounds.Aim of the study:To determine the in vitro antibacterial activity of the crude extracts of leaves and stemsofA. cordifoliaon gastrointestinal, skin, respiratory and urinary tract pathogens and to identify thecompounds in the extracts that may be responsible for this activity.Materials and methods:The antibacterial activities of crude extracts [hexane, chloroform (CHCl3), ethylacetate (EtOAc), ethanol (EtOH), methanol (MeOH) and water (H2O)] as well as pure compounds isolatedfrom these extracts were evaluated by means of the micro-dilution assay against four Gram-positivebacteria, i.e.Bacillus cereusATCC 11778,Enterococcus faecalisATCC 29212, Staphylococcus aureusATCC25923 andS. saprophyticusATCC 15305,as well as four Gram-negative bacterial strains, i.e.EscherichiacoliATCC 25922, Klebsiella pneumoniaeATCC 13883, Moraxella catarrhalisATCC 23246 andProteus mir-abilisATCC 43071. The isolation of the active constituents was undertaken by bio-autographic assays inconjunction with chromatographic techniques. The identification and characterisation of the isolatedcompounds were done using mass spectrometry (MS) and Fourier transformed infrared spectrometry(FTIR) as well as 1D- and 2D- nuclear magnetic resonance (NMR) analyses.Results:The leaves and stems ofA. cordifoliaexhibited varied antibacterial activity against all eight pa-thogens. Most of the MIC values ranged between 63 and 2000mg/ml. The highest activities for the crudeextracts (63mg/ml) were observed againstS. saprophyticus[stem (EtOAc, CHCl3and hexane), leaves(MeOH, EtOH, EtOAc and CHCl3)],E. coli[stem (MeOH and EtOH), leaves (MeOH, EtOH, EtOAc andCHCl3)],M. catarrhalis[leaves (EtOAc and CHCl3)],K. pneumoniae[stem (CHCl3), leaves (CHCl3)] andS.aureus[leaves (CHCl3)]. Seven constituents [stigmasterol (1), stigmasta-4,22-dien-3-one (2), friedelin (3),friedelane-3-one-28-al (4), 3-O-acetyl-aleuritolic acid (5), 3-O-acetyl-erythrodiol (6) and methyl-3,4,5-trihydroxybenzoate (methyl gallate) (7)] were isolated from the stem MeOH extract. All these com-pounds displayed some antibacterial activity against the eight pathogens with highest activity againstS.saprophyticus(2mg/ml). Furthermore, this is thefirst report of compounds1,2,3,4,6and7isolated fromA. cordifoliaand where a complete set of 2D-NMR data for fridelane-3-one-28-al (4) is presented.Conclusion:The study demonstrated that the antibacterial activities ofA. cordifoliaextracts may be dueto the presence of the seven isolated compounds, where compounds3–6showed the best activity. Theobserved activity against gastrointestinal, skin, respiratory and urinary tract pathogens supports thetraditional use for the treatment of such ailments.
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- Authors: Siwe-Noundou, Xavier , Krause, Rui W M , van Vuuren, Sandy , Tantoh Ndinteh, Derek , Olivier, D K
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/195418 , vital:45563 , xlink:href="https://doi.org/10.1016/j.jep.2015.12.043"
- Description: Ethnopharmacological relevance:The leaves, stems and roots ofAlchornea cordifolia(Schumach. andThonn.) Müll. Arg. are used as traditional medicine in many African countries for the management ofgastrointestinal, respiratory and urinary tract infections as well as for the treatment of wounds.Aim of the study:To determine the in vitro antibacterial activity of the crude extracts of leaves and stemsofA. cordifoliaon gastrointestinal, skin, respiratory and urinary tract pathogens and to identify thecompounds in the extracts that may be responsible for this activity.Materials and methods:The antibacterial activities of crude extracts [hexane, chloroform (CHCl3), ethylacetate (EtOAc), ethanol (EtOH), methanol (MeOH) and water (H2O)] as well as pure compounds isolatedfrom these extracts were evaluated by means of the micro-dilution assay against four Gram-positivebacteria, i.e.Bacillus cereusATCC 11778,Enterococcus faecalisATCC 29212, Staphylococcus aureusATCC25923 andS. saprophyticusATCC 15305,as well as four Gram-negative bacterial strains, i.e.EscherichiacoliATCC 25922, Klebsiella pneumoniaeATCC 13883, Moraxella catarrhalisATCC 23246 andProteus mir-abilisATCC 43071. The isolation of the active constituents was undertaken by bio-autographic assays inconjunction with chromatographic techniques. The identification and characterisation of the isolatedcompounds were done using mass spectrometry (MS) and Fourier transformed infrared spectrometry(FTIR) as well as 1D- and 2D- nuclear magnetic resonance (NMR) analyses.Results:The leaves and stems ofA. cordifoliaexhibited varied antibacterial activity against all eight pa-thogens. Most of the MIC values ranged between 63 and 2000mg/ml. The highest activities for the crudeextracts (63mg/ml) were observed againstS. saprophyticus[stem (EtOAc, CHCl3and hexane), leaves(MeOH, EtOH, EtOAc and CHCl3)],E. coli[stem (MeOH and EtOH), leaves (MeOH, EtOH, EtOAc andCHCl3)],M. catarrhalis[leaves (EtOAc and CHCl3)],K. pneumoniae[stem (CHCl3), leaves (CHCl3)] andS.aureus[leaves (CHCl3)]. Seven constituents [stigmasterol (1), stigmasta-4,22-dien-3-one (2), friedelin (3),friedelane-3-one-28-al (4), 3-O-acetyl-aleuritolic acid (5), 3-O-acetyl-erythrodiol (6) and methyl-3,4,5-trihydroxybenzoate (methyl gallate) (7)] were isolated from the stem MeOH extract. All these com-pounds displayed some antibacterial activity against the eight pathogens with highest activity againstS.saprophyticus(2mg/ml). Furthermore, this is thefirst report of compounds1,2,3,4,6and7isolated fromA. cordifoliaand where a complete set of 2D-NMR data for fridelane-3-one-28-al (4) is presented.Conclusion:The study demonstrated that the antibacterial activities ofA. cordifoliaextracts may be dueto the presence of the seven isolated compounds, where compounds3–6showed the best activity. Theobserved activity against gastrointestinal, skin, respiratory and urinary tract pathogens supports thetraditional use for the treatment of such ailments.
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Application of Baylis-Hillman methodology in the direct construction of chromone derivatives
- Faridoon, H, Olomola, Temitope O, Klein, Rosalyn, Kaye, Perry T
- Authors: Faridoon, H , Olomola, Temitope O , Klein, Rosalyn , Kaye, Perry T
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/442488 , vital:73992 , https://doi.org/10.1016/j.tet.2015.11.039
- Description: Pyridinium chlorochromate oxidation of Baylis-Hillman-derived tert-butyl 2H-chromene-3-carboxylates affords chromone-3-carboxylate esters, providing the first application of Baylis-Hillman methodology in a direct and convenient three-step synthesis of chromone derivatives.
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- Authors: Faridoon, H , Olomola, Temitope O , Klein, Rosalyn , Kaye, Perry T
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/442488 , vital:73992 , https://doi.org/10.1016/j.tet.2015.11.039
- Description: Pyridinium chlorochromate oxidation of Baylis-Hillman-derived tert-butyl 2H-chromene-3-carboxylates affords chromone-3-carboxylate esters, providing the first application of Baylis-Hillman methodology in a direct and convenient three-step synthesis of chromone derivatives.
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Assimilation of organic and inorganic nutrients by Erica root fungi from the fynbos ecosystem
- Bizabani, Christine, Dames, Joanna F
- Authors: Bizabani, Christine , Dames, Joanna F
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/444079 , vital:74183 , https://doi.org/10.1016/j.funbio.2015.11.006
- Description: Erica dominate the fynbos ecosystem, which is characterized by acidic soils that are rich in organic matter. The ericaceae associate with ericoid mycorrhizal (ERM) fungi for survival. In this study fungal biomass accumulation in vitro was used to determine nutrient utilisation of various inorganic and organic substrates. This is an initial step towards establishment of the ecological roles of typical ERM fungi and other root fungi associated with Erica plants, with regard to host nutrition. Meliniomyces sp., Acremonium implicatum, Leohumicola sp., Cryptosporiopsis erica, Oidiodendron maius and an unidentified Helotiales fungus were selected from fungi previously isolated and identified from Erica roots. Sole nitrogen sources ammonium, nitrate, arginine and Bovine Serum Albumin (BSA) were tested. Meliniomyces and Leohumicola species were able to utilise BSA effectively. Phosphorus nutrition was tested using orthophosphate, sodium inositol hexaphosphate and DNA. Most isolates preferred orthophosphate. Meliniomyces sp. and A. implicatum were able to accumulate significant biomass using DNA. Carbon utilisation was tested using glucose, cellobiose, carboxymethylcellulose, pectin and tannic acid substrates. All fungal isolates produced high biomass on glucose and cellobiose. The ability to utilize organic nutrient sources in culture, illustrates their potential role of these fungi in host nutrition in the fynbos ecosystem.
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- Authors: Bizabani, Christine , Dames, Joanna F
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/444079 , vital:74183 , https://doi.org/10.1016/j.funbio.2015.11.006
- Description: Erica dominate the fynbos ecosystem, which is characterized by acidic soils that are rich in organic matter. The ericaceae associate with ericoid mycorrhizal (ERM) fungi for survival. In this study fungal biomass accumulation in vitro was used to determine nutrient utilisation of various inorganic and organic substrates. This is an initial step towards establishment of the ecological roles of typical ERM fungi and other root fungi associated with Erica plants, with regard to host nutrition. Meliniomyces sp., Acremonium implicatum, Leohumicola sp., Cryptosporiopsis erica, Oidiodendron maius and an unidentified Helotiales fungus were selected from fungi previously isolated and identified from Erica roots. Sole nitrogen sources ammonium, nitrate, arginine and Bovine Serum Albumin (BSA) were tested. Meliniomyces and Leohumicola species were able to utilise BSA effectively. Phosphorus nutrition was tested using orthophosphate, sodium inositol hexaphosphate and DNA. Most isolates preferred orthophosphate. Meliniomyces sp. and A. implicatum were able to accumulate significant biomass using DNA. Carbon utilisation was tested using glucose, cellobiose, carboxymethylcellulose, pectin and tannic acid substrates. All fungal isolates produced high biomass on glucose and cellobiose. The ability to utilize organic nutrient sources in culture, illustrates their potential role of these fungi in host nutrition in the fynbos ecosystem.
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Can local use assist in controlling invasive alien species in tropical forests?: The case of Lantana camara in southern India
- Kannan, Ramesh, Shackleton, Charlie M, Krishnan, Smitha, Shaanker, Ramanan U
- Authors: Kannan, Ramesh , Shackleton, Charlie M , Krishnan, Smitha , Shaanker, Ramanan U
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/180423 , vital:43387 , xlink:href="https://doi.org/10.1016/j.foreco.2016.06.016"
- Description: Many invasive alien species (IAS) are used by local communities for a variety of subsistence and income generating purposes. This frequently poses a conflict of interest for their removal due to forest conservation and biodiversity concerns. However, if local use can simultaneously check or control specific IAS, the conflict can be avoided and both development and forest conservation perspectives accommodated in the short to medium term. We examine this for Lantana camara invasion in southern India through assessment of the demand for and impacts of harvesting on this globally problematic IAS. We interviewed local artisans regarding their knowledge and quantities of Lantana used, along with forest surveys to estimate Lantana densities and size classes in harvested and unharvested sites, and lastly we undertook controlled cutting in moist and dry deciduous forests in both the wet and dry seasons to examine rate of regrowth and mortality. Over the entire study area the abundance of Lantana far outweighed local demand, but at small scales around villages, density and size classes were significantly reduced through harvesting. The controlled cutting experiment showed marked seasonal differences, with the most severe cutting intensity resulting in significant mortality when Lantana plants were cut in the wet season, but with limited effect when cut in the dry season. We conclude that promoting local use of IAS may be a feasible approach in controlling them and thereby limiting their impacts in forests.
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- Authors: Kannan, Ramesh , Shackleton, Charlie M , Krishnan, Smitha , Shaanker, Ramanan U
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/180423 , vital:43387 , xlink:href="https://doi.org/10.1016/j.foreco.2016.06.016"
- Description: Many invasive alien species (IAS) are used by local communities for a variety of subsistence and income generating purposes. This frequently poses a conflict of interest for their removal due to forest conservation and biodiversity concerns. However, if local use can simultaneously check or control specific IAS, the conflict can be avoided and both development and forest conservation perspectives accommodated in the short to medium term. We examine this for Lantana camara invasion in southern India through assessment of the demand for and impacts of harvesting on this globally problematic IAS. We interviewed local artisans regarding their knowledge and quantities of Lantana used, along with forest surveys to estimate Lantana densities and size classes in harvested and unharvested sites, and lastly we undertook controlled cutting in moist and dry deciduous forests in both the wet and dry seasons to examine rate of regrowth and mortality. Over the entire study area the abundance of Lantana far outweighed local demand, but at small scales around villages, density and size classes were significantly reduced through harvesting. The controlled cutting experiment showed marked seasonal differences, with the most severe cutting intensity resulting in significant mortality when Lantana plants were cut in the wet season, but with limited effect when cut in the dry season. We conclude that promoting local use of IAS may be a feasible approach in controlling them and thereby limiting their impacts in forests.
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Case Studies for UNECCC, UNESCO and CEE The COPART Climate Train
- Authors: McGarry, Dylan K
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/391120 , vital:68622 , xlink:href="https://eeasa.org.za/wp-content/uploads/2017/05/EEASA-Bullitin-2016_18-July-issue-42.pdf"
- Description: To create a listening and educational platform that used various disciplines to understand the impact of Climate Change across South Africa. The objective was to create a multigenre educational space for citizens of South Africa as a means to participate in Climate discussions as an alternative to the COP17 negotiations held in South Africa at the time.
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- Authors: McGarry, Dylan K
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/391120 , vital:68622 , xlink:href="https://eeasa.org.za/wp-content/uploads/2017/05/EEASA-Bullitin-2016_18-July-issue-42.pdf"
- Description: To create a listening and educational platform that used various disciplines to understand the impact of Climate Change across South Africa. The objective was to create a multigenre educational space for citizens of South Africa as a means to participate in Climate discussions as an alternative to the COP17 negotiations held in South Africa at the time.
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Characterization and Electrocatalytic Activity of Nanocomposites Consisting of Nanosized Cobalt Tetraaminophenoxy Phthalocyanine, Multi‐walled Carbon Nanotubes and Gold Nanoparticles
- Shumba, Munyaradzi, Nyokong, Tebello
- Authors: Shumba, Munyaradzi , Nyokong, Tebello
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/188659 , vital:44773 , xlink:href="https://doi.org/10.1002/elan.201501058"
- Description: Glassy carbon electrodes were modified with composites containing cobalt tetraaminophenoxy phthalocyanine nanoparticles (CoTAPhPcNP), multi-walled carbon nanotubes (MWCNT) and gold nanorods (AuNRs). The modified electrodes were studied for their electrocatalytic behavior towards the reduction of hydrogen peroxide. Phthalocyanine nanoparticles significantly improved electron transfer kinetics as compared to phthalocyanines which are not in the nanoparticle form when alone or in the presence of multiwalled carbon nanotubes (MWCNTs). CoTAPhPcNP-MWCNT-GCE proved to be suitable for hydrogen peroxide detection with a catalytic rate constant of 3.45×103 M−1 s−1 and a detection limit of 1.61×10−7 M. Adsorption Gibbs free energy ΔGo was found to be −19.22 kJ mol−1 for CoTAPhPcNP-MWCNT-GCE.
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- Authors: Shumba, Munyaradzi , Nyokong, Tebello
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/188659 , vital:44773 , xlink:href="https://doi.org/10.1002/elan.201501058"
- Description: Glassy carbon electrodes were modified with composites containing cobalt tetraaminophenoxy phthalocyanine nanoparticles (CoTAPhPcNP), multi-walled carbon nanotubes (MWCNT) and gold nanorods (AuNRs). The modified electrodes were studied for their electrocatalytic behavior towards the reduction of hydrogen peroxide. Phthalocyanine nanoparticles significantly improved electron transfer kinetics as compared to phthalocyanines which are not in the nanoparticle form when alone or in the presence of multiwalled carbon nanotubes (MWCNTs). CoTAPhPcNP-MWCNT-GCE proved to be suitable for hydrogen peroxide detection with a catalytic rate constant of 3.45×103 M−1 s−1 and a detection limit of 1.61×10−7 M. Adsorption Gibbs free energy ΔGo was found to be −19.22 kJ mol−1 for CoTAPhPcNP-MWCNT-GCE.
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Citizen Monitoring of The National Water Resource Strategy 2 (NWRS2)
- Wilson, Jessica, Munnik, Victor, Burt, Jane C, Pereira, Taryn, Ngcozela, Thabang, Mokoena, Samson, Lusithi, Thabo, Lotz-Sisitka, Heila, Ndhlovu, December, Ngcanga, Thandiwe, Tshabalala, Mduduzi, James, Manelisi, Mashile, Alexander, Mdululi, Patricia
- Authors: Wilson, Jessica , Munnik, Victor , Burt, Jane C , Pereira, Taryn , Ngcozela, Thabang , Mokoena, Samson , Lusithi, Thabo , Lotz-Sisitka, Heila , Ndhlovu, December , Ngcanga, Thandiwe , Tshabalala, Mduduzi , James, Manelisi , Mashile, Alexander , Mdululi, Patricia
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/436812 , vital:73307 , ISBN 978-1-4312-0922-4 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/2313%20_final.pdf
- Description: In 2014, the South African Water Caucus (SAWC), a network of non-governmental organisations (NGOs) and community-based organisations (CBOs) who are active in the water sec-tor, embarked on a social learning and action research journey supported by the South African Water Research Commission (WRC) to deepen its monitoring of South Africa’s Second Na-tional Water Resources Strategy (NWRS2). They focused on three issues in three cases study areas.
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- Authors: Wilson, Jessica , Munnik, Victor , Burt, Jane C , Pereira, Taryn , Ngcozela, Thabang , Mokoena, Samson , Lusithi, Thabo , Lotz-Sisitka, Heila , Ndhlovu, December , Ngcanga, Thandiwe , Tshabalala, Mduduzi , James, Manelisi , Mashile, Alexander , Mdululi, Patricia
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/436812 , vital:73307 , ISBN 978-1-4312-0922-4 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/2313%20_final.pdf
- Description: In 2014, the South African Water Caucus (SAWC), a network of non-governmental organisations (NGOs) and community-based organisations (CBOs) who are active in the water sec-tor, embarked on a social learning and action research journey supported by the South African Water Research Commission (WRC) to deepen its monitoring of South Africa’s Second Na-tional Water Resources Strategy (NWRS2). They focused on three issues in three cases study areas.
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Citizen Monitoring of the NWRS2. WRC report 2313
- Wilson, Jessica, Munnik, Victor, Burt, Jane C, Pereira, Taryn, Ngcozela, Thabang, Lusithi, Thabo, Lotz-Sisitka, Heila
- Authors: Wilson, Jessica , Munnik, Victor , Burt, Jane C , Pereira, Taryn , Ngcozela, Thabang , Lusithi, Thabo , Lotz-Sisitka, Heila
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/432979 , vital:72920 , xlink:href="https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/2313%20_final.pdf"
- Description: In 2014, the South African Water Caucus (SAWC), a network of non-governmental organisations (NGOs) and community-based organisations (CBOs) who are active in the water sector, embarked on a social learning and action research journey supported by the South African Water Research Commission (WRC) to deepen its monitoring of South Africa’s Second National Water Resources Strategy (NWRS2). They focused on three issues in three cases study areas.
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- Authors: Wilson, Jessica , Munnik, Victor , Burt, Jane C , Pereira, Taryn , Ngcozela, Thabang , Lusithi, Thabo , Lotz-Sisitka, Heila
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/432979 , vital:72920 , xlink:href="https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/2313%20_final.pdf"
- Description: In 2014, the South African Water Caucus (SAWC), a network of non-governmental organisations (NGOs) and community-based organisations (CBOs) who are active in the water sector, embarked on a social learning and action research journey supported by the South African Water Research Commission (WRC) to deepen its monitoring of South Africa’s Second National Water Resources Strategy (NWRS2). They focused on three issues in three cases study areas.
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Co-designing research on transgressive learning in times of climate change
- Lotz-Sisitka, Heila, Ali, Million B, Mphepho, Gibson, Chaves, Martha, Macintyre, Thomas, Pesanayi, Tichaona V, Wals, Arjen E, Mukute, Mutizwa, Kronlid, David O, Tran, Duc, Joon, Deepika, McGarry, Dylan K
- Authors: Lotz-Sisitka, Heila , Ali, Million B , Mphepho, Gibson , Chaves, Martha , Macintyre, Thomas , Pesanayi, Tichaona V , Wals, Arjen E , Mukute, Mutizwa , Kronlid, David O , Tran, Duc , Joon, Deepika , McGarry, Dylan K
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182472 , vital:43833 , xlink:href="https://doi.org/10.1016/j.cosust.2016.04.004"
- Description: This paper reflects on the epistemological context for the co-design of a research programme on transformative, transgressive learning emerging at the nexus of climate change, water and food security, energy and social justice. It outlines a sequence of learning actions that we, as a group of collaborating partners in a Transformative Knowledge Network (TKN) undertook to co-design a research programme, firstly in situ in various case study contexts, and secondly together across case study contexts. Finally, it provides some reflections and learning points.
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- Authors: Lotz-Sisitka, Heila , Ali, Million B , Mphepho, Gibson , Chaves, Martha , Macintyre, Thomas , Pesanayi, Tichaona V , Wals, Arjen E , Mukute, Mutizwa , Kronlid, David O , Tran, Duc , Joon, Deepika , McGarry, Dylan K
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182472 , vital:43833 , xlink:href="https://doi.org/10.1016/j.cosust.2016.04.004"
- Description: This paper reflects on the epistemological context for the co-design of a research programme on transformative, transgressive learning emerging at the nexus of climate change, water and food security, energy and social justice. It outlines a sequence of learning actions that we, as a group of collaborating partners in a Transformative Knowledge Network (TKN) undertook to co-design a research programme, firstly in situ in various case study contexts, and secondly together across case study contexts. Finally, it provides some reflections and learning points.
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Collaborative learning of water conservation practices: cultivation and expansion of a learning network around rainwater harvesting demonstration sites in the Eastern Cape, South Africa
- Pesanayi, Tichaona V, Weaver, Kim N
- Authors: Pesanayi, Tichaona V , Weaver, Kim N
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/392086 , vital:68720 , xlink:href="https://www.ajol.info/index.php/sajae/article/view/138570"
- Description: Learning together in mediated voluntary networks can mobilise skills and innovations that help to facilitate learning and uptake of rainwater harvesting and conservation practices. It boosts extension capacity while at the same time growing farmer capabilities, tapping on the distributed cognition. These practices help to heal wicked problems of drought and global change challenges affecting marginalised farmers in South Africa. South Africa has water, nutrition and food security challenges, especially the Eastern Cape Province where there is a relatively high level of poverty. These challenges place heavy pressure on the agricultural sector as it is the main user of the allocated water in the country. In this paper, the learning of and agency for rainwater harvesting and conservation practices are explored as responses to these challenges. Despite existing cultural histories of such practices among the amaXhosa people, information on these practices is not readily available to small-scale rural farmers who thus struggle for the want of knowing. This research forms part of a Water Research Commission project, Amanzi for Food, whose intention is to mediate collaborative and co-engaged learning among networked farmers, extension workers, researchers and agricultural educators through course-mediated use of Water Research Commission rainwater harvesting and conservation materials.
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- Authors: Pesanayi, Tichaona V , Weaver, Kim N
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/392086 , vital:68720 , xlink:href="https://www.ajol.info/index.php/sajae/article/view/138570"
- Description: Learning together in mediated voluntary networks can mobilise skills and innovations that help to facilitate learning and uptake of rainwater harvesting and conservation practices. It boosts extension capacity while at the same time growing farmer capabilities, tapping on the distributed cognition. These practices help to heal wicked problems of drought and global change challenges affecting marginalised farmers in South Africa. South Africa has water, nutrition and food security challenges, especially the Eastern Cape Province where there is a relatively high level of poverty. These challenges place heavy pressure on the agricultural sector as it is the main user of the allocated water in the country. In this paper, the learning of and agency for rainwater harvesting and conservation practices are explored as responses to these challenges. Despite existing cultural histories of such practices among the amaXhosa people, information on these practices is not readily available to small-scale rural farmers who thus struggle for the want of knowing. This research forms part of a Water Research Commission project, Amanzi for Food, whose intention is to mediate collaborative and co-engaged learning among networked farmers, extension workers, researchers and agricultural educators through course-mediated use of Water Research Commission rainwater harvesting and conservation materials.
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