Mechanisms generating biological diversity in the genus Platypleura Amyot & Serville, 1843 (Hemiptera: Cicadidae) in southern Africa: implications of a preliminary molecular phylogeny
- Villet, Martin H, Barker, Nigel P, Lunt, N
- Authors: Villet, Martin H , Barker, Nigel P , Lunt, N
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6554 , http://hdl.handle.net/10962/d1006012
- Description: Truly understanding biological diversity requires a move from descriptive studies to mechanistic interpretations based on comparative biology and a thorough recognition of the natural history of the focal organisms. A useful step in such comparative studies is the generation of a phylogeny, so that one can assess the phylogenetic independence of the focal taxa and trace the evolutionary significance of their characteristics. As a preliminary to such studies on the platypleurine cicada genus Platypleura, we sequenced 498 bases of the cytochrome oxidase I (COI) gene from thirteen African species. To circumvent problems with outgroup selection, we also included sequences from representatives of the platypleurine genera Brevisiana, Capcicada, Munza, Oxypleura, Severiana, and Systophlochius, all of the subtribe Platypleuriti, and two species of the genus Ugada, of the subtribe Hainanosemiiti. The resulting phylogenies support the synonymization of the monotypic genus Systophlochius with the widespread, speciose genus Platypleura; confirm the placement of Platypleura sp. 7 in that genus; and confirm the independence of Capcicada and Platypleura. Although the preliminary phylogeny lacks strong support at many nodes, it suggests that three radiations of Platypleura have occurred in southern Africa and that there was progressive southward speciation of these radiations. A novel modification of the ancestral area analysis further suggests that the group has an ancestral association with acacias but there were five independent speciation events associated with host- switching. These insights can be summarized by a general hypothesis that the mechanisms underlying platypleurine biodiversity in southern Africa involve two ancient vicariance events and subsequent speciation by vicariance, switching of plant associations, and changes of habitat preferences. We offer this example to illustrate how analysis of preliminary data can help to generate hypotheticodeductive research hypotheses, to provoke interest in testing these hypotheses, and to illustrate the utility of phylogenies beyond systematics.
- Full Text:
- Authors: Villet, Martin H , Barker, Nigel P , Lunt, N
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6554 , http://hdl.handle.net/10962/d1006012
- Description: Truly understanding biological diversity requires a move from descriptive studies to mechanistic interpretations based on comparative biology and a thorough recognition of the natural history of the focal organisms. A useful step in such comparative studies is the generation of a phylogeny, so that one can assess the phylogenetic independence of the focal taxa and trace the evolutionary significance of their characteristics. As a preliminary to such studies on the platypleurine cicada genus Platypleura, we sequenced 498 bases of the cytochrome oxidase I (COI) gene from thirteen African species. To circumvent problems with outgroup selection, we also included sequences from representatives of the platypleurine genera Brevisiana, Capcicada, Munza, Oxypleura, Severiana, and Systophlochius, all of the subtribe Platypleuriti, and two species of the genus Ugada, of the subtribe Hainanosemiiti. The resulting phylogenies support the synonymization of the monotypic genus Systophlochius with the widespread, speciose genus Platypleura; confirm the placement of Platypleura sp. 7 in that genus; and confirm the independence of Capcicada and Platypleura. Although the preliminary phylogeny lacks strong support at many nodes, it suggests that three radiations of Platypleura have occurred in southern Africa and that there was progressive southward speciation of these radiations. A novel modification of the ancestral area analysis further suggests that the group has an ancestral association with acacias but there were five independent speciation events associated with host- switching. These insights can be summarized by a general hypothesis that the mechanisms underlying platypleurine biodiversity in southern Africa involve two ancient vicariance events and subsequent speciation by vicariance, switching of plant associations, and changes of habitat preferences. We offer this example to illustrate how analysis of preliminary data can help to generate hypotheticodeductive research hypotheses, to provoke interest in testing these hypotheses, and to illustrate the utility of phylogenies beyond systematics.
- Full Text:
Metus in the Roman law of obligations
- Authors: Glover, Graham B
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6336 , http://hdl.handle.net/10962/d1012401
- Description: [From the introduction]: An entire title of book four of Justinian’s Digest is devoted to explaining the doctrine of metus as it was understood at the time of the codification of the Roman law. That title begins with the following statement: "The praetor says: 'I will not hold valid what has been done under duress.'" This unequivocal statement of legal principle illustrates, in very general terms, that by the time the Corpus Iuris Civilis was compiled, the Romans disapproved of persons using threats to inspire the creation of legal obligations, and that it was possible to avoid the legal consequences of an obligation because it was induced by metus. The Corpus Iuris Civilis remains our most valuable source of authority with regard to how duress cases were treated in Roman times. But the relevant textual sources pose some fundamental difficulties. Far from containing a coherent, structured analysis of the law, the relevant passages in fact amount to a jigsaw-puzzle of uncoordinated, haphazard, and occasionally contradictory legal propositions
- Full Text:
- Authors: Glover, Graham B
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6336 , http://hdl.handle.net/10962/d1012401
- Description: [From the introduction]: An entire title of book four of Justinian’s Digest is devoted to explaining the doctrine of metus as it was understood at the time of the codification of the Roman law. That title begins with the following statement: "The praetor says: 'I will not hold valid what has been done under duress.'" This unequivocal statement of legal principle illustrates, in very general terms, that by the time the Corpus Iuris Civilis was compiled, the Romans disapproved of persons using threats to inspire the creation of legal obligations, and that it was possible to avoid the legal consequences of an obligation because it was induced by metus. The Corpus Iuris Civilis remains our most valuable source of authority with regard to how duress cases were treated in Roman times. But the relevant textual sources pose some fundamental difficulties. Far from containing a coherent, structured analysis of the law, the relevant passages in fact amount to a jigsaw-puzzle of uncoordinated, haphazard, and occasionally contradictory legal propositions
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Miscarriage : an exploration of women's experience : a qualitative study
- Watson, Julia Margretha Garland
- Authors: Watson, Julia Margretha Garland
- Date: 2004
- Subjects: Miscarriage -- Psychological aspects , Loss (Psychology) , Bereavement -- Psychological aspects , Infants -- Death -- Psychological aspects , Fetal death -- Psychological aspects
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:688 , http://hdl.handle.net/10962/d1003735 , Miscarriage -- Psychological aspects , Loss (Psychology) , Bereavement -- Psychological aspects , Infants -- Death -- Psychological aspects , Fetal death -- Psychological aspects
- Description: Miscarriage can result in significant psychological distress to women. However, many women experience a cultural norm which attributes minimal meaning to the loss. This is reflected in the lack of support experienced from interaction with both medical professionals and those within the individual's social context. This qualitative study reports on the unique experiences of six South African women; their experience of other's reactions to their miscarriage; and their recommendations for better coping with the experience. Data was gathered using one semi-structured interview. Data reduction and analysis followed using a four-stage model of thematic outlines, coding, and comparisons (Marshall and Rossman 1998:152; Marck and Field 1994:9). The objective of the analysis sought to compare the themes generated by the actual data collected with those described in other studies. In this way the findings of the study are generalisable to a larger population and allows for a greater sense of representivity (Silverman 1994:160). Comparisons were made between the women's experiences, as told by them, and Bowles' identification of the Four Domains of Miscarriage Distress Symptoms (2000). The women viewed psychological support as essential in the process of coping; and acknowledgement of their loss as being the loss of a child, as a strong determinant of coming to terms with the loss. A strong need to have support from other women who had shared the experience was voiced. Recommendations for improved intervention are made. In short the core recommendations are: the provision of patient follow-up; the provision of written material; and, specialist training for those working in the area of pregnancy loss.
- Full Text:
- Authors: Watson, Julia Margretha Garland
- Date: 2004
- Subjects: Miscarriage -- Psychological aspects , Loss (Psychology) , Bereavement -- Psychological aspects , Infants -- Death -- Psychological aspects , Fetal death -- Psychological aspects
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:688 , http://hdl.handle.net/10962/d1003735 , Miscarriage -- Psychological aspects , Loss (Psychology) , Bereavement -- Psychological aspects , Infants -- Death -- Psychological aspects , Fetal death -- Psychological aspects
- Description: Miscarriage can result in significant psychological distress to women. However, many women experience a cultural norm which attributes minimal meaning to the loss. This is reflected in the lack of support experienced from interaction with both medical professionals and those within the individual's social context. This qualitative study reports on the unique experiences of six South African women; their experience of other's reactions to their miscarriage; and their recommendations for better coping with the experience. Data was gathered using one semi-structured interview. Data reduction and analysis followed using a four-stage model of thematic outlines, coding, and comparisons (Marshall and Rossman 1998:152; Marck and Field 1994:9). The objective of the analysis sought to compare the themes generated by the actual data collected with those described in other studies. In this way the findings of the study are generalisable to a larger population and allows for a greater sense of representivity (Silverman 1994:160). Comparisons were made between the women's experiences, as told by them, and Bowles' identification of the Four Domains of Miscarriage Distress Symptoms (2000). The women viewed psychological support as essential in the process of coping; and acknowledgement of their loss as being the loss of a child, as a strong determinant of coming to terms with the loss. A strong need to have support from other women who had shared the experience was voiced. Recommendations for improved intervention are made. In short the core recommendations are: the provision of patient follow-up; the provision of written material; and, specialist training for those working in the area of pregnancy loss.
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Modelling and rendering techniques for african hairstyles
- Patrick, Deborah, Bangay, Shaun D, Lobb, Adele
- Authors: Patrick, Deborah , Bangay, Shaun D , Lobb, Adele
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/432905 , vital:72911 , https://doi.org/10.1145/1029949.1029971
- Description: We develop or enhance hair modelling and rendering techniques to produce three different forms of hair commonly found in African hairstyles. The forms of hair are natural curly hair, straightened hair, and braids or twists of hair. We use an implicit model, implemented as a series of textured layers to represent curly hair. Straightened hair is represented explicitly, and mod-elled by defining and replicating a few control hairs. Braids and twists are implemented as textured generalized cylinders. A synthesis of existing hair illumination models is used as a basis for an African hair illumination model. Parameter values to match African hair characteristics are discussed. A number of complete African hairstyles are shown, demonstrating that the techniques can be used to model and render African hair successfully.
- Full Text:
- Authors: Patrick, Deborah , Bangay, Shaun D , Lobb, Adele
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/432905 , vital:72911 , https://doi.org/10.1145/1029949.1029971
- Description: We develop or enhance hair modelling and rendering techniques to produce three different forms of hair commonly found in African hairstyles. The forms of hair are natural curly hair, straightened hair, and braids or twists of hair. We use an implicit model, implemented as a series of textured layers to represent curly hair. Straightened hair is represented explicitly, and mod-elled by defining and replicating a few control hairs. Braids and twists are implemented as textured generalized cylinders. A synthesis of existing hair illumination models is used as a basis for an African hair illumination model. Parameter values to match African hair characteristics are discussed. A number of complete African hairstyles are shown, demonstrating that the techniques can be used to model and render African hair successfully.
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Models of Internet Connectivity in Previously Disadvantaged Secondary Schools in the Eastern Cape
- Brandt, Ingrid, Terzoli, Alfredo, Hodgkinson-Williams, Cheryl
- Authors: Brandt, Ingrid , Terzoli, Alfredo , Hodgkinson-Williams, Cheryl
- Date: 2004
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/427602 , vital:72450 , https://d1wqtxts1xzle7.cloudfront.net/43383861/Models_of_Internet_Connectivity_in_Previ20160305-2534-1salhbh-libre.pdf?1457175561=andresponse-content-disposi-tion=inline%3B+filename%3DModels_of_Internet_Connectivity_in_Previ.pdfandExpires=1714994733andSignature=AS-VDG85ZQPZzWwvz3ITck4K9JIs4zA2bCzFW9LLCYPj9aI~gA4qSOmURIkQz4VE2ZiOrjWHDyeebZyoYs50SPW8~IF31aXPoz8MFAY~qz0DgIAVCNF5k7vXqnCxmnuE5zMEjnxxkNigthvwSD4yDrpJ0Hy5VdN20~3p1j0E9N7zaiTPexGvrH85p3k~bb4Mht00QdltgVGO3tcqiAA9-eskZ--mS7X1acD3ehhXVG7hGVxLqq6TsjdEWOKh6Z4Gkt0Utdcx84zWAkC56yN8GoHwTbxt1DkjMOuatLhWppfMLNQPy6hNYga9GNq-0dalbisbJ1G-Nrbez0O0w2w8EA__andKey-Pair-Id=APKAJLOHF5GGSLRBV4ZA
- Description: Computers are increasingly considered a valuable tool in Education, not only for the purpose of administration but also for teaching and learning. This project aims to model Internet connectivity to previously disadvan-taged schools in the Eastern Cape by investigating known networking technologies in the context of such schools. We look at wired and wireless technologies, while bearing in mind issues such as cost, organisation ca-pacity and such like.
- Full Text:
- Authors: Brandt, Ingrid , Terzoli, Alfredo , Hodgkinson-Williams, Cheryl
- Date: 2004
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/427602 , vital:72450 , https://d1wqtxts1xzle7.cloudfront.net/43383861/Models_of_Internet_Connectivity_in_Previ20160305-2534-1salhbh-libre.pdf?1457175561=andresponse-content-disposi-tion=inline%3B+filename%3DModels_of_Internet_Connectivity_in_Previ.pdfandExpires=1714994733andSignature=AS-VDG85ZQPZzWwvz3ITck4K9JIs4zA2bCzFW9LLCYPj9aI~gA4qSOmURIkQz4VE2ZiOrjWHDyeebZyoYs50SPW8~IF31aXPoz8MFAY~qz0DgIAVCNF5k7vXqnCxmnuE5zMEjnxxkNigthvwSD4yDrpJ0Hy5VdN20~3p1j0E9N7zaiTPexGvrH85p3k~bb4Mht00QdltgVGO3tcqiAA9-eskZ--mS7X1acD3ehhXVG7hGVxLqq6TsjdEWOKh6Z4Gkt0Utdcx84zWAkC56yN8GoHwTbxt1DkjMOuatLhWppfMLNQPy6hNYga9GNq-0dalbisbJ1G-Nrbez0O0w2w8EA__andKey-Pair-Id=APKAJLOHF5GGSLRBV4ZA
- Description: Computers are increasingly considered a valuable tool in Education, not only for the purpose of administration but also for teaching and learning. This project aims to model Internet connectivity to previously disadvan-taged schools in the Eastern Cape by investigating known networking technologies in the context of such schools. We look at wired and wireless technologies, while bearing in mind issues such as cost, organisation ca-pacity and such like.
- Full Text:
Molecular chaperones in biology, medicine and protein biotechnology
- Boshoff, Aileen, Nicoll, William S, Hennessy, Fritha, Ludewig, M H, Daniel, Sheril, Modisakeng, Keoagile W, Shonhai, Addmore, McNamara, Caryn, Bradley, Graeme, Blatch, Gregory L
- Authors: Boshoff, Aileen , Nicoll, William S , Hennessy, Fritha , Ludewig, M H , Daniel, Sheril , Modisakeng, Keoagile W , Shonhai, Addmore , McNamara, Caryn , Bradley, Graeme , Blatch, Gregory L
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6457 , http://hdl.handle.net/10962/d1004479
- Description: Molecular chaperones consist of several highly conserved families of proteins, many of which consist of heat shock proteins. The primary function of molecular chaperones is to facilitate the folding or refolding of proteins, and therefore they play an important role in diverse cellular processes including protein synthesis, protein translocation, and the refolding or degradation of proteins after cell stress. Cells are often exposed to different stressors, resulting in protein misfolding and aggregation. It is now well established that the levels of certain molecular chaperones are elevated during stress to provide protection to the cell. The focus of this review is on the impact of molecular chaperones in biology, medicine and protein biotechnology, and thus covers both fundamental and applied aspects of chaperone biology. Attention is paid to the functions and applications of molecular chaperones from bacterial and eukaryotic cells, focusing on the heat shock proteins 90 (Hsp90), 70 (Hsp70) and 40 (Hsp40) classes of chaperones, respectively. The role of these classes of chaperones in human diseases is discussed, as well as the parts played by chaperones produced by the causative agents of malaria and trypanosomiasis. Recent advances have seen the application of chaperones in improving the yields of a particular target protein in recombinant protein production. The prospects for the targeted use of molecular chaperones for the over-production of recombinant proteins is critically reviewed, and current research on these chaperones at Rhodes University is also discussed.
- Full Text:
- Authors: Boshoff, Aileen , Nicoll, William S , Hennessy, Fritha , Ludewig, M H , Daniel, Sheril , Modisakeng, Keoagile W , Shonhai, Addmore , McNamara, Caryn , Bradley, Graeme , Blatch, Gregory L
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6457 , http://hdl.handle.net/10962/d1004479
- Description: Molecular chaperones consist of several highly conserved families of proteins, many of which consist of heat shock proteins. The primary function of molecular chaperones is to facilitate the folding or refolding of proteins, and therefore they play an important role in diverse cellular processes including protein synthesis, protein translocation, and the refolding or degradation of proteins after cell stress. Cells are often exposed to different stressors, resulting in protein misfolding and aggregation. It is now well established that the levels of certain molecular chaperones are elevated during stress to provide protection to the cell. The focus of this review is on the impact of molecular chaperones in biology, medicine and protein biotechnology, and thus covers both fundamental and applied aspects of chaperone biology. Attention is paid to the functions and applications of molecular chaperones from bacterial and eukaryotic cells, focusing on the heat shock proteins 90 (Hsp90), 70 (Hsp70) and 40 (Hsp40) classes of chaperones, respectively. The role of these classes of chaperones in human diseases is discussed, as well as the parts played by chaperones produced by the causative agents of malaria and trypanosomiasis. Recent advances have seen the application of chaperones in improving the yields of a particular target protein in recombinant protein production. The prospects for the targeted use of molecular chaperones for the over-production of recombinant proteins is critically reviewed, and current research on these chaperones at Rhodes University is also discussed.
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Moral reform and the desiderata of responses to wrongdoing: the production of a "morally autonomous person freely attached to the good"
- Authors: Waller, Heath Frederick
- Date: 2004 , 2013-06-14
- Subjects: Victims of crimes -- Attitudes , Criminals -- Rehabilitation , Punishment -- Psychological aspects , Social ethics , Punishment
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2730 , http://hdl.handle.net/10962/d1003805 , Victims of crimes -- Attitudes , Criminals -- Rehabilitation , Punishment -- Psychological aspects , Social ethics , Punishment
- Description: Moral reform is a neglected response to wrongdoing that has been incorrectly portrayed as a practice involving illegitimate treatment of wrongdoers and as totally unsatisfying to those theorists advocating backward-looking practices such as retributive punishment. A clear explanation of the ethical legitimacy and practical necessity of the reformative techniques moral reform involves has been missed, and this paper details the design of moral reform proper in order to fill this gap in punishment theory. The moral reform of an offender is identified as a desideratum of responses to wrongdoing and it is explained what moral reform ought to entail. The claim that moral reform qualifies as the overriding aim of responses to wrongdoing is argued for on the grounds that this practice is capable of achieving all the established ends of responses to wrongdoing. The legitimate desiderata of our practices are identified as those usually selected as the ends of punishment practices, and moral reform must accomplish these if it is to be accepted. Moral reform is shown to realise the goals of punishments as the fortunate effects of what is done to achieve an offender's moral improvement and of what reformees do in taking responsibility for their actions. The suffering involved in moral reform receives particular emphasis since the practice will never satisfy unless it accommodates the widely-held intuition that the offender must suffer sufficiently as a consequence of his wrongdoing. Moral reform is further portrayed as the most meaningful practice for its ability to satisfy the appropriate needs and desires victims have in response to their victimization. A central claim of the thesis is that moral reform best serves the victim, since it most effectively relieves the victim's emotional responses to wrongdoing and is as adept as punishment at the expression of these same emotions. Reformers advocate a constructive response to wrongdoing that benefits all affected parties. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Authors: Waller, Heath Frederick
- Date: 2004 , 2013-06-14
- Subjects: Victims of crimes -- Attitudes , Criminals -- Rehabilitation , Punishment -- Psychological aspects , Social ethics , Punishment
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2730 , http://hdl.handle.net/10962/d1003805 , Victims of crimes -- Attitudes , Criminals -- Rehabilitation , Punishment -- Psychological aspects , Social ethics , Punishment
- Description: Moral reform is a neglected response to wrongdoing that has been incorrectly portrayed as a practice involving illegitimate treatment of wrongdoers and as totally unsatisfying to those theorists advocating backward-looking practices such as retributive punishment. A clear explanation of the ethical legitimacy and practical necessity of the reformative techniques moral reform involves has been missed, and this paper details the design of moral reform proper in order to fill this gap in punishment theory. The moral reform of an offender is identified as a desideratum of responses to wrongdoing and it is explained what moral reform ought to entail. The claim that moral reform qualifies as the overriding aim of responses to wrongdoing is argued for on the grounds that this practice is capable of achieving all the established ends of responses to wrongdoing. The legitimate desiderata of our practices are identified as those usually selected as the ends of punishment practices, and moral reform must accomplish these if it is to be accepted. Moral reform is shown to realise the goals of punishments as the fortunate effects of what is done to achieve an offender's moral improvement and of what reformees do in taking responsibility for their actions. The suffering involved in moral reform receives particular emphasis since the practice will never satisfy unless it accommodates the widely-held intuition that the offender must suffer sufficiently as a consequence of his wrongdoing. Moral reform is further portrayed as the most meaningful practice for its ability to satisfy the appropriate needs and desires victims have in response to their victimization. A central claim of the thesis is that moral reform best serves the victim, since it most effectively relieves the victim's emotional responses to wrongdoing and is as adept as punishment at the expression of these same emotions. Reformers advocate a constructive response to wrongdoing that benefits all affected parties. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
Multiprotocol control of networked home entertainment devices
- Authors: Siebörger, David Robert
- Date: 2004
- Subjects: Home entertainment systems , Home video systems
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4642 , http://hdl.handle.net/10962/d1006585 , Home entertainment systems , Home video systems
- Description: Networks will soon connect a wide range of computing devices within the home. Amongst those devices will be home entertainment devices. Remote control over the network will be a key application for networked entertainment devices, and requires a protocol for communication understood by both controller and controlled device. Devices capable of communication using multiple control protocols will be compatible with a wider range of controllers than those which implement only one control protocol. This work examines home networks and a number of control protocols. The implementations of the UPnP and AV/C protocols for an AV receiver are described. The issues involved in the concurrent use of multiple control protocols to control a device are considered, possible methods of concurrent control discussed, and a solution which simulates virtual copies of the device is implemented and tested.
- Full Text:
- Authors: Siebörger, David Robert
- Date: 2004
- Subjects: Home entertainment systems , Home video systems
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4642 , http://hdl.handle.net/10962/d1006585 , Home entertainment systems , Home video systems
- Description: Networks will soon connect a wide range of computing devices within the home. Amongst those devices will be home entertainment devices. Remote control over the network will be a key application for networked entertainment devices, and requires a protocol for communication understood by both controller and controlled device. Devices capable of communication using multiple control protocols will be compatible with a wider range of controllers than those which implement only one control protocol. This work examines home networks and a number of control protocols. The implementations of the UPnP and AV/C protocols for an AV receiver are described. The issues involved in the concurrent use of multiple control protocols to control a device are considered, possible methods of concurrent control discussed, and a solution which simulates virtual copies of the device is implemented and tested.
- Full Text:
Music and (post)colonialism : the dialectics of choral culture on a South African frontier
- Authors: Olwage, Grant
- Date: 2004
- Subjects: Choral music -- South Africa -- History Black people -- South Africa -- Music -- History and criticism Bokwe, John Knox, 1855-1922
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2679 , http://hdl.handle.net/10962/d1007717
- Description: This thesis explores the genesis of black choralism in late-nineteenth-century colonial South Africa, attending specifically to its dialectic with metropolitan Victorian choralism. In two introductory historiographic chapters I outline the political-narrative strategies by which both Victorian and black South African choralism have been elided from music histories. Part 1 gives an account of the "structures" within and through which choralism functioned as a practice of colonisation, as "internal colonialism" in Britain and evangelical colonialism in the eastern Cape Colony. In chapter 1 I suggest that the religious contexts within which choralism operated, including the music theoretical construction of the tonic sol-fa notation and method as "natural", and the "scientific" musicalisation of race, constituted conditions for the foreign mission's embrace of choralism. The second chapter explores further such affinities, tracing sol-fa choralism's institutional affiliations with nineteenth-century "reform" movements, and suggesting that sol-fa's practices worked in fulfilment of core reformist concerns such as "industry" and literacy. Throughout, the thesis explores how the categories of class and race functioned interchangeably in the colonial imagination. Chapter 3 charts this relationship in the terrain of music education; notations, for instance, which were classed in Britain, became racialised in colonial South Africa. In particular I show that black music education operated within colonial racial discourses. Chapter 4 is a reading of Victorian choralism as a "discipline", interpreting choral performance practice and choral music itself as disciplinary acts which complemented the political contexts in which choralism operated. Part 1, in short, explores how popular choralism operated within and as dominant politicking. In part 2 I turn to the black reception of Victorian choralism in composition and performance. The fifth chapter examines the compositional discourse of early black choral music, focussing on the work of John Knox Bokwe (1855-1922). Through a detailed account of several of Bokwe's works and their metropolitan sources, particularly late-nineteenth century gospel hymnody, I show that Bokwe's compositional practice enacted a politics that became anticolonial, and that early black choral music became "black" in its reception. I conclude that ethno/musicological claims that early black choral music contains "African" musical content conflate "race" and culture under a double imperative: in the names of a decolonising politics and a postcolonial epistemology in which hybridity as resistance is racialised. The final chapter explores how "the voice" was crucial to identity politics in the Victorian world, an object that was classed and racialised. Proceeding from the black reception of choral voice training, I attempt to outline the beginnings of a social history of the black choral voice, as well as analyse the sonic content of that voice through an approach I call a "phonetics of timbre".
- Full Text:
- Authors: Olwage, Grant
- Date: 2004
- Subjects: Choral music -- South Africa -- History Black people -- South Africa -- Music -- History and criticism Bokwe, John Knox, 1855-1922
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2679 , http://hdl.handle.net/10962/d1007717
- Description: This thesis explores the genesis of black choralism in late-nineteenth-century colonial South Africa, attending specifically to its dialectic with metropolitan Victorian choralism. In two introductory historiographic chapters I outline the political-narrative strategies by which both Victorian and black South African choralism have been elided from music histories. Part 1 gives an account of the "structures" within and through which choralism functioned as a practice of colonisation, as "internal colonialism" in Britain and evangelical colonialism in the eastern Cape Colony. In chapter 1 I suggest that the religious contexts within which choralism operated, including the music theoretical construction of the tonic sol-fa notation and method as "natural", and the "scientific" musicalisation of race, constituted conditions for the foreign mission's embrace of choralism. The second chapter explores further such affinities, tracing sol-fa choralism's institutional affiliations with nineteenth-century "reform" movements, and suggesting that sol-fa's practices worked in fulfilment of core reformist concerns such as "industry" and literacy. Throughout, the thesis explores how the categories of class and race functioned interchangeably in the colonial imagination. Chapter 3 charts this relationship in the terrain of music education; notations, for instance, which were classed in Britain, became racialised in colonial South Africa. In particular I show that black music education operated within colonial racial discourses. Chapter 4 is a reading of Victorian choralism as a "discipline", interpreting choral performance practice and choral music itself as disciplinary acts which complemented the political contexts in which choralism operated. Part 1, in short, explores how popular choralism operated within and as dominant politicking. In part 2 I turn to the black reception of Victorian choralism in composition and performance. The fifth chapter examines the compositional discourse of early black choral music, focussing on the work of John Knox Bokwe (1855-1922). Through a detailed account of several of Bokwe's works and their metropolitan sources, particularly late-nineteenth century gospel hymnody, I show that Bokwe's compositional practice enacted a politics that became anticolonial, and that early black choral music became "black" in its reception. I conclude that ethno/musicological claims that early black choral music contains "African" musical content conflate "race" and culture under a double imperative: in the names of a decolonising politics and a postcolonial epistemology in which hybridity as resistance is racialised. The final chapter explores how "the voice" was crucial to identity politics in the Victorian world, an object that was classed and racialised. Proceeding from the black reception of choral voice training, I attempt to outline the beginnings of a social history of the black choral voice, as well as analyse the sonic content of that voice through an approach I call a "phonetics of timbre".
- Full Text:
Mycorrhizal status of indigenous tree species in a forest biome of the Eastern Cape, South Africa
- Hawley, Greer L, Dames, Joanna F
- Authors: Hawley, Greer L , Dames, Joanna F
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6458 , http://hdl.handle.net/10962/d1005774
- Description: Mycorrhizal fungi are intimately associated with plant roots, affecting plant growth, health and increasing the plants' tolerance to environmental stress. Several mycorrhizal types are recognized based primarily on morphological characteristics within plant roots. When considering propagation and management of an indigenous plant species, it is essential to know its mycorrhizal status. Root samples from 17 tree species common to the pockets of forest in the Eastern Cape province, and representing the families Rubiaceae, Scrophulariaceae, Oleaceae, Podocarpaceae, Myrsinaceae, Anacardiaceae, Caesalpinoideae, Papilionoideae, Rutaceae, Meliaceae, Celastraceae, Flacouticeae and Ebenaceae, were sampled and examined for mycorrhizal colonization. Microscopic examination of all the species produced evidence of morphological structures indicative of endomycorrhizal associations as indicated by the presence of intercellular hyphae combined with vesicles, arbuscules or hyphal coils. Hyphal coils (also known as Paris-type associations) appeared to be abundant, especially within the Cassine genus. Arbuscules (also known as Arum-type associations) were scarce but sometimes present, and vesicles were prolific in Olea capensis. Most of the tree species examined have been assigned arbuscular mycorrhizal status. No ectomycorrhizal associations were recorded
- Full Text:
- Authors: Hawley, Greer L , Dames, Joanna F
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6458 , http://hdl.handle.net/10962/d1005774
- Description: Mycorrhizal fungi are intimately associated with plant roots, affecting plant growth, health and increasing the plants' tolerance to environmental stress. Several mycorrhizal types are recognized based primarily on morphological characteristics within plant roots. When considering propagation and management of an indigenous plant species, it is essential to know its mycorrhizal status. Root samples from 17 tree species common to the pockets of forest in the Eastern Cape province, and representing the families Rubiaceae, Scrophulariaceae, Oleaceae, Podocarpaceae, Myrsinaceae, Anacardiaceae, Caesalpinoideae, Papilionoideae, Rutaceae, Meliaceae, Celastraceae, Flacouticeae and Ebenaceae, were sampled and examined for mycorrhizal colonization. Microscopic examination of all the species produced evidence of morphological structures indicative of endomycorrhizal associations as indicated by the presence of intercellular hyphae combined with vesicles, arbuscules or hyphal coils. Hyphal coils (also known as Paris-type associations) appeared to be abundant, especially within the Cassine genus. Arbuscules (also known as Arum-type associations) were scarce but sometimes present, and vesicles were prolific in Olea capensis. Most of the tree species examined have been assigned arbuscular mycorrhizal status. No ectomycorrhizal associations were recorded
- Full Text:
Neural network-based ionospheric modelling over the South African region
- McKinnell, Lee-Anne, Poole, Allon W V
- Authors: McKinnell, Lee-Anne , Poole, Allon W V
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6795 , http://hdl.handle.net/10962/d1003839
- Description: During the past decade, South African scientists have pioneered research in the field of ionospheric modelling using the technique of neural networks (NNs). Global ionospheric models have always been insufficient for the South African region owing to an historical paucity of available data. Within the past 10 years, however, three new ionospheric sounders have been installed locally and are operating continuously. These sounders are located at Grahamstown (33.3°S, 26.5°E), Louisvale (28.5°S, 21.2°E) and Madimbo (22.4°S, 30.9°E). The addition of a modern sounder at Grahamstown enlarged the ionospheric database for this station to 30 years, making this archive a considerable asset for ionospheric research. Quality control and online availability of the data has also added to its attraction. An important requirement for empirical modelling, but especially for employing NNs, is a large database describing the history of the relationship between the ionosphere and the geophysical parameters that define its behaviour. This review describes the path of South African ionospheric modelling over the past 10 years, the role of NNs in this development, the international collaborations that have arisen from this, and the future of ionospheric modelling in South Africa.
- Full Text:
- Authors: McKinnell, Lee-Anne , Poole, Allon W V
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6795 , http://hdl.handle.net/10962/d1003839
- Description: During the past decade, South African scientists have pioneered research in the field of ionospheric modelling using the technique of neural networks (NNs). Global ionospheric models have always been insufficient for the South African region owing to an historical paucity of available data. Within the past 10 years, however, three new ionospheric sounders have been installed locally and are operating continuously. These sounders are located at Grahamstown (33.3°S, 26.5°E), Louisvale (28.5°S, 21.2°E) and Madimbo (22.4°S, 30.9°E). The addition of a modern sounder at Grahamstown enlarged the ionospheric database for this station to 30 years, making this archive a considerable asset for ionospheric research. Quality control and online availability of the data has also added to its attraction. An important requirement for empirical modelling, but especially for employing NNs, is a large database describing the history of the relationship between the ionosphere and the geophysical parameters that define its behaviour. This review describes the path of South African ionospheric modelling over the past 10 years, the role of NNs in this development, the international collaborations that have arisen from this, and the future of ionospheric modelling in South Africa.
- Full Text:
Nuclear translocation of the Hsp70/Hsp90 organizing protein mSTI1 is regulated by cell cycle kinases
- Longshaw, Victoria M, Chapple, J Paul, Cheetham, Michael E, Blatch, Gregory L
- Authors: Longshaw, Victoria M , Chapple, J Paul , Cheetham, Michael E , Blatch, Gregory L
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6488 , http://hdl.handle.net/10962/d1006271 , https://dx.doi.org/10.1242/jcs.00905
- Description: The co-chaperone murine stress-inducible protein 1 (mSTI1), an Hsp70/Hsp90 organizing protein (Hop) homologue, mediates the assembly of the Hsp70/Hsp90 chaperone heterocomplex. The mSTI1 protein can be phosphorylated in vitro by cell cycle kinases proximal to a putative nuclear localization signal (NLS), which substantiated a predicted casein kinase II (CKII)-cdc2 kinase-NLS (CcN) motif at position 180-239 and suggested that mSTI1 might move between the cytoplasm and the nucleus under certain cell cycle conditions. The mechanism responsible for the cellular localization of mSTI1 was probed using NIH3T3 fibroblasts to investigate the localization of endogenous mSTI1 and enhanced green fluorescent protein (EGFP)-tagged mSTI1 mutants. Localization studies on cell lines stably expressing NLS(mSTI1)-EGFP and EGFP demonstrated that the NLS(mSTI1) was able to promote a nuclear localization of EGFP. The mSTI1 protein was exclusively cytoplasmic in most cells under normal conditions but was present in the nucleus of a subpopulation of cells and accumulated in the nucleus following inhibition of nuclear export (leptomycin B treatment). G1/S-phase arrest (using hydroxyurea) and inhibition of cdc2 kinase (using olomoucine) but not inhibition of casein kinase II (using 5,6-dichlorobenzimidazole riboside), increased the proportion of cells with endogenous mSTI1 nuclear staining. mSTI1-EGFP behaved identically to endogenous mSTI1. The functional importance of key residues was tested using modified mSTI1-EGFP proteins. Inactivation and phosphorylation mimicking of potential phosphorylation sites in mSTI1 altered the nuclear translocation. Mimicking of phosphorylation at the mSTI1 CKII phosphorylation site (S189E) promoted nuclear localization of mSTI1-EGFP. Mimicking phosphorylation at the cdc2 kinase phosphorylation site (T198E) promoted cytoplasmic localization of mSTI1-EGFP at the G1/S-phase transition,whereas removal of this site (T198A) promoted the nuclear localization of mSTI1-EGFP under the same conditions. These data provide the first evidence of nuclear import and export of a major Hsp70/Hsp90 co-chaperone and the regulation of this nuclear-cytoplasmic shuttling by cell cycle status and cell cycle kinases.
- Full Text:
Nuclear translocation of the Hsp70/Hsp90 organizing protein mSTI1 is regulated by cell cycle kinases
- Authors: Longshaw, Victoria M , Chapple, J Paul , Cheetham, Michael E , Blatch, Gregory L
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6488 , http://hdl.handle.net/10962/d1006271 , https://dx.doi.org/10.1242/jcs.00905
- Description: The co-chaperone murine stress-inducible protein 1 (mSTI1), an Hsp70/Hsp90 organizing protein (Hop) homologue, mediates the assembly of the Hsp70/Hsp90 chaperone heterocomplex. The mSTI1 protein can be phosphorylated in vitro by cell cycle kinases proximal to a putative nuclear localization signal (NLS), which substantiated a predicted casein kinase II (CKII)-cdc2 kinase-NLS (CcN) motif at position 180-239 and suggested that mSTI1 might move between the cytoplasm and the nucleus under certain cell cycle conditions. The mechanism responsible for the cellular localization of mSTI1 was probed using NIH3T3 fibroblasts to investigate the localization of endogenous mSTI1 and enhanced green fluorescent protein (EGFP)-tagged mSTI1 mutants. Localization studies on cell lines stably expressing NLS(mSTI1)-EGFP and EGFP demonstrated that the NLS(mSTI1) was able to promote a nuclear localization of EGFP. The mSTI1 protein was exclusively cytoplasmic in most cells under normal conditions but was present in the nucleus of a subpopulation of cells and accumulated in the nucleus following inhibition of nuclear export (leptomycin B treatment). G1/S-phase arrest (using hydroxyurea) and inhibition of cdc2 kinase (using olomoucine) but not inhibition of casein kinase II (using 5,6-dichlorobenzimidazole riboside), increased the proportion of cells with endogenous mSTI1 nuclear staining. mSTI1-EGFP behaved identically to endogenous mSTI1. The functional importance of key residues was tested using modified mSTI1-EGFP proteins. Inactivation and phosphorylation mimicking of potential phosphorylation sites in mSTI1 altered the nuclear translocation. Mimicking of phosphorylation at the mSTI1 CKII phosphorylation site (S189E) promoted nuclear localization of mSTI1-EGFP. Mimicking phosphorylation at the cdc2 kinase phosphorylation site (T198E) promoted cytoplasmic localization of mSTI1-EGFP at the G1/S-phase transition,whereas removal of this site (T198A) promoted the nuclear localization of mSTI1-EGFP under the same conditions. These data provide the first evidence of nuclear import and export of a major Hsp70/Hsp90 co-chaperone and the regulation of this nuclear-cytoplasmic shuttling by cell cycle status and cell cycle kinases.
- Full Text:
On becoming an African-Asian English academic at Rhodes University
- Authors: Naidu, Samantha
- Date: 2004
- Language: English
- Type: text , article
- Identifier: vital:21926 , http://hdl.handle.net/10962/14392 , https://0-www.jstor.org.wam.seals.ac.za/stable/24487641
- Description: preprint , I arrived at Rhodes University English Department with not much more than a passion for literature. During the last fourteen years I have been able to observe the discipline in operation. My perspective has broadened and deepened, taking in the trajectory from Stanley Kidd and the colonial Cambridge practices, and from what might be termed the 'humanist enterprise of English studies', 1 to the white liberalism of Guy Butler in the middle of the twentieth century, then to the present post-apartheid era of humanities cutbacks and increasing commodification of knowledge.
- Full Text:
- Authors: Naidu, Samantha
- Date: 2004
- Language: English
- Type: text , article
- Identifier: vital:21926 , http://hdl.handle.net/10962/14392 , https://0-www.jstor.org.wam.seals.ac.za/stable/24487641
- Description: preprint , I arrived at Rhodes University English Department with not much more than a passion for literature. During the last fourteen years I have been able to observe the discipline in operation. My perspective has broadened and deepened, taking in the trajectory from Stanley Kidd and the colonial Cambridge practices, and from what might be termed the 'humanist enterprise of English studies', 1 to the white liberalism of Guy Butler in the middle of the twentieth century, then to the present post-apartheid era of humanities cutbacks and increasing commodification of knowledge.
- Full Text:
One hundred years of botany at Rhodes University
- Authors: Lubke, Roy , Brink, Estelle
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6523 , http://hdl.handle.net/10962/d1005954
- Description: The Botany Department of Rhodes University is located in the historic Schonland Building. An indigenous garden was created in its courtyard, mainly of species of the Eastern Cape province, and its growth in diversity and stature mirrors the changes in the department over the years. Professor Selmar Schonland, the founding father of botany at Rhodes, was also the curator/director of the Albany Museum. Under his leadership, systematics was firmly established as a discipline at Rhodes and research on the flora of the Eastern Cape begun, to be continued to this day. Under professors William Isaac (1949–1951) and Edgar Twyman (1951–1973), plant physiology became an important area of study, and future leaders in physiology at other universities obtained degrees under them. Phycology and aquatic ecology became notable disciplines with Mary Pocock’s world-class work in the 1940s on freshwater and marine algae, which inspired others such as head of department Professor Stanley Seagrief (1958–1986) to develop these studies further. Mycology and microbiology were established as major subdisciplines under Noel Smith (1926–1948) and Twyman through to the 1960s, when the Department of Microbiology was established. Early studies in ecology owe their success to Tony Martin (1947–1956) and the link with the Grahamstown Botanical Research Station, when a sound base for plant ecology in the Eastern Cape was established. Coastal ecology became a major focus in the 1970s, when Roy Lubke and Ted Avis concentrated on dunes and the management of coastal regions. This led to the establishment of the Department of Environmental Science in the 1990s. The expertise of the botany staff in teaching and research in a variety of fields is reflected in the careers of its many students around the world.
- Full Text:
- Authors: Lubke, Roy , Brink, Estelle
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6523 , http://hdl.handle.net/10962/d1005954
- Description: The Botany Department of Rhodes University is located in the historic Schonland Building. An indigenous garden was created in its courtyard, mainly of species of the Eastern Cape province, and its growth in diversity and stature mirrors the changes in the department over the years. Professor Selmar Schonland, the founding father of botany at Rhodes, was also the curator/director of the Albany Museum. Under his leadership, systematics was firmly established as a discipline at Rhodes and research on the flora of the Eastern Cape begun, to be continued to this day. Under professors William Isaac (1949–1951) and Edgar Twyman (1951–1973), plant physiology became an important area of study, and future leaders in physiology at other universities obtained degrees under them. Phycology and aquatic ecology became notable disciplines with Mary Pocock’s world-class work in the 1940s on freshwater and marine algae, which inspired others such as head of department Professor Stanley Seagrief (1958–1986) to develop these studies further. Mycology and microbiology were established as major subdisciplines under Noel Smith (1926–1948) and Twyman through to the 1960s, when the Department of Microbiology was established. Early studies in ecology owe their success to Tony Martin (1947–1956) and the link with the Grahamstown Botanical Research Station, when a sound base for plant ecology in the Eastern Cape was established. Coastal ecology became a major focus in the 1970s, when Roy Lubke and Ted Avis concentrated on dunes and the management of coastal regions. This led to the establishment of the Department of Environmental Science in the 1990s. The expertise of the botany staff in teaching and research in a variety of fields is reflected in the careers of its many students around the world.
- Full Text:
Oomashayela phezulu:
- Mazibuko, Nokuthula, Kaschula, Russell H
- Authors: Mazibuko, Nokuthula , Kaschula, Russell H
- Date: 2004
- Language: Zulu
- Type: text , book
- Identifier: http://hdl.handle.net/10962/175323 , vital:42565 , ISBN 9781869284251
- Description: ‘Sam, khawuphole maan, thob'umoya. KungoLwesihlanu namhlanje, sakuba nalo ithuba elininzi ngomso lokuzithethelela ebazalini bethu! Ha, ha, ha!'wagigitheka uBrunette'Thatha nantsi icider, usele!'UBrunette wayonwabile, wayekuthanda futhi ekonwabela ngoku ukusela, kwaye ezi iicider zazingavakali ngathi butywala! Wayeziva efanelekile kwibhulukhwe yakhe ebomvu, ethe nca kuye emzimbeni kakuhle, nehempe awayeyinxibe ngentla ehambelana nayo, nezihlangu ezichophileyo awayezinxibile. Wagqiba kwangexesha ukuphotha iinwele zakhe ngoboya bomsila wehashe, elungele ipati eyayiza kuba ngobo busuku. Yayintle into yokuba abe woluka iinwele zabantu. Ngokwenza njalo wayezenzela.
- Full Text:
- Authors: Mazibuko, Nokuthula , Kaschula, Russell H
- Date: 2004
- Language: Zulu
- Type: text , book
- Identifier: http://hdl.handle.net/10962/175323 , vital:42565 , ISBN 9781869284251
- Description: ‘Sam, khawuphole maan, thob'umoya. KungoLwesihlanu namhlanje, sakuba nalo ithuba elininzi ngomso lokuzithethelela ebazalini bethu! Ha, ha, ha!'wagigitheka uBrunette'Thatha nantsi icider, usele!'UBrunette wayonwabile, wayekuthanda futhi ekonwabela ngoku ukusela, kwaye ezi iicider zazingavakali ngathi butywala! Wayeziva efanelekile kwibhulukhwe yakhe ebomvu, ethe nca kuye emzimbeni kakuhle, nehempe awayeyinxibe ngentla ehambelana nayo, nezihlangu ezichophileyo awayezinxibile. Wagqiba kwangexesha ukuphotha iinwele zakhe ngoboya bomsila wehashe, elungele ipati eyayiza kuba ngobo busuku. Yayintle into yokuba abe woluka iinwele zabantu. Ngokwenza njalo wayezenzela.
- Full Text:
Oral tradition and the creation of late prehistory in Roviana Lagoon, Solomon Islands
- Sheppard, Peter, Walter, Richard, Aswani, Shankar
- Authors: Sheppard, Peter , Walter, Richard , Aswani, Shankar
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/439958 , vital:73723 , ISBN 0975047639
- Description: The use of oral tradition or oral history in archaeology is often a contentious issue. In this paper we briefly review methodological issues surrounding the use of such data and follow this with a case study using our research into the last 1,000 years of prehistory in Roviana Lagoon (New Georgia Group, Solomon Islands). We argue that it is not possible to generalize cross-culturally about the historicity of oral tradition/history. However, in the Roviana case, careful use of ethnohistory and archaeology together indicates that:(a) Roviana oral history is linear;(b) there is a close relationship between genealogical age and radiocarbon age; and (c) the modern uses of the oral tradition by Roviana provide a theory of their use in the past. We conclude that the model for the formation of the Roviana Chiefdom which emerges from the working back and forth between archaeology and ethnohistory has much more explanatory power than one based on either source of data by itself.
- Full Text:
- Authors: Sheppard, Peter , Walter, Richard , Aswani, Shankar
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/439958 , vital:73723 , ISBN 0975047639
- Description: The use of oral tradition or oral history in archaeology is often a contentious issue. In this paper we briefly review methodological issues surrounding the use of such data and follow this with a case study using our research into the last 1,000 years of prehistory in Roviana Lagoon (New Georgia Group, Solomon Islands). We argue that it is not possible to generalize cross-culturally about the historicity of oral tradition/history. However, in the Roviana case, careful use of ethnohistory and archaeology together indicates that:(a) Roviana oral history is linear;(b) there is a close relationship between genealogical age and radiocarbon age; and (c) the modern uses of the oral tradition by Roviana provide a theory of their use in the past. We conclude that the model for the formation of the Roviana Chiefdom which emerges from the working back and forth between archaeology and ethnohistory has much more explanatory power than one based on either source of data by itself.
- Full Text:
Over-expression, purification and biochemical characterization of DOXP reductoisomerase and the rational design of novel anti-malarial drugs
- Authors: Tanner, Delia Caroline
- Date: 2004
- Subjects: Malaria -- Prevention , Malaria -- Drug therapy , Antimalarials -- Therapeutic use , Proteins -- Purification , Amino acids -- Analysis
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3931 , http://hdl.handle.net/10962/d1003990 , Malaria -- Prevention , Malaria -- Drug therapy , Antimalarials -- Therapeutic use , Proteins -- Purification , Amino acids -- Analysis
- Description: Malaria poses the greatest threat of all parasites to human life. Current vaccines and efficacious drugs are available however their use is limited due to toxicity, emergence of drug resistance, and cost. The discovery of an alternative pathway of isoprenoid biosynthesis, the non-mevalonate pathway, within the malarial parasite has resulted in development of novel anti-malarial drugs. 1-Deoxy-D-xylulose-5-phosphate (DOXP) reductoisomerase, the second enzyme in this pathway, is responsible for the synthesis of 2-C-methyl-D-erythritol 4-phosphate (MEP) in an intramolecular rearrangement step followed by a reduction process involving NADPH as a hydrogen donor and divalent cations as co-factors. Fosmidomycin and FR900098 have been identified as inhibitors of DOXP reductoisomerase. However, they lack clinical efficacy. In this investigation recombinant DOXP reductoisomerase from Escherichia coli (EcDXR) and Plasmodium falciparum (pfDXR) were biochemically characterized as potential targets for inhibition. (His)6-EcDXR was successfully purified using nickel-chelate affinity chromatography with a specific activity of 1.77 μmoles/min/mg and Km value 282 μM. Utilizing multiple sequence alignment, previous structural data predictions and homology modeling approaches, critical active site amino acid residues were identified and their role in the catalytic activity investigated utilizing site-directed mutagenesis techniques. We have shown evidence that suggests that Trp212 and Met214 interact to maintain the active site architecture and hydrophobic interactions necessary for substrate binding, cofactor binding and enzyme activity. Replacement of Trp212 with Tyr, Phe, and Leu reduced specific activity relative to EcDXR. EcDXR(W212F) and EcDXR(W212Y) had an increased Km relative to EcDXR indicative of loss in affinity toward DOXP, whereas EcDXR(W212L) had a lower Km of ~8 μM indicative of increased affinity for DOXP. The W212L substitution possibly removed contacts necessary for full catalytic activity, but could be considered a non-disruptive substitution in that it maintained active site architecture sufficient for DOXP reductoisomerase activity. EcDXR(M214I) had 36-fold reduced enzyme activity relative to EcDXR, while its Km (~8 μM) was found to be lower than that of EcDXR. This suggested that the M214I substitution had maintained (perhaps improved) substrate and active site architecture, but may have perturbed interactions with NADPH. Rational drug design strategies and docking methods have been utilized in the development of furan derivatives as DOXP reductoisomerase inhibitors, and the synthesis of phosphorylated derivatives (5) and (6) has been achieved. Future inhibitor studies using these novel potential DOXP reductoisomerase inhibitors may lead to the development of effective anti-malarial drug candidates.
- Full Text:
- Authors: Tanner, Delia Caroline
- Date: 2004
- Subjects: Malaria -- Prevention , Malaria -- Drug therapy , Antimalarials -- Therapeutic use , Proteins -- Purification , Amino acids -- Analysis
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3931 , http://hdl.handle.net/10962/d1003990 , Malaria -- Prevention , Malaria -- Drug therapy , Antimalarials -- Therapeutic use , Proteins -- Purification , Amino acids -- Analysis
- Description: Malaria poses the greatest threat of all parasites to human life. Current vaccines and efficacious drugs are available however their use is limited due to toxicity, emergence of drug resistance, and cost. The discovery of an alternative pathway of isoprenoid biosynthesis, the non-mevalonate pathway, within the malarial parasite has resulted in development of novel anti-malarial drugs. 1-Deoxy-D-xylulose-5-phosphate (DOXP) reductoisomerase, the second enzyme in this pathway, is responsible for the synthesis of 2-C-methyl-D-erythritol 4-phosphate (MEP) in an intramolecular rearrangement step followed by a reduction process involving NADPH as a hydrogen donor and divalent cations as co-factors. Fosmidomycin and FR900098 have been identified as inhibitors of DOXP reductoisomerase. However, they lack clinical efficacy. In this investigation recombinant DOXP reductoisomerase from Escherichia coli (EcDXR) and Plasmodium falciparum (pfDXR) were biochemically characterized as potential targets for inhibition. (His)6-EcDXR was successfully purified using nickel-chelate affinity chromatography with a specific activity of 1.77 μmoles/min/mg and Km value 282 μM. Utilizing multiple sequence alignment, previous structural data predictions and homology modeling approaches, critical active site amino acid residues were identified and their role in the catalytic activity investigated utilizing site-directed mutagenesis techniques. We have shown evidence that suggests that Trp212 and Met214 interact to maintain the active site architecture and hydrophobic interactions necessary for substrate binding, cofactor binding and enzyme activity. Replacement of Trp212 with Tyr, Phe, and Leu reduced specific activity relative to EcDXR. EcDXR(W212F) and EcDXR(W212Y) had an increased Km relative to EcDXR indicative of loss in affinity toward DOXP, whereas EcDXR(W212L) had a lower Km of ~8 μM indicative of increased affinity for DOXP. The W212L substitution possibly removed contacts necessary for full catalytic activity, but could be considered a non-disruptive substitution in that it maintained active site architecture sufficient for DOXP reductoisomerase activity. EcDXR(M214I) had 36-fold reduced enzyme activity relative to EcDXR, while its Km (~8 μM) was found to be lower than that of EcDXR. This suggested that the M214I substitution had maintained (perhaps improved) substrate and active site architecture, but may have perturbed interactions with NADPH. Rational drug design strategies and docking methods have been utilized in the development of furan derivatives as DOXP reductoisomerase inhibitors, and the synthesis of phosphorylated derivatives (5) and (6) has been achieved. Future inhibitor studies using these novel potential DOXP reductoisomerase inhibitors may lead to the development of effective anti-malarial drug candidates.
- Full Text:
Parasitoids associated with the diamondback moth, Plutella xylostella (L.), in the Eastern Cape, South Africa
- Smith, Tamara J, Villet, Martin H
- Authors: Smith, Tamara J , Villet, Martin H
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , conference
- Identifier: http://hdl.handle.net/10962/442795 , vital:74034 , ISBN , https://www.cabidigitallibrary.org/doi/full/10.5555/20093098381
- Description: Seasonal fluctuations of diamondback moth and its hymenopteran parasitoids were recorded weekly from April 1997 to November 1999 at four cabbage sites in the Grahamstown area of the Eastern Cape, South Africa. Two sites were commercial farms with active spraying programmes; the others were unsprayed. Infestation levels were highest during spring (September to November) and autumn (March to May), where 100% infestation of plants was reached at times. The highest infestation was found during the spring months, where 12 larvae/plant were found at the unsprayed sites and between 6 and 10 larvae at the sprayed sites. At the unsprayed sites abundance of diamondback moth larvae and parasitoids was high during 1997, but much lower during 1998 and 1999, indicating possible control by the parasitoids. Nine species of parasitoid were recorded from diamondback moth during this period and four (Cotesia plutellae (Kurdjumov) (Hymenoptera: Braconidae), Diadegma mollipla (Holmgren) (Hymenoptera: Ichneumonidae), Diadromus collaris Gravenhorst (Hymenoptera: Ichneumonidae) and Oomyzus sokolowskii (Kurdjumov) (Hymenoptera: Eulophidae)) showed potential as biological control agents. The highest rate of parasitism was found from mid-autumn to the beginning of winter (April to June) and from mid-spring to the beginning of summer (October to December). Percent parasitism varied throughout the year, ranging between 10% and 80%. Parasitism of 100% was observed when moth numbers were low. Different species of parasitoids were found to be dominant at different times of the year.
- Full Text:
- Authors: Smith, Tamara J , Villet, Martin H
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , conference
- Identifier: http://hdl.handle.net/10962/442795 , vital:74034 , ISBN , https://www.cabidigitallibrary.org/doi/full/10.5555/20093098381
- Description: Seasonal fluctuations of diamondback moth and its hymenopteran parasitoids were recorded weekly from April 1997 to November 1999 at four cabbage sites in the Grahamstown area of the Eastern Cape, South Africa. Two sites were commercial farms with active spraying programmes; the others were unsprayed. Infestation levels were highest during spring (September to November) and autumn (March to May), where 100% infestation of plants was reached at times. The highest infestation was found during the spring months, where 12 larvae/plant were found at the unsprayed sites and between 6 and 10 larvae at the sprayed sites. At the unsprayed sites abundance of diamondback moth larvae and parasitoids was high during 1997, but much lower during 1998 and 1999, indicating possible control by the parasitoids. Nine species of parasitoid were recorded from diamondback moth during this period and four (Cotesia plutellae (Kurdjumov) (Hymenoptera: Braconidae), Diadegma mollipla (Holmgren) (Hymenoptera: Ichneumonidae), Diadromus collaris Gravenhorst (Hymenoptera: Ichneumonidae) and Oomyzus sokolowskii (Kurdjumov) (Hymenoptera: Eulophidae)) showed potential as biological control agents. The highest rate of parasitism was found from mid-autumn to the beginning of winter (April to June) and from mid-spring to the beginning of summer (October to December). Percent parasitism varied throughout the year, ranging between 10% and 80%. Parasitism of 100% was observed when moth numbers were low. Different species of parasitoids were found to be dominant at different times of the year.
- Full Text:
Particle precipitation effects in the daytime E-region in the South Atlantic Anomaly region
- Authors: Haggard, Raymond
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6794 , http://hdl.handle.net/10962/d1003836
- Description: The behaviour of the normal daytime E-layer over the South Atlantic Anomaly region during 23 days of project ISAAC (29 June to 21 July 1983) has been examined. Enhanced production rates due to precipitated electrons were calculated from the observed data and compared well with the production rates from the mean electron fluxes in the range 0.2–26 keV observed from the satellite Atmosphere Explorer-C during 1973–77, discussed by Gledhill and Hoffman.1 The present study shows that there is evidence of a significant source of extra ionization, in addition to solar ultraviolet and X-radiation, in the South Atlantic Anomaly region.
- Full Text:
- Authors: Haggard, Raymond
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6794 , http://hdl.handle.net/10962/d1003836
- Description: The behaviour of the normal daytime E-layer over the South Atlantic Anomaly region during 23 days of project ISAAC (29 June to 21 July 1983) has been examined. Enhanced production rates due to precipitated electrons were calculated from the observed data and compared well with the production rates from the mean electron fluxes in the range 0.2–26 keV observed from the satellite Atmosphere Explorer-C during 1973–77, discussed by Gledhill and Hoffman.1 The present study shows that there is evidence of a significant source of extra ionization, in addition to solar ultraviolet and X-radiation, in the South Atlantic Anomaly region.
- Full Text:
Petrology and geochemistry of Early Cretaceous bimodal continental flood volcanism of the NW Etendeka, Namibia Part 1: introduction, mafic lavas and re-evaluation of mantle source components
- Ewart, A, Marsh, Julian S, Milner, Simon C, Duncan, Andrew R, Kamber, B S, Armstrong, R A
- Authors: Ewart, A , Marsh, Julian S , Milner, Simon C , Duncan, Andrew R , Kamber, B S , Armstrong, R A
- Date: 2004
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/150583 , vital:38986 , https://doi.org/10.1093/petrology/egg083
- Description: The bimodal NW Etendeka province is located at the continental end of the Tristan plume trace in coastal Namibia. It comprises a high-Ti (Khumib type) and three low-Ti basalt (Tafelberg, Kuidas and Esmeralda types) suites, with, at stratigraphically higher level, interstratified high-Ti latites (three units) and quartz latites (five units), and one low-Ti quartz latite. Khumib basalts are enriched in high field strength elements and light rare earth elements relative to low-Ti types and exhibit trace element affinities with Tristan da Cunha lavas.
- Full Text: false
- Authors: Ewart, A , Marsh, Julian S , Milner, Simon C , Duncan, Andrew R , Kamber, B S , Armstrong, R A
- Date: 2004
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/150583 , vital:38986 , https://doi.org/10.1093/petrology/egg083
- Description: The bimodal NW Etendeka province is located at the continental end of the Tristan plume trace in coastal Namibia. It comprises a high-Ti (Khumib type) and three low-Ti basalt (Tafelberg, Kuidas and Esmeralda types) suites, with, at stratigraphically higher level, interstratified high-Ti latites (three units) and quartz latites (five units), and one low-Ti quartz latite. Khumib basalts are enriched in high field strength elements and light rare earth elements relative to low-Ti types and exhibit trace element affinities with Tristan da Cunha lavas.
- Full Text: false