A ring-closing metathesis approach to eight-membered benzannelated scaffolds and subsequent internal alkene isomerizations
- Taher, Abu, Aderibigbe, Blessing A, Morgans, Garreth L, Madeley, Lee G, Khanye, Setshaba D, Van der Westhuizen, Leandi, Fernandes, Manuel A, Smith, Vincent J, Michael, Joseph P, Green, Ivan R, Van Otterlo, Willem A L
- Authors: Taher, Abu , Aderibigbe, Blessing A , Morgans, Garreth L , Madeley, Lee G , Khanye, Setshaba D , Van der Westhuizen, Leandi , Fernandes, Manuel A , Smith, Vincent J , Michael, Joseph P , Green, Ivan R , Van Otterlo, Willem A L
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/66252 , vital:28925 , https://doi.org/10.1016/j.tet.2012.12.043
- Description: publisher version , A set of eight-membered benzannelated heterocycles containing two heteroatoms (O,O, NR,NR and O,NR where R=protecting group) was synthesized by ring-closing metathesis from the corresponding ortho-bis-allyl precursors. In this manner, 7-methoxy-2,5-dihydro-1,6-benzodioxocine, 1,2,5,6-tetrahydro-1,6-benzodiazocines, 5,6-dihydro-2H-1,6-benzoxazocines and 5,6,9,10-tetrahydropyrido[2,3-b][1,4]diazocine were synthesized. A number of these compounds were then treated with the catalyst [RuClH(CO)(PPh3)3] to facilitate isomerization of the alkene into conjugation with the heteroatoms in the eight-membered ring. Quite surprisingly, an equal ratio of regioisomers was obtained, even if the heteroatoms were different.
- Full Text: false
- Authors: Taher, Abu , Aderibigbe, Blessing A , Morgans, Garreth L , Madeley, Lee G , Khanye, Setshaba D , Van der Westhuizen, Leandi , Fernandes, Manuel A , Smith, Vincent J , Michael, Joseph P , Green, Ivan R , Van Otterlo, Willem A L
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/66252 , vital:28925 , https://doi.org/10.1016/j.tet.2012.12.043
- Description: publisher version , A set of eight-membered benzannelated heterocycles containing two heteroatoms (O,O, NR,NR and O,NR where R=protecting group) was synthesized by ring-closing metathesis from the corresponding ortho-bis-allyl precursors. In this manner, 7-methoxy-2,5-dihydro-1,6-benzodioxocine, 1,2,5,6-tetrahydro-1,6-benzodiazocines, 5,6-dihydro-2H-1,6-benzoxazocines and 5,6,9,10-tetrahydropyrido[2,3-b][1,4]diazocine were synthesized. A number of these compounds were then treated with the catalyst [RuClH(CO)(PPh3)3] to facilitate isomerization of the alkene into conjugation with the heteroatoms in the eight-membered ring. Quite surprisingly, an equal ratio of regioisomers was obtained, even if the heteroatoms were different.
- Full Text: false
Ancient and modern hybridization between Lucilia sericata and L. cuprina (Diptera: Calliphoridae)
- Williams, Kirstin A, Villet, Martin H
- Authors: Williams, Kirstin A , Villet, Martin H
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/442633 , vital:74017 , 10.14411/eje.2013.029
- Description: There are important but inconsistent differences in breeding site preference between the blow flies Lucilia sericata (Meigen, 1826) and L. cuprina (Wiedemann, 1830)(Diptera: Calliphoridae) that have significance for medical and veterinary science. These inconsistencies might arise from hybridisation. The species are difficult to distinguish using external morphology, although the male genitalia are distinctive and there are reliable molecular markers. Molecular evidence of modern hybridisation, derived from a newly developed nuclear marker, the period (per) gene, is presented here. This has implications for identifications of these species based on mtDNA, and may lead to an explanation of the medical and veterinary anomalies noted in these species.
- Full Text:
- Authors: Williams, Kirstin A , Villet, Martin H
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/442633 , vital:74017 , 10.14411/eje.2013.029
- Description: There are important but inconsistent differences in breeding site preference between the blow flies Lucilia sericata (Meigen, 1826) and L. cuprina (Wiedemann, 1830)(Diptera: Calliphoridae) that have significance for medical and veterinary science. These inconsistencies might arise from hybridisation. The species are difficult to distinguish using external morphology, although the male genitalia are distinctive and there are reliable molecular markers. Molecular evidence of modern hybridisation, derived from a newly developed nuclear marker, the period (per) gene, is presented here. This has implications for identifications of these species based on mtDNA, and may lead to an explanation of the medical and veterinary anomalies noted in these species.
- Full Text:
Being South African and belonging: the status and practice of mediated citizenship in a new democracy
- Wasserman, Herman, Garman, Anthea
- Authors: Wasserman, Herman , Garman, Anthea
- Date: 2013
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/159769 , vital:40342 , ISBN 978-1-84888-186-0
- Description: Democratic South Africa, with its highly inclusive constitution and embrace of all races, creeds and colours, could be understood as having an ideal form of citizenship to be emulated by other nations. At the heart of the 1996 constitution is the eradication of apartheid separation and the provision that all South Africans have shared humanity (‘ubuntu’). The Truth and Reconciliation Commission entrenched three founding critical ideas in public life: the right to talk, the recognition of shared humanity and the impulse to speak out about the horrors of the past. As a result the public sphere is filled with a great outpouring of personal stories and experiences in both the mainstream and popular forms of media. But South Africans continue to be preoccupied with the status of their citizenship; who a South African is and who belongs is uppermost in many public conversations.
- Full Text:
- Authors: Wasserman, Herman , Garman, Anthea
- Date: 2013
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/159769 , vital:40342 , ISBN 978-1-84888-186-0
- Description: Democratic South Africa, with its highly inclusive constitution and embrace of all races, creeds and colours, could be understood as having an ideal form of citizenship to be emulated by other nations. At the heart of the 1996 constitution is the eradication of apartheid separation and the provision that all South Africans have shared humanity (‘ubuntu’). The Truth and Reconciliation Commission entrenched three founding critical ideas in public life: the right to talk, the recognition of shared humanity and the impulse to speak out about the horrors of the past. As a result the public sphere is filled with a great outpouring of personal stories and experiences in both the mainstream and popular forms of media. But South Africans continue to be preoccupied with the status of their citizenship; who a South African is and who belongs is uppermost in many public conversations.
- Full Text:
Comparisons of the thermal physiology of water hyacinth biological control agents: predicting establishment and distribution pre-and post-release
- May, Bronwen, Coetzee, Julie A
- Authors: May, Bronwen , Coetzee, Julie A
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/123476 , vital:35446 , https://doi.10.1111/eea.120628
- Description: Investigations into the thermal physiology of weed biological control agents may elucidate reasons for establishment failure following release. Such studies have shown that the success of water hyacinth biological control in South Africa remains variable in the high-lying interior Highveld region, because the control agents are restricted to establishment and development due to extreme winter conditions. To determine the importance of thermal physiology studies, both pre- and post-release, this study compared the known thermal requirements of Eccritotarsus catarinensis (Carvalho) (Hemiptera: Miridae) released in 1996, with those of an agent released in 1990, Niphograpta albiguttalis (Warren) (Lepidoptera: Pyralidae) and a candidate agent, Megamelus scutellaris Berg (Hemiptera: Delphacidae), which is currently under consideration for release. The lower developmental threshold (to) and rate of development (K) were determined for N. albiguttalis and M. scutellaris, using a reduced axis regression, and incorporated into a degree-day model which compared the number of generations that E. catarinensis, N. albiguttalis, and M. scutellaris are capable of producing annually at any given site in South Africa. The degree-day models predicted that N. albiguttalis (K = 439.43, to = 9.866) can complete 4–11 generations per year, whereas M. scutellaris (K = 502.96, to = 11.458) can only complete 0–10 generations per year, compared with E. catarinensis (K = 342, to = 10.3) which is predicted to complete 3–14 generations per year. This suggests that the candidate agent, M. scutellaris, will not fare better in establishment than the other two agents that have been released in the Highveld, and that it may not be worth releasing an agent with higher thermal requirements than the agents that already occur in these high-lying areas. Thermal physiology studies conducted prior to release are important tools in biological control programmes, particularly those in resource-limited countries, to prevent wasting efforts in getting an agent established.
- Full Text:
- Authors: May, Bronwen , Coetzee, Julie A
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/123476 , vital:35446 , https://doi.10.1111/eea.120628
- Description: Investigations into the thermal physiology of weed biological control agents may elucidate reasons for establishment failure following release. Such studies have shown that the success of water hyacinth biological control in South Africa remains variable in the high-lying interior Highveld region, because the control agents are restricted to establishment and development due to extreme winter conditions. To determine the importance of thermal physiology studies, both pre- and post-release, this study compared the known thermal requirements of Eccritotarsus catarinensis (Carvalho) (Hemiptera: Miridae) released in 1996, with those of an agent released in 1990, Niphograpta albiguttalis (Warren) (Lepidoptera: Pyralidae) and a candidate agent, Megamelus scutellaris Berg (Hemiptera: Delphacidae), which is currently under consideration for release. The lower developmental threshold (to) and rate of development (K) were determined for N. albiguttalis and M. scutellaris, using a reduced axis regression, and incorporated into a degree-day model which compared the number of generations that E. catarinensis, N. albiguttalis, and M. scutellaris are capable of producing annually at any given site in South Africa. The degree-day models predicted that N. albiguttalis (K = 439.43, to = 9.866) can complete 4–11 generations per year, whereas M. scutellaris (K = 502.96, to = 11.458) can only complete 0–10 generations per year, compared with E. catarinensis (K = 342, to = 10.3) which is predicted to complete 3–14 generations per year. This suggests that the candidate agent, M. scutellaris, will not fare better in establishment than the other two agents that have been released in the Highveld, and that it may not be worth releasing an agent with higher thermal requirements than the agents that already occur in these high-lying areas. Thermal physiology studies conducted prior to release are important tools in biological control programmes, particularly those in resource-limited countries, to prevent wasting efforts in getting an agent established.
- Full Text:
Control protocol command translation for device interoperability on ethernet AVB networks
- Foss, Richard, Igumbor, Osedum P
- Authors: Foss, Richard , Igumbor, Osedum P
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/426978 , vital:72405 , https://www.aes.org/e-lib/browse.cfm?elib=16707
- Description: Audio/Video Bridging (AVB) on Ethernet refers to a suite of standards that allows for deterministic and guaranteed delivery of audio and video content on Virtual Local Area Networks (VLAN). A requirement for the networking of audio devices is to allow for remote establishment and destruction of audio stream connections. There are a number of sound control protocols that utilize AVB transport, and this paper describes an approach for common control and interoperability among them. To demonstrate this approach, this paper describes the design and implementation of a command translator that enables communication between AES64 and OSC-networked AVB devices. Results from a quantitative analysis reveal that when a proxy is used for connection management, noticeable delays are not added to a user’s visual and auditory perception.
- Full Text:
- Authors: Foss, Richard , Igumbor, Osedum P
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/426978 , vital:72405 , https://www.aes.org/e-lib/browse.cfm?elib=16707
- Description: Audio/Video Bridging (AVB) on Ethernet refers to a suite of standards that allows for deterministic and guaranteed delivery of audio and video content on Virtual Local Area Networks (VLAN). A requirement for the networking of audio devices is to allow for remote establishment and destruction of audio stream connections. There are a number of sound control protocols that utilize AVB transport, and this paper describes an approach for common control and interoperability among them. To demonstrate this approach, this paper describes the design and implementation of a command translator that enables communication between AES64 and OSC-networked AVB devices. Results from a quantitative analysis reveal that when a proxy is used for connection management, noticeable delays are not added to a user’s visual and auditory perception.
- Full Text:
Eudicella trimeni Janson, 1884 (Coleoptera: Scarabaeidae: Cetoniinae: Goliathini): Description of larva with notes on conservation status, biology and taxonomy
- Perissinotto, Renzo, Orozco, Jesús (Entomologist)
- Authors: Perissinotto, Renzo , Orozco, Jesús (Entomologist)
- Date: 2013
- Subjects: Afrotropical , Goliathini , Eudicella trimeni , Scarab beetles , Fruit chafers , Flower chafers , Larva , Grubs , Rosenkäfer
- Language: English
- Type: Article
- Identifier: vital:6559 , http://hdl.handle.net/10962/d1006605 , http://africaninvertebrates.org/ojs/index.php/AI/article/view/307
- Description: Eudicella trimeni is reportedly one of the most endangered species of the genus, having been declared virtually extinct until recently. Present research has shown that the species occurs in an area wider than previously known. However, its habitat is disappearing at a fast rate and the Eastern Cape and KwaZulu-Natal populations appear to be sufficiently different from each other to warrant at least subspecies status and further investigation. Third instar larvae of the northern population were collected recently in the Karkloof Nature Reserve, KwaZulu-Natal. They were reared to adulthood under environmentally controlled conditions and are here described.
- Full Text:
- Authors: Perissinotto, Renzo , Orozco, Jesús (Entomologist)
- Date: 2013
- Subjects: Afrotropical , Goliathini , Eudicella trimeni , Scarab beetles , Fruit chafers , Flower chafers , Larva , Grubs , Rosenkäfer
- Language: English
- Type: Article
- Identifier: vital:6559 , http://hdl.handle.net/10962/d1006605 , http://africaninvertebrates.org/ojs/index.php/AI/article/view/307
- Description: Eudicella trimeni is reportedly one of the most endangered species of the genus, having been declared virtually extinct until recently. Present research has shown that the species occurs in an area wider than previously known. However, its habitat is disappearing at a fast rate and the Eastern Cape and KwaZulu-Natal populations appear to be sufficiently different from each other to warrant at least subspecies status and further investigation. Third instar larvae of the northern population were collected recently in the Karkloof Nature Reserve, KwaZulu-Natal. They were reared to adulthood under environmentally controlled conditions and are here described.
- Full Text:
Evaluating the acceleration of typical scientific problems on the GPU
- Tristram, Dale, Bradshaw, Karen L
- Authors: Tristram, Dale , Bradshaw, Karen L
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/477607 , vital:78103 , ISBN 9781450321129 , https://doi.org/10.1145/2513456.2513473
- Description: General-purpose computation on graphics processing units (GPGPU) has great potential to accelerate many scientific models and algorithms. However, some problems are considerably more difficult to accelerate than others, and it may be difficult for those new to GPGPU to ascertain the difficulty of accelerating a particular problem. Additionally, problems of different levels of difficulty require varying complexities of optimisations to achieve satisfactory results, and currently there is no clear separation between the different levels of known optimisations, which would be helpful to new users of GPGPU. Through what was learned in the acceleration of three problems, problem attributes have been identified to assist in evaluating the difficulty of accelerating a problem on a GPU. We envisage that with further development, these attributes could form the foundation of a difficulty classification system that could be used to determine whether GPU acceleration is practical for a candidate GPU acceleration problem, aid in identifying appropriate techniques and optimisations, and outline the required GPGPU knowledge.
- Full Text:
- Authors: Tristram, Dale , Bradshaw, Karen L
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/477607 , vital:78103 , ISBN 9781450321129 , https://doi.org/10.1145/2513456.2513473
- Description: General-purpose computation on graphics processing units (GPGPU) has great potential to accelerate many scientific models and algorithms. However, some problems are considerably more difficult to accelerate than others, and it may be difficult for those new to GPGPU to ascertain the difficulty of accelerating a particular problem. Additionally, problems of different levels of difficulty require varying complexities of optimisations to achieve satisfactory results, and currently there is no clear separation between the different levels of known optimisations, which would be helpful to new users of GPGPU. Through what was learned in the acceleration of three problems, problem attributes have been identified to assist in evaluating the difficulty of accelerating a problem on a GPU. We envisage that with further development, these attributes could form the foundation of a difficulty classification system that could be used to determine whether GPU acceleration is practical for a candidate GPU acceleration problem, aid in identifying appropriate techniques and optimisations, and outline the required GPGPU knowledge.
- Full Text:
Halogenated oxindole and indoles from the South African marine ascidian Distaplia skoogi:
- Bromley, Candice L, Parker-Nance, Shirley, de la Mare, Jo-Anne, Edkins, Adrienne L, Beukes, Denzil R, Davies-Coleman, Michael T
- Authors: Bromley, Candice L , Parker-Nance, Shirley , de la Mare, Jo-Anne , Edkins, Adrienne L , Beukes, Denzil R , Davies-Coleman, Michael T
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/164918 , vital:41184
- Description: The known 3,6-dibromoindole (1), 6-bromo-3-chloroindole (2) and 6-bromo-2-oxindole (3) were isolated from the marine ascidian (sea squirt) Distapia skoogi collected from Algoa Bay, South Africa. Standard spectroscopic techniques were used to elucidate the structures of 1-3. All three compounds were found to be moderately cytotoxic to metastatic MDA-MB-231 breast cancer cells.
- Full Text:
- Authors: Bromley, Candice L , Parker-Nance, Shirley , de la Mare, Jo-Anne , Edkins, Adrienne L , Beukes, Denzil R , Davies-Coleman, Michael T
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/164918 , vital:41184
- Description: The known 3,6-dibromoindole (1), 6-bromo-3-chloroindole (2) and 6-bromo-2-oxindole (3) were isolated from the marine ascidian (sea squirt) Distapia skoogi collected from Algoa Bay, South Africa. Standard spectroscopic techniques were used to elucidate the structures of 1-3. All three compounds were found to be moderately cytotoxic to metastatic MDA-MB-231 breast cancer cells.
- Full Text:
Hydrellia lagarosiphon Deeming (Diptera: Ephydridae), a potential biological control agent for the submerged aquatic weed, Lagarosiphon major (Ridl.) Moss ex Wager (Hydrocharitaceae)
- Martin, Grant D, Coetzee, Julie A, Baars, Jan-Robert
- Authors: Martin, Grant D , Coetzee, Julie A , Baars, Jan-Robert
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/103912 , vital:32322 , https://doi.org/10.4001/003.021.0118
- Description: The leaf-mining fly, Hydrellia lagarosiphon Deeming (Diptera: Ephydridae), was investigated in its native range in South Africa, to determine its potential as a biological control agent for Lagarosiphon major (Ridl.) Moss ex Wager (Hydrocharitaceae), an invasive submerged macrophyte that is weedy in many parts of the world. The fly was found throughout the indigenous range of the plant in South Africa. High larval abundance was recorded at field sites with nearly all L. major shoots sampled ontaining larvae, with densities of up to 10 larvae per shoot. Adults laid batches of up to 15 eggs, usually on the abaxial sides of L. major leaves. The larvae mined internally, leaving the epidermal tissues of the upper and lower leaves intact. The larvae underwent three instars which took an average of 24 days and pupated within the leaf tissue, from which the adults emerged. Impact studies in the laboratory showed that H. lagarosiphon larval feeding significantly restricted the formation of L. major side branches. Based on its biology and damage caused to the plant, Hydrellia lagarosiphon could be considered as a useful biological control candidate for L. major in countries where the plant is invasive.
- Full Text:
- Authors: Martin, Grant D , Coetzee, Julie A , Baars, Jan-Robert
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/103912 , vital:32322 , https://doi.org/10.4001/003.021.0118
- Description: The leaf-mining fly, Hydrellia lagarosiphon Deeming (Diptera: Ephydridae), was investigated in its native range in South Africa, to determine its potential as a biological control agent for Lagarosiphon major (Ridl.) Moss ex Wager (Hydrocharitaceae), an invasive submerged macrophyte that is weedy in many parts of the world. The fly was found throughout the indigenous range of the plant in South Africa. High larval abundance was recorded at field sites with nearly all L. major shoots sampled ontaining larvae, with densities of up to 10 larvae per shoot. Adults laid batches of up to 15 eggs, usually on the abaxial sides of L. major leaves. The larvae mined internally, leaving the epidermal tissues of the upper and lower leaves intact. The larvae underwent three instars which took an average of 24 days and pupated within the leaf tissue, from which the adults emerged. Impact studies in the laboratory showed that H. lagarosiphon larval feeding significantly restricted the formation of L. major side branches. Based on its biology and damage caused to the plant, Hydrellia lagarosiphon could be considered as a useful biological control candidate for L. major in countries where the plant is invasive.
- Full Text:
Institutions and economic research: a case of location externalities on agricultural resource allocation in the Kat River basin, South Africa. A Rejoinder
- Mbatha, Cyril N, Antrobus, Geoffrey G
- Authors: Mbatha, Cyril N , Antrobus, Geoffrey G
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143002 , vital:38184 , https://0-doi.org.wam.seals.ac.za/10.1080/03031853.2013.798069
- Description: In Mbatha and Antrobus (2008), an argument was put forward against an importation or adoption of universal models or general theorems to explain locally prevailing socio-economic conditions and predict outcomes in varied geographical contexts such as in the Kat River basin. In response to this argument a comment in this edition argues that our “results are caused by, metaphorically speaking, comparing apples and oranges. If, however, all of the relevant information is taken into account, a simple economic model may suffice to depict the situation within the KRV.” Here we illustrate that the comment comes from a misreading of basic details in the original discussion and in its construction and presentation of an alternative model of the KRV conditions the comment reiterates our original argument that general models and theorems are likely to fail to explain local intricacies primarily because they are not founded on local historical institutions.
- Full Text:
- Authors: Mbatha, Cyril N , Antrobus, Geoffrey G
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143002 , vital:38184 , https://0-doi.org.wam.seals.ac.za/10.1080/03031853.2013.798069
- Description: In Mbatha and Antrobus (2008), an argument was put forward against an importation or adoption of universal models or general theorems to explain locally prevailing socio-economic conditions and predict outcomes in varied geographical contexts such as in the Kat River basin. In response to this argument a comment in this edition argues that our “results are caused by, metaphorically speaking, comparing apples and oranges. If, however, all of the relevant information is taken into account, a simple economic model may suffice to depict the situation within the KRV.” Here we illustrate that the comment comes from a misreading of basic details in the original discussion and in its construction and presentation of an alternative model of the KRV conditions the comment reiterates our original argument that general models and theorems are likely to fail to explain local intricacies primarily because they are not founded on local historical institutions.
- Full Text:
Media, citizenship and the politics of belonging in contemporary South Africa:
- Milton, Viola C, Wasserman, Herman, Garman, Anthea
- Authors: Milton, Viola C , Wasserman, Herman , Garman, Anthea
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/159802 , vital:40345 , DOI: 10.1080/02500167.2013.864447
- Description: Drawing on a wide range of theoretical and empirical studies, the articles in this special issue examine issues of citizenship and belonging in South Africa. Questions of belonging and citizenship are neither novel, nor particular to South Africa – they have been high on the intellectual (and popular) agenda internationally since at least the early 1990s. Yet South Africa's history of artificially separating and defining its citizens in the racial regimes of colonialism and apartheid still reverberates today, as is reflected in the continued inequalities marring South African society
- Full Text:
- Authors: Milton, Viola C , Wasserman, Herman , Garman, Anthea
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/159802 , vital:40345 , DOI: 10.1080/02500167.2013.864447
- Description: Drawing on a wide range of theoretical and empirical studies, the articles in this special issue examine issues of citizenship and belonging in South Africa. Questions of belonging and citizenship are neither novel, nor particular to South Africa – they have been high on the intellectual (and popular) agenda internationally since at least the early 1990s. Yet South Africa's history of artificially separating and defining its citizens in the racial regimes of colonialism and apartheid still reverberates today, as is reflected in the continued inequalities marring South African society
- Full Text:
NGOs and rural movements in contemporary South Africa:
- Authors: Helliker, Kirk D
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/144666 , vital:38368 , DOI: 10.1080/02533952.2013.806415
- Description: This article provides a critical examination of relationships between non-governmental organisations (NGOs) and rural movements in post-apartheid South Africa, particularly with regard to the possible subordination of movements to NGOs. In discussing NGOs as a particular organisational form, and in reviewing some arguments pertaining to NGOs and rural movements globally, I explore whether NGOs in South Africa have a progressive role to play in agrarian transformation.
- Full Text:
- Authors: Helliker, Kirk D
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/144666 , vital:38368 , DOI: 10.1080/02533952.2013.806415
- Description: This article provides a critical examination of relationships between non-governmental organisations (NGOs) and rural movements in post-apartheid South Africa, particularly with regard to the possible subordination of movements to NGOs. In discussing NGOs as a particular organisational form, and in reviewing some arguments pertaining to NGOs and rural movements globally, I explore whether NGOs in South Africa have a progressive role to play in agrarian transformation.
- Full Text:
Rehearsing or reversing harmful masculine scripts?: South African men's romance narratives
- Vincent, Louise, Chiwandire, Desire
- Authors: Vincent, Louise , Chiwandire, Desire
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141844 , vital:38009 , DOI: 10.1080/10130950.2013.807081
- Description: In this Article we discuss the results of 42 in-depth qualitative interviews with young black South African men who self-identified as heterosexual and who reported that they were at the time of the interview or had at some time in their lives, experienced being ‘in love’ with a woman. South Africa, as is commonly pointed out, is in the throes of an epidemic of gender based violence. To declare oneself ‘in love’ potentially contradicts some of the core features of what Mogomotsi Mfalapitsa (IRIN, 2009) has referred to as ‘harmful masculinity’ and which he has argued is causally related to male violence against women. These features include emotional detachment, promiscuity, interest in casual sex rather than long-term engagement with a single partner, unwillingness to be ‘tied down’, the hierarchical ordering of gendered relations constructed as men's entitlement to women's ‘respect’ and the need to publically enact masculine heterosexuality. We are interested in whether, in these narratives, the research participants position themselves in opposition to these harmful precepts or, whether they confirm and reiteratively perform assumptions that can be construed as damaging to the prospects of generating more equitable, fair and loving relations between men and women.
- Full Text:
- Authors: Vincent, Louise , Chiwandire, Desire
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141844 , vital:38009 , DOI: 10.1080/10130950.2013.807081
- Description: In this Article we discuss the results of 42 in-depth qualitative interviews with young black South African men who self-identified as heterosexual and who reported that they were at the time of the interview or had at some time in their lives, experienced being ‘in love’ with a woman. South Africa, as is commonly pointed out, is in the throes of an epidemic of gender based violence. To declare oneself ‘in love’ potentially contradicts some of the core features of what Mogomotsi Mfalapitsa (IRIN, 2009) has referred to as ‘harmful masculinity’ and which he has argued is causally related to male violence against women. These features include emotional detachment, promiscuity, interest in casual sex rather than long-term engagement with a single partner, unwillingness to be ‘tied down’, the hierarchical ordering of gendered relations constructed as men's entitlement to women's ‘respect’ and the need to publically enact masculine heterosexuality. We are interested in whether, in these narratives, the research participants position themselves in opposition to these harmful precepts or, whether they confirm and reiteratively perform assumptions that can be construed as damaging to the prospects of generating more equitable, fair and loving relations between men and women.
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The AES64 Connection Management and Control Protocol
- Foss, Richard, Gurdan, Robby, Klinkradt, Bradley, Chigwamba, Nyasha
- Authors: Foss, Richard , Gurdan, Robby , Klinkradt, Bradley , Chigwamba, Nyasha
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/426933 , vital:72402 , https://www.aes.org/e-lib/browse.cfm?elib=16705
- Description: AES64, which is an IP-based peer-to-peer network control protocol, integrates the connection management and control capabilities across digital audio networks. This enables the streaming of all types of media content among devices from different manufactures because it provides a common approach for device control. This paper describes this protocol. Each parameter of a device can be addressed with a 7-level hierarchical structure that reflects the functional layout of the device. The protocol has been implemented in many different types of networks.
- Full Text:
- Authors: Foss, Richard , Gurdan, Robby , Klinkradt, Bradley , Chigwamba, Nyasha
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/426933 , vital:72402 , https://www.aes.org/e-lib/browse.cfm?elib=16705
- Description: AES64, which is an IP-based peer-to-peer network control protocol, integrates the connection management and control capabilities across digital audio networks. This enables the streaming of all types of media content among devices from different manufactures because it provides a common approach for device control. This paper describes this protocol. Each parameter of a device can be addressed with a 7-level hierarchical structure that reflects the functional layout of the device. The protocol has been implemented in many different types of networks.
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The amaXhosa ukuthwala marriage custom in fact and fiction: a contemporary critique
- Kaschula, Russell H, Huisamen, Tim, Mostert, André M, Nosilela, Bulelwa
- Authors: Kaschula, Russell H , Huisamen, Tim , Mostert, André M , Nosilela, Bulelwa
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/68344 , vital:29241 , https://doi.org/10.1080/02572117.2013.871454
- Description: publisher version , Ukuthwala is traditionally a marriage custom within the amaXhosa culture in South Africa which permits a ‘legal abduction’ of a bride-to-be. Similar customs of ‘bridal abduction’ exist, most notably in Kyrgyzstan, where it is known as ala kachuu. Research into these customs necessitates a more innovative approach to explore the impact of this social phenomenon. In this article the authors mobilise a fictional narrative to offer a backdrop for a comparative assessment of the impact of bridal ‘legal abduction’ and assess its contemporary status and role within a multicultural society which celebrates the rights of the individual while recognising the value and importance of maintaining cultural identity and traditions. Cultural dissonance has always been characteristic of modern and post-modern societies as they strive for a workable shared ethos. However, when customs such as ‘legal abduction’ (Mtuze, 1993:50) continue under the veil of cultural rights, the wider social sensibilities and perspectives can be at odds with the maintenance of such activities where these activities contradict the rights of the individual as enshrined for example in what can be seen as a liberal South African Constitution.
- Full Text: false
- Authors: Kaschula, Russell H , Huisamen, Tim , Mostert, André M , Nosilela, Bulelwa
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/68344 , vital:29241 , https://doi.org/10.1080/02572117.2013.871454
- Description: publisher version , Ukuthwala is traditionally a marriage custom within the amaXhosa culture in South Africa which permits a ‘legal abduction’ of a bride-to-be. Similar customs of ‘bridal abduction’ exist, most notably in Kyrgyzstan, where it is known as ala kachuu. Research into these customs necessitates a more innovative approach to explore the impact of this social phenomenon. In this article the authors mobilise a fictional narrative to offer a backdrop for a comparative assessment of the impact of bridal ‘legal abduction’ and assess its contemporary status and role within a multicultural society which celebrates the rights of the individual while recognising the value and importance of maintaining cultural identity and traditions. Cultural dissonance has always been characteristic of modern and post-modern societies as they strive for a workable shared ethos. However, when customs such as ‘legal abduction’ (Mtuze, 1993:50) continue under the veil of cultural rights, the wider social sensibilities and perspectives can be at odds with the maintenance of such activities where these activities contradict the rights of the individual as enshrined for example in what can be seen as a liberal South African Constitution.
- Full Text: false
“It’s like uprooting trees”: responsive treatment for a case of complex post-traumatic stress disorder following multiple rapes
- Van der Linde, Francois, Edwards, David J A
- Authors: Van der Linde, Francois , Edwards, David J A
- Date: 2013
- Language: English
- Type: Article
- Identifier: vital:6238 , http://hdl.handle.net/10962/d1007788
- Description: This systematic case study documents 27 sessions of assessment and treatment with cognitive therapy of Bongi (23)who presented with major depression, posttraumatic stress disorder and borderline traits. Bongi had been raised in a punitive environment, had been raped three times, the first time at age 9, and had been in a series of abusive relationships. The treatment illustrates the importance of therapist responsiveness in addressing this kind of complex presentation, the importance of drawing on case formulation to guide the course of treatment and the range of different interventions that need to be incorporated into an integrative treatment of a complex case. Self-report measures of depression, anxiety and posttraumatic stress indicators provided evidence that the therapy contributed to positive changes and the qualitative therapy narrative gives details of the nature of some of those changes. Although treatment was not complete when Bongi moved away, Bongi herself judged that the therapy had been a valuable experience which had resulted in her feeling more alive, more confident, and better able to take care of herself.
- Full Text:
- Authors: Van der Linde, Francois , Edwards, David J A
- Date: 2013
- Language: English
- Type: Article
- Identifier: vital:6238 , http://hdl.handle.net/10962/d1007788
- Description: This systematic case study documents 27 sessions of assessment and treatment with cognitive therapy of Bongi (23)who presented with major depression, posttraumatic stress disorder and borderline traits. Bongi had been raised in a punitive environment, had been raped three times, the first time at age 9, and had been in a series of abusive relationships. The treatment illustrates the importance of therapist responsiveness in addressing this kind of complex presentation, the importance of drawing on case formulation to guide the course of treatment and the range of different interventions that need to be incorporated into an integrative treatment of a complex case. Self-report measures of depression, anxiety and posttraumatic stress indicators provided evidence that the therapy contributed to positive changes and the qualitative therapy narrative gives details of the nature of some of those changes. Although treatment was not complete when Bongi moved away, Bongi herself judged that the therapy had been a valuable experience which had resulted in her feeling more alive, more confident, and better able to take care of herself.
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A new broom sweeps clean: the economic and cultural value of grass brooms in the Eastern Cape Province, South Africa
- Cocks, Michelle L, Dold, Anthony P
- Authors: Cocks, Michelle L , Dold, Anthony P
- Date: 2012
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141382 , vital:37967 , DOI: 10.1080/14728028.2004.9752477
- Description: In southern Africa over the last twenty years, much attention has been given to the importance of NTFPs for rural livelihoods through their household consumption and sale. They have been classified as having either subsistence consumption or commercial values. These values are mostly related to their utilitarian functions, but recent studies show that NTFPs also hold strong cultural functions. Such cultural functions can play a role in both rural and urban livelihoods; consequently the values of NTFPs may be related to both utilitarian and cultural functions. This paper demonstrates the cultural functions of grass brooms in urban areas in South Africa and the impact of their trade on income generation in rural areas, and discusses the concept of culture as a significant factor in the understanding of the role of NTFPs in livelihoods, and their values.
- Full Text:
- Authors: Cocks, Michelle L , Dold, Anthony P
- Date: 2012
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141382 , vital:37967 , DOI: 10.1080/14728028.2004.9752477
- Description: In southern Africa over the last twenty years, much attention has been given to the importance of NTFPs for rural livelihoods through their household consumption and sale. They have been classified as having either subsistence consumption or commercial values. These values are mostly related to their utilitarian functions, but recent studies show that NTFPs also hold strong cultural functions. Such cultural functions can play a role in both rural and urban livelihoods; consequently the values of NTFPs may be related to both utilitarian and cultural functions. This paper demonstrates the cultural functions of grass brooms in urban areas in South Africa and the impact of their trade on income generation in rural areas, and discusses the concept of culture as a significant factor in the understanding of the role of NTFPs in livelihoods, and their values.
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An RTSP proxy for implementing the IPTV media function using a streaming server
- Shibeshi, Zelalem S, Terzoli, Alfredo, Bradshaw, Karen L
- Authors: Shibeshi, Zelalem S , Terzoli, Alfredo , Bradshaw, Karen L
- Date: 2012
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/429136 , vital:72562 , https://www.informatica.si/index.php/informatica/article/view/383
- Description: Multimedia content delivery in IMS, including IPTV, is handled by a separate unit, the Media Function (MF), made up of media control and media delivery units, which in the case of IPTV are the Media Control Function (MCF) and Media Delivery Function (MDF), respectively. According to the different specifications of an IMS based IPTV architecture, the User Equipment (UE) is expected to use the RTSP protocol as a media control protocol to interact with the MCF, and obtains delivery of media from the MDF using the RTP protocol. This also means that the streaming session needs to be initiated from the media controller on behalf of the user but the delivery of media is sent to the UE from the media deliverer (media server). Due both to the lack of free and open source Media Servers and the availability of free and open source Streaming Servers, the ideal choice for the delivery of multimedia services, including IPTV, by the research community is Streaming Servers. Nevertheless, because of denial of service attacks and other issues, most streaming servers do not allow a different location for the session setup request and the delivery of media in the streaming session. In other words, most streaming servers are not designed to be controlled by some other entity other than the RTSP client that consumes the media. This makes it difficult to have a separate media control unit for IPTV service in IMS if one wanted to use a streaming server as an MDF unit. So, while waiting for streaming servers to work in this manner, it is better to find a work around in order to use streaming servers to develop and test IPTV services in IMS environments. For this purpose we propose another component (an RTSP proxy and relay unit) as part of the IPTV MF and to mediate between the MCF and MDF. This unit correctly relays media control commands from the MCF to the MDF and RTP packets from the MDF to the UE. It also helps in the implementation of other streaming functionalities that are required for IPTV service delivery, but which are not implemented in the current open source streaming servers. Additional services can also be easily implemented with the help of this unit. This will facilitate the development of an IPTV service using readily available open source streaming servers and help researchers to evaluate their proposals on new services they would like to develop. In this paper we show how this RTSP proxy unit can be integrated into the Media Function of the IPTV architecture to ease the media delivery process of an IMS based IPTV service.
- Full Text:
- Authors: Shibeshi, Zelalem S , Terzoli, Alfredo , Bradshaw, Karen L
- Date: 2012
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/429136 , vital:72562 , https://www.informatica.si/index.php/informatica/article/view/383
- Description: Multimedia content delivery in IMS, including IPTV, is handled by a separate unit, the Media Function (MF), made up of media control and media delivery units, which in the case of IPTV are the Media Control Function (MCF) and Media Delivery Function (MDF), respectively. According to the different specifications of an IMS based IPTV architecture, the User Equipment (UE) is expected to use the RTSP protocol as a media control protocol to interact with the MCF, and obtains delivery of media from the MDF using the RTP protocol. This also means that the streaming session needs to be initiated from the media controller on behalf of the user but the delivery of media is sent to the UE from the media deliverer (media server). Due both to the lack of free and open source Media Servers and the availability of free and open source Streaming Servers, the ideal choice for the delivery of multimedia services, including IPTV, by the research community is Streaming Servers. Nevertheless, because of denial of service attacks and other issues, most streaming servers do not allow a different location for the session setup request and the delivery of media in the streaming session. In other words, most streaming servers are not designed to be controlled by some other entity other than the RTSP client that consumes the media. This makes it difficult to have a separate media control unit for IPTV service in IMS if one wanted to use a streaming server as an MDF unit. So, while waiting for streaming servers to work in this manner, it is better to find a work around in order to use streaming servers to develop and test IPTV services in IMS environments. For this purpose we propose another component (an RTSP proxy and relay unit) as part of the IPTV MF and to mediate between the MCF and MDF. This unit correctly relays media control commands from the MCF to the MDF and RTP packets from the MDF to the UE. It also helps in the implementation of other streaming functionalities that are required for IPTV service delivery, but which are not implemented in the current open source streaming servers. Additional services can also be easily implemented with the help of this unit. This will facilitate the development of an IPTV service using readily available open source streaming servers and help researchers to evaluate their proposals on new services they would like to develop. In this paper we show how this RTSP proxy unit can be integrated into the Media Function of the IPTV architecture to ease the media delivery process of an IMS based IPTV service.
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Baseline isotope data for Spirodela sp.: nutrient differentiation in aquatic systems
- Hill, Jaclyn M, Kaehler, Sven, Hill, Martin P
- Authors: Hill, Jaclyn M , Kaehler, Sven , Hill, Martin P
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/444502 , vital:74246 , https://doi.org/10.1016/j.watres.2012.03.063
- Description: The excessive addition of nitrogen to watersheds is recognized as one of the main causes of the global deterioration of aquatic ecosystems and an increasing number of studies have shown that δ15N signatures of macrophytes may reflect the N-loading of the system under investigation. This study investigated isotopic equilibration rates and concentration level effects of KNO3 and cow manure nutrient solutions on the δ15N and δ13C signatures, C/N ratios, % N and % C of Spirodela sp. over time, to determine the feasibility of their use in monitoring anthropogenic N-loading in freshwater systems. Spirodela δ15N signatures clearly distinguished between nutrient types within 2 days of introduction, with plants grown in KNO3 showing extremely depleted δ15N values (−15.00 to −12.00‰) compared to those growing in cow manure (14.00–18.00‰). Isotopic equilibration rates could not be determined with certainty, but plant isotopic differentiation between nutrient regimes became apparent after 2 days and started to equilibrate by day 4. Concentration level effects were also apparent, with Spirodela tissue displaying more depleted and enriched δ15N values in higher concentrations of KNO3 and cow manure respectively.
- Full Text:
- Authors: Hill, Jaclyn M , Kaehler, Sven , Hill, Martin P
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/444502 , vital:74246 , https://doi.org/10.1016/j.watres.2012.03.063
- Description: The excessive addition of nitrogen to watersheds is recognized as one of the main causes of the global deterioration of aquatic ecosystems and an increasing number of studies have shown that δ15N signatures of macrophytes may reflect the N-loading of the system under investigation. This study investigated isotopic equilibration rates and concentration level effects of KNO3 and cow manure nutrient solutions on the δ15N and δ13C signatures, C/N ratios, % N and % C of Spirodela sp. over time, to determine the feasibility of their use in monitoring anthropogenic N-loading in freshwater systems. Spirodela δ15N signatures clearly distinguished between nutrient types within 2 days of introduction, with plants grown in KNO3 showing extremely depleted δ15N values (−15.00 to −12.00‰) compared to those growing in cow manure (14.00–18.00‰). Isotopic equilibration rates could not be determined with certainty, but plant isotopic differentiation between nutrient regimes became apparent after 2 days and started to equilibrate by day 4. Concentration level effects were also apparent, with Spirodela tissue displaying more depleted and enriched δ15N values in higher concentrations of KNO3 and cow manure respectively.
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Fig wasps as vectors of mites and nematodes
- Jauharlina, J, Lindquist, E E, Quinnell, R J, Compton, Stephen G, Robertson, Hamish G
- Authors: Jauharlina, J , Lindquist, E E , Quinnell, R J , Compton, Stephen G , Robertson, Hamish G
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/452076 , vital:75101 , https://hdl.handle.net/10520/EJC119300
- Description: Females of the pollinator fig wasp Elisabethiella baijnathi Wiebes carry mites (Tarsonemella sp. nr. africanus) and nematodes (Parasitodiplogaster sp.) between figs of Ficus burtt-davyi in Grahamstown, South Africa. The mites are phoretic on the outside of the wasps and phytophagous, feeding on galled flowers. The nematodes are transported inside the wasps and eventually eat them. Both mites and nematodes were present throughout the year. The prevalence (fig occupancy rates) of mites and nematodes in different crops ranged between zero and 100 %. Crop size did not influence the prevalence of either mites or nematodes. Contrasting dispersion patterns and relationships with fig wasp foundress numbers indicate that the mites, but not the nematodes, disperse between figs after being carried there by the pollinators, and they may also utilize non-pollinating fig wasps as vectors.
- Full Text:
- Authors: Jauharlina, J , Lindquist, E E , Quinnell, R J , Compton, Stephen G , Robertson, Hamish G
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/452076 , vital:75101 , https://hdl.handle.net/10520/EJC119300
- Description: Females of the pollinator fig wasp Elisabethiella baijnathi Wiebes carry mites (Tarsonemella sp. nr. africanus) and nematodes (Parasitodiplogaster sp.) between figs of Ficus burtt-davyi in Grahamstown, South Africa. The mites are phoretic on the outside of the wasps and phytophagous, feeding on galled flowers. The nematodes are transported inside the wasps and eventually eat them. Both mites and nematodes were present throughout the year. The prevalence (fig occupancy rates) of mites and nematodes in different crops ranged between zero and 100 %. Crop size did not influence the prevalence of either mites or nematodes. Contrasting dispersion patterns and relationships with fig wasp foundress numbers indicate that the mites, but not the nematodes, disperse between figs after being carried there by the pollinators, and they may also utilize non-pollinating fig wasps as vectors.
- Full Text: